Effects of Different Doses of Glucosamine Hydrochloride on Cartilage Tissue and Levels of Joint Injury Markers in Knee Osteoarthritis

Abstract

This study analysed the effects of different doses of glucosamine hydrochloride (GS-HCl) on cartilage tissue and the levels of joint injury markers in knee osteoarthritis (KOA). The Sham group, KOA group, low-dose GS-HCl group and high-dose GS-HCl group were established, with six mice in each group. The levels of joint injury markers (COMP, CS846 and CTX-II), inflammatory cytokines (IL-6, TNF-α and iNOS), oxidative stress indicators (MDA and SOD) and matrix remodelling proteins (MMP-3 and TIMP-1) were analysed. The degeneration of knee femoral condyles, histopathological changes and tissue apoptosis rate of the articular cartilage was also assessed. Mice in the KOA group displayed elevated COMP, CS846, CTX-II, IL-6, TNF-α, iNOS and MDA contents, reduced SOD activity, an irregular articular cartilage surface, a serious cartilage defect, a disordered articular cartilage surface in the defect, disappeared cartilage cells, obvious synovial cell proliferation and visible inflammatory cell infiltration. In the tissue, apoptosis rate and MMP-3 and TIMP-1 protein expression increased. Different doses of GS-HCl treatment could reduce COMP, CS846, CTX-II, IL-6, TNF-α, iNOS and MDA contents, apoptosis rate and MMP-3 and TIMP-1 protein expression, increase SOD activity and improve histopathological conditions in KOA mice. The improvement effects in each indicator in the high dose-GS-HCl group were more significant than those in the low dose-GS-HCl group. The intragastric administration of the GS-HCl group partially prevents the degeneration of articular cartilage in KOA mice. The mechanism may be to reduce inflammatory factors and oxidative stress indicator expression and matrix degradation, thereby delaying osteoarthritis progression.

Keywords: cartilage tissue; different doses; glucosamine hydrochloride; joint injury; knee osteoarthritis; markers.

FIGURE 1

GS‐HCl treatment ameliorates joint injury in KOA mice. KOA mouse models were established by the ACLT method. (A–C) At 3 and 7 days as well as 2, 4 and 8 weeks after modelling, blood specimens were collected from each group of mice. Serum CTX‐II, CS846 and COMP levels were measured by ELISA. n = 6; Data are presented as mean ± standard deviation, and two‐way ANOVA was used for statistical analysis, followed by Tukey's post hoc test; *p < 0.05 vs. the Sham group, # p < 0.05 vs. the low‐dose GS‐HCl group and ^ p < 0.05 vs. the high‐dose GS‐HCl group.

FIGURE 2

GS‐HCl reduces cartilage histopathological damage in KOA mice. (A) The histopathology of articular cartilage in KOA mice was observed by HE staining, with black arrows pointing to chondrocytes; (B) Safranin O staining was used to observe the proteoglycan content in the articular cartilage tissue of mice; (C) The degeneration of articular cartilage in knee femoral condyles of KOA mice was assessed by Mankin scores. n = 6; Data are presented as mean ± standard deviation, and one‐way ANOVA was used for statistical analysis, followed by Tukey's post hoc test; *p < 0.05.

FIGURE 3

GS‐HCl diminishes apoptosis in cartilage tissue of KOA mice. TUNEL staining was utilised to test apoptosis in the tissues of KOA mice, n = 6; Data are presented as mean ± standard deviation, and one‐way ANOVA was used for statistical analysis, followed by Tukey's post hoc test; *p < 0.05.

FIGURE 4

GS‐HCl treatment ameliorates inflammation responses in KOA mice. (A–C) The levels of IL‐6, TNF‐α and iNOS in the serum of KOA mice were tested by ELISA; n = 6; Data are presented as mean ± standard deviation, and one‐way ANOVA was used for statistical analysis, followed by Tukey's post hoc test; *p < 0.05.

FIGURE 5

GS‐HCl treatment improves oxidative stress response in KOA mice. (A, B) MDA contents and SOD activity in the serum of KOA mice were assessed by kits; n = 6; Data are presented as mean ± standard deviation, and one‐way ANOVA was used for statistical analysis, followed by Tukey's post hoc test; *p < 0.05.

FIGURE 6

GS‐HCl treatment improves matrix degradation in KOA mice. MMP‐3 and TIMP‐1 protein expression in cartilage tissues of KOA mice after low‐dose GS‐HCl and high‐dose GS‐HCl treatment was tested by western blot assay. n = 6; Data are presented as mean ± standard deviation, and one‐way ANOVA was used for statistical analysis, followed by Tukey's post hoc test; *p < 0.05.