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On deflationary accounts of human action understanding
A common deflationary tendency has emerged recently in both philosophical accounts and comparative animal studies concerned with how subjects understand the actions of others. The suggestion emerging from both arenas is that the default mechanism for understanding action involves only a sensitivity to the observable, behavioural (non-mental) features of a situation. This kind of ‘smart behaviour reading’ thus suggests that, typically, predicting or explaining the behaviour of conspecifics does not require seeing the other through the lens of mental state attribution. This paper aims to explore and assess this deflationary move. In §1 I clarify what might be involved in a smart behaviour reading account via looking at some concrete examples. Then in §2 I critically assess the deflationary move, arguing that, at least in the human case, it would in fact be a mistake to assume that our default method of action understanding proceeds without appeal to mental state attribution. Finally in §3 I consider briefly how the positive view proposed here relates to discussions about standard two-system models of cognition
Antimalarial drug artemether inhibits neuroinflammation in BV2 microglia through Nrf2-dependent mechanisms
Artemether, a lipid-soluble derivative of artemisinin has been reported to possess anti-inflammatory properties. In this study, we have investigated the molecular mechanisms involved in the inhibition of neuroinflammation by the drug. The effects of artemether on neuroinflammation-mediated HT22 neuronal toxicity were also investigated in a BV2 microglia/HT22 neuron co-culture. To investigate effects on neuroinflammation, we used LPS-stimulated BV2 microglia treated with artemether (5-40µM) for 24 hours. ELISAs and western blotting were used to detect pro inflammatory cytokines, nitric oxide, PGE2, iNOS, COX-2 and mPGES-1. BACE-1 activity and Aβ levels were measured with ELISA kits. Protein levels of targets in NF-kappaB and p38 MAPK signalling, as well as HO-1, NQO1 and Nrf2 were also measured with western blot. NF-kappaB binding to the DNA was investigated using EMSA. MTT, DNA fragmentation and ROS assays in BV2-HT22 neuronal co-culture were used to evaluate the effects of artemether on neuroinflammation-induced neuronal death. The role of Nrf2 in the anti-inflammatory activity of artemether was investigated in BV2 cells transfected with Nrf2 siRNA. Artemether significantly suppressed pro-inflammatory mediators (NO/iNOS, PGE2/COX-2/mPGES-1, TNFα, and IL-6), Aβ and BACE-1 in BV2 cells following LPS stimulation. These effects of artemether were shown to be mediated through inhibition of NF-kappaB and p38MAPK signalling. Artemether produced increased levels of HO-1, NQO1 and GSH in BV2 microglia. The drug activated Nrf2 activity by increasing nuclear translocation of Nrf2 and its binding to antioxidant response elements in BV2 cells. Transfection of BV2 microglia with Nrf2 siRNA resulted in the loss of both anti-inflammatory and neuroprotective activities of artemether. We conclude that artemether induces Nrf2 expression and suggest that Nrf2 mediates the anti-inflammatory effect of artemether in BV2 microglia. Our results suggest that this drug has a therapeutic potential in neurodegenerative disorders
Effects of important plant species of Teruel on the pro-inflamatory signalling cascade of human monocytes
Background: The study of medicinal and edible plants from Teruel (Spain) –one of the biodiverse regions of the Mediterranean has been particularly limited tothe write-up of taxonomical databases and lists of protected species. The following analysis and work will be the first for this region and will focus on the anti-inflammatory activity of plant species, based on information gained through knowledge oftheir traditional use. Aims: Touse a multitarget, in vitroapproach focusing on the antioxidant and pro-inflammatory signalling cascade. To provide a phytochemical basis to the traditional and oral traditions of ethnographic research. Methods: Plants extracts (1-50 μg/mL)from Teruel recorded as traditionallyusedagainst indicationsrelated to inflammation were assessed as potential inhibitors of the release of inflammatory mediators namely interleukin (IL)-6, IL-8, tumour necrosis factor (TNF)-alpha) and prostaglandin (PG) E2 in primary human monocytes challenged with 10 ng/mL of LPS. Their antioxidant activity as the inhibition of thiobarbituric reactive substances (TBARS), total phenolic content(Folin-Ciocalteau)and phenolic fingerprint (HPLC-UV-DAD)were also evaluated.Results: Berberis vulgaris, Jasonia glutinosa, Satureja montana andSideritis hirsuta ethanol extracts were potent inhibitors of cytokine production but did not exert significant effects on prostaglandins synthesis. This effect was even stronger when monocytes were incubated in the presence of both aqueous and ethanol extracts of Thymus vulgaris. Prunus spinosaethanol extract presents an overall strong pro-inflammatory effect instead. B.vulgaris, J.glutinosa, S.montana andT.vulgarisethanol extracts were the richest in phenols (c.a.2 mg/mL caffeic acid equivalents) but the antioxidant effect did not correlate with this parameter pointing towards the presence of potent antioxidants from other phytochemical classes.Conclusion: Overall, this project provides evidence of the efficacy attributed to severalspecies central to the medical folklore in Teruel (Spain). Their anti-inflammatory and antioxidant activity profile will support further phytochemical-pharmacological investigations
Neurogenic inflammation after traumatic brain injury and its potentiation of classical inflammation
Background: The neuroinflammatory response following traumatic brain injury (TBI) is known to be a key secondary injury factor that can drive ongoing neuronal injury. Despite this, treatments that have targeted aspects of the inflammatory pathway have not shown significant efficacy in clinical trials. Main body: We suggest that this may be because classical inflammation only represents part of the story, with activation of neurogenic inflammation potentially one of the key initiating inflammatory events following TBI. Indeed, evidence suggests that the transient receptor potential cation channels (TRP channels), TRPV1 and TRPA1, are polymodal receptors that are activated by a variety of stimuli associated with TBI, including mechanical shear stress, leading to the release of neuropeptides such as substance P (SP). SP augments many aspects of the classical inflammatory response via activation of microglia and astrocytes, degranulation of mast cells, and promoting leukocyte migration. Furthermore, SP may initiate the earliest changes seen in blood-brain barrier (BBB) permeability, namely the increased transcellular transport of plasma proteins via activation of caveolae. This is in line with reports that alterations in transcellular transport are seen first following TBI, prior to decreases in expression of tight-junction proteins such as claudin-5 and occludin. Indeed, the receptor for SP, the tachykinin NK1 receptor, is found in caveolae and its activation following TBI may allow influx of albumin and other plasma proteins which directly augment the inflammatory response by activating astrocytes and microglia. Conclusions: As such, the neurogenic inflammatory response can exacerbate classical inflammation via a positive feedback loop, with classical inflammatory mediators such as bradykinin and prostaglandins then further stimulating TRP receptors. Accordingly, complete inhibition of neuroinflammation following TBI may require the inhibition of both classical and neurogenic inflammatory pathways.Frances Corrigan, Kimberley A. Mander, Anna V. Leonard and Robert Vin
Anti-neuroinflammatory effects of GPR55 antagonists in LPS-activated primary microglial cells
Background: Neuroinflammation plays a vital role in Alzheimer’s disease and other neurodegenerative conditions. Microglia are the resident mononuclear immune cells of the central nervous system, and they play essential roles in the maintenance of homeostasis and responses to neuroinflammation. The orphan G-protein-coupled receptor 55 (GPR55) has been reported to modulate inflammation and is expressed in immune cells such as monocytes and microglia. However, its effects on neuroinflammation, mainly on the production of members of the arachidonic acid pathway in activated microglia, have not been elucidated in detail.
Methods: In this present study, a series of coumarin derivatives, that exhibit GPR55 antagonism properties, were designed. The effects of these compounds on members of the arachidonic acid cascade were studied in lipopolysaccharide (LPS)-treated primary rat microglia using Western blot, qPCR, and ELISA.
Results: We demonstrate here that the various compounds with GPR55 antagonistic activities significantly inhibited the release of PGE₂ in primary microglia. The inhibition of LPS-induced PGE₂ release by the most potent candidate KIT 17 was partially dependent on reduced protein synthesis of mPGES-1 and COX-2. KIT 17 did not affect any key enzyme involved on the endocannabinoid system. We furthermore show that microglia expressed GPR55 and that a synthetic antagonist of the GPR receptor (ML193) demonstrated the same effect of the KIT 17 on the inhibition of PGE₂.
Conclusions: Our results suggest that KIT 17 is acting as an inverse agonist on GPR55 independent of the endocannabinoid system. Targeting GPR55 might be a new therapeutic option to treat neurodegenerative diseases with a neuroinflammatory background such as Alzheimer’s disease, Parkinson, and multiple sclerosis (MS)
Current research in biotechnology: Exploring the biotech forefront
Biotechnology is an evolving research field that covers a broad range of topics. Here we aimed to evaluate the latest research literature, to identify prominent research themes, major contributors in terms of institutions, countries/regions, and journals. The Web of Science Core Collection online database was searched to retrieve biotechnology articles published since 2017. In total, 12,351 publications were identified and analyzed. Over 8500 institutions contributed to these biotechnology publications, with the top 5 most productive ones scattered over France, China, the United States of America, Spain, and Brazil. Over 140 countries/regions contributed to the biotechnology research literature, led by the United States of America, China, Germany, Brazil, and India. Journal of Bioscience and Bioengineering was the most productive journal in terms of number of publications. Metabolic engineering was among the most prevalent biotechnology study themes, and Escherichia coli and Saccharomyces cerevisiae were frequently used in biotechnology investigations, including the biosynthesis of useful biomolecules, such as myo-inositol (vitamin B8), monoterpenes, adipic acid, astaxanthin, and ethanol. Nanoparticles and nanotechnology were identified too as emerging biotechnology research themes of great significance. Biotechnology continues to evolve and will remain a major driver of societal innovation and development
Pharmacological inhibition of Akt and downstream pathways modulates the expression of COX-2 and mPGES-1 in activated microglia
<p>Abstract</p> <p>Background</p> <p>Microglia are considered a major target for modulating neuroinflammatory and neurodegenerative disease processes. Upon activation, microglia secrete inflammatory mediators that contribute to the resolution or to further enhancement of damage in the central nervous system (CNS). Therefore, it is important to study the intracellular pathways that are involved in the expression of the inflammatory mediators. Particularly, the role of the phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) and glycogen synthase kinase-3 (GSK-3) pathways in activated microglia is unclear. Thus, in the present study we investigated the role of Akt and its downstream pathways, GSK-3 and mTOR, in lipopolysaccharide (LPS)-activated primary rat microglia by pharmacological inhibition of these pathways in regard to the expression of cyclooxygenase (COX)-2 and microsomal prostaglandin E synthase-1 (mPGES-1) and to the production of prostaglandin (PG) E<sub>2 </sub>and PGD<sub>2</sub>.</p> <p>Findings</p> <p>We show that inhibition of Akt by the Akt inhibitor X enhanced the production of PGE<sub>2 </sub>and PGD<sub>2 </sub>without affecting the expression of COX-2, mPGES-1, mPGES-2 and cytosolic prostaglandin E synthase (cPGES). Moreover, inhibition of GSK-3 reduced the expression of both COX-2 and mPGES-1. In contrast, the mTOR inhibitor rapamycin enhanced both COX-2 and mPGES-1 immunoreactivity and the release of PGE<sub>2 </sub>and PGD<sub>2</sub>. Interestingly, NVP-BEZ235, a dual PI3K/mTOR inhibitor, enhanced COX-2 and reduced mPGES-1 immunoreactivity, albeit PGE<sub>2 </sub>and PGD<sub>2 </sub>levels were enhanced in LPS-stimulated microglia. However, this compound also increased PGE<sub>2 </sub>in non-stimulated microglia.</p> <p>Conclusion</p> <p>Taken together, we demonstrate that blockade of mTOR and/or PI3K/Akt enhances prostanoid production and that PI3K/Akt, GSK-3 and mTOR differently regulate the expression of mPGES-1 and COX-2 in activated primary microglia. Therefore, these pathways are potential targets for the development of novel strategies to modulate neuroinflammation.</p
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