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1.
Cell ; 187(4): 914-930.e20, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38280375

RESUMO

The gut and liver are recognized to mutually communicate through the biliary tract, portal vein, and systemic circulation. However, it remains unclear how this gut-liver axis regulates intestinal physiology. Through hepatectomy and transcriptomic and proteomic profiling, we identified pigment epithelium-derived factor (PEDF), a liver-derived soluble Wnt inhibitor, which restrains intestinal stem cell (ISC) hyperproliferation to maintain gut homeostasis by suppressing the Wnt/ß-catenin signaling pathway. Furthermore, we found that microbial danger signals resulting from intestinal inflammation can be sensed by the liver, leading to the repression of PEDF production through peroxisome proliferator-activated receptor-α (PPARα). This repression liberates ISC proliferation to accelerate tissue repair in the gut. Additionally, treating mice with fenofibrate, a clinical PPARα agonist used for hypolipidemia, enhances colitis susceptibility due to PEDF activity. Therefore, we have identified a distinct role for PEDF in calibrating ISC expansion for intestinal homeostasis through reciprocal interactions between the gut and liver.


Assuntos
Intestinos , Fígado , Animais , Camundongos , Proliferação de Células , Fígado/metabolismo , PPAR alfa/metabolismo , Proteômica , Células-Tronco/metabolismo , Via de Sinalização Wnt , Intestinos/citologia , Intestinos/metabolismo
2.
Childs Nerv Syst ; 40(4): 1185-1192, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38071636

RESUMO

OBJECTIVE: To analyze the outcomes of hypofractionated stereotactic radiotherapy (HFSRT) for Spetzler Martin grades 4 and 5 arteriovenous malformations (AVMs) in a pediatric population. METHODS: Fourteen patients with Spetzler Martin (SM) grades IV and V large AVMs who underwent HFSRT between January 2013 and July 2019 were retrospectively reviewed. All patients received HFSRT at a dose of 30-36 Gy in 5 to 6 fractions. They were followed up annually with clinical and imaging assessments to evaluate obliteration rates. RESULTS: The median age at presentation was 15 years (range 8-21 years). Ten (71%) were SM grade 4 AVMs and the rest were SM grade 5 AVMs. The majority presented with headache (8 [57%]), and 3 (21%) presented with bleeding. The median nidus volume was 39.4 cc (IQR, 31.4-52.4). Two (14%) patients had infratentorial AVMs. All of them had deep venous drainage. The median clinical follow-up duration was 75 months (range 31-107 months). There was complete obliteration of the nidus in 3 (21%) patients with a median time to obliteration of 39 months. HFSRT resulted in a reduction of the AVM volume to 12 cc or less in nearly 70% of patients. None of the patients experienced re-bleeding. 79% reported an improvement in their symptoms. CONCLUSION: HFSRT is a highly effective treatment for high-grade AVMs in children, which can result in either complete elimination or significant reduction of the nidus volume or make it suitable for additional treatment, such as single-session stereotactic radiosurgery (SRS).


Assuntos
Malformações Arteriovenosas Intracranianas , Radiocirurgia , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Estudos Retrospectivos , Malformações Arteriovenosas Intracranianas/cirurgia , Radiocirurgia/métodos , Resultado do Tratamento , Hipofracionamento da Dose de Radiação , Seguimentos
3.
J Lipid Res ; 64(5): 100358, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36934843

RESUMO

Photoreceptor cells express the patatin-like phospholipase domain-containing 2 (PNPLA2) gene that codes for pigment epithelium-derived factor receptor (PEDF-R) (also known as ATGL). PEDF-R exhibits phospholipase activity that mediates the neurotrophic action of its ligand PEDF. Because phospholipids are the most abundant lipid class in the retina, we investigated the role of PEDF-R in photoreceptors by generating CRISPR Pnpla2 knock-out mouse lines in a retinal degeneration-free background. Pnpla2-/- mice had undetectable retinal Pnpla2 gene expression and PEDF-R protein levels as assayed by RT-PCR and immunofluorescence, respectively. The photoreceptors of mice deficient in PEDF-R had deformities as examined by histology and transmission electron microscopy. Pnpla2 knockdown diminished the PLA2 enzymatic activity of PEDF-R in the retina. Lipidomic analyses revealed the accumulation of lysophosphatidyl choline-DHA and lysophosphatidyl ethanolamine-DHA in PEDF-R-deficient retinas, suggesting a possible causal link to photoreceptor dysfunction. Loss of PEDF-R decreased levels of rhodopsin, opsin, PKCα, and synaptophysin relative to controls. Pnpla2-/- photoreceptors had surface-exposed phosphatidylserine, and their nuclei were TUNEL positive and condensed, revealing an apoptotic onset. Paralleling its structural defects, PEDF-R deficiency compromised photoreceptor function in vivo as indicated by the attenuation of photoreceptor a- and b-waves in Pnpla2-/- and Pnpla2+/- mice relative to controls as determined by electroretinography. In conclusion, ablation of PEDF-R in mice caused alteration in phospholipid composition associated with malformation and malperformance of photoreceptors. These findings identify PEDF-R as an important component for photoreceptor structure and function, highlighting its role in phospholipid metabolism for retinal survival and its consequences.


Assuntos
Degeneração Retiniana , Serpinas , Camundongos , Animais , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Serpinas/genética , Serpinas/metabolismo , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , Degeneração Retiniana/genética , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Retina/metabolismo , Fosfolipases/metabolismo
4.
Mol Psychiatry ; 27(3): 1742-1753, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34759357

RESUMO

Substance use disorders (SUDs) are moderately to highly heritable and are in part cross-transmitted genetically, as observed in twin and family studies. We performed exome-focused genotyping to examine the cross-transmission of four SUDs: alcohol use disorder (AUD, n = 4487); nicotine use disorder (NUD, n = 4394); cannabis use disorder (CUD, n = 954); and nonmedical prescription opioid use disorder (NMPOUD, n = 346) within a large nationally representative sample (n = 36,309), the National Epidemiologic Survey on Alcohol and Related Conditions-III (NESARC-III). All diagnoses were based on in-person structured psychiatric interview (AUDADIS-5). SUD cases were compared alone and together to 3959 "super controls" who had neither a SUD nor a psychiatric disorder using an exome-focused array assaying 363,496 SNPs, yielding a representative view of within-disorder and cross-disorder genetic influences on SUDs. The 29 top susceptibility genes for one or more SUDs overlapped highly with genes previously implicated by GWAS of SUD. Polygenic scores (PGS) were computed within the European ancestry (EA) component of the sample (n = 12,505) using summary statistics from each of four clinically distinct SUDs compared to the 3959 "super controls" but then used for two distinctly different purposes: to predict SUD severity (mild, moderate, or severe) and to predict each of the other 3 SUDs. Our findings based on PGS highlight shared and unshared genetic contributions to the pathogenesis of SUDs, confirming the strong cross-inheritance of AUD and NUD as well as the distinctiveness of inheritance of opioid use disorder.


Assuntos
Transtornos Relacionados ao Uso de Álcool , Alcoolismo , Transtornos Relacionados ao Uso de Opioides , Transtornos Relacionados ao Uso de Substâncias , Tabagismo , Consumo de Bebidas Alcoólicas , Alcoolismo/psicologia , Comorbidade , Humanos , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Transtornos Relacionados ao Uso de Opioides/genética , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/genética , Transtornos Relacionados ao Uso de Substâncias/psicologia , Tabagismo/psicologia
5.
Clin Transplant ; 37(9): e15010, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37144852

RESUMO

INTRODUCTION: Total marrow lymphoid irradiation (TMLI) can deliver higher doses of irradiation without increasing toxicity compared to Total body irradiation (TBI). METHODS: Twenty adult patients undergoing hematopoietic stem cell transplantation (HSCT) for acute lymphoblastic leukemia (ALL) and chronic myeloid leukemia with lymphoid blast crises (CML-LBC) received TMLI and cyclophosphamide for conditioning. Ten patients each received 13.5 or 15 Gy of TMLI. The graft source was peripheral blood stem cells in all, and donors included matched related (n = 15), haplo-identical (n = 3) or matched unrelated donors (n = 2). RESULTS: The median cell dose infused was 9 × 106 CD34/kg (range 4.8-12.4). Engraftment occurred in all (100%) at a median of 15 days (range: 14-17). Toxicity was low with hemorrhagic cystitis seen in two but no sinusoidal obstruction syndrome. Acute GVHD occurred in 40% while chronic GVHD was seen in 70.5%. Viral infections were seen in 55% while blood stream bacterial infections occurred in 20% and invasive fungal disease (IFD) in 10%. The Day 100 non-relapse mortality (NRM) was 10%. At a median follow up of 25 months (range 2-48), two patients have relapsed. Overall survival at 2 years is 80% while the disease-free survival is 75%. CONCLUSIONS: The combination of TMLI and cyclophosphamide for myeloablative conditioning is associated with low toxicity and favorable early outcomes in patients undergoing HSCT for ALL and CML-LBC.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Leucemia Mielogênica Crônica BCR-ABL Positiva , Leucemia Mieloide Aguda , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adulto , Humanos , Medula Óssea/efeitos da radiação , Crise Blástica , Irradiação Linfática , Ciclofosfamida/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/etiologia , Doença Enxerto-Hospedeiro/etiologia , Doença Crônica , Condicionamento Pré-Transplante/efeitos adversos , Leucemia Mieloide Aguda/etiologia , Estudos Retrospectivos
6.
Adv Exp Med Biol ; 1415: 565-569, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37440087

RESUMO

Since its inception, primary retinal cultures have been an in vitro tool for modeling the in vivo environment of the retina for biological studies on development and disease. They offer simple and controlled experimental approaches when compared to in vivo models. In this review we highlight the strengths and weaknesses of primary retinal culture models, and the features of dispersed retinal cell cultures.


Assuntos
Técnicas de Cultura de Células , Retina , Neurônios , Biologia , Diferenciação Celular
7.
Plant Dis ; 107(11): 3383-3388, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37330631

RESUMO

Root-knot nematodes (RKNs) cause significant economic damage to crop plants, spurring demand for safe, affordable, and sustainable nematicides. A previous study by our research team showed that the combination of two nematicidal secondary metabolites (SMs) derived from Photorhabdus bacteria, trans-cinnamic acid (t-CA), and (4E)-5-phenylpent-4-enoic acid (PPA) have a synergistic effect against RKNs in vitro. In this study, we considered in planta assays to assess the effects of this SM mixture on the virulence and reproductive fitness of the RKN Meloidogyne incognita in a cowpea. Factorial combinations of five t-CA + PPA concentrations (0, 9.0, 22.9, 57.8, and 91.0 µg/ml) and two nematode inoculation conditions (presence or absence) were evaluated in 6-week growth chamber experiments. Results from this study showed that a single root application of the t-CA + PPA mixture significantly reduced the penetration of M. incognita infective juveniles (J2s) into the cowpea roots. The potential toxicity of t-CA + PPA on RKN-susceptible cowpea seedlings was also investigated. The effect of t-CA + PPA × nematode inoculation interactions and the t-CA + PPA mixture did not show significant phytotoxic effects, nor did it adversely affect plant growth parameters or alter leaf chlorophyll content. Total leaf chlorophyll and chlorophyll b content were significantly reduced (by 15 and 22%, respectively) only by the nematode inoculum and not by any of the SM treatments. Our results suggest that a single root application of a mixture of t-CA and PPA reduces M. incognita J2's ability to infect the roots without impairing plant growth or chlorophyll content.


Assuntos
Photorhabdus , Tylenchoidea , Vigna , Animais , Antinematódeos/farmacologia , Clorofila
8.
Biochem Biophys Res Commun ; 605: 148-153, 2022 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-35334413

RESUMO

Pigment epithelium-derived factor (PEDF) is a secreted protein that is essential in tissue homeostasis and is involved in multiple functions in the eye, such as antiangiogenesis and neuroprotection. However, short retention in the retinal microenvironment can limit its therapeutic effects. In this study, we modified the amino acid sequence of PEDF to increase its affinity for heparin and hyaluronic acid (HA), which are negatively charged extracellular matrix (ECM) molecules. HA is the major component of the vitreous humor. We selectively converted neutral or anionic residues into cationic residues to obtain engineered PEDF (ePEDF). Using in vitro binding assays, we demonstrate that ePEDF had higher affinity for heparin and HA than wild-type PEDF (wtPEDF). ePEDF exhibited antiangiogenic and retinal survival bioactivities. It inhibited endothelial cell proliferation and tube formation in vitro. In an ex vivo model mimicking retinal degeneration, ePEDF protected photoreceptors from cell death. The findings suggest that protein engineering is an approach to develop active PEDF with higher ECM affinity to potentially improve its retention in the retina microenvironment and in turn make it a more efficient therapeutic drug for retinal diseases.


Assuntos
Glicosaminoglicanos , Serpinas , Proteínas do Olho/metabolismo , Heparina/metabolismo , Ácido Hialurônico , Fatores de Crescimento Neural/metabolismo , Serpinas/metabolismo
9.
Protein Expr Purif ; 194: 106072, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35181508

RESUMO

Human SERPINF1 gene codes for pigment epithelium-derived factor (PEDF), a secreted glycoprotein and member of the SERPIN superfamily. To obtain large amounts of recombinant PEDF proteins, we subcloned the coding sequence of human SERPINF1 mutated versions into the pCEP4 vector and generated stably transfected HEK.Ebna cells. The cells produced and secreted recombinant PEDF proteins into the culturing media. The recombinant PEDF proteins were purified by ion-exchange column chromatography and milligram amounts of highly purified protein were recovered. PEDF has affinity for PEDF-receptor (PEDF-R), a membrane-linked lipase encoded by the PNPLA2 gene. Recombinant PEDF-R truncated versions were obtained from Escherichia coli containing expression vectors with human PNPLA2 cDNAs with 3'end deletions and by induction with isopropyl ß-d-1-thiogalactopyranoside. The bacterially derived PEDF-R proteins in insoluble inclusion bodies were solubilized with urea and purified by cation-exchange column chromatography. C-terminally truncated PEDF-R versions containing the ligand binding region retained the ability to bind PEDF. The data demonstrate that mammalian-derived recombinant PEDF and bacterially derived recombinant PEDF-R can be produced and purified in large amounts for further use in structural and biological studies.


Assuntos
Serpinas , Animais , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Humanos , Mamíferos , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , Receptores de Neuropeptídeos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Serpinas/genética , Serpinas/metabolismo
10.
Int J Mol Sci ; 23(14)2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35887093

RESUMO

The retinal pigment epithelium (RPE) expresses the Serpinf1 gene to produce pigment epithelium-derived factor (PEDF), a retinoprotective protein that is downregulated with cell senescence, aging and retinal degenerations. We determined the expression of senescence-associated genes in the RPE of 3-month-old mice that lack the Serpinf1 gene and found that Serpinf1 deletion induced H2ax for histone H2AX protein, Cdkn1a for p21 protein, and Glb1 gene for ß-galactosidase. Senescence-associated ß-galactosidase activity increased in the Serpinf1 null RPE when compared with wild-type RPE. We evaluated the subcellular morphology of the RPE and found that ablation of Serpinf1 increased the volume of the nuclei and the nucleoli number of RPE cells, implying chromatin reorganization. Given that the RPE phagocytic function declines with aging, we assessed the expression of the Pnpla2 gene, which is required for the degradation of photoreceptor outer segments by the RPE. We found that both the Pnpla2 gene and its protein PEDF-R declined with the Serpinf1 gene ablation. Moreover, we determined the levels of phagocytosed rhodopsin and lipids in the RPE of the Serpinf1 null mice. The RPE of the Serpinf1 null mice accumulated rhodopsin and lipids compared to littermate controls, implying an association of PEDF deficiency with RPE phagocytosis dysfunction. Our findings establish PEDF loss as a cause of senescence-like changes in the RPE, highlighting PEDF as both a retinoprotective and a regulatory protein of aging-like changes associated with defective degradation of the photoreceptor outer segment in the RPE.


Assuntos
Epitélio Pigmentado da Retina , Serpinas , Animais , Células Cultivadas , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Lipídeos , Camundongos , Camundongos Knockout , Fatores de Crescimento Neural , Fagocitose/genética , Epitélio Pigmentado da Retina/metabolismo , Rodopsina/metabolismo , Serpinas/metabolismo , beta-Galactosidase/metabolismo
11.
J Neurochem ; 159(5): 840-856, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34133756

RESUMO

Pigment epithelium-derived factor (PEDF) is a cytoprotective protein for the retina. We hypothesize that this protein acts on neuronal survival and differentiation of photoreceptor cells in culture. The purpose of the present study was to evaluate the neurotrophic effects of PEDF and its fragments in an in vitro model of cultured primary retinal neurons that die spontaneously in the absence of trophic factors. We used Wistar albino rats. Cell death was assayed by immunofluorescence and flow cytometry through TUNEL assay, propidium iodide, mitotracker, and annexin V. Immunofluorescence of cells for visualizing rhodopsin, CRX, and antisyntaxin under confocal microscopy was performed. Neurite outgrowth was also quantified. Results show that PEDF protected photoreceptor precursors from apoptosis, preserved mitochondrial function and promoted polarization of opsin enhancing their developmental process, as well as induced neurite outgrowth in amacrine neurons. These effects were abolished by an inhibitor of the PEDF receptor or receptor-derived peptides that block ligand/receptor interactions. While all the activities were specifically conferred by short peptide fragments (17 amino acid residues) derived from the PEDF neurotrophic domain, no effects were triggered by peptides from the PEDF antiangiogenic region. The observed effects on retinal neurons imply a specific activation of the PEDF receptor by a small neurotrophic region of PEDF. Our findings support the neurotrophic PEDF peptides as neuronal guardians for the retina, highlighting their potential as promoters of retinal differentiation, and inhibitors of retinal cell death and its blinding consequences. Cover Image for this issue: https://doi.org/10.1111/jnc.15089.


Assuntos
Células Amácrinas/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proteínas do Olho/farmacologia , Fatores de Crescimento Neural/farmacologia , Crescimento Neuronal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Células Fotorreceptoras de Vertebrados/efeitos dos fármacos , Serpinas/farmacologia , Células Amácrinas/fisiologia , Sequência de Aminoácidos , Animais , Diferenciação Celular/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Proteínas do Olho/genética , Feminino , Masculino , Fatores de Crescimento Neural/genética , Crescimento Neuronal/fisiologia , Neurônios/fisiologia , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/farmacologia , Células Fotorreceptoras de Vertebrados/fisiologia , Ratos , Ratos Wistar , Serpinas/genética
12.
Int J Mol Sci ; 22(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069505

RESUMO

Retinoprotective proteins play important roles for retinal tissue integrity. They can directly affect the function and the survival of photoreceptors, and/or indirectly target the retinal pigment epithelium (RPE) and endothelial cells that support these tissues. Retinoprotective proteins are used in basic, translational and in clinical studies to prevent and treat human retinal degenerative disorders. In this review, we provide an overview of proteins that protect the retina and focus on pigment epithelium-derived factor (PEDF), and its effects on photoreceptors, RPE cells, and endothelial cells. We also discuss delivery systems such as pharmacologic and genetic administration of proteins to achieve photoreceptor survival and retinal tissue integrity.


Assuntos
Proteínas do Olho/metabolismo , Fatores de Crescimento Neural/metabolismo , Retina/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Serpinas/metabolismo , Animais , Células Endoteliais/metabolismo , Humanos , Células Fotorreceptoras/metabolismo , Células Fotorreceptoras de Vertebrados/metabolismo , Transporte Proteico/fisiologia , Retina/fisiologia , Degeneração Retiniana/metabolismo , Neurônios Retinianos/metabolismo
13.
Microbiology (Reading) ; 166(11): 1074-1087, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33064635

RESUMO

Xenorhabdus species are bacterial symbionts of Steinernema nematodes and pathogens of susceptible insects. Different species of Steinernema nematodes carrying specific species of Xenorhabdus can invade the same insect, thereby setting up competition for nutrients within the insect environment. While Xenorhabdus species produce both diverse antibiotic compounds and prophage-derived R-type bacteriocins (xenorhabdicins), the functions of these molecules during competition in a host are not well understood. Xenorhabdus bovienii (Xb-Sj), the symbiont of Steinernema jollieti, possesses a remnant P2-like phage tail cluster, xbp1, that encodes genes for xenorhabdicin production. We show that inactivation of either tail sheath (xbpS1) or tail fibre (xbpH1) genes eliminated xenorhabdicin production. Preparations of Xb-Sj xenorhabdicin displayed a narrow spectrum of activity towards other Xenorhabdus and Photorhabdus species. One species, Xenorhabdus szentirmaii (Xsz-Sr), was highly sensitive to Xb-Sj xenorhabdicin but did not produce xenorhabdicin that was active against Xb-Sj. Instead, Xsz-Sr produced high-level antibiotic activity against Xb-Sj when grown in complex medium and lower levels when grown in defined medium (Grace's medium). Conversely, Xb-Sj did not produce detectable levels of antibiotic activity against Xsz-Sr. To study the relative contributions of Xb-Sj xenorhabdicin and Xsz-Sr antibiotics in interspecies competition in which the respective Xenorhabdus species produce antagonistic activities against each other, we co-inoculated cultures with both Xenorhabdus species. In both types of media Xsz-Sr outcompeted Xb-Sj, suggesting that antibiotics produced by Xsz-Sr determined the outcome of the competition. In contrast, Xb-Sj outcompeted Xsz-Sr in competitions performed by co-injection in the insect Manduca sexta, while in competition with the xenorhabdicin-deficient strain (Xb-Sj:S1), Xsz-Sr was dominant. Thus, xenorhabdicin was required for Xb-Sj to outcompete Xsz-Sr in a natural host environment. These results highlight the importance of studying the role of antagonistic compounds under natural biological conditions.


Assuntos
Bacteriocinas/metabolismo , Interações Microbianas , Xenorhabdus/fisiologia , Animais , Antibacterianos/metabolismo , Antibiose , Bacteriocinas/genética , Bacteriófago P2/genética , Manduca/microbiologia , Mutação , Nematoides/microbiologia , Prófagos/genética , Xenorhabdus/genética , Xenorhabdus/metabolismo
14.
Exp Eye Res ; 198: 108121, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32721425

RESUMO

The SERPINF1 gene encodes pigment epithelium-derived factor (PEDF), a member of the serpin superfamily with neurotrophic and antiangiogenic properties in the retina. We hypothesized that absence of PEDF would lead to increased stress-associated retinal degeneration in Serpinf1 null mice. Accordingly, using a Serpinf1 null mouse model, we investigated the impact of PEDF absence on retinal morphology, and susceptibility to induced and inherited retinal degeneration. We studied the pattern of Serpinf1 expression in the mouse retina layers. PEDF protein was detected by western blotting. Transmission electron microscopy was performed on mouse retina. Serpinf1 null mice and wild type littermates were injected with NaIO3 (30 mg/kg body weight) intraperitonially. At post-injection day 1, 3, 4, 6 and 8 mice were euthanized, and eyes were enucleated. Serpinf1 null and rd10 double mutant mice were generated and their eyes enucleated at different time points from post-natal day 15 to post-natal day 28. Enucleated eyes were processed for hematoxylin and eosin staining and histopathological evaluations. We found that Serpinf1 was expressed in the retinal pigment epithelium, in the inner nuclear layer and in the ganglion cell layer, but undetectable in the outer nuclear layer of wild type mice. Plasma PEDF protein levels were undetectable in Serpinf1 null animals. RPE atrophy and retinal thinning were observed in NaIO3-treated wild type mice that progressed with time post-injection. NaIO3-treated Serpinf1 null mice showed comparatively better retinal morphology than wild type mice at day 4 post-injection. However, the absence of PEDF in Serpinf1 null x rd10 mice increased the susceptibility to retinal degeneration relative to that of rd10 mice. We concluded that histopathological evaluation of retinas lacking PEDF showed that removal of the Serpinf1 gene may activate PEDF-independent compensatory mechanisms to protect the retina against oxidative stress, while it increases the susceptibility to degenerate the retina in inherited retinal degeneration models.


Assuntos
Fatores de Crescimento Neural/deficiência , Degeneração Retiniana/metabolismo , Serpinas/deficiência , Animais , Western Blotting , Modelos Animais de Doenças , Progressão da Doença , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , Células Fotorreceptoras de Vertebrados/metabolismo , Células Fotorreceptoras de Vertebrados/patologia , Degeneração Retiniana/patologia , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/patologia , Serpinas/genética , Serpinas/metabolismo
15.
Int J Mol Sci ; 21(19)2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33008127

RESUMO

Here, we evaluated the effects of PEDF (pigment epithelium-derived factor) and PEDF peptides on cone-photoreceptor cell damage in a mouse model of focal LED-induced phototoxicity (LIP) in vivo. Swiss mice were dark-adapted overnight, anesthetized, and their left eyes were exposed to a blue LED placed over the cornea. Immediately after, intravitreal injection of PEDF, PEDF-peptide fragments 17-mer, 17-mer[H105A] or 17-mer[R99A] (all at 10 pmol) were administered into the left eye of each animal. BDNF (92 pmol) and bFGF (27 pmol) injections were positive controls, and vehicle negative control. After 7 days, LIP resulted in a consistent circular lesion located in the supratemporal quadrant and the number of S-cones were counted within an area centered on the lesion. Retinas treated with effectors had significantly greater S-cone numbers (PEDF (60%), 17-mer (56%), 17-mer [H105A] (57%), BDNF (64%) or bFGF (60%)) relative to their corresponding vehicle groups (≈42%). The 17-mer[R99A] with no PEDF receptor binding and no neurotrophic activity, PEDF combined with a molar excess of the PEDF receptor blocker P1 peptide, or with a PEDF-R enzymatic inhibitor had undetectable effects in S-cone survival. The findings demonstrated that the cone survival effects were mediated via interactions between the 17-mer region of the PEDF molecule and its PEDF-R receptor.


Assuntos
Proteínas do Olho/farmacologia , Fatores de Crescimento Neural/farmacologia , Peptídeos/farmacologia , Retina/efeitos dos fármacos , Células Fotorreceptoras Retinianas Cones/efeitos dos fármacos , Serpinas/farmacologia , Animais , Córnea/efeitos dos fármacos , Córnea/crescimento & desenvolvimento , Córnea/metabolismo , Dermatite Fototóxica , Modelos Animais de Doenças , Proteínas do Olho/metabolismo , Humanos , Camundongos , Fatores de Crescimento Neural/metabolismo , Fragmentos de Peptídeos/farmacologia , Peptídeos/genética , Fotoperíodo , Receptores de Neuropeptídeos/genética , Retina/crescimento & desenvolvimento , Células Fotorreceptoras Retinianas Cones/metabolismo , Células Fotorreceptoras Retinianas Cones/patologia , Serpinas/metabolismo
16.
Exp Eye Res ; 184: 24-29, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30980815

RESUMO

The purpose of the study is to evaluate the protective properties of PEDF peptide fragments on rd10 mouse models of retinal degeneration ex vivo. Human recombinant PEDF and synthetic peptides were used. Rd10 retinal explants as well as wild-type retinal explants treated with zaprinast to mimic the rd10 photoreceptor cell death were employed. PEDF protein was intravitreally administered into rd10 mice. Outer nuclear layer thickness measurements in retinal sections, TUNEL labeling in retinal explants, western blots and immunofluorescence with retinal samples were performed. PEDF protein levels in the RPE of rd10 mice decreased with age (P15 - P25). Levels of PEDF receptor PEDF-R declined in the photoreceptor inner segments from rd10 relative to wild-type mice at P25. PEDF administration increased the outer nuclear layer thickness of rd10 retinas in vivo and decreased the number of TUNEL+ nuclei of photoreceptors in rd10 retinal explant cultures, both relative to untreated controls. Peptides containing the PEDF neurotrophic region decreased the number of TUNEL+ photoreceptors in both rd10 and zaprinast-induced cell death ex vivo models, while peptides without the neurotrophic region and/or lacking affinity for PEDF-R were ineffective in protecting photoreceptors. Thus, retinal explants are a valuable system to evaluate PEDF activity. Short peptides with the photoreceptor-protective property of PEDF may prove useful for the development of therapeutic agents for photoreceptor protection in retinal degenerations.


Assuntos
Proteínas do Olho/uso terapêutico , Fatores de Crescimento Neural/uso terapêutico , Fragmentos de Peptídeos/uso terapêutico , Células Fotorreceptoras de Vertebrados/efeitos dos fármacos , Degeneração Retiniana/tratamento farmacológico , Serpinas/uso terapêutico , Animais , Western Blotting , Sobrevivência Celular , Modelos Animais de Doenças , Técnica Indireta de Fluorescência para Anticorpo , Marcação In Situ das Extremidades Cortadas , Injeções Intravítreas , Camundongos , Camundongos Endogâmicos C57BL , Células Fotorreceptoras de Vertebrados/metabolismo , Células Fotorreceptoras de Vertebrados/patologia , Proteínas Recombinantes , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia
17.
J Exp Biol ; 222(Pt 18)2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31511342

RESUMO

In this study, we assessed the effect of symbiotic (cognate and non-cognate) and non-symbiotic bacteria on ascaroside production of first-generation adults in two Steinernema spp.: S. carpocapsae All strain and S. feltiae SN strain. Each nematode species was reared under three bacterial scenarios: (1) cognate symbiotic, (2) non-cognate symbiotic strain and (3) non-cognate symbiotic species. Our results showed S. carpocapsae produced four quantifiable ascaroside molecules: asc-C5, asc-C6, asc-C7 and asc-C11, whereas in S. feltiae only three molecules were detected: asc-C5, asc-C7 and asc-C11. Bacterial conditions did not significantly affect the quantity of the secreted ascarosides in first-generation adults of S. carpocapsae However, in S. feltiae, Xenorhabdus nematophila All strain influenced the production of two ascaroside molecules: asc-C5 and asc-C11.


Assuntos
Feromônios/metabolismo , Rabditídios/metabolismo , Rabditídios/microbiologia , Xenorhabdus , Animais , Bactérias , Fenômenos Fisiológicos Bacterianos , Glicolipídeos/metabolismo , Simbiose
18.
Prev Med ; 118: 336-343, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30508551

RESUMO

Moderate alcohol consumption has been related to lower risk of coronary heart disease (CHD) in the literature. To examine whether alcohol drinking during the past 12 months and heaviest drinking period were differentially associated with the risk of CHD, we designed a case-control study using a population-based health survey of U.S. adults conducted from 2012 to 2013. Respondents who reported to have doctor-ascertained CHD served as cases (n = 1671), and those free of CHD and other alcohol-related health conditions served as controls (n = 17,629) in logistic regressions. Sex-specific quartiles of average daily ethanol intake were ascertained and calculated for the past 12 months and during the period of heaviest lifetime drinking. We further split current drinkers into reducers and non-reducers (past 12 months relative to the heaviest drinking period) to examine CHD risk profiles in association with the 12-month drinking level. Current-drinker reducers (AOR, 95% CI = 1.57 [1.10-2.27] for men; AOR, 95% CI = 1.33 [1.02-1.72] for women) and former drinkers (AOR, 95% CI = 2.06 [1.43-2.97] for men; AOR, 95% CI = 1.51 [1.19-1.92] for women) more often had CHD than lifetime abstainers. Male heavy drinkers during the heaviest drinking period (AOR, 95% CI = 2.25 [1.52-3.32]) were more likely to manifest CHD than lifetime abstainers. In addition, individuals with diagnosed CHD were significantly more likely to have reduced drinking in the past. A change in alcohol consumption over the life course among former and current drinkers may distort the true alcohol-CHD relationship.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Doença das Coronárias/epidemiologia , Comportamentos Relacionados com a Saúde , Adulto , Estudos de Casos e Controles , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estados Unidos
19.
J Invertebr Pathol ; 167: 107251, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31560882

RESUMO

Steinernema nematodes and their Xenorhabdus symbionts are a malleable model system to study mutualistic relations. One of the advantages they possess is their ability to be disassociated under in vitro rearing conditions. Various in vitro methods have been developed to produce symbiont colonized and aposymbiotic (symbiont-free) nematodes. Until now, there has been no investigation on how in vitro rearing conditions may have an impact on the storage ability and the protein content of the infective juvenile at different storage temperatures. Thus, in this study, we investigated how infective juvenile longevity and protein content are impacted when the nematodes were reared with two in vitro methods (lipid and liver kidney agar) considering colonized and uncolonized nematodes, and under two different temperatures: 15 °C and 20 °C (mild stress). Infective juveniles reared in vitro (with or without their symbionts) had lower 8-week survival rates. No in vitro reared, colonized IJs survived to the desired 16-week time point. Survival of infective juveniles stored under mild stress temperature (20 °C) was lower than that observed at 15 °C. However, when comparing the interaction between rearing condition and storage temperature, there were not significant differences. With respect to protein content, in vivo, colonized infective juveniles maintained a static protein content over time, suggesting symbiont colonization may influence protein metabolism and/or turnover in infective juveniles.


Assuntos
Rabditídios/crescimento & desenvolvimento , Animais , Técnicas In Vitro/métodos , Longevidade , Mariposas/parasitologia , Parasitologia/métodos , Proteínas/análise , Rabditídios/microbiologia , Rabditídios/patogenicidade , Análise de Sobrevida , Simbiose/fisiologia , Temperatura , Xenorhabdus/crescimento & desenvolvimento
20.
J Invertebr Pathol ; 165: 22-45, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30940472

RESUMO

Since the 1980s, research into entomopathogenic nematodes (EPNs) in Latin America has produced many remarkable discoveries. In fact, 16 out of the 117 recognized species of EPNs have been recovered and described in the subcontinent, with many more endemic species and/or strains remaining to be discovered and identified. In addition, from an applied perspective, numerous technological innovations have been accomplished in relation to their implementation in biocontrol. EPNs have been evaluated against over 170 species of agricultural and urban insects, mites, and plant-parasitic nematodes under laboratory and field conditions. While much success has been recorded, many accomplishments remain obscure, due to their publication in non-English journals, thesis dissertations, conference proceedings, and other non-readily available sources. The present review provides a brief history of EPNs in Latin America, including current findings and future perspectives.


Assuntos
Agentes de Controle Biológico , Controle de Insetos , Controle Biológico de Vetores , Rabditídios , Agricultura/tendências , Animais , Insetos/parasitologia , Larva/parasitologia , América Latina , Controle Biológico de Vetores/métodos , Controle Biológico de Vetores/tendências , Rabditídios/classificação , Rabditídios/crescimento & desenvolvimento , Rabditídios/isolamento & purificação , Rabditídios/patogenicidade
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