The myokine decorin improves the cardiac function in a rat model of isoprenaline-induced myocardial infarction.

Myocardial infarction is a common cause of disability. Decorin is a myokine that has anti-inflammatory, anti-apoptotic effects. Some studies stated that decorin protects myocardium from ischemia. Other studies stated that decorin levels are associated with acute coronary syndrome. The study aimed to investigate the therapeutic role of decorin on cardiac function in a rat model of myocardial infarction. Thirty adult male Wistar rats were divided into control group-rats were subcutaneously injected with normal saline, isoprenaline-injected group-rats were subcutaneously injected with isoprenaline (85 mg/kg) once daily for 2 days to induce myocardial infarction, and decorin ± isoprenaline-injected group-rats were injected as the previous group, followed by decorin injection (0.1 mg/kg) once daily for 7 days. Cardiac hemodynamics, serum lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB), oxidative stress markers, gene expression for myocardial-transforming growth factor beta 1 (TGF-ß1), interleukin 1 b (IL-1ß), tumor necrosis factor alpha (TNF-α), and cardiac caspase-3 immunohistochemical analysis were done. Isoprenaline + decorin group had significant improvement in cardiac hemodynamics and oxidative stress markers; significant decrease in serum CK-MB, LDH, and myocardial gene expression for TNF-α, IL-1ß, and TGF-ß1; and decreased cardiac caspase-3 immunoreactivity was present. Therefore, decorin can be used as a therapeutic agent after myocardial infarction as it improved the cardiac function.

Fractional carbon dioxide laser alone and as an assisted drug delivery for treatment of alopecia areata: a clinical, dermoscopic and immunohistochemical study.

Alopecia areata (AA) is a common cause of hair loss with no available universally successful treatment. Thus, new innovative treatments are urgently needed. This research aimed to evaluate the effectiveness of fractional carbon dioxide laser (FCL) alone or combined with triamcinolone acetonide (TA) solution, platelet-rich plasma (PRP), or vitamin D3 solution in treating AA. Sixty-four AA patients with 185 lesions were recruited and divided into four treatment groups. All patients received FCL either alone (group A, n = 19) or followed by topical TA (group B, n = 16) or PRP (group C, n = 15), or vitamin D3 solution (group D, n = 14). The response was assessed using Alopecia Areata Severity Index (AASI), MacDonald Hull and Norris grading, and trichoscopy. Histopathological features and immunohistochemical decorin expression were studied. All groups showed significant improvement in AASI compared to the baseline, with insignificant differences between them. Post-treatment, trichoscopic features of disease activity significantly decreased in all groups. Compared to control biopsies, both anagen follicles and decorin expression were significantly decreased in all pretreatment specimens. After treatment, all groups showed significantly increased anagen follicles and decorin expression compared to the baseline. Accordingly, FCL is an effective treatment for AA alone or combined with TA, PRP, or vitamin D3 solution. In AA, Decorin expression was downregulated, while enhanced expression following successful treatment occurred. This suggests the role of decorin in AA pathogenesis. However, further research is still recommended to clarify the exact role of decorin in AA pathogenesis and to investigate the therapeutic benefits of decorin-based therapy.

Is Decorin a Promising New Agent for Facial Nerve Regeneration? An Experimental Study.

OBJECTIVE: The aim of this study was to investigate the effects of systemic administration of decorin (DC) on facial nerve (FN) regeneration. METHODS: A total of 32 female albino Wistar rats were divided into 4 groups: control (C) group: no bilateral FN neurorrhaphy (B-FNN), no DC application, sham-operated group: B-FNN without DC application, DC group: DC application without B-FNN, and B-FNN + DC group: B-FNN and DC application. Nerve conduction studies were performed before and after skin incisions at 1st, 3rd, 5th, and 7th weeks in all groups. The amplitude and latency of compound muscle action potentials were recorded. FN samples were obtained and were investigated under light microscopy and immunohistochemical staining. The nerve and axon diameter, number of axons, H score, Schwann cell proliferation, and myelin and axonal degeneration were recorded quantitatively. RESULTS: In the sham group, the 3rd and 5th postoperative week, amplitude values were significantly lower than those of the B-FNN + DC group (p < 0.05). Nerve diameters were found to be significantly larger in the sham, DC, and B-FNN + DC groups than in the C group (p < 0.05). The number of axons, the axon diameter, and the H scores were found to be significantly higher in the B-FNN + DC group than in the sham group (p < 0.05). The Schwann cell proliferation, myelin degeneration, and axonal degeneration scores were significantly lower in the B-FNN + DC group than in the sham group (p < 0.05). CONCLUSION: Electrophysiological and histopathological evaluation revealed the potential benefits provided by DC. This agent may increase FN regeneration.

Muscle Resting and TGF-ß Inhibitor Treatment Prevent Fatty Infiltration Following Skeletal Muscle Injury.

BACKGROUND/AIMS: Skeletal muscle injuries are the most common type of injury occurring in sports, and investigating skeletal muscle regeneration as well as understanding the related processes is an important aspect of the sports medicine field. The process of regeneration appears to be complex and precisely orchestrated, involving fibro-adipogenic progenitors (FAPs) which are a muscle-resident stem cell population that appears to play a major role in abnormal development of fibrotic tissue or intermuscular adipose tissue (IMAT). Our present study aims to investigate whether muscle resting or endurance exercise following muscle injury may change the behavior of FAPs and subsequently impact the development of fatty infiltrations and fibrosis, two hallmarks of regeneration failure. METHODS: We used the validated glycerol muscle injury model to mimic abnormal muscle regenerative conditions in mice. We challenged this specific regeneration model with hindlimb unloading or endurance exercise and, in a second set of experiments, we treated mice with decorin, a TGF-ß inhibitor. RESULTS: In this study, we demonstrated that: i) muscle resting just after injury leads to inhibition of IMAT development, ii) TNF-α mediated FAP apoptosis might be perturbed in this specific glycerol model of muscle injury, leading to IMAT development, and iii) treatment with the TGF-ß inhibitor decorin decreases IMAT development and might restores FAP apoptosis. CONCLUSION: In addition to the potential clinical relevance of decorin treatment in situations involving muscle plasticity and regeneration, this study also demonstrates that a period of muscle resting is necessary following muscle injury to achieve efficient muscle regeneration which is associated with a reduction in fatty infiltration. Unreasonably early resumption of exercise brings no gain to regeneration, further highlighting that this resting period is necessary.

Natural healing-inspired collagen-targeting surgical protein glue for accelerated scarless skin regeneration.

Skin scarring after deep dermal injuries is a major clinical problem due to the current therapies limited to established scars with poor understanding of healing mechanisms. From investigation of aberrations within the extracellular matrix involved in pathophysiologic scarring, it was revealed that one of the main factors responsible for impaired healing is abnormal collagen reorganization. Here, inspired by the fundamental roles of decorin, a collagen-targeting proteoglycan, in collagen remodeling, we created a scar-preventive collagen-targeting glue consisting of a newly designed collagen-binding mussel adhesive protein and a specific glycosaminoglycan. The collagen-targeting glue specifically bound to type I collagen in a dose-dependent manner and regulated the rate and the degree of fibrillogenesis. In a rat skin excisional model, the collagen-targeting glue successfully accelerated initial wound regeneration as defined by effective reepithelialization, neovascularization, and rapid collagen synthesis. Moreover, the improved dermal collagen architecture was demonstrated by uniform size of collagen fibrils, their regular packing, and a restoration of healthy tissue component. Collectively, our natural healing-inspired collagen-targeting glue may be a promising therapeutic option for improving the healing rate with high-quality and effective scar inhibition.

The histopathological and pharmacodynamic effects of intradetrusor decorin injected in a rabbit partial bladder outlet obstruction model.

PURPOSE: To evaluate whether or not the bladder function can be protected by supporting the detrusor with decorin levels during the fibrotic process. METHODS: Forty-two male rabbits were divided into three main groups, partial bladder outlet obstruction (pBOO) group, pBOO + intradetrusor decorin-injected (IDI) group and control group. Both pBOO and pBOO + IDI groups were divided into three subgroups according to the killing schedule. Histopathological, immunohistochemical and pharmacodynamics studies were performed for the evaluation of fibrotic process and tissue characteristics. RESULTS: Histopathological evaluation revealed statistically significant high fibrosis levels for both pBOO and pBOO + IDI groups when compared with control. Strikingly the antifibrotic effect of decorin was significant on 2nd, 4th and 8th week and increased as time passed. Immunohistochemical analysis was revealed high expressions of anti-TGF-ß1 and decorin levels in all pBOO + IDI groups. Pharmacodynamical results were also revealed better contraction responses in favor of 2nd, 4th and 8th week groups of pBOO + IDI groups, when compared with pBOO groups. In addition, the contraction responses against the depolarizer agent KCl were increased in the three decorin-administrated groups. CONCLUSION: Our study demonstrates the antifibrotic effects of decorin on bladder fibrosis. Strikingly, this antifibrotic effect is shown in histopathological, immunohistochemical and pharmacodynamics studies. Although further studies are warranted to make more decisive inferences regarding its clinical use, our study has the proper pride to be the first step of this time course.

Chondroitin Sulfate- and Decorin-Based Self-Assembling Scaffolds for Cartilage Tissue Engineering.

Cartilage injury and degenerative tissue progression remain poorly understood by the medical community. Therefore, various tissue engineering strategies aim to recover areas of damaged cartilage by using non-traditional approaches. To this end, the use of biomimetic scaffolds for recreating the complex in vivo cartilage microenvironment has become of increasing interest in the field. In the present study, we report the development of two novel biomaterials for cartilage tissue engineering (CTE) with bioactive motifs, aiming to emulate the native cartilage extracellular matrix (ECM). We employed a simple mixture of the self-assembling peptide RAD16-I with either Chondroitin Sulfate (CS) or Decorin molecules, taking advantage of the versatility of RAD16-I. After evaluating the structural stability of the bi-component scaffolds at a physiological pH, we characterized these materials using two different in vitro assessments: re-differentiation of human articular chondrocytes (AC) and induction of human adipose derived stem cells (ADSC) to a chondrogenic commitment. Interestingly, differences in cellular morphology and viability were observed between cell types and culture conditions (control and chondrogenic). In addition, both cell types underwent a chondrogenic commitment under inductive media conditions, and this did not occur under control conditions. Remarkably, the synthesis of important ECM constituents of mature cartilage, such as type II collagen and proteoglycans, was confirmed by gene and protein expression analyses and toluidine blue staining. Furthermore, the viscoelastic behavior of ADSC constructs after 4 weeks of culture was more similar to that of native articular cartilage than to that of AC constructs. Altogether, this comparative study between two cell types demonstrates the versatility of our novel biomaterials and suggests a potential 3D culture system suitable for promoting chondrogenic differentiation.

Decorin Reduces Intraocular Pressure and Retinal Ganglion Cell Loss in Rodents Through Fibrolysis of the Scarred Trabecular Meshwork.

PURPOSE: To investigate whether Decorin, a matrikine that regulates extracellular matrix (ECM) deposition, can reverse established trabecular meshwork (TM) fibrosis, lower IOP, and reduce progressive retinal ganglion cell (RGC) death in a novel rodent model of TM fibrosis. METHODS: Adult rats had intracameral (IC) injections of human recombinant (hr) TGF-ß over 30 days (30 d; to induce TM fibrosis, raise IOP, and initiate RGC death by 17 d) or PBS (controls) and visually evoked potentials (VEP) were measured at 30 d to evaluate resultant visual pathway dysfunction. In some animals TGF-ß injections were stopped at 17 d when TM fibrosis and IOP were consistently raised and either hrDecorin or PBS IC injections were administered between 21 d and 30 d. Intraocular pressure was measured biweekly and eyes were processed for immunohistochemical analysis of ECM deposition to assess TM fibrosis and levels of matrix metalloproteinases (MMP) and tissue inhibitors of matrix metalloproteinases (TIMP) to assess fibrolysis. The effect of hrDecorin treatment on RGC survival was also assessed. RESULTS: Transforming growth factor-ß injections caused sustained increases in ECM deposition in the TM and raised IOP by 17 d, responses that were associated with 42% RGC loss and a significant decrease in VEP amplitude measured at 30 d. Decorin treatment from 17 d reduced TGF-ß-induced TM fibrosis, increased levels of MMP2 and MMP9 and lowered TIMP2 levels, and lowered IOP, preventing progressive RGC loss. CONCLUSIONS: Human recombinant Decorin reversed established TM fibrosis and lowered IOP, thereby rescuing RGC from progressive death. These data provide evidence for the candidacy of hrDecorin as a treatment for open-angle glaucoma.

Decorin-expressing adenovirus decreases collagen synthesis and upregulates MMP expression in keloid fibroblasts and keloid spheroids.

Decorin is a natural transforming growth factor-ß1 (TGF-ß1) antagonist. Reduced decorin synthesis is associated with dermal scarring, and increased decorin expression appears to reduce scar tissue formation. To investigate the therapeutic potential of decorin for keloids, human dermal fibroblasts (HDFs) and keloid-derived fibroblasts (KFs) were transduced with decorin-expressing adenovirus (dE1-RGD/GFP/DCN), and we examined the therapeutic potential of decorin-expressing Ad for treating pathologic skin fibrosis. Decorin expression was examined by immunofluorescence assay on keloid tissues. HDFs and KFs were transduced with dE1-RGD/GFP/DCN or control virus, and protein levels of decorin, epidermal growth factor receptor (EGFR) and secreted TGF-ß1 were assessed by Western blotting and ELISA. And type I and III collagen, and matrix metalloproteinase-1 (MMP-1) and matrix metalloproteinase-3 (MMP-3) mRNA levels were measured by real-time RT-PCR. Additionally, we immunohistochemically investigated the expression levels of the major extracellular matrix (ECM) proteins in keloid spheroids transduced with dE1-RGD/GFP/DCN. Lower decorin expression was observed in the keloid region compared to adjacent normal tissues. After treatment with dE1-RGD/GFP/DCN, secreted TGF-ß1 and EGFR protein expressions were decreased in TGF-ß1-treated HDFs and KFs. Also, type I and III collagen mRNA levels were decreased, and the expression of MMP-1 and MMP-3 mRNA was strongly upregulated. In addition, the expression of type I and III collagen, fibronectin and elastin was significantly reduced in dE1-RGD/GFP/DCN-transduced keloid spheroids. These results support the utility of decorin-expressing adenovirus to reduce collagen synthesis in KFs and keloid spheroid, which may be highly beneficial in treating keloids.

Decorin accelerates the liver regeneration after partial hepatectomy in fibrotic mice.

BACKGROUND: Considering the existence of a large number of liver cell degeneration and necrosis in fibrotic liver, liver function was damaged severely and could not effectively regenerate after partial hepatectomy (PHx). The aim of this study was to investigate whether decorin (DCN) could promote the liver regeneration after PHx in fibrotic mice. METHODS: Forty mice (5-week-old, Balb/c) were injected with CCl4 intraperitoneally and liver fibrosis model was established after 5 weeks. The survival mice were randomly divided into two groups: control group and DCN group. Then, we performed 70% PHx on all these mice and injected DCN or phosphate-buffered saline plus normal saline (NS) to each group, respectively, after surgery. Liver body weight ratio (LBR), quantitative real-time polymerase chain reaction, and immunohistochemistry were used to analyze liver regeneration and fibrosis degree in both groups, and to find out whether exogenous protein DCN could promote the regeneration of fibrosis liver after PHx. RESULTS: Expressions of a-smooth muscle actin (SMA) mRNA and LBR had significant increases in the DCN group at postoperative Day 3 (POD 3, P < 0.05). The protein expressions of CD31, a-SMA, and tumor necrosis factor (TNF)-a were higher in the DCN group than those in the control group by immunohistochemistry at POD 3 (P < 0.05). CONCLUSION: Exogenous protein DCN could promote liver regeneration after PHx in fibrotic mice.

Decorin prevents the development of CCl4-induced liver fibrosis in mice.

BACKGROUND: Liver fibrosis normally progresses to cirrhosis and destroys the normal architecture of the liver, resulting in liver dysfunction and irreversible cirrhosis. The aim of this study was to investigate the anti-fibrosis effect and the possible underlying mechanisms of decorin. METHODS: The mice model of liver fibrosis was induced by intraperitoneal injection of 50% (v/v) of carbon tetrachloride (CCl4) diluted in olive oil (1 ml/kg body weight) once every 2 days for 5 weeks. Three weeks after injecting CCl4 intraperitoneally, mice were randomly divided into normal control with vehicles only (olive oil), mouse model given CCl4 only, and CCl4 plus decorin (DCN, 250 µg/kg). Two weeks later, all the mice were sacrificed and their liver tissues were analyzed for the expressions of genes related to liver fibrosis and under hematoxylin-eosin staining, Masson staining, and immunohistochemical staining of all groups. Aspartate transaminase, alanine transaminase, and total bilirubin of the serum were determined for evaluation of the liver function. RESULTS: Exogenous protein decorin could reduce liver fibrosis induced by CCl4 in mice. The degree of fibrosis in the experimental group was alleviated, and the contents of collagen fibers were lower in the experimental group than those of the control group. In addition, expressions of transforming growth factor ß1 and α-smooth muscle actin decreased in the experimental group. CONCLUSIONS: Taking liver fibrosis model of mouse as the experimental target and by injecting exogenous protein decorin into the model, we confirmed that decorin could inhibit the expression of proteins related to fibrosis and reduce the formation of liver fibrosis in mice.

Use of decorin to prevent epidural fibrosis in a post-laminectomy rat model.

The formation of epidural fibrosis adjacent to the dura mater is a complex multi-step process that is associated with a marked reduction in tissue cellularity and the excessive deposition of extracellular matrix components. Extensive epidural fibrosis is a major cause of post-laminectomy syndrome. Decorin strongly inhibits fibrosis formation in various tissues via blockade of transforming growth factor-ß1. The aim of this study was to investigate the effects of a topical application of decorin on the formation of epidural fibrosis in a rat laminectomy model. Twenty-four female Wistar albino rats (250-350 g) were equally and randomly divided into three groups (control, spongostan and decorin). Laminectomy was performed between the L3 and L5 levels in all rats. The dura mater was directly exposed to spongostan soaked with saline (2 cc/kg) or decorin (100 µg/kg). Four weeks later, the laminectomized spine of the rats was completely removed between the L3 and L5 levels. The extent of the epidural fibrosis and arachnoidal involvement was histopathologically evaluated and graded. Our data revealed that epidural fibrosis was significantly reduced in the group treated with decorin compared to the spongostan and control groups (P<0.05). Our study demonstrates that the topical application of decorin can be effective in reducing the formation of epidural fibrosis in a simple laminectomy rat model.

Decorin prevents the development of juvenile communicating hydrocephalus.

In post-haemorrhagic and other forms of communicating hydrocephalus, cerebrospinal fluid flow and drainage is obstructed by subarachnoid fibrosis in which the potent fibrogenic cytokine transforming growth factor-ß has been aetiologically implicated. Here, the hypothesis that the transforming growth factor-ß antagonist decorin has therapeutic potential for reducing fibrosis and ventriculomegaly was tested using a rat model of juvenile communicating hydrocephalus. Hydrocephalus was induced by a single basal cistern injection of kaolin in 3-week-old rats, immediately followed by 3 or 14 days of continuous intraventricular infusion of either human recombinant decorin or phosphate-buffered saline (vehicle). Ventricular expansion was measured by magnetic resonance imaging at Day 14. Fibrosis, transforming growth factor-ß/Smad2/3 activation and hydrocephalic brain pathology were evaluated at Day 14 and the inflammatory response at Days 3 and 14 by immunohistochemistry and basic histology. Analysis of ventricular size demonstrated the development of hydrocephalus in kaolin-injected rats but also revealed that continuous decorin infusion prevented ventricular enlargement, such that ventricle size remained similar to that in intact control rats. Decorin prevented the increase in transforming growth factor-ß1 and phosphorylated Smad2/3 levels throughout the ventricular system after kaolin injection and also inhibited the deposition of the extracellular matrix molecules, laminin and fibronectin in the subarachnoid space. In addition, decorin protected against hydrocephalic brain damage inferred from attenuation of glial and inflammatory reactions. Thus, we conclude that decorin prevented the development of hydrocephalus in juvenile rats by blocking transforming growth factor-ß-induced subarachnoid fibrosis and protected against hydrocephalic brain damage. The results suggest that decorin is a potential clinical therapeutic for the treatment of juvenile post-haemorrhagic communicating hydrocephalus.

A comparison of the behavioral and anatomical outcomes in sub-acute and chronic spinal cord injury models following treatment with human mesenchymal precursor cell transplantation and recombinant decorin.

This study assessed the potential of highly purified (Stro-1(+)) human mesenchymal precursor cells (hMPCs) in combination with the anti-scarring protein decorin to repair the injured spinal cord (SC). Donor hMPCs isolated from spinal cord injury (SCI) patients were transplanted into athymic rats as a suspension graft, alone or after previous treatment with, core (decorin(core)) and proteoglycan (decorin(pro)) isoforms of purified human recombinant decorin. Decorin was delivered via mini-osmotic pumps for 14 days following sub-acute (7 day) or chronic (1 month) SCI. hMPCs were delivered to the spinal cord at 3 weeks or 6 weeks after the initial injury at T9 level. Behavioral and anatomical analysis in this study showed statistically significant improvement in functional recovery, tissue sparing and cyst volume reduction following hMPC therapy. The combination of decorin infusion followed by hMPC therapy did not improve these measured outcomes over the use of cell therapy alone, in either sub-acute or chronic SCI regimes. However, decorin infusion did improve tissue sparing, reduce spinal tissue cavitation and increase transplanted cell survivability as compared to controls. Immunohistochemical analysis of spinal cord sections revealed differences in glial, neuronal and extracellular matrix molecule expression within each experimental group. hMPC transplanted spinal cords showed the increased presence of serotonergic (5-HT) and sensory (CGRP) axonal growth within and surrounding transplanted hMPCs for up to 2 months; however, no evidence of hMPC transdifferentiation into neuronal or glial phenotypes. The number of hMPCs was dramatically reduced overall, and no transplanted cells were detected at 8 weeks post-injection using lentiviral GFP labeling and human nuclear antigen antibody labeling. The presence of recombinant decorin in the cell transplantation regimes delayed in part the loss of donor cells, with small numbers remaining at 2 months after transplantation. In vitro co-culture experiments with embryonic dorsal root ganglion explants revealed the growth promoting properties of hMPCs. Decorin did not increase axonal outgrowth from that achieved by hMPCs. We provide evidence for the first time that (Stro-1(+)) hMPCs provide: i) an advantageous source of allografts for stem cell transplantation for sub-acute and chronic spinal cord therapy, and (ii) a positive host microenvironment that promotes tissue sparing/repair that subsequently improves behavioral outcomes after SCI. This was not measurably improved by recombinant decorin treatment, but does provide important information for the future development and potential use of decorin in contusive SCI therapy.

Duchenne muscular dystrophy fibroblast nodules: a cell-based assay for screening anti-fibrotic agents.

Severe muscle fibrosis is the endpoint of many chronic myopathies. Identification of factors that regulate fibrosis is important for understanding its pathogenesis and for developing anti-fibrotic treatments that prevent muscle destruction. We have developed an in vitro model for screening potential anti-fibrotic agents. The model consists of three-dimensional clusters (nodules) of fibroblasts derived from Duchenne muscular dystrophy (DMD) muscle. The primary fibroblasts spontaneously and quickly form nodules resembling fibrotic foci (cells plus extracellular matrix) when grown on a solid substrate. We tested the anti-fibrotic action of suramin, decorin, and spironolactone (all with established anti-fibrotic activity) on the model. All three agents significantly reduced nodule number, and spironolactone and suramin significantly reduced nodule diameter. Nodule secretion of soluble collagen was also significantly reduced by decorin and spironolactone treatment, whereas suramin had no significant effect. Collagen I and fibronectin protein expression was significantly reduced in the culture medium of control and DMD fibroblasts by spironolactone treatment, but not by decorin and suramin treatment. Finally, in DMD fibroblast monolayers, collagen deposition was significantly reduced by all three agents. Spironolactone significantly reduced collagen I and fibronectin transcript levels, whereas decorin reduced only fibronectin. Our in vitro model of fibrogenesis has thus revealed differing anti-fibrotic effects in the three anti-fibrotic agents tested. It therefore appears as a useful and sensitive system for the testing of anti-fibrotic drugs and could be adapted for the high-throughput screening of new anti-fibrotic molecules.

Decorin as a new treatment alternative in Peyronie's disease: preliminary results in the rat model.

The purpose of this study is to investigate the effect of decorin, a naturally occurring proteoglycan with anti-transforming growth factor beta (TGF-ß) activity, on the rat model of Peyronie's disease (PD). Twenty-five adult male Sprague-Dawley rats were divided in three groups: I) TGF-ß (0.5 µg) injected (n: 8); II) TGF-ß injected and decorin treated (n: 8); and III) controls (n: 9). Decorin (0.5 µg per day) was given with intracavernous injection on the second, third, fourth and fifth day following TGF-ß injection. All rats underwent electrical stimulation of the cavernous nerve after 6 weeks. Intracavernosal and arterial blood pressures were measured during this procedure. Cross-sections of the rat penises were examined using Mason trichrome and H&E stains. Statistical analyses were carried out using one-way anova. Histopathological examinations confirmed the Peyronie's-like condition in TGF-ß-injected rats, which exhibited a thickening of the tunica albuginea (TA), when compared to controls. Disorganisation of collagen on the TA was also prominent in TGF-ß-injected rats, but not in decorin-treated and control rats. Decorin-treated rats showed significantly higher maximal intracavernosal pressure (MIP) responses to cavernous nerve stimulation, when compared to group 1 (P < 0.05). Our results indicate that decorin antagonises the effects of TGF-ß in the rat model of PD and prevents diminished erectile response to cavernous nerve stimulation.

Decorin antagonizes the angiogenic network: concurrent inhibition of Met, hypoxia inducible factor 1α, vascular endothelial growth factor A, and induction of thrombospondin-1 and TIMP3.

Decorin, a small leucine-rich proteoglycan, inhibits tumor growth by antagonizing multiple receptor tyrosine kinases including EGFR and Met. Here, we investigated decorin during normoxic angiogenic signaling. An angiogenic PCR array revealed a profound decorin-evoked transcriptional inhibition of pro-angiogenic genes, such as HIF1A. Decorin evoked a reduction of hypoxia inducible factor (HIF)-1α and vascular endothelial growth factor A (VEGFA) in MDA-231 breast carcinoma cells expressing constitutively-active HIF-1α. Suppression of Met with decorin or siRNA evoked a similar reduction of VEGFA by attenuating downstream ß-catenin signaling. These data establish a noncanonical role for ß-catenin in regulating VEGFA expression. We found that exogenous decorin induced expression of thrombospondin-1 and TIMP3, two powerful angiostatic agents. In contrast, decorin suppressed both the expression and enzymatic activity of matrix metalloprotease (MMP)-9 and MMP-2, two pro-angiogenic proteases. Our data establish a novel duality for decorin as a suppressor of tumor angiogenesis under normoxia by simultaneously down-regulating potent pro-angiogenic factors and inducing endogenous anti-angiogenic agents.

Targeted decorin gene therapy delivered with adeno-associated virus effectively retards corneal neovascularization in vivo.

Decorin, small leucine-rich proteoglycan, has been shown to modulate angiogenesis in nonocular tissues. This study tested a hypothesis that tissue-selective targeted decorin gene therapy delivered to the rabbit stroma with adeno-associated virus serotype 5 (AAV5) impedes corneal neovascularization (CNV) in vivo without significant side effects. An established rabbit CNV model was used. Targeted decorin gene therapy in the rabbit stroma was delivered with a single topical AAV5 titer (100 µl; 5×10(12) vg/ml) application onto the stroma for two minutes after removing corneal epithelium. The levels of CNV were examined with stereomicroscopy, H&E staining, lectin, collagen type IV, CD31 immunocytochemistry and CD31 immunoblotting. Real-time PCR quantified mRNA expression of pro- and anti-angiogenic genes. Corneal health in live animals was monitored with clinical, slit-lamp and optical coherence tomography biomicroscopic examinations. Selective decorin delivery into stroma showed significant 52% (p<0.05), 66% (p<0.001), and 63% (p<0.01) reduction at early (day 5), mid (day 10), and late (day 14) stages of CNV in decorin-delivered rabbit corneas compared to control (no decorin delivered) corneas in morphometric analysis. The H&E staining, lectin, collagen type IV, CD31 immunostaining (57-65, p<0.5), and CD31 immunoblotting (62-67%, p<0.05) supported morphometric findings. Quantitative PCR studies demonstrated decorin gene therapy down-regulated expression of VEGF, MCP1 and angiopoietin (pro-angiogenic) and up-regulated PEDF (anti-angiogenic) genes. The clinical, biomicroscopy and transmission electron microscopy studies revealed that AAV5-mediated decorin gene therapy is safe for the cornea. Tissue-targeted AAV5-mediated decorin gene therapy decreases CNV with no major side effects, and could potentially be used for treating patients.

The novel use of decorin in prevention of the development of proliferative vitreoretinopathy (PVR).

BACKGROUND: The cytokine transforming growth factor-ß (TGF-ß) is a pivotal contributor to tissue fibrosis and a key cytokine in the pathogenesis of cellular transdifferentiation, epithelial-mesenchymal transition (EMT), and cell adhesion. This study evaluates the effect of decorin, a naturally occurring TGF-ß inhibitor, in an experimental rabbit model for proliferative vitreoretinopathy (PVR). METHODS: Traumatic PVR was induced in 50 rabbits divided into ten groups (n = 5). One group (GI) reveals a control with no treatment after trauma. Groups (GII-GIV) consisted of subgroups receiving phacovitrectomy at three different time points; (a) at the time of trauma, (b) 1 week following trauma, and (c) 2 weeks following trauma. GIII and GIV received 100 µg or 200 µg decorin, respectively. PVR severity was scored from 0 to 4. The amount of fibrosis was quantified using JMicroVision© software. RESULTS: The control group GI developed severe PVR with tractional retinal detachment (TRD); (PVR score ≥2) in four rabbits out of five. Vitrectomy had a positive effect (p < 0.05) on PVR development when preformed immediately, however the developed fibrosis was high. The best results were obtained when surgery was used in conjunction with decorin that reduced both the PVR score and fibrosis development significantly (p < 0.05). Depending on dosage and time of vitrectomy, PVR could be completely avoided (PVR score = 0) in 16 rabbits out of 30. TRD was prevented in 13 rabbits out of 15 in GIII to 14 rabbits out of 15 in GIV. In decorin-treated eyes, vitrectomy outcome was best when preformed at 1 week after trauma. There were no drug-related toxic effects evident on clinical and histopathological examination. CONCLUSIONS: In conclusion, in this rabbit model of PVR, adjuvant decorin application during vitrectomy effectively reduces fibrosis and TRD development. In conjunction with no obvious histopathological toxicity signs, decorin represents a promising substance to inhibit PVR reactions.