Meconopsis horridula Hook. f. & Thomson extract and its alkaloid oleracein E exert cardioprotective effects against acute myocardial ischaemic injury in mice

Protective effects of ginsenoside F2 on isoproterenol-induced myocardial infarction by activating the Nrf2/HO-1 and PI3K/Akt signaling pathways

BACKGROUND

Ginsenoside F2 (GF2) serves as the principal intestinal metabolite resulting from the oral intake of Panax ginseng and Panax quinquefolius, exhibiting antioxidative, hypolipidemic, antitumor, and anti-inflammatory properties. Nevertheless, its effect on myocardial infarction (MI) is still unknown.

PURPOSE

The purpose of this study is to investigate the protective effect and the underlying mechanisms of GF2 against isoproterenol (ISO)-induced MI.

METHODS

ISO-induced H9c2 cardiomyocytes and MI rat models were utilized as in vitro and in vivo models to evaluate the impact of anti-MI of GF2. The underlying mechanisms were investigated using a variety of methodologies, including electrocardiography, Western blot analysis, histopathological examination, immunofluorescence, immunohistochemistry, and ELISA techniques.

RESULTS

In vivo experiments, our results indicated that GF2 significantly ameliorated ISO-induced electrocardiographic (ECG) abnormalities, myocardial fiber necrosis, rupture, fibrosis of myocardial tissues, and suppressed cardiac enzyme activities. Meanwhile, GF2 notably raised the activity of antioxidant enzymes like CAT, GSH, and SOD. Furthermore, it downregulated Keap1 expression level while upregulating NQO1, Nrf2, and HO-1 expression levels. Additionally, GF2 suppressed the expression of the cleaved caspase-3 and pro-apoptotic protein Bax while promoting the expression of anti-apoptotic proteins Bcl-2, p-PI3K, and p-Akt. TUNEL fluorescence results also demonstrated that GF2 effectively inhibited cardiomyocyte apoptosis. Furthermore, consistent with the results of animal experiments, GF2 considerably attenuated ROS generation, changed apoptosis and mitochondrial function, and reduced oxidative stress in ISO-induced H9c2 cardiomyocytes through activating Nrf2/HO-1 and PI3K/Akt signaling pathways.

CONCLUSION

Taken together, GF2 ameliorated MI by preventing cardiocyte apoptosis, oxidative stress, and mitochondrial dysfunction via modulating the Nrf2/HO-1 and PI3K/Akt signaling pathways, showing potential as a treatment strategy for treating MI.

9,9'-epoxylignans from Syringa pinnatifolia: A typical case of stereochemical assignment by a quantum chemical calculation with MAEΔΔδ parameter

In the current study, twenty-two stereochemical 9,9'-epoxylignans including 19 undescribed ones were isolated from the ethanol extract of Syringa pinnatifolia in our continuing effort to understand the overall chemical spectrum of this species. These isolates were structurally elucidated by extensive spectroscopic data analysis, X-ray diffraction, modified Mosher's method, and quantum chemical calculations. Meanwhile, the utilization of 13C NMR calculation and the MAEΔΔδ parameter facilitated the stereochemical assignment of groups of lignan stereoisomers. The 13C NMR data were corrected by the averaged errors at each corresponding carbon position in groups of lignan stereoisomers, which improved the theoretic 13C NMR calculation. The finding of the stereochemical structures of 9,9'-epoxylignans is significant. It is helpful to determine the absolute configurations of molecules with the similar core. In addition, these lignans exhibited potential cardioprotective activities on H9c2 cardiomyocytes in vitro and presented significant antioxidant effect.

Equivalent evaluation and biological ingredients of Syringa pinnatifolia against acute myocardial ischemia in mice

ETHNOPHARMACOLOGICAL RELEVANCE

The peeled roots, stems, and twigs of Syringa pinnatifolia Hemsl., known as Shan-Chen-Xiang (SCX) in Chinese, has the traditional effects such as anti-Khii, clearing heat and relieving pain. It has been clinically applied for the treatment of heart failure and mental abnormalities, and gradually replaced agarwood in Mongolian medicine.

AIM OF STUDY

The present study aims to evaluate whether the key subfraction C (C), a half composition in mass of total ethanol extract (T) of SCX, exerts an equivalent effect against acute myocardial ischemia (AMI) compared to fraction I (I), and what was the potential pharmacologically active constituents of SCX.

MATERIALS AND METHODS

Cardiac function, serum marker enzymes, and myocardial tissue pathology of infarcted mice with ligation of the anterior descending (LAD) branch of the left coronary artery were used to evaluate the anti-AMI effect of C and its equivalent potency to that of I. LCMS-IT-TOF was used to identify the main constituents in C and C-. The new and known compounds were isolated from C by a combination of mass spectrometry and bioactivity-guided fractionation methods, and structures were elucidated by extensive spectroscopic and chemical methods, including calculated 13C NMR data, calculated electronic circular dichroism, and single-crystal X-ray crystallography. The protective effect of isolates against oxidative injury induced by H2O2 in H9c2 cells was evaluated according to a previously reported protocol.

RESULTS

The results of cardiac function, serum marker enzymes and myocardial tissue pathology observations (fosinopril as a positive drug) suggested that C (40 mg/kg, orally administered once a day for 7 days) possessed the anti-AMI effect and was equivalent to that of I, while C- did not show the positive effect. Then, 32 lignans were isolated from C, including the majors (8R,8'R,9S)-4,4'-dihydroxy-3,3',9-trimethoxy-9,9'-epoxylignan (24) and (8R,8'R,9R)-4,4'-dihydroxy-3,3',9-trimethoxy-9,9'-epoxylignan (25), which were confirmed by HPLC and LC-MS characterization. Among them, 15 ones were previously undescribed, including a pair of enantiomers (6a/6b), and 11 ones (1, 2, 6a/6b, 8, 10, 12, 16, 17, 24, and 25) exhibited protective effect against oxidative injury to H9c2 cells at different concentrations (ranged from 0.156 to 80 μM).

CONCLUSION

C (40 mg/kg) exerts cardioprotective effect in mice, which was equivalent to that of I and T. Lignans, including both representative compounds (24, 25) and other undescribed molecules with low content, significantly contribute to the anti-AMI effect of SCX. However, the anti-AMI property assessment of SCX should not exclude the contribution from the representative sesquiterpenoid ZER. Hence, the exploration of the final potential substances in SCX requires further investigation.

Catecholamine Derivatives: Natural Occurrence, Structural Diversity, and Biological Activity

Catecholamines (CAs) are aromatic amines containing a 3,4-dihydroxyphenyl nucleus and an amine side chain. Representative CAs included the endogenous neurotransmitters epinephrine, norepinephrine, and dopamine. CAs and their derivatives are good resources for the development of sympathomimetic or central nervous system drugs, while they also provide ligands important for G-protein coupled receptor (GPCR) research. CAs are of broad interest in the fields of chemical, biological, medical, and material sciences due to their high adhesive capacities, chemical reactivities, metal-chelating abilities, redox activities, excellent biocompatibilities, and ease of degradability. Herein, we summarize CAs derivatives isolated and identified from microorganisms, plants, insects, and marine invertebrates in recent decades, alongside their wide range of reported biological activities. The aim of this review is to provide an overview of the structural and biological diversities of CAs, the regularity of their natural occurrences, and insights toward future research and development pertinent to this important class of naturally occurring compounds.

Lagopsis supina ameliorates myocardial ischemia injury by regulating angiogenesis, thrombosis, inflammation, and energy metabolism through VEGF, ROS and HMGB1 signaling pathways in rats

BACKGROUND

Lagopsis supina (Steph. ex. Willd.) Ikonn.-Gal. is an important traditional Chinese medicine used to treat various ailments. However, its impact on myocardial ischemia (MI) injury remains unknown.

PURPOSE

This research aimed to reveal the therapeutic effect, potential mechanism, and metabolomics of L. supina against MI injury in rats.

METHODS

The therapeutic effects of the ethanolic extract of L. supina (LS) and its four fractions (LSA∼D) on a left anterior descending (LAD) artery occlusion-induced MI model rat were explored. The pharmacodynamics including myocardial infraction area, myocardial tissue pathology and apoptosis, and serum biochemical parameters (CK, CK-MB, CTn-T, SOD, ET-1, NO, eNOS, VEGF, TXB2, 6-keto-PGF1α, TNF-α, IL-6, and CRP) were evaluated. The 24 related protein expressions were detected using western blotting assay. Simultaneously, the qualitative and quantitative analyses of microporous adsorption resin with 30% (LSC) and 60% (LSD) aqueous ethanol fractions were performed using UHPLC-MS and HPLC. Moreover, the serum metabolomics analysis of rats was profiled using UHPLC-MS.

RESULTS

LS exerted remarkable alleviating effect on MI in rats. Importantly, LSC and LSD, two effective fractions of LS, significantly reduced myocardial infraction area, alleviated myocardial tissue pathology and apoptosis, regulated serum biochemical parameters. Furthermore, LSC and LSD markedly up-regulated the levels of VEGF-A, VEGFR-2, PKC, Bcl-2, Nrf2, HO-1, and thrombin, as well as prominently down-regulated the protein expression of Notch 1, p-PI3K, p-PI3K/PI3K, p-Akt, p-Akt/Akt, Bax, cleaved-caspase-3, cleaved-caspase-3/caspase-3, vWF, p-Erk, p-Erk/Erk, HMGB1, p-p38, p-p38/p38, p-p65, and p-p65/p65. A total of 26 candidate biomarkers were significantly regulated by LSC and LSD and they are mainly involved in amino acid metabolism, glycerophospholipid metabolism, and sphingolipid metabolism. Finally, phenylethanols and flavonoids may be major bio-constituents of LSC and LSD against MI.

CONCLUSIONS

This work, for the first time, demonstrated that L. supina had a significant therapeutic effect on MI in rats. Additionally, LSC and LSD, two bio-fractions from L. supina, exerted their potential to ameliorate MI injury by promoting angiogenesis, inhibiting thrombosis, blocking inflammation, and facilitating energy metabolism through promotion of VEGF pathway, as well as suppression of ROS and HMGB1 pathways in rats. These findings suggest that LSC and LSD hold promise as potential therapeutic agents for MI injury in clinical application.

Mechanism by which oleracein E alleviates TNBS-induced ulcerative colitis

OBJECTIVE

This study aimed to investigate the effect of oleracein E (OE) in improving 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced ulcerative colitis (UC).

METHODS

Lipopolysaccharide (LPS) was used to induce a UC cell model, and TNBS was used to induce a UC rat model. ELISA was performed to assess the levels of inflammatory factors (IL-1β, TNF-α, and IL-6). Moreover, the activities of catalase (CAT), myeloperoxidase (MPO), and malonaldehyde (MDA) were detected by kits. Western blotting was performed to assess related proteins of the Nrf2/HO-1 signaling pathway, tight junction protein (ZO-1, Occludin, and claudin-2) expression levels, and apoptosis-related proteins (Bcl2, Bax, and cleaved caspase 3). Flow cytometry was used to analyze ROS levels. The morphology of colon tissues and the apoptosis of cells were detected by HE and TUNEL staining, respectively.

RESULTS

OE significantly increased the activity of CAT and decreased the activity of MPO in LPS-induced Caco-2 cells and TNBS-induced UC rats. However, the levels of IL-1β, IL-6, and TNF-α were markedly reduced both in vivo and in vitro. In addition, OE significantly increased the levels of Nrf2/HO-1 signaling pathway-related proteins and tight junction proteins and inhibited cell apoptosis. HE staining showed that OE significantly decreased the severity of acute TNBS-induced colitis in rats.

CONCLUSION

OE may exert a regulatory effect on ameliorating intestinal barrier injury and reducing inflammation and oxidative stress levels by activating the Nrf2/HO-1 pathway.

The alkaloids of Corydalis hendersonii Hemsl. contribute to the cardioprotective effect against ischemic injury in mice by attenuating cardiomyocyte apoptosis via p38 MAPK signaling pathway

BACKGROUND

There is a characteristic Tibetan folk medicine in China named Corydalis hendersonii Hemsl. (CH) has been used for treatment of cardiovascular related diseases, called "plethora" in Tibetan medicine. Previous studies demonstrated that ethanol extract of CH showed anti-acute myocardial infarction (AMI) effect through inhibiting fibrosis and inflammation. Rich alkaloids fraction (RAF) is isolated from CH, but whether RAF possessing an equivalent effect with the CH ethanol extract and by which mechanism it protects against AMI has not yet reported. The paper aimed to study the potential role of RAF on myocardial injured mice and its underlying mechanism.

MATERIALS AND METHODS

Liquid chromatography mass spectrometry-ion trap-time of flight (LCMS-IT-TOF) was used to analyze the chemical profile and isolate pure compounds. The ligation of left anterior descending (LAD) of coronary artery in mice was used to evaluate the in vivo anti-AMI effect, by dividing into eight groups: Sham, Model, Fosinopril (10 mg/kg, i.g.), total extract (TE, 400 mg/kg, i.g.), poor alkaloids fraction  (PAF, 300 mg/kg, i.g.), and RAF (25, 50, and 100 mg/kg, respectively, i.g.) groups. Echocardiography was used to evaluate mice heart function through the index of left ventricular end-systolic  diameter (LVEDs), left ventricular end-diastolic diameter (LVEDd), fractional shortening (FS) and ejection fraction (EF). We detected the lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) in the serum and the plasma level of angiotensin II (AngII). The apoptosis of mice myocardial tissue was verified by TUNEL assay. The expression of p38 mitogen-activated protein kinases (p38 MAPK), Bcl-2 and Bcl-2-associated X protein (Bax) were detected through immunofluorescence staining, qRT-PCR and western blot in mice heart tissue and H9c2 cells.

RESULTS

Echocardiography data indicated that the values of LVEDd and LVEDs were reduced and the values of FS and EF were improved by TE and RAF significantly. RAF also decreased the levels of LDH, CK-MB and AngII and significantly inhibited inflammatory cells in the marginal zone of myocardial infarction. The TUNEL assay results showed that RAF significantly attenuated cell apoptosis. Immunofluorescence and qRT-PCR assay showed that RAF inhibited p38 MAPK, Bax, and Bcl-2 proteins in mice myocardium. Western blot results validated that the expressions of key proteins were inhibited by RAF. Also, the apoptotic cells and apoptosis-related proteins were dramatically reduced by RAF in vivo and in vitro. Besides, RAF and PAF were analyzed by LCMS-IT-TOF to identify the main compounds and to demonstrate the difference between them. The results showed that a total of 14 alkaloids were identified, which indicated that the isoquinoline alkaloids were the main ingredients in RAF may contributing to the cardioprotective effect in mice.

CONCLUSIONS

RAF improves cardiac function by inhibiting apoptosis via p38 MAPK signaling pathway, and RAF contributes to the effect against myocardial ischemic injury of TE in mice, which provides a substantial reference for the clinical application against ischemia heart disease and quality control of CH.

Diverse lignans with protective effect against hypoxia/oxidative injuries to H9c2 cells from Syringa pinnatifolia Hemsl

A bioactivity-guided fractionation on the phenolic fractions from the peeled stems of Syringa pinnatifolia Hemsl., one of representative Mongolian folk medicine in China, led to the isolation and structural determination of 11 undescribed lignans and 12 known ones. These lignans cover diverse types, among them syringanones A and B represent an unprecedented carbon skeleton (proposed syringanane) and alashanenol A possesses a rare bicyclo [3.3.1]nonadienemethanol core. Their structures were established by extensive spectroscopic data analysis, X-ray diffraction, and quantum chemical calculations. All isolates were evaluated for their cardioprotective activities on H9c2 cardiomyocytes in vitro. The results showed that five lignans exhibited the protective effects against hypoxia-induced injury at the concentrations of 1.2-40 μM and six lignans exhibited anti-oxidative stress injury at 10-40 μM. These findings account to some extend for the traditional therapeutic effects of S. pinnatifolia for the treatment of ischemic heart diseases in clinic.

Diagnostic Value of Convolutional Neural Network Algorithm and High-Sensitivity Cardiac Troponin I Detection Under Machine Learning in Myocardial Infarction

Background: It aimed to the diagnosis and examination of acute myocardial infarction (AMI) using echocardiography under improved convolutional neural network (CNN) algorithm and high-sensitivity (Sen) cardiac troponin I (hs-cTnI) detection. The application effect was also evaluated. Methods: Ninety AMI patients were recruited as the AMI group, and ninety healthy individuals who underwent physical examinations simultaneously were chosen as control (Ctrl) group. Improved CNN algorithm-based echocardiography combined with hs-cTnI detection was applied, and its diagnostic efficiency was evaluated. Results: The optimal dataset scale (ODS), optimal image scale (OIS) and average precision (AP) of the proposed algorithm were better than those of manual labeling, Canny algorithm, and structured edge (SE) algorithm (P < 0.05). The left ventricular ejection fraction (LVEF) of the patients in the AMI group was inferior to that of Ctrl group ((55.09±2.78)%) versus (65.01±3.19)%), the left ventricular end-diastolic dimension (LVEDD) was superior to that of Ctrl group ((54.89±6.56) mm vs. (45.98±5.77) mm), and the cTnI level was also superior to that of Ctrl group ((2.90±0.31) pg/L vs. (0.73±0.42) pg/L) (P < 0.05). The diagnostic Sen (91.89%), specificity (Spe) (81.25%), accuracy (Acc) (90.00%) and consistency (0.56) of echocardiography combined with hs-cTnI were superior to those of single echocardiography or cTnI detection (P < 0.05).

7-Hydroxyflavone Alleviates Myocardial Ischemia/Reperfusion Injury in Rats by Regulating Inflammation

Inflammation is the primary pathological process of myocardial ischemia/reperfusion injury (MI/RI). 7-Hydroxyflavone (HF), a natural flavonoid with a variety of bioactivities, plays a crucial role in various biological processes. However, its cardioprotective effects and the underlying mechanisms of MI/RI have not been investigated. This study aimed to explore whether pretreatment with HF could attenuate MI/RI-induced inflammation in rats and investigate its potential mechanisms. The results showed that pretreatment with HF could significantly improve the anatomic data and electrocardiograph parameters, reduce the myocardial infarct size, decrease markers of myocardial injury (aspartate transaminase, creatine kinase, lactate dehydrogenase, and cardiac troponin I), inhibit inflammatory cytokines (IL-1β, IL-6, and TNF-α), suppress oxidative stress, and recover the architecture of the cardiomyocytes. The cardioprotective effect of HF was connected with the regulation of the MAPK/NF-κB signaling pathway. What is more, molecular docking was carried out to prove that HF could be stably combined with p38, ERK1/2, JNK, and NF-κB. In summary, this is a novel study demonstrating the cardioprotective effects of HF against MI/RI in vivo. Consequently, these results demonstrate that HF can be considered a promising potential therapy for MI/RI.

Characterization of the complete chloroplast genome of the prickly blue poppy Meconopsis horridula Hook. f. & Thomson (Ranunculales: Papaveraceae)

The prickly blue poppy (Meconopsis horridula Hook. f. & Thomson) is a traditional Tibetan medicinal herb with high values. In this study, its chloroplast genome was determined to be 153,761 bp in length with an A + T-biased base composition, and comprises a pair of inverted repeat (IR) regions (26,030 bp), separated by a large single-copy (LSC) region (83,803 bp) and a small single-copy (SSC) region (17,898 bp). A total of 113 gene species were annotated, with 20 of them being completely or partially duplicated and 18 of them harboring one or two introns. Phylogenetic analysis suggests that M. horridula is closely related to Meconopsis racemosa Maxim.