Effect of Different Charged Groups of Cow Follicular Fluid Proteins on In Vitro Oocyte Maturation

Follicular fluid (FF) provides a very important microenvironment for the development of oocyte maturation, ovulation and fertilization. The objective of this study was to determine the effect of different charged groups of cow follicular fluid proteins on in vitro oocyte maturation (IVM) when added to cultured maturation medium. The follicular fluid were obtained from dominant follicle and precipitated by ammonium sulphate (30-50%). The precipitated protein was fractionated into acidic and basic fractions using Macro-Prep High S and Macro-Prep High Q columns, respectively. The fractionated proteins were used as media supplement in IVM medium which replace hormones. The in vitro maturation rates were comparable to those obtained with a positive control medium (TCM 199+ 10% Fetal Bovine Serum+ 10 mg/ml porcine Follicle Stimulating Hormone+ 5 mg/ml Luteinizing Hormone and 1 ng/ml Estradiol). The results showed that the proteins from basic fraction stimulated in vitro maturation rate of oocytes (79.3%) when compare to other groups (78.8%: crude FF and 66.3%: acidic fraction) but did not different with positive control (79.8%). Following cleavage rate, the protein from basic fraction was more efficient (67.1%) than crude FF (65.0%) and acidic fraction (62.5%) but less than control (71.4%). In conclusion, we were able to generate preliminary information on the effect of charged groups of follicular fluid proteins on oocytes maturation. However, the roles of individual proteins from the basic fraction will need more investigation for its future application.