Abstract
Senescent vascular cells are detected in atherosclerotic lesion, and its involvement in the development of atherosclerosis has been revealed; however, whether and the mechanism by which ...endothelial cell (EC) senescence is causally implicated in atherosclerosis remains unclear. We here investigate a role of EC senescence in atherosclerosis by utilizing EC-specific progeroid mice that overexpress the dominant negative form of telomeric repeat-binding factor 2 under the control of the Tie2 or vascular endothelial cadherin promoter. EC-specific progeria accelerated atherosclerosis in mice with target deletion of ApoE. Mechanistically, senescent ECs were markedly sensitive for inflammation-mediated VCAM-1 induction, leading to enhanced monocyte adhesion. Inhibition of NF-κB signaling abolished the enhanced inflammatory responses in senescent ECs, while NF-κB nuclear translocation in response to TNF-α were similar between young and senescent ECs. We found a higher association of VCAM-1 gene with active histone H3 trimethylated on lysine 4, leading to increased NF-κB accessibility in senescent ECs. Our data revealed that EC cellular senescence causes endothelial hyper-inflammability through epigenetic alteration, which consequently accelerates atherosclerosis. Therefore, EC senescence is a promising therapeutic target for the prevention and/or treatment of atherosclerotic disease in elderly population.
Vascular senescence is thought to play a crucial role in an ageing-associated decline of organ functions; however, whether vascular senescence is causally implicated in age-related disease remains ...unclear. Here we show that endothelial cell (EC) senescence induces metabolic disorders through the senescence-associated secretory phenotype. Senescence-messaging secretomes from senescent ECs induced a senescence-like state and reduced insulin receptor substrate-1 in adipocytes, which thereby impaired insulin signaling. We generated EC-specific progeroid mice that overexpressed the dominant negative form of telomeric repeat-binding factor 2 under the control of the Tie2 promoter. EC-specific progeria impaired systemic metabolic health in mice in association with adipose tissue dysfunction even while consuming normal chow. Notably, shared circulation with EC-specific progeroid mice by parabiosis sufficiently transmitted the metabolic disorders into wild-type recipient mice. Our data provides direct evidence that EC senescence impairs systemic metabolic health, and thus establishes EC senescence as a bona fide risk for age-related metabolic disease.
Cumulative evidence indicates that mitochondrial dysfunction has a role in heart failure progression, but whether mitochondrial quality control mechanisms are involved in the development of cardiac ...dysfunction remains unclear. Here we show that cytosolic p53 impairs autophagic degradation of damaged mitochondria and facilitates mitochondrial dysfunction and heart failure in mice. Prevalence and induction of mitochondrial autophagy is attenuated by senescence or doxorubicin treatment in vitro and in vivo. We show that cytosolic p53 binds to Parkin and disturbs its translocation to damaged mitochondria and their subsequent clearance by mitophagy. p53-deficient mice show less decline of mitochondrial integrity and cardiac functional reserve with increasing age or after treatment with doxorubicin. Furthermore, overexpression of Parkin ameliorates the functional decline in aged hearts, and is accompanied by decreased senescence-associated β-galactosidase activity and proinflammatory phenotypes. Thus, p53-mediated inhibition of mitophagy modulates cardiac dysfunction, raising the possibility that therapeutic activation of mitophagy by inhibiting cytosolic p53 may ameliorate heart failure and symptoms of cardiac ageing.
Pulmonary arterial hypertension is a progressive fatal disease that is characterized by pathological pulmonary artery remodeling, in which endothelial cell dysfunction is critically involved. We ...herein describe a previously unknown role of endothelial angiocrine in pulmonary hypertension. By searching for genes highly expressed in lung microvascular endothelial cells, we identify inhibin-β-A as an angiocrine factor produced by pulmonary capillaries. We find that excess production of inhibin-β-A by endothelial cells impairs the endothelial function in an autocrine manner by functioning as activin-A. Mechanistically, activin-A induces bone morphogenetic protein receptor type 2 internalization and targeting to lysosomes for degradation, resulting in the signal deficiency in endothelial cells. Of note, endothelial cells isolated from the lung of patients with idiopathic pulmonary arterial hypertension show higher inhibin-β-A expression and produce more activin-A compared to endothelial cells isolated from the lung of normal control subjects. When endothelial activin-A-bone morphogenetic protein receptor type 2 link is overdriven in mice, hypoxia-induced pulmonary hypertension was exacerbated, whereas conditional knockout of inhibin-β-A in endothelial cells prevents the progression of pulmonary hypertension. These data collectively indicate a critical role for the dysregulated endothelial activin-A-bone morphogenetic protein receptor type 2 link in the progression of pulmonary hypertension, and thus endothelial inhibin-β-A/activin-A might be a potential pharmacotherapeutic target for the treatment of pulmonary arterial hypertension.
Generally, cancer tissue is palpated as a hard mass. However, the elastic nature of cancer tissue is not well understood. The aim of the present study was to evaluate the clinical utility of ...measuring the elastic modulus (EM) in colorectal cancer tissue. Using a tactile sensor, we measured the EM of 106 surgically resected colorectal cancer tissues. Data on the EM were compared with clinicopathological findings, including stromal features represented by Azan staining and the α‐SMA positive area ratio of the tumor area. Finally, a cDNA microarray profile of the tumors with high EM were compared with the findings of tumors with low EM. A higher EM in tumors was associated with pathological T, N, and M‐stage tumors (P < 0.001, P = 0.001 and P = 0.011, respectively). Patients with high EM tumors had shorter disease‐free survival than had patients with low EM. The EM showed strongly positive correlation with the Azan staining positive area ratio (r = 0.908) and the α‐SMA positive area ratio (r = 0.921). Finally, the cDNA microarray data of the tumors with high EM revealed a distinct gene expression profile compared with data from those tumors with low EM. The assessment of the elasticity of colorectal cancer tissue may allow a more accurate clinical stage and prognosis estimation. The distinct phenotypical features of the high EM tumors and their strong association with stromal features suggest the existence of a biological mechanism involved in this phenomenon that may contribute to future therapy.
Cancer tissue is palpated as a hard tissue, but the nature of cancer tissue elasticity is not known. We investigated the elastic modulus (EM) of resected colorectal cancer specimens using an objective and quantitative approach, and found strong association with TNM classification and disease‐free survival, which suggested future clinical implications. Finally, we are the first to elucidate the elasticity‐dependent phenotypical features of colorectal cancer tissue using global gene expression analysis.
•A temperature-responsive SPE system for the purification of proteins was developed.•Targeted proteins were retained on the hydrogel surface at 40 °C and eluted at 4 °C.•Lysozyme was successfully ...separated from ovalbumin without loss of activity.•Rituximab, a monoclonal antibody, was purified from hybridoma cell culture media.
Recently, the importance of biopharmaceuticals in medical treatments has been increasing, and effective protein purification methods are strongly required for their production. In the present study, a temperature-responsive solid-phase extraction (SPE) column was developed for the purification of proteins without affecting their bioactivity. A temperature-responsive polymer hydrogel-modified stationary phase was prepared by coating aminopropyl silica beads (average diameter, 40–64 μm) with poly(N-isopropylacrylamide) (PNIPAAm)-based thermoresponsive hydrogels. n-Butyl methacrylate and acrylic acid were copolymerized with PNIPAAm as hydrophobic and anionic monomers, respectively. Using these temperature-responsive SPE columns, targeted proteins were retained on the thermoresponsive hydrogel at 40 °C through hydrophobic and electrostatic interactions. After the temperature was reduced from 40 °C to 4 °C, the retained proteins were successfully eluted from the column. Using the temperature-responsive SPE system, lysozyme was successfully separated from ovalbumin without any loss in bioactivity (99.7 ± 0.1%). Rituximab, a monoclonal antibody, was also purified from BSA or hybridoma cell culture medium using the prepared SPE column. Denaturation of rituximab was not observed in the rituximab fraction eluted from the SPE column. These results demonstrate that temperature-responsive polymer-based SPE can be applied in biomedical purifications, while maintaining the biological activity of the proteins.
Background:The effect of treatment with paclitaxel-containing devices (PTXD) on mortality in patients with peripheral artery disease remains controversial.Methods and Results:An independent ...patient-level meta-analysis of 12 clinical trials (1,389 PTXD patients and 1,192 non-PTXD patients) was conducted. This study included 7 pivotal trials and 5 post-marketing surveillance studies on endovascular treatment for femoropopliteal artery by 6 companies. The primary endpoint was all-cause death, and 5-year cumulative mortality was estimated by a Kaplan-Meier curve. Cox proportional hazard model was used to calculate the hazard ratio (HR) and confidential interval (CI). During the median follow up of 3.0 years, 459 patients died. The cumulative 5-year mortality for the entire cohort was significantly lower in the PTXD than in the non-PTXD group (24.4% vs. 27.4%, respectively; HR, 0.81; 95% CI, 0.67–0.97; P=0.023), but this difference was no longer significant after adjustment for relevant covariates (HR, 1.01; 95% CI, 0.39–2.58; P=0.987). The Cox proportional hazard model revealed that sex, hyperlipidemia, Type 2 diabetes, hemodialysis, Rutherford category, and age above 75 years were significantly associated with 5-year mortality, but treatment with PTXD was not.Conclusions:This large individual meta-analysis of patients with femoropopliteal artery disease found that the use of PTXD does not have a negative effect on 5-year mortality.
Background
Peritoneal recurrence (PR) of colorectal cancer is a poor prognostic factor but may be treatable by curative resection. We investigated the efficacy of this treatment and identified risk ...factors for postoperative recurrence.
Methods
The subjects were patients who underwent radical surgery for colorectal cancer between January 2006 and March 2014. Those with PR were retrospectively reviewed. Prognostic factors for overall survival (OS) and risk factors for postoperative recurrence were identified.
Results
Among 2256 patients, 66 had PR (2.9%). Surgical resection of PR was performed in 41 patients. Curative resection was achieved macroscopically in 38 cases without diffuse metastases in the peritoneum distant from the primary tumor and with a peritoneal cancer index < 10. In multivariate analysis, curative resection was a significant prognostic factor hazard ratio (HR) 0.198 for better 5-year OS compared with cases without curative resection (68.7% vs. 6.3%,
P
< 0.001). In 28 cases with concurrent metastasis, curative resection significantly improved 5-year OS compared with no curative resection (78.7% vs. 0%,
P
= 0.008). In the 38 patients with curative resection, the 3-year recurrence-free survival rate was 21.4%. In multivariate analysis, concurrent metastasis was a significant risk factor HR 3.394 for postoperative recurrence, and cases with concurrent metastasis more frequently had recurrence within 2 years after curative resection.
Conclusions
Curative resection improved the prognosis in patients with limited and resectable PR of colorectal cancer with or without concurrent metastasis. However, recurrence after curative resection was common and concurrent metastasis was a risk factor for this recurrence.
Aging is closely associated with the increased morbidity and mortality of ischemic cardiovascular disease, at least partially through impaired angiogenic capacity. Endothelial cells (ECs) play a ...crucial role in angiogenesis, and their angiogenic capacity declines during aging. Spermidine is a naturally occurring polyamine, and its dietary supplementation has exhibited distinct anti-aging and healthy lifespan-extending effects in various species such as yeast, worms, flies, and mice. Here, we explore the effects of spermidine supplementation on the age-related decline in angiogenesis both in vitro and in vivo. Intracellular polyamine contents were reduced in replicative senescent ECs, which were subsequently recovered by spermidine supplementation. Our findings reveal that spermidine supplementation improved the declined angiogenic capacity of senescent ECs, including migration and tube-formation, without affecting the senescence phenotypes. Mechanistically, spermidine enhanced both autophagy and mitophagy, and improved mitochondrial quality in senescent ECs. Ischemia-induced neovascularization was assessed using the hind-limb ischemia model in mice. Limb blood flow recovery and neovascularization in the ischemic muscle were considerably impaired in aged mice compared to young ones. Of note, dietary spermidine significantly enhanced ischemia-induced angiogenesis, and improved the blood flow recovery in the ischemic limb, especially in aged mice. Our results reveal novel proangiogenic functions of spermidine, suggesting its therapeutic potential against ischemic disease.
Mitochondrial compromise is a fundamental contributor to pancreatic β-cell failure in diabetes. Previous studies have demonstrated a broader role for tumor suppressor p53 that extends to the ...modulation of mitochondrial homeostasis. However, the role of islet p53 in glucose homeostasis has not yet been evaluated. Here we show that p53 deficiency protects against the development of diabetes in streptozotocin (STZ)-induced type 1 and db/db mouse models of type 2 diabetes. Glucolipotoxicity stimulates NADPH oxidase via receptor for advanced-glycation end products and Toll-like receptor 4. This oxidative stress induces the accumulation of p53 in the cytosolic compartment of pancreatic β-cells in concert with endoplasmic reticulum stress. Cytosolic p53 disturbs the process of mitophagy through an inhibitory interaction with Parkin and induces mitochondrial dysfunction. The occurrence of mitophagy is maintained in STZ-treated p53 ⁻/⁻ mice that exhibit preserved glucose oxidation capacity and subsequent insulin secretion signaling, leading to better glucose tolerance. These protective effects are not observed when Parkin is deleted. Furthermore, pifithrin-α, a specific inhibitor of p53, ameliorates mitochondrial dysfunction and glucose intolerance in both STZ-treated and db/db mice. Thus, an intervention with cytosolic p53 for a mitophagy deficiency may be a therapeutic strategy for the prevention and treatment of diabetes.
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