Interleukin-18 dose not modulate interleukin-1 toxic effects o n rat islet function / 中国糖尿病杂志

ABSTRACT

Objective　To investigate if there is any effect of interleukin-18 (IL-18) or if IL-18 modulates IL-1β effects on islet fun ction.Methods　Insulin release and nitrite production from isolated islets of newborn Wistar rats were measured after incubation with or w ithout cytokines.Reverse transcription polymerase chain reaction (RT-PCR) was u sed to detect mRNA expression of the IL-18 receptor signaling chain (IL-18Rβ) .Results　(1) There were no significant effects of 0.625～ 10nmol/L of recombinant murine (rm) IL-18 alone on accumulated or glucose-cha llenged insulin release and nitrite production after 24h.(2) 15pg/ml of recombi nant human (rh) IL-1β significantly increased nitrite production and inhibited insulin release.However,0.625～10nmol/L of rm IL-18 failed to modulate the abo ve effects caused by IL-1β.(3) 24h rm IL-12 preincubation failed to sensitize islets to the effects of 10nmol/L of rm or recombinant rat (rr) IL-18 alone or to pri me islets to IL-1β actions on insulin release and nitrite production.(4) IL-1 8Rβ mRNA was not expressed in isolated islets even after exposure to IL-12 for 48h.Conclusion　Unlike IL-1β,IL-18 dose not play a dir ect role in the destruction of islet β-cell function.