Effects of doxycycline on mesenchymal stem cell chondrogenesis and cartilage repair

Abstract

Objective Strategies to improve cartilage repair tissue quality after bone marrow cell-based procedures may reduce later development of osteoarthritis. Doxycycline is inexpensive, well-tolerated, and has been shown to reduce matrix-metalloproteinases (MMP) and osteoarthritis progression. This study tests the hypotheses that doxycycline reduces MMP, enhances chondrogenesis of human bone marrow-derived mesenchymal stem cells (hMSC), and improves in vivo cartilage repair. Design Ninety hMSC pellets were cultured in chondrogenic media with either 0-, 1- or 2-μg/mL doxycycline. Pellets were evaluated with stereomicroscopy, proteoglycan assay, qRT-PCR, and histology. Osteochondral defects (OCD) were created in the trochlear grooves of 24-Sprague-Dawley rats treated with/without oral doxycycline. Rats were sacrificed at 12-weeks and repair tissues were examined grossly and histologically. Results hMSC pellets with 1-μg/mL (p=0.014) and 2-μg/mL (p=0.002) doxycycline had larger areas than pellets without doxycycline. hMSC pellets with 2-μg/mL doxycycline showed reduced mmp-13 mRNA (p=0.010) and protein at 21-days. Proteoglycan, DNA contents, and mRNA expressions of chondrogenic genes were similar (p>0.05). For the in vivo study, while the histological scores were similar between the two groups (p=0.116), the gross scores of the OCD repair tissues in doxycycline-treated rats were higher at 12-weeks (p=0.017), reflective of improved repair quality. The doxycycline-treated repairs also showed lower MMP-13 protein (p=0.029). Conclusions This study shows that doxycycline improves hMSC chondrogenesis and decreases MMP-13 in pellet cultures and within rat OCDs. Doxycycline exerted no negative effect on multiple measures of chondrogenesis and cartilage repair. These data support potential use of doxycycline to improve cartilage repair to delay the onset of osteoarthritis.

Tissue-engineered cartilage with inducible and tunable immunomodulatory properties

“…Recent advances in dox-inducible gene expression systems allow for fine-tuned control of transgene expression with low promoter leakiness and sensitivity to lower levels of dox [30]. Dox does not negatively affect MSC chondrogenesis [75] and has also been clinically tested as a disease-modifying drug for OA [76]. Rather than controlling timing of transduction with release of vectors from encapsulation within a biomaterial, in this study IL-1Ra secretion following transduction is exogenously regulated by dox.…”

Persistence, Localization, and External Control of Transgene Expression After Single Injection of Adeno-Associated Virus into Injured Joints

“…In addition, the use of doxycycline as the transgene inducer molecule may have added beneficial effect for cartilage protection. Doxycycline inhibits collagen-degrading enzymes such as matrix metalloproteinases (MMPs), and has shown beneficial effects in both OCD and ACLT injury models by preventing MMP upregulation (Yu et al, 1992;Lee et al, 2013).…”

“…Twenty-four rats underwent unilateral OCD surgeries, while the other 24 rats underwent ACLT surgeries as previously described (Williams et al, 1982;Lee et al, 2013). Briefly, all the procedures were carried out while the animals were anesthetized with inhalation of isoflurane (Phoenix Pharmaceuticals): 2-5% for induction and 0.25-4.0% for maintenance.…”

Direct conversion of human fibroblasts into therapeutically active vascular wall-typical mesenchymal stem cells

“…These doxycycline effects were mediated by a direct modulation of different cellular pathways, e.g. activation of PI3 K/AKT intracellular signaling [113] or inhibition of matrix metalloproteinases (MMP) [115]. However, to achieve cell fate switching efficiently, lineage regulating genes must be uniformly induced [65].…”