Research Paper|Volume 12, Issue 17|pp 16899—16920

Umbilical cord mesenchymal stem cells protect thymus structure and function in aged C57 mice by downregulating aging-related genes and upregulating autophagy- and anti-oxidative stress-related genes

Xing-Hua Pan^1,^2,³, Qing-Keng Lin^1,^2,³, Xiang Yao^1,^2,³, Zi-An Li^1,^2,³, Xue-Min Cai^1,^2,³, Rong-Qing Pang^1,^2,³, Guang-Ping Ruan^1,^2,³

¹Kunming Key Laboratory of Stem Cell and Regenerative Medicine, 920th Hospital of The PLA Joint Logistics Support Force, Kunming, Yunnan Province, China
²Stem Cell and Immune Cell Biomedical Techniques Integrated Engineering Laboratory of States and Regions, Kunming, Yunnan Province, China
³Cell Therapy Technology Transfer Medical Key Laboratory of Yunnan Province, Kunming, Yunnan Province, China

Received: January 20, 2020Accepted: June 13, 2020Published: September 14, 2020

https://doi.org/10.18632/aging.103594

Copyright: © 2020 Pan et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Abstract

Background: To study the effect of allogeneic umbilical cord mesenchymal stem cell transplantation on the structure and function of the thymus in aged C57 mice and provide a new method for the treatment of senile thymic atrophy.

Results: The changes in the thymus cortex and medulla volume and the lymphocyte ratio were analyzed by immunofluorescence. For thymus tissue sections, immunohistochemical staining was performed to detect p16, p53, SOD, becline1, LC3b, p62, sirt1, and sirt3. Changes in CK5, CK8, CD4 and CD8 expression were observed. Treatment with mUCMSCs could promote hair regeneration in aging mice and regenerate the thymus structure.

Conclusions: mUCMSCs inhibited senescence of the thymus and promoted structural and functional thymus regeneration by downregulating the senescence genes p53 and p16 and upregulating the SOD, Sirt1 and Sirt3 genes, but the mechanism requires further research.

Methods: C57 mice were obtained and met the requirements of thymic aging. mUCMSCs were infused via the tail vein at a dose of 1×10⁷ cells/kg twice per week for 3 weeks. Six weeks after the last transplantation, the thymus was weighed, and the thymus-to-body weight ratio was calculated. The thymus tissue was stained with HE.