Figures & data
Scheme 1. Synthesis of compounds D1-D17 and E1-E11. Reagents and conditions: (i) C2H3N, K2CO3, 60 °C, 15 h, R1; (ii) C2H3N, DMF, POCl3; (iii) CH3NO2, CH3COONH4, 100 °C; (iv) DMF, NaN3, P-TSOH, 60 °C; (v)DCM, R2, DMF, (CH3CH2)3N, 2 h.
![Scheme 1. Synthesis of compounds D1-D17 and E1-E11. Reagents and conditions: (i) C2H3N, K2CO3, 60 °C, 15 h, R1; (ii) C2H3N, DMF, POCl3; (iii) CH3NO2, CH3COONH4, 100 °C; (iv) DMF, NaN3, P-TSOH, 60 °C; (v)DCM, R2, DMF, (CH3CH2)3N, 2 h.](/cms/asset/d9e82c6d-2ceb-4383-aec6-d87ae9855068/ienz_a_2315227_sch0001_b.jpg)
Figure 3. The cytotoxicity of the pterostilbene derivatives was tested by MTT assay. RAW264.7 cells were pre-incubated with compound (20 μM) for 24 h and then were detected by MTT assay. All data are expressed as mean ± standard deviation.
![Figure 3. The cytotoxicity of the pterostilbene derivatives was tested by MTT assay. RAW264.7 cells were pre-incubated with compound (20 μM) for 24 h and then were detected by MTT assay. All data are expressed as mean ± standard deviation.](/cms/asset/b71e784b-9a66-499f-9092-39e5b837e8ac/ienz_a_2315227_f0003_c.jpg)
Figure 4. Inhibitory effects of the synthetic compounds (D1-D17) on LPS-induced NO production. ***P < 0.001 Compared with LPS treated group. Cel: celecoxib; as a positive control.
![Figure 4. Inhibitory effects of the synthetic compounds (D1-D17) on LPS-induced NO production. ***P < 0.001 Compared with LPS treated group. Cel: celecoxib; as a positive control.](/cms/asset/3909eaee-9f7b-4859-89c5-feb2002e1a21/ienz_a_2315227_f0004_c.jpg)
Table 1. Compounds E1-E13 inhibitory activity against NO release.
Figure 5. Inhibition of inflammatory protein expression by compound E2. RAW264.7 was pre-treatment with compounds (2 µM, 1 µM, 0.5 µM) for 1 h, and then exposed to LPS (500 ng/mL) for 24 h. Bay11-7082 (1 µM) is an NF-κB signalling pathway inhibitor. *** P < 0.001 compared with LPS treated group.
![Figure 5. Inhibition of inflammatory protein expression by compound E2. RAW264.7 was pre-treatment with compounds (2 µM, 1 µM, 0.5 µM) for 1 h, and then exposed to LPS (500 ng/mL) for 24 h. Bay11-7082 (1 µM) is an NF-κB signalling pathway inhibitor. *** P < 0.001 compared with LPS treated group.](/cms/asset/c83710d6-abba-4933-83bd-0dc7beb20cbe/ienz_a_2315227_f0005_b.jpg)
Figure 6. Inhibition of NF-κB inflammatory signalling pathway by compound 8. RAW264.7 was pre-treatment with compound 8 (2 µM, 1 µM, 0.5 µM) for 1 h, and then exposed to LPS (500 ng/mL) for 30 min. Bay11-7082 (1 µM) is an NF-κB signalling pathway inhibitor. *** P < 0.001 compared with LPS treated group.
![Figure 6. Inhibition of NF-κB inflammatory signalling pathway by compound 8. RAW264.7 was pre-treatment with compound 8 (2 µM, 1 µM, 0.5 µM) for 1 h, and then exposed to LPS (500 ng/mL) for 30 min. Bay11-7082 (1 µM) is an NF-κB signalling pathway inhibitor. *** P < 0.001 compared with LPS treated group.](/cms/asset/c3e0a3cb-406c-4d34-96a7-a5ae03fee43f/ienz_a_2315227_f0006_b.jpg)
Figure 7. Inhibition of MAPKs inflammatory signalling pathway by compound E2. RAW264.7 was pre-treatment with compound E2 (2 µM, 1 µM, 0.5 µM) for 1 h, and then exposed to LPS (500 ng/mL) for 30 min. *** P < 0.001 compared with LPS treated group.
![Figure 7. Inhibition of MAPKs inflammatory signalling pathway by compound E2. RAW264.7 was pre-treatment with compound E2 (2 µM, 1 µM, 0.5 µM) for 1 h, and then exposed to LPS (500 ng/mL) for 30 min. *** P < 0.001 compared with LPS treated group.](/cms/asset/94c99355-5069-488c-99f7-479b0f84bfa5/ienz_a_2315227_f0007_b.jpg)
Figure 8. Compound E2 alleviates DSS-induced colitis in mice. (a) Mice show bloody stools (b) Weight change; (c) DAI was calculated; (d, e) Measuring the length of the colon; (f) Histopathological analysis of mouse colon. Data are represented as mean and SEM. Sulfasalazine (SASP) was used as a positive control drug. Compared with the Normal group, ### P < 0.001; Compared with DSS treated group, *** P < 0.001.
![Figure 8. Compound E2 alleviates DSS-induced colitis in mice. (a) Mice show bloody stools (b) Weight change; (c) DAI was calculated; (d, e) Measuring the length of the colon; (f) Histopathological analysis of mouse colon. Data are represented as mean and SEM. Sulfasalazine (SASP) was used as a positive control drug. Compared with the Normal group, ### P < 0.001; Compared with DSS treated group, *** P < 0.001.](/cms/asset/b8e3c8db-857c-4fc1-a9ca-829eba0be9f8/ienz_a_2315227_f0008_c.jpg)
Figure 9. Compound E2 inhibits pro-inflammatory factor expression and MPO levels. (a) Detection of MPO activity in colon tissue. (b − d) ELISA determined the cytokine levels of TNF-α, IL-1β, and IL-6. Values are expressed as a mean ± SEM. ### P < 0.001 compared with the Normal group; *** P < 0.001 Compared with DSS treated group.
![Figure 9. Compound E2 inhibits pro-inflammatory factor expression and MPO levels. (a) Detection of MPO activity in colon tissue. (b − d) ELISA determined the cytokine levels of TNF-α, IL-1β, and IL-6. Values are expressed as a mean ± SEM. ### P < 0.001 compared with the Normal group; *** P < 0.001 Compared with DSS treated group.](/cms/asset/2e62e24f-c093-4e0b-9c16-411f6ab7cad1/ienz_a_2315227_f0009_c.jpg)
Figure 10. Compound E2 treatment downregulated the Inflammatory proteins and signalling pathway in acute DSS-induced colitis. (A-F) TNF-α, IL-1β, IL-6, iNOS, COX-2 and TLR4 mRNA levels in colon tissues. (G-J) Representative Western blot images of colonic COX-2, p-NF-κB, p-Stat3, and β-actin proteins. Compared with Normal group, ### P < 0.001; Compared with DSS treated group, *** P < 0.001.
![Figure 10. Compound E2 treatment downregulated the Inflammatory proteins and signalling pathway in acute DSS-induced colitis. (A-F) TNF-α, IL-1β, IL-6, iNOS, COX-2 and TLR4 mRNA levels in colon tissues. (G-J) Representative Western blot images of colonic COX-2, p-NF-κB, p-Stat3, and β-actin proteins. Compared with Normal group, ### P < 0.001; Compared with DSS treated group, *** P < 0.001.](/cms/asset/8740b36f-8a4c-46e3-99d5-a3957f91636e/ienz_a_2315227_f0010_c.jpg)