Fig. 9. Chloroquine mediated autophagy inhibition potentiates UV-B induced DNA damage whereas pharmacological activator Rapamycin alleviates UV-B induced DNA damage in primary HDFs. Chloroquine (50 µM) pre-treatment upregulates the expression of DNA damage sensor proteins & potentiates the UV-B induced DNA damage in GA pre-treated HDFs as is evident from western blotting analysis of χH₂AX & pP53 proteins (Fig. 9A, 9C & 9D), (*p<0.05, **p<0.01 as compared to UV-B only). Rapamycin pre-treatment (100 nM) significantly downregulated the expression of DNA damage sensor protein pχH₂AX as well of pP53 protein that acts as guardian of cell (Fig. 9B, 9E & 9F), (**p<0.01 as compared to UV-B only) suggesting that modulation of UV-B induced autophagy flux is necessary for HDF survival upon UV-B -irradiation as well as for GA to offer protection to HDFs from UV-B induced insult.