The Effect Upon The Release Of IL-6 In HaCaT Cell Line Under Ultraviolet B Radiation And The Effect Of Antihistamine Reagents Upon It

BackgroundHuman keratinocytes are an important component of skin's immunological system,which can secrete IL-6 and other cytokines. If keratinocytes are exposed to ultraviolet and other external stimulation,quantity of cytokines secretion increases,the cytokines can impact on lymphocytes and other environmental cells,which plays important roles in immune regulatlon,inflammation and tissue proliferation. Excessive irriadiation of ultraviolet,especially ultraviolet B,is one of the most important factors damaging skin,it can induce inflammation,sunburn and the immunologic changes of the skin. Furthermore,excessive long-term irradiation can cause skin aging,even induce skin cancer. IL-6 is an important cytokine,which acts a role in pamogenesis and progress of the inflammatory skin diseases such as psoriasis,atopic dermatitis and acute erythema as result of ultraviolet irradiation. Therefore, studying how ultraviolet B affects secretion of IL-6 by keratinocytes and how the effect is inhibited is useful. ObjectsTo study the effect on the release of IL-6 in HaCaT cell line under ultraviolet B radiation and the effect of H1 receptor antagonist promethazine,H2 receptor antagonist famotidine upon it. Methods1. HaCaT cells were cultured in tissue-cultrue plates at 37@ ,5%CO2 in DMEM media containing 10% fetal bovine serum at a density of about106cells/ml and were exposed to 0,100,3 00,600J/m2 ultraviolet B, supernatants of the cell cultures were collected at 2,4,8,12,24 and 48 h after irriation respectively.2. 10-5 ,10-6 ,10-7 ,10-8 and 0 mol/L promethazine were added into the^cultures after 300 J/m ultraviolet B irradiation, supernatants of the cell cultures were collected at 4,12,24 h after irriation respectively.3. 10-4,10-5,10-6,10-7and 0 mol/L famotidine were added into the cultures after 300 J/m2 ultraviolet B irradiation, supernatants of the cell cultures were collected at 4,12,24 h after irriation respectively.4. IL-6 was detected by ELISA kit for all supernatants,analysis of variance was applied statistically.Results1. Compared with no radiation ,an increase of IL-6 in vitro upon ultraviolet B radiation from HaCaT keratinocytes was observed from 4h for 300 J/m2, from 4h for 600 J/m2, from 24h for 100 J/m2, respectively(P<0.05).2. The production of IL-6 induced by ultraviolet B radiation from HaCaT keratinocytes was inhibited for 10-5,10-6,10-7 and 10-8 mol/L at 12 and 24h after promethazine was added into cultures compared with no promethazine respectively(P<0.05), the inhibitory maximum of IL-6 was 71.15% at 12h for 10-5 mol/L promethazine3. The production IL-6 was inhibited for 10-4 and 10-5 mol/L from 12h and for 10-6 and 10-7 mol/L at 24h after famotidine was added into cultures compared with no famotidine respectively(P<0.05), the inhibitory maximum of IL-6 was 51.85% at 24h for 10-4mol/L famotidine.ConclusionsThese results suggest that ultraviolet B radiation can induce the release of IL-6 in HaCaT cell line,and promethazine and famotidine can inhibit the effect.