The antidiabetic effect of L-carnitine in rats: the role of nitric oxide system

Background: Nowadays, the use of L-carnitine in the treatment of diabetes is increasing. This study was conducted to investigate the effect of co-administration of L-arginine (precursor for the synthesis of nitric oxide) and nitro-L-arginine (nitric oxide synthesis inhibitor) on antidiabetic activity of L-carnitine in diabetic rats. Materials and Methods: In this study, 50 male rats weighing 180-201g were divided into five groups: (1) non diabetic control rats; (2) untreated diabetic rats; (3) diabetic rats treated with L-carnitine 300 mg/kg (4); diabetic rats treated with L-carnitine 300 mg/kg + L-arginine 300 mg/kg; and (5) diabetic rats treated with L-carnitine (300 mg/kg) + nitro-L-arginine (1mg/kg). Type 1 diabetes was induced by a single intraperitoneal injection of 110 mg/kg body weight alloxan. After 30 days, liver malondialdehyde levels, lipid profile, serum glucose, and glycated hemoglobin serum levels were measured. Results: Blood glucose, liver enzymes, glycated hemoglobin, and liver malondialdehyde levels significantly decreased in diabetic rats treated with L-carnitine compared to the untreated diabetic group (P<0.05). The co-administration of L-arginine and L-carnitine led to a significant decrease in glycated hemoglobin levels and serum glucose, in a manner similar to the group received only L-carnitine. Also, L-arginine and nitro-l-arginine had similar effects on liver lipid peroxidation and serum biochemical parameters. Conclusion: The results suggest that the hypoglycemic effect of L-carnitine is mediated independently from nitric oxide pathways. The interaction between L-carnitine and L-arginine may not be synergistic. So, their combined administration is not recommended for the diabetic patients

Construction of expression vectors carrying mouse peroxisomal protein gene (PeP) with GST and Flag labels

The aim of this study was to construct expression vectors carrying mouse peroxisomal protein gene (PEP-cDNA) in prokaryotic and mammalian expression vectors in chimeric cDNA types, encompassingGST and FLAG with PEP-cDNA. PEP-cDNA was sub-cloned in pGEX6p2 prokaryotic expression vector in order to label this gene with GST to purify PEP protein for further biochemical analysis and identifying related proteins thereafter. FLAG-PEP recombinant DNA was produced and sub-cloned inpUcD3 eukaryotic expression vector to express tagged-PEP protein for transient transfection analysis and identifying intracellular localization of PEP protein in future experiments. PEP-cDNA was amplifiedin different PCR reactions using pEGFP-PEP vector and 2 sets of primers introducing specific restriction sites at the ends of PEP. PCR products with BamHI/SalI restriction sites were treated by restriction enzymes and inserted into the pGEX6p2, downstream of GST tag. PEP-cDNA containingBamHI/ApaI restriction sites and FLAG gene (which amplified using pUcD3-FLAG-PEX3 vector) were used as templates in secondary PCR for amplifying FLAG-PEP recombinant DNA. FLAG-PEP fragment was treated by enzymatic digestion and inserted into the pUcD3 eukaryotic expression vector.pGEX6p2-PEP and pUcD3-FLAG-PEP constructed vectors were transformed into the one shot TOP10 and JM105 bacterial competent cells, respectively. Positive colonies were selected for plasmid preparation. Results confirmed correct amplification of the expected products. PEP-cDNA in both PCRreactions encompasses 630 bp. FLAG fragment containing designed sites was 77 bp and FLAG-PEP fragment was 700 bp. Sequencing of constructed vectors confirmed that PEP-cDNA was tagged appropriately and inserted free of mutation and in frame with GST and FLAG

COVID19 outbreak in Lombardy, Italy: An analysis on the short-term relationship between air pollution, climatic factors and the susceptibility to SARS-CoV-2 infection

Short-term exposure to air pollution, as well as to climate variables have been linked to a higher incidence of respiratory viral diseases. The study aims to assess the short-term influence of air pollution and climate on COVID19 incidence in Lombardy (Italy), during the early stage of the outbreak, before the implementation of the lockdown measures. The daily number of COVID19 cases in Lombardy from February 25th to March 10th, 2020, and the daily average concentrations up to 15 days before the study period of particulate matter (PM10, PM2.5), O3, SO2, and NO2 together with climate variables (temperature, relative humidity – RH%, wind speed, precipitation), were analyzed. A univariable mixed model with a logarithm transformation as link function was applied for each day, from 15 days (lag15) to one day (lag1) before the day of detected cases, to evaluate the effect of each variable. Additionally, change points (Break Points-BP) in the relationship between incident cases and air pollution or climatic factors were estimated. The results did not show a univocal relationship between air quality or climate factors and COVID19 incidence. PM10, PM2.5 and O3 concentrations in the last lags seem to be related to an increased COVID19 incidence, probably due to an increased susceptibility of the host. In addition, low temperature and low wind speed in some lags resulted associated with increased daily COVID19 incidence. The findings observed suggest that these factors, in particular conditions and lags, may increase individual susceptibility to the development of viral infections such as SARS-CoV-2

MiR-155 has a protective role in the development of non-alcoholic hepatosteatosis in mice

Hepatic steatosis is a global epidemic that is thought to contribute to the pathogenesis of type 2 diabetes. MicroRNAs (miRs) are regulators that can functionally integrate a range of metabolic and inflammatory pathways in liver. We aimed to investigate the functional role of miR-155 in hepatic steatosis. Male C57BL/6 wild-type (WT) and miR-155−/− mice were fed either normal chow or high fat diet (HFD) for 6 months then lipid levels, metabolic and inflammatory parameters were assessed in livers and serum of the mice. Mice lacking endogenous miR-155 that were fed HFD for 6 months developed increased hepatic steatosis compared to WT controls. This was associated with increased liver weight and serum VLDL/LDL cholesterol and alanine transaminase (ALT) levels, as well as increased hepatic expression of genes involved in glucose regulation (Pck1, Cebpa), fatty acid uptake (Cd36) and lipid metabolism (Fasn, Fabp4, Lpl, Abcd2, Pla2g7). Using miRNA target prediction algorithms and the microarray transcriptomic profile of miR-155−/− livers, we identified and validated that Nr1h3 (LXRα) as a direct miR-155 target gene that is potentially responsible for the liver phenotype of miR-155−/− mice. Together these data indicate that miR-155 plays a pivotal role regulating lipid metabolism in liver and that its deregulation may lead to hepatic steatosis in patients with diabetes

Investigation on feasibility polyculture of Litopenaeus vannamei with Mugil cephalus in earthen shrimp ponds

This study was conducted in order to optimizing of the biological condition and enhancing of the harvest efficiency for cultured shrimps of Guater site. Experimental design was consisted of three treatments and each treatment with three replications (totally 9 ponds with 600 m^2 area for each pond). After preparing and watering of ponds, the ponds was stocked with shrimp post larves in a density of 0.007±0.001 g (or 20 numbers per m^2) per m^2. After 35 days, the fingerlings of gray mullet were released to shrimp ponds in densities of 0/100 m^2 (T1/), 2/100 m^2 (T2) and 4/100 m^2 (T3). During experiment, the physicochemical parameters of water (temperature, O_2, pH, water transparency and salinity) were measured daily for two times (morning and afternoon). Also, the nitrate, nitrite, ammonia, phosphate and silicate concentrations and BOD5 as well as chlorophyll (a), phytoplanktons and zooplanktons were measured every 15 days one time. To determine the organic values of the bottom sediment of the ponds, monthly sampling was conducted. Health status of shrimps was investigated monthly too. Growth rate, mean weight, survival value, Food conversion ratios (FCR) and total shrimp harvest (Kg) were measured after 107 days rearing in ponds. ANOVA analysis showed significant differences between treatments. The highest (212 Kg, 3533 Kg; weight mean was18.4 g for each shrimp) and lowest (187 Kg, 3116 Kg; weight mean was16.23 g for each shrimp) of harvested shrimps were yielded in T3 and T1 respectively. There was not significant differences between treatments in terms of survival rate (P>0.05). After 107 days rearing, the highest (1.27 0.2) and lowest (1.2 0.1) of FCR were observed in T_3 and T_1 respectively. Although, there were no significant differences between T_2 and T_3 in ammonia, O_2, Total organic material, pH and BOD5, but, T_2 and T_3 had significant differences with T_1 in these parameters. In this study, 27 genus of phytoplanktons belonged to Diatoms (Bacillariophyceae), blue-green algal (Cyanophyceae) and dinoflagellates (Dinophyceae) were identified. Diatoms with 20 genus had more abundance than dinoflagellates (6 genus) and blue-green algal (1 genus). Also, 7 orders of zooplanktons including copepod, mollusks, nauplius of crustacean and rhizopoda were identified. Health investigation of T1 (without shrimp) showed more pathogenic pollution (parasites and bacteria) than in treatments with shrimp. In this regard, among bacteria, the Vibrio genus (V.Alginoliticus and V.Fluvialis) had more abundance and among parasites zoothamnium sp and Epistylis sp were identified which more abundance was for zoothamnium sp. In conclusion, our results concluded that mixed culturing of white shrimp and grey mullet in optimum densities is possible and is caused more production of shrimp

Targeting a cell-specific microRNA repressor of CXCR4 ameliorates atherosclerosis in mice

The CXC chemokine receptor 4 (CXCR4) in endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) is crucial for vascular integrity. The atheroprotective functions of CXCR4 in vascular cells may be counteracted by atherogenic functions in other nonvascular cell types. Thus, strategies for cell-specifically augmenting CXCR4 function in vascular cells are crucial if this receptor is to be useful as a therapeutic target in treating atherosclerosis and other vascular disorders. Here, we identified miR-206-3p as a vascular-specific CXCR4 repressor and exploited a target-site blocker (CXCR4-TSB) that disrupted the interaction of miR-206-3p with CXCR4 in vitro and in vivo. In vitro, CXCR4-TSB enhanced CXCR4 expression in human and murine ECs and VSMCs to modulate cell viability, proliferation, and migration. Systemic administration of CXCR4-TSB in Apoe-deficient mice enhanced Cxcr4 expression in ECs and VSMCs in the walls of blood vessels, reduced vascular permeability and monocyte adhesion to endothelium, and attenuated the development of diet-induced atherosclerosis. CXCR4-TSB also increased CXCR4 expression in B cells, corroborating its atheroprotective role in this cell type. Analyses of human atherosclerotic plaque specimens revealed a decrease in CXCR4 and an increase in miR-206-3p expression in advanced compared with early lesions, supporting a role for the miR-206-3p-CXCR4 interaction in human disease. Disrupting the miR-206-3p-CXCR4 interaction in a cell-specific manner with target-site blockers is a potential therapeutic approach that could be used to treat atherosclerosis and other vascular diseases

Endothelial overexpression of TGF-β-induced protein impairs venous thrombus resolution

Endothelial cells play a critical role during venous thrombus remodeling, and unresolved, fibrotic thrombi with irregular vessels obstruct the pulmonary artery in patients with chronic thromboembolic pulmonary hypertension (CTEPH). This study sought to identify endothelial mediators of impaired venous thrombus resolution and to determine their role in the pathogenesis of the vascular obstructions in patients with CTEPH. Endothelial cells outgrown from pulmonary endarterectomy specimens (PEA) were processed for mRNA profiling, and nCounter gene expression and immunohistochemistry analysis of PEA tissue microarrays and immunoassays of plasma were used to validate the expression in CTEPH. Lentiviral overexpression in human pulmonary artery endothelial cells (HPAECs) and exogenous administration of the recombinant protein into C57BL/6J mice after inferior Vena cava ligation were employed to assess their role for venous thrombus resolution. RT2 PCR profiler analysis demonstrated the significant overexpression of factors downstream of transforming growth factor beta (TGFβ), that is TGFβ-Induced Protein (TGFBI or BIGH3) and transgelin (TAGLN), or involved in TGFβ signaling, that is follistatin-like 3 (FSTL3) and stanniocalcin-2 (STC2). Gene expression and immunohistochemistry analysis of tissue microarrays localized potential disease candidates to vessel-rich regions. Lentiviral overexpression of TGFBI in HPAECs increased fibrotic remodeling of human blood clots in vitro, and exogenous administration of recombinant TGFBI in mice delayed venous thrombus resolution. Significantly elevated plasma TGFBI levels were observed in patients with CTEPH and decreased after PEA. Our findings suggest that overexpression of TGFBI in endothelial promotes venous thrombus non-resolution and fibrosis and is causally involved in the pathophysiology of CTEPH

Neutrophil microvesicles drive atherosclerosis by delivering miR-155 to atheroprone endothelium

Neutrophils are implicated in the pathogenesis of atherosclerosis but are seldom detected in atherosclerotic plaques. We investigated whether neutrophil-derived microvesicles may influence arterial pathophysiology. Here we report that levels of circulating neutrophil microvesicles are enhanced by exposure to a high fat diet, a known risk factor for atherosclerosis. Neutrophil microvesicles accumulate at disease-prone regions of arteries exposed to disturbed flow patterns, and promote vascular inflammation and atherosclerosis in a murine model. Using cultured endothelial cells exposed to disturbed flow, we demonstrate that neutrophil microvesicles promote inflammatory gene expression by delivering miR-155, enhancing NF-κB activation. Similarly, neutrophil microvesicles increase miR-155 and enhance NF-κB at disease-prone sites of disturbed flow in vivo. Enhancement of atherosclerotic plaque formation and increase in macrophage content by neutrophil microvesicles is dependent on miR-155. We conclude that neutrophils contribute to vascular inflammation and atherogenesis through delivery of microvesicles carrying miR-155 to disease-prone regions.British Heart Foundation Programme Grant (CS, PE); British Heart Foundation Project Grants PG/09/067/27901 (AB, VR), PG/13/55/30365 (LW, SF), PG/14/38/30862 (CR, VR), PG/16/44/32146 (JJ, EKT, SF); British Heart Foundation Studentship FS/14/8/30605 (BW, VR); MRC Fellowship MR/K023977/1 (RB); and European Union’s Horizon 2020 Marie Skłodowska-Curie Innovative Training Network, TRAIN 721532 (CN)