Effects of Clarithromycin and Ketoconazole on FK506 Metabolism in Different CYP3A4 Genotype Recombinant Metabolic Enzyme Systems.

OBJECTIVE: This study aimed to investigate the effects of clarithromycin and ketoconazole on the pharmacokinetic properties of tacrolimus in different CYP3A4 genotype recombinant metabolic enzyme systems, so as to understand the drug interactions and their mechanisms further. METHOD: The experiment was divided into three groups: a blank control group, CYP3A4*1 group and CYP3A4*18 recombinant enzyme group. Each group was added with tacrolimus (FK506) of a series of concentrations. Then 1 umol/L clarithromycin or ketoconazole was added to the recombinant enzyme group and incubated in the NADPH system for 30 minutes to examine the effects of clarithromycin and ketoconazole on the metabolizing enzymes' activity of different genotypes. The remaining concentration of FK506 in the reaction system was determined using UPLC-MS/MS, and the enzyme kinetic parameters were calculated using the software. RESULTS: The metabolism of CYP3A4*18 to FK506 was greater than that of CyP3А4*1B. Compared with the CYP3A4*1 group, the metabolic rate and clearance of FK506 in the CYP3A4*18 group significantly increased, with Km decreasing. Clarithromycin and ketoconazole inhibit the metabolism of FK506 by affecting the enzyme activity of CYP3A4*1B and CYP3A4*18B. After adding clarithromycin or ketoconazole, the metabolic rate of FK506 significantly decreased in CYP3A4*1 and CYP3A4*18, with Km increasing, Vmax and Clint decreasing. CONCLUSION: Compared with CYP3A4*1, CYP3A4*18 has a greater metabolism of FK506, clarithromycin and ketoconazole can inhibit both the enzymatic activities of CYP3A4*1 and CYP3A4*18, consequently affecting the metabolism of FK506 and the inhibitory on CYP3A4*1 is stronger.

Mechanistic target of rapamycin in regulating macrophage function in inflammatory cardiovascular diseases.

The mechanistic target of rapamycin (mTOR) is evolutionarily conserved from yeast to humans and is one of the most fundamental pathways of living organisms. Since its discovery three decades ago, mTOR has been recognized as the center of nutrient sensing and growth, homeostasis, metabolism, life span, and aging. The role of dysregulated mTOR in common diseases, especially cancer, has been extensively studied and reported. Emerging evidence supports that mTOR critically regulates innate immune responses that govern the pathogenesis of various cardiovascular diseases. This review discusses the regulatory role of mTOR in macrophage functions in acute inflammation triggered by ischemia and in atherosclerotic cardiovascular disease (ASCVD) and heart failure with preserved ejection fraction (HFpEF), in which chronic inflammation plays critical roles. Specifically, we discuss the role of mTOR in trained immunity, immune senescence, and clonal hematopoiesis. In addition, this review includes a discussion on the architecture of mTOR, the function of its regulatory complexes, and the dual-arm signals required for mTOR activation to reflect the current knowledge state. We emphasize future research directions necessary to understand better the powerful pathway to take advantage of the mTOR inhibitors for innovative applications in patients with cardiovascular diseases associated with aging and inflammation.

MIF is a critical regulator of mononuclear phagocytic infiltration in hepatocellular carcinoma.

Immunotherapy targeting tumor-associated macrophages (TAMs) is a promising approach to treating cancer. However, the limited drug targets and ambiguous mechanisms impede the development of clinical immunotherapy strategies. To elucidate the underlying processes involved in mononuclear phagocyte (MNP) infiltration and phenotypic changes in hepatocellular carcinoma (HCC), we integrated single-cell RNA-sequencing data from 100,030 cells derived from patients with HCC and healthy individuals and compared the phenotypes and origins of the MNPs in the tumor core, tumor periphery, adjacent normal tissue, and healthy liver samples. Using machine learning and multi-omics analyses, we identified 445 infiltration-associated genes and potential drug targets affecting this process. Through in vitro experiments, we found that the expression of macrophage migration inhibitory factor (MIF) is the upstream regulator of secreted phosphoprotein 1 (SPP1) and promote migration in TAMs. Our findings also indicate that MIF promotes tumor metastasis and invasion and is a promising potential target for treating HCC.

Effects of clarithromycin on the pharmacokinetics of tacrolimus and expression of CYP3A4 and P-glycoprotein in rats.

The objective of this study was to investigate the effect of clarithromycin on the pharmacokinetics of tacrolimus in rats and better understand its mechanism. In the control group (n = 6), rats received a single oral dose of 1 mg tacrolimus on day 6. In the experimental group (n = 6), rats received 0.25 g of clarithromycin daily for five consecutive days and then a single oral dose of 1 mg tacrolimus on day 6. Orbital venous blood (250 µL) was collected at 0, 0.25, 0.50, 0.75, 1, 2, 4, 8, 12, and 24 h before and after tacrolimus administration. Blood drug concentrations were detected via mass spectrometry. Small intestine and liver tissue samples were collected after rats were euthanized via dislocation, and CYP3A4 and P-glycoprotein (P-gp) protein expression was determined using western blotting. Clarithromycin increased the blood tacrolimus concentration and affected its pharmacokinetic properties in rats. Compared with those in the control group, the AUC0-24 , AUC0-∞ , AUMC(0-t) , and AUMC(0-∞) of tacrolimus in the experimental group were significantly increased, whereas the CLz/F was significantly lower (P < 0.01). Simultaneously, clarithromycin significantly inhibited CYP3A4 and P-gp expression in the liver and intestine. Protein expression of CYP3A4 and P-gp in the liver and the intestinal tract was significantly downregulated in the intervention group compared with that in the control group. Clarithromycin significantly inhibited the protein expression of CYP3A4 and P-gp in the liver and intestine, thereby increasing the mean blood concentration and significantly increasing the AUC of tacrolimus.

A Novel TrxR1 Inhibitor Regulates NK and CD8+ T Cell Infiltration and Cytotoxicity, Enhancing the Efficacy of Anti-PD-1 Immunotherapy against Hepatocarcinoma.

Hepatocellular carcinoma (HCC) has the third highest cancer-related mortality rate globally. The immunosuppressive microenvironment of HCC limits effective treatment options. HCC cells and associated microenvironmental factors suppress NK and T cell infiltration and cytotoxic activities. The abnormal number or function of NK and T cells leads to a lack of immune surveillance. Recently, immunotherapy targeting PD-1 and PD-L1 has been shown to activate functionally exhausted cytotoxic immune cells in some solid tumors. However, the response rate and therapeutic efficacy against solid tumors with little lymphocyte infiltration are limited, especially for HCC. Therefore, new targets and therapeutics that induce tumor cell apoptosis and overcome the problem of depletion of immune cells, thereby inhibiting the immune escape of HCC cells, are urgently required. Butaselen (2-bis[2-(1,2-benzisothiazol-2(2H)-ketone)]butane), an organic molecule containing selenium, is a new type of thioredoxin reductase inhibitor. In this study, we found that butaselen promoted NK and T cell activity and infiltration in the tumor microenvironment in HCC-bearing mice by enhancing the expression of CXCR3, NKG2D, and their respective ligands. When used alone, it can significantly inhibit tumor growth and exert a synergistic effect in combination with PD-1 blockade. We suggested the role of the thioredoxin reductase system in the regulation of the tumor immunosuppressive microenvironment and developed a new effective therapeutic molecule for HCC, revealing the mechanism of butaselen in inhibiting tumor cell immune escape.

Lithium Cholesterol Sulfate: A Novel and Potential Drug for Treating Alzheimer's Disease and Autism Spectrum Disorder.

BACKGROUND AND OBJECTIVE: Recent studies have shown that lithium treatment can reduce symptoms of Alzheimer's disease (AD) and Autism Spectrum Disorder (ASD). However, the present lithium salts clinically available have serious short-term and long-term side effects which requires frequent monitoring of blood chemistry and plasma lithium levels so as to avoid toxicity. Consequently, there is a demand for a safer and more effective lithium formulation to treat these diseases. METHODS: Hence, we firstly synthesized lithium cholesterol sulfate (LiCS) and compared its pharmacological effects with that of lithium chloride (LiCl) and sodium cholesterol sulfate (NaCS) on markers of neurodegenerative disease in cell cultures. RESULTS: LiCS was more potent than LiCl in increasing inhibitory GSK3ß (Ser9) phosphorylation (pGSK3ß) in both CHO and SH-SY5Y cells. These agents dose-dependently increased pGSK3ß, starting at 10 µM for LiCS and 60µM for LiCl and maximally by approximately 100% at 60 µM for LiCS and 1.25 mM for LiCl, without altering total GSK3ß levels. In HEK293/tau cells, LiCS reduced tau (Thr231) phosphorylation (ptau) starting at 10 µM and maximally by 63% at 40 µM without altering total tau levels, but ptau levels were not altered by LiCl at any dose between 60 µM and 1.25 mM. In BV2 cells, LiCS and LiCl decreased LPS-induced TNFα levels, starting at 20 µM for LiCS and 5 mM for LiCl, and maximally by approximately 30% at 80 µM for LiCS and 20 mM for LiCl. NaCS at any dose between 5 and 90 µM did not alter pGSK3ß, ptau or LPS-induced TNFα. CONCLUSION: LiCS may become a new drug with good pharmacological potential for the treatment of neurodegenerative disorders such as AD and ASD by allowing lithium to more readily access intracellular pathological processes.

OATP1B1 Plays an Important Role in the Transport and Treatment Efficacy of Sorafenib in Hepatocellular Carcinoma.

BACKGROUND: Sorafenib is an anticancer drug used in the treatment of unresectable hepatocellular carcinoma and advanced renal cell carcinoma. It is a substrate for the human OATP1B1. This study is aimed at assessing the role of OATP1B1 in transportation and uptake of sorafenib in hepatocellular carcinoma and how OATP1B1 affects the pharmacodynamics of sorafenib in vitro and in vivo. METHODS: Sorafenib transport was measured in HepG2, HepG2-OATP1B1∗1a, HepG2-OATP1B1∗1b, HepG2-OATP1B1∗15, LO2, LO2-OATP1B1∗1a, LO2-OATP1B1∗1b, and LO2-OATP1B1∗15 cells, as well as in HepG2 cells transfected with miR-148a mimics. The viability and apoptosis rate of cells treated with sorafenib were evaluated. A liver cancer rat model was established to explore the pharmacokinetics and pharmacodynamics of sorafenib after overexpression of Oatp2. RESULTS: Changes in expression and genetic mutations of OATP1B1 significantly affected the uptake of sorafenib in HepG2 and LO2 transgenic cells, and the uptake of sorafenib was higher in HepG2 than LO2. Genetic mutations of OATP1B1 significantly affected the cell viability and apoptosis rate of HepG2 cells after sorafenib treatment. Compared to control group, the uptake of sorafenib in miR-148a mimic-transfected HepG2 cells was decreased, and the cell viability was increased. PCN significantly increased the expression of Oatp2 and affected the pharmacokinetics of sorafenib. Vascular endothelial growth factor levels and microvascular density in tumor-adjacent tissues decreased significantly, suggesting that increased Oatp2 expression improves the treatment effect of sorafenib in a rat model of liver cancer. CONCLUSIONS: OATP1B1 plays an important role in the pharmacokinetics and pharmacodynamics of sorafenib in hepatocellular carcinoma.

Uptake of Aß by OATPs might be a new pathophysiological mechanism of Alzheimer disease.

BACKGROUND: The accumulation of neurotoxic amyloid-beta (Aß) in the brain is a characteristic of Alzheimer's disease (AD), at the same time, it is possible alterations of liver function could affect brain Aß levels through changes in blood Aß concentration. Over the last decade, a number of reports have shown that P-glycoprotein (encoded by ABC1B1) actively mediates the efflux transport of Aß peptides. However, the mechanism by which Aß peptides enter the cells is not clear. In the preliminary study, we found that the protein expression of organic anion transporting Polypeptide 1a4 (OATP1B1) in the liver tissue of mice with AD was significantly higher than that in the normal mice. In contrast, the protein expression of Oatp1a4 in the brain significantly decreased in mice with AD. OATP1B1, an important drug transporter might be related to the pathophysiology of AD. RESULTS: In this study, we established an OATP1B1-GFP-HEK293T cell model to confirm the OATP1B1 mediated transport of Aß1-42. Compared to the control group of GFP-HEK293Tcells, the uptake of Aß1-42 protein in the OATP1B1-GFP-HEK293T group increased significantly with the increase in concentration of Aß1-42, and also increased significantly with an increase in the duration of incubation. Similar results were observed in the flow cytometry experiment, and the uptake of Aß1-42in HEK293T-OATP1B1 cells was almost twice that in the control group. These results indicate that OATPs may act as an important "carrier" for the transport of Aß1-42 from the blood to the tissues, including liver and brain. CONCLUSIONS: This is a novel and interesting finding and OATP1B1 can be investigated as a new treatment target for AD.

Therapeutic Effects of an Inhibitor of Thioredoxin Reductase on Liver Fibrosis by Inhibiting the Transforming Growth Factor-ß1/Smads Pathway.

Liver fibrosis is an important stage in the progression of liver injury into cirrhosis or even liver cancer. Hepatic stellate cells (HSCs) are induced by transforming growth factor-ß1 (TGF-ß1) to produce α-smooth muscle actin (α-SMA) and collagens in liver fibrosis. Butaselen (BS), which was previously synthesized by our group, is an organic selenium compound that exerts antioxidant and tumor cell apoptosis-promoting effects by inhibiting the thioredoxin (Trx)/thioredoxin reductase (TrxR) system. The aim of this study was to investigate the potential effects of BS on liver fibrosis and explore the underlying molecular mechanisms of its action. Liver fibrosis models were established using male BALB/c mice through intraperitoneal injection of CCl4. BS was administered orally once daily at a dose of 36, 90, or 180 mg/kg. Silymarin (Si), which is a drug used for patients with nonalcoholic fatty liver disease and nonalcoholic steatohepatitis, was administered at a dose of 30 mg/kg per day as a control. The action mechanisms of BS against liver fibrosis progression were examined in HSCs. The study revealed that the activity and expression levels of TrxR were elevated in the mouse liver and serum after CCl4-induced liver fibrosis. Oral administration of BS relieved the pathological state of mice with liver fibrosis, showing significant therapeutic effects against liver fibrosis. Moreover, BS not only induced HSC apoptosis but also inhibited the production of α-SMA and collagens by HSCs by downregulating the TGF-ß1 expression and blocking the TGF-ß1/Smads pathway. The results of the study indicated that BS inhibited liver fibrosis by regulating the TGF-ß1/Smads pathway.

Systematic Review and Pharmacological Considerations for Chloroquine and Its Analogs in the Treatment for COVID-19.

COVID-19 has been announced pandemic by WHO and over 17,000,000 people infected (Till April 21st 2020). The disease is currently under control in China, with a curative rate of 86.8%. Chloroquine (CQ) is an old anti-malarial drug with good tolerability, which had proved to be effective in previous SARS-coronavirus, which spread and disappeared between 2002-2003. In vitro studies demonstrated the efficacy of CQ in curing COVID-19. Consequently, via analytical PBPK modeling, a further preliminary clinical trial has proved the efficacy and safety of CQ in China., and multiple clinical trials were registered and approved to investigate the activity of other analogs of CQ against COVID-19. We have listed all the clinical trials and made a meta-analysis of published data of hydroxychloroquine (HCQ). HCQ could increase the CT improvement and adverse reactions (ADRs) significantly though there was considerable heterogeneity among current researches. Actually, CQ and its analogs have unique pharmacokinetic characteristics, which would induce severe side effects in some circumstances. We have then summarized pharmacological considerations for these drugs so as to provide to the busy clinicians to avoid potential side effects when administered CQ or its analogs to COVID-19 patients, especially in the elderly, pediatrics, and pregnancies.

Pharmacotherapics Advice in Guidelines for COVID-19.

Since December 2019 to May 2020, coronavirus disease 2019 (COVID-19) has infected over 6 million people worldwide. Due to its sudden and rapid outbreak, effective treatment for COVID-19 is scarce. Based on national clinical trials of novel treatments, China, Italy, Germany, and other countries and organizations have published multiple guidelines for COVID-19 and advised many medicines, such as chloroquine and tocilizumab. In this paper, we summarize the pharmacotherapy for COVID-19 according to those guidelines, highlight updates of the pharmacotherapy guidelines, and review the efficacy and safety of the indicated anti-COVID-19 drugs.

Berberine Promotes OATP1B1 Expression and Rosuvastatin Uptake by Inducing Nuclear Translocation of FXR and LXRα.

Berberine, a quinoline alkaloid, can be used in combination with statins to enhance hypolipidemic effects and reduce the dose and side effects of statins. The hypolipidemic effects of statins in the liver are mainly regulated by organic anion transporting polypeptides (OATPs), and the expression of OATPs is regulated by nuclear receptors. Berberine has been reported to affect nuclear receptors. However, whether berberine affects the uptake of statins by regulating nuclear receptor-mediated expression of OATPs remains to be determined. The aim of this study was to investigate the effects of berberine on the expression of OATP1B1 in HepG2 and explore the underlying mechanism. In HepG2 cells, 10-50 µM berberine significantly increased the uptake of rosuvastatin by inducing the expression of OATP1B1 mRNA and protein. Dual-Luciferase reporter assay showed that luciferase activity of hFXR and hLXRα activated OATP1B1 promoter was increased by 2.5-50 µM berberine in a concentration-dependent manner, with half-maximal effective concentration (EC50) of 12.19 ± 0.86 and 32.15 ± 2.32 µM, respectively. In addition, after silencing FXR or LXRα by small interfering RNA (siRNA), berberine-induced OATP1B1 expression was significantly attenuated. Western blot analysis of FXR and LXRα protein levels in the cytoplasm and nucleus of HepG2 cells after treatment with berberine showed that berberine induced nuclear translocation and activation of FXR and LXRα. In conclusion, berberine-induced nuclear translocation of FXR and LXRα could activate OATP1B1 promoter, resulting in enhanced expression of OATP1B1 and increased uptake of rosuvastatin.

Expression of Oatp2 in the Brain and Liver of Alzheimer Disease Mouse Model.

The purpose of this study was to explore the expression of Oatp2 transporter in the liver and brain of Alzheimer's disease (AD) mice. The results showed that the protein expression of Oatp2 in the brain significantly decreased in Alzheimer disease mice. On the contrary, protein expression of Oatp2 in liver tissue of AD mice was significantly higher compared with that in normal mice. For mRNA expression of Oatp2, the results showed that, compared with normal mice, it was significantly lower in the brain but significantly higher in liver tissue. Based on the current research, we cannot confirm the relationship between Oatp2 expression and Alzheimer disease. However, it may be a very novel and interesting discovery and may become a new target for the pathogenesis, drug development, and treatment of AD.

MFN2 silencing promotes neural differentiation of embryonic stem cells via the Akt signaling pathway.

Mitofusin 2 (MFN2) is a regulatory protein participating in mitochondria dynamics, cell proliferation, death, differentiation, and so on. This study aims at revealing the functional role of MFN2 in the pluripotency maintenance and primitive differetiation of embryonic stem cell (ESCs). A dox inducible silencing and routine overexpressing approach was used to downregulate and upregulate MFN2 expression, respectively. We have compared the morphology, cell proliferation, and expression level of pluripotent genes in various groups. We also used directed differentiation methods to test the differentiation capacity of various groups. The Akt signaling pathway was explored by the western blot assay. MFN2 upregulation in ESCs exhibited a typical cell morphology and similar cell proliferation, but decreased pluripotent gene markers. In addition, MFN2 overexpression inhibited ESCs differentiation into the mesendoderm, while MFN2 silencing ESCs exhibited a normal cell morphology, slower cell proliferation and elevated pluripotency markers. For differentiation, MFN2 silencing ESCs exhibited enhanced three germs' differentiation ability. Moreover, the protein levels of phosphorylated Akt308 and Akt473 decreased in MFN2 silenced ESCs, and recovered in the neural differentiation process. When treated with the Akt inhibitor, the neural differentiation capacity of the MFN2 silenced ESCs can reverse to a normal level. Taken together, the data indicated that the appropriate level of MFN2 expression is essential for pluripotency and differentiation capacity in ESCs. The increased neural differentiation ability by MFN2 silencing is strongly related to the Akt signaling pathway.

Identification of cytochrome P450 isoenzymes involved in the metabolism of 23-hydroxybetulinic acid in human liver microsomes.

Context: 23-Hydroxybetulinic acid (23-HBA), a major active constituent of Pulsatilla chinensis (Bunge) Regel (Ranunculaceae), exhibits potential antitumor activity. Its metabolism, however, has not yet been studied.Objective: This study focuses on the metabolism of 23-HBA in vitro by human liver microsomes.Materials and methods: The metabolic kinetics of 23-HBA (0.5-100 µM) and the effects of selective CYP450 (CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A4) inhibitors on metabolism of 23-HBA were evaluated in human liver microsomes incubation system and then determined by LC-MS method. The Michaelis-Menten parameters Km and Vmax were initially estimated by analysing Lineweaver-Burk plot. The clearance (CLint) was also calculated.Results: The Vmax, Km, and CLint of 23-HBA were 256.41 ± 11.20 pmol/min/mg, 11.10 ± 1.07 µM, and 23.10 ± 1.32 µL/min/mg, respectively. The metabolism of 23-HBA was significantly inhibited by furafylline (0.05 µM, p < 0.01) and ketoconazole (0.02 µM, p < 0.05). Ticlopidine (1.3 µM, p < 0.05) could inhibit the metabolism of 23-HBA, while the other inhibitors (sulfaphenazole and quinidine) showed nonsignificant inhibition on the metabolism of 23-HBA.Discussion and conclusions: This is the first investigation of the metabolism of 23-HBA in human liver microsomes. The in vitro study indicates that CYP1A2 and CYP3A4 are mainly involved in the metabolism of 23-HBA. Special attention should be given to the pharmacokinetic and clinical outcomes when 23-HBA was co-administrated with other compounds mainly undergoing CYP1A2/CYP3A4-mediated metabolism. Further studies are needed to evaluate the significance of this interaction and strengthen the understanding of traditional Chinese medicine.

A Review for Lithium: Pharmacokinetics, Drug Design, and Toxicity.

Lithium as a mood stabilizer has been used as the standard pharmacological treatment for Bipolar Disorder (BD) for more than 60 years. Recent studies have also shown that it has the potential for the treatment of many other neurodegenerative disorders, including Alzheimer's, Parkinson's and Huntington's disease, through its neurotrophic, neuroprotective, antioxidant and anti-inflammatory actions. Therefore, exploring its pharmacokinetic features and designing better lithium preparations are becoming important research topics. We reviewed many studies on the pharmacokinetics, drug design and toxicity of lithium based on recent relevant research from PubMed, Web of Science, Elsevier and Springer databases. Keywords used for searching references were lithium, pharmacology, pharmacokinetics, drug design and toxicity. Lithium is rapidly and completely absorbed from the gastrointestinal tract after oral administration. Its level is initially highest in serum and then is evidently redistributed to various tissue compartments. It is not metabolized and over 95% of lithium is excreted unchanged through the kidney, but different lithium preparations may have different pharmacokinetic features. Lithium has a narrow therapeutic window limited by various adverse effects, but some novel drugs of lithium may overcome these problems. Various formulations of lithium have the potential for treating neurodegenerative brain diseases but further study on their pharmacokinetics will be required in order to determine the optimal formulation, dosage and route of administration.

Pharmacokinetic analysis of plasma bicyclol by liquid chromatography-tandem mass spectrometry.

Bicyclol is a synthetic drug widely used to treat chronic hepatitis B. This study aimed to develop a selective, sensitive and high-throughput liquid chromatography-tandem mass spectrometric method for the detection of bicyclol in human plasma. Bicyclol was detected using a multiple reaction monitoring mode, with ammonium adduct ions (m/z 408.2) as the precursor ion and the [M-CH3 ]+ ion (m/z 373.1) subjected to demethylation as the product ion. Chromatographic separation was achieved using a Zobax Eclipse XDB-C18 column with a gradient elution and a mobile phase of 2 mm ammonium formate and acetonitrile. Bicyclol was extracted from plasma matrix by precipitation. A linear detection response was obtained for bicyclol ranging from 0.500 to 240 ng/mL, and the lower limit of quantification was 0.500 ng/mL. The intra- and inter-day precisions were all ≤7.4%, and the accuracies were within ±6.0%. The extraction recovery was >95.9%, and the matrix effects were between 96.0% and 108%. Bicyclol was found to be unstable in human plasma at room temperature, but the degradation was minimized by conducting sample collection and preparation in an ice bath. The validated method was successfully applied to investigate the pharmacokinetics of bicyclol tablets in six healthy Chinese volunteers.