Production Of Collagen Fibers Research Articles

Didecyldimethylammonium chloride-induced lung fibrosis may be associated with phospholipidosis.

In the current study, we dosed Didecyldimethylammonium chloride (DDAC) in mice by pharyngeal aspiration for 28 days or 90 days (weekly) and tried to elucidate the relationship between lamellar body formation and the lesions. When exposed for 28 days (0, 5, 10, 50, and 100 μg/head), all the mice in the 50 and 100 μg/head groups died since Day 2 after the third dosing (Day 16 after the first dosing). Edema, necrosis of bronchiolar and alveolar epithelium, and fibrinous exudate were observed in the lungs of all the dead mice, and chronic inflammatory lesions were observed in the lung tissues of alive mice. When dosed with DDAC of 0, 1, 4, and 8 μg/head for 13 weeks, the total number of pulmonary cells and the pulmonary levels of pro- and anti-inflammatory cytokines significantly increased, and chronic inflammatory lesions were detected with the production of collagen, collagen fibers, and lamellar body-like structures. Swelling of the nuclear envelope and nucleoplasmic components and generation of lipid droplets were also notably observed in the lung tissues of DDAC (8 μg/head)-treated mice. Furthermore, transcriptomic analysis performed using human bronchial epithelial cells showed that DDAC affected the expression of DNA damage, ER stress, lipid metabolism, and transcription regulation-related genes at 6 h after treatment, as it did 24 h treatment and that early growth response factor 1 gene was added to a list of the most up-regulated genes. Meanwhile, cytokines that are associated with the pathology of chronic lung diseases (IL-11, IL-24, and TGF-β) were slightly increased in the lung of DDAC-treated mice, and only the pulmonary level of CCL-2, but not CXCL-1 and CCL-3, increased in both sexes of mice. More importantly, the GM-CSF level increased dose-dependently in the lungs of both sexes of mice exposed to DDAC. Considering that the wound-healing process can take several weeks to complete, we suggest that DDAC-induced pulmonary fibrosis may be attributable to disruption of the wound-healing process due to continuous exposure to DDAC. We also hypothesize that the formation of lamellar bodies may be attributable to lysosomal accumulation of phospholipids separated from the destroyed lung tissue membrane.

Microfocused Ultrasound in Regenerative Aesthetics: A Narrative Review on Mechanisms of Action and Clinical Outcomes.

Microfocused ultrasound with visualization (MFU-V) is widely used in aesthetic medicine for skin tightening and rejuvenation. However, its role in regenerative aesthetics and its precise mechanism of action are not fully understood. This narrative review aims to contextualize and articulate the mechanism of action of MFU-V, evaluate its role in regenerative aesthetics, and assess its effectiveness based on existing clinical, histological, and skin-mechanical studies. A comprehensive literature search was performed to collect and analyze studies on MFU's biological mechanisms, clinical outcomes, and impact on extracellular matrix (ECM) regeneration. The review integrates findings from clinical trials, histological analyses, and biomechanical assessments to provide a cohesive understanding of MFU-V's role in aesthetic medicine. MFU-V emits focused ultrasound energy that penetrates multiple skin layers and the superficial musculoaponeurotic system, creating localized thermal coagulation points. These points initiate biological responses that recruit fibroblasts and stimulate the production of new collagen and elastin fibers. Enhanced ECM protein synthesis leads to significant improvements in skin biomechanics and quality, reducing skin laxity and enhancing appearance. Clinical studies support these findings, showing improvements in skin firmness and texture following MFU-V treatment. Through analyzing the underlying biological mechanisms and the observable clinical outcomes, this narrative review sets the stage for a comprehensive understanding of the mechanism of action and role of MFU-V in regenerative aesthetics.

Histopathological Correlation Between High Endothelial Venule Neogenesis and the Tumor Microenvironment in Lung Adenocarcinoma.

The dynamic interplay between cancer cells and the microenvironment involves a wide range of intricate relationships that evolve during different stages of tumor progression. Recent attention has focused on high endothelial venules (HEVs), specialized endothelial cells in tumors with a unique cuboidal shape similar to those in lymph nodes. Previous animal studies have shown that normalization of tumor angiogenesis through anti-VEGFR2 therapy promotes HEV formation. However, few reports exist regarding the relationship between HEVs and preexisting blood vessels or interstitial fibers. In this study, we histologically examined whether tumor vascular structure correlates with HEV neogenesis. A total of 109 patients with pathological stage I lung adenocarcinoma who had undergone curative lung resection at our Institute between 2012 and 2016 were included. HEVs were identified by anti-peripheral node addressin (PNAd) staining. Immunostaining and Elastica-Masson-Goldner staining were performed on tumor sections and quantified. PNAd-positive cells were identified in 102 (93.6%) patients. Nearly all PNAd-positive cells were located within or near immune cell clusters. We investigated the correlation between microvessel structures or interstitial fibers and the number/density of PNAd-positive vessels, but no significant correlation was found. Since PNAd-positive cells were concentrated in immune cell aggregates, we focused our analysis specifically on these regions. Immune cell aggregates with abundant PNAd-positive vessels had a greater microvessel density along with by rich collagen fiber production, and displayed a more mature morphological phenotype of HEVs. The generation of PNAd-positive cells in tumors is governed by an angiogenetic mechanism distinct from that of broader tumor microenvironment. Furthermore, the accumulation of immune cells is associated with increased HEV maturation.

Pingchuan formula improve airway remodeling via regulation of the nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3/interleukin-1β and C-Jun N-terminal kinase pathways.

Asthma is a prevalent chronic inflammatory airway disease that affects both adults and children. Inflammation-induced airway remodeling can lead to irreversible damage to the airways. Traditional Chinese medicine (TCM) plays a significant role in healthcare, offering potential improvements for chronic airway inflammation associated with asthma. The objective of this study is to investigate the efficacy of Pingchuan formula (PCF) in treating asthma and explore its underlying mechanisms. The asthmatic model mice were sensitized on days 1 and 7, followed by aerosolized OVA challenge for a total of 21 times starting from day 14, spanning weeks 3 to 9. PCF was administered daily after the first challenge. The mice were orally dosed daily based on their individual body weights for a continuous period of 47 days. The examined items encompassed proteomic analysis of the target proteins impacted by PCF. The levels of interleukins IL-1β, IL-18, and transforming growth factor-β (TGF-β) in bronchoalveolar lavage fluid (BALF) were measured using ELISA. Immunohistochemistry was employed to assess the expression levels of nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3), caspase-1, and TGF-β in the airways. Western blotting and real-time quantitative PCR analysis were conducted to determine NLRP3 and caspase-1 expression levels. Additionally, Western blotting was performed to evaluate C-Jun N-terminal kinase (JNK), phosphorylated JNK (p-JNK), matrix metalloproteinase-9 (MMP-9), N-cadherin, E-cadherin, and tenascin C (T-NC) expression. Compared to the asthma model group, histological analysis using hematoxylin and eosin (HE) staining and Masson staining revealed that PCF exhibited a significant reduction in airway inflammation exudation and collagen fiber production in asthmatic mice. The proteomics analysis revealed that there were 174 proteins exhibiting differential expression in the PCF group compared to the asthma model group, indicating a strong association with negative regulation of the cell cycle and inflammation in the airways of asthmatic individuals. The PCF also exhibited a significant reduction in the protein and mRNA expressions of NLRP3 and caspase-1 in lung tissue (P<0.05). Additionally, it decreased the protein expressions of ASC, p-JNK, MMP-9, E-cadherin, and T-NC while increasing N-cadherin levels (P<0.05). The inflammatory factors IL-1β, IL-18 and TGF-β were reduced (P<0.05). This study revealed that Pingchuan Decoction can inhibit airway remodeling by inhibiting NLRP/IL-1β and JNK pathway activation, and effectively improve airway histological inflammation and remodeling in mice.

A Review on Dermal Wound Repair and Regeneration Using Antimicrobial-Loaded Microspheres Incorporated into Bovine Collagen Scaffold

In this paper, the developed microsphere-incorporated collagen scaffold presents a promising solution for delivering drugs over wound surfaces in a uniform and sustained manner. The biomaterials utilized in this system are of natural origin, minimizing potential toxicity from core materials, and collagen and gelatin exhibit active wound-healing properties. The collagen scaffold used for the delivery device offers several advantages, including minimizing dressing frequency, facilitating easier examination, and providing added aesthetic value. Furthermore, the protein-based biomaterial scaffold acts as a template for the extracellular matrix in the skin, enhancing the maturation of wounds and enabling the transition to the accelerated production of mature and aligned collagen fibers. The controlled release of antimicrobial drugs through denatured collagens and gelatin microspheres, as well as the efficient healing observed in in vivo studies, demonstrate the potential of this system for effective wound care. Overall, the incorporation of ciprofloxacin-loaded microspheres in porous collagen scaffold offers sustained releases of ciprofloxacin in infected environments, as supported by histological examination showing well-formed epidermis and dermis in the connective tissue of the skin. The system’s ability to heal full-thickness wounds within a significantly shorter time frame compared to antibiotic-incorporated collagen sponges further emphasizes its efficacy in wound healing.

Collagen Synthesis During Wound Repair in Infected Albino Rats Using Ciprofloxacin-Loaded Gelatin Microspheres Incorporated into a Collagen Scaffold: A Histological Approach Using Masson’s Trichrome Staining

The production of collagen fibers is essential for wound healing because it creates a scaffold of collagen on which new cells may move and proliferate. It indicates cellular activity and improves strength and flexibility. Collagen synthesis is influenced by a number of factors, including age, health, infection, and diet. Collagen dressings often have the ability to increase the production of collagen. Collagen production can be adversely affected by infected cutaneous wounds, which can result in a delayed healing process, a higher risk of scarring, weakened tissue, and functional impairment. For this reason, in order to speed up wound healing, antimicrobial agents have been added to the collagen scaffold. Furthermore, the prolonged delivery of antimicrobial agent-loaded gelatin microspheres to infected wounds promotes quicker wound healing and effective collagen synthesis in the granulated tissue. These scaffolds may make superior wound dressings in clinical settings in light of this relationship.

Exercise improves cardiac fibrosis by stimulating the release of endothelial progenitor cell-derived exosomes and upregulating miR-126 expression.

Cardiac fibrosis is an important pathological manifestation of various cardiac diseases such as hypertension, coronary heart disease, and cardiomyopathy, and it is also a key link in heart failure. Previous studies have confirmed that exercise can enhance cardiac function and improve cardiac fibrosis, but the molecular target is still unclear. In this review, we introduce the important role of miR-126 in cardiac protection, and find that it can regulate TGF-β/Smad3 signaling pathway, inhibit cardiac fibroblasts transdifferentiation, and reduce the production of collagen fibers. Recent studies have shown that exosomes secreted by cells can play a specific role through intercellular communication through the microRNAs carried by exosomes. Cardiac endothelial progenitor cell-derived exosomes (EPC-Exos) carry miR-126, and exercise training can not only enhance the release of exosomes, but also up-regulate the expression of miR-126. Therefore, through derivation and analysis, it is believed that exercise can inhibit TGF-β/Smad3 signaling pathway by up-regulating the expression of miR-126 in EPC-Exos, thereby weakening the transdifferentiation of cardiac fibroblasts into myofibroblasts. This review summarizes the specific pathways of exercise to improve cardiac fibrosis by regulating exosomes, which provides new ideas for exercise to promote cardiovascular health.

Radiofrequency Treatment Attenuates Age-Related Changes in Dermal-Epidermal Junctions of Animal Skin.

The dermal-epidermal junction (DEJ) is essential for maintaining skin structural integrity and regulating cell survival and proliferation. Thus, DEJ rejuvenation is key for skin revitalization, particularly in age-related DEJ deterioration. Radiofrequency (RF) treatment, known for its ability to enhance collagen fiber production through thermal mechanisms and increase heat shock protein (HSP) expression, has emerged as a promising method for skin rejuvenation. Additionally, RF activates Piezo1, an ion channel implicated in macrophage polarization toward an M2 phenotype and enhanced TGF-β production. This study investigated the impact of RF treatment on HSP47 and HSP90 expression, known stimulators of DEJ protein expression. Furthermore, using in vitro and aged animal skin models, we assessed whether RF-induced Piezo1 activation and the subsequent M2 polarization could counter age-related DEJ changes. The RF treatment of H2O2-induced senescent keratinocytes upregulated the expression of HSP47, HSP90, TGF-β, and DEJ proteins, including collagen XVII. Similarly, the RF treatment of senescent macrophages increased Piezo1 and CD206 (M2 marker) expression. Conditioned media from RF-treated senescent macrophages enhanced the expression of TGF-β and DEJ proteins, such as nidogen and collagen IV, in senescent fibroblasts. In aged animal skin, RF treatment increased the expression of HSP47, HSP90, Piezo1, markers associated with M2 polarization, IL-10, and TGF-β. Additionally, RF treatment enhanced DEJ protein expression. Moreover, RF reduced lamina densa replication, disrupted lesions, promoted hemidesmosome formation, and increased epidermal thickness. Overall, RF treatment effectively enhanced DEJ protein expression and mitigated age-related DEJ structural changes by increasing HSP levels and activating Piezo1.

Expression analysis of leptin in nephrogenesis and renal carcinogenesis

The complex phenomenon of renal development involves several signaling molecules. Any alteration in the developmental process could largely influence the organogenesis, thus predisposing to several adulthood diseases. Leptin is a pleiotropic gene secreted by adipose cells. However, the purview of its actions is much beyond merely the extent of human adipose reserve. It regulates several cellular mechanisms such as cell proliferation, inflammation, vasculogenesis, and the production of collagen fibres. Further leptins are thought to play a putative role in embryogenesis and tumorigenesis. The aim of thIS study was to investigate the localization of the protein in fetal and cancer kidney in an attempt to understand the role of the protein in fetal kidney development and in renal cancer. Leptin expression was evaluated by subjecting tissue sections from paraffin-embedded blocks of renal tissues (fetal, adult and cancer) to immunohistochemistry staining. The tissues were scored based on the staining pattern and percentage of immunoreactive cells. The tissues were subjected to haematoxylin and eosin stain before performing immunohistochemistry. The images were analyzed and photographed. Mild staining for leptin was observed in the tubules of fetal and adult kidneys. Mild to moderate staining was seen in membranes of renal cell carcinoma tissues. It appears such that leptin may not be a key factor or rather a temporary factor in the developmental process of the kidney. The low levels of leptin in normal adult renal tissues may be physiologically significant. The role of leptin in the renal cell carcinoma progression is sceptible.

Modified Zhenwu Tang delays chronic renal failure progression by modulating oxidative stress and hypoxic responses in renal proximal tubular epithelial cells

BackgroundTubulointerstitial fibrosis (TIF) is a critical pathological feature of chronic renal failure (CRF), with oxidative stress (OS) and hypoxic responses in renal proximal tubular epithelial cells playing pivotal roles in disease progression. This study explores the effects of Modified Zhenwu Tang (MZWT) on these processes, aiming to uncover its potential mechanisms in slowing CRF progression. MethodsWe used adenine (Ade) to induce CRF in rats, which were then treated with benazepril hydrochloride (Lotensin) and MZWT for 8 weeks. Assessments included liver and renal function, electrolytes, blood lipids, renal tissue pathology, OS levels, the hypoxia-inducible factor (HIF) pathway, inflammatory markers, and other relevant indicators. In vitro, human renal cortical proximal tubular epithelial cells were subjected to hypoxia and lipopolysaccharide for 72 h, with concurrent treatment using MZWT, FM19G11, and N-acetyl-l-cysteine. Measurements taken included reactive oxygen species (ROS), HIF pathway activity, inflammatory markers, and other relevant indicators. ResultsAde treatment induced significant disruptions in renal function, blood lipids, electrolytes, and tubulointerstitial architecture, alongside heightened OS, HIF pathway activation, and inflammatory responses in rats. In vivo, MZWT effectively ameliorated proteinuria, renal dysfunction, lipid and electrolyte imbalances, and renal tissue damage; it also suppressed OS, HIF pathway activation, epithelial-mesenchymal transition (EMT) in proximal tubular epithelial cells, and reduced the production of inflammatory cytokines and collagen fibers. In vitro findings demonstrated that MZWT decreased apoptosis, reduced ROS production, curbed OS, HIF pathway activation, and EMT in proximal tubular epithelial cells, and diminished the output of inflammatory cytokines and collagen. ConclusionOS and hypoxic responses significantly contribute to TIF development. MZWT mitigates these responses in renal proximal tubular epithelial cells, thereby delaying the progression of CRF.

Hyaluronidase inhibits TGF-β-mediated rat periodontal ligament fibroblast expression of collagen and myofibroblast markers: An in vitro exploration of periodontal tissue remodeling

ObjectiveTo determine the effect of hyaluronic acid (HA) degradation by hyaluronidase (HYAL) in inhibiting collagen fiber production by rat periodontal ligament cells (rPDLCs). DesignPrimary rPDLCs were isolated from the euthanized rats and used for in vitro experiments. The appropriate HYAL concentration was determined through CCK-8 testing for cytotoxicity detection and Alizarin red staining for mineralization detection. RT-qPCR and western blot assays were conducted to assess the effect of HYAL, with or without TGF-β, on generation of collagen fiber constituents and expression of actin alpha 2, smooth muscle (ACTA2) of rPDLCs. ResultsNeither cell proliferation nor mineralization were significantly affected by treatment with 4 U/mL HYAL. HYAL (4 U/mL) alone downregulated type I collagen fiber (Col1a1 and Col1a2) and Acta2 mRNA expression; however, ACTA2 and COL1 protein levels were only downregulated by HYAL treatment after TGF-β induction. ConclusionsTreatment of rPDLCs with HYAL can inhibit TGF-β-induced collagen matrix formation and myofibroblast transformation.

Evaluation of the wound healing efficacy of new antibacterial polymeric nanofiber based on polyethylene oxide coated with copper nanoparticles and defensin peptide: An in-vitro to in-vivo assessment

ObjectiveToday, designing nanofibers with antibacterial properties using electrospinning technology is one of the attractive approaches for wound healing. Methods& analysis: This study aims to fabricate a nanocomposite from polyethylene oxide (PEO) coated with copper nanoparticles (NPs) and defensin peptide with wound healing and antimicrobial properties in different ratios of CuNPs/defensin (2/0 mg), (1.5/0.5 mg), and (1/1 mg) in the fixed contain polymer (98 mg). Then, the nanofiber properties were investigated by SEM, tensile, DSC, and BET analysis. Also, the antibacterial properties against S. aureus and E. coli, antioxidant, and in-vivo wound healing effects and histological analysis of the designed nanocomposites were evaluated in rat models. ResultsOur SEM images showed that CuNPs and defensin were properly coated on the PEO surface. According to the tensile, DSC, and antibacterial analysis results, the most appropriate feature was related to CuNPs/defensin (1.5/0.5 mg), with maximum elasticity, heat resistance, and antibacterial activity. Furthermore, the designed nanocomposites showed the best performance as a wound closure agent by increasing dermis and epidermis volume density, stimulating fibroblast cells and collagen fiber production, and improving skin vessels. ConclusionAccording to our results, PEO nanofibers loaded with CuNPs and defensin have the best potential for wound healing, and they can be used as antibacterial materials in the textile, drug, and medical industries.

Ginsenoside Rh4 alleviates idiopathic pulmonary fibrosis by enhancing the CXCL9–CXCR3 axis

AbstractIdiopathic pulmonary fibrosis (IPF), often likened to a “tumor‐like disease,” proves more lethal than several malignancies. Although prior studies have demonstrated the lung‐protective efficacy of ginsenosides, the precise mechanism underlying their alleviative effect on IPF remains elusive. In this study, we validated the efficacy of the ginsenoside Rh4 in alleviating IPF and delved into the underlying mechanisms. Our data showed that Rh4 intervention significantly reduced mortality and hydroxyproline (HYP) content in mice. It also alleviated the pathological process of IPF by ameliorating phenomena such as alveolar wall thickening induced by IPF. In addition, in vitro cellular experiments confirmed that ginsenoside Rh4 was effective in alleviating transforming growth factor‐β1‐induced IPF model. Further analysis showed that ginsenoside Rh4 significantly reduced collagen fiber production and deposition while inhibiting the coagulation cascade signaling pathway. In addition, ginsenoside Rh4 inhibited the epithelial‐mesenchymal transition(EMT) pathway by promoting the CXCR3‐CXCL9 axis, which ultimately alleviated IPF. In conclusion, our data strongly suggest that ginsenoside Rh4 has the potential to be an innovative prophylactic drug against IPF.

Combined therapeutic strategy based on blocking the deleterious effects of AGEs for accelerating diabetic wound healing.

Diabetic foot ulcer is a serious complication of diabetes. Excessive accumulation of advanced glycation end products (AGEs) is one of the critical pathogenic factors in postponing diabetic wound healing. The main pathogenic mechanisms of AGEs include inducing cellular dysfunction, prolonging inflammatory response, increasing oxidative stress and reducing endogenous nitric oxide (NO) production. Combination therapy of blocking the deleterious effects of AGEs and supplementing exogenous NO is hypothesized to promote diabetic wound healing. Here, we presented nanoparticles/hydrogel composite dressings to co-delivery rosiglitazone and S-nitroso glutathione into the wound bed. The designed co-delivery system augmented the survival of fibroblasts, reduced oxidative stress levels, reversed the change of mitochondrial membrane potential and decreased the proinflammatory cytokine expression. Local sustained release of therapeutic agents significantly improved the wound healing of diabetic rats including increasing the wound closure rate, alleviating inflammation, promoting collagen fiber production and angiogenesis. Our finding indicated this local deliver strategy aimed at inhibiting the toxic effects of AGEs has great clinical potential for diabetic wound treatment.

Warming Yang Promoting Blood Circulation and Diuresis Alleviates Myocardial Damage by Inhibiting Collagen Fiber and Myocardial Fibrosis and Attenuating Mitochondria Signaling Pathway Mediated Apoptosis in Chronic Heart Failure Rats

Warming Yang promoting blood circulation and diuresis (WYPBD) has been proven effective in treating some diseases. This study aimed to evaluate therapeutic effect of WYPBD in treating chronic heart failure (CHF). CHF rats were established by intraperitoneally injecting doxorubicin (DOX). Therapeutic effects of WYPBD on cardiac function and hemodynamic parameters of myocardial tissues were analyzed. Collagen fiber production and myocardial fibrosis were evaluated. Transcriptions of COL1A1 gene, COL3A1 gene, and TGFB1 gene were evaluated with RT-PCR. Expression of BNP, AVP, PARP, caspase-3, and Bcl-2 in myocardial tissues were evaluated. TUNEL assay was used to identify apoptosis of cardiomyocytes. WYPBD alleviated degree of myocardial hypertrophy in CHF rats compared to the rats in CHF model group (P < 0.05). WYPBD significantly improved cardiac hemodynamics (increased LVEF and LVSF) of CHF rats compared to rats in the CHF model group (P < 0.05). WYPBD protected myocardial structure and inhibited collagen fiber production in myocardial tissues of CHF rats. WYPBD markedly decreased myocardial fibrosis mediators (Col1α, Col3α, TGF-β1) transcription in myocardial tissues of CHF rats compared to rats in CHF model group (P < 0.05). WYPBD significantly reduced BNP and AVP expression in myocardial tissues of CHF rats compared to rats in the CHF model group (P < 0.05). WYPBD markedly reduced the expression of PRAP and caspase-3, and increased Bcl-2 expression in myocardial tissues of CHF rats compared to rats in the CHF model group (P < 0.05). In conclusion, WYPBD alleviated CHF myocardial damage by inhibiting collagen fiber and myocardial fibrosis, attenuating apoptosis associated with the mitochondria signaling pathway of cardiomyocytes.

Ellagic acid protected the gingival tissue via fibroblast and epidermal growth factors in rats.

To investigate the effect of ellagic acid (EA) in gingival tissues injury in rats. Twenty rats were categorized into two groups. In burn group, an excisional wound area was created by removing a 4-mm diameter flap from the left molar region in the mucoperiosteal region of the gingiva. In burn + ellagic acid group, 1.2mg/mL EA was administered as irrigation for one week. Animals was sacrificed under anesthesia at the end of experiment. Malondialdehyde (MDA), myeloperoxidase (MPO) and glutathione (GSH) level were measured. Hematoxylin and eosin, fibroblast growth factor (FGF) and epidermal growth factor (EGF) immunostainings were applied to tissues. MDA, MPO, inflammation and leukocyte infiltration were high in burn group. Degeneration epithelium, edema and inflammatory cell infiltration in connective tissue areas, and dilatation and congestion in blood vessels were observed in burn group. In burn + EA group, the gingival epithelium improved, collagen fiber production increased and organized dermis were observed. After burn injury, FGF and EGF activity was increased in EA treated groups. We suggest that EA have the potential for better healing outcomes in oral wounds. EA seems to have promising therapeutic efficacy to enhance oral wound healing.

Inflammation-related signaling pathways in tendinopathy.

Tendon is a connective tissue that produces movement by transmitting the force produced by muscle contraction to the bones. Most tendinopathy is caused by prolonged overloading of the tendon, leading to degenerative disease of the tendon. When overloaded, the oxygen demand of tenocytes increases, and the tendon structure is special and lacks blood supply, which makes it easier to form an oxygen-deficient environment in tenocytes. The production of reactive oxygen species due to hypoxia causes elevation of inflammatory markers in the tendon, including PGE2, IL-1β, and TNF-α. In the process of tendon healing, inflammation is also a necessary stage. The inflammatory environment formed by cytokines and various immune cells play an important role in the clearance of necrotic material, the proliferation of tenocytes, and the production of collagen fibers. However, excessive inflammation can lead to tendon adhesions and hinder tendon healing. Some important and diverse biological functions of the body originate from intercellular signal transduction, among which cytokine mediation is an important way of signal transduction. In particular, NF-κB, NLRP3, p38/MAPK, and signal transducer and activator of transcription 3, four common signaling pathways in tendinopathy inflammatory response, play a crucial role in the regulation and transcription of inflammatory factors. Therefore, summarizing the specific mechanisms of inflammatory signaling pathways in tendinopathy is of great significance for an in-depth understanding of the inflammatory response process and exploring how to inhibit the harmful part of the inflammatory response and promote the beneficial part to improve the healing effect of the tendon.

Ellagic acid loaded nanospheres/biodegradable PVA‐sodium alginate hydrogel for wound healing application

AbstractIn the present study, a novel polyvinyl alcohol‐sodium alginate hydrogel was prepared using ellagic acid loaded nanospheres in its structure. Ellagic acid was loaded into polymeric nanospheres using a double‐emulsion solvent evaporation technique. Obtained nanospheres were dispersed in a polyvinyl alcohol‐sodium alginate hydrogel, prepared using freeze–thaw method followed by freeze‐drying. Ellagic acid loaded nanospheres and the final hydrogel preparation were characterized using scanning electron microscopy, dynamic light scattering, and Fourier transformation infrared spectroscopy, and investigated for ellagic acid content, and release profile. MTT assays were conducted to measure the viability of cells after treatment with the hydrogel, and wound healing activity was investigated through in vivo studies on open wounds of an animal model. Results showed formation of nanospheres with average diameter of 241.5 nm and prolonged‐release profile of ellagic acid during 48 h. MTT assays showed a significant increase in cell proliferation upon treatment of NIH3T3 cells with the hydrogel. The hydrogel also significantly increased the rate of wound closure through improved epithelialization and production of collagen fibers. It can be concluded that the hydrogel containing ellagic acid‐loaded nanospheres prepared in this study can be designated as a biocompatible dressing to accelerate the wound healing process.

Use of retinoids in the treatment of skin lesions and prevention of signs of skin aging - a systematic review

Retinoids are a group of substances that include vitamin A and its natural and synthetic derivatives. They are used in the treatment of various skin diseases, such as: rosacea, acne vulgaris, psoriasis. In addition, recently there is a lot of information about the action of preventing photoaging. Oral retinoids have been proven to be the most effective treatment for acne of various severity available today. Through their comprehensive action, affecting the four main factors associated with the pathogenesis of acne, they significantly reduce skin changes. Externally applied retinoids regulate the renewal of epidermal cells, stimulate the production of collagen fibers, increase the production of elastin, and lead to an increase in the number and activity of fibroblasts. Therefore, more and more people are using preparations containing retinoids to prevent skin aging. It has been proven that this procedure leads to shallower wrinkles and slows down the appearance of new ones, and evens out the skin tone. Retinoids are effective substances, but their use is associated with the risk of various side effects, the most common of which are: skin irritation, photosensitisation, headaches, muscle and joint pain, and teratogenicity.

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.