Toxicity of titanium dioxide nanoparticles: Effect of dose and time on biochemical disturbance, oxidative stress and genotoxicity in mice.

The toxic impact of titanium dioxide nanoparticles (TiO2NPs) on human health is of prime importance owing to their wide uses in many commercial industries. In the present study, the effect of different doses and exposure time durations of TiO2NPs (21nm) inducing oxidative stress, biochemical disturbance, histological alteration and cytogenetic aberration in mice liver and bone marrow was investigated. Different doses of (TiO2NPs) (50, 250 and 500mg/kg body weight) were each daily intrapertioneally injected to mice for 7, 14 and 45days. Aspartate and alanine aminotransferases (AST &ALT), gamma glutamyl transpeptidase (GGT), total protein, total antioxidant capacity (TAC), malondialdehyde (MDA), glutathione (GSH), catalase (CAT) and nitric oxide (NO) levels were measured. The work was extended to evaluate the liver histopathological pattern and the chromosomal aberration in mice spinal cord bone marrow. The results revealed severe TiO2NPs toxicity in a dose and time dependent manner with positive correlation (r=0.98) for most investigated biochemical parameters. The same observation was noticed for the histological analysis. In case of cytogenetic study, chromosomal aberrations were demonstrated after injection of TiO2NPs with 500mg/kg b. wt. for 45days. In conclusion, the selected biochemical parameters and the liver architectures were influenced with dose and time of TiO2NPs toxicity, while the genetic disturbance started at the high dose of exposure and for long duration. Further studies are needed to fulfil the effect of TiO2NPs on pharmaceutical and nutritional applications.

Phytochemical composition, protective and therapeutic effect on gastric ulcer and α-amylase inhibitory activity of Achillea biebersteinii Afan.

Three sesquiterpene lactones [two germacranolides (micranthin and sintenin) and one guaianolide (4ß,10α-dihydroxy-5ß,7ß,8ßH-guaia-1,11(13)dien-12,8α-olide)] and four derivatives of 3-methoxy flavones (santin, quercetagetin-3,6,3'-trimethyl ether, quercetagetin-3,6-dimethyl ether, and 5,7 dihydroxy 3,3',4'-trimethoxy flavone) were isolated from the ethyl acetate extract (EAE) of the aerial parts of Achillea biebersteinii Afan. (Asteraceae). Evaluation of protective and therapeutic effects of EAE against ethanol-induced gastric ulcer in rats was carried. Antiulcer activity evaluation was done through measuring ulcer indices, stomach acidity, gastric volume and lesion counts. Oxidative stress markers; malondialdehyde, glutathione and superoxide dismutase were also estimated. The work was extended to determine the histopathological assessment of the stomach. Gastric ulcer exhibited a significant elevation of the ulcer index and oxidative stress markers. The extract attenuated these increments and recorded protective and therapeutic effects against gastric ulcer. Hyperglycaemia increases the mucosal susceptibility to ulcerogenic stimuli and predisposes gastric ulceration. In vitro α-amylase inhibitory assay was applied to evaluate the post prandial antihyperglycaemia activity. The result showing that the EAE has the ability to reduce starch-induced postprandial glycaemic excursions by virtue of potent intestinal α-amylase inhibitory activity. These findings demonstrated the remarkable potential of A. biebersteinii as valuable source of antiulcer agent with post prandial hyperglycaemia lowering effect.

Therapeutic potential of ginger against renal injury induced by carbon tetrachloride in rats.

The objective of this study was to evaluate the potential of successive ginger extracts (petroleum ether, chloroform, and ethanol) against nephrotoxicity induced by CCl(4) in rats. The evaluation was done through measuring kidney antioxidant parameters: glutathione (GSH), lipid peroxides (LPO), and superoxide dismutase (SOD). Renal function test: urea, creatinine and serum protein values, were also evaluated. The work was extended to examine tissue inflammatory mediators, prostaglandin-E(2) (PGE(2)), collagen content and the kidney histopathology. Severe alterations in all biomarkers were observed after injury with CCl(4). Treatment with ginger extracts resulted in markedly decreased levels of LPO, PGE(2), collagen and kidney function tests, while increased levels of GSH, SOD and serum protein were observed. In conclusion, extracts of ginger, particularly the ethanol, resulted in an attractive candidate for the treatment of nephropathy induced by CCl(4) through scavenging free radicals, improved kidney functions, inhibition of inflammatory mediators, and normalizing the kidney histopathological architecture. Further studies are required in order to identify the molecules responsible of the pharmacological activity.

Biomphalaria alexandrina snails as immunogens against Schistosoma mansoni infection in mice.

Despite effective chemotherapy, schistosomiasis remains the second largest public health problem in the developing world. Currently, vaccination is the new strategy for schistosomiasis control. The presence of common antigenic fractions between Schistosoma mansoni and its intermediate host provides a source for the preparation of a proper vaccine. The objective of this paper is to evaluate the nucleoprotein extracted from either susceptible or resistant snails to protect against schistosomiasis. The vaccination schedule consisted of a subcutaneous injection of 50 µg protein of each antigen followed by another inoculation 15 days later. Analyses of marker enzymes for different cell organelles [succinate dehydrogenase, lactate dehydrogenase (LDH), glucose-6-phosphatase, acid phosphatase and 5'-nucleotidase] were carried out. Energetic parameters (ATP, ADP, AMP, phosphate potentials, inorganic phosphate, amino acids and LDH isoenzymes) were also investigated. The work was extended to record worm and ova counts, oogram determination in the liver and intestine and the histopathological pattern of the liver. The nucleoprotein of susceptible snails showed reduction in worm and ova counts by 70.96% and 51.31%, respectively, whereas the nucleoprotein of resistant snails showed reductions of 9.67% and 16.77%, respectively. In conclusion, we found that the nucleoprotein of susceptible snails was more effective in protecting against schistosomiasis.

Biomphalaria alexandrina snails as immunogens against Schistosoma mansoni infection in mice

Despite effective chemotherapy, schistosomiasis remains the second largest public health problem in the developing world. Currently, vaccination is the new strategy for schistosomiasis control. The presence of common antigenic fractions between Schistosoma mansoni and its intermediate host provides a source for the preparation of a proper vaccine. The objective of this paper is to evaluate the nucleoprotein extracted from either susceptible or resistant snails to protect against schistosomiasis. The vaccination schedule consisted of a subcutaneous injection of 50 µg protein of each antigen followed by another inoculation 15 days later. Analyses of marker enzymes for different cell organelles [succinate dehydrogenase, lactate dehydrogenase (LDH), glucose-6-phosphatase, acid phosphatase and 5'-nucleotidase] were carried out. Energetic parameters (ATP, ADP, AMP, phosphate potentials, inorganic phosphate, amino acids and LDH isoenzymes) were also investigated. The work was extended to record worm and ova counts, oogram determination in the liver and intestine and the histopathological pattern of the liver. The nucleoprotein of susceptible snails showed reduction in worm and ova counts by 70.96 percent and 51.31 percent, respectively, whereas the nucleoprotein of resistant snails showed reductions of 9.67 percent and 16.77 percent, respectively. In conclusion, we found that the nucleoprotein of susceptible snails was more effective in protecting against schistosomiasis.