Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are persistent environmental pollutants, raising concerns due to their widespread presence and disruptive biological effects. These compounds are highly stable, allowing them to bioaccumulate in the environment and living organisms, potentially impacting critical physiological functions such as hormonal balance, immune response, and increasing cancer risk. Despite regulatory restrictions, their pervasive nature necessitates further research into their potential effects on cellular and neuronal function. This study first evaluated the cytotoxic effects of PFOS and PFOA on S1 neuroblastoma cells; a dose-dependent reduction in cell viability was revealed for PFOS, while PFOA exhibited minimal toxicity until millimolar concentrations. We further investigated their potential to modulate GABAergic neurotransmission using patch-clamp electrophysiology. Both PFOS and PFOA caused a significant but reversible reduction in GABA receptor-mediated currents following one-minute pre-treatment. These findings suggest that PFOS and PFOA can interfere with both cellular viability and GABAergic signaling, providing critical insights into their functional impacts and highlighting the need for further investigation into the long-term consequences of PFAS exposure on nervous system health.
26 June 2020 in Physical Chemistry Chemical Physics
A distinct set of channels and transporters regulates the ion fluxes across the lysosomal membrane. Malfunctioning of these transport proteins and the resulting ionic imbalance is involved in various human diseases, such as lysosomal storage disorders, cancer, as well as metabolic and neurodegenerative diseases. As a consequence, these proteins have stimulated strong interest for their suitability as possible drug targets. A detailed functional characterization of many lysosomal channels and transporters is lacking, mainly due to technical difficulties in applying the standard patch-clamp technique to these small intracellular compartments. In this review, we focus on current methods used to unravel the functional properties of lysosomal ion channels and transporters, stressing their advantages and disadvantages and evaluating their fields of applicability.
Two-pore channel 2 (TPC2) is a member of the endolysosomal ion channel family, playing critical roles in intracellular calcium signaling and endomembrane dynamics. This review provides an in-depth analysis of TPC2, covering its structural and functional properties, physiological roles, and involvement in human diseases. We discuss current experimental approaches to studying TPC2, including heterologous expression in plant vacuoles and computational modeling strategies. Particular emphasis is placed on the structural determinants of ion permeation, with a focus on the selectivity filter and the central cavity’s influence on channel kinetics. Furthermore, we explore emerging roles of TPC2 in viral infections, particularly SARS-CoV-2, and in cancer, including melanoma progression and neoangiogenesis. The inhibitory potential of natural compounds, such as naringenin, is also examined. By offering a comprehensive overview of current knowledge and methodologies, this review underscores the potential of TPC2 as a promising pharmacological target in both infectious and neoplastic diseases.