Oxygen-Loaded Nanodroplets Effectively Abrogate Hypoxia Dysregulating Effects on Secretion of MMP-9 and TIMP-1 by Human Monocytes

Figure 3

Hypoxia and OLN effects on MMP-9 secretion by human monocytes. Human adherent monocytes (10⁶ cells/2 mL Panserin 601 medium) were left untreated or treated with 200 μL OLNs, OFNs, or OSS for 24 h in normoxia (20% O₂; panels (a), (c), and (d): black columns; panel (b): odd lanes) or hypoxia (1% O₂; panels (a), (c), and (d): white columns; panel (b): even lanes). After collection of cell supernatants, MMP-9 protein levels were quantified by ELISA (panel (a)), whereas MMP-9 latent/active forms were analyzed by gelatin zymography (panel (b)) and subsequent densitometry (panels (c)-(d)). For gelatin zymography, recombinant human MMP-9 (83 kDa) was employed as a standard marker (st). Results are shown as means + SEM (panels (a), (c)-(d)) or as a representative gel (panel (b)) from three independent experiments. ELISA and densitometric data were also evaluated for significance by ANOVA: versus normoxic control cells: (panel (a)), (panel (c)), and (panel (d)); versus hypoxic control cells: (panel (b)), (panel (c)), and (panel (d)).

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