GEOapplication/xmlftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE294nnn/GSE294004/primaryOK200TranscriptomicsHomo sapiensExpression profiling by high throughput sequencinghttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE294004GEOGSEfalseEffects of Human Plasma-Like Medium on hPSC-derived cardiomyocytes in vitroMaturing hPSC-CMs in vitro is critical for advancing drug discovery and cardiotoxicity screening. However, widely used basal medium such as RPMI contain non-physiological compositions that limit their relevance to human cardiac physiology. In this study we introduced Human Plasma-Like Medium (HPLM) as a better basal medium supplemented with B27, a physiologically tailored alternative designed to systematically replicate the salt concentrations and polar metabolite profiles of adult human plasma. Starting with Day16 hPSC-CMs, we cultured cells for two weeks in HPLM/B27 or control media (standard and low-glucose [5 mM] RPMI/B27) and assessed maturation outcomes at Day30. Compared to standard and low-glucose RPMI/B27, HPLM/B27 significantly enhanced hPSC-CM maturity across transcriptomic, structural, functional, and metabolic aspects. These improvements included accomplished myosin heavy chain isoform switching (MYH6 to MYH7), accelerated ventricular-specific myosin light chain isoform switching (MLC2a to MLC2v), elongated sarcomeres (~2.07 µm), enhanced calcium transient kinetics, and coordinated activation of oxidative and glycolytic metabolism. Collectively, these findings establish HPLM as a better basal medium than low glucose RPMI for driving cardiomyocyte maturation in vitro.2026/04/02GSE294004GSM8896241GSM8896240GSM8896243GSM8896242GSM8896234GSM8896245GSM8896244GSM8896233GSM8896247GSM8896236GSM8896246GSM8896235GSM8896238GSM8896237GSM8896248GSM889623924676294004Homo sapiens