Berberine analogue IMB-Y53 improves glucose-lowering efficacy by averting cellular efflux especially P-glycoprotein efflux

Borneol promotes berberine-induced cardioprotection in a rat model of myocardial ischemia/reperfusion injury via inhibiting P-glycoprotein expression

Berberine is reported to protect the heart against ischemia/reperfusion (I/R) injury, although efficacy is limited by low bioavailability. This study aims to determine whether borneol, a classic guiding drug, can enhance the cardioprotection induced by berberine and to clarify the underlying mechanisms involving P-glycoprotein (P-gp) in the heart. Adult male Sprague Dawley rats were gavaged with berberine (200 mg/kg) with or without borneol (100 mg/kg) for 7 consecutive days. A rat model of myocardial I/R injury was established by 30 min left coronary artery occlusion followed with 120 min reperfusion. The arrhythmia score, cardiac enzyme content, and myocardial infarct size were determined following reperfusion. Heart tissues were collected for Western blot and immunofluorescence analyses to measure the protein expression levels of Bcl-2, Bax, and P-gp. The results showed that administration of berberine protected the heart against I/R injury, as demonstrated by lower arrhythmia scores, serum cTnI contents, myocardial infarct size, and cardiomyocytes apoptosis. Moreover, borneol substantially enhanced the cardioprotective effects of berberine. Western blot and immunofluorescence analyses showed that both berberine and I/R injury did not alter P-gp expression in heart. In contrast, borneol combined with berberine significantly reduced P-gp levels by 43.4% (P = 0.0240). Interestingly, treatment with borneol alone decreased P-gp levels, but did not protect against myocardial I/R injury. These findings suggest that borneol, as an adjuvant drug, improved the cardioprotective effects of berberine by inhibiting P-gp expression in heart. Borneol combined with berberine administration provides a new strategy to protect the heart against I/R injury.

Research progress on pharmacological effects and bioavailability of berberine

Berberine (BBR), a benzylisoquinoline alkaloid obtained from natural medicines such as coptidis rhizoma, has a wide range of pharmacological activities such as protecting the nervous system, protecting the cardiovascular system, anti-inflammatory, antidiabetic, antihyperlipidemic, antitumor, antibacterial, and antidiarrheal. However, factors such as poor solubility, low permeability, P-glycoprotein (P-gp) efflux, and hepatic-intestinal metabolism result in BBR having a low bioavailability (< 1%), which restricts its application in clinical settings. Therefore, improving its bioavailability is a prerequisite for its clinical applications. This review summarizes the various pharmacological effects of BBR and analyzes the main reasons for its poor bioavailability. It introduces methods to improve the bioavailability of BBR through the use of absorption enhancers and P-gp inhibitors, structural modification of BBR, and preparation of BBR salts and cocrystals as well as the development of new formulations and focuses on the bioavailability study of the new formulations of BBR. The research of BBR was also prospected in order to provide reference for the further research of BBR.

Berberine: Pharmacological Features in Health, Disease and Aging

BACKGROUND

Berberine is the main active compound of different herbs and is defined as an isoquinoline quaternary botanical alkaloid found in barks and roots of numerous plants. It exhibits a wide range of pharmacological effects, such as anti-obesity and antidiabetic effects. Berberine has antibacterial activity against a variety of microbiota, including many bacterial species, protozoa, plasmodia, fungi, and trypanosomes.

OBJECTIVE

This review describes the role of berberine and its metabolic effects. It also discusses how it plays a role in glucose metabolism, fat metabolism, weight loss, how it modulates the gut microbiota, and what are its antimicrobial properties along with its potential side effects with maximal tolerable dosage.

METHODS

Representative studies were considered and analyzed from different scientific databases, including PubMed and Web of Science, for the years 1982-2022.

RESULTS

Literature analysis shows that berberine affects many biochemical and pharmacological pathways that theoretically yield a positive effect on health and disease. Berberine exhibits neuroprotective properties in various neurodegenerative and neuropsychological ailments. Despite its low bioavailability after oral administration, berberine is a promising tool for several disorders. A possible hypothesis would be the modulation of the gut microbiome. While the evidence concerning the aging process in humans is more limited, preliminary studies have shown positive effects in several models.

CONCLUSION

Berberine could serve as a potential candidate for the treatment of several diseases. Previous literature has provided a basis for scientists to establish clinical trials in humans. However, for obesity, the evidence appears to be sufficient for hands-on use.

Evaluation of Intestinal Drug Absorption and Interaction Using Quadruple Single-Pass Intestinal Perfusion Coupled with Mass Spectrometry Imaging

Visualization and characterization of the intestinal membrane transporter-mediated drug absorption and interaction are challenging due to the complex physical and chemical environment. In this work, an integrated strategy was developed for in situ visualization and assessment of the drug absorption and interaction in rat intestines using quadruple single-pass intestinal perfusion (Q-SPIP) technique coupled with matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI MSI). Compared with the traditional SPIP only available for perfusion of one single intestinal segment, the Q-SPIP model can simultaneously perfuse four individual segments of each rat intestine (duodenum, jejunum, ileum, and colon), enabling to obtain rich data from one rat. Subsequently, the drug distribution and absorption in rat intestinal tissue were accurately visualized by using an optimized MALDI MSI approach. The utility and versatility of this strategy were demonstrated via the examination of P-glycoprotein (P-gp)-mediated intestinal absorption of berberine (BBR) and its combination with natural products possessing inhibitory potency against P-gp. The change in the spatial distribution of BBR was resolved, and MALDI results showed that the signal intensity of BBR in defined regions was enhanced following coperfusion with P-gp inhibitors. However, enhanced absorption of BBR after coperfusion with the P-gp inhibitor was not observed in the ulcerative colitis rat model, which may be due to the damage to the intestinal barrier. This study exemplifies the availability and utility of Q-SPIP coupled with MALDI MSI in the examination of transporter-mediated intestinal drug absorption and interaction for fundamental inquiries into the preclinical prediction of oral absorption and drug interaction potential.

Berberine inhibits carcinogenesis through antagonizing the ATX-LPA-LPAR2-p38-leptin axis in a mouse hepatoma model

Chemoprevention of hepatocellular carcinoma (HCC) is highly desirable in clinic. Berberine (BBR) is reported to play potential roles in cancer treatment and prevention. We studied the chemopreventive effect of BBR on hepatocellular carcinogenesis in an inflammation-driven mouse model, as it was enriched in liver after oral administration. Oral BBR significantly decreased the number and volume of visible nodular tumors, and prolonged the median overall survival by 9 and 8 weeks in the diethylnitrosamine (DEN)-injected male and female mice respectively. The nodular tumors were induced through activation of the lysophosphatidic acid (LPA) pathway in liver. LPA stimulated the abnormal leptin transcription through interacting with LPA receptor-2 (LPAR2) followed by p38 activation, and BBR inhibited carcinogenesis by suppressing the bioactivity of LPA. Specifically, BBR significantly reduced the expression of the LPA synthetase autotaxin (ATX) and LPAR2 in the nodular tumors of DEN-injected mice. Subsequently, BBR repressed the abnormal transcription of leptin stimulated by LPA-induced phosphorylation of p38 in hepatoma cells. In fact, BBR reduced the abnormal expression of leptin in livers of DEN-injected male mice throughout the course of an 8-month experiment. BBR might be a preventive agent for HCC, working at least partially through antagonizing the ATX-LPA-LPAR2-p38-leptin axis in liver.

Berberine: A Review of its Pharmacokinetics Properties and Therapeutic Potentials in Diverse Vascular Diseases

Traditional Chinese medicine plays a significant role in the treatment of various diseases and has attracted increasing attention for clinical applications. Vascular diseases affecting vasculature in the heart, cerebrovascular disease, atherosclerosis, and diabetic complications have compromised quality of life for affected individuals and increase the burden on health care services. Berberine, a naturally occurring isoquinoline alkaloid form Rhizoma coptidis, is widely used in China as a folk medicine for its antibacterial and anti-inflammatory properties. Promisingly, an increasing number of studies have identified several cellular and molecular targets for berberine, indicating its potential as an alternative therapeutic strategy for vascular diseases, as well as providing novel evidence that supports the therapeutic potential of berberine to combat vascular diseases. The purpose of this review is to comprehensively and systematically describe the evidence for berberine as a therapeutic agent in vascular diseases, including its pharmacological effects, molecular mechanisms, and pharmacokinetics. According to data published so far, berberine shows remarkable anti-inflammatory, antioxidant, antiapoptotic, and antiautophagic activity via the regulation of multiple signaling pathways, including AMP-activated protein kinase (AMPK), nuclear factor κB (NF-κB), mitogen-activated protein kinase silent information regulator 1 (SIRT-1), hypoxia-inducible factor 1α (HIF-1α), vascular endothelial growth factor phosphoinositide 3-kinase (PI3K), protein kinase B (Akt), janus kinase 2 (JAK-2), Ca²⁺ channels, and endoplasmic reticulum stress. Moreover, we discuss the existing limitations of berberine in the treatment of vascular diseases, and give corresponding measures. In addition, we propose some research perspectives and challenges, and provide a solid evidence base from which further studies can excavate novel effective drugs from Chinese medicine monomers.

Green-synthetized selenium nanoparticles using berberine as a promising anticancer agent

OBJECTIVE

The chemo-preventative and therapeutic properties of selenium nanoparticles (SeNPs) have been documented over recent decades and suggest the potential uses of SeNPs in medicine. Biogenic SeNPs have higher biocompatibility and stability than chemically synthesized nanoparticles, which enhances their medical applications, especially in the field of cancer therapy. This study evaluated the potential of green-synthetized SeNPs by using berberine (Ber) as an antitumor agent and elucidated the mechanism by which these molecules combat Ehrlich solid tumors (ESTs).

METHODS

SeNPs containing Ber (SeNPs-Ber) were synthesized using Ber and Na₂SeO₃ and characterized with Fourier transform infrared spectroscopy. Sixty male Swiss albino mice were then acclimatized for one week, injected with Ehrlich ascites tumor cells, and divided into four groups: EST, EST + cisplatin (5 mg/kg), EST + Ber (20 mg/kg), and EST + SeNPs-Ber (0.5 mg/kg). At the end of a 16-day observation period, 12 mice from each group were euthanized to analyze differences in the body weight, tumor size, gene expression, and oxidative stress markers in the four groups. Three mice from each group were kept alive to compare the survival rates.

RESULTS

Treatment with SeNPs-Ber significantly improved the survival rate and decreased the body weight and tumor size, compared to the EST group. SeNPs-Ber reduced oxidative stress in tumor tissue, as indicated by a decrease in the lipid peroxidation and nitric oxide levels and an increase in the glutathione levels. Moreover, SeNPs-Ber activated an apoptotic cascade in the tumor cells by downregulating the B-cell lymphoma 2 (Bcl-2) expression rate and upregulating the Bcl-2-associated X protein and caspase-3 expression rates. SeNPs-Ber also considerably improved the histopathological alterations in the developed tumor tissue, compared to the EST group.

CONCLUSION

Our study provides a new insight into the potential role of green-synthesized SeNPs by using Ber as a promising anticancer agent, these molecules could be used alone or as supplementary medication during chemotherapy.

Berberine on the Prevention and Management of Cardiometabolic Disease: Clinical Applications and Mechanisms of Action

Berberine is an alkaloid from several medicinal plants originally used to treat diarrhea and dysentery as a traditional Chinese herbal medicine. In recent years, berberine has been discovered to exhibit a wide spectrum of biological activities in the treatment of diverse diseases ranging from cancer and neurological dysfunctions to metabolic disorders and heart diseases. This review article summarizes the clinical practice and laboratory exploration of berberine for the treatment of cardiometabolic and heart diseases, with a focus on the novel insights and recent advances of the underlying mechanisms recognized in the past decade. Berberine was found to display pleiotropic therapeutic effects against dyslipidemia, hyperglycemia, hypertension, arrhythmia, and heart failure. The mechanisms of berberine for the treatment of cardiometabolic disease involve combating inflammation and oxidative stress such as inhibiting proprotein convertase subtilisin/kexin 9 (PCSK9) activation, regulating electrical signals and ionic channels such as targeting human ether-a-go-go related gene (hERG) currents, promoting energy metabolism such as activating adenosine monophosphate-activated protein kinase (AMPK) signaling pathway, modifying gut microbiota to promote transforming of berberine into its intestine-absorbable form, and interacting with non-coding RNAs via targeting multiple signaling pathways such as AMPK, mechanistic target of rapamycin (mTOR), etc. Collectively, berberine appears to be safe and well-tolerated in clinical practice, especially for those who are intolerant to statins. Knowledge from this field may pave the way for future development of more effective pharmaceutical approaches for managing cardiometabolic risk factors and preventing heart diseases.

Potential of natural products in osteosarcoma treatment: Focus on molecular mechanisms

Osteosarcoma is the most frequent type of bone cancer found in children and adolescents, and commonly arises in the metaphyseal region of tubular long bones. Standard therapeutic approaches, such as surgery, chemotherapy, and radiation therapy, are used in the management of osteosarcoma. In recent years, the mortality rate of osteosarcoma has decreased due to advances in treatment methods. Today, the scientific community is investigating the use of different naturally derived active principles against various types of cancer. Natural bioactive compounds can function against cancer cells in two ways. Firstly they can act as classical cytotoxic compounds by non-specifically affecting macromolecules, such as DNA, enzymes, and microtubules, which are also expressed in normal proliferating cells, but to a greater extent by cancer cells. Secondly, they can act against oncogenic signal transduction pathways, many of which are activated in cancer cells. Some bioactive plant-derived agents are gaining increasing attention because of their anti-cancer properties. Moreover, some naturally-derived compounds can significantly promote the effectiveness of standard chemotherapy drugs, and in certain cases are able to ameliorate drug-induced adverse effects caused by chemotherapy. In the present review we summarize the effects of various naturally-occurring bioactive compounds against osteosarcoma.

Plant isoquinoline alkaloids: Advances in the chemistry and biology of berberine

Alkaloids are one of the most important classes of plant bioactives. Among these isoquinoline alkaloids possess varied structures and exhibit numerous biological activities. Basically these are biosynthetically produced via phenylpropanoid pathway. However, occasionally some mixed pathways may also occur to provide structural divergence. Among the various biological activities anticancer, antidiabetic, antiinflammatory, and antimicrobial are important. A few notable bioactive isoquinoline alkaloids are antidiabetic berberine, anti-tussive codeine, analgesic morphine, and muscle relaxant papaverine etc. Berberine is one of the most discussed bioactives from this class possessing broad-spectrum pharmacological activities. Present review aims at recent updates of isoquinoline alkaloids with major emphasis on berberine, its detailed chemistry, important biological activities, structure activity relationship and implementation in future research.

Synthesis of disaccharide modified berberine derivatives and their anti-diabetic investigation in zebrafish using a fluorescence-based technology

Berberine is a naturally occurring isoquinoline alkaloid and has been used as an important functional food additive in China due to its various pharmacological activities. Berberine exhibits great potential for developing anti-diabetic agents against type 2 diabetes mellitus (T2DM), as it can reduce the blood glucose level in many animal models. However, the low anti-diabetic activity and poor bioavailability of berberine (below 5%) by oral administration significantly limit its practical applications. To solve these problems, this article focuses on the structural modification of berberine using some disaccharide groups, because the carbohydrate moiety has been proved to improve the bioavailability and enhance the receptor-binding affinity of drugs. Anti-diabetic investigation of the synthesized compounds was performed in a zebrafish model using a fluorescently labelled glucose analog 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]-d-glucose (2-NBDG) as a glucose tracker. The results indicated that the modification of berberine with carbohydrate groups could give derivatives with improved anti-diabetic activity, in particular the diglucose modified berberine derivative 1 which could dramatically promote the uptake of 2-NBDG in both zebrafish larvae and their eyes even at very low concentrations. Furthermore, the fluorescence-based anti-diabetic investigation method in zebrafish shows great potential for anti-diabetic drug screening.

An updated review on therapeutic potential and recent advances in drug delivery of Berberine: Current status and future prospect

Natural products are well known for their high potency with minimum side effects. Plant extracts are the most commonly used natural products because of their ease of availability and relatively low production cost. Berberine (BBR), a phytochemical component of some Chinese medicinal herbs (most commonlyBerberis vulgaris), is an isoquinoline alkaloid with several biological and pharmacological effects including antioxidant, anti-inflammatory, antitumour, antimicrobial, antidepressant,hepatoprotective, hypolipidemic, and hypoglycemic actions. Interestingly, multiple studies have shown that BBR is a potential drug candidate with a multi-spectrum therapeutic application. However, the oral delivery of BBR is challenged owing to its poor bioavailability. Therefore, its oral bioavailability needs to be enhanced before it can be used in many clinical applications. This review provides an overview of the various studies that support the broad range of pharmacological activities of BBR. Also, it includes a section to address the issues and challenges related with the drug and methods to improve the properties of BBR such as solubility, stability and bioavailability that may be explored to help patients reap the maximum benefit from this potentially useful drug.

Berberine Improves Glucose and Lipid Metabolism in HepG2 Cells Through AMPKα1 Activation

Aim

This study is designed to investigate whether or not AMP-activated protein kinase α1 (AMPKα1) is required for natural product berberine (BBR) to improve glucose and lipid metabolism in HepG2 cells.

Methods

AMPKα1 knocked-out (KO, AMPKα1^-/-) cells were obtained by co-transfection of the CRISPR/Cas9 KO and HDR (homology-directed repair) plasmid into HepG2 cells, as well as subsequent screen with puromycin. The expression levels of target proteins or mRNAs were determined by western blot or real-time RT-PCR, respectively. Cellular AMPK activity, glucose consumption, lactate release, glucose production, and lipid accumulation were determined by kits.

Results

The results showed that the AMPKα1 gene was successfully KO in HepG2 cells. In AMPKα1^-/- cells, the protein expression of AMPKα1 and phosphorylated-AMPKα1 (p-AMPKα1) disappeared, the level of total AMPKα declined to about 45–50% of wild type (p < 0.01), while p-AMPKα level and AMPK activity were reduced to less than 10% of wild type (p < 0.001). BBR increased p-AMPKα1, p-AMPKα, AMPK activity, and stimulated glucose consumption, lactate release, inhibited glucose production in wild type HepG2 cells (p < 0.05 or p < 0.01). BBR also reduced intracellular lipid accumulation and suppressed the expression of lipogenic genes in oleic acid (OA) treated wild type HepG2 cells (p < 0.05 or p < 0.01). In AMPKα1^-/- HepG2 cells, the stimulating effects of BBR on p-AMPKα1, p-AMPKα, AMPK activity, and its improving effects on glucose and lipid metabolism were completely abolished.

Conclusion

Our study proves that AMPKα1 plays a critical role for BBR to improve glucose and lipid metabolism in HepG2 cells. Our results will provide new information to further understand the molecular mechanisms of BBR.

The Anti-Cancer Mechanisms of Berberine: A Review

Berberine (BBR) has been extensively studied in vivo and vitro experiments. BBR inhibits cell proliferation by regulating cell cycle and cell autophagy, and promoting cell apoptosis. BBR also inhibits cell invasion and metastasis by suppressing EMT and down-regulating the expression of metastasis-related proteins and signaling pathways. In addition, BBR inhibits cell proliferation by interacting with microRNAs and suppressing telomerase activity. BBR exerts its anti-inflammation and antioxidant properties, and also regulates tumor microenvironment. This review emphasized that BBR as a potential anti-inflammation and antioxidant agent, also as an effective immunomodulator, is expected to be widely used in clinic for cancer therapy.

Berberine in the treatment of metabolism-related chronic diseases: A drug cloud (dCloud) effect to target multifactorial disorders

Berberine (BBR) is a multi-target drug (MTD) that has proven effective in the treatment of metabolism-related chronic diseases (CDs). However, the mode of action (MOA) of BBR remains to be clarified. At a cellular level, the inhibitory effect of BBR on mitochondrial enzymes is probably responsible for many of its biological activities, including the activation of low-density lipoprotein receptor (LDLR), AMP-activated protein kinase (AMPK) and insulin receptor (InsR); these biological activities contribute to ameliorate peripheral blood metabolic profiles, e.g. by reducing plasma lipids and glucose levels, thus improving signs and symptoms of metabolic disorders. In this perspective, BBR acts as a targeted therapy. However, it also exerts pleiotropic systemic activities on some root causes of CDs that include antioxidant / anti-inflammatory effects and modifications of gut microbiota composition and metabolism, which may also contribute to its disease-modifying effects. After reviewing the different MOA of BBR, here we propose that BBR acts through a drug-cloud (dCloud) mechanism, as different to a drug-target effect. The dCloud here is defined as a group of terminal molecular events induced by the drug (or/and related metabolites), as well as the network connections among them. In this scenario, the therapeutic efficacy of BBR is the result of its dCloud effect acting on symptoms/signs as well as on root causes of the diseases. The dCloud concept is applicable to other established MTDs, such as aspirin, metformin, statins as well as to nutrient starvation, thus providing a novel instrument for the design of effective therapies against multifactorial metabolism-related CDs.

A novel ASBT inhibitor, IMB17-15, repressed nonalcoholic fatty liver disease development in high-fat diet-fed Syrian golden hamsters

The manipulation of bile acid (BA) homeostasis by blocking the ileal apical Na⁺-dependent bile salt transporter (ASBT/SLC10A2) may have therapeutic effects in nonalcoholic fatty liver disease. We developed a novel ASBT inhibitor, an N-(3,4-o-dichlorophenyl)-2-(3-trifluoromethoxy) benzamide derivative referred to as IMB17-15, and investigated its therapeutic effects and the molecular mechanisms underlying the effects. Syrian golden hamsters were challenged with high-fat diet (HFD) to induce NAFLD and were subsequently administered 400 mg/kg IMB17-15 by gavage daily for 21 days. Serum, liver, and fecal samples were collected for further analysis. Plasma concentration-time profiles of IMB17-15 were also constructed. The human hepatocyte cell line HL-7702 was treated with Oleic acid (OA) with or without IMB17-15. Western blotting and real-time PCR were used to study the molecular mechanisms of IMB17-15. We found that IMB17-15 inhibited ASBT and subsequently suppressed ileal farnesoid X receptor (FXR) and FXR-activated fibroblast growth factor15/19 (FGF15/19) expression, which reduced the hepatic phosphorylated extracellular regulated protein kinase (ERK) and c-Jun N-terminal kinase (JNK) levels and upregulated the cholesterol 7α-hydroxylase (CYP7A1) activity. Additionally, IMB17-15 stimulated adenosine monophosphate (AMP)-activated protein kinase (AMPKα) phosphorylation and enhanced peroxisome proliferator activated receptor α (PPARα) expression and thus promoted triglyceride (TG) oxidation and high-density lipoprotein cholesterol (HDL-c) metabolism through an ASBT-independent mechanism. In conclusion, a novel ASBT inhibitor known as IMB17-15 protected hamsters against HFD-induced NFALD by manipulating BA and lipid homeostasis. IMB17-15 also reduced lipid deposition in human hepatic cell lines, indicating that it may be useful as a therapy for NAFLD patients.

Inhibitory Effect of Berberine on Broiler P-glycoprotein Expression and Function: In Situ and In Vitro Studies

Overcoming P-glycoprotein (P-gp) efflux is a strategy to improve the absorption and pharmacokinetics of its substrate drugs. Berberine inhibits P-gp and thereby increases the bioavailability of the P-gp substrate digoxin in rodents. However, the effects of berberine on P-gp in chickens are still unclear. Here, we studied the role of berberine in modulating broilers P-gp expression and function through both in situ and in vitro models. In addition, molecular docking was applied to analyze the interactions of berberine with P-gp as well as with chicken xenobiotic receptor (CXR). The results showed that the mRNA expression levels of chicken P-gp and CXR decreased in the ileum following exposure to berberine. The absorption rate constant of rhodamine 123 increased after berberine treatment, as detected using an in situ single-pass intestinal perfusion model. Efflux ratios of P-gp substrates (tilmicosin, ciprofloxacin, clindamycin, ampicillin, and enrofloxacin) decreased and the apparent permeability coefficients increased after co-incubation with berberine in MDCK-chAbcb1 cell models. Bidirectional assay results showed that berberine could be transported by chicken P-gp with a transport ratio of 4.20, and this was attenuated by verapamil (an inhibitor of P-gp), which resulted in a ratio of 1.13. Molecular docking revealed that berberine could form favorable interactions with the binding pockets of both CXR and P-gp, with docking scores of −7.8 and −9.5 kcal/mol, respectively. These results indicate that berberine is a substrate of chicken P-gp and down-regulates P-gp expression in chicken tissues, thereby increasing the absorption of P-gp substrates. Our findings suggest that berberine increases the bioavailability of other drugs and that drug-drug interactions should be considered when it is co-administered with other P-gp substrates with narrow therapeutic windows.

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.

Novel carbohydrate modified berberine derivatives: synthesis and in vitro anti-diabetic investigation

Berberine is a bioactive alkaloid used in Chinese medicine and has numerous positive effects on biological systems. This paper describes the facile and highly efficient synthesis of some carbohydrate modified berberine derivatives, and conjugation of the carbohydrate moiety with berberine was finished by "click" chemistry. The cytotoxicity and anti-diabetic measurements of all berberine derivatives were accomplished on HepG2 cell lines, and the results indicated that most of the derivatives exhibit higher anti-diabetic activity than berberine. The mannose modified berberine derivative has significantly lower cytotoxicity than berberine, and the induced IC₅₀ value of this derivative is nearly 1.5 times that of berberine. Furthermore, this mannose modified berberine derivative exhibits high anti-diabetic activity at both high and low drug concentrations, thereby indicating its potential application for the development of novel anti-diabetic drugs.

Different structures of berberine and five other protoberberine alkaloids that affect P-glycoprotein-mediated efflux capacity

Berberine, berberrubine, thalifendine, demethyleneberberine, jatrorrhizine, and columbamine are six natural protoberberine alkaloid (PA) compounds that display extensive pharmacological properties and share the same protoberberine molecular skeleton with only slight substitution differences. The oral delivery of most PAs is hindered by their poor bioavailability, which is largely caused by P-glycoprotein (P-gp)-mediated drug efflux. Meanwhile, P-gp undergoes large-scale conformational changes (from an inward-facing to an outward-facing state) when transporting substrates, and these changes might strongly affect the P-gp-binding specificity. To confirm whether these six compounds are substrates of P-gp, to investigate the differences in efflux capacity caused by their trivial structural differences and to reveal the key to increasing their binding affinity to P-gp, we conducted a series of in vivo, in vitro, and in silico assays. Here, we first confirmed that all six compounds were substrates of P-gp by comparing the drug concentrations in wild-type and P-gp-knockout mice in vivo. The efflux capacity (net efflux) ranked as berberrubine > berberine > columbamine ~ jatrorrhizine > thalifendine > demethyleneberberine based on in vitro transport studies in Caco-2 monolayers. Using molecular dynamics simulation and molecular docking techniques, we determined the transport pathways of the six compounds and their binding affinities to P-gp. The results suggested that at the early binding stage, different hydrophobic and electrostatic interactions collectively differentiate the binding affinities of the compounds to P-gp, whereas electrostatic interactions are the main determinant at the late release stage. In addition to hydrophobic interactions, hydrogen bonds play an important role in discriminating the binding affinities.

Enhancement of Berberine Hypoglycemic Activity by Oligomeric Proanthocyanidins

This study investigated the possible enhancement of berberine’s (BB) hypoglycemic activity by oligomeric proanthocyanidins (OPCs) and its underlying mechanism. The hypoglycemic activity of the studied compounds was evaluated in diabetic db/db mice. The cellular uptake and efflux of BB with or without OPCs were investigated using Caco-2 intestinal cells. A pharmacokinetic study of BB and OPCs was performed in Sprague Dawley (SD) mice by oral administration of the study compounds. Liquid chromatography–tandem mass spectrometry (LC–MS/MS) was employed to determine the cellular efflux, retention, and the serum concentrations of the compounds. The results revealed that OPCs considerably potentiated the hypoglycemic efficacy of BB in diabetic db/db mice. In the in vitro experiments, OPCs significantly inhibited the efflux and increased the uptake of the P-glycoprotein (P-gp) substrate rhodamine-123 (R123) and BB in Caco-2 intestinal cells. Moreover, OPCs substantially reduced the expression of P-gp in Caco-2 cells. The inhibition of BB efflux by OPCs was translated into the improved pharmacokinetics in vivo. When co-administered, OPCs obviously increased the average maximum concentration of BB in mice. In summary, this study demonstrated that combination of BB with OPCs could significantly improve the pharmacokinetics and hypoglycemic efficacy of BB, which is valuable for future exploration of the combination of BB and OPCs as oral hypoglycemic agents.

Use of quercetin in animal feed: effects on the P-gp expression and pharmacokinetics of orally administrated enrofloxacin in chicken

Modulation of P-glycoprotein (P-gp, encoded by Mdr1) by xenobiotics plays central role in pharmacokinetics of various drugs. Quercetin has a potential to modulate P-gp in rodents, however, its effects on P-gp modulation in chicken are still unclear. Herein, study reports role of quercetin in modulation of P-gp expression and subsequent effects on the pharmacokinetics of enrofloxacin in broilers. Results show that P-gp expression was increased in a dose-dependent manner following exposure to quercetin in Caco-2 cells and tissues of chicken. Absorption rate constant and apparent permeability coefficient of rhodamine 123 were decreased, reflecting efflux function of P-gp in chicken intestine increased by quercetin. Quercetin altered pharmacokinetic of enrofloxacin by decreasing area under curve, peak concentration, and time to reach peak concentration and by increasing clearance rate. Molecular docking shows quercetin can form favorable interactions with binding pocket of chicken xenobiotic receptor (CXR). Results provide convincing evidence that quercetin induced P-gp expression in tissues by possible interaction with CXR, and consequently reducing bioavailability of orally administered enrofloxacin through restricting its intestinal absorption and liver/kidney clearance in broilers. The results can be further extended to guide reasonable use of quercetin to avoid drug-feed interaction occurred with co-administered enrofloxacin or other similar antimicrobials.

Retrospective analysis of the effects of a highly standardized mixture of Berberis aristata, Silybum marianum, and monacolins K and KA in diabetic patients with dyslipidemia

BACKGROUND

Berberine, an alkaloid with both glucose- and cholesterol-lowering action, is also characterized by an anti-diarrheal effect. Consequently, berberine-based therapies are recommended for diabetic patients with irritable bowel syndrome (IBS) or gut discomfort caused by metformin.

AIM

As the anti-glycemic and cholesterol-lowering action of berberine is improved by co-administration with P-glycoprotein inhibitors and naturally derived statins, we have analyzed the effect of the food supplement Berberol®K (hereafter referred to as BSM) containing, berberine, silymarin, and a highly standardized red yeast rice containing monacolins K and KA in the ratio 1:1 but no secondary monacolins, dehydromonacolins, or citrinin (Monakopure™-K20).

METHODS

We retrospectively evaluated the effects of BSM in 59 diabetic patients with dyslipidemia and compared the results to those obtained in patients without treatment. Enrolled subjects had a diagnosis of IBS (and diarrhea), had diarrhea caused by metformin, or were statin intolerant.

RESULTS

After 6 months of BSM treatment, significant reductions of approximately 5%, 23%, 31%, and 20% were observed in glycated hemoglobin (HbA1c), total cholesterol (TC), low density lipoprotein-cholesterol (LDL), and triglyceride (TG) levels, respectively, and only five of the 31 treated subjects reported diarrhea compared with 22 of the 28 untreated patients. Regarding safety, treatment with BSM did not significant modify creatine phosphokinase (CPK), creatine, aspartate aminotransferase (AST) or alanine aminotransferase (ALT).

CONCLUSION

BSM is a safe and effective food supplement likely useful as add-on therapy in diabetic subjects with dyslipidemia, especially if they are statin intolerant or with diarrhea caused by IBS or metformin.

Involvement of P-glycoprotein and multidrug and toxin extrusion protein 1 in hepatic and renal berberine efflux in mice

Involvement of P-glycoprotein (P-gp) and multidrug and toxin extrusion protein 1 (MATE1) in the hepatic and renal efflux of berberine was identified using transfected cells, a mouse model, and molecular docking.

Retrospective analysis of the effects of a highly standardized mixture of Berberis aristata, Silybum marianum, and monacolins K and KA in patients with dyslipidemia

BACKGROUND

Berberis aristata, because of its berberine content, and Monascus purpureus fermented rice, because of the presence of monacolins (naturally derived statins), are widely investigated food-grade ingredients used to formulate cholesterol-lowering supplements. Although they are extensively used, berberine is poorly absorbed and monacolins are poorly chemically characterized, not standardized, and possibly contaminated with toxic compounds. Silymarin is reported to enhance berberine absorption, while Monakopure™-K20 (MK-20) is a highly standardized red yeast rice containing monacolins K and KA in the ratio of 1:1 but not secondary monacolins, dehydromonacolins, or citrinin.

AIM

The effects of a cholesterol-lowering supplement (Berberol®K) containing berberine, silymarin, and MK-20 (BSM) in patients with dyslipidemia were clinically analyzed.

METHODS

The clinical role of BSM in naïve and in statin-intolerant patients was retrospectively evaluated and the effects observed were compared with those obtained in patients without treatment or treated with lovastatin.

RESULTS

Total cholesterol, low density lipoprotein, and triglyceride levels were approximately 4%, 6%, and 11% lower, respectively, and the creatine phosphokinase increase was reduced in patients treated with BSM compared to those treated with lovastatin. Similar results were also obtained in statin-intolerant subjects where BSM was administered as add-on therapy to ezetimibe or fenofibrate.

CONCLUSION

BSM is a food supplement potentially useful 1) as a primary intervention in low-cardiovascular-risk subjects with dyslipidemia; 2) as add-on therapy in mildly statin-intolerant patients; and 3) in dyslipidemic patients with a negative perception of statins who prefer a treatment seen as natural.

Insights into the Role and Interdependence of Oxidative Stress and Inflammation in Liver Diseases

The crucial roles of oxidative stress and inflammation in the development of hepatic diseases have been unraveled and emphasized for decades. From steatosis to fibrosis, cirrhosis and liver cancer, hepatic oxidative stress, and inflammation are sustained and participated in this pathological progressive process. Notably, increasing evidences showed that oxidative stress and inflammation are tightly related, which are regarded as essential partners that present simultaneously and interact with each other in various pathological conditions, creating a vicious cycle to aggravate the hepatic diseases. Clarifying the interaction of oxidative stress and inflammation is of great importance to provide new directions and targets for developing therapeutic intervention. Herein, this review is concerned with the regulation and interdependence of oxidative stress and inflammation in a variety of liver diseases. In addition to classical mediators and signaling, particular emphasis is placed upon immune suppression, a potential linkage of oxidative stress and inflammation, to provide new inspiration for the treatment of liver diseases. Furthermore, since antioxidation and anti-inflammation have been extensively attempted as the strategies for treatment of liver diseases, the application of herbal medicines and their derived compounds that protect liver from injury via regulating oxidative stress and inflammation collectively were reviewed and discussed.

Clinical role of a fixed combination of standardized Berberis aristata and Silybum marianum extracts in diabetic and hypercholesterolemic patients intolerant to statins

BACKGROUND

Statin intolerance is a medical condition often leading patients to nonadherence to the prescribed therapy or to a relevant reduction of the statin dosage. Both situations determine a totally or partially uncontrolled lipid profile, and these conditions unquestionably increase the risk of cardiovascular events.

METHODS

We enrolled hypercholesterolemic, type 2 diabetic patients complaining of intolerance to statins. Some of them had reduced the statin dose 'until the disappearance of symptoms'; others had opted for treatment with ezetimibe; and yet others were not undergoing any treatment at all. All patients of the three groups were then given a fixed combination of berberine and silymarin (Berberol(®)), known from previous papers to be able to control both lipidic and glycemic profiles.

RESULTS

The tested product both as a single therapy and as add-on therapy to low-dose statin or to ezetimibe reduced triglycerides, low-density lipoprotein cholesterol, fasting blood glucose, and glycosylated hemoglobin in a significant manner without inducing toxicity conditions that might be somehow ascribed to a statin-intolerant condition.

CONCLUSION

Our study demonstrates that use of Berberol(®), administered as a single or add-on therapy in statin-intolerant subjects affected by diabetes and hypercholesterolemia is a safe and effective tool capable of improving the patients' lipidic and glycemic profiles.

Preliminary study about the possible glycemic clinical advantage in using a fixed combination of Berberis aristata and Silybum marianum standardized extracts versus only Berberis aristata in patients with type 2 diabetes

Background

Berberine is an isoquinoline alkaloid widely used to improve the glucidic and lipidic profiles of patients with hypercholesterolemia, metabolic syndrome, and type 2 diabetes. The limitation of berberine seems to be its poor oral bioavailability, which is affected by the presence, in enterocytes, of P-glycoprotein – an active adenosine triphosphate (ATP)-consuming efflux protein that extrudes berberine into the intestinal lumen, thus limiting its absorption. According to some authors, silymarin, derived from Silybum marianum, could be considered a P-glycoprotein antagonist.

Aim

The study aimed to evaluate the role played by a possible P-glycoprotein antagonist (silymarin), when added to a product containing Berberis aristata extract, in terms of benefits to patients with type 2 diabetes.

Methods

The study enrolled 69 patients with type 2 diabetes in suboptimal glycemic control who were treated with diet, hypoglycemic drugs, and in cases of concomitant alterations of the lipid profile, hypolipidemic agents. The patients received an add-on therapy consisting of either a standardized extract of Berberis aristata (titrated in 85% berberine) corresponding to 1,000 mg/day of berberine, or Berberol®, a fixed combination containing the same standardized extract of Berberis aristata plus a standardized extract of Silybum marianum (titrated as >60% in silymarin), for a total intake of 1,000 mg/day of berberine and 210 mg/day of silymarin.

Results

Both treatments similarly improved fasting glucose, total cholesterol, low-density lipoprotein (LDL) cholesterol, triglyceride, and liver enzyme levels, whereas glycosylated hemoglobin (HbA_1c) values were reduced to a greater extent by the fixed combination.

Conclusion

The association of berberine and silymarin demonstrated to be more effective than berberine alone in reducing HbA_1c, when administered at the same dose and in the form of standardized extracts in type 2 diabetic patients.