title: Platelet rich plasma (PRP) induces chondroprotection via increasing autophagy, anti-inflammatory markers, and decreasing apoptosis in human osteoarthritic cartilage.
abstract: OBJECTIVE
  Autophagy constitutes a defense mechanism to overcome aging and apoptosis in osteoarthritic cartilage. Several cytokines and transcription factors are linked to autophagy and play an important role in the degradative cascade in osteoarthritis (OA). Cell therapy such as platelet rich plasma (PRP) has recently emerged as a promising therapeutic tool for many diseases including OA. However, its mechanism of action on improving cartilage repair remains to be determined. The purpose of this study is to investigate the effect of PRP on osteoarthritic chondrocytes and to elucidate the mechanism by which PRP contributes to cartilage regeneration.
  
  
  METHODS
  Osteoarthritic chondrocytes were co-cultured with an increasing concentration of PRP obtained from healthy donors. The effect of PRP on the proliferation of chondrocytes was performed using cell counting and WST8 proliferation assays. Autophagy, apoptosis and intracellular level of IL-4, IL-10, and IL-13 were determined using flow cytometry analyses. Autophagy markers BECLIN and LC3II were also determined using quantitative polymerase chain reaction (qPCR). qPCR and ELISA were used to measure the expression of ADAMDTS-5, MMP3, MMP13, TIMP-1-2-3, aggregan, Collagen type 2, TGF-β, Cox-2, Il-6, FOXO1, FOXO3, and HIF-1 in tissues and co-cultured media.
  
  
  RESULTS
  PRP increased significantly the proliferation of chondrocytes, decreased apoptosis and increased autophagy and its markers along with its regulators FOXO1, FOXO3 and HIF-1 in osteoarthritic chondrocytes. Furthermore, PRP caused a dose-dependent significant decrease in MMP3, MMP13, and ADAMTS-5, IL-6 and COX-2 while increasing TGF-β, aggregan, and collagen type 2, TIMPs and intracellular IL-4, IL-10, IL-13.
  
  
  CONCLUSIONS
  These results suggest that PRP could be a potential therapeutic tool for the treatment of OA.
authors.affiliation: Regenerative medicine and inflammation Laboratory, Faculty of Medicine, Saint-Joseph University, Beirut, Lebanon. Electronic address: Moussa-mayssam@hotmail.com.
authors.forename: Mayssam
authors.initials: M
authors.lastname: Moussa
authors.affiliation: Research Centre in Osteoarthritis, Research Centre in Monteral University, Canada. Electronic address: daniel.lajeunesse@umontreal.ca.
authors.forename: Daniel
authors.initials: D
authors.lastname: Lajeunesse
authors.affiliation: Cancer and metabolism Laboratory, Faculty of Medicine, Saint-Joseph University, Beirut, Lebanon. Electronic address: George2266@gmail.com.
authors.forename: George
authors.initials: G
authors.lastname: Hilal
authors.affiliation: Regenerative medicine and inflammation Laboratory, Faculty of Medicine, Saint-Joseph University, Beirut, Lebanon. Electronic address: oulaatat@hotmail.com.
authors.forename: Oula
authors.initials: O
authors.lastname: El Atat
authors.affiliation: Hotel Dieu de France, Faculty of Medicine, Saint-Joseph University, Beirut, Lebanon. Electronic address: Gaby.haykal@hdf.usj.edu.lb.
authors.forename: Gaby
authors.initials: G
authors.lastname: Haykal
authors.affiliation: Regenerative medicine and inflammation Laboratory, Faculty of Medicine, Saint-Joseph University, Beirut, Lebanon. Electronic address: rim.basbous@gmail.com.
authors.forename: Rim
authors.initials: R
authors.lastname: Serhal
authors.affiliation: Carantina Hospital, Beirut, Lebanon. Electronic address: Mava.o@hotmail.com.
authors.forename: Antonio
authors.initials: A
authors.lastname: Chalhoub
authors.affiliation: Regenerative medicine and inflammation Laboratory, Faculty of Medicine, Saint-Joseph University, Beirut, Lebanon. Electronic address: charbelk3@hotmail.com.
authors.forename: Charbel
authors.initials: C
authors.lastname: Khalil
authors.affiliation: Regenerative medicine and inflammation Laboratory, Faculty of Medicine, Saint-Joseph University, Beirut, Lebanon. Electronic address: Nada.aladdin@gmail.com.
authors.forename: Nada
authors.initials: N
authors.lastname: Alaaeddine
mesh_terms: D000328:Adult; D000893:Anti-Inflammatory Agents / Q000378:metabolism*; D017209:Apoptosis; D001343:Autophagy; D015153:Blotting, Western; D002358:Cartilage, Articular / Q000166:cytology* / Q000378:metabolism; D016022:Case-Control Studies; D049109:Cell Proliferation; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology* / Q000378:metabolism; D005260:Female; D006801:Humans; D016753:Interleukin-10 / Q000235:genetics / Q000378:metabolism; D018793:Interleukin-13 / Q000235:genetics / Q000378:metabolism; D015847:Interleukin-4 / Q000235:genetics / Q000378:metabolism; D008297:Male; D053509:Matrix Metalloproteinase 13 / Q000235:genetics / Q000378:metabolism; D019278:Matrix Metalloproteinase 3 / Q000235:genetics / Q000378:metabolism; D008875:Middle Aged; D010003:Osteoarthritis / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D053657:Platelet-Rich Plasma / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000235:genetics / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000235:genetics / Q000378:metabolism; D055815:Young Adult
chemical_list: D000893:Anti-Inflammatory Agents; C508609:IL10 protein, human; D018793:Interleukin-13; D012333:RNA, Messenger; C560822:TIMP1 protein, human; D019715:Tissue Inhibitor of Metalloproteinase-1; D016212:Transforming Growth Factor beta; D016753:Interleukin-10; D015847:Interleukin-4; C507079:MMP13 protein, human; D053509:Matrix Metalloproteinase 13; C511768:MMP3 protein, human; D019278:Matrix Metalloproteinase 3
keywords: Anti-inflammatory cytokines; Apoptosis; Autophagy; Osteoarthritis; Platelet rich plasma