Recent advances in C(sp3)-N bond formation via metallaphoto-redox catalysis.

The C(sp3)-N bond is ubiquitous in natural products, pharmaceuticals, biologically active molecules and functional materials. Consequently, the development of practical and efficient methods for C(sp3)-N bond formation has attracted more and more attention. Compared to the conventional ionic pathway-based thermal methods, photochemical processes that proceed through radical mechanisms by merging photoredox and transition-metal catalyses have emerged as powerful and alternative tools for C(sp3)-N bond formation. In this review, recent advances in the burgeoning field of C(sp3)-N bond formation via metallaphotoredox catalysis have been highlighted. The contents of this review are categorized according to the transition metals used (copper, nickel, cobalt, palladium, and iron) together with photocatalysis. Emphasis is placed on methodology achievements and mechanistic insight, aiming to inspire chemists to invent more efficient radical-involved C(sp3)-N bond-forming reactions.

Restoring colistin sensitivity in colistin-resistant Salmonella and Escherichia coli: combinatorial use of berberine and EDTA with colistin.

The appearance and prevalence of multidrug-resistance (MDR) Gram-negative bacteria (GNB) have limited our antibiotic capacity to control bacterial infections. The clinical efficacy of colistin (COL), considered as the "last resort" for treating GNB infections, has been severely hindered by its increased use as well as the emergence and prevalence of mobile colistin resistance (MCR)-mediated acquired drug resistance. Identifying promising compounds to restore antibiotic activity is becoming an effective strategy to alleviate the crisis of increasing MDR. We first demonstrated that the combination of berberine (BBR) and EDTA substantially restored COL sensitivity against COL-resistant Salmonella and Escherichia coli. Molecular docking indicated that BBR can interact with MCR-1 and the efflux pump system AcrAB-TolC, and BBR combined with EDTA downregulated the expression level of mcr-1 and tolC. Mechanically, BBR combined with EDTA could increase bacterial membrane damage, inhibit the function of multidrug efflux pump, and promote oxidative damage, thereby boosting the action of COL. In addition, transcriptome analysis found that the combination of BBR and EDTA can accelerate the tricarboxylic acid cycle, inhibit cationic antimicrobial peptide (CAMP) resistance, and attenuate Salmonella virulence. Notably, the combination of BBR and EDTA with COL significantly reduced the bacterial load in the liver and spleen of a mice model infected with Salmonella. Our findings revealed that BBR and EDTA can be used as adjuvants collectively with COL to synergistically reverse the COL resistance of bacteria. IMPORTANCE: Colistin is last-resort antibiotic used to treat serious clinical infections caused by MDR bacterial pathogens. The recent emergence of transferable plasmid-mediated COL resistance gene mcr-1 has raised the specter of a rapid worldwide spread of COL resistance. Coupled with the fact of barren antibiotic development pipeline nowadays, a critical approach is to revitalize existing antibiotics using antibiotic adjuvants. Our research showed that berberine combined with EDTA effectively reversed COL resistance both in vivo and in vitro through multiple modes of action. The discovery of berberine in combination with EDTA as a new and safe COL adjuvant provides a therapeutic regimen for combating Gram-negative bacteria infections. Our findings provide a potential therapeutic option using existing antibiotics in combination with antibiotic adjuvants and address the prevalent infections caused by MDR Gram-negative pathogens worldwide.

Role of clinical pharmacists in multidisciplinary collaborative management of blood glucose in COVID-19 patients with hyperglycemia.

BACKGROUND: During the ongoing global pandemic of COVID-19, the association between hyperglycemia and COVID-19 infection has emerged as a notable concern. Therefore, finding effective methods to manage hyperglycemia in patients with COVID-19 is crucial. OBJECTIVE: To introduce the clinical pharmacists participating in multidisciplinary collaborative whole hospital blood glucose management mode, and to explore its effect on blood glucose control in patients with coronavirus disease 2019 infection and complicated with hyperglycemia. METHODS: Patients with COVID-19 treated at Nanjing Drum Tower Hospital from December 2022 to January 2023 were assigned to routine diagnosis and treatment group and whole hospital blood glucose management group according to the blood glucose management plan received by patients. The groups were compared in regards to their adherence to management advice, blood glucose levels, fluctuation, inflammation-related indicators, medical service-related indicators, and incidence of hypoglycemia and adverse events. RESULTS: After 5 days of glucose management, both groups showed a decrease in fasting and postprandial blood glucose. Postprandial blood glucose in the whole hospital glucose management group was significantly lower than the routine group (P < 0.05). The whole hospital glucose management group showed a significant increase in compliance rate, improved inflammation-related indicators, and higher detection rates for hemoglobin and islet function (P < 0.05). Implementation rates for medical orders and treatment plans were also higher in the whole hospital group (P < 0.05). There was no significant difference in incidence of adverse events. CONCLUSIONS: Multidisciplinary blood glucose management is highly recommended for patients with COVID-19 who have hyperglycemia due to its effectiveness, standardization, safety, and improvement of inflammation indicators.

Potentiation of the lateral habenula-ventral tegmental area pathway underlines the susceptibility to depression in mice with chronic pain.

Chronic pain often develops severe mood changes such as depression. However, how chronic pain leads to depression remains elusive and the mechanisms determining individuals' responses to depression are largely unexplored. Here we found that depression-like behaviors could only be observed in 67.9% of mice with chronic neuropathic pain, leaving 32.1% of mice with depression resilience. We determined that the spike discharges of the ventral tegmental area (VTA)-projecting lateral habenula (LHb) glutamatergic (Glu) neurons were sequentially increased in sham, resilient and susceptible mice, which consequently inhibited VTA dopaminergic (DA) neurons through a LHbGlu-VTAGABA-VTADA circuit. Furthermore, the LHbGlu-VTADA excitatory inputs were dampened via GABAB receptors in a pre-synaptic manner. Regulation of LHb-VTA pathway largely affected the development of depressive symptoms caused by chronic pain. Our study thus identifies a pivotal role of the LHb-VTA pathway in coupling chronic pain with depression and highlights the activity-dependent contribution of LHbGlu-to-VTADA inhibition in depressive behavioral regulation.

[A new xanthone from hulls of Garcinia mangostana and its cytotoxic activity].

Eight compounds were isolated from ethyl acetate fraction of 80% ethanol extract of the hulls of Garcinia mangostana by silica gel, Sephadex LH-20 column chromatography, as well as prep-HPLC methods. By HR-ESI-MS, MS, 1D and 2D NMR spectral analyses, the structures of the eight compounds were identified as 16-en mangostenone E(1), α-mangostin(2), 1,7-dihydroxy-2-(3-methy-lbut-2-enyl)-3-methoxyxanthone(3), cratoxyxanthone(4), 2,6-dimethoxy-para-benzoquinone(5), methyl orselinate(6), ficusol(7), and 4-(4-carboxy-2-methoxyphenoxy)-3,5-dimethoxybenzoic acid(8). Compound 1 was a new xanthone, and compound 4 was a xanthone dimer, compound 5 was a naphthoquinone. All compounds were isolated from this plant for the first time except compounds 2 and 3. Cytotoxic bioassay suggested that compounds 1, 2 and 4 possessed moderate cytotoxicity, suppressing HeLa cell line with IC_(50) va-lues of 24.3, 35.5 and 17.1 µmol·L~(-1), respectively. Compound 4 also could suppress K562 cells with an IC_(50) value of 39.8 µmol·L~(-1).

[Characteristics and Health Risk Assessment of Volatile Organic Compounds in Different Functional Zones in Baoji in Summer].

The situation of air pollution in Guanzhong Plain has been increasing in recent years; hence, it is very important to study the characteristics of volatile organic compounds (VOCs) and their health risks in urban functional zones. We analyzed 115 VOCs using gas chromatography-mass spectrometry/hydrogen ion flame detector (GC-MS/FID) and high performance liquid chromatography (HPLC) at four sampling sites in the traffic, comprehensive, industrial, and scenic zones of Baoji. We analyzed the main components and key species in the different functional zones. Ozone formation potential (OFP),·OH consumption rate (L·OH), and secondary organic aerosol formation potential (SOAFP) were used to evaluate the environmental impact, and the hazard index (HI) and lifetime cancer risk (LCR) methods were employed. The results revealed that the mean values of φ(TVOCs) in the traffic, comprehensive, industrial, and scenic zones were (59.63±23.85)×10-9, (42.92±11.88)×10-9, (60.27±24.09)×10-9, and (55.54±7.44)×10-9, respectively. The dominant contributors at the traffic zone were alkanes, and those at the other functional zones were OVOCs. Acetaldehyde, acetone, n-butane, and isopentane were abundant at different functional zones. According to the characteristic ratios of VOCs, the average ratio of toluene to benzene (T/B) at the traffic, comprehensive, industrial, and scenic zones were 1.84, 2.39, 1.28, and 1.64, respectively, and the ratio of iso-pentane to n-pentane (i/n) was mainly between 1 and 4. The results indicated that VOCs in Baoji were significantly affected by vehicle emissions and gasoline evaporation, biomass and coal combustion, and industrial coatings and foundry. The ratio of m/p-xylene to ethylbenzene (X/E) was lower than 2 at the four functional zones, and the minimum was 1.79 at the scenic zones; the results revealed that X/E was small, and the aging degree of air masses was high, indicating the influence of regional transport. According to the ratio of formaldehyde to acetaldehyde (C1/C2) and the ratio of acetaldehyde to propanal (C2/C3), it was suggested that there may have been evident anthropogenic emission sources, and the photochemical reaction had an important effect on aldehydes and ketones. Environmental impact assessment results revealed that OVOCs and alkenes contributed significantly to OFP and OFP from large to small was as follows:industrial zone>scenic zone>traffic zone>comprehensive zone. The range of L·OH in each functional zone was 8.77-15.82 s-1, with isoprene contributing the most in the industrial zone and acetaldehyde contributing the most at other functional zones. The SOAFP of each functional zone was as follows:scenic zone>comprehensive zone>traffic zone>industrial zone. Toluene, m/p-xylene, and isoprene were the notable species. According to the health risk assessment of EPA, the HI of toxic VOCs in all functional zones was lower than 1, which was at an acceptable level. However, the number of days with HI>1 in industrial zones accounted for 42.86% of the total sampling days, indicating a high risk. The lifetime carcinogenic risk (LCR) of the traffic, comprehensive, industrial, and scenic zones were 1.83×10-5, 1.21×10-5, 1.85×10-5, and 1.63×10-5, respectively, which were all in grade Ⅲ of the rating system, indicating a high probability of cancer risk. Species with LCR greater than 10-6 were formaldehyde; acetaldehyde; 1,2-dibromoethane; 1,2-dichloroethane; 1,2-dichloropropane; and chloroform.

Proanthocyanidins induce analgesic and anxiolytic effects in spared nerve injured mice by decreasing in vivo firing rate of pyramidal cells in the insular cortex.

Neuropathic pain is one of the most common symptoms of clinical pain that often accompanied by severe emotional changes such as anxiety. However, the treatment for comorbidity of chronic pain and anxiety is limited. Proanthocyanidins (PACs), a group of polyphenols enriched in plants and foods, have been reported to cause pain-alleviating effects. However, whether and how PACs induce analgesic and anxiolytic effects in the central nervous system remain obscure. In the present study, we observed that microinjection of PACs into the insular cortex (IC) inhibited mechanical and spontaneous pain sensitivity and anxiety-like behaviors in mice with spared nerve injury. Meanwhile, PACs application exclusively reduced the FOS expression in the pyramidal cells but not interneurons in the IC. In vivo electrophysiological recording of the IC further showed that PACS application inhibited the firing rate of spikes of pyramidal cells of IC in neuropathic pain mice. In summary, PACs induce analgesic and anxiolytic effects by inhibiting the spiking of pyramidal cells of the IC in mice with neuropathic pain, which should provide new evidence of PACs as the potential clinical treatment of chronic pain and anxiety comorbidity.

[Effect of guarana on lipid metabolism in obese rats: a study based on lipidomics].

This study investigated the effect of guarana on plasma lipid metabolites in obese rats and analyzed its mechanism in the treatment of dyslipidemia in obesity. High-fat diet was used to establish obese rat models, and the therapeutic effect of guarana on obese rats was evaluated by measuring body weight, white fat, liver weight, and lipid content, as well as observing liver histomorphology. Lipid metabolites in plasma of rats in each group were detected by UHPLC-Q-TOF-MS lipidomics. The protein expressions of fatty acid synthase, acetyl-CoA carboxylase 1, triglyceride synthesis enzyme, carnitine palmitoyltransferase Ⅰ, and acetyl-coenzyme A acyltransferase 2 in rat liver were detected using Western blot. The results revealed that guarana significantly reduced body weight, white fat, and liver weight of obese rats due to high-fat diet, and alleviated dyslipidemia and liver steatosis. Lipidomics showed that some triglycerides and phospholipids were significantly elevated in the high-fat model group, and part of them was reduced after guarana treatment. Western blot found that guarana inhibited the expression of hepatic fatty acid and triglyceride synthesis-related proteins and increased the expression of fatty acid ß-oxidation-related proteins. Abnormalities in triglyceride and phospholipid metabolism are the main characteristics of plasma lipid metabolism in obese rats induced by high-fat diet. Guarana may regulate partial triglyceride and phospholipid metabolism by inhibiting hepatic fatty acid and triglyceride synthesis and increasing fatty acid ß-oxidation, thereby improving rat obesity and dyslipidemia.

Implementation of a motivational programme based on existence- relatedness-growth theory in nursing undergraduate interns: A quasi-experimental study.

BACKGROUND: Currently, a paramount issue in nursing education is to motivate nursing undergraduate interns to develop self-directed learning skills and improve their practice satisfaction and professional identity, so as to meet the growing demands in healthcare. OBJECTIVES: This study aimed to examine the effectiveness of a motivational programme based on the Existence-Relatedness-Growth (ERG) theory in developing self-directed learning skills, improving practice satisfaction and promoting the professional identity of nursing undergraduate interns in China. DESIGN: A quasi-experimental study design. SETTING: A government-funded tertiary teaching hospital in Guangzhou, Guangdong province, China. METHODS: This study was conducted with 99 nursing undergraduate interns in a hospital between June 2020 and April 2022. The interns in the experimental group (n = 50) participated in the motivational programme based on ERG theory, while those in the control group (n = 49) underwent a traditional training programme. The interns in the two groups were compared in terms of their degree of self-directed learning, practice satisfaction and professional identity after the training, using independent samples t-test. RESULTS: After the internship, interns in the experimental group showed a statistically significantly higher level of self-directed learning and practice satisfaction than those in the control group (p < 0.05). However, no significant difference was observed in professional identity between the two groups after the internship. CONCLUSIONS: The motivational programme based on ERG theory was shown to be effective in improving self-directed learning and practice satisfaction in nursing undergraduate interns. A large-scale randomized controlled trial is warranted to confirm the results.

Analysis of Regulatory Mechanism of AcrB and CpxR on Colistin Susceptibility Based on Transcriptome and Metabolome of Salmonella Typhimurium.

With the increasing and inappropriate use of colistin, the emerging colistin-resistant isolates have been frequently reported during the last few decades. Therefore, new potential targets and adjuvants to reverse colistin resistance are urgently needed. Our previous study has confirmed a marked increase of colistin susceptibility (16-fold compared to the wild-type Salmonella strain) of cpxR overexpression strain JSΔacrBΔcpxR::kan/pcpxR (simplified as JSΔΔ/pR). To searching for potential new drug targets, the transcriptome and metabolome analysis were carried out in this study. We found that the more susceptible strain JSΔΔ/pR displayed striking perturbations at both the transcriptomics and metabolomics levels. The virulence-related genes and colistin resistance-related genes (CRRGs) were significantly downregulated in JSΔΔ/pR. There were significant accumulation of citrate, α-ketoglutaric acid, and agmatine sulfate in JSΔΔ/pR, and exogenous supplement of them could synergistically enhance the bactericidal effect of colistin, indicating that these metabolites may serve as potential adjuvants for colistin therapy. Additionally, we also demonstrated that AcrB and CpxR could target the ATP and reactive oxygen species (ROS) generation, but not proton motive force (PMF) production pathway to potentiate antibacterial activity of colistin. Collectively, these findings have revealed several previously unknown mechanisms contributing to increased colistin susceptibility and identified potential targets and adjuvants for potentiating colistin treatment of Salmonella infections. IMPORTANCE Emergence of multidrug-resistant (MDR) Gram-negative (G-) bacteria have led to the reconsideration of colistin as the last-resort therapeutic option for health care-associated infections. Finding new drug targets and strategies against the spread of MDR G- bacteria are global challenges for the life sciences community and public health. In this paper, we demonstrated the more susceptibility strain JSΔΔ/pR displayed striking perturbations at both the transcriptomics and metabolomics levels and revealed several previously unknown regulatory mechanisms of AcrB and CpxR on the colistin susceptibility. Importantly, we found that exogenous supplement of citrate, α-ketoglutaric acid, and agmatine sulfate could synergistically enhance the bactericidal effect of colistin, indicating that these metabolites may serve as potential adjuvants for colistin therapy. These results provide a theoretical basis for finding potential new drug targets and adjuvants.

[Characteristics and Source Apportionment of Volatile Organic Compounds in Zhanjiang in Summer].

Ozone pollution is intensifying in China, and its related studies are weak in non-focus regions and non-focus cities. Here, we investigated the characteristics and sources of volatile organic compounds (VOCs) at three sampling sites in Zhanjiang. We analyzed 101 VOCs using a gas chromatography-mass spectrometry/hydrogen ion flame detector (GC-MS/FID) and high-performance liquid chromatography (HPLC) using a Summa canister and DNPH adsorption tube. We calculated the ozone formation potential (OFP) of VOCs and used the positive matrix factorization (PMF) model for source apportionment. The results showed that the mean φ(TVOCs) was 1.28×10-7, and the dominant contributors were OVOCs (52%), followed by alkanes (36%), alkenes (7%), halogenated hydrocarbons (2.42%), aromatic hydrocarbons (1.61%), and alkynes (0.78%). The diurnal variation in VOCs was influenced by photochemical reactions; the ratio of aromatic hydrocarbons and alkanes was high in the morning and evening and low at noon, whereas OVOCs had a low ratio in the morning and noon and high in the evening, influenced by primary emissions and the upwind transport of pollutants. The OFP was 3.28×10-7, and the dominant species were formaldehyde, butene, n-butane, butanone, and acetaldehyde.The analysis of X/E values (characterizing the aging degree of air masses) and backward trajectories of air masses showed that during the sampling, when influenced by air masses from the south or southwest, X/E was small, and the aging degree of air masses was high, indicating the influence of regional transport; when influenced by air masses from the east or southeast direction, X/E was large, and the air masses were fresh, and VOCs were mainly from local emissions. Six emission sources of VOCs, including industrial emissions, gasoline vehicle exhaust and gasoline evaporation, regional background and transport sources, biomass combustion, diesel vehicles and marine shipping emissions, and solvent use emission sources, were resolved using the PMF model, with contributions of 36.05%, 28.99%, 13.84%, 10.13%, 7.05%, and 3.95%, respectively.Zhanjiang should strengthen the supervision of formaldehyde, butene, n-butane and butanone, industry sources, and mobile sources as the focus of control.

Anti-aging Effects of Alu Antisense RNA on Human Fibroblast Senescence Through the MEK-ERK Pathway Mediated by KIF15.

OBJECTIVE: To investigate whether human short interspersed nuclear element antisense RNA (Alu antisense RNA; Alu asRNA) could delay human fibroblast senescence and explore the underlying mechanisms. METHODS: We transfected Alu asRNA into senescent human fibroblasts and used cell counting kit-8 (CCK-8), reactive oxygen species (ROS), and senescence-associated beta-galactosidase (SA-ß-gal) staining methods to analyze the anti-aging effects of Alu asRNA on the fibroblasts. We also used an RNA-sequencing (RNA-seq) method to investigate the Alu asRNA-specific mechanisms of anti-aging. We examined the effects of KIF15 on the anti-aging role induced by Alu asRNA. We also investigated the mechanisms underlying a KIF15-induced proliferation of senescent human fibroblasts. RESULTS: The CCK-8, ROS and SA-ß-gal results showed that Alu asRNA could delay fibroblast aging. RNA-seq showed 183 differentially expressed genes (DEGs) in Alu asRNA transfected fibroblasts compared with fibroblasts transfected with the calcium phosphate transfection (CPT) reagent. The KEGG analysis showed that the cell cycle pathway was significantly enriched in the DEGs in fibroblasts transfected with Alu asRNA compared with fibroblasts transfected with the CPT reagent. Notably, Alu asRNA promoted the KIF15 expression and activated the MEK-ERK signaling pathway. CONCLUSION: Our results suggest that Alu asRNA could promote senescent fibroblast proliferation via activation of the KIF15-mediated MEK-ERK signaling pathway.

Alu antisense RNA ameliorates methylglyoxal-induced human lens epithelial cell apoptosis by enhancing antioxidant defense.

AIM: To determine whether an antisense RNA corresponding to the human Alu transposable element (Aluas RNA) can protect human lens epithelial cells (HLECs) from methylglyoxal-induced apoptosis. METHODS: Cell counting kit-8 (CCK-8) and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays were used to assess HLEC viability. HLEC viability/death was detected using a Calcein-AM/PI double staining kit; the annexin V-FITC method was used to detect HLEC apoptosis. The cytosolic reactive oxygen species (ROS) levels in HLECs were determined using a reactive species assay kit. The levels of malondialdehyde (MDA) and the antioxidant activities of total-superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) were assessed in HLECs using their respective kits. RT-qPCR and Western blotting were used to measure mRNA and protein expression levels of the genes. RESULTS: Aluas RNA rescued methylglyoxal-induced apoptosis in HLECs and ameliorated both the methylglyoxal-induced decrease in Bcl-2 mRNA and the methylglyoxal-induced increase in Bax mRNA. In addition, Aluas RNA inhibited the methylglyoxal-induced increase in Alu sense RNA expression. Aluas RNA inhibited the production of ROS induced by methylglyoxal, restored T-SOD and GSH-Px activity, and moderated the increase in MDA content after treatment with methylglyoxal. Aluas RNA significantly restored the methylglyoxal-induced down-regulation of Nrf2 gene and antioxidant defense genes, including glutathione peroxidase, heme oxygenase 1, γ-glutamylcysteine synthetase and quinone oxidoreductase 1. Aluas RNA ameliorated methylglyoxal-induced increases of the mRNA and protein expression of Keap1 that is the negative regulator of Nrf2. CONCLUSION: Aluas RNA reduces apoptosis induced by methylglyoxal by enhancing antioxidant defense.

In Vitro Hypoglycemic Diterpenoids from the Roots of Croton yunnanensis.

Fifteen compounds including nine new diterpenes were isolated from the roots of Croton yunnanensis. By HRESIMS, NMR, ECD data, and X-ray diffraction analysis, the new compounds were characterized as eight neo-clerodane diterpenes (compounds 1-8) and one 15,16-dinor-ent-pimarane diterpene (9). All diterpenes were assayed for their hypoglycemic activities. Compounds 1-4, 6, 7, and 10 promoted glucose uptake activity in insulin-resistant 3T3-L1 adipocytes. Compounds 1 and 6 showed insulin sensitizing activity, potentiating conspicuously their glucose uptake activity at a concentration of 20 µM when treated synergistically with low-concentration insulin at 1 nM.

Classification of major depressive disorder using an attention-guided unified deep convolutional neural network and individual structural covariance network.

Major depressive disorder (MDD) is the second leading cause of disability worldwide. Currently, the structural magnetic resonance imaging-based MDD diagnosis models mainly utilize local grayscale information or morphological characteristics in a single site with small samples. Emerging evidence has demonstrated that different brain structures in different circuits have distinct developmental timing, but mature coordinately within the same functional circuit. Thus, establishing an attention-guided unified classification framework with deep learning and individual structural covariance networks in a large multisite dataset could facilitate developing an accurate diagnosis strategy. Our results showed that attention-guided classification could improve the classification accuracy from primary 75.1% to ultimate 76.54%. Furthermore, the discriminative features of regional covariance connectivities and local structural characteristics were found to be mainly located in prefrontal cortex, insula, superior temporal cortex, and cingulate cortex, which have been widely reported to be closely associated with depression. Our study demonstrated that our attention-guided unified deep learning framework may be an effective tool for MDD diagnosis. The identified covariance connectivities and structural features may serve as biomarkers for MDD.

Synergistic antibacterial activity of baicalin and EDTA in combination with colistin against colistin-resistant Salmonella.

The emergence and rapid spread of multidrug resistant (MDR) Gram-negative bacteria have posed a serious threat to global health and security. Because of the time-consuming, high cost and high risk of developing new antibiotics, a significant method is to use antibiotic adjuvants to revitalize the existing antibiotics. The purpose of the study is to research the traditional Chinese medicine baicalin with the function of inhibiting the efflux pump and EDTA whether their single or combination can increase the activity of colistin against colistin-resistant Salmonella in vitro and in vivo, and to explore its molecular mechanisms. In vitro antibacterial experiments, we have observed that baicalin and EDTA alone could enhance the antibacterial activity of colistin. At the same time, the combination of baicalin and EDTA also showed a stronger synergistic effect on colistin, reversing the colistin resistance of all Salmonella strains. Molecular docking and RT-PCR results showed that the combination of baicalin and EDTA not only affected the expression of mcr-1, but also was an effective inhibitor of MCR-1. In-depth synergistic mechanism analysis revealed that baicalin and EDTA enhanced colistin activity through multiple pathways, including accelerating the tricarboxylic acid cycle (TCA cycle), inhibiting the bacterial antioxidant system and lipopolysaccharide (LPS) modification, depriving multidrug efflux pump functions and attenuating bacterial virulence. In addition, the combinational therapy of colistin, baicalin and EDTA displayed an obvious reduction in bacterial loads cfus of liver and spleen compared with monotherapy and 2-drug combination therapy. In conclusion, our study indicates that the combination of baicalin and EDTA as a novel colistin adjuvant can provide a reliable basis for formulating the therapeutic regimen for colistin resistant bacterial infection.

[Chemical constituents from Salacia polysperma].

Nine compounds were isolated from the 90% ethanol extract of Salacia polysperma by silica gel, Sephadex LH-20 column chromatography, together with preparative HPLC methods. Based on HR-ESI-MS, MS, 1D and 2D NMR spectral analyses, the structures of the nine compounds were identified as 28-hydroxy wilforlide B(1), wilforlide A(2), 1ß,3ß-dihydroxyurs-9(11),12-diene(3),(-)-epicatechin(4),(+)-catechin(5),(-)-4'-O-methyl-ent-galloepicatechin(6), 3-hydroxy-1-(4-hydroxy-3-methoxy-phenyl)propan-1-one(7),(-)-(7S,8R)-4-hydroxy-3,3',5'-trimethoxy-8',9'-dinor-8,4'-oxyneoligna-7,9-diol-7'-aldehyde(8), and vanillic acid(9). Compound 1 is a new oleanane-type triterpene lactone. Compounds 1, 3, 4, 7-9 were isolated from the Salacia genus for the first time. All compounds were assayed for their α-glucosidase inhibitory activity. The results suggested that compound 8 exhibited moderate α-glucosidase inhibitory activity, with an IC_(50) value of 37.2 µmol·L~(-1), and the other compounds showed no α-glucosidase inhibitory activity.

Effect of guarana on lipid metabolism in obese rats: a study based on lipidomics / 中国中药杂志

This study investigated the effect of guarana on plasma lipid metabolites in obese rats and analyzed its mechanism in the treatment of dyslipidemia in obesity. High-fat diet was used to establish obese rat models, and the therapeutic effect of guarana on obese rats was evaluated by measuring body weight, white fat, liver weight, and lipid content, as well as observing liver histomorphology. Lipid metabolites in plasma of rats in each group were detected by UHPLC-Q-TOF-MS lipidomics. The protein expressions of fatty acid synthase, acetyl-CoA carboxylase 1, triglyceride synthesis enzyme, carnitine palmitoyltransferase Ⅰ, and acetyl-coenzyme A acyltransferase 2 in rat liver were detected using Western blot. The results revealed that guarana significantly reduced body weight, white fat, and liver weight of obese rats due to high-fat diet, and alleviated dyslipidemia and liver steatosis. Lipidomics showed that some triglycerides and phospholipids were significantly elevated in the high-fat model group, and part of them was reduced after guarana treatment. Western blot found that guarana inhibited the expression of hepatic fatty acid and triglyceride synthesis-related proteins and increased the expression of fatty acid β-oxidation-related proteins. Abnormalities in triglyceride and phospholipid metabolism are the main characteristics of plasma lipid metabolism in obese rats induced by high-fat diet. Guarana may regulate partial triglyceride and phospholipid metabolism by inhibiting hepatic fatty acid and triglyceride synthesis and increasing fatty acid β-oxidation, thereby improving rat obesity and dyslipidemia.

Unveiling the functional and evolutionary landscape of RNA editing in chicken using genomics and transcriptomics.

The evolutionary and functional features of RNA editing are well studied in mammals, cephalopods, and insects, but not in birds. Here, we integrated transcriptomic and whole-genomic analyses to exhaustively characterize the expansive repertoire of adenosine-to-inosine (A-to-I) RNA editing sites (RESs) in the chicken. In addition, we investigated the evolutionary status of the chicken editome as a potential mechanism of domestication. We detected the lowest editing level in the liver of chickens, compared to muscles in humans, and found higher editing activity and specificity in the brain than in non-neural tissues, consistent with the brain's functional complexity. To a certain extent, specific editing activity may account for the specific functions of tissues. Our results also revealed that sequences critical to RES secondary structures remained conserved within avian evolution. Furthermore, the RNA editome was shaped by purifying selection during chicken domestication and most RESs may have served as a selection pool for a few functional RESs involved in chicken domestication, including evolution of nervous and immune systems. Regulation of RNA editing in chickens by adenosine deaminase acting on RNA (ADAR) enzymes may be affected by non-ADAR factors whose expression levels changed widely after ADAR knockdown. Collectively, we provide comprehensive lists of candidate RESs and non-ADAR-editing regulators in the chicken, thus contributing to our current understanding of the functions and evolution of RNA editing in animals.

Activation of cholinergic basal forebrain neurons improved cognitive functions in adult-onset hypothyroid mice.

Cognitive dysfunction is common in hypothyroid patients, even after undergoing sufficient levothyroxine (LT4) replacement therapy for euthyroid. Our previous studies indicated that cholinergic neurons might contribute to the decline of cognition in adult-onset hypothyroidism. Nevertheless, the role of the cellular and neural control of basal forebrain (BF) cholinergic neurons in hypothyroidism-induced cognitive impairments is unknown. Using transgenic mice that specifically expressed chemogenetic activators in their BF cholinergic neurons, we systematically investigated the role of BF cholinergic neurons in hypothyroidism-induced cognitive dysfunction by the combined approaches of patch clamp electrophysiology, behavioral testing, and immunohistochemistry. The results showed that LT4 treatment in the adult-onset hypothyroid mice reversed only 78 % of the BF cholinergic neurons to their normal values of electrophysiological properties. LT4 monotherapy did not rehabilitate cognitive function in the hypothyroid mice. Chemogenetic selective activation of the BF cholinergic neurons combined with LT4 treatment significantly improved learning and memory functions in the hypothyroid mice. In addition, chemogenetic activation of the cholinergic neurons induced the robust expression of c-Fos protein in the BF, prefrontal cortex (PFC), and hippocampus. This indicated that the BF cholinergic neurons improved learning and memory functions in the hypothyroid mice via the BF-PFC and BF-hippocampus pathways. In the hypothyroid C57BL/6 J mice, combined treatment via LT4 and donepezil, a cholinesterase inhibitor, significantly increased cognitive functions. The results suggested that the BF cholinergic neurons are critical for regulating learning and memory and reveal a novel pathophysiological mechanism for hypothyroidism-induced cognitive impairments.