A carbothermic hybrid synthesized using waste halogenated plastic in sub/supercritical CO2 and its application for lithium recovery.

Facile fabrication of porous carbon materials from waste halogenated plastic is highly attractive but frequently hampered due to potential release of halogenated organic pollutants. In this study, a novel type of carbon hybrid was tentatively synthesized from a real-world halogenated plastic as an inexpensive carbon source by sub/supercritical carbon dioxide carbonization technique. It was found that halogen-free carbon carrier was advantageously synthesized through carbonization of halogenated plastic without using catalysts due to zip depolymerization, random chain cracking and free radical reactions induced by sub/supercritical carbon dioxide technique. Exhibiting with more abundant functional groups including C-O, CO groups than pyrolytic carbon carrier, the derived carbon carrier demonstrated excellent performance in selective recovery of lithium from cathode powder with highest recovery efficiency of 93.6%. Mechanism study indicated that cathode powder was transformed into low-valence states of transition metals/metal oxides and released lithium as lithium carbonate due to collapse of oxygen framework via carbothermic reduction. This work provides an applicable and green process for synthesis of alternative carbon carrier from waste halogenated plastic and its application as carbothermic reductant in lithium recovery.

Biology activity and characterization of the functional L-HN fragment derivative of botulinum neurotoxin serotype E.

OBJECTIVES: The mature botulinum neurotoxin (BoNT) is a long peptide chain consisting of a light chain (L) and a heavy chain (H) linked by a disulfide bond, where the heavy chain is divided into a translocation domain and an acceptor binding domain (Hc). In this study, we further explored the biology activity and characteristics of recombinant L-HN fragment (EL-HN) composed of the L and HN domains of BoNT/E in vivo and in vitro. METHODS: Neurotoxicity of L-HN fragments from botulinum neurotoxins was assessed in mice. Cleavage of dichain EL-HN in vitro and in neuro-2a cells was assessed and compared with that of single chain EL-HN. Interaction of HN domain and the receptor synaptic vesicle glycoprotein 2C (SV2C) was explored in vitro and in neuro-2a cells only expressing SV2C. RESULTS: We found that the 50% mouse lethal dose of the nicked dichain EL-HN fragment (EL-HN-DC) was 0.5 µg and its neurotoxicity was the highest among the L-HN's of the four serotypes of BoNT (A/B/E/F). The cleavage efficiency of EL-HN-DC toward synaptosome associated protein 25 (SNAP25) in vitro was 3-fold higher than that of the single chain at the cellular level, and showed 200-fold higher animal toxicity. The EL-HN-DC fragment might enter neuro-2a cells via binding to SV2C to efficiently cleave SNAP25. CONCLUSIONS: The EL-HN fragment showed good biological activities in vivo and in vitro, and could be used as a drug screening model and to further explore the molecular mechanism of its transmembrane transport.

Physical Fields Manipulation for High-Performance Perovskite Photovoltaics.

With the efforts of researchers from all over the world, metal halide perovskite solar cells (PSCs) have been booming rapidly in recent years. Generally, perovskite films are sensitive to surrounding conditions and will be changed under the action of physical fields, resulting in lattice distortion, degradation, ion migration, and so on. In this review, the progress of physical fields manipulation in PSCs, including the electric field, magnetic field, light field, stress field, and thermal field are reviewed. On this basis, the influences of these fields on PSCs are summarized and prospected. Finally, challenges and prospective research directions on how to make better use of external-fields while minimizing the unnecessary and disruptive impacts on commercial PSCs with high-efficiency and steady output are proposed.

Clinical significance of intracavitary electrocardiographic localization in the prevention of PICC heterotopia in children with tumor.

OBJECTIVE: To explore the clinical significance of intracavitary electrocardiogram positioning technology in preventing catheter ectopic position during peripherally inserted central catheter (PICC) catheterization in children with tumors. METHODS: A retrospective analysis of the clinical data of 62 children who required PICC catheterization was performed. The intracavitary electrocardiogram (ECG) positioning technology was used during the tube placement of the child patients. After the tube was successfully placed, the chest radiograph was taken. The ECG positioning result was compared with the chest radiograph positioning result after the tube was inserted, and the sensitivity and specificity of the ECG positioning were calculated. RESULTS: The intracavitary electrocardiogram results of 62 children with PICC catheters showed that 56 cases (90.32%) had characteristic P waves, and six cases (9.68%) had no characteristic P waves. The chest radiographs of 56 children with characteristic P wave showed that 33 cases (58.93%) of the catheter tip position was appropriate, 22 cases (39.29%) of the catheter tip was too deep, and 1 case was in a non-superior vena cava; six cases of chest radiographs of children with no characteristic P wave showed: one case was too deep at T8 level, one case was too shallow at T4 level, four cases were at non-superior vena cava, one case was contralateral internal jugular vein, two cases in the contralateral brachiocephalic vein, and one case was the contralateral subclavian vein. CONCLUSION: Intracavitary ECG positioning assisted catheter placement in infants can effectively improve the accuracy of catheter tip position.

Mitochondrial aconitase controls adipogenesis through mediation of cellular ATP production.

Mitochondrial aconitase (Aco2) catalyzes the conversion of citrate to isocitrate in the TCA cycle, which produces NADH and FADH2, driving synthesis of ATP through OXPHOS. In this study, to explore the relationship between adipogenesis and mitochondrial energy metabolism, we hypothesize that Aco2 may play a key role in the lipid synthesis. Here, we show that overexpression of Aco2 in 3T3-L1 cells significantly increased lipogenesis and adipogenesis, accompanied by elevated mitochondrial biogenesis and ATP production. However, when ATP is depleted by rotenone, an inhibitor of the respiratory chain, the promotive role of Aco2 in adipogenesis is abolished. In contrast to Aco2 overexpression, deficiency of Aco2 markedly reduced lipogenesis and adipogenesis, along with the decreased mitochondrial biogenesis and ATP production. Supplementation of isocitrate efficiently rescued the inhibitory effect of Aco2 deficiency. Similarly, the restorative effect of isocitrate was abolished in the presence of rotenone. Together, these results show that Aco2 sustains normal adipogenesis through mediating ATP production, revealing a potential mechanistic link between TCA cycle enzyme and lipid synthesis. Our work suggest that regulation of adipose tissue mitochondria function may be a potential way for combating abnormal adipogenesis related diseases such as obesity and lipodystrophy.

Enantioselective decarboxylative Mannich reaction of ß-keto acids with C-alkynyl N-Boc N,O-acetals: access to chiral ß-keto propargylamines.

The chiral keto-substituted propargylamines are an essential class of multifunctional compounds in the field of organic and pharmaceutical synthesis and have attracted considerable attention, but the related synthetic approaches remain limited. Therefore, a concise and efficient method for the enantioselective synthesis of ß-keto propargylamines via chiral phosphoric acid-catalyzed asymmetric Mannich reaction between ß-keto acids and C-alkynyl N-Boc N,O-acetals as easily available C-alkynyl imine precursors has been demonstrated here, affording a broad scope of ß-keto N-Boc-propargylamines in high yields (up to 97%) with generally high enantioselectivities (up to 97 : 3 er).

[Arachidonic acid Alox15/12-HETE signaling inhibits vascular calcification].

This study aims to explore the effects of arachidonic acid lipoxygenase metabolism in vascular calcification. We used 5/6 nephrectomy and high-phosphorus feeding to establish a model of vascular calcification in mice. Six weeks after nephrectomy surgery, vascular calcium content was measured, and Alizarin Red S and Von Kossa staining were applied to detect calcium deposition in aortic arch. Control aortas and calcified aortas were collected for mass spectrometry detection of arachidonic acid metabolites, and active molecules in lipoxygenase pathway were analyzed. Real-time quantitative PCR was used to detect changes in the expression of lipoxygenase in calcified aortas. Lipoxygenase inhibitor was used to clarify the effect of lipoxygenase metabolic pathways on vascular calcification. The results showed that 6 weeks after nephrectomy surgery, the aortic calcium content of the surgery group was significantly higher than that of the sham group (P < 0.05). Alizarin Red S staining and Von Kossa staining showed obvious calcium deposition in aortic arch from surgery group, indicating formation of vascular calcification. Nine arachidonic acid lipoxygenase metabolites were quantitated using liquid chromatography/mass spectrometry (LC-MS) analysis. The content of multiple metabolites (12-HETE, 11-HETE, 15-HETE, etc.) was significantly increased in calcified aortas, and the most abundant and up-regulated metabolite was 12-HETE. Furthermore, we examined the mRNA levels of metabolic enzymes that produce 12-HETE in calcified blood vessels and found the expression of arachidonate lipoxygenase-15 (Alox15) was increased. Blocking Alox15/12-HETE by Alox15 specific inhibitor PD146176 significantly decreased the plasma 12-HETE content, promoted calcium deposition in aortic arch and increased vascular calcium content. These results suggest that the metabolism of arachidonic acid lipoxygenase is activated in calcified aorta, and the Alox15/12-HETE signaling pathway may play a protective role in vascular calcification.

[Effect of arachidonic acid cytochrome P450ω hydroxylase Cyp4a14 gene knockout on skeletal muscle regeneration after injury].

The objective of this study was to explore the roles of arachidonic acid cytochrome P450ω hydroxylase CYP4A14 in skeletal muscle regeneration after injury. Wild-type (WT) control mice and Cyp4a14 knockout (A14-/-) mice were used to establish the muscle injury and regeneration model by intramuscular injection with cardiotoxin (CTX) on the tibial anterior (TA) muscle. The TA muscles were harvested at the time points of 0, 3, 5 and 15 days after injury. The changes in skeletal muscle regeneration and fibrosis were assessed by wheat germ agglutinin (WGA) staining and Sirius Red staining. Immunohistochemical staining was used to observe the expression of proliferation-related protein Ki-67 and macrophage marker protein Mac-2. The mRNA levels of regeneration and inflammation associated genes were analyzed by real-time PCR. The results showed that the cross-section area (CSA) of regenerated myofibers in A14-/- mice was significantly smaller (P < 0.05), while the percentage of fibrosis area was significantly higher than those in WT mice at 15 days after injury (P < 0.05). In A14-/- muscles, both the ratio of Ki-67 positive proliferating cells and the mRNA levels of differentiation associated genes Myod1 and Myog were significantly lower than those in WT muscles (P < 0.05). At 3 days after injury, the mRNA expression of inflammatory cells marker genes CD45 and CD11b and Mac-2 positive macrophages in A14-/- muscles were significantly lower than those in WT skeletal muscle (P < 0.05). Macrophages derived pro-regeneration cytokines IL-1ß, IGF-1 and SDF-1 were also significantly decreased in A14-/- muscles (P < 0.05). These results suggest that arachidonic acid cytochrome P450ω hydroxylase CYP4A14 plays a critical role in skeletal muscle regeneration after injury.

Theory of Chiral p-Wave Superconductivity with Near Nodes for Sr_{2}RuO_{4}.

We use the functional renormalization group method to study a three-orbital model for superconducting Sr_{2}RuO_{4}. Although the pairing symmetry is found to be a chiral p wave, the atomic spin-orbit coupling induces near nodes for quasiparticle excitations. Our theory explains a major experimental puzzle between a d-wavelike feature observed in thermal experiments and the chiral p-wave triplet pairing revealed in nuclear-magnetic resonance and the Kerr effect.

Complement 5a stimulates macrophage polarization and contributes to tumor metastases of colon cancer.

Inflammatory cells such as macrophages can play a pro-tumorigenic role in the tumor stroma. Tumor-associated macrophages (TAMs) generally display an M2 phenotype with tumor-promoting activity; however, the mechanisms regulating the TAM phenotype remain unclear. Complement 5a (C5a) is a cytokine-like polypeptide that is generated during complement system activation and is known to promote tumor growth. Herein, we investigated the role of C5a on macrophage polarization in colon cancer metastasis in mice. We found that deficiency of the C5a receptor (C5aR) severely impairs the metastatic ability of implanted colon cancer cells. C5aR was expressed on TAMs, which exhibited an M2-like functional profile in colon cancer liver metastatic lesions. Furthermore, C5a mediated macrophage polarization and this process relied substantially on activation of the nuclear factor-kappa B (NF-κB) pathway. Finally, analysis of human colon carcinoma indicated that C5aR expression is negatively associated with tumor differentiation grade. Our results demonstrate that C5aR has a central role in regulating the M2 phenotype of TAMs, which in turn, contributes to hepatic metastasis of colon cancer through NF-κB signaling. C5a is a potential novel marker for cancer prognosis and drugs targeting complement system activation, specifically the C5aR pathway, may offer new therapeutic opportunities for colon cancer management.

IL-18 cleavage triggers cardiac inflammation and fibrosis upon ß-adrenergic insult.

Aims: Rapid over-activation of ß-adrenergic receptor (ß-AR) upon stress leads to cardiac inflammation, a prevailing factor that underlies heart injury. However, mechanisms by which acute ß-AR stimulation induce cardiac inflammation still remain unknown. Here, we set out to identify the crucial role of inflammasome/interleukin (IL)-18 in initiating and maintaining cardiac inflammatory cascades upon ß-AR insult. Methods and results: Male C57BL/6 mice were injected with a single dose of ß-AR agonist, isoproterenol (ISO, 5 mg/kg body weight) or saline subcutaneously. Cytokine array profiling demonstrated that chemokines dominated the initial cytokines upregulation specifically within the heart upon ß-AR insult, which promoted early macrophage infiltration. Further investigation revealed that the rapid inflammasome-dependent activation of IL-18, but not IL-1ß, was the critical up-stream regulator for elevated chemokine expression in the myocardium upon ISO induced ß1-AR-ROS signalling. Indeed, a positive correlation was observed between the serum levels of norepinephrine and IL-18 in patients with chest pain. Genetic deletion of IL-18 or the up-stream inflammasome component NLRP3 significantly attenuated ISO-induced chemokine expression and macrophage infiltration. In addition, IL-18 neutralizing antibodies selectively abated ISO-induced chemokines, proinflammatory cytokines and adhesion molecules but not growth factors. Moreover, blocking IL-18 early after ISO treatment effectively attenuated cardiac inflammation and fibrosis. Conclusion: Inflammasome-dependent activation of IL-18 within the myocardium upon acute ß-AR over-activation triggers cytokine cascades, macrophage infiltration and pathological cardiac remodelling. Blocking IL-18 at the early stage of ß-AR insult can successfully prevent inflammatory responses and cardiac injuries.

[Role of TRPC6 in pulmonary artery smooth muscle cells proliferation and apoptosis under hypoxia and hypercapnia].

The present study was to investigate the role of TRPC6 in pulmonary artery smooth muscle cells (PASMCs) proliferation and apoptosis under hypoxia and hypercapnia. PASMCs were isolated from chloral hydrate-anesthetized male Sprague-Dawley (SD) rats. Cellular purity was assessed by immunofluorescence staining for smooth muscle α-actin under fluorescence microscopy. Passage 4-6 PASMCs were starved for 24 h in serum-free DMEM and divided into 5 groups randomly: normoxia, hypoxia and hypercapnia, DMSO, TRPC6 inhibitor SKF-96365 and TRPC6 activator OAG groups. The normoxic group was incubated under normoxia (5% CO2, 21% O2, 37 °C) for 24 h, and the others were incubated with corresponding drugs under hypoxic and hypercapnic (6% CO2, 5% O2, 37 °C) atmosphere for 24 h. TRPC6 mRNA was detected by reverse transcription-PCR. TRPC6 protein was detected by Western blotting. The proliferation of PASMCs was performed by CCK-8 kit. Apoptosis of the PASMCs was detected using TUNEL assay. The [Ca2+]i in the PASMCs was measured using Fura 2-AM fluorescence. The results showed that the expressions of TRPC6 mRNA and protein, and [Ca2+]i were upregulated under hypoxic and hypercapnic conditions. Hypoxia and hypercapnia promoted cellular proliferation and inhibited apoptosis in the PASMCs. OAG enhanced the above-mentioned effects of hypoxia and hypercapnia, whereas SKF-96365 reversed these effects. These results suggest that TRPC6 may play a role in PASMCs proliferation and apoptosis under hypoxia and hypercapnia by regulating [Ca2+]i.

Cross talk between vascular smooth muscle cells and monocytes through interleukin-1ß/interleukin-18 signaling promotes vein graft thickening.

OBJECTIVE: Interleukin (IL)-1ß and IL-18 are key proinflammatory cytokines that play important roles in the pathophysiology of vein graft remodeling. However, the mechanism of IL-1ß/IL-18 production and its role in the development of graft remodeling remain unclear. APPROACH AND RESULTS: IL-1ß/IL-18 were rapidly expressed in venous interposition grafts. Vascular smooth muscle cell (VSMC) death and monocytic inflammasome activation occurred in grafted veins. Necrotic VSMCs induced the expression of IL-1ß, IL-18, and other inflammasome-associated proteins in monocytes, which was partially inhibited by their antagonist, recombinant IL-1ra-Fc-IL-18bp. Activated monocytes stimulated proliferation of VSMCs by activating cell growth-related signaling molecules (AKT, STAT3, ERK1/2, and mTOR [AKT/protein kinase B, signal transducer and activator of transcription 3, extracellular signal-regulated kinase 1/2, mammalian target of rapamycin]) and increasing production of platelet-derived growth factor-bb; these effects were suppressed by IL-1ra-Fc-IL-18bp. Activated monocytes also promoted migration of VSMCs, which was independent of IL-1ß/IL-18 signaling. Importantly, administration of IL-1ra-Fc-IL-18bp inhibited activation of cell growth-related signaling molecules, VSMC proliferation, and vein graft thickening in vivo. CONCLUSIONS: Our work identified an interaction among necrotic VSMCs, monocytes, and viable VSMCs through IL-1ß/IL-18 signaling, which might be exploited as a therapeutic target in vein graft remodeling.

[Application of high-content screening and flow cytometry analysis techniques to evaluation of myocardial fibroblasts proliferation].

The proliferation of cardiac fibroblasts (CFs) is a key pathological process in the cardiac remodeling. To establish an objective, quantitative method for the analysis of cell proliferation and cell cycle, we applied the high-content screening (HCS) and flow cytometry (FCM) techniques. CFs, isolated by enzyme digestion from newborn C57BL/6J mice, were serum starved for 12 h and then given 10% fetal bovine serum (FBS) for 24 h. Followed by BrdU and DAPI (or 7-AAD) staining, CFs proliferation and cell cycle were analyzed by HCS and FCM, respectively. Discoidin domain receptor 2 (DDR2) staining indicated that the purity of isolated CFs was over 95%. (1) HCS analysis showed that the ratio of BrdU-positive cells was significantly increased in 10% FBS treated group compared with that in serum-free control group [(12.96 ± 0.67)% vs (2.77 ± 0.33)%; P < 0.05]. Cell cycle analysis showed that CFs in G0/G1 phase were diploid, and CFs in S phase were companied with proliferation, DNA replication and enlarged nuclei; CFs in G2 phase were tetraploid, and CFs in M phase produced two identical cells (2N). (2) FCM analysis showed that the ratio of BrdU-positive cells was increased in 10% FBS treated group compared with that in the control group [(11.10 ± 0.42)% vs (2.22 ± 0.31)%; P < 0.05]; DNA content histogram of cell cycle analysis indicated that the platform of S phase elevated in 10% FBS group compared with control group. (3) There were no differences between the two methods in the results of proliferation and cell cycle analysis. In conclusion, HCS and FCM methods are reliable, stable and consistent in assessment of the proliferation and cell cycle in CFs.

[Effect of zige lyophilized powder for injection in improving acute cerebral microcirculation disturbance in rats].

OBJECTIVE: To investigate the effect of Zige lyophilized powder for injection in improving the acute cerebral microcirculation disturbance in rats. METHOD: Window craniotomy was performed for rats after the drug administration for 14 days. The experimental microcirculation disturbance model was duplicated with high molecule dextran. After the drug administration, the micro-vein diameters of cerebral pla mater of various groups were observed and recorded under the biological microscope. The blood flow volume was monitored by laser Doppler flow-meter. HCT was measured by the electric resistance method. The hemorheological indexes were detected by the auto-hemorheological instrument. RESULT: Zige lyophilized powder for injection (16.40, 32.70, 65.40 mg x kg(-1)) could significantly expand the micro-vein diameter of cerebral pla mater, improve the downward trend of the blood flow volume, and reduce the various hemorheological indexes. CONCLUSION: Zige lyophilized powder for injection shows the effect in improving the cerebral microcirculation.

Conversion and fate of waste Li-ion battery electrolyte in a two-stage thermal treatment process.

Disposal of electrolytes from waste lithium-ion batteries (LIBs) has gained much more attention with the growing application of LIBs, yet handling spent electrolyte is challengeable due to its high toxicity and the lack of established methods. In this study, a novel two-stage thermal process was developed for treating residual electrolytes resulted from spent lithium-ion batteries. The conversion of fluorophosphate and organic matter in oily electrolyte during low-temperature rotation distillation was investigated. The distribution and migration of the concentrated electrolytes were studied and the corresponding reaction mechanisms were elucidated. Additionally, the influence of alkali on the fixation of fluorine and phosphate was further examined. The results indicated that hydrolyzed carbonate esters and lithium in the electrolyte could combine to form Li2CO3 and the hydrolysable hexafluorophosphate was proven to be stable in the concentrated electrolyte (45 rpm/85 °C, 30 min). It was found that CO2, CO, CH4, and H2 were the primary pyrolysis gases, while the pyrolysis oil consisted of extremely flammable substances formed by the dissociation and recombination of chemical bonds in the electrolyte solvent. After pyrolysis at 300 °C, fluorine and phosphate were present in the form of sodium fluoride and sodium phosphate. The stability of the residue was enhanced, and the environmental risk was reduced. By adding alkali (KOH/Ca(OH)2, 20 %), hexafluorophosphate in the electrolyte was transformed into fluoride and phosphate in the residue, thereby reducing the device's corrosion from fluorine-containing gas. This study provides a viable approach for managing the residual electrolyte in the waste lithium battery recovery process.

Plasmon-enhanced second harmonic generation of metal nanostructures.

As the most common nonlinear optical process, second harmonic generation (SHG) has important application value in the field of nanophotonics. With the rapid development of metal nanomaterial processing and chemical preparation technology, various structures based on metal nanoparticles have been used to achieve the enhancement and modulation of SHG. In the field of nonlinear optics, plasmonic metal nanostructures have become potential candidates for nonlinear optoelectronic devices because of their highly adjustable physical characteristics. In this article, first, the basic optical principles of SHG and the source of surface symmetry breaking in metal nanoparticles are briefly introduced. Next, the related reports on SHG in metal nanostructures are reviewed from three aspects: the enhancement of SHG efficiency by double resonance structures, the SHG effect based on magnetic resonance and the harmonic energy transfer. Then, the applications of SHG in the sensing, imaging and in situ monitoring of metal nanostructures are summarized. Future opportunities for SHG in composite systems composed of metal nanostructures and two-dimensional materials are also proposed.

[Cell membrane chromatography and its application progress in studies of traditional Chinese medicines].

As a novel bioaffinity chromatography technique, cell membrane chromatography (CMC) was first established by Professor He in 1996, with which combined high performance liquid chromatography, cytobiology, and receptor pharmacology. The cell membrane stationary phase (CMSP) consists of porous silica coated with active cell membranes. By immersing silica into a suspension of cell membranes, the whole surface of silica was covered by the cell membranes. In CMC, the interaction of drugs or compounds with the immobilized cell membrane or its receptors is investigated using liquid chromatography. In general, with the aim to provide scientific foundation for further development and application, this paper mainly focuses on the characteristics of the cell membrane stationary phase (CMSP), the CMC analytical system, and its applications in traditional Chinese medicines (TCMs) about CMC. With the development of CMC, the breakthrough progress of it in studying active components of TCMs field is expectant.

Hydrogen­rich saline promotes neuronal recovery in mice with cerebral ischemia through the AMPK/mTOR signal­mediated autophagy pathway.

This study explored the protective effect and mechanism of hydrogen­rich saline (HRS) on the neurological function of mice with cerebral ischemia. Effects of HRS on neurological function in mice with cerebral ischemia were evaluated by neurological function scores. Infarct volume and histological damage were evaluated by 2,3,5­triphenyl tetrazolium chloride staining (TTC staining). Golgi­Cox staining was conducted to measure the morphological changes of neuronal dendrites and dendritic spines. The expression of neuronal markers was detected by immunofluorescence. Western blot was used to detect protein expression. The infarct volume of mice in the HRS­H group decreased significantly compared to that of the distal middle cerebral artery occlusion (dMCAO) group. Mice in the HRS­H group had a lower neurological deficit score than that in the dMCAO group. Compared to the dMCAO group, the activity of superoxide dismutase (SOD) and the level of glutathione (GSH) significantly increased in the HRS­H group. Compared with the dMCAO group, the number of apoptotic cells in the HRS­H group decreased. Administration of HRS was shown to be able to decrease cavitation of the brain cortex after ischemia. The spine density in the HRS­H group increased compared to that of the dMCAO group. In the in vitro experiment, compared with the oxygen­glucose deprivation (OGD) group, the active oxygen content in the 75% HRM group decreased, and the mitochondrial membrane potential and adenosine triphosphate (ATP) content increased. Compared with the OGD group, the ratio of P­AMPK and the levels of LC3II/LC3I in the hydrogen­rich medium (HRM) group was upregulated, and P­mTOR levels and P62 levels in the HRM group were down­regulated. HRS can enhance neuroplasticity after ischemia and promote neurological recovery in mice with cerebral ischemia, which may involve the autophagy pathway mediated by the AMPK/mTOR signaling pathway.

Macrophage CARD9 mediates cardiac injury following myocardial infarction through regulation of lipocalin 2 expression.

Immune cell infiltration in response to myocyte death regulates extracellular matrix remodeling and scar formation after myocardial infarction (MI). Caspase-recruitment domain family member 9 (CARD9) acts as an adapter that mediates the transduction of pro-inflammatory signaling cascades in innate immunity; however, its role in cardiac injury and repair post-MI remains unclear. We found that Card9 was one of the most upregulated Card genes in the ischemic myocardium of mice. CARD9 expression increased considerably 1 day post-MI and declined by day 7 post-MI. Moreover, CARD9 was mainly expressed in F4/80-positive macrophages. Card9 knockout (KO) led to left ventricular function improvement and infarct scar size reduction in mice 28 days post-MI. Additionally, Card9 KO suppressed cardiomyocyte apoptosis in the border region and attenuated matrix metalloproteinase (MMP) expression. RNA sequencing revealed that Card9 KO significantly suppressed lipocalin 2 (Lcn2) expression post-MI. Both LCN2 and the receptor solute carrier family 22 member 17 (SL22A17) were detected in macrophages. Subsequently, we demonstrated that Card9 overexpression increased LCN2 expression, while Card9 KO inhibited necrotic cell-induced LCN2 upregulation in macrophages, likely through NF-κB. Lcn2 KO showed beneficial effects post-MI, and recombinant LCN2 diminished the protective effects of Card9 KO in vivo. Lcn2 KO reduced MMP9 post-MI, and Lcn2 overexpression increased Mmp9 expression in macrophages. Slc22a17 knockdown in macrophages reduced MMP9 release with recombinant LCN2 treatment. In conclusion, our results demonstrate that macrophage CARD9 mediates the deterioration of cardiac function and adverse remodeling post-MI via LCN2.