Greater Abdominal Fat Research Articles

Ultrasound as a method to evaluate the distribution of abdominal fat in obese prepubertal children and the relationship between abdominal fat and metabolic alterations.

ObjectiveTo evaluate, using ultrasound, the distribution of abdominal fat in obese prepubertal children, as well as its possible correlation with metabolic changes due to obesity.Materials and MethodsThis was a cross-sectional study of prepubescent children: 77 obese children (33 girls and 44 boys), with a mean age of 7.31 years; and 31 normal-weight children (17 girls and 14 boys), with a mean age of 7.32 years. In all of the children, abdominal wall thickness (AWT) and abdominal fat thickness (AFT) were measured by ultrasound. For the evaluation of the associated metabolic alterations, serum levels of glycemia, HDL cholesterol, triglycerides, and insulin were determined.ResultsThe obese children presented with greater abdominal fat, predominantly greater AWT, without a significant gender-related difference in AWT or AFT. The homeostasis model assessment of insulin resistance (HOMA-IR) showed a significant direct correlation with AWT and AFT.ConclusionIn obese prepubertal children, the AWT, as measured by ultrasound, was shown to be more closely related to the HOMA-IR than to the lipid metabolism or glycemia.

Body composition and plasma lipid and stress hormone levels during 3 weeks of feed restriction and refeeding in low birth weight female pigs.

Compensatory growth in response to feed restriction (FR) affects deposition rates of lean and adipose tissues. It is, however, unclear whether pigs with low birth weight differ from their counterparts with normal birth weight with regard to compensatory growth. Female littermate pigs with low (UW; 1.1 kg) and normal (NW; 1.5 kg) birth weight were fed to appetite (control, CON) or feed restricted (RES) at 60% of DMI of the CON group between 78 and 98 d of age and subsequently refed at the level of the CON group until 131 d of age. Subgroups of pigs were slaughtered at 75, 98, 104, and 131 d of age to compare BW and body composition. Blood samples were taken at 98 and 119 d of age to analyze plasma metabolites and hormones. At birth UW pigs were shorter and had lower BW until 131 d of age than NW pigs ( < 0.05). Feed intake per kilogram of BW was greater in UW than in NW pigs ( < 0.01). The UW and NW pigs differed in carcass composition as indicated by greater relative subcutaneous fat at 75 d ( < 0.1), greater shoulder back fat ( < 0.05) at 98 d, and lower carcass weight at 131 d with greater abdominal and subcutaneous neck back fat in UW compared with NW pigs ( < 0.05). During FR, BW gain of RES pigs was lower than in NW pigs. The RES pigs showed greater feed intake after termination of FR until 131 d than CON pigs ( < 0.01). At 98 d RES pigs were leaner than CON pigs ( < 0.05). After 6 d of refeeding (104 d) relative fat depot weights were still smaller ( < 0.03) in RES pigs than in CON pigs. After 5 wk of refeeding, RES pigs had lower abdominal fat weights and greater plasma cortisol levels than CON pigs ( < 0.05). Regarding the plasma metabolite and hormone response, at 98-d fasting levels of plasma NEFA and glycerol were greater in RES than in CON pigs ( < 0.05), and after the drop in their levels after morning feeding ( < 0.001), plasma NEFA and glycerol and also triacylglycerol increased until the next meal in RES vs. CON pigs ( < 0.01). Plasma cortisol was greater in RES pigs after 3-wk FR ( < 0.05), whereas only a trend for increased plasma adrenalin concentrations in RES pigs at the end of the FR period and after 5 wk of refeeding was found ( < 0.1). In conclusion, UW pigs at 75 d of age (20 to 23 kg BW) had greater subcutaneous fat, whereas at 131 d (61 to 68 kg BW) they showed greater abdominal fat than NW pigs, suggesting that subcutaneous fat is deposited earlier than abdominal fat. The FR caused similar changes in body composition, plasma lipids, and stress hormones in UW and NW pigs.

Correlation Between Visceral Adipose Tissue and Biochemical Rates Related to Obesity in Newborns

INTRODUCTION: Increased visceral adipose tissue is strongly correlated with lipid profile and insulin resistance in adults and children. However, this correlation has not been assessed in newborns. The objective of this study was to verify the correlation between visceral adipose tissue and lipid profile, glucose, insulin, and homeostasis of resistance in newborns. METHODS: One hundred sixteen health newborns were recruited from Campina Grande, Brazil. Visceral fat was evaluated by ultrasonography. Cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, glucose, and insulin were measured from venous blood. homeostasis of resistance was also calculated. Pearson's correlation coefficient was performed to determine the relationship between visceral adipose tissue and lipid profile, glucose, insulin, and homeostasis of resistance. RESULTS: There was a significant association between visceral adipose tissue and insulin (r=0.30, P=.03) and homeostasis of resistance (r=1.61, P=.01). After multiple linear regression, only homeostasis of resistance remained associated with greater abdominal fat (r=1.61, P=.01). CONCLUSIONS: These findings suggest that increased visceral adipose tissue may be associated with insulin resistance in newborns. This positive correlation in neonatal period may contribute to early metabolic consequences in these children.

Associations of growth hormone secretagogue receptor (GHSR) genes polymorphisms and protein structure changes with carcass traits in sheep

Growth hormone secretagogue receptor (GHSR), a G protein-coupled receptor that binds ghrelin, plays an important role in the central regulation of pituitary growth hormone secretion, food intake, and energy homeostasis. Ghrelin receptor (GHSR) modulates many physiological effects and therefore is a candidate gene for sheep production performance. Polymorphism of the GHSR gene was detected by PCR–SSCP and DNA sequencing methods in 463 individuals. Two different structures in protein and nine single nucleotide polymorphisms (SNPs) were identified. The evaluation of the associations between these SSCP patterns with carcass traits suggests a positive effect of genotype TT and B structure on carcass weight, and body length (P<0.05). In addition, the animal with TC had greater abdominal fat than those with TT and CC (P<0.05) while CC genotype contributed to low blood cholesterol (P=0.04). The results confirm the hints suggesting that GHSR is a preferential target for further investigation on mutations that influence carcass trait variations.

Diets with reduced levels of nutrients supplemented with phytase and amino acids for broilers

One performance experiment and another metabolism experiment were conducted simultaneously with broilers from 22 to 35 days of age, evaluating five diets in six replicates. The control diet, without phytase, contained 19% of crude protein (CP); 0.412% of available phosphorus (aP) and 0.824% of calcium (Ca). The other diets were supplemented with phytase and were formulated with 0.262% of aP and 0.524% of Ca, with the CP level ranging from 19 to 16%. In the performance assay, 750 birds were used, in which were evaluated the performance, the tibia ash content and yields of carcass, cuts, and abdominal fat at 35 days of age. The metabolism assay was conducted with 90 birds, evaluating the apparent metabolizable energy corrected by the nitrogen balance; the metabolizability coefficient of dry matter (MCDM) of the diets, and also the balance and retention of nitrogen (N) and phosphorus (P). Diets did not affect performance, tibia ash content and yields of carcass, breast and thigh + drumstick. However, birds fed diet containing 16% of CP showed greater abdominal fat. Diets containing 19% of CP had the smaller energetic value and MCDM. The retention of N and P was higher in birds fed diets formulated with reduced CP content and phytase. Therefore, when the broiler feed is supplemented with phytase and amino acids it is possible to reduce the CP, aP and Ca for up to 16; 0.262 and 0.524%, respectively.

Effects of Body Composition and Adipose Tissue Distribution on Respiratory Function in Elderly Men and Women: The Health, Aging, and Body Composition Study

Previous cross-sectional studies demonstrate positive associations of fat-free mass and negative associations of centrally distributed fat deposits with respiratory function in older adults. Few studies have evaluated whether greater losses of muscle and increases in fat are associated with more rapid decline in respiratory function in aging. Nine hundred and fifty-seven men and 1,024 women aged, respectively, 73.6 ± 2.8 years and 73.2 ± 2.8 years at baseline were followed for 5 years. Body weight, waist circumference, bone mineral density, fat-free mass, fat mass and fat mass percentage as measured by DXA, abdominal subcutaneous and visceral adipose tissue, thigh muscle area, thigh intermuscular fat by CT and forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) were evaluated at baseline and after 5-years follow-up. Cross-sectional analyses showed that height and thigh muscle area were positively and visceral adipose tissue negatively related to FEV1 and FVC. Increase in fat mass over five years was associated with concurrent FEV1 and FVC decline. In analyses stratified by weight-change categories, men and women who gained weight (vs stable/lost weight) had more rapid declines in FEV1 and FVC. In this well-functioning cohort, less muscle and greater abdominal fat were each associated with poorer lung spirometry cross-sectionally, whereas increase in fat mass over 5 years was associated with concurrent FEV1 and FVC decline. Weight gain and accompanying fat deposition may accelerate age-related declines in respiratory function.

Neonatal and fetal exposure to trans-fatty acids retards early growth and adiposity while adversely affecting glucose in mice

Industrially produced trans-fatty acids (TFAs) consumed in Western diets are incorporated into maternal and fetal tissues and are passed linearly to offspring via breast milk. We hypothesized that TFA exposure in utero and during lactation in infants would promote obesity and poor glycemic control as compared with unmodified fatty acids. We further hypothesized that in utero exposure alone may program for these outcomes in adulthood. To test this hypothesis, we fed female C57/BL6 mice identical Western diets that differed only in cis- or trans-isomers of C18:1 and then aimed to determine whether maternal transfer of TFAs through pregnancy and lactation alters growth, body composition, and glucose metabolism. Mice were unexposed, exposed during pregnancy, during lactation, or throughout pregnancy and lactation to TFA. Body weight and composition (by computed tomography) and glucose metabolism were assessed at weaning and adulthood. Trans-fatty acid exposure through breast milk caused significant early growth retardation (P < .001) and higher fasting glucose (P = .01), but insulin sensitivity was not different. Elevated plasma insulin-like growth factor-1 in mice consuming TFA-enriched milk (P = .02) may contribute to later catch-up growth and leanness and preserved peripheral insulin sensitivity observed in these mice. Mice exposed to TFA in utero underwent rapid early neonatal growth with TFA-free breast milk and had significantly impaired insulin sensitivity (P < .05) and greater abdominal fat (P = .01). We conclude that very early catch-up growth resulted in impaired peripheral insulin sensitivity in this model of diet-related fetal and neonatal programming. Trans-fatty acid surprisingly retarded growth and adiposity while still adversely affecting glucose metabolism.

Is metabolic syndrome the link between obesity and postmenopausal breast cancer?.

Abstract Abstract #5040 Background&amp;#x2028; Obesity is associated with an increased incidence of postmenopausal breast cancer and a poorer prognosis. The mechanism by which body weight affects breast cancer outcome is complex and incompletely understood. While there is convincing evidence that an obesity induced increase in estrogen production contributes to this risk, recent literature also recognizes other factors such as hyperinsulinaemia, increased IGF-1, high triglycerides and greater abdominal fat accumulation. The clustering of these risk factors is the cornerstone of metabolic syndrome (MetS) diagnosis. Although studies on MetS and cancer are scarce, the components of MetS have individually being linked to the development of cancer and combined these metabolic abnormalities may have an additive effect leading to a more aggressive tumor phenotype.&amp;#x2028; Objective&amp;#x2028; The primary aim of this study was to describe for the first time the incidence of MetS and central obesity in women with postmenopausal breast cancer and examine the relationship between its presence and tumor size, pathological stage and axillary nodal involvement in an Irish population.&amp;#x2028; Design &amp; Setting&amp;#x2028; This was a prospective study of patients that presented to a specialist Breast Cancer Unit, in St James's Hospital, Dublin, with postmenopausal breast cancer between March 2007 and May 2008. Individuals underwent a metabolic and nutritional assessment. Studies performed included anthropometry, segmental body composition analysis by bioelectrical impedance, and quantification of fasting lipids, glucose, insulin, C-reactive protein and Serum Amyloid A.&amp;#x2028; Results&amp;#x2028; Seventy-nine female post-menopausal breast cancer patients were recruited. The median age was 68 years (Range 41-84). The mean Body Mass Index was 28.1 ± 5.1 kg/m2, with 70% patients overweight or obese and a further 84% centrally obese. There was no difference in method of detection, diagnosis or treatment between obese and non-obese patients. Over a third of patients (36%) had MetS, which exceeds the population norms reported at 21%. MetS was significantly associated with an adverse metabolic profile as well as increased total fat, trunk fat, an 8cm greater waistline, insulin resistance and hypertension. Moreover the presence of metabolic syndrome was significantly associated with larger tumors (P=0.006), a later stage of disease (P=0.010), lymphovascular invasion (p=0.006) and axillary node involvement (P=0.014) compared to patients without MetS.&amp;#x2028; Conclusion We report for the first time, a high prevalence of MetS and central obesity in a cohort of Irish postmenopausal breast cancer patients. The presence of the MetS seems to be associated with a more aggressive tumor phenotype. The prevalence of these altered metabolic profiles may be a key factor in determining the metastatic potential and prognosis of postmenopausal breast cancer. Therapeutic strategies that correct these abnormalities represent an exciting avenue for future prevention and treatment of breast cancer. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 5040.

Laparoscopic Donor Nephrectomy: Effect of Perirenal Fat upon Donor Operative Time

Previous attempts to correlate preoperative patient characteristics with operative complexity and operative time prior to laparoscopic donor nephrectomy have found few consistent relationships. The purpose of this study is to determine the effect of abdominal and perirenal fat measured with preoperative computerized tomography (CT) upon subsequent operative time and complexity during hand-assisted laparoscopic donor nephrectomy. A retrospective chart, database, and CT angiogram review was conducted on 103 consecutive patients who underwent a hand-assisted laparoscopic donor nephrectomy. Perirenal fat and abdominal wall fat were correlated with a variety of parameters including operative time. Univariate and multivariate regression analysis was performed and p values<0.05 were considered significant. There was no correlation between operative time and body mass index (BMI), abdominal fat measurements, or spleno-renal distance. There was a significant positive correlation between operative time and anterior perirenal fat (r=0.28, p=0.005), posterior perirenal fat (r=0.20, p=0.05), and donor CPK levels (r=0.53, p<0.001). Men had greater perirenal fat, while women had greater abdominal fat. A multivariate model including anterior perirenal fat measurement accounted for 20% of the variance in operative time. This is the first study to demonstrate that increased perirenal fat increases operative complexity as measured by operative time. This information may potentially be used to help predict operative complexity based upon measurable preoperative variables and help improve operating room efficiency and donor and recipient outcomes.