Endoplasmic reticulum stress markers are of no value in predicting cardiopulmonary resuscitation success and survival in out-of hospital cardiac arrest: A nested case-control study

High GRP78 levels in Covid-19 infection: A case-control study

Introduction

Covid-19 infection was declared a global pandemic by WHO on March 11, 2020. GRP78 protein is known to be involved in the intrusion of numerous viruses. Our current study tries to provide some insight into the variation of GRP78 protein levels in patients with Covid-19 (−) pneumonia, Covid-19 (+) pneumonia, and CT negative Covid-19 infection in comparison to the normal population through a larger number of cases.

Materials and methods

42 patients who have Covid-19 (−) pneumonia; 72 patients who have Covid-19 infection (30 pneumonia,42 CT negative patients) and 30 patient who have no known diseases (control group) have included in the study after the clinical and radiological evaluation. Serum GRP78 levels of the subjects were measured through a commercially available enzyme-linked immunosorbent assay (ELISA) kit.

Results

The GRP78 level was found to be significantly higher in the Covid-19 infection group than both Covid-19 (−) pneumonia and control group (p = 0.031 and p = 0.0001, respectively).No significant difference was evident between Covid-19 (−) pneumonia, Covid-19 (+) pneumonia and CT negative Covid 19 infection groups with respect to GRP78 levels (p = 0.09). In addition, the GRP78 levels were significantly higher in the Covid-19 (−) pneumonia group than the control group (p = 0.0001).

Conclusion

This prospective case-control study reveals that the serum GRP78 levels significantly increased during Covid-19 infection in comparison to both the Covid-19 (−) pneumonia and the control group. As the association between SARS-CoV-2 virus and GRP78 protein is revealed more clearly, this association may come to the fore as a therapeutic target.

Predictive Value of Endoplasmic Reticulum Stress Markers in Low Ejection Fractional Heart Failure

BACKGROUND/AIM

Endoplasmic reticulum (ER) stress plays a critical role in the development of cardiac hypertrophy and heart failure. Heart failure is a crucial health problem that affects 23 million people worldwide, causes approximately 2.4 million people to be hospitalized every year in the USA, and leads to the death of more than 300,000 people. In this study, we aimed to investigate the clinical significance of ER stress markers and the predictive value of acute decompensated heart failure in patients with low ejection fraction heart failure (ADHF).

PATIENTS AND METHODS

This is a prospective case control study. The data included laboratory parameters pertaining to patients with ADHF in the emergency service and lipid parameters obtained during their admission to the hospital. In addition, the same parameters obtained from the control group patients with chronic heart failure (CHF) during their routine polyclinic control were recorded in the data set. Admission time to the hospital and length of hospital stay were included in the data. The levels of glucose regulated protein (GRP78), protein kinase RNA-like endoplasmic reticulum kinase (PERK), and C/EBP homologous protein (CHOP) in peripheral blood serum obtained from the patients and the control group were measured using the ELISA method.

RESULTS

Serum GRP78 concentration was lower in the HF group (p=0.003) compared to the control. The median value of serum PERK concentration in the HF group was higher than that of the control group (573 pg/ml, IQR=477.5-650 vs. 495.5 pg/ml, IQR=294-648, respectively) (p=0.001). However, there were no statistically significant differences in GRP78 and PERK serum concentrations between ADHF and CHF subgroups. Receiver operating characteristic (ROC) curve analysis showed greater area under the curve (AUC) for the serum GRP78 levels of the healthy individuals (AUC=0.748, 95% CI=0.681-0.814, p=0.0003). The serum GRP78 level was found to be 80% sensitive and 70% specific at 147.5 pg/ml (p=0.0003) for distinguishing healthy individuals from HF patients. In the ADHF subgroup, there was a moderate correlation between hospitalization time and serum CHOP concentrations (Spearman rho=0.586 and p=0.001).

CONCLUSION

High GRP78 serum concentration may protect the patient from ER stress. In addition, the serum PERK level is high in patients with HF, whereas it is insufficient in predicting acute decompensation. CHOP may be useful in predicting the length of hospital stay in patients with ADHF.

Exendin-4 regulates endoplasmic reticulum stress to protect endothelial progenitor cells from high-glucose damage

BACKGROUND

High glucose affects the function of endothelial cells by increasing oxidative stress. Studies have found that exendin-4 can improve wound healing in diabetic mice and mice with normal blood glucose. However, the mechanism of exendin-4 in endothelial progenitor cells under high-glucose condition has not been fully elucidated.

METHODS

Diabetic mouse models were established to investigate the effects of exendin-4 on endothelial progenitor cells in diabetic mice. Serum superoxide dismutase (SOD) and malondialdehyde (MDA) were determined by WST-8 and thiobarbituric acid (TBA) colorimetry, respectively. Cell viability, apoptosis and reactive oxygen species (ROS) were detected by 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) and flow cytometry. Gene and protein expressions were determined by Quantitative reverse transcription PCR (qRT-PCR) assay and Western blot (WB).

RESULTS

The results showed that in diabetic mice, exendin-4 did not affect blood glucose or body weight, moreover, it improved aortic diastolic function, increased SOD activity and down-regulated malondialdehyde (MDA) level in the mice. In addition, exendin-4 also increased endothelial progenitor cell (EPCs) viability and reduced cell apoptosis through inhibiting p38 MAPK pathway and reducing endoplasmic reticulum stress and ROS.

CONCLUSION

Exndin-4 can alleviate diabetes-caused damage to mice, moreover, it reduced endoplasmic reticulum stress and ROS through inhibiting p38 MAPK pathway in MPCs cells under high-glucose condition, thus increasing cell viability and reducing cell apoptosis.