Targeting Ser78 phosphorylation of Hsp27 achieves potent antiviral effects against enterovirus A71 infection.

A positive-sense (+) single-stranded RNA (ssRNA) virus (e.g. enterovirus A71, EV-A71) depends on viral polypeptide translation for initiation of virus replication after entry. We reported that EV-A71 hijacks Hsp27 to induce hnRNP A1 cytosol redistribution to initiate viral protein translation, but the underlying mechanism is still elusive. Here, we show that phosphorylation-deficient Hsp27-3A (Hsp27S15/78/82A) and Hsp27S78A fail to translocate into the nucleus and induce hnRNP A1 cytosol redistribution, while Hsp27S15A and Hsp27S82A display similar effects to the wild type Hsp27. Furthermore, we demonstrate that the viral 2A protease (2Apro) activity is a key factor in regulating Hsp27/hnRNP A1 relocalization. Hsp27S78A dramatically decreases the IRES activity and viral replication, which are partially reduced by Hsp27S82A. However, Hsp27S15A displays the same activity as the wild-type Hsp27. Peptide S78 potently suppresses EV-A71 protein translation and reproduction through blockage of EV-A71-induced Hsp27 phosphorylation and Hsp27/hnRNP A1 relocalization. A point mutation (S78A) on S78 impairs its inhibitory functions on Hsp27/hnRNP A1 relocalization and viral replication. Taken together, we demonstrate the importance of Ser78 phosphorylation of Hsp27 regulated by virus infection in nuclear translocation, hnRNP A1 cytosol relocation, and viral replication, suggesting a new path (such as peptide S78) for target-based antiviral strategy.

Exploration of the mechanism of reinfusion of fresh autologous blood in type 2 diabetes mice to induce macrophage polarization and inhibit erythrocyte damage.

AIMS/INTRODUCTION: Type 2 diabetes triggers an inflammatory response that can damage red blood cells. M2 macrophages have inhibitory effects on inflammation, and play an important role in tissue damage repair and fibrosis. Autologous blood transfusion has the potential to inhibit red blood cell damage by mediating macrophage polarization. MATERIALS AND METHODS: Swiss mice were used to establish a suitable type 2 diabetes model, and autologous blood transfusion was carried out. The mice were killed, the blood of the mice was collected and CD14+ monocytes were sorted. The expression levels of phenotypic molecules CD16, CD32 and CD206 in CD14+ monocytes were analyzed by flow cytometry. The proportion of M1 and M2 macrophages were analyzed by flow cytometry. The Q value, P50 , 2,3-diphosphoglycerate and Na+ -K+ -ATPase of red blood cells were detected. The red blood cell osmotic fragility test analyzed the red blood cell osmotic fragility. Western blot analysis was used to analyze the expression changes of erythrocyte surface membrane proteins or transporters erythrocyte membrane protein band 4.1, sphingosine-1-phosphate, glycolipid transfer protein and signal peptide peptidase-like 2A. RESULTS: Autologous blood transfusion induced a significant increase in the number of macrophages. The state and capacity of blood cells improved with autologous blood transfusion. Reinfusion of fresh autologous blood in type 2 diabetes mice made erythrocytes shrink. The expression of erythrocyte-related proteins proved that the erythrocyte injury in the reinfusion of fresh autologous blood + type 2 diabetes group was significantly reduced. CONCLUSION: The reinfusion of fresh autologous blood into the body of patients with type 2 diabetes can induce macrophage polarization to M2, thereby inhibiting red blood cell damage.

Metabolic alterations upon SARS-CoV-2 infection and potential therapeutic targets against coronavirus infection.

The coronavirus disease 2019 (COVID-19) caused by coronavirus SARS-CoV-2 infection has become a global pandemic due to the high viral transmissibility and pathogenesis, bringing enormous burden to our society. Most patients infected by SARS-CoV-2 are asymptomatic or have mild symptoms. Although only a small proportion of patients progressed to severe COVID-19 with symptoms including acute respiratory distress syndrome (ARDS), disseminated coagulopathy, and cardiovascular disorders, severe COVID-19 is accompanied by high mortality rates with near 7 million deaths. Nowadays, effective therapeutic patterns for severe COVID-19 are still lacking. It has been extensively reported that host metabolism plays essential roles in various physiological processes during virus infection. Many viruses manipulate host metabolism to avoid immunity, facilitate their own replication, or to initiate pathological response. Targeting the interaction between SARS-CoV-2 and host metabolism holds promise for developing therapeutic strategies. In this review, we summarize and discuss recent studies dedicated to uncovering the role of host metabolism during the life cycle of SARS-CoV-2 in aspects of entry, replication, assembly, and pathogenesis with an emphasis on glucose metabolism and lipid metabolism. Microbiota and long COVID-19 are also discussed. Ultimately, we recapitulate metabolism-modulating drugs repurposed for COVID-19 including statins, ASM inhibitors, NSAIDs, Montelukast, omega-3 fatty acids, 2-DG, and metformin.

Exploration of the effect of PUM1/Cripto-1 pathway on ferroptosis by regulating macrophage polarization in allogeneic blood transfused mice.

BACKGROUND: To study the link between macrophage polarization, PUM1/Cripto-1 pathway and ferroptosis in the allogeneic blood transfusion setting. METHODS: This is an exploratory research. The purpose of this study was to investigate the effect of PUM1/Cripto-1 pathway on ferroptosis by regulating macrophage polarization in allogeneic blood transfused mice. Establish in vitro cell models and in vivo rat models. To find out whether PUM1 and Cripto-1 were expressed, RT-qPCR and Western blot analyses were employed. The macrophage polarization markers iNOS, TNF-, IL-1, IL-6, Arg-1, and IL-10 were utilized to identify M1 and M2 macrophages. JC-1 staining was used to detect ATP membrane potential in peripheral blood macrophages. RESULTS: In animal experiments, expression of Cripto-1 was negatively regulated by PUM1 and promoted M1 type polarization of macrophages. Allogeneic blood transfusion assured good state of macrophage mitochondria. Allogeneic blood transfusion inhibited ferroptosis in macrophages by affecting the PUM1/Cripto-1 pathway. In cell experiments, PUM1 regulated Cripto-1 in mouse macrophage RAW264.7. Polarization of RAW264.7 cells was regulated by the PUM1/Cripto-1 pathway. The effect of PUM1/Cripto-1 pathway on macrophage ferroptosis in cell experiments was consistent with that in animal experiments. CONCLUSIONS: In this study, through in vivo cell experiments and in vitro animal experiments, it was successfully proved that PUM1/Cripto-1 pathway affected ferroptosis by regulating macrophage polarization in allogeneic blood transfused mice.

Intraoperative blood auto-transfusion restrained the malignancy of Liver Cancer via regulating functions of tumor cells and Kuffer cells.

The role of IBA in regulating the recovery of liver cancer was investigated using a rat model of liver cancer and an intraoperative blood return model (IBA). SD rats were used to construct the IBA model. Kupffer cells were isolated from liver cancer tissues, and their biological characteristics were analyzed by flow cytometry. Comet assay was used to detect DNA damage in tumor cells; clone formation assay and transwell assay were used to detect tumor cell proliferation and migration ability. Western blot analysis was used to determine the changes in related signaling pathways. After the IBA treatment, the production of KCs was significantly promoted in rat liver cancer tissues, and the expression levels of cell cycle arrest proteins P53, AEN and CDKN1A were also significantly increased. In tumor cells, IBA induced cell cycle arrest and cellular DNA damage in a p53-mediated manner. In addition, the proliferation and migration of cancer cells were also significantly inhibited. Similar to the in vivo data, the expression of TP53, AEN and CDKN1A was also up-regulated. Our study showed that IBA can inhibit the malignant transformation of hepatocellular carcinoma by modulating the function-dependent p53-mediated pathway of tumor cells and KCs.

Regulation of Macrophage Polarization by miR-449a/Cripto-1-PI3K/AKT/NF-κB Signaling Pathway in Allogeneic Transfusion Mice.

In this study, the expression of Cripto-1 and the role of macrophage polarization in immune response after allogeneic transfusion were analyzed by constructing a mouse model of allogeneic transfusion. In order to analyze the effects of miR-449a on the PI3K/AKT/NF-κB signaling pathway and the expression of downstream related regulatory factors under normal and abnormal conditions, we adopt in vitro and in vivo experiments separately. The molecular mechanism of PI3K/AKT/NF-κB signaling pathway was analyzed by blocking or activating gene expression and western blotting. Experiment in vitro has confirmed that inhibition of miR-449a increased the protein expression of Cripto-1. In vivo experiments confirmed that allogeneic transfusion reduced the expression of Cripto-1, which further inhibited NF-κB signaling pathway through AKT/PI3K phosphorylation, regulated macrophage polarization, inhibited M1 polarization of macrophages, promoted M2 polarization, and thus affected immune response of the body.

Suppressing MDSC Infiltration in Tumor Microenvironment Serves as an Option for Treating Ovarian Cancer Metastasis.

It is still a big puzzle how ovarian cancer cells and the tumor microenvironment (TME) attract lymphocytes infiltration for facilitating metastasis, a leading cause of death from gynecological malignancies. Using genome-wide LncRNA microarray assay, here we report that a LncRNA associated with ovarian cancer metastasis (LncOVM) is highly correlated with poor prognosis and survival. LncOVM interacts with and stabilizes PPIP5K2 by suppressing ubiquitinated degradation to promote complement C5 secretion from ovarian cancer cells. The TME-enriched complement C5 attracts myeloid-derived suppressor cells (MDSCs) infiltration in TME to facilitate metastasis. Knockdown of LncOVM or PPIP5K2 inhibits tumor progression in xenograft models. Application of C5aR antibody or inhibitor (CCX168) inhibits MDSC recruitment and restores the suppression of tumorigenesis and metastasis in vivo. Our study reveals that suppression of ovarian cancer metastasis can be achieved by targeting MDSC infiltration in TME through disrupting LncOVM-PPIP5K2-complement axis, providing an option for treating ovarian cancer patients.

Organocatalytic discrimination of non-directing aryl and heteroaryl groups: enantioselective synthesis of bioactive indole-containing triarylmethanes.

Despite the enormous developments in asymmetric catalysis, the basis for asymmetric induction is largely limited to the spatial interaction between the substrate and catalyst. Consequently, asymmetric discrimination between two sterically similar groups remains a challenge. This is particularly formidable for enantiodifferentiation between two aryl groups without a directing group or electronic manipulation. Here we address this challenge by using a robust organocatalytic system leading to excellent enantioselection between aryl and heteroaryl groups. With versatile 2-indole imine methide as the platform, an excellent combination of a superb chiral phosphoric acid and the optimal hydride source provided efficient access to a range of highly enantioenriched indole-containing triarylmethanes. Control experiments and kinetic studies provided important insights into the mechanism. DFT calculations also indicated that while hydrogen bonding is important for activation, the key interaction for discrimination of the two aryl groups is mainly π-π stacking. Preliminary biological studies also demonstrated the great potential of these triarylmethanes for anticancer and antiviral drug development.

The effects of SARS-CoV-2 infection on modulating innate immunity and strategies of combating inflammatory response for COVID-19 therapy.

The global pandemic of COVID-19 has caused huge causality and unquantifiable loss of social wealth. The innate immune response is the first line of defense against SARS-CoV-2 infection. However, strong inflammatory response associated with dysregulation of innate immunity causes severe acute respiratory syndrome (SARS) and death. In this review, we update the current knowledge on how SARS-CoV-2 modulates the host innate immune response for its evasion from host defense and its corresponding pathogenesis caused by cytokine storm. We emphasize Type I interferon response and the strategies of evading innate immune defense used by SARS-CoV-2. We also extensively discuss the cells and their function involved in the innate immune response and inflammatory response, as well as the promises and challenges of drugs targeting excessive inflammation for antiviral treatment. This review would help us to figure out the current challenge questions of SARS-CoV-2 infection on innate immunity and directions for future studies.

Organocatalytic asymmetric formal oxidative coupling for the construction of all-aryl quaternary stereocenters.

A new catalytic asymmetric formal cross dehydrogenative coupling process for the construction of all-aryl quaternary stereocenters is disclosed, which provides access to rarely explored chiral tetraarylmethanes with excellent enantioselectivity. The suitable oxidation conditions and the hydrogen-bond-based organocatalysis have enabled efficient intermolecular C-C bond formation in an overwhelmingly crowded environment under mild conditions. para-Quinone methides bearing an ortho-directing group serve as the key intermediate. The precise loading of DDQ is critical to the high enantioselectivity. The chiral products have also been demonstrated as promising antiviral agents.