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Publications (18)26.18 Total impact

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    ABSTRACT: Aging is associated with decline in cardiovascular, autonomic function, and brain-derived neurotropic factor (BDNF). Reports are scanty regarding whether yoga can improve age-related degenerative changes in healthy active men. This study is designed to appraise the role of yoga in improving age-related degenerative changes in cardiometabolic risk profile, autonomic function, stress, and BDNF. Healthy active males of three age groups (20-29, 30-39, and 40-49 years) were randomly assigned to practice yoga daily 1 h for 3 months. Significantly higher values of heart rate (HR), blood pressure (BP), load in heart (DoP), myocardial oxygen consumption (RPP), and total cholesterol (TC) were noted in senior age group. HR, BP, DoP, RPP, and TC decreased significantly following yogic practice. High frequency (HF), total power (TP), all time domain variables of heart rate variability (HRV), and skin conductance (SC) were significantly decreased with advancement of age. HF, TP, and time domain parameters of HRV and SC increased significantly following yogic practice. Higher levels of catecholamines and low frequency (LF) power of HRV was noted with advancement of age. Levels of catecholamines and LF significantly decreased following yogic practice. Cortisol and adrenocorticotropic hormone (ACTH) level raised in senior age group. BDNF, serotonin, and dopamine were low in higher age group. Significant decrement of cortisol; ACTH; and increment in serotonin, dopamine, and BDNF was noted following yogic practice. This study revealed that yogic practices might help in the prevention of age-related degeneration by changing cardiometabolic risk factors, autonomic function, and BDNF in healthy male.
    Age 08/2014; 36(4):9683. · 6.28 Impact Factor
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    ABSTRACT: To evaluate the effects of yogic practice on resting metabolism and redox status. Study was conducted on 64 physically trained male volunteers selected randomly at Airforce Academy, Dundigal. The yoga group (n = 34) practiced yogasana, pranayama and meditation for 3 months (February - May 2011) and control group (n = 30) performed physical training. Antioxidant variables in blood samples along with physiological parameters were estimated before and after 3 months. No significant difference was noted between baseline data of control group and yoga group. Reduced glutathione, vitamin C, vitamin E, the ratio of reduced to oxidized glutathione and total antioxidant status were increased significantly following yogic practice. Activities of superoxide dismutase, glutathione S - transferase and glutathione reductase were significantly increased, whereas activity of glutathione peroxidase significantly decreased following yogic practice. Oxidized glutathione decreased significantly following yogic practice. A nonsignificant decrease of hydroperoxides, protein carbonyl, malondialdehyde and blood sugar was noted in the yoga group. Carbon dioxide elimination and peripheral oxygen saturation increased significantly following yogic practice. No significant changes were observed in the control group following 3 months of physical training. Regular yogic practice can improve resting metabolism and redox status of the practitioner.
    Journal of Physical Activity and Health 05/2014; · 1.95 Impact Factor
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    ABSTRACT: Objective: The aim of the study was to evaluate the effect of yogic practice on age related changes in antioxidants and redox status, resting metabolism and energy expenditure. Methods: The study was conducted on 60 healthy male volunteers of three age groups viz 20-29 years, 30-39 years and 40-50 years. In addition to their routine activities, volunteers practiced yogasana, pranayama and meditation for a period of 3 months. Blood samples were collected in fasting condition before and after 3 months of yogic practice for the estimation of biochemical parameters. Results: Oxygen consumption and energy expenditure were decreased with the advancement of age and after yogic practice. Respiratory quotient was increased with the age and decreased after yogic practice. Advancement of age showed progressive shifting of redox status towards the oxidized state, which restored by yogic practice. Lowered levels of reduced glutathione, the ratio of reduced to oxidized glutathione, total antioxidant status, vitamin C and vitamin E as well as the activity of enzymes such as superoxide dismutase, catalase, glutathione reductase and glutathione S-transferase were associated with aging. The regular yogic practice helps to improve in these above mentioned parameters. Hydroperoxides, protein carbonyl, malondialdehyde and glutathione peroxidase levels were found to be higher due to progression of age. These have been decreased after yogic practice. Conclusion: Regular yogic practices have the ability to revert back with the changes in antioxidant and redox status due to advancement of age.
    Journal of Experimental and Integrative Medicine. 08/2013; 3(4):305-312.
  • Rameswar Pal, Som Nath Singh, Mantu Saha
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    ABSTRACT: Objective : It is now well established that oxidative stress is a major risk factor for the development of several metabolic and degenerative disorders as well as implemented in aging process. The modern lifestyle is known to produce various physical and psychological stresses and make the individuals prone to oxidative stress as well. The aim of this study was to evaluate the effect of yogic practices on peripheral oxygen saturation and the oxidative stress. Method : The study was conducted on healthy male volunteers of two groups viz. yoga (n = 34) and control group (n = 08). In addition to their routine activities, the yoga group practiced yogasana, pranayama and meditation for 3months and control group did not practice the same. Blood samples were collected in fasting condition before and after 3 months of yogic practice. Reduced and oxidized glutathione, malondialdehyde, total antioxidant status, glutathione peroxidase, catalase and peripheral arterial oxygen saturation were estimated. Results : Reduced glutathione and total antioxidant status increased significantly (P<0.001) where as glutathione peroxidase activity (P < 0.001), plasma concentration level of malondialdehyde (P<0.01) and oxidized glutathione (P<0.01) decrease significantly in yoga group after completion of 3 months of yogic practice. Peripheral arterial oxygen saturation also increased in yoga group. Nosignificant change in any variable was noted in control group. Conclusion : Regular yogic practice helps in improving antioxidant and redox status of yoga practitioners.
    Indian journal of physiology and pharmacology 12/2011; 55(5 (Suppl)):53 - 54.
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    ABSTRACT: Nutritional requirements of sailors and submariners are different from those of ground forces as they work under confined environment as well as due to logistic constraints of cooking and storage of food. Study was conducted for a period of three months at Eastern Naval Command to evaluate nutrient requirements, nutritional status of Indian Navy personnel and adequacy of the existing ration scales. The study volunteers were from crew of two warships (n = 35) and submariners (n = 20) who were attached to their mother ships during time of data collection and offshore during rest of the period. Energy expenditure, nutrient intake, level of nutrients in body, and urinary excretion were measured along with changes in body composition. All variables were analysed before and after three months of nutritional monitoring. Energy expenditure at ship was in the range of 2449-4907 kcal/day with a mean of 3313 � 578 kcal/day, while in the case of submariners, it was 3168 � 282 (2606-3907) kcal/day. The energy intake in the case of sailors and submariners was not different either on shore establishment or at ship. Energy intake was found to be 3518 � 286 kcal/day. The energy contribution from carbohydrates, fats, and protein was 59.9 per cent, 27.8 per cent and 12.3 per cent, respectively. No sign and symptoms of any nutritional deficiency were observed either initially or after three months. Status of micronutrients present in their blood and in their urinary excretions along with body composition were maintained, indicating adequacy of existing ration scales of Indian Navy.
    Defence science journal 11/2011; 61(6):540-544. · 0.36 Impact Factor
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    ABSTRACT: Present study was aimed to investigate antioxidant and hepatoprotective activities of phenolic rich fraction (PRF) of Seabuckthorn leaves on CCl(4) induced oxidative stress in Sprague Dawley rats. Total phenolic content was found to be 319.33 mg gallic acid equivalent (GAE)/g PRF and some of its phenolic constituents, such as gallic acid, myricetin, quercetin, kaempferol and isorhamnetin were found to be in the range of 1.935-196.89 mg/g of PRF as determined by reverse-phase high-performance liquid chromatography (RP-HPLC). Oral administration of PRF at dose of 25-75 mg/kg body weight significantly protected from CCl(4) induced elevation in aspartate aminotransferase (AST), alanine aminotransferase (ALT), γ-glutamyl transpeptidase (GGT) and bilirubin in serum, elevation in hepatic lipid peroxidation, hydroperoxides, protein carbonyls, depletion of hepatic reduced glutathione (GSH) and decrease in the activities of hepatic antioxidant enzymes; superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR) and glutathione-S-transferase (GST). The PRF also protected against histopathological changes produced by CCl(4) such as hepatocytic necrosis, fatty changes, vacuolation, etc. The data obtained in the present study suggests that PRF has potent antioxidant activity, prevent oxidative damage to major biomolecules and afford significant protection against CCl(4) induced oxidative damage in the liver.
    Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 06/2011; 49(9):2422-8. · 2.99 Impact Factor
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    ABSTRACT: Reactive oxygen and nitrogen species have been reported to be increased due to hypobaric hypoxia. It was hypothesized that lowlanders are more susceptible to protein nitration, lipid peroxidation and DNA damage at high altitude than highlanders and formation of these biomarkers may have strong correlation with oxygen consumption. Male volunteers were randomly selected and categorized into 3 groups, i.e. lowlanders at sea level (LL-SL, n=10), lowlanders at an altitude of 4560 m (LL-HA, n=10) and highlanders (HAN, n=10). Volunteers performed maximal aerobic exercise. Resting and post-exercise blood samples were taken at sea level and high altitude. Both resting and maximum oxygen consumption showed positive correlation with stress markers. LL-HA showed increased 3-nitrotyrosine and lipid hydroperoxide than LL-SL at rest. 3-Nitrotyrosine and lipid hydroperoxide increased after exercise in 3 groups, but percentage increase was higher in HAN than LL-SL and LL-HA. LL-SL and HAN showed significant DNA damage after exercise. Results indicate that resting oxygen consumption is positively correlated with nitrosative and oxidative stress markers irrespective of environmental condition and adaptation levels. Lowlanders have shown higher susceptibility to hypoxic insult than highlanders at rest, but when subjected to exercise test, they showed better tolerance to hypoxia than highlanders.
    Respiratory Physiology & Neurobiology 03/2010; 171(2):115-21. · 2.05 Impact Factor
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    ABSTRACT: Acclimatization to high altitude (HA) is accompanied by decrease in plasma atrial natriuretic peptide (ANP). On the other hand, circulating levels of the hormone are known to be influenced by age and ethnicity. The impact of these factors on ANP response during prolonged HA exposure remains unexplored. Hence, this study was conducted to examine possible age and ethnic variation in plasma proANP(1-98) levels in men after 3 to 4 weeks at HA. Lowlanders (LL) were studied at sea level (SL) and after 3 to 4 weeks at an altitude of approximately 4500 m. The LL group comprised Rajput (n = 48), Gorkha (n = 40), and South Indian (n = 43) ethnicities. Another group of HA natives (Ladakhi, n = 40) were studied at approximately 4500 m only. Subjects were between 20 and 50 years of age. Estimation of plasma proANP(1-98) and biochemical, hematologic, and physiologic evaluation was done. In LL at HA, proANP(1-98) levels decreased (P < .001); plasma arginine vasopressin decreased (P < .05 in Rajputs and South Indians); and total protein, hemoglobin, and hematocrit increased (P < .05). Heart rate increased (P < .05), whereas arterial oxygen saturation decreased (P < .05) in all LL at HA. Ethnicity but not age variation in proANP(1-98) was observed under HA stress. In HA natives, plasma proANP(1-98) was higher than LL at HA and did not exhibit any age variation. Plasma proANP(1-98) levels, reflecting medium-term ANP secretion, decrease during prolonged exposure to HA in LL. This is due to diuresis leading to plasma volume reduction that occurs during the acclimatization process. Ethnicity but not age variation is associated with plasma proANP(1-98) under HA stress.
    Wilderness and Environmental Medicine 03/2010; 21(1):11-6. · 1.49 Impact Factor
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    ABSTRACT: High altitude (HA) is a multi-stressor environment comprising hypobaric hypoxia and cold. Climatic temperature varies with seasonal variation at HA. The present study was undertaken to investigate the effect of ambient temperature on antioxidant profile among sojourners at HA. The study was conducted on sojourners exposed to an altitude of 4,560 m in two different seasons and categorized into two groups (SOJ 1, n=63, ambient temp. at HA: -6 degree to +10degreeC; SOJ 2, n=81, ambient temp. at HA: 3degree-22degreeC). Blood was collected at sea level (SL) and after 4 weeks of HA exposure. Antioxidant enzymes showed significant upregulation in SOJ 2 at HA. In SOJ 1, superoxide dismutase and glutathione peroxidase showed significant upregulation but catalase and glutathione reductase showed significant decrease at HA. Non-enzymatic antioxidants showed significant reduction in SOJ 1 whereas a sustained antioxidant profile was observed in SOJ 2 at HA. Oxidative stress markers showed higher levels in SOJ 1 than SOJ 2 at HA. Differences observed between SOJ 1 and SOJ 2 at HA may be the consequence of different environmental temperatures. Cold stress was higher in SOJ 1 as evidenced from the significantly lower oral temperature in SOJ 1 as compared to SOJ 2. Cold- and hypoxia-induced increase in energy expenditure was significantly high in SOJ 1 than SOJ 2. To conclude, chronic exposure to hypoxia in moderate climatic temperature has a potential preconditioning effect on antioxidant system, but exposure to both cold and hypoxia causes greater oxidative stress due to altered metabolic rate.
    International Journal of Biometeorology 01/2010; 54(1):85-92. · 2.59 Impact Factor
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    ABSTRACT: Comparative studies on the adaptation pattern of antioxidant status among high altitude natives and acclimatized sojourners are very scanty. The aim of the present study was to compare the differences in antioxidant profile between two groups of active male volunteers, i.e. native highlanders (HAN, n=66) in their natural hypoxic environment with that of sojourners (SOJ, n=81) from sea level (SL) after 4 weeks of stay at an altitude of 4560m. Blood samples of SOJ were collected at SL and HA. Same was collected from HAN once at HA. HAN had significantly higher SOD activity and significantly lower catalase, GPX and GR activities than SOJ at HA. Ratio of GSH/GSSG was also significantly higher in HAN than SOJ at HA. In SOJ, antioxidant profile showed an upregulation after HA stay but it was not effective to reduce the levels of oxidative stress markers. Therefore, it can be stated that lifelong exposure to hypoxia has beneficial adaptive effects on antioxidant system in HAN. Similarly, acclimatization to HA also has beneficial preconditioning effects on antioxidant system in SOJ, but, may not be sufficient to ameliorate oxidative stress completely. Transient increase in metabolic rate due to hypoxia may be a causative factor for excess free radical generation among sojourners at HA.
    Respiratory Physiology & Neurobiology 06/2009; 167(3):255-60. · 2.05 Impact Factor
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    ABSTRACT: Hormonal changes during high-altitude (HA) exposure are important for normal adaptation to the new environment in lowlanders. Prolactin (PRL), a stress hormone, is involved in the regulation of fertility, immune response, osmotic balance, and angiogenesis. However, little is known about the effect of age and ethnicity on plasma PRL changes in men during prolonged HA exposure. The aim of this research was to examine possible age and ethnic variation in plasma PRL levels in men after 3 to 4 weeks of stay at HA (approximately 4500 m) in the Indian population. Lowlanders of Rajput (n = 49), Gorkha (n = 70), and South Indian (n = 40) ethnicities were studied at sea level (SL). They were taken to an altitude of approximately 4500 m where they stayed for 3 to 4 weeks. Another group of HA natives (Ladakhi, n = 65) was studied at similar altitude. Subjects were between 20 to 50 yr of age. At HA, plasma PRL showed a decrease in Rajputs and Gorkhas (p < 0.05), whereas there was an increase (p < 0.05) in South Indians when compared to SL. There was no age variation in PRL. PRL levels in HA natives were within the SL normal range observed in lowlanders. PRL response to HA stress in lowlanders is influenced by ethnicity. The exact cause for such differences in PRL secretion under HA stress is not clearly known. Further studies on the physiological regulation of PRL at HA are needed.
    High altitude medicine & biology 01/2009; 10(4):343-8. · 1.58 Impact Factor
  • Sanchari Sinha, Som Nath Singh, Uday Sankar Ray
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    ABSTRACT: Hypobaric hypoxia causes oxidative stress and the antioxidant system of the body plays a vital role in controlling it. Urate contributes up to two-thirds of the antioxidant capacity of human blood. The urate production is catalyzed by xanthine oxidase with a concomitant release of free radicals. This study was designed to appraise the role of urate as an antioxidant at high altitude. The study was conducted on 92 male lowlanders and 66 highlanders after ascent to high altitude at 4560 m. Blood was collected at sea level and after 4 weeks of high altitude exposure. In lowlanders, a significant increase in levels of hydroperoxide (551.4 +/- 4.2 micromol/mL vs. 582.0 +/- 3.55, p < 0.001], protein carbonyl (2.4 +/- 0.11 micromol/mL/mg protein vs. 3.03 +/- 0.11, p < 0.001), TAS (1.02 +/- 0.01 mmol/L vs. 1.19 +/- 0.02, p < 0.001), and UA (298.0 +/- 6.68 micromol/L vs. 383.0 +/- 6.55, p < 0.001) was observed at high altitude. These measurements were significantly lower in highlanders than in lowlanders at high altitude. Total antioxidant status (TAS) and uric acid (UA) showed a positive correlation in lowlanders at sea level and in highlanders at high altitude. Hydroperoxide and TAS also showed a positive correlation in both groups at high altitude. This indicates increased oxidative stress at high altitude despite an increase in antioxidant capacity in lowlanders. To conclude, a hypoxia-induced increase in UA contributes an appreciable portion of plasma total antioxidant capacity, but may not be effective in preventing oxidative stress at high altitude.
    High altitude medicine & biology 01/2009; 10(3):269-74. · 1.58 Impact Factor
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    Vasudha Shukla, Manish Vashistha, Som Nath Singh
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    ABSTRACT: Aqueous and alcoholic extracts of amalki (Emblica officinalis), spirulina and wheatgrass were prepared and analyzed for antioxidant vitamin content (vitamin C and E), total phenolic compounds. Antioxidant status, reducing power and effect on glutathione S-transferase (GST) activity were evaluated in vitro. Vitamin C content of crude amalaki powder was found to be 5.38 mg/g, while very less amount 0.22 mg/g was detected in wheat grass. Amalki was rich in vitamin E like activity, total phenolic content, reducing power and antioxidant activity. Total antioxidant activity of aqueous extract of amalki, spirulina and wheat grass at 1mg/ml concentration were 7.78, 1.33 and 0.278 mmol/l respectively. At similar concentrations the total antioxidant activity of alcoholic extract of amalaki, spirulina and wheat grass was 6.67, 1.73 and 0.380 mmol/l respectively. Amalki was also found to be rich source of phenolic compounds (241mg/g gallic acid equivalent). Alcoholic extract of wheat grass showed 50 % inhibition in FeCl(2)- ascorbic acid induced lipid peroxidation of rat liver homogenates in vitro. Both aqueous and alcoholic extracts of amalaki inhibited activity of rat liver glutathione S-transferase (GST) in vitro in dose dependant manner. Since GST acts as powerful drug metabolizing enzyme its inhibition by amalaki offers possibility of its use for lowering therapeutic dose of herbal preparations. The aqueous extracts of both amalki and spirulina also showed protection against t-BOOH induced cytotoxicity and production of ROS in cultured C(6) glial cells.
    Indian Journal of Clinical Biochemistry 01/2009; 24(1):70-5.
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    ABSTRACT: Several studies suggest that yoga can decrease oxidative stress. However reports are scanty regarding whether yoga training can improve the glutathione level of individual. This study is designed to appraise the role of yoga in maintaining glutathione (reduced and oxidized) levels and antioxidant status. This study was conducted on healthy male volunteers from the Indian Navy, who were divided into two groups--a yoga (n = 30) group and a control (n = 21) group. The yoga group was trained in yoga for 6 months. The yoga schedule consisted of prayers, asana, pranayama, and meditation. The control group practiced routine physical training exercise for 6 months. Blood samples were collected when the volunteers were in fasting condition before and after completion of 6-month training period. Reduced and oxidized glutathione, glutathione reductase activity and total antioxidant status (TAS) were estimated. Reduced glutathione level increased significantly (p < 0.05) in the yoga group after completion of training. Glutathione reductase activity increased significantly in the control group (p < 0.05). TAS increased significantly (p < 0.001) in the yoga group and decreased significantly (p < 0.001) in the control group. Regular practice of yoga can maintain or improve antioxidant level of the body. The clinical relevance is that yoga practice can be used to maintain the antioxidant defense system under stressful conditions of training as observed in the case of soldiers and athletes.
    The Journal of Alternative and Complementary Medicine 12/2007; 13(10):1085-90. · 1.46 Impact Factor
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    ABSTRACT: To evaluate the effect of L-carnitine supplementation on improving endurance exercise in normobaric/normoxic and hypobaric/hypoxic environments. Six-week-endurance-trained male Sprague-Dawley rats (n = 24) were randomly divided into 2 groups: control and experimental; the latter group was supplemented with L-carnitine, administered orally in a dose of 100 mg x kg(-1) body weight. The animals were supplemented for 25 days under ambient normobaric/normoxic conditions and thereafter were exposed to 72 hours of hypobaric hypoxia equivalent to 6100 m. The supplementation was continued during the exposure. "Run to exhaustion" was recorded on day 1 (R1) (presupplementation) and on days 7 (R2), 14 (R3), 21 (R4), and 28 (R5, which followed the last 72 hours of hypoxic exposure) of supplementation. Food intake, body weight, and the biochemical measures of plasma glucose, total cholesterol, and high-density lipoprotein (HDL) cholesterol were recorded. There was a significant improvement in endurance exercise, as indicated by an increase in run to exhaustion following L-carnitine supplementation under normobaric normoxia (36%-39%) and hypobaric hypoxia (50%). L-carnitine supplementation had no effect on plasma glucose levels either at sea level or after hypoxic exposure. Total cholesterol was decreased in normoxic and HDL cholesterol was increased in normoxic and hypoxic conditions, indicating a beneficial effect of exercise. L-carnitine supplementation improved exercise endurance in rats exposed to normobaric normoxic and hypobaric hypoxic conditions. Such supplementation would be beneficial in delaying the onset of fatigue during prolonged exercise in both conditions, indicating its potentially beneficial use at high altitude.
    Wilderness and Environmental Medicine 02/2007; 18(3):169-76. · 1.49 Impact Factor
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    ABSTRACT: High altitude (HA) exposure usually leads to a significant weight loss in non-acclimatized humans. Anorexia is believed to be the main cause of this body weight loss. Appetite regulatory peptides, i.e. leptin and neuropeptide Y play a key role in food intake and energy homeostasis. Recent studies suggests increased oxidative stress during HA exposure. In present study effect of HA exposure on levels of leptin and NPY was evaluated along with N-acetyl cysteine (NAC) and vitamin E supplementation in relation to food intake and body weight changes. The study was conducted on 30 healthy male volunteers (age 19-29 years). Subjects were divided randomly into three groups of 10 each. Group 1 (placebo) supplemented with 400 mg of calcium gluconate, group 2 and 3 were supplemented with 400 mg of NAC and 400 mg vitamin E, respectively per day. The study was conducted at low altitude (320 m, Phase I), at HA 3600 m (Phase II) and at an altitude of 4580 m (Phase III). On HA exposure significant reduction in plasma leptin levels was observed in all the groups on day 2 (Phase II) along with decrease in food intake and reduction in body weight. Statistically significant increase in blood malondialdehyde (MDA) levels was seen in all the groups on HA exposure (Phase II, Day 2), but the maximum increase was in case of placebo group (65.1%) on day 2 (Phase II) in comparison to low altitude values. The decrease in energy intake was almost same in all the groups indicating that antioxidant supplementation did not provide any protection against HA anorexia. From the study, it may be concluded that leptin and oxidative stress possibly are not the key players for HA anorexia.
    Nutritional Neuroscience 01/2007; 10(5-6):243-9. · 1.65 Impact Factor
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    ABSTRACT: Antarctica presents an inhospitable environment due to extreme low temperature, high wind velocity, low humidity, snowstorms, long polar days and nights, high level of UV radiations, magnetic storms and increased ionisation along with social isolation and sexual deprivation. Acclimatisation to any new condition is associated with certain metabolic changes along with alteration in nutritional requirements. There are reports of increased food intake and gain in body weight during past Indian Antarctic expeditions. Therefore, the present study was undertaken with the aim to assess the changes in appetite regulatory peptides i.e. leptin and neuropeptide Y in relation to energy intake and expenditure of the Antarctic expeditioners. The study was conducted in three phases viz. Phase I at Goa (basal), Phase II 48 h after reaching Antarctica and Phase III after one month of stay at Antarctica. Energy and nutrient intake were analysed from the duplicate plate samples of the expeditioners. Energy expenditure was computed using 24 h activity records for 7 days. Blood samples were collected in each phase for biochemical estimations. After reaching Antarctica, the expeditioners were active and the total energy expenditure (mean +/- SEM, n = 10) was found to be 3120 +/- 474 kcal/day. The actual energy intake was found to be 3911 +/- 310 kcal/day. This indicates that the Antarctic expeditioners had very active life and weight gain during expedition could be due to positive energy balance. After 48 h of stay at Antarctica plasma leptin levels (mean +/- SEM, n = 22) decreased from normal basal values 5.66 (+/- 0.59) ng/ml (Phase I) to 4.40 (+/- 0.37) ng/ml (Phase II), even though there was an increase in body fat. Increased level of plasma leptin was observed in Phase III as compared to phase I and II. Concomitantly there was increase in plasma neuropeptide Y levels from 0.303 (+/- 0.004) ng/ml to 1.211 (+/- 0. 27) ng/ml (p < 0.001) in Phase II and decrease in Phase III. The decrease in plasma leptin levels and increase in neuropeptide Y levels in Phase II may be responsible for increase in appetite and gain in body weight at Antarctica.
    Nutritional Neuroscience 08/2005; 8(4):233-8. · 1.65 Impact Factor
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    ABSTRACT: The biochemical changes taking place in human subjects following de-induction to plains from high altitude (5700-6100 m) after a prolonged slay of 9-13 months were investigated in 120 soldieri in four groups of 30 each on day 5, 30, 60 and 90 after their descent. One group of soldiers, who were never posted at high altitude served as control. Haemoglobin levels, which were initiallv hieh after 5 dnvs of de-induction droooed lo sienificantlv lower levels in the erouo , u . L ., " . studied on day 60 after de-induction. No clinically abnormal changes were noted in activities of serum enzymes, ie, aspartate aminotransferase, alanine aminotransferase and y-glutamyl transpeptidase. Alanine aminotransferase activity was found significantly elevated in 5-day group (53.1 i 0 . 2 4 IUII). Cholesterol and triglyceride levels were higher in 30-day group in comparison to groups studied on day 5,60 and 90 after de-induction from high altitude. Activity of glutathione S-transferase was more in groups studied on day 30 and 60 and may he in response to increased demand for detoxification of certain metabolites. Endogenous creatinine clearance was impaired with concomitant increase in serum creatinine levels. The creatinine clearance returned to normal only in group studied on day 90 after de-induction. Testosterone and estradiol levels were within normal physiological limits. However, there was increase in testosterone levels following ds-~nduction. Results of this cross-sectional study indicate that it takes 1-3 months after de-induction from high altitude for biochemical parameters to reach normal levels.
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    ABSTRACT: mins and minerals, for study of protective effects. After 15 days of exposure reduced and oxidised glutathione (GSH and GSSG), lipid peroxidation and enzymes, i.e. glutathione reductase (GR), glutathione peroxidase (GPx), gluta- thione S-transferase (GST), and γ γ γ γ-glutamyl transpeptidase (γ γ γ γ-GT) activities were measured in blood/erythrocytes and liver. There was a significant rise in blood GSSG level and a decrease in GSH/GSSG ratio, with increased lipid peroxidation in fluoride-exposed animals. A marked decrease in GR and GST activities and an increase in γ γ γ γ-glutamyl transpeptidase activity were also noted in blood of fluoride exposed animals. In the liver no significant changes in these variables were observed. Results indicate oxidative stress during fluoride exposure. Spirulina treatment was beneficial to some extent as a rich source of the antioxidant vitamin β β β β-carotene.