Practical gram-scale synthesis of bicyclol metabolites M2 and M3

Bicyclol, an innovative hepatoprotective drug, was approved by the Chinese National Medical Products Administration (NMPA) in 2001 to treat Hepatitis B and drug-induced liver injury. Two active metabolites of bicyclol have been identified as M2 and M3. To evaluate the impact on drug safety and efficacy of possible drug-drug interactions (DDIs) associated with these metabolites, a sufficient quantity of these metabolites is required. Herein, we report a concise novel route for the synthesis of M2 and M3 using the Suzuki-Miyaura coupling as the key step. Furthermore, we complete the gram-scale syntheses of M2 and M3.

Comprehensive review of dibenzocyclooctadiene lignans from the Schisandra genus: anticancer potential, mechanistic insights and future prospects in oncology

Cancer remains one of the leading causes of mortality worldwide. The search for novel and effective anticancer agents has been a significant area of research. Dibenzocyclooctadiene lignans (DBCLS), derived from the Schisandra genus plants like: S. chinensis, S. sphenanthera, S. henryi, S. rubriflora, S. grandiflora, S. propinqua, and S. glabra, have been traditionally used in various medicinal systems and are known for their myriad health benefits, including anticancer properties. This comprehensive review aimed to collate and critically analyse the recent literature on the anticancer properties of DBCLS, focusing on their mechanistic approaches against different cancer types. An exhaustive literature search was performed using databases like PubMed/MedLine, Scopus, Web of Science, Embase, TRIP database and Google Scholar from 1980 to 2023. Peer-reviewed articles that elucidated the mechanistic approach of these lignans on cancer cell lines, in vivo models and preliminary clinical studies were included. Studies were assessed for their experimental designs, cancer types studied, and the mechanistic insights provided. The studies demonstrate that the anticancer effects of DBCLS compounds are primarily driven by their ability to trigger apoptosis, arrest the cell cycle, induce oxidative stress, modulate autophagy, and disrupt essential signaling pathways, notably MAPK, PI3K/Akt, and NF-κB. Additionally, these lignans have been shown to amplify the impact of traditional chemotherapy treatments, suggesting their potential role as supportive adjuncts in cancer therapy. Notably, several studies also emphasise their capacity to target cancer stem cells and mitigate multi-drug resistance specifically. DBCLS from the Schisandra genus have showcased significant potential as anticancer agents. Their multi-targeted mechanistic approach makes them promising candidates for further research, potentially leading to developing of new therapeutic strategies in cancer management.

Investigation on the in vitro metabolism of bicyclol using liver microsomes, hepatocytes and human recombinant cytochrome P450 enzymes

In vitro metabolism of bicyclol was studied using liver microsomes, hepatocytes and human recombinant cytochrome P450 enzymes. Liquid chromatography-benchtop orbitrap mass spectrometry technique was utilized to identify the metabolites.A total of 19 metabolites, including 5 new metabolites (M2, M3, M4, M5 and M16) were tentatively identified. Among these metabolites, M6&M8 (demethylenation), M9&M10 (demethylation) and M19 (glucuronidation) were the major metabolites.In glutathione (GSH)-supplemented liver microsomes, 5 new GSH conjugates were found and tentatively identified. The formation was assumed to be through demethylenation of methylenedioxyphenyl to form catechol derivatives, which further underwent oxidation to form ortho-quinone intermediates, reacting with GSH to form stable adducts.CYP3A4 and 2C19 were demonstrated to be the major enzymes responsible for the bioactivation of bicyclol.This study provided valuable information on the metabolic fate of bicyclol in liver microsomes and hepatocytes, and the bioactivation pathways were reported for the first time, which would be helpful for us to understand the potential drug-drug interactions and the possible side effect of this drug.

Bicyclol Alleviates Streptozotocin-induced Diabetic Cardiomyopathy By Inhibiting Chronic Inflammation And Oxidative Stress

PURPOSE

Diabetic cardiomyopathy (DCM) is a common and severe complication of diabetes. Inflammation and oxidative stress play important roles in DCM development. Bicyclol is a hepatoprotective drug in China that exerts anti-inflammatory effects by inhibiting the MAPK and NF-κB pathways to prevent obesity-induced cardiomyopathy. Our purpose was to explore the effect and mechanism of bicyclol on DCM.

METHODS

A type 1 diabetes mouse model was established using C57BL/6 mice by intraperitoneal injection of STZ. The therapeutic effect of bicyclol was evaluated in both heart tissues of diabetic mice and high concentration of glucose (HG)-stimulated H9c2 cells.

RESULTS

We showed that bicyclol significantly attenuated diabetes-induced cardiac hypertrophy and fibrosis, which is accompanied by the preservation of cardiac function in mice. In addition, bicyclol exhibited anti-inflammatory and anti-oxidative effects both in vitro and in vivo. Furthermore, bicyclol inhibited the hyperglycemia-induced activation of MAPKs and NF-κB pathways, while upregulating the Nrf-2/HO-1 pathway to exhibit protective effects.

CONCLUSION

Our data indicate that bicyclol could be a promising cardioprotective agent in the treatment of DCM.

Effects of bicyclol on hepatic sinusoidal obstruction syndrome induced by Gynura segetum

BACKGROUND

The intake of Gynura segetum, a traditional Chinese medicine, may be induce hepatic sinusoidal obstruction syndrome (HSOS). It has a high mortality rate based on the severity of the disease and the absence of therapeutic effectiveness. Therefore, the current study was designed to investigate the effects of bicyclol on HSOS induced by Gynura segetum and the potential molecular mechanisms.

METHODS

Gynura segetum (30 g/kg) was administered for 4 weeks in the model group, while the bicyclol pretreatment group received bicyclol (200 mg/kg) administration. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), cholesterol (CHO), triglyceride (TG), and liver histological assays were detected to assess HSOS. The gene expressions of cytochrome P450 (CYP450) isozymes were quantified by real-time PCR. Moreover, hepatocellular apoptosis was detected using the terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay, then apoptosis and autophagy-related markers were determined using Western blot.

RESULTS

As a result, bicyclol pretreatment is notably protected against Gynura segetum-induced HSOS, as observed by reducing serum ALT levels, inhibiting the reduction in CHO and TG levels, and alleviating the histopathological changes. Bicyclol pretreatment inhibited the changes in mRNA levels of CYP450 isozymes (including the increase in CYP2a5 and decrease in CYP2b10, 2c29, 2c37, 3a11, and 7b1). In addition, the upregulation of Bcl-2 and the downregulation of LC3-II/LC3-I proteins expression in HSOS were inhibited with bicyclol pretreatment.

CONCLUSION

Bicyclol exerted a protective effect against HSOS induced by Gynura segetum, which could be attributed to the regulated expressions of CYP450 isozymes and alleviated the downregulation of autophagy.

Bicyclol ameliorates advanced liver diseases in murine models via inhibiting the IL-6/STAT3 signaling pathway

Bicyclol, a synthetic hepatoprotective and anti-inflammatory agent approved in China, was widely used to treat various hepatitis accompanied by elevated serum aminotransferases. However, the pharmacological effects and mechanisms of bicyclol on advanced liver diseases, such as fibrosis/cirrhosis and hepatocellular carcinoma (HCC), remain to be explored. Here, we revealed that bicyclol prevents from formatting severe fibrosis, slows the progression of moderate liver fibrosis, accelerates the regression of moderate liver fibrosis, decreases the malignancy of HCC in rat models induced by diethylnitrosamine (DEN), and also blocks steatohepatitis to HCC in mice induced by western diet plus carbon tetrachloride and DEN. The detailed pharmacological mechanism showed that bicyclol alleviates chronic progressive liver diseases by inhibiting the levels of IL-6 and subsequent phosphorylated STAT3. Conclusion: Bicyclol plays significant protective roles in multiply stages of fibrosis/cirrhosis-HCC and nonalcoholic fatty liver disease-related HCC via inhibiting IL-6/STAT3 signaling pathway. Therefore, bicyclol might be a promising therapeutic strategy for treating advanced liver diseases.

Bicyclol ameliorates nonalcoholic fatty liver disease in mice via inhibiting MAPKs and NF-κB signaling pathways

Bicyclol has been approved as an anti-inflammatory, hepatoprotective drug in China to treat various forms of hepatitis. However, the role of bicyclol in non-alcoholic fatty liver disease (NAFLD) is unknown. In this study, NAFLD model was established by feeding mice with high fat diet (HFD) for 16 weeks, and bicyclol (25 and 50 mg/kg) were orally administered for the last 4 weeks. Although bicyclol treatment did not change the body weight of mice, bicyclol administration significantly improved HFD-induced dyslipidemia, NAFLD activity score, hepatic apoptosis, systemic and hepatic inflammation, and liver fibrosis in the mice. Moreover, bicyclol treatment significantly inhibited HFD-induced activation of MAPKs and NF-κB signaling pathways that may mediate the inflammatory responses. Further in vitro studies showed that bicyclol pretreatment markedly ameliorated PA-induced inflammatory responses in human hepatocyte HL-7702 cells and mouse peritoneal macrophages through inhibiting MAPKs and NF-κB signaling pathways. These data indicated that bicyclol may have the potency to treat NAFLD by reducing inflammation.

Therapeutic potential of bicyclol in liver diseases: Lessons from a synthetic drug based on herbal derivative in traditional Chinese medicine

Bicyclol, an innovative chemical drug with proprietary intellectual property rights in China, is based on derivative of traditional Chinese medicine (TCM) Schisandra chinensis (Wuweizi) of North. Mounting data has proved that bicyclol has therapeutic potential in various pathological conditions in liver. In this narrative review, we provide the first summary of pharmacological activities, pharmacokinetic characteristics and toxicity of bicyclol, and discuss future research perspectives. Our results imply that bicyclol has a wide spectrum of pharmacological properties, including anti-viral, anti-inflammatory, immuno-regulatory, anti-oxidative, antisteatotic, anti-fibrotic, antitumor, cell death regulatory effects and modulation of heat shock proteins. Pharmacokinetic studies have indicated that bicyclol is the main substrate of CYP3A/2E1. Additionally, no obvious drug interactions have been found when bicyclol is administered simultaneously with other prescriptions. Furthermore, the results of chronic toxicity have strongly addressed that bicyclol has no noticeable toxic effects on all biochemical indices and pathological examinations of the main organs. In view of good pharmacological actions and safety, bicyclol is anticipated to be a potential candidate for various liver diseases, including acute liver injury, fulminant hepatitis, non-alcoholic fatty liver disease, fibrosis and hepatocellular carcinoma. Further studies are therefore required to delineate its molecular mechanisms and targets to confer this well-designed drug a far greater potency. We hope that bicyclol-based therapeutics for liver diseases might be broadly used in clinical practice worldwide.

Comparison and identification of metabolic profiling of bicyclol in rats, dogs and humans in vitro and in vivo

Bicyclol, a novel hepatoprotective agent, has been widely used to treat chronic viral hepatitis and drug-induced liver injury (DILI). However, its metabolic characteristics remains to be explored, especially in humans. The current study aimed to identify major metabolites and specific metabolizing enzymes involved in bicyclol metabolism in vitro and in vivo using high performance liquid chromatography coupled with Q-Exactive orbitrap mass spectrometry (HPLC-Q-Exactive Orbitrap/MS). After incubation with liver microsomes and oral administration to rats, dogs and humans, a total of nine metabolites of bicyclol were identified including M1 (methyl ester hydrolysate product), M2-M3 (demethylated bicyclol), M4-M5 (demethoxy or dehydroxymethyl bicyclol), M6 (glucuronidated bicyclol) and M7-M9 (glucuronide conjugates of metabolites). Among these metabolites, M2 and M3 were the major phase I metabolites mainly mediated by CYP2C19 and CYP3A4, while M6 was the dominant phase II metabolite primarily catalyzed by UGT2B4. In this study, species-related metabolic difference among rats, dogs and humans were observed. In humans and dogs, M6 (glucuronidated bicyclol) was the most abundant circulating metabolite (higher than the parent drug) in the blood after oral administration, while the parent drug was the highest in rats. M4 and M5 were rats-specific metabolites whereas M1 and M9 were absent in dogs in vivo. The metabolism of bicyclol was demonstrated as demethylation and glucuronidation mediated by multiple drug metabolizing enzymes in different species. Our findings systematically elucidated the metabolic sites and routes of bicyclol in human for the first time, which may be helpful for rational combined application in clinic and further study of metabolites-related efficacy or toxicity.

Compromise or not? A case report of successful treatment of pembrolizumab-induced hepatitis in a patient with non-small cell lung cancer with low-dose methylprednisolone and bicyclol

Pembrolizumab, an anti‐programmed cell death protein 1 (PD‐1) antibody, has been shown to improve survival in patients with non‐small cell lung cancer (NSCLC) with high expression of programmed death‐ligand 1 (PD‐L1). Corticosteroids are the mainstay for most high‐grade immune‐related adverse events (irAEs) such as pembrolizumab‐induced hepatitis. However, the dose and duration of corticosteroid therapy are not well defined. The objective of this case report was to describe a new treatment pattern for severe immune checkpoint inhibitor‐associated hepatitis. Here, we report the case of a patient with metastatic lung adenocarcinoma who developed grade 3 immunotherapy‐induced hepatitis after the first cycle of pembrolizumab. Alanine aminotransferase (ALT) levels peaked at 233 U/L. Hepatitis was alleviated after the administration of methylprednisolone. Therefore, we retreated the patient with pembrolizumab. However, aminotransferase levels increased again after the initiation of low‐dose methylprednisolone or the reuse of pembrolizumab. Finally, hepatitis was controlled with low‐dose methylprednisolone plus bicyclol, a Chinese hepatoprotective agent. Although the patient had been on low‐dose methylprednisolone therapy for about six months, he showed a prompt response. During this period, we also found a dramatic decrease in the neutrophil‐lymphocyte ratio (NLR), senescent T cells (CD8⁺CD28⁻CD57⁺), and myeloid‐derived suppressor cells (MDSCs) in the peripheral blood of the patient. To our knowledge, this is the first case report of successful management of grade 3 pembrolizumab‐induced hepatitis with a combination of low‐dose corticosteroids and bicyclol. The durable clinical response and changes in blood biomarkers indicate that low doses of corticosteroids do not compromise the efficacy of immune checkpoint inhibitors (ICIs). Therefore, this case may provide a new treatment pattern for severe immunotherapy‐induced hepatitis.

Histological improvement in chronic hepatitis B patients treated with bicyclol: real world experience

Background

Bicyclol, the most commonly-used liver hepatoprotective drug in China, is often selected to control disease progression in CHB patients who refuse anti-viral treatment. However, data on histological changes after bicyclol treatment in these patients are scarce. Therefore, this study has been conducted to find out whether bicyclol has good benefits of histological improvement in CHB patients who refuse anti-viral agents.

Methods

The demographic, clinical and pathological data were collected from CHB patients who received bicyclol from January 2010 to June 2016. Improvement in liver inflammation or fibrosis is defined as at least one-grade or one-stage decrease as measured by the Scheuer scoring system. Thirty patients treated with ETV for 48 weeks were chosen as a control group to compare the histological improvement between bicyclol and entecavir (ETV) after 48-week treatment.

Results

A total of 123 patients with CHB treated with bicyclol were included in this study. Paired liver biopsies were performed in 70 patients. Inter-biopsy interval was 17.44 ± 8.90 months (12–60 months). As shown by facts, 41.4% patients achieved liver inflammation improvement, while only 10.0% patients showed liver inflammation progression after bicyclol treatment. In regarding to liver fibrosis, as shown by facts, 28.6% patients achieved fibrosis improvement. More importantly, It was found that the proportions of patients with liver inflammation and fibrosis improvement were both not significantly lower than those in ETV group (53.3% vs 63.3 and 36.7% vs 43.4%). Most of patients (82.4%) with elevated baseline ALT became normal after bicyclol treatment. More importantly, as shown by the multi-variate analysis, the treatment course of bicyclol was an independent factor for liver inflammation improvement. With the HBeAg status adjusted, ALT and HBV-DNA quantity, the odds ratio (95% confidence interval) of patients with ≥48-week treatment was 5.756 (1.893,17.500) when compared with patients via < 48-week treatment.

Conclusion

Bicyclol can improve liver inflammation and the ALT normalization rate of CHB patients, especially when the treatment course is prolonged. This has confirmed that bicyclol could control hepatitis activity, which might be a good choice for CHB patients who refuse anti-viral treatments.

[Interventional effect of bicyclol on isoniazid-induced liver injury in rats and the expression of glucose-regulated protein 78, and growth arrest and DNA-damage-inducible gene 153]

Objective: To investigate the interventional effect of bicyclol on isoniazid-induced liver injury in rats and the expression of endoplasmic reticulum stress (ERS) protein, glucose regulatory protein 78 (GRP78), and growth arrest and DNA-damage-inducible gene 153(CHOP). Methods: Eighty Wistar rats were randomly divided into control group (8 rats) and model group (72 rats). After 10 days of intragastric administration of isoniazid, the model group rats were randomly divided into treatment group (A), natural recovery group (B), etiological persistence group (C) and etiological persistence plus treatment group (D). Sixteen rats from each group were sacrificed after 1 and 2 weeks of intervention with different methods. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were detected. Liver pathological morphology was observed. Apoptotic cells were detected by TUNEL assay. ERS protein expression was detected by Western blot. A t-test or randomized block analysis of variance, K-S test and Levene's test were used to analyze the normality and homogeneity of variance. Kruskal-Wallis rank sum test was used for data that did not suit the conditions of t-test and variance analysis. Results: ALT and AST were elevated in the model group, and liver pathological examination showed liver tissue damage. Apoptotic index was higher than control group (7.13% ± 1.55% vs. 0.75% ± 0.71%, Z = -3.411, P < 0.01), and the expression value of ERS protein in model group was significantly higher than control group (GRP78: 1.16 ± 0.30 vs. 0.23 ± 0.05, t = -6.008, P < 0.01; CHOP: 0.98±0.23 vs. 0.20 ± 0.10, t = -6.378, P < 0.01). Serum enzymes, apoptotic index and ERS protein expressions of rats were decreased after treatment with bicyclol, and the pathological damage was eased. Rats in natural recovery group recovered less than the treatment group. Conclusion: Isoniazid-induced liver injury is associated to ERS-related excessive apoptosis and the therapeutic effect of bicyclol on drug-induced liver injury may minimize ERS-induced apoptosis.

Up-regulation of glycolipid transfer protein by bicyclol causes spontaneous restriction of hepatitis C virus replication

Bicyclol is a synthetic drug for hepatoprotection in clinic since 2004. Preliminary clinical observations suggest that bicyclol might be active against hepatitis C virus (HCV) with unknown mechanism. Here, we showed that bicyclol significantly inhibited HCV replication in vitro and in hepatitis C patients. Using bicyclol as a probe, we identified glycolipid transfer protein (GLTP) to be a novel restrictive factor for HCV replication. The GLTP preferentially bound host vesicle-associated membrane protein-associated protein-A (VAP-A) in competition with the HCV NS5A, causing an interruption of the complex formation between VAP-A and HCV NS5A. As the formation of VAP-A/NS5A complex is essential for viral RNA replication, up-regulation of GLTP by bicyclol reduced the level of VAP-A/NS5A complex and thus inhibited HCV replication. Bicyclol also exhibited an inhibition on HCV variants resistant to direct-acting antiviral agents (DAAs) with an efficacy identical to that on wild type HCV. In combination with bicyclol, DAAs inhibited HCV replication in a synergistic fashion. GLTP appears to be a newly discovered host restrictive factor for HCV replication, Up-regulation of GLTP causes spontaneous restriction of HCV replication.

Bicyclol exerts an anti-tumor effect via ROS-mediated endoplasmic reticulum stress in human renal cell carcinoma cells

Renal cell carcinoma (RCC) is the most common subtype of kidney cancer. Currently, there is a lack of efficient treatment for RCC. Bicyclol, an anti-hepatitis drug, has been demonstrated to possess anti-tumor properties. However, the effect of bicyclol in RCC remains elusive. Therefore, the aim of this study is to investigate the biological effects of bicyclol on RCC and the underlying mechanisms. The data from this study indicated that bicyclol markedly induced cell apoptosis and cell cycle arrest and increased the production of reactive oxygen species (ROS) in RCC cells. Moreover, bicyclol induced ER stress in a ROS-dependent manner, since the ROS scavenger NAC could block this effect. Taken together, the results of this study provide evidence that bicyclol may serve as a potential therapeutic agent for the treatment of human RCC.

Effect of Bicyclol Tablets on Drug Induced Liver Injuries after Kidney Transplantation

Liver injury is one of the most common complications in patients after kidney transplantation. Bicyclol tablets possess obvious anti-inflammatory and liver-protective functions. This study aimed to explore the clinical effect of preventive application of Bicyclol on drug induced liver injuries at an early stage after kidney transplantation.

A total of 1600 patients who accepted kidney transplantations at our hospital from January 2009 to May 2015 were enrolled in this study, and divided into the prevention group (Bicyclol) and the control group (no hepatic protectors) based on whether or not hepatic protectors were regularly administered after the operation. The occurrence of liver injuries at an early stage after the operation and their influencing factors were analyzed.

Total of 745 cases were included in the final analysis of which 82 developed liver injuries post-operation, with 22 in the prevention group (4.82%) as compared to 60 in the control group (20.76%) (P= 0.001). As compared to the control group, OR (95% CI) of the prevention group was 0.197 (0.116, 0.334) after revising HBsAg status, age and maintenance immunosuppression.

Prophylactic application of Bicyclol as liver-protective treatment was a protective factor against drug induced liver injuries at an early stage after kidney transplantation.

Hepatitis B patients exhibiting mild alanine aminotransferase elevation: A comparative analysis of treatment with and without Bicyclol tablets

The aim of the present study was to analyze the medicinal effect of Bicyclol tablets on patients with chronic hepatitis B (CHB) and concomitant mild alanine aminotransferase (ALT) elevation (40-80 IU/l). A retrospective cohort study, which included patients from the hospital information system (HIS; established by the Chinese Academy of Medical Sciences) viral hepatitis database comprised of 18 third-grade class A hospitals in China, was performed. Patients were divided into an exposed group (administered with Bicyclol tablets) and a non-exposed group (no administration of Bicyclol tablets). The CHB patients that exhibited mild ALT elevation provided the curative effect analysis data set, and the patients with viral hepatitis who underwent more than two creatinine/hemoglobin/leucocyte examinations served as the safety analysis data set. The factors influencing ALT normalization rate were analyzed and the safety of Bicyclol tablets was assessed. In total, 82 pairs of patients were included in the curative effect analysis, and single factor analysis revealed that the ALT normalization rate of the exposed group was statistically significantly higher than that of the non-exposed group (P=0.040) for patients with mild ALT elevation. After adjusting for patient age, gender, baseline ALT levels, state of illness upon admission, pattern of hospitalization, hospitalization days and drug combination, the odds ratio (95% confidence interval) of the ALT normalization rate of the exposed group was 2.156 (1.103-4.215) when compared with the non-exposed group. During treatment, the occurrence rates of creatinine/hemoglobin/leucocyte level abnormalities of the exposed group, which were included in the safety analysis were statistically significantly lower than those of the non-exposed group (P<0.05). These findings indicate that Bicyclol tablets improve the ALT normalization rate of CHB patients exhibiting mild ALT elevation.

Bicyclol induces cell cycle arrest and autophagy in HepG2 human hepatocellular carcinoma cells through the PI3K/AKT and Ras/Raf/MEK/ERK pathways

Background

Bicyclol, a novel synthetic antihepatitis drug, is widely known to protect against liver injury. However, few reports have focused on the possible effect of bicyclol on anti-proliferation and autophagy induction in cancer cells, particularly hepatocellular carcinoma cells.

Methods

In this study, we investigated the antitumor efficacy of Bicyclol in HepG2 cells and the mechanism of cell growth inhibition. Cell proliferation was analyzed by MTT assay, and the cell cycle and apoptosis were assessed by flow cytometry. And we transfected the cells with the GFP-RFP-LC3 vector to detect the autophagy flux in the cells. Mechanisms of bicyclol-induced cell growth inhibition were probed by western blot analysis.

Results

Bicyclol effectively inhibited HepG2 cell proliferation in a dose- and time-dependent manner. In addition, we found that bicyclol inhibited cell cycle progression at G1 phase and induced autophagy in HepG2 cells, which implied that the significant decrease in cell proliferation was mainly induced by autophagy and inhibition of cell proliferation. Furthermore, western blot showed that bicyclol inhibited phosphorylation of Akt and ERK, down-regulated the expressions of cyclin D1, cyclin E2, CDK2, CDK4, p-Rb and p-mTOR. Moreover, AKT or ERK knockdown by siRNA enhanced bicyclol-induced autophagy and inhibition of cell proliferation.

Conclusion

These results suggest that bicyclol has potent anti-proliferative activity against malignant human hepatoma cells via modulation of the PI3K/AKT pathway and the Ras/Raf/MEK/ERK pathway, and indicate that bicyclol is a potential liver cancer drug worthy of further research and development.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2767-2) contains supplementary material, which is available to authorized users.

Bicyclol promotes toll-like 2 receptor recruiting inosine 5'-monophosphate dehydrogenase II to exert its anti-inflammatory effect

The aim was to investigate potential targets and anti-inflammatory mechanisms of bicyclol, which has been extensively used in clinic for decades in China. Tar-Fis-Dock, virtual molecular docking system, showed that inosine 5'-monophosphate dehydrogenase II (IMPDH II) has the highest probability of binding to bicyclol. To investigate the possible role of IMPDH II in mechanisms of bicyclol, recombinant enzyme models, mice splenic lymphocytes, and human lymphocytes were used. Bicyclol (1-5 μM) significantly inhibited the proliferation of mice splenic lymphocytes stimulated by concanavalin A (conA). However, bicyclol did not show inhibitory effects on proliferation of human peripheral blood mononuclear cells (hPBMC) induced by phytohemagglutinin (PHA). IMPDH II enzyme kinetic model showed that bicyclol only had a slight regulatory effect on IMPDH II enzyme activity. These results revealed that bicyclol may be not a conventional inhibitor of IMPDH II. Further studies showed that bicyclol could promote recruitment of IMPDH II by active toll-like 2 receptor (TLR2) complex. Such effects lead to the reduction of nuclear factor κB (NF-κB) expression, increase in I-κB expression, and decrease in cytokine release, including tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β). It may be a new mechanism of bicyclol for its anti-inflammatory effect.

Application of physiologically based pharmacokinetic modeling in the prediction of pharmacokinetics of bicyclol controlled-release formulation in human

Physiologically based pharmacokinetic (PBPK) modeling can assist in formulation development. Bicyclol is a novel anti-hepatitis drug. A bilayer osmotic pump table of bicyclol is being developed. PBPK models for bicyclol immediate-release (IR) and controlled-release (CR) tablets in beagle dog, as well as PBPK model for IR tablets in human were constructed. These models incorporated physicochemical properties and in vitro preclinical data. Parameter sensitivity analysis was performed for the effects of solubility and dissolution on pharmacokinetic (PK) parameters. Models were refined by comparing simulated results to experimental measurements. Furthermore, the clinical PK for bicyclol CR tablets was predicted using the in vivo dissolution profile by deconvolution of the mean PK profile of CR tablets in dogs. In summary, the present study described a strategy employing PBPK models to evaluate the effects of formulation factors on PK profiles and predict the performance of bicyclol CR tablets in human.

Protective effect of bicyclol against bile duct ligation-induced hepatic fibrosis in rats

AIM: To evaluate the protective effect of bicyclol against bile duct ligation (BDL)-induced hepatic fibrosis in rats.

METHODS: Sprague-Dawley male rats underwent BDL and sham-operated animals were used as healthy controls. The BDL rats were divided into two groups which received sterilized PBS or bicyclol (100 mg/kg per day) orally for two consecutive weeks. Serum, urine and bile were collected for biochemical determinations. Liver tissues were collected for histological analysis and a whole genome oligonucleotide microarray assay. Reverse transcription-polymerase chain reaction and Western blotting were used to verify the expression of liver fibrosis-related genes.

RESULTS: Treatment with bicyclol significantly reduced liver fibrosis and bile duct proliferation after BDL. The levels of alanine aminotransferase (127.7 ± 72.3 vs 230.4 ± 69.6, P < 0.05) and aspartate aminotransferase (696.8 ± 232.6 vs 1032.6 ± 165.8, P < 0.05) were also decreased by treatment with bicyclol in comparison to PBS. The expression changes of 45 fibrogenic genes and several fibrogenesis-related pathways were reversed by bicyclol in the microarray assay. Bicyclol significantly reduced liver mRNA and/or protein expression levels of collagen 1a1, matrix metalloproteinase 2, tumor necrosis factor, tissue inhibitors of metalloproteinases 2, transforming growth factor-β1 and α-smooth muscle actin.

CONCLUSION: Bicyclol significantly attenuates BDL-induced liver fibrosis by reversing fibrogenic gene expression. These findings suggest that bicyclol might be an effective anti-fibrotic drug for the treatment of cholestatic liver disease.

Role of bicyclol in preventing chemotherapeutic agent-induced liver injury in patients over 60 years of age with cancer

OBJECTIVE

To evaluate the efficacy of bicyclol in preventing chemotherapy-induced liver damage.

METHODS

Patients ≥60 years of age with cancer were equally randomized into control (chemotherapy alone) or prophylactic (chemotherapy supplemented with 75 mg bicyclol, oral, daily) groups. Liver function indices were assessed immediately before treatment, during each therapy cycle and following treatment.

RESULTS

Of 306 patients enrolled, 300 patiets completed the study (n = 147 and n = 153; prophylactic and control groups, respectively). Incidence of grade I-IV elevation of serum transaminase and/or bilirubin was significantly lower in the prophylactic group (17.1%) compared with the control group (47.1%). Incidence of grade II-IV hepatic injury was also significantly lower in the prophylactic group (0.7%) than in the control group (12.4%).

CONCLUSIONS

Prophylactic bicyclol (75 mg daily) could significantly reduce the incidence and degree of chemotherapeutic agent-induced liver damage in elderly patients with cancer. Further studies are recommended with larger sample sizes and long-term follow up.

Spectroscopic study on the interaction of Trypsin with Bicyclol and analogs

The interactions between Trypsin and Bicyclol or analogs (Bifendate, I, II and III) were investigated by spectrophotometric methods. It was found that Bicyclol or analogs had strong ability to quench the intrinsic fluorescence of Trypsin by a static quenching procedure. The binding constants were obtained at three temperatures. The thermodynamics parameters reveal that the hydrophobic and electrostatic interactions play an important role in the interaction. Results showed that the microenvironments of tryptophan residue of Trypsin were disturbed by the analogs. Results indicated that Bifendate was the strongest quencher among five compounds.

Bicyclol upregulates transcription factor Nrf2, HO-1 expression and protects rat brains against focal ischemia

Oxidative damage plays a detrimental role in the pathophysiology of cerebral ischemia and may represent a therapeutic target. The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) controls the coordinated expression of the important antioxidant and detoxification genes through a promotor sequence termed the antioxidant response element. Bicyclol has been proved to elicit a variety of biological effects through its antioxidant and anti-inflammatory properties. But the underlying mechanisms are poorly understood. In this study, the role of bicyclol in cerebral ischemia and its potential mechanism were investigated.

METHODS

Male Sprague-Dawley rats were randomly assigned to five groups: MCAO (middle cerebral artery occlusion), Vehicle (MCAO+0.5% sodium carboxymethylcellulose), By-L (Vehicle+bicyclol 50mg/kg), By-H (Vehicle+bicyclol 100mg/kg) and Sham operated groups. Bicyclol was administered intragastrically once a day for 3 consecutive days; after 1h of bicyclol pretreatment on the third day, rat ischemic stroke was induced by MCAO. Neurological deficit, infarct volume, and brain edema were detected at 24h after stroke. Western blot and RT-qPCR were used to measure the expression of Nrf2, HO-1 and SOD1. MDA was detected by the spectrophotometer.

RESULTS

Compared with MCAO group, By-H group significantly ameliorated neurological deficit, lessened the infarct volume and brain edema, increased the expression of Nrf2, HO-1 and SOD1 (P<0.05), and decreased the content of MDA (P<0.05).

CONCLUSIONS

Bicyclol protected the rat brain from ischemic damage caused by MCAO, and this effect may be through the upregulation of the transcription factor Nrf2 expression.

Neuroprotective effect of bicyclol in rat ischemic stroke: down-regulates TLR4, TLR9, TRAF6, NF-κB, MMP-9 and up-regulates claudin-5 expression

BACKGROUND

Inflammatory damage aggravates the cerebral ischemic pathological process and may pave a new way for treatment. Bicyclol has been proved to elicit a series of biologic effects through its anti-inflammatory property in treating hepatitis and hepatic ischemic/reperfusion injury. Whether this protective effect applies to cerebral ischemic injury, we therefore investigated the potential neuroprotective role of bicyclol and the underlying mechanisms.

METHODS

Male Sprague-Dawley rats were randomly assigned to five groups: permanent middle cerebral artery occlusion (pMCAO), Vehicle (pMCAO+0.5% sodium carboxymethylcellulose), By-L (Vehicle+bicyclol 50 mg/kg), By-H (Vehicle+bicyclol 100 mg/kg) and Sham operated group. Bicyclol was administered intragastrically once a day for 3 days, after 1h of bicyclol pretreatment on the third day; rat brain ischemia was induced by pMCAO. Neurological deficit, infarct volume, and brain edema were measured at 24 h after stroke. Immunohistochemistry, Western blot and real-time quantitative PCR were used to detect the expression of TLR4, TLR9, TRAF6, NF-κB and MMP-9, claudin-5.

RESULTS

Compared with pMCAO group, bicyclol significantly ameliorated neurological deficit, decreased infarct volume and edema, and down-regulated the expression of TLR4, TLR9, TRAF6, NF-κB and MMP-9 (P<0.05). Meanwhile, the expression of claudin-5 was increased (P<0.05).

CONCLUSIONS

Bicyclol has neuroprotective effect on cerebral ischemia, and this protection may be through down-regulating TLR4, TLR9, TRAF6, NF-κB, MMP-9 and up-regulating claudin-5 expression.

A randomized, multi-central, controlled study of patients with hepatitis B e antigen-positive chronic hepatitis B treated by adefovir dipivoxil or adefovir dipivoxil plus bicyclol

Objective

To evaluate the efficacy and safety profiles of patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) treated with adefovir dipivoxil (ADV) or ADV plus bicyclol, and to optimize the treatment strategy for CHB patients.

Patients and methods

A total of 250 patients with HBeAg-positive CHB were randomized to ADV plus bicyclol combination group and ADV monotherapy group. The patients in the ADV plus bicyclol combination therapy group (n = 125) received ADV 10 mg orally q.d. and bicyclol 25 mg orally t.i.d. for 48 weeks, and those in the ADV monotherapy group (n = 125) were administered ADV 10 mg orally q.d. alone for 48 weeks. The serum aminotransferases (ALT/AST), HBV DNA, HBeAg/HBeAb, and liver biopsy were conducted before and after therapy.

Results

The serum aminotransferase levels were decreased significantly in both groups. The serum aminotransferase level in ADV plus bicyclol combination therapy group decreased greater than that in ADV monotherapy group (P < 0.01). The virological response rate in ADV plus bicyclol combination therapy group was not significantly different from that in ADV monotherapy group (P > 0.05). After treatment for 48 weeks, the Knodell necroinflammatory score of the two groups were all alleviated significantly, and the Knodell score in the combination group was significantly lower than that in the ADV monotherapy group (P < 0.05). There were no remarkable adverse events probably related to the drug in this study.

Conclusion

Adefovir dipivoxil plus bicyclol combination therapy is a safe and superior treatment regimen for patients with HBeAg-positive CHB when compared with ADV monotherapy.

Effect of bicyclol on the expression of hepatic immediate early genes, TGF-β1, TIMP1 and collagen in liver tissues of mice infected with Schistosoma japonicum

AIM: To study the therapeutic effect of bicyclol on schistosome-infected mice with liver fibrosis and its mechanism.

METHODS: Eighty mice were divided into four groups. Mice in the low-dose, high-dose and experimental control groups were infected with Schistosoma japonicum. After eight weeks, the low-dose and high-dose groups were treated with bicyclol at 60 mg (kg· d) and 120 mg (kg· d), respectively, for 8 weeks. The experimental control group received no treatment. The fourth group was a normal control group. HE staining, RT-PCR and immunohistochemistry were used to observe the pathological changes in liver tissues of mice, the expression levels of hepatic c-fos and c-jun mRNAs, and the levels of hepatic transforming growth factor β1 (TGF-β1), tissue inhibitor of metalloproteinase 1 (TIMP1), and types I and III collagen, before and after treatment.

RESULTS: Bicyclol treatment at a high dosage significantly relieved the degree of hepatic fibrosis compared with the experimental control group. The mRNA expression levels of c-fos and c-jun in liver tissue were significantly reduced in the high-dose group compared with the experimental control and low-dose groups (c-fos mRNA: 0.6511 ± 0.0551 vs 0.7844 ± 0.0852, 0.8072 ± 0.0923; c-jun mRNA: 0.6803 ± 0.0712 vs 0.7982 ± 0.0902, 0.8289 ± 0.094). The levels of hepatic TGF-β1, TIMP1 and types I and III collagen in the high-dose bicyclol treated group (integral light density: 0.1815 ± 0.0231, 0.2324 ± 0.0536, 0.1811 ± 0.0514, 0.1543 ± 0.0603) were significantly lower than those in the experimental control group (0.2139 ± 0.0134, 0.2648 ± 0.0361, 0.2140 ± 0.0271, 0.1862 ± 0.0217), but were still higher than those in the normal control group.

CONCLUSION: The effect of bicyclol on liver fibrosis due to Schistosoma japonicum infection depend on its dosage. The anti-fibrotic effect of high-dose bicyclol treatment may be due to its inhibition on the expression of immediate early genes, which may lead to reduced synthesis of TGFβ and TIMP1.

Toxicity of novel anti-hepatitis drug bicyclol: A preclinical study

AIM: To study the toxicity of bicyclol to animals.

METHODS: Acute toxicity test was performed in Kunming strain mice that were orally given bicyclol at the doses of 3 and 5 g/kg body weight, respectively. Wistar rats were orally administered bicyclol at a dose of 5 g/kg body weight. Death and clinical symptoms of animals were recorded within 7 d. Sub-acute toxicity test was carried out in rats that were treated with various doses of bicyclol (150, 300, 600 mg/kg) once daily for 14 d. Animal behaviors, blood biochemical markers, blood and urine pictures were examined. Chronic toxicity test was conducted in 80 Wistar rats of both sexes. The animals were orally administered with various doses of bicyclol [150, 300, 600 mg/kg, 100-400 folds corresponding to the proposed therapeutic dose (1.5 mg/(kg·d)) of bicyclol for patients] once daily for 6 mo except for Sunday. The control group was given the same volume of 0.2% sodium carboxyl methylcellulose (Na-CMC). Twenty-one beagle dogs received bicyclol (25, 75, 225 mg/kg, 16.6, 50, 150 folds corresponding to the proposed therapeutic dose of bicyclol for patients) once a day for 6 mo except for Sunday. The body weight, food intake, urine and feces, blood picture, blood biochemical markers, and pathological examination of main organs were determined. Mutagenicity and teratogenicity were determined. Mutagenicity assay included Ames’s test, chromosome aberration test in CHL cells and micronucleus test in mice. For the teratogenicity assay, pregnant Wistar rats weighing 200-250 g were treated with 0.2, 1.0 g/kg bicyclol once daily from the 7th d of gestation for 10 d.

RESULTS: The oral LD₅₀ of bicyclol was over 5 g/kg in mice and rats. No noticeable alterations in subacute and chronic toxicity of rats and dogs were demonstrated. No mutagenicity and teratogenicity of bicyclol were found.

CONCLUSION: Bicyclol has no detectable chronic toxicity as well as mutagenicity and teratogenicity in animals.