Targeting multiple disease hallmarks using a synergistic disease-modifying drug combination ameliorates osteoarthritis via inhibition of senescence and inflammation.

AIMS: Osteoarthritis (OA), is a debilitating disease characterized by progressive cartilage degradation, synovial inflammation, and chondrocyte senescence. Various treatment agents independently targeting these hallmarks have been investigated. However, due to the complex multifaceted nature of OA, no disease-modifying osteoarthritis drugs are clinically available. In an attempt to overcome this, we developed a combinatorial approach and demonstrated the efficacy of TsC [Tissue inhibitor of metalloproteinase-3 (TIMP3) + sulfated carboxymethylcellulose (sCMC)] and piperlongumine (PL) combination for the amelioration of OA in a goat ex vivo OA model. MAIN METHODS: The efficacy of the drug combination was evaluated using the goat ex vivo OA explant model and results were validated in clinically relevant human OA cartilage explants. The chondroprotective effects were evaluated in terms of reduced inflammation and cartilage matrix loss, reduction in chondrosenescence, and reduced oxidative stress. KEY FINDINGS: A combination of TsC and PL (TsC-PL) significantly reduced inflammation, cartilage matrix loss, chondrosenescence, and oxidative stress in the goat ex vivo OA model and showed chondroprotective effects. Further, similar chondroprotective effects were observed in human OA cartilage. Additionally, the coefficient of drug interaction analysis indicated that the combination of TsC and PL had a synergistic effect in reducing matrix degrading proteases and inflammation (goat ex vivo OA model) and Reactive oxygen species (ROS) production (human OA cartilage). SIGNIFICANCE: Combinatorial treatment with TsC and PL demonstrated potential disease-modifying effects for the treatment of osteoarthritis via inhibition of inflammation and senescence and supports the usage of treatment strategies targeting multiple pathological factors of OA simultaneously.

Sulfated carboxymethylcellulose mediated enhancement of Timp3 efficacy synergistically attenuates osteoarthritis through inhibition of NFκB and JNK.

Osteoarthritis (OA) is a prevalent degenerative joint condition with no effective disease modifying treatments. In this study, we aimed to address multiple OA hallmarks using a combination of pro-chondrogenic sulfated carboxymethylcellulose (sCMC) and anti-catabolic tissue inhibitor of metalloproteases 3 (Timp3) in relevant disease systems. Firstly, we chemically sulfated carboxymethylcellulose to impart a negative charge and improve the stability of cationic Timp3. The modified sCMC exhibited a molecular weight of 10 kDa and a degree of sulfation of ∼10 %. We further demonstrated that sulfation of CMC confers pro-chondrogenic characteristics. Subsequently, we demonstrated that the combination of sCMC and Timp3 effectively reduced key OA hallmarks, such as matrix degradation, inflammation, and protease expression, in a goat ex vivo OA model compared to individual treatments. We further demonstrated that the anti-OA effect of sCMC and Timp3 is mediated through the suppression of NFκB and JNK activation. To validate the clinical potential and mechanism of action, we conducted experiments on human OA explants. The combination treatment synergistically reduced the expression of MMP13 and NFκB in human OA explants. Overall, sCMC-mediated enhancement of Timp3 efficacy synergistically reduced OA-like traits and demonstrates the potential for OA amelioration.

Measurement of Posterior Tibial Slope in Healthy Indian Population: A CT-Based Study.

Background: Recreation of near normal posterior tibial slope is required for proper knee biomechanics after unicondylar as well as total knee arthroplasties. It is also required for proper functioning of anterior cruciate ligament after high tibial osteotomies. Researchers have found differences in values of posterior tibial slopes in individuals of different ethnicities. So far there is no study measuring the posterior slopes of medial and lateral tibial plateau separately in knees of healthy Indian population via three dimensional imaging modalities like computed tomography. Aim: The aim of our study is to find out the slopes of medial and lateral tibial plateau separately through computed tomography (CT) scans. Materials and Methods: CT-based measurements of posterior tibial slopes were done in 62 healthy knees. There were 55 males and 7 females. Results: Age groups were in the range of 17-45 years. Mean values of Posterior tibial slope of medial and lateral tibial plateau for combined sample were 8.60° ± 3.51° and 7.94° ± 3.91°. Mean values of medial and lateral tibial plateau for males were 8.33° ± 3.51° and 7.71° ± 4.07° respectively; while for females were 10.69° ± 2.86° and 9.77° ± 1.32°, respectively.In our study, there was a large range of slopes, extending from + 0.6° to 15.6° for medial tibial slope, from 0° to 15° for lateral tibial slope. Conclusion: The minimum values of Medial tibial plateau slope are very low as compared to the previous study done in Asian population. Further CT based studies are required to measure values of posterior tibial slope for larger sample from Indian population. The implant design suitable and their implantation guidelines for western population may not be appropriate for Indian population.

Decalcified allograft in repair of lytic lesions of bone: A study to evolve bone bank in developing countries.

BACKGROUND: The quest for ideal bone graft substitutes still haunts orthopedic researchers. The impetus for this search of newer bone substitutes is provided by mismatch between the demand and supply of autogenous bone grafts. Bone banking facilities such as deep frozen and freeze-dried allografts are not so widely available in most of the developing countries. To overcome the problem, we have used partially decalcified, ethanol preserved, and domestic refrigerator stored allografts which are economical and needs simple technology for procurement, preparation, and preservation. The aim of the study was to assess the radiological and functional outcome of the partially decalcified allograft (by weak hydrochloric acid) in patients of benign lytic lesions of bone. Through this study, we have also tried to evolve, establish, and disseminate the concept of the bone bank. MATERIALS AND METHODS: 42 cases of lytic lesions of bone who were treated by decalcified (by weak hydrochloric acid), ethanol preserved, allografts were included in this prospective study. The allograft was obtained from freshly amputated limbs or excised femoral heads during hip arthroplasties under strict aseptic conditions. The causes of lytic lesions were unicameral bone cyst (n = 3), aneurysmal bone cyst (n = 3), giant cell tumor (n = 9), fibrous dysplasia (n = 12), chondromyxoid fibroma, chondroma, nonossifying fibroma (n = 1 each), tubercular osteomyelitis (n = 7), and chronic pyogenic osteomyelitis (n = 5). The cavity of the lesion was thoroughly curetted and compactly filled with matchstick sized allografts. RESULTS: Quantitative assessment based on the criteria of Sethi et al. (1993) was done. There was complete assimilation in 27 cases, partial healing in 12 cases, and failure in 3 cases. Functional assessment was also done according to which there were 29 excellent results, 6 good, and 7 cases of failure (infection, recurrence, and nonunion of pathological fracture). We observed that after biological incorporation, the graft participates in bone physiology and morphology. We did not observe any adverse host graft antigenic reaction. CONCLUSIONS: We conclude that decalcified allograft is suitable alloimplant for use in benign lesions of bone, is easy to prepare and store, and is thus well suited for use in developing countries.

Hydroxyapatite crystals as a bone graft substitute in benign lytic lesions of bone.

BACKGROUND: Bone grafts are required to fill a cavity created after curettage of benign lytic lesions of the bone. To avoid the problems associated at donor site with autologous bone graft, we require allograft or bone graft substitutes. We evaluated the healing of lytic lesions after hydroxyapatite (HA) grafting by serial radiographs. MATERIALS AND METHODS: Forty cases of benign lytic lesions of bone were managed by simple curettage and grafting using HA blocks. Commercially available HA of bovine origin (Surgiwear Ltd., Shahjahanpur, India) was used for this purpose. Mean duration of followup was 34.8 months (range 12-84 months). Mean patient age was 19.05 years (range 3-55 years). Radiological staging of graft incorporation was done as per criteria of Irwin et al. 2001. RESULTS: In our series, two cases were in stage I. A total of 11 cases were in stage II and 27 were in stage III. Graft incorporation was radiologically complete by 15 months. Clinical recovery was observed before radiological healing. The average time taken to return to preoperative function was 3 months. Recurrence was observed in giant cell tumor (n = 3) and chondromyxoid fibroma (n = 1). There was no incidence of graft rejection, collapse, growth plate disturbances or antigenic response. CONCLUSIONS: We conclude that calcium HA is biologically acceptable bone graft substitute in the management of benign lytic lesions of bone.