scholarly journals Intermittent Hypoxia Exposure Can Prevent Reductions in Hemoglobin Concentration After Intense Exercise Training in Rats

2021 ◽  
Vol 12 ◽  
Author(s):  
Xiquan Weng ◽  
Hao Chen ◽  
Qun Yu ◽  
Guoqing Xu ◽  
Yan Meng ◽  
...  

Intense exercise training can induce low concentrations of hemoglobin, which may be followed by maladaptation. Therefore, it is important for athletes to prevent low concentrations of hemoglobin during intense exercise training. In this study, we explored whether different protocols of intermittent hypoxic exposure (IHE, normobaric hypoxia, 14.5% O2) could prevent the exercise training-induced reduction in hemoglobin concentration in rats. Six-week-old male Sprague-Dawley rats were subjected to progressive intense treadmill exercise training over three weeks followed by three weeks of training with IHE after exercise. IHE lasted either 1 h, 2 h, or 1 h + 1 h (separated by a 3-h interval) after the exercise sessions. Hematological parameters, including hemoglobin concentration [(Hb)], red blood cells (RBCs), and hematocrit (Hct), and both renal and serum erythropoietin (EPO) were examined. We found that intense exercise training significantly reduced [Hb], RBCs, Hct, food intake and body weight (P < 0.01). Analysis of reticulocyte hemoglobin content (CHr) and reticulocyte counts in the serum of the rats suggested that this reduction was not due to iron deficiency or other cofounding factors. The addition of IHE after the intense exercise training sessions significantly alleviated the reduction in [Hb], RBCs, and Hct (P < 0.05) without an obvious impact on either food intake or body weight (P > 0.05). Increase in reticulocyte count in the rats from the IHE groups (P < 0.05 or P < 0.01) suggests that IHE promotes erythropoiesis to increase the hemoglobin concentration. Furthermore, the addition of IHE after the intense exercise training sessions also significantly increased the concentration of renal EPO (P < 0.05), although the increase of the serum EPO level was statistically insignificant (P > 0.05). The different IHE protocols were similarly effective at increasing renal EPO and preventing the training-induced decreases in [Hb], RBCs, and Hct. Collectively, this study suggests that IHE may be used as a new strategy to prevent intense exercise training-induced reductions in [Hb], and deserves future exploration in athletes.

2021 ◽  
Vol 12 ◽  
Author(s):  
Xiquan Weng ◽  
Jieru Lin ◽  
Yu Yuan ◽  
Baoxuan Lin ◽  
Weiwei Huang ◽  
...  

In prolonged intense exercise training, the training load of athletes may be reduced once their hemoglobin concentrations ([Hb]s) are decreased dramatically. We previously reported that intermittent hypoxia exposure (IHE) could be used to alleviate the decrease of [Hb] and help to maintain the training load in rats. To further explore the feasibility of applying IHE intervention to athletes during prolonged intense exercise training, 6 trained swimmers were recruited to conduct a 4-week IHE intervention at the intervals after their [Hb] dropped for 10% or more during their training season. IHE intervention lasted 1 h and took place once a day and five times a week. Hematological and hormonal parameters, including [Hb], red blood cells (RBC), hematocrit (Hct), reticulocytes, serum erythropoietin (EPO), testosterone (T) and cortisol (C) were examined. After the IHE intervention was launched, [Hb], RBC and Hct of the subjects were increased progressively with their maximum levels (P < 0.01) showing at the third or fourth week, respectively. An increase in reticulocyte count (P < 0.01) suggests that IHE intervention promotes erythropoiesis to increase [Hb]. Besides, serum level of EPO, the hormone known to stimulate erythropoiesis, was overall higher than that before the IHE intervention, although it was statistically insignificant. Furthermore, the serum level of T, another hormone known to stimulate erythropoiesis, was increased progressively with the maximum level showing at the fourth week. Collectively, this study further confirms that IHE intervention may be used as a new strategy to prevent intense exercise training-induced reductions in [Hb].


2007 ◽  
Vol 293 (4) ◽  
pp. R1468-R1473 ◽  
Author(s):  
Michael F. Wiater ◽  
Bryan D. Hudson ◽  
Yvette Virgin ◽  
Sue Ritter

Leptin reduces body fat selectively, sparing body protein. Accordingly, during chronic leptin administration, food intake is suppressed, and body weight is reduced until body fat is depleted. Body weight then stabilizes at this fat-depleted nadir, while food intake returns to normal caloric levels, presumably in defense of energy and nutritional homeostasis. This model of leptin treatment offers the opportunity to examine controls of food intake that are independent of leptin's actions, and provides a window for examining the nature of feeding controls in a “fatless” animal. Here we evaluate macronutrient selection during this fat-depleted phase of leptin treatment. Adult, male Sprague-Dawley rats were maintained on standard pelleted rodent chow and given daily lateral ventricular injections of leptin or vehicle solution until body weight reached the nadir point and food intake returned to normal levels. Injections were then continued for 8 days, during which rats self-selected their daily diet from separate sources of carbohydrate, protein, and fat. Macronutrient choice differed profoundly in leptin and control rats. Leptin rats exhibited a dramatic increase in protein intake, whereas controls exhibited a strong carbohydrate preference. Fat intake did not differ between groups at any time during the 8-day test. Despite these dramatic differences in macronutrient selection, total daily caloric intake did not differ between groups except on day 2. Thus controls of food intake related to ongoing metabolic and nutritional requirements may supersede the negative feedback signals related to body fat stores.


Author(s):  
Javid Mansuri ◽  
Archana Paranjape

Objective: Evaluation of the anti-obesity effect of aqueous extract of Mucuna pruriens seeds on rats.Methods: Male Sprague-Dawley (SD) rats were subjected to high-fat diet (HFD) for 12 wk. L-DOPA (12.5 mg/kg, p. o.) as standard drug and aqueous extract of Mucuna pruriens (AEMP) seeds (200 mg/kg, p. o. and 400 mg/kg, p. o.) as test drugs were administered in last 4 wk along with HFD. Body weight, food intake, body mass index (BMI), serum total cholesterol (TC), triglyceride (TG) and high-density lipoprotein (HDL) levels were measured at the end of fourth, eighth and twelfth wk, while white adipose tissue (WAT) mass and brain dopamine levels were measured at the end of the twelfth wk.Results: AEMP (200 mg/kg, p. o.) and (400 mg/kg, p. o.) treated groups showed a significant decrease in food intake and weight gain without altering BMI. Moreover, TG levels were lower in treated groups as compared to the HFD group, but no significant changes were observed in TC and HDL levels. L-DOPA-treated group showed a significant decrease in body weight, food intake, BMI and WAT. Both AEMP and L-DOPA-treated groups showed an increase in brain dopamine levels as compared to disease control group (p<0.05).Conclusion: L-DOPA and AEMP showed anti-obesity activity by reducing body weight gains, food intake and WAT weights; modulating TG with increased brain dopamine level which correlates to the inhibitory action of dopamine on reward mechanism. 


2021 ◽  
Vol 10 ◽  
Author(s):  
Kazunari Kadokura ◽  
Tsuyoshi Tomita ◽  
Kohei Suruga

Abstract The fish paste product, fish balls ‘tsumire’, is a traditional type of Japanese food made from minced fish as well as imitation crab, kamaboko and hanpen. Although tsumire is known as a high-protein and low-fat food, there is a lack of scientific evidence on its health benefits. Hence, we aimed to investigate the effects of tsumire intake on organ weight and biomarker levels in Sprague–Dawley rats for 84 d as a preliminary study. Six-week-old male Sprague–Dawley rats were divided into two groups: group I, fed normal diets, and group II, fed normal diets with 5 % dried tsumire. Throughout the administration period, we monitored their body weight and food intake; at the end of this period, we measured their organ weight and analysed their blood biochemistry. No significant differences were observed with respect to body weight, food intake, organ weight and many biochemical parameters between the two groups. It was found that inorganic phosphorus and glucose levels were higher in group II rats than in group I rats. On the other hand, sodium, calcium, amylase and cholinesterase levels were significantly lower in group II than in group I. Interestingly, we found that the levels of aspartate aminotransferase, alanine transaminase, lactate dehydrogenase and leucine aminopeptidase in group II were significantly lower than in group I, and that other liver function parameters of group II tended to be lower than in group I. In conclusion, we consider that the Japanese traditional food, ‘tsumire,’ may be effective as a functional food for human health management worldwide.


2020 ◽  
Author(s):  
Clayton Spada ◽  
Chau Vu ◽  
Iona Raymond ◽  
Warren Tong ◽  
Chia-Lin Chuang ◽  
...  

Abstract Background Bimatoprost negatively regulates adipogenesis in vitro and likely participates in a negative feedback loop on anandamide-induced adipogenesis. Here, we investigate the broader metabolic effects of bimatoprost action in vivo in rats under both normal state and obesity-inducing conditions. Methods Male Sprague Dawley rats were a fed standard chow (SC) diet in conjunction with dermally applied bimatoprost treatment for a period of 9–10 weeks. Body weight gain, energy expenditure, food intake, and hormones associated with satiety were measured. Gastric emptying was also separately evaluated. In obesity-promoting diet studies, rats were fed a cafeteria diet (CAF) and gross weight, fat accumulation in SQ, visceral fat and liver was evaluated together with standard serum chemistry. Results Chronic bimatoprost administration attenuated weight gain in rats fed either standard or obesity-promoting diets over a 9–10 weeks. Bimatoprost increased satiety as measured by decreased food intake, gastric emptying and circulating gut hormone levels. Additionally, SQ and visceral fat mass was distinctly affected by treatment. Bimatoprost increased satiety as measured by decreased food intake, gastric emptying and circulating gut hormone levels. Conclusions These findings suggest that bimatoprost (and possibly prostamide F2α) regulates energy homeostasis through actions on dietary intake. These actions likely counteract the metabolic actions of anandamide through the endocannabinoid system potentially revealing a new pathway that could be exploited for therapeutic development.


2003 ◽  
Vol 21 (1) ◽  
pp. 51 ◽  
Author(s):  
E. M. Aregheore ◽  
K. Becker ◽  
H.P.S. Makkar

Seeds from a toxic variety of Jatropha curcas (Capo Verde, Nicaragua) were processed, defatted and ground to obtain the meal. The meal was subjected to heat and 14 different chemical treatments to detoxify the meal of lectin and phorbolesters. Heat treatment inactivated lectin, but not phorbolester. One of the treatments reduced phorbolesters to a tolerable level of 0.09 mg/g. The treated meals with other ingredients were used in diets to assess acceptance and nutritive value of detoxified Jatropha curcas meal in two experiments. Experiments 1 and 2 had twelve (12) male weanling rats each, Sprague Dawley strain, 28-30 days old, pre-experimental average body weights of 8379±7.2 and 84.6±6.4 g, respectively. They were divided into three groups according to body weight and fed casein diet (control) and two diets in which Jatropha curcas was the protein source. In experiment 1, the rats accepted diet 1, but did not fully accept diet 2. Food intake, growth rate, protein efficiency ratio (PER) and food transformation index (T1) were significantly better (P<0.05) in diet 1 than in the casein and diet 2. In experiment 2, casein diet was better (P<0.05) in food intake, growth rate, PER and TI than diets 1 and 2. Food intake with Jatropha meal was significantly reduced and the rats had drastic body weight loss (P<0.05) and this might be due to the presence of phorbolesters in the diets. Generally, the presence of phorbolesters in food has significant effect on its acceptance. Jatropha meal obtained from treatment 3 had a crude protein (CP) content of 68%, far higher than the CP content of most oilseed meals (soyabean). This treatment seems a better method of detoxifying Jatropha curcas meal for livestock but in economic terms it is expensive to produce a meal from it.


1957 ◽  
Vol 35 (1) ◽  
pp. 31-37 ◽  
Author(s):  
D. G. Montemurro ◽  
J. A. F. Stevenson

With the use of the Horsley–Clarke stereotaxic instrument, bilateral electrolytic lesions were placed in the lateral hypothalamic areas of female Sprague–Dawley rats. Changes in food and water intake and body weight were correlated with the histological localization of the lesions. Rats with large lesions in the frontal plane of the middle of the tuber cinereum died within a week of the operation. Food and water administered by stomach tube did not prevent weight loss and death.Two rats developed adipsia which lasted 13 and 16 days respectively; 10 ml. of tap water per day by stomach tube resulted in increases in food intake and body weight during the period of adipsia. These rats had lesions in the lateral hypothalamic areas in the frontal plane of the middle of the tuber cinereum, but these were small and relatively asymmetrical.Another rat refused water from the time of operation until sacrifice (55 days). Administration of 20 ml. per day of tap water caused an increase in food intake and body weight, and a general improvement. Whenever intake of water was not imposed by stomach tube, however, the food intake dropped and body weight was lost. This animal failed to drink spontaneously. The lesions in this animal were more symmetrical, slightly more dorsal, and about 0.75 mm. more posterior than those which produced temporary adipsia. In the rat, an area essential to the regulation of voluntary consumption of water appears to be located in the lateral hypothalamic areas at about the plane of the posterior ventromedial nuclei and the anterior border of the premammillary nuclei.


2009 ◽  
Vol 296 (5) ◽  
pp. H1312-H1320 ◽  
Author(s):  
Roshan P. Weerackody ◽  
David J. Welsh ◽  
Roger M. Wadsworth ◽  
Andrew J. Peacock

Hypoxia-induced endothelial dysfunction plays a crucial role in the pathogenesis of hypoxic pulmonary hypertension. p38 MAPK expression is increased in the pulmonary artery following hypoxic exposure. Recent evidence suggests that increased p38 MAPK activity is associated with endothelial dysfunction. However, the role of p38 MAPK activation in pulmonary artery endothelial dysfunction is not known. Sprague-Dawley rats were exposed to 2 wk hypobaric hypoxia, which resulted in the development of pulmonary hypertension and vascular remodeling. Endothelium-dependent relaxation of intrapulmonary vessels from hypoxic animals was impaired due to a reduced nitric oxide (NO) generation. This was despite increased endothelial NO synthase immunostaining and protein expression. Hypoxia exposure increased superoxide generation and p38 MAPK expression. The inhibition of p38 MAPK restored endothelium-dependent relaxation, increased bioavailable NO, and reduced superoxide production. In conclusion, the pharmacological inhibition of p38 MAPK was effective in increasing NO generation, reducing superoxide burden, and restoring hypoxia-induced endothelial dysfunction in rats with hypoxia-induced pulmonary hypertension. p38 MAPK may be a novel target for the treatment of pulmonary hypertension.


2006 ◽  
Vol 290 (3) ◽  
pp. E591-E597 ◽  
Author(s):  
Nadine Simler ◽  
Alexandra Grosfeld ◽  
André Peinnequin ◽  
Michèle Guerre-Millo ◽  
André-Xavier Bigard

Exposure to hypoxia induces anorexia in humans and rodents, but the role of leptin remains under discussion and that of orexigenic and anorexigenic hypothalamic neuropeptides remains unknown. The present study was designed to address this issue by using obese (Leprfa/Leprfa) Zucker rats, a rat model of genetic leptin receptor deficiency. Homozygous lean (LeprFA/LeprFA) and obese (Leprfa/Leprfa) rats were randomly assigned to two groups, either kept at ambient pressure or exposed to hypobaric hypoxia for 1, 2, or 4 days (barometric pressure, 505 hPa). Food intake and body weight were recorded throughout the experiment. The expression of leptin and vascular endothelial growth factor (VEGF) genes was studied in adipose tissue with real-time quantitative PCR and that of selected orexigenic and anorexigenic neuropeptides was measured in the hypothalamus. Lean and obese rats exhibited a similar hypophagia (38 and 67% of initial values at day 1, respectively, P < 0.01) and initial decrease in body weight during hypoxia exposure. Hypoxia led to increased plasma leptin levels only in obese rats. This resulted from increased leptin gene expression in adipose tissue in response to hypoxia, in association with enhanced VEGF gene expression. Increased hypothalamic neuropeptide Y levels in lean rats 2 days after hypoxia exposure contributed to accounting for the enhanced food consumption. No significant changes occurred in the expression of other hypothalamic neuropeptides involved in the control of food intake. This study demonstrates unequivocally that altitude-induced anorexia cannot be ascribed to anorectic signals triggered by enhanced leptin production or alterations of hypothalamic neuropeptides involved in anabolic or catabolic pathways.


2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
Sittichai Koontongkaew ◽  
Orapan Poachanukoon ◽  
Seewaboon Sireeratawong ◽  
Thaweephol Dechatiwongse Na Ayudhya ◽  
Parirat Khonsung ◽  
...  

Zingiber cassumunar Roxb. has been used for traditional medicine, but few studies have described its potential toxicity. In this study, the acute and chronic oral toxicity of Z. cassumunar extract granules were evaluated in Sprague-Dawley rats. The extract at a single dose of 5000 mg/kg body weight did not produce treatment related signs of toxicity or mortality in any of the animals tested during the 14-day observation period. However, a decrease in body weights was observed in treated males (P<0.05). The weights of lung and kidney of treated females were increased (P<0.05). Treated males were increased in spleen and epididymis weights (P<0.05). In repeated dose 270-day oral toxicity study, the administration of the extracts at concentrations of 0.3, 3, 30, 11.25, 112.5, and 1,125 mg/kg body weight/day revealed no-treatment toxicity. Although certain endpoints among those monitored (i.e., organ weight, hematological parameters, and clinical chemistry) exhibited statistically significant effects, none was adverse. Gross and histological observations revealed no toxicity. Our findings suggest that the Z. cassumunar extract granules are well tolerated for both single and chronic administration. The oral no-observed-adverse-effect level (NOAEL) for the extract was 1,125 mg/kg body weight/day for males and females.


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