A subunit-based influenza/SARS-CoV-2 Omicron combined vaccine induced potent protective immunity in BALB/c mice.

Infection with influenza A virus (IAV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses a significant risk to human life, health, and the global economy. Vaccination is one of the most effective strategies in the fight against infectious viruses. In this study, we, for the first time, have evaluated the immunogenicity and protective effect of an influenza/SARS-CoV-2 Omicron subunit combined vaccine adjuvanted with MF59 and administered to BALB/c mice. Results showed that the combined vaccine induced high levels of IgG, IgG1 , and IgG2a antibodies, as well as influenza A H1N1/California/2009 virus-specific hemagglutination-inhibiting antibodies in BALB/c mice. Moreover, this subunit combined vaccine induced high titers of neutralization antibodies against SARS-CoV-2 Omicron sublineage BA.5 pseudovirus and effectively reduced the viral load of authentic SARS-CoV-2 Omicron sublineage BA.5.2 in the cell culture supernatants. These results suggested that this subunit combined vaccine achieved protective effect against both H1N1 A/California/07/2009 strain and SARS-CoV-2 Omicron BA.5.2 variant. It is therefore expected that this study will establish the scientific foundation for the next-step development of combined vaccines against other strains or variants of IAV and SARS-CoV-2.

Critical Role of miR-130b-5p in Cardiomyocyte Proliferation and Cardiac Repair in Mice After Myocardial Infarction.

Poor proliferative capacity of adult cardiomyocytes is the primary cause of heart failure after myocardial infarction (MI), thus exploring the molecules and mechanisms that promote the proliferation of adult cardiomyocytes is crucially useful for cardiac repair after MI. Here, we found that miR-130b-5p was highly expressed in mouse embryonic and neonatal hearts and able to promote cardiomyocyte proliferation both in vitro and in vivo. Mechanistic studies revealed that miR-130b-5p mainly promoted the cardiomyocyte proliferation through the MAPK-ERK signaling pathway, and the dual-specific phosphatase 6 (Dusp6), a negative regulator of the MAPK-ERK signaling, was the direct target of miR-130b-5p. Moreover, we found that overexpression of miR-130b-5p could promote the proliferation of cardiomyocytes and improve cardiac function in mice after MI. These studies thus revealed the critical role of miR-130b-5p and its targeted MAPK-ERK signaling in the cardiomyocyte proliferation of adult hearts and proved that miR-130b-5p could be a potential target for cardiac repair after MI.

A 3D "sandwich" co-culture system with vascular niche supports mouse embryo development from E3.5 to E7.5 in vitro.

BACKGROUND: Various methods for ex utero culture systems have been explored. However, limitations remain regarding the in vitro culture platforms used before implanting mouse embryos and the normal development of mouse blastocysts in vitro. Furthermore, vascular niche support during mouse embryo development from embryonic day (E) 3.5 to E7.5 is unknown in vitro. METHODS: This study established a three-dimensional (3D) "sandwich" vascular niche culture system with in vitro culture medium (IVCM) using human placenta perivascular stem cells (hPPSCs) and human umbilical vein endothelial cells (hUVECs) as supportive cells (which were seeded into the bottom layer of Matrigel) to test mouse embryos from E3.5 to E7.5 in vitro. The development rates and greatest diameters of mouse embryos from E3.5 to E7.5 were quantitatively determined using SPSS software statistics. Pluripotent markers and embryo transplantation were used to monitor mouse embryo quality and function in vivo. RESULTS: Embryos in the IVCM + Cells (hPPSCs + hUVECs) group showed higher development rates and greater diameters at each stage than those in the IVCM group. Embryos in the IVCM + Cells group cultured to E5.5 morphologically resembled natural egg cylinders and expressed specific embryonic cell markers, including Oct4 and Nanog. These features were similar to those of embryos developed in vivo. After transplantation, the embryos were re-implanted in the internal uterus and continued to develop to a particular stage. CONCLUSIONS: The 3D in vitro culture system enabled embryo development from E3.5 to E7.5, and the vascularization microenvironment constructed by Matrigel, hPPSCs, and hUVECs significantly promoted the development of implanted embryos. This system allowed us to further study the physical and molecular mechanisms of embryo implantation in vitro.

Cooperative regulation of Zhx1 and hnRNPA1 drives the cardiac progenitor-specific transcriptional activation during cardiomyocyte differentiation.

The zinc finger proteins (ZNFs) mediated transcriptional regulation is critical for cell fate transition. However, it is still unclear how the ZNFs realize their specific regulatory roles in the stage-specific determination of cardiomyocyte differentiation. Here, we reported that the zinc fingers and homeoboxes 1 (Zhx1) protein, transiently expressed during the cell fate transition from mesoderm to cardiac progenitors, was indispensable for the proper cardiomyocyte differentiation of mouse and human embryonic stem cells. Moreover, Zhx1 majorly promoted the specification of cardiac progenitors via interacting with hnRNPA1 and co-activated the transcription of a wide range of genes. In-depth mechanistic studies showed that Zhx1 was bound with hnRNPA1 by the amino acid residues (Thr111-His120) of the second Znf domain, thus participating in the formation of cardiac progenitors. Together, our study highlights the unrevealed interaction of Zhx1/hnRNPA1 for activating gene transcription during cardiac progenitor specification and also provides new evidence for the specificity of cell fate determination in cardiomyocyte differentiation.

Neonatal Plasma Exosomes Contribute to Endothelial Cell-Mediated Angiogenesis and Cardiac Repair after Acute Myocardial Infarction.

Acute myocardial infarction (AMI) accompanied by cardiac remodeling still lacks effective treatment to date. Accumulated evidences suggest that exosomes from various sources play a cardioprotective and regenerative role in heart repair, but their effects and mechanisms remain intricate. Here, we found that intramyocardial delivery of plasma exosomes from neonatal mice (npEXO) could help to repair the adult heart in structure and function after AMI. In-depth proteome and single-cell transcriptome analyses suggested that npEXO ligands were majorly received by cardiac endothelial cells (ECs), and npEXO-mediated angiogenesis might serve as a pivotal reason to ameliorate the infarcted adult heart. We then innovatively constructed systematical communication networks among exosomal ligands and cardiac ECs and the final 48 ligand-receptor pairs contained 28 npEXO ligands (including the angiogenic factors, Clu and Hspg2), which mainly mediated the pro-angiogenic effect of npEXO by recognizing five cardiac EC receptors (Kdr, Scarb1, Cd36, etc.). Together, the proposed ligand-receptor network in our study might provide inspiration for rebuilding the vascular network and cardiac regeneration post-MI.

MiR-181a-5p promotes neural stem cell proliferation and enhances the learning and memory of aged mice.

Hippocampal neural stem cell (NSC) proliferation is known to decline with age, which is closely linked to learning and memory impairments. In the current study, we found that the expression level of miR-181a-5p was decreased in the hippocampal NSCs of aged mice and that exogenous overexpression of miR-181a-5p promoted NSC proliferation without affecting NSC differentiation into neurons and astrocytes. The mechanistic study revealed that phosphatase and tensin homolog (PTEN), a negative regulator of the AKT signaling pathway, was the target of miR-181a-5p and knockdown of PTEN could rescue the impairment of NSC proliferation caused by low miR-181a-5p levels. Moreover, overexpression of miR-181a-5p in the dentate gyrus enhanced the proliferation of NSCs and ameliorated learning and memory impairments in aged mice. Taken together, our findings indicated that miR-181a-5p played a functional role in NSC proliferation and aging-related, hippocampus-dependent learning and memory impairments.

Chemical profile of anti-epidemic sachet based on multiple sample preparation coupled with gas chromatography-mass spectrometry analysis combined with an embedded peaks resolution method and their action mechanisms.

The anti-epidemic sachet (Fang Yi Xiang Nang, FYXN) in traditional Chinese medicine (TCM) can prevent COVID-19 through volatile compounds that can play the role of fragrant and dampness, heat-clearing and detoxifying, warding off filth and pathogenic factors. Nevertheless, the anti-(mutant) SARS-CoV-2 compounds and the compounds related to the mechanism in vivo, and the mechanism of FYXN are still vague. In this study, the volatile compound set of FYXN was constructed by gas chromatography-mass spectrometry (GC-MS) based on multiple sample preparation methods, which include headspace (HS), headspace solid phase microextraction (HS-SPME) and pressurized liquid extraction (PLE). In addition, selective ion analysis (SIA) was used to resolve embedded chromatographic peaks present in HS-SPME results. Preliminary analysis of active compounds and mechanism of FYXN by network pharmacology combined with disease pathway information based on GC-MS results. A total of 96 volatile compounds in FYXN were collected by GC-MS analysis. 39 potential anti-viral compounds were screened by molecular docking. 13 key pathways were obtained by KEGG pathway analysis (PI3K-Akt signaling pathway, HIF-1 signaling pathway, etc.) for FYXN to prevent COVID-19. 16 anti-viral compounds (C95, C91, etc.), 10 core targets (RELA, MAPK1, etc.), and 16 key compounds related to the mechanism in vivo (C56, C30, etc.) were obtained by network analysis. The relevant pharmacological effects of key pathways and key compounds were verified by the literature. Finally, molecular docking was used to verify the relationship between core targets and key compounds, which are related to the mechanism in vivo. A variety of sample preparation methods coupled with GC-MS analysis combined with an embedded peaks resolution method and integrated with network pharmacology can not only comprehensively characterize the volatile compounds in FYXN, but also expand the network pharmacology research ideas, and help to discover the active compounds and mechanisms in FYXN.

Ferruginivarius sediminum gen. nov., sp. nov., isolated from a marine solar saltern.

A novel Gram-stain-negative, facultatively anaerobic, oxidase-negative, catalase-positive bacillus, designated WD2A32T, was isolated from a marine solar saltern in the coast of Weihai, Shandong Province, PR China. Strain WD2A32T grew optimally at 37-40 °C (range, 20-45 °C) and pH 7.0-7.5 (range, 6.5-8.0) and was tolerant to 6-8 % (w/v) NaCl (range, 2-12 %). The 16S rDNA of strain WD2A32T was most similar (93.5 %) to that of Rhodovibrio salinarumDSM 9154T (the type species of the genus Rhodovibrio), followed by Limimonas halophilaDSM 25584T (92.4 %; the type species of the genus Limimonas). The similarities to the type strains of the genera Pelagibiusand Limibacilluswere less than 91.0 %. The draft genome sequence of strain WD2A32T contained 72 contigs (>507 bp) of 4 237 996 bp with a DNA G+C content of 65.5 mol%. The major polar lipids of strain WD2A32T were phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine and unidentified aminolipids; major cellular fatty acids were summed feature 8 (C18 : 1ω7c/C18 : 1ω6c) and C19 : 0 cyclo ω8c; the major respiratory quinone was Q-10. On the basis of the results from chemotaxonomic, physiological and biochemical analyses, strain WD2A32T represents a novel species of a novel genus in the family Rhodospirillaceae, for which the name Ferruginivarius sediminum gen. nov., sp. nov. has been proposed. The type strain is WD2A32T (=KCTC 52888T=MCCC 1H00201T).