1
|
Qiang L, Li X, Li Q, Bo H, Liu Y, Lv M, Chen X, Ju H, Sang X, Li Z, Jin S. ABHD2 deficiency aggravates ovalbumin-induced airway remodeling through the PI3K/Akt pathway in an animal model of chronic asthma. Pol J Vet Sci 2023; 26:635-646. [PMID: 38088307 DOI: 10.24425/pjvs.2023.148283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Abstract
Airway remodeling is a major pathological characteristic of chronic obstructive pulmonary disease (COPD). This study aimed to investigate the effect of Abhd2 deficiency on ovalbumin (OVA)-induced airway remodeling and inflammation in vivo. Abhd2-deficient mice were used to establish an OVA-induced asthma model. Lung tissues were analyzed using hematoxylin and eosin (HE) staining, Masson staining, immunohistochemistry, quantitative reverse transcription- polymerase chain reaction (qRT-PCR), and western blotting were used to determine the role of Abhd2 in the regulation of OVA-induced airway remodeling and inflammation. Our findings revealed that the RNA expression of inflammatory factors, including IL-1β, IL-6, IL-4, and IL-13, was significantly increased in OVA-induced Abhd2 Gt/Gt asthmatic mice. The expression of IFN-γ was decreased significantly in OVA-induced Abhd2 Gt/Gt asthmatic mice. The protein expression of airway remodeling factors, including α-SMA, type I collagen, and Ki67, was also increased in OVA-induced Abhd2 Gt/Gt asthmatic mice compared to that in OVA-induced wild-type (WT) mice. Additionally, Abhd2 deficiency promoted the expression of p-Akt in tissues of the asthma model. These results suggest that Abhd2 deficiency exacerbates airway remodeling and inflammation through the PI3K/Akt pathway in chronic asthma.
Collapse
Affiliation(s)
- L Qiang
- Department of Respiratory Medicine, Fourth Affiliated Hospital, Harbin Medical University, 37# Yiyuan Street, Harbin 150001, Heilongjiang, China
| | - X Li
- Department of Respiratory Medicine, Fourth Affiliated Hospital, Harbin Medical University, 37# Yiyuan Street, Harbin 150001, Heilongjiang, China
| | - Q Li
- Department of pulmonary diseases, Heilongjiang Academy of Traditional Chinese Medicine, 33# Xidazhi Street, Harbin 150036, Heilongjiang, China
| | - H Bo
- Department of Intensive Care Unit, Fourth Affiliated Hospital, Harbin Medical University, 37# Yiyuan Street, Harbin 150001, Heilongjiang, China
| | - Y Liu
- Department of Respiratory Medicine, Fourth Affiliated Hospital, Harbin Medical University, 37# Yiyuan Street, Harbin 150001, Heilongjiang, China
| | - M Lv
- Department of Respiratory Medicine, Fourth Affiliated Hospital, Harbin Medical University, 37# Yiyuan Street, Harbin 150001, Heilongjiang, China
| | - X Chen
- Department of Respiratory Medicine, Fourth Affiliated Hospital, Harbin Medical University, 37# Yiyuan Street, Harbin 150001, Heilongjiang, China
| | - H Ju
- Department of Respiratory Medicine, Fourth Affiliated Hospital, Harbin Medical University, 37# Yiyuan Street, Harbin 150001, Heilongjiang, China
| | - X Sang
- Department of Respiratory Medicine, Fourth Affiliated Hospital, Harbin Medical University, 37# Yiyuan Street, Harbin 150001, Heilongjiang, China
| | - Z Li
- University of Tokyo, 3-8-1# Bunkyo ku, Tokyo 1130033, Tokyo, Japan
| | - S Jin
- Department of Respiratory Medicine, Fourth Affiliated Hospital, Harbin Medical University, 37# Yiyuan Street, Harbin 150001, Heilongjiang, China
| |
Collapse
|
2
|
Ding Q, Liu Y, Ju H, Song H, Xiao Y, Liu X, Ren G, Wei D. Reactive cutaneous capillary endothelial proliferation predicted the efficacy of camrelizumab in patients with recurrent/metastatic head and neck squamous cell carcinoma. Med Oral Patol Oral Cir Bucal 2023; 28:e525-e529. [PMID: 37330963 PMCID: PMC10635619 DOI: 10.4317/medoral.25919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 05/08/2023] [Indexed: 06/20/2023] Open
Abstract
BACKGROUND Reactive cutaneous capillary endothelial proliferation (RCCEP), a special adverse event (AE) only observed in patients treated with camrelizumab, was reported to be correlated with the efficacy of camrelizumab in patients with advanced hepatocellular carcinoma. This study to analyze the possible correlation between the occurrence of RCCEP and efficacy of camrelizumab in patients with recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC). MATERIAL AND METHODS In this study, we retrospectively analyzed the efficacy and RCCEP occurrence of camrelizumab in 58 patients with R/M HNSCC in the Shanghai Ninth People's Hospital affiliated to Shanghai JiaoTong University School of Medicine between January 2019 and June 2022. Kaplan-Meier analysis was used to assess the correlation between the occurrence of RCCEP and the survival of enrolled patients, and COX multifactor analysis was adopted to evaluate associated factors that affected the efficacy of camrelizumab immunotherapy. RESULTS A significant correlation between the incidence of RCCEP and a higher objective response rate was observed in this study (p=0.008). The occurrence of RCCEP was associated with better median overall survival (17.0 months vs. 8.7 months, p<0.0001, HR=5.944, 95% CI:2.097-16.84) and better median progression-free survival (15.1 months vs. 4.0 months, p<0.0001, HR=4.329,95% CI:1.683-11.13). In COX multifactor analysis, RCCEP occurrence was also an independent prognostic factor affecting OS and PFS in patients with R/M HNSCC. CONCLUSIONS The occurrence of RCCEP can show a better prognosis, it could be used as a clinical biomarker to predict the efficacy of camrelizumab treatment.
Collapse
Affiliation(s)
- Q Ding
- Department of Oral and Maxillofacial Surgery Ninth People's Hospital Shanghai Jiao Tong University School of Medicine Zip code: 200011, 639 Zhi-zao-ju Road, Shanghai, China
| | | | | | | | | | | | | | | |
Collapse
|
3
|
Kwon S, Lee E, Ju H, Ahn HJ, Lee SR, Choi EK, Suh J, Oh S, Rhee W. Machine Learning Prediction for the Recurrence After Electrical Cardioversion of Patients With Persistent Atrial Fibrillation. Korean Circ J 2023; 53:677-689. [PMID: 37653713 PMCID: PMC10625851 DOI: 10.4070/kcj.2023.0012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 05/25/2023] [Accepted: 06/13/2023] [Indexed: 09/02/2023] Open
Abstract
BACKGROUND AND OBJECTIVES There is limited evidence regarding machine-learning prediction for the recurrence of atrial fibrillation (AF) after electrical cardioversion (ECV). This study aimed to predict the recurrence of AF after ECV using machine learning of clinical features and electrocardiograms (ECGs) in persistent AF patients. METHODS We analyzed patients who underwent successful ECV for persistent AF. Machine learning was designed to predict patients with 1-month recurrence. Individual 12-lead ECGs were collected before and after ECV. Various clinical features were collected and trained the extreme gradient boost (XGBoost)-based model. Ten-fold cross-validation was used to evaluate the performance of the model. The performance was compared to the C-statistics of the selected clinical features. RESULTS Among 718 patients (mean age 63.5±9.3 years, men 78.8%), AF recurred in 435 (60.6%) patients after 1 month. With the XGBoost-based model, the areas under the receiver operating characteristic curves (AUROCs) were 0.57, 0.60, and 0.63 if the model was trained by clinical features, ECGs, and both (the final model), respectively. For the final model, the sensitivity, specificity, and F1-score were 84.7%, 28.2%, and 0.73, respectively. Although the AF duration showed the best predictive performance (AUROC, 0.58) among the clinical features, it was significantly lower than that of the final machine-learning model (p<0.001). Additional training of extended monitoring data of 15-minute single-lead ECG and photoplethysmography in available patients (n=261) did not significantly improve the model's performance. CONCLUSIONS Machine learning showed modest performance in predicting AF recurrence after ECV in persistent AF patients, warranting further validation studies.
Collapse
Affiliation(s)
- Soonil Kwon
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea
| | - Eunjung Lee
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, USA
| | - Hojin Ju
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea
| | - Hyo-Jeong Ahn
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea
| | - So-Ryoung Lee
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea
| | - Eue-Keun Choi
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
| | - Jangwon Suh
- Department of Intelligence and Information, Seoul National University, Seoul, Korea
| | - Seil Oh
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Wonjong Rhee
- Department of Intelligence and Information, Seoul National University, Seoul, Korea.
| |
Collapse
|
4
|
Wang S, Ju H, Bai Y, Wang L, Ding Q, Li P, Jiang X, Lin X. The prognostic value of splenic abnormalities in pretreatment 18F-FDG PET/CT in patients with complete response diffuse large B-cell lymphoma. Clin Radiol 2023; 78:375-380. [PMID: 36805286 DOI: 10.1016/j.crad.2023.01.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 01/23/2023] [Accepted: 01/24/2023] [Indexed: 02/05/2023]
Abstract
AIM To investigate whether spleen imaging characteristics of baseline 2-[18F]-fluoro-2-deoxy-d-glucose (18F-FDG) positron-emission tomography (PET)/computed tomography (CT) can help to predict the clinical outcome in complete response (CR) diffuse large B-cell lymphoma (DLBCL). MATERIALS AND METHODS Three hundred and six patients with DLBCL were enrolled in the study and divided into recurrence and non-recurrence groups. The splenic abnormalities were compared using the chi-square test and quantitative indexes were compared using the t-test. The Cox proportional hazard regression model was used for univariate and multivariate analysis. Kaplan-Meier curves and log-rank tests were used to compare progression-free survival (PFS). Propensity score matching (PSM) was used to match patients with and without splenic abnormalities according to age, gender, and initial Ann Arbor stage at a 1:2 ratio (52:104); then the recurrence and PFS results were compared again. RESULTS Age, international prognostic index (IPI), stage, splenomegaly, and focal splenic lesions were significantly different between the recurrence and non-recurrence groups. IPI, stage, baseline spleen mean standard uptake value (SUVmean)/liver SUVmean, splenomegaly, and focal lesions were selected by Cox single-factor analysis, and only focal lesions showed a statistical difference in terms of Cox multivariate analysis (p=0.022, hazard ratio [HR]: 2.843). After PSM, focal splenic lesions (n=20) were still statistically different (p=0.003) between the recurrence and non-recurrence groups, and this played an essential role in PFS forecasting (p=0.0004, HR: 3.767). CONCLUSION Focal splenic lesions were identified as an independent risk factor for the prognosis of DLBCL. Pretreatment splenomegaly and focal splenic lesions appeared to be related to the relapse and PFS of DLBCL patients. Focal splenic lesions still showed meaningful predictive value even with propensity matching.
Collapse
Affiliation(s)
- S Wang
- Department of Nuclear Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China
| | - H Ju
- Department of Nuclear Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China
| | - Y Bai
- Department of Nuclear Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China
| | - L Wang
- Department of Hematology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China
| | - Q Ding
- Institute of Natural Sciences, Shanghai Jiao Tong University, 200240, Shanghai, China
| | - P Li
- Department of Nuclear Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China
| | - X Jiang
- Department of Nuclear Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China; Department of Nuclear Medicine, Ruijin Hospital, Wuxi Branch, 214000, Wuxi, China
| | - X Lin
- Department of Nuclear Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China.
| |
Collapse
|
5
|
Ju H, Kim J, Lee S, Lee J, Kim G, Bae J. 535 A New Classification and Treatment Outcome of Hand Vitiligo: A Cluster Analysis. J Invest Dermatol 2022. [DOI: 10.1016/j.jid.2022.09.550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
6
|
He YX, Ju H, Li N, Jiang YF, Zhao WJ, Song TT, Ren WH. Association between hsa_circ_0006156 expression and incidence of gastric cancer. Eur Rev Med Pharmacol Sci 2021; 24:3030-3036. [PMID: 32271420 DOI: 10.26355/eurrev_202003_20667] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE To screen the differentially expressed circular ribonucleic acids (circRNAs) related to gastric cancer and to explore their associations with the clinicopathological features of gastric cancer. PATIENTS AND METHODS Cancer tissues of 50 gastric cancer patients undergoing surgical resection in our hospital from April 2015 to December 2018 were collected as an experimental group, while the para-carcinoma tissues were used as the control group. First, the differentially expressed circRNAs were screened by analyzing the circRNA profile in the microarray. Then, the expression of hsa_circ_0006156 in tissues was detected via Reverse Transcription-quantitative Polymerase Chain Reaction (RT-qPCR) in both groups. The potential associations of the relative expression level of hsa_circ_0006156 with clinicopathological features and prognosis were analyzed according to the clinical data of gastric cancer patients. RESULTS Six significantly downregulated circRNAs in gastric cancer patients were screened out. The results of RT-qPCR showed that the expression level of hsa_circ_0006156 was significantly lower in gastric cancer tissues than that in para-carcinoma tissues (p<0.05). Accordingly, 50 gastric cancer patients were divided into hsa_circ_0006156 high expression group and hsa_circ_0006156 low expression group based on the fold change of hsa_circ_0006156 in para-carcinoma tissues than that of gastric cancer tissues (fold change>3). The expression level of hsa_circ_0006156 was not correlated with the age and gender of gastric cancer patients (p>0.05) but correlated with the lymph node metastasis (p<0.05), nerve invasion (p<0.05), and degree of tumor differentiation (p<0.05). The expression level of hsa_circ_0006156 was also significantly associated with the progression-free survival (PFS) and overall survival (OS) of patients (p<0.05). According to the multivariate analysis of variance, the PFS of gastric cancer patients was associated with nerve invasion, lymph node metastasis, and hsa_circ_0006156 expression (relative risk coefficient=1.742, 2.329, and 3.003). Meanwhile, the OS was associated with lymph node metastasis, nerve invasion, degree of tumor differentiation, and hsa_circ_0006156 expression (relative risk coefficient =1.604, 2.405, 2.114, and 2.004). Moreover, the survival analysis revealed that PFS was markedly prolonged in the hsa_circ_0006156 high expression group compared with that in the hsa_circ_0006156 low expression group. CONCLUSIONS The expression of hsa_circ_0006156 substantially declines in gastric cancer tissues, which is related to the differentiation degree, presence, or absence of lymph node metastasis and prognosis of gastric cancer patients. Therefore, hsa_circ_0006156 may clinically serve as a biomarker for the prognostic prediction of gastric cancer patients.
Collapse
Affiliation(s)
- Y-X He
- Department of Gastroenterology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, China.
| | | | | | | | | | | | | |
Collapse
|
7
|
Kwon KY, Lee M, Ju H, Im K, Ahn MY. Clinical characteristics of dizzy patients with early Parkinson's disease. Parkinsonism Relat Disord 2020. [DOI: 10.1016/j.parkreldis.2020.06.191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
8
|
Ju H, Tan JY, Cao B, Song MQ, Tian ZB. Effects of miR-223 on colorectal cancer cell proliferation and apoptosis through regulating FoxO3a/BIM. Eur Rev Med Pharmacol Sci 2019; 22:3771-3778. [PMID: 29949152 DOI: 10.26355/eurrev_201806_15259] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Colorectal cancer is a common malignant tumor of the digestive tract. It frequently occurs at the junction of the rectum and sigmoid colon. It is characterized by high mortality and poor prognosis. Bcl-2 interacting mediator of cell death (BIM) plays a role in the regulation of cell proliferation and apoptosis, and involves in the pathogenesis of colorectal cancer. The transcription factor forkhead, transcription factor O subfamily 3a (FoxO3a) plays a role in the regulation of BIM expression and is associated to the pathogenesis of colorectal cancer. Bioinformatics analysis suggests that there is a targeted relationship between FoxO3a and microRNA-223 (miR-223). This study aims to investigate effects of miR-223 on the regulation of FoxO3a/BIM signaling pathway and colorectal cancer cell proliferation and apoptosis. MATERIALS AND METHODS Colorectal cancer cell line SW620 and normal colorectal epithelial cell line NCM460 were cultured in vitro. Dual luciferase reporter assay was used to validate the relationship between miR-223 and FoxO3a. Flow cytometry was adopted to detect apoptosis. EdU staining was applied to test cell proliferation. Western blot was selected to determine FoxO3a and BIM protein expressions. RESULTS There was targeted regulatory relationship between miR-223 and FoxO3a. MiRa-223 up-regulated, FoxO3a and BIM expressions reduced, and cell proliferation was enhanced in SW620 cells compared with NCM460 cells. MiR-223 inhibitor or pIRES2-FoxO3a transfection significantly increased FoxO3a and BIM expressions, attenuated cell proliferation, and enhanced cell apoptosis. CONCLUSIONS MiR-223 targeted inhibited expression of FoxO3. Down-regulating the expression of miR-223, it increased the expressions of FoxO3a and BIM, weakened SW620 cells proliferation and induced apoptosis.
Collapse
Affiliation(s)
- H Ju
- Department of Gastroenterology, Affiliated Hospital Of Qingdao University, Qingdao, Shandong, China.
| | | | | | | | | |
Collapse
|
9
|
Lee J, Lee R, Ju H, Kim M, Kim J, Bang C, Han J, Lee J, Woo Y, Bae J. 104 Willingness-to-pay of patients with chronic skin diseases: A pilot study. J Invest Dermatol 2019. [DOI: 10.1016/j.jid.2019.07.108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
10
|
Lee J, Lee R, Ju H, Kim G, Bae J, Choi C. 090 Narrow-band ultraviolet B phototherapy does not increase the risk of skin cancer in patients with vitiligo: A nationwide population-based retrospective cohort study. J Invest Dermatol 2019. [DOI: 10.1016/j.jid.2019.07.094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
11
|
Ju H, Liu L, Wu W, Cai Y, Lu X. The relationship between primary tumor regression grade and lymph nodes status in local advanced rectal cancer after neoadjuvant chemoradiation therapy. Ann Oncol 2018. [DOI: 10.1093/annonc/mdy151.305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
12
|
Li WH, Hui CJ, Ju H. Expression and significance of vWF, GMP-140 and ADAMTS13 in patients with aneurysmal subarachnoid hemorrhage. Eur Rev Med Pharmacol Sci 2017; 21:4350-4356. [PMID: 29077161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
OBJECTIVE The aim of this study was to investigate the role of the von Willebrand factor (vWF) in patients with aneurysmal subarachnoid hemorrhage (aSAH), platelet membrane glycoprotein-140 (GMP-140). The aim is also to discover the expression and clinical significance of von Willebrand factor (vWF) cleaving protease (ADAMTS13). PATIENTS AND METHODS 83 patients with aSAH were selected from January 2014 to December 2016. The patients were divided into cerebral vasospasm group (CVS group) (n = 37) and no convulsion group (non-CVS group) (n = 46); delayed cerebral ischemia group (DCI group) (n = 31) and non-delayed cerebral ischemia group (non-DCI group) (n = 52). Also, the different aneurysm diameter group included 43 patients in < 5 mm group, 29 patients in 5-10 mm group, 11 patients in > 10 mm group. The number of patients in the good prognosis group and the poor prognosis group were 49 and 34, respectively. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of vWF, GMP-140, and ADAMTS13 in plasma of aSAH patients, and the correlation between the indexes was analyzed. RESULTS The repeated measures analysis of variance showed that there was no significant difference in plasma vWF, GMP-140, and ADAMTS13 levels in each group of the aSAH patients (p < 0.05). The vWF level of the CVS group was higher than that of the non-CVS group on day 4 and day 10. The GMP-140 level of the CVS group was higher than that of the non-CVS group on day 1, day 4 and day 10. And the ADAMTS13 level was lower than that of the non-CVS group on day 1 and day 10. The difference was statistically significant (p < 0.05). The plasma vWF level of DCI group was higher than that of the non-DCI group on day 1 and day 4. The plasma GMP-140 level at day 4 was higher than that of the non-DCI group. The plasma ADAMTS13 level at day 1 was lower than that in the non-DCI group. The difference was significant (p < 0.05). The plasma vWF level in > 10 mm group was higher than that in < 5 mm group and 5-10 mm group at day 1 and day 4. The plasma vWF level in 5-10 mm group was higher than that in < 5 mm group at day 4. The plasma GMP-140 levels in > 10 mm group were higher than that in < 5 mm group and 5-10 mm group at day 1 and d ay 4. The plasma GMP-140 level in 5-10 mm group was higher than that in < 5 mm group at day 1. The plasma ADAMTS13 level in > 10 mm group was lower than that in < 5 mm group and 5-10 mm group on day 1. Moreover, the plasma ADAMTS13 level in 5-10 mm group was lower than that in < 5 mm group: p < 0.05. The plasma vWF level in the good prognosis group was lower than that in the poor prognosis group on day 4 and day 10. On day 1, day 4, and day 10, the level of GMP-140 was lower than that of the poor prognosis group. The ADAMTS13 level on day 1 and day 4 was higher than that in the poor prognosis group. The difference was statistically significant (p < 0.05). Pearson product moment correlation analysis showed that the plasma vWF level was positively correlated with GMP-140 at day 1 (r = 0.334, p < 0.05), negatively correlated with ADAMTS13 (r = -0.426, p < 0.05), and GMP-140 was negatively correlated with ADAMTS13 (r = -0.398, p < 0.05). At day 4, plasma vWF was positively correlated with GMP-140 (r = 0.278, p < 0.05), negatively correlated with ADAMTS13 (r = -0.311, p < 0.05), and GMP-140 was negatively correlated with ADAMTS13 (r = -0.235, p < 0.05). At day 10, there was no significant correlation between vWF, GMP-140, and ADAMTS13 (p > 0.05). CONCLUSIONS VWF, GMP-140, and ADAMTS13 were correlated with the diameters and prognoses of CVS, DCI, aneurysms. Combined detection can help to evaluate the condition of patients with aSAH, so as to provide a guide for clinical treatment and prognosis.
Collapse
Affiliation(s)
- W-H Li
- Department of Neurosurgery, Affiliated Hospital of Qinghai University, Xining, Qinghai, China.
| | | | | |
Collapse
|
13
|
Ju H, Hart RA. Hidden blood loss in anterior lumbar interbody fusion (ALIF) surgery. Orthop Traumatol Surg Res 2016; 102:67-70. [PMID: 26776101 DOI: 10.1016/j.otsr.2015.10.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 09/14/2015] [Accepted: 10/14/2015] [Indexed: 02/02/2023]
Abstract
BACKGROUND A retrospective study was performed to determine the factors affecting the total perioperative blood loss during anterior lumbar interbody fusion (ALIF). Measurements of intraoperative blood loss underestimate the true blood loss during surgery. Our research project was to examine the hidden blood loss in lumbar spine surgery. Hidden blood loss in elective knee and hip replacement surgeries range between 100% and 30%. Hidden blood loss was about 40% in posterior spine surgery. METHODS The factors analyzed included gender, body mass index (BMI), duration of surgery, type of surgery, aspiration, and number of fusion levels. Estimated blood loss (EBL) was obtained from the clinical records of patients as the blood collected from suctioning and the cumulative weight of the saturated sponges. Actual blood loss (ABL) was calculated from the estimated blood volume and hemoglobin level of patients. Hidden blood loss was calculated as the difference between ABL and EBL. RESULTS Seventy-eight consecutive patients who underwent ALIF were reviewed. The average values (mean±SD) for EBL and ABL were 700.1±562.3mL and 1150.6±770.0mL, respectively (P=0.001, Student's t-test). The hidden blood loss averaged 39.2% of the ABL. According to linear regression analysis, surgical duration, type of surgery, and the inclusion of the L4/5 level were independent factors contributing to the ABL (P<0.05), whereas BMI and gender did not correlate with ABL or EBL. CONCLUSIONS ALIF is associated with substantial perioperative hidden blood loss. Length of surgery, type of surgery, and the inclusion of L4/5 in the procedure are significant risk factors for increased blood loss. LEVEL OF EVIDENCE Level IV: retrospective or historical series.
Collapse
Affiliation(s)
- H Ju
- Department of Orthopedics, Guangzhou First Municipal People's Hospital, Guangzhou, Guangdong, China; Department of Orthopedics and Rehabilitation, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97201, United States.
| | - R A Hart
- Department of Orthopedics and Rehabilitation, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97201, United States.
| |
Collapse
|
14
|
Lee MS, Ju H, Song JW, Park CG. Kinematic Model-Based Pedestrian Dead Reckoning for Heading Correction and Lower Body Motion Tracking. Sensors (Basel) 2015; 15:28129-53. [PMID: 26561814 PMCID: PMC4701272 DOI: 10.3390/s151128129] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 10/05/2015] [Accepted: 11/02/2015] [Indexed: 11/23/2022]
Abstract
In this paper, we present a method for finding the enhanced heading and position of pedestrians by fusing the Zero velocity UPdaTe (ZUPT)-based pedestrian dead reckoning (PDR) and the kinematic constraints of the lower human body. ZUPT is a well known algorithm for PDR, and provides a sufficiently accurate position solution for short term periods, but it cannot guarantee a stable and reliable heading because it suffers from magnetic disturbance in determining heading angles, which degrades the overall position accuracy as time passes. The basic idea of the proposed algorithm is integrating the left and right foot positions obtained by ZUPTs with the heading and position information from an IMU mounted on the waist. To integrate this information, a kinematic model of the lower human body, which is calculated by using orientation sensors mounted on both thighs and calves, is adopted. We note that the position of the left and right feet cannot be apart because of the kinematic constraints of the body, so the kinematic model generates new measurements for the waist position. The Extended Kalman Filter (EKF) on the waist data that estimates and corrects error states uses these measurements and magnetic heading measurements, which enhances the heading accuracy. The updated position information is fed into the foot mounted sensors, and reupdate processes are performed to correct the position error of each foot. The proposed update-reupdate technique consequently ensures improved observability of error states and position accuracy. Moreover, the proposed method provides all the information about the lower human body, so that it can be applied more effectively to motion tracking. The effectiveness of the proposed algorithm is verified via experimental results, which show that a 1.25% Return Position Error (RPE) with respect to walking distance is achieved.
Collapse
Affiliation(s)
- Min Su Lee
- Department of Mechanical and Aerospace Engineering, Automation and Systems Research Institute, Seoul National University, Seoul 151-744, Korea.
| | - Hojin Ju
- Department of Mechanical and Aerospace Engineering, Automation and Systems Research Institute, Seoul National University, Seoul 151-744, Korea.
| | - Jin Woo Song
- BK21Plus Transformative Training Program for Creative Mechanical and Aerospace Engineers, Department of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-744, Korea.
| | - Chan Gook Park
- Department of Mechanical and Aerospace Engineering, Automation and Systems Research Institute, Seoul National University, Seoul 151-744, Korea.
| |
Collapse
|
15
|
Kim T, Ju H, Kim S, Harrell A, Trifiletti D, Libby B, Read P. Novel Remote Controlled and Self-contained Audiovisual-Aided Interactive System With iPad Mini for Immobilizing Claustrophobic Patients With Head and Neck Cancer. Int J Radiat Oncol Biol Phys 2015. [DOI: 10.1016/j.ijrobp.2015.07.2041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
16
|
Ju H, Shin H, Son C, Park K, Choi I. 3-Iodothyronamine-mediated metabolic suppression increases the phosphorylation of AMPK and induces fuel choice toward lipid mobilization. Horm Metab Res 2015; 47:605-10. [PMID: 25372779 DOI: 10.1055/s-0034-1394380] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Despite broad medical application, induction of artificial hypometabolism in vitro and its biochemical consequence have been rarely addressed. This study aimed to elucidate whether 3-iodothyronamine (T1AM) induces hypometabolism in an in vitro model with activation of AMP-activated protein kinase (AMPK) and whether it leads to a switch in primary fuel from carbohydrates to lipids as observed in in vivo models. Mouse C2C12 myotube and T1AM, a natural derivative of thyroid hormone, were used in this study. The oxygen consumption rate (OCR) decreased in a dose-dependent manner in response to 0-100 μM T1AM for up to 10 h. Upon 6-h of exposure to 75 μM T1AM, the OCR was reduced to 60 vs. ~ 95% for the control. The intracellular [AMP]/[ATP] was 1.35-fold higher in T1AM-treated cells. RT-PCR and immunoblotting analyses revealed that treated cells had upregulated p-AMPK/AMPK (1.8-fold), carnitine palmitoyl transferase 1 mRNA, and pyruvate dehydrogenase kinase, and downregulated acetyl CoA carboxylase (0.4-fold) and pyruvate dehydrogenase phosphatase. The treated cells had darker periodic acid-Schiff staining with 1.2-fold greater glycogen content than controls. Taken together, the hypometabolic response of myotubes to T1AM was dramatic and accompanied by increases in both the relative abundance of AMP and AMPK activation, and fuel choice favoring lipids over carbohydrates. These results are consistent with the general trends observed for rodent models and true hibernators.
Collapse
Affiliation(s)
- H Ju
- Division of Biological Science and Technology, College of Science and Technology, Yonsei University, Wonju, Gangwon-Do, Republic of Korea
| | - H Shin
- Division of Biological Science and Technology, College of Science and Technology, Yonsei University, Wonju, Gangwon-Do, Republic of Korea
| | - C Son
- Medical Research Institute, Sungkyunkwan University, Clinical Research Center, Samsung Biomedical Research Institute, Irwon-dong 50, Gangnam-gu, Seoul, Republic of Korea
| | - K Park
- Medical Research Institute, Sungkyunkwan University, Clinical Research Center, Samsung Biomedical Research Institute, Irwon-dong 50, Gangnam-gu, Seoul, Republic of Korea
| | - I Choi
- Division of Biological Science and Technology, College of Science and Technology, Yonsei University, Wonju, Gangwon-Do, Republic of Korea
| |
Collapse
|
17
|
Lv J, Pan Y, Li X, Cheng D, Ju H, Tian J, Shi H, Zhang Y. Study on the distribution and elimination of the new hormone irisin in vivo: new discoveries regarding irisin. Horm Metab Res 2015; 47:591-5. [PMID: 25757030 DOI: 10.1055/s-0035-1547261] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Irisin is a newly discovered factor that is secreted by skeletal muscle and plays an important role in the homeostasis and metabolism of energy balance. This study used irisin radiolabeled with (125)I and small-animal SPECT/CT imaging to investigate the metabolic elimination and distribution of irisin in vivo. Irisin was labeled with (125)I using the Iodogen method. Small-animal SPECT/CT imaging was performed on C57/B16 mice at 15, 30, 60, 120, and 240 min after receiving a tail vein injection, and the radioactive distribution in the organs of mice was determined at 15, 60, and 120 min. Small-animal SPECT/CT imaging revealed the highest level of radioactivity in the gallbladder followed by the liver and kidney. Radioactivity decreased gradually with time in all organs. The radioactive distribution in the mice organs also showed that the highest %ID/g was in the gallbladder followed by the kidney and liver, and decreased gradually with time. The radioactivity in the gastric system reached its highest level at 60 min. Finally, our study showed the metabolic clearance of (125)I-irisin is achieved primarily through the hepatobiliary and renal system and provided the basis for the clinical application of irisin.
Collapse
Affiliation(s)
- J Lv
- Department of Nuclear Medicine, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Y Pan
- Department of Nuclear Medicine, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - X Li
- Department of Nuclear Medicine, Zhongshan Hospital, School of Medicine, Fudan University, Shanghai, China
| | - D Cheng
- Department of Nuclear Medicine, Zhongshan Hospital, School of Medicine, Fudan University, Shanghai, China
| | - H Ju
- Department of Nuclear Medicine, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - J Tian
- Department of Endocrine, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - H Shi
- Department of Nuclear Medicine, Zhongshan Hospital, School of Medicine, Fudan University, Shanghai, China
| | - Y Zhang
- Department of Nuclear Medicine, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| |
Collapse
|
18
|
Liu Y, Feng J, Qian J, Zhu Y, Ju H, Li D. P-240 Did the change of mRNA copy numbers in peripheral blood influence their relationship with colorectal cancer patients' prognosis? Ann Oncol 2015. [DOI: 10.1093/annonc/mdv233.237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
19
|
Liu Z, Ju H, Zhu Y, Li D, Fan Y. Co-suturing SURGICEL(®) and colonic fat to achieve hemostasis in presacral hemorrhage. Tech Coloproctol 2015; 19:365-6. [PMID: 25943464 DOI: 10.1007/s10151-015-1312-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 03/19/2015] [Indexed: 10/23/2022]
Affiliation(s)
- Z Liu
- Department of Colorectal Cancer, Zhejiang Cancer Hospital, 38 Guangji Road, Hangzhou, 310022, Zhejiang Province, China
| | | | | | | | | |
Collapse
|
20
|
Choi Y, Kim W, Ham W, Cho K, Cho N, Lee H, Lee J, Ju H. MP-2.12: Transurethral Layer-Section of Muscle Invasive Bladder Cancer: Accurate T Staging and Bladder Preservation in a Selected T2 Bladder Cancer. Urology 2008. [DOI: 10.1016/j.urology.2008.08.179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
21
|
Ju H, Zhang S, Lenstra D, de Waardt H, Tangdiongga E, Khoe G, Dorren H. SOA-based all-optical switch with subpicosecond full recovery. Opt Express 2005; 13:942-947. [PMID: 19494957 DOI: 10.1364/opex.13.000942] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We investigate all-optical switching in a multi-quantum-well semiconductor optical amplifier-based nonlinear polarization switch using optical pulses with duration of 200 fs at a central wavelength of 1520 nm. We show full recovery of the switch within 600 fs, in both the gain and absorption regime. We discuss the switching and recovery mechanisms using numerical simulations that are in qualitatively good agreement with our experimental data.
Collapse
|
22
|
Buchanan RJ, Wang S, Ju H. Analyses of the minimum data set: comparisons of nursing home residents with multiple sclerosis to other nursing home residents. Mult Scler 2002; 8:512-22. [PMID: 12474994 DOI: 10.1191/1352458502ms823oa] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
This research compares nursing home residents with multiple sclerosis (MS) at admission to other nursing home residents using the minimum data set (MDS). These comparisons include sociodemographic characteristics and health status measures, as well as treatments and procedures received. We analysed 14,009 admission assessments in the MDS for residents with MS between June 22, 1998 and December 31, 2000. We also analysed 440,642 MDS admission assessments for all residents admitted to nursing homes during the year 2000, with any admission assessments for residents with MS excluded from this comparison group. Residents with MS were significantly younger at admission than other recently admitted residents. In addition, residents with MS tended to be significantly more physically disabled and also less cognitively impaired than other residents at admission, based on analyses of several measures of physical disability and cognitive performance. Nursing homes caring for residents with MS should provide services and programs, including mental health care, that address the needs of these younger, more physically disabled, and more cognitvely intact residents.
Collapse
Affiliation(s)
- R J Buchanan
- Department of Health Policy and Management, School of Rural Public Health, The Texas A&M University System Health Science Center, College Station, Texas 77843-1266, USA.
| | | | | |
Collapse
|
23
|
Zou X, Chen Y, Wang Y, Luo J, Zhang Q, Zhang X, Yang Y, Ju H, Shen Y, Lao W, Xu S, Du M. Production of cloned goats from enucleated oocytes injected with cumulus cell nuclei or fused with cumulus cells. Cloning 2002; 3:31-7. [PMID: 11918840 DOI: 10.1089/152045501300189312] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
This study was designed to produce cloned goats from cumulus cells. Cloning donor nuclei were from cumulus cells either freshly isolated or cultured in vitro. Enucleated oocytes were either injected with cumulus cell nuclei without piezo-driven manipulator (injection method) or fused with cumulus cells (fusion method). The survival rate of cloned embryos, obtained by injection, was higher than that derived from fusion (62.7 and 45.9%, respectively). Two cloned goats were derived by fusion with in vitro cultured cumulus cells without starvation, but died shortly after natural birth, from respiratory difficulties. Their birth weights (2.23 kg and 2.03 kg) were within the normal range (2.0-2.7 kg) and postmortem analysis revealed no morphological abnormalities. The third cloned goat, derived by injection of nuclei from freshly isolated cumulus cells, weighed 3.3 kg at birth, and was 37% overweight compared with the average weight of the same species. This goat is healthy and well as this paper is being prepared. Nested PCR-RFLP analysis confirmed that all the cloned goats were derived from the donor cells.
Collapse
Affiliation(s)
- X Zou
- The Babraham Institute, Babraham, Cambridge, United Kingdom
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Ju H, Gros R, You X, Tsang S, Husain M, Rabinovitch M. Conditional and targeted overexpression of vascular chymase causes hypertension in transgenic mice. Proc Natl Acad Sci U S A 2001; 98:7469-74. [PMID: 11416217 PMCID: PMC34692 DOI: 10.1073/pnas.131147598] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
We cloned a rat vascular chymase (RVCH) from smooth muscle cells (SMCs) that converts angiotensin I to II and is up-regulated in SMC from spontaneously hypertensive vs. normotensive rats. To determine whether increased activity of RVCH is sufficient to cause hypertension, transgenic mice were generated with targeted conditional expression of RVCH to SMC, with the use of the tetracycline-controlled transactivator (tTA). We confirmed conditional expression of RVCH by mRNA, protein, and chymase activity in the absence, but not in the presence, of dietary doxycycline. The systolic blood pressure (mmHg), measured by carotid artery cannulation at 10-12 weeks of age, was higher in tTA+/RVCH+ mice than in nonbinary transgenic littermates (136 +/- 4 vs. 109 +/- 3) (P < 0.05), as were the diastolic and mean pressures. Hypertension was completely reversed by doxycycline, suggesting a causal link with chymase expression. Medial thickening of mesenteric arteries from tTA+/RVCH+ mice vs. littermates (0.82 +/- 0.1 vs. 0.42 +/- 0.02) (P < 0.05) was associated with increased SMC proliferation, as judged by positive immunoreactivity, with the use of an antibody to the proliferating cell nuclear antigen. These structural changes were prevented by doxycycline. Perfusion myography of mesenteric arteries from tTA+/RVCH+ mice also revealed increased vasoconstriction in response to phenylephrine and impaired metacholine-induced vasodilatation when compared with littermate controls or with the doxycyline-treated group. Our studies suggest that up-regulation of this vascular chymase is sufficient to cause a hypertensive arteriopathy, and that RVCH may be a candidate gene and a therapeutic target in patients with high blood pressure.
Collapse
Affiliation(s)
- H Ju
- Division of Cardiovascular Research, Research Institute, The Hospital for Sick Children, Center for Cardiovascular Research, The Toronto Hospital, University of Toronto, Toronto, ON, Canada M5G 1X8
| | | | | | | | | | | |
Collapse
|
25
|
Harris MB, Ju H, Venema VJ, Liang H, Zou R, Michell BJ, Chen ZP, Kemp BE, Venema RC. Reciprocal phosphorylation and regulation of endothelial nitric-oxide synthase in response to bradykinin stimulation. J Biol Chem 2001; 276:16587-91. [PMID: 11340086 DOI: 10.1074/jbc.m100229200] [Citation(s) in RCA: 288] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Endothelial nitric-oxide synthase (eNOS) is phosphorylated at Ser-1179 (bovine sequence) by Akt after growth factor or shear stress stimulation of endothelial cells, resulting in increased eNOS activity. Purified eNOS is also phosphorylated at Thr-497 by purified AMP-activated protein kinase, resulting in decreased eNOS activity. We investigated whether bradykinin (BK) stimulation of bovine aortic endothelial cells (BAECs) regulates eNOS through Akt activation and Ser-1179 or Thr-497 phosphorylation. Akt is transiently activated in BK-stimulated BAECs. Activation is blocked completely by wortmannin and LY294002, inhibitors of phosphatidylinositol 3-kinase, suggesting that Akt activation occurs downstream from phosphatidylinositol 3-kinase. BK stimulates a transient phosphorylation of eNOS at Ser-1179 that is correlated temporally with a transient dephosphorylation of eNOS at Thr-497. Phosphorylation at Ser-1179, but not dephosphorylation at Thr-497, is blocked by wortmannin and LY294002. BK also stimulates a transient nitric oxide (NO) release from BAECs with a time-course similar to Ser-1179 phosphorylation and Thr-497 dephosphorylation. NO release is not altered by wortmannin. BK-stimulated dephosphorylation of Thr-497 and NO release are blocked by the calcineurin inhibitor, cyclosporin A. These data suggest that BK activation of eNOS in BAECs primarily involves deinhibition of the enzyme through calcineurin-mediated dephosphorylation at Thr-497.
Collapse
Affiliation(s)
- M B Harris
- Vascular Biology Center, Department of Pediatrics, Medical College of Georgia, Augusta, Georgia 30912, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Abstract
While greater than 80% of angiotensin II (Ang II) formation in the human heart and greater than 60% in arteries appears to result from chymase activity, no cardiovascular cell-expressed chymase has been previously reported. We now describe the cloning of a full-length cDNA encoding a novel chymase from rat vascular smooth muscle cells. The cDNA encompasses 953 nucleotides, encodes 247 amino acids, and exhibits 74% and 80% homology in amino acid sequence to rat mast cell chymase I and II, respectively. Southern blot analysis indicates that the rat vascular chymase is encoded by a separate gene. This chymase was induced in hypertrophied rat pulmonary arteries, with 11-fold and 8-fold higher chymase mRNA levels in aortic and pulmonary artery smooth muscle cells from spontaneously hypertensive than in corresponding tissues from normotensive rats. We assayed the activity of the endogenous enzyme and of a recombinant, epitope-tagged chymase in transfected smooth muscle cells and showed that Ang II production from Ang I can be inhibited with chymostatin, but not EDTA or captopril. Spontaneously hypertensive rats show elevated chymase expression and increased chymostatin-inhibitable angiotensin-converting activity, suggesting a possible role for this novel enzyme in the pathophysiology of hypertension.
Collapse
MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- Cell Line
- Chymases
- Cloning, Molecular
- DNA Primers/genetics
- DNA, Complementary/genetics
- Humans
- Hypertension/enzymology
- Hypertension/genetics
- Mast Cells/enzymology
- Molecular Sequence Data
- Muscle, Smooth, Vascular/enzymology
- Pulmonary Artery/enzymology
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Rats, Inbred SHR
- Rats, Inbred WKY
- Rats, Sprague-Dawley
- Sequence Homology, Amino Acid
- Serine Endopeptidases/genetics
- Serine Endopeptidases/metabolism
- Up-Regulation
Collapse
Affiliation(s)
- C Guo
- Division of Cardiovascular Research, Research Institute, The Hospital for Sick Children, University of Toronto, Toronto, Ontario M5G 1X8, Canada
| | | | | | | | | | | |
Collapse
|
27
|
Abstract
The electrolyte effects on the electrochemical behaviors of osmium complex polymer modified electrodes were investigated by a comparison between two osmium complexes, [Os(bpy)2(PVI)10Cl]Cl (Os-PVI10) and [Os(bpy)2(PVP)10Cl]Cl (Os-PVP10). The electrode process at Os-PVI10 modified electrodes is reaction-controlled, while a diffusion-controlled electrode process exists at Os-PVP10 modified electrodes. Both the cation and anion in supporting electrolytes strongly affect their electrochemical behaviors, such as the redox potential, wave shape and peak current. These phenomena are attributed to a change in the film structure and polymer swelling in various supporting electrolytes. The influence of electrolyte anions on the electrochemical behaviors is related to their hydrophobicity. The electrode process of Os-PVP10 depends on the pH value of solutions, exhibiting different electron transfer mechanisms.
Collapse
Affiliation(s)
- H Ju
- Department of Chemistry, Institute of Analytical Science, Nanjing University, China.
| | | | | |
Collapse
|
28
|
Ju H, Venema VJ, Liang H, Harris MB, Zou R, Venema RC. Bradykinin activates the Janus-activated kinase/signal transducers and activators of transcription (JAK/STAT) pathway in vascular endothelial cells: localization of JAK/STAT signalling proteins in plasmalemmal caveolae. Biochem J 2000; 351:257-64. [PMID: 10998369 PMCID: PMC1221357 DOI: 10.1042/0264-6021:3510257] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Bradykinin (BK) is an important physiological regulator of endothelial cell function. In the present study, we have examined the role of the Janus-activated kinase (JAK)/signal transducers and activators of transcription (STAT) pathway in endothelial signal transduction through the BK B2 receptor (B2R). In cultured bovine aortic endothelial cells (BAECs), BK activates Tyk2 of the JAK family of tyrosine kinases. Activation results in the tyrosine phosphorylation and subsequent nuclear translocation of STAT3. BK also activates the mitogen-activated p44 and p42 protein kinases, resulting in STAT3 serine phosphorylation. Furthermore, Tyk2 and STAT3 form a complex with the B2R in response to BK stimulation. Under basal conditions, Tyk2, STAT3 and the B2R are localized either partially or entirely in endothelial plasmalemmal caveolae. Following BK stimulation of BAECs, however, the B2R and STAT3 are translocated out of caveolae. Taken together, these data suggest that BK activates the JAK/STAT pathway in endothelial cells and that JAK/STAT signalling proteins are localized in endothelial caveolae. Moreover, caveolar localization of the B2R and STAT3 appears to be regulated in an agonist-dependent manner.
Collapse
MESH Headings
- Active Transport, Cell Nucleus/drug effects
- Animals
- Aorta
- Bradykinin/pharmacology
- Cattle
- Caveolae/drug effects
- Caveolae/metabolism
- Caveolin 1
- Caveolins/metabolism
- Cell Nucleus/drug effects
- Cell Nucleus/metabolism
- Cells, Cultured
- DNA-Binding Proteins/metabolism
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/enzymology
- Endothelium, Vascular/metabolism
- Enzyme Activation/drug effects
- MAP Kinase Signaling System/drug effects
- Mitogen-Activated Protein Kinases/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/enzymology
- Muscle, Smooth, Vascular/metabolism
- Phosphorylation/drug effects
- Phosphoserine/metabolism
- Phosphotyrosine/metabolism
- Protein Binding/drug effects
- Protein-Tyrosine Kinases
- Proteins/metabolism
- Receptor, Bradykinin B2
- Receptors, Bradykinin/metabolism
- STAT3 Transcription Factor
- Trans-Activators/metabolism
Collapse
Affiliation(s)
- H Ju
- Vascular Biology Center, Medical College of Georgia, Augusta, GA 30912-2500, USA
| | | | | | | | | | | |
Collapse
|
29
|
Harris MB, Ju H, Venema VJ, Blackstone M, Venema RC. Role of heat shock protein 90 in bradykinin-stimulated endothelial nitric oxide release. Gen Pharmacol 2000; 35:165-70. [PMID: 11744239 DOI: 10.1016/s0306-3623(01)00104-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Previously we described ENAP-1, a 90-kDa protein that is tyrosine-phosphorylated in endothelial cells in response to bradykinin (BK) stimulation and is associated with endothelial nitric oxide synthase (eNOS). Subsequently, other investigators demonstrated that eNOS interacts with heat shock protein 90 (Hsp90) following stimulation of endothelial cells with vascular endothelial growth factor (VEGF), histamine, or fluid shear stress. Therefore, we tested the hypotheses that ENAP-1 and Hsp90 are the same protein and that BK activation of eNOS is dependent on Hsp90. Immunoblotting of immunoprecipitated Hsp90 with anti-phosphotyrosine antibody shows that Hsp90 is tyrosine-phosphorylated in response to BK stimulation of bovine aortic endothelial cells (BAECs). Coimmunoprecipitation of Hsp90 with anti-eNOS antibody reveals a Hsp90-eNOS complex in endothelial cells under basal conditions that is increased following BK stimulation. Taken together with the tyrosine phosphorylation data, these data suggest that ENAP-1 is Hsp90. BK-stimulated nitric oxide (NO) release is completely blocked by pretreatment with geldanamycin, a specific inhibitor of Hsp90, illustrating the importance of the Hsp90-eNOS interaction. In vitro binding assays with Hsp90-glutathione-S-transferase fusion proteins show direct binding of eNOS with the middle domain (residues 259-615) of Hsp90.
Collapse
Affiliation(s)
- M B Harris
- Vascular Biology Center, Medical College of Georgia, Augusta, GA 30912-2500, USA
| | | | | | | | | |
Collapse
|
30
|
Han L, Yan F, Wang S, Ju H, Yang Z, Yan J. [Primary identification of organic compounds in soybean rhizospheric soil on continuous and alternate cropping and their allelopathy on soybean seed germination]. Ying Yong Sheng Tai Xue Bao 2000; 11:582-6. [PMID: 11767682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Organic compounds extracted with ethanol (OCEWE) from soybean rhizospheic soil on continuous and alternate cropping at pod-string were identified by gas chromatography-mass spectrometry (GC-MS). The results showed the compounds mainly include organic acids, alcohol, acetone, aldehyde, naphthalene phenyl and furan hydrocarbon, many of which were reported as allelochemcals. Under this experiment condition, OCEWE did not show any allelopathy on soybean seed germination and radicle growth, which might be related with their critical toxicity concentrations. In addition, the relationship between allelopathy and barrier on soybean continuous and alternate cropping was also discussed.
Collapse
Affiliation(s)
- L Han
- Department of Agronomy, Quartermaster University of PLA, Changchun 130062.
| | | | | | | | | | | |
Collapse
|
31
|
Chun M, Kang S, Ryu H, Chang K, Oh Y, Ju H, Lee E. Modified partial hyperfractionation in radiotherapy for bulky uterine cervical cancer: reduction of overall treatment time. Int J Radiat Oncol Biol Phys 2000; 47:973-7. [PMID: 10863067 DOI: 10.1016/s0360-3016(00)00539-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PURPOSE The purpose of this study was to assess the feasibility and toxicity of modified fractionation of external beam radiation with the intention of reducing the overall treatment time (OT) by 1 week in cervical cancer. METHODS AND MATERIALS Thirty-one patients (Group 1, n = 31) with bulky cervical cancer (>/= 4 cm with Stage II and III, >/= 5 cm with Stage IB2) were entered into the twice a day (b.i. d.) protocol (18 Gy/10 fx in 2 weeks followed by 18 Gy/12 fx, b.i.d. in 6 days, then midline block at 36 Gy with 45 Gy to the whole pelvis and 51-59 Gy to the parametrium). These patients underwent high-dose-rate brachytherapy with 4 Gy/fx x 7 to point A, biweekly. During the same period, patients with non-bulky tumors (Group 2, n = 31) received conventional treatment and similar brachytherapy. RESULTS The OT of Group 1 was 7 weeks or less in 61.3%, 7.1-8 weeks in 29%, and more than 8 weeks in 9.7% (19.4%, 51.6%, and 29% in Group 2, respectively, p = 0.003). Incidences of acute complications and treatment breaks were similar in both groups. Late complication (rectal bleeding) occurred only in Group 1 (13%, 4/31), but was self-limited. Locoregional failures occurred within 2 years after completion of radiation therapy in both groups (16% and 13% in Group 1 and 2, respectively, with minimum and median follow-ups of 2 years and 34 months). CONCLUSION Partial hyperfractionation on the third week of radiation permitted patients to finish their treatment with shorter OT without excessive acute complications and with acceptable grade 2 late rectal bleeding complications. This treatment scheme may be an effective method for the improvement of local control of bulky cervical cancer.
Collapse
Affiliation(s)
- M Chun
- Department of Radiation Oncology, Ajou University Hospital, Suwon, Korea.
| | | | | | | | | | | | | |
Collapse
|
32
|
Amiri F, Venema VJ, Wang X, Ju H, Venema RC, Marrero MB. Hyperglycemia enhances angiotensin II-induced janus-activated kinase/STAT signaling in vascular smooth muscle cells. J Biol Chem 1999; 274:32382-6. [PMID: 10542280 DOI: 10.1074/jbc.274.45.32382] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have shown previously that angiotensin II (Ang II) activates the janus-activated kinase (JAK)/signal transducers and activators of transcription (STAT) pathway in vascular smooth muscle cells (VSMCs) and that activation of the JAK/STAT pathway is required for Ang II induction of VSMC proliferation. In the present study, we examined the effects of hyperglycemia (HG) on Ang II-induced JAK/STAT signaling events in cultured VSMCs. HG increases Ang II-induced JAK2 tyrosine phosphorylation and promotes a partial tyrosine phosphorylation of the enzyme under basal conditions. In addition, HG increases both basal and Ang II-induced complex formation of JAK2 with the Ang II AT(1) receptor. The extent of STAT1 and STAT3 tyrosine and serine phosphorylation are also increased under HG conditions. Furthermore, the tyrosine phosphorylation and activities of the SHP-1 and SHP-2 tyrosine phosphatases, enzymes that regulate Ang II-induced JAK2 tyrosine phosphorylation, are altered by HG. SHP-1, which is responsible for JAK2 tyrosine dephosphorylation in VSMC, is completely deactivated in HG, resulting in a prolonged duration of JAK2 phosphorylation under HG conditions. HG also enhances Ang II induction of VSMC proliferation. Taken together, these data suggest that HG augments Ang II induction of VSMC proliferation by increasing signal transduction through the JAK/STAT pathway.
Collapse
Affiliation(s)
- F Amiri
- Vascular Biology Center, Medical College of Georgia, Augusta, Georgia 30912, USA
| | | | | | | | | | | |
Collapse
|
33
|
Marrero MB, Venema VJ, Ju H, He H, Liang H, Caldwell RB, Venema RC. Endothelial nitric oxide synthase interactions with G-protein-coupled receptors. Biochem J 1999; 343 Pt 2:335-40. [PMID: 10510297 PMCID: PMC1220558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
The endothelial nitric oxide synthase (eNOS) is activated in response to stimulation of endothelial cells by a number of vasoactive substances including, bradykinin (BK), angiotensin II (Ang II), endothelin-1 (ET-1) and ATP. In the present study we have used in vitro activity assays of purified eNOS and in vitro binding assays with glutathione S-transferase fusion proteins to show that the capacity to bind and inhibit eNOS is a common feature of membrane-proximal regions of intracellular domain 4 of the BK B2, the Ang II AT1 and the ET-1 ETB receptors, but not of the ATP P2Y2 receptor. Phosphorylation of serine or tyrosine residues in the eNOS-interacting region of the B2 receptor results in a loss of eNOS inhibition due to a decrease in the binding affinity of the receptor domain for the eNOS enzyme. Furthermore, the B2 receptor is transiently phosphorylated on tyrosine residues in cultured endothelial cells in response to BK stimulation. Phosphorylation occurs during the time in which eNOS transiently dissociates from the receptor accompanied by a transient increase in nitric oxide production. Taken together, these data support the hypotheses that eNOS is regulated in endothelial cells by reversible and inhibitory interactions with G-protein-coupled receptors and that these interactions can be modulated by receptor phosphorylation.
Collapse
MESH Headings
- Animals
- Bradykinin/pharmacology
- Calmodulin/metabolism
- Cells, Cultured
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/enzymology
- Endothelium, Vascular/metabolism
- Enzyme Activation/drug effects
- GTP-Binding Proteins/metabolism
- Humans
- Ligands
- Nitric Oxide/metabolism
- Nitric Oxide Synthase/antagonists & inhibitors
- Nitric Oxide Synthase/metabolism
- Nitric Oxide Synthase Type III
- Peptide Fragments/chemistry
- Peptide Fragments/metabolism
- Peptide Fragments/pharmacology
- Phosphorylation/drug effects
- Phosphotyrosine/metabolism
- Protein Binding/drug effects
- Receptor, Angiotensin, Type 1
- Receptor, Angiotensin, Type 2
- Receptor, Bradykinin B2
- Receptor, Endothelin B
- Receptors, Angiotensin/chemistry
- Receptors, Angiotensin/metabolism
- Receptors, Bradykinin/chemistry
- Receptors, Bradykinin/metabolism
- Receptors, Endothelin/chemistry
- Receptors, Endothelin/metabolism
- Receptors, Purinergic P2/chemistry
- Receptors, Purinergic P2/metabolism
- Receptors, Purinergic P2Y2
- Recombinant Fusion Proteins/chemistry
- Recombinant Fusion Proteins/metabolism
Collapse
Affiliation(s)
- M B Marrero
- Vascular Biology Center, Medical College of Georgia, Augusta, GA 30912-2500, USA
| | | | | | | | | | | | | |
Collapse
|
34
|
Liang H, Venema VJ, Wang X, Ju H, Venema RC, Marrero MB. Regulation of angiotensin II-induced phosphorylation of STAT3 in vascular smooth muscle cells. J Biol Chem 1999; 274:19846-51. [PMID: 10391929 DOI: 10.1074/jbc.274.28.19846] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Ligand binding to the angiotensin II (Ang II) AT1 receptor on vascular smooth muscle cells (VSMCs) activates the Janus-activated kinase (JAK)/signal transducers and activators of transcription (STAT) pathway. We have shown previously that the JAK2 tyrosine kinase and the Src family p59 Fyn tyrosine kinase are required for Ang II-induced STAT1 tyrosine phosphorylation in VSMCs. The mitogen-activated protein kinase phosphatase, MKP-1, is required for STAT1 tyrosine dephosphorylation. In the present study, using specific enzyme inhibitors and antisense oligonucleotides, we show that Ang II-induced tyrosine phosphorylation and nuclear translocation of STAT3 in VSMCs is mediated by p60 c-Src, whereas tyrosine dephosphorylation is mediated by calcineurin. Calcineurin is activated in response to Ang II stimulation of VSMCs and is translocated to the nucleus. In addition, we show that Ang II-induced serine phosphorylation of STAT3 in VSMCs is mediated by mitogen-activated protein kinase and that dephosphorylation is mediated by protein phosphatase 2A (PP2A). PP2A translocates to the nucleus in response to Ang II stimulation of VSMCs and forms a complex with STAT3 in an Ang II-dependent manner.
Collapse
Affiliation(s)
- H Liang
- Vascular Biology Center, Medical College of Georgia, Augusta, Georgia 30912, USA
| | | | | | | | | | | |
Collapse
|
35
|
Abstract
The sensitivity and precision of two fully automated enzyme immunoassays, a chemiluminescent enzyme immunoassay (CLEIA) and an enzyme-linked immunosorbent assay (ELISA), for the determination of the ovarian carcinoma antigen CA 125 were evaluated by comparison with an immunoradiometric assay (IRMA). Sera were obtained from patients with ovarian carcinoma (N = 28 before treatment and N = 24 after treatment), digestive system cancer (N = 21 before treatment) and from healthy women (N = 90). The CLEIA showed a good agreement with the IRMA in terms of the positivity rate, accuracy and assay linearity, whereas the ELISA gave some false positive results. The mean value of CA 125 in the sera of healthy women was 14, 16 and 20 U/ml determined using the CLEIA, IRMA and ELISA procedures with standard deviations (SD) of 6.9, 7.3 and 8.8 U/ml, respectively. Both the reproducibility and precision of the CLEIA with coefficients of variation (CV) of 4.6% intra-assay and 7.6% inter-assay were better than those of the ELISA with CV of 6.2% intra-assay and 15.2% inter-assay (N = 16). We conclude that the CLEIA is the preferable method for CA 125 determinations and the diagnosis of ovarian carcinoma.
Collapse
Affiliation(s)
- G Yan
- Department of Chemistry, Nanjing University, China
| | | | | | | |
Collapse
|
36
|
Hao J, Ju H, Zhao S, Junaid A, Scammell-La Fleur T, Dixon IM. Elevation of expression of Smads 2, 3, and 4, decorin and TGF-beta in the chronic phase of myocardial infarct scar healing. J Mol Cell Cardiol 1999; 31:667-78. [PMID: 10198196 DOI: 10.1006/jmcc.1998.0902] [Citation(s) in RCA: 162] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have previously shown that non-myocytes present in healed 8-week infarct scar overexpress transduction proteins required for initiating the elevated deposition of structural matrix proteins in this tissue. Other work suggests that TGF-beta 1 may be involved in cardiac fibrosis and myocyte hypertrophy. However, the significance of the altered TGF-beta signaling in heart failure in the chronic phase of post-myocardial infarction (MI), particularly in the ongoing remodeling of the infarct scar, remains unexplored. Patterns of cardiac TGF beta 1 and Smad 2, 3, and 4 protein expression were investigated 8 weeks after MI and were compared to relative collagen deposition in border tissues (containing remnent myocytes) and the infarct scar (non-myocytes). Both TGF-beta 1 mRNA abundance and protein levels were significantly increased in the infarct scar v control values, and this trend was positively correlated to increased collagen type I expression. Cardiac Smad 2, 3, and 4 proteins were significantly increased in border and scar tissues v control values. Immunofluorescent studies indicated that Smad proteins localized proximal to the cellular nuclei present in the infarct scar. Decorin mRNA abundance was elevated in border and infarct scar, and the pattern of decorin immunostaining was markedly altered in remote remnant heart and scar v staining patterns of control sections. Expression of T beta RI (53 kDa) protein was significantly reduced in the scar, while the 75 kDa and 110 kDa isoforms of T beta RII were unchanged and significantly increased in scar, respectively. These results indicate that TGF-beta/Smad signaling may be involved in the remodeling of the infarct scar after the completion of wound healing per se, via ongoing stimulation of matrix deposition.
Collapse
Affiliation(s)
- J Hao
- Laboratory of Molecular Cardiology, St. Boniface General Hospital Research Centre, Faculty of Medicine, University of Manitoba, Winnipeg, Canada
| | | | | | | | | | | |
Collapse
|
37
|
Peterson DJ, Ju H, Hao J, Panagia M, Chapman DC, Dixon IM. Expression of Gi-2 alpha and Gs alpha in myofibroblasts localized to the infarct scar in heart failure due to myocardial infarction. Cardiovasc Res 1999; 41:575-85. [PMID: 10435029 DOI: 10.1016/s0008-6363(98)00264-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
OBJECTIVE Patients surviving large transmural myocardial infarction (MI) are at risk for congestive heart failure with attendant alteration of ventricular geometry and scar remodeling. Altered Gi-2 alpha and Gs alpha protein expression may be involved in cardiac remodeling associated with heart failure, however their expression in scar tissue remains unclear. METHODS MI was produced in Sprague-Dawley rats by ligation of the left coronary artery. Gi-2 alpha and Gs alpha protein concentration, localization and mRNA abundance were noted in surviving left ventricle remote to the infarct, in border and in scar tissues from 8 week post-MI hearts with moderate heart failure. RESULTS We observed a 4.5- and 5.0-fold increase in immunoreactive Gi-2 alpha protein concentration occurs in the border and scar regions vs. control values, respectively, in 8-week post-MI rat hearts. Similarly, immunoreactive Gs alpha protein concentration was increased 3.4- and 8.2-fold, respectively, in these tissues vs. controls. Double-fluorescence labeling and phenotyping studies revealed that both Gi-2 alpha and Gs alpha proteins were localized to myofibroblasts in the infarct scar and to viable myocytes bordering the scar. Northern analysis revealed that the Gi-2 alpha/GAPDH ratio was increased in both viable and scar regions (1.24- and 1.85-fold respectively) from experimental hearts when compared to sham-operated control values when compared to noninfarcted left ventricle, the value of this ratio in scar tissue was elevated approximately 1.5 fold. The Gs alpha/GAPDH ratio was significantly increased (1.28-fold) only in the scar region vs. control. CONCLUSION Our results indicate a marked increase in the expression of Gi-2 alpha and Gs alpha from myofibroblasts of the infarct scar as well as remnant myocytes bordering the scar in 8-week post-MI rat hearts. We suggest that these changes may be associated with ongoing remodeling in the infarct scar in chronic post-MI phase of this experimental model.
Collapse
MESH Headings
- Analysis of Variance
- Animals
- Blotting, Northern
- Blotting, Western
- Fibroblasts/metabolism
- Fibroblasts/pathology
- Fluorescent Antibody Technique
- GTP-Binding Protein alpha Subunits, Gi-Go/analysis
- GTP-Binding Protein alpha Subunits, Gi-Go/genetics
- GTP-Binding Protein alpha Subunits, Gi-Go/metabolism
- GTP-Binding Protein alpha Subunits, Gs/analysis
- GTP-Binding Protein alpha Subunits, Gs/genetics
- GTP-Binding Protein alpha Subunits, Gs/metabolism
- GTP-Binding Proteins/analysis
- GTP-Binding Proteins/genetics
- GTP-Binding Proteins/metabolism
- Gene Expression
- Heart Failure/metabolism
- Heart Failure/pathology
- Male
- Myocardial Infarction/metabolism
- Myocardial Infarction/pathology
- Myocardium/metabolism
- Myocardium/pathology
- RNA, Messenger/analysis
- Rats
- Rats, Sprague-Dawley
Collapse
Affiliation(s)
- D J Peterson
- Molecular Cardiology Laboratory, St. Boniface General Hospital Research Centre, Faculty of Medicine, University of Manitoba, Winnipeg, Canada
| | | | | | | | | | | |
Collapse
|
38
|
Abstract
Prolyl 4-hydroxylase catalyzes the hydroxylation of collagen pro-alpha chains for the deposition of cardiac collagen. The effect of prolyl 4-hydroxylase on synthesis and degradation of collagen was studied in cultured adult cardiac fibroblasts using mimosine, a prolyl 4-hydroxylase inhibitor. Mimosine inhibited [3H]thymidine incorporation in cultured fibroblasts in a dose-dependent manner (100-600 microM). Immunofluorescence in fibroblasts and biochemical detection of mature type I collagen in culture serum revealed a strong inhibition of synthesis and secretion of mature collagens, respectively, in the presence of 200 microM mimosine. Western blot analysis for procollagen was carried out in cultured fibroblasts, and 200 microM mimosine treatment was associated with increased intracellular accumulation of procollagen from 4.14+/-0.27 to 10. 19+/-0.37 (arbitrary units). Immunofluorescence studies confirmed a marked increase of intracellular procollagens in fibroblasts treated with mimosine, which suggests a loss of coordinated monomeric procollagen synthesis and secretion of triple helical mature collagens. Modest inhibition of collagen type I mRNA abundance was observed in mimosine-treated fibroblasts, whereas no effect was noted for mRNAs of collagen type III, alpha-prolyl 4-hydroxylase or beta-prolyl 4-hydroxylase when compared to untreated control values. Treatment of fibroblasts with 200 microM mimosine was associated with elevation of matrix metalloproteinase (MMP)-9 activity. The cytotoxicity of mimosine treatment was found minimal at the concentrations indicated above. Thus the antifibrotic effects induced by mimosine on cultured adult cardiac fibroblasts was associated with inhibition of prolyl 4-hydroxylase and diminished extracellular secretion of procollagen, despite the reactive elevation of intracellular procollagen synthesis. We suggest that specific inhibition of prolyl 4-hydroxylase may provide a novel therapeutic approach for the modulation of cardiac fibrosis.
Collapse
Affiliation(s)
- H Ju
- Molecular Cardiology Laboratory, Institute of Cardiovascular Sciences, St. Boniface General Hospital Research Centre, Faculty of Medicine, University of Manitoba, Winnipeg, Man. R2H 2A6, Canada
| | | | | | | |
Collapse
|
39
|
Marrero MB, Venema VJ, Ju H, Eaton DC, Venema RC. Regulation of angiotensin II-induced JAK2 tyrosine phosphorylation: roles of SHP-1 and SHP-2. Am J Physiol 1998; 275:C1216-23. [PMID: 9814969 DOI: 10.1152/ajpcell.1998.275.5.c1216] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Angiotensin II (ANG II) exerts its effects on vascular smooth muscle cells through G protein-coupled AT1 receptors. ANG II stimulation activates the Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway by inducing tyrosine phosphorylation, activation, and association of JAK2 with the receptor. Association appears to be required for JAK2 phosphorylation. In the present study, electroporation experiments with neutralizing anti-Src homology phosphatase-1 (SHP-1) and anti-SHP-2 antibodies and time course determinations of SHP-1 and SHP-2 activation and complexation with JAK2 suggest that the tyrosine phosphatases, SHP-1 and SHP-2, have opposite roles in ANG II-induced JAK2 phosphorylation. SHP-1 appears responsible for JAK2 dephosphorylation and termination of the ANG II-induced JAK/STAT cascade. SHP-2 appears to have an essential role in JAK2 phosphorylation and initiation of the ANG II-induced JAK/STAT cascade leading to cell proliferation. The motif in the AT1 receptor that is required for association with JAK2 is also required for association with SHP-2. Furthermore, SHP-2 is required for JAK2-receptor association. SHP-2 may thus play a role as an adaptor protein for JAK2 association with the receptor, thereby facilitating JAK2 phosphorylation and activation.
Collapse
MESH Headings
- Amino Acid Substitution
- Angiotensin II/pharmacology
- Animals
- Antibodies/pharmacology
- Cells, Cultured
- Electroporation
- Heart/physiology
- Heart Ventricles
- Intracellular Signaling Peptides and Proteins
- Janus Kinase 2
- Male
- Myocardium/cytology
- Myocardium/enzymology
- Phosphorylation
- Phosphotyrosine/metabolism
- Point Mutation
- Protein Phosphatase 1
- Protein Tyrosine Phosphatase, Non-Receptor Type 1
- Protein Tyrosine Phosphatase, Non-Receptor Type 11
- Protein Tyrosine Phosphatase, Non-Receptor Type 6
- Protein Tyrosine Phosphatases/genetics
- Protein Tyrosine Phosphatases/metabolism
- Protein-Tyrosine Kinases/metabolism
- Proto-Oncogene Proteins
- Rats
- Rats, Sprague-Dawley
- Receptor, Angiotensin, Type 1
- Receptor, Angiotensin, Type 2
- Receptors, Angiotensin/drug effects
- Receptors, Angiotensin/physiology
- Recombinant Proteins/metabolism
- SH2 Domain-Containing Protein Tyrosine Phosphatases
- Signal Transduction/drug effects
- Signal Transduction/physiology
- src Homology Domains
Collapse
Affiliation(s)
- M B Marrero
- Vascular Biology Center, Medical College of Georgia, Augusta 30912, Georgia, USA
| | | | | | | | | |
Collapse
|
40
|
Abstract
It has been shown previously that the endothelial nitric-oxide synthase (eNOS) interacts reversibly with the plasmalemmal caveolae structural protein, caveolin-1. The eNOS-caveolin-1 interaction inhibits eNOS catalytic activity. In the present study, we show that eNOS also participates in reversible inhibitory interactions with the G protein-coupled bradykinin B2 receptor. eNOS and the B2 receptor are coimmunoprecipitated from endothelial cell lysates by antibodies directed against either of the two proteins. A glutathione S-transferase fusion protein containing intracellular domain 4 of the receptor is bound by purified recombinant eNOS in in vitro binding assays. The fusion protein selectively inhibits the activity of purified eNOS. A synthetic peptide corresponding to membrane-proximal residues 310-334 in intracellular domain 4 also potently inhibits eNOS activity (IC50 < 1 microM). Treatment of cultured endothelial cells with bradykinin or Ca2+ ionophore promotes a rapid dissociation of the eNOS.B2 receptor complex. These data demonstrate that the bradykinin B2 receptor physically associates with eNOS in a ligand- and Ca2+-dependent manner. Reversible and inhibitory membrane-docking interactions of eNOS, therefore, are not restricted to those with caveolin-1 but also occur with the bradykinin B2 receptor.
Collapse
Affiliation(s)
- H Ju
- Department of Pediatrics, Medical College of Georgia, Augusta, Georgia 30912, USA
| | | | | | | |
Collapse
|
41
|
Venema VJ, Ju H, Sun J, Eaton DC, Marrero MB, Venema RC. Bradykinin stimulates the tyrosine phosphorylation and bradykinin B2 receptor association of phospholipase C gamma 1 in vascular endothelial cells. Biochem Biophys Res Commun 1998; 246:70-5. [PMID: 9600070 DOI: 10.1006/bbrc.1998.8574] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Bradykinin (BK) B2 receptor signaling involves activation of phospholipase C (PLC). PLC activation by other receptors consists of either allosteric activation of PLC beta isoforms by G-proteins or tyrosine phosphorylation of PLC gamma isoforms. Because the B2 receptor is a G-protein-coupled receptor, it has been assumed that the receptor signals through PLC beta. In the present study, however, we have found that BK stimulation of IP3 production and the Ca2+ signal in endothelial cells is dependent on tyrosine phosphorylation. Furthermore, stimulation of B2 receptors in these cells is accompanied by a transient tyrosine phosphorylation of PLC gamma 1. Phosphorylation is correlated with increased IP3 production and association of PLC gamma 1 with the C-terminal intracellular domain of the B2 receptor. The B2 receptor can thus physically associate with intracellular proteins other than G-proteins. Activation of PLC gamma isoforms, rather than PLC beta isoforms, may, therefore, be primarily responsible for BK-stimulated IP3 generation in endothelial cells.
Collapse
MESH Headings
- Animals
- Bradykinin/pharmacology
- Cattle
- Cells, Cultured
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Enzyme Activation
- Inositol 1,4,5-Trisphosphate/biosynthesis
- Isoenzymes/metabolism
- Phospholipase C gamma
- Phosphorylation
- Pyrazoles/pharmacology
- Pyrimidines/pharmacology
- Receptor, Angiotensin, Type 1
- Receptor, Angiotensin, Type 2
- Receptor, Bradykinin B2
- Receptors, Angiotensin/metabolism
- Receptors, Bradykinin/metabolism
- Recombinant Fusion Proteins/metabolism
- Signal Transduction
- Type C Phospholipases/metabolism
- Tyrosine/metabolism
- src-Family Kinases/antagonists & inhibitors
Collapse
Affiliation(s)
- V J Venema
- Department of Pediatrics, Medical College of Georgia, Augusta 30912, USA.
| | | | | | | | | | | |
Collapse
|
42
|
Venema RC, Ju H, Venema VJ, Schieffer B, Harp JB, Ling BN, Eaton DC, Marrero MB. Angiotensin II-induced association of phospholipase Cgamma1 with the G-protein-coupled AT1 receptor. J Biol Chem 1998; 273:7703-8. [PMID: 9516477 DOI: 10.1074/jbc.273.13.7703] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
An early event in signaling by the G-protein-coupled angiotensin II (Ang II) AT1 receptor in vascular smooth muscle cells is the tyrosine phosphorylation and activation of phospholipase Cgamma1 (PLCgamma1). In the present study, we show that stimulation of this event by Ang II in vascular smooth muscle cells is accompanied by binding of PLCgamma1 to the AT1 receptor in an Ang II- and tyrosine phophorylation-dependent manner. The PLCgamma1-AT1 receptor interaction appears to depend on phosphorylation of tyrosine 319 in a YIPP motif in the C-terminal intracellular domain of the AT1 receptor and binding of the phosphorylated receptor by the most C-terminal of two Src homology 2 domains in PLCgamma1. PLCgamma1 thus binds to the same site in the receptor previously identified for binding by the SHP-2 phosphotyrosine phosphatase.JAK2 tyrosine kinase complex. A single site in the C-terminal tail of the AT1 receptor can, therefore, be bound in a ligand-dependent manner by two different downstream effector proteins. These data demonstrate that G-protein-coupled receptors can physically associate with intracellular proteins other than G proteins, creating membrane-delimited signal transduction complexes similar to those observed for classic growth factor receptors.
Collapse
Affiliation(s)
- R C Venema
- Vascular Biology Center, Department of Pediatrics, Medical College of Georgia, Augusta, Georgia 30912, USA
| | | | | | | | | | | | | | | |
Collapse
|
43
|
Abstract
BACKGROUND Large transmural myocardial infarction (MI) leads to maladaptive cardiac remodeling and places patients at increased risk of congestive heart failure. Angiotensin II, endothelin, and alpha1-adrenergic receptor agonists are implicated in the development of cardiac hypertrophy, interstitial fibrosis, and heart failure after MI. Because these agonists are coupled to and activate Gq alpha protein in the heart, the aim of the present study was to investigate Gq alpha expression and function in cardiac remodeling and heart failure after MI. METHODS AND RESULTS MI was produced in rats by ligation of the left coronary artery, and Gq alpha protein concentration, localization, and mRNA abundance were noted in surviving left ventricle remote from the infarct and in border and scar tissues from 8-week post-MI hearts with moderate heart failure. Immunohistochemical staining localized elevated Gq alpha expression in the scar and border tissues. Western analysis confirmed significant upregulation of Gq alpha proteins in these regions versus controls. Furthermore, Northern analysis revealed that the ratios of Gq alpha/GAPDH mRNA abundance in both scar and viable tissues from experimental hearts were significantly increased versus controls. Increased expression of phospholipase C (PLC)-beta1 and PLC-beta3 proteins was apparent in the scar and viable tissues after MI versus controls and is associated with increased PLC-beta1 activity in experimental hearts. Furthermore, inositol 1,4,5-tris-phosphate is significantly increased in the border and scar tissues compared with control values. CONCLUSIONS Upregulation of the Gq alpha/PLC-beta pathway was observed in the viable, border, and scar tissues in post-MI hearts. Gq alpha and PLC-beta may play important roles in scar remodeling as well as cardiac hypertrophy and fibrosis of the surviving tissue in post-MI rat heart. It is suggested that the Gq alpha/PLC-beta pathway may provide a possible novel target for altering postinfarct remodeling.
Collapse
Affiliation(s)
- H Ju
- Laboratory of Molecular Cardiology, Institute of Cardiovascular Sciences, St Boniface General Hospital Research Centre, Faculty of Medicine, University of Manitoba, Winnipeg, Canada
| | | | | | | | | |
Collapse
|
44
|
Venema VJ, Ju H, Zou R, Venema RC. Interaction of neuronal nitric-oxide synthase with caveolin-3 in skeletal muscle. Identification of a novel caveolin scaffolding/inhibitory domain. J Biol Chem 1997; 272:28187-90. [PMID: 9353265 DOI: 10.1074/jbc.272.45.28187] [Citation(s) in RCA: 194] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Neuronal nitric-oxide synthase (nNOS) has been shown previously to interact with alpha1-syntrophin in the dystrophin complex of skeletal muscle. In the present study, we have examined whether nNOS also interacts with caveolin-3 in skeletal muscle. nNOS and caveolin-3 are coimmunoprecipitated from rat skeletal muscle homogenates by antibodies directed against either of the two proteins. Synthetic peptides corresponding to the membrane-proximal caveolin-3 residues 65-84 and 109-130 and homologous caveolin-1 residues 82-101 and 135-156 potently inhibit the catalytic activity of purified, recombinant nNOS. Purified nNOS also binds to a glutathione S-transferase-caveolin-1 fusion protein in in vitro binding assays. In vitro binding is completely abolished by preincubation of nNOS with either of the two caveolin-3 inhibitory peptides. Interactions between nNOS and caveolin-3, therefore, appear to be direct and to involve two distinct caveolin scaffolding/inhibitory domains. Other caveolin-interacting enzymes, including endothelial nitric-oxide synthase and the c-Src tyrosine kinase, are also potently inhibited by each of the four caveolin peptides. Inhibitory interactions mediated by two different caveolin domains may thus be a general feature of enzyme docking to caveolin proteins in plasmalemmal caveolae.
Collapse
Affiliation(s)
- V J Venema
- Department of Pediatrics, Medical College of Georgia, Augusta, Georgia 30912,
| | | | | | | |
Collapse
|
45
|
Abstract
Complementary DNA clones encoding human membrane-bound aminopeptidase P (AmP) were isolated by reverse transcription-polymerase chain reaction (RT-PCR) of human kidney and lung poly (A)+ RNA. Comparison of the human AmP sequence to that of the pig shows significant evolutionary divergence with only 83% amino acid sequence identity between the two species. Northern hybridization analysis and RT-PCR suggests that the soluble and membrane-bound forms of human AmP are products of two distinct genes or, through alternative splicing, have different C-terminal sequences.
Collapse
Affiliation(s)
- R C Venema
- Vascular Biology Center, Medical College of Georgia, Augusta 30912-2500, USA
| | | | | | | | | |
Collapse
|
46
|
Abstract
OBJECTIVE Previous work has shown that cardiac fibrosis occurs after myocardial infarction (MI) in non-infarcted ventricular tissue and that this event is associated with abnormal cardiac function. Our aim was to investigate the effect of AT1 receptor blockade on cardiac collagen remodeling in post-MI rat heart remote from the infarct site by addressing collagen mRNA abundance, posttranslational hydroxylation of collagen monomers, and mature collagen deposition. Prolyl 4-hydroxylase (PH) mediates hydroxylation of procollagen alpha-chains in the endoplasmic reticulum of cardiac fibroblasts and thus regulates the downstream formation and secretion of helical procollagen molecules. METHODS The effects of losartan (15 mg/kg/day) on collagen deposition and mRNA abundance were monitored in viable left and right ventricles in sham-operated (control) and experimental groups in the presence or absence of losartan. Immunoreactive PH concentration in viable tissues as well as cardiac function in control and experimental groups was determined by ELISA. RESULTS Immunohistochemical staining and 4-hydroxyproline assays confirmed that losartan treatment attenuates fibrosis in experimental hearts. Northern analysis revealed that losartan treatment of 1, 2, or 4 week experimental groups had no effect on collagen mRNA abundance compared to untreated post-MI rats. On the other hand, immunoreactive PH concentration was significantly decreased in the post-MI group treated with losartan. Determination of cardiac mass and cardiac function revealed that losartan treatment was associated with attenuated cardiac hypertrophy and improved left ventricular (LV) function in experimental animals. CONCLUSIONS AT1 blockade is associated with a significant decrease in cardiac fibrosis in treated post-MI rats, and this trend is positively correlated to a significant decrease in immunoreactive PH compared to untreated experimental animals. The expression of cardiac PH may be regulated by angiotensin via AT1 receptor activation, and the suppression of PH with losartan treatment may be an important mechanism for modulation of collagen deposition in the post-MI rat heart.
Collapse
Affiliation(s)
- H Ju
- Molecular Cardiology Laboratory, St. Boniface General Hospital Research Centre, Faculty of Medicine, University of Manitoba, Winnipeg, Canada
| | | | | | | |
Collapse
|
47
|
Abstract
Endothelial nitric-oxide synthase (eNOS) and caveolin-1 are associated within endothelial plasmalemmal caveolae. It is not known, however, whether eNOS and caveolin-1 interact directly or indirectly or whether the interaction affects eNOS activity. To answer these questions, we have cloned the bovine caveolin-1 cDNA and have investigated the eNOS-caveolin-1 interaction in an in vitro binding assay system using glutathione S-transferase (GST)-caveolin-1 fusion proteins and baculovirus-expressed bovine eNOS. We have also mapped the domains involved in the interaction using an in vivo yeast two-hybrid system. Results obtained using both in vitro and in vivo protein interaction assays show that both N- and C-terminal cytosolic domains of caveolin-1 interact directly with the eNOS oxygenase domain. Interaction of eNOS with GST-caveolin-1 fusion proteins significantly inhibits enzyme catalytic activity. A synthetic peptide corresponding to caveolin-1 residues 82-101 also potently and reversibly inhibits eNOS activity by interfering with the interaction of the enzyme with Ca2+/calmodulin (CaM). Regulation of eNOS in endothelial cells, therefore, may involve not only positive allosteric regulation by Ca2+/CaM, but also negative allosteric regulation by caveolin-1.
Collapse
Affiliation(s)
- H Ju
- Vascular Biology Center, Department of Pediatrics, Medical College of Georgia, Augusta, Georgia 30912, USA
| | | | | | | |
Collapse
|
48
|
Venema VJ, Zou R, Ju H, Marrero MB, Venema RC. Caveolin-1 detergent solubility and association with endothelial nitric oxide synthase is modulated by tyrosine phosphorylation. Biochem Biophys Res Commun 1997; 236:155-61. [PMID: 9223444 DOI: 10.1006/bbrc.1997.6921] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Caveolin-1 and endothelial nitric oxide synthase (eNOS) are associated within endothelial caveolae. We have shown previously that eNOS is translocated to the detergent-insoluble, cytoskeletal fraction of bovine aortic endothelial cells (BAEC) in response to bradykinin (BK)-stimulation or tyrosine phosphatase inhibition. In the present study, we have examined whether caveolin-1 is similarly translocated in response to these or other stimuli. Exposure of BAEC to the eNOS-activating agonists, BK, histamine, or ATP produces transient increases in the amounts of detergent-insoluble caveolin-1. Increases in insolubility are blocked by tyrosine kinase inhibitors and are potently mimicked by tyrosine phosphatase inhibitors. Increased insolubility is accompanied by an increased association of caveolin-1 with eNOS and inhibition of eNOS catalytic activity. Agonist-activation of eNOS in endothelial cells thus appears to involve tyrosine phosphorylation-dependent changes in the interaction of eNOS with caveolin-1. Increased interaction of eNOS with caveolin-1 may deactivate the enzyme subsequent to its activation by Ca2+/calmodulin.
Collapse
Affiliation(s)
- V J Venema
- Vascular Biology Center, Department of Pediatrics, Medical College of Georgia, Augusta 30912, USA
| | | | | | | | | |
Collapse
|
49
|
Dixon IM, Ju H, Reid NL, Scammell-La Fleur T, Werner JP, Jasmin G. Cardiac collagen remodeling in the cardiomyopathic Syrian hamster and the effect of losartan. J Mol Cell Cardiol 1997; 29:1837-50. [PMID: 9236138 DOI: 10.1006/jmcc.1997.0420] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Although increased deposition of collagen proteins has been described in cardiomyopathy, little is known of the temporal relationship between events in collagen gene transcription and the occurrence of cardiac fibrosis, the removal of collagen by matrix metalloproteinases (MMPs), or of the regulation of these events by angiotensin AT1 receptors in this disease. We sought to study steady-state collagen mRNA abundance and the deposition of specific collagen subtypes in right and left ventricular muscle of Syrian cardiomyopathic (CMP) hamsters at different stages of cardiomyopathy. Using zymography, we also investigated the gelatinolytic activities of different MMPs to gain some information about collagen removal in experimental hearts. Finally, we investigated the effect of AT1 receptor blockade (losartan) on collagen remodeling. We observed that the mRNA levels of types I and III collagens were significantly increased in all four experimental groups (35, 65, 120, and 200 day) in left ventricular tissue when compared to control (F1-beta strain) values. The mRNA levels of these collagen species in experimental right ventricular tissue samples were only elevated significantly in the 35 and 200 day experimental groups when compared to controls. Fibrillar collagen deposition was elevated in left and right ventricular CMP samples after a lag period from the occurrence of corresponding increases in mRNA abundance. Although 2-week losartan treatment of 65, 120 and 200 day experimental groups had no significant effect on left ventricular fibrillar collagen concentration or collagen mRNA abundance when compared to vehicle-infused CMP hamsters, AT1 receptor blockade was associated with complete regression of cardiac hypertrophy. Both MMP-1 (54 kDa band) and MMP-2 (58 and 62 kDa bands) activities were increased in left ventricular CMP tissues at 65, 120 and 200 days when compared to F1-beta controls. Losartan treatment was associated with significant attenuation of MMP activities in cardiomyopathic samples at 65 and 120 days. Thus, elevation of mRNA abundance of fibrillar collagen genes occurs at very early stages in this model of cardiomyopathy, and corresponding collagen proteins were subsequently deposited in the cardiac interstitium at later stages. As collagen concentration was significantly increased in later stages of cardiomyopathy studied herein (120 and 200 day groups), our data support the hypothesis that collagen synthesis exceeds the capacity of collagen removal during the progression of cardiomyopathy. Nevertheless, cardiac collagen remodeling may be facilitated by elevated MMP activity in cardiomyopathic stages in this experimental model, and we suggested that attenuation of MMP activity in the presence of losartan may be a cardioprotective mechanism of this agent.
Collapse
Affiliation(s)
- I M Dixon
- Institute of Cardiovascular Sciences, St Boniface General Hospital Research Centre, University of Manitoba, Winnipeg, Manitoba, R2H 2A6, Canada
| | | | | | | | | | | |
Collapse
|
50
|
Venema RC, Ju H, Zou R, Ryan JW, Venema VJ. Subunit interactions of endothelial nitric-oxide synthase. Comparisons to the neuronal and inducible nitric-oxide synthase isoforms. J Biol Chem 1997; 272:1276-82. [PMID: 8995432 DOI: 10.1074/jbc.272.2.1276] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Endothelial nitric-oxide synthase (eNOS) is comprised of two identical subunits. Each subunit has a bidomain structure consisting of an N-terminal oxygenase domain containing heme and tetrahydrobiopterin (BH4) and a C-terminal reductase domain containing binding sites for FAD, FMN, and NADPH. Each subunit is also myristoylated and contains a calmodulin (CaM)-binding site located between the oxygenase and reductase domains. In this study, wild-type and mutant forms of eNOS have been expressed in a baculovirus system, and the quaternary structure of the purified enzymes has been analyzed by low temperature SDS-PAGE. eNOS dimer formation requires incorporation of the heme prosthetic group but does not require myristoylation or CaM or BH4 binding. In order to identify domains of eNOS involved in subunit interactions, we have also expressed eNOS oxygenase and reductase domain fusion proteins in a yeast two-hybrid system. Corresponding human neuronal NOS (nNOS) and murine inducible NOS (iNOS) fusion proteins have also been expressed. Comparative analysis of NOS domain interactions shows that subunit association of eNOS and nNOS involves not only head to head interactions of oxygenase domains but also tail to tail interactions of reductase domains and head to tail interactions between oxygenase and reductase domains. In contrast, iNOS subunit association involves only oxygenase domain interactions.
Collapse
Affiliation(s)
- R C Venema
- Department of Pediatrics, Medical College of Georgia, Augusta 30912, USA.
| | | | | | | | | |
Collapse
|