Objective: Diabetes mellitus (DBT), chronic alcohol (ALC) consumption, and combination antiretroviral therapy (cART) impair bone turnover by reducing osteoblastogenesis, increasing osteolysis, and heightening fracture risk. The combined detrimental effects of the metabolic and pharmacological challenges on bone cells and osteogenic cytokine profiles remain poorly understood.

Aim: To evaluate the influence of DBT, ALC, and cART on bone cell populations and immunolabeling of pro‑and anti-osteogenic cytokines in the mandibular bone of male diabetic Sprague-Dawley rats.

Methods: Fifty-eight adult male, 10 weeks old  rats were divided into ten groups: control, ALC, DBT, cART, ALC+cART,  DBT+ALC, DBT+cART, DBT+ALC+cART, GEL, and buffered citrate (CB). ALC was administered as 10% v/v ethanol, and cART was given at an extrapolated adult dose of 0.023 mg/kg daily for 12 weeks. Diabetes was induced with a 20% fructose diet and a single streptozotocin injection (40 mg/kg). Diabetes was confirmed by fasting blood glucose level (>250 mg/dL) and serum insulin. Mandibular bones were harvested after 12 weeks, fixed, decalcified, and processed for histological (H&E) and immunohistochemical (TRAP, BMP‑3, and TGF‑β1) analysis.

Results: ALC, cART, DBT, or their combinations increased bone marrow adiposity. BMP‑3 inhibition was associated with reduced osteocyte numbers (TRAP-positive cells) without a significant change in the expression of TGF-β1.

Conclusion: Diabetic conditions compounded by alcohol and cART exposure exacerbate bone deterioration through increased adipogenesis, reduced osteoblastogenesis, and enhanced osteolysis. Continuous monitoring of bone health is warranted in patients with these risk