Production Of Extracellular Matrix Components Research Articles

Markers of Dermal Fibroblast Subpopulations for Viable Cell Isolation via Cell Sorting: A Comprehensive Review.

Fibroblasts are among the most abundant cell types in the human body, playing crucial roles in numerous physiological processes, including the structural maintenance of the dermis, production of extracellular matrix components, and mediation of inflammatory responses. Despite their importance, fibroblasts remain one of the least characterized cell populations. The advent of single-cell analysis techniques, particularly single-cell RNA sequencing (scRNA-seq) and fluorescence-activated cell sorting (FACS), has enabled detailed investigations into fibroblast biology. In this study, we present an extensive analysis of fibroblast surface markers suitable for cell sorting and subsequent functional studies. We reviewed over three thousand research articles describing fibroblast populations and their markers, characterizing and comparing subtypes based on their surface markers, as well as their intra- and extracellular proteins. Our detailed analysis identified a variety of distinct fibroblast subpopulations, each with unique markers, characteristics dependent on their location, and the physiological or pathophysiological environment. These findings underscore the diversity of fibroblasts as a cellular population and could lead to the development of novel diagnostic and therapeutic tools.

The role of IL-1, IL-6 and TNF-α in breast cancer development and progression

Background: Breast cancer (BC) is the most diagnosed cancer among women worldwide and the second-most cause of women's deaths. The interleukin-1 (IL-1), interleukin-6 (IL-6), and tumour necrosis factor-α (TNF-α) are critical for BC pathogenesis. They participate in BC development and progression by regulating several pathways. The findings of this review paper can potentially guide the development of targeted therapies that can improve the prognosis and treatment outcomes for BC patients. Objective: To make a comprehensive and up-to-date review of the original papers on the role of IL-1, IL-6, and TNF-α in BC development and progression. Method: This literature review is an iterative and objective analysis of the English original papers published in the last five years, which linked IL-1, IL-6, TNF-α, and BC. Result: IL-1, IL-6, and TNF-α significantly affect angiogenesis, proliferation, apoptosis, survival, and metastatic in BC by regulating the PI3K-PKB/Akt, JNK, IL-6/JAK/STAT3, Ras/Raf, AKT, MAPK, and NF-κB pathways. They also modulate the TME by promoting the production of extracellular matrix components and stimulating the recruitment of immune cells. Conclusion: Inhibiting IL-1, IL-6, and TNF-α and their downstream signalling intermediates could be promising strategies for suppressing BC development and progression. Further in-depth research is necessary to develop novel targeted therapies and improve patient outcomes.

Identification of β-cycloidal-derived mono-carbonyl curcumin analogs as potential interleukin-6 inhibitor to treat wound healing through QSAR, molecular docking, MD simulation, MM-GBSA calculation

Interleukin-6 (IL-6) is a cytokine that involved in the different phases of wound healing. It is responsible for promoting inflammation, regulating tissue repair scar formation, stimulating the production of extracellular matrix components and recruiting immune cells to the wound site. Therefore, suppressing IL-6 is beneficial for wound healing. However, no small molecules are currently available in the market against the IL-6. As a result, this research gap motivates us to find a potential inhibitor. This study aimed to investigate the wound healing potential of novel β-cycloidal-derived mono-carbonyl curcumin analogs reported in the literature through screening a series of computational studies. The calculated pIC50 value of 18 compounds (below 10) showed that all compounds may have potential therapeutic efficacy. Molecular docking studies revealed that compound C12 (−45.6044 kcal/mol) bound most strongly in the active site of IL-6 compared to the FDA-approved drug clindamycin (−42.3223). The Molecular Dynamic (MD) simulation displayed that lead compound C12 had the highest stability in the active site of IL-6 compared to the reference drug clindamycin. Furthermore, MMGBSA results indicated that C12 (−20.28 kcal/mol) had the highest binding energy compared to clindamycin (−8.36 kcal/mol). The ADMET analysis predicted that C12 are favourable for drug candidates. This study recommended compound C12 as a lead IL-6 inhibitor for future testing and development as therapeutics for wound healing. Communicated by Ramaswamy H. Sarma

Multifunctional Wound Curation Dressing Material FemuFrost─An Antioxidant-Loaded Nanoemulsion Frosted Patch of Poly(vinyl alcohol) and Hyaluronic Acid.

The wound curation dressing material should own explicit elements to aggrandize wound cessation. The cryogel of poly(vinyl alcohol) (PVA) and hyaluronic acid (HA) is deemed to promote the angiogenesis, production of extracellular matrix components, granulation, and epithelialization. The research aims to tailor and evaluate the composite PVA/HA cryogel ingrained ferulic acid-loaded nanoemulsion patch labeled as PH-FemuFrost to improve the therapeutic properties and mechanical strength of the patches. The PH-FemuFrost exhibited a water uptake capacity of 268 ± 15.07%, porosity of 70.52 ± 7.4%, and 48.62 ± 2.2% in vitro degradation. The texture analysis revealed the improved mechanical properties of PH-FemuFrost in terms of burst strength and stiffness. The PH-FemuFrost exhibited in vitro antioxidant and antimicrobial activity against Staphylococcus aureus and Candida albicans species. The wound healing efficiency of PH-FemuFrost patches was significantly increased than blank PVA-HA patches. The groups treated with PH-FemuFrost exhibited a dense network of collagen type 1 in comparison to negative and PVA-HA groups. The normal skin and healed skin exhibited parallel arrangement of type I collagen fibers toward the skin. The levels of inflammatory mediators such as IL-6 (p value < 0.0001), IL-22 (p value 0.0098), and TNF-α levels (p value < 0.0001) of PH-FemuFrost is significantly reduced compared to the negative group.

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According to scientific sources, in 30 % of patients with postCOVID-19 syndrome, additional examination reveals respiratory symptoms, namely a significant decrease in the diffusion capacity of the lungs (DLCO) and associated damage to the pulmonary interstitium. A comparison of interstital lung disease caused by SARS-CoV-2 virus and idiopathic pulmonary fibrosis pathogenesis revealed several common mechanisms: excessive activation of the immune system, secretion of proinflammatory and profibrotic cytokines, damage to the epithelium and endothelium, excessive production of extracellular matrix components, and a decrease in the functional properties of the lungs. Interstitial lung diseases (ILD) is a heterogeneous group characterized by various clinical, radiological, and pathological features that largely affect the lung parenchyma. Pulmonary fibrosis is a characteristic feature of various types of ILD, which are characterized by the presence of chronic inflammation and/or collagen deposition in the interalveolar space, which leads to insufficient passage of oxygen and carbon dioxide molecules through the alveolar epithelium. The presented clinical cases demonstrate the diversity of the pulmonary interstitium lesions in long-COVID, which can be systematized by the correspondingly classified interstitial lung disease. Treatment of these diseases according to the accepted recommendations had a positive effect. Key words: post-COVID-19 syndrome, long-COVID-19, pulmonary fibrosis, interstitial lung diseases, idiopathic pulmonary fibrosis, hypersensitivity pneumonitis.

Asteroid impact: the potential of astrocytes to modulate human neural networks within organoids.

Astrocytes are a vital cellular component of the central nervous system that impact neuronal function in both healthy and pathological states. This includes intercellular signals to neurons and non-neuronal cells during development, maturation, and aging that can modulate neural network formation, plasticity, and maintenance. Recently, human pluripotent stem cell-derived neural aggregate cultures, known as neurospheres or organoids, have emerged as improved experimental platforms for basic and pre-clinical neuroscience compared to traditional approaches. Here, we summarize the potential capability of using organoids to further understand the mechanistic role of astrocytes upon neural networks, including the production of extracellular matrix components and reactive signaling cues. Additionally, we discuss the application of organoid models to investigate the astrocyte-dependent aspects of neuropathological diseases and to test astrocyte-inspired technologies. We examine the shortcomings of organoid-based experimental platforms and plausible improvements made possible by cutting-edge neuroengineering technologies. These advancements are expected to enable the development of improved diagnostic strategies and high-throughput translational applications regarding neuroregeneration.

Catechin hydrate ameliorates cerulein‑induced chronic pancreatitis via the inactivation of TGF‑β/Smad2 signaling.

Chronic pancreatitis (CP) is a pancreatic inflammatory disease associated with histological changes, including fibrosis, acinar cell loss and immune cell infiltration, and leads to damage of the pancreas, which results in pain, weight loss and loss of pancreas function. Catechin or catechin hydrate (CH) has antioxidant, anticancer and immune‑regulatory effects. However, unlike other catechins, the antifibrotic effects of (+)‑CH have not been widely studied in many diseases, including CP. Therefore, the anti‑fibrotic effects of (+)‑CH against CP were evaluated in the present study. To assess the prophylactic effects of CH, (+)‑CH (1, 5 or 10mg/kg) or ethanol was administered 1h before first cerulein (50µg/kg) injection. To assess the therapeutic effects, (+)‑CH (5mg/kg) or ethanol was administered after cerulein injection for one or two weeks. In both methods, cerulein was injected intraperitoneally into mice once every hour, six times a day, four times a week, for a total of three weeks, to induce CP. The data showed that (+)‑CH markedly inhibited glandular destruction and inflammation during CP. Moreover, (+)‑CH prevented pancreatic stellate cell (PSC) activation and the production of extracellular matrix components, such as fibronectin 1 and collagens, which suggested that it may act as a novel therapeutic agent. Furthermore, the mechanism and effectiveness of (+)‑CH on pancreatic fibrosis were investigated in isolated PSCs. (+)‑CH suppressed the activation of Smad2 and fibrosis factors that act through transforming growth factor‑β (TGF‑β) or platelet‑derived growth factor. These findings suggest that (+)‑CH exhibits antifibrotic effects in cerulein‑induced CP by inactivating TGF‑β/Smad2 signaling.

Carbon dioxide-induced decrease in extracellular pH enhances the production of extracellular matrix components by upregulating TGF-β1 expression via CREB activation in human dermal fibroblasts.

Mild acidification caused by transcutaneous administration of carbon dioxide (CO2 ) has been reported to improve some epidermal skin impairments, such as desquamation and inflammation; however, its effects on dermal tissue remain unclear. Here, we examined the effect and mechanism of mild acidity on extracellular matrix (ECM) protein production in normal human dermal fibroblasts (NHDFs). To achieve this, the skin permeability of CO2 and its effect on intradermal pH were evaluated by treating reconstructed human skin equivalents (HSEs) with a CO2 -containing formulation. Additionally, NHDFs were cultured in a pH-adjusted medium (pH 6.5). CO2 successfully permeated HSEs and reduced the intradermal pH. Decreased extracellular pH activated CREB, upregulated TGF-β1 expression, promoted the production of elastic and collagen fibres, and increased hyaluronan concentration in NHDFs. Additionally, the low pH-induced increase in TGF-β1 expression was attenuated via the RNAi-mediated suppression of the expression of CREB1 and proton-sensing G protein-coupled receptors (GPCRs), including GPR4 and GPR65. Moreover, low pH-induced CREB activation was suppressed by the inhibition of the cAMP/PKA and PLC/PKC signalling pathways. Taken together, a CO2 -induced decrease in intradermal pH may promote ECM production in NHDFs via the upregulation of TGF-β1 expression, which was mediated by the activation of the GPCR signalling pathway and CREB, indicating that CO2 could be used to treat ultraviolet radiation-induced photoaging, intrinsic ageing and ECM deterioration.

Уровень мРНК гена Nos2 как маркер фиброгенеза печени крыс, индуцированного тиоацетамидом

The aim of this paper was to evaluate the potential of the mRNA level of the Nos2 gene as a marker of fibrogenesis in rats at different stages of thioacetamide-induced liver fibrosis and cirrhosis. Materials and methods. The experiment involved 117 mature male Wistar rats weighing 190–210 g. Liver fibrosis and cirrhosis were induced by a thioacetamide solution administered through a gastric catheter at a dose of 200 mg per 1 kg of body weight 2 times a week. The dynamics of the process was studied at 9 timepoints over the course of 17 weeks. Nos2 mRNA level in the liver was detected by means of real-time polymerase chain reaction. The stage of fibrosis was determined in histological sections stained using the Mallory method according to the Ishak semi-quantitative scale. Results. Throughout the experiment, Nos2 mRNA had practically no reaction to the thioacetamide-induced liver fibrogenesis. At the mild fibrosis stage (F1), an insignificant rise in the level of Nos2 mRNA was noted (within 5 %). Intensive development of fibrosis (F2–F4/F5) and an increase in the production of extracellular matrix components were accompanied by an increase in the level of Nos2 mRNA with a peak value exceeding the initial level (control group value) by the factor of 1.69 (р &lt; 0.05). At the point of transition of fibrosis to cirrhosis (F5), a decrease in the level of mRNA of the target gene was observed, and at the stage of definite cirrhosis (F6), a subsequent drop below the initial level was detected. Thus, according to the data obtained, Nos2 mRNA has the greatest potential as a marker of liver fibrogenesis at the stage of advanced fibrosis, but cannot act as a marker at the early stages. Moreover, Nos2 mRNA level cannot be used as a marker when assessing the degree of cirrhosis and its development dynamics.

Adaption of Pseudomonas ogarae F113 to the Rhizosphere Environment-The AmrZ-FleQ Hub.

Motility and biofilm formation are two crucial traits in the process of rhizosphere colonization by pseudomonads. The regulation of both traits requires a complex signaling network that is coordinated by the AmrZ-FleQ hub. In this review, we describe the role of this hub in the adaption to the rhizosphere. The study of the direct regulon of AmrZ and the phenotypic analyses of an amrZ mutant in Pseudomonas ogarae F113 has shown that this protein plays a crucial role in the regulation of several cellular functions, including motility, biofilm formation, iron homeostasis, and bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) turnover, controlling the synthesis of extracellular matrix components. On the other hand, FleQ is the master regulator of flagellar synthesis in P. ogarae F113 and other pseudomonads, but its implication in the regulation of multiple traits related with environmental adaption has been shown. Genomic scale studies (ChIP-Seq and RNA-Seq) have shown that in P. ogarae F113, AmrZ and FleQ are general transcription factors that regulate multiple traits. It has also been shown that there is a common regulon shared by the two transcription factors. Moreover, these studies have shown that AmrZ and FleQ form a regulatory hub that inversely regulate traits such as motility, extracellular matrix component production, and iron homeostasis. The messenger molecule c-di-GMP plays an essential role in this hub since its production is regulated by AmrZ and it is sensed by FleQ and required for its regulatory role. This regulatory hub is functional both in culture and in the rhizosphere, indicating that the AmrZ-FleQ hub is a main player of P. ogarae F113 adaption to the rhizosphere environment.

Liver sinusoidal endothelial S1pr2 regulates experimental liver fibrosis through YAP/TGF-β signaling pathway.

The hepatic vascular niche plays an important role in the pathological process of liver fibrosis. Liver sinusoidal endothelial cells (LSECs) predominantly compose hepatic vascular niches. Endothelial cell (EC)-expressing sphingosine 1-phosphate receptor 2 (S1pr2) plays an essential role in the regulation of vascular functions. Nevertheless, it remains unknown whether liver LSEC-S1pr2 might modulate pathological liver fibrosis. In this study, liver fibrosis was induced by hepatotoxin carbon tetrachloride (CCl4 ). The expression of S1pr2 is significantly downregulated in liver sinusoidal endothelial cells after CCl4 treatment. The loss of S1pr2 in LSECs significantly alleviated liver fibrosis after chronic insult, whereas the overexpression of S1pr2 in LSECs accentuated liver fibrogenesis. In vivo experiments further revealed that the deficiency of S1pr2 in LSECs dampened hepatic stellate cell (HSC) activation, while overexpression of S1pr2 in LSECs enhanced HSC activation with more extracellular matrix component production. Mechanistically, LSEC-S1pr2 activates the YAP signaling pathway to potentiate the transactivation of TGF-β, which acts on HSCs in a paracrine manner, and thus aggravated liver fibrosis. Taken together, our results uncover a novel pathological mechanism of liver fibrosis in which LSEC-S1pr2 plays an important role in modulating the development of liver fibrosis, providing a future novel therapy target against liver fibrogenesis.

Blood Inflammatory-like and Lung Resident-like Eosinophils Affect Migration of Airway Smooth Muscle Cells and Their ECM-Related Proliferation in Asthma

Airway remodeling is a hallmark feature of asthma, and one of its key structural changes is increased airway smooth muscle (ASM) mass and disturbed extracellular matrix (ECM) homeostasis. Eosinophil functions in asthma are broadly defined; however, we lack knowledge about eosinophil subtypes' interaction with lung structural cells and their effect on the airway's local microenvironment. Therefore, we investigated the effect of blood inflammatory-like eosinophils (iEOS-like) and lung resident-like eosinophils (rEOS-like) on ASM cells via impact on their migration and ECM-related proliferation in asthma. A total of 17 non-severe steroid-free allergic asthma (AA), 15 severe eosinophilic asthma (SEA) patients, and 12 healthy control subjects (HS) were involved in this study. Peripheral blood eosinophils were enriched using Ficoll gradient centrifugation and magnetic separation, subtyped by using magnetic separation against CD62L. ASM cell proliferation was assessed by AlamarBlue assay, migration by wound healing assay, and gene expression by qRT-PCR analysis. We found that blood iEOS-like and rEOS-like cells from AA and SEA patients' upregulated genes expression of contractile apparatus proteins, COL1A1, FN, TGF-β1 in ASM cells (p < 0.05), and SEA eosinophil subtypes demonstrated the highest effect on sm-MHC, SM22, and COL1A1 gene expression. Moreover, AA and SEA patients' blood eosinophil subtypes promoted migration of ASM cells and their ECM-related proliferation, compared with HS (p < 0.05) with the higher effect of rEOS-like cells. In conclusion, blood eosinophil subtypes may contribute to airway remodeling by upregulating contractile apparatus and ECM component production in ASM cells, further promoting their migration and ECM-related proliferation, with a stronger effect of rEOS-like cells and in SEA.

Application of carbon-coated nanomultilayer sintered porous titanium microprosthesis for the repair of osteochondral defects of the knee joint

We constructed a carbon-coated nanomultilayer (CNM) sintered porous titanium (Ti) microprosthesis for the optimal treatment of osteochondral defects of the knee joint. Physicochemical property tests revealed that the porosity of the constructed porous Ti-CNM prosthesis was ∼75%, while the pore size ranged 300–400 μm. The prosthesis had an elastic modulus (9.18 GPa) and compressive strength (98.3 MPa) similar to bone tissue. Furthermore, the CNM effectively reduced the roughness of the prosthesis surface. In animal experiments, the porous Ti-CNM improved the mineralization ability of osteoblasts in bone defects, as indicated by antialkaline phosphatase and osteocalcin, and improved bone mineral density, trabecular thickness, average trabecular number, and cortical bone thickness in the defective regions, thereby shortening the repair time. In addition, porous Ti-CNM effectively improved the production of extracellular matrix components in cartilage defects, such as collagen I, collagen II, and aggrecan, thereby enhancing the repair of cartilage defects and effectively preventing the degeneration of the opposite joint. The porous Ti-CNM prosthesis thus demonstrates great therapeutic potential for middle-aged patients with osteoarthritis.

Application and evaluation of the effectiveness of tissue stimulators in the prevention of skin aging

Skin’s natural capability to regenerate and rebuild itself is widely used in aesthetic cosmetology. The activity of dermal fibroblasts is reduced with age, which leads to the degradation of collagen and elastin. Additionally, the proliferation ability diminishes, consequently affecting and weakening cell regeneration processes. Tissue stimulation leads to multiplication of fibroblasts, protein synthesis and production of extracellular matrix components. The study aimed to analyze the effect of tissue stimulators depending on the type of active substance used to improve the skin density, its hydration, depth of wrinkles, color and face oval. The additional goal was to evaluate respondents’ knowledge about the function and use of the tissue stimulators in the prevention of skin aging.

When healing turns into killing - the pathophysiology of pancreatic and hepatic fibrosis.

Disorders such as pancreatic or hepatic fibrosis are a cruel reminder that disruption of the delicate physiological balance could result in severe pathological consequences. Fibrosis is usually associated with chronic diseases and manifests itself as excessive deposition of the extracellular matrix, which gradually leads to the replacement of the cellular components by fibrotic lesions, significantly compromising normal tissue functions. The main cellular mediators of fibrosis are different populations of tissue fibroblasts, predominantly hepatic and pancreatic stellate cells in the liver and pancreas, respectively. These cells undergo a phenotypic switch in response to (bio)chemical or physical stimuli and acquire a myofibroblast-like phenotype characterised by increased contractile and adhesive properties, elevated expression of certain cytoskeletal and membrane proteins, and prominent production of extracellular matrix components. In the past few decades, a substantial scientific effort has been undertaken to investigate the pathogenesis of fibrosis. Here, cellular mechanisms of hepatic and pancreatic fibrosis, their aetiological factors, associated diseases and prospective therapies are discussed. New therapies against fibrosis are likely to be focused on regulation of hepatic/pancreatic stellate cell physiology as well as normalisation of the organ mechanostasis.

Triple Cross-Linked Hyaluronic Acid Based on Tri-Hyal Technique Has More Durable Effect on Dermal Renewal.

BackgroundHyaluronic acid (HA)-based fillers are applied to treat facial wrinkles and volume loss. Many efforts have been made to improve properties of HA to prolong the duration in aesthetic indications. A new cross-linking technique called “Tri-Hyal”, could make HAs to achieve desired rheological characteristics. HAs synthesized by Tri-Hyal are triple cross-linked and sustained-release, which could increase duration of promoting skin rejuvenation after injection.PurposeTo evaluate the efficiency and persistence of HAs with Tri-Hyal on skin rejuvenation and further investigate underlying mechanisms, we compared the performances of cross-linked HA (AF) based on Tri-Hyal with another highly acceptable HA filler (Res) in vivo and in vitro.MethodsMale BALB/c mice were divided into three groups, treated with AF, Res and vehicle, respectively. Skin biopsies were taken on day 0, 30, 90 and 180 after injection and hematoxylin and eosin (H&E), Masson’s trichrome (MT), immunohistochemical (IHC) stainings for CD31, TGF-β and MMP9 were performed. EdU incorporation, cell counting kit-8 (CCK-8), SA-β-Gal staining and activity were measured by biochemical analysis. RFP-GFP-LC3 adeno virus was used for autophagic flux detection. Protein levels of CD44, P62 and LC3I/II were detected by Western blot. Reactive oxygen species (ROS) level was detected by flow cytometry with DCFH-DA probe.ResultsThe AF synthesized by Tri-Hyal showed persistent dermal structural correction without attenuation up to 6 months, which was illustrated by skin thickness, formation of elastic fibers and vascular density. Consistently, in fibroblasts the AF improved cell proliferation and slowed the senescent in vitro. Furthermore, it promoted cellular autophagy to reduce ROS level, which would account for its function in skin renewal.ConclusionThe HA with Tri-Hyal could stimulate the production of extracellular matrix components more persistently than traditional HA fillers. In terms of mechanisms, it delayed senescence in dermal fibroblasts through reducing oxidative stress mediated by induction of autophagy.

Regulation of cell cycle and differentiation markers by pathogenic, non-pathogenic and opportunistic skin bacteria

Skin is the first line of defense against the physical, chemical and the biological environment. It is an ideal organ for studying molecular responses to biological infections through a variety of skin cells that specialize in immune responses. Comparative analysis of skin response to pathogenic, non-pathogenic, and commensal bacteria would help in the identification of disease specific pathways for drug targets. In this study, we investigated human breast reduction skin responses to Cutibacterium acnes (C. acnes), Staphylococcus aureus (S. aureus), Staphylococcus epidermidis (S. epidermidis), and TLR1/2 agonist using Affymetrix microarray chips. The Pam3CSK4 solution and bacterial cultures were prepared and inoculated in steel rings, that were placed on the acetone treated epidermis in a petri dish. After 24 h incubation, 8 mm punch biopsies were taken from the center of the ring, and RNA was extracted. The genome-wide expression was then analyzed using Affymetrix HG-133A gene chip microarray. We found that the C. acnes and S. aureus boosted the production of extracellular matrix components and attenuated the expression of differentiation markers. The above responses were mediated through the TLR2 pathway. Skin also responded to S. aureus and C. acnes by inducing the genes of the cell cycle machinery; this response was not TLR2-dependent. S. aureus induced, whereas C. acnes suppressed the genes associated with apoptosis; this was also not TLR2-dependent. Moreover, S. epidermis apparently did not lead to changes in gene expression. We conclude that the breast reduction skin is a very useful model to study the global gene expression in response to bacterial treatments.

Morphofunctional Properties of Corneal Stromal Cells.

Human corneal stromal cells were isolated by enzymatic digestion from a new source, lenticules obtained during laser vision correction by the ReLEx SMILe method. The resulting culture was mainly presented by fibroblast-like cells with a phenotype CD90-/CD73+/CD105+/keratocan-/lumican-/ALDH1A1+ that differentiate into keratocytes in a specialized medium. The concentration of fetal calf serum-derived growth factors affects the rate of proliferation, production of erythropoietin and brain neurotrophic factor by corneal fibroblasts, and to a lesser extent, their migration activity and production of extracellular matrix components. Thus, the high functional potential of fibroblast-like cells isolated from stromal lenticles can be used to develop cell technologies in ophthalmology.

Effects and mechanism of age on the stiffness and the fibrotic phenotype of fibroblasts of human hypertrophic scar

Objective: To explore the effects and potential molecular mechanism of age on the stiffness and the fibrotic phenotype of fibroblasts (Fbs) of human hypertrophic scar. Methods: The experimental research method was used. From January to June 2020, the surgically removed hypertrophic scar tissue of 10 scar patients (4 males and 6 females) and residual full-thickness normal skin tissue of 10 cases (5 males and 5 females, aged 7-41 years) were collected after operation in Department of Burns and Plastic Surgery of the Fourth Medical Center of the PLA General Hospital. The hypertrophic scar tissue of 6 patients aged (10.7±1.6) years was included into the young group and the hypertrophic scar tissue of 4 patients aged (40.0±2.2) years was included into the elderly group according to the age of patients. For the normal skin tissue and scar tissue in the two groups, hematoxylin eosin (HE) staining was performed to observe the tissue morphology, Masson staining was performed to observe the morphology and arrangement of collagen and quantify the content of collagen, and scanning electron microscope was used to observe the microscopic difference of dermal collagen fibers after the samples were freeze-dried and metal coated. The stiffness of scar tissue in the two groups was measured by atomic force microscope under the liquid phase. The scar tissue in the two groups was collected and the Fbs were isolated and cultured. The morphological differences of the Fbs were observed under the inverted phase contrast microscope, and the protein expression of paxillin was detected with cellular immunofluorescence to reflect the morphology of the Fbs. Cellular immunofluorescence was used to detect the expressions of pro-fibrosis protein α-smooth actin (α-SMA), transforming growth factor-β1 (TGF-β1), and type Ⅰ collagen, mechanotransduction-related protein Yes-associated protein (YAP), and the proliferation-related protein Ki67. Real-time fluorescent quantitative reverse transcription polymerase chain reaction was used to detect the mRNA expressions of pro-fibrosis genes of TGF-β1, α-SMA, and type Ⅰ collagen, fibrosis inhibiting gene of TGF-β3, and mechanotransduction-related genes of Rho-associated protein 1 (ROCK1) and YAP. Data were statistically analyzed with one-way analysis of variance and least significant difference t test. Results: HE staining showed that the epidermal layer of normal skin was uneven, and blood vessels and sweat glands could be seen in the dermal layer; the epidermal layer of the scar tissue in the two groups was relatively flat, and blood vessels and sweat glands were rare. Masson staining and scanning electron microscopy showed that the collagen fibers in normal skin arranged loosely and disorderly, while the collagen fibers in scar tissue of the two groups arranged densely and orderly, and the collagen fibers in scar tissue of the young group were denser than those of the elderly group. The collagen content in scar tissue of the young group and the elderly group was significantly higher than that of the normal skin tissue (t=8.02, 3.15, P<0.05 or P<0.01), and the collagen content in scar tissue of the elderly group was significantly lower than that of the young group (t=4.84, P<0.05). The dermal stiffness of scar tissue in the elderly group was (50.3±1.1) kPa, significantly higher than (35.2±0.8) kPa in the young group (t=11.43, P<0.05). There were no obvious differences in the morphology of scar Fbs in the two groups observed under inverted phase contrast microscope and by cellular immunofluorescence. The expressions of type Ⅰ collagen and TGF-β1 in scar Fbs cytoplasm of the elderly group were significantly higher than those in the young group, while the expressions of α-SMA in scar Fbs cytoplasm were close in the two groups. The expressions of YAP in cytoplasm and nucleus of scar Fbs in the elderly group were significantly higher than those in the young group, while the expressions of Ki67 in scar Fbs nucleus of the two groups were close. The mRNA expressions of TGF-β1 and type Ⅰ collagen in scar Fbs of the elderly group were significantly higher than those in the young group (t=2.87, 4.85, P<0.05 or P<0.01), the mRNA expression of TGF-β3 in scar Fbs of the elderly group was significantly lower than that in the young group (t=3.36, P<0.05), and the mRNA expressions of α-SMA in scar Fbs of the two groups were close (t=1.14, P>0.05). The mRNA expressions of ROCK1 and YAP in scar Fbs of the elderly group were significantly higher than those in the young group (t=2.98, 7.60, P<0.05 or P<0.01). Conclusions: The elderly are prone to scar healing after skin injury. The molecular mechanism may be attributed to the production of extracellular matrix components with higher stiffness, which increases tissue stiffness and thereby activates the expressions of ROCK and YAP/transcriptional co-activator with PDZ-binding motif genes, promoting pro-fibrosis gene and protein expression.

Hyaluronan Hydrogels for Injection in Superficial Dermal Layers: An In Vitro Characterization to Compare Performance and Unravel the Scientific Basis of Their Indication.

Background: Skinboosters represent the latest category of hyaluronan (HA) hydrogels released for aesthetic purposes. Different from originally developed gels, they are intended for more superficial injections, claiming a skin rejuvenation effect through hydration and possibly prompting biochemical effects in place of the conventional volumetric action. Here, three commercial skinboosters were characterized to unravel the scientific basis for such indication and to compare their performances. Methods: Gels were evaluated for water-soluble/insoluble-HA composition, rheology, hydration, cohesivity, stability and effect, in vitro, on human dermal fibroblasts towards the production of extracellular matrix components. Results: Marked differences in the insoluble-hydrogel amount and in the hydrodynamic parameters for water-soluble-HA chains were evidenced among the gels. Hydration, rigidity and cohesivity also varied over a wide range. Sensitivity to hyaluronidases and Reactive Oxygen Species was demonstrated allowing a stability ranking. Slight differences were found in gels’ ability to prompt elastin expression and in ColIV/ColI ratio. Conclusions. A wide panel of biophysical and biochemical parameters for skinboosters was provided, supporting clinicians in the conscious tuning of their use. Data revealed great variability in gels’ behavior notwithstanding the same clinical indication and unexpected similarities to the volumetric formulations. Data may be useful to improve customization of gel design toward specific uses.