FSH Level and Changes in Bone Mass and Body Composition in Older Women and Men.

Context: FSH may have independent actions on bone remodeling and body fat regulation. Cross-sectionally, we have shown that serum FSH is associated with bone mineral density (BMD) and body fat in older postmenopausal women, but it remains unknown whether FSH predicts bone and fat changes.

Objective: We examined whether baseline FSH level is associated with subsequent bone loss or body composition changes in older adults.

The Effect of Roux-en-Y Gastric Bypass on Bone Marrow Adipose Tissue and Bone Mineral Density in Postmenopausal, Nondiabetic Women.

Objectives: This study aimed to determine the effect of bariatric surgery-induced weight loss on bone marrow adipose tissue (BMAT) and bone mineral density (BMD) in postmenopausal, nondiabetic women.

Methods: A total of 14 postmenopausal, nondiabetic women with obesity who were scheduled for laparoscopic Roux-en-Y gastric bypass surgery (RYGB) were included in this study. Vertebral bone marrow fat signal fraction was determined by quantitative chemical shift magnetic resonance imaging, and vertebral volumetric BMD (vBMD) was determined by quantitative computed tomography before surgery and 3 and 12 months after surgery.

Serum FSH Is Associated With BMD, Bone Marrow Adiposity, and Body Composition in the AGES-Reykjavik Study of Older Adults.

Context: Follicle-stimulating hormone (FSH) concentrations increase during the perimenopausal transition and remain high after menopause. Loss of bone mineral density (BMD) and gain of bone marrow adiposity (BMA) and body fat mass also occur during this time. In mice, blocking the action of FSH increases bone mass and decreases fat mass.

Associations of Muscle Size and Density With Proximal Femur Bone in a Community Dwelling Older Population.

Muscle weakness and bone fragility are both associated with hip fracture. In general, muscle contractions create forces to the bone, and bone strength adapts to mechanical loading through changes in bone architecture and mass. However, the relationship between impairment of muscle and bone function remain unclear.

Muscle Density, but Not Size, Correlates Well With Muscle Strength and Physical Performance.

Objectives: There is increasing evidence that muscle volume and mass are poor predictors of muscle strength and physical performance. Other assessments of muscle quality such as skeletal muscle density measured by computed tomography (CT) may be more important. The aim of this study was to explore associations of muscle size and density with handgrip strength (HGS) and the Timed Up and Go test (TUG).

Pregnancy and lactation, a challenge for the skeleton.

In this review we discuss skeletal adaptations to the demanding situation of pregnancy and lactation. Calcium demands are increased during pregnancy and lactation, and this is effectuated by a complex series of hormonal changes. The changes in bone structure at the tissue and whole bone level observed during pregnancy and lactation appear to largely recover over time.

Reporting Guidelines, Review of Methodological Standards, and Challenges Toward Harmonization in Bone Marrow Adiposity Research. Report of the Methodologies Working Group of the International Bone Marrow Adiposity Society.

The interest in bone marrow adiposity (BMA) has increased over the last decade due to its association with, and potential role, in a range of diseases (osteoporosis, diabetes, anorexia, cancer) as well as treatments (corticosteroid, radiation, chemotherapy, thiazolidinediones). However, to advance the field of BMA research, standardization of methods is desirable to increase comparability of study outcomes and foster collaboration. Therefore, at the 2017 annual BMA meeting, the International Bone Marrow Adiposity Society (BMAS) founded a working group to evaluate methodologies in BMA research.

Ovariectomy increases RANKL protein expression in bone marrow adipocytes of C3H/HeJ mice.

Estrogen deficiency induces bone loss by increasing bone resorption, in part through upregulation of receptor activator of nuclear factor-κB ligand (RANKL). RANKL is secreted by osteoblasts and osteocytes, but more recently bone marrow (pre)adipocytes have also been shown to express RANKL. Estrogen deficiency increases bone marrow adipose tissue (BMAT).

SUGAR-DIP trial: oral medication strategy versus insulin for diabetes in pregnancy, study protocol for a multicentre, open-label, non-inferiority, randomised controlled trial.

Introduction: In women with gestational diabetes mellitus (GDM) requiring pharmacotherapy, insulin was the established first-line treatment. More recently, oral glucose lowering drugs (OGLDs) have gained popularity as a patient-friendly, less expensive and safe alternative. Monotherapy with metformin or glibenclamide (glyburide) is incorporated in several international guidelines.

The effect of PPARγ inhibition on bone marrow adipose tissue and bone in C3H/HeJ mice.

Bone marrow adipose tissue (BMAT) increases after menopause, and increased BMAT is associated with osteoporosis and prevalent vertebral fractures. Peroxisome proliferator-activated receptor-γ (PPARγ) activation promotes adipogenesis and inhibits osteoblastogenesis; therefore, PPARγ is a potential contributor to the postmenopausal increase in BMAT and decrease in bone mass. The aim of this study is to determine if PPARγ inhibition can prevent ovariectomy-induced BMAT increase and bone loss in C3H/HeJ mice.

Clinical implications of bone marrow adiposity.

Marrow adipocytes, collectively termed marrow adipose tissue (MAT), reside in the bone marrow in close contact to bone cells and haematopoietic cells. Marrow adipocytes arise from the mesenchymal stem cell and share their origin with the osteoblast. Shifts in the lineage allocation of the mesenchymal stromal cell could potentially explain the association between increased MAT and increased fracture risk in diseases such as postmenopausal osteoporosis, anorexia nervosa and diabetes.

The effect of raloxifene on bone marrow adipose tissue and bone turnover in postmenopausal women with osteoporosis.

In patients with postmenopausal osteoporosis low bone volume is associated with high bone marrow adipose tissue (MAT). Moreover, high MAT is associated with increased fracture risk. This suggests an interaction between MAT and bone turnover, however literature remains equivocal.

Mechanisms of marrow adiposity and its implications for skeletal health.

The bone marrow niche is composed of cells from hematopoietic and mesenchymal origin. Both require energy to power differentiation and these processes are intimately connected to systemic metabolic homeostasis. Glycolysis is the preferred substrate for mesenchymal stromal cells in the niche, although fatty acid oxidation and glutaminolysis are important during stage specific differentiation.

Effects of Chronic Estrogen Administration in the Ventromedial Nucleus of the Hypothalamus (VMH) on Fat and Bone Metabolism in Ovariectomized Rats.

Estrogen deficiency after ovariectomy (OVX) results in increased adiposity and bone loss, which can be prevented by systemic 17-β estradiol (E2) replacement. Studies in transgenic mice suggested that in addition to direct actions of estrogen in peripheral tissues, also estrogen signaling in the hypothalamus regulates fat distribution and bone metabolism. We hypothesized that the protective effect of systemic E2 on fat and bone metabolism in the OVX model is partly mediated through the ventromedial nucleus of the hypothalamus (VMH).

Short-Term Effect of Estrogen on Human Bone Marrow Fat.

Bone marrow fat, an unique component of the bone marrow cavity increases with aging and menopause and is inversely related to bone mass. Sex steroids may be involved in the regulation of bone marrow fat, because men have higher bone marrow fat than women and clinical observations have suggested that the variation in bone marrow fat fraction is greater in premenopausal compared to postmenopausal women and men. We hypothesized that the menstrual cycle and/or estrogen affects the bone marrow fat fraction.

Association of polymorphisms in the beta-2 adrenergic receptor gene with fracture risk and bone mineral density.

Unlabelled: Signaling through the beta-2 adrenergic receptor (B2AR) on the osteoblast influences bone remodeling in rodents. In the B2AR gene, three polymorphisms influence receptor function. We show that these polymorphisms are not associated with fracture risk or bone mineral density in the UCP, Rotterdam Study, and GEFOS cohorts.

The effects of beta-2 adrenergic agonist and antagonist on human bone metabolism: a randomized controlled trial.

Purpose: Genetic knockout or pharmacological inhibition of the beta-2 adrenergic receptor (B2AR) increased bone mass, whereas stimulation decreased bone mass in rodents. In humans, observational studies support sympathetic nervous system regulation of bone metabolism, but intervention studies are lacking. We aimed to determine the effects of a selective beta-2 adrenergic agonist and non-selective antagonist on human bone metabolism.

Bone as a regulator of glucose metabolism.

For a long time the only functions attributed to the skeleton were locomotion and calcium storage. Over the last decade, this view has changed. Genetic studies in mice have shown that bone metabolism is regulated by the autonomic nervous system and interacts with energy metabolism and reproduction.

Bone resorption is increased in pheochromocytoma patients and normalizes following adrenalectomy.

Context: The sympathetic nervous system (SNS) controls bone turnover in rodents, but it is uncertain whether a similar role for the SNS exists in humans. Pheochromocytomas are catecholamine-producing neuroendocrine tumors. Because catecholamines are the neurotransmitters of the SNS, we hypothesized that pheochromocytoma patients have increased bone turnover.