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1.
Mol Biol Evol ; 38(2): 486-501, 2021 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-32946576

RESUMO

Bumblebees are a diverse group of globally important pollinators in natural ecosystems and for agricultural food production. With both eusocial and solitary life-cycle phases, and some social parasite species, they are especially interesting models to understand social evolution, behavior, and ecology. Reports of many species in decline point to pathogen transmission, habitat loss, pesticide usage, and global climate change, as interconnected causes. These threats to bumblebee diversity make our reliance on a handful of well-studied species for agricultural pollination particularly precarious. To broadly sample bumblebee genomic and phenotypic diversity, we de novo sequenced and assembled the genomes of 17 species, representing all 15 subgenera, producing the first genus-wide quantification of genetic and genomic variation potentially underlying key ecological and behavioral traits. The species phylogeny resolves subgenera relationships, whereas incomplete lineage sorting likely drives high levels of gene tree discordance. Five chromosome-level assemblies show a stable 18-chromosome karyotype, with major rearrangements creating 25 chromosomes in social parasites. Differential transposable element activity drives changes in genome sizes, with putative domestications of repetitive sequences influencing gene coding and regulatory potential. Dynamically evolving gene families and signatures of positive selection point to genus-wide variation in processes linked to foraging, diet and metabolism, immunity and detoxification, as well as adaptations for life at high altitudes. Our study reveals how bumblebee genes and genomes have evolved across the Bombus phylogeny and identifies variations potentially linked to key ecological and behavioral traits of these important pollinators.


Assuntos
Adaptação Biológica/genética , Abelhas/genética , Evolução Biológica , Genoma de Inseto , Animais , Uso do Códon , Elementos de DNA Transponíveis , Dieta , Comportamento Alimentar , Componentes do Gene , Tamanho do Genoma , Seleção Genética
2.
Anal Chem ; 91(9): 5638-5645, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30968686

RESUMO

Rational design of practical probes with excellent specificity and improved optical properties for a particular enzyme is always a big challenge. Herein, a practical and highly specific fluorescent probe for carboxylesterase 1 (CES1) was rationally designed using meso-carboxyl-BODIPY as the basic fluorophore based on the substrate preference and catalytic properties of CES1. Following molecular docking-based virtual screening combined with reaction phenotyping-based experimental screening, we found that MMB (probe 7) exhibited the optimal combination of sensitivity and specificity toward human CES1 in contrast to other ester derivatives. Under physiological conditions, MMB could be readily hydrolyzed by CES1 and release MCB; such biotransformation brought great changes in the electronic properties at the meso position of the fluorophore and triggered a dramatic increase in fluorescence emission around 595 nm. Moreover, MMB was cell membrane permeable and was successfully applied to monitor the real activities of CES1 in various biological samples including living cells, tissue slices, organs, and zebrafish. In summary, this study showed a good example for constructing specific fluorescent probe(s) for a target enzyme and also provided a practical and sensitive tool for real-time sensing of CES1 activities in complicated biological samples. All these findings would strongly facilitate high-throughput screening of CES1 modulators and the studies on CES1-associated physiological and pathological processes.


Assuntos
Carboxilesterase/metabolismo , Desenho de Fármacos , Corantes Fluorescentes/química , Animais , Compostos de Boro/química , Células CACO-2 , Carboxilesterase/química , Humanos , Hidrólise , Modelos Moleculares , Imagem Molecular , Conformação Proteica , Peixe-Zebra
3.
Bioorg Chem ; 80: 577-584, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30032067

RESUMO

Pancreatic lipase (PL), a key enzyme responsible for the hydrolysis of triacylglycerides in the gastrointestinal tract, has been identified as the therapeutic target for the regulation of lipid absorption. In the present study, six major constituents from a famous Chinese herbal medicine Cortex Mori Radicis (also named sangbaipi in Chinese), have been collected and their inhibitory effects on PL have been carefully investigated and well characterized by a fluorescence-based assay. The results clearly demonstrated that all tested bioactive constituents from Cortex Mori Radicis including sanggenone C (SC), sanggenone D (SD), kuwanon C (KC), kuwanon G (KG), morin and morusin displayed strong to moderate inhibitory effects towards PL with the IC50 values ranging from 0.77 µM to 20.56 µM. Further investigations on inhibition kinetics demonstrated that SC, SD, KC and KG functioned as potent and mixed inhibitors against PL-mediated 4-MU oleate hydrolysis, with the Ki values less than 5.0 µM. Furthermore, molecular docking simulations demonstrated that SD (the most potent PL inhibitor from Cortex Mori Radicis) could create strong interaction with Ser152 (the key amino acid in the catalytic triad) of PL via hydrogen bonding. All these findings provided a new powerful evidence for explaining the hypolipidemic effect of Cortex Mori Radicis, also suggested that some abundant natural compounds in this herbal medicine could be served as lead compounds for the development of new PL inhibitors.


Assuntos
Derivados de Benzeno/farmacologia , Benzofuranos/farmacologia , Cromonas/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Lipase/antagonistas & inibidores , Animais , Derivados de Benzeno/química , Benzofuranos/química , Cromonas/química , Medicamentos de Ervas Chinesas/química , Inibidores Enzimáticos/química , Flavonoides/química , Lipase/metabolismo , Simulação de Acoplamento Molecular , Morus/química , Pâncreas/enzimologia , Suínos
5.
Yao Xue Xue Bao ; 52(1): 58-65, 2017 01.
Artigo em Zh | MEDLINE | ID: mdl-29911769

RESUMO

Carboxylesterase 1 (CE1) is an important serine hydrolase in mammals, which involved in the hydrolysis of a variety of compounds (endogenous substrates like cholesterol and xenobiotic compounds like ester-contain drugs and pesticides). This study aimed to design and develop the fluorescent probe substrates for human carboxylesterase 1 (hCE1), on the basis of the structural features of hCE1 preferred substrates. Four carboxylic esters deriving from BODIPY-8-carboxylic acid were designed and synthesized. After then, reaction phenotyping assays and chemical inhibition assays were used to evaluate the selectivity of these four ester derivatives towards hCE1. Our results clearly demonstrated that the substrate specificity of these ester substrates towards hCE1 would be improved with the decrease of the alcohol group on BODIPY-8-carboxylesters, while BODIPY-8-carboxylesters with small alcohol groups including methyl (BCM) and ethyl (BCE) esters could serve as the ideal probe substrates for hCE1. Given that BCM exhibit rapid hydrolytic rate in hCE1, we further investigate the enzymatic kinetics of this fluorescent probe substrate in both human liver microsomes (HLM) and recombinant hCE1, as well as to explore its potential application in high-throughput screening of hCE1 inhibitors by using HLM as enzyme source. The results showed that the kinetic behaviors and the affinity of BCM in HLM is much closed to those in recombinant hCE1, implying that hCE1 played the key roles in BCM hydrolysis in HLM. Furthermore, the inhibition study demonstrated that BCM could be used for rapid screening and characterization of hCE1 inhibitors, by using HLM to replace recombinant hCE1 as enzyme source.


Assuntos
Compostos de Boro/química , Hidrolases de Éster Carboxílico/química , Corantes Fluorescentes , Ésteres , Humanos , Hidrólise , Cinética , Microssomos Hepáticos/enzimologia , Especificidade por Substrato
6.
Redox Biol ; 76: 103323, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39180983

RESUMO

Targeting senescence has emerged as a promising strategy for liver cancer treatment. However, the lack of a safe agent capable of inducing complete senescence and being combined with senolytics poses a limitation. Here, we screened a natural product library and identified tryptanthrin (TRYP) as a potent inducer of cellular senescence in liver cancer cells both in vitro and in vivo. Mechanistically, Glutathione S-transferase P1 (GSTP1), a key regulator for redox homeostasis, was identified as a target protein for TRYP-induced senescence. TRYP directly bound to GSTP1 and inhibited its enzymatic activity, mediating reactive oxygen species (ROS) accumulation, followed by DNA damage response (DDR), consequently contributing to initiating primary senescence. Furthermore, TRYP triggered DNA damage-dependent activation of NF-κB pathway, which evoked senescence-associated secretory phenotype (SASP), thereby leading to senescence reinforcement. Importantly, TRYP exposed the vulnerability of tumor cells and sensitized senescent cells to apoptosis induced by senolytic agent ABT263, a Bcl2 inhibitor. Taken together, our findings reveal that TRYP induces cellular senescence via GSTP1/ROS/DDR/NF-κB/SASP axis, providing a novel potential application in synergizing with senolytic therapy in liver cancer.


Assuntos
Apoptose , Senescência Celular , Glutationa S-Transferase pi , Neoplasias Hepáticas , Quinazolinas , Espécies Reativas de Oxigênio , Humanos , Senescência Celular/efeitos dos fármacos , Glutationa S-Transferase pi/metabolismo , Glutationa S-Transferase pi/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Apoptose/efeitos dos fármacos , Quinazolinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Camundongos , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Senoterapia/farmacologia , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Compostos de Anilina/farmacologia , Fenótipo Secretor Associado à Senescência/efeitos dos fármacos , Sulfonamidas/farmacologia
7.
Acta Pharm Sin B ; 14(2): 729-750, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38322326

RESUMO

Chemotherapy-induced complications, particularly lethal cardiovascular diseases, pose significant challenges for cancer survivors. The intertwined adverse effects, brought by cancer and its complication, further complicate anticancer therapy and lead to diminished clinical outcomes. Simple supplementation of cardioprotective agents falls short in addressing these challenges. Developing bi-functional co-therapy agents provided another potential solution to consolidate the chemotherapy and reduce cardiac events simultaneously. Drug repurposing was naturally endowed with co-therapeutic potential of two indications, implying a unique chance in the development of bi-functional agents. Herein, we further proposed a novel "trilogy of drug repurposing" strategy that comprises function-based, target-focused, and scaffold-driven repurposing approaches, aiming to systematically elucidate the advantages of repurposed drugs in rationally developing bi-functional agent. Through function-based repurposing, a cardioprotective agent, carvedilol (CAR), was identified as a potential neddylation inhibitor to suppress lung cancer growth. Employing target-focused SAR studies and scaffold-driven drug design, we synthesized 44 CAR derivatives to achieve a balance between anticancer and cardioprotection. Remarkably, optimal derivative 43 displayed promising bi-functional effects, especially in various self-established heart failure mice models with and without tumor-bearing. Collectively, the present study validated the practicability of the "trilogy of drug repurposing" strategy in the development of bi-functional co-therapy agents.

8.
Int J Comput Assist Radiol Surg ; 17(6): 981-991, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35286586

RESUMO

PURPOSE: Facial repair surgeries (FRS) require accuracy for navigating the critical anatomy safely and quickly. The purpose of this paper is to develop a method to directly track the position of the patient using video data acquired from the single camera, which can achieve noninvasive, real time, and high positioning accuracy in FRS. METHODS: Our method first performs camera calibration and registers the surface segmented from computed tomography to the patient. Then, a two-step constraint algorithm, which includes the feature local constraint and the distance standard deviation constraint, is used to find the optimal feature matching pair quickly. Finally, the movements of the camera and the patient decomposed from the image motion matrix are used to track the camera and the patient, respectively. RESULTS: The proposed method achieved fusion error RMS of 1.44 ± 0.35, 1.50 ± 0.15, 1.63 ± 0.03 mm in skull phantom, cadaver mandible, and human experiments, respectively. The above errors of the proposed method were lower than those of the optical tracking system-based method. Additionally, the proposed method could process video streams up to 24 frames per second, which can meet the real-time requirements of FRS. CONCLUSIONS: The proposed method does not rely on tracking markers attached to the patient; it could be executed automatically to maintain the correct augmented reality scene and overcome the decrease in positioning accuracy caused by patient movement during surgery.


Assuntos
Realidade Aumentada , Cirurgia Assistida por Computador , Algoritmos , Humanos , Imageamento Tridimensional/métodos , Imagens de Fantasmas , Cirurgia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos
9.
Insects ; 12(11)2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-34821764

RESUMO

In eukaryotes, DNA of mitochondria is transferred into the nucleus and forms nuclear mitochondrial DNAs (NUMTs). Taking advantage of the abundant genomic resources for bumblebees, in this study, we de novo generated mitochondrial genomes (mitogenomes) for 11 bumblebee species. Then, we identified and characterized NUMTs in genus-wide bumblebee species. The number of identified NUMTs varies across those species, with numbers ranging from 32 to 72, and nuclear genome size is not positively related to NUMT number. The insertion sites of NUMTs in the nuclear genome are not random, with AT-rich regions harboring more NUMTs. In addition, our results suggest that NUMTs derived from the mitochondrial COX1 gene are most abundant in the bumblebee nuclear genome. Although the majority of NUMTs are found within intergenic regions, some NUMTs do reside within genic regions. Transcripts that contain both the NUMT sequence and its flanking non-NUMT sequences could be found in the bumblebee transcriptome, suggesting a potential domestication of NUMTs in the bumblebee. Taken together, our results shed light on the molecular features of NUMTs in the bumblebee and uncover their contribution to genome innovation.

10.
Int J Med Robot ; 17(5): e2300, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34109730

RESUMO

BACKGROUND: Robotic-assisted total knee arthroplasty (TKA) was performed to promote the accuracy of bone resection and mechanical alignment. Among these TKA system procedures, 3D reconstruction of CT data of lower limbs consumes significant manpower. Artificial intelligence (AI) algorithms applying deep learning has been proved efficient in automated identification and visual processing. METHODS: CT data of a total of 200 lower limbs scanning were used for AI-based 3D model construction and CT data of 20 lower limbs scanning were utilised for verification. RESULTS: We showed that the performance of an AI-guided 3D reconstruction of CT data of lower limbs for robotic-assisted TKA was similar to that of the operator-based approach. The time of 3D lower limb model construction using AI was 4.7 min. AI-based 3D models can be used for surgical planning. CONCLUSION: AI was used for the first time to guide the 3D reconstruction of CT data of lower limbs for facilitating robotic-assisted TKA. Incorporation of AI in 3D model reconstruction before TKA might reduce the workload of radiologists.


Assuntos
Artroplastia do Joelho , Aprendizado Profundo , Prótese do Joelho , Procedimentos Cirúrgicos Robóticos , Inteligência Artificial , Humanos , Articulação do Joelho/cirurgia , Extremidade Inferior/diagnóstico por imagem , Extremidade Inferior/cirurgia , Tomografia Computadorizada por Raios X
11.
Int J Med Robot ; 17(4): e2264, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33855810

RESUMO

BACKGROUND: We investigated the accuracy and safety of a new HURWA robotic-assisted total knee arthroplasty (TKA) system in a sheep model. METHODS: Ten male small-tailed Han sheep were used in this study. Sheep were imaged by computed tomography scan before and after bone resection and the cutting errors between actual bone preparation and preoperative planning of the femur and tibia in three dimensions were measured. RESULTS: The overall accuracies after surgery compared with that from preoperative surgical planning of the left and right femurs were 1.93 ± 1.02° and 1.93 ± 1.23°, respectively. Additionally, similarly high overall accuracies for the left and right tibia of 1.26 ± 1.04 and 1.68 ± 0.92°, respectively, were obtained. The gap distances of the distal cut, anterior chamfer, anterior cut, posterior chamfer and posterior cut on the medial side were 0.47 ± 0.35 mm, 0.41 ± 0.37 mm, 0.12 ± 0.26 mm, 0.41 ± 0.44 mm and 0.12 ± 0.23 mm, respectively. No intraoperative complications, such as intraoperative fracture, massive bleeding or death, occurred. CONCLUSION: This new HURWA robotic-assisted TKA system is an accurate and safe tool for TKA surgery based on the sheep model.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Procedimentos Cirúrgicos Robóticos , Animais , Fêmur/cirurgia , Humanos , Articulação do Joelho/cirurgia , Masculino , Ovinos , Tíbia/diagnóstico por imagem , Tíbia/cirurgia
12.
Mitochondrial DNA B Resour ; 4(2): 2729-2730, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-33365703

RESUMO

Elsholtzia splendens is a copper-tolerance plant colonized in copper mines in southern China. In this study, we sequenced and de novo assembled the complete chloroplast genome of E. splendens. The complete chloroplast genome is 150,761 bp (37.8% of GC) in length and contains 87 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. Phylogenetic analysis revealed that among the 11 Lamiaceae species, Perilla citriodor is the closest relative of E. splendens. The complete chloroplast genome of E. splendens provides a valuable resource for comparative and evolutionary analysis among Lamiaceae species and may be helpful in understanding the molecular mechanism of copper tolerance in E. splendens.

13.
Chem Biol Interact ; 308: 339-349, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31170387

RESUMO

Magnolol, the most abundant bioactive constituent of the Chinese herb Magnolia officinalis, has been found with multiple biological activities, including anti-oxidative, anti-inflammatory and enzyme-regulatory activities. In this study, the inhibitory effects and inhibition mechanism of magnolol on human carboxylesterases (hCEs), the key enzymes responsible for the hydrolytic metabolism of a variety of endogenous esters as well as ester-bearing drugs, have been well-investigated. The results demonstrate that magnolol strongly inhibits hCE1-mediated hydrolysis of various substrates, whereas the inhibition of hCE2 by magnolol is substrate-dependent, ranging from strong to moderate. Inhibition of intracellular hCE1 and hCE2 by magnolol was also investigated in living HepG2 cells, and the results showed that magnolol could strongly inhibit intracellular hCE1, while the inhibition of intracellular hCE2 was weak. Inhibition kinetic analyses and docking simulations revealed that magnolol inhibited both hCE1 and hCE2 in a mixed manner, which could be partially attributed to its binding at two distinct ligand-binding sites in each carboxylesterase, including the catalytic cavity and the regulatory domain. In addition, the potential risk of the metabolic interactions of magnolol via hCE1 inhibition was predicted on the basis of a series of available pharmacokinetic data and the inhibition constants. All these findings are very helpful in deciphering the metabolic interactions between magnolol and hCEs, and also very useful for avoiding deleterious interactions via inhibition of hCEs.


Assuntos
Compostos de Bifenilo/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Lignanas/metabolismo , Sítios de Ligação , Biocatálise , Compostos de Bifenilo/química , Hidrolases de Éster Carboxílico/antagonistas & inibidores , Domínio Catalítico , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/metabolismo , Células Hep G2 , Humanos , Hidrólise , Cinética , Lignanas/química , Simulação de Acoplamento Molecular
14.
Int J Biol Macromol ; 118(Pt B): 2216-2223, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30009906

RESUMO

Reduction of lipid absorption has been recognized as an attractive approach for the discovery of new drugs to treat obesity and overweight. The leave extract of Ginkgo biloba has been widely used for the treatment of metabolic diseases (such as hyperlipidemia) in both eastern and western countries, but the bioactive compounds in Ginkgo biloba and the underlying mechanism have not been fully characterized. This study aimed to investigate the inhibition potentials and mechanism of major biflavones from G. biloba on pancreatic lipase (PL), a key target regulating lipid absorption. The results clearly demonstrated that all tested biflavones in G. biloba including isoginkgetin, bilobetin, ginkgetin and sciadopitysin, displayed strong to moderate inhibitory effects on PL with the IC50 values ranging from 2.90 µM to 12.78 µM. Further investigations on both inhibition kinetic analyses and docking simulations demonstrated that isoginkgetin, bilobetin and ginkgetin were potent PL inhibitors (Ki < 2.5 µM), which could create strong interactions with the catalytic triad of PL via hydrogen bonding. These findings provided a new powerful evidence for explaining the hypolipidemic effects of G. biloba, while these newly identified PL inhibitors from G. biloba could serve as lead compounds for the development of biflavonoid-type PL inhibitors.


Assuntos
Biflavonoides/farmacologia , Inibidores Enzimáticos/farmacologia , Ginkgo biloba/química , Lipase/antagonistas & inibidores , Pâncreas/enzimologia , Animais , Biflavonoides/química , Inibidores Enzimáticos/química , Concentração Inibidora 50 , Cinética , Lipase/metabolismo , Simulação de Acoplamento Molecular , Sus scrofa , Termodinâmica
15.
Int J Biol Macromol ; 120(Pt B): 1944-1954, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30268757

RESUMO

Human carboxylesterase 1 (hCE1) is a key enzyme responsible for the hydrolysis of a wide range of endogenous and xenobiotic esters, but the highly selective inhibitors against hCE1 are rarely reported. This study aimed to assess the inhibitory effects of natural flavonoids against hCE1 and to find potential specific hCE1 inhibitors. To this end, fifty-eight natural flavonoids were collected and their inhibitory effects against both hCE1 and hCE2 were assayed. Among all tested compounds, nevadensin, an abundant natural constitute from Lysionotus pauciflorus Maxim., displayed the best combination of inhibition potency and selectivity towards hCE1. The inhibition mechanism of nevadensin on hCE1 was further investigated using two site-specific hCE1 substrates including D-luciferin methyl ester (DME) and 2­(2­benzoyloxy­3­methoxyphenyl)benzothiazole (BMBT). Furthermore, docking simulations demonstrated that the binding area of nevadensin on hCE1 was highly overlapped with that of DME but was far away from that of BMBT, which was highly consistent with the inhibition modes of nevadensin. These findings found a natural occurring specific inhibitor of hCE1, which could be served as a lead compound for the development of novel hCE1 inhibitor with improved properties, and also hold great promise for investigating hCE1-ligand interactions.


Assuntos
Produtos Biológicos/farmacologia , Hidrolases de Éster Carboxílico/antagonistas & inibidores , Flavonas/farmacologia , Produtos Biológicos/metabolismo , Hidrolases de Éster Carboxílico/química , Hidrolases de Éster Carboxílico/metabolismo , Flavonas/metabolismo , Humanos , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Conformação Proteica , Especificidade por Substrato
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