Xiaoli Zeng1, Xiaoju Liu2, Hairong Bao1, Yi Zhang1, Xiaohu Wang1, Kai Shi1, Qi Pang1. 1. Department of Gerontal Respiratory Medicine, the First Hospital of Lanzhou University, Lanzhou 730000, China. 2. Department of Gerontal Respiratory Medicine, the First Hospital of Lanzhou University, Lanzhou 730000, China. Email: liuxiaoju835@126.com.
Abstract
OBJECTIVE: To explore the effects of sulforaphane on Toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88) pathway and its downstream inflammatory cytokines in patients with chronic obstructive pulmonary disease (COPD). METHODS: From Jan. 2012 to Mar. 2013, thirty-two stable COPD patients and thirty healthy donors (non-COPD group) from the First Hospital of Lanzhou University were recruited. The peripheral blood monocytes were isolated and induced to macrophages (monocyte-derived macrophages, MDMs). The MDMs of COPD patients were divided into a blank control group, a LPS group, a sulforaphane group, a sulforaphane and LPS group (combined group), while the MDMs from the non-COPD group received no drug intervention. The number of cells in each group was 3×10(6). The mRNA and protein expression of TLR4 and MyD88 were measured with real-time PCR and Western blot. The TNF-α and IL-6 levels in the culture supernatant were measured with ELISA. Oneway ANOVA and LSD-t test were used for statistical analysis. RESULTS: The levels of mRNA and protein of TLR4 and MyD88 and the contents of TNF-α and IL-6 in the culture supernatant were higher in the blank control group [3.7 ± 0.5, 1.9 ± 0.4, 0.45 ± 0.18, 1.11 ± 0.65, (31 ± 4) and (43 ± 5) µg/L] than those in the non-COPD group [1.00, 1.00, 0.26 ± 0.14, 0.58 ± 0.40, (19 ± 2) and (29 ± 4) µg/L] (t = 2.19-12.11, P < 0.05 or P < 0.01). After LPS treatment (LPS group), the above parameters [5.5 ± 1.1, 3.4 ± 1.6, 0.65 ± 0.20, 1.66 ± 0.64, (47 ± 4) and (54 ± 5) µg/L] were increased as compared to those in the blank control group (t = 2.39-11.9, P < 0.05 or P < 0.01), but after sulforaphane treatment(Sulforaphane group), these parameters [2.2 ± 0.4, 1.0 ± 0.6, 0.25 ± 0.09, 0.62 ± 0.34, (20 ± 3) and (27 ± 4) µg/L] were decreased as compared to those in the blank control group (t = 2.13-8.46, P < 0.05 or P < 0.01). Similarly, these parameters in the combined group [3.2 ± 0.5, 1.5 ± 0.8, 0.33 ± 0.11, 0.77 ± 0.25, (31 ± 3) and (33 ± 4) µg/L] were also remarkably decreased as compared to those in the LPS group (t = 3.87-12.24, all P < 0.01). CONCLUSIONS: The TLR4/MyD88 pathway was activated and its downstream inflammatory cytokines were increased in macrophages from COPD patients. Sulforaphane could inhibit the TLR4/MyD88 pathway and reduce the releasing of downstream inflammatory cytokines, suggesting that sulforaphane may have an anti-inflammatory effect in COPD.
OBJECTIVE: To explore the effects of sulforaphane on Toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88) pathway and its downstream inflammatory cytokines in patients with chronic obstructive pulmonary disease (COPD). METHODS: From Jan. 2012 to Mar. 2013, thirty-two stable COPDpatients and thirty healthy donors (non-COPD group) from the First Hospital of Lanzhou University were recruited. The peripheral blood monocytes were isolated and induced to macrophages (monocyte-derived macrophages, MDMs). The MDMs of COPDpatients were divided into a blank control group, a LPS group, a sulforaphane group, a sulforaphane and LPS group (combined group), while the MDMs from the non-COPD group received no drug intervention. The number of cells in each group was 3×10(6). The mRNA and protein expression of TLR4 and MyD88 were measured with real-time PCR and Western blot. The TNF-α and IL-6 levels in the culture supernatant were measured with ELISA. Oneway ANOVA and LSD-t test were used for statistical analysis. RESULTS: The levels of mRNA and protein of TLR4 and MyD88 and the contents of TNF-α and IL-6 in the culture supernatant were higher in the blank control group [3.7 ± 0.5, 1.9 ± 0.4, 0.45 ± 0.18, 1.11 ± 0.65, (31 ± 4) and (43 ± 5) µg/L] than those in the non-COPD group [1.00, 1.00, 0.26 ± 0.14, 0.58 ± 0.40, (19 ± 2) and (29 ± 4) µg/L] (t = 2.19-12.11, P < 0.05 or P < 0.01). After LPS treatment (LPS group), the above parameters [5.5 ± 1.1, 3.4 ± 1.6, 0.65 ± 0.20, 1.66 ± 0.64, (47 ± 4) and (54 ± 5) µg/L] were increased as compared to those in the blank control group (t = 2.39-11.9, P < 0.05 or P < 0.01), but after sulforaphane treatment(Sulforaphane group), these parameters [2.2 ± 0.4, 1.0 ± 0.6, 0.25 ± 0.09, 0.62 ± 0.34, (20 ± 3) and (27 ± 4) µg/L] were decreased as compared to those in the blank control group (t = 2.13-8.46, P < 0.05 or P < 0.01). Similarly, these parameters in the combined group [3.2 ± 0.5, 1.5 ± 0.8, 0.33 ± 0.11, 0.77 ± 0.25, (31 ± 3) and (33 ± 4) µg/L] were also remarkably decreased as compared to those in the LPS group (t = 3.87-12.24, all P < 0.01). CONCLUSIONS: The TLR4/MyD88 pathway was activated and its downstream inflammatory cytokines were increased in macrophages from COPDpatients. Sulforaphane could inhibit the TLR4/MyD88 pathway and reduce the releasing of downstream inflammatory cytokines, suggesting that sulforaphane may have an anti-inflammatory effect in COPD.