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

The aims of the present study were to evaluate the effects of puerarin on angiotensin II-induced cardiac fibroblast proliferation and to explore the molecular mechanisms of action. Considering the role of HO in nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation, we hypothesized that modulating catalase activity would be a potential target in regulating the redox-sensitive pathways. Our results showed that the activation of Rac1 was dependent on the levels of intracellular HO. Puerarin blocked the phosphorylation of extracellular regulated protein kinases (ERK)1/2, abolished activator protein (AP)-1 binding activity, and eventually attenuated cardiac fibroblast proliferation through the inhibition of HO-dependent Rac1 activation. Further studies revealed that angiotensin II treatment resulted in decreased catalase protein expression and enzyme activity, which was disrupted by puerarin via the upregulation of catalase protein expression at the transcriptional level and the prolonged protein degradation. These findings indicated that the anti-proliferation mechanism of puerarin was mainly through blocking angiontensin II-triggered downregulation of catalase expression and HO-dependent Rac1 activation.
Angiotensin II ; pharmacology ; Angiotensin II Type 1 Receptor Blockers ; pharmacology ; Animals ; Animals, Newborn ; Catalase ; genetics ; metabolism ; Cell Proliferation ; drug effects ; Cells, Cultured ; Extracellular Signal-Regulated MAP Kinases ; antagonists & inhibitors ; metabolism ; Fibroblasts ; Gene Expression Regulation ; drug effects ; Heart ; drug effects ; Hydrogen Peroxide ; metabolism ; pharmacology ; Isoflavones ; pharmacology ; Mice ; Myocardium ; cytology ; enzymology ; metabolism ; NADPH Oxidases ; antagonists & inhibitors ; metabolism ; Neuropeptides ; metabolism ; Signal Transduction ; drug effects ; Transcription Factor AP-1 ; antagonists & inhibitors ; metabolism ; Transcriptional Activation ; drug effects ; rac1 GTP-Binding Protein ; metabolism

OBJECTIVETo observe the effect of electroacupuncture (EA) stimulation on the expressions of angiotensinogen (AGT), angiotensin II type 1 receptor (AT1R), endothelin-1 (ET1), and endothelin A receptor (ETAR) mRNA in spontaneously hypertensive rat (SHR) aorta.

METHODSEighteen male SHRs were randomly divided into three groups, an SHR group, an SHR Baihui (DU 20) and Zusanli (ST 36) acupoint (SHR-AP) group, and an SHR non-acupoint (SHR-NAP) group, with 6 rats in each group. Six Wistar rats were used as a control. Rats in the SHR-AP group were stimulated by DU 20 and ST 36 acupoints, both of which were connected with EA. EA was handled one time every Monday, Wednesday and Friday, for total 24 times (8 weeks). SHRNAP rats were acupointed at a 15°angle flat into 0.5 cm to two points, which were 1 and 2 cm from rail tip separately. EA parameters were the same as the SHR-AP rats. SHR control rats and Wistar rats were fixed without EA. Real-time quantitative polymerase chain reaction (PCR) was used to measure AGT, AT1R, ET1, and ETAR mRNA expression in rat aorta.

RESULTSEA stimulation significantly reduced rat aorta vascular AGT, ET1, ETAR and AT1R mRNA expressions in the SHR-AP and SHR-NAP groups (P <0.01). Among these four genes, AT1R mRNA expression was significantly lower in the SHR-AP than in the SHR-NAP group (P <0.01).

CONCLUSIONEA could reduce the AT1R mRNA expression in SHR-AP rat aorta, indicating a potential mechanism for the hypotensive effects of EA.

Angiotensinogen ; genetics ; metabolism ; Animals ; Aorta ; metabolism ; physiopathology ; Blood Pressure ; Electroacupuncture ; Endothelin-1 ; genetics ; metabolism ; Gene Expression Regulation ; Male ; RNA, Messenger ; genetics ; metabolism ; Rats, Inbred SHR ; Receptor, Angiotensin, Type 1 ; genetics ; metabolism ; Receptor, Endothelin A ; genetics ; metabolism

Endothelial dysfunction induced by intermittent hypoxia (IH) participates in obstructive sleep apnea syndrome (OSAS)-associated cardiovascular disorders. Myeloid differentiation primary response 88 (MyD88) and tumor necrosis factor receptor-associated factor 6 (TRAF6) regulate numerous downstream adaptors like mitogen-activated protein kinases (MAPKs) and the subsequent oxidative stress and inflammatory responses. This study aimed to characterize the role of MyD88/TRAF6 in IH-treated cell function and its associated signaling. Human umbilical vein endothelial cells (HUVECs) were randomly exposed to IH or normoxia for 0, 2, 4 and 6 h. Western blotting was used to detect the expression pattern of target gene proteins [angiotensin 1 receptor (AT1R), p-ERK1/2, p-p38MAPK, MyD88 and TRAF6], and the relationships among these target genes down-regulated by the corresponding inhibitors were studied. Finally, the influence of these target genes on proliferation of HUVECs was also assessed by EdU analysis. Protein levels of AT1R, TRAF6 and p-ERK1/2 were increased after IH exposure, with a slight rise in MyD88 and a dynamic change in p-p38MAPK. The down-regulation of TRAF6 by siRNA reduced ERK1/2 phosphorylation during IH without any effects on AT1R. Blockade of AT1R with valsartan decreased TRAF6 and p-ERK1/2 protein expression after IH exposure. ERK1/2 inhibition with PD98059 suppressed only AT1R expression. IH promoted HUVECs proliferation, which was significantly suppressed by the inhibition of TRAF6, AT1R and ERK1/2. The findings demonstrate that TRAF6 regulates the proliferation of HUVECs exposed to short-term IH by modulating cell signaling involving ERK1/2 downstream of AT1R. Targeting the AT1R-TRAF6-p-ERK1/2 signaling pathway might be helpful in restoring endothelial function.
Cell Hypoxia ; Cell Proliferation ; Cells, Cultured ; Gene Expression Regulation ; Human Umbilical Vein Endothelial Cells ; physiology ; Humans ; MAP Kinase Signaling System ; drug effects ; Phosphorylation ; Receptor, Angiotensin, Type 1 ; genetics ; metabolism ; TNF Receptor-Associated Factor 6 ; genetics ; metabolism ; Valsartan ; pharmacology

The purpose of this study was to identify the differences in angiogenesis gene expression between normal and diabetic keratocytes stimulated with interleukin-1alpha (IL-1alpha) and tumor necrosis factor-alpha (TNF-alpha). Primarily cultured normal and diabetic keratocytes were treated with 20 ng/mL of IL-1a and TNF-alpha for 6 hr. cDNA was hybridized to an oligonucleotide microarray. Microarray analysis was used to identify differentially expressed genes that were further evaluated by real-time polymerase chain reaction (RT-PCR). Diabetes keratocytes overexpressed vital components of angiogenesis including Agtr1, and under-expressed components related to the blood vessel maturation, including Dcn. Cytokine-treated diabetic keratocytes differentially expressed components of angiogenesis. OLETF keratocytes after treatment with IL-1alpha and TNF-alpha showed the newly expressed 15 and 14 genes, respectively. Newly and commonly under-expressed five genes followed by treatment with both IL-1alpha and TNF-alpha were also evident. RT-PCR showed results similar to the microarray results. Agtr1 and Itga1 showed an increased expression in diabetic keratocytes compared with normal corneal keratocytes, especially after TNF-alpha treatment. Il6 appeared strong expression after interleukin-1alpha treatment, but showed down expression after TNF-alpha treatment. Further studies to analyze and confirm the significance of the identified angiogenetic genes of diabetes are needed.
Animals ; Cells, Cultured ; Gene Expression Regulation/drug effects ; Interleukin-1alpha/pharmacology ; Keratinocytes/cytology/drug effects/*metabolism ; Neovascularization, Physiologic/*genetics ; *Oligonucleotide Array Sequence Analysis ; Rats ; Real-Time Polymerase Chain Reaction ; Receptor, Angiotensin, Type 1/genetics/metabolism ; Tumor Necrosis Factor-alpha/pharmacology

OBJECTIVETo observe the effects of Shenqi Compound (SQC) on the mRNA expression of angiotensin II type 1 receptor (AT1R) in the aorta of Goto-Kakizaki (GK) rats.

METHODSTotally 67 GK rats were randomly divided into 5 groups, i.e., the GK group (n =18), the model group (n =16), the atorvastatin group (n =17), and the SQC group (n =16). Another a normal control group was set up (n =18). The diabetic macrovascular disease model was prepared by adding L-NAME (at the daily dose of 0.10 mg/mL) in drinking water for GK rats. GK rats, except those in the normal control group were fed with high fat diet. Atorvastatin (at the daily dose of 1.60 mg/kg) and SQC (at the daily dose of 1.44 g/kg) were respectively administered by gastrogavage, once daily for 35 successive days. The blood glucose was determined by glucose oxidase method once per week. After 5-week medication, the contents of triglyceride (TG) and total cholesterol (TC) were determined by ELISA. The serum concentrations of angiotensin I (Ang II) were determined by RIA. The mRNA expression of AT1R in the aorta was determined by real-time quantitative reverse transcriptase PCR (RT-PCR).

RESULTSThe blood glucose level was obviously lower in both the atorvastatin group and the SQC group after 4 weeks of medication (P <0.05). Besides, it was significantly lower in the SQC group than in the model group by the end of the 4th week (P <0.05). The concentrations of TG, TC and serum Ang II , and the mRNA expression of AT1R in the aorta were significantly higher in the model group than in the normal control group (P <0.01). After 5-week medication, the concentrations of TG, TC and serum Ang I , and the mRNA expression of AT1 R in the aorta were significantly lower in the atorvastatin group and the SQC group than in the model group (P <0.01, P <0.05). The mRNA expression of AT1R was significantly higher in the SQC group than in the atorvastatin group (P <0.05).

CONCLUSIONSSQC could significantly reduce the levels of blood glucose, TG, TC, down-regulate the mRNA expression of AT1R in the aorta, and decrease the expressions of serum Ang II of GK rats with diabetic macrovascular disease. AT1 R might be one of effective targets of SQC in treating diabetic macrovascular diseases.

Angiotensin II ; blood ; Animals ; Aorta ; drug effects ; metabolism ; Blood Glucose ; analysis ; Cholesterol ; blood ; Diabetes Mellitus, Experimental ; drug therapy ; metabolism ; Diabetes Mellitus, Type 2 ; drug therapy ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Male ; RNA, Messenger ; genetics ; Rats ; Receptor, Angiotensin, Type 1 ; genetics ; metabolism ; Triglycerides ; blood

OBJECTIVETo study the effect of Songling Xuemaikang Capsule (SXC) on blood pressure of spontaneously hypertensive rats (SHR) and regulatory mechanisms for peroxisome proliferator activated receptor-gamma (PPARgamma).

METHODSTotally 24 10-week-old SHR rats were randomly divided into the blank control group, the Chinese medicine (CM) group, and the Western medicine (WM) group, 8 in each group. Rats in the CM group were administered with SXC at the daily dose of 20 mg/kg by gastrogavage. Those in the WM group were administered with ramipril at the daily dose of 1 mg/kg by gastrogavage. Those in the blank control group were administered with equal volume of normal saline. The blood pressure was measured once per week. The cardiac ultrasound was performed 4 weeks later. Rats were killed and then blood was sampled from abdominal aorta. mRNA expressions of liver PPARgamma and angiotensin II type 1 receptor (AT1R) were detected by fluorescence real-time quantitative PCR. Protein expressions of PPARgamma and AT1R were detected using immunohistochemical assay (SP). The contents of PPARgamma and AT1R were quantitatively analyzed by Western blot.

RESULTSAfter 4 weeks of treatment, the blood pressure decreased in the CM group, showing statistical difference when compared with the blank control group (P < 0.01). CM was inferior to WM in lowering blood pressure. But as a whole, CM was more stable and could maintain blood pressure at a relatively stable level. The cardiac ejection fraction increased in the CM group, showing statistical difference when compared with the blank control group (P < 0.05, P < 0.01). The mRNA and protein expressions of liver PPARgamma were up-regulated in the CM group, showing statistical difference when compared with the blank control group (P < 0.05, P < 0.01). CM could obviously inhibit the AT1R mRNA expression, and down-regulate the protein expression of AT1R, showing statistical difference when compared with the blank control group and the WM group respectively (P < 0.01).

CONCLUSIONSXC decreased blood pressure and improved the cardiac ejection fraction, which might be partially achieved by up-regulating the PPARgamma mRNA expression and protein synthesis, and inhibiting the AT1R mRNA expression and AT1R protein synthesis.

Animals ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Hypertension ; drug therapy ; metabolism ; physiopathology ; Male ; PPAR gamma ; metabolism ; RNA, Messenger ; genetics ; Rats ; Rats, Inbred SHR ; Receptor, Angiotensin, Type 1 ; metabolism

OBJECTIVETo analyze the expression of angiotensin II (ANG II) receptor and apoptosis in myocardium in rats of endotoxemia.

METHODSModel of endotoxemia was induced by intraperitoneal injection with lipopolysaccharide (LPS) 10 mg/kg in male Wistar rats and saline was injected into control group. The rats were killed at 2 h or 6 h after saline (control) or LPS . Expression of the correlation factors related to apoptosis of Bcl-2, Bax, AT1 and AT2 receptor in myocardial tissue were detected with immunohistochemistry (IHC), and changes of myocardial cells apoptosis was detected by the method of TUNEL. The gene expression of AT1 and AT2 receptor was examined by RT-PCR. The pathological changes of myocardial tissue were observed by electron microscope.

RESULTSCompared with control group , the expression of AT1 and AT2 receptor were significantly decreased, especially in 6 h group; and the expression of Bcl-2 and Bax were decreased, the ratio of Bcl-2/Bax had the downtrend as well as the apoptosis of myocardial cells.

CONCLUSIONInterfered by LPS, the down regulation of AT1 and AT2 receptor expression has the negative relation with apoptosis of myocardial cells, this result indicated that down regulation of AT1 and AT2 receptor expression maybe related to cardiac functional impairment, which maybe help us to find a new protective path to prevent myocardial damage induced by systemic inflammatory.

Animals ; Apoptosis ; Endotoxemia ; metabolism ; Male ; Myocytes, Cardiac ; cytology ; metabolism ; RNA, Messenger ; genetics ; Rats ; Rats, Wistar ; Receptor, Angiotensin, Type 1 ; metabolism ; Receptor, Angiotensin, Type 2 ; metabolism

The present study was designed to test the hypothesis that a medium-term simulated microgravity can induce region-specific remodeling in large elastic arteries with their innermost smooth muscle (SM) layers being most profoundly affected. The second purpose was to examine whether these changes can be prevented by a simulated intermittent artificial gravity (IAG). The third purpose was to elucidate whether vascular local renin-angiotensin system (L-RAS) plays an important role in the regional vascular remodeling and its prevention by the gravity-based countermeasure. This study consisted of two interconnected series of in-vivo and ex-vivo experiments. In the in-vivo experiments, the tail-suspended, hindlimb unloaded rat model was used to simulate microgravity-induced cardiovascular deconditioning for 28 days (SUS group); and during the simulation period, another group was subjected to daily 1-hour dorso-ventral (-G(x)) gravitation provided by restoring to normal standing posture (S + D group). The activity of vascular L-RAS was evaluated by examining the gene and protein expression of angiotensinogen (Ao) and angiotensin II receptor type 1 (AT1R) in the arterial wall tissue. The results showed that SUS induced an increase in the media thickness of the common carotid artery due to hypertrophy of the four SM layers and a decrease in the total cross-sectional area of the nine SM layers of the abdominal aorta without significant change in its media thickness. And for both arteries, the most prominent changes were in the innermost SM layers. Immunohistochemistry and in situ hybridization revealed that SUS induced an up- and down-regulation of Ao and AT1R expression in the vessel wall of common carotid artery and abdominal aorta, respectively, which was further confirmed by Western blot analysis and real time PCR analysis. Daily 1-hour restoring to normal standing posture over 28 days fully prevented these remodeling and L-RAS changes in the large elastic arteries that might occur due to SUS alone. In the ex-vivo experiments, to elucidate the important role of transmural pressure in vascular regional remodeling and differential regulation of L-RAS activity, we established an organ culture system in which rat common carotid artery, held at in-vivo length, can be perfused and pressurized at varied flow and pressure for 7 days. In arteries perfused at a flow rate of 7.9 mL/min and pressurized at 150 mmHg, but not at 0 or 80 mmHg, for 3 days led to an augmentation of c-fibronectin (c-FN) expression, which was also more markedly expressed in the innermost SM layers, and an increase in Ang II production detected in the perfusion fluid. However, the enhanced c-FN expression and increased Ang II production that might occur due to a sustained high perfusion pressure alone were fully prevented by daily restoration to 0 or 80 mmHg for a short duration. These findings from in-vivo and ex-vivo experiments have provided evidence supporting our hypothesis that redistribution of transmural pressures might be the primary factor that initiates region-specific remodeling of arteries during microgravity and the mechanism of IAG is associated with an intermittent restoration of the transmural pressures to their normal distribution. And they also provide support to the hypothesis that L-RAS plays an important role in vascular adaptation to microgravity and its prevention by the IAG countermeasure.
Angiotensinogen ; genetics ; metabolism ; Animals ; Aorta, Abdominal ; pathology ; physiopathology ; Carotid Artery, Common ; pathology ; physiopathology ; Hindlimb Suspension ; Male ; Muscle, Smooth, Vascular ; metabolism ; pathology ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptor, Angiotensin, Type 1 ; genetics ; metabolism ; Renin-Angiotensin System ; physiology ; Weightlessness Simulation

OBJECTIVETo elucidate the effect of valsartan on human glomerular mesangial cells oxidative stress and the expression of the receptor for advanced glycation end products (RAGE) induced by the advanced glycation end-products (AGEs).

METHODSHuman glomerular mesangial cells were treated with advanced glycation end-product-bovine serum albumin (AGE-BSA) in the presence of valsartan. The reactive oxygen species (ROS) in cells were measured by Flow cytometry, and the mRNA of p47 phox, which was the primary subunits of NADPH oxidase, was detected by semi-quantitative reberse transcription polymerase chain reaction (RT-PCR). The mRNA of RAGE was detected by RT-PCR and the RAGE protein was assayed by immunocytochemistry.

RESULTSThe product of ROS, and the expression of p47 phox and RAGE in mesangial cells, which were treated with AGE-BSA in the presence of valsartan, were down-regulated compared with the groups treated with AGE-BSA (P < 0.05). Valsartan dose-dependently and time-dependently inhibited the AGE-elicited overexpression of RAGE, ROS and p47(phox) in mesangial cells.

CONCLUSIONValsartan could inhibit RAGE expression through downregulation of oxidative stress.

Angiotensin II Type 1 Receptor Blockers ; pharmacology ; Antioxidants ; pharmacology ; Glycation End Products, Advanced ; pharmacology ; Humans ; Mesangial Cells ; cytology ; metabolism ; Oxidative Stress ; drug effects ; RNA, Messenger ; genetics ; metabolism ; Receptor for Advanced Glycation End Products ; Receptors, Immunologic ; genetics ; metabolism ; Serum Albumin, Bovine ; pharmacology ; Tetrazoles ; pharmacology ; Valine ; analogs & derivatives ; pharmacology ; Valsartan