Hydrogen sulfide facilities production of nitric oxide via the Akt/endothelial nitric oxide synthases signaling pathway to protect human umbilical vein endothelial cells from injury by angiotensin II

Recent advances in the role of hydrogen sulfide in age-related diseases

In recent years, the impact of age-related diseases on human health has become increasingly severe, and developing effective drugs to deal with these diseases has become an urgent task. Considering the essential regulatory role of hydrogen sulfide (H2S) in these diseases, it is regarded as a promising target for treatment. H2S is a novel gaseous transmitter involved in many critical physiological activities, including anti-oxidation, anti-inflammation, and angiogenesis. H2S also regulates cell activities such as cell proliferation, migration, invasion, apoptosis, and autophagy. These regulatory effects of H2S contribute to relieving and treating age-related diseases. In this review, we mainly focus on the pathogenesis and treatment prospects of H2S in regulating age-related diseases.

FGFR2 modulates the Akt/Nrf2/ARE signaling pathway to improve angiotensin II-induced hypertension-related endothelial dysfunction

BACKGROUND

Fibroblast growth factor receptor (FGFR)2 expression was decreased in hypertension patients while its role in hypertension was not explored. This experiment aimed to investigate the expression ofFGFR2 in angiotensin II (Ang II)-induced human umbilical vein endothelial cells (HUVECs) and the role of FGFR2 in improving AngII-induced hypertension-related endothelial dysfunction.

METHODS

AngII-induced HUVECs simulated the hypertension model in vitro. The expression of FGFR2 in Ang II-induced HUVECs and transfected HUVECswas detected by RT-qPCR and western blot. The viability, apoptosis, migration and tube formation ability of Ang II-induced HUVECs were analyzed by Methyl Thiazolyl Tetrazolium (MTT) assay, flow cytometry analysis, wound healing assay and tube formation assay.Detectionof lactate dehydrogenase (LDH), caspase 3, Nitric Oxide (NO) and oxidative stress levels was conducted by assay kits and reactive oxygen species (ROS) level was detected by DCFH-DA assay. The expression of apoptosis-related proteins, protein kinase B(Akt)/nuclear factor E2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway-related proteins, phospho(p)-endothelial nitric oxide synthase (eNOS) and eNOS was determined by western blot.

RESULTS

The expression of FGFR2 was decreased in Ang II-induced HUVECs. FGFR2overexpression increased viability, suppressed apoptosis and oxidative stress, and improve endothelial dysfunction of AngII-induced HUVECs through activating the Akt/Nrf2/ARE signaling pathway. MK-2206 (Akt inhibitor) could weaken the effect of FGFR2overexpression to reduce viability, promote apoptosis and oxidative stress, and aggravate endothelial dysfunction of Ang II-inducedHUVECs.

CONCLUSION

Inconclusion, FGFR2activated the Akt/Nrf2/ARE signaling pathway to improve AngII-induced hypertension-related endothelial dysfunction.

Sex Influence on Autophagy Markers and miRNAs in Basal and Angiotensin II-Treated Human Umbilical Vein Endothelial Cells

Cardiovascular diseases (CVD) display many sex and gender differences, and endothelial dysfunction, angiotensin II (Ang II), and autophagy represent key factors in the autophagic process Therefore, we studied whether Ang II modulates the mentioned processes in a sex-specific way in HUVECs obtained from healthy male and female newborns. In basal HUVECs, the Parkin gene and protein were higher in FHUVECs than in MHUVECs, while the Beclin-1 protein was more expressed in MHUVECs, and no other significant differences were detected. Ang II significantly increases LAMP-1 and p62 protein expression and decreases the expression of Parkin protein in comparison to basal in MHUVECs. In FHUVECs, Ang II significantly increases the expression of Beclin-1 gene and protein, and Parkin gene. The LC3 II/I ratio and LAMP-1 protein were significantly higher in MHUVECs than in FHUVECs, while Parkin protein was significantly more expressed in Ang II-treated FHUVECs than in male cells. Ang II affects the single miRNA levels: miR-126-3p and miR-133a-3p are downregulated and upregulated in MHUVECs and FHUVECs, respectively. MiR-223 is downregulated in MHUVEC and FHUVECs. Finally, miR-29b-3p and miR-133b are not affected by Ang II. Ang II effects and the relationship between miRNAs and organelles-specific autophagy is sex-dependent in HUVECs. This could lead to a better understanding of the mechanisms underlying sex differences in endothelial dysfunction, providing useful indications for innovative biomarkers and personalized therapeutic approaches.

ACE Inhibitory Peptide from Skin Collagen Hydrolysate of Takifugu bimaculatus as Potential for Protecting HUVECs Injury

Angiotensin-I-converting enzyme (ACE) is a crucial enzyme or receptor that catalyzes the generation of potent vasopressor angiotensin II (Ang II). ACE inhibitory peptides from fish showed effective ACE inhibitory activity. In this study, we reported an ACE inhibitory peptide from Takifugu bimaculatus (T. bimaculatus), which was obtained by molecular docking with acid-soluble collagen (ASC) hydrolysate of T. bimaculatus. The antihypertensive effects and potential mechanism were conducted using Ang-II-induced human umbilical vein endothelial cells (HUVECs) as a model. The results showed that FNLRMQ alleviated the viability and facilitated apoptosis of Ang-II-induced HUVECs. Further research suggested that FNLRMQ may protect Ang-II-induced endothelial injury by regulating Nrf2/HO-1 and PI3K/Akt/eNOS signaling pathways. This study, herein, reveals that collagen peptide FNLRMQ could be used as a potential candidate compound for antihypertensive treatment, and could provide scientific evidence for the high-value utilization of marine resources including T. bimaculatus.

Hydrogen sulfide reduces the activity of human endothelial cells

INTRODUCTION

The volatile endogenous mediator hydrogen sulfide (H2S) is known to impair thrombus formation by affecting the activity of human platelets. Beside platelets and coagulation factors the endothelium is crucial during thrombogenesis.

OBJECTIVE

This study evaluates the effect of the H2S donor GYY4137 (GYY) on human umbilical vein endothelial cells (HUVECs) in vitro.

METHODS

Flow cytometry of resting, stimulated or GYY-treated and subsequently stimulated HUVECs was performed to analyse the expression of E-selectin, ICAM-1 and VCAM-1. To study a potential reversibility of the GYY action, E-selectin expression was further assessed on HUVECs that were stimulated 24 h after GYY exposure. A WST-1 assay was performed to study toxic effects of the H2S donor. By using the biotin switch assay, protein S-sulfhydration of GYY-exposed HUVECs was assessed. Further on, the effects of GYY on HUVEC migration and von Willebrand factor (vWF) secretion were assessed.

RESULTS

GYY treatment significantly reduced the expression of E-selectin and ICAM-1 but not of VCAM-1. When HUVECs were stimulated 24 h after GYY treatment, E-selectin expression was no longer affected. The WST-1 assay revealed no effects of GYY on endothelial cell viability. Furthermore, GYY impaired endothelial migration, reduced vWF secretion and increased protein S-sulfhydration.

CONCLUSIONS

Summarizing, GYY dose dependently and reversibly reduces the activity of endothelial cells.

Gastrodin prevents homocysteine-induced human umbilical vein endothelial cells injury via PI3K/Akt/eNOS and Nrf2/ARE pathway

In this study, we investigated the protective effects of gastrodin (Gas) against homocysteine‐induced human umbilical vein endothelial cell (HUVEC) injury and the role of the phosphoinositide 3‐kinase (PI3K)/threonine kinase 1 (Akt)/endothelial nitric oxide synthase (eNOS) and NF‐E2‐related factor 2 (Nrf2)/antioxidant response element (ARE) pathways. We stimulated cells with homocysteine (1 mmol/L, 24 hours) and tested the effects of gastrodin (200‐800 μg/mL) on cell viability and the production of malondialdehyde (MDA), lactate dehydrogenase (LDH) and reactive oxygen species (ROS). Then, Nrf2 distribution in the cytoplasm and nucleus as well as the expression of enzymes downstream of Nrf2 was determined. Furthermore, we analysed the expression of bax, bcl‐2 and cleaved caspase3, and assessed the involvement of the PI3K/Akt/eNOS pathway by Western blots. Finally, we tested the vasoactive effect of gastrodin in thoracic aortic rings. The results showed that gastrodin decreased MDA, LDH and ROS production and increased cell viability, NO production and relaxation of thoracic aortic rings. Moreover, the protective effects of Gas on NO production and relaxation of thoracic aortic rings were blocked by L‐NAME but enhanced by Cav‐1 knockdown, and MK‐2206 treatment abolished the effect of Gas on the ROS. In addition, treatment with gastrodin increased Nrf2 nuclear translocation, thus enhancing the expression of downstream enzymes. Finally, gastrodin increased the expression of PI3K, p‐Akt, and eNOS and decreased Cav‐1 protein expression. In conclusion, our study suggested that gastrodin may protect HUVECs from homocysteine‐induced injury, and the PI3K/Akt/eNOS and Nrf2/ARE pathways may be responsible for the efficacy of gastrodin.

Regulation of carbohydrate metabolism by nitric oxide and hydrogen sulfide: Implications in diabetes

Nitric oxide (NO) and hydrogen sulfide (H₂S) are two gasotransmitters that are produced in the human body and have a key role in many of the physiological activities of the various organ systems. Decreased NO bioavailability and deficiency of H₂S are involved in the pathophysiology of type 2 diabetes and its complications. Restoration of NO levels have favorable metabolic effects in diabetes. The role of H₂S in pathophysiology of diabetes is however controversial; H₂S production is decreased during development of obesity, diabetes, and its complications, suggesting the potential therapeutic effects of H₂S. On the other hand, increased H₂S levels disturb the pancreatic β-cell function and decrease insulin secretion. In addition, there appear to be important interactions between NO and H₂S at the levels of both biosynthesis and signaling pathways, yet clear an insight into this relationship is lacking. H₂S potentiates the effects of NO in the cardiovascular system as well as NO release from its storage pools. Likewise, NO increases the activity and the expression of H₂S-generating enzymes. Inhibition of NO production leads to elimination/attenuation of the cardioprotective effects of H₂S. Regarding the increasing interest in the therapeutic applications of NO or H₂S-releasing molecules in a variety of diseases, particularly in the cardiovascular disorders, much is to be learned about their function in glucose/insulin metabolism, especially in diabetes. The aim of this review is to provide a better understanding of the individual and the interactive roles of NO and H₂S in carbohydrate metabolism.

A novel role of sONE/NOS3/NO signaling cascade in mediating hydrogen sulphide bilateral effects on triple negative breast cancer progression

Hydrogen sulphide (H₂S) gas has been recognized as an intracellular mediator influencing an array of signaling pathways. Yet, the role of H₂S in cancer progression has been controversial. This study aims to unravel the role of exogenous H₂S in triple negative breast cancer (TNBC) and to further investigate any possible association of H₂S mediated actions with the endogenous production of nitric oxide (NO) gas. A wide concentration range of NaHS (20-2000 μM) and a variable reaction time (2-72 h) were probed. A bell-shaped impact of H₂S on TNBC cellular viability, proliferation, migration, invasion and colony forming ability was repeatedly observed in the aggressive TNBC cell lines, MDA-MB-231 but not in hormone receptor positive, MCF-7 cells. This bell-shaped effect was found to be shifted towards the left upon increasing the reaction time within the range of 2-24 h. However, this was totally opposed in case of continuous exposure (72 h) to exogenous H₂S. An inverted bell-shaped effect of H₂S on TNBC cellular growth, migration, proliferation and colony forming ability was shown. Moreover, this study provided the first evidence of a possible involvement of NO in mediating H₂S actions in TNBC. Such intricate cross-talk was found to be orchestrated by the novel lncRNA, sONE and its down-stream target NOS3 building up a novel axis, sONE/NOS3/NO, that was shown to play a pivotal role in plotting the bilateral effect of H₂S on TNBC progression. Finally, this study showed that low and continuous exposure of H₂S serves as a novel, selective and effective strategy in harnessing TNBC oncogenic profile through cGMP dependent and independent pathways where alterations of cell cycle regulatory proteins such as TP53 and c-Myc was observed. Moreover, NaHS could repress TNBC migration and invasion capacities through repressing the intracellular adhesion molecule, ICAM-1. In conclusion, this study provides an insight about the role of exogenous H₂S in TNBC cell lines highlighting a novel crosstalk between H₂S and NO orchestrated by sONE/NOS3 axis.

Regulation of vascular tone homeostasis by NO and H2S: Implications in hypertension

Nitric oxide (NO) and hydrogen sulfide (H2S) are two gasotransmitters that are produced in the vasculature and contribute to the regulation of vascular tone. NO and H2S are synthesized in both vascular smooth muscle and endothelial cells; NO functions primarily through the sGC/cGMP pathway, and H2S mainly through activation of the ATP-dependent potassium channels; both leading to relaxation of vascular smooth muscle cells. A deficit in the NO/H2S homeostasis is involved in the pathogenesis of various cardiovascular diseases, especially hypertension. It is now becoming increasingly clear that there are important interactions between NO and H2S and that have a profound impact on vascular tone and this may provide insights into the new therapeutic interventions. The aim of this review is to provide a better understanding of individual and interactive roles of NO and H2S in vascular biology. Overall, available data indicate that both NO and H2S contribute to vascular (patho)physiology and in regulating blood pressure. In addition, boosting NO and H2S using various dietary sources or donors could be a hopeful therapeutic strategy in the management of hypertension.