Introduction: Hypothyroidism is a serious health problem worldwide, in which the decrease in the level of thyroid hormone results in a variety of subclinical and clinical symptoms. Salivary glands have an important role in oral hygiene and digestion of food. Any changes in their integrity or activity may influence the patient's health. Ashwagandha is medical herb with antioxidant, anti-inflammatory, antifibrotic, antiapoptotic and antiproliferative activities.
Aim of the Work: To evaluate the histological structural changes induced by hypothyroidism on the parotid gland and analyze the possible protective effect of Ashwagandha against these histopathological changes using various histological and immunohistochemical techniques.
Materials and Methods: Forty adult male albino rats were randomly divided into four main groups: group-I acted as a control group, group-II was given 500 mg/kg/day of aqueous extract of Ashwagandha orally for 30 consecutive days, group-III was given carbimazole orally at dose 1.35 mg/kg/day for 30 consecutive days and group-IV was given both carbimazole and aqueous extract of Ashwagandha in the same dose and manner as group II and group III. The parotid gland specimens were processed for different histological and immunohistochemical techniques. Morphometric and statistical studies were also done.
Results: The hypothyroid group's parotid sections revealed irregular acini, acinar cells have cytoplasmic vacuolization acinar cytoplasmic vacuolations, fibrosis, ductal dilatation, vascular congestion, and nuclear changes. There were increased caspase-3, PCNA and alpha-smooth muscle actin (α-SMA) immune-expressions associated with marked increase in the number of mast cells. On the other hand, Ashwagandha co-treatment prevented most of these histological modifications except for small regions.
Conclusion: Hypothyroidism induced several destructive changes in parotid gland. Ashwagandha had a potent ameliorative role against these changes induced by thyroid dysfunction.