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1.
Int J Mol Sci ; 25(5)2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38474274

ABSTRACT

Real-time quantitative PCR (qRT-PCR) is a pivotal technique for gene expression analysis. To ensure reliable and accurate results, the internal reference genes must exhibit stable expression across varied experimental conditions. Currently, no internal reference genes for Camellia impressinervis have been established. This study aimed to identify stable internal reference genes from eight candidates derived from different developmental stages of C. impressinervis flowers. We employed geNorm, NormFinder, and BestKeeper to evaluate the expression stability of these candidates, which was followed by a comprehensive stability analysis. The results indicated that CiTUB, a tubulin gene, exhibited the most stable expression among the eight reference gene candidates in the petals. Subsequently, CiTUB was utilized as an internal reference for the qRT-PCR analysis of six genes implicated in the petal pigment synthesis pathway of C. impressinervis. The qRT-PCR results were corroborated by transcriptome sequencing data, affirming the stability and suitability of CiTUB as a reference gene. This study marks the first identification of stable internal reference genes within the entire genome of C. impressinervis, establishing a foundation for future gene expression and functional studies. Identifying such stable reference genes is crucial for advancing molecular research on C. impressinervis.


Subject(s)
Camellia , Camellia/genetics , Gene Expression Profiling/methods , Transcriptome , Real-Time Polymerase Chain Reaction/methods , Flowers/genetics , Reference Standards
2.
Medicine (Baltimore) ; 102(36): e35099, 2023 Sep 08.
Article in English | MEDLINE | ID: mdl-37682162

ABSTRACT

OBJECTIVE: To evaluate the efficacy and safety of short-term high-dose of dual antiplatelet therapy after 0.6 mg/kg rt-PA intravenous thrombolysis for acute ischemic stroke (AIS). METHODS: All 208 patients with AIS were randomized into group 1 (103 cases, after 0.6 mg/kg rt-PA, 300 mg of oral aspirin(ASP) q.d. and 225 mg of oral clopidogrel (CLO) q.d. for for 5 days, then 100 mg of oral ASP q.d. for the next 85 days and 75 mg of oral CLO q.d. for the next 16 days) and group 2 (105 cases, after 0.9 mg/kg rt-PA, 100 mg of oral ASP q.d. for 90 days and 75 mg of oral CLO q.d. for 21 days).The efficacy index was the mRS score, NIHSS score and recurrence risk of stroke, while the safety index was the incidence of bleeding events and mortality. All parameters were evaluated at 30 and 90 days after thrombolysis. Patients whose characteristics may provide the best treatment benefit were further analyzed using the logistic regression model in group 1. RESULTS: The proportion of mRS scores between 0 and 1 in group 1 was higher than that in group 2 at both 30 days (44.7% vs 32.4%, P < .05) and 90 days (50.5% vs 35.2%, P < .05). Compared to group 2, the proportion of NIHSS scores less than 4 was significantly higher in group 1 at both 30 days (37.9% vs 25.7%, P < .05) and 90 days (46.6% vs 30.5%, P < .05). At 90 days, Group 1 had a lower stroke recurrence risk than Group 2 (3.9% vs 10.5%, P < .05). The incidence of SICH was significantly different between the 2 groups at both 30 days (2.9% vs 9.5%, P < .05) and 90 days (2.9% vs 10.5%, P < .05). However, other bleeding events and mortality rates were not significantly different between the 2 groups. The lower the baseline NIHSS score and the shorter the OTT, the more favorable the outcomes obtained at 90 days. CONCLUSIONS: Compared to standard doses, short term high-dose dual antiplatelet therapy after 0.6 mg/kg rt-PA intravenous thrombolysis may be a good choice for AIS patients.


Subject(s)
Ischemic Stroke , Stroke , Humans , Ischemic Stroke/drug therapy , Platelet Aggregation Inhibitors/adverse effects , Stroke/drug therapy , Tissue Plasminogen Activator/adverse effects , Clopidogrel/adverse effects , Thrombolytic Therapy/adverse effects
3.
Front Neurol ; 13: 806013, 2022.
Article in English | MEDLINE | ID: mdl-35273556

ABSTRACT

Objective: To investigate the effects of blood glucose variability on early therapeutic effects after intravenous thrombolysis with alteplase and the levels of serum inflammatory factors in patients with acute ischemic stroke (AIS). Methods: We enrolled AIS patients who received intravenous thrombolysis within 4.5 h of the onset of symptoms. Clinical data, including the National Institutes of Health Stroke Scale (NIHSS), glycosylated hemoglobin, mean blood glucose, standard deviation of blood glucose, mean amplitude of glycemic excursion, mean variation coefficient of blood glucose, interleukin-6 (IL-6), active matrix metalloproteinase-9 (MMP-9), tumor necrosis factor α (TNF-α), and hypersensitive C-reactive protein (hs-CRP) levels, were compared between a group who showed improvement (the improvement group) and a group who did not show improvement (the non-improvement group). Relevant factors for early neurological improvement after thrombolysis with alteplase were analyzed by using multivariate logistic regression models. A Pearson linear correlation analysis was also performed on blood glucose variation and inflammatory factor levels within the two groups. Results: A total of 146 patients were included, 63 of which had early symptom improvement (43.15%). The diabetes ratio, atrial fibrillation ratio, baseline NHISS score, random blood glucose at admission, and glycosylated hemoglobin of patients in the improvement group were significantly lower than those in the non-improvement group (P < 0.05 in all cases). The mean blood glucose, standard deviation of blood glucose, mean amplitude of glycemic excursion, and mean blood glucose variation coefficients of patients in the improvement group were significantly lower than those in the non-improvement group (P < 0.05). Serum inflammatory factor levels, including IL-6, MMP-9, TNF-α and hs-CRP, were significantly lower in patients in the improvement group compared to patients in the non-improvement group (P < 0.05). Multivariate logistic regression analysis showed that baseline NIHSS scores (OR = 1.28, 95% CI = 1.05-1.62, P = 0.02), glycosylated hemoglobin scores (OR = 2.57, 95% CI = 1.78-3.98, P = 0.0005), diabetes (OR = 13.10, 95% CI = 1.63~131.45, P = 0.021), the mean amplitude of glycemic excursion (OR = 2.98, 95% CI = 1.92-5.00, P < 0.0001), and the mean variation coefficient of blood glucose (OR = 1.40, 95% CI = 1.26-1.60, P = 0.0078) were significantly correlated with early symptom improvement after thrombolysis. Pearson linear correlation analysis showed that the standard deviation of blood glucose, mean amplitude of glycemic excursion, and the mean variation coefficient of blood glucose were significantly positively correlated with IL-6, MMP-9, TNF-α and hs-CRP levels (P < 0.01). Conclusions: Blood glucose variability is correlated with early neurological improvement after intravenous thrombolysis with alteplase in AIS patients. With the increase of blood glucose fluctuation range, the inflammatory response is enhanced, which affects the prognosis of patients.

4.
Lancet Reg Health West Pac ; 21: 100406, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35243459

ABSTRACT

BACKGROUND: In recent years, a series of initiatives have been launched to promote intravenous thrombolysis (IVT) and endovascular therapy (EVT) for acute ischaemic stroke (AIS) in China. We aimed to update the rates of IVT and EVT in China between 2019 and 2020 and to evaluate the current IVT and EVT according to hospital grades. METHODS: Cross-sectional data on patients receiving IVT/EVT were derived from the Bigdata Observatory platform for Stroke of China (BOSC). The monthly number of discharged patients with a principal diagnosis of AIS was derived from the first pages of medical records of each hospital. The rates and information of IVT and EVT were analysed according to hospital grades. FINDINGS: During this period, 938 tertiary hospitals and 786 secondary hospitals from 31 provinces continuously reported data to the BOSC. The overall IVT rate for AIS was 5·64%, and the EVT rate was 1·45%. The IVT rate in secondary hospitals was higher than that in tertiary hospitals (6·39% vs. 5·39%, P < 0·001), whereas the EVT rate in secondary hospitals was much lower than that in tertiary hospitals (0·29% vs. 1·84%, P < 0·001). Significant differences in demographic and clinical characteristics of patients receiving IVT/EVT were also shown between tertiary and secondary hospitals. INTERPRETATION: The rates of IVT and EVT for AIS have greatly increased in China, but there is still a large gap compared with developed countries. Hospital inhomogeneity in IVT and EVT suggests the importance of developing a region-specific network for stroke treatment. FUNDING: None.

6.
Front Cell Dev Biol ; 9: 777026, 2021.
Article in English | MEDLINE | ID: mdl-34869379

ABSTRACT

Multiple GLP-1-derived therapeutics are clinically used to treat type 2 diabetes and obesity. However, the underlying mechanism of how these drugs regulate the body weight of obese patients remains incompletely understood. Here, we report that the lipolysis effects of GLP-1 on ß cells can depend on its induced expression of fibronectin type III domain containing 5 (FNDC5). The transmembrane FNDC5 is a precursor of the recently identified hormone irisin that possesses a range of bioactivities, including anti-obesity and anti-diabetes. We revealed that GLP-1 upregulates the expression and secretion of FNDC5 in ß cells, while GLP-1 itself fails to activate the lipolysis genes in FNDC5-knockout ß cells. In addition, liraglutide, a clinically used GLP-1 receptor agonist, induced the expression of FNDC5 in mouse pancreas and brain tissues and increased the serum level of secreted FNDC5. Furthermore, we observed the expression of the well-known membrane-associated FNDC5 and a novel, secretable FNDC5 (sFNDC5) isoform in ß cells and multiple rat tissues. Recombinant sFNDC5 stimulated lipolysis of wild type and FNDC5-knockout ß cells. This new isoform further induced lipolysis and browning of adipocytes, and similar to irisin, executed potent anti-obesity activities in an obese mouse model. Overall, our studies provided new mechanistic insights into GLP-1's anti-obesity actions in which GLP-1 induces the secretion of FNDC5 derivatives from its responsive organs that then mediate its anti-obesity activities.

7.
Plant J ; 108(5): 1382-1399, 2021 12.
Article in English | MEDLINE | ID: mdl-34587334

ABSTRACT

Malvids is one of the largest clades of rosids, includes 58 families and exhibits remarkable morphological and ecological diversity. Here, we report a high-quality chromosome-level genome assembly for Euscaphis japonica, an early-diverging species within malvids. Genome-based phylogenetic analysis suggests that the unstable phylogenetic position of E. japonica may result from incomplete lineage sorting and hybridization event during the diversification of the ancestral population of malvids. Euscaphis japonica experienced two polyploidization events: the ancient whole genome triplication event shared with most eudicots (commonly known as the γ event) and a more recent whole genome duplication event, unique to E. japonica. By resequencing 101 samples from 11 populations, we speculate that the temperature has led to the differentiation of the evergreen and deciduous of E. japonica and the completely different population histories of these two groups. In total, 1012 candidate positively selected genes in the evergreen were detected, some of which are involved in flower and fruit development. We found that reddening and dehiscence of the E. japonica pericarp and long fruit-hanging time promoted the reproduction of E. japonica populations, and revealed the expression patterns of genes related to fruit reddening, dehiscence and abscission. The key genes involved in pentacyclic triterpene synthesis in E. japonica were identified, and different expression patterns of these genes may contribute to pentacyclic triterpene diversification. Our work sheds light on the evolution of E. japonica and malvids, particularly on the diversification of E. japonica and the genetic basis for their fruit dehiscence and abscission.


Subject(s)
Evolution, Molecular , Genome, Plant/genetics , Magnoliopsida/genetics , Fruit/genetics
8.
Neurotoxicology ; 87: 62-69, 2021 12.
Article in English | MEDLINE | ID: mdl-34481870

ABSTRACT

Parkinson's disease (PD) is a complicated multifactorial neurodegenerative disorder. Oxidative stress, neuroinflammatory response, and activation of apoptosis have been proposed to be tightly involved in the pathogenesis of PD. Genkwanin is a typical bioactive non-glycosylated flavonoid with anti-inflammatory and anti-oxidant activities. However, the effect of genkwanin on PD remains unclear. Cell viability, lactate dehydrogenase (LDH) release, caspase-3/7 activity, and apoptosis was evaluated by MTT, LDH release assay, caspase-3/7 activity assay, and TUNEL assay, respectively. The secretion of prostaglandin E2 (PGE2), tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and IL-6 were measured by respective commercial ELISA kits. The mRNA expression of TNF-α, IL-1ß, and IL-6 was detected by qRT-PCR. The protein levels of cycloxygenase-2 (COX-2), toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), and NOD-like receptor (NLR) protein: 3 (NLRP3) were determined by western blot analysis. Genkwanin at concentrations less than 40 µM had no impact on cell viability and LDH release. Genkwanin suppressed MPP+-induced neuroinflammation in SH-SY5Y cells. MPP+ treatment inhibited cell viability, increased LDH release, apoptosis, and ROS generation, and reduced superoxide dismutase (SOD) activity in SH-SY5Y cells, which were abolished by genkwanin treatment. Genkwanin suppressed MPP+-induced activation of TLR4/MyD88/NLRP3 inflammasome pathway in SH-SY5Y cells. TLR4 overexpression weakened the anti-inflammatory and anti-neurotoxicity of genkwanin in SH-SY5Y cells. In conclusion, genkwanin attenuated neuroinflammation and neurotoxicity by inhibiting TLR4/MyD88/NLRP3 inflammasome pathway in MPP+-induced cellular model of PD.


Subject(s)
1-Methyl-4-phenylpyridinium/toxicity , Flavones/pharmacology , Inflammasomes/drug effects , Myeloid Differentiation Factor 88/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Neuroprotective Agents/pharmacology , Parkinson Disease/drug therapy , Signal Transduction/drug effects , Toll-Like Receptor 4/metabolism , Apoptosis/drug effects , Blotting, Western , Cell Line , Humans , Neuroinflammatory Diseases/chemically induced , Neuroinflammatory Diseases/drug therapy , Oxidative Stress/drug effects , Real-Time Polymerase Chain Reaction
9.
J Med Chem ; 64(11): 7275-7295, 2021 06 10.
Article in English | MEDLINE | ID: mdl-33881312

ABSTRACT

Pathogenic bacteria demonstrate incredible abilities to evade conventional antibiotics through the development of resistance and formation of dormant, surface-attached biofilms. Therefore, agents that target and eradicate planktonic and biofilm bacteria are of significant interest. We explored a new series of halogenated phenazines (HP) through the use of N-aryl-2-nitrosoaniline synthetic intermediates that enabled functionalization of the 3-position of this scaffold. Several HPs demonstrated potent antibacterial and biofilm-killing activities (e.g., HP 29, against methicillin-resistant Staphylococcus aureus: MIC = 0.075 µM; MBEC = 2.35 µM), and transcriptional analysis revealed that HPs 3, 28, and 29 induce rapid iron starvation in MRSA biofilms. Several HPs demonstrated excellent activities against Mycobacterium tuberculosis (HP 34, MIC = 0.80 µM against CDC1551). This work established new SAR insights, and HP 29 demonstrated efficacy in dorsal wound infection models in mice. Encouraged by these findings, we believe that HPs could lead to significant advances in the treatment of challenging infections.


Subject(s)
Aniline Compounds/chemistry , Anti-Bacterial Agents/chemical synthesis , Phenazines/chemistry , Animals , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Biofilms/drug effects , Cell Line , Cell Survival/drug effects , Disease Models, Animal , Drug Design , Female , Halogenation , Humans , Iron/chemistry , Iron Deficiencies , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/physiology , Mice , Mice, Inbred BALB C , Mycobacterium tuberculosis/drug effects , Phenazines/pharmacology , Phenazines/therapeutic use , Staphylococcal Infections/drug therapy , Structure-Activity Relationship , Wound Healing/drug effects
10.
Folia Histochem Cytobiol ; 59(1): 57-65, 2021.
Article in English | MEDLINE | ID: mdl-33651374

ABSTRACT

INTRODUCTION: The pathological mechanism of cerebral ischemia/reperfusion (CIR) injury is complicated and unclear. Apart from the involvement of many low-molecular factors it was found that several miRNAs were dysregulated during and after CIR injury in cell models. This study aimed to explore the effects of miR-378a-5p on in vitro model of (CIR) injury-induced neuronal apoptosis and provide a new mechanism of CIR injury. MATERIAL AND METHODS: Primary hippocampal neurons were isolated from newborn Sprague-Dawley rats. Oxygen- glucose deprivation/reoxygenation (OGDR) for 24 h and 48 h was used as an in vitro model of CIR. Cell viability was measured using MTT assay and apoptosis was determined by flow cytometry. Quantitative real time PCR (qRT-PCR) assay and Western blotting were used to examine mRNA and protein expressions, respectively. TargetScan was used to predict the direct target of miR-378a-5p and luciferase assay was used to validate that calmodulin-dependent protein kinase kinase-2 (CAMKK2) was the direct target of miR-378a-5p. RESULTS: miR-378a-5p expression was significantly increased after OGDR at 24 h and 48 h. After OGDR, cell viability was reduced, which was reversed by miR-378a-5p and enhanced by shCAMKK2 plasmid. Cell apoptosis was increased after OGDR, which was prevented by miR-378a-5p and enhanced by shCAMKK2 plasmid. Results of TargetScan and luciferase assay demonstrated that miR-378a-5p could directly bind to 3'-untranslated region (3'-UTR) of CAMKK2. Both mRNA and protein expression of CAMKK2 were downregulated by miR-378a-5p mimics and upregulated by miR-378a-5p inhibitors. Phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) was positively associated with expression of CAMKK2. CONCLUSIONS: Data of this study indicated that miR-378a-5p was significantly overexpressed after OGDR. miR-378a-5p could bind to 3'-UTR of CAMKK2 to inhibit cell proliferation through regulation of CAMKK2/AMPK pathway providing a new mechanism and biomarker for the diagnosis and potential treatment of CIR injury.


Subject(s)
Apoptosis/physiology , MicroRNAs/metabolism , Neurons/metabolism , Reperfusion Injury/physiopathology , Signal Transduction/physiology , AMP-Activated Protein Kinases/metabolism , Animals , Animals, Newborn , Calcium-Calmodulin-Dependent Protein Kinase Kinase/metabolism , Cell Proliferation/physiology , Cell Survival/physiology , HEK293 Cells , Hippocampus/pathology , Humans , Rats, Sprague-Dawley
11.
Chembiochem ; 22(2): 416-422, 2021 01 15.
Article in English | MEDLINE | ID: mdl-32816319

ABSTRACT

Some fungal epithiodiketopiperazine alkaloids display α,ß-polysulfide bridges alongside diverse structural variations. However, the logic of their chemical diversity has rarely been explored. Here, we report the identification of three new (2, 3, 8) and five known (1, 4-7) epithiodiketopiperazines of this subtype from a marine-derived Penicillium sp. The structure elucidation was supported by multiple spectroscopic analyses. Importantly, we observed multiple nonenzymatic interconversions of these analogues in aqueous solutions and organic solvents. Furthermore, the same biosynthetic origin of these compounds was supported by one mined gene cluster. The dominant analogue (1) demonstrated selective cytotoxicity to androgen-sensitive prostate cancer cells and HIF-depleted colorectal cells and mild antiaging activities, linking the bioactivity to oxidative stress. These results provide crucial insight into the formation of fungal epithiodiketopiperazines through chemical interconversions.


Subject(s)
Diketopiperazines/chemistry , Penicillium/chemistry , Sulfides/chemistry , Molecular Structure
12.
ACS Chem Biol ; 15(8): 2281-2288, 2020 08 21.
Article in English | MEDLINE | ID: mdl-32786290

ABSTRACT

Microbes are essential to the global ecosystem, but undesirable microbial growth causes issues ranging from food spoilage and infectious diseases to harmful cyanobacterial blooms. The use of chemicals to control microbial growth has achieved significant success, while specific roles for a majority of essential genes in growth control remain unexplored. Here, we show the growth inhibition of cyanobacterial species by targeting an essential enzyme for the biosynthesis of branched-chain amino acids. Specifically, we report the biochemical, genetic, and structural characterization of dihydroxyacid dehydratase from the model cyanobacterium Synechocystis sp. PCC 6803 (SnDHAD). Our studies suggest that SnDHAD is an oxygen-stable enzyme containing a [2Fe-2S] cluster. Furthermore, we demonstrate that SnDHAD is selectively inhibited in vitro and in vivo by the natural product aspterric acid, which also inhibits the growth of representative bloom-forming Microcystis and Anabaena strains but has minimal effects on microbial pathogens with [4Fe-4S] containing DHADs. This study suggests DHADs as a promising target for the precise growth control of microbes and highlights the exploration of other untargeted essential genes for microbial management.


Subject(s)
Hydro-Lyases/metabolism , Synechocystis/enzymology , Synechocystis/growth & development , Catalytic Domain , Escherichia coli/genetics , Escherichia coli/growth & development , Iron-Sulfur Proteins/metabolism , Mutation , Oxygen/metabolism
13.
Medchemcomm ; 10(5): 712-716, 2019 May 01.
Article in English | MEDLINE | ID: mdl-31191861

ABSTRACT

While a number of disinfection techniques are employed in healthcare units, the eradication of drug-resistant microorganisms remains a challenge. We recently reported N-arylated NH125 analogue 1, which demonstrated potent biofilm eradication and antibacterial activities against a panel of drug-resistant pathogens. The broad-spectrum activities observed for 1 along with its rapid eradication of MRSA persister cells suggested that this agent, and related analogues, can serve as disinfectants for antibiotic resistant pathogens in healthcare settings. Here, we report the rapid bactericidal activities of 1 against a panel of exponentially-growing, drug-resistant pathogens. Against MRSA, MRSE, VRE and MDR A. baumannii, 1 eradicated bacterial cells after five minutes when tested at 50 µM (3- to 6-log reduction of CFU per mL). We highlighted the rapid killing activities by demonstrating that 1 eradicates 99.99% of viable MRSA 1707 cells in one minute (50 µM, 4-log reduction of CFU per mL). In addition, 1 rapidly eradicated fungal pathogen C. neoformans in kill kinetic experiments. A solution of 1 demonstrated similar shelf stability to known disinfectant BAC-16 when tested up to 111 days after being stored. Collectively, our data highlights the potential of 1 to be used as a disinfecting agent to prevent healthcare-associated, drug-resistant infections.

14.
Appl Environ Microbiol ; 84(11)2018 06 01.
Article in English | MEDLINE | ID: mdl-29602787

ABSTRACT

Thaxtomins are virulence factors of most plant-pathogenic Streptomyces strains. Due to their potent herbicidal activity, attractive environmental compatibility, and inherent biodegradability, thaxtomins are key active ingredients of bioherbicides approved by the U.S. Environmental Protection Agency. However, the low yield of thaxtomins in native Streptomyces producers limits their wide agricultural applications. Here, we describe the high-yield production of thaxtomins in a heterologous host. The thaxtomin gene cluster from S. scabiei 87.22 was cloned and expressed in S. albus J1074 after chromosomal integration. The production of thaxtomins and nitrotryptophan analogs was observed using liquid chromatography-mass spectrometry (LC-MS) analysis. When the engineered S. albus J1074 was cultured in the minimal medium Thx defined medium supplemented with 1% cellobiose (TDMc), the yield of the most abundant and herbicidal analog, thaxtomin A, was 10 times higher than that in S. scabiei 87.22, and optimization of the medium resulted in the highest yield of thaxtomin analogs at about 222 mg/liter. Further engineering of the thaxtomin biosynthetic gene cluster through gene deletion led to the production of multiple biosynthetic intermediates important to the chemical synthesis of new analogs. Additionally, the versatility of the thaxtomin biosynthetic system in S. albus J1074 was capitalized on to produce one unnatural fluorinated analog, 5-fluoro-thaxtomin A (5-F-thaxtomin A), whose structure was elucidated by a combination of MS and one-dimensional (1D) and 2D nuclear magnetic resonance (NMR) analyses. Natural and unnatural thaxtomins demonstrated potent herbicidal activity in radish seedling assays. These results indicated that S. albus J1074 has the potential to produce thaxtomins and analogs thereof with high yield, fostering their agricultural applications.IMPORTANCE Thaxtomins are agriculturally valuable herbicidal natural products, but the productivity of native producers is limiting. Heterologous expression of the thaxtomin gene cluster in S. albus J1074 resulted in the highest yield of thaxtomins ever reported, representing a significant leap forward in its wide agricultural use. Furthermore, current synthetic routes to thaxtomins and analogs are lengthy, and two thaxtomin biosynthetic intermediates produced at high yields in this work can provide precursors and building blocks to advanced synthetic routes. Importantly, the production of 5-F-thaxtomin A in engineered S. albus J1074 demonstrated a viable alternative to chemical methods in the synthesis of new thaxtomin analogs. Moreover, our work presents an attractive synthetic biology strategy to improve the supply of herbicidal thaxtomins, likely finding general applications in the discovery and production of many other bioactive natural products.


Subject(s)
Herbicides/metabolism , Indoles/metabolism , Multigene Family , Piperazines/metabolism , Streptomyces/metabolism , Synthetic Biology/methods , Gene Expression Regulation, Bacterial , Streptomyces/genetics , Virulence Factors/metabolism
15.
Exp Ther Med ; 15(1): 127-130, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29375679

ABSTRACT

The aim of the study was to investigate the efficacy of homemade tolcapone in treatment of patients with Parkinson's disease (PD). Eighty patients with PD were subjected to randomized, double-blind, placebo-controlled and parallel-group study. PD patients were randomly divided into the tolcapone treatment group (41 cases) and placebo group (39 cases). Each patient received 1 pill of tolcapone or placebo, 3 times per day for 26 weeks. Efficacy was evaluated using the internationally used unified Parkinson's disease rating scale (UPDRS) scoring system for PD symptoms. After the treatment for 26 weeks, the cognitive function, tremor, muscle stiffness, voluntary movement and autonomic nerve symptoms were compared between the two groups using UPDRS scores. Compared with the placebo group, cognitive function, muscle stiffness and voluntary movement reduction were significantly improved in patients of the tolcapone group (P<0.05). However, no significant differences in UPDRS scores of autonomic nerve symptoms and tremor were found between two groups after treatment (P>0.05). Tolcapone, a catechol-O-methyl transferase (COMT) inhibitor, can improve the motor function of patients with PD, especially exercise and muscle stiffness. Tolcapone can also improve the cognitive function of patients.

16.
J Med Genet ; 55(2): 73-80, 2018 02.
Article in English | MEDLINE | ID: mdl-29151060

ABSTRACT

Parkinson's disease (PD) is a complex and heterogeneous neurological condition characterised mainly by bradykinesia, resting tremor, rigidity and postural instability, symptoms that together comprise the parkinsonian syndrome. Non-motor symptoms preceding and following clinical onset are also helpful diagnostic markers revealing a widespread and progressive pathology. Many other neurological conditions also include parkinsonism as primary or secondary symptom, confounding their diagnosis and treatment. Although overall disease course and end-stage pathological examination single out these conditions, the significant overlaps suggest that they are part of a continuous disease spectrum. Recent genetic discoveries support this idea because mutations in a few genes (α-synuclein, LRRK2, tau) can cause partially overlapping pathologies. Additionally, mutations in causative genes and environmental toxins identify protein homeostasis and the mitochondria as key mediators of degeneration of dopaminergic circuits in the basal ganglia. The evolving mechanistic insight into the pathophysiology of PD and related conditions will contribute to the development of targeted and effective symptomatic treatments into disease-modifying therapies that will reduce the burden of these dreadful conditions.


Subject(s)
Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/genetics , Mutation , Parkinson Disease/genetics , Parkinsonian Disorders/etiology , Dopamine/metabolism , Genes, Dominant , Humans , Mitochondria/metabolism , Mitochondria/pathology , Neurons/metabolism , Neurons/pathology , Parkinson Disease/etiology , Parkinsonian Disorders/chemically induced , Parkinsonian Disorders/pathology , alpha-Synuclein/genetics , tau Proteins/genetics , tau Proteins/metabolism
17.
Proc Natl Acad Sci U S A ; 114(34): 8980-8985, 2017 08 22.
Article in English | MEDLINE | ID: mdl-28784797

ABSTRACT

Glycans possess significant chemical diversity; glycan binding proteins (GBPs) recognize specific glycans to translate their structures to functions in various physiological and pathological processes. Therefore, the discovery and characterization of novel GBPs and characterization of glycan-GBP interactions are significant to provide potential targets for therapeutic intervention of many diseases. Here, we report the biochemical, functional, and structural characterization of a 130-amino-acid protein, Y3, from the mushroom Coprinus comatus Biochemical studies of recombinant Y3 from a yeast expression system demonstrated the protein is a unique GBP. Additionally, we show that Y3 exhibits selective and potent cytotoxicity toward human T-cell leukemia Jurkat cells compared with a panel of cancer cell lines via inducing caspase-dependent apoptosis. Screening of a glycan array demonstrated GalNAcß1-4(Fucα1-3)GlcNAc (LDNF) as a specific Y3-binding ligand. To provide a structural basis for function, the crystal structure was solved to a resolution of 1.2 Å, revealing a single-domain αßα-sandwich motif. Two monomers were dimerized to form a large 10-stranded, antiparallel ß-sheet flanked by α-helices on each side, representing a unique oligomerization mode among GBPs. A large glycan binding pocket extends into the dimeric interface, and docking of LDNF identified key residues for glycan interactions. Disruption of residues predicted to be involved in LDNF/Y3 interactions resulted in the significant loss of binding to Jurkat T-cells and severely impaired their cytotoxicity. Collectively, these results demonstrate Y3 to be a GBP with selective cytotoxicity toward human T-cell leukemia cells and indicate its potential use in cancer diagnosis and treatment.


Subject(s)
Agaricales/metabolism , Coprinus/metabolism , Fungal Proteins/metabolism , Polysaccharides/metabolism , Amino Acid Sequence , Apoptosis/drug effects , Cell Survival/drug effects , Crystallography, X-Ray , Fungal Proteins/chemistry , Fungal Proteins/pharmacology , HEK293 Cells , Humans , Jurkat Cells , Models, Molecular , Protein Binding , Protein Conformation , Protein Multimerization , Sequence Homology, Amino Acid
18.
Int J Nanomedicine ; 11: 4535-4544, 2016.
Article in English | MEDLINE | ID: mdl-27660445

ABSTRACT

Nanoparticles have promising applications in drug delivery for cancer therapy. Herein, we prepared cationic 1,2-dioleoyl-3-trimethylammonium propane/methoxypoly (ethyleneglycol) (DPP) nanoparticles to deliver doxorubicin (Dox) for intravesical therapy of bladder cancer. The DPP micelles have a mean dynamic diameter of 18.65 nm and a mean zeta potential of +19.6 mV. The DPP micelles could prolong the residence of Dox in the bladder, enhance the penetration of Dox into the bladder wall, and improve cellular uptake of Dox. The encapsulation by DPP micelles significantly improved the anticancer effect of Dox against orthotopic bladder cancer in vivo. This work described a Dox-loaded DPP nanoparticle with potential applications in intravesical therapy of bladder cancer.

19.
Int J Nanomedicine ; 11: 4545-4552, 2016.
Article in English | MEDLINE | ID: mdl-27660446

ABSTRACT

Cancer chemotherapy can benefit from the combination of different anticancer drugs. Here, we prepared doxorubicin (Dox)- and thioridazine (Thio)-coloaded methoxy poly(ethylene glycol)-poly(l-lactic acid) (MPEG-PLA) nanoparticles (NPs) for breast cancer therapy. These NPs have an average particle size of 27 nm. The drug loading efficiencies of Thio and Dox are 4.71% and 1.98%, respectively. Compared to the treatment of Thio or Dox alone, the combination of Thio and Dox exhibited a synergistic effect in inhibiting the growth of 4T1 breast cancer cells in vitro. In addition, the Thio- and Dox-coloaded MPEG-PLA NPs could efficiently suppress the growth of breast cancer cells in vivo. This study suggests that Thio- and Dox-coloaded MPEG-PLA NPs might have potential applications in breast cancer treatment.

20.
Int J Antimicrob Agents ; 48(2): 208-11, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27256584

ABSTRACT

With the increasing prevalence of fungal infections coupled with emerging drug resistance, there is an urgent need for new and effective antifungal agents. Here we report the antifungal activities of 19 diverse halogenated quinoline (HQ) small molecules against Candida albicans and Cryptococcus neoformans. Four HQ analogues inhibited C. albicans growth with a minimum inhibitory concentration (MIC) of 100 nM, whilst 16 analogues effectively inhibited C. neoformans at MICs of 50-780 nM. Remarkably, two HQ analogues eradicated mature C. albicans and C. neoformans biofilms [minimum biofilm eradication concentration (MBEC) = 6.25-62.5 µM]. Several active HQs were found to penetrate into fungal cells, whilst one inactive analogue was unable to, suggesting that HQs elicit their antifungal activities through an intracellular mode of action. HQs are a promising class of small molecules that may be useful in future antifungal treatments.


Subject(s)
Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Biofilms/drug effects , Candida albicans/drug effects , Cryptococcus neoformans/drug effects , Quinolines/chemistry , Quinolines/pharmacology , Candida albicans/physiology , Cryptococcus neoformans/physiology , Halogenation , Humans , Microbial Sensitivity Tests
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