Combating Lead/HFD Neurotoxicity in Rats: The Synergistic Effect of 10-Hydroxydecanoic Acid and Zinc Oxide Nanoparticles
摘要
Exposure to heavy metals and unbalanced diets poses significant global health concerns. This study investigated the neurotoxic effect of chronic lead acetate and high-fat diet (Pb/HFD) co-exposure in rats and the neuroprotective potential of 10-hydroxydecanoic acid (HDA) and zinc oxide nanoparticles (ZnO-NPs). Rats were allocated into naive, HDA, ZnO-NPs, MIX (HDA/ZnO-NPs), Pb/HFD, Pb/HFD + HDA, Pb/HFD + ZnO-NPs, and Pb/HFD + MIX, with 10 rats per group. For 12 weeks, rats received a daily oral dose of PbAc (30 mg/kg) alongside a 40% fat HFD. Following this induction period, groups continued the Pb/HFD exposure for an additional 4 weeks while also receiving a daily dose of either HDA (5 mg/kg), ZnO-NPs (5 mg/kg), or a combination of both. Spatial learning and memory, brain lead content, and key markers of oxidative stress, neuroinflammation, amyloidogenesis, and apoptosis were evaluated. Pb/HFD co-exposure significantly increased brain lead levels, leading to cognitive impairment as evidenced by the Morris water maze test. This was attributed to a rise in oxidative stress, inflammatory responses, and amyloidogenesis, alongside a reduction in antioxidant markers and a proliferation of glial cells. In contrast, HDA effectively mitigated both the cognitive deficits and the underlying neuroinflammation and oxidative stress. Conversely, ZnO-NPs alone were linked to detrimental cognitive effects, primarily through oxidative stress and neuroinflammation. Our findings support a neuroprotective role for HDA and highlight the need for caution regarding ZnO-NPs monotherapy. Critically, the combination of HDA and ZnO-NPs exhibited a synergistic neuroprotective effect, offering a promising and enhanced therapeutic strategy against environmental and dietary neurotoxic stressors.