Integration of metabolomics and transcriptomics reveals that Da Chuanxiong Formula improves vascular cognitive impairment via ACSL4/GPX4 mediated ferroptosis.

ETHNOPHARMACOLOGICAL RELEVANCE: Da Chuanxiong Formula (DCX) is a traditional herbal compound composed of Gastrodia elata Bl. and Ligusticum chuanxiong Hort, which could significantly enhance blood circulation and neuroprotection, showing promise in treating Vascular Cognitive Impairment (VCI). AIM OF STUDY: This study aims to elucidate the potential of DCX in treating VCI and its underlying mechanism. MATERIALS AND METHODS: Firstly, the cognitive behavior level, blood flow changes, and brain pathology changes were evaluated through techniques such as the Morris water maze, step-down, laser speckle, coagulation analysis, and pathological staining to appraise the DCX efficacy. Then, the DCX targeting pathways were decoded by merging metabolomics with transcriptomics. Finally, the levels of reactive oxygen species (ROS), Fe2+, and lipid peroxidation related to the targeting signaling pathways of DCX were detected by kit, and the expression levels of mRNAs or proteins related to ferroptosis were determined by qPCR or Western blot assays respectively. RESULTS: DCX improved cognitive abilities and cerebral perfusion significantly, and mitigated pathological damage in the hippocampal region of VCI model rats. Metabolomics revealed that DCX was able to call back 33 metabolites in plasma and 32 metabolites in brain samples, and the majority of the differential metabolites are phospholipid metabolites. Transcriptomic analysis revealed that DCX regulated a total of 3081 genes, with the ferroptosis pathway exhibiting the greatest impact. DCX inhibited ferroptosis of VCI rates by decreasing the levels of ferrous iron, ROS, and malondialdehyde (MDA) while increasing the level of superoxide dismutase (SOD) and glutathione (GSH) in VCI rats. Moreover, the mRNA and protein levels of ACSL4, LPCAT3, ALOX15, and GPX4, which are related to lipid metabolism in ferroptosis, were also regulated by DCX. CONCLUSION: Our research findings indicated that DCX could inhibit ferroptosis through the ACSL4/GPX4 signaling pathway, thereby exerting its therapeutic benefits on VCI.

Chaihu Guizhi Ganjiang Decoction attenuates nonalcoholic steatohepatitis by enhancing intestinal barrier integrity and ameliorating PPARα mediated lipotoxicity.

BACKGROUND: Nonalcoholic steatohepatitis (NASH) is a prominent cause of liver-related death that poses a threat to global health and is characterized by severe hepatic steatosis, lobular inflammation, and ballooning degeneration. To date, no Food and Drug Administration-approved medicine is commercially available. The Chaihu Guizhi Ganjiang Decoction (CGGD) shows potential curative effects on regulation of blood lipids and blood glucose, mitigation of organism inflammation, and amelioration of hepatic function. However, the overall regulatory mechanisms underlying its effects on NASH remain unclear. PURPOSE: This study aimed to investigate the efficiency of CGGD on methionine- and choline-deficient (MCD)-induced NASH and unravel its underlying mechanisms. METHODS: A NASH model of SD rats was established using an MCD diet for 8 weeks, and the efficacy of CGGD was evaluated based on hepatic lipid accumulation, inflammatory response, and fibrosis. The effects of CGGD on the intestinal barrier, metabolic profile, and differentially expressed genes (DEGs) profile were analyzed by integrating gut microbiota, metabolomics, and transcriptome sequencing to elucidate its mechanisms of action. RESULTS: In MCD-induced NASH rats, pathological staining demonstrated that CGGD alleviated lipid accumulation, inflammatory cell infiltration, and fibrosis in the hepatic tissue. After CGGD administration, liver index, liver weight, serum alanine aminotransferase (ALT), and aspartate aminotransferase (AST) contents, liver triglycerides (TG), and free fatty acids (FFAs) were decreased, meanwhile, it down-regulated the level of proinflammatory mediators (TNF-α, IL-6, IL-1ß, MCP-1), and up-regulated the level of anti-inflammatory factors (IL-4, IL-10), and the expression of liver fibrosis markers TGFß, Acta2, Col1a1 and Col1a2 were weakened. Mechanistically, CGGD treatment altered the diversity of intestinal flora, as evidenced by the depletion of Allobaculum, Blautia, norank_f_Erysipelotrichaceae, and enrichment of the probiotic genera Roseburia, Lactobacillus, Lachnoclostridium, etc. The colonic histopathological results indicated that the gut barrier damage recovered in the CGGD treatment group, and the expression levels of colonic short-chain fatty acids (SCFAs)-specific receptors FFAR2, FFAR3, and tight junction (TJs) proteins ZO-1, Occludin, Claudin-1 were increased compared with those in the model group. Further metabolomic and transcriptomic analyses suggested that CGGD mitigated the lipotoxicity caused by glycerophospholipid and eicosanoid metabolism disorders by decreasing the levels of PLA2G4A, LPCAT1, COX2, and LOX5. In addition, CGGD could activate the inhibitory lipotoxic transcription factor PPARα, regulate the proteins of FABP1, APOC2, APOA2, and LPL to promote fatty acid catabolism, and suppress the TLR4/MyD88/NFκB pathway to attenuate NASH. CONCLUSION: Our study demonstrated that CGGD improved steatosis, inflammation, and fibrosis on NASH through enhancing intestinal barrier integrity and alleviating PPARα mediated lipotoxicity, which makes it an attractive candidate for potential new strategies for NASH prevention and treatment.

TLDA: A transfer learning based dual-augmentation strategy for traditional Chinese Medicine syndrome differentiation in rare disease.

The Traditional Chinese Medicine (TCM) has demonstrated its significant medical value over the decades, particularly during the COVID-19 pandemic. TCM-AI interdisciplinary models have been proposed to model TCM knowledge, diagnosis, and treatment experiments in clinical practice. Among them, numerous models have been developed to simulate the syndrome differentiation process of human TCM doctors for automatic syndrome diagnosis. However, these models are designed for normal scenarios and trained using a supervised learning paradigm which needs tens of thousands of training samples. They fail to effectively differentiate syndromes in rare disease scenarios where the available TCM electronic medical records (EMRs) are very limited for each unique syndrome. To address the challenge of rare diseases, this study proposes a simple yet effective method called Transfer Learning based Dual-Augmentation (TLDA). TLDA aims to augment the limited EMRs at both the sample-level and feature-level, enriching the pathological and medical information during training. Extended experiments involving 11 comparison models, including the state-of-the-art model, demonstrate the effectiveness of TLDA. TLDA outperforms all comparison models by a significant margin. Furthermore, TLDA can also be extended to other medical tasks when the EMRs for diagnosis are limited in samples.

m6A RNA Methylation Regulators Contribute to Predict and as a Therapy Target of Pulmonary Fibrosis.

Background: Pulmonary fibrosis is difficult to treat. Early diagnosis and finding potential drug therapy targets of pulmonary fibrosis are particularly important. There were still various problems with existing pulmonary fibrosis markers, so it is particularly important to find new biomarkers and drug treatment targets. m6A (N6,2'-O-dimethyladenosine) RNA methylation was the cause of many diseases, and it is regulated by m6A methylation regulators. So, whether RNA methylation regulators can be a diagnostic marker and potential drug therapy target of early pulmonary fibrosis needs to be explored. Materials and Methods: Using GSE110147 and GSE33566 in the GEO database to predict the m6A methylation regulators that may be related to the development of pulmonary fibrosis, we used 10 mg/ml bleomycin to induce mouse pulmonary fibrosis models and human pulmonary fibrosis samples, to confirm whether this indicator can be an early diagnostic marker of pulmonary fibrosis. Results: According to the database prediction results, METTL3 can predict the occurrence and development of pulmonary fibrosis, and the results of MASSON and HE staining show that the fibrosis model of mice is successful, and the fibrosis of human samples is obvious. The results of immunohistochemistry showed that the expression of METTL3 was significantly reduced in pulmonary fibrosis. Conclusions: The m6A methylation regulator METTL3 can be considered as an important biomarker for diagnosing pulmonary fibrosis occurrence, furthermore it could be considered as a drug target because of its low expression in pulmonary fibrosis.

Oral Administration of Omega-3 Fatty Acids Attenuates Lung Injury Caused by PM2.5 Respiratory Inhalation Simply and Feasibly In Vivo.

For developing an effective interventional approach and treatment modality for PM2.5, the effects of omega-3 fatty acids on alleviating inflammation and attenuating lung injury induced by inhalation exposure of PM2.5 were assessed in murine models. We found that daily oral administration of the active components of omega-3 fatty acids, docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA) effectively alleviated lung parenchymal lesions, restored normal inflammatory cytokine levels and oxidative stress levels in treating mice exposed to PM2.5 (20 mg/kg) every 3 days for 5 times over a 14-day period. Especially, CT images and the pathological analysis suggested protective effects of DHA and EPA on lung injury. The key molecular mechanism is that DHA and EPA can inhibit the entry and deposition of PM2.5, and block the PM2.5-mediated cytotoxicity, oxidative stress, and inflammation.

Volatile 1-octanol of tea (Camellia sinensis L.) fuels cell division and indole-3-acetic acid production in phylloplane isolate Pseudomonas sp. NEEL19.

Tea leaves possess numerous volatile organic compounds (VOC) that contribute to tea's characteristic aroma. Some components of tea VOC were known to exhibit antimicrobial activity; however, their impact on bacteria remains elusive. Here, we showed that the VOC of fresh aqueous tea leaf extract, recovered through hydrodistillation, promoted cell division and tryptophan-dependent indole-3-acetic acid (IAA) production in Pseudomonas sp. NEEL19, a solvent-tolerant isolate of the tea phylloplane. 1-octanol was identified as one of the responsible volatiles stimulating cell division, metabolic change, swimming motility, putative pili/nanowire formation and IAA production, through gas chromatography-mass spectrometry, microscopy and partition petri dish culture analyses. The bacterial metabolic responses including IAA production increased under 1-octanol vapor in a dose-dependent manner, whereas direct-contact in liquid culture failed to elicit such response. Thus, volatile 1-octanol emitting from tea leaves is a potential modulator of cell division, colonization and phytohormone production in NEEL19, possibly influencing the tea aroma.

Effect of Exercise on Quality of Life in Parkinson's Disease: A Systematic Review and Meta-Analysis.

BACKGROUND: Exercise has an integral impact on the physical and mental wellbeing of patients with Parkinson's disease (PD), yet no comprehensive and quantitative analysis has been conducted on the effect of exercise on quality of life (QoL) in these patients. This study aimed to evaluate the effect of exercise on overall QoL and different domains of QoL in people with PD, as well as investigating the influence of factors such as the exercise type and intervention period. METHODS: Databases, such as PubMed, Embase, and Cochrane Central Register of Controlled Trials, were searched since inception to August 14, 2018 to identify randomized controlled trials that compare the effect of exercise versus no intervention on QoL in PD patients. Following the subgroup analysis, heterogeneity was further explored. The quality of eligible studies was assessed according to PRISMA guidelines. RESULTS: 20 studies were included with 1,143 participants in total. A meta-analysis showed a significant improvement in QoL after exercise intervention in PD patients (SMD = -0.24, 95% CI = -0.36 to -0.12, P < 0.001). A subgroup analysis of exercise types revealed significant QoL improvement with aerobic exercise, martial arts, and dance, but not anaerobic exercise and combined exercise. Interventions lasting 12 weeks or longer improved QoL significantly. CONCLUSIONS: Exercise interventions, especially aerobic exercise, dance, and Tai Chi, significantly improve QoL in PD patients. At least 12 weeks of exercise is needed to bring about significant benefits.

Amelioration of PM2.5-induced lung toxicity in rats by nutritional supplementation with biochanin A.

Epidemiological studies have shown that particulate matter with an aerodynamic diameter less than 2.5 µm (PM2.5) is closely associated with human health issues, especially pulmonary diseases such as chronic obstructive pulmonary disease (COPD), asthma and lung cancer. In this study, particles were characterized by scanning electron microscopy (SEM), microbeam energy-dispersive X-ray spectroscopy (EDS), inductively coupled plasma mass spectrometry (ICP-MS) and high-performance liquid chromatography (HPLC). A rat model of PM2.5 exposure was established by nonsurgical intratracheal instillation, and the effects of biochanin A (BCA) treatment were examined. BCA showed a protective effect; it reduced PM2.5-induced apoptosis and the production of proinflammatory factors, such as tumor necrosis factor-α (TNF-α), interleukin-2 (IL-2), interleukin-6 (IL-6), and the chemokine interleukin-8 (IL-8), as measured using ELISA. These effects were accompanied by increases in the levels of antioxidant enzymes and decreases in the levels of malondialdehyde (MDA), lactate dehydrogenase (LDH) and alkaline phosphatase (AKP). Furthermore, isobaric tag for relative and absolute quantitation (iTRAQ)-based analytical techniques and bioinformatics tools were used to identify putative biomarkers, including XRCC1, MP2K5, IGJ, and F1LQ12, and the results were verified by Western blot analysis. In conclusion, our findings have scientific significance for the application of flavonoids in preventive and therapeutic strategies for PM2.5-associated pulmonary diseases and for the promotion of human health.

Tumour-specific amplitude-modulated radiofrequency electromagnetic fields induce differentiation of hepatocellular carcinoma via targeting Cav3.2 T-type voltage-gated calcium channels and Ca2+ influx.

BACKGROUND: Administration of amplitude modulated 27·12 MHz radiofrequency electromagnetic fields (AM RF EMF) by means of a spoon-shaped applicator placed on the patient's tongue is a newly approved treatment for advanced hepatocellular carcinoma (HCC). The mechanism of action of tumour-specific AM RF EMF is largely unknown. METHODS: Whole body and organ-specific human dosimetry analyses were performed. Mice carrying human HCC xenografts were exposed to AM RF EMF using a small animal AM RF EMF exposure system replicating human dosimetry and exposure time. We performed histological analysis of tumours following exposure to AM RF EMF. Using an agnostic genomic approach, we characterized the mechanism of action of AM RF EMF. FINDINGS: Intrabuccal administration results in systemic delivery of athermal AM RF EMF from head to toe at levels lower than those generated by cell phones held close to the body. Tumour shrinkage results from differentiation of HCC cells into quiescent cells with spindle morphology. AM RF EMF targeted antiproliferative effects and cancer stem cell inhibiting effects are mediated by Ca2+ influx through Cav3·2 T-type voltage-gated calcium channels (CACNA1H) resulting in increased intracellular calcium concentration within HCC cells only. INTERPRETATION: Intrabuccally-administered AM RF EMF is a systemic therapy that selectively block the growth of HCC cells. AM RF EMF pronounced inhibitory effects on cancer stem cells may explain the exceptionally long responses observed in several patients with advanced HCC. FUND: Research reported in this publication was supported by the National Cancer Institute's Cancer Centre Support Grant award number P30CA012197 issued to the Wake Forest Baptist Comprehensive Cancer Centre (BP) and by funds from the Charles L. Spurr Professorship Fund (BP). DWG is supported by R01 AA016852 and P50 AA026117.

On-off-on fluorescent carbon dots from waste tea: Their properties, antioxidant and selective detection of CrO42-, Fe3+, ascorbic acid and L-cysteine in real samples.

In this work, we reported an economical plant-based hydrothermal method for one-pot green synthesis of water-soluble carbon dots (Tea-CDs) by using waste tea extract as a carbon source. The synthesized Tea-CDs were characterized by UV-visible, fluorescence, FT-IR, TEM, XPS and XRD. The Tea-CDs were found to remove hydroxyl and superoxide anion radical in vitro. In addition, the Tea-CDs exhibited bright blue fluorescence under UV-light (λex = 365 nm), and the fluorescence could be effectively quenched by CrO42- and Fe3+ ions. Meanwhile, the fluorescence of Tea-CDs-CrO42- and Tea-CDs-Fe3+ systems could be again easily recovered by ascorbic acid (AA) and L-cysteine (L-Cys). As an on-off-on fluorescent nano-sensor of the Tea-CDs, the sensitive detection of CrO42-, Fe3+, AA and L-Cys were all performed, showing that the good linear relationships between fluorescence intensity of Tea-CDs and concentration of all testing samples. Finally, the sensors successfully detected CrO42-, Fe3+, AA and L-Cys in commercially available real samples with satisfactory recovery ranges. The prepared sensors offer distinct advantages including low cost, simple handling, good sensitivity and high selectivity.

[Studies on constituents of Polygonum multiflorum extract in vivo and in vitro based on UPLC-Q-TOF-MS].

To explore the drug-induced constituents in vivo of Polygonum multiflorum extract (PM). This study was the first to study the drug-induced constituents in target organ liver. Agilent MassHunter qualitative analysis software and Metabolite ID software were applied for the analysis of retention time, exact relative molecular mass, primary and secondary mass spectrum information based on ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and targeted-MS/MS. By comparison with literature and standards, a total of 5 prototypes and 6 metabolites were identified or tentatively elucidated from the liver samples. In addition, the drug-induced constituents in plasma and PM were also analyzed in this study and 8 prototypes and 19 metabolites were detected from the plasma samples, while 30 compounds were detected from the extract of PM. Emodin oxidative acetylation metabolites, hydroxyl methylation metabolites, carboxylation glucuronidation metabolites and ketone glucuronidation metabolites in this study were first reported. Through the comparative analysis between the in vivo and in vitro constituents of PM, the study preliminarily revealed the drug-induced constituents (prototypes and metabolites) in liver and clarified the transfer process and transmutation rules of constituents in PM, blood and liver, which would further deepen our understanding on constituents of PM in vivo.

Anti-complementary constituents of Anchusa italica.

Activity-guided fractionation for complement inhibitors led to the isolation of 24 known compounds from Anchusa italica. Chemical types include eight megastigmane compounds, five triterpenoid compounds, five lignan compounds, three flavonoid compounds, two alkaloid compounds and one phenthyl alcohol compound. Among which, a lignan (medioresinol), an alkaloid (5-hydroxypyrrolidin-2-one) and a flavonoid (5-hydroxyl-3', 4', 6, 7-tetramethoxy flavone) exhibited better anticomplementary effects with CH50 values ranging from 0.07 to 0.82 mM, which are plausible candidates for developing potent anticomplementary agents.

A new oleanolic-type triterpene glycoside from Anchusa italica.

A new oleanolic-type triterpene glycoside, (3ß,21ß)-21-[(ß-d-glucopyranosyl-(1→2)-ß-d-glucopyranosyl)oxy]-3-hydroxyolean-12-en-28-oic acid (1), together with five analogues, oleanazuroside 1 (2), oleanazuroside 2 (3), 24-hydroxytormentic acid ester glucoside (4), 24-epi-pinfaensin (5), and oleanolic acid 3-O-α-l-arabinoside (6) were isolated from the n-butyl alcohol extract of Anchusa italica. Their structures were determined spectroscopically and compared with previously reported spectral data. Compounds 3-4 and 6 were evaluated for their cytotoxic activities against five human cancer cell lines, but only compound 6 showed moderate cytotoxicity.

Water-soluble acacetin prodrug confers significant cardioprotection against ischemia/reperfusion injury.

The morbidity and mortality of patients with ischemic cardiomyopathy resulted from ischemia/reperfusion injury are very high. The present study investigates whether our previously synthesized water-soluble phosphate prodrug of acacetin was cardioprotective against ischemia/reperfusion injury in an in vivo rat model. We found that intravenous administration of acacetin prodrug (10 mg/kg) decreased the ventricular arrhythmia score and duration, reduced ventricular fibrillation and infarct size, and improved the impaired heart function induced by myocardial ischemia/reperfusion injury in anesthetized rats. The cardioprotective effects were further confirmed with the parent compound acacetin in an ex vivo rat regional ischemia/reperfusion heart model. Molecular mechanism analysis revealed that acacetin prevented the ischemia/reperfusion-induced reduction of the anti-oxidative proteins SOD-2 and thioredoxin, suppressed the release of inflammation cytokines TLR4, IL-6 and TNFα, and decreased myocyte apoptosis induced by ischemia/reperfusion. Our results demonstrate the novel evidence that acacetin prodrug confer significant in vivo cardioprotective effect against ischemia/reperfusion injury by preventing the reduction of endogenous anti-oxidants and the release of inflammatory cytokines, thereby inhibiting cardiomyocytes apoptosis, which suggests that the water-soluble acacetin prodrug is likely useful in the future as a new drug candidate for treating patients with acute coronary syndrome.

Curcumin Protects Neurons from Glutamate-Induced Excitotoxicity by Membrane Anchored AKAP79-PKA Interaction Network.

Now stimulation of AMPA receptor as well as its downstream pathways is considered as potential central mediators in antidepressant mechanisms. As a signal integrator which binds to AMPA receptor, A-kinase anchoring protein 79-(AKAP79-) PKA complex is regarded as a potential drug target to exert neuroprotective effects. A well-tolerated and multitarget drug curcumin has been confirmed to exert antidepressant-like effects. To explore whether AKAP79-PKA complex is involved in curcumin-mediated antiexcitotoxicity, we detected calcium signaling, subcellular location of AKAP79-PKA complex, phosphorylation of glutamate receptor, and ERK and AKT cascades. In this study, we found that curcumin protected neurons from glutamate insult by reducing Ca(2+) influx and blocking the translocation of AKAP79 from cytomembrane to cytoplasm. In parallel, curcumin enhanced the phosphorylation of AMPA receptor and its downstream pathways in PKA-dependent manner. If we pretreated cells with PKA anchoring inhibitor Ht31 to disassociate PKA from AKAP79, no neuroprotective effects were observed. In conclusion, our results show that AKAP79-anchored PKA facilitated the signal relay from AMPA receptor to AKT and ERK cascades, which may be crucial for curcumin-mediated antiexcitotoxicity.

[Cryopreservation study on seeds and embryos in Dalbergia odorifera].

The mature seeds and excised embryos of Dalbergia odorifera were used as materials to study the effect of moisture content on their survival, as well as the effect of rapid freezing and vitrification freezing method on seeds and in vitro embryos cryopreservation. The results showed that the germination rate and vigor decreased from 82.67%, 85% to 18.35%, 25% respectively, when the seed moisture content decreased from 15.04% to 8.14%; and the germination rate decreased from 82.67% to 37.50%, 25.37% respectively by vitrification freezing method and rapid freezing method, when the seed moisture content decreased from 15.04% to 9.37%. Among all the moisture content gradient, 12.35% moisture reached the maximal germination rate, which were 63.58% and 50.45% respectively by vitrification freezing and rapid freezing; and when the embryo moisture content was 26.32%, the germination rate decreased from 95.67% to 58.31% and 33.82% respectively by vitrification freezing and rapid freezing. And when the moisture content was in the range of 14.17% -21.34%, the germination rate was a bit of decrease. The experiment results showed that the optimum conditions of seed cryopreservation were: moisture content 12.35%, vitrification freezing; and the optimum conditions of in vitro embryo cryopreservation were: moisture 15.04%, vitrification freezing. In conclusion, the effects of moisture content on germination rate after cryopreservation in D. odorifera seeds and embryo were significant, and vitrification freezing method is much better than rapid freezing method.

Photothermolysis of lymphatic endothelial cells by gold nanoshell-mediated hyperthermia.

Tumor-associated lymphatics and lymphangiogenesis have been shown to play important roles in promoting tumor growth and metastasis. However, the lymphatic system has received much less attention as a target of intervention in cancer treatment compared to the blood vascular system. In this study, we explored the feasibility of photothermal therapy targeting the lymphatic system as a strategy for inhibiting lymphatics-mediated tumor metastasis. Specifically, photothermolysis of lymphatic endothelial cells (LECs) via gold nanoshell-mediated hyperthermia was investigated. Near-Infrared-absorbing Au nanoshells (AuNSs) were synthesized and used as the photothermal coupling agent. After 24-hr incubation, significant amount of the AuNSs were taken up by murine simian virus lymphatic endothelial cells with minimal cytotoxicity. Thermally-induced injury to LECs was found to occur above a threshold temperature of 46 degrees C. Preliminary data also suggested apoptosis as the mechanism of thermally-induced cell death in this temperature range. In a proof-of-concept experiment, AuNS-mediated photothermal heating was found to induce cell death in statistically higher percent of LECs incubated with AuNSs after 15-min laser irradiation compared to the controls. We believed that the findings in this study represent the first step in developing AuNS-mediated photothermal therapy as a potential strategy to disrupt tumor-associated lymphatics.

Allitridi inhibits multiple cardiac potassium channels expressed in HEK 293 cells.

Allitridi (diallyl trisulfide) is an active compound (volatile oil) from garlic. The previous studies reported that allitridi had anti-arrhythmic effect. The potential ionic mechanisms are, however, not understood. The present study was designed to determine the effects of allitridi on cardiac potassium channels expressed in HEK 293 cells using a whole-cell patch voltage-clamp technique and mutagenesis. It was found that allitridi inhibited hKv4.3 channels (IC(50) = 11.4 µM) by binding to the open channel, shifting availability potential to hyperpolarization, and accelerating closed-state inactivation of the channel. The hKv4.3 mutants T366A, T367A, V392A, and I395A showed a reduced response to allitridi with IC(50)s of 35.5 µM, 44.7 µM, 23.7 µM, and 42.4 µM. In addition, allitridi decreased hKv1.5, hERG, hKCNQ1/hKCNE1 channels stably expressed in HEK 293 cells with IC(50)s of 40.2 µM, 19.6 µM and 17.7 µM. However, it slightly inhibited hKir2.1 current (100 µM, inhibited by 9.8% at -120 mV). Our results demonstrate for the first time that allitridi preferably blocks hKv4.3 current by binding to the open channel at T366 and T367 of P-loop helix, and at V392 and I395 of S6 domain. It has a weak inhibition of hKv1.5, hERG, and hKCNQ1/hKCNE1 currents. These effects may account for its anti-arrhythmic effect observed in experimental animal models.

[Phytoplankton' s community structure and its relationships with environmental factors in an aquaculture lake, Datong Lake of China].

From December 2008 to October 2009, a seasonal investigation was conducted on the phytoplankton' s community structure and its relationships with environmental factors in Datong Lake. With the comparison of the historical data in 1960, the potential effects of intensive aquaculture on the aquatic environment were analyzed, aimed to provide theoretical support for the sustainable fishery of freshwater lakes. A total of 98 phytoplankton species belonging to 7 phyla and 54 genera were collected, among which, Peridinium bipes, Chroomonas acuta, Chlorella vulgaris, Crytomonas ovate, Cyclotella meneghiniana, Crytomonas erosa, Anabaena circinalis, Microcystis aeruginosa, and Anabaena azotica were the dominant species, and had obvious seasonal variations. The mean annual cell density of the phytoplankton was 1.84 x 10(6) cells x L(-1), being the highest in summer (16.4 x 10(6) cells x L(-1)) and ranged from 1.71 x 10(6) to 1.98 x 10(6) cells x L(-1) in the other three seasons. The values of the abundance index, Shannon index, and Pielou index of the phytoplankton community were 2.01-4.55, 1.26-2.69, and 0.69-1.27, respectively. Canonical correlation analysis (CCA) showed that water depth, water temperature, transparency, and water total phosphorus content, oxidation-reduction potential, and electrical conductivity were the main environmental factors affecting the phytoplankton community structure in the Lake.

From fragment screening to in vivo efficacy: optimization of a series of 2-aminoquinolines as potent inhibitors of beta-site amyloid precursor protein cleaving enzyme 1 (BACE1).

Using fragment-based screening of a focused fragment library, 2-aminoquinoline 1 was identified as an initial hit for BACE1. Further SAR development was supported by X-ray structures of BACE1 cocrystallized with various ligands and molecular modeling studies to expedite the discovery of potent compounds. These strategies enabled us to integrate the C-3 side chain on 2-aminoquinoline 1 extending deep into the P2' binding pocket of BACE1 and enhancing the ligand's potency. We were able to improve the BACE1 potency to subnanomolar range, over 10(6)-fold more potent than the initial hit (900 µM). Further elaboration of the physical properties of the lead compounds to those more consistent with good blood-brain barrier permeability led to inhibitors with greatly improved cellular activity and permeability. Compound 59 showed an IC(50) value of 11 nM on BACE1 and cellular activity of 80 nM. This compound was advanced into rat pharmacokinetic and pharmacodynamic studies and demonstrated significant reduction of Aß levels in cerebrospinal fluid (CSF).