Health risk assessment for human mercury exposure from Cinnabaris-containing Baizi Yangxin Pills in healthy volunteers Po administration.

BACKGROUND: Cinnabaris (α-HgS), a mineral traditional Chinese material medica, has been used in combination with other herbs manifesting some definite therapeutic effects for thousands of years. But the currently reported mercury poisoning incidents raised the doubts about the safety of Cinnabaris-containing traditional Chinese medicines (TCMs). Baizi Yangxin Pills (BZYXP) is a Cinnabaris-containing TCM widely used in clinical practice. This study evaluated the health risk of mercury exposure from BZYXP in healthy volunteers based on the total mercury and mercury species analysis of blood and urine after single and multiple doses of BZYXP. METHODS: Blood pharmacokinetics and urinary excretion studies of mercury were compared between single (9 g, once daily) and multiple doses (9 g, twice daily, continued for 7 days) of BZYXP. The whole blood and urine samples were collected at the specific points or periods after the administration of BZYXP. The total mercury and mercury species in blood and urine samples were determined by cold vapor-atomic fluorescence spectrometry (CV-AFS) and HPLC-CV-AFS, respectively. RESULTS: The mercury was excreted slowly and accumulated obviously after continuous exposure of BZYXP. Moreover, the well-known neurotoxin methylmercury (MeHg) was detected in blood samples after 7 days' administration of BZYXP. In the urine samples, only Hg(II) was detected. Therefore, long-term use of BZYXP will cause mercury poisoning due to mercury's high accumulative properties and MeHg formation. CONCLUSION: Cinnabaris-containing TCMs such as BZYXP should be restricted to cases in which alternatives are available, and the blood mercury species profile should be monitored during the long-term clinical medication.

Lymphatic vessel: origin, heterogeneity, biological functions, and therapeutic targets.

Lymphatic vessels, comprising the secondary circulatory system in human body, play a multifaceted role in maintaining homeostasis among various tissues and organs. They are tasked with a serious of responsibilities, including the regulation of lymph absorption and transport, the orchestration of immune surveillance and responses. Lymphatic vessel development undergoes a series of sophisticated regulatory signaling pathways governing heterogeneous-origin cell populations stepwise to assemble into the highly specialized lymphatic vessel networks. Lymphangiogenesis, as defined by new lymphatic vessels sprouting from preexisting lymphatic vessels/embryonic veins, is the main developmental mechanism underlying the formation and expansion of lymphatic vessel networks in an embryo. However, abnormal lymphangiogenesis could be observed in many pathological conditions and has a close relationship with the development and progression of various diseases. Mechanistic studies have revealed a set of lymphangiogenic factors and cascades that may serve as the potential targets for regulating abnormal lymphangiogenesis, to further modulate the progression of diseases. Actually, an increasing number of clinical trials have demonstrated the promising interventions and showed the feasibility of currently available treatments for future clinical translation. Targeting lymphangiogenic promoters or inhibitors not only directly regulates abnormal lymphangiogenesis, but improves the efficacy of diverse treatments. In conclusion, we present a comprehensive overview of lymphatic vessel development and physiological functions, and describe the critical involvement of abnormal lymphangiogenesis in multiple diseases. Moreover, we summarize the targeting therapeutic values of abnormal lymphangiogenesis, providing novel perspectives for treatment strategy of multiple human diseases.

AChE activity self-breathing control mechanisms regulated by H2Sn and GSH: Persulfidation and glutathionylation on sulfhydryl after disulfide bonds cleavage.

Hydrogen sulfide (H2S), or dihydrogen sulfane (H2Sn), acts as a signal molecule through the beneficial mechanism of persulfidation, known as the post-translational transformation of cysteine residues to persulfides. We previously reported that Glutathione (GSH) could regulate enzyme activity through S-desulfurization or glutathionylation of residues to generate protein-SG or protein-SSG, releasing H2S. However, little is known about the mechanisms by which H2Sn and GSH affect the disulfide bonds. In this study, we provide direct evidences that H2Sn and GSH modify the sulfhydryl group on Cys272, which forms disulfide bonds in acetylcholinesterase (AChE), to generate Cys-SSH and Cys-SSG, respectively. Glutathionylation of disulfide is a two-step reaction based on nucleophilic substitution, in which the first CS bond is broken, then the SS bond is broken to release H2S. H2Sn and GSH controlled self-breathing motion in enzyme catalysis by disconnecting specific disulfide bonds and modifying cysteine residues, thereby regulating AChE activity. Here, we elucidated H2Sn and GSH mechanisms on disulfide in the AChE system and proposed a self-breathing control theory induced by H2Sn and GSH. These theoretical findings shed light on the biological functions of H2Sn and GSH on sulfhydryl and disulfide bonds and enrich the theory of enzyme activity regulation.

Evaluation of pharmacological and pharmacokinetic herb-drug interaction between irinotecan hydrochloride injection and Kangai injection in colorectal tumor-bearing mice and healthy rats.

Introduction: Kangai (KA) injection, a Chinese herbal injection, is often used in combination with irinotecan (CPT-11) to enhance the effectiveness of anti-colorectal cancer treatment and alleviate side effects. However, the combined administration of this herb-drug pair remains controversial due to limited pre-clinical evidence and safety concerns. This study aimed to determine the pre-clinical herb-drug interactions between CPT-11 and KA injection to provide a reference for their clinical co-administration. Methods: In the pharmacological study, BALB/c mice with CT26 colorectal tumors were divided into four groups and treated with vehicle alone (0.9% saline), CPT-11 injection (100 mg/kg), KA injection (10 mL/kg), or a combination of CPT-11 and KA injection, respectively. The tumor volume of mice was monitored daily to evaluate the therapeutic effect. Daily body weight, survival rate, hematopoietic toxicity, immune organ indices, and gut toxicity were analyzed to study the adverse effects. Healthy Sprague-Dawley rats in the pharmacokinetic study were administered KA injection only (4 mL/kg), or a combination of CPT-11 injection (20 mg/kg) and KA injection, respectively. Six key components of KA injection (oxymatrine, matrine, ginsenoside Rb1, Rg1, Re, and astragaloside IV) in rat plasma samples collected within 24 h after administration were determined by LC-MS/MS. Results: The pharmacological study indicated that KA injection has the potential to enhance the anti-colorectal cancer efficacy of CPT-11 injection and alleviate the severe weight loss induced by CPT-11 injection in tumor-bearing mice. The pharmacokinetic study revealed that co-administration resulted in inhibition of oxymatrine metabolism in rats, evidenced by the significantly reduced Cmax and AUC0-t of its metabolite, matrine (p < 0.05), from 2.23 ± 0.24 to 1.38 ± 0.12 µg/mL and 8.29 ± 1.34 to 5.30 ± 0.79 µg h/mL, respectively. However, due to the similar efficacy of oxymatrine and matrine, this may not compromise the anti-cancer effect of this herb-drug pair. Discussion: This study clarified the pre-clinical pharmacology and pharmacokinetic benefits and risks of the CPT-11-KA combination and provided a reference for their clinical co-administration.

Gemcitabine enhances pharmacokinetic exposure of the major components of Danggui Buxue Decoction in rat via the promotion of intestinal permeability and down-regulation of CYP3A for combination treatment of non-small cell lung cancer.

CONTEXT: Danggui Buxue Decoction (DBD), a traditional Chinese medicine formula, has the potential to enhance the antitumor effect of gemcitabine in non-small cell lung cancer (NSCLC) treatment by increasing gemcitabine's active metabolites. However, whether gemcitabine affects the pharmacokinetics of DBD's major components remains unclear. OBJECTIVE: This study evaluates the herb-drug interaction between DBD's major components and gemcitabine and validates the underlying pharmacokinetic mechanism. MATERIALS AND METHODS: The pharmacokinetics of 3.6 g/kg DBD with and without a single-dose administration of 50 mg/kg gemcitabine was investigated in Sprague-Dawley rats. The effects of gemcitabine on intestinal permeability, hepatic microsomal enzymes in rat tissues, and CYP3A overexpressing HepG2 cells were determined using western blot analysis. RESULTS: The combination of gemcitabine significantly altered the pharmacokinetic profiles of DBD's major components in rats. The Cmax and AUC of calycosin-7-O-ß-d-glucoside notably increased through sodium-glucose transporter 1 (SGLT-1) expression promotion. The AUC of ligustilide and ferulic acid was also significantly elevated with the elimination half-life (t1/2) prolonged by 2.4-fold and 7.8-fold, respectively, by down-regulating hepatic CYP3A, tight junction proteins zonula occludens-1 (ZO-1) and occludin expression. DISCUSSION AND CONCLUSIONS: Gemcitabine could modulate the pharmacokinetics of DBD's major components by increasing intestinal permeability, enhancing transporter expression, and down-regulating CYP3A. These findings provide critical information for clinical research on DBD as an adjuvant for NSCLC with gemcitabine and help make potential dosage adjustments more scientifically and rationally.

Crude polysaccharide from Danggui Buxue decoction enhanced the anti-tumor effect of gemcitabine by remodeling tumor-associated macrophages.

Tumor-associated macrophages (TAMs) with an M2-phenotype mediate gemcitabine resistance to cancer by influencing the metabolic enzymes of gemcitabine and releasing competitive deoxycytidine (dC). Our previous studies showed that Danggui Buxue Decoction (DBD), a traditional Chinese medicinal recipe, enhances the anti-tumor activity of gemcitabine in vivo and alleviates gemcitabine-induced myelosuppression. However, the material basis and exact mechanism underlying its enhanced effects remain unclear. In this study, a bioactive polysaccharide consisting of arabinose, mannose, ribose, and glucose was isolated from DBD. In vivo results demonstrated that DBD crude polysaccharide (DBDP) ameliorated gemcitabine-induced immune system disorders. Moreover, DBDP improved the sensitivity of Lewis lung carcinoma-bearing mice to gemcitabine by reshaping the tumor-promoting M2-like macrophages into tumor-inhibiting M1-phenotypes. Furthermore, in vitro results further revealed that DBDP blocked the protective effects of TAMs and M2-macrophages against gemcitabine by inhibiting the excessive secretion of dC and decreasing the high expression of cytidine deaminase. In conclusion, our results demonstrated that DBDP, as the pharmacodynamic material basis of DBD, enhanced the anti-tumor activity of gemcitabine against lung cancer in vitro and in vivo, which was associated with remodeling of the M2-phenotype.

Causal relationship between bipolar disorder and inflammatory bowel disease: A bidirectional two-sample mendelian randomization study.

Background: Growing evidence suggests a bidirectional association between bipolar disorder (BD) and inflammatory bowel disease (IBD); however, observational studies are prone to confounding, making causal inference and directional determination of these associations difficult. Methods: We performed bidirectional two-sample Mendelian randomization (MR) and selected single nucleotide polymorphisms (SNPs) associated with BD and IBD as instrumental variables (IV). SNPs and genetic associations with BD and IBD were obtained from the latest genome-wide association studies (GWAS) in Europeans (BD: cases/controls: 20352/31358; IBD: 12882/21770; Crohn's disease (CD): 5,956/14927; ulcerative colitis (UC): 6968/20464). The inverse-variance-weighted method was the major method used in MR analyses. MR-Egger, weight mode, simple mode, and weighted median were used for quality control. Results: Genetically predicted BD (per log-odds ratio increase) was significantly positively associated with risk of IBD (OR: 1.18, 95% CI: 1.04-1.33), and UC (OR = 1.19, 95% CI: 1.05-1.35), but not CD (OR = 1.18, 95% CI: 0.95-1.48). The validation analysis found that combined OR of IBD, CD, and UC increased per log-OR of BD were 1.16(95% CI: 1.02-1.31), 1.20(95% CI: 0.98-1.48) 1.17(95% CI: 1.02-1.35), respectively. In contrast, no causal relationship was identified between genetically influenced IBD and BD. Conclusion: Our results confirm a causal relationship between BD and IBD, which may influence clinical decisions on the management of BD patients with intestinal symptoms. Although the reverse MR results did not support a causal effect of IBD on BD, the effect of the IBD active period on BD remains to be further investigated.

Hepatotoxic metabolites in Polygoni Multiflori Radix- Comparative toxicology in mice.

Polygoni Multiflori Radix (PM) and Rhei radix et rhizoma (rhubarb) contain similar hepatocyte-toxic anthraquinones such as emodin (major free anthraquinone in PM), physcion and their glycosides. In clinical practice, PM hepatotoxicity has been widely reported, although rhubarb is not recognized as hepatotoxic. To clarify the substances basis (key components) of PM hepatotoxicity, based on the characteristic components' similarity within PM, rhubarb and their concocted forms, a comparative sub-acute toxicity study was designed in mice. Nine groups of mice with 28 days of oral administration of these herbal extracts or 2,3,5,4'-tetrahydroxystilbene-2-O-ß-D-glucoside (TSG, major and unique characteristic component in PM)-herb combinations were set as follows: Group-1, control; Group-2, PM ethanol-extract (PME); Group-3, PM praeparata ethanol-extract (PMPE); Group-4, Rhubarb ethanol-extract (RME); Group-5, Steamed rhubarb ethanol-extract (RMPE); Group-6, TSG; Group-7, PMPE-TSG combination; Group-8, RME-TSG combination; Group-9, RMPE-TSG combination. Each experimental group received an equivalent emodin dose of 29 mg/kg except for the TSG group, and an equivalent TSG dose of 1,345 mg/kg except for the PMPE, RME and RMPE groups. The results showed that PME, PMPE-TSG and RME-TSG induced liver lesions and biochemical abnormalities of liver function compared with the control. In contrast, PMPE, RME, RMPE, TSG and RMPE-TSG caused no liver lesions and fewer biochemical abnormalities. Considering the related components, only the co-administration of high doses of TSG and emodin-8-O-ß-D-glucoside (EMG, major anthraquinone glycoside in PM) in these groups could cause liver lesions. According to tissue distribution and correlation analysis, EMG dose was positively correlated with the high hepatic emodin and TSG exposure, and the hepatic emodin and TSG exposure were positively correlated with the biochemical abnormalities of liver function. Cell viability test in vitro showed emodin was more hepatotoxic than TSG and EMG, and mainly emodin and TSG of the three had synergistic hepatotoxic effects. Therefore, creatively using rhubarb as a reference, this study revealed that PM hepatotoxicity in mice mainly came from the integrative contribution of TSG, EMG and emodin.

Identification of degradation products in flumazenil using LC-Q-TOF/MS and NMR: Degradation pathway elucidation.

Flumazenil is an imidazobenzodiazepine derivative that antagonizes the actions of benzodiazepines. The degradation pathway elucidation plays an important role in the drug quality control. In this work, a reliable LC-Q-TOF/MS method was developed to separate and identify the degradation products of flumazenil generated in the stress testing conducted according to the ICH Q1A(R2) guideline. Fifteen degradation products were detected in total including three reported impurities and twelve unknown impurities. Based on the chromatographic and mass spectrometric data acquired, the structures of all the degradation products were identified. Besides, two major degradants were synthetized and further confirmed by NMR. The degradation pathways of flumazenil were elucidated, and the degradation characteristics of benzodiazepines were also discussed. The obtained results are of both great importance for the quality control of flumazenil and good reference for the degradation study of other benzodiazepines.

Danggui Buxue Decoction enhances the anticancer activity of gemcitabine and alleviates gemcitabine-induced myelosuppression.

ETHNOPHARMACOLOGICAL RELEVANCE: Danggui Buxue Decoction (DBD) as a traditional Chinese medicine (TCM) has been widely used to treat blood deficiency. With the immune regulation and hematopoietic effect, DBD improved the quality of life in non-small-cell lung cancer (NSCLC) patients. We previously reported that DBD sensitized the response of NSCLC to Gemcitabine (Gem); however, the synergism and attenuation mechanism on the combination of Gem and DBD has not yet been elucidated. AIM OF THE STUDY: To investigate the mechanisms of DBD in enhancing the anticancer activity of Gem and alleviating Gem-induced myelosuppression. MATERIALS AND METHODS: A549 nude mice model was established to study the effect on the combination of Gem and DBD. The organ indices, peripheral blood cells and the hematopoiesis-related cytokines were analyzed in Gem-induced myelosuppressive mice. Then we studied the whole process from Gem-induced bone marrow suppression to self-healing, and the mechanism of DBD's attenuation by the experiments of bone marrow nucleated cells (BMNCs). RESULTS: There were an enhanced anticancer effect and an improvement of hematopoietic function by combining of Gem and DBD in A549 nude mice model. DBD regulated Hu antigen R (HuR), deoxycytidine kinase (dCK) and nuclear factor erythroid 2-related factor (Nrf2), increased the expression of thrombopoietin (TPO) and granulocyte-macrophage colony stimulating factor (GM-CSF). For Gem-induced myelosuppressive mice, DBD improved the number of peripheral blood cells and the levels of hematopoiesis-related cytokines. Moreover, DBD was observed to reduce deoxyribonucleic acid (DNA) content at the G1 phase, promoted BMNCs proliferation and up-regulated cycle-related proteins. CONCLUSIONS: The results indicated that DBD not only improved the sensitivity of Gem but also alleviated Gem-induced myelosuppression. This study may provide a pharmacological basis for the combination of DBD and Gem in clinical application.

Simultaneous determination of tazarotene, clindamycin phosphate and their active metabolites in Bama mini-pig skin by LC-MS/MS: Application to the development of a tazarotene/clindamycin phosphate cream.

Topical tazarotene combined with clindamycin phosphate can significantly improve the adherence and outcomes for the treatment of acne vulgaris than monotherapy, a novel tazarotene (0.05%)/clindamycin phosphate (1.2%) cream is thus developed. However, the pharmacokinetics and potential interaction of tazarotene and clindamycin phosphate in skin when formulated together remain unknown, which should be investigated to assess this novel cream. In the present work, a sensitive and rapid LC-MS/MS method for simultaneous determination of tazarotene, clindamycin phosphate and their active metabolites tazarotenic acid, clindamycin in Bama mini-pig skin was developed and reported for the first time. After pretreatment of the skin samples, the analytes were well separated on a Hypersil BDS C8 column (4.6 × 100 mm, 2.4 µm) using 0.2% (v/v) formic acid-0.1% (w/v) ammonium acetate water solution and acetonitrile as mobile phase in linear gradient elution. Quantification of tazarotene, clindamycin phosphate and their active metabolites tazarotenic acid, clindamycin was conducted under positive electrospray ionization mode using multiple reactions monitoring detection. The LC-MS/MS method was fully validated and then applied to the dermal pharmacokinetic study of the tazarotene/clindamycin phosphate cream. According to the obtained results, tazarotene and clindamycin phosphate did not have any drug-drug interaction when they were formulated together in the cream for topical application. Their absorption and metabolism features in the skin were also characterized, which can support the clinical medication regimen of tazarotene/clindamycin phosphate cream.

Pharmacovigilance of herb-drug interactions: A pharmacokinetic study on the combination administration of herbal Kang'ai injection and chemotherapy irinotecan hydrochloride injection by LC-MS/MS.

Chinese herbal drugs are often combined with chemotherapy drugs for the treatment of cancers. However, the combination administrations often do not have scientifically sound bases established on full preclinical and clinical investigations. A commonly used anti-colon-cancer herb-drug pair, irinotecan (CPT-11) hydrochloride injection and Kang'ai (KA) injection was taken as an example to investigate the possible pharmacokinetic interactions between Chinese herbal drugs and chemotherapy injections to determine the potential adverse drug reactions (ADRs). Rats were randomly divided into three groups and received 20 mg/kg CPT-11 injection 15 min after administration of 4 mL/kg saline for the CPT-11 single administration group and 4 mL/kg KA injection for the separated co-administration group, respectively. In the pre-mixed co-administration group, rats received a mixture of 20 mg/kg CPT-11 injection and 4 mL/kg KA injection. Blood samples were collected at 10 pre-determined time points between 0 and 24 h. The tissue samples were collected at 5 and 8 min after the injections, respectively. A reliable LC-MS/MS method was established for the simultaneous determination of CPT-11 and its metabolites, SN-38, SN-38 G and APC in the rat plasma and tissue samples, after full confirmation of two injections chemical and stability compatibilities. Compared to the C0 (5129 ± 757 ng/mL) and AUC0-t (7858 ± 1307 ng h/mL) of CPT-11 in the CPT-11 single administration group, the C0 (4574 ± 371 ng/mL) and AUC0-t (8779 ± 601 ng h/mL) after the separated co-administration remained unchanged, but the pre-mixed co-administration resulted with a significant increased C0 (29,454 ± 12,080 ng/mL) and AUC0-t (15,539 ± 5165 ng h/mL) (p < 0.05). Since the exposures of CPT-11 in most tissues in the pre-mixed co-administration group were dramatically lower than the separated co-administration group, the increased CPT-11 plasma concentration may be produced by the delayed tissue distribution because of the encapsulation by the components contained in KA injection, such as polysaccharides. Similar differences were also found in its metabolite, SN-38 G. There are obvious herb-drug interactions between CPT-11 injection and KA injection after the pre-mixed co-administration. The resulting excessive CPT-11 in the plasma may lead to many serious ADRs. Therefore, the full evaluation of herb-drug interactions is necessary and inappropriate combinations should be avoided.

Differentiation of the midbrain dopaminergic pathways during mouse development.

Dopaminergic (DA) neurons in the substantia nigra (SN) and ventral tegmental area (VTA) of the midbrain project to the dorsolateral caudate/putamen and to the ventromedially located nucleus accumbens, respectively, establishing the mesostriatal and the mesolimbic pathways. Disruptions in this system have been implicated in Parkinson's disease, drug addiction, schizophrenia, and attention deficit hyperactivity disorder. However, progress in our understanding has been hindered by a lack of knowledge of how these pathways develop. In this study, different retrograde tracers, placed into the dorsolateral caudate/putamen and the nucleus accumbens, were used to analyze the development of the dopaminergic pathways. In embryonic day 15 mouse embryos, both SN and VTA neurons, as well as their fibers, were doubly labeled by striatal injections into the dorsolateral and ventromedial striatum. However, by birth, the SN DA neurons were labeled exclusively by DiA placed in the dorsolateral striatum, and the VTA DA neurons were labeled only by DiI injected into the ventromedial striatum. These data suggest that initial projections from midbrain DA neurons target nonspecifically to both the dorsolateral striatum and the nucleus accumbens. Later during development, the separate mesostriatal and mesolimbic pathways differentiate through the selective elimination of mistargeted collaterals.

Corpus callosum deficiency in transgenic mice expressing a truncated ephrin-A receptor.

The A-class of the erythropoietin-producing hepatocellular carcinoma cell-derived (EphA) tyrosine kinase receptors and their ligands, the A-ephrins, play critical roles in the specification of topographic axon projection maps during development. In this study, the role of the EphA subfamily in callosal projections was investigated using transgenic mice expressing a kinase deletion mutant of EphA5. In approximately half of these transgenic mice, cerebral cortical neurons in various cortical regions (primary and secondary somatosensory cortices and frontal as well as visual areas) failed to project to the contralateral cortex. When commissural axons were examined with DiI labeling, few callosal fibers were found to traverse the midline in both the adult and neonatal transgenic mice. This defect in callosal development correlates with the expression of the transgene, because neurons in the superficial layers of the motor cortex, where transgene expression is low, show normal contralateral projection through the corpus callosum. In addition, multiple EphA receptors are expressed in callosal neurons and ephrin-A5 stimulates neurite outgrowth of callosal neurons in vitro. The midline glia structures important for callosal axon midline crossing appear normal in the transgenic mice, suggesting that the defects are unrelated to defective guidance structures at the midline. These observations suggest critical functions for EphA receptor in establishing callosal connections during brain development.