Effects of zinc deficiency and arsenic exposure on bone in growing female mice

Abstract

Abstract Arsenic contamination in groundwater often co-exists in regions prone to zinc deficiency. The goal of this research was to evaluate the independent and combined effects of zinc status [adequate, marginally-deficient, severely-deficient (30, 6, and < 0.5 mg Zn/kg diet)] and arsenic exposure (0, 50, or 500 ppb sodium arsenite) on bone in growing female mice (n = 7–8/treatment). Two experiments were conducted; the first focused on 4 weeks of severe zinc deficiency, the second on 6 weeks of marginal zinc deficiency. Bone response was evaluated in femurs using dual energy X-ray absorptiometry and microcomputed tomography. Severe zinc deficiency resulted in lower total femur bone mass, lower midshaft cortical thickness, and lower cancellous bone volume fraction in distal femur. Arsenite exposure did not significantly alter bone response to consuming a zinc-deficient diet. Neither marginal zinc deficiency nor combined marginal zinc deficiency and arsenite exposure affected the endpoints evaluated. In summary, severe but not marginal zinc deficiency, in growing mice, lowered bone mass and altered bone microarchitecture. In contrast, exposure to arsenite had little effect on bone in severely zinc-deficient, marginally zinc-deficient, or zinc-adequate mice.