Protective effect of leptin on induced apoptosis with trichostatin A on buffalo oocytes

Leptin, the 16-kDa product of the obese (ob) gene, primarily secreted from adipose tissue, has been implicated to play an important role in the regulation of food intake and energy expenditure. This study investigated protective effect of leptin on trichostatin A-induced apoptotic on in vitro maturation ratio of buffalo oocytes. Ovaries were collected from abattoir and were transported immediately to the laboratory by a thermos flask containing sterile normal saline with antibiotics. Oocytes were aspirated from 2 to 8 mm visible follicles. Oocytes were placed in a culture plate and then incubated at 38.5 ˚C with 5% CO2 in air for 24 hr. The maturation of oocytes was evaluated under a stereomicroscope. The FITC-Annexin V and propidium iodide staining method was used to detect oocyte apoptosis. In leptin treated groups with 0, 10, 50 and 100 ng mL(-1) and groups that apoptosis was induced, the percentage of oocytes maturation was 77.03, 86.12, 85.08, and 79.89% and 59.96, 56.93 and 51.98, respectively, while the percentage of apoptosis was 8.83, 7.90, 8.58, and 9.39%, and 10.37, 11.57 and 12.03, respectively. Our findings showed that addition of 10 and 50 ng mL(-1) leptin to IVM medium of buffalo oocytes could increase oocyte nuclear maturation, and could decrease oocyte apoptosis when trichostatin A added for inducing apoptosis.