Two formulations of the agricultural pesticide adjuvant, Toximul, reduce the glycogen content of HepG2 cells.

Young mice exposed dermally to the Toximul (Tox) class of agricultural pesticide adjuvants have reduced levels of hepatic glycogen, a marker of subclinical toxicity. The present study determined whether these effects on glycogen also occurred in cultured HepG2 cells. Exposure (3 hr) to Tox resulted in significant, concentration-dependent glycogen reductions (up to 70%) relative to control values (76 +/- 3 microg glycogen/mg protein). These reductions did not appear to be due to loss of cell viability, and were reversible with Tox removal. Two different formulations of Tox (3409F and MP-A) differed significantly in the magnitudes of glycogen reduction in the HepG2 cells.

Effects of insulin-like growth factor-type 1 on weight gain and hepatic glycogen during early development in a surfactant/virus mouse model of acute liver failure: correlation with mortality.

Acute liver failure (ALF) was reproduced in young mice exposed daily for 12 days to the industrial surfactant, Toximul 3409F (Tox), and infected on postnatal day (P) 14 with sublethal doses of mouse-adapted human influenza B (Lee) virus (FluB). Combined Tox + FluB treatment potentiated mortality due to non-necrotic ALF. This study tested the hypothesis that mortality would decline if the known losses in energy production due to compromised fatty-acid beta-oxidation were compensated by pharmacological manipulation of hepatic glycogen stores. Glycogen levels, body weights, and mortality were determined without and with injections of insulin-like growth factor-1 (IGF-1). On P25, 13 days after Tox exposure ceased, glycogen levels (mg/100mg) were: 4.0 (control), 1.7 (Tox), 4.3 (FluB), and 2.9 (Tox + FluB). Corresponding cumulative mortalities were 0, 14, 2, and 38%. Following daily IGF-1 injections from P12 to P17, liver glycogen levels on P25 were: 3.5 (IGF-1), 3.9 (IGF-1 + Tox), 12.3 (IGF-1 + FluB), and 5.6 (IGF-1 + Tox + FluB). Unexpectedly, IGF-1 treatment increased mortality to 67% (IGF-1), 89% (IGF-1 + Tox), 63% (IGF-1 + FluB), and 81% (IGF-1 + Tox + FluB). For all groups there was a significant correlation between mortality and poor weight gain. This is the first report of persistent glycogen reductions after surfactant exposure and withdrawal. Their role in potentiating FluB-induced mortality remains to be established.