miR­455 targets FABP4 to protect human endometrial stromal cells from cytotoxicity induced by hydrogen peroxide.

Oxidative stress and dysregulation of antioxidant systems are associated with various complications in pregnancy. Endometriosis is a common gynecologic disease that affects women of reproductive age. Recent studies have indicated that oxidative stress may be involved in the pathophysiology of endometriosis. It has been reported that microRNAs can regulate the cellular response to oxidative stress, and mounting evidence indicates that fatty acid binding protein 4 (FABP4) plays an essential role in the regulation of systemic redox capacity. In the present study, we demonstrated that miR­455 is a putative FABP4­targeting miRNA. A luciferase activity assay revealed that miR­455 can successfully bind to the 3'­UTR of FABP4. Overexpression of miR­455 led to the downregulation of FABP4 at both the mRNA and protein levels in a human endometrial stromal cell line. Then, the roles of miR­455 and FABP4 in oxidative stress induced by hydrogen peroxide (H2O2) in human endometrial stromal cells were examined. We found that ectopic expression of miR­455 protected cells from damage caused by H2O2. Further investigation found that forced expression of miR­455 reduced the level of reactive oxygen species (ROS) and malondialdehyde (MDA), while the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH­Px) were promoted. Silencing of FABP4 also generated cytoprotective effects against H2O2 in human endometrial stromal cells. Moreover, overexpression FABP4 abrogated the miR­455­mediated antioxidative stress effects in cells. Taken together, we propose that miR­455 protects human endometrial stromal cells from oxidative stress at least partly via regulation of FABP4.

[Clinical characteristics of 7 patients with gestational diabetes insipidus].

OBJECTIVE: To investigate the clinical feature, treatment and prognosis of both the mother and the fetus with gestational diabetes insipidus. METHODS: A total of 7 cases of gestational diabetes insipidus collected in the First Affiliated Hospital of Wenzhou Medical College, Wenzhou Combination of Traditional Chinese Medicine with Western Medicine Hospital, and Zhejiang Taizhou Hospital from June 1993 to June 2006 were analyzed retrospectively. RESULTS: Seven cases symptoms all characterized by excessive thirst polydipsia and polyuria. The average 24 h urinary output was between 11 L to 13 L and manifested of hypobaricuria. After effective treatment (three cases were treated with 1-deamino-8-D-arginine vasopressin, another three patients were managed with hydrochlorothiazide, and the last one was cured with antisterone), seven patients with gestational diabetes insipidus did not have any severe consequences. Their symptoms of excessive thirst, polyuria, and polydypsia disappeared from 7 days to 3 months after parturition. Urinary volume returned to normal standard of 1000-2000 ml during 24 hours. Specific gravity of urine recovered normally between a range 1.015-1.025 and serum sodium recovered between 135-147 mmol/L. The average duration of illness was 52 days. Eight newborn infants survived. Two of them were sent to neonatal intensive care unit for treatment. One was because of premature delivery caused by antepartum eclampsia, and the other case was one of the twins who had hydronephrosis. The baby of the first case left hospital after 3 weeks' treatment. The latter one's symptom disappeared 2 weeks after delivery. No obvious symptom was discovered among all the babies through follow-up telephone calls 42 days after childbirth. CONCLUSION: Gestational diabetes insipidus is a rare endocrinopathy complicating pregnancy. This disorder is characterized by excessive thirst, polydypsia, polyuria, hypobaric urine and electrolyte disturbances usually manifesting in the third trimester of pregnancy or puerperium. This is a transient syndrome. The first treatment of choice in patients with gestational diabetes insipidus is 1-deamino-8-D-arginine vasopressin and the second-choice is hydrochlorothiazide. Early diagnosis and appropriate management of the disease may reduce the hazard for both the mother and the fetus during perinatal period.