Docosahexaenoic Acid Ameliorates the Toll-Like Receptor 22-Triggered Inflammation in Fish by Disrupting Lipid Raft Formation.
J Nutr
; 152(8): 1991-2002, 2022 08 09.
Article
en En
| MEDLINE
| ID: mdl-35679100
ABSTRACT
BACKGROUND:
Although dietary DHA alleviates Toll-like receptor (TLR)-associated chronic inflammation in fish, the underlying mechanism is not well understood.OBJECTIVES:
This study aimed to explore the role of Tlr22 in the innate immunity of large yellow croaker and investigate the anti-inflammatory effects of DHA on Tlr22-triggered inflammation.METHODS:
Head kidney-derived macrophages of croaker and HEK293T cells were or were not pretreated with 100 µM DHA for 10 h prior to polyinosinic-polycytidylic acid (poly IC) stimulation. We executed qRT-PCR, immunoblotting, and lipidomic analysis to examine the impact of DHA on Tlr22-triggered inflammation and membrane lipid composition. In vivo, croakers (12.03 ± 0.05 g) were fed diets containing 0.2% [control (Ctrl)], 0.8%, and 1.6% DHA for 8 wk before injection with poly IC. Inflammatory genes expression and rafts-related lipids and protein expression were measured in the head kidney. Data were analyzed by ANOVA or Student t test.RESULTS:
The activation of Tlr22 by poly IC induced inflammation, and DHA diminished Tlr22-targeted inflammatory gene expression by 56-73% (P ≤ 0.05). DHA reduced membrane sphingomyelin (SM) and SFA-containing phosphatidylcholine (SFA-PC) contents, as well as lipid raft marker caveolin 1 amounts. Furthermore, lipid raft disruption suppressed Tlr22-induced Nf-κb and interferon h activation and p65 nuclear translocation. In vivo, expression of Tlr22 target inflammatory genes was 32-64% lower in the 1.6% DHA group than in the Ctrl group upon poly IC injection (P ≤ 0.05). Also, the 1.6% DHA group showed a reduction in membrane SM and SFA-PC contents, accompanied by a decrease in caveolin 1 amounts, compared with the Ctrl group.CONCLUSIONS:
The activation of Tlr22 signaling depends on lipid rafts, and DHA ameliorates the Tlr22-triggered inflammation in both head kidney and head kidney-derived macrophages of croaker partially by altering membrane SMs and SFA-PCs that are required for lipid raft organization.Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Perciformes
/
Ácidos Docosahexaenoicos
Límite:
Animals
/
Humans
Idioma:
En
Año:
2022
Tipo del documento:
Article