From Cells to Environment: Exploring the Interplay between Factors Shaping Bone Health and Disease

miR-374-5p inhibits osteogenesis by targeting PTEN/PI3K/AKT signaling pathway

PURPOSE

This study aims to evaluate the effects of miR-374-5p on osteogenesis in rat osteoblasts, validate its target on PTEN, and explore its role in the PTEN/PI3K/AKT signaling pathway during osteoblast differentiation.

METHODS

We transfected 293T cells with miR-374-5p mimics and inhibitors, followed by Western blot and qRT-PCR analyses to assess protein and mRNA expression levels. A dual-luciferase assay was performed to confirm direct targeting. Markers of osteoblast function, such as Runx2, OSX, and OCN, were examined in osteoblasts from rats by qRT-PCR and Western blot. Additionally, we developed a lentiviral vector to overexpress miR-374-5p, which successfully infected rat osteoblast progenitors. Bone formation was subsequently assessed using Alizarin Red staining and ALP activity assays. Finally, rescue experiments were conducted to validate the involvement of the miR-374-5p/PTEN/PI3K/AKT signaling pathway.

RESULTS

Our results demonstrate that miR-374-5p significantly downregulates both the protein and mRNA levels of its target gene PTEN, as confirmed by dual luciferase assays. qRT-PCR and Western blot analyses revealed that osteoblastic markers-including Runx2, OSX, and OCN-were markedly reduced in the miR-374-5p mimic group, whereas an opposite trend was observed in the inhibitor group. In vitro, overexpression of miR-374-5p suppressed osteoblast differentiation, as evidenced by decreased calcium nodule formation and reduced ALP activity compared to controls. Furthermore, co-transfection of miR-374-5p mimics with the PI3K/AKT pathway inhibitor LY294002 in osteoblasts led to significantly lower expression of PI3K/AKT pathway-related genes, and notably, the inhibitory effect of miR-374-5p on osteoblast differentiation was reversed by LY294002 treatment.

CONCLUSION

Our findings indicate that miR-374-5p inhibits osteogenesis in rat osteoblasts by targeting PTEN and modulating the PI3K/AKT signaling pathway.

The Impact of Fermented Dairy Products and Probiotics on Bone Health Improvement

The bone is an important body organ due to its role in locomotion, protection and mineral homeostasis. Bone health is affected by various intrinsic and extrinsic factors like genetics, diet, environment and immune status of an individual. Being a dynamic organ, bones are continuously being remodeled and the remodeling is mediated by an intricate balance of bone formation and resorption which, in turn, are regulated by environmental, genetic, hormonal and neural factors. Lack of balance in any of these factors leads to bone disorders such as osteoporosis. Fermented dairy products along with their probiotics content play a significant role in bone remodeling process ensuring the maintenance of intricate balance in bone forming cells (osteoblasts) and bone resorbing cells (osteoclasts). Proteins and various minerals are important constituents of bone. Dairy products, especially fermented ones, are significant because of being a good source of proteins and minerals required to make and maintain a healthy bone. In addition, these provide the body with probiotics which are involved in bone health improvement by enhancing the bioavailability of dietary constituents, production of short chain fatty acids and reducing the inflammatory components. Hence, fermented dairy products should be a regular part of our diet to keep our bone healthy.

A Study on the Prevalence of Osteoporosis in People with Different Altitudes in Sichuan, China

Purpose

Osteoporosis is a major health concern among the elderly, underscoring the importance of investigating its prevalence across different geographical regions. There is a current research gap regarding the incidence of osteoporosis and its variation by altitude within Sichuan, China. This study aimed to assess the prevalence of osteoporosis among populations residing at different altitudes in western Sichuan Province.

Basic Procedures

This study utilized data from a population-based cohort in Sichuan, China. Representative locations were selected, and cluster random sampling was employed to conduct cohort studies across multiple sites in southwestern China. T Baseline data were collected from populations in Mianzhu, Kangting, and Sertar between July 2020 and August 2021. To assess differences in osteoporosis incidence among populations at different altitudes and with varying characteristics, we applied Chi-square and rank-sum tests.

Main Findings

The study involved 4074 participants, including 1404 males (34.46%) and 791 individuals diagnosed with osteoporosis (19.42%). The prevalence of osteopenia in mid-altitude and high-altitude regions was 20.05% and 16.28%, respectively, while the prevalence of osteoporosis was significantly different, at 25.85% in mid-altitude areas compared to 13.00% in high-altitude areas (P < 0.001). Further analysis identified statistically significant differences in the prevalence of osteopenia and osteoporosis among females (P<0.001), middle-aged (P=0.015) and elderly populations (P=0.038), as well as among individuals who were underweight (P=0.011), normal weight (P<0.001), overweight (P<0.001), and obese (P=0.038). As altitude increased, the prevalence of osteoporosis decreased in all groups except the elderly, while the prevalence of osteopenia decreased among women and across various BMI categories, but increased among middle-aged and elderly individuals. Additionally, in high-altitude regions, Kangting recorded an 18.10% prevalence of osteopenia and a 14.26% prevalence of osteoporosis, compared to Sertar, which exhibited a 6.54% prevalence of osteopenia and a 6.23% prevalence of osteoporosis, indicating significant differences (P<0.001).

Conclusion

This study demonstrates that higher altitudes are associated with a decreased prevalence of osteopenia and osteoporosis, particularly among females and middle-aged individuals. These results emphasize the importance of developing region-specific osteoporosis prevention strategies.

IGF signaling pathway in bone and cartilage development, homeostasis, and disease

The skeleton plays a fundamental role in the maintenance of organ function and daily activities. The insulin-like growth factor (IGF) family is a group of polypeptide substances with a pronounced role in osteoblast differentiation, bone development, and metabolism. Disturbance of the IGFs and the IGF signaling pathway is inextricably linked with assorted developmental defects, growth irregularities, and jeopardized skeletal structure. Recent findings have illustrated the significance of the action of the IGF signaling pathway via growth factors and receptors and its interactions with dissimilar signaling pathways (Wnt/β-catenin, BMP, TGF-β, and Hh/PTH signaling pathways) in promoting the growth, survival, and differentiation of osteoblasts. IGF signaling also exhibits profound influences on cartilage and bone development and skeletal homeostasis via versatile cell-cell interactions in an autocrine, paracrine, and endocrine manner systemically and locally. Our review summarizes the role and regulatory function as well as a potentially integrated gene network of the IGF signaling pathway with other signaling pathways in bone and cartilage development and skeletal homeostasis, which in turn provides an enlightening insight into visualizing bright molecular targets to be eligible for designing effective drugs to handle bone diseases and maladies, such as osteoporosis, osteoarthritis, and dwarfism.

Association between psychological stress and mandibular condyle structure: an analytical cross-sectional study

OBJECTIVE

The potential influence of psychological factors on temporomandibular joint disorders has been clinically documented. To date, all research examining the impact of psychological stress on the temporomandibular joint has been conducted on animals. This study aims to explore the relationship between psychological stress and the structure of the human mandibular condyle.

METHODS

This cross-sectional study was performed on individuals, who were referred to the radiology division of 5th Azar Hospital for head and neck Computed Tomography (CT) scans. All participants completed a perceived stress questionnaire to determine their level of stress. Bone density and cortical bone thickness were measured as indicators of mandibular condyle structure. Based on multi-slice CT scan data, bone density was calculated in the anterior, middle, and posterior mandibular condyle. The cortical bone thickness was also measured at the anterior and posterior mandibular condyle. Statistical analysis was performed in R 4.0.2 software.

RESULTS

Seventy individuals, aged 18-59 years, participated in this study. The CT scans revealed a decrease in Hounsfield units (HU) and bone mineral density (BMD) in both the anterior and posterior regions. However, in the high-stress group, there was no significant difference in cortical bone thickness in the anterior and posterior regions of the condyle, nor in HU and BMD in the middle region of the condyle. An inverse correlation was observed between BMD and perceived stress in the anterior, middle, and posterior regions of both condyles.

CONCLUSION

The current findings indicate that recent psychological stress is associated with changes in the structure of the condyle.

Age-Related Dysfunction in Balance: A Comprehensive Review of Causes, Consequences, and Interventions

This review delves into the multifaceted aspects of age-related balance changes, highlighting their prevalence, underlying causes, and the impact they have on the elderly population. Central to this discussion is the exploration of various physiological changes that occur with aging, such as alterations in the vestibular, visual, proprioceptive systems, and musculoskeletal degeneration. We examine the role of neurological disorders, cognitive decline, and medication side effects in exacerbating balance issues. The review underscores the significance of early detection and effective intervention strategies in mitigating the risks associated with balance problems, such as falls and reduced mobility. It discusses the effectiveness of diverse intervention strategies, including exercise programs, rehabilitation techniques, and technological advancements like virtual reality, wearable devices, and telemedicine. Additionally, the review stresses the importance of a holistic approach in managing balance disorders, encompassing medication review, addressing comorbidities, and environmental modifications. The paper also presents future research directions, emphasizing the need for a deeper understanding of the complex mechanisms underlying balance changes with aging and the potential of emerging technologies and interdisciplinary approaches in enhancing assessment and intervention methods. This comprehensive review aims to provide valuable insights for healthcare providers, researchers, and policymakers in developing targeted strategies to improve the quality of life and ensure the well-being of the aging population.