Supplementary Material for: The value of diffusion kurtosis imaging to assess liver and kidney recovery after mesenchymal stem cell intervention in CCl4-induced cirrhotic rats

Objective: To investigate the potential of diffusion kurtosis imaging (DKI) in monitoring the improvement of liver and kidney injury in cirrhotic rats after bone marrow derived mesenchymal stem cells (BMSCs) treatment.

Methods: Thirty rats were induced with liver cirrhosis via subcutaneous injection of carbon tetrachloride. Six rats were randomly selected for DKI scanning and subsequently euthanized for biochemical and histological analysis. The remaining 24 rats were randomly divided into a BMSC group (n=12) and control group (n=12). In the BMSC group, six rats underwent dynamic DKI scans and were sacrificed after 13, 14, 15, and 16 weeks, while the other 6 rats were sacrificed after being scanned in the 14th week. The control group followed the same protocol as the BMSC group. Additionally, six normal rats were euthanized after undergoing DKI scanning to provide baseline data. Liver and kidney DKI parameters, biochemical markers, liver fibers, kidney hematoxylin-eosin (HE) score, and alpha smooth muscle actin (α-SMA) were analyzed.

Results: Compared to baseline, there was a significant increase in liver fibers and kidney HE scores by week 12. At weeks 13, 14, 15,and 16, the mean kurtosis (MK) of the liver in the BMSC group was significantly lower than that at week 12 and in the control group. At week 16, the mean diffusion (MD) in the BMSC group was significantly higher than that at week 12 and in the control group. The apparent diffusivity coefficient (ADC) values in the BMSC group were higher than those at week 12 and in the control group at weeks 13, 14, and 16. All regions of kidney showed decreased MK values from weeks 14 to 16 compared to week 12 and the control group. Liver fiber was moderately or highly correlated with all DKI parameters. MK and ADC of the renal cortex (CO) and outer stripe of the outer medulla (OSOM) showed moderate correlation with HE scores and α-SMA.
Conclusion: DKI can serve as a non-invasive means to effectively monitor the process of liver and kidney injury improvement in cirrhotic rats treated with BMSCs.