Dose-Dependent Paradoxical Effect of Multi-Wall Carbon Nanotube on Hepatocyte

Abstract

Biomedical applications of carbon nanotubes often faced serious criticism because of its nanotoxicity. Its been observed that CNT showed hepatotoxicity in vitro at the concentration above 20µg/ml but its effect on liver cells at lower concentrations is not yet explored. Here, we performed a detailed study to evaluate the dose-dependent response of hepatocytes against CNT. For this purpose hepatocytes cell line (HepG2) were treated with multi-wall CNT (MWCNT) of different concentration ranging 100µg/ml to 10ng/ml. MWCNT at a concentration of 100µg/ml showed hepatotoxicity but at lower concentrations, it stimulate cell proliferation. LDH assay revealed that MWCNT at higher concentration caused significant damage to the cell membrane but at lower concentration, it fails to do so. It was observed that MWCNT at lower concentration increases production of albumin, ATP7B and SULT2A1. Density of bile canaliculi in HepG2 cells also increased after treatment. These studies altogether suggest that although MWCNT showed hepatotoxicity at higher concentration, it can work as a mitogen at a lower concentration.