Effects of fish collagen peptides on collagen post-translational modifications and mineralization in an osteoblastic cell culture system

Cellular Senescence and Inflammaging in the Bone: Pathways, Genetics, Anti-Aging Strategies and Interventions

Advancing age is associated with several age-related diseases (ARDs), with musculoskeletal conditions impacting millions of elderly people worldwide. With orthopedic conditions contributing towards considerable number of patients, a deeper understanding of bone aging is the need of the hour. One of the underlying factors of bone aging is cellular senescence and its associated senescence associated secretory phenotype (SASP). SASP comprises of pro-inflammatory markers, cytokines and chemokines that arrest cell growth and development. The accumulation of SASP over several years leads to chronic low-grade inflammation with advancing age, also known as inflammaging. The pathways and molecular mechanisms focused on bone senescence and inflammaging are currently limited but are increasingly being explored. Most of the genes, pathways and mechanisms involved in senescence and inflammaging coincide with those associated with cancer and other ARDs like osteoarthritis (OA). Thus, exploring these pathways using techniques like sequencing, identifying these factors and combatting them with the most suitable approach are crucial for healthy aging and the early detection of ARDs. Several approaches can be used to aid regeneration and reduce senescence in the bone. These may be pharmacological, non-pharmacological and lifestyle interventions. With increasing evidence towards the intricate relationship between aging, senescence, inflammation and ARDs, these approaches may also be used as anti-aging strategies for the aging bone marrow (BM).

Unlocking the Therapeutic Potential of Marine Collagen: A Scientific Exploration for Delaying Skin Aging

Aging is closely associated with collagen degradation, impacting the structure and strength of the muscles, joints, bones, and skin. The continuous aging of the skin is a natural process that is influenced by extrinsic factors such as UV exposure, dietary patterns, smoking habits, and cosmetic supplements. Supplements that contain collagen can act as remedies that help restore vitality and youth to the skin, helping combat aging. Notably, collagen supplements enriched with essential amino acids such as proline and glycine, along with marine fish collagen, have become popular for their safety and effectiveness in mitigating the aging process. To compile the relevant literature on the anti-aging applications of marine collagen, a search and analysis of peer-reviewed papers was conducted using PubMed, Cochrane Library, Web of Science, and Embase, covering publications from 1991 to 2024. From in vitro to in vivo experiments, the reviewed studies elucidate the anti-aging benefits of marine collagen, emphasizing its role in combating skin aging by minimizing oxidative stress, photodamage, and the appearance of wrinkles. Various bioactive marine peptides exhibit diverse anti-aging properties, including free radical scavenging, apoptosis inhibition, lifespan extension in various organisms, and protective effects in aging humans. Furthermore, the topical application of hyaluronic acid is discussed as a mechanism to increase collagen production and skin moisture, contributing to the anti-aging effects of collagen supplementation. The integration of bio-tissue engineering in marine collagen applications is also explored, highlighting its proven utility in skin healing and bone regeneration applications. However, limitations to the scope of its application exist. Thus, by delving into these nuanced considerations, this review contributes to a comprehensive understanding of the potential and challenges associated with marine collagen in the realm of anti-aging applications.

Partly Substituting Whey for Collagen Peptide Supplementation Improves Neither Indices of Muscle Damage Nor Recovery of Functional Capacity During Eccentric Exercise Training in Fit Males

Previous studies showed that collagen peptide supplementation along with resistance exercise enhance muscular recovery and function. Yet, the efficacy of collagen peptide supplementation in addition to standard nutritional practices in athletes remains unclear. Therefore, the objective of the study was to compare the effects of combined collagen peptide (20 g) and whey protein (25 g) supplementation with a similar daily protein dose (45 g) of whey protein alone on indices of muscle damage and recovery of muscular performance during eccentric exercise training. Young fit males participated in a 3-week training period involving unilateral eccentric exercises for the knee extensors. According to a double-blind, randomized, parallel-group design, before and after training, they received either whey protein (n = 11) or whey protein + collagen peptides (n = 11). Forty-eight hours after the first training session, maximal voluntary isometric and dynamic contraction of the knee extensors were transiently impaired by ∼10% (Ptime < .001) in whey protein and whey protein + collagen peptides, while creatine kinase levels were doubled in both groups (Ptime < .01). Furthermore, the training intervention improved countermovement jump performance and maximal voluntary dynamic contraction by respectively 8% and 10% (Ptime < .01) and increased serum procollagen type 1N-terminal peptide concentration by 10% (Ptime < .01). However, no differences were found for any of the outcomes between whey and whey protein + collagen peptides. In conclusion, substituting a portion of whey protein for collagen peptide, within a similar total protein dose, improved neither indices of eccentric muscle damage nor functional outcomes during eccentric training.

Hydrolyzed Collagen Tripeptide Promotes Longitudinal Bone Growth in Childhood Rats via Increases in Insulin-Like Growth Factor-1 and Bone Morphogenetic Proteins

Previous studies have reported that collagen tripeptide (CTP) derived from collagen hydrolysate has various beneficial effects on health by protecting against skin aging and improving bone formation and cartilage regeneration. Collagen-Tripep20TM (CTP20), which is a low-molecular-weight CTP derived from fish skin, contains a bioactive CTP, Gly-Pro-Hyp >3.2% with a tripeptide content >20%. Herein, we investigated the osteogenic effects and mechanisms of CTP20 (<500 Da) on MG-63 osteoblast-like cells and SW1353 chondrocytes. And we measured promoting ratio of the longitudinal bone growth in childhood rats. First, CTP20 at 100 μg/mL elevated the proliferation (15.0% and 28.2%), alkaline phosphatase activity (29.3% and 32.0%), collagen synthesis (1.25- and 1.14-fold), and calcium deposition (1.18- and 1.15-fold) in MG-63 cells and SW1353, respectively. In addition, we found that CTP20 could promote the longitudinal growth and height of the growth plate of the tibia in childhood rats. CTP20 enhanced the protein expression of insulin-like growth factor-1 (IGF-1) in MG-63 and SW1353 cells, and in the growth plate of childhood rats, along with Janus Kinase 2, and signal transducer and activator of transcription 5 activation in MG-63 and SW1353 cells. CTP20 also elevated the expression levels of bone morphogenetic proteins (BMPs) in MG-63 and SW1353 cells and in the growth plates of childhood rats. These results indicate that CTP20 may promote the endochondral ossification and longitudinal bone growth, through enhancing of IGF-1 and BMPs. (Clinical Trial Registration number: smecae 19-09-01).

Challenges and strategies for collagen delivery for tissue regeneration

Background: Aged skin is characterized by wrinkles, hyperpigmentation, and roughness. Collagen is the most abundant protein in our body and it’s responsible for skin health and it’s mostly influenced by factors that accelerated aging such as UV. Objective: This study aimed to identify the potential use of collagen as skin supplementation and the challenges and strategies for its delivery. Methods: The articles were first searched through the existing database with the keyword of “collagen antiaging”. The 585 articles were then screened by year of publication (2012-2022) resulted in 475 articles. The articles were then selected based on the delivery of collagen either orally or topically, resulted in 12 articles for further analysis. Results: Collagen has important roles in skin physiology by involving some mechanisms through inhibition of Mitogen-Activated Protein Kinase, induction of Tissue Growth Factor β (TGF-β), and inhibition of Nuclear Factor kappa beta (NF-κβ). The oral administration of collagen has an effective biological activity but requires large doses (up to 5 g daily). Meanwhile, the topical administration of collagen is limited by poor permeability due to high molecular weight (±300 kDa). Several strategies need to be carried out mainly by physical modification such as hydrolyzed collagen or entrapment of collagen using a suitable delivery system. Conclusions: Collagen could improve the skin properties, but further research should be conducted to increase its penetration either by physical modification or entrapment into suitable carrier.

Characteristics and osteogenic mechanism of glycosylated peptides-calcium chelate

Finding effective practical components to promote bone mineralization from the diet has become an effective method to regulate bone mass. In this study, peptides-calcium chelate derived from Crimson Snapper scales protein hydrolysates (CSPHs), and xylooligosaccharide (XOS)-peptides-calcium chelate prepared by transglutaminase (TGase) pathway, named CSPHs-Ca and XOS-CSPHs-Ca-TG, were used to explore the effects of glycosylation on their structural properties and osteogenic activity in vitro. Results showed that XOS-CSPHs-Ca-TG had better calcium phosphate crystallization inhibition activity with more unified structures than CSPHs-Ca, and could effectively maintain a stable calcium content in the gastrointestinal tract. Meanwhile, the glycosylated peptide-calcium chelate could accelerate the calcium transport efficiency in the Caco-2 cell monolayer, up to 3.54 folds of the control group. Moreover, XOS-CSPHs-Ca-TG exhibited prominent osteogenic effects by promoting the proliferation of MC3T3-E1 cells, increasing the secretion of osteogenic related factors, and accelerating the formation of intracellular mineralized nodules. RT-qPCR results further confirmed that this beneficial effect of XOS-CSPHs-Ca-TG was achieved by activating the Wnt/β-catenin signaling pathway. These results suggested that glycosylation might be a promising method for optimizing structural properties and osteogenic activity of peptide-calcium chelate.

Tilapia skin peptides restore cyclophosphamide-induced premature ovarian failure via inhibiting oxidative stress and apoptosis in mice

Tilapia (Oreochromis mossambicus) skin high value-added compounds have not been fully utilized in tilapia processing. Here, the protective effects of tilapia skin peptides (TSP) on primary ovarian failure (POF) and their underlying mechanisms in mice were investigated. Cyclophosphamide (CP) was injected intraperitoneally (ip) for 14 days (10 mg kg^-1 d^-1) to establish a mouse model of POF. At the same time, the mice were given intragastrically (ig) TSP for 30 days (250 mg kg^-1 d^-1, 500 mg kg^-1 d^-1, and 1000 mg kg^-1 d^-1, respectively). The ovarian index, estrous cycle, hormone level, changes in the number of follicles at various levels, and biochemical tests were carried out at the end of the experiment. The body weight and ovarian index of mice in the POF group were markedly lower than that of the control group. Treatment with TSP reversed these changes significantly. TSP administration significantly restored the estrous cycle disorder of the mice versus that of the POF group. The level changes of progesterone (P), estradiol (E2), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) induced by CP were significantly reversed by TSP treatment. TSP inhibited oxidative stress in CP-induced mice by enhancing the total superoxide dismutase (T-SOD) activity and reducing malondialdehyde (MDA) levels in the ovaries. TSP improved the apoptosis of ovarian granulosa cells in CP-induced mice compared with the POF group. Furthermore, TSP regulated the Bcl-2/Bax/caspase-3 apoptosis pathway and enhanced the Nrf2/HO-1 signaling pathway. In conclusion, TSP could improve CP-induced POF via alleviating ovarian oxidative stress and granulosa cell apoptosis.

Marine Collagen: A Promising Biomaterial for Wound Healing, Skin Anti-Aging, and Bone Regeneration

Marine organisms harbor numerous bioactive substances that can be utilized in the pharmaceutical and cosmetic industries. Scientific research on various applications of collagen extracted from these organisms has become increasingly prevalent. Marine collagen can be used as a biomaterial because it is water soluble, metabolically compatible, and highly accessible. Upon review of the literature, it is evident that marine collagen is a versatile compound capable of healing skin injuries of varying severity, as well as delaying the natural human aging process. From in vitro to in vivo experiments, collagen has demonstrated its ability to invoke keratinocyte and fibroblast migration as well as vascularization of the skin. Additionally, marine collagen and derivatives have proven beneficial and useful for both osteoporosis and osteoarthritis prevention and treatment. Other bone-related diseases may also be targeted by collagen, as it is capable of increasing bone mineral density, mineral deposition, and importantly, osteoblast maturation and proliferation. In this review, we demonstrate the advantages of marine collagen over land animal sources and the biomedical applications of marine collagen related to bone and skin damage. Finally, some limitations of marine collagen are briefly discussed.

Measuring the oral bioavailability of protein hydrolysates derived from food sources: A critical review of current bioassays

BACKGROUND

Food proteins are a source of hydrolysates with potentially useful biological attributes. Bioactive peptides from food-derived proteins are released from hydrolysates using exogenous industrial processes or endogenous intestinal enzymes. Current in vitro permeability assays have limitations in predicting the oral bioavailability (BA) of bioactive peptides in humans. There are also difficulties in relating the low blood levels of food-derived bioactive peptides detected in preclinical in vivo models to pharmacodynamic read-outs relevant for humans.

SCOPE AND APPROACH

In this review, we describe in vitro assays of digestion, permeation, and metabolism as indirect predictors of the potential oral BA of hydrolysates and their constituent bioactive peptides. We discuss the relationship between industrial hydrolysis processes and the oral BA of hydrolysates and their peptide by-products.

KEY FINDINGS

Hydrolysates are challenging for analytical detection methods due to capacity for enzymatic generation of peptides with novel sequences and also new modifications of these peptides during digestion. Mass spectrometry and peptidomics can improve the capacity to detect individual peptides released from complex hydrolysates in biological milieu.

Marine-Derived Collagen as Biomaterials for Human Health

Collagen is a kind of biocompatible protein material, which is widely used in medical tissue engineering, drug delivery, cosmetics, food and other fields. Because of its wide source, low extraction cost and good physical and chemical properties, it has attracted the attention of many researchers in recent years. However, the application of collagen derived from terrestrial organisms is limited due to the existence of diseases, religious beliefs and other problems. Therefore, exploring a wider range of sources of collagen has become one of the main topics for researchers. Marine-derived collagen (MDC) stands out because it comes from a variety of sources and avoids issues such as religion. On the one hand, this paper summarized the sources, extraction methods and characteristics of MDC, and on the other hand, it summarized the application of MDC in the above fields. And on the basis of the review, we found that MDC can not only be extracted from marine organisms, but also from the wastes of some marine organisms, such as fish scales. This makes further use of seafood resources and increases the application prospect of MDC.

Functional roles of fish collagen peptides on bone regeneration

Fish collagen peptides (FCP) derived from the skin, bones and scales are commercially used as a functional food or dietary supplement for hypertension and diabetes. However, there is limited evidence on the effects of FCP on the osteoblast function in contrast to evidence of the effects on wound healing, diabetes and bone regeneration, which have been obtained from animal studies. In this narrative review, we expound on the availability of FCP by basic research using osteoblasts. Low-concentration FCP upregulates the expression of osteoblast proliferation, differentiation and collagen modifying enzyme-related genes. Furthermore, it could accelerate matrix mineralization. FCP may have potential utility as a biomaterial to improve collagen quality and promote mineralization through the mitogen-activated protein kinase and Smad cascades. However, there are few clinical studies on bone regeneration in human subjects. It is desirable to be applied clinically through clinical study as soon as possible, based on the results from basic research.

Diverse and Productive Source of Biopolymer Inspiration: Marine Collagens

Marine biodiversity is expressed through the huge variety of vertebrate and invertebrate species inhabiting intertidal to deep-sea environments. The extraordinary variety of "forms and functions" exhibited by marine animals suggests they are a promising source of bioactive molecules and provides potential inspiration for different biomimetic approaches. This diversity is familiar to biologists and has led to intensive investigation of metabolites, polysaccharides, and other compounds. However, marine collagens are less well-known. This review will provide detailed insight into the diversity of collagens present in marine species in terms of their genetics, structure, properties, and physiology. In the last part of the review the focus will be on the most common marine collagen sources and on the latest advances in the development of innovative materials exploiting, or inspired by, marine collagens.

Applications of marine collagens in bone tissue engineering

For decades, collagen has been among the most widely used biomaterials with several biomedical applications. Recently, researchers have shown a keen interest in collagen obtained from marine sources because of its biocompatibility, biodegradability, ease of extractability, safety, low immunogenicity, and low production costs. A wide variety of marine collagen-based scaffolds have been developed for bone tissue engineering, and these scaffolds display excellent biological effects. This review aims to provide an overview of the biological effects of marine collagen in bone engineering, such as promoting osteogenesis and collagen synthesis, inhibiting inflammation, inducing the differentiation of cartilage, and improving bone mineral density. Marine collagen holds great promise as a biomaterial in bone tissue engineering.

Recent advances in seafood bioactive peptides and their potential for managing osteoporosis

Marine biodiversity provides a range of diverse biological resources, including seafoods that are rich in protein and a well-balanced amino acid composition. Previous studies have shown that peptides can improve bone formation and/or inhibit bone resorption, suggesting the potential for seafood bioactive peptides (SBPs) in development of food and pharmaceuticals for management of osteoporosis. In this review, we provided an up-to-date overview of the anti-osteoporosis activity of SBPs and describe their underlying molecular mechanisms. We focus on SBPs' development, broadening the scope and depth of research, as well as strengthening in vivo and clinical research. In vitro cell cultures and in vivo animal osteoporosis models have demonstrated the potential for seafood-derived SBPs, including fish, mollusks, crustaceans, seaweed and microalgae, in preventing osteoporosis. These peptides may act by activating the signaling pathways, such as BMP/Smads, MAPK, OPG/RANKL/RANK, and NF-κB, which are associated with modulation bone health.

Electrospun nanofibrous membrane of fish collagen/polycaprolactone for cartilage regeneration

Tissue engineering technology provides a promising approach for cartilage repair, and in this strategy, scaffolds play a pivotal role in directing cartilage regeneration. Fish collagen (FC) is currently considered an alternative source of mammalian collagen (MC) for tissue engineering due to its excellent biocompatibility, suitable biodegradability, inert immunogenicity, rich sources, low price and lack of risk for the transmission of zoonosis. Here, we fabricated three types of electrospun nanofibrous membranes composed of FC and polycaprolactone (PCL) with three different FC/PCL ratios (9/1, 7/3, 5/5) and investigated the feasibility of using the membranes with chondrocytes in cartilage regeneration. Our results demonstrated that increases in the FC content were associated with improvements in biodegradability, absorption, and cell adhesion capacity, but weaker mechanical properties. In addition, all three nanofibrous membranes showed satisfactory biocompatibility as evidenced by supporting chondrocyte proliferation and cartilage formation in vitro. Furthermore, all three membranes seeded with chondrocytes formed mature cartilage-like tissue after 8 weeks of in vivo culture, but satisfactory homogeneous cartilage regeneration was only achieved with the F9P1 group. The current results demonstrated that the electrospun FC/PCL membrane is a promising scaffold for cartilage regeneration and that the F9P1 group might represent a relatively suitable ratio. The research models established in the current study provide detailed information for the regeneration of cartilage and other tissue based on electrospun FC/PCL membranes.

Bone-strengthening effects and safety of compound peptides from skin of Chiloscyllium plagiosum and Mustelus griseus

Fish processing produces a lot of by‐products highly containing large amount of proteins which mainly consist of collagen, implying great potential value for application as nutraceutical ingredients. In present study, two kinds of sharks, Chiloscyllium plagiosum and Mustelus griseus, were used as raw material to gain three kinds of “compound peptides” (CPs) by enzymolysis, FCP (CPs from the flesh of C. plagiosum), SCP (CPs from the skin of C. plagiosum), and SMG (CPs from the skin of M. griseus). According to a series of constituent analysis, the molecule weights of FCP, SCP, and SMG were under 800 Da; amino acids composition analysis of FCP, SCP, and SMG showed that there were high glycine, proline, and hydroxyproline and low cysteine contents in SCP and SMG, which is the characteristic of collagen peptides; their total protein contents were 87.500%, 91.875%, and 95.625%, respectively; and heavy metal contents of CPs were all beneath national standards. After three kinds of CPs were administrated intragastrically to C57BL/6 mice at a total dosage of 15 g/kg, bone‐strengthening effects of SCP and SMG were manifested by osteoblasts activity promotion, bone mineral density (BMD) increase, and marrow adipocyte number decrease, yet nonsignificant effects were shown in FCP group. No index showed toxicity of SCP and SMG in subacute toxicology trial, indicating their safety as functional foods. Herein, industrial application foundation of the skins from these two sharks was explored but more efforts should subsequently be implemented for further exploitation.

Marine Collagen as A Promising Biomaterial for Biomedical Applications

This review focuses on the expanding role of marine collagen (MC)-based scaffolds for biomedical applications. A scaffold-a three-dimensional (3D) structure fabricated from biomaterials-is a key supporting element for cell attachment, growth, and maintenance in 3D cell culture and tissue engineering. The mechanical and biological properties of the scaffolds influence cell morphology, behavior, and function. MC, collagen derived from marine organisms, offers advantages over mammalian collagen due to its biocompatibility, biodegradability, easy extractability, water solubility, safety, low immunogenicity, and low production costs. In recent years, the use of MC as an increasingly valuable scaffold biomaterial has drawn considerable attention from biomedical researchers. The characteristics, isolation, physical, and biochemical properties of MC are discussed as an understanding of MC in optimizing the subsequent modification and the chemistries behind important tissue engineering applications. The latest technologies behind scaffold processing are assessed and the biomedical applications of MC and MC-based scaffolds, including tissue engineering and regeneration, wound dressing, drug delivery, and therapeutic approach for diseases, especially those associated with metabolic disturbances such as obesity and diabetes, are discussed. Despite all the challenges, MC holds great promise as a biomaterial for developing medical products and therapeutics.

Human Enriched Serum Following Hydrolysed Collagen Absorption Modulates Bone Cell Activity: from Bedside to Bench and Vice Versa

Collagen proteins are crucial components of the bone matrix. Since collagen-derived products are widely used in the food and supplement industry, one may raise the question whether collagen-enriched diets can provide benefits for the skeleton. In this study, we designed an innovative approach to investigate this question taking into account the metabolites that are formed by the digestive tract and appear in the circulation after ingestion of hydrolysed collagen. Blood samples collected in clinical and pre-clinical trials following ingestion and absorption of hydrolysed collagen were processed and applied on bone-related primary cell cultures. This original ex vivo methodology revealed that hydrolysed collagen-enriched serum had a direct impact on the behaviour of cells from both human and mouse origin that was not observed with controls (bovine serum albumin or hydrolysed casein-enriched serum). These ex vivo findings were fully in line with in vivo results obtained from a mouse model of post-menopausal osteoporosis. A significant reduction of bone loss was observed in mice supplemented with hydrolysed collagen compared to a control protein. Both the modulation of osteoblast and osteoclast activity observed upon incubation with human or mouse serum ex vivo and the attenuation of bone loss in vivo, clearly indicates that the benefits of hydrolysed collagen for osteoporosis prevention go beyond the effect of a simple protein supplementation.

Effect of high-fat, standard, and functional food meals on esophageal and gastric pH in patients with gastroesophageal reflux disease and healthy subjects

OBJECTIVES

To investigate the effects of different test meals on esophageal and intragastric pH in patients with gastroesophageal reflux disease (GERD) and healthy subjects and to demonstrate the relationship between esophageal acid exposure (EAE) and gastric pH.

METHODS

We enrolled patients with reflux esophagitis (RE; n = 15), nonerosive reflux disease (NERD; n = 12) and healthy subjects (n = 10). Four pH electrodes were used to monitor the pH of the distal esophagus, upper border of the lower esophageal sphincter, gastric fundus, and gastric body for 26 hours. Isocaloric and isovolumetric high-fat, standard, and functional meals were supplied randomly to the participants. The EAE and gastric acidity of each meal in fasting and postprandial states were compared.

RESULTS

High-fat meals significantly increased postprandial EAE in patients with RE and NERD. EAE was higher after a high-fat meal than after a standard or functional food meals at the fourth hour postprandially in patients with RE (P < 0.05). Patients with NERD reported fewer symptoms after a functional food meal than after high-fat and standard meals (0 [interquartile range {IQR} 0-1] vs 1 [IQR 0-2] vs 3 [IQR 1-4], P = 0.014). Compared with high-fat and standard meals, functional food meal significantly decreased gastric acidity in patients with RE. EAE was significantly related to gastric acidity in patients with RE.

CONCLUSIONS

High-fat meals increased EAE in patients with RE and NERD. Functional food could serve as adjuvant therapy in GERD patients. EAE was related to gastric acidity in RE patients.

Effect of Collagen Hydrolysates from Silver Carp Skin (Hypophthalmichthys molitrix) on Osteoporosis in Chronologically Aged Mice: Increasing Bone Remodeling

Osteoporosis is a common skeletal disorder in humans and gelatin hydrolysates from mammals have been reported to improve osteoporosis. In this study, 13-month-old mice were used to evaluate the effects of collagen hydrolysates (CHs) from silver carp skin on osteoporosis. No significant differences were observed in mice body weight, spleen or thymus indices after daily intake of antioxidant collagen hydrolysates (ACH; 200 mg/kg body weight (bw) (LACH), 400 mg/kg bw (MACH), 800 mg/kg bw (HACH)), collagenase hydrolyzed collagen hydrolysates (CCH) or proline (400 mg/kg body weight) for eight weeks, respectively. ACH tended to improve bone mineral density, increase bone hydroxyproline content, enhance alkaline phosphatase (ALP) level and reduce tartrate-resistant acid phosphatase 5b (TRAP-5b) activity in serum, with significant differences observed between the MACH and model groups (p < 0.05). ACH exerted a better effect on osteoporosis than CCH at the identical dose, whereas proline had no significant effect on repairing osteoporosis compared to the model group. Western blotting results demonstrated that CHs mainly increased bone remodeling by stimulating the transforming growth factor β1 (TGF-β1)/Smad signaling pathway and improving the interaction between collagen and α2β1 integrin. The results indicated that CHs from fish could be applied to alleviate osteoporosis or treat bone loss.

Biological effect of hydrolyzed collagen on bone metabolism

Osteoporosis is a chronic and asymptomatic disease characterized by low bone mass and skeletal microarchitectural deterioration, increased risk of fracture, and associated comorbidities most prevalent in the elderly. Due to an increasingly aging population, osteoporosis has become a major health issue requiring innovative disease management. Proteins are important for bone by providing building blocks and by exerting specific regulatory function. This is why adequate protein intake plays a considerable role in both bone development and bone maintenance. More specifically, since an increase in the overall metabolism of collagen can lead to severe dysfunctions and a more fragile bone matrix and because orally administered collagen can be digested in the gut, cross the intestinal barrier, enter the circulation, and become available for metabolic processes in the target tissues, one may speculate that a collagen-enriched diet provides benefits for the skeleton. Collagen-derived products such as gelatin or hydrolyzed collagen (HC) are well acknowledged for their safety from a nutritional point of view; however, what is their impact on bone biology? In this manuscript, we critically review the evidence from literature for an effect of HC on bone tissues in order to determine whether HC may represent a relevant alternative in the design of future nutritional approaches to manage osteoporosis prevention.

A Possible Wound Dressing Material from Marine Food Waste

Purpose

Bluefin Trevally (Caranx melampygus) fish is mainly used for fillet production, the bones of which are discarded as a major solid waste in the fish food processing industry. In the present study, novel collagen films were prepared using the bones of Bluefin Trevally (BT). The study investigates the potential of using this collagen film as a wound dressing material.

Methods

The prepared collagen films (CFs) were characterized for their physicochemical properties using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), atomic force microscopy (AFM), tensile strength, elongation at break, etc. In vitro studies using human keratinocyte cell line (HaCaT) also proved the biocompatibility of CF. The CFs were used as wound dressing material on the experimental wounds of rats and the healing pattern was evaluated using planimetric and histopathological studies.

Results

CF prepared from the bones of BT possessed better mechanical properties. The in vitro studies demonstrated its biocompatible nature. Acceleration of wound healing in CF-treated rats was evident in the in vivo studies.

Conclusions

The study has devised a process for using fish waste in the preparation of a value-added product like wound dressing material. The CF with the required strength, biocompatibility and wound healing properties may be tried as a wound dressing material in large animals after obtaining the necessary approval.

Skin Antiageing and Systemic Redox Effects of Supplementation with Marine Collagen Peptides and Plant-Derived Antioxidants: A Single-Blind Case-Control Clinical Study

Recently, development and research of nutraceuticals based on marine collagen peptides (MCPs) have been growing due to their high homology with human collagens, safety, bioavailability through gut, and numerous bioactivities. The major concern regarding safety of MCPs intake relates to increased risk of oxidative stress connected with collagen synthesis (likewise in fibrosis) and to ROS production by MCPs-stimulated phagocytes. In this clinical-laboratory study, fish skin MCPs combined with plant-derived skin-targeting antioxidants (AO) (coenzyme Q10 + grape-skin extract + luteolin + selenium) were administered to volunteers (n = 41). Skin properties (moisture, elasticity, sebum production, and biological age) and ultrasonic markers (epidermal/dermal thickness and acoustic density) were measured thrice (2 months before treatment and before and after cessation of 2-month oral intake). The supplementation remarkably improved skin elasticity, sebum production, and dermal ultrasonic markers. Metabolic data showed significant increase of plasma hydroxyproline and ATP storage in erythrocytes. Redox parameters, GSH/coenzyme Q10 content, and GPx/GST activities were unchanged, while NO and MDA were moderately increased within, however, normal range of values. Conclusions. A combination of MCPs with skin-targeting AOs could be effective and safe supplement to improve skin properties without risk of oxidative damage.

Biocompatibility of Novel Type I Collagen Purified from Tilapia Fish Scale: An In Vitro Comparative Study

Type I collagen (COL-1) is the prevailing component of the extracellular matrix in a number of tissues including skin, ligament, cartilage, bone, and dentin. It is the most widely used tissue-derived natural polymer. Currently, mammalian animals, including pig, cow, and rat, are the three major sources for purification of COL-1. To reduce the risk of zoonotic infectious diseases transmission, minimize the possibility of immunogenic reaction, and avoid problems related to religious issues, exploration of new sources (other than mammalian animals) for the purification of type I collagen is highly desirable. Hence, the purpose of the current study was to investigate the in vitro responses of MDPC-23 to type I collagen isolated from tilapia scale in terms of cellular proliferation, differentiation, and mineralization. The results suggested that tilapia scale collagen exhibited comparable biocompatibility to porcine skin collagen, indicating it might be a potential alternative to type I collagen from mammals in the application for tissue regeneration in oral-maxillofacial area.

Bioactive Carbohydrates and Peptides in Foods: An Overview of Sources, Downstream Processing Steps and Associated Bioactivities

Bioactive peptides and carbohydrates are sourced from a myriad of plant, animal and insects and have huge potential for use as food ingredients and pharmaceuticals. However, downstream processing bottlenecks hinder the potential use of these natural bioactive compounds and add cost to production processes. This review discusses the health benefits and bioactivities associated with peptides and carbohydrates of natural origin and downstream processing methodologies and novel processes which may be used to overcome these.

On the Collagen Mineralization. A Review

Collagen mineralization (CM) is a challenging process that has received a lot of attention in the past years. Among the reasons for this interest, the key role is the importance of collagen and hydroxyapatite in natural bone, as major constituents. Different protocols of mineralization have been developed, specially using simulated body fluid (SBF) and many methods have been used to characterize the systems obtained, starting with methods of determining the mineral content (XRD, FTIR, Raman, High-Resolution Spectral Ultrasound Imaging), continuing with imaging methods (AFM, TEM, SEM, Fluorescence Microscopy), thermal analysis (DSC and TGA), evaluation of the mechanical and biological properties, including statistical methods and molecular modeling. In spite of the great number of studies regarding collagen mineralization, its mechanism, both in vivo and in vitro, is not completely understood. Some of the methods used in vitro and investigation methods are reviewed here.

Collagen-derived dipeptide prolyl-hydroxyproline promotes differentiation of MC3T3-E1 osteoblastic cells

Prolyl-hydroxyproline (Pro-Hyp) is one of the major constituents of collagen-derived dipeptides. The objective of this study was to investigate the effects of Pro-Hyp on the proliferation and differentiation of MC3T3-E1 osteoblastic cells. Addition of Pro-Hyp did not affect MC3T3-E1 cell proliferation and matrix mineralization but alkaline phosphatase activity was significantly increased. Furthermore, cells treated with Pro-Hyp significantly upregulated gene expression of Runx2, Osterix, and Col1α1. These results indicate that Pro-Hyp promotes osteoblast differentiation. This study demonstrates for the first time that Pro-Hyp has a positive effect on osteoblast differentiation with upregulation of Runx2, Osterix, and Collα1 gene expression.

Bovine collagen peptides compounds promote the proliferation and differentiation of MC3T3-E1 pre-osteoblasts

Objective

Collagen peptides (CP) compounds, as bone health supplements, are known to play a role in the treatment of osteoporosis. However, the molecular mechanisms of this process remain unclear. This study aimed to investigate the effects of bovine CP compounds on the proliferation and differentiation of MC3T3-E1 cells.

Methods

Mouse pre-osteoblast cell line MC3T3-E1 subclone 4 cells were treated with bovine CP compounds. Cell proliferation was analyzed by MTT assays and the cell cycle was evaluated by flow cytometry scanning. Furthermore, MC3T3-E1 cell differentiation was analyzed at the RNA level by real-time PCR and at the protein level by western blot analysis for runt-related transcription factor 2 (Runx2), a colorimetric p-nitrophenyl phosphate assay for alkaline phosphatase (ALP), and ELISA for osteocalcin (OC). Finally, alizarin red staining for mineralization was measured using Image Software Pro Plus 6.0.

Results

Cell proliferation was very efficient after treatment with different concentrations of bovine CP compounds, and the best concentration was 3 mg/mL. Bovine CP compounds significantly increased the percentage of MC3T3-E1 cells in G₂/S phase. Runx2 expression, ALP activity, and OC production were significantly increased after treatment with bovine CP compounds for 7 or 14 days. Quantitative analyses with alizarin red staining showed significantly increased mineralization of MC3T3-E1 cells after treatment with bovine CP compounds for 14 or 21 days.

Conclusions

Bovine CP compounds increased osteoblast proliferation, and played positive roles in osteoblast differentiation and mineralized bone matrix formation. Taking all the experiments together, our study indicates a molecular mechanism for the potential treatment of osteoarthritis and osteoporosis.

Potency of fish collagen as a scaffold for regenerative medicine

Cells, growth factors, and scaffold are the crucial factors for tissue engineering. Recently, scaffolds consisting of natural polymers, such as collagen and gelatin, bioabsorbable synthetic polymers, such as polylactic acid and polyglycolic acid, and inorganic materials, such as hydroxyapatite, as well as composite materials have been rapidly developed. In particular, collagen is the most promising material for tissue engineering due to its biocompatibility and biodegradability. Collagen contains specific cell adhesion domains, including the arginine-glycine-aspartic acid (RGD) motif. After the integrin receptor on the cell surface binds to the RGD motif on the collagen molecule, cell adhesion is actively induced. This interaction contributes to the promotion of cell growth and differentiation and the regulation of various cell functions. However, it is difficult to use a pure collagen scaffold as a tissue engineering material due to its low mechanical strength. In order to make up for this disadvantage, collagen scaffolds are often modified using a cross-linker, such as gamma irradiation and carbodiimide. Taking into account the possibility of zoonosis, a variety of recent reports have been documented using fish collagen scaffolds. We herein review the potency of fish collagen scaffolds as well as associated problems to be addressed for use in regenerative medicine.

Bone regenerative medicine: classic options, novel strategies, and future directions

This review analyzes the literature of bone grafts and introduces tissue engineering as a strategy in this field of orthopedic surgery. We evaluated articles concerning bone grafts; analyzed characteristics, advantages, and limitations of the grafts; and provided explanations about bone-tissue engineering technologies. Many bone grafting materials are available to enhance bone healing and regeneration, from bone autografts to graft substitutes; they can be used alone or in combination. Autografts are the gold standard for this purpose, since they provide osteogenic cells, osteoinductive growth factors, and an osteoconductive scaffold, all essential for new bone growth. Autografts carry the limitations of morbidity at the harvesting site and limited availability. Allografts and xenografts carry the risk of disease transmission and rejection. Tissue engineering is a new and developing option that had been introduced to reduce limitations of bone grafts and improve the healing processes of the bone fractures and defects. The combined use of scaffolds, healing promoting factors, together with gene therapy, and, more recently, three-dimensional printing of tissue-engineered constructs may open new insights in the near future.

Bone regenerative medicine: classic options, novel strategies, and future directions

This review analyzes the literature of bone grafts and introduces tissue engineering as a strategy in this field of orthopedic surgery. We evaluated articles concerning bone grafts; analyzed characteristics, advantages, and limitations of the grafts; and provided explanations about bone-tissue engineering technologies. Many bone grafting materials are available to enhance bone healing and regeneration, from bone autografts to graft substitutes; they can be used alone or in combination. Autografts are the gold standard for this purpose, since they provide osteogenic cells, osteoinductive growth factors, and an osteoconductive scaffold, all essential for new bone growth. Autografts carry the limitations of morbidity at the harvesting site and limited availability. Allografts and xenografts carry the risk of disease transmission and rejection. Tissue engineering is a new and developing option that had been introduced to reduce limitations of bone grafts and improve the healing processes of the bone fractures and defects. The combined use of scaffolds, healing promoting factors, together with gene therapy, and, more recently, three-dimensional printing of tissue-engineered constructs may open new insights in the near future.

Potential application of hydrolyzed fish collagen for inducing the multidirectional differentiation of rat bone marrow mesenchymal stem cells

Hydrolyzed fish collagen (HFC) has recently attracted considerable attention because of its outstanding bioactivity. However, few studies have been performed to determine the biological effects of HFC on bone marrow mesenchymal stem cells (BMSCs), which are often used in regenerative medicine. In this study, the molecular weight, amino acid composition, and contact angle of HFC were measured. The influence of HFC on cell viability and the multidirectional differentiation of BMSCs into osteogenic, endothelial, adipogenic, chondrogenic, and neural lineages were also assessed. Furthermore, the mechanism by which HFC promotes osteogenesis was investigated at the protein level. The molecular weight of HFC ranged from 700 to 1300 Da, the contact angle of HFC was approximately 26°, and HFC was found to be composed of various amino acids, including glycine, proline, and hydroxyproline. At a concentration of 0.2 mg/mL, HFC promoted cell viability, and significantly up-regulated the expression of osteogenic markers (RUNX2, ALP, OPN, and OCN), as well as endothelial markers (CD31, VE-cadherin, and VEGFR2). Western blot results indicated that treatment of BMSCs with 0.2 mg/mL HFC could activate the MAPK/ERK signaling pathway and then increase the protein level of RUNX2, while treatment with PD98059, a specific inhibitor of ERK1/2, could significantly inhibit the expression of P-ERK and RUNX2. Interestingly, real-time PCR demonstrated that HFC inhibited the expression of adipogenic markers (LPL and ADFP) and chondrogenic markers (aggrecan and COLII), whereas it had no effect on neural differentiation markers (MAP2 and β3-tubulin). In summary, this study suggests that without the use of any additional inducing reagent, HFC has the potential to actively promote osteogenic and endothelial differentiation because of its high hydrophilicity and the optimal extracellular microenvironment supplied by its amino acids. This research also revealed that HFC inhibited adipogenic and chondrogenic differentiation, but it had no influence on the neural differentiation of rat bone marrow mesenchymal stem cells (rBMSCs).