Assessment of titanium dioxide nanoparticles toxicity via oral exposure in mice: effect of dose and particle size.

Objective: The aim of the present work is to evaluate the toxicity of titanium dioxide nanoparticles (TiO2NPs) according to their doses and particle sizes. Materials and methods: The effect of five days oral administration of TiO2NPs (21 and 80 nm) with different doses (50, 250 and 500 mg/kg body weight) was assessed in mice via measurement of oxidative stress markers; glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) and nitric oxide (NO), liver function indices; aspartate and alanine aminotransferases (AST and ALT), chromosomal aberrations and liver histopathological pattern. Results: The results revealed drastic alterations in all the measured parameters and showed positive correlation with the gradual dose increment. In addition, the smaller particle size of TiO2NPS (21 nm) had more adverse effect in all the selected biochemical parameters, genetic aberrations and histological investigations. Conclusions: Toxicity of TiO2NPs increases in a dose-dependent manner and vice versa with particles size. The evaluated biomarkers are good indicators for TiO2NPs toxicity. More detailed studies are required before the recommendation of TiO2NPS as food additives.

Coenzyme Q10 and niacin mitigate streptozotocin- induced diabetic encephalopathy in a rat model.

Diabetic encephalopathy is an important complication of diabetes characterized by cognitive impairment, neurochemical and structural abnormalities. This study aimed to investigate the effect of coenzyme Q10 (CoQ10) and niacin as well as their combination in the treatment of encephalopathy associated with streptozotocin (STZ)- induced diabetes in rats. Glibenclamide (reference diabetic drug) and donepezil hydrochloride (acetylcholinesterase inhibitor) were also evaluated. Diabetes was induced by a single intraperitoneal injection of STZ (60 mg/kg). One month after STZ injection, diabetic rats were treated with the aforementioned drugs for two weeks. The evaluation was done through measuring glucose level, total antioxidant capacity (TAC), interleukin 6 (IL6), DNA degradation as well as serotonin and noradrenaline as neurotransmitters. The present data illustrated that combining CoQ10 and niacin exhibiting the most potent effect in improving the measured parameters and ameliorating some of diabetes complications.

A Therapeutic Insight of Niacin and Coenzyme Q10 Against Diabetic Encephalopathy in Rats.

Diabetes mellitus (DM) is characterized by hyperglycemia due to insulin inactivity or insufficiency with increasing risk of developing specific complications, including retinopathy, nephropathy, neuropathy, and atherosclerosis. The aim of the present study is to evaluate the efficacy of coenzyme Q10 (CoQ10), niacin, as well as their combination in ameliorating brain disorders associated with streptozotocin (STZ)-induced diabetes in rats. Glibenclamide, a reference diabetic drug, and donepezil, an acetylcholine inhibitor drug, were also evaluated. Diabetes was induced by single intraperitoneal injection of STZ (60 mg/kg body weight (b.wt)). One-month diabetic rats were treated with the selected drugs daily for another two consecutive weeks. The evaluation was done through the estimation of the levels of blood glucose, serum insulin, and oxidative stress markers: malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH); neurotransmitters: acetylcholinesterase (AchE) and dopamine (DA); vasoconstrictor indices: intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1(VCAM-1), and angiotensin II (Ang II); and apoptosis markers: tumor necrosis factor-α (TNF-α) and caspase-3 as well as the histopathological picture of the cerebellum region of the brain. The results revealed that the combination of niacin and CoQ10 improved most of the measured parameters with variable degrees. In conclusion, niacin and CoQ10 are promising dietary supplements in the management of diabetic encephalopathy.