Yan-Fang Xian

The Chinese University of Hong Kong, Hong Kong, Hong Kong

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Publications (32)78.56 Total impact

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    ABSTRACT: Pogostemon cablin (Blanco) Benth is a well-known medicinal herb commonly used in many Asian countries for inflammatory diseases. Pogostone (PO), a natural product isolated from P. cablin, is known to exert various pharmacological activities. This study aimed to investigate the anti-inflammatory property of PO, to elucidate its mechanism of action, and to evaluate its potential acute toxicity.
    Journal of ethnopharmacology. 09/2014;
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    ABSTRACT: Ultraviolet (UV) irradiation, known to generate reactive oxygen species (ROS) excessively and elicit inflammatory response, is a potent inducer for skin photoaging. Overproduction of ROS in conjunction with the resulting inflammation stimulate the over-expression of matrix metalloproteinases (MMPs), which in turn causes degradation of extracellular matrix, leading finally to coarse wrinkling, dryness, and laxity of the skin. In this study, patchouli alcohol (PA, C15H26O), an active chemical ingredient reputed for free radical scavenging and anti-inflammatory properties, was investigated for its anti-photoaging action using a mouse model whose dorsal skin was depilated. The dorsal skin areas of six-week-old mice were smeared with PA solution or vehicle, followed by UV irradiation for nine consecutive weeks. Protective effects of PA were evaluated macroscopically and histologically, as well as by assaying the antioxidant enzymes (SOD, GSH-Px) activities, the contents of inflammatory factors (IL-10, IL-6, TNF-α), and the levels of MMP-1 and MMP-3. Our findings amply demonstrated that PA significantly accelerated the recovery of the UV-induced skin lesions, evidently through anti-oxidant and anti-inflammatory action, as well as down-regulation of the MMP-1 and MMP-3 expression.
    European journal of pharmaceutical sciences: official journal of the European Federation for Pharmaceutical Sciences 07/2014; · 2.61 Impact Factor
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    ABSTRACT: Isorhynchophylline (IRN), an alkaloid isolated from Uncaria rhynchophylla, has been reported to improve cognitive impairment induced by beta-amyloid in rats. However, whether IRN could also ameliorate the D-galactose (D-gal)-induced mouse memory deficits is still not clear. In the present study, we aimed to investigate whether IRN had potential protective effect against the D-gal-induced cognitive deficits in mice. Mice were given a subcutaneous injection of D-gal (100 mg/kg) and orally administered IRN (20 or 40 mg/kg) daily for 8 weeks, followed by assessing spatial learning and memory function by the Morris water maze test. The results showed that IRN significantly improved spatial learning and memory function in the D-gal-treated mice. In the mechanistic studies, IRN significantly increased the level of glutathione (GSH) and the activities of superoxide dismutase (SOD) and catalase (CAT), while decreased the level of malondialdehyde (MDA) in the brain tissues of the D-gal-treated mice. Moreover, IRN (20 or 40 mg/kg) significantly inhibited the production of prostaglandin E 2 (PGE2) and nitric oxide (NO), and the mRNA expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), as well as the activation of nuclear factor kappa B (NF-κB) in the brain tissues of D-gal-treated mice. Our results amply demonstrated that IRN was able to ameliorate cognitive deficits induced by D-gal in mice, and the observed cognition-improving action may be mediated, at least in part, through enhancing the antioxidant status and anti-inflammatory effect of brain tissues via NFκB signaling.
    Neurochemistry International 06/2014; · 2.66 Impact Factor
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    ABSTRACT: A mouse model of depression has been recently developed by exogenous corticosterone administration. The present study aimed to examine the antidepressant-like effect and the possible mechanisms of piperine, a major alkaloid of black pepper (Piper nigrum Linn.) and long pepper (P. longum Linn.), in corticosterone-induced depression in mice. The results showed that 3-week corticosterone injections caused depression-like behavior in mice, as indicated by the significant decrease in sucrose consumption and increase in immobility time in the forced swim test and tail suspension test. Moreover, it was found that brain-derived neurotrophic factor protein and mRNA levels in the hippocampus were significantly decreased in corticosterone-treated mice. Treating the animals with piperine significantly suppressed behavioral and biochemical changes induced by corticosterone. The results suggest that piperine produces an antidepressant-like effect in corticosterone-treated mice, which is possibly mediated by increasing brain-derived neurotrophic factor expression in the hippocampus.
    Neurochemistry International 05/2014; · 2.66 Impact Factor
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    ABSTRACT: Previous studies in our laboratory have demonstrated that piperine produced antidepressant-like action in various mouse models of behavioral despair, which was related to the serotonergic system. The present study aimed to examine the behavioral and biochemical effects of piperine in rats exposed to chronic unpredictable mild stress (CUMS). The results showed that CUMS caused depression-like behavior in rats, as indicated by the significant decrease in sucrose consumption and increase in immobility time in the forced swim test. In addition, it was found that serotonin (5-HT) and brain-derived neurotrophic factor (BDNF) contents in the hippocampus and frontal cortex were significantly decreased in CUMS-treated rats. Treating the animals with piperine significantly suppressed behavioral and biochemical changes induced by CUMS. The results suggest that piperine produces an antidepressant-like effect in CUMS-treated rats, which is possibly mediated by increasing 5-HT and BDNF contents in selective brain tissues.
    Cellular and Molecular Neurobiology 01/2014; · 2.29 Impact Factor
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    ABSTRACT: A mouse model of depression has been recently developed by exogenous corticosterone administration. The present study aimed to examine the antidepressant-like effect and the possible mechanisms of piperine, a major alkaloid of black pepper (Piper nigrum Linn.) and long pepper (Piperlongum Linn.), in corticosterone-induced depression in mice. The results showed that 3-weeks corticosterone injections caused depression-like behavior in mice, as indicated by the significant decrease in sucrose consumption and increase in immobility time in the forced swim test and tail suspension test. Moreover, it was found that brain-derived neurotrophic factor protein and mRNA levels in the hippocampus were significantly decreased in corticosterone-treated mice. Treating the animals with piperine significantly suppressed behavioral and biochemical changes induced by corticosterone. The results suggest that piperine produces an antidepressant-like effect in corticosterone-treated mice, which is possibly mediated by increasing brain-derived neurotrophic factor expression in the hippocampus.
    Neurochemistry International 01/2014; · 2.66 Impact Factor
  • Neurochemistry International 01/2014; · 2.66 Impact Factor
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    ABSTRACT: Previous studies in our laboratory have demonstrated that piperine produced antidepressant-like action in various mouse models of behavioral despair. This study aimed to investigate the role of brain-derived neurotrophic factor (BDNF) signalling in the antidepressant-like effect of piperine in mice exposed to chronic unpredictable mild stress (CUMS). The results showed that CUMS caused depression-like behavior in mice, as indicated by the significant decrease in sucrose consumption and increase in immobility time in the forced swim test. It was also found that BDNF protein expression in the hippocampus and frontal cortex were significantly decreased in CUMS-treated mice. Chronic treatment of piperine at the dose of 10mg/kg significantly ameliorated behavioural deficits of CUMS-treated mice in the sucrose preference test and forced swim test. Piperine treatment also significantly decreased immobility time in the forced swim test in naive mice. In parallel, chronic piperine treatment significantly increased BDNF protein expression in the hippocampus and frontal cortex of both naive and CUMS-treated mice. In addition, inhibition of BDNF signalling by injection of K252a, an inhibitor of the BDNF receptor TrkB, significantly blocked the antidepressant-like effect of piperine in the sucrose preference test and forced swim test of CUMS-treated mice. Taken together, this study suggests that BDNF signalling is an essential mediator for the antidepressant-like effect of piperine.
    Behavioural brain research 12/2013; · 3.22 Impact Factor
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    ABSTRACT: The progressive accumulation of amyloid-β (Aβ) in the form of senile plaques has been recognized as a key causative factor leading to the cognitive deficits seen in Alzheimer's disease (AD). Recent evidence indicates that Aβ induces neurotoxicity in the primary neuronal cultures as well as in the brain. Previously, we have demonstrated that isorhynchophylline (IRN), the major chemical ingredient of Uncaria rhynchophylla, possessed potent neuroprotective effects. In the present study, we aimed to investigate the effect of IRN on cognitive function, neuronal apoptosis, and tau protein hyperphosphorylation in the hippocampus of the Aβ25-35-treated rats and to elucidate its action mechanisms. We showed that Aβ25-35 injection caused spatial memory impairment, neuronal apoptosis, and tau protein hyperphosphorylation. Treatment with IRN (20 or 40 mg/kg) for 21 days could significantly ameliorate the cognitive deficits induced by Aβ25-35 in the rats. In addition, IRN attenuated the Aβ25-35-induced neuronal apoptosis in hippocampus by down-regulating the protein and mRNA levels of the ratio of Bcl-2/Bax, cleaved caspase-3 and caspase-9, as well as suppressing the tau protein hyperphosphorylation at the Ser396, Ser404, and Thr205 sites. Mechanistic study showed that IRN could inhibit the glycogen synthase kinase 3β (GSK-3β) activity, and activate the phosphorylation of phosphatidylinositol 3-kinase (PI3K) substrate Akt. These results indicate that down-regulation of GSK-3β activity and activation of PI3K/Akt signaling pathway are intimately involved in the neuroprotection of IRN. The experimental findings provide further evidence to affirm the potential of IRN as a worthy candidate for further development into a therapeutic agent for AD and other tau pathology-related neurodegenerative diseases.
    Journal of Alzheimer's disease: JAD 10/2013; · 4.17 Impact Factor
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    ABSTRACT: The accumulation of extracellular amyloid-β peptide (Aβ) has been considered as one of the important causes of Alzheimer's disease (AD), the most prevalent form of dementia. Hydroxysafflor yellow A (HSYA), a major active chemical component isolated from Carthamus tinctorius L., has been shown to possess neuroprotective actions in various ischemic models in vivo. The present study aimed to investigate the potential protective effect of HSYA against Aβ-induced neurotoxicity in cultured rat pheochromocytoma (PC12) cells. The PC12 cells were pretreated with different concentrations (20, 40 and 80 μM) of HSYA for 2 h and then further treated with Aβ (20 μM) for 24 h. The results showed that Aβ could significantly decrease cell viability, glutathione level, mitochondrial membrane potential and the ratio of Bcl-2/Bax protein expression, while elevate the release of lactate dehydrogenase, the formation of DNA fragmentation, the levels of malondialdehyde and intracellular reactive oxygen species in PC12 cells. However, pretreatment with HSYA could effectively reverse these changes induced by Aβ in PC12 cells. Our experimental results demonstrate that HSYA may be a potential neuroprotective agent warranting further development for treatment of AD.
    Neurochemical Research 02/2013; · 2.13 Impact Factor
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    ABSTRACT: The neurotoxicity of amyloid- β (A β ) has been implicated as a critical cause of Alzheimer's disease. Isorhynchophylline (IRN), an oxindole alkaloid isolated from Uncaria rhynchophylla, exerts neuroprotective effect against Aβ 25-35-induced neurotoxicity in vitro. However, the exact mechanism for its neuroprotective effect is not well understood. The present study aimed to investigate the molecular mechanisms underlying the protective action of IRN against Aβ 25-35-induced neurotoxicity in cultured rat pheochromocytoma (PC12) cells. Pretreatment with IRN significantly increased the cell viability, inhibited the release of lactate dehydrogenase and the extent of DNA fragmentation in Aβ 25-35-treated cells. IRN treatment was able to enhance the protein levels of phosphorylated Akt (p-Akt) and glycogen synthase kinase-3 β (p-GSK-3 β ). Lithium chloride blocked Aβ 25-35-induced cellular apoptosis in a similar manner as IRN, suggesting that GSK-3 β inhibition was involved in neuroprotective action of IRN. Pretreatment with LY294002 completely abolished the protective effects of IRN. Furthermore, IRN reversed Aβ 25-35-induced attenuation in the level of phosphorylated cyclic AMP response element binding protein (p-CREB) and the effect of IRN could be blocked by the PI3K inhibitor. These experimental findings unambiguously suggested that the protective effect of IRN against Aβ 25-35-induced apoptosis in PC12 cells was associated with the enhancement of p-CREB expression via PI3K/Akt/GSK-3 β signaling pathway.
    Evidence-based Complementary and Alternative Medicine 01/2013; 2013:163057. · 1.72 Impact Factor
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    ABSTRACT: Cortex Phellodendron chinensis (CPC) and Cortex Phellodendron amurensis (CPA) derived from the dried bark of Phellodendron chinense Schneid. or Phellodendron amurense Rupr., respectively, are used interchangeably in clinical practice under the name "Huang Bai" for centuries in Chinese medicine for the treatment of various inflammatory conditions. Previous study in our laboratory demonstrated that CPC and CPA had different anti-diarrheal, anti-bacterial and anti-inflammatory effects. In this present study, we aimed to compare the protective effect of ethanol extract of Cortex Phellodendri chinensis (ECPC) and Cortex Phellodendri Amurensis (ECPA) against beta-amyloid (Aβ)-induced neurotoxicity in PC12 cells, a typical model of Alzheimer's disease. The results showed that ECPC and ECPA contain four common chemical markers such as berberine, but palmatine and jatrorrhizin were not found in CPC in contrast to the presence in CPA. In addition, both ECPC and ECPA can significantly increase the cell viability in Aβ-treated PC12 cells. Moreover, ECPC and ECPA can markedly elevate the ratio of the protein and mRNA levels of Bcl-2/Bax, while remarkably decrease the release of cytochrome c, and the protein and mRNA expression of caspase-3. Interestingly, ECPA has better protective effect than ECPC against Aβ-induced neurotoxicity in PC12 cells. These results indicate that both ECPC and ECPA have potential protective effect against Aβ-induced neurotoxicity in PC12 cells, and ECPA is more potential of the two species to be used in traditional medicine as a neuroprotective agent for the treatment of AD. The neuroprotective effect of the two species may be mediated, at least in part, via suppressing of the cellular apoptosis.
    Phytomedicine: international journal of phytotherapy and phytopharmacology 11/2012; · 2.97 Impact Factor
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    ABSTRACT: Rhizoma Polygonati is originated from the dried rhizomes of Polygonatum sibircum Red. It has long been used in traditional Chinese medicine for the treatment of inflammatory disorders. The present study aims to investigate the anti-inflammatory effect of aqueous extract of Rhizoma Polygonati (ERP) in a mouse model of inflammation induced by 12-O-tetradecanoylphorbol-acetate (TPA). The anti-inflammatory effect was evaluated by measuring the ear thickness and activity of myeloperoxidase (MPO). The anti-inflammatory mechanism was explored by determining the protein and mRNA levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6. The results showed that ERP significantly decreased the ear thickness and MPO activity in mouse model of inflammation induced by TPA. In addition, ERP also remarkably inhibited the protein and mRNA levels of iNOS, COX-2, TNF-α, IL-1β, and IL-6. These results indicate that ERP has potential anti-inflammatory effect on TPA-induced inflammatory in mice, and the anti-inflammatory effect may be mediated, at least in part, by inhibiting the mRNA expression of a panel of inflammatory mediators including iNOS, COX-2, TNF-α, IL-1β, and IL-6.
    Journal of ethnopharmacology 06/2012; 142(3):851-6. · 2.32 Impact Factor
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    ABSTRACT: Beta-Amyloid peptide (Aβ), a major protein component of brain senile plaques in Alzheimer's disease (AD), has been considered as a critical cause in the pathogenesis of AD. Pinostrobin, a potent flavonoid inducer, is the major and most active ingredient of Folium cajani. The present study aimed to investigate whether pinostrobin could provide protective effect against Aβ(25-35)-induced neurotoxicity in cultured rat pheochromocytoma (PC12) cells. The PC12 cells were pretreated with different concentrations of pinostrobin for 2 h, followed by the challenge with 20 μM Aβ(25-35) for 24 h. The results showed that pretreatment with pinostrobin significantly elevated cell viability, decreased the lactate dehydrogenase activity, the levels of intracellular reactive oxygen species and calcium, and mitochondrial membrane potential in Aβ(25-35)-treated PC12 cells. In addition, pinostrobin significantly suppressed the formation of DNA fragmentation and increased the ratio of Bcl-2/Bax. These results indicate that pinostrobin was able to exert a neuroprotective effect against Aβ(25-35)-induced neurotoxicity in PC12 cells, at least in part, via inhibiting oxidative damage and calcium overload, as well as suppressing the mitochondrial pathway of cellular apoptosis.
    Cellular and Molecular Neurobiology 05/2012; · 2.29 Impact Factor
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    ABSTRACT: Visceral hypersensitivity is an important characteristic feature of functional gastrointestinal disorders, such as irritable bowel syndrome (IBS). This study evaluated the effect of Schisandra chinensis on visceral hyperalgesia induced by neonatal maternal separation (NMS) in an IBS rat model. The visceromotor responses to colorectal balloon distension (CRD) were measured by abdominal withdrawal reflex (AWR) and electromyographic (EMG) activities. NMS control rats (receiving vehicle) underwent aggravated visceral pain in response to CRD as compared to normal rats, evidenced by the reduced pain threshold, enhanced AWR scores and EMG responses. Treatment with a 70% ethanol extract of S. chinensis (0.3g/kg and 1.5g/kg/day) for 7 days resulted in an increase in the pain threshold (NMS control: 19.1±1.0mmHg vs low-dose: 24.8±1.3mmHg and high-dose: 25.2±1.8mmHg, p<0.01), and abolished the elevated AWR and EMG responses to CRD in NMS rats (AUC values of EMG response curve were: 1952±202 in NMS control group vs 1074±90 in low-dose group and 1145±92 in high-dose group, p<0.001), indicating that S. chinensis could reverse the visceral hypersensitivity induced by early-life stress event. The result of ELSA measurement shows that the elevated serotonin (5-HT) level in the distal colon of NMS rats returned to normal level after treatment with S. chinensis. Moreover, the increase in pain threshold in rats treated with S. chinensis was associated with a decline of the mRNA level of 5-HT(3) receptor in the distal colon. All available results demonstrate that S. chinensis can reverse visceral hypersensitivity induced by neonatal-maternal separation, and the effect may be mediated through colonic 5-HT pathway in the rat.
    Phytomedicine: international journal of phytotherapy and phytopharmacology 03/2012; 19(5):402-8. · 2.97 Impact Factor
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    ABSTRACT: Depression is a common psychiatric disorder, yet the clinical efficacy of antidepression therapies is unsatisfactory. Thus, the search for new anti-depressants continues, and natural products remain a promising source of new therapeutic agents. The root part of Paeonia lactiflora Pall. (Ranunculaceae), known as peony, is often used in Chinese herbal prescriptions for the treatment of depression-like disorders. The objective of this review is to provide scientific evidence to support further research on peony as a potential anti-depressant drug. This review summarizes the results obtained in our laboratory, together with other literature data obtained through a comprehensive search in databases including PubMed, ScienceDirect, Scirus, and Web of Science. The peony extract is active in the mouse forced swim test and tail suspension test, and it produces anti-depressant effects in chronic unpredictable mild stress-induced depression model in mice and rats. The anti-depressant mechanisms of peony are likely mediated by the inhibition of monoamine oxidase activity, neuro-protection, modulation of the function of hypothalamic-pituitary-adrenal axis, inhibition of oxidative stress, and the up-regulation of neurotrophins. Peony is used clinically to treat depression-like symptoms in Chinese medicine, and it has been shown to possess anti-depressant property in a battery of test models using laboratory animals. Its effect is likely mediated by multiple targets. Further studies are warranted to delineate the molecular mechanisms of action, determine the pharmacokinetics, establish the toxicological profile, and assess the potentials of peony in clinical applications. Identification of the clinically active ingredient(s) is also warranted.
    Pharmaceutical Biology 01/2012; 50(1):72-7. · 1.21 Impact Factor
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    ABSTRACT: Uncaria rhynchophylla is a component herb of many Chinese herbal formulae for the treatment of neurodegenerative diseases. Previous study in our laboratory has demonstrated that an ethanol extract of Uncaria rhynchophylla ameliorated cognitive deficits in a mouse model of Alzheimer's disease induced by D-galactose. However, the active ingredients of Uncaria rhynchophylla responsible for the anti-Alzheimer's disease activity have not been identified. This study aims to identify the active ingredients of Uncaria rhynchophylla by a bioassay-guided fractionation approach and explore the acting mechanism of these active ingredients by using a well-established cellular model of Alzheimer's disease, beta-amyloid- (Aβ-) induced neurotoxicity in PC12 cells. The results showed that six alkaloids, namely, corynoxine, corynoxine B, corynoxeine, isorhynchophylline, isocorynoxeine, and rhynchophylline were isolated from the extract of Uncaria rhynchophylla. Among them, rhynchophylline and isorhynchophylline significantly decreased Aβ-induced cell death, intracellular calcium overloading, and tau protein hyperphosphorylation in PC12 cells. These results suggest that rhynchophylline and isorhynchophylline are the major active ingredients responsible for the protective action of Uncaria rhynchophylla against Aβ-induced neuronal toxicity, and their neuroprotective effect may be mediated, at least in part, by inhibiting intracellular calcium overloading and tau protein hyperphosphorylation.
    Evidence-based Complementary and Alternative Medicine 01/2012; 2012:802625. · 1.72 Impact Factor
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    ABSTRACT: Hyperactivation of the hypothalamic-pituitary-adrenal axis and the associated hippocampal atrophy were observed in patients with depression, which could be ameliorated by the treatment with antidepressants. Therefore, neuroprotection has been proposed to be one of the acting mechanisms of antidepressant. Our previous studies have showed that treating mice with piperine produced antidepressant-like effect in animal models of behavioral despair. This study aimed to examine the protective effect of piperine treatment on corticosterone-induced neurotoxicity in cultured rat pheochromocytoma (PC12) cells. The results showed that piperine co-treatment revealed a differential effect on the cytotoxicity of corticosterone and had its maximum inhibitory effect at 1 μM. Piperine (1 μM) co-treatment also significantly decreased intracellular reactive oxygen species level, and enhanced superoxide dismutase activity and total glutathione level in corticosterone-treated PC12 cells. In addition, piperine (1 μM) co-treatment was found to reverse the decreased brain-derived neurotrophic factor (BDNF) mRNA level caused by corticosterone in PC12 cells. The results suggest that piperine exerts a neuroprotective effect on corticosterone-induced neurotoxicity in PC12 cells, at least in part, via the inhibition of oxidative stress and the upregulation of BDNF mRNA expression. This neuroprotective effect may be one of the acting mechanisms accounts for the in vivo antidepressant activity of piperine.
    Cellular and Molecular Neurobiology 12/2011; 32(4):531-7. · 2.29 Impact Factor
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    ABSTRACT: Repeated injections of corticosterone (CORT) induce the dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, resulting in depressive-like behavior. This study aimed to examine the antidepressant-like effect and the possible mechanisms of total glycosides of peony (TGP) in the CORT-induced depression model in rats. The results showed that the 3-week CORT injections induced the significant increase in serum CORT levels in rats. Repeated CORT injections also caused depression-like behavior in rats, as indicated by the significant decrease in sucrose consumption and increase in immobility time in the forced swim test. Moreover, it was found that brain-derived neurotrophic factor (BDNF) protein levels in the hippocampus and frontal cortex were significantly decreased in CORT-treated rats. Treatment of the rats with TGP significantly suppressed the depression-like behavior and increased brain BDNF levels in CORT-treated rats. The results suggest that TGP produces an antidepressant-like effect in CORT-treated rats, which is possibly mediated by increasing BDNF expression in the hippocampus and frontal cortex.
    Behavioural brain research 11/2011; 227(1):305-9. · 3.22 Impact Factor
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    ABSTRACT: Beta-amyloid peptide (Aβ), a major protein component of senile plaques, has been considered as a critical cause in the pathogenesis of Alzheimer's disease (AD). Modulation of the Aβ-induced neurotoxicity has emerged as a possible therapeutic approach to ameliorate the onset and progression of AD. The present study aimed to evaluate the protective effect of isorhynchophylline, an oxindole alkaloid isolated from a Chinese herb Uncaria rhynchophylla, on Aβ-induced neurotoxicity in cultured rat pheochromocytoma (PC12) cells. The results showed that pretreatment with isorhynchophylline significantly elevated cell viability, decreased the levels of intracellular reactive oxygen species and malondialdehyde, increased the level of glutathione, and stabilized mitochondrial membrane potential in Aβ(25-35)-treated PC12 cells. In addition, isorhynchophylline significantly suppressed the formation of DNA fragmentation and the activity of caspase-3 and moderated the ratio of Bcl-2/Bax. These results indicate that isorhynchophylline exerts a neuroprotective effect against Aβ(25-35)-induced neurotoxicity in PC12 cells, at least in part, via inhibiting oxidative stress and suppressing the mitochondrial pathway of cellular apoptosis.
    Cellular and Molecular Neurobiology 11/2011; 32(3):353-60. · 2.29 Impact Factor