Title
Culture Conditions that Support Expansion and Chondrogenesis of Middle-Aged Rat Mesenchymal Stem Cells
Publication Date
2018
Journal Title
Cartilage
Abstract
© The Author(s) 2018. Objective: Rats are an early preclinical model for cartilage tissue engineering, and a practical species for investigating the effects of aging. However, rats may be a poor aging model for mesenchymal stem cells (MSCs) based on laboratory reports of a severe decline in chondrogenesis beyond young adulthood. Such testing has not been conducted with MSCs seeded in a scaffold, which can improve the propensity of MSCs to undergo chondrogenesis. Therefore, the objective of this study was to evaluate chondrogenesis of middle-aged rat MSCs encapsulated in agarose. Design: MSCs from 14- to 15-month-old rats were expanded, seeded into agarose, and cultured in chondrogenic medium with or without 5% serum for 15 days. Samples were evaluated for cell viability and cartilaginous extracellular matrix (ECM) accumulation. Experiments were repeated using MSCs from 6-week-old rats. Results: During expansion, middle-aged rat MSCs demonstrated a diminishing proliferation rate that was improved ~2-fold in part by transient exposure to chondrogenic medium. In agarose culture in defined medium, middle-aged rat MSCs accumulated ECM to a much greater extent than negative controls. Serum supplementation improved cell survival ~2-fold, and increased ECM accumulation ~3-fold. Histological analysis indicated that defined medium supported chondrogenesis in a subset of cells, while serum-supplementation increased the frequency of chondrogenic cells. In contrast, young rat MSCs experienced robust chondrogenesis in defined medium that was not improved with serum-supplementation. Conclusions: These data demonstrate a previously-unreported propensity of middle-aged rat MSCs to undergo chondrogenesis, and the potential of serum to enhance chondrogenesis of aging MSCs.
Document Type
Article
Status
Faculty
Facility
School of Medicine
Primary Department
Orthopedic Surgery
Additional Departments
Molecular Medicine; Urology
PMID
DOI
10.1177/1947603518790047