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1.
Proc Natl Acad Sci U S A ; 121(6): e2305947121, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38289952

RESUMO

Optic neuropathies, characterized by injury of retinal ganglion cell (RGC) axons of the optic nerve, cause incurable blindness worldwide. Mesenchymal stem cell-derived small extracellular vesicles (MSC-sEVs) represent a promising "cell-free" therapy for regenerative medicine; however, the therapeutic effect on neural restoration fluctuates, and the underlying mechanism is poorly understood. Here, we illustrated that intraocular administration of MSC-sEVs promoted both RGC survival and axon regeneration in an optic nerve crush mouse model. Mechanistically, MSC-sEVs primarily targeted retinal mural cells to release high levels of colony-stimulating factor 3 (G-CSF) that recruited a neural restorative population of Ly6Clow monocytes/monocyte-derived macrophages (Mo/MΦ). Intravitreal administration of G-CSF, a clinically proven agent for treating neutropenia, or donor Ly6Clow Mo/MΦ markedly improved neurological outcomes in vivo. Together, our data define a unique mechanism of MSC-sEV-induced G-CSF-to-Ly6Clow Mo/MΦ signaling in repairing optic nerve injury and highlight local delivery of MSC-sEVs, G-CSF, and Ly6Clow Mo/MΦ as therapeutic paradigms for the treatment of optic neuropathies.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , Traumatismos do Nervo Óptico , Camundongos , Animais , Axônios/metabolismo , Fator Estimulador de Colônias de Granulócitos/metabolismo , Regeneração Nervosa/fisiologia , Traumatismos do Nervo Óptico/terapia , Traumatismos do Nervo Óptico/metabolismo , Células Ganglionares da Retina/fisiologia , Células-Tronco Mesenquimais/metabolismo , Vesículas Extracelulares/metabolismo , Macrófagos/metabolismo
2.
Proc Natl Acad Sci U S A ; 119(48): e2215328119, 2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36409894

RESUMO

Super-enhancers (SEs) are exceptionally large enhancers and are recognized to play prominent roles in cell identity in mammalian species. We surveyed the genomic regions containing large clusters of accessible chromatin regions (ACRs) marked by deoxyribonuclease (DNase) I hypersensitivity in Arabidopsis thaliana. We identified a set of 749 putative SEs, which have a minimum length of 1.5 kilobases and represent the top 2.5% of the largest ACR clusters. We demonstrate that the genomic regions associating with these SEs were more sensitive to DNase I than other nonpromoter ACRs. The SEs were preferentially associated with topologically associating domains. Furthermore, the SEs and their predicted cognate genes were frequently associated with organ development and tissue identity in A. thaliana. Therefore, the A. thaliana SEs and their cognate genes mirror the functional characteristics of those reported in mammalian species. We developed CRISPR/Cas-mediated deletion lines of a 3,578-bp SE associated with the thalianol biosynthetic gene cluster (BGC). Small deletions (131-157 bp) within the SE resulted in distinct phenotypic changes and transcriptional repression of all five thalianol genes. In addition, T-DNA insertions in the SE region resulted in transcriptional alteration of all five thalianol genes. Thus, this SE appears to play a central role in coordinating the operon-like expression pattern of the thalianol BGC.


Assuntos
Arabidopsis , Triterpenos , Animais , Arabidopsis/genética , Sequências Reguladoras de Ácido Nucleico , Cromatina/genética , Mamíferos/genética
3.
J Am Soc Nephrol ; 35(2): 149-165, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38062563

RESUMO

SIGNIFICANCE STATEMENT: Renal fibrosis is a common pathologic process of progressive CKD. We have provided strong evidence that PGI 2 is an important component in the kidney injury/repairing process by reducing fibrosis and protecting renal function from declining. In our study, administration of a PGI 2 analog or selective PTGIR agonist after the acute injury ameliorated renal fibrosis. Our findings provide new insights into the role of PGI 2 in kidney biology and suggest that targeting PGI 2 /PTGIR may be a potential therapeutic strategy for CKD. BACKGROUND: Prostanoids have been demonstrated to be important modulators to maintain tissue homeostasis in response to physiologic or pathophysiologic stress. Prostacyclin (PGI 2 ) is a member of prostanoids. While limited studies have shown that PGI 2 is involved in the tissue injury/repairing process, its role in renal fibrosis and CKD progression requires further investigation. METHODS: Prostacyclin synthase ( Ptgis )-deficient mice, prostaglandin I 2 receptor ( Ptgir )-deficient mice, and an oral PGI 2 analog and selective PTGIR agonist were used to examine the role of PGI 2 in renal fibrosis in mouse models. We also analyzed the single-cell RNA-Seq data to examine the PTGIR -expressing cells in the kidneys of patients with CKD. RESULTS: Increased PTGIS expression has been observed in fibrotic kidneys in both humans and mice. Deletion of the PTGIS gene aggravated renal fibrosis and decline of renal function in murine models. A PGI 2 analog or PTGIR agonist that was administered after the acute injury ameliorated renal fibrosis. PTGIR, the PGI 2 receptor, deficiency blunted the protective effect of the PGI 2 analog. Fibroblasts and myofibroblasts were the major cell types expressing PTGIR in the kidneys of patients with CKD. Deletion of PTGIR in collagen-producing fibroblastic cells aggravated renal fibrosis. The protective effect of PGI 2 was associated with the inhibition of fibroblast activation through PTGIR-mediated signaling. CONCLUSIONS: PGI 2 is an important component in the kidney injury/repairing process by preventing the overactivation of fibroblasts during the repairing process and protecting the kidney from fibrosis and decline of renal function. Our findings suggest that PGI 2 /PTGIR is a potential therapeutic target for CKD.


Assuntos
Epoprostenol , Insuficiência Renal Crônica , Humanos , Animais , Camundongos , Epoprostenol/farmacologia , Epoprostenol/metabolismo , Prostaglandinas I , Rim/metabolismo , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/etiologia , Fibroblastos/metabolismo , Fibrose
4.
Pflugers Arch ; 471(4): 543-555, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30413885

RESUMO

Prostacyclin, or PGI2, is a product of PGI synthase (PGIS), down-stream of cyclooxygenase pathway. PGI2 has been demonstrated to play an important role in maintaining renal blood flow. Non-steroidal anti-inflammatory drugs (NSAIDs) that inhibit cyclooxygenase are reported to increase the susceptibility of patients to acute kidney injury (AKI). This study explores the role of endothelium-derived prostacyclin in ischemia-reperfusion injury (I/RI). The renal PGIS expression and PGI2 production markedly increased following I/RI. Loss of one allele of PGIS gene or selective endothelial PGIS deletion (TEK-CRE PGISfl/fl mice) caused more severe renal damage following I/RI than control mice. Iloprost, a PGI2 analog, administered 30 min before the I/R surgery, markedly attenuated the renal damage in both control mice and TEK-CRE PGISfl/fl mice. Renal p-PKA expression significantly increased after I/RI in wild-type mice but not in the PGIS deletion mice, consistent with IP receptor mediating the protective effect. Further studies showed that PGIS deficiency was associated with reduced fluorescence microsphere accumulation in the kidney following I/R. Folic acid also induced marked kidney injury; however, endothelial PGIS deletion did not worsen kidney injury compared with wild-type mice. These studies indicate that PGIS-derived PGI2 can protect the kidney from acute injury caused by ischemia and reperfusion and PGIS/PGI2 is a potential intervention target for AKI.


Assuntos
Endotélio/metabolismo , Epoprostenol/metabolismo , Rim/metabolismo , Substâncias Protetoras/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Glucose-6-Fosfato Isomerase/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
5.
Arch Insect Biochem Physiol ; 98(2): e21461, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29600519

RESUMO

The soybean pod borer [SPB; Leguminivora glycinivorella (Mats.) Obraztsov] is a major soybean pest in northeastern Asia. A useful method for addressing this problem is the generation of transgenic plants producing double-stranded RNA (dsRNA) that target essential insect genes. In this study, we confirmed that 18S ribosomal RNA is critical for SPB development. Downregulated Spb18S expression induced by dsRNA injection increased larval mortality rates and resulted in early pupation. We also assessed whether Spb18S is silenced in SPB larvae fed on transgenic soybean expressing Spb18S dsRNA. Transgenic plants downregulated Spb18S expression levels and second-instar larval survival rates. Moreover, such plants were less damaged by SPB larvae than control plants under field conditions.


Assuntos
Glycine max/metabolismo , Mariposas , Plantas Geneticamente Modificadas/metabolismo , RNA de Cadeia Dupla/metabolismo , RNA Ribossômico 18S/metabolismo , Animais , Larva , Interferência de RNA
6.
J Hazard Mater ; 474: 134837, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38850945

RESUMO

Multi-component droplets from daily activities and production processes severely degrade indoor air quality. Their health hazards and removal efficiency depend on size and composition, significantly affected by evaporation and growth. The phase transition process is complex, involving a broad spectrum of droplet sizes with diverse heat and mass transfer characteristics. Components within the droplets experience simultaneous phase transitions at differing rates and mass transfer directions. This study aims to refine the existing evaporation model of single-component droplets in continuous flows by theoretically integrating the effects of varying droplet sizes and multiple components. A multi-component droplet evaporation/growth model that spans the entire range of droplet sizes has been developed, and predictions have been made based on this model. Utilizing MATLAB, this model accurately predicts the indoor dynamics of multi-component droplets, with deviations under 16 % from experiments. It improves accuracy by over 25 % across droplet sizes via dimensionless transfer coefficients and boosts precision by over 24 % for multi-component droplets with zero-diffusion transport. The radius of the droplet after phase change can reach 8.42 × 10-6 m and remains suspended in the air for an extended period. This study establishes a solid theoretical foundation for accurately predicting the indoor distribution of multi-component droplets.

7.
Plants (Basel) ; 13(5)2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38475476

RESUMO

Soybean [Glycine max (L.) Merr.], an essential staple food and oil crop worldwide, boasts abundant vegetable proteins and fats beneficial for both human and animal consumption. However, the soybean pod borer (Leguminivora glycinivorella) (SPB) stands as the most destructive soybean insect pest in northeast China and other northeastern Asian regions, leading to significant annual losses in soybean yield and economic burden. Therefore, this study aims to investigate the introduction of a previously tested codon-optimized cry1c gene, cry1c*, into the soybean genome and assess its effect on the SPB infestation by generating and characterizing stable transgenic soybeans overexpressing cry1c*. The transgenic soybean lines that constitutively overexpressed cry1c* exhibited a significant reduction in the percentage of damaged seeds, reaching as low as 5% in plants under field conditions. Additionally, feeding transgenic leaves to the larvae of S. exigua, S. litura, and M. separta resulted in inhibited larval growth, decreased larval body weight, and lower survival rates compared to larvae fed on wild-type leaves. These findings showed that the transgenic lines maintained their resistance to SPB and other lepidopteran pests, especially the transgenic line KC1. Southern blotting and genome-wide resequencing analysis revealed that T-DNA integration occurred as a single copy between loci 50,868,122 and 50,868,123 of chromosome 10 in the transgenic line KC1. Therefore, the transgenic line KC1, overexpressing high levels of cry1c* in leaves and seeds, holds strong potential for commercial use in the integrated management of SPB and other lepidopteran pests.

8.
Front Plant Sci ; 14: 1165384, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37056489

RESUMO

Soybean production is severely hampered by saline-alkaline stress caused by saline-alkalization. Plants have aldehydrogenase (ALDH) family members that convert reactive aldehydes to carboxylic acids to remove active aldehyde molecules. However, little is known about the increased saline-alkali tolerance caused by the ALDH function in soybean. Here, we introduced a previously identified ALDH coding gene AhALDH3H1 from Arachis hypogaea into the soybean genome to investigate its critical role in response to saline-alkali stress. Transgenic soybean with increased aldehyde dehydrogenase activity showed significant tolerance to saline-alkali stress. It reduced malondialdehyde (MDA) content compared to its receptor, suggesting that over-expression of AhALDH3H1 accelerated soybean tolerance to saline-alkali stress by increasing aldehyde dehydrogenase activity, which is responsible for scavenging toxic MDA. To further analyze the inner mechanisms that allow transgenic plants to tolerate saline-alkali stress, we sequenced the transcriptome and metabolome of P3 (wild type, WT) and transgenic lines which were separately treated with water and a saline-alkali solution. When subjected to saline-alkali stress, the integrated analysis of the transcriptome and metabolome suggested that several genes related to cell wall structure crucial for preserving cell wall extensibility and plasticity were largely responsible for restoring homeostasis within the transgenic cells compared to WT. Metabolites, including both necessary ingredients for cell wall genesis and harmful production produced during the saline-alkali stress response, could be transported efficiently with the help of the ABC transporter, reducing the negative effects of saline-alkali stress. These findings suggest that introducing AhALDH3H1 increases transgenic soybean tolerance to saline-alkali stress may through cell wall structure maintenance and metabolites transport.

9.
Invest Ophthalmol Vis Sci ; 64(11): 23, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37589983

RESUMO

Purpose: To assess age-related biometric changes of the eye in nonhuman primates (NHPs), to and decipher the growth and aging rates and their comparability with humans. Methods: Ocular anatomic measurements were performed on 341 macaca fascicularis aged 0.5 to 23 years via multimodal approaches including IOLMaster 700. Linear or polynomial regression models were simulated to determine the best fitted age-related function. The metrics were compared with human equivalents in published reports. Results: Macaques exhibited a postnatal eye growth pattern similar to humans, characterized by continuous eye extension coordinated with dramatic reshaping of the lens but not the cornea. The age-related growth of lens thickness (LT), anterior chamber depth (ACD), and axis length (AL) exhibited nonlinear and bipolar patterns. The inflection points were 10 to 12 years old for LT and ACD and 13 to 15 years old for AL in macaques, which were comparable in chronological age at a ratio of ∼1: ratio with that in humans. In contrast, the speed of aging, including the increase in lens density and the decrease in retinal nerve fiber layer thickness, was comparable in relative age at a ratio of ∼1:3 according to the differences in lifespan between macaques and humans. Lens density was a robust indicator for the aging process. Conclusions: Macaque eyes recapitulated the age-related process of human eyes to varying extents with different growth and aging rates. Chronological age or relative age should be considered in different scenarios when macaques are included in preclinical studies.


Assuntos
Envelhecimento , Cristalino , Animais , Humanos , Criança , Córnea , Retina , Macaca fascicularis
10.
Pest Manag Sci ; 73(12): 2447-2455, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28598538

RESUMO

BACKGROUND: The soybean pod borer [SPB; Leguminivora glycinivorella (Matsumura) (Lepidoptera: Tortricidae)] is the most important soybean pest in northeastern Asia. Silencing genes using plant-mediated RNA-interference is a promising strategy for controlling SPB infestations. The ribosomal protein P0 is important for protein translation and DNA repair in the SPB. Thus, transferring P0 double-stranded RNA (dsRNA) into plants may help prevent SPB-induced damage. RESULTS: We investigated the effects of SpbP0 dsRNA injections and SpbP0 dsRNA-expressing transgenic soybean plants on the SPB. Larval mortality rates were greater for SpbP0 dsRNA-injected larvae (96%) than for the control larvae (31%) at 14 days after injections. Transgenic T2 soybean plants expressing SpbP0 dsRNA sustained less damage from SPB larvae than control plants. In addition, the expression level of the SpbP0 gene decreased and the mortality rate increased when SPB larvae were fed on T3 transgenic soybean pods. Moreover, the surviving larvae were deformed and exhibited inhibited growth. CONCLUSION: Silencing SpbP0 expression is lethal to the SPB. Transgenic soybean plants expressing SpbP0 dsRNA are more resistant to the SPB than wild-type plants. Thus, SpbP0 dsRNA-expressing transgenic plants may be useful for controlling insect pests. © 2017 Society of Chemical Industry.


Assuntos
Glycine max/parasitologia , Proteínas de Insetos/genética , Mariposas/fisiologia , Controle Biológico de Vetores/métodos , Plantas Geneticamente Modificadas/parasitologia , Proteínas Ribossômicas/genética , Animais , Expressão Gênica , Proteínas de Insetos/metabolismo , Mariposas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Interferência de RNA , RNA de Cadeia Dupla/genética , RNA de Cadeia Dupla/metabolismo , Proteínas Ribossômicas/metabolismo , Glycine max/genética , Glycine max/metabolismo
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