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1.
J Ethnopharmacol ; 267: 113477, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33098971

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional pharmacopeias have been developed by multiple cultures and evaluated for efficacy and safety through both historical/empirical iteration and more recently through controlled studies using Western scientific paradigms and an increasing emphasis on data science methodologies for network pharmacology. Traditional medicines represent likely sources of relatively inexpensive drugs for symptomatic management as well as potential libraries of new therapeutic approaches. Leveraging this potential requires hard evidence for efficacy that separates science from pseudoscience. MATERIALS AND METHODS: We performed a review of non-Western medical systems and developed case studies that illustrate the epistemological and practical translative barriers that hamper their transition to integration with Western approaches. We developed a new data analytics approach, in silico convergence analysis, to deconvolve modes of action, and potentially predict desirable components of TM-derived formulations based on computational consensus analysis across cultures and medical systems. RESULTS: Abstraction, simplification and altered dose and delivery modalities were identified as factors that influence actual and perceived efficacy once a medicine is moved from a non-Western to Western setting. Case studies on these factors highlighted issues with translation between non-Western and Western epistemologies, including those where epistemological and medicinal systems drive markets that can be epicenters for zoonoses such as the novel Coronavirus. The proposed novel data science approach demonstrated the ability to identify and predict desirable medicinal components for a test indication, pain. CONCLUSIONS: Relegation of traditional therapies to the relatively unregulated nutraceutical industry may lead healthcare providers and patients to underestimate the therapeutic potential of these medicines. We suggest three areas of emphasis for this field: First, vertical integration and embedding of traditional medicines into healthcare systems would subject them to appropriate regulation and evidence-based practice, as viable integrative implementation mode. Second, we offer a new Bradford-Hill-like framework for setting research priorities and evaluating efficacy, with the goal of rescuing potentially valuable therapies from the nutraceutical market and discrediting those that are pseudoscience. Third, data analytics pipelines offer new capacity to generate new types of TMS-inspired medicines that are rationally-designed based on integrated knowledge across cultures, and also provide an evaluative framework against which to test claims of fidelity and efficacy to TMS made for nutraceuticals.


Assuntos
Ciência de Dados , Prestação Integrada de Cuidados de Saúde/organização & administração , Prestação Integrada de Cuidados de Saúde/tendências , Medicina Tradicional/tendências , COVID-19/terapia , Interpretação Estatística de Dados , Humanos , Medicina , Fitoterapia
2.
Channels (Austin) ; 13(1): 344-366, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31446830

RESUMO

Nociceptive Transient Receptor Potential channels such as TRPV1 are targets for treating pain. Both antagonism and agonism of TRP channels can promote analgesia, through inactivation and chronic desensitization. Since plant-derived mixtures of cannabinoids and the Cannabis component myrcene have been suggested as pain therapeutics, we screened terpenes found in Cannabis for activity at TRPV1. We used inducible expression of TRPV1 to examine TRPV1-dependency of terpene-induced calcium flux responses. Terpenes contribute differentially to calcium fluxes via TRPV1 induced by Cannabis-mimetic cannabinoid/terpenoid mixtures. Myrcene dominates the TRPV1-mediated calcium responses seen with terpenoid mixtures. Myrcene-induced calcium influx is inhibited by the TRPV1 inhibitor capsazepine and Myrcene elicits TRPV1 currents in the whole-cell patch-clamp configuration. TRPV1 currents are highly sensitive to internal calcium. When Myrcene currents are evoked, they are distinct from capsaicin responses on the basis of Imax and their lack of shift to a pore-dilated state. Myrcene pre-application and residency at TRPV1 appears to negatively impact subsequent responses to TRPV1 ligands such as Cannabidiol, indicating allosteric modulation and possible competition by Myrcene. Molecular docking studies suggest a non-covalent interaction site for Myrcene in TRPV1 and identifies key residues that form partially overlapping Myrcene and Cannabidiol binding sites. We identify several non-Cannabis plant-derived sources of Myrcene and other compounds targeting nociceptive TRPs using a data mining approach focused on analgesics suggested by non-Western Traditional Medical Systems. These data establish TRPV1 as a target of Myrcene and suggest the therapeutic potential of analgesic formulations containing Myrcene.


Assuntos
Monoterpenos Acíclicos/metabolismo , Alcenos/metabolismo , Canabinoides/metabolismo , Extratos Vegetais/metabolismo , Canal de Cátion TRPA1/metabolismo , Monoterpenos Acíclicos/química , Alcenos/química , Cálcio/metabolismo , Canabinoides/química , Cannabis/química , Linhagem Celular , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular , Extratos Vegetais/química , Canal de Cátion TRPA1/química , Terpenos/química , Terpenos/metabolismo
3.
Channels (Austin) ; 13(1): 264-286, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31237176

RESUMO

Calcium entry is central to the functional processes in mast cells and basophils that contribute to the induction and maintenance of inflammatory responses. Mast cells and basophils express an array of calcium channels, which mediate responses to diverse stimuli triggered by small bioactive molecules, physicochemical stimuli and immunological inputs including antigens and direct immune cell interactions. These cells are also highly responsive to certain venoms (such as Hymenoptera envenomations), which cause histamine secretion, cytokine release and an array of pro-inflammatory functional responses. There are gaps in our understanding of the coupling of venom exposure to specific signaling pathways such as activation of calcium channels. In the present study, we performed a current survey of a model mast cell line selected for its pleiotropic responsiveness to multiple pro-inflammatory inputs. As a heterogenous stimulus, Hymenoptera venom activates multiple classes of conductance at the population level but tend to lead to the measurement of only one type of conductance per cell, despite the cell co-expressing multiple channel types. The data show that ICRAC, IARC, and TRPV-like currents are present in the model mast cell populations and respond to venom exposure. We further assessed individual venom components, specifically secretagogues and arachidonic acid, and identified the conductances associated with these stimuli in mast cells. Single-cell calcium assays and immunofluorescence analysis show that there is heterogeneity of channel expression across the cell population, but this heterogeneity does not explain the apparent selectivity for specific channels in response to exposure to venom as a composite stimulus.


Assuntos
Venenos de Artrópodes/farmacologia , Mordeduras e Picadas/imunologia , Himenópteros/fisiologia , Mastócitos/imunologia , Animais , Venenos de Artrópodes/imunologia , Venenos de Artrópodes/toxicidade , Histamina/imunologia , Humanos , Himenópteros/imunologia , Mastócitos/efeitos dos fármacos , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/imunologia
4.
Channels (Austin) ; 13(1): 172-191, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31096838

RESUMO

Cannabinoid compounds are potential analgesics. Users of medicinal Cannabis report efficacy for pain control, clinical studies show that cannabis can be effective and opioid sparing in chronic pain, and some constituent cannabinoids have been shown to target nociceptive ion channels. Here, we explore and compare a suite of cannabinoids for their impact upon the physiology of TRPV1. The cannabinoids tested evoke differential responses in terms of kinetics of activation and inactivation. Cannabinoid activation of TRPV1 displays significant dependence on internal and external calcium levels. Cannabinoid activation of TRPV1 does not appear to induce the highly permeant, pore-dilated channel state seen with Capsaicin, even at high current amplitudes. Finally, we analyzed cannabinoid responses at nociceptive channels other than TRPV1 (TRPV2, TRPM8, and TRPA1), and report that cannabinoids differentially activate these channels. On the basis of response activation and kinetics, state-selectivity and receptor selectivity, it may be possible to rationally design approaches to pain using single or multiple cannabinoids.


Assuntos
Canabinoides/metabolismo , Canais de Cátion TRPV/metabolismo , Cálcio/metabolismo , Canabinoides/química , Células HEK293 , Humanos , Cinética , Canal de Cátion TRPA1/química , Canal de Cátion TRPA1/genética , Canal de Cátion TRPA1/metabolismo , Canais de Cátion TRPM/química , Canais de Cátion TRPM/genética , Canais de Cátion TRPM/metabolismo , Canais de Cátion TRPV/química , Canais de Cátion TRPV/genética
5.
J Extracell Vesicles ; 8(1): 1578589, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30815238

RESUMO

Large membrane derangements in the form of non-detaching blebs or membrane protrusions occur in a variety of cell stress and physiological situations and do not always reflect apoptotic processes. They have been studied in model mast cells under conditions of cell stress, but their potential physiological relevance to mast cell function and formation in primary mast cells or basophils have not been addressed. In the current study, we examine the large, non-detaching, non-apoptotic, membrane structures that form in model and primary mast cells under conditions of stimulation that are relevant to allergy, atopy and Type IV delayed hypersensitivity reactions. We characterized the inflation kinetics, dependency of formation upon external free calcium and striking geometric consistency of formation for large plasma membrane blebs (LPMBs). We describe that immunologically stimulated LPMBs in mast cells are constrained to form in locations where dissociation of the membrane-associated cytoskeleton occurs. Mast cell LPMBs decorate with wheat germ agglutinin, suggesting that they contain plasma membrane (PM) lectins. Electrophysiological capacitance measurements support a model where LPMBs are not being formed from internal membranes newly fused into the PM, but rather arise from stretching of the existing membrane, or inflation and smoothing of a micro-ruffled PM. This study provides new insights into the physiological manifestations of LPMB in response to immunologically relevant stimuli and in the absence of cell stress, death or apoptotic pathways.

6.
Phytother Res ; 29(4): 582-90, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25640812

RESUMO

Kava is a soporific, anxiolytic and relaxant in widespread ritual and recreational use throughout the Pacific. Traditional uses of kava by indigenous Pacific Island peoples reflect a complex pharmacopeia, centered on GABA-ergic effects of the well-characterized kavalactones. However, peripheral effects of kava suggest active components other than the CNS-targeted kavalactones. We have previously shown that immunocytes exhibit calcium mobilization in response to traditionally prepared kava extracts, and that the kavalactones do not induce these calcium responses. Here, we characterize the complex calcium-mobilizing activity of traditionally prepared and partially HPLC-purified kava extracts, noting induction of both calcium entry and store release pathways. Kava components activate intracellular store depletion of thapsigargin-sensitive and -insensitive stores that are coupled to the calcium release activated (CRAC) current, and cause calcium entry through non-store-operated pathways. Together with the pepper-like potency reported by kava users, these studies lead us to hypothesize that kava extracts contain one or more ligands for the transient receptor potential (TRP) family of ion channels. Indeed, TRP-like conductances are observed in kava-treated cells under patch clamp. Thus TRP-mediated cellular effects may be responsible for some of the reported pharmacology of kava.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Kava/química , Extratos Vegetais/farmacologia , Canais de Potencial de Receptor Transitório/metabolismo , Animais , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Ligantes , Técnicas de Patch-Clamp , Ratos , Tapsigargina/química
7.
Nature ; 411(6837): 590-5, 2001 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-11385574

RESUMO

The molecular mechanisms that regulate basal or background entry of divalent cations into mammalian cells are poorly understood. Here we describe the cloning and functional characterization of a Ca2+- and Mg2+-permeable divalent cation channel, LTRPC7 (nomenclature compatible with that proposed in ref. 1), a new member of the LTRPC family of putative ion channels. Targeted deletion of LTRPC7 in DT-40 B cells was lethal, indicating that LTRPC7 has a fundamental and nonredundant role in cellular physiology. Electrophysiological analysis of HEK-293 cells overexpressing recombinant LTRPC7 showed large currents regulated by millimolar levels of intracellular Mg.ATP and Mg.GTP with the permeation properties of a voltage-independent divalent cation influx pathway. Analysis of several cultured cell types demonstrated small magnesium-nucleotide-regulated metal ion currents (MagNuM) with regulation and permeation properties essentially identical to the large currents observed in cells expressing recombinant LTRPC7. Our data indicate that LTRPC7, by virtue of its sensitivity to physiological Mg.ATP levels, may be involved in a fundamental process that adjusts plasma membrane divalent cation fluxes according to the metabolic state of the cell.


Assuntos
Canais Iônicos/fisiologia , Proteínas de Membrana , Proteínas Quinases/fisiologia , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular , Galinhas , Clonagem Molecular , Marcação de Genes , Humanos , Canais Iônicos/genética , Camundongos , Dados de Sequência Molecular , Fosforilação , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases , Canais de Cátion TRPM
8.
Nature ; 411(6837): 595-9, 2001 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-11385575

RESUMO

Free ADP-ribose (ADPR), a product of NAD hydrolysis and a breakdown product of the calcium-release second messenger cyclic ADPR (cADPR), has no defined role as an intracellular signalling molecule in vertebrate systems. Here we show that a 350-amino-acid protein (designated NUDT9) and a homologous domain (NUDT9 homology domain) near the carboxy terminus of the LTRPC2/TrpC7 putative cation channel both function as specific ADPR pyrophosphatases. Whole-cell and single-channel analysis of HEK-293 cells expressing LTRPC2 show that LTRPC2 functions as a calcium-permeable cation channel that is specifically gated by free ADPR. The expression of native LTRPC2 transcripts is detectable in many tissues including the U937 monocyte cell line, in which ADPR induces large cation currents (designated IADPR) that closely match those mediated by recombinant LTRPC2. These results indicate that intracellular ADPR regulates calcium entry into cells that express LTRPC2.


Assuntos
Adenosina Difosfato Ribose/metabolismo , Canais de Cálcio/metabolismo , Ativação do Canal Iônico , Canais Iônicos/metabolismo , Proteínas de Membrana , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Cálcio/metabolismo , Canais de Cálcio/química , Canais de Cálcio/genética , Linhagem Celular , Clonagem Molecular , Escherichia coli , Humanos , Canais Iônicos/química , Canais Iônicos/genética , Dados de Sequência Molecular , Pirofosfatases/química , Pirofosfatases/genética , Pirofosfatases/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Sódio/metabolismo , Canais de Cátion TRPC , Canais de Cátion TRPM , Células U937
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