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We have examined the effects of nitric oxide donors and acrylamide on mesenchymal progenitor cell (hMPC) viability, programmed cell death (PCD) and differentiation. Acrylamide was examined at 0.5mM and 1.5mM concentrations, NOC-18 at 10μM and SNP at 100μM. Cell viability was assayed with MTS, PCD was determined by phosphatidylserine, caspase-9 and -3/7 and mitochondrial membrane potential assays, and osteogenic cell differentiation was evaluated by alkaline phosphatase activity (ALP) and mRNA levels for collagen type I, bone sialoprotein, ostepontin and osteocalcin. Serum-free hMPC cultures treated with 1.5mM acrylamide and SNP for 72h demonstrated reduced viability. PCD analyses revealed that SNP stimulated cells to necrosis in reactive species-dependent manner. Acrylamide (1.5mM) led to apoptosis independent of reactive species. Acrylamide and SNP reduced ALP activity and collagen type I mRNA levels but mRNA levels for bone sialoprotein and osteopontin increased in SNP treated cells and remained unchanged in acrylamide. Acrylamide had no effect on guanylate cyclase and cGMP osteogenic signaling pathway. The study suggests that acrylamide might impair bone development and remodeling upon acute or prolonged intoxication with this compound of mesenchymal cells., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Salts of divalent cadmium are well-known human mutagens and carcinogens. In the present work, the ability of vitamin C to modulate genotoxic effects of cadmium chloride on human lymphocytes was assessed using single cell gel electrophoresis (comet assay). Vitamin C at 20 and 100 micromol/l and cadmium at 5, 30 and 150 micromol/l significantly increased the tail moment of lymphocytes. Vitamin C also increased the tail moment of cells exposed to cadmium. This effect was concentration-dependent: the higher the vitamin C concentration the greater the tail moment. The combined effects of cadmium and vitamin C were more pronounced at all concentrations tested than the sum of the effects of the compounds applied separately (p < 0.05), so cadmium and vitamin C can be considered to have synergistic effects. The results obtained can be partly explained by the participation of cadmium in the Fenton reaction and reduction of its oxidized form by vitamin C.