Background: Hispidulin, nepetin, and vanillic acid are phenolic compounds potentially possessing immunosuppressive property, however, no information on their pharmacological effect and cytotoxicity has been investigated on human T lymphocytes.Materials and methods: Human peripheral blood mononuclear cells were stimulated with anti-CD3/28 coated beads and treated with individual compound at different concentrations (50-200 µM). Inhibition of early cell activation and induction of apoptosis were analyzed by flow cytometric technique.Results: At 200 µM, frequencies of CD25 and CD69 in CD4+ and CD8+ T lymphocytes were markedly decreased by hispidulin and nepetin. When lowering to 100 and 50 µM, hispidulin had no effect on the expression of CD69 in CD4+ T cells, whereas nepetin selectively suppressed CD25 and CD69 expressions in CD8+ T cells at 100 µM and only inhibited CD69 in CD8+ T cells at 50 µM. For vanillic acid, no inhibitory effect was observed while cell activation was significantly increased for all treated concentrations. None of these compounds disturbed levels of total apoptotic cells in CD4+ and CD8+ populations.Conclusions: Hispidulin and nepetin, therefore, exhibit dose-dependent inhibitory activity of early T-cell activation without inducing cell death, considering feasible immunosuppressants for inflammation-related diseases. However, vanillic acid has no effect on immunosuppression but shows more potential on immunostimulation.HighlightsImmunosuppressive effects of hispidulin and nepetin on human T cells were studied.Dose-dependent activity for T-cell suppression was found in hispidulin and nepetin.Vanillic acid showed immunostimulating potential rather than immunosuppression.All compounds did not induce cell death.

中文翻译：

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通过组蛋白，荆芥蛋白和香草酸确定对人T细胞活化的抑制作用。

背景：组蛋白，荆芥肽和香草酸是可能具有免疫抑制特性的酚类化合物，但尚未对其人T淋巴细胞的药理作用和细胞毒性进行研究。材料与方法：用抗CD3刺激人外周血单个核细胞/ 28包被的珠，并用不同浓度（50-200 µM）的单个化合物处理。结果：在200 µM下，组蛋白和荆芥蛋白显着降低了CD4 +和CD8 + T淋巴细胞中CD25和CD69的频率，其浓度为200 µM。当降低到100和50 µM时，组蛋白对CD4 + T细胞中CD69的表达没有影响，而荆芥蛋白在100 µM时选择性抑制CD8 + T细胞中CD25和CD69的表达，而在50 µM时仅抑制CD8 + T细胞中的CD69。对于香草酸，未观察到抑制作用，而所有处理浓度的细胞活化均显着增加。这些化合物均未扰乱CD4 +和CD8 +群体中总凋亡细胞的水平。然而，香草酸对免疫抑制没有影响，但对免疫刺激却显示出更大的潜力。亮点研究了组蛋白和荆芥肽对人T细胞的免疫抑制作用。