Infection of rats with Taenia taeniformis metacestodes increases hepatic CYP450, induces the activity of CYP1A1, CYP2B1 and COH isoforms and increases the genotoxicity of the procarcinogens benzo[a]pyrene, cyclophosphamide and aflatoxin B1

Abstract

Infection of rat liver by Taenia taeniformis metacestodes produced an increase in total CYP450 content and induced activity of the CYP1A1, CYP2B1 and COH isoforms. Variations in activity and p450 total content were found with increasing time of infection. During increased activity of p450 isoforms, rats were challenged with carcinogens metabolized by the mentioned isozymes and an increased amount of genotoxic damage was found when benzo[a] pyrene, cyclophosphamide and aflatoxin B(1) were used. No change was seen in CYP2E1 activity. These results support previous findings regarding an increased susceptibility to genotoxic damage of infected organisms.

Genotoxicity induced by Taenia solium and its reduction by immunization with calreticulin in a hamster model of taeniosis

“…This finding suggests that the rise in MN‐RET frequency during T. solium infection is produced by the presence of the parasite or its products and not by an increased erythropoiesis rate. Our data are sustained by previous findings of increased MN‐RET frequency in rats infected with Taenia taeniformis [Montero et al, ]. Furthermore, T. solium cysticerci secrete a factor responsible for MN formation in cultured human lymphocytes [Herrera et al, ] and patients with neurocysticercosis display higher frequencies of MN and chromosome alterations than healthy controls [Herrera et al, ].…”

Effect of active infection on cytochrome P450‐mediated metabolism of cyclosporine in renal transplant patients

“…Examples of cytokines are the circulating tumor necrosis factor (TNF)‐α , interferon (IFN)‐γ , interleukin (IL)‐6 and IL‐1 . They are produced in large amounts, are considered first mediators of the host response, and have been proven to inhibit P450 content and activity .…”

Effects of intravenous administration of lipopolysaccharide on cytochrome P450 isoforms and hepatic drug metabolizing enzymes in swine

“…The 20 µg/kg dose of LPS also inhibited hepatic DME activities, which reduced the activity of several CYP-mediated reactions. 21 Although CYP isoforms are recognized as a type of acute-phase protein whose values decrease during an inflammatory response, this conclusion might not be applicable to swine because of the selective decrease of CYP isoforms following LPS exposure. In experiment 1, both reductase activities were inhibited by approximately 70%, whereas in experiment 2, there was a > 2-fold enhancement of cytochrome c reductase activities but cytochrome b 5 reductase activities were unaffected.…”