Dihydroartemisinin inhibits restenosis after balloon angioplasty via circHSPA4/miR-19a-5p axis.

Dihydroartemisinin (DHA) inhibits restenosis following balloon angioplasty. However, data on the mechanisms of DHA activity in restenosis remains scant. Here, we investigated the role of circRNAs in mediating the inhibitory activity of DHA in neointimal formation. We used total RNA sequencing data to profile the expression of mRNA, circRNA and small RNA in sham, vascular balloon injury (VBI) and DHA-treated groups. CCK8 and EdU assays were employed to analyze cell proliferation, while qRT-PCR and Western blot were used to analyze the RNA or protein expression. In addition, we used RNA immunoprecipitation and luciferase reporter assay to assess the binding of circHSPA4 with miR-19a-5p. RNA sequencing demonstrated that circHSPA4 was upregulated in VBI. Treatment with DHA effectively suppressed the upregulation of the circHSPA4. In addition, analysis of platelet-derived growth family factor bb (PDGFbb)-induced HA-VSMCs showed upregulation of circHSPA4, which was associated with cell proliferation and differentiation. CircHSPA4 was shown to induce dedifferentiation and proliferation of smooth muscle cells. PDGFBB-induced overexpression of CircHSPA4 in HA-VSMCs led to suppression of miR-19a-5p, a phenomenon that was reversed by DHA, in concentration-dependent fashion. In addition, miR-19a-5p reduced the dedifferentiation and proliferation of the smooth muscle cells. Our data demonstrated that CircHSPA4 regulates proliferation and differentiation of smooth muscle cells. DHA and miR-19a-5p modulates CircHSPA4 and can be used as coated drugs on balloon catheter to improve the success rate of vascular remodeling.

Effects of extrusion on physical properties of glutinous rice and its application in the improvement of quality characteristics of glutinous rice products.

This study investigated the effects of extrusion on the physical properties of glutinous rice and addressed the challenges associated with its hardened texture and reduced taste in glutinous rice products by adding extruded glutinous rice to assess their anti-retrogradation effect compared with different improvers. Glutinous rice flour with different gelatinization degrees was obtained by changing the initial moisture content of glutinous rice grains before extrusion, and their physicochemical properties and the effect of adding them to rice products were analyzed. Results showed that with the increase in moisture content, the viscosity, water absorption index of extruded glutinous rice flour, and product viscosity increased, while the gelatinization degree, water solubility index, and product elasticity decreased, and the hardness of the rice products showed a trend of first decreasing and then increasing. Twenty percent moisture content of glutinous rice products showed the best properties mentioned above. The effects of adding different improvers on retrogradation degree, quality characteristics, microstructure, and moisture migration of glutinous rice products were analyzed by texture profile analysis, sensory evaluation, scanning electron microscopy, and low-field nuclear magnetic resonance. It was found that soybean polysaccharides, xanthan gum, and extruded glutinous rice flour had better anti-retrogradation effects, while colloid and soybean polysaccharides provided a tighter and more three-dimensional internal structure to the rice products. Our study showed that extruded glutinous rice flour had good anti-retrogradation properties and little effect on flavor and taste, but it would increase the roughness and viscosity of the products, which had advantages and disadvantages compared with other improvers.

Research and design of an intelligent fish tank system.

In order to improve the hardware configuration and interaction mode of the fish tank system and realize the diversification of client functions, the purpose of real-time remote monitoring and management is achieved. A set of IoT intelligent fish tank system composed of sensor unit, signal processing unit and wireless transmission unit was designed. The system improves the algorithm of the data collected by the sensor, and proposes an improved first-order lag average filtering algorithm. The system uses composite collection information, intelligent processing, chart data analysis and other methods to transmit the processed data to the cloud server through the WIFI communication module. An APP is designed on the remote monitoring and control end, and a visual data interface of the smart fish tank is made, and the user can modify the environmental parameters conducive to the biological survival inside the fish tank through the APP, it brings great convenience to the family fish tank, and the test shows that the system network is stable and fast in response, and the overall purpose of the intelligent fish tank system is achieved.

Alisol A attenuates malignant phenotypes of colorectal cancer cells by inactivating PI3K/Akt signaling.

Despite the advancement in the diagnosis and therapeutic strategies for colorectal cancer, the outcomes of patients with colorectal cancer remain unsatisfactory. Alisol A is a natural constituent of Alismatis rhizoma (zexie) and has demonstrated anti-cancer properties; however, the function of Alisol A in colorectal cancer is still unknown. In the present study, the effect of Alisol A on colorectal cancer progression was investigated. MTT and colony formation assays showed that treatment with Alisol A repressed colorectal cancer cell proliferation in a dose-dependent manner. Similarly, western blot analysis demonstrated that Alisol A upregulated E-cadherin protein expression levels, but downregulated N-cadherin and Vimentin protein expression levels in colorectal cancer cells. In addition, the number of cells in G0/G1 phase was enhanced, while that of S phase was reduced in Alisol A-treated colorectal cancer cells. Apoptosis and pyroptosis of colorectal cancer cells were stimulated following treatment with Alisol A. Alisol A suppressed the migration ability of colorectal cancer cells in a dose-dependent manner. Moreover, Alisol A increased the chemotherapeutic sensitivity of colorectal cancer cells to cisplatin. Mechanically, western blot analysis confirmed that Alisol A repressed the phosphorylation levels of PI3K, Akt and mTOR in colorectal cancer cells. The Akt activator, SC79 reversed the effect of Alisol A on colorectal cancer cell proliferation and apoptosis. In conclusion, Alisol A induced an inhibitory effect on colorectal cancer progression by inactivating PI3K/Akt signaling.

Effects of arbuscular mycorrhizal fungi on accumulation and translocation of selenium in winter wheat.

BACKGROUND: Selenium (Se) is an essential micronutrient for humans and animals, but not for plants. Generally, cereals including wheat and rice are the main source of dietary Se for humans. Although arbuscular mycorrhizal fungi (AMF) are ubiquitous soil microbes and commonly develop symbionts with winter wheat (Triticum aestivum L.), the influence of AMF on accumulation and translocation of Se during developmental cycle of winter wheat is still unclear. RESULTS: Based on a pot trial, the present results indicated that the effects of AMF on grain Se concentration in winter wheat depend on the Se species spiked in the soil and that Rhizophagus intraradices (Ri) significantly enhanced grain Se concentration under selenite treatment. Moreover, inoculation of AMF significantly increased grain Se content under selenite and selenate treatments. The enhanced grain Se content of mycorrhizal wheat could be attributed to (i) apparently increased root growth of mycorrhizal wheat at jointing could absorb more Se for translocating to aerial tissues and consequently result in significantly higher stalk Se content and (ii) enhancing Se translocation from vegetative tissues to grains. The present study showed that AMF significantly (P < 0.05) increased pre-anthesis Se uptake under selenate treatment and post-anthesis Se uptake under selenite treatment. CONCLUSION: The present study indicated the feasibility of inoculation of AMF for increasing grain Se concentration under selenite treatment and enhancing the efficiency of biofortification of Se under selenate treatments. © 2022 Society of Chemical Industry.

Size-dependent transformation, uptake, and transportation of SeNPs in a wheat-soil system.

Foliar application of selenium nanoparticles (SeNPs) has been used to enhance Se concentration in winter wheat, but soil application of SeNPs on Se uptake in the crop and their transformation in soil are still limited. This study investigated the effects of varying sizes (50, 100, 200 nm) and concentrations (0, 2, 5, 25, 100 mg kg-1) of chemical synthesized SeNPs in soil on uptake and accumulation of Se in the crop at maturity and related mechanisms. SeNPs not only posed very low toxic to plant growth, except for leaf, but also significantly enhanced grain Se concentration. Regardless of concentration of SeNPs added to soil, the transformation rate of the larger sized SeNPs (200 nm) in soil was significantly (p < 0.05) higher than that of the smaller one, which is mainly due to the latter was more easily adsorbed onto soil organic matter and reluctant to be oxidized. Significantly higher grain Se concentration under the larger sized SeNPs contributed to significantly higher transformation rate of SeNPs and concentration of available Se in soil. The present study showed that the larger sized SeNPs in soil had significant advantages including higher grain Se concentration and Se utilization efficiency for wheat Se biofortification.

Phase separation at the nanoscale quantified by dcFCCS.

Liquid-liquid phase separation, driven by multivalent macromolecular interactions, causes formation of membraneless compartments, which are biomolecular condensates containing concentrated macromolecules. These condensates are essential in diverse cellular processes. Formation and dynamics of micrometer-scale phase-separated condensates are examined routinely. However, limited by commonly used methods which cannot capture small-sized free-diffusing condensates, the transition process from miscible individual molecules to micrometer-scale condensates is mostly unknown. Herein, with a dual-color fluorescence cross-correlation spectroscopy (dcFCCS) method, we captured formation of nanoscale condensates beyond the detection limit of conventional fluorescence microscopy. In addition, dcFCCS is able to quantify size and growth rate of condensates as well as molecular stoichiometry and binding affinity of client molecules within condensates. The critical concentration to form nanoscale condensates, identified by our experimental measurements and Monte Carlo simulations, is at least several fold lower than the detection limit of conventional fluorescence microscopy. Our results emphasize that, in addition to micrometer-scale condensates, nanoscale condensates are likely to play important roles in various cellular processes and dcFCCS is a simple and powerful quantitative tool to examine them in detail.

Dynamic distribution and accumulation of PAHs in winter wheat during whole plant growth: Field investigation.

A field investigation was conducted to study the dynamic distribution and accumulation of polycyclic aromatic hydrocarbons (PAHs) in winter wheat in the surrounds of a coal-fired power plant. During March to June 2019, various tissues of winter wheat and the corresponding rhizosphere soil were collected for determination of PAHs. A clear spatial downward trend was found in concentration of Σ15PAHs in rhizosphere soil and wheat grain (194-237 µg kg-1 DM) with the increasing distance from the coal-fired power plant. Moreover, Σ15PAHs concentration in rhizosphere soil (1081 µg kg-1 DM), root (464 µg kg-1 DM) and stem (365 µg kg-1 DM) of winter wheat at regreening stage and leaf (323 µg kg-1 DM) at anthesis stage were significantly (p < 0.001) higher than that (895, 432, 287 and 265 µg kg-1 DM) at maturity stage, respectively. From regreening to maturity stage, root concentration factors (RCF) of 3- and 4-ring PAHs exhibited an increasing trend but the 5-ring PAHs showed an apparently downward trend. However, stem concentration factors (SCF) of 3- and 4-ring PAHs showed a decrease trend while the 5- and 6-ring showed first down and then stable trend. There were positive linear relationship between logKow and logSCF at anthesis (r = 0.681, p < 0.05) and maturity stage (r = 0.751, p < 0.05). Based on linear regression analysis, PAHs in grain mainly came from the transfer of vegetative tissues, and the contribution of PAHs from stem and leaf to grain was higher than that from root. In addition, the present study also found that the physicochemical properties of PAHs play a crucial role in transfer of PAHs from root to vegetative tissues and then to grain. The present research provided more comprehensive information on the fate of PAHs in winter wheat and the safety of the agricultural products.

Succession of fungal dynamics and their influence on physicochemical parameters during pig manure composting employing with pine leaf biochar.

The effects of pine leaf biochar (PLB) on fungal community during pig manure composting were investigated. Five different doses of PLB [0% (T1), 2.5% (T2), 5% (T3), 10% (T4) and 15% (T5)] were mixed with mixture of pig manure and sawdust (2:1) for 50 days of composting. The present results indicated that fungal diversity increased more obvious in biochar amendment treatments than control (T1) and that the highest was recorded in T4 treatment. Basidiomycota, Ascomycota and Mucoromycota were the most three abundant phyla in all the treatments, while Heterobasidion, Pezoloma, Mucor, Geastrum, Talaromyces and Cystofilobasidium were the richness genera. In addition, network analysis indicated that fungal community abundance was significantly (p < 0.05) associated with temperature, pH, CO2 and CH4 emission and the seed germination index. In summary, the 10% PLB amendment (T4) was a potential option to strengthen fungal diversity and improve the composting efficiency as well as compost quality.

Impact of pine leaf biochar amendment on bacterial dynamics and correlation of environmental factors during pig manure composting.

The influence of pine leaf biochar (PLB) amendment on bacterial community succession and its correlation with physic-chemical parameters during pig manure (PM) composting was evaluated. The five different dosages of PLB [at 0% (T1), 2.5% (T2), 5% (T3), 10% (T4) and 15% (T5)] mixed with initial composting mass were conducted to composting for 50 days. The present study indicated that bacterial diversity was significantly (p < 0.05) higher in PLB amended treatments than the control, but T4 treatment showed the highest among the all PLB applied treatment. Firmicutes, Actinobacteria, Proteobacteria and Bacteroidete were four most abundant phyla of all the treatments. Furthermore, redundancy analysis showed that the bacterial community were significantly (p < 0.05) positively correlated with temperature, pH, TOC, CO2 and NH3 emissions, while they were negatively correlated with the N2O and CH4 emission. Overall, the results suggested that the addition of 10% PLB (T4 treatment) was a potential option to enhance the composting efficiency with significantly greater abundance of bacterial community and finally improved the compost quality.

Up-regulation of MSH6 is associated with temozolomide resistance in human glioblastoma.

The impact of DNA mismatch repair (MMR) on resistance to temozolomide (TMZ) therapy in patients with glioblastoma (GBM) is recently reported but the mechanisms are not understood. We aim to analyze the correlation between MMR function and the acquired TMZ resistance in GBM using both relevant clinical samples and TMZ resistant cells. First we found increased expression of MSH6, one of key components of MMR, in recurrent GBM patients' samples who underwent TMZ chemotherapy, comparing with those matched samples collected at the time of diagnosis. Using the cellular models of acquired resistance to TMZ, we further confirmed the up-regulation of MSH6 in TMZ resistant cells. Moreover, a TCGA dataset contains a large cohort of GBM clinical samples with or without TMZ treatment reinforced the increased expression of MSH6 and other MMR genes after long-term TMZ chemotherapy, which may resulted in MMR dysfunction and acquired TMZ resistance. Our results suggest that increased expression of MSH6, or other MMR, may be a new mechanism contributing to the acquired resistance during TMZ therapy; and may serve as an indicator to the resistance in GBM.

GFI1 downregulation promotes inflammation-linked metastasis of colorectal cancer.

Inflammation is frequently associated with initiation, progression, and metastasis of colorectal cancer (CRC). Here, we unveil a CRC-specific metastatic programme that is triggered via the transcriptional repressor, GFI1. Using data from a large cohort of clinical samples including inflammatory bowel disease and CRC, and a cellular model of CRC progression mediated by cross-talk between the cancer cell and the inflammatory microenvironment, we identified GFI1 as a gating regulator responsible for a constitutively activated signalling circuit that renders CRC cells competent for metastatic spread. Further analysis of mouse models with metastatic CRC and human clinical specimens reinforced the influence of GFI1 downregulation in promoting CRC metastatic spread. The novel role of GFI1 is uncovered for the first time in a human solid tumour such as CRC. Our results imply that GFI1 is a potential therapeutic target for interfering with inflammation-induced CRC progression and spread.

Neuroprotection by IFN-γ via astrocyte-secreted IL-6 in acute neuroinflammation.

Inflammation eliminates pathogenic infections while also threatening the integrity of the central nervous system. In this study, using in vivo and in vitro models of acute neuroinflammation, we investigated the mechanisms by which inflammation and astrocytes affect neuronal apoptosis. The in vitro model mimicked acute neuroinflammation by incubation in IFN-γ-containing media with primary cultured cerebellar granule neurons, with or without cultured astrocytes. This quickly induced neuronal apoptosis characterized by cleaved caspase-3 expression, Hoechst 33342 staining, and intercellular Ca2+ influx, whereas the presence of astrocytes significantly protected neurons from these effects. IFN-γ in the inflammation media also promoted astrocyte secretion of IL-6, essential for protection. The supernatants of rat peripheral blood mononuclear cells stimulated by lymphocyte mitogen lipopolysaccharide or concanavalin A were used as inflammation media to verify the results. The in vivo model involved a peripheral challenge with lipopolysaccharide, with or without recombinant IFN-γ, in C57BL/6 mice. This confirmed the in vitro results: anti-IFN-γ antibodies exacerbated the acute course of neuroinflammation and led to neurocyte apoptosis in vivo. The pro-inflammatory cytokine IFN-γ provided neuroprotection during acute neuroinflammation via induction of astrocyte-secreted IL-6. The findings provide novel insights into the mechanisms of neuroprotection by IFN-γ during acute neuroinflammation, and may impact therapies for inflammation-related central nervous system injury and disease.

An effective cytokine adjuvant vaccine induces autologous T-cell response against colon cancer in an animal model.

BACKGROUND: Despite recent advances in early detection and improvements in chemotherapy for colon cancer, the patients still face poor prognosis of postoperative recurrence and metastasis, the median survival for patients with metastatic colorectal cancer is approximately 22-24 months. Some immunotherapeutic approaches had been attempted in colon cancer patients to significantly increase overall survival. A vaccine based approach has shown a novel direction for colon cancer prevention and therapy. METHODS: In this study, the experiments were designed including prevention and therapeutic stages in order to attain effect against tumor recurrence in clinical settings. The anti-tumor efficacy of a novel cytokine adjuvant vaccine that contained cytokines GM-CSF and IL-2 and inactivated colon CT26.WT whole cell antigen was evaluated in BALB/c mouse tumor models by measuring tumor growth post vaccination and the survival time of tumor-bearing mice, analyzing the expression and distribution of CD4, CD8, CD11c, CD80, CD86 and CD83 positive cells in control and treated mice by flow cytometry and immunochemistry. The tumor-specific cytotoxic T cells (CTL) were analyzed by tumor proliferation and the lactic dehydrogenates (LDH) release assays. IFN-γ, IL-2 and GM-CSF secretion in serum was assayed by ELISA. RESULTS: Our results suggested that cytokine adjuvant vaccine significantly inhibited tumor growth and extended the survival period at least 160d. It was found that the levels of CD8 + T and the tumor-specific cytotoxicity were significantly higher in prevention and treatment group vaccinated by cytokine adjuvant vaccine. CD8 + T cells play a key role in anti-tumor response. CONCLUSIONS: The novel GM-CSF and IL-2 based adjuvant vaccine effectively activated autologous T-cell response and represented a promising immunotherapeutic approach for patients with colon cancer.

Knockdown of microRNA-195 contributes to protein phosphatase-2A inactivation in rats with chronic brain hypoperfusion.

Reduction of protein phosphatase-2A (PP2A) activity is a common clinical feature of Alzheimer's disease and vascular dementia. In this study, we observed that chronic brain hypoperfusion induced by bilateral common carotid artery occlusion of rats led to PP2A inactivation based on the increase in tyrosine-307 phosphorylation and leucine-309 demethylation of PP2AC and the depression in PP2ABα. Knockdown of miR-195 using overexpression of its antisense molecule oligonucleotide (pre-AMO-miR-195) delivered by a lentivirus (lenti-pre-AMO-miR-195) increased tyrosine-307 phosphorylation and decreased both PP2ABα expression and leucine-309 methylation; these effects were prevented by the overexpression of miR-195 using lenti-pre-miR-195 and controlled by an increase in methylesterase (PME-1) and a decrease in leucine carboxyl methyltransferase-1. In vitro studies demonstrated that miR-195 regulated PME-1 expression by binding to the Ppme1 gene 3'-untranslated region (3'UTR) domain. Masking the miR-195 binding sites in the amyloid precursor protein (APP) and ß-site APP cleaving enzyme 1 genes prevented miR-195-induced leucine carboxyl methyltransferase-1 elevation. We concluded that the miR-195 downregulation in chronic brain hypoperfusion involved PP2A inactivity, which was mediated by the post-transcriptional regulation PME-1, APP, and ß-site APP cleaving enzyme 1 expression.

Nuclear EGFRvIII resists hypoxic microenvironment induced apoptosis via recruiting ERK1/2 nuclear translocation.

Glioblastoma (GBM) is the most aggressive type of primary brain tumor. Its interaction with the tumor microenvironment promotes tumor progression. Furthermore, GBM bearing expression of EGFRvIII displays more adaptation to tumor microenvironment related stress. But the mechanisms were poorly understood. Here, we presented evidence that in the human U87MG glioblastoma tumor model, EGFRvIII overexpression led aberrant kinase activation and nuclear translocation of EGFRvIII/ERK1/2 under hypoxia, which induced growth advantage by resisting apoptosis. Additionally, EGFRvIII defective in nuclear entry impaired this capacity in hypoxia adaptation, and partially interrupted ERK1/2 nuclear translocation. Pharmacology or genetic interference ERK1/2 decreased hypoxia resistance triggered by EGFRvIII expression, but not EGFRvIII nuclear translocation. In summary, this study identified a novel role for EGFRvIII in hypoxia tolerance, supporting an important link between hypoxia and subcellular localization alterations of the receptor.

IRGM1 enhances B16 melanoma cell metastasis through PI3K-Rac1 mediated epithelial mesenchymal transition.

Melanoma is one of the most aggressive skin cancers and is well known for its high metastatic rate. Studies have shown that epithelial mesenchymal transition (EMT) is essential for melanoma cell metastasis. However, the molecular mechanisms underlying EMT are still not fully understood. We have shown that IRGM1, a member of immunity-related GTPase family that regulates immune cell motility, is highly expressed by melanoma cells. The current study aimed to explore whether and how IRGM1 may regulate melanoma cell metastasis. To test this, we modified IRGM1 expression in B16 melanoma cells. We found that over-expression of IRGM1 substantially enhanced pulmonary metastasis in vivo. In keeping with that, knocking-in IRGM1 strongly enhanced while knocking-down IRGM1 impaired B16 cell migration and invasion ability in vitro. Interestingly, we observed that IRGM1 enhanced F-actin polymerization and triggers epithelial mesenchymal transition (EMT) through a mechanism involved in PIK3CA mediated Rac1 activation. Together, these data reveals a novel molecular mechanism that involved in melanoma metastasis.

STAT3 Protein Regulates Vascular Smooth Muscle Cell Phenotypic Switch by Interaction with Myocardin.

The JAK-STAT3 signaling pathway is one of the critical pathways regulating cell proliferation, differentiation, and apoptosis. Myocardin is regarded as a key mediator for the change of smooth muscle phenotypes. However, the relationship between STAT3 and myocardin in the vascular smooth muscle cell (VSMC) phenotypic switch has not been investigated. The goal of this study was to investigate the molecular mechanism by which STAT3 affects the myocardin-regulated VSMC phenotypic switch. Data presented in this study demonstrated that STAT3 was rapidly up-regulated after stimulation with VEGF. Inhibition of the STAT3 activation process impaired VSMC proliferation and enhanced the expression of VSMC contractile genes by increasing serum-response factor binding to the CArG-containing regions of VSMC-specific contractile genes. In contrast, the interaction between serum-response factor and its co-activator myocardin was reduced by overexpression of STAT3. In addition, treated VEGF inhibited the transcription activity of myocardin, and overexpression of STAT3 inhibited myocardin-induced up-regulation of VSMC contractile phenotype-specific genes. Although myocardin and STAT3 are negatively correlated, interestingly, both of them can enhance the expression of VEGF, suggesting a feedback loop to regulate the VSMC phenotypic switch. Taken together, these results indicate that the JAK-STAT3 signaling pathway plays a key role in controlling the phenotypic switch of VSMCs through the interactions between STAT3 and myocardin by various coordinated gene regulation pathways and feedback loops.

MRTF-A and STAT3 promote MDA-MB-231 cell migration via hypermethylating BRSM1.

Breast cancer is the leading cause of cancer death in women worldwide which is closely related to metastasis. But the exact molecular mechanism of metastasis is still not fully understood. We now report that both MRTF-A and STAT3 play important roles in migration of MDA-MB-231 breast cancer cells. Moreover, MRTF-A and STAT3 synergistically increased MDA-MB-231 cell migration by promoting the expression of migration markers urokinase-type plasminogen activator (uPA) and osteopontin (OPN) and inhibiting the expression of breast cancer metastasis suppressor 1 (BRMS1). Luciferase reporter assays demonstrated that MRTF-A and STAT3 do not affect transcription of the BRMS1 promoter. Instead, we identified a newly molecular mechanism by which MRTF-A and STAT3 synergistically controlled MDA-MB-231 cell migration by recruiting DNMT1 to hypermethylate the promoter of BRMS1 and thus affect the expression of BRMS1. Interestingly, physical interaction between MRTF-A and STAT3 synergistically promotes the transactivity of DNMT1 by binding to the GAS element within the DNMT1 promoter. Our data thus provide important and novel insights into the roles of MRTF-A and STAT3 in regulating MDA-MB-231 cell migration.

NF-κB (p65) negatively regulates myocardin-induced cardiomyocyte hypertrophy through multiple mechanisms.

Myocardin is well known to play a key role in the development of cardiomyocyte hypertrophy. But the exact molecular mechanism regulating myocardin stability and transactivity to affect cardiomyocyte hypertrophy has not been studied clearly. We now report that NF-κB (p65) can inhibit myocardin-induced cardiomyocyte hypertrophy. Then we explore the molecular mechanism of this response. First, we show that p65 can functionally repress myocardin transcriptional activity and also reduce the protein expression of myocardin. Second, the function of myocardin can be regulated by epigenetic modifications. Myocardin sumoylation is known to transactivate cardiac genes, but whether p65 can inhibit SUMO modification of myocardin is still not clear. Our data show that p65 weakens myocardin transcriptional activity through attenuating SUMO modification of myocardin by SUMO1/PIAS1, thereby impairing myocardin-mediated cardiomyocyte hypertrophy. Furthermore, the expression of myocardin can be regulated by several microRNAs, which play important roles in the development and function of the heart and muscle. We next investigated potential role of miR-1 in cardiac hypotrophy. Our results show that p65 can upregulate the level of miR-1 and miR-1 can decrease protein expression of myocardin in cardiac myocytes. Notably, miR-1 expression is also controlled by myocardin, leading to a feedback loop. These data thus provide important and novel insights into the function that p65 inhibits myocardin-mediated cardiomyocyte hypertrophy by downregulating the expression and SUMO modification of myocardin and enhancing the expression of miR-1.