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1.
Cell ; 184(24): 5950-5969.e22, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34741801

RESUMO

The biogenesis of mammalian autophagosomes remains to be fully defined. Here, we used cellular and in vitro membrane fusion analyses to show that autophagosomes are formed from a hitherto unappreciated hybrid membrane compartment. The autophagic precursors emerge through fusion of FIP200 vesicles, derived from the cis-Golgi, with endosomally derived ATG16L1 membranes to generate a hybrid pre-autophagosomal structure, HyPAS. A previously unrecognized apparatus defined here controls HyPAS biogenesis and mammalian autophagosomal precursor membranes. HyPAS can be modulated by pharmacological agents whereas its formation is inhibited upon severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection or by expression of SARS-CoV-2 nsp6. These findings reveal the origin of mammalian autophagosomal membranes, which emerge via convergence of secretory and endosomal pathways, and show that this process is targeted by microbial factors such as coronaviral membrane-modulating proteins.


Assuntos
Autofagossomos/virologia , COVID-19/virologia , Autofagia , COVID-19/metabolismo , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Retículo Endoplasmático/metabolismo , Endossomos/fisiologia , Endossomos/virologia , Complexo de Golgi/fisiologia , Células HEK293 , Células HeLa , Humanos , Fusão de Membrana , Microscopia Confocal , Fagossomos/metabolismo , Fagossomos/virologia , Proteínas Qa-SNARE/biossíntese , Receptores sigma/biossíntese , SARS-CoV-2 , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/biossíntese , Sinaptotagminas/biossíntese , Receptor Sigma-1
2.
J Proteome Res ; 23(4): 1272-1284, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38470452

RESUMO

Gestational diabetes mellitus (GDM) with intrauterine hyperglycemia induces a series of changes in the placenta, which have adverse effects on both the mother and the fetus. The aim of this study was to investigate the changes in the placenta in GDM and its gender differences. In this study, we established an intrauterine hyperglycemia model using ICR mice. We collected placental specimens from mice before birth for histological observation, along with tandem mass tag (TMT)-labeled proteomic analysis, which was stratified by sex. When the analysis was not segregated by sex, the GDM group showed 208 upregulated and 225 downregulated proteins in the placenta, primarily within the extracellular matrix and mitochondria. Altered biological processes included cholesterol metabolism and oxidative stress responses. After stratification by sex, the male subgroup showed a heightened tendency for immune-related pathway alterations, whereas the female subgroup manifested changes in branched-chain amino acid metabolism. Our study suggests that the observed sex differences in placental protein expression may explain the differential impact of GDM on offspring.


Assuntos
Diabetes Gestacional , Hiperglicemia , Humanos , Gravidez , Feminino , Masculino , Camundongos , Animais , Placenta/metabolismo , Proteômica , Camundongos Endogâmicos ICR , Diabetes Gestacional/genética , Diabetes Gestacional/metabolismo , Hiperglicemia/genética
3.
Angew Chem Int Ed Engl ; 63(1): e202316259, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37988261

RESUMO

Macrocycles with bent π-conjugation motif are extremely rare in nature and synthetically daunting and anticancer haouamines and spirohexenolides were representative of such rare natural products with synthetically challenging bent π-conjugation within a macrocycle. While the total synthesis of haouamines has been elegantly achieved, spirohexenolides remains an unmet synthetic challenge due to the highly strained bent 1,3,5-triene conjugation within C15 macrocycle. Inspired by the chemical synthesis of cycloparaphenylenes (CPPs) and haouamines, herein we devise a synthetic strategy to overcome the highly strained bent 1,3,5-triene conjugation within the macrocycle and achieve the first, asymmetric total synthesis of spirohexenolides A (>20 mg) and B (>50 mg). Our synthesis features strategic design of ring-closing metathesis (RCM) macrocyclization followed by double dehydration to achieve the C15 macrocycle with the deformed nonplanar 1,3,5-triene conjugation. In addition, we have developed a new enantioselective construction of highly functionalized spirotetronate fragment (northeast moiety) through RCM and Ireland-Claisen rearrangement. Our in vitro bioassay studies reveal that both spirohexenolides are cytotoxic against a panel of human cancer cells with IC50 1.2-13.3 µM and spirohexenolide A is consistently more potent (up to 3 times) than spirohexenolide B, suggesting the importance of alcohol for their bioactivity and for medicinal chemistry development.

4.
Biol Reprod ; 109(1): 53-64, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37154585

RESUMO

Aerobic exercises could improve the sperm motility of obese individuals. However, the underlying mechanism has not been fully elucidated, especially the possible involvement of the epididymis in which sperm acquire their fertilizing capacity. This study aims to investigate the benefit effect of aerobic exercises on the epididymal luminal milieu of obese rats. Sprague-Dawley male rats were fed on a normal or high-fat diet (HFD) for 10 weeks and then subjected to aerobic exercises for 12 weeks. We verified that TRPA1 was located in the epididymal epithelium. Notably, aerobic exercises reversed the downregulated TRPA1 in the epididymis of HFD-induced obese rats, thus improving sperm fertilizing capacity and Cl- concentration in epididymal milieu. Ussing chamber experiments showed that cinnamaldehyd (CIN), agonist of TRPA1, stimulated an increase of the short-circuit current (ISC) in rat cauda epididymal epithelium, which was subsequently abolished by removing the ambient Cl- and HCO3-. In vivo data revealed that aerobic exercises increased the CIN-stimulated Cl- secretion rate of epididymal epithelium in obese rats. Pharmacological experiments revealed that blocking cystic fibrosis transmembrane regulator (CFTR) and Ca2+-activated Cl- channel (CaCC) suppressed the CIN-stimulated anion secretion. Moreover, CIN application in rat cauda epididymal epithelial cells elevated intracellular Ca2+ level, and thus activate CACC. Interfering with the PGHS2-PGE2-EP2/EP4-cAMP pathway suppressed CFTR-mediated anion secretion. This study demonstrates that TRPA1 activation can stimulate anion secretion via CFTR and CaCC, which potentially forming an appropriate microenvironment essential for sperm maturation, and aerobic exercises can reverse the downregulation of TRPA1 in the epididymal epithelium of obese rats.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística , Epididimo , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Epididimo/metabolismo , Dieta Hiperlipídica/efeitos adversos , Cálcio/metabolismo , Motilidade dos Espermatozoides , Sêmen/metabolismo , Canais de Cloreto/metabolismo , Canais de Cloreto/farmacologia , Ânions/metabolismo , Ânions/farmacologia , Proteínas de Transporte/metabolismo , Homeostase , Cloretos/metabolismo , Cloretos/farmacologia
5.
Acc Chem Res ; 55(16): 2326-2340, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35916456

RESUMO

The six-membered heterocycles containing oxygen and nitrogen (tetrahydropyrans, pyrans, piperidines) are among the most common heterocyclic structures ubiquitously present in bioactive molecules such as carbohydrates, small-molecule drugs, and natural products. Chemical synthesis of fully functionalized pyrans and piperidines is a research theme of practical importance and scientific significance and, thus, has attracted continuous interest from synthetic chemists. Among the numerous synthetic approaches, Achmatowicz rearrangement (AchR) represents a general and unique strategy that uses biomass-derived furfuryl alcohols as the renewable starting material to obtain fully functionalized six-membered oxygen/nitrogen heterocycles, which provides golden opportunities for organic chemists to address various synthetic challenges.This Account summarizes our 10 years of work on exploiting AchR to address some challenges in organic synthesis ranging from green chemistry and organic methodology to the total synthesis of natural products. We enabled the sustainable and safe use of AchR in a small (academia) or large (industrial) scale by developing two generations of green approaches for AchR (oxone-halide and Fenton-halide), which largely eliminate the use of the most popular, but more toxic and expansive, NBS and m-CPBA. This triggered our intensive interest in developing new green chemistry for important organic reactions, in particular, halogenation/oxidation reactions involving reactive halogenating species with the aim of eliminating the use of commonly used toxic halogen agents such as elemental bromine, chlorine gas, and various N-haloamide reagents (NBS, NCS, and NIS). We successfully employed oxone-halide and Fenton-halide as green alternatives to several mechanistically related organic reactions including arene/alkene halogenation, oxidation or oxidative rearrangement of indoles, oxidation of alcohols/thioacetals, and oxidative halogenation of aldoximes for the in situ generation of nitrile oxide. These green reactions are expected to have a solid impact on the future of organic synthesis in academia and industries.We expanded the synthetic utility of AchR by exploring several new transformations of AchR products and developed a cascade reductive ring expansion, reductive deoxygenation/Heck-Matsuda arylation, palladium-catalyzed C-arylation, and regiodivergent [3 + 2] cycloaddition with 1,3-dicarbonyls. These methodologies offer a new avenue to fully functionalized six-membered heterocycles.The synthetic utility of AchR was demonstrated in our total synthesis of 28 natural products with a pyran/piperidine moiety. The AchR-based strategy endows the total synthesis with scalability, sustainability, and flexibility. The green and scalable approaches developed in our lab for AchR allow us to easily obtain decagrams of synthetically valuable pyrans and/or piperidines with low risk and low cost from biomass-derived furfuryl alcohol/aldehyde.


Assuntos
Produtos Biológicos , Química Orgânica , Nitrogênio , Oxigênio , Piperidinas , Piranos
6.
Int J Mol Sci ; 24(4)2023 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-36834510

RESUMO

Both bioactive sphingolipids and Sigma-1 receptor (S1R) chaperones occur ubiquitously in mammalian cell membranes. Endogenous compounds that regulate the S1R are important for controlling S1R responses to cellular stress. Herein, we interrogated the S1R in intact Retinal Pigment Epithelial cells (ARPE-19) with the bioactive sphingoid base, sphingosine (SPH), or the pain-provoking dimethylated SPH derivative, N,N'-dimethylsphingosine (DMS). As informed by a modified native gel approach, the basal and antagonist (BD-1047)-stabilized S1R oligomers dissociated to protomeric forms in the presence of SPH or DMS (PRE-084 as control). We, thus, posited that SPH and DMS are endogenous S1R agonists. Consistently, in silico docking of SPH and DMS to the S1R protomer showed strong associations with Asp126 and Glu172 in the cupin beta barrel and extensive van der Waals interactions of the C18 alkyl chains with the binding site including residues in helices 4 and 5. Mean docking free energies were 8.73-8.93 kcal/mol for SPH and 8.56-8.15 kcal/mol for DMS, and calculated binding constants were ~40 nM for SPH and ~120 nM for DMS. We hypothesize that SPH, DMS, and similar sphingoid bases access the S1R beta barrel via a membrane bilayer pathway. We further propose that the enzymatic control of ceramide concentrations in intracellular membranes as the primary sources of SPH dictates availability of endogenous SPH and DMS to the S1R and the subsequent control of S1R activity within the same cell and/or in cellular environments.


Assuntos
Receptores sigma , Esfingosina , Animais , Esfingolipídeos , Ceramidas , Mamíferos/metabolismo , Receptor Sigma-1
7.
Biol Reprod ; 107(1): 196-204, 2022 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-35323884

RESUMO

In recent years, the developmental origins of diseases have been increasingly recognized and accepted. As such, it has been suggested that most adulthood chronic diseases such as diabetes, obesity, cardiovascular disease, and even tumors may develop at a very early stage. In addition to intrauterine environmental exposure, germ cells carry an important inheritance role as the primary link between the two generations. Adverse external influences during differentiation and development can cause damage to germ cells, which may then increase the risk of chronic disease development later in life. Here, we further elucidate and clarify the concept of gamete and embryo origins of adult diseases by focusing on the environmental insults on germ cells, from differentiation to maturation and fertilization.


Assuntos
Epigênese Genética , Células Germinativas , Adulto , Diferenciação Celular , Metilação de DNA , Células Germinativas/metabolismo , Humanos , Padrões de Herança , Obesidade/metabolismo
8.
Circ Res ; 126(9): 1190-1208, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32324495

RESUMO

Epigenetic mechanisms involve the placing (writing) or removal (erasing) of histone modifications that allow heterochromatin to transition to the open, activated euchromatin state necessary for transcription. A third, less studied epigenetic pathway involves the reading of these specific histone marks once placed. The BETs (bromodomain and extraterminal-containing protein family), which includes BRD2, BRD3, and BRD4 and the testis-restricted BRDT, are epigenetic reader proteins that bind to specific acetylated lysine residues on histone tails where they facilitate the assembly of transcription complexes including transcription factors and transcriptional machinery like RNA Polymerase II. As reviewed here, considerable recent data establishes BETs as novel determinants of induced transcriptional programs in vascular cells, like endothelial cells and vascular smooth muscle cells, cardiac myocytes and inflammatory cells, like monocyte/macrophages, cellular settings where these epigenetic reader proteins couple proximal stimuli to chromatin, acting at super-enhancer regulatory regions to direct gene expression. BET inhibition, including the use of specific chemical BET inhibitors like JQ-1, has many reported effects in vivo in the cardiovascular setting, like decreasing atherosclerosis, angiogenesis, intimal hyperplasia, pulmonary arterial hypertension, and cardiac hypertrophy. At the same time, data in endothelial cells, adipocytes, and elsewhere suggest BETs also help regulate gene expression under basal conditions. Studies in the cardiovascular setting have highlighted BET action as a means of controlling gene expression in differentiation, cell identity, and cell state transitions, whether physiological or pathological, adaptive, or maladaptive. While distinct BET inhibitors are being pursued as therapies in oncology, a large prospective clinical cardiovascular outcome study investigating the BET inhibitor RVX-208 (now called apabetalone) has already been completed. Independent of this specific agent and this one trial or the numerous unanswered questions that remain, BETs have emerged as novel epigenetic players involved in the execution of coordinated transcriptional programs in cardiovascular health and disease.


Assuntos
Doenças Cardiovasculares/genética , Montagem e Desmontagem da Cromatina , Epigênese Genética , Histonas/metabolismo , Fatores de Transcrição/genética , Transcrição Gênica , Acetilação , Animais , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/metabolismo , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Humanos , Quinazolinonas/uso terapêutico , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Transcrição Gênica/efeitos dos fármacos
9.
Curr Microbiol ; 79(8): 229, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35767080

RESUMO

Chinese cordyceps is a well-known fungus-larva complex with medicinal and economic importance. At present the occurrence of Chinese cordyceps has not been fully illuminated. In this study, the microbial diversities of fertilized Thitarodes eggs from sites A (high occurrence rates of Chinese cordyceps), B (low occurrence rates), and C (no Chinese cordyceps) were analyzed using 16S rRNA and ITS gene-sequencing technique. The previous sequencing data of soil from the same sites were conjointly analyzed. The results showed that bacterial communities among the eggs were significantly different. The bacterial diversity and evenness were much higher on site A. Wolbachia was overwhelmingly predominant in the eggs of sites B and C, while Spiroplasma showed preference on site A. The fungal between-group differences in the eggs were not as significant as that of bacteria. Purpureocillium in Cordyceps-related families showed preference on site A. Wolbachia, Spiroplasma, and Purpureocillium were inferred to be closely related to Chinese cordyceps occurrence. Intra-kingdom and inter-kingdom network analyses suggest that closer correlations of microbial communities (especially closer fungal positive correlations) in fertilized eggs might promote Chinese cordyceps occurrence. Besides, metabolic pathway analysis showed that in fertilized eggs or soil the number of bacterial metabolic pathways with significant differences in every comparison between two sites was greater than that of fungi. Collectively, this study provides novel information about the occurrence of Chinese cordyceps, contributing to the large-scale artificial cultivation of Chinese cordyceps.


Assuntos
Cordyceps , Hypocreales , Mariposas , Animais , Bactérias/genética , Cordyceps/genética , Humanos , Hypocreales/genética , RNA Ribossômico 16S/genética , Solo , Zigoto
10.
Int J Mol Sci ; 23(18)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36142759

RESUMO

Obesity is increasing at epidemic rates across the US and worldwide, as are its co-morbidities, including type-2 diabetes and cardiovascular disease. Thus, targeted interventions to reduce the prevalence of obesity are of the utmost importance. The sigma-1 receptor (S1R) and sigma-2 receptor (S2R; encoded by Tmem97) belong to the same class of drug-binding sites, yet they are genetically distinct. There are multiple ongoing clinical trials focused on sigma receptors, targeting diseases ranging from Alzheimer's disease through chronic pain to COVID-19. However, little is known regarding their gene-specific role in obesity. In this study, we measured body composition, used a comprehensive laboratory-animal monitoring system, and determined the glucose and insulin tolerance in mice fed a high-fat diet. Compared to Sigmar1+/+ mice of the same sex, the male and female Sigmar1-/- mice had lower fat mass (17% and 12% lower, respectively), and elevated lean mass (16% and 10% higher, respectively), but S1R ablation had no effect on their metabolism. The male Tmem97-/- mice exhibited 7% lower fat mass, 8% higher lean mass, increased volumes of O2 and CO2, a decreased respiratory exchange ratio indicating elevated fatty-acid oxidation, and improved insulin tolerance, compared to the male Tmem97+/+ mice. There were no changes in any of these parameters in the female Tmem97-/- mice. Together, these data indicate that the S1R ablation in male and female mice or the S2R ablation in male mice protects against diet-induced adiposity, and that S2R ablation, but not S1R deletion, improves insulin tolerance and enhances fatty-acid oxidation in male mice. Further mechanistic investigations may lead to translational strategies to target differential S1R/S2R regulations and sexual dimorphism for precision treatments of obesity.


Assuntos
COVID-19 , Insulinas , Receptores sigma/metabolismo , Adiposidade , Animais , Dióxido de Carbono/farmacologia , Dieta Hiperlipídica , Feminino , Glucose/farmacologia , Insulinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/genética , Receptores sigma/genética , Caracteres Sexuais , Receptor Sigma-1
11.
Angew Chem Int Ed Engl ; 61(3): e202115384, 2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-34784090

RESUMO

Paspaline-derived indole diterpenes (IDTs) are structurally complex mycotoxins with unique tremorgenic activity. Reported are asymmetric total syntheses of three paspaline-derived IDTs paspalicine, paspalinine and paspalinine-13-ene. Our synthesis features a green Achmatowicz rearrangement/bicycloketalization for the efficient construction of FG rings (75 % yield) and a cascade ring-closing metathesis of dienyne for highly regioselective formation of CD rings (72 % yield). Other highlights include four palladium-mediated reactions (Stille, aza-Wacker, Suzuki, and Heck) to forge the BE rings and the installation of two continuous all-carbon quaternary stereocenters via reductive ring-opening of cyclopropane and α-methylation of the conjugate ester. Our new synthetic strategy is expected to be applicable to the chemical synthesis of other paspaline-derived IDTs and will facilitate the bioactivity studies of these agriculturally and pharmacologically important IDTs.

12.
Rheumatology (Oxford) ; 60(11): 5089-5097, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33693494

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of SHR4640, a highly selective urate transporter 1 inhibitor, in Chinese subjects with hyperuricaemia. METHODS: This was a randomized double-blind dose-ranging phase II study. Subjects whose serum uric acid (sUA) levels were ≥480 µmol/l with gout, ≥480 µmol/l without gout but with comorbidities, or ≥540 µmol/l were enrolled. Subjects were randomly assigned (1:1:1:1:1) to receive once daily 2.5 mg, 5 mg, 10 mg of SHR4640, 50 mg of benzbromarone or placebo, respectively. The primary end point was the proportion of subjects who achieved target sUA level of ≤360 µmol/l at week 5. RESULTS: 99.5% of subjects (n = 197) were male and 95.9% of subjects had gout history. The proportions of subjects who achieved target sUA at week 5 were 32.5%, 72.5% and 61.5% in the 5 mg, 10 mg SHR4640 and benzbromarone groups, respectively, significantly higher than the placebo group (0%; P < 0.05 for 5 mg and 10 mg SHR4640 group). The sUA was reduced by 32.7%, 46.8% and 41.8% at week 5 with 5 mg, 10 mg SHR4640 and benzbromarone, respectively, vs placebo (5.9%; P < 0.001 for each comparison). The incidences of gout flares requiring intervention were similar among all groups. Occurrences of treatment-emergent adverse events (TEAEs) were comparable across all groups, and serious TEAEs were not reported. CONCLUSIONS: The present study indicated a superior sUA-lowering effect and well tolerated safety profile after 5-week treatment with once-daily 5 mg/10 mg of SHR4640 as compared with placebo in Chinese subjects with hyperuricaemia. TRIAL REGISTRATION: ClinicalTrials.gov number, NCT03185793.


Assuntos
Ciclobutanos/uso terapêutico , Hiperuricemia/tratamento farmacológico , Transportadores de Ânions Orgânicos/antagonistas & inibidores , Proteínas de Transporte de Cátions Orgânicos/antagonistas & inibidores , Quinolinas/uso terapêutico , Adolescente , Adulto , Idoso , Ciclobutanos/farmacologia , Método Duplo-Cego , Feminino , Humanos , Nefropatias/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Quinolinas/farmacologia , Resultado do Tratamento , Adulto Jovem
13.
Acc Chem Res ; 53(11): 2726-2737, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33074659

RESUMO

Native to the Asia-Pacific region and widely applied in traditional Chinese medicine, the genus Daphniphyllum has produced over 330 known Daphniphyllum alkaloids. Investigations into these alkaloids have shown an exceptional range of interesting bioactivities. Challenging and caged polycyclic architectures and the promising biological profiles make Daphniphyllum alkaloids intriguing synthetic targets. Based on their backbones, these alkaloids can be categorized into 13-35 structurally distinct subfamilies. In addition to our work, almost 30 impressive total syntheses of Daphniphyllum alkaloids from seven subfamilies, namely, daphniphylline-type, secodaphniphylline-type, daphnilactone A-type, bukittinggine-type, daphmanidin A-type, calyciphylline A-type, and calyciphylline B-type alkaloids, have been reported by 11 research groups. However, many Daphniphyllum alkaloid subfamilies remain inaccessible by chemical synthesis.In this Account, we summarize our recent endeavors in the total synthesis of Daphniphyllum alkaloids commencing from simple chiral bicyclic synthons. Daphniphyllum alkaloids with diversified skeletons from four different subfamilies, namely, calyciphylline A-type, daphnezomine A-type, bukittinggine-type, and yuzurimine-type alkaloids, have been achieved. Furthermore, the tricyclic core structure of daphniglaucin C-type alkaloids daphnimacropodines was also synthesized. First, we describe a 14-step synthesis of calyciphylline A-type alkaloid (-)-himalensine A, which features a mild Cu-mediated nitrile hydration, an intramolecular Heck reaction to assemble the pivotal 2-azabicyclo[3.3.1]nonane moiety, and a Meinwald rearrangement to introduce the critical oxidative state into the skeleton. We then introduce the synthesis of daphnezomine A-type alkaloid dapholdhamine B, which possesses a unique aza-adamantane core. This target molecule was fabricated using key reactions including Huang's amide-activation-annulation. An unexpected radical detosylation during the synthesis of dapholdhamine B further inspired an ambitious radical cyclization cascade strategy, which eventually led to an efficient total synthesis of bukittinggine-type alkaloid (-)-caldaphnidine O. This highly chemo-, regio-, and stereoselective radical reaction cascade also shed light on the synthetic strategy of other alkaloids with caged structures. We next describe the first total synthesis of yuzurimine-type alkaloid (+)-caldaphnidine J. The key steps in our approach include a Pd-catalyzed regioselective hydroformylation and a novel Swern oxidation/ketene dithioacetal Prins reaction cascade. The work has achieved the first synthesis of a member of the largest subfamily of Daphniphyllum alkaloids. Finally, we show our efforts toward the total synthesis of daphniglaucin C-type alkaloids. Overall, we hope that the interesting strategies and synthetic methods demonstrated in our efforts could inspire a wide variety of additional applications to natural product synthesis.


Assuntos
Alcaloides/síntese química , Compostos Bicíclicos com Pontes/química , Daphniphyllum/química , Alcaloides/química , Ciclização , Daphniphyllum/metabolismo , Cetonas/química , Estereoisomerismo
14.
Reproduction ; 162(6): 437-448, 2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34605773

RESUMO

The number of children born after assisted reproductive technology (ART) is accumulating rapidly, and the health problems of the children are extensively concerned. This study aims to evaluate whether ART procedures alter behaviours in male offspring. Mouse models were utilized to establish three groups of offspring conceived by natural conception (NC), in vitro fertilization and embryo transfer (IVF-ET), and frozen-thawed embryo transfer (IVF-FET), respectively. A battery of behaviour experiments for evaluating anxiety and depression levels, including the open field test (OFT), elevated plus maze (EPM) test, light/dark transition test (L/DTT), tail suspension test (TST), forced swimming test (FST), and sucrose preference test (SPT) was carried out. Aged (18 months old), but not young (3 months old), male offspring in the IVF-ET and IVF-FET groups, compared with those in the NC group, exhibited increased anxiety and depression-like behaviours. The protein expression levels of three neurotrophins in PFC or hippocampus in aged male offspring from the IVF-ET and IVF-FET groups reduced at different extent, in comparison to NC group. RNA sequencing (RNA-Seq) was performed in the hippocampus of 18 months old offspring to further explore the gene expression profile changes in the three groups. KEGG analyses revealed the coexisted pathways, such as PI3K-Akt signalling pathway, which potentially reflected the similarity and divergence in anxiety and depression between the offspring conceived by IVF-ET and IVF-FET. Our research suggested the adverse effects of advanced age on the psychological health of children born after ART should be highlighted in the future.


Assuntos
Depressão , Fosfatidilinositol 3-Quinases , Animais , Ansiedade/etiologia , Depressão/etiologia , Fertilização in vitro/efeitos adversos , Masculino , Camundongos , Técnicas de Reprodução Assistida/efeitos adversos , Estudos Retrospectivos
15.
Br J Clin Pharmacol ; 87(3): 1475-1485, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32959915

RESUMO

AIMS: To determine the absorption, distribution, metabolism and excretion of abivertinib, a third-generation epidermal growth factor receptor tyrosine kinase inhibitor, in patients with advanced non-small cell lung cancer (NSCLC). METHODS: Seven patients with advanced NSCLC were given a single 200 mg/83 µCi oral suspension of [14 C]-abivertinib. Blood, urine and faeces were collected. Mass balance of radioactivity, the pharmacokinetics of abivertinib, and the total radioactivity were determined. Metabolite profiling and characterisation were performed. RESULTS: The mean recovery was 82.16%, with 2.38 and 79.78% of the radioactive dose excreted in urine and faeces, respectively. The unchanged abivertinib was the major radioactive component detected in plasma within the first 24 hours after dosing, accounting for 59.17% of the total drug-related radioactivity. Abivertinib in urine accounted for only 0.96% of the administered dose, whereas in faeces it accounted for 33.36%. Eight metabolites were detected and characterised in plasma, among which MII-7, a product of cysteine glycine conjugate, was the only circulating metabolite, accounting for approximate 10.6% of the total drug-related exposure. MII-2 (an abivertinib cysteine-glycine adduct) and M7 (a reduced product of abivertinib) were the 2 major metabolites in the excreta, accounting for 20.0 and 12.4%, respectively, of the drug-related radioactivity in faeces. CONCLUSION: Following a single oral administration, the unchanged abivertinib was the predominant drug-related material in plasma, urine and faeces. The drug-related materials were primarily eliminated via the faecal route. Direct glutathione conjugation of abivertinib played a significant role in the metabolic clearance and metabolite exposure of abivertinib.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Administração Oral , Radioisótopos de Carbono , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Receptores ErbB , Fezes , Glutationa , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas
16.
J Surg Res ; 257: 294-305, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32871430

RESUMO

BACKGROUND: Drug-eluting stents impair post-angioplasty re-endothelialization thus compromising restenosis prevention while heightening thrombotic risks. We recently found that inhibition of protein kinase RNA-like endoplasmic reticulum kinase (PERK) effectively mitigated both restenosis and thrombosis in rodent models. This motivated us to determine how PERK inhibition impacts re-endothelialization. METHODS: Re-endothelialization was evaluated in endothelial-denuded rat carotid arteries after balloon angioplasty and periadventitial administration of PERK inhibitor in a hydrogel. To study whether PERK in smooth muscle cells (SMCs) regulates re-endothelialization by paracrinally influencing endothelial cells (ECs), denuded arteries exposing SMCs were lentiviral-infected to silence PERK; in vitro, the extracellular vesicles isolated from the medium of PDGF-activated, PERK-upregulating human primary SMCs were transferred to human primary ECs. RESULTS: Treatment with PERK inhibitor versus vehicle control accelerated re-endothelialization in denuded arteries. PERK-specific silencing in the denuded arterial wall (mainly SMCs) also enhanced re-endothelialization compared to scrambled shRNA control. In vitro, while medium transfer from PDGF-activated SMCs impaired EC viability and increased the mRNA levels of dysfunctional EC markers, either PERK inhibition or silencing in donor SMCs mitigated these EC changes. Furthermore, CXCL10, a paracrine cytokine detrimental to ECs, was increased by PDGF activation and decreased after PERK inhibition or silencing in SMCs. CONCLUSIONS: Attenuating PERK activity pharmacologically or genetically provides an approach to accelerating post-angioplasty re-endothelialization in rats. The mechanism may involve paracrine factors regulated by PERK in SMCs that impact neighboring ECs. This study rationalizes future development of PERK-targeted endothelium-friendly vascular interventions.


Assuntos
Angioplastia com Balão/efeitos adversos , Reestenose Coronária/prevenção & controle , Miócitos de Músculo Liso/efeitos dos fármacos , Inibidores de Proteínas Quinases/administração & dosagem , Reepitelização/efeitos dos fármacos , eIF-2 Quinase/antagonistas & inibidores , Angioplastia com Balão/instrumentação , Animais , Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/patologia , Artérias Carótidas/cirurgia , Reestenose Coronária/etiologia , Modelos Animais de Doenças , Stents Farmacológicos/efeitos adversos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Humanos , Masculino , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Comunicação Parácrina/efeitos dos fármacos , Comunicação Parácrina/genética , RNA Interferente Pequeno/metabolismo , Ratos , Reepitelização/genética , eIF-2 Quinase/genética
17.
Fish Shellfish Immunol ; 117: 104-112, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34333126

RESUMO

Cell survival is based on the stability of intracellular state. It was well known that biochemical reactions in cells require specific intracellular environments, such as pH and calcium concentration. While the mechanism of stabilizing the intracellular environment is complex and far from clear. In this study, a Sma and Mad related protein 5 gene (LvSmad5) of Litopenaeus vannamei was cloned. LvSmad5 was located to both cytoplasm and nucleus. And subcellular localization of LvSmad5 was responsed to the changing of cells internal and external environment. Besides, it was found that subcellular localization of LvSmad5 was also regulated by unfolded protein response. Moreover, it was proved that nucleic localization of LvSmad5 could significantly increase the white spot syndrome virus (WSSV) infection in shrimp, and knockdown expression of LvSmad5 decreased the cumulative mortality of WSSV infection shrimp. Further investigation revealed that cytoplasm LvSmad5 could interplay with shrimp hexokinase 1, and contribute to glycolysis. These results indicated that LvSmad5 played a role in L. vannamei environmental stress response, and was used by WSSV for its replication.


Assuntos
Infecções por Vírus de DNA/genética , Doenças dos Peixes/genética , Proteínas de Peixes/genética , Penaeidae/genética , Proteína Smad5/genética , Estresse Fisiológico/genética , Vírus da Síndrome da Mancha Branca 1/fisiologia , Sequência de Aminoácidos , Animais , Núcleo Celular , Clonagem Molecular , Citoplasma , Infecções por Vírus de DNA/mortalidade , Infecções por Vírus de DNA/veterinária , Infecções por Vírus de DNA/virologia , Doenças dos Peixes/mortalidade , Doenças dos Peixes/virologia , Penaeidae/virologia , Resposta a Proteínas não Dobradas/genética , Replicação Viral
18.
J Fish Biol ; 99(4): 1236-1246, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34101179

RESUMO

Growth rate and energy reserves are important determinants of fitness and are governed by endogenous and exogenous factors. Thus, examining the influence of individual and multiple stressors on growth and energy reserves can help estimate population health under current and future conditions. In young anadromous fishes, freshwater habitat quality determines physiological state and fitness of juveniles emigrating to marine habitats. In this study, the authors tested how temperature and food availability affect survival, growth and energy reserves in juvenile anadromous alewives (Alosa pseudoharengus), a forage fish distributed along the eastern North American continent. Field-collected juvenile anadromous A. pseudoharengus were exposed for 21 days to one of two temperatures (21°C and 25°C) and one of two levels of food rations (1% or 2% tank biomass daily) and compared for differences in final size, fat mass-at-length, lean mass-at-length and energy density. Increased temperature and reduced ration both led to lower growth rates, and the effect of reduced ration was greater at higher temperature. Fat mass-at-length decreased with dry mass, and energy density increased with total length, suggesting size-based endogenous influences on energy reserves. Lower ration also directly decreased fat mass-at-length, lean mass-at-length and energy density. Given the fitness implications of size and energy reserves, temperature and food availability should be considered important indicators of nursery habitat quality and incorporated in A. pseudoharengus life-history models to improve forecasting of population health under climate change.


Assuntos
Ecossistema , Peixes , Animais , Água Doce , Temperatura
19.
Br J Haematol ; 189(3): 428-437, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32297671

RESUMO

We explored the relationships between lymphocyte subsets, cytokines, pulmonary inflammation index (PII) and disease evolution in patients with (corona virus disease 2019) COVID-19. A total of 123 patients with COVID-19 were divided into mild and severe groups. Lymphocyte subsets and cytokines were detected on the first day of hospital admission and lung computed tomography results were quantified by PII. Difference analysis and correlation analysis were performed on the two groups. A total of 102 mild and 21 severe patients were included in the analysis. There were significant differences in cluster of differentiation 4 (CD4+ T), cluster of differentiation 8 (CD8+ T), interleukin 6 (IL-6), interleukin 10 (IL-10) and PII between the two groups. There were significant positive correlations between CD4+ T and CD8+ T, IL-6 and IL-10 in the mild group (r2  = 0·694, r 2  = 0·633, respectively; P < 0·01). After 'five-in-one' treatment, all patients were discharged with the exception of the four who died. Higher survival rates occurred in the mild group and in those with IL-6 within normal values. CD4+ T, CD8+ T, IL-6, IL-10 and PII can be used as indicators of disease evolution, and the PII can be used as an independent indicator for disease progression of COVID-19.


Assuntos
Betacoronavirus , Infecções por Coronavirus/imunologia , Citocinas/sangue , Pulmão/imunologia , Subpopulações de Linfócitos , Pneumonia Viral/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19 , Teste para COVID-19 , Técnicas de Laboratório Clínico , Infecções por Coronavirus/sangue , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/diagnóstico por imagem , Infecções por Coronavirus/fisiopatologia , Citocinas/imunologia , Progressão da Doença , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia/diagnóstico por imagem , Pneumonia Viral/sangue , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/fisiopatologia , SARS-CoV-2
20.
Artigo em Inglês | MEDLINE | ID: mdl-32081430

RESUMO

Polycystic ovary syndrome (PCOS) is a complicated reproductive endocrine disease characterized by hyperandrogenism, polycystic ovaries, and anovulation. Previous studies have revealed that androgen receptors (ARs) are strongly associated with hyperandrogenism and abnormalities in folliculogenesis in patients with PCOS. However, the kinases responsible for androgen receptor activity, especially in granulosa cells, and the role of casein kinase 2α (CK2α) specifically in the pathogenesis of PCOS, remain unknown. Here, we show that both CK2α protein and mRNA levels were higher in luteinized granulosa cells of patients with PCOS compared with non-PCOS, as well as in the ovarian tissues of mice with a dehydroepiandrosterone-induced PCOS-like phenotype, compared with controls. In addition, CK2α not only interacted with AR in vivo and in vitro, but it also phosphorylated and stabilized AR, triggering AR and ovulation related genes excessive expression. CK2α also promoted cell proliferation in the KGN cell line and inhibited apoptosis. Collectively, the finding highlighted that the CK2α-AR axis probably caused the etiology of the PCOS. Thus, CK2α might be a promising clinical therapeutic target for PCOS treatment.

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