Prevention of atherosclerosis by the mTOR inhibitor everolimus in LDLR-/- mice despite severe hypercholesterolemia

Navigating the Maze of Kinases: CaMK-like Family Protein Kinases and Their Role in Atherosclerosis

Circulating low-density lipoprotein (LDL) levels are a major risk factor for cardiovascular diseases (CVD), and even though current treatment strategies focusing on lowering lipid levels are effective, CVD remains the primary cause of death worldwide. Atherosclerosis is the major cause of CVD and is a chronic inflammatory condition in which various cell types and protein kinases play a crucial role. However, the underlying mechanisms of atherosclerosis are not entirely understood yet. Notably, protein kinases are highly druggable targets and represent, therefore, a novel way to target atherosclerosis. In this review, the potential role of the calcium/calmodulin-dependent protein kinase-like (CaMKL) family and its role in atherosclerosis will be discussed. This family consists of 12 subfamilies, among which are the well-described and conserved liver kinase B1 (LKB1) and 5' adenosine monophosphate-activated protein kinase (AMPK) subfamilies. Interestingly, LKB1 plays a key role and is considered a master kinase within the CaMKL family. It has been shown that LKB1 signaling leads to atheroprotective effects, while, for example, members of the microtubule affinity-regulating kinase (MARK) subfamily have been described to aggravate atherosclerosis development. These observations highlight the importance of studying kinases and their signaling pathways in atherosclerosis, bringing us a step closer to unraveling the underlying mechanisms of atherosclerosis.

Cholesterol trafficking, lysosomal function, and atherosclerosis

Despite years of study and major research advances over the past 50 years, atherosclerotic diseases continue to rank as the leading global cause of death. Accumulation of cholesterol within the vascular wall remains the main problem and represents one of the early steps in the development of atherosclerotic lesions. There is a complex relationship between vesicular cholesterol transport and atherosclerosis, and abnormalities in cholesterol trafficking can contribute to the development and progression of the lesions. The dysregulation of vesicular cholesterol transport and lysosomal function fosters the buildup of cholesterol within various intracytoplasmic compartments, including lysosomes and lipid droplets. This, in turn, promotes the hallmark formation of foam cells, a defining feature of early atherosclerosis. Multiple cellular processes, encompassing endocytosis, exocytosis, intracellular trafficking, and autophagy, play crucial roles in influencing foam cell formation and atherosclerotic plaque stability. In this review, we highlight recent advances in the understanding of the intricate mechanisms of vesicular cholesterol transport and its relationship with atherosclerosis and discuss the importance of understanding these mechanisms in developing strategies to prevent or treat this prevalent cardiovascular disease.

Hutchinson-Gilford progeria syndrome: Cardiovascular manifestations and treatment

Hutchinson-Gilford progeria syndrome (HGPS), also known as hereditary progeria syndrome, is caused by mutations in the LMNA gene and the expression of progerin, which causes accelerated aging and premature death, with most patients dying of heart failure or other cardiovascular complications in their teens. HGPS patients are able to exhibit cardiovascular phenotypes similar to physiological aging, such as extensive atherosclerosis, smooth muscle cell loss, vascular lesions, and electrical and functional abnormalities of the heart. It also excludes the traditional risk causative factors of cardiovascular disease, making HGPS a new model for studying aging-related cardiovascular disease. Here, we analyzed the pathogenesis and pathophysiological characteristics of HGPS and the relationship between HGPS and cardiovascular disease, provided insight into the molecular mechanisms of cardiovascular disease pathogenesis in HGPS patients and treatment strategies for this disease. Moreover, we summarize the disease models used in HGPS studies to improve our understanding of the pathological mechanisms of cardiovascular aging in HGPS patients.

Are menopause, aging and prostate cancer diseases?

There is no doubt that prostate cancer is a disease. Then, according to hyperfunction theory, menopause is also a disease. Like all age-related diseases, it is a natural process, but is also purely harmful, aimless and unintended by nature. But exactly because these diseases (menopause, prostate enlargement, obesity, atherosclerosis, hypertension, diabetes, presbyopia and thousands of others) are partially quasi-programmed, they can be delayed by slowing aging. Is aging a disease? Aging is a quasi-programmed disease that is partially treatable by rapamycin. On the other hand, aging is an abstraction, a sum of all quasi-programmed diseases and processes. In analogy, the zoo consists of animals and does not exist without animals, but the zoo is not an animal.

Natural compounds from botanical drugs targeting mTOR signaling pathway as promising therapeutics for atherosclerosis: A review

Atherosclerosis (AS) is a chronic inflammatory disease that is a major cause of cardiovascular diseases (CVDs), including coronary artery disease, hypertension, myocardial infarction, and heart failure. Hence, the mechanisms of AS are still being explored. A growing compendium of evidence supports that the activity of the mechanistic/mammalian target of rapamycin (mTOR) is highly correlated with the risk of AS. The mTOR signaling pathway contributes to AS progression by regulating autophagy, cell senescence, immune response, and lipid metabolism. Various botanical drugs and their functional compounds have been found to exert anti- AS effects by modulating the activity of the mTOR signaling pathway. In this review, we summarize the pathogenesis of AS based on the mTOR signaling pathway from the aspects of immune response, autophagy, cell senescence, and lipid metabolism, and comb the recent advances in natural compounds from botanical drugs to inhibit the mTOR signaling pathway and delay AS development. This review will provide a new perspective on the mechanisms and precision treatments of AS.

Cardiovascular effects of immunosuppression agents

Immunosuppressive medications are widely used to treat patients with neoplasms, autoimmune conditions and solid organ transplants. Key drug classes, namely calcineurin inhibitors, mammalian target of rapamycin (mTOR) inhibitors, and purine synthesis inhibitors, have direct effects on the structure and function of the heart and vascular system. In the heart, immunosuppressive agents modulate cardiac hypertrophy, mitochondrial function, and arrhythmia risk, while in vasculature, they influence vessel remodeling, circulating lipids, and blood pressure. The aim of this review is to present the preclinical and clinical literature examining the cardiovascular effects of immunosuppressive agents, with a specific focus on cyclosporine, tacrolimus, sirolimus, everolimus, mycophenolate, and azathioprine.

A nanotherapy responsive to the inflammatory microenvironment for the dual-targeted treatment of atherosclerosis

Atherosclerosis remains the main cause of death and disability, as well as a leading cause of coronary arterial disease. Inflammation is one of the pathogenic factors of arteriosclerosis; however, the current treatments based on lowering the level of inflammation in the plaque tissue of patients with atherosclerosis are not clinically used. Herein, we hypothesize that α_vβ₃ receptor affinity and low pH sensitivity may be regarded as a valid therapeutic strategy for targeting sites of atherosclerosis according to the microenvironments of inflammation. To prove this tentative hypothesis, an acid-labile material polyketal named PK3 was synthesized, and the cRGDfc peptide was used to modify nanoparticles composed of poly(lactide-co-glycolide) (PLGA), lecithin, and PK3, loaded with the anti-atherosclerotic drug rapamycin (RAP). The nanoparticles were prepared using an O/W method and then characterized, which showed an appropriate particle size and fulfilling responsive behaviors. In vitro release studies and stability tests showed that these nanoparticles can be effectively internalized by human umbilical vein endothelial cells (HUVEC), and also show a good in vitro anti-inflammatory effect. After intravenous (i.v.) injection, RGD targeted by pH-responsive nanotherapy (RAP-Nps-RGD) may be accumulated at the plaque site in ApoE^-/- mice with atherosclerosis and can effectively attenuate plaque progression compared to other formulations. Moreover, its good safety profile and biocompatibility have been revealed in both in vitro and in vivo estimations. Accordingly, the prospect of nanoparticles responsive to the inflammatory microenvironment for preventing atherosclerotic through inflammation modulation provides great feasibility for the administration of alternate drug molecules to inflamed sites to slow down the process of arteriosclerosis.

Sex Differences in Lipid Metabolism: Implications for Systemic Lupus Erythematosus and Cardiovascular Disease Risk

It is known that healthy women during childbearing years have a lower risk of cardiovascular disease (CVD) and coronary heart disease compared to age matched men. Various traditional risk factors have been shown to confer differential CVD susceptibilities by sex. Atherosclerosis is a major cause of CVD and mortality and sex differences in CVD risk could be due to reduced atherogenic low and very low-density lipoproteins (LDL and VLDL) and increased atheroprotective high density lipoproteins (HDLs) in women. In contrast, patients with systemic lupus erythematosus (SLE), a chronic inflammatory disease that predominately affects women, have an increased atherosclerotic and CVD risk. This increased CVD risk is largely associated with dyslipidaemia, the imbalance of atherogenic and atheroprotective lipoproteins, a conventional CVD risk factor. In many women with SLE, dyslipidaemia is characterised by elevated LDL and reduced HDL, eradicating the sex-specific CVD protection observed in healthy women compared to men. This review will explore this paradox, reporting what is known regarding sex differences in lipid metabolism and CVD risk in the healthy population and transgender individuals undergoing cross-sex hormone therapy, and provide evidence for how these differences may be compromised in an autoimmune inflammatory disease setting. This could lead to better understanding of mechanistic changes in lipid metabolism driving the increased CVD risk by sex and in autoimmunity and highlight potential therapeutic targets to help reduce this risk.

Programmed cell death in atherosclerosis and vascular calcification

The concept of cell death has been expanded beyond apoptosis and necrosis to additional forms, including necroptosis, pyroptosis, autophagy, and ferroptosis. These cell death modalities play a critical role in all aspects of life, which are noteworthy for their diverse roles in diseases. Atherosclerosis (AS) and vascular calcification (VC) are major causes for the high morbidity and mortality of cardiovascular disease. Despite considerable advances in understanding the signaling pathways associated with AS and VC, the exact molecular basis remains obscure. In the article, we review the molecular mechanisms that mediate cell death and its implications for AS and VC. A better understanding of the mechanisms underlying cell death in AS and VC may drive the development of promising therapeutic strategies.

Resveratrol protects against atherosclerosis by downregulating the PI3K/AKT/mTOR signaling pathway in atherosclerosis model mice

Atherosclerosis is a cardiovascular disease, which is characterized by the interaction between carbohydrates, lipids, cells and various other molecules and genetic factors. Previous studies have demonstrated that resveratrol (RV) served protective roles in numerous types of human disease by regulating different signaling pathways. The aim of the present study was to investigate the therapeutic effects of RV and analyze the potential RV-mediated mechanism in umbilical vein endothelial cells (UVECS) in atherosclerosis model mice. Reverse transcription-quantitative PCR, western blotting and immunohistochemistry were used to analyze the therapeutic effects of RV both in vitro and in vivo. The results demonstrated that total cholesterol, triglycerides, low-density lipoprotein cholesterin and high-density lipoprotein cholesterin levels were significantly decreased in the RV group compared with the control group. RV demonstrated significant anti-atherosclerotic activity, which was determined through the atherogenic index, 3-hydroxy-3-methyl-glutaryl-Coa (HMG-CoA) reductase activity and marker enzymes, such as lactate dehydrogenase, creatine phosphokinase, aspartate transaminase, alanine transaminase and alkaline phosphatase. It was also observed that RV treatment significantly decreased the area of the arteriosclerotic lesion in the RV group compared with the control, as well as significantly decreasing the expression levels of matrix metalloproteinase-9 and CD40 ligand (CD40L) in arterial lesion tissue compared with the control group. Serum expression levels of tumor necrosis factor-α and C-reactive protein were also significantly decreased by RV treatment compared with the control group. Furthermore, RV treatment significantly decreased the expression levels of PI3K, AKT and mTOR in UVECS in vitro. In conclusion, these results suggested that the anti-atherosclerotic activity of RV may be due to its modulatory activity over the PI3K/AKT/mTOR signaling pathway. These findings suggested a potential novel treatment option for patients with atherosclerosis.

GALNT4 primes monocytes adhesion and transmigration by regulating O-Glycosylation of PSGL-1 in atherosclerosis

Atherosclerosis is a major underlying cause of cardiovascular disease. Genome wide association studies have predicted that GalNAc-T4 (GALNT4), which responsible for initiating step of mucin-type O-glycosylation, plays a causal role in the susceptibility to cardiovascular diseases, whereas the precise mechanism remains obscure. Thus, we sought to determine the role and mechanism of GALNT4 in atherosclerosis. Firstly, we found the expression of GALNT4 and protein O-glycosylation were both increased in plaque as atherosclerosis progressed in ApoE-/- mice by immunohistochemistry. And the expression of GALNT4 was also increased in human monocytes treated with ACS (acute coronary syndrome) sera and subjected to LPS and ox-LDL in vitro. Moreover, silencing expression of GALNT4 by shRNA lentivirus alleviated atherosclerotic plaque formation and monocyte/macrophage infiltration in ApoE-/- mice. Functional investigations demonstrate that GALNT4 knockdown inhibited P-selectin-induced activation of β2 integrin on the surface of monocytes, decreased monocytes adhesion under flow condition with P-selectin stimulation, as well as suppressed monocytes transmigration triggered by monocyte chemotactic protein- 1(MCP-1). In contrast, GALNT4 overexpression enhanced monocytes adhesion and transmigration. Furthermore, Vicia Villosa Lectin (VVL) pull down and PSGL-1 immunoprecipitation assays showed that GALNT4 overexpression increased O-Glycosylation of PSGL-1 and P-selectin induce phosphorylation of Akt/mTOR and IκBα/NFκB on monocytes. Conversely, knockdown of GALNT4 decreased VVL binding and attenuated the activation of Akt/mTOR and IκBα/NFκB. Additionally, mTOR inhibitor rapamycin blocked these effects of GALNT4 overexpression on monocytes. Collectively, GALNT4 catalyzed PSGL-1 O-glycosylation that involved in P-selectin induced monocytes adhesion and transmigration via Akt/mTOR and NFκB pathway. Thus, GALNT4 may be a potential therapeutic target for atherosclerosis.

The Function, Regulation and Mechanism of Programmed Cell Death of Macrophages in Atherosclerosis

Atherosclerosis is a chronic progressive inflammatory vascular disease, which is an important pathological basis for inducing a variety of cardio-cerebrovascular diseases. As a kind of inflammatory cells, macrophages are the most abundant immune cells in atherosclerotic plaques and participate in the whole process of atherosclerosis and are the most abundant immune cells in atherosclerotic plaques. Recent studies have shown that programmed cell death plays a critical role in the progression of many diseases. At present, it is generally believed that the programmed death of macrophages can affect the development and stability of atherosclerotic vulnerable plaques, and the intervention of macrophage death may become the target of atherosclerotic therapy. This article reviews the role of macrophage programmed cell death in the progression of atherosclerosis and the latest therapeutic strategies targeting macrophage death within plaques.

Modulating mTOR Signaling as a Promising Therapeutic Strategy for Atherosclerosis

For more than a decade, atherosclerosis has been one of the leading causes of death in developed countries. The issue of treatment and prevention of the disease is especially acute. Despite the huge amount of basic and clinical research, a significant number of gaps remain in our understanding of the pathogenesis of atherosclerosis, and only their closure will bring us closer to understanding the causes of the disease at the cellular and molecular levels and, accordingly, to the development of an effective treatment. One of the seemingly well-studied elements of atherogenesis is the mTOR signaling pathway. However, more and more new details are still being clarified. Therapeutic strategies associated with rapamycin have worked well in a number of different diseases, and there is every reason to believe that targeting components of the mTOR pathway may pay off in atherosclerosis as well.

Left Ventricular Hypertrophy in Diabetic Cardiomyopathy: A Target for Intervention

Heart failure is an important manifestation of diabetic heart disease. Before the development of symptomatic heart failure, as much as 50% of patients with type 2 diabetes mellitus (T2DM) develop asymptomatic left ventricular dysfunction including left ventricular hypertrophy (LVH). Left ventricular hypertrophy (LVH) is highly prevalent in patients with T2DM and is a strong predictor of adverse cardiovascular outcomes including heart failure. Importantly regression of LVH with antihypertensive treatment especially renin angiotensin system blockers reduces cardiovascular morbidity and mortality. However, this approach is only partially effective since LVH persists in 20% of patients with hypertension who attain target blood pressure, implicating the role of other potential mechanisms in the development of LVH. Moreover, the pathophysiology of LVH in T2DM remains unclear and is not fully explained by the hyperglycemia-associated cellular alterations. There is a growing body of evidence that supports the role of inflammation, oxidative stress, AMP-activated kinase (AMPK) and insulin resistance in mediating the development of LVH. The recognition of asymptomatic LVH may offer an opportune target for intervention with cardio-protective therapy in these at-risk patients. In this article, we provide a review of some of the key clinical studies that evaluated the effects of allopurinol, SGLT2 inhibitor and metformin in regressing LVH in patients with and without T2DM.

The role and transformative potential of IL-19 in atherosclerosis

Atherosclerotic cardiovascular disease is the leading cause of death worldwide. Traditionally, IL-19 was thought to be expressed in only immune cells, but studies revealed that IL-19 is also expressed in multiple atherosclerotic plaque cell types, but not normal arteries, in humans and mice. IL-19 reduces the development of atherosclerosis via multiple mechanisms, including balancing cholesterol metabolism; enhancing Th2 immune cell polarization; reducing the inflammatory response; and reducing the proliferation, migration and chemotaxis of vascular smooth muscle cells (VSMCs). Clinical and/or animal studies have primarily aimed to achieve regression and/or stabilization of atherosclerotic plaques, with regression in particular indicating a very good drug response. Most antiatherosclerotic drugs in current clinical use, including atorvastatin and alirocumab, target hyperlipidemia. Several other drugs have also been investigated in clinical trials as anti-inflammatory agents; the development of some of these agents has been terminated (canakinumab, darapladib, varespladib, losmapimod, atreleuton, setileuton, PF-04191834, veliflapon, and methotrexate), but others remain in development (ziltivekimab, tocilizumab, Somalix, IFM-2427, anakinra, mesenchymal stem cells (MSCs), colchicine, everolimus, allopurinol, and montelukast). Most of the tested drugs have shown a limited ability to reverse atherosclerosis in animal studies. Interestingly, recombinant IL-19 (rIL-19) was shown to reduce atherosclerosis development in a time- and dose-dependent manner. A low dose of rIL-19 (1 ng/g/day) reduced aortic arch and root plaque areas by 70.1% and 32.1%, respectively, in LDLR^-/- mice. At 10 ng/g/day, rIL-19 completely eliminated atherosclerotic plaques. There were no sex differences in the effects of rIL-19 on atherosclerotic mice. Thus, low-dose rIL-19 is an effective antiatherosclerotic agent, in addition to its efficacy in intimal hyperplasia, spinal cord injury, stroke, and multiple sclerosis. We propose that IL-19 is a promising biomarker and target for the diagnosis and treatment of atherosclerosis. This review considers the role and mechanism of action of IL-19 in atherosclerosis and discusses whether IL-19 is a potential therapeutic target for this condition.

Effect of rapamycin on aging and age-related diseases-past and future

In 2009, rapamycin was reported to increase the lifespan of mice when implemented later in life. This observation resulted in a sea-change in how researchers viewed aging. This was the first evidence that a pharmacological agent could have an impact on aging when administered later in life, i.e., an intervention that did not have to be implemented early in life before the negative impact of aging. Over the past decade, there has been an explosion in the number of reports studying the effect of rapamycin on various diseases, physiological functions, and biochemical processes in mice. In this review, we focus on those areas in which there is strong evidence for rapamycin's effect on aging and age-related diseases in mice, e.g., lifespan, cardiac disease/function, central nervous system, immune system, and cell senescence. We conclude that it is time that pre-clinical studies be focused on taking rapamycin to the clinic, e.g., as a potential treatment for Alzheimer's disease.

Role of lysosomes in physiological activities, diseases, and therapy

Long known as digestive organelles, lysosomes have now emerged as multifaceted centers responsible for degradation, nutrient sensing, and immunity. Growing evidence also implicates role of lysosome-related mechanisms in pathologic process. In this review, we discuss physiological function of lysosomes and, more importantly, how the homeostasis of lysosomes is disrupted in several diseases, including atherosclerosis, neurodegenerative diseases, autoimmune disorders, pancreatitis, lysosomal storage disorders, and malignant tumors. In atherosclerosis and Gaucher disease, dysfunction of lysosomes changes cytokine secretion from macrophages, partially through inflammasome activation. In neurodegenerative diseases, defect autophagy facilitates accumulation of toxic protein and dysfunctional organelles leading to neuron death. Lysosomal dysfunction has been demonstrated in pathology of pancreatitis. Abnormal autophagy activation or inhibition has been revealed in autoimmune disorders. In tumor microenvironment, malignant phenotypes, including tumorigenesis, growth regulation, invasion, drug resistance, and radiotherapy resistance, of tumor cells and behaviors of tumor-associated macrophages, fibroblasts, dendritic cells, and T cells are also mediated by lysosomes. Based on these findings, a series of therapeutic methods targeting lysosomal proteins and processes have been developed from bench to bedside. In a word, present researches corroborate lysosomes to be pivotal organelles for understanding pathology of atherosclerosis, neurodegenerative diseases, autoimmune disorders, pancreatitis, and lysosomal storage disorders, and malignant tumors and developing novel therapeutic strategies.

Lysosome (Dys)function in Atherosclerosis-A Big Weight on the Shoulders of a Small Organelle

Atherosclerosis is a progressive insidious chronic disease that underlies most of the cardiovascular pathologies, including myocardial infarction and ischemic stroke. The malfunctioning of the lysosomal compartment has a central role in the etiology and pathogenesis of atherosclerosis. Lysosomes are the degradative organelles of mammalian cells and process endogenous and exogenous substrates in a very efficient manner. Dysfunction of these organelles and consequent inefficient degradation of modified low-density lipoproteins (LDL) and apoptotic cells in atherosclerotic lesions have, therefore, numerous deleterious consequences for cellular homeostasis and disease progression. Lysosome dysfunction has been mostly studied in the context of the inherited lysosomal storage disorders (LSDs). However, over the last years it has become increasingly evident that the consequences of this phenomenon are more far-reaching, also influencing the progression of multiple acquired human pathologies, such as neurodegenerative diseases, cancer, and cardiovascular diseases (CVDs). During the formation of atherosclerotic plaques, the lysosomal compartment of the various cells constituting the arterial wall is under severe stress, due to the tremendous amounts of lipoproteins being processed by these cells. The uncontrolled uptake of modified lipoproteins by arterial phagocytic cells, namely macrophages and vascular smooth muscle cells (VSMCs), is the initial step that triggers the pathogenic cascade culminating in the formation of atheroma. These cells become pathogenic "foam cells," which are characterized by dysfunctional lipid-laden lysosomes. Here, we summarize the current knowledge regarding the origin and impact of the malfunctioning of the lysosomal compartment in plaque cells. We further analyze how the field of LSD research may contribute with some insights to the study of CVDs, particularly how therapeutic approaches that target the lysosomes in LSDs could be applied to hamper atherosclerosis progression and associated mortality.

Chronic everolimus treatment of high-fat diet mice leads to a reduction in obesity but impaired glucose tolerance

Everolimus, which inhibits mTOR kinase activity and is clinically used in graft rejection treatment, may have a two‐sided influence on metabolic syndrome; its role in obesity and hyperglycemic in animals and humans, however, has been explored insufficiently. This study further determined how continual everolimus treatment affects glucose homeostasis and body weight control in C57BL6/J mice with obesity. An obesity mouse model was developed by administering a high‐fat diet (HFD) to C57BL6/J mice over 12 weeks. The experimental group, while continuing their HFD consumption, were administered everolimus daily for 8 weeks. Metabolic parameters, glucose tolerance, fatty liver score, endocrine profile, insulin sensitivity index (ISI), insulin resistance (IR) index, and Akt phosphorylation, GLUT4, TNF‐α, and IL‐1 levels were measured in vivo. Compared with the control group, the everolimus group gained less body weight and had smaller adipocytes and lower fat pad weight; triglyceride (serum and hepatic), patatin‐like phospholipase domain‐containing 3, and fatty acid synthase levels; fatty liver scores; and glucose tolerance test values—all despite consuming more food. However, the everolimus group exhibited decreased ISI and muscle Akt phosphorylation and GLUT4 expression as well as impaired glucose tolerance and serum TNF‐α and IL‐1β levels—even when insulin levels were high. In conclusion, continual everolimus treatment may lead to diabetes with glucose intolerance and IR.

Mtor inhibitors associated with higher cardiovascular adverse events-A large population database analysis

There are limited real-world data available regarding adverse events (AEs) of immunosuppressants. We utilized the FDA Adverse Event Reporting System (FAERS) database from 2004 to 2018 to perform a retrospective database analysis. We analyzed AE reports due to the individual agents tacrolimus, sirolimus, or everolimus and compared reporting odds ratios of the mTOR inhibitors to tacrolimus. The mTOR inhibitors arm had 1282 reports with 4176 AEs, while the tacrolimus arm had a total of 7587 reports with 20 940 individual AEs. mTOR inhibitors had significantly higher incidences of cardiovascular (ROR 1.95, 95% CI 1.70, 2.23), dermatologic (ROR 1.34, 95% CI 1.04, 1.73), endocrine (ROR 1.52, 95% CI 1.26, 1.82), gastrointestinal (ROR 1.15, 95% CI 1.01, 1.30), infectious disease (ROR 1.35, 95% 1.20, 1.52), musculoskeletal (ROR 1.39, 95% CI 1.13, 1.70), pulmonary (ROR 3.46, 95% 2.97, 4.03), renal (ROR 1.27, 95% CI 1.10, 1.46), and vascular AEs (ROR 3.10, 95% CI 2.14, 4.49). Across every organ type, mTOR inhibitors had greater cardiovascular AEs compared to tacrolimus, specifically in arteriosclerosis, heart failure, hypotension, tachycardia, chest pain, edema, and pericardial disorders. mTOR inhibitors may be associated with higher cardiovascular AEs. Further investigation is required to determine the potential mechanism of this effect.

Visceral adiposity index and cervical arterial atherosclerosis in northeast China: a population based cross-sectional survey

BACKGROUND AND PURPOSE

The burden of cervical arterial atherosclerosis, which is an important risk factor of stroke, is huge in China. The visceral adiposity index (VAI) is a convenient index that is related to a series of metabolic abnormalities and a variety of diseases, including cerebrovascular diseases. This study aimed to explore the relationship between VAI and cervical arterial atherosclerosis.

METHODS

This cross-sectional study used the multistage stratified random cluster sampling method to acquire a representative sample of residents aged ≥40 in the general population of northeast China. All participants completed a detailed questionnaire and provided blood samples. Cervical vascular ultrasound was performed by experienced ultrasound doctors. VAI was calculated by a well-established formula and analyzed by quartiles (Q1-Q4).

RESULTS

A total of 3688 people aged ≥40 years who underwent cervical arterial ultrasound were finally included, amongst whom 3.2% had increased intima-media thickness (IMT), 48.6% had carotid plaque and 4.0% had cervical artery stenosis (CAS). After adjusting for several parameters, little statistical significance was found between VAI and increased IMT; compared with the VAI-Q1 group, the VAI-Q2, VAI-Q3 and VAI-Q4 groups were more likely to have CAS [odds ratio (OR) 2.01, 95% confidence interval (CI) 1.17-3.43; OR 1.82, 95% CI 1.05-3.15; OR 1.79, 95% CI 1.03-3.12] and the VAI-Q3 and VAI-Q4 groups were at greater risk of carotid plaque (OR 1.30, 95% CI 1.05-1.62; OR 1.34, 95% CI 1.07-1.67).

CONCLUSIONS

The VAI was related to carotid plaque and CAS in the general population that is older than 40 years.

Pharmacotherapy to gene editing: potential therapeutic approaches for Hutchinson-Gilford progeria syndrome

Hutchinson-Gilford progeria syndrome (HGPS), commonly called progeria, is an extremely rare disorder that affects only one child per four million births. It is characterized by accelerated aging in affected individuals leading to premature death at an average age of 14.5 years due to cardiovascular complications. The main cause of HGPS is a sporadic autosomal dominant point mutation in LMNA gene resulting in differently spliced lamin A protein known as progerin. Accumulation of progerin under nuclear lamina and activation of its downstream effectors cause perturbation in cellular morphology and physiology which leads to a systemic disorder that mainly impairs the cardiovascular system, bones, skin, and overall growth. Till now, no cure has been found for this catastrophic disorder; however, several therapeutic strategies are under development. The current review focuses on the overall progress in the field of therapeutic approaches for the management/cure of HGPS. We have also discussed the new disease models that have been developed for the study of this rare disorder. Moreover, we have highlighted the therapeutic application of extracellular vesicles derived from stem cells against aging and aging-related disorders and, therefore, suggest the same for the treatment of HGPS.

Pilot Experience with ABO-Incompatible Kidney Transplantation as a Second Transplant

BACKGROUND

Despite advances in immunosuppressant medications, improvement in long-term survival for kidney transplant recipients has been more difficult to achieve. In fact, the number of patients with failing grafts who must either return to dialysis or undergo a second transplant is increasing. Second transplantation is associated with reduced mortality rates compared to remaining on dialysis after an initial graft loss. Nowadays, excellent ABO-incompatible kidney transplant outcomes have been achieved. However, there have been no reports on ABO-incompatible kidney transplantation as a second transplant.

PATIENTS AND METHODS

Three patients who received their graft from an ABO-incompatible living donor at our institution as a second transplant were enrolled in this study. We focused on immunosuppressive therapy for second ABO-incompatible kidney transplantation, donor-specific antibody status before the second transplant, patient and graft survivals, and complications.

RESULTS

All 3 patients successfully underwent ABO-incompatible kidney transplantation as a second transplant with a follow-up period of 141, 39, and 24 months. Patient and graft survival rates were 100%.

CONCLUSIONS

ABO-incompatible kidney transplantation may be an acceptable treatment for patients who need a second renal replacement therapy after their initial graft failure.

Downregulation of GATA6 in mTOR-inhibited human aortic endothelial cells: effects on TNF-α-induced VCAM-1 expression and monocytic cell adhesion

Increased expression of vascular cell adhesion molecule 1 (VCAM-1) on the aortic endothelium is an early marker of atherogenesis, promoted in part by elevated levels of inflammatory cytokines such as TNF-α. Mammalian target of rapamycin (mTOR) is a ubiquitous signaling molecule that has been considered to contribute to diverse cellular processes through mTOR complex 1 (mTORC1) or complex 2 (mTORC2). This study aimed to elucidate the role of mTOR signaling in TNF-α-induced VCAM-1 expression by the arterial endothelium. Primary human aortic endothelial cells (HAECs) were treated with low-dose (0.1 ng/ml) TNF-α, and VCAM-1 expression was measured by real-time quantitative PCR, Western blot analysis, and flow cytometry. Inhibition of mTOR through siRNA-mediated depletion or treatment with chemical inhibitors rapamycin or torin 1 suppressed VCAM1 transcription, which translated to inhibition of VCAM-1 surface expression by HAECs and concomitant decreased adhesion of monocytes. A promoter luciferase assay and chromatin immunoprecipitation indicated that mTOR regulated VCAM1 transcription through a mechanism involving transcription factor GATA6. Activation of PKC-α and an increase in miR-200a-3p expression, caused by mTOR inhibition but not disruption of mTORC1 or mTORC2 singly or together, decreased TNF-α-induced GATA6 expression and its enrichment at the VCAM1 promoter. In conclusion, mTOR inhibition activates PKC-α independently of disruption of mTORC1 and/or mTORC2, which challenges the conventional wisdom regarding mTOR signaling. Moreover, mTOR signals through transcriptional and posttranscriptional mechanisms to elicit maximal cytokine-induced endothelial inflammation that precedes atherosclerosis. NEW & NOTEWORTHY Both mammalian target of rapamycin (mTOR) complex 1 (mTORC1) and mTORC2 contribute to PKC-α activation in the human aortic endothelium. Inhibition of mTOR is not equivalent to disruption of mTORC1 and/or mTORC2 in affecting human aortic endothelial cell signaling. Specifically, inhibition of mTOR causes PKC-α activation and miR-200a-3p upregulation, which independently suppresses TNF-α-induced transcription factor GATA6 expression and subsequently inhibits VCAM-1 expression and monocytic cell adhesion onto the aortic endothelium.

Effect of sirolimus on carotid atherosclerosis in kidney transplant recipients: data derived from a prospective randomized controlled trial

Background

In animal models, the mammalian target of rapamycin inhibitors (mTORIs) may prevent atherogenesis by the regulation of homeostasis of cholesterol and by a reduced inflammatory response. The aim of this study is to compare the carotid intima–media thickness (cIMT) between de novo tacrolimus/mycophenolate and tacrolimus/sirolimus at low doses. The cIMT is considered a surrogate marker of atherosclerosis.

Methods

We evaluated cIMT at baseline and at 6 and 12 months after kidney transplantation in a database derived from a previously published trial. That trial had prospectively randomly assigned kidney transplant recipients older than 60 years of age to one of two groups: tacrolimus/sirolimus (n = 21) or tacrolimus/mycophenolate (n = 23). The cIMT was evaluated by using ultrasound in the common carotid artery wall on both sides.

Results

The total and high-density lipoprotein cholesterol levels were higher in the sirolimus group at 6 and 12 months. The cIMT decreased over time at 6 and 12 months in the sirolimus group (P = 0.012); this decrease continued to be significant in a model adjusted for age, sex, presence of diabetes, statin use and smoking.

Conclusions

The use of sirolimus plus tacrolimus de novo in kidney transplantation is associated with a reduction in cIMT after 12 months, a decrease more significant than seen with the combination of mycophenolate plus tacrolimus. This suggests a class effect of mTORI in the prevention of atherosclerosis.

Early intrathecal infusion of everolimus restores cognitive function and mood in a murine model of Alzheimer's disease

The discovery that mammalian target of rapamycin (mTOR) inhibition increases lifespan in mice and restores/delays many aging phenotypes has led to the identification of a novel potential therapeutic target for the treatment of Alzheimer's disease (AD). Among mTOR inhibitors, everolimus, which has been developed to improve the pharmacokinetic characteristics of rapamycin, has been extensively profiled in preclinical and clinical studies as anticancer and immunosuppressive agent, but no information is available about its potential effects on neurodegenerative disorders. Using a reliable mouse model of AD (3 × Tg-AD mice), we explored whether short-term treatment with everolimus injected directly into the brain by osmotic pumps was able to modify AD-like pathology with low impact on peripheral organs. We first established in non-transgenic mice the stability of everolimus at 37 °C in comparison with rapamycin and, then, evaluated its pharmacokinetics and pharmacodynamics profiles through either a single peripheral (i.p.) or central (i.c.v.) route of administration. Finally, 6-month-old (symptomatic phase) 3 × Tg-AD mice were treated with continuous infusion of either vehicle or everolimus (0.167 μg/μl/day, i.c.v.) using the osmotic pumps. Four weeks after the beginning of infusion, we tested our hypothesis following an integrated approach, including behavioral (tests for cognitive and depressive-like alterations), biochemical and immunohistochemical analyses. Everolimus (i) showed higher stability than rapamycin at 37 °C, (ii) poorly crossed the blood-brain barrier after i.p. injection, (iii) was slowly metabolized in the brain due to a longer t_1/2 in the brain compared to blood, and (iv) was more effective in the CNS when administered centrally compared to a peripheral route. Moreover, the everolimus-induced mTOR inhibition reduced human APP/Aβ and human tau levels and improved cognitive function and depressive-like phenotype in the 3 × Tg-AD mice. The intrathecal infusion of everolimus may be effective to treat early stages of AD-pathology through a short and cyclic administration regimen, with short-term outcomes and a low impact on peripheral organs.

Introduction of everolimus in kidney transplant recipients at a late posttransplant stage

This minireview focuses on the current knowledge about the introduction of everolimus (EVL), a mammalian target of rapamycin inhibitor, with calcineurin inhibitor (CNI) elimination or minimization in kidney transplant recipients at a late posttransplant stage. Within, we have summarized two major clinical trials, ASCERTAIN and APOLLO, and seven other retrospective or nonrandomized studies. In the open-label multicenter ASCERTAIN study, the estimated glomerular filtration rate (eGFR) at 24 mo after conversion was not significantly different between three groups-EVL with CNI elimination, CNI minimization and continued CNI unchanged-at a mean of 5.4 years after transplantation. However, recipients with baseline creatinine clearance higher than 50 mL/min had a greater increase in measured GFR after CNI elimination. In the open-label multicenter APOLLO study, adjusted eGFR within the on-treatment population was significantly higher in the EVL continuation group than in the CNI continuation group at 12 mo after conversion at a mean of 7 years posttransplantation. Other studies on recipients without adverse events and already having satisfactory renal function showed favorable graft function by EVL late-induction with CNI elimination or reduction. These studies showed that chronic allograft nephropathy, CNI nephrotoxicity, CNI arteriolopathy, cancer and viral infection (especially cytomegalovirus infection) may be good indications for late conversion to EVL.

Platelet membrane-coated nanoparticle-mediated targeting delivery of Rapamycin blocks atherosclerotic plaque development and stabilizes plaque in apolipoprotein E-deficient (ApoE-/-) mice

Although certain success has been achieved in atherosclerosis treatment, tremendous challenges remain in developing more efficient strategies to treat atherosclerosis. Platelets have inherent affinity to plaques and naturally home to atherosclerotic sites. Rapamycin features potent anti-atherosclerosis effect, but its clinical utility is limited by its low concentration at the atherosclerotic site and severe systemic toxicity. In the present study, we used platelet membrane-coated nanoparticles (PNP) as a targeted drug delivery platform to treat atherosclerosis through mimicking platelets' inherent targeting to plaques. PNP displayed 4.98-fold greater radiant efficiency than control nanoparticles in atherosclerotic arterial trees, indicating its effective homing to atherosclerotic plaques in vivo. In an atherosclerosis model established in apolipoprotein E-deficient mice, PNP encapsulating rapamycin significantly attenuated the progression of atherosclerosis and stabilized atherosclerotic plaques. These results demonstrated the perfect efficacy and pro-resolving potential of PNP as a targeted drug delivery platform for atherosclerosis treatment.

Everolimus as cancer therapy: Cardiotoxic or an unexpected antiatherogenic agent? A narrative review

Everolimus (EVE) is now approved by many agencies for the treatment of variable neoplasms. The risk for adverse events with this agent is not adequately defined. The purpose of this review is to summarize the EVE-induced cardiotoxic effect as an antineoplastic factor on patients who received the specific drug and to evaluate any possible antiatherogenic effects due to systemic use of the drug. Articles were searched on PubMed until August 2017. Articles included an expanded-access clinical trial, as well as phase 2 or 3 clinical trials (most of them were randomized). Three experimental studies that provided evidence for the possible antiatherogenic action of EVE were also included. In addition, only studies that evaluated the systemic use of the drug were included. To be eligible for inclusion, trials should have evaluated patients with malignancy, treated by EVE, or assessed the antiatherogenic effect of the systemic use of EVE through clinical or experimental studies. Only articles written in English language were included. No direct cardiotoxic adverse effects (arrhythmia, acute coronary event, heart failure, and echocardiography pathologic findings) were reported. Patients appeared to have a risk of developing adverse events that could be associated with the risk factors of cardiovascular disease. In all clinical studies, patients suffered hyperglycemia, and in most of them, hyperlipidemia was observed. Fewer studies have reported the incidence of hypertension. Finally, there is evidence claiming that EVE has an antiatherogenic action. Three experimental studies have shown that the systemic use of EVE in mice or rabbits with atherosclerotic lesions led to the reduction in atheromatous plaque growth. However, we could not find any clinical study that showed similar results in patients with cancer. To sum up, the only reported cardiac adverse event of EVE treatment in patients with cancer is indirect. They are associated with the risk factors of cardiovascular disease (hyperglycemia, hyperlipidemia, and hypertension), which are mainly mild and easily manageable. Further research and data that support the antiatherogenic action of EVE are needed.

mTOR drives cerebral blood flow and memory deficits in LDLR-/- mice modeling atherosclerosis and vascular cognitive impairment

We recently showed that mTOR attenuation blocks progression and abrogates established cognitive deficits in Alzheimer's disease (AD) mouse models. These outcomes were associated with the restoration of cerebral blood flow (CBF) and brain vascular density (BVD) resulting from relief of mTOR inhibition of NO release. Recent reports suggested a role of mTOR in atherosclerosis. Because mTOR drives aging and vascular dysfunction is a universal feature of aging, we hypothesized that mTOR may contribute to brain vascular and cognitive dysfunction associated with atherosclerosis. We measured CBF, BVD, cognitive function, markers of inflammation, and parameters of cardiovascular disease in LDLR-/- mice fed maintenance or high-fat diet ± rapamycin. Cardiovascular pathologies were proportional to severity of brain vascular dysfunction. Aortic atheromas were reduced, CBF and BVD were restored, and cognitive dysfunction was attenuated potentially through reduction in systemic and brain inflammation following chronic mTOR attenuation. Our studies suggest that mTOR regulates vascular integrity and function and that mTOR attenuation may restore neurovascular function and cardiovascular health. Together with our previous studies in AD models, our data suggest mTOR-driven vascular damage may be a mechanism shared by age-associated neurological diseases. Therefore, mTOR attenuation may have promise for treatment of cognitive impairment in atherosclerosis.

Impact of immunosuppressive therapy on arterial stiffness in kidney transplantation: are all treatments the same?

Arterial stiffness is a biologic process related to ageing and its relationship with cardiovascular risk is well established. Several methods are currently available for non-invasive measurement of arterial stiffness that provide valuable information to further assess patients’ vascular status in real time. In kidney transplantation recipients, several factors could accelerate the stiffness process, such as the use of calcineurin inhibitors (CNIs), the presence of chronic kidney disease and other classical cardiovascular factors, which would explain, at least in part, the high cardiovascular mortality and morbidity. Despite the importance of arterial stiffness as a biomarker of cardiovascular risk, and unlike other cardiovascular risk factors (e.g. left ventricular hypertrophy), only a few clinical trials or retrospective studies of kidney recipients have evaluated its impact. In this review we describe the clinical impact of arterial stiffness as a prognostic marker of cardiovascular disease and the effects of different immunosuppressive regimens on its progression, focusing on the potential benefits of CNI-sparing protocols and supporting the rationale for individualization of immunosuppression in patients with lower arterial elasticity. Among the immunosuppressive drugs, a belatacept-based regimen seems to offer better vascular protection compared with CNIs, although further studies are needed to confirm the preliminary positive results.

A conserved KLF-autophagy pathway modulates nematode lifespan and mammalian age-associated vascular dysfunction

Loss of protein and organelle quality control secondary to reduced autophagy is a hallmark of aging. However, the physiologic and molecular regulation of autophagy in long-lived organisms remains incompletely understood. Here we show that the Kruppel-like family of transcription factors are important regulators of autophagy and healthspan in C. elegans, and also modulate mammalian vascular age-associated phenotypes. Kruppel-like family of transcription factor deficiency attenuates autophagy and lifespan extension across mechanistically distinct longevity nematode models. Conversely, Kruppel-like family of transcription factor overexpression extends nematode lifespan in an autophagy-dependent manner. Furthermore, we show the mammalian vascular factor Kruppel-like family of transcription factor 4 has a conserved role in augmenting autophagy and improving vessel function in aged mice. Kruppel-like family of transcription factor 4 expression also decreases with age in human vascular endothelium. Thus, Kruppel-like family of transcription factors constitute a transcriptional regulatory point for the modulation of autophagy and longevity in C. elegans with conserved effects in the murine vasculature and potential implications for mammalian vascular aging.KLF family transcription factors (KLFs) regulate many cellular processes, including proliferation, survival and stress responses. Here, the authors position KLFs as important regulators of autophagy and lifespan in C. elegans, a role that may extend to the modulation of age-associated vascular phenotypes in mammals.

mTOR signaling promotes foam cell formation and inhibits foam cell egress through suppressing the SIRT1 signaling pathway

Atherosclerosis (AS) is a chronic immuno‑inflammatory disease accompanied by dyslipidemia. The authors previously demonstrated that sirtuin 1 (SIRT1) may prevent atherogenesis through influencing the liver X receptor/C‑C chemokine receptor type 7/nuclear factor‑κB (LXR‑CCR7/NF‑κB) signaling pathway. Previous studies have suggested a role for mammalian target of rapamycin (mTOR) signaling in the pathogenesis of cardiovascular diseases. The present study investigated the potential association between mTOR signaling and SIRT1‑LXR‑CCR7/NF‑κB signaling (SIRT1 signaling) in AS pathogenesis. To induce foam cell formation, U937 cells were differentiated into macrophages by exposure to phorbol 12‑myristate 13‑acetate (PMA) for 24 h, followed by treatment with palmitate and oxidized low density lipoprotein for a further 24 h. Oil red O staining revealed a large accumulation of lipid droplets present in foam cells. Western blot analysis demonstrated increased protein levels of phosphorylated (p)‑mTOR and its downstream factor p‑ribosomal protein S6 kinase (p70S6K). Reverse transcription‑quantitative polymerase chain reaction and western blot analyses additionally revealed decreased expression of SIRT1, LXRα and CCR7 and increased expression of NF‑κB and its downstream factor tumor necrosis factor‑α (TNF‑α) in an atherogenetic condition induced by lysophosphatidic acid (LPA). In addition, abundant lipid droplets accumulated in U937‑LPA‑treated foam cells. Rapamycin, an mTOR inhibitor, suppressed the expression and activity of mTOR and p70S6K, however enhanced expression of SIRT1, LXRα, and CCR7. Conversely, rapamycin deceased TNF‑α and NF‑κB activity, the latter of which was further confirmed by immunofluorescence analysis demonstrating increased levels of NF‑κB present in the cytoplasm compared with the nucleus. The findings of the present study suggest that mTOR signaling promotes foam cell formation and inhibits foam cell egress via suppression of SIRT1 signaling.

Sirolimus Associated with Tacrolimus at Low Doses in Elderly Kidney Transplant Patients: A Prospective Randomized Controlled Trial

OBJECTIVES

There is no consensus on the best immunosuppressive regimen for elderly renal transplant recipients. The objective of this study was to assess cytomegalovirus infection incidence and kidney transplant outcomes in elderly recipients treated with mammalian target of rapamycin inhibitors sirolimus/ tacrolimus at low doses compared with those receiving tacrolimus/mycophenolate sodium.

MATERIALS AND METHODS

In this single-center prospective randomized study (Trial Registration No. NCT02683291), kidney transplant recipients over 60 years of age were randomly allocated into 2 groups: tacrolimus-sirolimus (21 patients) and tacrolimus-mycophenolate (23 patients). Cytomegalovirus infection rate and patient survival, biopsy-proven acute rejection, and renal function at 12 months were assessed.

RESULTS

Cytomegalovirus infection rate was higher in the mycophenolate group (60.9%) than in the sirolimus group (16.7%; P = .004). The rates of biopsy-proven acute rejection, patient survival, graft survival, and estimated glomerular filtration rate over 12 months did not significantly differ between groups.

CONCLUSIONS

The incidence of cytomegalovirus infection was significantly lower in the sirolimus group. The use of tacrolimus combined with sirolimus in elderly kidney transplant recipients is safe.

Antianginal Therapy for Stable Ischemic Heart Disease

Chronic angina pectoris is associated with considerable morbidity and mortality, especially if treated suboptimally. For many patients, aggressive pharmacologic intervention is necessary in order to alleviate anginal symptoms. The optimal treatment of stable ischemic heart disease (SIHD) should be the prevention of angina and ischemia, with the goal of maximizing both quality and quantity of life. In addition to effective risk factor modification with lifestyle changes, intensive pharmacologic secondary prevention is the therapeutic cornerstone in managing patients with SIHD. Current guidelines recommend a multifaceted therapeutic approach with β-blockers as first-line treatment. Another important pharmacologic intervention for managing SIHD is nitrates. Nitrates can provide both relief of acute angina and can be used prophylactically before exposure to known triggers of myocardial ischemia to prevent angina. Additional therapeutic options include calcium channel blockers and ranolazine, an inhibitor of the late inward sodium current, that can be used alone or in addition to nitrates or β-blockers when these agents fail to alleviate symptoms. Ranolazine appears to be particularly effective for patients with microvascular angina and endothelial dysfunction. In addition, certain antianginal therapies are approved in Europe and have been shown to improve symptoms, including ivabradine, nicorandil, and trimetazidine; however, these have yet to be approved in the United States. Ultimately, there are several different medications available to the physician for managing the patient with SIHD having chronic angina, when either used alone or in combination. The purpose of this review is to highlight the most important therapeutic approaches to optimizing contemporary treatment in response to individual patient needs.

Modulation of Immunologic Response by Preventive Everolimus Application in a Rat CPB Model

Everolimus (EVL) is widely used in solid organ transplantation. It is known to have antiproliferative and immunosuppressive abilities via inhibition of the mTOR pathway. Preventive EVL administration may lower inflammation induced by cardiopulmonary bypass (CPB) and reduce systemic inflammatory response syndrome (SIRS). After oral loading with EVL 2.5 mg/kg/day (n = 11) or placebo (n = 11) for seven consecutive days, male Wistar rats (400-500 g) were connected to a miniaturised heart-lung-machine performing a deep hypothermic circulatory arrest protocol. White blood cells (WBC) were significantly reduced in EVL-pretreated animals before start of CPB with a preserved reduction by trend at all other time points. Ischemia/reperfusion led to decreased glucose levels. Application of EVL significantly increased glucose levels after reperfusion. In addition, potassium levels were significantly lower in EVL-treated animals at the end of reperfusion. Immunoblotting revealed increased S6 levels after CPB. EVL decreased phosphorylation of S6 in the heart and kidney, which indicates an inhibition of mTOR pathway. Moreover, EVL significantly modified phosphorylation of AKT, while decreasing IL2, IL6, RANTES, and TNFα (n = 6). Preventive application of EVL may modulate inflammation by inhibition of mammalian target of rapamycin (mTOR) pathway and reduction of proinflammatory cytokines. This may be beneficial to evade SIRS-related morbidities after CPB.

Vitexin alleviates ox-LDL-mediated endothelial injury by inducing autophagy via AMPK signaling activation

Endothelial cell injury plays a crucial role in the development and pathogenesis of cardiovascular disease. Vitexin is a natural flavonoid characterized by anti-oxidative and anti-inflammatory properties. The purpose of this study was to investigate the effects of vitexin on ox-LDL-induced endothelial dysfunction and to explore the underlying molecular mechanisms. In the present study, vitexin was found to play a protective role against ox-LDL-induced endothelial injury. Vitexin significantly promoted cell viability and inhibited apoptosis in ox-LDL-treated HUVECs. The up-regulation of cleaved Caspase-3, cleaved Caspase-9 and Bax induced by ox-LDL were inhibited by treatment with vitexin; meanwhile, the down-regulation of Bcl-2 was suppressed by vitexin. Pretreatment with vitexin was found to inhibit the ox-LDL-induced overexpression of IL-1β, IL-6, TNF-α, E-selectin, ICAM1 and VCAM1. Moreover, vitexin reduced ox-LDL-induced oxidative stress by inhibiting the production of ROS and MDA, and by promoting the expression of SOD. Furthermore, we had shown that vitexin protected against the ox-LDL induced cell injury by activating autophagy. The protective effects of vitexin in ox-LDL-treated HUVECs were all reversed following treatment with the autophagy inhibitor 3-MA. In addition, we found that vitexin increased the expression of p-AMPK and decreased the expression of p-mTOR. The combination of the AMPK inhibitor Compound C plus vitexin significantly reversed the effects of vitexin in ox-LDL-treated HUVECs, such as the inhibition of autophagy, reduction in cell viability, increase in apoptosis and ROS production. In conclusion, these data suggest that vitexin ameliorates ox-LDL-mediated endothelial injury by inducing autophagy via AMPK signaling.

Clinical Experience of Late Conversion From Antimetabolites With Standard Exposure Calcineurin Inhibitors to Everolimus With Calcineurin Inhibitor Minimization in Stable Kidney Transplant Recipients With Good Renal Function

INTRODUCTION

This study describes our clinical experience of late conversion from antimetabolites with standard exposure calcineurin inhibitors (CNIs) to everolimus with CNI minimization in stable kidney transplant recipients with good graft function.

PATIENTS AND METHODS

A 1-year retrospective pilot study of 26 kidney recipients converted from antimetabolites with standard exposure CNIs to everolimus with CNI minimization was performed. The recipients enrolled in this study had normal or slightly impaired renal function defined as a serum creatinine value <2.0 mg/dL, and normal or slightly increased albuminuria defined as a urinary albumin excretion rate <100 mg/g creatinine.

RESULTS

The median time from transplant to conversion was 39.5 months posttransplant (range, 3-275). Treatment with everolimus was stopped owing to adverse events in 11 patients (42.3%). In the analysis of the patients in whom everolimus was maintained, the mean estimated glomerular filtration rate (eGFR) significantly increased from 50.7 ± 11.9 mL/min/1.73 m(2) at baseline to 53.6 ± 13.9 mL/min/1.73 m(2) at 1 year after conversion. In the patients in whom everolimus was stopped during the observation period, there was no difference in eGFR between baseline and 1 year after conversion.

CONCLUSIONS

This study demonstrated that, among the patients converted to everolimus at a late stage, there was no deterioration in renal function whether everolimus was maintained or stopped within 1 year after conversion.

Severe Atherosclerosis and Hypercholesterolemia in Mice Lacking Both the Melanocortin Type 4 Receptor and Low Density Lipoprotein Receptor

Dysfunction of the melanocortin system can result in severe obesity accompanied with dyslipidemia and symptoms of the metabolic syndrome but the effect on vascular atherogenesis is not known. To study the impact of obesity and dyslipidemia on the cardiovascular system, we generated mice double-deficient for the melanocortin type 4 receptor (Mc4rmut mice) and the LDL receptor (Ldlr-/- mice). Mc4rmut mice develop obesity due to hyperphagia. Double-mutant mice (Mc4rmut;Ldlr-/-) exhibited massive increases in body weight, plasma cholesterol and triacylglycerol levels and developed atherosclerosis. Atherosclerotic lesion size was affected throughout the aortic root and brachiocephalic artery not only under semisynthetic, cholesterol-containing diet but also under cholesterol-free standard chow. The Mc4rmut mice developed a hepatic steatosis which contributes to increased plasma cholesterol levels even under cholesterol-free standard chow. Transcripts of cholesterol biosynthesis components and liver cholesterol levels did not significantly differ between wild-type and all mutant mouse strains but RNA sequencing data and biochemical measurements point to an altered bile acid elimination in Mc4rmut;Ldlr-/-. Therefore, the unchanged endogenous cholesterol biosynthesis together with a reduced hepatic VLDL and LDL-cholesterol clearance most likely led to increased plasma lipid levels and consequently to atherosclerosis in this animal model. Our data indicate that dysfunction of the melanocortin-regulated food intake and the resulting obesity significantly add to the proatherogenic lipoprotein profile caused by LDL receptor deficiency and, therefore, can be regarded as relevant risk factor for atherosclerosis.

Macrophage Apoptosis and Necrotic Core Development in Atherosclerosis: A Rapidly Advancing Field with Clinical Relevance to Imaging and Therapy

Cardiovascular diseases represent 1 of the main causes of death worldwide, and atherosclerosis is 1 of the major contributors leading to ischemic heart disease. Macrophages actively participate in all stages of atherosclerosis development, from plaque initiation to the transition to vulnerable plaques. Macrophage apoptosis, in particular, has been recognized as a critical step in the formation of the necrotic core, a key characteristic of unstable lesions. In this review, we discuss the role of macrophage apoptosis and clearance of apoptotic cells by efferocytosis in the development of atherosclerosis, with particular emphasis on their contribution to the development of the necrotic core and the clinical implications of this process for plaque stabilization. We consider the molecular triggers of macrophage apoptosis during atherogenesis, the role of endoplasmic reticulum (ER) stress, the roles of key cellular mediators of apoptosis and efferocytosis, and mechanisms of defective efferocytosis in the progression of atherosclerotic plaques. Finally, we discuss the important clinical implications of rapidly evolving macrophage science, such as novel approaches to imaging vulnerable atherosclerotic plaques with macrophage-sensitive positron emission tomography and magnetic resonance imaging, the role of macrophages in mediating beneficial pleiotropic actions of lipid-lowering therapies, and novel therapeutic modalities targeting ER stress, autophagy, and deficient efferocytosis. Advances in understanding the critical role of macrophages in the progression and destabilization of atherosclerosis have the potential to greatly improve the prevention and management of atherosclerotic diseases over the next decade.

Continuous administration of the mTORC1 inhibitor everolimus induces tolerance and decreases autophagy in mice

BACKGROUND AND PURPOSE

Everolimus is an allosteric inhibitor of the mechanistic target of rapamycin complex 1 (mTORC1) widely known for its potent autophagy stimulating properties. Because everolimus shows poor solubility and stability in aqueous solutions, long-term in vivo administration in preclinical models is challenging. The aim of the present study was to evaluate the effects of short-term and long-term everolimus administration on mTORC1 inhibition and autophagy induction in mice.

EXPERIMENTAL APPROACH

We developed a vehicle in which everolimus was solubilized and stable at 37°C for at least 1 month. Using osmotic minipumps, GFP microtubule-associated protein light chain 3 transgenic mice were treated continuously either with vehicle or everolimus (1.5 mg·kg^-1 per day) for 3 or 28 days. Alternatively, a regimen consisting of intermittent everolimus administration (every other day) for 56 days by oral gavage was used. Autophagy markers and mTORC1 activation status were investigated in the liver.

KEY RESULTS

As expected, everolimus inhibited mTORC1 and stimulated autophagy in the liver after 3 days of treatment. However, continuous administration for 28 days resulted in hyperactivation of the Akt1-mTORC1 pathway accompanied by a remarkable decrease in autophagy markers. Everolimus given intermittently for 56 days partially rescued mTORC1 sensitivity to the drug but without inducing autophagy. The failure to induce autophagy following long-term everolimus administration was due to uncoupling of the mTORC1 substrate unc-51 like autophagy activating kinase 1.

CONCLUSIONS AND IMPLICATIONS

Our data encourage the use of intermittent everolimus regimens to prevent tolerance and to extend its activity.

Oral sirolimus: A possible treatment for refractory angina pectoris in the elderly

Refractory angina pectoris (RAP) is a clinical problem, frequently encountered in the elderly, associated with high health-care costs. Until recently, the goal of RAP treatment aimed at improving the quality of life (QoL) because it was thought that mortality rates were not different between stable angina pectoris and RAP. Our purpose was at determining whether any mortality rate difference exists and whether any novel therapeutical solution might be translated into clinical practice. We therefore performed a literature review to assess current optimal treatment of RAP patients, including all studies involving the use of oral sirolimus and stents, although no consistent evidence was found for any specific treatment to improve survival, apart from minor QoL amelioration. A large mortality difference was seen between RAP and stable angina pectoris. On the other hand, therapeutic approaches to RAP patients showed frequent complications and several contraindications, depending on the procedure. We propose to inhibit instead of stimulating angiogenesis, by giving oral sirolimus, an immunosuppressive drug, thereby decreasing the atherosclerotic process and its evolution. Sirolimus was shown to decrease left ventricular mass (thus indirectly decreasing myocardial oxygen needs and consumption). It might stop and, in some cases, even enable regression of plaque progression. Sirolimus side effects are mild to moderate and wash-out rapidly at treatment discontinuation. Compared with current therapies sirolimus treatment is more health-care cost efficient. It should be important to design a trial in RAP patients powered to reduce mortality and QoL increase.

Everolimus treatment among patients with tuberous sclerosis affects serum lipid profile

BACKGROUND

The purpose of the study was to evaluate lipid homeostasis before and after treatment of everolimus, the mammalian target of the rapamycin (mTOR) inhibitor, among patients with tuberous sclerosis complex (TSC).

METHODS

The study group consisted of 15 patients with a diagnosis of subependymal giant cell astrocytoma (SEGA) related to TSC. The following lipid parameters were determined: total serum cholesterol (TCh), low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL), total serum triglyceride (TG) concentration at baseline, then after three and 12 months of observation. The values were compared with those of age-matched healthy controls.

RESULTS

In the study group TCh, LDL and HDL levels at baseline were significantly higher than in the control group. TCh and LDL levels were positively correlated with baseline SDS-BMI in TSC patients. Everolimus treatment resulted in significant increases of TCh (from 192.04±40.51mg/dl to 210.74±51.12mg/dl and to 216.69±45.43mg/dl; p=0.0273) and LDL (from 113.21±38.72mg/dl to 133.88±50.71mg/dl and to 141.58±40.67mg/dl; p=0.0006) after three and 12 months respectively. The differences between the TCh and LDL levels at baseline and after 12 months of therapy were negatively correlated with baseline SDS-BMI. The observed increase of BMI after 12 months was correlated with increases in TCh and LDL levels.

CONCLUSIONS

Patients with TSC have disrupted lipid homeostasis before and during treatment with everolimus, which might be partially connected to the mTOR-dependent nutritional status of the patients. There is a need to develop strategies for children with TSC treated with everolimus, who experience hyperlipidemia.

Multiple pathway assessment to predict anti-atherogenic efficacy of drugs targeting macrophages in atherosclerotic plaques

BACKGROUND

Macrophages play a central role in atherosclerosis development and progression, hence, targeting macrophage activity is considered an attractive therapeutic. Recently, we documented nanomedicinal delivery of the anti-inflammatory compound prednisolone to atherosclerotic plaque macrophages in patients, which did however not translate into therapeutic efficacy. This unanticipated finding calls for in-depth screening of drugs intended for targeting plaque macrophages.

METHODS AND RESULTS

We evaluated the effect of several candidate drugs on macrophage activity, rating overall performance with respect to changes in cytokine release, oxidative stress, lipid handling, endoplasmic reticulum (ER) stress, and proliferation of macrophages. Using this in vitro approach, we observed that the anti-inflammatory effect of prednisolone was counterbalanced by multiple adverse effects on other key pathways. Conversely, pterostilbene, T0901317 and simvastatin had an overall anti-atherogenic effect on multiple pathways, suggesting their potential for liposomal delivery.

CONCLUSION

This dedicated assay setup provides a framework for high-throughput assessment. Further in vivo studies are warranted to determine the predictive value of this macrophage-based screening approach and its potential value in nanomedicinal drug development for cardiovascular patients.