Soluble Collagen Research Articles

A Prospective, Randomized, Double-Blind, Vehicle-Controlled Study Evaluating the Efficacy, Safety, and Patient Satisfaction of Tretinoin 0.05% Lotion for Chest Rejuvenation.

There is increasing interest in non-invasive options for chest rejuvenation with minimal to no downtime. Topical retinoids have long been used to correct photoaging due to their ability to promote epidermal hyperplasia, matrix metalloproteinase inhibition, collagen synthesis, and dispersion of melanin granules. Topical retinoid use is often limited by the ensuing irritation that occurs with initial use and resolves after about one month. Vehicle of delivery is a key factor to consider in order to minimize irritation and increase patient satisfaction. Micronized tretinoin 0.05% suspended in a polymer emulsion of hydrating ingredients (sodium hyaluronate, soluble collagen, and glycerin) is designed to aid in reducing irritation while ensuring uniform drug delivery. The primary objective of our study is to evaluate the safety, efficacy, and patient satisfaction of tretinoin 0.05% lotion for nonprocedural photorejuvenation of the chest. A total of 29 patients completed the trial, average age of 54.42 years (37-66 years old), Fitzpatrick II-IV skin types. Both the active and vehicle groups showed 30-40% improvement at day 180 according to the blinded evaluator mean percent improvement. Investigator global aesthetic improvement scale also trended towards improvement in both groups, with most patients exhibiting "improvement." Both the active and vehicle groups showed a significant change over time according to the nine-point photodamage and wrinkling scale, P<0.001 and P=0.007 (single factor ANOVA), respectively. The Fabi Bolton Wrinkle Scale also demonstrated improvement from screening to day 180; however, there was no statistical significance at any time point. At day 90, the active group had statistically significantly more erythema than the vehicle group (P<0.001), although both groups were only mild. At day 180, erythema decreased in both groups with the active group being similar to the vehicle group, 0.50±0.73 versus 0.09±0.30, respectively. Subjects in both the active and vehicle groups were equally satisfied at day 180, (2.38±1.15 in the active group versus 2.30±1.16 in the treatment group), with most subjects feeling "satisfied" with their results by day 180. This was also reflected in the subject global aesthetic improvement scale with most subjects noting noticeable improvement in the appearance of their chest from day 30 to day 180. Tretinoin 0.05% lotion delivered in a proprietary blend of hydrating ingredients offers a safe and efficacious option that has minimal downtime for patients seeking non-procedural photo-rejuvenation of the chest. The proprietary vehicle, containing hyaluronic acid, glycerin, and collagen, was crucial in minimizing irritation and producing at least a one-point improvement according to the 9 point photodamage scale and 30-40% improvement in photodamage as noted by the blinded evaluator percent improvement score in both the vehicle and active groups. J Drugs Dermatol. 2022;21(6):645-652. doi:10.36849/JDD.6658.

Content and Solubility of Collagen and Their Relation to Proximate Composition and Shear Force of Meat from Different Anatomical Location in Carcass of European Beaver (Castor fiber).

The content and solubility of collagen in the muscle tissue and cooked meat from three anatomical locations (loin, hind leg and shoulder) in carcasses of adult male European beavers and relationships of collagen fractions with proximate composition and shear force were studied. Shoulder muscle tissue contained the highest amount of intramuscular fat, collagen/protein ratio, total and insoluble collagen, and the lowest percentage of soluble collagen. The cooked meat from hind leg contained the lowest amount of total, soluble and insoluble collagen. The percentage of collagen fractions in cooked meat was comparable in all cuts (p > 0.05). The toughest meat was from the shoulder, followed by the hind leg, and the tenderest meat was from the loin (p < 0.01). Shear force of cooked meat was correlated positively with the amount of total collagen, insoluble collagen and its percentage in muscle tissue (0.597, 0.594 and 0.499, p < 0.01), as well as negatively with percentage of soluble collagen (−0.594, p < 0.001). No correlations between the shear force and the content of total collagen and its fractions in cooked meat were found. In conclusion, our results indicate that the amount of total collagen and its fractions in raw muscle tissue of beaver is a better tenderness predictor for cooked meat than their values in heat-treated meat.

Multi-pin contact drawing enables production of anisotropic collagen fiber substrates for alignment of fibroblasts and monocytes

Type I collagen is the most abundant protein in the human body and is known to play important roles in numerous biological processes including tissue morphogenesis and wound healing. As such, it is one of the most frequently used substrates for cell culture, and there have been considerable efforts to develop collagen-based cell culture substrates that mimic the structural organization of collagen as it is found in native tissues, i.e., collagen fibers. However, producing collagen fibers from extracted collagen has been notoriously difficult, with existing methods providing only low throughput production of collagen fibers. In this study, we prepared collagen fibers using a highly efficient, bio-friendly, and cost-effective approach termed contact drawing, which uses an entangled polymer fluid to aid in fiber formation. Contact drawing technology has been demonstrated previously for collagen using highly concentrated dextran solutions with low concentrations of collagen. Here, we show that by replacing dextran with polyethylene oxide (PEO), high collagen content fibers may be readily formed from mixtures of soluble collagen and PEO, a polymer that readily forms fibers by contact drawing at concentrations as low as 0.5%wt. The presence of collagen and the formation of well-ordered collagen structures in the resulting fibers were characterized by attenuated total reflectance Fourier-transform infrared spectromicroscopy, Raman spectromicroscopy, and fluorescence microscopy. Corresponding to well-ordered collagen, the mechanical properties of the PEO-collagen fibers approximated those observed for native collagen fibers. Growth of cells on aligned PEO-collagen fibers attached to a polydimethyl siloxane support was examined for human dermal fibroblast (WS1) and human peripheral leukemia blood monocyte (THP-1) cell lines. WS1 and THP-1 cells readily attached, displayed alignment through migration and spreading, and proliferated on the collagen fiber substrate over the course of several days. We also demonstrated the retrieval of viable cells from the PEO-collagen fiber substrates through enzymatic digestion of the collagen substrate with collagenase IV.

Porous carbon sponges from collagen-rich biomass waste for high-performance supercapacitors

This study reports the utilisation of degradable biomass to create high-value porous carbon materials with excellent energy storage properties. We explore the extraction of soluble collagen from chicken feet using a sustainable and cost-effective method and its conversion to collagen sponges with interconnected porous features. In this study, we developed unique graphene integrated 3D porous carbon sponges from chicken feet derived collagen for the first time. We have also investigated graphene integrated porous carbon's (C-G-collagen) surface, chemical, thermal, and electrochemical properties. The unique porous structure of C-G-collagen provides a large surface area of 1087 m2/g and improved electrochemical performance with a high capacitance of 365 F/g at 1 mV/s. The as-fabricated electrode material possesses constant cyclic stability even after 10,000 cycles at 100 mV/s. This study confirmed that chicken-feet-derived porous carbon sponges are a viable option to fabricate the highly porous structures with large surface areas, and unique electronic and chemical properties. These porous carbon sponges can be used in energy storage applications, thereby demonstrating a unique pathway for developing functional materials suitable for a wide range of multifunctional applications.

Skin-Whitening and Antiwrinkle Proprieties of Maackia amurensis Methanolic Extract Lead Compounds

(1) Background: This study aimed to investigate the feasibility of using Maackia amurensis branch extract as a cosmetic ingredient with skin-whitening and antiwrinkle effects. (2) Methods: The skin-whitening effect of M. amurensis branch extract was confirmed by investigating α-melanocyte-stimulating hormone (α-MSH)-induced melanin synthesis and melanogenic protein expression in B16F1 cells. The antiwrinkle effect of M. amurensis branch extract was verified by assessing matrix metalloproteinase (MMP)-1 expression and soluble collagen content in CCD-986sk cells. The major compounds in M. amurensis branch extract were identified through isolation and characterization and confirmed by high-performance liquid chromatography analysis. (3) Results: M. amurensis branch extract significantly inhibited α-MSH-induced melanin synthesis by 49%, 42%, and 18% at 50, 37.5, and 25 μg/mL concentrations, respectively, compared with the negative control (NC). M. amurensis branch extract also significantly reduced the expression of the microphthalmia-associated transcription factor, tyrosinase-related protein (TRP)-1, TRP-2, and tyrosinase in B16F1 cells. Furthermore, M. amurensis branch extracts decreased ultraviolet A-induced MMP-1 expression and increased soluble collagen synthesis in CCD-986sk cells. In addition, the major compounds present in M. amurensis branch extract were found to be formononetin, genistein, trans-resveratrol, piceatannol, and tectoridin. (4) Conclusions: M. amurensis branch extract has skin-whitening and antiwrinkle properties. Therefore, it can be used as an ingredient in functional cosmetics with skin-whitening and antiwrinkle effects.

Impact of Factors Secreted by Tumor Cells on Response of Pleural Mesothelial Cells to Different Sclerosing Agents in an In Vitro Model.

BackgroundChemical pleurodesis is one of the major therapeutic options for patients with recurrent malignant pleural effusion. Mesothelial cells are considered to play a pivotal role in the response to different chemical compounds (sclerosants) used for pleurodesis. Malignant cells might have an impact on the mesothelial response to applied sclerosing agents and, in consequence, on the efficacy of pleurodesis. We aimed to evaluate the impact of cancer cell paracrine on mesothelial cell response to different sclerosing agents.Material/MethodsThe study used mesothelial cell (MeT-5A) cultures stimulated with sclerosing agents (talc, doxycycline, iodopovidone, and TGF-β for 24 h) in the presence or absence of supernatants from adenocarcinoma cultures (HCC827). The mesothelial mRNA expression and protein levels of IL-6, IL-8, and TGF-β was assessed. Further, lung fibroblasts were cultured with and without cell supernatants from previously established cell cultures for 24 h. Then, concentration of soluble collagen was evaluated in culture supernatants.ResultsThe exposure of mesothelial cells to sclerosants decreased the concentration of IL-6 and IL-8 protein. The addition of mediators secreted by adenocarcinoma altered the inflammatory response of the mesothelial cells to sclerosing agents. IL-8 concentration in cultures stimulated with talc and adenocarcinoma supernatant was higher compared to cultures stimulated with talc only. The exposure of lung fibroblasts to supernatant from mesothelial cell (with or without adenocarcinoma) did not affect collagen secretion.ConclusionsAn addition of soluble factors produced by adenocarcinoma altered the inflammatory response of the pleural mesothelial cells after stimulation with sclerosing agents. Our observations suggest that the tumor paracrine effect affects biological pathways of pleurodesis.

Development and in vitro investigation of a biodegradable mesh for the treatment of stress urinary incontinence

Introduction and hypothesisThe use of polypropylene (PP) mesh for stress urinary incontinence (SUI) surgery has declined because of safety concerns. The aim of this study is to evaluate a biodegradable polycaprolactone (PCL) mesh and a PCL composite mesh tissue engineered with human uterine fibroblasts (HUFs) for SUI surgery by comparing mechanical properties and in vitro biocompatibility to commercially available PP and porcine dermis (PD).MethodsThe mechanical properties of four scaffold materials were evaluated: PCL, PCL-collagen-hyaluronic acid composite, acellular porcine dermal collagen (PD) (Pelvicol™) and polypropylene (Gynecare TVT™ Exact®). HUFs were seeded on separate scaffolds. After 7 and 14 days scaffolds were assessed for metabolic activity and cell proliferation using Alamar Blue, Live/Dead and PicoGreen assays. Soluble collagen production was evaluated using a Sircol assay.ResultsPCL and the composite scaffold reached ultimate tensile strength (UTS) values closest to healthy pelvic floor tissue (PCL = 1.19 MPa; composite = 1.13 MPa; pelvic floor = 0.79 MPa; Lei et al. Int Urogynecol J Pelvic Floor Dysfunct. 18(6):603-7, 2007). Cells on PCL showed significantly greater cell viability than PP at day 7 (p < 0.0001). At D14 the composite scaffold showed significantly greater cell viability than PP (p = 0.0006). PCL was the best performing scaffold for soluble collagen production at day 14 (106.1 μg versus 13.04 μg for PP, p = 0.0173).ConclusionsWe have designed a biodegradable PCL mesh and a composite mesh which demonstrate better biocompatibility than PP and mechanical properties closer to that of healthy pelvic floor tissue. This in vitro study provides promising evidence that these two implants should be evaluated in animal and human trials.

Tumbling and subsequent aging improves tenderness of beef longissimus lumborum and semitendinosus steaks by disrupting myofibrillar structure and enhancing proteolysis.

Tenderness is an important sensory attribute to the overall eating experience of beef. Identifying novel methods to ensure consistent tenderness, especially in inherently tough cuts, is critical for the industry. This study investigated if tumbling without brine inclusion could be an effective method to improve the quality and palatability attributes of beef longissimus lumborum (LL) and semitendinosus (ST) steaks. Furthermore, interactions with postmortem aging were evaluated to determine how tumbling might affect protein degradation and muscle ultrastructure. At 5 d postmortem, pairs of LL and ST muscles from beef carcasses (n = 16) were bisected, vacuum packaged, and tumbled for 0, 40, 80, or 120min. Sections were divided and subsequently aged an additional 0 or 10 d at 2 °C. Tumbling for any duration improved instrumental tenderness of LL (P < 0.001) but not ST (P > 0.05) steaks, regardless of aging time. Tumbling exacerbated moisture loss in both muscles shown by greater purge and cooking losses (P < 0.05). Myofibrillar fragmentation was induced through tumbling in both muscles (P < 0.001), which was supported by transmission electron microscopy images. Tumbling for 120min followed by 10 d of aging resulted in less abundant intact troponin-T in both LL and ST (P < 0.05), as well as less intact desmin in ST (P < 0.05); however, calpain-1 autolysis was not affected by tumbling (P > 0.05). No effects of tumbling, aging, nor the interaction were found for the content and solubility of collagen (P > 0.05). Consumer panelists (n = 120/muscle) rated LL steaks tumbled for any duration higher for tenderness and overall liking compared to control steaks (P < 0.05). For ST, significant interactions were found for consumer liking of tenderness and juiciness. In general, tumbling without subsequent aging resulted in poorer juiciness than non-tumbled (P < 0.05), while at 10 d no differences in juiciness were found between treatments (P > 0.05). For ST steaks that were aged 10 d, 120min of tumbling resulted in greater tenderness liking than non-tumbled steaks (P < 0.05). These results suggest that tumbling would result in myofibrillar fragmentation and may benefit the degradation of myofibrillar proteins; however, there would be negligible impacts on collagen. Accordingly, tumbling without brine inclusion alone may be sufficient to improve tenderness and overall liking of LL steaks, while combined tumbling with subsequent postmortem aging would be necessary to improve tenderness liking of ST.

ENAMPT Is a Novel Damage-associated Molecular Pattern Protein That Contributes to the Severity of Radiation-induced Lung Fibrosis.

The paucity of therapeutic strategies to reduce the severity of radiation-induced lung fibrosis (RILF), a life-threatening complication of intended or accidental ionizing radiation exposure, is a serious unmet need. We evaluated the contribution of eNAMPT (extracellular nicotinamide phosphoribosyltransferase), a damage-associated molecular pattern (DAMP) protein and TLR4 (Toll-like receptor 4) ligand, to the severity of whole-thorax lung irradiation (WTLI)-induced RILF. Wild-type (WT) and Nampt+/- heterozygous C57BL6 mice and nonhuman primates (NHPs, Macaca mulatta) were exposed to a single WTLI dose (9.8 or 10.7 Gy for NHPs, 20 Gy for mice). WT mice received IgG1 (control) or an eNAMPT-neutralizing polyclonal or monoclonal antibody (mAb) intraperitoneally 4 hours after WTLI and weekly thereafter. At 8-12 weeks after WTLI, NAMPT expression was assessed by immunohistochemistry, biochemistry, and plasma biomarker studies. RILF severity was determined by BAL protein/cells, hematoxylin and eosin, and trichrome blue staining and soluble collagen assays. RNA sequencing and bioinformatic analyses identified differentially expressed lung tissue genes/pathways. NAMPT lung tissue expression was increased in both WTLI-exposed WT mice and NHPs. Nampt+/- mice and eNAMPT polyclonal antibody/mAb-treated mice exhibited significantly attenuated WTLI-mediated lung fibrosis with reduced: 1) NAMPT and trichrome blue staining; 2) dysregulated lung tissue expression of smooth muscle actin, p-SMAD2/p-SMAD1/5/9, TGF-β, TSP1 (thrombospondin-1), NOX4, IL-1β, and NRF2; 3) plasma eNAMPT and IL-1β concentrations; and 4) soluble collagen. Multiple WTLI-induced dysregulated differentially expressed lung tissue genes/pathways with known tissue fibrosis involvement were each rectified in mice receiving eNAMPT mAbs.The eNAMPT/TLR4 inflammatory network is essentially involved in radiation pathobiology, with eNAMPT neutralization an effective therapeutic strategy to reduce RILF severity.

Inhibition of CHIT1 as a novel therapeutic approach in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive and eventually fatal lung disease with a complex etiology. Approved drugs, nintedanib and pirfenidone, modify disease progression, but IPF remains incurable and there is an urgent need for new therapies. We identified chitotriosidase (CHIT1) as new driver of fibrosis in IPF and a novel therapeutic target. We demonstrate that CHIT1 activity and expression are significantly increased in serum (3-fold) and induced sputum (4-fold) from IPF patients. In the lungs CHIT1 is expressed in a distinct subpopulation of profibrotic, disease-specific macrophages, which are only present in patients with ILDs and CHIT1 is one of the defining markers of this fibrosis-associated gene cluster. To define CHIT1 role in fibrosis, we used the therapeutic protocol of the bleomycin-induced pulmonary fibrosis mouse model. We demonstrate that in the context of chitinase induction and the macrophage-specific expression of CHIT1, this model recapitulates lung fibrosis in ILDs. Genetic inactivation of Chit1 attenuated bleomycin-induced fibrosis (decreasing the Ashcroft scoring by 28%) and decreased expression of profibrotic factors in lung tissues. Pharmacological inhibition of chitinases by OATD-01 reduced fibrosis and soluble collagen concentration. OATD-01 exhibited anti-fibrotic activity comparable to pirfenidone resulting in the reduction of the Ashcroft score by 32% and 31%, respectively. These studies provide a preclinical proof-of-concept for the antifibrotic effects of OATD-01 and establish CHIT1 as a potential new therapeutic target for IPF.

Optimization of Valorization of Chicken MDCM to Produce Soluble Protein and Collagen Peptides

This study aimed to utilize enzymatic treatment and pressurized hot water extraction (PHWE) to recover soluble food-grade protein and collagen peptides from mechanically deboned chicken meat (MDCM), a side-stream from the meat industry. Food-grade enzyme blends Ermitase 1 and Ermitase 2 were used to fractionate the mechanically deboned meat into fat, soluble protein, and solids. Response surface methodology was utilized to optimize treatments to maximize the protein yield. At the optimum conditions (hydrolysis time 240 min, E:S 0.27%, and a hydromodule 1 L/kg), the enzymatic treatment produced high protein yield, approximately 90%. The protein hydrolysates showed a good solubility index, but weak gelling properties. The PHWE of the bones resulted in a high nitrogen yield, approximately 87%, at the optimum conditions of 190 °C and 83 min. Peptides in the bone extract were in the range of 0.5–13.7 kDa. Overall, our study highlights the importance of response surface methodology to optimize parameters for mechanically deboned chicken meat enzymatic and PHWE treatments to achieve high yields of protein for food applications and low-molecular-weight collagen peptides for cosmetic applications. The crucial role of protein and peptide prices was observed in preliminary profitability analysis.

Post-enzymatic hydrolysis heat treatment as an essential unit operation for collagen solubilization from poultry by-products

Enzymatic protein hydrolysis (EPH) is an invaluable process to increase the value of food processing by-products. In the current work the aim was to study the role of standard thermal inactivation in collagen solubilization during EPH of poultry by-products. Hundred and eighty hydrolysates were produced using two proteases (stem Bromelain and Endocut-02) and two collagen-rich poultry by-products (turkey tendons and carcasses). Thermal inactivation was performed with and without the sediment to study the effect of heat on collagen solubilization. A large difference in molecular weight distribution profiles was observed when comparing hydrolysate time series of the two proteases. In addition, it was shown that 15 min heat treatment, conventionally used for inactivating proteases, is essential in solubilizing collagen fragments, which significantly contributes to increasing the protein yield of the entire process. The study thus demonstrated the possibility of producing tailored products of different quality by exploiting standard heat inactivation in EPH.

Impact of APRF+ in Combination with Autogenous Fibroblasts on Release Growth Factors, Collagen, and Proliferation and Migration of Gingival Fibroblasts: An In Vitro Study.

The present study aimed to compare the action of advanced platelet-rich fibrin (A-PRF+) alone with the action of A-PRF+ combined with autologous gingival fibroblasts. The components released from A-PRF+ conditioned with autogenous fibroblasts that were quantified in the study were fibroblast growth factor (FGF), vascular endothelial growth factor (VEGF), trans-forming growth factor-beta1 and 2 (TGFβ1 and TGFβ2), and soluble collagen. A-PRF+ combined with fibroblasts demonstrated significantly higher values of released VEGF at every time point and, after 7 days, significantly higher values of released TGFβ2. A viability test after 72 h showed a significant increase in proliferation fibroblasts after exposition to the factors released from A-PRF+ combined with fibroblasts. Similarly, the degree of wound closure after 48 h was significantly higher for the factors released from A-RRF+ alone and the factors released from A-RRF+ combined with fibroblasts. These results imply that platelet-rich fibrin (PRF) enhanced with fibroblasts can be an alternative method of connective tissue transplantation.

P082 The profibrogenic role of neutrophil extracellular traps in stenotic Crohn’s disease: a new antifibrotic target?

Abstract Background Neutrophil extracellular traps (NETs) are structures constituted of DNA filaments and protein granules, extruded by neutrophils after various insults, such as chronic inflammation. Their formation is dependent on the citrullination of histone H3 (H3cit) in the nucleus by peptidylarginine deiminase 4 (PAD4). The pathogenic effect of NETs in Crohn’s disease (CD) has been poorly addressed so far. Recently, a profibrogenic role of NETs has been proposed in the lung. The aim of the present study was to assess whether NETs may trigger the fibrotic process in patients with CD. Methods Multiplex immunofluorescence (M-IF) for PAD4, myeloperoxidase, neutrophil elastase, H3cit, vimentin and alpha-SMA were performed in unaffected, inflamed and fibrotic ileum of patients operated for stricturing CD. From the same patients, primary intestinal fibroblasts (PIF) were cultured from unaffected ileum. NETs were obtained from healthy volunteers’ neutrophils, incubated with 50 nM phorbol myristate acetate for 3.5 hours. Subconfluent PIF were stimulated in vitro with NETs for 6 hours and RNA extracted for sequencing (RNAseq). Cell culture medium was collected for soluble collagen analysis, using SIRCOL®. Experiments were replicated in 5 patients. CCD-18Co cell line was used to test the migratory activity of fibroblasts with a scratch test and to confirm the expression of profibrogenic proteins, such as fibroblast activation protein (FAP) and collagen 3A1. M-IF was interpreted using computational analysis. Statistics was performed with Kruskal-Wallis Test for collagen quantification, with p &amp;lt; 0.05. For RNAseq, Poisson distribution and DESeq2 were used, with significance set at Q &amp;lt; 0.05; the resulting gene list was then analysed with ClueGo® software. Results M-IF showed that NETs were primarily found in inflamed areas, with clusters of these traps located close to intestinal myofibroblasts in the deeper submucosa layer (Figure 1). The gene ontology of RNAseq (Figure 2) showed significant upregulation of profibrogenic pathways of TGFB1/SMAD and p38/MAPK in the group of PIF co-cultured with NETs. NETs stimulation determined a higher release of collagen in the medium (p = 0.003), and an increase in the protein expression of FAP and collagen 3A1 in PIF. Accordingly, NETs profibrotic effect resulted also in a slower migratory ability of activated fibroblasts. Conclusion Our data show that NETs are produced during active inflammation of CD and their colocalisation with intestinal myofibroblasts suggests that they may represent an early trigger of fibroblast activation. Clinically, the inhibition of PAD4 might result in both contrasting inflammation and fibrogenesis. An in vivo chronic model of colitis on PAD4-KO mice is ongoing to confirm these findings.

Research Note: Quality parameters of turkey hens breast fillets detected in processing plant with deep pectoral myopathy and white striping anomaly

The increase in the consumption of poultry meat intensified production, which allowed the emergence of myopathies associated with broiler and turkey meat. The aim to examine possible quality alterations in the 240 Pectoralis major muscle (breast fillets) from carcasses of turkey breeder hens. Regarding DPM, 120 samples of breast fillets from turkey of the Nicholas strain with Pectoralis minor muscle together were selected according to the occurrence of the myopathy in the Pectoralis minor muscle (tender), as follows: DPM score 2 (n = 40), DPM score 3 (n = 40), and a control group unaffected by DPM, score 0 (n = 40). Then, different 120 samples, from the same flock of birds, were selected according to White Striping (WS) anomaly in the Pectoralis major muscle (breast fillets), considering the degree of severity of the striations apparent in the muscle, as follows: moderate (n = 40), severe (n = 40) and a control group (normal) without the presence of WS anomaly (n = 40), with set up as a completely randomized design with 3 treatments for DPM and WS. We evaluated in meat of turkey breeder hens color, water-holding capacity (WHC), cooking loss (CL), shear force (SF), sarcomere length (SL) and total, soluble and insoluble collagen contents. The color parameters lightness (L*), redness (a*), and yellowness (b*) of turkey breeder hens breast fillets were altered by the occurrence of DPM and WS and as except CL, there were a difference for WHC and SF (P < 0.05). Significant differences were observed for sarcomere length (P < 0.05) between fillets without myopathies and with DPM Score 2 and 3 too. Higher values of total collagen (%) were observed for the most severe category of involvement for both myopathies. The DPM and WS affect the color and in a partial reduction texture of the breast fillets meat of turkey breeder hens and this may have a negative economic impact on the meat industry, because these are the main points evaluated by the consumer, in the most value commercial cut.

Characteristics comparison of collagens from squid skin by different extraction methods

To provide a scientific basis for the comprehensive utilization of squid processing by-products, squid skin collagen was extracted by acid, enzyme and hot water, respectively, and the physicochemical characteristics of the collagens were compared. The results showed that the yield of acid soluble collagen (ASC), pepsin soluble collagen (PSC) and heat soluble collagen (HSC) was 7.41 ± 0.55%, 32.86 ± 0.67% and 42.23 ± 0.82% (dry weight basis), respectively. FTIR, UV and SDS-PAGE analysis suggested that ASC, PSC and HSC had the typical characteristics of type I collagen and retained the complete triple helix structure. The thermal stability of ASC was higher than that of PSC and HSC. ASC had a more uniform and compact porous network structure than PSC, while HSC was an irregular sheet structure. The solubility of HSC was obviously higher than that of ASC and PSC, and the effect of pH and NaCl on the solubility of HSC was inconspicuous in the experiment conditions. The extraction methods had significant effects on the structure and physicochemical properties of collagens. The solubility of HSC suggested that it was more suitable for liquid products. Moreover, the structural characteristics and high thermal stability of ASC made it suitable for biomedical materials and thermal processing products.

Effects of different soaking time and heating methods on the tenderness of mutton

In the process of heating the mutton, the length of the soaking time will affect the meat tenderness, and the proper change of the soaking time can improve the meat tenderness. The sample was treated by water bath and microwave heating method, and the cooking loss rate, collagen solubility, shear force and the like were used as indicators for measuring tenderness. The effect of different soaking time on the tenderness of mutton was studied under water bath and microwave heating. The prolonged incubation time, the total soluble protein, collagen solubility and cooking loss of the meat treated by water bath were significantly increased (P < 0.01); while the myofibrillar protein and shear force values showed a downward trend. The difference in soaking time has an effect on the meat tenderness. Extending the soaking time, the color of the 20 µ strip gradually deepened, and the 32 µ and 75 µ strips showed different degrees of weakening. This indicates that the protein is degraded and the myofiber structure of the meat is destroyed. This provides a theoretical basis for the production and processing of enterprises and the table culture of the people.

ST2 deletion accelerates inflammatory-angiogenesis and remodeling in subcutaneous implants in mice.

Implantation of biomedical/synthetic devices to replace and/or repair biological tissues very often induces an adverse healing response (scarce angiogenesis, excessive collagen deposition) which is detrimental to implant functionality and integration to host tissue. Interleukin-33/ST2 axis (IL-33/ST2) has been shown to modulate angiogenic and remodeling processes in several types of injuries. However, its effects on these processes after implantation of synthetic matrix have not been reported. Using synthetic matrix of polyether-polyurethane implanted subcutaneously in mice lacking ST2 receptor (ST2/KO), we characterized neovascularization and matrix remodeling in the fibrovascular tissue induced by the implants. Tissue accumulation was increased inside and around the implants in KO implants relative to the wild type (WT). More intense proliferative activity, using CDC 47 marker, was observed in KO implants compared with that of WT implants. Angiogenesis, using two endothelial cell markers, Von Willebrand Factor (VWF) and vascular endothelial cell VE cadherin and hemoglobin content, increased in implants of KO mice relative to control WT. Remodeling of the newly formed fibrovascular tissue (soluble collagen and PicroSirius Red-stained histological sections) showed predominance of type 1 collagen in ST2-KO implants versus type 3 in control implants. The number of positive cells for caspase-3, apoptotic marker, decreased in ST2 group. Our findings evidenced a role of IL-33/ST2 axis in restraining blood vessel formation and regulating the pattern of matrix remodeling in the fibrovascular tissue induced by synthetic implants. Intervention in this cytokine complex holds potential to accelerate integration of biomaterial and host tissue by improving blood supply and matrix remodeling.

Effects of different heating conditions on protein composition in each muscle type of yellowtail (Seriola quinqueradiata)

To clarify the factors influencing the physical properties of fish after heat treatments, we investigated changes in the properties of proteins in the dorsal ordinary and dark muscle of yellowtail (Seriola quinqueradiata) heated under different conditions commonly used for the purposes of food hygiene. High-temperature/short-time heating (85°C for 90 s and 75°C for 60 s) affected the protein solubility more than low-temperature/long-time heating (63°C for 30 min). Sodium dodecyl sulphate-polyacrylamide gel electrophoresis and differential scanning calorimetry showed that low-temperature/long-time heating reduced the degree of actin denaturation in fish compared with that by other heating conditions. In addition, collagen solubility was enhanced with low-temperature/long-time heating. Therefore, these results suggest that differences in the degree of actin and collagen denaturation are responsible for the enhanced meat tenderness and diminished meat shrinkage, resulting from low-temperature/ long-time heating.

Associação de fatores de produção e de morfometria muscular sobre a maciez da carne de frangos caipiras

ABSTRACT: This study assessed whether the meat tenderness of broilers raised in a free-range system varies by sex, lineage, and age at the time of slaughter. Physicochemical parameters were measured to adequately assess breast and thigh muscle morphometry, including shear force (SF), muscle fibre diameter (MD), histological connective tissue (HCT) content, and total and soluble collagen contents (TCC and SCC, respectively). The experiment was conducted with a completely randomized design using two lineages (Pescoço Pelado and Paraíso Pedrês), with specimens of both sexes raised in a free-range system. Randomly selected broilers were slaughtered at 65, 75, 85, and 95 days old. A total of 192 birds were analysed. SF values correlated positively with age. The highest SF values were measured in thighs of the Pescoço Pelado lineage. Age also showed a positive correlation with MD and HCT content of the breast regardless of lineage. Gender did not have any significant correlation with physical parameters; although, higher values were measured in thighs of the Paraíso Pedrês than in those of the Pescoço Pelado lineage. There were no significant differences among treatments regarding the SCC and TCC of thighs and breasts. Principal component analysis (PCA) revealed relationships between SF and the rest of the measured attributes. PCA showed that age was positively correlated with the SF, MD, and HCT content of thighs and breasts. In contrast, SCC and TCC had negative correlations. The greatest breast and thigh MD values were associated with the least tender meat. Thus, age at the time of slaughter proved to be the most significant parameter impacting the physical characteristics of muscle morphometry and meat tenderness of breasts and thighs of broilers raised in a free-range system.