Connective Tissue Proteins Research Articles

Lichen sclerosis of urethra (literature review using PUBMED sources http://www.ncbi.nlm.nih.gov/pubmed)

The review analyses data on possible causes of lichen sclerosis development, lists the histologic reports on changes in skin and urethra in genital lichen sclerosis with urethra strictures. The description of immunological barriers of urethra and the role of cell and humoral immunity disruption in development of pathological protein and extracellular matrix of connective tissue is provided. The review also lists the role of fibroblasts and fibroblast-mediated factors of inflammation in disruption of connective tissue and outlines the changes of extracellular matrix during immune response along with the influence of matrix metalloproteinases and their inhibitors. The data on regulating role of sex hormones, role of folate cycle disorders and related increase of homocysteine blood levels on the protein structure and extracellular marix of skin and urethra connective tissue is provided. A role of androgen deficiency in development of lichen sclerosis is listed. Finally the review describes the natural course of lichen sclerosis development and lists the methods of substitutive urethroplasties along with the materials used for urethra stricture treatment.

Carpal tunnel syndrome: The role of collagen gene variants

IntroductionThe direct causes of idiopathic carpal tunnel syndrome (CTS) are still unknown. It is suggested that pathology of the tendons and other connective tissue structures within the carpal tunnel may play a role in its aetiology. Variants in genes encoding connective tissue proteins, such as type V collagen, have previously been associated with CTS. Since variants within other collagen genes, such as type I, XI and XII collagen, have previously been associated with modulating the risk of musculoskeletal soft tissue injuries, the aim of this study was to determine whether variants within COL1A1, COL11A1, COL11A2 and COL12A1 were associated with CTS. MethodsSelf-reported Coloured South African participants, with a history of carpal tunnel release surgery (CTS, n=103) and matched control (CON, n=150) participants without any reported history of CTS symptoms were genotyped for COL1A1 rs1800012 (G/T), COL11A1 rs3753841 (T/C), COL11A1 rs1676486 (C/T), COL11A2 rs1799907 (T/A) and COL12A1 rs970547 (A/G). ResultsThe TT genotype of COL11A1 rs3753841 was significantly over-represented in the CTS group (21.4%) compared to CON group (7.9%, p=0.004). Furthermore, a trend for the T minor allele to be over-represented in the CTS group (p=0.055) with a significant association when only female participants (p=0.036) were investigated was observed. Constructed inferred pseudo-haplotypes including a previously investigated COL5A1 variant, rs71746744 (−/AGGG), suggest gene–gene interactions between COL5A1 and COL11A1 modulate the risk of CTS. DiscussionThese findings provide further information of the role of the genetic risk factors and the possible role of variations in collagen fibril composition in the aetiology of CTS. Genetic factors could potential be included in models developed to identify indivisuals at risk of CTS. Strategies that target modifiable risk factors to mitigate the effect of non-modifiable risk factors, such as the genetic risk, could be also developed to reduce incidence and morbidity of CTS.

Towards generation of bioactive peptides from meat industry waste proteins: Generation of peptides using commercial microbial proteases

Five commercially available food-grade microbial protease preparations were evaluated for their ability to hydrolyse meat myofibrillar and connective tissue protein extracts to produce bioactive peptides. A bacterial-derived protease (HT) extensively hydrolysed both meat protein extracts, producing peptide hydrolysates with significant in vitro antioxidant and ACE inhibitor activities. The hydrolysates retained bioactivity after simulated gastrointestinal hydrolysis challenge. Gel permeation chromatography sub-fractionation of the crude protein hydrolysates showed that the smaller peptide fractions exhibited the highest antioxidant and ACE inhibitor activities. OFFGEL electrophoresis of the small peptides of both hydrolysates showed that low isoelectric point peptides had antioxidant activity; however, no consistent relationship was observed between isoelectric point and ACE inhibition. Cell-based assays indicated that the hydrolysates present no significant cytotoxicity towards Vero cells. The results indicate that HT protease hydrolysis of meat myofibrillar and connective tissue protein extracts produces bioactive peptides that are non-cytotoxic, should be stable in the gastrointestinal tract and may contain novel bioactive peptide sequences.

Dosimetric impact of interplay effect in lung IMRT and VMAT treatment using in-house dynamic thorax phantom

The objective of this research was to determining of protein from connective tissue (protein) in the inner layer of organic and broiler chicken gizzard. The presence of collagens was observed by submersion with 0.1 M NaOH base pH 8 and without submersion. The physiochemical properties and characteristic of collagen from inner layer chicken gizzard such as FTIR spectra, element content, morphology and SDS-PAGE pattern were evaluated. FTIR spectrum in the sample without submersion shown collagen components had wave number that are in the range of wave number (3289-1078 cm-1) bovine collagen. While, FTIR spectrum in the sample with submersion exhibited removal of molecular functional groups and decreasing intensity of infrared absorption. The element content and morphology of two samples indicated that the elements found in the samples were recognized as the elements generally found in proteins and had little structure at SEM micrograph. SDS-PAGE pattern demonstrated that collagen from inner layer chicken gizzard had >120 kDa on molecular unit weight indicating that type 1 collagen is a major component of inner layer chicken gizzard collagen. This study demonstrated the existence of collagen from exploited bio-waste to be an alternative possible source for collagen production.

The influence of meat muscle structural properties on mechanical and texture parameters of canned ham

The aim of this study was to determine the relationships between mechanical-rheological properties as well as muscle texture parameters and their physico-chemical and structural characteristics in the course of different production phases of canned ham. Their mechanical-rheological, texture as well as physico-chemical and structural properties were analysed at each phase of the performed experiments. Injection and plasticisation in both kinds of ham muscles caused loosening of muscle fibres and partial extraction of muscle and connective tissue proteins. It should be emphasised that musculus quadriceps was characterised by a higher dynamics of changes in the fibre structure in comparison with the semimembranosus muscle. This found its expression in the analysed mechanical-rheological and texture as well as physico-chemical parameters. However, as a result of pasteurisation, values of all the analysed texture determinants, i.e. hardness, shearing force, cohesiveness and gumminess failed to exhibit statistically significant differences between one another in the case of both of the examined muscles.

Cell response on the biomimetic scaffold of silicon nano- and micro-topography.

Silicon scaffolds were synthesized in a low-pressure furnace via a vapor-liquid-solid (VLS) mechanism. Structural dimensions of silicon scaffolds were tunable in the synthesis to satisfy diverse requirements for cell culture applications. Cylindraceous SiNWs structurally resemble fibrous proteins in connective tissue and the extracellular matrix (ECM), which are main cell adhesion substrata in vivo. Hemispherical silicon microbroccolis (SiMBs) possess large contact area with microscale topology for cell contact and attachment. Mouse 3T3 fibroblasts were cultured on microscale and nanoscale silicon structures with different surface modifications. Silicon scaffolds were functionalized by several physical and chemical vapor deposition methods to modify scaffold surface physical and chemical properties. Metal-coated SiNWs and SiMBs had been demonstrated and compared for their ability to provide mechanical support sites for cell adhesion and promote cell proliferation and maintain normal cell functionality. Scanning electron microscopy (SEM) micrographs at high magnification show cell-scaffold interactions, and immunofluorescence images reveal nuclear DNAs and actin cytoskeleton distribution on nanostructure covered substrates and selected biomarker expression was analyzed by enzyme-linked immunosorbent assay (ELISA).

Multilayered dense collagen-silk fibroin hybrid: a platform for mesenchymal stem cell differentiation towards chondrogenic and osteogenic lineages.

Type I collagen is a major structural and functional protein in connective tissues. However, collagen gels exhibit unstable geometrical properties, arising from extensive cell-mediated contraction. In an effort to stabilize collagen-based hydrogels, plastic compression was used to hybridize dense collagen (DC) with electrospun silk fibroin (SF) mats, generating multilayered DC-SF-DC constructs. Seeded mesenchymal stem cell (MSC)-mediated DC-SF-DC contraction, as well as growth and differentiation under chondrogenic and osteogenic supplements, were compared to those seeded in DC and on SF alone. The incorporation of SF within DC prevented extensive cell-mediated collagen gel contraction. The effect of the multilayered hybrid on MSC remodelling capacity was also evident at the transcription level, where the expression of matrix metalloproteinases and their inhibitor (MMP1, MMP2, MMP3, MMP13 and Timp1) by MSCs within DC-SF-DC were comparable to those on SF and significantly downregulated in comparison to DC, except for Timp1. Chondrogenic supplements stimulated extracellular matrix production within the construct, stabilizing its multilayered structure and promoting MSC chondrogenic differentiation, as indicated by the upregulation of the genes Col2a1 and Agg and the production of collagen type II. In osteogenic medium there was an upregulation in ALP and OP along with the presence of an apatitic phase, indicating MSC osteoblastic differentiation and matrix mineralization. In sum, these results have implications on the modulation of three-dimensional collagen-based gel structural stability and on the stimulation and maintenance of the MSC committed phenotype inherent to the in vitro formation of chondral tissue and bone, as well as on potential multilayered complex tissues. Copyright © 2015 John Wiley & Sons, Ltd.

Preserved skeletal muscle protein anabolic response to acute exercise and protein intake in well-treated rheumatoid arthritis patients.

IntroductionRheumatoid arthritis (RA) is often associated with diminished muscle mass, reflecting an imbalance between protein synthesis and protein breakdown. To investigate the anabolic potential of both exercise and nutritional protein intake we investigated the muscle protein synthesis rate and anabolic signaling response in patients with RA compared to healthy controls.MethodsThirteen RA patients (age range 34–84 years; diagnosed for 1–32 years, median 8 years) were individually matched with 13 healthy controls for gender, age, BMI and activity level (CON). Plasma levels of C-reactive protein (CRP), interleukin (IL)-6 and tumor necrosis factor (TNF)-α were measured using enzyme-linked immunosorbent assay (ELISA) in resting blood samples obtained on two separate days. Skeletal muscle myofibrillar and connective tissue protein fractional synthesis rate (FSR) was measured by incorporation of the amino acid 13C6-phenylalanine tracer in the overnight fasted state for 3 hours (BASAL) and 3 hours after intake of whey protein (0.5 g/kg lean body mass) alone (PROT, 3 hrs) and in combination with knee-extensor exercise (EX) with one leg (8 × 10 reps at 70 % of 1RM; PROT + EX, 3 hrs). Expression of genes related to inflammatory signaling, myogenesis and muscle growth/atrophy were analyzed by real-time reverse transcriptase-polymerase chain reaction (RT-PCR).ResultsCRP was significantly higher in the RA patients (2.25 (0.50) mg/l) than in controls (1.07 (0.25) mg/l; p = 0.038) and so was TNF-α (RA 1.18 (0.30) pg/ml vs. CON 0.64 (0.07) pg/ml; p = 0.008). Muscle myofibrillar protein synthesis in both RA patients and CON increased in response to PROT and PROT + EX, and even more with PROT + EX (p < 0.001), with no difference between groups (p > 0.05). The gene expression response was largely similar in RA vs. CON, however, expression of the genes coding for TNF-α, myogenin and HGF1 were more responsive to exercise in RA patients than in CON.ConclusionsThe study demonstrates that muscle protein synthesis rate and muscle gene expression can be stimulated by protein intake alone and in combination with physical exercise in patients with well-treated RA to a similar extent as in healthy individuals. This indicates that moderately inflamed RA patients have maintained their muscle anabolic responsiveness to physical activity and protein intake.Electronic supplementary materialThe online version of this article (doi:10.1186/s13075-015-0758-3) contains supplementary material, which is available to authorized users.

Plasma Levels of Matrix Metalloproteinase (MMP)-2, MMP-9 and Tumor Necrosis Factor-α in Chronic Hepatitis C Virus Patients.

Background: In chronic HCV infection, pathological accumulation of the extracellular matrix is the main feature of liver fibrosis; that indicates the imbalanced rate of increased matrix synthesis to decreased breakdown of connective tissue proteins. Matrix metalloproteinases (MMPs) play a crucial role in remodeling of extracellular matrix. It is known that expression of MMPs is regulated by Tumor necrosis factor (TNF)-α. Also, levels of TNF-α in liver and serum are increased in chronic HCV patient. Accordingly, this study aimed to correlate the plasma levels of MMP-2, MMP-9 and TNF-α in chronic HCV patients with the pathogenesis of the liver. Methods: The current study was conducted on 15 fibrotic liver cases with detectable HCV RNA, 10 HCV cirrhotic liver cases, and 15 control subjects of matched age and sex. Plasma MMP-2, MMP-9 and TNF-α were measured by ELISA. Results: Data revealed that the MMP2, MMP9 and TNF-α levels showed a significant elevation in chronic HCV patients compared to control group (p= 0.001). But, no significant correlation was observed in levels of MMP-2, MMP-9, and TNF-α between fibrotic and cirrhotic cases. Conclusions: MMP-2, MMP-9 and TNF-α showed high reproducibility to differentiate chronic HCV patients from control group. On the contrary, MMP-2, MMP-9 and TNF-α were not able to differentiate fibrotic from cirrhotic liver cases. Thus, MMP-2, MMP-9 and TNF-α could not be correlated with the progression of liver disease. Rather they could be used as prognostic markers of liver fibrosis.

Features of connective tissue structure of ligaments of the uterus in female genital prolapse

Aim. To study the features of collagen I and III deposition and elastin in uterosacral ligaments and round ligaments of uterus in females with genital prolapse.&#x0D; Methods. The study was performed on surgical specimens and biopsies of uterosacral ligaments and round ligaments of uterus of 15 females with genital prolapse and 15 females without prolapse who also underwent metrectomy using abdominal access. Four tissue specimens were obtained from every patient, biopsy material was fixed in 10% neutral formalin and were embedded in paraffin, and cut for the paraffin slices of 4 μm. Specimens were stained by haematoxylin and eosine, Van Gieson’s picro-fuchsin stain and Weigert’s Resorcin-Fuchsin stain, immunohistochemistry (immunoperoxidase reactions) with primary antibodies to collagen I and III and elastin were also performed.&#x0D; Results. Morphologic study of the ligaments of the uterus in females with genital prolapse revealed fibrosis and fragmentation of elastin, diffuse atrophy, hyaline or mucinous degeneration of smooth muscle and extracellular matrix edema. Connective tissue disarrangement at genital prolapse was seen as decreased expression of collagen type I and elastin. Decreased elasticity determined over-stretching of uterosacral ligaments and round ligaments of uterus, which decreased microcirculation and promoted the ischemia of ligaments of uterus connective tissue. Disproportion of connective tissue proteins expression was enhanced by imbalance of collagen I and III, with the last, which is the least strong, prevailing. Stereotypic changes in the ligaments of uterus structures, seen as misallocation and placing of collagen and elastin fibers and, consequently, loosening of the elastic and collagen fibers, were revealed in patients with genital prolapse.&#x0D; Conclusion. Revealed features of collagen I and III and elastin deposition in uterosacral ligaments and round ligaments of uterus in females of reproductive age with genital prolapse allow predicting the risk for development and relapses of genital prolapse.

Static and cyclic mechanical loading of mesenchymal stem cells on elastomeric, electrospun polyurethane meshes.

Biomaterial substrates composed of semi-aligned electrospun fibers are attractive supports for the regeneration of connective tissues because the fibers are durable under cyclic tensile loads and can guide cell adhesion, orientation, and gene expression. Previous studies on supported electrospun substrates have shown that both fiber diameter and mechanical deformation can independently influence cell morphology and gene expression. However, no studies have examined the effect of mechanical deformation and fiber diameter on unsupported meshes. Semi-aligned large (1.75 μm) and small (0.60 μm) diameter fiber meshes were prepared from degradable elastomeric poly(esterurethane urea) (PEUUR) meshes and characterized by tensile testing and scanning electron microscopy (SEM). Next, unsupported meshes were aligned between custom grips (with the stretch axis oriented parallel to axis of fiber alignment), seeded with C3H10T1/2 cells, and subjected to a static load (50 mN, adjusted daily), a cyclic load (4% strain at 0.25 Hz for 30 min, followed by a static tensile loading of 50 mN, daily), or no load. After 3 days of mechanical stimulation, confocal imaging was used to characterize cell shape, while measurements of deoxyribonucleic acid (DNA) content and messenger ribonucleic acid (mRNA) expression were used to characterize cell retention on unsupported meshes and expression of the connective tissue phenotype. Mechanical testing confirmed that these materials deform elastically to at least 10%. Cells adhered to unsupported meshes under all conditions and aligned with the direction of fiber orientation. Application of static and cyclic loads increased cell alignment. Cell density and mRNA expression of connective tissue proteins were not statistically different between experimental groups. However, on large diameter fiber meshes, static loading slightly elevated tenomodulin expression relative to the no load group, and tenascin-C and tenomodulin expression relative to the cyclic load group. These results demonstrate the feasibility of maintaining cell adhesion and alignment on semi-aligned fibrous elastomeric substrates under different mechanical conditions. The study confirms that cell morphology is sensitive to the mechanical environment and suggests that expression of select connective tissue genes may be enhanced on large diameter fiber meshes under static tensile loads.

피부세포에서 옥돔 비늘로부터 추출한 펩타이드의 UVB에 대한 산화적 손상 및 광 노화 억제

생체에서 가장 많은 비율로 분포하고 있는 콜라겐 펩타이드는 동물의 뼈와 해양 생물의 비늘에 많이 함유되어 있다. 콜라겐은 동물 생체의 여러 결합조직에서 구조 단백질로 흔하게 발견된다. 또한, 이들은 생물 의료 자재, 제약, 화장품, 식품 및 가죽 산업에 널리 이용된다. 각종 어류 비늘에서 추출된 펩타이드는 UVB 조사에 의해 유도된 피부의 손상 및 광 노화에 대한 보호 효과가 있었다. 그럼에도 불구하고, UVB 조사에 대한 옥돔 비늘 유래의 펩타이드 특성은 명확히 알려져 있지 않다. 이 연구에서는 옥돔 비늘 추출물에서 분리된 1 kDa 이상(HMP)과 1 kDa 이하(LMP)의 펩타이드를 이용하여 UVB 조사에 의해 유도된 피부 손상과 광 노화에 대한 효과를 연구하였다. 이들 펩타이드는 농도 의존적으로 DPPH 라디칼 소거능을 보였으며 LMP는 HaCaT 인간 피부세포에서 UVB 조사에 의해 유도된 세포 지질 과산화 산물인 8-isoprostane 생성을 억제하였다. 그리고 LMP와 HMP는 B16F10 마우스 흑색종 세포에서 tyrosinase 활성 및 melanin 함량을 감소시켰으며 또한 HaCaT 세포에서 UVB로 유도된 elastase 활성을 감소시켰고 matrix metalloproteinase-1의 활성을 감소시켰다. 이러한 결과는 옥돔 비늘에서 유래된 펩타이드가 미백효과, 항산화제 및 광 노화 억제제로서 유용한 물질이 될 것으로 기대된다. Collagen peptides, which are found at high concentrations in the human body, are present in animal bones and the skin of marine organisms, namely, fish scales. Collagen is the most abundant structural protein of various connective tissues in animals. Furthermore, it is widely used in biomedical material, pharmaceutical, cosmetic, food, and leather industries. Peptides extracted from scales of various fish protect against ultraviolet B (UVB)-induced skin damage and photo-aging. However, the protective effects of collagen peptides derived from the scales of Branchiostegus japonicus against UVB exposure are unclear. This study investigated the effects of peptides larger than 1 kDa (high-molecular weight peptides [HMP]) and smaller than 1 kDa (low-molecular weight peptides [LMP]), derived from extracts of B. japonicus scales, against UVB-induced skin damage and photo-aging. These peptides scavenged 1,1-diphenyl-2-picrylhydrazyl radicals in a dose-dependent manner. In UVB-exposed HaCaT human keratinocytes, LMP inhibited 8-isoprostane generation, a marker of cellular lipid peroxidation. The peptides also suppressed the UVB-induced increase in tyrosinase activity and melanin content in B16F10 mouse melanoma cells. In addition, the LMP and HMP treatment suppressed UVB-induced elastase and matrix metalloproteinase-1 activities in the HaCaT cells. These results indicate that peptides derived from B. japonicus scales have antioxidant, antiphoto-aging, and skin-whitening effects.

Low elastin content of carotid plaques is associated with increased risk of ipsilateral stroke.

ObjectivesAtherosclerotic plaques with a low content of connective tissue proteins are believed to have an increased risk of rupture and to give rise to clinical events. The aim of the present study was to investigate if the content of elastin, collagen and of the matrix metalloproteinase (MMP) −1, −3, −9 and −12 in plaques removed at surgery can be associated with the occurrence of ipsilateral symptoms.MethodsThe atherosclerotic plaques of 221 patients undergoing carotid endarterectomy were analyzed and their composition was related to the incidence of preoperative, intraoperative and postoperative neurological events.ResultsElastin, collagen and MMP-12 contents were lower in males and diabetic patients. Elastin (P .010), MMP-3 (P .008) and MMP-9 (P < .0001) were lower, while MMP-1 (P .004) and MMP-9 (P .002) were higher in plaques of patients with preoperative symptoms, even after correction for the time between the occurrence of symptoms and surgery. Elastin and MMP-12 decreased (r = −0.17, P .009 and r = −.288, P <.0001 respectively) while MMP-1 (r = 0.17, P .012) and MMP-9 (r = .21 P <.0001) increased with age. After a mean follow-up time of 39.6 ± 16.6 months, 7.7% of patients had suffered one or multiple ipsilateral neurological events. Patients with plaque elastin levels lower than the median (52 mg/g) had increased post-operative incidence of ipsilateral stroke (P for trend 0.009 using Log Rank Chi-square test). This finding was confirmed when controlling for age, gender, hypertension, diabetes, smoking, pre-operative symptoms and statin usage in a Cox Proportional Hazard model (hazard ratio 7.38, 95% C.I. 1.50–36.31).ConclusionsThese observations support the concept that elastin may be important for plaque stability, and suggest that a low plaque content of elastin is associated with a higher risk for ipsilateral stroke.

A bienzyme electrochemical biosensor for the detection of collagen l-hydroxyproline

l-hydroxyproline (l-Hyp: trans-4-hydroxy-l-proline) is commonly found at high concentrations in connective tissue proteins such as collagen. It is a remarkably useful molecular marker because variation in the level of l-Hyp is associated with various diseases. Recently, the novel enzymes l-hydroxyproline epimerase and d-hydroxyproline dehydrogenase were isolated from bacteria. In this study, a novel electrochemical biosensor for l-Hyp was constructed using these two enzymes. l-hydroxyproline epimerase epimerized l-Hyp to d-hydroxyproline (d-Hyp: cis-4-hydroxy-d-proline), and d-Hyp was oxidized with the reaction catalyzed by d-hydroxyproline dehydrogenase and mediated by ferrocene. We found that the sensor could determine l-Hyp concentrations of 10–100μM with high-selectivity.

Gene expression of collagen metabolic proteins in the paraurethral connective tissue of women with urinary incontinence and small pelvic organ prolapse

Gene expression of collagen metabolic proteins in the paraurethral connective tissue of women with urinary incontinence and small pelvic organ prolapse

Cook Loss as a Function of Meat Heat Treatment and Regime

Heat treatment of meat causes different changes in the structure of meat, for example, decimation of cell films, tearing of muscle strands, tearing and disintegration of the connective tissue proteins, coagulation and gel development of the myofibrillar and sarcoplasmic proteins.The aim of the study presented in this paper was to investigate the effect of heat treatment by roasting and cooking at atmospheric pressure on cook loss of M. Longissimus dorsi of pork in the temperature range between 50°C and 100°C. Consequently were analyzed and the drip losses seen as a result of freezing and thawing of meat before heat treatment.The observed parameters amid tests indicated steady measurably critical change (P&lt;0.001) of observed qualities with temperature expanding amid the both hotness treatment forms in the given temperature range. The most ideal temperature in the core of the pork meat sample during heat treatment is in the temperature range somewhere around 70°C and 80°C. Heat treatment by cooking gave samples with less cook loss yield, compared to the heat treatment by roasting.

Role of the MAPKs/TGF-β1/TRAF6 Signaling Pathway in Atrial Fibrosis of Patients with Chronic Atrial Fibrillation and Rheumatic Mitral Valve Disease

Objective: Atrial remodeling is involved in atrial fibrillation (AF), and atrial fibrosis is an important marker of atrial remodeling. On the basis of our previous animal studies of the mitogen-activated protein kinases (MAPKs)/transforming growth factor β1 (TGF-β1)/tumor necrosis factor pathway in atrial fibrosis, we undertook investigation of this signaling pathway in atrial fibrosis of patients with chronic AF (CAF) and rheumatic mitral valve disease. Methods: Fifty-six rheumatic mitral valve disease patients were divided into CAF (course of AF >12 months) and sinus rhythm (SR) groups. Left atrial appendage tissue was collected during heart surgery, and pathological examination was done to evaluate atrial fibrosis. Protein and mRNA expression of TGF-β1, TRAF6 and connective tissue growth factor (CTGF) and protein expression of phosphorylated MAPKs and TGF-β-activated kinase 1 (TAK1) were measured. Results: Histological examination revealed that the severity of atrial fibrosis in CAF patients was significantly higher, mRNA and protein expression of TGF-β1, TRAF6 and CTGF in CAF were significantly increased, and the protein expression of phosphorylated MAPKs and TAK1 was significantly increased in CAF compared to SR patients. Conclusion: The MAPKs/TGF-β1/TRAF6 signaling pathway is involved in atrial fibrosis of CAF patients, and TRAF6 may become a new target for the treatment of atrial fibrosis.

Neuroimaging and psychophysiological investigation of the link between anxiety, enhanced affective reactivity and interoception in people with joint hypermobility.

Objective: Anxiety is associated with increased physiological reactivity and also increased “interoceptive” sensitivity to such changes in internal bodily arousal. Joint hypermobility, an expression of a common variation in the connective tissue protein collagen, is increasingly recognized as a risk factor to anxiety and related disorders. This study explored the link between anxiety, interoceptive sensitivity and hypermobility in a sub-clinical population using neuroimaging and psychophysiological evaluation.Methods: Thirty-six healthy volunteers undertook interoceptive sensitivity tests, a clinical examination for hypermobility and completed validated questionnaire measures of state anxiety and body awareness tendency. Nineteen participants also performed an emotional processing paradigm during functional neuroimaging.Results: We confirmed a significant relationship between state anxiety score and joint hypermobility. Interoceptive sensitivity mediated the relationship between state anxiety and hypermobility. Hypermobile, compared to non-hypermobile, participants displayed heightened neural reactivity to sad and angry scenes within brain regions implicated in anxious feeling states, notably insular cortex.Conclusions: Our findings highlight the dependence of anxiety state on bodily context, and increase our understanding of the mechanisms through which vulnerability to anxiety disorders arises in people bearing a common variant of collagen.

Characterisation of novel fungal and bacterial protease preparations and evaluation of their ability to hydrolyse meat myofibrillar and connective tissue proteins

The catalytic capability of four commercially available food-grade fungal and bacterial protease preparations (AFP, FPII, F60K and HT) was evaluated over a range of pH, temperature and substrate conditions using esterase and caseinolytic activity assays and time course hydrolysis over 120 and 60min of myofibrillar and connective tissue proteins, respectively. The protease preparations displayed similar casein hydrolysis kinetics and were active in hydrolysing BODIPY-FL casein to varying extents at postmortem aging meat pH (5.0–6.0). All of the four proteases exhibited selective hydrolytic activity towards meat myofibrillar proteins including myosin and actin. Significant hydrolysis of two meat tenderisation protein markers troponin T and desmin by the four proteases was detected by western blot. The results obtained indicate that the new fungal protease preparations AFP and FPII, bacterial protease preparation HT and the new source of fungal protease preparation F60K have potential for use in meat tenderising applications.

Impaired fibrous repair: a possible contributor to atherosclerotic plaque vulnerability in patients with type II diabetes.

Diabetes mellitus (DM) type II is increasing rapidly worldwide. Patients with DM II have a greater atherosclerotic burden and higher risk of developing cardiovascular complications. Inflammation has been proposed as the main cause for the high risk of atherosclerotic disease in DM II. In this study, we compared markers of inflammation and fibrous repair in plaques from subjects with and without DM II. Carotid endarterectomy specimens were obtained from 63 patients with and 131 without DM. Plaque structure, connective tissue proteins, inflammatory cells, and markers were analyzed by immunohistochemistry, ELISA, Mesoscale, and Luminex technology. Carotid plaques from diabetics had lower levels of extracellular matrix proteins, elastin, and collagen, which are critical for plaque stability. Plaques from diabetics had reduced levels of platelet-derived growth factor and matrix metalloproteinase-2, both important for tissue repair. No differences were observed in inflammatory markers in plaques from diabetic and nondiabetic patients. This study suggests that atherosclerotic plaques in subjects with DM II are more prone to rupture because of impaired repair responses rather than to increased vascular inflammation. Although this study did not have a mechanistic design, our findings suggest that targeting impaired repair responses in carotid plaques may help to increase our understanding of atherosclerotic plaque development and vulnerability in patients with DM II.