Effects of drugs known to trigger psoriasis on HaCaT keratinocytes / 药学学报

To investigate whether lithium carbonate, propranolol or chloroquine aggravate psoriasis through influencing cytokines of the psoriatic cytokine network, HaCaT keratinocytes were stimulated with TNF-a 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-alpha-stimulated HaCaT cells, production of IL-6 and TNF-alpha 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-a as compared to cells without TNF-alpha-stimulation, the mRNA expression of IL-8 was higher than that of IL-6 with the same concentration of TNF-alpha (P < 0.01). Compared with HaCaT cells cultured with medium alone, propranolol hydrochloride at the concentration of 1 x 10(-6) mol x 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.

Modulatory effect of fumaric acid esters on superoxide-anion generation in human phagocytes / 药学学报

Fumaric acid esters (FAE), mainly dimethylfumarate (DMF), have been shown to be highly efficacious in the treatment of psoriasis. Among the potential side effects of FAE therapy, lymphocytopenia is sometimes observed. In order to address the question whether FAE may interfere with systems of the innate defense, the modulatory role of FAE on the generation of superoxide-anion by human monocytes and neutrophils was studied by measuring the reduction of cytochrome c. Various concentrations of DMF and its metabolite methylhydrogenfumarate (MHF) were used to observe their modulatory effect on superoxide-anion generation by monocytes and neutrophils in response to bacteria (S. aureus and E. coli) and candida (C. albicans). Dexamethasone (DXM, 1 x 10(-7) mol x L(-1)) was also studied at the same time. We found that DXM significantly inhibited superoxide-anion generation from monocytes in response to bacteria and C. albicans, whereas DMF and MHF (10-20 microg x mL(-1)) significantly increased the production of superoxide-anion in monocytes in response to the above mentioned bacteria. DXM, DMF and MHF did not affect superoxide-anion generation of neutrophils. Our data indicate that DMF and MHF enhance superoxide-anion generation in human monocytes as one of the important mechanisms of innate defense against microorganisms.