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Cold Spring Harbor Perspectives in... Jan 2011Collagens are the most abundant proteins in mammals. The collagen family comprises 28 members that contain at least one triple-helical domain. Collagens are deposited in... (Review)
Review
Collagens are the most abundant proteins in mammals. The collagen family comprises 28 members that contain at least one triple-helical domain. Collagens are deposited in the extracellular matrix where most of them form supramolecular assemblies. Four collagens are type II membrane proteins that also exist in a soluble form released from the cell surface by shedding. Collagens play structural roles and contribute to mechanical properties, organization, and shape of tissues. They interact with cells via several receptor families and regulate their proliferation, migration, and differentiation. Some collagens have a restricted tissue distribution and hence specific biological functions.
Topics: Collagen; Genetic Variation; Mutation; Promoter Regions, Genetic; Protein Conformation; Protein Structure, Tertiary; Receptors, Collagen
PubMed: 21421911
DOI: 10.1101/cshperspect.a004978 -
Nutricion Hospitalaria Jul 2015Hydrolysate Collagen (HC) consists of small peptides with a molecular weight lower than 5.000 Da. produced from gelatinization and subsequent enzymatic hydrolysis of... (Review)
Review
INTRODUCTION
Hydrolysate Collagen (HC) consists of small peptides with a molecular weight lower than 5.000 Da. produced from gelatinization and subsequent enzymatic hydrolysis of native collagen which is found in rich collagenic animal tissues. There is much evidence about the HC ingestion positive effect over degenerative joint and bones diseases.
OBJECTIVE
The aim of this article is to review the present scientific studies about HC and to evaluate the HC ingestion therapeutical effects on some collagenic tissues as cartilage, bones and skin.
RESULTS
Up to date, there are more than 60 scientific studies (in vitro, in vivo, clinics and on bioavailability) about HC ingestion efficacy on reducing collagen damage and loss consequences as joint pain and erosion (osteoarthritis), bone density loss (osteoporosis) and skin ageing.
CONCLUSIONS
Preclinical studies show that HC stimulates collagenic tissue regeneration by increasing not only collagen synthesis but minor components (glycosaminoglycans and hyaluronic acid) synthesis as well. Clinical studies show that HC continual ingestion helps to reduce and prevent joint pain, bone density loss and skin ageing. These results as well as its high level of tolerance and safety make HC ingestion attractive for a long-term use in bone and joint degenerative diseases and in fight against skin ageing.
Topics: Aging; Animals; Bone and Bones; Clinical Studies as Topic; Collagen; Dietary Supplements; Drug Evaluation, Preclinical; Health Status; Humans; Joints; Skin Physiological Phenomena
PubMed: 26267777
DOI: 10.3305/nh.2015.32.sup1.9482 -
Cell and Tissue Research Jan 2010Integrins are cell adhesion receptors that are evolutionary old and that play important roles during developmental and pathological processes. The integrin family is... (Review)
Review
Integrins are cell adhesion receptors that are evolutionary old and that play important roles during developmental and pathological processes. The integrin family is composed of 24 alphabeta heterodimeric members that mediate the attachment of cells to the extracellular matrix (ECM) but that also take part in specialized cell-cell interactions. Only a subset of integrins (8 out of 24) recognizes the RGD sequence in the native ligands. In some ECM molecules, such as collagen and certain laminin isoforms, the RGD sequences are exposed upon denaturation or proteolytic cleavage, allowing cells to bind these ligands by using RGD-binding receptors. Proteolytic cleavage of ECM proteins might also generate fragments with novel biological activity such as endostatin, tumstatin, and endorepellin. Nine integrin chains contain an alphaI domain, including the collagen-binding integrins alpha1beta1, alpha2beta1, alpha10beta1, and alpha11beta1. The collagen-binding integrins recognize the triple-helical GFOGER sequence in the major collagens, but their ability to recognize these sequences in vivo is dependent on the fibrillar status and accessibility of the interactive domains in the fibrillar collagens. The current review summarizes some basic facts about the integrin family including a historical perspective, their structure, and their ligand-binding properties.
Topics: Animals; Collagen; Extracellular Matrix Proteins; Humans; Integrins; Oligopeptides; Protein Structure, Quaternary
PubMed: 19693543
DOI: 10.1007/s00441-009-0834-6 -
Cell and Tissue Research Jan 2010The collagens represent a family of trimeric extracellular matrix molecules used by cells for structural integrity and other functions. The three alpha chains that form... (Review)
Review
The collagens represent a family of trimeric extracellular matrix molecules used by cells for structural integrity and other functions. The three alpha chains that form the triple helical part of the molecule are composed of repeating peptide triplets of glycine-X-Y. X and Y can be any amino acid but are often proline and hydroxyproline, respectively. Flanking the triple helical regions (i.e., Col domains) are non-glycine-X-Y regions, termed non-collagenous domains. These frequently contain recognizable peptide modules found in other matrix molecules. Proper tissue function depends on correctly assembled molecular aggregates being incorporated into the matrix. This review highlights some of the structural characteristics of collagen types I-XXVIII.
Topics: Amino Acid Motifs; Animals; Collagen; Humans; Hydroxyproline; Protein Structure, Tertiary; Structure-Activity Relationship
PubMed: 19693541
DOI: 10.1007/s00441-009-0844-4 -
Cancer Research May 2023Collagen is one of the most abundant proteins in animals and a major component of the extracellular matrix (ECM) in tissues. Besides playing a role as a structural... (Review)
Review
Collagen is one of the most abundant proteins in animals and a major component of the extracellular matrix (ECM) in tissues. Besides playing a role as a structural building block of tissues, collagens can modulate the behavior of cells, and their deregulation can promote diseases such as cancer. In tumors, collagens and many other ECM molecules are mainly produced by fibroblasts, and recent evidence points toward a role of tumor-derived collagens in tumor progression and metastasis. In this review, we focus on the newly discovered functions of collagens in cancer. Novel findings have revealed the role of collagens in tumor dormancy and immune evasion, as well as their interplay with cancer cell metabolism. Collagens could serve as prognostic markers for patients with cancer, and therapeutic strategies targeting the collagen ECM have the potential to prevent tumor progression and metastasis.
Topics: Animals; Collagen; Neoplasms; Extracellular Matrix; Fibroblasts
PubMed: 36638361
DOI: 10.1158/0008-5472.CAN-22-2034 -
Biophysical Journal Jul 2016Type I collagen is the predominant collagen in mature tendons and ligaments, where it gives them their load-bearing mechanical properties. Fibrils of type I collagen are...
Type I collagen is the predominant collagen in mature tendons and ligaments, where it gives them their load-bearing mechanical properties. Fibrils of type I collagen are formed by the packing of polypeptide triple helices. Higher-order structures like fibril bundles and fibers are assembled from fibrils in the presence of other collagenous molecules and noncollagenous molecules. Curiously, however, experiments show that fibrils/fibril bundles are less resistant to axial stress compared to their constituent triple helices-the Young's moduli of fibrils/fibril bundles are an order-of-magnitude smaller than the Young's moduli of triple helices. Given the sensitivity of the Young's moduli of triple helices to solvation environment, a plausible explanation is that the packing of triple helices into fibrils perhaps reduces the Young's modulus of an individual triple helix, which results in fibrils having smaller Young's moduli. We find, however, from molecular dynamics and accelerated conformational sampling simulations that the Young's modulus of the buried core of the fibril is of the same order as that of a triple helix in aqueous phase. These simulations, therefore, suggest that the lower Young's moduli of fibrils/fibril bundles cannot be attributed to the specific packing of triple helices in the fibril core. It is not the fibril core that yields initially to axial stress. Rather, it must be the portion of the fibril exposed to the solvent and/or the fibril-fibril interface that bears the initial strain. Overall, this work provides estimates of Young's moduli and persistence lengths at two levels of collagen's structural assembly, which are necessary to quantitatively investigate the response of various biological factors on collagen mechanics, including congenital mutations, posttranslational modifications and ligand binding, and also engineer new collagen-based materials.
Topics: Biomechanical Phenomena; Collagen Type I; Elastic Modulus; Mechanical Phenomena; Molecular Dynamics Simulation; Nanotechnology; Protein Structure, Secondary
PubMed: 27410733
DOI: 10.1016/j.bpj.2016.05.038 -
Theranostics 2022The skin epidermis and appendages undergo ongoing renewal throughout life. Stem cells residing in the epidermis and hair follicles are pivotal for sustaining skin... (Review)
Review
The skin epidermis and appendages undergo ongoing renewal throughout life. Stem cells residing in the epidermis and hair follicles are pivotal for sustaining skin homeostasis. The self-renewal ability of stem cells significantly decreases during skin aging but actively increases during wound repair. Residential stem cells reside in niches that provide spatially distinct microenvironments for stem cell maintenance and function. Cell-extracellular matrix (ECM) adhesion is essential for the establishment of niche architecture. Collagen XVII (COL17), as a transmembrane protein constituting hemidesmosomes (HDs), mediates the interactions of stem cells with surrounding cells and the matrix to regulate skin homeostasis, aging and wound repair. This review focuses on the pivotal role of the niche component COL17 in stem cell maintenance and its function in regulation of skin aging and wound repair.
Topics: Autoantigens; Non-Fibrillar Collagens; Skin Aging; Stem Cell Niche; Collagen Type XVII
PubMed: 36185608
DOI: 10.7150/thno.78016 -
Food Research International (Ottawa,... Dec 2022Obtaining collagen from rabbit meat, skin and ears is a great way to add value to these by-products. The collagen extracts from meat, skin, and ear showed high levels of...
Obtaining collagen from rabbit meat, skin and ears is a great way to add value to these by-products. The collagen extracts from meat, skin, and ear showed high levels of protein 80.7, 95.5, and 94.5% and yields of 9.0, 24.4, and 23.8% on a dry basis, respectively. SDS-PAGE analysis showed that the collagens mainly consist of type I collagen, and the FTIR spectra displayed the characteristic peaks of amide A, B, I, II, and III; in addition, the collagens showed greater solubility in acidic pH. The foam production capacity of the collagens was low compared with other collagen sources. However, foam rabbit-collagen stability was high. The emulsifying activity index for the meat, skin, and ears was 44.7, 46.6, and 48.2 m/g, respectively. Based on the results, the meat, skin, and ears of the rabbit proved to be a viable source for collagen extraction and a possible alternative to add value to the by-products (skin and ears) of these raw materials.
Topics: Animals; Rabbits; Collagen; Meat; Skin; Collagen Type I; Electrophoresis, Polyacrylamide Gel
PubMed: 36461217
DOI: 10.1016/j.foodres.2022.111967 -
Journal of Controlled Release :... Oct 2016As the most abundant protein in mammals and a major structural component in extracellular matrix, collagen holds a pivotal role in tissue development and maintaining the... (Review)
Review
As the most abundant protein in mammals and a major structural component in extracellular matrix, collagen holds a pivotal role in tissue development and maintaining the homeostasis of our body. Persistent disruption to the balance between collagen production and degradation can cause a variety of diseases, some of which can be fatal. Collagen remodeling can lead to either an overproduction of collagen which can cause excessive collagen accumulation in organs, common to fibrosis, or uncontrolled degradation of collagen seen in degenerative diseases such as arthritis. Therefore, the ability to monitor the state of collagen is crucial for determining the presence and progression of numerous diseases. This review discusses the implications of collagen remodeling and its detection methods with specific focus on targeting native collagens as well as denatured collagens. It aims to help researchers understand the pathobiology of collagen-related diseases and create novel collagen targeting therapeutics and imaging modalities for biomedical applications.
Topics: Collagen; Diagnostic Imaging; Drug Delivery Systems; Extracellular Matrix; Humans; Peptides; Protein Binding; Protein Denaturation
PubMed: 26773768
DOI: 10.1016/j.jconrel.2016.01.007 -
Marine Drugs Mar 2018The biosynthesis, structural diversity, and functionality of collagens of sponge origin are still paradigms and causes of scientific controversy. This review has the... (Review)
Review
The biosynthesis, structural diversity, and functionality of collagens of sponge origin are still paradigms and causes of scientific controversy. This review has the ambitious goal of providing thorough and comprehensive coverage of poriferan collagens as a multifaceted topic with intriguing hypotheses and numerous challenging open questions. The structural diversity, chemistry, and biochemistry of collagens in sponges are analyzed and discussed here. Special attention is paid to spongins, collagen IV-related proteins, fibrillar collagens from demosponges, and collagens from glass sponge skeletal structures. The review also focuses on prospects and trends in applications of sponge collagens for technology, materials science and biomedicine.
Topics: Animals; Biological Products; Collagen; Microscopy, Electron, Scanning; Porifera; Tissue Scaffolds
PubMed: 29510493
DOI: 10.3390/md16030079