Action Of Berberine Research Articles

Berberine Improves Intestinal Motility and Visceral Pain in the Mouse Models Mimicking Diarrhea-Predominant Irritable Bowel Syndrome (IBS-D) Symptoms in an Opioid-Receptor Dependent Manner.

Background and AimsBerberine and its derivatives display potent analgesic, anti-inflammatory and anticancer activity. Here we aimed at characterizing the mechanism of action of berberine in the gastrointestinal (GI) tract and cortical neurons using animal models and in vitro tests.MethodsThe effect of berberine was characterized in murine models mimicking diarrhea-predominant irritable bowel syndrome (IBS-D) symptoms. Then the opioidantagonists were used to identify the receptors involved. Furthermore, the effect of berberineon opioid receptors expression was established in the mouse intestine and rat fetal cortical neurons.ResultsIn mouse models, berberine prolonged GI transit and time to diarrhea in a dose-dependent manner, and significantly reduced visceral pain. In physiological conditions the effects of berberine were mediated by mu- (MOR) and delta- (DOR) opioidreceptors; hypermotility, excessive secretion and nociception were reversed by berberine through MOR and DOR-dependent action. We also found that berberine increased the expression of MOR and DOR in the mouse bowel and rat fetal cortical neurons.ConclusionBerberine significantly improved IBS-D symptoms in animal models, possibly through mu- and delta- opioid receptors. Berberine may become a new drug candidate for the successful treatment of IBS-D in clinical conditions.

ANTITUMOR ACTIVITY OF BERBERINE AGAINST BREAST CANCER: A REVIEW

As the prevalence of breast cancer has been increasing day by day in almost every part of the world, there is need to develop alterna tive therapeutic measures for breast cancer control. To fulfill this need, chemoprevention is a novel approach. E fforts have been made to identify synthetic or natural products that can prevent the pre - neoplastic events preceding the occurrence of detectab le cancer. Berberine (quaternary ammonium salt from the protoberberine group of isoquinoline alkaloids) is one such compound . In this review in vitro and in vivo anticancer activities of berberine have been summarized . The m echanisms of action of berberine include ; inhibition of tumorigenic microorganisms, regulation of oncogene, interaction with DNA and RNA, inhibition of carcinogenesis related enzymes and induction of apoptosis. Berbrine has synergistic activity of when given in combined medication while it is also responsible for reduction of multidrug resistance in breast cancer treatment.

Berberine protects against neuronal damage via suppression of glia-mediated inflammation in traumatic brain injury.

Traumatic brain injury (TBI) triggers a series of neuroinflammatory processes that contribute to evolution of neuronal injury. The present study investigated the neuroprotective effects and anti-inflammatory actions of berberine, an isoquinoline alkaloid, in both in vitro and in vivo TBI models. Mice subjected to controlled cortical impact injury were injected with berberine (10 mg·kg−1) or vehicle 10 min after injury. In addition to behavioral studies and histology analysis, blood-brain barrier (BBB) permeability and brain water content were determined. Expression of PI3K/Akt and Erk signaling and inflammatory mediators were also analyzed. The protective effect of berberine was also investigated in cultured neurons either subjected to stretch injury or exposed to conditioned media with activated microglia. Berberine significantly attenuated functional deficits and brain damage associated with TBI up to day 28 post-injury. Berberine also reduced neuronal death, apoptosis, BBB permeability, and brain edema at day 1 post-injury. These changes coincided with a marked reduction in leukocyte infiltration, microglial activation, matrix metalloproteinase-9 activity, and expression of inflammatory mediators. Berberine had no effect on Akt or Erk 1/2 phosphorylation. In mixed glial cultures, berberine reduced TLR4/MyD88/NF-κB signaling. Berberine also attenuated neuronal death induced by microglial conditioned media; however, it did not directly protect cultured neurons subjected to stretch injury. Moreover, administration of berberine at 3 h post-injury also reduced TBI-induced neuronal damage, apoptosis and inflammation in vivo. Berberine reduces TBI-induced brain damage by limiting the production of inflammatory mediators by glial cells, rather than by a direct neuroprotective effect.

Berberine attenuates adverse left ventricular remodeling and cardiac dysfunction after acute myocardial infarction in rats: role of autophagy.

The present study aimed to test the hypothesis that berberine, a plant-derived anti-oxidant, attenuates adverse left ventricular remodelling and improves cardiac function in a rat model of myocardial infarction (MI). Furthermore, the potential mechanisms that mediated the cardioprotective actions of berberine, in particular the effect on autophagy, were also investigated. Acute MI was induced by ligating the left anterior descending coronary artery of Sprague-Dawley rats. Cardiac function was assessed by transthoracic echocardiography. The protein activity/levels of autophagy related to signalling pathways (e.g. LC-3B, Beclin-1) were measured in myocardial tissue by immunohistochemical staining and western blot. Four weeks after MI, berberine significantly prevented cardiac dysfunction and adverse cardiac remodelling. MI rats treated with low dose berberine (10 mg/kg per day) showed higher left ventricular ejection fraction and fractional shortening than those treated with high-dose berberine (50 mg/kg per day). Both doses reduced interstitial fibrosis and post-MI adverse cardiac remodelling. The cardioprotective action of berberine was associated with increased LC-3B II and Beclin-1 expressions. Furthermore, cardioprotection with berberine was potentially related to p38 MAPK inhibition and phospho-Akt activation. The present in vivo study showed that berberine is effective in promoting autophagy, and subsequently attenuating left ventricular remodelling and cardiac dysfunction after MI. The potential underlying mechanism is augmentation of autophagy through inhibition of p38 MAPK and activation of phospho-Akt signalling pathways.

Uncoupling protein‐2 mediates the protective action of berberine against oxidative stress in rat insulinoma INS‐1E cells and in diabetic mouse islets

Uncoupling protein-2 (UCP2) may regulate glucose-stimulated insulin secretion. The current study investigated the effects of berberine, an alkaloid found in many medicinal plants, on oxidative stress and insulin secretion through restoration of UCP2 expression in high glucose (HG)-treated INS-1E cells and rat islets or in db/db mouse islets. Mouse and rat pancreatic islets were isolated. Nitrotyrosine, superoxide dismutase (SOD)-1 and UCP2 expression and AMPK phosphorylation were examined by Western blotting. Insulin secretion was measured by ELISA. Mitochondrial reactive oxygen species (ROS) production was detected by confocal microscopy. Incubation of INS-1E cells and rat islets with HG (30 mmol·L(-1); 8 h) elevated nitrotyrosine level, reduced SOD-1 and UCP2 expression and AMPK phosphorylation, and inhibited glucose-stimulated insulin secretion. HG also increased mitochondrial ROS in INS-1E cells. Co-treatment with berberine inhibited such effects. The AMPK inhibitor compound C, the UCP2 inhibitor genipin and adenovirus ucp2 shRNA inhibited these protective effects of berberine. Furthermore, compound C normalized berberine-stimulated UCP2 expression but genipin did not affect AMPK phosphorylation. Islets from db/db mice exhibited elevated nitrotyrosine levels, reduced expression of SOD-1 and UCP2 and AMPK phosphorylation, and decreased insulin secretion compared with those from db/m(+) mice. Berberine also improved these defects in diabetic islets and genipin blocked the effects of berberine. Berberine inhibited oxidative stress and restored insulin secretion in HG-treated INS-IE cells and diabetic mouse islets by activating AMPK and UCP2. UCP2 is an important signalling molecule in mediating anti-diabetic effects of berberine.

Berberine decreases cholesterol levels in rats through multiple mechanisms, including inhibition of cholesterol absorption

ObjectiveThe objective was to determine the mechanisms of action of berberine (BBR) on cholesterol homeostasis using in vivo and in vitro models. MethodsMale Sprague–Dawley rats were fed the AIN-93G diet (normal control) or modified AIN-93G diet containing 28% fat, 2% cholesterol and 0.5% cholic acid with treatment of 0 (atherogenic control), 50, 100, and 150mg/kg·d of BBR, respectively by gavaging in water for 8weeks. Cholesterol absorption rate was measured with the dual stable isotope ratio method, and plasma lipids were determined using the enzymatic methods. Gene and protein expressions of Acyl-coenzyme A:cholesterol acyltransferase-2 were analyzed in vivo and in vitro. Cholesterol micellarization, uptake and permeability were determined in vitro. ResultsRats on the atherogenic diet showed significantly hypercholesterolemic characteristics compared to normal control rats. Treatment with BBR in rats on the atherogenic diet reduced plasma total cholesterol and nonHDL cholesterol levels by 29%–33% and 31%–41%, respectively, with no significant differences being observed among the three doses. The fractional dietary cholesterol absorption rate was decreased by 40%–51%. Rats fed the atherogenic diet showed lower plasma triacylglycerol levels, and no changes were observed after the BBR treatment. BBR interfered with cholesterol micellarization, decreased cholesterol uptake by Caco-2 cells and permeability through Caco-2 monolayer. BBR also inhibited the gene and protein expressions of acyl-coenzyme A cholesterol acyltransferease-2 in the small intestine and Caco-2 cells. ConclusionBBR lowered blood cholesterol levels at least in part through inhibiting the intestinal absorption and further by interfering with intraluminal cholesterol micellarization and decreasing enterocyte cholesterol uptake and secretion.

Effects of berberine in the gastrointestinal tract - a review of actions and therapeutic implications.

Berberine is an isoquinoline alkaloid present in several plant species, including Coptis sp. and Berberis sp. In traditional medicine, extracts of berberine are used in the treatment of diarrhea of different origins. Recent studies have shown that berberine and its derivatives have significant biological effects on gastrointestinal (GI) and other functions and may become therapeutics for the treatment of diarrhea, gastroenteritis, diabetes, hyperlipidemia, cardiovascular diseases and inflammatory conditions. This paper summarizes the current knowledge on the actions of berberine in the GI tract. Binding and target sites, activated intracellular pathways, as well as the absorption and metabolism of berberine are discussed. Effects that may be useful in future clinical treatment, like antidiarrheal, anti-inflammatory and antitumor effects are critically reviewed and potential clinical applications are presented in detail.

Inhibition of organic cation transporter 2 and 3 may be involved in the mechanism of the antidepressant-like action of berberine

Organic cation transporter 2 (OCT2) and 3 (OCT3) are low-affinity, high-capacity transporters (uptake-2) expressed in the central nervous system (CNS) and other major organs. Proven to be essential components in the CNS functions, OCT2 and OCT3 are suggested as potential targets of antidepressant therapeutics recently. Berberine, an active constituent derived from many medicinal plants, such as Coptis chinensis, has been reported to possess antidepressant-like action in the tail suspension test and forced swim test with elevated serotonin/norepinephrine/dopamine (5-HT/NE/DA) level in mouse brain; however the mechanism has not been elucidated. In consideration of the relation between OCT2/3 and antidepressant action, and the characteristic of berberine as an organic cation, we investigated the potential involvement of OCT2 and OCT3 in the antidepressant-like action of berberine in the present study. The results in mouse brain synaptosomes demonstrated that uptake-2 inhibition might play a notable role in enhanced serotonergic and noradrenergic effects induced by berberine. The inhibitory study in transfected MDCK cells displayed that berberine is a potent inhibitor of human OCT2 and OCT3, and its IC50 values for inhibition of transporter-mediated 5-HT/NE uptake are between 0.1 and 1μM. In addition, berberine was identified as a substrate of hOCT2 and hOCT3. In conclusion, berberine is a substrate and an inhibitor of hOCT2 and hOCT3, and its inhibition on OCT2- and OCT3-mediated 5-HT and NE uptake may contribute to the enhanced monoamine neurotransmission in mouse brain. It was deduced that the inhibition of OCT2 and OCT3 probably be implicated in the mechanism of antidepressant-like action.

Genomic Screening for Targets Regulated by Berberine in Breast Cancer Cells

Berberine, a common isoquinoline alkaloid, has been shown to possess anti-cancer activities. However, the underlying molecular mechanisms are still not completely understood. In the current study, we investigated the effects of berberine on cell growth, colony formation, cell cycle distribution, and whether it improved the anticancer efficiency of cisplatin and doxorubicin in human breast cancer estrogen receptor positive (ER+) MCF-7 cells and estrogen receptor negative (ER-) MDA-MB-231 cells. Notably, berberine treatment significantly inhibited cell growth and colony formation in the two cell lines, berberine in combination with cisplatin exerting synergistic growth inhibitory effects. Accompanied by decreased growth, berberine induced G1 phase arrest in MCF-7 but not MDA-MB-231 cells. To provide a more detailed understanding of the mechanisms of action of berberine, we performed genome-wide expression profiling of berberine-treated cells using cDNA microarrays. This revealed that there were 3,397 and 2,706 genes regulated by berberine in MCF-7 and MDA-MB-231 cells, respectively. Fene oncology (GO) analysis identified that many of the target genes were involved in regulation of the cell cycle, cell migration, apoptosis, and drug responses. To confirm the microarray data, qPCR analysis was conducted for 10 selected genes based on previously reported associations with breast cancer and GO analysis. In conclusion, berberine exhibits inhibitory effects on breast cancer cells proliferation, which is likely mediated by alteration of gene expression profiles.

Berberine Inhibits the Release of Glutamate in Nerve Terminals from Rat Cerebral Cortex

Berberine, an isoquinoline plant alkaloid, protects neurons against neurotoxicity. An excessive release of glutamate is considered to be one of the molecular mechanisms of neuronal damage in several neurological diseases. In this study, we investigated whether berberine could affect endogenous glutamate release in nerve terminals of rat cerebral cortex (synaptosomes) and explored the possible mechanism. Berberine inhibited the release of glutamate evoked by the K+ channel blocker 4-aminopyridine (4-AP), and this phenomenon was prevented by the chelating extracellular Ca2+ ions and the vesicular transporter inhibitor bafilomycin A1, but was insensitive to the glutamate transporter inhibitor DL-threo-beta-benzyl-oxyaspartate. Inhibition of glutamate release by berberine was not due to it decreasing synaptosomal excitability, because berberine did not alter 4-AP-mediated depolarization. The inhibitory effect of berberine on glutamate release was associated with a reduction in the depolarization-induced increase in cytosolic free Ca2+ concentration. Involvement of the Cav2.1 (P/Q-type) channels in the berberine action was confirmed by blockade of the berberine-mediated inhibition of glutamate release by the Cav2.1 (P/Q-type) channel blocker ω-agatoxin IVA. In addition, the inhibitory effect of berberine on evoked glutamate release was prevented by the mitogen-activated/extracellular signal-regulated kinase kinase (MEK) inhibitors. Berberine decreased the 4-AP-induced phosphorylation of extracellular signal-regulated kinase 1 and 2 (ERK1/2) and synapsin I, the main presynaptic target of ERK; this decrease was also blocked by the MEK inhibition. Moreover, the inhibitory effect of berberine on evoked glutamate release was prevented in nerve terminals from mice lacking synapsin I. Together, these results indicated that berberine inhibits glutamate release from rats cortical synaptosomes, through the suppression of presynaptic Cav2.1 channels and ERK/synapsin I signaling cascade. This finding may provide further understanding of the mode of berberine action in the brain and highlights the therapeutic potential of this compound in the treatment of a wide range of neurological disorders.

Calmodulin as a Potential Target by Which Berberine Induces Cell Cycle Arrest in Human Hepatoma Bel7402 Cells

Berberine is an isoquinoline alkaloid that has drawn extensive attention because it possesses various biological activities. Several mechanisms have been proposed to interpret the anticancer activity of berberine. However, these explanations are mostly based on its downstream-regulated genes or proteins; information on the direct target proteins that mediate the antiproliferative action of berberine remains unclear. In this study, a computational pipeline based on a ligand-protein inverse docking program and mining of the 'Connectivity MAP' data was adopted to explore the potential target proteins for berberine. The results showed that four proteins, that is calmodulin, cytochrome P450 3A4, sex hormone-binding globulin, and carbonic anhydrase II, were suggested to be the potential targets of berberine. The anticalmodulin property of berberine was demonstrated with an in vitro phosphodiesterase activity assay. Flow cytometric analysis found that G1 cell cycle arrest induced by berberine in Bel7402 cells was enhanced by cotreatment with calmodulin inhibitors. Western blotting results indicated that berberine treatment decreased phosphorylation of calmodulin kinase II and blocked subsequent MEK1 activation as well as p27 protein degradation. These results suggested that calmodulin might play crucial roles in berberine-induced cell cycle arrest in cancer cells.

Amelioration of IFN-γ and TNF-α-Induced Intestinal Epithelial Barrier Dysfunction by Berberine via Suppression of MLCK-MLC Phosphorylation Signaling Pathway

Intestinal barrier dysfunction occurs in many intestinal diseases, in which proinflammatory cytokines play critical roles. However, researchers are still on the way to defining the underlying mechanisms and to evaluate therapeutic strategies for restoring intestinal barrier function. Berberine, a drug that has clinically been used to treat gastroenteritis and diarrhea for thousands of years, has been shown to protect barrier function in both endothelial and epithelial cells, but the mechanisms are completely unknown. In this study, we investigate the protective actions of berberine on barrier function and the underlying mechanisms in Caco-2 monolayers challenged with IFN-γ and TNF-α. Caco-2 monolayers were treated without or with simultaneous IFN-γ and TNF-α in the absence or presence of berberine. Both transepithelial electrical resistance (TER) and paracellular permeability were measured to evaluate barrier function. The expression and distribution of tight junction proteins ZO-1, occluding, and claudin-1 were respectively analyzed by immunoblot or immunofluorescence. The expressions of phosphorylated myosin light chain (pMLC), MLC kinase (MLCK) and hypoxia-inducible factor-1α (HIF-1α) were determined by immunoblot. The translocation of NF-κB p65 to nuclei was analyzed by immunofluorescence and immunoblot, respectively. The results showed that berberine significantly attenuated TER decrease and paracellular permeability increase in Caco-2 monolayers treated with IFN-γ and TNF-α. Berberine also dramatically alleviated IFN-γ and TNF-α-induced morphological alteration of tight junction proteins ZO-1, occluding, and claudin-1. The increase of both MLC phosphorylation and MLCK protein expression induced by IFN-γ and TNF-α was significantly inhibited by berberine treatment. Additionally, berberine suppressed the activation of HIF-1α, but not NF-κB. Taken together, it is suggested that berberine attenuates IFN-γ and TNF-α-induced intestinal epithelial barrier dysfunction by inhibiting the signaling pathway of MLCK-dependent MLC phosphorylation mediated by HIF-1α.

Berberine inhibits mouse insulin gene promoter through activation of AMP activated protein kinase and may exert beneficial effect on pancreatic β-cell

Berberine is one of the main alkaloids of Rhizoma coptidis, proven to have anti-diabetic potentials through activation of AMP activated protein kinase (AMPK) in liver and muscle. However, the role of berberine on the insulin gene is unknown. Therefore, the effect of berberine on insulin gene transcription was investigated in the present study. Reporter gene assays were used in the mouse β-cell line NIT-1 to test the effect of berberine on the promoter of mouse insulin gene Ins2. The mRNA and protein levels of insulin were also detected. Diet induced glucose intolerant mice were used to explore the effect of berberine on blood glucose homeostasis and insulin resistance in vivo. The insulin content in islet was semi-quantified by an image analysis software in the immunohistochemistry sections. The results revealed that berberine caused a reversible concentration-dependent inhibition of insulin gene transcription in NIT-1 cells which showed a significant difference from the long term used AMPK activator metformin. Such inhibition on insulin promoter resulted in the reduction of mRNA and protein of insulin. Furthermore, the inhibition of insulin promoter was totally abolished by AMPK inhibitor Compound C. Berberine significantly improved insulin resistance and glucose intolerance of mice. Likewise, insulin content in islets of berberine treated mice was also decreased. Thus, the insulin gene represents a novel target of AMPK that may contribute to the action of berberine in type 2 diabetes mellitus.

Up-Regulating Relaxin Expression by G-Quadruplex Interactive Ligand to Achieve Antifibrotic Action

Myocardial fibrosis is a key pathological change in a variety of heart diseases contributing to the development of heart failure, arrhythmias, and sudden death. Recent studies have shown that relaxin prevents and reverses cardiac fibrosis. Endogenous expression of relaxin was elevated in the setting of heart disease; the extent of such up-regulation, however, is insufficient to exert compensatory actions, and the mechanism regulating relaxin expression is poorly defined. In the rat relaxin-1 (RLN1, Chr1) gene promoter region we found presence of repeated guanine (G)-rich sequences, which allowed formation and stabilization of G-quadruplexes with the addition of a G-quadruplex interactive ligand berberine. The G-rich sequences and the G-quadruplexes were localized adjacent to the binding motif of signal transducer and activator of transcription (STAT)3, which negatively regulates relaxin expression. Thus, we hypothesized that the formation and stabilization of G-quadruplexes by berberine could influence relaxin expression. We found that berberine-induced formation of G-quadruplexes did increase relaxin gene expression measured at mRNA and protein levels. Formation of G-quadruplexes significantly reduced STAT3 binding to the promoter of relaxin gene. This was associated with consequent increase in the binding of RNA polymerase II and STAT5a to relaxin gene promoter. In cardiac fibroblasts and rats treated with angiotensin II, berberine was found to suppress fibroblast activation, collagen synthesis, and extent of cardiac fibrosis through up-regulating relaxin. The antifibrotic action of berberine in vitro and in vivo was similar to that by exogenous relaxin. Our findings document a novel therapeutic strategy for fibrosis through up-regulating expression of endogenous relaxin.

Berberine ameliorates inflammation in patients with acute coronary syndrome following percutaneous coronary intervention

1. Inflammation is central to the pathogenesis of acute coronary syndrome (ACS) and is associated with adverse clinical outcomes after percutaneous coronary intervention (PCI). Recent in vitro work has demonstrated the anti-inflammatory effect of berberine, a primary component of the traditional Chinese medicine 'umbellatine'. In the present study, we further tested whether berberine had any beneficial effects on ACS patients following PCI. 2.In all, 130 ACS patients undergoing PCI were recruited to the present study. Sixty-one patients were treated with berberine (300mg, t.i.d., for 30days) in addition to standard therapy, whereas the remaining patients received standard therapy alone. Circulating inflammatory markers were measured by ELISA, whereas serum lipid profiles were measured by routine chemical assays. 3.In the berberine-treated group, matrix metalloproteinase (MMP)-9, intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM)-1, C-reactive protein, interleukin-6 and monocyte chemoattractant protein-1 were significantly reduced relative to baseline values. Furthermore, the changes in MMP-9, ICAM-1 and VCAM-1 from baseline to after 1month of treatment differed significantly between the two patient groups. There was a tendency for berberine to induce a slightly greater reduction in low-density lipoprotein cholesterol and triglycerides than standard therapy alone, without affecting high-density lipoprotein cholesterol, but the differences failed to reach statistical significance. No severe adverse effects of berberine were observed. 4.The results of the present study provide the first clinical evidence of the anti-inflammatory action of berberine in ACS patients following PCI. Berberine may become adjunct therapy to further improve clinical outcomes via its anti-inflammatory effect in ACS patients.

Ameliorative effect of berberine on renal damage in rats with diabetes induced by high-fat diet and streptozotocin

Berberine (BBR) is one of the main constituents in Rhizoma coptidis and it has widely been used for the treatment of diabetic nephropathy. The aims of the study were to investigate the effects and mechanism of action of berberine on renal damage in diabetic rats. Diabetes and hyperglycaemia were induced in rats by a high-fat diet and intraperitoneal injection of 40mg/kg streptozotocin (STZ). Rats were randomly divided into 5 groups, such as i) control rats, ii) untreated diabetic rats iii) 250mg/kg metformin-treated, iv and v) 100 and 200mg/kg berberine-treated diabetic rats and treated separately for 8 weeks. The fasting blood glucose, insulin, total cholesterol, triglyceride, glycosylated hemoglobin were measured in rats. Kidneys were isolated at the end of the treatment for histology, Western blot analysis and estimation of malonaldehyde (MDA), superoxide dismutase (SOD) and renal advanced glycation endproducts (AGEs). The results revealed that berberine significantly decreased fasting blood glucose, insulin levels, total cholesterol, triglyceride levels, urinary protein excretion, serum creatinine (Scr) and blood urea nitrogen (BUN) in diabetic rats. The histological examinations revealed amelioration of diabetes-induced glomerular pathological changes following treatment with berberine. In addition, the protein expressions of nephrin and podocin were significantly increased. It seems likely that in rats berberine exerts an ameliorative effect on renal damage in diabetes induced by high-fat diet and streptozotocin. The possible mechanisms for the renoprotective effects of berberine may be related to inhibition of glycosylation and improvement of antioxidation that in turn upregulate the expressions of renal nephrin and podocin.

Interaction of Herbal Compounds with Biological Targets: A Case Study with Berberine

Berberine is one of the main alkaloids found in the Chinese herb Huang lian (Rhizoma Coptidis), which has been reported to have multiple pharmacological activities. This study aimed to analyze the molecular targets of berberine based on literature data followed by a pathway analysis using the PANTHER program. PANTHER analysis of berberine targets showed that the most classes of molecular functions include receptor binding, kinase activity, protein binding, transcription activity, DNA binding, and kinase regulator activity. Based on the biological process classification of in vitro berberine targets, those targets related to signal transduction, intracellular signalling cascade, cell surface receptor-linked signal transduction, cell motion, cell cycle control, immunity system process, and protein metabolic process are most frequently involved. In addition, berberine was found to interact with a mixture of biological pathways, such as Alzheimer's disease-presenilin and -secretase pathways, angiogenesis, apoptosis signalling pathway, FAS signalling pathway, Hungtington disease, inflammation mediated by chemokine and cytokine signalling pathways, interleukin signalling pathway, and p53 pathways. We also explored the possible mechanism of action for the anti-diabetic effect of berberine. Further studies are warranted to elucidate the mechanisms of action of berberine using systems biology approach.

PI3K p55γ promoter activity enhancement is involved in the anti-apoptotic effect of berberine against cerebral ischemia–reperfusion

Berberine is a candidate clinical neuroprotective agent against ischemic stroke. In the present study, we examined the influence of the PI3K/Akt pathway in mediating the anti-apoptotic effects of berberine. Oxygen–glucose deprivation and reoxygenation of nerve growth factor-differentiated PC12 cells and primary neurons, and bilateral common carotid artery occlusion in mice were used as in vitro and in vivo ischemia models. We found that the anti-apoptotic effects of berberine against ischemia were indeed mediated by the increased phosphor-activation of Akt (higher p-Akt to total Akt), leading to the intensified phosphorylation of Bad and the decreased cleavage of the pro-apoptotic protease caspase-3. Berberine action is specific for PI3K, rather than the upstream receptor tyrosine kinase. The anti-apoptotic effect is maintained in the presence of tyrosine kinase inhibitor genistein and the epidermal growth factor receptor inhibitor PD153035, but is suppressed by the PI3K inhibitor Ly294002 and the Akt inhibitor Akti-1/2.The unique PI3K regulatory subunit p55γ was upregulated by berberine during ischemia–reperfusion and was not blocked by these inhibitors. We constructed a reporter plasmid to detect PI3K p55γ promoter activity and found that berberine enhanced PI3K p55γ promoter activity during cerebral ischemia–reperfusion.

COX-2 and survivin reduction may play a role in berberine-induced apoptosis in human ductal breast epithelial tumor cell line

Berberine is an isoquinoline alkaloid that has several pharmacological effects such as antiinflammatory, antimicrobial, apoptosis-inducing and anticancer effects. It has been illustrated that the antiinflammatory effect is mediated by suppressing the nuclear factor-kappa B (NF-κB) that activates expression of some antiinflammatory and antiapoptotic proteins including cyclooxygenase-2(COX-2), inducible nitric oxide synthase (iNOS) and survivin; therefore, berberine may induce apoptosis by reducing antiinflammatory and antiapoptotic agents, which suggest the relationship between antiinflammatory and apoptosis pathways. For further illustration of the mechanism of berberine action, the human ductal breast epithelial tumor cell line (T47D cell line) was treated with different concentrations of berberine (25-100 μM/ml). Berberine in 50 μM/ml had the most reducing effect on cell viability and inducing of apoptosis. The level of COX-2, iNOS and survivin proteins decreased in berberine-treated cells; however, treatment of the cells with aspirin and aminoguanidine (AG), COX-2 and iNOS inhibitors, respectively, showed that despite the cell growth-reducing effect of aspirin, AG did not have a significant effect on cell viability. On the other hand, with the attention to reduction in survivin protein level in berberine-treated cells, the results suggest that the apoptotic effect of berberine may be mediated by reduction in both of the COX-2 and survivin in T47D cell line, while the iNOS does not play any effective role in berberine-induced apoptosis.

Berberine protects against lipopolysaccharide-induced intestinal injury in mice via alpha 2 adrenoceptor-independent mechanisms

To investigate the mechanisms responsible for the protective action of berberine (Ber) against gut damage in endotoxemic mice. Male BALB/c mice were administered intragastrically with distilled water (0.1 mL/10 g), Ber (50 mg/kg) alone, yohimbine (2 mg/kg) alone, or Ber (50 mg/kg) in combination with yohimbine (2 mg/kg) for 3 d. On the third day, lipopolysaccharide (LPS, 18 mg/kg) or normal saline was intraperitoneally injected one hour after the intragastric administration. Following the treatment, intestinal injury in the ileum was histopathologically accessed; enterocyte apoptosis was examined using TUNEL method; Toll-like receptor 4 (TLR4) mRNA expression was measured using RT-PCR assay; inhibitor protein-κBα (I-κBα) phosphorylation and myeloperoxidase content were examined using Western blloting. The macrophage inflammatory protein-2 (MIP-2) production was measured using ELISA assay. Mice challenged with LPS caused extensive ileum injury, including a significantly increased injury score, decreased intestinal villus height, reduced gut mucosal weight and increased intestinal permeability. Furthermore, LPS significantly induced enterocyte apoptosis, increased TLR4 mRNA expression, I-κBα phosphorylation, MIP-2 production and myeloperoxidase content in the ileum. Pretreatment with Ber significantly alleviated all the alterations in the ileum in the endotoxemic mice. Pretreatment with the α2-adrenoceptor antagonist yohimbine did not block the protective action of Ber against LPS-induced intestinal injury. In addition, treatment with yohimbine alone did not prevent LPS-induced intestinal injury. Pretreatment with Ber provides significant protection against LPS-induced intestinal injury in mice, via reducing enterocyte apoptosis, inhibiting the TLR4-nuclear factor κB-MIP-2 pathway and decreasing neutrophil infiltration that are independent of α2-adrenoceptors.