Tehran University of Medical Sciences Iranian Journal of Microbiology 2008-3289 18 4 2026 08 04 595 606 Vedam Kanthi Vaishnavi Unit of Oral Pathology, Faculty of Dentistry, AIMST University, Bedong, Kedah Darul Aman, Malaysia; Unit of Microbiology, Faculty of Medicine, AIMST University, Bedong, Kedah Darul Aman, Malaysia Urmila Banik Unit of Pathology, Faculty of Medicine, Nursing & Health Sciences, SEGi University, Kota Damansara, Malaysia Candy Chuah Unit of Microbiology, Faculty of Medicine, AIMST University, Bedong, Kedah Darul Aman, Malaysia Subramani Parasuraman Unit of Pharmacology, Toxicology and Basic Health Sciences, Faculty of Pharmacy, AIMST University, Bedong, Kedah Darul Aman, Malaysia 2026 02 25 2026 05 14 Background and Objectives: Diabetes mellitus (DM) increases the risk of oral candidiasis by impairing immunity and enhancing Candida virulence. Although Lacticaseibacillus rhamnosus GG (LGG) has antifungal potential, its effect in diabetes remains unclear. This study evaluated the efficacy of LGG against C. albicans and C. tropicalis in diabetic rats. Materials and Methods: A fungal suspension (1×10⁷ CFU/mL) was applied to the tongue for three days in the controls and experimental groups of male alloxan-induced diabetic Sprague-Dawley rats. Then, LGG (0.3 mL of 1×10⁸ CFU/mL) was administered for 28 days in the experimental groups. Weekly oral swabs were analyzed, and blood and tongue tissues were evaluated using biochemical, histopathological, and molecular methods (TLR2, TLR4, and Msp1/p75). Results: Diabetic rats showed weight loss and increased oral Candida growth. LGG reduced C. albicans and C. tropicalis counts and stabilized body weight. Haematological and biochemical parameters improved with probiotic treatment. Histopathological examination showed reduced inflammation, and molecular analyses indicated modulation of Msp1/p75 and TLR2/TLR4. Overall, LGG provided antifungal and immunomodulatory benefits in diabetic rats with oral candidiasis. Conclusion: This study assessed the efficacy of LGG against C. albicans and C. tropicalis in diabetic rats. Administration of LGG reduced Candida colonization and maintained normal physiological parameters. These results suggest that LGG has potential as a safe complementary antifungal therapy. https://ijm.tums.ac.ir/index.php/ijm/article/view/6096 https://ijm.tums.ac.ir/index.php/ijm/article/download/6096/1919