No abstract

Sleep deprivation (SD) has been associated with memory impairment through induction of oxidative stress. Melatonin, which promotes the metabolism of many reactive oxygen species (ROS), has antioxidant and neuroprotective properties. In this study, the effect of melatonin on memory impairment induced by 4 weeks of SD was investigated using rat animal model. Animals were sleep deprived using modified multiple platform model. Melatonin was administered via oral gavage (100 mg/kg/day). Spatial learning and memory were assessed using the radial arm water maze (RAWM). Changes in oxidative stress biomarkers in the hippocampus following treatments were measured using ELISA procedure. The result revealed that SD impaired both short- and long-term memory (P < 0.05). Use of melatonin prevented memory impairment induced by SD. Furthermore, melatonin normalized SD-induced reduction in the hippocampus activity of catalase, glutathione peroxidase (GPx), and superoxide dismutase (SOD). In addition, melatonin enhanced the ratio of reduced to oxidized glutathione GSH/GSSG in sleep-deprived rats (P < 0.05) without affecting thiobarbituric acid reactive substance (TBARS) levels (P > 0.05). In conclusion, SD induced memory impairment, which was prevented by melatonin. This was correlated with normalizing hippocampus antioxidant mechanisms during chronic SD.

No abstract

Lumbar disc degeneration (LDD) is a widespread public health problem that may lead to disability and loss of productivity. Adiponectin is an adipokine secreted by adipose tissue and has been shown to be involved in cartilage homeostasis. In the present study, the association between the rs266729 (−11377C/G) and rs2241766 (45T/G) single nucleotide polymorphisms (SNPs) in the adiponectin gene (ADIPOQ) and LDD was investigated. In addition, the correlation between the plasma adiponectin level and LDD was examined. A total of 289 subjects, 168 patients with LDD and 122 healthy individuals, were recruited in the study. All subjects were genotyped for rs266729 and rs2241766 SNPs using polymerase chain reaction-restriction fragment length polymorphism. Circulating levels of adiponectin protein were measured using the ELISA technique. A strong association was found between adiponectin level and LDD (P<0.01), where high levels of adiponectin were found in patients compared with healthy controls. The increase in adiponectin level was not affected by gender. However, no significant differences were found in the genotype distribution or allelic frequency of the two examined polymorphisms between patients with LDD and healthy controls (P>0.05). In conclusion, adiponectin appears to be elevated in patients with LDD. The rs266729 and rs2241766 SNPs in the ADIPOQ gene are not associated with LDD.

Tobacco smoking is a global health hazard that kills about 5 million people annually. Waterpipe smoking is among the most popular methods of tobacco consumption world-wide. In this study, we investigated whether waterpipe smoking impairs learning and memory in the hippocampus, a question of special concern due to the particular popularity of waterpipe use among youth. Additionally, possible molecular targets for expected learning and memory impairment were determined. In this study, rats were exposed to waterpipe smoke (WTS) by whole body exposure 1hr × 5 days/wk, for one month, and outcomes were compared to a control group exposed only to fresh air. Outcomes included spatial learning and memory using the Radial Arm Water Maze (RAWM), and oxidative stress biomarkers (catalase, GPx, SOD, GSH, GSSG, GSH/GSSG ratio). We found that WTS exposure led to impaired short- and long-term memory. This impairment was accompanied by reduced hippocampal activity of catalase, SOD, GPx, GSH, and GSH/GSSG, elevated GSSG, thus, marked changes in oxidative stress biomarkers. In conclusion, there is reason for concern that WTS exposure may impair cognitive ability.