Enhanced Intestinal Absorption and Pharmacokinetic Modulation of Berberine and Its Metabolites through the Inhibition of P-Glycoprotein and Intestinal Metabolism in Rats Using a Berberine Mixed Micelle Formulation

Oral Administration of Berberine Hydrochloride Based on Chitosan/Carboxymethyl-β-Cyclodextrin Hydrogel

In this study, a novel oral formulation of berberine hydrochloride (BBH) hydrogel was successfully synthesized through physical cross-linking using chitosan (CS) and carboxymethyl-β-cyclodextrin (CMCD). The characterization results confirmed the successful synthesis of the CS/CMCD hydrogel and the subsequent loading of BBH into this composite (CS/CMCD/BBH) was effectively accomplished. The BBH was used as a model drug and the resulting hydrogel demonstrated a sustained drug release profile. In addition to its improved solubility and sustained release characteristics, the hydrogel exhibited excellent antibacterial activity against common pathogens such as Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Candida albicans (C. albicans). Additionally, in vitro studies indicated that the hydrogel was not cytotoxic to NIH3T3 and HaCaT cells, suggesting its safety for biomedical applications. This lack of cytotoxic effects, combined with the mechanical strength, solubility improvements, and antibacterial properties of the hydrogel, positions the CS/CMCD/BBH hydrogel as a promising candidate for the effective oral delivery of BBH. By addressing the solubility and delivery challenges of BBH, this hydrogel offers a viable solution for the oral administration of BBH, with potential applications in various biomedical fields.

Pharmacokinetics and Enterohepatic Circulation of 2-(Quinoline-8-carboxamido)benzoic Acid (2-QBA) in Mice

The quinoline alkaloid 2-(quinoline-8-carboxamido)benzoic acid (2-QBA), which is isolated from Aspergillus sp. SCSIO06786, a deep sea-derived fungus, has been suggested as a therapeutic candidate for the treatment of Parkinson's disease. We developed an analytical method for 2-QBA using a liquid chromatography-tandem mass spectrometry (LC-MS/MS) in mouse plasma, in which a protein precipitation method for the sample preparation of 2-QBA in mouse plasma was used due to its simplicity and good extraction recovery rates (80.49-97.56%). The linearity of the calibration standard sample, inter- and intraday precision and accuracy, and stability of three quality control samples were suitable based on the assessment criteria and the lower limit of quantification (LLOQ) of the 2-QBA was 1 ng/mL. A pharmacokinetic study of 2-QBA was performed in mice divided into oral (2.0, 5.0, and 15 mg/kg) and intravenous (0.5 and 1.0 mg/kg) administration groups. The absolute oral bioavailability (BA) range of 2-QBA was calculated as 68.3-83.7%. Secondary peaks were observed at approximately 4-8 h after the oral administration of 2-QBA at all doses. The elimination half-life of the orally administered 2-QBA was significantly longer than that of the intravenous 2-QBA. In addition, glucuronide metabolites of 2-QBA were identified. They were transformed into 2-QBA using the β-glucuronidase treatment. Furthermore, the 2-QBA was readily absorbed from the jejunum to lower ileum. Taken together, the secondary peaks could be explained by the enterohepatic circulation of 2-QBA. In conclusion, the reabsorption of orally administered 2-QBA could contribute to the high oral BA of 2-QBA and could be beneficial for the efficacy of 2-QBA. Moreover, the simple and validated analytical method for 2-QBA using LC-MS/MS was applied to the pharmacokinetic study and BA assessments of 2-QBA in mice and would be helpful for subsequent pharmacokinetic studies, as well as for evaluations of the toxicokinetics and pharmacokinetic-pharmacodynamic correlation of 2-QBA to assess its potential as a drug.

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 ameliorates glucocorticoid-induced hyperglycemia: an in vitro and in vivo study

Berberine (BBR), a bioactive compound isolated from Coptidis Rhizoma, possesses diverse pharmacological activities including anti-bacterial, anti-inflammatory, antitumor, hypolipidemic, and anti-diabetic. However, its role as an anti-diabetic agent in animal models of dexamethasone (Dex)-induced diabetes remains unknown. Studies have shown that natural compounds including aloe, caper, cinnamon, cocoa, green and black tea, and turmeric can be used for treating Type 2 diabetes mellitus (DM). Compared to conventional drugs, natural compounds have less side effects and are easily available. Herein, we studied the anti-diabetic effects of BBR in a mice model of Dex-induced diabetes. HepG2 cell line was used for glucose release and glycogen synthesis studies. Cell proliferation was measured by methylthiotetrazole (MTT) assay. For animal studies, mice were treated with Dex (2 mg/kg, i.m.) for 30 days and effect of BBR at the doses 100, 200, and 500 mg/kg (p.o.) was analyzed. Glucose, insulin, and pyruvate tests were performed for evaluating the development of the diabetic model. Echo MRI was performed to assess the fat mass. Further, to elucidate the mechanism of action of BBR, mRNA expression of genes regulating gluconeogenesis, glucose uptake, and glycolysis was analyzed. In vitro BBR had no impact on cell viability up to a concentration of 50 μM. Moreover, BBR suppressed the hepatic glucose release and improved glucose tolerance in HepG2 cells. In vivo, BBR improved glucose homeostasis in diabetic mice as evidenced by enhanced glucose clearance, increased glycolysis, elevated glucose uptake, and decreased gluconeogenesis. Further, Dex treatment increased the total fat mass in mice, which was ameliorated by BBR treatment. BBR improves glucose tolerance by increasing glucose clearance, inhibiting hepatic glucose release, and decreasing obesity. Thus, BBR may become a potential therapeutic agent for treating glucocorticoid-induced diabetes and obesity in the future.

Berberine-silybin salt achieves improved anti-nonalcoholic fatty liver disease effect through regulating lipid metabolism

ETHNOPHARMACOLOGICAL RELEVANCE

Berberine (BBR) and silybin (SIY) are natural compounds obtained from Berberidaceae members and Silybum marianum (L.) Gaertn., respectively. These compounds have been demonstrated to regulate lipid metabolism and indue hepatoprotective effects, establishing their importance for the treatment of liver injury. Combination therapy has shown promise in treating ailments with complex pathophysiology, such as liver diseases. However, the inconsistent dissolution and poor absorption of BBR and SIY limit their efficacy.

AIM OF THE STUDY

This study compared the salt formulation (BSS) and physical mixture (BSP) of BBR and SIY for their efficacy in treating nonalcoholic fatty liver disease (NAFLD).

MATERIALS AND METHODS

The formation of the BSS was confirmed using various techniques, including nuclear magnetic resonance spectroscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy, and powder X-ray diffractometry. In addition, dissolution, trans-epithelial permeability, and bioavailability experiments were conducted to evaluate the absorption and distribution of drugs. Pharmacodynamics and mechanisms were investigated through in vivo experiments.

RESULTS

BSS form demonstrated synchronized dissolution of both components, unlike BSP. Additionally, the transepithelial permeability results revealed that BSS exhibited superior penetration and absorption of both BBR and SIY in comparison to BSP. Furthermore, BSS significantly increased the bioavailability of SIY in both plasma and the liver (2.2- and 4.5-fold, respectively) when compared with BSP. Moreover, BSS demonstrated a more potent inhibitory effect on lipid production in HepG2 cells than BSP. In mouse models (BALB/c) of NAFLD, BSS improved disease outcomes, as evidenced by decreased adipose levels, normalized blood lipid levels, and reduced liver parenchyma injury. Preliminary transcriptomics analysis suggested that BSS achieved its anti-NAFLD effect by regulating the expression of fatty acid transporter CD36, recombinant fatty acid binding protein 4, and stearyl coenzyme A dehydrogenase 1, which are associated with the synthesis and uptake of fatty acid-related proteins.

CONCLUSIONS

The study demonstrated that compared with physical mixing, salification improved the efficacy of BBR and SIY, as demonstrated in animal experiments. These findings provide valuable insights into the development of more effective treatments for NAFLD and provide new possibilities for combination therapies.

Research progress on antidepressant effects and mechanisms of berberine

Depression, a global health problem with growing prevalence, brings serious impacts on the daily life of patients. However, the antidepressants currently used in clinical are not perfectly effective, which greatly reduces the compliance of patients. Berberine is a natural quaternary alkaloid which has been shown to have a variety of pharmacological effects, such as hypoglycemic, lipid-regulation, anti-cancer, antibacterial, anti-oxidation, anti-inflammatory, and antidepressant. This review summarizes the evidence of pharmacological applications of berberine in treating depression and elucidates the mechanisms of berberine regulating neurotransmitter levels, promoting the regeneration of hippocampal neurons, improving hypothalamic-pituitary-adrenal axis dysfunction, anti-oxidative stress, and suppressing inflammatory status in order to provide a reference for further research and clinical application of berberine.

Investigation of Antioxidant and Anti-inflammatory Properties of Berberine Nanomicelles: In vitro and In vivo Studies

INTRODUCTION

In the present study, neuroprotective effects of berberine (BBR) and berberine nanomicelle (BBR-NM) against lipopolysaccharides (LPS)-induced stress oxidative were investigated, and compared by evaluating their antioxidant and anti-inflammatory activities in PC12 cells, and rat brains. A fast, green, and simple synthesis method was used to prepare BBR-NMs.

METHOD

The prepared BBR-NMs were then characterized using dynamic light scattering (DLS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). In vitro experiments were carried out on the LPS-treated PC12 cell lines to investigate the anti-cytotoxic and antioxidant properties of BBR-NM and BBR. The results showed that BBR-NMs with a diameter of ~100 nm had higher protective effects against ROS production and cytotoxicity induced by LPS in PC12 cells in comparison with free BBR.

RESULTS

Moreover, in vivo experiments indicated that the activity levels of antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), increased in the brain of LPS-treated rats administrated with BBR-NM at the optimum dose of 100 mg.kg-1. BBR-NM administration also resulted in decreased concentration of lipid peroxidation (MDA) and pro-inflammatory cytokines, such as Serum interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α).

CONCLUSION

Overall, BBR-NM demonstrated higher neuroprotective effects than free BBR, making it a promising treatment for improving many diseases caused by oxidative stress and inflammation.

Berberine-microbiota interplay: orchestrating gut health through modulation of the gut microbiota and metabolic transformation into bioactive metabolites

Berberine is an isoquinoline alkaloid found in plants. It presents a wide range of pharmacological activities, including anti-inflammatory and antioxidant properties, despite a low oral bioavailability. Growing evidence suggests that the gut microbiota is the target of berberine, and that the microbiota metabolizes berberine to active metabolites, although little evidence exists in the specific species involved in its therapeutic effects. This study was performed to detail the bidirectional interactions of berberine with the broiler chicken gut microbiota, including the regulation of gut microbiota composition and metabolism by berberine and metabolization of berberine by the gut microbiota, and how they contribute to berberine-mediated effects on gut health. As previous evidence showed that high concentrations of berberine may induce dysbiosis, low (0.1 g/kg feed), middle (0.5 g/kg feed) and high (1 g/kg feed) doses were here investigated. Low and middle doses of in-feed berberine stimulated potent beneficial bacteria from the Lachnospiraceae family in the large intestine of chickens, while middle and high doses tended to increase villus length in the small intestine. Plasma levels of the berberine-derived metabolites berberrubine, thalifendine and demethyleneberberine were positively correlated with the villus length of chickens. Berberrubine and thalifendine were the main metabolites of berberine in the caecum, and they were produced in vitro by the caecal microbiota, confirming their microbial origin. We show that members of the genus Blautia could demethylate berberine into mainly thalifendine, and that this reaction may stimulate the production of short-chain fatty acids (SCFAs) acetate and butyrate, via acetogenesis and cross-feeding respectively. We hypothesize that acetogens such as Blautia spp. are key bacteria in the metabolization of berberine, and that berberrubine, thalifendine and SCFAs play a significant role in the biological effect of berberine.

Oral administration of Huanglian-Houpo herbal nanoemulsion loading multiple phytochemicals for ulcerative colitis therapy in mice

How to achieve stable co-delivery of multiple phytochemicals is a common problem. This study focuses on the development, optimization and characterization of Huanglian-HouPo extract nanoemulsion (HLHPEN), with multiple components co-delivery, to enhance the anti-ulcerative colitis (UC) effects. The formulation of HLHPEN was optimized by pseudo-ternary phase diagram combined with Box-Behnken design. The physicochemical properties of HLHPEN were characterized, and its anti-UC activity was evaluated in DSS-induced UC mice model. Based on preparation process optimization, the herbal nanoemulsion HLHPEN was obtained, with the droplet size, PDI value, encapsulation efficiency (EE) for 6 phytochemicals (berberine, epiberberine, coptisine, bamatine, magnolol and honokiol) of 65.21 ± 0.82 nm, 0.182 ± 0.016, and 90.71 ± 0.21%, respectively. The TEM morphology of HLHPEN shows the nearly spheroidal shape of particles. The optimized HLHPEN showed a brownish yellow milky single-phase and optimal physical stability at 25 °C for 90 days. HLHPEN exhibited the good particle stability and gradual release of phytochemicals in SGF and SIF, to resist the destruction of simulated stomach and small intestine environment. Importantly, the oral administration of HLHPEN significantly restored the shrunk colon tissue length and reduced body weight, ameliorated DAI value and colon histological pathology, decreased the levels of inflammatory factors in DSS-induced UC mice model. These results demonstrated that HLHPEN had a significant therapeutic effect on DSS-induced UC mice, as a potential alternative UC therapeutic agent.

Efficacy and underlying mechanisms of berberine against lipid metabolic diseases: a review

Lipid-lowering therapy is an important tool for the treatment of lipid metabolic diseases, which are increasing in prevalence. However, the failure of conventional lipid-lowering drugs to achieve the desired efficacy in some patients, and the side-effects of these drug regimens, highlight the urgent need for novel lipid-lowering drugs. The liver and intestine are important in the production and removal of endogenous and exogenous lipids, respectively, and have an important impact on circulating lipid levels. Elevated circulating lipids predisposes an individual to lipid deposition in the vascular wall, affecting vascular function. Berberine (BBR) modulates liver lipid production and clearance by regulating cellular targets such as cluster of differentiation 36 (CD36), acetyl-CoA carboxylase (ACC), microsomal triglyceride transfer protein (MTTP), scavenger receptor class B type 1 (SR-BI), low-density lipoprotein receptor (LDLR), and ATP-binding cassette transporter A1 (ABCA1). It influences intestinal lipid synthesis and metabolism by modulating gut microbiota composition and metabolism. Finally, BBR maintains vascular function by targeting proteins such as endothelial nitric oxide synthase (eNOS) and lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1). This paper elucidates and summarizes the pharmacological mechanisms of berberine in lipid metabolic diseases from a multi-organ (liver, intestine, and vascular system) and multi-target perspective.

Study Models of Drug-Drug Interactions Involving P-Glycoprotein: The Potential Benefit of P-Glycoprotein Modulation at the Kidney and Intestinal Levels

P-glycoprotein (P-gp) is a crucial membrane transporter situated on the cell's apical surface, being responsible for eliminating xenobiotics and endobiotics. P-gp modulators are compounds that can directly or indirectly affect this protein, leading to changes in its expression and function. These modulators can act as inhibitors, inducers, or activators, potentially causing drug-drug interactions (DDIs). This comprehensive review explores diverse models and techniques used to assess drug-induced P-gp modulation. We cover several approaches, including in silico, in vitro, ex vivo, and in vivo methods, with their respective strengths and limitations. Additionally, we explore the therapeutic implications of DDIs involving P-gp, with a special focus on the renal and intestinal elimination of P-gp substrates. This involves enhancing the removal of toxic substances from proximal tubular epithelial cells into the urine or increasing the transport of compounds from enterocytes into the intestinal lumen, thereby facilitating their excretion in the feces. A better understanding of these interactions, and of the distinct techniques applied for their study, will be of utmost importance for optimizing drug therapy, consequently minimizing drug-induced adverse and toxic effects.

Characterization and Pharmacokinetic Assessment of a New Berberine Formulation with Enhanced Absorption In Vitro and in Human Volunteers

Berberine is a plant-origin quaternary isoquinoline alkaloid with a vast array of biological activities, including antioxidant and blood-glucose- and blood-lipid-lowering effects. However, its therapeutic potential is largely limited by its poor oral bioavailability. The aim of this study was to investigate the in vitro solubility and Caco-2 cell permeability followed by pharmacokinetic profiling in healthy volunteers of a new food-grade berberine delivery system (i.e., Berberine LipoMicel®). X-ray diffractometry (XRD), in vitro solubility, and Caco-2 cell permeability indicated higher bioavailability of LipoMicel Berberine (LMB) compared to the standard formulation. Increased aqueous solubility (up to 1.4-fold), as well as improved Caco-2 cell permeability of LMB (7.18 × 10-5 ± 7.89 × 10-6 cm/s), were observed when compared to standard/unformulated berberine (4.93 × 10-6 ± 4.28 × 10-7 cm/s). Demonstrating better uptake, LMB achieved significant increases in AUC0-24 and Cmax compared to the standard formulation (AUC: 78.2 ± 14.4 ng h/mL vs. 13.4 ± 1.97 ng h/mL, respectively; p < 0.05; Cmax: 15.8 ± 2.6 ng/mL vs. 1.67 ± 0.41 ng/mL) in a pilot study of healthy volunteers (n = 10). No adverse reactions were reported during the study period. In conclusion, LMB presents a highly bioavailable formula with superior absorption (up to six-fold) compared to standard berberine formulation and may, therefore, have the potential to improve the therapeutic efficacy of berberine. The study has been registered on ClinicalTrials.gov with Identifier NCT05370261.

Berberine improves DSS-induced colitis in mice by modulating the fecal-bacteria-related bile acid metabolism

Ulcerative colitis (UC) has been confirmed as a disease with a high incidence and low cure rate worldwide. In severe cases, UC can develop into colon cancer. Modern research has confirmed that berberine (BBR) can treat UC by inhibiting the expressions of inflammatory factors. However, the contribution of gut microbiota and flora metabolites in treating UC with BBR remains unclear. In this study, the ameliorative effects of BBR on gut microbiota dysbiosis and flora metabolites were investigated in a dextran sodium sulfate (DSS)-induced UC rodent model. We found that BBR significantly improved the pathological phenotype, attenuated intestinal barrier disruption, and mitigated colonic inflammation in DSS mice. By 16 S rDNA sequencing, BBR alleviated gut microbiota dysbiosis in UC mice. Moreover, the gut microbiota depletion experiment confirmed that the therapeutic effect of BBR was inextricably correlated with the gut microbiota. Besides, the flora metabolites (e.g., short-chain fatty acids, bile acids, and 5-hydroxytryptamine) were studied using HPLC-MS. The results suggested that BBR ameliorated the bile acid imbalance induced by DSS in the liver and gut. Furthermore, BBR treatment repaired gut barrier damage. The above results revealed that BBR alleviated DSS-induced UC in mice by restoring the disturbed gut microbiota, elevating unconjugated and secondary bile acids in the gastrointestinal tract, and activating the FXR and TGR5 signal pathway. This study provides novel insights into the mechanism of BBR in treating UC.

A Promising Approach to Treat Psoriasis: Inhibiting Cytochrome P450 3A4 Metabolism to Enhance Desoximetasone Therapy

(1) Background: Human keratinocytes and murine skin express various cytochrome P450 enzymes. These include cytochrome P450 3A4, which may participate in the metabolism of cytochrome P450 3A4 substrate drugs. Desoximetasone, a topical corticosteroid and cytochrome P450 3A4 substrate, is used to treat skin conditions such as skin allergies, atopic dermatitis, and psoriasis. In this study, we aimed to investigate the anti-psoriatic effect of a low dose of desoximetasone by inhibiting cytochrome P450 3A4 metabolism in the epidermis. (2) Methods: Psoriasis-like skin was induced in BALB/c mice via the topical administration of imiquimod. The mice were then topically treated with 0.01-0.05% desoximetasone loaded into a cytochrome P450 3A4 enzyme inhibitor excipient base emollient microemulsion, 0.25% commercial desoximetasone ointment, or 0.5 mg/gm clobetasol ointment. (3) Results: The topical application of 0.05% desoximetasone loaded into a cytochrome P450 3A4 enzyme inhibitor excipient base emollient formulation restored the imiquimod-induced skin barrier disruption and resulted in fewer severe clinical and pathological features compared with the treatments with 0.25% commercial desoximetasone ointment and 0.5 mg/gm clobetasol ointment. (4) Conclusions: The cytochrome P450 3A4 enzyme inhibitor excipient base emollient formulation improved and prolonged the therapeutic effect of cytochrome P450 3A4 substrate drugs and may be a promising approach for psoriasis treatment.

Current understanding and future prospects on Berberine for anticancer therapy

Berberine (BBR) is a potential plant metabolite and has remarkable anticancer properties. Many kinds of research are being focused on the cytotoxic activity of berberine in in vitro and in vivo studies. A variety of molecular targets which lead to the anticancer effect of berberine ranges from p-53 activation, Cyclin B expression for arresting cell cycles; protein kinase B (AKT), MAP kinase and IKB kinase for antiproliferative activity; effect on beclin-1 involved in autophagy; reduced expression of MMP-9 and MMP-2 for the inhibition of invasion and metastasis etc. Berberine also interferes with transcription factor-1 (AP-1) activity responsible for the expression of oncogenes and neoplastic transformation of the cell. It also leads to the inhibition of various enzymes which are directly or indirectly involved in carcinogenesis like N acetyl transferase, Cyclo-oxygenase-2, Telomerase and Topoisomerase. In addition to these actions, Berberine plays a role in, the regulation of reactive oxygen species and inflammatory cytokines in preventing cancer formation. Berberine anticancer properties are demonstrated due to the interaction of berberine with micro-RNA. The summarized information presented in this review article may help and lead the researchers, scientists/industry persons to use berberine as a promising candidate against cancer.

Recent Advances in Doxorubicin Formulation to Enhance Pharmacokinetics and Tumor Targeting

Doxorubicin (DOX), a widely used drug in cancer chemotherapy, induces cell death via multiple intracellular interactions, generating reactive oxygen species and DNA-adducted configurations that induce apoptosis, topoisomerase II inhibition, and histone eviction. Despite its wide therapeutic efficacy in solid tumors, DOX often induces drug resistance and cardiotoxicity. It shows limited intestinal absorption because of low paracellular permeability and P-glycoprotein (P-gp)-mediated efflux. We reviewed various parenteral DOX formulations, such as liposomes, polymeric micelles, polymeric nanoparticles, and polymer-drug conjugates, under clinical use or trials to increase its therapeutic efficacy. To improve the bioavailability of DOX in intravenous and oral cancer treatment, studies have proposed a pH- or redox-sensitive and receptor-targeted system for overcoming DOX resistance and increasing therapeutic efficacy without causing DOX-induced toxicity. Multifunctional formulations of DOX with mucoadhesiveness and increased intestinal permeability through tight-junction modulation and P-gp inhibition have also been used as orally bioavailable DOX in the preclinical stage. The increasing trends of developing oral formulations from intravenous formulations, the application of mucoadhesive technology, permeation-enhancing technology, and pharmacokinetic modulation with functional excipients might facilitate the further development of oral DOX.

Impact of nanotechnology on the oral delivery of phyto-bioactive compounds

Nanotechnology is an advanced field that has remarkable nutraceutical and food applications. Phyto-bioactive compounds (PBCs) play critical roles in promoting health and disease treatment. However, PBCs generally encounter several limitations that delay their widespread application. For example, most PBCs have low aqueous solubility, poor biostability, poor bioavailability, and a lack of target specificity. Moreover, the high concentrations of effective PBC doses also limit their application. As a result, encapsulating PBCs into an appropriate nanocarrier may increase their solubility and biostability and protect them from premature degradation. Moreover, nanoencapsulation could improve absorption and prolong circulation with a high opportunity for targeted delivery that may decrease unwanted toxicity. This review addresses the main parameters, variables, and barriers that control and affect oral PBC delivery. Moreover, this review discusses the potential role of biocompatible and biodegradable nanocarriers in improving the water solubility, chemical stability, bioavailability, and specificity/selectivity of PBCs.

Approaching strategy to increase the oral bioavailability of berberine, a quaternary ammonium isoquinoline alkaloid: Part 2. Development of oral dosage formulations

INTRODUCTION

Berberine (BBR) possesses a wide variety of pharmacological activities. However, the oral bioavailability of BBR is low due to extensive intestinal first-pass metabolism by cytochrome P450s (CYPs), insufficient absorption due to low solubility and P-glycoprotein (P-gp)-mediated efflux transport, and hepatic first-pass metabolism in rats.

AREAS COVERED

Various dosage formulations were developed to increase the oral bioavailability of BBR by overcoming the reducing factors. This article provides the developing strategy of oral dosage formulations of BBR based on the physicochemical (low solubility, formation of salts/ion-pair complex) and pharmacokinetic properties (substrate of P-gp/CYPs, extensive intestinal first-pass metabolism). Literature was searched by using PubMed.

EXPERT OPINION

Here, formulations increasing the dissolution rates/solubility; formulations containing a P-gp inhibitor; formulations containing solubilizer exhibiting P-gp and/or CYPs inhibitors; formulations containing absorption enhancers; gastro/duodenal retentive formulations; lipid-based formulations; formulations targeting lymphatic transport; and physicochemical modifications increasing lipophilicity were reviewed. Among these formulations, formulations that can reduce intestinal first-pass metabolisms such as formulations containing CYPs inhibitor(s) and formulations containing absorption enhancer(s) significantly increased the oral bioavailability of BBR. Further studies on other dosing routes that can avoid first-pass metabolism such as the rectal route would also be important to increase the bioavailability of BBR.

A Review of Fibraurea tinctoria and Its Component, Berberine, as an Antidiabetic and Antioxidant

Diabetes mellitus is a group of metabolic disorders characterized by hyperglycemia caused by resistance to insulin action, inadequate insulin secretion, or excessive glucagon production. Numerous studies have linked diabetes mellitus and oxidative stress. People with diabetes usually exhibit high oxidative stress due to persistent and chronic hyperglycemia, which impairs the activity of the antioxidant defense system and promotes the formation of free radicals. Recently, several studies have focused on exploring natural antioxidants to improve diabetes mellitus. Fibraurea tinctoria has long been known as the native Borneo used in traditional medicine to treat diabetes. Taxonomically, this plant is part of the Menispermaceae family, widely known for producing various alkaloids. Among them are protoberberine alkaloids such as berberine. Berberine is an isoquinoline alkaloid with many pharmacological activities. Berberine is receiving considerable interest because of its antidiabetic and antioxidant activities, which are based on many biochemical pathways. Therefore, this review explores the pharmacological effects of Fibraurea tinctoria and its active constituent, berberine, against oxidative stress and diabetes, emphasizing its mechanistic aspects. This review also summarizes the pharmacokinetics and toxicity of berberine and in silico studies of berberine in several diseases and its protein targets.

Berberine-A Promising Therapeutic Approach to Polycystic Ovary Syndrome in Infertile/Pregnant Women

Polycystic ovary syndrome (PCOS) is a disorder with an unknown etiology that features a wide range of endocrine and metabolic abnormalities that hamper fertility. PCOS women experience difficulties getting pregnant, and if pregnant, they are prone to miscarriage, gestational diabetes, pregnancy-induced hypertension and preeclampsia, high fetal morbidity, and perinatal mortality. Insulin, the pancreatic hormone best known for its important role in glucose metabolism, has an underrated position in reproduction. PCOS women who have associated insulin resistance (with consequent hyperinsulinemia) have fertility issues and adverse pregnancy outcomes. Lowering the endogen insulin levels and insulin resistance appears to be a target to improve fertility and pregnancy outcomes in those women. Berberine is an alkaloid with a high concentration in various medicinal herbs that exhibits a hypoglycaemic effect alongside a broad range of other therapeutic activities. Its medical benefits may stand up for treating different conditions, including diabetes mellitus. So far, a small number of pharmacological/clinical trials available in the English language draw attention towards the good results of berberine's use in PCOS women with insulin resistance for improving fertility and pregnancy outcomes. Our study aims to uncover how berberine can counteract the negative effect of insulin resistance in PCOS women and improve fertility and pregnancy outcomes.

Concomitant Administration of Red Ginseng Extract with Lactic Acid Bacteria Increases the Plasma Concentration of Deglycosylated Ginsenosides in Healthy Human Subjects

With the increased frequency of red ginseng extract (RGE) and lactic acid bacteria (LAB) co-administration, we aimed to investigate the interactions between RGE and LAB with regard to in vitro and in vivo deglycosylation metabolism and the pharmacokinetics of ginsenosides. As a proof-of-concept study, five healthy humans were administered RGE (104.1 mg of total ginsenosides/day) with or without co-administration of LAB (2 g, 1 billion CFU/day) for 2 weeks, and the plasma concentrations of ginsenosides in human plasma were monitored. The plasma exposure to compound K (CK), ginsenoside Rh2 (GRh2), protopanaxadiol (PPD), and protopanaxatriol (PPT) in the concomitant administration RGE and LAB groups increased by 2.7-, 2.1-, 1.6-, and 3.5-fold, respectively, compared to those in the RGE administration group, without a significant change in T_max. The plasma concentrations of GRb1, GRb2, and GRc remained unchanged, whereas the AUC values of GRd and GRg3 significantly decreased in the concomitant administration RGE and LAB groups. To understand the underlying mechanism, the in vitro metabolic activity of ginsenosides was measured during the fermentation of RGE or individual ginsenosides in the presence of LAB for 1 week. Consistent with the in vivo results, co-incubation with RGE and LAB significantly increased the formation rate of GRh2, CK, PPD, and PPT. These results may be attributed to the facilitated deglycosylation of GRd and GRg3 and the increased production of GRh2, CK, PPD, and PPT by the co-administration of LAB and RGE. In conclusion, LAB supplementation increased the plasma concentrations of deglycosylated ginsenosides, such as GRh2, CK, PPD, and PPT, through facilitated deglycosylation metabolism of ginsenosides in the intestine.

Pharmacokinetic of berberine, the main constituent of Berberis vulgaris L.: A comprehensive review

Barberry (Berberis vulgaris L.) is a medicinal plant and its main constituent is an isoquinoline alkaloid named berberine that has multiple pharmacological effects such as antioxidant, anti-microbial, antiinflammatory, anticancer, anti-diabetes, anti-dyslipidemia, and anti-obesity. However, it has restricted clinical uses due to its very poor solubility and bioavailability (less than 1%). It undergoes demethylenation, reduction, and cleavage of the dioxymethylene group in the first phase of metabolism. Its phase two reactions include glucuronidation, sulfation, and methylation. The liver is the main site for berberine distribution. Berberine could excrete in feces, urine, and bile. Fecal excretion of berberine (11-23%) is higher than urinary and biliary excretion routes. However, a major berberine metabolite is excreted in urine greater than in feces. Concomitant administration of berberine with other drugs such as metformin, cyclosporine A, digoxin, etc. may result in important interactions. Thus, in this review, we gathered and dissected any related animal and human research articles regarding the pharmacokinetic parameters of berberine including bioavailability, metabolism, distribution, excretion, and drug-drug interactions. Also, we discussed and gathered various animal and human studies regarding the developed products of berberine with better bioavailability and consequently, better therapeutic effects.

Enhanced bioavailability and hepatoprotective effect of silymarin by preparing silymarin-loaded solid dispersion formulation using freeze-drying method

This study aimed to develop a solid dispersion formulation of silymarin (Silymarin-SD) using freeze-drying method to enhance its oral bioavailability (BA) by inhibiting the intestinal first-pass effect and increasing its solubility and permeability. Silymarin-SD formulation (i.e., silymarin:tween 80:hydroxypropyl cellulose (HPC) = 1:1:3 (w/w/w) significantly increased silymarin permeability in the duodenum, jejunum, and ileum by decreasing the efflux ratio of silymarin and by inhibiting silymarin-glucuronidation activity, in which tween 80 played a crucial role. As a result, orally administered Silymarin-SD formulation increased plasma silymarin concentrations and decreased silymarin-glucuronide in rats compared with silymarin alone and silymmarin:D-α-tocopherol polyethylene glycol 1000 succinate (1:1, w/w) formulation. In addition to modulating intestinal first-pass effect, Silymarin-SD formulation showed a significantly higher cumulative dissolution for 120 min compared with that of silymarin from the physical mixture (PM) of the same composition as Silymarin-SD and silymarin alone; the relative BA of silymarin-SD increased to 215% and 589% compared with silymarin-PM and silymarin alone, respectively. This could be attributed to the amorphous status of the Silymarin-SD formulation without chemical interaction with excipients, such as tween 80 and HPC. Moreover, the hepatoprotective effect of Silymarin-SD in acetaminophen-induced acute hepatotoxicity, as estimated from the alanine aminotransferase and aspartate aminotransferase values, was superior to that of silymarin. In conclusion, the increase in the dissolution rate and intestinal permeability of silymarin, and the inhibition of silymarin-glucuronidation by the Silymarin-SD formulation, prepared using tween 80 and HPC, increased its plasma concentration and resulted in a superior hepatoprotective effect compared to silymarin.

A Novel Berberine–Glycyrrhizic Acid Complex Formulation Enhanced the Prevention Effect to Doxorubicin-Induced Cardiotoxicity by Pharmacokinetic Modulation of Berberine in Rats

Developing a new drug delivery system is one of the useful approaches to overcome the limited use of berberine (BBR) to enhance its absorption and bioavailability. We prepared a novel berberine–glycyrrhizic acid (BBR–GL) complex formulation to increase the plasma concentration and bioavailability of BBR by improving BBR solubility and lowering the absorption barrier. The complex formulation with BBR and GL in the ratio 1:1 was developed through the self-assembly process and evaluated in vitro. Compared with BBR and BBR/GL physical mixture, the BBR–GL complex showed different characteristics by SEM, DSC, FT-IR, and PXRD measurement. In pharmacokinetic evaluation, the BBR–GL complex significantly increased the plasma concentration of BBR and the major metabolite berberrubine (BBB), with the AUC of BBR elevated to 4.43-folds, while the complex was safe as BBR. Furthermore, doxorubicin (DOX) was used to induce cardiotoxicity. Hematological study, histopathological examinations, electrocardiography (ECG), cardiac secretion measurement, and biochemical index analysis proved that the model of doxorubicin-induced cardiotoxicity (DIC) was conducted successfully. With the AUC of BBR increasing in the BBR–GL complex and the absorbed complex itself, the BBR–GL complex enhanced prevention effect to DIC and exhibited a significant prevention effect to attenuate heart damage. Our findings demonstrated that a novel BBR-loaded BBR–GL complex formulation could increase BBR plasma concentration. Improvement of BBR bioavailability by the BBR–GL complex could coordinate with GL to attenuate DIC. Concerning the safety of the drug delivery system at present, the BBR–GL complex could be a potential therapeutic formulation for the prevention of cardiac damage in the clinical application of doxorubicin.

Expatiating the Pharmacological and Nanotechnological Aspects of the Alkaloidal Drug Berberine: Current and Future Trends

Traditionally, herbal compounds have been the focus of scientific interest for the last several centuries, and continuous research into their medicinal potential is underway. Berberine (BBR) is an isoquinoline alkaloid extracted from plants that possess a broad array of medicinal properties, including anti-diarrheal, anti-fibrotic, antidiabetic, anti-inflammatory, anti-obesity, antihyperlipidemic, antihypertensive, antiarrhythmic, antidepressant, and anxiolytic effects, and is frequently utilized as a traditional Chinese medicine. BBR promotes metabolisms of glucose and lipids by activating adenosine monophosphate-activated protein kinase, stimulating glycolysis and inhibiting functions of mitochondria; all of these ameliorate type 2 diabetes mellitus. BBR has also been shown to have benefits in congestive heart failure, hypercholesterolemia, atherosclerosis, non-alcoholic fatty liver disease, Alzheimer’s disease, and polycystic ovary syndrome. BBR has been investigated as an interesting pharmacophore with the potential to contribute significantly to the research and development of novel therapeutic medicines for a variety of disorders. Despite its enormous therapeutic promise, the clinical application of this alkaloid was severely limited because of its unpleasant pharmacokinetic characteristics. Poor bioavailability, limited absorption, and poor water solubility are some of the obstacles that restricted its use. Nanotechnology has been suggested as a possible solution to these problems. The present review aims at recent updates on important therapeutic activities of BBR and different types of nanocarriers used for the delivery of BBR in different diseases.

Strategies and Mechanism in Reversing Intestinal Drug Efflux in Oral Drug Delivery

Efflux transporters distributed at the apical side of human intestinal epithelial cells actively transport drugs from the enterocytes to the intestinal lumen, which could lead to extremely poor absorption of drugs by oral administration. Typical intestinal efflux transporters involved in oral drug absorption process mainly include P-glycoprotein (P-gp), multidrug resistance proteins (MRPs) and breast cancer resistance protein (BCRP). Drug efflux is one of the most important factors resulting in poor absorption of oral drugs. Caco-2 monolayer and everted gut sac are sued to accurately measure drug efflux in vitro. To reverse intestinal drug efflux and improve absorption of oral drugs, a great deal of functional amphiphilic excipients and inhibitors with the function of suppressing efflux transporters activity are generalized in this review. In addition, different strategies of reducing intestinal drugs efflux such as silencing transporters and the application of excipients and inhibitors are introduced. Ultimately, various nano-formulations of improving oral drug absorption by inhibiting intestinal drug efflux are discussed. In conclusion, this review has significant reference for overcoming intestinal drug efflux and improving oral drug absorption.

Enhancing Dissolution and Oral Bioavailability of Ursodeoxycholic Acid with a Spray-Dried pH-Modified Extended Release Formulation

Ursodeoxycholate (UDCA) has low oral bioavailability and pH-dependent solubility and permeability. Thus, we developed a pH-modified extended-release formulation of UDCA using Na₂CO₃ as the alkalizing agent and hydroxypropyl methylcellulose (HPMC) as the release-modifying agent. The optimized pH-modified controlled-release UDCA formulation, with the UDCA:HPMC:Na₂CO₃ ratio of 200:600:150 (w/w/w), was prepared using a spray-drying method. Then, the formulation’s solubility, dissolution, and pharmacokinetic properties were characterized. In a pH-modified extended-release formulation of UDCA, the solubility of UDCA was increased to 8 mg/mL with a sustained dissolution for 12 h. Additionally, the spray-dried formulation exhibited amorphous states without molecular interaction among UDCA, Na₂CO₃, and HPMC. Moreover, the plasma UDCA concentration of the formulation maintained a higher UDCA concentration for up to 48 h than that of UDCA itself or the non-extended-release UDCA formulation. Consequently, the formulation significantly increased the AUC compared to UDCA or the non-extended-release UDCA formulation in rats. In conclusion, we have improved UDCA’s solubility and dissolution profile by preparing a pH-modified extended-release formulation with the UDCA:HPMC:Na₂CO₃ ratio of 200:600:150 (w/w/w), which effectively increased the oral bioavailability of UDCA by 251% in rats.

Berberine as a Potential Agent for the Treatment of Colorectal Cancer

Colorectal cancer (CRC) is one of the most commonly diagnosed and deadly malignancies worldwide. The incidence of CRC has been increasing, especially in young people. Although great advances have been made in managing CRC, the prognosis is unfavorable. Numerous studies have shown that berberine (BBR) is a safe and effective agent presenting significant antitumor effects. Nevertheless, the detailed underlying mechanism in treating CRC remains indistinct. In this review, we herein offer beneficial evidence for the utilization of BBR in the management and treatment of CRC, and describe the underlying mechanism(s). The review emphasizes several therapeutic effects of BBR and confirms that BBR could suppress CRC by modulating gene expression, the cell cycle, the inflammatory response, oxidative stress, and several signaling pathways. In addition, BBR also displays antitumor effects in CRC by regulating the gut microbiota and mucosal barrier function. This review emphasizes BBR as a potentially effective and safe drug for CRC therapy.

Synthesis and characterization of berberine-loaded chitosan nanoparticles for the protection of urethane-induced lung cancer

Lung cancer is one of the most common types of malignant tumors of the respiratory system and has the highest rates of incidence and mortality of malignant tumors. This study aimed to synthesize and characterize berberine-loaded chitosan nanoparticles (BBR-COSNPs) and to evaluate their protective effects against urethane-induced lung cancer. Forty male albino mice were divided into four groups, with the first serving as a negative control and the other three groups were injected intraperitoneally with urethane (1 mg/kg b.w) each other day for 1 week then group 2 was served as a positive control, however, groups 3 and 4 were treated orally with a daily dose of BBR or BBR-COSNPs (75 mg/kg b.w) for 10 consecutive weeks. Blood and lung tissue samples are collected for laboratory assay. The BBR-COSNPs were spherical, with an average particle size of 45.56 nm and zeta potential of 39.82 1.82 mV. The in vivo data demonstrated that mice given urethane alone had a significant increase in MDA, NO, NF-κB level, HIF1-α, and COX-2-positive expression in the lung tissue and serum VEGFR2, ALT, AST, urea, and creatinine accompanied with a significant decrease in GSH, SOD, caspase 9 in the lung tissue and serum BAX. Co-treatment with BBR-COSNPs suppressed lung cancer growth and promoted apoptosis by modulating serum BAX and lung caspase 9 gene expressions. In addition, BBR-COSNPs inhibited tumor angiogenesis by reduction in levels of serum VEGFR2 and lung HIF 1 gene expression. It is possible to conclude that BBR-COSNPs can be used in oral administration formulations for lunganticancer therapy.

Development of an Innovative Berberine Food-Grade Formulation with an Ameliorated Absorption: In Vitro Evidence Confirmed by Healthy Human Volunteers Pharmacokinetic Study

Objective

To evaluate in vitro solubility, bioaccessibility, and cytotoxic profile, together with a pharmacokinetic profile by oral administration to healthy volunteers of a novel food-grade berberine formulation (BBR-PP, i.e., berberine Phytosome®).

Results

An in vitro increase of solubility in simulated gastric and intestinal fluids and an improved bioaccessibility at intestinal level along with a lower cytotoxicity with respect to berberine were observed with BBR-PP. The pharmacokinetic profile of the oral administration to healthy volunteers confirmed that berberine Phytosome® significantly ameliorated berberine absorption, in comparison to unformulated berberine, without any observed side effects. The berberine plasma concentrations observed with both doses of BBR-PP were significantly higher than those seen after unformulated berberine administration, starting from 45 min (free berberine) and 30 min (total berberine). Furthermore, BBR-PP improved berberine bioavailability (AUC) was significantly higher, around 10 times on molar basis and with observed dose linearity, compared to the unformulated berberine.

Conclusion

These findings open new perspectives on the use of this healthy berberine formulation in metabolic discomforts.

Nanocomplex of Berberine with C60 Fullerene Is a Potent Suppressor of Lewis Lung Carcinoma Cells Invasion In Vitro and Metastatic Activity In Vivo

Effective targeting of metastasis is considered the main problem in cancer therapy. The development of herbal alkaloid Berberine (Ber)-based anticancer drugs is limited due to Ber’ low effective concentration, poor membrane permeability, and short plasma half-life. To overcome these limitations, we used Ber noncovalently bound to C₆₀ fullerene (C₆₀). The complexation between C₆₀ and Ber molecules was evidenced with computer simulation. The aim of the present study was to estimate the effect of the free Ber and C₆₀-Ber nanocomplex in a low Ber equivalent concentration on Lewis lung carcinoma cells (LLC) invasion potential, expression of epithelial-to-mesenchymal transition (EMT) markers in vitro, and the ability of cancer cells to form distant lung metastases in vivo in a mice model of LLC. It was shown that in contrast to free Ber its nanocomplex with C₆₀ demonstrated significantly higher efficiency to suppress invasion potential, to downregulate the level of EMT-inducing transcription factors SNAI1, ZEB1, and TWIST1, to unblock expression of epithelial marker E-cadherin, and to repress cancer stem cells-like markers. More importantly, a relatively low dose of C₆₀-Ber nanocomplex was able to suppress lung metastasis in vivo. These findings indicated that сomplexation of natural alkaloid Ber with C₆₀ can be used as an additional therapeutic strategy against aggressive lung cancer.

Optimization of Hyaluronate-Based Liposomes to Augment the Oral Delivery and the Bioavailability of Berberine

Various perspectives had been utilized to enhance the poor intestinal permeability and bioavailability of drugs with low water solubility. Berberine (Brb) is a unique molecule that possesses multiple therapeutic activities such as antimicrobial, anti-inflammatory, antioxidant and anti-hyperglycemic effects. To improve Brb permeability and bioavailability, this study presents a newly developed formulation, namely Brb hyaluronate-based liposomes, prepared by using film hydration method and characterized by dynamic light scattering measurements, entrapment efficiency percentage (EE%), transmission electron microscope (TEM), in vitro drug release and physical stability. The bioavailability of the selected formulations was assessed in vivo after oral administration to rats. The results revealed an enhanced effect of hyaluronic acid on the entrapment efficiency, reaching 78.1 ± 0.1% with mean size 520.7 ± 19.9 nm. Sustained release of Brb was recorded up to 24 h in comparison to Brb solution. Physical stability was maintained for three months at refrigeration temperature. Results of pharmacokinetics studies indicated the potential of the liposomal formulation to increase the oral bioavailability of Brb and to accelerate its entry into the bloodstream. The obtained results are accredited to the lipophilic nature of the prepared system, resembling the structural features of bio-membrane, in addition to their small size that enhances intestinal penetration.

Pharmaceutical Formulations with P-Glycoprotein Inhibitory Effect as Promising Approaches for Enhancing Oral Drug Absorption and Bioavailability

P-glycoprotein (P-gp) is crucial in the active transport of various substrates with diverse structures out of cells, resulting in poor intestinal permeation and limited bioavailability following oral administration. P-gp inhibitors, including small molecule drugs, natural constituents, and pharmaceutically inert excipients, have been exploited to overcome P-gp efflux and enhance the oral absorption and bioavailability of many P-gp substrates. The co-administration of small molecule P-gp inhibitors with P-gp substrates can result in drug–drug interactions and increased side effects due to the pharmacological activity of these molecules. On the other hand, pharmaceutically inert excipients, including polymers, surfactants, and lipid-based excipients, are safe, pharmaceutically acceptable, and are not absorbed from the gut. Notably, they can be incorporated in pharmaceutical formulations to enhance drug solubility, absorption, and bioavailability due to the formulation itself and the P-gp inhibitory effects of the excipients. Different formulations with inherent P-gp inhibitory activity have been developed. These include micelles, emulsions, liposomes, solid lipid nanoparticles, polymeric nanoparticles, microspheres, dendrimers, and solid dispersions. They can bypass P-gp by different mechanisms related to their properties. In this review, we briefly introduce P-gp and P-gp inhibitors, and we extensively summarize the current development of oral drug delivery systems that can bypass and inhibit P-gp to improve the oral absorption and bioavailability of P-gp substrates. Since many drugs are limited by P-gp-mediated efflux, this review is helpful for designing suitable formulations of P-gp substrates to enhance their oral absorption and bioavailability.

Improved Hygroscopicity and Bioavailability of Solid Dispersion of Red Ginseng Extract with Silicon Dioxide

This study aims to develop a powder formulation for the Korean red ginseng extract (RGE) and to evaluate its in vitro and in vivo formulation characteristics. The solid dispersion of RGE was prepared with hydrophilic carriers using a freeze-drying method. After conducting the water sorption–desorption isothermogram (relative humidity between 30 and 70% RH), differential scanning calorimetry thermal behavior, dissolution test, and intestinal permeation study, a solid dispersion formulation of RGE and silicon dioxide (RGE-SiO₂) was selected. RGE-SiO₂ formulation increased intestinal permeability of ginsenoside Rb1 (GRb1), GRb2, GRc, and GRd by 1.6-fold in rat jejunal segments as measured by the Ussing chamber system. A 1.6- to 1.8-fold increase in plasma exposure of GRb1, GRb2, GRc, and GRd in rats was observed following oral administration of RGE-SiO₂ (375 mg/kg as RGE). No significant difference was observed in the time to reach maximum concentration (T_max) and half-life in comparison to those in RGE administered rats (375 mg/kg). In conclusion, formulating solid dispersion of RGE with amorphous SiO₂, the powder formulation of RGE was successfully formulated with improved hygroscopicity, increased intestinal permeability, and enhanced oral bioavailability and is therefore suitable for processing solid formulations of RGE product.

Enhanced Bioavailability and Efficacy of Silymarin Solid Dispersion in Rats with Acetaminophen-Induced Hepatotoxicity

We evaluated the bioavailability, liver distribution, and efficacy of silymarin-D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) solid dispersion (silymarin-SD) in rats with acetaminophen-induced hepatotoxicity (APAP) compared with silymarin alone. The solubility of silybin, the major and active component of silymarin, in the silymarin-SD group increased 23-fold compared with the silymarin group. The absorptive permeability of silybin increased by 4.6-fold and its efflux ratio decreased from 5.5 to 0.6 in the presence of TPGS. The results suggested that TPGS functioned as a solubilizing agent and permeation enhancer by inhibiting efflux pump. Thus, silybin concentrations in plasma and liver were increased in the silymarin-SD group and liver distribution increased 3.4-fold after repeated oral administration of silymarin-SD (20 mg/kg as silybin) for five consecutive days compared with that of silymarin alone (20 mg/kg as silybin). Based on higher liver silybin concentrations in the silymarin-SD group, the therapeutic effects of silymarin-SD in hepatotoxic rats were evaluated and compared with silymarin administration only. Elevated alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase levels were significantly decreased by silymarin-SD, silymarin, and TPGS treatments, but these decreases were much higher in silymarin-SD animals than in those treated with silymarin or TPGS. In conclusion, silymarin-SD (20 mg/kg as silybin, three times per day for 5 days) exhibited hepatoprotective properties toward hepatotoxic rats and these properties were superior to silymarin alone, which may be attributed to increased solubility, enhanced intestinal permeability, and increased liver distribution of the silymarin-SD formulation.

Niclosamide-Clay Intercalate Coated with Nonionic Polymer for Enhanced Bioavailability toward COVID-19 Treatment

Niclosamide (NIC), a conventional anthelmintic agent, is emerging as a repurposed drug for COVID-19 treatment. However, the clinical efficacy is very limited due to its low oral bioavailability resulting from its poor aqueous solubility. In the present study, a new hybrid drug delivery system made of NIC, montmorillonite (MMT), and Tween 60 is proposed to overcome this obstacle. At first, NIC molecules were immobilized into the interlayer space of cationic clay, MMT, to form NIC–MMT hybrids, which could enhance the solubility of NIC, and then the polymer surfactant, Tween 60, was further coated on the external surface of NIC–MMT to improve the release rate and the solubility of NIC and eventually the bioavailability under gastrointestinal condition when orally administered. Finally, we have performed an in vivo pharmacokinetic study to compare the oral bioavailability of NIC for the Tween 60-coated NIC–MMT hybrid with Yomesan^®, which is a commercially available NIC. Exceptionally, the Tween 60-coated NIC–MMT hybrid showed higher systemic exposure of NIC than Yomesan^®. Therefore, the present NIC–MMT–Tween 60 hybrid can be a potent NIC drug formulation with enhanced solubility and bioavailability in vivo for treating Covid-19.

Docetaxel/dimethyl-β-cyclodextrin inclusion complexes: preparation, in vitro evaluation and physicochemical characterization

Despite the development in novel drug delivery techniques and synthesis of multifunctional excipients, oral delivery of hydrophobic drug like docetaxel (DTX) is still challenging. The present work investigates the inclusion complexation of DTX, and dimethyl-β-cyclodextrin (DM-β-CD) to improve the solubility, dissolution and permeability of the drug. Amongst the native and modified β-cyclodextrins, DM-β-CD showed the highest solubility of DTX. Solid binary inclusion complex (IC) of DTX with DM-β-CD was prepared by solvent evaporation technique and thoroughly characterized for solubility, dissolution, permeability, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (¹H NMR). The aqueous solubility and in vitro dissolution rate of DTX/DM-β-CD IC were markedly increased by 76.04- and 3.55-fold compared to free DTX powder. The permeability of DTX/DM-β-CD IC showed similar absorptive permeability but decreased efflux from the absorbed DTX, compared to pure DTX. Further, physicochemical studies of IC revealed the change of crystalline state DTX to its amorphous form. Moreover, FT-IR and ¹H NMR results indicate the formation of true inclusion complex between DTX and DM-β-CD at 1:1 molar ratio. Collectively, solid inclusion complexes prepared by spray drying method can be an effective strategy to enhance the biopharmaceutical performance of a highly hydrophobic drug DTX.

Nanotechnology-Based Strategies for Berberine Delivery System in Cancer Treatment: Pulling Strings to Keep Berberine in Power

Cancer is a multifactorial disease characterized by complex molecular landscape and altered cell pathways that results in an abnormal cell growth. Natural compounds are target-specific and pose a limited cytotoxicity; therefore, can aid in the development of new therapeutic interventions for the treatment of this versatile disease. Berberine is a member of the protoberberine alkaloids family, mainly present in the root, stem, and bark of various trees, and has a reputed anticancer activity. Nonetheless, the limited bioavailability and low absorption rate are the two major hindrances following berberine administration as only 0.5% of ingested berberine absorbed in small intestine while this percentage is further decreased to 0.35%, when enter in systemic circulation. Nano-based formulation is believed to be an ideal candidate to increase absorption percentage as at nano scale level, compounds can absorb rapidly in gut. Nanotechnology-based therapeutic approaches have been implemented to overcome such problems, ultimately promoting a higher efficacy in the treatment of a plethora of diseases. This review present and critically discusses the anti-proliferative role of berberine and the nanotechnology-based therapeutic strategies used for the nano-scale delivery of berberine. Finally, the current approaches and promising perspectives of latest delivery of this alkaloid are also critically analyzed and discussed.

Involvement of Organic Anion Transporters in the Pharmacokinetics and Drug Interaction of Rosmarinic Acid

We investigated the involvement of drug transporters in the pharmacokinetics of rosmarinic acid in rats as well as the transporter-mediated drug interaction potential of rosmarinic acid in HEK293 cells overexpressing clinically important solute carrier transporters and also in rats. Intravenously injected rosmarinic acid showed bi-exponential decay and unchanged rosmarinic acid was mainly eliminated by urinary excretion, suggesting the involvement of transporters in its renal excretion. Rosmarinic acid showed organic anion transporter (OAT)1-mediated active transport with a K_m of 26.5 μM and a V_max of 69.0 pmol/min in HEK293 cells overexpressing OAT1, and the plasma concentrations of rosmarinic acid were increased by the co-injection of probenecid because of decreased renal excretion due to OAT1 inhibition. Rosmarinic acid inhibited the transport activities of OAT1, OAT3, organic anion transporting polypeptide (OATP)1B1, and OATP1B3 with IC₅₀ values of 60.6 μM, 1.52 μM, 74.8 μM, and 91.3 μM, respectively, and the inhibitory effect of rosmarinic acid on OAT3 transport activity caused an in vivo pharmacokinetic interaction with furosemide by inhibiting its renal excretion and by increasing its plasma concentration. In conclusion, OAT1 and OAT3 are the major transporters that may regulate the pharmacokinetic properties of rosmarinic acid and may cause herb-drug interactions with rosmarinic acid, although their clinical relevance awaits further evaluation.