[Show abstract][Hide abstract] ABSTRACT: Targeting breast cancer and more specifically cancer stem cells (CSCs) subpopulation, responsible for tumor growth, resistance and self-renewal, using combination of therapeutic drugs selectively delivered via biocompatible nanocarriers, provide novel approach for effective therapy. Here, we propose to evaluate the potential therapeutic efficacy of combining Paclitaxel and Salinomycin drugs actively targeted to both breast cancer and CSCs in xenograft murine model after conjugation with biocompatible CD44 antibodies conjugated SWCNTs via hydrazone linker allowing pH-responsive release mechanism near the acidic tumor microenvironment. Both in vitro investigations on MDA-MB-231, sorted CSC negative or CSC positive fractions and in vivo evaluations on tumor-bearing mice using noninvasive bioluminescence and magnetic resonance imaging confirmed the enhanced therapeutic effect of the combined therapy compared to treatment with individual drug-conjugated nanocarriers or free drugs suspensions. Thus, confirmed the great promise of the developed SWCNTs drug delivery system for effective breast cancer treatment by targeting and eradicating both whole tumor cells and CSCs populations.
Full-text · Article · Jan 2016 · Journal of Controlled Release
[Show abstract][Hide abstract] ABSTRACT: Background:
Although corticosteroid is a powerful anti-inflammatory drug that is used widely to control asthma, still severe asthmatics can develop steroid resistance. Airway fibroblasts are quite resistant to steroids during Idiopathic pulmonary fibrosis (IPF) and fibrosis in asthmatic lungs is not always controlled. Th-17 regulatory cytokine which are elevated in lung tissues of asthmatics were shown to enhance the survival of various types of cells. STAT factors are central to this anti-apoptotic function. However, it is not yet clear whether these cytokines contribute to steroid hypo-responsiveness in asthma. Therefore, in this study, we investigated the ability of Th-17 regulatory cytokines, specifically IL-21, IL22 and IL23, to protect structural airway cells against dexamethasone-induced apoptosis.
Primary human fibroblasts, ASM cells, and lung endothelial cells line were treated with IL-21, IL-22, and IL-23 cytokines before incubation with dexamethasone and the level of apoptosis was determined by measuring cellular Annexin-V using Flow cytometry.
Our data indicated that treatment with Th-17 regulatory cytokines was effective in inhibiting induced apoptosis for both fibroblasts and endothelial cells but not ASM cells. STAT3 phosphorylation levels were also upregulated in fibroblasts and endothelial upon treatment with these cytokines. Interestingly, inhibiting STAT3 phosphorylation abrogated IL-21, IL-22, and IL-23 anti-apoptotic effect on fibroblasts and endothelial cells.
This data suggest that Th-17 regulatory cytokines may play a critical role in regulating the survival of fibroblasts during asthma, IPF as well as other chronic lung inflammatory diseases leading to enhanced fibrosis. Accordingly, findings of this paper may pave the way for more extensive research on the role of these regulatory cytokines in fibrosis development in various chronic inflammatory diseases.
Preview · Article · Jan 2016 · Respiratory research
[Show abstract][Hide abstract] ABSTRACT: The prevalence of allergic airway diseases such as asthma and rhinitis has increased dramatically to epidemic proportions worldwide. Besides air pollution from industry derived emissions and motor vehicles, the rising trend can only be explained by gross changes in the environments where we live. The world economy has been transformed over the last 25 years with developing countries being at the core of these changes. Around the planet, in both developed and developing countries, environments are undergoing profound changes. Many of these changes are considered to have negative effects on respiratory health and to enhance the frequency and severity of respiratory diseases such as asthma in the general population. Increased concentrations of greenhouse gases, and especially carbon dioxide (CO2), in the atmosphere have already warmed the planet substantially, causing more severe and prolonged heat waves, variability in temperature, increased air pollution, forest fires, droughts, and floods - all of which can put the respiratory health of the public at risk. These changes in climate and air quality have a measurable impact not only on the morbidity but also the mortality of patients with asthma and other respiratory diseases. The massive increase in emissions of air pollutants due to economic and industrial growth in the last century has made air quality an environmental problem of the first order in a large number of regions of the world. A body of evidence suggests that major changes to our world are occurring and involve the atmosphere and its associated climate. These changes, including global warming induced by human activity, have an impact on the biosphere, biodiversity, and the human environment. Mitigating this huge health impact and reversing the effects of these changes are major challenges. This statement of the World Allergy Organization (WAO) raises the importance of this health hazard and highlights the facts on climate-related health impacts, including: deaths and acute morbidity due to heat waves and extreme meteorological events; increased frequency of acute cardio-respiratory events due to higher concentrations of ground level ozone; changes in the frequency of respiratory diseases due to trans-boundary particle pollution; altered spatial and temporal distribution of allergens (pollens, molds, and mites); and some infectious disease vectors. According to this report, these impacts will not only affect those with current asthma but also increase the incidence and prevalence of allergic respiratory conditions and of asthma. The effects of climate change on respiratory allergy are still not well defined, and more studies addressing this topic are needed. Global warming is expected to affect the start, duration, and intensity of the pollen season on the one hand, and the rate of asthma exacerbations due to air pollution, respiratory infections, and/or cold air inhalation, and other conditions on the other hand.
Full-text · Article · Dec 2015 · World Allergy Organization Journal
[Show abstract][Hide abstract] ABSTRACT: Simultaneous inhibition of IL4 and IL13 via the common receptor chain IL4Rα to block adequately their biologic effects presents a promising therapeutic approach to give the additional relief required for asthma patients. In this study, superparamagnetic iron oxide nanoparticles were conjugated with anti-IL4Rα blocking antibodies via polyethylene glycol (PEG) polymers. The delivery of these blocking antibodies to the inflammatory sites in the lung via the developed nanocarriers was assessed using noninvasive free-breathing pulmonary MRI. Biocompatibility assays confirmed the safety of the developed nanocarriers for pre-clinical investigations. For all the investigated formulations, nanocarriers were found to be very stable at neutral pH. However, the stability noticeably decreased with the PEG length in acidic environment and thus the loaded antibodies were preferentially released. Immunofluorescence and fluorimetry assays confirmed the binding of the nanocarriers to the IL4Rα asthma biomarker. Pulmonary MRI performed using an ultra-short echo time sequence allowed simultaneous noninvasive monitoring of inflammatory responses induced by ovalbumin challenge and tracking of the developed nanocarriers, which were found to colocalize with the inflammatory sites in the lung. Targeting of the developed nanocarriers to areas rich in IL4Rα positive inflammatory cells was confirmed using histological and flow cytometry analyses. The anti-IL4Rα-conjugated nanocarriers developed here have been confirmed to be efficient in targeting key inflammatory cells during chronic lung inflammation following intrapulmonary administration. Targeting efficiency was monitored using noninvasive MRI, allowing detection of the nanocarriers’ colocalizations with the inflammatory sites in the lung of ovalbumin-challenged asthmatic mice. Copyright
Full-text · Article · Dec 2015 · Contrast Media & Molecular Imaging
[Show abstract][Hide abstract] ABSTRACT: Background:
The limitation of current breast cancer treatments was elucidated by the presence of cancer stem cells (CSCs) that play essential role in cancer initiation, progression, resistance, recurrence and metastasis. Materials & methods: Biocompatible multimodality single-walled carbon nanotube (SWCNT) nanoprobes were developed. The biodistribution and preferential homing of CD44 antibody-conjugated SWCNTs toward the tumor site were monitored using MRI, single-photon emission computed tomography and near-infrared fluorescence imaging noninvasive imaging modalities.
Quantification of SWCNTs by sensitively measuring iron content in sorted CSC populations using inductively coupled plasma-mass spectrometry confirmed the enhanced selective targeting of anti-CD44 SWCNT and immunohistochemistry analyses revealed enhanced colocalization with areas rich in CD44 receptors.
Discussion & conclusion:
This preclinical study provided encouraging results for efficient targeting of breast CSCs and perspectives for further clinical studies to confirm the efficacy and safety of the designed nanocarriers.
[Show abstract][Hide abstract] ABSTRACT: Purpose
In this study, we aimed to develop novel therapeutic and diagnostic approaches by improving the targeting of doxorubicin-loaded single-walled carbon nanotubes (SWCNTs) to metastatic regions, and monitor their preferential homing and enhanced therapeutic effect using noninvasive free-breathing magnetic resonance imaging (MRI) and bioluminescence imaging.
High-energy flexible magnets were specifically positioned over the metastatic tumor sites in the lungs. SWCNTs biodistribution, tumor progression, and subsequent treatment efficiency were assessed following administration of the magnetically attracted doxorubicin-loaded anti-CD105 conjugated nanocarriers.
The use of high-energy magnets offered improved theranostic effect of doxorubicin-loaded nanocarriers, by magnetically targeting them towards metastatic tumor sites in the lungs. MRI allowed sensitive monitoring of nanocarriers biodistribution in the abdominal organs, their preferential homing towards the metastatic sites, and their enhanced therapeutic effect.
Combination of noninvasive MRI to localize sensitively the tumor sites, with specific positioning of magnets that can enhance the magnetic targeting of nanocarriers, allowed increasing the treatment efficiency.
No preview · Article · Oct 2015 · Molecular Imaging & Biology
[Show abstract][Hide abstract] ABSTRACT: In this study, we investigated whether tacrolimus extracted and purified from the commercial capsules (Prograf® 5 mg) have retained its original quality and activity beyond the capsules expiration date in order to be reused for research purposes after extraction. High-performance liquid chromatography (HPLC) assay method was developed and validated for the quantification of tacrolimus, using cyclosporine A as an internal standard (IS). Moreover, a combination of analytical methods, including nuclear magnetic resonance (NMR), gas chromatography–mass spectrometry (GC-MS), Fourier transform-infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and differential scanning calorimetry (DSC) were used to assess the quality of extracted/purified tacrolimus. Suppression of murine peripheral-blood mononuclear cells (PBMC) proliferation and the levels of interleukin-2 (IL-2) and interferon gamma (IFN-γ) were also assessed. The data obtained showed no detectable differences in the quality profile between the authentic sample and extracted drug. Also, the results showed that the extracted/purified tacrolimus was able to suppress T cell proliferation, induced by concanavalin A, indicating the retained pharmacological activity. We proved that tacrolimus extracted/purified from expired Prograf® capsuled retains its purity and immunosuppressive activity and can be reused for research and possibly in pharmaceutical manufacturing.
No preview · Article · Oct 2015 · AAPS PharmSciTech
[Show abstract][Hide abstract] ABSTRACT: Acute exacerbations of bronchial asthma remain a major cause of frequent Emergency Department (ED) visits by pediatric patients. However, other factors including psychosocial, behavioural and educational, are also reportedly associated with repetitive ED visits. Therefore, it is necessary to determine whether such visits are justifiable.
The objective of this cross-sectional study was to identify risk factors associated with visits to ED by asthmatic children.
Asthmatic children (n = 297) between 1-17 years old were recruited and information collected at the time of visiting an ED facility at two major hospitals.
Asthmatic patients visited the ED 3.9 3.2 times-per-year, on average. Inadequately controlled asthma was perceived in 60.3% of patients. The majority of patients (56.4%) reported not receiving education about asthma. Patients reflected misconceptions about the ED department, including the belief that more effective treatments are available (40.9%), or that the ED staff is better qualified (27.8%). About half of patients (48.2%) visited the ED because of the convenience of being open 24 hours, or because they are received immediately (38.4%). Uncontrolled asthma was associated with poor education about asthma and/or medication use. Patients educated about asthma, were less likely to stop corticosteroid therapy when their symptoms get better (OR:0.55; 95% CI:0.3-0.9; P = 0.04).
This study reports that most patients had poor knowledge about asthma and were using medications improperly, thus suggesting inefficient application of management action plan. Unnecessary and frequent visits to the ED for asthma care was associated with poor education about asthma and medication use. Potential deficiencies of the health system at directing patients to the proper medical facility were uncovered and underline the necessity to improve education about the disease and medication compliance of patients and their parents/guardians.
Full-text · Article · Apr 2015 · Annals of Thoracic Medicine
[Show abstract][Hide abstract] ABSTRACT: IL-17 is a pro-inflammatory mediator that is believed to play a critical role in regulating tissue inflammation during asthma, COPD, as well as other inflammatory disorders. The level of expression of IL-17 has been shown to be upregulated in lung bronchial tissue of asthmatic patients. Several reports have provided further evidence that this cytokine could play a key role in enhancing the migration of inflammatory as well as structural cells of the bronchial lung tissue during asthma and COPD. B cell infiltration to sites of inflammation during inflammatory disorders such as bowel disease, asthma and COPD has been reported. Accordingly, in this study we hypothesized that IL-17 may exert a chemotactic effect on primary B cells during asthma. We observed that B cells from asthmatic patients expressed significantly higher levels of IL-17RA and IL-17RC, compared to those of healthy subjects. Using an in-vitro migration assay, B cells were shown to migrate towards both IL-17A and IL-17F. Interestingly, blocking IL-17A and IL-17F signaling using either anti-IL-17R antibodies or MAP kinase inhibitors prevented in vitro migration of B cell towards IL-17. These observations indicate a direct chemotactic effect of IL-17 cytokines on primary peripheral blood B cells with higher effect being on asthmatic B cells. These findings revealed a key role for IL-17 in enhancing the migration of B cells to the lung tissue during asthma or COPD.
[Show abstract][Hide abstract] ABSTRACT: Objective:
Rs37972 and rs37973 variants in the glucocorticoid-induced transcript 1 gene have been associated with inhaled glucocorticosteroid responsiveness in asthmatics; however, some discrepancies have been also reported. This study aims to determine whether rs37972 and rs37973 SNPs are associated with asthma risk in Saudi Arabian asthmatics.
Two-hundred seventy-one diagnosed asthmatics (3-65 years old) and 387 healthy control subjects of equivalent age were recruited. DNA from peripheral blood was purified, and genotyping of rs37972 and rs37973 SNPs was performed by PCR amplification of segments of interest, followed by Sanger sequencing.
The global frequencies of the minor (risk) alleles were 28% ("T" allele, rs37972) and 30% ("G" allele, rs37973). Yates-corrected Chi-square (χ(2)) tests revealed significant differences between asthmatic and healthy groups, in allele frequencies for rs37973 SNP only (χ(2) = 3.98, Yates' p value = 0.046). Regarding genotype frequencies, a significant difference between asthmatic and healthy groups was observed for variant rs37972 only (χ(2) = 8.19, Yates' p value = 0.016). To determine a possible association of the minor "T" and "G" alleles with asthma, both the recessive and dominant genetic models were tested. For rs37973, none of the genotypes were significantly associated with asthma. Concerning rs37972, the dominant model (C/T + T/T versus C/C) indicated a significant "protective" association with asthma, in which C/T + T/T individuals had lower odds of being asthmatics than C/C individuals (OR = 0.67; 95% CI = 0.48-0.94; p = 0.019*).
The minor alleles "T" and "G" of rs37972 and rs37973 SNPs, respectively, were not significantly associated with increased asthma risk in asthma patients from Saudi Arabia.
No preview · Article · Aug 2014 · Journal of Asthma
[Show abstract][Hide abstract] ABSTRACT: Background
The signal transducer and activator of transcription 6 (STAT6) transduces signals in response to IL-4 and IL-13 cytokine stimulations, resulting in many cell-specific responses. Some common STAT6 SNPs were associated with asthma predisposition and/or IgE levels, although discrepancies have also been reported.
To determine whether STAT6 rs324011 and rs324015 polymorphisms are associated with atopic asthma in Saudi Arabian patients.
A total of 536 Saudi individuals aged 11–70 years old (230 atopic asthmatics, 306 healthy subjects) were recruited. DNA was purified from peripheral blood and genotyping for rs324011 and rs324015 polymorphisms was performed by PCR amplification, followed by cycle sequencing of the purified PCR fragments using BigDye chain terminator and capillary electrophoresis.
By the contrast of alleles tests, no significant differences between asthma and healthy groups were detected for both variants (rs324011: X2 = 0.25, Pearson’s P-value = 0.617; rs324015: X2 = 0.068, Pearson’s P = 0.814).When testing for genotypes, rs324011 homozygous T/T genotype was significantly associated with asthma, when the Recessive model is considered (T/T vs. C/C + C/T) (adjusted, OR = 2.49, 95% CI = 1.18–5.25, Pearson’s P = 0.014∗, Yates’ P = 0.022∗). In contrast, rs324015 variant was not significantly associated with asthma.
Rs324011 homozygous T/T genotype was significantly associated with asthma risk whereas rs324015 genotypes were not in the Saudi population.
[Show abstract][Hide abstract] ABSTRACT: Targeting and noninvasive imaging of a specific alveolar macrophage subpopulation in the lung has revealed the importance for early and better diagnosis and therapy of chronic obstructive pulmonary disease (COPD). In this study, the in vivo effect of pulmonary administration of iron oxide nanoparticles on the polarization profile of macrophages was assessed, and a noninvasive free-breathing magnetic resonance imaging (MRI) protocol coupled with the use of biocompatible antibody-conjugated superparamagnetic iron oxide (SPIO) nanoparticles was developed to enable specific targeting and imaging of a particular macrophage subpopulation in lipopolysaccharide-induced COPD mice model.
Enzyme-linked immunosorbent assay, Real-time polymerase chain reaction, and flow cytometry analysis were performed to assess the biocompatibility of PEGylated dextran-coated SPIO nanoparticles. Specific biomarkers for M1 and M2 macrophages subsets were selected for conjugation with magnetic nanoparticles. MRI protocol using ultra-short echo time sequence was optimized to enable simultaneous detection of inflammation progress in the lung and detection of macrophages subsets. Flow cytometry and immunohistochemistry analysis were finally performed to confirm MRI readouts and to characterize the polarization profile of targeted macrophages.
The tested SPIO nanoparticles, under the current experimental conditions, were found to be biocompatible for lung administration in preclinical settings. Cluster of differentiation (CD)86- and CD206-conjugated magnetic nanoparticles enabled successful noninvasive detection of M1 and M2 macrophage subpopulations, respectively, and were found to co-localize with inflammatory regions induced by lipopolysaccharide challenge. No variation in the polarization profile of targeted macrophages was observed, even though a continuum switch in their polarization might occur. However, further confirmatory studies are required to conclusively establish this observation.
Coupling of magnetic iron oxide nanoparticles with a specific antibody targeted to a particular macrophage subpopulation could offer a promising strategy for an early and better diagnosis of pulmonary inflammatory diseases using noninvasive MRI.
Full-text · Article · Mar 2014 · International Journal of Nanomedicine
[Show abstract][Hide abstract] ABSTRACT: Noninvasive imaging of macrophages activity has raised increasing interest for diagnosis of chronic obstructive respiratory diseases (COPD), which make them attractive vehicles to deliver contrast agents for diagnostic or drugs for therapeutic purposes. This study was designed to monitor and evaluate the migration of differently polarized M1 and M2 iron labeled macrophage subsets to the lung of a LPS-induced COPD animal model and to assess their polarization state once they have reached the inflammatory sites in the lung after intravenous injection. Ex vivo polarized bone marrow derived M1 or M2 macrophages were first efficiently and safely labeled with amine-modified PEGylated dextran-coated SPIO nanoparticles and without altering their polarization profile. Their biodistribution in abdominal organs and their homing to the site of inflammation in the lung was tracked for the first time using a free-breathing non-invasive MR imaging protocol on a 4.7T magnet after their intravenous administration. This imaging protocol was optimized to allow both detection of iron labeled macrophages and visualization of inflammation in the lung. M1 and M2 macrophages were successfully detected in the lung starting from 2 hours post injection with no variation in their migration profile. Quantification of cytokines release, analysis of surface membrane expression using flow cytometry and immunohistochemistry investigations confirmed the successful recruitment of injected iron labeled macrophages in the lung of COPD mice and revealed that even with a continuum switch in the polarization profile of M1 and M2 macrophages during the time course of inflammation a balanced number of macrophage subsets predominate.
[Show abstract][Hide abstract] ABSTRACT: The IL-4 receptor alpha subunit (IL-4Rα), when associated with the common gamma chain receptor, or the IL-13Rα1 subunit, transduces signals to STAT6 in response to IL-4 and IL-13 stimulations. This results in a number of cell-specific responses including Th2 differentiation, lymphocyte proliferation and IgE production. Given the prominent role of IL-4Rα in allergic disorders, several single-nucleotide polymorphisms (SNPs) have been found associated with asthma and other atopic disorders, including rs1805010 (I75V) and rs1801275 (Q576R) SNPs; however, lack of significant association have also been reported for some ethnic groups. The objective of this study was to determine whether IL-4Rα rs1805010 and rs1801275 polymorphisms are associated with asthma in patients from Saudi Arabia.
One hundred and ninety severe asthmatic patients (11-70 years old) and 194 healthy subjects of equivalent age range were recruited for blood donation. DNA was purified and genotyping for rs1801275 and rs1805010 polymorphisms in the IL-4Rα gene was performed by PCR amplification, followed by cycle sequencing of the purified PCR fragments using BigDye chain terminator and capillary electrophoresis.
Pearson's Chi-square tests showed that the minor alleles, G, for both rs1805010 and rs1801275 SNPs, were significantly more frequent in asthmatics than in the healthy group (Yates' P < 0.05); conversely, the major alleles, A, were significantly more frequent in healthy than in asthmatics (P < 0.05). Concerning association analysis, odds for A/G-G/G genotypes were significantly higher to be associated with asthma predisposition (rs1801275: OR = 2.12; 95% CI = 1.39-3.22; P < 0.001*; rs1805010: OR = 1.6; 95% CI = 1.01-2.53; P < 0.05*; dominant model). Analysis of gender-genotype interactions, with genders nested within A/G-G/G, indicated higher odds for females than males of significant association with asthma (rs1801275: OR = 5.19, 95% CI = 2.09-12.94*; rs1805010: OR = 3.73, 95% CI = 2.06-6.74*). Rs1805010 and rs1801275 were in linkage disequilibrium (D' = 0.27; P < 0.0004*), with G-G haplotype being more frequent in asthmatics than in healthy subjects (OR = 2.43, 95% CI = 1.59-3.71*).
The risk alleles, G, of IL-4Rα rs1805010 and rs1801275 SNPs and corresponding A/G-G/G genotypes were significantly associated with asthma predisposition in asthmatics from Saudi Arabia.
Full-text · Article · Mar 2014 · Annals of Thoracic Medicine