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1.
Neuromolecular Med ; 23(1): 25-46, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33547562

RESUMO

Neuro-inflammation accompanies numerous neurological disorders and conditions where it can be associated with a progressive neurodegenerative pathology. In a similar manner, alterations in sphingolipid metabolism often accompany or are causative features in degenerative neurological conditions. These include dementias, motor disorders, autoimmune conditions, inherited metabolic disorders, viral infection, traumatic brain and spinal cord injury, psychiatric conditions, and more. Sphingolipids are major regulators of cellular fate and function in addition to being important structural components of membranes. Their metabolism and signaling pathways can also be regulated by inflammatory mediators. Therefore, as certain sphingolipids exert distinct and opposing cellular roles, alterations in their metabolism can have major consequences. Recently, regulation of bioactive sphingolipids by neuro-inflammatory mediators has been shown to activate a neuronal NADPH oxidase 2 (NOX2) that can provoke damaging oxidation. Therefore, the sphingolipid-regulated neuronal NOX2 serves as a mechanistic link between neuro-inflammation and neurodegeneration. Moreover, therapeutics directed at sphingolipid metabolism or the sphingolipid-regulated NOX2 have the potential to alleviate neurodegeneration arising out of neuro-inflammation.


Assuntos
NADPH Oxidase 2/metabolismo , Doenças Neurodegenerativas/metabolismo , Esfingolipídeos/fisiologia , Complexo AIDS Demência/metabolismo , Animais , Produtos Biológicos/uso terapêutico , Encefalopatias Metabólicas Congênitas/genética , Encefalopatias Metabólicas Congênitas/metabolismo , Encefalopatias Metabólicas Congênitas/terapia , Descoberta de Drogas , Encefalite Viral/metabolismo , Ativação Enzimática , Terapia de Reposição de Enzimas , Humanos , Inflamação , Naftalenos/uso terapêutico , Proteínas do Tecido Nervoso/metabolismo , Doenças Neurodegenerativas/terapia , Neurônios/metabolismo , Oxirredução , Pirimidinonas/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Infecção por Zika virus/metabolismo
2.
Int J Biopharm Sci ; 2(1)2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33778816

RESUMO

Cancer is caused by a compilation of hereditary and environmental factors. In the past decade, next-generation sequencing has revealed the extent to which the microbiome influences the maintenance of homeostasis and therefore the prevention of diseases such as cancer. Current research efforts explore the interaction between cancer and the microbiome, and the results are anticipated to transform how clinicians approach cancer treatment. There is a plausible transition from the use of human genetic biomarkers to microbiomic biomarkers for genomic diagnostics. Considering the expanding knowledge of the ways in which the microbiome can affect the development of cancer, clinicians treating cancer patients should be considerate of how the microbiome can influence the host-drug or microbiome-cancer interactions. Recognition of the importance of the microbiome within the field of oncology is pertinent to understanding and furthering cancer development and treatment.

3.
Geroscience ; 40(2): 151-162, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29717416

RESUMO

Medicinal berries are appreciated for their health benefits, in traditional ecological knowledge and nutrition science. Determining the cellular mechanisms underlying the effects of berry supplementation may contribute to our understanding of aging. Here, we report that lowbush cranberry (Vaccinium vitis-idaea) treatment causes marked nuclear localization of the central aging-related transcription factor DAF-16/FOXO in aged Caenorhabditis elegans. Further, functional DAF-16 is required for the lifespan extension, improved mechanosensation, and posterior touch receptor neuron morphological changes induced by lowbush cranberry treatments. DAF-16 is not observed in nuceli nor required for lifespan extension in lifespan-extending Alaskan blueberry treatments and, while DAF-16 is not visibly induced into the nucleus in lifespan-extending Alaskan chaga treatments, it is required for chaga-induced lifespan extension. These findings underscore the importance of DAF-16 in the aging of whole organisms and touch receptor neurons and also, importantly, indicate that this critical pathway is not always activated upon consumption of functional foods that impact aging.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Extratos Vegetais/farmacologia , Vaccinium macrocarpon , Envelhecimento/genética , Animais , Antioxidantes/farmacologia , Axônios/metabolismo , Caenorhabditis elegans/genética , Longevidade/genética , Neurogênese/efeitos dos fármacos , Neurônios/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
4.
Int J Biopharm Sci ; 1(1)2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29607443

RESUMO

Acute myeloid leukemia (AML) is an aggressive hematological malignancy with high incidence in the aging population. In addition, AML is one of the more common pediatric malignancies. Unfortunately, both of these patient groups are quite sensitive to chemotherapy toxicities. Investigation of blueberries specifically as an anti-AML agent has been limited, despite being a prominent natural product with no reported toxicity. In this study, blueberry extracts are reported for the first time to exert a dietary therapeutic effect in animal models of AML. Furthermore, in vitro studies revealed that blueberry extracts exerted anti-AML efficacy against myeloid leukemia cell lines as well as against primary AML, and specifically provoked Erk and Akt regulation within the leukemia stem cell subpopulation. This study provides evidence that blueberries may be unique sources for anti-AML biopharmaceutical compound discovery, further warranting fractionation of this natural product. More so, blueberries themselves may provide an intriguing dietary option to enhance the anti-AML efficacy of traditional therapy for subsets of patients that otherwise may not tolerate rigorous combinations of therapeutics.

5.
Phytother Res ; 32(8): 1636-1641, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29701283

RESUMO

Acute myeloid leukemia (AML) is an aggressive hematological malignancy that is one of the more common pediatric malignancies in addition to occurring with high incidence in the aging population. Unfortunately, these patient groups are quite sensitive to toxicity from chemotherapy. Northern Labrador tea, or Rhododendron tomentosum Harmaja (a.k.a. Ledum palustre subsp. decumbens) or "tundra tea," is a noteworthy medicinal plant used by indigenous peoples in Alaska, Canada, and Greenland to treat a diversity of ailments. However, laboratory investigations of Northern Labrador tea, and other Labrador tea family members, as botanical sources for anticancer compounds have been limited. Utilizing an AML cell line in both in vitro and in vivo studies, as well as in vitro studies using primary human AML patient samples, this study demonstrated for the first time that Northern Labrador tea extracts can exert anti-AML activity and that this may be attributed to ursolic acid as a constituent component. Therefore, this medicinal herb holds the potential to serve as a source for further drug discovery efforts to isolate novel anti-AML compounds.


Assuntos
Ledum/química , Leucemia Mieloide Aguda/tratamento farmacológico , Extratos Vegetais/farmacologia , Triterpenos/farmacologia , Animais , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Plantas Medicinais/química , Ácido Ursólico
6.
Artigo em Inglês | MEDLINE | ID: mdl-30701264

RESUMO

Acute myeloid leukemia (AML) is an aggressive hematological malignancy with limited treatment options. Inflammation is often a contributing factor to the development and progression of AML, and related diseases, and can potentiate therapy failure. Previously, we had identified anti-inflammatory roles and anti-AML efficacy for blueberry extracts. The present study extended these observations to determine that the polyphenol quercetin inhibited neutral sphingomyelinase (N-SMase) activity and exerted anti-AML efficacy. Moreover, quercetin was shown to exert combinatorial anti-AML efficacy with nanoliposomal ceramide. Overall, this demonstrated that quercetin could block the pro-inflammatory actions of N-SMase and augment the efficacy of anti-AML therapeutics, including ceramide-based therapeutics.

8.
Front Aging Neurosci ; 8: 173, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27486399

RESUMO

Many nutritional interventions that increase lifespan are also proposed to postpone age-related declines in motor and cognitive function. Potential sources of anti-aging compounds are the plants and fungi that have adapted to extreme environments. We studied the effects of four commonly consumed and culturally relevant Interior Alaska berry and fungus species (bog blueberry, lowbush cranberry, crowberry, and chaga) on the decline in overall health and neuron function and changes in touch receptor neuron morphology associated with aging. We observed increased wild-type Caenorhabditis elegans lifespan and improved markers of healthspan upon treatment with Alaskan blueberry, lowbush cranberry, and chaga extracts. Interestingly, although all three treatments increased lifespan, they differentially affected the development of aberrant morphologies in touch receptor neurons. Blueberry treatments decreased anterior mechanosensory neuron (ALM) aberrations (i.e., extended outgrowths and abnormal cell bodies) while lowbush cranberry treatment increased posterior mechanosensory neuron (PLM) aberrations, namely process branching. Chaga treatment both decreased ALM aberrations (i.e., extended outgrowths) and increased PLM aberrations (i.e., process branching and loops). These results support the large body of knowledge positing that there are multiple cellular strategies and mechanisms for promoting health with age. Importantly, these results also demonstrate that although an accumulation of abnormal neuron morphologies is associated with aging and decreased health, not all of these morphologies are detrimental to neuronal and organismal health.

9.
Phytother Res ; 28(9): 1308-14, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25340187

RESUMO

Acute myeloid leukemia (AML) is a group of hematological malignancies defined by expanded clonal populations of immature progenitors (blasts) of myeloid phenotype in blood and bone marrow. Given a typical poor prognostic outlook, there is great need for novel agents with anti-AML activity. Devil's club (Oplopanax horridus) is one of the most significant medicinal plants used among the indigenous people of Southeast Alaska and the coastal Pacific Northwest, with different linguistic groups utilizing various parts of the plant to treat many different conditions including cancer. Studies identifying medically relevant components in Devil's club are limited. For this research study, samples were extracted in 70% ethanol before in vitro analysis, to assess effects on AML cell line viability as well as to study regulation of tyrosine phosphorylation and cysteine oxidation. The root extract displayed better in vitro anti-AML efficacy in addition to a noted anti-tyrosine kinase activity independent of an antioxidant effect. In vivo therapeutic studies using an immunocompetent murine model of AML further demonstrated that Devil's club root extract improved the murine survival while decreasing immunosuppressive regulatory T cells and improving CD8+ T-cell functionality. This study defines for the first time an anti-AML efficacy for extracts of Devil's club.


Assuntos
Leucemia Mieloide Aguda/tratamento farmacológico , Oplopanax/química , Extratos Vegetais/farmacologia , Animais , Linfócitos T CD8-Positivos/citologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fitoterapia , Plantas Medicinais/química , Transdução de Sinais , Linfócitos T Reguladores/citologia
10.
Oxid Med Cell Longev ; 2012: 768101, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22530077

RESUMO

Inflammation and oxidative stress are key to the progressive neuronal degeneration common to chronic pathologies, traumatic injuries, and aging processes in the CNS. The proinflammatory cytokine tumor necrosis factor-alpha (TNF-α) orchestrates cellular stress by stimulating the production and release of neurotoxic mediators including reactive oxygen species (ROS). NADPH oxidases (NOX), ubiquitously expressed in all cells, have recently emerged as pivotal ROS sources in aging and disease. We demonstrated the presence of potent NOX inhibitors in wild Alaska bog blueberries partitioning discretely into a nonpolar fraction with minimal antioxidant capacity and largely devoid of polyphenols. Incubation of SH-SY5Y human neuroblastoma cells with nonpolar blueberry fractions obstructed the coalescing of lipid rafts into large domains disrupting NOX assembly therein and abolishing ROS production characteristic for TNF-α exposure. These findings illuminate nutrition-derived lipid raft modulation as a novel therapeutic approach to blunt inflammatory and oxidative stress in the aging or diseased CNS.


Assuntos
Mirtilos Azuis (Planta)/química , NADPH Oxidases/metabolismo , Neurônios/efeitos dos fármacos , Extratos Vegetais/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Linhagem Celular Tumoral , Humanos , Neurônios/citologia , Neurônios/enzimologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Espécies Reativas de Oxigênio/metabolismo
11.
Analyst ; 133(3): 339-47, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18299748

RESUMO

A low-field medium-resolution NMR spectrometer, with an operating frequency of 29 MHz for 1H, has been assessed for on-line process analysis. A flow cell that incorporates a pre-magnetisation region has been developed to minimise the decrease in the signal owing to incomplete polarisation effects. The homogeneous esterification reaction of crotonic acid and 2-butanol was monitored using a simple sampling loop; it was possible to monitor the progression of the reaction through changes in CH signal areas of butanol and butyl crotonate. On-line analysis of heterogeneous water-toluene mixtures proved more challenging and a fast sampling loop system was devised for use with a 5 L reactor. The fast sampling loop operated at a flow rate of 8 L min(-1) and a secondary sampling loop was used to pass a sub-sample through the NMR analyser at a slower (mL min(-1)) rate. It was shown that even with super-isokinetic sampling conditions, unrepresentative sampling could occur owing to inadequate mixing in the reactor. However, it was still possible to relate the 1H NMR signal obtained at a flow rate of 60 mL min(-1) to the composition of the reactor contents.

12.
Analyst ; 128(12): 1467-70, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14737234

RESUMO

A miniaturised mid-infrared (MIR) spectrometer attached directly to an in-line immersion probe with an attenuated total reflectance crystal has been used to monitor the progression of the batch reaction of crotonic acid and 2-butanol in toluene. Univariate calibration, using the signal at 1188 cm(-1) in the 2nd derivative spectrum, gave accurate (average error, 1.6%) and precise (average relative standard deviation, 5.2%) estimation of 2-butyl crotonate concentrations in the range 0.08-0.49 mol dm(-3). Calibration by partial least squares was of no additional benefit in this application. The performance of in-line MIR spectrometry was comparable to that of an off-line reference gas chromatography method and superior to that of other in-line process analysis techniques (near-infrared, Raman or UV-visible spectrometries).

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