PSVI-9 In Vitro Effects of Monoglycerides and Zinc Glycinate: Anti-Inflammatory and Epithelial Barrier Function

• Published in: Journal of animal science 2023-11, Vol.101 (Supplement_3), p.414-415
• Main Authors: Park, Sangwoo, Kovanda, Lauren L, Sokale, Adebayo O O, Barri, Adriana, Liu, Yanhong
• Format: Article
• Language: English
• Subjects: Alveoli; Cell culture; Cell viability; Design of experiments; Electrical resistivity; Enzyme-linked immunosorbent assay; Epithelium; Experimental design; IL-1β; Immune response; In vivo methods and tests; Incubation; Inflammation; Inserts; Lipopolysaccharides; Macrophages; Monoglycerides; Plates; Tumor necrosis factor-TNF; Tumor necrosis factor-α; Variance analysis; Zinc
• ISSN: 0021-8812; 1525-3163
• DOI: 10.1093/jas/skad281.491

Abstract The objectives of this study were to investigate the in vitro anti-inflammatory effects of monoglycerides and zinc glycinate with porcine alveolar macrophages (PAMs) and their impacts on epithelial barrier function using the IPEC-J2 cell line. MTT assays were performed for each compound to determine cell viability and appropriate treatment doses. PAMs were isolated from 6 piglets at 7 weeks of age, and then seeded into 24-well plates with 106 cells/mL. After 24 h incubation, cells were treated with each compound or lipopolysaccharide (LPS). The experimental design was 2 × 6 factorial arrangement with 2 doses of LPS (0 or 1 μg/mL) and 6 doses of each compound (monoglycerides: 0, 50, 100, 250, 500, and 1,000 µg/mL; zinc glycinate: 0, 25, 50, 100, 250, and 500 µg/mL). The supernatants were collected after another 24 h incubation to analyze concentration of tumor necrosis factor α (TNF-α) and interleukin-1β (IL-1β) by ELISA. IPEC-J2 cells (5 × 105 cells/mL) were seeded into 12-well plates on transwell cell culture inserts and cultured until confluence, and then were treated with each compound (monoglycerides: 0, 25, 100, 250, 500, and 1,000 µg/mL; zinc glycinate: 0, 2, 5, 12.5, 25, and 50 µg/mL). Transepithelial electrical resistance (TEER) was measured in Ωcm2 using a Millicell ERS-2 voltohmmeter at 0 h (before treatment) and at 24, 48, and 72 h post-treatment. Data were analyzed by ANOVA using PROC MIXED of SAS with a randomized complete block design. LPS challenge increased (P < 0.05) the production of TNF-α and IL-1β from PAMs. In the non-challenge group, supplementing 50 or 100 μg/mL of monoglycerides stimulated (P < 0.05) TNF-α and IL-1β production from PAMs. Treatment with 25 or 100 μg/mL of zinc glycinate also enhanced (P < 0.05) TNF-α production from PAMs. In LPS-treated PAMs, 1,000 μg/mL of monoglycerides increased (P < 0.05) IL-1β production, while zinc glycinate suppressed (P < 0.0001) the secretion of TNF-α and IL-1β at the doses of 100, 250, and 500 μg/mL. IPEC-J2 cells treated with 250 or 1,000 μg/mL of monoglycerides, or 5 μg/mL of zinc glycinate had increased (P < 0.0001) TEER values at 48 and 72 h post-treatment, compared with control. However, cells treated with 50 μg/mL of zinc glycinate reduced (P < 0.0001) TEER values at 24, 48, and 72 h post-treatment compared with other treatments. In conclusion, results of this in vitro study indicate that monoglycerides have a positive effect on the barrier function of epithelium, while zinc