Boeravinone B, a natural rotenoid, inhibits osteoclast differentiation through modulating NF-κB, MAPK and PI3K/Akt signaling pathways

Wnt5a exacerbates pathological bone features and trabecular bone loss in curdlan-injected SKG mice via osteoclast activation

Many studies on osteoblasts have suggested that Wnt5a plays a crucial role in excessive osteoblast activity, which is responsible for ectopic new bone formation, but research on osteoclasts in ankylosing spondylitis (AS) remains relatively limited. This study aimed to explore whether Wnt5a influences osteoclastmediated bone resorption in curdlan-injected SKG mice, a model that mimics AS. Compared to the Vehicle group, the Wnt5a treatment group exhibited statistically higher clinical arthritis scores and increased hindpaw thickness values. Micro- computed tomography (microCT) analysis of hindpaws revealed a significant increase in inflamed and ectopic bone density in the Wnt5a-treated group compared to the Vehicle group. Histological examination also showed pronounced inflammation and structural bone damage in the bone marrow of ankles in the Wnt5a-treated group. Intriguingly, microCT analysis of the femur revealed that trabecular bone loss was markedly observed in the Wnt5a-treated group. Both the number of TRAP-positive osteoclasts and their activity were statistically greater in the Wnt5a-treated group compared to the Vehicle group. Serum markers of bone resorption, but not bone formation, were also significantly elevated in the Wnt5a-treated group. Notably, promotion of osteoclast differentiation by Wnt5a was inhibited following treatment with anti-Wnt5a. These findings suggest that targeting Wnt5a could be a promising strategy for mitigating pathological bone features in AS by modulating osteoclast activity. [BMB Reports 2025; 58(2): 75-81].

Wnt5a exacerbates pathological bone features and trabecular bone loss in curdlan-injected SKG mice via osteoclast activation

Many studies on osteoblasts have suggested that Wnt5a plays a crucial role in excessive osteoblast activity, which is responsible for ectopic new bone formation, but research on osteoclasts in ankylosing spondylitis (AS) remains relatively limited. This study aimed to explore whether Wnt5a influences osteoclastmediated bone resorption in curdlan-injected SKG mice, a model that mimics AS. Compared to the Vehicle group, the Wnt5a treatment group exhibited statistically higher clinical arthritis scores and increased hindpaw thickness values. Micro- computed tomography (microCT) analysis of hindpaws revealed a significant increase in inflamed and ectopic bone density in the Wnt5a-treated group compared to the Vehicle group. Histological examination also showed pronounced inflammation and structural bone damage in the bone marrow of ankles in the Wnt5a-treated group. Intriguingly, microCT analysis of the femur revealed that trabecular bone loss was markedly observed in the Wnt5a-treated group. Both the number of TRAP-positive osteoclasts and their activity were statistically greater in the Wnt5a-treated group compared to the Vehicle group. Serum markers of bone resorption, but not bone formation, were also significantly elevated in the Wnt5a-treated group. Notably, promotion of osteoclast differentiation by Wnt5a was inhibited following treatment with anti-Wnt5a. These findings suggest that targeting Wnt5a could be a promising strategy for mitigating pathological bone features in AS by modulating osteoclast activity. [BMB Reports 2025; 58(2): 75-81].

Dental pulp stem cell-derived intracellular vesicles prevent orthodontic relapse by inhibiting PI3K/Akt/NF-κB-mediated osteoclast activity

BACKGROUND

Orthodontic relapse, the undesired deviation of teeth from their corrected positions, remains a significant challenge in clinical orthodontics. Incomplete periodontal bone remodeling has been identified as a key factor in this process. Despite decades of research, currently there are no effective strategies to prevent relapse.

METHODS

We isolated and identified dental pulp stem cell-derived intracellular vesicles (DPSC-IV) from human dental pulp tissue. To investigate its effect, DPSC-IV was added to osteoblast or osteoclast differentiation medium. During the orthodontic retention period, DPSC-IV was administrated to rats by subgingival injection. Relapse distance and relapse rate were calculated to evaluate DPSC-IV's ability to prevent relapse. Additionally, Western blot analysis were used to examine DPSC-IV's inhibitory effect on osteoclast differentiation.

RESULTS

DPSC-IV significantly promoted osteoblast differentiation and inhibited osteoclast differentiation. Application of DPSC-IV during retention resulted in a significant reduction in both relapse distance and relapse rate, with improved periodontal structure and decreased osteoclast activity. This effect was mediated by the PI3K/Akt/NF-κB signaling pathway and could be reversed by the PI3K activator insulin-like growth factor-1 (IGF-1).

CONCLUSION

This study highlights the potential of DPSC-IV as a novel preventive approach against orthodontic relapse, offering a novel strategy for maintaining long-term orthodontic stability.

Dual intervention of Boeravinone B and Chebulinic Acid mitigates BHT-Induced toxicity in HepG2 cells: modulating apoptosis and autophagy

Butylated Hydroxytoluene (BHT) is found to exert cellular toxicity through induction of oxidative stress although being used as antioxidant in many food products. This study investigates the protective effects of two herbal compounds Boeravinone B (BB) and Chebulinic acid (CA) in combination (B4C3 i.e. BB 4 µg/mL and CA 3 µg/mL). Key findings revealed that BHT exerted toxicity through induction of ROS (234.47 a.u.) and RNS (0.042 µM/mL), but B4C3 has significantly reduced it (115.46 a.u. and 0.018 µM/mL respecctively). BHT exposure raised the activities of antioxidant enzymes such as SOD (70.9%), CAT (7.08 units/mL), GPX (1.21 units/mL), levels of protein carbonyls (3.52 units/mg) and lipid peroxides (418.34%). Whereas treatment with B4C3 decreased the levels of SOD (29.92%), CAT (3.12 units/mL), GPX (0.36 units/mL), protein carbonyls (0.91 units/mg of protein) and lipid peroxides (106.67%) during BHT exposure. It was found that 20.56% cells were apoptotic while 73.83% were autophagic during BHT treatment. However, proposed phytotherapy rescued the cells from apoptotic and autophagic death and supported cell growth which was confirmed by RT-PCR and growth analysis. Collectively, B4C3 offered a significant protection against BHT-induced cellular damage, suggesting its potential as therapeutic agents for oxidative stress-related hepatotoxicity.

Overview of mechanisms and novel therapies on rheumatoid arthritis from a cellular perspective

Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovial inflammation of joints in response to autoimmune disorders. Once triggered, many factors were involved in the development of RA, including both cellular factors like osteoclasts, synovial fibroblasts, T cells, B cells, and soluble factors like interleukin-1 (IL-1), IL-6, IL-17 and tumor necrosis factor-α (TNF-α), etc. The complex interplay of those factors results in such pathological abnormality as synovial hyperplasia, bone injury and multi-joint inflammation. To treat this chronic life-affecting disease, the primary drugs used in easing the patient's symptoms are disease-modifying antirheumatic drugs (DMARDs). However, these traditional drugs could cause serious side effects, such as high blood pressure and stomach ulcers. Interestingly, recent discoveries on the pathogenesis of RA have led to various new kinds of drugs or therapeutic strategies. Therefore, we present a timely review of the latest development in this field, focusing on the cellular aspects of RA pathogenesis and new therapeutic methods in clinical application. Hopefully it can provide translational guide to the pre-clinical research and treatment for the autoimmune joint disease.

p38 mitogen-activated protein kinase contributes to TNFα-induced endothelial tube formation of bone-marrow-derived mesenchymal stem cells by activating the JAK/STAT/TIE2 signaling axis

Bone marrow-derived mesenchymal stem cells (BM-MSCs) can differentiate into endothelial cells in an inflammatory microenvironment. However, the regulatory mechanisms underlying this process are not entirely understood. Here, we found that TIE2 in BM-MSCs was upregulated at the transcriptional level after stimulation with tumor necrosis factor-alpha (TNFα), a major pro-inflammatory cytokine. Additionally, the STAT-binding sequence within the proximal region of TIE2 was necessary for TNFα-induced TIE2 promoter activation. TIE2 and STAT3 knockdown reduced TNFα-induced endothelial tube formation in BMMSCs. Among the major TNFα-activated MAP kinases (ERK1/2, JNK1/2, and p38 MAPK) in BM-MSCs, only inhibition of the p38 kinase abrogated TNFα-induced TIE2 upregulation by inhibiting the JAK-STAT signaling pathway. These findings suggest that p38 MAP contributes to the endothelial differentiation of BM-MSCs by activating the JAK-STAT-TIE2 signaling axis in the inflammatory microenvironment. [BMB Reports 2024; 57(5): 238-243].

Sphingolipid-Induced Bone Regulation and Its Emerging Role in Dysfunction Due to Disease and Infection

The human skeleton is a metabolically active system that is constantly regenerating via the tightly regulated and highly coordinated processes of bone resorption and formation. Emerging evidence reveals fascinating new insights into the role of sphingolipids, including sphingomyelin, sphingosine, ceramide, and sphingosine-1-phosphate, in bone homeostasis. Sphingolipids are a major class of highly bioactive lipids able to activate distinct protein targets including, lipases, phosphatases, and kinases, thereby conferring distinct cellular functions beyond energy metabolism. Lipids are known to contribute to the progression of chronic inflammation, and notably, an increase in bone marrow adiposity parallel to elevated bone loss is observed in most pathological bone conditions, including aging, rheumatoid arthritis, osteoarthritis, and osteomyelitis. Of the numerous classes of lipids that form, sphingolipids are considered among the most deleterious. This review highlights the important primary role of sphingolipids in bone homeostasis and how dysregulation of these bioactive metabolites appears central to many chronic bone-related diseases. Further, their contribution to the invasion, virulence, and colonization of both viral and bacterial host cell infections is also discussed. Many unmet clinical needs remain, and data to date suggest the future use of sphingolipid-targeted therapy to regulate bone dysfunction due to a variety of diseases or infection are highly promising. However, deciphering the biochemical and molecular mechanisms of this diverse and extremely complex sphingolipidome, both in terms of bone health and disease, is considered the next frontier in the field.