Marine Skeletal Biopolymers and Proteins, and Their Biomedical Application

A special issue of Marine Drugs (ISSN 1660-3397).

Deadline for manuscript submissions: closed (31 March 2021) | Viewed by 59753

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Special Issue Editor

Special Issue Information

Dear Colleagues,

Marine skeletal proteins and biopolymers have a great potential application in the medical field. The skeletal biopolymers include chitin and chitosan, collagen, cellulose, and various polysaccharides. The marine skeletal proteins, for instance, calcium-binding proteins, marine enzymes, and various candidate proteins for drug discovery from the calcifying marine organisms. Due to their broad spectrum of biological functions into biopolymer and protein-based drugs and bioactivities, such as anticancer, antimicrobial, bone tissue regeneration, antioxidant, and anti-aging activities, bioactive skeletal proteins and biopolymer have recently gained a great amount of interest in the pharmaceutical, nutraceutical, and cosmeceutical industries. Marine skeletal proteins are also a very rich source of amino acids, which are essential for building good health.

Researchers around the world have found that the biopolymers, proteins, and peptides extracted from marine calcifiers are the most convenient and safest sources. The advantages of this source are the huge availability and abundance in the shallow, mid-level, and deep-sea waters. This source includes marine invertebrates and related calcifiers, for example, soft and hard corals, mollusks/bivalves, sponges, sea urchins, coralline red algae, and other calcifying marine organisms.

Dr. Azizur Rahman
Guest Editor

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Keywords

  • Marine proteins and peptides
  • Biopolymers
  • Corals
  • Sponges
  • Sea urchins
  • Mollusks/Bivalves
  • Marine algae
  • Marine Collagen
  • Marine Chitin
  • Marine polysaccharides
  • Marine bioactive compounds
  • Marine Biotechnology
  • Marine biomaterials
  • Proteomics

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Published Papers (14 papers)

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Editorial

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4 pages, 189 KiB  
Editorial
Marine Skeletal Biopolymers and Proteins and Their Biomedical Application
by M. Azizur Rahman
Mar. Drugs 2021, 19(7), 389; https://doi.org/10.3390/md19070389 - 12 Jul 2021
Cited by 3 | Viewed by 2350
Abstract
Skeletal biopolymers and proteins in marine organisms are present as complex mixtures and have great potential applications in the biomedical field [...] Full article

Research

Jump to: Editorial

16 pages, 3833 KiB  
Article
Collagen Peptides from Swim Bladders of Giant Croaker (Nibea japonica) and Their Protective Effects against H2O2-Induced Oxidative Damage toward Human Umbilical Vein Endothelial Cells
by Jiawen Zheng, Xiaoxiao Tian, Baogui Xu, Falei Yuan, Jianfang Gong and Zuisu Yang
Mar. Drugs 2020, 18(8), 430; https://doi.org/10.3390/md18080430 - 18 Aug 2020
Cited by 27 | Viewed by 3478
Abstract
Five different proteases were used to hydrolyze the swim bladders of Nibea japonica and the hydrolysate treated by neutrase (collagen peptide named SNNHs) showed the highest DPPH radical scavenging activity. The extraction process of SNNHs was optimized by response surface methodology, and the [...] Read more.
Five different proteases were used to hydrolyze the swim bladders of Nibea japonica and the hydrolysate treated by neutrase (collagen peptide named SNNHs) showed the highest DPPH radical scavenging activity. The extraction process of SNNHs was optimized by response surface methodology, and the optimal conditions were as follows: a temperature of 47.2 °C, a pH of 7.3 and an enzyme concentration of 1100 U/g, which resulted in the maximum DPPH clearance rate of 95.44%. Peptides with a Mw of less than 1 kDa (SNNH-1) were obtained by ultrafiltration, and exhibited good scavenging activity for hydroxyl radicals, ABTS radicals and superoxide anion radicals. Furthermore, SNNH-1 significantly promoted the proliferation of HUVECs, and the protective effect of SNNH-1 against oxidative damage of H2O2-induced HUVECs was investigated. The results indicated that all groups receiving SNNH-1 pretreatment showed an increase in GSH-Px, SOD, and CAT activities compared with the model group. In addition, SNNH-1 pretreatment reduced the levels of ROS and MDA in HUVECs with H2O2-induced oxidative damage. These results indicate that collagen peptides from swim bladders of Nibea japonica can significantly reduce the oxidative stress damage caused by H2O2 in HUVECs and provides a basis for the application of collagen peptides in the food industry, pharmaceuticals, and cosmetics. Full article
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11 pages, 5357 KiB  
Article
Biocompatibility of a Marine Collagen-Based Scaffold In Vitro and In Vivo
by Dafna Benayahu, Leslie Pomeraniec, Shai Shemesh, Snir Heller, Yoav Rosenthal, Lea Rath-Wolfson and Yehuda Benayahu
Mar. Drugs 2020, 18(8), 420; https://doi.org/10.3390/md18080420 - 11 Aug 2020
Cited by 27 | Viewed by 3967
Abstract
Scaffold material is essential in providing mechanical support to tissue, allowing stem cells to improve their function in the healing and repair of trauma sites and tissue regeneration. The scaffold aids cell organization in the damaged tissue. It serves and allows bio mimicking [...] Read more.
Scaffold material is essential in providing mechanical support to tissue, allowing stem cells to improve their function in the healing and repair of trauma sites and tissue regeneration. The scaffold aids cell organization in the damaged tissue. It serves and allows bio mimicking the mechanical and biological properties of the target tissue and facilitates cell proliferation and differentiation at the regeneration site. In this study, the developed and assayed bio-composite made of unique collagen fibers and alginate hydrogel supports the function of cells around the implanted material. We used an in vivo rat model to study the scaffold effects when transplanted subcutaneously and as an augment for tendon repair. Animals’ well-being was measured by their weight and daily activity post scaffold transplantation during their recovery. At the end of the experiment, the bio-composite was histologically examined, and the surrounding tissues around the implant were evaluated for inflammation reaction and scarring tissue. In the histology, the formation of granulation tissue and fibroblasts that were part of the inclusion process of the implanted material were noted. At the transplanted sites, inflammatory cells, such as plasma cells, macrophages, and giant cells, were also observed as expected at this time point post transplantation. This study demonstrated not only the collagen-alginate device biocompatibility, with no cytotoxic effects on the analyzed rats, but also that the 3D structure enables cell migration and new blood vessel formation needed for tissue repair. Overall, the results of the current study proved for the first time that the implantable scaffold for long-term confirms the well-being of these rats and is correspondence to biocompatibility ISO standards and can be further developed for medical devices application. Full article
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17 pages, 2425 KiB  
Article
The Effect of Depth on the Morphology, Bacterial Clearance, and Respiration of the Mediterranean Sponge Chondrosia reniformis (Nardo, 1847)
by Mert Gökalp, Tjitske Kooistra, Miguel Soares Rocha, Tiago H. Silva, Ronald Osinga, AlberTinka J. Murk and Tim Wijgerde
Mar. Drugs 2020, 18(7), 358; https://doi.org/10.3390/md18070358 - 10 Jul 2020
Cited by 23 | Viewed by 4740
Abstract
To support the successful application of sponges for water purification and collagen production, we evaluated the effect of depth on sponge morphology, growth, physiology, and functioning. Specimens of Eastern Mediterranean populations of the sponge Chondrosia reniformis (Nardo, 1847) (Demospongiae, Chondrosiida, Chondrosiidae) were reciprocally [...] Read more.
To support the successful application of sponges for water purification and collagen production, we evaluated the effect of depth on sponge morphology, growth, physiology, and functioning. Specimens of Eastern Mediterranean populations of the sponge Chondrosia reniformis (Nardo, 1847) (Demospongiae, Chondrosiida, Chondrosiidae) were reciprocally transplanted between 5 and 20 m depth within the Kaş-Kekova Marine Reserve Area. Control sponges at 5 m had fewer but larger oscula than their conspecifics at 20 m, and a significant inverse relationship between the osculum density and size was found in C. reniformis specimens growing along a natural depth gradient. Sponges transplanted from 20 to 5 m altered their morphology to match the 5 m control sponges, producing fewer but larger oscula, whereas explants transplanted from 5 to 20 m did not show a reciprocal morphological plasticity. Despite the changes in morphology, the clearance, respiration, and growth rates were comparable among all the experimental groups. This indicates that depth-induced morphological changes do not affect the overall performance of the sponges. Hence, the potential for the growth and bioremediation of C. reniformis in mariculture is not likely to change with varying culture depth. The collagen content, however, was higher in shallow water C. reniformis compared to deeper-growing sponges, which requires further study to optimize collagen production. Full article
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15 pages, 3835 KiB  
Article
Functionalization of 3D Chitinous Skeletal Scaffolds of Sponge Origin Using Silver Nanoparticles and Their Antibacterial Properties
by Tomasz Machałowski, Maria Czajka, Iaroslav Petrenko, Heike Meissner, Christian Schimpf, David Rafaja, Jerzy Ziętek, Beata Dzięgiel, Łukasz Adaszek, Alona Voronkina, Valentin Kovalchuk, Jakub Jaroszewicz, Andriy Fursov, Mehdi Rahimi-Nasrabadi, Dawid Stawski, Nicole Bechmann, Teofil Jesionowski and Hermann Ehrlich
Mar. Drugs 2020, 18(6), 304; https://doi.org/10.3390/md18060304 - 10 Jun 2020
Cited by 13 | Viewed by 3443
Abstract
Chitin, as one of nature’s most abundant structural polysaccharides, possesses worldwide, high industrial potential and a functionality that is topically pertinent. Nowadays, the metallization of naturally predesigned, 3D chitinous scaffolds originating from marine sponges is drawing focused attention. These invertebrates represent a unique, [...] Read more.
Chitin, as one of nature’s most abundant structural polysaccharides, possesses worldwide, high industrial potential and a functionality that is topically pertinent. Nowadays, the metallization of naturally predesigned, 3D chitinous scaffolds originating from marine sponges is drawing focused attention. These invertebrates represent a unique, renewable source of specialized chitin due to their ability to grow under marine farming conditions. In this study, the development of composite material in the form of 3D chitin-based skeletal scaffolds covered with silver nanoparticles (AgNPs) and Ag-bromide is described for the first time. Additionally, the antibacterial properties of the obtained materials and their possible applications as a water filtration system are also investigated. Full article
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20 pages, 9043 KiB  
Article
Electrochemical Approach for Isolation of Chitin from the Skeleton of the Black Coral Cirrhipathes sp. (Antipatharia)
by Krzysztof Nowacki, Izabela Stępniak, Enrico Langer, Mikhail Tsurkan, Marcin Wysokowski, Iaroslav Petrenko, Yuliya Khrunyk, Andriy Fursov, Marzia Bo, Giorgio Bavestrello, Yvonne Joseph and Hermann Ehrlich
Mar. Drugs 2020, 18(6), 297; https://doi.org/10.3390/md18060297 - 2 Jun 2020
Cited by 27 | Viewed by 5492
Abstract
The development of novel and effective methods for the isolation of chitin, which remains one of the fundamental aminopolysaccharides within skeletal structures of diverse marine invertebrates, is still relevant. In contrast to numerous studies on chitin extraction from crustaceans, mollusks and sponges, there [...] Read more.
The development of novel and effective methods for the isolation of chitin, which remains one of the fundamental aminopolysaccharides within skeletal structures of diverse marine invertebrates, is still relevant. In contrast to numerous studies on chitin extraction from crustaceans, mollusks and sponges, there are only a few reports concerning its isolation from corals, and especially black corals (Antipatharia). In this work, we report the stepwise isolation and identification of chitin from Cirrhipathes sp. (Antipatharia, Antipathidae) for the first time. The proposed method, aiming at the extraction of the chitinous scaffold from the skeleton of black coral species, combined a well-known chemical treatment with in situ electrolysis, using a concentrated Na2SO4 aqueous solution as the electrolyte. This novel method allows the isolation of α-chitin in the form of a microporous membrane-like material. Moreover, the extracted chitinous scaffold, with a well-preserved, unique pore distribution, has been extracted in an astoundingly short time (12 h) compared to the earlier reported attempts at chitin isolation from Antipatharia corals. Full article
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15 pages, 18538 KiB  
Article
Pepsin-Soluble Collagen from the Skin of Lophius litulo: A Preliminary Study Evaluating Physicochemical, Antioxidant, and Wound Healing Properties
by Wen Zhang, Jiawen Zheng, Xiaoxiao Tian, Yunping Tang, Guofang Ding, Zuisu Yang and Huoxi Jin
Mar. Drugs 2019, 17(12), 708; https://doi.org/10.3390/md17120708 - 16 Dec 2019
Cited by 21 | Viewed by 4139
Abstract
The structure of pepsin-solubilized collagen (PSC) obtained from the skin of Lophius litulon was analyzed using the sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). SDS-PAGE results showed that PSC from Lophius litulon skin was [...] Read more.
The structure of pepsin-solubilized collagen (PSC) obtained from the skin of Lophius litulon was analyzed using the sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). SDS-PAGE results showed that PSC from Lophius litulon skin was collagen type I and had collagen-specific α1, α2, β, and γ chains. FTIR results indicated that the infrared spectrum of PSC ranged from 400 to 4000 cm−1, with five main amide bands. SEM revealed the microstructure of PSC, which consisted of clear fibrous and porous structures. In vitro antioxidant studies demonstrated that PSC revealed the scavenging ability for 2,2-diphenyl-1-picrylhydrazyl (DPPH), HO·, O2·, and ABTS·. Moreover, animal experiments were conducted to evaluate the biocompatibility of PSC. The collagen sponge group showed a good biocompatibility in the skin wound model and may play a positive role in the progression of the healing process. The cumulative results suggest that collagen from the skin of Lophius litulon has potential applications in wound healing due to its good biocompatibility. Full article
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14 pages, 6776 KiB  
Article
Physicochemical and Biological Properties of Gelatin Extracted from Marine Snail Rapana venosa
by Alexandra Gaspar-Pintiliescu, Laura Mihaela Stefan, Elena Daniela Anton, Daniela Berger, Cristian Matei, Ticuta Negreanu-Pirjol and Lucia Moldovan
Mar. Drugs 2019, 17(10), 589; https://doi.org/10.3390/md17100589 - 17 Oct 2019
Cited by 37 | Viewed by 5562
Abstract
In this study, we aimed to obtain gelatin from the marine snail Rapana venosa using acidic and enzymatic extraction methods and to characterize these natural products for cosmetic and pharmaceutical applications. Marine gelatins presented protein values and hydroxyproline content similar to those of [...] Read more.
In this study, we aimed to obtain gelatin from the marine snail Rapana venosa using acidic and enzymatic extraction methods and to characterize these natural products for cosmetic and pharmaceutical applications. Marine gelatins presented protein values and hydroxyproline content similar to those of commercial mammalian gelatin, but with higher melting temperatures. Their electrophoretic profile and Fourier transform infrared (FTIR) spectra revealed protein and absorption bands situated in the amide region, specific for gelatin molecule. Scanning electron microscopy (SEM) analysis showed significant differences in the structure of the lyophilized samples, depending on the type of gelatin. In vitro studies performed on human keratinocytes showed no cytotoxic effect of acid-extracted gelatin at all tested concentrations and moderate cytotoxicity of enzymatic extracted gelatin at concentrations higher than 0.5 mg/mL. Also, both marine gelatins favored keratinocyte cell adhesion. No irritant potential was recorded as the level of IL-1α and IL-6 proinflammatory cytokines released by HaCaT cells cultivated in the presence of marine gelatins was significantly reduced. Together, these data suggest that marine snails are an alternative source of gelatins with potential use in pharmaceutical and skincare products. Full article
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17 pages, 6514 KiB  
Article
Naturally Drug-Loaded Chitin: Isolation and Applications
by Valentine Kovalchuk, Alona Voronkina, Björn Binnewerg, Mario Schubert, Liubov Muzychka, Marcin Wysokowski, Mikhail V. Tsurkan, Nicole Bechmann, Iaroslav Petrenko, Andriy Fursov, Rajko Martinovic, Viatcheslav N. Ivanenko, Jane Fromont, Oleg B. Smolii, Yvonne Joseph, Marco Giovine, Dirk Erpenbeck, Michael Gelinsky, Armin Springer, Kaomei Guan, Stefan R. Bornstein and Hermann Ehrlichadd Show full author list remove Hide full author list
Mar. Drugs 2019, 17(10), 574; https://doi.org/10.3390/md17100574 - 10 Oct 2019
Cited by 47 | Viewed by 5443
Abstract
Naturally occurring three-dimensional (3D) biopolymer-based matrices that can be used in different biomedical applications are sustainable alternatives to various artificial 3D materials. For this purpose, chitin-based structures from marine sponges are very promising substitutes. Marine sponges from the order Verongiida (class Demospongiae) are [...] Read more.
Naturally occurring three-dimensional (3D) biopolymer-based matrices that can be used in different biomedical applications are sustainable alternatives to various artificial 3D materials. For this purpose, chitin-based structures from marine sponges are very promising substitutes. Marine sponges from the order Verongiida (class Demospongiae) are typical examples of demosponges with well-developed chitinous skeletons. In particular, species belonging to the family Ianthellidae possess chitinous, flat, fan-like fibrous skeletons with a unique, microporous 3D architecture that makes them particularly interesting for applications. In this work, we focus our attention on the demosponge Ianthella flabelliformis (Linnaeus, 1759) for simultaneous extraction of both naturally occurring (“ready-to-use”) chitin scaffolds, and biologically active bromotyrosines which are recognized as potential antibiotic, antitumor, and marine antifouling substances. We show that selected bromotyrosines are located within pigmental cells which, however, are localized within chitinous skeletal fibers of I. flabelliformis. A two-step reaction provides two products: treatment with methanol extracts the bromotyrosine compounds bastadin 25 and araplysillin-I N20 sulfamate, and a subsequent treatment with acetic acid and sodium hydroxide exposes the 3D chitinous scaffold. This scaffold is a mesh-like structure, which retains its capillary network, and its use as a potential drug delivery biomaterial was examined for the first time. The results demonstrate that sponge-derived chitin scaffolds, impregnated with decamethoxine, effectively inhibit growth of the human pathogen Staphylococcus aureus in an agar diffusion assay. Full article
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19 pages, 3678 KiB  
Article
Physicochemical and Functional Properties of Type I Collagens in Red Stingray (Dasyatis akajei) Skin
by Junde Chen, Jianying Li, Zhongbao Li, Ruizao Yi, Shenjia Shi, Kunyuan Wu, Yushuang Li and Sijia Wu
Mar. Drugs 2019, 17(10), 558; https://doi.org/10.3390/md17100558 - 28 Sep 2019
Cited by 43 | Viewed by 4311
Abstract
Collagen is widely used in the pharmaceutical, tissue engineering, nutraceutical, and cosmetic industries. In this study, acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) were extracted from the skin of red stingray, and its physicochemical and functional properties were investigated. The yields of ASC [...] Read more.
Collagen is widely used in the pharmaceutical, tissue engineering, nutraceutical, and cosmetic industries. In this study, acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) were extracted from the skin of red stingray, and its physicochemical and functional properties were investigated. The yields of ASC and PSC were 33.95 ± 0.7% and 37.18 ± 0.71% (on a dry weight basis), respectively. ASC and PSC were identified as type I collagen by Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE) analysis, possessing a complete triple helix structure as determined by UV absorption, Fourier transform infrared, circular dichroism, and X-ray diffraction spectroscopy. Contact angle experiments indicated that PSC was more hydrophobic than ASC. Thermal stability tests revealed that the melting temperature of PSC from red stingray skin was higher than that of PSC from duck skin, and the difference in the melting temperature between these two PSCs was 9.24 °C. Additionally, both ASC and PSC were functionally superior to some other proteins from terrestrial sources, such as scallop gonad protein, whey protein, and goose liver protein. These results suggest that PSC from red stingray skin could be used instead of terrestrial animal collagen in drugs, foods, cosmetics, and biological functional materials, and as scaffolds for bone regeneration. Full article
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12 pages, 6876 KiB  
Article
Enantioselective Hydrolysis of Styrene Oxide and Benzyl Glycidyl Ether by a Variant of Epoxide Hydrolase from Agromyces mediolanus
by Huoxi Jin, Yan Li, Qianwei Zhang, Saijun Lin, Zuisu Yang and Guofang Ding
Mar. Drugs 2019, 17(6), 367; https://doi.org/10.3390/md17060367 - 20 Jun 2019
Cited by 2 | Viewed by 3541
Abstract
Enantiopure epoxides are versatile synthetic intermediates for producing optically active pharmaceuticals. In an effort to provide more options for the preparation of enantiopure epoxides, a variant of the epoxide hydrolase (vEH-Am) gene from a marine microorganism Agromyces mediolanus was synthesized and expressed in [...] Read more.
Enantiopure epoxides are versatile synthetic intermediates for producing optically active pharmaceuticals. In an effort to provide more options for the preparation of enantiopure epoxides, a variant of the epoxide hydrolase (vEH-Am) gene from a marine microorganism Agromyces mediolanus was synthesized and expressed in Escherichia coli. Recombiant vEH-Am displayed a molecular weight of 43 kDa and showed high stability with a half-life of 51.1 h at 30 °C. The purified vEH-Am exhibited high enantioselectivity towards styrene oxide (SO) and benzyl glycidyl ether (BGE). The vEH-Am preferentially converted (S)-SO, leaving (R)-SO with the enantiomeric excess (ee) >99%. However, (R)-BGE was preferentially hydrolyzed by vEH-Am, resulting in (S)-BGE with >99% ee. To investigate the origin of regioselectivity, the interactions between vEH-Am and enantiomers of SO and BGE were analyzed by molecular docking simulation. In addition, it was observed that the yields of (R)-SO and (S)-BGE decreased with the increase of substrate concentrations. The yield of (R)-SO was significantly increased by adding 2% (v/v) Tween-20 or intermittent supplementation of the substrate. To our knowledge, vEH-Am displayed the highest enantioselectivity for the kinetic resolution of racemic BGE among the known EHs, suggesting promising applications of vEH-Am in the preparation of optically active BGE. Full article
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12 pages, 5185 KiB  
Article
Serine Protease from Nereis virens Inhibits H1299 Lung Cancer Cell Proliferation via the PI3K/AKT/mTOR Pathway
by Yanan Chen, Yunping Tang, Yanhua Tang, Zuisu Yang and Guofang Ding
Mar. Drugs 2019, 17(6), 366; https://doi.org/10.3390/md17060366 - 20 Jun 2019
Cited by 12 | Viewed by 3820
Abstract
This study explores the in vitro anti-proliferative mechanism between Nereis Active Protease (NAP) and human lung cancer H1299 cells. Colony formation and migration of cells were significantly lowered, following NAP treatment. Flow cytometry results suggested that NAP-induced growth inhibition of H1299 cells is [...] Read more.
This study explores the in vitro anti-proliferative mechanism between Nereis Active Protease (NAP) and human lung cancer H1299 cells. Colony formation and migration of cells were significantly lowered, following NAP treatment. Flow cytometry results suggested that NAP-induced growth inhibition of H1299 cells is linked to apoptosis, and that NAP can arrest the cells at the G0/G1 phase. The ERK/MAPK and PI3K/AKT/mTOR pathways were selected for their RNA transcripts, and their roles in the anti-proliferative mechanism of NAP were studied using Western blots. Our results suggested that NAP led to the downregulation of p-ERK (Thr 202/Tyr 204), p-AKT (Ser 473), p-PI3K (p85), and p-mTOR (Ser 2448), suggesting that NAP-induced H1299 cell apoptosis occurs via the PI3K/AKT/mTOR pathway. Furthermore, specific inhibitors LY294002 and PD98059 were used to inhibit these two pathways. The effect of NAP on the downregulation of p-ERK and p-AKT was enhanced by the LY294002 (a PI3K inhibitor), while the inhibitor PD98059 had no obvious effect. Overall, the results suggested that NAP exhibits antiproliferative activity by inducing apoptosis, through the inhibition of the PI3K/AKT/mTOR pathway. Full article
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17 pages, 3564 KiB  
Article
Four Antioxidant Peptides from Protein Hydrolysate of Red Stingray (Dasyatis akajei) Cartilages: Isolation, Identification, and In Vitro Activity Evaluation
by Xiao-Yang Pan, Yu-Mei Wang, Li Li, Chang-Feng Chi and Bin Wang
Mar. Drugs 2019, 17(5), 263; https://doi.org/10.3390/md17050263 - 3 May 2019
Cited by 44 | Viewed by 3526
Abstract
In the work, water-soluble proteins of red stingray (Dasyatis akajei) cartilages were extracted by guanidine hydrochloride and hydrolyzed using trypsin. Subsequently, four antioxidant peptides (RSHP-A, RSHP-B, RSHP-C, and RSHP-D) were isolated from the water-soluble protein hydrolysate while using ultrafiltration and chromatographic [...] Read more.
In the work, water-soluble proteins of red stingray (Dasyatis akajei) cartilages were extracted by guanidine hydrochloride and hydrolyzed using trypsin. Subsequently, four antioxidant peptides (RSHP-A, RSHP-B, RSHP-C, and RSHP-D) were isolated from the water-soluble protein hydrolysate while using ultrafiltration and chromatographic techniques, and the amino acid sequences of RSHP-A, RSHP-B, RSHP-C, and RSHP-D were identified as Val-Pro-Arg (VPR), Ile-Glu-Pro-His (IEPH), Leu-Glu-Glu--Glu-Glu (LEEEE), and Ile-Glu-Glu-Glu-Gln (IEEEQ), with molecular weights of 370.46 Da, 494.55 Da, 647.64 Da, and 646.66 Da, respectively. VPR, IEPH, LEEEE, and IEEEQ exhibited good scavenging activities on the DPPH radical (EC50 values of 4.61, 1.90, 3.69, and 4.01 mg/mL, respectively), hydroxyl radical (EC50 values of 0.77, 0.46, 0.70, and 1.30 mg/mL, respectively), superoxide anion radical (EC50 values of 0.08, 0.17, 0.15, and 0.16 mg/mL, respectively), and ABTS cation radical (EC50 values of 0.15, 0.11, 0.19, and 0.18 mg/mL, respectively). Among the four isolated antioxidant peptides, IEPH showed the strongest reducing power and lipid peroxidation inhibition activity, but LEEEE showed the highest Fe2+-chelating ability. The present results suggested that VPR, IEPH, LEEEE, and IEEEQ might have the possibility of being an antioxidant additive that is used in functional food and pharmaceuticals. Full article
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12 pages, 3539 KiB  
Article
Collagen Extracted from Bigeye Tuna (Thunnus obesus) Skin by Isoelectric Precipitation: Physicochemical Properties, Proliferation, and Migration Activities
by Xinhui Lin, Yinyue Chen, Huoxi Jin, Qiaoling Zhao, Chenjuan Liu, Renwei Li, Fangmiao Yu, Yan Chen, Fangfang Huang, Zuisu Yang, Guofang Ding and Yunping Tang
Mar. Drugs 2019, 17(5), 261; https://doi.org/10.3390/md17050261 - 1 May 2019
Cited by 28 | Viewed by 4966
Abstract
Collagen was extracted from bigeye tuna (Thunnus obesus) skins by salting-out (PSC-SO) and isoelectric precipitation (PSC-IP) methods. The yield of the PSC-IP product was approximately 17.17% (dry weight), which was greater than the yield obtained from PSC-SO (14.14% dry weight). Sodium [...] Read more.
Collagen was extracted from bigeye tuna (Thunnus obesus) skins by salting-out (PSC-SO) and isoelectric precipitation (PSC-IP) methods. The yield of the PSC-IP product was approximately 17.17% (dry weight), which was greater than the yield obtained from PSC-SO (14.14% dry weight). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis indicated that collagen from bigeye tuna skin belongs to collagen type I. Inductively coupled plasma mass spectrometry results indicate that the heavy metal abundance in PSC-IP was lower than the maximum acceptable amounts according to Chinese regulatory standards. In addition, results from a methylthiazolyldiphenyl-tetrazolium bromide assay and an in vitro scratch assay demonstrated that PSC-IP could promote the proliferation and migration of NIH-3T3 fibroblasts. Overall, results suggest PSC-IP could be used to rapidly extract collagen from marine by-products instead of traditional salting-out methods. Collagen from bigeye tuna skin may also have strong potential for cosmetic and biomedical applications. Full article
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