Objective: To study the protective effect of geniposide on photoaging HaCaT cells and explore its possible mechanism. Method: The logarithmic growth phase cells were inoculated at a density of 1×106/mL in 6 hole plate

at a density of 5×104/mL in 96 hole plate.The model of photoaging HaCaT was established by irradiating of 64 mJ·cm-2 (Intensity of 0.61 mW·cm-2 multiply time of 105 s)UVB. The different concentrations of geniposide(5×10-5

5×10-6

5×10-7 mol·L-1) were used for photoaging cell. The superoxide dismutase(SOD) activity

glutathione peroxidase(GSH-Px) activity

malondialdehyde(MDA) content were assayed by kit respectively. The mRNA levels of p38

tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6) were determined by RT-PCR. The secretion levels of TNF-α and IL-6 of cultured HaCaT cells were detected by ELISA. Result: After the UVB irradiation

the activities of SOD and GSH-Px were decreased

the content of MDA

TNF-α and IL-6

the mRNA levels of p38

TNF-α and IL-6 were increased(P<0.01). After treatment with 5×10-5

5×10-6mol·L-1 geniposide

the activities of SOD were risen to(34.72±2.03)

(38.96±3.56) U·mg-1

the activities of GSH-Px were risen to(28.11±2.76)

(40.02±3.63) U·mg-1

the content of MDA were reduced to (4.82±0.42)

(4.60±0.41) nmol·mg-1

the mRNA levels of p38 were reduced to 0.97±0.09

0.94±0.09

the mRNA levels of TNF-α were reduced to 0.57±0.05

0.53±0.05

the mRNA levels of IL-6 were reduced to 0.65±0.06

0.64±0.06

the content of TNF-α were reduced to (34.05±2.43)

(25.55±1.84) ng·L-1

the contents of IL-6 were reduced to (28.51±1.95)

(19.32±1.55) ng·L-1. Compared with the model group

the differences have statistical significance (P<0.05 or P<0.01). Conclusion: The geniposide can inhibit the injury by UVB for HaCaT. And its mechanism may have relationship with the inhibition of oxidative damage

regulatory p38 signal pathway

adjusting the expression of TNF-α and IL-6.