Massey Documents by Type

Permanent URI for this communityhttps://mro.massey.ac.nz/handle/10179/294

Browse

Filters

2023 - 20242

Settings

Author: search.filters.author.Mallard BLHas files: Yes

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Impact of Gut Recolonization on Liver Regeneration: Hepatic Matrisome Gene Expression after Partial Hepatectomy in Mice.
    (MDPI (Basel, Switzerland), 2023-06-28) Amin AR; Hairulhisyam NM; Aqilah RNF; Nur Fariha MM; Mallard BL; Shanahan F; Wheatley AM; Marlini M; Neuman M; Malnick S
    The hepatic matrisome is involved in the remodeling phase of liver regeneration. As the gut microbiota has been implicated in liver regeneration, we investigated its role in liver regeneration focusing on gene expression of the hepatic matrisome after partial hepatectomy (PHx) in germ-free (GF) mice, and in GF mice reconstituted with normal gut microbiota (XGF). Liver mass restoration, hepatocyte proliferation, and immune response were assessed following 70% PHx. Hepatic matrisome and collagen gene expression were also analyzed. Reduced liver weight/body weight ratio, mitotic count, and hepatocyte proliferative index at 72 h post PHx in GF mice were preceded by reduced expression of cytokine receptor genes Tnfrsf1a and Il6ra, and Hgf gene at 3 h post PHx. In XGF mice, these indices were significantly higher than in GF mice, and similar to that of control mice, indicating normal liver regeneration. Differentially expressed genes (DEGs) of the matrisome were lower in GF compared to XGF mice at both 3 h and 72 h post PHx. GF mice also demonstrated lower collagen expression, with significantly lower expression of Col1a1, Col1a2, Col5a1, and Col6a2 compared to WT mice at 72 h post PHx. In conclusion, enhanced liver regeneration and matrisome expression in XGF mice suggests that interaction of the gut microbiota and matrisome may play a significant role in the regulation of hepatic remodeling during the regenerative process.
  • Thumbnail Image
    Item
    Hepatotoxicity of titanium dioxide nanoparticles.
    (John Wiley & Sons Ltd, 2024-05-13) Khan J; Kim ND; Bromhead C; Truman P; Kruger MC; Mallard BL
    The food additive E171 (titanium dioxide, TiO2), is widely used in foods, pharmaceuticals and cosmetics. It is a fine white powder, with at least one third of its particles sized in the nanoparticulate (˂100 nm range, TiO2 NPs). The use of E171 is controversial as its relevant risk assessment has never been satisfactorily accomplished. In vitro and in vivo studies have shown dose-dependent toxicity in various organs including the liver. TiO2 NPs have been shown to induce inflammation, cell death and structural and functional changes within the liver. The toxicity of TiO2 NPs in experimental models varies between organs and according to their physiochemical characteristics and parameters such as dosage and route of administration. Among these factors, ingestion is the most significant exposure route, and the liver is a key target organ. The aim of this review is to highlight the reported adverse effects of orally administered TiO2 NPs on the liver and to discuss the controversial state of its toxicity.