The effect of olestra on the absorption, excretion and storage of 2,2′,5,5′ tetrachlorobiphenyl; 3,3′,4,4′ tetrachlorobiphenyl; and perfluorooctanoic acid

Abstract

Mice were gavaged with either 14C-labeled 2,2’5,5’ tetrachlorobiphenyl; 3,3’,4,4’ tetrachlorobiphenyl; or perfluorooctanoic acid. Absorption of these compounds was determined by assay of feces collected for 48 hours after the gavage. Part of the animals received test diets containing olestra during this 48-hour period to determine its effect on absorption of the compounds. Mice that received the diet without olestra during this period were divided into groups that either continued the diet without olestra or changed to a diet containing olestra. These diets were continued for 7 days, and a second 48-hour fecal collection was made to measure the effect of olestra on enterohepatic circulation of the compounds and their metabolites. The animals were sacrificed, and blood, fat, and liver concentrations of 14C were measured. Olestra decreased the absorption of 2,2’,5,5’ tetrachlorobiphenyl. It also reduced tissue and blood concentrations of this compound. Olestra also decreased the absorption of 3,3’,4,4’ tetrachlorobiphenyl, but it did not alter enterohepatic circulation or tissue concentrations. Olestra significantly increased the excretion of perfluorooctanoic acid in the second 48-hour collection, suggesting an effect on enterohepatic circulation. It did not, however, alter tissue concentrations of perfluorooctanoic acid. These data are consistent with previously observed effects of olestra on the absorption and storage of lipophilic compounds.

Polychlorinated biphenyls and links to cardiovascular disease

“…Recent research has shown that nutritional intervention that promotes a diet rich in antioxidants as well as a healthy lifestyle can help modulate the toxic effects of many of the environmental pollutants present in the human body, including PCBs (Baker et al 2013, Han et al 2012, Newsome et al 2014, Petriello et al 2014a, Petriello et al 2014b). Also, certain dietary fats may decrease overall body burdens by increasing excretion rates (Jandacek et al 2014, Jandacek et al 2010). Finally, novel evidence now implicates exercise as a mediator of pro-inflammatory pollutants such as PCBs and deserves increased investigation as a modulator of environmental pollutant-induced disease (Murphy et al 2015).…”

Exercise protects against PCB-induced inflammation and associated cardiovascular risk factors

“…Nutritional intervention, such as with olestra, can interfere with the absorption of dietary PCBs and has been shown to result in their reduced systemic accumulation (Jandacek, Rider, Keller, & Tso, 2010). Similar to such nutritional intervention that suggests modification of enterohepatic circulation or reduced re-absorption of organochlorine compounds (Jandacek &Genuis 2013), PCBs and their metabolites may undergo enhanced enterohepatic circulation during exercise.…”

N-acetylcysteine (NAC) diminishes the severity of PCB 126-induced fatty liver in male rodents

“…Several attempts have been undertaken to ameliorate the adverse effects of halogenated biphenyls with dietary interventions, for example with fat substitutes like olestra (Jandacek et al , 2010), minerals like selenium (Stemm et al , 2008; Lai et al , 2011) and manganese (Wang, submitted), various antioxidants (Robertson et al , 1983; Tharappel et al , 2008), or phytochemicals (Glauert et al , 2008). Generally these dietary manipulations resulted in only marginal success.…”