Acute effects of polychlorinated biphenyl-containing and -free transformer fluids on rat testicular steroidogenesis.

Abstract

Polychlorinated biphenyl (PCB)-based transformer fluids belong to a class of environmentally persistent mixtures with known toxic effects. Here, we studied the acute effects of Askarel (which contains Aroclor 1260) and two substitute transformer fluids (the silicone oil-based DC561 and the mineral oil-based ENOL C) on rat testicular steroidogenesis. Single intraperitoneal (ip; 10 mg/kg body weight) or bilateral intratesticular (itt; 25 microg/testis) injections of Askarel markedly decreased serum androgen levels 24 hr after administration. In acute testicular cultures from these animals, chorionic gonadotropin-stimulated progesterone and androgen productions were severely attenuated. When itt was injected or added in vitro, Askarel inhibited 3ss-hydroxysteroid dehydrogenase (3ssHSD), stimulated 17[alpha]-hydroxylase/lyase (P450c17), and did not affect 17ss-hydroxysteroid dehydrogenase in testicular postmitochondrial fractions. The ip-injected Askarel did not affect 3ssHSD, but inhibited P450c17, suggesting that a more intensive metabolism of peripherally injected Askarel reduces the circulating levels of active ingredients below the threshold needed for inhibition of 3ssHSD and generates a derivative that inhibits P450c17. In contrast to Askarel, itt-injection (25 microg/testis) of DC561 and ENOL C did not affect in vivo and in vitro steroidogenesis. These findings show the acute effects of Askarel, but not silicone and mineral oils, on testicular steroidogenesis.

Current concepts in neuroendocrine disruption

“…Some PCBs also have been shown to reduce testosterone production, sperm motility and fertilizing capability, as well as alter male accessory structures and inhibit testicular descent in mammals (Andric et al, 2000; Bush et al, 1986; Inglefield and Shafer, 2000). In humans, effects including early menarche, abnormal menstrual cycles, increased incidence of endometriosis, spontaneous abortion, fetal death, premature delivery, and low-weight in offspring have been associated with exposure to PCBs (Cooper et al, 2005; Simmons et al, 2005).…”

Effect of polychlorinated biphenyls (Aroclor-1248) on the secretory function of bovine luteal cells affected by LH, noradrenaline and high density lipoproteins

“…Interestingly, Aroclor enhanced the effect of HDL during the mid-and late-stage of the oestrous cycle. An explanation for this observation is that a single or a number of the PCBs can affect the activity of steroidogenic enzymes (Kannan et al, 1994;Machala et al, 1998;Andric et al, 2000) or to impair lipids metabolism (Bell et al, 1994).…”

Lipoic acid and Calligonum comosumon attenuate aroclor 1260‐induced testicular toxicity in adult rats

“…Gavage volume was adjusted according to the weight of each rat. The doses and duration of treatment were selected as per previous publications (Andric et al, ; Andric et al, ; Selvakumar et al, ; Liu et al, ). The control group of animals was maintained and gavaged corn oil vehicle alone.…”

“…Moreover, Aly et al () reported that Arochlor 1254 impaired spermatogenesis as evidenced, at least partly, by induction of oxidative stress in testicular mitochondria. Andric et al () reported that the Aroclor 1260 based‐transformer fluid Askarel inhibits rat testicular steroidogenesis (3βHSD activity) after in vivo and in vitro applications.…”