Proliferative Vascular Smooth Muscle Cells Stimulate Extracellular Matrix Production via Osteopontin/p38 MAPK Signaling Pathway

Cardiology ◽  
2021 ◽  
pp. 1-10
Author(s):  
Huawei Pei ◽  
Haiyue Zhang ◽  
Chuan Tian ◽  
Xiaogang Sun ◽  
Xiangyang Qian ◽  
...  

<b><i>Introduction:</i></b> Extracellular matrix disorder and cellular phenotype transformation are the major histopathological features associated with ascending aortic aneurysms. Rare studies have investigated the relationship between cellular phenotype transformation and the abnormalities of the matrix constituents. In this study, we investigated whether the cellular phenotype transformation resulted in the extracellular matrix disorder. <b><i>Methods:</i></b> Aortic samples were obtained from 20 patients undergoing operations for ascending aortic aneurysms. Control aortic samples were obtained from 15 patients who underwent coronary artery bypass graft. The protein levels of osteopontin (OPN), collagen, and elastin were examined using Western blot, and quantitative reverse transcriptase-PCR was used to analyze the mRNA expression of collagen and elastin. In vitro experiment, vascular smooth muscle cells (VSMCs) were treated with recombinant human OPN (rh-OPN) or p38 MAPK inhibitor (SB203580) to investigate whether OPN and p38 MAPK regulated the expression of collagen and elastin. <b><i>Results:</i></b> The protein level of OPN and collagen III increased in ascending aortic aneurysm samples, compared with controls (<i>p</i> &#x3c; 0.05). There was no difference in the protein level of elastin between aneurysm tissues and the controls. VSMCs treated with rh-OPN increased the collagen III and elastin protein level and mRNA expression (<i>p</i> &#x3c; 0.05). Cells treated with SB203580 decreased the collagen III and elastin protein level and mRNA expression (<i>p</i> &#x3c; 0.05). Furthermore, VSMCs incubated with SB203580 reduced the rh-OPN-induced production of collagen III and elastin (<i>p</i> &#x3c; 0.05). <b><i>Conclusion:</i></b> OPN, the proliferative VSMCs maker, increased the expression of extracellular matrix. OPN/p38 MAPK signaling pathways may protect against ascending aortic aneurysm progression.

2018 ◽  
Vol 1 (3) ◽  
Author(s):  
Tatiana Nemirovskaya ◽  
Svetlana Belova ◽  
Boris Shenkman ◽  
Ekaterina Mochalova

Objective Unloading causes rapid skeletal muscle atrophy mainly due to the increased protein degradation. Muscle proteolysis results from the activation of ubiquitin-proteasome systems. The ubiquitination proteins are carried out by muscle-specific E3 ubiquitin ligases – MuRF-1 and MAFbx. It is known that MuRF-1 and MAFbx expression significantly increases on the third day of muscle unloading. We tested the hypothesis that p38 MAPK participates in the regulation of E3 ligases expression and the development of skeletal muscle atrophy during unloading. To check this idea we inhibited p38 MAPK by VX-745. Methods 21 male Wistar rats were divided into 3 groups (7 rats in each group): intact control (C), rats suspended for 3 days (HS) and rats suspended and injected i.p. with VX-745 (10 mg/kg/day) (VX). The hindlimb suspension was carried out according to Morey-Holton technique. The animals were anaesthetised with an i.p. injection of tribromoethanol (240 mg/kg). Under anesthesia, the m.soleus were excised, frozen in liquid nitrogen, and stored at -80°C until further analysis. All procedures with the animals were approved by the Biomedicine Ethics Committee of the Institute of Biomedical Problems of the Russian Academy of Sciences/Physiology section of the Russian Bioethics Committee. The statistical analysis was performed using the REST 2009 v.2.0.12 and Origin Pro programs at the significance level set at 0,05. The results are given as median in percent and interquartile range (0.25-0.75). Results The muscle weight in HS group was significantly reduced (72,3±2,5 mg) compared to C (83,0±3 mg), p<0.05, while the soleus weight of VX group didn’t differ from the control (84.2±5 mg). The MuRF1 mRNA expression was elevated dramatically in HS group (165 (138-210) %) when compared with the control (100 (64.6-112.5) %), p<0.05.  In the VX group the level of MuRF1 mRNA expression (127 (105-138) %) didn’t differ from the control group. The MAFbx mRNA expression was observed to increase equally in both suspended groups (294 (265-342) % and (271 (239-309) %).) vs C (100 (91-106) %) so, VX-745 administration did not have any significant effect on its expression. We also found that the level of ubiquitin mRNA expression in the soleus of HS rats was higher (423 (325-485) %) in comparison with the C group (100 (78-166) %, p<0.05) while VX-745 injection prevented increasing the  mRNA ubiquitin expression (200 (190-237) %). We discovered that the elevation of calpain-1 mRNA expression upon HS was prevented by VX-745 administration and its level didn’t differ from the control group (C - 100 (97-105) %, HS – 120 (116-133) %, VX - 107 (100-115) %, p<0.05). Conclusions Thus, the results indicate that the p38 MAPK signaling pathway takes part in the regulation of E3-ligase MuRF1 but not MAFbx expression. The p38 MAPK inhibition prevents muscle atrophy and the elevation of ubiquitin and calpain mRNA expression at the early stage of hindlimb unloading. This work was supported by RFBR grant No.17-04-01838.


2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Ning Liu ◽  
Jiao Feng ◽  
Xiya Lu ◽  
Zhilu Yao ◽  
Qing Liu ◽  
...  

Objective. Liver fibrosis is a consequence of wound-healing responses to chronic liver insult and may progress to liver cirrhosis if not controlled. This study investigated the protection against liver fibrosis by isorhamnetin. Methods. Mouse models of hepatic fibrosis were established by intraperitoneal injection of carbon tetrachloride (CCl4) or bile duct ligation (BDL). Isorhamnetin 10 or 30 mg/kg was administered by gavage 5 days per week for 8 weeks in the CCl4 model and for 2 weeks in the BDL model. Protein and mRNA expressions were assayed by western blotting, immunohistochemistry, and quantitative real-time polymerase chain reaction. Results. Isorhamnetin significantly inhibited liver fibrosis in both models, inhibiting hepatic stellate cell (HSC) activation, extracellular matrix (ECM) deposition, and autophagy. The effects were associated with downregulation of transforming growth factor β1 (TGF-β1) mediation of Smad3 and p38 mitogen-activated protein kinase (MAPK) signaling pathways. Conclusion. Isorhamnetin protected against liver fibrosis by reducing ECM formation and autophagy via inhibition of TGF-β1-mediated Smad3 and p38 MAPK signaling pathways.


2021 ◽  
Author(s):  
Jing Ma ◽  
Ranran Wang ◽  
Ting Chen ◽  
Shaowei Jiang ◽  
Ajing Xu

Abstract Parkinson’s disease (PD) is a common neurodegenerative disorder of the central nervous system. However, the pathogenetic mechanisms of PD are far from understood. The aim of this study was to determine the protective effect of baicalin in a Caenorhabditis elegans model of PD. C. elegans worms were stimulated for 24 h with 6-hydroxydopamine (6-OHDA, 50 mM) and treated with or without baicalin (1, 10, or 100 μM). At all tested concentrations, baicalin improved the reversal and omega turn behavioral phenotypes, as well as the survival, of 6-OHDA-stimulated worms. It also inhibited 6-OHDA-induced oxidative stress by decreasing malondialdehyde levels, increasing superoxide dismutase, glutathione reductase, catalase, and glutathione levels and up-regulating mRNA expression of the antioxidant-related genes sod-1, sod-2, sod-3, daf-2, and daf-16. Additionally, it significantly decreased the expression of the apoptosis-related gene ced-3 and increased that of the anti-apoptosis-related gene ced-9. The expression levels of cleaved caspase-3 and B-cell lymphoma 2 in 6-OHDA-treated worms were reversed by baicalin. Apoptosis was suppressed by 6-OHDA in loss-of-function strains via the p38 mitogen-activated protein kinase (MAPK) signaling pathway. Furthermore, the apoptotic effects of 6-OHDA were blocked in sek-1 and pmk-1 mutants. Finally, the mRNA expression of sek-1 and pmk-1 and the protein expression of p38 MAPK and stress-activated protein kinase/extracellular signal-regulated kinase 1 were up-regulated by 6-OHDA and reversed by baicalin. Baicalin may protect against 6-OHDA injury by inhibiting apoptosis and decreasing oxidative stress through the p38 MAPK signaling pathway.


Author(s):  
Kristin Schram ◽  
Sabrina Girolamo ◽  
Siham Madani ◽  
Diana Munoz ◽  
Farah Thong ◽  
...  

AbstractA clear association between obesity and heart failure exists and a significant role for leptin, the product of the obese gene, has been suggested. One aspect of myocardial remodeling which characterizes heart failure is a disruption in the balance of extracellular matrix synthesis and degradation. Here we investigated the effects of leptin on matrix metalloproteinase (MMP) activity, tissue inhibitor of metalloproteinase (TIMP) expression, as well as collagen synthesis in HL-1 cardiac muscle cells. Gelatin zymographic analysis of MMP activity in conditioned media showed that leptin enhanced MMP-2 activity in a dose- and time-dependent manner. Leptin is known to stimulate phosphorylation of p38 MAPK in cardiac cells and utilization of the p38 MAPK inhibitor, SB203580, demonstrated that this kinase also plays a role in regulating several extracellular matrix components, such that inhibition of p38 MAPK signaling prevented the leptin-induced increase in MMP-2 activation. We also observed that leptin enhanced collagen synthesis determined by both proline incorporation and picrosirius red staining of conditioned media. Pro-collagen type-I and pro-collagen type-III expression, measured by real-time PCR and Western blotting were also increased by leptin, effects which were again attenuated by SB203580. In summary, these results demonstrate the potential for leptin to play a role in mediating myocardial ECM remodeling and that the p38 MAPK pathway plays an important role in mediating these effects.


2010 ◽  
Vol 298 (3) ◽  
pp. H945-H955 ◽  
Author(s):  
Lie Gao ◽  
Yulong Li ◽  
Harold D. Schultz ◽  
Wei-Zhong Wang ◽  
Wei Wang ◽  
...  

Elevated central angiotensin II (ANG II) plays a critical role in the sympathoexcitation of chronic heart failure (CHF) by stimulating upregulated ANG II type 1 receptors (AT1R) in the rostral ventrolateral medulla (RVLM). However, the link between enhanced ANG II signaling and alterations in the electrophysiological characteristics of neurons in the RVLM remains unclear. In the present experiments, we screened for potentially altered genes in the medulla of rats with CHF that are directly related to neuronal membrane conductance using the Rat Genome 230 2.0 Array GeneChip. We found that CHF rats exhibited a 2.1-fold reduction in Kv4.3 gene expression, one of the main voltage-gated K+ channels, in the medulla. Real-time RT-PCR and Western blot analysis confirmed the downregulation of Kv4.3 in the RVLM of CHF rats. In intact animals, we found that microinjection of the voltage-gated potassium channel blocker, 4-aminopyridine, into the RVLM evoked a sympathoexcitation and hypertension in both normal and CHF rats. CHF rats exhibited smaller responses to 4-aminopyridine than did normal rats. Finally, we used a neuronal cell line (CATH.a neurons) to explore the effect of ANG II on Kv4.3 expression and function. We found that ANG II treatment significantly downregulated mRNA and protein expression of Kv4.3 and decreased the A-type K+ current. Employing this cell line, we also found that the ANG II-induced inhibition of Kv4.3 mRNA expression was attenuated by the superoxide scavenger Tempol and the p38 MAPK inhibitor SB-203580. The effects of ANG II were abolished by the AT1R antagonist losartan. We conclude that the sympathoexcitation observed in the CHF state may be due, in part, to an ANG II-induced downregulation of Kv4.3 expression and subsequent decrease in K+ current, thereby increasing the excitability of neurons in the RVLM. The ANG II-induced inhibition of Kv4.3 mRNA expression was mediated by ANG II-AT1R-ROS-p38 MAPK signaling.


2013 ◽  
Vol 304 (2) ◽  
pp. E176-E186 ◽  
Author(s):  
Quan Jiang ◽  
Anderson O. L. Wong

Pituitary hormones can act locally via autocrine/paracrine mechanisms to modulate pituitary functions, which represents an interesting aspect of pituitary regulation other than the traditional hypothalamic input and feedback signals from the periphery. Somatolactin, a member of the growth hormone (GH)/prolactin (PL) family, is a pleiotropic hormone with diverse functions, but its pituitary actions are still unknown. Recently, two SL isoforms, SLα and SLβ, have been cloned in grass carp. Based on the sequences obtained, recombinant proteins of carp SLα and SLβ with similar bioactivity in inducing pigment aggregation in carp melanophores were produced. In carp pituitary cells, SLα secretion and cell content were elevated by static incubation with recombinant carp SLα and SLβ, respectively. These stimulatory actions occurred with a parallel rise in SLα mRNA level with no changes in SLβ secretion, cell content, and gene expression. In contrast, SLα mRNA expression could be reduced by removing endogenous SLα and SLβ with immunoneutralization. At the pituitary cell level, SLα release, cell content, and mRNA expression induced by carp SLα and SLβ could be blocked by inhibiting JAK2/STAT5, PI3K/Akt, MEK1/2, and p38 MAPK, respectively. Furthermore, SLα and SLβ induction also triggered rapid phosphorylation of STAT5, Akt, MEK1/2, ERK1/2, MKK3/6, and p38 MAPK. These results suggest that 1) SLα and SLβ produced locally in the carp pituitary can serve as novel autocrine/paracrine stimulators for SLα secretion and synthesis and 2) SLα production induced by local release of SLα and SLβ probably are mediated by the JAK2/STAT5, PI3K/Akt, and MAPK signaling pathways.


2010 ◽  
Vol 299 (5) ◽  
pp. C1162-C1170 ◽  
Author(s):  
Zhongxiao Wan ◽  
A. Brianne Thrush ◽  
Melanie Legare ◽  
Bruce C. Frier ◽  
Lindsey N. Sutherland ◽  
...  

Fatty acid reesterification in adipose tissue is dependent on the generation of glycerol 3-phosphate, and, at least in rodent adipose tissue, this appears to occur primarily through glyceroneogenesis. A key enzyme in this process is pyruvate dehydrogenase kinase 4 (PDK4). PDK4 is induced in white adipose tissue by thiazolidinediones (TZDs) and the inhibition or knockdown of PDK4 inhibits TZD-induced increases in glyceroneogenesis. Since TZDs have many unwanted side effects, we were interested in identifying alternative mechanisms that could regulate PDK4 mRNA expression in white adipose tissue. In this regard we hypothesized that exercise, fasting, and epinephrine would increase PDK4 mRNA levels in rat epididymal adipose tissue. We further postulated that the p38 mitogen-activated protein kinase (MAPK) and 5′-AMP-activated protein kinase (AMPK) signaling pathways would control PDK4 mRNA expression in cultured adipose tissue. Exercise, fasting, and in or ex vivo epinephrine treatment increased PDK4 mRNA levels. These perturbations did not increase the expression of PDK1, -2, or -3. Pyruvate dehydrogenase phosphorylation was increased after an overnight fast and 4 h after the cessation of exercise. In cultured adipose tissue, epinephrine increased p38 and AMPK signaling; however, the direct activation of AMPK by AICAR or metformin led to reductions in PDK4 mRNA levels. The p38 inhibitor SB202190 reduced epinephrine-mediated increases in p38 MAPK activation without altering hormone-sensitive lipase or AMPK phosphorylation or attenuating epinephrine-induced increases in lipolysis. Reductions in p38 MAPK signaling were associated with decreases in PDK4 mRNA expression. The inhibition of peroxisome proliferator-activated receptor-γ (PPARγ) also attenuated the induction of PDK4. Our results are the very first to demonstrate an epinephrine-mediated regulation of PDK4 mRNA levels in white adipose tissue and suggest that p38 MAPK and PPARγ could be involved in this pathway.


2021 ◽  
Vol 12 ◽  
Author(s):  
Corey Wittig ◽  
Robert Szulcek

Cardiovascular pathology is often accompanied by changes in relative content and/or ratios of structural extracellular matrix (ECM) proteins within the heart and elastic vessels. Three of these proteins, collagen-I, collagen-III, and elastin, make up the bulk of the ECM proteins in these tissues, forming a microenvironment that strongly dictates the tissue biomechanical properties and effectiveness of cardiac and vascular function. In this review, we aim to elucidate how the ratios of collagen-I to collagen-III and elastin to collagen are altered in cardiovascular diseases and the aged individuum. We elaborate on these major cardiovascular ECM proteins in terms of structure, tissue localization, turnover, and physiological function and address how their ratios change in aging, dilated cardiomyopathy, coronary artery disease with myocardial infarction, atrial fibrillation, aortic aneurysms, atherosclerosis, and hypertension. To the end of guiding in vitro modeling approaches, we focus our review on the human heart and aorta, discuss limitations in ECM protein quantification methodology, examine comparability between studies, and highlight potential in vitro applications. In summary, we found collagen-I relative concentration to increase or stay the same in cardiovascular disease, resulting in a tendency for increased collagen-I/collagen-III and decreased elastin/collagen ratios. These ratios were found to fall on a continuous scale with ranges defining distinct pathological states as well as a significant difference between the human heart and aortic ECM protein ratios.


Sign in / Sign up

Export Citation Format

Share Document