Auraptene ameliorates osteoporosis by inhibiting RANKL/NFATc1 pathway-mediated bone resorption based on network pharmacology and experimental evaluation

Sex differences of NF-κB-targeted therapy for mitigating osteoporosis associated with chronic inflammation of bone

Aims

Transcription factor nuclear factor kappa B (NF-κB) plays a major role in the pathogenesis of chronic inflammatory diseases in all organ systems. Despite its importance, NF-κB targeted drug therapy to mitigate chronic inflammation has had limited success in preclinical studies. We hypothesized that sex differences affect the response to NF-κB treatment during chronic inflammation in bone. This study investigated the therapeutic effects of NF-κB decoy oligodeoxynucleotides (ODN) during chronic inflammation in male and female mice.

Methods

We used a murine model of chronic inflammation induced by continuous intramedullary delivery of lipopolysaccharide-contaminated polyethylene particles (cPE) using an osmotic pump. Specimens were evaluated using micro-CT and histomorphometric analyses. Sex-specific osteogenic and osteoclastic differentiation potentials were also investigated in vitro, including alkaline phosphatase, Alizarin Red, tartrate-resistant acid phosphatase staining, and gene expression using reverse transcription polymerase chain reaction (RT-PCR).

Results

Local delivery of NF-κB decoy ODN in vivo increased osteogenesis in males, but not females, in the presence of chronic inflammation induced by cPE. Bone resorption activity was decreased in both sexes. In vitro osteogenic and osteoclastic differentiation assays during inflammatory conditions did not reveal differences among the groups. Receptor activator of nuclear factor kappa Β ligand (Rankl) gene expression by osteoblasts was significantly decreased only in males when treated with ODN.

Conclusion

We demonstrated that NF-κB decoy ODN increased osteogenesis in male mice and decreased bone resorption activity in both sexes in preclinical models of chronic inflammation. NF-κB signalling could be a therapeutic target for chronic inflammatory diseases involving bone, especially in males.

Efficacy of the Chinese herbal medicine Jintiange capsules in the postoperative treatment of osteoporotic vertebral compression fractures: a systematic review and meta-analysis

Background

In traditional Chinese medicine, Jintiange capsules are frequently used to treat metabolic bone diseases and strengthen bones and tendons. The main component of Jintiange capsules is bionic tiger bone powder. However, the active ingredients and proteins are derived from other animal bones, with chemical profiles similar to that of natural tiger bone. This study aimed to explore the efficacy of Jintiange capsules, a Chinese herbal medicine, in the postoperative treatment of osteoporotic vertebral compression fractures (OVCFs).

Methods

In this systematic review, literature was retrieved using PubMed, the Cochrane Library, the Chinese National Knowledge Infrastructure, the Web of Science, the Wanfang Database, the Chinese Biomedical Literature Database, and the Chinese VIP Database from inception to July 2023. The primary outcome measures were the bone mineral density (BMD) and effective rate. The secondary outcome measures were the visual analog pain score (VAS), Oswestry disability index (ODI), Cobb's angle, serum osteocalcin, serum alkaline phosphatase, and adverse events. RevMan 5.4 and STATA 17.0 software were used for data analysis.

Results

We enrolled randomized controlled trials (RCTs) focusing on 1,642 patients in the meta-analysis. The meta-analysis illustrated that Jintiange capsules significantly increased the BMD of the lumbar spine (p < 0.00001), femoral neck (p = 0.0005), and whole body (p = 0.01). The subgroup analysis of Jintiange capsules combination therapy showed that the BMD of the lumbar spine and whole body was significantly improved with Jintiange capsules (p < 0.00001). The test for the overall effect showed that Jintiange capsules had a significantly higher effective rate than the control groups (p = 0.003). Additionally, the overall effect test showed that Jintiange capsules decreased the VAS and ODI (p < 0.00001) and Cobb's angle (p = 0.02), and improved serum OC and ALP (p < 0.00001) compared with the controls. Furthermore, the pooled analysis of adverse reactions showed no serious impacts on the treatment of OVCFs.

Conclusion

Jintiange capsules demonstrate high safety and efficacy in the treatment of OVCFs, including increasing BMD, the lift effect rate, serum OC levels, and pain relief, decreasing the ODI, serum ALP levels, and adverse events, and improving Cobb's angle. Additional research is required to validate the efficacy of Jintiange capsules for the postoperative treatment of OVCFs.Systematic review registration: https://www.crd.york.ac.uk/PROSPERO.

Interleukin-19 promotes bone resorption by suppressing osteoprotegerin expression in BMSCs in a lipopolysaccharide-induced bone loss mouse model

Aims

Osteoporosis is characterized by decreased trabecular bone volume, and microarchitectural deterioration in the medullary cavity. Interleukin-19 (IL-19), a member of the IL-10 family, is an anti-inflammatory cytokine produced primarily by macrophages. The aim of our study was to investigate the effect of IL-19 on osteoporosis.

Methods

Blood and femoral bone marrow suspension IL-19 levels were first measured in the lipopolysaccharide (LPS)-induced bone loss model. Small interfering RNA (siRNA) was applied to knock down IL-19 for further validation. Thereafter, osteoclast production was stimulated with IL-19 in combination with mouse macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor-κB ligand (RANKL). The effect of IL-19 was subsequently evaluated using tartrate-resistant acid phosphatase (TRAP) staining and quantitative real-time polymerase chain reaction (RT-qPCR). The effect of IL-19 on osteoprotegerin (OPG) was then assessed using in vitro recombinant IL-19 treatment of primary osteoblasts and MLO-Y4 osteoblast cell line. Finally, transient transfection experiments and chromatin immunoprecipitation (ChIP) experiments were used to examine the exact mechanism of action.

Results

In the LPS-induced bone loss mouse model, the levels of IL-19 in peripheral blood serum and femoral bone marrow suspension were significantly increased. The in vivo results indicated that global IL-19 deletion had no significant effect on RANKL content in the serum and bone marrow, but could increase the content of OPG in serum and femoral bone marrow, suggesting that IL-19 inhibits OPG expression in bone marrow mesenchymal stem cells (BMSCs) and thus increases bone resorption.

Conclusion

IL-19 promotes bone resorption by suppressing OPG expression in BMSCs in a LPS-induced bone loss mouse model, which highlights the potential benefits and side effects of IL-19 for future clinical applications.

Melatonin induces RAW264.7 cell apoptosis via the BMAL1/ROS/MAPK-p38 pathway to improve postmenopausal osteoporosis

Aims

Currently, the effect of drug treatment for osteoporosis is relatively poor, and the side effects are numerous and serious. Melatonin is a potential drug to improve bone mass in postmenopausal women. Unfortunately, the mechanism by which melatonin improves bone metabolism remains unclear. The aim of this study was to further investigate the potential mechanism of melatonin in the treatment of osteoporosis.

Methods

The effects of melatonin on mitochondrial apoptosis protein, bmal1 gene, and related pathway proteins of RAW264.7 (mouse mononuclear macrophage leukaemia cells) were analyzed by western blot. Cell Counting Kit-8 was used to evaluate the effect of melatonin on cell viability. Flow cytometry was used to evaluate the effect of melatonin on the apoptosis of RAW264.7 cells and mitochondrial membrane potential. A reactive oxygen species (ROS) detection kit was used to evaluate the level of ROS in osteoclast precursors. We used bmal1-small interfering RNAs (siRNAs) to downregulate the Bmal1 gene. We established a postmenopausal mouse model and verified the effect of melatonin on the bone mass of postmenopausal osteoporosis in mice via micro-CT. Bmal1 lentiviral activation particles were used to establish an in vitro model of overexpression of the bmal1 gene.

Results

Melatonin promoted apoptosis of RAW264.7 cells and increased the expression of BMAL1 to inhibit the activation of ROS and phosphorylation of mitogen-activated protein kinase (MAPK)-p38. Silencing the bmal1 gene weakened the above effects of melatonin. After that, we used dehydrocorydaline (DHC) to enhance the activation of MAPK-p38, and the effects of melatonin on reducing ROS levels and promoting apoptosis of RAW264.7 cells were also blocked. Then, we constructed a mouse model of postmenopausal osteoporosis and administered melatonin. The results showed that melatonin improves bone loss in ovariectomized mice. Finally, we established a model of overexpression of the bmal1 gene, and these results suggest that the bmal1 gene can regulate ROS activity and change the level of the MAPK-p38 signalling pathway.

Conclusion

Our study confirmed that melatonin promotes the apoptosis of RAW264.7 cells through BMAL1/ROS/MAPK-p38, and revealed the therapeutic effect and mechanism of melatonin in postmenopausal osteoporosis. This finding enriches BMAL1 as a potential target for the treatment of osteoporosis and the pathogenesis of postmenopausal osteoporosis.

Antioxidant, Anti-Inflammatory, Anti-Menopausal, and Anti-Cancer Effects of Lignans and Their Metabolites

Since chronic inflammation can be seen in severe, long-lasting diseases such as cancer, there is a high demand for effective methods to modulate inflammatory responses. Among many therapeutic candidates, lignans, absorbed from various plant sources, represent a type of phytoestrogen classified into secoisolariciresionol (Seco), pinoresinol (Pino), matairesinol (Mat), medioresinol (Med), sesamin (Ses), syringaresinol (Syr), and lariciresinol (Lari). Lignans consumed by humans can be further modified into END or ENL by the activities of gut microbiota. Lignans are known to exert antioxidant and anti-inflammatory activities, together with activity in estrogen receptor-dependent pathways. Lignans may have therapeutic potential for postmenopausal symptoms, including cardiovascular disease, osteoporosis, and psychological disorders. Moreover, the antitumor efficacy of lignans has been demonstrated in various cancer cell lines, including hormone-dependent breast cancer and prostate cancer, as well as colorectal cancer. Interestingly, the molecular mechanisms of lignans in these diseases involve the inhibition of inflammatory signals, including the nuclear factor (NF)-κB pathway. Therefore, we summarize the recent in vitro and in vivo studies evaluating the biological effects of various lignans, focusing on their values as effective anti-inflammatory agents.