RANKL/OPG/TRAIL Plasma Levels and Bone Mass Loss Evaluation in Antiretroviral Naive HIV-1-positive Men

Osteopenia and osteoporosis are common in HIV-1-infected individuals and represent a challenge in clinical and therapeutic management. This report investigated osteopenia/osteoporosis in a group of 31 antiretroviral naive HIV-1-positive men and the role of specific molecules belonging to TNF and the TNF-receptor family in HIV-1-related bone mass loss. Osteoprotegerin (OPG), the receptor activator of NF-kappab-ligand (RANKL), and the TNF-related apoptosis-inducing ligand (TRAIL) were significantly increased in the plasma of antiretroviral naive HIV-1-positive patients compared to a control group of healthy blood donors. In addition, TRAIL and RANKL plasma concentrations were positively correlated to HIV-1-RNA viral load. Measurement of bone mineral density in 20 out of 31 HIV-1-positive subjects disclosed osteopenia/osteoporosis in 40% of these patients. The antiretroviral naive HIV-1-positive subjects with low bone mineral density had a decreased plasma OPG/RANKL ratio and a plasma RANKL concentration >500 pg/ml. Together, these data indicate that plasma concentrations of specific factors involved in bone homeostasis were increased during HIV-1 infection and that RANKL and OPG/RANKL ratio deregulation may be involved in osteopenia/osteoporosis occurring in antiretroviral naive HIV-1 individuals.