Puerarin pretreatment attenuates cardiomyocyte apoptosis induced by coronary microembolization in rats by activating the PI3K/Akt/GSK-3β signaling pathway

Research Progress of Regulatory Cell Death in Coronary Microembolization

Coronary microembolization (CME) is defined as atherosclerotic plaque erosion, spontaneous rupture, or rupture of the plaque while undergoing interventional therapy resulting in the formation of tiny emboli that obstruct the coronary microcirculatory system. For percutaneous coronary intervention, CME is a major complication, with a periprocedural incidence of up to 25%. Recent studies have demonstrated that regulatory cell death (RCD) exerts a profound influence on CME through its modulation of inflammatory responses, oxidative stress, cell death, and angiogenesis. RCD, including apoptosis, autophagy, and pyroptosis, is a unique class of genetically highly regulated death patterns pervasive in instances of coronary microembolization. The aim of this review is to summarize the currently known molecular mechanisms underlying CME. Further investigations of the RCD mechanisms may unravel new avenues for the prevention and treatment of CME.

The beneficial health effects of puerarin in the treatment of cardiovascular diseases: from mechanisms to therapeutics

Cardiovascular diseases (CVDs) are the leading causes of death globally that seriously threaten human health. Although novel western medicines have continued to be discovered over the past few decades to inhibit the progression of CVDs, new drug research and development for treating CVDs with less side effects and adverse reactions are continuously being desired. Puerarin is a natural product found in a variety of medicinal plants belonging to the flavonoid family with potent biological and pharmacological activities. Abundant research findings in the literature have suggested that puerarin possesses a promising prospect in treating CVDs. In recent years, numerous new molecular mechanisms of puerarin have been explored in experimental and clinical studies, providing new evidence for this plant metabolite to protect against CVDs. This article systematically introduces the history of use, bioavailability, and various dosage forms of puerarin and further summarizes recently published data on the major research advances and their underlying therapeutic mechanisms in treating CVDs. It may provide references for researchers in the fields of pharmacology, natural products, and internal medicine.

Puerarin Suppresses Glycolysis and Increases Cisplatin Chemosensitivity in Oral Squamous Cell Carcinoma via FBXW7/mTOR Signaling

This study aimed to observe the effects of puerarin on glycolysis and cisplatin sensitivity in oral squamous cell carcinoma (oSCC) cells and to explore the underlying mechanisms. CAL27 cells over- or under-expressing FBXW7 were treated with cisplatin or puerarin, and the levels of proteins involved in glycolysis as well as the activity of the respective enzymes were assessed. Glucose uptake and lactate production were also evaluated, and the IC50 value of cisplatin in CAL27 cells was determined. FBXW7 overexpression significantly downregulated HK2, PKM2, and LDH; suppressed the activity of the corresponding enzymes hexokinase, pyruvate kinase, and lactate dehydrogenase; as well as reduced glucose uptake and lactate production. FBXW7 overexpression was also associated with decreased mTOR phosphorylation and increased cisplatin sensitivity. These effects were partially antagonized by lactate or the mTOR agonist MHY1485. Puerarin suppressed glycolysis by reducing glucose uptake and lactate production, while it promoted cisplatin sensitivity and activated the FBXW7/mTOR signal pathway in a concentration-dependent manner. These effects were antagonized by FBXW7 downregulation or treatment with MHY1485. Our results suggest that FBXW7 improves cisplatin chemosensitivity and suppresses glycolysis in oSCC cells, indicating its promising potential as a target for puerarin to regulate the cisplatin sensitivity of oSCC cells.

The Importance of Integrated Regulation Mechanism of Coronary Microvascular Function for Maintaining the Stability of Coronary Microcirculation: An Easily Overlooked Perspective

Coronary microvascular dysfunction (CMD) refers to a group of disorders affecting the structure and function of coronary microcirculation and is associated with an increased risk of major adverse cardiovascular events. At present, great progress has been made in the diagnosis of CMD, but there is no specific treatment for it because of the complexity of CMD pathogenesis. Vascular dysfunction is one of the important causes of CMD, but previous reviews mostly considered microvascular dysfunction as a whole abnormality so the obtained conclusions are skewed. The coronary microvascular function is co-regulated by multiple mechanisms, and the mechanisms by which microvessels of different luminal diameters are regulated vary. The main purpose of this review is to revisit the mechanisms by which coronary microvessels at different diameters regulate coronary microcirculation through integrated sequential activation and briefly discuss the pathogenesis, diagnosis, and treatment progress of CMD from this perspective.

Virtual screening analysis of natural flavonoids as trimethylamine (TMA)-lyase inhibitors for coronary heart disease

Coronary heart disease (CHD) is defined by atherosclerosis, which can result in stenosis or blockage of the arterial cavity, leading to ischemic cardiac diseases such as angina and myocardial infarction. Accumulating evidence indicates that the gut microbiota plays a vital role in the beginning and progression of CHD. The gut microbial metabolite, trimethylamine-N-oxide (TMAO), is intimately linked to the pathophysiology of CHD. TMAO is formed when trimethylamine (TMA) is converted by flavin-containing monooxygenases in the hepatocytes. Therefore, inhibition of TMA production is essential to reduce TMAO levels. Flavonoids may reduce the risk of death from cardiovascular disease. In this article, we reviewed and evaluated twenty-two flavonoids for the therapy of CHD based on their inhibition of TMA-lyase by molecular docking. Docking results revealed that baicalein, fisetin, acacetin, and myricetin in flavonoid aglycones, and baicalin, naringin, and hesperidin in flavonoid glycosides had a good binding effect with TMA-lyase. This indicates that these chemicals were the most active and could be used as lead compounds for structural modification in the future. PRACTICAL APPLICATIONS: Flavonoids are a large class of polyphenolic compounds found in fruits, vegetables, flowers, tea, and herbal medicines, which are inexorably metabolized and transformed into bioactive metabolites by α-rhamnosidase, β-glucuronidase, β-glucosidase, and nitroreductase produced by the gut microbiota, which plays a beneficial role in the prevention and treatment of cardiovascular diseases. Because flavonoids protect the cardiovascular system and regulate the gut microbiota, and the gut microbiota is directly connected to TMAO, thus, reducing TMAO levels involves blocking the transition of TMA to TMAO, which may be performed by reducing TMA synthesis. Molecular docking results found that baicalein, fisetin, acacetin, and myricetin in flavonoid aglycones, and baicalin, naringin, and hesperidin in flavonoid glycosides had good binding effects on TMA-lyase, which were the most active and could be used as lead compounds for structural modification.

Pharmacological Activity, Pharmacokinetics, and Clinical Research Progress of Puerarin

As a kind of medicine and food homologous plant, kudzu root (Pueraria lobata (Willd.) Ohwi) is called an "official medicine" in Chinese folk medicine. Puerarin is the main active component extracted from kudzu root, and its structural formula is 8-β-D-grapes pyranose-4, 7-dihydroxy isoflavone, with a white needle crystal; it is slightly soluble in water, and its aqueous solution is colorless or light yellow. Puerarin is a natural antioxidant with high health value and has a series of biological activities such as antioxidation, anti-inflammation, anti-tumor effects, immunity improvement, and cardio-cerebrovascular and nerve cell protection. In particular, for the past few years, it has also been extensively used in clinical study. This review focuses on the antioxidant activity of puerarin, the therapy of diverse types of inflammatory diseases, various new drug delivery systems of puerarin, the "structure-activity relationship" of puerarin and its derivatives, and pharmacokinetic and clinical studies, which can provide a new perspective for the puerarin-related drug research and development, clinical application, and further development and utilization.

A fresh look at coronary microembolization

Mechanical stress from haemodynamic perturbations or interventional manipulation of epicardial coronary atherosclerotic plaques with inflammatory destabilization can release particulate debris, thrombotic material and soluble substances into the coronary circulation. The physical material obstructs the coronary microcirculation, whereas the soluble substances induce endothelial dysfunction and facilitate vasoconstriction. Coronary microvascular obstruction and dysfunction result in patchy microinfarcts accompanied by an inflammatory reaction, both of which contribute to progressive myocardial contractile dysfunction. In clinical studies, the benefit of protection devices to retrieve atherothrombotic debris during percutaneous coronary interventions has been modest, and the treatment of microembolization has mostly relied on antiplatelet and vasodilator agents. The past 25 years have witnessed a relative proportional increase in non-ST-segment elevation myocardial infarction in the presentation of acute coronary syndromes. An associated increase in the incidence of plaque erosion rather than rupture has also been recognized as a key mechanism in the past decade. We propose that coronary microembolization is a decisive link between plaque erosion at the culprit lesion and the manifestation of non-ST-segment elevation myocardial infarction. In this Review, we characterize the features and mechanisms of coronary microembolization and discuss the clinical trials of drugs and devices for prevention and treatment.

Resveratrol Pretreatment Inhibits Myocardial Apoptosis in Rats Following Coronary Microembolization via Inducing the PI3K/Akt/GSK-3β Signaling Cascade

Purpose

Coronary microembolization (CME) is associated with progressive cardiac dysfunction, myocardial inflammation, and apoptosis. Resveratrol (RES) has a considerable role in cardioprotection. However, the contribution and possible mechanisms of RES in CME have not been clearly understood.

Methods

In the current study, 40 SD rats were randomly selected and categorized into various groups including CME, CME + resveratrol (CME + RES), CME + resveratrol+ LY294002 (CME + RES + LY), and sham groups (10 animals in each group). The inert plastic microspheres (42 μm) were injected into the rats’ left ventricle for developing the CME model. Then resveratrol (25 mg/kg/d) was given to the rats in the CME + RES and CME + RES + LY groups for one week before CME induction. Furthermore, LY294002 (10 mg/kg) was intraperitoneally injected into the rats of the CME + RES + LY group 0.5 hours before CME modeling. The cardiac functions, serum levels of myocardial injury biomarkers, myocardial histopathology, and mRNA and proteins associated with myocardial apoptosis were all assessed 12 hours after surgery.

Results

The results revealed that resveratrol pretreatment alleviated the CME-induced myocardial damage by improving cardiac dysfunction, and lowering the serum level of myocardial injury biomarkers, myocardial microinfarct size, and cardiomyocyte apoptotic index. Pretreatment with resveratrol reduced the level of proteins and mRNAs associated with the pro-apoptosis in myocardial tissues and increased the levels of proteins and mRNAs associated with the anti-apoptosis. Moreover, the combined treatment of resveratrol and LY294002 reversed the observed protective effects.

Conclusion

Resveratrol can inhibit cardiomyocyte apoptosis, thus attenuating the CME-induced myocardial injury by triggering the PI3K/Akt/GSK-3β cascade.