[Effects of Abnormal Iron Metabolism on EPO-STAT5 Signaling Pathway in Anemia Patients].

OBJECTIVE: To study the effects of iron metabolism abnormality on EPO-STAT5 signaling pathway in anemia patients. METHODS: According to diseases, the patients were divided into 3 groups: lower risk myelodysplastic syndrome (MDS) group (30 cases) including 14 cases of non-iron over load and 16 cases of iron over load, 12 cases of them were treated by iron chelation therapy; anemia of chronic disease (ACD) group (12 cases) and iron deficiency anemia (IDA) group (12 cases). In addition, the healthy control group was selected. The iron metaloslism index (SF, SI, TIBC), serum level of EPO, plasma level of P-STAT5 and STAT-5 mRNA expression in peripheral blood cells were detected and compared in different groups. Moreover, the effects of iron metabolism abnormality on the expression of EPO and STAT5 in anemia patients were analyzed. RESULTS: compared with non-iron over load group, the EPO level in iron over load group significantly increased (P<0.05), the expression of STAT5 mRNA and P-STAT5 significantly decreased (P<0.05). After iron chelation therapy, the EPO level in serum significantly decreased (P<0.05), the expression of STAT5 mRNA and P-STAT5 was up-regulated significantly (P<0.05). Compared with healthy control group, the expression of EPO in ACD group was down-regulated significantly, while the expression of STAT5 mRNA was not different, but the P-STAT5 expression was down-regulated significantly (P<0.05). Compared with the healtly control group, the EPO expression in IDA group was enhanced significantly (P<0.05), the expression of STAT5 mRNA and P-STAT5 were also significantly enhanced (P<0.05). CONCLUSION: The excessive iron load or chronic inflammation may inhibit the activation of EPO-STAT5 signaling pathway and aggravate the anemia.

Modulating AtDREB1C Expression Improves Drought Tolerance in Salvia miltiorrhiza.

Dehydration responsive element binding proteins are transcription factors of the plant-specific AP2 family, many of which contribute to abiotic stress responses in several plant species. We investigated the possibility of increasing drought tolerance in the traditional Chinese medicinal herb, Salvia miltiorrhiza, through modulating the transcriptional regulation of AtDREB1C in transgenic plants under the control of a constitutive (35S) or drought-inducible (RD29A) promoter. AtDREB1C transgenic S. miltiorrhiza plants showed increased survival under severe drought conditions compared to the non-transgenic wild-type (WT) control. However, transgenic plants with constitutive overexpression of AtDREB1C showed considerable dwarfing relative to WT. Physiological tests suggested that the higher chlorophyll content, photosynthetic capacity, and superoxide dismutase, peroxidase, and catalase activity in the transgenic plants enhanced plant drought stress resistance compared to WT. Transcriptome analysis of S. miltiorrhiza following drought stress identified a number of differentially expressed genes (DEGs) between the AtDREB1C transgenic lines and WT. These DEGs are involved in photosynthesis, plant hormone signal transduction, phenylpropanoid biosynthesis, ribosome, starch and sucrose metabolism, and other metabolic pathways. The modified pathways involved in plant hormone signaling are thought to be one of the main causes of the increased drought tolerance of AtDREB1C transgenic S. miltiorrhiza plants.