Apoptosis and differentiation induced by sodium selenite combined with all-trans retinoic acid (ATRA) in NB4 cells / 中华血液学杂志

<p><b>OBJECTIVE</b>To study the effects of low dose sodium selenite combined with all-trans retinoic acid (ATRA) on apoptosis and differentiation of human acute promyelocytic leukemia (APL) NB4 cells.</p><p><b>METHODS</b>Apo-ptosis was detected by translocation of phosphatidylserine (PS) with a Annexin-V kit and DNA fragmentation by agarose gel electrophoresis analysis, cell differentiation was studied by flow cytometry of CD(11b) expression and NBT reduction assay.</p><p><b>RESULTS</b>Five micromol/L sodium selenite or 0.1 micromol/L ATRA alone could not induce apoptosis of NB4 cells within 48 hours. However, combination of the two drugs at the same doses as above could induce significant apoptosis in 48 hours characterized by increased PS translocation and DNA ladder. Sodium selenite at concentration of 2 micromol/L was not able to induce differentiation of NB4 cells, but when combined with 0.1 micromol/L ATRA, CD(11b) expression and NBT reduction were increased as compared with that of 0.1 micromol/L ATRA alone.</p><p><b>CONCLUSION</b>Low dose sodium selenite could enhance the effects of low dose ATRA in inducing apoptosis and differentiation of NB4 cells.</p>

THE ANTIOXIDATIVE ACTION OF MALTOL ON AUTO-OXIDATION OF ERYTHROCYTES / 中国药理学通报

The effect of maltol to prevent erythrocyte from auto-oxidation is presented. When erythrocytes were incubated at 37 ℃ for 24 h in vitro, oxyhemoglobin was decreased, methemoglobin, superoxide freeradical, lipofuscin and Heinz's body were increased as well as membrane proteins were changed. These reactions could be inhibited by maltol.

THF TOXICITY OF MALTOL AND ITS EFFECT ON ANTIOXIDATIVE ENZYME ACTIVITIES OF ERYTHROCYTES IN MICE / 中国药理学通报

According to our previous experimental results, maltol is a powerful antioxidant against autoxidation and oxidative stress of eryth-rocytes. In this report, the toxicity and antioxidative action of maltol in mice was investigated. The results indicated that maltol was not toxic in mice when fed in a dose of 50mg/kg?d-1 (body weight) for 1 month. The antioxidative enzymes ( SOD and Cat ) activities and GSH content of erythrocytes were significantly increased. In addition, the lifespan of houseflies fed with maltol was prolonged.

THE ANTIOXIDANT ACTION OF MALTOL ON ERYTHROCYTE MEMBRANE / 中国药理学通报

Maltol is a chemical derived from Chinese herb Panax Ginseng. The effect of maltol on hemolysis and hydroperoxidation of erythro-cytes induced by active oxygen radical is presented. Maltol could protect hemolysis induced by H2O2 in vitro. When erythrocyte membrane protein was exposed to butylhydroperoxide in vitro, membrane protein was polymerized, and membrane lipids were oxidized to hydroperoxide compound. These oxidative reactions could inhibited by maltol. The results showed that maltol might act as a scavenger of superoxide of hydroxy radical as demonstrated by biochemical method and ESR spin method。