Association of Hydrogen Sulfide with Femoral Bone Mineral Density in Osteoporosis Patients: A Preliminary Study

BACKGROUND: Accumulated evidence has suggested that hydrogen sulfide (H(2)S) has a role in bone formation and bone tissue regeneration. However, it is unknown whether the H(2)S content is associated with bone mineral density (BMD) in patients with osteopenia/osteoporosis. MATERIAL/METHODS: In the present study, we aimed to explore the changes of serum H(2)S in osteopenia and osteoporosis patients. We analyzed femur expression of cystathionine β synthase (CBS), cystathionine γ lyase (CSE), and 3-mercaptopyruvate sulfurtransferase (3-MST), which are key enzymes for generating H(2)S. RESULTS: Sixteen (16%) patients had osteopenia, 9 (9%) had osteoporosis, and 75 (75%) had normal BMD. In comparison with patients with normal BMD (controls), the serum levels of H(2)S were unexpectedly increased in patients with osteopenia and osteoporosis. This increase was much higher in patients with osteoporosis than in those with osteopenia. Serum H(2)S levels were negatively correlated with femoral BMD, but not lumbar BMD. Interestingly, the expression of CBS and CSE were downregulated in femur tissues in patients with osteoporosis, whereas the expression of 3-MST remained unchanged. Serum phosphorus levels, alkaline phosphatase, hemoglobin, and triglycerides were found to be closely associated with CBS and CSE scores in femur tissues. CONCLUSIONS: Serum H(2)S levels and femur CBS and CSE expression may be involved in osteoporosis pathogenesis.