Effects of Alginic Acid on the Porcine Granulosa Cells and Maturation of Porcine Oocytes

ScopeAlginic acid (AA) from brown algae is a marine organic compound. There is extensive use of AA in the food industry and healthcare, suggesting a high probability of AA exposure. The present study investigates the effects of AA on porcine ovarian granulosa cells (GCs) and oocytes to explore its mechanism in female reproduction because of its adverse effects on reproduction.Methods and resultsThe study adds 20 & mu;M AA to the porcine primary ovarian GCs medium and porcine oocyte in vitro maturation (IVM) medium. Estrogen and progesterone levels are downregulated in GCs. Reactive oxygen species are excessive, and the antioxidant capacity declines. Then mitochondria-mediated apoptosis pathway is involved in GCs apoptosis. In addition, scores of autophagosomes are found in the experimental cells. Furthermore, AA significantly inhibits the proliferation of GCs around cumulus-oocyte complexes (COCs) accompanied by abnormal spindle assembly, chromosome arrangement disorder, and aberrant cortical granules distribution in oocytes, leading to a decreased oocyte maturation rate.ConclusionThese findings suggest that 20 & mu;M AA is toxic to sow reproduction by interfering with estrogen production, oxidative stress, mitochondria-mediated apoptosis, autophagy in GCs of sows, and oocyte maturation. AA interferes with cell viability and steroid hormone secretion of porcine ovarian granulosa cells, and induces oxidative stress, apoptosis, and autophagy. In addition, AA prevents granulosa cells diffusion and Polar body I extrusion of porcine oocytes, and causes abnormal spindle morphology, chromosome arrangement and cortical granules distribution, which are toxic to sow reproduction.image

Automated summary

This study investigates the effects of alginic acid (AA) on porcine ovarian granulosa cells (GCs) and oocytes. The results show that AA disrupts estrogen production, induces oxidative stress, apoptosis, and autophagy in GCs. It also impairs oocyte maturation and causes abnormal spindle morphology, chromosome arrangement, and cortical granules distribution. These findings suggest that AA is toxic to sow reproduction.