Ameliorative effect of biosynthesized titanium dioxide nanoparticles using garlic extract on the body weight and developmental toxicity of liver in albino rats compared with chemically synthesized nanoparticles

Abstract

The application of metallic nanoparticles poses risks to human and animal health. Titanium dioxide nanoparticles (TiO₂NPs) are the most commonly synthesized metallic oxides in the world. Exposure to TiO₂NPs can cause toxicity in the target organisms. This study aimed to evaluate the effects of green and chemical TiO₂NPs on maternal and embryo-fetal livers. Green TiO₂NPs using garlic extract (GTiO₂NPs) and chemical TiO₂NPs (CHTiO₂NPs) were synthesized and characterized by x-ray powder diffraction and high-resolution transmission electron microscopy. The cytotoxicity of both chemical and green TiO₂NPs was determined against HepG₂ cell lines. Fifty pregnant female Albino rats were equally and randomly divided into five groups. Group 1 was kept as a control. Groups 2 and 3 were orally treated with 100 and 300 mg/kg body weight of CHTiO₂NPs, respectively. Groups 4 and 5 were orally treated with 100 and 300 mg/kg of GTiO₂NPs, respectively, from day 6 to 19 of gestation. All dams were euthanized on gestation day 20. All live fetuses were weighed and euthanized. Blood and tissue samples were collected for biochemical, histopathological, and Bax-immunohistochemical expression analyses. Our results indicated that garlic could be used as a reducing agent for the synthesis of TiO₂NPs, and the produced NPs have no toxic effect against HepG₂ cells compared with CHTiO₂NPs. The maternal and fetal bodyweights were greatly reduced among the chemically TiO₂NPs induced animals. The mean serum level of AST and ALT activities and the total protein level significantly increased when TiO₂NPs were administered at high doses. Histologically, the CHTiO₂NPs-treated groups revealed vacuolated and necrotized hepatocytes with congested and dilated blood vessels in the fetal and maternal livers. The immunohistochemistry revealed distinct positive staining of Bax expressed in the hepatocytes. Nevertheless, the biosynthesis of TiO₂NPs using garlic extract had a minimal effect on the normal architecture of the liver. It could be concluded that the bioactivity of TiO₂NPs can be modified by green synthesis using garlic extract. Compared to the CHTiO₂NPs, the exposure to GTiO₂NPs showed reduced liver damage in maternal and embryo-fetal rats.

Keywords: Bax-immunohistochemically; TiO2NPs; bodyweight; fetuses; garlic; histology; liver.

Figure 1

XRD pattern combined with HRTEM images of CHTiO₂NPs and GTiO₂NPs.

Figure 2

Cell viability of HepG₂ cells after 24 h exposure to CHTiO₂NPs and GTiO₂NPs with different concentrations and microscopic images of HepG₂ cells after 24 hrs of exposure to CHTiO₂ NPs and GTiO₂NPs at concentration 0.5 mM and 8 mM.

Figure 3

(A,B) Light photomicrograph of sections from the fetal liver of control stained with H&E: control showing intense infiltration of hematopoietic cells, mainly RBCs and lymphocytes in the blood sinusoids (A,B).

Figure 4

(A–D) Light photomicrograph of sections from the fetal liver of CHTiO₂NPs exposed groups. CHTiO₂NPs of 100 mg/kg bwt showing extensive hepatic vacuolation (arrow), thrombotic vasculitis of the central vein, and lymphocyte infiltration (star) (A,B). CHTiO₂NPs of 300 mg/kg bwt show remarkable congestion and dilatation of the blood vessels (C), besides severe necrosis and cytoplasmic vacuolization of the hepatocytes with inflammatory cell infiltration (D).

Figure 5

(A–D) Light photomicrograph of sections from the fetal liver of GTiO₂NPs exposed groups. GTiO₂NPs of 100 mg/kg bwt show slight congestion and dilatation of the central vein (A), in addition to cytoplasmic vacuolation (arrow) and inflammatory cell infiltration (star) (B). GTiO₂NPs of 300 mg/kg bwt show proliferation of the hepatocytes with mitotic division (arrow) in addition to congestion and dilatation of the blood vessels (star) (C,D).

Figure 6

(A,B) Light photomicrograph sections from maternal liver of control group showing normally arranged hepatic cords and blood vessels.

Figure 7

(A–D) Light photomicrograph of sections from the liver of CHTiO₂NPs exposed groups. CHTiO₂NPs of 100 mg/kg bwt show noticeable dilatation of the central vein with perivascular mononuclear infiltration, mostly lymphocytes (arrow), also prominent vacuolation and necrosis of the hepatocytes (star) (A,B). CHTiO₂NPs of 300 mg/kg bwt showed congestion of the central vein and blood sinusoids (C), and portal inflammation and fibrosis were seen (D).

Figure 8

(A–D) Light photomicrograph of sections from the maternal liver of GTiO₂NPs exposed groups. GTiO₂NPs of 100 mg/kg bwt show slight congestion and dilatation of the central vein (arrow), in addition to the regeneration of some hepatocytes (star) (A,B). GTiO₂NPs of 300 mg/kg bwt showing regeneration of the hepatocytes in trial to restore normal histological structures (C,D).

Figure 9

(A–E) Light photomicrograph of sections from the fetal liver of control and other exposed groups by Bax-IHC: control showing negative Bax-immunostaining in the hepatocytes (A). Groups 2 and 3 show intense positive staining reactions of Bax in the hepatocytes (B,C). Group 4 shows negative Bax-immunoreactivity in the hepatocytes (D). Group 5 shows a weak positive Bax-immunoreactivity in the hepatocytes (E).