Protective effects of total flavonoids from Clinopodium chinense (Benth.) O. Ktze on myocardial injury in vivo and in vitro via regulation of Akt/Nrf2/HO-1 pathway

Potential Targets of Natural Products for Improving Cardiac Ischemic Injury: The Role of Nrf2 Signaling Transduction

Myocardial ischemia is the leading cause of health loss from cardiovascular disease worldwide. Myocardial ischemia and hypoxia during exercise trigger the risk of sudden exercise death which, in severe cases, will further lead to myocardial infarction. The Nrf2 transcription factor is an important antioxidant regulator that is extensively engaged in biological processes such as oxidative stress, inflammatory response, apoptosis, and mitochondrial malfunction. It has a significant role in the prevention and treatment of several cardiovascular illnesses, since it can control not only the expression of several antioxidant genes, but also the target genes of associated pathological processes. Therefore, targeting Nrf2 will have great potential in the treatment of myocardial ischemic injury. Natural products are widely used to treat myocardial ischemic diseases because of their few side effects. A large number of studies have shown that the Nrf2 transcription factor can be used as an important way for natural products to alleviate myocardial ischemia. However, the specific role and related mechanism of Nrf2 in mediating natural products in the treatment of myocardial ischemia is still unclear. Therefore, this review combs the key role and possible mechanism of Nrf2 in myocardial ischemic injury, and emphatically summarizes the significant role of natural products in treating myocardial ischemic symptoms, thus providing a broad foundation for clinical transformation.

The combination of paeonol, diosmetin-7-O-β-D-glucopyranoside, and 5-hydroxymethylfurfural from Trichosanthis pericarpium alleviates arachidonic acid-induced thrombosis in a zebrafish model

Trichosanthis fruit (TF) is a classic medicinal material obtained from Shandong, China. The peel of this fruit (Trichosanthis pericarpium, TP) is known to exert anti-thrombotic effects. However, the anti-thrombotic active components and mechanisms of TP have yet to be fully elucidated. Combined with zebrafish models and high-performance liquid chromatography (HPLC), this study evaluated the endogenous anti-thrombotic effects with the combination of three compounds from TP. First, we used HPLC to investigate the components in the water extract of TP. Next, we used the zebrafish model to investigate the anti-thrombotic activity of the three compound combinations by evaluating a range of indicators. Finally, the expression of related genes was detected by real-time quantitative polymerase chain reaction (qPCR). HPLC detected a total of eight components in TP water extract, with high levels of paeonol (Pae), diosmetin-7-O-β-D-glucopyranoside (diosmetin-7-O-glucoside), and 5-hydroxymethylfurfural (5-HMF). The most significant anti-thrombotic activity was detected when the Pae: diosmetin-7-O-glucoside:5-HMF ratio was 4:3:3. qPCR analysis revealed that the abnormal expression levels of f2, fga, fgb, vwf, ptgs1, and tbxas1 induced by arachidonic acid (AA) were improved. The combination of Pae, diosmetin-7-O-glucoside, and 5-HMF may alleviate AA-induced thrombosis by inhibiting the inflammatory reaction, coagulation cascade reaction, and arachidonic acid metabolism pathways.

Therapeutic Role of Chinese Medicine Targeting Nrf2/HO-1 Signaling Pathway in Myocardial Ischemia/Reperfusion Injury

Acute myocardial infarction (AMI), characterized by high incidence and mortality rates, poses a significant public health threat. Reperfusion therapy, though the preferred treatment for AMI, often exacerbates cardiac damage, leading to myocardial ischemia/reperfusion injury (MI/RI). Consequently, the development of strategies to reduce MI/RI is an urgent priority in cardiovascular therapy. Chinese medicine, recognized for its multi-component, multi-pathway, and multi-target capabilities, provides a novel approach for alleviating MI/RI. A key area of interest is the nuclear factor E2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway. This pathway is instrumental in regulating inflammatory responses, oxidative stress, apoptosis, endoplasmic reticulum stress, and ferroptosis in MI/RI. This paper presents a comprehensive overview of the Nrf2/HO-1 signaling pathway's structure and its influence on MI/RI. Additionally, it reviews the latest research on leveraging Chinese medicine to modulate the Nrf2/HO-1 pathway in MI/RI treatment.

Undescribed compounds from Clinopodium chinense (Benth.) O. Kuntze and their coagulation activity studies

Four rare compounds (1-4), including one 1,4-epoxy-benzoxepane derivative and one ringed prenylated naphthoquinoid skeleton, as well as one isopimarane-type diterpenoid and one megastigmane-type glycoside, along with three known megastigmane-type glycosides (5-7) were isolated from the ethanol extracts of C. chinense. Their structures were determined on the basis of 1D, 2D NMR, HR-ESI-MS and DP4+ analysis. Meanwhile, the in vitro evaluation indicated that compound 2 and 6 exhibited excellent procoagulant activities, which can significantly shorten prothrombin time (PT) and activated partial thromboplastin time (APTT), respectively.

Protective effect of the total flavonoids from Clinopodium chinense against LPS-induced mice endometritis by inhibiting NLRP3 inflammasome-mediated pyroptosis

ETHNOPHARMACOLOGICAL RELEVANCE

Clinopodium chinense (Benth.) O. Kuntze (C. chinense) is a Chinese herbal medicine used in treating gynecological hemorrhagic diseases for hundreds of years. Flavonoids are one kind of the major components in C. chinense. The flavonoids of C. chinense (TFC) have a vital role in treating endometritis but the underlying therapeutic mechanisms of TFC against endometritis have been rarely reported.

AIM OF THE STUDY

To elucidate the therapeutic effect and possible mechanisms of TFC against lipopolysaccharide (LPS)-induced endometritis in vivo and LPS-induced primary mouse endometrial epithelial cells (MEECs) injury in vitro.

MATERIALS AND METHODS

The holistic phytochemicals of the TFC and TFC-contained serum were screened and identified using UPLC-Q-TOF-MS. The model of endometritis was established by intrauterine injection of LPS (5 mg/mL) into female BALB/c mice, and the model mice were treated with TFC for 7 days. The value of MPO was measured by Myeloperoxidase assay kit, the pathological changes in the endometrium were evaluated using H&E staining and transmission electron microscope (TEM), the secretions of IL-18, IL-1β and TNF-α were determined by ELISA kits, the mRNA expressions of IL-18, IL-1β and TNF-α were determined by RT-PCR assay, and the protein levels of TLR4, IKBα, p-IKBα, p65, p-p65, caspase-1, ASC, NLRP3 and GSDMD were measured by Western blot. Subsequently, MEECs were isolated from the uterus of pregnant female mice, injured by LPS for 24 h and incubated with the TFC-contained serum. Finally, cell viability, LDH release, hoechst 33342/PI staining, immunofluorescence staining, scanning electron microscope observation, ELISA assay, RT-PCR detection and Western blot analysis were carried out to further validate the therapeutic effect and the underlying mechanisms of TFC.

RESULTS

A total of 6 compounds in the plasma of mice after being intragastric administrated of TFC were identified. The results in vivo showed that TFC significantly reduced MPO value and alleviated pathological injury of the endometrium. Furthermore, TFC significantly decreased the serum IL-18, IL-1β and TNF-α levels, and the mRNA levels of IL-18, IL-1β and TNF-α. TFC also inhibited the expressions of TLR4, p-IKBα, p-p65, caspase-1, ASC, NLRP3 and GSDMD. Besides, compared with the model group in MEECs cells, TFC-contained serum prevented pyroptosis, decreased the levels of IL-18 and IL-1β, and inhibited the mRNA expressions of IL-18, IL-1β and GSDMD. TFC-contained serum also reversed the activation of NLRP3 inflammasome caused by nigericin, and restrainted the translocation of NF-κB into nuclear.

CONCLUSIONS

TFC protects mice endometritis from the injury of LPS via suppressing the activation of NLRP3 inflammasome and pyroptosis, the underlying mechanisms of which were related to restraining the TLR4/NF-κB/NLRP3 pathway activation.

Clinopodium chinense Kuntze ameliorates dextran sulfate sodium-induced ulcerative colitis in mice by reducing systematic inflammation and regulating metabolism

ETHNOPHARMACOLOGICAL RELEVANCE

Clinopodium chinense Kuntze (CC), traditional Chinese medicine with anti-inflammatory, anti-diarrheal, and hemostatic activities, has been used to treat dysentery and bleeding diseases for thousands of years, which are similar to the symptoms of ulcerative colitis (UC).

AIM OF THE STUDY

To obtain a novel treatment for UC, an integrated strategy was developed in this study to investigate the effect and mechanism of CC against UC.

MATERIALS AND METHODS

The chemical characterization of CC was scanned by UPLC-MS/MS. Network pharmacology analysis was performed to predict the active ingredients and pharmacological mechanisms of CC against UC. Further, the results of network pharmacology were validated using LPS-induced RAW 264.7 cells and DSS-induced UC mice. The production of pro-inflammatory mediators and biochemical parameters was tested using the ELISA kits. The expression of NF-κB, COX-2, and iNOS proteins was evaluated using Western blot analysis. Body weight, disease activity index, colon length, histopathological examination, and metabolomics analysis in colon tissues were carried out to confirm the effect and mechanism of CC.

RESULTS

Based on the chemical characterization and literature collection, a rich database of ingredients in CC was constructed. Network pharmacology analysis provided five core components as well as revealed that the mechanism of CC against UC was highly related to inflammation, especially the NF-κB signaling pathway. In vitro experiments showed CC could inhibit inflammation by LPS-TLR4-NF-κB-iNOS/COX-2 signaling pathway in RAW264.7 cells. Meanwhile, in vivo experimental results proved that CC significantly alleviated pathological features with increased body weight and colonic length, decreased DAI and oxidative damage, as well as mediated inflammatory factors like NO, PGE2, IL-6, IL-10, and TNF-ɑ. In addition, colon metabolomics analysis revealed CC could restore the abnormal endogenous metabolite levels in UC. 18 screened biomarkers were further enriched in four pathways including Arachidonic acid metabolism, Histidine metabolism, Alanine, aspartate and glutamate metabolism as well as the Pentose phosphate pathway.

CONCLUSION

This study demonstrates that CC could alleviate UC by reducing systematic inflammation and regulating metabolism, which is beneficial for providing scientific data for the development of UC treatment.

A Rapid and Efficient Strategy for Quality Control of Clinopodii herba Encompassing Optimized Ultrasound-Assisted Extraction Coupled with Sensitive Variable Wavelength Detection

Clinopodii herba is a folk herbal medicine for treatments of hemorrhagic disorders. However, there is not even a quantitative standard for clinopodii herba deposited in the Chinese Pharmacopoeia. The development of a strategy for rapid and efficient extraction and simultaneous detection of multiple components in clinopodii herba is therefore of great value for its quality evaluation. Here, a variable wavelength strategy was firstly applied to quantity multiple components by segmental monitoring by UHPLC with diode array detector following ultrasound-assisted extraction. The parameters of ultrasound-assisted extraction were optimized using single factor optimization experiments and response surface methodology by a Box-Behnken design combined with overall desirability. Subsequently, a rapid, efficient, and sensitive method was applied for simultaneous determination of eleven compounds, which represented the major and main types of components in clinopodii herba. Moreover, the performance of the validated method was successfully applied for the quality control of various batches of clinopodii herba and provided sufficient supporting data for the optimum harvest time. The Box-Behnken-optimized ultrasound-assisted extraction coupled with variable wavelength detection strategy established in this work not only improves the quality control of clinopodii herba, but also serves as a powerful approach that can be extended to quality evaluation of other traditional Chinese medicines.

Short-term pretreatment of naringin isolated from Citrus wilsonii Tanaka attenuates rat myocardial ischemia/reperfusion injury

Pretreatment or treatment with anti-apoptotic, anti-inflammatory, or anti-oxidative approaches could be critical for attenuated the severity of myocardial ischemia/reperfusion (I/R) injury. Naringin, a natural flavonoid, plays important roles in inflammation-related diseases. Immature dry fruits of Citrus wilsonii Tanaka (Xiang Yuan) are rich in naringin that can be used as traditional Chinese medicine to treat inflammation-related symptoms. However, its roles in cardioprotective role remain unclear. This study aimed to isolate naringin from Citrus wilsonii Tanaka fruit and tested their cardioprotective effect. The dry fruits of Citrus wilsonii Tanaka were extracted with boiling water and then supernatants were freeze-dried to yield aqueous extract (ZQAE). The extract was chemoprofiled using UPLC-MS/MS to stand for major constituents, and then subjected to different chromatographic separation steps, and naringin was isolated in a high yield. The cardioprotective effects of the aqueous extract of ZQAE and naringin were investigated in a myocardial I/R rat model and to elucidate the mechanism underlying its cardioprotective effect. Our results indicated that 5-day ZQAE and naringin pretreatments both promoted histopathological changes and reduced myocardial enzymes (cTnl, CK-MB, CK and LDH) induced by I/R. Moreover, the 50 mg/kg and 100 mg/kg ZQAE dose pretreatments presented a significantly decreased infarct size as well as myocardial enzyme levels but also inhibited myocardial apoptosis (cleaved-caspase3 protein expression), the inflammatory response (IL-23, IL-6, and TNF-α) and oxidative stress (MDA and SOD). The cardioprotective effect of 5 mg/kg dose of naringin pretreatment is comparable with that of 5 mg/kg drug ditiazem pretreatment. Additionally, naringin pretreatment exhibited striking decreases in the apoptosis index and downregulation of the protein expression levels of cleaved-Caspase3, Bcl2 and Bax. Meanwhile, naringin downregulated HMGB1 expression and upregulated SIRT1 expression in the myocardium. These findings suggest that short-term pretreatments with ZQAE and naringin both protect against myocardial I/R injury by suppressing myocardial apoptosis, the inflammatory response, and oxidative stress. The cardioprotective effect of naringin involves SIRT1 activation and may interact with HMGB1 and inhibit the release of HMGB1.

Bacopa monniera extract mitigates isoproterenol-induced cardiac stress via Nrf2/Keap1/NQO1 mediated pathway

The present study was aimed to investigate the effect of standardised hydroalcoholic extract of Bacopa monniera (BME) against isoproterenol (ISO) induced cardiac stress. Isoproterenol (85 mg/kg body weight) was administered intraperitoneally to induce cardiac stress in rats. Bacopa monniera extract (BME75 and 150 mg/kg) was orally administered for 21 days followed by ISO on 22nd and 23rd experimental days. ISO caused significant cardiac damage, which was concomitant with increased apoptosis and attenuated expressions of Nrf2, HO-1, and regulating apoptotic protein expressions of Bax, Bcl2 and NOS2. Treatment with BME in rats significantly improved cardiac dysfunction by maintaining cardiac rhythm, myocardial integrity. Decreased oxidative stress by restored expressions of Nrf2, NQO1 and HO-1 followed by elevating antioxidant enzymes and total glutathione levels. Our present results suggest that the BME treatment strengthening the endogenous defence system through Nrf2 modulation and played a key role against cardiac oxidative stress induced by ISO in rats.

Mechanism of Action of Flavonoids of Oxytropis falcata on the Alleviation of Myocardial Ischemia–Reperfusion Injury

Oxytropis falcata Bunge is a plant used in traditional Tibetan medicine, with reported anti-inflammatory and antioxidants effects and alleviation of myocardial ischemia reperfusion injury (MIRI). However, the underlying mechanism against MIRI and the phytochemical composition of O. falcata are vague. One fraction named OFF1 with anti-MIRI activity was obtained from O. falcata, and the chemical constituents were identified by ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC–MS). The potential targets and signaling pathways involved in the action of O. falcata against MIRI were predicted by network pharmacology analysis, and its molecular mechanism on MIRI was determined by in vitro assays. The results revealed that flavonoids are the dominant constituents of OFF1. A total of 92 flavonoids reported in O. falcata targeted 213 potential MIRI-associated factors, including tumor necrosis factor (TNF), prostaglandin-endoperoxide synthase 2 (PTGS2), and the NF-κB signaling pathway. The in vitro assay on H9c2 cardiomyocytes subjected to hypoxia/reoxygenation injury confirmed that the flavonoids in OFF1 reduced myocardial marker levels, apoptotic rate, and the inflammatory response triggered by oxidative stress. Moreover, OFF1 attenuated MIRI by downregulating the ROS-mediated JNK/p38MAPK/NF-κB pathway. Collectively, these findings provide novel insights into the molecular mechanism of O. falcata in alleviating MIRI, being a potential therapeutic candidate.

The Research Progress of Trastuzumab-Induced Cardiotoxicity in HER-2-Positive Breast Cancer Treatment

In recent years, the incidence of breast cancer has been increasing on an annual basis. Human epidermal growth factor receptor-2 (HER-2) is overexpressed in 15-20% human breast cancers, which is associated with poor prognosis and a high recurrence rate. Trastuzumab is the first humanized monoclonal antibody against HER-2. The most significant adverse effect of trastuzumab is cardiotoxicity, which has become an important factor in limiting the safe use of the drug. Unfortunately, the mechanism causing this cardiotoxicity is still not completely understood, and the use of preventive interventions remains controversial. This article focuses on trastuzumab-induced cardiotoxicity, reviewing the clinical application, potential cardiotoxicity, mechanism and discussing the potential interventions through summarizing related researches over the past tens of years.

In Vivo and In Vitro Cardioprotective Effect of Gossypin Against Isoproterenol-Induced Myocardial Infarction Injury

The aim of the study was to examine the protective effects and possible mechanism of gossypin against isoproterenol (ISO)-mediated myocardial damage in vivo and H9c2 cell damage in vitro. H9c2 cells were categorized into five groups. Viability was evaluated with MTT and LDH release in H9c2 cells. Apoptotic parameter analysis was performed with cytochrome c (Cyt-c), caspase-3 (CASP-3), and BCL2/Bax mRNA expression levels. In vivo, gossypin was administered orally to mice at doses of 5, 10, and 20 mg/kg for 7 days. ISO groups were injected with isoproterenol (150 mg/kg) subcutaneously (on 8th and 9th) for 2 days. Afterward, lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB) levels and Troponin-I (Tn-I) amount from their serum, oxidative stress parameters superoxide dismutase (SOD) activity, glutathione (GSH) and malondialdehyde (MDA) levels, and tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1 β), and NF-kB mRNA expression levels with inflammatory markers from heart tissue were evaluated. In addition, IL-1B, BCL-2, and cas-3 immunohistochemical staining was performed from heart tissue and TNF-a level was measured by ELISA method. Administration of Gossypin protected the cells by dose-dependent, eliminating the reduced cell viability and increased LDH release of ISO in H9c2 cells. In mice serum analyses, increased LDH, CK-MB levels, and Tn-I levels were normalized by gossypin. ISO administration in heart tissue is regulated by gossypin with increased SOD activity, GSH amount, TNF-α, IL-6, IL-1β, and NF-kB mRNA expression levels and decreased MDA amount. Overall, the present results demonstrated that gossypin has a potential cardioprotective treatment for ischemic heart disease on in vivo and in vitro.

Insight into the Protective Effect of Salidroside against H2O2-Induced Injury in H9C2 Cells

Salidroside is the important active ingredient of Rhodiola species, which shows a wide range of pharmacological activities such as antioxidative stress, anti-inflammation, and antiliver fibrosis. In this paper, we aimed to study the protective effect and mechanism of salidroside against H2O2-induced oxidative damage in H9C2 cells by determining cell proliferation rate, intracellular reactive oxygen species (ROS) level, antioxidant enzyme activities, and the expression of apoptosis-related proteins. The results showed that salidroside significantly alleviated cell growth inhibition induced by H2O2 treatment in H9C2 cells, decreased the levels of intracellular ROS and malondialdehyde (MDA), and increased the activity of superoxide dismutase (SOD) and catalase (CAT); meanwhile, salidroside upregulated the expression of Bcl-2 while downregulated the expression of Bax, p53, and caspase-3 in H2O2-treated H9C2 cells. Furthermore, the antiapoptotic effect of salidroside was almost eliminated by the knockdown of Bcl-2. In the further exploration, the Bcl-2 expression was decreased by the p53 overexpression and increased by p53 knockdown in H2O2-treated H9C2 cells. Consequently, salidroside could protect H9C2 cells against H2O2-induced oxidative damage, and the underlying mechanism may be related to scavenging intracellular ROS, increasing the activities of intracellular antioxidant enzymes and inhibiting the expression of apoptosis-related proteins.

Traditional Chinese medicine as a therapeutic option for cardiac fibrosis: Pharmacology and mechanisms

Cardiovascular diseases are one of the leading causes of death worldwide and cardiac fibrosis is a common pathological process for cardiac remodeling in cardiovascular diseases. Cardiac fibrosis not only accelerates the deterioration progress of diseases but also becomes a pivotal contributor for futile treatment in clinical cardiovascular trials. Although cardiac fibrosis is common and prevalent, effective medicines to provide sufficient clinical intervention for cardiac fibrosis are still unavailable. Traditional Chinese medicine (TCM) is the natural essence experienced boiling, fry, and other processing methods, including active ingredients, extracts, and herbal formulas, which have been applied to treat human diseases for a long history. Recently, research has increasingly focused on the great potential of TCM for the prevention and treatment of cardiac fibrosis. Here, we aim to clarify the identified pro-fibrotic mechanisms and intensively summarize the application of TCM in improving cardiac fibrosis by working on these mechanisms. Through comprehensively analyzing, TCM mainly regulates the following pathways during ameliorating cardiac fibrosis: attenuation of inflammation and oxidative stress, inhibition of cardiac fibroblasts activation, reduction of extracellular matrix accumulation, modulation of the renin-angiotensin-aldosterone system, modulation of autophagy, regulation of metabolic-dependent mechanisms, and targeting microRNAs. We also discussed the deficiencies and the development direction of anti-fibrotic therapies on cardiac fibrosis. The data reviewed here demonstrates that TCM shows a robust effect on alleviating cardiac fibrosis, which provides us a rich source of new drugs or drug candidates. Besides, we also hope this review may give some enlightenment for treating cardiac fibrosis in clinical practice.

Current Updates on Potential Role of Flavonoids in Hypoxia/Reoxygenation Cardiac Injury Model

Clinically, timely reperfusion strategies to re-establish oxygenated blood flow in ischemic heart diseases seem to salvage viable myocardium effectively. Despite the remarkable improvement in cardiac function, reperfusion therapy could paradoxically trigger hypoxic cellular injury and dysfunction. Experimental laboratory models have been developed over the years to explain better the pathophysiology of cardiac ischemia-reperfusion injury, including the in vitro hypoxia-reoxygenation cardiac injury model. Furthermore, the use of nutritional myocardial conditioning techniques have been successful. The cardioprotective potential of flavonoids have been greatly linked to its anti-oxidant, anti-apoptotic and anti-inflammatory properties. While several studies have reviewed the cardioprotective properties of flavonoids, there is a scarce evidence of their function in the hypoxia-reoxygenation injury cell culture model. Hence, the aim of this review was to lay out and summarize our current understanding of flavonoids' function in mitigating hypoxia-reoxygenation cardiac injury based on evidence from the last five years. We also discussed the possible mechanisms of flavonoids in modulating the cardioprotective effects as such information would provide invaluable insight on future therapeutic application of flavonoids.

A review on herbal Nrf2 activators with preclinical evidence in cardiovascular diseases

Cardiovascular diseases (CVDs) are an ever-growing problem and are the most common cause of death worldwide. The uncontrolled production of reactive oxygen species (ROS) and the activation of ROS associated with various cell signaling pathways with oxidative cellular damage are the most common pathological conditions connected with CVDs including endothelial dysfunction, hypercontractility of vascular smooth muscle, cardiac hypertrophy and heart failure. The nuclear factor E2-related factor 2 (Nrf2) is a basic leucine zipper redox transcription factor, together with its negative regulator, kelch-like ECH-associated protein 1 (Keap1), which serves as a key regulator of cellular defense mechanisms to combat oxidative stress and associated diseases. Multiple lines of evidence described here support the cardiac protective property of Nrf2 in various experimental models of cardiac related disease conditions. In this review, we emphasized the molecular mechanisms of Nrf2 and described the detailed outline of current findings on the therapeutic possibilities of the Nrf2 activators specifically from herbal origin in various CVDs. Based on evidence from various preclinical experimental models, we have highlighted the activation of Nrf2 pathway as a budding therapeutic option for the prevention and treatment of CVDs, which needs further investigation and validation in the clinical settings.

Important Flavonoids and Their Role as a Therapeutic Agent

Flavonoids are phytochemical compounds present in many plants, fruits, vegetables, and leaves, with potential applications in medicinal chemistry. Flavonoids possess a number of medicinal benefits, including anticancer, antioxidant, anti-inflammatory, and antiviral properties. They also have neuroprotective and cardio-protective effects. These biological activities depend upon the type of flavonoid, its (possible) mode of action, and its bioavailability. These cost-effective medicinal components have significant biological activities, and their effectiveness has been proved for a variety of diseases. The most recent work is focused on their isolation, synthesis of their analogs, and their effects on human health using a variety of techniques and animal models. Thousands of flavonoids have been successfully isolated, and this number increases steadily. We have therefore made an effort to summarize the isolated flavonoids with useful activities in order to gain a better understanding of their effects on human health.

Clinopodium tomentosum (Kunth) Govaerts Leaf Extract Influences in vitro Cell Proliferation and Angiogenesis on Primary Cultures of Porcine Aortic Endothelial Cells

Clinopodium tomentosum (Kunth) Govaerts is an endemic species in Ecuador, where it is used as an anti-inflammatory plant to treat respiratory and digestive affections. In this work, effects of a Clinopodium tomentosum ethanolic extract (CTEE), prepared from aerial parts of the plant, were investigated on vascular endothelium functions. In particularly, angiogenesis activity was evaluated, using primary cultures of porcine aortic endothelial cells (pAECs). Cells were cultured for 24 h in the presence of CTEE different concentrations (10, 25, 50, and 100 μg/ml); no viability alterations were found in the 10-50 μg/ml range, while a slight, but significant, proliferative effect was observed at the highest dose. In addition, treatment with CTEE was able to rescue LPS-induced injury in terms of cell viability. The CTEE ability to affect angiogenesis was evaluated by scratch test analysis and by an in vitro capillary-like network assay. Treatment with 25-50 μg/ml of extract caused a significant increase in pAEC's migration and tube formation capabilities compared to untreated cells, as results from the increased master junctions' number. On the other hand, CTEE at 100 μg/ml did not induce the same effects. Quantitative PCR data demonstrated that FLK-1 mRNA expression significantly increased at a CTEE dose of 25 μg/ml. The CTEE phytochemical composition was assessed through HPLC-DAD; rosmarinic acid among phenolic acids and hesperidin among flavonoids were found as major phenolic components. Total phenolic content and total flavonoid content assays showed that flavonoids are the most abundant class of polyphenols. The CTEE antioxidant activity was also showed by means of the DPPH and ORAC assays. Results indicate that CTEE possesses an angiogenic capacity in a dose-dependent manner; this represents an initial step in elucidating the mechanism of the therapeutic use of the plant.

Role of Nrf2 and Its Activators in Cardiocerebral Vascular Disease

Cardiocerebral vascular disease (CCVD) is a common disease with high morbidity, disability, and mortality. Oxidative stress (OS) is closely related to the progression of CCVD. Abnormal redox regulation leads to OS and overproduction of reactive oxygen species (ROS), which can cause biomolecular and cellular damage. The Nrf2/antioxidant response element (ARE) signaling pathway is one of the most important defense systems against exogenous and endogenous OS injury, and Nrf2 is regarded as a vital pharmacological target. The complexity of the CCVD pathological process and the current difficulties in conducting clinical trials have hindered the development of therapeutic drugs. Furthermore, little is known about the role of the Nrf2/ARE signaling pathway in CCVD. Clarifying the role of the Nrf2/ARE signaling pathway in CCVD can provide new ideas for drug design. This review details the recent advancements in the regulation of the Nrf2/ARE system and its role and activators in common CCVD development.

Protective effect of Clinopodium chinense (Benth.) O. Kuntze against abnormal uterine bleeding in female rats

OBJECTIVES

To investigated the metrorrhagia volume-reduction activity, anti-inflammatory activity and repair-promoting activity of Clinopodium chinense (Benth.) O. Kuntze.

METHODS

An abnormal uterine bleeding (AUB) model was induced via oral administration of mifepristone and misoprostol to pregnant rats, which were treated with the total extract of C. chinense (TEC). After 7 days, the metrorrhagia volume was measured, the levels of TXB2, 6-keto-PGF1α, IL-6 and TNF-α were measured by ELISA, the pathological changes and micro vessel density (MVD) of the endometrium were evaluated using HE and immunofluorescence staining, and the expression of VEGF, MMP-2/9 and TGF-β were assessed by Western blotting. Preliminary phytochemicals were screened and identified by UPLC-Q-TOF-MS.

RESULTS

Eleven compounds in C. chinense were identified via comparison to standard substances. The results of animal experiment showed TEC could reduce metrorrhagia volume, alleviate pathological injury and increase MVD to promote recovery of the endometrium; TEC could also increase the levels of TXB2 and the expression of VEGF, TGF-β, decrease the levels of IL-6, TNF-α and the expression of MMP-2/9.

CONCLUSIONS

TEC showed beneficial effects on treating AUB by reducing metrorrhagia volume, inhibiting the inflammatory response and promoting the repair of the endometrium. Additionally, TEC also showed great haemostatic potential in AUB.

Phikud Navakot Modulates the Level of Pro-Inflammatory Mediators and the Protein Expression of SOD1 and 2 and the Nrf2/HO-1 Signaling Pathway in Rats with Acute Myocardial Infarction

Phikud Navakot (PN) is nine major herbs in a famous traditional Thai recipe namely “Yahom Navakot” used to treat cardiovascular disorders. This study investigated the cardioprotective effects of PN formula on isoproterenol-induced myocardial infarction (IMI) in Sprague-Dawley rats. Forty-five rats were randomly divided into nine groups (n = 5 per group): the control, the IMI, the IMI + propranolol, the control or the IMI + PN formula (PN ethanolic extract at doses of 64, 127, or 255 mg/kg) by oroesophageal gavage for 28 days. The ST segment and serum troponin T levels were significantly increased in IMI rats. PN did not eliminate tissue necrosis, infiltration of inflammatory cells, or interstitial edema in IMI rats. All doses of PN decreased (p < 0.001) serum TNF-α and IL-6 levels. PN (127 and 255 mg/kg) up-regulated (p < 0.05) heme oxygenase (HO)-1 expression, whereas PN (255 mg/kg) significantly increased superoxide dismutase (SOD) 1 and 2 expression, compared with IMI rats. Nuclear factor erythroid 2-related factor 2 (Nrf2) and HO-1 expression significantly increased in IMI rats and IMI rats that received PN. PN formula possesses potential anti-inflammatory and antioxidant properties by modulating the levels of TNF-α, IL-6 and antioxidant enzymes. Our study reveals a novel cardioprotective effect of PN in IMI rats through the Nrf2/HO-1 signaling.

Effect of digestion on the phenolic content and antioxidant activity of celery leaf and the antioxidant mechanism via Nrf2/HO-1 signaling pathways against Dexamethasone

The effect of digestion on the phenolic compounds and antioxidant activity of celery leaf were performed. In this work, 13 phenolic chemicals were discriminated by HPLC-MS, and content of phenolic and the antioxidant capacity were evaluated after digestion in vitro. After digestion, the content of phenols and flavonoids were increased by about 3-6-folds correlated with the average antioxidant activity (p < 0.05). It was found that the extraction of celery leaf (ET) decreased lipid peroxidation (MDA) and reactive oxygen species (ROS) level, and elevated the antioxidant activities of the liver, spleen, and thymus in Dexamethasone (Dex)-treated KM mice. Furthermore, ET increased the protein transcription of NF-E2-related factor 2 (Nrf2), hemeoxygenase-1 (HO-1) and glutathione s-transferase (GST) to against oxidation. These results suggested that ET can protect animals through the Nrf2/HO-1 signaling pathway from oxidative damage included by Dex. PRACTICAL APPLICATIONS: Celery is a daily edible vegetable with more pharmacological research focused on dietary fiber, yet fewer studies on the biological activity of small molecules, especially that in leaves. This study shows that the phenolic compounds from celery leaf have a distinct enhancement of oxidation after digestion in vitro, and the celery leaf reduces oxidative stress induced by Dex via Nrf2/HO-1 signaling pathway, indicating celery leaf or other food rich in phenolic compounds can be good source of functional food to fully use to promote the economic value. Moreover, it also provides theoretical information of celery leaf on digestion, which insinuates that food or Chinese medicine containing flavonoids, such as glycoside of apigenin or luteolin, have the similar digestion pattern, providing theoretical basis for later metabolism. Therefore, the absorption and metabolism of ET or flavonoids after digestion in body and the upstream signaling pathway activating Nrf2/HO-1, like PI3K or JNK phosphorylation, or downstream signaling pathway need further research.

Chrysanthemum extract attenuates hepatotoxicity via inhibiting oxidative stress in vivo and in vitro

Background

‘Bianliang ziyu’, a famous chrysanthemum variety commonly planted in Kaifeng, China, is often consumed by local residents. However, the hepatoprotective effects of Bianliang ziyu and their underlying mechanisms are not clear.

Objective

In this study, we investigated the hepatoprotective and antioxidative effects of Bianliang ziyu extract (BZE) on liver injury and explored its molecular mechanisms.

Design

Sprague-Dawley rats were administered BZE by intragastric administration for 8–9 days, and then alcohol or carbon tetrachloride (CCl₄) was administered by gavage to induce acute liver injury. The activities of serum alanine aminotransferase, aspartate aminotransferase, superoxide dismutase, and malondialdehyde in the rats were measured, and the liver of each rat was examined for histopathological changes. In vitro, HL-7702 cells were pretreated with BZE for 24 h and then exposed to 30 mmol•L⁻¹ acetaminophen (APAP) for 12 h. The survival rate of the cells and the alanine aminotransferase and aspartate aminotransferase activities were determined. Then, we investigated the effects of BZE on oxidative stress, apoptosis, and the activation of nuclear factor erythroid-2-related factor 2 (Nrf2) signaling in HL-7702 cells induced by APAP.

Results

The results showed that BZE prevented alcohol-, CCl₄-, and APAP-induced liver injury and suppressed hepatic oxidative stress in vitro and in vivo. BZE was also observed to significantly inhibit the reduction of mitochondrial membrane potential and regulate the expression of Bcl-2, Bax and Caspase-3 in APAP-induced HL-7702 cells. In addition, BZE significantly promoted nuclear translocation and the expression of Nrf2 as well as its downstream gene hemeoxygenase-1 (HO-1) in vitro. Furthermore, the findings showed that Nrf2 siRNA reversed the effects of BZE on cell survival and apoptosis-related protein expression in APAP-induced HL-7702 cells.

Conclusions

BZE plays an important role in preventing hepatotoxicity by inhibiting oxidative stress and apoptosis through activation of Nrf2 signaling. BZE could be developed as an effective functional food for protecting the liver.

Antioxidative and Cardioprotective Effects of Schisandra chinensis Bee Pollen Extract on Isoprenaline-Induced Myocardial Infarction in Rats

Oxidative stress plays an important role in the pathogenesis of myocardial infarction (MI). Schisandra chinensis bee pollen extract (SCBPE) possesses powerful antioxidant capacity. This study aimed to further explore the antioxidative and cardioprotective effects of SCBPE on acute MI induced by isoprenaline (ISO) in rats. The rats were intragastrically administrated with SCBPE (600, 1200, or 1800 mg/kg/day) and Compound Danshen dropping pills (270 mg/kg/day) for 30 days, then subcutaneously injected with ISO (65 mg/kg/day) on the 29th and 30th day. Compared with the model group, pretreatment with middle and high doses of SCBPE significantly reduced serum aspartate transaminase, lactate dehydrogenase, and creatine kinase activities and increased myocardial superoxide dismutase, glutathione peroxidase, and catalase activities. The histopathologic aspects showed that pathological heart change was found in the model group and reduced to varying degrees in the SCBPE groups. Moreover, the protein expression of nuclear factor-erythroid 2-related factor 2 (Nrf-2), heme oxygenase-1 (HO-1), and Bcl2 in the heart increased in the SCBPE groups, while that of Bax decreased compared to the model group. Besides this, uridine was isolated from S. chinensis bee pollen for the first time. This study could provide a scientific basis for using Schisandra chinensis bee pollen as a functional food for the prevention of MI.

Astragaloside IV Regulates the PI3K/Akt/HO-1 Signaling Pathway and Inhibits H9c2 Cardiomyocyte Injury Induced by Hypoxia-Reoxygenation

Astragaloside IV (AS-IV) is one of the main pharmacologically active compounds found in Astragalus membranaceus. AS-IV has protective effects against ischemia-reperfusion injury (IRI), but its mechanism of action has not yet been determined. This study aims to investigate the effect of AS-IV on IRI and its effect on the phosphadylinositol 3-kinase (PI3K)/Akt/heme oxygenase (HO-1) signaling pathway through in vitro experiments. Firstly, a cell culture model of myocardiocyte hypoxia-reoxygenation (H/R) injury was replicated. After AS-IV treatment, cell viability, reactive oxygen species (ROS) levels, as well as the content or activity of the cellular factors lactate dehydrogenase (LDH), superoxide dismutase (SOD), malondialdehyde (MDA), interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), were measured to evaluate the effect of treatment with AS-IV. The effect of AS-IV on HO-1 protein expression and nuclear factor E2-related factor 2 (Nrf2) and Bach1 protein expression was determined by Western blotting. Finally, a reversal of the effect of AS-IV treatment was observed following co-incubation with a PI3K inhibitor. Our results show that AS-IV has good protective effect on H/R injury and has anti-oxidative stress and anti-inflammatory effects. It can regulate the expression of Nrf2 and Bach1 proteins in the nucleus and promote the expression of HO-1 protein, while a PI3K inhibitor can partially reverse the above effects. This study suggests that the PI3K/Akt/HO-1 signaling pathway may be a key signaling pathway for the anti-IRI effect of AS-IV.

Trichosanthis Pericarpium Aqueous Extract Protects H9c2 Cardiomyocytes from Hypoxia/Reoxygenation Injury by Regulating PI3K/Akt/NO Pathway

Trichosanthis Pericarpium (TP) is a traditional Chinese medicine for treating cardiovascular diseases. In this study, we investigated the effects of TP aqueous extract (TPAE) on hypoxia/reoxygenation (H/R) induced injury in H9c2 cardiomyocytes and explored the underlying mechanisms. H9c2 cells were cultured under the hypoxia condition induced by sodium hydrosulfite for 30 min and reoxygenated for 4 h. Cell viability was measured by MTT assay. The amounts of LDH, NO, eNOS, and iNOS were tested by ELISA kits. Apoptotic rate was detected by Annexin V-FITC/PI staining. QRT-PCR was performed to analyze the relative mRNA expression of Akt, Bcl-2, Bax, eNOS, and iNOS. Western blotting was used to detect the expression of key members in the PI3K/Akt pathway. Results showed that the pretreatment of TPAE remarkably enhanced cell viability and decreased apoptosis induced by H/R. Moreover, TPAE decreased the release of LDH and expression of iNOS. In addition, TPAE increased NO production and Bcl-2/Bax ratio. Furthermore, the mRNA and protein expression of p-Akt and eNOS were activated by TPAE pretreatment. On the contrary, a specific inhibitor of PI3K, LY294002 not only inhibited TPAE-induced p-Akt/eNOS upregulation but alleviated its anti-apoptotic effects. In conclusion, results indicated that TPAE protected against H/R injury in cardiomyocytes, which consequently activated the PI3K/Akt/NO signaling pathway.

Two new flavonoid-triterpene saponin meroterpenoids from Clinopodium chinense and their protective effects against anoxia/reoxygenation-induced apoptosis in H9c2 cells

Two new flavonoid-triterpene saponin meroterpenoids, clinoposides G (1) and H (2) were isolated from the aerial parts of Clinopodium chinense (Benth.) O. Kuntze. Their structures were elucidated through spectroscopic and electronic circular dichroism (ECD) analyses. Compounds 1 and 2 were evaluated for their protective effects against anoxia/reoxygenation(A/R)-induced injury in H9c2 cells. A/R treatment severely injured the H9c2 cells, which was accompanied by apoptosis. Both 1 and 2 pretreatment significantly inhibited cell injury and apoptosis, improved mitochondrial membrane potential, increased activities of antioxidant enzymes, and reduced the levels of the inflammatory cytokines. In addition, the presence of 1 and 2 significantly decreased the protein level of p65 and increased the level of Nrf2 in cell nucleus. Unique chemical structure and good biological activity of 1 and 2 elucidated the potential of meroterpenoids as a promising reagent for treating heart disease.

Reactive Oxygen Species, Superoxide Dimutases, and PTEN-p53-AKT-MDM2 Signaling Loop Network in Mesenchymal Stem/Stromal Cells Regulation

Mesenchymal stromal/stem cells (MSCs) are multipotent cells that can differentiate to various specialized cells, which have the potential capacity to differentiate properly and accelerate recovery in damaged sites of the body. This stem cell technology has become the fundamental element in regenerative medicine. As reactive oxygen species (ROS) have been reported to adversely influence stem cell properties, it is imperative to attenuate the extent of ROS to the promising protective approach with MSCs’ regenerative therapy. Oxidative stress also affects the culture expansion and longevity of MSCs. Therefore, there is great need to identify a method to prevent oxidative stress and replicative senescence in MSCs. Phosphatase and tensin homologue deleted on chromosome 10/Protein kinase B, PKB (PTEN/AKT) and the tumor suppressor p53 pathway have been proven to play a pivotal role in regulating cell apoptosis by regulating the oxidative stress and/or ROS quenching. In this review, we summarize the current research and our view of how PTEN/AKT and p53 with their partners transduce signals downstream, and what the implications are for MSCs’ biology.