TY - JOUR
T1 - The effects of maturation and aging on the rotator cuff tendon-to-bone interface
AU - Jiang, Xiping
AU - Wojtkiewicz, Melinda
AU - Patwardhan, Chinmay
AU - Greer, Sydney
AU - Kong, Yunfan
AU - Kuss, Mitchell
AU - Huang, Xi
AU - Liao, Jun
AU - Lu, Yongfeng
AU - Dudley, Andrew
AU - Gundry, Rebekah L.
AU - Fuchs, Matthias
AU - Streubel, Philipp
AU - Duan, Bin
N1 - Publisher Copyright:
© 2021 Federation of American Societies for Experimental Biology
PY - 2021/12
Y1 - 2021/12
N2 - Rotator cuff tendon injuries often occur at the tendon-to-bone interface (i.e., enthesis) area, with a high prevalence for the elderly population, but the underlying reason for this phenomenon is still unknown. The objective of this study is to identify the histological, molecular, and biomechanical alterations of the rotator cuff enthesis with maturation and aging in a mouse model. Four different age groups of mice (newborn, young, adult, and old) were studied. Striking variations of the entheses were observed between the newborn and other matured groups, with collagen content, proteoglycan deposition, collagen fiber dispersion was significantly higher in the newborn group. The compositional and histological features of young, adult, and old groups did not show significant differences, except having increased proteoglycan deposition and thinner collagen fibers at the insertion sites in the old group. Nanoindentation testing showed that the old group had a smaller compressive modulus at the insertion site when compared with other groups. However, tensile mechanical testing reported that the old group demonstrated a significantly higher failure stress when compared with the young and adult groups. The proteomics analysis detected dramatic differences in protein content between newborn and young groups but minor changes among young, adult, and old groups. These results demonstrated: (1) the significant alterations of the enthesis composition and structure occur from the newborn to the young time period; (2) the increased risk of rotator cuff tendon injuries in the elderly population is not solely because of old age alone in the rodent model.
AB - Rotator cuff tendon injuries often occur at the tendon-to-bone interface (i.e., enthesis) area, with a high prevalence for the elderly population, but the underlying reason for this phenomenon is still unknown. The objective of this study is to identify the histological, molecular, and biomechanical alterations of the rotator cuff enthesis with maturation and aging in a mouse model. Four different age groups of mice (newborn, young, adult, and old) were studied. Striking variations of the entheses were observed between the newborn and other matured groups, with collagen content, proteoglycan deposition, collagen fiber dispersion was significantly higher in the newborn group. The compositional and histological features of young, adult, and old groups did not show significant differences, except having increased proteoglycan deposition and thinner collagen fibers at the insertion sites in the old group. Nanoindentation testing showed that the old group had a smaller compressive modulus at the insertion site when compared with other groups. However, tensile mechanical testing reported that the old group demonstrated a significantly higher failure stress when compared with the young and adult groups. The proteomics analysis detected dramatic differences in protein content between newborn and young groups but minor changes among young, adult, and old groups. These results demonstrated: (1) the significant alterations of the enthesis composition and structure occur from the newborn to the young time period; (2) the increased risk of rotator cuff tendon injuries in the elderly population is not solely because of old age alone in the rodent model.
KW - age
KW - biomechanical properties
KW - enthesis
KW - nanoindentation
KW - proteomics
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U2 - 10.1096/fj.202101484R
DO - 10.1096/fj.202101484R
M3 - Article
C2 - 34822203
AN - SCOPUS:85120654522
SN - 0892-6638
VL - 35
JO - FASEB Journal
JF - FASEB Journal
IS - 12
M1 - e22066
ER -