Selective Photoaffinity Probe for Monitoring Farnesoid X Receptor Expression in Cultured Cells.

Farnesoid X receptor (FXR), a member of the nuclear receptor superfamily, is a vital ligand-activated transcriptional factor, which is highly expressed in the liver, intestine, and adrenal gland. However, FXR homeostasis is influenced by many factors, such as diet and circadian rhythm, and the expression of FXR differs in diverse organs. Currently, there is no method to monitor the FXR homeostasis in real time, which restricts us from further investigating the function of FXR under physiological and pathological conditions. In this project, classic FXR agonists were selected to be modified to targeting FXR. The photo-cross-linking diazirine group and alkynyl, a click reaction group, were incorporated to the ligands. Through biorthogonal reaction, fluorophore was linked to the ligands to realize the monitoring of FXR expression in cells.

Silybin alleviates hepatic lipid accumulation in methionine-choline deficient diet-induced nonalcoholic fatty liver disease in mice via peroxisome proliferator-activated receptor α.

Nonalcoholic fatty liver disease (NAFLD) is regarded as the most common liver disease with no approved therapeutic drug currently. Silymarin, an extract from the seeds of Silybum marianum, has been used for centuries for the treatment of various liver diseases. Although the hepatoprotective effect of silybin against NAFLD is widely accepted, the underlying mechanism and therapeutic target remain unclear. In this study, NAFLD mice caused by methionine-choline deficient (MCD) diet were orally administrated with silybin to explore the possible mechanism and target. To clarify the contribution of peroxisome proliferator-activated receptor α (PPARα), PPARα antagonist GW6471 was co-administrated with silybin to NAFLD mice. Since silybin was proven as a PPARα partial agonist, the combined effect of silybin with PPARα agonist, fenofibrate, was then evaluated in NAFLD mice. Serum and liver samples were collected to analyze the pharmacological efficacy and expression of PPARα and its targets. As expected, silybin significantly protected mice from MCD-induced NAFLD. Furthermore, silybin reduced lipid accumulation via activating PPARα, inducing the expression of liver cytosolic fatty acid-binding protein, carnitine palmitoyltransferase (Cpt)-1a, Cpt-2, medium chain acyl-CoA dehydrogenase and stearoyl-CoA desaturase-1, and suppressing fatty acid synthase and acetyl-CoA carboxylase α. GW6471 abolished the effect of silybin on PPARα signal and hepatoprotective effect against NAFLD. Moreover, as a partial agonist for PPARα, silybin impaired the powerful lipid-lowering effect of fenofibrate when used together. Taken together, silybin protected mice against NAFLD via activating PPARα to diminish lipid accumulation and it is not suggested to simultaneously take silybin and classical PPARα agonists for NAFLD therapy.

Drug Discovery Inspired from Nuclear Receptor Sensing of Microbial Signals.

Host-microbiota interactions are vital for diverse pathophysiological events and may be targeted for innovative therapeutics. Nuclear receptors (NRs) are versatile host sensors of microbial signals that coordinate diverse environmental cues with local and remote adaptions. Harnessing NR-mediated sensory machinery could provide an alternative lynchpin for gut microbiota-oriented drug discovery strategy.

Gasdermin E-derived caspase-3 inhibitors effectively protect mice from acute hepatic failure.

Programmed cell death (PCD), including apoptosis, apoptotic necrosis, and pyroptosis, is involved in various organ dysfunction syndromes. Recent studies have revealed that a substrate of caspase-3, gasdermin E (GSDME), functions as an effector for pyroptosis; however, few inhibitors have been reported to prevent pyroptosis mediated by GSDME. Here, we developed a class of GSDME-derived inhibitors containing the core structure of DMPD or DMLD. Ac-DMPD-CMK and Ac-DMLD-CMK could directly bind to the catalytic domains of caspase-3 and specifically inhibit caspase-3 activity, exhibiting a lower IC50 than that of Z-DEVD-FMK. Functionally, Ac-DMPD/DMLD-CMK substantially inhibited both GSDME and PARP cleavage by caspase-3, preventing apoptotic and pyroptotic events in hepatocytes and macrophages. Furthermore, in a mouse model of bile duct ligation that mimics intrahepatic cholestasis-related acute hepatic failure, Ac-DMPD/DMLD-CMK significantly alleviated liver injury. Together, this study not only identified two specific inhibitors of caspase-3 for investigating PCD but also, more importantly, shed light on novel lead compounds for treating liver failure and organ dysfunctions caused by PCD.

Monocyte-derived multipotent cell delivered programmed therapeutics to reverse idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a highly heterogeneous and fatal disease. However, IPF treatment has been limited by the low drug delivery efficiency to lungs and dysfunctional "injured" type II alveolar epithelial cell (AEC II). Here, we present surface-engineered nanoparticles (PER NPs) loading astaxanthin (AST) and trametinib (TRA) adhered to monocyte-derived multipotent cell (MOMC) forming programmed therapeutics (MOMC/PER). Specifically, the cell surface is designed to backpack plenty of PER NPs that reach directly to the lungs due to the homing characteristic of the MOMC and released PER NPs retarget injured AEC II after responding to the matrix metalloproteinase-2 (MMP-2) in IPF tissues. Then, released AST can enhance synergetic effect of TRA for inhibiting myofibroblast activation, and MOMC can also repair injured AEC II to promote damaged lung regeneration. Our findings provide proof of concept for developing a strategy for cell-mediated lung-targeted delivery platform carrying dual combined therapies to reverse IPF.

Ion micro-distribution in varying aged leaves in salt-treated cucumber seedlings.

Na+ distribution is one of the most important strategies for plant resistance to salt stress. The way of Na+ compartmentation in different aged leaves has been controversial, especially at the cell and sub-cellular level. The roles that Na+ and K+/Na+ play the key role in photosynthesis need to be further verified. In this study, using two cucumber cultivars Cucumis sativus L. cv. zhongnong 8 (ZN8, relatively salt tolerant) and Cucumis sativus L.cv. Jinchun 4 (JC4, salt sensitive) as experiment material, we analyzed the mode of ion compartmentation of Na+ in organelles in different aged leaves and determined which factors (the organelles' Na+ or K+/Na+) affect leaf photosynthesis, using high-pressure freezing and freeze-substitution, Ultrathin sectioning technique and X-ray. The main results: 1. The sub-cellular trends of Na+ accumulation was cell wall > vacuole > cytoplasm > chloroplasts; 2. The Na+ accumulation in cytoplasm and chloroplasts was similar in different aged leaves and in seedlings of different salt tolerance cultivars; 3. The K+/Na+ ratio is the main factor that affects the photosynthesis of the same aged leaves in our experiment. A weak capacity for ion compartmentation may be an important reason leading to salt sensitivity.

Inhibitory Effects of Danshen components on CYP2C8 and CYP2J2.

The use of Chinese herbal medicines and natural products has become increasingly popular in both China and Western societies as an alternative medicine for the treatment of diseases or as a health supplement. Danshen, the dried root of Salvia miltiorrhiza (Fam.Labiatae), which is rich in phenolic acids and tanshinones, is a widely used herbal medicine for the treatment of cardio-cerebrovascular diseases. The goal of this study was to examine the inhibitory effects of fifteen components derived from Danshen on CYP2C8 and CYP2J2, which are expressed both in human liver and cardiovascular systems. Recombinant CYP2C8 and CYP2J2 were used, and the mechanism, kinetics, and type of inhibition were determined. Taxol 6-hydroxylation and astemizole O-desmethyastemizole were determined as probe activities for CYP2C8 and CYP2J2, respectively. Metabolites formations were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The results demonstrated that salvianolic acid A was a competitive inhibitor of CYP2C8 (Ki = 2.5 µM) and mixed-type inhibitor of CYP2J2 (Ki = 7.44 µM). Salvianolic acid C had moderate noncompetitive and mixed-type inhibitions on CYP2C8 (Ki = 4.82 µM) and CYP2J2 (Ki = 5.75 µM), respectively. Tanshinone IIA was a moderate competitive inhibitor of CYP2C8 (Ki = 1.18 µM). Dihydrotanshinone I had moderate noncompetitive inhibition on CYP2J2 (Ki = 6.59 µM), but mechanism-based inhibition on CYP2C8 (KI = 0.43 µM, kinact = 0.097 min-1). Tanshinone I was a moderate competitive inhibitor of CYP2C8 (Ki = 4.20 µM). These findings suggested that Danshen preparations appear not likely to pose a significant risk of drug interactions mediated by CYP2C8 after oral administration; but their inhibitory effects on intestinal CYP2J2 mediated drug metabolism should not be neglected when they are given orally in combination with other drugs. Additionally, this study provided novel insights into the underling pharmacological mechanisms of Danshen components from the perspective of CYP2C8 and CYP2J2 inhibition.

Ginsenosides synergize with mitomycin C in combating human non-small cell lung cancer by repressing Rad51-mediated DNA repair.

The use of ginseng extract as an adjuvant for cancer treatment has been reported in both animal models and clinical applications, but its molecular mechanisms have not been fully elucidated. Mitomycin C (MMC), an anticancer antibiotic used as a first- or second-line regimen in the treatment for non-small cell lung carcinoma (NSCLC), causes serious adverse reactions when used alone. Here, by using both in vitro and in vivo experiments, we provide evidence for an optimal therapy for NSCLC with total ginsenosides extract (TGS), which significantly enhanced the MMC-induced cytotoxicity against NSCLC A549 and PC-9 cells in vitro when used in combination with relatively low concentrations of MMC. A NSCLC xenograft mouse model was used to confirm the in vivo synergistic effects of the combination of TGS with MMC. Further investigation revealed that TGS could significantly reverse MMC-induced S-phase cell cycle arrest and inhibit Rad51-mediated DNA damage repair, which was evidenced by the inhibitory effects of TGS on the levels of phospho-MEK1/2, phospho-ERK1/2 and Rad51 protein and the translocation of Rad51 from the cytoplasm to the nucleus in response to MMC. In summary, our results demonstrate that TGS could effectively enhance the cytotoxicity of MMC against NSCLC cells in vitro and in vivo, thereby revealing a novel adjuvant anticancer mechanism of TGS. Combined treatment with TGS and MMC can significantly lower the required concentration of MMC and can further reduce the risk of side effects, suggesting a better treatment option for NSCLC patients.

Comparison of bioactive components and pharmacological activities of ophiopogon japonicas extracts from different geographical origins.

Ophiopogon japonicus (Linn. f.) Ker-Gawl (O. japonicas), mainly cultivated in Sichuan and Zhejiang province in China, has different bioactive components and therefore their pharmacological activities. To explain the different clinical efficacy of O. japonicas derived preparations, herein we report differences of pharmacological activities between Sichuan and Zhejiang O. japonicas and behind them the exact differences of bioactive components. Based on a LC/MS-IT-TOF method, the differences of bioactive components between Sichuan and Zhejiang O. japonicas extracts were analyzed and respective characteristic components were picked out. We determined 39 ophiopogonones and 71 ophiopogonins compounds in Sichuan and Zhejiang O. japonicas extracts and found the contents of these compositions have several times difference. Evidenced by experimental data of pharmacological activities in inhibiting cardiomyocyte damage induced by H2O2, mouse macrophage cell inflammation induced by lipopolysaccharide and cytotoxicity in vitro, Zhejiang O. japonicas extract had a stronger antioxidant and anti-inflammatory capacity than Sichuan O. japonicas extract, and the two O. japonicas extracts exhibited selective cytotoxicity on different cancer cell lines in vitro. These data shed light on the links between bioactive components and pharmacological activities of O. japonicas derived preparations. Thus, geographical origin of O. japonicas should be considered to be a key factor in efficacy studies and further clinical application.

[Update on immune and metabolic dysregulation in major depressive disorder and the implications for drug intervention].

Traditional anti-depressant therapy based on the regulation of monoamine neurotransmitters has shown certain limitations. Recently, accumulating clinical and preclinical studies have reported the tantalizing link between immune dysregulation, inflammatory process and the initiation and exacerbation of major depressive disorder (MDD). With a deepening understanding of neural-immune-metabolic interactions, an immunometabolism driven disease network has attracted huge interests in understanding neuronal inflammation and dysfunction underlying MDD pathogenesis and intervention. This review describes recent data uncovering immunometabolic dysregulation as a key factor in MDD network, with a focus on the recent appreciation of immune-metabolic actions of several anti-depressant compounds. The implications for the discovery of novel antidepressant drugs and clinical management of MDD are discussed.

Isochlorogenic acid A affects P450 and UGT enzymes in vitro and in vivo.

Isochlorogenic acid A (ICQA), which has anti-inflammatory, hepatoprotective, and antiviral properties, is commonly presented in fruits, vegetables, coffee, plant-based food products, and herbal medicines. These herbal medicines are usually used in combination with other medicines in the clinic. However, little is known about the regulatory effects of ICQA on drug-metabolizing enzymes and the herb-drug interactions. In the present study, we evaluated the inhibitory potentials of ICQA on CYP1A2, CYP2C9, CYP2C19, CYP3A4, CYP2D6, and CYP2E1 in vitro based on a cocktail approach. The P450 and UGT activities in mice treated with ICQA for a prolonged period were also determined. Our results demonstrated that ICQA exhibited a weak inhibitory effect on CYP2C9 in human liver microsomes with IC50 being 57.25 µmol·L-1 and Ki being 26.77 µmol·L-1. In addition, ICQA inhibited UGT1A6 activity by 25%, in the mice treated with ICQA (i.p.) at 30 mg·kg-1 for 14 d, compared with the control group. Moreover, ICQA showed no mechanism-based inhibition on CYP2C9 or UGT1A6. In conclusion, our results further confirm a safe use of ICQA in clinical practice.

NAMPT inhibition synergizes with NQO1-targeting agents in inducing apoptotic cell death in non-small cell lung cancer cells.

Nicotinamide phosphoribosyltransferase (NAMPT) catalyzes the first rate-limiting step in converting nicotinamide to NAD(+), essential for a number of enzymes and regulatory proteins involved in a variety of cellular processes, including deacetylation enzyme SIRT1 which modulates several tumor suppressors such as p53 and FOXO. Herein we report that NQO1 substrates Tanshione IIA (TSA) and ß-lapachone (ß-lap) induced a rapid depletion of NAD(+) pool but adaptively a significant upregulation of NAMPT. NAMPT inhibition by FK866 at a nontoxic dose significantly enhanced NQO1-targeting agent-induced apoptotic cell death. Compared with TSA or ß-lap treatment alone, co-treatment with FK866 induced a more dramatic depletion of NAD(+), repression of SIRT1 activity, and thereby the increased accumulation of acetylated FOXO1 and the activation of apoptotic pathway. In conclusion, the results from the present study support that NAMPT inhibition can synergize with NQO1 activation to induce apoptotic cell death, thereby providing a new rationale for the development of combinative therapeutic drugs in combating non-small lung cancer.

Effects of diammonium glycyrrhizinate on hepatic and intestinal UDP-Glucuronosyltransferases in rats: Implication in herb-drug interactions.

Glycyrrhizin is a major bioactive component of liquorice, which exerts multiple biochemical and pharmacological activities and is frequently used in combination with other drugs in the clinic. Mycophenolate mofetil (MMF), an immunosuppressant widely used in transplant patients, is metabolized by UDP-glucuronyltransferases (UGTs). Although significant evidence supports that glycyrrhizin could interact with the cytochrome P450s (CYPs), few studies have addressed its effects on UGTs. The present study aimed at investigating the regulatory effects of diammonium glycyrrhizinate (GLN) on UGTs in vitro and in vivo. We found that long-term administration of GLN in rats induced overall metabolism of MMF, which might be due to the induction of UGT1A protein expression. Hepatic UGT1A activity and UGT1A mRNA and protein expression were significantly increased in GLN-treated rats. UGT1A expression levels were also increased in the intestine, contradicting with the observed decrease in intestinal UGT1A activities. This phenomenon may be attributed to different concentrations of glycyrrhetinic acid (GA) in liver and intestine and the inhibitory effects of GA on UGT1A activity. In conclusion, our study revealed that GLN had multiple effects on the expression and activities of UGT1A isoforms, providing a basis for a better understanding of interactions between GLN and other drugs.

Pharmacodynamics and potential synergistic effects of Mai-Luo-Ning injection on cardiovascular protection, based on molecular docking.

As a computer-assisted approach, molecular docking has been universally applied in drug research and development and plays an important role in the investigation and evaluation of herbal medicines. Herein, the method was used to estimate the pharmacodynamics of Mai-Luo-Ning injection, a traditional Chinese compound herbal prescription. Through investigating the interactions between several important proteins in cardiovascular system and characteristic components of the formula, its effect on cardiovascular protection was evaluated. Results showed the differences in the interactions between each component and the selected target proteins and revealed the possible mechanisms for synergistic effects of various characteristic components on cardiovascular protection. The study provided scientific evidence supporting the mechanistic study of the interactions among multi-components and targets, offering a general approach to investigating the pharmacodynamics of complicated materials in compound herbal prescriptions.

[Progress in the role of farnesoid X receptor in metabolic regulation and tumor cell proliferation].

Farnesoid X receptor (FXR) is a ligand-activated transcriptional factor belonged to the superfamily of nuclear receptors. In the past decades, FXR has been found with important roles in the regulation of metabolic homeostasis of bile acids, cholesterol, lipids and carbohydrates. Recent studies further demonstrate the potential protective effect of FXR against metabolic diseases, such as hyperglycemia and hyperlipidemia, as well as inflammatory bowel diseases (IBD). In addition, FXR plays an essential role in liver regeneration, tumor cell proliferation and apoptosis. However, the role of FXR in the development of tumor is still obscure and even with discrepancy. This article reviews the function of FXR in metabolic regulation and recent progress in basic, clinical and pharmacological researches related to tumor cell proliferation involving FXR.

Bioactive equivalence of combinatorial components identified in screening of an herbal medicine.

PURPOSE: To identify bioactive equivalent combinatorial components (BECCs) in herbal medicines. The exact composition of effective components in herbal medicines is often elusive due to the lack of adequate screening methodology. Herein, we propose a hypothesis that BECCs accounting for the whole efficacy of original herbal medicines could be discovered from a complex mixture of constituents. METHODS: We developed a bioactive equivalence oriented feedback screening method and applied it to discover the BECCs from an herbal preparation Cardiotonic Pill (CP). The operations include chemical profiling of CP, followed by an iterative loop of determining, collecting and evaluating candidate BECCs. RESULTS: A combination of 18 compounds was identified as BECCs from CP, which accounts for 15.0% (w/w) of original CP. We have demonstrated that the BECCs were as effective as CP in cell models and in a rat model of myocardial infarction. CONCLUSIONS: This work answers the key question of which are real bioactive components for CP that have been used in clinic for many years, and provides a promising approach for discovering BECCs from herbal medicines. More importantly, the BECCs could be extended to improve quality control of herbal products and inspire an herbal medicines based discovery of combinatorial therapeutics.

A high-resolution peak fractionation approach for streamlined screening of nuclear-factor-E2-related factor-2 activators in Salvia miltiorrhiza.

Generation of a high-purity fraction library for efficiently screening active compounds from natural products is challenging because of their chemical diversity and complex matrices. In this work, a strategy combining high-resolution peak fractionation (HRPF) with a cell-based assay was proposed for target screening of bioactive constituents from natural products. In this approach, peak fractionation was conducted under chromatographic conditions optimized for high-resolution separation of the natural product extract. The HRPF approach was automatically performed according to the predefinition of certain peaks based on their retention times from a reference chromatographic profile. The corresponding HRPF database was collected with a parallel mass spectrometer to ensure purity and characterize the structures of compounds in the various fractions. Using this approach, a set of 75 peak fractions on the microgram scale was generated from 4mg of the extract of Salvia miltiorrhiza. After screening by an ARE-luciferase reporter gene assay, 20 diterpene quinones were selected and identified, and 16 of these compounds were reported to possess novel Nrf2 activation activity. Compared with conventional fixed-time interval fractionation, the HRPF approach could significantly improve the efficiency of bioactive compound discovery and facilitate the uncovering of minor active components.

Combined effects of a high-fat diet and chronic valproic acid treatment on hepatic steatosis and hepatotoxicity in rats.

AIM: To investigate the potential interactive effects of a high-fat diet (HFD) and valproic acid (VPA) on hepatic steatosis and hepatotoxicity in rats. METHODS: Male SD rats were orally administered VPA (100 or 500 mg·kg⁻¹·d⁻¹) combined with HFD or a standard diet for 8 weeks. Blood and liver samples were analyzed to determine lipid levels and hepatic function biomarkers using commercial kit assays. Low-molecular-weight compounds in serum, urine and bile samples were analyzed using a metabonomic approach based on GC/TOF-MS. RESULTS: HFD alone induced extensive hepatocyte steatosis and edema in rats, while VPA alone did not cause significant liver lesions. VPA significantly aggravated HFD-induced accumulation of liver lipids, and caused additional spotty or piecemeal necrosis, accompanied by moderate infiltration of inflammatory cells in the liver. Metabonomic analysis of serum, urine and bile samples revealed that HFD significantly increased the levels of amino acids, free fatty acids (FFAs) and 3-hydroxy-butanoic acid, whereas VPA markedly decreased the levels of amino acids, FFAs and the intermediate products of the tricarboxylic acid cycle (TCA) compared with the control group. HFD aggravated VPA-induced inhibition on lipid and amino acid metabolism. CONCLUSION: HFD magnifies VPA-induced impairment of mitochondrial ß-oxidation of FFAs and TCA, thereby increases hepatic steatosis and hepatotoxicity. The results suggest the patients receiving VPA treatment should be advised to avoid eating HFD.

Effect of root length on epicotyl dormancy release in seeds of Paeonia ludlowii, Tibetan peony.

BACKGROUND AND AIMS: Epicotyl dormancy break in seeds that have deep simple epicotyl morphophysiological dormancy (MPD) requires radicle emergence and even a certain root length in some species. However, the mechanisms by which root length affects epicotyl dormancy break are not clear at present. This study aims to explore the relationship between root length and epicotyl dormancy release in radicle-emerged seeds of Tibetan peony, Paeonia ludlowii, with discussion of the possible mechanisms. METHODS: Radicle-emerged seeds (radicle length 1.5, 3.0, 4.5 and 6.0 cm) were incubated at 5, 10 and 15 °C. During the stratification, some seeds were transferred to 15 °C and monitored for epicotyl-plumule growth. Hormone content was determined by ELISA, and the role of hormones in epicotyl dormancy release was tested by exogenous hormone and embryo culture. KEY RESULTS: Cold stratification did not break the epicotyl dormancy until the root length was ≥6 cm. The indole-3-actic acid (IAA) and GA3 contents of seeds having 6 cm roots were significantly higher than those of seeds with other root lengths, but the abscisic acid (ABA) content was lowest among radicle-emerged seeds. GA3 (400 mg L(-1)) could break epicotyl dormancy of all radicle-emerged seeds, while IAA (200 mg L(-1)) had little or no effect. When grown on MS medium, radicles of naked embryos grew and cotyledons turned green, but epicotyls did not elongate. Naked embryos developed into seedlings on a mixed medium of MS + 100 mg L(-1) GA3. CONCLUSIONS: A root length of ≥6.0 cm is necessary for epicotyl dormancy release by cold stratification. The underlying reason for root length affecting epicotyl dormancy release is a difference in the GA3/ABA ratio in the epicotyl within radicle-emerged seeds, which is mainly as a result of a difference in ABA accumulation before cold stratification.

The identification and pharmacokinetic studies of metabolites of salvianolic acid B after intravenous administration in rats.

AIM: To identify and quantify the major metabolites of salvianolic acid B (SAB) after intravenous injection in rats. METHODS: LC-IT/TOF-MS was used to identify the metabolites in rat bile, plasma, and urine; LC-MS/MS was used to quantify the two major metabolites. RESULTS: In rat bile, plasma, and urine, nine metabolites were identified, including methylated metabolites of SAB, lithospermic acid (LSA), the decarboxylation and methylation metabolites of LSA, salvianolic acid S (SAS), and dehydrated-SAS. The t1/2 of monomethyl-SAB and LSA were both very short, and monomethyl-SAB had a larger AUC than LSA in rats. CONCLUSION: Nine metabolites were found, the metabolic pathway was described, and the pharmacokinetic profiles of LSA and monomethyl-SAB were studied, thereby clarifying that methylation was the dominant metabolic pathway for SAB in rats.