Effect ofeschericia coliendotoxin on tissue lipoprotein lipase activities in chickens

Abstract

1. Four-week-old broiler chickens were injected intravenously with from 0.01 to 1 mg of E. coli endotoxin/kg body weight or with saline. 2. At all doses used endotoxin markedly depressed food intake and lipoprotein lipase activities in muscle and adipose tissue within 8 h. Heart lipoprotein lipase activity was significantly depressed only at doses of 0.1 mg endotoxin/kg body weight or greater. 3. Treatment of birds with 0.3 mg endotoxin/kg body weight reduced post-heparin lipoprotein lipase activity to 0.13 of that in control birds in 8 h. 4. Endotoxin generally depressed plasma very-low-density lipoprotein concentration. Plasma non-esterified fatty acid concentration was significantly elevated only in birds given 1 mg endotoxin/kg body weight. 5. Fatty acid synthetase activity in the liver of endotoxin-treated birds was significantly lower than in control birds 16 h after administration of endoxin, but not after 8 h. 6. These results show that tissue lipoprotein lipase activity in birds is very responsive to E. coli endotoxin, as in mammals. Hypertriglyceridaemia occurs only occasionally in endotoxin-treated chickens, most probably because of the particularly close relationship between food intake and hepatic lipoprotein synthesis in birds.

Monokines in Growth and Development

“…Several hours later acetyl-CoA carboxylase and fatty acid synthetase are increased and the allosteric inhibitor fatty acyl-CoA is reduced (Feingold et al, 1989). Although there is little known about the effect of monokines on avian lipogenesis in vivo, the injection of endotoxin in chickens did not change hepatic fatty acid synthetase activity in contrast to fasted controls (Griffin and Butterwith, 1988). Incubation of chick hepatocytes with conditioned medium from LPS-stimulated HD-11 macrophage cells or human TNF does not significantly alter lipogenesis.…”

“…Tissue LPL activities in birds are reported to be less responsive to the nutritional state than in mammals (Husbands, 1972). However, chicken adipose, leg muscle, and heart LPL levels are significantly reduced by endotoxin injections in comparison with fasted controls (Griffin and Butterwith, 1988). Crude chicken monokine preparations, as well as preparations enriched for chicken IL-1, inhibit LPL activity in murine 3T3-L1 adipocytes (Klasing and Peng, 1990).…”

“…Plasma levels of very low density lipoproteins (VLDL) are generally reduced in comparison to fed controls (Griffin and Butterwith, 1988). This effect is in contrast to mammals, in which hyperlipidemia due to the accumulation of VLDL occurs rapidly after an injection of endotoxin and persists for several hours.…”

Plasma lipoprotein metabolism and fattening in poultry

“…Total activity in adipose tissue and skeletal muscle is either unaffected or slightly reduced by fasting, whereas that in cardiac muscle increases only slightly (Evans, 1972;Husbands, 1972;Benson and Bensadoun, 1977;Griffin and Butterwith, 1988). Total activity in adipose tissue and skeletal muscle is either unaffected or slightly reduced by fasting, whereas that in cardiac muscle increases only slightly (Evans, 1972;Husbands, 1972;Benson and Bensadoun, 1977;Griffin and Butterwith, 1988).…”

Avian adipose tissue: growth and metabolism

“…We have recently demonstrated that endotoxin administration can have a dramatic effect on lipoprotein lipase activity in broilers (Griffin and Butterwith, 1988). We have recently demonstrated that endotoxin administration can have a dramatic effect on lipoprotein lipase activity in broilers (Griffin and Butterwith, 1988).…”