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1.
Zhongguo Zhong Yao Za Zhi ; 49(12): 3204-3211, 2024 Jun.
Artigo em Zh | MEDLINE | ID: mdl-39041081

RESUMO

Ursolic acid has gradually attracted much attention due to its unique pharmacological activities and valuable market value in recent years. Currently, ursolic acid is mostly extracted from loquat leaves, but the plant extraction method has low yield and high cost, and chemical synthesis is not readily available, so the biosynthesis method provides a new source for ursolic acid. α-amyrin acts as the main precursor for the synthesis of ursolic acid, and its yield is positively correlated with ursolic acid yield. Oxidosqualene cyclase(OSC) belongs to a multigene family which can catalyze the common precursor 2,3-oxidosqualene to generate different types of triterpene backbones, and plays a decisive role in the synthesis of triterpenoids. However, there are fewer reported key genes catalyzing the synthesis of α-amyrin in medicinal plants, and the yield and proportion of α-amyrin in the catalyzed products have always been a focus of research. In this study, ItOSC2, MdOSC1, AaOSC2 and CrAS, four enzymes capable of catalyzing the production of α-amyrin from 2,3-oxidosqualene, were cloned from Iris tectorum, Malus domestica, Artemisia annua and Catharanthus roseus, subject to sequence alignment and phylogenetic tree analyses, and transformed into Saccharomyces cerevisiae as plasmids. After 7 days of fermentation, the yield and proportions of α-amyrin, ß-amyrin and ergosterol were measured. Finally, AaOSC2 with the best ability to catalyze the generation of α-amyrin was filtered out, providing a key gene element for the later construction of engineered yeast strains with high production of α-amyrin and ursolic acid.


Assuntos
Transferases Intramoleculares , Ácido Oleanólico , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/metabolismo , Ácido Oleanólico/química , Ácido Oleanólico/biossíntese , Clonagem Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Triterpenos/metabolismo , Triterpenos/química , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/metabolismo , Filogenia , Triterpenos Pentacíclicos
2.
Zhongguo Zhong Yao Za Zhi ; 47(12): 3208-3214, 2022 Jun.
Artigo em Zh | MEDLINE | ID: mdl-35851113

RESUMO

Uridine diphosphate rhamnose(UDP-Rha), a glycoside donor synthesized with the catalysis of rhamnose synthase(RHM), is one of the important elements in the synthesis of rhamnosides. In this study, we cloned a RHM gene from Citrus sinensis(CsRHM) and analyzed its bioinformatic information and functions in vitro. The results showed the gene consisted of an open reading frame of 2 007 bp encoding 668 amino acid residues. The deduced protein had a presumed molecular weight of 75.27 kDa, a theoretical isoelectric point of 6.97, and the characteristic signal sequences(GxxxGxxG/A and YxxxK) of the RHM family. Multiple sequence alignments and the phylogenetic tree demonstrated that CsRHM shared homology with other RHMs. The results of enzymatic reactions in vitro showed that the recombinant protein CsRHM catalyzed the conversion of UDP-Glu to UDP-Rha, with the kinetic parameters V_(max), K_m, K_(cat), and K_(cat)/K_m of 0.373 7 µmol·L~(-1)·min~(-1), 21.29 µmol·L~(-1), 0.24 s~(-1), and 1.13×10~4 s~(-1)·L·mol~(-1), respectively. This study is the first report about CsRHM with validated catalytic function in vitro, which provides a foundation for further research on the biosynthesis of UDP-Rha.


Assuntos
Citrus sinensis , Citrus sinensis/genética , Citrus sinensis/metabolismo , Clonagem Molecular , Filogenia , Ramnose/química , Ramnose/metabolismo , Açúcares de Uridina Difosfato
3.
Anesth Analg ; 131(5): 1599-1606, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33079884

RESUMO

BACKGROUND: Oxycodone has been shown to be an effective analgesic for early postoperative analgesia, especially for abdominal operations associated with severe visceral pain. However, the dose needed varies depending on the operation and application of multimodal analgesia, such as local ropivacaine wound infiltration. Therefore, we conducted this study to estimate the median effective dose (ED50) of oxycodone that provides analgesia for hysterectomy and myomectomy with local ropivacaine wound infiltration. METHODS: In this dose-finding study, the ED50 of oxycodone for postoperative analgesia was estimated separately for laparoscopic hysterectomy, transabdominal hysterectomy, laparoscopic myomectomy, and transabdominal myomectomy. We used the sequential allocation designed by Dixon. Trials were conducted simultaneously in the 4 surgical type groups. A predefined dose of oxycodone was injected 30 minutes before the end of the operation with an initial dose of 0.1 mg/kg. A series of trials were performed following the rule of a relative 10% increase in dose after inadequate analgesia and a relative 10% decrease in dose after adequate analgesia. The study was conducted until the collection of 7 crossover points was achieved. Local ropivacaine wound infiltration was administered during abdominal stitching. The mean blood pressure (MBP) and heart rate (HR) were analyzed to assess the hemodynamic changes associated with oxycodone administration. RESULTS: A total of 113 patients were included in the estimation of ED50: 28 each in the laparoscopic hysterectomy group and transabdominal myomectomy group, 27 in the transabdominal hysterectomy group, and 30 in the laparoscopic myomectomy group. The estimated oxycodone ED50 (95% confidence interval [CI]) after laparoscopic hysterectomy, transabdominal hysterectomy, laparoscopic myomectomy, and transabdominal myomectomy was 0.060 mg/kg (0.053-0.068), 0.079 mg/kg (0.072-0.086), 0.060 mg/kg (0.051-0.071), and 0.092 mg/kg (0.086-0.098), respectively, for postoperative analgesia with local ropivacaine wound infiltration. The ED50 of oxycodone was different between laparoscopic surgeries and transabdominal surgeries (P < .001). The MBP and HR before and after oxycodone injection were different, regardless of surgical type. CONCLUSIONS: The oxycodone ED50 for postoperative analgesia was lower for laparoscopic hysterectomy (0.060 mg/kg) and laparoscopic myomectomy (0.060 mg/kg) than for transabdominal hysterectomy (0.079 mg/kg) and transabdominal myomectomy (0.092 mg/kg) when combined with local ropivacaine wound infiltration. A single intravenous injection of oxycodone is associated with an acceptable decrease in MBP and HR within a short time.


Assuntos
Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/uso terapêutico , Anestésicos Locais/uso terapêutico , Histerectomia/efeitos adversos , Oxicodona/administração & dosagem , Oxicodona/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Ropivacaina/uso terapêutico , Miomectomia Uterina/efeitos adversos , Adulto , Anestesia Local , Anestésicos Locais/administração & dosagem , Pressão Sanguínea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Injeções Intravenosas , Laparoscopia , Pessoa de Meia-Idade , Medição da Dor , Estudos Prospectivos , Ropivacaina/administração & dosagem
5.
Chin Med ; 19(1): 3, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38178130

RESUMO

BACKGROUND: Prognosis is critically important in stroke cases, with angiogenesis playing a key role in determining outcomes. This study aimed to investigate the potential protective effects of Atractylenolide I (Atr I), Atractylenolide III (Atr III), and Paeoniflorin (Pae) in promoting angiogenesis following cerebral ischemia. METHODS: The bEnd.3 cell line was used to evaluate the effects of these three compounds on vascular endothelial cell proliferation, migration, and tube formation. Male C57BL/6 mice underwent transient middle cerebral artery occlusion (MCAO), followed by daily intragastric administration of the Chinese medicine compounds to assess their impact on brain protection and angiogenesis. In vivo experiments included measuring infarct size and assessing neurological function. Immunofluorescence staining and an angiogenesis antibody array were used to evaluate angiogenesis in ischemic brain tissue. Functional enrichment analysis was performed to further investigate the pathways involved in the protective effects of the compounds. Molecular docking analysis explored the potential binding affinity of the compounds to insulin-like growth factor 2 (IGF-2), and Western blotting was used to measure levels of angiogenesis-related proteins. RESULTS: In vitro, the combination of Atr I, Atr III, and Pae enhanced cell proliferation, promoted migration, and stimulated tube formation. In vivo, the combined treatment significantly facilitated neurological function recovery and angiogenesis by day 14. The treatment also increased levels of angiogenesis-related proteins, including IGF-2. Pearson correlation analysis revealed a strong positive association between IGF-2 levels in ischemic brain tissue and angiogenesis, suggesting a good affinity of the compounds for the IGF-2 binding site, as supported by molecular docking analysis. CONCLUSION: The administration of Atr I, Atr III, and Pae has shown significant enhancements in long-term stroke recovery in mice, likely due to the promotion of angiogenesis via increased activation of the IGF-2 pathway in ischemic brain tissue.

6.
Curr Neurovasc Res ; 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39364868

RESUMO

OBJECTIVE: Nearly half of Acute Ischemic Stroke (AIS) patients failed to achieve favorable outcomes despite successful reperfusion treatment. This phenomenon is referred to as Futile Recanalization (FR). Screening patients at risk of FR is vital for stroke management. Previous studies reported the diagnostic value of alkaline phosphatase (ALP) levels in certain aspects of stroke prognosis. However, the association between serum ALP level and FR among AIS patients treated with thrombectomy remained unclear. METHODS: We screened stroke patients who underwent thrombectomy at our center from January 2017 to June 2021, and those who achieved successful reperfusion (modified Thrombolysis in Cerebral Infarction score=3) were ultimately analyzed. Demographic information, vascular risk factors, and laboratory test results were collected at admission. The 3-month unfavorable outcome was defined as a modified Rankin Scale score of 3 to 6. The effect of ALP levels on FR was investigated with a logistic regression model. RESULTS: Of 788 patients who underwent thrombectomy, 277 achieved successful reperfusion. Among them, 142 patients (51.3%) failed to realize favorable outcomes at 3 months. After adjusting for confounding variables, higher ALP levels (p =0.002) at admission were independently associated with unfavorable outcomes at three months. Adding ALP values to conventional risk factors improved the performance of prediction models for FR. CONCLUSION: The current study found that the serum ALP levels at admission emerged as a potential biomarker for futile reperfusion in stroke patients undergoing thrombectomy. Further studies are warranted to confirm the clinical applicability of ALP level for futile recanalization prediction.

7.
Brain Circ ; 10(2): 174-183, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39036291

RESUMO

BACKGROUND: Hemorrhagic shock (HS) causes severe organ damage, worsened by high-altitude conditions with lower oxygen and temperatures. Existing research lacks specific insights on brain and heart damage under these conditions. This study hypothesizes that high-altitude and cold (HAC) environments exacerbate HS-induced damage in the brain and heart, aiming to improve treatment strategies. MATERIALS AND METHODS: Twenty-four male Sprague-Dawley (SD) rats (200-250 g of weight) were randomly assigned into sham, HS + normal, HS + HAC (4,000 m), and HS + HAC (6,000 m). The HS model was established in SD rats (35% loss of total blood volume), and histopathological injuries of the brain and heart were detected using hematoxylin and eosin staining, Sirius red staining, and immunohistochemistry. Apoptosis of the brain and heart tissues was detected by terminal transferase-mediated dUTP nick end labeling (TUNEL) immunofluorescence staining. To determine the levels of tumor necrosis factor-α (TNF-α), interferon-gamma (IFN-γ), monocyte chemoattractant protein-1 (Mcp-1), BCL2-associated X (BAX), and myeloid cell leukemia-1 (Mcl-1) protein, western blotting assay was used. RESULTS: The HAC environment induced pathological damage to the brain and heart and aggravated the degree of cardiac fibrosis in HS rats. However, it did not cause apoptosis of the brain and heart. In addition, it upregulated TNF-α, IFN-γ, Mcp-1, and BAX protein levels, but downregulated Mcl-1 protein levels (P < 0.05). CONCLUSIONS: The HAC environment aggravated the degree of brain and heart damage in HS rats, which may be related to neuron nucleus pyknosis, myocardial fibrosis, and inflammatory and apoptosis activation.

8.
Curr Neurovasc Res ; 21(1): 6-14, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38141190

RESUMO

BACKGROUND: Approximately half of AIS patients have an unfavorable outcome even after complete reperfusion. White blood cell (WBC) count to mean platelet volume (MPV) ratio (WMR) may be a promising predictive factor for futile recanalization. This study aimed to determine the predictive value of WMR in identifying individuals at higher risk of futile recanalization. METHODS: In this retrospective cohort study, 296 patients who achieved complete reperfusion after endovascular treatment (EVT) were included in the analysis. WBC count and MPV were collected at admission. Multivariable logistic regression was used to examine the independent association of the WMR with functional outcomes at three months. Net reclassification improvement (NRI) and integrated discrimination improvement (IDI) analyses were used to compare the accuracy of WMR for predicting futile recanalization. RESULTS: The adjusted odds ratios for the fourth quartile of WMR were 3.142 (95% CI 1.405- 7.027, P = 0.005) for unfavorable outcomes at 3 months in comparison with the first quartile. The inclusion of WMR in the traditional model enabled a more accurate prediction of unfavorable outcomes (NRI 0.250, P = 0.031; IDI 0.022, P = 0.017). CONCLUSION: Elevated WMR at admission was independently associated with futile recanalization among AIS patients who received EVT and might be useful in identifying futile recanalization.


Assuntos
Procedimentos Endovasculares , AVC Isquêmico , Volume Plaquetário Médio , Trombectomia , Humanos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , AVC Isquêmico/sangue , AVC Isquêmico/cirurgia , Trombectomia/métodos , Trombectomia/tendências , Procedimentos Endovasculares/métodos , Estudos Retrospectivos , Contagem de Leucócitos , Idoso de 80 Anos ou mais , Estudos de Coortes , Resultado do Tratamento , Valor Preditivo dos Testes
9.
Talanta ; 272: 125784, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38364555

RESUMO

Fat mass and obesity-associated protein (FTO) is a crucial eraser of RNA N6- methyladenosine (m6A) modification, and abnormal FTO expression level is implicated in pathogenesis of numerous cancers. Herein, we demonstrate the construction of a label-free fluorescent biosensor for homogeneous detection of m6A eraser FTO in breast cancer tissues. When FTO is present, it specifically erases the methyl group in m6A, inducing the cleavage of demethylated DNA by endonuclease DpnII and the generation of a single-stranded DNA (ssDNA) with a 3'-hydroxyl group. Subsequently, terminal deoxynucleotidyl transferase (TdT) promotes the incorporation of dTTPs into the ssDNA to obtain a long polythymidine (T) DNA sequence. The resultant long poly (T) DNA sequence can act as a template to trigger hyperbranched strand displacement amplification (HSDA), yielding numerous DNA fragments that may be stained by SYBR Gold to produce an enhanced fluorescence signal. This biosensor processes ultrahigh sensitivity with a detection limit of 1.65 × 10-10 mg/mL (2.6 fM), and it can detect the FTO activity in a single MCF-7 cell. Moreover, this biosensor can screen the FTO inhibitors, evaluate enzyme kinetic parameters, and discriminate the FTO expression levels in the tissues of breast cancer patients and healthy persons.


Assuntos
Técnicas Biossensoriais , Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , DNA , DNA de Cadeia Simples/genética , RNA , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética
10.
CNS Neurosci Ther ; 30(2): e14346, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37435771

RESUMO

BACKGROUND: Ischemic stroke (IS) is a cerebrovascular disease with high incidence and mortality. White matter repair plays an important role in the long-term recovery of neurological function after cerebral ischemia. Neuroprotective microglial responses can promote white matter repair and protect ischemic brain tissue. AIMS: The aim of this study was to investigate whether hypoxic postconditioning (HPC) can promote white matter repair after IS, and the role and mechanism of microglial polarization in white matter repair after HPC treatment. MATERIALS & METHODS: Adult male C57/BL6 mice were randomly divided into three groups: Sham group (Sham), MCAO group (MCAO), and hypoxic postconditioning group (HPC). HPC group were subjected to 45 min of transient middle cerebral artery occlusion (MCAO) immediately followed by 40 min of HPC. RESULTS: The results showed that HPC reduced the proinflammatory level of immune cells. Furthermore, HPC promoted the transformation of microglia to anti-inflammatory phenotype on the third day after the procedure. HPC promoted the proliferation of oligodendrocyte progenitors and increased the expression of myelination-related proteins on the 14th day. On the 28th day, HPC increased the expression of mature oligodendrocytes, which enhanced myelination. At the same time, the motor neurological function of mice was restored. DISCUSSION: During the acute phase of cerebral ischemia, the function of proinflammatory immune cells was enhanced, long-term white matter damage was aggravated, and motor sensory function was decreased. CONCLUSION: HPC promotes protective microglial responses and white matter repair after MCAO, which may be related to the proliferation and differentiation of oligodendrocytes.


Assuntos
Lesões Encefálicas , Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Substância Branca , Camundongos , Masculino , Animais , Microglia/metabolismo , AVC Isquêmico/metabolismo , Substância Branca/metabolismo , Isquemia Encefálica/metabolismo , Lesões Encefálicas/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Hipóxia/metabolismo , Acidente Vascular Cerebral/metabolismo
11.
Heliyon ; 10(4): e25916, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38390161

RESUMO

Objective: This study aimed to explore the impact of late night shift work on the functional outcomes of patients with acute ischemic stroke (AIS) treated with endovascular thrombectomy (EVT). Methods: Consecutive AIS patients who underwent EVT between June 2019 and June 2021 were enrolled and divided into non-night shift work and night shift work groups based on their occupational histories. The primary outcome was the modified Rankin Scale score defined 3-month functional outcome. The secondary outcomes were 3-month mortality, symptomatic intracerebral hemorrhage (sICH), ICH and early recanalization. Results: A total of 285 patients were enrolled, 35 patients (12.3%) were night shift workers, who were younger (P < 0.001) and had a significantly higher prevalence of smoking (P < 0.001), hyperlipidemia (P = 0.002), coronary heart disease (P = 0.031), and atrial fibrillation (P < 0.001). The 3-month favorable outcomes were achieved in 44.8% and 25.7% of patients in the non-night shift work and night shift work groups, respectively (adjusted odds ratio [OR]: 0.24, 95% CI: 0.10-0.57; adjusted P = 0.001). No difference was found in 3-month mortality (adjusted OR: 0.43; 95% CI: 0.14-1.25, adjusted P = 0.121), rates of ICH (adjusted OR: 0.73; 95% CI: 0.33-1.60; adjusted P = 0.430), sICH (adjusted OR: 0.75; 95% CI: 0.34-1.67; adjusted P = 0.487), or early successful recanalization (adjusted OR: 0.42; 95% CI: 0.12-1.56; adjusted P = 0.197). These results were consistent after PSM analysis. Conclusion: Our findings suggest that late night shift work is significantly associated with unfavorable outcomes in patients with AIS after EVT.

12.
CNS Neurosci Ther ; 29(2): 516-524, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36550592

RESUMO

Ischemic stroke is one of the major disabling health-care problem and multiple different approaches are needed to enhance rehabilitation, in which neural repair is the structural basement. Remote ischemic conditioning (RIC) is a strategy to trigger endogenous protect. RIC has been reported to play neuroprotective role in acute stage of stroke, but the effect of RIC on repair process remaining unclear. Several studies have discovered some overlapped mechanisms RIC and neural repair performs. This review provides a hypothesis that RIC is a potential therapeutic strategy on stroke rehabilitation by evaluating the existing evidence and puts forward some remaining questions to clarify and future researches to be performed in the field.


Assuntos
Precondicionamento Isquêmico , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/terapia
13.
Prog Neurobiol ; 230: 102514, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37574039

RESUMO

Vascular cognitive impairment (VCI) due to chronic cerebral hypoperfusion (CCH), is the second leading cause of dementia. Although synaptic impairment plays a critical role in VCI, its exact mechanism remains unknown. Our previous research revealed that remote ischemic conditioning (RIC) could alleviate cognitive decline resulting from CCH, however, its effects on synaptic impairment remain unclear. In this study, we confirmed that RIC alleviated both cognitive decline and its associated synaptic dysfunction caused by CCH. RNA sequencing revealed that CCH increased in miR-218a-5p expression, which was decreased by RIC. Elevated miR-218a-5p levels limited the benefits of RIC, however, inhibiting miR-218a-5p in hippocampal CA1 neurons rescued synaptic dysfunction. Additionally, we found that SHANK2 is a downstream target of miR-218a-5p, and inhibiting SHANK2 expression reduced the alleviation caused by hypoxic conditioning in synaptic impairment in vitro. In conclusion, our results suggested that RIC alleviated synaptic impairment via the miR-218a-5p/SHANK2 pathway, which could be a potential biomarker or therapeutic target for cognitive impairment caused by CCH.


Assuntos
Isquemia Encefálica , Disfunção Cognitiva , MicroRNAs , Humanos , Isquemia Encefálica/complicações , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/terapia , Disfunção Cognitiva/metabolismo , Hipocampo/metabolismo , MicroRNAs/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo
14.
Neurologist ; 28(6): 367-372, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37247412

RESUMO

BACKGROUND: Remote ischemic conditioning (RIC) has shown an impressive neuroprotective effect on acute ischemic stroke (AIS) in animal experiments. But whether chronic RIC improves long-term functional outcomes remains unclear. MATERIALS AND METHODS: We performed a non-randomized controlled trial. Eligible patients (aged 18 -80 y) with hemiplegia caused by AIS were allocated to the RIC group and the control group. All participants received normal protocol rehabilitation therapy. Patients in the RIC group underwent RIC twice daily for 90 days. The outcome included the 90-day Fugl-Meyer Assessment (FMA) scores and modified Rankin's scale (mRS) scores, as well as changes in angiogenesis-related factors in serum from baseline to 90 days. RESULTS: Twenty-seven patients were included in the analysis (13 in the RIC group and 14 in the control group). There was no significant difference in 90-day total FMA scores between the two groups. Lower limb FMA scores at day 90 were significantly higher in the RIC group (32.8±8.7 vs. 24.8±5.4, adjusted P =0.042). The proportion of favorable outcome (mRS<2) was higher in the RIC group than that in the control group, but no significant difference was detected (8 [61.5%] vs. 7 [50%], P =0.705). A significant increase has been found in the level of epidermal growth factor (EGF) in serum (9.4 [1.1 to 25.7] vs. -8.7 [-15.1 to 4.7], P =0.036) after chronic RIC procedure. CONCLUSION: This study investigated the role that RIC plays in AIS recovery, especially in motor function. RIC may have beneficial effects on lower limbs recovery by enhancing the EGF level. The effect of RIC on motor recovery should be further validated in future studies.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Animais , Humanos , Fator de Crescimento Epidérmico , Acidente Vascular Cerebral/terapia , Resultado do Tratamento
15.
Neuroscience ; 526: 35-47, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37331689

RESUMO

Although hypoxic postconditioning (HPC) has a protective effect on ischemic stroke, its effect on angiogenesis after ischemic stroke is still unclear. This study was designed to investigate the effects of HPC on angiogenesis after ischemic stroke and to preliminarily study the mechanism involved. Oxygen-glucose deprivation (OGD)-intervened bEnd.3 (mouse brain-derived Endothelial cell. 3) was used to simulate cerebral ischemia. Cell counting kit-8 (CCK-8), Cell BrdU proliferation, wound healing, Transwell and tube formation assays were used to evaluate the effect of HPC on the cell viability, proliferation, migration (horizontal and vertical migration), morphogenesis and tube formation of bEnd.3. A middle cerebral artery occlusion (MCAO) model was made in C57 mice to simulate focal cerebral ischemia. Rod rotation test, corner test, modified neurological severity score (mNSS), and balance beam walking test were used to evaluate the effect of HPC on the neurological impairment of mice. Immunofluorescence staining was used to evaluate the effect of HPC on angiogenesis in mice. The angiogenesis-related proteins were evaluated and quantified using western blot. Results showed that HPC significantly promoted proliferation, migration and tube formation of bEnd.3. HPC significantly reversed the neurological deficit of MCAO mice. Moreover, HPC significantly promoted angiogenesis in the peri-infarct area, and angiogenesis was found to be positively correlated with the improvement of neurological impairment. The HPC mice showed higher PLCλ and ALK5 than did MCAO. We conclude that HPC improves the neurological deficit caused by focal cerebral ischemia by promoting angiogenesis. Furthermore, the effect of HPC on improving angiogenesis may be related to PLCλ and ALK5.


Assuntos
Isquemia Encefálica , Pós-Condicionamento Isquêmico , AVC Isquêmico , Acidente Vascular Cerebral , Camundongos , Animais , Isquemia Encefálica/metabolismo , Infarto da Artéria Cerebral Média , Morfogênese , Acidente Vascular Cerebral/metabolismo
16.
Anal Chim Acta ; 1279: 341796, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37827689

RESUMO

The METTL3/14 complex is an important RNA N6-Methyladenosine (m6A) methyltransferase in organisms, and the abnormal METTL3/14 complex activity is associated with the pathogenesis and various cancers. Sensitive detection of METTL3/14 complex is essential to tumor pathogenesis study, cancer diagnosis, and anti-cancer drug discovery. However, traditional methods for METTL3/14 complex assay suffer from poor specificity, costly antibodies, unstable RNA substrates, and low sensitivity. Herein, we construct a single quantum dot (QD)-based förster resonance energy transfer (FRET) biosensor for sensitive detection of METTL3/14 complex activity. In the presence of METTL3/14 complex, it catalyzes the methylation of adenine in the substrate probe, leading to the formation of m6A that protects the substrate probes from MazF-mediated cleavage. The hybridization of methylated DNA substrate with biotinylated capture probe initiates polymerization reaction to obtain a biotinylated double-stranded DNA (dsDNA) with the incorporation of numerous Cy5 fluorophores. Subsequently, the Cy5-incorporated dsDNA can self-assembly onto the 605QD surface to form the 605QD-dsDNA-Cy5 nanostructure, causing FRET between 605QD donor and Cy5 acceptor. This biosensor has excellent sensitivity with a limit of detection (LOD) of 3.11 × 10-17 M, and it can measure the METTL3/14 complex activity in a single cell. Moreover, this biosensor can be used to evaluate the METTL3/14 complex kinetic parameters and screen potential inhibitors. Furthermore, it can differentiate the METTL3/14 complex expression in healthy human tissues and breast cancer patient tissues, providing a powerful tool for cancer pathogenesis study, clinical diagnosis, prognosis monitoring, and drug discovery.


Assuntos
Técnicas Biossensoriais , Neoplasias da Mama , Pontos Quânticos , Humanos , Feminino , Pontos Quânticos/química , Neoplasias da Mama/diagnóstico , DNA/química , Metiltransferases , RNA
17.
J Neurol ; 270(4): 2084-2095, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36596867

RESUMO

OBJECTIVES: To investigate the relationship between the initiation time of anticoagulation after endovascular treatment (EVT) and the outcomes in atrial fibrillation (AF)-related acute ischemic stroke (AIS) patients. METHODS: In this prospective registry study, from March 2013 to June 2022, patients with anterior circulation territories AF-related AIS who underwent EVT within 24 h were included. The primary outcome was favorable [modified Rankin Scale (mRS) 0-1) at ninety days and the secondary outcome was hemorrhage events after anticoagulants. Factors affecting the outcomes were pooled into multivariate regression and ROC curve analysis. RESULTS: Of 234 eligible patients, there were 63 (26.9%) patients achieved a favorable outcome. The symptomatic intracranial hemorrhage (sICH), ICH, and systemic hemorrhage events after anticoagulants occurred in 8 (3.4%), 28 (12.0%), and 39 (16.7%) patients, severally. A longer EVT to anticoagulation time (p = 0.033) was associated with an unfavorable outcome (mRS 3-6). An earlier EVT to anticoagulation time was the independent risk factor of sICH (p = 0.043), ICH (p = 0.005), and systemic hemorrhage (p = 0.005). There was no significant difference in recurrent AIS/ transient ischemic attack (TIA) or mortality among patients who started anticoagulation at ≤ 4 days, ≥ 15 days, or 4 to 15 days. The optimum cut-off for initiating anticoagulants to predict a favorable outcome and hemorrhage events was 4.5 days and 3.5 days after EVT, respectively. CONCLUSIONS: In AF-related AIS, the time of EVT to anticoagulation is an independent factor of the functional outcome and hemorrhage events after anticoagulation. The optimal initiate time of anticoagulant after EVT is 4.5 days. CLINICALTRIALREGISTER: NCT03754738.


Assuntos
Fibrilação Atrial , Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Anticoagulantes/efeitos adversos , Fibrilação Atrial/complicações , Fibrilação Atrial/cirurgia , Isquemia Encefálica/complicações , Isquemia Encefálica/cirurgia , Procedimentos Endovasculares/efeitos adversos , Hemorragia , Hemorragias Intracranianas/etiologia , AVC Isquêmico/complicações , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/cirurgia , Trombectomia/efeitos adversos , Resultado do Tratamento
18.
Chem Commun (Camb) ; 58(62): 8662-8665, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35822530

RESUMO

We have developed a simple and rapid mix-and-read assay for the sensitive detection of O6-methylguanine DNA methyltransferase (MGMT) activity based on exonuclease III-assisted signal amplification under completely isothermal conditions (37 °C). This method is very simple and rapid (60 min) with ultrahigh sensitivity and good specificity, and it can detect MGMT activity at the single-cell level. Moreover, this method can be applied for the screening of MGMT inhibitors and the discrimination of MGMT in different cancer cells.


Assuntos
Guanina , O(6)-Metilguanina-DNA Metiltransferase , DNA , Guanina/análogos & derivados , O(6)-Metilguanina-DNA Metiltransferase/genética
19.
J Agric Food Chem ; 70(11): 3467-3476, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35258300

RESUMO

Azadirachtin, a limonoid isolated from the neem tree, has attracted considerable interest due to its excellent performance in pest control. Studies have also reported pharmaceutical activities of dihydroniloticin, an intermediate in azadirachtin biosynthesis, but these pharmaceutical activities could not be validated due to the limited supply. In this study, AiCYP71CD2 was first identified as involved in azadirachtin biosynthesis in neem by expressing it in Nicotiana benthamiana and yeast (Saccharomyces cerevisiae). Homology modeling and molecular docking analysis revealed that AiCYP71CD2 may exhibit a higher ability in catalyzing tirucalla-7,24-dien-3ß-ol into dihydroniloticin compared with MaCYP71CD2 from Melia azedarach L. G310 was identified as the critical residue responsible for the higher catalytic ability of AiCYP71CD2. Condon-Optimized AiCYP71CD2 greatly improved the catalytic efficiency in yeast. De novo dihydroniloticin production using the novel AiCYP71CD2 was achieved by constructing the S. cerevisiae DI-3 strain, and the titer could reach up to 405 mg/L in a fermentor, which was an alternative source for dihydroniloticin.


Assuntos
Azadirachta , Melia azedarach , Azadirachta/química , Azadirachta/genética , Engenharia Metabólica , Simulação de Acoplamento Molecular , Saccharomyces cerevisiae/genética
20.
Artigo em Inglês | MEDLINE | ID: mdl-35035503

RESUMO

PURPOSE: Danggui Shaoyao San (DSS) was developed to treat the ischemic stroke (IS) in patients and animal models. The purpose of this study was to explore its active compounds and demonstrate its mechanism against IS through network pharmacology, molecular docking, and animal experiment. METHODS: All the components of DSS were retrieved from the pharmacology database of TCM system. The genes corresponding to the targets were retrieved using OMIM, CTD database, and TTD database. The herb-compound-target network was constructed by Cytoscape software. The target protein-protein interaction network was built using the STRING database. The core targets of DSS were analyzed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Then, we achieved molecular docking between the hub proteins and the key active compounds. Finally, animal experiments were performed to verify the core targets. Triphenyltetrazolium chloride (TTC) staining was used to calculate the infarct size in mice. The protein expression was determined using the Western blot. RESULTS: Compound-target network mainly contained 51 compounds and 315 corresponding targets. Key targets contained MAPK1, SRC, PIK3R1, HRAS, AKT1, RHOA, RAC1, HSP90AA1, and RXRA FN1. There were 417 GO items in GO enrichment analysis (p < 0.05) and 119 signaling pathways (p < 0.05) in KEGG, mainly including negative regulation of apoptosis, steroid hormone-mediated signaling pathway, neutrophil activation, cellular response to oxidative stress, and VEGF signaling pathway. MAPK1, SRC, and PIK3R1 docked with small molecule compounds. According to the Western blot, the expression of p-MAPK 1, p-AKT, and p-SRC was regulated by DSS. CONCLUSIONS: This study showed that DSS can treat IS through multiple targets and routes and provided new insights to explore the mechanisms of DSS against IS.

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