Investigating the protective effects of aqueous extract of the wormwood plant (Artemisia absinthium) on alumina nanoparticle-induced pulmonary toxicity in male Wistar rats

Although aluminum oxide nanoparticles (Al2O3-NPs) are the most widely used nanomaterials, limited studies have been reported on their toxicology. Therefore, the present study aimed to investigate the potential toxicity of aluminum oxide (alumina) nanoparticles and the protective role of aqueous extract of wormwood plant on nanomaterial-induced disorders in the lung of rats.

Here, 36 male Wistar rats were randomly divided into six groups. Next, the rats were first exposed to 200 mg/kg of the aqueous extract of wormwood plant (by gavage) for 15 days and then received a dose of 30 mg/kg of aluminum oxide nanoparticles as an intraperitoneal injection for 14 days. Furthermore, various features of clinical signs, body weight, biochemical parameters, gene expression changes, lung weight ratio, histopathological observations, and metal content in lung tissue were evaluated during the experiment. Eventually, the ANOVA (Analysis of Variance) and Tukey’s range test were employed to analyze and compare the mean of the data.

The results revealed that aluminum oxide nanoparticles at a concentration of 30 mg/kg body weight led to changes in antioxidant enzyme activities, e.g., T-SOD, CAT, GPx, and TAC, lipid peroxidation, and iNOS for exposed rats. Also, the above biochemical disorders were associated with altered expression of oxidative stress-related genes (HO-1, MT-1) and histological changes in the lung tissue. On the other hand, simultaneous intake of aqueous extract of wormwood plant and aluminum oxide nanoparticles in rats significantly improved the studied parameters (p <0.05).

Our findings showed that the γ-Al2O3 NPs were more toxic than α-Al2O3 NPs, which can be attributed to changes related to their size and shape characteristics. Also, it was observed that the wormwood plant could play a protective role against aluminum oxide nanoparticles-induced pulmonary toxicity in rats.