Some blood genetic markers of selected tribes in Western Saudi Arabia

A total of 292 randomly selected subjects belonging to two indigenous Arab tribes (Harbi and Ghamid) and two immigrant tribes (Mograbi and Mowallad), residents in Western Saudi Arabia, have been tested for genetic variants of six blood groups, four serum proteins, and five red cell enzyme systems. The distribution of the polymorphic systems was different between indigenous and immigrant tribes, and the present Arab population shows a considerable degree of admixture from the surrounding countries, in particular Africa.     

Protective effect of resveratrol on acute endotoxemia-induced nephrotoxicity in rat through nitric oxide independent mechanism

Lipopolysaccharide (LPS) is a glycolipid component of the cell wall of gram negative bacteria inducing deleterious effects on the kidney. Endotoxemia-induced nephrotoxicity is characterized by disturbed intracellular redox balance and reactive oxygen species (ROS) accumulation leading to DNA, proteins and membrane lipid damages. Resveratrol (trans-3,5,4′-trihydroxystilbene) is a polyphenol displaying antioxidant and anti-inflammatory properties. This study investigated its effects on LPS-induced nephrotoxicity in rats. Resveratrol counteracted all LPS-induced changes in renal haemodynamic parameters. In the kidney resveratrol abrogated LPS-induced lipoperoxidation and antioxidant enzyme activities depletion as superoxide dismutase (SOD) and catalase (CAT) but not peroxidase (POD) activity. LPS increased plasma and urine nitric oxide (NO) level and resveratrol reversed them. More importantly, LPS-induced iron mobilization from plasma to kidney, which was also abolished by resveratrol treatment. All these results suggest that resveratrol exerted strong antioxidant properties against LPS-induced nephrotoxicity and that its mode of action seemed to involve iron shuttling proteins.     

Neuropharmacological screening of two 1,5-benzodiazepine compounds in mice

This work investigates whether the two 1,5-benzodiazepine compounds: 4-(2-hydroxyphenyl)-1,5-benzodiazepin-2-one (RG0501) and Benzopyrano [4,3-c] 1,5-benzodiazepine (RG0502) have any neuropharmacological activities. Diazepam and Flunitrazepam were used as drug references. The investigational 1,5-BDZ were tested in vivo for potentiating hexobarbital-induced sleep and pentylenetetrazole (PTZ)-induced seizures. Our study demonstrated that the increase of sleep duration was significantly higher with RG0501 as compared to RG0502. However, RG0502 anticonvulsant effect was more pronounced than that of RG0501 in the range dose of 6.25-37.5 mg.kg^-1. From the 50 mg.kg^-1 dose, RG0502 offered a protection against clonic-tonic seizures as well as lethality (p ≤ 0.05). The results showed that the required doses to obtain a pharmacological activity were more than those of the references. This difference could be related to the lack of specific substituants responsible for the pharmacological activity in the tested compounds.     

Improved functional vasodilation in obese Zucker rats following exercise training

Obese individuals exhibit impaired functional vasodilation and exercise performance. We have demonstrated in obese Zucker rats (OZ), a model of morbid obesity, that insulin resistance impairs functional vasodilation via an increased thromboxane receptor (TP)-mediated vasoconstriction. Chronic treadmill exercise training improves functional vasodilation in the spinotrapezius muscle of the OZ, but the mechanisms responsible for the improvement in functional vasodilation are not clear. Based on evidence that exercise training improves insulin resistance, we hypothesized that, in the OZ, exercise training increases functional vasodilation and exercise capability due to decreases TP-mediated vasoconstriction associated with improved insulin sensitivity. Six-week-old lean Zucker rats (LZ) and OZ were exercised on a treadmill (24 m/min, 30 min/day, 5 days/wk) for 6 wk. An oral glucose tolerance test was performed at the end of the training period. We measured functional vasodilation in both exercise trained (spinotrapezius) and nonexercise trained (cremaster) muscles to determine whether the improved functional vasodilation following exercise training in OZ is due to a systemic improved insulin resistance. Compared with LZ, the sedentary OZ exhibited impairments in glucose tolerance and functional vasodilation in both muscles. The TP antagonist SQ-29548 improved the vasodilator responses in the sedentary OZ with no effect in the LZ. Exercising training of the LZ increased the functional vasodilation in spinotrapezius muscle, with no effect in the cremaster muscle. Exercising training of the OZ improved glucose tolerance, along with increased functional vasodilation, in both the spinotrapezius and cremaster muscles. SQ-29548 treatment had no effect on the vasodilator responses in either cremaster or spinotrapezius muscles of the exercise-trained OZ. These results suggest that, in the OZ, there is a global effect of exercising training to improve insulin resistance and increase functional vasodilation via a decreased TP-mediated vasoconstriction.     

Isolation and characterisation of an isoproturon-mineralising Methylopila sp. TES from French agricultural soil

Using enrichment culture three isoproturon (IPU) mineralising bacterial isolates were isolated from a French agricultural soil mineralising up to 50% of the initially added 14C-ring labelled IPU within only eight days. These isolates showed similar metabolic (BIOLOG GN) and amplified rDNA restriction (ARDRA) profiles. Partial 16S rDNA sequencing revealed that they were identical and identified as Methylopila sp TES. This strain harbours a large plasmid (220 kb) putatively bearing essential IPU-degrading genes as demonstrated by a curing experiment. Methylopila sp. TES transformed IPU and its known metabolites to CO2 and biomass but did not degrade chlorotoluron, monolinuron, diuron and linuron.     

Protective effect of resveratrol against LPS-induced extracellular lipoperoxidation in AR42J cells partly via a Myd88-dependent signaling pathway

Lipopolysaccharides (LPS) are major components of the cell wall of Gram negative bacteria implicated in the pathogenesis of bacterial infection. Resveratrol is a polyphenolic phytoalexin exhibiting antioxidant and anti-inflammatory properties. We investigated the protective effects of this natural compound on LPS-induced proinflammatory effect using non-myeloid AR42J pancreatic cells. We found that LPS dose-dependently increased extracellular malondialdehyde (MDA) and nitric oxide without affecting their intracellular level whereas resveratrol abolished all these deleterious effects. LPS increased CD14 expression; IRAK1 and a phosphorylated form of p38 MAPK protein. Resveratrol counteracted LPS effect by decreasing CD14 and IRAK1 expression but unexpectedly increased the p38 MAPK protein phosphorylation. Altogether, our data highlighted the functionality of the TLR4-Myd88 signaling pathway in LPS pro-oxidant effect using non-myeloid cells. They further suggested that resveratrol exerted antioxidant properties either by a Myd88-dependent way not involving IRAK1 or by a TRIF dependent pathway.     

The Full-Length Mu-Opioid Receptor: A Conformational Study by Circular Dichroism in Trifluoroethanol and Membrane-Mimetic Environments

The secondary structure content of the recombinant human mu-opioid receptor (HuMOR) solubilized in trifluoroethanol (TFE) and in detergent micelles was investigated by circular dichroism. In both conditions, this G protein-coupled receptor adopts a characteristic alpha-helical structure, with minima at 208 and 222 nm as observed in the circular dichroism spectra. After deconvolution of spectra, the alpha-helix contents were estimated to be in the range of 50% in TFE and in sodium dodecyl sulfate at pH 6. These values are in accordance with the predicted secondary structure content determined for the mu-opioid receptor. A pH-dependent effect was observed on the secondary structure of the receptor solubilized in detergents, which demonstrates the essential role of ionic and hydrophobic interactions on the secondary structure. Circular dichroism spectra of EGFP-HuMOR, a fusion protein between the enhanced green fluorescent protein (EGFP) and the mu-opioid receptor, and EGFP solubilized in TFE were also analyzed as part of this study.     

Strain selection of microalgae isolated from Tunisian coast: characterization of the lipid profile for potential biodiesel production

Bioprocess and Biosystems Engineering - Microalgae could be of importance for future biodiesel production as an alternative for a third generation of biofuels. To select the most appropriate strain...     

Comparative Studies of Phytochemical Screening,HPLC‐PDA‐ESI‐MS/MS‐LC/HR‐ESI‐MS Analysis,Antioxidant Capacity and in Vitro Fermentation of Officinal Sage (Salvia officinalis L.) Cultivated in Different Biotopes of Northwestern Tunisia

We aimed in the present study to investigate the chemical composition, the antioxidant capacities as well as the in vitro fermentation properties of Salvia officinalis leaves aqueous extract (SOLAE) grown in four regions of northwestern Tunisia. Our data firstly indicated a spatial variation (P<0.05) in condensed tannins, total lipids, polyphenols and flavonoids contents. The HPLC‐PDA‐ESI‐MS/MS‐LC/HR‐ESI‐MS technique allowed to the identification of 13 phenolic compounds and showed that protocatechuic acid is the major constituent of the plant leaves grown in Tabarka, Ain Draham and Testour. The SOLAE of the plant grown in Tabarka presents the most potent scavenging activity against DPPH radical and had the highest percentage of inhibition. More importantly, we found in the present study that the digestibility of dry matter and in vitro fermentation showed a significant variation between the regions and the animal species. Also, we showed a very positive correlation between antioxidant properties and phenolic compounds contents. In conclusion, we suggest that SOLAE had potential beneficial effects owing in part to its antioxidant and ROS scavenging activities. Therefore, S. officinalis can be proposed as an additive food for animals’ nutrition and health.