In vivo glycation-interplay between oxidant and carbonyl stress in bone.

Metabolic syndromes (eg, obesity, type 2 diabetes (T2D), atherosclerosis, and neurodegenerative diseases) and aging, they all have a strong component of carbonyl and reductive-oxidative (redox) stress. Reactive carbonyl (RCS) and oxidant (ROS) stress species are commonly generated as products or byproducts of cellular metabolism or are derived from the environment. RCS and ROS can play a dual role in living organisms. Some RCS and ROS function as signaling molecules, which control cellular defenses against biological and environmental assaults. However, due to their high reactivity, RCS and ROS inadvertently interact with different cellular and extracellular components, which can lead to the formation of undesired posttranslational modifications of bone matrix proteins. These are advanced glycation (AGEs) and glycoxidation (AGOEs) end products generated in vivo by non-enzymatic amino-carbonyl reactions. In this review, metabolic processes involved in generation of AGEs and AGOEs within and on protein surfaces including extracellular bone matrix are discussed from the perspective of cellular metabolism and biochemistry of certain metabolic syndromes. The impact of AGEs and AGOEs on some characteristics of mineral is also discussed. Different therapeutic approaches with the potential to prevent the formation of RCS, ROS, and the resulting formation of AGEs and AGOEs driven by these chemicals are also briefly reviewed. These are antioxidants, scavenging agents of reactive species, and newly emerging technologies for the development of synthetic detoxifying systems. Further research in the area of in vivo glycation and glycoxidation should lead to the development of diverse new strategies for halting the progression of metabolic complications before irreversible damage to body tissues materializes.

The importance of matrix in cardiomyogenesis: Defined substrates for maturation and chamber specificity.

Human embryonic stem cell-derived cardiomyocytes (hESC-CM) are a promising source of cardiac cells for disease modelling and regenerative medicine. However, current protocols invariably lead to mixed population of cardiac cell types and often generate cells that resemble embryonic phenotypes. Here we developed a combinatorial approach to assess the importance of extracellular matrix proteins (ECMP) in directing the differentiation of cardiomyocytes from human embryonic stem cells (hESC). We did this by focusing on combinations of ECMP commonly found in the developing heart with a broad goal of identifying combinations that promote maturation and influence chamber specific differentiation. We formulated 63 unique ECMP combinations fabricated from collagen 1, collagen 3, collagen 4, fibronectin, laminin, and vitronectin, presented alone and in combinations, leading to the identification of specific ECMP combinations that promote hESC proliferation, pluripotency, and germ layer specification. When hESC were subjected to a differentiation protocol on the ECMP combinations, it revealed precise protein combinations that enhance differentiation as determined by the expression of cardiac progenitor markers kinase insert domain receptor (KDR) and mesoderm posterior transcription factor 1 (MESP1). High expression of cardiac troponin (cTnT) and the relative expression of myosin light chain isoforms (MLC2a and MLC2v) led to the identification of three surfaces that promote a mature cardiomyocyte phenotype. Action potential morphology was used to assess chamber specificity, which led to the identification of matrices that promote chamber-specific cardiomyocytes. This study provides a matrix-based approach to improve control over cardiomyocyte phenotypes during differentiation, with the scope for translation to cardiac laboratory models and for the generation of functional chamber specific cardiomyocytes for regenerative therapies.

Matrix stiffness-related extracellular matrix signatures and the DYNLL1 protein promote hepatocellular carcinoma progression through the Wnt/ß-catenin pathway.

BACKGROUND: In hepatocellular carcinoma (HCC) treatment, first-line targeted therapy in combination with immune checkpoint inhibitors (ICIs) has improved patient prognosis, but the 5-year survival rate is far from satisfactory. Studies have shown that the extracellular matrix (ECM) is an essential part of the tumour microenvironment (TME) and participates in the progression of malignant tumours. ECM remodelling can enhance matrix stiffness in cirrhosis patients, induce an immunosuppressive microenvironment network, and affect the efficacy of targeted therapies and ICIs for treating HCC. However, the exact mechanism is still unclear. METHODS: We downloaded data from public databases, selected differentially expressed ECM proteins associated with matrix stiffness, constructed and validated a prognostic model of HCC using Lasso Cox regression, and investigated the roles and mechanism of one of the ECM proteins, dynein light chain LC8-type 1 (DYNLL1), in HCC proliferation, migration, and apoptosis via in vitro experiments. RESULTS: In this study, the risk score of the matrix stiffness-related ECM protein model effectively predicted the prognosis of HCC patients. The high- and low-risk subgroups of the model also showed differences in immune cells, immune functions, and drug sensitivity. DYNLL1 promoted HCC cell progression and migration and inhibited HCC cell apoptosis through the Wnt/ß-catenin pathway in vitro. CONCLUSION: The expression of matrix stiffness-related ECM proteins could be an independent predictor of HCC prognosis. DYNLL1, an oncogenic gene in HCC, has the potential to be a new target for HCC treatment.

Identification of extracellular matrix proteins in plasma as a potential biomarker for intervertebral disc degeneration.

PURPOSE: Recently, there has been significant focus on extracellular matrix proteolysis due to its importance in the pathological progression of intervertebral disc degeneration (IVDD). The present study investigates the circulating levels of extracellular matrix proteins in the plasma of IVDD and determines their potential relevance as biomarkers in disc degeneration. METHODS: Global proteomic analysis was performed in the plasma samples of 10 healthy volunteers (HV) and 10 diseased subjects (DS) after depletion of highly abundant proteins such as albumin and IgG. RESULTS: We identified 144 and 135 matrix-associated proteins in plasma samples from healthy volunteers (HV) and patients with disc degeneration (DS), respectively. Among these, 49 of the matrix-associated proteins were identical to the proteins found in intervertebral disc (IVD) tissues retrieved from the in-house library. Applying stringent parameters, we selected 28 proteins, with 26 present in DS and 21 in HV. 19 proteins were found common between the groups, two of which-aggrecan (ACAN) and fibulin 1 (FBLN1) - showed statistically significant differences. Specifically, ACAN was up-regulated and FBLN1 was down-regulated in the DS-plasma. In particular, DS-plasma exhibited specific expression of collagen type 2a1 (COL2A1), native to the nucleus pulposus. CONCLUSION: The distinct presence of collagen type 2a1 and the elevated expression of aggrecan in IVDD plasma may serve as the basis for the development of a potential biomarker for monitoring the progression of disc degeneration.

Perlecan: An Islet Basement Membrane Protein with Protective Anti-Inflammatory Characteristics.

Throughout the isolation process, human islets are subjected to destruction of the islet basement membrane (BM) and reduced oxygen supply. Reconstruction of the BM represents an option to improve islet function and survival post-transplant and may particularly be relevant for islet encapsulation devices and scaffolds. In the present study, we assessed whether Perlecan, used alone or combined with the BM proteins (BMPs) Collagen-IV and Laminin-521, has the ability to protect isolated human islets from hypoxia-induced damage. Islets isolated from the pancreas of seven different organ donors were cultured for 4-5 days at 2% oxygen in plain CMRL (sham-treated controls) or in CMRL supplemented with BMPs used either alone or in combination. Postculture, islets were characterized regarding survival, in vitro function and production of chemokines and reactive oxygen species (ROS). Individually added BMPs significantly doubled islet survival and increased in vitro function. Combining BMPs did not provide a synergistic effect. Among the tested BMPs, Perlecan demonstrated the significantly strongest inhibitory effect on chemokine and ROS production when compared with sham-treatment (p < 0.001). Perlecan may be useful to improve islet survival prior to and after transplantation. Its anti-inflammatory potency should be considered to optimise encapsulation and scaffolds to protect isolated human islets post-transplant.

Fabrication of ECM protein coated hollow collagen channels to study peripheral nerve regeneration.

Peripheral nerve injury is a prevalent clinical problem that often leads to lifelong disability and reduced quality of life. Although peripheral nerves can regenerate, recovery after severe injury is slow and incomplete. The current gold standard treatment, autologous nerve transplantation, has limitations including donor site morbidity and poor functional outcomes, highlighting the need for improved repair strategies. We developed a reproducible in vitro hollow channel collagen gel construct to investigate peripheral nerve regeneration (PNR) by exploring the influence of key extracellular matrix (ECM) proteins on axonal growth and regeneration. Channels were coated with ECM proteins: collagen IV, laminin, or fibronectin and seeded with dorsal root ganglia (DRG) collected from E16 rat embryos to compare the ability of the ECM proteins to enhance axonal growth. Robust axonal extension and Schwann cell (SC) infiltration were observed in fibronectin-coated channels, suggesting its superiority over other ECM proteins. Differential effects of ECM proteins on axons and SCs indicated direct growth stimulation beyond SC-mediated guidance. In vitro laceration injury modeling further confirmed fibronectin's superior pro-regenerative effects, showcasing its potential in enhancing axonal regrowth post-injury. Advancing in vitro modeling that closely replicates native microenvironments will accelerate progress in overcoming the limitations of current nerve repair approaches.

Fibrillar extracellular matrix produced by pericyte-like cells facilitates glioma cell dissemination.

Gliomagenesis induces profound changes in the composition of the extracellular matrix (ECM) of the brain. In this study, we identified a cellular population responsible for the increased deposition of collagen I and fibronectin in glioblastoma. Elevated levels of the fibrillar proteins collagen I and fibronectin were associated with the expression of fibroblast activation protein (FAP), which is predominantly found in pericyte-like cells in glioblastoma. FAP+ pericyte-like cells were present in regions rich in collagen I and fibronectin in biopsy material and produced substantially more collagen I and fibronectin in vitro compared to other cell types found in the GBM microenvironment. Using mass spectrometry, we demonstrated that 3D matrices produced by FAP+ pericyte-like cells are rich in collagen I and fibronectin and contain several basement membrane proteins. This expression pattern differed markedly from glioma cells. Finally, we have shown that ECM produced by FAP+ pericyte-like cells enhances the migration of glioma cells including glioma stem-like cells, promotes their adhesion, and activates focal adhesion kinase (FAK) signaling. Taken together, our findings establish FAP+ pericyte-like cells as crucial producers of a complex ECM rich in collagen I and fibronectin, facilitating the dissemination of glioma cells through FAK activation.

Integrin-Targeting Strategies for Adenovirus Gene Therapy.

Numerous human adenovirus (AdV) types are endowed with arginine-glycine-aspartic acid (RGD) sequences that enable them to recognize vitronectin-binding (αv) integrins. These RGD-binding cell receptors mediate AdV entry into host cells, a crucial early step in virus infection. Integrin interactions with adenoviruses not only initiate receptor-mediated endocytosis but also facilitate AdV capsid disassembly, a prerequisite for membrane penetration by AdV protein VI. This review discusses fundamental aspects of AdV-host interactions mediated by integrins. Recent efforts to re-engineer AdV vectors and non-viral nanoparticles to target αv integrins for bioimaging and the eradication of cancer cells will also be discussed.

Relationships between Osteopontin, Osteoprotegerin, and Other Extracellular Matrix Proteins in Calcifying Arteries.

Osteopontin (OPN) and osteoprotegerin (OPG) are glycoproteins that participate in the regulation of tissue biomineralization. The aim of the project is to verify the hypothesis that the content of OPN and OPG in the aorta walls increases with the development of atherosclerosis and that these proteins are quantitatively related to the main proteins in the extracellular arteries matrix. Quantitative and qualitative analyses of the OPN and OPG content in 101 aorta sections have been conducted. Additionally, an enzyme-linked immunosorbent assay (ELISA) test has been performed to determine the collagen types I-IV and elastin content in the tissues. Correlations between the biochemical data and patients' age/sex, atherosclerosis stages, and calcification occurrences in the tissue have been established. We are the first to report correlations between OPN or OPG and various types of collagen and elastin content (OPG/type I collagen correlation: r = 0.37, p = 0.004; OPG/type II collagen: r = 0.34, p = 0.007; OPG/type III collagen: r = 0.39, p = 0.002, OPG/type IV collagen: r = 0.27, p = 0.03; OPG/elastin: r = 0.42, p = 0.001; OPN/collagen type I: r = 0.34, p = 0.007; OPN/collagen type II: r = 0.52, p = 0.000; OPN/elastin: r = 0.61, p = 0.001). OPN overexpression accompanies calcium deposit (CA) formation with the protein localized in the calcium deposit, whereas OPG is located outside the CA. Although OPN and OPG seem to play a similar function (inhibiting calcification), these glycoproteins have different tissue localizations and independent expression regulation. The independent expression regulation presumably depends on the factors responsible for stimulating the synthesis of collagens and elastin.

Association of Tenascin-C Gene Polymorphisms with Risk of Acute Coronary Syndrome in South Indian Population: A Case-Control Genetic Association Study.

Background: The extracellular matrix (ECM) glycoprotein changes are associated with the pathogenesis and complications of atherosclerosis, leading to acute coronary syndrome (ACS). Tenascin-C (TNC), an ECM protein, has been implemented in the pathogenesis, diagnosis, and prognosis of patients with cardiovascular disease. Aim: The study aimed to compare the genetic variants of the TNC gene (rs13321, rs2104772, and rs12347433) between South Indians with ACS and healthy participants. Materials and Methods: This case-control study recruited 150 ACS patients as cases and 150 healthy participants as controls. TNC genotyping was performed using TaqMan 5'-exonuclease allele discrimination assay. Serum TNC levels were measured by enzyme-linked immunosorbent assay. Results: Serum TNC levels were significantly higher in cases compared with controls. No significant difference was observed in allele and genotype frequencies of rs13321, rs2104772, and rs12347433 between cases and controls, which was confirmed by dominant, recessive, codominant, and homozygotic genetic models. The patients with heterozygous genotypes of rs13321, rs2104772, and rs12347433 had significantly lower serum TNC levels than patients with respective homozygous genotypes. Haplotype analyses revealed that the C-T-A haplotype in the block of rs13321-rs12347433-rs2104772 was associated with lower ACS risk (OR = 0.33, 95% CI: 0.15 - 0.75; p = 0.005). Also, the C-T-T and G-T-A haplotypes of the TNC gene were associated with higher and lower serum TNC levels, respectively. Conclusion: Our study demonstrated no genetic association between single nucleotide polymorphisms of the TNC gene and ACS risk; however, the C-T-A haplotype of the TNC gene might be associated with reduced ACS risk in South Indians.

Aortic Cellular Heterogeneity in Health and Disease: Novel Insights Into Aortic Diseases From Single-Cell RNA Transcriptomic Data Sets.

Aortic diseases such as atherosclerosis, aortic aneurysms, and aortic stiffening are significant complications that can have significant impact on end-stage cardiovascular disease. With limited pharmacological therapeutic strategies that target the structural changes in the aorta, surgical intervention remains the only option for some patients with these diseases. Although there have been significant contributions to our understanding of the cellular architecture of the diseased aorta, particularly in the context of atherosclerosis, furthering our insight into the cellular drivers of disease is required. The major cell types of the aorta are well defined; however, the advent of single-cell RNA sequencing provides unrivaled insights into the cellular heterogeneity of each aortic cell type and the inferred biological processes associated with each cell in health and disease. This review discusses previous concepts that have now been enhanced with recent advances made by single-cell RNA sequencing with a focus on aortic cellular heterogeneity.

In Vivo and In Vitro Pro-Fibrotic Response of Lung-Resident Mesenchymal Stem Cells from Patients with Idiopathic Pulmonary Fibrosis.

Lung-resident mesenchymal stem cells (LR-MSC) are thought to participate in idiopathic pulmonary fibrosis (IPF) by differentiating into myofibroblasts. On the other hand, LR-MSC in IPF patients present senescence-related features. It is unclear how they respond to a profibrotic environment. Here, we investigated the profibrotic response of LR-MSC isolated from IPF and control (CON) patients. LR-MSC were inoculated in mice 48 h after bleomycin (BLM) instillation to analyze their contribution to lung damage. In vitro, LR-MSC were exposed to TGFß. Mice inoculated with IPF LR-MSC exhibited worse maintenance of their body weight. The instillation of either IPF or CON LR-MSC sustained BLM-induced histological lung damage, bronchoalveolar lavage fluid cell count, and the expression of the myofibroblast marker, extracellular matrix (ECM) proteins, and proinflammatory cytokines in the lungs. In vitro, IPF LR-MSC displayed higher basal protein levels of aSMA and fibronectin than CON LR-MSC. However, the TGFß response in the expression of TGFß, aSMA, and ECM genes was attenuated in IPF LR-MSC. In conclusion, IPF LR-MSC have acquired myofibroblastic features, but their capacity to further respond to profibrotic stimuli seems to be attenuated. In an advanced stage of the disease, LR-MSC may participate in disease progression owing to their limited ability to repair epithelial damage.

The viable bioengineered allogeneic cellularized construct StrataGraft® synthesizes, deposits, and organizes human extracellular matrix proteins into tissue type-specific structures and secretes soluble factors associated with wound healing.

BACKGROUND: StrataGraft® (allogeneic cultured keratinocytes and dermal fibroblasts in murine collagen-dsat) is an FDA-approved viable bioengineered allogeneic cellularized construct for adult patients with deep partial-thickness burns requiring surgery. We characterized the structural and functional properties of StrataGraft to improve product understanding by evaluating extracellular matrix (ECM) molecule distribution and secreted protein factor expression in vitro. METHODS: ECM protein expression was determined using indirect immunofluorescence on construct cross sections using commercial antibodies against collagen III, IV, VI, laminin-332, and decorin. Human collagen I expression was verified by enzyme-linked immunosorbent assay (ELISA) for collagen I C-terminal propeptide. Soluble protein factor secretion was quantified by multiplex biomarker assays and singleplex ELISA in conditioned media from meshed constructs. RESULTS: StrataGraft cellular components produced collagen I, collagen III, collagen VI, and decorin in patterns indicating an organized ECM. Distributions of collagen IV and laminin-332 indicated formation of basement membranes and dermal-epidermal junctions. Soluble protein factors were observed in the pg/cm2/h range from 1 h to the experiment end at 168 h. CONCLUSIONS: The organization of the ECM proteins was like human skin and the viable cellular components provided sustained secretion of soluble wound healing factors, making StrataGraft an attractive option for treating severe burns.

LSD1 Regulates Neurogenesis in Human Neural Stem Cells Through the Repression of Human-Enriched Extracellular Matrix and Cell Adhesion Genes.

Neurogenesis begins with neural stem cells undergoing symmetric proliferative divisions to expand and then switching to asymmetric differentiative divisions to generate neurons in the developing brain. Chromatin regulation plays a critical role in this switch. Histone lysine-specific demethylase LSD1 demethylates H3K4me1/2 and H3K9me1/2 but the mechanisms of its global regulatory functions in human neuronal development remain unclear. We performed genome-wide ChIP-seq of LSD1 occupancy, RNA-seq, and Histone ChIP-seq upon LSD1 inhibition to identify its repressive role in human neural stem cells. Novel downstream effectors of LSD1 were identified, including the Notch signaling pathway genes and human-neural progenitor-enriched extracellular matrix (ECM) pathway/cell adhesion genes, which were upregulated upon LSD1 inhibition. LSD1 inhibition led to decreased neurogenesis, and overexpression of downstream effectors mimicked this effect. Histone ChIP-seq analysis revealed that active and enhancer markers H3K4me2, H3K4me1, and H3K9me1 were upregulated upon LSD1 inhibition, while the repressive H3K9me2 mark remained mostly unchanged. Our work identifies the human-neural progenitor-enriched ECM pathway/cell adhesion genes and Notch signaling pathway genes as novel downstream effectors of LSD1, regulating neuronal differentiation in human neural stem cells.

Mechanistic role of Syzygium cumini (L.) Skeels in glycation induced diabetic nephropathy via RAGE-NF-κB pathway and extracellular proteins modifications: A molecular approach.

ETHNOPHARMACOLOGY RELEVANCE: Syzygium cumini (L.) Skeels (SC), an ancient medicinal plant, is used as a complementary and alternative medicine for treating diabetes mellitus and its associated complications, such as diabetic nephropathy (DN). Phytochemicals present in SC homeopathic formulations possess anti-glycemic, anti-glycation, anti-inflammatory, and antioxidant properties. Additionally, the non-enzymatic formation of advanced glycation end products (AGEs) increases during hyperglycemia in diabetes. AGEs interaction with their receptor of AGEs (RAGE) promotes inflammation via Nuclear Factor-κB (NF-κB) and the accumulation of Extracellular Matrix (ECM) proteins, contributing to the renal dysfunction in DN. However, the molecular mechanism through which SC formulations interact with the AGEs-RAGE-NF-κB pathway has not yet been investigated. AIM: This study aims to examine the impact of SC formulations on the RAGE-NF-κB pathway and ECM protein modifications in glycation-induced DN using a molecular approach. MATERIALS AND METHODS: Human serum albumin (10 mg/ml) was glycated with MGO (55 mM) in the presence of SC formulations - Mother tincture (MT), 30C, 200C for 7 days. Glycated samples were added to renal cells (HEK 293) for 24 h. Subsequently, cellular gene and protein expressions of RAGE, NF-κB, vascular endothelial growth factor (VEGF), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), collagen IV (Col IV), and fibronectin were determined using RT-qPCR and Western blot analysis. The immunofluorescence, luciferase assay, and chromatin immunoprecipitation techniques were employed to gain insights into glycation-induced NF-κB nuclear translocation, transcriptional activity, and its effect on RAGE promoter activity in SC-treated cells. RESULTS: SC formulations significantly downregulated glycation-induced elevated levels of RAGE and NF-κB. Mechanistically, SC formulations prevented NF-κB nuclear translocation, transcriptional activity, and RAGE promoter activity. Also, SC formulations significantly attenuated glycation-enhanced expressions of inflammatory cytokines (IL-6, TNF-α, and VEGF) and ECM proteins (Col IV and fibronectin). CONCLUSION: Our findings enlighten the molecular mechanism of SC in DN by targeting the AGEs-RAGE-NF-κB signaling pathway, inflammatory responses, and ECM accumulation. Hence, the study validates the protective role of SC formulations and signifies its novel potential for treating DN.

ENAM gene polymorphisms associated with dental anomalies in individuals with cleft lip and palate

Aim: This study aimed to investigate the occurrence of enamelin gene (ENAM) single nucleotide polymorphisms (SNP) and ENAM polymorphism association with dental anomalies (DA) in individuals with unilateral or bilateral cleft lip and palate (CLP). Methods: Saliva samples were collected from 147 individuals aged between 6 and 15 years-old, both genders, and divided into 4 groups: Group 1 (G1) - CLP and DA; Group 2 (G2) - CLP without DA; Group 3 (G3) - without CLP with DA; Group 4 (G4) - without CLP and DA. The genomic DNA was extracted from saliva samples and the following ENAM SNPs markers were genotyped: rs3796703, rs3796704, rs3796705, rs7671281, rs2609428, and rs35951442. Fisher exact and Pearson's Chi-square tests statistically analyzed the results (α=5%). Results: Individuals without CLP with DA (Group 3 - 19.2%) showed statistically higher prevalence of SNP rs2609428 heterozygotes (p=0.006) than individuals with CLP and DA (Group 1 - 0%). Individuals without CLP (10%) exhibited statistically higher prevalence of mutated heterozygotes/homozygous (p=0.028) than in individuals with CLP (1.3%). Conclusion: SNP rs2609428 marker of ENAM gene may be associated with dental anomalies in individuals without cleft lip and palate

General joint hypermobility in temporomandibular joint disease; clinical characteristics, biomarkers, and surgical aspects.

Objectives: This study aimed at identifying biomarkers in the temporomandibular joint (TMJ) synovial tissue analysing 28 extra cellular matrix proteins in TMJ diseased patients, classified with either general joint hypermobility (GJH) or normal joint mobility (NJM), and to compile clinical and protein characterisation to reveal potential surgical predictive factors. Study design: A prospective observational cohort study including 97 consecutive patients scheduled for TMJ surgery was performed. Joint mobility and several other predefined clinical variables were recorded. Synovial tissue was harvested during surgery followed by examination using multi-analytic profiling. A multivariate quantile regression model was used for analysis purposes. Results: The GJH/NJM ratio was 2:5. The GJH cohort were younger (P = 0.001) and more likely to be women (P = 0.026) compared to the NJM cohort. None of the protein concentrations could be correlated to joint mobility in the multivariate regression model, but often to the variable TMJ diagnosis. The surgical outcome after the six-month follow-up were equal between GJH and NJM patients. Conclusions: GJH was more common in the study cohort compared to general population frequencies, but GJH was not a negative factor for surgical outcome. Young age and female gender correlated to GJH. No TMJ biomarkers were GJH specific, and the results suggested that TMJ diagnosis more strongly correlated to the protein profile compared to GJH and the other investigated variables.

Focusing on the Native Matrix Proteins in Calcific Aortic Valve Stenosis.

Calcific aortic valve stenosis (CAVS) is a widespread valvular heart disease affecting people in aging societies, primarily characterized by fibrosis, inflammation, and progressive calcification, leading to valve orifice stenosis. Understanding the factors associated with CAVS onset and progression is crucial to develop effective future pharmaceutical therapies. In CAVS, native extracellular matrix proteins modifications, play a significant role in calcification in vitro and in vivo. This work aimed to review the evidence on the alterations of structural native extracellular matrix proteins involved in calcification development during CAVS and highlight its link to deregulated biomechanical function.

Postnatal development of extracellular matrix and vascular function in small arteries of the rat.

Introduction: Vascular extracellular matrix (ECM) is dominated by elastic fibers (elastin with fibrillin-rich microfibrils) and collagens. Current understanding of ECM protein development largely comes from studies of conduit vessels (e.g., aorta) while resistance vessel data are sparse. With an emphasis on elastin, we examined whether changes in postnatal expression of arteriolar wall ECM would correlate with development of local vasoregulatory mechanisms such as the myogenic response and endothelium-dependent dilation. Methods: Rat cerebral and mesenteric arteries were isolated at ages 3, 7, 11, 14, 19 days, 2 months, and 2 years. Using qPCR mRNA expression patterns were examined for elastin, collagen types I, II, III, IV, fibrillin-1, and -2, lysyl oxidase (LOX), and transglutaminase 2. Results: Elastin, LOX and fibrillar collagens I and III mRNA peaked at day 11-14 in both vasculatures before declining at later time-points. 3D confocal imaging for elastin showed continuous remodeling in the adventitia and the internal elastic lamina for both cerebral and mesenteric vessels. Myogenic responsiveness in cannulated cerebral arteries was detectable at day 3 with constriction shifted to higher intraluminal pressures by day 19. Myogenic responsiveness of mesenteric vessels appeared fully developed by day 3. Functional studies were performed to investigate developmental changes in endothelial-dependent dilation. Endothelial-dependent dilation to acetylcholine was less at day 3 compared to day 19 and at day 3 lacked an endothelial-derived hyperpolarizing factor component that was evident at day 19. Conclusion: Collectively, in the rat small artery structural remodeling and aspects of functional control continue to develop in the immediate postnatal period.

Anti-Fibrotic Effects of RF Electric Currents.

Hypertrophic scars and keloids are two different manifestations of excessive dermal fibrosis and are caused by an alteration in the normal wound-healing process. Treatment with radiofrequency (RF)-based therapies has proven to be useful in reducing hypertrophic scars. In this study, the effect of one of these radiofrequency therapies, Capacitive Resistive Electrical Transfer Therapy (CRET) on biomarkers of skin fibrosis was investigated. For this, in cultures of human myofibroblasts treated with CRET therapy or sham-treated, proliferation (XTT Assay), apoptosis (TUNEL Assay), and cell migration (Wound Closure Assay) were analyzed. Furthermore, in these cultures the expression and/or localization of extracellular matrix proteins such as α-SMA, Col I, Col III (immunofluorescence), metalloproteinases MMP1 and MMP9, MAP kinase ERK1/2, and the transcription factor NFκB were also investigated (immunoblot). The results have revealed that CRET decreases the expression of extracellular matrix proteins, modifies the expression of the metalloproteinase MMP9, and reduces the activation of NFκB with respect to controls, suggesting that this therapy could be useful for the treatment of fibrotic pathologies.