In vitro antioxidant and anti-aging properties of swim bladder peptides from Atlantic cod (Gadus morhua)

Novel Peptide Derived from Gadus morhua Stimulates Osteoblastic Differentiation and Mineralization through Wnt/β-Catenin and BMP Signaling Pathways

Marine biodiversity offers a wide array of active ingredient resources. Gadus morhua peptides (GMPs) showed excellent osteoprotective effects in ovariectomized mice. However, the potential osteogenesis mechanisms of key osteogenic peptides in GMP were seldom reported. In this study, a novel osteogenic peptide (GETNPADSKPGSIR, P-GM-2) was screened from GMP. P-GM-2 has a high stability coefficient and a strong interaction with epidermal growth factor receptor. Cell culture experiments showed that P-GM-2 stimulated the expression of osteogenic differentiation markers to promote osteoblast proliferation, differentiation, and mineralization. Additionally, P-GM-2 phosphorylates GSK-3β, leading to the stabilization of β-catenin and its translocation to the nucleus, thus initiating the activation of the Wnt/β-catenin signaling pathway. Meanwhile, P-GM-2 could also regulate the osteogenic differentiation of preosteoblasts by triggering the BMP/Smad and mitogen-activated protein kinase signaling pathways. Further validation with specific inhibitors (ICG001 and Noggin) demonstrated that the osteogenic activity of P-GM-2 was revealed by the activation of the BMP and Wnt/β-catenin pathways. In summary, these results provide theoretical and practical insights into P-GM-2 as an effective antiosteoporosis active ingredient.

Swim bladder-derived biomaterials: structures, compositions, properties, modifications, and biomedical applications

Animal-derived biomaterials have been extensively employed in clinical practice owing to their compositional and structural similarities with those of human tissues and organs, exhibiting good mechanical properties and biocompatibility, and extensive sources. However, there is an associated risk of infection with pathogenic microorganisms after the implantation of tissues from pigs, cattle, and other mammals in humans. Therefore, researchers have begun to explore the development of non-mammalian regenerative biomaterials. Among these is the swim bladder, a fish-derived biomaterial that is rapidly used in various fields of biomedicine because of its high collagen, elastin, and polysaccharide content. However, relevant reviews on the biomedical applications of swim bladders as effective biomaterials are lacking. Therefore, based on our previous research and in-depth understanding of this field, this review describes the structures and compositions, properties, and modifications of the swim bladder, with their direct (including soft tissue repair, dural repair, cardiovascular repair, and edible and pharmaceutical fish maw) and indirect applications (including extracted collagen peptides with smaller molecular weights, and collagen or gelatin with higher molecular weights used for hydrogels, and biological adhesives or glues) in the field of biomedicine in recent years. This review provides insights into the use of swim bladders as source of biomaterial; hence, it can aid biomedicine scholars by providing directions for advancements in this field.

Anti-aging effect of peptides on Caenorhabditis elegans: a meta-analysis

BACKGROUND

Recently, peptides have been studied in Caenorhabditis elegans for anti-aging research. Due to the lack of sufficient evidence, we conducted this meta-analysis focusing on the anti-aging effect of peptides in C. elegans to provide more convincing evidence.

RESULTS

A literature search in PubMed, SCOUPUS, and Web of Science databases yielded 2879 articles. After removing duplicates and based on inclusion criteria and STAIR checklist quality assessment, nine articles were selected. Data extraction and analysis showed that, compared to the control group without peptide intervention, peptide supplementation significantly reduced nematode mortality risk [hazard ratio = 0.54, 95% confidence interval (CI) = 0.47, 0.62; P < 0.05], significantly increased the pharyngeal pumping rate [standardized mean difference (SMD) = 1.64, 95% CI = 0.87, 2.41; P < 0.05], bending frequency (SMD = 1.67, 95% CI = 1.16, 2.18; P < 0.05), and significantly decreased the accumulation of lipofuscin levels within nematodes (SMD = -4.48, 95% CI = -6.85, -2.12; P < 0.05). Additionally, subgroup analysis showed that doses ranging from 0.1 to 1 mg/mL (HR = 0.50, 95% CI = 0.38, 0.65; P < 0.05) displayed better anti-aging effects compared to other dose ranges.

CONCLUSION

The findings suggest that peptides can significantly extend the lifespan of C. elegans under normal circumstances and improve three indicators of healthy life. More importantly, subgroup analysis revealed that a dosage of 0.1-1 mg/mL demonstrated superior anti-aging effects. This meta-analysis provides more convincing evidence that peptides can play an anti-aging role in C. elegans. © 2024 Society of Chemical Industry.

Marine Bioactive Peptides: Anti-Photoaging Mechanisms and Potential Skin Protective Effects

Skin photoaging, resulting from prolonged exposure to ultraviolet radiation, is a form of exogenous aging that not only impacts the aesthetic aspect of the skin but also exhibits a strong correlation with the onset of skin cancer. Nonetheless, the safety profile of non-natural anti-photoaging medications and the underlying physiological alterations during the process of photoaging remain inadequately elucidated. Consequently, there exists a pressing necessity to devise more secure interventions involving anti-photoaging drugs. Multiple studies have demonstrated the noteworthy significance of marine biomolecules in addressing safety concerns related to anti-photoaging and safeguarding the skin. Notably, bioactive peptides have gained considerable attention in anti-photoaging research due to their capacity to mitigate the physiological alterations associated with photoaging, including oxidative stress; inflammatory response; the abnormal expression of matrix metalloproteinase, hyaluronidase, and elastase; and excessive melanin synthesis. This review provides a systematic description of the research progress on the anti-photoaging and skin protection mechanism of marine bioactive peptides. The focus is on the utilization of marine bioactive peptides as anti-photoaging agents, aiming to offer theoretical references for the development of novel anti-photoaging drugs and methodologies. Additionally, the future prospects of anti-aging drugs are discussed, providing an initial reference for further research in this field.

Isolation, Identification, and Biological Activity Analysis of Swim Bladder Polypeptides from Acipenser schrencki

Swim bladder polypeptides (SBPs) of Acipenser schrencki were analyzed for their antioxidant activity and physicochemical properties. The results showed the optimal enzymatic conditions were alkaline protease with a solid-to-liquid ratio of 1:20, an incubation time of 4 h, a temperature of 55 °C, and an enzyme dosage of 5000 U/g. Three different molecular weight fractions (F1, F2, and F3) were obtained via ultrafiltration. F3 (912.44-2135.82 Da) showed 77.90%, 72.15%, and 66.25% removal of O₂•^-, DPPH•, and •OH, respectively, at 10 mg/mL, which was significantly higher than the F1 and F2 fractions (p < 0.05). F3 contained proline (6.17%), hydroxyproline (5.28%), and hydrophobic amino acids (51.39%). The UV spectrum of F3 showed maximum absorption at 224 nm. Peptide sequence analysis showed that F3 contained antioxidant peptides (MFGF, GPPGPRGPPGL, and GPGPSGERGPPGPM) and exhibited inhibitory activities on angiotensin-converting enzyme and dipeptidyl peptidase III/IV (FRF, FPFL and LPGLF). F3 was considered a good raw material for obtaining bioactive peptides.

Anticoagulant and anti-inflammatory effects of a degraded sulfate glycosaminoglycan from swimming bladder

Low molecular weight sulfate glycosaminoglycan has attracted more attention recently for its great bioactivity. In the present study, a degraded sulfate glycosaminoglycan (named D-SBSG) was prepared from swimming bladder by enzymatic depolymerization, the structure characteristics of D-SBSG and its effects on blood coagulation and inflammation in vitro was investigated. HPGPC analysis showed that the molecular weight (Mw) of SBSG was 115.84 kDa, while the Mw of D-SBSG was 4.96 kDa. The bioactivities had arose dramatic differences, though its main molecule structure had little change after enzymatic degradation. Compared with heparin sodium, relatively milder anticoagulant activity in vitro, which were positively associated with molecular weight, were found in SBSG and D-SBSG. In contrast, the results of anti-inflammatory assays indicated that D-SBSG with the lower molecular weight possessed higher bioactivity than SBSG. Additionally, the D-SBSG inhibited the LPS-induced inflammatory in RAW264.7 macrophages by down-regulation of inflammatory mediators, both of NF-κB (including p65) and MAPK (including p38) signaling pathways to exert its anti-inflammatory function. These results indicated that enzymolysis is a viable strategy for degradation of sulfate glycosaminoglycan, and D-SBSG could be a promising ingredient for inflammation management.

Recent Progress in Antioxidant Active Substances from Marine Biota

Background: The well-recognized but not fully explored antioxidant activity of marine-biota-derived, biologically active substances has led to interest in their study as substitutes of antibiotics, antiaging agents, anticancer and antiviral drugs, and others. The aim of this review is to present the current state of the art of marine-biota-derived antioxidants to give some ideas for potential industrial applications. Methods: This review is an update for the last 5 years on the marine sources of natural antioxidants, different classes antioxidant compounds, and current derivation biotechnologies. Results: New marine sources of antioxidants, including byproducts and wastes, are presented, along with new antioxidant substances and derivation approaches. Conclusions: The interest in high-value antioxidants from marine biota continues. Natural substances combining antioxidant and antimicrobial action are of particular interest because of the increasing microbial resistance to antibiotic treatments. New antioxidant substances are discovered, along with those extracted from marine biota collected in other locations. Byproducts and wastes provide a valuable source of antioxidant substances. The application of optimized non-conventional derivation approaches is expected to allow the intensification of the production and improvement in the quality of the derived substances. The ability to obtain safe, high-value products is of key importance for potential industrialization.

Role of bioactive peptides derived from food proteins in programmed cell death to treat inflammatory diseases and cancer

Bioactive peptides are specific peptide which usually contains 2-20 amino acid residues and actively exerts various functions and biological activities and ultimately affect health. Programmed cell deaths are some styles of cell death discovered in recent years, which is the key to tissue development and balance, eliminating excess, damaged or aging cells. More importantly, programmed cell death is a potential way to treat inflammatory diseases and cancer. In this review, through screening references from 2015 to present, we introduce the effect of bioactive peptides derived from food proteins on inflammatory diseases or cancer through regulating programmed cell deaths, including apoptosis, autophagy, pyroptosis, ferroptosis, and necroptosis. And this review also introduces the targets of these bioactive peptides to regulate programmed cell death. The purpose of this review is to help to expand the prospective applications of bioactive peptides in the field of inflammatory disease and cancer to provide some guidance.