Arachidyl amido cholanoic acid improves liver glucose and lipid homeostasis in nonalcoholic steatohepatitis via AMPK and mTOR regulation

BACKGROUND Arachidyl amido cholanoic acid(Aramchol) is a potent downregulator of hepatic stearoyl-CoA desaturase 1(SCD1) protein expression that reduces liver triglycerides and fibrosis in animal models of steatohepatitis. In a phase IIb clinical trial in patients with nonalcoholic steatohepatitis(NASH), 52 wk of treatment with Aramchol reduced blood levels of glycated hemoglobin A1c, an indicator of glycemic control.AIM To assess lipid and glucose metabolism in mouse hepatocytes and in a NASH mouse model [induced with a 0.1% methionine and choline deficient diet(0.1 MCD)] after treatment with Aramchol.METHODS Isolated primary mouse hepatocytes were incubated with 20 μmol/L Aramchol or vehicle for 48 h. Subsequently, analyses were performed including Western blot, proteomics by mass spectrometry, and fluxomic analysis with ~(13)C-uniformly labeled glucose. For the in vivo part of the study, male C57 BL/6 J mice were randomly fed a control or 0.1 MCD for 4 wk and received 1 or 5 mg/kg/d Aramchol or vehicle by intragastric gavage for the last 2 wk. Liver metabolomics were assessed using ultra-high-performance liquid chromatography-time of flight-MS for the determination of glucose metabolism-related metabolites.RESULTS Combination of proteomics and Western blot analyses showed increased AMPK activity while the activity of nutrient sensor mTORC1 was decreased by Aramchol in hepatocytes. This translated into changes in the content of their downstream targets including proteins involved in fatty acid(FA) synthesis and oxidation [PACCα/β(S79), SCD1, CPT1A/B, HADHA, and HADHB], oxidative phosphorylation(NDUFA9, NDUFB11, NDUFS1, NDUFV1, ETFDH, and UQCRC2), tricarboxylic acid(TCA) cycle(MDH2, SUCLA2, and SUCLG2), and ribosome(P-p70S6K[T389] and P-S6[S235/S236]). Flux experiments with ~(13)C uniformely labeled glucose showed that TCA cycle cataplerosis was reduced by Aramchol in hepatocytes, as indicated by the increase in the number of rounds that malate remained in the TCA cycle. Finally, liver metabolomic analysis showed that glucose homeostasis was improved by Aramchol in 0.1 MCD fed mice in a dose-dependent manner, showing normalization of glucose, G6P, F6P, UDP-glucose, and Rbl5 P/Xyl5 P.CONCLUSION Aramchol exerts its effect on glucose and lipid metabolism in NASH through activation of AMPK and inhibition of mTORC1, which in turn activate FA β-oxidation and oxidative phosphorylation.     

One-Year Follow-up of Duodenal Ulcers after 1-Wk Triple Therapy for Helicobacter pylori

Objective : to study the ulcer recurrence rate of Helicobacter pylori-positive duodenal ulcers at 1 yr after eradication of the bacteria by triple therapy. Method : Patients with H. pylori-positive duodenal ulcers were randomized to receive either triple therapy for 1 wk plus omeprazole for 4 wk (THple+OMP) (n = 78), or omeprazole alone (OMP) for 4 wk (N = 77). Patients were followed up every 3 months for symptom enquiry. At 1 yr, all asymptomatic patients were invited to attend for gastroscopy. Results : At 8 wk, 16 patients in the OMP group and four in the Triple+OMP group had an ulcer. During the 1-yr period, 12 patients in the OMP group and no patient in the Triple+OMP group developed symptomatic ulcers. At follow-up endoscopy at 1 yr, another 10 ulcers were detected in the OMP group and two in the Triple+OMP group. Fifteen patients in the OMP group and 13 in the Triple+OMP group were lost to follow-up. In total, ulcers were de-tected in 39 of 61 (64%) assessahle patients in the OMP group, and in six of 65 (97o) assessahle patients in the Triple+OMP group after I yr (χ² test: p < 0.001). Of the patients whose H, pytori were successfully eradicated hy Triple+OMP at 8 wk, 90% remained H. pylori negative at 1 yr. Conclusion : Triple therapy for 1 wk eradicates H, pylori infection and significantly reduces duodenal ulcer relapses.     

Rat Imaging and In Vivo Stability Studies using [11C]-Dimethyl-Diphenyl Ammonium,a Candidate Agent for PET-Myocardial Perfusion Imaging

BackgroundPET myocardial perfusion imaging (MPI) holds several advantages over SPECT for diagnosing coronary artery disease. The short half-lives of prevailing PET-MPI agents hamper wider clinical application of PET in nuclear cardiology; prompting the development of novel PET-MPI agents. We have previously reported on the potential of radiolabeled ammonium salts, and particularly on that of [¹¹C]dimethyl-diphenyl-ammonium ([¹¹C]DMDPA), for cardiac PET imaging. This study was designed to improve the radiosynthesis and increase the yield of [¹¹C]DMDPA, characterize more meticulously the kinetics of radioactivity distribution after its injection via micro-PET/CT studies, and further explore its potential for PET-MPI.MethodsThe radiosynthetic procedure of [¹¹C]DMDPA was improved with respect to the previously reported one. The kinetics of radioactivity distribution following injection of [¹¹C]DMDPA were investigated in juvenile and young adult male SD rats using microPET/CT, and compared to those of [¹³N]NH₃. Furthermore, the metabolic fate of [¹¹C]DMDPA in vivo was examined after its injection into rats.ResultsFollowing a radiosynthesis time of 25–27 min, 11.9 ± 1.1 GBq of [¹¹C]DMDPA was obtained, with a 43.7% ± 4.3% radiochemical yield (n = 7). Time activity curves calculated after administration of [¹¹C]DMDPA indicated rapid, high and sustained radioactivity uptake in hearts of both juvenile and young adult rats, having a two-fold higher cardiac radioactivity uptake compared to [¹³N]NH₃. Accordingly, at all time points after injection to both juvenile and young adult rats, image quality of the left ventricle was higher with [¹¹C]DMDPA compared to [¹³N]NH₃. In vivo stability studies of [¹¹C]DMDPA indicate that no radioactive metabolites could be detected in plasma, liver and urine samples of rats up to 20 min after injection, suggesting that [¹¹C]DMDPA is metabolically stable in vivo.ConclusionsThis study further illustrates that [¹¹C]DMDPA holds, at least in part, essential qualities required from a PET-MPI probe. Owing to the improved radiosynthetic procedure reported herein, [¹¹C]DMDPA can be produced in sufficient amounts for clinical use.     

Genetic variability of wild-type measles viruses, circulating in the Russian Federation during the implementation of the National Measles Elimination Program, 2003–2007

Genetic characterization of wild-type measles viruses (MVs) is an important component of laboratory surveillance of measles. In this study, a phylogenetic analysis was performed of the nucleoprotein gene sequences of 228 MVs isolated in the Russian Federation between 2003 and 2007. Five genotypes, D4, D5, D6, D8, and H1, were detected. From 1999 through the first 6 months of 2003, the most prevalent genotype in the European part of Russia was D4. All genotype D4-type viruses were closely related to each other (with overall sequence diversity of ≤0.9%), suggesting the presence of a single endemic MV strain. After 2003, viruses with closely related sequences within genotype D6 (≤0.9% sequence diversity) were prevalent. During this time, there was a low level of indigenous transmission of genotype D6, and genotype D6 viruses were imported from neighbouring countries, which led to the identification of two lineages of genotype D6, i.e. D6a and D6b. Lineage D6a was closely related to viruses isolated in Turkey, Kazakhstan, and Uzbekistan, whereas lineage D6b was linked to a large outbreak in Ukraine in 2005–2006. Genotypes H1, D5 and D8 were associated with sporadic cases and clusters of transmission linked to importations. Enhanced vaccination interrupted the transmission of the previous endemic lineage D4 in 2003 and of lineage D6a in 2005, although an accumulation of susceptible individuals in the population allowed for prolonged circulation of lineage D6b. These data on MV genotype distribution, in conjunction with the epidemiological data for measles, show considerable progress in measles control and suggest that regional elimination is possible.     

Efficacy of nimodipine in the prophylaxis of migraine

The efficacy of nimodipine in the prophylaxis of migraine was assessed in a double-blind, placebo-controlled, cross-over study carried out on 33 patients, 20 of whom suffered from classic and 13 from common migraine. Four patients dropped out, but not as a result of the side effects of the drug. The duration of drug treatment was 8 weeks. The dosage used was 30 mg four times daily. Nimodipine proved to be better than placebo, the number of migraine attacks and severity of headache showing a significant reduction. The drug was well tolerated and no marked side effects were noted. The results suggest that nimodipine is a useful new prophylactic drug for migraine, but further studies are needed before its final value can be evaluated.