The polymorphism of Insulin-like growth factor-I (IGF-I) is related to osteoporosis and bone mineral density in postmenopausal population

Association of the GHRd3 polymorphism with adult height and type 2 diabetes in a Saudi Arabian population from Jazan Province: A case-control study

Objectives

This study investigated the association of the GHRd3 polymorphism with height and type-2 diabetes mellitus (T2DM) in Saudi Arabia.

Methods

This case-control study included a total of 284 participants, divided into healthy controls (n = 142) and patients with T2DM (n = 142), recruited from Jazan University Hospital, southwest of Saudi Arabia in the period between January to September 2022. The GHRd3 polymorphism was genotyped using multiplex PCR. The correlation between height and genotypes was analyzed using one-way analysis of variance. The association between GHRd3 polymorphism and T2DM was assessed using logistic regression analysis.

Results

The data showed a significant difference between the means of heights associated with each GHRd3 genotype, flfl, fld3, and d3d3. Logistic regression analysis showed no association between GHRd3 variants and T2DM.

Conclusion

Homozygous GHRd3 polymorphism carriers, d3d3 genotype, were taller than fld3 or flfl carriers in our population. None of the GHRd3 variants were associated with T2DM. Thus, the GHRd3 polymorphism has growth-related actions with a minor contribution to T2DM. However, more studies with a larger sample size are required to confirm these findings.

A case-control study coupling with meta-analysis elaborates decisive association between IGF-1 rs35767 and osteoporosis in Asian postmenopausal females

BACKGROUND

Osteoporosis (OP) is prevalent in postmenopausal women. Several studies investigated the association between IGF-1 polymorphisms and OP among postmenopausal females with conflicting outcomes.

OBJECTIVE

To investigate whether the IGF-1 (rs35767, rs2288377, rs5742612) were associated with OP in postmenopausal females.

METHODS

In case-control study, 95 OP cases and 222 healthy controls were recruited between March 2015 and July 2019. OP was diagnosed based on WHO criteria for diagnosis of OP as T score of bone mineral density (BMD) ≤-2.5; normal, as T score of BMD ≥-1. IGF-1 SNPs were genotyped by iPLEX Gold SNP genotyping. To be solid, related studies from PubMed, Embase, Cochrane, Web of science, and previous meta-analysis up until November 2020, along with our case-control study, were incorporated into a meta-analysis with criteria of significance using odds ratios (ORs) with corresponding 95% confidence intervals (CI) to evaluate risk factor of SNPs on OP. TSA was used to estimate the sample sizes required to achieve a conclusion.

RESULTS

In dominant model of our case-control study, we found nonsignificant association of rs35767 [Adj-OR: 0.95 (95% CI: 0.56-1.60)], rs2288377 [Adj-OR: 1.15 (95% CI: 0.67-1.97)], and rs5742612 [Adj-OR: 1.07 (95% CI: 0.62-1.83)] with OP in postmenopausal females. However, integration of our case-control study and 3 published studies, rs35767 [OR: 1.24 (95% CI: 1.05-1.47)] showed a conclusively risk association with OP in postmenopausal females judged by TSA with 2267 Asians.

CONCLUSIONS

This study demonstrates a crucial sample to conclude that IGF-1 rs35767 is significantly associated with OP in postmenopausal women.

Unveiling the transcriptomic landscape and the potential antagonist feedback mechanisms of TGF-β superfamily signaling module in bone and osteoporosis

BACKGROUND

TGF-β superfamily signaling is indispensable for bone homeostasis. However, the global expression profiles of all the genes that make up this signaling module in bone and bone-related diseases have not yet been well characterized.

METHODS

Transcriptomic datasets from human bone marrows, bone marrow-derived mesenchymal stem cells (MSCs) and MSCs of primary osteoporotic patients were used for expression profile analyses. Protein treatments, gene quantification, reporter assay and signaling dissection in MSC lines were used to clarify the interactive regulations and feedback mechanisms between TGF-β superfamily ligands and antagonists. Ingenuity Pathway Analysis was used for network construction.

RESULTS

We identified TGFB1 in the ligand group that carries out SMAD2/3 signaling and BMP8A, BMP8B and BMP2 in the ligand group that conducts SMAD1/5/8 signaling have relatively high expression levels in normal bone marrows and MSCs. Among 16 antagonist genes, the dominantly expressed TGF-β superfamily ligands induced only NOG, GREM1 and GREM2 via different SMAD pathways in MSCs. These induced antagonist proteins further showed distinct antagonisms to the treated ligands and thus would make up complicated negative feedback networks in bone. We further identified TGF-β superfamily signaling is enriched in MSCs of primary osteoporosis. Enhanced expression of the genes mediating TGF-β-mediated SMAD3 signaling and the genes encoding TGF-β superfamily antagonists served as significant features to osteoporosis.

CONCLUSION

Our data for the first time unveiled the transcription landscape of all the genes that make up TGF-β superfamily signaling module in bone. The feedback mechanisms and regulatory network prediction of antagonists provided novel hints to treat osteoporosis. Video Abstract.

Sarcopenia and bone health: new acquisitions for a firm liaison

Osteosarcopenia (OS) is a newly defined condition represented by the simultaneous presence of osteopenia/osteoporosis and sarcopenia, the main age-related diseases. The simultaneous coexistence of the two phenotypes derives from the close connection of the main target tissues involved in their pathogenesis: bone and muscle. These two actors constitute the bone-muscle unit, which communicates through a biochemical and mechanical crosstalk which involves multiple factors. Altered pattern of molecular pathways leads to an impairment of both the functionality of the tissue itself and the communication with the complementary tissue, composing the OS pathogenesis. Recent advances in the genetics field have provided the opportunity to delve deeper into the complex biological and molecular mechanisms underlying OS. Unfortunately, there are still many gaps in our understanding of these pathways, but it has proven essential to apply strategies such as exercise and nutritional intervention to counteract OS. New therapeutic strategies that simultaneously target bone and muscle tissue are limited, but recently new targets for the development of dual-action drug therapies have been identified. This narrative review aims to provide an overview of the latest scientific evidence associated with OS, a complex disorder that will pave the way for future research aimed at understanding the bone-muscle-associated pathogenetic mechanisms.

MiR-26a regulates the expression of serum IGF-1 in patients with osteoporosis and its effect on proliferation and apoptosis of mouse chondrocytes

OBJECTIVES

To examine the effects of the regulation on IGF-1 by miR-26a on the serum of patients with osteoporosis (OP) and apoptosis and proliferation of chondrocytes of mice with OP.

METHODS

Totally 47 patients with OP treated in our hospital between July 2018 and November 2019 were selected as the research group, and 42 healthy individuals in physical examination over this period were selected as the control group. Serum was sampled from each participant in both groups, and miR-26a in the sampled serum was quantified and compared. In addition, chondrocytes were sampled from mice with OP. The changes of proliferation and apoptosis of the chondrocytes were analyzed via MTT and flow cytometry, and the levels of Caspase3, Caspase9, Bax, and Bcl-2 were quantified by western blot (WB) assay.

RESULTS

MiR-26a was expressed highly in the serum of patients with OP and chondrocytes of mice with OP, while IGF-1 was lowly expressed in them. According to the dual-luciferase reporter assay, there was a targeting correlation between miR-26a and IGF-1, and suppressing miR-26a significantly up-regulated the expression and protein level of IGF-1.

CONCLUSIONS

MiR-26a can serve as a biological marker for the diagnosis of OP, and it can suppress the proliferation of chondrocytes and promote their apoptosis by regulating IGF-1.

Effect of enhanced masticatory force on OPG, RANKL and MGF in alveolar bone of ovariectomized rats

BACKGROUND

Menopause induces oral bone loss, leading to various oral diseases. Mastication importantly affects bone metabolism in the jawbone.

OBJECTIVE

To analyze the effect of enhanced masticatory force on osteoprotegerin (OPG), receptor activator of nuclear factor kappa B ligand (RANKL), and mechano-growth factor (MGF) in alveolar bone of ovariectomized rats and to study the mechanics mechanism of the alveolar bone of ovariectomized rats response to enhanced masticatory force.

METHODOLOGY

Thirty Sprague Dawley rats were randomly divided into three groups: sham-operation group (fat around the removed ovary + normal hard diet), model group (ovariectomy + normal hard diet), and experimental group (ovariectomy + high hard diet). It was a 2-month experiment. Enzyme-linked immunosorbent assay (ELISA) detected serum estradiol (E2), osteocalcin (BGP) and alkaline phosphatase (ALP) in rats. Bone histomorphometric indices in the third molar region of maxilla were detected by micro-CT; protein expressions of OPG, RANKL, and MGF in the third molar region of maxilla was detected by Western blot; and gene expression of OPG, RANKL, and MGF in the third molar region of maxilla was detected by Quantitative Real-Time PCR.

RESULTS

Comparing with model group, serum E2 in experimental group increased but not significantly, serum BGP and serum ALP in experimental group decreased but not significantly, OPG in experimental group in alveolar bone increased significantly, RANKL in experimental group in alveolar bone decreased significantly, RANKL/OPG ratio in experimental group decreased significantly, MGF in experimental group in alveolar bone increased significantly, bone volume to total volume fraction increased significantly in experimental group, trabecular thickness increased significantly in experimental group, and trabecular separation decreased significantly in experimental group.

CONCLUSION

Enhanced masticatory force affected the expression of OPG, RANKL, and MGF in alveolar bone of ovariectomized rats, improved the quality of jaw bone of ovariectomized rats, and delayed oral bone loss by ovariectomy.

Associations of IDUA and PTCH1 with Bone Mineral Density, Bone Turnover Markers, and Fractures in Chinese Elderly Patients with Osteoporosis

Introduction

Osteoporosis (OP) is a common polygenic disorder in the aging population, and several single nucleotide polymorphisms (SNPs) in the alpha-L-iduronidase (IDUA) gene and patched homolog 1 (PTCH1) gene regulate bone metabolism and affect bone mass. The study aimed at investigating the relationships of rs3755955 and rs6831280 in the IDUA gene and rs28377268 in the PTCH1 gene with bone mineral density (BMD), bone turnover markers (BTMs), and fractures in the elderly Chinese subjects with OP.

Materials and Methods

A cohort of 328 unrelated senile osteoporosis (SOP) patients with or without osteoporotic fractures was recruited. rs3755955, rs6831280, and rs28377268 polymorphisms were identified using SNaPshot technology. BTM levels were determined by electrochemiluminescence (ECL). Bone mineral densities (BMDs) at the lumbar spine (LS) and proximal femur sites were measured by dual-energy X-ray absorptiometry (DEXA) in all subjects. The Hardy-Weinberg equilibrium (HWE) test was performed. HWE P values and comparisons of genotype frequencies were estimated using the chi-square test. Analysis of covariance (ANCOVA) adjusted for confounding factors was performed to investigate associations of SNPs with BMDs and BTMs in subgroups.

Results

The chi-square test indicated that genotype distributions in the control group conformed to HWE (P > 0.05). The distributions of allele and genotype frequencies of rs6831280 between fracture and osteoporotic participants were significantly different (P-allele = 0.002 and P-genotype = 0.012, respectively). Concerning rs6831280, ANCOVA found BMDs at LS 2-4 (L2-4) and total hip (TH) among the study subjects suffering from SOP with GA genotype were lower than in those carrying GG or AA (P-L2-4 = 0.004 and P-TH = 0.027, respectively).

Conclusions

IDUA rs6831280 is associated with BMDs at L2-4 and TH in the elderly Chinese population with SOP and may serve as a marker for the genetic susceptibility to osteoporotic fractures.

Association between IGF-1 polymorphisms and risk of osteoporosis in Chinese population: a meta-analysis

Background

Several studies looking into the association between insulin-like growth factor-1 (IGF-1) gene polymorphisms and osteoporosis predisposition have been conducted among Chinese population with conflicting outcomes. The present systematic review and meta-analysis was performed to appraise and synthesize the existing evidence, so as to provide a more precise and reliable association between polymorphisms in IGF-1 gene and osteoporosis.

Methods

Five electronic databases including PubMed, EMBASE, ISI Web of Science, CNKI and Wanfang were systematically searched for potential studies. Summary odds ratio (OR) and corresponding 95% confidence interval (95% CI) were calculated to evaluate the association. The best-matching genetic model of inheritance was determined using a genetic-model free approach.

Results

Six case-control studies comprising 2068 osteoporosis patients and 2071 healthy controls were obtained for the meta-analysis. Dominant model was confirmed to be the best-matching genetic model (TT + TC versus CC). The overall data suggested that rs35767 polymorphism was significantly associated with osteoporosis vulnerability (OR 1.21, 95% CI 1.07, 1.37; P = 0.002). When stratifying the participants and performing subgroup-analysis according to source of patients, the result suggested that rs35767 was significantly correlated to osteoporosis in post-menopausal women subgroup (OR 1.29, 95% CI 1.08, 1.54; P = 0.005), but the correlation was not established in the subgroup of both gender (OR 1.14, 95% CI 0.96, 1.35; P = 0.12).

Conclusion

Taken together, the findings of our current study suggested a significant association between rs35767 polymorphism and risk of osteoporosis in Chinese post-menopausal women.

Electronic supplementary material

The online version of this article (10.1186/s12891-018-2066-y) contains supplementary material, which is available to authorized users.

Association of insulin-like growth factor I gene polymorphisms with the risk of osteoporosis in a Chinese population

Osteoporosis is a systemic metabolic and serious skeletal disease commonly observed among the elderly. Insulin-like growth factors (IGFs) are critical regulators for bone cell function. We estimated the role of IGF-I rs35767, rs2288377 and rs5742612 polymorphisms in the susceptibility to osteoporosis in a population of China, and assessed gene-environment interactions. A total of 346 patients with osteoporosis and 346 controls were enrolled. Genotyping of IGF-I rs35767, rs2288377 and rs5742612 was amplified and performed with the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The TA and AA genotypes displayed elevated risk of developing osteoporosis (TA vs TT: OR=1.54, 95% CI=1.11-2.15; AA vs TT: OR=3.65, 95% CI=2.09-6.37). Compared with TT individuals, individuals with the TA+AA genotype had a substantial increased susceptibility to osteoporosis (OR=1.80, 95% CI=1.31-2.46). In recessive model, the AA genotype of rs2288377 displayed 2.89 folds risk of osteoporosis (adjusted OR=2.89, 95% CI=1.70-4.89). A significant negative interaction was found between IGF-I rs2288377 and BMD levels for femoral neck (r=-0.14, P<0.001), total hip (r=-0.09, P<0.001) and trochanter (r=-0.13, P<0.001). In conclusion, we suggest that IGF-I rs2288377 polymorphism had a strong influence on osteoporosis susceptibility in this Chinese population.

Systematic analysis of lncRNAs, miRNAs and mRNAs for the identification of biomarkers for osteoporosis in the mandible of ovariectomized mice

Osteoporosis is a complex and multifactorial disease caused by an imbalance between bone formation and resorption. Post-menopausal women with endogenous estrogen deficiency suffer from systemic bone loss and osteoporosis, and are at high risk of this affecting the jaw bones. MicroRNAs (miRNAs or miRs) have been implicated in the mechanisms of metabolic bone diseases and are expressed at differential levels in alveolar bone following ovariectomy. In the present study, we systematically analyzed the expression profiles of miRNAs, mRNAs and long non-coding RNA (lncRNAs) in the mandible of ovariectomized (OVX) mice. A complex miRNA-mRNA-lncRNA regulatory network was constructed based on differentially expressed RNAs. Two core differentially expressed genes (DEGs), namely, LRP2 binding protein (Lrp2bp) and perilipin 4 (Plin4), significantly influenced the network targeted by differentially expressed miRNAs. Moreover, peroxisome proliferator-activated receptor (PPAR) and insulin signaling pathways were significantly dysregulated in the mandible of OVX mice. Several differentially expressed lncRNAs were also implicated in the two signaling pathways, which influenced mandible development by forming competing endogenous RNA. On the whole, our data indicate that the comprehensive analysis of miRNAs, mRNAs and lncRNAs provides insight into the pathogenesis of estrogen deficiency-induced osteoporosis in the mandible. This study proposes potential biomarkers for diagnosis or therapeutic targets for osteoporosis which may aid in the development of novel drugs for the treatment of osteoporosis.

Influence of polymorphisms in insulin-like growth factor-1 on the risk of osteoporosis in a Chinese postmenopausal female population

We conducted a case-control study in a Chinese postmenopausal population, and explore the potential role of the promoter region variation of the IGF-1 gene in bone mineral density and osteoporosis risk. 485 postmenopausal women with a primary diagnosis of osteoporosis and 485 age-matched controls were selected between 2012 and 2014. The Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) was used for rs35767, rs2288377 and rs5742612 of IGF-1 genotyping. By conditional regression analysis, individuals carrying TT genotype and CT+TT genotype of rs35767 were found to be correlated with an elevated risk of osteoporosis, with adjusted ORs (95% CI) of 1.90 (1.23-2.93) and 1.35 (1.04-1.76), respectively. Our study found that CT+TT genotype of rs35767 was significantly associated with moderate increased risk of osteoporosis in smokers and drinkers, and the ORs (95% CI) were 2.11 (1.06-4.20) and 2.36 (1.29-4.32), respectively. We found that those carrying CT+TT genotype of rs35767 had a significant lower BMD levels at L1-L4 vertebrae, femoral neck, total hip and trochanter compared to those with CC genotype. Our study suggests that TT genotype and CT+TT genotype of IGF-I rs35767 were associated with risk of osteoporosis and BMD levels.