The activation of histone deacetylases 4 prevented endothelial dysfunction: A crucial mechanism of HuangqiGuizhiWuwu Decoction in improving microcirculation dysfunction in diabetes

Fenugreek extract improves diabetes-induced endothelial dysfunction via the arginase 1 pathway

Endothelial dysfunction (ED) is an initiating trigger and key factor in vascular complications, leading to disability and mortality in individuals with diabetes. The research concerning therapeutic interventions for ED has gained considerable interest. Fenugreek, a commonly used edible plant in dietary consumption, has attracted significant attention due to its management of diabetes and its associated complications. The research presented in this study examines the potential therapeutic benefits of fenugreek in treating ED and investigates the underlying mechanism associated with its effects. The analysis on fenugreek was performed using 70% ethanol extract, and its chemical composition was analyzed using ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS). In total, we identified 49 compounds present in the fenugreek extract. These compounds encompass flavonoids, saponins, and phospholipids. Then, the models of ED in streptozotocin-induced diabetic mice and high glucose-induced isolated rat aortas were established for research. Through vascular function testing, it was observed that fenugreek extract effectively improved ED induced by diabetes or high glucose. By analyzing the protein expression of arginase 1 (Arg1), Arg activity, Arg1 immunohistochemistry, nitric oxide (NO) level, and the protein expression of endothelial nitric oxide synthase (eNOS), p38 mitogen-activated protein kinase (p38 MAPK), and p-p38 MAPK in aortas, this study revealed that the potential mechanism of fenugreek extract in anti-ED involves the downregulation of Arg1, leading to enhanced NO production. Furthermore, analysis of serum exosomes carrying Arg activity indicates that fenugreek may decrease the activity of Arg transported by serum exosomes, potentially preventing the increase in Arg levels triggered by the uptake of serum exosomes by vascular endothelial cells. In general, this investigation offers valuable observations regarding the curative impact of fenugreek extract on anti-ED in diabetes, revealing the involvement of the Arg1 pathway in its mechanism.

Identification of the absorbed constituents and metabolites of Huangqi Guizhi Wuwu decoction by ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry

Huangqi Guizhi Wuwu decoction (HGWWD) is a widely used traditional Chinese medicine (TCM) preparation for the treatment of ischemic stroke and diabetes peripheral neuropathy. However, the material basis for the efficacy of HGWWD remains unclear. In this study, a rapid, sensitive and selective ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) method was developed to separate and identify the absorbed components and metabolites of HGWWD in rat plasma after oral administration for the first time. By comparing the retention time, high-resolution mass spectrometry primary and secondary mass spectrometry data of blank plasma and drug-containing plasma, a total of 42 constituents, including 24 prototype compounds and 18 metabolites, were identified or tentatively characterized. The results indicated that monoterpenes, flavonoids, organic acids, amino acids, gingerols and alkaloids were main prototype compounds in rat plasma, and flavonoid-related metabolites, organic acid-related metabolites and gingerol-related metabolites were major metabolites. It is concluded the developed UHPLC-Q-TOF-MS method with high sensitivity and resolution is suitable for identifying and characterizing the absorbed components and metabolites of HGWWD, and the results will provide important data for further study on the relationship between the chemical constituents and pharmacological activities of HGWWD.

Zinc-Dependent Histone Deacetylases in Lung Endothelial Pathobiology

A monolayer of endothelial cells (ECs) lines the lumen of blood vessels and, as such, provides a semi-selective barrier between the blood and the interstitial space. Compromise of the lung EC barrier due to inflammatory or toxic events may result in pulmonary edema, which is a cardinal feature of acute lung injury (ALI) and its more severe form, acute respiratory distress syndrome (ARDS). The EC functions are controlled, at least in part, via epigenetic mechanisms mediated by histone deacetylases (HDACs). Zinc-dependent HDACs represent the largest group of HDACs and are activated by Zn2+. Members of this HDAC group are involved in epigenetic regulation primarily by modifying the structure of chromatin upon removal of acetyl groups from histones. In addition, they can deacetylate many non-histone histone proteins, including those located in extranuclear compartments. Recently, the therapeutic potential of inhibiting zinc-dependent HDACs for EC barrier preservation has gained momentum. However, the role of specific HDAC subtypes in EC barrier regulation remains largely unknown. This review aims to provide an update on the role of zinc-dependent HDACs in endothelial dysfunction and its related diseases. We will broadly focus on biological contributions, signaling pathways and transcriptional roles of HDACs in endothelial pathobiology associated mainly with lung diseases, and we will discuss the potential of their inhibitors for lung injury prevention.

Serum histone deacetylase 4 longitudinal change for estimating major adverse cardiovascular events in acute coronary syndrome patients receiving percutaneous coronary intervention

OBJECTIVE

Histone deacetylase 4 (HDAC4) regulates lipid accumulation, inflammation, endothelial injury, and atherosclerosis to participate in the pathogenesis of cardiovascular diseases. This study aimed to explore the value of serum HDAC4 change before and after percutaneous coronary intervention (PCI) in predicting major adverse cardiovascular events (MACE) risk in acute coronary syndrome (ACS) patients.

METHODS

HDAC4 from serum was detected by enzyme-linked immunosorbent assay in 340 ACS patients at baseline, day (D)1, D3, and D7 after PCI, and from 30 healthy controls (HCs). MACE was recorded during follow-up.

RESULTS

HDAC4 was decreased in ACS patients versus HCs (P < 0.001). In ACS patients, HDAC4 was negatively related to total cholesterol (P = 0.025), low-density lipoprotein cholesterol (P = 0.007), C-reactive protein (P < 0.001), cardiac troponin I (P < 0.001), and hyperlipidemia history (P = 0.015). Additionally, HDAC4 was lowest in ST-elevation myocardial infarction (STEMI) patients, followed by non-STEMI patients, and highest in unstable angina patients (P = 0.010). After PCI, HDAC4 was decreased from baseline to D1, then increased until D7 (P < 0.001). Furthermore, HDAC4 at baseline (P = 0.002), D1 (P < 0.001), D3 (P < 0.001), and D7 (P < 0.001) were all reduced in patients who experienced MACE versus those who did not. Meanwhile, high HDAC4 at baseline (P = 0.036), D1 (P = 0.010), D3 (P = 0.012), and D7 (P = 0.012) estimated decreased accumulating MACE risk by Kaplan-Meier curve. Multivariate logistic analysis revealed that HDAC4 at D1 was independently linked to lower MACE risk (odds ratio = 0.957, P = 0.039).

CONCLUSION

Serum HDAC4 is decreased from baseline to D1, then elevated until D7, and its increased level correlates with lower MACE risk in ACS patients receiving PCI.

Characterization of chemical constituents in Huangqi Guizhi Wuwu decoction using ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry

Huangqi Guizhi Wuwu decoction (HGWWD) is a classic traditional Chinese medicine prescription for the treatment of ischemic stroke, etc. However, the material basis of its efficacy remains unclear, seriously affecting drug development and clinical applications. In the present study, an ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry method was developed to separate and identify the chemical components of HGWWD. A total of 81 compounds were identified and tentatively characterized. Eight compounds were accurately identified by comparing the retention time and mass spectrometry data with those of reference substances, the remaining compounds were characterized by comparing the mass spectrometry data and reference information. Based on the results of compound attribution, 35 compounds were from Astragali Radix, six compounds were from Cinnamomi Ramulus, 23 compounds were from Paeoniae Radix Alba, eight compounds were from Zingiberis Rhizoma Recens and nine compounds were from Jujubae Fructus. The results showed that monoterpenoids, flavonoids, organic acids, triterpenes, amino acids, gingerols, alkaloids, and glycosides were the main chemical components of HGWWD. This analytical method is suitable for characterizing the chemical constituents of HGWWD, and the results provide important information for elucidating its pharmacodynamic material basis and mechanism of action.