Antioxidant and Anti-Inflammatory Properties of Rubber Seed Oil in Lipopolysaccharide-Induced RAW 267.4 Macrophages

Protective effect of rubber seed oil on human endothelial cells

OBJECTIVE

This study was conducted to characterize the antioxidant and anti-inflammatory properties of Rubber Seed Oil (RSO) against atherosclerosis (AS) through the study of the protective effects and mechanisms on human umbilical vein endothelial cells (HUVECs) injury induced by oxidized low-density lipoprotein (ox-LDL).

METHODS

HUVECs were treated with RSO, ox-LDL, RSO + ox-LDL, respectively, followed by cell activity testing, levels of IL-1β, IL-6, IL-10, TNF-α, ROS, NO, the mRNA expression of eNOS and protein expression of MCP-1, VCAM-1, eNOS, TLR4, NF-κB p65、p-NF-κB p65.

RESULTS

Compared with the ox-LDL group, cell viability, NO level and the expression of eNOS mRNA significantly increased. and the levels of pro-inflammatory factors such as IL-1β, IL-6, TNF-α, IL-10, ROS were significantly decreased, which was accompanied by decreases in TLR4 mRNA, TLR4, MCP-1, VCAM-1 protein expression, as well as the ratio of NF-κB p-p65/p65 in the group treated with 250 μg/ml ox-LDL + 50 μg/ml RSO, 250 μg/ml ox-LDL + 100 μg/ml RSO, 250 μg/ml ox-LDL + 150 μg/ml RSO.

CONCLUSIONS

RSO can reduce the expression of pro-inflammatory mediators, oxidative factors involved in injured vascular endothelial cells, exhibiting anti-inflammatory and antioxidant properties HUVECs exposed to ox-LDL. In addition, it may alleviate endothelial cell damage by inhibiting the TLR4/NF-κB signaling pathway.

Effects of fatty acid-ethanol amine (FA-EA) derivatives on lipid accumulation and inflammation

This study aimed to investigate the effect of fatty acid-ethanol amine (FA-EA) derivatives (L1-L10) on the mitigation of intracellular lipid accumulation and downregulation of pro-inflammatory cytokines in vitro. First, the series of FA-EA derivatives were synthesized and characterized. Then, their cytotoxic, intracellular lipid accumulation and inhibition of pro-inflammatory cytokines were evaluated. The oil red O staining experiment showed that the tested compounds L4, L6, L8, L9, and L10 could reduce intracellular lipid accumulation induced by palmitic acid (PA). Moreover, ω-3/ω-6 PUFA-EA derivatives showed inhibitory effect on the production of pro-inflammatory cytokines in lipopolysaccharide (LPS) -stimulated RAW 264.7 cells. ω-3/ω-6 PUFA-EA derivatives at a concentrations of 10 μM could significantly decrease mRNA levels of IL-6, IL-1β, and TNF-α, inhibit NO production, and alleviate the protein expression of IL-1β in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. These data suggest that ω-3 PUFA-EA derivatives can be beneficial for further pharmaceutical development to treat chronic low-grade inflammation diseases such as obesity.

Protective effect of wogonin on inflammatory responses in BisGMA-treated macrophages through the inhibition of MAPK and NFκB pathways

Composites, resins, and sealants that are commonly used in orthopedics and dentistry are based on 2,2-bis[p-(2'-hydroxy-3'-methacryloxypropoxy)phenylene]propane (BisGMA), which induces proinflammatory responses in macrophages. The present study aimed to explore the anti-inflammatory responses of wogonin, which is a natural dihydroxyl flavonoid compound, in BisGMA-treated macrophages. According to the findings, wogonin exhibits anti-inflammatory, antiallergic, anticancer, and antioxidative properties. The generation of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS) were noted to be inhibited by wogonin in BisGMA-treated macrophages. Furthermore, the production of proinflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 was reduced. In addition, BisGMA-induced nuclear factor (NF)-κB p65 phosphorylation and inhibitor of κB (IκB) degradation were inhibited. Finally, the BisGMA-induced phosphorylation of mitogen-activated protein kinases (MAPKs), including p38 MAPK, extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) was inhibited. All these effects were induced by wogonin in the macrophages in a concentration-dependent manner. Similar inhibitory effects of wogonin were observed on the production of NO and proinflammatory cytokines, expression of iNOS, phosphorylation of NF-κB p65 and MAPK, and degradation of IκB. These results indicated that rutin is a potential anti-inflammatory agent for BisGMA-treated macrophages that undergo NFκB p65 phosphorylation and IκB degradation through upstream MAPK phosphorylation. Therefore, wogonin inhibits BisGMA-induced proinflammatory responses in macrophages through the regulation of the NFκB pathway and its upstream factor, MAPK.

Rubber (Hevea brasiliensis) seed oil supplementation attenuates immunological stress and inflammatory response in lipopolysaccharide-challenged laying hens

This study was conducted to investigate the effect of PUFA-enriched rubber (Hevea brasiliensis) seed oil (RSO) supplementation in diets on the productive performance, plasma biochemical parameters, immune response, and inflammation in lipopolysaccharide (LPS)-challenged laying hens. Two hundred and forty 25-wk-old Lohmann Brown laying hens were randomly divided into 5 treatments, each including 4 replicates with 12 birds per replicate. The control group and LPS-challenged group were fed a corn-soybean-basal diet; 3 RSO-supplemented groups were fed experimental diets containing 1, 2, and 4% RSO for a feeding period of 4 wk. On the 15, 18, 21, 24, and 27 d of the RSO supplementation period of 4 wk, hens were injected intraperitoneally with LPS at 1 mg/kg body weight (challenge group and RSO-supplemented groups) or with the same amount of saline (control group). The results showed that the addition of RSO promoted laying performance by increasing egg production, total egg weight, daily egg mass, and feed intake in comparison to the LPS-challenged laying hens (P < 0.05). In addition, compared with laying hens stimulated with LPS, the analysis of blood cell and plasma parameters revealed that hens in RSO-supplemented groups had significantly lower levels (P < 0.05) of white blood cells (WBC), lymphocytes (LYM), aspartate aminotransferase (AST) activity, immunoglobulin A (IgA), triiodothyronine (T3), interleukin-2 (IL-2), and tumor necrosis factor-α (TNF-α). Further, RSO supplementation significantly reduced the mRNA expression of toll-like receptor 4 (TLR4), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), interleukin-6 (IL-6), and interleukin-1β (IL-1β) of the ileum, spleen, and liver in LPS-challenged laying hens (P < 0.05), suggesting that the anti-inflammatory mechanism of RSO is related to the TLR4/NF-κB signaling pathway. In conclusion, RSO supplementation in diets could improve laying performance, attenuate immunological stress, and inhibit the inflammatory response in LPS-challenged laying hens, especially at the dietary inclusion of 4% RSO. This study will provide an insight into the application of RSO to positively contribute to overall health and welfare in laying hens.

Salecan ameliorates liver injury by regulating gut microbiota and its metabolites

Salecan ameliorates liver injury by regulating oxidative stress and the gut microbiota.