-
Folia Morphologica 2019The objective of this study was to investigate whether long term formaldehyde inhalation may affect periodontal membrane and alveolar bone loss leading to periodontitis....
BACKGROUND
The objective of this study was to investigate whether long term formaldehyde inhalation may affect periodontal membrane and alveolar bone loss leading to periodontitis. The negative effects of formaldehyde were described using vascular endothelial growth factor (VEGF), matrix metallopeptidase 2 (MMP-2) and osteonectin antibodies involved in the extracellular matrix and angiogenetic development.
MATERIALS AND METHODS
Thirty adult Wistar albino rats were used in this study. Rats were divided into two groups: a control group (n = 15) and formaldehyde administered group (n = 15). Formaldehyde group was exposed to inhalation of 10 ppm formaldehyde 8 hours a day, 5 days a week for 5 weeks. Maxillary bone regions were dissected under anaesthesia. After fixation in 10% formaldehyde solution, tissues were passed through graded ethanol series to obtain paraffin blocks. Five-micrometre histological sections were cut with RM2265 rotary microtome stained with Masson trichrome and VEGF, MMP-2 and osteonectin antibodies for examination under Olympus BH-2 light microscopy.
RESULTS
The present study revealed that congestion in blood vessels, degeneration of collagen fibres and alveolar matrix around alveolar bone were observed to be more significant in formaldehyde group than the control group (p ≤ 0.001). Interestingly, VEGF expression in the formaldehyde group was the most significant finding between the two groups (p < 0.001). When compared inflammation, MMP-2 and osteonectin expressions were significant (p < 0.01) in the formaldehyde group.
CONCLUSIONS
It was suggested that formaldehyde toxicity decreased the expression of MMP-2 and in osteoblasts as well as affecting the retention of MMP levels in tooth cavity, which is very low in collagen fibres. But, vice versa for the expression of VEGF in dilated vascular endothelial cells and osteocytes in alveolar bone. As a conclusion, formaldehyde disrupts the periodontal membrane and may cause collagen fibres degeneration by affecting the alveolar bone matrix.
Topics: Alveolar Process; Animals; Antibodies; Formaldehyde; Matrix Metalloproteinase 2; Osteonectin; Periodontium; Rats, Wistar; Vascular Endothelial Growth Factor A
PubMed: 30536359
DOI: 10.5603/FM.a2018.0110 -
International Journal of Molecular... Jul 2023The matricellular secreted protein acidic and rich in cysteine (SPARC; also known as osteonectin), is involved in the regulation of extracellular matrix (ECM) synthesis,...
The matricellular secreted protein acidic and rich in cysteine (SPARC; also known as osteonectin), is involved in the regulation of extracellular matrix (ECM) synthesis, cell-ECM interactions, and bone mineralization. We found decreased SPARC expression in aged skin. Incubating foreskin fibroblasts with recombinant human SPARC led to increased type I collagen production and decreased matrix metalloproteinase-1 (MMP-1) secretion at the protein and mRNA levels. In a three-dimensional culture of foreskin fibroblasts mimicking the dermis, SPARC significantly increased the synthesis of type I collagen and decreased its degradation. In addition, SPARC also induced receptor-regulated SMAD (R-SMAD) phosphorylation. An inhibitor of transforming growth factor-beta (TGF-β) receptor type 1 reversed the SPARC-induced increase in type I collagen and decrease in MMP-1, and decreased SPARC-induced R-SMAD phosphorylation. Transcriptome analysis revealed that SPARC modulated expression of genes involved in ECM synthesis and regulation in fibroblasts. RT-qPCR confirmed that a subset of differentially expressed genes is induced by SPARC. These results indicated that SPARC enhanced ECM integrity by activating the TGF-β signaling pathway in fibroblasts. We inferred that the decline in SPARC expression in aged skin contributes to process of skin aging by negatively affecting ECM integrity in fibroblasts.
Topics: Humans; Aged; Osteonectin; Collagen Type I; Matrix Metalloproteinase 1; Cells, Cultured; Extracellular Matrix; Transforming Growth Factor beta; Signal Transduction; Fibroblasts
PubMed: 37569556
DOI: 10.3390/ijms241512179 -
Frontiers in Endocrinology 2022Diabetic retinopathy (DR) is one of the most severe microvascular complications of diabetes mellitus (DM). Secreted protein acidic and rich in cysteine (SPARC) has been...
BACKGROUNDS
Diabetic retinopathy (DR) is one of the most severe microvascular complications of diabetes mellitus (DM). Secreted protein acidic and rich in cysteine (SPARC) has been found to play an important role in many diseases, but its role and mechanism in DR remain unknown.
METHODS
We studied the role of SPARC and integrin β1 in vascular pathophysiology and identified potential therapeutic translation. The SPARC levels were tested in human serum and vitreous by ELISA assay, and then the Gene Expression Omnibus (GEO) dataset was used to understand the key role of the target gene in DR. In human retinal capillary endothelial cells (HRCECs), we analyzed the mRNA and protein level by RT-PCR, immunohistochemistry, and Western blotting. The cell apoptosis, cell viability, and angiogenesis were analyzed by flow cytometry, CCK-8, and tube formation.
RESULTS
In this study, we investigated the role of SPARC in the development and progression of human DR and high glucose-induced HRCEC cells and found that the SPARC-ITGB1 signaling pathway mimics early molecular and advanced neurovascular pathophysiology complications of DR. The result revealed that DR patients have a high-level SPARC expression in serum and vitreous. Knockdown of SPARC could decrease the expressions of inflammatory factors and VEGFR, inhibit cell apoptosis and angiogenesis, and increase cell viability by regulating integrin β1 in HRCECs.
CONCLUSION
SPARC promotes diabetic retinopathy the regulation of integrin β1. The results of this study can provide a potential therapeutic application for the treatment of DR.
Topics: Cysteine; Diabetes Mellitus; Diabetic Retinopathy; Endothelial Cells; Humans; Integrin beta1; Neovascularization, Pathologic; Osteonectin; Proteins
PubMed: 35721704
DOI: 10.3389/fendo.2022.869519 -
Exercise Immunology Review 2020An increasing body of evidence suggests that age-related immune changes and chronic inflammation contribute to cancer development. Recognizing that exercise has... (Review)
Review
An increasing body of evidence suggests that age-related immune changes and chronic inflammation contribute to cancer development. Recognizing that exercise has protective effects against cancer, promotes immune function, and beneficially modulates inflammation with ageing, this review outlines the current evidence indicating an emerging role for exercise immunology in preventing and treating cancer in older adults. A specific focus is on data suggesting that muscle- derived cytokines (myokines) mediate anti-cancer effects through promoting immunosurveillance against tumourigenesis or inhibiting cancer cell viability. Previous studies suggested that the exercise-induced release of myokines and other endocrine factors into the blood increases the capacity of blood serum to inhibit cancer cell growth in vitro. However, little is known about whether this effect is influenced by ageing. Prostate cancer is the second most common cancer in men. We therefore examined the effects of serum collected before and after exercise from healthy young and older men on the metabolic activity of androgen-responsive LNCaP and androgen-unresponsive PC3 prostate cancer cells. Exercise-conditioned serum collected from the young group did not alter cell metabolic activity, whereas post-exercise serum (compared with pre-exercise serum) from the older men inhibited the metabolic activity of LNCaP cancer cells. Serum levels of candidate cancer-inhibitory myokines oncostatin M and osteonectin increased in both age groups following exercise. Serum testosterone increased only in the younger men postexercise, potentially attenuating inhibitory effects of myokines on the LNCaP cell viability. The data from our study and the evidence in this review suggest that mobilizing serum factors and immune cells may be a key mechanism of how exercise counteracts cancer in the older population.
Topics: Aged; Aging; Cell Line, Tumor; Exercise; Humans; Immune System; Male; Oncostatin M; Osteonectin; Prostatic Neoplasms
PubMed: 32139350
DOI: No ID Found -
The Journal of Biological Chemistry Dec 1994Osteonectin is an adhesive glycoprotein synthesized constitutively by osteoblasts, endothelial cells, and megakaryocytes. Bone-derived and platelet-derived osteonectins... (Comparative Study)
Comparative Study
Osteonectin is an adhesive glycoprotein synthesized constitutively by osteoblasts, endothelial cells, and megakaryocytes. Bone-derived and platelet-derived osteonectins differ in their electrophoretic mobility and carbohydrate content, and each displays different affinities for collagen matrices. Both types of osteonectin bind to plasminogen (Kd(app), of 4.7 +/- 1.0 x 10(-8) M for bone osteonectin and 1.2 +/- 0.1 x 10(-7) M for platelet osteonectin). The osteonectin-plasminogen interaction is inhibited by alpha 2-antiplasmin and epsilon-aminocaproic acid, suggesting that the interaction is mediated through the kringle 1 region of plasminogen. Both osteonectins enhance the rate of plasmin generation by tissue-type plasminogen activator to approximately the same extent as fibrinogen. Equilibrium binding measurements conducted using total internal reflection fluorescence spectroscopy indicate that plasminogen binds to collagen in the presence of bone osteonectin (Kd = 1.30 +/- 0.1 x 10(-7) M). No binding of plasminogen to collagen matrix was detected in the presence of platelet osteonectin or in the absence of bone osteonectin. Bone osteonectin-dependent binding of plasminogen to collagen matrix is reversed by the addition of epsilon-aminocaproic acid. The ability of both types of osteonectin to bind to and influence plasminogen activation and of bone osteonectin to anchor plasminogen on collagen matrices suggests that osteonectin may play a role in directing extracellular matrix proteolysis.
Topics: Aminocaproic Acid; Binding, Competitive; Blood Platelets; Bone and Bones; Collagen; Enzyme-Linked Immunosorbent Assay; Humans; Kinetics; Osteonectin; Plasminogen; Protein Binding; Spectrometry, Fluorescence; Structure-Activity Relationship; Tissue Plasminogen Activator; alpha-2-Antiplasmin
PubMed: 7982919
DOI: No ID Found -
Annals of Surgery Aug 2005We sought to examine the expression and functional role of osteonectin in primary and metastatic pancreatic ductal adenocarcinoma (PDAC).
OBJECTIVE
We sought to examine the expression and functional role of osteonectin in primary and metastatic pancreatic ductal adenocarcinoma (PDAC).
BACKGROUND
The glycoprotein osteonectin plays a vital role in cell-matrix interactions and is involved in various biologic processes. Overexpression of osteonectin is present in malignant tumors and correlates with disease progression and poor prognosis.
METHODS
Expression of osteonectin was analyzed by quantitative polymerase chain reaction and immunohistochemistry in pancreatic tissues and by enzyme-linked immunosorbent assay in the serum of patients and donors. Recombinant osteonectin and specific antisense oligonucleotides were used to examine the effects of osteonectin on induction of target genes, and on proliferation and invasiveness of pancreatic cancer cells.
RESULTS
There was a 31-fold increase in osteonectin mRNA levels in PDAC and a 16-fold increase in chronic pancreatitis as compared with the normal pancreas (P < 0.01). By immunohistochemistry, faint immunoreactivity was detected in the normal pancreas. In contrast, strong staining of the cancer cells was observed in addition to extensive osteonectin immunoreactivity in surrounding fibroblasts and in the extracellular matrix. In metastatic tissues, strong immunoreactivity was observed in fibroblasts and in extracellular matrix surrounding metastatic cancer cells, whereas the signal was absent in most tumor cells. In vitro studies showed that osteonectin was able to inhibit cancer cell growth while promoting invasiveness of pancreatic tumor cells.
CONCLUSION
Osteonectin is markedly overexpressed in pancreatic cancer and has the potential to increase the invasiveness of pancreatic cancer cells.
Topics: Adenocarcinoma; Adult; Aged; Disease Progression; Enzyme-Linked Immunosorbent Assay; Extracellular Matrix; Female; Fibroblasts; Humans; Immunohistochemistry; Male; Middle Aged; Neoplasm Invasiveness; Oligonucleotides, Antisense; Osteonectin; Pancreatic Neoplasms; Pancreatitis; Polymerase Chain Reaction; Prognosis; RNA, Messenger; Recombinant Proteins; Tumor Cells, Cultured
PubMed: 16041213
DOI: 10.1097/01.sla.0000171866.45848.68 -
Journal of Musculoskeletal & Neuronal... 2006This report summarizes the evidence that the control of the concentration of free calcium ions in body fluids is centered at mineralized bone surfaces. This process... (Review)
Review
This report summarizes the evidence that the control of the concentration of free calcium ions in body fluids is centered at mineralized bone surfaces. This process involves an increase in the solubility of bone mineral produced by the non-collagenous proteins existing in the bone extracellular fluid (ECF) and on the adjacent surfaces of bone. The result is a basic equilibrium level produced in the absence of parathyroid hormone (PTH), which is well above the solubility of bone mineral. The effect of PTH is to increase the solubility of bone mineral still further, but the mechanism by which the hormone acts is unknown. The lining cells of the bone contain receptors for PTH and can be observed to respond to this hormone, but the relationship between this response and the increased solubility of bone remains to be discovered. Further research in this field is strongly urged.
Topics: Animals; Bone and Bones; Calcification, Physiologic; Calcium; Durapatite; Extracellular Fluid; Homeostasis; Humans; Osteonectin; Parathyroid Hormone
PubMed: 17185838
DOI: No ID Found -
Matrix Biology : Journal of the... Jun 2012There is considerable interest in understanding prostate cancer metastasis to bone and the interaction of these cells with the bone microenvironment....
There is considerable interest in understanding prostate cancer metastasis to bone and the interaction of these cells with the bone microenvironment. Osteonectin/SPARC/BM-40 is a collagen binding matricellular protein that is enriched in bone. Its expression is increased in prostate cancer metastases, and it stimulates the migration of prostate carcinoma cells. However, the presence of osteonectin in cancer cells and the stroma may limit prostate tumor development and progression. To determine how bone matrix osteonectin affects the behavior of prostate cancer cells, we modeled prostate cancer cell-bone interactions using the human prostate cancer cell line PC-3, and mineralized matrices synthesized by wild type and osteonectin-null osteoblasts in vitro. We developed this in vitro system because the structural complexity of collagen matrices in vivo is not mimicked by reconstituted collagen scaffolds or by more complex substrates, like basement membrane extracts. Second harmonic generation imaging demonstrated that the wild type matrices had thick collagen fibers organized into longitudinal bundles, whereas osteonectin-null matrices had thinner fibers in random networks. Importantly, a mouse model of prostate cancer metastases to bone showed a collagen fiber phenotype similar to the wild type matrix synthesized in vitro. When PC-3 cells were grown on the wild type matrices, they displayed decreased cell proliferation, increased cell spreading, and decreased resistance to radiation-induced cell death, compared to cells grown on osteonectin-null matrix. Our data support the idea that osteonectin can suppress prostate cancer pathogenesis, expanding this concept to the microenvironment of skeletal metastases.
Topics: Animals; Blotting, Western; Bone Matrix; Cell Communication; Cell Death; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cell Shape; Cell Survival; Gamma Rays; Male; Mice; Osteoblasts; Osteonectin; Prostatic Neoplasms; Recombinant Proteins; Tumor Microenvironment
PubMed: 22525512
DOI: 10.1016/j.matbio.2012.03.002 -
Folia Morphologica 2020This study presents the evaluation of the damage in the bone tissue resulting from a calvarial defect in rats and the efficiency of exposure to an ozone application with...
BACKGROUND
This study presents the evaluation of the damage in the bone tissue resulting from a calvarial defect in rats and the efficiency of exposure to an ozone application with an alloplastic bone graft on the calvarial bone damage.
MATERIALS AND METHODS
Wistar male rats (n = 56) were divided into four groups: a control group (n = 14), defect and ozone group (n = 14), defect and graft group (n = 14), and defect, graft, and ozone group (n = 14). Under anaesthesia, a circular full-thickness bone defect was created in all groups, and the experimental groups were further divided into two sub-groups, with 7 rats in each group sacrificed at the end of the 4th and 8th weeks. Bone samples were dissected, fixed in 10% formalin solution, and decalcified with 5% ethylene-diamine-tetraacetic acid (EDTA). After the routine follow-up on tissues, immunostaining of osteopontin and osteonectin antibodies was applied to sections and observed under a light microscope.
RESULTS
The control group exhibited osteopontin and osteonectin expression in fibroblasts and inflammatory cells at the end of the 4th week with an acceleration at the 8th week. Ozone administration elucidated new trabecular bone formation by increasing osteoblastic activity. Lastly, our observations underscore that a combination of allograft and ozone application increased the osteoblast, osteocyte, and bone matrix development at the 4th and 8th weeks.
CONCLUSIONS
Exposure to an ozone application with an alloplastic bone graft on calvarial bone damage may induce osteoblastic activity, matrix development, mature bone cell formation, and new bone formation in rats.
Topics: Animals; Bone Transplantation; Immunohistochemistry; Male; Osteonectin; Osteopontin; Ozone; Rats, Wistar; Skull
PubMed: 31489606
DOI: 10.5603/FM.a2019.0101 -
Investigative Ophthalmology & Visual... Dec 2022Secreted protein acidic and rich in cysteine (SPARC) is a matricellular glycoprotein abundantly expressed in basement membranes and capsules surrounding a variety of...
PURPOSE
Secreted protein acidic and rich in cysteine (SPARC) is a matricellular glycoprotein abundantly expressed in basement membranes and capsules surrounding a variety of organs and tissues. It mediates extracellular matrix organization and has been implicated in cell contraction. Here, we evaluated the expression of SPARC in the murine lacrimal gland at adulthood and during inflammation.
METHODS
Lacrimal glands of young mice (4-6 weeks old) and adult mice (32-40 weeks old) were used for extraction of DNA, RNA, and protein. The presence of SPARC was assessed by quantitative PCR, ELISA, and immunofluorescence microscopy. 5-Methylcytosine and DNA methylation were evaluated using ELISA and bisulfite genomic sequencing, respectively. The effects of cytokines and inflammation in Sparc expression were evaluated in vitro and in the non-obese diabetic (NOD) mouse model of Sjögren's syndrome.
RESULTS
The mRNA and protein levels of SPARC were downregulated in lacrimal glands of mature adult mice presenting age-related histological alterations such as increased deposition of lipofuscin and lipids. Epigenetic analyses indicated that glands in adult mice contain higher levels of global DNA methylation and show increased hypermethylation of specific CpG sites within the Sparc gene promoter. Analysis of smooth muscle actin (SMA)-green fluorescent protein (GFP) transgenic mice revealed that SPARC localizes primarily to myoepithelial cells within the gland. Treatment of myoepithelial cells with IL-1β or TNF-α and the development of inflammation in the NOD mice led to decreased transcription of Sparc.
CONCLUSIONS
SPARC is a novel matricellular glycoprotein expressed by myoepithelial cells in the lacrimal gland. Loss of SPARC during adulthood and chronic inflammation might have detrimental consequences on myoepithelial cell contraction and the secretion of tear fluid.
Topics: Animals; Mice; Lacrimal Apparatus; Mice, Inbred NOD; Microscopy, Fluorescence; Osteonectin; Inflammation; Age Factors
PubMed: 36479944
DOI: 10.1167/iovs.63.13.8