[Correlation of DNA methylation status of imprinted gene H19 ICR with oligozoospermia and asthenozoospermia].

OBJECTIVE: To study the correlation of the DNA methylation status of the imprinted gene H19 imprinting control region (ICR) with oligozoospermia and asthenozoospermia. METHODS: We eliminated chromosomal abnormality as the cause of male infertility in the subjects by karyotype analysis and detection of Y-chromosome microdeletions, and identified 18 cases of single factor-induced oligozoospermia (sperm concentration < 15 x 10(6)/ml) and 20 cases of single factor-induced asthenozoospermia (progressively motile sperm <32%) by computer-aided sperm analysis (CASA). Then we extracted genome-wide sperm DNA, treated it with bisul- fite, subjected the target gene fragments to PCR amplification and sequencing. Lastly, we analyzed the DNA methylation status of the target genes with BIQ Analyzer and processed the data using SPSS17.0. RESULTS: The DNA methylation level of the H19 ICR was increased significantly in the oligozoospermia patients ([9.19 +/- 2.45]%, P < 0.05), especially in the severe oligozoospermia males with sperm concentration < 3 x 10(6)/ml (P < 0.01), as compared with that of the 20 fertile control men ([0.30 +/- 0.06]%). However, no significant differences were found in the level ([0.30 +/- 0.07]%) and pattern of the DNA methylation of the H19 ICR (P = 0.62). Further analysis of the DNA methylation status of the CTCF-6 binding sites indicated that the DNA methylation degree was significant higher in the oligozoospermia men ([2.67 +/- 0.75]%) than in the fertile control ([0.05 +/- 0.03]%) or the asthenozoospermia group ([0.03 +/- 0.02]%), with no significant differences between the latter two (P = 0.35). CONCLUSION: The reduced DNA methylation of the H19 ICR is negatively correlated with sperm concentration but not associated with sperm motility.

[Alteration and potential role of soluble fms-like tyrosine kinase receptor 1 in preeclampsia].

OBJECTIVE: To investigate the alteration of serum soluble fms-like tyrosine kinase receptor 1 (sFlt-1) and the possible source in preeclampsia, and the relationship between sFlt-1 and the pathogenesis of preeclampsia. METHODS: (1) Semi-quantitative RT-PCR was carried out to detect the level of sFlt-1 mRNA in placental tissue of 10 preeclampsia (preeclampsia group) and 10 normotensive pregnancies (normotensive pregnancy group). (2) Enzyme linked immunosorbent assay (ELISA) was used to detect the serum level of sFlt-1 in peripheral venous blood in preeclampsia group 1 (n = 35) and normotensive pregnancies group 1 (n = 35); the serum level of sFlt-1 of uterine vein blood in preeclampsia group 2 (n = 20) and normotensive pregnancies group 2 (n = 20); and the volume of peripheral venous blood sFlt-1 in 10 early (early pregnancy group) and 10 middle pregnancies (middle pregnancy group). RESULTS: (1) sFlt-1 mRNA of placental tissue was significantly higher in preeclampsia group (0.95 +/- 0.04) than that in normal pregnancy group (0.64 +/- 0.15). (2) The serum level of sFlt-1 of peripheral vein in preeclampsia group 1 (5640 +/- 3191) ng/L was higher than that in normal pregnancy group 1 (2194 +/- 635) ng/L. (3) The serum sFlt-1 of uterine vein in preeclampsia group 2 (7673 +/- 2296) ng/L was higher than that in normotensive pregnancy group 2 (3057 +/- 785) ng/L, indicating that the volume of sFlt-1 of uterine vein blood was significantly higher than that of peripheral venous blood (P < 0.01). (4) The serum levels of sFlt-1 in early and middle pregnancy groups were (32 +/- 20) ng/L and (994 +/- 302) ng/L, respectively, showing that the level of sFlt-1 in peripheral venous blood increasingly elevated with the development of pregnancy. CONCLUSIONS: (1) The placenta may be the major source of elevated sFlt-1. (2) The serum level of sFlt-1 is related with the development of pregnancy. The alteration of sFlt-1 may contribute to the pathogenesis of preeclampsia.