BACKGROUND: Fibrosis of the connective tissue in the vaginal wall predominates in pelvic organ prolapse (POP), which is characterized by excessive fibroblast-to-myofibroblast differentiation and abnormal deposition of the extracellular matrix (ECM). Our study aimed to investigate the effect of ECM stiffness on vaginal fibroblasts and to explore the role of methyltransferase 3 (METTL3) in the development of POP. METHODS: Polyacrylamide hydrogels were applied to create an ECM microenvironment with variable stiffness to evaluate the effects of ECM stiffness on the proliferation, differentiation, and expression of ECM components in vaginal fibroblasts. METTL3 small interfering RNA and an overexpression vector were transfected into vaginal fibroblasts to evaluate the effects of METTL3 silencing and overexpression on matrix stiffness-induced vaginal fibroblast-to-myofibroblast differentiation and abnormal modulation of the ECM. Both procedures were detected by 5-ethynyl-2'-deoxyuridine (EdU) staining, Western blotting (WB), quantitative real-time polymerase chain reaction (RT-qPCR), and immunofluorescence (IF). RESULTS: Vaginal fibroblasts from POP patients exhibited increased proliferation ability, increased expression of α-smooth muscle actin (α-SMA), decreased expression of collagen I/III, and significantly decreased expression of tissue inhibitors of matrix metalloproteinases (TIMPs) in the stiff matrix ( P <0.05). Compared with those from non-POP patients, vaginal wall tissues from POP patients demonstrated a significant increase in METTL3 content ( P <0.05). However, silencing METTL3 expression in vaginal fibroblasts with high ECM stiffness resulted in decreased proliferation ability, decreased α-SMA expression, an increased ratio of collagen I/III, and increased TIMP1 and TIMP2 expression. Conversely, METTL3 overexpression significantly promoted the process of increased proliferation ability, increased α-SMA expression, decreased ratio of collagen I/III and decreased TIMP1 and TIMP2 expression in the soft matrix ( P <0.05). CONCLUSIONS Elevated ECM stiffness can promote excessive proliferation, differentiation, and abnormal ECM modulation, and the expression of METTL3 plays an important role in alleviating or aggravating matrix stiffness-induced vaginal fibroblast-to-myofibroblast differentiation and abnormal ECM modulation.
Humans ; Female ; Extracellular Matrix/metabolism* ; Cell Differentiation/genetics* ; Methyltransferases/metabolism* ; Pelvic Organ Prolapse/pathology* ; Fibroblasts/metabolism* ; Myofibroblasts/metabolism* ; Vagina/metabolism* ; Cell Proliferation/physiology* ; Cells, Cultured ; Middle Aged

OBJECTIVES: Osteoarthritis (OA) is one of the most common chronic degenerative diseases, with chondrocyte apoptosis and extracellular matrix (ECM) degradation as the major pathological changes. The mechanical stimulation can attenuate chondrocyte apoptosis and promote ECM synthesis, but the underlying molecular mechanisms remain unclear. This study aims to investigate the role of primary cilia (PC) in mediating the effects of mechanical stimulation on OA progression. METHODS: In vivo, conditional knockout mice lacking intraflagellar transport 88 (IFT88^flox/flox IFT88 knockout; i.e., primary cilia-deficient mice) were generated, with wild-type mice as controls. OA models were established via anterior cruciate ligament transection combined with destabilization of the medial meniscus, followed by treadmill exercise intervention. OA progression was evaluated by hematoxylin-eosin staining, safranin O-fast green staining, and immunohistochemistry; apoptosis was assessed by TUNEL staining; and limb function by rotarod testing. In vitro, primary articular chondrocytes were isolated from mice and transfected with lentiviral vectors to suppress IFT88 expression, thereby constructing a primary cilia-deficient cell model. Interleukin-1β (IL-1β) was used to induce an inflammatory environment, while cyclic tensile strain (CTS) was applied via a cell stretcher to mimic mechanical loading on chondrocytes. Immunofluorescence and Western blotting were used to detect the protein expression levels of type II collagen α1 chain (COL2A1), primary cilia, IFT88, and caspase-12; reverse transcription polymerase chain reaction was performed to assess COL2A1 mRNA levels; and flow cytometry was used to evaluate apoptosis. RESULTS: In vivo, treadmill exercise significantly reduced Osteoarthritis Research Society International (OARSI) scores and apoptotic cell rates, and improved balance ability in wild-type OA mice, whereas IFT88-deficient OA mice showed no significant improvement. In vitro, CTS inhibited IL-1β-induced ECM degradation and apoptosis in primary chondrocytes; however, this protective effect was abolished in cells with suppressed primary cilia expression. CONCLUSIONS Mechanical stimulation delays OA progression by mediating signal transduction through primary cilia, thereby inhibiting cartilage degeneration and chondrocyte apoptosis.
Animals ; Chondrocytes/cytology* ; Apoptosis/physiology* ; Mice ; Cilia/metabolism* ; Osteoarthritis/pathology* ; Extracellular Matrix/metabolism* ; Mice, Knockout ; Disease Progression ; Interleukin-1beta ; Male ; Cells, Cultured

Frostbite is the most common cold injury and is caused by both immediate cold-induced cell death and the gradual development of localized inflammation and tissue ischemia. Delayed healing of frostbite often leads to scar formation, which not only causes psychological distress but also tends to result in the development of secondary malignant tumors. Therefore, a rapid healing method for frostbite wounds is urgently needed. Herein, we used a mouse skin model of frostbite injury to evaluate the recovery process after frostbite. Moreover, single-cell transcriptomics was used to determine the patterns of changes in monocytes, macrophages, epidermal cells, and fibroblasts during frostbite. Most importantly, human-induced pluripotent stem cell (hiPSC)-derived skin organoids combined with gelatin-hydrogel were constructed for the treatment of frostbite. The results showed that skin organoid treatment significantly accelerated wound healing by reducing early inflammation after frostbite and increasing the proportions of epidermal stem cells. Moreover, in the later stage of wound healing, skin organoids reduced the overall proportions of fibroblasts, significantly reduced fibroblast-to-myofibroblast transition by regulating the integrin α5β1-FAK pathway, and remodeled the extracellular matrix (ECM) through degradation and reassembly mechanisms, facilitating the restoration of physiological ECM and reducing the abundance of ECM associated with abnormal scar formation. These results highlight the potential application of organoids for promoting the reversal of frostbite-related injury and the recovery of skin functions. This study provides a new therapeutic alternative for patients suffering from disfigurement and skin dysfunction caused by frostbite.
Animals ; Organoids/metabolism* ; Mice ; Humans ; Wound Healing ; Frostbite/metabolism* ; Skin/pathology* ; Induced Pluripotent Stem Cells/cytology* ; Cicatrix/pathology* ; Fibroblasts/metabolism* ; Disease Models, Animal ; Mice, Inbred C57BL ; Extracellular Matrix/metabolism* ; Male

Liver fibrosis is a dynamic wound-healing response characterized by the agglutination of the extracellular matrix (ECM). Si-Wu-Tang (SWT), a traditional Chinese medicine (TCM) formula, is known for treating gynecological diseases and liver fibrosis. Our previous studies demonstrated that long non-coding RNA H19 (H19) was markedly upregulated in fibrotic livers while its deficiency markedly reversed fibrogenesis. However, the mechanisms by which SWT influences H19 remain unclear. Thus, we established a bile duct ligation (BDL)-induced liver fibrosis model to evaluate the hepatoprotective effects of SWT on various cells in the liver. Our results showed that SWT markedly improved ECM deposition and bile duct reactions in the liver. Notably, SWT relieved liver fibrosis by regulating the transcription of genes involved in the cytoskeleton remodeling, primarily in hepatic stellate cells (HSCs), and influencing cytoskeleton-related angiogenesis and hepatocellular injury. This modulation collectively led to reduced ECM deposition. Through extensive bioinformatics analyses, we determined that H19 acted as a miRNA sponge and mainly inhibited miR-200, miR-211, and let7b, thereby regulating the above cellular regulatory pathways. Meanwhile, SWT reversed H19-related miRNAs and signaling pathways, diminishing ECM deposition and liver fibrosis. However, these protective effects of SWT were diminished with the overexpression of H19 in vivo. In conclusion, our study elucidates the underlying mechanisms of SWT from the perspective of H19-related signal networks and proposes a potential SWT-based therapeutic strategy for the treatment of liver fibrosis.
Humans ; RNA, Long Noncoding/genetics* ; Liver Cirrhosis/genetics* ; Liver/metabolism* ; Hepatic Stellate Cells/pathology* ; MicroRNAs/metabolism* ; Extracellular Matrix/metabolism* ; Drugs, Chinese Herbal

Integrin is a large family of cell adhesion molecules (CAMs) which involves in the interaction of cells/cells and cells/ extracellular matrix (ECM) to mediate cell proliferation, differentiation, adhesion, migration, etc. In recent years, aberrant expression of integrin has been clearly found in many tumor studies, indicating that integrin is closely related to tumor formation and development. Meanwhile, it has effects on tumor cell differentiation, cell migration, proliferation and tumor neovascularization. The study of drugs targeting integrins is of great significance for the clinical treatment of tumors. Because of its important role in tumorigenesis and development, integrin has become a promising target for the treatment of cancer. This review summarizes the role of integrin in tumor development and the current state of integrin inhibitors to provide a valuable reference for subsequent research.
Antineoplastic Agents ; pharmacology ; therapeutic use ; Biological Products ; pharmacology ; therapeutic use ; Cell Movement ; drug effects ; Cell Proliferation ; drug effects ; Extracellular Matrix ; metabolism ; Humans ; Integrins ; antagonists & inhibitors ; classification ; genetics ; metabolism ; Neoplasms ; drug therapy ; pathology ; Neovascularization, Pathologic ; drug therapy ; pathology ; Signal Transduction ; drug effects

OBJECTIVE: To explore the effect of telmisartan on the expression of metadherin in the kidney of mice with unilateral ureter obstruction. METHODS: Eighteen male C57 mice were randomized into sham-operated group, model group and telmisartan treatment group. In the latter two groups, renal interstitial fibrosis as the result of unilateral ureter obstruction (UUO) was induced by unilateral ureteral ligation with or without telmisartan intervention. Renal pathological changes of the mice were assessed using Masson staining, and immunohistochemistry and Western blotting were used to detect the expression of extracellular matrix proteins and metadherin in the kidney of the mice. In the experiment, cultured mouse renal tubular epithelial cells (mTECs) were stimulated with transforming growth factor-β1 (TGF-β1) and transfected with a siRNA targeting metadherin, and the changes in the expressions of extracellular matrix proteins and metadherin were detected using Western blotting. RESULTS: The expressions of extracellular matrix proteins and metadherin increased significantly in the kidney of mice with UUO ( < 0.05). Intervention with telmisartan significantly lowered the expressions of extracellular matrix proteins and metadherin and alleviated the pathology of renal fibrosis in mice with UUO ( < 0.05). In cultured mTECs, siRNA-mediated knockdown of metadherin obviously reversed TGF-β1-induced increase in the expressions of extracellular matrix proteins and metadherin. CONCLUSIONS Telmisartan can suppress the production of extracellular matrix proteins and the expression of metadhein to attenuate UUO-induced renal fibrosis in mice.
Angiotensin II Type 1 Receptor Blockers ; Animals ; Antihypertensive Agents ; Extracellular Matrix Proteins ; metabolism ; Fibrosis ; Kidney ; drug effects ; metabolism ; pathology ; Male ; Membrane Proteins ; genetics ; metabolism ; Mice ; Mice, Inbred C57BL ; RNA, Small Interfering ; Random Allocation ; Telmisartan ; pharmacology ; Transforming Growth Factor beta1 ; pharmacology ; Ureteral Obstruction ; complications ; metabolism

OBJECTIVE: To study whether tricalcium phosphate(TCP) wear particles cause injuries of periprosthetic osteocytes in the mouse calvaria, and to explain its molecular mechanism. METHODS: Thirty six-week(ICR)male mice were randomly divided into sham group, model (TCP) group and 3-methyladenine (3-MA) group. A murine calvarial model of osteolysis was established by 30 mg of TCP wear particles implantation over the periosteum around the middle suture of calvaria in mice. On the second postoperative day, the autophagy specific inhibitor 3-MA (1.0 mg/kg) was subcutaneously injected to the calvaria in the 3-MA-treated mice every other day. After 2 weeks, blood and the calvaria were obtained. Micro-CT was used to detect bone mineral density(BMD), bone volume fraction (BVF) and porosity number. HE staining and flow cytometry were performed to analyze the viability and apoptosis of periprosthetic osteocytes. The serum levels of dentin matrix protein 1(DMP-1) and sclerostin (SOST) were determined by ELISA. The proteins expressions of DMP-1, SOST, Beclin-1 and microtuble-associated protein 1 light chain 3 (LC-3) were detected by Western blot in the calvaria osteocytes. RESULTS: Compared with the sham group, the mice in the TCP group showed that a significant decrease in the viability of periprosthetic osteocytes, but obvious increases in number of osteocytes death and osteocytes apoptosis (<0.05), and in serum level and protein expression of SOST; significant decreases in serum level and protein expression of DMP-1 (<0.05), and remarkable up-regulation of autophagy-related factors beclin-1 and the conversion of LC3-Ⅱ from LC3-I in the calvaria osteocytes. Compared with TCP group, the mice in the 3-MA group showed that injuries of calvaria osteocytes were obviously aggravated, and osteocytes apoptosis was significantly increased (<0.05). CONCLUSIONS TCP wear particles can cause injuries of periprosthetic osteocytes via activation of apoptosis and autophagy, which promotes osteolysis around the prosthesis osteolysis and joint aseptic loosening.
Animals ; Apoptosis ; Beclin-1 ; metabolism ; Bone Density ; Calcium Phosphates ; adverse effects ; Extracellular Matrix Proteins ; metabolism ; Glycoproteins ; metabolism ; Male ; Mice ; Mice, Inbred ICR ; Microtubule-Associated Proteins ; metabolism ; Osteocytes ; pathology ; Osteolysis ; Prostheses and Implants ; adverse effects ; Skull

Articular cartilage is a connective tissue consisting of a specialized extracellular matrix (ECM) that dominates the bulk of its wet and dry weight. Type II collagen and aggrecan are the main ECM proteins in cartilage. However, little attention has been paid to less abundant molecular components, especially minor collagens, including type IV, VI, IX, X, XI, XII, XIII, and XIV, etc. Although accounting for only a small fraction of the mature matrix, these minor collagens not only play essential structural roles in the mechanical properties, organization, and shape of articular cartilage, but also fulfil specific biological functions. Genetic studies of these minor collagens have revealed that they are associated with multiple connective tissue diseases, especially degenerative joint disease. The progressive destruction of cartilage involves the degradation of matrix constituents including these minor collagens. The generation and release of fragmented molecules could generate novel biochemical markers with the capacity to monitor disease progression, facilitate drug development and add to the existing toolbox for in vitro studies, preclinical research and clinical trials.
Aggrecans ; chemistry ; genetics ; metabolism ; Animals ; Biomarkers ; metabolism ; Cartilage, Articular ; chemistry ; metabolism ; pathology ; Collagen ; chemistry ; classification ; genetics ; metabolism ; Extracellular Matrix Proteins ; chemistry ; genetics ; metabolism ; Gene Expression ; Humans ; Osteoarthritis ; diagnosis ; genetics ; metabolism ; pathology ; Protein Isoforms ; chemistry ; classification ; genetics ; metabolism

OBJECTIVEThe exact mechanisms of defect closure in patients with perimembranous ventricular septal defect (PMVSD) remain unknown. We hypothesized that the expression of urokinase type plasminogen activator (uPA) and plasminogen activator inhibitor-1 (PAI-1) may mediate extracellular matrix (ECM) remodeling in aneurysms.

METHODSeven normal heart tricuspid septal leaflet and 33 aneurysms were collected in Shanghai Renji Hospital and Shanghai Children's Medical Center from January 2008 to June 2010. Immunohistochemical expression of uPA and PAI-1 in 4 normal heart valvular tissues and 15 aneurysms was detected with immunohistochemical methods. The expression of uPA and PAI-1 mRNA in 3 normal heart valvular tissues and 7 aneurysms was studied by real time fluorescent PCR; the protein expression of uPA and PAI-1 in 4 normal heart valvular tissues and 11 aneurysms was tested with Western blotting.

RESULTThe surface of the aneurysms were completely covered by endothelial cells. Two types of granulation tissue, myxoid and fibrous, were associated with the aneurismal formation. uPA were recognized predominantly in valvar interstitial cells (VICs) which located mainly in regions adjacent to the endothelium and smooth muscle cells of blood vessels. PAI-1 was found in both VICs which located mainly in granulation tissue and endothelial cells. Nine aneurysms expressed a higher uPA activity than 4 normal valvular tissues ((74.6±11.8)% vs. (49.5±7.4)%; t = 3.87, P = 0.003) and six aneurysms expressed a low uPA activity ((10.3±3.1)% vs. (49.5±7.4)%; t=11.78, P=0.000) and a high PAI-1 activity ((55.2±1.7)% vs. (50.8±3.8)%; t=2.55, P=0.034) using immunohistochemical methods. uPA / PAI-1 ratio of protein expression tested by Western blot was 0.88±0.22 in four normal heart vavular tissues; five aneurysms expressed high uPA activity and low PAI-1 activity and uPA/PAI-1 ratio was 4.26±2.04; while the other 6 cases expressed low uPA activity and high PAI-1 activity and uPA/PAI-1 ratio was 0.30±0.07; the difference among the three groups was statistically significant (P<0.05). The rate of uPA/PAI-1 in relative copy of mRNA expression among normal heart valvular tissue, high uPA expressed aneurysms and low uPA expressed aneurysms are also significantly different (2.14±0.17 vs. 0.45±0.04; 2.14±0.17 vs. 4.38±1.41, P<0.05) respectively.

CONCLUSIONThe expression of uPA and PAI-1 in VICs suggests that interactions among these molecules contribute to the aneurysm formation and development. This provides a potential mechanism for defect closure in patients with PMVSD.

Aneurysm ; pathology ; Blotting, Western ; China ; Endothelial Cells ; cytology ; Extracellular Matrix ; metabolism ; Granulation Tissue ; pathology ; Heart Septal Defects, Ventricular ; pathology ; Humans ; Immunohistochemistry ; Plasminogen Activator Inhibitor 1 ; metabolism ; RNA, Messenger ; Urokinase-Type Plasminogen Activator ; metabolism

PURPOSE: The degradation of the extracellular matrix has been shown to play an important role in the treatment of hepatic cirrhosis. In this study, the effect of thalidomide on the degradation of extracellular matrix was evaluated in a rat model of hepatic cirrhosis. MATERIALS AND METHODS: Cirrhosis was induced in Wistar rats by intraperitoneal injection of carbon tetrachloride (CCl4) three times weekly for 8 weeks. Then CCl4 was discontinued and thalidomide (100 mg/kg) or its vehicle was administered daily by gavage for 6 weeks. Serum hyaluronic acid, laminin, procollagen type III, and collagen type IV were examined by using a radioimmunoassay. Matrix metalloproteinase-13 (MMP-13), tissue inhibitor of metalloproteinase-1 (TIMP-1), and alpha-smooth muscle actin (alpha-SMA) protein in the liver, transforming growth factor beta1 (TGF-beta1) protein in cytoplasm by using immunohistochemistry and Western blot analysis, and MMP-13, TIMP-1, and TGF-beta1 mRNA levels in the liver were studied using reverse transcriptase polymerase chain reaction. RESULTS: Liver histopathology was significantly better in rats given thalidomide than in the untreated model group. The levels of TIMP-1 and TGF-beta1 mRNA and protein expressions were decreased significantly and MMP-13 mRNA and protein in the liver were significantly elevated in the thalidomide-treated group. CONCLUSION: Thalidomide may exert its effects on the regulation of MMP-13 and TIMP-1 via inhibition of the TGF-beta1 signaling pathway, which enhances the degradation of extracellular matrix and accelerates the regression of hepatic cirrhosis in rats.
Actins ; Animals ; Carbon Tetrachloride/toxicity ; Collagen Type III/metabolism ; Down-Regulation ; Extracellular Matrix/metabolism ; Immunohistochemistry ; Immunosuppressive Agents/*pharmacology ; Liver Cirrhosis, Experimental/chemically induced/*metabolism/pathology/*prevention & control ; Male ; RNA, Messenger/analysis/metabolism ; Rats ; Rats, Wistar ; Thalidomide/*pharmacology ; Tissue Inhibitor of Metalloproteinase-1/biosynthesis/*drug effects ; Transcription Factor RelA/biosynthesis/drug effects ; Transforming Growth Factor beta1/biosynthesis/*drug effects ; Transforming Growth Factors/metabolism