Objective: To explore the pathogenic mechanism of the miR-340/high mobility group box 1 (HMGB1) axis in the formation of liver fibrosis. Methods: A rat liver fibrosis model was established by injecting CCl(4) intraperitoneally. miRNAs targeting and validating HMGB1 were selected with gene microarrays after screening the differentially expressed miRNAs in rats with normal and hepatic fibrosis. The effect of miRNA expressional changes on HMGB1 levels was detected by qPCR. Dual luciferase gene reporter assays (LUC) was used to verify the targeting relationship between miR-340 and HMGB1. The proliferative activity of the hepatic stellate cell line HSC-T6 was detected by thiazolyl blue tetrazolium bromide (MTT) assay after co-transfection of miRNA mimics and HMGB1 overexpression vector, and the expression of extracellular matrix (ECM) proteins type I collagen and α-smooth muscle actin (SMA) was detected by western blot. Statistical analysis was performed by analysis of variance and the LSD-t test. Results: Hematoxylin-eosin and Masson staining results showed that the rat model of liver fibrosis was successfully established. Gene microarray analysis and bioinformatics prediction had detected eight miRNAs possibly targeting HMGB1, and animal model validation had detected miR-340. qPCR detection results showed that miR-340 had inhibited the expression of HMGB1, and a luciferase complementation assay suggested that miR-340 had targeted HMGB1. Functional experiments results showed that HMGB1 overexpression had enhanced cell proliferation activity and the expression of type I collagen and α-SMA, while miR-340 mimics had not only inhibited cell proliferation activity and the expression of HMGB1, type I collagen, and α-SMA, but also partially reversed the promoting effect of HMGB1 on cell proliferation and ECM synthesis. Conclusion: miR-340 targets HMGB1 to inhibit the proliferation and ECM deposition in hepatic stellate cells and plays a protective role during the process of liver fibrosis.
Animals ; Rats ; Cell Proliferation ; Collagen Type I/metabolism* ; Fibrosis ; Hepatic Stellate Cells ; HMGB1 Protein/genetics* ; Liver Cirrhosis/pathology* ; MicroRNAs/metabolism*

The present study was aimed to investigate the role and mechanism of glutaminolysis of cardiac fibroblasts (CFs) in hypertension-induced myocardial fibrosis. C57BL/6J mice were administered with a chronic infusion of angiotensin II (Ang II, 1.6 mg/kg per d) with a micro-osmotic pump to induce myocardial fibrosis. Masson staining was used to evaluate myocardial fibrosis. The mice were intraperitoneally injected with BPTES (12.5 mg/kg), a glutaminase 1 (GLS1)-specific inhibitor, to inhibit glutaminolysis simultaneously. Immunohistochemistry and Western blot were used to detect protein expression levels of GLS1, Collagen I and Collagen III in cardiac tissue. Neonatal Sprague-Dawley (SD) rat CFs were treated with 4 mmol/L glutamine (Gln) or BPTES (5 μmol/L) with or without Ang II (0.4 μmol/L) stimulation. The CFs were also treated with 2 mmol/L α-ketoglutarate (α-KG) under the stimulation of Ang II and BPTES. Wound healing test and CCK-8 were used to detect CFs migration and proliferation respectively. RT-qPCR and Western blot were used to detect mRNA and protein expression levels of GLS1, Collagen I and Collagen III. The results showed that blood pressure, heart weight and myocardial fibrosis were increased in Ang II-treated mice, and GLS1 expression in cardiac tissue was also significantly up-regulated. Gln significantly promoted the proliferation, migration, mRNA and protein expression of GLS1, Collagen I and Collagen III in the CFs with or without Ang II stimulation, whereas BPTES significantly decreased the above indices in the CFs. α-KG supplementation reversed the inhibitory effect of BPTES on the CFs under Ang II stimulation. Furthermore, in vivo intraperitoneal injection of BPTES alleviated cardiac fibrosis of Ang II-treated mice. In conclusion, glutaminolysis plays an important role in the process of cardiac fibrosis induced by Ang II. Targeted inhibition of glutaminolysis may be a new strategy for the treatment of myocardial fibrosis.
Rats ; Mice ; Animals ; Rats, Sprague-Dawley ; Angiotensin II/pharmacology* ; Fibroblasts ; Mice, Inbred C57BL ; Fibrosis ; Collagen/pharmacology* ; Collagen Type I/metabolism* ; RNA, Messenger/metabolism* ; Myocardium/pathology*

Humans ; Matrix Metalloproteinase 9 ; Collagen Type I ; Pelvic Organ Prolapse/metabolism*

OBJECTIVE: To investigate whether the Runx2 gene can induce the differentiation of human amniotic mesenchymal stem cells (hAMSCs) to ligament fibroblasts <i>in vitroi> and promote the tendon-bone healing in rabbits. METHODS: hAMSCs were isolated from the placentas voluntarily donated from healthy parturients and passaged, and then identified by flow cytometric identification. Adenoviral vectors carrying Runx2 gene (Ad-Runx2) and empty vector adenovirus (Ad-NC) were constructed and viral titer assay; then, the 3rd generation hAMSCs were transfected with Ad-Runx2 (Ad-Runx2 group) or Ad-NC (Ad-NC group). The real-time fluorescence quantitative PCR and Western blot were used to detect Runx2 gene and protein expression to verify the effectiveness of Ad-Runx2 transfection of hAMSCs; and at 3 and 7 days after transfection, real-time fluorescence quantitative PCR was further used to detect the expressions of ligament fibroblast-related genes [vascular endothelial growth factor (VEGF), collagen type Ⅰ, Fibronectin, and Tenascin-C]. The hAMSCs were used as a blank control group. The hAMSCs, hAMSCs transfected with Ad-NC, and hAMSCs were mixed with Matrigel according to the ratio of 1 : 1 and 1 : 2 to construct the cell-scaffold compound. Cell proliferation was detected by cell counting kit 8 (CCK-8) assay, and the corresponding cell-scaffold compound with better proliferation were taken for subsequent animal experiments. Twelve New Zealand white rabbits were randomly divided into 4 groups of sham operation group (Sham group), anterior cruciate ligament reconstruction group (ACLR group), anterior cruciate ligament reconstruction+hAMSCs transfected with Ad-NC-scaffold compound group (Ad-NC group), and anterior cruciate ligament reconstruction+hAMSCs transfected with Ad-Runx2-scaffold compound group (Ad-Runx2 group), with 3 rabbits in each group. After preparing the ACL reconstruction model, the Ad-NC group and the Ad-Runx2 group injected the optimal hAMSCs-Matrigel compunds into the bone channel correspondingly. The samples were taken for gross, histological (HE staining and sirius red staining), and immunofluorescence staining observation at 1 month after operation to evaluate the inflammatory cell infiltration as well as collagen and Tenascin-C content in the ligament tissues. RESULTS: Flow cytometric identification of the isolated cells conformed to the phenotypic characteristics of MSCs. The Runx2 gene was successfully transfected into hAMSCs. Compared with the Ad-NC group, the relative expressions of VEGF and collagen type Ⅰ genes in the Ad-Runx2 group significantly increased at 3 and 7 days after transfection ( <i>Pi><0.05), Fibronectin significantly increased at 3 days ( <i>Pi><0.05), and Tenascin-C significantly increased at 3 days and decreased at 7 days ( <i>Pi><0.05). CCK-8 detection showed that there was no significant difference ( <i>Pi>>0.05) in the cell proliferation between groups and between different time points after mixed culture of two ratios. So the cell-scaffold compound constructed in the ratio of 1∶1 was selected for subsequent experiments. Animal experiments showed that at 1 month after operation, the continuity of the grafted tendon was complete in all groups; HE staining showed that the tissue repair in the Ad-Runx2 group was better and there were fewer inflammatory cells when compared with the ACLR group and the Ad-NC group; sirius red staining and immunofluorescence staining showed that the Ad-Runx2 group had more collagen typeⅠ and Ⅲ fibers, tending to form a normal ACL structure. However, the fluorescence intensity of Tenascin-C protein was weakening when compared to the ACLR and Ad-NC groups. CONCLUSION Runx2 gene transfection of hAMSCs induces directed differentiation to ligament fibroblasts and promotes tendon-bone healing in reconstructed anterior cruciate ligament in rabbits.
Pregnancy ; Female ; Humans ; Rabbits ; Animals ; Vascular Endothelial Growth Factor A/metabolism* ; Fibronectins/metabolism* ; Collagen Type I/genetics* ; Tenascin/metabolism* ; Collagen/metabolism* ; Anterior Cruciate Ligament/surgery* ; Mesenchymal Stem Cells ; Tendons/metabolism* ; Fibroblasts/metabolism*

Objective: JWH133, a cannabinoid type 2 receptor agonist, was tested for its ability to protect mice from bleomycin-induced pulmonary fibrosis. Methods: By using a random number generator, 24 C57BL/6J male mice were randomly divided into the control group, model group, JWH133 intervention group, and JWH133+a cannabinoid type-2 receptor antagonist (AM630) inhibitor group, with 6 mice in each group. A mouse pulmonary fibrosis model was established by tracheal instillation of bleomycin (5 mg/kg). Starting from the first day after modeling, the control group mice were intraperitoneally injected with 0.1 ml of 0.9% sodium chloride solution, and the model group mice were intraperitoneally injected with 0.1 ml of 0.9% sodium chloride solution. The JWH133 intervention group mice were intraperitoneally injected with 0.1 ml of JWH133 (2.5 mg/kg, dissolved in physiological saline), and the JWH133+AM630 antagonistic group mice were intraperitoneally injected with 0.1 ml of JWH133 (2.5 mg/kg) and AM630 (2.5 mg/kg). After 28 days, all mice were killed; the lung tissue was obtained, pathological changes were observed, and alveolar inflammation scores and Ashcroft scores were calculated. The content of type Ⅰ collagen in the lung tissue of the four groups of mice was measured using immunohistochemistry. The levels of interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) in the serum of the four groups of mice were measured using enzyme-linked immunosorbent assay (ELISA), and the content of hydroxyproline (HYP) in the lung tissue of the four groups of mice was measured. Western blotting was used to measure the protein expression levels of type Ⅲ collagen, α-smooth muscle actin (α-SMA), extracellular signal regulated kinase (ERK1/2), phosphorylated P-ERK1/2 (P-ERK1/2), and phosphorylated ribosome S6 kinase type 1 (P-p90RSK) in the lung tissue of mice in the four groups. Real-time quantitative polymerase chain reaction was used to measure the expression levels of collagen Ⅰ, collagen Ⅲ, and α-SMA mRNA in the lung tissue of the four groups of mice. Results: Compared with the control group, the pathological changes in the lung tissue of the model group mice worsened, with an increase in alveolar inflammation score (3.833±0.408 vs. 0.833±0.408, <i>Pi><0.05), an increase in Ashcroft score (7.333±0.516 vs. 2.000±0.633, <i>Pi><0.05), an increase in type Ⅰ collagen absorbance value (0.065±0.008 vs. 0.018±0.006, <i>Pi><0.05), an increase in inflammatory cell infiltration, and an increase in hydroxyproline levels [(1.551±0.051) μg/mg vs. (0.974±0.060) μg/mg, <i>Pi><0.05]. Compared with the model group, the JWH133 intervention group showed reduced pathological changes in lung tissue, decreased alveolar inflammation score (1.833±0.408, <i>Pi><0.05), decreased Ashcroft score (4.167±0.753, <i>Pi><0.05), decreased type Ⅰ collagen absorbance value (0.032±0.004, <i>Pi><0.05), reduced inflammatory cell infiltration, and decreased hydroxyproline levels [(1.148±0.055) μg/mg, <i>Pi><0.05]. Compared with the JWH133 intervention group, the JWH133+AM630 antagonistic group showed more severe pathological changes in the lung tissue of mice, increased alveolar inflammation score and Ashcroft score, increased type Ⅰ collagen absorbance value, increased inflammatory cell infiltration, and increased hydroxyproline levels. Compared with the control group, the expression of α-SMA, type Ⅲ collagen, P-ERK1/2, and P-p90RSK proteins in the lung tissue of the model group mice increased, while the expression of type Ⅰ collagen, type Ⅲ collagen, and α-SMA mRNA increased. Compared with the model group, the protein expression of α-SMA (relative expression 0.60±0.17 vs. 1.34±0.19, <i>Pi><0.05), type Ⅲ collagen (relative expression 0.52±0.09 vs. 1.35±0.14, <i>Pi><0.05), P-ERK1/2 (relative expression 0.32±0.11 vs. 1.14±0.14, <i>Pi><0.05), and P-p90RSK (relative expression 0.43±0.14 vs. 1.15±0.07, <i>Pi><0.05) decreased in the JWH133 intervention group. The type Ⅰ collagen mRNA (2.190±0.362 vs. 5.078±0.792, <i>Pi><0.05), type Ⅲ collagen mRNA (1.750±0.290 vs. 4.935±0.456, <i>Pi><0.05), and α-SMA mRNA (1.588±0.060 vs. 5.192±0.506, <i>Pi><0.05) decreased. Compared with the JWH133 intervention group, the JWH133+AM630 antagonistic group increased the expression of α-SMA, type Ⅲ collagen, P-ERK1/2, and P-p90RSK protein in the lung tissue of mice, and increased the expression of type Ⅲ collagen and α-SMA mRNA. Conclusion: In mice with bleomycin-induced pulmonary fibrosis, the cannabinoid type-2 receptor agonist JWH133 inhibited inflammation and improved extracellular matrix deposition, which alleviated lung fibrosis. The underlying mechanism of action may be related to the activation of the ERK1/2-RSK1 signaling pathway.
Mice ; Male ; Animals ; Pulmonary Fibrosis/pathology* ; Cannabinoid Receptor Agonists/metabolism* ; Collagen Type I/pharmacology* ; Collagen Type III/pharmacology* ; Hydroxyproline/pharmacology* ; Sodium Chloride/metabolism* ; Mice, Inbred C57BL ; Lung/pathology* ; Cannabinoids/adverse effects* ; Bleomycin/metabolism* ; Collagen/metabolism* ; Inflammation/pathology* ; RNA, Messenger/metabolism*

OBJECTIVE: To observe the effect of amygdalin on liver fibrosis in a liver fibrosis mouse model, and the underlying mechanisms were partly dissected in vivo and in vitro. METHODS: Thirty-two male mice were randomly divided into 4 groups, including control, model, low- and high-dose amygdalin-treated groups, 8 mice in each group. Except the control group, mice in the other groups were injected intraperitoneally with 10% carbon tetrachloride (CCl₄)-olive oil solution 3 times a week for 6 weeks to induce liver fibrosis. At the first 3 weeks, amygdalin (1.35 and 2.7 mg/kg body weight) were administered by gavage once a day. Mice in the control group received equal quantities of subcutaneous olive oil and intragastric water from the fourth week. At the end of 6 weeks, liver tissue samples were harvested to detect the content of hydroxyproline (Hyp). Hematoxylin and eosin and Sirius red staining were used to observe the inflammation and fibrosis of liver tissue. The expressions of collagen I (Col-I), alpha-smooth muscle actin (α-SMA), CD31 and transforming growth factor β (TGF-β)/Smad signaling pathway were observed by immunohistochemistry, quantitative real-time polymerase chain reaction and Western blot, respectively. The activation models of hepatic stellate cells, JS-1 and LX-2 cells induced by TGF-β1 were used in vitro with or without different concentrations of amygdalin (0.1, 1, 10 µmol/L). LSECs. The effect of different concentrations of amygdalin on the expressions of liver sinusoidal endothelial cells (LSECs) dedifferentiation markers CD31 and CD44 were observed. RESULTS: High-dose of amygdalin significantly reduced the Hyp content and percentage of collagen positive area, and decreased the mRNA and protein expressions of Col-I, α-SMA, CD31 and p-Smad2/3 in liver tissues of mice compared to the model group (P<0.01). Amygdalin down-regulated the expressions of Col-I and α-SMA in JS-1 and LX-2 cells, and TGFβ R1, TGFβ R2 and p-Smad2/3 in LX-2 cells compared to the model group (P<0.05 or P<0.01). Moreover, 1 and 10 µmol/L amygdalin inhibited the mRNA and protein expressions of CD31 in LSECs and increased CD44 expression compared to the model group (P<0.05 or P<0.01). CONCLUSIONS Amygdalin can dramatically alleviate liver fibrosis induced by CCl₄ in mice and inhibit TGF-β/Smad signaling pathway, consequently suppressing HSCs activation and LSECs dedifferentiation to improve angiogenesis.
Rats ; Male ; Mice ; Animals ; Transforming Growth Factor beta/metabolism* ; Amygdalin/therapeutic use* ; Endothelial Cells/metabolism* ; Olive Oil/therapeutic use* ; Rats, Wistar ; Smad Proteins/metabolism* ; Liver Cirrhosis/metabolism* ; Liver ; Transforming Growth Factor beta1/metabolism* ; Signal Transduction ; Collagen Type I/metabolism* ; Carbon Tetrachloride ; Hepatic Stellate Cells

OBJECTIVE: To investigate the protective mechanisms of Chinese medicine Shexiang Tongxin Dropping Pills (STDP) on heart failure (HF). METHODS: Isoproterenol (ISO)-induced HF rat model and angiotensin II (Ang II)-induced neonatal rat cardiac fibroblast (CFs) model were used in the present study. HF rats were treated with and without STDP (3 g/kg). RNA-seq was performed to identify differentially expressed genes (DEGs). Cardiac function was evaluated by echocardiography. Hematoxylin and eosin and Masson's stainings were taken to assess cardiac fibrosis. The levels of collagen I (Col I) and collagen III (Col III) were detected by immunohistochemical staining. CCK8 kit and transwell assay were implemented to test the CFs' proliferative and migratory activity, respectively. The protein expressions of α-smooth muscle actin (α-SMA), matrix metalloproteinase-2 (MMP-2), MMP-9, Col I, and Col III were detected by Western blotting. RESULTS: The results of RNA-seq analysis showed that STDP exerted its pharmacological effects on HF via multiple signaling pathways, such as the extracellular matrix (ECM)-receptor interaction, cell cycle, and B cell receptor interaction. Results from in vivo experiments demonstrated that STDP treatment reversed declines in cardiac function, inhibiting myocardial fibrosis, and reversing increases in Col I and Col III expression levels in the hearts of HF rats. Moreover, STDP (6, 9 mg/mL) inhibited the proliferation and migration of CFs exposed to Ang II in vitro (P<0.05). The activation of collagen synthesis and myofibroblast generation were markedly suppressed by STDP, also the synthesis of MMP-2 and MMP-9, as well as ECM components Col I, Col III, and α-SMA were decreased in Ang II-induced neonatal rats' CFs. CONCLUSIONS STDP had anti-fibrotic effects in HF, which might be caused by the modulation of ECM-receptor interaction pathways. Through the management of cardiac fibrosis, STDP may be a compelling candidate for improving prognosis of HF.
Rats ; Animals ; Matrix Metalloproteinase 2/metabolism* ; Matrix Metalloproteinase 9/metabolism* ; RNA-Seq ; Transcriptome/genetics* ; Heart Failure/drug therapy* ; Collagen ; Collagen Type I/metabolism* ; Fibrosis ; Myocardium/pathology*

OBJECTIVE: To establish a visual reporting system for evaluating the activity of collagen Ⅰ α 1 chain (<i>COL1A1i>) gene promoter in immortalized human hepatic stellate cells, so as to estimate the activation status of the cells and provide a new cell model for the screening and study of anti-hepatic fibrosis drugs. METHODS: The promoter sequence of human <i>COL1A1i> was amplified from the genomic DNA of human hepatocarcinoma cell line HepG2. Based on the pLVX-AcGFP1-N1 plasmid, the recombinant plasmid pLVX-COL1A1-enhanced green fluorescent protein (EGFP) was constructed, in which the enhanced green fluorescent protein gene expression was regulated by the <i>COL1A1i> promoter. The monoclonal cell line was acquired by stably transfecting pLVX-COL1A1-EGFP into the immortalized human hepatic stellate cell line LX-2 by the lentivirus packaging system and screening. The cell line was treated with transforming growth factor-β1 (TGF-β1) or co-treated with TGF-β1 and drugs with potential anti-hepatic fibrosis effects. The EGFP fluorescence intensity in cells was analyzed by the fluorescence microscope and ImageJ 1.49 software using a semi-quantitative method. The <i>COL1A1i> and <i>EGFPi> mRNA were detected by reverse transcription real-time quantitative PCR (RT-qPCR), and corresponding proteins were detected by Western blot. RESULTS: The recombinant plasmid pLVX-COL1A1-EGFP with the expression of <i>EGFPi> regulated by <i>COL1A1i> promoter was successfully constructed. Kozak sequence was added to enhance the expression of <i>EGFPi>, which was identified by double digestion and sequencing. The LX-2 monoclonal cell line LX-2-CE stably transfected with pLVX-COL1A1-EGFP was obtained. After co-treatment with TGF-β1 and 5 μmol/L dihydrotanshinone Ⅰ with potential anti-hepatic fibrosis effect for 24 h, the total fluorescence intensity and the average fluorescence intensity of LX-2-CE were lower than those in TGF-β1 single treatment group (<i>Pi> < 0.05), the intracellular mRNA and protein levels of <i>COL1A1i> and <i>EGFPi> were also lower than those in the TGF-β1 single treatment group (<i>Pi> < 0.05). CONCLUSION A reporter system for estimating activation of hepatic stellate cells based on <i>COL1A1i> promoter regulated <i>EGFPi> expression is successfully constructed, which could visually report the changes in <i>COL1A1i> expression, one of the activation-related markers of hepatic stellate cells, <i>in vitroi>. It provides a new cell model for the screening and study of anti-hepatic fibrosis drugs.
Humans ; Transforming Growth Factor beta1/pharmacology* ; Hepatic Stellate Cells/pathology* ; Liver Cirrhosis/genetics* ; Collagen Type I/pharmacology* ; RNA, Messenger/metabolism*

The purpose of this study was to investigate the effect of Geniposide on hepatic fibrosis and activation of hepatic stellate cells (HSCs) and to explore possible underlying mechanism. Human HSCs (LX-2) were treated with 5 ng/mL transforming growth factor-β1 (TGF-β1), followed by co-culture with Geniposide at various concentrations (0, 1, 2.5, 5, 10, 20, 40, 60, 80, 100 μmol/L). Cell viability was determined by MTT assay. Then, LX-2 cells were divided into control, TGF-β1 (5 ng/mL) and TGF-β1 + Geniposide (20 μmol/L) groups, and the gene and protein expression of collagen I, fibronectin, α-smooth muscle actin (α-SMA), p-Smad2 and p-Smad3 was detected by qPCR and Western blot, respectively. BALB/c mice were treated with CCl₄ (25%, 1 mL/kg) to generate a model of hepatic fibrosis (CCl₄ group), and the control group and CCl₄ + Geniposide group were administered with olive oil and CCl₄ + 40 mg/kg Geniposide, respectively. After 4 weeks of treatment, the liver function and serum hepatic fibrosis indexes of mice were detected, histological observation was performed by HE and Masson staining, and α-SMA expression in the tissue was analyzed by immunohistochemistry. Western blot was utilized for the determination of the protein expression of α-SMA, TGF-β1, p-Smad2 and p-Smad3. The results showed that Geniposide inhibited LX-2 cell proliferation. In addition, Geniposide significantly downregulated the gene and protein expression of collagen I, fibronectin and α-SMA and the expression of TGF-β1/Smad signaling-related proteins induced by TGF-β1 in vitro. Histological observations showed that Geniposide significantly inhibited CCl₄-induced hepatic fibrosis, HSC activation and expression of TGF-β1/Smad signaling-related proteins in mice. In summary, Geniposide prevents the hepatic fibrosis and HSC activation possibly through the inhibition of the TGF-β1/Smad signaling pathway.
Animals ; Collagen Type I/metabolism* ; Fibronectins ; Hepatic Stellate Cells/pathology* ; Iridoids ; Liver Cirrhosis/pathology* ; Mice ; Signal Transduction ; Smad Proteins/pharmacology* ; Transforming Growth Factor beta1/metabolism*

Objective To explore the effect of overwork (OW) on extracellular matrix of arterial vessel wall in rats. Methods Random number grouping method was employed to assign 18 Sprague-Dawley rats into three groups(<i>ni>=6):the control group(no special treatment),group OW(forced swimming twice a day for 15 days),and sleep deficiency(SD)+OW group(in addition to forced swimming twice a day,the rats were put on the platforms in water to limit sleep for 15 days).On the 16th day,the abdominal aorta and common carotid artery were collected after blood sampling from heart under deep anesthesia.A part of the abdominal aorta sample was taken for Masson staining of collagen fiber,and Verhoeff-Van Gieson staining was carried out for the elastic fiber of common carotid artery.Image J was employed for the quantitative analysis of collagen fiber and elastic fiber content.The expression of collagen 1(Col-1) protein was quantified by immunohistochemistry and the ultrastructure of vascular matrix was examined by transmission electron microscopy.The other part of the abdominal aorta sample was used to determine the mRNA levels of matrix metalloproteinase(MMP)-1,MMP-2,MMP-9,tissue inhibitor of metalloproteinases-1(TIMP-1),and Col-1 by quantitative real-time polymerase chain reaction. Results Compared with that in control group,the content of collagen fiber in groups OW and SD+OW had no significant change(all <i>Pi>>0.05);the content of elastic fiber in groups OW and SD+OW decreased(all <i>Pi><0.001) and had no significant difference between each other(<i>Pi>>0.05).The vascular vessel wall of group OW showed slight fiber breakage,while that of group SD+OW presented wormhole-like or spongy fiber fragmentation.The mRNA levels of MMP-1 and MMP-2 in groups OW and SD+OW had no significant difference between each other(<i>Pi>>0.05) but were higher than that in control group(all <i>Pi><0.001).The mRNA levels of MMP-9 and TIMP-1 had no significant difference among the three groups(all <i>Pi>>0.05).Groups OW and SD+OW had lower mRNA level(all <i>Pi><0.001) and protein level(all <i>Pi><0.001) of Col-1 than control group,while the mRNA and protein levels of Col-1 had no significant difference between groups OW and SD+OW(<i>Pi>>0.05). Conclusion OW can reduce the content of Col-1 and elastic fibers in the extracellular matrix of arterial vessels,destroy the elastic lamina of vascular wall,up-regulate the expression of MMP-1 and MMP-2,thereby injuring arterial vessels.
Animals ; Collagen Type I ; Extracellular Matrix/metabolism* ; Matrix Metalloproteinase 1/metabolism* ; Matrix Metalloproteinase 2/metabolism* ; Matrix Metalloproteinase 9/metabolism* ; RNA, Messenger/genetics* ; Rats ; Rats, Sprague-Dawley ; Tissue Inhibitor of Metalloproteinase-1/metabolism*