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Introduction: Anti-inflammatory medications, in particular aspirin, have chemopreventive and anticancer adjuvant effects on specific types of cancers, according to ongoing anti-tumor research. Additionally, efforts have been made to transform Poly(salicylic acid) (PSA) into delivery-related nanocarriers. to transport anticancer medications into nanocarriers. However, tumor cell targeting and tumor selectivity were lacking in the salicylic acid polymer-based nanocarriers, preventing them from performing to their full potential. Objective: The objective of this study is to prepare targeting and reduction-responsive poly pre-drug nanocarriers (HA-ss-PSA NPs) and to investigate the feasibility of delivering adriamycin (DOX) as nanocarriers. Method: The structures of the polymers were confirmed by nuclear magnetic resonance hydrogen spectroscopy (1H-NMR) and infrared spectroscopy (IR); the encapsulation rate and drug loading of DOX-loaded nanoparticles were determined by HPLC; and the anti-tumor effects of the carriers were evaluated by MTT experiments and in vivo experiments. Results: The prepared nanocarriers had uniform particle size distribution. The drug release rate was up to 80% within 48 h in the tumor environment. DOX/HA-ss-PSA NPs showed significant cytostatic effects. In addition, HA-ss-PSA NPs showed significant targeting and inhibition of cell migration in cell uptake and scratch assays. In vivo experiments showed that the prepared carriers had high tumor inhibition rates, good targeting effects on the liver and tumor, and significantly reduced toxicity to other tissues. Conclusion: The prepared HA-ss-PSA NPs could effectively inhibit the growth of HepG2 cells and tumors in vivo, indicating that PSA could be used as a backbone component of a safe and reliable drug delivery system, providing a new strategy for the treatment of liver cancer.

Yes-associated protein (YAP), as a co-activator of transcription factors, is a downstream protein in the Hippo signaling pathway with important functions in cell proliferation, apoptosis, invasion and migration. YAP also plays a key role in the development of CCl4-induced liver fibrosis. However, the mechanism of YAP during hepatic fibrosis progression and reversion is still unclear. Mild liver fibrosis was developed after 4 months of high-fat diet (HFD) stimulation, and we found that the YAP signaling pathway was activated. Here, we aim to reveal whether specific knockout of Yap gene in the liver can improve liver fibrosis induced by insulin resistance (IR) stimulated by HFD, and further explain its specific mechanism. We found that liver-specific Yap gene knockout improved IR-induced liver fibrosis and liver dysfunction, and this mechanism is related to the inhibition of the insulin signal pathway at the FoxO1 level. These findings provide a new insight, and Yap is expected to be a new target to reverse the early stage of liver fibrosis induced by IR.

To evaluate the effectiveness of a mobile application-assisted nurse-led management model in childhood asthma.Studies have shown that a nurse-led asthma management model can improve asthma outcomes. However, the role of a mobile application-assisted nurse-led model in paediatric asthma management has not been studied well.A multi-centre randomized clinical trial.The trial was conducted between March 2017-March 2018. A total of 152 children (6 to 11.9 years old) were enrolled, with 77 children in the experimental group and 75 in the control group. All children received nurse-led asthma management and other routine treatment measures, including inhaled corticosteroids. Meanwhile, a mobile application was used to manage asthma only for children in the experimental group. Primary outcome was frequency of asthma exacerbations. All outcomes were evaluated twice a month for 12 months.Compared with the pre-enrollment period, frequency of asthma exacerbations decreased in the post-enrollment period in the two groups, with a greater decrease in the experimental group. Compared with children in the control group, children in the experimental group had better secondary outcomes, such as improved adherence, higher Childhood Asthma Control Test scores, decreased respiratory tract infections, days of antibiotic use, days of school absence, parental work loss, and medical expenses.A mobile application-assisted nurse-led management model decreased asthma exacerbations and improved secondary outcomes in children with asthma. Further research is needed to verify its validity in larger population samples.Children with asthma benefited from a nurse-led asthma management model when combined with mobile application. This trial suggested that computer and Internet technologies should be incorporated into nurse-led asthma strategy in paediatric asthma management.The current trial was registered online with the Chinese Clinical Trial Registry (registration number: ChiCTR1800016726).目的: 评估协助护理为主的手机应用管理模式在治疗儿童哮喘中的有效性。 背景: 研究证明,以护理为主的哮喘管理模式能够改善哮喘治疗结果。然而,协助护理为主模式的手机应用在儿科哮喘管理中的作用尚未得到很好的研究。 设计: 多中心随机临床试验。 方法: 该试验于2017年三月至2018年三月期间进行。共152名儿童(6 ~ 11.9岁)登记,其中实验组77名,对照组75名。所有儿童均接受由护士主导的哮喘管理以及其他一些常规治疗措施,包括吸入皮质类固醇。同时,手机应用仅用于实验组儿童哮喘的管理。主要结果是哮喘发作的频率。12个月内每月评估两次所有结果。 结果: 与登记之前相比,两组的哮喘发作频率在登记以后均有所下降,而实验组的下降幅度更大。与对照组的孩子相比,实验组的孩子次要结果更好,比如依从性得到了改善、儿童哮喘控制测试分数更高、呼吸道感染减少、使用抗生素天数、缺课天数、父母工作损失和医疗费用等。 结论: 协助护理为主的手机应用管理模式减少了哮喘恶化并改善了儿童哮喘的次要结果。需要进一步研究验证它在更大的群体样本中的有效性。 影响: 配合手机应用时,儿童哮喘受益于护理主导的哮喘管理模式。本次试验表明,应将计算机及互联网技术纳入儿科哮喘管理中以护理为主导的哮喘治疗策略。 试验注册: 目前的试验是在中国临床试验注册网上注册的(注册编号:中国临床试验注册中心编号1800016726)。.

Many intriguing phenomena occur for electrons under strong magnetic fields1,2. Recently, it was shown that an appropriate strain texture in graphene could induce a synthetic gauge field3–6, in which electrons behave as they do in a real magnetic field7–11. This enabled the control of quantum transport by mechanical means and allowed the unreached high-field regime to be explored. Such synthetic gauge fields have been achieved in molecular12 and photonic13 lattices. Here we report an experimental realization of a giant uniform pseudomagnetic field in acoustics by introducing a simple uniaxial deformation to the acoustic graphene. The controllability of our macroscopic platform enables us to observe the acoustic Landau levels in frequency-resolved spectroscopy and their spatial localization in pressure-field distributions. We further visualize the quantum-Hall-like edge states (connected to the zeroth Landau level), which have been elusive owing to the difficulty in creating large-area uniform pseudomagnetic fields5,6. These results, consistent with our full-wave simulations, establish a complete framework for artificial structures under constant pseudomagnetic fields. Our findings may also offer opportunities to manipulate sound in conceptually novel ways. A graphene-like two-dimensional sonic crystal, under uniaxial deformation, experiences a giant uniform pseudomagnetic field. This leads to the quantization of the cyclotron orbits—a kind of acoustic Landau level—that is observed here.

Higher-order topological insulators as an exotic type of topological phases harboring fascinating topological corner or hinge states have attracted extensive attention recently. Dislocations are crystallinity-breaking defects in lattices that cannot be removed by local deformations due to nontrivial real-space topology. It is recently realized that dislocations can be used as a probe for higher-order topology. In this work, we propose a scheme to obtain acoustic dislocation states by introducing screw dislocations into higher-order topological insulators in a Kagome lattice. The topological dislocation states carry nonzero orbital angular momentum, which are locked to their propagation direction. We show that the screw dislocation states exist for both the tight binding model and the waveguide model as long as the system symmetry is preserved. By delicately designing the dislocation core, the dislocation states with selective angular momentum can be shifted into the bulk bandgap. Based on this in-gap dislocation states, filtering of acoustic vortex with a selective angular momentum is well achieved.

A quadrupole topological insulator, being one higher-order topological insulator with nontrivial quadrupole quantization, has been intensely investigated very recently. However, the tight-binding model proposed for such emergent topological insulators demands both positive and negative hopping coefficients, which imposes an obstacle in practical realizations. Here we introduce a feasible approach to design the sign of hopping in acoustics, and construct the first acoustic quadrupole topological insulator that stringently emulates the tight-binding model. The inherent hierarchy quadrupole topology has been experimentally confirmed by detecting the acoustic responses at the bulk, edge and corner of the sample. Potential applications can be anticipated for the topologically robust in-gap states, such as acoustic sensing and energy trapping., This paper was published in PRL: Phys. Rev. Lett. 124, 206601 (2020)

Diabetic nephropathy is one the most serious diabetic microangiopathies, which is the main cause of mortality in diabetic patients. Our research investigated the protective effects of rutin on kidney of the type 1 diabetes mice induced by streptozotocin (STZ). The levels of kidney weight index (KWI), postprandial plasma glucose (PPG), creatinine (Cre), blood urine nitrogen (BUN), the activity of super oxide dismutase (SOD), malondialdehyde (MDA) and glutathione per oxidase (GSH-Px) were all measured. The histological morphology of kidney tissues was observed by hematoxylin-eosin (HE) staining, masson staining and electron microscope. The collagen I (COL-I) and transforming growth factor-β

Dysregulation of hepatic glucose production (HGP) serves as a major underlying mechanism for the pathogenesis of type 2 diabetes mellitus (T2D). The pancreatic hormone glucagon increases, and insulin suppresses HGP, controlling blood glucose homeostasis. The forkhead transcription factor Foxo1 promotes HGP through increasing expression of genes encoding the rate-limiting enzymes responsible for gluconeogenesis. We previously established that insulin suppresses Foxo1 by Akt-mediated phosphorylation of Foxo1 at Ser256 in human hepatocytes. In this study, we found a novel Foxo1 regulatory mechanism by glucagon, which promotes Foxo1 nuclear translocation and stability via cAMP- and protein kinase A (PKA)-dependent phosphorylation of Foxo1 at Ser276. Replacing Foxo1-S276 with alanine (A) or aspartate (D) to block or mimic phosphorylation, respectively, markedly regulates Foxo1 stability and nuclear localization in human hepatocytes. To establish in vivo function of Foxo1-Ser276 phosphorylation in glucose metabolism, we generated Foxo1-S273A and Foxo1-S273D knock-in (KI) mice. The KI mice displayed impaired blood glucose homeostasis, as well as the basal and glucagon-mediated HGP in hepatocytes. Thus, Foxo1-Ser276 is a new target site identified in control of Foxo1 bioactivity and associated metabolic diseases.

Baihe Wuyao decoction (BWD), a prescription of Traditional Chinese Medicines, composed of Lilium brownii var. viridulum Baker.(Lilii Bulbus) and Lindera aggregata (Sims) Kosterm. (Linderae Radix), has been used to treat epigastric pain and superficial gastritis for hundreds of years in China. Recently, some compounds obtained from Lilii Bulbus and Linderae Radix had active effects of hepatic protection or liver fibrosis alleviation. Thus, we aim to evaluate the effects of BWD on treatment of chronic liver injury and liver fibrosis induced by carbon tetrachloride (CClMice were treated with BWD (low, medium and high dose), diammonium glycyrrhizinate or vehicle by oral gavage once daily, simultaneously intraperitoneal injected with a single dose of CClBWD exhibited a good hepatic protection with ameliorating liver histological changes, decreasing serum AST and ALT contents, and reducing hepatic fibrosis with stimulation ECMs (such as Collagen1 and Collagen3) degradation. BWD inhibited hepatic stellate cells (HSCs) activation, promoted matrix metalloproteinase-2 (MMP2), MMP9, and MMP12 while suppressing tissue inhibitors of matrix metalloproteinase-1 (TIMP1) expression, and blocked traditional fibrosis TGF-β1/Smad2/3 signal pathway. Moreover, BWD exhibited anti-inflammation effect proved by the reduction of liver Interleukin-1β (IL-1β), TNF-α, IL-11 mRNA levels and promoted anti-oxidation effects determined by inhibition of liver MDA and iNOS levels while promoting liver SOD and Mn-SOD.BWD ameliorates CCl

Ethnopharmacological relevance Baihe Wuyao decoction (BWD), a prescription of Traditional Chinese Medicines, composed of Lilium brownii var. viridulum Baker.(Lilii Bulbus) and Lindera aggregata (Sims) Kosterm. (Linderae Radix), has been used to treat epigastric pain and superficial gastritis for hundreds of years in China. Recently, some compounds obtained from Lilii Bulbus and Linderae Radix had active effects of hepatic protection or liver fibrosis alleviation. Thus, we aim to evaluate the effects of BWD on treatment of chronic liver injury and liver fibrosis induced by carbon tetrachloride (CCl4) and to elucidate the possible molecular mechanism. Materials and methods Mice were treated with BWD (low, medium and high dose), diammonium glycyrrhizinate or vehicle by oral gavage once daily, simultaneously intraperitoneal injected with a single dose of CCl4 (1 μl/g body weight) twice a week for consecutive 6 weeks. Next, all mice were sacrificed after fasted 12 h, and serums and liver tissues were harvested for analysis. The hepatic injury was detected by serum biomarker assay, including aspartate aminotransferase (AST) and alanine aminotransferase (ALT). The hepatic histology and collagen were illustrated by hematoxylin-eosin staining and Sirius red staining respectively. The antioxidant capacity of liver tissues was evaluated by the contents of superoxide dismutase (SOD) and malondialdehyde (MDA) in liver homogenization. The mRNA gene or protein expressions related to fibrosis, oxidative stress and inflammation molecules were performed by real-time quantitative PCR (RT-PCR) or Western-blot. Results BWD exhibited a good hepatic protection with ameliorating liver histological changes, decreasing serum AST and ALT contents, and reducing hepatic fibrosis with stimulation ECMs (such as Collagen1 and Collagen3) degradation. BWD inhibited hepatic stellate cells (HSCs) activation, promoted matrix metalloproteinase-2 (MMP2), MMP9, and MMP12 while suppressing tissue inhibitors of matrix metalloproteinase-1 (TIMP1) expression, and blocked traditional fibrosis TGF-β1/Smad2/3 signal pathway. Moreover, BWD exhibited anti-inflammation effect proved by the reduction of liver Interleukin-1β (IL-1β), TNF-α, IL-11 mRNA levels and promoted anti-oxidation effects determined by inhibition of liver MDA and iNOS levels while promoting liver SOD and Mn-SOD. Conclusion BWD ameliorates CCl4-induced CLI and liver fibrosis which is correlated to its blocking TGF-β1/Smad2/3 signaling, anti-inflammation, and anti-oxidation effects. BWD, as a small traditional prescription, is a promising treatment for CLI and liver fibrosis through multiple pharmacological targets.

The transcription factor forkhead box O1 (FoxO1) is a key mediator in the insulin signaling pathway and controls multiple physiological functions, including hepatic glucose production (HGP) and pancreatic β-cell function. We previously demonstrated that S256 in human FOXO1 (FOXO1-S256), equivalent to S253 in mouse FoxO1 (FoxO1-S253), is a key phosphorylation site mediating the effect of insulin as a target of protein kinase B on suppression of FOXO1 activity and expression of target genes responsible for gluconeogenesis. Here, we investigated the role of FoxO1-S253 phosphorylation in control of glucose homeostasis in vivo by generating global FoxO1-S253A/A knockin mice, in which FoxO1-S253 alleles were replaced with alanine (A substitution) blocking FoxO1-S253 phosphorylation. FoxO1-S253A/A mice displayed mild increases in feeding blood glucose and insulin levels but decreases in fasting blood glucose and glucagon concentrations, as well as a reduction in the ratio of pancreatic α-cells/β-cells per islet. FoxO1-S253A/A mice exhibited a slight increase in energy expenditure but barely altered food intake and glucose uptake among tissues. Further analyses revealed that FoxO1-S253A/A enhances FoxO1 nuclear localization and promotes the effect of glucagon on HGP. We conclude that dephosphorylation of S253 in FoxO1 may reflect a molecular basis of pancreatic plasticity during the development of insulin resistance.

Background— Heart failure is a leading cause of morbidity and mortality in the USA and is closely associated with diabetes mellitus. The molecular link between diabetes mellitus and heart failure is incompletely understood. We recently demonstrated that insulin receptor substrates 1, 2 (IRS1, 2) are key components of insulin signaling and loss of IRS1 and IRS2 mediates insulin resistance, resulting in metabolic dysregulation and heart failure, which is associated with downstream Akt inactivation and in turn activation of the forkhead transcription factor Foxo1. Methods and Results— To determine the role of Foxo1 in control of heart failure in insulin resistance and diabetes mellitus, we generated mice lacking Foxo1 gene specifically in the heart. Mice lacking both IRS1 and IRS2 in adult hearts exhibited severe heart failure and a remarkable increase in the β-isoform of myosin heavy chain (β-MHC) gene expression, whereas deletion of cardiac Foxo1 gene largely prevented the heart failure and resulted in a decrease in β-MHC expression. The effect of Foxo1 deficiency on rescuing cardiac dysfunction was also observed in db/db mice and high-fat diet mice. Using cultures of primary ventricular cardiomyocytes, we found that Foxo1 interacts with the promoter region of β-MHC and stimulates gene expression, mediating an effect of insulin that suppresses β-MHC expression. Conclusions— Our study suggests that Foxo1 has important roles in promoting diabetic cardiomyopathy and controls β-MHC expression in the development of cardiac dysfunction. Targeting Foxo1 and its regulation will provide novel strategies in preventing metabolic and myocardial dysfunction and influencing MHC plasticity in diabetes mellitus.

The renin–angiotensin system is a major determinant of blood pressure regulation. It consists of a cascade of enzymatic reactions involving 3 components: angiotensinogen, renin, and angiotensin-converting enzyme, which generate angiotensin II as a biologically active product. Angiotensinogen is largely produced in the liver, acting as a major determinant of the circulating renin–angiotensin system, which exerts acute hemodynamic effects on blood pressure regulation. How the expression of angiotensinogen is regulated is not completely understood. Here, we hypothesize that angiotensinogen is regulated by forkhead transcription factor forkhead box class O1 (Foxo1), an insulin-suppressed transcription factor, and thereby controls blood pressure in mice. We generated liver-specific Foxo1 knockout mice, which exhibited a reduction in plasma angiotensinogen and angiotensin II levels and a significant decrease in blood pressure. Using hepatocyte cultures, we demonstrated that overexpression of Foxo1 increased angiotensinogen expression, whereas hepatocytes lacking Foxo1 demonstrated a reduction of angiotensinogen gene expression and partially impaired insulin inhibition on angiotensinogen gene expression. Furthermore, mouse angiotensinogen prompter analysis demonstrated that the angiotensinogen promoter region contains a functional Foxo1-binding site, which is responsible for both Foxo1 stimulation and insulin suppression on the promoter activity. Together, these data demonstrate that Foxo1 regulates hepatic angiotensinogen gene expression and controls plasma angiotensinogen and angiotensin II levels, modulating blood pressure control in mice.

The slowly activating delayed rectifier K+ current (IKs) is one of the main repolarizing currents in the human heart. Evidence has shown that angiotensin II (Ang II) regulates IKs through the protein kinase C (PKC) pathway, but the related results are controversial. This study was designed to identify PKC isoenzymes involved in the regulation of IKs by Ang II and the underlying molecular mechanism. The whole-cell patch-clamp technique was used to record IKs in isolated guinea pig ventricular cardiomyocytes and in human embryonic kidney (HEK) 293 cells co-transfected with human KCNQ1/KCNE1 genes and Ang II type 1 receptor genes. Ang II inhibited IKs in a concentration-dependent manner in native cardiomyocytes. A broad PKC inhibitor Go6983 (not inhibiting PKCe) and a selective cPKC inhibitor Go6976 did not affect the inhibitory action of Ang II. In contrast, the inhibition was significantly attenuated by PKCe-selective peptide inhibitor eV1-2. However, direct activation of PKC by phorbol 12-myristate 13-acetate (PMA) increased the cloned human IKs in HEK293 cells. Similarly, the cPKC peptide activator significantly enhanced the current. In contrast, the PKCe peptide activator inhibited the current. Further evidence showed that PKCe knockdown by siRNA antagonized the Ang II-induced inhibition on KCNQ1/KCNE1 current, whereas knockdown of cPKCs (PKCα and PKCβ) attenuated the potentiation of the current by PMA. Moreover, deletion of four putative phosphorylation sites in the C-terminus of KCNQ1 abolished the action of PMA. Mutation of two putative phosphorylation sites in the N-terminus of KCNQ1 and one site in KCNE1 (S102) blocked the inhibition of Ang II. Our results demonstrate that PKCe isoenzyme mediates the inhibitory action of Ang II on IKs and by phosphorylating distinct sites in KCNQ1/KCNE1, cPKC and PKCe isoenzymes produce the contrary regulatory effects on the channel. These findings have provided new insight into the molecular mechanism underlying the modulation of the KCNQ1/KCNE1 channel.

The related transcriptional enhancer factor-1 (RTEF-1) increases gene transcription of hypoxia-inducible factor 1α (HIF-1α) and enhances angiogenesis in endothelium. Both hypoxia and inflammatory factor TNF-α regulate gene expression of HIF-1α, but how RTEF-1 and TNF-α coordinately regulate HIF-1α gene transcription is unclear. Here, we found that RTEF-1 interacts with p65 subunit of NF-κB, a primary mediator of TNF-α. RTEF-1 increased HIF-1α promoter activity, whereas expression of p65 subunit inhibited the stimulatory effect. By contrast, knockdown of p65 markedly enhanced RTEF-1 stimulation on the HIF-1α promoter activity (7-fold). A physical interaction between RTEF-1 and p65 was confirmed by coimmunoprecipitation experiments in cells and glutathione S-transferase (GST)-pull-down assays. A computational analysis of RTEF-1 crystal structures revealed that a conserved surface of RTEF-1 potentially interacts with p65 via four amino acid residues located at T347, Y349, R351, and Y352. We performed site-directed mutagenesis and GST-pull-down assays and demonstrated that Tyr352 (Y352) in RTEF-1 is a key site for the formation of RTEF-1 and p65-NF-κB complex. An alanine mutation at Y352 of RTEF-1 disrupted the interaction of RTEF-1 with p65. Moreover, expression of RTEF-1 decreased TNF-α-induced HIF-1α promoter activity, IL-1β, and IL-6 mRNA levels in cells; however, the effect of RTEF-1 was largely lost when Y352 was mutated to alanine. These results indicate that RTEF-1 interacts with p65-NF-κB through Y352 and that they antagonize each other for HIF-1α transcriptional activation, suggesting a novel mechanism by which RTEF-1 regulates gene expression, linking hypoxia to inflammation.

Cardiac failure is a major cause of death in patients with type 2 diabetes, but the molecular mechanism that links diabetes to heart failure remains unclear. Insulin resistance is a hallmark of type 2 diabetes, and insulin receptor substrates 1 and 2 (IRS1 and IRS2) are the major insulin-signaling components regulating cellular metabolism and survival. To determine the role of IRS1 and IRS2 in the heart and examine whether hyperinsulinemia causes myocardial insulin resistance and cellular dysfunction via IRS1 and IRS2, we generated heart-specific IRS1 and IRS2 gene double-knockout (H-DKO) mice and liver-specific IRS1 and IRS2 double-knockout (L-DKO) mice. H-DKO mice had reduced ventricular mass; developed cardiac apoptosis, fibrosis, and failure; and showed diminished Akt→forkhead box class O-1 signaling that was accompanied by impaired cardiac metabolic gene expression and reduced ATP content. L-DKO mice had decreased cardiac IRS1 and IRS2 proteins and exhibited features of heart failure, with impaired cardiac energy metabolism gene expression and activation of p38α mitogen-activated protein kinase (p38). Using neonatal rat ventricular cardiomyocytes, we further found that chronic insulin exposure reduced IRS1 and IRS2 proteins and prevented insulin action through activation of p38, revealing a fundamental mechanism of cardiac dysfunction during insulin resistance and type 2 diabetes.

Coxsackievirus B3 (CVB3) is the major pathogen of human viral myocarditis. CVB3 has been found to manipulate and modify the cellular lipid metabolism for viral replication. The cellular AMP-activated protein kinase (AMPK) is a key regulator of multiple metabolic pathways, including lipid metabolism. Here we explore the potential roles AMPK plays in CVB3 infection. We found that AMPK is activated by the viral replication during CVB3 infection in Hela cells and primary myocardial cells. RNA interference mediated inhibition of AMPK could increase the CVB3 replication in cells, indicating that AMPK contributed to restricting the viral replication. Next, we showed that CVB3 replication could be inhibited by several different pharmacological AMPK activators including metformin, A769662 and AICAR. And the constitutively active AMPK mutant (CA-AMPK) could also inhibit the CVB3 replication. Furthermore, we found that CVB3 infection increased the cellular lipid levels and showed that the AMPK agonist AICAR both restricted CVB3 replication and reduced lipid accumulation through inhibiting the lipid synthesis associated gene expression. We further found that CVB3 infection would also induce AMPK activated in vivo. The AMPK agonist metformin, which has been widely used in diabetes therapy, could decrease the viral replication and further protect the mice from myocardial histological and functional changes in CVB3 induced myocarditis, and improve the survival rate of infected mice. Lastly, it was demonstrated that the AICAR-mediated restriction of viral replication could be rescued partially by exogenous palmitate, the first product of fatty acid biosynthesis, demonstrating that AMPK activation restricted CVB3 infection through its inhibition of lipid synthesis. Taken together, these data in the present study suggest a model in which AMPK is activated by CVB3 infection and restricts viral replication by inhibiting the cellular lipid accumulation, and inform a potential novel therapeutic strategy for CVB3-associated diseases.

Heart failure is a leading cause of morbidity and mortality in the USA and is closely associated with diabetes mellitus. The molecular link between diabetes and heart failure is incompletely understood. We recently demonstrated that insulin receptor substrate 1, 2 (IRS1, 2) are key components of insulin signaling and their dysfunction mediates insulin resistance, resulting in metabolic dysregulation and heart failure. Loss of IRS1 and IRS2 is associated with downstream Akt inactivation and in turn activation of the forkhead transcription factor Foxo1. To determine the role of Foxo1 in control of heart failure in insulin resistance and diabetes, we generated mice lacking Foxo1 gene specifically in the heart. Mice lacking both IRS1 and IRS2 in adult hearts exhibited severe heart failure, loss of mitochondria, and a remarkable increase in the β-isoform of myosin heavy chain (β-MHC) gene expression, while deletion of cardiac Foxo1 gene largely prevented the heart failure and the loss of mitochondria, and resulted in a decrease in β-MHC expression. The effect of Foxo1 deficiency on rescuing cardiac dysfunction was also observed in db/db mice and high-fat diet (HFD) mice. Using cultures of primary ventricular cardiomyocytes, we found that Foxo1 interacts with the promoter region of β-MHC and stimulates gene expression, mediating an effect of insulin that suppresses β-MHC expression. Taken together, our study suggests that Foxo1 has important roles in promoting diabetic cardiomyopathy and controls β-MHC expression in development of cardiac dysfunction. Targeting Foxo1 and its regulation will provide novel strategies in preventing metabolic and myocardial dysfunction and influencing MHC plasticity in diabetes mellitus.

A major cause of death in patients with type 2 diabetes is cardiac failure and the molecular mechanism that links diabetes to cardiomyopathy remains unclear. Insulin resistance is a hallmark of type 2 diabetes and intensive insulin therapy on the patients with type 2 diabetes increases the risks of cardiovascular dysfunction. Thus, understanding the mechanisms of insulin actions and resistance, related to cardiac dysfunction, will be critical for development of new strategies treating heart failure in type 2 diabetes. Insulin receptor substrate 1, & 2 (IRS1, IRS2) are major components in insulin signaling pathway regulating metabolism and survival. Here we hypothesized that (1) loss of IRS1 and IRS2 causes heart failure; (2) hyperinsulinemia contributes to loss of IRS1 and IRS2 in type 2 diabetes and promotes cardiac dysfunction; and (3) underlying mechanisms are involved in protein kinase activation. H-DKO mice (Heart Double IRS1 and IRS2 Knock-Out) and L(Liver)-DKO mice were generated using Cre/Loxp system. Cardiac function and ATP content were measured by echocardiograms and ATP assay kit. Protein and gene expressions were detected through western-blot and Q-PCR. Primary cultures of neonatal rat ventricular cardiomyocytes (NRVMs) were prepared from Sprague-Dawley rats with enzymatic method. H-DKO mice reduced ventricular mass, developed cardiac fibrosis and failure, and diminished Akt→Foxo1 signaling accompanied by impaired cardiac metabolic gene expression patterns and reduced ATP content. L-DKO mice decreased cardiac expression of IRS1 and IRS2 proteins with insulin resistance, disrupting cardiac energy metabolism, leading to heart failure and activation of p38α MAPK (p38). Using NRVMs, we demonstrated that hyperinsulinemia degraded IRS1 and IRS2, resulting in insulin resistance and impaired insulin action through activation of p38. In conclusion, myocardial loss of IRS1 and IRS2 causes heart failure and is controlled by p38 during Insulin resistance, revealing a fundamental mechanism of heart failure during insulin resistance and/or type 2 Diabetes Mellitus.

Dysregulation of blood glucose and triglycerides are the major characteristics of type 2 diabetes mellitus. We sought to identify the mechanisms regulating blood glucose and lipid homeostasis. Cell-based studies established that the Foxo forkhead transcription factors Forkhead box O (Foxo)-1, Foxo3, and Foxo4 are inactivated by insulin via a phosphatidylinositol 3-kinase/Akt-dependent pathway, but the role of Foxo transcription factors in the liver in regulating nutrient metabolism is incompletely understood. In this study, we used the Cre/LoxP genetic approach to delete the Foxo1, Foxo3, and Foxo4 genes individually or a combination of two or all in the liver of lean or db/db mice and assessed the role of Foxo inactivation in regulating glucose and lipid homeostasis in vivo. In the lean mice or db/db mice, hepatic deletion of Foxo1, rather than Foxo3 or Foxo4, caused a modest reduction in blood glucose concentrations and barely affected lipid homeostasis. Combined deletion of Foxo1 and Foxo3 decreased blood glucose levels, elevated serum triglyceride and cholesterol concentrations, and increased hepatic lipid secretion and caused hepatosteatosis. Analysis of the liver transcripts established a prominent role of Foxo1 in regulating gene expression of gluconeogenic enzymes and Foxo3 in the expression of lipogenic enzymes. Our findings indicate that Foxo1 and Foxo3 inactivation serves as a potential mechanism by which insulin reduces hepatic glucose production and increases hepatic lipid synthesis and secretion in healthy and diabetic states.