Bioavailability and hepatoprotection enhancement of berberine and its nanoparticles prepared by liquid antisolvent method

The study was devised to prepare berberine nanoparticles by anti-solvent precipitation method and were assessed for their hepatoprotective effect in Male Sprague-Dawley rats against carbon tetrachloride. The pharmacokinetic parameters of the prepared nanoparticles and berberine were evaluated in rabbits. Histopathological studies and blood biochemical analyses were carried out to evaluate the role of both forms of berberine in the experimental animals. Substantial improvement in the liver function test enzymes levels and liver histopathology were achieved in the animals treated with berberine nanoparticles in comparison to the unprocessed berberine whereas, pharmacokinetic parameters for nanoform of berberine were about 3.97 and 3.88 folds higher than that of the unprocessed berberine. The study revealed that the reduction of berberine particle size to nano range improved pharmacokinetic parameters in rabbits. The nano berberine provided better liver protection in experimental rats and high berberine blood concentration. Thus, better hepatoprotective and pharmacokinetics effects were observed for the nano form in comparison to unprocessed form.     

Clinical trial of berberine in acute watery diarrhoea.

Four hundred adults presenting with acute watery diarrhoea were entered into a randomised, placebo controlled, double blind clinical trial of berberine, tetracycline, and tetracycline and berberine to study the antisecretory and vibriostatic effects of berberine. Of 185 patients with cholera, those given tetracycline or tetracycline and berberine had considerably reduced volume and frequency of diarrhoeal stools, duration of diarrhoea, and volumes of required intravenous and oral rehydration fluid. Berberine did not produce an antisecretory effect. Analysis by factorial design equations, however, showed a reduction in diarrhoeal stools by one litre and a reduction in cyclic adenosine monophosphate concentrations in stools by 77% in the groups given berberine. Considerably fewer patients given tetracycline or tetracycline and berberine excreted vibrios in stools after 24 hours than those given berberine alone. Neither tetracycline nor berberine had any benefit over placebo in 215 patients with non-cholera diarrhoea.     

小檗碱对2型糖尿病ICR小鼠模型的治疗作用

目的比较小檗碱及小檗碱与添加剂对2型糖尿病ICR小鼠模型的降糖、降脂效果。方法100只三周龄雄性ICR小鼠随机分为正常组、模型组、小檗碱组、小檗碱加低剂量添加剂组、小檗碱加高剂量添加剂组及二甲双胍组,以高糖高脂加尿链佐菌素诱导小鼠2型糖尿病模型,并分别以小檗碱、小檗碱加低剂量添加剂、小檗碱加高剂量每天灌胃干预治疗6周。检测血糖、血清血脂、肾功指标的变化情况;给药前后做糖耐量胰岛素耐量实验。每周量小鼠体重,动态观察小鼠体重变化。代谢笼中测量小鼠饮食水量变化。结果模型组血糖较普食组显著上升（P〈0.01）,且维持较好;血脂指标CHO、HDL-c、LDL-c均较普食组升高（P〈0.05）;其他各检测生化指标差异不显著。小檗碱组空腹血糖较模型组总体下降趋势明显且维持较好（P〈0.01）;血脂较模型组有降低;糖耐量胰岛素耐量较模型组有改善。二甲双胍组血糖较模型组有下降趋势,血脂较模型组无显著差别。小檗碱加低剂量添加剂组较模型组血糖血脂无显著差别。小檗碱加高剂量添加剂组血糖较模型有下降趋势,血脂较模型组有下降趋势,其他各项生化指标均无差别。结论小檗碱降糖效果优于二甲双胍,小檗碱加低剂量添加剂,小檗碱加高添加剂。     

Identification of a novel and potent inhibitor of phospholipase A(2) in a medicinal plant: crystal structure at 1.93Å and Surface Plasmon Resonance analysis of phospholipase A(2) complexed with berberine

Crystal of Russell Viper venom phospholipase A(2) complexed with an isoquinoline alkaloid, berberine from a herbaceous plant Cardiospermum halicacabum, was prepared and its structure was solved by X-ray crystallography. The crystal diffracted up to 1.93? and the structure solution clearly located the position of berberine in the active site of the enzyme. Two hydrogen bonds, one direct and the other water mediated, were formed between berberine and the enzyme. Gly 30 and His 48 made these two hydrogen bonds. Additionally, the hydrophobic surface of berberine made a number of hydrophobic contacts with side chains of neighboring amino acids. Surface Plasmon Resonance studies revealed strong binding affinity between berberine and phospholipase A(2). Enzyme inhibition studies proved that berberine is a competitive inhibitor of phospholipase A(2). It was inferred that the isoquinoline alkaloid, berberine, is a potent natural inhibitor of phospholipaseA(2).     

Inhibition of CYP450 1A and 3A by berberine in crucian carp Carassius auratus gibelio

Berberine has long been considered as an antibiotic candidate in aquaculture. However, studies regarding its effects on drug-metabolizing enzymes in fish are still limited. In the present study, the effects of berberine on cytochrome P4501A (CYP1A) and CYP3A in crucian carp were investigated. Injection of different concentrations of berberine (0, 5, 25, 50, and 100 mg/kg) inhibited the CYP1A mRNA expression, thereby inhibiting further the catalytic activity of CYP1A-related ethoxyresorufin-O-deethylase (EROD). Furthermore, both CYP1A expression and EROD activity were further inhibited with increasing berberine concentrations. In addition, the CYP3A expressions at both the mRNA and the protein levels were downregulated by higher berberine concentrations. The catalytic activity of CYP3A-related erythromycin N-demethylase (ERND) was also inhibited by berberine at a dose of no less than 25 mg/kg. Moreover, at the berberine concentration exceeding 25 mg/kg, the inhibition of CYP3A expression and ERND activity increased with increasing berberine concentrations. In vitro experiments were also performed. When berberine was pre-incubated with the crucian carp liver microsomes, it competitively inhibited the corresponding EROD activity with the IC₅₀ of 11.7 μM. However, the ERND activity was slightly inhibited by berberine with the IC₅₀ of 206.4 μM. These results suggest that, in crucian carp, berberine may be a potent inhibitor to CYP1A, whereas the CYP3A inhibition needs a higher concentration of berberine.     

Kinetic difference of berberine between hippocampus and plasma in rat after intravenous administration of Coptidis rhizoma extract

In order to investigate the pharmacokinetics of berberine in Coptidis rhizoma extract in rat hippocampus and plasma, a simple and accurate high-performance liquid chromatography method was employed in this study. Berberine was determined using a Hypersil C(18) column with an isocratic mobile phase of acetonitrile-0.05 M potassium dihydrogen phosphate (containing 0.5% triethylamine, pH 3.0) and with UV detection at 236 nm. The lower limit of quantification for berberine in both hippocampus and plasma was 24 ng/ml, and the lowest concentrations of berberine determined in rat hippocampus and plasma samples were 30.7 ng/ml at 48 h and 38.5 ng/ml at 4 h, respectively. The calibration curve for berberine was linear over the concentration range 24--6000 ng/ml. At this concentration range, the overall recoveries (90.6--94.2%) for berberine were determined and the accuracy of intra- and inter-day assays from rat samples were less than 7% RSD. Following intravenous administration of C. rhizoma extract at a dose of 10.2 mg/kg containing 3 mg/kg berberine, berberine in the plasma eliminated rapidly (t(1/2 beta)=1.13 h). However, berberine in the hippocampus increased rapidly (t(1/2 alpha)=0.215 h), peaked at 3.67 h with a concentration of 272 ng/g, and had a slow elimination rate (t(1/2 beta)=12.0 h), which suggests that berberine could have a direct action on neuron and accumulate in the hippocampus. This study first showed the pharmacokinetic characteristics of berberine in rat hippocampus and the kinetic characteristics of berberine are dissimilar in the hippocampus and plasma.     

Characterization of vacuolar transport of the endogenous alkaloid berberine in Coptis japonica

Alkaloids comprise one of the largest groups of plant secondary metabolites. Many of them exhibit strong biological activities, and, in most cases, they are accumulated in the central vacuole of alkaloid-producing plants after synthesis. However, the mechanisms involved in alkaloid transport across the tonoplast are only poorly understood. In this study, we analyzed the vacuolar transport mechanism of an isoquinoline alkaloid, berberine, which is produced and accumulated in the vacuole of cultured cells of Coptis japonica. The characterization of berberine transport using intact vacuoles and a tonoplast vesicle system showed that berberine uptake was stimulated by Mg/ATP, as well as GTP, CTP, UTP, and Mg/pyrophosphate. Berberine uptake was strongly inhibited by NH4(+) and bafilomycin A1, while vanadate, which is commonly used to inhibit ATP-binding cassette transporters, had only a slight effect, which suggests the presence of a typical secondary transport mechanism. This is contrary to the situation in the plasma membrane of this plant cell, where the ATP-binding cassette transporter is involved in berberine transport. Model experiments with liposomes demonstrated that an ion-trap mechanism was hardly implicated in berberine transport. Further studies suggested that berberine was transported across the tonoplast via an H+/berberine antiporter, which has a Km value of 43.7 microM for berberine. Competition experiments using various berberine analogs, as well as other classes of alkaloids, revealed that this transporter is fairly specific, but not exclusive, for berberine.     

Binding of berberine to bovine serum albumin: spectroscopic approach

Fluorescence spectroscopy in combination with UV–vis absorption spectroscopy was employed to investigate the binding of an important traditional medicinal herb berberine to bovine serum albumin (BSA) under the physiological conditions. In the mechanism discussion, it was proved that the fluorescence quenching of BSA by berberine is a result of the formation of berberine–BSA complex. Fluorescence quenching constants were determined using the Stern–Volmer equation and Scatchard equation to provide a measure of the binding affinity between berberine and BSA. The results of thermodynamic parameters ΔG, ΔH, ΔS at different temperatures indicate that the electrostatic interactions play a major role for berberine–BSA association. Site marker competitive experiments indicated that the binding of berberine to BSA primarily took place in site II. Furthermore, the Effect of supramolecules to berberine–BSA system, and the distance r between donor (BSA) and acceptor (berberine) was obtained according to fluorescence resonance energy transfer (FRET).     

Berberine potently attenuates intestinal polyps growth in ApcMin mice and familial adenomatous polyposis patients through inhibition of Wnt signalling

As a traditional anti‐inflammatory Chinese herbal medicine, Alkaloid berberine has been recently reported to exhibit anti‐tumour effects against a wide spectrum of cancer. However, the mechanism was largely unknown. Gene chip array reveals that with berberine treatment, c‐Myc, the target gene of Wnt pathway, was down‐regulated 5.3‐folds, indicating that berberine might inhibit Wnt signalling. TOPflash analysis revealed that Wnt activity was significantly reduced after berberine treatment, and the mechanism of which might be that berberine disrupted β‐catenin transfer to nucleus through up‐regulating the expression of adenomatous polyposis coli (APC) gene and stabilized APC‐β‐catenin complex. Berberine administration in ApcMin/+ mice exhibited fewer and smaller polyps in intestine, along with reduction in cyclin D1 and c‐Myc expression. In clinical practice, oral administration of berberine also significantly reduced the familial adenomatous polyposis patients' polyp size along with the inhibition of cyclin D1 expression in polyp samples. These observations indicate that berberine inhibits colon tumour formation through inhibition of Wnt/β‐catenin signalling and berberine might be a promising drug for the prevention of colon cancer.     

Inverted binding due to a minor structural change in berberine enhances its phospholipase A2 inhibitory effect

Biotransformation of berberine by Rhizopus oryzae leads to its demethylation, producing hydroxyl derivatives, as revealed by Fourier Transform Infra Red spectroscopy, Nuclear Magnetic Resonance and Electro Spray Ionization-Mass Spectrometric analyses. Surface Plasmon Resonance and enzyme kinetic studies showed that biotransformed derivatives of berberine had a higher inhibitory potential than berberine towards phospholipase A(2). X-ray crystal structures demonstrated that biotransformed berberine binds to PLA(2) in an entirely different, inverted orientation with respect to the binding of berberine. This study brings out the significance of biotransformation in generation of better drug-lead compounds.     

Habitat‐Dependent Variations in Berberine Content of Berberis asiatica Roxb. ex. DC. in Kumaon,Western Himalaya

The variation of the berberine content in roots and stem bark of Berberis asiatica with altitude and edaphic conditions in the western Himalaya was estimated by HPLC. The comparative assessment revealed a significantly higher berberine content in roots than in stem barks. Moreover, the berberine content varied significantly with altitude and edaphic conditions both in root and stem bark samples. The populations growing at low altitude contained significantly more berberine than the ones growing at high altitude. Also the moisture and potassium (K) percentage of the soil significantly influenced the berberine content.     

Berberine via suppression of transient receptor potential vanilloid 4 channel improves vascular stiffness in mice

Berberine, as an alkaloid found in many Chinese herbs, improves vascular functions in patients with cardiovascular diseases. We determined the effects of berberine in hypertension and vascular ageing, and elucidated the underlying mechanisms. In isolated aortas, berberine dose‐dependently elicited aortic relaxation. In cultured cells, berberine induced the relaxation of vascular smooth muscle cells (VSMCs). Overexpression of transient receptor potential vanilloid 4 (TRPV4) channel by genetic approaches abolished the berberine‐induced reduction in intracellular Ca²⁺ concentration in VSMCs and attenuated berberine‐elicited vessel dilation in mice aortas. In deoxycorticosterone acetate (DOCA)‐induced hypertensive model, treatment of mice with berberine or RN‐1734, a pharmacological inhibitor of TRPV4, significantly decreased systemic blood pressure (BP) in control mice or mice infected with an adenovirus vector. However, berberine‐induced effects of lowering BP were reversed by overexpressing TRPV4 in mice by infecting with adenovirus. Furthermore, long‐term administration of berberine decreased mean BP and pulse BP, increased artery response to vasodilator and reduced vascular collagen content in aged mice deficient in apolipoprotein E (Apoe‐KO), but not in Apoe‐KO old mice with lentivirus‐mediated overexpression of TRPV4 channel. In conclusion, berberine induces direct vasorelaxation to lower BP and reduces vascular stiffness in aged mice through suppression of TRPV4.     

Energy-requiring uptake of protoberberine alkaloids by cultured cells ofThalictrum flavum

Cultured cells ofThalictrum flavum take up berberine exogenously added to medium against the concentration gradient. This uptake was temperature-dependent and sensitive to plasma membrane-bound ATPase inhibitors such as sodium orthovanadate and diethylstilbestrol, indicating that the process is mediated by an energy-requiring system. The time-course of pH-shift during berberine uptake suggests the participation of a berberine-proton antiport system in the berberine uptake by the cultured cells. In addition, the existence of a specific transport system was suggested by the competitive inhibition of berberine uptake by berberine analogues, coptisine and jatrorrhizine.     

Improvement of anti-inflammatory and anti-angiogenic activity of berberine by novel rapid dissolving nanoemulsifying technique

Berberine, an isoquinoline alkaloid, has wide biological and pharmacological actions. Despite the promising pharmacological effects and safety of berberine, poor oral absorption due to its extremely low aqueous solubility results in poor oral systemic bioavailability. This limits its clinical usage. This study describes the development and characterization of self-nanoemulsifying drug delivery system (SNEDDS) of berberine in liquid as well as solid form with improved solubility, dissolution and in vivo therapeutic efficacy. The SNEDDS of berberine were prepared using Acrysol K-150, Capmul MCM and polyethylene glycol 400. The formulations were characterized for various in vitro physicochemical characteristics. In vivo efficacy was evaluated in acetic acid induced inflammatory bowel model in rats. Anti-angiogenic activity of the developed SNEDDS of berberine was studied using chick chorioallantoic membrane assay. SNEDDS of berberine rapidly formed nanoemulsions with globule size of 17–45 nm. The in vitro rate and extent of release of berberine from SNEDDS was significantly higher than berberine alone. Chick chorioallantoic membrane assay revealed potent anti-angiogenic activity of SNEDDS of berberine. These studies demonstrate that the SNEDDS of berberine is a promising strategy for improving its therapeutic efficacy and have potential application in the treatment of chronic inflammatory conditions and cancer.     

Specific differences in tolerance to exogenous berberine among plant cell cultures

The tolerance of plant cells to exogenously administered berberine, an antimicrobial isoquinoline alkaloid, was studied using berberine-producing and nonproducing cell suspension cultures. Both Coptis japonica and Thalictrum flavum cells, which have an intrinsic ability to synthesize berberine, took up exogenous berberine from the culture medium by an energy-requiring active transport to accumulate it exclusively in vacuoles. By contrast, T. minus cells, which excrete indigenous berberine mostly into the medium, did not take up exogenously supplied berberine, indicating that the alkaloid transport in this species is unidirectional. No inhibition of cell growth by exogenous berberine was observed in the three berberine-producing cell cultures. On the other hand, a small amount of exogenous berberine strongly inhibited cell growth in the berberine-free cultures of Datura innoxia, Catharanthus roseus, and Paeonia albiflora. The berberine taken up actively by Datura cells could not be transported into vacuoles but was dispersed in the cytoplasm, causing a severe inhibition of cell growth.     

Lipid-lowering effect of berberine in human subjects and rats

Due to serious adverse effects and the limited effectiveness of currently available pharmacological therapies for obesity, many research efforts have focused on the development of drugs from natural products. Our previous studies demonstrated that berberine, an alkaloid originally isolated from traditional Chinese herbs, prevented fat accumulation in vitro and in vivo. In this pilot study, obese human subjects (Caucasian) were given 500 mg berberine orally three times a day for twelve weeks. The efficacy and safety of berberine treatment was determined by measurements of body weight, comprehensive metabolic panel, blood lipid and hormone levels, expression levels of inflammatory factors, complete blood count, and electrocardiograph. A Sprague-Dawley rat experiment was also performed to identify the anti-obesity effects of berberine treatment. The results demonstrate that berberine treatment produced a mild weight loss (average 5 lb/subject) in obese human subjects. But more interestingly, the treatment significantly reduced blood lipid levels (23% decrease of triglyceride and 12.2% decrease of cholesterol levels) in human subjects. The lipid-lowering effect of berberine treatment has also been replicated in the rat experiment (34.7% decrease of triglyceride and 9% decrease of cholesterol level). Cortisol, calcitriol, ACTH, TSH, FT4, and SHBG levels were not significantly changed following 12 weeks of berberine treatment. However, there was interestingly, an increase in calcitriol levels seen in all human subjects following berberine treatment (mean 59.5% increase, p=0.11). Blood inflammatory factors (CRP, IL-6, TNFα, COX-2) and erythrocyte sedimentation rate (ESR) were not significantly affected by treatment with berberine. Tests of hematological, cardiovascular, liver, and kidney function following berberine treatment showed no detrimental side effects to this natural compound. Collectively, this study demonstrates that berberine is a potent lipid-lowering compound with a moderate weight loss effect, and may have a possible potential role in osteoporosis treatment/prevention.     

The combination of berberine and irradiation enhances anti‐cancer effects via activation of p38 MAPK pathway and ROS generation in human hepatoma cells

Berberine, an isoquinoline plant alkaloid, has been known to generate a wide variety of biochemical and pharmacological effects. In order to elucidate the molecular mechanism for the berberine‐induced enhancement of radio‐sensitization, the human hepatoma HepG2 cells were treated with berberine combined with irradiation. The anti‐tumor effect of gamma radiation was found to be significantly enhanced by berberine. The evidences of apoptosis, such as apoptotic DNA fragmentation and annexin V staining, were observed in the cells treated with the combination of berberine and irradiation. Additionally, the levels of reactive oxygen species (ROS) and nitric oxide (NO) were apparently elevated in the combination system. The activations of p38, Bax, and caspase‐3 were also detected in the irradiated cells pretreated with berberine. The productions of ROS and annexin V staining in the cells treated with the combination of berberine and irradiation were significantly inhibited by the specific inhibitor of p38 MAPK, SB203580. The cell death induced by berberine alone or the combination of berberine and irradiation was suppressed by the anti‐oxidant, N‐acetyl cysteine (NAC). Taken together, the present results clearly indicate that the combination of berberine and gamma‐radiation enhance the anti‐cancer effects through the p38 MAPK pathway and ROS generation. J. Cell. Biochem. 107: 955–964, 2009. © 2009 Wiley‐Liss, Inc.     

Berberine and aspirin prevent traumatic heterotopic ossification by inhibition of BMP signalling pathway and osteogenic differentiation

Heterotopic ossification (HO) is a pathological process that often occurs in soft tissues following severe trauma. There is no effective therapy for HO. The BMP signalling pathway plays an essential role in the pathogenesis of HO. Our previous study showed that AMPK negatively regulates the BMP signalling pathway and osteogenic differentiation. The present study aims to study the effect of two AMPK activators berberine and aspirin on osteogenic differentiation and HO induced by traumatic injury. The effects of two AMPK activators, berberine and aspirin, on BMP signalling and osteogenic differentiation were measured by western blot, ALP and Alizarin red S staining in C3H10T1/2 cells. A mouse model with Achilles tenotomy was employed to assess the effects of berberine and aspirin on HO using μCT and histological analysis. First, our study showed that berberine and aspirin inhibited phosphorylation of Smad1/5 induced by BMP6 and the inhibition was attributed to the down-regulation of ALK2 expression. Second, the combination of berberine and aspirin yielded more potent effects on BMP signalling. Third, we further found that there was an additive effect of berberine and aspirin combination on osteogenic differentiation. Finally, we found that berberine and aspirin blocked trauma-induced ectopic bone formation in mice, which may be through suppression of phosphorylation of Smad1/5 in injured tissues. Collectively, these findings indicate that berberine and aspirin inhibit osteogenic differentiation in C3H10T1/2 cells and traumatic HO in mice, possibly through the down-regulation of the BMP signalling pathway. Our study sheds a light on prevention and treatment of traumatic HO using AMPK pharmacological activators berberine and aspirin.     

Uptake of and Resistance to the Antibiotic Berberine by Individual Dormant,Germinating and Outgrowing Bacillus Spores as Monitored by Laser Tweezers Raman Spectroscopy

Berberine, an alkaloid originally extracted from the plant Coptis chinensis and other herb plants, has been used as a pharmacological substance for many years. The therapeutic effect of berberine has been attributed to its interaction with nucleic acids and blocking cell division. However, levels of berberine entering individual microbial cells minimal for growth inhibition and its effects on bacterial spores have not been determined. In this work the kinetics and levels of berberine accumulation by individual dormant and germinated spores were measured by laser tweezers Raman spectroscopy and differential interference and fluorescence microscopy, and effects of berberine on spore germination and outgrowth and spore and growing cell viability were determined. The major conclusions from this work are that: (1) colony formation from B. subtilis spores was blocked ~ 99% by 25 μg/mL berberine plus 20 μg/mL INF55 (a multidrug resistance pump inhibitor); (2) 200 μg/mL berberine had no effect on B. subtilis spore germination with L-valine, but spore outgrowth was completely blocked; (3) berberine levels accumulated in single spores germinating with ≥ 25 μg/mL berberine were > 10 mg/mL; (4) fluorescence microscopy showed that germinated spores accumulated high-levels of berberine primarily in the spore core, while dormant spores accumulated very low berberine levels primarily in spore coats; and (5) during germination, uptake of berberine began at the time of commitment (T₁) and reached a maximum after the completion of CaDPA release (T_release) and spore cortex lysis (T_lysis).     

Enhancement of Sodium Caprate on Intestine Absorption and Antidiabetic Action of Berberine

Berberine, a plant alkaloid used in traditional Chinese medicine, has a wide spectrum of pharmacological actions, but the poor bioavailability limits its clinical use. The present aim was to observe the effects of sodium caprate on the intestinal absorption and antidiabetic action of berberine. The in situ, in vitro, and in vivo models were used to observe the effect of sodium caprate on the intestinal absorption of berberine. Intestinal mucosa morphology was measured to evaluate the toxic effect of sodium caprate. Diabetic model was used to evaluate antidiabetic effect of berberine coadministrated with sodium caprate. The results showed that the absorption of berberine in the small intestine was poor and that sodium caprate could significantly improve the poor absorption of berberine in the small intestine. Sodium caprate stimulated mucosal-to-serosal transport of berberine; the enhancement ratios were 2.08, 1.49, and 3.49 in the duodenum, jejunum, and ileum, respectively. After coadministration, the area under the plasma concentration–time curve of berberine was increased 28% than that in the absence of sodium caprate. Furthermore, both berberine and coadministration with sodium caprate orally could significantly decrease fasting blood glucose and improve glucose tolerance in diabetic rats (P?P?相似文献