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1.
Plant Cell Environ ; 47(4): 1185-1206, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38164066

RESUMO

Ethylene-responsive factors (ERFs) participate in a wide range of physiological and biological processes. However, many of the functions of ERFs in cold stress responses remain unclear. We, therefore, characterised the cold responses of RmERF54 in Rosa multiflora, a rose-related cold-tolerant species. Overexpression of RmERF54, which is a nuclear transcription factor, increases the cold resistance of transgenic tobacco and rose somatic embryos. In contrast, virus-induced gene silencing (VIGS) of RmERF54 increased cold susceptibility of R. multiflora. The overexpression of RmERF54 resulted in extensive transcriptional reprogramming of stress response and antioxidant enzyme systems. Of these, the levels of transcripts encoding the PODP7 peroxidase and the cold-related COR47 protein showed the largest increases in the somatic embryos with ectopic expression of RmERF54. RmERF54 binds to the promoters of the RmPODP7 and RmCOR47 genes and activates expression. RmERF54-overexpressing lines had higher antioxidant enzyme activities and considerably lower levels of reactive oxygen species. Opposite effects on these parameters were observed in the VIGS plants. RmERF54 was identified as a target of Dehydration-Responsive-Element-Binding factor (RmDREB1E). Taken together, provide new information concerning the molecular mechanisms by which RmERF54 regulates cold tolerance.


Assuntos
Proteínas de Plantas , Rosa , Proteínas de Plantas/metabolismo , Rosa/genética , Antioxidantes/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Resposta ao Choque Frio , Temperatura Baixa , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico
2.
Neuroepidemiology ; : 1-9, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38815560

RESUMO

INTRODUCTION: Huntington's disease (HD) is a rare, inherited neurodegenerative disorder. Despite extensive research on symptom progression and sex differences in Western populations, little is known about these aspects within the Chinese context. The objective of this study was to investigate the temporal trends of symptoms in individuals with HD in China. METHODS: A nationwide cross-sectional study was conducted in Chinese individuals diagnosed with HD. Symptom progression over time, encompassing physical, psychiatric, and cognitive symptoms, was self-reported. We calculated the proportions of individuals who currently had each symptom by disease duration, and tested corresponding temporal trends by linear regression analyses. RESULTS: A total of 269 individuals diagnosed with HD were included. Specific symptoms were found to progress more significantly in males compared to females over time, including psychotic symptoms (p = 0.007), urinary incontinence (p = 0.013), reduced concentration (p = 0.005), font alteration (p = 0.029), atypical facial expression (p = 0.037), and suicidal ideation (p = 0.047). In terms of cognitive and psychiatric symptoms, no significant temporal trends were identified in females, while males demonstrated significant increasing trends, with reduced concentration (p = 0.005) and psychotic symptoms (p = 0.007) standing out. CONCLUSIONS: This study emphasizes the existence of sex-specific symptom progression in HD within the Chinese population, underscoring the importance of considering sex in clinical practice. Further research should investigate the mechanisms behind these differences and explore tailored treatment options.

3.
Neuroepidemiology ; 58(1): 31-36, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38142687

RESUMO

BACKGROUND: Huntington's disease (HD) poses a significant socio-economic burden globally. Existing research on HD's economic burden predominantly comes from Western settings, leaving a gap in data from Asian countries. This study aimed to assess the economic burden of HD in China and identify cost-driving factors. METHODS: This study used data from a 2019 nationwide cross-sectional survey of individuals affected by rare diseases in China. Data included socio-demographic characteristics, income, disease stage, health and social insurance coverage status, treatment-seeking behaviour, and costs. Logistic regression and linear regression were used to explore potential contributors to treatment-seeking behaviour and associated costs. RESULTS: Of the 269 individuals with HD included in this study, 80.6% were actively seeking treatment. The average annual direct medical cost, direct non-medical cost, and indirect cost were 3,265.65, 805.82, and 801.97 Euros, respectively. Compared to participants with early-stage HD, those with middle- or advanced-stage HD reported higher direct medical costs (coefficient 1,612.70, 95% confidence interval [CI]: [141.92, 3,083.48] and 2,398.58, 95% CI: [791.16, 4,006.00], respectively). However, the disease stage was not significantly associated with direct non-medical costs or indirect costs. CONCLUSIONS: This study provides crucial insights into the economic burden of HD in China. It emphasises a need for targeted policies that better cater to the financial needs of HD patients.


Assuntos
Doença de Huntington , Humanos , Estudos Transversais , Doença de Huntington/epidemiologia , Estresse Financeiro , Modelos Logísticos , China/epidemiologia , Efeitos Psicossociais da Doença , Custos de Cuidados de Saúde
4.
Protein Expr Purif ; 216: 106430, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38184160

RESUMO

Pq3-O-UGT2, derived from Panax quinquefolius, functions as a ginsenoside glucosyltransferase, utilizing UDP-glucose (UDPG) as the sugar donor to catalyze the glycosylation of Rh2 and F2. An essential step in comprehending its catalytic mechanism involves structural analysis. In preparation for structural analysis, we expressed Pq3-O-UGT2 in the Escherichia coli (E. coli) strain Rosetta (DE3). The recombinant Pq3-O-UGT2 was purified through Ni-NTA affinity purification, a two-step ion exchange chromatography, and subsequently size-exclusion chromatography (SEC). Notably, the purified Pq3-O-UGT2 showed substantial activity toward Rh2 and F2, catalyzing the formation of Rg3 and Rd, respectively. This activity was discernible within a pH range of 4.0-9.0 and temperature range of 30-55 °C, with optimal conditions observed at pH 7.0-8.0 and 37 °C. The catalytic efficiency of Pq3-O-UGT2 toward Rh2 and F2 was 31.43 s-1 mΜ-1 and 169.31 s-1 mΜ-1, respectively. We further crystalized Pq3-O-UGT2 in both its apo form and co-crystalized forms with UDPG, Rh2 and F2, respectively. High-quality crystals were obtained and X-ray diffraction data was collected for all co-crystalized samples. Analysis of the diffraction data revealed that the crystal of Pq3-O-UGT2 co-crystalized with UDP-Glc belonged to space group P1, while the other two crystals belonged to space group P212121. Together, this study has laid a robust foundation for subsequent structural analysis of Pq3-O-UGT2.


Assuntos
Ginsenosídeos , Panax , Ginsenosídeos/metabolismo , Glicosiltransferases , Uridina Difosfato Glucose , Panax/genética , Panax/química , Panax/metabolismo , Cristalização , Escherichia coli/genética , Escherichia coli/metabolismo
5.
Arterioscler Thromb Vasc Biol ; 43(1): e11-e28, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36412196

RESUMO

BACKGROUND: Elevated plasma Lp-PLA2 (lipoprotein-associated phospholipase A2) activity is closely associated with an increased risk of cardiovascular events. However, whether and how Lp-PLA2 is directly involved in the pathogenesis of atherosclerosis is still unclear. To examine the hypothesis that Lp-PLA2 could be a potential preventative target of atherosclerosis, we generated Lp-PLA2 knockout rabbits and investigated the pathophysiological functions of Lp-PLA2. METHODS: Lp-PLA2 knockout rabbits were generated using CRISPR/Cas9 system to assess the role of Lp-PLA2 in plasma lipids regulation and identify its underlying molecular mechanisms. Homozygous knockout rabbits along with wild-type rabbits were fed a cholesterol-rich diet for up to 14 weeks and their atherosclerotic lesions were compared. Moreover, the effects of Lp-PLA2 deficiency on the key cellular behaviors in atherosclerosis were assessed in vitro. RESULTS: When rabbits were fed a standard diet, Lp-PLA2 deficiency led to a significant reduction in plasma lipids. The decreased protein levels of SREBP2 (sterol regulatory element-binding protein 2) and HMGCR (3-hydroxy-3-methylglutaryl coenzyme A reductase) in livers of homozygous knockout rabbits indicated that the cholesterol biosynthetic pathway was impaired with Lp-PLA2 deficiency. In vitro experiments further demonstrated that intracellular Lp-PLA2 efficiently enhanced SREBP2-related cholesterol biosynthesis signaling independently of INSIGs (insulin-induced genes). When fed a cholesterol-rich diet, homozygous knockout rabbits exhibited consistently lower level of hypercholesterolemia, and their aortic atherosclerosis lesions were significantly reduced by 60.2% compared with those of wild-type rabbits. The lesions of homozygous knockout rabbits were characterized by reduced macrophages and the expression of inflammatory cytokines. Macrophages of homozygous knockout rabbits were insensitive to M1 polarization and showed reduced DiI-labeled lipoprotein uptake capacity compared with wild-type macrophages. Lp-PLA2 deficiency also inhibited the adhesion between monocytes and endothelial cells. CONCLUSIONS: These results demonstrate that Lp-PLA2 plays a causal role in regulating blood lipid homeostasis and Lp-PLA2 deficiency protects against dietary cholesterol-induced atherosclerosis in rabbits. Lp-PLA2 could be a potential target for the prevention of atherosclerosis.


Assuntos
Aterosclerose , Hiperlipidemias , Animais , Coelhos , 1-Alquil-2-acetilglicerofosfocolina Esterase/genética , Lipoproteína(a) , Fosfolipases , Células Endoteliais/metabolismo , Aterosclerose/genética , Aterosclerose/prevenção & controle , Lipídeos , Colesterol
6.
J Periodontal Res ; 59(2): 395-407, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38311599

RESUMO

OBJECTIVE: The study aimed to investigate the change of amyloid precursor protein (APP) processing and amyloid ß (Aß) metabolites in linking periodontitis to Alzheimer's disease (AD). BACKGROUND: Aß is one of the main pathological features of AD, and few studies have discussed changes in its expression in peripheral tissues or analyzed the relationship between the peripheral imbalance of Aß production and clearance. METHODS: A murine model of periodontitis was established by oral infection with Porphyromonas gingivalis (P. gingivalis). Micro-computed tomography (Micro-CT) was used to observe the destruction of the alveolar bone. Nested quantitative polymerase chain reaction (qPCR) was used to measure small quantities of P.gingivalis DNA in different tissues. Behavioral experiments were performed to measure cognitive function in the mice. The mRNA levels of TNF-α, IL-6, IL-8, RANKL, OPG, APP695, APP751, APP770, and BACE1 in the gingival tissues or cortex were detected by RT-PCR. The levels of Aß1-40 and Aß1-42 in gingival crevicular fluid (GCF) and plasma were tested by ELISA. RESULTS: P. gingivalis oral infection was found to cause alveolar bone resorption and impaired learning and memory. P.gingivalis DNA was detected in the gingiva, blood and cortex of the P.gingivalis group by nested qPCR (p < .05). The mRNA expression of TNF-α, IL-6, IL-8, RANKL/OPG, and BACE1 in the gingival tissue was significantly higher than that in the control group (p < .05). Similarly, upregulated mRNA levels of APP695 and APP770 were observed in the gingival tissuses and cortex of the P. gingivalis group (p < .05). The levels of Aß1-40 and Aß1-42 in the GCF and plasma of the P. gingivalis group were significantly higher than those in the control group (p < .05). CONCLUSION: P. gingivalis can directly invade the brain via hematogenous infection. The invasion of P. gingivalis could trigger an immune response and lead to an imbalance between Aß production and clearance in peripheral tissues, which may trigger an abnormal Aß metabolite in the brain, resulting in the occurrence and development of AD.


Assuntos
Perda do Osso Alveolar , Periodontite , Camundongos , Animais , Precursor de Proteína beta-Amiloide/genética , Porphyromonas gingivalis/metabolismo , Secretases da Proteína Precursora do Amiloide , Peptídeos beta-Amiloides/metabolismo , Fator de Necrose Tumoral alfa , Modelos Animais de Doenças , Microtomografia por Raio-X , Interleucina-6 , Interleucina-8 , Ácido Aspártico Endopeptidases , Periodontite/metabolismo , RNA Mensageiro/análise , DNA
7.
Oral Dis ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38923332

RESUMO

OBJECTIVES: Porphyromonas gingivalis-LPS regulated bone metabolism by triggering dysfunction of osteoblasts directly, and affecting activity of osteoclasts through intracellular communication. Exosome, as the mediator of intercellular communication, was important vesicle to regulate osteogenesis and osteoclastogenesis. This research was designed for investigating the mechanism of BMSCs-EXO in modulating osteoclastic activity under the P. gingivalis-LPS. MATERIALS AND METHODS: The cytotoxicity and osteogenic effects of P. gingivalis-LPS on BMSCs was evaluated, and then osteoclastic activity of RAW264.7 co-cultured with exosomes was detected. Besides, Affymetrix miRNA array and luciferase reporter assay were used to identify the target exosomal miRNA signal pathway. RESULTS: BMSCs' osteogenic differentiation and proliferation were decreased under 1 and 10 µg/mL P. gingivalis-LPS. Osteoclastic-related genes and proteins levels were promoted by P. gingivalis-LPS-stimulated BMSCs-EXO. Based on the miRNA microarray analysis, exosomal miR-151-3p was lessened in BMExo-LPS group, which facilitated osteoclastic differentiation through miR-151-3p/PAFAH1B1. CONCLUSIONS: Porphyromonas gingivalis-LPS could regulated bone metabolism by inhibiting proliferation and osteogenesis of BMSCs directly. Also, P. gingivalis-LPS-stimulated BMSCs-EXO promoted osteoclastogenesis via activating miR-151-3p/PAFAH1B1 signal pathway.

8.
Molecules ; 29(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38398628

RESUMO

Inhibiting the activity of intestinal α-glucosidase is considered an effective approach for treating type II diabetes mellitus (T2DM). In this study, we employed an in vitro enzymatic synthesis approach to synthesize four derivatives of natural products (NPs) for the discovery of therapeutic drugs for T2DM. Network pharmacology analysis revealed that the betulinic acid derivative P3 exerted its effects in the treatment of T2DM through multiple targets. Neuroactive ligand-receptor interaction and the calcium signaling pathway were identified as key signaling pathways involved in the therapeutic action of compound P3 in T2DM. The results of molecular docking, molecular dynamics (MD) simulations, and binding free energy calculations indicate that compound P3 exhibits a more stable binding interaction and lower binding energy (-41.237 kcal/mol) with α-glucosidase compared to acarbose. In addition, compound P3 demonstrates excellent characteristics in various pharmacokinetic prediction models. Therefore, P3 holds promise as a lead compound for the development of drugs for T2DM and warrants further exploration. Finally, we performed site-directed mutagenesis to achieve targeted synthesis of betulinic acid derivative. This work demonstrates a practical strategy of discovering novel anti-hyperglycemic drugs from derivatives of NPs synthesized through in vitro enzymatic synthesis technology, providing potential insights into compound P3 as a lead compound for anti-hyperglycemic drug development.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Simulação de Acoplamento Molecular , Inibidores de Glicosídeo Hidrolases/química , alfa-Glucosidases/metabolismo , Ácido Betulínico
9.
BMC Nurs ; 23(1): 255, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649929

RESUMO

BACKGROUND: Poor nurse-patient relationship poses an obstacle to care delivery, jeopardizing patient experience and patient care outcomes. Measuring nurse-patient relationship is challenging given its multi-dimensional nature and a lack of well-established scales. PURPOSE: This study aimed to develop a multi-dimensional scale measuring nurse-patient relationship in China. METHODS: A preliminary scale was constructed based on the existing literature and Delphi consultations with 12 nursing experts. The face validity of the scale was tested through a survey of 45 clinical nurses. This was followed by a validation study on 620 clinical nurses. Cronbach's α, content validity and known-group validity of the scale were assessed. The study sample was further divided into two for Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA), respectively, to assess the construct validity of the scale. RESULTS: The Nurse-Patient Relationship Scale (NPRS) containing 23 items was developed and validated, measuring five dimensions: nursing behavior, nurse understanding and respect for patient, patient misunderstanding and mistrust in nurse, communication with patient, and interaction with patient. The Cronbach's α of the NPRS ranged from 0.725 to 0.932, indicating high internal consistency. The CFA showed excellent fitness of data into the five-factor structure: χ2/df = 2.431, GFI = 0.933, TLI = 0.923, CFI = 0.939, IFI = 0.923, RMSEA = 0.070. Good content and construct validity are demonstrated through expert consensus and psychometric tests. CONCLUSION: The NPRS is a valid tool measuring nurse-patient relationship in China.

10.
Int Nurs Rev ; 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191960

RESUMO

AIM: This study tested the mediating role of the nurse-patient relationship and self-rated health in the effect of emotional labour on turnover intention among nurses in China. BACKGROUND: The underlying mechanism behind the effect of emotional labour on turnover intention remains inadequately understood. INTRODUCTION: Nurses with a high level of emotional labour are predisposed to experiencing poor health and tension in their relationships with patients, which may increase turnover intention. METHODS: A cross-sectional survey of 527 nurses in a public tertiary hospital in Qiqihar, located in China's Heilongjiang province, was conducted. Emotional labour and turnover intention were assessed using existing validated scales containing multiple items, while the nurse-patient relationship and self-rated health were assessed using single items, respectively. Baron and Kenny's causal steps and the Karlson/Holm/Breen method were adopted to test the mediating effects of the nurse-patient relationship and self-rated health in the association between emotional labour and turnover intention after adjusting for variations in sociodemographic and job characteristics. RESULTS: Emotional labour was positively associated with turnover intention. Self-rated poor health and a disharmonious nurse-patient relationship partially mediated the positive effect of emotional labour on turnover intention. CONCLUSIONS: Emotional labour significantly affects the turnover intention of nurses working in public tertiary hospitals in China, and this effect is partially mediated by self-rated health and the nurse-patient relationship. IMPLICATIONS FOR NURSING PRACTICE AND NURSING POLICY: Giving more attention to nurses' negative emotions and work attitudes is crucial. Developing comprehensive strategies for enhancing nurses' emotional management ability, promoting their physical and psychological well-being, and improving nurse-patient relationship to reduce nurses' turnover.

11.
J Virol ; 96(24): e0116722, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36468861

RESUMO

The correct formation of native disulfide bonds is critical for the proper structure and function of many proteins. Cellular disulfide bond formation pathways commonly consist of two parts: sulfhydryl oxidase-mediated oxidation and disulfide isomerase-mediated isomerization. Some large DNA viruses, such as baculoviruses, encode sulfhydryl oxidases, but viral disulfide isomerases have not yet been identified, although G4L in poxvirus has been suggested to serve such a function. Here, we report that the baculovirus core gene ac81 encodes a putative disulfide isomerase. ac81 is conserved in baculoviruses, nudiviruses, and hytrosaviruses. We found that AC81 homologs contain a typical thioredoxin fold conserved in disulfide isomerases. To determine the role of AC81, a series of Autographa californica nucleopolyhedrovirus (AcMNPV) bacmids containing ac81 knockout or point mutations was generated, and the results showed that AC81 is essential for budded virus production, multinucleocapsid occlusion-derived virus (ODV) formation, and ODV embedding in occlusion bodies. Nonreducing Western blot analysis indicated that disulfide bond formation in per os infectivity factor 5 (PIF5), a substrate of the baculoviral sulfhydryl oxidase P33, was abnormal when ac81 was knocked out or mutated. Pulldown assays showed that AC81 interacted with PIF5 and P33 in infected cells. In addition, two critical regions that harbor key amino acids for function were identified in AC81. Taken together, our results suggest that AC81 is a key component involved in the baculovirus disulfide bond formation pathway and likely functions as a disulfide isomerase. IMPORTANCE Many large DNA viruses, such as poxvirus, asfarvirus, and baculovirus, encode their own sulfhydryl oxidase to facilitate the disulfide bond formation of viral proteins. Here, we show that AC81 functions as a putative disulfide isomerase and is involved in multiple functions of the baculovirus life cycle. Interestingly, AC81 and P33 (sulfhydryl oxidase) are conserved in baculoviruses, nudiviruses, and hytrosaviruses, which are all insect-specific large DNA viruses replicating in the nucleus, suggesting that viral disulfide bond formation is an ancient mechanism shared by these viruses.


Assuntos
Baculoviridae , Isomerases de Dissulfetos de Proteínas , Proteínas Virais , Animais , Baculoviridae/enzimologia , Baculoviridae/genética , Dissulfetos , Isomerases de Dissulfetos de Proteínas/genética , Spodoptera , Proteínas Virais/genética , Tiorredoxinas
12.
J Virol ; 96(6): e0208521, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35044209

RESUMO

The cap-snatching endonuclease (EN) of segmented negative-strand RNA viruses (sNSVs) produces short capped primers for viral transcription by cleaving the host mRNAs. EN requires divalent metals as cofactors for nucleic acid substrates cleavage; however, the detailed mechanism of metal ion-dependent catalysis of ENs remains obscure. In this work, we reported the EN crystal structure of the Ebinur Lake virus (EBIV), an emerging mosquito-borne orthobunyavirus, and investigated its enzymatic properties and metal ion-based catalytic mechanism. In vitro biochemical data showed that EBIV EN is a specific RNA nuclease and prefers to cleave unstructured uridine-rich ssRNA. Structural comparison indicated that the overall structural architecture of EBIV EN is similar to that of other sNSV ENs, while the detailed active site configuration including the binding state of metal ions and the conformation of the LA/LB loop pair is different. Based on sequence conservation analysis, nine active site mutants were constructed, and seven crystal structures of them were determined. Mutations of active site residues associated with the two metal ions (Mn1 and Mn2) coordination abolished EN activity. Crystallographic analyses further revealed that none of these mutants bound two metal ions simultaneously in the active site. Importantly, we found that the perturbation of Mn1-coordination (metal site 1), resulted in the enhancement or elimination of Mn2-coordination (metal site 2). Taken together, our data provide structural evidence to support the two-metal-ion catalytic mechanism of EBIV EN and the correlation of metal binding at the two binding sites, which may be commonly shared by bunyaviruses or other sNSVs. IMPORTANCE The viral endonucleases (ENs) encoded by bunyaviruses and orthomyxoviruses play an essential role in initiating transcription by "snatching" capped primers from the host mRNAs. These ENs are metal-ion-dependent nucleases; however, the details of their catalytic mechanism remain elusive. Here, we reported high-resolution crystal structures of the wild-type and mutant ENs of a novel bunyavirus, the Ebinur Lake virus (EBIV), and revealed the structure and function relationship of EN. The EBIV EN exhibited differences in the details of active site structure compared to its homologues. Our data provided structural evidence to support a two-metal-ion catalytic mechanism of EBIV EN, and found the correlation of metal binding at both binding sites, which might reflect the dynamic structural properties that correlate to EN catalytic function. Taken together, our results revealed the structural characteristics of EBIV EN and made important implications for understanding the catalytic mechanism of cap-snatching ENs.


Assuntos
Endonucleases , Orthobunyavirus , Proteínas Virais , Animais , Catálise , Endonucleases/química , Endonucleases/genética , Endonucleases/metabolismo , Ativação Enzimática/genética , Mutação , Orthobunyavirus/enzimologia , Orthobunyavirus/genética , Capuzes de RNA/metabolismo , RNA Mensageiro/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo
13.
J Virol ; 96(7): e0217321, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35266805

RESUMO

The Bunyavirales contain many important human pathogens that lack an antiviral therapy. The cap-snatching endonuclease (EN) of segmented negative-strand RNA viruses is an attractive target for broad-spectrum antivirals due to its essential role in initiating viral transcription. L-742,001, a previously reported diketo acid inhibitor against influenza virus EN, demonstrated potent EN inhibition and antiviral activity on various bunyaviruses. However, the precise inhibitory mechanism of the compound is still poorly understood. We recently characterized a highly active EN from Ebinur Lake virus (EBIV), a newly identified member of the Orthobunyavirus genus, and obtained its high-resolution structures, paving the way for structure-guided inhibitor development. Here, nine L-742,001 derivatives were designed and synthesized de novo, and their structure-activity relationship with EBIV EN was studied. In vitro biochemical data showed that the compounds inhibited the EBIV EN activity with different levels and could be divided into three categories. Five representative compounds were selected for further cell-based antiviral assay, and the results largely agreed with those of the EN assays. Furthermore, the precise binding modes of L-742,001 and its derivatives in EN were revealed by determining the high-resolution crystal structures of EN-inhibitor complexes, which suggested that the p-chlorobenzene is essential for the inhibitory activity and the flexible phenyl has the greatest exploration potential. This study provides an important basis for the structure-based design and optimization of inhibitors targeting EN of segmented negative-strand RNA viruses. IMPORTANCE The Bunyavirales contain many important human pathogens such as Crimean-Congo hemorrhagic fever virus and Lassa virus that pose serious threats to public health; however, currently there are no specific antiviral drugs against these viruses. The diketo acid inhibitor L-742,001 is a potential drug as it inactivates the cap-snatching endonuclease (EN) encoded by bunyaviruses. Here, we designed and synthesized nine L-742,001 derivatives and assessed the structure-activity relationship using EN of the newly identified Ebinur Lake virus (EBIV) as a research model. Our results revealed that the p-chlorobenzene of this broad-spectrum EN inhibitor is crucial for the inhibitory activity and the flexible phenyl "arm" has the best potential for further optimization. As cap-snatching ENs are present not only in bunyaviruses but also in influenza viruses, our data provide important guidelines for the development of novel and more potent diketo acid-based antiviral drugs against those viruses.


Assuntos
Antivirais , Bunyaviridae , Endonucleases , Proteínas Virais , Antivirais/síntese química , Antivirais/farmacologia , Antivirais/uso terapêutico , Bunyaviridae/enzimologia , Infecções por Bunyaviridae/tratamento farmacológico , Infecções por Bunyaviridae/virologia , Endonucleases/metabolismo , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Humanos , Hidroxibutiratos/química , Hidroxibutiratos/farmacologia , Hidroxibutiratos/uso terapêutico , Piperidinas/química , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Relação Estrutura-Atividade , Proteínas Virais/metabolismo
14.
J Virol ; 96(14): e0080622, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35862697

RESUMO

Baculoviruses initiate oral infection in the highly alkaline midgut of insects via a group of envelope proteins called per os infectivity factors (PIFs). To date, no high-resolution structural information has been reported for any PIF. Here, we present the crystal structure of the PIF5 ectodomain (PIF5e) from Autographa californica multiple nucleopolyhedrovirus (AcMNPV) at a 2.2-Å resolution. It revealed an open cavity between the N-terminal E1 domain and the C-terminal E2 domain and a cysteine-rich region with three pairs of disulfide bonds in the E2 domain. Multiple conserved intramolecular interactions within PIF5 are essential for maintaining its tertiary structure. Two conserved arginines (Arg8 and Arg74) play critical roles in E1-E2 interactions, and mutagenesis analysis supported their crucial role in oral infection. Importantly, the reduction in the oral infectivity of the Arg8, Arg74, or cysteine mutant viruses was related to the proteolytic cleavage of PIF5 by the endogenous protease embedded in occlusion bodies during alkaline treatment. This suggested that the structural stability of PIF5 under physiological conditions in the insect midgut is critical for baculoviral oral infectivity. IMPORTANCEPer os infection mediated by PIFs is the highly complex mechanism by which baculoviruses initiate infection in insects. Previous studies revealed that multiple PIF proteins form a large PIF complex on the envelope of virions, while PIF5 functions independently of the PIF complex. Here, we report the crystal structure of AcMNPV PIF5e, which, to our knowledge, is the first atomic structure reported for a PIF protein. The structure revealed the precise locations of three previously proposed disulfide bonds and other conserved intramolecular interactions, which are important for the structural stability of PIF5 and are also essential for oral infectivity. These findings advance our understanding of the molecular mechanism of baculovirus oral infection under alkaline conditions.


Assuntos
Nucleopoliedrovírus , Proteínas do Envelope Viral , Animais , Cisteína/química , Dissulfetos/química , Insetos , Nucleopoliedrovírus/química , Nucleopoliedrovírus/genética , Conformação Proteica , Spodoptera , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética
15.
Crit Rev Biotechnol ; : 1-19, 2023 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-37574211

RESUMO

Novel natural products (NPs) and their derivatives are important sources for drug discovery, which have been broadly applied in the fields of agriculture, livestock, and medicine, making the synthesis of NPs and their derivatives necessarily important. In recent years, biosynthesis technology has received increasing attention due to its high efficiency in the synthesis of high value-added novel products and its advantages of green, environmental protection, and controllability. In this review, the technological advances of biosynthesis strategies in the discovery of novel NPs and their derivatives are outlined, with an emphasis on two areas of host engineering and in vitro enzymatic synthesis. In terms of hosts engineering, multiple microorganisms, including Streptomyces, Aspergillus, and Penicillium, have been used as the biosynthetic gene clusters (BGCs) provider and host strain for the expression of BGCs to discover new compounds over the past years. In addition, the use of in vitro enzymatic synthesis strategy to generate novel compounds such as triterpenoid saponins and flavonoids is also hereby described.

16.
Health Qual Life Outcomes ; 21(1): 123, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37968716

RESUMO

OBJECTIVES: Spinal muscular atrophy (SMA) is a rare monogenic neuromuscular disorder caused by loss of function mutations. Measuring health-related quality of life to support economic evaluations in this population is encouraged. However, empirical evidence on the performance of preference-based measures (PBMs) in individuals with SMA is limited. This study aimed to assess the psychometric properties of the EQ-5D-5L and the Patient-Reported Outcomes Measure Information System Preference measure (PROPr) in individuals with SMA. METHODS: The data used in this study were obtained via a web-based, cross-sectional survey. All participants completed the self-reporting EQ-5D-5L and PROMIS-29 questionnaires. Information about their socioeconomic and health status was also obtained. Ceiling and floor effects, convergent and divergent validity, known-group validity, and the agreement between the two measures were assessed. RESULTS: Strong ceiling and floor effects were observed for four dimensions of the EQ-5D-5L and three subscales, including pain intensity, pain interference, and physical function, of the PROMIS-29. All hypothesized associations between EQ-5D-5L/PROMIS-29 and other neuromuscular questions were confirmed, supporting good convergent validity. Moreover, both EQ-5D-5L and PROPr scores differentiated between impaired functional groups, demonstrating good discriminative ability. Poor agreement between the EQ-5D-5L and PROPr utility scores was observed. CONCLUSIONS: The EQ-5D-5L and PROPr both appear to be valid PBMs for individuals with SMA. However, PROPr yielded considerably lower utility scores than EQ-5D-5L and their agreement was poor. Therefore, these two PBMs may not be used interchangeably in economic evaluations of SMA-related interventions.


Assuntos
Atrofia Muscular Espinal , Qualidade de Vida , Humanos , Estudos Transversais , Nível de Saúde , Inquéritos e Questionários , Psicometria/métodos , Reprodutibilidade dos Testes
17.
BMC Public Health ; 22(1): 2007, 2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36324110

RESUMO

BACKGROUND: Local environmental factors are associated with health and healthcare-seeking behaviors. However, there is a paucity in the literature documenting the link between air pollution and healthcare-seeking behaviors. This study aimed to address the gap in the literature through a cross-sectional study of domestic migrants in China. METHODS: Data were extracted from the 2017 China Migrants Dynamic Survey (n = 10,051) and linked to the official air pollution indicators measured by particulate matter (PM2.5 and PM10) and air quality index (AQI) in the residential municipalities (n = 310) of the study participants over the survey period. Probit regression models were established to determine the association between air pollution and refraining from visiting health facilities after adjustment for variations in the predisposing, enabling and needs factors. Thermal inversion intensity was adopted as an instrumental variable to overcome potential endogeneity. RESULTS: One unit (µg/m3) increase in monthly average PM2.5 was associated with 1.8% increase in the probability of refraining from visiting health facilities. The direction and significance of the link remained unchanged when PM2.5 was replaced by AQI or PM10. Higher probability of refraining from visiting health facilities was also associated with overwork (ß = 0.066, p = 0.041) and good self-related health (ß = 0.171, p = 0.006); whereas, lower probability of refraining from visiting health facilities was associated with short-distance (inter-county) migration (ß=-0.085, p = 0.048), exposure to health education (ß=-0.142, p < 0.001), a high sense of local belonging (ß=-0.082, p = 0.018), and having hypertension/diabetes (ß=-0.169, p = 0.005). CONCLUSION: Air pollution is a significant predictor of refraining from visiting health facilities in domestic migrants in China.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Migrantes , Humanos , Estudos Transversais , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Material Particulado/efeitos adversos , Material Particulado/análise , China/epidemiologia , Instalações de Saúde , Exposição Ambiental/análise
18.
J Integr Plant Biol ; 64(9): 1739-1754, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35731022

RESUMO

The ginsenoside Rg3 found in Panax species has extensive pharmacological properties, in particular anti-cancer effects. However, its natural yield in Panax plants is limited. Here, we report a multi-modular strategy to improve yields of Rg3 in a Panax ginseng chassis, combining engineering of triterpene metabolism and overexpression of a lignin biosynthesis gene, phenylalanine ammonia lyase (PAL). We first performed semi-rational design and site mutagenesis to improve the enzymatic efficiency of Pq3-O-UGT2, a glycosyltransferase that directly catalyzes the biosynthesis of Rg3 from Rh2 . Next, we used clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) gene editing to knock down the branch pathway of protopanaxatriol-type ginsenoside biosynthesis to enhance the metabolic flux of the protopanaxadiol-type ginsenoside Rg3 . Overexpression of PAL accelerated the formation of the xylem structure, significantly improving ginsenoside Rg3 accumulation (to 6.19-fold higher than in the control). We combined overexpression of the ginsenoside aglycon synthetic genes squalene epoxidase, Pq3-O-UGT2, and PAL with CRISPR/Cas9-based knockdown of CYP716A53v2 to improve ginsenoside Rg3 accumulation. Finally, we produced ginsenoside Rg3 at a yield of 83.6 mg/L in a shake flask (7.0 mg/g dry weight, 21.12-fold higher than with wild-type cultures). The high-production system established in this study could be a potential platform to produce the ginsenoside Rg3 commercially for pharmaceutical use.


Assuntos
Ginsenosídeos , Panax , Ginsenosídeos/metabolismo , Lignina/metabolismo , Panax/química , Panax/genética , Panax/metabolismo , Fenilalanina Amônia-Liase/genética , Fenilalanina Amônia-Liase/metabolismo
19.
J Am Chem Soc ; 143(31): 12025-12037, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34320319

RESUMO

The ability of nanomotors to promote the deep penetration of themselves and the loaded drugs in diseased tissues has been proposed and confirmed. However, whether such motion behavior of the nanomotors can also promote deep penetration of micrometer-sized immune cells in the diseased microenvironment, which is important for the immunotherapy of some diseases, has not been mentioned. Herein, we construct a nitric oxide (NO)-driven nanomotor that can move in the tumor microenvironment, focusing on its motion behavior and the role of NO, the beneficial product released during movement from this kind of nanomotor, in regulating the infiltration behavior and activity of immune cells. It can be found that the drug-loaded nanomotors with both NO-releasing ability and motility can promote the normalization of the tumor vasculature system and the degradation of the intrinsic extracellular matrix (ECM), which can significantly improve the tumor infiltration ability of T cells in vivo. The efficiency of T-cell infiltration in tumor tissue in vivo increased from 2.1 to 28.2%. Both subcutaneous and intraperitoneal implantation tumor models can validate the excellent antitumor effect of drug-loaded NO-driven nanomotors. This combination of motility of the power source from nanomotors and their physiological function offers a design idea for therapeutic agents for the future immunotherapy of many diseases.


Assuntos
Neoplasias da Mama/terapia , Docetaxel/farmacologia , Nanoestruturas/química , Óxido Nítrico/química , Linfócitos T/efeitos dos fármacos , Animais , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Docetaxel/química , Feminino , Humanos , Imunoterapia , Células MCF-7 , Neoplasias Mamárias Experimentais/patologia , Neoplasias Mamárias Experimentais/terapia , Camundongos , Linfócitos T/imunologia , Microambiente Tumoral/efeitos dos fármacos
20.
Cancer Immunol Immunother ; 70(9): 2601-2616, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33576874

RESUMO

Glioma stem cells (GSCs) contribute to the malignant growth of glioma, but little is known about the interaction between GSCs and tumor microenvironment. Here, we found that intense infiltration of regulatory T cells (Tregs) facilitated the qualities of GSCs through TGF-ß secretion that helped coordinately tumor growth. Mechanistic investigations indicated that TGF-ß acted on cancer cells to induce the core cancer stem cell-related genes CD133, SOX2, NESTIN, MUSASHI1 and ALDH1A expression and spheres formation via NF-κB-IL6-STAT3 signaling pathway, resulting in the increased cancer stemness and tumorigenic potential. Furthermore, Tregs promoted glioma tumor growth, and this effect could be abrogated with blockade of IL6 receptor by tocilizumab which also demonstrated certain level of therapeutic efficacy in xenograft model. Additionally, expression levels of CD133, IL6 and TGF-ß were found to serve as prognosis markers of glioma patients. Collectively, our findings reveal a new immune-associated mechanism underlying Tregs-induced GSCs. Moreover, efforts to target this network may be an effective strategy for treating glioma.


Assuntos
Glioma/imunologia , Glioma/metabolismo , Células-Tronco Neoplásicas/metabolismo , Transdução de Sinais , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Animais , Anticorpos Monoclonais Humanizados/farmacologia , Biomarcadores , Autorrenovação Celular , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Glioma/mortalidade , Glioma/patologia , Humanos , Imunofenotipagem , Interleucina-6/metabolismo , Camundongos , NF-kappa B/metabolismo , Prognóstico , Fator de Transcrição STAT3 , Fator de Crescimento Transformador beta/metabolismo
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