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@#Objective To explore the protective effects and mechanism of Zuogui Jiangtang Jieyu Formula (左归降糖解郁方, ZGJTJYF) on hippocampal neurons in rats of diabetes complicated with depression (DD) via the TRP/KYN metabolic pathway. Methods (i) In vivo experiments: 60 specified pathogen free (SPF) grade male Sprague-Dawley (SD) rats were randomly divided into six groups with 10 rats in each groups: control, DD model, positive (1.8 mg/kg fluoxetine + 0.18 g/kg metformin), high-dose ZGJTJYF (ZGJTJYF-H, 40.500 g/kg ZGJTJYF), middle-dose ZGJTJYF (ZGJTJYF-M, 20.250 g/kg ZGJTJYF), and low-dose ZGJTJYF (ZGJTJYF-L, 10.125 g/kg ZGJTJYF) groups. Except for the control group, other groups were established DD model by high-fat emulsion intake with single tail vein streptozotocin (STZ) and four weeks of chronic unpredictable mild stress (CUMS). All drug administration groups were treated by gavage during CUMS modeling, and the control and model groups were given equal amount of distilled water. After four weeks, the serum levels of blood glucose and glycosylated hemoglobin were measured to determine the hypoglycemic effect of ZGJTJYF. Moreover, the open field test and Morris water maze test were performed to evaluate the antidepressant effect of ZGJTJYF. Changes in 5-hydroxytryptamine (5-HT) level were detected via high-performance liquid chromatography with electrochemical detection (HPLC-ECD); the levels of tryptophan (TRP), kynurenine (KYN), and indoleamine 2,3-dioxygenase (IDO) in the hippocampus were detected using enzyme-linked immunosorbent assay (ELISA); the protein expression levels of synaptophysin (SYN) and postsynaptic density material-95 (PSD-95) were detected via immunohistochemistry (IHC); and the protein expression levels of N-methyl-D-aspartate receptor (NR) 2A and NR2B were detected using Western blot. (ii) In vitro experiments: five SPF grade SD pregnant rats (E16 – 18) were used to obtain primary hippocampal neurons (Ne), six SD new-born rats were used to collected primary astrocytes (As) and microglia (MG), and to establish a Ne-As-MG co-culture system. All co-culture systems were divided into six groups: control (PBS), model [150 mmol/L glucose + 200 μmol/L corticosterone (G&P) + PBS], blank (G&P + blank serum), positive (G&P + positive drug-containing serum), ZGJTJYF (G&P + ZGJTJYF serum), and 1-methyl-D-tryptophan (1-MT, IDO inhibitor) (G&P + 1-MT) groups. After 18 h of intervention by corresponding treatment, immunofluorescence was used to analyze the protein expression levels of SYN, PSD-95, NR2A, and NR2B; ELISA was performed to measure the levels of interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α , and TRP/KYN metabolic pathway-related factors [TRP, KYN, kynurenine acid (KYNA), quinolinic acid (QUIN)]. Results (i) In vivo experimental<italic/> results showed that ZGJTJYF-M and ZGJTJYF-L significantly improved the elevated blood glucose state of DD rats (P < 0.01 and P < 0.05, respectively); ZGJTJYF-H, ZGJTJYF-M, and ZGJTJYF-L increased their autonomous activity, learning, and memory ability (P < 0.01, P < 0.01, and P < 0.05, respectively). Moreover, the levels of 5-HT and TRP were significantly increased (P < 0.01), and the levels of KYN and IDO were significantly decreased in the hippocampus (P < 0.01) of rats after ZGJTJYF-M treatment. The protein expression levels of SYN and PSD-95 were significantly upregulated in hippocampal neurons (P < 0.01), while the abnormal activation of NR2A and NR2B was markedly inhibited in hippocampus (P < 0.05) of rats after ZGJTJYF-M treatment. (ii) In vitro experimental results showed that ZGJTJYF-containing serum significantly increased the protein expression levels of SYN and PSD-95 in hippocampal neurons (P < 0.01), decreased the levels of IL-1β (P < 0.01), IL-6 (P < 0.05), TNF-α (P < 0.01), IDO (P < 0.05), KYN (P < 0.05), and QUIN (P < 0.01), and increased the levels of TRP and KYNA (P < 0.01) in the simulated DD state. ZGJTJYF also had an significantly inhibitory effect on the abnormal activation of NR2A and NR2B in neurons (P < 0.05) in a stimulated DD state. Conclusion ZGJTJYF can effectively improve 5-HT deficiency in the hippocampus of rats by inhibiting IDO expression and regulating the TRP/KYN metabolic pathway, and it has a favorable protective effect on hippocampal neuron injury caused by DD. Therefore, ZGJTJYF is an effective potential therapeutic drug for the prevention and treatment of DD.
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Objective@#To investigate the first family cluster of COVID-19 in Lanzhou, so as to provide basis for improving the COVID-19 outbreak prevention capacity. @*Methods @# On January 23, the First Hospital of Lanzhou University reported two suspected cases of COVID-19.According to the COVID-19 Epidemiological Investigation Plan ( second edition ) , general information, disease diagnosis and treatment, clinical symptoms, laboratory test results, household environment, exposure history and close contacts were collected to figure out the source of infection and routes of transmission. @*Results@#This family cluster lasted 29 days, from January 23 to February 21, reporting nine confirmed cases ( one death ) and one asymptomatic case. There were three imported cases from Wuhan, who were the source of the cluster; and seven secondary cases, who all had close contact with the imported cases during daily life or through having dinners. The secondary attack rate was 41.18% ( 7/17 ) . Among 9 confirmed cases, the incubation period ranged from four to ten days, with a median of nine days. Except for seven secondary cases, 24 close contacts were found and detected negative in the nucleic acid tests.@*Conclusions@#The first family cluster of COVID-19 in Lanzhou is caused by the imported cases from Wuhan. All the secondary cases have had dinners and/or had contact with the imported cases, thus they are infected through respiratory droplets and close contact.
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OBJECTIVE Transient outward potassium current (Ito) plays a crucial role in cardiac phase 1 repolarization and the channels are assembled by pore-forming α-subunits (Kv4.2 or Kv4.3) and auxiliary subunits (KChIP2 and DPP6). Previous studies have found that the compound NS5806 increases Ito in canine ventricular cardiomyocytes through slowing current decay. Here, we reported that NS5806 produced an acute inhibitory action on Ito in mouse ventricular cardiomyocytes and human induced pluripotent stem cell-derived cardiomyocytes (hiPS-CM). METHODS Whole-cell patch-clamp was used to record Ito in native myocytes and in HEK cells expressing cloned Kv4.x/KChIP2/DPP6 channels; Western-blot detected the channel protein expression. RESULTS In isolated mouse ventricular cardiomyocytes, NS5806 (0.1-30 μmol·L-1) inhibited Ito in a concentration-dependent manner with IC50 of 6.6±1.9 μmol·L-1. The current decay was significantly accelerated with a time constant from 53.8±5.5 to 41.8±3.0 ms at +60 mV (P<0.01). Similarly, NS5806 concentration-dependently reduced the Ito peak current amplitude with an acceleration of current decay. In addition, NS5806 increased IKv4.2/KChIP2 and delayed current decay, but decreased IKv4.2/KChIP2/DPP6 with the acceleration of current decay. The inhibitory action on the current was more potent if DPP6 expression level was increased from Kv4.2/KChIP2/DPP61:1:1 to 1:1:3. Western-blot showed a higher expression of DPP6 protein in mouse heart and in hiPS- CM compared to canine heart. Moreover, specific knock- down DPP6 expression by siRNA antagonized the inhibitory action of NS5806 in hiPS-CM. Our results pointed to an important role of DPP6 subunit in the regulation of NS5806 on the channel. By using molecular docking simulation, five interaction sites with high possibility between KChIP2 and DPP6 were identified. Mutations of those sites changed the inhibitory action of NS58056 into excitatory effect on the current with the delay of current decay. CONCLUSION NS5806 significantly inhibits Ito by accelerating current decay in mouse cardiomyocytes and hiPS-CM. The effect depends on the interaction between DPP6 and KChIP2 subunits.