The simultaneous action of acute paradoxical sleep deprivation and hypothyroidism modulates synaptosomal ATPases and acetylcholinesterase activities in rat brain.

BACKGROUND: Thyroid dysfunctions as well as sleep abnormalities are usually followed by neurological, psychiatric and/or behavioral disorders. On the other hand, changes in the brain adenosine triphosphatases (ATPases) and acetylcholinesterase (AChE) activities show significant importance in pathogenetic pathways in the evolution of numerous neuropsychiatric diseases. METHODS: This study aimed to evaluate the in vivo simultaneous effects of hypothyroidism and paradoxical sleep deprivation for 72 h on synaptosomalATPases and AChE activities of whole rat brains. In order to induce hypothyroidism, 6-n-propyl-2-thiouracil was administrated in drinking water during 21 days. The modified multiple platform method was used to induce paradoxical sleep deprivation. The AChE and ATPases activities were measured using spectrophotometric methods. RESULTS: Hypothyroidism significantly increased the activity of Na+/K+-ATPase compared to other groups, while at the same time significantly decreased AChE activity compared to the CT and SD groups. Paradoxical sleep deprivation significantly increased AChE activity compared to other groups. The simultaneous effect of hypothyroidism and sleep deprivation reduced the activity of all three enzymes (for Na+/K+-ATPase between HT/SD and HT group p < 0.0001, SD group p < 0.001,CT group p = 0.013; for ecto-ATPases between HT/SD and HT group p = 0.0034, SD group p = 0.0001, CT group p = 0.0007; for AChE between HT/SD and HT group p < 0.05, SD group p < 0.0001, CT group p < 0.0001). CONCLUSIONS: The effect of simultaneous existence of hypothyroidism and paradoxical sleep deprivation reduces the activity of the Na+/K+-ATPase, ecto-ATPases, and AChE, what is different from individual effect of hypothyroidism and paradoxical sleep deprivation itself. This knowledge could help in the choice of appropriate therapy in such condition.

Cadmium significantly changes major morphometrical points and cardiovascular functional parameters during early development of zebrafish.

Living organisms are commonly exposed to cadmium and other toxic metals. A vast body of research has shown the significant effects of these toxic metals on developmental processes. In order to study the role of toxic metals on early developmental stages of eukaryotes, we explored the effect of cadmium (Cd2+) contaminant on zebrafish. Thus, zebrafish embryos were exposed to 3 mg/L (16.7 µM) Cd2+ for 96 h and imaged every 24 h from the exposure onwards. Hatching rates of the eggs were determined at 72 h, followed by analyses at 96 h for: survival rate, morphometrical factors, and functional parameters of the cardiovascular system. Interestingly enough, significant hatching delays along with smaller cephalic region and some morphological abnormalities were observed in the treatment group. Moreover, substantial changes were noticed in the length of notochord and embryo, absorption of yolk sac with shorter extension, area of swimming bladder, as well as pericardium sac after Cd2+ treatment. Cadmium also caused significant abnormalities in heart physiology which could be the leading cause of mentioned morphological deformities. Herein, our results shine light on systematic acute embryological effects of cadmium in the early development of zebrafish for the first time.

The effects of cold-induced stress on liver oxidative injury during binge drinking.

The aim of our study was to evaluate the effects of cold stress on hepatic oxidative damage during binge drinking in rats. Male Wistar rats were divided into the following groups: group 1: control; group 2: ethanol-treated; group 3: stress-exposed; group 4: stress-exposed and ethanol-treated group. Oxidative and nitrosative stress parameters in the liver were determined spectrophotometrically, 12 h after treatment. Liver malondialdehyde concentration was significantly higher in group 4 when compared with groups 2 and 3. The highest increase in nitric oxide concentration was demonstrated in group 4 in comparison with groups 2 and 3. Superoxide dismutase (SOD) activity was significantly lower in group 4 when compared with groups 2 and 3. Ethanol administration induced a larger decrease in the activity of copper-/zinc-SOD in group 4 in comparison with group 2. Activity of manganese-SOD (Mn-SOD) was significantly higher in groups 3 and 4, when compared with control values, but the greatest increase in the activity of Mn-SOD was demonstrated in group 2. We also evaluated statistically significant decrease in the level of reduced gluthatione in the liver of group 4 in comparison with group 3. Based on our study, it can be concluded that cold-exposed stress and binge ethanol drinking have additive effects in imbalance between pro-oxidant and antioxidant defense system in liver.