Why did metabolic syndromes increase among the residents in Bangladesh exposed to arsenic?

<p>Bangladesh has undergone severe arsenic pollution from groundwater due to the installation of more than 8 million tube wells. We have been examining the relationship between arsenic exposure levels and health effects among the residents exposed to arsenic in western areas of Bangladesh. We found that the prevalence of hypertension and hyperglycemia was elevated by arsenic exposure. Serum analysis showed that the levels of oxidized LDL-C increased while those of HDL-C decreased. Although the BMI values were as low as 21-22, their waist circumference and triceps skinfold increased. Judging from these parameters, the prevalence of metabolic syndromes among arsenic-exposed residents increased. We also found that the muscle mass markers, such as serum creatinine concentrations, were decreased by arsenic exposure, and the muscle mass reduction was associated with elevated insulin resistance. Notably, several epidemiological studies conducted in Asian countries, including Japan, have reported that lower serum creatinine levels resulted in subsequent increases in the risk of diabetes. Our preliminary studies on body composition analysis and muscle power measurements showed that arsenic exposure increased fat percent while decreasing muscle power and mass among the residents in Bangladesh. These results suggest that arsenic exposure might have caused sarcopenic obesity. Thus, our findings in Bangladesh may provide new insight into the roles of muscle and lipid metabolism as novel targets of arsenic toxicity.</p>