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1.
Transl Stroke Res ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488999

RESUMO

Clinical studies have identified widespread white matter degeneration in ischemic stroke patients. However, contemporary research in stroke has predominately focused on the infarct and periinfarct penumbra regions. The involvement of white matter degeneration after ischemic stroke and its contribution to post-stroke cognitive impairment and dementia (PSCID) has remained less explored in experimental models. In this study, we examined the progression of locomotor and cognitive function up to 4 months after inducing ischemic stroke by middle cerebral artery occlusion in young adult rats. Despite evident ongoing locomotor recovery, long-term cognitive and affective impairments persisted after ischemic stroke, as indicated by Morris water maze, elevated plus maze, and open field performance. At 4 months after stroke, multimodal MRI was conducted to assess white matter degeneration. T2-weighted MRI (T2WI) unveiled bilateral cerebroventricular enlargement after ischemic stroke. Fluid Attenuated Inversion Recovery MRI (FLAIR) revealed white matter hyperintensities in the corpus callosum and fornix across bilateral hemispheres. A positive association between the volume of white matter hyperintensities and total cerebroventricular volume was noted in stroke rats. Further evidence of bilateral white matter degeneration was indicated by the reduction of fractional anisotropy and quantitative anisotropy at bilateral corpus callosum in diffusion-weighted MRI (DWI) analysis. Additionally, microglia and astrocyte activation were identified in the bilateral corpus callosum after stroke. Our study suggests that experimental ischemic stroke induced by MCAO in young rat replicate long-term cognitive impairment and bihemispheric white matter degeneration observed in ischemic stroke patients. This model provides an invaluable tool for unraveling the mechanisms underlying post-stroke secondary white matter degeneration and its contribution to PSCID.

2.
Aging Dis ; 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38377020

RESUMO

Glutamate-mediated excitotoxicity has been extensively explored as a therapeutic target for the development of potential treatments of neurological disorders including stroke. However, the effect of glutamate on astrocytes under pathological conditions has been less studied. Using primary astrocyte culture, we determined the effect of glutamate on astrocytes against ischemic insult. Glutamate provided a cytoprotective effect and acted as an alternative substrate for ATP production in primary astrocytes against oxygen glucose deprivation reoxygenation insult, which was blocked by glutamate uptake inhibition. The cytoprotective effect of glutamate appears to be astrocyte-specific, as glutamate dose-dependently induces cytotoxic action in murine hippocampal HT-22 cell line. Interestingly, the cytoprotective effect of glutamate against glucose deprivation was short-last, as no protection was observed after 3-day glucose deprivation. We determined the metabolic phenotype of primary astrocyte cultured in glucose or glutamate. Primary astrocytes cultured in glutamate displayed a different metabolic phenotype when compared to those cultured in glucose, evidenced by higher basal and maximal oxygen consumption rate (OCR), higher ATP production and proton leak-coupled OCR, as well as lower glycolysis. Furthermore, glutamate exposure resulted in astrocyte activation, evidenced by an increase in astrocyte size and GFAP expression. Our study demonstrated that glutamate exerts a dual effect on astrocytes under ischemic condition. Glutamate provides an alternative substrate for energy metabolism in the absence of glucose, thereby protecting astrocytes against ischemic insults. On the other hand, glutamate exposure induces astrogliosis. Modulation of glutamate uptake and metabolism in astrocytes may provide novel targets for alleviating ischemic injury and improving function recovery after ischemic stroke.

3.
ACS Omega ; 8(11): 10411-10418, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36969464

RESUMO

Controlling the isomeric impurity in a key raw material is always critical to achieve the corresponding pure isomer-free targeted active pharmaceutical ingredient (API) in downstream processing. Clarithromycin 9-(E)-oxime is the key raw material for the synthesis of the 9a-lactam macrolide, which is an interesting scaffold for the synthesis of several bioactive macrolides. Here demonstrated is a scalable process for the preparation of substantially pure clarithromycin 9-(E)-oxime, with less than 1.2% of the (Z)-isomer. The process does not involve a separate time-consuming purification by a crystallization operation to purge the undesired (Z)-oxime isomer. Further, the pure clarithromycin 9-(E)-oxime obtained was subjected to the Beckmann rearrangement, thereby converting it into the pure 9a-lactam scaffold. Additionally, a few other impurities were identified and controlled at each stage. The fine-tuned process was successfully up scaled to a multikilogram scale, enabling the large-scale manufacturing of potential APIs derived from this scaffold.

4.
Life (Basel) ; 13(1)2023 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-36676133

RESUMO

Astrocytes play critical roles in regulating neuronal synaptogenesis, maintaining blood-brain barrier integrity, and recycling neurotransmitters. Increasing numbers of studies have suggested astrocyte heterogeneity in morphology, gene profile, and function. However, metabolic phenotype of astrocytes in different brain regions have not been explored. In this paper, we investigated the metabolic signature of cortical and cerebellar astrocytes using primary astrocyte cultures. We observed that cortical astrocytes were larger than cerebellar astrocytes, whereas cerebellar astrocytes had more and longer processes than cortical astrocytes. Using a Seahorse extracellular flux analyzer, we demonstrated that cortical astrocytes had higher mitochondrial respiration and glycolysis than cerebellar astrocytes. Cerebellar astrocytes have lower spare capacity of mitochondrial respiration and glycolysis as compared with cortical astrocytes. Consistently, cortical astrocytes have higher mitochondrial oxidation and glycolysis-derived ATP content than cerebellar astrocytes. In addition, cerebellar astrocytes have a fuel preference for glutamine and fatty acid, whereas cortical astrocytes were more dependent on glucose to meet energy demands. Our study indicated that cortical and cerebellar astrocytes display distinct metabolic phenotypes. Future studies on astrocyte metabolic heterogeneity and brain function in aging and neurodegeneration may lead to better understanding of the role of astrocyte in brain aging and neurodegenerative disorders.

5.
Transl Stroke Res ; 14(5): 740-751, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-35867329

RESUMO

Transient ischemic attack (TIA) presents a high risk for subsequent stroke, Alzheimer's disease (AD), and related dementia (ADRD). However, the neuropathophysiology of TIA has been rarely studied. By evaluating recurrent TIA-induced neuropathological changes, our study aimed to explore the potential mechanisms underlying the contribution of TIA to ADRD. In the current study, we established a recurrent TIA model by three times 10-min middle cerebral artery occlusion within a week in rat. Neither permanent neurological deficit nor apoptosis was observed following recurrent TIA. No increase of AD-related biomarkers was indicated after TIA, including increase of tau hyperphosphorylation and ß-site APP cleaving enzyme 1 (BACE1). Neuronal cytoskeleton modification and neuroinflammation was found at 1, 3, and 7 days after recurrent TIA, evidenced by the reduction of microtubule-associated protein 2 (MAP2), elevation of neurofilament-light chain (NFL), and increase of glial fibrillary acidic protein (GFAP)-positive astrocytes and ionized calcium binding adaptor molecule 1 (Iba1)-positive microglia at the TIA-affected cerebral cortex and basal ganglion. Similar NFL, GFAP and Iba1 alteration was found in the white matter of corpus callosum. In summary, the current study demonstrated that recurrent TIA may trigger neuronal cytoskeleton change, astrogliosis, and microgliosis without induction of cell death at the acute and subacute stage. Our study indicates that TIA-induced neuronal cytoskeleton modification and neuroinflammation may be involved in the vascular contribution to cognitive impairment and dementia.


Assuntos
Doença de Alzheimer , Ataque Isquêmico Transitório , Ratos , Animais , Ataque Isquêmico Transitório/metabolismo , Gliose/etiologia , Secretases da Proteína Precursora do Amiloide , Doenças Neuroinflamatórias , Ácido Aspártico Endopeptidases , Citoesqueleto/metabolismo , Modelos Teóricos
6.
Proc Natl Acad Sci U S A ; 119(14): e2122217119, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35344434

RESUMO

SignificanceA clear mechanistic understanding of metformin's antidiabetic effects is lacking. This is because suprapharmacological concentrations of metformin have been used in most studies. Using mouse models and human primary hepatocytes, we show that metformin, at clinically relevant doses, suppresses hepatic glucose production by activating a conserved regulatory pathway encompassing let-7, TET3, and a fetal isoform of hepatocyte nuclear factor 4 alpha (HNF4α). We demonstrate that metformin no longer has potent antidiabetic actions in a liver-specific let-7 loss-of-function mouse model and that hepatic delivery of let-7 ameliorates hyperglycemia and improves glucose homeostasis. Our results thus reveal an important role of the hepatic let-7/TET3/HNF4α axis in mediating the therapeutic effects of metformin and suggest that targeting this axis may be a potential therapeutic for diabetes.


Assuntos
Hiperglicemia , Metformina , Animais , Modelos Animais de Doenças , Glucose/metabolismo , Hepatócitos/metabolismo , Hiperglicemia/metabolismo , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Fígado/metabolismo , Metformina/uso terapêutico , Camundongos
7.
J Cereb Blood Flow Metab ; 42(7): 1259-1271, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35078350

RESUMO

The brain is highly complex with diverse structural characteristics in accordance with specific functions. Accordingly, differences in regional function, cellular compositions, and active metabolic pathways may link to differences in glucose metabolism at different brain regions. In the current study, we optimized an acute biopsy punching method and characterized region-specific glucose metabolism of rat and mouse brain by a Seahorse XFe96 analyzer. We demonstrated that 0.5 mm diameter tissue punches from 180-µm thick brain sections allow metabolic measurements of anatomically defined brain structures using Seahorse XFe96 analyzer. Our result indicated that the cerebellum displays a more quiescent phenotype of glucose metabolism than cerebral cortex, basal ganglia, and hippocampus. In addition, the cerebellum has higher AMPK activation than other brain regions evidenced by the expression of pAMPK, upstream pLKB1, and downstream pACC. Furthermore, rodent brain has relatively low mitochondrial oxidative phosphorylation efficiency with up to 30% of respiration linked to proton leak. In summary, our study discovered region-specific glucose metabolic profile and relative high proton leak coupled respiration in the brain. Our study warrants future research on spatial mapping of the brain glucose metabolism in physiological and pathological conditions and exploring the mechanisms and significance of mitochondrial uncoupling in the brain.


Assuntos
Glucose , Smegmamorpha , Animais , Encéfalo/metabolismo , Glucose/metabolismo , Metaboloma , Camundongos , Prótons , Ratos , Roedores/metabolismo , Smegmamorpha/metabolismo
8.
Neurol Res ; 43(7): 570-581, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33688799

RESUMO

BACKGROUND: The cerebellum's involvement in AD has been under-appreciated by historically labeling as a normal control in AD research. METHODS: We determined the involvement of the cerebellum in AD progression. Postmortem human and APPswe/PSEN1dE9 mice cerebellums were used to assess the cerebellar Purkinje cells (PC) by immunohistochemistry. The locomotor and spatial cognitive functions were assessed in 4- to 5-month-old APPswe/PSEN1dE9 mice. Aß plaque and APP processing were determined in APPswe/PSEN1dE9 mice at different age groups by immunohistochemistry and Western blot. RESULTS: We observed loss of cerebellar PC in mild cognitive impairment and AD patients compared with cognitively normal controls. A strong trend towards PC loss was found in AD mice as early as 5 months. Impairment of balance beam and rotorod performance, but no spatial learning and memory dysfunction was observed in AD mice at 4-5 months. Aß plaque in the cerebral cortex was evidenced in AD mice at 2 months and dramatically increased at 6 months. Less and smaller Aß plaques were observed in the cerebellum than in the cerebrum of AD mice. Similar intracellular APP staining was observed in the cerebellum and cerebrum of AD mice at 2 to 10 months. Similar expression of full-length APP and C-terminal fragments were indicated in the cerebrum and cerebellum of AD mice during aging. DISCUSSION: Our study in post-mortem human brains and transgenic AD mice provided neuropathological and functional evidence that cerebellar dysfunction may occur at the early stage of AD and likely independent of Aß plaque.


Assuntos
Doença de Alzheimer/metabolismo , Encéfalo/patologia , Placa Amiloide/metabolismo , Células de Purkinje/patologia , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Encéfalo/metabolismo , Cognição/fisiologia , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Modelos Animais de Doenças , Humanos , Camundongos Transgênicos , Placa Amiloide/patologia
9.
Antioxidants (Basel) ; 9(6)2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32630431

RESUMO

This study determined whether antioxidant supplementation is a viable complement to exercise regimens in improving cognitive and motor performance in a mouse model of Alzheimer's disease risk. Starting at 12 months of age, separate groups of male and female mice expressing human Apolipoprotein E3 (GFAP-ApoE3) or E4 (GFAP-ApoE4) were fed either a control diet or a diet supplemented with vitamins E and C. The mice were further separated into a sedentary group or a group that followed a daily exercise regimen. After 8 weeks on the treatments, the mice were administered a battery of functional tests including tests to measure reflex and motor, cognitive, and affective function while remaining on their treatment. Subsequently, plasma inflammatory markers and catalase activity in brain regions were measured. Overall, the GFAP-ApoE4 mice exhibited poorer motor function and spatial learning and memory. The treatments improved balance, learning, and cognitive flexibility in the GFAP-ApoE3 mice and overall the GFAP-ApoE4 mice were not responsive. The addition of antioxidants to supplement a training regimen only provided further benefits to the active avoidance task, and there was no antagonistic interaction between the two interventions. These outcomes are indicative that there is a window of opportunity for treatment and that genotype plays an important role in response to interventions.

10.
PLoS One ; 15(6): e0234571, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32525922

RESUMO

Metformin, an anti-diabetes drug, has been recently emerging as a potential "anti-aging" intervention based on its reported beneficial actions against aging in preclinical studies. Nonetheless, very few metformin studies using mice have determined metformin concentrations and many effects of metformin have been observed in preclinical studies using doses/concentrations that were not relevant to therapeutic levels in human. We developed a liquid chromatography-tandem mass spectrometry protocol for metformin measurement in plasma, liver, brain, kidney, and muscle of mice. Young adult male and female C57BL/6 mice were voluntarily treated with metformin of 4 mg/ml in drinking water which translated to the maximum dose of 2.5 g/day in humans. A clinically relevant steady-state plasma metformin concentrations were achieved at 7 and 30 days after treatment in male and female mice. Metformin concentrations were slightly higher in muscle than in plasma, while, ~3 and 6-fold higher in the liver and kidney than in plasma, respectively. Low metformin concentration was found in the brain at ~20% of the plasma level. Furthermore, gender difference in steady-state metformin bio-distribution was observed. Our study established steady-state metformin levels in plasma, liver, muscle, kidney, and brain of normoglycemic mice treated with a clinically relevant dose, providing insight into future metformin preclinical studies for potential clinical translation.


Assuntos
Metformina/farmacocinética , Animais , Encéfalo/metabolismo , Cromatografia Líquida , Feminino , Rim/metabolismo , Fígado/metabolismo , Masculino , Metformina/administração & dosagem , Metformina/sangue , Camundongos , Camundongos Endogâmicos C57BL , Músculos/metabolismo , Espectrometria de Massas em Tandem , Distribuição Tecidual
11.
Geroscience ; 42(1): 97-116, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31897861

RESUMO

Metformin is the safest and the most widely prescribed first-line therapy for managing hyperglycemia due to different underlying causes, primarily type 2 diabetes mellitus. In addition to its euglycemic properties, metformin has stimulated a wave of clinical trials to investigate benefits on aging-related diseases and longevity. Such an impact on the lifespan extension would undoubtedly expand the therapeutic utility of metformin regardless of glycemic status. However, there is a scarcity of studies evaluating whether metformin has differential cognitive effects across age, sex, glycemic status, metformin dose, and duration of metformin treatment and associated pathological conditions. By scrutinizing the available literature on animal and human studies for metformin and brain function, we expect to shed light on the potential impact of metformin on cognition across age, sex, and pathological conditions. This review aims to provide readers with a broader insight of (a) how metformin differentially affects cognition and (b) why there is a need for more translational and clinical studies examining multifactorial interactions. The outcomes of such comprehensive studies will streamline precision medicine practices, avoiding "fit for all" approach, and optimizing metformin use for longevity benefit irrespective of hyperglycemia.


Assuntos
Diabetes Mellitus Tipo 2 , Metformina , Animais , Cognição , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Hipoglicemiantes/uso terapêutico , Longevidade , Metformina/uso terapêutico
12.
Aging Dis ; 10(5): 949-963, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31595194

RESUMO

Metformin is currently the most effective treatment for type-2 diabetes. The beneficial actions of metformin have been found even beyond diabetes management and it has been considered as one of the most promising drugs that could potentially slow down aging. Surprisingly, the effect of metformin on brain function and metabolism has been less explored given that brain almost exclusively uses glucose as substrate for energy metabolism. We determined the effect of metformin on locomotor and cognitive function in normoglycemic mice. Metformin enhanced locomotor and balance performance, while induced anxiolytic effect and impaired cognitive function upon chronic treatment. We conducted in vitro assays and metabolomics analysis in mice to evaluate metformin's action on the brain metabolism. Metformin decreased ATP level and activated AMPK pathway in mouse hippocampus. Metformin inhibited oxidative phosphorylation and elevated glycolysis by inhibiting mitochondrial glycerol-3-phosphate dehydrogenase (mGPDH) in vitro at therapeutic doses. In summary, our study demonstrated that chronic metformin treatment affects brain bioenergetics with compound effects on locomotor and cognitive brain function in non-diabetic mice.

13.
Brain Res ; 1723: 146378, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31425677

RESUMO

Cholesterol sulfate (CS) is one of the most important known sterol sulfates in human plasma and it is present as a normal constituent in a variety of human tissues. In both the brain and periphery, CS serves as a substrate for the synthesis of sulfonated adrenal steroids such as pregnenolone sulfate and dehydroepiandrosterone (DHEA) sulfate and as a constituent of many biological membranes including red blood cells where it functions as a stabilizing agent. It also acts as an endogenous regulator of cholesterol synthesis. However, the role of CS in brain metabolism and neurological disorder is unclear. In the current study we investigated the neuroprotective action of CS as well as its role in brain energy metabolism. The neuroprotective effect of CS and its role on cell metabolism were determined in primary astrocyte prepared from the cortex of postnatal day 0-2 C57BL/6 pups and a hippocampal HT-22 cell line using Calcein AM and MTT cell viability assay, flow cytometry, Seahorse extracellular flux analysis, and metabolism assay kits. We found that CS attenuates glutamate and rotenone induced cell death in HT-22 cells, decrease glutamate induced mitochondria membrane potential collapse, and reactive oxygen species production. Additionally, CS activates the Akt/Bcl2 pathway. We observed that CS impacts astrocyte metabolism by increasing mitochondrial phosphorylation, ATP, and glycogen contents. Our study demonstrated that CS modulates brain energy metabolism and its neuroprotective effects might be due to the activation of Akt signaling or its ability to decrease reactive oxygen species production.


Assuntos
Astrócitos/metabolismo , Ésteres do Colesterol/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ésteres do Colesterol/farmacologia , Metabolismo Energético/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacologia , Pregnenolona/metabolismo , Cultura Primária de Células , Espécies Reativas de Oxigênio/metabolismo
14.
J Neurosci Methods ; 320: 50-63, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30904500

RESUMO

BACKGROUND: Primary astrocyte cultures have been used for decades to study astrocyte functions in health and disease. The current primary astrocyte cultures are mostly maintained in serum-containing medium which produces astrocytes with a reactive phenotype as compared to in vivo quiescent astrocytes. The aim of this study was to establish a serum-free astrocyte culture medium that maintains primary astrocytes in a quiescent state. NEW METHOD: Serum free astrocyte base medium (ABM) supplemented with basic fibroblast growth factor 2 (FGF2) and epidermal growth factor (EGF) (ABM-FGF2-EGF) or serum supplemented DMEM (MD-10%FBS) was used to culture primary astrocytes isolated from cerebral cortex of postnatal day 1 C57BL/6 mice. RESULTS: Compared to astrocytes cultured in MD-10%FBS medium, astrocytes in ABM-FGF2-EGF had higher process bearing morphologies similar to in vivo astrocytes. Western blot, immunostaining, quantitative polymerase chain reaction and metabolic assays revealed that astrocytes maintained in ABM-FGF2-EGF had enhanced glycolytic metabolism, higher glycogen content, lower GFAP expression, increased glutamine synthase, and glutamate transporter-1 mRNA levels as compared to astrocytes cultured in MD-10% FBS medium. COMPARISON TO EXISTING METHODS: These observations suggest that astrocytes cultured in ABM-FGF2-EGF media compared to the usual FBS media promote quiescent and biosynthetic phenotype similar to in vivo astrocytes. CONCLUSION: This media provides a novel method for studying astrocytes functions in vitro under physiological and pathological conditions.


Assuntos
Astrócitos , Fator de Crescimento Epidérmico , Fatores de Crescimento de Fibroblastos , Neurociências/métodos , Cultura Primária de Células/métodos , Animais , Bovinos , Células Cultivadas , Sangue Fetal
15.
Exp Gerontol ; 94: 69-72, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-27939444

RESUMO

Age-related declines in motor and cognitive function have been associated with increases in oxidative stress. Accordingly, interventions capable of reducing the oxidative burden would be capable of preventing or reducing functional declines occurring during aging. Popular interventions such as antioxidant intake and moderate exercise are often recommended to attain healthy aging and have the capacity to alter redox burden. This review is intended to summarize the outcomes of antioxidant supplementation (more specifically of vitamins C and E) and exercise training on motor and cognitive declines during aging, and on measures of oxidative stress. Additionally, we will address whether co-implementation of these two types of interventions can potentially further their individual benefits. Together, these studies highlight the importance of using translationally-relevant parameters for interventions and to study their combined outcomes on healthy brain aging.


Assuntos
Envelhecimento/efeitos dos fármacos , Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Encéfalo/efeitos dos fármacos , Exercício Físico , Estresse Oxidativo/efeitos dos fármacos , Vitamina E/farmacologia , Fatores Etários , Envelhecimento/metabolismo , Envelhecimento/patologia , Envelhecimento/psicologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/fisiopatologia , Envelhecimento Cognitivo , Envelhecimento Saudável , Humanos
16.
Behav Brain Res ; 305: 37-45, 2016 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26892275

RESUMO

Motor dysfunction has been found to be predictive of cognitive dysfunction in Alzheimer's disease and to occur earlier than cognitive impairments. While apolipoprotein (Apo) E4 has been associated with cognitive impairments, it remains unclear whether it also increases risk for motor dysfunction. Exercise and antioxidants are often recommended to reduce cognitive declines, however it is unclear whether they can successfully improve motor impairments. This study was designed to determine the extent of the impact of apolipoprotein genotype on motor function, and whether interventions such as exercise and antioxidant intake can improve motor function. This study is the first to identify the nature of the interaction between antioxidant intake and exercise using a mouse model expressing either the human ApoE3 or ApoE4 isoforms under glial fibrillary acid protein promoter (GFAP-ApoE3 and GFAP-ApoE4 mice). The mice were fed either a control diet or the control diet supplemented with vitamins E and C (1.12 IU/g diet α-tocopheryl acetate and 1.65mg/g ascorbic acid). Each genotype/diet group was further divided into a sedentary group or a group that followed a 6 days a week exercise regimen. After 8 weeks on their respective treatment, the mice were administered a battery of motor tests to measure reflexes, strength, coordination and balance. GFAP-ApoE4 mice exhibited impaired motor learning and diminished strength compared to the GFAP-ApoE3 mice. Exercise alone was more efficient at improving motor function and reversing ApoE4-associated impairments than antioxidants alone, even though improvements were rather subtle. Contrarily to expected outcomes, combination of antioxidants and exercise did not yield further improvements of motor function. Interestingly, antioxidants antagonized the beneficial effects of exercise on strength. These data suggest that environmental and genetic factors influence the outcome of interventions on motor function and should be investigated more thoroughly and taken into consideration when implementing changes in lifestyles.


Assuntos
Apolipoproteína E4/genética , Proteína Glial Fibrilar Ácida/genética , Transtornos dos Movimentos/genética , Transtornos dos Movimentos/reabilitação , Análise de Variância , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Apolipoproteína E4/metabolismo , Peso Corporal/efeitos dos fármacos , Peso Corporal/genética , Modelos Animais de Doenças , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/genética , Terapia por Exercício , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Locomoção/efeitos dos fármacos , Locomoção/genética , Camundongos , Camundongos Transgênicos , Transtornos dos Movimentos/tratamento farmacológico , Transtornos dos Movimentos/terapia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Desempenho Psicomotor/efeitos dos fármacos , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/genética , Reflexo/efeitos dos fármacos
17.
Small ; 10(13): 2625-36, 2014 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-24664643

RESUMO

Herein, a unique approach to dispose of human hair by pyrolizing it in a regulated environment is presented, yielding highly porous, conductive hair carbons with heteroatoms and high surface area. α-keratin in the protein network of hair serves as a precursor for the heteroatoms and carbon. The carbon framework is ingrained with heteroatoms such as nitrogen and sulfur, which otherwise are incorporated externally through energy-intensive, hazardous, chemical reactions using proper organic precursors. This judicious transformation of organic-rich waste not only addresses the disposal issue, but also generates valuable functional carbon materials from the discard. This unique synthesis strategy involving moderate activation and further graphitization enhances the electrical conductivity, while still maintaining the precious heteroatoms. The effect of temperature on the structural and functional properties is studied, and all the as-obtained carbons are applied as metal-free catalysts for the oxygen reduction reaction (ORR). Carbon graphitized at 900 °C emerges as a superior ORR electrocatalyst with excellent electrocatalytic performance, high selectivity, and long durability, demonstrating that hair carbon can be a promising alternative for costly Pt-based electrocatalysts in fuel cells. The ORR performance can be discussed in terms of heteroatom doping, surface properties, and electrical conductivity of the resulting porous hair carbon materials.


Assuntos
Carbono/química , Cabelo/química , Humanos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Propriedades de Superfície
18.
J Ayurveda Integr Med ; 4(1): 28-32, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23741159

RESUMO

BACKGROUND: Sleep disturbances and decline in the physical functionality are common conditions associated with aging. Pharmacological treatment of sleep disturbances can be associated with various adverse effects. Short term trials of Yoga on sleep have shown beneficial effects. OBJECTIVES: To evaluate the effect of long-term Yoga exercises on sleep quality and quality of life (QOL) in the elderly. MATERIALS AND METHODS: This was a cross-sectional study in which data were collected from elderly people aged 60 years or more living in Nagpur city. We employed two types of survey questionnaires: Pittsburgh sleep quality index (PSQI) and QOL Leiden-Padua (LEIPAD) Questionnaire. A total of 65 elderly men and women who signed an informed consent and completed questionnaires were included in the study. Sleep quality score PSQI and QOL (LEIPAD Questionnaire) score of the study group were evaluated and compared with the control group using Mann-Whitney U test. RESULTS: Total PSQI score in Yoga group was lower than that of the control group. Also various QOL scores of the Yoga groups were higher than the control group. CONCLUSION: Addition of regular Yoga exercises in the daily routine of elderly people can help to achieve good sleep quality as well as improve the QOL.

19.
Brain Res ; 1514: 123-7, 2013 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-23415935

RESUMO

Phytoestrogens are plant-derived compounds found mainly in soy with known estrogenic properties and a potential for benefits to human health. Increased intake in phytoestrogens stemmed from the search for safe alternatives to hormone replacement therapies. Based on epidemiologic evidence comparing Western and Asian populations and clinical studies, phytoestrogens show promise to improve health and brain function. This review is focused on the effects of phytoestrogens on cognition by examining clinical and animal studies, with special attention placed on (1) a window of therapeutic opportunity which may explain the discrepancy among studies, and (2) whether a sex/gender difference exists in response to phytoestrogen intake and what the possible underlying mechanisms may be.


Assuntos
Cognição/efeitos dos fármacos , Suplementos Nutricionais , Fitoestrógenos/farmacologia , Preparações de Plantas/uso terapêutico , Caracteres Sexuais , Animais , Feminino , Humanos , Masculino
20.
Int J Pharm ; 432(1-2): 63-74, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22531856

RESUMO

Cancer cells reflect higher level of ROS in comparison to the normal cell, so they become more vulnerable to further oxidative stress induced by exogenous ROS-generating agents. Through this a novel therapeutic strategy has evolved, which involves the delivery of redox cycler-doxorubicin (DOX) to the mitochondria of cancer cell where it acts as a source of exogenous ROS production. The purpose of this study is to develop a liposomal preparation which exhibits a propensity to selectively target cancer cell along with the potential of delivering drug to mitochondria of cell. We have rendered liposomes mitocancerotropic (FA-MTLs) by their surface modification with dual ligands, folic acid (FA) for cancer cell targeting and triphenylphosphonium (TPP) cations for mitochondria targeting. The cytotoxicity, ROS production and cell uptake of doxorubicin loaded liposomes were evaluated in FR (+) KB cells and found to be increased considerably with FA-MTLs in comparison to folic acid appended, mitochondria targeted and non-targeted liposomes. As confirmed by confocal microscopy, the STPP appended liposomes delivered DOX to mitochondria of cancer cell and also showed higher ROS production and cytotoxicity in comparison to folic acid appended and non-targeted liposomes. Most importantly, mitocancerotropic liposomes showed superior activity over mitochondria targeted liposomes which confirm the synergistic effect imparted by the presence of dual ligands - folic acid and TPP on the enhancement of cellular and mitochondrial delivery of doxorubicin in KB cells.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Receptores de Folato com Âncoras de GPI/metabolismo , Neoplasias/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Colesterol/química , Ácido Fólico/química , Humanos , Lipossomos , Mitocôndrias/metabolismo , Neoplasias/tratamento farmacológico , Oxirredução , Polietilenoglicóis/química , Espécies Reativas de Oxigênio/metabolismo
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