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1.
Plant Dis ; 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38170445

RESUMO

In June 2021, a disease of stem and leaf rot was observed on lily cultivar 'Tresor' with approximately 20% disease incidence in fields at Huaiyin District (119°04'N, 33°63'E) of Huaian County, Jiangsu Province. The roots and bulbs of symptomatic plants were brown and rotten, with sunken lesions. Symptomatic plants showed short, discolored leaves, and eventually lead to stem wilt and death of the whole plants (Fig. 1A and Fig. 3C). To isolate the pathogen, necrotized plant tissues were surface sterilized with 2% sodium hypochlorite for 2 min followed by 70% ethanol for 30 s and rinsed with sterile water. About 4 mm × 4 mm of diseased tissues were placed on potato dextrose agar (PDA) followed by incubation at 25°C in the dark for 5 days. The pure cultures were obtained by the hyphal-tip method. A total of four fungal isolates with similar colony characteristics were recovered. To determine the identity of the four isolated fungal isolates, genomic DNA was extracted using the method previously described (Khan et al. 2021), the sequences of the internal transcribed spacer (ITS), the translation elongation factor 1α (TEF1) and the RNA polymerase II beta subunit (RPB2) genes were analyzed with primers ITS1/ITS4 (White et al. 1990), EF1/ EF2 (O'Donnell et al. 1998), and 5F2/7cR (Reeb et al. 2004), respectively. The three gene sequences of four isolates showed 99.9 %-100% identities. The531 bp (ITS), 699 bp (TEF1), and 900 bp (RPB2) sequences of a representative isolate (JH-37) were deposited in GenBank with acce. nos. OR195729, OR195041 and OR195040, respectively. A phylogenetic tree was constructed using the concatenated three gene sequences of JH-37 and that of the related Fusarium species based on Maximum Likelihood (Fig.2). JH-37 was grouped together with the F. armeniacum strain CBS 485.94 (AB587001, GQ915501, GQ915485), and shared 99.9 % concatenated sequence identity. The three gene sequences of the strain JH-37 shared 100%, 99.85%, 99.89% identity to F. armeniacum strain CBS 485.94 using MEGA 7 software (Kuma et al. 2016) analysis, and with 94%, 95% and 100% coverage by BLAST analysis. The colony of JH-37 on PDA at 25°C for 5 days was white with yellow-brown pigmentation in the center (Fig. 1B-C). From 10-day-old cultures grown on Spezieller Nahrstoffarmer agar (SNA), macroconidia (n = 50) were falcate, slender, curved dorsiventrally, tapering towards both ends, 3 to 4 septate, and measured 24.2 to 50.0 × 2.6 to 4.2 µm. The microconidia (n = 50) were straight or slightly curved, septate 0 to 2, and measured 6.8 to 20.0× 2.1 to 3.7 µm (Fig.1D-F). These morphological characteristics were consistent with Fusarium spp. (Leslie and Summerell 2006). A pathogenicity test of JH-37 was performed on potted lily ('Tresor') under greenhouse conditions. Healthy lily bulbs were selected and one bulb was sown in soil of each pot. Inoculation was performed 60 days after sowing. Bulbs of the lily plants were wounded with needles and inoculated with 5 mL of conidia suspension (1×107 conidia/mL) in the soil around bulb or an equal amount of sterilized water as a control. This experiment had three replicates. After 15 days of inoculation, typical symptoms of bulb rotten, and leaf wilt, similar to the original field symptoms, appeared on the inoculated plants but not on the controls (Fig.3). The same fungus was reisolated from the diseased plants, as identified based on morphology and molecular evidence, which confirmed the Koch's postulate. To our knowledge, this is the first report that F. armeniacum caused Fusarium wilt on Lilium spp. in China. Further, our result could help to develop effective disease management strategies against lily wilt disease.

2.
Diabetologia ; 66(3): 590-602, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36698021

RESUMO

AIMS/HYPOTHESIS: Accumulating evidence suggests that leucocytes play a critical role in diabetes-induced vascular lesions and other abnormalities that characterise the early stages of diabetic retinopathy. However, the role of monocytes has yet to be fully investigated; therefore, we used Ccr2-/- mice to study the role of CCR2+ inflammatory monocytes in the pathogenesis of diabetes-induced degeneration of retinal capillaries. METHODS: Experimental diabetes was induced in wild-type and Ccr2-/- mice using streptozotocin. After 2 months, superoxide levels, expression of inflammatory genes, leucostasis, leucocyte- and monocyte-mediated cytotoxicity against retinal endothelial cell death, retinal thickness and visual function were evaluated. Retinal capillary degeneration was determined after 8 months of diabetes. Flow cytometry of peripheral blood for differential expression of CCR2 in monocytes was assessed. RESULTS: In nondiabetic mice, CCR2 was highly expressed on monocytes, and Ccr2-/- mice lack CCR2+ monocytes in the peripheral blood. Diabetes-induced retinal superoxide, expression of proinflammatory genes Inos and Icam1, leucostasis and leucocyte-mediated cytotoxicity against retinal endothelial cells were inhibited in diabetic Ccr2-deficient mice and in chimeric mice lacking Ccr2 only from myeloid cells. In order to focus on monocytes, these cells were immuno-isolated after 2 months of diabetes, and they significantly increased monocyte-mediated endothelial cell cytotoxicity ex vivo. Monocytes from Ccr2-deficient mice caused significantly less endothelial cell death. The diabetes-induced retinal capillary degeneration was inhibited in Ccr2-/- mice and in chimeric mice lacking Ccr2 only from myeloid cells. CONCLUSIONS/INTERPRETATION: CCR2+ inflammatory monocytes contribute to the pathogenesis of early lesions of diabetic retinopathy.


Assuntos
Diabetes Mellitus Experimental , Retinopatia Diabética , Degeneração Retiniana , Animais , Camundongos , Retinopatia Diabética/metabolismo , Monócitos/metabolismo , Células Endoteliais/metabolismo , Superóxidos/metabolismo , Degeneração Retiniana/metabolismo , Diabetes Mellitus Experimental/metabolismo , Camundongos Endogâmicos C57BL , Vasos Retinianos/patologia , Receptores CCR2/genética , Receptores CCR2/metabolismo
3.
Int J Mol Sci ; 24(20)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37894985

RESUMO

Lily (Lilium spp.) is a popular ornamental plant. Traditional genetic transformation methods have low efficiency in lily, thus development of a high-efficiency genetic transformation system is important. In this study, a novel transient transformation method involving pollen magnetofection was established and optimized pollen viability, and exogenous gene expression in magnetofected pollen and that of different germplasm were assessed. The highest germination percentage of Lilium regale pollen was 85.73% in medium containing 100 g/L sucrose, 61.5 mg/L H3BO3, and 91.5 mg/L CaCl2. A 1:4 ratio of nanomagnetic beads to DNA plasmid and transformation time of 0.5 h realized the highest transformation efficiency (88.32%). The GFP activity in transformed pollen averaged 69.66%, while that of the control pollen was 0.00%. In contrast to the control, transgenic seedlings obtained by pollination with magnetofected pollen showed strong positive GUS activity with 56.34% transformation efficiency. Among the lily germplasm tested, 'Sweet Surrender' and L. leucanthum had the highest transformation efficiency (85.80% and 54.47%), whereas L. davidii var. willmottiae was not successfully transformed. Transformation efficiency was positively correlated with pollen equatorial diameter and negatively correlated with polar axis/equatorial diameter ratio. The results suggest that pollen magnetofection-mediated transformation can be applied in Lilium but might have species or cultivar specificity.


Assuntos
Lilium , Lilium/genética , Lilium/metabolismo , Pólen/genética , Pólen/metabolismo , Proteínas de Plantas/genética
4.
Diabetologia ; 65(10): 1734-1744, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35852587

RESUMO

AIMS/HYPOTHESIS: Induction of intercellular adhesion molecule-1 (ICAM-1) has been implicated in the development of macrovascular and microvascular diseases such as diabetic retinopathy. Lesions of diabetic retinopathy are unique to the retina but the reason for this is unclear, as all tissues are exposed to the same hyperglycaemic insult. We tested whether diabetes induces ICAM-1 on the luminal surface of endothelial cells to a greater extent in the retina than in other tissues and the role of vision itself in that induction. METHODS: Experimental diabetes was induced in C57Bl/6J, P23H opsin mutant and Gnat1-/- × Gnat2-/- double knockout mice using streptozotocin. The relative abundance of ICAM-1 on the luminal surface of endothelial cells in retina and other tissues was determined by conjugating anti-ICAM-1 antibodies to fluorescent microspheres (2 µm), injecting them intravenously and allowing them to circulate for 30 min. After transcardial perfusion, quantification of microspheres adherent to the endothelium in tissues throughout the body was carried out by fluorescent microscopy or flow cytometry. Mice injected with lipopolysaccharide (LPS) were used as positive controls. The difference in leucostasis between retinal and non-retinal vasculature was evaluated. RESULTS: Diabetes significantly increased ICAM-1-mediated adherence of microspheres to retinal microvessels by almost threefold, independent of sex. In contrast, diabetes had a much smaller effect on endothelial ICAM-1 in other tissues, and more tissues showed a significant induction of endothelial ICAM-1 with LPS than with diabetes. The diabetes-induced increase in endothelial ICAM-1 in retinal vasculature was inhibited by blocking phototransduction in photoreceptor cells. Diabetes significantly increased leucostasis in the retina by threefold compared with a non-ocular tissue (cremaster). CONCLUSIONS/INTERPRETATION: The diabetes-induced upregulation of ICAM-1 on the luminal surface of the vascular endothelium varies considerably among tissues and is highest in the retina. Induction of ICAM-1 on retinal vascular endothelial cells in diabetes is influenced by vision-related processes in photoreceptor cells. The unique presence of photoreceptors in the retina might contribute to the greater susceptibility of this tissue to vascular disease in diabetes.


Assuntos
Diabetes Mellitus Experimental , Retinopatia Diabética , Molécula 1 de Adesão Intercelular/metabolismo , Animais , Células Endoteliais , Lipopolissacarídeos/efeitos adversos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Opsinas , Estreptozocina
5.
Am J Pathol ; 191(10): 1805-1821, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34214506

RESUMO

This study tested the hypothesis that diabetes promotes a greater than normal cytosolic calcium level in rod cells that activates a Ca2+-sensitive protease, calpain, resulting in oxidative stress and inflammation, two pathogenic factors of early diabetic retinopathy. Nondiabetic and 2-month diabetic C57Bl/6J and calpain1 knockout (Capn1-/-) mice were studied; subgroups were treated with a calpain inhibitor (CI). Ca2+ content was measured in photoreceptors using Fura-2. Retinal calpain expression was studied by quantitative RT-PCR and immunohistochemistry. Superoxide and expression of inflammatory proteins were measured using published methods. Proteomic analysis was conducted on photoreceptors isolated from untreated diabetic mice or treated daily with CI for 2 months. Cytosolic Ca2+ content was increased twofold in photoreceptors of diabetic mice as compared with nondiabetic mice. Capn1 expression increased fivefold in photoreceptor outer segments of diabetic mice. Pharmacologic inhibition or genetic deletion of Capn1 significantly suppressed diabetes-induced oxidative stress and expression of proinflammatory proteins in retina. Proteomics identified a protein (WW domain-containing oxidoreductase [WWOX]) whose expression was significantly increased in photoreceptors from mice diabetic for 2 months and was inhibited with CI. Knockdown of Wwox using specific siRNA in vitro inhibited increase in superoxide caused by the high glucose. These results suggest that reducing Ca2+ accumulation, suppressing calpain activation, and/or reducing Wwox up-regulation are novel targets for treating early diabetic retinopathy.


Assuntos
Cálcio/metabolismo , Calpaína/metabolismo , Retinopatia Diabética/patologia , Inflamação/patologia , Estresse Oxidativo , Células Fotorreceptoras/metabolismo , Células Fotorreceptoras/patologia , Animais , Calpaína/genética , Linhagem Celular , Retinopatia Diabética/complicações , Retinopatia Diabética/genética , Retinopatia Diabética/fisiopatologia , Ativação Enzimática/efeitos dos fármacos , Deleção de Genes , Regulação da Expressão Gênica/efeitos dos fármacos , Glicoproteínas/farmacologia , Inflamação/complicações , Inflamação/genética , Inflamação/fisiopatologia , Molécula 1 de Adesão Intercelular/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Proteoma/metabolismo , Retina/patologia , Índice de Gravidade de Doença , Superóxidos/metabolismo , Regulação para Cima/efeitos dos fármacos , Visão Ocular/efeitos dos fármacos , Oxidorredutase com Domínios WW/metabolismo
6.
Antonie Van Leeuwenhoek ; 115(3): 353-364, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35088183

RESUMO

A bacterial strain, designated AETb3-4T was isolated from the rhizosphere of lily. Comparison of 16S rRNA gene sequences showed that the sequence from strain AETb3-4T exhibits high sequence similarity with those of Arthrobacter silviterrae KIS14-16T (97.9%), Arthrobacter livingstonensis LI2T (97.2%) and Arthrobacter stackebrandtii CCM 2783T (97.0%). Whole genome average nucleotide identity (ANI) and the digital DNA-DNA hybridization (dDDH) values between strain AETb3-4T and the reference strains A. silviterrae DSM 27180T, A. livingstonensis L12T and A. stackebrandtii DSM 16005T were below 83.6% and 27.7%, respectively, values which are considerably below the proposed thresholds for the species delineation, consistent with the proposal that strain AETb3-4T represents a novel species. The genome size of strain AETb3-4T is 4.33 Mb and the genomic DNA G + C content is 67.3%. The main polar lipids were identified as phosphatidylglycerol, diphosphatidylglycero, phosphatidylinositol and an unidentified glycolipid. The major fatty acids (> 10%) were identified as anteiso-C15: 0 and anteiso-C17: 0. The predominant menaquinone was found to be menaquinone 9 (MK-9) (H2) (82.2%). Phenotypic tests allowed the strain to be differentiated from its close phylogenetic neighbors. Based on the results obtained, it is proposed that the strain AETb3-4T (= CFCC 16390T = LMG 31708T) represents a novel species in the genus Arthrobacter, for which the names Arthrobacter wenxiniae sp. nov. is proposed. In addition, the novel strain AETb3-4T has multiple plant growth-promoting characters including ACC-deaminase activity and production of IAA. Furthermore, the genome contains secondary metabolite biosynthesis gene clusters, including a carotenoid biosynthetic gene cluster, suggesting potential capacities for secondary metabolite synthesis. These data suggest that strain AETb3-4T may have potential applications both in medicine and sustainable agriculture.


Assuntos
Arthrobacter , Técnicas de Tipagem Bacteriana , Carotenoides , DNA Bacteriano/genética , Ácidos Graxos , Família Multigênica , Hibridização de Ácido Nucleico , Peptidoglicano , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2
7.
Mol Pharmacol ; 100(5): 470-479, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34393108

RESUMO

We compared monotherapies and combinations of therapies that regulate G-protein-coupled receptors (GPCRs) with respect to their abilities to inhibit early stages of diabetic retinopathy (DR) in streptozotocin-diabetic mice. Metoprolol (MTP; 0.04-1.0 mg/kg b.wt./day), bromocriptine (BRM; 0.01-0.1 mg/kg b.wt./day), doxazosin (DOX; 0.01-1.0 mg/kg b.wt./day), or tamsulosin (TAM; 0.05-0.25 mg/kg b.wt./day) were injected individually daily for 2 months in dose-response studies to assess their effects on the diabetes-induced increases in retinal superoxide and leukocyte-mediated cytotoxicity against vascular endothelial cells, both of which abnormalities have been implicated in the development of DR. Each of the individual drugs inhibited the diabetes-induced increase in retinal superoxide at the higher concentrations tested, but the inhibition was lost at lower doses. To determine whether combination therapies had superior effects over individual drugs, we intentionally selected for each drug a low dose that had little or no effect on the diabetes-induced retinal superoxide for use separately or in combinations in 8-month studies of retinal function, vascular permeability, and capillary degeneration in diabetes. At the low doses used, combinations of the drugs generally were more effective than individual drugs, but the low-dose MTP alone totally inhibited diabetes-induced reduction in a vision task, BRM or DOX alone totally inhibited the vascular permeability defect, and DOX alone totally inhibited diabetes-induced degeneration of retinal capillaries. Although low-dose MTP, BRM, DOX, or TAM individually had beneficial effects on some endpoints, combination of the therapies better inhibited the spectrum of DR lesions evaluated. SIGNIFICANCE STATEMENT: The pathogenesis of early stages of diabetic retinopathy remains incompletely understood, but multiple different cell types are believed to be involved in the pathogenic process. We have compared the effects of monotherapies to those of combinations of drugs that regulate GPCR signaling pathways with respect to their relative abilities to inhibit the development of early diabetic retinopathy.


Assuntos
Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/metabolismo , Hipoglicemiantes/administração & dosagem , Receptores Adrenérgicos/metabolismo , Receptores Dopaminérgicos/metabolismo , Receptores de Serotonina/metabolismo , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Retinopatia Diabética/patologia , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Vasos Retinianos/efeitos dos fármacos , Vasos Retinianos/metabolismo , Vasos Retinianos/patologia
8.
BMC Plant Biol ; 21(1): 465, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34645404

RESUMO

BACKGROUND: Lilium is an important ornamental bulb, possesses medicinal properties, and is also edible. Species within the Lilium genus share very similar morphology and macroscopic characteristics, thus they cannot be easily and clearly distinguished from one another. To date, no efficient species-specific markers have been developed for classifying wild lily species, which poses an issue with further characterizing its medicinal properties. RESULTS: To develop a simple and reliable identification system for Lilium, 45 representative species from 6 sections were used to develop a DNA barcoding system, which was based on DNA sequence polymorphisms. In this study, we assessed five commonly used DNA barcode candidates (ITS, rbcL, ycf1b, matK and psbA-trnH) and five novel barcode candidates obtained from highly variable chloroplast genomic regions (trnL-trnF, trnS-trnG, trnF-ndhJ, trnP-psaJ-rpI33 and psbB-psbH). We showed that a set of three novel DNA barcodes (ITS + trnP-psaJ-rpI33 + psbB-psbH) could be efficiently used as a genetic marker to distinguish between lily species, as assessed by methods including DNAsp, BI and ML tree, and Pair Wise Group (PWG). CONCLUSIONS: A rapid and reliable DNA barcoding method was developed for all 45 wild Lilium species by using ITS, trnP-psaJ-rpI33, and psbB-psbH as DNA barcoding markers. The method can be used in the classification of wild Lilium species, especially endangered species, and also provides an effective method for selective lily breeding.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Espécies em Perigo de Extinção , Marcadores Genéticos , Genoma de Cloroplastos , Lilium/classificação , Lilium/genética , Plantas Medicinais/genética , Análise de Sequência de DNA , Variação Genética , Filogenia , Especificidade da Espécie
9.
Antonie Van Leeuwenhoek ; 114(8): 1213-1224, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34002321

RESUMO

A novel Gram-stain-negative, aerobic and rod-shaped bacterium with a single polar flagellum or a stalk at the end of the cell, was isolated from maize roots in the Fangshan District of Beijing, People's Republic of China. The new strain designated 774T produced indole acetic acid (IAA). The 16S rRNA gene sequence analysis indicated that strain 774T belongs to the genus Caulobacter and is closely related to Caulobacter flavus RHGG3T, Caulobacter zeae 410Tand Caulobacter radices 695T, all with sequence similarities of 99.9%. The genome size of strain774T was 5.4 Mb, comprising 5042 predicted genes with a DNA G+C content of 68.7%.Three striking lasso peptide biosynthetic gene clusters and two IAA synthesis genes belonging to the TPM pathway were also found in the genome of strain 774T. The average nucleotide identity values and digital DNA-DNA hybridization values of the strain774T with its closely phylogenetic neighbours were less than 91.5% and 45.0%, respectively, indicating a new Caulobacter species. The major fatty acids of strain774T were identified as C16: 0 (27.7%), summed feature 3 (C16: 1ω6c and/or C16: 1ω7c) (12.6%) and summed feature 8 (C18: 1ω7c and/or C18: 1ω6c) (42.9%).The major polar lipids consisted of phosphatidyl-glycerol and glycolipids. The predominant ubiquinone was identified as Quinone 10. Based on the polyphasic characterization, strain 774T represents a novel species of the genus Caulobacter, for which the name Caulobacter endophyticus sp. nov. is proposed with 774T (= CGMCC 1.16558T = DSM 106777T) as the type strain.


Assuntos
Caulobacter , Zea mays , Técnicas de Tipagem Bacteriana , Caulobacter/genética , DNA Bacteriano/genética , Ácidos Graxos/análise , Humanos , Ácidos Indolacéticos , Família Multigênica , Peptídeos , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Microbiologia do Solo , Ubiquinona
10.
Plant Cell Rep ; 40(10): 1889-1906, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34259890

RESUMO

KEY MESSAGE: A number of potential genes and pathways involved in tepal trichome development were identified in a natural lily mutant by transcriptome analysis and were confirmed with trichome and trichomeless species. Trichome is a specialized structure found on the surface of the plant with an important function in survival against abiotic and biotic stress. It is also an important economic trait in crop breeding. Extensive research has investigated the foliar trichome in model plants (Arabidopsis and tomato). However, the developmental mechanism of tepal trichome remains elusive. Lilium pumilum is an edible ornamental bulb and a good breeding parent possessing cold and salt-alkali resistance. Here, we found a natural mutant of Lilium pumilum grown on a highland whose tepals are covered by trichomes. Our data indicate that trichomes of the mutant are multicellular and branchless. Notably, stomata are also developed on the tepal of the mutant as well, suggesting there may be a correlation between trichome and stomata regulation. Furthermore, we isolated 27 differentially expressed genes (DEGs) by comparing the transcriptome profiling between the natural mutant and the wild type. These 27 genes belong to 4 groups: epidermal cell cycle and division, trichome morphogenesis, stress response, and transcription factors. Quantitative real-time PCR in Lilium pumilum (natural mutant and the wild type) and other lily species (Lilium leichtlinii var. maximowiczii/trichome; Lilium davidii var. willmottiae/, trichomeless) confirmed the validation of RNA-seq data and identified several trichome-related genes.


Assuntos
Lilium/genética , Tricomas/citologia , Tricomas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Lilium/citologia , Lilium/crescimento & desenvolvimento , Microscopia Eletrônica de Transmissão , Mutação , Células Vegetais , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Reprodutibilidade dos Testes , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Tricomas/crescimento & desenvolvimento
12.
J Biol Chem ; 290(35): 21568-79, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26139608

RESUMO

Recent evidence suggests an important role for outer retinal cells in the pathogenesis of diabetic retinopathy (DR). Here we investigated the effect of the visual cycle inhibitor retinylamine (Ret-NH2) on the development of early DR lesions. Wild-type (WT) C57BL/6J mice (male, 2 months old when diabetes was induced) were made diabetic with streptozotocin, and some were given Ret-NH2 once per week. Lecithin-retinol acyltransferase (LRAT)-deficient mice and P23H mutant mice were similarly studied. Mice were euthanized after 2 (WT and Lrat(-/-)) and 8 months (WT) of study to assess vascular histopathology, accumulation of albumin, visual function, and biochemical and physiological abnormalities in the retina. Non-retinal effects of Ret-NH2 were examined in leukocytes treated in vivo. Superoxide generation and expression of inflammatory proteins were significantly increased in retinas of mice diabetic for 2 or 8 months, and the number of degenerate retinal capillaries and accumulation of albumin in neural retina were significantly increased in mice diabetic for 8 months compared with nondiabetic controls. Administration of Ret-NH2 once per week inhibited capillary degeneration and accumulation of albumin in the neural retina, significantly reducing diabetes-induced retinal superoxide and expression of inflammatory proteins. Superoxide generation also was suppressed in Lrat(-/-) diabetic mice. Leukocytes isolated from diabetic mice treated with Ret-NH2 caused significantly less cytotoxicity to retinal endothelial cells ex vivo than did leukocytes from control diabetics. Administration of Ret-NH2 once per week significantly inhibited the pathogenesis of lesions characteristic of early DR in diabetic mice. The visual cycle constitutes a novel target for inhibition of DR.


Assuntos
Retinopatia Diabética/tratamento farmacológico , Diterpenos/uso terapêutico , Aciltransferases/deficiência , Aciltransferases/metabolismo , Animais , Separação Celular , Retinopatia Diabética/sangue , Retinopatia Diabética/patologia , Retinopatia Diabética/fisiopatologia , Diterpenos/administração & dosagem , Diterpenos/química , Diterpenos/farmacologia , Relação Dose-Resposta a Droga , Células Endoteliais/metabolismo , Glucose/metabolismo , Inflamação/patologia , Leucócitos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Permeabilidade , Células Fotorreceptoras de Vertebrados/metabolismo , Retina/efeitos dos fármacos , Retina/patologia , Retina/fisiopatologia , Superóxidos/metabolismo
13.
FASEB J ; 29(5): 2194-204, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25667222

RESUMO

Reactive oxygen species play an important role in the pathogenesis of diabetic retinopathy. We studied the role of adrenergic and serotonin receptors in the generation of superoxide by retina and 661W retinal cells in high glucose and of the α1-adrenergic receptor (AR) on vascular lesions of the retinopathy in experimentally diabetic C57Bl/6J mice (and controls) after 2 and 8 months. Compared with 5 mM glucose, incubating cells or retinal explants in 30 mM glucose induced superoxide generation. This response was reduced or ablated by pharmacologic inhibition of the α1-AR (a Gq-coupled receptor) or Gs-coupled serotonin (5-HT2, 5-HT4, 5-HT6, and 5-HT7) receptors or by activation of the Gi-coupled α2-AR. In elevated glucose, the α1-AR produced superoxide via phospholipase C, inositol triphosphate-induced Ca(2+) release, and NADPH oxidase, and pharmacologic inhibition of these reactions prevented the superoxide increase. Generation of retinal superoxide, expression of proinflammatory proteins, and degeneration of retinal capillaries in diabetes all were significantly inhibited with daily doxazosin or apocynin (inhibitors of α1-AR and NADPH oxidase, respectively), but increased vascular permeability was not significantly affected. Adrenergic receptors, and perhaps other GPCRs, represent novel targets for inhibiting the development of important features of diabetic retinopathy.


Assuntos
Capilares/patologia , Diabetes Mellitus Experimental/complicações , Retinopatia Diabética/patologia , Receptores Adrenérgicos/metabolismo , Receptores de Serotonina/metabolismo , Degeneração Retiniana/patologia , Superóxidos/metabolismo , Animais , Capilares/metabolismo , Células Cultivadas , AMP Cíclico/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Retinopatia Diabética/etiologia , Retinopatia Diabética/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores Adrenérgicos/genética , Receptores de Serotonina/genética , Retina/citologia , Retina/metabolismo , Degeneração Retiniana/etiologia , Degeneração Retiniana/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
Proc Natl Acad Sci U S A ; 110(41): 16586-91, 2013 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-24067647

RESUMO

Accumulating evidence suggests that photoreceptor cells play a previously unappreciated role in the development of early stages of diabetic retinopathy, but the mechanism by which this occurs is not clear. Inhibition of oxidative stress is known to inhibit the vascular lesions of early diabetic retinopathy, and we investigated whether the diabetes-induced oxidative stress in the retina emanates from photoreceptors. Superoxide generation was assessed in retinas of male C57BL/6J mice made diabetic for 2 mo (4 mo of age when killed) using histochemical (dichlorofluorescein and dihydroethidine) and bioluminescence (lucigenin) methods. Photoreceptors were eliminated in vivo by genetic (opsin(-/-)) and chemical (iodoacetic acid) techniques. Immunoblots were used to measure expression of intercellular adhesion molecule 1 and the inducible form of nitric oxide synthase. Diabetes increased the generation of superoxide by diabetic mouse retina more at night than during the day. Photoreceptors were the major source of reactive oxygen species in the retina, and their deletion (either genetically in opsin(-/-) mice or acutely with iodoacetic acid) inhibited the expected diabetes-induced increase in superoxide and inflammatory proteins in the remaining retina. Both mitochondria and NADPH oxidase contributed to the observed retinal superoxide generation, which could be inhibited in vivo with either methylene blue or apocynin. Photoreceptors are the major source of superoxide generated by retinas of diabetic mice. Pharmaceuticals targeting photoreceptor oxidative stress could offer a unique therapy for diabetic retinopathy.


Assuntos
Diabetes Mellitus Experimental/complicações , Retinopatia Diabética/fisiopatologia , Estresse Oxidativo/fisiologia , Células Fotorreceptoras de Vertebrados/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Retina/patologia , Acridinas , Análise de Variância , Animais , Retinopatia Diabética/etiologia , Feminino , Técnicas Histológicas , Immunoblotting , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência
15.
Diabetologia ; 57(1): 204-13, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24186494

RESUMO

AIMS/HYPOTHESIS: Although much is known about the pathophysiological processes contributing to diabetic retinopathy (DR), the role of protective pathways has received less attention. The transcription factor nuclear factor erythroid-2-related factor 2 (also known as NFE2L2 or NRF2) is an important regulator of oxidative stress and also has anti-inflammatory effects. The objective of this study was to explore the potential role of NRF2 as a protective mechanism in DR. METHODS: Retinal expression of NRF2 was investigated in human donor and mouse eyes by immunohistochemistry. The effect of NRF2 modulation on oxidative stress was studied in the human Müller cell line MIO-M1. Non-diabetic and streptozotocin-induced diabetic wild-type and Nrf2 knockout mice were evaluated for multiple DR endpoints. RESULTS: NRF2 was expressed prominently in Müller glial cells and astrocytes in both human and mouse retinas. In cultured MIO-M1 cells, NRF2 inhibition significantly decreased antioxidant gene expression and exacerbated tert-butyl hydroperoxide- and hydrogen peroxide-induced oxidative stress. NRF2 activation strongly increased NRF2 target gene expression and suppressed oxidant-induced reactive oxygen species. Diabetic mice exhibited retinal NRF2 activation, indicated by nuclear translocation. Superoxide levels were significantly increased by diabetes in Nrf2 knockout mice as compared with wild-type mice. Diabetic Nrf2 knockout mice exhibited a reduction in retinal glutathione and an increase in TNF-α protein compared with wild-type mice. Nrf2 knockout mice exhibited early onset of blood-retina barrier dysfunction and exacerbation of neuronal dysfunction in diabetes. CONCLUSIONS/INTERPRETATION: These results indicate that NRF2 is an important protective factor regulating the progression of DR and suggest enhancement of the NRF2 pathway as a potential therapeutic strategy.


Assuntos
Retinopatia Diabética/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Linhagem Celular , Retinopatia Diabética/genética , Humanos , Masculino , Camundongos , Camundongos Mutantes , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo/genética , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Retina/metabolismo , Retina/patologia
16.
J Plant Res ; 127(2): 249-63, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24212402

RESUMO

We present a comprehensive phylogeny derived from nuclear ribosomal DNA (nrDNA) for 214 samples representing 98 species and five varieties, including 44 species and five varieties native to China. Our collection of 25 species and five varieties (44 samples) covering all five sections of the genus (Comber) distributed in China also were included in the internal transcribed spacer (ITS) database. This study incorporates previous research with an emphasis on Chinese species, including the controversial subsection, Sinomartagon 5c Comber. In the phylogenetic tree obtained by maximum parsimony (PAUP) and maximum likelihood (RAxML) analyses, the samples were divided into four major groups. Our results suggest that the subsection (subsect.) 5c Comber should be classified into the true subsect. 5c and the section (sect.) Lophophorum. And the latter was divided into three subsections (subsect. Lophophorum I, subsect. Lophophorum II, and subsect. Lophophorum III). Based on molecular phylogenetic analysis and fluorescence in situ hybridization, we report that L. henryi and L. rosthornii are closely related, and we propose their classification into subsect. Leucolirion 6a. Our results support Comber's subdivision of sect. Leucolirion, which was primarily based on bulb color. Chinese species were divided into five sections: sect. Martagon, sect. Archelirion, sect. Leucolirion, sect. Sinomartagon, and sect. Lophophorum. These findings contribute to our understanding of the phylogeny, origin, and classification of Lilium.


Assuntos
Variação Genética , Lilium/classificação , Lilium/genética , Sequência de Bases , China , DNA de Plantas/química , DNA de Plantas/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Hibridização in Situ Fluorescente , Lilium/citologia , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie
17.
Mol Neurobiol ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877366

RESUMO

Intracerebral hemorrhage (ICH) is a common cerebrovascular disease that can lead to severe neurological dysfunction in surviving patients, resulting in a heavy burden on patients and their families. When ICH occurs, the blood‒brain barrier is disrupted, thereby promoting immune cell migration into damaged brain tissue. As important immunosuppressive T cells, regulatory T (Treg) cells are involved in the maintenance of immune homeostasis and the suppression of immune responses after ICH. Treg cells mitigate brain tissue damage after ICH in a variety of ways, such as inhibiting the neuroinflammatory response, protecting against blood‒brain barrier damage, reducing oxidative stress damage and promoting nerve repair. In this review, we discuss the changes in Treg cells in ICH clinical patients and experimental animals, the mechanisms by which Treg cells regulate ICH and treatments targeting Treg cells in ICH, aiming to support new therapeutic strategies for clinical treatment.

18.
Sci Rep ; 14(1): 1545, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233457

RESUMO

Dynamic miRNA detection using the qRT-PCR technique requires appropriate reference genes to ensure data reliability. Previous studies have screened internal reference genes in plants during embryonic development and various stress treatment, involving relatively few tissues and organs. There is no relevant miRNA study in Lilium henryi Baker and limited research on the optimal miRNA reference genes in lilies, such as 5S, 18S, U6 and Actin. Twelve genes were selected as candidate reference genes whose expression stability was analyzed in petals at different developmental stages and other tissues using various algorithms, such as geNorm, NormFinder, BestKeeper, and Delta CT. The results revealed that the optimal combination of reference genes for Lilium henryi Baker petals at different developmental stages was osa-miR166m and osa-miR166a-3p, while that for different tissues of Lilium henryi Baker was osa-miR166g-3p and osa-miR166a-3p.Four important genes related to growth and development regulation, namely, osa-miR156a, osa-miR395b, osa-miR396a-3p, and osa-miR396a-5p, were selected for validation. The findings of the present study could contribute to future investigations onmiRNA expression and the related functions in Lilium henryi Baker while providing important references for the normalization of the miRNA expression in other varieties of lily.


Assuntos
Lilium , MicroRNAs , Feminino , Gravidez , Humanos , Lilium/genética , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase em Tempo Real , MicroRNAs/genética , Actinas/genética , Padrões de Referência , Perfilação da Expressão Gênica
19.
Front Neurol ; 15: 1402129, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38938782

RESUMO

Objective: There is currently a lack of evidence in evidence-based medicine regarding acupuncture treatment for experimental intracerebral hemorrhage (ICH). The aim of this study was to systematically evaluate the efficacy of acupuncture treatment for experimental ICH based on neurological function scores and brain water content (BWC). Methods: Eight mainstream Chinese and English databases were searched. Outcome measures included neurological function scores and BWC, and subgroup analysis was conducted based on study characteristics. Results: A total of 32 studies were included. Meta-analysis results indicated that compared to the control group, the acupuncture group showed significant reductions in mNSS (MD = -3.16, p < 0.00001), Bederson score (MD = -0.99, p < 0.00001), Longa score (MD = -0.54, p < 0.0001), and brain water content (MD = -5.39, p < 0.00001). Subgroup analysis revealed that for mNSS, the autologous blood model (MD = -3.36) yielded better results than the collagenase model (MD = -0.92, p < 0.00001), and simple fixation (MD = -3.38) or no fixation (MD = -3.39) was superior to sham acupuncture (MD = -0.92, p < 0.00001). For BWC, the autologous blood model (MD = -7.73) outperformed the collagenase model (MD = -2.76, p < 0.00001), and GV20-GB7 (MD = -7.27) was more effective than other acupuncture points (MD = -2.92, p = 0.0006). Conclusion: Acupuncture significantly improves neurological deficits and brain edema in experimental ICH. Acupuncture at GV20 - GB7 is more effective than at other points. These findings support further studies to translate acupuncture into clinical treatment for human ICH. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023435584.

20.
Diabetes ; 73(2): 280-291, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37986627

RESUMO

Vascular inflammation is known to cause degeneration of retinal capillaries in early diabetic retinopathy (DR), a major microvascular complication of diabetes. Past studies investigating these diabetes-induced retinal vascular abnormalities have focused primarily on the role of molecular or biochemical cues. Here we show that retinal vascular inflammation and degeneration in diabetes are also mechanically regulated by the increase in retinal vascular stiffness caused by overexpression of the collagen-cross-linking enzyme lysyl oxidase (LOX). Treatment of diabetic mice with LOX inhibitor ß-aminopropionitrile (BAPN) prevented the increase in retinal capillary stiffness, vascular intracellular adhesion molecule-1 overexpression, and leukostasis. Consistent with these anti-inflammatory effects, BAPN treatment of diabetic mice blocked the upregulation of proapoptotic caspase-3 in retinal vessels, which concomitantly reduced retinal capillary degeneration, pericyte ghost formation, and the diabetes-induced loss of contrast sensitivity in these mice. Finally, our in vitro studies indicate that retinal capillary stiffening is sufficient to increase the adhesiveness and neutrophil elastase-induced death of retinal endothelial cells. By uncovering a link between LOX-dependent capillary stiffening and the development of retinal vascular and functional defects in diabetes, these findings offer a new insight into DR pathogenesis that has important translational potential.


Assuntos
Diabetes Mellitus Experimental , Retinopatia Diabética , Degeneração Retiniana , Camundongos , Animais , Células Endoteliais , Diabetes Mellitus Experimental/complicações , Aminopropionitrilo/farmacologia , Retina/patologia , Retinopatia Diabética/patologia , Inflamação/patologia , Vasos Retinianos/patologia , Camundongos Endogâmicos C57BL
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