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4-Hydroxyisoleucine relieves inflammation through iRhom2-dependent pathway in co-cultured macrophages and adipocytes with LPS stimulation.

ABSTRACT: Background: 4-Hydroxyisoleucine (4-HIL) is an active ingredient extracted from Trigonella foenum-graecum L., a Chinese traditional herbal medicine, which exerts the efficacy of anti-obesity and anti-diabetes. We previously reported that 4-HIL potentiates anti-inflammatory and anti-insulin resistance effects through down-regulation of TNF-? and TNF-? converting enzyme (TACE) in 3?T3-L1 adipocytes and HepG2 cells. In the present study, we further investigate the effects and mechanisms of 4-HIL on obesity-induced inflammation in RAW264.7 macrophages and 3?T3-L1 adipocytes co-culture system.

Methods: RAW264.7 macrophages and 3?T3-L1 adipocytes were co-cultured to mimic the microenvironment of adipose tissue. siRNA-iRhom2 transfection was performed to knockdown iRhom2 expression in RAW264.2 macrophages. The mRNA and protein expression of iRhom2 and TACE were measured by real-time quantitative PCR (RT-qPCR) and western blotting. The production of tumor necrosis factor-? (TNF-?), monocyte chemotactic protein-1 (MCP-1), IL-6 and IL-10 were evaluated by ELISA. The ratio of M2/M1 was detected by flow cytometry.

Results: 4-HIL significantly repressed the mRNA and protein levels of iRhom2 and TACE in RAW264.7 macrophages after LPS stimulated. Meanwhile, the levels of pro-inflammatory cytokines, including TNF-?, MCP-1, and IL-6, were substantially suppressed by 4-HIL in the co-culture system. Moreover, the level of anti-inflammatory cytokine IL-10 was increased significantly by 4-HIL in the co-culture system after LPS stimulation. Additionally, the ratio of M2/M1 was also increased by 4-HIL in the co-culture system after LPS stimulation. Finally, these effects of 4-HIL were largely enhanced by siRNA-iRhom2 transfection.

Conclusion: Taken together, our results indicated that obesity-induced inflammation was potently relieved by 4-HIL, most likely through the iRhom2-dependent pathway.

SUBMITTER: Zhou C

PROVIDER: S-EPMC7724822 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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4-Hydroxyisoleucine relieves inflammation through iRhom2-dependent pathway in co-cultured macrophages and adipocytes with LPS stimulation.

Zhou Cong C Chen Rui R Gao Feng F Zhang Jiaoyue J Lu Furong F

BMC complementary medicine and therapies 20201209 1

<h4>Background</h4>4-Hydroxyisoleucine (4-HIL) is an active ingredient extracted from Trigonella foenum-graecum L., a Chinese traditional herbal medicine, which exerts the efficacy of anti-obesity and anti-diabetes. We previously reported that 4-HIL potentiates anti-inflammatory and anti-insulin resistance effects through down-regulation of TNF-α and TNF-α converting enzyme (TACE) in 3 T3-L1 adipocytes and HepG2 cells. In the present study, we further investigate the effects and mechanisms of 4- ...[more]

PMID: 33298044

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Dataset Information

4-Hydroxyisoleucine relieves inflammation through iRhom2-dependent pathway in co-cultured macrophages and adipocytes with LPS stimulation.

Publications

4-Hydroxyisoleucine relieves inflammation through iRhom2-dependent pathway in co-cultured macrophages and adipocytes with LPS stimulation.

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