First Report of White Mucus Disease Caused by Fuligo gyrosa on Agrocybe chaxingu in China.

Agrocybe chaxingu is an edible and medicinal mushroom widely cultivated in China (Liu et al. 2021). Agrocybe chaxingu is extremely well-liked for the unique flavor and nutritional value. In May 2021, a serious white mucus disease was observed in the farms of A. chaxingu in the Ganxian district of Ganzhou City, Jiangxi Province, China, with an approximate disease incidence of 20%. In the years of 2022 and 2023, the same white mucus disease on A. chaxingu was observed in the farms in Nanchang City, Jiujiang City and Guangchang County, Jiangxi Province, China. The disease generally occurs on the media, stipe or pileus of A. chaxingu under condition of high humidity. The plasmodial slime molds migrated from the surface of culture media (78% hardwood sawdust, 15% wheat bran, 5% tea seed shell, 1% lime, and 1% gypsum) to the base of fruiting bodies, stipes and finally to pilei, showing as moist, sticky, and white reticulated structures. The infected fruiting bodies of A. chaxingu were completely covered by reticulated plasmodia, displaying a white or pale-yellow color. This resulted in the growth cessation, wilting and eventual death of fruiting body. Microscopic observation found that the plasmodia of slime mold enveloped the hyphae of A. chaxingu, resulting in the fragmentation of the hyphae. The disease can spread quickly, resulting in a 30% reduction in production. Slime mold cultures were isolated by transferring diseased fruiting bodies of A. chaxingu onto oat-agar medium (2% agar and 1% oatmeal) at 25 ℃. The isolates can be obtained after being subcultured for two to three generations. Purified plasmodia were placed on the semi-defined medium (1% tryptone, 1% glucose, 0.15% yeast extract, chick embryo extract and a balanced salt solution) to confirm the absence of bacteria (Daniel et al. 1964) and thus obtained the pure culture. Specimen of the voucher has been deposited in the Institute of Agricultural Applied Microbiology, Jiangxi Academy of Agricultural Sciences as number IAAM-W0002. The vegetative plasmodia have a large and well-developed scalloped structure that were white or milky white in colour. The white plasmodium became opaque pale yellow when exposed to light before fruiting. The veins merged and thickened. Fruiting bodies can be formed on the lid or side of the Petri dish under light condition. The fruiting bodies formed papillae with irregular shape, and then the color changed from translucent yellow to greyish black. Spores were usually spherical or subglobose, free, greyish brown in mass, purplish brown, 7-12 µm in diameter under light microscopy. These morphological characteristics were found to be consistent with those of Fuligo gyrosa (Synonym: Physarum gyrosum) (Kim et al. 2009; Shi et al. 2005; Jahn 1902). The identity of the isolates was further confirmed by sequence analysis of the 18S ribosomal RNA gene with primer SMNUR101/NS4 (Rusk et al. 1995; White et al. 1990). Using BLASTn searches, the sequence of 18S rRNA gene (GenBank accession number OR186216) matched the sequence of F. gyrosa (GenBank accession number LC744593) with the identity of 99.91% and coverage of 97%. A phylogenetic tree based on the 18S rRNA gene also demonstrated that the slime mold clustered with F. gyrosa. Over ten isolates have been obtained from the diseased A. chaxingu samples in different factories and identified as F. gyrosa. To test the pathogenicity of F. gyrosa, five healthy young fruiting bodies (three to five days of primordium) of A. chaxingu cultivated in mushroom-growing room were gently inoculated by a 12 mm diameter oat-agar medium with plasmodia at 24 ± 2 ℃ and then were kept with relative humidity of 90%-95%. Five fruiting bodies inoculated with a 12 mm oat-agar medium served as controls. After 5 days, white mucus characteristics and three fifths of death symptoms were observed on the fruiting bodies inoculated with the plasmodia, while the controls remained asymptomatic. The slime mold on the inoculated fruiting bodies was morphologically identical to F. gyrosa that was observed on the initial diseased fruiting bodies. It was also observed the envelopment A. chaxingu hyphae by the plasmodia of slime mold and fragmentation of the hyphae, and the fragmentation was not observed in the controls. Reisolations were prepared from the inoculated fruiting bodies and confirmed to be F. gyrosa based on morphological characteristics and 18S rRNA sequence, thus fulfilling Koch's postulates. Fuligo gyrosa has been reported to cause severe disease in oriental melon in Korea (Kim et al. 2009). This is the first report of F. gyrosa causing white mucus disease in cultivated A. chaxingu. The findings will provide important information on prevention and control of the disease, and be helpful for the development of A. chaxingu industry.

Novel Therapeutic Potential of Retinoid-Related Orphan Receptor α in Cardiovascular Diseases.

The retinoid-related orphan receptor α (RORα) is one subfamily of nuclear hormone receptors (NRs). This review summarizes the understanding and potential effects of RORα in the cardiovascular system and then analyzes current advances, limitations and challenges, and further strategy for RORα-related drugs in cardiovascular diseases. Besides regulating circadian rhythm, RORα also influences a wide range of physiological and pathological processes in the cardiovascular system, including atherosclerosis, hypoxia or ischemia, myocardial ischemia/reperfusion injury, diabetic cardiomyopathy, hypertension, and myocardial hypertrophy. In terms of mechanism, RORα was involved in the regulation of inflammation, apoptosis, autophagy, oxidative stress, endoplasmic reticulum (ER) stress, and mitochondrial function. Besides natural ligands for RORα, several synthetic RORα agonists or antagonists have been developed. This review mainly summarizes protective roles and possible mechanisms of RORα against cardiovascular diseases. However, there are also several limitations and challenges of current research on RORα, especially the difficulties on the transformability from the bench to the bedside. By the aid of multidisciplinary research, breakthrough progress on RORα-related drugs to combat cardiovascular disorder may appear.

Homokaryotic High-Quality Genome Assembly of Medicinal Fungi Wolfiporia hoelen Reveals Auto-Regulation and High-Temperature Adaption of Probable Two-Speed Genome.

Sclerotia of Wolfiporia hoelen are one of the most important traditional Chinese medicines and are commonly used in China, Japan, Korea, and other Asian countries. In the present study, we presented the first high-quality homokaryotic genome of W. hoelen with 14 chromosomes which was evaluated with assembly index, telomere position detection, and whole-genome collinearity. A 64.44 Mb genome was assembled with a Contig N50 length of 3.76 Mb. The imbalanced distribution of transposons and chromosome characters revealed the probable two-speed genome of W. hoelen. High consistency between methylation and transposon conserved the genome stability. The expansion of the gene family about signal transduction and nutritional transport has intimate relationships with sclerotial formation. Up-regulation of expression for distinctive decomposition enzymes, ROS clearance genes, biosynthesis of unsaturated fatty acids, and change of the cell wall components maintained high-speed growth of mycelia that may be the high-temperature adaption strategy of W. hoelen. Further, the analysis of mating-control genes demonstrated that HD3 probably had no function on mating recognition, with the HD protein in a distant genetic with known species. Overall, the high-quality genome of W. hoelen provided crucial information for genome structure and stability, high-temperature adaption, and sexual and asexual process.

SNO-MLP (S-Nitrosylation of Muscle LIM Protein) Facilitates Myocardial Hypertrophy Through TLR3 (Toll-Like Receptor 3)-Mediated RIP3 (Receptor-Interacting Protein Kinase 3) and NLRP3 (NOD-Like Receptor Pyrin Domain Containing 3) Inflammasome Activation.

BACKGROUND: S-nitrosylation (SNO), a prototypic redox-based posttranslational modification, is involved in the pathogenesis of cardiovascular disease. The aim of this study was to determine the role of SNO of MLP (muscle LIM protein) in myocardial hypertrophy, as well as the mechanism by which SNO-MLP modulates hypertrophic growth in response to pressure overload. METHODS: Myocardial samples from patients and animal models exhibiting myocardial hypertrophy were examined for SNO-MLP level using biotin-switch methods. SNO sites were further identified through liquid chromatography-tandem mass spectrometry. Denitrosylation of MLP by the mutation of nitrosylation sites or overexpression of S-nitrosoglutathione reductase was used to analyze the contribution of SNO-MLP in myocardial hypertrophy. Downstream effectors of SNO-MLP were screened through mass spectrometry and confirmed by coimmunoprecipitation. Recruitment of TLR3 (Toll-like receptor 3) by SNO-MLP in myocardial hypertrophy was examined in TLR3 small interfering RNA-transfected neonatal rat cardiomyocytes and in a TLR3 knockout mouse model. RESULTS: SNO-MLP level was significantly higher in hypertrophic myocardium from patients and in spontaneously hypertensive rats and mice subjected to transverse aortic constriction. The level of SNO-MLP also increased in angiotensin II- or phenylephrine-treated neonatal rat cardiomyocytes. S-nitrosylated site of MLP at cysteine 79 was identified by liquid chromatography-tandem mass spectrometry and confirmed in neonatal rat cardiomyocytes. Mutation of cysteine 79 significantly reduced hypertrophic growth in angiotensin II- or phenylephrine-treated neonatal rat cardiomyocytes and transverse aortic constriction mice. Reducing SNO-MLP level by overexpression of S-nitrosoglutathione reductase greatly attenuated myocardial hypertrophy. Mechanistically, SNO-MLP stimulated TLR3 binding to MLP in response to hypertrophic stimuli, and disrupted this interaction by downregulating TLR3-attenuated myocardial hypertrophy. SNO-MLP also increased the complex formation between TLR3 and RIP3 (receptor-interacting protein kinase 3). This interaction in turn induced NLRP3 (nucleotide-binding oligomerization domain-like receptor pyrin domain containing 3) inflammasome activation, thereby promoting the development of myocardial hypertrophy. CONCLUSIONS: Our findings revealed a key role of SNO-MLP in myocardial hypertrophy and demonstrated TLR3-mediated RIP3 and NLRP3 inflammasome activation as the downstream signaling pathway, which may represent a therapeutic target for myocardial hypertrophy and heart failure.

Sirtuin 3 deficiency exacerbates diabetic cardiomyopathy via necroptosis enhancement and NLRP3 activation.

Sirtuin 3 (SIRT3) is a potential therapeutic target for cardiovascular, metabolic, and other aging-related diseases. In this study, we investigated the role of SIRT3 in diabetic cardiomyopathy (DCM). Mice were injected with streptozotocin (STZ, 60 mg/kg, ip) to induce diabetes mellitus. Our proteomics analysis revealed that SIRT3 expression in the myocardium of diabetic mice was lower than that of control mice, as subsequently confirmed by real-time PCR and Western blotting. To explore the role of SIRT3 in DCM, SIRT3-knockout mice and 129S1/SvImJ wild-type mice were injected with STZ. We found that diabetic mice with SIRT3 deficiency exhibited aggravated cardiac dysfunction, increased lactate dehydrogenase (LDH) level in the serum, decreased adenosine triphosphate (ATP) level in the myocardium, exacerbated myocardial injury, and promoted myocardial reactive oxygen species (ROS) accumulation. Neonatal rat cardiomyocytes were transfected with SIRT3 siRNA, then exposed to high glucose (HG, 25.5 mM). We found that downregulation of SIRT3 further increased LDH release, decreased ATP level, suppressed the mitochondrial membrane potential, and elevated oxidative stress in HG-treated cardiomyocytes. SIRT3 deficiency further raised expression of necroptosis-related proteins including receptor-interacting protein kinase 1 (RIPK1), RIPK3, and cleaved caspase 3, and upregulated the expression of inflammation-related proteins including NLR family pyrin domain-containing protein 3 (NLRP3), caspase 1 p20, and interleukin-1ß both in vitro and in vivo. Collectively, SIRT3 deficiency aggravated hyperglycemia-induced mitochondrial damage, increased ROS accumulation, promoted necroptosis, possibly activated the NLRP3 inflammasome, and ultimately exacerbated DCM in the mice. These results suggest that SIRT3 can be a molecular intervention target for the prevention and treatment of DCM.

Necroptosis Inhibition by Hydrogen Sulfide Alleviated Hypoxia-Induced Cardiac Fibroblasts Proliferation via Sirtuin 3.

Myocardial ischemia or hypoxia can induce myocardial fibroblast proliferation and myocardial fibrosis. Hydrogen sulfide (H2S) is a gasotransmitter with multiple physiological functions. In our present study, primary cardiac fibroblasts were incubated with H2S donor sodium hydrosulfide (NaHS, 50 µM) for 4 h followed by hypoxia stimulation (containing 5% CO2 and 1% O2) for 4 h. Then, the preventive effects on cardiac fibroblast proliferation and the possible mechanisms were investigated. Our results showed that NaHS reduced the cardiac fibroblast number, decreased the hydroxyproline content; inhibited the EdU positive ratio; and down-regulated the expressions of α-smooth muscle actin (α-SMA), the antigen identified by monoclonal antibody Ki67 (Ki67), proliferating cell nuclear antigen (PCNA), collagen I, and collagen III, suggesting that hypoxia-induced cardiac fibroblasts proliferation was suppressed by NaHS. NaHS improved the mitochondrial membrane potential and attenuated oxidative stress, and inhibited dynamin-related protein 1 (DRP1), but enhanced optic atrophy protein 1 (OPA1) expression. NaHS down-regulated receptor interacting protein kinase 1 (RIPK1) and RIPK3 expression, suggesting that necroptosis was alleviated. NaHS increased the sirtuin 3 (SIRT3) expressions in hypoxia-induced cardiac fibroblasts. Moreover, after SIRT3 siRNA transfection, the inhibitory effects on cardiac fibroblast proliferation, oxidative stress, and necroptosis were weakened. In summary, necroptosis inhibition by exogenous H2S alleviated hypoxia-induced cardiac fibroblast proliferation via SIRT3.

SIRT3 deficiency delays diabetic skin wound healing via oxidative stress and necroptosis enhancement.

Sirtuin 3 (SIRT3) plays a vital role in several dermatological diseases. However, the role and detailed mechanism of SIRT3 in diabetic wound healing are unknown well yet. To explore possible involvement of SIRT3 and necroptosis in diabetic skin wound healing, SIRT3 knockout (KO) mice and 129S1/SvImJ wild-type (WT) mice were injected with streptozotocin (STZ), and mice skin fibroblasts were exposed to high glucose (HG). It was found that SIRT3 expression decreased in the skin of diabetic patients. SIRT3 deficiency delayed healing rate, reduced blood supply and vascular endothelial growth factor expression, promoted superoxide production, increased malondialdehyde (MDA) levels, decreased total antioxidant capacity (T-AOC), reduced superoxide dismutase (SOD) activity and aggravated ultrastructure disorder in skin wound of diabetic mice. SIRT3 deficiency inhibited mice skin fibroblasts migration with HG stimulation, which was restored by SIRT3 overexpression. SIRT3 deficiency also suppressed α-smooth muscle actin (α-SMA) expression, enhanced superoxide production but decreased mitochondrial membrane potential with HG stimulation after scratch. SIRT3 deficiency further elevated receptor-interacting protein kinase 3 (RIPK3), RIPK1 and caspase 3 expression both in vitro and in vivo. Collectively, SIRT3 deficiency delayed skin wound healing in diabetes, the mechanism might be related to impaired mitochondria function, enhanced oxidative stress and increased necroptosis. This may provide a novel therapeutic target to accelerate diabetic skin wound healing.

Mogrol attenuates lipopolysaccharide (LPS)-induced memory impairment and neuroinflammatory responses in mice.

This study aimed to evaluate whether mogrol, a main bioactive ingredient of Siraitia grosvenorii, could attenuate LPS-induced memory impairment in mice. The behavioral tests and immunohistochemical analysis and Western blot were performed. The present results showed that oral administration of mogrol (20, 40, 80 mg/kg) significantly improved LPS-induced memory impairment in mice. The results also indicated that mogrol treatment significantly reduced the number of Iba1-positive cells, the nuclear NF-κB p65 and levels of TNF-α, IL-1ß and IL-6 both in the hippocampus and frontal cortex of LPS-challenged mice. [Formula: see text].

Dihydromyricetin Improves Endothelial Dysfunction in Diabetic Mice via Oxidative Stress Inhibition in a SIRT3-Dependent Manner.

Dihydromyricetin (DHY), a flavonoid component isolated from Ampelopsis grossedentata, exerts versatile pharmacological activities. However, the possible effects of DHY on diabetic vascular endothelial dysfunction have not yet been fully elucidated. In the present study, male C57BL/6 mice, wild type (WT) 129S1/SvImJ mice and sirtuin 3 (SIRT3) knockout (SIRT3-/-) mice were injected with streptozotocin (STZ, 60 mg/kg/day) for 5 consecutive days. Two weeks later, DHY were given at the doses of 250 mg/kg by gavage once daily for 12 weeks. Fasting blood glucose (FBG) and glycosylated hemoglobin (HbA1c) level, endothelium-dependent relaxation of thoracic aorta, reactive oxygen species (ROS) production, SIRT3, and superoxide dismutase 2 (SOD2) protein expressions, as well as mitochondrial Deoxyribonucleic Acid (mtDNA) copy number, in thoracic aorta were detected. Our study found that DHY treatment decreased FBG and HbA1c level, improved endothelium-dependent relaxation of thoracic aorta, inhibited oxidative stress and ROS production, and enhanced SIRT3 and SOD2 protein expression, as well as mtDNA copy number, in thoracic aorta of diabetic mice. However, above protective effects of DHY were unavailable in SIRT3-/- mice. The study suggested DHY improved endothelial dysfunction in diabetic mice via oxidative stress inhibition in a SIRT3-dependent manner.

Hippocampal Genetic Knockdown of PPARδ Causes Depression-Like Behaviors and Neurogenesis Suppression.

BACKGROUND: Although depression is the leading cause of disability worldwide, its pathophysiology is poorly understood. Our previous study showed that hippocampal peroxisome proliferator-activated receptor δ (PPARδ) overexpression displays antidepressive effect and enhances hippocampal neurogenesis during chronic stress. Herein, we further extended our curiosity to investigate whether downregulating PPARδ could cause depressive-like behaviors through downregulation of neurogenesis. METHODS: Stereotaxic injection of lentiviral vector, expressing short hairpin RNA complementary to the coding exon of PPARδ, was done into the bilateral dentate gyri of the hippocampus, and the depression-like behaviors were observed in mice. Additionally, hippocampal neurogenesis, brain-derived neurotrophic factor and cAMP response element-binding protein were measured both in vivo and in vitro. RESULTS: Hippocampal PPARδ knockdown caused depressive-like behaviors and significantly decreased neurogenesis, neuronal differentiation, levels of mature brain-derived neurotrophic factor and phosphorylated cAMP response element-binding protein in the hippocampus. In vitro study further confirmed that PPARδ knockdown could inhibit proliferation and differentiation of neural stem cells. Furthermore, these effects were mimicked by repeated systemic administration of a PPARδ antagonist, GSK0660 (1 or 3 mg/kg i.p. for 21 d). CONCLUSIONS: These findings suggest that downregulation of hippocampal PPARδ is associated with depressive behaviors in mice through an inhibitory effect on cAMP response element-binding protein/brain-derived neurotrophic factor-mediated adult neurogenesis in the hippocampus, providing new insights into the pathogenesis of depression.

Exogenous hydrogen sulphide supplement accelerates skin wound healing via oxidative stress inhibition and vascular endothelial growth factor enhancement.

Hydrogen sulphide (H2 S) is an important gasotransmitter with several physiological functions. However, the roles and the detailed mechanisms of H2 S on skin wound healing are not known well. In the present study, 129S1/SvImJ mice were intraperitoneally injected with NaHS (50 µmol/kg/d) for 2 weeks. Then, a round wound of 6 mm diameter with depth into the dermis was made. The skin wound area, blood perfusion, superoxide production, malondialdehyde (MDA) levels, total antioxidant capacity (T-AOC), expression of vascular endothelial growth factor (VEGF), dynamin-related protein 1 (DRP1) and optic atrophy 1 (OPA1) were measured. After NaHS (50 µmol/L) pre-administration for 4 hours, cell migration rate, DRP1, OPA1 and α-smooth muscle actin (α-SMA) expression, superoxide production and mitochondrial membrane potential in primary skin fibroblasts were measured. Tube formation in human umbilical vein endothelial cells (HUVECs) and cell migration in human keratinocytes were also measured. The results showed that NaHS pretreatment significantly accelerated wound healing and improved blood flow in the wound after operation. NaHS increased VEGF expression in the wound and promoted tube formation in HUVECs. Meanwhile, NaHS attenuated reactive oxygen species (ROS) production, suppressed MDA level but restored T-AOC in the wound. NaHS also promoted skin fibroblasts migration and α-SMA expression after scratch. Moreover, NaHS alleviated ROS, increased mitochondrial membrane potential, decreased DRP1 but enhanced OPA1 expression in skin fibroblasts after scratch. NaHS also accelerated human keratinocytes migration after scratch. Taken together, exogenous H2 S supplementary accelerated the skin wound healing, which might be related to oxidative stress inhibition and VEGF enhancement.

Sirtuin3 deficiency exacerbates carbon tetrachloride-induced hepatic injury in mice.

Sirtuin3 (SIRT3) plays an important role in maintaining normal mitochondrial function and alleviating oxidative stress. After carbon tetrachloride (CCl4 ) administration, the expression of SIRT3 decreased in the liver of mice, which indicated that the SIRT3 might play a crucial role during chemical-induced acute hepatic injury. To verify the hypothesis, CCl 4 was given to induce acute hepatic injury in SIRT3 knockout (KO) mice and wild-type (WT) mice. CCl 4 -induced liver injury was more severe in SIRT3 KO mice compared with the WT mice. In addition, the oxidative stress induced by CCl 4 was enhanced in the SIRT3 KO mice. Furthermore, the increased expression of dynamin-related protein 1 was also aggravated in SIRT3 KO mice after CCl 4 administration. In conclusion, our study demonstrated that SIRT3 deficiency exacerbated CCl 4 -induced impairment of the liver in mice, and the mechanism might be related to enhanced oxidative stress.

Dihydromyricetin Attenuates Myocardial Hypertrophy Induced by Transverse Aortic Constriction via Oxidative Stress Inhibition and SIRT3 Pathway Enhancement.

Dihydromyricetin (DMY), one of the flavonoids in vine tea, exerts several pharmacological actions. However, it is not clear whether DMY has a protective effect on pressure overload-induced myocardial hypertrophy. In the present study, male C57BL/6 mice aging 8⁻10 weeks were subjected to transverse aortic constriction (TAC) surgery after 2 weeks of DMY (250 mg/kg/day) intragastric administration. DMY was given for another 2 weeks after surgery. Blood pressure, myocardial structure, cardiomyocyte cross-sectional area, cardiac function, and cardiac index were observed. The level of oxidative stress in the myocardium was assessed with dihydroethidium staining. Our results showed that DMY had no significant effect on the blood pressure. DMY decreased inter ventricular septum and left ventricular posterior wall thickness, relative wall thickness, cardiomyocyte cross-sectional areas, as well as cardiac index after TAC. DMY pretreatment also significantly reduced arterial natriuretic peptide (ANP), brain natriuretic peptide (BNP) mRNA and protein expressions, decreased reactive oxygen species production and malondialdehyde (MDA) level, while increased total antioxidant capacity (T-AOC), activity of superoxide dismutase (SOD), expression of sirtuin 3 (SIRT3), forkhead-box-protein 3a (FOXO3a) and SOD2, and SIRT3 activity in the myocardium of mice after TAC. Taken together, DMY ameliorated TAC induced myocardial hypertrophy in mice related to oxidative stress inhibition and SIRT3 pathway enhancement.

[Research Advances in Hydrogen Sulfide and Diabetes Mellitus as Well as Diabetic Complications].

Diabetes and its complications continue to be an increasing global health problem. Hydrogen sulfide (H2S)has emerged as the third gasotransmitter following the nitric oxide and carbon monoxide in the body, and plays an important role in both physiology and pathophysiology. Recent work has suggested important roles for H2S in the regulation of pancreatic ß-cell function, as well as development of insulin resistance and diabetic complications. Targeting H2S represents a novel therapeutic approach in diabetes and its associated complications. This review article summarizes the current body of evidence regarding the role of H2S in diabetes mellitus, and especially in its associated vascular complications, as well as the underlying signaling mechanisms.

Aliskiren protects against myocardial ischaemia-reperfusion injury via an endothelial nitric oxide synthase dependent manner.

Aliskiren, a direct renin inhibitor, has shown potent ability to attenuate hypertension. Our previous research has found that aliskiren protected against myocardial ischaemia-reperfusion (I/R) injury and enhanced phosphorylation of endothelial nitric oxide synthase (eNOS) in spontaneously hypertensive rats. However, whether the cardioprotective effect of aliskiren against myocardial I/R injury was eNOS-dependent is unknown. In the present study, 12-week-old male eNOS knockout (eNOS-/- ) and wild-type C57BL/6J mice (WT) were orally administrated with the dose of 50 mg/kg per day of aliskiren. After a 4-week treatment, aliskiren decreased blood pressure in eNOS-/- mice, and reduced renin-angiotension II levels in both eNOS-/- and WT mice. Aliskiren also improved left ventricular ejection fraction (EF) and fractional shortening (FS), decreased myocardial infarct size, reduced creatine kinase (CK) and lactate dehydrogenase (LDH) activity in plasma, attenuated dihydroethidium (DHE) fluorescence and levels of malondialdehyde (MDA), enhanced superoxide dismutase (SOD) activity and total antioxidant capacity (T-AOC) in myocardium, increased SOD and thioredoxin (Trx) proteins expression in WT mice subjected to 30 minutes of ischaemia followed by reperfusion for 24 hours. However, aliskiren failed to restore all of the above indices in eNOS-/- mice subjected to the same I/R injury. Our study indicated that aliskiren protected against myocardial I/R injury via an eNOS dependent manner.

Tetrahydroxystilbene glucoside inhibits TNF-α-induced migration of vascular smooth muscle cells via suppression of vimentin.

Vascular smooth muscle cell (VSMC) migration triggered by TNF-α is an important event that occurs during the development of atherosclerosis. 2,3,5,4'-Tetrahydroxystilbene-2-O-ß-d-glucoside (TSG) has been proven to exhibit significant anti-atherosclerotic activity. Herein we investigate the inhibitory effect of TSG on TNF-α-induced VSMC migration and explore the underlying mechanisms. TSG pretreatment markedly inhibited TNF-α-induced cell migration. The inhibition of vimentin redistribution and expression was involved in the inhibitory effect of TSG on VSMC migration. The suppression of vimentin expression by shRNA in VSMCs significantly inhibited TNF-α-induced cell migration. Furthermore, TSG inhibited the TNF-α-induced expression of TGFß1 and TGFßR1, and phosphorylation of TGFßR1 and Smad2/3. TSG also suppressed the nuclear translocation of Smad4 induced by TNF-α. These results suggest that TSG inhibits VSMC migration induced by TNF-α through inhibiting vimentin rearrangement and expression. The interruption of TGFß/Smad pathway appears to be responsible for the suppression of TSG on vimentin expression.

Aliskiren improves endothelium-dependent relaxation of thoracic aorta by activating PI3K/Akt/eNOS signal pathway in SHR.

Aliskiren, a direct renin blocker, has been approved for the treatment of hypertension. However, the potential role of aliskiren on vascular endothelial function in spontaneously hypertensive rats (SHR) remains unclear. In the present study, male SHRs at 12 weeks of age were orally administrated 30 mg/kg per day or 60 mg/kg per day aliskiren. After a 4-week treatment, aliskiren showed a significant effect on the reduction of blood pressure at a dosage of 60 mg/kg per day, but not of 30 mg/kg per day. Moreover, both dosages of aliskiren improved endothelium-dependent relaxation, reduced dihydroethidium fluorescence intensity, decreased level of malondialdehyde but heightened total antioxidant capacity and superoxide dismutase activity in thoracic aorta in SHR. Aliskiren also markedly increased expression of p85α, an important subunit of phosphatidylinositol 3 kinase (PI3K), enhancing phosphorylation of protein kinase B (Akt) at Ser473 and endothelial nitric oxide synthase (eNOS) at Ser1177, as well as cyclic guanosine-3'5'-monophosphate (cGMP, a sensitive index of biological activity of nitric oxide) concentration. Furthermore, both anti-oxidative and endothelium protective effects of aliskiren were diminished when PI3K was inhibited in vivo. The data presented here indicates that, aliskiren improves endothelium-dependent relaxation of thoracic aorta in SHR, predominantly through attenuating oxidative stress and activation of the PI3K/Akt/eNOS pathway. These data might propose novel strategies to prevent and improve vascular endothelial dysfunction.

Derivation of iPSCs in stirred suspension bioreactors.

Induced pluripotent stem cells (iPSCs) are typically derived in adherent culture. Here we report fast and efficient derivation of mouse iPSCs in stirred suspension bioreactors, with and without the use of c-Myc. Suspension-reprogrammed cells expressed pluripotency markers, showed multilineage differentiation in vitro and in vivo, and contributed to the germline in chimeric mice. Suspension reprogramming has the potential to accelerate and standardize iPSC research.

Attenuating effects of dihydromyricetin on angiotensin II-induced rat cardiomyocyte hypertrophy related to antioxidative activity in a NO-dependent manner.

CONTEXT: Dihydromyricetin (DMY) displays a range of biological properties. However, whether DMY attenuates cardiomyocyte hypertrophy is unknown. OBJECTIVE: To investigate whether DMY had potential therapeutic value to protect against angiotensin II (Ang II)-induced cardiomyocyte hypertrophy. MATERIALS AND METHODS: Neonatal rat cardiomyocytes were pretreated with DMY (0-320 µM) followed with Ang II (100 nM) stimulation for 24 h, and then degree of hypertrophy was evaluated by cell surface analysis. Levels of reactive oxygen species (ROS) were measured with 2',7'-dichlorfluorescein-diacetate (DCFH-DA) fluorescent staining. Antioxidative activity was evaluated by malondialdehyde (MDA) level, superoxide dismutase (SOD) activity, and total antioxidant capacity (T-AOC). Cyclic guanosine monophosphate (cGMP) was determined with a radioimmunoassay. RESULTS: Pre-incubation with DMY (20, 40, 80, and 160 µM) for 8 h, 12 h, 24 h, or 48 h decreased cell surface areas. It down-regulated mRNA expression of atrial natriuretic factor (1.95- to 1.24-fold) and ß-myosin heavy chains (3.51- to 2.32-fold), reduced levels of MDA as well as increased SOD activity and T-AOC. Expression of SOD and thioredoxin were enhanced by DMY, whereas p22(phox) and phosphorylation of mitogen-activated protein kinases were inhibited. Content of cGMP (0.54- to 0.80-fold) and phosphorylation of endothelial nitric oxide synthase at serine 1177 (0.70- to 1.05-fold) were augmented by DMY. Moreover, attenuating effect of DMY on hypertrophy was abolished when NO production was inhibited by l-NAME. CONCLUSION: Attenuating effects of DMY on Ang II-induced cardiomyocyte hypertrophy related to antioxidative activity in a NO-dependent manner.