Obesity alters the collagen organization and mechanical properties of murine cartilage

Abstract

Osteoarthritis is a debilitating disease characterized by cartilage degradation and altered cartilage mechanical properties. Furthermore, it is well established that obesity is a primary risk factor for osteoarthritis. The purpose of this study was to investigate the influence of obesity on the mechanical properties of murine knee cartilage. Two-month old wild type mice were fed either a normal diet or a high fat diet for 16 weeks. Atomic force microscopy-based nanoindentation was used to quantify the effective indentation modulus of medial femoral condyle cartilage. Osteoarthritis progression was graded using the OARSI system. Additionally, collagen organization was evaluated with picrosirius red staining imaged using polarized light microscopy. Significant differences between diet groups were assessed using t tests with p < 0.05. Following 16 weeks of a high fat diet, no significant differences in OARSI scoring were detected. However, we detected a significant difference in the effective indentation modulus between diet groups. The reduction in cartilage stiffness is likely the result of disrupted collagen organization in the superficial zone, as indicated by altered birefringence on polarized light microscopy. Collectively, these results suggest obesity is associated with changes in knee cartilage mechanical properties, which may be an early indicator of disease progression.

Effect of short-term high fat diet on resistin levels and expression of autophagy-related genes in the cartilage of male rats

“…In another study by Collins et al 31 , a high-fat/high-sucrose (HFS) diet caused OA-like joint degeneration in the shoulders, knees, and hips in a rat model of OA. In a mouse model, it was also discovered that a 16-week high-fat diet introduction was linked to alterations in knee cartilage mechanical characteristics, which are thought to be an early predictor of OA development 32 .…”

Evidence-based non-pharmacological treatment of osteoarthritis

“…Nowadays, osteoarthritis (oa) has become increasingly perceived as a huge global issue and the most common rheumatic disease (1,2). The socioeconomic and health significance of oa in the overall pathology of the population is continuously increasing, mainly due to a significant increase in two risk factors: an increase in the share of the elderly in the overall population and an increase in the number of obese individuals in the overall population, especially in the younger (working-age) age groups (3,4). There is a significantly positive correlation between the incidence of oa and both risk factors, which is why this disease will continue to be in the centre of interest of both public health workers as well as rheumatologists and physiatrists for a long time.…”

“…There is a significantly positive correlation between the incidence of oa and both risk factors, which is why this disease will continue to be in the centre of interest of both public health workers as well as rheumatologists and physiatrists for a long time. The disease (oa) is manifested by morphological, biochemical, molecular, and biomechanical changes of cells and intercellular substance in all tissues that make up the diarthrodial joint (2,4). Therefore, we need to be aware of the fact that oa is a disease which affects the entire joint and periarticular structures, not just the articular cartilage as is most commonly thought.…”

“…so, with this in mind, the professional societies of the Croatian medical association, such as the Croatian society for rheumatology in 2010 (5) and the Croatian society of uVoD osteoartritis (oa) se sve više percipira kao velik globalni problem i najučestalija reumatska bolest današnjice (1,2). sve je veće i socioekonomsko i zdravstveno značenje oa u sveukupnoj patologiji pučanstva, a poglavito zbog znatnog povećanja dvaju rizičnih čimbenika: porasta udjela starijih osoba u sveukupnoj populaciji i porasta broja pretilih osoba u sveukupnoj populaciji, poglavito u mlađim (radno aktivnim) dobnim skupinama (3,4). Pritom postoji znatno pozitivna korelacija između pojavnosti oa i obaju rizičnih čimbenika, zbog čega će ova bolest dugo biti u središtu zanimanja i javnozdravstvenih radnika i reumatologa i fizijatara.…”

“…Pritom postoji znatno pozitivna korelacija između pojavnosti oa i obaju rizičnih čimbenika, zbog čega će ova bolest dugo biti u središtu zanimanja i javnozdravstvenih radnika i reumatologa i fizijatara. Bolest (oa) se manifestira morfološkim, biokemijskim, molekularnim i biomehaničkim promjenama stanica i međustanične tvari u svim tkivima koja čine diartrodijalni zglob (2,4). zato trebamo biti svjesni činjenice da je oa bolest cijeloga zgloba i okolozglobnih struktura, a ne samo zglobne hrskavice kao što se najčešće mislilo.…”