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1.
NLRP3 inflammasome activation plays an important role in diabetic cardiomyopathy (DCM), which may relate to excessive production of reactive oxygen species (ROS). Gypenosides (Gps), the major ingredients of Gynostemma pentaphylla (Thunb.) Makino, have exerted the properties of anti‐hyperglycaemia and anti‐inflammation, but whether Gps improve myocardial damage and the mechanism remains unclear. Here, we found that high glucose (HG) induced myocardial damage by activating the NLRP3 inflammasome and then promoting IL‐1β and IL‐18 secretion in H9C2 cells and NRVMs. Meanwhile, HG elevated the production of ROS, which was vital to NLRP3 inflammasome activation. Moreover, the ROS activated the NLRP3 inflammasome mainly by cytochrome c influx into the cytoplasm and binding to NLRP3. Inhibition of ROS and cytochrome c dramatically down‐regulated NLRP3 inflammasome activation and improved the cardiomyocyte damage induced by HG, which was also detected in cells treated by Gps. Furthermore, Gps also reduced the levels of the C‐reactive proteins (CRPs), IL‐1β and IL‐18, inhibited NLRP3 inflammasome activation and consequently improved myocardial damage in vivo. These findings provide a mechanism that ROS induced by HG activates the NLRP3 inflammasome by cytochrome c binding to NLRP3 and that Gps may be potential and effective drugs for DCM via the inhibition of ROS‐mediated NLRP3 inflammasome activation.  相似文献   

2.
The structural similarities between N1 substituted 1,4‐dihydropyridines and the known gp41 inhibitors, NB ‐2 and NB ‐64 , were considered in the current research for the design of some novel anti‐HIV‐1 agents. A series of novel 4‐[4‐arylpyridin‐1(4H)‐yl]benzoic acid derivatives were synthesized and after a comprehensive structural elucidation were screened for in vitro anti‐HIV‐1 activity. Most of the tested compounds displayed moderate to good inhibitory activity against HIV‐1 growth and were evaluated for in vitro cytotoxic activity using XTT assay at the concentration of 100 μm . Among the tested compounds, 1c , 1d and 1e showed potent anti‐HIV‐1 activity against P24 expression at 100 μm with inhibition percentage of 84.00%, 76.42% and 80.50%, respectively. All the studied compounds possessed no significant cytotoxicity on MT‐2 cell line. The binding modes of these compounds to gp41 binding site were determined through molecular docking study. Docking studies proved 1a as the most potent compound and binding maps exhibited that the activities might be attributed to the electrostatic and hydrophobic interactions and additional H‐bonds with the gp41 binding site. The Lipinski's ‘rule of five’ and drug‐likeness criteria were also calculated for the studied compounds. All derivatives obeyed the Lipinski's ‘rule of five’ and had drug‐like features. The findings of this study suggest that novel 4‐[4‐arylpyridin‐1(4H)‐yl]benzoic acid might be a promising scaffold for the discovery and development of novel anti‐HIV‐1 agents.  相似文献   

3.
1. Foliar colour changes with age and, as a consequence, reflects the internal physiology of leaves. Anthocyanins are ‘red’ pigments known for their photoprotective role in young leaves and have been suggested to influence the host‐finding behaviour of insect herbivores. The existence of colour vision in some species of Eucalyptus‐feeding psyllid provides evidence for the possibility of them being able to locate and select leaves based on their age. 2. The preferences of three psyllid species, namely Anoeconeossa bundoorensis, Glycaspis brimblecombei, and Ctenarytaina bipartita, for leaf colours were tested using live leaves of different age, presented without olfactory cues. Changes in foliar pigment concentrations and relationships with amino acid composition in these psyllid's hosts, namely Eucalyptus camaldulensis and Eucalyptus kitsoniana, were studied to consider the adaptive significance of selecting leaves based on their age. 3. The preference for and attraction to young, anthocyanic leaves of two red‐sensitive psyllid species (A. bundoorensis and G. brimblecombei) were demonstrated, whilst the green‐yellow‐sensitive species (C. bipartita) was shown to discriminate between young ‘yellow’ and older ‘green’ leaves. Age‐related variation in leaf colour was positively correlated with greater availability of essential amino acids. 4. This study presents a unique example of herbivore attraction to ‘red’ leaves and strong evidence for reliance on colour vision in insect orientation at the within‐host level.  相似文献   

4.
The analysis of age‐specific mortality can yield insights into how anti‐aging interventions operate that cannot be matched by simple assessment of longevity. Mortality, as opposed to longevity, can be used to assess the effects of an anti‐aging intervention on a daily basis, rather than only after most animals have died. Various gerontogene mutations in Caenorhabditis elegans have been shown to increase longevity as much as tenfold and to decrease mortality at some ages even more. Environmental alterations, such as reduced food intake (dietary restriction) and lower temperature also result in reduced mortality soon after the intervention. Here, we ask how soon anti‐aging interventions, applied during adult life, affect age‐specific mortality in nematodes. Using maximum likelihood analysis, we estimated the Gompertz parameters after shifts of temperature, and of food concentration and maintenance conditions. In separate experiments, we altered expression of age‐1 and daf‐16, using RNAi. Using about 44 000 nematodes in total, to examine daily mortality, we find that for both types of environmental shift, mortality responded immediately in the first assessment, while RNAi‐induced changes resulted in a slower response, perhaps due to delayed mechanics of RNAi action. However, under all conditions there is a permanent ‘memory’ of past states, such that the initial mortality component [a] of the Gompertz equation [μ(x) = aebx] bears a permanent ‘imprint’ of that earlier state. However, ‘b’ (the rate of mortality increase with age) is always specified by the current conditions.  相似文献   

5.
Anthrax lethal toxin (LT) rapidly kills macrophages from certain mouse strains in a mechanism dependent on the breakdown of unknown protein(s) by the proteasome, formation of the Nalp1b (NLRP1b) inflammasome and subsequent activation of caspase‐1. We report that heat‐shocking LT‐sensitive macrophages rapidly protects them against cytolysis by inhibiting caspase‐1 activation without upstream effects on LT endocytosis or cleavage of the toxin's known cytosolic substrates (mitogen‐activated protein kinases). Heat shock protection against LT occurred through a mechanism independent of de novo protein synthesis, HSP90 activity, p38 activation or proteasome inhibition and was downstream of mitogen‐activated protein kinase cleavage and degradation of an unknown substrate by the proteasome. The heat shock inhibition of LT‐mediated caspase‐1 activation was not specific to the Nalp1b (NLRP1b) inflammasome, as heat shock also inhibited Nalp3 (NLRP3) inflammasome‐mediated caspase‐1 activation in macrophages. We found that heat shock induced pro‐caspase‐1 association with a large cellular complex that could prevent its activation. Additionally, while heat‐shocking recombinant caspase‐1 did not affect its activity in vitro, lysates from heat‐shocked cells completely inhibited recombinant active caspase‐1 activity. Our results suggest that heat shock inhibition of active caspase‐1 can occur independently of an inflammasome platform, through a titratable factor present within intact, functioning heat‐shocked cells.  相似文献   

6.
Nearly 263 000 individual length–weight (L/W) data, collected during 2839 fish stock assessments between 1992 and 2009, were used to calculate L/W relationships (W = aLb) of 40 freshwater fish species from Flanders (Belgium). Roach Rutilus rutilus, perch Perca fluviatilis, three‐spine stickleback Gasterosteus aculeatus, gudgeon Gobio gobio and European eel Anguilla anguilla were the most abundant species in our surveys. Mean a and b values were in accordance with those available in FishBase. Mean b across all examined species is 3.094 (95% CL = 3.041 to 3.148) indicating a tendency towards slightly positive allometric growth in most fishes (thirty‐three species with b > 3). On the basis of a form factor equation, we characterized 2 species as ‘eel‐like’, 7 as ‘elongated’, 22 as ‘fusiform’ and 9 species as ‘short and deep’. This paper adds a substantial dataset to the yet scarcely available a and b values of European populations of freshwater fish species.  相似文献   

7.
8.
This research was carried out to study phytochemical profile, in vitro antioxidant capacity, reducing power, anti‐hyperglycemic, anti‐inflammatory activities and simulated gastrointestinal digestion of 7‐day old cereal sprouts: spelt wheat ‘Nirvana’ (WSSpe), wheat ‘Simonida’ (WSSim), oat ‘Golozrni’ (OSG) and oat ‘Jadar’ (OSJ). OSG expressed significantly higher ( 0.05) total phenols (TPC) and flavonoids content (TFC), antioxidant capacities (DPPH and ABTS assays) and reducing power (EC50DPPH = 2.12 mg/ml; EC50ABTS = 0.87 mg/ml; EC0.5RP = 12.24 mg/ml) as well as anti‐hyperglycemic activity (EC50AHgA = 0.96 mg/ml). WSSpe had the highest content of chlorophyll (131.23 mg/100 g) and carotenoids (22.84 mg/100 g). WSSim possessed the most potent anti‐inflammatory activity (2.71 mg/ml), though not significantly different from OSG (2.77 mg/ml). The in vitro simulation of gastro‐intestinal digestion showed higher release of phenolic compounds in intestinal than in gastric fluid.  相似文献   

9.
Interleukin (IL)‐1β plays an important role in the pathogenesis of idiopathic pulmonary fibrosis. The production of IL‐1β is dependent upon caspase‐1‐containing multiprotein complexes called inflammasomes and IL‐1R1/MyD88/NF‐κB pathway. In this study, we explored whether a potential anti‐fibrotic agent fluorofenidone (FD) exerts its anti‐inflammatory and anti‐fibrotic effects through suppressing activation of NACHT, LRR and PYD domains‐containing protein 3 (NALP3) inflammasome and the IL‐1β/IL‐1R1/MyD88/NF‐κB pathway in vivo and in vitro. Male C57BL/6J mice were intratracheally injected with Bleomycin (BLM) or saline. Fluorofenidone was administered throughout the course of the experiment. Lung tissue sections were stained with haemotoxylin and eosin and Masson's trichrome. Cytokines were measured by ELISA, and α‐smooth muscle actin (α‐SMA), fibronectin, collagen I, caspase‐1, IL‐1R1, MyD88 were measured by Western blot and/or RT‐PCR. The human actue monocytic leukaemia cell line (THP‐1) were incubated with monosodium urate (MSU), with or without FD pre‐treatment. The expression of caspase‐1, IL‐1β, NALP3, apoptosis‐associated speck‐like protein containing (ASC) and pro‐caspase‐1 were measured by Western blot, the reactive oxygen species (ROS) generation was detected using the Flow Cytometry, and the interaction of NALP3 inflammasome‐associated molecules were measured by Co‐immunoprecipitation. RLE‐6TN (rat lung epithelial‐T‐antigen negative) cells were incubated with IL‐1β, with or without FD pre‐treatment. The expression of nuclear protein p65 was measured by Western blot. Results showed that FD markedly reduced the expressions of IL‐1β, IL‐6, monocyte chemotactic protein‐1 (MCP‐1), myeloperoxidase (MPO), α‐SMA, fibronectin, collagen I, caspase‐1, IL‐1R1 and MyD88 in mice lung tissues. And FD inhibited MSU‐induced the accumulation of ROS, blocked the interaction of NALP3 inflammasome‐associated molecules, decreased the level of caspase‐1 and IL‐1β in THP‐1 cells. Besides, FD inhibited IL‐1β‐induced the expression of nuclear protein p65. This study demonstrated that FD, attenuates BLM‐induced pulmonary inflammation and fibrosis in mice via inhibiting the activation of NALP3 inflammasome and the IL‐1β/IL‐1R1/MyD88/ NF‐κB pathway.  相似文献   

10.
Legionella pneumophila has become a model system to decipher the non‐apoptotic functions of caspases and their role in immunity. In permissive cells, the L. pneumophila‐containing vacuole evades endosomal traffic and is remodelled by the endoplasmic reticulum. Evasion of the endosomes is mediated by the Dot/Icm type IV secretion system. Upon L. pneumophila infection of genetically restrictive cells such as wild‐type (WT) C57Bl/6J murine macrophages, flagellin is sensed by the NOD‐like receptor Nlrc4 leading to caspase‐1 activation by the inflammasome complex. Then, caspase‐7 is activated downstream of the Nlrc4 inflammasome, promoting non‐apoptotic functions such as L. pneumophila‐containing phagosome maturation and bacterial degradation. Interestingly, caspase‐3 is activated in permissive cells during early stages of infection. However, caspase‐3 activation does not lead to apoptosis until late stages of infection because it is associated with potent Dot/Icm‐mediated anti‐apoptotic stimuli that render the infected cells resistant to external apoptotic inducers. Therefore, the role of caspase‐1 and non‐apoptotic functions of executioner caspases are temporally and spatially modulated during infection by L. pneumophila, which determine permissiveness to intracellular bacterial proliferation. This review will examine the novel activation pathways of caspases by L. pneumophila and discuss their role in genetic restriction and permissiveness to infection.  相似文献   

11.
The skulls of 33 extant cat species were characterized through three‐dimensional geometric morphometrics using 20 landmarks. A principal component analysis (PCA) was performed with Procrustes fitted coordinates, and the PC‐scores were phylogenetically corrected by independent contrasts method. Three PCs allowed for the definition of five cat skull patterns. PC1: ‘snouted/massive‐headed cats’ (genus Panthera) opposing the ‘round‐headed small cats’ (genus Oncifelis, Prionailurus rubiginosus, Prionailurus bengalensis, among other small cats); PC2: ‘tapering‐headed cats’ (Neofelis nebulosa, Herpailurus yagouaroundi, Prionailurus planiceps) opposing the ‘stout‐headed cats’ (Acinonyx jubatus, Uncia uncia, Otocolobus manul, Felis margarita, and Felis nigripes); and PC3: ‘low profiled‐headed cats’ (mostly, Pr. planiceps). A sixth pattern, the ‘generalized skull’, observed in the Caracal lineage, genus Lynx, Leopardus pardalis, and Catopuma temminckii, indicates a morphological convergence among midsized‐cats. The morphological trends ‘snouted/massive’ and ‘round’ clearly denote a co‐evolution between size and shape. The other skull patterns evolved unrelatedly to the size (i.e. their allometric variations are not a size function). Nevertheless, each species comprises an amalgam of these patterns, so the influence of the size permeates, in some extent, the skull morphology along all cat lineages. The felid ecomorphological fit to hypercarnivory is obvious; however, different skull shapes in same‐sized species with similar habits, indicate that the variation in the skull morphology may result from phenotypic fluctuations, whose adaptive value (if indeed there is any) is still obscure. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103 , 176–190.  相似文献   

12.
The Salmoniform whole‐genome duplication is hypothesized to have facilitated the evolution of anadromy, but little is known about the contribution of paralogs from this event to the physiological performance traits required for anadromy, such as salinity tolerance. Here, we determined when two candidate, salinity‐responsive paralogs of the Na+, K+ ATPase α subunit (α1a and α1b) evolved and studied their evolutionary trajectories and tissue‐specific expression patterns. We found that these paralogs arose during a small‐scale duplication event prior to the Salmoniform, but after the teleost, whole‐genome duplication. The ‘freshwater paralog’ (α1a) is primarily expressed in the gills of Salmoniformes and an unduplicated freshwater sister species (Esox lucius) and experienced positive selection in the freshwater ancestor of Salmoniformes and Esociformes. Contrary to our predictions, the ‘saltwater paralog’ (α1b), which is more widely expressed than α1a, did not experience positive selection during the evolution of anadromy in the Coregoninae and Salmonine. To determine whether parallel mutations in Na+, K+ ATPase α1 may contribute to salinity tolerance in other fishes, we studied independently evolved salinity‐responsive Na+, K+ ATPase α1 paralogs in Anabas testudineus and Oreochromis mossambicus. We found that a quarter of the mutations occurring between salmonid α1a and α1b in functionally important sites also evolved in parallel in at least one of these species. Together, these data argue that paralogs contributing to salinity tolerance evolved prior to the Salmoniform whole‐genome duplication and that strong selection and/or functional constraints have led to parallel evolution in salinity‐responsive Na+, K+ ATPase α1 paralogs in fishes.  相似文献   

13.
Described and illustrated is Warneckea cordiformis R. D. Stone, an evidently localized endemic of coastal dry forest in Mozambique's Cabo Delgado Province. In ‘Flora Zambesiaca’ the new species would key to W. sansibarica (Taub.) Jacq.‐Fél., from which it is readily distinguished by the much smaller, ovate to cordiform leaves and white, short‐pedicellate flowers. Because of its evidently very limited occurrence as well as on‐going anthropogenic threats, Warneckea cordiformis is here assessed as ‘Critically Endangered’ (CR) B1a,b(iii) according to IUCN criteria. A key is provided to the Mozambican species of Warneckea.  相似文献   

14.
Abstract 1. It has become apparent that predators may strongly decrease prey fitness without direct contact with the prey, as they induce the development of defence systems that limit the availability of energy for growth and reproduction. Recent studies suggest that stress proteins may help prey organisms deal with this stress. The pattern is not general, however, and little is known about species differences in physiological traits in coping with predator stress, and covariation of physiological with other antipredator traits. 2. To explore these issues, we quantified levels of constitutive and fish‐induced stress proteins (Hsp60 and Hsp70) and anti‐predator behaviours in larvae of two damselfly species that differ in lifestyle. Both stress proteins were fixed at higher levels in Erythromma najas, which has a slow lifestyle, than in Lestes sponsa, which has a fast lifestyle. Similarly, anti‐predator behaviours were fixed at safer levels in E. najas than in L. sponsa. 3. These results suggest that stress proteins may be part of anti‐predator syndromes of damselfly larvae, and there may be trait co‐specialisation between stress proteins and behavioural anti‐predator traits. Studies formally testing these hypotheses in more species may prove rewarding in advancing our understanding of the functional integration of physiological anti‐predator traits in relation to the prey’s lifestyle.  相似文献   

15.
The turtles of the Purbeck Limestone Group of Dorset, southern England   总被引:1,自引:0,他引:1  
The turtles from the Purbeck Limestone are revised and it is concluded that there are four shell‐based cryptodire species present, namely Pleurosternon bullockii, ‘Glyptopstypocardium comb. nov., Helochelydra anglica comb. nov.,Hylaeochelys latiscutata. There is also one skull‐based species, Dorsetochelys delairi, which may prove to be the skull of ‘Glyptops’, Hylaeochelys or an unknown shell‐type. All other taxa are junior synonyms except ‘Cheloneobovata Owen, 1842 and Tretosternon punctatum Owen, 1842 which are nomina dubia, the material being unfigured and either lost or incorrectly associated. Other taxonomic conclusions are that (1) because Tretosternon is a nomen dubium, the next senior name for this Purbeck–Wealden genus is Helochelydra Nopcsa, 1928; (2) ‘Pleurosternontypocardium and ‘Glyptopsruetimeyeri are synonymous, the senior combination being ‘Glyptopstypocardium; (3) the Purbeck ‘Tretosternon’ material is combined with the holotype and only specimen of Platychelys? anglica as Helochelydra anglica comb. nov.; (4) Hylaeochelys emarginata and H. sollasi are junior synonyms of Hylaeochelys latiscutata; (5) one of Owen's ‘lost’ syntypes of ‘Tretosternon punctatum’ has been recognised and is a plastron of Hylaeochelys latiscutata.  相似文献   

16.
The inflammasome is a multiprotein complex that mediates caspase‐1 activation with subsequent maturation of the proinflammatory cytokines IL‐1β and IL‐18. The NLRP3 inflammasome is known to be activated by Staphylococcus aureus, one of the leading causes of bacteremia worldwide. Inflammasome activation and regulation in response to bacterial infection have been found to be of importance for a balanced host immune response. However, inflammasome signaling in vivo in humans initiated by S. aureus is currently sparsely studied. This study therefore aimed to investigate NLRP3 inflammasome activity in 20 patients with S. aureus bacteremia (SAB), by repeated measurement during the first week of bacteremia, compared with controls. Caspase‐1 activity was measured in monocytes and neutrophils by flow cytometry detecting FLICA (fluorescent‐labeled inhibitor of caspase‐1), while IL‐1β and IL‐18 was measured by Luminex and ELISA, respectively. As a measure of inflammasome priming, messenger RNA (mRNA) expression of NLRP3, CASP1 (procaspase‐1), and IL1B (pro‐IL‐1β) was analyzed by quantitative PCR. We found induced caspase‐1 activity in innate immune cells with subsequent release of IL‐18 in patients during the acute phase of bacteremia, indicating activation of the inflammasome. There was substantial interindividual variation in caspase‐1 activity between patients with SAB. We also found an altered inflammasome priming with low mRNA levels of NLRP3 accompanied by elevated mRNA levels of IL1B. This increased knowledge of the individual host immune response in SAB could provide support in the effort to optimize management and treatment of each individual patient.  相似文献   

17.
18.
The goal of this study was to investigate whether chilling tolerance of C4 photosynthesis in Miscanthus can be transferred to sugarcane by hybridization. Net leaf CO2 uptake (Asat) and the maximum operating efficiency of photosystem II (ФPSII) were measured in warm conditions (25 °C/20 °C), and then during and following a chilling treatment of 10 °C/5 °C for 11 day in controlled environment chambers. Two of three hybrids (miscanes), ‘US 84‐1058’ and ‘US 87‐1019’, did not differ significantly from the chilling tolerant M. ×giganteus ‘Illinois’ (Mxg), for Asat, and ΦPSII measured during chilling. For Mxg grown at 10 °C/5 °C for 11 days, Asat was 4.4 μmol m?2 s?1, while for miscane ‘US 84‐1058’ and ‘US 87‐1019’, Asat was 5.7 and 3.5 μmol m?2 s?1, respectively. Miscanes ‘US 84‐1058’ and ‘US 87‐1019’ and Mxg had significantly higher rates of Asat during chilling than three tested sugarcanes. A third miscane showed lower rates than Mxg during chilling, but recovered to higher rates than sugarcane upon return to warm conditions. Chilling tolerance of ‘US 84‐1058’ was further confirmed under autumn field conditions in southern Illinois. The selected chilling tolerant miscanes have particular value for biomass feedstock and biofuel production and at the same time they can be a starting point for extending sugarcane's range to colder climates.  相似文献   

19.
During the 2012 and 2013 growing seasons, a disease was detected on potted laurustinus (Viburnum tinus) plants in two nurseries located in the Catania province (eastern Sicily, Italy). ‘Cylindrocarpon’‐like species were consistently recovered from crown rot and stem rot tissues. Based on morphological characteristics, DNA sequencing and phylogenetic analysis of β‐tubulin (TUB), histone H3 (HIS3) and translation elongation factor‐1α (TEF‐1 α) gene sequences, the fungi associated with symptomatic tissues were identified as ‘Cylindrocarponpauciseptatum, Ilyonectria novozelandica and I. torresensis. Koch's postulates were fulfilled by pathogenicity tests carried out on potted V. tinus cuttings. To our knowledge, this is the first report worldwide of ‘C.’ pauciseptatum, Inovozelandica and Itorresensis causing disease on V. tinus.  相似文献   

20.
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