scholarly journals Acute fat loss does not affect bone mass

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marie K. Lagerquist ◽  
Karin L. Gustafsson ◽  
Petra Henning ◽  
Helen Farman ◽  
Jianyao Wu ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Bone Mass ◽  
Fat Mass ◽  
Tissue Loss ◽  
Obese Mice ◽  
Long Term Effects ◽  
High Bone Mass ◽  
Age Related ◽  
Total Fat ◽  
Old Mice

AbstractObesity has previously been thought to protect bone since high body weight and body mass index are associated with high bone mass. However, some more recent studies suggest that increased adiposity negatively impacts bone mass. Here, we aimed to test whether acute loss of adipose tissue, via adipocyte apoptosis, alters bone mass in age-related obese mice. Adipocyte apoptosis was induced in obese male FAT-ATTAC mice through AP20187 dimerizer-mediated activation of caspase 8 selectively in adipocytes. In a short-term experiment, dimerizer was administered to 5.5 month-old mice that were terminated 2 weeks later. At termination, the total fat mass weighed 58% less in dimerizer-treated mice compared with vehicle-treated controls, but bone mass did not differ. To allow for the detection of long-term effects, we used 9-month-old mice that were terminated six weeks after dimerizer administration. In this experiment, the total fat mass weighed less (− 68%) in the dimerizer-treated mice than in the controls, yet neither bone mass nor biomechanical properties differed between groups. Our findings show that adipose tissue loss, despite the reduced mechanical loading, does not affect bone in age-related obese mice. Future studies are needed to test whether adipose tissue loss is beneficial during more severe obesity.

scholarly journals Body Composition And Bone Mineral Differences According to Lamin A (LMNA) Genotype in Familial Partial Lipodystrophy Type 2

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A271-A271
Author(s):  
Maria Cristina Foss de Freitas ◽  
Baris Akinci ◽  
Callie Corsa ◽  
Amy E Rothberg ◽  
Ormond A MacDougald ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Bone Mass ◽  
Bone Mineral ◽  
Fat Mass ◽  
Hot Spot ◽  
Lmna Gene ◽  
Mineral Density ◽  
Partial Lipodystrophy ◽  
Familial Partial Lipodystrophy ◽  
Total Fat

Abstract Phenotypic heterogeneity is well known in Familial Partial Lipodystrophy Type 2 (FPLD2), a rare form of adipose tissue disorder caused by pathogenic mutations in LMNA gene. Animal studies from our group have identified an association between adipose tissue loss and an increase in bone mineral density (BMD) in a mouse model with adipose tissue specific knockout of LMNA gene. Aiming to translate this observation to patients with FPLD2, we analyzed body composition data obtained by dual X-ray absorptiometry from 61 patients diagnosed with FPLD2 and 61 individuals with no diagnosis of FPLD (nFPLD) matched for sex, age and body mass index. As expected, we observed lower total fat mass in FPLD2 patients compared to nFPLD (15.8±9.3 kg vs. 28.5±12.4 kg, p=0.001), as well as lower fat mass in regions of arms, legs and trunk. Interestingly, patients with FPLD2 showed lower bone mineral density (BMD) compared to nFPLD 1.0±0.2 g/cm3 vs 1.2±0.1 g/cm3, p=0.01) and lower t-score (0.2±1.8 vs.1.5±1.2). We then aimed to determine if the patients with FPLD2 displayed differences with respect to genotype. For these analyses, the FPLD2 group was divided according to the pathogenic variant; 42 with mutations on the hot spot codon of the LMNA gene (R482: 50.2 ± 164.8 years, 76% women) and 19 with non-hot spot codon mutations (nR482: 44.8 ± 12.8 years, 78% women). Patients in the R482 group were older when they were first diagnosed with lipodystrophy (39.6 ± 18.6 years vs. 36.5 ± 12.3 years, p=0.05). Also, nR482 group presented with more progeroid characteristics. Patients in n-R482 group also had lower weight compared to R482 and nFPLD groups (64.4±14.4 vs. 73.3±18.5 and 77.6±16.6 kg, p=0.01), as well as lower total fat mass (15.3±5.1 vs. 15.8±9.3 and 25.7±11.4 kg, p=0.01) and fat mass ratio (5.8±1.9 vs. 5.9±3.1 and 9.0±4.1, p= 0.01). Control group bone mass was significantly higher in arms, legs and trunk compared to the R482 and nR482 groups. Moreover, the R482 group had lower bone mass in the legs compared to nR482 (690.5±227.2 vs.703.5±95.3 g, p=0.01), while showing higher trunk bone mass (676.4±266.7 vs. 674.1±79.3, p=0.04), in addition to greater fat mass in the legs (3.3±1.6 vs. 2.6±0.7 kg, p=0.05) and trunk areas (10.3±6.1 vs. 10.0±4.2 kg, p=0.03). There were no differences in total bone mass, BMD, and t-scores, according to genotype. Our data showed more fat preservation in LMNA R482 than nR482, presumably leading to a later lipodystrophy diagnosis. Furthermore, bone mass in different regions may be affected by LMNA genotype; however, more studies are needed to define the bone phenotype and fracture risk in FPLD2 population fully.

scholarly journals Testosterone therapy decreases subcutaneous fat and adiponectin in aging men

2012 ◽  
Vol 166 (3) ◽  
pp. 469-476 ◽  
Author(s):  
L Frederiksen ◽  
K Højlund ◽  
D M Hougaard ◽  
T H Mosbech ◽  
R Larsen ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Fat Mass ◽  
Subcutaneous Fat ◽  
Fat Distribution ◽  
Controlled Study ◽  
Testosterone Therapy ◽  
Testosterone Levels ◽  
Bioavailable Testosterone ◽  
Aging Men ◽  
Total Fat

ObjectiveTestosterone therapy increases lean body mass and decreases total fat mass in aging men with low normal testosterone levels. The major challenge is, however, to determine whether the metabolic consequences of testosterone therapy are overall positive. We have previously reported that 6-month testosterone therapy did not improve insulin sensitivity. We investigated the effect of testosterone therapy on regional body fat distribution and on the levels of the insulin-sensitizing adipokine, adiponectin, in aging men with low normal bioavailable testosterone levels.DesignA randomized, double-blinded, placebo-controlled study on 6-month testosterone treatment (gel) in 38 men, aged 60–78 years, with bioavailable testosterone <7.3 nmol/l, and a waist circumference >94 cm.MethodsCentral fat mass (CFM) and lower extremity fat mass (LEFM) were measured by dual X-ray absorptiometry. Subcutaneous abdominal adipose tissue (SAT), visceral adipose tissue (VAT), and thigh subcutaneous fat area (TFA) were measured by magnetic resonance imaging. Adiponectin levels were measured using an in-house immunofluorometric assay. Coefficients (b) represent the placebo-controlled mean effect of intervention.ResultsLEFM was decreased (b=−0.47 kg, P=0.07) while CFM did not change significantly (b=−0.66 kg, P=0.10) during testosterone therapy. SAT (b=−3.0%, P=0.018) and TFA (b=−3.0%, P<0.001) decreased, while VAT (b=1.0%, P=0.54) remained unchanged. Adiponectin levels decreased during testosterone therapy (b=−1.3 mg/l, P=0.001).ConclusionTestosterone therapy decreased subcutaneous fat on the abdomen and lower extremities, but visceral fat was unchanged. Moreover, adiponectin levels were significantly decreased during testosterone therapy.

scholarly journals Increasing Dietary Fish Oil Reduces Adiposity and Mitigates Bone Deterioration in Growing C57BL/6 Mice Fed a High-Fat Diet

2019 ◽  
Vol 150 (1) ◽  
pp. 99-107 ◽  
Author(s):  
Jay J Cao ◽  
Brian R Gregoire ◽  
Kim G Michelsen ◽  
Matthew J Picklo
Keyword(s):  
Adipose Tissue ◽  
Bone Mass ◽  
Fish Oil ◽  
High Fat Diet ◽  
Bone Structure ◽  
Tartrate Resistant Acid Phosphatase ◽  
Serum Concentrations ◽  
Obese Mice ◽  
High Fat ◽  
Long Chain

ABSTRACT Background Intake of total fat is linked to obesity and inversely associated with bone density in humans. Epidemiologic and animal studies show that long-chain n–3 (ω-3) PUFAs supplied as fish oil (FO) are beneficial to skeletal health. Objective This study tested the hypothesis that increasing dietary FO would decrease adiposity and improve bone-related outcomes in growing obese mice. Methods Male C57BL/6 mice at 6 wk old were assigned to 6 treatment groups and fed either a normal-fat diet (3.85 kcal/g and 10% energy as fat) or a high-fat diet (HF; 4.73 kcal/g and 45% energy as fat) containing either 0%, 3%, or 9% energy as FO (0FO, 3FO, and 9FO, respectively) ad libitum for 6 mo. Bone structure, body composition, and serum bone-related cytokines were measured. Results The HF diet increased the expression of the adipose tissue tumor necrosis factor α (Tnfa) and serum concentrations of leptin and tartrate-resistant acid phosphatase (TRAP), and decreased serum concentrations of osteocalcin and bone-specific alkaline phosphatase (P &lt; 0.05). FO decreased fat mass (P &lt; 0.05), serum TRAP (P &lt; 0.05), and adipose tissue Tnfa expression (P &lt; 0.01). Bone content of long-chain n–3 PUFAs was increased and n–6 PUFAs were decreased with the elevation in dietary FO content (P &lt; 0.01). Compared with mice fed 9FO, animals fed 3FO had higher femoral bone volume/total volume (25%), trabecular number (23%), connectivity density (82%), and bone mass of second lumbar vertebrae (12%) and lower femoral trabecular separation (−19%). Mice fed the 3FO HF diet had 42% higher bone mass than those fed the 0FO HF diet. Conclusions These data indicate increasing dietary FO ≤3% energy can decrease adiposity and mitigate HF diet–induced bone deterioration in growing C57BL/6 mice possibly by reducing inflammation and bone resorption. FO at 9% diet energy had no further beneficial effects on bone of obese mice.

scholarly journals Decreasing the Ratio of Dietary Linoleic to α-Linolenic Acid from 10 to 4 by Changing Only the Former Does Not Prevent Adiposity or Bone Deterioration in Obese Mice

2020 ◽  
Vol 150 (6) ◽  
pp. 1370-1378 ◽  
Author(s):  
Jay J Cao ◽  
Brian R Gregoire ◽  
Kim G Michelsen ◽  
Matthew J Picklo Sr
Keyword(s):  
Bone Mass ◽  
Linolenic Acid ◽  
Fat Mass ◽  
Bone Structure ◽  
Structural Parameters ◽  
Tartrate Resistant Acid Phosphatase ◽  
Low Grade ◽  
Obese Mice ◽  
Treatment Groups ◽  
Serum Trap

ABSTRACT Background Linoleic acid (LA; 18:2n–6) has been considered to promote low-grade chronic inflammation and adiposity. Studies show adiposity and inflammation are inversely associated with bone mass. Objectives This study tested the hypothesis that decreasing the dietary ratio of LA to α-linolenic acid (ALA, 18:3n–3), while keeping ALA constant, mitigates high-fat diet (HF)-induced adiposity and bone loss. Methods Male C57BL/6 mice at 6 wk old were assigned to 4 treatment groups and fed 1 of the following diets ad libitum for 6 mo: a normal-fat diet (NF; 3.85 kcal/g and 10% energy as fat) with the ratio of the PUFAs LA to ALA at 6; or HFs (4.73 kcal/g and 45% energy as fat) with the ratio of LA to ALA at 10:1, 7:1, or 4:1, respectively. ALA content in the diets was kept the same for all groups at 1% energy. Bone structure, body composition, bone-related cytokines in serum, and gene expression in bone were measured. Data were analyzed using 1-factor ANOVA. Results Compared with those fed the NF, mice fed the HFs had 19.6% higher fat mass (P &lt; 0.01) and 13.5% higher concentration of serum tartrate-resistant acid phosphatase (TRAP) (P &lt; 0.05), a bone resorption cytokine. Mice fed the HFs had 19.5% and 12.2% lower tibial and second lumbar vertebral bone mass, respectively (P &lt; 0.01). Decreasing the dietary ratio of LA to ALA from 10 to 4 did not affect body mass, fat mass, serum TRAP and TNF-α, or any bone structural parameters. Conclusions These data indicate that decreasing the dietary ratio of LA to ALA from 10 to 4 by simply reducing LA intake does not prevent adiposity or improve bone structure in obese mice.

scholarly journals Association between Interleukin-15 and Obesity: Interleukin-15 as a Potential Regulator of Fat Mass

2008 ◽  
Vol 93 (11) ◽  
pp. 4486-4493 ◽  
Author(s):  
Anders Rinnov Nielsen ◽  
Pernille Hojman ◽  
Christian Erikstrup ◽  
Christian Philip Fischer ◽  
Peter Plomgaard ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Skeletal Muscle ◽  
Adipose Tissue ◽  
Fat Mass ◽  
Negative Association ◽  
Tissue Mass ◽  
Adipose Tissue Mass ◽  
Interleukin 15 ◽  
Total Fat

Objective: IL-15 decreases lipid deposition in preadipocytes and decreases the mass of white adipose tissue in rats, indicating that IL-15 may take part in regulating this tissue. IL-15 is expressed in human skeletal muscle and skeletal muscle may be a source of plasma IL-15 and in this way regulate adipose tissue mass. Design: The relation between skeletal muscle IL-15 mRNA expression, plasma IL-15, and adipose tissue mass was studied in 199 humans divided into four groups on the basis of obesity and type 2 diabetes. Furthermore, using a DNA electrotransfer model, we assessed the effect of IL-15 overexpression in skeletal muscle of mice. Results: In humans, multiple regression analysis showed a negative association between plasma IL-15 and total fat mass (P &lt; 0.05), trunk fat mass (P &lt; 0.01), and percent fat mass (P &lt; 0.05), independent of type 2 diabetes. Negative associations were also found between muscle IL-15 mRNA and obesity parameters. IL-15 overexpression in skeletal muscle of mice reduced trunk fat mass but not sc fat mass. Conclusions: Our results indicate that IL-15 may be a regulator of trunk fat mass.

scholarly journals Cortical bone gain following loading is site-specifically enhanced by prior and concurrent disuse in aged male mice

2019 ◽  
Author(s):  
Gabriel Galea ◽  
Peter J Delisser ◽  
Lee Meakin ◽  
Lance E Lanyon ◽  
Joanna S Price ◽  
...  
Keyword(s):  
Bone Mass ◽  
Cortical Bone ◽  
List Type ◽  
Male Mice ◽  
Site Specific ◽  
Female Mice ◽  
Age Related ◽  
Sciatic Neurectomy ◽  
Bone Gain ◽  
Old Mice

AbstractThe primary aim of bone anabolic therapies is to strategically increase bone mass in skeletal regions likely to experience high strains. This is naturally achieved by mechanical loading of the young healthy skeleton. However, these bone anabolic responses fail with age. Here, we applied site specificity analysis to map regional differences in bone anabolic responses to axial loading of the tibia (tri-weekly, for two weeks) between young (19-week-old) and aged (19-month-old), male and female mice. Loading increased bone mass specifically in the proximal tibia in both sexes and ages. Young female mice gained more cortical bone than young males in specific regions of the tibia. However, these site-specific sex difference were lost with age such that bone gain following loading was not significantly different between old males and females. Having previously demonstrated that prior and concurrent disuse enhances bone gain following loading in old females, we established whether this “rescue” is sex-specific. Old male mice were subjected to sciatic neurectomy or sham surgery, and tri-weekly loading was initiated four days after surgery. Disuse augmented cortical bone gain in response to loading in old male mice, but only in the regions of the tibia which were load-responsive in the young. Increased understanding of how locally-activated load-responsive processes lead to site-specific bone formation, and how the age-related diminution of these processes can be site-specifically enhanced by disuse, may lead to the next generation of strategic bone anabolic therapies.HighlightsSex differences in cortical tissue area of young and old mice are not site-specificThe loading response in young, but not old, mice is sex- and site-specificThe cortical loading response is site-specifically enhanced by disuse in old mice of both sexesThe trabecular loading response can be rescued by disuse in old male, but not female, mice

scholarly journals Dysregulation of adipose ILC2 underlies thermogenic failure in aging

2020 ◽  
Author(s):  
Emily L. Goldberg ◽  
Irina Shchukina ◽  
Yun-Hee Youm ◽  
Christina D. Camell ◽  
Tamara Dlugos ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Core Body Temperature ◽  
Lymphoid Cells ◽  
Adipose Tissue Inflammation ◽  
Age Related ◽  
Core Body ◽  
Old Mice ◽  
Functional Defects ◽  
Age Related Changes

AbstractAging impairs the integrated immunometabolic responses which have evolved to maintain core body temperature in homeotherms to survive cold-stress, infections, and dietary restriction. Adipose tissue inflammation regulates the thermogenic stress response but how adipose tissue-resident cells instigate thermogenic failure in aged are unknown. Here, we define alterations in the adipose-resident immune system and identify that type 2 innate lymphoid cells (ILC2) are lost in aging. Restoration of ILC2 numbers in aged mice to levels seen in adults through IL-33 supplementation failed to rescue old mice from metabolic impairment and cold-induced lethality. Transcriptomic analyses revealed intrinsic defects in aged ILC2, and adoptive transfer of adult ILC2 are sufficient to protect old mice against cold. Thus, the functional defects in adipose ILC2 during aging drive thermogenic failure.One Sentence SummaryAge-related changes in adipose tissue drive reprogramming of ILC2 that leads to impaired cold tolerance

scholarly journals Bone mineral density and body composition in adolescents with failure to thrive

2010 ◽  
Vol 8 (2) ◽  
pp. 168-174
Author(s):  
Thiago Sacchetto de Andrade ◽  
Luiz Anderson Lopes ◽  
Marcelo de Medeiros Pinheiro ◽  
Vera Lucia Szejnfeld ◽  
José Augusto de Aguiar Carrazedo Taddei
Keyword(s):  
Bone Mineral Density ◽  
Body Composition ◽  
Bone Mass ◽  
Bone Mineral ◽  
Fat Mass ◽  
Failure To Thrive ◽  
Fat Free Mass ◽  
Z Score ◽  
Mineral Density ◽  
Total Fat

ABSTRACT Objective To evaluate bone mineral mass in adolescents with failure to thrive in relation to body composition. Methods A case control study involving 126 adolescents (15 to 19 years), in final puberty maturation being 76 eutrophic and 50 with failure to thrive (genetic or constitutional delay of growth), of matching ages, gender and pubertal maturation. The weight, height and calculated Z score for height/age and body mass index; bone mineral content, bone mineral density and adjusted bone mineral density were established for total body, lower back and femur; total fat-free mass and height-adjusted fat-free mass index, total fat mass and height-adjusted. The statistical analyses were performed using the Student's t-test (weight, height and body composition); Mann-Whitney test (bone mass) and multiple linear regression (bone mass determinants). Results weight, height and height/age Z-score were significantly higher among eutrophic subjects. Both groups did not show statistically significant differences for fat mass, percentage of fat mass, total fat mass height adjusted and fat-free mass index height sadjusted. However, total free fat maass was smaller for the failure to thrive group. Conclusions There was no statistically significant difference for bone mass measurements among adolescents with failure to thrive; however, the factors that determine bone mass formation should be better studied due to the positive correlation with free fat mass detected in these individuals.

scholarly journals Orexin Restores Aging-Related Brown Adipose Tissue Dysfunction in Male Mice

Endocrinology ◽  
2014 ◽  
Vol 155 (2) ◽  
pp. 485-501 ◽  
Author(s):  
Dyan Sellayah ◽  
Devanjan Sikder
Keyword(s):  
Adipose Tissue ◽  
Brown Adipose Tissue ◽  
Fat Mass ◽  
Core Body Temperature ◽  
Brown Adipocyte ◽  
Aged Mice ◽  
Age Related ◽  
Brown Adipose ◽  
The Impact

The aging process causes an increase in percent body fat, but the mechanism remains unclear. In the present study we examined the impact of aging on brown adipose tissue (BAT) thermogenic activity as potential cause for the increase in adiposity. We show that aging is associated with interscapular BAT morphologic abnormalities and thermogenic dysfunction. In vitro experiments revealed that brown adipocyte differentiation is defective in aged mice. Interscapular brown tissue in aged mice is progressively populated by adipocytes bearing white morphologic characteristics. Aged mice fail to mobilize intracellular fuel reserves from brown adipocytes and exhibit deficiency in homeothermy. Our results suggest a role for orexin (OX) signaling in the regulation of thermogenesis during aging. Brown fat dysfunction and age-related assimilation of fat mass were accelerated in mice in which OX-producing neurons were ablated. Conversely, OX injections in old mice increased multilocular morphology, increased core body temperature, improved cold tolerance, and reduced adiposity. These results argue that BAT can be targeted for interventions to reverse age-associated increase in fat mass.

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