Involvement of AMPK and MAPK signaling during the progression of experimental autoimmune myocarditis in rats and its blockade using a novel antioxidant

Interleukin 22 and its association with neurodegenerative disease activity

It is worth noting that neuroinflammation is well recognized as a symptom of neurodegenerative diseases (NDs). The regulation of neuroinflammation becomes an attractive focus for innovative ND treatment technologies. There is evidence that IL-22 is associated with the development and progression of a wide assortment of NDs. For example, IL-22 can activate glial cells, causing them to generate pro-inflammatory cytokines and encourage lymphocyte infiltration in the brain. IL-22 mRNA is highly expressed in Alzheimer’s disease (AD) patients, and a high expression of IL-22 has also been detected in the brains of patients with other NDs. We examine the role of IL-22 in the development and treatment of NDs in this review, and we believe that IL-22 has therapeutic potential in these diseases.

Edaravone Inhibits the Production of Reactive Oxygen Species in Phagocytosis- and PKC-Stimulated Granulocytes from Multiple Sclerosis Patients Edaravone Modulate Oxidative Stress in Multiple Sclerosis

Background

Oxidative stress is associated with the pathogenesis of MS. Edaravone (EDV) has been proposed as a therapeutic resource for central nervous system diseases, and it was effective in reducing oxidative stress. However, the antioxidant mechanisms of EDV are poorly studied.

Objective

This study aimed to evaluate the effects of EDV on resting, phagocytosis, and PKC-activated granulocytes derived from MS patients and a healthy control group.

Methods

The effects of EDV on ROS production in phagocytosis (ROS production in the presence of opsonized particles) and PKC-stimulated granulocytes were evaluated in a luminol-dependent chemiluminescence method. Calphostin C was used in some experiments to compare with those of EDV.

Results

EDV inhibited ROS production in phagocytosis of opsonized particles and PKC-stimulated granulocytes from MS patients and healthy control group. In the presence of calphostin C, the inhibition of ROS production was similar to that observed with EDV.

Conclusion

These findings suggest the involvement of EDV on the ROS-PKC-NOX signaling pathways modulating oxidative stress in MS. EDV represents a promising treatment option to control oxidative innate immune response for MS.

Inhibitory Effect of Quercetin on Propionibacterium acnes-induced Skin Inflammation

Quercetin is a well-known antioxidant and a plant polyphenolic of flavonoid group found in many fruits, leaves, and vegetables. Propionibacterium acnes is a key skin pathogen involved in the progression of acne inflammation. Although quercetin has been applied to treat various inflammatory diseases, the effects of quercetin on P. acnes-induced skin inflammation have not been explored. This study investigated the effects of quercetin on P. acnes-induced inflammatory skin disease in vitro and in vivo. The results showed that quercetin suppressed the production of pro-inflammatory cytokines in P. acnes-stimulated HaCaT, THP-1 and RAW 264.7 cells. Additionally, quercetin reduced the production of TLR-2 and the phosphorylation of p38, ERK and JNK MAPKs in P. acnes-stimulated HaCaT and THP-1 cells. It also suppressed MMP-9 mRNA levels in two cell lines exposed to P. acnes in vitro. In the case of in vivo, P. acnes was intradermally injected into the ears of mice and it resulted in cutaneous erythema, swelling, and a granulomatous response. Treatment with quercetin markedly reduced ear thickness and swelling. These results suggested that quercetin can be a potential therapeutic agent against P. acnes-induced skin inflammation and may have diverse pharmaceutical and cosmetics applications.

Chitoheptaose Promotes Heart Rehabilitation in a Rat Myocarditis Model by Improving Antioxidant, Anti-Inflammatory, and Antiapoptotic Properties

Background

Myocarditis is one of the important causes of dilated cardiomyopathy, cardiac morbidity, and mortality worldwide. Chitosan oligosaccharides (COS) may have anti-inflammatory and cardioprotective effects on myocarditis. However, the exact molecular mechanism for the effects of functional COS on myocarditis remains unclear.

Methods

Anti-inflammatory activities of COS (chitobiose, chitotriose, chitotetraose, chitopentaose, chitohexaose, chitoheptaose, and chitooctaose) were measured in lipopolysaccharide- (LPS-) stimulated RAW264.7 cells. A rat model with myocarditis was established and treated with chitopentaose, chitohexaose, chitoheptaose, and chitooctaose. Serum COS were measured by using high-performance liquid chromatography (HPLC) in all rats. Myocarditis injury, the levels of reactive oxygen species (ROS), reactive nitrogen species (RNS), inflammatory factors, and apoptotic factors were also measured. Pearson's correlation coefficient test was used to explore the relationship between the levels of ROS/RNS and cardiac parameters.

Results

Among all chitosan oligosaccharides, the COS > degrees of polymerization (DP) 4 showed anti-inflammatory activities (the activity order was chitopentaose<chitohexaose<chitoheptaose<chitooctaose) by reducing the levels of interleukin- (IL-) 1β, IL-17A, and interferon- (IFN-) γ and increasing the level of IL-10. However, the serum level of chitooctaose was low whereas it showed significant therapeutic effects on myocarditis by improving cardiac parameters (left ventricular internal dimension, both end-systolic and end-diastolic, ejection fraction, and fractional shortening), inflammatory cytokines (IL-1β, IL-10, IL-17A, and IFN-γ), oxidative factors (ROS and RNS), and apoptotic factors (caspase 3, BAX, and BCL-2) when compared with chitopentaose, chitohexaose, and chitooctaose (COS DP > 4). The levels of ROS/RNS had a strong relationship with cardiac parameters.

Conclusions

Chitoheptaose plays a myriad of cardioprotective roles in the myocarditis model via its antioxidant, anti-inflammatory, and antiapoptotic activities.

Adenine decreases hypertrophic effects through interleukin-18 receptor

Cardiac hypertrophy is the main cause of heart failure. Levels of circulating interleukin-18 (IL-18) have been reported to increase in congestive heart disease and cardiac hypertrophy. Relationships among IL-18 levels, IL-18 receptor (IL-18R) expression, and cardiac hypertrophy remain unclear. IL-18 can induce cardiac hypertrophy in cardiomyoblasts. We also studied IL-18R messenger RNA (mRNA) and protein expression through quantitative-polymerase chain reaction and Western blotting. Furthermore, we treated cardiomyoblasts with adenine, gold nanoparticles (AuNPs), and inhibitors to analyze the morphology and identify signaling pathways involved in cardiac hypertrophy. Moreover, we studied the effects of IL-18R small interfering RNA (siRNA) on signaling pathways through Western blotting. The mRNA expression of IL-18R in H9c2 cardiomyoblasts, which was induced by IL-18, increased significantly after 8 h, and the protein level increased significantly after 15 h. Morphological examination of H9c2 cardiomyoblasts showed that cell volume and cell diameter decreased after adenine pretreatment. Both p38 MAPK and PI3 kinase are biomarkers in the pathway correlated with cardiac hypertrophy. After treatment with inhibitors SB203580 and LY294002, the levels of p38 MAPK and PI3 kinase, respectively, decreased along with cell size and IL-18R expression. Treatment with adenine, but not AuNPs, reduced the levels of phosphorylated p38 and PI3 kinase expression more effectively than did treatment with the respective inhibitors alone. IL-18R siRNA significantly reduced cell size but not PI3 kinase expression and phosphorylation of p38 MAPK. However, adenine treatment reduced PI3 kinase expression after treatment with IL-18R siRNA. In this study, IL-18 induced cardiomyoblast hypertrophy through IL-18R upregulation, which was found to be related to p38 MAPK and PI3 kinase signaling. Adenine, but not AuNPs, showed antihypertrophic effects possibly because of decreased levels of signaling.

Differential expression profiles and functional analysis of circular RNAs in children with fulminant myocarditis

Aim: To assess differential expression profiles of circular RNAs (circRNAs) and explore their possible functions in children with fulminant myocarditis. Materials & methods: circRNA microarray experiments were carried out for determining differential expression profiles of circRNAs in three children with fulminant myocarditis and three healthy volunteers. Functional analysis and circRNA-miRNA-mRNA interaction network building were conducted to study biological functions. Results: This work identified 2281 upregulated and 892 downregulated circRNAs. Further assessment confirmed hsa_circ_0071542 upregulation (2.5-fold) in fulminant myocarditis. Functional analysis demonstrated the differentially expressed circRNAs mainly contributed to inflammation and immunity. Conclusion: circRNAs might have substantial roles in pediatric fulminant myocarditis, and hsa_circ_0071542 could serve as a promising biomarker.

Comparative evaluation of torasemide and spironolactone on adverse cardiac remodeling in a rat model of dilated cardiomyopathy

BACKGROUND

Chronic heart failure (CHF) involves fluid retention and volume overload, leading to impaired cardiac function. In these conditions, diuretic agents are most commonly used to treat edema and thereby reducing the volume load on the failing heart. There are several other beneficial effects of diuretics apart from their action on urinary excretion.

METHODS

To identify the effects of diuretic agents on adverse cardiac remodeling in CHF, this study was carried out, where we have compared the effects of torasemide and spironolactone in a rat model of dilated cardiomyopathy induced by porcine cardiac myosin-mediated experimental autoimmune myocarditis.

RESULTS

Cardiac protein expression levels of inflammation, endoplasmic reticulum stress, and fibrosis markers were upregulated in the hearts of CHF rats, while treatment with either torasemide or spironolactone has downregulated their expression. The effect produced by spironolactone on cardiac fibrosis markers was comparably lesser than torasemide. Further, immunohistochemical analysis and histopathological studies have provided evidence to confirm the beneficial effects of these drugs on adverse cardiac remodeling in rats with CHF.

CONCLUSION

Torasemide treatment has benefits against adverse cardiac remodeling in CHF rats, which was better than the protection offered by spironolactone.

Comparative effects of torasemide and furosemide on gap junction proteins and cardiac fibrosis in a rat model of dilated cardiomyopathy

Cardiac fibrosis is the major hallmark of adverse cardiac remodeling in chronic heart failure (CHF) and its therapeutic targeting might help against cardiac dysfunction during chronic conditions. Diuretic agents are potentially useful in these cases, but their effects on the cardiac fibrosis pathogenesis are yet to be identified. This study was designed to identify and compare the effects of diuretic drugs torasemide and furosemide on cardiac fibrosis in a rat model of dilated cardiomyopathy induced by porcine cardiac myosin mediated experimental autoimmune myocarditis. Gap junction proteins, connexin-43 and N-cadherin, expressions were downregulated in the hearts of CHF rats, while torasemide treatment has upregulated their expression. Western blotting and immunohistochemical analysis for various cardiac fibrosis related proteins as well as histopathological studies have shown that both drugs have potential anti-fibrotic effects. Among them, torasemide has superior efficacy in offering protection against adverse cardiac remodeling in the selected rat model of dilated cardiomyopathy. In conclusion, torasemide treatment has potential anti-fibrotic effect in the hearts of CHF rats, possibly via improving the gap junction proteins expression and thereby improving the cell-cell interaction in the heart. © 2016 BioFactors, 43(2):187-194, 2017.

Effects of the main active components combinations of Astragalus and Panax notoginseng on energy metabolism in brain tissues after cerebral ischemia-reperfusion in mice

Background:

Astragalus and Panax notoginseng are traditional Chinese medicines used for the treatments of cardio-cerebrovascular ischemic diseases, astragaloside IV (AST IV) and ginsenoside Rg1 (Rg1), ginsenoside Rb1 (Rb1), notoginsenoside R1 (R1) are their active components.

Objective:

The purpose of this work was to investigate the effect of AST IV combined with Rg1, Rb1, R1 on energy metabolism in brain tissues after cerebral ischemia-reperfusion in mice.

Materials and Methods:

C57BL/6 mice were randomly divided into 11 groups, treated for 3 days. At 1 h after the last administration, the model of cerebral ischemia-reperfusion injury was established, and brain tissues were detected.

Results:

All drugs increased the contents of adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP) and the level of total adenine nucleotides (TAN), the combinations increased energy charge (EC), the effects of four active components combination were better. The phosphorylation of AMP-activated protein kinaseα1/2 (p-AMPKα1/2) was increased in AST IV, R1, four active components combination, AST IV + Rg1 and AST IV + R1 groups, the increased effect of four active components combination was greater than that of the active components alone and AST IV + Rb1. All drugs increased glucose transporter 3 (GLUT3) mRNA and protein, and the increases of four active components combination were more obvious than those of the active components alone or some two active components combinations.

Conclusion:

Four active components combination of Astragalus and P. notoginseng have the potentiation on improving of energy metabolism, the mechanism underlying might be associated with promoting the activation of AMPKα1/2, enhancing the expression of GLUT3, thus mediating glucose into nerve cells, increasing the supply and intake of glucose.

Suppression of MAPK Signaling and Reversal of mTOR-Dependent MDR1-Associated Multidrug Resistance by 21α-Methylmelianodiol in Lung Cancer Cells

Lung cancer is the leading cause of cancer-related deaths worldwide and remains the most prevalent. Interplay between PI3K/AMPK/AKT and MAPK pathways is a crucial effector in lung cancer growth and progression. These signals transduction protein kinases serve as good therapeutic targets for non-small cell lung cancer (NSCLC) which comprises up to 90% of lung cancers. Here, we described whether 21α-Methylmelianodiol (21α-MMD), an active triterpenoid derivative of Poncirus trifoliate, can display anticancer properties by regulating these signals and modulate the occurrence of multidrug resistance in NSCLC cells. We found that 21α-MMD inhibited the growth and colony formation of lung cancer cells without affecting the normal lung cell phenotype. 21α-MMD also abrogated the metastatic activity of lung cancer cells through the inhibition of cell migration and invasion, and induced G0/G1 cell cycle arrest with increased intracellular ROS generation and loss of mitochondrial membrane integrity. 21α-MMD regulated the expressions of PI3K/AKT/AMPK and MAPK signaling which drove us to further evaluate its activity on multidrug resistance (MDR) in lung cancer cells by specifying on P-glycoprotein (P-gp)/MDR1-association. Employing the established paclitaxel-resistant A549 cells (A549-PacR), we further found that 21α-MMD induced a MDR reversal activity through the inhibition of P-gp/MDR1 expressions, function, and transcription with regained paclitaxel sensitivity which might dependently correlate to the regulation of PI3K/mTOR signaling pathway. Taken together, these findings demonstrate, for the first time, the mechanistic evaluation in vitro of 21α-MMD displaying growth-inhibiting potential with influence on MDR reversal in human lung cancer cells.

Telmisartan treatment targets inflammatory cytokines to suppress the pathogenesis of acute colitis induced by dextran sulphate sodium

The renin angiotensin system (RAS) is essential for the regulation of cardiovascular and renal functions to maintain the fluid and electrolyte homeostasis. Recent studies have demonstrated a locally expressed RAS in various tissues of mammals, which is having pathophysiological roles in those organ system. Interestingly, local RAS has important role during the inflammatory bowel disease pathogenesis. Further to delineate its role and also to identify the potential effects of telmisartan, an angiotensin receptor blocker, we have used a mouse model of acute colitis induced by dextran sulphate sodium. We have used 0.01 and 5mg/kg body weight doses of telmisartan and administered as enema to facilitate the on-site action and to reduce the systemic adverse effects. Telmisartan high dose treatment significantly reduced the disease activity index score when compared with the colitis control mice. In addition, oxidative stress and endoplasmic reticulum stress markers expression were also significantly reduced when compared with the colitis control mice. Subsequent experiments were carried out to investigate some of the mechanisms underlying its anti-inflammatory effects and identified that the mRNA levels of pro-inflammatory cytokines such as tumour necrosis factor α, interleukin 1β, interleukin 6 and monocyte chemoattractant protein 1 as well as cellular DNA damage were significantly suppressed when compared with the colitis control mice. Similarly the apoptosis marker proteins such as cleaved caspase 3 and 7 levels were down-regulated and anti-apoptotic protein Bcl2 level was significantly upregulated by telmisartan treatment. These results indicate that blockade of RAS by telmisartan can be an effective therapeutic option against acute colitis.

Mortality and morbidity in different immunization protocols for experimental autoimmune myocarditis in rats

AIM

We aimed to investigate the histological and clinical presentations of experimental autoimmune myocarditis (EAM) induced by different immunization schemes.

METHODS

Male young Lewis rats were divided into five groups immunized by porcine myocardial myosin: subcutaneously (SC) 2 mg (in two 1-mg doses on day 0 and 7), 0 mg (sham group) subcutaneously into rear footpads (RF), 0.25 mg RF, 0.5 mg RF or 1 mg RF (all RF once on day 0). On day 21, left ventricular (LV) function was assessed by cardiac magnetic resonance imaging and cardiac catheterization. The type and degree of myocardial inflammatory infiltrates were determined by conventional histology and immunohistochemistry.

RESULTS

In the SC immunized rats and in the RF sham group, we observed 0% mortality, while in the actively RF immunized rats, mortality was 20, 20 and 44% for the 0.25 mg, 0.5 mg and 1 mg myosin doses respectively. Morbidity as defined by inflammatory infiltrates on haematoxylin and eosin (HE) staining was 22% in the SC immunized rats, 0% in the RF sham group and 100% in all actively RF immunized groups. We observed augmented relative ventricle weight and spleen weight, increased LV end-diastolic pressure, reduced LV developed pressure and reduced LV ejection fraction in all with myosin-immunized RF groups without any systematic dose effect.

CONCLUSION

Subcutaneous immunization to the neck and flanks did not induce a reproducible EAM, while RF myosin administration reliably led to EAM. Lower myosin doses seem to induce the complete histological and clinical picture of EAM while being associated with lower mortality, non-specific symptoms and animal distress.

Targeting interleukin-22 in psoriasis

Interleukin-22 (IL-22) is an IL-10 family cytokine that was recently discovered to be released by T helper 17 (Th17) cells, Th22 cells, etc. Recently, there is emerging evidence that IL-22 is involved in the development and pathogenesis of psoriasis. For instance, IL-22 can inhibit keratinocyte terminal differentiation and can induce psoriasis-like epidermis alterations; serum IL-22 levels were correlated with the disease severity of psoriasis patients, and IL-22 mRNA was positively expressed in the psoriatic skin lesions, but negatively expressed in the normal controls. All these findings suggest that IL-22 may be implicated in psoriasis; therapeutics targeting IL-22 may have promise as a potential therapeutic target for treating psoriasis. In the present review, we summarize recent advances on the role of IL-22 in the pathogenesis and treatment of psoriasis.

Mitochondrial-related gene expression profiles suggest an important role of PGC-1alpha in the compensatory mechanism of endemic dilated cardiomyopathy

Keshan disease (KD) is an endemic dilated cardiomyopathy with unclear etiology. In this study, we compared mitochondrial-related gene expression profiles of peripheral blood mononuclear cells (PBMCs) derived from 16 KD patients and 16 normal controls in KD areas. Total RNA was isolated, amplified, labeled and hybridized to Agilent human 4 × 44k whole genome microarrays. Mitochondrial-related genes were screened out by the Third-Generation Human Mitochondria-Focused cDNA Microarray (hMitChip3). Quantitative real-time PCR, immunohistochemical and biochemical parameters related mitochondrial metabolism were conducted to validate our microarray results. In KD samples, 34 up-regulated genes (ratios ≥ 2.0) were detected by significance analysis of microarrays and ingenuity systems pathway analysis (IPA). The highest ranked molecular and cellular functions of the differentially regulated genes were closely related to amino acid metabolism, free radical scavenging, carbohydrate metabolism, and energy production. Using IPA, 40 significant pathways and four significant networks, involved mainly in apoptosis, mitochondrion dysfunction, and nuclear receptor signaling were identified. Based on our results, we suggest that PGC-1alpha regulated energy metabolism and anti-apoptosis might play an important role in the compensatory mechanism of KD. Our results may lead to the identification of potential diagnostic biomarkers for KD in PBMCs, and may help to understand the pathogenesis of KD.

The efficacy of edaravone (radicut), a free radical scavenger, for cardiovascular disease

Edaravone was originally developed as a potent free radical scavenger, and has been widely used to treat acute ischemic stroke in Japan since 2001. Free radicals play an important role in the pathogenesis of a variety of diseases, such as cardiovascular diseases and stroke. Therefore, free radicals may be targets for therapeutic intervention in these diseases. Edaravone shows protective effects on ischemic insults and inflammation in the heart, vessel, and brain in experimental studies. As well as scavenging free radicals, edaravone has anti-apoptotic, anti-necrotic, and anti-cytokine effects in cardiovascular diseases and stroke. Edaravone has preventive effects on myocardial injury following ischemia and reperfusion in patients with acute myocardial infarction. Edaravone may represent a new therapeutic intervention for endothelial dysfunction in the setting of atherosclerosis, heart failure, diabetes, or hypertension, because these diseases result from oxidative stress and/or cytokine-induced apoptosis. This review evaluates the potential of edaravone for treatment of cardiovascular disease, and covers clinical and experimental studies conducted between 1984 and 2013. We propose that edaravone, which scavenges free radicals, may offer a novel option for treatment of cardiovascular diseases. However, additional clinical studies are necessary to verify the efficacy of edaravone.

Edaravone alleviates hypoxia-acidosis/reoxygenation-induced neuronal injury by activating ERK1/2

Edaravone, a free radical scavenger, is the first clinical drug of neuroprotection for ischemic stroke patients in the world, and has been shown to be an effective agent to alleviate cerebral ischemic injury. It has been established that acidosis is a common feature of cerebral ischemia and underlies the pathogenesis of ischemic stroke. In the present study, we investigated the role of edaravone in hypoxia-acidosis/reoxygenation (H-A/R)-induced neuronal injury that is partially mediated by the activation of acid-sensing ion channels (ASICs). Here, we observed that pretreatment of cultured neurons with edaravone largely reduced LDH release induced by acidosis or H-A/R. We also found that edaravone exhibited its neuroprotective roles by enhancing brain-derived neurotrophic factor (BDNF) and Bcl-2 expression, suppressing caspase-3 activity and promoting extracellular signal-regulated kinase1/2 (ERK1/2) activation. Furthermore, the addition of MEK (mitogen-activated protein kinase/ERK kinase) antagonists PD98059 and U0126 nearly abolished the beneficial effects of edaravone. Similarly, ASICs blockade produced the protective effects comparable to edaravone administration. These results indicate that edaravone is capable of attenuating H-A/R-mediated neurotoxicity at least partially through activating ERK1/2.

Emerging role of interleukin-22 in autoimmune diseases

Interleukin-22 (IL-22) is an IL-10 family cytokine member that was recently discovered to be mainly produced by Th17 cells. Previous studies have indicated the importance of IL-22 in host defense against Gram-negative bacterial organisms (in gut and lung). Recently, there is emerging evidence that IL-22 is involved in the development and pathogenesis of several autoimmune diseases, such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), multiple sclerosis (MS), Sjögren's syndrome (SS) and psoriasis. Therapeutics targeting IL-22 therefore may have promise for treating various autoimmune diseases. In this review, we discuss the recent progression of the involvement of IL-22 in the development and pathogenesis of autoimmune diseases, as well as its clinical implications and therapeutic potential.