The role of serotonergic and catecholaminergic systems for possible antidepressant activity of apigenin

Background and objectiveAlthough, the anti-depressant like effects of apigenin (APG) are documented in the literature, the underlying mechanism for exerting such an effect is still not clear. In this research, an attempt was made to determine the possible role of APG for antidepressant activity through serotonergic and catecholaminergic systems using standardized animal models.Materials and methodsThe antidepressant property of APG was determine by involving tail suspension (TST) and modified forced swimming tests (MFST). The effect of APG was evaluated at 25 and 50 mg/kg. In mechanistic models, animals were pretreated with catecholaminergic and serotonergic antagonists prior to administration of APG. The results obtained were statistically analyzed to determine the level of significance.ResultsThe period of immobility in both models (TST and MFST) was significantly reduced by APG (25 and 50 mg/kg). The best therapetuic dose of APG (50 mg/kg) was selected for the mechanistic study. The anti-immobility effect of APG declined to a significant extent upon pretreatment with catecholaminergic antagonists (α-methyl-para-tyrosine methyl ester; SCH 23390; sulpiride; phentolamine) and serotonergic inhibitors (p-clorophenylalanine-methyl-ester; ondansetron) in both TST and MFST models. The antidepressant benefits of apigenin were only modestly reversed when rats were given propranolol.ConclusionsThe findings suggest that APG's antidepressant effect is mediated by the α-adrenergic, dopaminergic and 5-HT3 serotonergic receptors.     

Health Hazard Assessment of Pyridaben Residues in Egyptian Strawberries

Dissipation behavior and hazard assessment of the insecticide/acaricide pyridaben applied to strawberries were investigated under the climatic conditions of Egypt. A validated gas chromatographic method (GC-μECD) was used to determine pyridaben residues when applied at the recommended rate and twice this rate. The average recoveries were in the range between 95.8% and 103% with associated relative standard deviation not exceeding 14.5%. The estimated limit of quantification for pyridaben was 0.005 mg/kg. The field results showed that pyridaben dissipated rapidly in strawberries and had a half-life of approximately 2.3 days. The hazard assessment was evaluated by using the hazard quotient (HQ). The results showed that the HQ value was significantly less than HQ = 1. This result implied that the hazard of pyridaben use in strawberries even at double the recommended dosage was negligible to human. This study could provide guidance for the safe and reasonable use of pyridaben in strawberries and to prevent health problems to consumers; however, further hazard assessment studies are needed to ascertain the hazard of pyridaben residues on strawberries to vulnerable groups, including children, pregnant women, and elderly consumers.     

Effects of elevated pCO2 on the photosynthetic performance of the sea ice diatoms Navicula directa and Navicula glaciei

Journal of Applied Phycology - Sea ice algal communities are generally dominated by pennate diatoms, which commonly occur at the ice-water interface and in brine channels. They also make a...     

Purification of Lectin from Micropropagated Roots Derived from Aseptic Seedling of <Emphasis Type="Italic">Canavalia ensiformis</Emphasis> L.

A well-organized protocol has been developed for high frequency root germination from the seed of Canavalia ensiformis on Murashige and Skoog (MS) medium. Surprisingly, the seeds that were grown on the MS medium having no growth hormone showed the best response. Roots of 30 days old aseptic seedling were homogenized and a lectin from them was purified on Sephadex G-50 affinity column. The finding that final product is a pure lectin was confirmed by specific hemagglutinating property. The final root lectin yield was 0.6% and eluted as a single peak. Root lectin specific activity was 50 times more than the seed lectin. Sugar specificity activity by hemagglutination-inhibition assay indicated that lectin belongs to glucose/mannose-specific group. Interestingly, the lectin was found to be 25 kDa, similar to molecular mass of Concanavalin A purified from seed of C. ensiformis, as revealed by SDS–PAGE. Thus, Concanavalin A from either source can be used for development of transgenic crops that are capable of expressing lectin gene and hence can efficiently perform biological nitrogen fixation by giving rise to nodules in their root. The advantage of this method is that purification of Concanavalin A in tissue culture conditions is easier, handy and is less time consuming.     

Comparative study of His- and Non-His-tagged CLIC proteins,reveals changes in their enzymatic activity

The chloride intracellular ion channel protein (CLIC) family are a unique set of ion channels that can exist as soluble and integral membrane proteins. New evidence has emerged that demonstrates CLICs' possess oxidoreductase enzymatic activity and may function as either membrane-spanning ion channels or as globular enzymes. To further characterize the enzymatic profile of members of the CLIC family and to expand our understanding of their functions, we expressed and purified recombinant CLIC1, CLIC3, and a non-functional CLIC1-Cys24A mutant using a Histidine tag, bacterial protein expression system. We demonstrate that the presence of the six-polyhistidine tag at the amino terminus of the proteins led to a decrease in their oxidoreductase enzymatic activity compared to their non-His-tagged counterparts, when assessed using 2-hydroxyethyl disulfide as a substrate. These results strongly suggest the six-polyhistidine tag alters CLIC's structure at the N-terminus, which also contains the enzyme active site. It also raises the need for caution in use of His-tagged proteins when assessing oxidoreductase protein enzymatic function.     

High level expression,purification and immunogenicity analysis of a protective recombinant protein against botulinum neurotoxin type E

Botulinum neurotoxin type E heavy chain consists of two domains: N-terminal half as a translocation domain and C-terminal half (Hcc) as a binding domain. In this research a synthetic gene fragment encoding the binding domain of botulinum neurotoxin type E (BoNT/E-Hcc) was highly expressed in Escherichia coli by pGEX4T-1 vector. After purification, the recombinant BoNT/E-Hcc was evaluated by SDS-PAGE and western blot (immunoblot) analysis. Average yields obtained in this research were 3.7 mg recombinant BoNT/E-Hcc per liter of bacterial culture. The recombinant protein was injected in mice for study of its protection ability against botulinum neurotoxin type E challenges. The challenge studies showed that, vaccinated mice were fully protected against 10⁴ × minimum lethal dose of botulinum neurotoxin type E.     

Effect of Zinc Supplementation on Physical and Psychological Symptoms,Biomarkers of Inflammation,Oxidative Stress,and Brain-Derived Neurotrophic Factor in Young Women with Premenstrual Syndrome: a Randomized,Double-Blind,Placebo-Controlled Trial

Biological Trace Element Research - To examine sex-specific associations of neonatal and childhood exposure to eight trace elements with cognitive abilities of school-age children. The association...     

Serum lipid profile in psoriatic patients: correlation between vascular adhesion protein 1 and lipoprotein (a)

Psoriasis is a chronic inflammatory skin disease characterized by excessive cellular replication. Apolipoproteins are genetically determined molecule whose role has been implied in cardiovascular pathology. Vascular adhesion protein?1 (VAP?1) is an adhesion molecule with an enzymatic activity that partakes in the migration process of lymphocytes into sites of inflammation. Our purpose was to evaluate the plasma lipid profiles, apolipoproteins (A1, B) and Lp (a) and VAP?1 in order to compare the lipid profile in psoriatic patients with non‐affected persons and correlation between VAP?1 and Lp (a). We determined serum concentrations of lipids, lipoproteins , apolipoproteins and VAP?1 in 90 patients with psoriasis and 90 age matched controls. Serum Lp (a), apo A1 and apo B were measured by immunoprecipitation assays, and the lipids and lipoproteins were measured by enzymatic methods.The VAP?1 were masured by ELISA method. The mean levels of total cholesterol, LDL, apo B and VAP?1 in patients with psoriasis were found to be significantly higher than those of healthy subjects (P<0.05. In psoriatic patients, elevation of VAP‐1 correlated with elevation of Lp (a) (p = 0.025). This study shows that high serum lipid level and VAP?1, is significantly more common in psoriasis. This fact may be responsible for higher prevalence of cardiovascular accident in psoriatic patients. Copyright © 2012 John Wiley & Sons, Ltd.