Osteosarcopenic adiposity (OSA) phenotype and its connection with cardiometabolic disorders: Is there a cause-and-effect?

The objectives were to examine if there is a causal relationship between osteosarcopenic adiposity (OSA) syndrome (coexistence of osteopenia/osteoporosis, sarcopenia, and excess adiposity) and cardiometabolic disorders or if these disorders initiate the development of OSA and its worsening. The search was conducted in PubMed, Scopus, and Web of Science to include articles up to the end of 2023. Of n=539 articles retrieved, n=15 met the eligibility criteria. Only studies conducted in adults and with all three body composition compartments (bone, muscle/lean, adipose) measured were considered. The results revealed that several cardiometabolic disorders, namely, hypertension, dyslipidemia (elevated total and LDL-cholesterol, lower HDL-cholesterol), insulin resistance, hyperglycemia, lower serum vitamin D, and some inflammatory markers were accompanied by OSA. In most cases, the OSA phenotype was associated with worse outcomes than cases with healthy or less impaired body composition. Our initial questions about the reciprocal cause-and-effect relationships could be surmised with more certainty for the OSA and some cardiovascular risks (hypertension, dyslipidemia) and some metabolic abnormalities (several inflammatory markers). The results of this review underscore the importance of body composition in health and from a clinical perspective, all three body composition compartments should be measured by standardized technologies using regulated diagnostic criteria to identify OSA. Randomized trials and prospective studies in diverse groups of older and younger individuals are necessary to determine if the relationships between OSA and clinical endpoints are causal and reversible through intervention and to uncover the mechanisms.

Understanding the Consequences of Fatty Bone and Fatty Muscle: How the Osteosarcopenic Adiposity Phenotype Uncovers the Deterioration of Body Composition

Adiposity is central to aging and several chronic diseases. Adiposity encompasses not just the excess adipose tissue but also body fat redistribution, fat infiltration, hypertrophy of adipocytes, and the shifting of mesenchymal stem cell commitment to adipogenesis. Bone marrow adipose tissue expansion, inflammatory adipokines, and adipocyte-derived extracellular vesicles are central to the development of osteopenic adiposity. Adipose tissue infiltration and local adipogenesis within the muscle are critical in developing sarcopenic adiposity and subsequent poorer functional outcomes. Ultimately, osteosarcopenic adiposity syndrome is the result of all the processes noted above: fat infiltration and adipocyte expansion and redistribution within the bone, muscle, and adipose tissues, resulting in bone loss, muscle mass/strength loss, deteriorated adipose tissue, and subsequent functional decline. Increased fat tissue, typically referred to as obesity and expressed by body mass index (the latter often used inadequately), is now occurring in younger age groups, suggesting people will live longer with the negative effects of adiposity. This review discusses the role of adiposity in the deterioration of bone and muscle, as well as adipose tissue itself. It reveals how considering and including adiposity in the definition and diagnosis of osteopenic adiposity, sarcopenic adiposity, and osteosarcopenic adiposity will help in better understanding the pathophysiology of each and accelerate possible therapies and prevention approaches for both relatively healthy individuals or those with chronic disease.

Low Protein Intakes and Poor Diet Quality Associate with Functional Limitations in US Adults with Diabetes: A 2005-2016 NHANES Analysis

Type 2 diabetes is associated with an increased risk for sarcopenia. Moreover, sarcopenia correlates with increased risk for falls, fractures, and mortality. This study aimed to explore relationships among nutrient intakes, diet quality, and functional limitations in a sample of adults across levels of glycemic control. Data were examined from 23,487 non-institutionalized adults, 31 years and older, from the 2005–2016 National Health and Nutrition Examination Survey. Hemoglobin A1c (%) was used to classify level of glycemic control: non-diabetes (<5.7%); pre-diabetes (5.7–6.4%); diabetes (≥6.5%). Dietary data were collected from a single 24-h dietary recall. Participants were categorized as meeting or below the protein recommendation of 0.8 g/kg of body weight. Physical functioning was assessed across 19-discrete physical tasks. Adults below the protein recommendation consumed significantly more carbohydrate and had lower diet quality across all glycemic groups compared to those who met the protein recommendation (p < 0.001). Adults with diabetes who did not meet protein recommendations had significantly poorer diet quality and significantly higher mean number of functional limitations. A greater percent of adults with diabetes who did not meet the protein recommendation reported being physically limited for most activities, with more than half (52%) reporting limitations for stooping, crouching, and kneeling. This study underscores the potential for physical limitations associated with low protein intakes, especially in adults with diabetes. In the longer term, low protein intakes may result in increased risk of muscle loss, as protein intake is a critical nutritional factor for prevention of sarcopenia, functional limitations, and falls.

Poorer Diet Quality Observed Among US Adults With a Greater Number of Clinical Chronic Disease Risk Factors

Background

Obesity and chronic disease risk are significantly related to healthy lifestyle behavior, including dietary intakes. Further, the interrelated etiology of many chronic conditions supports the comorbidity in US adults to manage multiple diagnoses. The purpose of this study was to assess diet quality across varying numbers of existing conditions, including obesity, hypercholesterolemia, hyperglycemia, and hypertension.

Methods

Cross-sectional analysis of data from 17 356 adults aged 45 years and older from the 2005-2016 National Health and Nutrition Examination Survey were assessed for the presence of overweight or obesity (body mass index >25 kg/m²), hyperglycemia (glycated hemoglobin >5.7%), hypercholesterolemia (>200 mg/dL), and high blood pressure (>120/80 mm Hg). Overall diet quality was assessed using Healthy Eating Index 2015 scores computed from the intakes reported during the 24-hour dietary recall collected in the mobile examination center. The total score (range 0-100) is based on the sum of 13 subscales that represent concordance with the Dietary Guidelines for Americans.

Results

Few adults presented with no markers of chronic disease (n = 407), with other presenting 1 indicator (n = 1978), 2 indicators (n = 4614), 3 indicators (n = 6319), and all 4 indicators (4038). While there was no significant difference in mean energy intakes on the day of intake, those with all 4 markers of chronic disease had a significantly poorer diet quality (P < .001) and consumed significantly more saturated fat (P = .026), but significantly less total carbohydrates, dietary fiber, and added sugars (P < .005). While mean consumption of protein was lowest in those with more chronic conditions, the differences were not significant.

Conclusion

Overall dietary intakes from the day of intake indicated that those with a greater number of chronic conditions presented with poorer overall dietary intakes. The foundational intervention strategy across all evidence-based treatment strategies is the promotion of healthy lifestyle behaviors.

POORER DIET QUALITY OBSERVED IN OLDER ADULTS WITH A GREATER NUMBER OF CHRONIC DISEASES

Unhealthy lifestyle behaviors, including poor diet over many years, contribute to the development of chronic diseases, especially overweight/obesity, hyperglycemia, hypercholesterolemia and hypertension. Because poor diet is common to the diseases, it supports the notion of concurrently managing comorbidities through improved diet. Therefore, the purpose of this study was to assess differences in diet quality and nutrient intakes, in adults aged 65 years and older, by the number of chronic conditions. Data from 7,169 adults, aged 65 years and older, from the 2005-2016 National Health and Nutrition Examination Survey were assessed for selected chronic diseases from laboratory data: overweight/obesity (body mass index >25); hyperglycemia (glycated hemoglobin >5.7%); hypercholesterolemia (total cholesterol >200 mg/dL); hypertension (blood pressure >120/80 mmHg). The number of chronic diseases was computed per participant. Dietary intakes and diet quality score were assessed using 24-hour dietary recalls. Few adults had none of the selected chronic disease (n=79;1.4%), with others presenting 1 indicator (n=677;9.8%), 2 indicators (n=1,762;25%), 3 indicators (n=2,741;38.9%) and all 4 indicators (n=1,910;24.9%). Diet quality was significantly lower in those with three or four chronic diseases (P<0.001). Adults without any of the selected chronic diseases consumed significantly more calories, carbohydrates, fiber and added sugars, as well as folate, vitamin C and calcium than those with chronic diseases (P<0.001). Overall, dietary intakes from the day of intake were different for those with or without chronic diseases. These findings strengthen the need to promote healthy eating in older adults with one or more chronic conditions to help improve outcomes.

Osteosarcopenic Obesity: Current Knowledge, Revised Identification Criteria and Treatment Principles

Osteosarcopenic obesity (OSO) syndrome describes the simultaneous deterioration of bone, muscle and excess fat, resulting in reduced functionality and systemic metabolic dysregulation. The key component contributing to this may be ectopic fat in the viscera, bone and muscle. OSO research to date is summarized, and the revised criteria for its identification for research purposes are reviewed and proposed, including new criteria to assess visceral fat in males and females. Finally, nutritional and physical activity recommendations are consolidated into a treatment algorithm, which can be validated in future studies and which may also be applied to preventative management.

Utilizing Dietary Nutrient Ratios in Nutritional Research: Expanding the Concept of Nutrient Ratios to Macronutrients

We recently showed that using micronutrient ratios in nutritional research might provide more insights into how diet affects metabolism and health outcomes, based on the notion that nutrients, unlike drugs, are not consumed one at a time and do not target a single metabolic pathway. In this paper, we present a concept of macronutrient ratios, including intra- and inter-macronutrient ratios. Macronutrient intakes from food only, from the What We Eat in America website (summarized National Health and Nutrition Examination Survey data) were transposed into Microsoft Excel to generate ratios. Overall, the dietary ratios of macronutrients may be more revealing and useful in epidemiology and in basic nutritional research than focusing on individual protein, fat, and carbohydrate intakes. While macronutrient ratios may be applied to all types of nutritional research, nutritional epidemiology, and, ultimately, dietary guidelines, the methodology required has not been established yet. In the meantime, intra- and inter-macronutrient ratios may serve as a measure of individual and total macronutrient quality.

Low Dietary Protein Intakes and Associated Dietary Patterns and Functional Limitations in an Aging Population: A NHANES analysis

OBJECTIVE

To investigate protein intakes across demographic characteristics in relation to dietary patterns and functional outcomes in older adults.

DESIGN

Observational and cross-sectional study.

SETTING

Non-institutionalized participants from the 2005-2014 National Health and Nutrition Examination Survey.

PARTICIPANTS

Data from 11,680 adults were categorized into 51-60 years (n= 4,016), 61-70 years (n=3,854), and 71 years and older (n=3,810) for analysis.

MEASUREMENTS

Adults were stratified by meeting or not meeting the protein recommendation (0.8 g/kg/d) to compare demographics, diet quality with Healthy Eating Index-2015, functional limitations, and other dietary intakes. Dietary recalls were collected using the multiple pass method. Data analyses were weighted to create a nationally-representative sample.

RESULTS

Dietary protein intakes were significantly lower in older age groups, with up to 46% of the oldest adults not meeting the protein intake recommendation. Participants consuming protein below the recommended intake level had significantly poorer diet quality across all age groups (P<0.01), however, overall diet quality was better in older adults. Those not meeting the protein recommendation were more likely to have intakes of other nutrients below recommended levels. Those below the protein recommendation had significantly more functional limitations across all age groups, while grip strength was significantly lower in those over 70 years old.

CONCLUSION

Lower protein intakes, and lower diet quality and physical functioning are related in an aging population. Meeting the protein recommendation was linked to better overall diet quality and may be protective of lean mass; therefore, evaluation of individual characteristics which may affect protein intakes is crucial in supporting older adults to meet their protein needs.

AdNut study: effectiveness of a high calorie and protein oral nutritional supplement with β-hydroxy-β-methylbutyrate in an older malnourished population in usual clinical practice

Objective

To evaluate the effectiveness of a high calorie and protein, β-hydroxy-β-methylbutyrate containing oral nutritional supplement (HP-HMB-ONS), on nutritional status, activities of daily living and quality of life (QoL) in old malnourished subjects.

Methods

We conducted an observational, prospective, open label, multicenter study. Participants were > 65 years, undernourished or at nutritional risk [Nutrition Risk Score (NRS) ≥ 3] and had been included on an ONS (HP-HMB-ONS twice daily for 12 weeks) per standard of care. Visits at baseline (V1), 6 weeks (V2) and 12 weeks (V3) were performed. The primary endpoints were gain of body weight, change in body mass index (BMI) and NRS 2002 index. Data from QoL (EQ-5D-3L) and activities of daily living (Katz index) were also collected.

Results

A total of 235 participants were included in the study. Of these 148 took at least a 75% of the HP-HMB-ONS and were included in the analysis (per protocol); median age was 80.0 (SD:8.3) years, 65.5% (n = 97) were female, 67.6% (n = 100) had 2 or more diseases. At V3, a statistically significant increase in weight (2.1 kg; SD: 3.8) (p < 0.001) and BMI (0.8 kg/m²; SD: 1.45) were found compared to V1, whereas NRS 2002 values decreased by 0.9 (SD: 1.2). A significant (p < 0.001) improvement in Katz index (mean change = 0.3; SD:1.4) and EQ-5D scoring (mean change = 0.5; SD:1.9) compared to V1, were also reported.

Conclusions

The results suggest that administration of a HP-HMB-ONS improve the nutritional status and may led to a significant improvement in patients' activities of daily living and QoL, independent of baseline BMI.

Macronutrient Intake and Distribution in the Etiology, Prevention and Treatment of Osteosarcopenic Obesity

BACKGROUND

Osteosarcopenic obesity, the combined deterioration of bone, muscle and fat tissues, could become the ultimate trajectory of aging. Aging stem cells are deregulated by low-grade chronic inflammation and possibly by diet. The metabolic shift of stem cells towards adipogenesis results in osteo obesity, sarco obesity and obesity. Macronutrients have numerous physiological functions but are regarded mainly for their energy contribution. Currently, no nutritional causes or treatment/prevention guidelines exist for osteosarcopenic obesity.

OBJECTIVE

The aim of this review is to assemble the evidence to elucidate if the macronutrient composition of the Western diet has an effect on the development of osteosarcopenic obesity. In view of the role of brain in locomotion a section examining the macronutrients as possible modulators of brain functioning was included.

METHOD

An extensive literature search of PubMed and Medline was conducted for human data using combinations and synonyms of osteoporosis, sarcopenia and obesity, and energy, carbohydrate, protein and lipid, and brain. US National Health and Nutrition Examination Survey (NHANES) food intake data from 2002-2012 were obtained and transposed to Microsoft Excel for analysis.

RESULTS

NHANES data showed that energy imbalances in aging, excess high glycemic carbohydrate, lower protein intakes and low long chain polyunsaturated fat intakes may contribute to osteosarcopenic obesity. 135 articles were included in the review.

CONCLUSION

Early humans probably consumed a diet closer to what the human body was designed for; however, we do not know the ideal energy and macronutrient proportions for optimal health or for preventing/treating aging and osteosarcopenic obesity.

Role of Dietary Antioxidants in the Preservation of Vascular Function and the Modulation of Health and Disease

In vascular diseases, including hypertension and atherosclerosis, vascular endothelial dysfunction (VED) occurs secondary to altered function of endothelial nitric oxide synthase (eNOS). A novel redox regulated pathway was identified through which eNOS is uncoupled due to S-glutathionylation of critical cysteine residues, resulting in superoxide free radical formation instead of the vasodilator molecule, nitric oxide. In addition, the redox sensitive cofactor tetrahydrobiopterin, BH₄, is also essential for eNOS coupling. Antioxidants, either individually or combined, can modulate eNOS uncoupling by scavenging free radicals or impairing specific radical generating pathways, thus preventing oxidative stress and ameliorating VED. Epidemiological evidence and dietary guidelines suggest that diets high in antioxidants, or antioxidant supplementation, could preserve vascular health and prevent cardiovascular diseases (CVDs). Therefore, the purpose of this review is to highlight the possible role of dietary antioxidants in regulating eNOS function and uncoupling which is critical for maintenance of vascular health with normal blood flow/circulation and prevention of VED. We hypothesize that a conditioned dietary approach with suitable antioxidants may limit systemic oxidation, maintain a beneficial ratio of reduced to oxidized glutathione, and other redox markers, and minimize eNOS uncoupling serving to prevent CVD and possibly other chronic diseases.

Effects of β-hydroxy-β-methylbutyrate on skeletal muscle mitochondrial content and dynamics, and lipids after 10 days of bed rest in older adults

Loss of muscle mass during periods of disuse likely has negative health consequences for older adults. We have previously shown that β-hydroxy-β-methylbutyrate (HMB) supplementation during 10 days of strict bed rest (BR) attenuates the loss of lean mass in older adults. To elucidate potential molecular mechanisms of HMB effects on muscle during BR and resistance training rehabilitation (RT), we examined mediators of skeletal muscle mitochondrial dynamics, autophagy and atrophy, and intramyocellular lipids. Nineteen older adults (60-76 yr) completed 10 days BR followed by 8-wk RT rehabilitation. Subjects were randomized to either HMB (3 g/day HMB; n = 11) or control (CON; n = 8) groups. Skeletal muscle cross-sectional area (CSA) was determined by histology from percutaneous vastus lateralis biopsies. We measured protein markers of mitochondrial content [oxidative phosphorylation (OXPHOS)], fusion and fission (MFN2, OPA1, FIS1, and DRP1), autophagy (Beclin1, LC3B, and BNIP3), and atrophy [poly-ubiquinated proteins (poly-ub)] by Western blot. Fatty acid composition of several lipid classes in skeletal muscle was measured by infusion-MS analysis. Poly-ub proteins and OXPHOS complex I increased in both groups following BR (P < 0.05, main effect for time), and muscle triglyceride content tended to increase following BR in the HMB group (P = 0.055). RT rehabilitation increased OXPHOS complex II protein (P < 0.05), and total OXPHOS content tended (P = 0.0504) to be higher in HMB group. In addition, higher levels of DRP1 and MFN2 were maintained in the HMB group after RT (P < 0.05). BNIP3 and poly-ub proteins were significantly reduced following rehabilitation in both groups (P < 0.05). Collectively, these data suggest that HMB influences mitochondrial dynamics and lipid metabolism during disuse atrophy and rehabilitation.NEW & NOTEWORTHY Mitochondrial content and dynamics remained unchanged over 10 days of BR in older adults. HMB stimulated intramuscular lipid storage as triacylglycerol following 10 days of bed rest (BR) and maintained higher mitochondrial OXPHOS content and dynamics during the 8-wk resistance exercise rehabilitation program.

Aging human body: changes in bone, muscle and body fat with consequent changes in nutrient intake

Aging affects almost all physiological processes, but changes in body composition and body phenotype are most observable. In this review, we focus on these changes, including loss of bone and muscle and increase in body fat or redistribution of the latter, possibly leading to osteosarcopenic obesity syndrome. We also address low-grade chronic inflammation, prevalent in aging adults and a cause of many disorders including those associated with body composition. Changes in dietary intake and nutritional requirements of older individuals, that all may lead to some disturbances on tissue and organ levels, are discussed as well. Finally, we discuss the hormonal changes in the aging body, considering each of the tissues, bone, muscle and fat as separate endocrine organs, but yet in the continuous interface and communication with each other. Although there are still many unanswered questions in this field, this review will enable the readers to better understand the aging human body and measures needing to be implemented toward reducing impaired health and disability in older individuals.

Osteosarcopenic obesity in women: impact, prevalence, and management challenges

Osteosarcopenic obesity syndrome (OSO) has recently been identified as a condition encompassing osteopenia/osteoporosis, sarcopenia and obesity. OSO is especially deleterious in older adults (even if they are not obese by conventional measures), due to age-related redistribution of fat and its infiltration into bone and muscle. Osteoporosis and bone fractures in elderly increase the risk of sarcopenia, which, through decreased mobility, increases the risk of more falls and fractures, creating a vicious cycle. Obesity plays a dual role: to a certain extent, it promotes bone and muscle gains through mechanical loading; in contrast, increased adiposity is also a source of pro-inflammatory cytokines and other endocrine factors that impair bone and muscle. As the elderly population increases, changes in lifestyle to delay the onset of OSO, or prevent OSO, are warranted. Among these changes, dietary patterns and physical activity modifications are the first ones to be implemented. The typical Western diet (and lifestyle) promotes several chronic diseases including OSO, by facilitating a pro-inflammatory state, largely via the imbalance in omega-6/omega-3 fatty acid ratio and low-fiber and high-processed food consumption. Nutritional modifications to prevent and/or alleviate the OSO syndrome include adequate intake of protein, calcium, magnesium and vitamin D and increasing consumptions of foods containing omega-3 polyunsaturated fatty acids and fiber. Certain types of physical activity, often decreased in overweight/obese women and in elderly, might preserve bone and muscle, as well as help in reducing body fat accrual and fat infiltration. Habitual daily activities and some alternative modes of exercise may be more appropriate for older adults and play a crucial role in preventing bone and muscle loss and maintaining optimal weight. In conclusion, older adults who suffer from OSO syndrome may benefit from combined efforts to improve diet and physical activity, and such recommendations should be fostered as part of public health programs.

Can Unconventional Exercise be Helpful in the Treatment, Management and Prevention of Osteosarcopenic Obesity?

BACKGROUND

Body composition changes occur with aging; bone and muscle mass decrease while fat mass increases. The collective term for these changes is osteosarcopenic obesity. It is known that conventional resistance exercise programs build/maintain lean mass and reduce fat mass. However, unconventional (to Western society/medicine) forms of exercise may be viable for the treatment/prevention of osteosarcopenic obesity.

OBJECTIVE

The purpose of this review is to assess relatively unconventional exercises for their efficacy in maintaining/improving bone and muscle mass and reducing fat mass.

METHOD

A literature search for unconventional exercise showed Tai Chi, yoga, Pilates, whole body vibration, electrical stimulation of muscle, and the Alexander Technique were considered alternative/ unconventional. A PubMed and Medline search for human data using combinations and synonyms of osteoporosis, sarcopenia and obesity, and each exercise was then conducted.

RESULTS

Tai Chi, yoga, and Pilates, in addition to whole body vibration, electrical stimulation of muscle, and the Alexander Technique are all considered low impact. Tai Chi, yoga, and Pilates not only physically support the body, but also increase balance and quality of life. The devices showed promise in reducing or preventing muscle atrophy in older people that are unable to perform conventional exercises.

CONCLUSION

Any exercise, conventional or otherwise, especially in sedentary older people, at risk of, or diagnosed with osteosarcopenic obesity may be better than none. Exercise prescriptions should suit the patient and the desired outcomes; the patient should not be forced to fit an exercise prescription, so all potential forms of exercise should be considered.

Micronutrient Intake in the Etiology, Prevention and Treatment of Osteosarcopenic Obesity

BACKGROUND

Aging, chronic inflammation and/or many chronic conditions may result in loss of bone, loss of muscle and increased adiposity, manifested either overtly (overweight) or furtively as fat infiltration into bone and muscle. This combined condition has been identified as osteosarcopenic obesity. Micronutrients are required, not just to prevent deficiency diseases, but for optimal health and metabolic homeostasis. Further, micronutrients have multifunctional roles in the body. However, it is unknown if the micronutrient intake of the Western diet contributes to bone and muscle loss, increased adiposity, and ultimately osteosarcopenic obesity.

OBJECTIVE

The aim of this review is to examine the micronutrient intake using US National Health and Nutrition Examination Survey (NHANES) data, and explore if the insufficiencies, or excesses present contribute to the development of osteosarcopenic obesity in aging.

METHOD

First NHANES food intake data from 2002-2012 were obtained and transposed to Microsoft Excel for analysis. A literature search of PubMed and Medline for human data using combinations and synonyms of osteoporosis, sarcopenia and obesity, and each mineral and vitamin indicated as insufficient by NHANES.

RESULTS

NHANES data suggested phosphorus, calcium, magnesium, potassium, iron, and vitamins B6/B12/C/A/D/E and K were candidates for further evaluation. 170 articles were included.

CONCLUSION

While chronic single/multiple micronutrient insufficiency/excess is not studied in clinical trials, NHANES data suggest that they have existed for at least a decade. Examining the status and roles of those nutrients may be important to understanding the health issues associated with Western-type diets, including development of osteosarcopenic obesity.

Osteosarcopenic obesity is associated with reduced handgrip strength, walking abilities, and balance in postmenopausal women

We determined the prevalence of osteosarcopenic obesity (loss of bone and muscle coexistent with increased adiposity) in overweight/obese postmenopausal women and compared their functionality to obese-only women. Results showed that osteosarcopenic obese women were outperformed by obese-only women in handgrip strength and walking/balance abilities indicating their higher risk for mobility impairments.

INTRODUCTION

Osteosarcopenic obesity (OSO) is a recently defined triad of osteopenia/osteoporosis, sarcopenia, and adiposity. We identified women with OSO in overweight/obese postmenopausal women and evaluated their functionality comparing them with obese-only (OB) women. Additionally, women with osteopenic/osteoporotic obesity (OO), but no sarcopenia, and those with sarcopenic obesity (SO), but no osteopenia/osteoporosis, were identified and compared. We hypothesized that OSO women will have the lowest scores for each of the functionality measures.

METHODS

Participants (n = 258; % body fat ≥35) were assessed using a Lunar iDXA instrument for bone and body composition. Sarcopenia was determined from negative residuals of linear regression modeled on appendicular lean mass, height, and body fat, using 20th percentile as a cutoff. Participants with T-scores of L1-L4 vertebrae and/or total femur <-1, but without sarcopenia, were identified as OO (n = 99) and those with normal T-scores, but with sarcopenia, as SO (n = 28). OSO (n = 32) included women with both osteopenia/osteoporosis and sarcopenia, while those with normal bone and no sarcopenia were classified as OB (n = 99). Functionality measures such as handgrip strength, normal/brisk walking speed, and right/left leg stance were evaluated and compared among groups.

RESULTS

Women with OSO presented with the lowest handgrip scores, slowest normal and brisk walking speed, and shortest time for each leg stance, but these results were statistically significantly different only from the OB group.

CONCLUSION

These findings indicate a poorer functionality in women presenting with OSO, particularly compared to OB women, increasing the risk for bone fractures and immobility from the combined decline in bone and muscle mass, and increased fat mass.

Interrelationship among muscle, fat, and bone: connecting the dots on cellular, hormonal, and whole body levels

While sarcopenia and sarcopenic obesity have been recognized in the last decade, a combined concept to include decreased muscle mass and strength, as well as decreased bone mass with coexistence of adiposity is discussed here. We introduce a new term, osteopenic obesity, and operationalize its meaning within the context of osteopenia and obesity. Next, we consolidate osteopenic obesity with the already existing and more familiar term, sarcopenic obesity, and delineate the resulting combined condition assigning it the term osteosarcopenic obesity. Identification and possible diagnosis of each condition are discussed, as well as the interactions of muscle, fat and bone tissues on cellular level, considering their endocrine features. Special emphasis is placed on the mesenchymal stem cell commitment into osteoblastogenic, adipogenic and myogenic lineages and causes of its deregulation. Based on the presented evidence and as expounded within the text, it is reasonable to say that under certain conditions, osteoporosis and sarcopenia could be the obesity of bone and muscle, respectively, with the term osteosarcopenic obesity as an encompassment for all.

Synergism of α-linolenic acid, conjugated linoleic acid and calcium in decreasing adipocyte and increasing osteoblast cell growth

Whole fat milk and dairy products (although providing more energy compared to low- or non-fat products), are good sources of α-linolenic acid (ALA), conjugated linoleic acid (CLA) and calcium, which may be favorable in modulating bone and adipose tissue metabolism. We examined individual and/or synergistic effects of ALA, CLA and calcium (at levels similar to those in whole milk/dairy products) in regulating bone and adipose cell growth. ST2 stromal, MC3T3-L1 adipocyte-like and MC3T3-E1 osteoblast-like cells were treated with: (a) linoleic acid (LNA):ALA ratios = 1-5:1; (b) individual/combined 80-90 % c9, t11 (9,11) and 5-10 % t10, c12 (10,12) CLA isomers; (c) 0.5-3.0 mM calcium; (d) combinations of (a), (b), (c); and (e) control. Local mediators, including eicosanoids and growth factors, were measured. (a) The optimal effect was found at the 4:1 LNA:ALA ratio where insulin-like growth factor-1 (IGF-1) and IGF binding protein-3 (IGFBP-3) production was the lowest in MC3T3-L1 cells. (b) All CLA isomer blends decreased MC3T3-L1 and increased MC3T3-E1 cell differentiation. (c) 1.5-2.5 mM calcium increased ST2 and MC3T3-E1, and decreased MC3T3-L1 cell proliferation. (d) Combination of 4:1 LNA:ALA + 90:10 % CLA + 2.0 mM calcium lowered MC3T3-L1 and increased MC3T3-E1 cell differentiation. Overall, the optimal LNA:ALA ratio to enhance osteoblastogenesis and inhibit adipogenesis was 4:1. This effect was enhanced by 90:10 % CLA + 2.0 mM calcium, indicating possible synergism of these dietary factors in promoting osteoblast and inhibiting adipocyte differentiation in cell cultures.

Long-chain polyunsaturated fatty acids may mutually benefit both obesity and osteoporosis

The overconsumption of n-6 polyunsaturated fatty acids (PUFA), resulting in a high ratio of n-6 to n-3 PUFA, may contribute to the increased pathogenesis of obesity and osteoporosis by promoting low-grade chronic inflammation (LGCI). As evidence suggests, both obesity and osteoporosis are linked on a cellular and systemic basis. This review will analyze if a relationship exists between LGCI, fat, bone, and n-3 PUFA. During the life cycle, inflammation increases, fat mass accumulates, and bone mass declines, thus suggesting that a connection exists. This review will begin by examining how the current American diet and dietary guidelines may fall short of providing an anti-inflammatory dose of the n-3 PUFA eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). It will then define LGCI and outline the evidence for a relationship between fat and bone. Inflammation as it pertains to obesity and osteoporosis and how EPA and DHA can alleviate the associated inflammation will be discussed, followed by some preliminary evidence to show how mesenchymal stem cell (MSC) lineage commitment may be altered by inflammation to favor adipogenesis. Our hypothesis is that n-3 PUFA positively influence obesity and osteoporosis by reducing LGCI, ultimately leading to a beneficial shift in MSC lineage commitment. This hypothesis essentially relates the need for more focused research in several areas such as determining age and lifestyle factors that promote the shift in MSC commitment and if current intakes of EPA and DHA are optimal for fat and bone.