Soluble Collagen Research Articles

Chemical Composition of Acid Soluble Collagen (ASC) Isolated from Indonesia Local “Kacang” Goat Skin (<i>Capra aegagrus hocus</i>)

Collagen from the local "Kacang” goat skin is a natural raw material in the halal food industry in Indonesia. This study aims to isolate acid-soluble collagen (ASC) from “Kacang” goat skin and characterize its chemical properties. The collagen was derived from one-year-old goat skin and cured in acid condition for 48 hours at 4°C to eliminate meats, fat, and hair. The cleaned skins were treated at 1:10 (w/v) of 0.1 M NaOH for 0, 24, and 48 h at 4°C. It was then neutralized in distilled water and extracted with 0.5 M acetic acid at a 1:10 (w/v) ratio for 24, 48, and 72 h at 4°C. The yield of ASC was 21%, characterized by chemical composition, soluble protein, differential scanning calorimeter (DSC), and protein molecular weight. The chemical composition of ASC was 11.15% (moisture), 9.04% (protein), 0.98% (fat), and 0.052% (ash). ASC has the highest collagen solubility in NaCl 5% at pH 2. ASC also has thermal stability with a low profile pattern of molecular weight. In conclusion, “Kacang” goat skin from Indonesia might be used to make a value-added product because it has a high moisture content and low fat level.

Changes in Texture and Collagen Properties of Pork Skin during Salt-Enzyme-Alkali Tenderization Treatment.

The effects of salt-enzyme-alkali progressive tenderization treatments on porcine cortical conformation and collagen properties were investigated, and their effectiveness and mechanisms were analyzed. The tenderization treatment comprised three treatment stages: CaCl2 (25 °C/0-30 min), papain (35 °C/30-78 min), and Na2CO3 (25 °C/78-120 min). The textural, microscopic, and collagenous properties (content, solubility, and structure) of pork skin were determined at the 0th, 30th, 60th, 90th, and 120th min of the treatment process. The results showed that the shear force, hardness, and chewability of the skin decreased significantly (p < 0.05), and the elasticity exhibited a gradual increase with the progression of tenderization. The content and solubility of collagen showed no significant change at the CaCl2 treatment stage. However, the soluble collagen content increased, the insoluble collagen content decreased, and the collagen solubility increased by 18.04% during the subsequent treatment with papain and Na2CO3. Meanwhile, the scanning electron microscopy results revealed that the regular, wavy structure of the pig skin collagen fibers gradually disappeared during the CaCl2 treatment stage, the overall structure revealed expansion, and the surface microscopic pores gradually increased during the papain and Na2CO3 treatment stages. The findings of the Fourier transform infrared spectroscopy analysis indicated that the hydrogen bonding interactions between the collagen molecules and the C=O, N-H and C-N bonds in the subunit structure of collagen were substantially altered during treatment and that the breakage of amino acid chains and reduction in structural ordering became more pronounced with prolonged treatment. In the tertiary structure, the maximum emission wavelength was blue-shifted and then red-shifted, and the fluorescence intensity was gradually weakened. The surface hydrophobicity was slowly increased. The salt-enzyme-alkali tenderization treatment considerably improved the physical properties and texture of edible pork skins by dissolving collagen fibers and destroying the structure of collagen and its interaction force.

Silver carp swim bladder collagen derived from deep eutectic solvents: Enhanced solubility against pH and NaCl stresses

Deep eutectic solvents (DESs) are renowned in chemical and food industries for their eco-friendly extraction efficacy. Silver carp swim bladders, a collagen-rich byproduct of surimi production, are underutilized, resulting in considerable protein waste. Traditionally, collagen extraction has relied on harsh acids, contributing to environmental pollution and producing collagens with limited solubility, thus constraining their applications. This study evaluated DESs compared to conventional acids in extracting collagen, focusing on structural and solubility variations. Notably, urea-based DESs (urea-lactic acid: U-LA, 1:10, w/v) achieved the highest hydroxyproline recovery rates (∼ 94 %), comparable to acetic acid (AA, 1:20, w/v), but with half the solid-liquid ratio. Unlike acid-extracted collagen, which preserved the triple-helical structure, urea-based DESs partially disrupted this configuration by reducing intramolecular hydrogen bonding within collagen. However, these solvents simultaneously increased intermolecular hydrogen bonding. This alteration significantly enhanced collagen's solubility, maintaining over 60 % across a broad pH range (1−10) and various NaCl concentrations (0–6 %, w/v). Furthermore, urea-acetic acid (U-AA) extracted collagen exhibited the highest maximum transition temperature (solid state, Tmax = 101.94 °C) and gel strength (165 g). The findings suggest that urea-based DESs not only enhance collagen recovery rates but also its solubility and gelation properties, broadening its potential applications in cosmetics, food products, and biomaterials.

Differential effects of macrophage subtype-specific cytokines on fibroblast proliferation and endothelial cell function in co-culture system.

Macrophages are involved in several critical activities associated with tissue repair and regeneration. Current approaches in regenerative medicine are focusing on leveraging the innate immune response to accelerate tissue regeneration and improve long-term healing outcomes. Of particular interest in this regard are the currently known, four main M2 macrophage subtypes: M2interleukin (IL)-4,IL-13, M2IC, M2IL-10, M2non-selective adenosine receptor agonists (NECA) (M2IL-4,IL-13 → M2NECA). In this study, rat bone marrow-derived macrophages (M0) were polarized to each of the four subtypes M2IL-4,IL-13 → M2NECA and cultured for 72 h in vitro. Luminex assay results highlighted increased production of tissue inhibitor of metalloproteinases-1 (TIMP-1) for M2IL-4,IL-13, higher amounts of transforming growth factor-beta 1 (TGF-β1) for M2IL-10, and elevated vascular endothelial growth factor A (VEGF-A) from M2NECA. Co-culture experiments performed with M2IL-10 macrophages and L929 fibroblasts highlighted the increased production of soluble collagen within the media as well as higher amounts of collagen in the extracellular matrix. Human umbilical vein endothelial cells (HUVECs) were co-cultured with M2NECA macrophages, which demonstrated an increase in intercellular adhesion molecule (ICAM) and platelet endothelial cell adhesion molecule (PECAM), as well as increased formation of endothelial tubes. The findings of this study emphasize a critical demand for further characterization and analyses of distinct M2 subtypes and careful selection of specific macrophage populations for regeneration of specific tissue types. The current, broad classification of "M2" may be sufficient in many general tissue engineering applications, but, as conditions are constantly in flux within the microenvironment in vivo, a higher degree of specificity and control over the initial M2 subtype could result in more consistent long-term outcomes where macrophages are utilized as part of an overall regenerative strategy.

Insights into the Structural and Thermal Properties of Pepsin-Soluble Collagen from Daggertooth pike conger (Muraenesox cinereus)

Pepsin soluble collagen (PSC) is a type-1 collagen which is abundant in skin. The pepsin soluble collagen was successfully extracted from the skin of Daggertooth pike conger (Muraenesox cinereus) by using the conventional method of salt precipitation followed by dialysis. Pepsin-soluble collagen showed a yield of 10.12% on wet matter basis and 25.5% on dry matter basis. The triple helical structure of collagen was confirmed by Fourier Transform Infrared Spectroscopy (FTIR) and UV-Visible spectrophotometry. Isolated PSC was confirmed as type 1 collagen by Sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE). FTIR spectra of PSC suggested that the secondary structure of the triple helical collagen was intact even after pepsin digestion. Pepsin-soluble collagen was soluble in acidic pH with maximum solubility at pH 4. The solubility was found to be decreased with an increase in the concentration of sodium chloride with a minimum solubility at 4%. The present PSC isolate from eel fish exhibited comparatively high thermal stability of 36 ͦ C. Morphological analysis by Scanning electron microscopy (SEM) revealed a porous structure and comparatively high thermal stability makes it a promising biomaterial.

Harnessing the Biomimetic Effect of Macromolecular Crowding in the Cell-Derived Model of Clubfoot Fibrosis.

Fibrotic changes in pediatric clubfoot provide an opportunity to improve corrective therapy and prevent relapses with targeted drugs. This study defines the parameters of clubfoot fibrosis and presents a unique analysis of a simple pseudo-3D in vitro model for disease-specific high-throughput drug screening experiments. The model combines clubfoot-derived fibroblasts with a biomimetic cultivation environment induced by the water-soluble polymers Ficoll and Polyvinylpyrrolidone, utilizing the principle of macromolecular crowding. We achieved higher conversion of soluble collagen into insoluble collagen, accelerated formation of the extracellular matrix layer and upregulated fibrosis-related genes in the mixed Ficoll environment. To test the model, we evaluated the effect of a potential antifibrotic drug, minoxidil, emphasizing collagen content and cross-linking. While the model amplified overall collagen deposition, minoxidil effectively blocked the expression of lysyl hydroxylases, which are responsible for the increased occurrence of specific collagen cross-linking in various fibrotic tissues. This limited the formation of collagen cross-link in both the model and control environments. Our findings provide a tool for expanding preclinical research for clubfoot and similar fibroproliferative conditions.

Consumer eating quality and physicochemical traits of pork Longissimus and Semimembranosus differed between genetic lines

Pork eating quality is affected by various factors. In this study, Longissimus thoracis et lumborum (LTL) and Semimembranosus (SM) muscles from seven genetic lines (PM-LR – Pure maternal, Landrace-type; PM-LW – Pure maternal, Large White-type; PM-D – Pure maternal, Duroc-type; PT-D – Pure terminal, Duroc-type; PT-LW – Pure terminal, Large White-type; PT-LR - Pure Terminal, Landrace-type; Comp-P × LW × D - Composite Terminal – Pietran × Large white × Duroc) were analyzed for pH, intramuscular fat (IMF) content, and collagen content and solubility. A consumer sensory test using check-all-that-apply (CATA) and biometric approaches was also conducted. The results showed that the IMF content of line PM-D was the highest (P = 0.004), while line PT-LW received the highest score in tenderness, liking of flavor, purchase intent, and quality grading (P < 0.05). Line PM-LR and PT-LR showed the lowest IMF content and were least preferred by consumers. Compared to LTL, SM showed higher pH, collagen solubility, and sensory scores in tenderness, juiciness, liking of flavor, and overall liking (P < 0.05). Different muscles and lines were associated with different CATA terms but not with differences in consumer emotional responses. pH positively influenced tenderness, juiciness, and overall liking (P < 0.05), but IMF and collagen had little effect. The flavor was the most important sensory attribute contributing to overall liking, followed by tenderness. Genetic line and muscle affected pork chemical properties and eating quality. The findings are important for the Australian pork industry to improve the eating quality of their products.

Abstract Tu088: Fibroblast Activation, Collagen Secretion, and Migration Occurs Independently of Has2 Expression

Background: Hyaluronan (HA) accumulates after tissue injury and may regulate the wound-healing process. We found that HA is increased in and around the scar following myocardial infarction (MI). Fibroblasts are the main producers of the collagen that comprises the scar, and we have shown that they are responsible for HA accumulation. Given that these two extraordinarily high-volume synthetic processes occur in the same place and simultaneously, we queried whether alterations in Has2 -dependent HA synthesis impacted collagen secretion and other fibroblast functions. Goal: To determine the impact of HA synthesis on fibroblast function. Methods and Results: We isolated cardiac fibroblasts from Has2 fl/fl mice and treated with Cre adenovirus to delete Has2 expression or Has2 adenovirus to overexpress Has2. We assessed cell number and found no differences when Has2 was deleted or overexpressed in both naïve fibroblasts (n=6); activation with TGF-b did not change this response . We used a scratch assay to assess migration and found no change between treatments in naïve fibroblasts (n=6). Hydroxyproline assessment of deposited collagen and immunoblotting for soluble collagen secretion in the media indicated no differences between treatments in naïve fibroblasts (n=3). Conclusion: Genetic manipulation of HA production did not impact proliferation, migration, or collagen secretion in fibroblasts. Considering the enormous metabolic requirement of fibroblasts to produce HA and collagen, these results suggest that the regulation of these processes may be distinct or that the substrate is not limiting in our experimental conditions. In the intact heart, substrate could become limiting and a relationship between these two biosynthetic processes may emerge

Effect of different temperature–time combinations on the quality and protein digestive properties of stewed beef tendons

This study investigated the effects of sous vide cooking and traditional high-temperature cooking on the texture, microstructure, protein structure and digestive properties of home made beef tendon using transmission electron microscopy, in vitro digestion and peptidomics. The adverse effects of heating on the muscle fiber structure and protein conformation of beef tendon gradually expanded with increasing temperature. In general, the degree of muscle fiber contraction, protein denaturation, and protein aggregation increases with temperature and time, with a concomitant decrease in protease action. The extent of protein digestion, and the yield of small fragments such as amino acids also decreased with increasing heating temperature and time. However, the solubilization of collagen makes the beef collagen more digestible after heating at 80°C, which indirectly leads to higher digestibility at 80°C. The combined peptide release and bioactive peptide results showed that the beef tendon heated at 60°C for 8 h produced the most peptides after digestion, and also produced four specific bioactive peptides, which were advantageous in terms of the number of digested products and bioactivity. The higher proportion of antioxidant amino acids in the product also gave the tendon heated at 60°C for 8 h a greater potential antioxidant capacity. As a result, beef tendon heated at 60°C for 8 h is more favorable for human digestion. This work may provide guidance for home cooking and dietary health.

Impact of Co-60 γ-ray irradiation on the cross-linking and stability of fish collagen: Structural changes and digestibility

Irradiation can promote the cross-linking of collagen to enhance its biological properties, but the molecular changes in irradiated collagen have few been investigated. This study aimed to explore the impact of irradiation treatment on the molecular structure stabilization and cross-linking degree of skin collagen. The results showed that collagen in solution was more susceptible to Co-60 gamma irradiation than that in fish skin and in sponge forms. The solubility of collagen in solution decreased by more than 80% and the carbonyl content increased by more than 4 times compared with the control group after 12 kGy irradiation. Spectroscopic analysis and sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE) showed that collagen in solution was cross-linked, especially at high irradiation doses. However, the triple helical structure of skin collagen and collagen sponge remained intact. Furthermore, irradiation also reduced the sensitivity of collagen to collagenase. Gastrointestinal digestion results showed that the antioxidant activity of collagen increased at 1–3 kGy doses and decreased at 9–12 kGy doses. Collagen irradiated at high doses (9–12 kGy) was more difficult to digest and had a larger average particle size. This study provides a potential new approach for the preparation of stable fishery-derived collagen with excellent antioxidant activity and resistance to digestion by irradiation treatment.

Liver Fibrosis: From Basic Science towards Clinical Progress, Focusing on the Central Role of Hepatic Stellate Cells.

The burden of chronic liver disease is globally increasing at an alarming rate. Chronic liver injury leads to liver inflammation and fibrosis (LF) as critical determinants of long-term outcomes such as cirrhosis, liver cancer, and mortality. LF is a wound-healing process characterized by excessive deposition of extracellular matrix (ECM) proteins due to the activation of hepatic stellate cells (HSCs). In the healthy liver, quiescent HSCs metabolize and store retinoids. Upon fibrogenic activation, quiescent HSCs transdifferentiate into myofibroblasts; lose their vitamin A; upregulate α-smooth muscle actin; and produce proinflammatory soluble mediators, collagens, and inhibitors of ECM degradation. Activated HSCs are the main effector cells during hepatic fibrogenesis. In addition, the accumulation and activation of profibrogenic macrophages in response to hepatocyte death play a critical role in the initiation of HSC activation and survival. The main source of myofibroblasts is resident HSCs. Activated HSCs migrate to the site of active fibrogenesis to initiate the formation of a fibrous scar. Single-cell technologies revealed that quiescent HSCs are highly homogenous, while activated HSCs/myofibroblasts are much more heterogeneous. The complex process of inflammation results from the response of various hepatic cells to hepatocellular death and inflammatory signals related to intrahepatic injury pathways or extrahepatic mediators. Inflammatory processes modulate fibrogenesis by activating HSCs and, in turn, drive immune mechanisms via cytokines and chemokines. Increasing evidence also suggests that cellular stress responses contribute to fibrogenesis. Recent data demonstrated that LF can revert even at advanced stages of cirrhosis if the underlying cause is eliminated, which inhibits the inflammatory and profibrogenic cells. However, despite numerous clinical studies on plausible drug candidates, an approved antifibrotic therapy still remains elusive. This state-of-the-art review presents cellular and molecular mechanisms involved in hepatic fibrogenesis and its resolution, as well as comprehensively discusses the drivers linking liver injury to chronic liver inflammation and LF.

The integrin receptor beta7 subunit mediates airway remodeling and hyperresponsiveness in allergen exposed mice

BackgroundFibroblast differentiation to a myofibroblast phenotype is a feature of airway remodeling in asthma. Lung fibroblasts express the integrin receptor α4β7 and fibronectin induces myofibroblast differentiation via this receptor.ObjectivesTo investigate the role of the β7 integrin receptor subunit and α4β7 integrin complex in airway remodeling and airway hyperresponsiveness (AHR) in a murine model of chronic allergen exposure.MethodsC57BL/6 wild type (WT) and β7 integrin null mice (β7 -/-) were sensitized (days 1,10) and challenged with ovalbumin (OVA) three times a week for one or 4 weeks. Similar experiments were performed with WT mice in the presence or absence of α4β7 blocking antibodies. Bronchoalveolar (BAL) cell counts, AHR, histological evaluation, soluble collagen content, Transforming growth factor-β (TGFβ) and Interleukin-13 (IL13) were measured. Phenotype of fibroblasts cultured from WT and β7 -/- saline (SAL) and OVA treated mice was evaluated.ResultsEosinophil numbers were similar in WT vs β7-/- mice. Prolonged OVA exposure in β7-/- mice was associated with reduced AHR, lung collagen content, peribronchial smooth muscle, lung tissue TGFβ and IL13 expression as compared to WT. Similar findings were observed in WT mice treated with α4β7 blocking antibodies. Fibroblast migration was enhanced in response to OVA in WT but not β7 -/- fibroblasts. α-SMA and fibronectin expression were reduced in β7-/- fibroblasts relative to WT.ConclusionsThe β7 integrin subunit and the α4β7 integrin complex modulate AHR and airway remodeling in a murine model of allergen exposure. This effect is, at least in part, explained by inhibition of fibroblast activation and is independent of eosinophilic inflammation.

Issues in the design of tissue-engineered collagen constructs and some approaches to their solution: A review

This review article analyzes modern literature sources on the design of bioinks and tissue-engineered constructs on the basis of soluble forms of collagen, including gelatin. The choice of soluble forms of collagen as a biopolymer basis for bioinks and this type of constructs is determined by their unique biocompatibility, bioresorbability, as well as the presence of adhesive sites (motifs) for binding cells with their subsequent proliferation and organ or tissue maturation. However, the poor mechanical properties of products derived from soluble collagens, rapid biodegradation, tendency to lose the solubility of highly viscous solutions when stored or with pH increase limit their application in tissue engineering. The use of more stable low-viscosity collagen solutions does not enable the creation of dimensionally stable tissue-engineered constructs. It is shown that the introduction of various water-soluble biocompatible polymeric additives into hydrogels on the basis of soluble collagens allows the above-mentioned problems to be solved, as well as providing a means to customize the required characteristics of bioinks and tissue-engineered constructs. The additives that improve their characteristics include biopolymers: silk sericin and fibroin, as well as alginates and fibrinogen, which can form cross-links in the presence of Ca2+. This type of crosslinking is shown to further improve the performance of these constructs. All of these biopolymers are commercially available. The article comparatively analyzes approaches to stabilizing the shape, improving the mechanical properties, and adjusting the bioresorption time of 3D printed tissue-engineered constructs during organ or tissue maturation.

Acid-soluble collagen (ASC) hydrolysate from Javanese goat (Capra aegagrus hocus) skin: effect of pepsin hydrolysis and antioxidant activity

Abstract Javanese goat (Capra aegagrus hocus) is an animal species which have many populations in Indonesia and it is used because more selective in feed, especially Leguminosae and seeds which of rich in collagen. The study aims to determine the impact of hydrolysis time and antioxidant activities on the extraction of skin Javanese goats using the acid-soluble collagen (ASC) method. The ASC used in this investigation was taken from another study and hydrolyzed with pepsin throughout the course of 0, 30, 60, 90, and 120 minutes of incubation. The success of the hydrolysis process can be shown by the percent degree of hydrolysis. Methods are used to determine the percent degree of hydrolysis of the TCA method. Results showed that hydrolyzing for 60 min yields the highest total soluble collagen of ASC, with a value of 0.77 mg/ml. Finally, the ASC which is hydrolysis use pepsin for 60 min has a degree of hydrolysis, and total soluble collagen is the highest. The protein molecular weight of ASC which is the hydrolysis of 60 min is smaller than before hydrolysis and it has radical scavenging activity of 56.42% ± 1.45. So far, ASC from Javanese goat (Capra aegagrus hocus) has been hydrolyzed in this study has high antioxidant activity and can be recommended as a substitute for functional food.

Optimizing tenderness of M. Semitendinosus steak for elderly people with the combination of ficin and sous-vide cooking

This study aimed to evaluate the sous-vide cooking and ficin treatment effects on the tenderness of beef steak and optimize it for the elderly using response surface methodology (RSM). The M. semitendinosus (ST) from Chikso cattle was shaped into 5 × 5 × 2.54 cm pieces. Ficin solution was injected into the ST steak at 10% of the meat weight, and sous-vide cooked in a water bath at 65 °C for 6 or 12 h. As ficin concentration increased, L*- and a*-value, shear force, and hardness decreased, while soluble peptides increased (P < 0.05). As cooking time increased, cooking loss and collagen solubility of the steak increased (P < 0.05). An interaction effect between ficin and sous-vide cooking was found in L*- and a*-value, shear force, hardness, and soluble peptides (P < 0.05). A model to optimize the hardness for elderly people was established (R2 = 0.7991). Optimization conditions by RSM were 0.86 U/L with 8.87 h (23 N/cm3) for tooth intake (grade 1), 16.31 U/L with 13.24 h (3 N/cm3) for gums intake (grade 2), according to KS H 4897 and Universal Design Foods concept for the elderly. These optimized conditions enable the production of customized products tailored to the oral conditions of elderly people.

Physiological platelet aggregation assay to mitigate drug-induced thrombocytopenia using a microphysiological system

Developing a reliable method to predict thrombocytopenia is imperative in drug discovery. Here, we establish an assay using a microphysiological system (MPS) to recapitulate the in-vivo mechanisms of platelet aggregation and adhesion. This assay highlights the role of shear stress on platelet aggregation and their interactions with vascular endothelial cells. Platelet aggregation induced by soluble collagen was detected under agitated, but not static, conditions using a plate shaker and gravity-driven flow using MPS. Notably, aggregates adhered on vascular endothelial cells under gravity-driven flow in the MPS, and this incident increased in a concentration-dependent manner. Upon comparing the soluble collagen-induced aggregation activity in platelet-rich plasma (PRP) and whole blood, remarkable platelet aggregate formation was observed at concentrations of 30 µg/mL and 3 µg/mL in PRP and whole blood, respectively. Moreover, ODN2395, an oligonucleotide, induced platelet aggregation and adhesion to vascular endothelial cells. SYK inhibition, which mediated thrombogenic activity via glycoprotein VI on platelets, ameliorated platelet aggregation in the system, demonstrating that the mechanism of platelet aggregation was induced by soluble collagen and oligonucleotide. Our evaluation system partially recapitulated the aggregation mechanisms in blood vessels and can contribute to the discovery of safe drugs to mitigate the risk of thrombocytopenia.

Dietary cottonseed protein concentrate affected the flesh texture and myofiber characteristics of large yellow croaker Larimichthys crocea

The effects of replacing dietary fishmeal with cottonseed protein concentrate (CPC) on the muscle texture and water holding capacity of large yellow croaker Larimichthys crocea were investigated after a 90-day feeding trial. Results showed that the complete substitution of dietary fishmeal with CPC resulted in a significant reduction in muscle drip loss by decreasing collagen content and increasing heat soluble collagen content, without affecting the texture. Moreover, reduced drip loss is contingent upon diminished muscle salt-soluble protein content by enhancing skeletal muscle degradation (ubiquitin-proteasome system, calpain proteases and lysosomal cathepsins) and decreasing energy levels. In conclusion, the substitution of 30% dietary fishmeal with CPC (i.e., 20.94% of CPC in diet) did not show any significant alterations in muscle quality of large yellow croaker. The complete replacement of dietary fishmeal with CPC (i.e., 69.80% of CPC in diet) reduced the water holding capacity of muscle.

Zinc Iodide Dimethyl Sulfoxide Reduces Collagen Deposition by Increased Matrix Metalloproteinase-2 Expression and Activity in Lung Fibroblasts.

Chronic inflammatory lung diseases are characterized by disease-specific extracellular matrix accumulation resulting from an imbalance of matrix metalloproteinases (MMPs) and their inhibitors. Zinc is essential for the function of MMPs, and zinc deficiency has been associated with enhanced tissue remodeling. This study assessed if zinc iodide (ZnI) supplementation through dimethyl sulfoxide (DMSO) modifies the action of MMPs in isolated human lung fibroblasts. The expression and activity of two gelatinases, MMP-2 and MMP-9, were determined by gelatin zymography and enzyme-linked immuno-sorbent assay (ELISA). Collagen degradation was determined by cell-based ELISAs. Collagen type I and fibronectin deposition was stimulated by human recombinant tumor growth factor β1 (TGF-β1). Untreated fibroblasts secreted MMP-2 but only minute amounts of MMP-9. TGF-β1 (5 ng/mL) reduced MMP-2 secretion, but stimulated collagen type I and fibronectin deposition. All the effects of TGF-β1 were significantly reduced in cells treated with ZnI-DMSO over 24 h, while ZnI and DMSO alone had a lower reducing effect. ZnI-DMSO alone did not increase MMP secretion but enhanced the ratio of active to inactive of MMP-2. ZnI alone had a lower enhancing effect than ZnI-DMSO on MMP activity. Furthermore, MMP-2 activity was increased by ZnI-DMSO and ZnI in the absence of cells. Soluble collagen type I increased in the medium of ZnI-DMSO- and ZnI-treated cells. Blocking MMP activity counteracted all the effects of ZnI-DMSO. Conclusion: The data suggest that the combination of ZnI with DMSO reduces fibrotic processes by increasing the degradation of collagen type I by up-regulating the activity of gelatinases. Thus, the combination of ZnI with DMSO might be considered for treatment of fibrotic disorders of the lung. DMSO supported the beneficial effects of ZnI.

Effects of gender and slaughter age on physicochemical and quality traits of Korean Hanwoo striploin.

Hanwoo beef is in high demand because of its unique flavor, freshness, and high-fat content. However, the longer rearing period required to enhance marbling in Hanwoo cattle has adverse environmental consequences, such as greenhouse gas emissions and overall rearing costs. To address consumer preferences for leaner and healthier meat, the Korean meat industry has recently introduced Hanwoo heifer meat as an alternative source, but its quality traits are still unclear. Nevertheless, there is a limited body of research exploring the impact of Hanwoo gender (steer, heifer, and cow) and their corresponding slaughter ages on meat quality traits. This study looked into how gender affected the physicochemical and qualitative features of Hanwoo striploin at their respective slaughter ages. Results revealed that cow striploin has higher levels of moisture (66.81%) and protein (20.76%), whereas it contains lower levels of fat (10.66%) and cholesterol (34.66 mg/100 g). Regarding the physicochemical properties, cow striploin exhibited significantly lower shear force, color indexes, and soluble collagen (p < 0.05). However, chondroitin (1.19%) and muscle fiber area (1,545.23 μm2) were significantly higher in steer striploin than in heifer and cow (p < 0.05). Cow striploin exhibited significantly higher levels of oleic acid, unsaturated fatty acids (UFAs), and monounsaturated fatty acids (MUFAs) while having lower levels of eicosadienoic acid and atherogenic index compared to the other two groups. Cows and heifers had higher concentrations of amino acid metabolites than striploin from steers. Furthermore, bioactive metabolites such as carnitine and carnosine content were found higher in cow and heifer respectively. Overall, Hanwoo cattle gender influences the qualitative attributes of striploin; nevertheless, compared to steer and heifer striploin, cow striploin is a relatively good source of protein, fatty acid content, and metabolites conducive to a healthy diet.

Procollagen-lysine 2-oxoglutarate 5-dioxygenase 2 promotes collagen cross-linking and ECM stiffening to induce liver fibrosis

Procollagen-lysine 2-oxoglutarate 5-dioxygenase 2 (Plod2) is a key collagen lysyl hydroxylase mediating the formation of collagen fiber and stabilized collagen cross-links, and has been identified in several forms of fibrosis. However, the potential role and regulatory mechanism of Plod2 in liver fibrosis remain unclear yet. Mouse liver fibrosis models were induced by injecting carbon tetrachloride (CCl4) intraperitoneally. The morphology and alignment of collagen was observed under transmission and scanning electron microscopy, and extracellular matrix (ECM) stiffness was measured by atomic force microscopy. Large amounts of densely packed fibrillar collagen fibers produced by myofibroblasts (MFs) were deposited in fibrotic liver of mice reaching very large diameters in the cross section, accompanied with ECM stiffening, which was positively correlated with collagen-crosslinking. The expression of Plod2 was dynamically up-regulated in fibrotic liver of mouse and human. In MFs transfection of Plod2 siRNA made collagen fibers more orderly and linear aligned which can be easily degraded and protected from ECM stiffness. Administration of Plod2 siRNA preventatively or therapeutically in CCl4 mice reduced the average size of collagen bundles in transverse section, increased collagen solubility, decreases the levels of crosslinking products hydroxylysylpyridinoline and lysylpyridinoline, prevented ECM stiffening and alleviated liver fibrosis. Altogether, Plod2 mediates the formation of stabilized profibrotic collagen cross-links in MFs, leading to the alteration of collagen solubility and ECM stiffness, and eventually aggravates liver fibrosis, which provide potential target for the treatment of liver disease.