Amlodipine is a commonly prescribed calcium channel blocker for the treatment of hypertension and ischemic heart disease. The drug is slowly cleared in humans primarily via dehydrogenation of its dihydropyridine moiety to a pyridine derivative (M9). Results from clinical drug-drug interaction studies suggest that CYP3A4/5 mediate metabolism of amlodipine. However, attempts to identify a role of CYP3A5 in amlodipine metabolism in humans based on its pharmacokinetic differences between CYP3A5 expressers and nonexpressers failed. Objectives of this study were to determine the metabolite profile of amlodipine (a racemic mixture and S-isomer) in human liver microsomes (HLM), and to identify the cytochrome P450 (P450) enzyme(s) involved in the M9 formation. Liquid chromatography/mass spectrometry analysis showed that amlodipine was mainly converted to M9 in HLM incubation. M9 underwent further O-demethylation, O-dealkylation, and oxidative deamination to various pyridine derivatives. This observation is consistent with amlodipine metabolism in humans. Incubations of amlodipine with HLM in the presence of selective P450 inhibitors showed that both ketoconazole (an inhibitor of CYP3A4/5) and CYP3cide (an inhibitor of CYP3A4) completely blocked the M9 formation, whereas chemical inhibitors of other P450 enzymes had little effect. Furthermore, metabolism of amlodipine in expressed human P450 enzymes showed that only CYP3A4 had significant activity in amlodipine dehydrogenation. Metabolite profiles and P450 reaction phenotyping data of a racemic mixture and S-isomer of amlodipine were very similar. The results from this study suggest that CYP3A4, rather than CYP3A5, plays a key role in metabolic clearance of amlodipine in humans.

Background: Poor habits can worsen gastroesophageal reflux disease (GERD) and reduce treatment efficacy. Few large-scale studies have examined lifestyle influences, particularly eating habits, on GERD in China, and research related to eating quickly, hyperphagia, and eating hot foods is quite limited. The aim of this study was to evaluate the relationship between GERD pathogenesis and lifestyle factors to produce useful information for the development of a clinical reference guide through a national multicenter survey in China. Methods: Symptom and lifestyle/habit questionnaires included 19 items were designed. The questionnaire results were subjected to correlation analysis relative to GERD symptom onset. A standard proton pump inhibitor (PPI) was advised to correct patients with unhealthful lifestyle habits. Results: A total of 1518 subjects (832 GERD, 686 non-GERD) enrolled from six Chinese hospitals completed symptom and lifestyle/habit questionnaires. The top lifestyle factors related to GERD were fast eating, eating beyond fullness, and preference for spicy food. Univariate analysis showed that 21 factors, including male gender, a supra-normal body mass index (BMI), smoking, drinking alcohol, fast eating, eating beyond fullness, eating very hot foods, and drinking soup, among others, were associated with GERD ( p < 0.05). Logistic multivariate regression analysis revealed the following risk factors for GERD [with odds ratios (ORs)]: fast eating (4.058), eating beyond fullness (2.849), wearing girdles or corsets (2.187), eating very hot foods (1.811), high BMI (1.805), lying down soon after eating (1.544), and smoking (1.521). Adjuvant lifestyle interventions improved outcomes over medication alone ( z = –8.578, p < 0.001 Mann–Whitney rank sum test). Conclusions: Lifestyle interventions can improve medication efficacy in GERD patients. Numerous habits, including fast eating, eating beyond fullness, and eating very hot foods, were associated with GERD pathogenesis. The present results may be useful as a reference for preventive education and treatment.

BackgroundEndocrine FGF19 and FGF21 exert their effects on metabolic homeostasis through fibroblast growth factor receptor (FGFR) and co-factor betaKlotho (KLB). Ileal FGF19 regulates bile acid metabolism through specifically FGFR4-KLB in hepatocytes where FGFR1 is not significant. Both FGF19 and FGF21 activate FGFR1-KLB whose function predominates in adipocytes. Recent studies using administration of FGF19 and FGF21 and genetic ablation of KLB or adipocyte FGFR1 indicate that FGFR1-KLB mediates the response of adipocytes to both FGF21 and FGF19. Here we show that adipose FGFR1 regulates lipid metabolism through direct effect on adipose tissue and indirect effects on liver under starvation conditions that cause hepatic stress.MethodsWe employed adipocyte-specific ablations of FGFR1 and FGFR2 genes in mice, and analyzed metabolic consequences in adipose tissue, liver and systemic parameters under normal, fasting and starvation conditions.ResultsUnder normal conditions, the ablation of adipose FGFR1 had little effect on adipocytes, but caused shifts in expression of hepatic genes involved in lipid metabolism. Starvation conditions precipitated a concurrent elevation of serum triglycerides and non-esterified fatty acids, and increased hepatic steatosis and adipose lipolysis in the FGFR1-deficient mice. Little effect on glucose or ketone bodies due to the FGFR1 deficiency was observed.ConclusionsOur results suggest an adipocyte-hepatocyte communication network mediated by adipocyte FGFR1 that concurrently dampens hepatic lipogenesis and adipocyte lipolysis. We propose that this serves overall to mete out and extend lipid reserves for neural fuels (glucose and ketone bodies), while at the same time governing extent of hepatosteatosis during metabolic extremes and other conditions causing hepatic stress.

Background:Parkinson's disease (PD) patients with long-term levodopa (L-DOPA) treatment are suffering from severe circadian dysfunction. However, it is hard to distinguish that the circadian disturbance in patients is due to the disease progression itself, or is affected by L-DOPA replacement therapy. This study was to investigate the role of L-DOPA on the circadian dysfunction in a rat model of PD.Methods:The rat model of PD was constructed by a bilateral striatal injection with 6-hydroxydopamine (6-OHDA), followed by administration of saline or 25 mg/kg L-DOPA for 21 consecutive days. Rotarod test, footprint test, and open-field test were carried out to evaluate the motor function. Striatum, suprachiasmatic nucleus (SCN), liver, and plasma were collected at 6:00, 12:00, 18:00, and 24:00. Quantitative real-time polymerase chain reaction was used to examine the expression of clock genes. Enzyme-linked immunosorbent assay was used to determine the secretion level of cortisol and melatonin. High-performance liquid chromatography was used to measure the neurotransmitters. Analysis of variance was used for data analysis.Results:L-DOPA alleviated the motor deficits induced by 6-OHDA lesions in the footprint and open-field test (P < 0.01, P < 0.001, respectively). After L-DOPA treatment, Bmal1 decreased in the SCN compared with 6-OHDA group at 12:00 (P < 0.01) and 24:00 (P < 0.001). In the striatum, the expression of Bmal1, Rorα was lower than that in the 6-OHDA group at 18:00 (P < 0.05) and L-DOPA seemed to delay the peak of Per2 to 24:00. In liver, L-DOPA did not affect the rhythmicity and expression of these clock genes (P > 0.05). In addition, the cortisol secretion was increased (P > 0.05), but melatonin was further inhibited after L-DOPA treatment at 6:00 (P < 0.01).Conclusions:In the circadian system of advanced PD rat models, circadian dysfunction is not only contributed by the degeneration of the disease itself but also long-term L-DOPA therapy may further aggravate it.

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Background Acute lung injury (ALI), which is induced by numerous pathogenic factors, especially sepsis, can generate alveolar damage, pulmonary edema and vascular hyper-permeability ultimately leading to severe hypoxemia. Fibroblast growth factor-2 (FGF2) is an important member of the FGF family associated with endothelial cell migration and proliferation, and injury repairment. Here, we conducted this study aiming to evaluate the therapeutic effect of FGF2 in sepsis-induced ALI. Methods Recombinant FGF2 was abdominally injected into septic mice induced by cecal ligation and puncture (CLP), and then the inflammatory factors of lung tissue, vascular permeability and lung injury-related indicators based on protein levels and gene expression were detected. In vitro, human pulmonary microvascular endothelial cells (HPMEC) and mouse peritoneal macrophages (PMs) were challenged by lipopolysaccharides (LPS) with or without FGF2 administration in different groups, and then changes in inflammation indicators and cell permeability ability were tested. Results The results revealed that FGF2 treatment reduced inflammation response, attenuated pulmonary capillary leakage, alleviated lung injury and improved survival in septic mice. The endothelial injury and macrophages inflammation induced by LPS were inhibited by FGF2 administration via AKT/P38/NF-κB signaling pathways. Conclusion These findings indicated a therapeutic role of FGF2 in ALI through ameliorating capillary leakage and inflammation.

Hydrogen sulfide (H2S) is a novel gaseous transmitter, regulating a multitude of biological processes in the cardiovascular and other systems. However, it remains unclear whether it exerts any effect on arterial thrombosis. In this study, we examined the effect of H2S on ferric chloride (FeCl3)-induced thrombosis in the rat common carotid artery (CCA). The results revealed a decrease of the H2S-producing enzyme cystathionine γ-lyase (CSE) expression and H2S production that persisted until 48 h after FeCl3 application. Intriguingly, administration with NaHS at appropriate regimen reduced the thrombus formation and enhanced the blood flow, accompanied with the alleviation of CSE and CD31 downregulation, and endothelial cell apoptosis in the rat CCA following FeCl3 application. Moreover, the antithrombotic effect of H2S was also observed in Rose Bengal photochemical model in which the development of thrombosis is contributed by oxidative injury to the endothelium. The in vitro study demonstrated that the mRNA and protein expression of CSE, as well as H2S production, was decreased in hydrogen peroxide (H2O2)-treated endothelial cells. Exogenous supplement of NaHS and CSE overexpression consistently alleviated the increase of cleaved caspase-3 and endothelial cell damage caused by H2O2. Taken together, our findings suggest that endogenous H2S generation in the endothelium may be impaired during arterial thrombosis and that modulation of H2S, either exogenous supplement or boost of endogenous production, may become a potential venue for arterial thrombosis therapy.

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