Long-term effect of endemic arsenism on oxidative stress and immune function

Abstract

Objective To explore the long-term effect of endemic arsenism on oxidative stress and immune function, and to provide scientific basis for prevention and treatment of the disease in the areas. Methods In 2009, Using cluster sampling and typical investigation, the cross-sectional study was completed. The patient groups and the internal control group were selected in the arsenism areas after 5 years quality improvement of drinking water(Silizhuang village, Daying village and Gucheng village in Shanyin county, Gucheng city, Shanxi province) and they were divided into mild, moderate, severe case and internal control groups, respectively. The external control group was selected in a non-arsenism area(Yangzhuang village in Heshengbu city). The Oxidative stress indicators were determined and analyzed [serum superoxide dismutase (SOD) activity was determined with xanthine oxidase method, glutathione peroxidase(GSH-Px) activity was determined with 2-thio-2-nitrobenzoic acid method, and mmuuity malondisldohyde(MDA) levels was determined with thiobarbituric acid method]. The immune function was determined and analyzed [immunoglobulin G (IgG) was determined with radioimmunoassay method, and serum lysozyme was determined with turbidimetric method]. Results A total of 252 people were surveyed, in which the external control group, the internal control group, mild, moderate and severe patient groups were 56, 57, 49,44 and 46, respectively. Serum SOD activities were (72.19 ± 11.75), (66.96 ± 12.02), (49.79±11.07), (48.54 ±10.56) and (47.68 ± 10.68)kU/L, respectively. The difference of serum SOD activities between the groups was statistically significant(F = 52.42, P ＜ 0.01 ). Serum SOD activities in the external control group were significantly higher than other groups (all P ＜ 0.05). The value in the internal control group was significantly higher than the 3patient groups (all P ＜ 0.05). There were no significant differences between the case groups (P ＞ 0.05). Serum GSH-Px activities of the five groups were (197.41 ± 38.54), (195.02 ± 31.93), (187.26 ± 28.22), (187.24 ± 25.40),(186.88 ± 21.84)U/mg, respectively, and the difference between the groups was not significant(H = 4.21, P ＞0.05). Serum MDA levels of the five groups were (4.51 ± 2.14), (5.88 ± 2.00), (6.44 ± 2.83), (5.89 ± 2.57),(5.88 ± 2.40)μ mol/L, respectively, and the difference between the groups was statistically significant(F = 3.36,P ＜ 0.05). The external control group was significantly lower than other groups(all P ＜ 0.05). No significant difference was observed between other groups(all P ＞ 0.05). Serum IgG levels were(11.16 ± 2.08), (8.15 ± 1.44), (8.77 ±2.54), (9.19 ± 1.97), (8.44 ± 2.52)g/L, respectively, and the difference between the groups was statistically significant(H = 52.92, P ＜ 0.01 ). The external control group was significantly higher than other groups(all P ＜0.05). No significant difference was observed between other groups(all P ＞ 0.05). Serum lysozyme levels were (13.57 ± 5.16), (10.05 ± 3.96), (8.78 ± 3.35), (8.72 ± 3.76), (9.38 ± 4.26)mg/L, respectively, and the difference between the groups was statistically significant (H = 35.00, P ＜ 0.01 ). The external control group was significantly higher than other groups(all P ＜ 0.05). No significant difference was observed between other groups(all P ＞ 0.05). Conclusions The effect of arsenic on the body's oxidative stress response and immune function persists after 5 years of drinking low arsenic water. In addition to intensify arsenic removal from drinking water, it should also strengthen the monitoring of population's health in the diseased areas. Key words: Arsenic poisoning; Oxidative stress; Immunity; Time