Peptides Released from Extruded Adzuki Bean Protein through Simulated Gastrointestinal Digestion Exhibit Anti-inflammatory Activity

Abstract

Increasing attention has been focused on plant-derived peptides because of their potential bioactivities. In this study, bioactive peptides were released from extruded adzuki bean protein by simulated gastrointestinal digestion. A peptide (KQS-1) sequenced as KQSESHFVDAQPEQQQR was separated and identified using ultrafiltration, pre-high-performance liquid chromatography (HPLC), and ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). KQS-1 was shown to exert significant anti-inflammatory effects in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages by reducing the production of IL-1, IL-6, TNF-α, and MCP-1 to 38.31, 6.07, 43.96, and 41.74%, respectively. The involved signaling pathways were identified by transcriptome analysis. Overall, 5236 differentially expressed genes (DEGs) were identified. Gene ontology (GO) functions demonstrated that DEGs were significantly related to the NF-κB pathway. In conclusion, KQS-1 prevented the activation and expression of NF-κB/caspase-1 by upstream and downstream factors. These findings highlight the bioactivity of adzuki bean peptides.

A Yeast-Derived Peptide Promotes Skin Wound Healing by Stimulating Effects on Fibroblast and Immunomodulatory Activities

“…For example anti-inflammatory peptides VPP and IPP resulting from bacterial fermentation of milk, IRW and IQW obtained from egg casein, and PAY isolated from salmon byproduct protein, and PTGADY from Alaska pollock protein [10] have molecular weight less than 1 kDa [26]. The exact relationship between peptide size and its anti-inflammatory activity is not well-established, but some reports attributed the higher anti-inflammatory of small-sized peptides to the easier absorbance by immune cells [12]. Peptides that penetrate cells usually have a sequence length of 5 to 42 amino acids [27].…”

“…Although it is well-established that the biological activities of peptides depend on their molecular weight and amino acid sequences, the link between the structure and function is not fully understood [5]. Small peptides below 1 KDa derived from different sources such as IPP and VPP from fermented milk [5], IRW and IQW from egg protein [6,7], PLV and VPY from soy protein [8,9], PTGADY from Alaska pollock protein [10], and PAY from salmon protein [11] can be absorbed by immune and skin cells and modulate cell functions [12]. In these peptides, hydrophobic amino acids are the key players in their anti-inflammatory activity and proliferative properties on fibroblasts.…”

Cooked Adzuki Bean Reduces High-Fat Diet-Induced Body Weight Gain, Ameliorates Inflammation, and Modulates Intestinal Homeostasis in Mice

“…Adzuki bean dietary fiber reduced visceral fat accumulation in rats fed a normal diet ( 15 ). The biologically active peptides in adzuki bean exhibited significant anti-inflammatory activity by inhibiting the expression of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) ( 16 ). In addition, adzuki bean water extract containing polyphenols attenuated obesity by regulating gut microbiota ( 17 ).…”

Casein Oligochitosan-Glycation by Transglutaminase Enhances the Anti-Inflammatory Potential of Casein Hydrolysates to the Lipopolysaccharide-Stimulated IEC-6 Cells

“…It is recognized that inflammation is associated with many chronic diseases such as cancer, obesity, and gastrointestinal diseases. Fortunately, several food components, such as proteins [ 16 ], polysaccharides [ 17 ], and polyphenols, [ 18 ] are proven to have an ability to antagonize the induced inflammation. It was found that mung bean protein hydrolysates [ 19 ], sturgeon protein-derived peptides [ 20 ], and sea buckthorn flavonoids [ 21 ] were able to regulate the expression of inflammatory markers in the LPS-stimulated RAW 264.7 macrophages and then activate the relevant signaling pathways to exert an anti-inflammatory effect.…”