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1.
J Tradit Chin Med ; 42(4): 595-603, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35848976

RESUMO

OBJECTIVE: To evaluate Sterculia diversifolia stem bark and leaves for phytotoxic, genotoxic and enzymes inhibition potential. METHODS: Phytotoxic activity of both stem bark and leaves were screened using Lemna minor. The genotoxic activity of Sterculia diversifolia stem bark and leaves extracts were tested using comet assay protocol while enzyme inhibition activity of crude extract and various fractions of both stem bark and leaves were evaluated using acetyl cholinesterase, lipoxygenase, ß-glu-curonidase, urease, xanthine oxidase and carbonic anhydrase. RESULTS: Phytotoxic activity showed significant results in dose dependant manner in both stem bark (ethyl acetate and n-butanol) and leaves (ethyl acetate, n-butanol and n-hexane) fractions. In genotoxic activity, dichloromethane fraction showed significant activity followed by ethyl acetate fraction. Acetyl cholinesterease inhibitory activity showed significant results in both stem bark and leaves fractions, while significant lipoxygenase inhibition was shown by ethyl acetate, dichloromethane, crude extract and n-hexane fractions of both stem bark and leaves. ß-glucuronidase, urease and carbonic anhydrase inhibitory activity showed highly significant results in ethyl acetate fraction of both stem bark and leaves, while xanthine oxidase inhibition was shown by dichloromethane fraction of stem bark and leaves extracts. CONCLUSIONS: This study emphasizes the important phytotoxic, genotoxic and enzyme inhibition effects of Sterculia diversifolia stem bark and leaves. Hence, it is clear that Sterculia diversifolia stem bark and leaves possess phytotoxic, genotoxic and enzyme inhibitory agents.


Assuntos
Alcaloides , Anidrases Carbônicas , 1-Butanol , Dano ao DNA , Humanos , Lipoxigenases , Cloreto de Metileno , Casca de Planta , Extratos Vegetais/toxicidade , Folhas de Planta , Urease , Xantina Oxidase
2.
Molecules ; 27(13)2022 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35807516

RESUMO

Peucedanum ostruthium (L.) W. D. J. Koch (Apiaceae) is a worldwide perennial herb native to the mountains of central Southern Europe. The rhizome has a long tradition in popular medicine, while ethnobotanical surveys have revealed local uses of leaves for superficial injuries. To experimentally validate these uses, plant material was collected in the Gran Paradiso National Park, Aosta Valley, Italy, and the rhizome and leaves were micromorphologically and phytochemically characterized. Polyphenol-enriched hydroalcoholic rhizome and leaf extracts, used in cell-free assays, showed strong and concentration-dependent antioxidant and anti-inflammatory activities. In vitro tests revealed cyclooxygenase and lipoxygenase inhibition by the leaf extract, while the rhizome extract induced only lipoxygenase inhibition. MTT assays on HaCaT keratinocytes and L929 fibroblasts showed low cytotoxicity of extracts. In vitro scratch wound test on HaCaT resulted in a strong induction of wound closure with the leaf extract, while the effect of the rhizome extract was lower. The same test on L929 cells showed similar wound closure induction with both extracts. The results confirmed the traditional medicinal uses of the rhizome as an anti-inflammatory and wound healing remedy for superficial injuries but also highlighted that the leaves can be exploited for these purposes with equal or superior effectiveness.


Assuntos
Apiaceae , Plantas Medicinais , Anti-Inflamatórios/análise , Anti-Inflamatórios/farmacologia , Lipoxigenases , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Folhas de Planta , Plantas Medicinais/química , Rizoma/química , Cicatrização
3.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1867(10): 159205, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35835431

RESUMO

The sequence encoding the CYP5164A3 of the brown alga Ectocarpus siliculosus (Stramenopiles, SAR) was heterologously expressed in E. coli cells. The resulting recombinant CYP74 clan-related protein CYP5164A3 possessed a selective activity towards the α-linolenic acid 13(S)-hydroperoxide (13-HPOTE) and eicosapentaenoic acid 15(S)-hydroperoxide (15-HPEPE). The major products were the heterobicyclic oxylipins. For instance, the 13-HPOTE was converted into plasmodiophorols A, B, and C formed at about 14:3:2 ratio. Plasmodiophorols A-C have been recently described as the products of enzyme hydroperoxide bicyclase CYP50918A1 of cercozoan Plasmodiophora brassicae (Rhizaria, SAR). Furthermore, an unknown compound 1 was detected. Purified product 1 (Me) was identified as a novel substituted 3-propenyl-6-oxabicyclo[3.1.0]hexane based on its MS and NMR spectral data. Conversion of 15-HPEPE by CYP5164A3 resulted in products 7 and 8, analogous to plasmodiophorols A and B. This work uncovered the CYP5164A3 as the first hydroperoxide bicyclase in brown algae. Apparently, this enzyme plays a crucial role in the biosynthesis of heterobicyclic oxylipins like hybridalactone, ecklonilactones, and related natural products, widespread in brown algae.


Assuntos
Oxilipinas , Feófitas , Escherichia coli/metabolismo , Peróxido de Hidrogênio/metabolismo , Lipoxigenases/metabolismo , Oxilipinas/metabolismo , Feófitas/metabolismo , Proteínas Recombinantes/metabolismo
4.
Molecules ; 27(14)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35889376

RESUMO

Lipoxygenases convert polyunsaturated fatty acids into biologically active metabolites such as inflammatory mediators-prostaglandins and leukotrienes. The inhibition of lipoxygenases is increasingly employed in the treatment of cancer. We evaluated the anticancer potential of two novel 5-lipoxygenase inhibitors, named CarbZDNaph and CarbZDChin, which are analogues of the commercially available inhibitor Rev-5901. The in vitro segment of this study was conducted on a mouse colorectal carcinoma cell line-CT26CL25. For an in vivo model, we induced tumors in BALB/c mice by the implantation of CT26CL25 cells, and we treated the animals with potential inhibitors. A 48 h treatment resulted in diminished cell viability. Calculated IC50 values (half-maximal inhibitory concentrations) were 25 µM, 15 µM and 30 µM for CarbZDNaph, CarbZDChin and Rev-5901, respectively. The detailed analysis of mechanism revealed an induction of caspase-dependent apoptosis and autophagy. In the presence of chloroquine, an autophagy inhibitor, we observed an increased mortality of cells, implying a cytoprotective role of autophagy. Our in vivo experiment reports tumor growth attenuation in animals treated with CarbZDChin. Compounds CarbZDNaph and Rev-5901 lacked an in vivo efficacy. The results presented in this study display a strong effect of compound CarbZDChin on malignant cell growth. Having in mind the important role of inflammation in cancer development, these results have a significant impact and are worthy of further evaluation.


Assuntos
Boranos , Carcinoma , Neoplasias do Colo , Animais , Apoptose , Autofagia , Boranos/farmacologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Lipoxigenases , Camundongos , Camundongos Endogâmicos BALB C
5.
Biophys Chem ; 288: 106855, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35849958

RESUMO

Lipoxygenases (LOX) are a family lipid oxygenating enzymes that can generate bioactive lipids of clinical relevance from polyunsaturated fatty acids. Most LOXs display a Ca2+-dependent association with membranes for their activity. Nanodiscs (ND) are stable self-assembled discoidal fragments of lipid bilayers that can mimic the plasma membrane. In this study, we evaluated the association of mammalian 15-LOXs (ALOX15 and ALOX15B) and soybean LOX-1 with NDs (LOX-ND), their enzymatic activities and inhibition. Mammalian LOXs associated with NDs showed better retention of enzymatic function compared to soybean LOX-1. Treatment of both LOX-NDs and free enzymes with the pan-LOX inhibitor nordihydroguaiaretic acid (NDGA) showed an approximately 5-fold more effective inhibition of the enzymes associated with NDs compared to the free form. NDs are easy to generate membrane mimics that can be used as an effective tool to determine enzymatic function and inhibition of membrane associated proteins.


Assuntos
Inibidores de Lipoxigenase , Lipoxigenases , Animais , Inibidores de Lipoxigenase/química , Inibidores de Lipoxigenase/farmacologia , Lipoxigenases/química , Lipoxigenases/metabolismo , Mamíferos/metabolismo , Receptores Depuradores Classe E
6.
Cells ; 11(9)2022 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-35563885

RESUMO

Wheat is vulnerable to numerous diseases; on the other hand, silver nanoparticles (AgNPs) exhibit a sterilizing action. To understand the combined effects of AgNPs with nicotinate and potassium nitrate (KNO3) for plant growth and sterilization, a gel- and label-free proteomics was performed. Root weight was promoted by the treatment of AgNPs mixed with nicotinate and KNO3. From a total of 5557 detected proteins, 90 proteins were changed by the mixture of AgNPs, nicotinate, and KNO3; among them, 25 and 65 proteins increased and decreased, respectively. The changed proteins were mainly associated with redox and biotic stress in the functional categorization. By immunoblot analysis, the abundance of glutathione reductase/peroxiredoxin and pathogen-related protein three significantly decreased with the mixture. Furthermore, from the changed proteins, the abundance of starch synthase and lipoxygenase significantly increased and decreased, respectively. Through biochemical analysis, the starch contents increased with the mixture. The application of esculetin, which is a lipoxygenase inhibitor, increased the weight and length of the root. These results suggest that the AgNPs mixed with nicotinate and KNO3 cause positive effects on wheat seedlings by regulating pathogen-related protein and reactive-oxygen species scavenging. Furthermore, increasing starch and decreasing lipoxygenase might improve wheat growth.


Assuntos
Compostos Inorgânicos , Nanopartículas Metálicas , Niacina , Compostos Inorgânicos/farmacologia , Lipoxigenases , Nanopartículas Metálicas/química , Niacina/farmacologia , Proteômica , Prata/farmacologia , Amido , Triticum
7.
Mar Biotechnol (NY) ; 24(3): 468-479, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35397048

RESUMO

Diatoms produce a variety of oxylipins which are oxygenated polyunsaturated fatty acids and are involved in chemical defense and intercellular communication, among other roles. Although the chemistry of diatom oxylipins has long been studied, the enzymes involved in their production, in particular lipoxygenase (LOX), which catalyzes the initial reaction of the synthesis, have not been discovered in diatom genomes. Recently, diatom LOXs were found in two species, Pseudo-nitzschia arenysensis (PaLOX) and Fragilariopsis cylindrus (FcLOX); however, the enzymology of these LOXs is largely unknown. In this review article, we discuss the potential functions of the diatom LOXs based on previously reported structures of LOXs derived from various organisms other than diatoms. Since the structures of PaLOX and FcLOX have not yet been solved, we discussed their functions, such as regio- and stereospecificities, on the basis of their structures predicted using a computational tool based on deep learning technology. Both diatom LOXs were predicted to conserve common core domains with relatively wide substrate-binding pockets. The stereo-determinant residues in PaLOX and FcLOX suggest S specificity. We assume that the highly conserved common core domain can be a clue to reveal unidentified lox genes from the accumulated diatom genome information with the aid of high-throughput structure prediction tools and structure-based alignment tools in the near future.


Assuntos
Diatomáceas , Diatomáceas/genética , Ácidos Graxos Insaturados , Lipoxigenases , Oxilipinas/química
8.
J Sci Food Agric ; 102(11): 4942-4948, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35275406

RESUMO

BACKGROUND: The presence of secondary metabolites responsible for off-flavours in peas may influence consumers' acceptance. These undesirable compounds may increase due to biotic stress or cultivar. Therefore, grains from two pea (Pisum sativum L.) cultivars (Crécerelle and Firenza) exposed to biotic stress were studied in terms of protein content, electrophoretic polypeptide profile, lipoxygenase activity, saponin content and volatile compounds. RESULTS: No differences were observed in the electrophoretic polypeptide profile of pea samples across cultivar or biotic stress. The cultivar noticeably affected the volatile compounds and lipoxygenase activity. The biotic stress significantly increased the saponin content. CONCLUSION: The cultivar showed more noticeable impact on the presence of off-flavour compounds than the biotic stress. The development of pea protein ingredients needs the thorough choice of raw materials in terms of cultivar and control of biotic stress in order to ensure acceptance by consumers. © 2022 Society of Chemical Industry.


Assuntos
Ervilhas , Saponinas , Lipoxigenases/análise , Lipoxigenases/metabolismo , Ervilhas/química , Saponinas/análise , Sementes/química , Estresse Fisiológico
9.
Int J Mol Sci ; 23(2)2022 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-35054892

RESUMO

Omega-3 and omega-6 fatty acids are important for neonatal development and health. One mechanism by which omega-3 and omega-6 fatty acids exert their effects is through their metabolism into oxylipins and specialized pro-resolving mediators. However, the influence of oxylipins on fetal growth is not well understood. Therefore, the objective of this study was to identify oxylipins present in maternal and umbilical cord plasma and investigate their relationship with infant growth. Liquid chromatography-tandem mass spectrometry was used to quantify oxylipin levels in plasma collected at the time of delivery. Spearman's correlations highlighted significant correlations between metabolite levels and infant growth. They were then adjusted for maternal obesity (normal body mass index (BMI: ≤30 kg/m2) vs. obese BMI (>30 kg/m2) and smoking status (never vs. current/former smoker) using linear regression modeling. A p-value < 0.05 was considered statistically significant. Our study demonstrated a diverse panel of oxylipins from the lipoxygenase pathway present at the time of delivery. In addition, both omega-3 and omega-6 oxylipins demonstrated potential influences on the birth length and weight percentiles. The oxylipins present during pregnancy may influence fetal growth and development, suggesting potential metabolites to be used as biomarkers for infant outcomes.


Assuntos
Lipoxigenases/metabolismo , Obesidade/metabolismo , Oxilipinas/sangue , Cordão Umbilical/metabolismo , Adulto , Cromatografia Líquida , Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Ômega-6/metabolismo , Feminino , Humanos , Recém-Nascido , Obesidade/sangue , Oxilipinas/análise , Oxilipinas/metabolismo , Gravidez , Espectrometria de Massas em Tandem
10.
Food Chem ; 369: 130887, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34461519

RESUMO

Rapid deterioration of rice bran due to the LOX3 enzyme catalysed oxidation of PUFA is the major bottleneck for its utilization in various downstream applications. In the present study, we have identified a set of nine novel LOX3-null rice accessions carrying a deletion of C residue in the exon2 causing a frameshift mutation resulting in a truncated non-functional LOX3 protein. Our study, further manifested the predominance of C deletion based LOX3-null allele, named lox3-b, in the aromatic rice germplasm particularly in the Indian Basmati rice group. The LOX3-null genotypes exhibited significantly reduced rancidity, after six months of storage. They also showed significantly lower percentage reduction of linoleic acid (LA), higher γ-oryzanol content and lower hexanal content. A functional dCAPS marker designed based on the deletion polymorphism clearly differentiated LOX3 and lox3-b alleles, and has the potential application in marker assisted rice breeding programmes to develop cultivars with better bran storability.


Assuntos
Oryza , Alelos , Genótipo , Lipoxigenases , Oryza/genética , Melhoramento Vegetal , Proteínas de Plantas , Polimorfismo Genético
11.
Trends Pharmacol Sci ; 43(3): 188-205, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34961619

RESUMO

Chronic liver diseases (CLDs) caused by viral infections, alcohol/drug abuse, or metabolic disorders affect millions of people globally and have increased mortality owing to the lack of approved therapies. Lipoxygenases (LOXs) are a family of multifaceted enzymes that are responsible for the oxidation of polyunsaturated fatty acids (PUFAs) and are implicated in the pathogenesis of multiple disorders including liver diseases. This review describes the three main LOX signaling pathways - 5-, 12-, and 15-LOX - and their involvement in CLDs. We also provide recent insights and future perspectives on LOX-related hepatic pathophysiology, and discuss the potential of LOXs and LOX-derived metabolites as diagnostic biomarkers and therapeutic targets in CLDs.


Assuntos
Hepatopatias , Doenças Metabólicas , Ácidos Graxos Insaturados , Humanos , Lipoxigenases/metabolismo , Oxirredução
12.
Prostaglandins Other Lipid Mediat ; 158: 106609, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34954219

RESUMO

The arachidonic acid (AA) metabolism pathways play a key role in immunological response and inflammation diseases, such as asthma, etc. AA in cell membranes can be metabolized by lipoxygenases (LOXs) to a screen of bioactive substances that include leukotrienes (LTs), lipoxins (LXs), and eicosatetraenoic acids (ETEs), which are considered closely related to the pathophysiology of respiratory allergic disease. Studies also verified that drugs regulating AA LOXs pathway have better rehabilitative intervention for asthma. This review aims to summarize the physiological and pathophysiological importance of AA LOXs metabolism pathways in asthma and to discuss its prospects of therapeutic strategies.


Assuntos
Asma , Lipoxinas , Araquidonato 5-Lipoxigenase , Araquidonato Lipoxigenases , Asma/tratamento farmacológico , Humanos , Leucotrienos , Lipoxigenases
13.
Zhongguo Zhong Yao Za Zhi ; 46(21): 5665-5673, 2021 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-34951220

RESUMO

The aim of this study was to investigate the mechanism of luteolin regulating lipoxygenase pathway against oxygen-glucose deprivation/reperfusion(OGD/R) injury in H9 c2 cardiomyocytes. First, Discovery Studio 2019 was used for the molecular docking of luteolin with three key enzymes including lipoxygenase 5(ALOX5), lipoxygenase 12(ALOX12), and lipoxygenase 15(ALOX15) in lipoxygenase pathway. The docking results showed that luteolin had high docking score and similar functional groups with the original ligand. From this, H9 c2 cardiomyocytes were cultured in vitro, and then the injury model of H9 c2 cardiomyocytes was induced by deprivation of oxygen-glucose for 8 h, and rehabilitation of oxygen-glucose for 12 h. Cell viability was detected by tetrazolium(MTT) colorimetry. H9 c2 cardiomyocytes were observed with a fluorescence inverted microscope, and colorimetry was used to detect the level of lactate dehydrogenase(LDH) in cell supernatant. The results showed that luteolin could significantly protect the morphology of H9 c2 cells, significantly improve the survival rate of H9 c2 cardiomyocytes in OGD/R injury model, reduce the level of LDH in cell supernatant, inhibit cytotoxicity, and maintain the integrity of cell membrane. The inflammatory cytokines interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α) were detected by enzyme-linked immunosorbent assay. Compared with the model group, luteolin can significantly reduce the release of IL-6 and TNF-α. Western blot was employed to detect the protein levels of ALOX5, ALOX12, and ALOX15 in lipoxygenase pathway. After luteolin intervention, the protein levels of ALOX5, ALOX12, and ALOX15 were significantly down-regulated compared with those in model group. These results indicate that luteolin can inhibit the release of IL-6 and TNF-α by restraining the activation of lipoxygenase pathway, thereby playing a protective role in the cardiomyocyte injury model induced by OGD/R.


Assuntos
Miócitos Cardíacos , Traumatismo por Reperfusão , Apoptose , Glucose , Humanos , Lipoxigenases , Luteolina/farmacologia , Simulação de Acoplamento Molecular , Oxigênio , Transdução de Sinais
14.
Front Endocrinol (Lausanne) ; 12: 706504, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34354672

RESUMO

Background: In previous studies, we reported the beneficial impact of two lipoxygenase-inhibitors, Baicalein and Zileuton, on osteoporotic bone in a postmenopausal rat model. Whereas subcutaneous Baicalein predominantly improved cortical bone, Zileuton enhanced vertebral and femoral trabecular bone. In this study, we aimed to reveal whether the oral administration of Baicalein caused similar effects on bone and whether a combined administration of Baicalein and Zileuton could act synergistically to ameliorate the formerly reported effects in the musculoskeletal system. Methods: We treated ovariectomized (OVX) female Sprague-Dawley rats either with Baicalein (10mg/kg BW), Zileuton (10mg/kg BW) or a combination of both (each 10mg/kg BW) for 13 weeks and compared with untreated OVX and NON-OVX groups (n=12-16 rats per group). Lumbar vertebral bodies and femora were analyzed. Tibiae were osteotomized, plate-stabilized (at week 8 after OVX) and likewise analyzed by biomechanical, histological, micro-computed tomographical and ashing tests. The skeletal muscle structure was analyzed. Results: Oral administration of Baicalein did not confirm the reported favorable cortical effects in neither vertebra nor femur. Zileuton showed a beneficial effect on trabecular vertebra, while the femur was negatively affected. Callus formation was enhanced by all treatments; however, its density and biomechanical properties were unaltered. Lipoxygenase inhibition did not show a beneficial effect on skeletal muscle. The combination therapy did not ameliorate OVX-induced osteoporosis but induced even more bone loss. Conclusions: The preventive anti-osteoporotic treatments with two lipoxygenase inhibitors applied either alone or in combination showed no benefit for the musculoskeletal system in estrogen deficient rats.


Assuntos
Doenças Ósseas Metabólicas/tratamento farmacológico , Estrogênios/deficiência , Inibidores de Lipoxigenase/farmacologia , Lipoxigenases/química , Sistema Musculoesquelético/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Animais , Doenças Ósseas Metabólicas/enzimologia , Doenças Ósseas Metabólicas/etiologia , Doenças Ósseas Metabólicas/patologia , Feminino , Flavanonas/farmacologia , Hidroxiureia/análogos & derivados , Hidroxiureia/farmacologia , Osteoporose/enzimologia , Osteoporose/etiologia , Osteoporose/patologia , Ratos , Ratos Sprague-Dawley
15.
Int J Biol Macromol ; 188: 844-854, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34416264

RESUMO

Lipoxygenase (LOX, EC 1.13.11.12) is a non-haeme iron-containing dioxygenase family that catalyzes the oxygenation of polyunsaturated fatty acids into bio-functionally fatty acid diverse (oxylipins) and plays vital role in plant growth and development and responses to abiotic and biotic stresses. Though LOX genes have been studied in many plant species, their roles in Brassicaceae species are still unknown. Here, a set of 14, 18, and 33 putative LOX genes were identified in Brassica rapa, Brassica oleracea and Brassica napus (allotetraploid rapeseed), respectively, which could be divided into 9-LOX (LOX1/5), 13-LOX type I (LOX3/4/6), and type II (LOX2) subgroups. There was an expansion of LOX2 orthologous genes in Brassicaceae. Most of the LOX genes are intron rich and conserved in gene structure, and the LOX proteins all have the conserved lipoxygenase and PLAT/LH2 domain. Ka/Ks ratio revealed that the majority of LOXs underwent purifying selection in Brassicaceae. The light-, ABA-, MeJA-related cis-elements and MYB-binding sites in the promoters of BnaLOXs were the most abundant. BnaLOXs displayed different spatiotemporal expression patterns and various abiotic/biotic stress responsive expression patterns. BnaLOX1/5 were slightly or no response to phytohormones and abiotic stresses. BnaLOX3/4/6 predominantly express in roots and were strongly up-regulated by salinity and PEG treatments, and BnaLOX3/4 were the methyl jasmonate (MeJA) and salicylic acid (SA) early response genes and strongly induced by infection of Sclerotinia sclerotiorum; while the BnaLOX2 members predominantly express in stamens, were MeJA and SA continuous response genes and strongly repressed by cold, heat and waterlogging treatments in leaves. Our results are useful for understanding the biological functions of the BnaLOX genes in allotetraploid rapeseed.


Assuntos
Brassica napus/enzimologia , Brassica napus/genética , Evolução Molecular , Lipoxigenases/genética , Tetraploidia , Brassica napus/efeitos dos fármacos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Lipoxigenases/metabolismo , Motivos de Nucleotídeos/genética , Filogenia , Reguladores de Crescimento de Plantas/farmacologia , Regiões Promotoras Genéticas/genética , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Sintenia/genética , Temperatura
16.
Prog Lipid Res ; 83: 101110, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34144023

RESUMO

Oxylipins derived mainly from C20- and C22-polyunsaturated fatty acids (PUFAs), termed lipid mediators (LMs), are essential signalling messengers involved in human physiological responses associated with homeostasis and healing process for infection and inflammation. Some LMs involved in the resolution of inflammation and infection are termed specialized pro-resolving mediators (SPMs), which are generated by human M2 macrophages or polymorphonuclear leukocytes and have the potential to protect and treat hosts from bacterial and viral infections by phagocytosis activation. Lipoxygenases (LOXs) biosynthesize regio- and stereoselective LMs. Thus, understanding the regio- and stereoselectivities of LOXs for PUFAs at a molecular level is important for the biocatalytic synthesis of diverse LMs. Here, we elucidate the catalytic mechanisms and discuss regio- and stereoselectivities and their changes of LOXs determined by insertion direction and position of the substrate and oxygen at a molecular level for the biosynthesis of diverse human LMs. Recently, the biocatalytic synthesis of PUFAs to human LMs or analogues has been conducted using microbial LOXs. Such microbial LOXs involved in the biosynthesis of LMs are expected to exert significantly higher activity and stability than human LOXs. Diverse regio- and stereoselective LOXs can be obtained from microorganisms, which represent a wealth of genomic sources. We reconstruct the biosynthetic pathways of LOX-catalyzed LMs in humans and other organisms. Furthermore, we suggest the effective methods of biocatalytic synthesis of diverse human LMs from PUFAs or glucose by using microbial LOXs, increasing the stability and activity of LOXs, combining the reactions of LOXs, and constructing metabolic pathways.


Assuntos
Ácidos Graxos Insaturados , Lipoxigenases , Biocatálise , Humanos , Lipoxigenases/metabolismo
17.
Biochemistry ; 60(22): 1741-1754, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34029049

RESUMO

In this paper, human platelet 12-lipoxygenase [h12-LOX (ALOX12)], human reticulocyte 15-lipoxygenase-1 [h15-LOX-1 (ALOX15)], and human epithelial 15-lipoxygenase-2 [h15-LOX-2 (ALOX15B)] were observed to react with docosahexaenoic acid (DHA) and produce 17S-hydroperoxy-4Z,7Z,10Z,13Z,15E,19Z-docosahexaenoic acid (17S-HpDHA). The kcat/KM values with DHA for h12-LOX, h15-LOX-1, and h15-LOX-2 were 12, 0.35, and 0.43 s-1 µM-1, respectively, which demonstrate h12-LOX as the most efficient of the three. These values are comparable to their counterpart kcat/KM values with arachidonic acid (AA), 14, 0.98, and 0.24 s-1 µM-1, respectively. Comparison of their product profiles with DHA demonstrates that the three LOX isozymes produce 11S-HpDHA, 14S-HpDHA, and 17S-HpDHA, to varying degrees, with 17S-HpDHA being the majority product only for the 15-LOX isozymes. The effective kcat/KM values (kcat/KM × percent product formation) for 17S-HpDHA of the three isozymes indicate that the in vitro value of h12-LOX was 2.8-fold greater than that of h15-LOX-1 and 1.3-fold greater than that of h15-LOX-2. 17S-HpDHA was an effective substrate for h12-LOX and h15-LOX-1, with four products being observed under reducing conditions: protectin DX (PDX), 16S,17S-epoxy-4Z,7Z,10Z,12E,14E,19Z-docosahexaenoic acid (16S,17S-epoxyDHA), the key intermediate in neuroprotection D1 biosynthesis [NPD1, also known as protectin D1 (PD1)], 11,17S-diHDHA, and 16,17S-diHDHA. However, h15-LOX-2 did not react with 17-HpDHA. With respect to their effective kcat/KM values, h12-LOX was markedly less effective than h15-LOX-1 in reacting with 17S-HpDHA, with a 55-fold lower effective kcat/KM in producing 16S,17S-epoxyDHA and a 27-fold lower effective kcat/KM in generating PDX. This is the first direct demonstration of h15-LOX-1 catalyzing this reaction and reveals an in vitro pathway for PDX and NPD1 intermediate biosynthesis. In addition, epoxide formation from 17S-HpDHA and h15-LOX-1 was negatively affected via allosteric regulation by 17S-HpDHA (Kd = 5.9 µM), 12S-hydroxy-5Z,8Z,10E,14Z-eicosatetraenoic acid (12S-HETE) (Kd = 2.5 µM), and 17S-hydroxy-13Z,15E,19Z-docosatrienoic acid (17S-HDTA) (Kd = 1.4 µM), suggesting a possible regulatory pathway in reducing epoxide formation. Finally, 17S-HpDHA and PDX inhibited platelet aggregation, with EC50 values of approximately 1 and 3 µM, respectively. The in vitro results presented here may help advise in vivo PDX and NPD1 intermediate (i.e., 16S,17S-epoxyDHA) biosynthetic investigations and support the benefits of DHA rich diets.


Assuntos
Ácidos Docosa-Hexaenoicos/metabolismo , Lipoxigenases/metabolismo , Regulação Alostérica , Araquidonato 12-Lipoxigenase/metabolismo , Araquidonato 15-Lipoxigenase/metabolismo , Ácido Araquidônico/metabolismo , Ácidos Araquidônicos/metabolismo , Vias Biossintéticas , Plaquetas/metabolismo , Ácidos Docosa-Hexaenoicos/farmacocinética , Ácidos Docosa-Hexaenoicos/farmacologia , Humanos , Lipoxigenase/metabolismo , Lipoxigenases/biossíntese
18.
Sci Rep ; 11(1): 9948, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976263

RESUMO

The LOX genes have been identified and characterized in many plant species, but studies on the banana LOX genes are very limited. In this study, we respectively identified 18 MaLOX, 11 MbLOX, and 12 MiLOX genes from the Musa acuminata, M. balbisiana and M. itinerans genome data, investigated their gene structures and characterized the physicochemical properties of their encoded proteins. Banana LOXs showed a preference for using and ending with G/C and their encoded proteins can be classified into 9-LOX, Type I 13-LOX and Type II 13-LOX subfamilies. The expansion of the MaLOXs might result from the combined actions of genome-wide, tandem, and segmental duplications. However, tandem and segmental duplications contribute to the expansion of MbLOXs. Transcriptome data based gene expression analysis showed that MaLOX1, 4, and 7 were highly expressed in fruit and their expression levels were significantly regulated by ethylene. And 11, 12 and 7 MaLOXs were found to be low temperature-, high temperature-, and Fusarium oxysporum f. sp. Cubense tropical race 4 (FocTR4)-responsive, respectively. MaLOX8, 9 and 13 are responsive to all the three stresses, MaLOX4 and MaLOX12 are high temperature- and FocTR4-responsive; MaLOX6 and MaLOX17 are significantly induced by low temperature and FocTR4; and the expression of MaLOX7 and MaLOX16 are only affected by high temperature. Quantitative real-time PCR (qRT-PCR) analysis revealed that the expression levels of several MaLOXs are regulated by MeJA and FocTR4, indicating that they can increase the resistance of banana by regulating the JA pathway. Additionally, the weighted gene co-expression network analysis (WGCNA) of MaLOXs revealed 3 models respectively for 5 (MaLOX7-11), 3 (MaLOX6, 13, and 17), and 1 (MaLOX12) MaLOX genes. Our findings can provide valuable information for the characterization, evolution, diversity and functionality of MaLOX, MbLOX and MiLOX genes and are helpful for understanding the roles of LOXs in banana growth and development and adaptations to different stresses.


Assuntos
Lipoxigenase/genética , Musa/genética , Frutas/metabolismo , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Estudo de Associação Genômica Ampla/métodos , Lipoxigenase/metabolismo , Lipoxigenases/genética , Lipoxigenases/metabolismo , Doenças das Plantas/genética , Raízes de Plantas/metabolismo , Transcriptoma/genética
19.
Plant Physiol ; 185(4): 1638-1651, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33793947

RESUMO

Drought induces osmotic stress in roots, a condition simulated by the application of high-molecular-weight polyethylene glycol. Osmotic stress results in the reduction of Arabidopsis thaliana root growth and production of 1O2 from an unknown non-photosynthetic source. Reduced root growth can be alleviated by application of the 1O2 scavenger histidine (HIS). Here, we examined the possibility that 1O2 production involves Russell reactions occurring among the enzymatic products of lipoxygenases (LOXs), the fatty acid hydroperoxides. LOX activity was measured for purified soybean (Glycine max) LOX1 and in crude Arabidopsis root extracts using linoleic acid as substrate. Formation of the 13(S)-Hydroperoxy-9(Z),11(E)-octadecadienoic acid product was inhibited by salicylhdroxamic acid, which is a LOX inhibitor, but not by HIS, whereas 1O2 production was inhibited by both. D2O, which specifically extends the half-life of 1O2, augmented the LOX-dependent generation of 1O2, as expected from a Russell-type reaction. The addition of linoleic acid to roots stimulated 1O2 production and inhibited growth, suggesting that the availability of LOX substrate is a rate-limiting step. Indeed, water stress rapidly increased linoleic and linolenic acids by 2.5-fold in roots. Mutants with root-specific microRNA repression of LOXs showed downregulation of LOX protein and activity. The lines with downregulated LOX displayed significantly less 1O2 formation, improved root growth in osmotic stress, and an altered transcriptome response compared with wild type. The results show that LOXs can serve as an enzymatic source of "dark" 1O2 during osmotic stress and demonstrate a role for 1O2 in defining the physiological response.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Lipoxigenases/genética , Lipoxigenases/metabolismo , Raízes de Plantas/metabolismo , Soja/crescimento & desenvolvimento , Soja/metabolismo , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Regulação da Expressão Gênica de Plantas , Variação Genética , Genótipo , Mutação , Osmorregulação/fisiologia , Pressão Osmótica/fisiologia , Raízes de Plantas/genética , Espécies Reativas de Oxigênio
20.
Genes (Basel) ; 12(3)2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33668883

RESUMO

Fusarium verticillioides is one of the most relevant fungal species in maize responsible for ear, stalk and seedling rot, as well as the fumonisin contamination of kernels. Plant lipoxygenases (LOX) synthesize oxylipins that play a crucial role in the regulation of defense mechanisms against pathogens and influence the outcome of pathogenesis. To better uncover the role of these signaling molecules in maize resistance against F. verticillioides, the functional characterization of the 9-LOX gene, ZmLOX4, was carried out in this study by employing mutants carrying Mu insertions in this gene (named as UFMulox4). In this regard, the genotyping of five UFMulox4 identified the mutant UFMu10924 as the only one having an insertion in the coding region of the gene. The impact of ZmLOX4 mutagenesis on kernel defense against F. verticillioides and fumonisin accumulation were investigated, resulting in an increased fungal susceptibility compared to the inbred lines W22 and Tzi18. Moreover, the expression of most of the genes involved in the LOX, jasmonic acid (JA) and green leaf volatiles (GLV) pathways, as well as LOX enzymatic activity, decreased or were unaffected by fungal inoculation in the mutant UFMu10924. These results confirm the strategic role of ZmLOX4 in controlling defense against F. verticillioides and its influence on the expression of several LOX, JA and GLV genes.


Assuntos
Resistência à Doença , Lipoxigenases/genética , Zea mays/genética , Fusarium/patogenicidade , Regulação da Expressão Gênica de Plantas , Mutagênese Insercional , Fenótipo , Proteínas de Plantas/genética , Plântula/genética , Plântula/microbiologia , Análise de Sequência de RNA , Zea mays/microbiologia
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