TY - JOUR
T1 - Infrapatellar Fat Pad Gene Expression and Protein Production in Patients with and without Osteoarthritis
AU - Belluzzi, Elisa
AU - Macchi, Veronica
AU - Fontanella, Chiara Giulia
AU - Carniel, Emanuele Luigi
AU - Olivotto, Eleonora
AU - Filardo, Giuseppe
AU - Sarasin, Gloria
AU - Porzionato, Andrea
AU - Granzotto, Marnie
AU - Pozzuoli, Assunta
AU - Berizzi, Antonio
AU - Scioni, Manuela
AU - Caro, Raffaele De
AU - Ruggieri, Pietro
AU - Vettor, Roberto
AU - Ramonda, Roberta
AU - Rossato, Marco
AU - Favero, Marta
PY - 2020/8/21
Y1 - 2020/8/21
N2 - Osteoarthritis (OA) is one of the most common joint disorders. Evidence suggests that the infrapatellar fat pad (IFP) is directly involved in OA pathology. However, a comparison between OA versus non-OA IFP is still missing. Thus, the aim of this study was to compare IFP molecular, adipocytes and extracellular matrix characteristics of patients affected by OA, and patients undergoing anterior cruciate ligament (ACL) reconstruction. We hypothesized that not only inflammation but also changes in adipocytes and extracellular matrix (ECM) composition might be involved in OA pathogenesis. Fifty-three patients were enrolled. IFP biopsies were obtained, evaluating: (a) lymphocytic infiltration and vascularization; (b) adipocytes area and number; (c) adipo-cytokines and extracellular matrix gene expression levels; (d) IL-6 and VEGF protein production; (e) collagen fibers distribution. OA IFP was more inflamed and vascularized compared to ACL IFP. OA IFP adipocytes were larger and numerically lower (1.3-fold) than ACL IFP adipocytes. An increase of gene expression of typical white adipose tissue genes was observed in OA compared to ACL IFP. Collagen-types distribution was different in the OA IFP group compared to controls, possibly explaining the change of the biomechanical characteristics found in OA IFP. Statistical linear models revealed that the adipocyte area correlated with BMI in the OA group. In conclusion, inflammation and fibrotic changes of OA IFP could represent novel therapeutic targets to counteract OA.
AB - Osteoarthritis (OA) is one of the most common joint disorders. Evidence suggests that the infrapatellar fat pad (IFP) is directly involved in OA pathology. However, a comparison between OA versus non-OA IFP is still missing. Thus, the aim of this study was to compare IFP molecular, adipocytes and extracellular matrix characteristics of patients affected by OA, and patients undergoing anterior cruciate ligament (ACL) reconstruction. We hypothesized that not only inflammation but also changes in adipocytes and extracellular matrix (ECM) composition might be involved in OA pathogenesis. Fifty-three patients were enrolled. IFP biopsies were obtained, evaluating: (a) lymphocytic infiltration and vascularization; (b) adipocytes area and number; (c) adipo-cytokines and extracellular matrix gene expression levels; (d) IL-6 and VEGF protein production; (e) collagen fibers distribution. OA IFP was more inflamed and vascularized compared to ACL IFP. OA IFP adipocytes were larger and numerically lower (1.3-fold) than ACL IFP adipocytes. An increase of gene expression of typical white adipose tissue genes was observed in OA compared to ACL IFP. Collagen-types distribution was different in the OA IFP group compared to controls, possibly explaining the change of the biomechanical characteristics found in OA IFP. Statistical linear models revealed that the adipocyte area correlated with BMI in the OA group. In conclusion, inflammation and fibrotic changes of OA IFP could represent novel therapeutic targets to counteract OA.
KW - adipocyte
KW - anterior cruciate ligament
KW - inflammation
KW - infrapatellar fat pad
KW - osteoarthritis
U2 - 10.3390/ijms21176016
DO - 10.3390/ijms21176016
M3 - Article
C2 - 32825633
VL - 21
SP - 1
EP - 15
JO - International Journal of Molecular Sciences
JF - International Journal of Molecular Sciences
SN - 1661-6596
IS - 17
ER -