Daphnetin Ameliorates Pathological Damage in NK-92 Cells Induced by High-Glucose and High-free Fatty Acids.

Abstract

Objectives: The present study aimed to characterize the protective role of daphnetin in attenuating HGHF-induced pathological injury in human NK-92 cells.

Methods: The non-toxic concentration of daphnetin was determined using a the Cell Counting Kit-8 (CCK-8) assay. The levels of inflammatory cytokines(TNF-α, IFN-γ, IL-6 and IL-10), in cell supernatants were subsequently detected using the cytometric bead array method. Flow cytometric analysis was then performed to analyze the expression levels of perforin and granzyme B, as well as the cell apoptosis rate.

Results: Daphnetin at a concentration of 10 μg/ml had no significant cytotoxicity on NK-92 cells, and therefore this concentration was selected for subsequent experiments. Compared with the control group, the HGHF group exhibited significantly reduced levels of TNF-α, IFN-γ, IL-6, IL-10, perforin and granzyme B (all P<0.05), along with a significantly increased cell apoptosis rate (P<0.05). Daphnetin treatment led to a marked upregulation of the levels of these inflammatory cytokines and intracellular molecules in both the control and the HGHF groups (all P<0.05); furthermore, the apoptosis rate was appreciably decreased in the HGHF-induced NK-92 cells (P<0.05).

Conclusion: Daphnetin has been shown to alleviate HGHF-induced pathological damage in NK-92 cells both through upregulating the expression of inflammatory cytokines and intracellular molecules (namely, perforin and granzyme B), and via inhibiting cell apoptosis.