scholarly journals YKL-40 Aggravates Early-Stage Atherosclerosis by Inhibiting Macrophage Apoptosis in an Aven-dependent Way

Author(s):  
Wei Huan ◽  
Liu Yandong ◽  
Wang Chao ◽  
Zou Sili ◽  
Bai Jun ◽  
...  

Objective: programmed cell removal in atherosclerotic plaques plays a crucial role in retarding lesion progression. Macrophage apoptosis has a critical role in PrCR, especially in early-stage lesions. YKL-40 has been shown to be elevated as lesions develop and is closely related to macrophages. This study aimed to determine the effect of YKL-40 on regulating macrophage apoptosis and early-stage atherosclerosis progression.Research design and Methods: The correlations among the expression level of YKL-40, the area of early-stage plaque, and the macrophage apoptosis rate in plaques have been shown in human carotid atherosclerotic plaques through pathological and molecular biological detection. These results were successively confirmed in vivo (Ldlr−/- mice treated by YKL-40 recombinant protein/neutralizing antibody) and in vitro (macrophages that Ykl40 up-/down-expressed) experiments. The downstream targets were predicted by iTRAQ analysis.Results: In early-stage human carotid plaques and murine plaques, the YKL-40 expression level had a significant positive correlation with the area of the lesion and a significant negative correlation with the macrophage apoptosis rate. In vivo, the plaque area of aortic roots was significantly larger in the recomb-YKL-40 group than that in IgG group (p = 0.0247) and was significantly smaller in the anti-YKL-40 group than in the IgG group (p = 0.0067); the macrophage apoptosis rate of the plaque in aortic roots was significantly lower in the recomb-YKL-40 group than that in IgG group (p = 0.0018) and was higher in anti-YKL-40 group than that in VC group. In vitro, the activation level of caspase-9 was significantly lower in RAW264.7 with Ykl40 overexpressed than that in controls (p = 0.0054), while the expression level of Aven was significantly higher than that in controls (p = 0.0031). The apoptosis rate of RAW264.7 treated by recomb-YKL40 was significantly higher in the Aven down-regulated group than that in the control group (p < 0.001). The apoptosis inhibitor Aven was confirmed as the target molecule of YKL-40. Mechanistically, YKL-40 could inhibit macrophage apoptosis by upregulating Aven to suppress the activation of caspase-9.Conclusion: YKL-40 inhibits macrophage apoptosis by upregulating the apoptosis inhibitor Aven to suppress the activation of caspase-9, which may impede normal PrCR and promote substantial accumulation in early-stage plaques, thereby leading to the progression of atherosclerosis.

Author(s):  
Renate W. Boekhoven ◽  
Marcel C. M. Rutten ◽  
Marc R. H. M. van Sambeek ◽  
Frans N. van de Vosse

Ruptured atherosclerotic plaques in the carotid artery are the main cause of stroke (70–80%). To prevent it, carotid endarterectomy is the procedure of choice in patients with a recent symptomatic 70–99% stenosis. Today, the selection of candidates is based on stenosis size only. However, endarterectomy is beneficial for only 1 out of 6 patients [1], the patients with unstable plaques (Fig. 1). Knowledge of mechanical properties of different components in the atherosclerotic arteries is important, because it will allow the identification of plaque stability at an early stage.


Author(s):  
Yangyang Liu ◽  
Yonglu Li ◽  
Wen Chen ◽  
Xiang Ye ◽  
Ruoyi Jia ◽  
...  

Abstract: Tetrastigma hemsleyanum has been regarded as an anticancer food in China. However, its corresponding mechanisms remains unclear. Thus, in this study, the antitumor activity of flavones-rich fraction of root of Tetrastigma hemsleyanum (FRTH) was investigated in vitro and in vivo. The results indicated that FRTH could inhibit the proliferation and migration of HepG2 cells in vitro by PI3K/AKT pathway. FRTH could increase the ROS level and change the mitochondrial membrane potential (MMP) in HepG2 cells. In addition, FRTH treatment (300, 600 mg/kg BW) significantly suppressed tumor growth on HepG2 tumor-bearing nude mice. Besides, immunohistochemistry assays and western blotting revealed that FRTH enhanced the expression level of Bax/Bcl-2, cytochrome C, Caspase-3, caspase-9, Cleaved-caspase-3, and downregulated the expression level of CD31, ki67 and VEGF in HepG2 tumor-bearing mice. Our study suggests Tetrastigma hemsleyanum as a promising candidate medicine for liver cancer treatment.


Molecules ◽  
2019 ◽  
Vol 24 (6) ◽  
pp. 1072 ◽  
Author(s):  
Sanna Hellberg ◽  
Johanna Silvola ◽  
Heidi Liljenbäck ◽  
Max Kiugel ◽  
Olli Eskola ◽  
...  

Atherosclerosis is characterized by the accumulation of oxidized lipids in the artery wall, which triggers an inflammatory response. Oxidized low-density lipoprotein (ox-LDL) presents amyloid-like structural properties, and different amyloid species have recently been recognized in atherosclerotic plaques. Therefore, we studied the uptake of the amyloid imaging agent [18F]Flutemetamol in atherosclerotic plaques. The binding of [18F]Flutemetamol to human carotid artery plaque was studied in vitro. In vivo uptake of the tracer was studied in hypercholesterolemic IGF-II/LDLR−/−ApoB100/100 mice and C57BL/6N controls. Tracer biodistribution was studied in vivo with PET/CT, and ex vivo by gamma counter and digital ex vivo autoradiography. The presence of amyloid, ox-LDL, and macrophages in the plaques was examined by immunohistochemistry. [18F]Flutemetamol showed specific accumulation in human carotid plaque, especially in areas positive for amyloid beta. The aortas of IGF-II/LDLR−/−ApoB100/100 mice showed large thioflavin-S-positive atherosclerotic plaques containing ox-LDL and macrophages. Autoradiography revealed 1.7-fold higher uptake in the plaques than in a lesion-free vessel wall, but no difference in aortic tissue uptake between mouse strains were observed in the in vivo PET/CT. In conclusion, [18F]Flutemetamol binds to amyloid-positive areas in human atherosclerotic plaques. Further studies are warranted to clarify the uptake mechanisms, and the potential of the tracer for in vivo imaging of atherosclerosis in patients.


2017 ◽  
Vol 41 (1) ◽  
pp. 163-172 ◽  
Author(s):  
Haiting Huang ◽  
Yanwu You ◽  
Xu Lin ◽  
Chunrong Tang ◽  
Xiangjun Gu ◽  
...  

Background/Aims: Transforming growth factor beta 1 (TGF-β1) plays a critical role in the pathogenesis of glomerulosclerosis. The purpose of this study was to examine the effects of inhibition of transient receptor potential cation channel C6 (TRPC6) on podocyte injury induced by TGF-β1 via nephrin and desmin mechanisms. Methods: A rat model of nephropathy was first induced by intravenous injections of adriamycin to determine TRPC6 signal pathway engaged in glomerulosclerosis in vivo. Conditionally immortalized podocytes were cultured in vitro and they were divided into four groups: control; TGF-β1 treatment; TGF-β1 with TRPC6 knockdown and TGF-β1 without TRPC6 knockdown. Real time RT-PCR and Western blot analysis were employed to determine the mRNA and protein of expression of nephrin, desmin and caspase-9, respectively. Flow cytometry was used to examine the apoptotic rate of podocytes and DAPI fluorescent staining was used to determine apoptotic morphology. Results: In vivo experiment, adriamycin significantly upregulated the protein expression of TGF-β1, TRPC6, desmin and caspase-9, and decreased nephrin. Consistent with the latter results, in vitro experiment mRNA and protein expression of desmin and caspase-9 was increased in cultured TGF-β1-treated podocytes, whereas nephrin was declined as compared with the control group. Importantly, TRPC6 knockdown significantly attenuated the upregulated desmin and caspase-9, and alleviated impairment of nephrin induced by TGF-β1. Moreover, typical morphologic features were presented in apoptotic podocytes. The number of apoptotic podocytes was increased after exposure to TGF-β1 and this was alleviated after TRPC6 knockdown. TRPC6 knockdown also decreased an apoptosis rate of TGF-β1-treated podocytes. Note that negative TRPC6 transfection control failed to alter an increase of the apoptosis rate in TGF-β1-treated podocytes. Conclusions: TGF-β1 induced by glomerulosclerosis impairs the protein expression of nephrin and amplifies the protein expression of desmin and caspase -9 via TRPC6 signal pathway. Inhibition of TRPC6 alleviates these changes in podocytes-treated with TGF-β1 and attenuated apoptosis of podocytes. Our data suggest that TRPC6 signal plays an important role in mediating TGF-β1-induced podocyte injury via nephrin, desmin and caspase-9. Results of the current study also indicate that blocking TRPC6 signal pathway has a protective effect on podocyte injury. Targeting one or more of these signaling molecules may present new opportunities for treatment and management of podocyte injury observed in glomerulosclerosis.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Dexin Shen ◽  
Yayun Fang ◽  
Fenfang Zhou ◽  
Zhao Deng ◽  
Kaiyu Qian ◽  
...  

Abstract Background CDCA3 is an important component of the E3 ligase complex with SKP1 and CUL1, which could regulate the progress of cell mitosis. CDCA3 has been widely identified as a proto-oncogene in multiple human cancers, however, its role in promoting human bladder urothelial carcinoma has not been fully elucidated. Methods Bioinformatic methods were used to analyze the expression level of CDCA3 in human bladder urothelial carcinoma tissues and the relationship between its expression level and key clinical characteristics. In vitro studies were performed to validate the specific functions of CDCA3 in regulating cell proliferation, cell migration and cell cycle process. Alterations of related proteins was investigated by western blot assays. In vivo studies were constructed to validate whether silencing CDCA3 could inhibit the proliferation rate in mice model. Results Bioinformatic analysis revealed that CDCA3 was significantly up-regulated in bladder urothelial carcinoma samples and was related to key clinical characteristics, such as tumor grade and metastasis. Moreover, patients who had higher expression level of CDCA3 tend to show a shorter life span. In vitro studies revealed that silencing CDCA3 could impair the migration ability of tumor cells via down-regulating EMT-related proteins such as MMP9 and Vimentin and inhibit tumor cell growth via arresting cells in the G1 cell cycle phase through regulating cell cycle related proteins like p21. In vivo study confirmed that silencing CDCA3 could inhibit the proliferation of bladder urothelial carcinoma cells. Conclusions CDCA3 is an important oncogene that could strengthen the migration ability of bladder urothelial carcinoma cells and accelerate tumor cell growth via regulating cell cycle progress and is a potential biomarker of bladder urothelial carcinoma.


2017 ◽  
Vol 2017 ◽  
pp. 1-8
Author(s):  
Lixia Ji ◽  
Lixia Cheng ◽  
Zhihong Yang

Objective.Lens osmotic expansion, provoked by overactivated aldose reductase (AR), is the most essential event of sugar cataract. Chloride channel 3 (Clcn3) is a volume-sensitive channel, mainly participating in the regulation of cell fundamental volume, and P-glycoprotein (P-gp) acts as its modulator. We aim to study whether P-gp and Clcn3 are involved in lens osmotic expansion of galactosemic cataract.Methods and Results.In vitro, lens epithelial cells (LECs) were primarily cultured in gradient galactose medium (10–60 mM), more and more vacuoles appeared in LEC cytoplasm, and mRNA and protein levels of AR, P-gp, and Clcn3 were synchronously upregulated along with the increase of galactose concentration. In vivo, we focused on the early stage of rat galactosemic cataract, amount of vacuoles arose from equatorial area and scattered to the whole anterior capsule of lenses from the 3rd day to the 9th day, and mRNA and protein levels of P-gp and Clcn3 reached the peak around the 9th or 12th day.Conclusion. Galactosemia caused the osmotic stress in lenses; it also markedly leads to the upregulations of AR, P-gp, and Clcn3 in LECs, together resulting in obvious osmotic expansion in vitro and in vivo.


2017 ◽  
Vol 42 (4) ◽  
pp. 1469-1480 ◽  
Author(s):  
Xu Lin ◽  
Xintng Zhen ◽  
Haiting Huang ◽  
Haohao Wu ◽  
Yanwu You ◽  
...  

Background/Aims: Transforming growth factor beta 1 (TGF-β1) plays a critical role in the pathogenesis of glomerulosclerosis. The purpose of this study was to examine the effects of inhibition of miR-155 on podocyte injury induced by TGF-β1 and to determine further molecular mediators involved in the effects of miR-155. Methods: Conditionally immortalized podocytes were cultured in vitro and they were divided into four groups: control; TGF-β1 treatment; TGF-β1 with miR-155 knockdown [using antisense oligonucleotides against miR-155 (ASO-miR-155)] and TGF-β1 with negative control antisense oligonucleotides (ASO-NC). Real time RT-PCR and Western blot analysis were employed to determine the mRNA and protein expression of nephrin, desmin and caspase-9, respectively. Flow cytometry was used to examine the apoptotic rate of podocytes and DAPI fluorescent staining was used to determine apoptotic morphology. In addition, we examined the levels of miR-155, TGF-β1, nephrin, desmin and caspase-9 in glomerular tissues of nephropathy induced by intravenous injections of adriamycin in rats. Results: mRNA and protein expression of desmin and caspase-9 was increased in cultured TGF-β1-treated podocytes, whereas nephrin was decreased as compared with the control group. Importantly, miR-155 knockdown significantly attenuated upregulation of desmin and caspase-9, and alleviated impairment of nephrin induced by TGF-β1. Moreover, the number of apoptotic podocytes was increased after exposure to TGF-β1 and this was alleviated after miR-155 knockdown. Knocking down miR-155 also decreased an apoptosis rate of TGF-β1-treated podocytes. Note that negative control antisense oligonucleotides failed to alter an increase of the apoptosis rate in TGF-β1-treated podocytes. Consistent with in vitro results, expression of miR-155, TGF-β1, desmin and caspase-9 was increased and nephrin was decreased in glomerular tissues with nephropathy in vivo experiments. Conclusions: TGF-β1 impairs the protein expression of nephrin and amplifies the protein expression of desmin and caspase -9 via miR-155 signal pathway. Inhibition of miR-155 alleviates these changes in podocytes-treated with TGF-β1 and attenuated apoptosis of podocytes. Our data suggest that miR-155 plays a role in mediating TGF-β1-induced podocyte injury via nephrin, desmin and caspase-9. Results of the current study also indicate that blocking miR-155 signal has a protective effect on podocyte injury. Targeting one or more of these signaling molecules may present new opportunities for treatment and management of podocyte injury observed in glomerulosclerosis.


2019 ◽  
Vol 133 (11) ◽  
pp. 1215-1228 ◽  
Author(s):  
Yu Sun ◽  
Juan Guan ◽  
Yunfeng Hou ◽  
Fei Xue ◽  
Wei Huang ◽  
...  

Abstract Background: Although junctional adhesion molecule-like protein (JAML) has recently been implicated in leukocyte recruitment during inflammation and wound repair, its role in atherosclerosis remains to be elucidated. Methods and results: First, we showed that JAML was strongly expressed in atherosclerotic plaques of cardiovascular patients. Similar results were obtained with atherosclerotic plaques of ApoE−/− mice. Co-immunofluorescence staining showed that JAML was mainly expressed in macrophages. Enhanced expression of JAML in cultured macrophages was observed following exposure of the cells to oxLDL. The functional role of JAML in atherosclerosis and macrophages function was assessed by interference of JAML with shRNA in vivo and siRNA in vitro. Silencing of JAML in mice significantly attenuated atherosclerotic lesion formation, reduced necrotic core area, increased plaque fibrous cap thickness, decreased macrophages content and inflammation. In addition, histological staining showed that JAML deficiency promoted plaques to stable phenotype. In vitro, JAML siRNA treatment lowered the expression of inflammatory cytokines in macrophages treated with oxLDL. The mechanism by which JAML mediated the inflammatory responses may be related to the ERK/NF-κB activation. Conclusions: Our results demonstrated that therapeutic drugs which antagonize the function of JAML may be a potentially effective approach to attenuate atherogenesis and enhance plaque stability.


2021 ◽  
Author(s):  
Yipu Wang ◽  
Dong Mei ◽  
Xinyi Zhang ◽  
Da-Hui Qu ◽  
Ju Mei ◽  
...  

With increase of social aging, Alzheimer's disease (AD) has been one of the serious diseases threatening human health. The occurrence of A<i>β </i>fibrils<i> </i>or plaques is recognized as the hallmark of AD.<i> </i>Currently, optical imaging has stood out to be a promising technique for the imaging of A<i>β</i> fibrils/plaques and the diagnosis of AD. However, restricted by their poor blood-brain barrier (BBB) penetrability, short-wavelength excitation and emission, and aggregation-caused quenching (ACQ) effect, the clinically used gold-standard optical probes such as <a>thioflavin</a> T (ThT) and thioflavin S (ThS), are not effective enough in the early diagnosis of AD <i>in vivo</i>. Herein, we put forward an “all-in-one” design principle and demonstrate its feasibility in developing high-performance fluorescent probes which are specific to A<i>β</i> fibrils/plaques and promising for super-early <i>in</i>-<i>vivo</i> diagnosis of AD. As a proof of concept, a simple rod-like amphiphilic NIR fluorescent AIEgen, i.e., AIE-CNPy-AD, is developed by taking the specificity, BBB penetration ability, deep-tissue penetration capacity, high signal-to-noise ratio (SNR) into consideration. AIE-CNPy-AD is constituted by connecting the electron-donating and accepting moieties through single bonds and tagging with a propanesulfonate tail, giving rise to the NIR fluorescence, aggregation-induced emission (AIE) effect, amphiphilicity, and rod-like structure, which in turn result in high binding-affinity and excellent specificity to A<i>β</i> fibrils/plaques, satisfactory ability to penetrate BBB and deep tissues, ultrahigh SNR and sensitivity, and high-fidelity imaging capability. <i>In-vitro, ex-vivo,</i> and <i>in-vivo</i> <a>identifying of A<i>β</i> fibrils/plaques</a> in different strains of mice indicate that AIE-CNPy-AD holds the universality to the detection of A<i>β</i> fibrils/plaques. It is noteworthy that AIE-CNPy-AD is even able to trace the small and sparsely distributed A<i>β</i> fibrils/plaques in very young AD model mice such as 4-month-old APP/PS1 mice which are reported to be the youngest mice to have A<i>β</i> deposits in brains, suggesting its great potential in diagnosis and intervention of AD at a super-early stage.


2020 ◽  
Author(s):  
María A. Duque-Correa ◽  
David Goulding ◽  
Claire Cormie ◽  
Catherine Sharpe ◽  
Judit Gali Moya ◽  
...  

ABSTRACTHundreds of millions of people are infected with whipworms (Trichuris trichiura), large metazoan parasites that live in the caecum and proximal colon. Whipworms inhabit distinct multi-intracellular epithelial burrows that have been described as syncytial tunnels. However, the interactions between first-stage (L1) larvae and the host epithelia that determine parasite invasion and establishment in the syncytium remain unclear. In vivo experiments investigating these events have been severely hampered by the limited in situ accessibility to intracellular infective larvae at the bottom of the crypts of Lieberkühn, and the lack of genetic tools such as fluorescent organisms that are readily available for other pathogens but not parasitic nematodes. Moreover, cell lines, which do not mimic the complexity of the intestinal epithelium, have been unsuccessful in supporting infection by whipworm larvae. Here, we show that caecaloids grown in an open crypt-like conformation recapitulate the caecal epithelium. Using this system, we establish in vitro infections with T. muris L1 larvae for the first-time, and provide clear evidence that syncytial tunnels are formed at this early stage. We show that larval whipworms are completely intracellular but woven through multiple cells. Using the caecaloids, we are able to visualise the pathways taken by the larvae as they burrow through the epithelial cells. We also demonstrate that larvae degrade the mucus layers overlaying the epithelium, enabling them to access the cells below. We show that early syncytial tunnels are composed of enterocytes and goblet cells that are alive and actively interacting with the larvae during the first 24 h of the infection. Progression of infection results in damage to host cells and by 72 h post-infection, we show that desmosomes of cells from infected epithelium widen and some host cells appear to become liquified. Collectively, our work unravels processes mediating the intestinal epithelium invasion by whipworms and reveals new specific interactions between the host and the parasite that allow the whipworm to establish on its multi-intracellular niche. Our study demonstrates that caecaloids can be used as a relevant in vitro model to investigate the infection biology of T. muris during the early colonisation of its host.


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