Monosodium glutamate administration early in life alters pineal melatonin nocturnal profile in adulthood

The pineal gland synthesizes melatonin exclusively at night, which gives melatonin the characteristic of a temporal synchronizer of the physiological systems. Melatonin is a regulator of insulin activities centrally and also peripherally and its synthesis is reduced in diabetes. Since monosodium glutamate (MSG) is often used to induce the type 2 diabetic and metabolic syndrome in animal models, the purpose of this work is to evaluate the potential effects of MSG given to neonates on the pineal melatonin synthesis in different aged male and female rats. Wistar rats were subcutaneously injected with MSG (4mg/g/day) or saline solution (0.9%) from the second to eighth post-natal day. The circadian profiles both melatonin levels and AANAT activity were monitored at different ages. Body weight, naso-anal length, adipose tissues weight, GTT, ITT and serum insulin levels were also evaluated. Typical obesity with the neonatal MSG treatment was observed, indicated by a great increase in adipose depots without a concurrent increase in body weight. MSG treatment did not cause hyperglycemia or glucose intolerance, but induced insulin resistance. An increase of melatonin synthesis at ZT 15 with phase advance was observed in in some animals. The AANAT activity was positively parallel to the melatonin circadian profile. It seems that MSG causes hypothalamic obesity which may increase AANAT activity and melatonin production in pineal gland. These effects were not temporally correlated with insulin resistance and hyperinsulinemia indicating the hypothalamic lesions, particularly in arcuate nucleus induced by MSG in early age, as the principal cause of the increase in melatonin production.

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Concurrent Prebiotic Intake Reverses Insulin Resistance Induced by Early-Life Pulsed Antibiotic in Rats

Biomedicines ◽

10.3390/biomedicines9010066 ◽

2021 ◽

Vol 9 (1) ◽

pp. 66 ◽

Cited By ~ 1

Author(s):

Teja Klancic ◽

Isabelle Laforest-Lapointe ◽

Jolene Wong ◽

Ashley Choo ◽

Jodi E. Nettleton ◽

...

Keyword(s):

Insulin Resistance ◽

Body Weight ◽

Fat Mass ◽

Acute Infection ◽

Female Rats ◽

Hepatic Expression ◽

Rat Pups ◽

Male And Female Rats ◽

Insulin Receptor Substrates ◽

Junction Proteins

Pulsed antibiotic treatment (PAT) early in life increases risk of obesity. Prebiotics can reduce fat mass and improve metabolic health. We examined if co-administering prebiotic with PAT reduces obesity risk in rat pups weaned onto a high fat/sucrose diet. Pups were randomized to (1) control [CTR], (2) antibiotic [ABT] (azithromycin), (3) prebiotic [PRE] (10% oligofructose (OFS)), (4) antibiotic + prebiotic [ABT + PRE]. Pulses of antibiotics/prebiotics were administered at d19–21, d28–30 and d37–39. Male and female rats given antibiotics (ABT) had higher body weight than all other groups at 10 wk of age. The PAT phenotype was stronger in ABT males than females, where increased fat mass, hyperinsulinemia and insulin resistance were present and all reversible with prebiotics. Reduced hypothalamic and hepatic expression of insulin receptor substrates and ileal tight junction proteins was seen in males only, explaining their greater insulin resistance. In females, insulin resistance was improved with prebiotics and normalized to lean control. ABT reduced Lactobacillaceae and increased Bacteroidaceae in both sexes. Using a therapeutic dose of an antibiotic commonly used for acute infection in children, PAT increased body weight and impaired insulin production and insulin sensitivity. The effects were reversed with prebiotic co-administration in a sex-specific manner.

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Effect of High-fat Diet on Tracheal Responsiveness to Methacholine and Insulin Resistance Index in Ovalbumin-sensitized Male and Female Rats

Iranian Journal of Allergy Asthma and Immunology ◽

10.18502/ijaai.v18i1.630 ◽

2019 ◽

Author(s):

Hassan Ghobadi ◽

Mohammad Reza Alipour ◽

Rana Keyhanmanesh ◽

Mohammad Hossein Boskabady ◽

Mohammad Reza Aslani

Keyword(s):

Insulin Resistance ◽

High Fat Diet ◽

Close Association ◽

Serum Insulin ◽

Resistance Index ◽

Normal Diet ◽

Female Rats ◽

High Fat ◽

Male And Female ◽

Male And Female Rats

Epidemiological and clinical studies have demonstrated a close association between obesity and asthma. The current study investigated the effect of high-fat diet on tracheal responsiveness to methacholine and insulin resistance in ovalbumin (OVA) sensitized male and female rats. The rats were divided into eight groups (n=6 per group): female with the normal diet (F+ND), male with the normal diet (M+ND), female OVA-sensitized with the normal diet (F+SND), male OVA-sensitized with the normal diet (M+SND), female with high-fat diet (F+HFD), male with high-fat diet (M+HFD), female OVA-sensitized with high-fat diet (F+SHFD), and male OVA-sensitized with high-fat diet (M+SHFD). All rats were fed for 8 weeks with high-fat diet or standard pelts, and for another 4 weeks, they were sensitized with OVA or saline. At the end of the study, the tracheal responsiveness to methacholine, serum insulin, and blood glucose levels was measured. Also, insulin resistance indexes were determined. OVA-sensitization and diet-induced obesity caused the curve of methacholine concentration response to shifting to the left. In addition, results indicated that the EC50 (the effective concentration of methacholine generating 50% of peak response) in F+SHFD rats was statistically lower than M+SHFD group (p<0.05). Moreover, insulin resistance was higher in the F+SHFD than the M+SHFD group (p<0.001). These results suggest that insulin resistance and metabolic syndrome may be involved in the pathogenesis of obesity associated with OVA-sensitized rats condition, especially in female animals.

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The induction of obesity in rodents by means of monosodium glutamate

British Journal Of Nutrition ◽

10.1079/bjn19760005 ◽

1976 ◽

Vol 35 (1) ◽

pp. 25-39 ◽

Cited By ~ 93

Author(s):

J. Bunyan ◽

Elspeth A. Murrell ◽

P. P. Shah

Keyword(s):

Body Weight ◽

Lipid Content ◽

Monosodium Glutamate ◽

Female Rats ◽

Male Mice ◽

Fat Pad ◽

Newborn Mice ◽

Female Mice ◽

Gold Thioglucose ◽

Male And Female Rats

1. Monosodium glutamate (MSG) was administered by various methods to mice and rats of various ages and the incidence of obesity was later measured.2. Newborn mice were injected subcutaneously with 3 mg MSG/g body-weight at 1, 2, 3, 6, 7 and 8 d of age; 16% died before weaning. Of the survivors, 90% or more became markedly obese. Mean carcass lipid content was increased by about 120% in both sexes at 20–30 weeks of age. In male mice, MSG treatment increased body-weight and epididymal fat pad weight, and greatly decreased adrenaline-stimulated lipolysis in isolated fat cells. Body-weight of females was not increased significantly. Food intake was not increased in either sex from weeks 13 to 15. Blood glucose level was not generally increased by MSG but some of the male mice had abnormally high values.3. Obesity was not detected in the offspring of female mice that had received 100 g MSG/kg diet, either from 3 weeks before mating until weaning, or from the 14th day of pregnancy until weaning.4. Intraperitoneal injection of 10 mg MSG/g body-weight (in two doses) at weaning increased carcass lipid content in female mice by 34% by 23 weeks of age, but female rats were not affected.5. The addition of 20 g MSG/l to the drinking-water from weaning onwards did not increase carcass lipid content in female rats or mice.6. The addition of 20 g MSG/kg diet from weaning onwards did not alter body-weight or carcass lipid content in male and female rats by 14 weeks of age.7. The obesity induced in mice by MSG was not associated with hyperphagia, unlike genetic obesity and obesity induced by gold thioglucose (GTG).8. All types of mouse studied, obese and lean, had essentially the same linear relationship between carcass water content and carcass lipid content.9. Although MSG-obese mice could not readily be differentiated from normal mice by the increase in body-weight, which was only about 10% compared to 50–120% for genetic and GTG-induced obesity, the proposed schedule of injections in the newborn was almost 100% reliable in inducing a high extent of adiposity.

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Abstract P088: Obesity, Hypertension and Insulin Resistance in a Primary Pediatric Setting in Southern Italy

Circulation ◽

10.1161/circ.129.suppl_1.p088 ◽

2014 ◽

Vol 129 (suppl_1) ◽

Author(s):

Giampaolo De Filippo ◽

Domenico Rendina ◽

Domenico Viggiano ◽

Antonio Fasolino ◽

Paola Sabatini ◽

...

Keyword(s):

Insulin Resistance ◽

Metabolic Syndrome ◽

Body Weight ◽

Children And Adolescents ◽

Diagnostic Criteria ◽

Southern Italy ◽

Serum Insulin ◽

High Density Lipoproteins ◽

Obese Children ◽

Campania Region

Background: Obesity is the main risk factor for essential hypertension (EH) in childhood. The O.Si.Me. study (Obesity and Metabolic Syndrome in children and adolescents) evaluated the prevalence of metabolic syndrome (MetS) and its constitutive traits in a sample of obese children and adolescents living in Campania, southern Italy. Patients and methods: Four hundred and fifteen children and adolescents consecutively referred to the National Health Service participating Outpatient Clinics for minor health problems and found to have a Body Mass Index (BMI) Z-score > 2.0 were enrolled in the study. The entire sample was screened for MetS, which was defined as the presence of at least 2 of the following alterations in addition to obesity: fasting hyperglycemia, low levels of high-density lipoproteins cholesterol, hypertriglyceridemia, and EH. The present analysis evaluated the clinical characteristics of the O.Si.Me subgroup of EH participants (systolic and/or diastolic BP ≥ 95 th percentile for age, gender and height) as compared with normotensive participants. Results: The prevalence of EH in the O.Si.Me population was 23.6 % (98/415, 48M and 50F.) and two-thirds of the EH participants met the MetS diagnostic criteria. The EH participants featured serum insulin and HOMA-IR levels significantly higher compared with normotensive ones (11.6±0.6 vs. 9.5±0.4 μIU/ml, p = 0.014; 2.6±0.1 vs. 2.2±0.1, p = 0.028 for insulin and HOMA-IR, respectively). These differences were common to boys and girls and remained significant after correction for age, pubertal stage, body weight, length, BMI, gestational age at birth, duration of breastfeeding and anthropometric parental parameters. Accordingly, children and adolescents with EH had a a relative risk of being insulin resistant (defined as a HOMA-IR ≥2.5) significantly greater compared to those without. Moreover, they exhibited higher serum creatinine levels (53.8±7.1 vs. 35.4±6.8 μmol/l, p=0.025) accounting for gender and body weight. Conclusions: More than a quarter of obese children and adolescents meet the diagnostic criteria for EH in the Campania region in southern Italy. These obese boys and girls have an increased prevalence of insulin resistance and apparently an initial reduction in renal function compared with obese children and adolescents with normal BP.

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Effects of Dehydroepiandrosterone Acetate on Metabolism, Body Weight and Composition of Male and Female Rats

Journal of Nutrition ◽

10.1093/jn/116.10.1977 ◽

1986 ◽

Vol 116 (10) ◽

pp. 1977-1983 ◽

Cited By ~ 75

Author(s):

Anthony R. Tagliaferro ◽

James R. Davis ◽

Stephen Truchon ◽

Nancy Van Hamont

Keyword(s):

Body Weight ◽

Female Rats ◽

Male And Female ◽

Male And Female Rats

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Insulin sensitivity, leptin, adiponectin, resistin, and testosterone in adult male and female rats after maternal-neonatal separation and environmental stress

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00271.2017 ◽

2018 ◽

Vol 314 (1) ◽

pp. R12-R21 ◽

Cited By ~ 14

Author(s):

Hershel Raff ◽

Brian Hoeynck ◽

Mack Jablonski ◽

Cole Leonovicz ◽

Jonathan M. Phillips ◽

...

Keyword(s):

Insulin Resistance ◽

Adult Male ◽

Rat Model ◽

Female Rats ◽

Male Rats ◽

Male And Female ◽

Neonatal Hypoxia ◽

Male And Female Rats ◽

Plasma Leptin ◽

Neonatal Separation

Care of premature infants often requires parental and caregiver separation, particularly during hypoxic and hypothermic episodes. We have established a neonatal rat model of human prematurity involving maternal-neonatal separation and hypoxia with spontaneous hypothermia prevented by external heat. Adults previously exposed to these neonatal stressors show a sex difference in the insulin and glucose response to arginine stimulation suggesting a state of insulin resistance. The current study used this cohort of adult rats to evaluate insulin resistance [homeostatic model assessment of insulin resistance (HOMA-IR)], plasma adipokines (reflecting insulin resistance states), and testosterone. The major findings were that daily maternal-neonatal separation led to an increase in body weight and HOMA-IR in adult male and female rats and increased plasma leptin in adult male rats only; neither prior neonatal hypoxia (without or with body temperature control) nor neonatal hypothermia altered subsequent adult HOMA-IR or plasma adiponectin. Adult male-female differences in plasma leptin were lost with prior exposure to neonatal hypoxia or hypothermia; male-female differences in resistin were lost in the adults that were exposed to hypoxia and spontaneous hypothermia as neonates. Exposure of neonates to daily hypoxia without spontaneous hypothermia led to a decrease in plasma testosterone in adult male rats. We conclude that neonatal stressors result in subsequent adult sex-dependent increases in insulin resistance and adipokines and that our rat model of prematurity with hypoxia without hypothermia alters adult testosterone dynamics.

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Voluntary wheel running is effective on suppressing of obesity but not on blood pressure and insulin resistance in female rats fed with high fructose diet

Trakia Journal of Sciences ◽

10.15547/tjs.2021.01.004 ◽

2021 ◽

Vol 19 (1) ◽

pp. 21-28

Author(s):

P. Tayfur ◽

K. Gökçe Tezel ◽

Ö. Barutçu ◽

S. Yılmaz ◽

E. Ö. Özgür ◽

...

Keyword(s):

Physical Activity ◽

Insulin Resistance ◽

Blood Pressure ◽

Body Weight ◽

Weight Gain ◽

Wheel Running ◽

Female Rats ◽

Walking Distance ◽

Voluntary Activity ◽

Voluntary Physical Activity

A fructose-rich diet has been known to cause metabolic syndrome effects such as body weight gain, increased blood pressure, blood lipids and glucose levels. The role of voluntary physical activity in these alterations is not known clearly. The aim of this study was to investigate the possible improving effects of voluntary physical activity in rats that were feeding with a fructose-rich diet. Spraque-Dawley female rats were separated as control (C;n=7), voluntary physical activity (A;n=7), fructose (F;n=7) and fructose+activity (F+A;n=7) groups. A and FA groups were kept in cages with running wheels during six weeks. F and FA groups were fed with adding 20% fructose in drinking water. Body weight was measured weekly and Lee Index was used to determine obesity. At the end of the feeding period serum glucose, insulin and lipid levels were measured by enzymatic method and blood pressure was determined with the tail-cuff method. Daily voluntary walking distance in F+A and A groups were similar during six weeks. Fructose intake induced to increase systolic blood pressure (p=0.001), diastolic blood pressure (p=0.002), glucose (p=0.041), insulin (p=0.001), cholesterol (p=0.001), triglyceride (p=0.001) and liver weight (p=0.035). The voluntary activity was found effective on the decrease of weight gain (p=0.018) however we did not observe a significant effect on blood pressure (p=0.917) and insulin resistance (p=0.565) following the fructose-rich diet. We conclude that voluntary activity has preventive effect on obesity but may not to be effective on increased blood pressure and insulin resistance in female rats which were feeding fructose-rich diet during six weeks.

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Electron microscopic changes of lymph nodes during correction of sodium glutamate action by melatonin

Reports of Morphology ◽

10.31393/morphology-journal-2020-26(1)-09 ◽

2020 ◽

Vol 26 (1) ◽

pp. 59-64 ◽

Cited By ~ 1

Author(s):

T.V. Harapko

Keyword(s):

Lymph Nodes ◽

Monosodium Glutamate ◽

Reproductive Age ◽

Female Rats ◽

Mesenteric Lymph Nodes ◽

Electron Microscopic ◽

Male And Female ◽

White Rats ◽

Mesenteric Lymph ◽

Male And Female Rats

The effect of monosodium glutamate on lymphoid organs remains insufficiently studied. Also, no less relevant is the issue of correction of changes caused by the action of monosodium glutamate. The aim of the study was to study the electron microscopic changes in the parenchyma of the lymph nodes of rats under the action of monosodium glutamate for six weeks and during correction with melatonin. The experimental study was performed on 66 white male and female rats of reproductive age. The structure of mesenteric lymph nodes of white rats under the conditions of physiological norm at the electron microscopic level was studied in 10 intact animals. Experimental animals were divided into 4 groups, each with 10 animals. The control was 16 white rats, which instead of a high-calorie diet (HCD) received a standard diet of vivarium. HCD was achieved by adding to the diet of monosodium glutamate at a dose of 0.07 g/kg body weight of rats. The dose of melatonin was 10 mg/kg body weight of rats, administered orally daily at the same time in the afternoon. The electron microscopic structure of the mesenteric lymph nodes of male and female rats of reproductive age of the intact and control groups corresponds to the species norm. The study showed that monosodium glutamate causes changes in the parenchyma of the lymph nodes as in alimentary obesity. After six weeks of HCD, the number of apoptically altered lymphocytes increases. That part of lymphocytes, which has no signs of karyorrhexis or karyolysis, has a karyolemma with deep intussusception, the cytoplasm is enlightened, the tubules of the granular endoplasmic reticulum in cells with signs of edema, dilated, mitochondrial ridges swollen, damaged. There are profound destructive changes in the cellular composition of the organ and violations at the level of all parts of the vascular bed. After six weeks of melatonin correction, the number of macrophages and plasma cells decreased, in some lymphocytes the nucleolus is not clearly expressed, the karyolemma is uneven, the cytoplasm is enlightened, the number of osmophilic (fatty) inclusions decreases both in the intercellular space and in the cytoplasm of the cell. Therefore, the introduction of melatonin led to a significant restoration of the structural organization, and hence the function of this organ.

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Toxicity Evaluation of a Traditional Polyherbal Unani Formulation Jawarish Shahi in Rats

The Journal of Phytopharmacology ◽

10.31254/phyto.2018.7502 ◽

2018 ◽

Vol 7 (5) ◽

pp. 412-418

Author(s):

Mohd Urooj ◽

◽

Mohammad Ahmed Khan ◽

G. Thejaswini ◽

Munawwar Husain Kazmi ◽

...

Keyword(s):

Body Weight ◽

Feed Intake ◽

Clinical Signs ◽

Female Rats ◽

Control Group ◽

Sprague Dawley ◽

Male And Female ◽

Salix Caprea ◽

Male And Female Rats ◽

Dose Levels

Jawarish Shahi (JS) is a compound polyherbal Unani pharmacopoeial formulation indicated for Khafqan (Palpitation), Nafkh-e-Shikam (Flatulence) and Waswas (Insanity; false perception and hallucinations). Jawarish Shahi contains herbs like Halela (Terminalia chebula), Amla (Emblica officinalis), Kishneez (Coriandrum sativum), Elaichi Khurd, (Elettaria cardamomum), and Bed Mushk (Salix caprea). The present study was carried out as per OECD 408 guidance to evaluate 90 days repeated oral dose toxicity in male and female Sprague Dawley rats. The study was performed at dose levels 1028 and 2000 mg/kg bw. No adverse effects were reported with respect to body weight, feed intake, behavior and clinical signs indicative of systemic toxicity. The expected growth pattern was observed in body weight and feed intake as compared to control group at both dose levels in male and female rats. There were few significant alterations with respect to hematology, and clinical biochemistry, however the results were within normal range thus considered toxicologically insignificant. The microscopic examination of different organ/tissue showed that no histopathological changes were observed. The findings of the study showed that No Observed Adverse Effect Level (NOAEL) for JS is greater than 2000 mg/kg body weight

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