Effects of leptin on stress-induced changes of caspases in rat gastric mucosa.
BACKGROUND
In this study, we investigated the effect of leptin on caspase-3, caspase-8, and caspase-9 immunoreactivity and lipid peroxidation in the stomachs of rats exposed to cold-restraint stress.


METHODS
Thirty-two male Wistar Albino rats were used. Rats pretreated with leptin (10 microg/kg per day for 7 days) were restrained in a wire cage for 4 h at 4 degrees C. Spectrophotometric techniques were used for detection of malondialdehyde (MDA) and glutathione (GSH) levels, and immunoreactivity of caspases was investigated by immunohistochemistry.


RESULTS
While the stomach MDA level of the cold-restraint stress group was increased significantly, the level of GSH was decreased when compared with the control group. Caspase-9 and caspase-3 immunoreactivities of the stress group were not changed, while caspase-8 immunoreactivity was decreased. Leptin administration prevented the increase in the MDA level and the decrease in the GSH content of the gastric mucosa in animals subjected to stress. Leptin administration produced no significant change in caspase-8 immunoreactivity but caused a decrease in caspase-3 immunoreactivity.


CONCLUSIONS
Cold-restraint stress decreases the antioxidant capacity of stomach tissue while activating oxidants, and induces apoptosis by an increase in caspase immunoreactivity. The presence of leptin reverses these mechanisms and suppresses the apoptosis.
Vocational School of Health Services, Akdeniz University, Antalya, Turkey.
Sevim
S
Ercan
Ciğdem
C
Ozer
Murat
M
Taş
Deniz
D
Erdoğan
Aydan
A
Babül
D000818:Animals; D017209:Apoptosis; D053148:Caspase 3 / Q000276:immunology*; D053181:Caspase 8 / Q000276:immunology*; D053453:Caspase 9 / Q000276:immunology*; D005753:Gastric Mucosa / Q000276:immunology* / Q000378:metabolism*; D020738:Leptin / Q000502:physiology*; D015227:Lipid Peroxidation; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013312:Stress, Physiological / Q000276:immunology* / Q000378:metabolism*
D020738:Leptin; D053148:Caspase 3; D053181:Caspase 8; D053453:Caspase 9