Relationship Between Metabolic Syndrome and Bone Health - An Evaluation of Epidemiological Studies and Mechanisms Involved

Skeletal Effects of a Prolonged Oral Metformin Treatment in Adult Wistar Rats

INTRODUCTION

We previously showed that a 3-week oral metformin (MET) treatment enhances the osteogenic potential of bone marrow stromal cells (BMSCs) and improves several bone histomorphometric parameters in Wistar rats with metabolic syndrome (MetS). However, the skeletal effects of extended periods of MET need to be completely elucidated. Hence, in this study, the impact of a prolonged (3-month) MET treatment was investigated on bone architecture, histomorphometric and biomechanics variables, and osteogenic potential of BMSCs in Wistar rats with or without MetS.

MATERIALS AND METHODS

Young male Wistar rats (n=36) were randomized into four groups (n=9) that received either 20% fructose (F), MET (MET), F plus MET treatments (FMET), or drinking water alone (Veh). Rats were euthanized, blood was collected, and bones were dissected and processed for peripheral quantitative computed tomography (pQCT) analysis, static and dynamic histomorphometry, and bone biomechanics. In addition, BMSCs were isolated to determine their osteogenic potential.

RESULTS

MET affected trabecular and cortical bone, altering bone architecture and biomechanics. Furthermore, MET increased the pro-resorptive profile of BMSCs. In addition, fructose-induced MetS practically did not affect the the structural or mechanical variables of the skeleton.

CONCLUSION

A 3-month treatment with MET (with or without MetS) affects bone architecture and biomechanical variables in Wistar rats.

Single high-dose intravenous injection of Wharton's jelly-derived mesenchymal stem cell exerts protective effects in a rat model of metabolic syndrome

BACKGROUND

Metabolic syndrome (MetS) is a significant epidemiological problem worldwide. It is a pre-morbid, chronic and low-grade inflammatory disorder that precedes many chronic diseases. Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) could be used to treat MetS because they express high regenerative capacity, strong immunomodulatory properties and allogeneic biocompatibility. This study aims to investigate WJ-MSCs as a therapy against MetS in a rat model.

METHODS

Twenty-four animals were fed with high-fat high-fructose (HFHF) diet ad libitum. After 16 weeks, the animals were randomised into treatment groups (n = 8/group) and received a single intravenous administration of vehicle, that is, 3 × 106 cells/kg or 10 × 106 cells/kg of WJ-MSCs. A healthy animal group (n = 6) fed with a normal diet received the same vehicle as the control (CTRL). All animals were periodically assessed (every 4 weeks) for physical measurements, serum biochemistry, glucose tolerance test, cardiovascular function test and whole-body composition. Post-euthanasia, organs were weighed and processed for histopathology. Serum was collected for C-reactive protein and inflammatory cytokine assay.

RESULTS

The results between HFHF-treated groups and healthy or HFHF-CTRL did not achieve statistical significance (α = 0.05). The effects of WJ-MSCs were masked by the manifestation of different disease subclusters and continuous supplementation of HFHF diet. Based on secondary analysis, WJ-MSCs had major implications in improving cardiopulmonary morbidities. The lungs, liver and heart show significantly better histopathology in the WJ-MSC-treated groups than in the untreated CTRL group. The cells produced a dose-dependent effect (high dose lasted until week 8) in preventing further metabolic decay in MetS animals.

CONCLUSIONS

The establishment of safety and therapeutic proof-of-concept encourages further studies by improving the current therapeutic model.

Nutraceuticals and Functional Foods: A Comprehensive Review of Their Role in Bone Health

Bone health is the result of a tightly regulated balance between bone modeling and bone remodeling, and alterations of these processes have been observed in several diseases both in adult and pediatric populations. The imbalance in bone remodeling can ultimately lead to osteoporosis, which is most often associated with aging, but contributing factors can already act during the developmental age, when over a third of bone mass is accumulated. The maintenance of an adequate bone mass is influenced by genetic and environmental factors, such as physical activity and diet, and particularly by an adequate intake of calcium and vitamin D. In addition, it has been claimed that the integration of specific nutraceuticals such as resveratrol, anthocyanins, isoflavones, lycopene, curcumin, lutein, and β-carotene and the intake of bioactive compounds from the diet such as honey, tea, dried plums, blueberry, and olive oil can be efficient strategies for bone loss prevention. Nutraceuticals and functional foods are largely used to provide medical or health benefits, but there is an urge to determine which products have adequate clinical evidence and a strong safety profile. The aim of this review is to explore the scientific and clinical evidence of the positive role of nutraceuticals and functional food in bone health, focusing both on molecular mechanisms and on real-world studies.

Metformin treatment prevents experimental metabolic syndrome-induced femoral bone marrow adiposity in rats

OBJECTIVE.

Motivation for the study. Most research supports a negative association between metabolic syndrome and bone health, although there is an overall lack of consensus. Therefore, there is a need for research in this area to develop a better understanding. Main findings. Metabolic syndrome induced by a fructose-rich diet increases the adipogenic predisposition of bone marrow progenitor cells and femoral medullary adiposity in rats. Furthermore, this can be partially prevented by co-treatment with metformin. Implications. Experimental metabolic syndrome has negative effects on bone tissue and can be prevented by oral treatment with metformin as a normoglycemic drug. To determine the effect of metformin (MET) treatment on adipogenic predisposition of bone marrow progenitor cells (BMPC), bone marrow adiposity and bone biomechanical properties.

MATERIALS AND METHODS.

20 young adult male Wistar rats were sorted into four groups. Each of the groups received the following in drinking water: 100% water (C); 20% fructose (F); metformin 100 mg/kg wt/day (M); or fructose plus metformin (FM). After five weeks the animals were sacrificed. Both humeri were dissected to obtain BMPC, and both femurs were dissected to evaluate medullary adiposity (histomorphometry) and biomechanical properties (3-point bending). BMPC were cultured in vitro in adipogenic medium to evaluate RUNX2, PPAR-γ and RAGE expression by RT-PCR, lipase activity and triglyceride accumulation.

RESULTS.

The fructose-rich diet (group F) caused an increase in both triglycerides in vitro, and medullary adiposity in vivo; being partially or totally prevented by co-treatment with metformin (group FM). No differences were found in femoral biomechanical tests in vivo, nor in lipase activity and RUNX2/PPAR-γ ratio in vitro. DRF increased RAGE expression in BMPC, being prevented by co-treatment with MET.

CONCLUSIONS.

Metabolic syndrome induced by a fructose-rich diet increases femoral medullary adiposity and, in part, the adipogenic predisposition of BMPC. In turn, this can be totally or partially prevented by oral co-treatment with MET.

Relative Contribution of Metabolic Syndrome Components in Relation to Obesity and Insulin Resistance in Postmenopausal Osteoporosis

Introduction. Osteoporosis (OP) affects 30% of postmenopausal women, often complicated by metabolic syndrome (MetS) with a still controversial role. We aimed to characterize MetS and its components in relation to bone mineral density (BMD), body mass index (BMI), and insulin resistance. Methods. Patients (n = 188) underwent DEXA scans, spine X-rays, and metabolic and hormonal investigations, including bone biomarkers, muscular strength, and physical performance tests, while insulin resistance was evaluated by the Homeostasis Model Assessment (HOMA-IR). Results. Patients with a normal BMD or osteopenia (n = 68) and with OP (n = 120) displayed 51.5% and 30.8% of MetS, but without differences in insulin resistance. When BMD was studied as a function of the cumulative MetS criteria and centiles of BMI, lower levels of BMD were observed beyond an inflection point of 27.2 kg/m2 for BMI, allowing for further stratification as lean and overweight/obese (OW/OB) subjects. In contrast with lean individuals (n = 74), in OW/OB patients (n = 46), MetS was associated with HbA1c (p < 0.0037, OR 9.6, 95% CI [1.64-55.6]) and insulin resistance (p < 0.0076, OR 6.7, 95% CI [1.49-30.8]) in the context where BMD values were lower than those predicted from BMI in non-OP subjects. In OP patients with fragility fractures (31% of MetS), glycemia also appeared to be the dominant factor for MetS (p < 0.0005, OR 4.1, 95% CI [1.63-10.39]). Conclusions. These data indicate a detrimental effect of insulin resistance in MetS on OP patients, while the prevalence of the syndrome depends on the proportion of obesity. These findings provide new insights into the pathogenic role of MetS and reveal the need to consider different strata of BMI and insulin resistance when studying postmenopausal OP.

Combined Effect of Dietary Acid Load and Cardiometabolic Syndrome on Bone Resorption Marker among Post-Menopausal Women in Malaysia

Background

This study aimed to investigate factors associated with bone resorption status and determine the independent and interactive effects of dietary acid load (DAL) and cardiometabolic syndrome (CMS) on bone resorption in post-menopausal women.

Methods

Overall, 211 community-dwelling post-menopausal women were recruited from the National Council of Senior Citizens Organization, Malaysia. DAL was estimated using the potential renal acid load from the food frequency questionnaire. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI) and smoking behaviour was assessed using the Global Adult Tobacco Survey 2011. Serum 25(OH) vitamin D levels were determined using the ADVIA Centaur vitamin D assay and serum C-terminal telopeptides of type I collagen (CTX1) were used as surrogate markers to assess bone resorption. CMS was determined based on the harmonised criteria.

Results

Age (β = -0.145, t = -2.002, P < 0.05) was negatively associated while DAL (β = 0.142, t = 2.096, P < 0.05) and sleep quality (β = 0.147, t = 2.162, P < 0.05) were positively associated with CTX1. Height was positively correlated with CTX1 (r = 0.136, P <0.05). Conversely, other variables (CMS traits, CMS, serum 25(OH) vitamin D level, years of menopause, years of education and physical activity) were not significantly associated with CTX1 levels. There was no significant interaction between DAL and CMS on bone resorption.

Conclusion

Our findings propose that high DAL, but not CMS, is a potential risk factor for bone resorption. The analysis did not demonstrate the combined effects of DAL and CMS on bone resorption.

Impact of metabolic syndrome on bone mineral density in men over 50 and postmenopausal women according to U.S. survey results

Metabolic Syndrome (MetS) and bone mineral density (BMD) have shown a controversial link in some studies. This research aims to study their association in males over 50 and postmenopausal females using National Health and Nutrition Examination Survey (NHANES) data. Postmenopausal females and males over 50 were included in the study. MetS was defined by the National Cholesterol Education Program Adult Treatment Panel III guidelines. BMD values were measured at the thoracic spine, lumbar spine, and pelvis as the primary outcome. Weighted multivariate general linear models have been employed to explore the status of BMD in patients with MetS. Additionally, interaction tests and subgroup analyses were conducted. Utilizing the NHANES database from 2003 to 2006 and 2011-2018, we included 1924 participants, with 1029 males and 895 females. In postmenopausal women, after adjusting for covariates, we found a positive correlation between MetS and pelvic (β: 0.030 [95%CI 0.003, 0.06]) and thoracic (β: 0.030 [95%CI 0.01, 0.06]) BMD, though not for lumbar spine BMD (β: 0.020 [95%CI - 0.01, 0.05]). In males over 50 years old, MetS was positively correlated with BMD in both Model 1 (without adjusting for covariates) and Model 2 (considering age and ethnicity). Specifically, Model 2 revealed a positive correlation between MetS and BMD at the pelvis (β: 0.046 [95%CI 0.02, 0.07]), thoracic spine (β: 0.047 [95%CI 0.02, 0.07]), and lumbar spine (β: 0.040 [95%CI 0.02, 0.06]). Subgroup analysis demonstrated that the relationship between MetS and BMD remained consistent in all strata, underscoring the stability of the findings. In postmenopausal women, after adjusting for all covariates, a significant positive correlation was observed between MetS and BMD in the pelvis and thoracic spine, whereas this correlation was not significant for lumbar spine BMD. Conversely, in males, positive correlations between MetS and BMD at the lumbar spine, thoracic spine, and pelvis were identified in Model 2, which adjusted for age and ethnicity; however, these correlations disappeared after fully adjusting for all covariates. These findings highlight the potential moderating role of gender in the impact of MetS on BMD.

ROS/MMP-9 mediated CS degradation in BMSC inhibits citric acid metabolism participating in the dual regulation of bone remodelling

It is necessary to figure out the abnormal energy metabolites at the cellular level of postmenopausal osteoporosis (PMOP) bone microenvironment. In this study, we constructed PMOP model by ovariectomy and identified 9 differential metabolites compared with control femur by energy metabolomic. The enrichment analysis of differential metabolites revealed that tricarboxylic acid cycle, glucagon pathway and purinergic signaling pathway were the main abnormal metabolic processes. Citric acid was identified as the key metabolite by constructing compound reaction-enzyme-gene network. The functional annotation of citric acid targets identified by network pharmacological tools indicated that matrix metalloproteinase 9 (MMP-9) may be involved in regulating citric acid metabolism in the osteogenic differentiation of bone marrow mesenchymal stem cell (BMSC). Molecular docking shows that the interaction forces between MMP-9 and citric acid synthase (CS) is -638, and there are multiple groups of residues used to form hydrogen bonds. Exogenous H2O2 promotes the expression of MMP-9 in BMSC to further degrade CS resulting in a decrease in mitochondrial citric acid synthesis, which leads to the disorder of bone remodeling by two underlying mechanisms ((1) the decreased histone acetylation inhibits the osteogenic differentiation potential of BMSC; (2) the decreased bone mineralization by citric acid deposition). MMP-9-specific inhibitor (MMP-9-IN-1) could significantly improve the amount of CS in BMSC to promote cellular citric acid synthesis, and further enhance bone remodeling. These findings suggest inhibiting the degradation of CS by MMP-9 to promote the net production of citric acid in osteogenic differentiation of BMSC may be a new direction of PMOP research.

Metabolic Syndrome Increases Risk of Readmission and Complications in Operative Fixation of Pilon Fractures

Background Studies demonstrate that metabolic syndrome (MetS) negatively impacts surgical outcomes. This study sought to identify how metabolic syndrome affects outcomes after open reduction and internal fixation (ORIF) of traumatic pilon fractures. Methods Patients who underwent ORIF for pilon fractures from 2012 to 2019 were identified in the American College of Surgeons National Surgical Quality Improvement Program database. Patients with MetS were compared to non-MetS patients for rates of adverse events, prolonged stay, readmission, discharge location, and operative time in the 30-day postoperative period. All statistical analyses were conducted using SPSS version 26.0 (IBM Corp., Armonk, NY, USA). Paired student t-tests were used to assess continuous variables. Pearson's Chi-square and odds ratios were used for categorical variables. Results A total of 1,915 patients met this study's inclusion criteria, and 127 MetS patients were identified in the cohort. The MetS cohort was older (62.7 vs 49.5 years old, p-value <0.01), with a greater proportion of female patients (59.1% vs 50.2%, p=0.054). MetS patients experienced significantly higher rates of infectious complications (7.9% vs 3.9% OR 2.75 (CI 1.36-5.53), p=0.008), major adverse events (11% vs 4.3%, OR 2.79 (CI 1.53-5.09) p=0.002), and readmissions. MetS patients also had longer lengths of stay (7 days vs 3.8 days, p-value<0.001), and were more likely to be discharged to a non-home location (51.2% vs 19.5%, p-value<0.01, OR 4.32 (CI=3.0-6.24) p<0.001). Conclusion Patients with MetS have an increased risk of 30-day major complications, infection, readmissions, discharge to a non-home location, and prolonged operative time, and therefore warrant additional consideration for perioperative monitoring.

INSULIN RESISTANCE AND PATHOGENESIS OF POSTMENOPAUSAL OSTEOPOROSIS

Osteoporosis (OP) is a disease predisposing postmenopausal women to fractures, and often accompanied by insulin resistance (IR) and metabolic syndrome (MetS). Previous studies provided contradictory results concerning prevalence of MetS in postmenopausal OP. To better understand the pathogenesis of IR, we reviewed cellular and molecular aspects and systematically reviewed studies providing homeostasis model assessment (HOMA) index. Bone is an active endocrine organ maintaining its integrity by orchestrated balance between bone formation and resorption. Both osteoblasts and osteoclasts contain receptors for insulin and insulin-like growth factor-1 (IGF-1) operating in skeletal development and in the adult life. Defects in this system generate systemic IR and bone-specific IR, which in turn regulates glucose homeostasis and energy metabolism through osteocalcin. Examination of genetic syndromes of extreme IR revealed intriguing features namely high bone mineral density (BMD) or accelerated growth. Studies of moderate forms of IR in postmenopausal women reveal positive correlations between HOMA index and BMD while correlations with osteocalcin were rather negative. The relation with obesity remains complex involving regulatory factors such as leptin and adiponectin to which the contribution of potential genetic factors and in particular, the correlation with the degree of obesity or body composition should be added.

The association between weight-adjusted-waist index and total bone mineral density in adolescents: NHANES 2011-2018

Introduction

The weight-adjusted waist index (WWI) serves as an innovative obesity measure, seemingly surpassing body mass index (BMI) and waist circumference (WC) in evaluating lean and fat mass. This study aimed to explore the relationship between WWI and total bone mineral density (BMD) in US adolescents.

Methods

This population-based study investigated adolescents aged 8-19 years with comprehensive WWI and total BMD data from the National Health and Nutrition Examination Survey (NHANES) 2011-2018. WWI was computed by dividing WC by the square root of body weight. Weighted multivariate linear regression and smoothed curve fitting were employed to examine linear and non-linear associations. Threshold effects were determined using a two-part linear regression model. Additionally, subgroup analyses and interaction tests were conducted.

Results

Multivariate linear regression analysis revealed a significant negative association between WWI and total BMD in 6,923 US adolescents aged 8-19 years [β = -0.03, 95% CI: (-0.03, -0.03)]. This negative correlation remained consistent across all subcategories, with the exception of age, encompassing gender,ethnicity, and diabetes status subgroups. Furthermore, a non-linear relationship and saturation effect between WWI and total BMD were identified, with an inflection point at 9.88 cm/√kg.

Conclusions

Our research demonstrated a notable negative relationship and saturation effect between WWI and total BMD among US adolescents.

Non-Alcoholic Fatty Liver Disease and Bone Tissue Metabolism: Current Findings and Future Perspectives

Non-alcoholic fatty liver disease (NAFLD) is reaching epidemic proportions worldwide. Moreover, the prevalence of this liver disease is expected to increase rapidly in the near future, aligning with the rise in obesity and the aging of the population. The pathogenesis of NAFLD is considered to be complex and to include the interaction between genetic, metabolic, inflammatory, and environmental factors. It is now well documented that NAFLD is linked to the other conditions common to insulin resistance, such as abnormal lipid levels, metabolic syndrome, and type 2 diabetes mellitus. Additionally, it is considered that the insulin resistance may be one of the main mechanisms determining the disturbances in both bone tissue metabolism and skeletal muscles quality and functions in patients with NAFLD. To date, the association between NAFLD and osteoporosis has been described in several studies, though it worth noting that most of them included postmenopausal women or elderly patients and originated from Asia. However, taking into account the health and economic burdens of NAFLD, and the increasing prevalence of obesity in children and adolescents worldwide, further investigation of the relationship between osteopenia, osteoporosis and sarcopenia in NAFLD, including in young and middle-aged patients, is of great importance. In addition, this will help to justify active screening and surveillance of osteopenia and osteoporosis in patients with NAFLD. In this review, we will discuss various pathophysiological mechanisms and possible biologically active molecules that may interplay between NAFLD and bone tissue metabolism.

Honey: A Promising Therapeutic Supplement for the Prevention and Management of Osteoporosis and Breast Cancer

Osteoporosis and breast cancer are serious diseases that have become a significant socioeconomic burden. There are biochemical associations between the two disorders in terms of the amended function of estrogen, receptor activator of nuclear factor kappa beta ligand, oxidative stress, inflammation, and lipid accumulation. Honey as a functional food with high antioxidant and anti-inflammatory properties can contribute to the prevention of various diseases. Its health benefits are mainly related to the content of polyphenols. This review aims to summarize the current knowledge from in vitro, animal, and human studies on the use of honey as a potential therapeutic agent for osteoporosis and breast cancer. Preclinical studies have revealed a beneficial impact of honey on both bone health (microstructure, strength, oxidative stress) and breast tissue health (breast cancer cell proliferation and apoptosis, tumor growth rate, and volume). The limited number of clinical trials, especially in osteoporosis, indicates the need for further research to evaluate the potential benefits of honey in the treatment. Clinical studies related to breast cancer have revealed that honey is effective in increasing blood cell counts, interleukin-3 levels, and quality of life. In summary, honey may serve as a prospective therapeutic supplement for bone and breast tissue health.

Relationship between the High Fatty Liver Index and Risk of Fracture

Background/Aims

The prevalence of nonalcoholic fatty liver disease (NAFLD) has increased rapidly as a consequence of more sedentary lifestyles and a Westernized diet. Fracture is a major clinical problem in older people, but few large-scale cohort studies have evaluated the relationship between NAFLD and fracture. Therefore, we aimed to determine whether the fatty liver index (FLI), which represents the severity of NAFLD, can predict fracture risk.

Methods

We analyzed the relationship between the FLI and incident fracture using multivariate Cox proportional hazards models and data for 180,519 individuals who underwent National Health check-ups in the Republic of Korea between 2009 and 2014.

Results

A total of 2,720 participants (1.5%) were newly diagnosed with fracture during the study period (median 4.6 years). The participants were grouped according to FLI quartiles (Q1, 0 to <5.653; Q2, 5.653 to <15.245; Q3, 15.245 to <37.199; and Q4 ≥37.199). The cumulative fracture incidence was significantly higher in the highest FLI group than in the lowest FLI group (Q4, 986 [2.2%] and Q1, 323 [0.7%]; p<0.001). The adjusted hazard ratio indicated that the highest FLI group was independently associated with a higher incidence of fracture (hazard ratio for Q4 vs Q1, 2.956; 95% confidence interval, 2.606 to 3.351; p<0.001). FLI was significantly associated with a higher incidence of fracture, independent of the baseline characteristics of the participants.

Conclusions

Our data imply that the higher the FLI of a Korean patient is, the higher their risk of osteoporotic fracture, independent of key confounding factors. (Gut Liver, Published online July 27, 2022).

Precedence of Bone Loss Accompanied with Changes in Body Composition and Body Fat Distribution in Patients with Type 2 Diabetes Mellitus

Methods

A total of 596 patients with T2DM, including 308 male and 288 female patients, were included in the follow-up study; the median follow-up time was 2.17 years. We calculated the difference between the endpoint and the baseline of each body composition index and the annual rate. The research participants were divided into the increased body mass index (BMI) group, stable BMI group, and decreased BMI group. Some confounding factors were adjusted, such as BMI, fat mass index (FMI), muscle mass index (MMI), muscle/fat mass ratio (M/F), trunk fat mass index (TFMI), appendicular skeletal muscle mass index (ASMI), and appendicular skeletal muscle mass/trunk fat mass ratio (A/T).

Results

The linear analysis showed that ΔFMI and ΔTFMI were negatively correlated with the change in femoral neck BMD (ΔFNBMD) and ΔMMI, ΔASMI, ΔM/F, and ΔA/T were positively correlated with ΔFNBMD. The risk of FNBMD reduction in patients with increased BMI was 56.0% lower than that in patients with decreased BMI; also, the risk in patients with stable M/F was 57.7% lower than that in patients with decreased M/F. The risk in the A/T increase group was 62.9% lower than that in the A/T decrease group.

Conclusions

A reasonable muscle/fat ratio is still beneficial to maintaining bone mass. Maintaining a certain BMI value is conducive to maintaining FNBMD. Simultaneously, increasing the proportion of muscle mass and reducing fat accumulation can also prevent FNBMD loss.

A Mini Review on Osteoporosis: From Biology to Pharmacological Management of Bone Loss

Osteoporosis refers to excessive bone loss as reflected by the deterioration of bone mass and microarchitecture, which compromises bone strength. It is a complex multifactorial endocrine disease. Its pathogenesis relies on the presence of several endogenous and exogenous risk factors, which skew the physiological bone remodelling to a more catabolic process that results in net bone loss. This review aims to provide an overview of osteoporosis from its biology, epidemiology and clinical aspects (detection and pharmacological management). The review will serve as an updated reference for readers to understand the basics of osteoporosis and take action to prevent and manage this disease.

Association between metabolic syndrome and osteoporosis among adults aged 50 years and older: using the National Health Information Database in South Korea

This study aimed to examine the association between a history of metabolic syndrome (MetS) and osteoporosis with specific characteristics. The results showed that MetS was inversely associated with osteoporosis. In contrast, MetS was positively associated with osteoporosis in both obese men and postmenopausal obese women.

PURPOSE

Although several previous studies have investigated the association between MetS and osteoporosis, their findings remain controversial. This study aimed to examine the association between a MetS history and osteoporosis using a subset of data from a large, long-term, national database.

METHODS

This nested case-control study used the National Health Information Database (NHID) of the Korea National Health Insurance Service (NHIS) from 2009 to 2017. Osteoporosis (n = 459,771) and control (n = 459,771) participants were matched in a 1:1 ratio by age, gender, income, and region of residence. MetS was defined based on the modified National Cholesterol Education Program-Adult Treatment Panel III criteria. Crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) for osteoporosis in patients with MetS and its components were analyzed using logistic regression. Subgroup analyses were performed according to the combination of gender, menopausal status, and obesity status.

RESULTS

The adjusted OR (95% CI) for osteoporosis in patients with MetS was 0.95 (0.94-0.96). This finding was consistent with the subgroup analyses in normal weight men, premenopausal (pre-MP) women with all obesity statuses, and postmenopausal (post-MP) underweight and normal weight women. In contrast, the opposite was observed for obese men (OR = 1.05, 95% CI = 1.01-1.09) and post-MP obese women (OR = 1.05, 95% CI = 1.01-1.08).

CONCLUSION

This study results suggested that MetS was associated with a low occurrence of osteoporosis. In contrast, MetS was associated with a high occurrence of osteoporosis in both obese men and post-MP obese women.

The Anthropometric Measure 'A Body Shape Index' May Predict the Risk of Osteoporosis in Middle-Aged and Older Korean People

A body shape index (ABSI) is a recently introduced index of abdominal adiposity, relative to body mass index and height, and represents an alternative to body mass index and waist circumference. We aimed to determine whether ABSI is associated with osteoporosis and the ability of ABSI to predict osteoporosis, to investigate the relationship between obesity and osteoporosis In total, 6717 Korean participants (3151 men and 3566 women; 63.6 ± 8.5 years) were recruited and placed into the Normal, Osteopenia, or Osteoporosis groups on the basis of the minimum T-scores of the lumbar spine, proximal femur, and femoral neck. The T-scores of each region and ABSI were compared among the groups and odds ratios and cut-off values of ABSI for osteoporosis were calculated. In participants of both sexes, ABSI tended to increase as bone health deteriorated. The men and women in the highest quartile of ABSI were 1.887 and 2.808 times more likely to have osteoporosis, respectively, and the potential ABSI cut-off values for osteoporosis were 0.0813 and 0.0874 for male and female participants, respectively. These findings suggest that augmentation of ABSI and obesity is associated with a higher risk of osteoporosis and that ABSI may predict the risk of osteoporosis.

Association of different lipid measures with incident bone fractures: Tehran Lipid and Glucose Study

OBJECTIVE

to investigate the association between different lipid measures and long-term hospitalization-required incident fracture among Iranian men and women.

METHODS

A total of 3309 individuals aged ≥50 years (men = 1598) were included in the study. Multivariate Cox proportional hazard analyses were performed to assess the risk of incident fracture across quintiles, considering first quintile as reference, as well as for 1-standard deviation (SD) increase in each lipid measures i.e. total cholesterol (TC), triglycerides (TG), low and high density lipoprotein cholesterol (LDL-C and HDL-C, respectively), non-HDL-C, and related indices (TG/HDL-C and TC/HDL-C). Covariates included age, body mass index, current smoking, type 2 diabetes mellitus, hypertension, lipid lowering-drugs, and steroid medications (for women).

RESULTS

During a median follow-up of 18 years, incident fracture was observed in 201 cases (men=87). In both gender no linear association were found between different lipid measures and incident fracture. Among men only the fourth quartile of TG was associated with lower risk of fracture in the age adjusted analysis with hazard ratio (HR) and 95% confidence interval (CI) as [0.45 (0.21-0.95)]. Among women, the age-adjusted HRs and 95% CIs for the second, third, fourth and fifth quintiles of non-HDL-C were [0.46 (0.25-0.87)], [0.73 (0.42-1.25)], [0.90 (0.54-1.51)], [0.52 (0.29-0.95)], respectively; the corresponding values in the multivariate model, were [[0.48 (0.26-0.90)], [0.76 (0.4-1.32)], [0.94 (0.56-1.58)], and [0.52 (0.28-0.95)], respectively. The second quintile of LDL-C was also associated with lower risk for incident fracture in the multivariate analysis [0.53 (0.29-0.98)].

CONCLUSIONS

Among Iranian women a nonlinear association between non-HDL-C and LDL-C and incident fracture were found as the second and fifth quintile of the former and the second quintile of the latter were associated with about 50% lower risk of fracture .Generally our findings did not support harmful impact of these lipid measures on incident fracture.

The Role of Fibroblast Growth Factor 19 Subfamily in Different Populations Suffering From Osteoporosis

Fibroblast growth factor (FGF) 19 subfamily, also known as endocrine fibroblast growth factors (FGFs), is a newly discovered metabolic regulator, including FGF19, FGF21 and FGF23. They play significant roles in maintaining systemic homeostasis, regulating the balance of bile acid and glucolipid metabolism in humans. Osteoporosis is a chronic disease, especially in the current status of aging population, osteoporosis is the most prominent chronic bone disease, leading to multiple complications and a significant economic burden that requires long-term or even lifelong management. Members of the FGF family have been shown to be associated with bone mineral density (BMD), fracture repair and cartilage regeneration. Studies of the FGF19 subfamily in different populations with osteoporosis have been increasing in recent years. This review summarizes the role of the FGF19 subfamily in bone metabolism, and provides new options for the treatment of bone diseases such as osteoporosis.

Obesity and Bone: A Complex Relationship

There is a large literature on the relationship between obesity and bone. What we can conclude from this review is that the increase in body weight causes an increase in BMD, both for a mechanical effect and for the greater amount of estrogens present in the adipose tissue. Nevertheless, despite an apparent strengthening of the bone witnessed by the increased BMD, the risk of fracture is higher. The greater risk of fracture in the obese subject is due to various factors, which are carefully analyzed by the Authors. These factors can be divided into metabolic factors and increased risk of falls. Fractures have an atypical distribution in the obese, with a lower incidence of typical osteoporotic fractures, such as those of hip, spine and wrist, and an increase in fractures of the ankle, upper leg, and humerus. In children, the distribution is different, but it is not the same in obese and normal-weight children. Specifically, the fractures of the lower limb are much more frequent in obese children. Sarcopenic obesity plays an important role. The authors also review the available literature regarding the effects of high-fat diet, weight loss and bariatric surgery.

Effects of Itxasol© Components on Gene Expression in Bacteria Related to Infections of the Urinary Tract and to the Inflammation Process

Urinary tract infections (UTIs) represent a health problem of the first magnitude since they affect large segments of the population, cause increased mortality and comorbidity, and have a high incidence of relapse. Therefore, UTIs cause a major socioeconomic concern. Current antibiotic treatments have various limitations such as the appearance of resistance to antibiotics, nephrotoxicity, and side effects such as gastrointestinal problems including microbiota alterations that contribute to increasing antibiotic resistance. In this context, Itxasol© has emerged, approved as an adjuvant for the treatment of UTIs. Designed with biomimetic principles, it is composed of arbutin, umbelliferon, and N-acetyl cysteine. In this work, we review the activities of these three compounds concerning the changes they produce in the expression of bacterial genes and those related to inflammation as well as assess how they are capable of affecting the DNA of bacteria and fungi.

Osteoporosis guideline awareness among Iranian nurses: results of a knowledge and attitudes survey

Introduction

Osteoporosis is a chronic and progressive disease associated with gradual bone loss and elevated risk of fracture. Role of health care professional especially nurses in lowering burden of osteoporosis via patients and public education is critical. Current study conducted to evaluate knowledge and attitude regarding osteoporosis among the nurses in orthopedic wards and their experience with national clinical osteoporosis guideline.

Methods

A cross-sectional study was conducted from August to December 2016 among all nurses in orthopedic ward of hospitals affiliated to Shiraz University of Medical Sciences. The 23- item self-administered scale consisted of knowledge and attitude questions were used. Moreover, data regarding participation in osteoporosis training courses and awareness of the national osteoporosis clinical guideline were collected as a measure of nurses’ experience with guideline. The gathered data were analyzed using SPSS (V. 16), student t-test was used to compare total knowledge and attitude scores between categorical demographic and professional data. Pearson test was used to calculate the correlation between total knowledge and attitude scores and years of practice. A p-value < 0.05 was considered statistically significant.

Results

From total of 160 nurses, 143 of them completed the questionnaire (response rate: 89.3%). The total mean ± SD knowledge and attitude scores were 11.60 ± 3.10 and 3.47 ± 0.92 respectively. Six nurses (4.2%) had participated in osteoporosis training courses after graduation, and 39 (27.3%) had been aware of the national osteoporosis clinical guideline. Knowledge and attitude scores among nurses who practice in private hospitals was higher than those practices in the teaching hospitals. These differences were statistically significant based on student t-test. According to Pearson correlation coefficient, there was positive and significant correlation between nurses’ knowledge and attitude score (Correlation coefficient: 0.199, p-value = 0.037).

Conclusion

Our findings reveal that nurses’ knowledge and attitude regarding osteoporosis was not satisfactory. Most of them were not aware of national osteoporosis clinical guideline and had not participated in osteoporosis training courses after their graduation. We need more empowered nurses to lowering burden of osteoporosis and its consequences in the future.

Effects of sleeve gastrectomy on bone mass, microstructure of femurs and bone metabolism associated serum factors in obese rats

BACKGROUND

Sleeve gastrectomy (SG) is a profoundly effective operation for severe obese patients, but is closely associated with bone mass loss. Previous studies have reported changes of various serum factors which may be associated with bone mass loss after SG. However, those results are contradictory. In this study, we assessed the effects of SG on bone mass, microstructure of femurs, and changes in bone turnover markers (BTMs), serum adipokines, inflammatory factors and gastrointestinal hormones after SG in high-fat diet (HFD) induced obese rats.

METHODS

Eight-week-old male Sprague-Dawley (SD) rats were fed with HFD to induce obesity. Then, SG and sham surgery were performed in anesthetized obese rats. SD rats in control group were fed with standard chow. Microstructure of femurs was scanned and analyzed by micro-computed tomography in control group, HFD sham group and HFD SG group. Serum inflammatory factors, adipokines markers, gastrointestinal hormones and BTMs were also measured.

RESULTS

Bone mineral density (BMD) of trabecular bone in both HFD sham group and HFD SG group were remarkably decreased compared with control group. All serum BTMs were significantly higher in HFD SG group than HFD sham group. In the meantime, serum levels of several important inflammatory factors, gastrointestinal hormones and adipokines such as tumor necrosis factor-α (TNF-α), interleukin (IL)-6, monocyte chemoattractant protein-1(MCP-1), ghrelin, insulin and leptin in HFD SG group were remarkably reduced compared with HFD sham group, whereas glucagon-like peptide-1 (GLP-1), adiponectin, fibroblast growth factor (FGF)-19 and FGF-21 were dramatically increased after SG. Protein tyrosine phosphatase 1B (PTP1B) was significantly increased in the HFD sham group than control group. Spearman's correlation analysis indicated that serum osteocalcin (OC) and 25-hydroxy vitamin D₃ (25(OH)D₃) were positively correlated with BMD of trabecular bone, whereas serum PTP1B and TNF-α were negatively related to BMD of trabecular bone.

CONCLUSIONS

SG aggravates bone mass loss and activates bone remodeling in obese rats. Levels of BTMs, adipokines, inflammatory factors, and gastrointestinal hormones could be affected by SG in obese rats. Serum PTP1B level might be associated with abnormal bone mass in obese rats.

Associations between Metabolic Syndrome and Obesity-Related Indices and Bone Mineral Density T-Score in Hemodialysis Patients

Previous studies have reported inconsistent results regarding the associations between metabolic syndrome (MetS) and obesity-related indices and bone mineral density (BMD). However, no previous studies have reported these associations among hemodialysis (HD) patients. The aims of this study were to investigate associations between MetS and its components and BMD T-score in HD patients and also between obesity-related indices and BMD T-score in HD patients with and without MetS. MetS was defined according to the Adult Treatment Panel III for Asians, and BMD T-score was calculated using dual-energy X-ray absorptiometry. Eight obesity-related indices were evaluated, including lipid accumulation product (LAP), visceral adiposity index (VAI), body adiposity index, conicity index (CI), body roundness index (BRI), abdominal volume index (AVI), waist-to-height ratio (WHtR), waist–hip ratio, and body mass index (BMI). One hundred and sixty-four patients undergoing HD were enrolled, and the prevalence of MetS was 61.6%. MetS was significantly associated with high lumbar spine and total hip T-scores. Regarding the MetS components, abdominal obesity and low HDL-C were significantly associated with high lumbar spine, femoral neck, and total hip T-scores; hypertriglyceridemia was significantly associated with high lumbar spine and total hip T-scores; hyperglycemia was significantly associated with a high lumbar spine T-score, whereas high blood pressure was not associated with T-score at any site. In the patients with MetS, BMI, WHtR, AVI, and BRI were significantly associated with T-score at all sites, and high CI, VAI, and LAP were also related to a high lumbar T-score. However, these indices were not associated with T-score at any site in patients without MetS. This study demonstrated positive associations between MetS and its five components and BMD T-score among HD patients. MetS, abdominal obesity, hypertriglyceridemia, and low HDL-cholesterol were associated with low risk of osteoporosis among the HD patients. Furthermore, we found that some obesity-related indices were associated with BMD T-score among HD patients with MetS but not in those without MetS. Our study highlights the importance of BMI, WHtR, AVI, and BRI in predicting the risk of osteoporosis among HD patients with MetS. In clinical practice, they can be easily calculated through simple anthropometric measurements and routine laboratory examinations and be used to quickly and conveniently assess the risk of osteoporosis among HD patients.

Particulate Air Pollution and Osteoporosis: A Systematic Review

Air pollution is associated with inflammation and oxidative stress, which predispose to several chronic diseases in human. Emerging evidence suggests that the severity and progression of osteoporosis are directly associated with inflammation induced by air pollutants like particulate matter (PM). This systematic review examined the relationship between PM and bone health or fractures. A comprehensive literature search was conducted from January until February 2021 using the PubMed, Scopus, Web of Science, Google Scholar and Cochrane Library databases. Human cross-sectional, cohort and case-control studies were considered. Of the 1500 papers identified, 14 articles were included based on the inclusion and exclusion criteria. The air pollution index investigated by most studies were PM2.5 and PM10. Current studies demonstrated inconsistent associations between PM and osteoporosis risk or fractures, which may partly due to the heterogeneity in subjects' characteristics, study design and analysis. In conclusion, there is an inconclusive relationship between osteoporosis risk and fracture and PM exposures which require further validation.

Analysis of ceRNA networks and identification of potential drug targets for drug-resistant leukemia cell K562/ADR

Background

Drug resistance is the main obstacle in the treatment of leukemia. As a member of the competitive endogenous RNA (ceRNA) mechanism, underlying roles of lncRNA are rarely reported in drug-resistant leukemia cells.

Methods

The gene expression profiles of lncRNAs and mRNAs in doxorubicin-resistant K562/ADR and sensitive K562 cells were established by RNA sequencing (RNA-seq). Expression of differentially expressed lncRNAs (DElncRNAs) and DEmRNAs was validated by qRT-PCR. The potential biological functions of DElncRNAs targets were identified by GO and KEGG pathway enrichment analyses, and the lncRNA-miRNA-mRNA ceRNA network was further constructed. K562/ADR cells were transfected with CCDC26 and LINC01515 siRNAs to detect the mRNA levels of GLRX5 and DICER1, respectively. The cell survival rate after transfection was detected by CCK-8 assay.

Results

The ceRNA network was composed of 409 lncRNA-miRNA pairs and 306 miRNA-mRNA pairs based on 67 DElncRNAs, 58 DEmiRNAs and 192 DEmRNAs. Knockdown of CCDC26 and LINC01515 increased the sensitivity of K562/ADR cells to doxorubicin and significantly reduced the half-maximal inhibitory concentration (IC₅₀) of doxorubicin. Furthermore, knockdown of GLRX5 and DICER1 increased the sensitivity of K562/ADR cells to doxorubicin and significantly reduced the IC₅₀ of doxorubicin.

Conclusions

The ceRNA regulatory networks may play important roles in drug resistance of leukemia cells. CCDC26/miR-140-5p/GLRX5 and LINC01515/miR-425-5p/DICER1 may be potential targets for drug resistance in K562/ADR cells. This study provides a promising strategy to overcome drug resistance and deepens the understanding of the ceRNA regulatory mechanism related to drug resistance in CML cells.

The Role of Osteoclast Energy Metabolism in the Occurrence and Development of Osteoporosis

In recent decades, the mechanism underlying bone metabolic disorders based on energy metabolism has been heavily researched. Bone resorption by osteoclasts plays an important role in the occurrence and development of osteoporosis. However, the mechanism underlying the osteoclast energy metabolism disorder that interferes with bone homeostasis has not been determined. Bone resorption by osteoclasts is a process that consumes large amounts of adenosine triphosphate (ATP) produced by glycolysis and oxidative phosphorylation. In addition to glucose, fatty acids and amino acids can also be used as substrates to produce energy through oxidative phosphorylation. In this review, we summarize and analyze the energy-based phenotypic changes, epigenetic regulation, and coupling with systemic energy metabolism of osteoclasts during the development and progression of osteoporosis. At the same time, we propose a hypothesis, the compensatory recovery mechanism (involving the balance between osteoclast survival and functional activation), which may provide a new approach for the treatment of osteoporosis.

Direct and Indirect Effect of Honey as a Functional Food Against Metabolic Syndrome and Its Skeletal Complications

Metabolic syndrome (MetS) refers to the simultaneous presence of hypertension, hyperglycemia, dyslipidemia and/or visceral obesity, which predisposes a person to cardiovascular diseases and diabetes. Evidence suggesting the presence of direct and indirect associations between MetS and osteoporosis is growing. Many studies have reported the beneficial effects of polyphenols in alleviating MetS in in vivo and in vitro models through their antioxidant and anti-inflammation actions. This review aims to summarize the effects of honey (based on unifloral and multi-floral nectar sources) on bone metabolism and each component of MetS. A literature search was performed using the PubMed and Scopus databases using specific search strings. Original studies related to components of MetS and bone, and the effects of honey on components of MetS and bone were included. Honey polyphenols could act synergistically in alleviating MetS by preventing oxidative damage and inflammation. Honey intake is shown to reduce blood glucose levels and prevent excessive weight gain. It also improves lipid metabolism by reducing total cholesterol, triglycerides and low-density lipoprotein, as well as increasing high-density lipoprotein. Honey can prevent bone loss by reducing the adverse effects of MetS on bone homeostasis, apart from its direct action on the skeletal system. In conclusion, honey supplementation could be integrated into the management of MetS and MetS-induced bone loss as a preventive and adjunct therapeutic agent.

Potential mechanisms linking psychological stress to bone health

Chronic psychological stress affects many body systems, including the skeleton, through various mechanisms. This review aims to provide an overview of the factors mediating the relationship between psychological stress and bone health. These factors can be divided into physiological and behavioural changes induced by psychological stress. The physiological factors involve endocrinological changes, such as increased glucocorticoids, prolactin, leptin and parathyroid hormone levels and reduced gonadal hormones. Low-grade inflammation and hyperactivation of the sympathetic nervous system during psychological stress are also physiological changes detrimental to bone health. The behavioural changes during mental stress, such as altered dietary pattern, cigarette smoking, alcoholism and physical inactivity, also threaten the skeletal system. Psychological stress may be partly responsible for epigenetic regulation of skeletal development. It may also mediate the relationship between socioeconomic status and bone health. However, more direct evidence is required to prove these hypotheses. In conclusion, chronic psychological stress should be recognised as a risk factor of osteoporosis and stress-coping methods should be incorporated as part of the comprehensive osteoporosis-preventing strategy.

Prevalence and Trends in Low Bone Density, Osteopenia and Osteoporosis in U.S. Adults With Non-Alcoholic Fatty Liver Disease, 2005-2014

BACKGROUND & AIMS

Non-alcoholic fatty liver disease (NAFLD) is suggested to be associated with bone mineral density (BMD) alterations; however, this has not been ascertained. The current study aimed to investigate the changes in BMD and the prevalence of osteopenia/osteoporosis in US adults with or without NAFLD and to evaluate their association.

METHODS

The study was conducted based on data collected from the U.S. National Health and Nutrition Examination Survey (NHANES) during the period 2005-2014. A total of 13 837 and 6 177 participants aged > 20 years were eligible for conducting the Hepatic Steatosis Index (HSI) and the US Fatty Liver Index (USFLI) analysis, respectively.

RESULTS

From 2005-2014, a downward trend in femoral neck BMD was observed in subjects with NAFLD aged ≥ 40. After adjustment for potential confounders, an upward shift occurred in the prevalence of osteopenia/osteoporosis at the femoral neck in adults aged ≥ 40, particularly in women ≥ 60 years old and men below the age of 60. Moreover, a negative association was found between BMD and NAFLD markers (USFLI, HSI), whereas NAFLD with advanced fibrosis was positively associated with the prevalence of spine fractures.

CONCLUSIONS

There was a trend toward lower BMD and higher prevalence of osteopenia/osteoporosis at the femoral neck in US adults with NAFLD aged ≥ 40 years during the period of 2005-2014. NAFLD with advanced fibrosis was positively associated with a higher risk of spine fracture. More research is required to fully investigate the mechanism and consequence of poor bone health in NAFLD patients and consider optimum management of osteopenia/osteoporosis for this population.

Palmatine as an Agent Against Metabolic Syndrome and Its Related Complications: A Review

Palmatine is a naturally occurring isoquinoline alkaloid with various pharmacological properties. Given its antioxidant and anti-inflammatory properties, palmatine may be able to impede the effects of metabolic syndrome (MetS) and its related diseases triggered by inflammation and oxidative stress. This review summarises the existing literature about the effects of palmatine supplementation on MetS and its complications. The evidence shows that palmatine could protect against MetS, and cardiovascular diseases, osteoporosis and osteoarthritis, which might be associated with MetS. These protective effects are mediated by the antioxidant and anti-inflammatory properties of palmatine. Although preclinical experiments have demonstrated the efficacy of palmatine against MetS and its related diseases, no human clinical trials have been performed to validate these effects. This research gap should be bridged to validate the efficacy and safety of palmatine supplementation in protecting humans against MetS and its related diseases.