Determination of Perflourooctanoic Acid Toxicity in a Human Hepatocarcinoma Cell Line

Background. Perfluorooctanoic acid (PFOA) is used in different industrial and commercial products. Research shows the presence of PFOA in home dusts, tap and surface water, and in biological samples. The International Agency for Research on Cancer (IARC) has classified PFOA as a possible carcinogen for humans. The liver is thought to be a target organ of PFOA accumulation and toxicity. Objective. Some studies have found toxic effects on the liver and related mechanisms; however, more studies are needed to better understand PFOA - induced hepatotoxicity. Methods. In the present study, a human hepatocarcinoma cell line was exposed to PFOA for 24 hours and cell viability, apoptosis, the oxidative system and immune response were evaluated. Results. While apoptosis was the main cell death pathway at low concentration (86.5%), the necrotic cell fraction increased with higher concentrations (46.7%). Significant changes in the reactive oxygen species (5.3-folds) glutathione (GSH) (1.7-folds) and catalase (CAT) (1.4-folds) levels were observed, as well as changes to interleukin-6 (≤1.8-fold) and interleukin-8 levels (35–40%). Conclusions. In light of the data, PFOA is potentially hepatotoxic through the investigated pathways. The results represent a background for future in vivo mechanistic studies. Competing Interests. The authors declare no competing financial interests.

Boric acid toxicity in some selected molluscan species

: Survivability of animals is correlated with their fecundity and fertility success. Widespread use of enormous organic and inorganic ingredients as pesticides, molluscicides and insecticides contaminate ecosystems leading to hazardous effects on the life cycle of animals, their biological processes and reproduction. Present work aimed for toxicity assessment of boric acid against some selected molluscan species through evaluation of their mortality by determination of LC50. For toxicity assessment three different molluscan species were used. By applying standard procedure, LC50 was estimated at different concentrations of boric acid for different exposure periods. This study indicated that freshwater snail Bellamya bengalensis was more sensitive for boric acid, whereas slug, Semperula maculate was least sensitive against boric acid after different period of exposure.

Managing valproic acid toxicity-related hyperammonaemia: an unpredicted course

A 20-year-old woman presented following an intentional overdose of valproic acid. Use of valproic acid, either acute or chronic, can result in hyperammonaemia. Mild hyperammonaemia with chronic use is mostly asymptomatic but can also present with concern for encephalopathy. Acute valproic acid toxicity results in significant hyperammonaemia, which can contribute to encephalopathy. Levocarnitine is the treatment of choice in valproic acid toxicity-related hyperammonaemia. For severe cases of encephalopathy, intermittent haemodialysis can also be considered. To our knowledge, this is the first case report to clearly show symptom relapse and hyperammonaemia after discontinuing levocarnitine. We recommend levocarnitine therapy for at least 72 hours, followed by an additional 24 hours of monitoring for symptom relapse and hyperammonaemia after levocarnitine discontinuation.

Analysis of the response of the cell membrane of Saccharomyces cerevisiae during the detoxification of common lignocellulosic inhibitors

Gaining an in-depth understanding of the response of Saccharomyces cerevisiae to the different inhibitors generated during the pretreatment of lignocellulosic material is driving the development of new strains with higher inhibitor tolerances. The objective of this study is to assess, using flow cytometry, how three common inhibitors (vanillin, furfural, and acetic acid) affect the membrane potential, the membrane permeability and the concentration of reactive oxygen species (ROS) during the different fermentations. The membrane potential decreased during the detoxification phase and reflected on the different mechanisms of the toxicity of the inhibitors. While vanillin and furfural caused a metabolic inhibition and a gradual depolarization, acetic acid toxicity was related to fast acidification of the cytosol, causing an immediate depolarization. In the absence of acetic acid, ethanol increased membrane permeability, indicating a possible acquired tolerance to ethanol due to an adaptive response to acetic acid. The intracellular ROS concentration also increased in the presence of the inhibitors, indicating oxidative stress. Measuring these features with flow cytometry allows a real-time assessment of the stress of a cell culture, which can be used in the development of new yeast strains and to design new propagation strategies to pre-adapt the cell cultures to the inhibitors.