Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

BACKGROUND

Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories.

METHODS

We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5-19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI <18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For school-aged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference) and obesity (BMI >2 SD above the median).

FINDINGS

From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness.

INTERPRETATION

The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesity.

FUNDING

UK Medical Research Council, UK Research and Innovation (Research England), UK Research and Innovation (Innovate UK), and European Union.

Diminishing benefits of urban living for children and adolescents' growth and development

Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1-6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5-19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was <1.1 kg m-2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified.

Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions.

Height and body-mass index trajectories of school-aged children and adolescents from 1985 to 2019 in 200 countries and territories: a pooled analysis of 2181 population-based studies with 65 million participants

BACKGROUND

Comparable global data on health and nutrition of school-aged children and adolescents are scarce. We aimed to estimate age trajectories and time trends in mean height and mean body-mass index (BMI), which measures weight gain beyond what is expected from height gain, for school-aged children and adolescents.

METHODS

For this pooled analysis, we used a database of cardiometabolic risk factors collated by the Non-Communicable Disease Risk Factor Collaboration. We applied a Bayesian hierarchical model to estimate trends from 1985 to 2019 in mean height and mean BMI in 1-year age groups for ages 5-19 years. The model allowed for non-linear changes over time in mean height and mean BMI and for non-linear changes with age of children and adolescents, including periods of rapid growth during adolescence.

FINDINGS

We pooled data from 2181 population-based studies, with measurements of height and weight in 65 million participants in 200 countries and territories. In 2019, we estimated a difference of 20 cm or higher in mean height of 19-year-old adolescents between countries with the tallest populations (the Netherlands, Montenegro, Estonia, and Bosnia and Herzegovina for boys; and the Netherlands, Montenegro, Denmark, and Iceland for girls) and those with the shortest populations (Timor-Leste, Laos, Solomon Islands, and Papua New Guinea for boys; and Guatemala, Bangladesh, Nepal, and Timor-Leste for girls). In the same year, the difference between the highest mean BMI (in Pacific island countries, Kuwait, Bahrain, The Bahamas, Chile, the USA, and New Zealand for both boys and girls and in South Africa for girls) and lowest mean BMI (in India, Bangladesh, Timor-Leste, Ethiopia, and Chad for boys and girls; and in Japan and Romania for girls) was approximately 9-10 kg/m2. In some countries, children aged 5 years started with healthier height or BMI than the global median and, in some cases, as healthy as the best performing countries, but they became progressively less healthy compared with their comparators as they grew older by not growing as tall (eg, boys in Austria and Barbados, and girls in Belgium and Puerto Rico) or gaining too much weight for their height (eg, girls and boys in Kuwait, Bahrain, Fiji, Jamaica, and Mexico; and girls in South Africa and New Zealand). In other countries, growing children overtook the height of their comparators (eg, Latvia, Czech Republic, Morocco, and Iran) or curbed their weight gain (eg, Italy, France, and Croatia) in late childhood and adolescence. When changes in both height and BMI were considered, girls in South Korea, Vietnam, Saudi Arabia, Turkey, and some central Asian countries (eg, Armenia and Azerbaijan), and boys in central and western Europe (eg, Portugal, Denmark, Poland, and Montenegro) had the healthiest changes in anthropometric status over the past 3·5 decades because, compared with children and adolescents in other countries, they had a much larger gain in height than they did in BMI. The unhealthiest changes-gaining too little height, too much weight for their height compared with children in other countries, or both-occurred in many countries in sub-Saharan Africa, New Zealand, and the USA for boys and girls; in Malaysia and some Pacific island nations for boys; and in Mexico for girls.

INTERPRETATION

The height and BMI trajectories over age and time of school-aged children and adolescents are highly variable across countries, which indicates heterogeneous nutritional quality and lifelong health advantages and risks.

FUNDING

Wellcome Trust, AstraZeneca Young Health Programme, EU.

Dose dependent effects of oxytocin on cognitive defects and anxiety disorders in adult rats following acute infantile maternal deprivation stress

Maternal deprivation at an early age is a powerful stressor that causes permanent alterations in cognitive and behavioral functions during the later stages of life. We investigated the effects of oxytocin on cognitive defects and anxiety disorders caused by acute infantile maternal deprivation in adult rats. We used 18-day-old Wistar albino rats of both sexes. The experimental groups included control (C), maternally deprived (MD), maternally deprived and treated with 0.02 μg/kg oxytocin (MD-0.02 µg/kg oxy), maternally deprived and treated with 2 μg/kg oxytocin (MD-2 µg/kg oxy). When the rats were 60 days old, the open field (OF) and elevated plus maze (EPM) behavioral tests, and the Morris water maze (MWM) test for spatial learning and memory were performed. In addition, the number of neurons in the hippocampus, prefrontal cortex (PFC) and amygdala were determined using quantitative histology. We also measured vascular endothelial growth factor (VEGF) and brain-derived neurotrophic factor (BDNF) levels in the PFC. In both sexes, the MD group failed the learning test and the MD-2 μg/kg oxy group failed in the memory test. The MD-0.02 μg/kg oxy group spent more time in the open arm of the EPM device and their locomotor activities were greater in the OF test. The VEGF and BDNF levels in the PFC were higher in the MD-0.02 μg/kg oxy groups than the other maternally deprived groups (oxytocin ±). The number of PFC neurons was low in all male maternally deprived (oxytocin ±) groups, while the number of amygdala neurons was low in both female and male maternally deprived (oxytocin ±) groups. Male rats were more affected by maternal deprivation; administration of oxytocin had dose-dependent biphasic effects on learning, memory and anxiety.

Effects of voluntary and involuntary exercise on cognitive functions, and VEGF and BDNF levels in adolescent rats

Regular treadmill running during adolescence improves learning and memory in rats. During adolescence, the baseline level of stress is thought to be greater than during other periods of life. We investigated the effects of voluntary and involuntary exercise on the prefrontal cortex and hippocampus, vascular endothelial growth factor (VEGF), brain-derived neurotrophic factor (BDNF) levels, and spatial learning, memory and anxiety in adolescent male and female rats. The voluntary exercise group was given free access to a running wheel for 6 weeks. The involuntary exercise group was forced to run on a treadmill for 30 min at 8 m/min 5 days/week for 6 weeks. Improved learning was demonstrated in both exercise groups compared to controls. Neuron density in the CA1 region of the hippocampus, dentate gyrus and prefrontal cortex were increased. Hippocampal VEGF and BDNF levels were increased in both exercise groups compared to controls. In females, anxiety and corticosterone levels were decreased; BDNF and VEGF levels were higher in the voluntary exercise group than in the involuntary exercise group. The adolescent hippocampus is affected favorably by regular exercise. Although no difference was found in anxiety levels as a result of involuntary exercise in males, females showed increased anxiety levels, and decreased VEGF and BDNF levels in the prefrontal cortex after involuntary exercise.

Short-term melatonin treatment improved diabetic nephropathy but did not affect hemorheological changes in diabetic rats

Increased oxidative stress and hemorheological disturbances may play very important roles in the development of microangiopathies in diabetes mellitus. This study was designed to determine the healing effect of melatonin on hemorheological parameters and diabetic nephropathy in streptozotocin (STZ)-induced diabetic rats. Wistar male rats were divided into four groups as control, untreated-diabetic, melatonin-treated control and melatonin-treated diabetic rats. Diabetes was induced by injecting streptozotocin (45 mg/kg, i.p.). Fourteen weeks after inducement of diabetes, melatonin (10 mg/kg) was administered intraperitoneally for 5 days to the rats. Erythrocyte deformability and aggregation were measured by laser differaction analysis (LORCA). Diabetic nephropathy was assessed by histopathologic evaluation and TUNEL stain in the diabetic kidney. Decreased erythrocyte deformability and increased erythrocyte aggregation indices were determined in the diabetic group. Melatonin treatment did not improve these hemorheological abnormalities. However, renal injuries were diminished in the melatonin-treated diabetic group compared to the untreated diabetic group. Also, melatonin had an antiapoptotic effect on the diabetic kidney. It was concluded that i.p. administration of melatonin for 5 days improved renal injury in diabetic rats, probably by decreasing oxidative stress, but did not affect hemorheological changes.

Plasma levels of nitrites, PGF1α and nitrotyrosine in LPS-treated rats: functional and histochemical implications in aorta

We investigated the effects of lipopolysaccharide (LPS) administration on plasma nitrite, nitrotyrosine and 6-keto prostaglandin F1alpha, (PGF1alpha) levels and the related resultant changes in function and histochemistry of aorta in rats. Plasma nitrite and PGF1alpha nitrotyrosine levels were analysed after 5 mg/kg intravenous LPS was administered to rats compared with those in non-treated rats. The distribution of nitrotyrosine in the aorta was studied immunohistochemically. The contractile responses of aortic rings to phenylephrine (PE) from both the LPS-treated and control rats were studied in the organ baths. There were increases in plasma nitrite, PGF1alpha, and nitrotyrosine concentrations of LPS-treated rats compared to non-treated rats. Immunoreactivity of nitrotyrosine residues were detected in the endothelial and smooth muscle cells in LPS-treated but not in control rat aorta. The contractile responses to PE of the LPS-treated rat aortic rings were significantly reduced as compared with those of control rat's. Incubation of the aortic rings from LPS-treated rats with cyclooxygenase inhibitor indomethacine or with a combination of indomethacine and nitric oxide synthase inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME) increased the contractile responses to the levels observed in control rats suggesting that both prostanoids and particularly nitric oxide (NO) are involved in the reduced contractile responses in LPS-treated rats. These results supported the view that LPS might cause an increment in both NO and PGI2 levels. This increase in the NO and PGI2 levels may be responsible from the reduction in responses of aorta to contractile agents in LPS-treated rats. Increased peroxynitrite formation in LPS-treated rats may lead to nitration of the tyrosil residues of the proteins in the aorta.

Deprenyl and the relationship between its effects on spatial memory, oxidant stress and hippocampal neurons in aged male rats

Oxidative stress may play a major role in the aging process and associated cognitive decline. Therefore, antioxidant treatment may alleviate age-related impairment in spatial memory. Cognitive impairment could also involve the age-related morphological alterations of the hippocampal formation. The aim of this study was to examine the relationship between the effects of deprenyl, an irreversible monoamine-oxidase B inhibitor, on spatial memory by oxidant stress and on the total number of neurons in the hippocampus CA1 region of aged male rats. In this study, 24-month-old male rats were used. Rats were divided into control and experimental groups which received an injection of deprenyl for 21 days. Learning experiments were performed for six days in the Morris water maze. Spatial learning was significantly better in deprenyl-treated rats compared to saline-treated rats. Deprenyl treatment elicited a significant decrease of lipid peroxidation in the prefrontal cortex, striatum and hippocampus regions and a significant increase of glutathione peroxidase activity in the prefrontal cortex and hippocampus. It was observed that deprenyl had no effect on superoxide dismutase activity. The total number of neurons in the hippocampus CA1 region was significantly higher in the deprenyl group than in the control group. In conclusion, we demonstrated that deprenyl increases spatial memory performance in aged male rats and this increase may be related to suppression of lipid peroxidation and alleviation of the age-related decrease of the number of neurons in the hippocampus. The results of such studies may be useful in pharmacological alleviation of the aging process.

Effects of melatonin on oxidative stress and spatial memory impairment induced by acute ethanol treatment in rats

Melatonin has recently been suggested as an antioxidant that may protect neurons from oxidative stress. Acute ethanol administration produces both lipid peroxidation as an indicator of oxidative stress in the brain and impairs water-maze performance in spatial learning and memory tasks. The present study investigated the effect of melatonin against ethanol-induced oxidative stress and spatial memory impairment. The Morris water maze was used to evaluate the cognitive functions of rats. Thiobarbituric acid reactive substances (TBARS), which are the indicators of lipid peroxidation, and the activities of antioxidative enzymes (glutathione peroxidase and superoxide dismutase) were measured in the rat hippocampus and prefrontal cortex which form interconnected neural circuits for spatial memory. Acute administration of ethanol significantly increased TBARS levels in the hippocampus. Combined melatonin-ethanol treatment caused a significant increase in glutathione peroxidase activities and a significant decrease of TBARS in the rat hippocampus. In the prefrontal cortex, there was only a significant decrease of TBARS levels in the combined melatonin-ethanol receiving group as compared to the ethanol-treated group. Melatonin did not affect the impairment of spatial memory due to acute ethanol exposure, but melatonin alone had a positive effect on water maze performances. Our study demonstrated that melatonin decreased ethanol-induced lipid peroxidation and increased glutathione peroxidase activity in the rat hippocampus.

Effect of melatonin on brain oxidative damage induced by traumatic brain injury in immature rats

Progressive compromise of antioxidant defenses and free radical-mediated lipid peroxidation, which is one of the major mechanisms of secondary traumatic brain injury (TBI), has also been reported in pediatric head trauma. In the present study, we aimed to demonstrate the effect of melatonin, which is a potent free radical scavenger, on brain oxidative damage in 7-day-old rat pups subjected to contusion injury. Whereas TBI significantly increased thiobarbituric acid reactive substances (TBARS) levels, there was no compensatory increase in the antioxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GPx) 24 hours after TBI in 7-day-old rats. Melatonin administered as a single dose of 5 mg/kg prevented the increase in TBARS levels in both non-traumatized and traumatized brain hemispheres. In conclusion, melatonin protects against oxidative damage induced by TBI in the immature brain.

Effects of acute footshock stress on antioxidant enzyme activities in the adolescent rat brain

In a previous study we demonstrated that acute footshock stress increased glutathione peroxidase activity in the prefrontal cortex and striatum of adult male rats. Adolescents may respond differently to stress as life stressors may be greater than at other ages. The present study examined the effects of the acute footshock stress on superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzyme activities and thiobarbituric acid reactive substances (TBARS) levels in adolescent male and female rat brains. We demonstrated that acute footshock stress increased SOD activity in the prefrontal cortex, and increased GPx activity in the hippocampus in female rats. In males, acute footshock stress increased GPx activity in the prefrontal cortex and hippocampus. Footshock stress did not change TBARS levels. These results indicate a strong role of gender in the response of adolescent subjects to various aspects of stress.

Effect of melatonin on brain oxidative damage induced by traumatic brain injury in immature rats

Progressive compromise of antioxidant defenses and free radical-mediated lipid peroxidation, which is one of the major mechanisms of secondary traumatic brain injury (TBI), has also been reported in pediatric head trauma. In the present study, we aimed to demonstrate the effect of melatonin, which is a potent free radical scavenger, on brain oxidative damage in 7-day-old rat pups subjected to contusion injury. Whereas TBI significantly increased thiobarbituric acid reactive substances (TBARS) levels, there was no compensatory increase in the antioxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GPx) 24 hours after TBI in 7-day-old rats. Melatonin administered as a single dose of 5 mg/kg prevented the increase in TBARS levels in both non-traumatized and traumatized brain hemispheres. In conclusion, melatonin protects against oxidative damage induced by TBI in the immature brain.

Effects of acute footshock stress on antioxidant enzyme activities in the adolescent rat brain

In a previous study we demonstrated that acute footshock stress increased glutathione peroxidase activity in the prefrontal cortex and striatum of adult male rats. Adolescents may respond differently to stress as life stressors may be greater than at other ages. The present study examined the effects of the acute footshock stress on superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzyme activities and thiobarbituric acid reactive substances (TBARS) levels in adolescent male and female rat brains. We demonstrated that acute footshock stress increased SOD activity in the prefrontal cortex, and increased GPx activity in the hippocampus in female rats. In males, acute footshock stress increased GPx activity in the prefrontal cortex and hippocampus. Footshock stress did not change TBARS levels. These results indicate a strong role of gender in the response of adolescent subjects to various aspects of stress.

Effects of melatonin on oxidative stress and spatial memory impairment induced by acute ethanol treatment in rats

Melatonin has recently been suggested as an antioxidant that may protect neurons from oxidative stress. Acute ethanol administration produces both lipid peroxidation as an indicator of oxidative stress in the brain and impairs water-maze performance in spatial learning and memory tasks. The present study investigated the effect of melatonin against ethanol-induced oxidative stress and spatial memory impairment. The Morris water maze was used to evaluate the cognitive functions of rats. Thiobarbituric acid reactive substances (TBARS), which are the indicators of lipid peroxidation, and the activities of antioxidative enzymes (glutathione peroxidase and superoxide dismutase) were measured in the rat hippocampus and prefrontal cortex which form interconnected neural circuits for spatial memory. Acute administration of ethanol significantly increased TBARS levels in the hippocampus. Combined melatonin-ethanol treatment caused a significant increase in glutathione peroxidase activities and a significant decrease of TBARS in the rat hippocampus. In the prefrontal cortex, there was only a significant decrease of TBARS levels in the combined melatonin-ethanol receiving group as compared to the ethanol-treated group. Melatonin did not affect the impairment of spatial memory due to acute ethanol exposure, but melatonin alone had a positive effect on water maze performances. Our study demonstrated that melatonin decreased ethanol-induced lipid peroxidation and increased glutathione peroxidase activity in the rat hippocampus.

Antioxidant enzyme levels in intestinal and renal tissues after a 60-minute exercise in untrained mice

The present study was designed to determine the effects of exercise on the antioxidant enzymatic system and lipid peroxidation in small intestine and kidney, during the post-exercise period in untrained mice. Two days after the last adaptation running exercise, animals were ran on the treadmill for 60 min at 18 m/min. 5 degrees slope. After the acute exercise the animals were killed by cervical dislocation, immediately (0 h), 3 hours (3 h) and 24 hours (24 h) after the exercise. Control animals were killed without running exercise. Their proximal small intestinal and renal tissues were quickly removed. Changes in the concentration of thiobarbituric acid reactive substance (TBARS), as an index of lipid peroxidation, in intestine and kidney were studied in mice after the running exercise and in unexercised control group. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) were determined in these tissues. Tissue SOD, GPx activities and TBARS level were not increase by the exercise in kidney. Intestinal SOD activity decreased after exercise (0 h and 3 h respectively, p<0.05, p<0.01) and retumed to control levels. Intestinal GPx activity increased after exercise (0 h, p<0.05) and returned to control levels. There was no significant difference among groups in intestinal tissue TBARS levels. These findings could suggest that submaximal exercise may not cause oxidative stress in proximal small intestinal tissue and kidney.

Pentoxifylline contributes to the hepatic cytoprotective process in rats undergoing hepatic ischemia and reperfusion injury

AIM

Considerable efforts have been made to find and/or eliminate the underyling causes of hepatic ischemia-reperfusion injury, but many points are still unclear. Pentoxifylline-related cytoprotection is one of these unclear points. Our study tests the effects of pentoxifylline on the hepatic cytoprotective process in an experimental model.

MATERIALS AND METHODS

The animals were divided into two groups: (1) placebo-pretreated rats and (2) pentoxifylline-pretreated rats. After pretreatment, all rats underwent the hepatic ischemia-reperfusion procedure which was performed by clamping the hepatoduodenal ligament. To evaluate the liver injury, serum levels of alanine transaminase (ALT) and aspartate transaminase (AST), and liver tissue levels of prostaglandin E(2) (PGE(2)) were measured before ischemia, immediately after ischemia and immediately after reperfusion.

RESULTS

Before ischemia and immediately after ischemia, there were no significant differences between ALT and AST levels of groups 1 and 2 (p >0.05). However, at the end of reperfusion, ALT and AST levels of group 2 were significantly decreased when compared with group 1 (p < 0.05 and p < 0.01, respectively). Additionally, tissue levels of PGE(2) that were obtained before ischemia, immediately after ischemia and immediately after reperfusion in group 2 were significantly higher than those of group 1 (p < 0.001).

CONCLUSION

Pentoxifylline reduces reperfusion injury of the liver through significantly decreased transaminase levels, and contributes to hepatic cytoprotection by increasing tissue levels of PGE(2) significantly. These effects reflect the role of tissue PGE(2) in pentoxifylline-related hepatoprotection against ischemia-reperfusion injury of the liver.

Methamphetamine causes depletion of glutathione and an increase in oxidized glutathione in the rat striatum and prefrontal cortex

The administration of methamphetamine to experimental animals results in damage to dopaminergic neurons. The hypothesis that methamphetamine-induced neurotoxicity is mediated by reactive oxygen species was evaluated. It was found that acute administration of methamphetamine (5 and 15 mg kg(-1)) resulted in production of oxidative stress as demonstrated by decreased glutathione and increased oxidized glutathione levels in the rat striatum and prefrontal cortex. These changes in glutathione and oxidized glutathione levels were dose-dependent in striatum but not in prefrontal cortex. In conclusion, the results of present study provide further evidence in support of the notion that oxidative stress may play an important role in the methamphetamine-induced neurotoxicity.

Lipid peroxidation and antioxidant enzyme levels of intestinal renal and muscle tissues after a 60 minutes exercise in trained mice

To investigate the effect of blood perfusion difference on oxidant status, mice were trained by a 7-week running program. Two days after the last training session, mice were exercised for 60 minutes at the same training intensity. Changes in the concentration of thiobarbituric acid reactive substance (TBARS), as an index of lipid peroxidation, in intestine, kidney and muscle, were studied in trained mice immediately (0 h), 3 h and 24 h after the running exercise and in unexercised control group. The activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) and xanthine oxidase (XO) were determined in these tissues. Tissue SOD activities were unaffected by the exercise. Muscle GPx activity increased after exercise (0 h and 3 h group, P < 0.01) and returned to control levels at 24 h, but there was not any significant difference in intestinal and renal tissues. Renal tissue XO activity could not be determined. There was not any significant difference among groups in intestinal tissue XO activity. The activity of XO was decreased only in skeletal muscle at 0 h (P < 0.05). TBARS levels of exercised groups were higher than control in muscle (P < 0.01). Intestinal TBARS levels decreased at 0 h (P < 0.05), than reached to control level. Renal TBARS levels of 0 h and 24 h group was higher than control (P < 0.01, P < 0.01 respectively). The results show that a long distance running exercise may cause lipid peroxidation damage in skeletal muscle and kidney.

The effects of single dose of methamphetamine on lipid peroxidation levels in the rat striatum and prefrontal cortex

The administration of methamphetamine to experimental animals results in damage to dopaminergic neurons. In the present study, we demonstrated that a single dose (15 mg/kg) of methamphetamine results in production of oxidative stress as demonstrated by increased thiobarbituric acid reactive substances levels in the rat striatum and prefrontal cortex. In conclusion, the results of present study provide further evidence in support of the notion that oxidative stress may play an important role in the methamphetamine-induced neurotoxicity.

Effects of footshock stress on superoxide dismutase and glutathione peroxidase enzyme activities and thiobarbituric acid reactive substances levels in the rat prefrontal cortex and striatum

Mild footshock stress results in an increase dopamine metabolism in the prefrontal cortex. Increases in either the intensity or duration of stress enhance dopamine metabolism in the nucleus accumbens and striatum, as well as in the prefrontal cortex. Dopamine is metabolized by monoamine oxidase with hydrogen peroxide as a product. In this study we have demonstrated that while very mild (0.2 mA) footshock stress did not change glutathione peroxidase activity in the rat prefrontal cortex and striatum, more intense (1.6 mA) footshock stress increased glutathione peroxidase activity at 0, 15, 30 and 60 min after the footshock in the prefrontal cortex and at 30 min after the footshock in the striatum. Stress did not change superoxide dismutase activity and thiobarbituric acid reactive substances levels. These results indicate that increased dopamine metabolism induced by footshock stress is probably responsible for the increase of glutathione peroxidase activity.

Prophylactic ranitidine in experimental fetal distress: acute phase effects on the fetal stomach

Fetal distress (FD) adversely affects fetal gastric physiology and histology, increasing gastric acid secretion and disturbing gastric protective mechanism. Considering these findings, an experimental study was planned to test whether ranitidine prevents FD-related gastric physiological and histological changes during late gestational period. In this study, a rabbit model of FD was created by way of intermittent maternal aortic occlusion. In group 1 (SC), saline treated animals underwent control operation. In group 2 (SD), FD was created in saline treated animals. In group 3 (RC), ranitidine treated animals underwent control operation. In group 4 (RD), FD was created in ranitidine treated animals. Blood lactic acid levels of the fetuses were 2.3 +/- 1.0 mg/L in SC group and 4.7 +/- 1.8 mg/L in group SD (p < 0.01); 2.5 +/- 0.9 mg/L in group RC and 6.7 +/- 2.5 mg/L in group RD (p < 0.01). Fetal gastric acid secretion was 5.94 +/- 2.13 microEq/h in group SC and 8.26 +/- 2.24 microEq/h in group SD (p < 0.05); 6.63 +/- 2.3 microEq/h in group RC and 6.04 +/- 2.43 microEq/h in group RD (p < 0.05). Fetal gastric PGE2 level was 16.4 +/- 2.65 microg/g-wet weight in group SC and 7.62 +/- 1.86 microg/g-wet weight in group SD (p < 0.01); 15.6 +/- 2.61 microg/g-wet weight in group RC and 8.44 +/- 1.44 microg/g-wet weight in group RD (p < 0.01). In addition, histopathological examination showed normal gastric structure in groups SC and RC, but there were mild erosive and hemorrhagic changes in groups SD and RD. Because prophylactic ranitidine significantly decreased gastric acid secretion, but did not prevent harmful histopathologic effects in FD, it is suggested that gastric damage cannot be avoided by decreasing gastric acid secretion alone. However PGE2 analogs with or without H2 receptor blockers may have a potential role to prevent FD-related gastric damage.

Methamphetamine causes lipid peroxidation and an increase in superoxide dismutase activity in the rat striatum

The administration of methamphetamine to experimental animals results in damage to nigrostriatal dopaminergic neurons. In the present study, we demonstrated that both the acute repeated and the chronic administration of methamphetamine causes an increase in thiobarbituric acid reactive substances, which are indicators of lipid peroxidation, and superoxide dismutase activity in the rat striatum. The results of present study strengthen the notion that reactive oxygen species may play an important role in the methamphetamine-induced neurotoxicity.

Acute physiopathological and histopathological effects of fetal distress on the fetal stomach: an experimental study

Although effects of stress on the stomach have been extensively investigated in children and adults, our knowledge about effects of fetal distress (FD) on the fetal stomach is quite limited. Therefore, an experimental study was planned to evaluate the effects of FD on fetal gastric physiology and histology. In this study, a model of FD was created by way of intermittent maternal aortic occlusion in pregnant rabbits. In total, 21 fetuses of 6 pregnant rabbits were available for surgical and laboratory procedures. Laboratory examinations showed that (1) fetal gastric acid secretion was 4.24 +/- 2.68 muEq/h in the control group and 18.08 +/- 6.34 muEq/h in the distress group (p < 0.01) and (2) fetal gastric PGE2 level was 16.59 +/- 6.15 mg/g wet weight in the control group and 9.86 +/- 3.46 mg/g wet weight in the distress group (p < 0.05). Histopathologically, there were mild hemorrhagic and errosive changes in the distressed fetuses, but not in control fetuses. These findings support that FD adversely affects fetal gastric physiology through two mechanisms consisting of increased gastric acid secretion and decreased fetal gastric protection in rabbits. Consequently, gastric injury should be noted as a potential problem among hypoxia-associated abnormalities encountered in the distressed fetus.