The Vagus Nerve and Spleen: Influence on White Adipose Mass and Histology of Obese and Non-obese Rats

The vagus nerve (VN) and spleen represent a complex interface between neural and immunological functions, affecting both energy metabolism and white adipose tissue (WAT) content. Here, we evaluated whether vagal and splenic axis participates in WAT mass regulation in obese and non-obese male Wistar rats. High doses of monosodium glutamate (M; 4 g/Kg) were administered during the neonatal period to induce hypothalamic lesion and obesity (M-Obese rats). Non-obese or Control (CTL) rats received equimolar saline. At 60 days of life, M-Obese and CTL rats were randomly distributed into experimental subgroups according to the following surgical procedures: sham, subdiaphragmatic vagotomy (SV), splenectomy (SPL), and SV + SPL (n = 11 rats/group). At 150 days of life and after 12 h of fasting, rats were euthanized, blood was collected, and the plasma levels of glucose, triglycerides, cholesterol, insulin, and interleukin 10 (IL10) were analyzed. The visceral and subcutaneous WAT depots were excised, weighed, and histologically evaluated for number and size of adipocytes as well as IL10 protein expression. M-Obese rats showed higher adiposity, hyperinsulinemia, hypertriglyceridemia, and insulin resistance when compared with CTL groups (p < 0.05). In CTL and M-Obese rats, SV reduced body weight gain and triglycerides levels, diminishing adipocyte size without changes in IL10 expression in WAT (p< 0.05). The SV procedure resulted in high IL10 plasma levels in CTL rats, but not in the M-Obese group. The splenectomy prevented the SV anti-adiposity effects, as well as blocked the elevation of IL10 levels in plasma of CTL rats. In contrast, neither SV nor SPL surgeries modified the plasma levels of IL10 and IL10 protein expression in WAT from M-Obese rats. In conclusion, vagotomy promotes body weight and adiposity reduction, elevating IL10 plasma levels in non-obese animals, in a spleen-dependent manner. Under hypothalamic obesity conditions, VN ablation also reduces body weight gain and adiposity, improving insulin sensitivity without changes in IL10 protein expression in WAT or IL10 plasma levels, in a spleen-independent manner. Our findings indicate that the vagal-spleen axis influence the WAT mass in a health state, while this mechanism seems to be disturbed in hypothalamic obese animals.

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De Novo expression of uncoupling proteins-3 in liver is associated to a reduction of body weight gain and adiposity after fenofibrate treatment of diet-induced obese rats

Atherosclerosis Supplements ◽

10.1016/s1567-5688(02)80434-2 ◽

2002 ◽

Vol 3 (2) ◽

pp. 159

Keyword(s):

Body Weight ◽

Weight Gain ◽

De Novo ◽

Body Weight Gain ◽

Uncoupling Proteins ◽

Fenofibrate Treatment ◽

Obese Rats

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Losartan prevents body weight gain in diet induced obese rats

The FASEB Journal ◽

10.1096/fasebj.26.1_supplement.877.10 ◽

2012 ◽

Vol 26 (S1) ◽

Author(s):

Pauline M Smith ◽

Charles C.T. Hindmarch ◽

David Murphy ◽

Alastair V. Ferguson

Keyword(s):

Body Weight ◽

Weight Gain ◽

Body Weight Gain ◽

Obese Rats

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Encapsulated Mulberry Fruit Extract Alleviates Changes in an Animal Model of Menopause with Metabolic Syndrome

Oxidative Medicine and Cellular Longevity ◽

10.1155/2019/5360560 ◽

2019 ◽

Vol 2019 ◽

pp. 1-23 ◽

Cited By ~ 2

Author(s):

Jintanaporn Wattanathorn ◽

Supannika Kawvised ◽

Wipawee Thukham-mee

Keyword(s):

Oxidative Stress ◽

Metabolic Syndrome ◽

Body Weight ◽

Weight Gain ◽

Protein Expression ◽

Body Weight Gain ◽

Atherogenic Index ◽

Fruit Extract ◽

Mulberry Fruit ◽

Oxidative Stress Status

Currently, the therapeutic strategy against metabolic syndrome and its complications is required due to the increasing prevalence and its impact. Due to the benefits of both mulberry fruit extract and encapsulation technology, we hypothesized that encapsulated mulberry fruit extract (MME) could improve metabolic parameters and its complication risk in postmenopausal metabolic syndrome. To test this hypothesis, female Wistar rats were induced experimental menopause with metabolic syndrome by bilateral ovariectomy (OVX) and high-carbohydrate high-fat (HCHF) diet. Then, they were orally given MME at doses of 10, 50, and 250 mg/kg BW for 8 weeks and the parameters, such as percentage of body weight gain, total cholesterol, triglycerides, HDL-C, LDL-C, atherogenic index, fasting blood glucose, plasma glucose area under the curve, serum angiotensin-converting enzyme (ACE), oxidative stress status, histology, and protein expression of PPAR-γ, TNF-α, and NF-κB in adipose tissues were determined. MME improved body weight gain, adiposity index, glucose intolerance, lipid profiles, atherogenic index, ACE, oxidative stress status, and protein expression of TNF-αand NF-κB. Moreover, MME attenuated adipocyte hypertrophy and enhanced PPAR-γexpression. Taken altogether, MME decreased metabolic syndrome and its complication via the increased PPAR-γexpression. Therefore, MME is the potential candidate for improving metabolic syndrome and its related complications. However, further research in clinical trial is still necessary.

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Chronic vitamin A-enriched diet feeding induces body weight gain and adiposity in lean and glucose-intolerant obese rats of WNIN/GR-Ob strain

Experimental Physiology ◽

10.1113/ep085027 ◽

2015 ◽

Vol 100 (11) ◽

pp. 1352-1361 ◽

Cited By ~ 8

Author(s):

Shanmugam M. Jeyakumar ◽

Alex Sheril ◽

Ayyalasomayajula Vajreswari

Keyword(s):

Body Weight ◽

Weight Gain ◽

Vitamin A ◽

Body Weight Gain ◽

Obese Rats

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Dietary Whole Egg Reduces Body Weight Gain in a Dose-Dependent Manner in Zucker Diabetic Fatty Rats

Journal of Nutrition ◽

10.1093/jn/nxz143 ◽

2019 ◽

Vol 149 (10) ◽

pp. 1766-1775 ◽

Cited By ~ 2

Author(s):

Cassondra J Saande ◽

Joseph L Webb ◽

Paige E Curry ◽

Matthew J Rowling ◽

Kevin L Schalinske

Keyword(s):

Vitamin D ◽

Body Weight ◽

Weight Gain ◽

Body Weight Gain ◽

Dependent Manner ◽

Dietary Recommendations ◽

Zucker Diabetic Fatty Rats ◽

Zdf Rats ◽

Dose Dependent ◽

Whole Egg

ABSTRACT Background We previously reported that a whole-egg–based diet attenuated weight gain in rats with type 2 diabetes (T2D) and more effectively maintained vitamin D status than an equivalent amount of supplemental cholecalciferol. Objectives The objective of this study was to determine the lowest dose of whole egg effective at maintaining vitamin D homeostasis and attenuating the obese phenotype in T2D rats. Methods Zucker diabetic fatty (ZDF) rats (n = 40; age 6 wk; prediabetic) and their lean controls (n = 40; age 6 wk) were randomly assigned to a diet containing 20% casein (CAS) or 20%, 10%, 5%, or 2.5% protein from whole egg (20% EGG, 10% EGG, 5% EGG, and 2.5% EGG, respectively). All diets contained 20% total protein (wt:wt). All rats received their respective diets for 8 wk, at a stage of growth and development that translates to adolescence in humans, until 14 wk of age, a point at which ZDF rats exhibit overt T2D. Weight gain was measured 5 d/wk, and circulating 25-hydroxyvitamin D [25(OH)D] was measured by ELISA. Mean values were compared by 2-factor ANOVA. Results The 20% EGG diet maintained serum 25(OH)D at 30 nmol/L in ZDF rats, whereas the 10%, 5%, and 2.5% EGG diets did not prevent insufficiency, resulting in mean serum 25(OH)D concentrations of 24 nmol/L in ZDF rats. Body weight gain was reduced by 29% (P < 0.001) and 31% (P < 0.001) in ZDF rats consuming 20% and 10% EGG diets, respectively, and by 16% (P = 0.004) and 12% (P = 0.030) in ZDF rats consuming 5% and 2.5% EGG diets, respectively, compared with CAS. Conclusions Whole-egg–based diets exerted a dose-dependent response with respect to attenuating weight gain. These data could support dietary recommendations aimed at body weight management in individuals predisposed to obesity and T2D.

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Effect of phenoxybenzamine on development of adipose tissue in lean and obese Zucker rats

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1982.243.5.e398 ◽

1982 ◽

Vol 243 (5) ◽

pp. E398-E406

Author(s):

K. Comai ◽

A. C. Sullivan

Keyword(s):

Body Weight ◽

Weight Gain ◽

Cell Size ◽

Body Weight Gain ◽

Zucker Rats ◽

Fat Cell ◽

Fat Depots ◽

Fat Cell Size ◽

Obese Rats ◽

Fat Depot

Young male Zucker lean (Fa/-) and obese (fa/fa) rats were fed the alpha-adrenergic blocking agent phenoxybenzamine as a dietary admixture for 35 days. In lean and obese rats, phenoxybenzamine treatment decreased significantly body weight gain, food consumption, grams of carcass fat, and grams of carcass protein. Lean rats exhibited reduced fat cell size and number in retroperitoneal, epididymal, and inguinal fat depots. Obese rats treated with phenoxybenzamine exhibited significantly decreased numbers of fat cells in the retroperitoneal, epididymal, and inguinal fat depots and a small decreased cell size in the inguinal fat depot only. The levels of carcass fat and protein and fat cell number in obese and lean rats treated with phenoxybenzamine for 35 days were similar to pretreatment values in agreement with the lack of body weight gain. Although values in agreement with the lack of body weight gain. Although rats exhibited marked decreases in fat accumulation during phenoxybenzamine treatment, fat cell size and number returned to control values during the posttreatment period with a marked hyperplasia occurring particularly in the retroperitoneal fat depot of obese rats. Serum levels of insulin were suppressed and free fatty acid levels increased in obese rats during phenoxybenzamine treatment, suggesting a stimulation of the sympathoadrenal system. This study shows that despite severe restrictions in fat cell proliferation during the rapid-growth phase of the obese Zucker rat, the mechanisms for cellular proliferation and fat deposition remain intact.

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Pharmacological characterisation of a new oral GH secretagogue, NN703

Acta Endocrinologica ◽

10.1530/eje.0.1410180 ◽

1999 ◽

pp. 180-189 ◽

Cited By ~ 37

Author(s):

BS Hansen ◽

K Raun ◽

KK Nielsen ◽

PB Johansen ◽

TK Hansen ◽

...

Keyword(s):

Body Weight ◽

Weight Gain ◽

Inositol Phosphate ◽

Body Weight Gain ◽

The Body ◽

Pituitary Cells ◽

Dependent Manner ◽

Rat Pituitary ◽

Rat Pituitary Cells ◽

Orally Active

NN703 is a novel orally active GH secretagogue (GHS) derived from ipamorelin. NN703 stimulates GH release from rat pituitary cells in a dose-dependent manner with a potency and efficacy similar to that of GHRP-6. The effect is inhibited by known GHS antagonists, but not by a GH-releasing hormone antagonist. Binding of (35)S-MK677 to the human type 1A GHS receptor (GHS-R 1A) stably expressed on BHK cells was inhibited by GHRP-6 and MK677 as expected. NN703 was also able to inhibit the binding of (35)S-MK677. However, the observed K(i) value was lower than expected, as based on the observed potencies regarding GH release from rat pituitary cells. Similarly, the effect of NN703 on the GHS-R 1A-induced inositol phosphate turnover in these cells showed a lower potency, when compared with GHRP-6 and MK677, than that observed in rat pituitary cells. The effect of i.v. administration of NN703 on GH and cortisol release was studied in swine. The potency and efficacy of NN703 on GH release were determined to be 155+/-23 nmol/kg and 91+/-7 ng GH/ml plasma respectively. A 50% increase of cortisol, compared with basal levels, was observed for all the tested doses of NN703, but no dose-dependency was shown. The effect of NN703 on GH release after i. v. and oral dosing in beagle dogs was studied. NN703 dose-dependently increased the GH release after oral administration. At the highest dose (20 micromol/kg), a 35-fold increase in peak GH concentration was observed (49.5+/-17.8 ng/ml, mean+/-s.e.m.). After a single i.v. dose of 1 micromol/kg the peak GH plasma concentration was elevated to 38.5+/-19.6 ng/ml (mean+/-s.e.m.) approximately 30 min after dosing and returned to basal level after 360 min. The oral bioavailability was 30%. The plasma half-life of NN703 was 4.1+/-0.4 h. A long-term biological effect of NN703 was demonstrated in a rat study, where the body weight gain was measured during a 14-day once daily oral challenge with 100 micromol/kg. The body weight gain was significantly increased after 14 days as compared with a vehicle-treated group. In summary, we here describe an orally active and GH specific secretagogue, NN703. This compound acts through a similar mechanism as GHRP-6, but has a different receptor pharmacology. NN703 induced GH release in both swine and dogs after i.v. and/or p.o. administration, had a high degree of GH specificity in swine and significantly increased the body weight gain in rats.

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