Matrix metalloproteinase-2, -7, and -9 activities in dogs with idiopathic pulmonary fibrosis compared to healthy dogs and dogs with other respiratory diseases

Urine-Derived Stem Cells Reverse Bleomycin‑Induced Experimental Pulmonary Fibrosis by Inhibition of the TGF-β1-Smad2/3 Pathway

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is characterized by progressive lung interstitial lesions with the disease pathophysiology incompletely understood, which is a serious and fatal disorder with limited treatment options. Mesenchymal stem cells (MSCs) have exhibited promising therapeutic capability for IPF. While most types of MSCs are obtained invasively, urine-derived stem cells (USCs) can be gained in a safe, noninvasive, and inexpensive procedure, which are readily available and reported to exhibit no risk of teratoma formation or oncogenic potential in vivo, sounding alternative to other MSCs. This study aims to investigate the therapeutic effect and mechanism of USCs on IPF, using a bleomycin (BLM)-induced IPF model in mice.

METHODS

Cell surface marker examination by flow cytometry analysis and cell differentiation culture were used to characterize USCs obtained from healthy individuals. BLM was instilled endotracheally in adult C57BL/6 mice, followed by USCs or human bone marrow-derived mesenchymal stem cells (BMSCs) treatment by tail vein injection on day 14. Mice were euthanized on day 14 before administration or day 21 for the evaluation of pulmonary histopathology and hydroxyproline (HYP) content. Inflammatory factors of the lung, including transforming growth factor (TGF)-β1, TNF-α, IL-6, MMP2 were analyzed by quantitative real-time PCR (qRT-PCR). Additionally, immunohistochemistry (IHC) and western blotting (WB) were applied to evaluate the expression of α-SMA and activation of TGF-β1-Smad2/3 in lung.

RESULTS

USCs highly expressed CD29 and CD90, showing negative expression of hematopoietic stem cell markers (CD45, CD34) and could differentiate into, at least, bone and fat in vitro. In mice challenged with BLM, septal thickening and prominent fibrosis were observed on day 14, with higher HYP content and mRNA levels of TGF-β1, TNF-α and IL-6 exhibited, compared to untreated mice. USCs could migrate to lung and accumulate there in mouse model after intravenous injection. Transplantation of USCs into BLM-induced mice improved their pulmonary histopathology, decreasing Ashcroft score, Szapiel score, HYP content and mRNA levels of TGF-β1 and MMP2 of lung, similar to the effects of BMSCs. IHC and WB further revealed that USCs could inhibit activation of the TGF‑β1-Smad2/3 pathway of lung in vivo.

CONCLUSIONS

Transplantation of USCs effectively reverses pulmonary fibrotic phenotype in an experimental IPF model, inhibiting the TGF-β1-Smad2/3 pathway, a key driver of fibrosis. These results suggest the therapeutic application of USCs for IPF, instead of other types of MSCs obtained invasively.

Assessment of MMP-9 and clinical characteristics in dogs with tracheal collapse based on cough severity and fluoroscopic findings: a cross-sectional study

BACKGROUND

Tracheal collapse (TC), a common disease in dogs, is characterized by cough; however, little is known about the serum biomarkers that can objectively evaluate the severity of cough in canine TC. Furthermore, studies elucidating the relationship of fluoroscopic characteristics with the severity of cough are lacking. Therefore, this study aimed to evaluate the relationship between cough severity and clinical characteristics, fluoroscopic images, and new serum biomarkers in canine TC.

RESULTS

Fifty-one client-owned dogs diagnosed with TC based on fluoroscopic and clinical signs were enrolled in this study and divided into three groups according to the severity of cough (grade of cough: 0, 1, and 2). Signalments, comorbidities, and fluoroscopic characteristics were compared among the groups retrospectively. The serum matrix metalloproteinase-9 (MMP-9), interleukin-6 (IL-6), surfactant protein-A (SP-A), and syndecan-1 (SDC-1) levels were measured in all groups. No significant differences in age, breed, sex, or clinical history were observed among the groups. Concomitant pharyngeal collapse increased significantly with the severity of cough (p = .031). Based on the fluoroscopic characteristics, the TC grade of the carinal region increased significantly and consistently with the grade of cough (p = .03). The serum MMP-9 level was significantly higher in the grade 2 group than that in the grade 0 group (p = .014). The serum IL-6 level was significantly lower in the grade 1 group than that in the grade 0 group (p = .020). The serum SP-A and SDC-1 levels did not differ significantly among the groups.

CONCLUSIONS

The severity of cough with the progression of TC can be predicted with the fluoroscopic TC grade at the carinal region. MMP-9 may be used as an objective serum biomarker that represents cough severity to understand the pathogenesis.

Osteopontin and fibronectin in lung tissue, serum, and bronchoalveolar lavage fluid of dogs with idiopathic pulmonary fibrosis and control dogs

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) affects West Highland white terriers (WHWTs). Osteopontin (SPP1) and fibronectin (FN1) are associated with human IPF and are overexpressed by bronchoalveolar lavage fluid (BALF) macrophages in dogs with IPF.

OBJECTIVE

To investigate the value of these proteins as biomarkers of IPF.

ANIMALS

West Highland white terriers (WHWTs) with IPF, control WHWTs, and terriers.

METHODS

Cross-sectional observational study. Immunohistochemistry was used to localize SPP1 and FN1 in lung tissue. Serum and BALF SPP1 and FN1 concentrations were measured using canine ELISA kits and compared between groups.

RESULTS

Osteopontin stained ciliated epithelial cells, smooth muscular cells, and macrophages of all included dogs, and type-II pneumocytes and extracellular matrix of all 12 diseased WHWTs, 4/6 control WHWTs, and none of the 3 terriers. Osteopontin serum concentration was higher in diseased WHWTs (n = 22; 2.15 ng/mL [0.74-5.30]) compared with control WHWTs (n = 13; 0.63 ng/mL [0.41-1.63]; P = .005) and terriers (n = 15; 0.31 ng/mL [0.19-0.51]; P < .0001), and in control WHWTs compared with terriers (P = .005). Osteopontin BALF concentrations were higher in diseased (0.27 ng/mL [0.14-0.43]) and control WHWTs (0.25 ng/mL [0.14-0.40]), compared with terriers (0.02 ng/mL [0.01-0.08]; P < .0001 and P = .003, respectively). Fibronectin (FN1) serum concentrations were lower in diseased dogs (1.03 ng/mL [0.35-1.48]) and control WHWTs (0.61 ng/mL [0.24-0.65]) compared with terriers (2.72 ng/mL [0.15-5.21]; P < .0001 and P = .0001, respectively). There was no difference in FN1 immunostaining and FN1 BALF concentrations between groups.

CONCLUSIONS

Results suggest that SPP1 is involved in pathogenesis of IPF and could predispose that breed to the disease. Osteopontin serum concentration could serve as a diagnostic biomarker of IPF.

Amelioration of Pulmonary Fibrosis by Matrix Metalloproteinase-2 Overexpression

Idiopathic pulmonary fibrosis is a progressive and fatal disease with a poor prognosis. Matrix metalloproteinase-2 is involved in the pathogenesis of organ fibrosis. The role of matrix metalloproteinase-2 in lung fibrosis is unclear. This study evaluated whether overexpression of matrix metalloproteinase-2 affects the development of pulmonary fibrosis. Lung fibrosis was induced by bleomycin in wild-type mice and transgenic mice overexpressing human matrix metalloproteinase-2. Mice expressing human matrix metalloproteinase-2 showed significantly decreased infiltration of inflammatory cells and inflammatory and fibrotic cytokines in the lungs compared to wild-type mice after induction of lung injury and fibrosis with bleomycin. The computed tomography score, Ashcroft score of fibrosis, and lung collagen deposition were significantly reduced in human matrix metalloproteinase transgenic mice compared to wild-type mice. The expression of anti-apoptotic genes was significantly increased, while caspase-3 activity was significantly reduced in the lungs of matrix metalloproteinase-2 transgenic mice compared to wild-type mice. Active matrix metalloproteinase-2 significantly decreased bleomycin-induced apoptosis in alveolar epithelial cells. Matrix metalloproteinase-2 appears to protect against pulmonary fibrosis by inhibiting apoptosis of lung epithelial cells.

A rapid, selective, and ultrasensitive voltammetric and gravimetric protocol for MMP-1 active form detection

In this paper a rapid, selective, and ultrasensitive protocol for the detection of the active form of matrix metalloproteinase-1 (MMP-1), which is a novel predictive and prognostic biomarker, was presented, which might strengthen the current predictive systems. The biosensor construction procedure was extremely simple, economical, and time-saving, as it involved only the chemisorption step of the voltammetrically active receptor (tripeptide (Cys-Gly-Ile) labeled with methylene blue (MB) and the sealing thiol. The active form of MMP-1 was recognized based on its hydrolytic activity; as a consequence, the receptor fragment (-Ile-MB) was removed from the sensor surface. The biosensors constructed were characterized by a wide dynamic concentration response range (1.0 pg mL^-1-1.0 μg mL^-1) and a low detection limit (33 fg mL^-1), especially the biosensor with voltammetric detection, without the amplification step. One of the important advantages of the proposed biosensors is that they can be directly used to analyze the content of the active form of MMP-1 in clinical samples without the dilution step and any other preparation step.

Stabil idiyopatik pulmoner fibrozde hastalik şiddeti ve prognostik belirteçler ile matriks metallaproteinaz düzeyleri arasindaki ilişki

Purpose: Blood-derived biomarkers have been extensively considered as possible prognostic indicators in idiopathic pulmonary fibrosis (IPF) recently. In order to assess the value of circulating biomarkers in common IPF clinical practice, the study intends to draw conclusions regarding the link between disease severity, prognostic indicators, and serum matrix metalloproteinase in patients with stable idiopathic pulmonary fibrosis. Materials and Methods: The study comprised 22 people with an IPF diagnosis that had been verified by a multidisciplinary approach. The sociodemographic details, clinical and radiologic symptoms, pulmonary function tests and the Gender-Age-Physiology (GAP) score were noted. ELISA has been used to research serum MMP concentrations. Results: There is no statistically significant correlation between the Matrix Metalloproteinase (MMP) 2, MMP 7, MMP 9, and MMP13 and the GAP index and, pulmonary function tests, or disease severity. GAP score was found to be higher in stage 3 in patients with severe disease, in stage 2 in patients with moderate disease, and in stage 1 in patients with mild disease. Conclusion: There are consistent findings in the literature, despite the fact that the association between MMP and IPF prognostic markers, pulmonary function tests, and disease severity could not be seen in this investigation. However, because they could open the door to a cutting-edge treatment strategy, these indicators should be investigated prospectively in larger series.

Polycythemia is uncommon in dogs with chronic hypoxic pulmonary disease

Background

Prolonged tissue hypoxia caused by chronic pulmonary disease is commonly regarded as an important mechanism in the development of secondary polycythemia, but little clinical data are available to support this hypothesis.

Objective

To study the prevalence and severity of erythrocytosis accompanying chronic hypoxic pulmonary disease in dogs.

Animals

Forty‐seven dogs with hypoxic chronic pulmonary disease, 27 dogs with nonhypoxic chronic pulmonary disease, and 60 healthy controls.

Methods

Dogs with chronic pulmonary disease and chronic hypoxemia (partial pressure of arterial oxygen [PaO₂] < 80 mm Hg on at least 2 arterial blood gas measurements a minimum of 1 month apart) were identified retrospectively from patient records. Association between arterial oxygen and red blood cell parameters was analyzed using Pearson's correlation coefficients and multivariable linear regression analysis.

Results

Red blood cell parameters measured at the end of the hypoxemia period were within the laboratory reference range in most dogs. In chronically hypoxemic dogs, hematocrit (Hct) was increased in 4/47 (8.5%; 95% confidence interval [CI], 0‐17) dogs, erythrocyte count (Erytr) was increased in 12/47 (26%; 95%CI, 13‐38) dogs and hemoglobin concentration (Hb) was increased in 3/47 (6.4%; 95%CI, 0‐14) dogs. No marked polycythemia (Hct ≥65%) was noted in any of the dogs. Red blood cell parameters were not associated with the severity of hypoxemia (correlation to PaO₂: Erytr, r = −.14; Hb, r = −.21; Hct, r = −.14; P > .05 for all).

Conclusions and Clinical Importance

Polycythemia is uncommon, and usually mild if present, in dogs with chronic hypoxia caused by pulmonary disease.

Molecularly imprinted polymer-based extended-gate field-effect transistor (EG-FET) chemosensor for selective determination of matrix metalloproteinase-1 (MMP-1) protein

A conducting molecularly imprinted polymer (MIP) film was integrated with an extended-gate field-effect transistor (EG-FET) transducer to determine epitopes of matrix metalloproteinase-1 (MMP-1) protein biomarker of idiopathic pulmonary fibrosis (IPF) selectively. Most suitable epitopes for imprinting were selected with Basic Local Alignment Search Tool software. From a pool of MMP-1 epitopes, the two, i.e., MIAHDFPGIGHK and HGYPKDIYSS, the relatively short ones, most promising for MMP-1 determination, were selected, mainly considering their advantageous outermost location in the protein molecule and stability against aggregation. MIPs templated with selected epitopes of the MMP-1 protein were successfully prepared by potentiodynamic electropolymerization and simultaneously deposited as thin films on electrodes. The chemosensors, constructed of MIP films integrated with EG-FET, proved useful in determining these epitopes even in a medium as complex as a control serum. The limit of detection for the MIAHDFPGIGHK and HGYPKDIYSS epitope was ∼60 and 20 nM, respectively. Moreover, the chemosensors selectively recognized whole MMP-1 protein in the 50-500 nM concentration range in buffered control serum samples.

Matrix metalloproteinases inhibitors in idiopathic pulmonary fibrosis: Medicinal chemistry perspectives

Idiopathic pulmonary fibrosis (IPF) is a lethal disease with limited therapeutic options and a particularly poor prognosis. Matrix metalloproteinases (MMPs), promising targets for the treatment of IPF, have been identified as playing a pivotal role in IPF. Although the pathological processes of MMPs and IPF have been verified, there are no MMP inhibitors for the treatment of IPF in the clinic. In this review, we will present the latest developments in MMP inhibitors, including pharmacophores, binding modes, selectivity and optimization strategies. In addition, we will also discuss the future development direction of MMP inhibitors based on emerging tools and techniques.