Low Concentrations of PCB (Aroclor 1254) Alter Membrane Bound Ion Dependent ATPases in the Hepatocyte Cells of Mice

Abstract

Aroclor 1254, a PCB, notwithstanding its banned status, is still available in the environment in low concentration. Reports on its toxic effects on membrane proteins and the mechanism of actions are rare. Therefore, the present study was conducted to investigate the dose and exposure duration dependent effects of low concentration Aroclor 1254 on total, Na + , K + , Ca ++ and Mg ++ -ATPases on the mouse liver cells. The study tests two hypotheses, (a) the low, environmentally available doses of Aroclor 1254 will cause typical dose and exposure duration dependent responses on the membrane-bound ion dependent ATPases of the hepatic cells and (b) the observed response will be a direct effect of Aroclor on the enzyme protein itself. To check these hypotheses, various groups of mice were exposed to two sublethal doses for three exposure durations of Aroclor 1254. The results indicated no dose dependent effects on the enzymes. However, significant exposure duration dependent changes in membrane bound ATPases were observed. Since the observed changes were mostly enzyme stimulation after subjected to toxication through oral route, the effects of the Aroclor were possibly in the form of indirect oxidative stress through complex chain of reactions exhibited by the cells.

In Vivo Dose and Duration Dependent Effects of a Dioxin (2,3,7,8 TCDD) on Few Lysosomal Enzymes in Mice Brain

“…Dioxin like chlorinated compounds induce oxidative stress by producing intracellular free radicals and ROS [20] . Oxidative stress caused by reactive oxygen species is also speculated to be pathologically important for various neurodegenerative processes and cognitive deficits [26] .…”

“…It was reported that TCDD, in in vivo conditions, generally binds with AhR receptor and targets to blood brain efflux transporter which reduces the accumulation of drug therapeutic agents in neuronal cells [19] . Therefore, the increased intracellular ions are possibly associated with intracellular signaling alteration due to TCDD toxicity [20] . Going through the literature it was observed that studies related to TCDD effects on lysosomal enzyme in brain tissue are rare.…”

Fish pollutants MeHg and Aroclor cause permanent structural damage in male gonads and kidneys after prepubertal exposure

“…Pathak and Kundu (2013) demonstrated that the renal toxicity attributed to Aroclor is not dose dependent, but the length of exposure is crucial for the production of such adverse effects. Treatments with MeHg and Aroclor in mixture did not cause tubular degeneration, but induced mononuclear infiltration, with the predominance of lymphocytes and glomerular hypercellularity.…”

“…In one of these animals, it was observed hyaline casts. Pathak and Kundu (2013) demonstrated that the renal toxicity attributed to Aroclor is not dose dependent, but the length of exposure is crucial for the production of such adverse effects.…”

Dose and duration dependent toxicity of Dioxin (2,3,7,8 TCDD) to few lysosomal enzymes in mice kidney

“…These organochlorine pollutants are lipophilic and tend to accumulates in adipose tissue so symptoms relevant to toxicity manifest after starvation condition of living organism [32][33][34] . The alterations in the enzyme activities possibly showed cell defense toward incoming ROS which might have formed outside renal cells [35] . *Significance at P = 0.05 (F crit = 5.14)…”