Protective Effect of Quercetin on Morphological and Histometrical Changes of Placenta in Streptozotocin-Induced Diabetic Rat

Background: Maternal diabetes is a metabolic disorder among pregnant mothers that increases the risk of developing growth disorders in the fetus and the placenta. Placental deformity and dysfunction were reported in some studies. These changes have been related to oxidative stress. Quercetin is a component of the flavonoids group that can be found in vegetables, fruits, tea, and herbal supplements and has anti-inflammatory, anti-bacterial, anti-oxidant, and anti-diabetic properties. Objectives: In this experimental study, prophylactic effect of quercetin was evaluated for structural changes of the placenta in diabetic rats. Methods: Twenty-four pregnant Wistar rats were divided equally into four groups, including control, quercetin, diabetic, and quercetin-treated diabetic groups. Diabetes was induced by streptozotocin injection (50 mg/kg/IV), then male rats for mating were put together with female rats. Quercetin was administered (75 mg/kg/gavage), on 0, 7, 14, and 20 days of gestation. On 20th gestation day, the rats from all groups were anesthetized and laparotomized, then the placenta tissue was harvested. In the following, tissue section was stained by H&E and were analyzed histologically. Results: The weight, thickness and diameter of placenta in the diabetic group were increased but there was no significant difference compared to the quercetin treatment. The mean of the labyrinth zone, the number of trophoblastic giant cells and glycogen cells increased in the diabetic group and quercetin significantly reduced these parameters in diabetic rats (P < 0.05). In addition, the mean of junctional zone decreased in the diabetic group, while quercetin increased it (P < 0.05). Conclusions: The results suggest that quercetin has a protective effect on cell proliferation and preservation of placental morphology in pregnant diabetic rats.