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1.
Braz. J. Pharm. Sci. (Online) ; 58: e19897, 2022. tab, graf
Article in English | LILACS | ID: biblio-1383986

ABSTRACT

Abstract Candida glabrata infections are responsible for deaths of people globally. Fluconazole is known to be less effective against C. glabrata, which developed many strategies to evade being destroyed by fluconazole. To achieve enhanced efficacy of fluconazole against C. glabrata, the interaction of fluconazole with sodium bicarbonate was investigated using the CLSI guidelines. The efficacy of fluconazole alone and in combination with sodium bicarbonate was evaluated using the time-kill and phospholipase production assays. Eventually, the expression of PLB was assessed using semi-quantitative RT-PCR to investigate the inhibitory properties of fluconazole alone and in combination with sodium bicarbonate against C. glabrata. The fluconazole/sodium bicarbonate combination displayed synergistic and antagonistic effects (FICI= 0.375-4.25). In C. glabrata ATCC, SN 152, and SN 164, the fluconazole/sodium bicarbonate combination exhibited a significant fungicidal activity (p< 0.05) but antagonistic effect in the case of SN 283. With exception of SN 283, a significant reduction was noted in phospholipase production in clinical isolates of C. glabrata treated with fluconazole/sodium bicarbonate combination. The PLB was down-regulated significantly by 0.168-0.515 fold in C. glabrata treated with fluconazole/sodium bicarbonate. The results suggested fluconazole/sodium bicarbonate to have a potential synergistic interaction in C. glabrata, and the underlying mechanism may be associated with phospholipase gene


Subject(s)
Phospholipases/antagonists & inhibitors , Fluconazole/agonists , Sodium Bicarbonate/agonists , Candida glabrata/pathogenicity , Efficacy , Infections
2.
Toxins (Basel) ; 13(1)2021 01 05.
Article in English | MEDLINE | ID: mdl-33466223

ABSTRACT

Massive, Africanized honeybee attacks have increased in Brazil over the years. Humans and animals present local and systemic effects after envenomation, and there is no specific treatment for this potentially lethal event. This study evaluated the ability of a new Apilic antivenom, which is composed of F(ab')2 fraction of specific immunoglobulins in heterologous and hyperimmune equine serum, to neutralize A. mellifera venom and melittin, in vitro and in vivo, in mice. Animal experiments were performed in according with local ethics committee license (UFRJ protocol no. DFBCICB072-04/16). Venom dose-dependent lethality was diminished with 0.25-0.5 µL of intravenous Apilic antivenom/µg honeybee venom. In vivo injection of 0.1-1 µg/g bee venom induced myotoxicity, hemoconcentration, paw edema, and increase of vascular permeability which were antagonized by Apilic antivenom. Cytotoxicity, assessed in renal LLC-PK1 cells and challenged with 10 µg/mL honeybee venom or melittin, was neutralized by preincubation with Apilic antivenom, as well the hemolytic activity. Apilic antivenom inhibited phospholipase and hyaluronidase enzymatic activities. In flow cytometry experiments, Apilic antivenom neutralized reduction of cell viability due to necrosis by honeybee venom or melittin. These results showed that this antivenom is effective inhibitor of honeybee venom actions. Thus, this next generation of Apilic antivenom emerges as a new promising immunobiological product for the treatment of massive, Africanized honeybee attacks.


Subject(s)
Antivenins/therapeutic use , Bee Venoms/antagonists & inhibitors , Bites and Stings/drug therapy , Melitten/antagonists & inhibitors , Animals , Antibodies/blood , Bees , Brazil , Cell Line , Cell Survival , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical , Female , Hemolysis/drug effects , Horses , Hyaluronoglucosaminidase/antagonists & inhibitors , Immunoglobulin Fab Fragments/therapeutic use , Injections, Intradermal , LLC-PK1 Cells , Lethal Dose 50 , Male , Mice , Models, Animal , Neutralization Tests , Phospholipases/antagonists & inhibitors , Swine
3.
J Med Chem ; 64(1): 481-515, 2021 01 14.
Article in English | MEDLINE | ID: mdl-33382264

ABSTRACT

N-Acylphosphatidylethanolamine phospholipase D (NAPE-PLD) is regarded as the main enzyme responsible for the biosynthesis of N-acylethanolamines (NAEs), a family of bioactive lipid mediators. Previously, we reported N-(cyclopropylmethyl)-6-((S)-3-hydroxypyrrolidin-1-yl)-2-((S)-3-phenylpiperidin-1-yl)pyrimidine-4-carboxamide (1, LEI-401) as the first potent and selective NAPE-PLD inhibitor that decreased NAEs in the brains of freely moving mice and modulated emotional behavior [Mock Nat Chem. Biol., 2020, 16, 667-675]. Here, we describe the structure-activity relationship (SAR) of a library of pyrimidine-4-carboxamides as inhibitors of NAPE-PLD that led to the identification of LEI-401. A high-throughput screening hit was modified at three different substituents to optimize its potency and lipophilicity. Conformational restriction of an N-methylphenethylamine group by replacement with an (S)-3-phenylpiperidine increased the inhibitory potency 3-fold. Exchange of a morpholine substituent for an (S)-3-hydroxypyrrolidine reduced the lipophilicity and further increased activity by 10-fold, affording LEI-401 as a nanomolar potent inhibitor with drug-like properties. LEI-401 is a suitable pharmacological tool compound to investigate NAPE-PLD function in vitro and in vivo.


Subject(s)
Amides/chemistry , Carboxylic Acids/chemistry , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Phosphatidylethanolamines/chemistry , Phospholipases/antagonists & inhibitors , Pyrimidines/chemistry , Carboxylic Acids/pharmacology , Phospholipases/chemistry , Pyrimidines/pharmacology , Structure-Activity Relationship
4.
J Med Chem ; 63(17): 9340-9359, 2020 09 10.
Article in English | MEDLINE | ID: mdl-32787138

ABSTRACT

The phospholipase A and acyltransferase (PLAAT) family of cysteine hydrolases consists of five members, which are involved in the Ca2+-independent production of N-acylphosphatidylethanolamines (NAPEs). NAPEs are lipid precursors for bioactive N-acylethanolamines (NAEs) that are involved in various physiological processes such as food intake, pain, inflammation, stress, and anxiety. Recently, we identified α-ketoamides as the first pan-active PLAAT inhibitor scaffold that reduced arachidonic acid levels in PLAAT3-overexpressing U2OS cells and in HepG2 cells. Here, we report the structure-activity relationships of the α-ketoamide series using activity-based protein profiling. This led to the identification of LEI-301, a nanomolar potent inhibitor for the PLAAT family members. LEI-301 reduced the NAE levels, including anandamide, in cells overexpressing PLAAT2 or PLAAT5. Collectively, LEI-301 may help to dissect the physiological role of the PLAATs.


Subject(s)
Acyltransferases/antagonists & inhibitors , Amides/chemistry , Amides/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Phospholipases/antagonists & inhibitors , Acyltransferases/chemistry , Hep G2 Cells , Humans , Models, Molecular , Phospholipases/chemistry , Protein Conformation , Structure-Activity Relationship
5.
Sci Rep ; 10(1): 8911, 2020 06 02.
Article in English | MEDLINE | ID: mdl-32488004

ABSTRACT

The endothelial lipase LIPG possesses serine phospholipase activity and is involved in lipoprotein metabolism. Our previous studies have revealed that LIPG overexpression is required for tumor formation and metastasis of human basal-like triple-negative breast cancer (TNBC). We also demonstrated that LIPG differentially regulates TNBC malignancy through its enzymatic and non-enzymatic functions. The present studies were aimed at determining how XEN445, a specific inhibitor targeting LIPG phospholipase activity, impacts on TNBC tumor formation and malignant features. We established a cell-based LIPG enzymatic assay system to measure the inhibitory effect of XEN445 on LIPG phospholipase activity and determine its IC50. We found that XEN445 preferentially inhibited the proliferation of LIPG-expressing TNBC cells but not LIPG-negative luminal breast cancer cells. XEN445 inhibited the self-renewal of cancer stem cells (CSCs) in vitro and TNBC tumor formation in vivo. However, XEN445 had no inhibitory effect on the invasiveness and CSC stemness of TNBC cells. Our studies suggest that targeting both LIPG enzymatic and non-enzymatic functions is an important strategy for the treatment of TNBC.


Subject(s)
Lipase/antagonists & inhibitors , Triple Negative Breast Neoplasms/enzymology , Benzoates/pharmacology , Blotting, Western , Cell Line, Tumor , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Female , Flow Cytometry , Humans , Inhibitory Concentration 50 , Lipase/metabolism , Neoplasm Invasiveness , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/enzymology , Phospholipases/antagonists & inhibitors , Phospholipases/metabolism , Pyrrolidines/pharmacology , Triple Negative Breast Neoplasms/drug therapy
6.
FEMS Yeast Res ; 20(3)2020 05 01.
Article in English | MEDLINE | ID: mdl-32324227

ABSTRACT

Candida albicans has several virulence factors at its disposal, including yeast-hyphal transition associated with biofilm formation, phospholipases, proteases and hemolytic activity, all of which contribute to its pathogenesis. We used synthetic derivative LL-III/43 of antimicrobial peptide lasioglossin LL-III to enhance effect of azoles on attenuation of C. albicans virulence factors. LL-III/43 was able to inhibit initial adhesion or biofilm formation of C. albicans strains at 50 µM. Azoles, however, were ineffective at this concentration. Using fluorescently labeled LL-III/43, we observed that peptide covered C. albicans cells, partially penetrated through their membranes and then accumulated inside cells. LL-III/43 (25 µM) in combination with clotrimazole prevented biofilm formation already at 3.1 µM clotrimazole. Neither LL-III/43 nor azoles were able to significantly inhibit phospholipases, proteases, or hemolytic activity of C. albicans. LL-III/43 (25 µM) and clotrimazole (50 µM) in combination decreased production of these virulence factors, and it completely attenuated its hemolytic activity. Scanning electron microscopy showed that LL-III/43 (50 µM) prevented C. albicans biofilm formation on Ti-6Al-4 V alloy used in orthopedic surgeries and combination of LL-III/43 (25 µM) with clotrimazole (3.1 µM) prevented biofilm formation on urinary catheters. Therefore, mixture of LL-III/43 and clotrimazole is suitable candidate for future pharmaceutical research.


Subject(s)
Antifungal Agents/pharmacology , Antimicrobial Cationic Peptides/pharmacokinetics , Azoles/pharmacology , Biofilms/drug effects , Candida albicans/drug effects , Hemolysis/drug effects , Peptide Hydrolases/metabolism , Phospholipases/antagonists & inhibitors , Antimicrobial Cationic Peptides/chemical synthesis , Biofilms/growth & development , Erythrocytes/drug effects , Humans , Hydrophobic and Hydrophilic Interactions/drug effects , Virulence Factors
7.
J Basic Clin Physiol Pharmacol ; 32(6): 1121-1130, 2020 Dec 14.
Article in English | MEDLINE | ID: mdl-34898137

ABSTRACT

OBJECTIVES: Snakebite envenoming is an important public health problem that threatens the lives of healthy individuals especially in many tropical countries like Nigeria. Antivenins, the only efficient approach for snakebite envenoming, are limited in their efficacy in the neutralization of local tissue damage. Snake venom phospholipase A2 (PLA2), protease, hyaluronidase and l-amino acid oxidase (LAAO) are the major hydrolytic enzymes involve in local tissue damage. Therefore, this study evaluates the inhibitory effect of kolaviron (KV) against Naja n. nigricollis (NNN) snake venom hydrolytic enzymes involved in local tissue damage. METHODS: Kolaviron was evaluated for its ability to inhibit the hydrolytic enzyme activities of NNN venom phospholipase A2 (PLA2), protease, hyaluronidase and l-amino acid oxidase (LAAO). Present study also deals with the neutralization of NNN venom enzyme(s) induced complications such as myotoxic, edemic, hemolytic and procoagulant effects. RESULTS: Kolaviron inhibited the PLA2, protease, hyaluronidase and LAAO enzyme activities of NNN venom in a dose-dependent manner. Furthermore, myotoxic, edemic, hemolytic and procoagulant effects induced by NNN venom enzyme were neutralized significantly (p<0.05) when different doses of KV were pre-incubated with venom before assays. CONCLUSIONS: These findings clearly present kolaviron as a potent inhibitor against NNN venom hydrolytic enzymes involved in local tissue damage and may act by either forming an inhibitor-enzyme complex that restricts the substrate availability to the enzyme or direct binding to the enzyme active site that affects the enzyme activity thereby mitigating venom-induced toxicity.


Subject(s)
Enzyme Inhibitors/pharmacology , Flavonoids/pharmacology , Snake Bites , Snake Venoms , Humans , Hyaluronoglucosaminidase/antagonists & inhibitors , L-Amino Acid Oxidase/antagonists & inhibitors , Peptide Hydrolases , Phospholipases/antagonists & inhibitors , Polyesters , Protease Inhibitors , Snake Bites/drug therapy , Snake Venoms/toxicity
8.
Free Radic Biol Med ; 144: 6-15, 2019 11 20.
Article in English | MEDLINE | ID: mdl-30849488

ABSTRACT

The review summarizes and critically discusses data on biochemical and free-radical transformations of glycerophospholipids. The results presented therein demonstrate that hydroxyl-containing glycerophospholipids, such as cardiolipin, lyso-lipids and others, can undergo fragmentation upon interaction with radical agents forming the biologically active products. Hydrolysis of glycerophospholipids catalyzed by different phospholipases was shown to yield compounds, which can be involved in the free-radical fragmentation leading to significant changes in structures of original lipids.


Subject(s)
Glycerophospholipids/chemistry , Lipid Peroxides/chemistry , Lipoxygenases/chemistry , Lysophospholipids/chemistry , Phospholipases/chemistry , Animals , Antioxidants/chemistry , Antioxidants/pharmacology , Biocatalysis , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Glycerophospholipids/metabolism , Humans , Hydrolysis , Lipid Peroxidation/drug effects , Lipid Peroxides/metabolism , Lipoxygenases/metabolism , Lysophospholipids/metabolism , Phospholipases/antagonists & inhibitors , Phospholipases/metabolism , Plants/chemistry , Plants/metabolism , Quinones/chemistry , Quinones/pharmacology
9.
J Enzyme Inhib Med Chem ; 34(1): 672-683, 2019 Dec.
Article in English | MEDLINE | ID: mdl-30821525

ABSTRACT

Some new 3H-quinazolin-4-one derivatives were synthesised and screened for anticancer, antiphospholipases, antiproteases, and antimetabolic syndrome activities. Compound 15d was more potent in reducing the cell viabilities of HT-29 and SW620 cells lines to 38%, 36.7%, compared to 5-FU which demonstrated cell viabilities of 65.9 and 42.7% respectively. The IC50 values of 15d were ∼20 µg/ml. Assessment of apoptotic activity revealed that 15d decreased the cell viability by down regulating Bcl2 and BclxL. Moreover, compounds, 8j, 8d/15a/15e, 5b, and 8f displayed lowered IC50 values than oleanolic acid against proinflammatory isoforms of hGV, hG-X, NmPLA2, and AmPLA2. In addition, 8d, 8h, 8j, 15a, 15b, 15e, and 15f showed better anti-α-amylase than quercetin, whereas 8g, 8h, and 8i showed higher anti-α-glucosidase activity than allopurinol. Thus, these compounds can be considered as potential antidiabetic agents. Finally, none of the compounds showed higher antiproteases or xanthine oxidase activities than the used reference drugs.


Subject(s)
Antineoplastic Agents/pharmacology , Enzyme Inhibitors/pharmacology , Metabolic Syndrome/drug therapy , Peptide Hydrolases/metabolism , Phospholipases/antagonists & inhibitors , Quinazolinones/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , HT29 Cells , Humans , Metabolic Syndrome/metabolism , Molecular Structure , Phospholipases/metabolism , Quinazolinones/chemical synthesis , Quinazolinones/chemistry , Structure-Activity Relationship , Tumor Cells, Cultured
10.
Am J Physiol Cell Physiol ; 316(2): C162-C174, 2019 02 01.
Article in English | MEDLINE | ID: mdl-30462540

ABSTRACT

Mammalian glycerophosphodiesterases (GDEs) were recently shown to be involved in multiple cellular signaling pathways. This study showed that decreased GDE5 expression results in accumulation of intracellular glycerophosphocholine (GPC), showing that GDE5 is actively involved in GPC/choline metabolism in 3T3-L1 adipocytes. Using 3T3-L1 adipocytes, we further studied the biological significance of GPC/choline metabolism during adipocyte differentiation. Inhibition of GDE5 suppressed the formation of lipid droplets, which is accompanied by the decreased expression of adipocyte differentiation markers. We further showed that the decreased GDE5 expression suppressed mitotic clonal expansion (MCE) of preadipocytes. Decreased expression of CTP: phosphocholine cytidylyltransferase (CCTß), a rate-limiting enzyme for phosphatidylcholine (PC) synthesis, is similarly able to inhibit MCE and PC synthesis; however, the decreased GDE5 expression resulted in accumulation of intracellular GPC but did not affect PC synthesis. Furthermore, we showed that mRNAs of proteoglycans and transporters for organic osmolytes are significantly upregulated and that intracellular amino acids and urea levels are altered in response to GDE5 inhibition. Finally, we showed that reduction of GDE5 expression increased lactate dehydrogenase release from preadipocytes. These observations indicate that decreased GDE5 expression can suppress adipocyte differentiation not through the PC pathway but possibly by intracellular GPC accumulation. These results provide insight into the roles of mammalian GDEs and their dependence upon osmotic regulation by altering intracellular GPC levels.


Subject(s)
Adipogenesis/physiology , Glycerylphosphorylcholine/metabolism , Intracellular Fluid/metabolism , Mitosis/physiology , Phospholipases/antagonists & inhibitors , Phospholipases/metabolism , 3T3-L1 Cells , Adipogenesis/drug effects , Animals , Intracellular Fluid/drug effects , Mice , Mitosis/drug effects , NIH 3T3 Cells , RNA, Small Interfering/pharmacology
11.
Drug Discov Today Technol ; 29: 51-60, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30471674

ABSTRACT

Over the past two decades, there has been an increasing interest in the therapeutic potential of organoboron reagents due to the discovery of bortezomib (Velcade). This has motivated synthetic chemists to develop novel routes for the preparation of heteroatom-rich boron-containing molecules (BCMs). In particular, the development of borylated building blocks has provided facile access to difficult-to-access heteroatom-rich BCMs. In this review, we will discuss the methods used to prepare boron-containing molecules of biological relevance from multicomponent reactions with borylated building blocks.


Subject(s)
Boron Compounds/chemical synthesis , Chemistry Techniques, Synthetic/methods , Chemistry, Pharmaceutical/methods , Phospholipases/antagonists & inhibitors , Bortezomib/chemistry , Cyanides/chemical synthesis , Molecular Structure , Phospholipases A2 , Proteasome Inhibitors/chemistry
12.
Sci Rep ; 8(1): 7245, 2018 05 08.
Article in English | MEDLINE | ID: mdl-29740008

ABSTRACT

The bacterial storage compound poly-ß-hydroxybutyrate, a polymer of the short-chain fatty acid 3-hydroxybutyrate, has been reported to protect various aquatic animals from bacterial disease. In order to obtain a better mechanistic insight, we aimed to (1) investigate whether 3-hydroxybutyrate is released from poly-ß-hydroxybutyrate within sterile brine shrimp larvae, (2) determine the impact of 3-hydroxybutyrate on the virulence of Vibrio campbellii to brine shrimp larvae and on its cell density in the shrimp, and (3) determine the impact of this compound on virulence factor production in the pathogen. We detected 3-hydroxybutyrate in poly-ß-hydroxybutyrate-fed brine shrimp, resulting in 24 mM 3-hydroxybutyrate in the intestinal tract of shrimp reared in the presence of 1000 mg l-1 poly-ß-hydroxybutyrate. We further demonstrate that this concentration of 3-hydroxybutyrate does not affect the growth of V. campbellii, whereas it decreases the production of different virulence factors, including hemolysin, phospholipase and protease activities, and swimming motility. We hypothesize that by affecting all these virulence factors at once, 3-hydroxybutyrate (and thus also poly-ß-hydroxybutyrate) can exert a significant impact on the virulence of V. campbellii. This hypothesis was confirmed in a challenge test showing that 3-hydroxybutyrate protected gnotobiotic brine shrimp from pathogenic V. campbellii, without affecting the number of host-associated vibrios.


Subject(s)
3-Hydroxybutyric Acid/pharmacology , Antidotes/pharmacology , Enzyme Inhibitors/pharmacology , Hydroxybutyrates/pharmacology , Polyesters/pharmacology , Vibrio/drug effects , Virulence Factors/antagonists & inhibitors , 3-Hydroxybutyric Acid/chemistry , Animals , Antidotes/chemistry , Artemia/drug effects , Artemia/microbiology , Enzyme Inhibitors/chemistry , Hemolysin Proteins/antagonists & inhibitors , Hemolysin Proteins/toxicity , Hydrogen-Ion Concentration , Hydrolysis , Hydroxybutyrates/chemistry , Intestines/drug effects , Intestines/microbiology , Larva/drug effects , Larva/microbiology , Peptide Hydrolases/toxicity , Phospholipases/antagonists & inhibitors , Phospholipases/toxicity , Polyesters/chemistry , Vibrio/growth & development , Vibrio/metabolism , Vibrio/pathogenicity , Virulence Factors/toxicity
13.
J Exp Clin Cancer Res ; 37(1): 82, 2018 Apr 13.
Article in English | MEDLINE | ID: mdl-29653539

ABSTRACT

BACKGROUND: Our previous study demonstrates that Citrus-limon derived nanovesicles are able to decrease colon cancer cell viability, and that this effect is associated with the downregulation of the intracellular phospholipase DDHD domain-containing protein 1 (DDHD1). While few studies are currently available on the contribution of DDHD1 in neurological disorders, there is no information on its role in cancer. This study investigates the role of DDHD1 in colon cancer. METHODS: DDHD1 siRNAs and an overexpression vector were transfected into colorectal cancer and normal cells to downregulate or upregulate DDHD1 expression. In vitro and in vivo assays were performed to investigate the functional role of DDHD1 in colorectal cancer cell growth. Quantitative proteomics using SWATH-MS was performed to determinate the molecular effects induced by DDHD1 silencing in colorectal cancer cells. RESULTS: The results indicate that DDHD1 supports colon cancer cell proliferation and survival, since its downregulation reduces in vitro colon cancer cell viability and increases apoptosis rate, without affecting normal cells. On the contrary, in vivo studies demonstrate that the xenograft tumors, derived from DDHD1-overexpressing cells, have a higher proliferation rate compared to control animals. Additionally, we found that functional categories, significantly affected by DDHD1 silencing, were specifically related to cancer phenotype and for the first time associated to DDHD1 activity. CONCLUSIONS: In conclusion, this study provides the first evidence confirming the role of DDHD1 in cancer, providing a possibility to define a new target to design more effective therapies for colon cancer patients.


Subject(s)
Antineoplastic Agents/pharmacology , Biomarkers, Tumor , Colorectal Neoplasms/metabolism , Molecular Targeted Therapy , Phospholipases/antagonists & inhibitors , Animals , Antineoplastic Agents/therapeutic use , Apoptosis/genetics , Cell Line, Tumor , Cell Proliferation , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/genetics , Computational Biology/methods , Disease Models, Animal , Female , Gene Expression Profiling , Gene Ontology , Gene Regulatory Networks , Gene Silencing , Humans , MAP Kinase Signaling System , Mice , Phospholipases/genetics , Phospholipases/metabolism , Signal Transduction , Xenograft Model Antitumor Assays
14.
New Phytol ; 219(1): 324-335, 2018 07.
Article in English | MEDLINE | ID: mdl-29577317

ABSTRACT

Plants evolved disease resistance (R) proteins that recognize corresponding pathogen effectors and activate effector-triggered immunity (ETI). However, it is largely unknown why, in some cases, a suppressor of ETI exists in plants. Arabidopsis SOBER1 (Suppressor of AvrBsT-elicited Resistance 1) was identified previously as a suppressor of Xanthomonas acetyltransferase effector AvrBsT-triggered immunity. Nevertheless, the extent to which SOBER1 suppresses ETI is unclear. Here, we identified SOBER1 as a suppressor of Pseudomonas acetyltransferase effector HopZ5-triggered immunity in Arabidopsis using recombinant inbred lines. Further analysis showed that SOBER1 suppresses immunity triggered by multiple bacterial acetyltransferases. Interestingly, SOBER1 interferes with the immunity signalling activated by some but not all tested acetyltransferase effectors, indicating that SOBER1 might target components that are shared between several ETI pathways.


Subject(s)
Arabidopsis Proteins/immunology , Arabidopsis/physiology , Carboxylic Ester Hydrolases/immunology , Plant Immunity/physiology , Acetyltransferases/genetics , Acetyltransferases/immunology , Acetyltransferases/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/immunology , Bacterial Proteins/metabolism , Carboxylic Ester Hydrolases/genetics , Carboxylic Ester Hydrolases/metabolism , Histidine/metabolism , Host-Pathogen Interactions/immunology , Phospholipases/antagonists & inhibitors , Phospholipases/metabolism , Plants, Genetically Modified , Pseudomonas syringae/pathogenicity , Serine/metabolism , Xanthomonas campestris/metabolism , Xanthomonas campestris/pathogenicity
15.
Int J Antimicrob Agents ; 51(1): 107-114, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28943366

ABSTRACT

Candida spp. are the primary opportunistic pathogens of nosocomial fungal infections, causing both superficial and life-threatening systemic infections. Combination therapy for fungal infections has attracted considerable attention, especially for those caused by drug-resistant fungi. Gentamicin (GM), an aminoglycoside antibiotic, has weak antifungal activity against Fusarium spp. The aim of this study was to investigate the interactions of GM with azoles against Candida spp. and the underlying mechanisms. In a chequerboard assay, GM was found not only to work synergistically with azoles against planktonic cells of drug-resistant Candida albicans with a fractional inhibitory concentration index (FICI) of 0.13-0.14, but also synergised with fluconazole (FLC) against C. albicans biofilms pre-formed in <12 h. Synergism of GM with FLC was also confirmed in vivo in a Galleria mellonella infection model. In addition, mechanism studies showed that GM not only suppressed the efflux pump of resistant C. albicans in a dose-dependent manner but also inhibited extracellular phospholipase activity of resistant C. albicans when combined with FLC. These findings suggest that GM enhances the efficacy of azoles against resistant C. albicans via efflux inhibition and decreased activity of extracellular phospholipase.


Subject(s)
Antifungal Agents/pharmacology , Biofilms/drug effects , Candida albicans/drug effects , Fluconazole/pharmacology , Gentamicins/pharmacology , Moths/microbiology , Animals , Cross Infection/microbiology , Drug Resistance, Fungal , Drug Synergism , Humans , Larva/microbiology , Membrane Transport Proteins/drug effects , Microbial Sensitivity Tests , Phospholipases/antagonists & inhibitors
16.
Biochemistry ; 57(5): 827-838, 2018 Feb 06.
Article in English | MEDLINE | ID: mdl-29278326

ABSTRACT

Deleterious mutations in the serine lipase DDHD2 are a causative basis of complex hereditary spastic paraplegia (HSP, subtype SPG54) in humans. We recently found that DDHD2 is a principal triglyceride hydrolase in the central nervous system (CNS) and that genetic deletion of this enzyme in mice leads to ectopic lipid droplet (LD) accumulation in neurons throughout the brain. Nonetheless, how HSP-related mutations in DDHD2 relate to triglyceride metabolism and LD formation remains poorly understood. Here, we have characterized a set of HSP-related mutations in DDHD2 and found that they disrupt triglyceride hydrolase activity in vitro and impair the capacity of DDHD2 to protect cells from LD accumulation following exposure to free fatty acid, an outcome that was also observed with a DDHD2-selective inhibitor. We furthermore isolated and characterized LDs from brain tissue of DDHD2-/- mice, revealing that they contain both established LD-associated proteins identified previously in other organs and CNS-enriched proteins, including several proteins with genetic links to human neurological disease. These data, taken together, indicate that the genetic inactivation of DDHD2, as caused by HSP-associated mutations, substantially perturbs lipid homeostasis and the formation and content of LDs, underscoring the importance of triglyceride metabolism for normal CNS function and the key role that DDHD2 plays in this process.


Subject(s)
Lipid Droplet Associated Proteins/analysis , Lipid Droplets/chemistry , Nerve Tissue Proteins/physiology , Phospholipases/physiology , Animals , Brain Chemistry , Catalytic Domain/drug effects , Fatty Acids/metabolism , Homeostasis , Humans , Mice , Mice, Knockout , Microscopy, Confocal , Mutagenesis, Site-Directed , Nerve Tissue Proteins/antagonists & inhibitors , Nerve Tissue Proteins/genetics , Organ Specificity , Phospholipases/antagonists & inhibitors , Phospholipases/genetics , Phospholipases A1/deficiency , Recombinant Proteins/metabolism , Spastic Paraplegia, Hereditary/genetics , Triglycerides/metabolism
17.
J Ethnopharmacol ; 213: 350-358, 2018 Mar 01.
Article in English | MEDLINE | ID: mdl-29183746

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Extracts of leaves and bark of Aniba fragrans are used as tea (decoction) to treat snakebites in communities in the Brazilian Amazon. The aqueous extract of the leaves of A. fragrans has been proven to be effective against Bothrops venom, but only when pre-incubated with the venom. This study sought to assess the potential of different types of extract of this species to inhibit the biological activities of Bothrops atrox venom (BaV) when used the same way as in folk medicine. The main classes of secondary metabolites and the concentrations of phenolics in the extracts were also determined. MATERIALS AND METHODS: Four types of extract of A. fragrans were prepared: aqueous extract of the leaf (AEL), aqueous extract of the bark (AEB), hydroalcoholic leaf extract (HLE) and extract of the residue from hydrodistillation of the leaf (ERHL). The phytochemical profiles of the aqueous extracts were determined using thin layer chromatography (TLC), and the concentrations of phenolics were measured by colorimetric assays. To investigate the potential of the extracts to inhibit the biological activities of BaV, in vitro tests for antiphospholipase and antifibrinolytic activities were performed. In vivo tests for antihemorrhagic and antidefibrinating activities were also carried out, as well as antimicrobial tests for activity against the main bacteria found in the oral cavity of snakes. Interaction between the extracts and the proteins in BaV was assessed by electrophoresis (SDS-PAGE) and Western blot (WB). The cytotoxicity of the extracts was assessed in a strain of MRC-5 human fibroblasts. RESULTS: Terpenoids, flavonoids and condensed and hydrolysable tannins were detected in all the extracts. Metabolites such as coumarins, fatty acids and alkaloids were present in some extracts but not in others, indicating different phytochemical profiles. Phenolics content varied between extracts, and there were more tannins in AEB and HLE. In the in vitro tests, the extracts inhibited the phospholipase and fibrinolytic activities of BaV in the two ratios of venom to extract used. HLE exhibited effective antimicrobial action as it inhibited growth of 11 of the 15 bacteria investigated, including Morganella morganii, the main bacteria described in the oral cavity of snakes. The extracts failed to inhibit the defibrinating activity of BaV, and only the Bothrops antivenom had a significant effect (96.1%) on this activity. BaV-induced hemorrhage was completely inhibited by AEL and AEB when the pre-incubation (venom:extract) protocol was used. When administered orally, as in folk medicine, both AEB and AEL produced significant inhibition of hemorrhagic activity (maximum inhibition 46.5% and 39.2%, respectively). SDS-PAGE and WB of the extracts pre-incubated with BaV showed that the main proteins in the venom had been precipitated by the extracts. None of the four extracts showed cytotoxic effects in the tests carried out with a human fibroblast cell line. CONCLUSION: In addition to being effective in reducing hemorrhage when administered orally, the extracts displayed a high antimicrobial potential against microorganisms involved in secondary infections at the site of the snakebite. Once the extracts have been tested in accordance with the appropriate regulations, this species could potentially be used to produce a phytomedicine for complementary treatment of the secondary infections due to bacteria that aggravate the local signs and symptoms after snakebite envenomation.


Subject(s)
Anti-Infective Agents/pharmacology , Antifibrinolytic Agents/pharmacology , Bothrops , Plant Extracts/pharmacology , Plant Extracts/toxicity , Snake Bites/drug therapy , Animals , Anti-Infective Agents/toxicity , Antifibrinolytic Agents/toxicity , Antivenins/pharmacology , Antivenins/toxicity , Cell Survival , Cells, Cultured , Crotalid Venoms/antagonists & inhibitors , Fibrin/antagonists & inhibitors , Hemostatics/pharmacology , Hemostatics/toxicity , Humans , Phenols/analysis , Phospholipases/antagonists & inhibitors , Plant Bark/chemistry , Plant Leaves/chemistry
18.
PLoS One ; 12(12): e0189151, 2017.
Article in English | MEDLINE | ID: mdl-29244816

ABSTRACT

Sensorimotor dysfunction following incomplete spinal cord injury (SCI) is often characterized by paralysis, spasticity and pain. Previously, we showed that intrathecal (i.t.) administration of the albumin-oleic acid (A-OA) complex in rats with SCI produced partial improvement of these symptoms and that oral 2-hydroxyoleic acid (HOA, a non-hydrolyzable OA analogue), was efficacious in the modulation and treatment of nociception and pain-related anxiety, respectively. Here we observed that intrathecal treatment with the complex albumin-HOA (A-HOA) every 3 days following T9 spinal contusion injury improved locomotor function assessed with the Rotarod and inhibited TA noxious reflex activity in Wistar rats. To investigate the mechanism of action of A-HOA, microarray analysis was carried out in the spinal cord lesion area. Representative genes involved in pain and neuroregeneration were selected to validate the changes observed in the microarray analysis by quantitative real-time RT-PCR. Comparison of the expression between healthy rats, SCI rats, and SCI treated with A-HOA rats revealed relevant changes in the expression of genes associated with neuronal morphogenesis and growth, neuronal survival, pain and inflammation. Thus, treatment with A-HOA not only induced a significant overexpression of growth and differentiation factor 10 (GDF10), tenascin C (TNC), aspirin (ASPN) and sushi-repeat-containing X-linked 2 (SRPX2), but also a significant reduction in the expression of prostaglandin E synthase (PTGES) and phospholipases A1 and A2 (PLA1/2). Currently, SCI has very important unmet clinical needs. A-HOA downregulated genes involved with inflammation and upregulated genes involved in neuronal growth, and may serve to promote recovery of function after experimental SCI.


Subject(s)
Albumins/pharmacology , Oleic Acids/pharmacology , Pain/prevention & control , Paralysis/drug therapy , Recovery of Function/drug effects , Spinal Cord Injuries/drug therapy , Albumins/chemistry , Animals , Drug Administration Schedule , Extracellular Matrix Proteins/agonists , Extracellular Matrix Proteins/genetics , Extracellular Matrix Proteins/metabolism , Gene Expression Regulation , Growth Differentiation Factor 10/agonists , Growth Differentiation Factor 10/genetics , Growth Differentiation Factor 10/metabolism , Injections, Spinal , Locomotion/drug effects , Locomotion/physiology , Male , Nerve Tissue Proteins/agonists , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Nociception/drug effects , Oleic Acids/chemistry , Pain/genetics , Pain/metabolism , Pain/pathology , Paralysis/genetics , Paralysis/metabolism , Paralysis/pathology , Phospholipases/antagonists & inhibitors , Phospholipases/genetics , Phospholipases/metabolism , Prostaglandin-E Synthases/antagonists & inhibitors , Prostaglandin-E Synthases/genetics , Prostaglandin-E Synthases/metabolism , Rats , Rats, Wistar , Recovery of Function/physiology , Rotarod Performance Test , Spinal Cord/drug effects , Spinal Cord/metabolism , Spinal Cord/pathology , Spinal Cord Injuries/genetics , Spinal Cord Injuries/metabolism , Spinal Cord Injuries/pathology , Tenascin/agonists , Tenascin/genetics , Tenascin/metabolism , Treatment Outcome
19.
Nat Commun ; 8(1): 1760, 2017 11 24.
Article in English | MEDLINE | ID: mdl-29170371

ABSTRACT

Heteroatom-rich organoboron compounds have attracted attention as modulators of enzyme function. Driven by the unmet need to develop chemoselective access to boron chemotypes, we report herein the synthesis of α- and ß-aminocyano(MIDA)boronates from borylated carbonyl compounds. Activity-based protein profiling of the resulting ß-aminoboronic acids furnishes selective and cell-active inhibitors of the (ox)lipid-metabolizing enzyme α/ß-hydrolase domain 3 (ABHD3). The most potent compound displays nanomolar in vitro and in situ IC50 values and fully inhibits ABHD3 activity in human cells with no detectable cross-reactivity against other serine hydrolases. These findings demonstrate that synthetic methods that enhance the heteroatom diversity of boron-containing molecules within a limited set of scaffolds accelerate the discovery of chemical probes of human enzymes.


Subject(s)
Boron Compounds/chemistry , Enzyme Inhibitors/chemistry , Phospholipases/antagonists & inhibitors , Boron/chemistry , Boron/metabolism , Boron Compounds/chemical synthesis , Boron Compounds/metabolism , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/metabolism , Humans , Molecular Structure , Phospholipases/chemistry , Phospholipases/metabolism , Phospholipases A2
20.
Molecules ; 22(9)2017 Sep 18.
Article in English | MEDLINE | ID: mdl-28926992

ABSTRACT

The native tree Geoffroea decorticans (chañar) grows in the arid lands of northern Chile. It has been used as a food plant since prehistoric times. Phenolic-enriched extracts (PEEs) of Chilean chañar fruits were assessed for their chemical composition, antioxidant properties and inhibition of pro-inflammatory and metabolic syndrome-associated enzymes. Phenolic profiles were determined by HPLC-DAD-MS/MS. The PEEs of G. decorticans showed a strong effect towards the enzymes COX-1/COX-2, with inhibition percentages ranging from inactive to 92.1% and inactive to 76.0% at 50 µg PEE/mL, respectively. The IC50 values of the PEEs towards lipoxygenase and phospholipase A2 inhibitory activity were between 43.6-96.8 and 98.9-156.0 µg PEE/mL, respectively. Samples inhibited α-glucosidase (IC50 0.8-7.3 µg PEE/mL) and lipase (9.9 to >100 µg PEE/mL). However, samples did not inhibit α-amylase. The HPLC-DAD-MS analysis of the PEEs allowed the tentative identification of 53 compounds, mainly flavonol glycosides and procyanidins. The procyanidin content of the Chilean G. decorticans pulp was positively correlated with the antioxidant activity and the inhibition of the enzyme α-glucosidase. These results indicate that the Chilean chañar fruit contains bioactive polyphenols with functional properties.


Subject(s)
Anti-Inflammatory Agents/chemistry , Antioxidants/chemistry , Fabaceae/chemistry , Phenols/chemistry , Anti-Inflammatory Agents/isolation & purification , Anti-Inflammatory Agents/pharmacology , Antioxidants/isolation & purification , Antioxidants/pharmacology , Biflavonoids/chemistry , Catechin/chemistry , Cell Survival/drug effects , Chile , Fibroblasts/cytology , Fibroblasts/drug effects , Flavonols/chemistry , Fruit/chemistry , Humans , Lipoxygenase/metabolism , Metabolic Syndrome/enzymology , Phenols/isolation & purification , Phenols/pharmacology , Phospholipases/antagonists & inhibitors , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Proanthocyanidins/chemistry , alpha-Glucosidases/metabolism
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