Novel Peptide Derived from Gadus morhua Stimulates Osteoblastic Differentiation and Mineralization through Wnt/ß-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-3ß, leading to the stabilization of ß-catenin and its translocation to the nucleus, thus initiating the activation of the Wnt/ß-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/ß-catenin pathways. In summary, these results provide theoretical and practical insights into P-GM-2 as an effective antiosteoporosis active ingredient.

Oyster ferritin can efficiently alleviate ROS-mediated inflammation attributed to its unique micro-environment around three-fold channels.

The conversion of toxic Fe2+ into non-toxic Fe3+ stored in the inner cavity of ferritin nanocage could effectively reduce the occurrence of the Fenton reaction and inhibit the formation of harmful reactive oxygen species (ROS). In this study, we reveal that oyster ferritin (GF1) can rely on its high catalytic activity (7.7 times that of rHuHF) and high binding ability of Fe2+ (9.1 times that of rHuHF) to reduce the precursors of Fenton reaction, thus inhibiting the occurrence of Fenton reaction and slowing down reactive oxygen species-mediated inflammation. The above significant advantage of GF1 can be attributed to the Asp at the position 120th, which could increase the negatively charged area of three-fold channels from 37.8% (rHuHF) to 67.8% and then enhance its oxidation rate and ability of GF1. The findings are of great value in advancing novel nanoparticle drug design based on crystalline structure.

Crassostrea gigas-Based Bioactive Peptide Protected Thrombin-Treated Endothelial Cells against Thrombosis and Cell Barrier Dysfunction.

The activation of thrombin-treated endothelial cells resulted in disruption of the vascular tissues. A novel oyster-derived bioactive dodecapeptide (IEELEELEAER, P-2-CG) was reported to protect the human umbilical vein endothelial cells and their barrier function via the decrease of VE-cadherin disruption and the restoration of the F-actin arrangement. The promotion of the extrinsic pathway in this case triggers the release of tissue factors that occurs on the surface of the endothelial cells, thus changing the antithrombotic to prothrombotic. P-2-CG induced accordingly a prolongation of plasma clotting time and thrombin generation time, following the alteration of the antithrombotic phenotype. Furthermore, the antithrombotic activity of P-2-CG was also supported by the reduction of FXa and the inhibition of other factors release, for instance, inflammation factors, ROS, etc. In addition to its antithrombogenic role, P-2-CG displayed anti-inflammatory and antioxidant properties via the mitogen-activated protein kinase cascades and central signaling pathways as shown in an in vitro model of endothelial dysfunction.

Advancements of nature nanocage protein: preparation, identification and multiple applications of ferritins.

Ferritin is an important iron storage protein, which is widely existed in all forms of life. Ferritin can regulate iron homeostasis when iron ions are lacking or enriched in the body, so as to avoid iron deficiency diseases and iron poisoning. Ferritin presents a hollow nanocage, which can store ions or other small molecular substances in the cavity. Therefore, ferritin shows its potential as a functional nanomaterial that can deliver nutrients or drugs in a targeted manner to improve bioavailability. Due to the special structure, the research on ferritin has attracted more and more attention in recent years. In this paper, the structural characteristics of ferritin were introduced, and the natural purification and prokaryotic expression methods of ferritin from different sources were described. At the same time, ferritin can bind to small molecules, so that it has the activity of small molecules, to construct a new type of ferritin. As a result, ferritin plays an important role as a nutrient substance, in targeted transport, and disease monitoring, etc. In conclusion, the yield of ferritin can be improved by means of molecular biology. Meanwhile, molecular modification can be used to make ferritin have unique activity and function, which lays a foundation for subsequent research.HighlightsThe molecular and structural properties of ferritins were clearly described.Isolation and purification technologies of ferritin were compared.Characterization, functions and molecular modifications mechanism of ferritin were reviewed.The applications of ferritin in pharmaceutical and food industry were prospected.

Absorption and transport of a Mytilus edulis-derived peptide with the function of preventing osteoporosis.

The YPRKDETGAERT peptide (PME-1) identified from the Mytilus edulis proteins has been shown to promote the proliferation and differentiation of osteoblasts and it has good bone-forming activity in vitro. Further, PME-1 has been shown to prevent osteoporosis in vivo. PME-1 can be absorbed through the gastrointestinal tract, and the passing rate in monolayer Caco-2 cells was 6.57%. PME-1 can also enter the blood circulation and the concentration of PME-1 in serum reached the maximum, 61.06 ± 26.32 ng mL-1, 20 min after feeding. The multifunctional in vivo imager was used to further determine the distribution of the 5-FITC-(Acp)-YPRKDETGAERT peptide (PME-1-FITC) 2 h after feeding the peptide, and the result confirmed the above results and showed that a part of PME-1-FITC can affect bone in vivo. Therefore, PME-1 not only was easily absorbed in the gastrointestinal tract, but also has the potential beneficial effect on preventing osteoporosis.

High throughput analysis and quantitation of α-dicarbonyls in biofluid by plasmonic nanoshells enhanced laser desorption/ionization mass spectrometry.

Advanced analytical platforms are required for accurate detection and quantification of small molecular substances exhibiting certain toxicity. Small molecules detection in complex biological fluids are challenged by the complexity of the samples and the low throughput of the existing methods. In the present study, to detect a batch of samples (50) in 1 h, the plasmonic nanoshell enhanced matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS) was tested. The limit of quantification (LOQ) was determined as 0.01 µg/mL (for α-dicarbonyl compounds) by vortex-assisted liquid-liquid microextraction (VALLME). The developed method can be adopted to study the high-throughput metabolomics and employed for clinical precision diagnosis with MALDI-TOF MS.

Pharmacokinetics and Transport of an Osteogenic Dodecapeptide.

A dodecapeptide with the amino acid sequence of IEELEEELEAER (PIE), identified from Mytilus edulis proteolysis hydrolysates, has shown good bone-forming activity in previous studies. The pharmacokinetics and transport of the PIE peptide in vivo or in vitro were investigated in this study. The results showed that the PIE peptide can be transported into monolayer Caco-2 cells, and the PIE peptide was identified in the serum after the mice reached the highest value of 173.60 ± 60.30 ng/mL, in which it was quantified by an optimized mass spectrometry method. In addition, the PIE peptide has a promoting effect on the bone morphogenetic protein pathway at the gene and protein levels. According to the distribution of PIE-FITC in ovariectomized mice after orally administrated PIE-FITC, it was confirmed that it can enter the gastrointestinal tract and serum, and reach the bones. Taken together, the PIE peptide can be absorbed well both in vitro and in vivo, and it could promote pre-osteoblast differentiation factors.

CYTOTOXIC EFFECTS OF THE RED SEA SOFT CORAL SARCOPHYTON TROCHELIOPHORUM.

The present study describes the in vitro cytotoxic effects of soft coral (Sarcophyton tiocheliophorum). Soft corals of genus Sarcophyton were reported to contain compounds that are active against brine shrimp and promote paclitaxel cytotoxicity in the human colon cancer Caco-2 cell line. The n-hexane extract of the soft coral Sarcophyton tiocheliophorum induced significant dose-dependent toxicity (LC50 96.7 ppm) compared with ethyl acetate (LC50. 120 ppm). We reported the most active cytotoxic level to be correspondence to LC50 values of 20.2, 59.2 ppm and 18.9 and 26 ppm. Accordingly, bio-assay guided fractionation was conducted to identi- fy the bioactive compounds. Arachidonic acid, eicosapentaenoic acid and docosahexaenoic acid were characterized based on GC-MS analyses. Our results demonstrate the value of marine products as a natural source of medicinally interesting cytotoxic compounds.