Metabolic Responses to High-Fat Feeding and Chronic Psychological Stress Combination.

INTRODUCTION: High-fat diet (HFD) consumption and being exposed to daily psychological stress, common environmental factors in modern lifestyle, play an important role on metabolic disorders such as glucose homeostasis impairment. The aim of this study was to investigate the effects of high-fat diet (HFD) and psychological stress combination on metabolic response to chronic psychological stress in male rats. METHOD: Male Wistar rats were divided into HFD, and normal diet (ND) groups and then into stress and nonstress subgroups. The diets were applied for 5 weeks, and psychological stress was induced for 7 consecutive days. Then, blood samples were taken to measure glucose, insulin, free fatty acids (FFA), and leptin and corticosterone concentrations. Subsequently, glucose-stimulated insulin release from pancreatic isolated islets was assessed. RESULTS: HFD did not significantly change fasting plasma glucose, insulin and corticosterone levels, whereas increased plasma leptin (7.05 ± 0.33) and FFA (p < 0.01) levels and impaired glucose tolerance. Additionally, HFD and stress combination induced more profound glucose intolerance associated with increased plasma corticosterone (p < 0.01) and leptin (8.63 ± 0.38) levels. However, insulin secretion from isolated islets did not change in the presence of high-fat diet and/or stress. CONCLUSION: HFD should be considered as an intensified factor of metabolic impairments caused by chronic psychological stress.

Treadmill exercise with nanoselenium supplementation affects the expression of Irisin/FNDC5 and semaphorin 3A in rats exposed to cigarette smoke extract.

In the current study, we investigated the impacts of 6 weeks of aerobic interval training (AIT) with selenium nanoparticles (SeNPs) on muscle, serum, and lung irisin (FNDC5) and Sema3A in rats exposed to cigarette smoke extract (CSE). To this end, 49 male Wistar rats (8 weeks old) were divided into seven groups: control, SeNPs (2.5 mg/kg b.w by oral gavage, 3 days/week, 6 weeks), AIT (49 min/day, 5 days/week for 6 weeks, interval), SeNPs + AIT, CSE (150 µL by IP injection, 1 day/week for 6 weeks), CSE + AIT, and CSE + SeNPs + AIT. The CSE group showed a significant reduction in irisin and Sema3A serum levels, as well as a decrease in FNDC5 and Sema3A gene expression in lung tissue (p < 0.05). A combined treatment (AIT with SeNPs) significantly increased the serum level and the expression of muscle and lung irisin (FNDC5) and Sema3A in CSE received groups (p < 0.05). There was a positive and significant correlation between muscle FNDC5 and lung FNDC5 in the CSE + SeNPs + AIT group (r = 0.92, p = 0.025). In addition, there was a positive and significant correlation between serum Sema3A and lung Sema3A of CSE + SeNPs + AIT group (r = 0.97, p = 0.004). Seemingly, performing aerobic exercises with the antioxidant and anti-inflammatory supplement nano-selenium in the model of lung damage (similar to COPD) can boost myokine irisin and Sema3A, especially in serum and lung tissue. These results displayed the paracrine/endocrine regulatory function of these myokines on other tissues. In other words, these interventions emphasized the creation of crosstalk between skeletal muscles and damaged lung, focusing on its recovery; however, further research is needed.

The effect of 24-hour sleep deprivation and anaerobic exercise on the expression of BAX, BCL2, BMAL1 and CCAR2 genes in peripheral blood mononuclear cells after L-arginine supplementation.

Sleep deprivation disrupt the circadian clock and exercise performance. Defective oxidative stress caused by sleep deprivation may affect the expression of genes involved in cell apoptosis. Since a number of studies have shown the anti-apoptotic effect of L-arginine, so the aim of this study was to evaluate the effect of eight weeks of L-arginine supplementation on the expression of brain and muscle ARNT-like protein 1 (BMAL1), cell cycle and apoptosis regulator 2 (CCAR2), and BAX and BCL2 genes during sleep deprivation and acute anaerobic exercise. Participants included 20 healthy men age 26-35 years, randomized into the L-arginine intervention group (n = 10) and a placebo control (n = 10). The running-based anaerobic sprint test (RAST) was used for anaerobic exercise. Intervention subjects took one 1000 mg L-arginine tablet daily for 8 weeks. The Real-Time PCR method was used to determine apoptosis gene expression in peripheral blood mononuclear cells (PBMCs). Acute anaerobic exercise and sleep deprivation both increased the expression of BAX and CCAR2 genes, and decreased the expression of BCL2 and BMAL1 genes (p < 0.05 for all). L-arginine supplementation increased the expression of BMAL1 and BCL2 genes and decreased the expression of BAX and CCAR2 genes relative to control (p < 0.05). L-Arginine controlled the increase in expression of BAX and CCAR2 genes and the decrease in expression of BCL2 and BMAL1 genes in response to sleep deprivation and acute anaerobic exercise (p < 0.05). Our results showed that 24-hour sleep deprivation and acute anaerobic exercise increased the expression of pro-apoptotic genes (BAX and CCAR2) and decreased the expression of anti-apoptotic genes (BCL2 and BMAL1), although the effect of sleep deprivation is greater. In this situation, L-arginine supplementation may balance the apoptotic state of peripheral blood mononuclear cells. However, any recommendation about this needs further research.

Irisin/FNDC5 influences myogenic markers on skeletal muscle following high and moderate-intensity exercise training in STZ-diabetic rats.

In the present study, we investigated the effects of high-intensity interval training (HIIT) versus moderate-intensity continuous training (MICT) on irisin and expression of myogenic markers (paired box 7 (Pax7), myogenic differentiation 1 (MyoD), myogenin) in skeletal muscle of diabetic rats. Eighty-four male Wistar rats (6 weeks of age) were randomly divided into seven groups (n = 12): basic control (Co Basic), 8 weeks control (Co 8w), diabetes mellitus (DM), HIIT, DM + HIIT, MICT, and DM + MICT groups. Diabetes was induced by intraperitoneal injection of streptozotocin (STZ). The V ˙ o 2 max protocol was characterized by running on a rodent treadmill with moderate intensity (60-70% V ˙ o 2 max ), 60 min per session, 5 days/week, for 6 weeks. HIIT consisted of six 3-min runs at a high intensity (80-90% V ˙ o 2 max ) alternated with 2-min running at low intensity (50% V ˙ o 2 max ), 30 min per session, 5 days/week, for 6 weeks. Results showed that DM decreased myoblast markers compared to Co Basic and Co 8w groups. Fibronectin type III domain-containing protein 5 (FNDC5) mRNA decrease was correlated with myoblast markers (Pax7 r = 0.632, p = 0.027; MyoD r = 0.999, p = 0.001; myogenin r = 1.000, p = 0.001) in DM group. DM + MICT significantly increased gene expression of MyoD, myogenin, and FNDC5 compared to DM and DM + HIIT. The results also showed that the intensity and duration of exercise on the treadmill were effective in stimulating irisin and myogenic markers after DM.

Comparative effects of high-intensity interval training and moderate-intensity continuous training on soleus muscle fibronectin type III domain-containing protein 5, myonectin and glucose transporter type 4 gene expressions: a study on the diabetic rat model.

BACKGROUND: The increase in fibronectin type-III domain-containing protein 5 (FNDC5), myonectin, and glucose transporter 4 (GLUT4) leads to a decrease in diabetes; meanwhile, exercise training can affect these factors. The result regarding the comparison between the effect of high-intensity interval training (HIIT) and that of moderate-intensity continuous training (MICT) is confusing. Thus, the present study investigated the comparative effects of HIIT and MICT on soleus muscle FNDC5, myonectin, and GLUT4 gene expressions in the diabetic rat model. METHODS AND RESULTS: Seventy-two male Wistar rats (weight 200 g ± 20) were randomly and equally assigned to six groups: control-healthy, MICT-healthy, HIIT-healthy, control-diabetes, MICT-diabetes, and HIIT-diabetes. At the first level, Streptozotocin (STZ) was utilized to induce diabetes in rats (at a dose of 55 mg/kg). After that, the training groups performed HIIT and MICT programs on the rodent treadmill for 6 weeks (five-session/week). Twenty-four hours after the last intervention, soleus muscle was removed, and sent to a research facility for future examinations. HIIT and MICT increased the muscle FNDC5, myonectin, and GLUT4 gene expression compared to the control group (P < 0.05). The type of training had no significant effect on the FNDC5 (P > 0.05), while the MICT program induced a greater increase in the myonec ztin and GLUT4 compared to the HIIT program (P < 0.05). Meanwhile, a positive relationship between all variables was observed. CONCLUSIONS: Exercise training has a beneficial effect on diabetes conditions via the effect of FNDC5, myonectin, and GLUT4. Due to the correlation between myonectin and GLUT4 shown in the present study, physical activity may alter myonectin through its effect on GLUT requiring further investigation by subsequent studies.

Potential role of Nigella sativa supplementation with physical activity in prophylaxis and treatment of COVID-19: a contemporary review.

The widespread prevalence and mortality of coronavirus diseases-2019 (COVID-19) lead many researchers to study the SARS-CoV-s2 infection to find a treatment for this disease. Discovering the mechanisms of action of COVID-19 and coping at the cellular level with this disease can have better effects. Including the target tissues of this disease are the lungs and the immune system. It is stated that COVID-19 easily infiltrates into alveoli through its receptors and then starts to proliferate. Subsequently, with the weakening of immune cells and increase inflammatory cytokines, it increases the rate of inflammation in the body. Strengthening the immune system and inhibiting COVID-19 receptors can play a preventive or even therapeutic role for this disease. Nigella sativa (N. sativa) is one of the herbal medicines to possess numerous pharmacological effects related to several organs of the body. Among the extraordinary properties of this plant is improving asthma and several lung diseases. The recent studies have shown that N. sativa at the cellular level can inhibit COVID-19 receptors. It was also stated that performing regular exercise training (especially moderate-intensity exercise training) can modulate the immune system and have an anti-inflammatory effect. Since the use of herbal supplements with exercise can have tremendous therapeutic effects at the cellular level, the hypothesis to use the Nigella sativa along with exercise training to prophylaxis and treatment COVID-19 will be highlighted in this paper.

The effects of high-intensity interval training on reverse cholesterol transport elements: A way of cardiovascular protection against atherosclerosis.

AIMS: Reverse cholesterol transport (RCT) is a process that prevents atherosclerosis. Studies showed that exercise training for strengthening cardiac muscle, increasing heart lipid metabolism and its potency against risk factors could protect cardiovascular health. Thus, the present study aims to investigate the effects of high intensity interval training (HIIT) on RCT and its related elements in plasma and tissues (liver and intestine) of rats. MATERIALS AND METHODS: Twenty adult male Wistar rats were randomly divided into control (n = 10) and trained (n = 10) groups. The trained group undertook HIIT (90%-95% of VO2max, five days/week, for 10 weeks) on a treadmill. The rats were killed five days after the last training session to minimize the effects of the last training session. KEY FINDINGS: A higher and significant ABCA1 mRNA was observed in the liver and intestine of trained rats. However, ABCG1 and LXR expressions only increased in the liver following the HIIT. These changes in the expression of the trained rats were accompanied by higher changes in plasma LCAT and HDL levels. SIGNIFICANCE: The responses of ABCA1, as a key player in plasma HDL biogenesis, are similar in liver and intestine tissues after the HIIT program. However, different responses of ABCG1 and LXR in the liver and intestine tissues of the trained rats confirm the main role of the liver than the intestine in HDL biogenes. Therefore, HIIT modality result in cardiovascular protection by increasing the expression of genes involved in RCT and biogenesis of HDL.

High-fat diet effects on metabolic responses to chronic stress.

CONTEXT: High-fat diets and chronic stress are prevalent risk factors for various chronic diseases in modern societies. OBJECTIVE: This study investigated the effect of high-fat diet on glucose-related metabolic responses to chronic foot-shock stress. MATERIALS AND METHODS: Male rats were divided into high-fat diet (containing 54.21% saturated and 44.89% unsaturated fatty acids) and normal diet groups and then into stress and non-stress subgroups. The diets were applied for 5 weeks, and stress was induced during the last week of the diet course. Plasma levels of metabolic parameters, HOMA-IR index, intra-abdominal fat weight, and islets' insulin secretion were assessed. RESULTS: High-fat diet increased abdominal fat weight and plasma leptin, and insulin levels in response to stress without affecting HOMA-IR index and islets' insulin secretion. CONCLUSIONS: High proportion of unsaturated fat may not lead to deleterious metabolic responses; however combined with chronic stress has a synergistic and adverse effect on visceral adiposity and results in elevated plasma leptin.

Stress increased ghrelin secretion from pancreatic isolated islets in male rats.

It has been demonstrated that plasma ghrelin is likely affected by stress, but little attention has been paid to the effect of stress on ghrelin release from pancreatic islets. This study investigates the effect of stress on ghrelin secretion from pancreatic islets in rats. Male Wistar rats were divided into control and stressed groups. The stressed group was further divided into foot-shock and psychological stress subgroups. Stress was induced by a communication box. After stress exposure, blood sampling was performed to determine the plasma levels of corticosterone, glucose, and ghrelin. Then the animals' pancreatic islets were isolated to assess their ghrelin output at 5.6, 8.3, and 16.7 mM glucose concentrations. Acute exposure to foot-shock and psychological stress both increased plasma corticosterone concentration. Moreover, plasma glucose concentration increased in the foot-shock stress group. Chronic exposure to foot-shock decreased plasma ghrelin concentration, whereas acute exposure had no significant effect. Acute and chronic exposure to foot-shock and psychological stress increased ghrelin secretion from isolated islets in the presence of different glucose concentrations. The results of the present study suggest that ghrelin secretion from isolated islets is not glucose-dependent. However, ghrelin secretion appears to be intensely responsive to both acute and chronic stress.

Addressing the sexual problems of Iranian women in a primary health care setting: A quasi-experimental study.

BACKGROUND: The World Health Organization emphasizes on integration of sexual health into primary health care services, educating people and health care workers about sexuality, and promoting optimal sexual health. Despite the high prevalence of sexual problems, these problems are poorly managed in primary health care services. This study was conducted to evaluate the efficacy and feasibility of the first two steps of PLISSIT (Permission, Limited Information, Specific Suggestions, Intensive Treatment) model for handling of women sexual problems in a primary health care setting. MATERIALS AND METHODS: This was a quasi-experimental study that was carried out in Zanjan, northwest of Iran. Eighty women who had got married in the past 5 years and had sexual problem were randomly assigned to control and intervention groups. The intervention group received consultation based on PLISSIT model by a trained midwife and the control group received routine services. Female Sexual Function Index (FSFI) questionnaire was used for assessing and tracking any changes in sexual function. Data were collected at three points: Before consultation and 2 and 4 weeks after consultation. Paired t-test and repeated measures analysis of variance (ANOVA) test were used for comparison of scores within groups. RESULTS: Significant improvement was found in FSFI sub-domain scores, including sexual desire (P < 0.0001), arousal (P < 0.0001), lubrication (P < 0.0001), orgasm (P = 0.005), satisfaction (P = 0.005), pain (P < 0.0001), and FSFI total score (P < 0.0001) in the intervention group compared to the control group. CONCLUSIONS: This study showed that PLISSIT model can meet the sexual health needs of clients in a primary health care setting and it can be used easily by health workers in this setting for addressing sexual complaints and dysfunctions.

Effect of early life stress on pancreatic isolated islets' insulin secretion in young adult male rats subjected to chronic stress.

Early stressful experiences may predispose organisms to certain disorders, including those of metabolic defects. This study aimed to explore the effects of early life stress on pancreatic insulin secretion and glucose transporter 2 (GLUT2) protein levels in stressed young adult male rats. Foot shock stress was induced in early life (at 2 weeks of age) and/or in young adulthood (at 8-10 weeks of age) for five consecutive days. Blood samples were taken before and after stress exposure in young adult rats. At the end of the experiment, glucose tolerance, isolated islets' insulin secretion, and pancreatic amounts of GLUT2 protein were measured. Our results show that early life stress has no effect on basal plasma corticosterone levels and adrenal weight, either alone or combined with young adulthood stress, but that early life + young adulthood stress could prevent weight gain, and cause an increase in basal plasma glucose and insulin. The homeostasis model assessment of insulin resistance index did not increase, when the rats were subjected to early life stress alone, but increased when combined with young adulthood stress. Moreover, glucose tolerance was impaired by the combination of early life + young adult stress. There was a decrease in islet's insulin secretion in rats subjected to early life stress in response to 5.6 mM glucose concentration, but an increase with a concentration of 16.7 mM glucose. However, in rats subjected to early life + young adulthood stress, islet's insulin secretion increased in response to both the levels of glucose concentrations. GLUT2 protein levels decreased in response to early life stress and early life + young adulthood stress, but there was a greater decrease in the early life stress group. In conclusion, perhaps early life stress sensitizes the body to stressors later in life, making it more susceptible to metabolic syndrome only when the two are in combination.

Response of liver antioxidant defense system to acute and chronic physical and psychological stresses in male rats.

The aim of this study was to evaluate the effect of acute and chronic physical and psychological stressors on the induction of oxidative stress in male rat liver. Male Wistar rats were randomly divided into 3 groups as following: control, physical and psychological stress groups. Stress was induced by communication box for one (acute), fifteen and thirty (chronic) days. Once stressor periods ended, rats were anesthetized and their liver dissected out for later assessments. Exposure to physical stress enhanced liver superoxide dismutase (SOD) (19.44 %) and glutathione S-transferase (GST) (21.84 %) activities and decreased glutathione (GSH) (30.03 %) level on the 1(st) day (p<0.05). SOD (24.13 and 18.43 %) and GST (27.77 and 21.27 %) activities were significantly increased, while catalase activity (29.74 and 24.41 %) and GSH level (35.05 and 31.05 %) were decreased in psychological stress group after 1 and 15 days (p<0.01 and p<0.05) compared to the 1(st) day value in control group, respectively. Psychological stress induced an increase in liver malondialdehyde (MDA) (46 %) and plasma corticosterone (36 %) levels on the 1(st) day (p<0.05). However, all parameters returned to their basal value after 30 days of stress. The results suggest that exposure to acute physical and psychological stressors induce the production of reactive oxygen species and oxidative stress in rat liver due to GSH depletion and the decreased catalase activity. The elevation of lipid peroxidation and corticosterone level in acute psychological stress may lead to more profound oxidative damage than acute physical stress. Moreover, cell protection in hepatic tissue of chronically stressed rats is indicative of possible late adaptation of the animals to stress.

Identification of morphine accumulation in the rat embryo central nervous system: a c14-morphine administration study.

BACKGROUND: Previous studies have shown that morphine consumption during pregnancy may cause delay or defect of embryo development or abnormal nervous system function in the human and animal models. In the present study, the highest density of morphine accumulation in the central nervous system of rat embryos was evaluated using C14-morphine. METHODS: Female Wistar rats (W 170-200 g) used and were crossed with male rats and coupling time was recorded (Embryonic day 0-E0). Experimental groups received 0.05 mg/ml of C14-morphine in drinking water daily. On the 10(th) and 17(th) days of pregnancy, pregnant rats were anesthetized and the embryos with these uterus and placenta were surgically removed and were fixed in formalin 10% for 4 week. Then the embryos were processed, sectioned in 25 µm and 5 µm thicknesses, fixed on the glasses for further evaluations. The sectioned in 25, the glasses were fixed on the Blanc black and white film for 6 h. Then, the films were appeared and their negatives were prepared. The sectioned in five staining hematoxylin and eosin by light microscope and MOTIC software. RESULTS: Our results indicated that the highest C14-morphine accumulation was observed in the vesicles and the ventricular choroid plexus (CP) of (E17) embryos, whereas, in the (E10) embryos. Highest concentration was observed in the brain vesicles and the ventricular CP. In addition, this study showed the surface area of lateral, 3(rd) and 4(th) ventricular CP in the experimental groups were increased in compared to control groups. CONCLUSIONS: Our results indicated that effects of morphine on reduction of embryos brain development may be due to the highest accumulation of C14-morphine in the CP and brain vesicles.

Comparison of the effects of acute and chronic psychological stress on metabolic features in rats.

This study was aimed to compare the effects of acute and chronic psychological stress on metabolic factors. Forty-two male Wistar rats were divided into control and stressed groups. Stress was applied by a communication box acutely (1 d) and chronically (15 and 30 d). Blood sampling was carried out by retro-orbital-puncture method. The plasma levels of glucose, cholesterol, triglyceride, insulin, and corticosterone were measured. In addition, feed and water intake, latency to eat and drink, adrenal and body weights were determined. Acute and chronic psychological stress did not significantly change basal plasma corticosterone levels. However, immediately (1 min) after acute exposure to stress, plasma corticosterone level increased compared to that before stress exposure. Acute stress increased plasma insulin levels significantly. Fifteen days of stress exposure resulted in plasma glucose increase. Chronic stress significantly increased feed intake, latency to eat, and adrenal weight compared to acute stress. The body weights of both control and stressed groups increased markedly during the experiment. Homeostasis model assessment of insulin resistance (HOMA-IR) index did not change significantly in the stressed group. In conclusion, application of acute and chronic psychological stress leads to different metabolic and/or behavioral changes but the metabolic changes resulting from acute exposure to stress seem to be more pronounced.

Effects of acute and chronic psychological stress on isolated islets' insulin release.

This study investigated the effects of acute and chronic psychological stress on glucose-stimulated insulin secretion from isolated pancreatic islets. Male Wistar rats were divided into two control and stressed groups; each further was allocated into fed and fasted groups. Stress was induced by communication box for one (acute), fifteen and thirty (chronic) days. After islet isolation, their number, size and insulin output were assessed. Plasma corticosterone level was determined. In fasted animals, acute stress increased basal and post stress plasma corticosterone level, while 30 days stress decreased it compared to day 1. In fed rats, acute stress increased only post stress plasma corticosterone concentration, however, after 15 days stress, it was decreased compared to day 1. Acute stress did not change insulin output; however, the insulin output was higher in the fed acutely stressed rats at 8.3 and 16.7 mM glucose than fasted ones. Chronic stress increased insulin output on day 15 in the fasted animals but decreased it on day 30 in the fed animals at 8.3 and 16.7 mM glucose. In the fasted control rats insulin output was lower than fed ones. In the chronic stressed rats insulin output at 8.3 and 16.7 mM glucose was higher in the fasted than fed rats. The number of islets increased in the fasted rats following 15 days stress. This study indicated that the response of the isolated islets from acute and chronically stressed rats are different and depends on the feeding status.

High-fat diet did not change metabolic response to acute stress in rats.

This study investigated the effects of high-fat diet on metabolic factors in the presence of acute foot-shock and psychological stresses in male Wistar rats. The animals were divided into high-fat (45 % cow intra-abdominal fat) and normal (standard pellets) diet groups; then, each group was allocated into stressed and control groups. Stress was induced by a communication box. Blood samples were collected by retro-orbital-puncture method under isoflurane anesthesia. Plasma levels of glucose, insulin, triglyceride, cholesterol, free fatty acid and corticosterone were measured. Water and food intake significantly decreased in high-fat diet group; however, their weight did not change compared with the normal diet group. The level of fasting plasma glucose in the high-fat diet group decreased whereas, the fasting plasma insulin level did not significantly change. Stress increased the plasma glucose level 15 minutes after oral glucose tolerance test (OGTT) in both diet subgroups. The concentration of plasma insulin increased after stress induction in fasting and 15 minutes after performing OGTT. The increase in the plasma level of corticosterone was significant in both diet subgroups of only the foot-shock stress group. Plasma level of cholesterol and triglyceride in the high-fat diet group significantly increased; however, foot-shock stress decreased only triglyceride concentration. Plasma level of the fatty acids did not change in any of the groups. Statistical analysis showed no significant interaction between high-fat diet and stress. As a whole, the results showed that the high-fat diet used in the present study did not noticeably affect metabolic parameters even in the presence of acute stress.