Total flavonoids from Ganshanbian (Herba Hyperici Attenuati) effect the expression of CaL-α1C and KATP-Kir6.1 mRNA of the myocardial cell membrane in myocardial ischemia-reperfusion arrhythmia rats

DJ-1: Potential target for treatment of myocardial ischemia-reperfusion injury

Ischemic heart disease (IHD) is a significant global health concern, resulting in high rates of mortality and disability among patients. Although coronary blood flow reperfusion is a key treatment for IHD, it often leads to acute myocardial ischemia-reperfusion injury (IRI). Current intervention strategies have limitations in providing adequate protection for the ischemic myocardium. DJ-1, originally known as a Parkinson's disease related protein, is a highly conserved cytoprotective protein. It is involved in enhancing mitochondrial function, scavenging reactive oxygen species (ROS), regulating autophagy, inhibiting apoptosis, modulating anaerobic metabolism, and exerting anti-inflammatory effects. DJ-1 is also required for protective strategies, such as ischemic preconditioning, ischemic postconditioning, remote ischemic preconditioning and pharmacological conditioning. Therefore, DJ-1 emerges as a potential target for the treatment of myocardial IRI. Our comprehensive review delves into its protective mechanisms in myocardial IRI and the structural foundations underlying its functions.

Effects of Hypericum attenuatum Choisy extract on the immunologic function and intestinal microflora of broilers under oxidative stress

This study investigated the impact of Hypericum attenuatum Choisy extract (HYG) on immunological function and the cecum microflora in broilers. A total of 240 one-day-old AA broilers were randomly divided into 5 groups with 6 replicates of 8 broilers each: 1) the CN group, in which broilers were injected with saline and fed a basal diet; 2) the PC group, in which broilers were injected with lipolyaccharide (LPS) and fed a basal diet; 3) the HYG1 group, in which broilers were injected with LPS and fed a 400 mg/kg HYG-supplemented diet; 4) the HYG2 group, in which broilers were injected with LPS and fed a 800 mg/kg HYG-supplemented diet; 5) the HYG3 group, in which broilers were injected with LPS and fed a 1,200 mg/kg HYG-supplemented diet. Broilers were injected with 1 mg/kg LPS or the same amount saline 12 hours before sampling on d 21 and 42. The results revealed that dietary 400 mg/kg HYG supplementation alleviated spleen index and thymus index abnormalities, balanced the disturbance of serum immunoglobulin (Ig)M and IgA levels, and regulated the cytokine balance in the serum, liver, spleen and jejunum tissues included induced by LPS. Dietary supplementation with 400 mg/kg HYG also downregulated the relative expression of the inhibitor of kappa B kinase alpha (IKKα) and interleukin (IL)-6 mRNAs in the liver and upregulated the relative expression of the inhibitor kappa B alpha (IκBα) and IL-10 mRNAs in the spleen. Dietary HYG improved the cecal microflora balance at 42 d by increasing the relative abundance of beneficial bacteria, such as Alistipes and Phascolarctobacterium, while reducing the relative abundance of harmful bacteria, such as Helicobacter and Colidextribacter. Spearman correlation analysis revealed a negative correlation between activation of the NF-κB inhibitory pathway in the liver and the presence of Phascolarctobacterium, Erysipelatoclostridium, Subdoligranulum and Parabacteroides. Conclusions: The incorporation of 400 mg/kg HYG into the diet was optimal in improving broiler immunological function.

Chinese herbal medicine for the treatment of cardiovascular diseases ─ targeting cardiac ion channels

Cardiovascular disease (CVD) remains the leading cause of morbidity and mortality, imposing an increasing global health burden. Cardiac ion channels (voltage-gated Na_V, Ca_V, K_Vs, and others) synergistically shape the cardiac action potential (AP) and control the heartbeat. Dysfunction of these channels, due to genetic mutations, transcriptional or post-translational modifications, may disturb the AP and lead to arrhythmia, a major risk for CVD patients. Although there are five classes of anti-arrhythmic drugs available, they can have varying levels of efficacies and side effects on patients, possibly due to the complex pathogenesis of arrhythmias. As an alternative treatment option, Chinese herbal remedies have shown promise in regulating cardiac ion channels and providing anti-arrhythmic effects. In this review, we first discuss the role of cardiac ion channels in maintaining normal heart function and the pathogenesis of CVD, then summarize the classification of Chinese herbal compounds, and elaborate detailed mechanisms of their efficacy in regulating cardiac ion channels and in alleviating arrhythmia and CVD. We also address current limitations and opportunities for developing new anti-CVD drugs based on Chinese herbal medicines.

Effects of plant growth regulators on the contents of rutin, hyperoside and quercetin in Hypericum attenuatum Choisy

To explore the accumulation of rutin, hyperoside and quercetin in Hypericum attenuatum Choisy under treatment with different plant growth regulators, 100 mg/L, 200 mg/L and 300 mg/L cycocel, 100 mg/L, 200 mg/L and 300 mg/L mepiquat chloride and 1 mg/L, 2 mg/L and 3 mg/L naphthalene acetic acid were foliage sprayed on Hypericum attenuatum Choisy plants at the early growth stage. We sampled and determined the important flavonoid contents at the flowering stage. The results showed that the three plant growth regulators had different effects on the accumulation of rutin, hyperoside and quercetin in the leaves, stems and flowers of Hypericum attenuatum Choisy at the flowering stage. After spraying 1 mg/L naphthalene acetic acid at the early growth stage, the rutin contents in the leaves, stems and flowers increased by approximately 60.33%, 223.85% and 192.02%, respectively (P < 0.05). Spraying 100 mg/L mepiquat chloride increased the hyperoside contents in the leaves and flowers by approximately 7.77% and 12.87%, respectively (P < 0.05). Spraying 2 mg/L naphthalene acetic acid significantly increased the quercetin contents in the flowers and leaves by approximately 95.62% and 47.85%, respectively (P < 0.05). Therefore, at the early growth stage, spraying 1 mg/L naphthalene acetic acid significantly increased rutin content, spraying 100 mg/L mepiquat chloride significantly increased hyperoside content, and spraying 2 mg/L naphthalene acetic acid significantly increased quercetin content in Hypericum attenuatum Choisy. In conclusion, the accumulation of flavonoids in Hypericum attenuatum Choisy was regulated by plant growth regulators.

Mechanism-based targeting of cardiac arrhythmias by phytochemicals and medicinal herbs: A comprehensive review of preclinical and clinical evidence

Cardiac arrhythmias, characterized by an irregular heartbeat, are associated with high mortality and morbidity. Because of the narrow therapeutic window of antiarrhythmic drugs (AADs), the management of arrhythmia is still challenging. Therefore, searching for new safe, and effective therapeutic options is unavoidable. In this study, the antiarrhythmic effects of medicinal plants and their active constituents were systematically reviewed to introduce some possible candidates for mechanism-based targeting of cardiac arrhythmias. PubMed, Embase, and Cochrane library were searched from inception to June 2021 to find the plant extracts, phytochemicals, and multi-component herbal preparations with antiarrhythmic activities. From 7337 identified results, 57 original studies consisting of 49 preclinical and eight clinical studies were finally included. Three plant extracts, eight multi-component herbal preparations, and 26 phytochemicals were found to have antiarrhythmic effects mostly mediated by affecting K+ channels, followed by modulating Ca2+ channels, upstream target pathways, Nav channels, gap junction channels, and autonomic receptors. The most investigated medicinal plants were Rhodiola crenulata and Vitis vinifera. Resveratrol, Oxymatrine, and Curcumin were the most studied phytochemicals found to have multiple mechanisms of antiarrhythmic action. This review emphasized the importance of research on the cardioprotective effect of medicinal plants and their bioactive compounds to guide the future development of new AADs. The most prevalent limitation of the studies was their unqualified methodology. Thus, future well-designed experimental and clinical studies are necessary to provide more reliable evidence.

Flavonoids in myocardial ischemia-reperfusion injury: Therapeutic effects and mechanisms

Ischemic heart diseases are one of the major causes of death worldwide. Effective restoration of blood flow can significantly improve patients' quality of life and reduce mortality. However, reperfusion injury cannot be ignored. Flavonoids possess well-established antioxidant properties; They also have other benefits that may be relevant for ameliorating myocardial ischemia-reperfusion injury (MIRI). In this review, we focus on flavonoids with cardiovascular-protection function and emphasize their pharmacological effects. The main mechanisms of flavonoid pharmacological activities against MIRI involve the following aspects: a) antioxidant, b) anti-inflammatory, c) anti-platelet aggregation, d) anti-apoptosis, and e) myocardial-function regulation activities. We also summarized the effectiveness of flavonoids for MIRI.

Herbal Medicines for Diabetes Management and its Secondary Complications

Diabetic Mellitus (DM) is a metabolic disorder that is concerning for people all over the world. DM is caused due to lack of insulin or ineffective production of insulin in the pancreas. A total of 463 million people were reported to have diabetes mellitus in 2019 and this number is predicted to rise up to 578 million by the year 2030 and 700 million by 2045. High blood sugar gives rise to many complications like diabetic retinopathy, diabetic nephropathy, atherosclerosis, hypercoagulability, cardiovascular disease, coronary heart disease, abdominal obesity, hypertension, hyperlipidemia, cerebrovascular disease, coronary artery disease, foot damage, skin complications, Alzheimer's disease, hearing impairment, and depression. These life-threatening complications make diabetes more severe than other diseases. Many synthetic drugs have been developed, but still, a complete cure is not provided by any of the molecules. Continuous use of some synthetic agents causes severe side effects, and thus the demand for non-toxic, affordable drugs still persists. Traditional treatments have been an extremely valued source of medicine all over human history. These are extensively used throughout the world, indicating that herbs are a growing part of modern and high-tech medicines. The World Health Organization (WHO) has listed a total of 21,000 plants, which are used for medicinal purposes around the world. Among them, more than 400 plants are available for the treatment of diabetes. Despite the fact that there are many herbal drugs available for treating diabetes, only a small number of these plants have undergone scientific and medical evaluation to assess their efficacy. Trigonella foenum-graecum, Allium sativum, Caesalpinia bonduc, Ferula assafoetida,etc., are some of the medicinal plants used for antidiabetic therapy. The presence of phenolic compounds, flavonoids, terpenoids, and coumarins is responsible for the antidiabetic nature of the medicinal plants. These constituents have shown a reduction in blood glucose levels. Pycnogenol, acarbose, miglitol, and voglibose are some of the examples of marketed drugs, which are obtained from natural origin and used as antidiabetic drugs. The active principles derived from the plants work through many antidiabetic mechanisms, which include inhibition of α-glucosidase, α-amylase, and protein tyrosine phosphatase 1B activities. One of the major advantages of herbal drugs is the low level of side effects attributed to these medicines, and this attracted various researchers to develop new molecules for the treatment of diabetes. In this review, recent advances in the field of herbal drugs to treat diabetes, prevent secondary complications from arising due to diabetes, and various herbal molecules in different stages of clinical trials will be emphasized upon.

ArrhythmoGenoPharmacoTherapy

This review is focusing on the understanding of various factors and components governing and controlling the occurrence of ventricular arrhythmias including (i) the role of various ion channel-related changes in the action potential (AP), (ii) electrocardiograms (ECGs), (iii) some important arrhythmogenic mediators of reperfusion, and pharmacological approaches to their attenuation. The transmembrane potential in myocardial cells is depending on the cellular concentrations of several ions including sodium, calcium, and potassium on both sides of the cell membrane and active or inactive stages of ion channels. The movements of Na+, K+, and Ca2+ via cell membranes produce various currents that provoke AP, determining the cardiac cycle and heart function. A specific channel has its own type of gate, and it is opening and closing under specific transmembrane voltage, ionic, or metabolic conditions. APs of sinoatrial (SA) node, atrioventricular (AV) node, and Purkinje cells determine the pacemaker activity (depolarization phase 4) of the heart, leading to the surface manifestation, registration, and evaluation of ECG waves in both animal models and humans. AP and ECG changes are key factors in arrhythmogenesis, and the analysis of these changes serve for the clarification of the mechanisms of antiarrhythmic drugs. The classification of antiarrhythmic drugs may be based on their electrophysiological properties emphasizing the connection between basic electrophysiological activities and antiarrhythmic properties. The review also summarizes some important mechanisms of ventricular arrhythmias in the ischemic/reperfused myocardium and permits an assessment of antiarrhythmic potential of drugs used for pharmacotherapy under experimental and clinical conditions.

From in silico to in vitro: a trip to reveal flavonoid binding on the Rattus norvegicus Kir6.1 ATP-sensitive inward rectifier potassium channel

Background

ATP-sensitive inward rectifier potassium channels (Kir), are a potassium channel family involved in many physiological processes. K_ATP dysfunctions are observed in several diseases such as hypoglycaemia, hyperinsulinemia, Prinzmetal angina–like symptoms, cardiovascular diseases.

Methods

A broader view of the K_ATP mechanism is needed in order to operate on their regulation, and in this work we clarify the structure of the Rattus norvegicus ATP-sensitive inward rectifier potassium channel 8 (Kir6.1), which has been obtained through a homology modelling procedure. Due to the medical use of flavonoids, a considerable increase in studies on their influence on human health has recently been observed, therefore our aim is to study, through computational methods, the three-dimensional (3D) conformation together with mechanism of action of Kir6.1 with three flavonoids.

Results

Computational analysis by performing molecular dynamics (MD) and docking simulation on rat 3D modelled structure have been completed, in its closed and open conformation state and in complex with Quercetin, 5-Hydroxyflavone and Rutin flavonoids. Our study showed that only Quercetin and 5-Hydroxyflavone were responsible for a significant down-regulation of the Kir6.1 activity, stabilising it in a closed conformation. This hypothesis was supported by in vitro experiments demonstrating that Quercetin and 5-Hydroxyflavone were capable to inhibit K_ATP currents of rat tail main artery myocytes recorded by the patch-clamp technique.

Conclusion

Combined methodological approaches, such as molecular modelling, docking and MD simulations of Kir6.1 channel, used to elucidate flavonoids intrinsic mechanism of action, are introduced, revealing a new potential druggable protein site.

Nitric Oxide Regulates The Lymphatic Reactivity Following Hemorrhagic Shock Through Atp-Sensitive Potassium Channel

Lymphatic reactivity has been shown to exhibit a biphasic change following hemorrhagic shock, and nitric oxide (NO) is involved in this process. However, the precise mechanism responsible for NO regulation of the lymphatic reactivity along with the progression of hemorrhagic shock is unclear. Therefore, the present study was to investigate how NO participates in regulating the shock-induced biphasic changes in lymphatic reactivity and its underlying mechanisms. First, the expressions or contents of inducible NO synthase, nitrite plus nitrate, and elements of cAMP-PKA-KATP and cGMP-PKG-KATP pathway in thoracic ducts tissue were assessed. The results revealed that levels of nitrite plus nitrate, cAMP, cyclic guanosine monophosphate (cGMP), p-PKA, and p-PKG were increased gradually along with the process of shock. Second, the roles of cAMP-PKA-KATP and cGMP-PKG-KATP in NO regulating lymphatic response to gradient substance P were evaluated with an isolated lymphatic perfusion system. The results showed that the NOS substrate (L-Arg), PKA donor (8-Br-cAMP) decreased the reactivity of shock 0.5 h-lymphatics, and that the PKA inhibitor (H-89) and KATP inhibitor (glibenclamide) restrained the effects of L-Arg while glibenclamide abolished the effects of 8-Br-cAMP. Meanwhile, NOS antagonist (L-NAME), protein kinase G (PKG) inhibitor (KT-5823), and soluble guanylate cyclase inhibitor (ODQ) increased the reactivity of shock 2 h-lymphatics, whereas KATP opener (pinacidil) inhibited these elevated effects induced by either L-NAME, ODQ, or KT-5823. Taken together, these results indicate that NO regulation of lymphatic reactivity during shock involves both cAMP-PKA-KATP and cGMP-PKG-KATP pathways. These findings have potential significance for the treatment of hemorrhagic shock through regulating lymphatic reactivity.

The Role of Biologically Active Ingredients from Natural Drug Treatments for Arrhythmias in Different Mechanisms

Arrhythmia is a disease that is caused by abnormal electrical activity in the heart rate or rhythm. It is the major cause of cardiovascular morbidity and mortality. Although several antiarrhythmic drugs have been used in clinic for decades, their application is often limited by their adverse effects. As a result, natural drugs, which have fewer side effects, are now being used to treat arrhythmias. We searched for all articles on the role of biologically active ingredients from natural drug treatments for arrhythmias in different mechanisms in PubMed. This study reviews 19 natural drug therapies, with 18 active ingredient therapies, such as alkaloids, flavonoids, saponins, quinones, and terpenes, and two kinds of traditional Chinese medicine compound (Wenxin-Keli and Shensongyangxin), all of which have been studied and reported as having antiarrhythmic effects. The primary focus is the proposed antiarrhythmic mechanism of each natural drug agent. Conclusion. We stress persistent vigilance on the part of the provider in discussing the use of natural drug agents to provide a solid theoretical foundation for further research on antiarrhythmia drugs.

Cardioprotective Effects of Astragalin against Myocardial Ischemia/Reperfusion Injury in Isolated Rat Heart

This study aims to evaluate the cardioprotective effects of astragalin against myocardial ischemia/reperfusion (I/R) injury in isolated rat heart. The cardioprotective effects of astragalin on myocardial I/R injury were investigated on Langendorff apparatus. Adult male Sprague-Dawley rats were randomly divided into five groups. The results showed that astragalin pretreatment improved myocardial function. Compared with I/R group, lactate dehydrogenase (LDH) and creatine kinase (CK) activities in coronary flow decreased in astragalin pretreatment groups, whereas superoxide dismutase (SOD) activity and glutathione/glutathione disulfide (GSH/GSSG) ratio significantly increased. The levels of malondialdehyde (MDA), intracellular reactive oxygen species (ROS), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) decreased in astragalin-treated groups. The infarct size (IS) and apoptosis rate in hearts from astragalin-treated groups were lower than those in hearts from the I/R group. Western blot analysis also revealed that astragalin preconditioning significantly reduced Bax level, whereas Bcl-2 was increased in the myocardium. Therefore, astragalin exhibited cardioprotective effects via its antioxidative, antiapoptotic, and anti-inflammatory activities.