Baicalin attenuates myocardial ischemia-reperfusion injury through Akt/NF-κB pathway

PI3K/AKT pathway: A potential therapeutic target in cerebral ischemia-reperfusion injury

Cerebral ischemia is a prevalent cerebrovascular disorder, with the restoration of blocked blood vessels serving as the current standard clinical treatment. However, reperfusion can exacerbate neuronal damage and neurological dysfunction, resulting in cerebral ischemia-reperfusion (I/R) injury. Presently, clinical treatment strategies for cerebral I/R injury are limited, creating an urgent need to identify new effective therapeutic targets. The PI3K/AKT signaling pathway, a pro-survival pathway associated with cerebral I/R injury, has garnered significant attention. We conducted a comprehensive review of the literature on the PI3K/AKT pathway in the context of cerebral I/R. Our findings indicate that activation of the PI3K/AKT signaling pathway following cerebral I/R can alleviate oxidative stress, reduce endoplasmic reticulum stress (ERS), inhibit inflammatory responses, decrease neuronal apoptosis, autophagy, and pyroptosis, mitigate blood-brain barrier (BBB) damage, and promote neurological function recovery. Consequently, this pathway ultimately reduces neuronal death, alleviates brain tissue damage, decreases the volume of cerebral infarction, and improves behavioral impairments. These results suggest that the PI3K/AKT signaling pathway is a promising therapeutic target for further research and drug development, holding significant potential for the treatment of cerebral I/R injury.

Baicalin reduces sunitinib-induced cardiotoxicity in renal carcinoma PDX model by inhibiting myocardial injury, apoptosis and fibrosis

Sunitinib (SU), a multi-targeted tyrosine kinase inhibitor, has anticancer function but its clinical use is often limited by cardiovascular complications. Baicalin (BA) has demonstrated various pharmacological activities including antioxidant, anti-inflammatory and antiviral properties, but its potential roles in SU-induced cardiotoxicity have not been reported. In this study, we aimed to investigate the effect of BA in SU-induced cardiotoxicity in vivo by using renal carcinoma patient-derived xenograft (PDX) model. Female Nod Scid mice with renal carcinoma PDX were treated with vehicle, SU (50 mg/kg/d), BA (100 mg/kg/d), or BA combined with SU for 6 weeks. The tumor volume and weight of tumor-bearing mice were measured, and cardiovascular functions were evaluated by testing the Heart index and blood biochemical indicators, and by hematoxylin and eosin (H&E), Masson and Tunel staining. The results showed that SU therapy and combination therapy effectively inhibited the growth of renal tumors. Combination therapy inhibited SU-induced increase of creatine kinase (CK) and lactate dehydrogenase (LDH), and ameliorated the heart parameters. Moreover, BA effectively protected SU-induced cardiac dysfunction by decreasing injury, apoptosis, and fibrosis. Collectively, our results demonstrate that BA can be as a potential cardioprotective approach for cardiovascular complications during SU regimen.

Baicalin and baicalein against myocardial ischemia-reperfusion injury: A review of the current documents

Myocardial ischemia-reperfusion injury (MIRI) is a significant challenge in the treatment of ischemic heart disease (IHD), arising as a complication from reperfusion therapies designed to restore blood flow after an ischemic event. Despite the availability of various therapeutic strategies, finding an effective treatment for MIRI remains difficult. Baicalin and its aglycone form (baicalein), natural compounds derived from the Chinese skullcap plant (Scutellaria baicalensis), have shown promise due to their antioxidant, anti-inflammatory, and cardioprotective properties. This review aims to explore the potential of baicalin and baicalein as treatments for MIRI, with a focus on their molecular and cellular level effects. These natural agents can decrease oxidative stress by promoting antioxidant enzymes and decreasing harmful oxidative substances that damage cardiac cells. They also exert anti-inflammatory effects by blocking specific pathways that trigger the release of inflammatory mediators. Additionally, they also improve heart cell survival, infarct region, and overall cardiac function by inhibiting key signaling pathways involved in cell death. Research in both animal and cell models suggests that these flavonoids, especially baicalin, can restore cardiac health following MIRI, improving cardiac performance, and reducing cardiac damage. These findings underscore the potential of baicalin and baicalein as therapeutic options for MIRI. However, further research and clinical trials are necessary to elucidate their mechanisms fully and to develop baicalin into a viable treatment.

Exploring the Cardiovascular Protective Effects of Baicalin: A Pathway to New Therapeutic Insights

Cardiovascular disorders develop the highest rates of mortality and morbidity worldwide, emphasizing the need for novel pharmacotherapies. The Chinese medicinal plant S. baicalensis has a number of major active components, one of which is called baicalin. According to emerging research, baicalin reduces chronic inflammation, immunological imbalance, lipid metabolism, apoptosis, and oxidative stress. Baicalin improves endothelial function and protects the cardiovascular system from oxidative stress-induced cell injury by scavenging free radicals and inhibiting xanthine oxidase. Therefore, it helps prevent CVD such as hypertension, atherosclerosis, and cardiac arrest. In this review, the therapeutic effects of baicalein are discussed in relation to both the prevention and management of cardiovascular diseases.

Qingre Huoxue decoction attenuates myocardial ischemia‒reperfusion injury by regulating the autophagy‒endoplasmic reticulum stress axis via FAM134B-mediated ER-phagy

Background

Autophagy‒endoplasmic reticulum (ER) stress axis dysregulation is linked to myocardial ischemia‒reperfusion injury (MIRI), which counteracts the benefits of acute myocardial infarction (AMI) reperfusion therapy. Qingre Huoxue decoction (QRHX) improves the short- and long-term prognosis of AMI after percutaneous coronary intervention and alleviates myocardial injury in AMI rats by stimulating autophagy via the PI3K/Akt pathway. We aimed to further explore the efficacy of QRHX in treating MIRI and its regulatory relationship with FAM134B-mediated ER-phagy.

Materials and methods

Rats were administered different concentrations of QRHX for 2 weeks, and then MIRI was induced. Ultra-performance liquid chromatography‒tandem mass spectrometry (UPLC‒MS) was used to examine the levels of the main pharmacological metabolites of the serum of rats treated with QRHX. H9c2 cells were pretreated with QRHX-mediating serum (QRHX-MS) for 24 h before being exposed to hypoxia/reoxygenation (H/R). The mechanisms underlying the effects of QRHX-MS were further studied via rescue experiments involving FAM134B knockdown. The myocardial infarct size, cardiac function, morphology and the expression of apoptosis-, autophagy-, and ER stress-related proteins and genes were assessed. The colocalization of autophagosomes with lysosomes and the localization of proteins involved in ER-phagy or autophagic flux was examined.

Results

QRHX decreased the myocardial infarct size and oxidative stress, improved cardiac function and alleviated morphological changes in a dose-dependent manner in MIRI rats by promoting autophagic flux to inhibit ER stress and ER stress-related apoptosis, which was related to FAM134B-mediated ER-phagy, as revealed by autophagy analysis. UPLC‒MS analysis of QRHX-MS revealed 20 major active metabolites of QRHX-MS, including baicalin, cryptotanshinone, 3,4-dihydroxybenzaldehyde and caffeic acid. QRHX-MS attenuated H/R-induced cardiomyocyte injury and apoptosis by increasing autophagic flux to suppress ER stress and ER stress-related apoptotic protein and gene expression. When autophagic flux was inhibited or FAM134B was knocked down in H9c2 cells followed by QRHX-MS pretreatment, the protective effect of QRHX was partially reversed.

Conclusion

QRHX alleviates myocardial injury, apoptosis and infarct size expansion in MIRI by regulating the autophagy‒ER stress axis via FAM134B-mediated ER-phagy.

The potential of flavonoids to mitigate cellular senescence in cardiovascular disease

Aging is one of the most significant factors affecting cardiovascular health, with cellular senescence being a central hallmark. Senescent cells (SCs) secrete a specific set of signaling molecules known as the senescence-associated secretory phenotype (SASP). The SASP has a remarkable impact on age-associated diseases, particularly cardiovascular diseases (CVD). Targeting SCs through anti-aging therapies represents a novel strategy to effectively retard senescence and attenuate disease progression. Accumulating evidence demonstrates that the flavonoids, widely presented in fruits and vegetables worldwide, can delay or treat CVD via selectively eliminating SCs (senolytics) and modulating SASPs (senomorphics). Nevertheless, only sporadic research has illustrated the application of flavonoids in targeting SCs for CVD, which requires further exploration. This review recapitulates the hallmarks and key molecular mechanisms involved in cellular senescence, then summarizes senescence of different types of cardiac cells and describes the mechanisms by which cellular senescence affects CVD development. The discussion culminates with the potential use of flavonoids via exerting their biological effects on cellular senescence to reduce CVD incidence. This summary will provide valuable insights for cardiovascular drug design, development and clinical applications leveraging flavonoids.

Protective effects of baicalin against phenylarsine oxide-induced cytotoxicity in human skin keratinocytes

Phenylarsine oxide (PAO) is a known environmental pollutant and skin keratinocytes are most seriously affected. Baicalin (BCN) was reported to have antioxidant and anti-inflammatory effects, but its protective effect against PAO toxicity is unknown. This study aimed at exploring whether baicalin can reverse the toxicity of human epidermal keratinocytes that are subjected to PAO exposure and underlying mechanisms. In silico analysis from a publicly accessible HaCaT cell transcriptome dataset exposed to chronic Arsenic showed significant differential expression of several genes, including the genes related to DNA replication. Later, we performed in vitro experiments, in which HaCaT cells were exposed to PAO (500 nM) in the existence of BCN (10-50 µM). Treatment of PAO alone induces the JNK, p38 and caspase-3 activation, which were engaged in the apoptosis induction, while the activity of AKT was significantly inhibited, which was engaged in the suppression of apoptosis. PAO suppressed SIRT3 expression and induced intracellular reactive oxygen species (ROS), causing a marked reduce in cell viability and apoptosis. However, BCN treatment restored the PAO-induced suppression of SIRT3 and AKT expression, reduced intracellular ROS generation, and markedly suppressed both caspase-3 activation and apoptosis induction. However, the protective effect of BCN was significantly attenuated after pretreatment with nicotinamide, an inhibitor of SIRT3. These findings indicate that BCN protects against cell death induced by PAO via inhibiting excessive intracellular ROS generation via restoring SIRT3 activity and reactivating downstream AKT pathway. In this study, we firstly shown that BCN is an efficient drug to prevent PAO-induced skin cytotoxicity, and these findings need to be confirmed by in vivo and clinical investigations.

Molecular mechanisms of flavonoids in myocardial ischemia reperfusion injury: Evidence from in-vitro and in-vivo studies

OBJECTIVES

Flavonoids are polyphenolic compounds found in a wide range of foods, including fruits, vegetables, tea plants, and other natural products. They have been mainly classified as flavanols, flavonols, flavones, isoflavones, flavanones, and flavanonols. In this comprehensive review, we will discuss preclinical pieces of evidence on the potential of flavonoids for the prevention/treatment of myocardial ischemia-reperfusion (IR) injury.

KEY FINDINGS

In-vitro and in-vivo studies have shown that flavonoids play an important role in preventing ischemic heart disease (IHD). They possess strong anti-oxidant, anti-inflammatory, anti-bacterial, anti-thrombotic, anti-apoptotic, and anti-carcinogenic activities. In addition, at a molecular level, flavonoids also modulate various pathways like MAPK, NFκB etc. to confer beneficial effects.

SUMMARY

The current review of flavonoids in myocardial ischemia-reperfusion injury furnishes updated information that could drive future research. The in-vitro and in-vivo experiments have demonstrated various favourable pharmacological properties of flavonoids. This review provides valuable information to conduct clinical studies, validating the safety aspects of flavonoids in the clinical domain.

Inflammation in diabetes complications: molecular mechanisms and therapeutic interventions

At present, diabetes mellitus (DM) has been one of the most endangering healthy diseases. Current therapies contain controlling high blood sugar, reducing risk factors like obesity, hypertension, and so on; however, DM patients inevitably and eventually progress into different types of diabetes complications, resulting in poor quality of life. Unfortunately, the clear etiology and pathogenesis of diabetes complications have not been elucidated owing to intricate whole-body systems. The immune system was responsible to regulate homeostasis by triggering or resolving inflammatory response, indicating it may be necessary to diabetes complications. In fact, previous studies have been shown inflammation plays multifunctional roles in the pathogenesis of diabetes complications and is attracting attention to be the meaningful therapeutic strategy. To this end, this review systematically concluded the current studies over the relationships of susceptible diabetes complications (e.g., diabetic cardiomyopathy, diabetic retinopathy, diabetic peripheral neuropathy, and diabetic nephropathy) and inflammation, ranging from immune cell response, cytokines interaction to pathomechanism of organ injury. Besides, we also summarized various therapeutic strategies to improve diabetes complications by target inflammation from special remedies to conventional lifestyle changes. This review will offer a panoramic insight into the mechanisms of diabetes complications from an inflammatory perspective and also discuss contemporary clinical interventions.

Roles of flavonoids in ischemic heart disease: Cardioprotective effects and mechanisms against myocardial ischemia and reperfusion injury

BACKGROUND

Flavonoids are extensively present in fruits, vegetables, grains, and medicinal plants. Myocardial ischemia and reperfusion (MI/R) comprise a sequence of detrimental incidents following myocardial ischemia. Research indicates that flavonoids have the potential to act as cardioprotective agents against MI/R injuries. Several specific flavonoids, e.g., luteolin, hesperidin, quercetin, kaempferol, and puerarin, have demonstrated cardioprotective activities in animal models.

PURPOSE

The objective of this review is to identify the cardioprotective flavonoids, investigate their mechanisms of action, and explore their application in myocardial ischemia.

METHODS

A search of PubMed database and Google Scholar was conducted using keywords "myocardial ischemia" and "flavonoids". Studies published within the last 10 years reporting on the cardioprotective effects of natural flavonoids on animal models were analyzed.

RESULTS

A total of 55 natural flavonoids were identified and discussed within this review. It can be summarized that flavonoids regulate the following main strategies: antioxidation, anti-inflammation, calcium modulation, mitochondrial protection, ER stress inhibition, anti-apoptosis, ferroptosis inhibition, autophagy modulation, and inhibition of adverse cardiac remodeling. Additionally, the number and position of OH, 3'4'-catechol, C2=C3, and C4=O may play a significant role in the cardioprotective activity of flavonoids.

CONCLUSION

This review serves as a reference for designing a daily diet to prevent or reduce damages following ischemia and screening of flavonoids for clinical application.

Baicalin exerts neuroprotective actions by regulating the Nrf2-NLRP3 axis in toxin-induced models of Parkinson's disease

Baicalin, a potent anti-oxidative and anti-inflammatory flavonoid compound derived from Scutellaria baicalensis, has emerged as a neuroprotective agent. However, the mechanisms by which baicalin is neuroprotective in Parkinson's disease (PD) remain unclear. In this research, α-syn/MPP+ and MPTP were used to establish PD models in BV2 cells and C57BL/6 mice, respectively. The effect and mechanism of action of baicalin in PD were investigated by Western blotting, RT-qPCR, ELISA, Immunohistochemistry (IHC) staining, Immunofluorescence (IF) staining, HPLC and methods. Results demonstrate that baicalin mitigates oxidative stress, microglia activation and inflammatory response caused by α-syn/MPP+ and MPTP. It protects against dopaminergic neuron loss and relieves motor deficits. Meanwhile, baicalin not only significantly up-regulates the expression of Nrf2 and its downstream antioxidant enzyme, but also suppresses the activation of NLRP3 inflammasome simultaneously. Notably, the beneficial effects of baicalin in PD treatment are blocked by Nrf2 knockdown. This research reveals that baicalin may exert neuroprotective effects in PD treatment by suppressing the activation of NLRP3 inflammasome and it is dependent on the Nrf2-mediated antioxidative response.

Mechanism Repositioning Based on Integrative Pharmacology: Anti-Inflammatory Effect of Safflower in Myocardial Ischemia–Reperfusion Injury

Safflower (Carthamus tinctorius. L) possesses anti-tumor, anti-thrombotic, anti-oxidative, immunoregulatory, and cardio-cerebral protective effects. It is used clinically for the treatment of cardio-cerebrovascular disease in China. This study aimed to investigate the effects and mechanisms of action of safflower extract on myocardial ischemia–reperfusion (MIR) injury in a left anterior descending (LAD)-ligated model based on integrative pharmacology study and ultra-performance liquid chromatography–quadrupole time-of-flight-tandem mass spectrometer (UPLC-QTOF-MS/MS). Safflower (62.5, 125, 250 mg/kg) was administered immediately before reperfusion. Triphenyl tetrazolium chloride (TTC)/Evans blue, echocardiography, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay, lactate dehydrogenase (LDH) ability, and superoxide dismutase (SOD) levels were determined after 24 h of reperfusion. Chemical components were obtained using UPLC-QTOF-MS/MS. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting were used to analyze mRNA and protein levels, respectively. Safflower dose-dependently reduced myocardial infarct size, improved cardiac function, decreased LDH levels, and increased SOD levels in C57/BL6 mice. A total of 11 key components and 31 hub targets were filtered based on the network analysis. Comprehensive analysis indicated that safflower alleviated inflammatory effects by downregulating the expression of NFκB1, IL-6, IL-1β, IL-18, TNFα, and MCP-1 and upregulating NFκBia, and markedly increased the expression of phosphorylated PI3K, AKT, PKC, and ERK/2, HIF1α, VEGFA, and BCL2, and decreased the level of BAX and phosphorylated p65. Safflower shows a significant cardioprotective effect by activating multiple inflammation-related signaling pathways, including the NFκB, HIF-1α, MAPK, TNF, and PI3K/AKT signaling pathways. These findings provide valuable insights into the clinical applications of safflower.

Wogonoside preserves against ischemia/reperfusion-induced myocardial injury by suppression of apoptosis, inflammation, and fibrosis via modulating Nrf2/HO-1 pathway

OBJECTIVE

Myocardial ischemia/reperfusion (I/R) injury occurs after restoring blood supply, which brings about extra damage to heart tissue. Thus, exploring protection measures and underlying mechanisms appear to be particularly important. In this study, we investigated the cardioprotection of wogonoside against I/R injury in mice and further uncovered its mechanism.

METHODS

Mice model of myocardial I/R injury was established by left anterior descending coronary artery (LAD). Before modeling, mice were administered the wogonoside (10, 20, and 40 mg/kg) for 7 d. To evaluate the effect of wogonoside through nuclear factor E2-associated factor 2/heme oxygenase-1 (Nrf2/HO-1) pathway, sh-Nrf2 was transfected into wogonoside-treated I/R mice. Subsequently, echocardiography detection, HE staining, western blotting, ELISA, TUNEL assay, and MASSON assay were utilized to evaluate the degree of myocardial injury.

RESULTS

In I/R group, mice had severe myocardial injury, however, pretreatment of wogonoside at doses of 20 and 40 mg/kg ameliorated the cardiac function, as evidenced by improving hemodynamic parameters. Besides, wogonoside could relieved the abnormality of cardiomyocytes structure, inflammatory reaction, apoptosis, and myocardial fibrosis. Importantly, wogonoside activated the Nrf2/HO-1 pathway, as demonstrated by increasing Nrf2 expression in nucleus and its downstream genes including HO-1 and NADPH quinone oxidoreductase-1 (NQO1). However, effects of wogonoside on cardioprotection were abolished by sh-Nrf2.

CONCLUSIONS

Wogonoside exerted the protective role against I/R-induced myocardial injury by suppression of apoptosis, inflammation, and fibrosis via activating Nrf2/HO-1 pathway.

Evidence construction of baicalin for treating myocardial ischemia diseases: A preclinical meta-analysis

BACKGROUND

Baicalin, a flavonoid glycoside isolated from Scutellaria baicalensis Georgi, has shown potential pharmacological effects on myocardial ischemia diseases. Nevertheless, systematic preclinical studies on baicalin in the treatment of ischemic diseases are scarce.

PURPOSE

To assess the efficacy and potential mechanisms of baicalin in myocardial ischemia (RI), myocardial ischemia-reperfusion (IR) injury and myocardial infarction (MI) animal models for future clinical research.

METHODS

Preclinical studies published prior to August 27th, 2022 were retrieved from PubMed, Embase, Web of Science and Cochrane Library. CAMARADES list was used to evaluate the quality of included researches. Meta-analyses of cardiac pathology and function parameters, myocardial injury markers and other indicators were performed by STATA 15.0 software. Potential mechanisms are categorized and summarized. Dose-response interval analyses were used to analyze the dose-response relationship between baicalin and myocardial ischemia disease.

RESULTS

Fourteen studies and 222 animals were included in the analysis. The results showed that compared with the control group, baicalin could reduce myocardial infarction size associated with cardiac pathological condition and the corresponding cardiac pathological index containing CK-MB, CK and cTnT. Additionally, heart function indicators including LVSP, LVFS, LVEF, -dp/dt max, dp/dt max were increased by baicalin. As for subgroup analyses, baicalin also demonstrated certain effect on CK-MB and LVSP by administration method or stage. Furthermore, it displayed obvious effect on myocardial ischemia diseases when the dose is maintained at 100-150 mg/kg based on dosage analyses.

CONCLUSION

Based on the relevant literature retrieved, this is the first meta-analysis on baicalin in treating myocardial ischemia diseases. Notably, we linked the dynamic development of the disease and discussed it pertinently, from RI, IR injury to MI. Baicalin exhibits positive effects on myocardial ischemia diseases (especially when the dose is 100-150 mg/kg), which is achieved by regulating key pathological indicators and various signaling pathways.

Inhibition of Myocardial Cell Apoptosis Is Important Mechanism for Ginsenoside in the Limitation of Myocardial Ischemia/Reperfusion Injury

Ischemic heart disease has a high mortality, and the recommended therapy is reperfusion. Nevertheless, the restoration of blood flow to ischemic tissue leads to further damage, namely, myocardial ischemia/reperfusion injury (MIRI). Apoptosis is an essential pathogenic factor in MIRI, and ginsenosides are effective in inhibiting apoptosis and alleviating MIRI. Here, we reviewed published studies on the anti-apoptotic effects of ginsenosides and their mechanisms of action in improving MIRI. Each ginsenoside can regulate multiple pathways to protect the myocardium. Overall, the involved apoptotic pathways include the death receptor signaling pathway, mitochondria signaling pathway, PI3K/Akt signaling pathway, NF-κB signaling pathway, and MAPK signaling pathway. Ginsenosides, with diverse chemical structures, regulate different apoptotic pathways to relieve MIRI. Summarizing the effects and mechanisms of ginsenosides contributes to further mechanism research studies and structure-function relationship research studies, which can help the development of new drugs. Therefore, we expect that this review will highlight the importance of ginsenosides in improving MIRI via anti-apoptosis and provide references and suggestions for further research in this field.

Promising Therapeutic Candidate for Myocardial Ischemia/Reperfusion Injury: What Are the Possible Mechanisms and Roles of Phytochemicals?

Percutaneous coronary intervention (PCI) is one of the most effective reperfusion strategies for acute myocardial infarction (AMI) despite myocardial ischemia/reperfusion (I/R) injury, causing one of the causes of most cardiomyocyte injuries and deaths. The pathological processes of myocardial I/R injury include apoptosis, autophagy, and irreversible cell death caused by calcium overload, oxidative stress, and inflammation. Eventually, myocardial I/R injury causes a spike of further cardiomyocyte injury that contributes to final infarct size (IS) and bound with hospitalization of heart failure as well as all-cause mortality within the following 12 months. Therefore, the addition of adjuvant intervention to improve myocardial salvage and cardiac function calls for further investigation. Phytochemicals are non-nutritive bioactive secondary compounds abundantly found in Chinese herbal medicine. Great effort has been put into phytochemicals because they are often in line with the expectations to improve myocardial I/R injury without compromising the clinical efficacy or to even produce synergy. We summarized the previous efforts, briefly outlined the mechanism of myocardial I/R injury, and focused on exploring the cardioprotective effects and potential mechanisms of all phytochemical types that have been investigated under myocardial I/R injury. Phytochemicals deserve to be utilized as promising therapeutic candidates for further development and research on combating myocardial I/R injury. Nevertheless, more studies are needed to provide a better understanding of the mechanism of myocardial I/R injury treatment using phytochemicals and possible side effects associated with this approach.

Baicalin protects against insulin resistance and metabolic dysfunction through activation of GALR2/GLUT4 signaling

BACKGROUND

Type 2 diabetes mellitus is a complex metabolic disorder associated with obesity, glucose intolerance and insulin resistance. Activation of GALR2 has been proposed as a therapeutic target for the treatment of insulin resistance. The previous studies showed that baicalin could mitigate insulin resistance, but the detailed mechanism of baicalin on insulin resistance has not been fully explored yet.

PURPOSE

In the present study, we evaluated whether baicalin mitigated insulin resistance via activation of GALR2 signaling pathway.

STUDY DESIGN/METHODS

Baicalin (25 mg/kg/d and 50 mg/kg/d) and/or GALR2 antagonist M871 (10 mg/kg/d) were injected individually or in combinations into obese mice once a day for three weeks, and normal and GALR2 knockdown myotubes were treated with baicalin (100 μM and 400 μM) or metformin (4 mM) in the absence or presence of M871 (800 nM) for 12 h, respectively. The molecular mechanism was explored in skeletal muscle and L6 myotubes.

RESULTS

The present findings showed that baicalin mitigated hyperglycemia and insulin resistance and elevated the levels of PGC-1α, GLUT4, p-p38MAPK, p-AKT and p-AS160 in skeletal muscle of obese mice. Strikingly, the baicalin-induced beneficial effects were abolished by GALR2 antagonist M871 in obese mice. In vitro, baicalin dramatically augmented glucose consumption and the activity of PGC1α-GLUT4 axis in myotubes through activation of p38MAPK and AKT pathways. Moreover, baicalin-induced elevations in glucose consumption related genes were abolished by GALR2 antagonist M871 or silencing of GALR2 in myotubes.

CONCLUSIONS

The present study for the first time demonstrated that baicalin protected against insulin resistance and metabolic dysfunction mainly through activation of GALR2-GLUT4 signal pathway. Our findings identified that activation of GALR2-GLUT4 signal pathway by baicalin could be a new therapeutic approach to treat insulin resistance and T2DM in clinic.

The Role of Ferroptosis in Cardiovascular Disease and Its Therapeutic Significance

Cardiovascular diseases (CVDs) are the leading cause of deaths worldwide with regulated cell death playing an important role in cardiac pathophysiology. However, the classical mode of cell death cannot fully explain the occurrence and development of heart disease. In recent years, much research has been performed on ferroptosis, a new type of cell death that causes cell damage and contributes to the development of atherosclerosis, myocardial infarction, heart failure, and other diseases. In this review, we discuss the role of different organelles in ferroptosis and also focus on the relationship between autophagy and ferroptosis. Additionally, we describe the specific mechanism by which ferroptosis contributes to the development of CVD. Finally, we summarize the current research on ferroptosis-related pathway inhibitors and the applications of clinically beneficial cardiovascular drugs.

Baicalin Prevents Myocardial Ischemia/Reperfusion Injury Through Inhibiting ACSL4 Mediated Ferroptosis

Baicalin is a natural flavonoid glycoside that confers protection against myocardial ischemia/reperfusion (I/R) injury. However, its mechanism has not been fully understood. This study focused on elucidating the role of ferroptosis in baicalin-generated protective effects on myocardial ischemia/reperfusion (I/R) injury by using the myocardial I/R rat model and oxygen–glucose deprivation/reoxygenation (OGD/R) H9c2 cells. Our results show that baicalin improved myocardial I/R challenge–induced ST segment elevation, coronary flow (CF), left ventricular systolic pressure , infarct area, and pathological changes and prevented OGD/R-triggered cell viability loss. In addition, enhanced lipid peroxidation and significant iron accumulation along with activated transferrin receptor protein 1 (TfR1) signal and nuclear receptor coactivator 4 (NCOA4)-medicated ferritinophagy were observed in in vivo and in vitro models, which were reversed by baicalin treatment. Furthermore, acyl-CoA synthetase long-chain family member 4 (ACSL4) overexpression compromised baicalin-generated protective effect in H9c2 cells. Taken together, our findings suggest that baicalin prevents against myocardial ischemia/reperfusion injury via suppressing ACSL4-controlled ferroptosis. This study provides a novel target for the prevention of myocardial ischemia/reperfusion injury.

TRIM27 protects against cardiac ischemia-reperfusion injury by suppression of apoptosis and inflammation via negatively regulating p53

Myocardial ischemia/reperfusion (MI/R) has high morbidity and mortality worldwide, but the underlying mechanisms have not been entirely understood. TRIM27 is one of the Tri-domain proteins (TRIM) family proteins with crucial roles in numerous life processes. In the study, we attempted to explore the effects of heart-conditional knockout of TRIM27 (TRIM27^cKO) on MI/R progression both in vivo and in vitro. Our results showed that TRIM27 was strongly decreased in murine hearts with MI/R injury and in cardiomyocytes with hypoxic reoxygenation (HR) treatment. TRIM27^cKO could further accelerate the infarction size and cardiac dysfunction in MI/R mice. Function study demonstrated that heart-selective TRIM27 deletion significantly aggravated apoptosis in hearts of MI/R mice through enhancing Caspase-3 activities. Moreover, inflammatory response due to MI/R injury was remarkably exacerbated in TRIM27^cKO mice by strengthening nuclear factor κB (NF-κB) activation. In addition, p53 expression levels were dramatically up-regulated in hearts of MI/R mice and cardiomyocytes with HR treatment, which were further aggravated by TRIM27^cKO. Intriguingly, we found that TRIM27 could interact with p53 and promote its ubquitination. Of note, suppressing p53 remarkably ameliorated TRIM27^cKO-intensified apoptotic cell death and inflammation in HR-treated cardiomyocytes. Taken together, all these findings revealed that TRIM27/p53 axis may be involved in MI/R progression, and thus could be a therapeutic target for this disease treatment.

Baicalin triggers apoptosis, inhibits migration, and enhances anti-tumor immunity in colorectal cancer via TLR4/NF-κB signaling pathway

Aberrant activation of the nuclear factor-kappa B (NF-κB) signaling pathway is closely implicated in colorectal cancer (CRC) growth, metastasis, and immune escape. In the present study, we reported natural derived compound of baicalin (BA), an efficient inhibitor of NF-κB, with good anti-tumor effect on CRC. CCK8 and colony formation assays showed that Baicalin significantly inhibit viability and proliferation in HCT-116 and CT26 cells. Additionally, Baicalin dramatically triggers mitochondria-mediated apoptosis in both HCT-116 and CT-26 cells, which is evidenced by loss of mitochondrial membrane potential and elevated cellular reactive oxygen species level. Treatment with Baicalin suppresses migration and invasion of CT26 cells by impairing TLR4/NF-κB signaling pathway. What's more, administration of Baicalin significantly retarded tumor growth rate in a subcutaneous xenograft tumor mouse model of CT26 cells. Treatment with Baicalin could ameliorate tumor immunosuppressive environment by downregulation of PD-L1 expression and proportion of myeloid-derived suppressor cells (MDSCs) and upregulation of percent of CD4⁺ and CD8⁺ T cells in CT26 tumors, thus improving anti-tumor immunity. In conclusion, our study demonstrated that baicalin triggers apoptosis, inhibits migration, and enhances anti-tumor immunity in colorectal cancer via TLR4/NF-κB signaling pathway, suggesting it might serve as a potential candidate drug for the treatment of CRC. PRACTICAL APPLICATIONS: In the present study, we reported natural derived compound of baicalin (BA), an efficient inhibitor of NF-κB, with good anti-tumor effect on CRC. We demonstrated that baicalin triggers mitochondria-mediated apoptosis, inhibits migration, and improves anti-tumor immunity in colorectal cancer via TLR4/NF-κB signaling pathway.

The Protective of Baicalin on Myocardial Ischemia-Reperfusion Injury

BACKGROUND

The aim of this study was to explore the inhibitory effect of baicalin on myocardial apoptosis induced by Ischemia-Reperfusion (I/R).

METHODS

Sprague Dawley rats' heart and myocardial cells I/R model were established in vivo and vitro, then 100 mg/kg and 10 μmol/l baicalin were administrated, respectively. The experiment was randomly divided into 4 groups (n=10): Control; I/R; IR+DMEM; and I/R+baicalin groups. Postoperation, the Left Ventricular (LV) End-Diastolic Pressure (LVEDP), the maximum velocity of LV contraction (dP/dtmax) and the maximum velocity of LV diastole (dP/dtmin) were recorded by the transthoracic echocardiography; the myocardial apoptosis percentage was analyzed by Annexin VFITC/ PI and TUNEL staining, and the apoptosis gene and protein were detected by RT-PCR and western blot. Furthermore, the protein expression of the calcium-sensing receptor (CaSR) and ERK1/2 phosphorylation were observed by western blot and Fura-2-acetoxymethyl ester. Moreover, primary rats' cardiomyocytes were cultured and ERK1/2 specific inhibitor PD98059 was added to the culture medium. The cell survival rate, vitality and apoptosis were detected by MTT, lactate dehydrogenase (LDH) and TUNEL staining assay Kit, respectively.

RESULTS

Our present study showed that baicalin significantly improved LV hemodynamic parameters and myocardial apoptosis in myocardial I/R injury rats. Furthermore, we found that baicalin could down-regulate the protein expression of CaSR, but up-regulate the protein expression of ERK1/2. Furthermore, when the cells were pretreated with ERK1/2 inhibitor PD98059, the cells survival rate significantly decreased, but LDH activity and apoptosis significantly increased. The results indicated that the effect of baicalin on myocardial I/R injury could be inhibited by ERK1/2 inhibitor.

CONCLUSION

In conclusion, our data suggests that baicalin attenuates I/R-induced myocardial injury maybe through the suppression of the CaSR/ERK1/2 signaling pathway.

Baicalin regulates macrophages polarization and alleviates myocardial ischaemia/reperfusion injury via inhibiting JAK/STAT pathway

CONTEXT

Baicalin is an active compound which demonstrates cardioprotection effects against myocardial ischaemia/reperfusion injury (MI/RI).

OBJECTIVE

To investigate how baicalin protects against myocardial injury and to explore its potential mechanism. We hypothesized that baicalin-modulated macrophages change from M1 (pro-inflammatory subset) to M2 (anti-inflammatory subset) under I/R stress.

MATERIALS AND METHODS

We established an ischaemia/reperfusion (I/R) model using Sprague Dawley (SD) rat, then baicalin was intragastric administration (20, 60 or 120 mg/kg) for 24 h. The rats were randomly divided into five groups (n = 10): control, I/R, I/R + baicalin (20 mg/kg), I/R + baicalin (60 mg/kg) and I/R + baicalin (120 mg/kg). Cardiac function was detected by echocardiography, HE staining and ELISA, respectively. Macrophage phenotype was examined by flow cytometry. Furthermore, IHC, qRT-PCR and WB were employed to analyse the related mechanisms.

RESULTS

The study showed that baicalin (20, 60 or 120 mg/kg) significantly improved cardiac function and impeded cardiac apoptosis in rats. In addition, the repair of myocardial morphology (reduced neutrophil infiltration) further confirmed its cardiacprotective effect. Moreover, baicalin effectively decreased iNOS, IL-1β and IL-6, and up-regulated Arg-1, IL-10 and TGF-β via changing the macrophage phenotype (from M1 towards M2). Notably, treatment with baicalin also inhibited the phosphorylation levels of JAK2 and STAT3. Discussion and conclusions: It was confirmed that baicalin alleviated post-I/R myocardial injury and reduced inflammation via JAK/STAT pathway, and baicalin treatment might be recommended as a new approach for myocardial ischaemic complications.

Regulatory Mechanisms of Baicalin in Cardiovascular Diseases: A Review

Cardiovascular diseases (CVDs) is the leading cause of high morbidity and mortality worldwide, which emphasizes the urgent necessity to develop new pharmacotherapies. In eastern countries, traditional Chinese medicine Scutellaria baicalensis Georgi has been used clinically for thousands of years. Baicalin is one of the main active ingredients extracted from Chinese herbal medicine S. baicalensis. Emerging evidence has established that baicalin improves chronic inflammation, immune imbalance, disturbances in lipid metabolism, apoptosis and oxidative stress. Thereby it offers beneficial roles against the initiation and progression of CVDs such as atherosclerosis, hypertension, myocardial infarction and reperfusion, and heart failure. In this review, we summarize the pharmacological features and relevant mechanisms by which baicalin regulates CVDs in the hope to reveal its application for CVDs prevention and/or therapy.

Diosmetin exerts cardioprotective effect on myocardial ischaemia injury in neonatal rats by decreasing oxidative stress and myocardial apoptosis

Myocardial injury caused by the myocardial ischaemia (MI) is still a troublesome condition in the clinic, including apoptosis, oxidative stress and inflammation. Diosmetin inhibits the cellular apoptosis and inflammatory response and enhances antioxidant activity. So, this study was designed to investigate the cardioprotective effects of diosmetin on MI model neonatal rats. Forty Sprague Dawley (SD) rats 7 days old were randomly divided into five groups. Four groups of rats received diosmetin (50, 100, and 200 mg/kg) or vehicle (MI group) after ischaemia. Another group received vehicle without ischaemia to serve as a control group. Rats were pretreated with diosmetin intraperitoneally for 7 days and intoxicated with isoproterenol (ISO, 85 mg/kg, sc) on the last 2 days. The expression of apoptotic molecules, myocardial systolic function index, antioxidant enzymes and myocardial enzyme was analyzed. Compared with the control group, the proliferation marker proteins of Ki67 were increased significantly (P < .05), the MI group significantly increased the cardiac apoptosis, oxidative stress and myocardial enzymes, and weakened myocardial contractility. The levels of p-P65/P65 were increased significantly (P < .05) with decreased p-AKT/AKT and p-Nrf2/Nrf2 (P < .05). Nevertheless, pretreatment with diosmetin reversed these changes, especially high-dose group. In summary, diosmetin has significant potential as a therapeutic intervention to ameliorate myocardial injury after MI and provides the rationale for further clinical studies.

Baicalin, a Potent Inhibitor of NF-κB Signaling Pathway, Enhances Chemosensitivity of Breast Cancer Cells to Docetaxel and Inhibits Tumor Growth and Metastasis Both In Vitro and In Vivo

Objective

The aim of this study is to investigate the anti-cancer activity and sensibilization of baicalin (BA) against breast cancer (BC) cells.

Methods

The anti-proliferation of BA in BC cell lines was evaluated by MTT and colony formation assays. Apoptotic induction of BA was measured by flow cytometry. Wound-healing and transwell assays were exploited to assess migrated and invasive inhibition of BA. Western-blot and immunofluorescence were used to study mechanisms of anti-migration and sensibilization of BA. Anti-tumor and anti-metastasis effects of BA were evaluated in subcutaneous and pulmonary metastasis mouse model of BC cells.

Results

BA significantly suppressed proliferation and induced apoptosis of BC cells in a concentration- and time-dependent manner. Additionally, BA induced cell apoptosis via the mitochondria-mediated pathway, as evidenced by cellular induction of reactive oxygen species and upregulated expression of the Bax/Bcl-2 ratio. The overall expression and nuclear translocation of NF-κB signaling pathway in BC cells were dramatically inhibited by treatment with BA. BA significantly suppressed abilities of migration and invasion in BC cells. Notably, BA sensitized BC cells to docetaxel (DXL) by suppressing the expression of survivin/Bcl-2. BA also retarded tumor growth and triggered apoptosis of tumor cells in a tumor mouse model of 4T1 cells. Furthermore, pulmonary metastasis of BC cells was distinctly suppressed by BA in a tumor mouse model of 4T1 cells.

Conclusion

BA effectively triggered apoptosis, inhibited metastasis, and enhanced chemosensitivity of BC, implying that BA might serve as a promising agent for the treatment of BC.

Clinical Prescription-Protein-Small Molecule-Disease Strategy (CPSD), A New Strategy for Chinese Medicine Development: A Case Study in Cardiovascular Diseases

Chinese medicine is a national treasure that has been passed down for thousands of years in China. According to the statistics of the World Health Organization, there are currently four billion people in the world who use Chinese medicine to treat diseases, accounting for 80% of the world's total population. However, the obscurity of its theory, its unmanageable quality, its complex compositions, and the unknown effective substances and mechanisms are great obstacles to the internationalization of Chinese medicine. Here, we propose a new strategy for the development of Chinese medicine: the clinical prescription (C)-protein (P)-small-molecule (S)-disease (D) strategy, namely the CPSD strategy. The strategy uses clinical prescriptions as the source of medicine and uses computer simulation technology to find small-molecule drugs targeting therapeutic proteins for treating specific diseases so as to deepen awareness of the value of Chinese medicine. At the same time, this article takes cardiovascular drug development as an example to introduce the application of CPSD, which will be instrumental in the further development, modernization, and internationalization of Chinese medicine.

Therapeutic potential of IKK-β inhibitors from natural phenolics for inflammation in cardiovascular diseases

Cardiovascular disease (CVDs) is a chronic disease with the highest morbidity and mortality in the world. Previous studies have suggested that preventing inflammation serves an efficient role in protection against cardiovascular diseases. Modulation of IKK-β activity can be used to treat and control CVDs associated with chronic inflammation, which targets the phosphorylation of IκB following the release of the RelA complex, and then translocates to the nucleus, eventually triggering the transcription of several genes that induce chemokines, cytokines, and adhesion molecules. Most importantly, the IκB kinase (IKK) complex is involved in transcriptional activation by phosphorylating the inhibitory molecule IkBα, enabling activation of NF-κB. Phenolic compounds possess cardioprotective potential that may be related to modulating inflammatory responses involved in CVDs. The SystemsDock analysis was used to explore whether 38 active compounds inhibit IKK-β activity based on literature. Docking results showed that the top docking score of three chemical compounds were icariin, salvianolic acid B, and plantainoside D in all compounds. Icariin, salvianolic acid B, and plantainoside D are the most promising IKKβ inhibitors. These phytochemicals could be helpful to find the lead compounds on designing and developing novel cardioprotective agents.

Huang-Lian-Jie-Du Decoction Ameliorates Acute Ulcerative Colitis in Mice via Regulating NF-κB and Nrf2 Signaling Pathways and Enhancing Intestinal Barrier Function

Evidence shows that intestinal inflammation, oxidative stress, and injury of mucosal barrier are closely related to the pathogenesis of ulcerative colitis (UC). Huang-lian-Jie-du Decoction (HLJDD) is a well-known prescription of traditional Chinese medicine with anti-inflammatory and antioxidative activities, which may be used to treat UC. However, its therapeutic effect and mechanism are still unclear. In this study, the UC model of BABL/c mice were established by DSS [3.5% (w/v)], and HLJDD was given orally for treatment at the same time. During the experiment, the clinical symptoms of mice were scored by disease activity index (DAI). Besides, the effects of HLJDD on immune function, oxidative stress, colon NF-κB and Nrf2 signaling pathway, and intestinal mucosal barrier function in UC mice were also investigated. The results showed that HLJDD could alleviate body weight loss and DAI score of UC mice, inhibit colonic shortening and relieve colonic pathological damage, and reduce plasma and colon MPO levels. In addition, HLJDD treatment significantly up-regulated plasma IL-10, down-regulated TNF-α and IL-1β levels, and inhibited the expression of NF-κB p65, p-IκKα/β, and p-IκBα proteins in the colon. Moreover, NO and MDA levels in colon tissues were significantly reduced after HLJDD treatment, while GSH, SOD levels and Nrf2, Keap1 protein expression levels were remarkably elevated. Additionally, HLJDD also protected intestinal mucosa by increasing the secretion of mucin and the expression of ZO-1 and occludin in colonic mucosa. These results indicate that HLJDD could effectively alleviate DSS-induced mice UC by suppressing NF-κB signaling pathway, activating Nrf2 signaling pathway, and enhancing intestinal barrier function.

Shuxuening injection protects against myocardial ischemia-reperfusion injury through reducing oxidative stress, inflammation and thrombosis

Background

Shuxuening injection (SXNI) has a good effect on cardiovascular and cerebrovascular diseases. Here, our study aims to investigate whether SXNI have the protective effect on myocardial ischemia-reperfusion injury (MIRI) and elucidate the mechanism of SXNI's cardiac protection.

Methods

In this experiment, the coronary arteries of Sprague-Dawley (SD) rats were ligated for the induction of a MIRI model. TTC staining and haematoxylin-eosin (HE), as well as troponin I (TnI), lactate dehydrogenase (LDH), aspartate aminotransferase (AST), creatine kinase (CK) and CK-MB levels, were used to detect the protective effect of SXNI. In rat cardiac tissue, superoxide dismutase, catalase, glutathione and malondialdehyde (MDA) activities and glucose-regulated protein 78 (GRP78), calreticulin (CRT), CCAAT/enhancer binding protein homologous protein (CHOP) and caspase-12 expression levels were detected. In rat serum, the levels of inflammatory factors, including high-sensitivity C-reactive protein, monocyte chemoattractant protein-1, tumour necrosis factor-α, interleukin-6 (IL-6) and IL-1β, were measured by Elisa. In the rat arterial tissue, Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) expression was measured by western blot. In the rat plasma, ELISA was used to assay the levels of coagulation and plasmin system indicators, including platelet activating factor, endothelin, tissue factor (TF), plasminogen inhibitor, thromboxane B2, plasma fibrinogen.

Results

The results showed that SXNI can reduce the infarct size of myocardial tissue, decrease the myocardial enzyme and TnI levels and decrease the degree of myocardial damage compared with the model group. Additionally, SXNI can increase the activity of antioxidant enzymes, reduce the MDA level and decrease the GRP78, CRT, CHOP and caspase-12 expression levels. SXNI also decreased the levels of inflammatory cytokines in rat serum, lowered the level of procoagulant molecules in plasma and reduced the TLR4/NF-κB expression.

Conclusions

SXNI has protective effect on MIRI mainly by inhibiting oxidative stress and endoplasmic reticulum stress (ERS), thereby regulating TLR4/NF-κB pathway to reduce inflammation, and lowing procoagulant-related factors levels to reduce the risk of thrombosis.

Revealing Antidepressant Mechanisms of Baicalin in Hypothalamus Through Systems Approaches in Corticosterone- Induced Depressed Mice

Baicalin, the main active flavonoid constituent of Scutellaria baicalensis Georgi, has been reported to exert antidepressant effects. Hypothalamic-pituitary-adrenal (HPA) axis plays important roles in depression. However, antidepressant effect and mechanism of baicalin on HPA axis in hypothalamus are still unknown. In present study, we find baicalin significantly attenuates the increase of immobility time in tail suspension and forced swimming, improves the decrease of spending time in open arms, and restores the aberrant negative feedback of HPA axis in chronic corticosterone (CORT)-induced depressed mice. Moreover, proteomics finds 370 differentially expressed proteins after baicalin treatment, including 114 up-regulation and 256 down-regulation in hypothalamus. Systems biology analysis indicates the functions of differentially expressed proteins focus on phosphoserine binding and phosphorylation, especially participate in GR signaling pathway. Finally, our findings demonstrate that baicalin normalizes hypothalamic GR nuclear translocation via reducing GR phosphorylation to remodel negative feedback of HPA axis in CORT-induced mice.

MiR-27 alleviates myocardial cell damage induced by hypoxia/reoxygenation via targeting TGFBR1 and inhibiting NF-κB pathway

MiR-27 prevents atherosclerosis by inhibiting inflammatory responses induced by lipoprotein lipase. Overexpression of miR-27b attenuates angiotensin-induced atrial fibrosis. Nevertheless, studies have rarely investigated on the effect of miR-27 in cardiomyocyte injury. H9c2 cells were transfected with miR-27 mimic/inhibitor. Then the cell proliferation was tested by MTT assay and the cell apoptosis was detected by flow cytometry. The luciferase activity assay was utilized to analyze the relationship between miR-27 and TGFBR1. Quantificational real-time polymerase chain reaction and western blot were utilized to detect the cardiomyocyte differentiation marker and nuclear factor kappa B (NF-κB) pathway. Our outcomes demonstrated that miR-27 expression was downregulated cardiomyocyte injury subjected to hypoxia/reoxygenation (H/R). Additionally, overexpression of miR-27 could significantly alleviate cardiomyocyte injury by regulating cell activity and apoptosis. The luciferase activity assay confirmed that transforming growth factor ß receptor 1 (TGFBR1) is a direct hallmark of miR-27. Besides, overexpression of miR-27 promoted the expression of TGFBR1 in H/R model. After transfection with miR-27 mimic/inhibitor, the expression of NF-κB pathway-related proteins was decreased/increased. Taken together, our data manifested that miR-27 repressed cardiomyocyte injury induced by H/R via mediating TGFBR1 and inhibiting NF-κB signaling pathway. Furthermore, miR-27/ TGFBR1 might be utilized as hopeful biomarkers for myocardial ischemia diagnosis and treatment.

Novel Aspects of Cardiac Ischemia and Reperfusion Injury Mechanisms

Introduction.The present article, in which a contemporary analysis of the literature on the pathophysiology of ischemic and reperfusion injury (IRI) of the myocardium is presented, focuses on the possible role played by of the calpain system and oxidative stress. Several process development options were proposed, including cytosolic and mitochondrial Ca2+ overload, reactive oxygen stress release, acute inflammatory response and metabolic degradation. The combined effect of all of the above factors produces irreversible ischemic and reperfused damage of cardiomyocytes.Materials and methods.The role of the calpain system in the creation of myocardial IRI was experimentally investigated. It was found that active calpain substrates play a significant role in the processes of cell cycle, apoptosis and differentiation, adversely affecting cardiomyocyte functionality. The calpain system is part of an integrated proteolytic system that is critical to the relationship between the structure and function of the cardiac sarcomere. Uncontrolled activation of calpain is indicated in the pathophysiology of many cardiovascular disorders. As shown by research, inhibitor calpain reduces the size of the zone of infarction following ischemia reperfusion and thus lessens the risk of “stunning” the myocardium. As is known, a consequence of IRI is acute myocardial infarction (AMI), which is a central factor in cardiovascular disease (CVD) and is one of the primary causes of mortality. Understanding the exact pathophysiological mechanisms remains an urgent problem for clinical physicians. To date, the mechanisms of IRI are not fully known, which creates certain difficulties in further treatment and prevention tactics. In addition, myocardial IRI is also an important issue for pathoanatomical service, since sudden coronary death can occur despite timely reperfusion therapy following AMI.Conclusion.The development of strategies for creating conditions that limit the degree of damage to myocardial tissues significantly increases the ability of the heart to withstand ischemic damage.

Baicalin Weakens Staphylococcus aureus Pathogenicity by Targeting Sortase B

Staphylococcus aureus (S. aureus) is a human and other animal pathogen that contributes to the primary etiology of nosocomial pneumonia, a disease with high mortality rates and costs. Treatment of multidrug-resistant S. aureus infection is extremely challenging, and new therapeutic strategies beyond antibiotic treatment are needed. Anti-virulence agents that specifically target the molecular determinants of virulence may be a novel method for treating drug-resistant nosocomial infections. Sortase B (SrtB) is a crucial virulence factor in S. aureus and plays an important role during infection. In this study, we find that baicalin suppresses the activity of SrtB. Minimum inhibitory concentration and growth curve assays confirmed that baicalin has no anti-S. aureus properties. We performed live/dead, lactate dehydrogenase (LDH), adherence, and enzyme-linked immunosorbent assays to confirm that baicalin reduced human alveolar epithelial A549 cell injury caused by S. aureus, reduced the adherence of S. aureus to A549 cells, and significantly attenuated the inflammatory response of mouse macrophage J774 cells to S. aureus. Additionally, we were able to elucidate the binding mechanics and identify the interacting sites of baicalin and SrtB via a molecular dynamics simulation, site-directed mutagenesis, and fluorescence spectroscopy quenching. Finally, we confirmed that baicalin directly binds to the active center of SrtB, and the residues Asn⁹² and Tyr¹²⁸ perform an important function in the interaction of SrtB and baicalin. Taken together, these data indicate that baicalin is a promising candidate to combat S. aureus infections.