Defects in energy metabolism are associated with functional exhaustion of bone marrow mesenchymal stem cells in cirrhosis.

OBJECTIVES

Cellular and functional exhaustion of bone marrow mesenchymal stem cells (BM-MSC) is significantly associated with the loss of HSCs and hepatic osteodystrophy in cirrhosis. The molecular mechanisms underlying the dysfunction of BM-MSCs are not well understood. We investigated the underlying mechanisms of cellular and functional exhaustion of BM-MSCs in cirrhosis.

METHODS

The MSCs were isolated retrospectively from bone marrow of decompensated alcoholic cirrhosis patients {(Trial registration: ClinicalTrials.gov NCT01902511) (n=10; MELD=16.2±2.3; CTP=8.7±2.3)} and age and gender-matched healthy controls (n=8). Global gene expression profile of healthy bone marrow MSCs (hBM-MSCs) and cirrhosis patients BM-MSCs (cBM-MSCs) were done by mRNA sequencing. XFe24-bioanalyzer analyzed the bioenergetic potential of cells. Level of different cytokines and growth factors in BM-plasma and MSCs secretome were analyzed by Luminex-based bead array.

RESULTS

Analysis of differentially expressed genes showed significant (P<0.01) up-regulation of genes associated with ubiquitination and catabolism of proteins; TNF signaling, insulin resistance, and down-regulation of genes associated with DNA repair, protein processing, cell cycle, and mitochondrial respiration in cBM-MSCs in comparison to hBM-MSCs. Compared to hBM-MSCs, cBM-MSCs showed a significant defect in glycolysis due to insulin resistance and poor glucose uptake (P=0.002). This led to compromised self-renewal capacity and cellular loss of MSCs in cirrhosis. cBM-MSCs also showed a significant impairment in Oxidative phosphorylation (OXPHOS) due to mitochondrial dysfunction leading to defects in the osteogenic differentiation with early aging and senescence.

CONCLUSION

Compromised energy metabolism due to inflammatory and metabolic stress-induced insulin resistance underlies the cellular and functional exhaustion of BM-MSCs in cirrhosis.