The impact of sex steroids on osteonecrosis of the jaw

Causal relationship between telomere length and osteonecrosis: Bidirectional two-sample Mendelian randomization analysis

Recent mounting evidence suggests that shortening of telomere length (TL) is associated with impaired bone health; yet, a genetic causal relationship between TL and osteonecrosis remains uncertain. This study aimed to investigate the potential causal relationship between TL and osteonecrosis using bidirectional two-sample Mendelian randomization (MR). Genome-wide association study summary statistics for TL were sourced from the IEU Open genome-wide association study project, while osteonecrosis data were obtained from the FinnGen Biobank database. A range of MR methodologies-including inverse variance weighting, MR-Egger, weighted median, simple mode, and weighted mode-were utilized for analysis, along with the MR-Egger intercept method for horizontal pleiotropy assessment, and Cochran Q and leave-one-out methods for heterogeneity testing. The forward MR analysis indicated a significant causal relationship between TL and osteonecrosis, suggesting that genetically predicted shorter TL is associated with an elevated risk of developing osteonecrosis (OR = 0.611, 95% confidence interval 0.394-0.948, P = .028). The reverse MR analysis revealed no significant influence of osteonecrosis on TL (OR = 0.999, 95% confidence interval 0.994-1.005, P = .802). Analyses for heterogeneity and horizontal pleiotropy yielded robust results. Our study demonstrates that individuals with shorter TL have an increased risk of developing osteonecrosis, whereas osteonecrosis has no effect on TL.

Etiopathogenesis of medication-related osteonecrosis of the jaws: a review

This study compiles the main hypotheses involved in the etiopathogenesis of medication-related osteonecrosis of the jaw (MRONJ). A narrative review of the literature was performed. The etiopathogenesis of MRONJ is multifactorial and not fully understood. The main hypothesis considers the disturbance of bone turnover caused by anti-resorptive drugs. Bisphosphonates and denosumab inhibit osteoclast activity through different action mechanisms, accumulating bone microfracture. Other hypotheses also consider oral infection and inflammation, the antiangiogenic effect and soft tissue toxicity of bisphosphonates, and the inhibition of lymphangiogenesis. Knowledge of the current theories for MRONJ is necessary to define future studies and protocols to minimize the incidence of this severe condition.

C-C Motif Chemokine Ligand 5 (CCL5) Promotes Irradiation-Evoked Osteoclastogenesis

The imbalance that occurs in bone remodeling induced by irradiation (IR) is the disruption of the balance between bone formation and bone resorption. In this study, primary osteocytes (OCYs) of femoral and tibial origin were cultured and irradiated. It was observed that irradiated OCY showed extensive DNA damage, which led to the initiation of a typical phenotype of cellular senescence, including the secretion of senescence-associated secretory phenotype (SASP), especially the C-C motif chemokine ligand 5 (CCL5). In order to explore the regulation of osteoclastogenic potential by IR-induced senescent OCYs exocytosis factor CCL5, the conditioned medium (CM) of OCYs was co-cultured with RAW264.7 precursor cells. It was observed that in the irradiated OCY co-cultured group, the migration potential increased compared with the vehicle culture group, accompanied by an enhancement of typical mature OCs; the expression of the specific function of enzyme tartrate-resistant acid phosphatase (TRAP) increased; and the bone-destructive function was enhanced. However, a neutralizing antibody to CCL5 could reverse the extra-activation of osteoclastogenesis. Accordingly, the overexpression of p-STAT3 in irradiated OCY was accompanied by CCL5. It was concluded that CCL5 is a potential key molecule and the interventions targeting CCL5 could be a potential strategy for inhibiting osteoclastogenesis and restoring bone remodeling.

Recent Advances in the Synthesis, Characterization, and Application of Carbon Nanomaterials for the Removal of Endocrine-Disrupting Chemicals: A Review

The large-scale production and frequent use of endocrine-disrupting chemicals (EDCs) have led to the continuous release and wide distribution of these pollutions in the natural environment. At low levels, EDC exposure may cause metabolic disorders, sexual development, and reproductive disorders in aquatic animals and humans. Adsorption treatment, particularly using nanocomposites, may represent a promising and sustainable method for EDC removal from wastewater. EDCs could be effectively removed from wastewater using various carbon-based nanomaterials, such as carbon nanofiber, carbon nanotubes, graphene, magnetic carbon nanomaterials, carbon membranes, carbon dots, carbon sponges, etc. Important applications of carbon nanocomposites for the removal of different kinds of EDCs and the theory of adsorption are discussed, as well as recent advances in carbon nanocomposite synthesis technology and characterization technology. Furthermore, the factors affecting the use of carbon nanocomposites and comparisons with other adsorbents for EDC removal are reviewed. This review is significant because it helps to promote the development of nanocomposites for the decontamination of wastewater.

Bioinformatic Data Mining for Candidate Drugs Affecting Risk of Bisphosphonate-Related Osteonecrosis of the Jaw (BRONJ) in Cancer Patients

Background. Bisphosphonate-related osteonecrosis of the jaw (BRONJ) leads to significant morbidity. Other coadministered drugs may modulate the risk for BRONJ. The present study aimed to leverage bioinformatic data mining to identify drugs that potentially modulate the risk of BRONJ in cancer. Methods. A GEO gene expression dataset of peripheral blood mononuclear cells related to BRONJ in multiple myeloma patients was downloaded, and differentially expressed genes (DEGs) in patients with BRONJ versus those without BRONJ were identified. A protein-protein interaction network of the DEGs was constructed using experimentally validated interactions in the STRING database. Overrepresented Gene Ontology (GO) molecular function terms and KEGG pathways in the network were analysed. Network topology was determined, and ‘hub genes’ with degree ≥2 in the network were identified. Known drug targets of the hub genes were mined from the ‘drug gene interaction database’ (DGIdb) and labelled as candidate drugs affecting the risk of BRONJ. Results. 751 annotated DEGs ( $\log \text{FC}\ge 1.5$ , $p<0.05$ ) were obtained from the microarray gene expression dataset GSE7116. A PPI network with 633 nodes and 168 edges was constructed. Data mining for drugs interacting with 49 gene nodes was performed. 37 drug interactions were found for 9 of the hub genes including TBP, TAF1, PPP2CA, PRPF31, CASP8, UQCRB, ACTR2, CFLAR, and FAS. Interactions were found for several established and novel anticancer chemotherapeutic, kinase inhibitor, caspase inhibitor, antiangiogenic, and immunomodulatory agents. Aspirin, metformin, atrovastatin, thrombin, androgen and antiandrogen drugs, progesterone, Vitamin D, and Ginsengoside 20(S)-Protopanaxadiol were also documented. Conclusions. A bioinformatic data mining strategy identified several anticancer, immunomodulator, and other candidate drugs that may affect the risk of BRONJ in cancer patients.