449: Human telomerase reverse transcriptase (hTERT) mRNA expression in hypertensive disorders of pregnancy

HYPERTENSIVE DISORDERS OF PREGNANCY YALI XIONG, DAN LIEBERMANN, ELI J HOLTZMAN, BARBARA HOFFMAN, STACEY JERONIS, SARMINA HASSAN, ENRIQUE HERNANDEZ, OSSIE GEIFMAN-HOLTZMAN, Temple University School of Medicine, Temple University, Obstetrics & Gynecology, Philadelphia, Pennsylvania, Temple University School of Medicine, Temple University, Department of Biochemistry, Fels Institute, Philadelphia, Pennsylvania, Sheba Medical Center, Tel-Aviv University, Israel, Nephrology and Hypertension Unit, Ramat-Gan, Israel OBJECTIVE: To assess hTERT mRNA levels and telomerase activity in different categories of hypertensive disease in pregnancy. STUDY DESIGN: Fresh placental biopsies were collected from 60 patients: the preeclampsia study group, 32 pregnant patients (8 term (T) and 24 preterm (PT) gestation) and non-preeclampsia, control group, 29 pregnant patients (16 T and 13 PT). Total RNA was isolated from placenta tissue and reversely transcribed to c-DNA. The hTERT mRNA relative expression level was detected with a probespecific real-time quantitative PCR assay using -actin as the reference gene. Statistical analysis was performed using the student t test. Parallel experiments to detect the telomerase activity were also employed with the TRAPeze gel-based telomerase detection assay: telomerase from each placental sample was isolated and applied to add telomeric repeats (GGTTAG) onto the 3= end of a substrate oligonucleotide. The extended products were amplified by PCR and the telomerase activity was determined by the size of the extended product with PAGE gel electrophoresis. RESULTS: The ratio of average hTERT mRNA levels in the study group were higher than those in the control group in both preterm (1.71 versus 0.88, p 0.05) and term placentas (1.66 versus 1.15, p 0.05). In the study group, the HELLP cases and the severe preeclampsia cases had the highest average ratios of hTERT mRNA levels: 1.81, 1.80 respectively. The average ratios of eclamptic and preeclamptic mRNA levels were 1.76 and 1.65. In both the preeclamptic (ratio: 1.78 versus 1.54, p 0.05) and control groups (ratio: 1.13 versus 0.93, p 0.05), hTERT mRNA levels were higher in the placentas obtained from patients with Body-mass index (BMI) above 30 compared with patients with lower BMI. The telomerase activity differences were not detected using TRAPeze gel-based telomerase detection assay. CONCLUSION: This work provides novel data on telomerase biology which correlates the elevated hTERT mRNA expression with the progressive clinical manifestations of preeclampsia