scholarly journals Nef Alleles derived from HIV-Positive Patients with Pulmonary Hypertension Affect Production and Function of Exosomes in Endothelial Colony Forming Cells

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Arthur Cross-Najafi ◽  
Tyler Colbert ◽  
Sarvesh Chelvanambi ◽  
Sharilyn Almodovar ◽  
Sonia Flores ◽  
...  

Background: The HIV positive population has a > 300 fold higher risk for developing pulmonary hypertension (PH) as compared to the general population. PH is a disease characterized by elevated blood pressure in the pulmonary vasculature and is currently with no cure. Experiments with primates found that Nef, an HIV encoded protein secreted in exosomes from HIV+ cells, plays an important role in the development of HIV-PH. HIV-Nef+ exosomes induce endothelial dysfunction, including premature senescence of endothelial colony forming cells (ECFCs). We hypothesize that exosome functions and concentrations in HIV+ patients may vary based on Nef-mutations, and thus potentially define a predictor for the risk of developing PH. Methods: Nef exosomes were isolated from HEK293? cells transfected with molecular constructs containing HIV Nef signature sequences recovered from patients with HIV-PH. The Nef exosomes were then used to treat ECFC. We measured cell proliferation (by MTT assay), apoptosis (cleaved caspase-3 by Western blot), and cell senescence (p16ink4A by flow cytometry) in ECFCs treated with Nef exosomes. LM-10-Nanosight was used to quantify exosome concentrations in patient plasma. Results: ECFC treated with Nef exosomes induced a 30% reduction in cell proliferation (p<0.05, MTT). Western blot analysis demonstrated no significant change in apoptotic signaling, and flow cytometric analysis of p16ink4A showed increased senescence in Nef exosome-treated ECFCs versus mock control. “Nef PH-transfected cells showed that decreased proliferation was dependent on specific mutations of Nef. Conclusion: Expression of Nef in cells results in increased exosome production and treatment of ECFC with these exosomes resulted in decreased proliferation, which inducting the cells towards senescence based on signature sequences in Nef.

Author(s):  
Wang L ◽  
◽  
Shao H ◽  
Che B ◽  
Wang N ◽  
...  

Background and Objectives: Pulmonary Artery Hypertension (PAH) is considered as a malignant tumor in cardiovascular disease. Our previous study found that Calcium-Sensing Receptor (CaSR) is involved in pulmonary vascular remodeling in hypoxic pulmonary hypertension (HPH). However, the relationship of Pulmonary Artery Smooth Muscle Cell (PASMC) phenotypic switching, proliferation, and autophagy in CaSR-related HPH remain unclear. The purpose of this study was to detect the role of a CaSR antagonist, NPS2143, on the vascular remodeling by autophagy modulation under hypoxia. Methods: Hypoxic rat PAH model were simulated in vivo. Meanwhile, mean Pulmonary Artery Pressure (mPAP) was measured while RVI, WT%, and WA% indices were calculated. Immunohistochemistry and Western blot were used to detect phenotypic switching and cell proliferation in pulmonary arteriole. Cell viability was determined in vitro by CCK8 and cell cycle. Cell proliferation, phenotypic switching, autophagy level and PI3K/Akt/mTOR pathways were investigated in human PASMCs through mRNA or Western blot methods. Results: Rats with hypoxic-induced PAH had an increased mPAP, RVI, WT% and WA%. Moreover, expression of CaSR was significantly increased, followed by activation of autophagy (increased LC3b and decreased p62), phenotypic switching of PASMCs (reduced calponin, SMA-a and increased OPN) and pulmonary vascular remodeling. However, NPS2143 weakened these hypoxic effects. The results using hypoxic-induced human PASMCs confirmed that NPS2143 suppressed autophagy and reversed phenotypic switching in vitro by inhibiting PI3K/Akt/mTOR pathways. Conclusions: Our study demonstrates that NPS2143 was conducive to inhibit the proliferation and reverse phenotypic switching of PASMCs by regulating autophagy levels in HPH and vascular remodeling.


2021 ◽  
Vol 12 ◽  
Author(s):  
Fenling Fan ◽  
Yifan Zou ◽  
Yousen Wang ◽  
Peng Zhang ◽  
Xiaoyu Wang ◽  
...  

Background: Similarities in the biology of pulmonary hypertension and cancer suggest that anticancer therapies, such as sanguinarine, may also be effective in treating pulmonary hypertension. This, along with underlying biochemical pathways, is investigated in this study.Methods: Rats were subjected to 4-week hypoxia (or control) with or without sanguinarine treatment. In addition, pulmonary artery smooth muscle cells (PASMCs) were examined after 24–48 h hypoxia (with normoxic controls) and with or without sanguinirine. Pulmonary artery pressures and plasma survivin levels were measured in vivo. Ex vivo tissues were examined histologically with appropriate staining. mRNA and protein levels of survivin, HIF-1α, TGFb1, BMPR2, Smad3, P53, and Kv 1.2, 1.5, 2.1 were determined by real-time PCR and Western blot in PASMCs and distal PAs tissue. PASMC proliferation and changes of TGFb1 and pSmad3 induced by sanguinarine were studied using MTT and Western blot. Electrophysiology for Kv functions was measured by patch-clamp experiments.Results: Four-week hypoxia resulted in an increase in serum survivin and HIF-1α, pulmonary artery pressures, and pulmonary vascular remodeling with hypertrophy. These changes were all decreased by treatment with sanguinarine. Hypoxia induced a rise of proliferation in PASMCs which was prevented by sanguinarine treatment. Hypoxic PASMCs had elevated TGFb1, pSmad3, BMPR2, and HIF1α. These increases were all ameliorated by sanguinarine treatment. Hypoxia treatment resulted in reduced expression and function of Kv 1.2, 1.5, 2.1 channels, and these changes were also modulated by sanguinarine.Conclusion: Sanguinarine is effective in modulating hypoxic pulmonary vascular hypertrophy via the survivin pathway and Kv channels.


2010 ◽  
Vol 298 (6) ◽  
pp. C1414-C1423 ◽  
Author(s):  
Atsushi Oguri ◽  
Tomofumi Tanaka ◽  
Haruko Iida ◽  
Kentarou Meguro ◽  
Haruhito Takano ◽  
...  

Voltage-gated Ca2+ channels (CaV) are ubiquitously expressed in various cell types and play vital roles in regulation of cellular functions including proliferation. However, the molecular identities and function of CaV remained unexplored in preadipocytes. Therefore, whole cell voltage-clamp technique, conventional/quantitative real-time RT-PCR, Western blot, small interfering RNA (siRNA) experiments, and immunohistochemical analysis were applied in mouse primary cultured preadipocytes as well as mouse 3T3-L1 preadipocytes. The effects of CaV blockers on cell proliferation and cell cycle were also investigated. Whole cell recordings of 3T3-L1 preadipocytes showed low-threshold CaV, which could be inhibited by mibefradil, Ni2+ (IC50 of 200 μM), and NNC55-0396. Dominant expression of α1G mRNA was detected among CaV transcripts (α1A–α1I), supported by expression of CaV3.1 protein encoded by α1G gene, with immunohistochemical studies and Western blot analysis. siRNA targeted for α1G markedly inhibited CaV. Dominant expression of α1G mRNA and expression of CaV3.1 protein were also observed in mouse primary cultured preadipocytes. Expression level of α1G mRNA and CaV3.1 protein significantly decreased in differentiated adipocytes. Mibefradil, NNC55-0396, a selective T-type CaV blocker, but not diltiazem, inhibited cell proliferation in response to serum. NNC55-0396 and siRNA targeted for α1G also prevented cell cycle entry/progression. The present study demonstrates that the CaV3.1 T-type Ca2+ channel encoded by α1G subtype is the dominant CaV in mouse preadipocytes and may play a role in regulating preadipocyte proliferation, a key step in adipose tissue development.


2020 ◽  
Author(s):  
Jeongkyung Lee ◽  
Ruya Liu ◽  
Byung S. Kim ◽  
Yiqun Zhang ◽  
Feng Li ◽  
...  

2018 ◽  
Vol 18 (2) ◽  
pp. 210-215 ◽  
Author(s):  
Mona Diab-Assaf ◽  
Josiane Semaan ◽  
Marwan El-Sabban ◽  
Soad K. Al Jaouni ◽  
Rania Azar ◽  
...  

Introduction: Adult T-cell leukemia (ATL) is an aggressive form of malignancy caused by human T- cell lymphotropic virus 1 (HTLV-1). Currently, there is no effective treatment for ATL. Thymoquinone has been reported to have anti-cancer properties. Objective: The aim of this study is to investigatthe effects of TQ on proliferation, apoptosis induction and the underlying mechanism of action in both HTLV-1 positive (C91-PL and HuT-102) and HTLV-1 negative (CEM and Jurkat) malignant T-lymphocytes. Materials and Methods: Cells were incubated with different thymoquinone concentrations for 24h. Cell cytotoxicity was assayed using the CytoTox 96® Non-Radioactive Cytotoxicity Assay Kit. Cell proliferation was determined using CellTiter 96® Non-Radioactive Cell Proliferation. Cell cycle analysis was performed by staining with propidium iodide. Apoptosis was assessed using cell death ELISA kit. The effect of TQ on p53, p21, Bcl-2 protein expression was determined using Western blot analysis while TGF mRNA expression was determined by RT-PCR. Results: At non-cytotoxic concentrations of TQ, it resulted in the inhibition of proliferation in a dose dependent manner. Flow cytometric analysis revealed a shift in the cell cycle distribution to the PreG1 phase which is a marker of apoptosis. Also TQ increase DNA fragmentation. TQ mediated its anti-proliferative effect and apoptosis induction by an up-regulation of TGFβ1, p53 and p21 and a down-regulation of TGF-α and Bcl-2α. Conclusion: Thymoquinone presents antiproliferative and proapoptotic effects in ATL cells. For this reason, further research is required to investigate its possible application in the treatment of ATL.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Jipeng Lu ◽  
Zhongxiong Wu ◽  
Ying Xiong

Abstract Background Osteoarthritis (OA) is a joint disease characterized via destruction of cartilage. Chondrocyte damage is associated with cartilage destruction during OA. Long noncoding RNAs (lncRNAs) are implicated in the regulation of chondrocyte damage in OA progression. This study aims to investigate the role and underlying mechanism of lncRNA homeobox antisense intergenic RNA (HOTAIR) in OA chondrocyte injury. Methods Twenty-three OA patients and healthy controls without OA were recruited. Chondrocytes were isolated from OA cartilage tissues. HOTAIR, microRNA-107 (miR-107) and C-X-C motif chemokine ligand 12 (CXCL12) levels were measured by quantitative real-time polymerase chain reaction and western blot. Cell proliferation, apoptosis and extracellular matrix (ECM) degradation were measured using cell counting kit-8, flow cytometry and western blot. The target interaction was explored by bioinformatics, luciferase reporter and RNA immunoprecipitation assays. Results HOTAIR expression was enhanced, and miR-107 level was reduced in OA cartilage samples. HOTAIR overexpression inhibited cell proliferation, but induced cell apoptosis and ECM degradation in chondrocytes. HOTAIR knockdown caused an opposite effect. MiR-107 was sponged and inhibited via HOTAIR, and knockdown of miR-107 mitigated the effect of HOTAIR silence on chondrocyte injury. CXCL12 was targeted by miR-107. CXCL12 overexpression attenuated the roles of miR-107 overexpression or HOTAIR knockdown in the proliferation, apoptosis and ECM degradation. CXCL12 expression was decreased by HOTAIR silence, and restored by knockdown of miR-107. Conclusion HOTAIR knockdown promoted chondrocyte proliferation, but inhibited cell apoptosis and ECM degradation in OA chondrocytes by regulating the miR-107/CXCL12 axis.


2021 ◽  
Vol 38 (2) ◽  
Author(s):  
Wenqian Zheng ◽  
Jinhui Hu ◽  
Yiming Lv ◽  
Bingjun Bai ◽  
Lina Shan ◽  
...  

AbstractThe use of the anthelmintic drug pyrvinium pamoate (PP) in cancer therapy has been extensively investigated in the last decade. PP has been shown to have an inhibitory effect in colorectal cancer (CRC), but the underlying mechanism remains elusive. We aimed to investigate the antitumor activity and mechanisms of PP in CRC. In the present study, we used CCK-8 assays, colony formation assays, and western blotting to reveal that PP effectively suppressed CRC cell proliferation and the AKT-dependent signaling pathway in a concentration-dependent and time-dependent manner. Flow cytometric analysis and fluorescence microscopy demonstrated that PP increased intracellular reactive oxygen species (ROS) accumulation. We found that the inhibitory effect of PP on cell proliferation and AKT protein expression induced by PP could be partially reversed by N-acetyl-l-cysteine (NAC), an ROS scavenger. In addition, the results also demonstrated that PP inhibited cell migration by modulating epithelial-to-mesenchymal transition (EMT)-related proteins, including E-cadherin and vimentin. In conclusion, our data suggested that PP effectively inhibited cell proliferation through the ROS-mediated AKT-dependent signaling pathway in CRC, further providing evidence for the use of PP as an antitumor agent.


2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
A Kempny ◽  
K Dimopoulos ◽  
A E Fraisse ◽  
G P Diller ◽  
L C Price ◽  
...  

Abstract Background Pulmonary vascular resistance (PVR) is an essential parameter assessed during cardiac catheterization. It is used to confirm pulmonary vascular disease, to assess response to targeted pulmonary hypertension (PH) therapy and to determine the possibility of surgery, such as closure of intra-cardiac shunt or transplantation. While PVR is believed to mainly reflect the properties of the pulmonary vasculature, it is also related to blood viscosity (BV). Objectives We aimed to assess the relationship between measured (mPVR) and viscosity-corrected PVR (cPVR) and its impact on clinical decision-making. Methods We assessed consecutive PH patients undergoing cardiac catheterization. BV was assessed using the Hutton method. Results We included 465 patients (56.6% female, median age 63y). The difference between mPVR and cPVR was highest in patients with abnormal Hb levels (anemic patients: 5.6 [3.4–8.0] vs 7.8Wood Units (WU) [5.1–11.9], P<0.001; patients with raised Hb: 10.8 [6.9–15.4] vs. 7.6WU [4.6–10.8], P<0.001, respectively). Overall, 33.3% patients had a clinically significant (>2.0WU) difference between mPVR and cPVR, and this was more pronounced in those with anemia (52.9%) or raised Hb (77.6%). In patients in the upper quartile for this difference, mPVR and cPVR differed by 4.0WU [3.4–5.2]. Adjustment of PVR required Conclusions We report, herewith, a clinically significant difference between mPVR and cPVR in a third of contemporary patients assessed for PH. This difference is most pronounced in patients with anemia, in whom mPVR significantly underestimates PVR, whereas in most patients with raised Hb, mPVR overestimates it. Our data suggest that routine adjustment for BV is necessary.


Sign in / Sign up

Export Citation Format

Share Document