RESUMEN
Introduction: Grazing management is essential to maintain the stability of grassland ecosystems. Methods: To determine the optimal rest-grazing period of alpine meadow, five rest-grazing periods were set based on soil thawing and plant re-greening in this study. The niche, interspecific relationships, and stability of plant communities at different rest-grazing periods were investigated. Results: Rest-grazing during soil thawing resulted in a small niche width and niche overlap of plants, overall positive interspecific associations, and a high stability of plant communities. Delayed rest-grazing time to plant re-greening resulted in a large niche width and niche overlap of plants, overall negative interspecific associations, and a low stability of plant communities. Discussion: Rest-grazing in alpine meadows should begin as soon as possible to promote healthy and sustainable utilization of grasslands.
RESUMEN
Myeloid-derived suppressor cells (MDSCs) are recognized as major immune suppressor cells in the tumor microenvironment that may inhibit immune checkpoint blockade (ICB) therapy. Here, we developed a Stattic-loaded mesoporous silica nanoparticle (PEG-MSN-Stattic) delivery system to tumor sites to reduce the number of MDSCs in tumors. This approach is able to significantly deplete intratumoral MSDCs and thereby increase the infiltration of T lymphocytes in tumors to enhance ICB therapy. Our approach may provide a drug delivery strategy for regulating the tumor microenvironment and enhancing cancer immunotherapy efficacy.
Asunto(s)
Inmunoterapia , Células Supresoras de Origen Mieloide , Nanopartículas , Dióxido de Silicio , Microambiente Tumoral , Dióxido de Silicio/química , Nanopartículas/química , Células Supresoras de Origen Mieloide/inmunología , Células Supresoras de Origen Mieloide/efectos de los fármacos , Inmunoterapia/métodos , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/inmunología , Animales , Ratones , Porosidad , Humanos , Neoplasias/terapia , Neoplasias/inmunología , Neoplasias/tratamiento farmacológico , Línea Celular Tumoral , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Polietilenglicoles/químicaRESUMEN
INTRODUCTION: Since the discovery of gonadotropin-inhibitory hormone (GnIH), it has been found to play a critical role in reproduction in vertebrates. Recently, a regulatory role of GnIH in appetite and energy metabolism has emerged, although its precise physiological mechanisms remain unknown. METHODS: Thus, the present study evaluated the effects of a single or long-term intraperitoneal GnIH treatment on the food intake, weight, and glucolipid metabolism of chickens, as well as investigating the possible neuroendocrinology factors and mechanisms involved in GnIH-induced obesity and glucolipid metabolism disorder. RESULTS: Our results show that the intraperitoneal administration of GnIH to chickens resulted in a marked body mass increase, hyperlipidemia, hyperglycemia, and glucose intolerance. Subsequently, the results of metabolomics studies and the pharmacological inhibition of the 5-HT2C receptor revealed that blocking the 5-HT2C receptor reinforced the effects of GnIH on food intake, body weight, and blood glucose and lipid levels, resulting in even worse cases of GnIH-induced hyperglycemia, hyperlipidemia, and hepatic lipid deposition. This suggests that, via the 5-HT2C receptor, peripheral 5-HT may act as a negative feedback regulator to interplay with GnIH and jointly control energy balance homeostasis in chickens. DISCUSSION: Our present study provides evidence of cross-talk between GnIH and 5-HT in food intake and energy metabolism at the in vivo pharmacological level, and it proposes a molecular basis for these interactions, suggesting that functional interactions between GnIH and 5-HT may open new avenues for understanding the mechanism of the neuroendocrine network involved in appetite and energy metabolism, as well as providing a new therapeutic strategy to prevent obesity, diabetes, and metabolic disorders.
Asunto(s)
Pollos , Metabolismo Energético , Conducta Alimentaria , Receptor de Serotonina 5-HT2C , Serotonina , Animales , Metabolismo Energético/efectos de los fármacos , Receptor de Serotonina 5-HT2C/metabolismo , Serotonina/metabolismo , Conducta Alimentaria/efectos de los fármacos , Conducta Alimentaria/fisiología , Hormonas Hipotalámicas/metabolismo , Masculino , Glucemia/metabolismo , Glucemia/efectos de los fármacos , Hiperlipidemias/metabolismo , Hiperlipidemias/inducido químicamenteRESUMEN
Stress is known to disrupt the intestinal barrier and induce intestinal dysfunction. A critical role for gonadotropin inhibitory hormone (GnIH) in stress has emerged. However, whether GnIH mediates stress-induced intestinal dysfunction remains unknown. The present study explored this question through in vivo and in vitro experiments in hens. Our in vivo experiments showed that continuous intraperitoneal injection of GnIH not only significantly increased the concentration of stress hormones in serum, but also significantly elevated the mRNA expression of glucocorticoid receptor (GR) in the duodenum and jejunum. Moreover, morphological and molecular analyses revealed that GnIH disrupted the physical and chemical barriers of the intestine and dramatically increased inflammatory factor levels in the intestine and serum of hens. Interestingly, the microbiomics results showed that GnIH altered the structure and composition of the gut flora in the cecum, revealing an increased abundance of harmful intestinal bacteria such as Desulfovibrionaceae. Similar results were found in in vitro studies in which the GnIH-induced intestinal mucosal barrier was disrupted, and inflammation increased in jejunal explants, although no significant difference was found in the expression of GR between the control and GnIH groups. Our results demonstrated that GnIH not only directly damaged intestinal barriers and elevated intestinal inflammation but also mediated stress and microflora imbalance-induced intestinal function disorder, suggesting that GnIH is a potential therapeutic target for gut dysfunction, stress-induced intestinal function disorder, and inflammatory bowel disease in animals and humans.
Asunto(s)
Pollos , Microbioma Gastrointestinal , Estrés Fisiológico , Animales , Pollos/fisiología , Femenino , Microbioma Gastrointestinal/fisiología , Hormonas Hipotalámicas/metabolismo , Hormonas Hipotalámicas/genética , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/fisiopatología , Proteínas Aviares/metabolismo , Proteínas Aviares/genética , Enfermedades Intestinales/veterinaria , Enfermedades Intestinales/microbiologíaRESUMEN
Diabetic retinopathy (DR), a most common microangiopathy of diabetes, causes vision loss and even blindness. The mechanisms of exosomal lncRNA remain unclear in the development of DR. Here, we first identifed the pro-angiogenic effect of exosomes derived from vitreous humor of proliferative diabetic retinopathy patients, where lncRNA-MIAT was enriched inside. Secondly, lncRNA-MIAT was demonstrated significantly increased in exosomes from high glucose induced human retinal vascular endothelial cell, and can regulate tube formation, migration and proliferation ability to promote angiogenesis in vitro and in vivo. Mechanistically, the pro-angiogenic effect of lncRNA-MIAT was via the lncRNA-MIAT/miR-133a-3p/MMP-X1 axis. The reduced level of lncRNA-MIAT in this axis mitigated the generation of retinal neovascular in mouse model of oxygen-induced retinopathy (OIR), providing crucial evidence for lncRNA-MIAT as a potential clinical target. These findings enhance our understanding of the role of exosomal lncRNA-MIAT in retinal angiogenesis, and propose a promising therapeutic strategy against diabetic retinopathy.
Asunto(s)
Retinopatía Diabética , Exosomas , MicroARNs , ARN Largo no Codificante , Neovascularización Retiniana , Animales , Humanos , Masculino , Ratones , Movimiento Celular , Proliferación Celular , Células Cultivadas , Diabetes Mellitus Experimental , Retinopatía Diabética/metabolismo , Retinopatía Diabética/genética , Retinopatía Diabética/patología , Modelos Animales de Enfermedad , Exosomas/metabolismo , Exosomas/genética , Regulación de la Expresión Génica , Ratones Endogámicos C57BL , MicroARNs/genética , Neovascularización Retiniana/metabolismo , Neovascularización Retiniana/genética , Neovascularización Retiniana/patología , Vasos Retinianos/metabolismo , Vasos Retinianos/patología , ARN Largo no Codificante/genéticaRESUMEN
Land is the foundation of human life and development, which is also the most important part of a country. The study of land carrying capacity is one of the important contents of land management, wherein the evaluation of land resource carrying capacity (LRCC) is an important reference for land resource planning. Aiming at the information fuzziness and uncertainty in the evaluation of LRCC, firstly, a comprehensive evaluation model based on entropy weight and normal cloud similarity was proposed, which is based on cloud model theory and combined with normal cloud similarity measurement method and entropy weight method. Secondly, taking the asphalt pavement experiment as an example for empirical analysis, the experimental results are consistent with the actual situation, which proves the feasibility and effectiveness of the proposed model. Finally, taking China's Chongqing city as the research area, the proposed evaluation model is used to study LRCC. The research results indicate that the comprehensive carrying capacity and average carrying capacity of various systems in China's Chongqing have been improved in the past decade. Among them, the comprehensive carrying capacity rose from the second level during the "12th Five-Year Plan" period to the third level during the "13th Five-Year Plan" period. In the future, it is necessary to focus on the improvement of soil and water resources system and economic and technological system. This conclusion reflects LRCC of Chongqing in China objectively and has a reference value for Chongqing's land planning.
RESUMEN
The lens is an avascular tissue, where epithelial cells (LECs) are the primary living cells. The role of LECs-derived exosomes (LEC-exos) is largely unknown. In our study, we determined the anti-angiogenic role of LEC-exos, manifested as regressed retinal neovascularization (NV) using the oxygen-induced retinopathy (OIR), and reduced choroidal NV size and pathological vascular leakage using the laser-induced choroidal neovascularization (laser-induced CNV). Furthermore, the activation and accumulation of microglia were also restricted by LEC-exos. Based on Luminex multiplex assays, the expressions of chemokines such as SCYB16/CXCL16, MCP-1/CCL2, I-TAC/CXCL11, and MIP 3beta/CCL19 were decreased after treatment with LEC-exos. Transwell assays showed that LEC-exos restricted the migration of the mouse microglia cell line (BV2 cells). After incubation with LEC-exos-treated BV2 cells, human umbilical vein endothelial cells (hUVECs) were collected for further evaluation using tube formation, Transwell assays, and 5-ethynyl-2'-deoxyuridine (EDU) assays. Using in vitro experiments, the pro-angiogenic effect of microglia was restricted by LEC-exos. Hence, it was investigated that LEC-exos attenuated ocular NV, which might attribute to the inhibition of microglial activation and accumulation.
Asunto(s)
Neovascularización Coroidal , Exosomas , Células Madre Mesenquimatosas , Ratones , Animales , Humanos , Microglía , Exosomas/metabolismo , Angiogénesis , Neovascularización Fisiológica/fisiología , Células Endoteliales de la Vena Umbilical Humana , Neovascularización Coroidal/metabolismoRESUMEN
Diabetic retinopathy (DR) is a vision-threatening diabetic complication that is characterized by microvasculature impairment and immune dysfunction. The present study demonstrated that M2 microglia intensively participated in retinal microangiopathy in human diabetic proliferative membranes, mice retinas, retinas of mice with oxygen-induced retinopathy (OIR) mice, and retinas of streptozotocin-induced DR mice. Further in vivo and in vitro experiments showed that exosomes derived from M2 polarized microglia (M2-exo) could reduce pericyte apoptosis and promote endothelial cell proliferation, thereby promoting vascular remodeling and reducing vascular leakage from the diabetic retina. These effects were further enhanced by M2-exo that facilitated M2 polarization of retinal microglia. Collectively, the study demonstrated the capability of M2-exo to induce retinal microvascular remodeling, which may provide a new therapeutic strategy for the treatment of DR.
Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Exosomas , Ratones , Animales , Humanos , Retinopatía Diabética/tratamiento farmacológico , Retinopatía Diabética/etiología , Remodelación Vascular , Microglía , RetinaRESUMEN
Restoring vegetation in degraded ecosystems is an increasingly common practice for promoting biodiversity and ecological function, but successful implementation is hampered by an incomplete understanding of the processes that limit restoration success. By synthesizing terrestrial and aquatic studies globally (2594 experimental tests from 610 articles), we reveal substantial herbivore control of vegetation under restoration. Herbivores at restoration sites reduced vegetation abundance more strongly (by 89%, on average) than those at relatively undegraded sites and suppressed, rather than fostered, plant diversity. These effects were particularly pronounced in regions with higher temperatures and lower precipitation. Excluding targeted herbivores temporarily or introducing their predators improved restoration by magnitudes similar to or greater than those achieved by managing plant competition or facilitation. Thus, managing herbivory is a promising strategy for enhancing vegetation restoration efforts.
Asunto(s)
Biodiversidad , Restauración y Remediación Ambiental , Herbivoria , PlantasRESUMEN
Aiming at the uncertainty linguistic transformation problem in multi-attribute decision making, a decision-making method based on normal cloud similarity was proposed. Firstly, starting from the normal cloud characteristic curves, a normal cloud similarity measurement method based on Wasserstein distance is proposed by combing with the normal cloud entropy-containing expectation curve, which is using the Wasserstein distance to characterize the similarity characteristics of probability distribution. The properties of the proposed similarity measure are discussed in the paper. Secondly, the performance of the proposed method is compared and analyzed with the existed methods by numerical simulation experiment and time series data classification experiment. The experimental results show that the proposed method has good similarity discrimination ability, high classification accuracy and low CPU time cost. Finally, the method was successfully applied into linguistic multi-attribute decision making, and TOPSIS thought is used to compare and rank the schemes, so as to realize the final decision.
RESUMEN
A one-pot cascade chlorination/heterocyclization strategy has been developed for the synthesis of 2,4-dichloro-substituted quinolines from acylated anilines using triphosgene and triphenylphosphine oxide. Obviating the conventional harsh conditions of chlorination, synthetic useful quinolines with moderate to good yields were obtained through this reaction. The mechanism study exhibited that the formation of a ß-enamine intermediate plays a vital role in the generation of the final product.
RESUMEN
Introduction: Scientific grazing management is of great significance for the ecological health and sustainable use of alpine meadows. Methods: To explore appropriate management methods of alpine grasslands of the Qinghai-Tibet Plateau degraded by Achnatherum inebrians (Hance) Keng ex Tzvele presence, we studied the effects of different grazing systems on the A. inebrians population, grassland vegetation community traits, soil characteristics and soil microbial community structure for cold- season grazing plus supplementary feeding pasture (CSF) and four-season open public pasture (FOP) in Tianzhu County, Gansu Province. Results: Compared with FOP, the CSF site showed significantly inhibited reproduction of A. inebrians, especially the crown width, seed yield and number of reproductive branches per plant were as high as 50%, significantly increased the aboveground biomass of edible forage and soil water content by 57% and 43-55%, better soil nutrients, and significantly reduced soil bulk density by 10- 29%. Different grazing systems affected the composition and diversity of soil microbial communities, with a greater effect on fungi than on bacterial flora. The most abundant phyla of bacteria and fungi were Proteobacteria and Ascomycota for CSF (by 30-38% and 24-28%) and for FOP (by 67-70% and 68-73%), and the relative abundance and species of bacterial and fungal genera were greater for CSF than FOP. The α-diversity indexes of fungi were improved, and the ß-diversity of fungi was significant difference between CSF and FOP. However, the grazing utilization time was prolonged in FOP, which reduced the diversity and abundance of soil bacteria and increased soil spatial heterogeneity. The use of A. inebrians-type degraded grassland in the cold season, and as a winter supplementary feeding and resting ground, could effectively inhibit expansion of A. inebrians, promote edible forage growth, enhance grassland productivity and community stability, and improve soil structure. Discussion: The results guide healthy and sustainable utilization of A. inebrians-type degraded grassland in the Qinghai-Tibet Plateau.
RESUMEN
The use of hexachlorocyclohexanes (HCHs) in pesticides has been prohibited for decades in China. Since then, there have been urbanization and transformation of the functional areas of many sites, which were formerly involved in the HCH industry. However, it is possible that, unless properly managed, these sites may still contain HCH residues in the soil and thus pose a threat to the surrounding environment and the quality of groundwater. This study aimed to characterize soil residues in a typical site that was historically involved in HCH production in southern China, by analyzing the α-HCH, ß-HCH, and γ-HCH contents of the soil. The results suggested that HCHs persist in the environment and can have long-term effects. It was found that α-HCH and ß-HCH were present in many samples in concentrations that were comparable or higher than those specified by China's Class 1 screening values. The distribution of residues was significantly correlated with the historical HCH production activities in the areas. The characteristic ratios of α-HCH/γ-HCH and ß-HCH/(α + γ)-HCH at different soil depths were 1.4-3.7 and 0.21-1.04, respectively, which indicated the presence of significant localized residues of HCHs. The presence of HCHs in the soil suggested a downward migration, with concentrations rapidly decreasing in the upper layer soil (0-5 m), but a gradual increase in the deeper soil (5-14 m). HCHs were detected at depths exceeding 24 m, indicating heavy penetration. The proportions of γ-HCH and ß-HCH changed with increasing soil depth, which was related to their relatively volatile and stable molecular structures, respectively. The results strongly suggested that there is widespread contamination of both soil and groundwater by HCHs even after decades. The likelihood of residual HCHs in the soil should therefore be taken into full consideration during urban planning to limit risks to human and environmental health.
Asunto(s)
Agua Subterránea , Hidrocarburos Clorados , Plaguicidas , Contaminantes del Suelo , Humanos , Hexaclorociclohexano/análisis , Suelo/química , Monitoreo del Ambiente , Plaguicidas/análisis , Hidrocarburos Clorados/análisis , Contaminantes del Suelo/análisis , ChinaRESUMEN
Abnormal ocular neovascularization, a major pathology of eye diseases, leads to severe visual loss. The role of lens epithelial cell (LEC)-derived exosomes (Lec-exo) is largely unknown. Thus, we aimed to investigate whether Lec-exo can inhibit abnormal ocular neovascularization and explore the possible mechanisms. In our study, we proved the first evidence that exosomes derived from LECs attenuated angiogenesis in both oxygen-induced retinopathy and laser-induced choroidal neovascularization mice models. Further in vitro experiments proved that Lec-exo inhibited proliferation, migration, and tube formation capability of human umbilical vein endothelial cells in high glucose condition. Further high-throughput miRNAs sequencing analysis detected that miR-146a-5p was enriched in Lec-exo. Mechanistically, exosomal miR-146a-5p was delivered to endothelial cells and bound to the NRAS coding sequence, which subsequently inactivated AKT/ERK signaling pathway. We successfully elucidated the function of Lec-exo in inhibiting abnormal ocular neovascularization, which may offer a promising strategy for treatment of abnormal ocular neovascularization.
Asunto(s)
Neovascularización Coroidal , Exosomas , MicroARNs , Humanos , Animales , Ratones , Células Epiteliales , Neovascularización Coroidal/genética , Células Endoteliales de la Vena Umbilical Humana , MicroARNs/genéticaRESUMEN
Diabetic retinopathy (DR), one of the most common microangiopathic complications in diabetes, causes severe visual damage among working-age populations. Retinal vascular endothelial cells, the key cell type in DR pathogenesis, are responsible for abnormal retinal angiogenesis in advanced stages of DR. The roles of exosomes in DR have been largely unknown. In this study, we report the first evidence that exosomes derived from the vitreous humor of patients with proliferative DR (PDR-exo) promote proliferation, migration, and tube formation of human retinal vascular endothelial cells (HRVECs). We identified long noncoding RNA (lncRNA) LOC100132249 enrichment in PDR-exo via high-throughput sequencing. This lncRNA, also mainly derived from HRVECs, promoted angiogenesis both in vitro and in vivo. Mechanistically, LOC100132249 acted as a competing endogenous sponge of miRNA-199a-5p (miR-199a-5p), thus regulating the endothelial-mesenchymal transition promoter SNAI1 via activation of the Wnt/ß-catenin pathway and ultimately resulting in endothelial dysfunction. In conclusion, our findings underscored the pathogenic role of endothelial-derived exosomes via the LOC100132249/miR-199a-5p/SNAI1 axis in DR angiogenesis and may shed light on new therapeutic strategies for future treatment of DR. ARTICLE HIGHLIGHTS: This study provides the first evidence that exosomes derived from vitreous humor from patients with proliferative diabetic retinopathy participate in angiogenesis. The findings demonstrate an unreported long noncoding RNA (lncRNA), LOC100132249, by exosomal sequencing of vitreous humor. The newly found lncRNA LOC100132249, mainly derived from endothelial cells, promotes angiogenesis via an miRNA-199a-5p/SNAI1/Wnt/ß-catenin axis in a pro-endothelial-mesenchymal transition manner.
Asunto(s)
Retinopatía Diabética , Exosomas , MicroARNs , ARN Largo no Codificante , Humanos , beta Catenina/metabolismo , Proliferación Celular/genética , Diabetes Mellitus/metabolismo , Retinopatía Diabética/metabolismo , Células Endoteliales/metabolismo , Exosomas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismoRESUMEN
Apart from the well-established role of the gonadotropin-inhibitory hormone (GnIH) in the regulation of the reproductive functions, much less is known about the peripheral role of the GnIH and its receptor in the metabolic processes. On account of pig being an excellent model for studies of food intake and obesity in humans, we investigated the peripheral effects of the GnIH on food intake and energy homeostasis and revealed the underlying mechanism(s) in female piglets in vivo. Compared to the vehicle-treated group, intraperitoneally injected GnIH significantly increased the food intake and altered the meal microstructure both in the fasting and ad libitum female piglet. GnIH-triggered hyperphagia induced female piglet obesity and altered islet hormone secretion in the pancreas, accompanied with dyslipidemia and hyperglycemia. Interestingly, GnIH decreased the glucose transport capacity and glycogen synthesis, whereas it increased the gluconeogenesis in the liver, while it also induced an insulin resistance in white adipose tissue (WAT) via inhibiting the activity of AKT-GSK3-ß signaling. In terms of the lipid metabolism, GnIH reduced the oxidation of fatty acids, whereas the elevated fat synthesis ability in the liver and WAT was developed though the inhibited AMPK phosphorylation. Our findings demonstrate that peripheral GnIH could trigger hyperphagia-induced obesity and an associated glycolipid metabolism disorder in female piglets, suggesting that GnIH may act as a potential therapeutic agent for metabolic syndrome, obesity and diabetes.
Asunto(s)
Hormonas Hipotalámicas , Humanos , Animales , Femenino , Porcinos , Hormonas Hipotalámicas/fisiología , Glucógeno Sintasa Quinasa 3 , Gonadotropinas , Hiperfagia , Obesidad/etiologíaRESUMEN
Gonadotropin-inhibitory hormone (GnIH) is a reproductive inhibitor and an endogenous orexigenic neuropeptide that may be involved in energy homeostasis and reproduction. However, whether GnIH is a molecular signal link of metabolism and the reproductive system, and thus, regulates reproductive activity as a function of the energy state, is still unknown. In the present study, we investigated the involvement of GnIH in glycolipid metabolism and reproduction in vivo, and in the coupling between these two processes in the testis level. Our results showed that chronic intraperitoneal injection of GnIH into male mice not only increased food intake and altered meal microstructure but also significantly elevated body mass due to the increased mass of liver and epididymal white adipose tissue (eWAT), despite the loss of testicular weight. Furthermore, chronic intraperitoneal administration of GnIH to male mice resulted in obesity-related glycolipid metabolic derangements, showing hyperlipidemia, hyperglycemia, glucose intolerance, and insulin resistance through changes in the expression of glucose and lipid metabolism-related genes in the pancreas and eWAT, respectively. Interestingly, the expression of GnIH and GPR147 was markedly increased in the testis of mice under conditions of energy imbalance, such as fasting, acute hypoglycemia, and hyperglycemia. In addition, chronic GnIH injection markedly inhibited glucose and lipid metabolism of mice testis while significantly decreasing testosterone synthesis and sperm quality, inducing hypogonadism. These observations indicated that orexigenic GnIH triggers hyperphagia-induced obesity-related metabolic derangements and hypogonadism in male mice, suggesting that GnIH is an emerging candidate for coupling metabolism and fertility by involvement in obesity and metabolic disorder-induced reproductive dysfunction of the testes.
Asunto(s)
Hiperglucemia , Hipogonadismo , Hormonas Hipotalámicas , Animales , Glucosa , Glucolípidos , Gonadotropinas , Hiperfagia/complicaciones , Hipogonadismo/etiología , Hormonas Hipotalámicas/genética , Masculino , Ratones , Obesidad/complicaciones , Semen/metabolismoRESUMEN
This study aimed to investigate the inhibitory effect and mechanism of Cucurbitacin I (Cu I) on apoptosis, oxidative stress, and mitophagy in PC12 cells with glucose and oxygen deprivation/reperfusion (OGD/RP) injury. OGD/RP cell injury model was established by gas anoxic cell incubator and glucose-free medium. The cells were divided into the control group, OGD/RP group, OGD/RP + Cu I group, and OGD/RP + Cu I + 2 µM nuclear factor erythroid 2-related factor 2 (Nrf2) inhibitor ML385 group. The results showed that apoptotic rate and reactive oxygen species (ROS) production were significantly increased in OGD/RP group, which were reversed by Cu I pretreatment. Meanwhile, western blot analysis proved that Cu I inhibited OGD/RP-induced mitophagy, manifested as the decreased expression of PTEN-induced kinase 1 (PINK1) and parkin RBR E3 ubiquitin-protein ligase (Parkin), and light chain 3 (LC3) â ¡∕LC3 I, as well as the increased expression of P62. Furthermore, immunofluorescence (IF) staining showed that Cu I reduced the co-localized puncta of LC3 with TOM20 in OGD/RP-induced PC12 cells. Similarly, transmission electron microscope finding is consistent with the IF results. Mechanically, after Cu I and OGD/RP treatments, nuclear Nrf2 expression and the levels of downstream target genes were significantly upregulated compared with OGD/RP alone treatment. Nrf2 inhibition reversed the protective effects of Cu I on OGD/RP-induced injury in PC12 cells. The present study provides evidence of the neuroprotective effect of Cu I unraveling its potential as a potential therapeutic candidate for the treatment of ischemic stroke.
Asunto(s)
Elementos de Respuesta Antioxidante , Daño por Reperfusión , Animales , Glucosa/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Neuronas/metabolismo , Oxígeno/metabolismo , Ratas , Reperfusión , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/metabolismo , Triterpenos , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/farmacologíaRESUMEN
The world has increasingly relied on protected areas (PAs) to rescue highly valued ecosystems from human activities, but whether PAs will fare well with bioinvasions remains unknown. By analyzing three decades of seven of the largest coastal PAs in China, including World Natural Heritage and/or Wetlands of International Importance sites, we show that, although PAs are achieving success in rescuing iconic wetlands and critical shorebird habitats from once widespread reclamation, this success is counteracted by escalating plant invasions. Plant invasions were not only more extensive in PAs than non-PA controls but also undermined PA performance by, without human intervention, irreversibly replacing expansive native wetlands (primarily mudflats) and precluding successional formation of new native marshes. Exotic species are invading PAs globally. This study across large spatiotemporal scales highlights that the consequences of bioinvasions for humanity's major conservation tool may be more profound, far reaching, and critical for management than currently recognized.
RESUMEN
Despite escalating anthropogenic alteration of food webs, how the carbon cycle in ecosystems is regulated by food web processes remains poorly understood. We quantitatively synthesize the effects of consumers (herbivores, omnivores and carnivores) on the carbon cycle of coastal wetland ecosystems, 'blue carbon' ecosystems that store the greatest amount of carbon per unit area among all ecosystems. Our results reveal that consumers strongly affect many processes of the carbon cycle. Herbivores, for example, generally reduce carbon absorption and carbon stocks (e.g. aboveground plant carbon by 53% and aboveground net primary production by 23%) but may promote some carbon emission processes (e.g. litter decomposition by 32%). The average strengths of these effects are comparable with, or even times higher than, changes driven by temperature, precipitation, nitrogen input, CO2 concentration, and plant invasions. Furthermore, consumer effects appear to be stronger on aboveground than belowground carbon processes and vary markedly with trophic level, body size, thermal regulation strategy and feeding type. Despite important knowledge gaps, our results highlight the powerful impacts of consumers on the carbon cycle and call for the incorporation of consumer control into Earth system models that predict anthropogenic climate change and into management strategies of Earth's carbon stocks. This article is part of the theme issue 'Integrative research perspectives on marine conservation'.