Sophorolipid Suppresses LPS-Induced Inflammation in RAW264.7 Cells through the NF-κB Signaling Pathway

Abstract

Objectives: Biosurfactants with anti-inflammatory activity may alleviate skin irritation caused by synthetic surfactants in cleaning products. Sophorolipid (SL) is a promising alternative to synthetic surfactants. However, there are few reports on the anti-inflammatory activity of SL and the underlying mechanism. The purpose of this work is to verify that lipopolysaccharide (LPS)-induced inflammation could be inhibited through targeting the pathway of nuclear factor-κB (NF-κB) in RAW264.7 cells. Methods: The influence of SL on cytokine release was investigated by LPS-induced RAW264.7 cells using ELISA. The quantification of the protein expression of corresponding molecular markers was realized by Western blot analysis. Flow cytometry was employed to determine the levels of Ca2+ and reactive oxygen species (ROS). The relative expression of inducible nitric oxide synthase (INOS) and cyclooxygenase-2 (COX-2) was determined by RT-PCR. An immunofluorescence assay and confocal microscope were used to observe the NF-κB/p65 translocation from the cytoplasm into the nucleus. The likely targets of SL were predicted by molecular docking analysis. Results: SL showed anti-inflammatory activity and reduced the release of inflammatory cytokines including interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and nitric oxide (NO). The experimental results show that SL suppressed the Ca2+ and ROS levels influx in the LPS-induced RAW264.7 cells and alleviated the LPS-induced expression of iNOS and COX-2, the LPS-induced translocation of NF-κB (p65) from the cytoplasm into the nucleus, and the expression of phosphorylated proteins such as p65 and IκBα. Furthermore, molecular docking analysis showed that SL may inhibit inflammatory signaling by competing with LPS to bind TLR4/MD-2 through hydrophobic interactions and by inhibiting IKKβ activation through the hydrogen bonding and hydrophobic interactions. Conclusion: This study demonstrated that SL exerted anti-inflammatory activity via the pathway of NF-κB in RAW264.7 cells.

Sophorolipid inhibits histamine-induced itch by decreasing PLC/IP3R signaling pathway activation and modulating TRPV1 activity

“…A non-pathogenic strain of Candida bombicola (ATCC 22214 from SHBCC) was used to produce SL through a fermentation process, as described in a prior study [22] . Histamine, loratadine, JNJ7777120, and capsaicin were obtained from Aladdin Biochemical Technology Co. Ltd. (Shanghai, China).…”

“…As of late, there has been an upsurge in the number of people searching for biodegradable, natural, and environmentally-friendly ingredients to treat pruritus. Previous studies have shown that Sophorolipids (SLs) have the ability to reduce in ammation, which is attributed to the suppression of the NF-κB pathway and the consequent reduction in the abundance of cyclooxygenase-2 and inducible nitric oxide synthase [21,22] . Our prior investigations demonstrate that SL is effective in suppressing the calcium in ux in RAW264.7 cells treated with LPS [22] .…”

“…Previous studies have shown that Sophorolipids (SLs) have the ability to reduce in ammation, which is attributed to the suppression of the NF-κB pathway and the consequent reduction in the abundance of cyclooxygenase-2 and inducible nitric oxide synthase [21,22] . Our prior investigations demonstrate that SL is effective in suppressing the calcium in ux in RAW264.7 cells treated with LPS [22] . As a result, it can be proposed that SL could have the capacity to inhibit histamine-induced calcium in ux and be further advanced as a treatment for skin issues, such as itching.…”

Limonin Derivatives via Hydrogenation: Structural Identification and Anti-Inflammatory Activity Evaluation

“…The basal medium was Dulbecco's Modified Eagle Medium (DMEM), containing 10% fetal bovine serum (FBS), 2 mmol/L glutamine, 100 µg/mL streptomycin, and 100 U/mL penicillin. An anti-inflammatory bioassay was performed using a similar procedure to that used by Xu et al [17]. Generally, RAW264.7 cells and the compound with specific concentration (20 µM), or the control group, were incubated in the medium (0.125% dimethyl sulfoxide (DMSO)in the DMEM with 10% FBS).…”

Sophorolipid inhibits histamine-induced itch by decreasing PLC/IP3R signaling pathway activation and modulating TRPV1 activity

“…Recently, there has been a surge in the search for biodegradable, natural and environmentally friendly ingredients for the treatment of pruritus. Previous studies have shown that Sophorolipid has the ability to alleviate inflammation, which is attributed to the suppression of the NF-κB pathway and the consequent reduction in the abundance of cyclooxygenase-2 and inducible nitric oxide synthase 24 , 25 . Our previous investigation has demonstrated that SL is effective in suppressing the calcium influx in RAW264.7 cells stimulated with LPS 25 .…”