Retroperitoneal Fat Depots Research Articles

Sex and age affect depot expression of Ca2+ channels in rat white fat adipocytes.

White adipose tissue (WAT) requires extracellular Ca2+ influx for lipolysis, differentiation, and expansion. This partly occurs via plasma membrane Ca2+ voltage-dependent channels (CaVs). However, WFA exists in different depots whose function varies with age, sex, and location. To explore whether their CaV expression profiles also differ we used RNAseq and qPCR on gonadal, mesenteric, retroperitoneal, and inguinal subcutaneous fat depots from rats of different ages and sex. CaV expression was found dependent on age, sex, and WFA location. In the gonadal depots of both sexes a significantly lower expression of CaV1.2 and CaV1.3 was seen for adults compared to pre-pubescent juveniles. A lower level of expression was also seen for CaV3.1 in adult male but not female gonadal WFA, the latter of whose expression remained unchanged with age. Relatively little expression of CaV3.2 and 3.2 was observed. In post-pubescent inguinal subcutaneous fat, where the third and fourth mammary glands are located, CaV3.1 was decreased in males but increased in females - thus suggesting that this channel is associated with mammogenesis; however, no difference in intracellular Ca2+ levels or adipocyte size were noted. For all adult depots, CaV3.1 expression was larger in females than males - a difference not seen in pre-pubescent rats. These observations are consistent with the changes of CaV3.1 expression seen in 3T3-L1 cell differentiation and the ability of selective CaV3.1 antagonists to inhibit adipogensis. Our results show that changes in CaV expression patterns occur in fat depots related to sexual dimorphism: reproductive tracts and mammogenesis.

The Effect of High-Intensity Interval Training on the Adiponectin and TNF-α Levels of Serum and Adipose Tissues in Rats Fed with a High-Fat Diet Plus Sucrose Solution

Background: Adipocytokines secreted by adipose tissue are suggested to play a significant role in developing obesity-related complications. On the other hand, regular high-intensity interval training (HIIT) has been shown to reduce the risk of metabolic complications in obese subjects. Objectives: The effect of HIIT was evaluated on serum and adipose tissues (inguinal and retroperitoneal) adiponectin and TNF-α levels in rats fed with a high-fat diet plus sucrose solution (HFDS). Methods: Thirty-two male Wistar rats were randomly divided into HFDS and standard diet (SD) groups. After 12 weeks, each group was divided into a sedentary group and a HIIT group. An HIIT program was performed three times/week for eight weeks. Inguinal and retroperitoneal adipose tissues and serum were collected to assay adiponectin and TNF-α levels. Also, serum glucose and insulin levels, insulin resistance index (HOMA-IR) were measured. Results: HFDS significantly increased weight gain, weight of inguinal (P = 0.001) and retroperitoneal fat depots (P < 0.001), and HOMA-IR (P < 0.001) but reduced serum TNF-α levels (P = 0.011). HIIT was able to decrease weight gain and fat mass (P < 0.05) but did not affect inguinal and retroperitoneal fat depots’ adipokines (adiponectin and TNF-α) levels and HOMA-IR (P > 0.05). Conclusions: HIIT program can have significant reducing effects on weight gain and fat weights, but it does not effect on circulating and fat depots' adiponectin and TNF-α levels in rats fed a HFDS.

The effect of high-intensity interval training on serum and adipose tissues vaspin levels in rats fed a high-fat high-sucrose diet.

Vaspin is an adipocytokine with insulin-sensitizing and anti-inflammatory traits. The purpose of this study was to evaluate the effect of high-intensity interval training (HIIT) on serum, visceral and subcutaneous adipose tissue vaspin levels in rats exposed to a diet high in fat and sugar (HFS). Thirty-two male Wistar rats were randomly divided into HFS and standard diet (SD) groups. After 12weeks, each group was divided into sedentary and HIIT groups. HIIT program was performed 3times/week for 8weeks. Retroperitoneal adipose tissue, inguinal adipose tissue and serum were collected to analyze vaspin levels. Also, serum glucose and insulin levels, insulin resistance index (HOMA-IR) and retroperitoneal and inguinal fat weights were measured. HFS significantly increased weight gain, weight of inguinal (p=0.001) and retroperitoneal fat depots (p<0.001), serum glucose levels (p<0.001) and HOMA-IR (p<0.001). The HIIT was able to decline weight gain and fat mass (p<0.05) but did not affect inguinal and retroperitoneal fat depots' vaspin levels. Eight weeks' HIIT significantly increased serum vaspin (p=0.002) and decreased insulin (p=0.001) levels only in rats fed with SD. Although the HIIT program can cause significantly reducing effects on weight gain and fat depots' weights, it does not effect on circulating and fat depots' vaspin levels in rats fed an HFS.

Leptin Induces Proadipogenic and Proinflammatory Signaling in Adipocytes.

Background: Leptin is an adipokine with well-known effects on the central nervous system including the induction of energy expenditure and satiety. Leptin also has major relevance when activating immune cells and modulating inflammatory response. In obesity, increases in white adipose tissue accumulation and leptin levels are accompanied by hypothalamic resistance to leptin. Even though the adipose tissue is a leptin-rich environment, the local actions of leptin regarding adipogenesis were not thoroughly investigated until now. Here we evaluate the contributions of leptins direct signaling in preadipocytes and adipose tissue-derived stromal cells (ASCs) for adipogenesis.Methods: Adipocytes were differentiated from the murine lineage of preadipocytes 3T3-L1 or ASCs from subcutaneous and visceral (retroperitoneal) fat depots from C57Bl/6J mice. Differentiating cells were treated with leptin in addition to or in replacement of insulin. The advance of adipogenesis was assessed by the expression and secretion of adipogenesis- and lipogenesis-related proteins by Western blot and immunoenzimatic assays, and the accumulation of lipid droplets by fluorescence microscopy.Results: Leptin treatment in 3T3-L1 preadipocytes or ASCs increased the production of the adipogenesis- and lipogenesis-related proteins PLIN1, CAV-1, PPARγ, SREBP1C, and/or adiponectin at earlier stages of differentiation. In 3T3-L1 preadipocytes, we found that leptin induced lipid droplets' formation in an mTOR-dependent manner. Also, leptin induced a proinflammatory cytokine profile in 3T3-L1 and ASCs, modulating the production of TNF-α, IL-10, and IL-6. Since insulin is considered an essential factor for preadipocyte differentiation, we asked whether leptin would support adipogenesis in the absence of insulin. Importantly, leptin induced the formation of lipid droplets and the expression of adipogenesis-related proteins independently of insulin during the differentiation of 3T3-L1 cells and ASCs.Conclusions: Our results demonstrate that leptin induces intracellular signaling in preadipocytes and adipocytes promoting adipogenesis and modulating the secretion of inflammatory mediators. Also, leptin restores adipogenesis in the absence of insulin. These findings contribute to the understanding of the local signaling of leptin in precursor and mature adipose cells. The proadipogenic role of leptin unraveled here may be of especial relevance during obesity, when its central signaling is defective.

Safety assessment of the ethanolic extract of Gongronema latifolium Benth. leaves: a 90-day oral toxicity study in Sprague Dawley rats

BackgroundThe leaves of Gongronema latifolium Benth. have long been recognized traditionally as a remedy for a variety of ailments in Africa. This study was conducted to evaluate the safety profile of the ethanolic extract of G. latifolium (GLES) leaves through a repeated dose 90-day oral toxicity study in male and female of Sprague Dawley rats.MethodsGLES was orally administered at doses of 250, 500 and 1000 mg/kg/day consecutively for 90 days.ResultsNo behavioral or physiological changes and mortality were observed. GLES did not have a marked impact on general hematological parameters and did not precipitate nephrotoxicity. However, compared to the control, serum triglycerides, total cholesterol and low-density lipoprotein levels were lower and white adipose tissue paired retroperitoneal fat depots were depleted in male rats treated with GLES3 by the end of the experiment. The liver was significantly enlarged in GLES-treated rats of both sexes. Negative gender-specific alterations were observed with the highest dose. Adverse risk was evident in the female rats mainly due to marked body weight gain and cerebrum weight reduction.ConclusionFurther research is needed to reach more specific conclusions about to the safety of ingesting high doses of GLES for long periods of time.

Central and peripheral effects of physical exercise without weight reduction in obese and lean mice.

To investigate the central (hypothalamic) and peripheral effects of exercise without body weight change in diet-induced obesity (DIO). Twelve-week-old male C57Bl/6 mice received a control (C) or a high-fat diet (H). Half of them had free access to running wheels for 5 days/week for 10 weeks (CE) and HE, respectively). Hypothalamic expression of genes related to energy homeostasis, and leptin (Stat3 and p-Stat3) and insulin (Akt and p-Akt) signaling were evaluated. Glucose and leptin tolerance, peripheral insulin sensitivity, and plasma insulin, leptin and adiponectin were determined. Perigonadal and retroperitoneal fat depots were increased by diet but reduced by exercise despite lack of effect of exercise on body weight. Blood glucose during intraperitoneal glucose tolerance test (ipGTT) was higher and glucose decay during intraperitoneal insulin tolerance test (ipITT) was lower in H and HE compared with C and CE. Exercise increased liver p-Akt expression and reduced fast glycemia. High-fat diet increased plasma insulin and leptin. Exercise had no effect on insulin but decreased leptin and increased adiponectin. Leptin inhibited food intake in all groups. Hypothalamic total and p-Stat3 and Akt were similar amongst the groups despite higher plasma levels of leptin and insulin in H and HE mice. High-fat diet modulated gene expression favoring a positive energy balance. Exercise only marginally changed the gene expression. Exercise induced positive changes (decreased fast glycemia and fat depots; increased liver insulin signaling and adiponectin concentration) without weight loss. Thus, despite reducing body weight could bring additional benefits, the effects of exercise must not be overlooked when weight reduction is not achieved.

222 - Lycopene Shows Anti-protein Carbonylation and Anti-inflammatory Properties in Liver of Rats Treated with a Hypercaloric Refined-Carbohydrate Rich Diet

Purpose High-sugar intake and obesity are strinctly related to oxidative and inflammatory damages which underlie developments of many severe clinical conditions. This study aimed to investigate the effects of a lycopene supplementation (Lyc-suppl) on protein carbonylation, lipid content and inflammatory marker in liver of obese rats treated with a hypercaloric refined-carbohydrate rich diet. Methods Animals were randomized in four groups: control (Co), control with Lyc-suppl (Co+Lyc), obese (Ob) and obese with Lyc-suppl (Ob+Lyc). Obese was induced by a hypercaloric refined-carbohydrate (75% energy) plus saturated fat based diet. Control diet consisted of a normocaloric oil-rich diet. Animals were treated during 30-wk. During the last 10wk animals were treated by intragastric gavage with lycopene (10mg/kg) or placebo. After 30-wk animals were sacrificed for obtaining liver and adipose tissues. Epididimal, retroperitoneal and visceral fat depots were weighted and used for the calculation of adiposity index (AI). Triglycerides (TG), tumor necrosis factor alpha (TNF-α) and protein carbonyl (PC) levels were assayed in liver tissues. Statistical analyses used ANOVA two-way and significance level of 5% (p Results All obese rats showed higher AI in comparison to Co rats and Lyc-suppl was not able to prevent obese development. PC levels in liver of Co was increased as well as in Ob (Co=Ob). Possible explanation for this unexpected finding was that Co diet was rich in vegetable oils which are prone to be oxidized and thus forming higher amounts of reactive carbonyl species. But, both Co+Lyc and Ob+Lyc groups showed lower PC levels in comparison to Co and Ob groups. In addition, liver tissues of Ob showed increased TG and TNF-α levels in comparison to Co and Co+Lyc. Liver tissues of Ob+Lyc showed lower levels of TG and TNF-α than Ob but still higher than Co or Co+Lyc levels. Conclusion Lyc-suppl shows anti-protein carbonylation in both high-oil and high-carbohydrate rich diets and induces lower lipid deposition and anti-inflammatory process in rat liver.

Ontogeny and Thermogenic Role for Sternal Fat in Female Sheep.

Brown adipose tissue acting through a unique uncoupling protein (UCP1) has a critical role in preventing hypothermia in newborn sheep but is then thought to rapidly disappear during postnatal life. The extent to which the anatomical location of fat influences postnatal development and thermogenic function in adulthood, particularly following feeding, is unknown, and we examined both in our study. Changes in gene expression of functionally important pathways (i.e., thermogenesis, development, adipogenesis, and metabolism) were compared between sternal and retroperitoneal fat depots together with a representative skeletal muscle over the first month of postnatal life, coincident with the loss of brown fat and the accumulation of white fat. In adult sheep, implanted temperature probes were used to characterize the thermogenic response of fat and muscle to feeding and the effects of reduced or increased adiposity. UCP1 was more abundant in sternal fat than in retroperitoneal fat and was retained only in the sternal depot of adults. Distinct differences in the abundance of gene pathway markers were apparent between tissues, with sternal fat exhibiting some similarities with muscle that were not apparent in the retroperitoneal depot. In adults, the postprandial rise in temperature was greater and more prolonged in sternal fat than in retroperitoneal fat and muscle, a difference that was maintained with altered adiposity. In conclusion, sternal adipose tissue retains UCP1 into adulthood, when it shows a greater thermogenic response to feeding than do muscle and retroperitoneal fat. Sternal fat may be more amenable to targeted interventions that promote thermogenesis in large mammals.

Highly palatable food access during adolescence increased anxiety-/depression-like behaviors in male, but not in female, rats

Objectives: This study was conducted to examine the sexual dimorphic effects of highly palatable food (HPF) access during adolescence on the neurochemistry and depression-/anxiety-like behaviors of rats.Methods: Male and female Sprague–Dawley pups had free access to chocolate cookie rich in fat (HPF) from postnatal day 28 in addition to ad libitum chow, and the control groups received only chow. The food conditions were continued throughout the entire experimental period, and the neurochemical and behavioral measurements were performed during young adulthood. Rats were subjected to the ambulatory activity, elevated plus maze, and forced swim tests. Corticosterone levels during 2 h of restraint stress were analyzed with radioimmunoassay, and ΔFosB and brain-derived neurotrophic factor (BDNF) expression in the nucleus accumbens (NAc) with Western blot analysis.Results: Cookie access did not affect body weight gain and total caloric intake in both sexes; however, it increased retroperitoneal fat depot only in males. The time spent in open arms during elevated plus maze test was decreased and immobility during forced swim test was increased in cookie-fed males, but not in cookie-fed females. Main effect of food condition on the stress-induced corticosterone increase was observed in males, but not in females, and cookie access increased BDNF expression in the NAc only in males.Conclusions: Increased BDNF expression in the NAc and fat depot, in addition to the stress axis dysfunction, may play roles in the pathophysiology of depression- and/or anxiety-like behaviors induced by cookie access.

Palatable food access during adolescence increased BDNF expression in the nucleus accumbens and anxiety-/depression-like behaviors in males, but not in females

ObjectivesThis study was conducted to examine sexual dimorphic effects of highly palatable food access during adolescence and youth on psychoemotional behaviors of rats and its underlying neural mechanism.MethodsMale and female Sprague Dawley pups had free access to chocolate cookie rich in fat (highly palatable food) from postnatal day 28 in addition to ad libitum chow, and the control groups received chow only. The food conditions were continued though out the entire experimental period, and the neurochemical and behavioral measurements were performed during young adulthood. Corticosterone levels during 2 h of restraint stress were analyzed with radioimmunoassay, and ΔFosB and brain-derived neurotrophic factor (BDNF) expression in the nucleus accumbens (NAc) with western blot analysis.ResultsCookie access did not affect body weight gain and total caloric intake in both sexes; however, it increased retroperitoneal fat depot only in males. The time spent in open arms during elevated plus maze test was decreased and immobility during forced swim test was increased in cookie-fed males, but not in cookie-fed females. Main effect of food condition on the stress-induced corticosterone increase was observed in males, but not in females, and cookie access increased BDNF expression in the NAc only in males.ConclusionsIncreased BDNF expression in the NAc and fat depot, in addition to the HPA axis dysfunction, may play roles in the pathophysiology of depression- and/or anxiety-like behaviors induced by cookie access.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Highly palatable food during adolescence and youth increased anxiety‐/depression‐like behaviors in males, but not in females

This study was conducted to examine sexual dimorphic effects of highly palatable food access during adolescence and youth on psycho‐emotional behaviors of rats and its underlying neural mechanism. Male and female Sprague‐Dawley pups had free access to chocolate cookie rich in fat (highly palatable food) from postnatal day 28 in addition to ad libitum chow, and the control groups received chow only. The food conditions were continued though out the entire experimental period, and the neurochemical and behavioral measurements were performed during young adulthood. Corticosterone levels during 2 h of restraint stress were analyzed with radioimmunoassay, and ΔFosB and brain‐derived neurotrophic factor (BDNF) expression in the nucleus accumbens (NAc) with Western blot analysis. Cookie access did not affect body weight gain and total caloric intake in both sexes; however, it increased retroperitoneal fat depot only in males. The time spent in open arms during elevated plus maze test was decreased and immobility during forced swim test was increased in cookie‐fed males, but not in cookie‐fed females. Main effect of food condition on the stress‐induced corticosterone increase was observed in males, but not in females, and cookie access increased BDNF expression in the NAc only in males. Increased BDNF expression in the NAc and fat depot, in addition to the stress axis dysfunction, may play roles in the pathophysiology of depression‐ and/or anxiety‐like behaviors induced by cookie access.Support or Funding InformationSupported by a grant from the Oromaxillofacial Dysfunction Research Center for the Elderly at Seoul National University in Korea (2015048003) funded by the Ministry of Science, ICT and future Planning

Effects of high-fat diet on somatic growth, metabolic parameters and function of peritoneal macrophages of young rats submitted to a maternal low-protein diet.

This study evaluated the effects of a post-weaning high-fat (HF) diet on somatic growth, food consumption, metabolic parameters, phagocytic rate and nitric oxide (NO) production of peritoneal macrophages in young rats submitted to a maternal low-protein (LP) diet. Male Wistar rats (aged 60 d) were divided in two groups (n 22/each) according to their maternal diet during gestation and lactation: control (C, dams fed 17 % casein) and LP (dams fed 8 % casein). At weaning, half of the groups were fed HF diet and two more groups were formed (HF and low protein-high fat (LP-HF)). Somatic growth, food and energy intake, fat depots, serum glucose, cholesterol and leptin concentrations were evaluated. Phagocytic rate and NO production were analysed in peritoneal macrophages under stimulation of zymosan and lipopolysaccharide (LPS)+interferon γ (IFN-γ), respectively. The maternal LP diet altered the somatic parameters of growth and development of pups. LP and LP-HF pups showed a higher body weight gain and food intake than C pups. HF and LP-HF pups showed increased retroperitoneal and epididymal fat depots, serum level of TAG and total cholesterol compared with C and LP pups. After LPS+IFN-γ stimulation, LP and LP-HF pups showed reduced NO production when compared with their pairs. Increased phagocytic activity and NO production were seen in LP but not LP-HF peritoneal macrophages. However, peritoneal macrophages of LP pups were hyporesponsive to LPS+IFN-γ induced NO release, even after a post-weaning HF diet. Our data demonstrated that there was an immunomodulation related to dietary fatty acids after the maternal LP diet-induced metabolic programming.

1149 Expression of genes involved in the initial steps of steroidogenesis in adipose tissue depots of dairy cows during the dry period and early lactation

In view of the significant changes in body fat content related to parturition and lactation in dairy cows, together with the role of adipose tissue (AT) not only as a store of steroid hormones but also as a potential site of steroidogenesis, mobilization of body reserves may also alter steroid hormone secretion and eventually reproduction. With this background, our research objectives were (1) to assess the expression of two rate-limiting factors of steroidogenesis, i.e., steroidogenic acute regulatory protein (StAR) and Cytochrome P450scc (CYP11A1) in bovine AT, (2) to characterize the time course of their mRNA abundance during late pregnancy and early lactation, and (3) to compare this time course in a subcutaneous versus a visceral fat depot. StAR triggers cholesterol delivery to the inner mitochondrial membrane (IMM) where CYP11A1 then initiates steroidogenesis by converting cholesterol to pregnenolone, the precursor of all other endogenous steroids. Biopsies were collected from 20 Holstein cows from the subcutaneous (sc) and the retroperitoneal fat depot (rp) on d −42 and d 1, 21, and 100 relative to calving. The mRNA abundance of StAR and CYP11A1 was assessed in the tissue samples by qPCR and normalized using the 4 most stable reference genes. Data were analyzed using the MIXED procedure of SAS. In scAT, the StAR mRNA abundance was lowest on d −42, increased on d 1 (P < 0.05) until d 21 to remain at this level at d 100 (∼3-fold greater than on d −42; P < 0.001). Expression of StAR mRNA in rpAT increased with time of lactation, but differences between sampling days were limited to d −42 versus d 100 (3.3-fold increase; P = 0.01). Expression of CYP11A1 mRNA was not detectable in both AT with the protocol used herein (suitability of the protocol was confirmed with ovary as positive control). The increased expression of StAR mRNA abundance after calving in rpAT and scAT indicate an increased capacity for cholesterol uptake to the IMM. Given the apparently absent expression of CYP11A1, de novo synthesis of steroid hormones in bovine AT seems implausible and AT steroid metabolism likely depends on the uptake of preformed steroid precursors. Cholesterol reaching the IMM may thus rather be metabolized to oxysterols which were suggested to have regulatory functions in adipocytes.

Characterization of TGF-β expression and signaling profile in the adipose tissue of rats fed with high-fat and energy-restricted diets

Transforming growth factor beta (TGF-β) plays an important role in the pathogenesis of obesity, influencing the release of inflammation mediators and promoting remodeling and collagen deposition in the adipose tissue (AT). In this context, this work aims to elucidate whether TGF-β and Smad-dependent or Smad-independent signaling pathways contribute to regional differentiation of AT in high-fat diet (HFD) and energy-restricted (ER) rat models. For this, TGF-β, TGF-β receptors I and II, PAI-1 and GLUT4 mRNA levels were quantified by real-time PCR, and western blotting assays allowed the semiquantification of TGF-β and proteins from Smad3, ERK1/2 and Akt signaling pathways in subcutaneous and visceral (epididymal, retroperitoneal and mesenteric) fat depots from control, HFD and ER-treated rats. HFD was associated to increased levels of TGF-β and PAI-1 mRNA in epididymal and retroperitoneal visceral fat depots, while ER diet induced a reduction of TGF-β mRNA levels in mesenteric, but surprisingly an increase in retroperitoneal fat. Regarding the different signaling pathways, contrarily to what was found for Smad3, activation of ERK1/2 and Akt in response to HFD was detected in all the visceral but not in subcutaneous fat depots. ER-treated rats presented a more heterogeneous signaling response, as well as decreased TGF-β receptors expression, in the different visceral fat depots. In conclusion, subcutaneous and visceral AT respond differently to distinct diet patterns regarding TGF-β expression and activated signaling pathways. Furthermore, the present study points that visceral AT should not be understood as a homogeneous entity since that response also varied in the different fat depots.

Body Fat Patterning, Hepatic Fat and Pancreatic Volume of Non-Obese Asian Indians with Type 2 Diabetes in North India: A Case-Control Study.

ObjectiveTo evaluate body fat patterning and phenotype including hepatic fat and pancreatic volume of non-obese (BMI: < 25 kg/m2) Asian Indians with type 2 diabetes residing in North India.MethodsNon-obese patients with type 2 diabetes (n = 93) and non-obese, normo-glycemic subjects (n = 40) were recruited. BMI, waist & hip circumferences, skinfold thickness at 8 sites, body fat, lean mass and detailed abdominal fat evaluation [total abdominal fat, total subcutaneous fat (superficial, deep, anterior, and posterior), total intra-abdominal fat (intra-peritoneal, retroperitoneal)], liver span, grades of fatty liver and pancreatic volume were compared.ResultsWaist circumference, subscapular skinfolds and total truncal fat (on DEXA) were higher whereas calf, total peripheral skinfolds and total leg fat (on DEXA) lower in patients. Specifically, the following volumes were higher in cases as compared to controls; total abdominal fat (19.4%), total intra-abdominal fat (49.7%), intra-peritoneal fat (47.7%), retroperitoneal fat (70.7%), pancreatic volume (26.6%), pancreatic volume index (21.3%) and liver span (10.8%). In cases, significant positive correlations were observed for pancreatic volume with BMI, waist and hip circumferences, W-HR, subscapular, abdominal and total truncal skinfolds, truncal, total subcutaneous, total intra-abdominal, intra-peritoneal, retroperitoneal fat depots, liver span and fatty liver.ConclusionsIn non-obese Asian Indians with type 2 diabetes, subcutaneous and intra-abdominal obesity, including fatty liver, and pancreatic volume were higher and peripheral subcutaneous adiposity was lower than BMI matched non-diabetic subjects. Importantly, increased pancreatic volume in patients was highly correlated with multiple measures of abdominal obesity and liver fat.

Endocrine and metabolic function in male Carioca High-conditioned Freezing rats

The aim of this study was to characterize Carioca High-conditioned Freezing rats (CHF) regarding their endocrine and metabolic backgrounds. We found an increase in serum corticosterone (CTRL: 96.7±21.65 vs CHF: 292.0±40.71ng/ml) and leptin (CTRL: 9.5±1.51 vs CHF: 19.2±4.32ng/ml). Serum testosterone (CTRL: 3.3±0.29 vs CHF: 2.0±0.28ng/ml) and T3 (CTRL: 52.4±2.74 vs CHF: 42.7±2.94ng/dl) were decreased in the CHF group, but serum TSH and T4 were unaffected. Body weight and food intake were unchanged, nevertheless retroperitoneal fat (CTRL: 2.2±0.24 vs CHF: 4.8±0.64g) and epididymal fat (CTRL: 2.6±0.20 vs CHF: 4.8±0.37g) depot weights were around 2-fold higher in CHF animals. BAT weight was similar in both groups. Serum triglycerides (CTRL: 41.4±6.03 vs CHF: 83.2±17.09mg/dl) and total cholesterol (CTRL: 181.6±5.61 vs CHF: 226.4±13.04mg/dl) were higher in the CHF group. Fasting glycemia (CTRL: 68.7±3.04 vs CHF: 82.3±2.99mg/dl) was also higher in the CHF group, however glucose tolerance test response and serum insulin levels were similar between the groups. Oxygen consumption (CTRL: 10.5±0.40 vs CHF: 7.9±0.58VO2ml/min/kg0.75) and BAT D2 activity (CTRL: 0.7±0.17 vs CHF: 0.3±0.04fmolT4/min/mg ptn) were lower in the CHF group. Our data show that anxiety could impair endocrine and metabolic functions and may contribute to the development of metabolic diseases.

Ginkgo biloba extract improves insulin signaling and attenuates inflammation in retroperitoneal adipose tissue depot of obese rats.

Due to the high incidence and severity of obesity and its related disorders, it is highly desirable to develop new strategies to treat or even to prevent its development. We have previously described that Ginkgo biloba extract (GbE) improved insulin resistance and reduced body weight gain of obese rats. In the present study we aimed to evaluate the effect of GbE on both inflammatory cascade and insulin signaling in retroperitoneal fat depot of diet-induced obese rats. Rats were fed with high fat diet for 2 months and thereafter treated for 14 days with 500 mg/kg of GbE. Rats were then euthanized and samples from retroperitoneal fat depot were used for western blotting, RT-PCR, and ELISA experiments. The GbE treatment promoted a significant reduction on both food/energy intake and body weight gain in comparison to the nontreated obese rats. In addition, a significant increase of both Adipo R1 and IL-10 gene expressions and IR and Akt phosphorylation was also observed, while NF-κB p65 phosphorylation and TNF-α levels were significantly reduced. Our data suggest that GbE might have potential as a therapy to treat obesity-related metabolic diseases, with special interest to treat obese subjects resistant to adhere to a nutritional education program.

Sex-related differences in the effects of high-fat diets on DHEA-treated rats.

Several studies have investigated the beneficial effects of dehydroepiandrosterone (DHEA) on lipid and glucose metabolism. However, many of these studies are inconclusive about the effects of DHEA administration on metabolic disorders, and there appear to be sex-related differences in the effects of DHEA treatment. Few animal studies have addressed the effects of DHEA on diet-induced metabolic disorders. The present study sought to ascertain whether sex differences exist in the effects of a high-fat diet (HFD) on weight gain, adiposity, and biochemical and hormonal parameters in DHEA-treated rats. Rats were fed a HFD for 4weeks and simultaneously received treatment with DHEA (10mg/kg by subcutaneous injection) once weekly. Body weight, retroperitoneal fat depot weight, serum glucose, insulin, and leptin levels, and hepatic lipids were measured. HFD exposure increased the adiposity index in both sexes, the hepatic triglyceride content in both sexes, and the hepatic total cholesterol level in males. Moreover, the HFD induced an increase in blood glucose levels in both sexes, and hyperinsulinemia in males. In this experimental model, DHEA treatment reduced hepatic triglyceride levels only in females, regardless of HFD exposure. Exposure to a HFD, even if it does not cause obesity, may enhance risk factors for metabolic disorders, and males are more sensitive to this effect. DHEA treatment can help prevent metabolic derangements, but its effect varies with sex.

Adiponectin links adipose tissue function and monocyte inflammatory responses during bovine metabolic stress

The periparturient period of dairy cows is characterized by intense lipid mobilization from adipose tissue leading to increased plasma concentrations of nonesterified fatty acids (NEFA). High NEFA are a predisposing factor for inflammatory based diseases. A major component of these diseases is uncontrolled macrophage/monocyte inflammatory responses. Changes in the endocrine activity of adipose tissue during the periparturient period could impact macrophage function by modifying the secretion of adipokines including adiponectin. Currently, the effects of adiponectin on monocyte activation in dairy cattle are unknown. In humans and rodents, this adipokine regulates monocyte phenotype and alterations in its plasma levels are linked with the development of inflammatory diseases. The objectives of this study were to establish associations between plasma adiponectin expression dynamics and different markers of lipid mobilization during the periparturient period of dairy cows and to characterize the effects of adiponectin on the inflammatory response of bovine monocytes. Plasma adiponectin, NEFA, BHB, albumin, and subcutaneous and retroperitoneal fat depots depth were measured during the periparturient period of dairy cows. In vitro, bovine monocytes were cultured with adiponectin to assess changes in pro-inflammatory responses following LPS stimulation. Results from this study demonstrate that alterations in plasma adiponectin levels in periparturient cattle are inversely correlated with the concentrations of plasma NEFA, an important marker of lipid mobilization. Furthermore, adiponectin exposure significantly decreased monocyte expression of TNFα after LPS stimulation thus markedly reducing their inflammatory response. Reduced plasma adiponectin during the periparturient period could predispose dairy cows to the development of uncontrolled monocyte inflammatory responses.

Vitamin D and calcium supplementation decrease body and fat weight gain and improve biomarkers of adiposity in diet‐induced obesity

Low vitamin D status (circulating concentration of 25(OH)D) and low calcium intake have been linked with an increased risk of obesity, however the underlying molecular mechanisms of vitamin D and calcium in obesity are not understood. To investigate effects of calcium and vitamin D supplementation on the development of obesity, male C57BL/6J mice (4 weeks of age) were fed for 10 weeks either a high fat (HF) diet (60% energy from fat) or HF diets containing 1.2% calcium, 10000 IU/kg vitamin D3 and their combination. The results obtained demonstrated that the calcium plus vitamin D3 supplementation reduced the body and adipose tissue (epididymal and retroperitoneal fat depots) weight gain and decreased the plasma glucose and insulin concentrations, as compared with the HF diet group. In addition, a high vitamin D3 intake significantly raised the plasma concentrations of 25(OH)D and its hormonal form, 1,25(OH)2D, in HF diet‐fed mice. These findings indicate that increased dietary vitamin D and calcium intakes improve biomarkers of adiposity, insulin sensitivity, and vitamin D status in diet‐induced obesity and suggest a role for vitamin D and calcium in preventing body and fat weight gain. Supported by USDA 2009–35200‐05008 and USDA SD00H325 to INS.