TRIMETHYLAMINE OXIDE - FACTOR IN THE DEVELOPMENT OF ATHEROSCLEROSIS AND A POTENTIAL TARGET FOR DIETARY AND PHARMACOLOGICAL INTERVENTIONS.

Atherosclerotic Cardiovascular Diseases (ASCVD) are the most common cause of death worldwide. Among the well-known con¬tributors to atherosclerosis are less common ones, such as trimethylamine oxide (TMAO). This substance is formed from the oxida¬tion of trimethylamine (TMA) with the participation of flavin oxidases in the liver. TMA is produced with the involvement of the intestinal microbiota from foods rich in choline and carnitine. TMAO promotes the production of foam cells, enhances platelet aggregation, affects endothelial inflammation, and promotes atherosclerosis development. However, further research is needed to determine the effect of dietary changes on reducing TMAO levels and thus reducing incident ASCVD.

Gut-restricted apical sodium-dependent bile acid transporter inhibitor attenuates alcohol-induced liver steatosis and injury in mice.

BACKGROUND: Recent studies have shown that human and experimental alcohol-related liver disease (ALD) is robustly associated with dysregulation of bile acid homeostasis, which may in turn modulate disease severity. Pharmacological agents targeting bile acid metabolism and signaling may be potential therapeutics for ALD. METHODS: The potential beneficial effects of a gut-restricted apical sodium-dependent bile acid transporter (ASBT) inhibitor were studied in a chronic-plus-binge ALD mouse model. RESULTS: Blocking intestinal bile acid reabsorption by the gut-restricted ASBT inhibitor GSK2330672 attenuated hepatic steatosis and liver injury in a chronic-plus-binge ALD mouse model. Alcohol feeding is associated with intestinal bile acid accumulation but paradoxically impaired ileal farnesoid × receptor (FXR) function, and repressed hepatic cholesterol 7α-hydrolase (CYP7A1) expression despite decreased hepatic small heterodimer partner (SHP) and ileal fibroblast growth factor 15 (FGF15) expression. ASBT inhibitor treatment decreased intestinal bile acid accumulation and increased hepatic CYP7A1 expression, but further decreased ileal FXR activity. Alcohol feeding induces serum bile acid concentration that strongly correlates with a liver injury marker. However, alcohol-induced serum bile acid elevation is not due to intrahepatic bile acid accumulation but is strongly and positively associated with hepatic multidrug resistance-associated protein 3 (MRP4) and MRP4 induction but poorly associated with sodium-taurocholate cotransporting peptide (NTCP) expression. ASBT inhibitor treatment decreases serum bile acid concentration without affecting hepatocyte basolateral bile acid uptake and efflux transporters. CONCLUSION: ASBT inhibitor treatment corrects alcohol-induced bile acid dysregulation and attenuates liver injury in experimental ALD.

Gut Microbiota in Human Immunodeficiency Virus-Infected Individuals Linked to Coronary Heart Disease.

Background: Human immunodeficiency virus (HIV) infection is an independent risk factor for coronary heart disease (CHD) and is associated with perturbation of the gut microbiota. Methods: We analyzed gut microbiota in 30 HIV-infected individuals with CHD (CHD+) and 30 without CHD (CHD-) of the HIV-HEART study group. Results: Gut microbiota linked to CHD was associated with lower α-diversity. Despite insignificant differences in ß-diversity, co-occurrence networks of bacterial genera clearly diverged between CHD+ and CHD- individuals. Multidimensional scaling separated HIV-infected individuals into 2 microbiome clusters, dominated by the genus Prevotella or Bacteroides. The relative abundance of 49 other genera was significantly different between both clusters. The Prevotella-rich cluster was largely composed of men who have sex with men (MSM) (97%), whereas the Bacteroides-rich cluster comprised both MSM (45%) and heterosexual individuals (55%). MSM of the Bacteroides-rich cluster were characterized by reduced α-diversity, advanced immunological HIV stage, longer antiretroviral therapy with more ART regimens, and longer use of protease inhibitors, compared with Prevotella-rich MSM. Conclusions: Community structures of gut microbiota rather than individual species might facilitate risk assessment of CHD in HIV-infected individuals. Sexual behavior appears to be an important factor affecting gut microbiota ß-diversity and should be considered in future studies.

Activation of GPR40 produces mechanical antiallodynia via the spinal glial interleukin-10/ß-endorphin pathway.

BACKGROUND: The G protein-coupled receptor 40 (GPR40), broadly expressed in various tissues such as the spinal cord, exerts multiple physiological functions including pain regulation. This study aimed to elucidate the mechanisms underlying GPR40 activation-induced antinociception in neuropathic pain, particularly related to the spinal glial expression of IL-10 and subsequent ß-endorphin. METHODS: Spinal nerve ligation-induced neuropathic pain model was used in this study. ß-Endorphin and IL-10 levels were measured in the spinal cord and cultured primary microglia, astrocytes, and neurons. Double immunofluorescence staining of ß-endorphin with glial and neuronal cellular biomarkers was also detected in the spinal cord and cultured primary microglia, astrocytes, and neurons. RESULTS: GPR40 was expressed on microglia, astrocytes, and neurons in the spinal cords and upregulated by spinal nerve ligation. Intrathecal injection of the GPR40 agonist GW9508 dose-dependently attenuated mechanical allodynia and thermal hyperalgesia in neuropathic rats, with Emax values of 80% and 100% MPE and ED50 values of 6.7 and 5.4 µg, respectively. Its mechanical antiallodynia was blocked by the selective GPR40 antagonist GW1100 but not GPR120 antagonist AH7614. Intrathecal GW9508 significantly enhanced IL-10 and ß-endorphin immunostaining in spinal microglia and astrocytes but not in neurons. GW9508 also markedly stimulated gene and protein expression of IL-10 and ß-endorphin in cultured primary spinal microglia and astrocytes but not in neurons, originated from 1-day-old neonatal rats. The IL-10 antibody inhibited GW9508-stimulated gene expression of the ß-endorphin precursor proopiomelanocortin (POMC) but not IL-10, whereas the ß-endorphin antibody did not affect GW9508-stimulated IL-10 or POMC gene expression. GW9508 increased phosphorylation of mitogen-activated protein kinases (MAPKs) including p38, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK), and its stimulatory effects on IL-10 and POMC expression were blocked by each MAPK isoform inhibitor. Spinal GW9508-induced mechanical antiallodynia was completely blocked by intrathecal minocycline, IL-10 neutralizing antibody, ß-endorphin antiserum, and µ-opioid receptor-preferred antagonist naloxone. CONCLUSIONS: Our results illustrate that GPR40 activation produces antinociception via the spinal glial IL-10/ß-endorphin antinociceptive pathway.

Effects of two isometheptene enantiomers in isolated human blood vessels and rat middle meningeal artery - potential antimigraine efficacy.

BACKGROUND: Racemic isometheptene [(RS)-isometheptene] is an antimigraine drug that due to its cardiovascular side-effects was separated into its enantiomers, (R)- and (S)-isometheptene. This study set out to characterize the contribution of each enantiomer to its vasoactive profile. Moreover, rat neurogenic dural vasodilatation was used to explore their antimigraine mechanism of action. METHODS: Human blood vessel segments (middle meningeal artery, proximal and distal coronary arteries, and saphenous vein) were mounted in organ baths and concentration response curves to isometheptene were constructed. Calcitonin gene-related peptide (CGRP)-induced neurogenic dural vasodilation was elicited in the presence of the enantiomers using a rat closed cranial window model. RESULTS: The isometheptene enantiomers did not induce any significant contraction in human blood vessels, except in the middle meningeal artery, when they were administered at the highest concentration (100 µM). Interestingly in rats, (S)-isometheptene induced more pronounced vasopressor responses than (R)-isometheptene. However, none of these compounds affected the CGRP-induced vasodilator responses. CONCLUSION: The isometheptene enantiomers displayed a relatively safe peripheral vascular profile, as they failed to constrict the human coronary artery. These compounds do not appear to modulate neurogenic dural CGRP release, therefore, their antimigraine site of action remains to be determined.

Effect of ileal bile acid transporter inhibitor GSK2330672 on pruritus in primary biliary cholangitis: a double-blind, randomised, placebo-controlled, crossover, phase 2a study.

BACKGROUND: Up to 70% of patients with primary biliary cholangitis develop pruritus (itch) during the course of their disease. Treatment of pruritus in primary biliary cholangitis is challenging and novel therapies are needed. Ursodeoxycholic acid, the standard first-line treatment for primary biliary cholangitis, is largely ineffective for pruritus. We investigated the efficacy and safety of GSK2330672, a selective inhibitor of human ileal bile acid transporter (IBAT), in patients with primary biliary cholangitis with pruritus. METHODS: We conducted this phase 2a, double-blind, randomised, placebo-controlled, crossover trial in two UK medical centres. Following 2 weeks of open placebo run-in, patients were randomly assigned in a 1:1 ratio with a block size of 4 to receive GSK2330672 or placebo twice daily during two consecutive 14-day treatment periods in a crossover sequence. The treatment periods were followed by a 14-day single-blinded placebo follow-up period. The primary endpoints were safety of GSK2330672, assessed using clinical and laboratory parameters, and tolerability as rated by the Gastrointestinal Symptom Rating Scale. The secondary endpoints were changes in pruritus scores measured using the 0 to 10 numerical rating scale (NRS), primary biliary cholangitis-40 (PBC-40) itch domain score and 5-D itch scale, changes in serum total bile acids and 7 alpha hydroxy-4-cholesten-3-one (C4), and changes in the pharmacokinetic parameters of ursodeoxycholic acid and its conjugates. The trial was registered with ClinicalTrials.gov, number NCT01899703. FINDINGS: Between March 10, 2014, and Oct 7, 2015, we enrolled 22 patients. 11 patients were assigned to receive intervention followed by placebo (sequence 1), and 11 patients were assigned to receive placebo followed by intervention (sequence 2). One patient assigned to sequence 2 withdrew consent prior to receiving randomised therapy. One patient did not attend the placebo follow-up period, but was included in the final analysis. GSK2330672 treatment for 14 days was safe with no serious adverse events reported. Diarrhoea was the most frequent adverse event during treatment with GSK2330672 (seven with GSK2330672 vs one with placebo) and headache was the most frequent adverse event during treatment with placebo (seven with placebo vs six with GSK2330672). After GSK2330672 treatment, the percentage changes from baseline itch scores were -57% (95% CI -73 to -42, p<0·0001) in the NRS, -31% (-42 to -20, p<0·0001) in the PBC-40 itch domain and -35% (-45 to -25, p<0·0001) in the 5-D itch scale. GSK2330672 produced significantly greater reduction from baseline than the double-blind placebo in the NRS (-23%, 95% CI -45 to -1; p=0·037), PBC-40 itch domain, (-14%, -26 to -1; p=0·034), and 5-D itch scale (-20%, -34 to -7; p=0·0045). After GSK2330672 treatment, serum total bile acid concentrations declined by 50% (95% CI -37 to -61, p<0·0001) from 30 to 15 µM, with a significant 3·1-times increase (95% CI 2·4 to 4·0, p<0·0001) in serum C4 concentrations from 7·9 to 24·7ng/mL. INTERPRETATION: In patients with primary biliary cholangitis with pruritus, 14 days of ileal bile acid transporter inhibition by GSK2330672 was generally well tolerated without serious adverse events, and demonstrated efficacy in reducing pruritus severity. GSK2330672 has the potential to be a significant and novel advance for the treatment of pruritus in primary biliary cholangitis. Diarrhoea, the most common adverse event associated with GSK2330672 treatment, might limit the long-term use of this drug. FUNDING: GlaxoSmithKline and National Institute for Health Research.

Chronic, low-dose TMAO treatment reduces diastolic dysfunction and heart fibrosis in hypertensive rats.

Several studies have suggested negative effects of trimethylamine oxide (TMAO) on the circulatory system. However, a number of studies have shown protective functions of TMAO, a piezolyte and osmolyte, in animals exposed to high hydrostatic and/or osmotic stress. We evaluated the effects of TMAO treatment on the development of hypertension and its complications in male spontaneously hypertensive rats (SHRs) maintained on water (SHR-Water) and SHRs drinking TMAO water solution from weaning (SHR-TMAO). Wistar-Kyoto (WKY) rats were used as normotensive controls to discriminate between age-dependent and hypertension-dependent changes. Telemetry measurements of blood pressure were performed in rats between the 7th and 16th weeks of life. Anesthetized rats underwent echocardiographic, electrocardiographic, and direct left ventricular end-diastolic pressure (LVEDP) measurements. Hematoxylin and eosin as well as van Gieson staining for histopathological evaluation were performed. Plasma TMAO measured by chromatography coupled with mass spectrometry was significantly higher in the SHR-Water group compared with the WKY group (~20%). TMAO treatment increased plasma TMAO by four- to fivefold and did not affect the development of hypertension in SHRs. Sixteen-week-old rats in the SHR-Water and SHR-TMAO groups (12-wk TMAO treatment) showed similar blood pressures, angiopathy, and cardiac hypertrophy. However, the SHR-TMAO group had lower plasma NH2-terminal pro-B-type natriuretic peptide, LVEDP, and cardiac fibrosis. In contrast to age-matched WKY rats, 60-wk-old SHRs showed hypertensive angiopathy and heart failure with preserved ejection fraction. Compared with the SHR-Water group, the SHR-TMAO group (56-wk TMAO treatment) showed significantly lower plasma NH2-terminal pro-B-type natriuretic peptide and vasopressin, significantly lower LVEDP, and cardiac fibrosis. In conclusion, a four- to fivefold increase in plasma TMAO does not exert negative effects on the circulatory system. In contrast, increased dietary TMAO seems to reduce diastolic dysfunction in pressure-overloaded hearts in rats. NEW & NOTEWORTHY Chronic, low-dose trimethylamine oxide (TMAO) treatment that increases plasma TMAO by four- to fivefold reduces plasma NH2-terminal pro-B-type natriuretic peptide and vasopressin, left ventricular end-diastolic pressure, and cardiac fibrosis in pressure-overloaded hearts in hypertensive rats. Our study provides evidence that a moderate increase in plasma TMAO does not have a negative effect on the circulatory system. In contrast, increased dietary TMAO seems to reduce diastolic dysfunction in the pressure-overloaded heart.

Structure-based design of free fatty acid receptor 1 agonists bearing non-biphenyl scaffold.

The free fatty acid receptor 1 (FFA1) enhances the glucose-stimulated insulin secretion without the risk of hypoglycemia. However, most of FFA1 agonists have a common biphenyl moiety, leading to a relative deprivation in structure types. Herein, we describe the exploration of non-biphenyl scaffold based on the co-crystal structure of FFA1 to increase additional interactions with the lateral residues, which led to the identification of lead compounds 3 and 9. In induced-fit docking study, compound 3 forms an edge-on interaction with Trp150 by slightly rotating the indole ring of Trp150, and compound 9 has additional hydrogen bond and δ-π interactions with Leu135, which demonstrated the feasibility of our design strategy. Moreover, lead compounds 3 and 9 revealed improved polar surface area compared to GW9508, and have considerable hypoglycemic effects in mice. This structure-based study might inspire us to design more promising FFA1 agonists by increasing additional interactions with the residues outside of binding pocket.

Pharmacological analysis of the increases in heart rate and diastolic blood pressure produced by (S)-isometheptene and (R)-isometheptene in pithed rats.

BACKGROUND: Isometheptene is a sympathomimetic drug effective in acute migraine treatment. It is composed of two enantiomers with diverse pharmacological properties. This study investigated in pithed rats the cardiovascular effects of (S)- isometheptene and (R)-isometheptene, and the pharmacological profile of the more potent enantiomer. METHODS: The effects of i.v. bolus injections (0.03, 0.1, 0.3, 1 and 3 mg/kg) of isometheptene racemate, (S)-isometheptene or (R)-isometheptene on heart rate and blood pressure were analyzed in control experiments. The enantiomer producing more pronounced tachycardic and/or vasopressor responses was further analyzed in rats receiving i.v. injections of prazosin (0.1 mg/kg), rauwolscine (0.3 mg/kg), propranolol (1 mg/kg) or intraperitoneal reserpine (5 mg/kg, -24 h). RESULTS: Compared to (R)-isometheptene, (S)-isometheptene produced greater vasopressor responses, whilst both compounds equipotently increased heart rate. The tachycardic responses to (S)-isometheptene were abolished after propranolol, but remained unaffected by the other antagonists. In contrast, the vasopressor responses to (S)-isometheptene were practically abolished after prazosin. Interestingly, after reserpine, the tachycardic responses to (S)-isometheptene were abolished, whereas its vasopressor responses were attenuated and subsequently abolished by prazosin. CONCLUSIONS: The different cardiovascular effects of the isometheptene enantiomers are probably due to differences in their mechanism of action, namely: (i) a mixed sympathomimetic action for (S)-isometheptene (a tyramine-like action and a direct stimulation of α1-adrenoceptors); and (ii) exclusively a tyramine like action for (R)-isometheptene. Thus, (R)-isometheptene may represent a superior therapeutic benefit as an antimigraine agent.

BAT117213: Ileal bile acid transporter (IBAT) inhibition as a treatment for pruritus in primary biliary cirrhosis: study protocol for a randomised controlled trial.

BACKGROUND: Pruritus (itch) is a symptom commonly experienced by patients with cholestatic liver diseases such as primary biliary cholangitis (PBC, previously referred to as primary biliary cirrhosis). Bile acids (BAs) have been proposed as potential pruritogens in PBC. The ileal bile acid transporter (IBAT) protein expressed in the distal ileum plays a key role in the enterohepatic circulation of BAs. Pharmacological inhibition of IBAT with GSK2330672 may reduce BA levels in the systemic circulation and improve pruritus. METHODS: This clinical study (BAT117213 study) is sponsored by GlaxoSmithKline (GSK) with associated exploratory studies supported by the National Institute for Health Research (NIHR). It is a phase 2a, multi-centre, randomised, double bind, placebo controlled, cross-over trial for PBC patients with pruritus. The primary objective is to investigate the safety and tolerability of repeat doses of GSK2330672, and explore whether GSK2330672 administration for 14 days improves pruritus compared with placebo. The key outcomes include improvement in pruritus scores evaluated on a numerical rating scale and other PBC symptoms in an electronic diary completed twice daily by the patients. The secondary outcomes include the evaluation of the effect of GSK2330672 on total serum bile acid (BA) concentrations, serum markers of BA synthesis and steady-state pharmacokinetics of ursodeoxycholic acid (UDCA). DISCUSSION: BAT117213 study is the first randomised controlled crossover trial of ileal bile acid transporter inhibitor, a novel class of drug to treat pruritus in PBC. The main strengths of the trial are utility of a novel, study specific, electronic symptom diary as patient reported outcome to measure the treatment response objectively and the crossover design that allows estimating the treatment effect in a smaller number of patients. The outcome of this trial will inform the trial design of future development phase of the IBAT inhibitor drug. The trial will also provide opportunity to conduct metabonomic and gut microbiome studies as explorative and mechanistic research in patients with cholestatic pruritus. TRIAL REGISTRATION: EudraCT number: 2012-005531-84, ClinicalTrials.gov Identifier: NCT01899703 , registered on 3(rd) July 2013.

Activation of free fatty acid receptors, FFAR1 and FFAR4, ameliorates ulcerative colitis by promote fatty acid metabolism and mediate macrophage polarization.

OBJECTIVE: To investigate the mechanism of action of fatty acid receptors, FFAR1 and FFAR4, on ulcerative colitis (UC) through fatty acid metabolism and macrophage polarization. METHODS: Dextran sulfate sodium (DSS)-induced mouse model of UC mice was used to evaluate the efficacy of FFAR1 (GW9508) and FFAR4 (GSK137647) agonists by analyzing body weight, colon length, disease activity index (DAI), and histological scores. Real-time PCR and immunofluorescence analysis were performed to quantify the levels of fatty acid metabolizing enzymes and macrophage makers. FFA-induced lipid accumulation in RAW264.7 cells was visualized by Oil Red O staining analysis, and cells were collected to detect macrophage polarization by flow cytometry. RESULTS: The combination of GW9508 and GSK137647 significantly improved DSS-induced UC symptoms, caused recovery in colon length, and decreased histological injury. GW9508 + GSK137647 treatment upregulated the expressions of CD206, lipid oxidation enzyme (CPT-1α) and anti-inflammatory cytokines (IL-4, IL-10, IL-13) but downregulated those of CD86, lipogenic enzymes (ACC1, FASN, SCD1), and pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α). Combining the two agonists decreased FFA-induced lipid accumulation and increased CD206 expression in cell-based experiments. CONCLUSION: Activated FFAR1 and FFAR4 ameliorates DSS-induced UC by promoting fatty acid metabolism to reduce lipid accumulation and mediate M2 macrophage polarization.

Multiple mechanisms of GW-9508, a selective G protein-coupled receptor 40 agonist, in the regulation of glucose homeostasis and insulin sensitivity.

Activation of G protein-coupled receptor 40 (GPR40) by agonists increases insulin release in isolated islets, whereas it is inconclusive whether GPR40 antagonists decrease blood glucose and increase insulin sensitivity. Although some clinical trials indicated that administration of a GPR40 agonist shows benefits in the regulation of blood glucose homeostasis, the pharmacological mechanisms of this receptor in the improvement of glycemic control remain unclear. Therefore, we used a selective GPR40 agonist, GW-9508, to clarify the role of GPR40 in the regulation of blood glucose. Bolus intraperitoneal injection of GW-9508 in mice showed a slight decrease in blood glucose, with an increase in plasma insulin levels under glucose stimuli. However, long-term treatment with low doses of GW-9508 in high-fat diet-induced (HFD) diabetic mice decreased blood glucose with decreased plasma insulin significantly and improved glucose intolerance and insulin resistance. Using small interfering ribonucleic acid to delete GPR40 in HepG2 cells, we demonstrated that GW-9508 reversed palmitate-induced insulin signaling impairment through a GPR40-dependent pathway. We also found that GW-9508 activates the Akt/GSK-3ß pathway to increase glycogen levels in HepG2 cells. Furthermore, administration of GW-9508 decreased the hepatic expression of fetuin-A in HFD mice significantly and regulated high-glucose- or palmitate-induced fetuin-A expression to increase insulin sensitivity through a GPR40/PLC/PKC pathway in HepG2 cells. Taken together, GW-9508 exerts a partial agonist effect to regulate blood glucose through multiple mechanisms. Investigation of chemicals that act on GPR40 might be a new strategy for the treatment of diabetes.

A novel MDMA analogue, UWA-101, that lacks psychoactivity and cytotoxicity, enhances L-DOPA benefit in parkinsonian primates.

Treatment of Parkinson's disease with dopaminergic agents, such as l-DOPA, is frequently compromised by disabling side effects, particularly dyskinesia and a shortening in duration of antiparkinsonian action. Studies in animal models and anecdotal evidence from a patient with Parkinson's disease show that the illicit drug ecstasy (MDMA) can alleviate these side effects, though with many drawbacks (e.g., psychoactivity). MDMA itself thus has little therapeutic potential. On the basis of known structure-psychoactivity relationships, we designed a series of α-substituted MDMA analogues, one of which, bearing an α-cyclopropyl substituent (UWA-101), enhanced the quality of l-DOPA actions in animal models. Indeed, UWA-101 was more effective than MDMA. Unlike MDMA, UWA-101 did not reduce viability of serotonergic cells, exhibit psychoactive properties, or reduce food intake, and did not substitute for MDMA in drug discrimination assays. UWA-101 displayed a unique receptor/transporter binding profile relative to MDMA, with a >5-fold decrease in affinity for NET and 5-HT(2A) receptors and a 10-fold increase in affinity for DAT. Furthermore, in a functional reuptake assay, UWA-101 inhibited both 5-HT and dopamine reuptake, while having no effect on the reuptake of noradrenaline. UWA-101 is the first selective DAT/SERT inhibitor described with comparable affinities for these two sites. These data identify a new class of therapeutic in Parkinson's disease and highlight the potential benefits of studying illicit drugs that in themselves would never be considered safe for long-term therapy.

Novel azulene derivatives for the treatment of erectile dysfunction.

Based on the dopamine D(4) receptor partial agonist FAUC 3019, a series of azulenylmethylpiperazines was synthesized and affinities for the monoaminergic GPCRs including dopamine, serotonin, histamine and α-adrenergic receptor subtypes were determined. Ligand efficacies of the most promising test compounds revealed the N,N-dimethylaminomethyl substituted azulene 11 to be the most potent D(4) partial agonist (EC(50)=0.41 nM). This candidate was investigated for its ability to promote penile erection. Applying an in vivo animal model, test compound 11 turned out to stimulate penile erection in male rats with superior potency in low concentrations when compared to apomorphine.

The Gut Axis Involvement in Heart Failure: Focus on Trimethylamine N-oxide.

A novel pathophysiological model of interest is the association between heart failure (HF) and the gastrointestinal system, the 'gut hypothesis'. The choline and carnitine metabolic by-product, Trimethylamine N-oxide (TMAO) is one of the more prominent molecules associated with the link between HF and the gut. Indeed, TMAO levels are increased in HF populations and higher TMAO levels are associated with poor prognosis, whereas low TMAO levels either at baseline/follow up confer better prognosis. Considering that TMAO levels seem not to be affected by guideline-HF treatment, this model could represent a novel and independent therapeutic target for HF.

Indatraline: synthesis and effect on the motor activity of Wistar rats.

A new approach for the synthesis of indatraline was developed using as the key step an iodine(III)-mediated ring contraction of a 1,2-dihydronaphthalene derivative. Behavioral tests were conducted to evaluate the effect of indatraline and of its precursor indanamide on the motor activity of Wistar rats. Specific indexes for ambulation, raising and stereotypy were computed one, two and three hours after i.p. drug administration. Indatraline effects on motor activity lasted for at least three hours. On the other hand, no significant differences in motor activity were observed using indanamide. The results suggest that indatraline has a long lasting effect on motor activity and add evidence in favor of the potential use of that compound as a substitute in cocaine addiction.

Implication of Gut Microbiota in Cardiovascular Diseases.

Emerging evidence has identified the association between gut microbiota and various diseases, including cardiovascular diseases (CVDs). Altered intestinal flora composition has been described in detail in CVDs, such as hypertension, atherosclerosis, myocardial infarction, heart failure, and arrhythmia. In contrast, the importance of fermentation metabolites, such as trimethylamine N-oxide (TMAO), short-chain fatty acids (SCFAs), and secondary bile acid (BA), has also been implicated in CVD development, prevention, treatment, and prognosis. The potential mechanisms are conventionally thought to involve immune regulation, host energy metabolism, and oxidative stress. However, numerous types of programmed cell death, including apoptosis, autophagy, pyroptosis, ferroptosis, and clockophagy, also serve as a key link in microbiome-host cross talk. In this review, we introduced and summarized the results from recent studies dealing with the relationship between gut microbiota and cardiac disorders, highlighting the role of programmed cell death. We hope to shed light on microbiota-targeted therapeutic strategies in CVD management.

GW9508 ameliorates cognitive impairment via the cAMP-CREB and JNK pathways in APPswe/PS1dE9 mouse model of Alzheimer's disease.

GPR40 was utilized as the drug target to the treatment of diabetes, but the function and mechanisms ameliorating the Alzheimer's disease (AD) remain unknown. In present study, the typical APP/PS1 mouse model was applied to explore the function and mechanism of GPR40 in AD. GPR40 agonist GW9508 and antagonist GW1100 were respectively given by i.c.v. injection to activate/inhibit the GPR40 in the brain of APP/PS1 mice which illustrated the function and mechanism of GPR40 in ameliorating AD symptoms. Morris water maze test, step-through test, Y-maze spontaneous alternation test, open field test and new object recognition test were used to test the cognitive function and memory ability of mice, while molecular biology experiments such as Western blot, immunofluorescence, JC-1 were used to detect the corresponding changes of signal pathways. The results revealed that treatment with GW9508 could significantly ameliorate cognitive deficits of APP/PS1 mice, upregulate the expression levels of cAMP, p-CREB and neurotrophic factors in vivo, while GW9508 also ameliorate Aß1-42-induced neuron damage and downregulate the expression levels of pathological protein such as p-JNK, JNK and apoptosis-related proteins such as IL-6, IL-1ß, TNF-α and caspase-3 in vitro. Meanwhile, high-content screening also showed that GW9508 promoted the cellular differentiation of SH-SY5Y cells, while GW1100 reversed the effects of GW9508. These results suggested that GPR40 was an underlying therapeutic target for the treatment of AD and GPR40 agonist could be explored as the emerging AD therapeutic drug.

Agonism of GPR120 prevented IL-1ß-induced reduction of extracellular matrix through SOX-9.

Osteoarthritis (OA) is a whole-joint disease with extremely high prevalence. In all treatment approaches of OA, blocking the degradation of the cartilage extracellular matrix is an important treatment. In OA, overexpression of derivative enzymes leads to excessive catabolism and reduced synthesis of cartilage including type II collagen and aggrecan, which results in irreversible destruction of the joint. SOX9 is a transcription factor that regulates the synthesis of type II collagen and aggrecan and is significantly downregulated in OA. GPR120 has been reported to affect the pathophysiology of OA. In this study, we used the GPR120 agonist GW9508 and TUG891 in ATDC5 chondrocytes exposed to interleukin (IL)-1ß to investigate the involvement of GPR120 in SOX9-mediated expression of type II collagen and aggrecan. Our findings show that agonism of GPR120 can reduce inflammation by inhibiting the expression of IL-6 and IL-8 induced by IL-1ß. We also show that GW9508 and TUG891 rescue the expression of type II collagen and aggrecan by preventing the reduction of SOX9 expression. Additionally, we demonstrate that the effects of GW9508 on SOX9 expression are mediated through CREB and that GPR120 is indeed required for this effect. Thus, agonism of GPR120 by GW9508 might be a potential therapeutic strategy to halt or prevent cartilage degradation.