Collagen Type Research Articles

Proteins Involved in Endothelial Function and Inflammation Are Implicated in Cerebral Small Vessel Disease.

Endothelial dysfunction and inflammation have been implicated in the pathophysiology of cerebral small vessel disease (SVD). However, whether they are causal, and if so which components of the pathways represent potential treatment targets, remains uncertain. Two-sample Mendelian randomization (MR) was used to test the association between the circulating abundance of 996 proteins involved in endothelial dysfunction and inflammation and SVD. The genetic instruments predicting protein levels were obtained from the Iceland 36K (n=35 892) and the UK Biobank Proteomics (n=34 557) cohorts, both of which were longitudinal studies with follow-up from 2000 to 2023 and 2006 to 2023, respectively. SVD was represented by lacunar stroke (n=6030 cases) and 5 neuroimaging features (white matter hyperintensities [n=55 291], diffusion tensor imaging metrics: mean diffusivity [n=36 460] and fractional anisotropy [n=36 533], extensive white matter perivascular space burden [n=9324 cases], and cerebral microbleeds [n=3556 cases]). Among the proteins supported by causal evidence from the MR, cross-sectional analysis was performed to assess their associations with cognitive performance; survival analysis with Fine-Gray models was applied to examine their associations with incident all-cause dementia and stroke within the UK Biobank Proteomics cohort. MR suggested COL2A1 (collagen type II α-1 chain) was associated with lacunar stroke (odds ratio, 0.89 [95% CI, 0.86-0.91]; P=5×10-5). Moreover, 12 proteins related to endothelial function and inflammation were associated with neuroimaging features of SVD. Cross-sectional analyses showed 5 of the 13 proteins (EPHA2 [ephrin type-A receptor 2], METAP1D [methionine aminopeptidase 1D, mitochondrial], FLT4 [vascular endothelial growth factor receptor 3], COL2A1, and TIMD4 [T-cell immunoglobulin and mucin domain-containing protein 4]) were associated with cognitive performance with effects concordant with their MR findings. Survival analyses with the Fine-Gray models indicated that 5 of the 13 proteins (EPHA2, METAP1D, FLT4, APOE [apolipoprotein E], and PDE5A [cGMP-specific 3',5'-cyclic phosphodiesterase]) were associated with the risk of all-cause dementia or stroke independent of age and sex, consistent with their MR evidence. Our findings suggest that endothelial-platelet activation and complement-mediated regulation of inflammation play roles in SVD and identify potential therapeutic targets and pathways.

Determination of collagen types and mineral contents in fish skin and collagen-containing skin-derived protein hydrolysates before and after in vitro simulated digestion.

An in vitro digestion model was established to characterize the types of collagens in skin of cod, white fish, and salmon as well as their collagen-containing skin-derived protein hydrolysates (CSPH) before and after digestion. Moreover, the mineral content and their bioaccessibility were evaluated. Finally, the presence of heavy metals was evaluated to assess the safety of these products. The results showed that white fish protein exhibited a high digestibility, reaching up to 92%. Among the collagen products, salmon collagen had the highest digestibility (∼73%). Protein identification revealed that the emPAI of type I collagen in digested skin and CSPH was higher than that of undigested samples. In addition, raw skins had higher contents of P, K, Ca and Mg, and the mineral content of CSPH was lower than that of unprocessed skins. Among the minerals studied, Ca and Cu showed the highest bioaccessibility in raw skin cod, being 32% and 26%, respectively. The bioaccessibility of Cu in raw skin salmon was also higher (∼34%). Moreover, in CSPH, Mg, K and Cu can be easily digested and absorbed. Regarding heavy metals, As and Pb were below the respective safe limits in all raw skins and CSPH, while Hg and Cd were not detected in the fish CSPH. Fish-derived collagen has gained significant attention due to its numerous health benefits, high bioavailability, and superior sustainability compared to animal collagen. Moreover, different types of collagens offer distance roles and advantages in the body. However, there are limited reports on how collagen structure and type may change during the digestive process. This study seeks to deepen our understanding of the economic value of fish collagen, as well as the mechanisms of its absorption and digestion. By investigating processes, the research aims to provide a clearer insight into the physiological effects of fish-derived collagen, which can inform the development of tailored collagen supplementation programs based on specific health needs.

Investigating the antioxidant and anti-inflammatory potential of Nypa fruticans: a multifaceted approach to skin protection and aging

Reactive oxygen species (ROS) produced in the mitochondria of skin cells play a significant role in the degradation of the extracellular matrix and induction of inflammatory responses, both of which are major contributors to skin aging. Antioxidants that reduce ROS production and inhibit inflammatory skin lesions are considered beneficial for the treatment of inflammatory skin diseases and prevention of skin aging. In this study, we evaluated the potential of Nypa fruticans (NF), which is known for its antioxidant properties, to mitigate tumor necrosis factor-alpha (TNF-α)- and interferon-gamma (IFN-γ)-induced damage in normal human epidermal keratinocytes. The major active constituents identified in NF include protocatechuic acid, hydroxybenzoic acid, procyanidin B, catechin, and epicatechin. NF significantly suppressed the production of ROS, nitric oxide (NO), and prostaglandin E2 (PGE2), while also reducing the levels of inflammatory cytokines interleukin-6 (IL-6) and interleukin-1 beta (IL-1β), which were elevated by TNF-α/IFN-γ stimulation. Furthermore, NF restored the expression of key skin barrier-related proteins such as serine peptidase inhibitor kazal type 5 (SPINK5), collagen type I alpha 1 chain (COLIA1), loricrin (LOR), aquaporin-3 (AQP3), and filaggrin (FLG). Additionally, NF significantly upregulated the expression of hyaluronan synthase (HAS) -1 and − 2 and human β-defensin (HBD) -2 and − 3, which are important for skin hydration and innate immune defense. These findings underscore the potential therapeutic applications of Nypa fruticans (NF) in mitigating oxidative stress, inflammation, skin barrier dysfunction, dehydration, and microbial imbalances. By targeting multiple pathways implicated in skin aging, NF represents a promising comprehensive approach for preserving skin health and addressing age-related dermatological conditions. Moreover, NF holds significant potential not only to alleviate the manifestations of skin aging but also to provide a basis for the development of innovative dermatological therapies. Future investigations should aim to further elucidate the clinical applications of NF in dermatology to maximize its therapeutic benefits.

Mizagliflozin ameliorates diabetes induced kidney injury by inhibitor inhibit inflammation and oxidative stress.

Mizagliflozin (MIZ) is a specific inhibitor of sodium-glucose cotransport protein 1 (SGLT1) originally developed as a medication for diabetes. To explore the impact of MIZ on diabetic nephropathy (DN). Diabetic mice were created using db/db mice. They were administered either a low dose (0.5 mg/kg) or a high dose (1.0 mg/kg) of the SGLT1 inhibitor MIZ via stomach gavage for 8 weeks. Subsequently, mesangial cells (MCs) were isolated and subjected to high glucose conditions in culture to assess the effects of MIZ on DN. The results showed that low doses of MIZ significantly reduced albuminuria to a level comparable to that achieved with high doses in db/db mice. High doses of MIZ led to a substantial increase in body weight in mice, along with decreased blood glucose levels and food intake. Moreover, the intervention with high-dose MIZ notably decreased the expression of extracellular matrix genes, such as collagen type 1 alpha 1 mRNA levels. While the expression of SGLT1 increased after exposure to high glucose, it decreased following treatment with MIZ. Furthermore, MIZ intervention was more effective in improving lactate dehydrogenase levels in MCs induced by high glucose compared to canagliflozin. MIZ also significantly elevated levels of antioxidant enzymes superoxide dismutase, catalase, and glutathione, while reducing malondialdehyde levels. These findings indicate that MIZ can ameliorate DN by inhibiting SGLT1, inflammation, and oxidative stress.

Biomechanically inspired composite hydrogel bioink enhances engineered cartilage formation

Current therapies for articular cartilage defects or degeneration (osteoarthritis) remain unsatisfactory. There are significant clinical demands for the development of more efficient approaches to enhance the repair or regeneration of articular cartilage lesions. In this study, a newly defined alginate-gelatin (A-G) composite bioink was synthesized using the carbodiimide chemistry crosslinking method. Then, the dual-crosslinking (DC) bioscaffolds containing both chemical and ionic networks were fabricated by 3D-bioprinting technique and Ca2+ treatment. The optimized networks formed in the DC bioscaffolds provided a desirable Young’s modulus and geometric constraints, which were superior to that of the single-crosslinking (SC) control group to mimic the mechanical properties of the pericellular matrix (PCM) of native articular cartilage. Chondrocytes exhibited above 95% viability and higher proliferation rate in the 3D printed A-G-DC bioscaffolds than in the alginate-only group after 7 days in vitro culture. Chondrogenic differentiation in vitro was improved in the A-G-DC bioscaffolds than that of the alginate-only group, indexed by upregulation of chondrogenic marker gene expression including Sox9, Col2a1, Comp and Aggrecan. In the subcutaneous transplantation model and osteochondral defect model in mice with severe combined immunodeficiency (SCID), the A-G-DC bioscaffolds exhibited enhanced chondrogenesis and repair capacity than the alginate-only or none-implant control group, characterized by the increased expression of SOX9 and collagen type II (Col II) and higher ICRS II scores, respectively. These findings demonstrated that the biomechanically inspired A-G composite bioink and the 3D-printed A-G-DC bioscaffolds possess excellent cell biocompatibility, satisfactory biomechanical properties and chondrogenesis promotion capacity, which have the potential to be applied to enhance cartilage regeneration for patients with articular cartilage lesions.

Potential of Trilayered Gelatin/Polycaprolactone Nanofibers for Periodontal Regeneration: An In Vitro Study

Over the past few years, biomaterial-based periodontal tissue engineering has gained popularity. An ideal biomaterial for treating periodontal defects is expected to stimulate periodontal-derived cells, allowing them to contribute most efficiently to tissue reconstruction. The present study focuses on evaluating the in vitro behavior of human periodontal ligament-derived stromal cells (hPDL-MSCs) when cultured on gelatin/Polycaprolactone prototype (GPP) and volume-stable collagen matrix (VSCM). Cells were cultured onto the GPP, VSCM, or tissue culture plate (TCP) for 3, 7, and 14 days. Cell morphology, adhesion, proliferation/viability, the gene expression of Collagen type I, alpha1 (COL1A1), Vascular endothelial growth factor A (VEGF-A), Periostin (POSTN), Cementum protein 1 (CEMP1), Cementum attachment protein (CAP), Interleukin 8 (IL-8) and Osteocalcin (OCN), and the levels of VEGF-A and IL-8 proteins were investigated. hPDL-MSCs attached to both biomaterials exhibited a different morphology compared to TCP. GPP exhibited stronger capabilities in enhancing cell viability and metabolic activity compared to VSCM. In most cases, the expression of all investigated genes, except POSTN, was stimulated by both materials, with GPP having a superior effect on COL1A1 and VEGF-A, and VSCM on OCN. The IL-8 protein production was slightly higher in cells grown on VSCM. GPP also exhibited the ability to absorb VEGF-A protein. The gene expression of POSTN was promoted by GPP and slightly suppressed by VSCM. In summary, our findings indicate that GPP electrospun nanofibers effectively promote the functional performance of PDLSCs in periodontal regeneration, particularly in the periodontal ligament and cementum compartment.

CircZMYM2 Alleviates TGF-β1-Induced Proliferation, Migration and Activation of Fibroblasts via Targeting miR-199b-5p/KLF13 Axis.

Dysregulated circular RNAs (circRNAs) has been revealed to be involved in pulmonary fibrosis progression. Herein, this study focused on exploring the function and mechanism of circRNA Zinc Finger MYM-Type Containing 2 (circZMYM2) on idiopathic pulmonary fibrosis (IPF) using transforming growth factor (TGF)-β1-stimulated fibroblasts. Human fibroblast cell lines IMR-90 and HFL1 were stimulated with TGF-β1 to mimic fibrosis condition in vitro. Levels of genes and proteins were detected by qRT-PCR and western blotting. Cell proliferation and migration were analyzed using cell counting kit-8 assay, 5-Ethynyl-2'-deoxyuridine (EdU) and wound healing assays. The fibrosis progression was determined by the change of E-cadherin, α-smooth muscle actin (α-SMA), collagen type I α 1 (COL1A1) and collagen type III α 1 (COL3A1). The interaction between miR-199b-5p and circZMYM2 or KLF13 (Kruppel Like Factor 13) was analyzed using dual-luciferase reporter, RIP and RNA-pull-down assays. CircZMYM2 was decreased in TGF-β1-induced IMR-90 and HFL1 fibroblasts. Functionally, re-expression of circZMYM2 in IMR-90 and HFL1 cells could attenuate TGF-β1-evoked proliferation, migration and fibrosis in cells. Mechanistically, the circZMYM2/miR-199b-5p/KLF13 constituted a competing endogenous RNA (ceRNA). TGF-β1 reduced KLF13 expression and increased miR-199b-5p expression in IMR-90 and HFL1 cells. Further rescue experiments suggested that miR-199b-5p up-regulation or KLF13 knockdown reversed the anti-fibrotic effects of circZMYM2; moreover, silencing of miR-199b-5p exhibited anti-fibrotic effects, which was counteracted by KLF13 knockdown. CircZMYM2 had an anti-fibrotic effect that could suppress fibroblast activation via miR-199b-5p/KLF13 axis, pointing a novel perspective into the potential action pattern of circ_0022383 in IPF.

A novel COL3A1 gene variant associated with sudden death due to spontaneous pneumothorax.

Spontaneous pneumothorax (SP) is a condition defined by abnormal gas accumulation in the chest cavity. Mutations of the collagen type III alpha 1 chain, COL3A1 gene, are primarily linked to vascular Ehlers-Danlos syndrome (vEDS); however, they can also contribute to structural changes in the tissue, like bullae of the lungs. In this case report, we present a young, thinly built boy who died due to a spontaneous pneumothorax. Post-mortem genetic testing revealed a novel COL3A1 mutation, likely contributing to the pathogenic events underlying death due to spontaneous pneumothorax. We recommend implementing genetic testing of correlative or causative genes in the context of SP.

Sex Differences in Aortic Valve Inflammation and Remodeling in Chronic Severe Aortic Regurgitation.

Background: Aortic regurgitation (AR) is more prevalent in male, although cellular and molecular mechanisms underlying the sex differences in prevalence and pathophysiology are unknown. Objectives: This study evaluates the impact of sex on aortic valve (AV) inflammation and remodeling as well as the cellular differences in valvular interstitial cells (VICs) and valvular endothelial cells (VECs) in patients with AR. Methods: A total of 144 patients (27.5% female) with severe chronic AR were included. AVs were analyzed by imaging, histological and molecular biology techniques (ELISA, RT-PCR). VICs and VECs isolated from patients with AR were characterized and further treated with transforming growth factor (TGF)-β. Results: Anatomically, male had smaller index aortic dimensions and greater AV thickness. Proteome profiler analyzes in AVs (n=40/sex) evidenced higher expression of inflammatory markers in male and that was further validated (interleukins, chemokines). Histological composition showed higher expression of inflammatory mediators and collagen thick fibers in AVs from male. Male VICs and VECs secreted higher levels of inflammatory markers than female cells. Interestingly, male VICs produced higher amounts of collagen type I and lower fibronectin and aggrecan, whereas male VECs secreted lower decorin. TGF-β exclusively enhanced inflammation in male VICs, and decorin and aggrecan in female VICs. Conclusion: Compared to male, AVs from female were thinner, less inflamed and fibrotic. VIC seem to be the key cell type responsible for the sex-differences. Valvular inflammation associated with an active remodeling process could be a key pathophysiological process involved in AR.

Critical role for Transglutaminase 2 in scleroderma skin fibrosis and in the development of dermal sclerosis in a mouse model of scleroderma.

Scleroderma is a life-threatening autoimmune disease characterized by inflammation, tissue remodelling, and fibrosis. This study aimed to investigate the expression and function of transglutaminase 2 (TGM2) in scleroderma skin and experimentally-induced dermal fibrosis to determine its potential role and therapeutic implications. We performed immunohistochemistry on skin sections to assess TGM2 expression and localisation, and protein biochemistry of both SSc-derived and healthy control dermal fibroblasts to assess TGM2 expression, function and ECM deposition in the presence of a TGM2 and TGFβ neutralizing antibodies and a small molecule inhibitor of the TGFβRI kinase. Mice with a complete deficiency of TGM2 (Tgm2-/-) were investigated in the bleomycin-induced model of skin fibrosis. TGM2 was found to be widely expressed in both control and scleroderma skin samples, as well as in cultured fibroblasts. Scleroderma fibroblasts exhibited elevated TGM2 expression, which correlated with increased expression of fibrosis markers (collagen type 1, αSMA and CCN2). Inhibition of TGM2 using a neutralizing antibody reduced the expression of key markers of fibrosis. The effects of TGM2 inhibition were similar to those observed with TGFβ neutralization, suggesting a potential cross-talk between TGM2 and TGFβ signalling. Moreover, TGM2 knock-out mice showed significantly reduced dermal fibrosis compared to wild-type mice. In vitro experiments with TGM2-deleted fibroblasts demonstrated impaired cell migration and collagen matrix contraction, which could be partially restored by exogenous TGFβ. TGM2 can regulate several key pro-fibrotic activities of TGFβ suggesting that attenuating TGM2 function may be of benefit in severe forms of connective tissue disease with skin fibrosis.

Leveraging the nanotopography of filamentous fungal chitin-glucan nano/microfibrous spheres (FNS) coated with collagen (type I) for scaffolded fibroblast spheroids in regenerative medicine.

Numerous naturally occurring biological structures have inspired the development of innovative biomaterials for a wide range of applications. Notably, the nanotopographical architectures found in natural materials have been leveraged in biomaterial design to enhance cell adhesion and proliferation and improve tissue regeneration for biomedical applications. In this study, we fabricated three-dimensional (3D) chitin-glucan micro/nanofibrous fungal-based spheres coated with collagen (type I) to mimic the native extracellular matrix (ECM) microenvironment. These collagen-coated fungal nano/microfibrous spheres (C-FNS) were utilized to construct 3D scaffolded spheroids of human fibroblasts through suspension culture for tissue engineering and regenerative medicine. The particle sizes of C-FNS ranged from 1.4 to 3.25 µm (average: 2.27 ± 0.38 µm), with a porosity of 81.17 %. Field emission-scanning electron microscopy (FE-SEM) revealed that C-FNS comprised continuous chitin-glucan fibers with an average diameter of 363 ± 61 nm (range: 203-512 nm), exhibiting a highly interconnected structure. The reduced arithmetic average roughness (Ra) and root mean square roughness (Rq) values of C-FNS compared to uncoated FNS suggested that collagen coating reduced surface roughness, resulting in a smoother surface that enhanced hydrophilicity, crucial for mammalian cell adhesion and spheroid formation. Moreover, the in vitro cytocompatibility of C-FNS with fibroblasts was evaluated using a resazurin-based PrestoBlue assay, which demonstrated a time-dependent increase in the metabolic activity of C-FNS/fibroblast spheroids during suspension culture for up to 14 days. FE-SEM images of C-FNS/fibroblast spheroids further revealed enhanced adhesion and proliferation of fibroblasts on the nano/microfibrous mycelial architecture, accompanied by the secretion of ECM components and formation of multilayered cell sheets over the 14-day culture period. Similarly, an assessment of the hemocompatibility of C-FNS with erythrocytes revealed the non-hemolytic properties of the biomaterial. Overall, the interaction between collagen-coated fungal chitin-glucan nano/microfibrous structures and mammalian cells holds significant potential for the development of novel, sustainable biomaterials with tailored properties for a myriad of biomedical applications, including tissue engineering, regenerative medicine, drug screening, and wound healing.

Functional Characteristics of the Crosstalk Between Vocal Fold Fibroblasts and Macrophages-The Role of Vibration in Vocal Fold Inflammation.

This in vitro study investigated the interaction between human vocal fold fibroblasts (hVFF) and macrophages under the influence of cigarette smoke extract (CSE) and vibration as potential regulators of vocal fold (VF) inflammation. Experimental in vitro pilot study. Immortalized hVFF were cultured in flexible-bottomed cell culture plates, treated with CSE, and subjected to static or dynamic conditions in a phonomimetic bioreactor. For coculture, unstimulated orlipopolysaccharide/IFNγ-stimulated THP-1 (human leukemia monocytic cell line) macrophages were added in inserts for a final 24hours of vibration period. We measured messenger ribonucleic acid (mRNA) (quantitative polymerase chain reaction [qPCR]) and protein levels (Western Blot, ELISA, and LUMINEX®) of hVFF and analyzed the results using two- and three-way ANOVA with post hoc tests. Under inflammatory stimulation, we observed a reduction of collagen (COL) type 1A1, 1A2, and 3A1, and increased gene expression of COL4A1, matrix metallopeptidase 2, and vascular endothelial growth factor A in hVFF. Additionally, the pro-inflammatory markers cyclooxygenase (COX) 1 and 2, interleukin (IL) 1β, IL-6, and IL-8 were upregulated. CSE increased COX1 and COX2 levels, whereas vibration reduced CSE-induced increases of COL4A1 and COX2 in pro-inflammatory stimulated hVFF. This study indicates that vibration may mitigate CSE-induced inflammatory damage in the hVFF, thereby offering new insights into the cellular crosstalk that underlies the pathophysiology of VF inflammation in smoking-related voice disorders.

Comparative assessment of chondral defect repair using human bone marrow- and adipose tissue-derived mesenchymal stem cells, adult and foetal articular cartilage-derived chondrocytes, and chondroprogenitors: an ex-vivo model.

Cartilage repair necessitates adjunct therapies such as cell-based approaches, which commonly use MSCs and chondrocytes but is limited by the formation of fibro-hyaline cartilage. Articular cartilage-derived chondroprogenitors(CPs) offer promise in overcoming this, as they exhibit higher chondrogenic and lower hypertrophic phenotypes. The study aimed to compare the efficacy of various cell types derived from adult and foetal cartilage suspended in platelet-rich plasma(PRP) in repairing chondral defects in an Ex-vivo Osteochondral Unit(OCU) model. In-vitro characterization of the cells included growth kinetics, FACS, qRT-PCR, and multilineage differentiation potential using histology and GAG analysis. Ex-vivo human OCUs with chondral defects containing the different cells in PRP were cultured and subjected to analysis for matrix and collagen staining. The ex-vivo OCU analysis, in terms of defect repair, showed that adult chondrocytes, sorted-CPs, and foetal MCPs displayed better host integration and filling. The In-vitro analysis of adult chondrocytes displayed greater chondrogenic genes ACAN and COL2A1 expression, with sorted-CPs also showing higher levels of ACAN. In terms of accumulation of extracellular matrix uptake evident by Safranin O staining and collagen type II fibrillar uptake, the AD-MSCs, BM-MSCs, and sorted CPs outperformed the other groups. BM-MSCs also showed corroborative higher CD146 levels, however, the gene analysis of the AD-MSCs showed a high hypertrophic tendency in terms of its COL1A1 and RUNX2 expression. Sorted chondroprogenitors outperformed both in terms of filling and hyaline-like repair, with AD-MSC and BM-MSC groups also achieving functional cartilage of a hyaline nature, warranting further evaluation using in-vivo and clinical studies.

Endocytosis-mediated healing: recombinant human collagen type III chain-induced wound healing for scar-free recovery

Endocytosis-mediated healing: recombinant human collagen type III chain-induced wound healing for scar-free recovery

Functionalization of Polyethylene Terephthalate (PETE) Membranes for the Enhancement of Cellular Adhesion in Organ-on-a-Chip Devices.

Experimental reproducibility in organ-on-chip (OOC) devices is a challenging issue, mainly caused by cell adhesion problems, as OOC devices are made of bioinert materials not suitable for natural cellularization of their surfaces. To improve cell adhesion, several surface functionalization techniques have been proposed, among which the simple use of an intermediate layer of adsorbed proteins has become the preferred one by OOC users. This way, the cells use surface receptors to adhere to the adsorbed proteins, which are in turn attached to the surface. However, as protein adsorption is based on weak electrostatic bonding between the coating proteins and the substrate, this method produces suboptimal results: as the weak electrostatic bonds break, cells detach, leading to poor, heterogeneous cellularization. To solve this problem, we present a surface functionalization method for polyethylene terephthalate (PETE) membranes, commonly used in multilayer organ-on-chip devices to support cellular layers. This protocol involves hydrolyzation of the membrane, followed by (3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS) activation, resulting in covalent bonding between the membrane and coating proteins, much stronger than the weak electrostatic bonding provided by simple adsorption. As evaluation, we first measured the effect of the functionalization protocol in the morphological and mechanical integrity of the membranes. Next, we confirmed protein coating efficiency using the ζ potential and surface tension of the functionalized membranes coated with collagen type I, polylysine, gelatin, albumin, fetal bovine serum (FBS), and Matrigel. Finally, we showed that our method significantly improves the attachment of epithelial (A549) and endothelial (EA.hy926) cell lines under static conditions, especially in collagen-coated membranes, which were further tested under dynamic conditions, showing statistically significant improvement in cell attachment compared to uncoated or collagen-adsorbed only membranes.

Regulation of fibronectin and collagens type I, III and VI by TNF-α, TGF-β, IL-13, and tofacitinib

Understanding how inflammatory cytokines influence profibrogenic wound healing responses in fibroblasts is important for understanding the pathogenesis of fibrosis. TNF-α and IL-13 are key cytokines in Th1 and Th2 immune responses, respectively, while TGF-β1 is the principal pro-fibrotic mediator. We show that 12-day fibroblast culture with TNF-α or IL-13 induces fibrogenesis, marked by progressively increasing type III and VI collagen formation, and that TGF-β1 co-stimulation amplifies these effects. Tofacitinib substantially reduced the formation of ECM proteins in response to IL-13, while fibrogenesis in response to TNF-α or TGF-β1 was marginally inhibited. The in vitro findings were supported by clinical observations in patients with active rheumatoid arthritis, which had elevated serum type III collagen formation, indicating ongoing fibrogenesis during inflammation. After 48–60 weeks of tofacitinib treatment, type III collagen degradation, aswell as formation, were significantly decreased compared to baseline, highlighting dual anti-inflammatory and anti-fibrogenic effects of tofacitinib. In contrast, other anti-inflammatory treatments including methotrexate, adalimumab and tocilizumab demonstrated anti-inflammatory effects only. Our results highlight fibro-inflammatory profiles associated with TNF-α or IL-13 stimulation, both alone and in combination with TGF-β1, and support the use of tofacitinib as an anti-fibrogenic treatment in chronic inflammatory conditions.

Production of non-triple helical collagen polypeptides under Hypoxia and the Implication for Tumor.

Non-triple helical collagen polypetides (NTHs) are alternative gene products lacking the typical collagen triple-helical structure. This study investigated NTH production in tumor cells and tissues. NTH α1(IV) was detected in various human tumor cell lines and extracted from human lung cancer tissues and tumors in mice. NTH production was significantly affected by serum concentration and occurred under hypoxic or hypoxia-mimetic conditions, even with sufficient ascorbic acid. This suggests NTHs are produced under physiological hypoxia, potentially contributing to tumor angiogenesis. NTH production generally coincided with hypoxia-inducible factor-1α (HIF-1α) accumulation, except with cobalt chloride, indicating HIF-1α isn't directly involved in NTH α1(IV) production. NTH electrophoretic mobility on SDS-PAGE was higher under hypoxia or deferoxamine treatment, likely due to suppressed lysyl hydroxylase 3 activity. This study demonstrates NTH production in tumor cells and tissues under hypoxia, suggesting their association with tumor angiogenesis and potential as therapeutic targets.

The Correlation Between the Eyelids Characteristics and Their Kinetic Performance in Two Wild Birds.

The present avian anatomists have shown a renewed interest in looking at whether the structure of the avian eyelid is accommodated by the kinetic achievement for each eyelid. The current work utilised both histological and anatomical methods to explore the eyelid's structural association with their kinetic, utilising the hoopoe and cattle egret as natural models. The third lid moved only without implicating other lids. Wrinkles on the edge of the hoopoe's eyelid became less pronounced during the opening phase, in contrast to, the edge of the egret's eyelid. The elevator muscle was visible only in the hoopoe, while both birds possessed the retractor anguli oculi muscles. The two later muscles collaborate with the depressor muscle during the closure phase. Two types of collagen I and III were detected within the stroma of the eyelids of both bird species; the elastic fibres was observed; few were in the hoopoe's eyelids. The eyelid edge of the hoopoe has more of the elastic fibres than those in its eyelid skin. The hoopoe's eyelid's epithelial layers contained more cytokeratin (AE1/AE3) than the egret. In conclusion, the anatomical traits of the hoopoe eyelids contribute to its greater motion compared to the egret eyelids.

FRESH extrusion 3D printing of type-1 collagen hydrogels photocrosslinked using ruthenium.

The extrusion bioprinting of collagen material has many applications relevant to tissue engineering and regenerative medicine. Freeform Reversible Embedding of Suspended Hydrogels (FRESH) technology is capable of 3D printing collagen material with the specifications and details needed for precise tissue guidance, a crucial requirement for effective tissue repair. While FRESH has shown repeated success and reliability for extrusion printing, the mechanical properties of completed collagen prints can be improved further by post-print crosslinking methodologies. Photoinitiator-based crosslinking methods are simple and have proven effective in strengthening protein-based materials. The ruthenium and sodium persulfate photoinitiator system (Ru(bpy)3/SPS) has been suggested as an effective crosslinking method for collagen materials. Herein, we describe the procedure our group has developed to combine extrusion-based 3D printing of type-1 collagen using FRESH technology with Ru(bpy)3/SPS photoinitiated crosslinking methods to improve the strength and stability of 3D printed collagen structures. Mechanical testing and cell biocompatibility assessments were performed to investigate the impact of Ru(bpy)3/SPS photoinitiated crosslinking and highlight the potential limitations of this method. These results demonstrate a significant improvement in the compressive strength of type-1 collagen samples as the Ru(bpy)3/SPS concentration increases. Additionally, type-1 collagen samples crosslinked with up to 1/10 mM Ru(bpy)3/SPS support PC12 cell viability over a period of 7 days. The primary limitations that were observed and described in detail in this protocol are: the FRESH slurry preparation, printing environment, extrusion printer hardware, and quality of the ruthenium reagent.

Association between ESR1 and COL1A1 gene polymorphisms and skeletal fluorosis in Tibetan, Kazakh, Mongolian and Russian populations, China.

Skeletal fluorosis is a chronic metabolic bone disease caused by excessive accumulation of fluoride in the bones. Previous studies have found that when the intake of tea fluoride is similar, the prevalence of skeletal fluorosis varies greatly among different ethnic groups, which may be related to different genetic backgrounds. Single nucleotide polymorphisms (SNPs) of estrogen receptor 1 (ESR1) and collagen type 1 α1 (COL1A1) were strongly associated with bone metabolism as well as bone growth and development, but their association with the risk of skeletal fluorosis has not been reported. To explore the incidence of skeletal fluorosis in different nationalities in the endemic fluorosis area of brick-tea type. To study the relationship between 4 SNPS of ESR1 and COL1A1 gene and skeletal fluorosis METHODS: A cross-sectional study was conducted in Inner Mongolia, Qinghai and Xinjiang. By including exclusion criteria, a total of 989 people were included in the study, demographic data were collected, and physical examinations and laboratory biochemical tests were performed. The X-ray of the participants were diagnosed according to the diagnostic criteria of Chinese endemic skeletal fluorosis (WS192-2008). Fluoride levels in tea or urine were measured using fluoride ion electrodes. SNP was evaluated using Sequenom-MassARRAY system. The prevalence of skeletal fluorosis varies among different nationalities. Binary logistic regression found that carried the ESR1 Rs9340799 G allele played a protective role in brick-tea-type fluorosis (OR=0.673[95% CI, 0.495,0.914]). Russians carried the COL1A1 Rs1800012 T allele had a significantly higher risk of developing skeletal fluorosis (OR=6.370 [95% CI, 1.413,28.715]). When stratified by sex, carriage of the T allele in COL1A1 Rs1800012 significantly increased the risk of developing skeletal fluorosis in Russian men. At the same time, changes in tea fluoride intake and older age can affect the effect of genetic background differences on the risk of skeletal fluorosis. Our data suggested that there may be a genetic component to the risk of skeletal fluorosis in participants of different ethnicities and that this difference could modified by tea fluoride intake, sex or age.