Toxic effects of zinc oxide nanoparticles and histopathological and caspase-9 expression changes in the liver and lung tissues of male mice model

Characterization, dose dependent assessment of hepatorenal oxidative stress, hematological parameters and histopathological divulging of the hepatic damages induced by Zinc oxide nanoparticles (ZnO-NPs) in adult male Sprague Dawley rats

Nanoparticles are beneficial in many aspects to human life but their excessive use can cause various abnormalities. They dispose in the environment through transport, industrial and agricultural usage and enter in living body through dermal, respiratory route or ingested with the lipsticks and there higher concentration produces toxicity. Therefore, current study characterized ZnO-NPs to evaluate toxic ability by X-rays diffraction (XRD) and Scanning Electron Microscopy (SEM) techniques and showed 29.83 and 35 nm size, respectively with hexagonal crystalline structure. LC50 value of ZnO-NPs was also evaluated as 72.48 ± 10.33 mg/kg BW. Male Sprague Dawley (Post weaning) rats were divided into five groups with five rats in each group. Control (C) group received no treatment, placebo (S) group received normal saline (0.9% sodium chloride) intraperitoneally and three treated groups received different levels of ZnO- NPs intraperitoneally at the dose of either 10 or 20 or 30 mg/kg for 21 days on alternate days and named as 1G1, 1G2 and 1G3, respectively for the assessment of toxicity for better understanding of precautionary measures in future. Oxidative stress enzymes of liver and kidney, hepatorenal function enzymes and hematological parameters along with hepatic histology were measured at the end of the experiment. Results showed highly significant variations in all parameters in a dose dependent manner as compared to control group while groups receiving 10 or 20 mg/kg of ZnO-NPs showed low to moderate pathological changes in both organs. Liver histological analysis showed congestion, necrosis, hemorrhage, RBC's accumulations; inflammatory cells infiltration and severe abnormalities in high dose group while medium, low dose group showed moderate and least effects, respectively. It is concluded that ZnO-NPs are highly toxic at more concentration so their careful usage is needed in daily routine.

Meta-analysis of in-vitro cytotoxicity evaluation studies of zinc oxide nanoparticles: Paving way for safer innovations

Nano-based products have shown their daunting presence in several sectors. Among them, Zinc Oxide (ZnO) nanoparticles wangled the reputation of providing "next-generation solutions" and are being utilized in plethora of products. Their widespread application has led to increased exposure of these particles, raising concerns regarding toxicological repercussions to the human health and environment. The diversity, complexity, and heterogeneity in the available literature, along with correlation of befitting attributes, makes it challenging to develop one systematic framework to predict this toxicity. The present study aims at developing predictive modelling framework to tap the prospective features responsible for causing cytotoxicity in-vitro on exposure to ZnO nanoparticles. Rigorous approach was used to mine the information from complete body of evidence published to date. The attributes, features and experimental conditions were systematically extracted to unmask the effect of varied features. 1240 data points from 76 publications were obtained, containing 14 qualitative and quantitative attributes, including physiochemical properties of nanoparticles, cell culture and experimental parameters to perform meta-analysis. For the first time, the efforts were made to investigate the degree of significance of attributes accountable for causing cytotoxicity on exposure to ZnO nanoparticles. We show that in-vitro cytotoxicity is closely related with dose concentration of nanoparticles, followed by exposure time, disease state of the cell line and size of these nanoparticles among other attributes.