Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 53
Filter
Add more filters










Publication year range
1.
Phytomedicine ; 130: 155763, 2024 Jul 25.
Article in English | MEDLINE | ID: mdl-38820661

ABSTRACT

BACKGROUND: Emodin is a chemical compound found in traditional Chinese herbs. It possesses anti-inflammatory and many other pharmacological effects. Our previous study showed that emodin significantly alleviates the inflammation effect of severe acute pancreatitis (SAP). However, its poor solubility, high toxicity and limited pancreas retention time hinder its clinical application. PURPOSE: We aimed to prepare emodin nanocapsules with improved bioavailability to achieve the controlled release of emodin by targeting macrophages. Further, the mechanism of mannose-conjugated chitosan-coated lipid nanocapsules loaded with emodin (M-CS-E-LNC) in the treatment of SAP was explored. METHODS: M-CS-E-LNC were prepared by the phase inversion method with slight modification. The expression of inflammation mediators and the anti-inflammation efficacy of M-CS-E-LNC were examined by ELISA, IHC and IF in macrophage cells and LPS-induced SAP mice. IVIS spectrum imaging and HPLC were applied to explore the controlled release of M-CS-E-LNC in the pancreas. LC-MS/MS was performed for lipidomics analysis of macrophages. Moreover, a vector-based short hairpin RNA (shRNA) method was used to silence CTP1 gene expression in macrophage cells. RESULTS: The levels of inflammatory mediators in macrophages were markedly decreased after treatment with M-CS-E-LNC. The same anti-inflammation effects were detected in SAP mouse through the analysis of serum levels of amylase, TNF-α and IL-6. Importantly, M-CS-E-LNC allowed the emodin to selectively accumulate at pancreas and gastrointestinal tissues, thus exhibiting a targeted release. Mechanistically, the M-CS-E-LNC treatment group showed up-regulated expression of the carnitine palmitoyltransferase 1 (CPT1) protein which promoted intracellular long-chain fatty acid transport, thereby promoting the M2 phenotype polarization of macrophages. CONCLUSION: M-CS-E-LNC exhibited significantly improved bioavailability and water solubility, which translated to greater therapeutic effects on macrophage polarization. Our findings also demonstrate, for the first time, that CPT1 may be a new therapeutic target for SAP treatment.


Subject(s)
Emodin , Lipid Metabolism , Macrophages , Nanocapsules , Pancreatitis , Animals , Emodin/pharmacology , Mice , Macrophages/drug effects , Macrophages/metabolism , Pancreatitis/drug therapy , RAW 264.7 Cells , Lipid Metabolism/drug effects , Male , Anti-Inflammatory Agents/pharmacology , Chitosan/pharmacology , Chitosan/chemistry , Mice, Inbred C57BL , Lipopolysaccharides , Metabolic Reprogramming
2.
J Nat Prod ; 86(8): 1885-1890, 2023 08 25.
Article in English | MEDLINE | ID: mdl-37550948

ABSTRACT

Three new cyclic peptides, meristosporins A, B, and C (1-3), one of which features an unusual amino acid, were isolated from the opportunistic pathogen Basidiobolus meristosporus and identified by 1D, 2D NMR, MS/MS, and Marfey's analysis. The biosynthetic pathway of the hexapeptide meristosporin A (1) was deduced based on nonribosomal peptide synthetase gene clusters analysis. Compounds 1 and 2 showed cytotoxicity to RAW264.7 and 293T cells, respectively. These compounds may be involved in the fungal injury caused to human cells.


Subject(s)
Peptides, Cyclic , Tandem Mass Spectrometry , Humans , Peptides, Cyclic/chemistry , Amino Acids , Magnetic Resonance Spectroscopy , Molecular Structure
3.
PLoS Pathog ; 19(5): e1011397, 2023 05.
Article in English | MEDLINE | ID: mdl-37216409

ABSTRACT

Mycoviruses are widely present in all major groups of fungi but those in entomopathogenic Metarhizium spp. remain understudied. In this investigation, a novel double-stranded (ds) RNA virus is isolated from Metarhizium majus and named Metarhizium majus partitivirus 1 (MmPV1). The complete genome sequence of MmPV1 comprises two monocistronic dsRNA segments (dsRNA 1 and dsRNA 2), which encode an RNA-dependent RNA polymerase (RdRp) and a capsid protein (CP), respectively. MmPV1 is classified as a new member of the genus Gammapartitivirus in the family Partitiviridae based on phylogenetic analysis. As compared to an MmPV1-free strain, two isogenic MmPV1-infected single-spore isolates were compromised in terms of conidiation, and tolerance to heat shock and UV-B irradiation, while these phenotypes were accompanied by transcriptional suppression of multiple genes involved in conidiation, heat shock response and DNA damage repair. MmPV1 attenuated fungal virulence since infection resulted in reduced conidiation, hydrophobicity, adhesion, and cuticular penetration. Additionally, secondary metabolites were significantly altered by MmPV1 infection, including reduced production of triterpenoids, and metarhizins A and B, and increased production of nitrogen and phosphorus compounds. However, expression of individual MmPV1 proteins in M. majus had no impact on the host phenotype, suggesting insubstantive links between defective phenotypes and a single viral protein. These findings indicate that MmPV1 infection decreases M. majus fitness to its environment and its insect-pathogenic lifestyle and environment through the orchestration of the host conidiation, stress tolerance, pathogenicity, and secondary metabolism.


Subject(s)
Metarhizium , RNA Viruses , Virulence , Metarhizium/genetics , Secondary Metabolism , Phylogeny , RNA Viruses/genetics , Spores, Fungal/genetics
4.
Phytochemistry ; 209: 113636, 2023 May.
Article in English | MEDLINE | ID: mdl-36871901

ABSTRACT

Basidiobolus meristosporus is an opportunistic pathogen of mammals with unique habitats, but its metabolites have not been extensively studied. Through semi-preparative HPLC, nine undescribed cyclic pentapeptides were isolated from mycelia of B. meristosporus RCEF4516. The structure of the compounds 1-9 were identified with MS/MS and NMR data and designated as basidiosin D-L respectively. The absolute configurations were determined according to the advanced Marfey's method after compound hydrolysis. Bioactivity testing showed that compounds 1, 2, 3, 4 and 8 decreased NO production in LPS-activated RAW264.7 cells in a concentration-dependent manner. The nine compounds showed cytotoxicity against RAW264.7, 293 T and HepG2 cells. All the compounds except compound 7 showed stronger inhibitory effects on α-glucosidase than acarbose.


Subject(s)
Antineoplastic Agents , alpha-Glucosidases , Animals , Tandem Mass Spectrometry , Acarbose , Anti-Inflammatory Agents/pharmacology , Mammals
5.
Food Chem ; 407: 135172, 2023 May 01.
Article in English | MEDLINE | ID: mdl-36508871

ABSTRACT

Cordyceps militaris (C. militaris) has been approved and widely used in healthy food. The present study aimed to improve the flavor of summer Keemun black tea (KBT) using C. militaris solid-state fermentation. Combined with sensory evaluation, the volatile and non-volatile components of solid-state fermentation of KBT (SSF-KBT) and KBT were analyzed. The results showed that after the solid-state fermentation, the contents of total polyphenol, total flavonoid, and total free amino acids were significantly reduced. Further non-targeted metabolomics analysis revealed that the contents of non-galloylated catechins and d-mannitol increased, while the galloylated catechins and flavonoid glycosides decreased as did the bitterness and astringency of KBT. Dihydro-ß-ionone and ß-ionone (OAV = 59321.97 and 8154.17) were the aroma-active compounds imparting woody and floral odors in SSF-KBT, respectively. Current study provides a new avenue to develop summer-autumn KBT.


Subject(s)
Camellia sinensis , Catechin , Cordyceps , Tea/chemistry , Fermentation , Camellia sinensis/chemistry , Flavonoids , Catechin/analysis , Metabolomics
6.
Food Funct ; 13(18): 9299-9310, 2022 Sep 22.
Article in English | MEDLINE | ID: mdl-35968754

ABSTRACT

Green tea polyphenols show positive effects on human health and longevity. However, knowledge of the antiaging properties of green tea is limited to the major catechin epigallocatechin gallate (EGCG). The search for new ingredients in tea with strong antiaging activity deserves further study. Here we isolated and identified two new catechins from Zijuan green tea, named zijuanin E (1) and zijuanin F (2). Their structures were identified by extensive high-resolution mass spectroscopy (HR-MS), nuclear magnetic resonance (NMR), ultraviolet-vis (UV), infrared (IR) and circular dichroism (CD) spectroscopic analyses, and their 13C NMR and CD data were calculated. We used the nematode Caenorhabditis elegans (C. elegans) to analyze the health benefits and longevity effects of 1 and 2. Compounds 1 and 2 (100 µM) remarkably prolonged the lifespan of C. elegans by 67.2% and 56.0%, respectively, delaying the age-related decline of phenotypes, enhancing stress resistance, and reducing ROS and lipid accumulation. Furthermore, 1 and 2 did not affect the lifespan of daf-16, daf-2, sir-2.1, and skn-1 mutant worms, suggesting that they might work via the insulin/IGF and SKN-1/Nrf2 signaling pathways. Meanwhile, 1 and 2 also exhibited strong antioxidant activity in vitro. Surface plasmon resonance (SPR) evidence suggests that zijuanins E and F have strong human serum albumin (HSA) binding ability. Together, zijuanins E and F represent a new valuable class of tea components that promote healthspan and could be developed as potential dietary therapies against aging.


Subject(s)
Caenorhabditis elegans Proteins , Catechin , Animals , Antioxidants/pharmacology , Caenorhabditis elegans , Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans Proteins/metabolism , Catechin/chemistry , Insulin/metabolism , Lipids/pharmacology , Longevity , NF-E2-Related Factor 2/metabolism , Oxidative Stress , Reactive Oxygen Species/metabolism , Serum Albumin, Human/metabolism , Signal Transduction , Tea/chemistry
7.
J Fungi (Basel) ; 8(5)2022 May 06.
Article in English | MEDLINE | ID: mdl-35628740

ABSTRACT

Cordyceps chanhua is an important cordycipitoid mushroom widely used in Asia and beyond. Beauvericin (BEA), one of the bioactive compounds of C. chanhua, has attracted much attention because of its medicinal value and food safety risk. In order to clear up the relationship between oxidative stress and BEA synthesis, we investigated the impact of H2O2-induced oxidative stress on the secondary metabolism of C. chanhua using untargeted metabolomics and a transcript profiling approach. Metabolic profiling of C. chanhua mycelia found that in total, 73 differential metabolites were identified, including organic acids, phospholipids, and non-ribosomal peptides (NRPs), especially the content of BEA, increasing 13-fold under oxidative stress treatment. Combining transcriptomic and metabolomic analyses, we found that the genes and metabolites associated with the NRP metabolism, especially the BEA biosynthesis, were highly significantly enriched under H2O2-induced stress, which indicated that the BEA metabolism might be positive in the resistance of C. chanhua to oxidative stress. These results not only aid in better understanding of the resistance mechanisms of C. chanhua against oxidative stress but also might be helpful for molecular breeding of C. chanhua with low BEA content.

8.
AMB Express ; 12(1): 40, 2022 Apr 02.
Article in English | MEDLINE | ID: mdl-35366116

ABSTRACT

High-resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR) analysis revealed that there are 20 main components in spores and mycelia extract of Cordyceps fumosorosea strain RCEF 6672 including mannitol (1), uridine (2), adenine (3). N6-(2-hydroxyethyl)-adenosine (4). N6-(2-hydroxyethylacetate)-adenosine (5), fumosoroseanoside A (6) and B (7), ovalicin-4α-alcohol (8), 1-linoleoyl-sn-glycero-3-phosphocholine (9) and its isomer (10), fumosoroseain A (11) and its isomer (12), 5 non-ribosomal peptides (13 to 17) and 3 fatty acids (18 to 20). The compounds 5, 6, 7, 9 and 11 were prepared with preparative and semi-preparative HPLC and identified with 1D and 2D NMR. Compounds 4 and 5 were the first time identified from C. fumosorosea. Compounds 6, 7 and 11 are novel compounds. Compounds 6 and 7 showed antibacterial and antifungal activities, and 11 showed antiaging activity. All the secondary metabolites (4 to 8 and 11 to 17) have strong bioactivities indicating that the metabolites have pharmaceutical development potentiality.

9.
Front Pharmacol ; 12: 590994, 2021.
Article in English | MEDLINE | ID: mdl-33995005

ABSTRACT

Background: Qing-Yi Decoction (QYD) is a classic precompounded prescription with satisfactory clinical efficacy on acute pancreatitis (AP). However, the chemical profile and overall molecular mechanism of QYD in treating AP have not been clarified. Methods: In the present study, a rapid, simple, sensitive and reliable ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS)-based chemical profile was first established. An integration strategy of network pharmacology analysis and molecular docking based identified ingredients was further performed to screen out the potential targets and pathways involved in the treatment of QYD on AP. Finally, SD rats with acute pancreatitis were constructed to verify the predicted results through a western blot experiment. Results: A total of 110 compounds, including flavonoids, phenolic acids, alkaloids, monoterpenes, iridoids, triterpenes, phenylethanoid glycosides, anthraquinones and other miscellaneous compounds were identified, respectively. Eleven important components, 47 key targets and 15 related pathways based on network pharmacology analysis were obtained. Molecular docking simulation indicated that ERK1/2, c-Fos and p65 might play an essential role in QYD against AP. Finally, the western blot experiments showed that QYD could up-regulate the expression level of ERK1/2 and c-Fos, while down-regulate the expression level of p65. Conclusion: This study predicted and validated that QYD may treat AP by inhibiting inflammation and promoting apoptosis, which provides directions for further experimental studies.

10.
J Agric Food Chem ; 69(16): 4827-4839, 2021 Apr 28.
Article in English | MEDLINE | ID: mdl-33848156

ABSTRACT

Tea is an important beverage source of dietary polyphenols and well known for containing phenolic structure diversity. A series of phenylpropanoid-substituted catechins, flavonols, flavan-3-hexoside, and proanthocyanidin are present in different herbs with various biological activities, inspiring our exploration of phenylpropanoid-substituted ester type of catechins (PSECs) due to the enrichment of galloylated catechins in tea. In this study, we used a guiding-screening-location-isolation integrated route including creating a hypothesized PSEC dataset, MS/MS data acquiring, construction of molecular networks, and traditional column chromatography and preliminarily identified 14 PSECs by MS/MS spectrum. Two of these PSECs were further purified and elucidated by NMR and CD spectra. Further MS detection in tea products and fresh leaves suggests that the production of the two new compounds was enhanced during tea processing. The synthesis mechanism was proposed to obtain these types of components for further investigation on their roles in human health protection. This study provides an example for the exploration of new functional ingredients from food sources guided by MS/MS data-based networking, and also new insights into the reaction mechanism to form new catechin conjugates among polyphenols in green tea.


Subject(s)
Camellia sinensis , Catechin , Esters , Humans , Polyphenols/analysis , Tandem Mass Spectrometry , Tea
11.
Wideochir Inne Tech Maloinwazyjne ; 16(1): 19-29, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33786113

ABSTRACT

Endoscopic retrograde cholangiopancreatography (ERCP) is the main diagnosis and treatment for biliary and pancreatic diseases; however, ERCP requires a high level of technical skill and experience, and there is always a risk of complications. ERCP-related duodenal perforation is one of the most serious complications of ERCP, and although the incidence rate is relatively low, the mortality rate is high. Recently, the introduction of new classification methods and the development of endoscopic technology and equipment have made endoscopic therapy a new trend. This may change the management strategy of perforation. Therefore, we reviewed the latest developments in endoscopic management, surgical management, and conservative internal medicine management. In addition to introducing many new endoscope treatment methods, we also discussed the timing of interventions, the progress of endoscope and surgical indications, and corresponding prevention strategies. We aim to retrospectively analyse these treatment modalities to propose appropriate solutions to improve dynamic clinical therapy.

12.
Acta Biomater ; 124: 336-347, 2021 04 01.
Article in English | MEDLINE | ID: mdl-33578055

ABSTRACT

Extracellular vesicles (EVs) are membrane-encapsulated particles with critical biomedical functions, including mediating intercellular communication, assisting tumor metastasis, and carrying protein and microRNA biomarkers. The downstream applications of EVs are greatly influenced by the quality of the isolated EVs. However, almost none of the separation methods can simultaneously achieve both high yield and high purity of the isolated EVs, thus making the isolation of EVs an essential challenge in EV research. Here, we developed a magnetic bead-mediated selective adsorption strategy (MagExo) for easy-to-operate EV isolation. Benefited from the presence of an adsorption window between EVs and proteins under the effect of a hydrophilic polymer, EVs tend to adsorb on the surface of magnetic beads selectively and can be separated from biological fluids with high purity by simple magnetic separation. The proposed method was used for EV isolation from plasma and cell culture media (CCM), with two times higher yield and comparable purity of the harvested EVs to that obtained by ultracentrifugation (UC). Downstream applications in proteomics analysis showed 86.6% (plasma) and 86.5% (CCM) of the analyzed proteins were matched with the ExoCarta database, which indicates MagExo indeed enriches EVs efficiently. Furthermore, we found the target RNA amount of the isolated EVs by MagExo were almost dozens and hundred times higher than the gold standard DG-UC and ultracentrifugation (UC) methods, respectively. All the results show that MagExo is a reliable, easy, and efficient approach to harvest EVs for a wide variety of downstream applications with minimized sample usage. STATEMENT OF SIGNIFICANCE: Extracellular vesicles (EVs) are presently attracting increasing interest among clinical and scientific researchers. Although the downstream applications of EVs are recognized to be greatly affected by the quality of the isolated EVs, almost none of the separation methods can simultaneously achieve high yield and high purity of the isolated EVs; this makes the isolation of EVs an essential challenge in EV research. In the present work, we proposed a simple and easy-to-operate method (MagExo) for the separation and purification of EVs based on the phenomenon that EVs can be selectively adsorbed on the surface of magnetic microspheres in the presence of a hydrophilic polymer. The performance of MagExo was comparable to or even better than that of gold standard methods and commercial kits, with two times higher yield and comparable purity of the harvested EVs to that achieved with ultracentrifugation (UC); this could meet the requirements of various EV-associated downstream applications. In addition, MagExo can be easily automated by commercial liquid workstations, thus significantly improving the isolation throughput and paving a new way in clinical diagnosis and treatment.


Subject(s)
Extracellular Vesicles , MicroRNAs , Adsorption , Magnetic Phenomena , Ultracentrifugation
13.
Am J Cancer Res ; 10(11): 3551-3564, 2020.
Article in English | MEDLINE | ID: mdl-33294254

ABSTRACT

Increasing evidence highlights the role of the interleukin (IL)-17 family in pancreatic diseases. IL-17A induces acinar cell injury directly, recruits neutrophils, and cooperates with other inflammatory factors to exacerbate pancreatic inflammation. It also triggers islet ß-cell apoptosis and nitric oxide-dependent cytotoxicity, thus aggravating islet inflammation. IL-17A seems to have different roles in pancreatic intraepithelial neoplasia (PanIN) and pancreatic cancer (PC). IL-17A participates in the progression of acinar-ductal metaplasia (ADM) and PanIN, but not related to the characteristics of PC stem cells and the overall survival of patients. Acting similar to IL-17A, IL-17B accelerates the invasion and metastasis of PC, and predicts prognosis of PC and the therapeutic effect of gemcitabine. Herein, we review the current understanding of the pathogenesis of IL-17 in pancreatitis, type 1 diabetes mellitus (T1DM), and PC, as well as potential pharmacotherapy targeting IL-17 and its receptors in pancreatic diseases. The findings summarized in this article are of considerable significance for understanding the essential role of IL-17 in pancreatic diseases.

14.
Am J Transl Res ; 12(9): 5551-5562, 2020.
Article in English | MEDLINE | ID: mdl-33042437

ABSTRACT

Severe acute pancreatitis (SAP) is a serious abdominal disease associated with increased morbidity and high mortality rates. The initial pancreatic injury and inflammatory response, which begins within acinar cells, play vital roles in promoting SAP severity. Previous studies have indicated that overactivated autophagy in acinar cells increases the risk of SAP. Autophagy is affected by various signaling pathways, partially through long noncoding RNA (lncRNA)-PVT1. However, few studies have focused on the effect of lncRNA on autophagy in pancreatitis. Our results demonstrate that sodium taurocholate (STC) induces abnormal activation of the autophagic response in pancreatic acinar cells in vitro and in vivo. The lncRNA-PVT1 level was significantly upregulated in this process and was capable of targeting the miR-30a-5p/Beclin-1-mediated autophagy signaling pathway. Additionally, STC-induced pancreatic acinar cells injury and autophagy activation were all abrogated with the downregulation of lncRNA-PVT1 by shRNAs in vitro. Furthermore, we confirmed that the lncRNA-PVT1/miR-30a-5p/Beclin-1 axis induces abnormal autophagy in the pancreas of SAP rats. Collectively, these results demonstrate that the lncRNA-PVT1/miR-30a-5p/Beclin-1 axis is a potential target for improving SAP, thus providing a foundation for further development of therapeutics in the future.

15.
Biomed Pharmacother ; 131: 110693, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32882586

ABSTRACT

Macrophages play a crucial role in the pathogenesis of pancreatitis that is a common gastrointestinal disease. Particularly, macrophages differentiate into different phenotypes and exert diverse functions in acute pancreatitis (AP) and chronic pancreatitis (CP), respectively. In AP, macrophages in the pancreas and other related organs are mainly activated and differentiated into a pro-inflammatory M1 phenotype, and furthermore secrete inflammatory cytokines and mediators, causing local inflammation of the pancreas, and even intractable systemic inflammatory response or multiple organ failure. In CP, macrophages often exhibit a M2 polarisation and interact with pancreatic stellate cells (PSCs) in an autocrine and paracrine cytokine-dependent manner to promote the progression of pancreatic fibrosis. As the severity of pancreatic fibrosis aggravates, the proportion of M2/M1 macrophage cytokines in the pancreas increases. The discovery of macrophages in the pathogenesis of pancreatitis has promoted the research of targeted drugs, which provides great potential for the effective treatment of pancreatitis. This paper provides an overview of the roles of various macrophages in the pathogenesis of pancreatitis and the current research status of pancreatitis immunotherapy targeting macrophages. The findings addressed in this review are of considerable significance for understanding the pivotal role of macrophages in pancreatitis.


Subject(s)
Macrophages/physiology , Pancreatitis/etiology , Animals , Humans , Immunotherapy , Kupffer Cells/physiology , Pancreatitis/drug therapy , Pancreatitis, Chronic/drug therapy , Pancreatitis, Chronic/etiology
16.
ACS Chem Biol ; 15(9): 2476-2484, 2020 09 18.
Article in English | MEDLINE | ID: mdl-32786262

ABSTRACT

The indolizidine alkaloid swainsonine (SW) is a deadly mycotoxin to livestock that can be produced by different plant-associated fungi, including the endophytic entomopathogenic fungi Metarhizium species. The SW biosynthetic gene cluster has been identified but the genetic mechanism of SW biosynthesis remains obscure. To unveil the SW biosynthetic pathway, we performed gene deletions in M. robertsii, heterologous expression of a core biosynthetic gene, substrate feedings, mass spectrometry, and bioassay analyses in this study. It was unveiled that SW is produced via a multibranched pathway by the hybrid nonribosomal peptide-polyketide synthase (NRPS-PKS) gene cluster in M. robertsii. The precursor pipecolic acid can be converted from lysine by both the SW biosynthetic cluster and the unclustered genes such as lysine cyclodeaminase. The hybrid NRPS-PKS enzyme produces three intermediates with and without domain skipping. Intriguingly, the biosynthetic process is coupled with the cis to trans nonenzymatic epimerization of C1-OH for both hydroxyl- and dihydroxyl-indolizidine intermediates. We also found that SW production was dispensable for fungal colonization of plants and infection of insect hosts. Functional characterization of the SW biosynthetic genes in this study may benefit the safe use of Metarhizium fungi as insect biocontrol agents and the management of livestock pastures from SW contamination by genetic manipulation of the toxin-producing fungi.


Subject(s)
Mycotoxins/biosynthesis , Swainsonine/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism , Metarhizium/genetics , Metarhizium/metabolism , Multigene Family , Peptide Synthases/genetics , Peptide Synthases/metabolism , Polyketide Synthases/genetics , Polyketide Synthases/metabolism , Protein Domains
17.
Appl Environ Microbiol ; 86(20)2020 10 01.
Article in English | MEDLINE | ID: mdl-32769188

ABSTRACT

Metarhizium spp. are well-known biocontrol agents used worldwide to control different insect pests. Keto-acid reductoisomerase (ILVC) is a key enzyme for branched-chain amino acid (BCAA) biosynthesis, and it regulates many physiological activities. However, its functions in insect-pathogenic fungi are poorly understood. In this work, we identified MrilvC in M. robertsii and dissected its roles in fungal growth, conidiation, germination, destruxin biosynthesis, environmental stress response, and insecticidal virulence. BCAA metabolism affects conidial yields and germination. However, BCAAs cannot recover the conidial germination of an MrilvC-deficient strain. Further feeding assays with intermediates showed that some conidia of the ΔMrilvC mutant start to germinate. Therefore, it is the germination defect that causes the complete failures of conidial penetration and pathogenicity in the ΔMrilvC mutant. In conclusion, we found intermediates in BCAA biosynthesis are indispensable for Metarhizium robertsii conidial germination. This study will advance our understanding of the fungal germination mechanism.IMPORTANCE Branched-chain amino acid (BCAA) metabolism plays a significant role in many biological activities beyond protein synthesis. Spore germination initiates the first stage of vegetative growth, which is critical for the virulence of pathogenic fungi. In this study, we demonstrated that the keto-acid reductoisomerase MrILVC, a key enzyme for BCAA biosynthesis, from the insect-pathogenic fungus Metarhizium robertsii is associated with conidial germination and fungal pathogenicity. Surprisingly, the germination of the ΔMrilvC mutant was restored when supplemented with the intermediates of BCAA metabolism rather than three BCAAs. The result was significantly different from that of plant-pathogenic fungi. Therefore, this report highlights that the intermediates in BCAA biosynthesis are indispensable for conidial germination of M. robertsii.


Subject(s)
Amino Acids, Branched-Chain/biosynthesis , Metarhizium/physiology , Spores, Fungal/growth & development , Metarhizium/enzymology , Metarhizium/growth & development
18.
Nanomedicine ; 29: 102233, 2020 10.
Article in English | MEDLINE | ID: mdl-32522710

ABSTRACT

Ultra-small superparamagnetic iron oxide (USPIO) nanoparticles appear to be promising tools for MR lymphography due to their unique magnetic properties. In clinical diagnosis, the effectiveness of USPIO will greatly affect the clinician's judgment to the enhanced MR images. In this study, we evaluated the effectiveness of CS015, a PAA-coated USPIO, with subcutaneous and intravenous administration. It appeared that subcutaneously injected particles had much higher efficiency to reach lymph nodes, and even worked at a very small dose 0.075 µmol/kg. Further, we compared CS015 with ferumoxytol and ferumoxtran-10 in MR lymphography and found that CS015 had the best performance. And the lymph node metastases in New Zealand rabbits were successfully detected using CS015 with one single dose. These merits of CS015 make it a promising MR lymphography contrast agent with potential applications in cancer therapy.


Subject(s)
Contrast Media/pharmacology , Lymph Nodes/ultrastructure , Lymphography/methods , Magnetic Resonance Imaging/methods , Animals , Contrast Media/chemistry , Dextrans/chemistry , Dextrans/pharmacology , Humans , Image Enhancement/methods , Lymph Nodes/drug effects , Lymphatic Metastasis/diagnostic imaging , Magnetite Nanoparticles/chemistry , Rabbits
19.
Fitoterapia ; 146: 104671, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32565347

ABSTRACT

Two new cyclopentapeptides, basidiosins A and B (1 and 2) were isolated from the mycelia extracts of entomophthoralean fungus Basidiobolus meristosporus RCEF 4516. The structures were determined based on spectroscopic methods, and the absolute config urations were assigned by Marfey's method on their acid hydrolyzates. Compounds 1 and 2 were identified as cyclo(L-Thr-L-Leu- L-Ile-D-Tyr-D-Thr) and cyclo(L-Thr-L-Leu-L-Val-D-Val-D-Ser), respectively. They were evaluated for the biological activities including antibacterial, antifungal and antioxidative activities. Furthermore, the biosynthetic pathway of 1 was proposed by bioinformatic analysis. This is the first study on the isolation of natural products from Basidiobolus fungus.


Subject(s)
Biological Products/pharmacology , Entomophthorales/chemistry , Antifungal Agents/isolation & purification , Antifungal Agents/pharmacology , Biological Products/isolation & purification , China , Entomophthorales/genetics , Forests , Molecular Structure , Multigene Family , Mycelium/chemistry , Peptide Fragments/isolation & purification , Peptide Fragments/pharmacology , Soil Microbiology
20.
Oncol Rep ; 42(4): 1589-1597, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31524270

ABSTRACT

Acute pancreatitis (AP) is an inflammatory disease with high morbidity and mortality rates. Pancreatic ductal cells are the most susceptible of all cell types that are exposed to the noxious stimuli of pancreatitis. Our previous studies demonstrated that emodin, a natural product extracted from Rheum palmatum L., protected pancreatic acinar cells from injutyh due to its anti­inflammatory activity. In the present study, in order to investigate the protective effects and molecular mechanisms of action of emodin on injured pancreatic ductal cells, an adenosine triphosphate (ATP)­induced model of cell injury was established using the human pancreatic ductal epithelial cell line, HPDE6­C7. The results revealed that emodin attenuated ATP­induced HPDE6­C7 cell injury by decreasing the levels of inflammatory factors, including interleukin (IL)­1ß and IL­18. Furthermore, emodin significantly downregulated the protein levels of purinergic receptor P2X, ligand­gated ion channel, 7 (P2X7), NOD­like receptor protein 3 (NLRP3), apoptosis­associated speck­like protein containing a CARD (ASC) and caspase­1 in the injured HPDE6­C7 cells. The results also indicated that emodin attenuated HPDE6­C7 cell injury at least partially through the inhibition of the P2X7/NLRP3 signaling pathway. The protective effects of emodin were abrogated upon pre­treatment with P2X7 overexpression plasmid, which further confirmed that the P2X7 signaling pathway is the drug target of the effects of emodin against ATP­induced pancreatic ductal cell injury. Collectively, the findings of this study demonstrate that emodin attenuates ATP­induced pancreatic ductal cell injury in AP mainly through the inhibition of the P2X7/NLRP3 signaling pathway. This study suggests that emodin may be further developed for its application in future medical therapy.

SELECTION OF CITATIONS
SEARCH DETAIL
...