The protective effect of coptisine on experimental atherosclerosis ApoE-/- mice is mediated by MAPK/NF-κB-dependent pathway.

Coptisine is one of main bioactive compounds extracted from the traditional Chinese herbal medicine Rhizoma Coptidis. It is reported that coptisine can attenuate obesity-related inflammation and oxidant damage in Syrian golden hamsters. Therefore，coptisine may exhibit beneficial effects for the treatment of atherosclerosis (AS) due to its hypolipidemic and anti-inflammation activities. The present study investigated the anti-atherosclerotic and anti-inflammatory properties of coptisine using apoE-/- mice as AS model. The atherosclerotic plaque area of aorta, serum lipid profile and the expression of inflammatory cytokines were determined. After coptisine treatment, the serum level of TC, TG and LDL-C decreased; the serum level of IL-6, IL-1ß and TNF-α were decreased; the mRNA levels of NF-κBp65, VCAM-1, ICAM-1, IL-6 and IL-1ß in both aorta and liver were down-regulated; the p-p38 and p-JNK1/2 protein expression level were decreased. Coptisine decreased atherosclerotic plaque area significantly through both anti-inflammation and lipid lowering effect. The anti-inflammatory effect of coptisine is achieved through inhibiting activation of MAPK signaling pathways and NF-κB nuclear translocation. Therefore，the combined anti-inflammation and lipid lowering effect of coptisine attributed the decreased atherosclerotic plaque area in coptisine treated apoE-/- mice. The results of this study will afford a novel application for coptisine in the treatment of atherosclerosis and other chronic inflammatory disease.

Comparative effect of berberine and its derivative 8-cetylberberine on attenuating atherosclerosis in ApoE-/- mice.

Berberine (BBR), one of the main bioactive compounds in Rhizoma coptidis, has multiple pharmacological activities. It has been reported that 8-cetylberberine (8-BBR-C16) has increased anti-microbial property in vivo and a higher bioavailability in hamsters. Therefore, in the present study, we used apolipoprotein E-deficient mice (ApoE-/-) as an atherosclerosis model to investigate the anti-atherosclerosis effects of 8-BBR-C16. After 12weeks of treatment, the atherosclerotic plaque area of the aorta, serum lipid profile, the plasma redox state and the expression of inflammatory cytokines in ApoE-/- mice were determined. Both BBR and 8-BBR-C16 significantly decreased the atherosclerotic plaque area by suppressing inflammatory and oxidative markers in ApoE-/- mice. Treatment with BBR or 8-BBR-C16, decreased serum levels of IL-1ß and TNF-α as well as mRNA levels of NF-κBp65, i-NOS, ICAM-1, IL-6 in the aorta. In addition, the expression of NF-κB p65 protein decreased in the nucleus, whereas IκBα levels increased in the cytosol. The anti-inflammatory and anti-oxidative effect of BBR and 8-BBR-C16 attributed to inhibition of the translocation of NF-κB to the nucleus. Since the dosage of BBR used was 10 fold higher than that of 8-cetylberberine, we conclude that 8-BBR-C16 is more efficient in treating atherosclerosis in ApoE-/- mice.

Rhizoma Coptidis alkaloids alleviate hyperlipidemia in B6 mice by modulating gut microbiota and bile acid pathways.

It is hypothesized that Rhizoma Coptidis (RC) alkaloids exert their hypolipidemic effects primarily by targeting the gastrointestinal tract and liver. Thus, this study was conducted to evaluate the antihyperlipidemic mechanisms of RC alkaloids (at a daily dose of 140mg/kg for 35days) in high-fat and high-cholesterol induced hyperlipidemic B6 mice. After treatment, serum lipid parameters were determined, the expression of lipid metabolism related genes and pathways such as the sterol regulatory element binding proteins (SREBPs) and bile acid signaling in mice were also investigated. Meanwhile, Illumina sequencing was used to investigate the differences in gut microbiota of B6 mice. The results indicated that RC alkaloids reduced the body weight gain and serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), total bile acids (TBA) and lipopolysaccharide of B6 mice. Liver fat deposition and epididymal adipose cell size were also deceased in therapy group. RC alkaloids feeding significantly promoted the abundance of Sporobacter termitidis, Alcaligenes faecalis, Akkermansia muciniphila in the gut of mice, whereas, the abundance of Escherichia coli, Desulfovibrio C21_c20, Parabacteroides distasonis was suppressed. The observed antihyperlipidemic effects of RC alkaloids can also be attributed to their action as agonists of FXR and TGR5, activators for SREBP2, LDLR, UCP2 and CYP7A1, inhibitors of HMGCR, TXNIP, TLR4 and JNK. Therefore, this study expands current knowledge on hypolipidemic mechanisms of RC alkaloids and presents new evidence supporting a key role for RC alkaloids as regulators of lipid homeostasis by modulation gut microbiota and hepatic lipid metabolism.

Antihyperglycemia and Antihyperlipidemia Effect of Protoberberine Alkaloids From Rhizoma Coptidis in HepG2 Cell and Diabetic KK-Ay Mice.

Preclinical Research Rhizoma Coptidis (RC), the root of Coptis chinensis Franch, a species in the genus Coptis (family Ranunculaceae), has been commonly prescribed for the treatment of diabetes in Chinese traditional herbal medicine applications. The present study is focused on the assessment of the antihyperglycemia and antidiabetic hyperlipidemia effect of five protoberberine alkaloids, berberine (BBR), coptisine (COP), palmatine (PAL), epiberberine (EPI), and jatrorrhizine (JAT), separated from R. Coptidis in hepatocellular carcinoma HepG2 cells and diabetic KK-Ay mice. Protoberberine alkaloids are effective in modulating hyperglycemia and hyperlipidemia. After adding BBR and COP to culture medium, glucose consumption of HepG2 cells was increased. In KK-Ay mice assays, suppressed fasting blood glucose level and ameliorated glucose tolerance were observed after BBR/COP administration. After treated with berberine and coptisine, in the same dose of 5 µg/mL, the glucose consumption of HepG2 cells were promoted and, respectively, reached 96.1% and 17.6%. Body weight, food consumption, water intake, and urinary output of KK-Ay mice were reduced after treated with EPI. Serum total cholesterol and triglyceride of mice were decreased after treated with palmatine and jatrorrhizine. Serum high-density lipoprotein cholesterol of mice was increased after palmatine, jatrorrhizine, and berberine administrated. Moreover, hepatomegaly was attenuated in JTR-treated mice. Suggested that these protoberberine alkaloids from R. Coptidis have potential curative effect for diabetes. Drug Dev Res 77 : 163-170, 2016. © 2016 Wiley Periodicals, Inc.

Hypolipidemic Effects of Alkaloids from Rhizoma Coptidis in Diet-Induced Hyperlipidemic Hamsters.

This study was conducted to evaluate the antihyperlipidemic activity of five major alkaloids in Rhizoma Coptidis using high-fat- and high-cholesterol-induced hyperlipidemic hamsters. Hyperlipidemic hamsters were treated with coptisine, berberine, jatrorrhizine, palmatine, epiberberine, and total Rhizoma Coptidis alkaloids with a dose of 46.7 mg/kg × day for 140 days. Serum total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and total bile acids were examined after alkaloid treatment. The results showed that all therapy agents prevented body weight gain, reduced the serum total cholesterol, and increased the high-density lipoprotein cholesterol of hamsters. Berberine, jatrorrhizine, and total Rhizoma Coptidis alkaloids decreased the triglyceride level in hyperlipidemic hamsters, while coptisine, jatrorrhizine, palmatine, and total Rhizoma Coptidis alkaloids significantly suppressed the elevation of the low-density lipoprotein cholesterol level. The fecal excretion of bile acids was significantly elevated by berberine, coptisine, jatrorrhizine, palmatine, total Rhizoma Coptidis alkaloids, and orlistat. Notably, total Rhizoma Coptidis alkaloids possess a much stronger lipid-lowering effect than the pure Rhizoma Coptidis alkaloids. Quantitative reverse transcription-polymerase chain reaction analyses revealed that Rhizoma Coptidis alkaloids could retard the synthesis of cholesterol by downregulating the mRNA expression of 3-hydroxy-3-methyl glutaryl coenzyme A reductase and accelerate the clearance of lipids by upregulating the low-density lipoprotein receptor, cholesterol 7α-hydroxylase, and uncoupling protein-2 expression. These findings highlight the critical role of Rhizoma Coptidis alkaloids in hyperlipidemia treatment. Thus, they need to be considered in future therapeutic approaches.

Coptisine attenuates obesity-related inflammation through LPS/TLR-4-mediated signaling pathway in Syrian golden hamsters.

It is known that obesity resulted from consumption of diets high in fat and calories and associated with a chronic low-grade inflammation. Because the fat, sterol and bile acid metabolism of male Syrian golden hamster are more similar to that of human, in the present study, high fat and high cholesterol (HFHC) induced obese hamsters were used to evaluate the anti-inflammation and hypolipidemic role of coptisine. The results showed that body weight, plasma lipid levels of total cholesterol (TC), triglyceride (TG), low density lipoprotein-cholesterol (LDL-c), very low density lipoprotein-cholesterol (VLDL-c), ApoB and pro-inflammatory cytokines including TNF-α, IL-6 and lipopolysaccharide (LPS) were significantly altered in hamsters fed with HFHC diet. A strong correlation was observed between the LPS level in serum and the level of LBP and pro-inflammatory cytokines. Coptisine from the concentrations of 60 to 700 mg/L dose-dependently inhibited Enterobacter cloacae growth, which can easily induce obesity and insulin resistance. The results of endotoxin neutralization assay suggest that coptisine is capable of reducing the LPS content under inflammation status. Real time RT-PCR analyses revealed that coptisine suppressed TLR-4 in visceral fat of hamsters and decreased CD14 expression in livers of hamsters. These encouraging findings make the development of coptisine a good candidate for preventing obesity-related diseases through the LPS/TLR-4-mediated signaling pathway.

The safety and anti-hypercholesterolemic effect of coptisine in Syrian golden hamsters.

Current work was conducted to evaluate the cholesterol-lowering effect of coptisine extracted from Rhizoma coptidis in Syrian golden hamsters. The safety results indicated that coptisine was a safe and low-toxic compound. Coptisine showed a beneficial effect in the abnormal serum lipid levels induced by a high-fat and high-cholesterol diet (HFHC): at a concentration of 70.05 mg/kg, coptisine significantly led to a decrease in total cholesterol, triglycerides, and low-density lipoprotein cholesterol (LDL-c) levels by 26.70, 15.38, and 22.22 %, respectively, and high-density lipoprotein cholesterol (HDL-c) was increased by 41.74 % in serum of hamsters (p < 0.01). In addition, total bile acid (TBA) levels in feces of hamsters were elevated after coptisine administration. Further investigation has suggested that the mRNA and protein expression of 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGCR) in the liver of hamsters was down-regulated by high-dosage coptisine treatment (p < 0.05); mRNA and protein expression of low-density lipoprotein receptor (LDLR) and cholesterol 7α-hydroxylase (CYP7A1) were dramatically up-regulated by coptisine administration. The apical sodium-dependent bile salt transporter expression was down-regulated in the coptisine-treated animals, but showed no significant differences from the HFHC groups. Taken together, our results demonstrate that a high dosage of coptisine could inhibit cholesterol synthesis via suppressing the HMGCR expression and promoting the use and excretion of cholesterol via up-regulating LDLR and CYP7A1 expression. These findings suggest a critical role for coptisine in anti- hypercholesterolemia, and thus it needs to be considered as a potential natural cholesterol lowering agent.