Effect of Ag Nanoparticles Containing <scp><i>Ocimum basilicum</i></scp> Leaf Extract on Complete Freund Adjuvant‐Induced Arthritis and Methyl Prednisolone Sodium Succinate‐Induced Osteoporosis in Rats

ABSTRACT In the current research, we developed and formulated an innovative therapeutic agent utilizing silver nanoparticles infused with the Ocimum basilicum leaves, aimed at addressing arthritis and osteoporosis. The AgNPs characterization was conducted using techniques such as field emission‐scanning electron microscopy (FE‐SEM), X‐ray diffraction (XRD), ultraviolet–visible spectroscopy (UV–Vis), and transmission electron microscopy (TEM). The distinct peak observed at 448 nm in the UV–Vis spectrum indicated the successful formation of silver nanoparticles. Furthermore, the TEM and FE‐SEM images revealed that these NPs were predominantly spherical (10–50 nm). The potential for anti‐osteoarthritic activity was assessed in vitro through protein denaturation methods involving egg albumin and bovine serum albumin, as well as membrane stabilization techniques, utilizing several concentrations (1–1000 μg/mL). In vivo evaluations were conducted using formaldehyde, CFA, and turpentine oil models at several doses. Additionally, the in vitro antioxidant capacity was evaluated through a reducing power assay. The findings demonstrated concentration‐dependent inhibition of albumin denaturation, along with significant stabilization of RBC membranes, with optimal results achieved at 1000 μg/mL. Similarly, the nanoparticles demonstrated the anti‐osteoarthritic effect with the highest activity noted at 1 mg/kg. The CFA model findings indicated a more pronounced protective efficacy against osteoarthritic lesions and changes in body weight. Furthermore, silver NPs reduced significantly rheumatoid parameters levels, ameliorated the altered hematological factors, and positively influenced both histopathological and radiographic alterations. Additionally, silver nanoparticles showed strong antioxidant qualities. In Wistar rats, osteoporosis was induced by the combination of MPSC (10 mg/kg, subcutaneously, three times a week for 4 weeks) and silver nanoparticles (5 μg/kg/day, oral, for 30 days). This treatment led to an elevation in serum levels of markers associated with bone mineral content, while simultaneously causing a reduction in both urinary and serum levels of bone resorption markers indicative. An increase in the tibia and femur strength was reported, especially at 5 μg/kg of silver NPs. The mechanisms by which silver nanoparticles may counteract glucocorticoid‐induced osteoporosis likely include calcium homeostasis regulation, collagen synthesis, and free radicals neutralization. Collectively, these findings endorse the conventional application of silver nanoparticles as effective agents against osteoarthritis and osteoporosis in humans.