Serum heat shock protein 27 levels predict cardiac mortality in hemodialysis patients

Impact of vitamin D supplementation on modulating heat-shock proteins in postmenopausal women: a randomized, double-blind, placebo-controlled study

OBJECTIVE

The aim of this study was to examine the effect of vitamin D (VitD) supplementation on serum heat-shock proteins (HSP) in postmenopausal women (PW).

METHODS

In this double-blind, placebo-controlled trial, 160 PW aged 45 to 65 years with amenorrhea 12 months or more were randomized into two groups: 80 PW in VitD group (oral supplementation with 1,000 IU VitD 3 /d) or 80 PW in placebo group. The PW were assessed at baseline and after 10 months of intervention. Plasma concentrations of 25-hydroxyVitD (25[OH]D) were measured by high-performance liquid chromatography. HSP27/pS78/pS82, HSP27/total, HSP60, HSP70/72, and HSP90α levels were assessed in serum using a multiplexed bead immunoassay.

RESULTS

HSP27 (pS78/pS82 [ P < 0.035] and total [ P < 0.001]) levels increased in the supplemented group when compared with the control group. There was no effect of VitD supplementation on HSP60, HSP70/72, and HSP90α levels.

CONCLUSIONS

Vitamin D supplementation increases serum HSP27 level in PW.

Mechanistic insights into heat shock protein 27, a potential therapeutic target for cardiovascular diseases

Heat shock protein 27 (HSP27) is a small chaperone protein that is overexpressed in a variety of cellular stress states. It is involved in regulating proteostasis and protecting cells from multiple sources of stress injury by stabilizing protein conformation and promoting the refolding of misfolded proteins. Previous studies have confirmed that HSP27 is involved in the development of cardiovascular diseases and plays an important regulatory role in this process. Herein, we comprehensively and systematically summarize the involvement of HSP27 and its phosphorylated form in pathophysiological processes, including oxidative stress, inflammatory responses, and apoptosis, and further explore the potential mechanisms and possible roles of HSP27 in the diagnosis and treatment of cardiovascular diseases. Targeting HSP27 is a promising future strategy for the treatment of cardiovascular diseases.

Host cell stress response as a predictor of COVID-19 infectivity and disease progression

The coronavirus disease (COVID-19) caused by a coronavirus identified in December 2019 has caused a global pandemic. COVID-19 was declared a pandemic in March 2020 and has led to more than 6.3 million deaths. The pandemic has disrupted world travel, economies, and lifestyles worldwide. Although vaccination has been an effective tool to reduce the severity and spread of the disease there is a need for more concerted approaches to fighting the disease. COVID-19 is characterised as a severe acute respiratory syndrome . The severity of the disease is associated with a battery of comorbidities such as cardiovascular diseases, cancer, chronic lung disease, and renal disease. These underlying diseases are associated with general cellular stress. Thus, COVID-19 exacerbates outcomes of the underlying conditions. Consequently, coronavirus infection and the various underlying conditions converge to present a combined strain on the cellular response. While the host response to the stress is primarily intended to be of benefit, the outcomes are occasionally unpredictable because the cellular stress response is a function of complex factors. This review discusses the role of the host stress response as a convergent point for COVID-19 and several non-communicable diseases. We further discuss the merits of targeting the host stress response to manage the clinical outcomes of COVID-19.

Heat Shock Protein 27 Levels Predict Myocardial Inhomogeneities in Hemodialysis Patients

Background

Sudden cardiac death (SCD) is the single major cause of death in hemodialysis (HD) patients. QRS-T angle is an established marker of global repolarization heterogeneity associated with electrical instability and SCD. Heat shock protein 27 (HSP27) plays an important, protective role against noxious factors in the cardiovascular (CV) system. This study is aimed at assessing whether low HSP27 is associated with myocardial inhomogeneities in HD patients, as expressed by increases in the spatial QRS-T angle.

Methods

Clinical data and biochemical, echocardiographic, and electrocardiographic parameters were evaluated in 182 HD patients. Patients were split into normal and abnormal QRS-T angle groups.

Results

Patients with abnormally high QRS-T angles were older and had higher prevalence of diabetes as well as myocardial infarction, higher left ventricular mass index (LVMI) and C-reactive protein, worse oxidant/antioxidant status, and lower ejection fraction and HSP27. Multiple regression analysis revealed that abnormal QRS-T values were independently, negatively associated with serum HSP27 and positively associated with LVMI.

Conclusions

Low HSP27 levels are associated with increased heterogeneity of myocardial action potential, as expressed by increased spatial QRS-T angle.

Predictive role of C-reactive protein in sudden death: a meta-analysis of prospective studies

Objective

C-reactive protein (CRP) is a powerful predictor of and risk factor for cardiovascular disease. However, the relationship between CRP and sudden death (SD) is controversial. Therefore, we performed a meta-analysis to evaluate the association between CRP and SD.

Methods

We conducted a comprehensive search of the databases of PubMed, Web of Science, Embase, Cochrane Library, Wanfang, CNKI, China Biology Medicine disc, and Weipu. Two researchers independently screened the literature, extracted data, and evaluated the data quality. The overall effect size was meta-analyzed using Stata software version 12.0 (StataCorp, College Station, TX, USA).

Results

Twelve prospective studies involving 36,646 patients were included in the present meta-analysis. The data revealed that patients with higher CRP concentrations had a greater risk of SD (hazard ratio, 1.19; 95% confidence interval, 1.09–1.29). When the hazard ratio of SD was calculated by multivariate analysis of nine studies, CRP was confirmed to be an independent predictive factor for SD (hazard ratio, 1.05; 95% confidence interval, 1.03–1.07).

Conclusions

This meta-analysis confirmed that CRP is an independent predictor of SD. These results support the recommendation of recording the CRP concentration for risk assessment of SD in clinical practice.

Heat Shock Proteins: Connectors between Heart and Kidney

Over the development of eukaryotic cells, intrinsic mechanisms have been developed in order to provide the ability to defend against aggressive agents. In this sense, a group of proteins plays a crucial role in controlling the production of several proteins, guaranteeing cell survival. The heat shock proteins (HSPs), are a family of proteins that have been linked to different cellular functions, being activated under conditions of cellular stress, not only imposed by thermal variation but also toxins, radiation, infectious agents, hypoxia, etc. Regarding pathological situations as seen in cardiorenal syndrome (CRS), HSPs have been shown to be important mediators involved in the control of gene transcription and intracellular signaling, in addition to be an important connector with the immune system. CRS is classified as acute or chronic and according to the first organ to suffer the injury, which can be the heart (CRS type 1 and type 2), kidneys (CRS type 3 and 4) or both (CRS type 5). In all types of CRS, the immune system, redox balance, mitochondrial dysfunction, and tissue remodeling have been the subject of numerous studies in the literature in order to elucidate mechanisms and propose new therapeutic strategies. In this sense, HSPs have been targeted by researchers as important connectors between kidney and heart. Thus, the present review has a focus to present the state of the art regarding the role of HSPs in the pathophysiology of cardiac and renal alterations, as well their role in the kidney–heart axis.

Circulating chaperones in patients with aortic valve stenosis undergoing TAVR: impact of concomitant chronic kidney disease

Chronic kidney disease (CKD) is a frequent comorbidity of aortic valve stenosis (AVS). Circulating chaperones have emerged as both effectors and prognostic markers for various diseases. We investigated the role of circulating chaperones in patients with severe AVS undergoing transcatheter aortic valve replacement (TAVR). In this observational cohort study, 159 consecutive patients undergoing TAVR were included and serum levels of Glucose-regulated protein 78 (GRP78) and heat shock protein 27 (HSP27) were measured by ELISA. The primary end point was defined as 1-year mortality. Patients with lower levels of circulating GRP78 (<1347 ng/mL) had an increased 1-year mortality rate compared to patients with higher levels of GRP78 (25.0% vs 10.3%, P = 0.026). GRP78 was associated with lower 1-year mortality in a univariate analysis (HR 0.354, P = 0.047). After adjusting for age, sex, several comorbidities and biomarkers, GRP78 (HR 0.295, P = 0.024) and CKD (HR 2.809, P = 0.044) remained independent predictors of the primary end point of 1-year mortality in a multivariate analysis. Patients with concomitant CKD had significantly higher levels of HSP27 compared to patients without CKD (1690 pg/mL vs 1076 pg/mL, P = 0.0109). In patients with CKD, elevated HSP27 was identified as a protective marker (1-year mortality: 9.6% vs 31.4%, log-rank P = 0.0166). Using cut-off values for GRP78 and HSP27 we were able to stratify patients with CKD undergoing TAVR into 4 groups with distinct mortality rates (50% vs 22.2% vs 24% vs 7.9%, log-rank P = 0.0170). GRP78 is an overall predictor of mortality after TAVR, while the combination of GRP78 and HSP27 helps to predict mortality in patients with CKD receiving TAVR.

Heat Shock Protein 27 Is an Emerging Predictor of Contrast-Induced Acute Kidney Injury on Patients Subjected to Percutaneous Coronary Interventions

Contrast-induced acute kidney injury (CI-AKI) is a serious complication associated with considerable morbidity and mortality. Heat-shock protein 27 (HSP27) plays a role in the defense of the kidney tissue against various forms of cellular stress, including hypoxia and oxydative stress, both features associated with CI-AKI. The aim of our study was to evaluate a potential predictive value of HSP27 for CI-AKI in patients subjected to percutaneous coronary interventions (PCI). Included were 343 selected patients subjected to PCI. Exclusion criteria were conditions that potentially might influence HSP27 levels. HSP27 serum levels were evaluated prior to PCI, together with serum creatinine, the concentration of which was also evaluated twice at 48 and 72 h post PCI. CI-AKI was diagnosed in 9.3% of patients. Patients in whom CI-AKI was diagnosed were older (p < 0.001), were more often females (p = 0.021), had higher prevalence of diabetes (p = 0.011), hypotension during PCI (p < 0.001), albuminuria (p = 0.004) as well as multivessel disease (p = 0.002), received higher contrast volume (p = 0.006), more often received contrast volume (CV) above the maximum allowed contrast dose (MACD) (p < 0.001), and had lower HSP27 level (p < 0.001). On multivariate analysis, CV > MACD (OR 1.23, p = 0.001), number of diseased vessels (OR 1.27, p = 0.006), and HSP27 (OR 0.81, p = 0.001) remained independent predictors of CI-AKI. Low concentration of HSP27 is an emerging, strong and independent predictor of CI-AKI in patients subjected to PCI.

Apoptosis, autophagy and atherosclerosis: Relationships and the role of Hsp27

Atherosclerosis is a multifactorial chronic inflammatory disease of the arterial wall, and an important pathological basis of coronary heart disease. Endothelial cells, vascular smooth muscle cells, and macrophages play important roles in the development of atherosclerosis. Of note, apoptosis and autophagy, two types of programmed cell death, influence the development and progression of atherosclerosis via the modulation of such cells. The small heat shock protein Hsp27 is a multifunctional protein induced by various stress factors and has a protective effect on cells. A large number of studies have demonstrated that Hsp27 plays an important role in regulating apoptosis. Recently, some studies have suggested that Hsp27 also participates in the autophagic process. Moreover, Hsp27 is closely related to the occurrence and development of atherosclerosis. Here, we summarize the molecular mechanisms of apoptosis and autophagy and discuss their effects on endothelial cells, vascular smooth muscle cells, and macrophages in the context of atherosclerotic procession. We further explore the involvement of Hsp27 in apoptosis, autophagy, and atherosclerosis. We speculate that Hsp27 may exert its anti-atherosclerotic role via the regulation of apoptosis and autophagy; this may provide the basis for the development of new approaches for the prevention and treatment of atherosclerosis.

Neutrophil-Lymphocyte Ratio (NLR) Reflects Myocardial Inhomogeneities in Hemodialyzed Patients

Introduction

Cardiovascular diseases (CVDs) are a leading cause of death in chronically hemodialyzed (HD) patients. In this group, inflammation exerts significant impact on the prevalence of CVD morbidity and mortality. Spatial QRS-T angle is an independent and strong predictor of CV events, including sudden cardiac death (SCD), both in general population and HD patients. Pathogenesis of widened QRS-T angle is complicated and is not well established.

Objectives

The study is aimed at evaluating whether inflammation process can contribute to the wide QRS-T angle. Patients and Methods. The retrospective study was performed on 183 HD patients. The control group consisted of 38 patients. Demographic, biochemical, vectorcardiographic, and echocardiographic data were evaluated in all patients. Inflammation process was expressed as neutrophil-lymphocyte ratio (NLR), as well as C-reactive protein (CRP).

Results

Both NLR (3.40 vs. 1.95 (p < 0.0001)) and spatial QRS-T angle (50.76 vs. 93.56 (p < 0.001)) were higher in the examined group, compared to the control group. Similarly, CRP was higher in the examined group than in the control group (8.35 vs. 4.06 (p < 0.001), respectively). The QRS-T angle correlated with NLR, CRP, some structural echocardiographic parameters, parathormone (PTH), and calcium (Ca) concentrations. Multiple regression analysis showed that NLR is an independent QRS-T angle predictor (r = 0.498, p = 0.0027). The ROC curve analysis indicated the cut-off point of NLR equaled 4.59, where the sensitivity and specificity were the highest for predicting myocardial inhomogeneities expressed as widened QRS-T angle.

Conclusion

The NLR, as an inflammation marker, may indicate myocardial inhomogeneities in HD patients.

Intermittent Hypoxic Exposure Reduces Endothelial Dysfunction

Intermittent exposure to hypoxia (IHE) increases the production of reactive oxygen and nitrogen species as well as erythropoietin (EPO), which stimulates the adaptation to intense physical activity. However, several studies suggest a protective effect of moderate hypoxia in cardiovascular disease (CVD) events. The effects of intense physical activity with IHE on oxi-inflammatory mediators and their interaction with conventional CVD risk factors were investigated. Blood samples were collected from elite athletes (control n = 6, IHE n = 6) during a 6-day IHE cycle using hypoxicator GO2 altitude. IHE was held once a day, at least 2 hours after training. In serum, hydrogen peroxide (H₂O₂), nitric oxide (NO), 3-nitrotyrosine (3-Nitro), proinflammatory cytokines (IL-1β and TNFα), high sensitivity C-reactive protein (hsCRP), and heat shock protein 27 (HSP27) were determined by the commercial immunoenzyme (ELISA kits) or colorimetric methods. Serum erythropoietin (EPO) level was measured by ELISA kit every day of hypoxia. IHE was found to significantly increase H₂O₂, NO, and HSP27 but to decrease 3NT concentrations. The changes in 3NT and HSP27 following hypoxia proved to enhance NO bioavailability and endothelial function. In the present study, the oxi-inflammatory mediators IL-1β and hsCRP increased in IHE group but they did not exceed the reference values. The serum EPO level increased on the 3^rd day of IHE, then decreased on 5^th day of IHE, and correlated with NO/H₂O₂ ratio (r _s = 0.640, P < 0.05). There were no changes in haematological markers contrary to lipoproteins such as low-density lipoprotein (LDL) and non-high-density lipoprotein (non-HDL) which showed a decreasing trend in response to hypoxic exposure. The study demonstrated that IHE combined with sports activity reduced a risk of endothelial dysfunction and atherogenesis in athletes even though the oxi-inflammatory processes were enhanced. Therefore, 6-day IHE seems to be a potential therapeutic and nonpharmacological method to reduce CVD risk, especially in elite athletes participating in strenuous training.