Recombinant human brain natriuretic peptide attenuates ischemic brain injury in mice by inhibiting oxidative stress and cell apoptosis via activation of PI3K/AKT/Nrf2/HO-1 pathway

Ischemic stroke followed by cerebral artery occlusion is a main cause of chronic disability worldwide. Recombinant human brain natriuretic peptide (rhBNP) has been reported to alleviate sepsis-induced cognitive dysfunction and brain I/R injury. However, the function and molecular mechanisms of rhBNP in ischemic brain injury have not been clarified. For establishment of an animal model of ischemic brain injury, C57BL/6 mice were treated with middle cerebral artery occlusion (MCAO) surgery for 1 h and reperfusion for 24 h. After subcutaneous injection of rhBNP into model mice, neurologic deficits were assessed by evaluating behavior of mice according to Longa scoring system, and TTC staining was utilized to determine the brain infarct size of mice. The levels of oxidative stress markers, superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and malondialdehyde (MDA), were detected in hippocampal tissues of mice by corresponding kits. Cell apoptosis in hippocampus tissues was examined by TUNEL staining. Protein levels of antioxidant enzymes (HO-1 and NQO1) in cerebral cortex, apoptotic markers (Bax, Bcl-2, and cleaved caspase), and PI3K/AKT pathway-associated factors in hippocampus were tested by western blot analysis. The results revealed that injection of rhBNP decreased neurologic deficit scores, the percent of brain water content, and infarct volume. Additionally, rhBNP downregulated MDA level, upregulated the levels of SOD, CAT, and GSH in hippocampus of mice, and increased protein levels of HO-1 and NQO1 in the cortex. Cell apoptosis in hippocampus tissues of model mice was inhibited by rhBNP which was shown as the reduced TUNEL-positive cells, the decreased Bax, cleaved caspase-3, and cleaved caspase-9 protein levels, and the enhanced Bcl-2 protein level. In addition, rhBNP treatment activated the PI3K/AKT signaling pathway and upregulated the protein levels of HO-1 and NRF2. Overall, rhBNP activates the PI3K/AKT/HO-1/NRF2 pathway to attenuate ischemic brain injury in mice after MCAO by suppression of cell apoptosis and oxidative stress.

A meta-analysis of the clinical efficacy of rhBNP in treating patients with acute myocardial infarction and heart failure

OBJECTIVE

To explore the clinical efficacy of rhBNP in patients with acute myocardial infarction (AMI) and heart failure (HF).

METHODS

A systematic review and a meta-analysis were performed using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. On May 30, 2020, we consulted the electronic databases PubMed, EBSCO, Elsevier, Springer, Wiley, and Cochrane using the keywords "acute coronary syndrome (ACS)", "brain natriuretic peptide (BNP)", and "acute myocardial infarction (AMI)". The quality of the data included in the study was assessed according to the Cochrane Handbook for Systematic Reviews of Interventions. The results of the clinical randomized controlled study reports were analyzed using Review Manager 5.1.0.

RESULTS

A total of nine, clinical, randomized, controlled studies were included. The effective rate in the rhBNP group was significantly higher than it was in the control group (Z = 9.50, P < 0.00001). The patients in the rhBNP group showed remarkably shorter hospital stays (Z = 24.43, P < 0.00001) and markedly increased left ventricular ejection fractions (LVEF) (Z = 245.53, P < 0.00001). Compared with the LVEF in the control group, the LVEF in the rhBNP group was significantly increased (Z = 3.55, P = 0.0004), but the rate of cardiac hypotension (Z = 3.55, P = 0.0004) and the headache incidence rate in the rhBNP group (Z = 2.3, P = 0.04) were not elevated. The rhBNP group showed no increase in either the low heart rate (Z = 1.22, P = 0.22) or the rate of renal insufficiency (Z = 0.35, P = 0.73).

CONCLUSION

The meta-analysis suggests that, compared with the conventional treatment of patients with AMI and HF, rhBNP can markedly improve the clinical efficacy and myocardial functions and shorten the hospital stays, without elevating the rate of adverse reactions, such as hypotension, headaches, low heart rate, and renal insufficiency.

Beneficial effects of early administration of recombinant human B-type natriuretic peptide in ST-elevation myocardial infarction patients receiving percutaneous coronary intervention treatment

INTRODUCTION

We aimed to evaluate the clinical performance of early administration of recombinant human B-type natriuretic peptide (rhBNP) to ST-elevation myocardial infarction (STEMI) patients receiving percutaneous coronary intervention (PCI) treatment.

METHODS

In total, 185 patients diagnosed with STEMI were enrolled and randomised into either the placebo-treated (n = 88) or rhBNP-treated (n = 97) group. Patients were given either saline or rhBNP ten minutes before PCI and monitored with various cardiac parameters, including accelerated idioventricular rhythm, frequent ventricular premature beat (FVPB), ventricular tachycardia, systolic blood pressure, thrombolysis in myocardial infarction (TIMI) 3 gradation, corrected TIMI frame count (cTFC) and myocardial blush grade (MBG) 3 classification.

RESULTS

Our results revealed no difference in accelerated idioventricular rhythm between the two groups. However, FVPB and ventricular tachycardia were significantly decreased in rhBNP-treated patients compared to placebo-treated patients (p < 0.05). Moreover, the occurrence ratio of reperfusion-associated low blood pressure in rhBNP-treated patients was lower than in placebo-treated patients (p = 0.03), while no difference was observed in infarction-related arteries TIMI 3 blood flow between the two groups (p = 0.23). Importantly, measurement of post-reperfusion blood flow velocity via cTFC suggested that rhBNP treatment could significantly increase blood circulation (p = 0.003). After stent implantation, the acquisition rate of MBG 3 was higher in rhBNP-treated patients compared to placebo-treated patients (p = 0.071), although the difference was not significant.

CONCLUSION

We concluded that early administration of rhBNP can ameliorate the severity of reperfusion injury for STEMI patients receiving PCI treatment.

Effect of rhBNP on renal function in STEMI-HF patients with mild renal insufficiency undergoing primary PCI

This study aims to investigate the effect of recombinant human brain natriuretic peptide (rhBNP) on renal function and contrast-induced nephropathy (CIN) incidence in ST-segment elevation myocardial infarction and heart failure (STEMI-HF) patients with mild renal insufficiency undergoing primary percutaneous coronary intervention (PCI). A total of 116 participants were randomized into rhBNP (rhBNP, n = 57) and nitroglycerin group (NIT, n = 59), receiving intravenous rhBNP or nitroglycerin from admission to 72 h after PCI. Renal function was assessed by serum creatinine (SCr), estimated glomerular filtration rate (eGFR), Cystatin-C (Cys-C) and β2-microglobulin before and after primary PCI, and calculated the incidence of CIN within 72 h after PCI. There were no significant differences in SCr, eGFR and β2-microglobulin between the two groups (P > 0.05, respectively). Compared with the NIT group, the total urinary volume within 72 h was higher while the level of Cys-C at 24 and 72 h after PCI was lower in the rhBNP group. rhBNP was associated with a decline in the incidence of CIN (12.28 vs. 28.81 %, P < 0.05). No differences were detected in mortality and re-hospitalization in 3 months between the two groups. The incidence of renal injury was not different between rhBNP and nitroglycerin in STEMI-HF patients with mild renal insufficiency. However, infusion of rhBNP was associated with a decline in incidence of CIN.