The metabolic syndrome (MetS) has become a global public health burden due to its link to cardiovascular disease and diabetes mellitus. The present study was designed to characterize the metabolic and cardiovascular disturbances, as well as changes in gut microbiota associated with high-fructose high-fat diet (HFFD)-induced MetS in Watanabe heritable hyperlipidemic (WHHL) rabbits. Twenty-one Watanabe rabbits were assigned to a control (n = 9) and HFFD (n = 12) groups, receiving a chow diet and a HFFD, respectively. During a 12-weeks protocol, morphological parameters were monitored; plasma fasting levels of lipids, glucose and insulin were measured and a glucose tolerance test (GTT) was performed. HOMA-IR was calculated. Cardiac function and vascular reactivity were evaluated using the Langendorff isolated heart and isolated carotid arteries methods, respectively. 16S rRNA sequencing of stool samples was used to determine gut microbial composition and abundance. HFFD-fed Watanabe rabbits exhibited increased fasting insulin (p < 0.03, 12^th week vs. Baseline), HOMA-IR (p < 0.03 vs. Control), area under the curve of the GTT (p < 0.02 vs. Control), triglycerides (p < 0.05, 12^th week vs. Baseline), TC (p < 0.01 vs. Control), LDL-C (p < 0.001 vs. Control). The HFFD group also displayed a significant decrease in intestinal microbial richness, evenness and diversity (FDR < 0.001, FDR < 0.0001, FDR < 0.01, respectively vs. Control group) and an increase in its Firmicutes/Bacteroidetes ratio (R = 3.39 in control vs. R = 28.24 in the HFFD group) indicating a shift in intestinal microbial composition and diversity. Our results suggest that HFFD induces insulin resistance and gut microbiota dysbiosis and accentuates dyslipidemia; and that, when subjected to HFFD, Watanabe rabbits might become a potential diet-induced MetS animal models with two main features, dyslipidemia and insulin resistance.

Viperidae snakes venoms represent a source of efficient bioactive components that have already led to the development of several new drugs. In this work, we analyzed the protein content of the Montivipera bornmuelleri crude venom using LC-ESI-MS, sephadex G-75 gel filtration and SDS-PAGE and demonstrated the presence of proteins with molecular masses corresponding to metalloprotease III, serine-protease and PLA2 in three fractions collected after gel filtration. Equally, we examined the antimicrobial effect of the venom that showed an important potency, as bactericidal agent, based on MBC and MIC values obtained, against Staphylococcus aureus and Morganella morganii bacteria. However, no activity was registered against Enterococcus faecalis, being the most resistant bacteria, neither against Aspergillus flavus and Penicillium digitatum fungal. Furthermore, on eleven other bacterial strains and the Candida albicans fungus, the venom has shown an intermediate efficacy by slightly reducing the growth. Our data concerning the Montivipera bornmuelleri venom give evidence of a rich and complex content aiding the exploration of new bioactive molecules for biopharmaceuticals purposes.

Phospholipase A2 (PLA2), a common toxic component of snake venom, is responsible for a wide spectrum of biological and toxicological effects including bactericidal, anticoagulant, hemolytic, as well as neurotoxic and cardiotoxicity activities. In the present work, phospholipase A2 named (Mb-PLA2) was isolated from the venom of Montivipera bornmuelleri a Lebanese snake, by a two-step procedure consisting of gel filtration chromatography on Biogel P60 and reverse phase high pressure liquid chromatography (RP-HPLC) on a Restek Ultra II C₁₈ column. The experimentally determined molecular weight of the Mb-PLA2 was 13650 Da, which was determined by electrospray ionization mass spectrometry and close to 14400 Da as judged by SDS-PAGE electrophoresis. The isolated Mb-PLA2 was evaluated for bactericidal activity against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. Mb-PLA2 showed strong antibacterial activity against the Gram positive bacteria S. aureus, followed by the Gram negative bacteria, E. coli, and then P. aeruginosa. Moreover, the Mb-PLA2 exhibited hemolytic activity toward human erythrocyte, as well as an anticoagulant activity when evaluated on human plasma.

Objectives: In experimental pharmacology, drug effect studies currently establish and analyse cumulative concentration–response curves (CCRC) under repeated measurements designs. Usually the CCRC parameters are estimated using the Hill's function in a nonlinear regression for independent data. The two-way analysis of variance is generally used to identify a statistical difference between the responses for two treatments but that analysis does not take into account the nonlinearity of the model and the heteroscedasticity (uneven distribution) of the data. We presently tested the possibility of finding a statistical solution for the nonlinear response in repeated measurements data using the nonlinear mixed effects (nlme) models. Methods: Experimental data sets, originating from studies on β-adrenoceptor-induced relaxation in rat thoracic aorta ring, were analysed using the nlme methods. Key findings: Comparison with classical methods showed the superiority of the nlme models approach. For each pharmacological parameter (Em, n, pD2), a point estimate, a standard error and a confidence interval are returned by the nlme procedures respecting the assumption of independency and normality of the residuals. Conclusions: Using the method presently described, it is now possible to detect significant differences for each pharmacological parameter estimated in different situations, even for designs with small samples size (i.e. at least six complete curves).