Cultivation of Cells in a Physiological Plasmax Medium Increases Mitochondrial Respiratory Capacity and Reduces Replication Levels of RNA Viruses

Abstract

Changes in metabolic pathways are often associated with the development of various pathologies including cancer, inflammatory diseases, obesity and metabolic syndrome. Identification of the particular metabolic events that are dysregulated may yield strategies for pharmacologic intervention. However, such studies are hampered by the use of classic cell media that do not reflect the metabolite composition that exists in blood plasma and which cause non-physiological adaptations in cultured cells. In recent years two groups presented media that aim to reflect the composition of human plasma, namely human plasma-like medium (HPLM) and Plasmax. Here we describe that, in four different mammalian cell lines, Plasmax enhances mitochondrial respiration. This is associated with the formation of vast mitochondrial networks and enhanced production of reactive oxygen species (ROS). Interestingly, cells cultivated in Plasmax displayed significantly less lysosomes than when any standard media were used. Finally, cells cultivated in Plasmax support replication of various RNA viruses, such as hepatitis C virus (HCV) influenza A virus (IAV), severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) and several others, albeit at lower levels and with delayed kinetics. In conclusion, studies of metabolism in the context of viral infections, especially those concerning mitochondria, lysosomes, or redox systems, should be performed in Plasmax medium.

Physiological Media in Studies of Cell Metabolism

“…The use of physiologically based media affected the morphology and cell growth rate of some cell lines (as illustrated by the example of the MDA-MB-468 line) and the density of intercellular contacts [ 27 ]. Similar data were obtained by our group for the following cell lines: hepatocarcinoma Huh7.5, cervical cancer HeLa, and kidney of the green monkey Vero E6, which, when cultured in Plasmax medium, became more elongated and formed less dense contacts with each other [ 36 ].…”

“…Physiological culture media affect also mitochondrial respiration (oxidative phosphorylation). We have shown on four different cell lines (Huh7.5, A549, HeLa, and Vero E6) that the replacement of classical media with Plasmax leads to a pronounced increase in the respiratory activity of mitochondria without a noticeable change in their mass [ 36 ]. It is worth noting that different standard culture media were used for each of these lines, i.e., DMEM, DMEM-F12, and MEM.…”

The Effects of H2S and Recombinant Human Hsp70 on Inflammation Induced by SARS and Other Agents In Vitro and In Vivo

“…Total RNA was purified from a conditioned medium 4 days post-infection using the High Pure RNA Isolation Kit (Roche Life Sciences, Schlieren, Switzerland) according to the manufacturer’s instructions. Reverse transcription and quantification of SARS-CoV-2 genomic RNA were performed as described in [ 38 ].…”

An overview of “Chronic viral infection and cancer, openings for vaccines” virtual symposium of the TechVac Network - December 16-17, 2021

“…The results strongly support that studies of metabolic changes in virusinfected cells, especially of those involving mitochondria, lysosomes, or redox systems, should be performed in physiological medium. Results presented by Golikov have been lately published in Antioxidants (Bazel) [3].…”

“…2 Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden. 3 Peoples Friendship University of Russia (RUDN University), Moscow, Russia. 4…”