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1.
J Nutr ; 154(2): 369-380, 2024 02.
Article in English | MEDLINE | ID: mdl-38122845

ABSTRACT

BACKGROUND: There is a U-shaped relationship between dietary selenium (Se) ingestion and optimal sperm quality. OBJECTIVES: This study aimed to investigate the optimal dietary dose and forms of Se for sperm quality of breeder roosters and the relevant mechanisms. METHODS: In experiment 1, 18-wk-old Jingbai laying breeder roosters were fed a Se-deficient base diet (BD, 0.06 mg Se/kg), or the BD + 0.1, 0.2, 0.3, 0.4, 0.5, or 1.0 mg Se/kg for 9 wk. In experiment 2, the roosters were fed the BD or the BD + sodium selenite (SeNa), seleno-yeast (SeY), or Se-nanoparticles (SeNPs) at 0.2 mg Se/kg for 9 wk. RESULTS: In experiment 1, added dietary 0.2 and 0.3 mg Se/kg led to higher sperm motility and lower sperm mortality than the other groups at weeks 5, 7, and/or 9. Furthermore, added dietary 0.2-0.4 mg Se/kg produced better testicular histology and/or lower testicular 8-hydroxy-deoxyguanosine than the other groups. Moreover, integrated testicular transcriptomic and cecal microbiomic analysis revealed that inflammation, cell proliferation, and apoptosis-related genes and bacteria were dysregulated by Se deficiency or excess. In experiment 2, compared with SeNa, SeNPs slightly increased sperm motility throughout the experiment, whereas SeNPs slightly reduced sperm mortality compared with SeY at week 9. Both SeY and SeNPs decreased malondialdehyde in the serum than those of SeNa, and SeNPs led to higher glutathione peroxidase (GPX) and thioredoxin reductase activities and GPX1 and B-cell lymphoma 2 protein concentrations in the testis compared with SeY and SeNa. CONCLUSIONS: The optimal dietary Se dose for reproductive health of breeder roosters is 0.25-0.35 mg Se/kg, and SeNPs displayed better effects on reproductive health than SeNa and SeY in laying breeder roosters. The optimal doses and forms of Se maintain reproductive health of roosters associated with regulation intestinal microbiota homeostasis and/or testicular redox balance, inflammation, cell proliferation, and apoptosis.


Subject(s)
Gastrointestinal Microbiome , Selenium , Male , Animals , Testis/metabolism , Selenium/metabolism , Chickens/metabolism , Reproductive Health , Sperm Motility , Seeds , Oxidation-Reduction , Diet , Inflammation/metabolism , Apoptosis , Cell Proliferation , Dietary Supplements
2.
Bioorg Chem ; 144: 107107, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38218069

ABSTRACT

Dibenzofurans are a small class of natural products with versatile biological activities that used to be thought to come mainly from lichens and ascomycetes. In fact, they are also distributed widely in higher plants, especially in the families Rosaceae and Myrtaceae. Dibenzofurans and derivatives from lichens and ascomycetes have been well reviewed, but dibenzofurans from all biological sources in nature have not been reviewed. In this review, dibenzofurans from all natural sources have been comprehensively reviewed, and a total of 211 dibenzofurans isolated and identified from organisms between 1843 and March 2023 are categorized and discussed, including their biosynthesis, structural diversity, sources, and bioactivities.


Subject(s)
Ascomycota , Lichens , Humans , Dibenzofurans , Lichens/chemistry
3.
Chemistry ; 29(57): e202301338, 2023 Oct 13.
Article in English | MEDLINE | ID: mdl-37498677

ABSTRACT

The study of C2 Al4 -/0 and C2 Al5 -/0 was conducted using anion photoelectron spectroscopy and quantum chemical computations. The present findings reveal that C2 Al4 - has a boat-like structure, with a single C2 unit surrounded by four aluminum atoms. In contrast, the neutral C2 Al4 species adopts a D2h planar structure with two planar tetracoordinate carbon (ptC) units, consistent with previous reports. Furthermore, the global minimum isomer of C2 Al5 - adopts a D3h symmetry, where the C2 unit interacts with five aluminum atoms. It was also found that a lower symmetry structure of C2 Al5 - , where all five aluminum atoms are located on the same side of the C2 unit, albeit slightly higher in energy compared to the D3h structure. These computations show that the D3h structure of C2 Al5 - is highly stable, exhibiting a large HOMO-LUMO gap.

4.
J Phys Chem A ; 126(33): 5621-5631, 2022 Aug 25.
Article in English | MEDLINE | ID: mdl-35972885

ABSTRACT

Carbon-doped aluminum cluster anions, AlnC- (n = 6-15), were generated by laser vaporization and investigated by mass-selected anion photoelectron spectroscopy. The geometric structures of AlnC- (n = 6-15) anions were determined by the comparison of theoretical calculations with the experimental results. It is found that the most stable structure of Al6C- is a carbon endohedral triangular prism. The Al7C- anion is a magic cluster with high stability. The structures of Al7-9C- can be viewed as the additional aluminum atoms attached around the triangular prism Al6C-. Two isomers of Al10C- have been detected in the experiments. The most stable one has a planar tetracoordinate carbon structure. The second one derives from Al9C- with the carbon atom located in a pentagonal bipyramid. The Al11C- anion has a bilayer structure composed of one planar tetracoordinate carbon and one aluminum-centered hexagon, in which the major interactions between two layers are multicenter bonds. The structures of Al12-14C- can be viewed as evolving from Al11C- by adding aluminum atoms to interact with the carbon atom. In Al15C-, the carbon atom stays at the surface with a tetracoordinate structure, and an icosahedral Al13 unit can be identified as a part of the geometric structure of Al15C-.

5.
Planta Med ; 88(13): 1190-1198, 2022 Oct.
Article in English | MEDLINE | ID: mdl-34875697

ABSTRACT

Phloridzin is a lead compound of the prestigious antidiabetic gliflozins. The present study found that phloridzin highly accumulated in Malus rockii Rehder. The content of phloridzin in M. rockii was the highest among wild plants, with the percentage of 15.54% in the dry leaves. The structure of phloridzin was revised by proton exchange experiments and extensive 2D NMR spectra. Phloridzin exhibited significant hypolipidemic activity in golden Syrian hamsters maybe by increasing the expression of CYP7A1, at the doses of 50 mg/kg and 200 mg/kg. The total performance of anti-hyperlipidemic effect of phloridzin may be superior to that of lovastatin, though lovastatin was more active than phloridzin. In addition, phloridzin exhibited moderate antimalarial activity with inhibition ratio of 31.3 ± 10.9% at a dose of 25 mg/kg/day, and showed moderate analgesic activity with 28.0% inhibition at a dose of 50 mg/kg.


Subject(s)
Antimalarials , Malus , Sodium-Glucose Transporter 2 Inhibitors , Phlorhizin/pharmacology , Phlorhizin/chemistry , Malus/chemistry , Sodium-Glucose Transporter 2 Inhibitors/metabolism , Protons , Lovastatin/metabolism
6.
Anim Biotechnol ; : 1-13, 2022 Nov 30.
Article in English | MEDLINE | ID: mdl-36449378

ABSTRACT

The Forkhead box factor 1 (FoxO1) gene plays a vital role in the growth and development of skeletal muscle. In the present study, expression analysis of the bovine FoxO1 gene exhibited the highest expression in longissimus dorsi muscle followed by its expression in adipose tissue. Moreover, high mRNA expression of FoxO1 gene was found in differentiated bovine myoblasts and adipocytes at day 6 of induced differentiation (p < 0.05). The regulatory pattern of the bovine FoxO1 gene was investigated through screening and dual-luciferase activity of the 1.7 kb 5'UTR (untranslated region) within pGL3-basic vector and a core promoter region was explored at (-285/-27) upstream of the transcription start site. The transcription factors (TFs) MEF2A and HOXA5 within the core promoter region (-285/-27) were found as the regulatory cis-acting element. The siRNA interference of the TFs, chromatin immunoprecipitation (ChIP) assay, and site-directed mutation validated that MEF2A and HOXA5 binding occurs in the region -285/-27 bp and performs an essential role in the transcriptional regulation of bovine FoxO1 gene. These findings explored the regulatory network mechanism of the FoxO1 gene in skeletal muscle development and adipogenesis for the bovine breed improvement program.

7.
Phys Chem Chem Phys ; 23(3): 1967-1975, 2021 Jan 28.
Article in English | MEDLINE | ID: mdl-33470255

ABSTRACT

The AlnC5- (n = 1-5) clusters were detected in the gas-phase and were investigated via mass-selected anion photoelectron spectroscopy. The structures of AlnC5-/0 (n = 1-5) were explored by theoretical calculations. It is found that the structures of AlC5-/0 and Al2C5-/0 are linear while those of Al3C5-/0, Al4C5-/0, and Al5C5-/0 are two-dimensional. The most stable structures of AlC5-/0 and Al2C5-/0 are linear with the Al atoms attached to the ends of C5 chain. The most stable structures of Al3C5-/0 can be viewed as three Al atoms interacting with a nonlinear C5 chain. The most stable structure of Al4C5- anion is a planar structure composed of a C2 unit, a C3 unit, and two Al2 units, while that of the neutral Al4C5 cluster has four Al atoms connected to different positions of a distorted C5 chain. The global minimum structures of Al5C5-/0 are planar structures composed of an Al4C quadrilateral, two C2 groups, and an Al atom connected to two C2 groups. Planar tetracoordinate carbon (ptC) has been identified in the structures of both anionic and neutral Al5C5. It is worth mentioning that the star-like structure of Al5C5- is slightly higher in energy than the ground state structure. The comparison of theoretical calculations with the experimental spectra indicates the star-like structure of Al5C5- may also appear in our experiments.

8.
J Phys Chem A ; 125(1): 302-307, 2021 Jan 14.
Article in English | MEDLINE | ID: mdl-33393298

ABSTRACT

Anion photoelectron spectroscopy and theoretical calculations were used to investigate the structural and bonding properties of Al4C6-/0 clusters. The vertical detachment energy of Al4C6- was measured to be 3.36 ± 0.08 eV. The structure of the Al4C6- anion is confirmed to be a bowl-shaped distorted triangle with an Al atom at the center and three Al atoms at the vertices. The global minimum isomer of neutral Al4C6 has a planar triangle-shaped structure with D3h symmetry. Both anionic and neutral Al4C6 have a hexacoordinated Al atom surrounded by three C≡C groups. Compared with the structure of neutral Al4C6, the structure of Al4C6- is distorted due to the addition of the excess electron. The molecular orbital analysis shows that the singly occupied molecular orbital of Al4C6- mainly locates on one side of the triangle plane and the neutral Al4C6 has a large highest occupied molecular orbital and lowest unoccupied molecular orbital gap. Theoretical calculations indicate that neutral Al4C6 has some aromaticity.

9.
Int J Med Sci ; 18(4): 964-974, 2021.
Article in English | MEDLINE | ID: mdl-33456354

ABSTRACT

Endothelial cell proliferation disorder caused by vascular injury seems to be one of the causes of atherosclerosis, which is the pathological basis of coronary heart disease. The role of STAT3 in the regulation of microRNAs and endothelial dysfunction in atherosclerosis is unclear. STAT3 can be activated by cytokine IL-6 and up regulate the expression of CX3CL1. In addition, microRNA-15a-5p (miR-15a-5p) inhibited the transcription of CX3CL1, the proliferation of vascular endothelial cells and the proliferation of STAT3 regulated vascular endothelial cells. STAT3 positively regulates the expression of CX3CL1, and then down-regulates the inhibition of CX3CL1 by over-expression of miR-15a-5p, thus forming an elimination feedback loop to control the proliferation of HUVECs and affect the progression of atherosclerosis. In conclusion, miR-15a-5p may be the therapeutic target of the pathological basis of coronary atherosclerosis.


Subject(s)
Atherosclerosis/genetics , Chemokine CX3CL1/genetics , Endothelium, Vascular/pathology , MicroRNAs/metabolism , STAT3 Transcription Factor/metabolism , Animals , Atherosclerosis/blood , Atherosclerosis/pathology , Cell Line , Cell Movement/genetics , Cell Proliferation/genetics , Chemokine CX3CL1/blood , Chemokine CX3CL1/metabolism , Disease Models, Animal , Down-Regulation , Endothelium, Vascular/cytology , Feedback, Physiological , Human Umbilical Vein Endothelial Cells , Humans , Mice, Knockout, ApoE , MicroRNAs/genetics , STAT3 Transcription Factor/genetics , Up-Regulation , Vascular Endothelial Growth Factor A/blood , Vascular Endothelial Growth Factor A/metabolism
10.
J Asian Nat Prod Res ; 23(8): 789-795, 2021 Aug.
Article in English | MEDLINE | ID: mdl-32614662

ABSTRACT

A new prenylated coumestan, campylohirtin A (1), along with fifteen phenolic known compounds (2‒16) and four other known compounds (17‒20), was obtained from the 95% ethanol extract of roots of Campylotropis hirtella. Their structures were elucidated based on extensive spectroscopic analysis (1 D and 2 D-NMR, MS, UV and IR). In vitro antimalarial activities of compounds 1-3, 5-14 and 16 were evaluated by ß-hematin formation inhibition assay. Compared with the positive control chloroquine diphosphate, compounds 8, 11 and 16 exhibited strong antimalarial activity with the IC50 values of 69.9, 33.2 and 75.4 µM, respectively. Compounds 1-3, 5-7 and 12 showed moderate antimalarial activities with IC50 values ranging from 134.6 µM to 578.6 µM.[Formula: see text].


Subject(s)
Chrysobalanaceae , Fabaceae , Coumarins , Molecular Structure , Plant Roots
11.
J Cell Biochem ; 121(5-6): 3392-3405, 2020 06.
Article in English | MEDLINE | ID: mdl-31904151

ABSTRACT

Although many methods and new therapeutic drugs have been developed, the overall survival rate and long-term survival rate of patients with gastric cancer (GC) are still not satisfactory. In this study, we investigated the effects of microRNA miR-133a-3p and transcription factor FOXP3 on proliferation and autophagy of GC cells and their interactions. Our results showed that knockdown of FOXP3 increased the proliferation and autophagy of GC cells. The relationship between FOXP3 and autophagy has not been reported previously. In addition, FOXP3 could directly bind the promoter region of TP53 and inhibit its expression. miR-133a-3p increased the proliferation and autophagy via decreasing the protein level of FOXP3 by targeting its 3'-UTR. Our research provides new insights into the development of GC and provides new ideas and theoretical basis for the clinical treatment of GC and the development of new drug targets.


Subject(s)
Autophagy , Cell Proliferation , Forkhead Transcription Factors/metabolism , Gene Expression Regulation, Neoplastic , MicroRNAs/metabolism , Stomach Neoplasms/metabolism , 3' Untranslated Regions , Biomarkers, Tumor/metabolism , Cell Line, Tumor , Cytoplasm/metabolism , Humans , Promoter Regions, Genetic
12.
Biochem Cell Biol ; 98(3): 396-404, 2020 06.
Article in English | MEDLINE | ID: mdl-31800303

ABSTRACT

Prostate cancer (PCa) is the second leading cause of death in men, and current studies have shown that circular RNAs (circRNAs) play important roles in its occurrence and development. Detection of circRNAs in PCa cells showed that circ_KATNAL1 is down-regulated, mainly located in the cytoplasm, and contains multiple binding sites of miR-145-3p, which is an anticancer miRNA. RNA immunoprecipitation with anti-AGO2 antibody, RNA pull-down assays with biotin-labeled circ_KATNAL1 probe or an miR-145-3p mimic, and dual luciferase reporter gene assays confirmed that circ_KATNAL1 binds directly to miR-145-3p in cells, and that WISP1, which is highly expressed in many types of tumors, is an important target gene of miR-145-3p. Circ_KATNAL1 and miR-145-3p promote each other's expression, and down-regulate the expression of the target gene WISP1. Both circ_KATNAL1 and miR-145-3p inhibit cell proliferation, invasiveness, and migration, down-regulate the expression of MMP-2 and MMP-9, promote cell apoptosis and the activation of caspase-3, caspase-8, caspase-9, and PARP, whereas WISP1 has the opposite effect, and the above-mentioned functions of circ_KATNAL1 were achieved through the miR-145-3p/WISP1 pathway. Therefore, circ_KATNAL1 plays an anticancer role in PCa cells through the miR-145-3p/WISP1 pathway, which could be an important target for the diagnosis and treatment of PCa.


Subject(s)
CCN Intercellular Signaling Proteins/metabolism , Gene Expression Regulation, Neoplastic , Katanin/metabolism , MicroRNAs/metabolism , Prostatic Neoplasms/metabolism , Proto-Oncogene Proteins/metabolism , RNA, Circular/metabolism , Antineoplastic Agents/pharmacology , Apoptosis , Binding Sites , Cell Line, Tumor , Cell Movement , Cell Nucleus/metabolism , Cell Proliferation , Cytoplasm/metabolism , Humans , Immunoprecipitation , Male , Neoplasm Invasiveness
13.
PLoS Pathog ; 14(6): e1007061, 2018 06.
Article in English | MEDLINE | ID: mdl-29879225

ABSTRACT

Suppression of HIV replication by antiretroviral therapy (ART) or host immunity can prevent AIDS but not other HIV-associated conditions including neurocognitive impairment (HIV-NCI). Pathogenesis in HIV-suppressed individuals has been attributed to reservoirs of latent-inducible virus in resting CD4+ T cells. Macrophages are persistently infected with HIV but their role as HIV reservoirs in vivo has not been fully explored. Here we show that infection of conventional mice with chimeric HIV, EcoHIV, reproduces physiological conditions for development of disease in people on ART including immunocompetence, stable suppression of HIV replication, persistence of integrated, replication-competent HIV in T cells and macrophages, and manifestation of learning and memory deficits in behavioral tests, termed here murine HIV-NCI. EcoHIV established latent reservoirs in CD4+ T lymphocytes in chronically-infected mice but could be induced by epigenetic modulators ex vivo and in mice. In contrast, macrophages expressed EcoHIV constitutively in mice for up to 16 months; murine leukemia virus (MLV), the donor of gp80 envelope in EcoHIV, did not infect macrophages. Both EcoHIV and MLV were found in brain tissue of infected mice but only EcoHIV induced NCI. Murine HIV-NCI was prevented by antiretroviral prophylaxis but once established neither persistent EcoHIV infection in mice nor NCI could be reversed by long-acting antiretroviral therapy. EcoHIV-infected, athymic mice were more permissive to virus replication in macrophages than were wild-type mice, suffered cognitive dysfunction, as well as increased numbers of monocytes and macrophages infiltrating the brain. Our results suggest an important role of HIV expressing macrophages in HIV neuropathogenesis in hosts with suppressed HIV replication.


Subject(s)
CD4-Positive T-Lymphocytes/virology , Disease Reservoirs , HIV Infections/complications , HIV/physiology , Macrophages, Peritoneal/virology , Neurocognitive Disorders/virology , Adoptive Transfer , Aged , Animals , Anti-Retroviral Agents/therapeutic use , Brain/virology , Female , HIV/genetics , HIV/immunology , HIV/pathogenicity , HIV Infections/drug therapy , Humans , Male , Mice , Mice, Inbred C57BL , Mice, Nude , Middle Aged , Plasmids , Spleen/cytology , Spleen/immunology
14.
Cell Commun Signal ; 18(1): 107, 2020 07 09.
Article in English | MEDLINE | ID: mdl-32646440

ABSTRACT

BACKGROUND: Foxp3+CD4+ regulatory T cells (Treg) constitutes a key event in autoimmune diseases. STAT5b is the critical link between the IL-2/15 and FOXP3, the master regulator of Treg cells. METHODS: The CD3+T cell and Foxp3+CD4+ regulatory T cells were overexpressioned or knockdown MKL-1 and STAT5a and tested for Treg cell development and function. Direct interaction of MKL-1 and STAT5a were analyzed by coimmunoprecipitation assays, Luciferase assay, Immunofluoresence Staining and Yeast two-hybrid screening. The effect of MKL-1 and STAT5a on the Treg genes expression was analyzed by qPCR and western blotting and Flow cytometry. RESULTS: However, the molecular mechanisms mediating STAT5b-dependent Treg genes expression and Treg cell phenotype and function in autoimmune diseases are not well defined. Here, we report that the MKL-1 is a coactivator for the major Treg genes transcription factor STAT5b, which is required for human Treg cell phenotype and function. The N terminus of STAT5b, which contains a basic coiled-coil protein-protein interaction domain, binds the C-terminal activation domain of MKL-1 and enhances MKL-1 mediated transcriptional activation of Treg-specific, CArG containing promoters, including the Treg-specific genes Foxp3. Suppression of endogenous STAT5b expression by specific small interfering RNA attenuates MKL-1 transcriptional activation in cultured human cells. The STAT5b-MKL-1 interaction identifies a role of Treg-specific gene regulation and regulated mouse Treg cell development and function and suggests a possible mechanism for the protective effects of autoimmune disease Idiopathic Thrombocytopenic Purpura (ITP). CONCLUSIONS: Our studies demonstrate for the first time that MKL-1 is a coactivator for STAT5b, the regulator of Treg cell development and function. Video abstract.


Subject(s)
STAT5 Transcription Factor/metabolism , T-Lymphocytes, Regulatory/immunology , Trans-Activators/metabolism , Amides/pharmacology , Base Sequence , Biomarkers/metabolism , CD3 Complex/metabolism , Cell Nucleus/drug effects , Cell Nucleus/metabolism , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/metabolism , Humans , Interleukin-2/metabolism , Interleukin-2 Receptor alpha Subunit/metabolism , Janus Kinase 3/metabolism , Lymphocyte Count , Phosphorylation/drug effects , Promoter Regions, Genetic/genetics , Protein Binding/drug effects , Protein Domains , Purpura, Thrombocytopenic, Idiopathic/immunology , Pyridines/pharmacology , STAT5 Transcription Factor/chemistry , Serum Response Factor/metabolism , Signal Transduction/drug effects , Trans-Activators/chemistry , Tyrphostins/pharmacology , rhoA GTP-Binding Protein/metabolism
15.
Cell Biol Int ; 44(4): 1037-1045, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31903637

ABSTRACT

The occurrence and development of prostate cancer (PCa) is complex, and the related mechanism is not fully understood. Current studies have found that extracellular vesicles (EVs) and circular RNAs (circRNAs) have important functions in various tumours and other diseases. In this study, the detection of circRNAs in PCa showed that circ_SLC19A1 was increased in PCa cells and their secreted EVs. EVs with high expression of circ_SLC19A1 could be taken up by PCa cells, which promoted cell proliferation and invasion. The sequence of circ_SLC19A1 contained multiple binding sites for miR-497, and circ_SLC19A1 could bind directly to miR-497 in cells. The expression of miR-497 was downregulated in PCa cells, while the expression of its target gene septin 2 (SEPT2) was upregulated significantly. Transfection of circ_SLC19A1 small interfering RNA (siRNA) or miR-497 mimics could significantly inhibit the expression of SEPT2 and the phosphorylation of extracellular signal-regulated kinase 1 and 2 (ERK1/2). After co-transfection of circ_SLC19A1 siRNA and miR-497 inhibitors or SEPT2 overexpression vector, the expression of SEPT2 and ERK1/2 phosphorylation levels showed no significant changes. Similar results were obtained with co-transfection of miR-497 mimics and the SEPT2 overexpression vector. Therefore, cancer cells can regulate the expression of SEPT2 through miR-497 by secreting EVs with high expression of circ_SLC19A1, thus affecting the activation of the downstream ERK1/2 pathway and ultimately regulating PCa cell growth and invasion. Therefore, EV-derived circ_SLC19A1 plays an important regulatory role in PCa and may be an important target for PCa prevention and treatment.


Subject(s)
Extracellular Vesicles/physiology , Prostatic Neoplasms/metabolism , RNA, Circular/genetics , Reduced Folate Carrier Protein/genetics , Cell Line, Tumor , Cell Movement , Cell Proliferation , Gene Expression Regulation, Neoplastic , Humans , Male , MicroRNAs/metabolism , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Septins/metabolism
16.
J Nat Prod ; 83(4): 927-936, 2020 04 24.
Article in English | MEDLINE | ID: mdl-32233487

ABSTRACT

Eleven new angeloylated eudesmane sesquiterpenoids, dobinins D-N (2, 3, 5, 6, 8, 9, and 11-15), and four known compounds (1, 4, 7, and 10) were isolated from the roots of Dobinea delavayi. A new oxidation product (8a) was also obtained from dobinin H (8). Their structures were elucidated by spectroscopic data and single-crystal X-ray diffraction analyses. Dobinins K-N (12-15) are the first examples of rearrangement noreudesmane analogue sesquiterpenoids with a unique 6/5-fused carbon skeleton. A putative biosynthetic pathway of compounds 12-15 is proposed. Compound 12 exhibited significant antimalarial activity superior to artemisinin with the inhibition ratio of 59.1%, and compounds 3, 5, and 15 exhibited moderate antimalarial activities against Plasmodium yoelii BY265RFP with inhibition ratios ranging from 14.5% to 18.5% at a dose of 30 mg/kg/day. In addition, the apoptosis of P. yoelii BY265RFP by the depolarization of mitochondrial membrane potential with striking ROS production, after parasitized erythrocyte lysis mediated by cytokines IL-12 and IFN-γ, may be a possible mechanism of antimalarial action of compound 12 against P. yoelii BY265RFP.


Subject(s)
Anacardiaceae/chemistry , Antimalarials/chemistry , Antimalarials/pharmacology , Sesquiterpenes, Eudesmane/chemistry , Sesquiterpenes, Eudesmane/pharmacology , Animals , Apoptosis/drug effects , Cytokines/physiology , Erythrocytes/parasitology , Malaria/drug therapy , Malaria/parasitology , Membrane Potential, Mitochondrial/drug effects , Mice , Molecular Structure , Plant Extracts/chemistry , Plant Roots/chemistry , Plasmodium yoelii/drug effects , Reactive Oxygen Species/metabolism , X-Ray Diffraction
17.
Bioorg Chem ; 95: 103488, 2020 01.
Article in English | MEDLINE | ID: mdl-31884146

ABSTRACT

Dodelates A-E (1-5), five angeloylated eudesmane sesquiterpenoid dimers were isolated from the roots of Dobinea delavayi. Their structures were elucidated by extensive spectroscopic data and single-crystal X-ray diffraction analyses. A possible biosynthetic pathway of these five compounds was proposed. Compounds 1 and 3 exhibited moderate antimalarial activities against Plasmodium yoelii BY265RFP.


Subject(s)
Antimalarials/pharmacology , Malaria/drug therapy , Plants, Medicinal/chemistry , Plasmodium yoelii/drug effects , Sapindaceae/chemistry , Sesquiterpenes, Eudesmane/pharmacology , Animals , Antimalarials/chemistry , Antimalarials/isolation & purification , Crystallography, X-Ray , Dose-Response Relationship, Drug , Mice , Mice, Inbred Strains , Models, Molecular , Molecular Structure , Parasitic Sensitivity Tests , Plant Roots/chemistry , Sesquiterpenes, Eudesmane/chemistry , Sesquiterpenes, Eudesmane/isolation & purification , Structure-Activity Relationship
18.
J Asian Nat Prod Res ; 22(6): 594-600, 2020 Jun.
Article in English | MEDLINE | ID: mdl-31045439

ABSTRACT

A new lignan glycoside, astrayunoside A (1), along with eight known compounds (2-9), were obtained from the methanol extract of roots of Astragalus yunnanensis. All the compounds were obtained from A. yunnanensis for the first time. Their structures were elucidated by extensive spectroscopic analysis (1D and 2D-NMR, MS, UV, CD, and IR). The weak antibacterial activities of the crude extracts of A. yunnanensis against Staphyloccocus aureus, Escherichia coli, Proteus vulgaris, Pseudomonas aeruginosa, Shigella dysenteriae, Salmonella typhi H901, Candida albicans, Streptococcus mutans, and Actinomyces viscosus were observed.


Subject(s)
Lignans , Plant Extracts , Anti-Bacterial Agents , Glycosides , Microbial Sensitivity Tests , Molecular Structure
19.
J Chem Phys ; 150(7): 074304, 2019 Feb 21.
Article in English | MEDLINE | ID: mdl-30795662

ABSTRACT

The structural and electronic properties of MnCn - (n = 3-10) clusters have been investigated using size-selected photoelectron spectroscopy and density functional theory calculations. The vertical detachment energies of MnCn - exhibit a strong odd-even alternation with increasing number of carbon atoms: the vertical detachment energies of MnCn - containing even number of carbon atoms are higher than those of adjacent ones containing odd number of carbon atoms. The theoretical analyses indicate that the spin multiplicities and relative stabilities of MnCn -/0 also exhibit odd-even alternations. It is found that MnC3 - has three degenerate isomers with two linear structures in different electronic states and one fanlike structure. For n = 4-6, 8, and 10, the ground state structures are all linear with the Mn atom at one end. MnC7 - and MnC9 - have cyclic structures. As for the neutral species, MnC3 and MnC4 adopt fan-shaped structures, MnC5 has a linear structure, and MnC6-10 have cyclic configurations. The atomic dipole moment corrected Hirshfeld population analysis shows that the electrons transfer from the Mn atom to the Cn units. The total spin magnetic moments of MnCn -/0 (n = 3-10) clusters are mainly contributed by the local magnetic moments on the Mn atom.

20.
Appl Opt ; 58(2): 466-472, 2019 Jan 10.
Article in English | MEDLINE | ID: mdl-30645329

ABSTRACT

A pulse subdivision analysis method was developed to improve the spatial resolution of a conventional long pump pulse Brillouin optical time domain analysis (BOTDA) system. An exclusive photodetector was used to obtain the accurate energy distribution along the long pulse, based on which the long pulse was subdivided into several sub-pulses with certain energy weights. With these energy weights, the Brillouin spectrum generated by the long pulse was subdivided into equal numbers of sub-spectra. Each sub-spectrum could provide detailed sensing information about a fiber sub-segment related to a sub-pulse. Thus, the actual spatial resolution of the BOTDA system was determined by the sub-pulse instead of the long pulse. As a result, spatial resolution was increased by several times, depending on the subdivision multiples. The method was theoretically simulated and experimentally demonstrated. For experimental demonstration, the recognization capability of the melting point of two different fiber sections and the discrete strain distribution on a sensing fiber were respectively tested. For melting point recognization, thanks to five-multiple subdivision, a 1 m spatial resolution over 31 km sensing fiber was realized using a 50 ns pump pulse. For the strain sensing test, ten-multiple subdivision was performed to distinguish two 0.5 m stretched fiber sections with a 0.2 m interval using a 20 ns pump pulse. The spatial resolution is 0.2 m, which is a ten times' improvement compared with that before subdivision analysis. Due to its simplicity and cost-effectiveness, the method is believed to have extensive application prospects in distributed fiber sensing fields.

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