Role of meiosis activating sterols, MAS, in induced oocyte maturation

A randomized, double-blind, controlled trial of the effect of adding follicular fluid meiosis activating sterol in an ethanol formulation to donated human cumulus-enclosed oocytes before fertilization

OBJECTIVE

To evaluate the effect of follicular fluid meiosis activating sterol (FF-MAS) in a 0.2% ethanol formulation on chromosomal status and development of preembryos.

DESIGN

Multicenter, prospective, randomized, double-blind, five parallel group, controlled trial.

SETTING

Public and private IVF-clinics in Denmark and Sweden.

PATIENT(S)

Two hundred ten women undergoing IVF treatment donated 310 oocytes.

INTERVENTIONS(S)

FSH/hCG primed cumulus-enclosed oocytes randomized to 4 hours exposure of medium with 0.1, 1, or 10 microM FF-MAS dissolved in 0.2% ethanol, medium with ethanol 0.2%, or medium with water for injection (control) before insemination.

MAIN OUTCOME MEASURE(S)

Primary: incidence of human preembryos with chromosomal abnormalities. Secondary: fertilization rate, cleavage rate, and preembryo quality after 68 hours of culture.

RESULT(S)

At the preembryo level, no significant differences in chromosomal abnormality rate were found among any of the groups. At the blastomere level, a significant increased abnormality rate was observed in the ethanol group and the combined FF-MAS groups compared with the control group. No significant differences in fertilization rate, cleavage rate, or preembryo quality were observed among any of the groups and the control group except for a significant reduction in the number of embryos with >or=2 cells at 26 hours in the ethanol group.

CONCLUSION(S)

No negative effect of FF-MAS was observed. However, addition of ethanol 0.2% to standard IVF-medium with or without FF-MAS for culturing cumulus-enclosed oocytes for 4 hours before insemination increased the chromosomal abnormality rate at the blastomere level. Further studies of FF-MAS in a nonethanol formulation are under way.

A review of in vitro gamete maturation and embryo culture and potential impact on future animal biotechnology

This review considers the relationship of in vitro gamete maturation and embryo culture to the future development of animal biotechnology. The areas reviewed are oocyte maturation in vitro and embryo culture and their importance for successful in vitro embryo production. The rapidly developing area of spermatogonial cell transplantation and culture is also reviewed. The scientific milestones leading to the development of each area, the problems and prospects for future development and the possible significance of major advances in each area are discussed.

Conservation and cloning of CYP51: a sterol 14 alpha-demethylase from Mycobacterium smegmatis

The genetic locus encoding cytochrome P450 51 (CYP51; P450(14DM)) in Mycobacterium smegmatis is described here together with confirmation of activity in lanosterol 14 alpha-demethylation. The protein bound azole antifungals with high affinity and the rank order based on affinity matched the ranked order for microbiological sensitivity of the organism, thus supporting a possible role for CYP51 as a target in the antimycobacterial activity of these compounds. Non-saponifiable lipids were extracted from the bacteria grown on minimal medium. Unlike a previous report using growth on complex medium, no cholesterol was detected in two strains of M. smegmatis, but a novel lipid was detected. The genetic locus of CYP51 is discussed in relation to function; it is conserved as part of a putative operon in M. smegmatis, Mycobacterium tuberculosis, Mycobacterium avium, and Mycobacterium bovis and consists of six open-reading frames including two CYPs and a ferredoxin under a putative Tet-R regulated promoter.