Metformin inhibits aldosterone-induced cardiac fibroblast activation, migration and proliferation in vitro, and reverses aldosterone+salt-induced cardiac fibrosis in vivo

2016 ◽  
Vol 98 ◽  
pp. 95-102 ◽  
Author(s):  
Srinivas Mummidi ◽  
Nitin A. Das ◽  
Andrea J. Carpenter ◽  
Hemanthkumar Kandikattu ◽  
Maike Krenz ◽  
...  
eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Qiankun Bao ◽  
Bangying Zhang ◽  
Ya Suo ◽  
Chen Liu ◽  
Qian Yang ◽  
...  

Intermittent hypoxia (IH) is the predominant pathophysiological disturbance in obstructive sleep apnea (OSA), known to be independently associated with cardiovascular diseases. However, the effect of IH on cardiac fibrosis and molecular events involved in this process are unclear. Here, we tested IH in angiotensin II (Ang II)-induced cardiac fibrosis and signaling linked to fibroblast activation. IH triggered cardiac fibrosis and aggravated Ang II-induced cardiac dysfunction in mice. Plasma thrombospondin-1 (TSP1) content was upregulated in both IH-exposed mice and OSA patients. Moreover, both in vivo and in vitro results showed IH-induced cardiac fibroblast activation and increased TSP1 expression in cardiac fibroblasts. Mechanistically, phosphorylation of STAT3 at Tyr705 mediated the IH-induced TSP1 expression and fibroblast activation. Finally, STAT3 inhibitor S3I-201 or AAV9 carrying a periostin promoter driving the expression of shRNA targeting Stat3 significantly attenuated the synergistic effects of IH and Ang II on cardiac fibrosis in mice. This work suggests a potential therapeutic strategy for OSA-related fibrotic heart disease.


2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Masataka Nishiga ◽  
Takahiro Horie ◽  
Yasuhide Kuwabara ◽  
Osamu Baba ◽  
Tetsushi Nakao ◽  
...  

Background: A highly conserved microRNA, miR-33 is considered as a potential therapeutic target for atherosclerosis, because recent reports, including ours, indicated miR-33 has atherogenic effects by reducing HDL-C. However, the functions of miR-33 in heart failure remain to be elucidated. Methods and results: To clarify the functions of miR-33 involved in cardiac hypertrophy and fibrosis in vivo, we investigated the responses to pressure overload by transverse aortic constriction (TAC) in miR-33 deficient (KO) mice. When subjected to TAC, miR-33 expression level was significantly up-regulated in wild-type (WT) left ventricles, whereas miR-33 KO hearts displayed no less hypertrophic responses than WT hearts. However, interestingly, histological and gene expression analyses showed ameliorated cardiac fibrosis in miR-33 KO hearts compared to WT hearts. Furthermore, we generated cardiac fibroblast specific miR-33 deficient mice, which also showed ameliorated cardiac fibrosis when they were subjected to TAC. We also found that cardiac fibroblasts were mainly responsible for miR-33 expression in the heart, because its expression was about 4-folds higher in isolated primary cardiac fibroblasts than cardiomyocytes. Deficiency of miR-33 impaired cell proliferation in primary fibroblasts, which was considered due to altered lipid raft cholesterol content by up-regulated ATP-binding cassette transporter A1/G1. Conclusion: Deficiency of miR-33 impaired fibroblast proliferation in vitro, and ameliorated cardiac fibrosis induced by pressure overload in vivo.


2018 ◽  
Vol 19 (10) ◽  
pp. 3207 ◽  
Author(s):  
Fahmida Jahan ◽  
Natalie Landry ◽  
Sunil Rattan ◽  
Ian Dixon ◽  
Jeffrey Wigle

Following cardiac injury, fibroblasts are activated and are termed as myofibroblasts, and these cells are key players in extracellular matrix (ECM) remodeling and fibrosis, itself a primary contributor to heart failure. Nutraceuticals have been shown to blunt cardiac fibrosis in both in-vitro and in-vivo studies. However, nutraceuticals have had conflicting results in clinical trials, and there are no effective therapies currently available to specifically target cardiac fibrosis. We have previously shown that expression of the zinc finger E box-binding homeobox 2 (Zeb2) transcription factor increases as fibroblasts are activated. We now show that Zeb2 plays a critical role in fibroblast activation. Zeb2 overexpression in primary rat cardiac fibroblasts is associated with significantly increased expression of embryonic smooth muscle myosin heavy chain (SMemb), ED-A fibronectin and α-smooth muscle actin (α-SMA). We found that Zeb2 was highly expressed in activated myofibroblast nuclei but not in the nuclei of inactive fibroblasts. Moreover, ectopic Zeb2 expression in myofibroblasts resulted in a significantly less migratory phenotype with elevated contractility, which are characteristics of mature myofibroblasts. Knockdown of Zeb2 with siRNA in primary myofibroblasts did not alter the expression of myofibroblast markers, which may indicate that Zeb2 is functionally redundant with other profibrotic transcription factors. These findings add to our understanding of the contribution of Zeb2 to the mechanisms controlling cardiac fibroblast activation.


2015 ◽  
Vol 309 (8) ◽  
pp. H1346-H1353 ◽  
Author(s):  
K. M. D'Souza ◽  
L. A. Biwer ◽  
L. Madhavpeddi ◽  
P. Ramaiah ◽  
W. Shahid ◽  
...  

Transient angiotensin-converting enzyme (ACE) inhibition induces persistent changes that protect against future nitric oxide synthase (NOS) inhibitor-induced cardiac fibrosis and inflammation. Given the role of fibroblasts in mediating these effects, the present study investigates whether prior ACE inhibition produced persistent changes in cardiac fibroblast physiology. Adult male spontaneously hypertensive rats (SHRs) were treated with vehicle (C+L) or the ACE inhibitor, enalapril (E+L) for 2 wk followed by a 2-wk washout period and a subsequent 7-day challenge with the NOS inhibitor Nω-nitro-l-arginine methyl ester. A third set of untreated SHRs served as controls. At the end of the study period, cardiac fibroblasts were isolated from control, C+L, and E+L left ventricles to assess proliferation rate, collagen expression, and chemokine release in vitro. After 7 days of NOS inhibition, there were areas of myocardial injury but no significant change in collagen deposition in E+L and C+L hearts in vivo. In vitro, cardiac fibroblasts isolated from C+L but not E+L hearts were hyperproliferative, demonstrated increased collagen type I gene expression, and an elevated secretion of the macrophage-recruiting chemokines monocyte chemoattractant protein-1 and granulocyte macrophage-colony stimulating factor. These findings demonstrate that in vivo Nω-nitro-l-arginine methyl ester treatment produces phenotypic changes in fibroblasts that persist in vitro. Moreover, this is the first demonstration that transient ACE inhibition can produce a persistent modification of the cardiac fibroblast phenotype to one that is less inflammatory and fibrogenic. It may be that the cardioprotective effects of ACE inhibition are related in part to beneficial changes in cardiac fibroblast physiology.


2021 ◽  
Vol 8 ◽  
Author(s):  
Zhi-Teng Chen ◽  
Qing-Yuan Gao ◽  
Mao-Xiong Wu ◽  
Meng Wang ◽  
Run-Lu Sun ◽  
...  

Objective: To explore the role of glycolysis in cardiac fibroblast (CF) activation and cardiac fibrosis after myocardial infarction (MI).Method:In vivo: 2-Deoxy-D-glucose (2-DG), a glycolysis inhibitor, was injected into the abdominal cavity of the MI or sham mice every day. On the 28th day, cardiac function was measured by ultrasonic cardiography, and the hearts were harvested. Masson staining and immunofluorescence (IF) were used to evaluate the fibrosis area, and western blot was used to identify the glycolytic level. In vitro, we isolated the CF from the sham, MI and MI with 2-DG treatment mice, and we also activated normal CF with transforming growth factor-β1 (TGF-β1) and block glycolysis with 2-DG. We then detected the glycolytic proteins, fibrotic proteins, and the concentrations of lactate and glucose in the culture medium. At last, we further detected the fibrotic and glycolytic markers in human fibrotic and non-fibrotic heart tissues with masson staining, IF and western blot.Result: More collagen and glycolytic protein expressions were observed in the MI mice hearts. The mortality increased when mice were treated with 2-DG (100 mg/kg/d) after the MI surgery (Log-rank test, P < 0.05). When the dosage of 2-DG declined to 50 mg/kg/d, and the treatment was started on the 4th day after MI, no statistical difference of mortality between the two groups was observed (Log-rank test, P = 0.98). The collagen volume fraction was smaller and the fluorescence signal of α-smooth muscle actin (α-SMA) was weaker in mice treated with 2-DG than PBS. In vitro, 2-DG could significantly inhibit the increased expression of both the glycolytic and fibrotic proteins in the activated CF.Conclusion: Cardiac fibrosis is along with the enhancement of CF activation and glycolysis. Glycolysis inhibition can alleviate cardiac fibroblast activation and cardiac fibrosis after myocardial infarction.


2019 ◽  
Vol 2019 ◽  
pp. 1-16 ◽  
Author(s):  
Yanguo Xin ◽  
Wenchao Wu ◽  
Jing Qu ◽  
Xiaojiao Wang ◽  
Song Lei ◽  
...  

Mitofusin-2 (Mfn2) is a key outer mitochondrial membrane protein, which maintains normal mitochondrial dynamics and function. However, its role in cardiac fibroblast activation remains poorly understood. In the present study, a rat model of transverse aortic constriction (TAC) was established to observe the cardiac fibroblast activation in vivo. TGF-β1 treatment for 24 hours was used to induce cardiac fibroblast activation in vitro. As a result, the expression of Mfn2 decreased in the hypertrophic heart tissues and cardiac fibroblasts treated with TGF-β1. siMfn2 and adenovirus were applied to mediate Mfn2 gene silencing and overexpression in cardiac fibroblasts to elucidate the relationship between Mfn2 and cardiac fibroblast activation, as well as the possible underlying mechanisms. Knockdown of Mfn2 further promoted TGF-β1-induced cardiac fibroblast activation, while forced expression of Mfn2 attenuated this pathological reaction. The PERK/ATF4 pathway, one of the branches of endoplasmic reticulum (ER) stress, was identified to be involved in this process. Knockdown and overexpression of Mfn2 lead to aggravation or alleviation of the PERK/ATF4 pathway. Blocking this pathway by silencing ATF4 with siATF4 attenuated the pathological process. During the activation of cardiac fibroblasts, knockdown of Mfn2 also increased the production of reactive oxygen species (ROS), while ROS scavenger N-acetyl-l-cysteine (NAC) could attenuate the effect caused by knockdown of Mfn2. Our data suggested that inhibition of Mfn2 could promote cardiac fibroblast activation by activating the PERK/ATF4 signaling pathway and increasing the generation of ROS.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Zhengchuan Zhang ◽  
Ruogu Xu ◽  
Yang Yang ◽  
Chaoan Liang ◽  
Xiaolin Yu ◽  
...  

Abstract Background Micro/nano-textured hierarchical titanium topography is more bioactive and biomimetic than smooth, micro-textured or nano-textured titanium topographies. Bone marrow mesenchymal stem cells (BMSCs) and exosomes derived from BMSCs play important roles in the osseointegration of titanium implants, but the effects and mechanisms of titanium topography on BMSCs-derived exosome secretion are still unclear. This study determined whether the secretion behavior of exosomes derived from BMSCs is differently affected by different titanium topographies both in vitro and in vivo. Results We found that both micro/nanonet-textured hierarchical titanium topography and micro/nanotube-textured hierarchical titanium topography showed favorable roughness and hydrophilicity. These two micro/nano-textured hierarchical titanium topographies enhanced the spreading areas of BMSCs on the titanium surface with stronger promotion of BMSCs proliferation in vitro. Compared to micro-textured titanium topography, micro/nano-textured hierarchical titanium topography significantly enhanced osseointegration in vivo and promoted BMSCs to synthesize and transport exosomes and then release these exosomes into the extracellular environment both in vitro and in vivo. Moreover, micro/nanonet-textured hierarchical titanium topography promoted exosome secretion by upregulating RAB27B and SMPD3 gene expression and micro/nanotube-textured hierarchical titanium topography promoted exosome secretion due to the strongest enhancement in cell proliferation. Conclusions These findings provide evidence that micro/nano-textured hierarchical titanium topography promotes exosome biogenesis and extracellular secretion for enhanced osseointegration. Our findings also highlight that the optimized titanium topography can increase exosome secretion from BMSCs, which may promote osseointegration of titanium implants.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ryoichi Katsube ◽  
Kazuhiro Noma ◽  
Toshiaki Ohara ◽  
Noriyuki Nishiwaki ◽  
Teruki Kobayashi ◽  
...  

AbstractCancer-associated fibroblasts (CAFs) have an important role in the tumor microenvironment. CAFs have the multifunctionality which strongly support cancer progression and the acquisition of therapeutic resistance by cancer cells. Near-infrared photoimmunotherapy (NIR-PIT) is a novel cancer treatment that uses a highly selective monoclonal antibody (mAb)-photosensitizer conjugate. We developed fibroblast activation protein (FAP)-targeted NIR-PIT, in which IR700 was conjugated to a FAP-specific antibody to target CAFs (CAFs-targeted NIR-PIT: CAFs-PIT). Thus, we hypothesized that the control of CAFs could overcome the resistance to conventional chemotherapy in esophageal cancer (EC). In this study, we evaluated whether EC cell acquisition of stronger malignant characteristics and refractoriness to chemoradiotherapy are mediated by CAFs. Next, we assessed whether the resistance could be rescued by eliminating CAF stimulation by CAFs-PIT in vitro and in vivo. Cancer cells acquired chemoradiotherapy resistance via CAF stimulation in vitro and 5-fluorouracil (FU) resistance in CAF-coinoculated tumor models in vivo. CAF stimulation promoted the migration/invasion of cancer cells and a stem-like phenotype in vitro, which were rescued by elimination of CAF stimulation. CAFs-PIT had a highly selective effect on CAFs in vitro. Finally, CAF elimination by CAFs-PIT in vivo demonstrated that the combination of 5-FU and NIR-PIT succeeded in producing 70.9% tumor reduction, while 5-FU alone achieved only 13.3% reduction, suggesting the recovery of 5-FU sensitivity in CAF-rich tumors. In conclusion, CAFs-PIT could overcome therapeutic resistance via CAF elimination. The combined use of novel targeted CAFs-PIT with conventional anticancer treatments can be expected to provide a more effective and sensible treatment strategy.


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