Inhibitory effect of the pancreatic lipase C-terminal domain on intestinal lipolysis in rats fed a high-fat diet: chronic study.
OBJECTIVE
Previous in vitro experiments, as well as acute assays in rat showed that the C-terminal domain (CT-domain) of porcine pancreatic lipase behaves as a potent specific noncovalent inhibitor of pancreatic lipase. Nevertheless, the potential use of the CT-domain as a therapeutic tool against obesity in humans requires further investigation and would be best achieved using the human CT-domain. In the present study, we investigated the inhibitory effects of the recombinant human CT-domain, in vivo, upon chronic administration to rats fed a high-fat diet.


METHODS
The long-term in vivo study requiring relatively high amounts of the human CT-domain, the domain was overexpressed in Escherichia coli as inclusion bodies and an efficient refolding protocol was designed. The inhibitory effect of the recombinant human CT-domain on the activity of pancreatic lipase from different species was first investigated in vitro. Then chronic assays were performed for 4 weeks in rats fed a high-fat diet with or without a daily dose of 1.2 mg of CT-domain per kilogram rat. The time course of food intake, body weight, plasma parameters, liver lipids, faecal output of fat and total cholesterol were measured.


RESULTS
A high yield of correctly folded recombinant human CT-domain was obtained using our refolding process, as evidenced by the capability of the recombinant domain to inhibit human horse and porcine pancreatic lipases in vitro. The recombinant human CT-domain had no influence on the food intake, but significantly reduced the body weight gain. As compared to control rats, higher amounts of total fat (mainly triglycerides and monoglycerides) and total cholesterol were found in the faeces of the rats treated with the CT-domain. Finally, a decrease in liver triglycerides and nonesterified cholesterol was observed while no significant effect could be detected on the plasma parameters.


CONCLUSIONS
These results demonstrated that the CT-domain efficiently reduces in vivo, lipolysis and subsequently body weight gain in rat fed a high-fat diet. The CT-domain could, therefore, be effective in preventing obesity.
Sebban-Kreuzer
C
C
INSERM-U476 'Nutrition humaine et lipides', Marseille, cedex 5, France.
Ayvazian
L
L
Juhel
C
C
Salles
J-P
JP
Chapus
C
C
Kerfelec
B
B
D000818:Animals; D004041:Dietary Fats / Q000008:administration & dosage*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006801:Humans; D008049:Lipase / Q000037:antagonists & inhibitors* / Q000737:chemistry; D050356:Lipid Metabolism; D008066:Lipolysis / Q000187:drug effects*; D008099:Liver / Q000378:metabolism; D008297:Male; D010179:Pancreas / Q000201:enzymology; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000494:pharmacology; D015430:Weight Gain / Q000187:drug effects
D004041:Dietary Fats; D004791:Enzyme Inhibitors; D011994:Recombinant Proteins; D008049:Lipase