Effects of drugs known to trigger psoriasis on HaCaT keratinocytes

To investigate whether lithium carbonate, propranolol or chloroquine aggravate psoriasis through influencing cytokines of the psoriatic cytokine network, HaCaT keratinocytes were stimulated with TNF-α after treatment with these drugs. Protein secretion of a set of multiple different cytokines and growth factors in culture supernatants were measured by using a cytokine antibody array technology. Expression of IL-8 and IL-6 mRNA was determined by real-time PCR. In culture supernatants of TNF-α-stimulated HaCaT cells, production of IL-6 and TNF-α could be enhanced by lithium carbonate; production of IL-6 and a panel of cytokines and growth factors could be enhanced by propranolol hydrochloride; and IL-6 was up-regulated by chloroquine diphosphate as well. Real-time PCR analysis showed a significantly dose-dependent increase of IL-8 and IL-6 mRNA expression in HaCaT cells stimulated with TNF-α as compared to cells without TNF-α-stimulation, the mRNA expression of IL-8 was higher than that of IL-6 with the same concentration of TNF-α (P<0.01). Compared with HaCaT cells cultured with medium alone, propranolol hydrochloride at the concentration of 1×10^-6 mol·L^-1 could stimulate HaCaT cells to express higher level of IL-6 mRNA (P<0.05). The drugs investigated show a modulatory effect on certain cytokines and growth factors which are able to modulate inflammatory type of immune reaction present in psoriatic lesions.