Beta Blockers Suppress Dextrose-Induced Endoplasmic Reticulum Stress, Oxidative Stress, and Apoptosis in Human Coronary Artery Endothelial Cells

Inhibition of protein glycation by vasodilatory β-blockers - In vitro studies and in silico analyses

Glycation is defined as a non-enzymatic reaction wherein reducing sugars interact with amino acid residues present in proteins, resulting in the formation of advanced glycation end-products (AGE). This biochemical phenomenon is linked to several pathological conditions, particularly cardiovascular disease (CVD) and diabetes, as it significantly contributes to the onset of endothelial dysfunction and inflammation. Given these connections, vasodilatory β-blockers (VBB) have garnered interest due to their multifaceted pharmacological effects that extend beyond traditional β-adrenergic blockade. These agents not only enhance endothelial function but also exhibit notable antioxidant and anti-inflammatory properties, which may be associated with their capacity to inhibit glycation processes. In our study, we examined these properties through an in vitro and in silico study utilizing bovine serum albumin (BSA) as a model with multiple carbohydrates and aldehydes as glycation agents. Furthermore, we evaluated the binding affinity of VBB to BSA and pro-inflammatory proteins via molecular docking. The results indicated that while VBB were effective in diminishing the rates of protein glycation their effectiveness was generally lower than that of aminoguanidine, a recognized anti-glycation agent. In contrast, molecular docking analyses suggested that the anti-inflammatory properties of VBB may be due to their competition with glycation agents for binding sites on BSA, as well as their interactions with proteins integral to the activation of pro-inflammatory signaling pathways.

Treatment of endothelial cell dysfunction in atherosclerosis: a new perspective integrating traditional and modern approaches

Atherosclerosis (AS), a prime causative factor in cardiovascular disease, originates from endothelial cell dysfunction (ECD). Comprising a vital part of the vascular endothelium, endothelial cells play a crucial role in maintaining vascular homeostasis, optimizing redox balance, and regulating inflammatory responses. More evidence shows that ECD not only serves as an early harbinger of AS but also exhibits a strong association with disease progression. In recent years, the treatment strategies for ECD have been continuously evolving, encompassing interventions ranging from lifestyle modifications to traditional pharmacotherapy aimed at reducing risk factors, which also have demonstrated the ability to improve endothelial cell function. Additionally, novel strategies such as promising biotherapy and gene therapy have drawn attention. These methods have demonstrated enormous potential and promising prospects in improving endothelial function and reversing AS. However, it is essential to remain cognizant that the current treatments still present significant challenges regarding therapeutic efficacy, long-term safety, and ethical issues. This article aims to provide a systematic review of these treatment methods, analyze the mechanisms and efficacy of various therapeutic strategies, with the goal of offering insights and guidance for clinical practice, and further advancing the prevention and treatment of cardiovascular diseases.

Cardiomodulatory Effects of Cardiometabolic and Antihyperglycemic Medications: The Roles of Oxidative and Endoplasmic Reticulum Stress

Uncontrolled hyperglycemia in people with diabetes is an established risk of premature cardiovascular disease. Repeated hypoglycemic events are also associated with increased cardiovascular mortality. Both hyperglycemia and hypoglycemia induce cellular stress, notably endoplasmic reticulum (ER) stress, a known promoter of cardiovascular disease. Contemporary anti-hyperglycemic drugs such as glucagon-like peptide 1 (GLP-1) receptor agonists and sodium-glucose cotransporter 2 (SGLT-2) inhibitors simultaneously inhibit oxidative stress and ER stress in human coronary artery endothelial cells. Similarly, other known cardioprotective drugs, such as statins and inhibitors of the renin-angiotensin-aldosterone system (RAAS) share a common pleiotropic effect of reducing cellular stress. Antioxidants reduce oxidative stress but may aggravate ER stress. This dichotomy of antioxidant effects may underline the unfavorable outcomes of clinical trials with antioxidant vitamin use. The aim of this review is to highlight the potential role of cellular stress reduction in cardioprotective effects of contemporary diabetes drugs. Future clinical trials are needed to test the hypothesis that cellular stress is the fundamental culprit in cardiovascular disease.

β-blockers and metabolic modulation: unraveling the complex interplay with glucose metabolism, inflammation and oxidative stress

The growing burden of metabolic disorders manifested by hypertension, type 2 diabetes mellitus, hyperlipidemia, obesity and non-alcoholic fatty liver disease presents a significant global health challenge by contributing to cardiovascular diseases and high mortality rates. Β-blockers are among the most widely used drugs in the treatment of hypertension and acute cardiovascular events. In addition to blocking the receptor sites for catecholamines, third-generation β-blockers with associated vasodilating properties, such as carvedilol and nebivolol, provide a broad spectrum of metabolic effects, including anti-inflammatory and antioxidant properties and a favorable impact on glucose and lipid metabolism. This review aims to report the impact of β-blockers on metabolic modulation based on available literature data. We present an overview of β-blockers and their pleiotropic properties, discuss mechanisms by which these drugs affect cellular metabolism and outline the future perspectives. The influence of β-blockers on glucose metabolism, insulin sensitivity, inflammation and oxidative stress is complex and varies depending on the specific β-blocker used, patient population and underlying health conditions. Recent evidence particularly highlights the potential role of vasodilatory and nitric oxide-mediated properties of nebivolol and carvedilol in improving glycemic control, insulin sensitivity, and lipid metabolism and mitigating oxidative stress and inflammation. It suggests that these drugs may be potential therapeutic options for patients with metabolic disorders, extending beyond their primary role in cardiovascular management.

Nebivolol protects the liver against lipopolysaccharide-induced oxidative stress, inflammation, and endoplasmic reticulum-related apoptosis through Chop and Bip/GRP78 signaling

This study aimed to examine the protective role of nebivolol (NEB) on liver tissue against the lipopolysaccharide (LPS)-induced sepsis model in rats by targeting endoplasmic reticulum (ER) stress-related binding immunoglobulin protein (Bip), CCAAT-enhancer-binding protein homologous protein (Chop) signaling pathways. Four groups, each comprising eight rats, were established: control, LPS, LPS + NEB, and NEB. Biochemical analyses included total oxidant status (TOS), serum aspartate transaminase (AST), and alanine aminotransferase (ALT) levels. Additionally, genetic assessments involved Chop and Bip/GRP78 mRNA expression levels, while histopathological examinations were conducted. Immunohistochemistry was used to determine interleukin-1 beta (IL-1 β) and caspase-3 levels. The LPS group exhibited significantly higher AST, ALT, oxidative stress index, and TOS levels compared to the control group. Moreover, the LPS group demonstrated markedly increased Chop and Bip/GRP78 mRNA expression compared to the control group. Immunohistochemical analysis of the LPS group revealed significant upregulation in IL-1β and caspase-3 expressions compared to the control group. Additionally, the LPS group showed significant hyperemia, mild hemorrhage, and inflammatory cell infiltrations. Comparatively, the LPS+NEB group exhibited a reversal of these alterations when compared to the LPS group. Collectively, our findings, suggest that NEB holds promise as a treatment in conditions where oxidative damage, inflammation, and ER stress-related apoptosis play significant roles in the pathogenesis.

Cardioprotective antihyperglycemic drugs ameliorate endoplasmic reticulum stress

Cellular stress, notably oxidative, inflammatory, and endoplasmic reticulum (ER) stress, is implicated in the pathogenesis of cardiovascular disease. Modifiable risk factors for cardiovascular disease such as diabetes, hypercholesterolemia, saturated fat consumption, hypertension, and cigarette smoking cause ER stress whereas currently known cardioprotective drugs with diverse pharmacodynamics share a common pleiotropic effect of reducing ER stress. Selective targeting of oxidative stress with known antioxidative vitamins has been ineffective in reducing cardiovascular risk. This "antioxidant paradox" is partially attributed to the unexpected aggravation of ER stress by the antioxidative agents used. In contrast, some of the contemporary antihyperglycemic drugs inhibit both oxidative stress and ER stress in human coronary artery endothelial cells. Unlike sulfonylureas, meglitinides, α glucosidase inhibitors, and thiazolidinediones, metformin, glucagon-like peptide 1 receptor agonists, and sodium-glucose cotransporter 2 inhibitors are the only antihyperglycemic drugs that reduce ER stress caused by pharmacological agents (tunicamycin) or hyperglycemic conditions. Clinical trials with selective ER stress modifiers are needed to test the suitability of ER stress as a therapeutic target for cardiovascular disease.

Endothelial cell dysfunction: Implications for the pathogenesis of peripheral artery disease

Peripheral artery disease (PAD) is caused by occluded or narrowed arteries that reduce blood flow to the lower limbs. The treatment focuses on lifestyle changes, management of modifiable risk factors and vascular surgery. In this review we focus on how Endothelial Cell (EC) dysfunction contributes to PAD pathophysiology and describe the largely untapped potential of correcting endothelial dysfunction. Moreover, we describe current treatments and clinical trials which improve EC dysfunction and offer insights into where future research efforts could be made. Endothelial dysfunction could represent a target for PAD therapy.

Endoplasmic reticulum stress: A common pharmacologic target of cardioprotective drugs

Despite the advances made in cardiovascular disease prevention, there is still substantial residual risk of adverse cardiovascular events. Contemporary evidence suggests that additional reduction in cardiovascular disease risk can be achieved through amelioration of cellular stresses, notably inflammatory stress and endoplasmic reticulum (ER) stress. Only two clinical trials with anti-inflammatory agents have supported the role of inflammatory stress in cardiovascular risk. However, there are no clinical trials with selective ER stress modifiers to test the hypothesis that reducing ER stress can reduce cardiovascular disease. Nevertheless, the ER stress hypothesis is supported by recent pharmacologic studies revealing that currently available cardioprotective drugs share a common property of reducing ER stress. These drug classes include angiotensin converting enzyme inhibitors, angiotensin II receptor blockers, mineralocorticoid receptor blockers, β-adrenergic receptor blockers, statins, and select antiglycemic agents namely, metformin, glucagon like peptide 1 receptor agonists and sodium glucose cotransporter 2 inhibitors. Although these drugs ameliorate common risk factors for cardiovascular disease, such as hypertension, hypercholesterolemia and hyperglycemia, their cardioprotective effects may be partially independent of their principal effects on cardiovascular risk factors. Clinical trials with selective ER stress modifiers are needed to test the hypothesis that reducing ER stress can reduce cardiovascular disease.

Transcription factor EB protects against endoplasmic reticulum stress in human coronary artery endothelial cells

Oxidative stress and endoplasmic reticulum (ER) stress promote atherogenesis while transcription factor EB (TFEB) inhibits atherosclerosis. Since reducing oxidative stress with antioxidants have failed to reduce atherosclerosis possibly because of aggravation of ER stress, we studied the effect of TFEB on ER stress in human coronary artery endothelial cells. ER stress was measured using the secreted alkaline phosphatase assay. Expression and phosphorylation of key mediators of unfolded protein response (UPR). TFEB, inositol-requiring enzyme 1α (IRE1α), phospho-IRE1α, protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK), phospho-PERK, and activating transcription factor 6 (ATF6) expression were measured by Western blot. The effect of TFEB gain- and loss-of-function on ER stress were assessed with a plasmid expressing a constitutively active form of TFEB and via siRNA-mediated silencing, respectively. Treatment with tunicamycin (TM) and thapsigargin (TG) increased TFEB expression by 42.8% and 42.3%, respectively. In HCAEC transfected with the TFEB siRNA, treatment with either TM, TG or high-dextrose increased IRE1α and PERK phosphorylation and ATF6 levels significantly more compared to cells transfected with the control siRNA and treated similarly. Furthermore, transient transfection with a plasmid expressing a constitutively active form of TFEB reduced ER stress. Increased expression of TFEB inhibited ER stress in HCAEC treated with pharmacologic (TM and TG) and physiologic (high-dextrose) ER stress inducers, while TFEB knockout aggravated ER stress caused by these ER stress inducers. TFEB-mediated ER stress reduction may contribute to its anti-atherogenic effects in HCAEC and may be a novel target for drug development.

Sustainable Release of Propranolol Hydrochloride Laden with Biconjugated-Ufasomes Chitosan Hydrogel Attenuates Cisplatin-Induced Sciatic Nerve Damage in In Vitro/In Vivo Evaluation

Peripheral nerve injuries significantly impact patients' quality of life and poor functional recovery. Chitosan-ufasomes (CTS-UFAs) exhibit biomimetic features, making them a viable choice for developing novel transdermal delivery for neural repair. This study aimed to investigate the role of CTS-UFAs loaded with the propranolol HCl (PRO) as a model drug in enhancing sciatica in cisplatin-induced sciatic nerve damage in rats. Hence, PRO-UFAs were primed, embedding either span 20 or 60 together with oleic acid and cholesterol using a thin-film hydration process based on full factorial design (24). The influence of formulation factors on UFAs' physicochemical characteristics and the optimum formulation selection were investigated using Design-Expert® software. Based on the optimal UFA formulation, PRO-CTS-UFAs were constructed and characterized using transmission electron microscopy, stability studies, and ex vivo permeation. In vivo trials on rats with a sciatic nerve injury tested the efficacy of PRO-CTS-UFA and PRO-UFA transdermal hydrogels, PRO solution, compared to normal rats. Additionally, oxidative stress and specific apoptotic biomarkers were assessed, supported by a sciatic nerve histopathological study. PRO-UFAs and PRO-CTS-UFAs disclosed entrapment efficiency of 82.72 ± 2.33% and 85.32 ± 2.65%, a particle size of 317.22 ± 6.43 and 336.12 ± 4.9 nm, ζ potential of -62.06 ± 0.07 and 65.24 ± 0.10 mV, and accumulatively released 70.95 ± 8.14% and 64.03 ± 1.9% PRO within 6 h, respectively. Moreover, PRO-CTS-UFAs significantly restored sciatic nerve structure, inhibited the cisplatin-dependent increase in peripheral myelin 22 gene expression and MDA levels, and further re-established sciatic nerve GSH and CAT content. Furthermore, they elicited MBP re-expression, BCL-2 mild expression, and inhibited TNF-α expression. Briefly, our findings proposed that CTS-UFAs are promising to enhance PRO transdermal delivery to manage sciatic nerve damage.

Effect of anti-hyperglycemic drugs on endoplasmic reticulum (ER) stress in human coronary artery endothelial cells

Endoplasmic reticulum (ER) stress plays a critical role in progression of diabetes and development of complications, notably cardiovascular disease. Some of the contemporary anti-hyperglycemic drugs have been shown to inhibit ER stress. To extend these observations, the effects of various anti-hyperglycemic agents were screened for their effects on ER stress. Seven classes of anti-hyperglycemic drugs were screened including sulfonylureas, meglitinides, metformin, α glucosidase inhibitors, thiazolidinedione, glucagon like peptide 1 (GLP-1) receptor agonists and sodium-glucose cotransporter 2 (SGLT-2) inhibitors. ER stress was measured in human coronary artery endothelial cells (HCAEC) either treated with tunicamycin (TM) or cultured in hyperglycemic conditions (27.5 mM dextrose). The ER stress was measured with the secreted alkaline phosphatase (ES-TRAP) assay. Mediators of the unfolded protein response, including activating transcription factor 6 (ATF6), glucose-regulated protein 78 (GRP78), phospho-inositol-requiring enzyme 1α (pIRE1α), IRE1α, phospho-protein kinase R (PKR)-like endoplasmic reticulum kinase (pPERK), and PERK were measured by Western blot. Metformin, GLP-1 receptor agonists (GLP-1, exendin 4, liraglutide, albiglutide, and lixisenatide) and SGLT-2 inhibitors (canagliflozin, dapagliflozin, and empagliflozin) were the only anti-hyperglycemic drugs screened that reduced ER stress caused by pharmacological (tunicamycin) or hyperglycemic conditions. High-dextrose and TM increased IRE1α and PERK phosphorylation and ATF6 and GRP78 expression, while treatment with metformin, liraglutide (a GLP-1 receptor agonist) and dapagliflozin (a SGLT-2 inhibitor), suppressed IRE1α and PERK phosphorylation as well as ATF6 and GRP78 expression. Thus, the cardioprotective effects of metformin, some of the GLP-1 receptor agonists and SGLT2 inhibitors may be partly related to their ability to reduce ER stress.

Smyd3-PARP16 axis accelerates unfolded protein response and vascular aging

Vascular endothelial cell senescence and endoplasmic reticulum (ER) stress induced unfolded protein response (UPR) are two critical contributors to individual aging. However, whether these two biological events have crosstalk and are controlled by shared upstream regulators are largely unknown. Here, we found PARP16, a member of the Poly (ADP-ribose) polymerases family that tail-anchored ER transmembrane, was upregulated in angiotensin II (Ang II)-induced vascular aging and promoted UPR. Further, PARP16 was epigenetically upregulated by Smyd3, a histone H3 lysine 4 methyltransferase that bound to the promotor region of Parp16 gene and increased H3K4me3 level to activate its host gene’s transcription. Intervention of either Smyd3 or PARP16 ameliorated vascular aging associated phenotypes in both cell and mice models. This study identified Smyd3-PARP16 as a novel signal axis in regulating UPR and endothelial senescence, and targeting this axis has implications in preventing vascular aging and related diseases.

Syndecan-4 as a Marker of Endothelial Dysfunction in Patients with Resistant Hypertension

(1) Background: Arterial hypertension (HTN) is one of the most relevant cardiovascular risk factors. Nowadays multiple pharmaceutical treatment options exist with novel interventional methods (e.g., baroreflex activation therapy (BAT)) as a last resort to treat patients with resistant HTN. Although pathophysiology behind resistant HTN is still not fully understood. There is evidence that selected biomarkers may be involved in the pathophysiology of HTN. (2) Methods: We investigated serum SDC4-levels in patients suffering from resistant HTN before and 6 months after BAT implantation. We collected 19 blood samples from patients with resistant HTN and blood pressure above target and measured serum SDC4-levels. (3) Results: Our results showed high serum SDC4-levels in patients with resistant HTN as compared to a healthy population. Patients with both, resistant HTN and diabetes mellitus type II, demonstrated higher serum SDC4-levels. β-blockers had lowering effects on serum SDC4-levels, whereas calcium channel blockers were associated with higher levels of serum SDC4. BAT implantation did not lead to a significant difference in serum SDC4-levels after 6 months of therapy. (4) Conclusion: Based on our results we propose SDC4 is elevated in patients suffering from resistant HTN. Thus, SDC4 might be a potential marker for endothelial dysfunction in patients with resistant hypertension.

Metoprolol, N-Acetylcysteine, and Escitalopram Prevents Chronic Unpredictable Mild Stress-Induced Depression by Inhibition of Endoplasmic Reticulum Stress

Background: Endoplasmic reticulum stress (ERS) has been recently suggested to be activated in the major depressive disorder (MDD). However, whether ERS is a potential therapeutic target for MDD is largely unknown. Here we attempted to assess the preventive effect of metoprolol (MET), N-acetylcysteine (NAC), and escitalopram (ESC) on chronic unpredictable mild stress (CUMS)-induced depression and investigate whether ERS mediates the antidepressant role of these drugs. Method: Forty-five sprague-dawley rats were randomly divided into five groups: control, CUMS, CUMS+ESC, CUMS+NAC, and CUMS+MET. Weight measurement, open field activity and sucrose preference were performed before and after stress. Hippocampal nerve cells and capillary ultrastructure were observed by transmission electron microscope, and hippocampal cells apoptosis were detected by flow cytometry. Furthermore, expression of ERS markers glucose-regulated protein 78 (GRP78), C/EBP-homologous protein (CHOP), and caspase-12 were measured by western blot and qRT-PCR. Results: The CUMS-induced rats showed significantly increased depressive-like behaviors including decreased open field activity and sucrose preference. Moreover, CUMS-exposed rats exhibited significantly increased hippocampal cell apoptosis, and showed damage in hippocampal nerve cells and capillary ultrastructure. Furthermore, ESC and NAC not only mitigated depressive-like behaviors, but also decreased apoptosis and pathologies, while MET fail to decrease apoptosis. Moreover, CUMS stimulation significantly elevated ERS by increasing the levels of GRP78, CHOP, and decreasing the level of caspase-12, while ESC, NAC, and MET significantly decreased the ERS. Conclusion: ESC, NAC, and MET might prevent the MDD partly through inactivating the ERS. These findings demonstrated ERS as a novel treatment target for depression.

The biochemical alterations underlying post-burn hypermetabolism

A severe burn can trigger a hypermetabolic state which lasts for years following the injury, to the detriment of the patient. The drastic increase in metabolic demands during this phase renders it difficult to meet the body's nutritional requirements, thus increasing muscle, bone and adipose catabolism and predisposing the patient to a host of disorders such as multi-organ dysfunction and sepsis, or even death. Despite advances in burn care over the last 50 years, due to the multifactorial nature of the hypermetabolic phenomenon it is difficult if not impossible to precisely identify and pharmacologically modulate the biological mediators contributing to this substantial metabolic derangement. Here, we discuss biomarkers and molecules which play a role in the induction and mediation of the hypercatabolic condition post-thermal injury. Furthermore, this thorough review covers the development of the factors released after burns, how they induce cellular and metabolic dysfunction, and how these factors can be targeted for therapeutic interventions to restore a more physiological metabolic phenotype after severe thermal injuries. This article is part of a Special Issue entitled: Immune and Metabolic Alterations in Trauma and Sepsis edited by Dr. Raghavan Raju.

Dickkopf1 destabilizes atherosclerotic plaques and promotes plaque formation by inducing apoptosis of endothelial cells through activation of ER stress

Several clinical studies reported that Dickkopf1 (DKK1) plasma levels are correlated with atherosclerosis. However, the impact of DKK1 on the formation and vulnerability of atherosclerotic plaques remains elusive. This study investigated DKK1’s effects on enlargement and destabilization of plaques by targeting endothelial cells and assessing the possible cellular mechanisms involved. The effects of DKK1 on atherogenesis and plaque stability were evaluated in ApoE−/− mice using lentivirus injections to knockdown and knock-in the DKK1 gene. The presence of DKK1 resulted in enlarged and destabilized atherosclerotic lesions and increased apoptosis, while silencing of DKK1 alleviated plaque formation and vulnerability in the whole progression of atherosclerosis. DKK1 expression was upregulated in response to ox-LDL treatment in a time- and concentration-dependent manner on human umbilical vein endothelial cell (HUVEC). The interference of DKK1 reversed ox-LDL-induced apoptosis in HUVECs. The mechanism underlying this effect was DKK1’s activation of the JNK signal transduction pathway and inhibition of canonical Wnt signaling, following by activation of the IRE1α and eif2α/CHOP pathways. In conclusion, DKK1 promotes plaque formation and vulnerability partly by inducing apoptosis in endothelial cells, which partly through inducing the JNK-endoplasmic reticulum stress pathway and inhibiting canonical Wnt signaling.

Targeting Select Cellular Stress Pathways to Prevent Hyperglycemia-Related Complications: Shifting the Paradigm

Despite the advances made in preventing complications of diabetes, there is still substantial residual risk. Hence the need for developing new therapeutic agents that target the various facets of the pathogenesis of complications in people with diabetes. Traditionally four general biochemical pathways had been recognized as major contributors to glucotoxicity. These include the polyol pathway, the protein kinase C (PKC) pathway, glycosylation pathway, and oxidative stress. The latter has been proposed as a common impetus of the other pathways of glucotoxicity. More recently, the cross talk between oxidative stress and other recognized cellular stresses such as endoplasmic reticulum (ER), inflammatory, and mitochondrial stresses has emerged as an important additional mechanism of glucotoxicity. The observation that targeting oxidative stress with antioxidants has been associated with unfavorable clinical outcomes and the recognition that in cell cultures antioxidants may aggravate ER stress, suggests that selective targeting of individual cellular stresses may not be sufficient for preventing glucotoxicity. Future efforts should focus on developing therapeutic agents that can ameliorate cellular stress globally by simultaneously targeting the oxidative, ER, mitochondrial, and inflammatory stresses.

Therapeutic Targeting of Cellular Stress to Prevent Cardiovascular Disease: A Review of the Evidence

The availability of effective drugs targeting the major risk factors of cardiovascular disease (CVD) has reduced morbidity and mortality. Cumulative relative risk of CVD events can be reduced by 75 % with a combination of aspirin, a β-adrenoceptor antagonist (β-blocker), an HMG-CoA reductase inhibitor (statin), and an angiotensin-converting enzyme inhibitor. The principal pharmacodynamics of these drugs cannot explain the entirety of their cardioprotective action, as other drugs with similar pharmacologic targets have not been associated with favorable clinical effects. This raises the possibility that the cardioprotective drugs have a unique pleiotropic activity that contributes to their clinical efficacy. Recent data suggest that reducing cellular stress such as oxidative, inflammatory, and endoplasmic reticulum stress, might be a common denominator of the drugs with proven efficacy in reducing CVD risk. In this communication, the evidence in favor of this hypothesis is discussed, and ongoing trials with therapeutic agents targeting cellular stresses are reviewed.

Endoplasmic reticulum stress: a novel mechanism and therapeutic target for cardiovascular diseases

Endoplasmic reticulum is a principal organelle responsible for folding, post-translational modifications and transport of secretory, luminal and membrane proteins, thus palys an important rale in maintaining cellular homeostasis. Endoplasmic reticulum stress (ERS) is a condition that is accelerated by accumulation of unfolded/misfolded proteins after endoplasmic reticulum environment disturbance, triggered by a variety of physiological and pathological factors, such as nutrient deprivation, altered glycosylation, calcium depletion, oxidative stress, DNA damage and energy disturbance, etc. ERS may initiate the unfolded protein response (UPR) to restore cellular homeostasis or lead to apoptosis. Numerous studies have clarified the link between ERS and cardiovascular diseases. This review focuses on ERS-associated molecular mechanisms that participate in physiological and pathophysiological processes of heart and blood vessels. In addition, a number of drugs that regulate ERS was introduced, which may be used to treat cardiovascular diseases. This review may open new avenues for studying the pathogenesis of cardiovascular diseases and discovering novel drugs targeting ERS.