Purpose: A multitude of inflammatory cells and chemical mediators initiate a complex cascade that ultimately leads to hepatocyte death and a systemic inflammatory response. This research aimed to investigate the potential effects of sildenafil and neem (Azadirachta indica) extract, in both conventional and nanoparticle (NP) forms, in the treatment of moderate acute liver damage induced by orogastric carbon tetrachloride (CCL₄). Methods: To induce moderate acute hepatic damage a single oral dosage of CCL₄ (2.5 mL/kg body weight) was provided 24 h before euthanasia. In liver damage-induced CCL₄, sildenafil and neem extract were given in conventional and nanoparticle (PLGA or niosome) forms. To find histological anomalies and hepatic changes, behavioral, biochemical, histopathological, and immunohistochemical methods were used. Results: The findings indicated that sildenafil and/or neem extract, especially in NP combination, significantly mitigated CCL₄-induced acute moderate liver damage. Indicators of liver function, including aspartate aminotransferase (AST), alkaline phosphatase (ALP), alanine aminotransferase (ALT), albumin, bilirubin and gamma-glutamyl transferase (GGT), shown improvement, particularly with the nanoparticulation of both therapies. Treatment, particularly in NP forms, improved the levels of malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase activity (GPx) in liver tissues. A significant reduction in NF-κB expression in hepatic tissue was shown in treatment groups. Also, medication resulted in lower levels of interleukin-1 beta (IL-1β), tumor necrosis factor alpha (TNF-α), caspase-3, and transforming growth factor-beta (TGF-β) in the liver tissue homogenates. Liver function was more significantly improved by the drug-NP combination. Conclusions: This study verified the beneficial therapeutic effects of the combination of sildenafil and neem extract, particularly in NP forms, using biochemical, histological, and immunohistochemical analyses in a rat model of liver damage.

Background: Chronic inflammation and immune dysregulation are key drivers of diabetes complications. Rivaroxaban (RX) and sitagliptin (SITA) are established therapies for thromboembolism and glycemic control, respectively. This study evaluated the novel therapeutic potential of nano-rivaroxaban (NRX) alone and in combination with sitagliptin (SITA) in mitigating inflammation and restoring immune balance in streptozotocin (STZ)-induced diabetic rats. Methods: Type 2 diabetes was induced in rats using a single injection of STZ (60 mg/kg). Animals were divided into five groups: control, STZ-diabetic, RX-treated (5 mg/kg), NRX-treated (5 mg/kg), and NRX+SITA-treated (5 mg/kg + 10 mg/kg). After 4 weeks of treatment, blood glucose, coagulation markers, pro-inflammatory cytokines (TNF-α, IL-1β, IL-6), and anti-inflammatory cytokines (IL-35, TGF-β1, IL-10) were analyzed. Histopathological examination of the liver, kidney, pancreas, and spleen was conducted. Immunohistochemistry was used to assess hepatic NF-κB expression. Results: STZ significantly elevated pro-inflammatory cytokines (IL-1β, TNF-α, IL-6) and anti-inflammatory cytokines (IL-35, TGF-β1, IL-10), along with increased hepatic NF-κB expression and histopathological abnormalities in immune organs. NRX significantly reduced inflammatory cytokines, improved histopathological changes in organs, and decreased hepatic NF-κB expression. The combination therapy (NRX + SITA) achieved superior immune modulation, with enhanced cytokine profile restoration, reduced hepatic NF-κB expression, and near-complete histopathological normalization. Conclusions: This study underscores the promise of combining nanoparticle-based drug delivery with established therapies like sitagliptin to achieve superior immune modulation and inflammation control, presenting a potential therapeutic strategy for managing diabetes complications.