Figure 4.

RSG decreases IL-1β/FAC-induced intracellular iron content and oxidative stress levels

(A) Intracellular Fe²⁺ detected by FerroOrange and visualized using fluorescence microscopy (scale bar = 200 μm).

(B) Quantification of FerroOrange fluorescence intensity (n = 3 per group).

(C) Mitochondrial Fe²⁺ concentration determined via Mito-FerroGreen and visualized using fluorescence microscopy (scale bar = 200 μm).

(D) Quantification of Mito-FerroGreen fluorescence intensity (n = 3 per group).

(E) Intracellular Fe²⁺ detected by flow cytometry using FerroOrange.

(F) Quantitative analysis of flow cytometric measurements (n = 3 per group).

(G) Intramitochondrial Fe²⁺ concentration detected by flow cytometry using Mito-FerroGreen.

(H) Quantitative analysis of flow cytometry (n = 3 per group).

(I) Levels of Fe²⁺ in chondrocytes detected using a Fe²⁺ content assay kit (n = 4 per group).

(J) Mitochondrial oxidative stress levels evaluated by mtSOX Deep Red and visualized using fluorescence microscopy (scale bar = 200 μm).

(K) Quantification of mtSOX Deep Red fluorescence intensity (n = 3 per group).

(L) Intracellular ROS detected by DCFH-DA and visualized using fluorescence microscopy (scale bar = 400 μm).

(M) DCFH-DA fluorescence intensity quantification (n = 3 per group).

(N) Fluorescence intensity of DCFH-DA detected using flow cytometry.

(O) Quantitative analysis of flow cytometry (n = 3 per group).

(P and Q) Levels of glutamate (n = 4 per group) and glutamine (n = 6 per group).

(R) Intracellular GSH content (n = 4 per group).

(S) Intracellular GSSG content (n = 4 per group).

(T) Intracellular GSH/GSSG (glutathione redox ratio) (n = 4 per group).

(U) Intracellular SOD activity measurement (n = 4 per group). Two-tailed p values were calculated, and statistical significance was defined as p < 0.05, denoted as 'ns' for no statistical difference, and indicated as ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001. All experiments and images shown are representative.