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1.
J Fam Psychol ; 37(8): 1159-1168, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37561501

RESUMO

The present study investigated the intergenerational transmission of anxiety from both mothers and fathers to children in Chinese migrant families and the mediating roles of both parents' harsh discipline (psychological aggression and corporal punishment). Four hundred seventy nine intact families with at least one migrant child were followed prospectively, with data collected from multiple informants at three time points half a year apart. A longitudinal multiple mediation model in combination with an actor-partner interdependent model (APIM) was used to examine the mediating roles of both parents' harsh discipline in the intergenerational transmission of anxiety. Results indicated that anxiety was transmitted across generations from mothers (but not fathers) to migrant children. Significant actor effects of mothers' and fathers' anxiety on their own harsh discipline were found, while no significant partner effects were observed. Mothers' psychological aggression played an important role in the intergenerational transmission of anxiety from mothers to migrant children. The findings suggest that interventions and prevention efforts focusing on reduction of children's anxiety would benefit from decreasing mothers' anxiety and psychological aggression. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Pai , Pais , Masculino , Feminino , Criança , Humanos , Pai/psicologia , Pais/psicologia , Mães/psicologia , Ansiedade , China , Poder Familiar/psicologia
2.
Mol Plant Pathol ; 24(10): 1256-1272, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37357820

RESUMO

Magnaporthe oryzae is a pathogenic fungus that seriously harms rice production. Phosphatases and carbon metabolism play crucial roles in the growth and development of eukaryotes. However, it remains unclear how serine/threonine phosphatases regulate the catabolism of triglycerides, a major form of stored lipids. In this study, we identified a serine/threonine protein phosphatase regulatory subunit, Smek1, which is required for the growth, conidiation, and virulence of M. oryzae. Deletion of SMEK1 led to defects in the utilization of lipids, arabinose, glycerol, and ethanol. In glucose medium, the expression of genes involved in lipolysis, long-chain fatty acid degradation, ß-oxidation, and the glyoxylate cycle increased in the Δsmek1 mutant, which is consistent with ΔcreA in which a carbon catabolite repressor CREA was deleted. In lipid medium, the expression of genes involved in long-chain fatty acid degradation, ß-oxidation, the glyoxylate cycle, and utilization of arabinose, ethanol, or glycerol decreased in the Δsmek1 mutant, which is consistent with Δcrf1 in which a transcription activator CRF1 required for carbon metabolism was deleted. Lipase activity, however, increased in the Δsmek1 mutant in both glucose and lipid media. Moreover, Smek1 directly interacted with CreA and Crf1, and dephosphorylated CreA and Crf1 in vivo. The phosphatase Smek1 is therefore a dual-function regulator of the lipid and carbohydrate metabolism, and controls fungal development and virulence by coordinating the functions of CreA and Crf1 in carbon catabolite repression (CCR) and derepression (CCDR).


Assuntos
Magnaporthe , Oryza , Lipólise , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Arabinose , Glicerol , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/metabolismo , Carbono/metabolismo , Glucose/metabolismo , Glioxilatos , Ácidos Graxos , Treonina/genética , Treonina/metabolismo , Lipídeos , Serina/metabolismo , Regulação Fúngica da Expressão Gênica , Oryza/microbiologia , Doenças das Plantas/microbiologia , Esporos Fúngicos
3.
Front Plant Sci ; 13: 955254, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36160954

RESUMO

The rice blast fungus Magnaporthe oryzae spores differentiate and mature into functional appressoria by sensing the host surface signals. Environmental stimuli are transduced into cells through internalization during appressorium formation, such as in the cAMP-PKA pathway. Here, we describe a novel contribution to how appressoria mature on the surface of a leaf, and its connection to endosomes and the cAMP-PKA pathway. An appressorium membrane-specific protein, Pams1, is required for maintaining endosomal structure, appressorium maturation, and virulence in M. oryzae. During appressorium development, Pams1 was translocated from the cell membrane to the endosomal membrane. Deletion of PAMS1 led to the formation of two types of abnormal appressoria after 8 h post inoculation (hpi): melanized type I had a reduced virulence, while pale type II was dead. Before 8 hpi, Δpams1 formed appressoria that were similar to those of the wild type. After 8 hpi, the appressoria of Δpams1 was differentiated into two types: (1) the cell walls of type I appressoria were melanized, endosomes were larger, and had a different distribution from the wild type and (2) Type II appressoria gradually stopped melanization and began to die. The organelles, including the nucleus, endosomes, mitochondria, and endoplasmic reticula, were degraded, leaving only autophagic body-like vesicles in type II appressoria. The addition of exogenous cAMP to Δpams1 led to the formation of a greater proportion of type I appressoria and a smaller proportion of type II appressoria. Thus, defects in endosomal structure and the cAMP-PKA pathway are among the causes of the defective appressorium maturation and virulence of Δpams1.

4.
Microbiol Spectr ; 10(5): e0102122, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36036638

RESUMO

Rice blast disease caused by Magnaporthe oryzae is a serious threat to global grain yield and food security. Cti6 is a nuclear protein containing a plant homeodomain (PHD) that is involved in transcriptional regulation in Saccharomyces cerevisiae. The biological function of its homologous protein in M. oryzae has been elusive. Here, we report Clp1 with a PHD domain in M. oryzae, a homologous protein of the yeast Cti6. Clp1 was mainly located in the nucleus and partly in the vesicles. Clp1 colocalized and interacted with the autophagy-related proteins Atg5, Atg7, Atg16, Atg24, and Atg28 at preautophagosomal structures (PAS) and autophagosomes, and the loss of Clp1 increased the fungal background autophagy level. Δclp1 displayed reduced hyphal growth and hyperbranching, abnormal fungal morphology (including colony, spore, and appressorium), hindered appressorial glycogen metabolism and turgor production, weakened plant infection, and decreased virulence. The PHD is indispensable for the function of Clp1. Therefore, this study revealed that Clp1 regulates development and pathogenicity by maintaining autophagy homeostasis and affecting gene transcription in M. oryzae. IMPORTANCE The fungal pathogen Magnaporthe oryzae causes serious diseases of grasses such as rice and wheat. Autophagy plays an indispensable role in the pathogenic process of M. oryzae. Here, we report a Cti6-like protein, Clp1, that is involved in fungal development and infection of plants through controlling autophagy homeostasis in the cytoplasm and gene transcription in the nucleus in M. oryzae. This study will help us to understand an elaborated molecular mechanism of autophagy, gene transcription, and virulence in the rice blast fungus.


Assuntos
Magnaporthe , Oryza , Magnaporthe/genética , Magnaporthe/metabolismo , Virulência , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação Fúngica da Expressão Gênica , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Doenças das Plantas/microbiologia , Oryza/genética , Oryza/metabolismo , Oryza/microbiologia , Autofagia , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Proteínas Nucleares/metabolismo , Homeostase , Glicogênio/metabolismo , Esporos Fúngicos
5.
Microbiol Res ; 263: 127141, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35931004

RESUMO

Magnaporthe oryzae infects rice, wheat and other grass crops through appressoria. The formation of the appressorium is regulated by the external environment, signal transduction pathways, and transcription factors. Transcription factors Vrf1 and Hox7 are involved in the regulation of appressorium formation. In this study, we demonstrate that Vrf1 and Hox7 play vital roles in coordinately regulating appressorium maturation. In strain 70-15, deletion of VRF1 resulted in the inability to continue melanization and maturation of the incipient appressorium, and deletion of HOX7 also resulted in defects in appressorium melanization and maturation. The defects in appressorium formation in Δhox7Δvrf1 were similar to those in Δhox7 and Δvrf1. The gene expression profiles of the incipient appressoria at 5 h post-inoculation (hpi) showed that the expression levels of 704 genes (25.94 % of all differentially expressed genes in the three mutants) were significantly downregulated (606 genes) or upregulated (98 genes). In the appressoria of Δhox7, Δvrf1, and Δhox7Δvrf1 at 5 hpi, the expression level of genes related to cell wall remodeling was changed. Genes for melanin synthesis, chitin and glucan degradation, and extracellular cell wall degrading enzyme were significantly downregulated, while genes for chitin and glucan synthesis were upregulated. After 8 hpi, the incipient appressoria of Δhox7, Δvrf1, and Δhox7Δvrf1 regerminated and formed swollen hyphal-like structures with multiple nuclei. The ratio of the nuclear number of the hyphal-like structures of Δhox7, Δhox7Δvrf1, and Δvrf1 was close to 6:4:2 at 24 hpi. Therefore, although Vrf1 and Hox7 are somewhat functionally different, they synergistically regulate appressorium maturation in M. oryzae.


Assuntos
Magnaporthe , Oryza , Ascomicetos , Quitina/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Glucanos/metabolismo , Magnaporthe/metabolismo , Oryza/microbiologia , Doenças das Plantas/microbiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
6.
Int J Mol Sci ; 23(14)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35887015

RESUMO

Magnaporthe oryzae is the causal agent of rice blast, leading to significant reductions in rice and wheat productivity. Nap1 is a conserved protein in eukaryotes involved in diverse physiological processes, such as nucleosome assembly, histone shuttling between the nucleus and cytoplasm, transcriptional regulation, and the cell cycle. Here, we identified Nap1 and characterized its roles in fungal development and virulence in M. oryzae. MoNap1 is involved in aerial hyphal and conidiophore differentiation, sporulation, appressorium formation, plant penetration, and virulence. ΔMonap1 generated a small, elongated, and malformed appressorium with an abnormally organized septin ring on hydrophobic surfaces. ΔMonap1 was more sensitive to cell wall integrity stresses but more resistant to microtubule stresses. MoNap1 interacted with histones H2A and H2B and the B-type cyclin (Cyc1). Moreover, a nuclear export signal (NES) domain is necessary for Nap1's roles in the regulation of the growth and pathogenicity of M. oryzae. In summary, NAP1 is essential for the growth, appressorium formation, and pathogenicity of M. oryzae.


Assuntos
Magnaporthe , Oryza , Ascomicetos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Histonas/metabolismo , Naftalenos , Proteína 1 de Modelagem do Nucleossomo/genética , Proteína 1 de Modelagem do Nucleossomo/metabolismo , Oligopeptídeos , Oryza/metabolismo , Doenças das Plantas/microbiologia , Esporos Fúngicos/metabolismo , Virulência
7.
Microbiol Res ; 259: 126999, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35305442

RESUMO

The rice blast fungus Pyricularia oryzae differentiates into an infection structure, called an appressorium, for plant penetration. The process of appressorium formation requires the transformation of polarized growth to isotropic growth, while penetration requires the opposite growth transformation from isotropic to polarized. Polarized growth requires coordinated organization of cytoskeletal elements, such as microtubule and actin. We identified PoTea1, a homolog of Tea1 from Schizosaccharomyces pombe, and characterized its roles in P. oryzae. After PoTEA1 deletion, ∆Potea1 displayed slowed hyphal growth, decreased sporulation, increased hyphal branches, abnormal two-celled spores, and reduced plant penetration and virulence. During appressorium formation, ∆Potea1 developed a long germ tube with a small appressorium, leading to delayed appressorium differentiation and reduced glycogen and lipid droplet degradation. ∆Potea1 is defective in cAMP-PKA and Pmk1 MAPK pathways. PoTea1 localized at hyphal tips and appressoria as bright dots and was highly dynamic during appressorium formation. PoTea1 formed a complex with itself by self-assembly that was highly dependent on its kelch motif. The coiled-coil motif C2 of PoTea1 is involved in self polymerization and appressorium formation. Benomyl and latrunculin A, two cytoskeleton inhibitors, disturbed the stable localization of PoTea1 at vegetative hyphal tips. We speculate that PoTea1 functions in appressorium formation and virulence by mediating cell polarity in P. oryzae.


Assuntos
Magnaporthe , Oryza , Ascomicetos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Repetição Kelch , Morfogênese , Oryza/microbiologia , Doenças das Plantas/microbiologia , Esporos Fúngicos
8.
Front Microbiol ; 13: 843838, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35295315

RESUMO

The rice blast pathogen, Magnaporthe oryzae, spreads through spores and invades rice through appressoria. Melanin is necessary for an appressorium to penetrate plant cells, but there are many unknown aspects of its role in fungal conidiation. In this study, we confirmed that melanin promotes spore production in M. oryzae, and that this effect is related to the background melanin content of wild-type strains. In the wild-type 70-15 strain with low melanin content of aerial hyphae, increased melanin synthesis promoted sporulation. In contrast, increased melanin synthesis in the wild-type Guy11 strain, which has higher melanin content, did not promote sporulation. The transcription factor Cnf1 (conidial production negative regulatory factor 1), which negatively regulates melanin synthesis, has opposite effects in conidiophore differentiation of Guy11 and 70-15. Deletion of CNF1 did not abolish the defects of Δcos1 and Δhox2 (where COS1/conidiophore stalk-less 1 or HOX2/homeodomain protein 2 was deleted) in conidiation, while increased the conidiation of Δgcc1 and Δgcf3 (where GCC1/growth, conidiation and cell wall regulatory factor 1, or GCF3/growth and conidiation regulatory factor 3 was deleted). Pig1 (pigment of Magnaporthe 1) regulates the melanin synthesis of hyphae but not of conidiophores, spores, or appressoria. Deletion of the same gene in different wild-type strains can lead to different phenotypes, partly because of differences in melanin content between fungal strains. Overall, this study reveals the functional diversity and complexity of melanin in different M. oryzae strains.

9.
J Fungi (Basel) ; 8(2)2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35205898

RESUMO

The appressorium is a specialized structure that is differentiated from Magnaporthe oryzae spores that can infect host cells. In the process of cellular transformation from spore to appressorium, the contents inside the spores are transferred into appressoria, accompanied by major differences in the gene expression model. In this study, we reported a transcription factor (TF), Pcf1, which was depressed at the transcription level and degraded at the protein level in nuclei of incipient appressoria at four hpi (hours post inoculation). To investigate its degradation mechanism, the interacting proteins of Pcf1 were identified using an immunoprecipitation-mass spectrometry (IP-MS) assay. Yeast two-hybrid (Y2H) and co-IP (co-immunoprecipitation) assays confirmed that Pcf1 interacted with the casein kinase 2 (CK2) holoenzyme through direct combination with the CKb2 subunit. Moreover, Pcf1 was ubiquitinated in the hyphae. These changes in Pcf1 protein levels in nuclei provide a new clue of how TFs are degraded during appressorium formation: temporarily unnecessary TFs in spores are phosphorylated through interacting with CK2 enzyme and are then ubiquitinated and digested by the ubiquitin proteasome system (UPS).

10.
Front Plant Sci ; 12: 702368, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34589096

RESUMO

Pyricularia oryzae is an important plant pathogenic fungus that can severely damage rice and wheat crops, leading to significant reductions in crop productivity. To penetrate into and invade tissues of its plant host, this fungus relies on an invasive structure known as an appressorium. Appressorium formation is rigorously regulated by the cAMP-PKA and Pmk1 MAPK pathways. Here, we identified PoRal2, a homologous protein of Schizosaccharomyces pombe Ral2, and characterized its roles in fungal development and virulence in P. oryzae. PoRal2 contains N-terminal kelch repeats and C-terminal BTB domains. PoRal2 is involved in sporulation, aerial hypha and conidiophore differentiation, appressorium formation, plant penetration, and virulence. During appressorium formation, ∆Poral2 mutants generate appressoria with long germ tubes on hydrophobic surfaces. ∆Poral2 mutants exhibited a defective response to exogenous cAMP and the activated RAS2 G18V on a hydrophilic surface, indicating impairment in the cAMP-PKA or Pmk1 MAPK signaling pathways. Deletion of PoRAL2 leads to lowered Pmk1 phosphorylation level in the mutant. Moreover, PoRal2 is found to interact with Scd1, Smo1, and Mst50, which are involved in activation of Pmk1. In addition, the expression levels of MPG1, WISH, and PDEH in the cAMP-PKA pathway, RAS2 in both the cAMP-PKA and Pmk1 MAPK pathways, and melanin biosynthesis genes (ALB1, BUF1, and RSY1) were significantly down-regulated in the ∆Poral2. Therefore, PoRal2 is involved in fungal development and virulence by its crosstalk in the cAMP-PKA and Pmk1 MAPK signaling pathways.

11.
Molecules ; 26(9)2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-34064330

RESUMO

Several genetic studies have identified a rare variant of triggering receptor expressed on myeloid cells 2 (TREM2) as a risk factor for Alzheimer's disease (AD). However, findings on the effects of TREM2 on Aß deposition are quite inconsistent in animal studies, requiring further investigation. In this study, we investigated whether elevation of TREM2 mitigates Aß pathology in TgCRND8 mice. We found that peripheral nerve injury resulted in a robust elevation of TREM2 exclusively in reactive microglia in the ipsilateral spinal cord of aged TgCRND8 mice at the age of 20 months. TREM2 expression appeared on day 1 post-injury and the upregulation was maintained for at least 28 days. Compared to the contralateral side, neither amyloid beta plaque load nor soluble Aß40 and Aß42 levels were attenuated upon TREM2 induction. We further showed direct evidence that TREM2 elevation in reactive microglia did not affect amyloid-ß pathology in plaque-bearing TgCRND8 mice by applying anti-TREM2 neutralizing antibody to selectively block TREM2. Our results question the ability of TREM2 to ameliorate established Aß pathology, discouraging future development of disease-modifying pharmacological treatments targeting TREM2 in the late stage of AD.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Glicoproteínas de Membrana/metabolismo , Microglia/metabolismo , Microglia/patologia , Receptores Imunológicos/metabolismo , Envelhecimento/patologia , Animais , Plexo Braquial , Proteínas de Ligação ao Cálcio/metabolismo , Modelos Animais de Doenças , Masculino , Camundongos Transgênicos , Proteínas dos Microfilamentos/metabolismo , Nervos Periféricos/patologia , Medula Espinal/metabolismo , Medula Espinal/patologia , Corno Dorsal da Medula Espinal/patologia
12.
Lasers Med Sci ; 36(2): 339-347, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32623604

RESUMO

This study aims to evaluate the photodynamic efficacy of purpurin 18 (pu-18) on triple negative breast cancer both in vitro and in vivo. Two states of 4T1 cells, 2D culture and 3D spheroids, were used to evaluate the photodynamic action of pu-18 in vitro. The in vitro study results indicated that for the 4T1 2D cell culture, the photodynamic therapy (PDT) treatment showed significant photocytotoxicity at low pu-18 concentrations following light irradiation. Pu-18 was found to distribute on the lysosomes, mitochondria, Golgi apparatus, and endoplasmic reticulum. After irradiation, pu-18 can generate ROS to destroy the mitochondrial membrane potential (MMP) and eventually induce apoptosis in the 2D 4T1 cells. Light-activated pu-18 could also induce the destruction of the 3D 4T1 cell spheroids. The in vivo study was conducted by using a subcutaneous 4T1 breast cancer animal model. The results demonstrated that pu-18 could remain in the tumor for more than 4 days by direct intra-tumoral injection. The PDT treatment was performed every 2 days for a total of 3 times. The results showed that PDT treatment could significantly inhibit tumor growth in vivo, indicating a good photodynamic efficacy of pu-18 in the mouse breast cancer model, without influencing weight and major organ function. The survival pattern results showed that PDT treatment could largely extend the survival time of mice with breast cancer. The preliminary conclusion is that photodynamic treatment using pu-18 is effective at preventing the growth of triple negative breast cancer cells both in vitro and in vivo. A combination of light irradiation and pu-18 could therefore be a worthwhile approach for the treatment of triple negative breast cancer.


Assuntos
Apoptose , Fotoquimioterapia , Porfirinas/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Peso Corporal/efeitos dos fármacos , Peso Corporal/efeitos da radiação , Linhagem Celular Tumoral , Feminino , Humanos , Luz , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos da radiação , Camundongos Endogâmicos BALB C , Mitocôndrias/efeitos dos fármacos , Imagem Óptica , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/farmacologia , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/patologia , Esferoides Celulares/efeitos da radiação , Frações Subcelulares/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/efeitos da radiação
13.
Biomed Pharmacother ; 127: 110187, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32361638

RESUMO

Increasing evidence suggests that activation of satellite glia cells (SGCs) in sensory ganglia play important roles in the development of neuropathic pain. The present study aimed to investigate the involvement of SGC activation in a novel model of motor nerve injury induced pain hypersensitivity. The neuropathic pain model was established by cervical 8 ventral root avulsion (C8VA). Glial fibrillary acidic protein (GFAP) was used as a marker of SGC activation. Unilateral C8VA resulted in mechanical allodynia, but not thermal hyperalgesia in bilateral paws. Expectedly, SGCs were robustly activated on as early as 1 day and persisted for at least 7 days in the ipsilateral and contralateral dorsal root ganglia (DRG) of C6, C7 and C8 after C8VA. Double immunofluorescence showed that almost all the activated SGCs enveloped neurofilament 200 (NF200) positive myelinated neurons in DRG. Local application of fluorocitrate (FC), a glial metabolism inhibitor, significantly decreased the number of activated SGCs and alleviated bilateral mechanical allodynia. These results suggest that SGC activation contributed to ipsilateral and mirror-image pain hypersensitivity after C8VA. Inhibition of SGC activation represented a promising therapeutic strategy for the management of neuropathic pain following brachial plexus root avulsion.


Assuntos
Hiperalgesia/fisiopatologia , Neurônios Motores/patologia , Neuralgia/fisiopatologia , Células Satélites Perineuronais/metabolismo , Animais , Citratos/farmacologia , Modelos Animais de Doenças , Gânglios Espinais/citologia , Gânglios Espinais/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Hiperalgesia/etiologia , Masculino , Proteínas de Neurofilamentos/metabolismo , Ratos , Ratos Sprague-Dawley
14.
Mol Neurobiol ; 57(1): 278-289, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31325023

RESUMO

Cerebral amyloid angiopathy (CAA) refers to pathological changes occurring in cerebral blood vessels caused by deposition of beta amyloid (Aß) protein. However, the mechanisms involved in the origin of Aß for the formation of CAA and its link to parenchymal amyloid depositions remained to be unraveled. Here, we found CAA and parenchymal plaques distributed separately instead of mingling with each other in the spinal cord of TgCRND8 mice. Parenchymal plaques predominantly located in the dorsal horn whereas CAA distributed in the ventral horn. We further found that the ratio of Aß40/Aß42 was significantly higher in the ventral than that in the dorsal by ELISA assay, suggesting that origin of Aß forming parenchymal plaques may be different from that of CAA in the spinal cord. This hypothesis was further demonstrated by the surgical methods which indicated eliminating parenchymal plaques did not alter CAA in the affected spinal cord. We also examined the ratio of Aß40/Aß42 in the cerebral spinal fluid (CSF) in order to identify the origin of the CAA formation, and found the Aß40/Aß42 ratio was similar to that of CAA formation in the ventral horn. We further demonstrated that CSF tracer distributed along ventral horn vessels, in exactly the same pattern as Aß deposition in CAA in ventral part of spinal cord. These findings verified the concept that CSF influx may act as a constant source for delivering Aß, and contribute to the growth of paraarterial deposits in CAA. Taken together, the results of the present study highlight the important role of the Aß40/Aß42 ratio in determining vascular versus parenchymal amyloid deposition. Unlike parenchymal plaques, Aß of CAA comes from CSF; thus, manipulation of CSF Aß could represent a novel strategy to treat CAA.


Assuntos
Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Placa Amiloide/patologia , Medula Espinal/patologia , Envelhecimento/patologia , Animais , Angiopatia Amiloide Cerebral/patologia , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Córtex Motor/patologia , Medula Espinal/irrigação sanguínea , Traumatismos da Medula Espinal/patologia
15.
Free Radic Biol Med ; 143: 454-470, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31472247

RESUMO

Brachial plexus avulsion (BPA) occurs when the spinal nerve roots are pulled away from the surface of the spinal cord and disconnects neuronal cell body from its distal downstream axon, which induces massive motoneuron death, motor axon degeneration and de-innervation of targeted muscles, thereby resulting in permanent paralysis of motor functions in the upper limb. Avulsion injury triggers oxidative stress and intense local neuroinflammation at the lesioned site, leading to the death of most motoneurons. Berberine (BBR), a natural isoquinoline alkaloid derived from medicinal herbs of Berberis and Coptis species, has been reported to possess neuro-protective, anti-inflammatory and anti-oxidative effects in various animal models of central nervous system (CNS)-related disorders. In this study, we aimed to investigate the effect of BBR on motoneuron survival and axonal regeneration following spinal root avulsion plus re-implantation in rats. Our results indicated BBR significantly accelerated motor function recovery in the forelimb as revealed by the increased Terzis grooming test score, facilitated motor axon regeneration as evidenced by the elevated number of Fluoro-Gold-labeled and P75-positive regenerative motoneurons. The survival of motoneurons was notably promoted by BBR administration presented with boosted ChAT-immunopositive and neutral red-stained neurons. BBR treatment efficiently alleviated muscle atrophy, attenuated functional motor endplates loss in biceps and prevented the reduction of motor axons in the musculocutaneous nerve. Additionally, BBR treatment markedly mitigated the avulsion-induced neuroinflammation via inhibiting microglial and astroglial reactivity, up-regulated the expression of antioxidative indicator Cu/Zn SOD, and down-regulated the levels of nNOS, 3-NT, lipid peroxidation and NF-κB, as well as promoted SIRT1, PI3K and Akt activation. Collectively, BBR might be a promising therapy to assist re-implantation surgery for the treatment of BPA.


Assuntos
Axônios/fisiologia , Berberina/farmacologia , Neurônios Motores/citologia , Regeneração Nervosa/efeitos dos fármacos , Reimplante/métodos , Traumatismos da Medula Espinal/prevenção & controle , Raízes Nervosas Espinhais/cirurgia , Animais , Feminino , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/metabolismo , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/etiologia , Traumatismos da Medula Espinal/patologia , Raízes Nervosas Espinhais/lesões , Raízes Nervosas Espinhais/patologia , Nervos Espinhais/transplante
16.
Neuroscience ; 409: 152-161, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-31034974

RESUMO

Axonopathy manifested by axon swellings might constitute one of the earliest pathological features of Alzheimer's disease. It has been proposed that axonopathy might be associated with the origin of Aß plaques. However, how axonopathy leads to Aß plaque pathogenesis remains elusive. Our previous studies have shown that Aß neuropathology (mainly diffuse plaques) selectively occurred in the regions of corticospinal tract (CST) pathway and its innervated region in the spinal cord of TgCRND8 mice. In this study, we investigated the occurrence and progression of axonopathy and the possible implication in Aß plaque pathogenesis in the spinal cord of TgCRND8 mice. By anterograde labeling of CST system with a neuroanatomical tracer, we found that dilated corticospinal axons started to appear at 7 months, then exhibited an age-dependent increase. These abnormal structures appear before any plaque deposits are visible in the spinal cord of the mice. Importantly, they colocalized with Aß plaques in either the white matter or gray matter of the spinal cord at later stages, suggesting that these axonal swellings might represent the initial stages of Aß plaque formation, and could play a role in Aß plaque pathogenesis. Furthermore, using ultrastructural analysis we demonstrated that intracellular contents in the axonal dystrophies such as various dense vesicles leaked out into the extracellular matrix under a condition of axon swelling rupture in CST pathways of spinal cord. This provided precise structural evidence that how the Aß leaks out from the axonal dystrophies into extracellular matrix and how an axonal swelling might serve as a nidus of amyloid plaque formation.


Assuntos
Doença de Alzheimer/patologia , Axônios/patologia , Placa Amiloide/patologia , Medula Espinal/patologia , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Animais , Modelos Animais de Doenças , Substância Cinzenta/patologia , Camundongos , Camundongos Transgênicos , Tratos Piramidais/patologia , Substância Branca/patologia
17.
Front Pharmacol ; 9: 1374, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30538634

RESUMO

Cancer is still a severe threat to the health of people worldwide. Chemotherapy is one of main therapeutic approaches to combat cancer. However, chemotherapy only has a limited success with severe side effects, especially causing damage to normal tissues such as bone marrow, gastrointestine, heart, liver, renal, neuron, and auditory tissues, etc. The side-effects limit clinical outcome of chemotherapy and lower patients' quality of life, and even make many patients discontinue the chemotherapy. Thus, there is a need to explore effective adjuvant strategies to prevent and reduce the chemotherapy-induced side effects. Naturally occurring products provide a rich source for exploring effective adjuvant agents to prevent and reduce the side effects in anticancer chemotherapy. Curcumin is an active compound from natural plant Curcuma longa L., which is widely used as a coloring and flavoring agent in food industry and a herbal medicine in Asian countries for thousands of years to treat vomiting, headache, diarrhea, etc. Modern pharmacological studies have revealed that curcumin has strong antioxidative, anti-microbial, anti-inflammatory and anticancer activities. Growing evidence shows that curcumin is able to prevent carcinogenesis, sensitize cancer cells to chemotherapy, and protect normal cells from chemotherapy-induced damages. In the present article, we review the preventive effect of curcumin against chemotherapy-induced myelosuppression, gastrointestinal toxicity, cardiotoxicity, hepatotoxicity, nephrotoxicity, neurotoxicity, ototoxicity, and genotoxicity, and discuss its action mechanisms.

18.
Environ Microbiol ; 20(9): 3427-3441, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30126031

RESUMO

Pyricularia oryzae is a plant pathogen causing rice blast, a serious disease spreading in cultivated rice globally. Transcription factors play important regulatory roles in fungal development and pathogenicity. Here, we characterized the biological functions of Crf1, a basic helix-loop-helix (bHLH) transcription factor, in the development and pathogenicity of P. oryzae with functional genetics, molecular and biochemical approaches. We found that CRF1 is necessary for virulence and plays an indispensable role in the regulation of carbohydrate and lipid metabolism in P. oryzae. Deletion of CRF1 led to defects in utilization of lipids, ethanol, glycerol and L-arabinose, and down-regulation of many important genes in lipolysis, ß-oxidation, gluconeogenesis, as well as glycerol and arabinose metabolism. CRF1 is also essential for peroxisome and vacuole function, and conidial cell death during appressorium formation. The appressorium turgor, penetration ability and virulence in Δcrf1 were restored by supplementation of exogenous glucose. The virulence of Crf1 mutant was also recovered by adding exogenous D-xylose, but not by addition of ethanol, pyruvate, leucine or L-arabinose. These data showed that Crf1 plays an important role in the complex regulatory network of carbohydrate and lipid metabolism that governs fungal development and pathogenicity.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Metabolismo dos Carboidratos , Proteínas Fúngicas/metabolismo , Metabolismo dos Lipídeos , Magnaporthe/metabolismo , Magnaporthe/patogenicidade , Oryza/microbiologia , Doenças das Plantas/microbiologia , Fatores de Transcrição/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Magnaporthe/genética , Magnaporthe/crescimento & desenvolvimento , Deleção de Sequência , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/metabolismo , Esporos Fúngicos/patogenicidade , Fatores de Transcrição/genética , Virulência
19.
Fitoterapia ; 127: 245-251, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29496564

RESUMO

Six new cassaine diterpenoids (1, 3-7), along with three known ones (2, 8-9) were isolated from the seeds of Erythrophleum fordii. Their structures were elucidated by extensive spectroscopic methods and acid hydrolysis. Compound 2 was tested to be the most potent one and showed more sensitive activities on MCF-7 and A549 cancer cells with IC50 values of 3.66 ±â€¯1.20 and 2.87 ±â€¯0.46 µM, respectively. Furthermore, compound 2 reduced the number of cell colonies significantly in a dose-dependent manner in the colony formation assay and triggered apoptosis of MCF-7 cell.


Assuntos
Alcaloides/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Diterpenos/isolamento & purificação , Fabaceae/química , Abietanos , Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Diterpenos/farmacologia , Humanos , Estrutura Molecular , Extratos Vegetais/química , Sementes/química
20.
Mol Plant Pathol ; 18(8): 1075-1088, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-27434465

RESUMO

Magnaporthe oryzae is a cereal pathogen causing 20%-30% rice yield losses. Regulatory factor X transcription factors are highly conserved proteins with diverse functions among organisms. Here, we show that MoRfx1 is required for cell division, development and pathogenicity in M. oryzae. Deletion of MoRFX1 resulted in reduced growth and conidiation, decreased appressorium turgor and impaired virulence. ΔMorfx1 displayed increased sensitivity to UV light, four DNA-damaging agents and three cell wall-perturbing compounds. However, ΔMorfx1 showed decreased sensitivity to bleomycin, a DNA/cell wall-damaging agent, and increased chitin content of the cell wall in vegetative mycelium. In addition, cell division speed was reduced in ΔMorfx1, and ΔMorfx1 did not produce three-celled conidia. RNA-sequencing and quantitative polymerase chain reaction analyses suggested that MoRfx1 has bipartite functions in the control of the expression of genes required for cell division and chitin metabolism, not only as a transcriptional repressor, but also as a transcriptional activator. In particular, the expression of chitin deacetylase genes MoCDA2 and MoCDA1 was greatly down-regulated in ΔMorfx1, and deletion of MoCDA2 and MoCDA1, similar to ΔMorfx1, increased resistance to bleomycin. Taken together, our results indicate that MoRFX1 regulates development and pathogenicity by modulating the expression of genes involved in cell division and cell wall integrity.


Assuntos
Proteínas Fúngicas/metabolismo , Magnaporthe/crescimento & desenvolvimento , Magnaporthe/patogenicidade , Oryza/microbiologia , Doenças das Plantas/microbiologia , Divisão Celular , Núcleo Celular/metabolismo , Parede Celular/metabolismo , Quitina/metabolismo , Dano ao DNA , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Magnaporthe/genética , Mutação/genética , Micélio/genética , Micélio/metabolismo , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Esporos Fúngicos/crescimento & desenvolvimento
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