Diabetic Kidney Disease Alters the Transcriptome and Function of Human Adipose-Derived Mesenchymal Stromal Cells but Maintains Immunomodulatory and Paracrine Activities Important for Renal Repair

Abstract

Mesenchymal stem/stromal cells (MSCs) facilitate repair in experimental diabetic kidney disease (DKD). However, the hyperglycemic and uremic milieu may diminish regenerative capacity of patient-derived therapy. We hypothesized that DKD reduces human MSC paracrine function. Adipose-derived MSC from 38 participants with DKD and 16 control subjects were assessed for cell surface markers, trilineage differentiation, RNA sequencing (RNA-seq), in vitro function (coculture or conditioned medium experiments with T cells and human kidney cells [HK-2]), secretome profile, and cellular senescence abundance. The direction of association between MSC function and patient characteristics were also tested. RNA-seq analysis identified 353 differentially expressed genes and downregulation of several immunomodulatory genes/pathways in DKD-MSC versus Control-MSC. DKD-MSC phenotype, differentiation, and tube formation capacity were preserved, but migration was reduced. DKD-MSC with and without interferon-γ priming inhibited T-cell proliferation greater than Control-MSC. DKD-MSC medium contained higher levels of anti-inflammatory cytokines (indoleamine 2,3-deoxygenase 1 and prostaglandin-E2) and prorepair factors (hepatocyte growth factor and stromal cell–derived factor 1) but lower IL-6 versus control-MSC medium. DKD-MSC medium protected high glucose plus transforming growth factor-β–exposed HK-2 cells by reducing apoptotic, fibrotic, and inflammatory marker expression. Few DKD-MSC functions were affected by patient characteristics, including age, sex, BMI, hemoglobin A1c, kidney function, and urine albumin excretion. However, senescence-associated β-galactosidase activity was lower in DKD-MSC from participants on metformin therapy. Therefore, while DKD altered the transcriptome and migratory function of culture-expanded MSCs, DKD-MSC functionality, trophic factor secretion, and immunomodulatory activities contributing to repair remained intact. These observations support testing of patient-derived MSC therapy and may inform preconditioning regimens in DKD clinical trials.

Strategies for targeting senescent cells in human disease

“…This modern wave of attention was promoted by the discoveries that markers of cellular senescence accumulate with aging and accumulation is delayed by interventions that increase healthspan and lifespan 31 , removal of senescent cells increases healthspan in progeroid mouse models 32 , and transplantation of a relatively small number of senescent cells into previously healthy animals provokes multisystem dysfunction similar to what is seen in aged animals 33,34 . Furthermore, it was found that the correlation of senescent cell accumulation with disease extends to humans [35][36][37] , and that senescent cell burden can be safely reduced in a clinical context 38 . On the basis of these points, it appears crucial to understand the roles of senescence in morbidity and mortality.…”

A Systematic Review and Meta-Analysis of Cell-Based Interventions in Experimental Diabetic Kidney Disease

“…Uniquely, the low immunogenic properties of MSC and other cells/products permitted successful studies in xenotransplantation[92][93][94][95] Interestingly, xenotransplantation yielded greater reduction in urea and proteinuria compared to the within-species groups. Our study also determined that disease-source cells sufficiently induced renal repair 45. Specifically, Zhang et al50 found that disease-source compared to healthy early outgrowth BM cells were equally effective in reducing glomerular/interstitial fibrosis and oxidative stress.…”

“…Second, exploitation of stem cell paracrine-mediated activities using cell-derived products, such as extracellular vesicles and conditioned medium, has not been fully explored. 22,[39][40][41][42] Third, the pro-apoptotic, DKD microenvironment reduces stem cell function and vitality, 11,[43][44][45] thus novel preconditioning strategies and alternative delivery methods are being actively pursued. 21,22,32,34,[46][47][48][49][50][51] Fourth, feasibility of cells harvested from diseased (autologous) host sources requires additional testing.…”

“…21,22,32,34,[46][47][48][49][50][51] Fourth, feasibility of cells harvested from diseased (autologous) host sources requires additional testing. 35,45,46,50 Each of these treatment-related factors may influence effects of cell-based therapy on kidney outcomes. The current pool of available studies now affords an opportunity to summarize the effect of cell-based therapy in experimental models of DKD and gain better understanding of how treatment-related factors may influence DKD outcomes.…”

Equilibrium among Inflammatory Factors Determines Human MSC-Mediated Immunosuppressive Effect

“…Our findings, which reveal the upregulation of IL-1, IL-6, IL-8, IFN-γ, MCP-1, and G-CSF in MSC and PBMC co-cultures, highlight a potential area to search for inducers of MSC therapeutic activity. Currently, there is strong evidence that preconditioning with IFN-γ enhances the immunomodulatory properties and therapeutic efficacy of MSCs by promoting the expression of IDO [ 53 , 54 , 55 , 56 , 57 , 58 ]. On the other hand, it has been reported that stimulation of MSCs through the NF-κB pathway can also induce some synergistic and overlapping functionalities with integrative effects.…”