D4H-implantation

Ohne Zusammenfassung     

Clinical significance of neuregulin 4 (NRG4) in gestational diabetes mellitus

Objective: Gestational diabetes mellitus (GDM) is defined as glucose intolerance detected during pregnancy. GDM is increasing worldwide and is associated with adverse maternal and fetal outcomes. Neuregulin 4 (NGR4) is epidermal growth factor like signaling molecule. It plays an important role in cell to cell communication furthermore recent studies indicate that NRG4 may work as a novel adipokine with a possible role in maintaining energy and metabolic homeostasis. The aim of the present study was to assess serum NRG4 levels along with several metabolic parameters in patients diagnosed with gestational diabetic mellitus.

Materials and methods: In this prospective cross-sectional study, the study group was composed of 63 women with GDM and 64 healthy pregnant women matched for age, body mass index (BMI) and gestational age. Blood samples were collected at the 24–28th gestational weeks. Serum NRG4, total cholesterol, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), triglycerides, glucose levels during 75-gr OGTT, fasting insulin, glycosylated hemoglobin A1c (HbA1c), alanine aminotransferase (ALT) and creatinine levels were measured. Homeostasis model assessment of insulin resistance (HOMA-IR) values were calculated.

Results: Serum NRG4 values were significantly elevated in the GDM group compared to the control group (p?β?=?0.910, p?β?=?0.866, p?β?=?0.222, p?Conclusions: Serum NRG4 levels were associated with metabolic parameters of GDM. The present study can be considered to be a guide for future studies to clarify the pathophysiology of NGR4 in GDM patients.     

Effects of gossypol on human specific lactate dehydrogenase-C4 (LDH-C4)]

LDH-C4 is a specific isoenzyme, distinct from other LDH isoenzymes with regard to its locality and kinetic properties. Because about 80% of LDH in spermatozoa contains LDH-C4, it must be strongly related to very specific metabolic processes connected with sperm. In order to investigate the mechanism of action of gossypol, which is a new male contraceptive, the effects of gossypol on LDH-C4 were examined. LDH-C4 from human seminal plasma was purified by Oxamate-Sepharose 4B affinity column chromatography and AMP affinity column chromatography. The homogeneity of LDH-C4 was proved by agar gel electrophoresis and polyacrylamide disc gel electrophoresis. Gossypol was dissolved in 95% ethanol. LDH activity was analyzed spectrophotometrically. The cuvette contained 0.1 M PBS (pH 7.4), 0.2 mM pyruvate, and 0.115 mM NADH. Gossypol was added to give a final concentration of between 1 x 10 -6 M and 1 x 10 -4 M. Ethanol did not inhibit LDH-C4 activity, but gossypol did inhibit it in a dose-dependent manner when tested at a concentration of 5 x 10 -6 M, 1 x 10 -5 M, 5 x 10 -5 M, and 1 x 10 -4 M. (author's modified)     

Serum antibodies to LDH-C4

Human sera from the WHO Reference Bank were tested by a liquid phase radioimmunoassay for antibodies to the sperm-specific form of lactate dehydrogenase (LDH-C4; LDH-X). Modestly elevated levels of antibodies were detected in about 10% of infertile males and females and in about 20% of vasectomized males, as well as in a few cases in other categories. The occurrence of this anti-LDH-C4 activity was without overt correlation with other anti-sperm antibody assays. The primary advantage of the radioimmunometric assay is its absolute specificity for a sperm antigen. These findings lend support to contraceptive vaccine development based on LDH-C4 antigenicity.