Abstract

The impact of sublethal toxicity of sodium arsenite on hematological and certain biochemical parameters of the fresh water catfish Clarias batrachus has been analyzed following exposure of sublethal concentration (1 mg/L, 5% of LC50 value) of sodium arsenite for 10, 30, 45, and 60 days. Arsenic bioaccumulation in the blood tissue of the fish increased progressively with increased period of exposure. The values of total erythrocyte count (TECs), total leucocytes count (TLCs), hemoglobin concentration, and packed cell volume (PCV) 1.40 ± 0.03 × 106 /mm3, 174.83 ± 2.74 × 103 /mm3, 5.01 ± 0.26 g/100 ml, 25.00 ± 1.06 were observed respectively at the end of 60 days of exposure. The results of hematological indices were found to be 179.23 ± 8.81fl/cell for mean corpuscular volume (MCV), 35.92 ± 1.89 pg/cell for mean corpuscular hemoglobin (MCH) and 20.17 ± 1.12 g/dl for mean corpuscular hemoglobin concentration (MCHC). The present findings are clearly indicating severe fish anemia due to the arsenic salt exposure. The continued arsenic toxicity results in decreased serum protein concentration that might be a cause for the loss of weight as well as weakness in the fish.

Abstract

Perfluorooctanoic acid (PFOA) is a man-made surfactant with a number of industrial applications. It has a long half-life environmentally and biologically. Past studies suggest a direct relationship between plasma cholesterol and PFOA serum concentrations in humans and an inverse one in rodents fed standard rodent chow, making it difficult to examine mechanisms responsible for the potential PFOA-induced hypercholesterolemia and altered sterol metabolism. To examine dietary modification of PFOA-induced effects, C57BL/6 and BALB/c mice were fed PFOA in a fat- and cholesterol-containing diet. When fed these high fat diets, PFOA ingestion resulted in marked hypercholesterolemia in male and female C57BL/6 mice and less robust hypercholesterolemia in male BALB/c mice. The PFOA-induced hypercholesterolemia appeared to be the result of increased liver masses and altered expression of genes associated with hepatic sterol output, specifically bile acid production. mRNA levels of genes associated with sterol input were reduced only in C57BL/6 females, the mice with the greatest increase in plasma cholesterol levels. Strain-specific PFOA-induced changes in cholesterol concentrations in mammary tissues and ovaries paralleled changes in plasma cholesterol levels. mRNA levels of sterol-related genes were reduced in ovaries of C57BL/6 but not in BALB/c mice and not in mammary tissues. Our data suggest that PFOA ingestion leads to hypercholesterolemia in mice fed fat and cholesterol and effects are dependent upon the genetic background and gender of the mice with C57BL/6 female mice being most responsive to PFOA.