Osteoarthritis and cartilage · 2026
Metal cations Mg2+ and Ca2+ are major mediators of synovial fluid protection against fatigue failure of devitalized immature bovine cartilage under cyclical compression.
СтатьяНазвание и аннотация: Перевод пока не подготовлен
Обработка статьи · этапы, ошибки и управление
Загрузка состояния…
Ошибки и ограничения
История · было → стало
Состояние обновляется каждые 5 секунд, пока блок открыт. Процент показывается только там, где известен объём работы. Пауза останавливает продолжение этапа; текущий запрос к источнику может завершиться.
Zhang H, Weiss J H, Li M, Deiters S, Baxter M, Hung C T, Ateshian G A
Аннотация
OBJECTIVE: The constituent(s) responsible for synovial fluid (SF)'s protection against fatigue failure of devitalized immature bovine cartilage under cyclical compressive loading remain unknown. Based on previous studies and preliminary screening experiments, we hypothesized that Mg2+ and Ca2+ are major mediators of SF protection, whereas major protein and lipid constituents of mature bovine SF-bovine serum albumin (BSA), γ-globulin, and surface-active phospholipids (SAPL)-are not. We further hypothesized that no other major SF constituents are responsible.
DESIGN: Immature bovine femoral condyle cartilage plugs were tested in three sequential in vitro experiments. Experiment 1 (E1) compared baths containing BSA, γ-globulin, SAPL, BSA + γ-globulin + SAPL, and SF (n = 10 per group). E2 compared baths containing Mg2+, Ca2+, Mg2+ + Ca2+, neither Mg2+ nor Ca2+, and SF (n = 10 per group). E3 compared EDTA-chelated SF and unmodified SF (n = 8 per group). Paired samples were subjected to cyclical compressive loading (2 Hz) under a 54.4 ± 1.3 N load (~4-4.5MPa) for up to 36 K cycles. Fatigue damage was assessed by surface roughness, visual inspection, polarized light microscopy (PLM), and histology.
RESULTS: In E1, 10/10 BSA, 10/10 γ-globulin, 9/10 SAPL, and 10/10 BSA + γ-globulin + SAPL samples were damaged, compared with 0/10 SF samples. In E2, 10/10 samples lacking both Mg2+ and Ca2+ were damaged, compared with 0/10 Mg2+ + Ca2+ and 1/10 SF samples; partial protection was observed with Mg2+ (3/10 damaged) and Ca2+ (4/10 damaged). In E3, 7/8 EDTA-chelated SF samples were damaged, compared with 0/8 SF samples. Surface roughness (Rq) increased significantly after testing in all groups exhibiting extensive qualitative fatigue damage (all p < 0.001), whereas no statistically significant changes were detected in the SF, Mg2+, Ca2+, and Mg2+ + Ca2+ groups (all p ≥ 0.364).
CONCLUSIONS: Mg2+ and Ca2+ are the major mediators of SF protection against cartilage fatigue failure under cyclical compressive loading (E2). Chelation of metal cations abolished this protection (E3), whereas the major protein and lipid constituents of SF (BSA, γ-globulin, and SAPL), individually or in combination (E1), as well as all other SF constituents (E3), failed to reproduce it.
DESIGN: Immature bovine femoral condyle cartilage plugs were tested in three sequential in vitro experiments. Experiment 1 (E1) compared baths containing BSA, γ-globulin, SAPL, BSA + γ-globulin + SAPL, and SF (n = 10 per group). E2 compared baths containing Mg2+, Ca2+, Mg2+ + Ca2+, neither Mg2+ nor Ca2+, and SF (n = 10 per group). E3 compared EDTA-chelated SF and unmodified SF (n = 8 per group). Paired samples were subjected to cyclical compressive loading (2 Hz) under a 54.4 ± 1.3 N load (~4-4.5MPa) for up to 36 K cycles. Fatigue damage was assessed by surface roughness, visual inspection, polarized light microscopy (PLM), and histology.
RESULTS: In E1, 10/10 BSA, 10/10 γ-globulin, 9/10 SAPL, and 10/10 BSA + γ-globulin + SAPL samples were damaged, compared with 0/10 SF samples. In E2, 10/10 samples lacking both Mg2+ and Ca2+ were damaged, compared with 0/10 Mg2+ + Ca2+ and 1/10 SF samples; partial protection was observed with Mg2+ (3/10 damaged) and Ca2+ (4/10 damaged). In E3, 7/8 EDTA-chelated SF samples were damaged, compared with 0/8 SF samples. Surface roughness (Rq) increased significantly after testing in all groups exhibiting extensive qualitative fatigue damage (all p < 0.001), whereas no statistically significant changes were detected in the SF, Mg2+, Ca2+, and Mg2+ + Ca2+ groups (all p ≥ 0.364).
CONCLUSIONS: Mg2+ and Ca2+ are the major mediators of SF protection against cartilage fatigue failure under cyclical compressive loading (E2). Chelation of metal cations abolished this protection (E3), whereas the major protein and lipid constituents of SF (BSA, γ-globulin, and SAPL), individually or in combination (E1), as well as all other SF constituents (E3), failed to reproduce it.