Diabetes mellitus (DM) is a metabolic condition marked by disrupted insulin regulation. Mesenchymal stem cellderived exosomes and conditioned medium (CM) have emerged as promising therapeutic candidates for DM. This research explored the medical benefits of exosomes and CM in treating streptozotocin-induced type 1 DM (T1DM) in rats, comparing their efficacy to bone marrow-derived mesenchymal stem cells (BM-MSCs). Fifty albino rats were grouped into five groups (n=10 each): healthy controls, untreated T1DM rats, T1DM rats treated with intravenous BM-MSCs, T1DM rats treated with intravenous exosomes, and T1DM rats treated with intravenous CM. Plasma glucose and insulin concentrations were monitored weekly. Pancreatic β-cell regeneration was analyzed via qRT-PCR, focusing on the expression levels of TGF-β, Smad3, Ngn3, Pdx1, MafA, and insulin genes. Histological evaluation of pancreatic tissue regeneration was performed at weeks 2 and 4 using hematoxylin & eosin and Masson’s trichrome stains. The exosomes- and CM-treated groups demonstrated significantly higher expression of β-cell regeneration markers (TGF-β, Smad3, Ngn3, Pdx1, MafA, and insulin) than the BM-MSCs group. Additionally, these groups demonstrated a marked rise in the area percentage of pancreatic islets and a significant reduction in pancreatic fibrosis, with more pronounced effects at week 4. Exosomes and CM exhibit superior therapeutic efficiency and regenerative potential over BM-MSCs in T1DM, suggesting their promise as cell-free alternatives for diabetes treatment.

Little knowledge is available about the effects of fluoride exposure on the tongue. This study evaluated the effects of sodium fluoride (NaF) on the tongue ultrastructure and detected the ameliorative effects of resveratrol. Forty adult albino rats were separated into 4 groups: the control group was given a balanced diet and purified water. The NaF treated group: received 10 mg/kg/d dissolved in 2.5 ml distilled water once daily for 30 days orally. The NaF+resveratrol group: received NaF 10 mg/ kg/d orally together with resveratrol in a dose of 30 mg/kg daily for 30 days. The resveratrol group was subjected to resveratrol in a dose of 30 mg/kg/d by oral gavage for 30 days. Sections were stained with hematoxylin & eosin, and Masson’s trichrome. Tumor necrosis factor α immunohistochemical study and electron microscopic examinations were done. The oxidative stress markers malondialdehyde, antioxidant reduced glutathione, and the total antioxidant capacity were measured. The NaF group revealed ulceration, necrotic muscle fibers, distorted papillae and a significant increase in malondialdehyde level, and a significant decrease in glutathione and the total antioxidant levels. In the NaF+resveratrol group, pathological changes were less, and the oxidant levels were decreased by the administration of resveratrol with NaF. In conclusion, NaF adversely affects the ultrastructure of the adult rat tongue and resveratrol can ameliorate this effect.