Orientin Reduces Myocardial Infarction Size via eNOS/NO Signaling and Thus Mitigates Adverse Cardiac Remodeling

Meteorin‑like/meteorin‑β protects against cardiac dysfunction after myocardial infarction in mice by inhibiting autophagy

Meteorin-β (Metrnβ) is a protein that is secreted by skeletal muscle and adipose tissue, and participates in cardiovascular diseases. However, its role in myocardial infarction (MI) has not been fully elucidated to date. The aim of the present study was to investigate the role and underlying mechanism of Metrnβ in MI. In the present study, mice were subjected to left coronary ligation to induce a MI model before being injected with adeno-associated virus 9 (AAV9)-Metrnβ to overexpress Metrnβ. Mice were subjected to echocardiography and pressure-volume measurements 2 weeks after ligation. Cardiac injury was measured from the levels of cardiac troponin T and pro-inflammatory factors, which were detected using ELISA kits. Cardiac remodelling was determined from the cross-sectional areas detected using H&E and wheat germ agglutinin staining as well as from the transcriptional levels of hypertrophic and fibrosis markers detected using reverse transcription-quantitative PCR. Cardiac function was detected using echocardiography and pressure-volume measurements. In addition, H9c2 cardiomyocytes were transfected with Ad-Metrnβ to overexpress Metrnβ, before being exposed to hypoxia to induce ischaemic injury. Apoptosis was determined using TUNEL staining and caspase 3 activity. Cell inflammation was detected using ELISA assays for pro-inflammatory factors. Autophagy was detected using LC3 staining and assessing the protein level of LC3II using western blotting. H9c2 cells were also treated with rapamycin to induce autophagy. It was revealed that Metrnβ expression was reduced in both mouse serum and heart tissue 2 weeks post-MI. Metrnβ overexpression using AAV9-Metrnβ delivery reduced the mortality rate, decreased the infarction size and reduced the extent of myocardial injury 2 weeks post-MI. Furthermore, Metrnβ overexpression inhibited cardiac hypertrophy, fibrosis and inflammation post-MI. In ischaemic H9c2 cells, Metrnβ overexpression using adenovirus also reduced cell injury, cell death and inflammatory response. Metrnβ overexpression suppressed MI-induced autophagy in vitro. Following autophagy activation using rapamycin in vitro, the protective effects induced by Metrnβ were reversed. Taken together, these results indicated that Metrnβ could protect against cardiac dysfunction post-MI in mice by inhibiting autophagy.

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.

Orientin alleviates ox-LDL-induced oxidative stress, inflammation and apoptosis in human vascular endothelial cells by regulating Sestrin 1 (SESN1)-mediated autophagy

Endothelial cells are a crucial component of the vessel-tissue wall and exert an important role in atherosclerosis (AS). To explore the role of Orientin in AS, human vascular endothelial cells (HUVECs) were induced by oxidized low-density lipoprotein (ox-LDL) to simulate the vascular endothelial injury during AS. Cell viability was detected by CCK-8 assay. Oxidative stress and inflammation related markers were measured using kits, RT-qPCR or western blot. Besides, cell apoptosis was assessed with TUNEL staining and cell autophagy was evaluated by LC3 immunofluorescent staining. Additionally, western blot was utilized to evaluate the expression of Sestrin 1 (SESN1) and proteins in AMPK/mTOR signaling. Afterwards, SESN1 was silenced to determine the expression of autophagy-related proteins. The further application of autophagy inhibitor 3-methyladenine (3-MA) was used to clarify the regulatory mechanism of Orientin on autophagy. Results showed that the decreased viability of HUVECs caused by ox-LDL induction was elevated by Orientin. Oxidative stress and inflammation were also attenuated after Orientin addition in HUVECs under ox-LDL condition. Moreover, Orientin suppressed apoptosis and induced autophagy of HUVECs stimulated by ox-LDL, accompanied by enhanced level of phospho (p)-AMPK and declined level of p-mTOR. Interestingly, SESN1 level was elevated by Orientin, and SESN1 depletion alleviated autophagy and reduced p-AMPK expression but enhanced p-mTOR expression. The further experiments indicated that SESN1 silencing or 3-MA addition reversed the inhibitory effects of Orientin on the oxidative stress, inflammation and apoptosis of HUVECs. Collectively, Orientin could induce autophagy by activating SESN1 expression, thereby regulating AMPK/mTOR signaling in ox-LDL-induced HUVECs.

Natural products as the calcium channel blockers for the treatment of arrhythmia: Advance and prospect

Arrhythmia is one of the commonly heart diseases with observed abnormal heart-beat rhythm that caused by the obstacles of cardiac activity and conduction. The arrhythmic pathogenesis is complex and capricious and related with other cardiovascular diseases that may lead to heart failure and sudden death. In particular, calcium overload is recognized as the main reason causing arrhythmia through inducing apoptosis in cardiomyocytes. Moreover, calcium channel blockers have been widely used as the routine drugs for the treatment of arrhythmia, but the different arrhythmic complications and adverse effects limit their further applications and demand new drug discovery. Natural products have always been the rich minerals for the development of new drugs that could be employed as the versatile player for the discovery of safe and effective anti-arrhythmia drugs with new mechanisms. In this review, we summarized natural products with the activity against calcium signaling and the relevant mechanism of actions. We are expected to provide an inspiration for the pharmaceutical chemists to develop more potent calcium channel blockers for the treatment of arrhythmia.

Micro-Executor of Natural Products in Metabolic Diseases

Obesity, diabetes, and cardiovascular diseases are the major chronic metabolic diseases that threaten human health. In order to combat these epidemics, there remains a desperate need for effective, safe, and easily available therapeutic strategies. Recently, the development of natural product research has provided new methods and options for these diseases. Numerous studies have demonstrated that microRNAs (miRNAs) are key regulators of metabolic diseases, and natural products can improve lipid and glucose metabolism disorders and cardiovascular diseases by regulating the expression of miRNAs. In this review, we present the recent advances involving the associations between miRNAs and natural products and the current evidence showing the positive effects of miRNAs for natural product treatment in metabolic diseases. We also encourage further research to address the relationship between miRNAs and natural products under physiological and pathological conditions, thus leading to stronger support for drug development from natural products in the future.

The Relationship between the Serum NLRP1 Level and Coronary Lesions in Patients with Coronary Artery Disease

Background

The pathogenesis of coronary artery disease is complex, and inflammation is one of the regulatory factors. The nucleotide-binding oligomerization domain (NOD)-like receptor protein 1 (NLRP1) plays an important role in the cellular inflammatory response, cell apoptosis, cell death, and autoimmune diseases. Whether the level of NLRP1 is related to the severity of coronary artery stenosis in patients with coronary artery disease (CAD) has not been reported.

Objective

To test the serum level of NLRP1 in unstable angina (UA) patients and investigate the effect of NLRP1 on coronary stenosis severity of the coronary artery disease (CAD).

Methods

307 patients hospitalized in the Department of Cardiology of the Affiliated Hospital of Xuzhou Medical University for coronary angiography from January 1, 2021, to December 31, 2022 were included. We detect the level of NLRP1 in the serum of the included patients. Patients were divided into UA group and control group according to coronary angiography results and other clinical data. We use logistic regression to screen the influencing factors of UA. Then, subgroups were divided according to the Gensini score and the number of coronary artery lesions, and the difference of serum NLRP1 level between the groups was compared. Spearman correlation analysis was used to explore the correlation between the serum NLRP1 level and Gensini score. We analyze the diagnostic value of NLRP1 for UA by drawing ROC curve.

Results

The median level of serum NLRP1 in patients with UA (n = 257) was 49.71 pg/ml, IQR 30.15, 80.21, and that in patients without UA (n = 50) was 24.75 pg/ml, IQR 13.49, 41.95. Serum NLRP1 levels were significantly different among different subgroups. The patient's Gensini score was correlated with the patient's serum NLRP1 level.

Conclusion

The serum NLRP1 level is increased in patients with UA, which is increased with the increasing severity of coronary lesions.

Pharmacological mechanism of natural drugs and their active ingredients in the treatment of arrhythmia via calcium channel regulation

Arrhythmia is characterized by abnormal heartbeat rhythms and frequencies caused by heart pacing and conduction dysfunction. Arrhythmia is the leading cause of death in patients with cardiovascular disease, with high morbidity and mortality rates, posing a serious risk to human health. Natural drugs and their active ingredients, such as matrine(MAT), tetrandrine(TET), dehydroevodiamine, tanshinone IIA, and ginsenosides, have been widely used for the treatment of atrial fibrillation, ventricular ectopic beats, sick sinus syndrome, and other arrhythmia-like diseases owing to their unique advantages. This review summarizes the mechanism of action of natural drugs and their active ingredients in the treatment of arrhythmia via the regulation of Ca²⁺, such as alkaloids, quinones, saponins, terpenoids, flavonoids, polyphenols, and lignan compounds, to provide ideas for the innovative development of natural drugs with potential antiarrhythmic efficacy.

Orientin Prolongs the Longevity of Caenorhabditis elegans and Postpones the Development of Neurodegenerative Diseases via Nutrition Sensing and Cellular Protective Pathways

Age is the major risk factor for most of the deadliest diseases. Developing small molecule drugs with antiaging effects could improve the health of aged people and retard the onset and progress of aging-associated disorders. Bioactive secondary metabolites from medicinal plants are the main source for development of medication. Orientin is a water-soluble flavonoid monomer compound widely found in many medicinal plants. Orientin inhibits fat production, antioxidation, and anti-inflammatory activities. In this study, we explored whether orientin could affect the aging of C. elegans. We found that orientin improved heat, oxidative, and pathogenic stress resistances through activating stress responses, including HSF-1-mediated heat shock response, SKN-1-mediated xenobiotic and oxidation response, mitochondria unfolded responses, endoplasmic unfolded protein response, and increased autophagy activity. Orientin also could activate key regulators of the nutrient sensing pathway, including AMPK and insulin downstream transcription factor FOXO/DAF-16 to further improve the cellular health status. The above effects of orientin reduced the accumulation of toxic proteins (α-synuclein, β-amyloid, and poly-Q) and delayed the onset of neurodegenerative disorders in AD, PD, and HD models of C. elegans and finally increased the longevity and health span of C. elegans. Our results suggest that orientin has promising antiaging effects and could be a potential natural source for developing novel therapeutic drugs for aging and its related diseases.

Cathelicidin-WA ameliorates diabetic cardiomyopathy by inhibiting the NLRP3 inflammasome

Cathelicidin-WA (CWA) is a novel cathelicidin peptide isolated from snakes that has been suggested to exert anti-inflammatory effects. The aim of our study was to investigate whether cathelicidin-WA (CWA) could protect the heart from diabetic cardiomyopathy (DCM). Streptozotocin (STZ) injection was used to establish a mouse model of DCM. CWA peptide (2 mg/kg or 8 mg/kg) was continuously administered to the mice from 10 weeks to 16 weeks after STZ injection. The mice in the DCM group exhibited cardiac dysfunction, while 8 mg/kg CWA ameliorated this cardiac dysfunction. Cardiac fibrosis, inflammation, and oxidative stress as well as cardiomyocyte apoptosis in the DCM mice were decreased by treatment with 8 mg/kg CWA. We isolated neonatal rat cardiomyocytes and stimulated the cells with high glucose to establish an in vitro model of myocyte cell injury. Consistently, CWA inhibited high glucose-induced cell death, inflammation and oxidative stress in the myocytes. Moreover, CWA reduced the formation of the NLR family pyrin domain-containing 3 (NRLP3) inflammasome by regulating thioredoxin-interacting protein expression and p65 activation. NLRP3 overexpression inhibited the beneficial effects of CWA on the heart during DCM and on high glucose-induced myocyte injury. In summary, CWA attenuates cardiac injury and preserves cardiac function during DCM by targeting the NLRP3 pathway.Abbreviations: AAV9: Adeno associated virus; AGE: Advanced Glycation End products; CWA: Cathelicidin-WA; DCM: diabetic cardiomyopathy; Gpx: glutathione peroxidase; HG: high glucose; IL: Interleukin; NLR: Family Pyrin Domain Containing 3 (NRLP3); TXNIP: Thioredoxin interacting protein; LVEF: left ventricular ejection fraction; MDA: Malondialdehyde; MnSOD: manganese superoxide dismutase; NADPH: Nicotinamide adenine dinucleotide phosphate; NAC: N-acetyl-cysteine; NRCMs: Neonatal rat cardiomyocytes; ROS: reactive oxygen species; STZ: Streptozotocin; TNFa: tumor necrosis factor a.

Nitric Oxide Alleviated High Salt-Induced Cardiomyocyte Apoptosis and Autophagy Independent of Blood Pressure in Rats

The present study aimed to explore whether high-salt diet (HSD) could cause cardiac damage independent of blood pressure, and whether nitric oxide (NO) could alleviate high-salt-induced cardiomyocyte apoptosis and autophagy in rats. The rats received 8% HSD in vivo. H9C2 cells or primary neonatal rat cardiomyocytes (NRCM) were treated with sodium chloride (NaCl) in vitro. The levels of cleaved-caspase 3/caspase 3, cleaved-caspase 8/caspase 8, Bax/Bcl2, LC3 II/LC3 I, Beclin-1 and autophagy related 7 (ATG7) were increased in the heart of HSD rats with hypertension (HTN), and in hypertension-prone (HP) and hypertension-resistant (HR) rats. Middle and high doses (50 and 100 mM) of NaCl increased the level of cleaved-caspase 3/caspase 3, cleaved-caspase 8/caspase 8, Bax/Bcl2, LC3 II/LC3 I, Beclin-1, and ATG7 in H9C2 cells and NRCM. The endothelial NO synthase (eNOS) level was increased, but p-eNOS level was reduced in the heart of HSD rats and H9C2 cells treated with 100 mM NaCl. The level of NO was reduced in the serum and heart of HSD rats. NO donor sodium nitroprusside (SNP) reversed the increases of cleaved-caspase 3/caspase 3, cleaved-caspase 8/caspase 8, Bax/Bcl2 induced by NaCl (100 mM) in H9C2 cells and NRCM. SNP treatment attenuated the increases of cleaved-caspase 3/caspase 3, Bax/Bcl2, LC3 II/LC3 I, Beclin-1, and ATG7 in the heart, but had no effect on the blood pressure of HSD rats with HR. These results demonstrated that HSD enhanced cardiac damage independently of blood pressure. Exogenous NO supplementarity could alleviate the high salt-induced apoptosis and autophagy in cardiomyocytes.

Recent Research on Flavonoids and their Biomedical Applications

Flavonoids, commonly found in various plants, are a class of polyphenolic compounds having a basic structural unit of 2-phenylchromone. Flavonoid compounds have attracted much attention due to their wide biological applications. In order to facilitate further research on the biomedical application of flavonoids, we surveyed the literature published on the use of flavonoids in medicine during the past decade, documented the commonly found structures in natural flavonoids, and summarized their pharmacological activities as well as associated mechanisms of action against a variety of health disorders including chronic inflammation, cancer, cardiovascular complications and hypoglycemia. In this mini-review, we provide suggestions for further research on the biomedical applications of flavonoids.

Advances in the Protective Mechanism of NO, H2S, and H2 in Myocardial Ischemic Injury

Myocardial ischemic injury is among the top 10 leading causes of death from cardiovascular diseases worldwide. Myocardial ischemia is caused mainly by coronary artery occlusion or obstruction. It usually occurs when the heart is insufficiently perfused, oxygen supply to the myocardium is reduced, and energy metabolism in the myocardium is abnormal. Pathologically, myocardial ischemic injury generates a large number of inflammatory cells, thus inducing a state of oxidative stress. This sharp reduction in the number of normal cells as a result of apoptosis leads to organ and tissue damage, which can be life-threatening. Therefore, effective methods for the treatment of myocardial ischemic injury and clarification of the underlying mechanisms are urgently required. Gaseous signaling molecules, such as NO, H₂S, H₂, and combined gas donors, have gradually become a focus of research. Gaseous signaling molecules have shown anti-apoptotic, anti-oxidative and anti-inflammatory effects as potential therapeutic agents for myocardial ischemic injury in a large number of studies. In this review, we summarize and discuss the mechanism underlying the protective effect of gaseous signaling molecules on myocardial ischemic injury.

Comparative Tissue Distribution of 6 Major Polyphenolic Compounds in Normal and Myocardial Ischemia Model Rats After Oral Administration of the Polygonum orientale L. Extract

A simple, rapid, and selective ultra-performance liquid chromatography-mass spectrometry (MS)/MS method was established to investigate tissue distribution of 6 polyphenolic compounds of Polygonum orientale L. extract in normal and myocardial ischemia (MI) model rat tissues, including isoorientin, orientin, vitexin, quercitrin, astragalin, and protocatechuic acid. An Agilent Eclipse Plus C18 column was used. The mobile phase consisted of acetonitrile and water, both with 0.1% formic acid. Quantification was performed in negative ion multiple reaction monitoring mode. All the analysts had good linearity with r ≥ 0.9912. Accuracy ranged from 12.49% to −13.98% for the 6 compounds; within-day variation (precision) was ≤9.98% and interday precision was ≤11.88%. Extraction recovery of the analysts ranged from 80.55% to 99.92%; the matrix was 81.00%–98.73%. The analyst preparations were stable throughout. The 6 compounds were rapidly distributed in various tissues after oral administration, without accumulation over 12 hours. Compared with normal rats, distributions of 6 compounds in the heart, liver, spleen, lung, kidney, brain, stomach, and intestine in MI model rats were different from those in the normal group. The study provides an insight for further research of P. orientale L.

Angiotensin-(1–7) reduces doxorubicin-induced cardiac dysfunction in male and female Sprague-Dawley rats through antioxidant mechanisms

Doxorubicin (Dox) is an effective chemotherapeutic for a variety of pediatric malignancies. Unfortunately, Dox administration often results in a cumulative dose-dependent cardiotoxicity that manifests with marked oxidative stress, leading to heart failure. Adjunct therapies are needed to mitigate Dox cardiotoxicity and enhance quality of life in pediatric patients with cancer. Angiotensin-(1–7) [Ang-(1–7)] is an endogenous hormone with cardioprotective properties. This study investigated whether adjunct Ang-(1–7) attenuates cardiotoxicity resulting from exposure to Dox in male and female juvenile rats. Dox significantly reduced body mass, and the addition of Ang-(1–7) had no effect. However, adjunct Ang-(1–7) prevented Dox-mediated diastolic dysfunction, including markers of decreased passive filling as measured by reduced early diastole mitral valve flow velocity peak ( E) ( P < 0.05) and early diastole mitral valve annulus peak velocity ( e′; P < 0.001) and increased E/e′ ( P < 0.001), an echocardiographic measure of diastolic dysfunction. Since Dox treatment increases reactive oxygen species (ROS), the effect of Ang-(1–7) on oxidative by-products and enzymes that generate or reduce ROS was investigated. In hearts of male and female juvenile rats, Dox increased NADPH oxidase 4 ( P < 0.05), a major cardiovascular NADPH oxidase isozyme that generates ROS, as well as 4-hydroxynonenal ( P < 0.001) and malondialdehyde ( P < 0.001), markers of lipid peroxidation; Ang-(1–7) prevented these effects of Dox. Cotreatment with Dox and Ang-(1–7) increased the antioxidant enzymes SOD1 (male: P < 0.05; female: P < 0.01) and catalase ( P < 0.05), which likely contributed to reduced ROS. These results demonstrate that Ang-(1–7) prevents diastolic dysfunction in association with a reduction in ROS, suggesting that the heptapeptide hormone may serve as an effective adjuvant to improve Dox-induced cardiotoxicity.

NEW & NOTEWORTHY Ang-(1–7) is a clinically safe peptide hormone with cardioprotective and antineoplastic properties that could be used as an adjuvant therapy to improve cancer treatment and mitigate the long-term cardiotoxicity associated with doxorubicin in pediatric patients with cancer.

Follistatin-like 1: A dual regulator that promotes cardiomyocyte proliferation and fibrosis

Follistatin-like 1 (FSTL1) is a key factor in maintaining cardiac growth and development. It can be activated by exercise training and has a dual role in promoting cardiomyocyte proliferation and fibrosis, but its underlying mechanism is not fully understood. To elucidate the dual mechanism and target of FSTL1 regulating of cardiomyocyte proliferation and myocardial fibrosis, and the mechanism by which exercise-regulated FSTL1 improves cardiovascular disease, we explored the signal transduction pathway of FSTL1 promoting cardiomyocyte proliferation and fibrosis, and compared the effects of different modes of exercise on the dual role of FSTL1. We believe that the dual role of promoting cardiomyocyte proliferation and fibrosis may be related to the ratio of cardiomyocyte and myocardial interstitial cell proliferation, different stages of the disease, different degrees of fibrosis, immune repair process, and transforming growth factor-β activation. Compared with long-term excessive endurance exercise, moderate resistance exercise can activate cardiomyocyte proliferation pathway through FSTL1, which is one of the effective ways to prevent cardiovascular disease.

Inhibitory effects of orientin in mast cell-mediated allergic inflammation

BACKGROUND

Mast cells are immune effector cells mediating allergic inflammation by the secretion of inflammatory mediators such as histamine and pro-inflammatory cytokines. Orientin is a naturally occurring bioactive flavonoid that possesses diverse biological properties, including anti-inflammation, anti-oxidative, anti-tumor, and cardio protection. The objective of this study was to rule out the effectiveness of orientin in mast cell-mediated allergic inflammation.

METHODS

In this study, in vitro effects of orientin were evaluated in RBL-2H3, mouse bone marrow-derived mast cells, rat peritoneal mast cells, and in vivo effects were evaluated by inducing passive cutaneous anaphylaxis (PCA) in Imprinting Control Region (ICR) mice.

RESULTS

Findings show that orientin suppressed the immunoglobulin E (IgE)-mediated mast cell degranulation by reducing intracellular calcium level in a concentration-dependent manner. Orientin suppressed the secretion of pro-inflammatory cytokines in mast cells. This inhibitory effects of orientin was through inhibition of FcεRI-mediated signaling proteins. In addition, oral administration of orientin suppressed the IgE-mediated PCA reactions in a dose-dependent manner, which was evidenced by reduced Evan's blue pigmentation and ear swelling.

CONCLUSIONS

Based on these findings, we suggest that orientin might have potential to alleviate allergic reaction and mast cell-mediated allergic disease.

Orientin suppresses oxidized low-density lipoproteins induced inflammation and oxidative stress of macrophages in atherosclerosis

Atherosclerosis is a main reason for peripheral vascular disease. The present study aims to investigate the effects of macrophage foam cells which is an initial part in atherosclerosis. RAW 264.7 were treated with 80 μg/mL oxidized low-density lipoproteins (ox-LDL) to mimic atherosclerosis in vitro. Orientin, a flavonoid from plants, inhibited ox-LDL induced TNFα, IL-6, IL-1β expression increase. In addition, Orientin also can inhibit the emergence of ox-LDL-induced lipid droplets. The scavenger receptor CD 36 of ox-LDL was significantly downregulated after the treatment of orientin. Inhibition of ROS generation and increasing of eNOS expression by Orientin treatment was used to show the alteration of oxidative stress. Moreover, the expression levels of Angiopoietin-like 2 (angptl2) and NF-κB were significantly upregulated after cells induced by ox-LDL, whereas orientin significantly reversed the effects of ox-LDL. Orientin inhibited ox-LDL-induced inflammation and oxidative stress, and CD36 may be the key regulator during Orientin action.

Quinoa Secondary Metabolites and Their Biological Activities or Functions

Quinoa (Chenopodium quinoa Willd.) was known as the "golden grain" by the native Andean people in South America, and has been a source of valuable food over thousands of years. It can produce a variety of secondary metabolites with broad spectra of bioactivities. At least 193 secondary metabolites from quinoa have been identified in the past 40 years. They mainly include phenolic acids, flavonoids, terpenoids, steroids, and nitrogen-containing compounds. These metabolites exhibit many physiological functions, such as insecticidal, molluscicidal and antimicrobial activities, as well as various kinds of biological activities such as antioxidant, cytotoxic, anti-diabetic and anti-inflammatory properties. This review focuses on our knowledge of the structures, biological activities and functions of quinoa secondary metabolites. Biosynthesis, development and utilization of the secondary metabolites especially from quinoa bran were prospected.

Aspalathus linearis (Rooibos) - a functional food targeting cardiovascular disease

Increasing consumer bias toward natural products and the considerable wealth of indigenous knowledge has precipitated an upturn in market-driven research into potentially beneficial medicinal plants. In this context, Aspalathus linearis (Rooibos) has been identified to be a promising candidate which may impact cardiovascular disease (CVD), which is one of the most widely studied chronic diseases of modern times. Despite these efforts, ischemic heart disease remains the number one cause of mortality globally. Apart from genetic predisposition and other aetiological mechanisms specific to particular types of CVD, co-factors from interlinked systems contribute significantly to disease development and the severity of its clinical manifestation. The bioactivity of Rooibos is directed towards multiple therapeutic targets. Experimental data to date include antioxidant, anti-inflammatory and anti-diabetic effects, as well as modulatory effects in terms of the immune system, adrenal steroidogenesis and lipid metabolism. This review integrates relevant literature on the therapeutic potential of Rooibos in the context of CVD, which is currently the most common of non-communicable diseases. The therapeutic value of whole plant extracts versus isolated active ingredients are addressed, together with the potential for overdose or herb-drug interaction. The body of research undertaken to date clearly underlines the benefits of Rooibos as both preventative and complementary therapeutic functional food in the context of CVD.

CXCL16 is activated by p-JNK and is involved in H2O2-induced HK-2 cell injury via p-ERK signaling

Acute kidney injury (AKI) leads to an abrupt deterioration of renal function. CXC chemokine ligand 16 (CXCL16) is a CXC-soluble chemokine and a cell surface scavenger receptor that is involved in tissue injury and inflammation. It is induced in AKI patients, but the molecular mechanism remains unclear. In this study, we have worked to determine the function of CXCL16 and to investigate the involvement of ERK and JNK signaling in AKI. We used H₂O₂ and recombinant human CXCL16 protein (rh CXCL16) to treat the human renal tubular epithelial cell line, HK-2, in vitro. The present results indicate that H₂O₂ inhibits proliferation, induces apoptosis, and up-regulates expression of CXCL16 and the CXCL16 receptor, CXCR6, in HK-2 cells. Furthermore, H₂O₂-induced proliferation inhibition, apoptosis, and inflammation in HK-2 cells were ameliorated by NAC (N-acetyl cysteine, the ROS scavenger) and SP600125 (the JNK inhibitor). The expression levels of CXCL16 and CXCR6 were also positively correlated with the phosphorylation level of JNK (p-JNK). Additionally, rh CXCL16 treatment led to effects like those of H₂O₂ treatment in HK-2 cells, with symptoms being effectively improved by CXCR6 siRNA and the ERK inhibitor (PD98059). In addition, rh CXCL16-induced HK-2 cell apoptosis, inflammation, and collagen deposition were lessened by CXCR6 siRNA and PD98059 treatment. In summary, the present results have indicated that CXCL16 is involved in H₂O₂-induced HK-2 cell injury, that CXCL16 is activated by p-JNK, and that the regulatory function of CXCL16 is involved in the phosphorylation of ERK.