Article

Ellagitannins from Pomegranate Ameliorates 5-Fluorouracil-Induced Intestinal Mucositis in Rats while Enhancing Its Chemotoxicity against HT-29 Colorectal Cancer Cells through Intrinsic Apoptosis Induction

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Abstract

Worldwide, colorectal cancer (CRC) is a deleterious disease causing millions of death annually. 5-Fluorouracil (5-FU) is a first-line chemotherapy for CRC, but chemoresistance and gastrointestinal mucositis limit its efficacy. Polyphenol-rich foods are increasingly popular due to their potential beneficial role in cancer. Ellagitannins is a group of phenolic compounds commonly found in pomegranate, strawberries, raspberries, etc. The objective of this study was to explore whether ellagitannins from pomegranate (PETs) could ameliorate 5-FU-induced intestinal mucositis and enhance its efficacy against CRC. The results showed that PETs (100 mg/kg) counteracted 5-FU-induced intestinal mucositis in rats. The number of apoptotic cells per crypt was reduced from 1.50±0.21 to 0.85±0.18 (P<0.05). Moreover, PETs induced HT-29 CRC cell death through intrinsic apoptosis as demonstrated by dissipation of mitochondrial membrane potential, increased Bax to Bcl-2 ratio, and cleavage of caspase 9 and caspase 3. PETs and 5-FU combination treatments exhibited synergistic cytotoxicity against HT-29 cells with a weighted combination index of 0.3494. PETs (80 µg/mL) and 5-FU (40 µg/mL) treatments for 48 h induced 14.03±0.76% and 16.42±1.15% of HT-29 cells to undergo apoptosis while the combination treatment further increased apoptosis cells to 34.00±1.54% (P<0.05). Combination treatment of the cells also enhanced S phase cell cycle arrest as compared with PETs or 5-FU monotherapy (P<0.05). These results suggest that dietary ellagitannins from pomegranate could alleviate intestinal mucositis in rats induced by 5-FU while enhancing its toxicity against HT-29 cells through potentiation of apoptosis and cell cycle arrest.

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... Polyphenols can become pro-oxidants to generate this additional oxidative stress in cancer cells, primarily through the generation of reactive oxygen species (ROS) (Khan et al., 2014). We have previously reported that polyphenols from Chinese herbal medicine pomegranate peels induce apoptosis in colorectal cancer cells (Chen et al., 2018). ...
... The extracts were combined and diluted to 10 ml with water for further analysis. Preparation procedures for the punicalagin fraction as well as punicalagin and granatin B fraction were previously described (Chen et al., 2018). From 20 g of pomegranate peel powder, 1.32 ± 0.14 g of punicalagin and 0.82 ± 0.25 g of the granatin B and punicalagin rich fraction were obtained, respectively. ...
... LC-MS/MS analysis was performed by an Agilent 1290 infinity LC system with API 3200 Q Trap and controlled by Analyst software (Chen et al., 2018). Mobile phase A was 0.2% acetic acid aqueous solution and B was ACN. ...
Article
Background : Colorectal cancer ranks among the most common cancers. 5-Fluorouracil (5-FU) based first-line chemotherapy for colorectal cancer treatment often leads to chemoresistance and gastrointestinal mucositis. Purpose : This study aimed to find potential therapeutic agents from herbal medicine with anti-colorectal cancer and anti-mucositis activities. Methods : Chinese medicine theory, network pharmacology analyses, and antioxidant activity coupled with liquid chromatography tandem mass spectrometry analyses were used to identify potential bioactive compounds. HT-29 human colorectal cancer cell culture and xenograft tumor models were employed to study anti-colorectal cancer efficacy. Lipopolysaccharide-induced RAW 264.7 and 5-FU treated Dark Agouti rats were used to evaluate anti-inflammatory and anti-mucositis activities. Histological staining, immunofluorescence imaging, western blots, and flow cytometric analyses were employed to explore the underlying mechanisms. Results : Both Chinese medicine theory and network pharmacology analyses indicated pomegranate peels as a potential anti-colorectal cancer and anti-mucositis agent. Antioxidant activity coupled with liquid chromatography tandem mass spectrometry analyses revealed granatin B and punicalagin as the most potent antioxidant compounds in pomegranate peels. Granatin B and punicalagin demonstrated superior anti-colorectal cancer activities in both cell culture and xenograft tumor models. Granatin B and punicalagin also exhibited strong anti-inflammatory activities in lipopolysaccharide-induced RAW264.7 cells and anti-mucositis activities in 5-FU-treated rats. Mechanistic studies revealed that granatin B and punicalagin induced reactive oxygen species-mediated S-phase cell cycle arrest and apoptosis in HT-29 cells. Moreover, these compounds sensitized HT-29 cells to 5-FU-induced cell death and S-phase cell cycle arrest. Conclusion : We report that granatin B and punicalagin exhibit superior anti-colorectal cancer and anti-mucositis activities. To the best of our knowledge, these results are novel and suggest that utilizing phenols from herbal medicine, such as granatin B and punicalagin, to target reactive oxygen species may be an innovative therapy to treat colorectal cancer and intestinal mucositis.
... Thus, considering the possible role of the mediators evaluated here also in intestinal mucositis associated with chemotherapy, the effect of PPJE was also studied in IECs treated with 5-FU. Previous studies already suggested a protective effect of pomegranate juice in intestinal mucositis, at the level of intestinal epithelial cells [58], but the novelty of this study rests, in particular, on the use of a nontumorigenic cell line and in the evaluation of parameters potentially involved in the five-phase model of mucositis development, proposed by Sonis [8]. In brief, the stages of this model include the phases of (1) initiation, (2) upregulation, (3) signal amplification, (4) ulceration and (5) healing. ...
... The reduction of apoptotic rate was also associated with a significant reduction in caspase-3 expression. These results agree with previous data reporting the ability of ellagitannins from pomegranate to ameliorate intestinal mucositis and reduce apoptosis of intestinal cells induced by 5-FU in rats [58]. In most cases, mucositis is an acute phenomenon that is self-resolving once cancer therapy ends. ...
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Intestinal epithelial cells (IECs) play a pivotal role in maintaining intestinal homeostasis. Different noxious agents, among them also anticancer therapies, can impair intestinal epithelial integrity triggering inflammation and oxidative stress. A frequent complication of chemotherapy is gastrointestinal mucositis, strongly influencing the effectiveness of therapy, increasing healthcare costs, and impairing patients’ quality of life. Different strategies are used to treat gastrointestinal mucositis, including products from natural sources. Our study focused on the effect of pomegranate (Punica granatum L.) juice extract on IEC-6 cells, both during inflammatory conditions and following treatment with 5-fluorouracil (5-FU). The polyphenolic profile of pomegranate juice was characterized in detail by Online Comprehensive two dimensional Liquid Chromatography-Mass Spectrometry. The evaluation of pomegranate juice extract in IEC-6 indicates a significant inhibition in proinflammatory factors, such as cytokines release, cyclooxygenase-2 and inducible nitric oxide synthase expression, and nitrotyrosine formation. Pomegranate also inhibited oxidative stress and adhesion protein expression. In 5-FU-treated IEC-6, pomegranate also inhibited both inflammatory and oxidative stress parameters and apoptosis. It promoted wound repair and tight junction expression. These results suggest a potential use of pomegranate as an adjuvant in the treatment of intestinal inflammatory and oxidative stress states, which also occur during chemotherapy-induced mucositis.
... However, treatment with 5-FU not only destroys neoplastic cells, it also affects cell populations of healthy tissue throughout the body (Duncan and Grant, 2003;Chen et al., 2018). More than 50% of patients treated with 5-FU suffer from oral and intestinal mucositis, which are accompanied by pain, bacteremia, and malnutrition (Decker-Baumann et al., 1999;Liu et al., 2012;Tang et al., 2017). ...
... After cooling to room temperature, the supernatant was used. Western blotting and data analysis were performed according to Chen et al. (2018). Antibodies used (all from Solarbio) were anti-NLRP3 polyclonal antibody (rabbit, 1:1,000), anti-Bcl2 polyclonal antibody (rabbit, 1:1,000) and anti-β-actin polyclonal antibody (rabbit, 1:1,000) and goat anti-rabbit IgG/horseradish peroxidase antibody (rabbit, 1:5,000). ...
Article
5-Fluorouracil (5-FU) is widely used as a chemotherapeutic drug for the treatment of cancer but it has toxic side effects. It can induce severe intestinal damage and even lead to death. The purpose of this study was to investigate whether milk fermented with Lactobacillus rhamnosus FLRH93 could alleviate intestinal damage induced by 5-FU. The results of injury intervention in a mouse model showed that milk fermented with Lb. rhamnosus FLRH93 significantly ameliorated intestinal injury caused by 5-FU. The results of hematoxylin and eosin staining showed that mice fed Lb. rhamnosus FLRH93 preserved the villus/crypt ratio and reduced the loss of goblet cells in ileum sections of 5-FU-treated animal. Further, administration of fermented milk upregulated expression of Bcl-2 in the intestinal tract and downregulated the expression of NLRP3, thus reducing the production of inflammatory factors interleukin 1-β and tumor necrosis factor-α. The survival rate of mice treated with fermented milk was twice that of mice not fed fermented milk after continuous oral administration of 5-FU. In conclusion, Lb. rhamnosus FLRH93 has positive effects on body injury and could be used to prevent intestinal damage caused by cancer chemotherapy.
... Breast cancer is the most commonly investigated cancer using different types of cell lines MDA-MB-231 cells, MCF-7, HepG-2 and PC-3 (Badawi et al., 2018;Bagheri et al., 2018;Ahmadiankia et al., 2018). coming to the colorectal cancer, in-vitro studies using HT-29 CRC cell line and in vivo design on dark agouti rats and Apc-mutated Pirc rats' experiments have been done (Chen et al., 2018;Keta et al., 2020). In addition, ovarian carcinoma, hepatocellular carcinoma, bladder carcinoma, cervical carcinoma, osteosarcoma, thyroid carcinoma, and skin cancer (Li et al., 2014;El-Ashmawy et al., 2016;Song et al., 2016;Keta et al., 2020;Sharifi-Rad et al., 2020;Gonzalez-Castillo et al., 2021). ...
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Background Oral squamous cell carcinoma (OSCC) is one of the most common cancers globally. Considering the drawbacks of the traditional treatment phytochemicals have been introduced to the research field with consideration of their minimal, or no side effects and good efficacy against cancer cells. Pomegranate peel and blueberries are very well-known phytochemicals in this context. Material and methods Methanolic extracts are prepared from both pomegranate peel (PPE) and blueberry (BE) dried powders. The antioxidant content was determined by ORAC assay for both extracts. The cytotoxic levels of the extracts and IC50 on the HNO-97 cell line were defined using the colorimetric SRB assay. Then flow cytometric apoptosis analysis of the IC50 of both extracts was performed. Finally, an investigation of the metastasis through the wound healing assay was performed for both extracts. Results A significant difference in the antioxidant content was found between PPE and BE ethanolic extracts. The Ic50 for the PPE-treated cell line was 73.35 µg/ml while the BE showed it at 525.38 µg/ml with a significant difference between them. Both PPE and BE showed significant induction of cancer cell apoptosis with much better results with PPE treatment. The wound healing assay showed significant inhibition of cell migration when treated with PPE while there was not any significant effect on cell migration when treated with BE. Conclusion With the consideration that, the Phytochemicals used are well-known fruits with no harm on normal tissues. Low doses of PPE exert incredibly significant alteration in the HNO-97 tongue cancer cell proliferation, inducing apoptosis and inhibition of cancer cell migration. Meanwhile, treatment with BE needs much higher doses for showing anti-proliferative properties of cancer cells and induce cancer cell apoptosis. This gives promising results for further investigations about using them as a treatment or adjunctive treatment for oral cancer cases.
... Nevertheless, methanol extract of O. ficus-indica peels possessed the cytotoxic mechanism of action by decreasing cell proliferation and apoptosis induction in the cancer cells. This was confirmed by enhancing the gene Bax expression of pre-apoptosis as well as reducing the gene Bcl-2 expression of anti-apoptosis [46,47]. ...
... An in vitro study reported that PPE remarkably inhibited the proliferation of HepG2 cells by promoting apoptosis (Song, Li, and Li 2016). Chen et al. (2018) showed that PPE could inhibit the proliferation of HT-29 cells and lead to cell cycle arrest at S-phase. In addition, PJ could significantly inhibit the proliferation of HeLa and PC3 cells in a dose-dependent manner (Les et al. 2015). ...
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Gut microbiota (GM) is an invisible organ that plays an important role in human health. Increasing evidence suggests that polyphenols in pomegranate (punicalagin, PU) could serve as prebiotics to modulate the composition and function of GM. In turn, GM transform PU into bioactive metabolites such as ellagic acid (EA) and urolithin (Uro). In this review, the interplay between pomegranate and GM is thoroughly described by unveiling a dialog in which both actors seem to affect each other's roles. In a first dialog, the influence of bioactive compounds from pomegranate on GM is described. The second act shows how the GM biotransform pomegranate phenolics into Uro. Finally, the health benefits of Uro and that related molecular mechanism are summarized and discussed. Intake of pomegranate promotes beneficial bacteria in GM (e.g. Lactobacillus spp., Bifidobacterium spp.) while reducing the growth of harmful bacteria (e.g. Bacteroides fragilis group, Clostridia). Akkermansia muciniphila, and Gordonibacter spp., among others, biotransform PU and EA into Uro. Uro contributes to strengthening intestinal barrier and reducing inflammatory processes. Yet, Uro production varies greatly among individuals and depend on GM composition. Uro-producing bacteria and precise metabolic pathways need to be further elucidated therefore contributing to personalized and precision nutrition.
... It exhibits it anticancer efficacy by inhibiting DNA and RNA synthesis (Miura et al., 2010;Shiga and Hiraide, 2020). However, 5-FU is also notable for its severe side effects such as cardiotoxicity and mucositis Chen et al., 2018). Numerous studies have shown that 5-Fu cardiotoxicity is mediated by formation of reactive oxygen species (ROS) leading to oxidative stress and subsequent activation of several inflammatory and apoptotic pathways. ...
Article
5-fluorouracil (5-FU) is an efficacious fluoropyrimidine antimetabolite anticancer drug, however, its clinical utility is constrained due to side effect toxicity on delicate organs, including the heart. This study thus aimed at exploring the cardioprotective potentials of naringin (NRG) against 5-FU-induced cardiotoxicity in rats. We divided Wistar rats into four experimental groups (n=6) for the administration of NRG (100 mg/kg bw, orally) and/or 5-FU (150 mg/kg bw, intraperitoneal). NRG was administered for 10 days, while 5-FU was injected on the 8th day only. Serum troponin-I (cTn-I) and creatine kinase (CK) were estimated. Cardiac activities/level of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), reduced glutathione (GSH), malondialdehyde (MDA), interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS) and nuclear factor-ĸB (NF-κB) and caspase-3 were determined. 5-FU markedly increased cTn-I, CK, cardiac inflammatory mediators and caspase-3 expressions, whereas antioxidant mediators decreased appreciably when compared to the control groups. Interestingly, the prophylactic administration of NRG prominently inhibited the 5-FU-provoked oxidative stress, pro-inflammation and apoptosis in the heart of rats. Histopathology confirmed the biochemical results of the heart. Therefore, NRG is a potential natural flavonoid for mitigation of 5-FU cardiotoxicity in rats
... Moreover, it is able to elicit apoptosis in colorectal cancer cells by cytochrome c release and caspase 9 and caspase 3 stimulation [77]. Chen and colleagues reported the potential colorectal cancer and chemotherapy-induced intestinal mucositis therapy of pomegranates [78]. We confirm these results by reporting pomegranates' positive predictive role on mucositis. ...
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Background: The use of herbs to treat illnesses was common in all historical eras. Our aim was to describe the phytotherapeutic substances that cancer patients use most commonly, and to determine whether their use can increase side effects. Methods: This was a retrospective and descriptive study conducted among older adults actively undergoing chemotherapy, admitted at the Oncology DH Unit (COES) of the Molinette Hospital AOU Città della Salute e della Scienza in Turin (Italy). Data collection was conducted through the distribution of self-compiled and closed-ended questionnaires during chemotherapy treatment. Results: A total of 281 patients were enrolled. Evaluating retching and sage consumption was statistically significant in multivariate analysis. The only risk factor for dysgeusia was chamomile consumption. Ginger, pomegranate, and vinegar use were retained as mucositis predictors. Conclusions: Phytotherapeutic use needs more attention in order to decrease the risks of side effects, toxicity, and ineffective treatment. The conscious administration of these substances should be promoted for safe use and to provide the reported benefits.
... Several studies pointed to the potential neuroprotective effect of many constituents present in PP, that is, ellagitannins (Tejada et al., 2017) ellagic acid to prevent against myelin-associated sphingolipid loss in EAE, and further its metabolite urolithin, which stimulated ceramide biosynthesis in glioma (Busto et al., 2018), and to suggest that more studies should be conducted on PP as a neuropro- thyroid Liu et al., 2017), uterine, breast (Dikmen et al., 2011;Fazio et al., 2018), bladder (Chang et al., 2018), prostate (Deng et al., 2017), leukemia (Panth et al., 2017), and osteosarcoma (Li et al., 2014). Moreover, its ellagitannins enhanced the chemotoxicity of 5-fluorouracil in colorectal cancer cell lines through apoptosis potentiation and to lessen its side effects in rats (Chen, Lam, et al., 2018). The synergism between natural extracts and chemotherapeutic agents has been extensively reported in the literature (Atteya et al., 2017) and extend herein to include pomegranate peel. ...
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Pomegranate is an ancient shrub, globally distributed nowadays. It has been used in the middle east as a medicinal food and traditional medicine for thousands of years. Pomegranate peel (PP) constitutes about 50% of the total fruit, however, it has been previously regarded as a waste. Recent research points to PP as a rich source of phenolics (e.g., ellagitannins, flavonoids, and anthocyanins), polysaccharides, in addition to its biotransformed metabolites viz. urolithins making it a valuable waste with promising pharmacological actions. Compared to the pulp and the juice, PP exhibited stronger antioxidant and antimicrobial activities. Besides, it inhibited inflammation in several conditions, including colitis, arthritis, hepatitis, contact dermatitis, and lung inflammation. Moreover, it displayed anti-osteoporosis, anti-hyperglycemic, antidiabetic, antihypertensive, vasculoprotective, hepatoprotective, neuroprotective, and immunomodulatory effects. Additionally, it was effective as a prebiotic and in obesity control, besides it promoted wound healing. Furthermore, PP demonstrated anticancer effects against different cancer types, for example, colon, liver, thyroid, uterine, breast, bladder, prostate, leukemia, and osteosarcoma. Despite PP safety, it may interfere with the metabolism of other drugs because it inhibits cytochromes (CYP) changing their bioavailability, effectiveness, and toxicity. PP biowaste valorization not only avoids against its environmental and economic burden but can also provide a promising platform to produce novel or improved nutraceuticals. This study provides a comprehensive overview of PP biological activities with the reported action mechanisms related to its phytochemicals and further biotransformed metabolites inside the body. Future research prospects to unravel the merits of such waste and optimize its use are discussed. Practical application Pomegranate is widely distributed throughout the world. Although its peel was previously considered a waste, recent research regards it as a rich source of bioactive compounds with promising biological activities. Its recycling not only overcomes the bio-waste problems, but also provides a source of valuable compounds with several health benefits. In recent years, PP has been demonstrated to exhibit excellent pharmacological bioactivities, for example, antioxidant, anti-inflammatory, antimicrobial, antiosteoporosis, antihyperlipidemic, and anticancer activities. Its health-promoting power is mostly attributed to the phenolic and polysaccharide content, in addition to its amazing biotransformed metabolites. The underlying action mechanisms of such pharmacological activities are discussed and related to its chemical content. This review presents the latest research progress on the role of PP in the prevention and treatment of various chronic diseases, and its protective health effects for future research to be used in nutraceuticals.
... Banerjee et al. [105] demonstrated that polyphenolic extract from pomegranate juice exerted cytotoxic, anti-inflammatory and antiangiogenesis effects on HT-29 cells via upregulation of caspase-3, PARP cleavage, downregulation of COX-2, vascular cell adhesion molecule 1 (VCAM-1), VEGF, and NF-B p65, reduction in phosphorylation of phosphatidylinositol 3kinase/protein kinase B (PI3K/Akt) and increase in the expression of miRNA-126. Recently, Chen et al. [106] showed that both pomegranate peel-derived ellagitannins alone and ellagitannins in combination with 5-fluorouracil (5-FU) significantly inhibited HT-29 cell proliferation and induced S-phase cell cycle arrest. Concomitant mechanistic studies showed induction of intrinsic apoptosis via dissipation of mitochondrial membrane potential, increased Bax to Bcl-2 ratio, and cleavage of caspase-3 and caspase-9. ...
Article
Cancer remains to be the second highest cause of mortality in our society, falling just short of heart disease. Despite major advancement in cancer therapy over the past decade, momentum has been gaining for an alternative approach of using naturally-occurring and dietary agents for cancer prevention and management. Research on pomegranate (Punica granatum L.), a fruit of the Punicaceae family, has shown enormous potential for cancer prevention and intervention. In addition to a rich source of polyphenols, including flavonoids and ellagitannins, in its juice, pomegranate also houses hundreds of other phytochemicals in its pericarp, seed, flower, bark, flowers and leaves, These phytochemicals provide powerful antiproliferative, anti-inflammatory, antioxidant, anti-invasive, antimigratory, anti-angiogenic and anti-metastatic effects without significant toxicity. This makes the use of its various extracts a very attractive strategy to our current battle against cancer. This review article presents a systematic, comprehensive and critical review of research on pomegranate-derived products in both cancer prevention and intervention. It discusses the chemical constituents of pomegranate, the results of both preclinical (in vitro, ex vivo and in vivo) and clinical studies on the anticancer effect of pomegranate phytochemicals and molecular targets in numerous types of cancers, such as breast, gastrointestinal tract (oral, colon, liver and pancreas), gynecological (uterine and ovarian), hematological (lymphoma, leukemia and myeloma), lung, neurological (glioma), urogenital (bladder and prostate), bioavailability, pharmacokinetics and safety of pomegranate constituents. In order to guide the direction of future research, we have also included current limitations and challenges in the field and our post analysis recommendation.
... They used lactate dehydrogenase, 3-(4,5-Dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium bioassays, acridine orange-ethidium bromide, and terminal deoxyribonucleotidyl transferasemediated dUTP nick-end labeling to study the cytotoxic and growth inhibition effects of pomegranate extracts and genistein on MCF-7 cancer cells. Similar studies were also carried out by Dikmen et al. (2011) to demonstrate that the methanolic extract of pomegranate peel at varied concentrations (25,50,100,200, and 300 μg/ml) Ameliorates 5-FU-induced intestinal mucositis Chen et al. (2018) HT-29 CRC cell line Induces intrinsic apoptosis with a decrease in mitochondrial potential, increases bcl-2-like protein 4 (BAX) to Bcl-2 ratio, and cleaves caspase-9 and caspase-3 Apc-mutated Pirc rats Stimulates type I procollagen synthesis and inhibits matrix metalloproteinase-1 (MMP-1; interstitial collagenase) production by dermal fibroblasts that promote the regeneration of dermis (Aslam et al. 2006) (continued) decreased cell proliferation and stimulated apoptosis in MCF-7 cancer cells. This was evident from the enhanced expression of pre-apoptotic gene Bax and decrease in the expression of anti-apoptotic gene Bcl-2. ...
Chapter
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Cancer is one of the prominent death causing diseases around the globe. About 1 in 6 deaths is due to cancer and its related diseases. Cancer mortality can be reduced by early diagnosis and screening, implementing effective treatments. A precise cancer identification is vital for effective treatment, because each cancer type requires a definite treatment procedure, such as radiotherapy, surgery, and chemotherapy. The brisk expansion of herbal therapy and escalating ongoing clinical studies are becoming trendy and useful in the drug development against cancer. Pomegranate (Punica granatum) is a prehistoric fruit with illustrious dietary and remedial properties in alternative traditional systems of medicine. The current chapter is aiming to understand various model systems (in silico, in vitro, and in vivo), employed for studying its anti-cancerous properties and diverse molecular effects exhibited by the pomegranate peel and its phytoconstituents. It also highlights the importance of secondary metabolites of P. granatum, especially ellagitannins and their anticancer properties. Although there are enormous in vitro and preclinical data, human clinical trials are sorely lacking. The major focus is on up-to-date investigations into the outcomes of previously reported pomegranate peel components against a diverse type of cancers.
... Therefore, anticancer drugs may cause some side effects on immune system. 5-Fluorouracil (5-FU) is an effective antitumor drug and it is still in first-line chemotherapy to treat various kinds of cancers, including lung , breast (Boncel et al., 2016), liver (Qi et al., 2016), colorectal (Chen et al., 2018), and pancreatic cancers (Wang et al., 2014). Moreover, 5-FU has important side effects such as myelosuppression, cardiotoxicity and gastrointestinal toxicity (Potikanond et al., 2015;Takimoto et al., 1996). ...
Article
Due to the toxicity and resistance to treatment with anticancer drugs, various methods are used to improve their efficacy in cancer treatment. In this present study, in order to overcome the limitation of 5-Fluorouracil (5-FU), prodrug strategy has been pursued with using density functional theory (DFT) and molecular dynamics simulation (MDs). The main objective of this study is to examine the mechanisms of drug release from its prodrug form by using the intrinsic reaction coordinate (IRC) calculations. The reaction mechanisms of 5-FU prodrug (EMC-5-FU) in the presence of lactic acid (LA) and water molecule were theoretically studied. The IRC calculations were carried out at the M06-2X/6-311G** level in the aqueous phase through the mechanism of ester hydrolysis to obtain energies, the geometry optimization of all stationary points along the potential energy surfaces (PES), and also to determine the harmonic vibrational frequencies. The results herein presented suggest that three reaction pathways and transition states TS1 to TS2 are involved along the calculated potential energy surface. We found that the drug molecule is released in the third step and this occurs by separation CH2O group in the presence of water molecule with the highest energy barrier about 25.9 kcal/mol. Since the carbon nanotubes (CNTs) can act as drug delivery vehicles and deliver anticancer drugs directly to the target cells. Therefore in DFT section, the interaction mechanism of CNTs with 5-FU prodrug is studied by means of DFT method. The atoms in molecules (AIM) and the non-covalent interactions (NCI) between the CNTs and prodrug are used in order to examine the strength and type of interaction between them. The result of negative binding energy values of CNT-prodrug interaction show the stability of these complexes. Our theoretical results show that the more favorable interaction occurs when the prodrug is located inside the carbon nanotube. Furthermore, for design and development of intracellular drug delivery systems, steered molecular dynamics (SMD) simulations was used to investigate the possibility of encapsulated prodrug-CNT penetration through a (1-palmitoyl-2-oleoyl phosphatidylcholine) POPC lipid bilayer. For this purpose, the forces of penetration and the free energies of rupture of POPC bilayer with a Prodrug-CNT were studied. Our simulation results show that encapsulated prodrug-carbon nanotube does not permanently destroy the POPC membrane structure.
... Aynı zamanda yapılan son çalışmalar incelendiğinde nar kabuğunun potansiyel bir anti-karsinojen olabileceğini görülmektedir 15 . Kemoterapötikler ile nar kabuğu ekstresinin kombine tedavisinin tedaviyi desteklediği ve daha güçlü anti kanser etki oluştuğu da önceki çalışmalarda gösterilmiştir 16 . Ancak nar kabuğunun kanser kemoterapisine bağlı gelişebilecek nörotoksisiteye karşı nasıl bir etki göstereceği konusunda bir bilgi bulunmamaktadır. ...
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Introduction: This study pointed to validate the phytochemistry, antioxidant and antimutagenic activities of two common plant peels; Punica granatum L. and Opuntia ficus-indica L. Material and methods: HPLC analysis was performed for identification of phenolics and flavonoids, beside to isolation of some triterpenes and phenolics from both plant peels. Results: P. granatum peels composed of 16 flavonoids and 18 phenolics, while O. ficus-indica comprised of 18 flavonoids and 10 phenolics. α-Amyrin acetate (1), friedelin (2), lup-20(29)-en-3β-ol (3), quercetin-3,4'-dimethyl ether-7-O-α-Larabinofuranosyl β-D-glucopyranoside (4), punicaflavanol (5), and two hydrolyzabl tannins (6&7) were isolated from P. granatum peels, while friedelin (8), 24-Methylene-ergosta-5-en-3β-ol (9), apigenin-7-O-glucoside (10), isorhamnetin 3-O-β-D-glucopyranoside (11), and betanin pigment (12) were isolated from O. ficus-indica peels. Compounds (1-5 and 8, 10, 11, 12) were isolated for the first time from both plant peels. P. granatum and O. ficus-indica peel extracts have relatively significant antioxidant, cytotoxic and antimutagenic effects. Discussion and conclusion: The tested plant peel extracts could be a reliable source as natural antioxidant, antimutagenic and cytotoxic agents with a high level of safety. The novelty of this study is the comparison of such activities of the peels under study.
Article
Objective: To evaluate the protective function of Babao Dan (, BBD) on 5-flurouracil (5-FU)-induced intestinal mucositis (IM) and uncover the underlying mechanism. Methods: A total of 18 male mice were randomly divided into 3 groups by a random number table, including control, 5-FU and 5-FU combined BBD groups, 6 mice in each group. A single intraperitoneal injection of 5-FU (150 mg/kg) was performed in 5-FU and 5-FU combined BBD groups on day 0. Mice in 5-FU combined BBD group were gavaged with BBD (250 mg/kg) daily from day 1 to 6. Mice in the control group were gavaged with saline solution for 6 days. The body weight and diarrhea index of mice were recorded daily. On the 7th day, the blood from the heart of mice was collected to analyze the proportional changes of immunological cells, and the mice were subsequently euthanized by mild anesthesia with 2% pentobarbital sodium. Colorectal lengths and villus heights were measured. Intestinal-cellular apoptosis and proliferation were evaluated by Tunel assay and immunohistochemical staining of proliferating cell nuclear antigen, respectively. Immunohistochemistry and Western blot were performed to investigate the expressions of components in Wnt/β-catenin pathway (Wnt3, LRP5, β-catenin, c-Myc, LRG5 and CD44). Results: BBD obviously alleviated 5-FU-induced body weight loss and diarrhea, and reversed the decrease in the number of white blood cells, including monocyte, granulocyte and lymphocyte, and platelet (P<0.01). The shortening of colon caused by 5-FU was also reversed by BBD (P<0.01). Moreover, BBD inhibited apoptosis and promoted proliferation in jejunum tissues so as to reduce the intestinal mucosal damage and improve the integrity of villus and crypts. Mechanically, the expression levels of Wnt/β -catenin mediators such as Wnt3, LRP5, β-catenin were upregulated by BBD, activating the transcription of c-Myc, LRG5 and CD44 (P<0.01). Conclusions: BBD attenuates the adverse effects induced by 5-FU via Wnt/β-catenin pathway, suggesting it may act as a potential agent against chemotherapy-induced intestinal mucositis.
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Cancer is still a major public health burden because its incidence and mortality continue to increase worldwide. The limited treatment options for patients with advanced stages, the severe toxicity, the onset of multiple drug resistance and the high costs of current anticancer therapies favor poor prognosis and high mortality rates. Thus, the identification and development of preventive and cost effective therapeutic strategies to reverse cancer-associated morbidity and mortality are needed. Vegetable and fruit consumption is associated with decreased risk of cancer because of its chemopreventive and chemotherapeutic effects. The use of Punica granatum preparations has a long ethnomedical history and preclinical research has reported many pharmacological activities, including chemopreventive, chemosensitisation and chemotherapeutic effects. Many of these health beneficial effects are related to its complex chemical composition and synergistic interactions of its colonic microbial metabolites including ellagic acid, ellagitannins, punicic acid, flavonoids, anthocyanidins, anthocyanins, and estrogenic flavonols. This chapter summarizes the scientific evidence supporting anticancer effects of pomegranate constituents, focusing on its molecular targets and anticancer mechanisms of action, along with a critical evaluation of pomegranate polyphenols as future anticancer agents.
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Nature is a rich source of natural drug-like compounds with almost zero side effects. Phytochemicals better known as “Natural Products” are found abundantly in a number of plants. Since time immemorial, spices have been widely used in Indian cuisine as flavoring and colouring agents. Most of these spices and condiments are derived from various biodiversity hotspots in India (which contributes 75% of global spice production) and form the crux of India’s multidiverse and multicultural cuisine. Apart from their aroma, flavor and taste, these spices and condiments are known to possess several medicinal properties also. Most of these spices find considerable mention in Ayurveda, the indigenous system of medicine, as panaceas for several aliments. The antimicrobial, antioxidant, antiproliferative, antihypertensive and antidiabetic properties of several of these natural products are well documented in Ayurveda. These phytoconstituemts are known to act as functional immunoboosters, immunomodulators as well as anti-inflammatory agents. As anticancer agents, their mechanistic action involves cancer cell death via induction of apoptosis, necrosis and autophagy. The present review provides a comprehensive and collective update on the potential of 65 commonly used spices as well as their bioactive constituents as anticancer agents. The review also provides an in-depth update of all major in vitro, in vivo, clinical and pharmacological studies done on these spices with special emphasis on the potential of these spices and their bioactive constituents as potential functional foods for prevention, treatment and management of cancer.
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Consumption of dietary ellagitannins (ETs) has been proven to benefit multiple chronic health disorders including cancers and cardiovascular diseases. Urolithins, gut microbiota metabolites derived from ETs, are considered as the molecules responsible for these health effects. Previous studies have demonstrated that urolithins exhibit antiproliferative effects on prostate, breast, and colon cancers. However, as for hepatocellular carcinoma (HCC), it remains elusive. Herein, we aim to investigate the function of urolithin B (UB), a member of urolithins family, in HCC. The effects of UB on cell viability, cell cycle and apoptosis were evaluated in HCC cells, and we found UB could inhibit the proliferation of HCC cells, which resulted from cell cycle arrest and apoptosis. Furthermore, UB could increase phosphorylated β‐catenin expression and block its translocation from nuclear to cytoplasm, thus inducing the inactivation of Wnt/β‐catenin signaling. Using a xenograft mice model, UB was found to suppress tumor growth in vivo. In conclusion, our data demonstrated that UB could inhibit the proliferation of HCC cells in vitro and in vivo via inactivating Wnt/β‐catenin signaling, suggesting UB could be a promising candidate in the development of anticancer drugs targeting HCC. We firstly reported that UB, the gut metabolites of ETs, suppress tumorigenesis of HCC in vitro and in vivo via inactivating Wnt/β‐catenin signaling.
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Chemotherapeutic medications, including 5 – fluorouracil (5FU), are the same old technique to most cancers and are associated with numerous peripheral toxicities. We investigated exopolysaccharide (EPSST) produced from the isolated streptomycete of the Mediterranean Sea for the capability to lower the severity of mucositis in vivo. The streptomycete was isolated from Mediterranean Sea sediment from the beaches of Port Said Governorates, Egypt and identified morphologically, physiologically, and biochemically and confirmed by molecularly 16S rDNA analysis. The EPSST was extracted from the supernatant of streptomycete by using 4 volumes chilled ethanol and then the functional groups, MW, and chemical evaluation have been detected via Fourier-transform infrared (FTIR), and high-performance liquid chromatography (HPLC). In addition, antioxidant activity was measured through the usage of 2, 2-diphenyl-1-picrylhydrazyl (DPPH). Thirty-two male rats (180–200 g) were randomly divided into a control group (normal saline), intraperitoneal injection of 5-fluorouracil (5-FU, 150 mg/kg), normal rats were treated with EPSST and 5-FU + EPSST group. These groups were continued up to the day of sacrifice (28 days post treatments). The isolated strain became recognized based totally on 16S rDNA sequence as Streptomyce sp. with accession number SAMN08349905. The chemical evaluations of EPSST were galacturonic, glucose, galactose, mannose, and arabinose with a relative ratio of 2.1: 1: 5.37: 1.62: 1.29 individually, with an average molecular weight (Mw) 9.687 × 10³ g/mol. Also, the EPSST contained uronic acid (16%) and sulfate (12.149%) and no protein was detected. EPSST inhibited the DPPH radical activity. The findings of this study propose that EPSST inhibits 5-FU-induced mucositis through adjustment of oxidative stress, apoptosis, inflammatory factors, activation of antioxidant enzymes. The clinical administration of EPSST may recover the chemotherapy-induced intestinal dysfunction, consequently increasing the clinical efficiency of chemotherapy. In addition, the administration of EPSST reduced 5-FU-induced histopathological incongruities such as neutrophil infiltration, loss of cellular integrity, and villus and crypt distortion. The clinical administration of EPSST may recover the chemotherapy-induced intestinal dysfunction, consequently increasing the clinical efficiency of chemotherapy.
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Colorectal cancer is a leading cause of cancer-related mortality worldwide, with Fluorouracil (5-FU)-based chemotherapy as the major treatment for advanced disease. Many patients with advanced colorectal cancer eventually succumb to the disease despite some patients responded initially to chemotherapy. Thus, identifying molecular mechanisms responsible for chemotherapy resistance will help design novel strategies to treat colorectal cancer. In this study, we established an acquired 5-FU resistant cell line, LoVo-R, from LoVo cells. Through exome sequencing, we discovered that elevated GLI1 signaling axis is a major genetic alteration in the 5-FU resistant cells. Hh signaling, a pathway essential for embryonic development, is an important regulator for residual cancer cells. We demonstrated that knockdown of GLI1 or GLI2 sensitized LoVo-R cells to 5-FU treatment, reduced cell invasiveness. The relevance of our studies to colorectal cancer patients is reflected by our discovery that high expression of GLI1 signaling molecules was associated with a high incidence of cancer relapse and a shorter survival in a larger cohort of colorectal cancer patients who underwent chemotherapy (containing 5-FU). Taken together, our data demonstrate the critical role of the GLI1 signaling axis for 5-FU resistance in colorectal cancer. Electronic supplementary material The online version of this article (doi:10.1186/s13578-017-0145-7) contains supplementary material, which is available to authorized users.
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Background: 3-4methylenedioxymethamphetamine (MDMA) is a synthetic and psychoactive drug, which is known popularly as Ecstasy and has toxic effects on human organs. Objectives: Considering the potential toxic interaction, this study was performed to quantify the expression of bax and bcl2 genes in MDMA-induced hepatotoxicity on rat liver. Subsequently, we evaluated pentoxifylline as a possible protective drug on hepatotoxicity. Materials and methods: Adult male Wistar rats weighting 250 - 300 grams were used in the study. The rats were equally distributed into four experimental groups (5 rat/group). MDMA was dissolved in PBS and injected intraperitoneally (IP) including untreated control, MDMA (MDMA dissolved in PBS), treated-1 (MDMA followed by PTX) and treated-2 (PTX followed by MDMA). All animals given MDMA received 3 doses of 7.5mg/kg with two hours gap between doses. Liver tissue was removed after anaesthetizing. Subsequently, RNA isolation, cDNA synthesis and Real-Time PCR were performed. Finally, data analyzed statistically to determine significantly differences between the groups (P value < 0.05). Results: Using Real-Time quantitative PCR results, the gene expression ratio of bcl2 were calculated 93.80±20.64, 340.45 ± 36.60 and 47.13 ± 5.84 fold in MDMA, treated-1 and treated-2 groups, respectively. Furthermore, this ratio for bax gene obtained 2.13±0.33 fold in MDMA, 1.55 ± 0.26 fold in treated-1 and 10.44 ± 1.56 fold in treated-2 groups. Conclusions: The present study focused on molecular mechanism of MDMA in programmed cell death using gene expression quantification of a pro-apoptotic and anti-apoptoic gene in MDMA-induced hepatotoxocity. The results showed that MDMA prompted apoptosis in liver and pentoxifylline protected against hepatotoxicity before and after taking MDMA.
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Beneficial effects of L-arginine on immune responses and bowel function have been reported. Mucositis is a side effect of chemotherapy treatment that affects approximately 40% of patients. This complication is characterized by inflammation that affects the gastrointestinal tract, increasing permeability and causing abdominal pain, nausea, vomiting, and diarrhea, which worsen the patient's nutritional status and increases morbimortality. The aim of this study was to evaluate the effect of pretreating with 2% L-arginine supplementation in water on mucositis as induced by 5-fluorouracil (5-FU; a single dose of 200 mg/kg body weight) in Swiss male mice. The effect of L-arginine on weight, intestinal permeability, morphology, and the histopathological score of the small intestine (from 0 to 12), oxidative stress, myeloperoxidase (MPO), and N-acetylglucosaminidase (NAG) activities were evaluated. Intestinal length improvement was observed, in addition to the partial recovery of the mucosal architecture. L-arginine attenuated the histopathological score and MPO activity. There was also an improvement in intestinal permeability, despite weight loss after 5-FU administration. In conclusion, L-arginine can positively impact intestinal mucositis by promoting partial mucosal recovery, reducing inflammation and improving intestinal permeability. Full-text version: http://www.tandfonline.com/eprint/cEMvxw4BPVPhJB6VfcYy/full
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Proanthocyanidins (PAs) from Caryota ochlandra fruit pericarp and fruit flesh were characterized by 13C nuclear magnetic resonance, high performance liquid chromatography–electrospray ionization mass spectrometry, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry techniques. The fruit pericarp and flesh PAs were complex mixtures of homo- and heteropolymers of B-type procyanidins and prodelphinidins both with degrees of polymerization up to dodecamer. Their antioxidant and antityrosinase activities were investigated. The fruit pericarp PAs exhibited potent antioxidant activity with IC50 values of 142.86 ± 1.53 and 80.51 ± 0.4 μg/ml for DPPH and ABTS free-radical scavenging assays; with FRAP value of 373.09 ± 5.02 mg ascorbic acid equivalent/g dry weight. Furthermore, the fruit pericarp PAs had antityrosinase activity while the fruit flesh PAs could be oxidized by tyrosinase. The structure and antioxidant activities of the C. ochlandra fruit PAs together with their effects on tyrosinase activity would lay scientific foundation for their utilization in food and nutrition industry.
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The mechanisms of apoptosis induction and mitotic inhibition in the intestinal epithelium were investigated in male BDF1 mice treated with a single oral dose of 5-fluorouracil (5-FU). We measured the concentrations of 5-FU in the plasma and intestinal tissues and followed the detailed incidental time courses of both apoptotic index (AI) and mitotic index (MI) in the five intestinal compartments. Although the plasma concentration of 5-FU decreased to a value lower than the minimal effective concentration (MEC) within 8 hr after administration, the intestinal tissue concentrations remained remarkably higher than the MEC until 48 hr. 5-FU induced an increases of AI and decrease of MI for more than 48 hr with time courses that differed among the intestinal compartments. We also determined the AI and MI after administration of two 5-FU derivatives, 5'-DFUR and Capecitabine. The derivatives were administered orally at the equivalent dose of 5-FU; nevertheless the observed changes of AI and MI were far less significant than those for 5-FU. This finding may reflect the number of enzymatic activation steps each compound undergoes and explain why the toxicities of the 5-FU derivatives in the intestinal epithelium are less than that of 5-FU itself. The present study suggests that the prolonged effect of 5-FU would be due to retention of 5-FU within the intestinal epithelium, and that the different time courses for AI and MI in each intestinal compartment would depend on the stage that the cell-cycle was in when 5-FU uptake occurred.
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5-Fluorouracil (5-FU) is an anti-metabolite that is in clinical use for treatment of several cancers. In cells, it is converted into three distinct fluoro-based nucleotide analogs, which interfere with DNA synthesis and repair, leading to genome impairment and, eventually, apoptotic cell death. Current knowledge states that in certain cell types, 5-FU-induced stress is signaling through a p53-dependent induction of tumor necrosis factor-receptor oligomerization required for death-inducing signaling complex formation and caspase-8 activation. Here we establish a role of calcium (Ca(2+)) as a messenger for p53 activation in response to 5-FU. Using a combination of pharmacological and genetic approaches, we show that treatment of colon carcinoma cells stimulates entry of extracellular Ca(2+) through long lasting-type plasma membrane channels, which further directs posttranslational phosphorylation of at least three p53 serine residues (S15, S33 and S37) by means of calmodulin (CaM) activity. Obstructing this pathway by the Ca(2+)-chelator BAPTA (1,2-bis(o-aminophenoxy)ethane- N,N,N',N'-tetraacetic acid) or by inhibitors of CaM efficiently reduces 5-FU-induced caspase activities and subsequent cell death. Moreover, ectopic expression of p53 S15A in HCT116 p53(-/-) cells confirmed the importance of a Ca(2+)-CaM-p53 axis in 5-FU-induced extrinsic apoptosis. The fact that a widely used therapeutic drug, such as 5-FU, is operating via this pathway could provide new therapeutic intervention points, or specify new combinatorial treatment regimes.Oncogene advance online publication, 29 October 2012; doi:10.1038/onc.2012.467.
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Journal of Cerebral Blood Flow & Metabolism stands at the interface between basic and clinical neurovascular research, and features research on experimental, theoretical, and clinical aspects of brain circulation, metabolism and imaging. The journal is relevant to any physician or scientist with an interest in brain function, cerebrovascular disease, cerebral vascular regulation and brain metabolism, including neurologists, neurochemists, physiologists, pharmacologists, anesthesiologists, neuroradiologists, neurosurgeons, neuropathologists and neuroscientists.
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An antioxidant fraction of Chinese green tea (green tea antioxidant; GTA), containing several catechins, has been previously shown to inhibit 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced tumor promotion in mouse skin. In the present study, GTA was shown to have antioxidative activity toward hydrogen peroxide (H2O2) and the superoxide radical (O2−). GTA also prevented oxygen radical and H2O2-induced cytotoxicity and inhibition of intercellular communication in cultured B6C3F1 mouse hepatocytes and human keratinocytes (NHEK cells). GTA (0.05–50 μg/ml) prevented the killing of hepatocytes (measured by lactate dehydrogenase release) by paraquat (1–10 mM) and glucose oxidase (0.8–40 μg/ml) in a concentration-dependent fashion. GTA (50μg/ml) also prevented the inhibition of hepatocyte intercellular communication by paraquat (5 mM), glucose oxidase (0.8 μg/ml), and phenobarbital (500 μg/ml). In addition, GTA (50 μg/ml) prevented the inhibition of intercellular communication in human keratinocytes by TPA (100 ng/ml). Cytotoxicity and inhibition of intercellular communication, two possible mechanisms by which tumor promoters may produce their promoting effects were therefore prevented by GTA. The inhibition of these two effects of pro-oxidant compounds may suggest a mechanism by which GTA inhibits tumor promotion in vivo.
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Fas is expressed in colonic epithelial cells and is also expressed in colon carcinomas, although its functional significance in the regulation of apoptosis in cells outside of the immune system remains unknown. In this study, we determined the role of Fas signaling on cellular growth of cultured colon carcinoma cells and demonstrated apoptosis induced by a cytotoxic anti-Fas monoclonal antibody (CH-11) in cells of the GC3/c1 lineage (GC3/c1, TS-, Thy4) but not in HCT116 or CaCo2 cells. Growth inhibition was detected at concentrations of CH-11 as low as 1 ng/ml, and clonogenic survival studies yielded IC50 values of 3-26 ng/ml. Cytotoxicity was inhibited by ZB4, a monoclonal antibody inhibitory to Fas signaling. In addition, the survival factor Bcl-2, which has demonstrated inconsistent protective effects against Fas signaling in other systems, was inhibitory to Fas-induced apoptosis in colon carcinoma cells after adenoviral transduction. Fas was expressed at the highest levels in TS- and Thy4 cells, which were the most sensitive cell lines to Fas-induced apoptosis. FAP-1, a protein tyrosine phosphatase that interacts with the cytosolic negative regulatory domain of Fas, was expressed in each cell line but did not correlate with sensitivity to Fas-mediated apoptosis. These data have therefore identified a functional Fas pathway in colon carcinoma cells when Fas is expressed at high levels. Hence, the role of Fas signaling in the regulation of apoptosis in colon carcinoma cells and its role in influencing the response to treatment with chemotherapeutic agents should be further explored.
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Apoptosis and related forms of cell death have central importance in development, homeostasis, tumor surveillance, and the function of the immune system. Apoptosis is initiated by two principal pathways. The intrinsic pathway emerges from mitochondria, whereas the extrinsic pathway is activated by the ligation of death receptors. This Viewpoint introduces the basic mechanisms of the extrinsic pathway, using the example of the prototypical death receptor Fas and its role in apoptosis, but it also points out the increasingly understood importance of this receptor as a non-apoptotic signal transducer.
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To assess the association of dietary flavonol intake with the subsequent risk of coronary heart disease (CHD) mortality. Meta-analysis of prospective cohort studies published before September 2001. Studies were identified by MEDLINE and EMBASE searches and by scanning relevant reference lists. The following information was extracted from published reports: size of cohort, mean age, mean duration of follow-up, number of fatal CHD events, mean flavonol intake, main sources of flavonol intake, degree of adjustment for potential confounders, and the relation of CHD mortality to dietary flavonol intake measured at baseline. Seven prospective cohorts of men and women were identified including a total of 2087 fatal CHD events. Comparison of individuals in the top third with those in the bottom third of dietary flavonol intake yielded a combined risk ratio of 0.80 (95% CI 0.69-0.93) after adjustment for known CHD risk factors and other dietary components. This overview of prospective cohort studies indicates that high dietary intake of flavonols from a small number of fruits and vegetables, tea and red wine may be associated with a reduced risk from CHD mortality in free-living populations.
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Chemotherapy and radiotherapy, whilst highly effective in the treatment of neoplasia, can also cause damage to healthy tissue. In particular, the alimentary tract may be badly affected. Severe inflammation, lesioning and ulceration can occur. Patients may experience intense pain, nausea and gastro-enteritis. They are also highly susceptible to infection. The disorder (mucositis) is a dose-limiting toxicity of therapy and affects around 500 000 patients world-wide annually. Oral and intestinal mucositis is multi-factorial in nature. The disruption or loss of rapidly dividing epithelial progenitor cells is a trigger for the onset of the disorder. However, the actual dysfunction that manifests and its severity and duration are greatly influenced by changes in other cell populations, immune responses and the effects of oral/gut flora. This complexity has hampered the development of effective palliative or preventative measures. Recent studies have concentrated on the use of bioactive/growth factors, hormones or interleukins to modify epithelial metabolism and reduce the susceptibility of the tract to mucositis. Some of these treatments appear to have considerable potential and are at present under clinical evaluation. This overview deals with the cellular changes and host responses that may lead to the development of mucositis of the oral cavity and gastrointestinal tract, and the potential of existing and novel palliative measures to limit or prevent the disorder. Presently available treatments do not prevent mucositis, but can limit its severity if used in combination. Poor oral health and existing epithelial damage predispose patients to mucositis. The elimination of dental problems or the minimization of existing damage to the alimentary tract, prior to the commencement of therapy, lowers their susceptibility. Measures that reduce the flora of the tract, before therapy, can also be helpful. Increased production of free radicals and the induction of inflammation are early events in the onset of mucositis. Prophylactic administration of scavengers or anti-inflammatories can partially counteract or limit some of these therapy-mediated effects, as can the use of cryotherapy. The regular use of mouthwashes, mouth coatings, antibiotics and analgesics is essential, prior to and during loss and ablation of the epithelial layer. Granulocyte–macrophage colony-stimulating factor/granulocyte colony-stimulating factor or the use of laser light therapy may aid restitution and repair. Glutamine supplements may be beneficial in the repair/recovery phase.
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Small intestinal crypt cells rapidly undergo apoptosis in response to cytotoxic drug treatment that results in gastrointestinal toxicity. The Bcl-2 family have been implicated in both positive and negative regulation of intestinal cell apoptosis. The aim of this study was to examine the effect of cytotoxic treatment on Bcl-2 protein expression in patients and rats with tumours. Four pro- and four anti-apoptotic members of the Bcl-2 family, caspase-3 and p53 were examined in small intestinal crypts before and after treatment in rats and humans. Immunohistochemistry identified changes in protein expression over time, while relative RT-PCR was used to investigate mRNA expression in rat small intestine. Cytotoxic treatment increased p53 and caspase-3 which coincided with elevated levels of apoptosis. Bax and Bak protein and mRNA expression also significantly increased at 6 hours following treatment in rats. Bax and Bak protein increased at day 1 after treatment in humans. Anti-apoptotic Mcl-1 protein decreased within 24hours. Other Bcl-2 family members showed only modest changes. Increased expression of Bax and Bak but not other Bcl-2 family members is associated with apoptosis in small intestinal crypts and may amplify the sensitivity and susceptibility of crypt cells to chemotherapy-induced enteropathy.
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The median-effect equation derived from the mass-action law principle at equilibrium-steady state via mathematical induction and deduction for different reaction sequences and mechanisms and different types of inhibition has been shown to be the unified theory for the Michaelis-Menten equation, Hill equation, Henderson-Hasselbalch equation, and Scatchard equation. It is shown that dose and effect are interchangeable via defined parameters. This general equation for the single drug effect has been extended to the multiple drug effect equation for n drugs. These equations provide the theoretical basis for the combination index (CI)-isobologram equation that allows quantitative determination of drug interactions, where CI < 1, = 1, and > 1 indicate synergism, additive effect, and antagonism, respectively. Based on these algorithms, computer software has been developed to allow automated simulation of synergism and antagonism at all dose or effect levels. It displays the dose-effect curve, median-effect plot, combination index plot, isobologram, dose-reduction index plot, and polygonogram for in vitro or in vivo studies. This theoretical development, experimental design, and computerized data analysis have facilitated dose-effect analysis for single drug evaluation or carcinogen and radiation risk assessment, as well as for drug or other entity combinations in a vast field of disciplines of biomedical sciences. In this review, selected examples of applications are given, and step-by-step examples of experimental designs and real data analysis are also illustrated. The merging of the mass-action law principle with mathematical induction-deduction has been proven to be a unique and effective scientific method for general theory development. The median-effect principle and its mass-action law based computer software are gaining increased applications in biomedical sciences, from how to effectively evaluate a single compound or entity to how to beneficially use multiple drugs or modalities in combination therapies.
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Proanthocyanidins (PAs) have been shown to have potential health benefits. However, no data exist concerning their dietary intake. Therefore, PAs in common and infant foods from the U.S. were analyzed. On the bases of our data and those from the USDA's Continuing Survey of Food Intakes by Individuals (CSFII) of 1994-1996, the mean daily intake of PAs in the U.S. population (>2 y old) was estimated to be 57.7 mg/person. Monomers, dimers, trimers, and those above trimers contribute 7.1, 11.2, 7.8, and 73.9% of total PAs, respectively. The major sources of PAs in the American diet are apples (32.0%), followed by chocolate (17.9%) and grapes (17.8%). The 2- to 5-y-old age group (68.2 mg/person) and men >60 y old (70.8 mg/person) consume more PAs daily than other groups because they consume more fruit. The daily intake of PAs for 4- to 6-mo-old and 6- to 10-mo-old infants was estimated to be 1.3 mg and 26.9 mg, respectively, based on the recommendations of the American Academy of Pediatrics. This study supports the concept that PAs account for a major fraction of the total flavonoids ingested in Western diets.
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In this study, the content, structure, anti-tyrosinase activity and mechanism of longan bark condensed tannins were evaluated. The findings obtained from mass spectrometry demonstrated that longan bark condensed tannins were mixtures of procyanidins, propelargonidins, prodelphinidins, and their acyl derivatives (galloyl and p-hydroxybenzoate). The enzyme analysis indicated that these mixtures were efficient, reversible, and mixed (competitive is dominant) inhibitor of tyrosinase. What’s more, the mixtures showed good inhibitions on proliferation, intracellular enzyme activity and melanogenesis of mouse melanoma cells (B16 ). From molecular docking, the results showed the interactions between inhibitors and tyrosinase were driven by hydrogen bond, electrostatic and hydrophobic interactions. In addition, high levels of total phenolic and extractable condensed tannins suggested that longan bark might be a good source of tyrosinase inhibitor. This study would offer theoretical basis for the development of longan bark condensed tannins as novel food preservative and medicine of skin diseases.
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5-Fluorouracil (5-FU) is a commonly used chemotherapeutic agent for breast cancer. However, its use often leads to drug resistance and mucositis. This study aimed to investigate whether proanthocyanidins from Ficus virens possessed anti-breast cancer and anti-mucositis activities. The results showed that the cytotoxic effects of the proanthocyanidins against MDA-MB-231 and MCF-7 breast cancer cells were in the order of stem barks proanthocyanidins (SPAs) > leaves proanthocyanidins > fruits proanthocyanidins. Moreover, SPAs induced apoptosis in both cell lines which were accompanied with an increase in loss of mitochondrial membrane potential, production of reactive oxygen species, Bax to Bcl-2 protein expression ratio, and activated caspase 3. Furthermore, intraperitoneal injection of 5-FU (150 mg/kg body weight) resulted in body weight loss and jejunal injury in the rats while administration of SPAs (100 mg/kg body weight) counteracted these changes. Collectively, our study demonstrated that SPAs induced apoptosis cell death in breast cancer cells while ameliorating the symptoms of intestinal mucositis in rats.Therefore, SPAs merits further exploration as a potential therapeutic agent for breast cancer and chemotherapy-induced mucositis.
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Breast cancer is the most frequently diagnosed cancer and cause of cancer death in women worldwide. Current treatments often result in systematic toxicity and drug resistance. Combinational use of non-toxic phytochemicals with chemotherapy agents to enhance the efficacy and reduce toxicity would be one promising approach. In this study, bioactive proanthocyanidins from Uncaria rhynchophylla (UPAs) were isolated and their anti-breast cancer effects alone and in combination with 5- fluorouracil (5-FU) were investigated in MDA-MB-231 breast cancer cells. The results showed that UPAs significantly inhibited cell viability and migration ability in a dose-dependent manner. Moreover, UPAs induced apoptosis in a dose-dependent manner which was associated with increased cellular reactive oxygen species production, loss of mitochondrial membrane potential, increases of Bax/Bcl-2 ratio and levels of cleaved caspase 3. Treatments of the cells with UPAs resulted in an increase in G2/M cell cycle arrest. Cytotoxic effects of 5-FU against MDA-MB-231 cells were enhanced by UPAs. The combination treatment of UPAs and 5-FU for 48 h elicited a synergistic cytotoxic effect on MDA-MB-231 cells. Altogether, these data suggest that UPAs are potential therapeutic agents for breast cancer.
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Figure 1. The NF-κB Paradigm of Timely and Flexible Biochemical Control of Cell Behavior
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Objectives: The optimal time to initiate adjuvant chemotherapy after surgery in patients with colon cancer is not clear. We investigated the benefit of combined intraportal chemotherapy administered during radical surgery with adjuvant chemotherapy for treating stage II and III colon cancer. Methods: Patients were randomly assigned to OCTREE arm (intraportal chemotherapy plus mFOLFOX6) or a standard adjuvant chemotherapy arm (mFOLFOX6). The primary study endpoint was disease-free survival. The secondary endpoints included metastasis-free survival, overall survival, and safety. Results: The intent-to-treat population comprised 237 patients. With a median follow-up of 44 months, the hazard ratio (OCTREE vs mFOLFOX6) was 0.66 (95% confidence interval, 0.43-0.90), a 34% risk reduction in favor of OCTREE (P = 0.016). The 3-year disease-free survival rate was 85.2% for OCTREE and 75.6% for mFOLFOX6 alone (P = 0.030). The 3-year metastasis-free survival rates were 87.6% for OCTREE and 78.0% for mFOLFOX6 (P = 0.035). Patients had lower distant metastatic rate in the OCTREE arm (12.7% vs 22.7%; P = 0.044), when compared with the mFOLFOX6 arm. The 3-year overall survival was no significant difference between 2 arms (P = 0.178). Neutropenia occurred in 12.7% of the patients receiving OCTREE and in 2.5% of the patients receiving mFOLFOX6 (P = 0.003) within 2 weeks of surgery, and grade 3 or 4 toxicity event was no difference between 2 regimens. Conclusions: Combination of intraoperative intraportal chemotherapy with mFOLFOX6 reduced the occurrence of distant metastases and improved disease-free survival in patients with stage II and stage III colon cancer.
Article
Background and purpose: Chemotherapeutic agents, including 5-fluorouracil (5-FU), frequently cause intestinal mucositis resulting in severe diarrhoea and morphological mucosal damage. 5-HT₃ receptor antagonists are clinically effective in the treatment of nausea and emesis during cancer chemotherapy. Therefore we here have examined the effects of 5-HT₃ receptor antagonists on 5-FU-induced intestinal mucositis in mice. Experimental approach: Intestinal mucositis was induced in male C57BL/6 mice by daily administration of 5-FU (50 mg·kg⁻¹) for 5 days. Effects of 5-HT₃ receptor antagonists, ramosetron (0.01-0.1 mg·kg⁻¹) and ondansetron (5 mg·kg⁻¹), on the accompanying histology, cytokine production and apoptosis were assessed. Key results: Continuous administration of 5-FU to mice caused severe intestinal mucositis, which was histologically characterized by the shortening of villi and destruction of intestinal crypts, accompanied by body weight loss and diarrhoea. Daily ramosetron administration dose-dependently reduced the severity of intestinal mucositis, body weight loss and diarrhoea. Similar beneficial effects were observed with ondansetron. The number of apoptotic, caspase-3- and caspase-8-activated cells increased 24 h after the first 5-FU administration, and these responses were reduced by ramosetron. The up-regulation of TNF-α, IL-1β and IL-6 following 5-FU treatment was also attenuated by ramosetron. Conclusions and implications: 5-HT₃ receptor antagonists ameliorated 5-FU-induced intestinal mucositis in mice, and this action could result from suppression of apoptotic responses in the intestinal crypt cells via inhibition of cytokine expression. Thus, 5-HT₃ receptor antagonists may be useful for preventing not only nausea and emesis but also intestinal mucositis during 5-FU chemotherapy.
Article
Pomegranate (Punica granatum L.) fruits are widely consumed fresh and in processed forms as juice, jams and wine. Pomegranate fruit husk/peel is a rich source of hydrolyzable tannins called ellagitannins (ETs). In the commercial pomegranate juice (PJ) industry, these ETs are extracted from the husk in significant quantities into the juice due to their hydrophilic properties. Pomegranate husk, a by-product of the PJ industry, is therefore an inexpensive and abundant source of ETs. Previous methods to isolate pomegranate ETs included labor intensive and time-consuming solid phase extractions by column chromatography (C-18, polyamides, cellulose, Sephadex Lipophilic LH-20, Diaion HP20) and/or use of specialized instruments such as preparative-high performance liquid chromatography (HPLC). We have used an Amberlite XAD-16 resin vacuum-aspirated column to rapidly purify an aqueous extract of pomegranate husk to afford total pomegranate tannins (TPT) in substantial yields (58–60 g TPT/kg husk; time <1 h). Using analytical HPLC and tandem LC-ES/MS, evaluation of TPT showed that it contains the major fruit husk ET, punicalagin (80–85% w/w) and ellagic acid (EA; 1.3% w/w) and unquantified amounts of punicalin and EA-glycosides (hexoside, rhamnoside and pentoside). Since pomegranate ETs are reported to show potent antioxidant, antiatherosclerotic and anticancer activities, this method can be used for the large-scale production of TPT for future in vitro and in vivo biological studies. This method is practical for industrial applications and could provide a low-cost means to use a currently underutilized food by-product to develop phytoceuticals with potential health benefits or to develop products for use in the cosmetic and food biopreservative industries.
Article
The aim of the present review is to discuss the cumulative evidence that suggests that pomegranate consumption possesses a diverse array of biological actions and may be helpful in the prevention of some inflammatory-mediated diseases including cancer. The pomegranate fruit can be divided into at least three parts-seeds, peel, and juice. All these components have been studied for their antioxidant properties in a chemoprevention approach. Pomegranate exerts antiproliferative, anti-invasive, and antimetastatic effects, induces apoptosis through modulation of Bcl-2 proteins, increases p21 and p27, and downregulates cyclin-cdk network. In addition, pomegranate inhibits the activation of inflammatory pathways including, but not limited to, the NFκ-B pathway. Anti-cancer effects with the most impressive data have been demonstrated so far in prostate cancer.
Article
Fas is expressed constitutively in colonic epithelial cells and is also expressed in colon carcinomas and in cultured colon carcinoma cell lines. However, the potential role of Fas signaling in mediating apoptosis in cells of this type remains unknown. We have developed human colon carcinoma cell models deficient in thymidylate synthase that demonstrate acute (TS- cells) or delayed (Thy4 cells) apoptosis following DNA damage induced by thymineless stress. Complete protection of cells from acute apoptosis and prolongation of delayed apoptosis was obtained following exposure to the NOK-1 monoclonal antibody (inhibitory to Fas signaling) during the period of dThd deprivation. These results suggested that apoptosis induced by thymineless stress was regulated by autocrine signaling via Fas-FasL interactions. Fas expression was high in both TS- and Thy4 cells. However, FasL, undetectable in synchronous cultures, was up-regulated in TS- cells at 48 hr, when cells were undergoing acute apoptosis, and in Thy4 cells at 96 hr, correlating with the delayed onset of thymineless death. FasL expression also correlated with acute apoptosis induced in parental GC3/cl cells, commencing at 48 hr, following thymidylate synthase inhibition by 5-fluorouracil/leucovorin exposure. Fas-mediated apoptosis induced by the cytotoxic anti-Fas monoclonal antibody CH-11 was inhibited following adenoviral delivery of a Bcl-2 cDNA, and Bcl-2 also protected cells from acute apoptosis induced by dThd deprivation. Taken together, these data demonstrate a functional Fas system in these cultured colon carcinoma cell models, and they demonstrate that Fas-FasL interactions can link DNA damage induced by thymineless stress to the apoptotic machinery of colon carcinoma cells.
Article
To elucidate the relationship between 5-fluorouracil (5-FU) distribution and 5-FU-induced apoptosis and/or cell cycle arrest, microautoradiography was applied to murine intestinal crypts exposed to [14C] 5-FU by intravenous infusion. The histologic location of apoptotic cells in the crypt did not correlate to that of 5-FU. The temporal profiles of apoptotic and/or mitotic indexes corresponded to those of orally administered 5-FU in a previous study. Two cell cycle-related proteins, p21(WAF/Cip1) and bax, were also investigated in the present study. With time, p21(WAF/Cip1)-positive nuclei apparently migrated up the crypt. Bax-positive cytoplasm was observed throughout the crypt epithelial cells, accompanied by the occurrence of apoptosis, and remained until 48 h when the control level recovered. The findings demonstrate that 5-FU mainly exerts an apoptotic effect and/or cell cycle arrest by systemic exposure, and p21 and bax expression determine an individual cell's fate.
Article
Necrotizing enterocolitis (NEC) is a devastating intestinal disease of premature infants. Although end-stage NEC is characterized histopathologically as extensive necrosis, apoptosis may account for the initial loss of epithelium before full development of disease. We have previously shown that epidermal growth factor (EGF) reduces the incidence of NEC in a rat model. Although EGF has been shown to protect intestinal enterocytes from apoptosis, the mechanism of EGF-mediated protection against NEC is not known. The aim of this study was to investigate if EGF treatment elicits changes in expression of apoptotic markers in the ileum during the development of NEC. With the use of a well-established neonatal rat model of NEC, rats were divided into the following three experimental groups: dam fed (DF), milk formula fed (NEC), or fed with formula supplemented with 500 ng/ml EGF (NEC+EGF). Changes in ileal morphology, gene and protein expression, and histological localization of apoptotic regulators were evaluated. Anti-apoptotic Bcl-2 mRNA levels were markedly reduced and pro-apoptotic Bax mRNA levels were markedly elevated in the NEC group compared with DF controls. Supplementation of EGF into formula significantly increased anti-apoptotic Bcl-2 mRNA, whereas pro-apoptotic Bax was significantly decreased. The Bax-to-Bcl-2 ratio for mRNA and protein was markedly decreased in NEC+EGF animals compared with the NEC group. The presence of caspase-3-positive epithelial cells was markedly reduced in EGF-treated rats. These data suggest that alteration of the balance between pro-and anti-apoptotic proteins in the site of injury is a possible mechanism by which EGF maintains intestinal integrity and protects intestinal epithelium against NEC injury.
Article
Polyphenol-rich dietary foodstuffs have attracted attention due to their cancer chemopreventive and chemotherapeutic properties. Ellagitannins (ETs) belong to the so-called hydrolysable tannins found in strawberries, raspberries, walnuts, pomegranate, oak-aged red wine, etc. Both ETs and their hydrolysis product, ellagic acid (EA), have been reported to induce apoptosis in tumour cells. Ellagitannins are not absorbed in vivo but reach the colon and release EA that is metabolised by the human microflora. Our aim was to investigate the effect of a dietary ET [pomegranate punicalagin (PUNI)] and EA on human colon cancer Caco-2 and colon normal CCD-112CoN cells. Both PUNI and EA provoked the same effects on Caco-2 cells: down-regulation of cyclins A and B1 and upregulation of cyclin E, cell-cycle arrest in S phase, induction of apoptosis via intrinsic pathway (FAS-independent, caspase 8-independent) through bcl-XL down-regulation with mitochondrial release of cytochrome c into the cytosol, activation of initiator caspase 9 and effector caspase 3. Neither EA nor PUNI induced apoptosis in normal colon CCD-112CoN cells (no chromatin condensation and no activation of caspases 3 and 9 were detected). In the case of Caco-2 cells, no specific effect can be attributed to PUNI since it was hydrolysed in the medium to yield EA, which entered into the cells and was metabolised to produce dimethyl-EA derivatives. Our study suggests that the anticarcinogenic effect of dietary ETs could be mainly due to their hydrolysis product, EA, which induced apoptosis via mitochondrial pathway in colon cancer Caco-2 cells but not in normal colon cells.
Article
Phytochemicals from fruits such as the pomegranate (Punica granatum L) may inhibit cancer cell proliferation and apoptosis through the modulation of cellular transcription factors and signaling proteins. In previous studies, pomegranate juice (PJ) and its ellagitannins inhibited proliferation and induced apoptosis in HT-29 colon cancer cells. The present study examined the effects of PJ on inflammatory cell signaling proteins in the HT-29 human colon cancer cell line. At a concentration of 50 mg/L PJ significantly suppressed TNFalpha-induced COX-2 protein expression by 79% (SE = 0.042), total pomegranate tannin extract (TPT) 55% (SE = 0.049), and punicalagin 48% (SE = 0.022). Additionally, PJ reduced phosphorylation of the p65 subunit and binding to the NFkappaB response element 6.4-fold. TPT suppressed NFkappaB binding 10-fold, punicalagin 3.6-fold, whereas ellagic acid (EA) (another pomegranate polyphenol) was ineffective. PJ also abolished TNFalpha-induced AKT activation, needed for NFkappaB activity. Therefore, the polyphenolic phytochemicals in the pomegranate can play an important role in the modulation of inflammatory cell signaling in colon cancer cells.
Article
Mucositis is a clinically important and sometimes dose-limiting complication of cancer therapy. Mucositis lesions can be painful, affect nutrition and quality of life, lead to sepsis, and have significant economic impact. Recent modeling of the toxicity has been based on the continuum of clinical signs and symptoms of mucositis involving the alimentary tract, including both oral and gastrointestinal sites. The pathogenesis of oral and gastrointestinal mucositis is multifactorial and complex. In recent years, there has been a substantial increase in both basic and clinical research related to mucosal injury in cancer patients. Since most of this research has been directed to oral mucositis, the present review principally addresses this component of the toxicity. Morbidity, economic impact, pathogenesis and clinical course of mucositis are discussed. In addition, several agents in clinical development for mucositis are discussed in the context of the current pathobiologic model as well as the recently updated evidence-based clinical management guidelines.