Wogonin Prevents Glucocorticoid-Induced Thymocyte Apoptosis Without Diminishing Its Anti-inflammatory Action

Abstract

Abstract. The effect of wogonin, a flavone highly purified from the roots of Scutellaria baicalensis, on apoptotic cell death was re-evaluated in rat thymocytes. This flavone inhibited glucocorticoid-induced apoptotic changes such as DNA fragmentation, phosphatidylserine translocation, and nuclear condensation in rat thymocytes. Similar inhibition was also observed in apoptosis induced by other inducers such as etoposide. No significant changes of these apoptotic features were observed in rat thymocytes treated with wogonin alone, suggesting that this flavone protects against glucocorticoid-mediated immunosuppression caused by thymocyte apoptosis. Wogonin was reported to possess anti-inflammatory action in some previous studies, but this flavone had no effect on carrageenan-induced paw edema in this study. The simultaneous treatment of wogonin and glucocorticoid neither enhanced nor reduced the anti-inflammatory effect of glucocorticoid. These results indicate that wogonin is likely to prevent the immunosuppression of glucocorticoid without diminishing its drug efficacy as an anti-inflammatory agent.

Wogonin ameliorates lipotoxicity-induced apoptosis of cultured vascular smooth muscle cells via interfering with DAG-PKC pathway

“…Wogonin selectively induces apoptosis in tumor cells but has protective effects on glucocorticoid-induced apoptosis in normal rat thymocytes [46] . This selective antitumor function is largely due to its abilities to reduce inflammation, scavenge oxidative radicals, attenuate NF-ĸB activity, inhibit several genes that are important for regulation of the cell cycle, suppress COX-2 gene expression, block NO, and prevent viral infections [13,[47][48][49] .…”

“…Wogonin has recently been shown to be toxic in malignant cells but has no or little toxicity in normal cells [44][45][46] . Wogonin selectively induces apoptosis in tumor cells but has protective effects on glucocorticoid-induced apoptosis in normal rat thymocytes [46] .…”

Effects of Dexamethasone and Salvia miltiorrhizae on the Small Intestine and Immune Organs of Rats with Severe Acute Pancreatitis

“…Additionally, the pathological scores in the spleen in dexamethason (at 3 h) and Salvia miltiorrhizae (at 3 and 12 h) treated group were markedly lower than that in model control group, and the pathological scores in the spleen in both groups were also lower than that in model control group at various time points, suggesting that both Dexamethasone and Salvia miltiorrhizae can effectively mitigate the pathological changes in the spleen and thymus. Some studies have proved that Dexamethasone is able to reduce the production of inflammatory mediators and inhibit excessive inflammatory response mainly through inducing the apoptosis of immune cells in the thymus [27][28][29][30] and spleen [31][32][33], thereby exerting protective effects on the immune organs. However, the apoptosis of excessive immune cells may weaken the body's immune function.…”

Inhibition of P‐Glycoprotein by Wogonin Is Involved with the Potentiation of Etoposide‐Induced Apoptosis in Cancer Cells

“…[1][2][3] We have found multiple effects of wogonin on apoptosis in previous studies. [4][5][6] The high concentration of the flavone (30-100 μmol/L) diminished apoptosis induced by various inducers, such as dexamethasone and etoposide in thymocytes, one of the normal cells. 4,5 In contrast, the high concentration (100 μmol/L) of wogonin induced apoptosis and the low concentrations (10-30 μmol/L) of this flavone potentiated apoptosis induced by etoposide in HL-60 cells 6 and the Jurkat T-cell line.…”