Aflatoxins as a risk factor for liver cirrhosis: a systematic review and meta-analysis

Abstract

Background: Liver cirrhosis is characterized by fibrosis and nodule formation in the liver, due to a chronic injury, and subsequent alteration of the normal architecture of the liver. Even though there is a huge effort to elucidate the possible etiologic factors of liver cirrhosis, a significant number of cases are cryptogenic, especially in Sub Saharan Africa, where there is a high burden of aflatoxin exposure. Aflatoxins are known to cause hepatocellular carcinoma, which share similar etiologic factors with liver cirrhosis. This study aimed to assess the association between aflatoxin exposure and the risk of liver cirrhosis. Methods: Relevant studies were identified through systematic searches conducted in Ovid MEDLINE, PubMed and Google Scholar. Also, by searching the references of retrieved articles. The abstracts and full text were screened for eligibility and the risk of bias was assessed for each study using Joanna Briggs Institute (JBI) critical appraisal checklist for observational studies. The extracted data from included studies using Microsoft Excel were exported to Stata software version 15.0 for analyses. The overall pooled estimation of outcomes was calculated using a randomeffects model of DerSimonian-Laird method at a 95% confidence level. The heterogeneity of studies was determined using I2 statistics. The presence of publication bias between studies was evaluated using the Begg's and Egger's tests and funnel plot. The protocol of this systematic review and meta-analysis was registered in the Prospero database with reference number ID: CRD42019148481. Results: A total of 5 studies published between the years 2005 and 2018 that met the pre-defined inclusion and exclusion criteria were included. The meta-analysis showed that a significant increase in the risk of liver cirrhosis is associated with aflatoxin exposure (unadjusted pooled odds ratio (OR) = 3.35, 95% CI: 2.74-4.10, p = 0.000; I 2 = 88.3%, p = 0.000; adjusted OR = 2.5, 95% CI: 1.84-3.39, p = 0.000; I 2 = 0%, p = 0.429). Conclusions: The present meta-analysis suggests that aflatoxin exposure is associated with a higher risk of liver cirrhosis.

An overview of mycotoxin biomarker application in exposome-health studies

“…Some population-based studies have also 8 successfully implemented the mutation of codon 249 of the TP53 gene (249ser TP53) measured in plasma DNA as biomarker resulting from AFB1 exposure, supporting the IARC evaluation [14]. The biomarkers AF-albumin adduct or 249ser TP53 mutation have been also implemented in 5 epidemiological studies from China, Taiwan, India and Gambia on cirrhosis risk, which meta-analysis has revealed positive consistent associations with absence of heterogeneity [15].…”

Mycotoxigenic Genera of Micromycetes Contaminating Food and Feed

“…Chronická toxicita může nastat při dlouhodobém vystavení nízkým dávkám mykotoxinů. Chronickým účinkem některých mykotoxinů je podíl na vyvolání rakoviny (zejména jater), cirhózy jater a dalších onemocnění 10,11 . Ze studií zabývajících se intoxikací aflatoxiny v Indii a Keni ve spojitosti s konzumací kukuřice lze odhadnout hranici příjmu celkových aflatoxinů vedoucí k riziku úmrtí dospělého člověka na >20 μg kg -1 tělesné hmotnosti/den (cit.…”

Fungal Toxins and Host Immune Responses

“…Aflatoxins cause a wide range of toxicoses and predominantly target the liver, resulting in cirrhosis and hepatocellular carcinoma (Newberne and Butler, 1969;Shank et al, 1972;Peers, 1973;Mekuria et al, 2020). Indeed, the mean concentration of free aflatoxin B 1 in the serum of patients with hepatocellular carcinoma was 0.2 nM compared with 0.06 nM in healthy controls (Aydin et al, 2015;Ferri et al, 2017).…”