Serum Connective Tissue Growth Factor Research Articles

Serum Connective Tissue Growth Factor (CTGF) As a Potential Biomarker for Diagnosis of Rheumatoid Arthritis

Serum Connective Tissue Growth Factor (CTGF) As a Potential Biomarker for Diagnosis of Rheumatoid Arthritis

Serum levels of endothelin-1 and connective tissue growth factor are elevated in patients with atrial fibrillation and correlated with relapse following radiofrequency ablation

To investigate the changes in serum levels of endothelin-1 (ET-1) and connective tissue growth factor (CTGF) in patients with atrial fibrillation (AF) and their value for predicting recurrence of AF after radiofrequency ablation (RFCA). Sixty-six patients with paroxysmal AF (PaAF) and 72 with persistent AF (PaAF) admitted in our hospital were recruited as AF group and 80 patients with sinus rhythm as the control group, and in all the participants, serum levels of ET-1 and CTGF were measured using ELISA and Western blotting. From 6 patients with AF and 6 with sinus rhythm undergoing cardiac surgery in our hospital, tissue samples of the right atrial appendage were taken intraoperatively for observation of structural changes of the cardiomyocytes, myocardial fibrosis and expression of ET-1 and CTGF protein. In AF group, the patients receiving RFCA were followed up for 6 months following the procedure for assessment of the outcomes. Compared with the control patients, the patients with AF showed obvious damages of the cardiomyocyte structure and myocardial fibrosis. Serum levels of ET-1 and CTGF levels were significantly higher in PaAF and PeAF groups than in the control group, and were higher in PeAF group than in PaAF group. In the patients with AF, serum ET-1 and CTGF levels were positively correlated with left atrial diameter (LAD) (P < 0.05), and ET-1 was positively correlated with CTGF levels (P < 0.05). In patients with postoperative AF recurrence, the serum levels of ET-1 and CTGF were significantly higher than those in patients without recurrence; serum ET-1 and CTGF levels before and after the operation were positively correlated with the recurrence of PeAF, and elevated serum levels of ET- 1 and CTGF were identified by logistic regression analysis as independent risk factors for postoperative recurrence of PeAF. Serum levels of ET-1 and CTGF are significantly elevated in AF patients in positive correlation with AF duration. ET-1 and CTGF levels are higher in AF patients with postoperative recurrence, and they both have predictive value for recurrence of PeAF following RFCA.

Serum Connective Tissue Growth Factor in Children with Pulmonary Arterial Hypertension Associated with Congenital Heart Disease: Review Article

Serum Connective Tissue Growth Factor in Children with Pulmonary Arterial Hypertension Associated with Congenital Heart Disease: Review Article

Elevated Serum IGFBP-2 and CTGF Levels Are Associated with Disease Activity in Patients with Dermatomyositis.

Background Insulin-like growth factor-binding proteins (IGFBPs) and connective tissue growth factor (CTGF) participate in angiogenesis. Dermatomyositis (DM) is characterized by microvasculopathy-derived skin lesions. Here, we investigated the clinical significance of serum IGFBP and CTGF levels in DM patients. Methods In this study, 65 DM patients and 30 healthy controls were enrolled. Serum IGFBP and CTGF levels were examined by ELISA, and their correlation with clinical and laboratory findings was analyzed by Spearman's correlation. Results Serum IGFBP-2, IGFBP-4, and CTGF levels were higher in DM patients than in healthy controls (median (quartile): 258.9 (176.4–326.1) ng/mL vs. 167.7 (116.1–209.4) ng/mL, p < 0.0001; 450.4 (327.3–631.8) ng/mL vs. 392.2 (339.0–480.2) ng/mL, p = 0.04; and 45.71 (38.54–57.45) ng/mL vs. 35.52 (30.23–41.52) ng/mL, p = 0.001, respectively). IGFBP-2 and CTGF levels were positively correlated with cutaneous (r = 0.257, p = 0.040 and r = 0.427, p = 0.015, respectively) and global (r = 0.380, p = 0.002 and r = 0.292, p = 0.019, respectively) disease activity in DM patients. Conclusion Serum IGFBP-2 and CTGF levels were increased in patients with DM and correlated with cutaneous and global disease activity.

Role of transforming growth factor-beta 1 and connective tissue growth factor levels in coronavirus disease-2019-related lung Injury: a prospective, observational, cohort study.

ABSTRACTBackground: Coronavirus disease-2019 (COVID-19) results in acute lung injury. This study examined the usefulness of serum transforming growth factor-beta 1 (TGF-β1) and connective tissue growth factor (CTGF) levels in predicting disease severity in COVID-19 patients with pulmonary involvement.Methods: Fifty patients with confirmed COVID-19 and pulmonary involvement between September 2020, and February 2021 (Group 1) and 45 healthy controls (Group 2) were classified into three subgroups based on clinical severity: moderate, severe, and critical pneumonia. Serum TGF-β1 and CTGF concentrations were measured on days 1 and 7 of admission in Group 1 using an enzyme-linked immunosorbent assay. These concentrations were also measured in control cases. The mean serum TGF-β1 and CTGF levels were then compared among COVID-19 patients, based on clinical severity.Results: Significantly higher mean serum TGF-β1 and CTGF levels were observed on both days in Group 1 than in the control group. The mean serum TGF-β1 and CTGF levels on day 7 were also significantly higher than those on day 1 in Group 1. The critical patient group had the highest serum TGF-β1 and CTGF levels on both days, and the difference between this group and the moderate and severe pneumonia groups was significant. Cutoff values of 5.36 ng/mL for TGF-β1 and 626.2 pg/mL for CTGF emerged as predictors of COVID-19 with pulmonary involvement in receiver-operating characteristic curve analysis. Conclusions: TGF-β1 and CTGF are potential markers that can distinguish COVID-19 patients with pulmonary involvement and indicate disease severity. These findings may be useful for initiating treatment for early-stage COVID-19.

High carbohydrate high fat diet causes arterial hypertension and histological changes in the aortic wall in aged rats: The involvement of connective tissue growth factors and fibronectin

BackgroundAge and diabetes are risk factors for arterial hypertension. However, the relationship between age, connective tissue growth factors, vascular aging and arterial hypertension while on a the high-carbohydrate high-fat diet (HCHFD) remains poorly understood. PurposeTo estimate the relationship between humoral factors, the morphological changes of aorta and impaired blood pressure regulation under the influence of age and a HCHFD. MethodsA study was carried out in male Wistar rats, which were divided into the following groups: 1st (n = 15) - naive young rats; 2nd (n = 15) – young rats, exposed to HCHFD; 3rd (n = 14) – naive old rats; 4th (n = 12) - old rats exposed to HCHFD. The age of old rats was 540 days, and young rats 150 days at the end of the diet. HCHFD contained proteins 16%, fats 21%, carbohydrates 46%, including 17% fructose, 0.125% cholesterol, 90 days. Blood pressure and body weight were measured weekly, carbohydrate metabolism, histological signs of changes in the aorta, serum transforming growth factor-β (TGF-β), connective tissue growth factor (CTGF), fibronectin, and endothelin-1 levels were determined one week after the onset of diet. ResultsThe severity of arterial hypertension and its histological signs in the aortic wall was found to be most pronounced in elderly rats kept on a HCHFD. In young rats kept on a HCHFD, arterial hypertension was transient. An increase in systolic blood pressure has a positive correlation with the degree of obesity, serum fibronectin, and endothelin-1 content, and impaired carbohydrate metabolism. The rise in diastolic blood pressure has a positive correlation with the serum CTGF, endothelin-1, fibronectin levels and aortic wall thickness, and impaired carbohydrate metabolism. A rise in the serum concentration of fibronectin was also associated with increased endothelin-1, TGFβ and CTGF serum levels. ConclusionThis study indicated that an increase in blood pressure in old rats with a high-carbohydrate high-fat diet is due to a disturbance of a structure of the vascular wall, the release of fibronectin, which can occur under the influence of carbohydrate metabolism disorders, endothelin-1, TGFβ and CTGF.

Full composition granules of Huanglian (Rhizoma Coptidis) decrease the serum monocyte chemotactic protein-1 and connective tissue growth factor levels and inhibit kidney nuclear factor-κB expression in rats with high-fat diet-induced diabete.

To investigate the efficacy of the full composition granules of Huanglian (Rhizoma Coptidis) (FGC) on the serum monocyte chemotactic protein-1 (MCP-1) and connective tissue growth factor (CTGF) levels and kidney nuclear factor-κB (NF-κB) expression in rats with high-fat diet-induced diabetes. Diabetes was induced in rats by feeding a high-fat chow combined with intravenous streptozotocin injection. Forty diabetic Sprague- Dawley rats were randomly assigned to a normal group (NG), model group (MG), irbesartan group (IG), and low-, middle-, and high-dosage FGC groups (LFGC, MFGC, HFGC), with eight rats per group. The IG rats received 31.25 mg·kg－1·d－1 irbesartan tablets, whereas those in the LFGC, MFGC, and HFGC were administered 52, 312.5, and 625 mg·kg－1·d－1 FGC, respectively. After 12 weeks, bodyweight (BW), left kidney weight (KW), hemoglobin A1c (HbA1c), serum creatinine (Scre), blood urea nitrogen (BUN), and serum MCP-1 and CTGF levels were determined, pathological changes of the kidney were recorded, and kidney NF-κB p65 (A) expression was measured. The 24-h urine albumin and levels of HbA1c, Scre, BUN, and serum MCP-1 and CTGF were significantly increased in in the MG compared with the NG, as was the kidney NF-κB (p65) expression (P < 0.05). Furthermore, clear pathological changes in kidney fibrosis were observed in the MG rats. Following irbesartan and FGC administration, the 24-h urine albumin and the levels of HbA1c, Scre, and serum MCP-1 and CTGF were significantly decreased in FCG groups compared with those in the MG, which is in agreement with the change in the kidney NF-κB (p65) expression, whereas the similarly significant decrease only exist in 24-h urine albumin and the levels of serum CTGF after irbesartan administration. Hematoxylin-eosin (HE) staining results indicated that the fibrosis observed in the MG samples was alleviated through FGC treatment. FGC may alleviate potential kidney injury by decreasing the serum MCP-1 and CTGF levels and inhibiting NF-kB expression in diabetic nephropathy in rats with high-fat diet-induced diabetes.

Response to the letter entitled “Diagnostic value of serum connective tissue growth factor in rheumatoid arthritis: Methodological Issues” by Ghjari et al.

Response to the letter entitled “Diagnostic value of serum connective tissue growth factor in rheumatoid arthritis: Methodological Issues” by Ghjari et al.

Diagnostic value of serum connective tissue growth factor in rheumatoid arthritis.

Serum connective tissue growth factor (CTGF) is reported to be a potential biomarker for the diagnosis of rheumatoid arthritis (RA). Our study aimed to investigate the prevalence of serum CTGF and the association with the clinical features in RA patients. Serum samples were obtained from 180 patients with RA, 168 patients with other rheumatic diseases, including 43 systemic lupus erythematosus (SLE), 34 osteoarthritis (OA), 17 primary Sjögren's syndrome (pSS), 20 ankylosing spondylitis (AS), 23 psoriatic arthritis (PsA), 6 reactive arthritis (ReA), 20 systemic sclerosis (SSc), and 5 systemic vasculitis (SV), and 64 healthy individuals. The clinical and laboratory data of patients with RA were collected. Levels of CTGF in serum were measured by enzyme linked immunosorbent assay (ELISA). Associations between CTGF and the clinical features of RA were analyzed. The positivity of serum CTGF among RA patients (33.89%) was significantly higher than those of SLE (9.3%), OA (0%), AS (0%), pSS (0%), PsA (0%), ReA (0%), SSc (5%), SV (0%), and healthy controls (4.69%) (p< 0.0001). The mean concentration of serum CTGF in RA was also significantly higher than those in other rheumatic diseases and healthy controls (p< 0.001). At the cut-off value of 263.30pg/ml, the sensitivity, specificity, positive predictive value, and negative predictive value of serum CTGF for RA were 33.89%, 96.55%, 88.41%, and 55.45%, respectively. Anti-cyclic citrullinated peptide (anti-CCP) antibody (p< 0.001), rheumatoid factor (RF) (p < 0.001), IgG (p= 0.025), and IgM (p= 0.004) in CTGF-positive patients were higher than those in CTGF-negative patients. Besides, the positive rate of serum CTGF was significantly higher in RA patients with interstitial lung disease (ILD) (53.1%, 26/49) than RA-non-ILD patients (26.7%, 35/131, p= 0.003). Serum CTGF, as a novel biomarker, has certain diagnostic value for RA. Further studies are necessary to get more knowledge for the diagnostic performance of CTGF in RA. KEY POINTS: • Serum CTGF, as a novel biomarker, has certain diagnostic value for RA, the sensitivity, specificity, positive predictive value, and negative predictive value of which were 33.89%, 96.55%, 88.41%, and 55.45%, respectively. • Serum CTGF was more common to be positive in RA-ILD patients (53.1%, 26/49) than RA-non-ILD patients (26.7%, 35/131, p= 0.003).

VALUE OF CTGF IN ASSESSMENT OF LIVER GRAFT WITH NON-ALCOHOLIC FATTY LIVER DISEASE AFTER BRAIN DEATH

Background and Purpose: As the prevalence of nonalcoholic fatty liver disease (NAFLD) is increasing globally, an accurate evaluation of liver steatosis in potential donors is required for liver transplantation. Connective tissue growth factor (CTGF) plays an important role in the acute hepatic inflammation, chronic liver injury and liver fibrosis. In this study, intrahepatic and systemic CTGF expressions were measured from brain-dead donors (BDDs) with NAFLD, and evaluated as biomarker of NAFLD-induced graft injury. Methods: Liver and blood samples were obtained from brain-dead organ donors and patients with angiomas for RNA-sequencing and validation by RT-PCR, WB and IHC. The NAFLD rat model was established by feeding rats with the high fat diet, and thereafter brain death was developed by increasing intracranial pressure in healthy or NAFLD rats. The samples from NAFLD rats, brain-dead rats and the controls were used for further detection and analysis. Systemic CTGF levels from human and rats were measured by ELISA and analyzed the relation with the quantitative histopathological score in livers from NAFLD donors. Results: Through transcriptome analysis, CTGF was down-regulated in the healthy liver from BDDs with the fold change of 0.34 (P<0.05), which was further verified in the healthy livers from humans and rats by RT-PCR, WB and IHC (P<0.05). In parallel, CTGF protein was highly overexpressed in the fatty liver compared with the healthy liver after brain death by IHC (P<0.05). The correlation analysis indicated a linear correlation between serum levels and intrahepatic expression of CTGF in both humans and rats (P<0.05). CTGF concentration correlated with the severity of NAFLD-induced liver injury. Conclusion: After brain death, CTGF was down-regulated in the healthy liver and still over-expressed in the fatty liver from donor with NAFLD. Serum CTGF level from BDDs might be a predictor of steatosis severity for graft evaluation.

Correlation analysis between mechanical power, transforming growth factor-β1, and connective tissue growth factor levels in acute respiratory distress syndrome patients and their clinical significance in pulmonary structural remodeling.

Background:To identify the clinical correlations between mechanical power and transforming growth factor-β1 (TGF-β1) and connective tissue growth factor (CTGF) in acute respiratory distress syndrome (ARDS) patients, their clinical significance in pulmonary structural remodeling in ARDS patients was investigated.Methods:Ninety-five patients with moderate or severe ARDS, who required mechanical ventilation therapy, were randomly selected among hospitalized patients from January 2017 to February 2019. Their mechanical power was monitored and recorded, the TGF-β1 and CTGF levels were detected by enzyme-linked immunosorbent assay (ELISA), their relevance was analyzed, and the relationship between mechanical power and 28-day survival rate was investigated. According to the high-resolution computed tomography (HRCT) examination, the patients were divided into an ARDS group and an ARDS pulmonary fibrosis (ARDS-PF) group. The differences in mechanical power, TGF-β1, and CTGF between the 2 groups were compared, and the significance of TGF-β1 and CTGF in the diagnosis of ARDS pulmonary interstitial fibrosis were evaluated.Results:A significant positive correlation between mechanical power and serum TGF-β1 and CTGF in patients with ARDS was found and the correlation coefficients were 0.424 and 0.581, respectively. The difference between mechanical power and 28-day survival rate was statistically significant (P < .05), while the area under the receiver operating characteristic curves of TGF-β1 and CTGF for the diagnosis of ARDS pulmonary fibrosis was 0.838 and 0.884, respectively (P < .05).Conclusion:A significant correlation between mechanical power and serum fibrosis biomarkers TGF-β1 and CTGF in ARDS patients was found, and its level was related to the survival prognosis of patients. Mechanical power, TGF-β1, and CTGF were clinically evaluated for the assessment of lung structural remodeling, such as ARDS pulmonary fibrosis. This study has particular significance to the early prevention of ventilator-induced lung injury and pulmonary fibrosis in patients with ARDS receiving mechanical ventilation.

Serum connective tissue growth factor is a highly discriminatory biomarker for the diagnosis of rheumatoid arthritis

BackgroundOur previous proteomic study indicated that connective tissue growth factor (CTGF) may be a potential biomarker for rheumatoid arthritis (RA) diagnosis. The aim was to assess the performance of CTGF as a biomarker of RA.MethodSerum and synovial fluid CTGF was detected using a direct high sensitivity sandwich ELISA kit. Serum CTGF levels were tested for discriminatory capacity and optimal assay cutoffs determined in a training cohort of 98 cases of RA with 103 healthy controls. The assay performance was then validated in a further cohort of 572 patients (with RA (n = 217), ankylosing spondylitis (n = 92), gout (n = 74), osteoarthritis (n = 52), systemic lupus erythematosus (n = 72), or primary Sjögren’s syndrome (pSS) (n = 65)).ResultsSignificant elevation of synovial fluid CTGF concentration was found in RA patients, demonstrating excellent diagnostic ability to predict RA (area under the curve (AUC) = 0.97). Similar results were found in serum CTGF detection. At the optimal cutoff value 88.66 pg/mL, the sensitivity, specificity, and the AUC was 0.86, 0.92, and 0.92, respectively, in the training cohort. Similar performance was observed in the validation cohort, with sensitivity, specificity, positive likelihood, and negative likelihood of 0.82, 0.91, 5.74, and 0.12, respectively. Stronger discriminatory capacity was seen with the combination of CTGF and anti-citrullinated protein antibody (ACPA) (AUC = 0.96) than with either ACPA or rheumatoid factor (RF) alone (AUC = 0.80 or 0.79, respectively). The discriminatory performance of serum CTGF was consistent across all inflammatory conditions tested (AUC >0.92 in all cases), with the sole exception of pSS. Serum CTGF did not vary with symptom duration or disease activity.ConclusionsSerum CTGF is a promising diagnostic biomarker for RA, with performance in the current study better than either ACPA or RF.

Connective tissue growth factor is activated by gastrin and involved in gastrin-induced migration and invasion

Connective tissue growth factor (CTGF) has been reported in gastric adenocarcinoma and in carcinoid tumors. The aim of this study was to explore a possible link between CTGF and gastrin in gastric epithelial cells and to study the role of CTGF in gastrin induced migration and invasion of AGS-GR cells. The effects of gastrin were studied using RT-qPCR, Western blot and assays for migration and invasion. We report an association between serum gastrin concentrations and CTGF abundancy in the gastric corpus mucosa of hypergastrinemic subjects and mice. We found a higher expression of CTGF in gastric mucosa tissue adjacent to tumor compared to normal control tissue. We showed that gastrin induced expression of CTGF in gastric epithelial AGS-GR cells via MEK, PKC and PKB/AKT pathways. CTGF inhibited gastrin induced migration and invasion of AGS-GR cells. We conclude that CTGF expression is stimulated by gastrin and involved in remodeling of the gastric epithelium.

Correlation btween IgG4, TGF-β1, CTGF and fibrosis in Hashimoto thyroiditis

Objective To explore the correlation among serum immunoglobulin G4 (IgG4), transforming growth factor-β1 (TGF-β1), connective tissue growth factor (CTGF) and Hashimoto thyroiditis(HT) thyroid fibrosis. Methods Case-control study. A total of 159 patients with HT visiting the Wuhan Union Hospital were collected from May 2013 to March 2015. All patients were divided into IgG4 HT group (IgG4≥1.35 g/L, n=39) and non-IgG4 HT group (IgG4<1.35 g/L, n=120). The serum IgG4, TGF-β1 and CTGF were determined by enzyme-linked immunosorbent assays. The levels of serum thyroid peroxidase antibodies (TPOAb) and thyroglobulin antibodies (TgAb) were measured by electrochemiluminescence immunoassay. Meanwhile, ultrasound of the thyroid gland was performed. Statistical analysis was performed by use of SPSS 17.0 software. The Mann-Whitney U test was used to compare two independent samples of non-normal distribution data, Fisher′s exact test was employed to analyze thyroid imaging differences, correlation test was performed to examine various correlations, multivariate Logistic regression analysis was used to evaluate thyroid fibrosis risk factors. Results Compared with that of non-IgG4 HT group, IgG4 HT group: TPOAb [(455.2±169.7) vs. (186.5±102.3), U=27.0, P=0.003], TgAb [(984.6±452.7) vs. (289.3±245.1), U=30.5, P=0.017], TGF-β1 [(1.45±0.97) vs. (0.30±0.22), U=119.0, P=0.035] and CTGF [(88.65±14.39) vs. (62.21±8.76), U=69.0, P=0.039] were significantly higher, thyroid ultrasound showed obvious fibrosis (35/4 vs. 32/88, χ2=48.03, P=0.000); significant positive linear correlation between IgG4 and TPOAb (r=0.719, P=0.000), CTGF and TGF-β1 (r=0.500, P<0.01) respectively. Logistic regression analysis indicated that all the serum IgG4, TPOAb, TGF-β1 and CTGF were independent risk factors of thyroid fibrosis [IgG4, odds ratio (OR)=1.968, P=0.014, 95%confidence interval (CI)=1.287-2.041; TPOAb, OR=2.537, P=0.012, CI=1.322-2.869; TGF-β1, OR=1.549, P=0.023, CI=1.105-1.498; CTGF, OR=1.185, P=0.046, CI=1.204-1.625]. Conclusion The highlevel of circulating antibodies, IgG4, TGF-β1 and CTGF were significantly associated with thyroid fibrosis, and were independent risk factors of HT fibrosis.(Chin J Lab Med, 2015, 38: 848-851) Key words: Hashimoto disease; Fibrosis; Immunoglobulin G; Transforming growth factor beta1; Connective tissue growth factor

Expression of connective tissue growth factor in the serum of children with congenital heart disease combined with pulmonary hypertension

Objective To further study the pathogenesis for congenital heart disease(CHD) and connective tissue growth factor(CTGF) for the early diagnosis of CHD and pulmonary hypertension(PH). Methods Sixty-six cases of children with CHD were selected from the thoracic surgery who were performed in the Children's Hospital of Shanxi Province during the period between Sep.2012 and Jan.2013.Based on the cardiac color Doppler estimation of the pulmonary artery systolic pressure, they were classified into several groups: unincorporated PH group with 16 cases, mild PH group with 18 cases, moderate PH group with 17 cases, and severe PH group with 15 cases.Based on types, the 66 cases could be classified as ventricular septal defect(VSD) group with 23 cases, atrial septal defect(ASD) group with 17 cases, patent ductus arteriosus(PDA) group with 14 cases, and composite(including 2 or more of the congenital cardiovascular anomalies) group with 12 cases.Twenty healthy children who had medical examination over the same period in the Children's Hospital of Shanxi Province were randomly chosen as the healthy control group.The serum concentration of CTGF in the research objects were determined with the aid of double antibody sandwich enzyme-linked immunosorbent assay method.According to the different pulmonary artery systolic pressure and different types of CHD, the serum concentration of CTGF were compared among groups.The correlation of between the CTGF concentration in the serum and pulmonary artery systolic pressure were also analyzed among the groups of children with CHD. Results Quantitative measurement revealed that the serum CTGF concentration measured in the groups of children with CHD were significantly higher than that in the healthy control group(P<0.05); the serum CTGF concentration of the children with CHD and PH was higher than that in the group of children with CHD alone(P<0.05). With the increase in pulmonary artery pressure, CHD patients serum levels of CTGF also increased(P<0.05). By the correlation analysis, the results showed that the serum level of CTGF in the CHD groups were positively correlated with the pulmonary artery pressure(r=0.670, P=0.005; r=0.514.P=0.029; r=0.517, P=0.034; r=0.707, P=0.003). The difference in terms of serum CTGF concentration in different types of CHD patients was not significant(F=0.270, P=0.847). Conclusions There exists certain damage in CHD early myocardial fibrosis(unincorporated PH), when combined with PH, myocardial fibrosis increases with the gradual increase of pulmonary artery pressure.However, the degree of myocardial fibrosis shows no correlation with the type of CHD. Key words: Congenital heart disease; Pulmonary hypertension; Connective tissue growth factor

Effect of alprostadil combined with Diammonium glycyrrhizinate on renal interstitial fibrosis in SD rats.

To observe effect of alprostadil combined with Diammonium glycyrrhizinate on renal interstitial fibrosis in SD rats. A total of 75 SD rats were randomly divided into A, B, C, D, E groups with 15 in each group. Rats in group A served as the control group received just only but tissue separation without modeling operation, while model of unilateral ureteral obstruction (UUO) was established in B, C, D, E groups. Rats in A, B group were given saline lavage placebo treatment, while rats in C, D, E groups were given diammonium glycyrrhizinate and alprostadil injection. Five rats were sacrificed 1, 2, 3 weeks after modeling, serum creatinine level of femoral venous blood was determined. Transforming growth factor - β1 (TGF - β1) and concentration of connective tissue growth factor (CTGF) were also detected by using ELISA. Line renal interstitial tissue was taken after HE staining, renal interstitial TGF - β1 and CTGF expression were detected by using immunohistochemical method. Serum creatinine levels of B, C, D, E group at different time points in were significantly higher than that of group A (P<0.05); serum creatinine levels in group B were significantly higher than that of C, D, E group at each time point (P<0.05). Serum creatinine level of Group E was significantly lower than C, D group after 2, 3 weeks (P<0.05). Rats in A group at each time point showed no significant changes in TGF - β1 and CREA concentration in serum and kidney tissues (P>0.05); while serum and kidney tissue TGF - β1, concentration of CREA, expression of rats in B, C, D, E groups showed a gradual increasing trend over time. TGF - β1 and CREF of Group B in serum and kidney tissues at each time point were significantly higher than that of the other groups (P<0.05). TGF - β1 and CREF of Group E in serum and kidney tissues at each time point were significantly lower than that of B, C, D group at all time points in serum and kidney tissues (P<0.05). Alprostadil combined with diammonium glycyrrhizinate can significantly lower the expression of TGF - β1 and CTGF in serum and tissues of SD rat with renal interstitial fibrosis, thus inhibit rat renal interstitial fibrosis process. It has synergy protective effect.

Correlation of CTGF gene promoter methylation with CTGF expression in type 2 diabetes mellitus with or without nephropathy

Increasing evidence shows that DNA methylation is involved in the development and progression of diabetes mellitus (DM) and its complications. Previous studies conducted by our group have indicated that high glucose levels may induce the demethylation process of the connective tissue growth factor (CTGF) gene promoter and increase the expression of CTGF in human glomerular mesangial cells. Based on these findings, the aim of the present study was to investigate the methylation level of genomic DNA and the CTGF promoter in patients with type 2 DM and to analyze its possible correlation with CTGF expression. Methylation levels of the whole genomic DNA were detected by high-performance liquid chromatography in a non-diabetes control (NDM) group (n=29), a diabetes without nephropathy (NDN) group (n=37) and a diabetes with nephropathy (DN) group (n=38). CTGF promoter methylation levels were detected by methylation-specific polymerase chain reaction and bisulfite sequencing. The levels of serum CTGF were assessed using the enzyme-linked immunosorbent assay. The methylation levels of the whole genomic DNA were not significantly different among the three groups. However, the CTGF methylation levels in the two diabetes groups were significantly lower than those in the NDM group (P<0.05), with the lowest methylation level in the DN group (P<0.05). The CTGF protein levels in the DN group were significantly higher than those in the NDM and NDN groups (P<0.05). Levels of CTGF were negatively correlated with the estimated glomerular filtration rate (eGFR) and the methylation level of the promoter, while they were positively correlated with age, urinary albumin-to-creatinine ratio (UACR), blood urea nitrogen, creatinine, fasting blood sugar and postprandial blood glucose. Multiple stepwise regression analysis showed that CTGF expression was associated with the UACR, CTGF methylation level and eGFR. DNA methylation is a regulatory mechanism of CTGF expression, which is decreased in patients with DM, particularly in those with DN, and may contribute to the pathogenesis of nephropathy.

The serum levels of connective tissue growth factor in patients with systemic lupus erythematosus and lupus nephritis

The expression of connective tissue growth factor mRNA in human kidneys may serve as an early marker for lupus nephritis progression. Therefore, we speculated that connective tissue growth factor may be involved in the pathogenesis of systemic lupus erythematosus and lupus nephritis. In this study, we set out to investigate the associations between serum connective tissue growth factor levels and clinicopathological features of patients with systemic lupus erythematosus and lupus nephritis. Serum samples from patients with non-renal systemic lupus erythematosus, renal biopsy-proven lupus nephritis and healthy control subjects were detected by enzyme-linked immunosorbent assay for serum connective tissue growth factor levels. The associations between connective tissue growth factor levels and clinicopathological features of the patients were further analysed. The levels of serum connective tissue growth factor in patients with non-renal systemic lupus erythematosus and lupus nephritis were both significantly higher than those in the normal control group (34.14 ± 12.17 ng/ml vs. 22.8 ± 3.0 ng/ml, p<0.001; 44.1 ± 46.8 ng/ml vs. 22.8 ± 3.0 ng/ml, p = 0.035, respectively). There was no significant difference of the serum connective tissue growth factor levels between non-renal systemic lupus erythematosus and lupus nephritis group (34.14 ± 12.17 ng/ml vs. 44.1 ± 46.8 ng/ml, p = 0.183). Serum connective tissue growth factor levels were significantly higher in lupus nephritis patients with the following clinical manifestations, including anaemia (51.3 ± 51.4 ng/ml vs. 23.4 ± 9.7 ng/ml, p<0.001) and acute renal failure (85.5 ± 75.0 ng/ml vs. 31.2 ± 21.8 ng/ml, p = 0.002). Serum connective tissue growth factor levels in class IV were significantly higher than that in class II, III and V (57.6 ± 57.5 ng/ml vs. 18.7 ± 6.4 ng/ml, p = 0.019; 57.6 ± 57.5 ng/ml vs. 25.2 ± 14.9 ng/ml, p = 0.006; 57.6 ± 57.5 ng/ml vs. 30.5 ± 21.3 ng/ml, p = 0.017, respectively). Serum connective tissue growth factor levels were significantly higher in those with both active/chronic lesions than those in those with active lesions only in either class IV (84.9 ± 69.6 ng/ml vs. 40.0 ± 40.2 ng/ml, p = 0.001) or in combination of class III and IV lupus nephritis (63.3 ± 63.4 ng/ml vs. 38.3 ± 37.9 ng/ml, p = 0.035, respectively). Serum connective tissue growth factor levels were negatively associated with estimated glomerular filtration rate (r = -0.46, p<0.001) and positively associated with interstitial inflammation (r = 0.309, p = 0.002) and interstitial fibrosis (r = 0.287, p = 0.004). Serum connective tissue growth factor level was a risk factor for doubling of serum creatinine in lupus nephritis (p<0.001, hazard ratio = 1.015, 95% confidence intervals 1.008-1.022) in univariate analysis. Serum connective tissue growth factor levels were significantly higher in lupus and correlated with chronic renal interstitial injury and doubling of serum creatinine in patients with lupus nephritis.

Connective Tissue Growth Factor: A Predictor of Recurrence after Catheter Ablation in Patients with Nonparoxysmal Atrial Fibrillation

Although catheter ablation can effectively eliminate atrial fibrillation (AF), the progression of atrial remodeling increases the risk of recurrence. We, therefore, examined the possibility of determining the postablation prognosis of patients with AF using biomarkers of atrial structural remodeling and serum connective tissue growth factor (CTGF) level, and measured its changes after catheter ablation. Subjects were 400 consecutive patients (308 with paroxysmal AF and 92 with nonparoxysmal AF [persistent and long-standing persistent AF]) who underwent catheter ablation for drug-resistant AF. Serum CTGF levels were measured before and 2 months after ablation. During the follow-up period of 20.5 ± 6.9 (8-30) months, 61 patients (66%) with nonparoxysmal AF and 95 patients (31%) with paroxysmal AF had recurrence after catheter ablation. Recurrence was associated with higher "baseline CTGF level" in patients with nonparoxysmal AF (936.5 ± 93.1 ng/mL vs 746.3 ± 56.9 ng/mL, P = 0.007) instead of patients with paroxysmal AF (851.6 ± 97.6 ng/mL vs 807.6 ± 99.1 ng/mL, P = 0.921). In nonparoxysmal AF, the recurrence subgroup also had larger left atrial diameter (LAD; 47.1 ± 5.2 mm vs 39.5 ± 4.3 mm, P = 0.035) compared with the nonrecurrence subgroup, and "baseline serum CTGF" and LAD were shown to be independent predictors for postablation recurrence by a Cox proportional hazards model. However, the 2-month postablation elevations of CTGF in patients with recurrence were not significantly different from that in patients without recurrence in nonparoxysmal AF. Our finding indicates that "baseline serum CTGF level" is an independent predictor for recurrence in patients with nonparoxysmal AF following catheter ablation. Two-month postablation elevation in CTGF has no association with recurrence.

Serum Biomarkers as Predictors of Stage of Work-related Musculoskeletal Disorders

Musculoskeletal disorders (MSDs) are a leading worldwide cause of long-term pain and physical disability,1 with diagnoses including tendinopathies, nerve compression syndromes, and muscular and joint disorders.2,3 Studies in people with upper extremity work-related MSDs (WMSDs) find evidence of inflammation, fibrosis, and degeneration in serum and musculotendinous tissues, although the timing of each is unknown.4-7 Serum biomarkers that might aid in pinpointing the stage of these disorders are being investigated. Several risk factors have been identified, including forceful exertions, repetitive motion, and nonneutral body postures. A recent systematic review showed a consistent pattern of force-repetition interaction for musculoskeletal disorder risk, with low-force repetitive tasks demonstrating a modest increase in MSD risk, whereas high-force repetitive tasks result in rapid escalation in MSD risk, which is indicative of tissue fatigue failure.8 We have developed a rat model of voluntary reaching and handlepulling for food reward,9 in which reach rates and force levels were determined from epidemiologic studies. One goal of our laboratory is to identify biomarkers for monitoring disease progression of WMSDs and appropriate targeting of treatments. We recently examined whether serum inflammatory cytokines exhibit force × repetition interaction responses using this rat model.10 Serum tumor necrosis factor-α (TNF-α) shows a significant force × repetition interaction (P = 0.0003) with task performance (Figure 1, A). No increases in TNF-α were seen in low-force groups, but high increases were observed in rats performing high-repetition, high-force tasks.11-13 These results indicate that serum TNF-α follows the fatigue-failure theory during acute phases of ≤3 months. TNF-α and related cytokines may provide the best gauge of overall acute tissue damage resulting from repetitive, forceful exertions and may be the best biomarkers of this phase of WMSDs.Figure 1: Graph of serum biomarkers in a rat model of upper extremity work-related musculoskeletal disorders. A, Serum levels of tumor necrosis factor (TNF)-α in rats performing one of four tasks for 12 weeks. B, Schematic illustration showing temporal changes in serum levels of TNF-α and interleukin-10 (IL-10) (left axis) and connective tissue growth factor (CTGF) (right axis) in rats performing high-repetition, low-force (HRLF) tasks for 24 weeks. HRHF = high-repetition, high-force; LRHF = low-repetition, high-force; LRLF = low-repetition, low-forceThe timing of the inflammatory versus fibrotic responses with WMSDs is also of clinical interest. Studies have detected serum biomarkers of inflammation in patients with upper extremity WMSDs of short duration (≤3 months), including TNF-α,4-6 again suggesting a role for inflammatory cytokines early in the course of upper extremity WMSDs. However, studies examining tissues from patients with upper extremity WMSDs during surgical intervention show increased tissue fibrogenic proteins and fibrotic histopathology, which is indicative of deranged extracellular matrix production and degeneration in tissues by this time point.7 Therefore, we extended our rat studies to examine the effects of performing a high-repetition, low-force task for 24 weeks. Serum TNF-α levels increased early after training but declined by week 18 (Figure 1, B). In contrast, serum interleukin-10 (IL-10), an anti-inflammatory cytokine, increased steadily until week 18. This may be one reason for the decreasing TNF-α because IL-10 plays a key role in limiting immune responses. We next examined serum for connective tissue growth factor (CTGF), an important mediator of fibrosis. Studies have shown that CTGF increases in tissues under conditions of overload or injury and that it is a key player in the pathogenesis of fibrosis.14 We observed increased serum and tissue CTGF by week 24, compared with controls (P = 0.03) (Figure 1, B). It is known that transforming growth factor-β1 induces CTGF expression, leading to fibroblast proliferation and collagen deposition.14 However, CTGF production is also regulated by TNF-α,15 which is an interesting fact considering their temporal relationship (Figure 1, B). Importantly, because the CTGF level is normally low in sera of healthy individuals, it may serve as a predictive biomarker for patients in the fibrotic stage of WMSDs. Our results indicate that most serum inflammatory cytokines, including TNF-α, demonstrate force-repetition interactions. These findings support the use of key pro-inflammatory cytokines as biomarkers of acute tissue damage and the fatigue failure hypothesis as a mechanism underlying WMSDs. We have also observed significantly increased serum and tissue CTGF levels that correlated with tissue fibrosis. Additional studies are underway to determine whether elevated CTGF is an essential mediator of fibrotic events. If so, one could envision CTGF as a potential therapeutic target to prevent fibrosis and reduced function and as a serum biomarker of tissue fibrogenic changes occurring with WMSDs.