Glutamine/glutamate metabolism rewiring in reprogrammed human hepatocyte-like cells

Abstract

Human dermal fibroblasts can be reprogrammed into hepatocyte-like (HEP-L) cells by the expression of a set of transcription factors. Yet, the metabolic rewiring suffered by reprogrammed fibroblasts remains largely unknown. Here we report, using stable isotope-resolved metabolic analysis in combination with metabolomic-lipidomic approaches that HEP-L cells mirrors glutamine/glutamate metabolism in primary cultured human hepatocytes that is very different from parental human fibroblasts. HEP-L cells diverge glutamine from multiple metabolic pathways into deamidation and glutamate secretion, just like periportal hepatocytes do. Exceptionally, glutamine contribution to lipogenic acetyl-CoA through reductive carboxylation is increased in HEP-L cells, recapitulating that of primary cultured human hepatocytes. These changes can be explained by transcriptomic rearrangements of genes involved in glutamine/glutamate metabolism. Although metabolic changes in HEP-L cells are in line with reprogramming towards the hepatocyte lineage, our conclusions are limited by the fact that HEP-L cells generated do not display a complete mature phenotype. Nevertheless, our findings are the first to characterize metabolic adaptation in HEP-L cells that could ultimately be targeted to improve fibroblasts direct reprogramming to HEP-L cells.

Multiple functions of reversine on the biological characteristics of sheep fibroblasts

“…6 F). The detoxification of ammonia into urea and the expression of albumin (ALB) protein are the main characteristics for hepatocytes 28 . Compared with the negative control, the levels of urea and ALB in induced fibroblasts were significantly increased in a time-dependent manner ( p < 0.01, Fig.…”

Excessive gluconeogenesis causes the hepatic insulin resistance paradox and its sequelae

“…Most cell types including human hepatocytes and hepatocyte-like cells also metabolize glutamine to produce fatty acids through the reductive carboxylation of 2-oxoglutarate to produce isocitrate, which is then converted via citrate to acetyl-CoA ( Figure 3 ) [ 82 , 89 , 90 ]. Such glutamine metabolism involving reductive carboxylation of 2-oxoglutarate is a major contributor to hepatic fatty acid synthesis even in healthy individuals [ 91 ].…”

Derivation of healthy hepatocyte-like cells from a female patient with ornithine transcarbamylase deficiency through X-inactivation selection

“…2 A). Reprogrammed cells activated multiple hepatocyte markers, except GLUL which is down-regulated as expected 22 . However, genes characteristic of a fully differentiated hepatocyte such as HPD or CYP3A4, were not within the range of the human liver.…”

“…Clonal HDF LT were reprogrammed to iHEP LT using a protocol adapted from 20 , 22 . HDF LT (18 × 10 3 cells) were seeded on collagen coated plates and infected with equal amounts of 12x concentrated lentiviral vectors encoding HNF4A, HNF1A and FOXA3.…”