Neurotoxic and neurobehavioral impacts of silica nanoparticles on brain tissue of albino rats with the potential ameliorative efficacy of liposomal curcumin.

Silica nanoparticles (SiO2-NPs) are very desirable candidates for gene and drugs carriers due to their adjustable biocompatibility, but can negatively affect the vital organs like brain. Liposomal Curcumin (LP-Cur) is recognized for its significant anti-inflammatory, anti-apoptotic, and antioxidant properties. Therefore, this study aimed to investigate the potential protective role of LP-Cur against neurotoxicity induced by SiO2-NPs (spherical with average particle size 108.80 ± 9.6 nm) in albino rat brain models. Forty adult male albino rats (average weight (170 ± 20 g)) were categorized into four distinct groups: Group I (control group) received 0.9% saline intraperitoneally, Group II (SiO2-NPs exposed group) was intraperitoneally injected with SiO2-NPs at the concentration of 200 mg/kg body weight daily, Group III (SiO2-NPs + LP-Cur group) was treated with SiO2-NPs (200 mg/kg/day) followed by LP-Cur (80 mg/kg/day) orally, and Group IV (LP-Cur group) was orally administered with 80 mg/kg/day. All therapies were administered over a thirty-day period. Subsequently, the rodents underwent a behavioral, biochemical, histological, and immunohistochemical assessment. This study demonstrated that exposure to SiO2-NPs adversely affect memory and cognitive function. They significantly increased malondialdehyde (MDA) and decreased the reduced glutathione levels. Furthermore, SiO2-NPs significantly decreased the expression of AChE, Nrf-2, and SOD genes, while increasing the expression of caspase-3 and caspase-9 genes. Moreover, SiO2-NPs produced serious histological alterations including increased pericellular spaces vacuolation of the neuropil, vascular dilatation, neuronal degeneration and pyknosis. In addition to an intense caspase-3 and GFAP immunoreaction. However, administering LP-Cur alleviated the neurotoxic effects induced by SiO2-NPs through its potent antioxidant, anti-inflammatory, and anti-apoptotic properties as the liposomal curcumin helps reduce oxidative stress, inhibit lipid peroxidation, and modulate inflammatory signaling pathways such as NF-κB and Nrf2. These effects collectively contribute to protecting cells and tissues from damage induced by SiO2-NPs. Consequently, liposomal curcumin represents a promising therapeutic strategy for preventing or mitigating the progression of oxidative stress-related diseases.