Plasminogen activator inhibitor-1 concentrations and bone mineral density in postmenopausal women with type 2 diabetes mellitus

Effects of Hyperglycemia and Diabetes Mellitus on Coagulation and Hemostasis

In patients with diabetes, metabolic disorders disturb the physiological balance of coagulation and fibrinolysis, leading to a prothrombotic state characterized by platelet hypersensitivity, coagulation disorders and hypofibrinolysis. Hyperglycemia and insulin resistance cause changes in platelet number and activation, as well as qualitative and/or quantitative modifications of coagulatory and fibrinolytic factors, resulting in the formation of fibrinolysis-resistant clots in patients with diabetes. Other coexisting factors like hypoglycemia, obesity and dyslipidemia also contribute to coagulation disorders in patients with diabetes. Management of the prothrombotic state includes antiplatelet and anticoagulation therapies for diabetes patients with either a history of cardiovascular disease or prone to a higher risk of thrombus generation, but current guidelines lack recommendations on the optimal antithrombotic treatment for these patients. Metabolic optimizations like glucose control, lipid-lowering, and weight loss also improve coagulation disorders of diabetes patients. Intriguing, glucose-lowering drugs, especially cardiovascular beneficial agents, such as glucagon-like peptide-1 receptor agonists and sodium glucose co-transporter inhibitors, have been shown to exert direct anticoagulation effects in patients with diabetes. This review focuses on the most recent progress in the development and management of diabetes related prothrombotic state.

Physical Activity Associations with Bone Mineral Density and Modification by Metabolic Traits

Objective

To assess the relationship of physical activity with bone mineral density (BMD) at various sites and examine potential modifying metabolic factors.

Methods

Responses from physical activity questionnaires were used to determine total physical activity (PA), moderate physical activity (mod-PA), and sedentary time. Regression analyses were performed to evaluate association of activity traits with insulin sensitivity by euglycemic clamp, adiponectin, C-reactive protein (CRP), and plasminogen activator inhibitor-1 (PAI-1) in 741 healthy subjects.

Results

The cohort was relatively sedentary. Activity level was associated with arm, pelvis, and leg BMD in univariate analyses. In multivariate association analyses of arm BMD, only female sex (β = -0.73, P < 0.0001) and adiponectin (β = -0.076, P = 0.0091) were significant. Multivariate analyses of pelvis BMD found independent associations with body mass index (BMI) (β = 0.33, P < 0.0001), adiponectin (β = -0.10, P = 0.013), female sex (β = -0.18, P < 0.0001), sedentary time (β = -0.088, P = 0.034), PA (β = 0.11, P = 0.01), and mod-PA (β = 0.11, P = 0.014). Age (β = -0.10, P = 0.0087), female sex (β = -0.63, P < 0.0001), BMI (β = 0.24, P < 0.0001), and mod-PA (β = 0.10, P = 0.0024) were independently associated with leg BMD.

Conclusions

These results suggest that BMD increases with physical activity in the arms, legs, and pelvis and is inversely related to sedentary time in the pelvis and legs; these associations may be modified by age, sex, BMI, and adiponectin, depending on the site, with physical activity being more important to pelvis and leg BMD than arm BMD and sedentary time being important for pelvis BMD. Moreover, we demonstrated that CRP, PAI-1, and insulin sensitivity play a minor role in BMD.

Effect of GSK-137647A, the first non-carboxylic FFA4 agonist, on the osteogenic and adipogenic differentiation of bone mesenchymal stem cells in db/db mice

OBJECTIVE

To investigate the effect of GSK-137647A, the first non-carboxylic FFA4 agonist, on osteogenic and adipogenic differentiation of bone mesenchymal stem cells (BMSCs) of db/db mice.

METHODS

Bone mesenchymal stem cells were extracted from 8-week-old db/db mice. Cell Counting Kit-8 was used to evaluate the toxicity of GSK-137647A on BMSCs, and the optimal concentration of GSK-137647A was selected to investigate the osteogenic and adipogenic differentiation of BMSCs, and relevant indicators of osteoblasts and adipocytes were detected.

KEY FINDINGS

GSK-137647A had no significant toxicity on cell growth and proliferation. Moreover, GSK-137647A showed a significant increase in mineralization of BMSCs differentiated osteoblasts compared to the control group and elevated the alkaline phosphatase (ALP) activity in a time-dependent manner. Meanwhile, the treatment of GSK-137647A decreased the adipogenic differentiation of BMSCs. The expression levels of ALP, runt-related transcription factor 2, bone morphogenetic protein 4, osterix and β-catenin were significantly increased in GSK-137647A-treated group, while the gene and protein levels of peroxisome proliferator-activated receptor γ and CCAAT/enhancer binding protein α were significantly reduced.

CONCLUSIONS

All of these results demonstrated that GSK-137647A suppressed the adipogenic differentiation and promoted osteogenic differentiation of BMSCs, which is partly attributed to the increased expression of β-catenin in wingless/integrated signalling pathway.

An update on therapies for the treatment of diabetes-induced osteoporosis

Introduction: Currently, 424 million people aged between 20 and 79 years worldwide are diabetic. More than 25% of adults aged over 65 years in North America have Type 2 diabetes mellitus (DM). Diabetes-induced osteoporosis (DM-OS) is caused by chronic hyperglycemia, advanced glycated end products and oxidative stress. The increase in the prevalence of DM-OS has prompted researchers to develop new biological therapies for the management of DM-OS. Areas covered: This review covered the current and novel biological agents used in the management of DM-OS. Data were retrieved from PubMed, Scopus, American Diabetes Association and International Osteoporosis Foundation websites, and ClinicalTrials.gov. The keywords for the search included: DM, osteoporosis, and management. Expert opinion: Several biological molecules have been examined in order to find efficient drugs for the treatment of DM-OS. These biological agents include anti-osteoporosis drugs: net anabolics (parathyroid hormone/analogs, androgens, calcilytics, anti-sclerostin antibody), net anti-resorptive osteoporosis drugs (calcitonin, estrogen, selective estrogen receptor modulators, bisphosphonates, RANKL antibody) and anti-diabetic drugs (alpha glucosidase inhibitors, sulfonylureas, biguanides, meglitinides, thiazolidinediones, GLP-1 receptor agonists, dipeptidylpeptidase-4 inhibitors, sodium glucose co-transporter-2 inhibitors, insulin). Biological medications that effectively decrease hyperglycemia and, at the same time, maintain bone health would be an ideal drug/drug combination for the treatment of DM-OS.

Genistein treatment improves fracture resistance in obese diabetic mice

BACKGROUND

Obese, type two diabetics are at an increased risk for fracturing their limb bones in comparison to the general population. Phytoestrogens like as the soy isoflavone genistein have been shown to protect against bone loss. In this study, we tested the effects of genistein treatment on femurs of ob/ob mice, a model for obesity and type two diabetes mellitus.

METHODS

Twenty six-week-old female mice were divided into obese (ob/ob) control, obese genistein-treated, lean (ob/+) control, and lean genistein-treated groups (n = 5 each). Treatment with genistein consisted of 600 mg genistein/kg diet. Control mice were given standard rodent chow. At the end of a four-week treatment period, bone histomorphometric and three-point bending properties were compared among groups.

RESULTS

Obese mice had larger bone areas (B.Ar.; P < 0.05) and total areas (Tt.Ar.; P < 0.05), but similar bone volume (B.Ar./Tt.Ar.; P > 0.05) of the proximal femoral epiphysis in comparison to lean mice. Treatment with genistein decreased Tt.Ar. and femur length, and increased ultimate force required to fracture the femur and the maximum deformation to failure (P < 0.05).

CONCLUSIONS

Genistein improves resistance to fracture from bending loads.