Bone health in type 1 diabetes: focus on evaluation and treatment in clinical practice

Bone Fragility in Diabetes and its Management: A Narrative Review

Bone fragility is a serious yet under-recognised complication of diabetes mellitus (DM) that is associated with significant morbidity and mortality. Multiple complex pathophysiological mechanisms mediating bone fragility amongst DM patients have been proposed and identified. Fracture risk in both type 1 diabetes (T1D) and type 2 diabetes (T2D) continues to be understated and underestimated by conventional risk assessment tools, posing an additional challenge to the identification of at-risk patients who may benefit from earlier intervention or preventive strategies. Over the years, an increasing body of evidence has demonstrated the efficacy of osteo-pharmacological agents in managing skeletal fragility in DM. This review seeks to elaborate on the risk of bone fragility in DM, the underlying pathogenesis and skeletal alterations, the approach to fracture risk assessment in DM, management strategies and therapeutic options.

Two-sample Mendelian randomization studies revealed a causal relationship between insulin use and osteoporosis: An observational study

OBJECTIVE

To investigate causal associations between diabetes, insulin treatment and osteoporosis using LDSC analysis with a 2-way Mendelian randomization study.

METHODS

LDSC analysis was used to estimate the likelihood-scale heritability of the genome-wide association study used with genetic correlation between the 2 genome-wide association study used. Then a 2-sample Mendelian randomization study was performed using 3 methods including inverse variance weighted, MR Egger, and weighted median.

RESULTS

The genetic correlation between diabetes, insulin treatment (h2_Z = 3.70, P = 2.16e-4), osteoporosis (h2_Z = 4.93, h2_p = 8.13e-7) and genes was significant. There was a significant genetic correlation (rg = 0.122, P = 0.0211). There was a causal association between diabetes, insulin treatment and osteoporosis [P = 0.003754, OR (95%CI) = 0.998876 (0.998116-0.999636)], while no causal association existed between osteoporosis and insulin use (P = 0.998116-0.999636) causal association existed (P = 0.333244).

CONCLUSION

There was a strong genetic correlation between diabetes, insulin treatment and osteoporosis, a causal association between diabetes, insulin treatment and osteoporosis, and no causal association between osteoporosis and diabetes, insulin treatment.

Trabecular bone score in type 1 diabetes: a meta-analysis of cross-sectional studies

BACKGROUND

Bone fragility is a recognized complication of type 1 diabetes (T1D). Thus, lower trabecular bone score (TBS) measurements in T1D patients can be predicted. However, the results of current studies on TBS in patients with T1D are inconsistent. In this context, the present study aimed to test the hypothesis that T1D is associated with lower TBS through a meta-analysis.

METHODS

An electronic search of the literature was conducted using PubMed, Embase and Web of science databases to identify studies related to TBS and T1D, supplemented by an additional manual check of the reference list of relevant original and review articles. All data was analyzed using a random effects model. Results were compared using standardized mean differences (SMD) and 95% confidence intervals (CI). P ≤ 0.05 was considered statistically significant. Review Manager 5.4 software and Stata 17.0 software were used for statistical analysis.

RESULTS

Seven cross-sectional studies involving 848 participants were included. TBS was lower in T1D patients than in healthy controls on random effects analysis, with no heterogeneity (SMD =  - 0.39, 95% CI [- 0.53, - 0.24], P < 0.001; I2 = 0%). In addition, by subgroup analysis, T1D patients were strongly associated with reduced TBS in different regions and age groups, and the results were independent of covariate adjustment.

CONCLUSION

This study showed that TBS was lower in patients with T1D than in healthy individuals with normal blood glucose levels, suggesting that TBS may be a useful measure to assess fracture risk in T1D.

Advancing our understanding of the influence of drug induced changes in the gut microbiome on bone health

The gut microbiome has been implicated in a multitude of human diseases, with emerging evidence linking its microbial diversity to osteoporosis. This review article will explore the molecular mechanisms underlying perturbations in the gut microbiome and their influence on osteoporosis incidence in individuals with chronic diseases. The relationship between gut microbiome diversity and bone density is primarily mediated by microbiome-derived metabolites and signaling molecules. Perturbations in the gut microbiome, induced by chronic diseases can alter bacterial diversity and metabolic profiles, leading to changes in gut permeability and systemic release of metabolites. This cascade of events impacts bone mineralization and consequently bone mineral density through immune cell activation. In addition, we will discuss how orally administered medications, including antimicrobial and non-antimicrobial drugs, can exacerbate or, in some cases, treat osteoporosis. Specifically, we will review the mechanisms by which non-antimicrobial drugs disrupt the gut microbiome's diversity, physiology, and signaling, and how these events influence bone density and osteoporosis incidence. This review aims to provide a comprehensive understanding of the complex interplay between orally administered drugs, the gut microbiome, and osteoporosis, offering new insights into potential therapeutic strategies for preserving bone health.

Mechanisms Suggesting a Relationship between Vitamin D and Erectile Dysfunction: An Overview

Vitamin D deficiency (VDD) and erectile dysfunction (ED) heavily burden the male population. The higher prevalence of both conditions in the elderly suggests a possible relationship between the two conditions. In addition, in vitro, animal, and human studies have revealed several mechanisms that may relate VDD to ED. The main mechanism by which vitamin D might exert its action on sexual function appears to be through the regulation of endothelial function. Indeed, VDD correlates with several markers of endothelial function. The action of vitamin D on the endothelium would be exercised both indirectly through its intervention in inflammatory processes and through the production of oxygen free radicals, and directly through the regulation of vascular stiffness, the production of nitric oxide, and the regulation of vessel permeability. Furthermore, the ubiquitous distribution of the vitamin D receptor in the human body means that this hormone can also exert a beneficial effect on erectile function by interfering with those comorbidities significantly associated with ED, such as hypertension, diabetes mellitus, hypercholesterolemia, chronic kidney disease, and hypogonadism. In this review, we thoroughly and carefully presented the evidence and mechanisms that would appear to relate vitamin D levels to erectile function. Furthermore, we have summarized the meta-analytic evidence for and against this association to provide a true representation of this topic. Data published to date suggest that low levels of vitamin D could contribute to worsening erectile function through several mechanisms. Therefore, vitamin D levels should be measured in patients with ED and maintained at adequate levels by specific supplementation in case of deficiency. However, the low quality and heterogeneity of clinical trials evaluating the effects of vitamin D administration on erectile function and ED-associated comorbidities do not allow for a univocal conclusion, and indicate the need for further studies to analyze these aspects.

Exercise interventions for patients with type 1 diabetes mellitus: A narrative review with practical recommendations

Type 1 diabetes mellitus (T1DM) is a chronic endocrine disease that results from autoimmune destruction of pancreatic insulin-producing β cells, which can lead to microvascular (e.g., retinopathy, neuropathy, and nephropathy) and macro-vascular complications (e.g., coronary arterial disease, peripheral artery disease, stroke, and heart failure) as a consequence of chronic hyperglycemia. Despite the widely available and compelling evidence that regular exercise is an efficient strategy to prevent cardiovascular disease and to improve functional capacity and psychological well-being in people with T1DM, over 60% of individuals with T1DM do not exercise regularly. It is, therefore, crucial to devise approaches to motivate patients with T1DM to exercise, to adhere to a training program, and to inform them of its specific characteristics (e.g., exercise mode, intensity, volume, and frequency). Moreover, given the metabolic alterations that occur during acute bouts of exercise in T1DM patients, exercise prescription in this population should be carefully analyzed to maximize its benefits and to reduce its potential risks.

Low bone mineral density is associated with fatty liver disease and respiratory illness in a pediatric mortality sample

This study finds that fatty liver disease is associated with low bone density in a pediatric mortality sample. Since non-alcoholic fatty liver disease has increased in prevalence over the past few decades among children, a better understanding of the disease's impacts on bone health is of significance to clinicians.

PURPOSE

Chronic illness leads to decreased bone modeling and remodeling. This can be especially problematic during childhood and adolescence, since the majority of an individual's peak bone mass is achieved by the age of 20. In this study, we examine relationships between chronic illness and low bone mineral density (BMD) in a pediatric mortality sample (aged 0.5 to 20.9 years) from New Mexico. We also test whether low BMD is related to decelerated linear growth by examining its relationship to growth stunting and arrest (Harris lines).

METHODS

Hounsfield units (HU), a proxy for trabecular BMD, were obtained at the fourth lumbar vertebra and the femoral neck from postmortem CT scans. Linear regression was used to examine associations between z-standardized HU and age, sex, medical conditions, Harris lines, and growth stunting.

RESULTS

We find that lumbar HU is significantly lower for individuals with fatty liver disease and respiratory illness; femoral HU is significantly lower in individuals with Harris lines.

CONCLUSION

The mechanisms of low BMD in individuals with fatty liver disease and respiratory illness are likely multifactorial and involve vitamin D deficiency (malnutrition, malabsorption), systemic inflammation, and sedentary lifestyles. However, better awareness of this relationship can provide clinicians with the ability to introduce nutritional and behavioral interventions early to mitigate deleterious effects on bone. Harris lines, on the other hand, mark temporary growth cessation due to physiological stress followed by a rapid resumption of growth. Low BMD in these individuals may be due to bone mineralization lagging behind relatively rapid linear growth.

Causal relationship between Type 1 diabetes and osteoporosis and fracture occurrence: a two-sample Mendelian randomization analysis

We used two-sample Mendelian Randomization to reveal causal estimates of type 1 diabetes and bone. Type 1 diabetes was found to be a risk factor for bone metabolic health, although there was no clear evidence to support a genetic association between type 1 diabetes and osteoporosis and fracture risk.

INTRODUCTION

Based on the random assignment of gametes at conception, Mendelian randomization (MR) analysis simulates randomized controlled trials in an observational setting. Therefore, we used MR to assess the association causality of type 1 diabetes (T1D) with fractures and osteoporosis.

METHODS

From a genome-wide association meta-analysis, independent single nucleotide polymorphisms closely associated with T1D were selected as instrumental variables. Data on fracture and osteoporosis were obtained from the FinnGen Consortium. We performed a two-sample MR analysis, using inverse-variance weighted (IVW) as the primary analysis method, to assess possible causal associations between T1D and bone risk. The results were verified by MR-Egger regression and median weighted method (WME). MR-PRESSO and MR-Egger intercepts were used to evaluate the horizontal pleiotropy of instrumental variables, and the Q-test and "leave-one-out" methods were used to test the heterogeneity of MR results.

RESULTS

IVW (OR=1.040, 95% CI=0.974-1.109, P=0.238), MR-Egger regression (OR=1.077, 95% CI=0.921-1.260, P=0.372) and WME (OR=1.021, 95% CI=0.935-1.114, P=0.643) all showed that there was no causal relationship between T1D and osteoporosis, but the direction was consistent. The indicative significance of IVW results in T1D and forearm fractures (OR=1.062, 95% CI=1.010-1.117, P=0.020), but the results are not robust enough. There was no causal effect in femur, lumbar and pelvis, or shoulder and upper arm fractures.

CONCLUSIONS

After MR analysis, although T1D may be a risk factor for bone health, we do not have sufficient evidence to support a causal effect of T1D on osteoporosis and fractures at a genetically predicted level. More cases need to be included for analysis.

Diabetic Bone Disease and Diabetic Myopathy: Manifestations of the Impaired Muscle-Bone Unit in Type 1 Diabetes

Type 1 diabetes is associated with complications affecting muscle and bone, with diabetic bone disease and diabetic myopathy becoming increasingly reported in the past few decades. This review is aimed at succinctly reviewing the literature on the current knowledge regarding these increasingly identified and possibly interconnected complications on the musculoskeletal system. Furthermore, this review summarizes several nonmechanical factors that could be mediating the development and progression of premature musculoskeletal decline in this population and discusses preventative measures to reduce the burden of diabetes on the musculoskeletal system.

Bone Density, Geometry, and Mass by Peripheral Quantitative Computed Tomography and Bone Turnover Markers in Children with Diabetes Mellitus Type 1

BACKGROUND

The type 1 diabetes mellitus (T1DM) is a chronic systemic autoimmune-mediated disease characterised by the insulin deficiency and hyperglycaemia. Its deleterious effect on bones concerns not only bone mass, density, and fracture risk but also may involve the linear growth of long bones. Studies on the lower leg in children with T1DM by pQCT have generated conflicting results, and most of the studies published so far focused only on a selected features of the bone. An additional information about growth, modelling, and remodelling processes can be gathered by the bone turnover marker measurement. The objective of the study was to evaluate bone mineral density, mass, and geometry using peripheral quantitative computed tomography as well as bone turnover markers in the patients with type 1 diabetes mellitus. Material and Methods. Bone mineral density, mass, and geometry on the lower leg using peripheral quantitative computed tomography and serum osteocalcin (OC) and carboxyterminal cross-linked telopeptide of type 1 collagen (CTx) were measured in 35 adolescents with T1DM (15 girls) aged 12.3-17.9 yrs. The results were compared to age- and sex-adjusted reference values for healthy controls.

RESULTS

Both sexes reveal lower than zero Z-scores for lower leg 66% total cortical bone cross-sectional area to muscle cross-sectional area ratio (-0.97 ± 1.02, p = 0.002517 and -0.98 ± 1.40, p = 0.007050, respectively) while tibia 4% trabecular bone density Z-score was lowered in boys (-0.67 ± 1.20, p = 0.02259). In boys in Tanner stage 5 bone mass and dimensions were diminished in comparison to Tanner stages 3 and 4, while in girls, such a phenomenon was not observed. Similarly, bone formation and resorption were decreased in boys but not in girls. Consistently, bone turnover markers correlated positively with bone size, dimensions, and strength in boys only.

CONCLUSIONS

T1DM patients revealed a decreased ratio of cortical bone area/muscle area, reflecting disturbed adaptation of the cortical shaft to the muscle force. When analyzing bone mass and dimensions, boys in Tanner stage 5 diverged from "less-mature" individuals, which may suggest that bone development in these individuals was impaired, affecting all three: mass, size, and strength. Noted in boys, suppressed bone metabolism may result in impairment of bone strength because of inadequate repair of microdamage and accumulation of microfractures.

Ficus deltoidea promotes bone formation in streptozotocin-induced diabetic rats

CONTEXT

Diabetes mellitus increases the risk of bone diseases including osteoporosis and osteoarthritis. We have previously demonstrated that Ficus deltoidea Jack (Moraceae) is capable of reducing hyperglycaemia. However, whether F. deltoidea could protect against diabetic osteoporosis remains to be determined.

OBJECTIVE

The study examines the effect of F. deltoidea on bone histomorphometric parameters, oxidative stress, and turnover markers in diabetic rats.

MATERIALS AND METHODS

Streptozotocin (STZ)-induced diabetic Sprague-Dawley rats (n = 6 animals per group) received one of the following treatments via gavage for 8 weeks: saline (diabetic control), metformin (1000 mg/kg bwt), and methanol leaves extract of F. deltoidea (1000 mg/kg bwt). A group of healthy rats served as normal control. The femoral bones were excised and scanned ex vivo using micro-computed tomography (micro-CT) for histomorphometric analysis. The serum levels of insulin, oxidative stress, and bone turnover markers were determined by ELISA assays.

RESULTS

Treatment of diabetic rats with F. deltoidea could significantly increase bone mineral density (BMD) (from 526.98 ± 11.87 to 637.74 ± 3.90). Higher levels of insulin (2.41 ± 0.08 vs. 1.58 ± 0.16), osteocalcin (155.66 ± 4.11 vs. 14.35 ± 0.97), and total bone n-3 PUFA (2.34 ± 0.47 vs. 1.44 ± 0.18) in parallel with the presence of chondrocyte hypertrophy were also observed following F. deltoidea treatment compared to diabetic control.

CONCLUSIONS

F. deltoidea could prevent diabetic osteoporosis by enhancing osteogenesis and inhibiting bone oxidative stress. These findings support the potential use of F. deltoidea for osteoporosis therapy in diabetes.

Effect of gender, diabetes duration, inflammatory cytokines, and vitamin D level on bone mineral density among Thai children and adolescents with type 1 diabetes

INTRODUCTION

Type 1 diabetes mellitus (T1DM) is considered a risk factor for osteoporosis in adults; however, studies in bone mineral density (BMD) in children with T1DM reported conflicting results. The aim of this study was to compare BMD between T1DM youth and healthy controls, and to identify factors that affect BMD in T1DM youth.

METHODS

One hundred T1DM youths and 100 healthy controls (both groups aged 5-20 years) were recruited. BMD of total body, lumbar (L2-4), femoral neck, and total hip were assessed using dual energy X-ray absorptiometry. Blood investigations, including hemoglobin A_1c (HbA_1c), 25-hydroxyvitamin D, and inflammatory cytokines, were performed.

RESULTS

Forty-four boys and 56 girls with T1DM were enrolled [mean age 14.5 ± 2.7 years, median (IQR) duration of T1DM 5.80 (2.97-9.07) years, and mean HbA_{1c entire duration} 9.2 ± 1.4%]. T1DM girls had a lower height Z-score than control girls (p < 0.05), and 25-hydroxyvitamin D level was higher in T1DM youth than in controls (p < 0.001). After adjusting for pubertal status, height Z-score, and 25-hydroxyvitamin D, T1DM youth had a significantly lower lumbar BMD Z-score and femoral neck BMD than controls (p = 0.027 and p = 0.025, respectively). We also found that T1DM boys had a significantly lower lumbar BMD Z-score (p = 0.028), femoral neck BMD (p = 0.004), and total hip BMD (p = 0.016) than control boys. In contrast, these significant differences were not found in T1DM girls. Factors affecting BMD were different between T1DM boys and girls, and among different BMD sites. IL-13 was positively correlated with BMD in the total cohort and among girls. In boys - IL-2 and 25-hydroxyvitamin D were positively associated with BMD, and duration of diabetes was found to negatively affect BMD.

CONCLUSION

Deleterious effect of T1DM on BMD is gender specific. The longer the duration of T1DM, the greater the deficit in BMD found among boys with T1DM.

Sex-Specific Effects of Vitamin D Status on the Metabolic Profile in Prediabetic Subjects

INTRODUCTION

We aim to investigate the effect of vitamin D on metabolic parameters in a population with prediabetes and to detect possible sex differences.

METHODS

In 621 patients with diagnosed prediabetes, glucose, lipid, and anthropometric parameters were measured. Furthermore, the interaction of 25-OH-vitamin D (25-hydroxyvitamin D) with metabolic and glucose metabolism parameters was analysed in the total prediabetic population, as well as after stratification by sex (female vs. male prediabetic subgroup), by logistic regression.

RESULTS

25-OH-vitamin D was negatively related to cholesterol, BMI, fatty liver index, insulin, and HOMA-IR. Especially in the male prediabetic cohort, 25-OH-vitamin D levels negatively correlated with total cholesterol levels (r = -0.17, p=0.001), with triglycerides (r = -0.17, p=0.001), and with HbA1c levels (r = -0.14, p=0.010). Only in the female cohort with prediabetes, we found a negative correlation of 25-OH-vitamin D levels with systolic (r = -0.18, p=0.005) and diastolic blood pressures (r = -0.23, p < 0.001).

CONCLUSION

In this study, in females with prediabetes, 25-OH-vitamin D was notably related to a more favourable metabolic profile, including lower total cholesterol and higher HDL cholesterol levels. On the contrary, in men with prediabetes, there was a stronger association between 25-OH-vitamin D and cholesterol-HDL quotient, as well as fatty liver index was observed in the male prediabetic subgroup. Therefore, sex differences should be considered in future studies on vitamin D and glucose tolerance status.

Lower bone mineral density and higher bone resorption marker levels in premenopausal women with type 1 diabetes in Japan

AIMS/INTRODUCTION

Type 1 diabetes is associated with poorer bone quality. Quantitative ultrasound provides an estimate of bone mineral density (BMD) and can also be used to evaluate bone quality, which is associated with an increased fracture risk in people with type 1 diabetes. The aim of this study was to evaluate the association between menopausal status and a bone turnover marker with heel BMD using quantitative ultrasound in women with type 1 diabetes and age- and body mass index-matched controls.

MATERIALS AND METHODS

A total of 124 individuals recruited in Kyoto and Osaka, Japan - 62 women with type 1 diabetes (mean age 47.2 ± 17.3 years) and 62 age-, menopausal status-, sex- and body mass index-matched non-diabetic control individuals (mean age 47.3 ± 16.3 years) - were enrolled in this study. Heel BMD in the calcaneus was evaluated using ultrasonography (AOS-100NW, Hitachi-Aloka Medical, Ltd., Tokyo, Japan). A bone turnover marker was also measured.

RESULTS

The heel BMD Z-score was significantly lower in premenopausal women with type 1 diabetes than in the premenopausal control group, but not in postmenopausal women with type 1 diabetes. Levels of tartrate-resistant acid phosphatase-5b, a bone resorption marker, were significantly higher in premenopausal women with type 1 diabetes than in the premenopausal control group, but not in postmenopausal women with type 1 diabetes. The whole parathyroid hormone level was significantly lower in both pre- and postmenopausal women with type 1 diabetes.

CONCLUSIONS

Lower heel BMD, higher tartrate-resistant acid phosphatase-5b level and lower parathyroid hormone were observed in premenopausal women with type 1 diabetes. Premenopausal women with type 1 diabetes require osteoporosis precautions for postmenopause.

Critical review of bone health, fracture risk and management of bone fragility in diabetes mellitus

The risk of fracture is increased in both type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). However, in contrast to the former, patients with T2DM usually possess higher bone mineral density. Thus, there is a considerable difference in the pathophysiological basis of poor bone health between the two types of diabetes. Impaired bone strength due to poor bone microarchitecture and low bone turnover along with increased risk of fall are among the major factors behind elevated fracture risk. Moreover, some antidiabetic medications further enhance the fragility of the bone. On the other hand, antiosteoporosis medications can affect the glucose homeostasis in these patients. It is also difficult to predict the fracture risk in these patients because conventional tools such as bone mineral density and Fracture Risk Assessment Tool score assessment can underestimate the risk. Evidence-based recommendations for risk evaluation and management of poor bone health in diabetes are sparse in the literature. With the advancement in imaging technology, newer modalities are available to evaluate the bone quality and risk assessment in patients with diabetes. The purpose of this review is to explore the pathophysiology behind poor bone health in diabetic patients. Approach to the fracture risk evaluation in both T1DM and T2DM as well as the pragmatic use and efficacy of the available treatment options have been discussed in depth.

Diabetes and Osteoporosis: Part I, Epidemiology and Pathophysiology

Both diabetes and osteoporosis are increasingly prevalent diseases, in part owing to aging populations worldwide. Epidemiologic data have shown that other organs may be adversely affected by diabetes, including the skeleton, in what has become known as diabetes-induced osteoporosis, which represents the combined impact of conventional osteoporosis with the additional fracture burden attributed to diabetes. There is an increased risk of fracture in patients with Type 1 and Type 2 diabetes, and some antidiabetic medications also may contribute to increased risk of fracture in diabetes.

Renal Proximal Tubule Cell Cannabinoid-1 Receptor Regulates Bone Remodeling and Mass via a Kidney-to-Bone Axis

The renal proximal tubule cells (RPTCs), well-known for maintaining glucose and mineral homeostasis, play a critical role in the regulation of kidney function and bone remodeling. Deterioration in RPTC function may therefore lead to the development of diabetic kidney disease (DKD) and osteoporosis. Previously, we have shown that the cannabinoid-1 receptor (CB1R) modulates both kidney function as well as bone remodeling and mass via its direct role in RPTCs and bone cells, respectively. Here we employed genetic and pharmacological approaches that target CB1R, and found that its specific nullification in RPTCs preserves bone mass and remodeling both under normo- and hyper-glycemic conditions, and that its chronic blockade prevents the development of diabetes-induced bone loss. These protective effects of negatively targeting CB1R specifically in RPTCs were associated with its ability to modulate erythropoietin (EPO) synthesis, a hormone known to affect bone mass and remodeling. Our findings highlight a novel molecular mechanism by which CB1R in RPTCs remotely regulates skeletal homeostasis via a kidney-to-bone axis that involves EPO.

Comparison of differences in bone microarchitecture in adult- versus juvenile-onset type 1 diabetes Asian males versus non-diabetes males: an observational cross-sectional pilot study

PURPOSE

Evidence about bone microarchitecture in Asian type 1 diabetes (T1D) patients is lacking. We assessed the bone microarchitecture in T1D patients versus controls and compare the differences between juvenile-onset and adult-onset T1D patients.

METHODS

This cross-sectional study recruited 32 Asian males with T1D and 32 age-, sex-, and body mass index (BMI)-matched controls. Dual-energy X-ray absorptiometry (DXA) and high-resolution peripheral quantitative computed tomography (HR-pQCT) for ultradistal nondominant radius and tibia were performed. The data were analyzed using Student's t test and analysis of covariance.

RESULTS

Among the patients, 15 had juvenile-onset T1D, with a median disease duration of 11 years, and 17 had adult-onset T1D, with a median disease duration of 7 years. At the radius, adult-onset and juvenile-onset T1D patients had lower total volumetric bone mineral density (vBMD), trabecular vBMD, trabecular bone volume fraction (BV/TV), and trabecular thickness (Tb.Th) (p < 0.05) than the control subjects. After adjusting for BMI, disease duration, and insulin dose, juvenile-onset patients tended to have lower trabecular vBMD, BV/TV, Tb.Th, and intracortical porosity (Ct.Po) than adult-onset patients. At the tibia, adult-onset patients displayed lower total vBMD, lower Ct. vBMD, and higher Ct.Po (p < 0.05), while juvenile-onset patients had lower Tb.Th and standard deviation of trabecular number (1/Tb.N.SD) (p < 0.05) than control subjects. After adjustment for covariates, adult-onset patients tended to have higher cortical pore diameter (Ct.Po.Dm) than juvenile-onset patients.

CONCLUSIONS

T1D patients were associated with compromised bone microarchitecture, adult-onset and juvenile-onset T1D patients demonstrated some differences in cortical and trabecular microarchitecture.

Inhibition of tanshinone IIA on renin activity protected against osteoporosis in diabetic mice

Context: Salvia miltiorrhiza Bge. (Labiatae) (SMB) is applied clinically for management of diabetic osteoporosis in China, and research results has suggested its potential action on renin-angiotensin system (RAS).Objective: This study screens and explores naturally occurring bioactive constituents from the root of SMB acting on renin activity and evaluates its osteoprotective efficacy in diabetic mice.Materials and methods: Human embryonic kidney (HEK) 293 cells, engineered to express human renin, were used as an in vitro model to identify bioactive compound, tanshinone IIA, inhibiting renin activity. The C57BL/6 mice (n = 10 in each group) with diabetes induced by streptozotocin (STZ) were intraperitoneally injected with tanshinone IIA (10 and 30 mg/kg). The mice without STZ treatment and the diabetic mice treated with aliskiren were used as non-diabetic control and positive control, respectively.Results: Tanshinone IIA was found to display inhibitory effects on renin activity of HEK-293 cells; moreover, it down-regulated protein expression of ANG II in human renin-expressed HEK-293 cells. Treatment of diabetic mice with tanshinone IIA with both doses could significantly decrease ANG II level in serum (from 16.56 ± 1.70 to 10.86 ± 0.68 and 9.14 ± 1.31 pg/mL) and reduce ANG II expression in bone, consequently improving trabecular bone mineral density and micro-structure of proximal tibial end and increasing trabecular bone area of distal femoral end in diabetic mice.Conclusions: This study revealed beneficial effects of tanshinone IIA on bone of diabetic mice, and potentially suggested the application of Salvia miltiorrhiza in the treatment of osteoporosis and drug development of tanshinone IIA as a renin inhibitor.

Understanding Bone Disease in Patients with Diabetic Kidney Disease: a Narrative Review

PURPOSE OF REVIEW

Both diabetes and kidney disease associate with the development of bone disease and an increased risk of fragility fractures. The etiologies of bone disease in patients with diabetic kidney disease (DKD) are multiple and complex. This review explores the association between DKD and bone disease and discusses how the presence of both diabetes and kidney disease may impair bone quality and increase fracture risk. Diagnostic tools as well as future research areas are also discussed.

RECENT FINDINGS

Patients with DKD have an increased risk of fragility fracture, most pronounced in patients with type 1 diabetes, and in DKD a high prevalence of adynamic bone disease is found. Recent studies have demonstrated disturbances in the interplay between bone regulating factors in DKD, such as relative hypoparathyroidism and alterations of bone-derived hormones including fibroblast growth factor-23 (FGF-23), sclerostin and klotho, which lead to bone disease. This review examines the current knowledge on bone disease in patients with DKD, clinical considerations for patient care, as well as subjects for future research.

Sulfonylurea and fracture risk in patients with type 2 diabetes mellitus: A meta-analysis

AIMS

This meta-analysis was conducted to investigate the fracture risk among patients with T2DM treated with sulfonylurea.

METHODS

The PubMed and other databases were searched for eligible studies. Both randomized controlled trials and observational studies that compared the fracture risk of sulfonylurea to other hypoglycemic agents were included. Pooled risk ratios and 95% confidence intervals were calculated. Subgroup analysis and meta-regression analyses were conducted to explore the source of heterogeneity.

RESULTS

A total of 11 studies involving 255,644 individuals were included in our meta-analysis. In comparing sulfonylurea users with patients who had not taken sulfonylurea, the pooled risk ratio for developing fracture was 1.14 (95% confifidence interval, 1.08-1.19). In subgroup analyses, the pooled risk ratio of bone fracture in patients receiving sulfonylurea versus thiazolidinedione, metformin and insulin was 0.90 (95% CI, 0.76-1.06), 1.25 (95% CI, 1.18-1.32) and 0.81 (95% CI, 0.74-0.89) respectively. Meta regression showed that age and gender were not related to the effect of sulfonylurea on fracture.

CONCLUSIONS

Sulfonylurea use was associated with 14% increase in the risk of developing fracture in T2DM. The risk of fracture caused by sulfonylurea was similar to thiazolidinedione, higher than metformin and lower than insulin.

Effects of Diabetes on Bone Material Properties

PURPOSE OF REVIEW

Individuals with type 1 and type 2 diabetes mellitus (T1DM, T2DM) have an increased risk of bone fracture compared to non-diabetic controls that is not explained by differences in BMD, BMI, or falls. Thus, bone tissue fracture resistance may be reduced in individuals with DM. The purpose of this review is to summarize work that analyzes the effects of T1DM and T2DM on bone tissue compositional and mechanical properties.

RECENT FINDINGS

Studies of clinical T2DM specimens revealed increased mineralization and advanced glycation endproduct (AGE) concentrations and significant relationships between mechanical performance and composition of cancellous bone. Specifically, in femoral cancellous tissue, compressive stiffness and strength increased with mineral content; and post-yield properties decreased with AGE concentration. In addition, cortical resistance to in vivo indentation (bone material strength index) was lower in patients with T2DM vs. age-matched non-diabetic controls, and this resistance decreased with worsening glycemic control. Recent studies on patients with T1DM and history of a prior fragility fracture found greater mineral content and concentrations of AGEs in iliac trabecular bone and correspondingly stiffer, harder bone at the nanosacle. Recent observational data showed greater AGE and mineral content in surgically retrieved bone from patients with T2DM vs. non-DM controls, consistent with reduced bone remodeling. Limited data on human T1DM bone tissue also showed higher mineral and AGE content in patients with prior fragility fractures compared to non-DM and non-fracture controls.

Systematic review: associations of calcium intake, vitamin D intake, and physical activity with skeletal outcomes in people with Type 1 diabetes mellitus

AIMS

The skeletal complications of type 1 diabetes (T1D) include low bone density, poor bone quality and fractures. Greater calcium intake, vitamin D intake, and physical activity are commonly recommended to improve bone health in patients with T1D. However, it is not clear whether these factors are affected by T1D or improve clinical outcomes.

METHODS

The objective of this study was to systematically review the literature for evidence of associations between calcium intake, vitamin D intake, and physical activity and skeletal outcomes in T1D. In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, twenty-two studies were included in this review.

RESULTS

The prevalence of calcium deficiency was high and encompassed greater than 50% of participants in the majority of studies. Despite this finding, there was no clear association between calcium intake and bone density in any study. Calcitriol use was associated with gains in bone density in one study but was not associated with changes in bone turnover markers in a second report. No studies specifically investigated the impact of vitamin D2 or D3 supplementation on bone health. Two studies reported a beneficial effect of physical activity interventions on bone accrual in children. The findings from observational studies of physical activity were mixed.

CONCLUSION

There are insufficient data to determine if deficient calcium intake, vitamin D intake, or physical activity contributes to the skeletal complications of T1D. Future studies specifically designed to assess the impact of these interventions on the skeleton in T1D participants are needed.

Bone health in diabetes and prediabetes

Bone fragility has been recognized as a complication of diabetes, both type 1 diabetes (T1D) and type 2 diabetes (T2D), whereas the relationship between prediabetes and fracture risk is less clear. Fractures can deeply impact a diabetic patient's quality of life. However, the mechanisms underlying bone fragility in diabetes are complex and have not been fully elucidated. Patients with T1D generally exhibit low bone mineral density (BMD), although the relatively small reduction in BMD does not entirely explain the increase in fracture risk. On the contrary, patients with T2D or prediabetes have normal or even higher BMD as compared with healthy subjects. These observations suggest that factors other than bone mass may influence fracture risk. Some of these factors have been identified, including disease duration, poor glycemic control, presence of diabetes complications, and certain antidiabetic drugs. Nevertheless, currently available tools for the prediction of risk inadequately capture diabetic patients at increased risk of fracture. Aim of this review is to provide a comprehensive overview of bone health and the mechanisms responsible for increased susceptibility to fracture across the spectrum of glycemic status, spanning from insulin resistance to overt forms of diabetes. The management of bone fragility in diabetic patient is also discussed.

Retrospective Analysis of Bone Metabolism in Patients on Waiting List for Simultaneous Pancreas-Kidney Transplantation

Posttransplant osteoporosis, which evolves from preexisting bone pathologies, represents a serious complication with deteriorating consequences. The aim of our study was to evaluate epidemiological data on bone mineral density (BMD) in subjects with type 1 diabetes (T1DM) in advanced stages of diabetic nephropathy indicated for simultaneous pancreas-kidney transplantation (SPK). We retrospectively compiled biochemical and densitometrical data from 177 patients with T1DM at CKD (chronic kidney disease) stages G4-G5 (115 men, 62 women, median age 40 yr, diabetes duration 23 yr) enrolled on waiting list for SPK for the first time between the years 2011 and 2016. Median Z-scores were as follows: lumbar spine (LS): -0.8 [interquartile range -1.75 to 0.1]; total hip (TH): -1.2 [-1.75 to -0.6]; femoral neck (FN): -1.2 [-1.9 to -0.7]; and distal radius (DR): -0.8 [-1.4 to -0.1]. We noted a gender difference in LS, with worse results for men (-1.1 vs. -0.3) even after adjusting for BMI (body mass index) and glomerular filtration (p < 0.001). Osteoporotic and osteopenic ranges (based on T-scores) for all major sites were 27.7% and 56.5%, respectively, with similar results across both genders. Women had a significantly higher proportion of normal BMD in LS than men (67.7 vs. 49.4%, p < 0.05). Patients with T1DM at CKD stages G4-G5 exhibited serious BMD impairment despite their young age. Men surprisingly displayed lower Z-scores and higher percentages of pathological BMD values in LS than women did. The introduction of adequate preventive measures during the advanced stages of diabetic nephropathy to prevent bone loss is recommended.

Tetrahydroxy stilbene glucoside protected against diabetes-induced osteoporosis in mice with streptozotocin-induced hyperglycemia

Tetrahydroxy stilbene glucoside (TSG), an active component from medicinal herb Polygonum multiflorum Thunb, could block the activity of the tissue renin-angiotensin system (RAS), which plays a critical role in development of diabetic osteoporosis. This study aimed to determine if TSG therapy could alleviate bone deteriorations in diabetic mouse model induced by streptozotocin. The diabetic mice showed the loss of trabecular bone mass and the changes of trabecular bone microarchitectural parameters as well as the increase in amount of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts at the distal metaphysis of femur when compared with those of nondiabetic mice. Treatment with TSG significantly elevated calcium content in serum and bone and improved biological parameters of trabecular bone, accompanied by increasing messenger RNA (mRNA) expression of RUNX-2, COL-I, and OCN and protein expression of β-catenin as well as down-regulating protein expression of RAS components including renin and AT1R. In addition, TSG repressed diabetes-induced decrease in ratio of OPG/RANKL expression and increase in sclerostin expression in bone. The similar effects of TSG on osteoblasts-specific genes were found in MC3T3-E1 cells. Taken together, the present study demonstrated the osteopreserve effects of TSG in diabetic mice, and the underlying mechanism might be attributed to its regulation on osteogenesis and osteoclastogenesis.

Association Between Vitamin D and Carboxy-Terminal Cross-Linked Telopeptide of Type I Collagen in Children During Growth Hormone Replacement Therapy

Growth hormone and insulin-like growth factor-1 (IGF-1) play a crucial role in the regulation of bone turnover. Adequate vitamin D status supports proper bone remodeling, leading to normal longitudinal bone growth and normal peak bone mass. The aim of this study was to evaluate the association between serum 25-hydroxyvitamin D [25(OH)D] and carboxy-terminal cross-linked telopeptide of type I collagen (ICTP) in children and adolescents with growth hormone deficiency at baseline and during recombinant human growth hormone (rhGH) replacement therapy. The study was prospective and included 30 children and adolescents aged 5 to 17 years. Concentrations of 25(OH)D, ICTP, and IGF-1 were measured at baseline and during the first year of rhGH therapy. Baseline serum 25(OH)D concentration correlated with ICTP concentrations during the first trimester of rhGH therapy (r = 0.38, p < 0.050); the correlation was stronger in the second trimester of therapy (r = 0.6, p = 0.002). We conclude that proper vitamin D status is important in reaching the adequate dynamics of bone remodeling during growth, which is essential to achieve a catch-up growth during rhGH therapy.

Evaluation of bone mineral status in prepuberal children with newly diagnosed type 1 diabetes

PURPOSE

Many studies have reported that patients with type 1 diabetes have reduced bone mineral density (BMD). We assessed bone status in prepubertal children with type 1 diabetes mellitus (type 1 DM) at initial diagnosis and investigated factors associated with BMD.

METHODS

Prepubertal children (n=29) with newly diagnosed type 1 diabetes from 2006 to 2014 were included. Dual-energy X-ray absorptiometry measured regional and whole-body composition at initial diagnosis. BMD was compared with healthy controls matched for age, sex, and body mass index (BMI).

RESULTS

The mean age of all subjects (16 boys and 13 girls) was 7.58±1.36 years (range, 4.8-11.3 years). Initial mean glycosylated hemoglobin (HbA1c) level was 12.2%±1.9%. The mean BMD z-scores of lumbar spine, femur neck, and total body were not significantly different between patients and controls. Three patients (10.3%) had low bone density (total body BMD standard deviation score [SDS] &lt; -2.0). To identify determinants of lumbar spine BMD z-score, multivariate regression analysis was performed with stepwise variable selection of age, pubertal status, BMI SDS, insulin like growth factor-1, and HbA1c. Only BMI SDS was significantly correlated with lumbar spine BMD z-score (β=0.395, P=0.023).

CONCLUSION

Prepubertal children with newly diagnosed type 1 DM had similar bone mass compared to healthy peers. However, patients with low BMI should be carefully monitored for bone density in type 1 DM.

Fracture risk in young and middle-aged adults with type 1 diabetes mellitus: A systematic review and meta-analysis

BACKGROUND

Type 1 diabetes mellitus (T1DM) is associated with skeletal fragility. While previous meta-analyses have demonstrated an increased risk of fracture in individuals with T1DM, little is known about fracture risk in T1DM, in the absence of age-related confounders.

AIMS

To determine the risk of fracture in young and middle-aged adults with T1DM aged 18-50 years old.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Ovid MEDLINE, PubMed, EMBASE, EBM reviews and relevant conference abstracts.

STUDY INCLUSION CRITERIA

Studies of adults aged between 18-50 years with type 1 diabetes mellitus, with reported fracture outcomes.

PRIMARY OUTCOMES

Incident or prevalent fracture.

RESULTS

Six studies were included in the meta-analysis. A total of 1724 fractures occurred in 35 925 patients with T1DM and 48 253 fractures occurred in 2 455 016 controls. RR for all fractures was 1.88 (95% CI 1.52-2.32, P < .001). Fifty-six hip fractures occurred among 34 707 patients with T1DM and 594 hip fractures occurred in 2 295 177 controls. The RR of hip fractures was 4.40 (95% CI 2.58-7.50, P < .001). Females and males with T1DM had a RR of 5.79 (95% CI 3.55-9.44, P < .001) and 3.67 (95% CI 2.10-6.41, P < .001), respectively.

CONCLUSIONS

In the absence of age-related comorbidities, fracture risk remains significantly elevated in young and middle-aged adults with T1DM. Younger age does not mitigate against hip fracture risk in T1DM, and health professionals need to be aware of this risk. Further studies are needed to evaluate the mechanisms of fracture in T1DM.

Recurrent vertebral fractures in a young adult: a closer look at bone health in type 1 diabetes mellitus

The association between type 1 diabetes mellitus (T1DM) and bone health has garnered interest over the years. Fracture risk is known to be increased in individuals with T1DM, although bone health assessment is not often performed in the clinical setting. We describe the case of a 21-year-old male with longstanding T1DM with multilevel vertebral fractures on imaging, after presenting with acute back pain without apparent trauma. Dual-energy X-ray absorptiometry (DXA) revealed significantly reduced bone mineral density at the lumbar spine and femoral neck. Extensive investigations for other secondary or genetic causes of osteoporosis were unremarkable, apart from moderate vitamin D deficiency. High-resolution peripheral quantitative computed tomography and bone biospy revealed significant alterations of trabecular bone microarchitecture. It later transpired that the patient had sustained vertebral fractures secondary to unrecognised nocturnal hypoglycaemic seizures. Intravenous zoledronic acid was administered for secondary fracture prevention. Despite anti-resorptive therapy, the patient sustained a new vertebral fracture after experiencing another hypoglycaemic seizure in his sleep. Bone health in T1DM is complex and not well understood. There are significant challenges in the assessment and management of osteoporosis in T1DM, particularly in young adults, where fracture prediction tools have not been validated. Clinicians should be aware of hypoglycaemia as a significant risk factor for fracture in patients with T1DM.

Learning points

Type 1 diabetes mellitus (T1DM) is a secondary cause of osteoporosis, characterised by reduced bone mass and disturbed bone microarchitecture.Hypoglycaemic seizures generate sufficient compression forces along the thoracic column and can cause fractures in individuals with compromised bone quality.Unrecognised hypoglycaemic seizures should be considered in patients with T1DM presenting with fractures without a history of trauma.Patients with T1DM have increased fracture risk and risk factors should be addressed. Evaluation of bone microarchitecture may provide further insights into mechanisms of fracture in T1DM.Further research is needed to guide the optimal screening and management of bone health in patients with T1DM.

Association between low C-peptide and fragility fractures in postmenopausal women without diabetes

PURPOSE

C-peptide has been shown to exert several, previously unknown, biological effects. A recent cross-sectional study demonstrated an association between low C-peptide serum levels and low lumbar bone density of postmenopausal women not affected by diabetes. To date, very little research attention has been directed toward the association between C-peptide and osteoporotic fractures. To contribute toward filling this gap, we investigated the association between C-peptide and fractures in postmenopausal women.

METHODS

A cohort of 133 non-diabetic postmenopausal women with and without a history of fractures was evaluated in this cross-sectional investigation. Standardized interviews were performed to gather information on the patients' fracture history. All of the participants underwent a bone mineral density assessment by DXA, radiographs, and a serum C-peptide measurement.

RESULTS

Thirty-four women presented fractures. Bivariate analysis revealed an inverse correlation between C-peptide and fractures (r = -0.27, p = 0.002). A significant difference in mean C-peptide levels was also found between women with vs. without fractures (p = 0.01, adjusted for age, BMI and glucose). Logistic regression analysis showed that C-peptide levels, femoral and vertebral BMD were all negatively associated with fracture status (B = -1.097, ES = 0.401, p = 0.006, 95% CI 0.15-0.73; B = -15.6, SE = 4.17, p < 0.001, CI 0.001-0.002; B = -24.8, SE = 5.23, p < 0.001, CI 0001-0.002; respectively).

CONCLUSIONS

This study confirms an inverse association between serum C-peptide levels and a history of fractures in postmenopausal women without diabetes. These results suggest that C-peptidemay exert an effect on bone mineral density. However, further large-scale studies are needed to corroborate this finding and investigate the potential underlying mechanisms involved.

Weak bones in diabetes mellitus – an update on pharmaceutical treatment options

Objectives

Diabetes mellitus is often associated with a number of complications such as nephropathy, neuropathy, retinopathy and foot ulcers. However, weak bone is a diabetic complication that is often overlooked. Although the exact mechanism for weak bones within diabetes mellitus is unclear, studies have shown that the mechanism does differ in both type I (T1DM) and type II diabetes (T2DM). This review, however, investigates the application of mesenchymal stem cells, recombinant human bone morphogenetic protein-2, teriparatide, insulin administration and the effectiveness of a peroxisome proliferator-activated receptor-ϒ modulator, netoglitazone in the context of diabetic weak bones.

Key findings

In T1DM, weak bones may be the result of defective osteoblast activity, the absence of insulin's anabolic effects on bone, the deregulation of the bone–pancreas negative feedback loop and advanced glycation end product (AGE) aggregation within the bone matrix as a result of hyperglycaemia. Interestingly, T2DM patients placed on insulin administration, thiazolidinediones, SGLT2 inhibitors and sulfonylureas have an associated increased fracture risk. T2DM patients are also observed to have high sclerostin levels that impair osteoblast gene transcription, AGE aggregation within bone, which compromises bone strength and a decrease in esRAGE concentration resulting in a negative association with vertebral fractures.

Summary

Effective treatment options for weak bones in the context of diabetes are currently lacking. There is certainly scope for discovery and development of novel agents that could alleviate this complication in diabetes patients.

Immunotherapy for type 1 diabetes

INTRODUCTION

Although many approaches have been tested to overcome the insulin dependence caused by the pancreatic β-cells destruction observed in individuals affected by type 1 diabetes (T1D), medical research has largely failed to halt the onset or to reverse T1D.

METHODS

In this work, the state of the art of immunotherapy will be examined, and the most important achievement in the field will be critically discussed. Particularly, we will focus on the clinical aspect, thus avoiding the tedious preclinical work done in NOD mice, which has been so poorly translated to the bedside.

CONCLUSIONS

Stem cell therapies achieved thus this far the most promising results, while immune ablation and standard immunosuppressants did not maintain the premises of preclinical results. The next step will be to generate a feasible and safe clinical approach in order to cure the thousands of patients affected by T1D.

Vitamin D and diabetes mellitus: Causal or casual association?

The incidence of both type 2 and type 1 diabetes mellitus has been increasing worldwide. Vitamin D deficiency, or the awareness of its prevalence, has also been increasing. Vitamin D may have a role in the pathogenic mechanisms predisposing to type 2 diabetes by modulating insulin resistance and/or pancreatic β-cell function. Vitamin D status or elements involved in its activation or transport may also be involved in the development of type 1 diabetes mellitus through immunomodulatory role . Based on these observations a potential association between vitamin D and diabetes has been hypothesized. In this review we discuss up to date evidence linking vitamin D with the development of diabetes. Moreover, the role of vitamin D supplementation in the prevention of both types of diabetes is analysed together with its role in improving glycemic control in diabetic patients. We also address the potential role of vitamin D deficiency in the development of macro- and microvascular complications in diabetes. Finally, we provide recommendation for Vitamin D therapy in diabetes in view of current evidence and highlight areas for potential future research in this area.

Diabetes and disordered bone metabolism (diabetic osteodystrophy): time for recognition

Diabetes and osteoporosis are rapidly growing diseases. The link between the high fracture incidence in diabetes as compared with the non-diabetic state has recently been recognized. While this review cannot cover every aspect of diabetic osteodystrophy, it attempts to incorporate current information from the First International Symposium on Diabetes and Bone presentations in Rome in 2014. Diabetes and osteoporosis are fast-growing diseases in the western world and are becoming a major problem in the emerging economic nations. Aging of populations worldwide will be responsible for an increased risk in the incidence of osteoporosis and diabetes. Furthermore, the economic burden due to complications of these diseases is enormous and will continue to increase unless public awareness of these diseases, the curbing of obesity, and cost-effective measures are instituted. The link between diabetes and fractures being more common in diabetics than non-diabetics has been widely recognized. At the same time, many questions remain regarding the underlying mechanisms for greater bone fragility in diabetic patients and the best approach to risk assessment and treatment to prevent fractures. Although it cannot cover every aspect of diabetic osteodystrophy, this review will attempt to incorporate current information particularly from the First International Symposium on Diabetes and Bone presentations in Rome in November 2014.

Update on Bone Health in Pediatric Chronic Disease

Children and adolescents with chronic disease are predisposed to impaired bone health. Pediatric illness, including type 1 diabetes mellitus, celiac disease, and cystic fibrosis, have significant risk of low bone mineralization and fracture due to underlying inflammation, malabsorption, lack of physical activity, and delayed puberty. Dual-energy x-ray absorptiometry is the primary imaging method to assess bone health in this population. The purpose of this review is to update readers about the assessment and management of bone health in children with common pediatric chronic illnesses and review recent advances in the prevention and treatment of impaired bone health.

MECHANISMS IN ENDOCRINOLOGY: Mechanisms and evaluation of bone fragility in type 1 diabetes mellitus

Subjects with type 1 diabetes mellitus (T1DM) have decreased bone mineral density and an up to sixfold increase in fracture risk. Yet bone fragility is not commonly regarded as another unique complication of diabetes. Both animals with experimentally induced insulin deficiency syndromes and patients with T1DM have impaired osteoblastic bone formation, with or without increased bone resorption. Insulin/IGF1 deficiency appears to be a major pathogenetic mechanism involved, along with glucose toxicity, marrow adiposity, inflammation, adipokine and other metabolic alterations that may all play a role on altering bone turnover. In turn, increasing physical activity in children with diabetes as well as good glycaemic control appears to provide some improvement of bone parameters, although robust clinical studies are still lacking. In this context, the role of osteoporosis drugs remains unknown.

2,3,5,4′-Tetrahydroxystilbene-2-O-β-d-glucoside exerted protective effects on diabetic nephropathy in mice with hyperglycemia induced by streptozotocin

This study demonstrated that the inhibition of the RAS with TSG effectively prevented renal injury in diabetic nephropathy.