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This study aimed to investigate the role of salidroside (SAL) in the cellular communication between Müller cells and retinal ganglion cells in diabetic mice. The diabetes mellitus (DM) animal models were established by the intraperitoneal injection of streptozotocin and treatment with SAL via gavage or by the injection of IL-22BP into the vitreous cavity. Immunohistochemistry was used to measure the expression of the glial fibrillary acidic protein in Müller cells. The expression of IL-22 and IL-22Rα1 in retinal tissues was assessed by immunofluorescence. Western blotting was used to measure the expression of inflammatory and apoptosis-related proteins. Hematoxylin–eosin staining, TUNEL staining, and flow cytometry were used to analyze the apoptosis of retinal ganglion cells. The effect of cellular interactions was explored by Transwell assays. Western blotting showed that glial fibrillary acidic protein, IL-22 protein expression was significantly upregulated in the DM animal models compared with the control mice. Immunofluorescence showed that IL-22 was highly expressed in Müller cells and IL-22Rα1 was expressed in ganglion cells in the retina of DM mice. Hematoxylin–eosin and TUNEL staining results showed an increase in the number of ganglion cells apoptotic in DM. However, SAL reversed these phenomena. Meanwhile, after coculture with Müller cells, Western blotting suggested that ganglion cells secreted p-STAT3, and c-caspase3 protein expression was increased. More interestingly, the treatment of IL-22BP and SAL inhibited the expression of the p-STAT3 and c-caspase3 proteins. Flow cytometry indicates that compared with the control group, the apoptosis rate of ganglion cells was increased in the high glucose group, while the apoptosis rate of cells in the recombinant IL-22 protein group was significantly increased, while the SAL inhibited ganglion cells apoptosis. SAL inhibits the apoptosis of retinal ganglion cells via the IL-22/STAT3 pathway in Müller cells. [ABSTRACT FROM AUTHOR]

Background: CD4 + T helper (Th)22 cells play a regulatory role in autoimmune diseases such as type 1 diabetes mellitus. The Th22-related cytokine interleukin (IL)-22, the expression of which is increased in diabetes mellitus (DM), can act as a neurotrophic factor to protect neurons from apoptosis. Paradoxically, neuronal apoptosis and learning and memory decline occur in DM. In this study, we investigated the relationship between IL-22 and its receptors IL-22Rα1 and IL-22 binding protein (IL-22BP, a soluble inhibitor of IL-22) in diabetic encephalopathy (DE) and the effects of IL-22 on hippocampal neurons, learning and memory. Methods: A C57BL/6 mouse model of diabetes was constructed by intraperitoneal injection of streptozotocin. The mice were randomly divided into 4 groups: the control group, diabetes group, diabetes + recombinantIL-22 (rIL-22) group and diabetes + IL-22BP group. The Morris water maze test was used to evaluate learning and memory, the expression of IL-22 was measured by ELISA, and Evans Blue staining was used to evaluate blood–brain barrier permeability. Quantitative reverse transcription polymerase chain reaction (RT-qPCR) was used to measure the mRNA expression of IL-22 and IL-22Rα1 in the hippocampus. The morphology and number of hippocampal neurons were assessed by Nissl staining, and TUNEL staining was used to detect hippocampal neuronal apoptosis. Immunofluorescence was used to analyze IL-22Rα1 expression and localization in hippocampus, and Western blotting was used to evaluate the expression of IL-22, IL-22Rα1, IL-22BP, and the apoptosis related proteins Caspase-3 and C-caspase-3. Results: Compared with those in the control group, mice in the diabetes group showed cognitive decline; apoptosis of hippocampal neurons; increased expression of hippocampal Caspase-3, C-Caspase-3, IL-22, IL-22Rα1, and IL-22BP; and a decreased IL-22/IL-22BP ratio. Learning and memory were improved, neuronal apoptosis was attenuated, IL-22Rα1 expression and the IL-22/IL-22BP ratio were increased, and caspase-3 and C-caspase-3 expression was decreased in the rIL-22-treated group compared with the diabetes group. IL-22BP treatment aggravated diabetic cognitive dysfunction and pathological alterations in the hippocampus, decreased the IL-22/IL-22BP ratio, and increased the expression of caspase-3 and C-caspase-3 in mice with diabetes. Conclusion: A decrease in the IL-22/IL-22BP ratio plays an important role in diabetic cognitive dysfunction, and rIL-22 can effectively alleviate DE. Herein, we shed light on the interaction between IL-22 and IL-22BP as therapeutic targets for DM. [ABSTRACT FROM AUTHOR]

Long-term hypoxia can induce oxidative stress and apoptosis in hippocampal neurons that can lead to brain injury diseases. Astragaloside IV (AS-IV) is widely used in the antiapoptotic therapy of brain injury diseases. However, its mechanism of action is still not fully understood. In this study, we investigated the effect of AS-IV on hypoxia-induced oxidative stress and apoptosis in hippocampal neurons and explored its possible mechanism. In vivo, mice were placed in a hypoxic circulatory device containing 10% O2 and gavaged with AS-IV (60 and 120 mg/kg/d) for 4 weeks. In vitro, mouse hippocampal neuronal cells (HT22) were treated with hypoxia (1% O2) for 24 hours in the presence or absence of AS-IV, MDL-28170 (calpain-1 inhibitor), or YC-1 (HIF-1α inhibitor). The protective effect of AS-IV on brain injury was further explored by examining calpain-1 knockout mice. The results showed that hypoxia induced damage to hippocampal neurons, impaired spatial learning and memory abilities, and increased oxidative stress and apoptosis. Treatment with AS-IV or calpain-1 knockout improved the damage to hippocampal neurons and spatial learning and memory, attenuated oxidative stress and inhibited cell apoptosis. These changes were verified in HT22 cells. Overexpression of calpain-1 abolished the improvement of AS-IV on apoptosis and oxidative stress. In addition, the effects of AS-IV were accompanied by decreased calpain-1 and HIF-1α expression, and YC-1 showed a similar effect as AS-IV on calpain-1 and caspase-3 expression. In conclusion, this study demonstrates that AS-IV can downregulate the calpain-1/HIF-1α/caspase-3 pathway and inhibit oxidative stress and apoptosis of hippocampal neurons induced by hypoxia, which provides new ideas for studying the antiapoptotic activity of AS-IV. [ABSTRACT FROM AUTHOR]

T helper 22 (Th22) cells have been implicated in diabetic retinopathy (DR), but it remains unclear whether Th22 cells involve in the pathogenesis of DR. To investigate the role of Th22 cells in DR mice, the animal models were established by intraperitoneal injection of STZ and confirmed by fundus fluorescein angiography and retinal haematoxylin–eosin staining. IL-22BP was administered by intravitreal injection. IL-22 level was measured by ELISA in vivo and in vitro. The expression of IL-22Rα1 in the retina was assessed by immunofluorescence. We assessed GFAP, VEGF, ICAM-1, inflammatory-associated factors and the integrity of blood–retinal barrier in control, DR, IL-22BP, and sham group. Müller cells were co-cultured with Th22 cells, and the expression of the above proteins was measured by immunoblotting. Plasmid transfection technique was used to silence Act1 gene in Müller cells. Results in vivo and in vitro indicated that Th22 cells infiltrated into the DR retinal and IL-22Rα1 expressed in Müller cells. Th22 cells promoted Müller cells activation and inflammatory factor secretion by secreting IL-22 compared with high-glucose stimulation alone. In addition, IL-22BP ameliorated the pathological alterations of the retina in DR. Inhibition of the inflammatory signalling cascade through Act1 knockdown alleviated DR-like pathology. All in all, the results suggested that Th22 cells infiltrated into the retina and secreted IL-22 in DR, and then IL-22 binding with IL-22Rα1 activated the Act1/TRAF6 signal pathway, and promoted the inflammatory of Müller cells and involved the pathogenesis of DR. [ABSTRACT FROM AUTHOR]

The development of low-cost and high-activity Fe-based anodic materials is very promising for the present solid-state energy storage. In this work, we successfully synthesize ultra-long KFeS2 nanowires on an Fe foam substrate via a simple hydrothermal strategy. Physical characterization shows that the as-synthesized KFeS2 nanowires possess merits of good morphological uniformity, considerable mass loading (∼76 mg cm−2) and strong affinity for the substrate. As an anode for solid-state energy storage, the areal capacity of the KFeS2 electrode can reach 21.1 mA h cm−2 (at 50 mA cm−2), which is greatly enhanced as compared to the previous best result (<2 mA h cm−2), and the durability test indicates that the electrode only shows a small working potential shift after long-time cycling. The assembled KFeS2//NiO single solid-state battery exhibits an enhanced energy density of 175.2–135.8 W h m−2 at a power range of 436.5–1750 W m−2. By using in situ Raman and in situ electrochemical impedance spectroscopy (EIS) technologies, the dynamics of the electrode and the energy storage mechanism of the KFeS2 nanowires are revealed. This work achieves a milestone in the development of high-performance Fe-based film anodes for solid-state energy storage, especially aiming for low-cost and large-scale application. [ABSTRACT FROM AUTHOR]

Nickel compounds, especially Ni(HCO3)2 (here denoted as NiC), have been widely combined with other materials to obtain composites with a more favorable structure that exhibit excellent electrochemical performance as supercapacitors. Unfortunately, the complicated processes for preparing such composites directly restrict their further application. Herein, we prepared a NiC/nickel tetraphosphate (Ni(P4O11)) nanocomposite (NiC/NiP) by introducing ions into the NiC reaction system; this composite can be applied in high-performance supercapacitors. The micromorphology of NiC/NiP material displayed an appropriate combination of NiP nanowires and thin NiC nanosheets, which provide sufficient active sites, short ion diffusion paths and fast ion diffusion speeds. NiC/NiP material exhibited an excellent rate performance of 70.2% retained capacity, although the current was increased by 15 times (1196 F g−1 at 2.0 A g−1 and 840 F g−1 at 30 A g−1). The energy density of a NiC/NiP//active carbon (AC) asymmetric supercapacitor fabricated in 6 M KOH was as much as 39.02 W h kg−1 and 26.67 W h kg−1 under corresponding power densities of 160 W kg−1 and 8000 W kg−1, respectively. The asymmetric supercapacitor delivered a stable cyclic performance of 78% capacitive retention after 5000 continuous charge/discharge cycles. More importantly, a 2.5 V light-emitting diode was lit successfully by two NiC/NiP//AC asymmetric supercapacitors in series. These results confirm that NiC/NiP nanocomposite has great potential in practical applications of electrochemical energy storage devices. [ABSTRACT FROM AUTHOR]

In this work, a new type of Ti-Se conversion coating was formed on the surface of an aluminum alloy using titanium and selenide as the main salts. An examination of the surface morphology, composition and microstructure of the conversion coating was done using scanning electron microscopy, energy-dispersive spectrometry and x-ray photoelectron spectroscopy. The results showed that the surface of the conversion coating possessed a reticular structure with uniform cracks and a dense coating with a thickness of 0.4 μm. The elements in the conversion coating were C, O, Ti, Al and Se. The corrosion resistances of both the Ti-Se conversion coatings and the bare substrate were evaluated by an immersion test, polarization curves and electrochemical impedance spectroscopy. The results showed that the corrosion current of the conversion coating improved the corrosion resistance of the aluminum alloy and effectively protected the aluminum alloy in the immersion test. Furthermore, the corrosion current obtained from the polarization curves and electrochemical impedance spectroscopy decreased by one order of magnitude after the formation of the Ti-Se conversion coating, suggesting an improvement in polarization resistance. [ABSTRACT FROM AUTHOR]

To construct a suitable structure for both electronic conduction and ionic transport towards supercapacitors, peanut-like hierarchical manganese carbonate (MnCO3) microcrystals assembled with floss-like nanowires are synthesized via a hydrothermal process and primarily used as an active material for supercapacitors. The formation mechanism is illustrated by means of a dissolution–recrystallization process and magnetically driven self-assembly. The electrode with peanut-like hierarchical MnCO3 microcrystals exhibits a high specific capacitance of 293.7 F g−1 and a superior cycle stability of 71.5% retention after 6000 cycles, which are higher than those of the reported Mn-based active materials in alkaline electrolytes. The asymmetric supercapacitor, assembled with the peanut-like MnCO3 electrode as the positive electrode and a home-made porous carbon electrode as the negative electrode, exhibits an energy density of 14.7 W h kg−1 at a power density of 90.2 W kg−1 and an energy density of up to 11.0 W h kg−1 at 3.3 kW kg−1. An as-assembled all-solid-state supercapacitor series can light up a LED indicator for 10 min, indicating a promising practical application of peanut-like MnCO3 microcrystals. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) anchored porous manganese sulfide nanocrystals (MnS/GO-NH3) were obtained via a facile hydrothermal method based on the Kirkendall effect. The honeycomb-like manganese sulfide nanocrystals (40–80 nm) and the three-dimensional sandwich structure endow the MnS/GO-NH3 with high supercapacitive performance when it was used as a supercapacitor material. The MnS/GO-NH3 electrode exhibits high specific capacitance (390.8 F g−1 at 0.25 A g−1), high rate capacity (78.7% retention at 10 A g−1) and stable cycle life (81.0% retention after 2000 cycles), which are superior to those of GO anchored MnS floccules (MnS/GO) and manganese hydroxide (Mn(OH)2/GO). As a novel material for supercapacitors, the charge–discharge mechanism of the MnS/GO-NH3 composite is proposed via detailed investigation. Asymmetric supercapacitors, assembled with MnS/GO-NH3 as the positive material and activated carbon as the negative electrode, reveal a high specific capacitance (73.63 F g−1), a high energy density of 14.9 W h kg−1 at 66.5 W kg−1 and even 12.8 W h kg−1 at a high power density of 4683.5 W kg−1. [ABSTRACT FROM AUTHOR]

Floss-like Ni-Co binary hydroxides (FL-NCOH), assembled by whisker-like nanowires, are synthesized via a facile hydrothermal process with sodium dodecyl benzene sulfonate (SDBS) as the soft template. The forming process of FL-NCOH is clarified by tuning the hydrothermal reaction time. The result indicates that floccule-like nickel-cobalt hydroxide nanoclusters gradually become longer and slenderer nanowires to form FL-NCOH with the increase of reaction time. The dissolution-recrystallization of hydroxide plays an important role in the morphology control of nickel-cobalt hydroxide. The high specific surface area (106.5 m g) and the suitable 3D structure endow the as-prepared FL-NCOH material high specific capacitance (up to 918.9 F g at the current density of 0.2 A g), good high-rate performance (594.2 F g even at 10.0 A g), and long cycle life (98.7 % capacitance retention after 3000 charge-discharge cycles at 2.0 A g). [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Monodispersed hollow spindle-like nanosphere (HS-NS) and tetrapod nanorod (TP-NR) MnS nanocrystals are obtained via a facile template-free hydrothermal process. The MnS nanocrystals are used as supercapacitor materials and they exhibit high performances. The TP-NR nanocrystals show a higher specific capacitance of 704.5 F g−1 compared to the HS-NS nanocrystals, and both show higher values compared to manganese oxide. [ABSTRACT FROM AUTHOR]

Carbon supported Pt-Pd (Pt-Pd/C) catalysts with different Pt/Pd ratios were prepared by microwave assisted ethylene glycol method and characterized by X-ray diffraction (XRD), transmission electron spectroscopy (TEM) and electrochemical measurements. The results reveal that the metal nanoparticles of Pt-Pd/C catalysts are uniformly dispersed on the carbon support and exist as alloys with face centered cubic (FCC) structures. The effects of both preparation process and Pt/Pd ratios on the structure and catalytic activity of the Pt-Pd/C catalysts were investigated. With the increase of Pd content, the catalytic activity for ORR is deteriorated due to the increased metal particle size of Pt-Pd/C catalysts, while improving the methanol tolerance. Among the Pt-Pd/C catalysts with different Pt/Pd ratios, the PtPd/C catalyst, which have the highest Pt/Pd ratios, exhibits higher specific mass activities toward oxygen reduction reaction (ORR) than that of the commercial Pt/C catalyst. [ABSTRACT FROM AUTHOR]

Three commercial carbon materials for supercapacitor were investigated by physicochemical characterization, electrochemical measurements and surface treatment to explore the effects of specific surface area, electrolyte and surface functional groups on the specific capacitance, charge storage mode and high rate performance of carbon materials. Results indicate that the specific surface area of carbon material plays dominate role in the specific capacitance. The electrolytes have remarkable effects on the specific capacitance and high rate performance. Investigation of HNO treated Vulcan XC-72 carbon material reveals that the treatment can increase the specific surface area and surface functional groups, which observably improve the specific capacitance of the XC-72 carbon material. The surface functional groups contribute to the pseudo-capacitance of the carbon material. [ABSTRACT FROM AUTHOR]

In this paper, Zn2TiO4and TiN nanofibers were prepared by a facile combination of electrospinning followed by thermolysis under different atmospheres. An N,N-dimethyl formamide (DMF)–ethanol solution of poly(vinylpyrrolidone) (PVP), Ti(iv)–isopropoxide (Ti(OC4H9)4) and zinc acetate (ZnAc) was used as the electrospinning precursor and the electrospun nanofibers were calcined at 600 °C in air to generate Zn2TiO4nanofibers. Subsequently, a conversion from Zn2TiO4nanofibers to TiN nanofibers was realized through a heat treatment at 1000 °C under an ammonia atmosphere. Investigations using field-emission scanning electron and transmission electron microscopes (FESEM and TEM) revealed the nano-scale fibrous morphology of the obtained products. Energy-dispersive spectroscopy (EDS) and X-ray diffraction (XRD) studies confirmed the chemical composition and crystalline structure of the Zn2TiO4and TiN nanofibers, respectively. The electrochemical properties of the as-prepared TiN nanofibers indicated that the capacitance characteristic of the TiN phase was the electric double-layer capacitance. The value of the specific capacitance gradually decreased with the increase of discharge current density. [ABSTRACT FROM AUTHOR]