A comparative study on the effects of ammonia on the growth and metabolism of two glioblastoma cell lines probed by NMR spectroscopy*

One of the most lethal and aggressive types of cancer is glioblastoma. Despite the rigorous research regarding this malady, there is still no cure, and survival still does not last long-term. Hence, mimicking glioblastoma in vitro as accurately as possible through cell culture is an important aspect of research to generate reliable results. Ammonia concentration on cell culture media is shown to decrease viability, thwart glucose consumption, heighten reactive oxygen species production, change the morphology of cells, etc. In this study, we investigated how different concentrations of ammonium chloride affect two cell lines of glioblastoma: SfxL and U87. We administered 0mM, 5 mM, and 10 mM of ammonium chloride to both cell lines for 48 hrs. Preliminary trials show highly different results between SfxL and U87. After 24 hrs, SFxL cells metabolized glucose into lactate however, after 48 hrs, the prominent metabolic byproduct was not lactate but acetate, and as the ammonium concentration increased, the lactate peak decreased. Furthermore, alanine peaks were also observed, and they showed a positive relationship with ammonium concentration. On the contrary, U87 after 48 hrs only have a significant increase in lactate production. These preliminary NMR results will be discussed along with the other supporting data. This study is supported by the Welch Foundation grant AT-2111-20220331, US Department of Defense CDMRP grants W81XWH-21-1-0176, W81XWH-22-1-0105, W81XWH-19-1-0741, and W81XWH-22-1-0003.