Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Trends Biochem Sci ; 49(3): 189-191, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38160063

RESUMO

A recent report by Chen et al. describes the discovery of RmNMT, a highly active and promiscuous tryptamine N-methyltransferase from the cane toad, Rhinella marina. N,N-dimethyltryptamine derivatives produced by this enzyme were then evaluated for their potential to serve as next-generation treatments for mental health disorders.


Assuntos
Alucinógenos , Alucinógenos/farmacologia , N,N-Dimetiltriptamina
2.
J Med Chem ; 66(24): 16728-16761, 2023 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-38100045

RESUMO

E3 ubiquitin ligase, Constitutive Photomorphogenic 1 (COP1) regulates turnover of Adipose Triglyceride Lipase (ATGL), the rate-limiting lipolytic enzyme. Genetic perturbation in the COP1-ATGL axis disrupts lipid homeostasis, leading to liver steatosis. Using drug development strategies, we herein report quinazolinone and quinazolinedione based modulators for COP1-ATGL axis. Systematic SAR studies and subsequent optimization were performed by incorporating relevant functional groups at the N1, N3, C5, and C6 positions of both scaffolds. Compounds' efficacy was evaluated by multiple biological assays and ADME profiling. The lead compound 86 could increase ATGL protein expression, reduce ATGL ubiquitination and COP1 autoubiquitination, and diminish lipid accumulation in hepatocytes in the nanomolar range. Oral administration of 86 abrogated triglyceride accumulation and resolved fibrosis in preclinical Nonalcoholic Fatty Liver Disease (NAFLD) model. The study thus establishes quinazolinedione as a viable chemotype to therapeutically modulate the activity of COP1 and ATGL in relevant clinical contexts.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Quinazolinonas/farmacologia , Quinazolinonas/metabolismo , Lipase , Hepatócitos/metabolismo , Triglicerídeos/metabolismo
3.
Metab Eng ; 78: 61-71, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37230161

RESUMO

N,N-dimethyltryptamine (DMT), 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) and 5-hydroxy-N,N-dimethyltryptamine (bufotenine) are psychedelic tryptamines found naturally in both plants and animals and have shown clinical potential to help treat mental disorders, such as anxiety and depression. Advances in both metabolic and genetic engineering make it possible to engineer microbes as cell factories to produce DMT and its aforementioned derivatives to meet demand for ongoing clinical study. Here, we present the development of a biosynthetic production pathway for DMT, 5-MeO-DMT, and bufotenine in the model microbe Escherichia coli. Through the application of genetic optimization techniques and process optimization in benchtop fermenters, the in vivo production of DMT in E. coli was observed. DMT production with tryptophan supplementation reached maximum titers of 74.7 ± 10.5 mg/L under fed batch conditions in a 2-L bioreactor. Additionally, we show the first reported case of de novo production of DMT (from glucose) in E. coli at a maximum titer of 14.0 mg/L and report the first example of microbial 5-MeO-DMT and bufotenine production in vivo. This work provides a starting point for further genetic and fermentation optimization studies with the goal to increase methylated tryptamine production metrics to industrially competitive levels.


Assuntos
Bufotenina , Alucinógenos , Animais , Bufotenina/metabolismo , N,N-Dimetiltriptamina , Escherichia coli/genética , Escherichia coli/metabolismo , Metoxidimetiltriptaminas
4.
Behav Brain Res ; 440: 114262, 2023 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-36529299

RESUMO

Psilocybin and its active metabolite psilocin are hallucinogenic serotonergic agonists with high affinity for several serotonin receptors. In addition to underlying the hallucinogenic effects of these compounds, serotonin receptor activation also has important effects on decision-making and goal-directed behaviors. The impact of psilocybin and psilocin on these cognitive systems, however, remains unclear. This study investigated the effects of psilocybin treatment on decision-making and motivation in healthy male and female rats. We compared probability and delay discounting performance of psilocybin treated (1 mg/kg) to vehicle rats (n = 10/sex/group), and further assessed motivation in each group using a progressive ratio task. We also confirmed drug action by assessing head twitch responses after psilocybin treatment (1 mg/kg). Results from this study demonstrated that exposure to 1 mg/kg psilocybin did not affect decision-making in the probability and delay discounting tasks and did not reduce response rates in the progressive ratio task. However, psilocybin treatment did cause the expected increase in head twitch responses in both male and female rats, demonstrating that the drug was delivered at a pharmacologically relevant dosage. Combined, these results suggest that psilocybin may not impair or improve decision-making and motivation. Considering recent interest in psilocybin as a potential fast-acting therapeutic for a variety of mental health disorders, our findings also suggest the therapeutic effects of this drug may not be mediated by changes to the brain systems underlying reward and decision-making. Finally, these results may have important implications regarding the relative safety of this compound, suggesting that widespread cognitive impairments may not be seen in subjects, even after chronic treatment.


Assuntos
Alucinógenos , Psilocibina , Ratos , Masculino , Feminino , Animais , Psilocibina/farmacologia , Alucinógenos/farmacologia , Motivação , Encéfalo/metabolismo , Serotonina/farmacologia , Receptores de Serotonina/metabolismo
5.
Mol Ther ; 31(5): 1402-1417, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-36380587

RESUMO

Extracellular vesicles (EVs) are nanovesicles released by all eukaryotic cells. This work reports the first nanoscale fluorescent visualization of tumor-originating vesicles bearing an angiogenic microRNA (miR)-126 cargo. In a validated experimental model of lethal murine vascular neoplasm, tumor-originating EV delivered its miR-126 cargo to tumor-associated macrophages (TAMs). Such delivery resulted in an angiogenic (LYVE+) change of state in TAM that supported tumor formation. Study of the trafficking of tumor-originating fluorescently tagged EV revealed colocalization with TAM demonstrating uptake by these cells. Ex vivo treatment of macrophages with tumor-derived EVs led to gain of tumorigenicity in these isolated cells. Single-cell RNA sequencing of macrophages revealed that EV-borne miR-126 characterized the angiogenic change of state. Unique gene expression signatures of specific macrophage clusters responsive to miR-126-enriched tumor-derived EVs were revealed. Topical tissue nanotransfection (TNT) delivery of an oligonucleotide comprising an anti-miR against miR-126 resulted in significant knockdown of miR-126 in the tumor tissue. miR-126 knockdown resulted in complete involution of the tumor and improved survival rate of tumor-affected mice. This work identifies a novel tumorigenic mechanism that relies on tumorigenic state change of TAM caused by tumor-originating EV-borne angiomiR. This disease process can be effectively targeted by topical TNT of superficial tumors.


Assuntos
Vesículas Extracelulares , MicroRNAs , Animais , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Macrófagos/metabolismo , Fagocitose , Vesículas Extracelulares/metabolismo
6.
Heliyon ; 8(11): e11710, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36468141

RESUMO

In recent days, the utilization of lightweight alloys for various applications has been increased massively. Starting from the automobile industry, aerospace industry, and even in the biomedical field, there is a need for dissimilar precise joining of steel to other light alloys (magnesium alloy, aluminum alloy, titanium alloy). However, those alloys are characterized by different melting temperatures, machinability, strength, thermal conductivity, and oxygen reactivity. Considering this welding to challenge ongoing laser welding efforts to improve laser welding quality by altering the welding techniques, modes, proper use of shielding gasses, using suitable process parameters, and even proper joint and surface preparations are discussed. The feasibility of implementing all those things in the industrial setup can be understood only after analyzing recent works. Changes in microstructure and the defects (solidification cracking, intermetallic components formation, porosity) arrived during and after laser welding of these materials are reviewed. The paper also highlights the effect of shielding gas, welding speed, laser power, defocusing position, etc. during laser welding of lightweight materials. The critical issues related to dissimilar laser welding of these combinations and some remedial measures are discussed. The purpose of this review is to emphasize and understand the recent trends of dissimilar laser welding and explore the scope of industry level applications.

7.
Metab Eng Commun ; 14: e00196, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35310468

RESUMO

Interest in the potential therapeutic efficacy of psilocybin and other psychedelic compounds has escalated significantly in recent years. To date, little is known regarding the biological activity of the psilocybin pathway intermediate, norbaeocystin, due to limitations around sourcing the phosphorylated tryptamine metabolite for in vivo testing. To address this limitation, we first developed a novel E. coli platform for the rapid and scalable production of gram-scale amounts of norbaeocystin. Through this process we compare the genetic and fermentation optimization strategies to that of a similarly constructed and previously reported psilocybin producing strain, uncovering the need for reoptimization and balancing upon even minor genetic modifications to the production host. We then perform in vivo measurements of head twitch response to both biosynthesized psilocybin and norbaeocystin using both a cell broth and water vehicle in Long-Evans rats. The data show a dose response to psilocybin while norbaeocystin does not elicit any pharmacological response, suggesting that norbaeocystin and its metabolites may not have a strong affinity for the serotonin 2A receptor. The findings presented here provide a mechanism to source norbaeocystin for future studies to evaluate its disease efficacy in animal models, both individually and in combination with psilocybin, and support the safety of cell broth as a drug delivery vehicle.

8.
Sci Rep ; 11(1): 21723, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34741051

RESUMO

Coronavirus with intact infectivity attached to PPE surfaces pose significant threat to the spread of COVID-19. We tested the hypothesis that an electroceutical fabric, generating weak potential difference of 0.5 V, disrupts the infectivity of coronavirus upon contact by destabilizing the electrokinetic properties of the virion. Porcine respiratory coronavirus AR310 particles (105) were placed in direct contact with the fabric for 1 or 5 min. Following one minute of contact, zeta potential of the porcine coronavirus was significantly lowered indicating destabilization of its electrokinetic properties. Size-distribution plot showed appearance of aggregation of the virus. Testing of the cytopathic effects of the virus showed eradication of infectivity as quantitatively assessed by PI-calcein and MTT cell viability tests. This work provides the rationale to consider the studied electroceutical fabric, or other materials with comparable property, as material of choice for the development of PPE in the fight against COVID-19.


Assuntos
COVID-19/prevenção & controle , COVID-19/transmissão , Eletroquímica/métodos , Têxteis , Animais , Anti-Infecciosos , Líquidos Corporais , Linhagem Celular , Sobrevivência Celular , Fluoresceínas , Humanos , Peróxido de Hidrogênio , Cinética , Nanopartículas , Propídio , SARS-CoV-2 , Suínos , Temperatura , Sais de Tetrazólio , Tiazóis , Vírion , Cicatrização
9.
Antioxid Redox Signal ; 34(2): 137-153, 2021 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-32597200

RESUMO

Aims: Hemangioendothelioma (HE) may be benign or malignant. Mouse hemangioendothelioma endothelial (EOMA) cells are validated to study mechanisms in HE. This work demonstrates that EOMA cells heavily rely on mitochondria to thrive. Thus, a combination therapy, including weak X-ray therapy (XRT, 0.5 Gy) and a standardized natural berry extract (NBE) was tested. This NBE is known to be effective in managing experimental HE and has been awarded with the Food and Drug Administration Investigational New Drug (FDA-IND) number 140318 for clinical studies on infantile hemangioma. Results: NBE treatment alone selectively attenuated basal oxygen consumption rate of EOMA cells. NBE specifically sensitized EOMA, but not murine aortic endothelial cells to XRT-dependent attenuation of mitochondrial respiration and adenosine triphosphate (ATP) production. Combination treatment, selectively and potently, influenced mitochondrial dynamics in EOMA cells such that fission was augmented. This was achieved by lowering of mitochondrial sirtuin 3 (SIRT3) causing increased phosphorylation of AMP-activated protein kinase (AMPK). A key role of SIRT3 in loss of EOMA cell viability caused by the combination therapy was evident when pyrroloquinoline quinone, an inducer of SIRT3, pretreatment rescued these cells. Innovation and Conclusion: Mitochondria-targeting NBE significantly extended survival of HE-affected mice. The beneficial effect of NBE in combination with weak X-ray therapy was, however, far more potent with threefold increase in murine survival. The observation that safe natural products may target tumor cell mitochondria and sharply lower radiation dosage required for tumor management warrants clinical testing.


Assuntos
Hemangioendotelioma/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , Extratos Vegetais/farmacologia , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Feminino , Frutas/química , Hemangioendotelioma/metabolismo , Humanos , Camundongos , Mitocôndrias/metabolismo , Fosforilação/efeitos dos fármacos , Sirtuína 3/metabolismo
10.
Ther Adv Endocrinol Metab ; 10: 2042018819889024, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31832130

RESUMO

AIMS: Obesity associated prolonged hyperinsulinemia followed by ß-cell failure is well established as the pathology behind type 2 diabetes mellitus (T2DM). However, studies on nonobese T2DM have reported it to be a distinct clinical entity with predominant insulin secretory defect. We, therefore, hypothesized that compensatory hyperinsulinemia in response to weight gain is impaired in nonobese subjects. METHODS: This was a cross-sectional study from a community-based metabolic health screening program. Adiposity parameters including body mass index (BMI), waist circumference (WC), body fat percentage, plasma leptin concentration and metabolic parameters namely fasting insulin, glucose, total cholesterol, and triglycerides were measured in 650 individuals (73% healthy, 62% nonobese with a BMI <25). RESULTS: In contrast to obese T2DM, nonobese T2DM patients did not exhibit significant hyperinsulinemia compared with the nonobese healthy group. Age, sex, and fasting glucose adjusted insulin levels, homeostatic model assessment of insulin resistance (HOMA-IR) and HOMA-beta cell function (HOMA-B) were increased in obese T2DM compared with nonobese T2DM. Although adiposity parameters showed strong correlation with fasting insulin in obese healthy (r = 0.38, 0.38, and 0.42, respectively; all p values < 0.001) and T2DM (r = 0.54, 0.54, and 0.66, respectively; all p < 0.001), only BMI and leptin showed a weak correlation with insulin in the nonobese healthy group (0.13 and 0.13, respectively; all p < 0.05) which were completely lost in the nonobese T2DM. CONCLUSIONS: Compensatory hyperinsulinemia in response to weight gain is impaired in the nonobese population making insulin secretory defect rather than IR the major pathology behind nonobese T2DM.

11.
Environ Monit Assess ; 189(6): 262, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28488227

RESUMO

Identification of tree species that can biologically monitor air pollution and can endure air pollution is very much important for a sustainable green belt development around any polluted place. To ascertain the species, ten tree species were selected on the basis of some previous study from the campus of the University of Burdwan and were studied in the pre-monsoon and post-monsoon seasons. The study has been designed to investigate biochemical and physiological activities of selected tree species as the campus is presently exposed to primary air pollutants and their impacts on plant community were observed through the changes in several physical and biochemical constituents of plant leaves. As the plant species continuously exchange different gaseous pollutants in and out of the foliar system and are very sensitive to gaseous pollutants, they serve as bioindicators. Due to air pollution, foliar surface undergoes different structural and functional changes. In the selected plant species, it was observed that the concentration of primary air pollutants, proline content, pH, relative water holding capacity, photosynthetic rate, and respiration rate were higher in the pre-monsoon than the post-monsoon season, whereas the total chlorophyll, ascorbic acid, sugar, and conductivity were higher in the post-monsoon season. From the entire study, it was observed that the concentration of sulfur oxide (SO x ), nitrogen oxide (NO x ), and suspended particulate matter (SPM) all are reduced in the post-monsoon season than the pre-monsoon season. In the pre-monsoon season, SO x , NO x , and SPM do not have any significant correlation with biochemical as well as physiological parameters. SPM shows a negative relationship with chlorophyll 'a' (r = -0.288), chlorophyll 'b' (r = -0.267), and total chlorophyll (r = -0.238). Similarly, chlorophyll a, chlorophyll b, and the total chlorophyll show negative relations with SO x and NO x (p < 0.005) during the post-monsoon season. Proline shows a positive relationship with SO x in the pre-monsoon season whereas in the post-monsoon season proline content shows a positive relationship with both SO x and NO x . The present study facilitates to screen eight sensitive and two moderately tolerant tree species according to their air pollution tolerance index (APTI) values.


Assuntos
Adaptação Fisiológica , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Árvores/fisiologia , Poluição do Ar/estatística & dados numéricos , Clorofila/metabolismo , Clorofila A , Material Particulado/análise , Fotossíntese , Folhas de Planta/química , Plantas , Estações do Ano , Água/análise
12.
Med Image Comput Comput Assist Interv ; 14(Pt 2): 557-65, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21995073

RESUMO

We introduce a novel discrete optimization method for non-rigid image registration based on the random walker algorithm. We discretize the space of deformations and formulate registration using a Gaussian MRF where continuous labels correspond to the probability of a point having a certain discrete deformation. The interaction (regularization) term of the corresponding MRF energy is convex and image dependent, thus being able to accommodate different types of tissue elasticity. This formulation results in a fast algorithm that can easily accommodate a large number of displacement labels, has provable robustness to noise and a close to global solution. We experimentally demonstrate the validity of our formulation on synthetic and real medical data.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Reconhecimento Automatizado de Padrão/métodos , Abdome/patologia , Algoritmos , Encéfalo/patologia , Diagnóstico por Imagem/métodos , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Modelos Estatísticos , Distribuição Normal , Software , Tomografia Computadorizada por Raios X/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...