Body fat regulation after partial lipectomy in Siberian hamsters is photoperiod dependent and fat pad specific

Siberian hamsters exhibit seasonal fluctuations in body weight (fat). Initial exposure to a short photoperiod results in body fat loss that reverses after approximately 22 wk of short-day exposure. The purpose of this study was to determine whether Siberian hamsters are able to recover body fat after surgical reduction of total lipid stores and if so, whether this ability is photoperiod dependent and fat pad specific. Either the largest pair of internal fat pads, the epididymal white adipose tissue (EWAT) or one pair of two large external depots, the inguinal (IWAT) fat pads, were removed from male hamsters housed for 22 wk in a long (LD) or short (SD) photoperiod. Retroperitoneal fat pad (RWAT) mass was increased in LD EWAT- and IWAT-lipectomized hamsters. IWAT mass also was increased in the LD EWAT-lipectomized hamsters. Neither SD-lipectomized group compensated for body fat loss in any of the measured fat pads. Increased food intake was not necessary for total body fat recovery, but undereating partially may be responsible for the lack of recovery in SDs. The results of these experiments demonstrate a photoperiod-dependent ability of male Siberian hamsters to regulate total body fat after partial lipectomy. In addition, recovery involves a fat pad-specific compensatory response to partial lipectomy, rather than a general increase in lipid deposition in all fat depots.

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Regional differences in fat pad responses to short days in Siberian hamsters

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1989.257.6.r1533 ◽

1989 ◽

Vol 257 (6) ◽

pp. R1533-R1540 ◽

Cited By ~ 14

Author(s):

T. J. Bartness ◽

J. M. Hamilton ◽

G. N. Wade ◽

B. D. Goldman

Keyword(s):

Body Weight ◽

Body Fat ◽

Subcutaneous Fat ◽

Short Photoperiod ◽

Fat Pad ◽

Initial Exposure ◽

Short Day ◽

Siberian Hamsters ◽

Long Day ◽

Induced Changes

Siberian hamsters exhibit decreased body weight and fat after initial exposure to short photoperiods and increased body weight and fat after extended short photoperiod exposure. The purpose of the present experiments was to determine if uniform changes in white adipose tissue (WAT) pad weights and lipid metabolism correspond to these short photoperiod-induced changes in body fat. Carcass lipid content and testes and fat pad weights [retroperitoneal WAT (RWAT), epididymal WAT (EWAT), and inguinal and dorsal subcutaneous WAT, respectively] were decreased in male hamsters relative to their long day counterparts after 6 and 12 wk of short-day exposure. Moreover, EWAT and RWAT weight, EWAT specific lipoprotein lipase activity, and specific and total lipogenesis were disproportionately decreased relative to the subcutaneous fat pads. The changes in fat pad weight and metabolism were generally reversed coincident with the return to a long-day-like reproductive status after prolonged short-day exposure (24 and 30 wk). In a less detailed experiment, female Siberian hamsters had decreased body, fat pad, and uterine weights after 6 wk of short-day exposure; however, no fat pad-specific changes in weight were observed. The results of these experiments demonstrate that short-day-exposed male Siberian hamsters may be a useful model for examining mechanisms underlying fat pad-specific responses. In addition, gender appears to influence the pattern of short-day-induced lipid depletion in this species.

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White adipose tissue sensory nerve denervation mimics lipectomy-induced compensatory increases in adiposity

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00036.2005 ◽

2005 ◽

Vol 289 (2) ◽

pp. R514-R520 ◽

Cited By ~ 40

Author(s):

Haifei Shi ◽

Timothy J. Bartness

Keyword(s):

Adipose Tissue ◽

Body Fat ◽

White Adipose Tissue ◽

Sensory Nerve ◽

Sensory Innervation ◽

Siberian Hamsters ◽

Total Body Fat ◽

Total Body ◽

Lipid Stores ◽

The Brain

The sensory innervation of white adipose tissue (WAT) is indicated by the labeling of sensory bipolar neurons in the dorsal root ganglion after retrograde dye placement into WAT. In addition, immunoreactivity (ir) for sensory-associated neuropeptides such as calcitonin gene-related peptide (CGRP) and substance P in WAT pads also supports the notion of WAT sensory innervation. The function of this sensory innervation is unknown but could involve conveying the degree of adiposity to the brain. In tests of total body fat regulation, partial surgical lipectomy triggers compensatory increases in the mass of nonexcised WAT, ultimately resulting in restoration of total body fat levels in Siberian hamsters and other animals. The signal that triggers this compensation is unknown but could involve disruption of WAT sensory innervation that accompanies lipectomy. Therefore, a local and selective sensory denervation was accomplished by microinjecting the sensory nerve neurotoxin capsaicin bilaterally into epididymal WAT (EWAT) of Siberian hamsters, whereas controls received vehicle injections. Additional hamsters had bilateral EWAT lipectomy (EWATx) or sham lipectomy. As seen previously, EWATx resulted in significantly increased retroperitoneal WAT (RWAT) and inguinal WAT (IWAT) masses. Capsaicin treatment significantly decreased CGRP- but not tyrosine hydroxylase-ir, attesting to the diminished and selective sensory innervation. Capsaicin-treated hamsters also had increased RWAT and, to a lesser degree, IWAT mass largely mimicking the WAT mass increases seen after lipectomy. Collectively, these data suggest the possibility that information related to peripheral lipid stores may be conveyed to the brain via the sensory innervation of WAT.

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MEASURES OF BODY FAT AND HYDRATION IN ADOLESCENT BOYS

PEDIATRICS ◽

10.1542/peds.31.2.226 ◽

1963 ◽

Vol 31 (2) ◽

pp. 226-239

Author(s):

Felix P. Heald ◽

Edward E. Hunt ◽

Robert Schwartz ◽

Charles D. Cook ◽

Orville Elliot ◽

...

Keyword(s):

Body Fat ◽

Total Body Water ◽

Deuterium Oxide ◽

Subcutaneous Fat ◽

Body Water ◽

X Rays ◽

Adolescent Boys ◽

Fat Loss ◽

Total Body Fat ◽

Total Body

A study of total body fat by simultaneously performing a variety of measurements of adiposity on each of 66 adolescent boys is described. Estimates of total body fat by densitometry indicate a 50% loss of body fat's contribution to total body weight from 12 to 18 years. Total body water, as measured by deuterium oxide, increases from 61% at age 12 years to 65% at age 18 years. Fat loss from this measurement closely parallels the fat changes estimated from densitometry. Lean body mass, hydration and adiposity appear to reach adult values at the sixteenth year. Subcutaneous fat measured by soft tissue x-rays films of the arm shows a similar fat loss, and of the same magnitude, when compared to densitometry and total body water estimates of fat. The triceps skinfold has a high correlation in estimating losses in fat during adolescence. The skinfold technique at this site provided a practical and accurate estimate of adiposity in adolescent boys.

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Association between changes in fat distribution and biomarkers for breast cancer

Endocrine Related Cancer ◽

10.1530/erc-16-0490 ◽

2017 ◽

Vol 24 (6) ◽

pp. 297-305 ◽

Cited By ~ 11

Author(s):

Willemijn A van Gemert ◽

Evelyn M Monninkhof ◽

Anne M May ◽

Sjoerd G Elias ◽

Job van der Palen ◽

...

Keyword(s):

Breast Cancer ◽

Body Fat ◽

Multivariable Analysis ◽

Free Testosterone ◽

Abdominal Fat ◽

Sex Hormone Binding Globulin ◽

Study Cohort ◽

Fat Depots ◽

Total Body Fat ◽

Total Body

We assessed the associations between changes in total and abdominal fat and changes in biomarkers for breast cancer risk using data of the SHAPE-2 trial. In the SHAPE-2 trial, 243 postmenopausal overweight women were included. The intervention in this trial consisted of 5-6 kg weight loss either by diet only or exercise plus diet. After 16 weeks, we measured serum sex hormones, inflammatory markers, total body fat (measured by DEXA scan) and intra and subcutaneous abdominal fat (measured by MRI). Associations between changes in different body fat depots and biomarkers were analysed by linear regression using the study cohort irrespective of randomisation to make maximal use of the distribution of changes in fat measures. We found that a loss in total body fat was associated with favourable changes in free oestradiol, free testosterone, leptin and sex hormone binding globulin (SHBG). The loss of intra-abdominal fat was associated with a decrease in free testosterone, hsCRP and leptin, and an increase in SHBG. In the multivariable analysis, the best fitted models for the biomarkers free oestradiol, SHBG leptin and adiponectin included only total body fat. For free testosterone, this was subcutaneous abdominal fat, and for hsCRP and IL-6, only intra-abdominal fat change was important. For IL-6 and adiponectin, however, associations were weak and not significant. We conclude that, in our population of healthy overweight postmenopausal women, loss of fat at different body locations was associated with changes in different types of biomarkers, known to be related to risk of breast cancer.

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Effects of white adipose tissue grafts on total body fat and cellularity are dependent on graft type and location

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00116.2005 ◽

2005 ◽

Vol 289 (2) ◽

pp. R380-R388 ◽

Cited By ~ 15

Author(s):

Eva L. Lacy ◽

Timothy J. Bartness

Keyword(s):

Adipose Tissue ◽

Body Fat ◽

White Adipose Tissue ◽

Surgical Removal ◽

Siberian Hamsters ◽

Total Body Fat ◽

Donor Graft ◽

Total Body ◽

Tissue Grafts ◽

Autologous Grafts

Surgical removal of body fat (lipectomy) triggers compensatory increases in nonexcised white adipose tissue (WAT), thus restoring adiposity levels in many species, including Siberian hamsters. In Siberian hamsters, when their lipectomized WAT is transplanted to another site (autologous grafts, no net change in body fat), healthy grafts result, but the lipectomy-induced compensatory increases in nonexcised WAT masses are exaggerated, an effect that apparently occurs only when the grafts contact intact WAT. When WAT is added to nonlipectomized hamsters to increase body fat, native WAT pads do not decrease. Thus WAT addition or removal-replacement does not induce compensatory WAT responses consistent with total body fat regulation as does WAT subtraction. Therefore, we tested whether the exaggerated response to lipectomy occurring with autologous WAT transplantation is dependent on graft site placement and whether the donor graft source [inguinal or epididymal WAT (IWAT, EWAT), sibling vs. nonsibling] affected body fat responses to WAT additions in nonlipectomized hamsters. Lipectomized hamsters received subcutaneous autologous EWAT grafts placed remotely from other WAT (ventrum) or in contact with intact WAT (dorsum), whereas intact hamsters received EWAT or IWAT grafts from sibling or nonsibling donors. The exaggerated response to lipectomy only occurred when grafts were in contact with intact WAT. EWAT, but not IWAT, additions to nonlipectomized siblings or nonsiblings increased native IWAT and retroperitoneal WAT mass but not EWAT mass compared with controls. Collectively, WAT transplantation to either lipectomized or nonlipectomized hamsters increased body fat contingent on graft contact with intact or native WAT.

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Comparison of TOBEC-derived total body fat with fat pad weights

Physiology & Behavior ◽

10.1016/0031-9384(94)00216-r ◽

1995 ◽

Vol 57 (2) ◽

pp. 319-323 ◽

Cited By ~ 10

Author(s):

Janet Stenger ◽

Catherine Bielajew

Keyword(s):

Body Fat ◽

Fat Pad ◽

Total Body Fat ◽

Total Body

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The growth of Clun and Southdown sheep: body composition and the partitioning of total body fat

Animal Science ◽

10.1017/s000335610003213x ◽

1984 ◽

Vol 39 (3) ◽

pp. 405-411 ◽

Cited By ~ 23

Author(s):

B. W. Butler-Hogg

Keyword(s):

Body Composition ◽

Body Fat ◽

Relative Growth ◽

Fat Depots ◽

Breed Difference ◽

Total Body Fat ◽

Total Fat ◽

Total Body ◽

Omental Fat

ABSTRACTThe growth of Southdown and Clun lambs was studied over the period birth to 415 days of age.At birth, 50, 100, 150 and 200 days of age five lambs of each breed, and at 415 days three lambs of each breed, were slaughtered and their body composition determined by dissection.The relative growth of lean, bone and total body fat was not influenced by breed. At each age both Cluns and Southdowns had similar proportions of total body fat, and were considered to be at the same stage of maturity.There was a breed difference in fat partitioning, with the Clun depositing proportionately more of its total body fat intra-abdominally, compared with the Southdown. However, there was no significant effect of breed on the growth of individual fat depots relative to total fat. From earliest to latest the order of maturity was pericardial, intermuscular, perirenal-retroperitoneal, mesenteric, subcutaneous and lastly, omental fat.

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Effects of breed, sex and diet and their interactions on fat deposition and partitioning among depots of broiler chickens

Archives Animal Breeding ◽

10.5194/aab-49-181-2006 ◽

2006 ◽

Vol 49 (2) ◽

pp. 181-193 ◽

Cited By ~ 2

Author(s):

K. A. Shahin ◽

F. Abd El Azeem

Keyword(s):

Body Weight ◽

Body Fat ◽

Broiler Chickens ◽

High Protein ◽

High Fiber ◽

Fat Depots ◽

Low Protein ◽

Live Body Weight ◽

Total Body Fat ◽

Total Body

Abstract. The effects of breed (Hubbard and Anak), sex and diet (two levels of protein (high or low) with two levels of crude fiber (low or high) at each level of protein) on fat yields and partitioning among the depots were studied. No significant differences were found between breeds in fat yields and in fat partitioning among the major fat depots. Expressed as a percentage of live body weight, females had a greater percentage of non-carcass fat, carcass fat and total body fat than males. Females tended to partition more of their fat to non-carcass fat, whereas males tended to partition more of their fat to carcass fat. The effects of diet were consistent over the breeds and for all fatness traits. Non-carcass fat, carcass fat and total body fat yields were greatly depressed and favorable fat partition between depots was achieved through feeding birds high protein- high fiber diets. These birds tended to partition more of their fat to carcass fat depots (more valuables) and less to non-carcass fat depots. Breed x sex, breed x diet and sex x diet interactions did not significantly influence most of fatness traits indicating that the factors under consideration act independently of each other. Significant sex x diet interactions was found for carcass fat and total body fat relative to live body weight: the sexual dimorphism in low protein diet is more pronounced than in high protein diets. The differences between sexes in their response to diet for these traits might have important implications.

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Abstract MP048: Ectopic Muscle and Liver Adiposity are Independently Associated with Type 2 Diabetes in African Ancestry Men

Circulation ◽

10.1161/circ.135.suppl_1.mp048 ◽

2017 ◽

Vol 135 (suppl_1) ◽

Author(s):

Iva Miljkovic ◽

Allison Kuipers ◽

J Jeffrey Carr ◽

James Terry ◽

Sangeeta Nair ◽

...

Keyword(s):

Type 2 Diabetes ◽

Skeletal Muscle ◽

Body Fat ◽

African Ancestry ◽

Ectopic Fat ◽

Fat Depots ◽

Total Body Fat ◽

Muscle Adiposity ◽

Total Body

Although obesity is a major driver of type 2 diabetes (T2D), many obese individuals do not develop T2D. Indeed, fat around and within non-adipose tissue organs (i.e., ectopic fat) is emerging as a strong risk factor for diabetes. The potential differential contribution of ectopic fat depots throughout the body on T2D risk is unclear because studies have mainly focused on visceral and/or liver fat. No study, to our knowledge, has addressed the potential independent association of visceral, liver, and skeletal muscle adiposity with T2D. Such studies are particularly needed among African ancestry populations, as generalized obesity and other risk factors do not appear to explain the high T2D burden in this population segment. To address this knowledge gap, we measured total body fat by DXA, and visceral, liver, and calf skeletal muscle adiposity by computed tomography in 490 Afro-Caribbean men, aged 50-91 years (mean age=64 years, mean BMI=27.5 kg/m 2 ). The prevalence of T2D in this population was 22.3%. We employed multiple logistic regression using total body fat percent and ectopic fat depots as predictors (Table). We found that each 7.9 HU decrease in liver attenuation (indicative of greater liver adiposity) was associated with a 33% increased odds of T2D (p=0.011). Similarly, each 4.2 mg/cm 3 decrease in muscle attenuation (indicative of greater intra-muscular adiposity) was associated with a 31% increased odds of T2D (p=0.04). These associations were independent of total and visceral adiposity. Our results support the “ectopic fat syndrome” theory, as opposed to the “portal theory”, in the pathogenesis of diabetes among African ancestry men. Longitudinal studies are needed to clarify the exact role of specific ectopic fat depots in T2D, particularly in high-risk African ancestry populations.

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