Studies on the cell-immunosuppressive mechanism of Oridonin from Isodon serra

Oridonin promotes CD4+/CD25+ Treg differentiation, modulates Th1/Th2 balance and induces HO-1 in rat splenic lymphocytes

“…CD4 + /CD25 + Tregs suppress activation and proliferation of other (CD25 -) CD4 + and CD8 + T cells through inhibition of IL-2 transcription and promoting cell cycle arrest [30]. In our previous studies on Oridonin, we found that it signifi cantly decreases the proliferation of CD4 + /CD8 + T cells, leads to the cell cycle arrest at the G1 stage and inhibits the expression of IL-2 at the transcription level [22], which is in line with the mentioned function of CD4 + /CD25 + Tregs.…”

“…Recently, we found that Oridonin also has a potent cell-immunosuppressive effect, which is achieved by inhibiting the viability of lymphocytes, blocking DNA synthesis at the G1 stage and inhibiting Th1 cytokines [22]. However, the effects of Oridonin directly on immunosuppressive factors have not yet been studied, so the aim of this study was to test its effect on CD4 + /CD25 + Tregs, Th1/ Th2 balance and HO-1 to explore its mechanism of immunosuppression.…”

“…The cells were assigned to one of four treatment groups: (1) Oridonin-low (Oridonin-L): treated with Oridonin at a fi nal concentration of 12.5 µmol/l (~ EC 50 calculated from the previous cell-viability assay[22]); (2) Oridonin-high (Oridonin-H): treated with Oridonin at a fi nal concentration of 25 µmol/l (~ 2 × EC 50 ); (3) Copp (the positive control): treated with Copp at a fi nal concentration of 50 µmol/l [13]; (4) control: addition of the same volume of DMSO as Oridonin or Copp used above. Cells of all groups were incubated at 37 °C in 5 % CO 2 with no stimulation for 12 h [23] before RT-PCR, Western blotting and enzyme activity assay of HO-1, and incubated with stimulation of ConA (5 µg/ml) for 48 h before other experiments.…”

Injury-induced Platelet-derived Growth Factor Receptor-α Expression Mediated by Interleukin-1β (IL-1β) Release and Cooperative Transactivation by NF-κB and ATF-4

“…BAY 11-7082, like MG132, has been used to define a causal role for NF-B in diseases such as cancer (48), renal failure (49), and the regulation of stress signal transduction pathways (50). Oridonin has only been recently described as an NF-B inhibitor, in the context of immunosuppression (51) and apoptosis in cancer (52). BAY 11-7082, Oridonin, and siRNA thus define a key role for p65 in PDGF-R␣ transcription.…”

B1, a Novel Amonafide Analogue, Overcomes the Resistance Conferred by Bcl-2 in Human Promyelocytic Leukemia HL60 Cells

“…The cytotoxicity assay was carried out by the MTT method (17). Cells were seeded into 96-well culture plates (10 4 Â cells/well) and allowed to attach for 12 hours before treatment.…”