Metaanalysis Reveals Genetic Correlates of Osteoporosis Pathogenesis

Pharmacogenetics of Response to Bisphosphonate Treatment in Postmenopausal Osteoporosis: A Prospective Study

BACKGROUND

This study aims to investigate the effect of genetic polymorphisms of vitamin D receptor (VDR), estrogen receptor 1 (ER1), and Col1a1 on the response to bisphosphonate (BP) therapy in women with postmenopausal osteoporosis (OP).

METHODS

Twenty-one women with postmenopausal OP who received alendronate, ibandronate, or zoledronic acid for one year were enrolled in this study. Bone mineral density (BMD) at the lumbar spine and femoral neck were assessed by dual energy X-ray absorptiometry at baseline and after 12 months. Serum osteocalcin levels were measured at baseline and after 12 months. Polymorphic sites of the genes encoding ER1, VDR and Col1a1 proteins were amplified by polymerase chain reaction and examined using restriction fragment length polymorphism. Response to BP treatment and change in osteocalcin levels were compared among women with different gene polymorphisms.

RESULTS

Ratio of responders to treatment regarding improvements in the BMD of lumbar spine and femoral neck was adequate in 76% and 62%, respectively. There was no significant difference in treatment response regarding BMD in either region or change in serum osteocalcin levels among different gene polymorphisms.

CONCLUSIONS

These findings did not support the potential role of VDR BsmI, Col1a1 Sp1, ER1 PvuII, or XbaI polymorphisms in predicting the response to BP therapy in women with postmenopausal OP. Further investigation with larger prospective studies is required.

Palm Tocotrienol Activates the Wnt3a/β-Catenin Signaling Pathway, Protecting MC3T3-E1 Osteoblasts from Cellular Damage Caused by Dexamethasone and Promoting Bone Formation

Background and aim: Prolonged glucocorticoid (GC) treatment increases oxidative stress, triggers apoptosis of osteoblasts, and contributes to osteoporosis. Tocotrienol, as an antioxidant, could protect the osteoblasts and preserve bone quality under glucocorticoid treatment. From this study, we aimed to determine the effects of tocotrienol on MC3T3-E1 murine pre-osteoblastic cells treated with GC. Methods: MC3T3-E1 cells were exposed to dexamethasone (150 µM), with or without palm tocotrienol (PTT; 0.25, 0.5, and 1 µg/mL). Cell viability was measured by the MTS assay. Alizarin Red staining was performed to detect calcium deposits. Cellular alkaline phosphatase activity was measured to evaluate osteogenic activity. The expression of osteoblastic differentiation markers was measured by an enzyme-linked immunoassay. Results: Enhanced matrix mineralization was observed in the cells treated with 0.5 µg/mL PTT, especially on day 18 (p < 0.05). The expression of Wnt3a, β-catenin, collagen 1α1, alkaline phosphatase, osteocalcin, low-density lipoprotein receptor-related protein 6, and runt-related transcription factor-2 were significantly increased in the PTT-treated groups compared to the vehicle control group, especially at 0.5 µg/mL of PTT (p < 0.05) and on day 6 of treatment. Conclusions: PTT maintains the osteogenic activity of the dexamethasone-treated osteoblasts by promoting their differentiation.

Exploring the Mechanisms of Sanguinarine in the Treatment of Osteoporosis by Integrating Network Pharmacology Analysis and Deep Learning Technology

BACKGROUND

Sanguinarine (SAN) has been reported to have antioxidant, antiinflammatory, and antimicrobial activities with potential for the treatment of osteoporosis (OP).

OBJECTIVE

This work purposed to unravel the molecular mechanisms of SAN in the treatment of OP.

METHODS

OP-related genes and SAN-related targets were predicted from public databases. Differential expression analysis and VennDiagram were adopted to detect SAN-related targets against OP. Protein-protein interaction (PPI) network was served for core target identification. Molecular docking and DeepPurpose algorithm were further adopted to investigate the binding ability between core targets and SAN. Gene pathway scoring of these targets was calculated utilizing gene set variation analysis (GSVA). Finally, we explored the effect of SAN on the expressions of core targets in preosteoblastic MC3T3-E1 cells.

RESULTS

A total of 21 candidate targets of SAN against OP were acquired. Furthermore, six core targets were identified, among which CASP3, CTNNB1, and ERBB2 were remarkably differentially expressed in OP and healthy individuals. The binding energies of SAN with CASP3, CTNNB1, and ERBB2 were -6, -6.731, and -7.162 kcal/mol, respectively. Moreover, the GSVA scores of the Wnt/calcium signaling pathway were significantly lower in OP cases than in healthy individuals. In addition, the expression of CASP3 was positively associated with Wnt/calcium signaling pathway. CASP3 and ERBB2 were significantly lower expressed in SAN group than in DMSO group, whereas the expression of CTNNB1 was in contrast.

CONCLUSION

CASP3, CTNNB1, and ERBB2 emerge as potential targets of SAN in OP prevention and treatment.

Quinoa alleviates osteoporosis in ovariectomized rats by regulating gut microbiota imbalance

BACKGROUND

Postmenopausal osteoporosis (PMO) is associated with dysregulation of bone metabolism and gut microbiota. Quinoa is a grain with high nutritional value, and its effects and potential mechanisms on PMO have not been reported yet. Therefore, the purpose of this study is to investigate the bone protective effect of quinoa on ovariectomy (OVX) rats by regulating bone metabolism and gut microbiota.

RESULTS

Quinoa significantly improved osteoporosis-related biochemical parameters of OVX rats and ameliorated ovariectomy-induced bone density reduction and trabecular structure damage. Quinoa intervention may repair the intestinal barrier by upregulating the expression of tight junction proteins in the duodenum. In addition, quinoa increased the levels of Firmicutes, and decreased the levels of Bacteroidetes and Prevotella, reversing the dysregulation of the gut microbiota. This may be related to estrogen signaling pathway, secondary and primary bile acid biosynthesis, benzoate degradation, synthesis and degradation of ketone bodies, NOD-like receptor signaling pathway and biosynthesis of tropane, piperidine and pyridine alkaloids. Correlation analysis showed that there is a strong correlation between gut microbiota with significant changes in abundance and parameters related to osteoporosis.

CONCLUSION

Quinoa could significantly reverse the high intestinal permeability and change the composition of gut microbiota in OVX rats, thereby improving bone microstructure deterioration and bone metabolism disorder, and ultimately protecting the bone loss of OVX rats. © 2024 Society of Chemical Industry.

Clinical challenges and considerations in pharmacotherapy of osteoporosis due to menopause

INTRODUCTION

Osteoporosis is a chronic systemic skeletal disorder characterized by compromised bone strength and an increased risk of fracture, with a high prevalence worldwide. It is associated with a negative quality of life and an increased morbidity and mortality. Postmenopausal women are more prone to develop osteoporosis, and many of them will suffer at least one fragility fracture along their lifetime.

AREAS COVERED

This review starts by summarizing the pathogenesis of postmenopausal osteoporosis (PMO), with focus on the estrogen deficiency-associated bone loss. It continues with the current PMO diagnostic and fracture risk prediction tools, and it finally addresses management of PMO. All the efficacy and safety profiles of the current and future osteoporosis medications are reviewed. Furthermore, strategies to optimize the long-term disease management are discussed. For this review, only publications in English language were selected. References were extracted from PubMed, Embase, and Medline.

EXPERT OPINION

PMO disease management is far from being ideal. Educational and communication programs with the goal of improving disease knowledge and awareness, as well as reducing the health-care gap, should be implemented. In addition, most effective sequential prevention and treatment strategies should be initiated from the early menopause.

Skeletal abnormalities, pediatric-onset severe osteoporosis, and multiple fragility fractures in a patient with a novel CTNNB1 de novo variant

We report a case of a patient with a de novo germline heterozygous truncating variant of CTNNB1 gene (c.2172del, p.Tyr724Ter) causing neurodevelopmental disorder with spastic diplegia and visual defects syndrome (NEDSDV) associated with a new clinical feature - severe pediatric-onset osteoporosis and multiple fractures. A functional effect of the identified variant was demonstrated using adipose-tissue derived primary mesenchymal stem cells, where we detected the alteration of CTNNB1mRNA and β-catenin protein levels using real-time PCR and Western blot analysis.

Decoding the mechanism of Eleutheroside E in treating osteoporosis via network pharmacological analysis and molecular docking of osteoclast-related genes and gut microbiota

Objective

Eleutheroside E (EE) is an anti-inflammatory natural compound derived from the edible medicinal herb Acanthopanax senticosus. This study aims to investigate the underlying mechanism of the anti-osteoporosis action of EE through network pharmacology, molecular docking and gut microbiota.

Materials and methods

Network pharmacology was used to explore the potential core targets and main pathways mediated by EE in osteoporosis (OP) treatment. Molecular docking was exploited to investigate the interactions between the active anti-OP compounds in EE and the potential downstream targets. Following the multi-approach bioinformatics analysis, ovariectomy (OVX) model was also established to investigate the in vivo anti-OP effects of EE.

Results

The top 10 core targets in PPI network were TP53, AKT1, JUN, CTNNB1, STAT3, HIF1A, EP300, CREB1, IL1B and ESR1. Molecular docking results that the binding energy of target proteins and the active compounds was approximately between -5.0 and -7.0 kcal/mol, which EE has the lowest docking binding energy with HIF1A. Enrichment analysis of GO and KEGG pathways of target proteins indicated that EE treatment could potentially alter numerous biological processes and cellular pathways. In vivo experiments demonstrated the protective effect of EE treatment against accelerated bone loss, where reduced serum levels of TRAP, CTX, TNF-α, LPS, and IL-6 and increased bone volume and serum levels of P1NP were observed in EE-treated mice. In addition, changes in gut microbiota were spotted by 16S rRNA gene sequencing, showing that EE treatment increased the relative abundance of Lactobacillus and decreased the relative abundance of Clostridiaceae.

Conclusion

In summary, these findings suggested that the characteristics of multi-target and multi-pathway of EE against OP. In vivo, EE prevents the onset of OP by regulating gut microbiota and inflammatory response and is therefore a potential OP drug.

Clinical description and genetic analysis of a novel familial skeletal dysplasia characterized by high bone mass and lucent bone lesions

High bone mass (HBM) disorders are a clinically and genetically heterogeneous subgroup of rare skeletal dysplasias. Here we present a case of a previously unreported familial skeletal dysplasia characterized by HBM and lucent bone lesions that we aimed to clinically characterize and genetically investigate. For phenotyping, we reviewed past clinical records and imaging tests, and performed physical examination (PE), bone densitometry, and mineral panels in affected individuals, including a male proband, his son and daughter, in addition to unaffected controls, including the proband's wife and brother. Affected individuals also underwent impact microindentation (IMI). In an effort to elucidate the disorder's molecular etiology, whole exome sequencing (WES) was performed in all individuals to filter for rare variants present only in affected ones. The cases displayed a unique skeletal phenotype with a mix of sclerotic features and lucent bone lesions, and high IMI values. Bone mineral density was very elevated in the proband and his daughter. The proband's daughter also exhibited idiopathic scoliosis (IS), in addition to mild thrombocytopenia and mild structural thyroid abnormalities, which were the only extra-skeletal abnormalities identified. WES analysis yielded 5 rare putative pathogenic variants in affected members in genes that are associated with bone metabolism including: SEM4AD, TBX18, PTCH1, PTK7, and ADGRE5. The PTK7 variant appeared as possibly implicated in the development of IS while the TBX18 and SEMA4D variants stood out as the strongest candidates for the lucent bone lesions and HBM, respectively, given their high predicted pathogenicity and putative role in bone biology. Variant functionality should be addressed in the future to assess their implication in skeletal metabolism as it is the first time that mutations in TBX18 and SEMA4D have been associated to bone developmental lesions and mineral metabolism in a clinical setting.