Inhibitory effects of Zoagumhwan water extract and berberine on angiotensin II-induced monocyte chemoattractant protein (MCP)-1 expression and monocyte adhesion to endothelial cells

Several major herb pairs containing Coptidis rhizoma: a review of key traditional uses, constituents and compatibility effects

Herb compatibility is the soul of traditional Chinese Medicine prescriptions. Coptidis rhizoma (CR) (Coptis chinensis Franch., Coptis deltoidea C.Y.Cheng et Hsiao, or Coptis teeta Wall.; family Ranunculaceae), is a well-known herb. The bitter and cold nature of CR can irritate the spleen and stomach, and certain ingredients in CR may trigger allergic reactions. Herb combinations can help alleviate the side effects caused by CR. Through data analysis and literature research, there are many herbs combined with CR have a high frequency, but only a few are currently used as formulae in clinical practice. The results showed that these six herb pairs are usually widely studied or used as prescriptions in the clinic. This paper describes the six herb pairs from the key traditional uses, changes in bioactive constituents, and compatibility effects, especially with Euodiae fructus (family Rutaceae), Scutellariae radix (family Lamiaceae), Magnoliae Officinalis cortex (family Magnoliaceae), Glycyrrhizae radix et rhizoma (family Fabaceae), Ginseng radix et rhizoma (family Araliaceae), and Aucklandiae radix (family Asteraceae), and found that herbs are more effective when used in combination. Therefore, it is feasible to establish some methods to study herb pairs comprehensively from different perspectives. This paper aims to provide the latest and most comprehensive information on the six herb pairs and summarize the pattern of CR compatibility effects. It aims to attract more attention, and further experimental studies will be conducted to investigate and evaluate the effects of herb pairs containing CR. These data can also provide valuable references for researchers and also provide more possibilities for future applications in clinical practice and new drug development.

Vascular Protective Effect and Its Possible Mechanism of Action on Selected Active Phytocompounds: A Review

Vascular endothelial dysfunction is characterized by an imbalance of vasodilation and vasoconstriction, deficiency of nitric oxide (NO) bioavailability and elevated reactive oxygen species (ROS), and proinflammatory factors. This dysfunction is a key to the early pathological development of major cardiovascular diseases including hypertension, atherosclerosis, and diabetes. Therefore, modulation of the vascular endothelium is considered an important therapeutic strategy to maintain the health of the cardiovascular system. Epidemiological studies have shown that regular consumption of medicinal plants, fruits, and vegetables promotes vascular health, lowering the risk of cardiovascular diseases. This is mainly attributed to the phytochemical compounds contained in these resources. Various databases, including Google Scholar, MEDLINE, PubMed, and the Directory of Open Access Journals, were searched to identify studies demonstrating the vascular protective effects of phytochemical compounds. The literature had revealed abundant data on phytochemical compounds protecting and improving the vascular system. Of the numerous compounds reported, curcumin, resveratrol, cyanidin-3-glucoside, berberine, epigallocatechin-3-gallate, and quercetin are discussed in this review to provide recent information on their vascular protective mechanisms in vivo and in vitro. Phytochemical compounds are promising therapeutic agents for vascular dysfunction due to their antioxidative mechanisms. However, future human studies will be necessary to confirm the clinical effects of these vascular protective mechanisms.

Promising Antioxidative Effect of Berberine in Cardiovascular Diseases

Berberine (BBR), an important quaternary benzylisoquinoline alkaloid, has been used in Chinese traditional medicine for over 3,000 years. BBR has been shown in both traditional and modern medicine to have a wide range of pharmacological actions, including hypoglycemic, hypolipidemic, anti-obesity, hepatoprotective, anti-inflammatory, and antioxidant activities. The unregulated reaction chain induced by oxidative stress as a crucial mechanism result in myocardial damage, which is involved in the pathogenesis and progression of many cardiovascular diseases (CVDs). Numerous researches have established that BBR protects myocardium and may be beneficial in the treatment of CVDs. Given that the pivotal role of oxidative stress in CVDs, the pharmacological effects of BBR in the treatment and/or management of CVDs have strongly attracted the attention of scholars. Therefore, this review sums up the prevention and treatment mechanisms of BBR in CVDs from in vitro, in vivo, and finally to the clinical field trials timely. We summarized the antioxidant stress of BBR in the management of coronary atherosclerosis and myocardial ischemia/reperfusion; it also analyzes the pathogenesis of oxidative stress in arrhythmia and heart failure and the therapeutic effects of BBR. In short, BBR is a hopeful drug candidate for the treatment of CVDs, which can intervene in the process of CVDs from multiple angles and different aspects. Therefore, if we want to apply it to the clinic on a large scale, more comprehensive, intensive, and detailed researches are needed to be carried out to clarify the molecular mechanism and targets of BBR.

Effects of Berberine on Atherosclerosis

Atherosclerosis is an epidemic across the globe[A1], and its morbidity and mortality remain high, involving various complications and poor prognoses. In atherosclerosis, endothelial cells (ECs) dysfunction, vascular smooth muscle cells (VSMCs) migration and proliferation, foam cell formation, and inflammatory cell recruitment contribute to disease progression. Vascular stem cells (VSCs) also play a critical role in the cardiovascular system. Important data showed that the simultaneous increase of proliferation and apoptosis of VSMCs is the main cause of graft vein stenosis, suggesting that inhibition of VSMCs proliferation and apoptosis simultaneously is an important strategy for the treatment of atherosclerotic stenosis. Complementary and alternative medicine use among patients with cardiovascular disease (CVD) is growing. Berberine is an extract of Chinese traditional herbs that is known for its antimicrobial and anti-inflammatory effects in the digestive system. Its underlying anti-CVD mechanisms are currently attracting interest, and its pharmacological actions, such as antioxidation, regulation of neurotransmitters and enzymes, and cholesterol-lowering effects, have been substantiated. Recent studying found that berberine could inhibit both the proliferation and apoptosis of VSMCs induced by mechanical stretch stress simultaneously, which suggests that berberine might be an excellent drug to treat atherosclerosis. This review will focus on the recent progress of the effect of berberine on vascular cells, especially VSMCs, to provide important data and a new perspective for the application of berberine in anti-atherosclerosis.

Atheroprotective Effects and Molecular Mechanism of Berberine

Cardiovascular diseases remain the leading cause of morbidity and mortality worldwide. Atherosclerosis is the main pathological basis of cardiovascular diseases and it is closely associated with hyperlipidemia, endothelial injury, macrophage-derived foam cells formation, proliferation and migration of vascular smooth muscle cells (VSMCs), platelet aggregation, and altered gut microbiota. Various symptomatic treatments, that are currently used to inhibit atherosclerosis, need to be administered in long term and their adverse effects cannot be ignored. Berberine (BBR) has beneficial effects on atherosclerosis through regulating multiple aspects of its progression. This review highlights the recent advances in understanding the anti-atherosclerosis mechanism of BBR. BBR alleviated atherosclerosis by attenuation of dyslipidemia, correction of endothelial dysfunction, inhibition of macrophage inflammation and foam cell formation, activation of macrophage autophagy, regulation of the proliferation and migration of VSMCs, attenuation of platelet aggregation, and modulation of gut microbiota. This review would provide a modern scientific perspective to further understanding the molecular mechanism of BBR attenuating atherosclerosis and supply new ideas for atherosclerosis management.

Berberine Reshapes the Balance of the Local Renin-Angiotensin System by Modulating Autophagy under Metabolic Stress in Pancreatic Islets

Results

Prolonged exposure to palmitate increased the expression of ACE and AngII type 1 receptor (ATR1) and decreased the ACE2 expression, which was partly offset by berberine. In ob/ob mice, berberine increased in tolerance to glucose, improved abnormal β-cell and α-cell distributions, upregulated ACE2 expression, and decreased autophagosomes and the expression of LC3 and SQSTM1/p62. Autophagosomes and expression of LC3 and SQSTM1/p62 were increased in ACE2KO mice.

Conclusions

We demonstrated that berberine may improve the pancreatic islet function by regulating local RAS-mediated autophagy under metabolic stress.

Berberine in Cardiovascular and Metabolic Diseases: From Mechanisms to Therapeutics

Cardiovascular and metabolic diseases (CVMD) are the leading causes of death worldwide, underscoring the urgent necessity to develop new pharmacotherapies. Berberine (BBR) is an eminent component of traditional Chinese and Ayurvedic medicine for more than 2000 years. Recently, BBR has attracted much interest for its pharmacological actions in treating and/or managing CVMD. Recent discoveries of basic, translational and clinical studies have identified many novel molecular targets of BBR (such as AMPK, SIRT1, LDLR, PCSK9, and PTP1B) and provided novel evidences supporting the promising therapeutic potential of BBR to combat CVMD. Thus, this review provides a timely overview of the pharmacological properties and therapeutic application of BBR in CVMD, and underlines recent pharmacological advances which validate BBR as a promising lead drug against CVMD.

Inhibition of Angiotensin Converting Enzyme, Angiotensin II Receptor Blocking, and Blood Pressure Lowering Bioactivity across Plant Families

Hypertension is a major risk factor for coronary heart disease, kidney disease, and stroke. Interest in medicinal or nutraceutical plant bioactives to reduce hypertension has increased dramatically. The main biological regulation of mammalian blood pressure is via the renin-angiotensin-aldosterone system. The key enzyme is angiotensin converting enzyme (ACE) that converts angiotensin I into the powerful vasoconstrictor, angiotensin II. Angiotensin II binds to its receptors (AT1) on smooth muscle cells of the arteriole vasculature causing vasoconstriction and elevation of blood pressure. This review focuses on the in vitro and in vivo reports of plant-derived extracts that inhibit ACE activity, block angiotensin II receptor binding and demonstrate hypotensive activity in animal or human studies. We describe 74 families of plants that exhibited significant ACE inhibitory activity and 16 plant families with potential AT1 receptor blocking activity, according to in vitro studies. From 43 plant families including some of those with in vitro bioactivity, the extracts from 73 plant species lowered blood pressure in various normotensive or hypertensive in vivo models by the oral route. Of these, 19 species from 15 families lowered human BP when administered orally. Some of the active plant extracts, isolated bioactives and BP-lowering mechanisms are discussed.

Biothermodynamic Assay of Coptis-Evodia Herb Couples

Objective. To illustrate the difference in cold/hot natural properties and therapeutic effect of coptis-evodia herb couples by using cold/hot plate differentiating technology and microcalorimetry combined with material basis analysis in vivo and in vitro. It showed that animal retention ratio in hot pad significantly decreased along with the decrease in coptis proportion in coptis-evodia herb couples. In addition, Zuojin wan markedly reduced the retention ratio of gastritis mice in the hot pad, while Fanzuojin wan displayed an opposite result. Further, Mg²⁺-ATPase, Ca²⁺-ATPase, and T-AOC activity significantly weakened in coptis-treated group in the livers of the mice. In the gastric cells from the gastritis mice, Fanzuojin wan remarkably increased calorific value for growth and metabolism, while Zuojin wan significantly reduced the calorigenic effect. It suggested that the changes in the major chemical compositions (especially alkaloids) were the material base-induced transformation between “cold” and “hot” syndromes. The material basis which affected the transformation between “cold” and “hot” syndromes might be X₂, X₃, X₄, X₈, epiberberine hydrochloride, jatrorrhizine hydrochloride, coptisine sulphate, palmatine hydrochloride, and berberine hydrochloride. The CHPD combined with microcalorimetry technology is a good method to determine the differences in the “cold” and “hot” natural properties of coptis-evodia herb couples.

Evaluation of the Effects of Some Brazilian Medicinal Plants on the Production of TNF- α and CCL2 by THP-1 Cells

Several plant species are traditionally used in Brazil to treat various inflammatory diseases. Tumor necrosis factor- (TNF-) α and chemokine (C-C motif) ligand 2 (CCL2) are key inflammatory mediators in diseases like rheumatoid arthritis and atherosclerosis, respectively; nevertheless, only a few extracts have been assayed against these targets. We herein report the effect of 19 plant extracts on TNF-α and CCL2 release by lipopolysaccharide- (LPS-) stimulated THP-1 cells, a human monocytic leukemia cell line, along with their radical scavenging activity on DPPH. The extracts of Caryocar brasiliense, Casearia sylvestris, Coccoloba cereifera, and Terminalia glabrescens inhibited TNF-α production in a concentration-dependent manner. Fractionation of these extracts potentiated the anti-TNF-α effect, which was shown to concentrate in polar fractions, mainly composed by polyphenols. Significant CCL2 inhibition was elicited by Lippia sidoides and Terminalia glabrescens extracts, whose fractionation resulted in highly active low polar fractions. All assayed extracts showed strong radical scavenging activity, but antioxidant activity did not correlate with inhibition of TNF-α or CCL2 production. Our results allowed identifying extracts with selective capacity to block cytokine production; therefore, further purification of these extracts may yield molecules that could be useful in the treatment of chronic inflammatory diseases.

Interplay between brain stem angiotensins and monocyte chemoattractant protein-1 as a novel mechanism for pressor response after ischemic stroke

Pressor response after stroke commonly leads to early death or susceptibility to stroke recurrence, and detailed mechanisms are still lacking. We assessed the hypothesis that the renin-angiotensin system contributes to pressor response after stroke by differential modulation of the pro-inflammatory chemokine monocyte chemoattractant protein-1 (MCP-1) in the rostral ventrolateral medulla (RVLM), a key brain stem site that maintains blood pressure. We also investigated the beneficial effects of a novel renin inhibitor, aliskiren, against stroke-elicited pressor response. Experiments were performed in male adult Sprague-Dawley rats. Stroke induced by middle cerebral artery occlusion elicited significant pressor response, accompanied by activation of angiotensin II (Ang II)/type I receptor (AT1R) and AT2R signaling, depression of Ang-(1-7)/MasR and Ang IV/AT4R cascade, alongside augmentation of MCP-1/C-C chemokine receptor 2 (CCR2) signaling and neuroinflammation in the RVLM. Stroke-elicited pressor response was significantly blunted by antagonism of AT1R, AT2R or MCP-1/CCR2 signaling, and eliminated by applying Ang-(1-7) or Ang IV into the RVLM. Furthermore, stroke-activated MCP-1/CCR2 signaling was enhanced by AT1R and AT2R activation, and depressed by Ang-(1-7)/MasR and Ang IV/AT4R cascade. Aliskiren inhibited stroke-elicited pressor response via downregulating MCP-1/CCR2 activity and reduced neuroinflammation in the RVLM; these effects were potentiated by Ang-(1-7) or Ang IV. We conclude that whereas Ang II/AT1R or Ang II/AT2R signaling in the brain stem enhances, Ang-(1-7)/MasR or Ang IV/AT4R antagonizes pressor response after stroke by differential modulations of MCP-1 in the RVLM. Furthermore, combined administration of aliskiren and Ang-(1-7) or Ang IV into the brain stem provides more effective amelioration of stroked-induced pressor response.

Berberine mitigates cyclophosphamide-induced hepatotoxicity by modulating antioxidant status and inflammatory cytokines

OBJECTIVES

The present study was designed to investigate the possible protective effects of berberine against cyclophosphamide (CP)-induced hepatotoxicity in rats.

METHODS

The experimental rats were treated with berberine orally at a dose of 50 mg/kg for 11 consecutive days after the administration of a single intraperitoneal dose of CP (200 mg/kg). The hepatoprotective effect of berberine was evaluated by assaying liver function markers, the pro-inflammatory cytokine tumor necrosis factor alpha (TNF-α), antioxidant defense system and gene expressions of both TNF-α and cyclooxygenase 2 (COX-2).

RESULTS

The biochemical results showed that administration of CP induced hepatic damage associated with a significant increase in the serum marker enzymes aspartate and alanine transaminases (AST, ALT) and alkaline phosphatase (ALP), and a significant increase in serum total bilirubin accompanied with a decrease in serum albumin concentration. In addition, CP-administration induced oxidative stress in the liver as evident from the increased lipid peroxidation (LPO), declined glutathione (GSH) content and glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities. Moreover, administration of CP was associated with a significant increase in serum TNF-α. Similarly, CP administration was accompanied by a significant increase in the mRNA expression of both TNF-α and COX-2 in the liver as indicated by the qPCR assay. Concomitant administration of berberine efficiently alleviated the altered biochemical parameters.

CONCLUSION

Berberine showed a marked hepatoprotective effect against CP-induced hepatotoxicity through alleviation of the elevated serum marker enzymes in addition to its antioxidant and anti-inflammatory efficacies.

Influence of nonpolar substances on the extraction efficiency of six alkaloids in Zoagumhwan investigated by ultra performance liquid chromatography and photodiode array detection

A reverse phase ultra performance liquid chromatography and photodiode array (UPLC-PDA) detection method was established for the determination of six alkaloids in Zoagumhwan (ZGW), and further for investigating the influence of nonpolar substances on the extraction efficiency of these alkaloids. The method was based on a BEH C(18) (50 mm × 2.1 mm, 1.7 μm) column and mobile phase of aqueous phosphoric acid and acetonitrile including 0.05% buffer solution under gradient elution. ZGW samples of ZGW I, II, III and IV were obtained and prepared by pre-processing the crude materials of Coptidis rhizoma and Evodiae fructus using four technologies, namely direct water decoction, removal of nonpolar substances in Evodiae fructus by supercritical fluid extraction (SFE), removal of nonpolar substances in ZGW by SFE and removal of nonpolar substances in ZGW by steam distillation. The developed and validated UPLC-PDA method was precise, accurate and sensitive enough based on the facts that the six alkaloids showed good regression (r > 0.9998), the limit of detections and quantifications for six alkaloids were less than 28.8 and 94.5 ng/mL, respectively, and the recovery was in the range of 98.56%-103.24%. The sequence of the total contents of six alkaloids in these samples was ZGW II > ZGW IV > ZGW III > ZGW I. ZGW II, in which nonpolar substances, including essential oils, were firstly removed from Evodiae fructus by SFE, had the highest content of the total alkaloids, indicating that extraction efficiency of the total alkaloids could be remarkably increased after Evodiae fructus being extracted by SFE.

HMC05, Herbal Formula, Inhibits TNF-α-Induced Inflammatory Response in Human Umbilical Vein Endothelial Cells

Vascular inflammation has been implicated in the progression of cardiovascular diseases such as atherosclerosis. In the present study, we found that HMC05, an extract from eight different herbal mixtures, dose-dependently inhibited tumor necrosis factor-α (TNF-α)-induced adhesion of monocytes to endothelial cells. Such inhibitory effect of HMC05 correlated with suppressed expression of monocyte chemoattractant protein-1, CC chemokine receptor 2, vascular cell adhesion molecule-1 and intercellular cell adhesion molecule-1. In addition, HMC05 significantly inhibited production of reactive oxygen species (ROS) and nuclear factor (NF)-κB activation by TNF-α. Those inhibitory effects of HMC05 (1–10 μg mL⁻¹) on the TNF-α-induced inflammatory event was similar to those of berberine (1–10 μM), which is a major component of HMC05 and one of herbal compounds known to have vasorelaxing and lipid-lowering activities. However, berberine significantly reduced the viability of HUVECs in a time- and concentration-dependent manner. In contrast, HMC05 (1–10 μg ml⁻¹) did not affect the cell viability for up to 48 h treatment. In conclusion, we propose that HMC05 may be a safe and potent herbal formula against vascular inflammation, and its action may be attributable to the inhibition of ROS- and NF-κB-dependent expression of adhesion molecules and chemokines.

Anti-atherogenic effect of San-Huang-Xie-Xin-Tang, a traditional Chinese medicine, in cultured human aortic smooth muscle cells

AIM OF THE STUDY

San-huang-xie-xin-tang (SHXXT) is a traditional Chinese medicine and it has been shown to have an anti-inflammatory effect. Since inflammation is one of the major mechanisms of atherosclerosis, we aimed to investigate anti-atherosclerotic effect of SHXXT in human aortic smooth muscle cells (HASMCs).

MATERIALS AND METHODS

Human aortic smooth muscle cells (HASMCs) were used in the present study, and rendered atherosclerosis by adding lipopolysaccharides. We first tested the effects of SHXXT on HASMC migration and proliferation as they present the major morphological change of atherosclerosis. We also examined whether SHXXT can influence the production of several biomarkers of inflammation and atherosclerosis including reactive oxygen species (ROS), COX-2, ERK1/2, IL-1β, IL-6, IL-8 and MCP-1.

RESULTS

Using the dimethyl-thiazol-diphenyltetrazoliumbromide (MTT) and wound repair assay, SHXXT was shown to significantly reduce HASMC proliferation and migration, respectively. From the fluorometric assay, SHXXT significantly reduced ROS production. SHXXT down regulated mRNA and protein levels for the COX-2 gene. In addition, phosphorylated ERK1/2 levels were suppressed by SHXXT suggesting HASMC division can be inhibited under pro-inflammatory condition. SHXXT significantly inhibited the production of IL-1β, IL-6, IL-8 and MCP-1 after LPS stimulation.

CONCLUSIONS

Our results indicated that SHXXT can influence several mechanisms involved in atherosclerosis, which suggests that SHXXT may have a therapeutic potential for cardiovascular disease associated with atherosclerosis.

Rhizoma Coptidis inhibits LPS-induced MCP-1/CCL2 production in murine macrophages via an AP-1 and NFkappaB-dependent pathway

Introduction. The Chinese extract Rhizoma coptidis is well known for its anti-inflammatory, antioxidative, antiviral, and antimicrobial activity. The exact mechanisms of action are not fully understood. Methods. We examined the effect of the extract and its main compound, berberine, on LPS-induced inflammatory activity in a murine macrophage cell line. RAW 264.7 cells were stimulated with LPS and incubated with either Rhizoma coptidis extract or berberine. Activation of AP-1 and NFκB was analyzed in nuclear extracts, secretion of MCP-1/CCL2 was measured in supernatants. Results. Incubation with Rhizoma coptidis and berberine strongly inhibited LPS-induced monocyte chemoattractant protein (MCP)-1 production in RAW cells. Activation of the transcription factors AP-1 and NFκB was inhibited by Rhizoma coptidis in a dose- and time-dependent fashion. Conclusions. Rhizoma coptidis extract inhibits LPS-induced MCP-1/CCL2 production in vitro via an AP-1 and NFκB-dependent pathway. Anti-inflammatory action of the extract is mediated mainly by its alkaloid compound berberine.

Angiotensin II induces C-reactive protein expression through ERK1/2 and JNK signaling in human aortic endothelial cells

BACKGROUND

Atherosclerosis is an inflammatory disease in the vessel. As an inflammatory cytokine, C-reactive protein (CRP) participates in atherogenesis. Although angiotensin II (AngII) is known to evoke inflammatory response in vascular endothelial cells (VECs), there is no direct evidence to demonstrate the proinflammatory effect of AngII on VECs through CRP. The present study focused on effect of AngII on CRP expression and the signal pathway in human aortic endothelial cells (HAECs).

METHODS AND RESULTS

mRNA and protein expression was identified by RT-PCR and Western blot, respectively. Reactive oxygen species (ROS) were observed by a fluorescence microscope. The results showed that AngII significantly increased mRNA and protein expression of CRP in HAECs in time- and concentration-dependent ways. Anti-IL-1beta and anti-IL-6 neutralizing antibodies did not affect AngII-induced CRP expression. Losartan reduced AngII-induced CRP expression in mRNA and protein levels in HAECs. Losartan and TIFA decreased AngII-stimulated ROS generation, and antioxidant NAC completely abolished AngII-induced CRP expression in HAECs. The further study indicated that losartan, NAC, PD98059, SP600125 significantly inhibited ERK1/2 and JNK phosphorylation, and PD98059, SP600125, PDTC completely antagonized AngII-induced CRP expression in HAECs.

CONCLUSIONS

The present study demonstrates that AngII has ability to induce CRP expression in HAECs through AT(1)-ROS-ERK1/2 and JNK-NF-kappaB signal pathway, which strengthens understanding of the proinflammatory and proathroscerotic actions of AngII.

Berberine inhibits NADPH oxidase mediated superoxide anion production in macrophagesThis article is one of a selection of papers published in a Special Issue on Oxidative Stress in Health and Disease

Oxidative stress and amplified redox signaling contribute to the pathogenesis of many human diseases including atherosclerosis. The superoxide-generating phagocytic NADPH oxidase is a key source of oxidative stress in the developing atheroma. The aim of the present study was to examine the effect of berberine, a plant-derived alkaloid, on NADPH oxidase-mediated superoxide anion production in macrophages. Lipopolysaccharide (LPS) treatment activated NADPH oxidase in THP-1 monocyte-derived macrophages and increased the intracellular level of superoxide anions. Preincubation of cells with berberine demonstrated a concentration-dependent (10–50 µmol/L) and time-dependent (6–24 h) inhibition of superoxide anion generation in LPS-stimulated macrophages. Cell viability tests confirmed that berberine, at concentrations sufficient for inhibiting NADPH oxidase-mediated superoxide anion generation in macrophages, did not affect cell viability. Real-time PCR analysis revealed that addition of berberine to the culture medium was able to reduce gp91phox mRNA expression in LPS-treated cells. Berberine also restored superoxide dismutase (SOD) activity, which was found to be inhibited by LPS treatment. In conclusion, results from the present study demonstrate that berberine can effectively reduce intracellular superoxide levels in LPS- stimulated macrophages. Such a restoration of cellular redox by berberine is mediated by its selective inhibition of gp91phox expression and enhancement of SOD activity. The therapeutic relevance of berberine in the prevention and management of atherosclerosis remains to be further investigated.

Protection by and anti-oxidant mechanism of berberine against rat liver fibrosis induced by multiple hepatotoxic factors

1. The aim of the present study was to investigate the effect and mechanism of berberine, an alkaloid extracted from the traditional Chinese medicine coptis, on rat liver fibrosis induced by multiple hepatotoxic factors. 2. Male Wistar rats were separated into five groups, a normal control group, a fibrotic control group and fibrotic groups treated with three different doses of berberine. The fibrotic models were established by introduction of multiple hepatotoxic factors, including CCl(4), ethanol and high cholesterol. Rats in the treatment groups were administered 50, 100 or 200 mg/kg berberine, intragastrically, daily for 4 weeks. Serum levels of alanine aminotransferase (ALT) and serum aspartate aminotransferase (AST), hepatic activity of superoxide dismutase (SOD) and hepatic malondialdehyde (MDA) and hepatic hydroxyproline (Hyp) content were determined. Liver biopsies were obtained for histological and immunohistochemical studies to detect the expressions of alpha-smooth muscle actin (SMA) and transforming growth factor (TGF)-beta1. 3. The results showed that, compared with the fibrotic control group, serum levels of ALT and AST and hepatic content of MDA and Hyp were markedly decreased, but the activity of hepatic SOD was significantly increased in berberine-treated groups in a dose-dependent manner. In addition, histopathological changes, such as steatosis, necrosis and myofibroblast proliferation, were reduced and the expression of a-SMA and TGF-b1 was significantly downregulated in the berberine-treated groups (P < 0.01). 4. These results suggest that berberine could be used to prevent experimental liver fibrosis through regulation of the anti-oxidant system and lipid peroxidation.