Potential Therapeutic Effects of Long-Term Stem Cell Administration: Impact on the Gene Profile and Kidney Function of PKD/Mhm (Cy/+) Rats

Abstract

Cystic kidney disease (CKD) is a heterogeneous group of genetic disorders and one of the most common causes of end-stage renal disease. Here, we investigate the potential effects of long-term human stem cell treatment on kidney function and the gene expression profile of PKD/Mhm (Cy/+) rats. Human adipose-derived stromal cells (ASC) and human skin-derived ABCB5⁺ stromal cells (2 × 10⁶) were infused intravenously or intraperitoneally monthly, over 6 months. Additionally, ASC and ABCB5⁺-derived conditioned media were administrated intraperitoneally. The gene expression profile results showed a significant reprogramming of metabolism-related pathways along with downregulation of the cAMP, NF-kB and apoptosis pathways. During the experimental period, we measured the principal renal parameters as well as renal function using an innovative non-invasive transcutaneous device. All together, these analyses show a moderate amelioration of renal function in the ABCB5⁺ and ASC-treated groups. Additionally, ABCB5⁺ and ASC-derived conditioned media treatments lead to milder but still promising improvements. Even though further analyses have to be performed, the preliminary results obtained in this study can lay the foundations for a novel therapeutic approach with the application of cell-based therapy in CKD.

Keywords: ABCB5; adipose-derived stromal cell (ASC); conditioned media; cystic kidney disease (CKD); gene expression profile.

Figure 1

GSEA analysis using KEGG database. Principal upregulated pathways in i.v. ABCB5⁺; i.p. ABCB5⁺; ABCB5⁺−derived CoCM⁺; i.v. ASC groups; i.p. ASC and ASC−derived CM groups. Significantly (adj. p < 0.05) differentially expressed pathways (PKD/Mhm (Cy/+) + treatment vs. PKD/Mhm (Cy/+)). Data are sorted by main categories. Normalized enrichment score (NES) is given for each pathway.

Figure 2

GSEA analysis using KEGG database. Principal downregulated pathways in i.v. ABCB5⁺; i.p. ABCB5⁺; ABCB5⁺—derived CoCM⁺; i.v. ASC groups; i.p. ASC and ASC—derived CM groups. Significantly (adj. p < 0.05) differentially expressed pathways (PKD/Mhm (Cy/+) + treatment vs. PKD/Mhm (Cy/+)). Data are sorted by main categories. NES is given for each pathway.

Figure 3

Haematoxylin and eosin (H&E) staining of PKD/Mhm (Cy/+) rat kidneys. Altered renal morphology in (A) PKD/Mhm (Cy/+) rat and (B) corresponding magnification of cyst details (red square); (C) ABCB5⁺-derived CoCM⁺ treated rat and (D) corresponding magnification of cyst details; (E) ASC-derived CM-treated rat and (F) corresponding magnification of cyst details; (G) i.p. ABCB5⁺-treated rat and (H) corresponding magnification of cyst details; (I) i.p. ASC-treated rat and (J) corresponding magnification of cyst details; (K) i.v. ABCB5⁺-treated rat and (L) corresponding magnification of cyst details; (M) i.v. ASC-treated rat and (N) corresponding magnification of cyst details. Images acquired with Axio Scan.Z1 microscope (ZEISS), 20× objective; (B,D,F,H,J,L,N) are zoomed in images of the area used to check the size of the scale bar.

Figure 4

Histological changes in PKD/Mhm (Cy/+) rats after treatments (n = 6 in each group). Changes in cyst number (A), percentage (%) of cyst area (B), Tunel-positive cells (C) and Ki67-positive cells (D). Histograms show means ± Std.Dev. * p < 0.05, ** p < 0.005.

Figure 5

Effect of different treatments on renal function parameters in the PKD/Mhm (Cy/+) model (n = 6 in each group). Changes in plasma creatinine (A) and urea (B) concentrations, and in ABZWCY-HβCD half-life (t_1/2) (C). Histograms show means ± Std.Dev. * p < 0.05.

Figure 6

Effect of different treatments on urine parameters in the PKD/Mhm (Cy/+) model (n = 6 in each group). Changes in urine albumin (A) and protein (B) concentrations. Histograms show means ± Std.Dev.