The alleviative effect of C-phycocyanin peptides against TNBS-induced inflammatory bowel disease in zebrafish via the MAPK/Nrf2 signaling pathways.

INTRODUCTION: Ulcerative colitis (UC) is an incurable and highly complex chronic inflammatory bowel disease (IBD) affecting millions of people worldwide. C-phycocyanin (C-PC) has been reported to possess outstanding anti-inflammatory activities and can effectively inhibit various inflammation-related diseases. Whether C-PC-derived bioactive peptides can inhibit intestinal inflammation is worth research and consideration. METHODS: The inhibition activities of three anti-neuroinflammatory peptides were evaluated using 2-4-6-trinitrobenzen sulfonic acid (TNBS)-induced zebrafish colitis model. Subsequently, the abilities of peptides to promote gastrointestinal motility were also examined. The changes in the intestinal pathological symptoms and ultrastructure of intestinal, reactive oxygen species (ROS) levels, and antioxidant enzymes were then determined after co-treatment with peptides and TNBS. Transcriptome analysis was used to investigate the underlying ameliorating TNBS-induced colitis effects molecular mechanisms of better activity peptide. Furthermore, quantitative reverse-transcription polymerase chain reaction and molecular docking techniques verified the mRNA sequencing results. RESULTS: Three peptides, MHLWAAK, MAQAAEYYR and MDYYFEER, which significantly inhibit macrophage migration, were synthesized. The results showed that these peptides could effectively alleviate the inflammatory responses in the TNBS-induced zebrafish model of colitis. In addition, co-treatment with TNBS and C-PC peptides could decrease ROS production and increase antioxidant enzyme activities in zebrafish larvae. Moreover, MHLWAAK had the most significantly therapeutic effects on colitis in zebrafish. The transcriptome analysis suggests that the effect of MHLWAAK on TNBS-induced colitis may be associated with the modulation of nuclear factor-erythroid 2-related factor 2 (Nrf2) and mitogen-activated protein kinase (MAPK) signaling pathway associated genes. In addition, molecular docking was conducted to study the prospective interaction between peptides and the key proteins that streamline the Nrf2 and MAPK signaling pathways. IL-6, JNK3, TNF-α, KEAP1-NRF2 complex and MAPK may be the core targets of MHLWAAK in treating colitis. CONCLUSION: The results suggested that the three C-PC-derived peptides could ameliorate TNBS-induced colitis in zebrafish, and these peptides might be a promising therapeutic candidate for UC treatment.

Secondary metabolites from the marine-derived fungus Penicillium chrysogenum Y20-2, and their pro-angiogenic activity.

A systematic chemical study of the secondary metabolites of the marine fungus, Penicillium chrysogenum (No. Y20-2), led to the isolation of 21 compounds, one of which is new (compound 3). The structures of the 21 compounds were determined by conducting extensive analysis of the spectroscopic data. The pro-angiogenic activity of each compound was evaluated using a zebrafish model. The results showed that compounds 7, 9, 16, and 17 had strong and dose-dependent pro-angiogenic effects, with compound 16 demonstrating the strongest pro-angiogenic activity, compounds 6, 12, 14, and 18 showing moderate activity, and compounds 8, 13, and 19 exhibiting relatively weak activity.

The molecular mechanism of three novel peptides from C-phycocyanin alleviates MPTP-induced Parkinson's disease-like pathology in zebrafish.

Previous studies have shown that peptides isolated from C-phycocyanin (C-PC) possess various functions including antioxidant and anticancer activities. However, there is little research on C-PC peptides applied for the neuroprotective effect against a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease (PD) model. In this study, twelve novel peptides from C-PC were isolated, purified and identified, and the anti-PD effect of the synthesized peptides was evaluated in a zebrafish PD model. As a result, three of these peptides (MAAAHR, MPQPPAK, and MTAAAR) significantly reversed the loss of dopamine neurons and cerebral vessels, and reduced the locomotor impairment in PD zebrafish. In addition, three novel peptides could inhibit the MPTP-induced decrease of antioxidant enzymes (SOD, CAT, and GSH-Px) and increase the ROS and protein carbonylation content. In addition, they can also alleviate apoptosis of brain regions and acetylcholinesterase (AChE) activity in zebrafish. Further studies elucidated the potential molecular mechanism of peptides' anti-PD effects in the larvae. The results showed that C-PC peptides could modulate multiple genes associated with oxidative stress, autophagy and apoptosis signaling pathways, and thereby alleviate the occurrence of PD symptoms. Overall, our results highlight the neuroprotective effects of three novel peptides and provide valuable mechanistic insights and a promising drug target for the treatment of PD.

Lipid Profiles of the Heads of Four Shrimp Species by UPLC-Q-Exactive Orbitrap/MS and Their Cardiovascular Activities.

Lipids are key factors in nutrition, structural function, metabolic features, and other biological functions. In this study, the lipids from the heads of four species of shrimp (Fenneropenaeus chinensis (FC), Penaeus japonicus (PJ), Penaeus vannamei (PV), and Procambarus clarkia (PCC)) were compared and characterized based on UPLC-Q-Exactive Orbitrap/MS. We compared the differences in lipid composition of four kinds of shrimp head using multivariate analysis. In addition, a zebrafish model was used to evaluate pro-angiogenic, anti-inflammatory, anti-thrombotic, and cardioprotective activities of the shrimp head lipids. The lipids from the four kinds of shrimp head had different degrees of pro-angiogenic activities, and the activities of PCC and PJ shrimp lipids were more significant than those of the other two species. Four lipid groups displayed strong anti-inflammatory activities. For antithrombotic activity, only PCC (25 µg/mL) and PV (100 µg/mL) groups showed obvious activity. In terms of cardioprotective activity, the four kinds of lipid groups significantly increased the zebrafish heart rhythms. The heart distances were shortened, except for those of the FC (100 µg/mL) and PJ (25 µg/mL) groups. Our comprehensive lipidomics analysis and bioactivity study of lipids from different sources could provide a basis for the better utilization of shrimp.