To test the hypothesis that heightened advanced glycation endproducts (AGEs) content in cartilage accelerates the progression of spontaneous osteoarthritis (OA) in the Hartley guinea pig (HGP) model.
Twenty-eight male, 3-month-old HGPs were used. Eight were left untreated as a baseline control group and sacrificed at 3 months of age (n = 4) and 9 months of age (n = 4; age-matched controls). The other 20 HGPs received intra-articular knee injections in the right knee whereas the left knees acted as contra-lateral non-injected controls. Injections consisted of 100 μl phosphate buffered saline (PBS; n = 10) or PBS+2.0 M D-(-)-Ribose (n = 10). Injections were given once weekly for 24 weeks. At the end of the treatment period, the tibiae were fixed with formalin, scanned with microCT for sub-chondral bone mineral density, and then histological slides were prepared, stained with Safranin-O with Fast Green counter stain and scored using the OARSI-HISTOgp scheme. Cartilage pentosidine (established biomarker for AGEs) content, collagen content (% dry mass), glucosaminoglycan GAG-to-collagen ratio (μg/μg), GAG-to-DNA ratio and DNA-to-collagen ratio were measured.
Pentosidine content increased greatly due to PBS + Ribose injection (P < 0.0001) and reached levels found in cartilage from 80-year-old humans. Surprisingly, mean OARSI-HISTOgp scores for both the injected and contra-lateral controls in the PBS + Ribose group were not detectably different, nor were they different from the mean score for the age-matched control group.
AGEs accumulation due to intra-articular ribose-containing injections in the HGP model of spontaneous knee OA did not enhance disease progression.