Amelioration of mitochondrial dysfunction in heart failure through S-sulfhydration of Ca^2＋/calmodulin-dependent protein kinase Ⅱ

OBJECTIVE To determine the functional role of hydrogen sulfide(H_2S) in protecting against mitochondrial dysfunction in heart failure through the inhibition of Ca^(2+)/calmodulin-dependent protein kinaseⅡ(Ca MKⅡ) using wild type and CSE knockout mouse models.METHODS Continuous subcutaneous injection isoprenaline(7.5 mg·kg^(-1) per day),once a day for 4 weeks to induce heart failure in male C57BL/6(6-8 weeks old) mice and CSE-/-mice.150 μmol·L^(-1) H_2O_2 was used to induce oxidative stress in H9c2 cells.Echocardiograph was used to detect cardiac parameters.H&E stain and Masson stain was to observation histopathological changes.Western blot was used to detect protein expression and activity.The si RNA was used to silence protein expression.HPLC was used to detect H_2S level.Biotin assay was used to detect the level of S-sulfhydration protein.RESULTS Treatment with S-propyl-L-cysteine(SPRC) or sodium hydrosulfide(Na HS),modulators of blood H_2S levels,attenuated the development of heart failure in animals,reduced lipid peroxidation,and preserved mitochondrial function.The inhibition Ca MKⅡ phosphorylation by SPRC and Na HS as demonstrated using both in vivo and in vitro models corresponded with the cardioprotective effects of these compounds.Interestingly,Ca MKⅡ activity was found to be elevated in CSE-/-mice as compared to wild type animals and the phosphorylation status of Ca MK Ⅱ appeared to relate to the severity of heart failure.Importantly,in wild type mice SPRC was found to promote S-sulfhydration of Ca MKⅡ leading to reduced activity of this protein however,in CSE-/-mice S-sulfhydration was abolished following SPRC treatment.CONCLUSION A novel mechanism depicting a role of S-sulfhydration in the regulation of Ca MKⅡ is presented.SPRC mediated S-sulfhydration of Ca MKⅡ was found to inhibit Ca MKⅡ activity and to preserve cardiovascular homeostasis.

Ginsenoside modified lipid-coated perfluorocarbon nanodroplets: A novel approach to reduce complement protein adsorption and prolong in vivo circulation

Lipid-coated perfluorocarbon nanodroplets(lp-NDs)hold great promise in bio-medicine as vehicles for drug delivery,molecular imaging and vaccine agents.However,their clinical utility is restricted by limited targeted accumulation,attributed to the innate immune system(IIS),which acts as the initial defense mechanism in humans.This study aimed to optimize lp-ND formulations to mini-mize non-specific clearance by the IIS.Ginsenosides(Gs),the principal components of Panax ginseng,possessing complement inhibition ability,structural similarity to cholesterol,and comparable fat solubi-lity to phospholipids,were used as promising candidate IIS inhibitors.Two different types of ginsenoside-based Ip-NDs(Gs Ip-NDs)were created,and their efficacy in reducing IS recognition was examined.The Gs p-NDs were observed to inhibit the adsorption of C3 in the protein corona(PC)and the generation of SC5b-9.Adding Gs to Ip-NDs reduced complement adsorption and phagocytosis,resulting in a longer blood circulation time in vivo compared to lp-NDs that did not contain Gs.These results suggest that Gs can act as anti-complement and anti-phagocytosis adjuvants,potentially reducing non-specific clear-ance by the IS and improving lifespan.

Evaluation on monoamine neurotransmitters changes in depression rats given with sertraline, meloxicam or/and caffeic acid

Inflammation drives the development of depression and may affect neurotransmitters and thus neurocircuits increase the risk of depression.To investigate the influence of inhibition of inflammatory pathways on the biogenic amine neurotransmitters metabolism in depressive rats,sertraline,and meloxicam,the inhibitors of arachidonic acid-cyclooxygenase-2/lipoxygenase(AA-COX-2/5-LO)pathways,were given to depressive rats.After the development of depression model by chronic unpredictable mild stress(CUMS)for 6 weeks,Successful modeling rats were selected and randomly divided into CUMS group and medication administration group.After given medicine,The biogenic amine neurotransmitters in rat cortex and hippocampus were measured by high-performance liquid chromatography equipped with an electrochemical detector(HPLC-ECD).Compared with the normal group,the concentration of norepinephrine(NE)significantly decreased and the concentrations of Tyrosine(Tyr),Tryptophan(Trp),3,4-dihydroxyphenyl acetic acid(DOPAC),3-methoxy-4-hydroxyphenylglycol(MHPG),homovanillic acid(HVA)and 5-hydroxyindoleacetic acid(5-HIAA)significantly increased in the CUMS group.Sertraline significantly inhibited the elevation of 5-HIAA.Meloxicam inhibited the decrease of NE level in CUMS-induced rat and the increase of Trp,MHPG,and 5-HIAA level in a dose-dependent manner.Caffeic acid inhibited the decrease of NE and the increase of Trp and MHPG in a dose-dependent manner.The inhibition of AA-COX-2/5-LO pathways can improve the behaviors of depression rats and suppress CUMSinduced changes in biogenic amines.Compared with the single-dose lipoxygenase(5-LO)or Cyclooxygenase-2(COX-2)inhibitor,the combination treatment with meloxicam 1 mg/kg and caffeic acid 10 mg/kg have no significant improvement in CUMS-induced depression behavior and the level of cortical monoamine neurotransmitters and their metabolites.

Expression of MICU1 after experimental focal cerebral ischemia in adult rats

Background: Mitochondrial Ca2+ uptake is a pivotal pathophysiological process for neuronal survival when subjected to ischemic insult. Mitochondrial calcium uptake 1 (MICU1) has been demonstrated as a key regulator of the mitochondrial calcium uniporter (MCU), identified as a tetrameric highly specific channel that modulates mitochondrial Ca2+ uptake. Methods: Adult male Sprague–Dawley (SD) rats underwent middle cerebral artery occlusion (MCAO) to create the standard focal cerebral ischemia model. The permanent MCAO approach utilized the intraluminal approach. Neurological examination, and subsequent histological characterization of cerebral infarcts using triphenyltetrazolium chloride staining, as well as Western blot, immunohistochemical staining, and real-time quantitative polymerase chain reaction assays were employed to assess the functional effects of MICU1 and its expression in the brain.Results: Animals exposed to MCAO displayed the typical neurological deficit accompanied by cortical and subcortical infarction at 72 h post-stroke. The expression of MICU1, with co-localization with neurons, was detected at different time points (6 h and 12 h) after ischemic damage. Altogether, these observations revealed an up-regulation of MICU1 expression in the early stages of cerebral ischemia.Conclusion: The results demonstrated that MICU1 was upregulated in neurons at the acute phase of ischemic stroke. Because MICU1 has been previously shown to participate in mitochondrial Ca2+ uptake mediated by MCU, our study further implicates the involvement of MICU1 in calcium overload-induced cell death which is closely associated with stroke.

Ultra-homogeneous Cu_(2-x)Se nanoparticles as near-infraredⅡplasmonic phototheranstics for photothermal/chemodynamic synergistic therapy of liver cancer

Laser mediated photothermal/chemodynamic co-therapy is widely applied for anti-cancer treatment due to its good therapeutic effect.However,the laser wavelength for effectively targeting deep tumor tissues can decide whether or not it is a key premise of irradiation treatment.In this study,a super-homogenous and highly dispersive spherical nanoparticle Cu_(2-x)Se was prepared,which displayed a strong surface plasmon resonance(SPR)peak in the near-infrared region(NIR)-Ⅱand high Fenton catalytic efficiency.The results of in vitro experiments showed that Cu_(2-x)Se nanoparticles exhibited high photothermal conversion efficiency under the excitation of NIR-Ⅱlaser irradiation,which significantly improved its ability to produce OH.In a tumor-bearing mouse model,the combination of Cu_(2-x)Se and photothermal/chemodynamic co-therapy guided by the real-time photoacoustic imaging in the NIR-Ⅱcould effectively inhibit tumor growth and exhibit good in vivo/in vitro biocompatibility.In summary,this Cu_(2-x)Se nanoparticle-based NIR-Ⅱlaser-mediated photothermal/chemodynamic co-therapy strategy is expected to provide a new option for the diagnosis and treatment of liver cancer.

Identification of hedgehog signaling as a potential oncogenic driver in an aggressive subclass of human hepatocellular carcinoma: A reanalysis of the TCGA cohort

Hepatocellular carcinoma(HCC)is a heterogeneous disease and the second most common cause of cancer-related death worldwide.Marked developments in genomic technologies helped scientists to understand the heterogeneity of HCC and identified multiple HCC-related molecular subclasses.An integrative analysis of genomic datasets including 196 patients from The Cancer Genome Atlas(TCGA)group has recently reported a new HCC subclass,which contains three subgroups(iCluster1,iCluster2,and iCluster3).However,the transcriptional molecular characteristics underlying the iClusters have not been thoroughly investigated.Herein,we identified a more aggressive subset of HCC patients in the iCluster1,and re-clustered the TCGA samples into novel HCC subclasses referred to as aggressive(Ag),moderate-aggressive(M-Ag),and less-aggressive(L-Ag)subclasses.The Ag subclass had a greater predictive power than the TCGA iCluster1,and a higher level of alpha fetoprotein,microscopic vascular invasion,immune infiltration,isocitrate dehydrogenase 1/2 mutation status,and a worse survival than MAg and L-Ag subclasses.Global transcriptomic analysis showed that activation of hedgehog signaling in the Ag subclass may play key roles in tumor development of aggressive HCC.GLI1,a key transcriptional regulator of hedgehog signaling upregulated in the Ag subclass,was correlated with poor prognosis of HCC,and may be a potential prognostic biomarker and therapeutic target for Ag subclass HCC patients.