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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Animals, Cell Nucleus, Cell Proliferation, I-kappa B Proteins, Interleukin-2, Ionomycin, Lymphocyte Activation, Mice, Mice, Inbred BALB C, NF-KappaB Inhibitor alpha, NF-kappa B, Phosphorylation, Protein Transport, Signal Transduction, T-Lymphocytes, Tetradecanoylphorbol Acetate, Triterpenes.
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Does ursolic acid inhibit T-cell activation through modulating nuclear factor-κ B signaling? Context: To investigate the effects of ursolic acid (UA) on T-cell proliferation and activation, as well as to examine its effect on nuclear factor-κB (NF-κB) signaling pathway in T cells. T-cells isolated from BALB/c mice were incubated with UA at concentrations ranging from 5-30 μmol/L in the presence of phorbol 12-myristate 13-acetate (PMA) or PMA plus ionomycin. The proliferation of T cells was measured by the MTT assay. The expressions of CD69, CD25, and CD71 on T-cell surface were analyzed using flow cytometry. The level of interleukin-2 (IL-2) in the culture supernatant of activated T cells was quantified by enzyme-linked immunosorbent assay (ELISA). The level of phosphorylated IκB-α (p-IκB-α) in total protein and p65, a subunit of NF-κB, nuclear translocation were measured by Western blot analysis. UA in a dose-dependent manner significantly decreased the proliferation and inhibited the surface expressions of CD69, CD25, and CD71 in murine T lymphocytes upon in vitro activation (P<0.01). Significant reduction of IL-2 production was found in activated T cells treated with UA (P<0.01). The PMA-induced increase in p-IκB-α protein was inhibited, and nuclear translocation of p65 from the cytoplasm was blocked by UA.
assistant
UA is a potent inhibitor for T cell activation and proliferation; these effects are associated with the inhibition of NF-κB signaling pathway. Final Decision: yes