Co-administration of Vitamins E and C protects against stress-induced hepatorenal oxidative damage and effectively improves lipid profile at both low and high altitude

The aim of this study was to evaluate the effect of co- administration of vitamins E and C on exhaustive exercise induced-stress in regards to hepatorenal function in rats native to low altitude (LA) and high altitude (HA). In both LA and HA areas, native wistar rats of each area were divided into three groups of 6 rats each, which include stress-free control, forced swimming-induced experimental stress and experimental stress plus vitamins E and C treatment. Lipid profile and Liver and kidney functions were assessed in both groups. HA and LA rats exhibit similar baseline levels of liver and kidney function as well as lipid metabolism profiles. However, HA rats showed decreased levels of antioxidant markers with an increased level of lipid peroxidation. Exhaustive swimming exercise induced a significant increase in the liver and kidney function of rats at both altitudes accompanied with a decrease in antioxidants levels. However, the magnitude of change observed in HA rats was more profound. Also at LA, forced swimming exercise resulted in a significant increase in serum total cholesterol (TChol), triacylglycerides (TAG) and high-density lipoprotein cholesterol (HDL). However, in HA rats, forced swimming exercise caused a significant decrease in serum TChol and low-density lipoprotein (LDL), except for HDL levels which were significantly elevated. Pre- and co-administration of vitamins E and C counteracted the induction of liver and/or kidney function by exhaustive exercise, and lowered TChol and LDL levels in rats at either altitude. In conclusion, at native high altitude: kidney and liver function essentially remained stable; response to stress included more profound oxidative damage to liver and kidney tissues as well as augmented deterioration in lipid metabolism compared to low altitude; and combined administration of vitamins E and C protected against observed oxidative stress damage to liver and kidney tissues and preserved lipid metabolism. At low altitude, combined administration of vitamin E and C protected against stress-induced oxidative damage to the liver and kidney and did preserve normal lipid metabolism, except for HDL. These novel findings reveal the pathophysiological changes in the liver function, kidney function and lipid metabolism occurring at high altitude specifically under stress, and demonstrate the efficacy of combined supplementation of vitamins E and C to normalize these changes.Key words: Exercise, oxidative stress, vitamin E, vitamin C, altitude, rats

Derangement of hemopoiesis and hematological indices in Khat (Catha edulis) - treated rats

The purpose of this study was to identify the sub-acute toxic effects of Khat (Catha edulis) on hemopoiesis and hematological indices of white albino rats. Two groups, each of 10 rats, were used. In the experimental group, a hydro-ethanol extract of C. edulis was administered orally to rats, daily, in single doses of 500 mg/kg body weight, for for weeks. The control group received equivalent amounts of normal saline. Our results show, for the first time, that oral administration of C. edulis hydro-ethanol extract caused significant derangement in hemopoiesis and in gross hematological indices in rats, characterized by macrocytic anemia and leucopenia. Our data show statistically significant decreases in total leukocytes count (TLC) in which, hemoglobin concentration (Hb. conc.), packed cell volume (PCV), and red cell count (RCC), accompanied by significant increases in mean cell volume (MCV), red blood cell distribution width (RDW) and platelets count with no change in mean hemoglobin concentration (MHC). In peripheral blood smears (PBS) of treated rats, there were evidences of dyserythropoiesis- impaired hemoglobinization, macrocytosis, poikilocytosis and anisocytosis, and dysgranulopoiesis- giant forms, hypersegmented neutrophils and bizarre nuclear shapes. In conclusion, our results indicate that oral administration of a hydro-ethanol extract of C. edulis adversely affected blood cell formation and induced macrocytic anemia and leukopenia in rats. However, the exact mechanisms of these hematological changes produced by Khat are still in need for further studies.Keywords:Catha edulis, hemopoiesis, anemia, leukopenia, ratsAfrican Journal of Biotechnology, Vol. 13(2), pp. 349-355, 8 January, 201

The relationship of body weight to altitude in preschool children of Southwestern Saudi Arabia

Objectives : To determine the average weight and height and the prevalence of overweight or obesity and thinness in preschool children of the Southwestern highlands of the Kingdom of Saudi Arabia and compare them with their counterparts living at lower altitudes. Methods : A cross-sectional study of 559 preschool children aged 12-71 months born and living permanently at high altitude, and 463 preschool children of comparable age born and living permanently at low altitude. For each child at high and low altitude, age was recorded and weight and height were measured. Weight for height Z-score with WHO standards was used for an assessment of normal weight, overweight or obesity and thinness. Results : The highland preschool children were found to be significantly heavier and taller than their counterparts living at low altitude. 92.1% of all highland preschool children and 67.6% of lowland preschool children were found to have normal weight (p < 0.0001). Overweight or obesity was insignificantly greater among preschool children of the highlands (2.3%) compared to the preschool children of the low lying areas (0.9%) (p<0.7). Thinness was significantly more prevalent among preschool children of the lowlands (31.5%) than preschool children of the highlands(5.5%) (p< 0.0001). At both high and low altitude, there were no significant differences in the prevalence of overweight or obesity and thinness between boys and girls. Conclusion : The findings of this study indicate that thinness is a major nutritional problem among lowland preschool children. This may be attributed to the prevailing tropical environmental conditions on the health of children at low altitude

The association between physical activity and overweight and obesity in a population of children at high and low altitudes in Southwestern Saudi Arabia

Objective: To assess the relationship between overweight and obesity and physical activity in Saudi children born and permanently domiciled at high and low altitudes in Southwestern Saudi Arabia. Subjects and Methods: A cross-sectional study of 145 healthy Saudi children aged 10–15 years who were born and lived permanently at high altitude (3000–3100 m) and 154 healthy Saudi children of comparable age who were born and lived permanently at a relatively low altitude (500 m) was conducted. For each subject selected, body weight and body height were measured using an Avery beam weighing scale and a stadiometer, respectively. Body mass index (BMI) was calculated using the equation BMI = (weight [kg]/height [m2]). Physical activity scores were determined using International Physical Activity Questionnaire-Short Form-A. Resting radial pulse rate (beat/minutes) was determined clinically. Results: Physical activity was significantly and inversely associated with overweight and obesity in boys at both high (χ2 = 15.8, P< 0.001) and low (χ2 = 14.7, P< 0.001) altitudes, but there was no clear trend for girls at either altitude. The lack of association between physical activity and overweight and obesity in girls was attributed to the low and homogeneous level of physical activity. Conclusion: Physical activity should be encouraged as a strategy for weight reduction in the overweight and the obese and the prevention of overweight and obesity in Saudi children at high and low altitudes

Lipopolysaccharide induces acute lung injury and alveolar haemorrhage in association with the cytokine storm, coagulopathy and AT1R/JAK/STAT augmentation in a rat model that mimics moderate and severe Covid-19 pathology.

Progress in the study of Covid-19 disease in rodents has been hampered by the lack of angiotensin-converting enzyme 2 (ACE2; virus entry route to the target cell) affinities for the virus spike proteins across species. Therefore, we sought to determine whether a modified protocol of lipopolysaccharide (LPS)-induced acute respiratory distress syndrome in rats can mimic both cell signalling pathways as well as severe disease phenotypes of Covid-19 disease. Rats were injected via intratracheal (IT) instillation with either 15 mg/kg of LPS (model group) or saline (control group) before being killed after 3 days. A severe acute respiratory syndrome (SARS)-like effect was observed in the model group as demonstrated by the development of a "cytokine storm" (>2.7 fold increase in blood levels of IL-6, IL-17A, GM-CSF, and TNF-α), high blood ferritin, demonstrable coagulopathy, including elevated D-dimer (approximately 10-fold increase), PAI-1, PT, and APTT (p 4 fold increase). Chest imaging revealed bilateral small patchy opacities of the lungs. Severe lung injury was noted by the presence of both, alveolar collapse and haemorrhage, desquamation of epithelial cells in the airway lumen, infiltration of inflammatory cells (CD45+ leukocytes), widespread thickening of the interalveolar septa, and ultrastructural alterations similar to Covid-19. Thus, these findings demonstrate that IT injection of 15 mg/kg LPS into rats, induced an AT1R/JAK/STAT-mediated cytokine storm with resultant pneumonia and coagulopathy that was commensurate with moderate and severe Covid-19 disease noted in humans

Cardiac Adaptive Responses After Hypoxia in an Experimental Model

The role of vascular endothelial growth factor (VEGF) and erythropoietin (EPO) in mediating hypoxic preconditioning under the acute intermittent hypoxic condition (AIH) was investigated in this study. Male Wistar rats were randomly assigned and kept in normoxic conditions, (Nx) or in AIH conditions and subjected to brief cycles hypoxia/reoxygenation. Hearts were isolated, perfused, and subjected to in vitro global ischemia followed by reperfusion. During and at the end of reperfusion, left ventricular developed pressure (LVDP); LV end diastolic pressure (LVEDP); rate pressure product (RPP); peak left ventricular pressure rise (Delta P/Delta t(max)) and heart rate (HR) were measured. Hearts subjected to AIH displayed a significant higher LVDP (P LT .001), RPP (P LT .001), and Delta P/Delta t(max) (P LT .001). Expression of VEGF and EPO were significantly increased at 3, 8, and 24 hours after AIH. Hypoxic training could provide a new approach to enhance endogenous cardioprotective mechanisms