Effects of high-fat and low-calcium diets on the structure of filiform and fungiform tongue papillae in rats

This study investigated how high-fat and calcium-deficient diets affect the tongue's structure and function in Wistar albino rats. These diets can lead to obesity, oxidative stress, and inflammation, which alter salivary gland function, impair taste bud regeneration, and disrupt epithelial integrity partly through changes in β-catenin signaling. The research examined histological changes in e filiform and fungiform papillae and evaluated β-catenin expression in the tongue epithelium. Forty-five male Wistar rats albino rats were divided into three groups: control, high-fat diet (HFD), and low calcium diet (LCD). The feeding period lasted 12 weeks. Tongue tissues were collected for histological examination using H&E staining, scanning electron microscopy (SEM), and β-catenin immunohistochemistry. Blood samples were analyzed for calcium, insulin, glucose, cholesterol, HDL, LDL, and triglycerides. Both high-fat and calcium-deficient diets led to significant weight gain, increased insulin levels, and disrupted lipid profiles in rats. The high-fat diet caused moderate damage to histological tongue structures and reduced β-catenin expression. In contrast, the calcium-deficient diet resulted in more severe epithelial damage, complete papillary atrophy, and a significant decrease in β-catenin expression (p < 0.001). Both high-fat and calcium-deficient diets adversely affect the filiform and fungiform structure and function, with calcium deficiency showing a more severe and direct impact through disruption of β-catenin signaling and epithelial integrity.