Association of serum leptin with bone mineral density in postmenopausal osteoporotic females

Osteoprotegerin genetic polymorphisms and their influence on therapeutic response to ibandronate in postmenopausal osteoporotic females

OBJECTIVES

The present study investigated osteoprotegerin (OPG) genetic polymorphisms and their influence on the therapeutic response to ibandronate in postmenopausal osteoporotic females.

METHODS

This case-control study included 135 postmenopausal females (89 osteoporotic females and 46 non-osteoporotic females). Each osteoporotic patient received a monthly 150 mg ibandronate tablet for six months, and blood samples were taken before and after treatment. Bone mineral density (BMD) was measured using DEXA Scan. Three SNPs (A163G, T245G, and G1181C) of the OPG gene were selected for analysis.

RESULTS

Serum OPG levels were significantly lower in osteoporotic subjects than in the control group. The percentage changes in OPG levels in the osteoporotic group before and after treatment with ibandronate were significant (p < .001). After six months of therapy with ibandronate, the percentage changes in OPG levels with AA, TT, TC, GC, and GG genotypes were significant. Following six months of ibandronate treatment, the AA genotype of rs3134069, TT, TC genotypes of rs3102735, GG, and GC genotypes of rs2073618 SNP showed a significant increase in OPG levels. Age, BMI, and GC polymorphism (rs2073618 (G/C) G1181C) were inversely associated with low BMD. Adjusted odds ratios (OR) showed that BMI, GC, GG polymorphism (rs2073618 (G/C) G1181C) and TC polymorphism (rs3102735 (T/C) A163G) were inversely associated with low BMD.

CONCLUSION

The inverse association of rs2073618 and rs3102735 with low BMD indicates the protective role of these SNPs in our population. More research is needed to replicate these results in another cohort and to determine the molecular processes by which such SNPs may influence BMD.

Relationship between nonalcoholic fatty liver disease and bone mineral density in elderly Chinese

OBJECTIVE

As our society grows older, both bone loss and fatty liver have become important issues. However, the relationship between reduced bone mineral density and fatty liver remains controversial. The purpose of this study was to investigate the relationship between nonalcoholic fatty liver disease and less bone mineral density in the ankles of Chinese people over 65.

METHODS

The research included 716 older adults over the age of 65 who underwent a comprehensive health screening. A logistic regression model was used to investigate the relationship between nonalcoholic fatty liver disease (NAFLD) and ankle bone mineral density.

RESULTS

A logistic regression model was used to analyze the odds ratios of reduced bone mineral density between patients with fatty liver and controls. In the adjusted model, adjustments were made for age, sex, systolic blood pressure, diastolic blood pressure, overweight rate, history of hypertension, history of diabetes, history of smoking, history of alcohol consumption, fasting glucose, hemoglobin, urea, creatinine, triglycerides, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, waist circumference, total protein, albumin, and globulin. The adjusted OR (aOR) for reduced bone mineral density was 0.66 [95% confidence interval (CI) = 0.45-0.97, P = 0.034 < 0.05]. In subgroup analysis by age, sex, and BMI, women, age > 75 years, and BIM < 25 were statistically significant.

CONCLUSION

This study suggested that NAFLD is associated with a reduced risk of reduced heel bone mass. More research needs to be done to back up the results of this study and look into possible problems.

Analysis of gut microbiome composition, function, and phenotype in patients with osteoarthritis

Gut microbiome (GMB) disturbance can induce chronic low-grade inflammation, which is closely related to the occurrence and development of osteoarthritis (OA). However, the relationship between GMB and OA remains unclear. In this study, we collected stool samples from OA patients and healthy people, and performed Alpha diversity, Beta diversity, MetaStat, and LEfSe analysis by 16S rRNA sequencing to find out the species with significant difference between the two groups. Random forest analysis was performed to find out biomarkers that could distinguish between OA patients and healthy people. PICRUSt and Bugbase analysis were used to compare the difference in functions and phenotypes. Multivariate linear regression analysis (MaAsLin) was used to adjust for gender, age, and body mass index (BMI). The results showed that there was a significant difference in the overall composition of GMB between the two groups (p = 0.005). After adjusting for gender, age, and BMI, we found that p_Bacteroidota (Q = 0.039), c_Bacteroidia (Q = 0.039), and o_Bacteroidales (Q = 0.040) were enriched in the OA group, while s_Prevotella_copri (Q = 0.001) was enriched in the healthy control group. Prevotella could distinguish between OA patients and healthy people with a better diagnostic power (AUC = 77.5%, p < 0.001, 95% CI: 66.9-88.1%). The functions of DNA transcription, amino acid metabolism (including histidine, lysine, and isoleucine), ATP metabolism, and phospholipid metabolism significantly decreased, while glucose metabolism, protein acetylation, and aspartate kinase activity significantly increased in the OA group. In terms of phenotypes, we found that the relative abundance of aerobic (p = 0.003) and Gram-negative (p < 0.001) was higher in the OA group, while contains mobile elements (p = 0.001) and Gram-positive (p < 0.001) were higher in the healthy control group. Our study preliminarily demonstrated that there were differences in the composition, function, and phenotype of GMB in stool samples between OA patients and healthy people, which provided a novel perspective on further study in OA.

The Head-to-Toe Hormone: Leptin as an Extensive Modulator of Physiologic Systems

Leptin is a well-known hunger-sensing peptide hormone. The role of leptin in weight gain and metabolic homeostasis has been explored for the past two decades. In this review, we have tried to shed light upon the impact of leptin signaling on health and diseases. At low or moderate levels, this peptide hormone supports physiological roles, but at chronically higher doses exhibits detrimental effects on various systems. The untoward effects we observe with chronically higher levels of leptin are due to their receptor-mediated effect or due to leptin resistance and are not well studied. This review will help us in understanding the non-anorexic roles of leptin, including their contribution to the metabolism of various systems and inflammation. We will be able to get an alternative perspective regarding the physiological and pathological roles of this mysterious peptide hormone.

Association of serum chemerin with calcium, alkaline phosphatase and bone mineral density in postmenopausal females

Objectives:

To investigate the association of serum chemerin with calcium, alkaline phosphatase and bone mineral density in postmenopausal non-osteoporotic and osteoporotic females.

Methods:

This cross-section analysis was carried out at the orthopedic department of Madina Teaching Hospital, Faisalabad, Pakistan, in the year 2017-2019. Postmenopausal females were divided into two groups according to their bone mineral density (BMD). All osteoporotic females had a T-score of -2.5 or less. Data were analyzed on SPSS-24.

Results:

A total of 140 women were included in our study (80 osteoporotic and 60 non-osteoporotic). Non significant difference in age and BMI was observed between osteoporotic and non-osteoporotic subjects (p=0.152) and (p=0.291) respectively. There was a significant difference found in total BMD, serum chemerin levels between osteoporotic and non-osteoporotic subjects p<0.001 in both parameters. No significant correlation of serum chemerin was found with serum calcium, serum alkaline phosphatase and BMD in postmenopausal osteoporotic females (p=0.907), (p=0.318) (p=0.664) respectively. A significant negative correlation was found between serum alkaline phosphatase levels and total BMD in postmenopausal osteoporotic females (p=- 0.039). Linear regression analysis of serum alkaline phosphatase levels with total BMD showed no association between BMD and serum alkaline phosphatase levels (p=0.869).

Conclusion:

There is no association of serum chemerin with calcium, ALP and bone mineral density in non-osteoporotic and osteoporotic postmenopausal females.

Alkaline phosphatase is a predictor of Bone Mineral Density in postmenopausal females

Objectives:

The study was planned to determine whether serum calcium, phosphate and alkaline phosphatase (ALP) are predictors of bone mineral density (BMD) in postmenopausal non-osteoporotic, osteopenic, and osteoporotic females.

Methods:

In this cross sectional study, conducted at Shaikh Zayed Hospital, Lahore in the year 2014-2015, postmenopausal females between 50-70 years of age were taken and divided into three groups non-osteoporotic (n=52), osteopenic (n=69) and osteoporotic (n=47). Serum ALP, phosphate and calcium were used in a stepwise multiple regression analysis to predict T-score in these groups.

Results:

In normal postmenopausal females, the prediction model was statistically significant, F(2, 41) = 6.041, p < 0.05 and showed a T-score variance of 22%. T-score was primarily predicted by higher levels of phosphate and calcium. In postmenopausal osteopenic females, T-score was only predicted by lower levels of ALP. The model was statistically significant, F(1, 59) = 4.995, p < 0.05, and accounted for approximately 7% of the variance of T-score. In postmenopausal osteoporotic females, the prediction model contained no predictors.

Conclusion:

Our study suggested that calcium and phosphate are the strongest predictors of T-score in postmenopausal normal females, while in postmenopausal osteopenic females ALP was the strongest predictor of T-score. Elevated serum ALP levels may help in determining loss of BMD in postmenopausal females.

The Molecular Mechanism of Vitamin E as a Bone-Protecting Agent: A Review on Current Evidence

Bone remodelling is a tightly-coordinated and lifelong process of replacing old damaged bone with newly-synthesized healthy bone. In the bone remodelling cycle, bone resorption is coupled with bone formation to maintain the bone volume and microarchitecture. This process is a result of communication between bone cells (osteoclasts, osteoblasts, and osteocytes) with paracrine and endocrine regulators, such as cytokines, reactive oxygen species, growth factors, and hormones. The essential signalling pathways responsible for osteoclastic bone resorption and osteoblastic bone formation include the receptor activator of nuclear factor kappa-B (RANK)/receptor activator of nuclear factor kappa-B ligand (RANKL)/osteoprotegerin (OPG), Wnt/β-catenin, and oxidative stress signalling. The imbalance between bone formation and degradation, in favour of resorption, leads to the occurrence of osteoporosis. Intriguingly, vitamin E has been extensively reported for its anti-osteoporotic properties using various male and female animal models. Thus, understanding the underlying cellular and molecular mechanisms contributing to the skeletal action of vitamin E is vital to promote its use as a potential bone-protecting agent. This review aims to summarize the current evidence elucidating the molecular actions of vitamin E in regulating the bone remodelling cycle.

Identification of core genes and prediction of miRNAs associated with osteoporosis using a bioinformatics approach

Osteoporosis (OP) is an age-related disease, and osteoporotic fracture is one of the major causes of disability and mortality in elderly patients (>70 years old). As the pathogenesis and molecular mechanism of OP remain unclear, the identification of disease biomarkers is important for guiding research and providing therapeutic targets. In the present study, core genes and microRNAs (miRNAs) associated with OP were identified. Differentially expressed genes (DEGs) between human mesenchymal stem cell specimens from normal osseous tissues and OP tissues were detected using the GEO2R tool of the Gene Expression Omnibus database and Morpheus. Network topological parameters were determined using NetworkAnalyzer. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed using the Database for Annotation, Visualization and Integrated Discovery, and ClueGO. Cytoscape with the Search Tool for the Retrieval of Interacting Genes and Molecular Complex Detection plug-in was used to visualize protein-protein interactions (PPIs). Additionally, miRNA-gene regulatory modules were predicted using CyTargetLinker in order to guide future research. In total, 915 DEGs were identified, including 774 upregulated and 141 downregulated genes. Enriched GO terms and pathways were determined, including 'nervous system development', 'regulation of molecular function', 'glutamatergic synapse pathway' and 'pathways in cancer'. The node degrees of DEGs followed power-law distributions. A PPI network with 541 nodes and 1,431 edges was obtained. Overall, 3 important modules were identified from the PPI network. The following 10 genes were identified as core genes based on high degrees of connectivity: Albumin, PH domain leucine-rich repeat-containing protein phosphatase 2 (PHLPP2), DNA topoisomerase 2-α, kininogen 1 (KNG1), interleukin 2 (IL2), leucine-rich repeats and guanylate kinase domain containing, phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit γ (PIK3CG), leptin, transferrin and RNA polymerase II subunit A (POLR2A). Additionally, 15 miRNA-target interactions were obtained using CyTargetLinker. Overall, 7 miRNAs co-regulated IL2, 3 regulated PHLPP2, 3 regulated KNG1, 1 regulated PIK3CG and 1 modulated POLR2A. These results indicate potential biomarkers in the pathogenesis of OP and therapeutic targets.

Interplay of vitamin D, vitamin B12, homocysteine and bone mineral density in postmenopausal females

Osteoporosis is most common age related, multifactorial disease. The aim of the researchers were to discover the association between serum homocysteine, vitamin D, vitamin B₁₂ and bone mineral density in postmenopausal non-osteoporotic and osteoporotic females. In this cross- sectional study, 156 postmenopausal females between 50-70 years of age were recruited and divided into two groups, non-osteoporotic (n = 52) and osteoporotic (n = 104). There was significant negative correlation of homocysteine with vitamin D and B₁₂ in postmenopausal non-osteoporotic and homocysteine with vitamin B₁₂ in postmenopausal osteoporotic females. Serum homocysteine levels were predicted by vitamin D in postmenopausal non-osteoporotic and vitamin B₁₂ in postmenopausal osteoporotic females.