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1.
Sci Rep ; 13(1): 17692, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848670

RESUMO

Emerging technological tools like Artificial Intelligence-based Chatbots, digital educational alternatives and market-driven educational systems pose a challenge to the fundamental aim of the higher education system; comprehensive education for well-being. Therefore, this research aims to devise and evaluate strategies to impart new-age competencies to innovate socially and morally appropriate solutions in a modern competitive innovative society. The 8-month-long immersive learning framework (ILF), was designed based on the volatility, uncertainty, complexity, and ambiguity (VUCA) paradigm. The framework was evaluated with 133 newly joined postgraduate students doing their science or arts programmes from a higher education institution in Kerala, India. The outcome variables included well-being, depressive symptoms, personality patterns, and sub-domains of philosophy of human nature. The follow-up scores showed a significant improvement in well-being (Mean difference: 1.15, p = 0.005), trustworthiness (Mean difference: 14.74, p = 0.000), strength of will (Mean difference: 10.11, p = 0.000), altruism (Mean difference: 12.85, p = 0.000), and independence (Mean difference: 11.93, p = 0.000). Depression scores did not improve significantly. However, the intervention shielded them from the adjustment issues that often accompany any transition. The ILF framework can help students develop their personal and professional selves if it is implemented collaboratively in a reflective setting. It can also instil moral rectitude and a prosocial mindset.


Assuntos
Inteligência Artificial , Objetivos , Humanos , Aprendizagem , Estudantes , Instituições Acadêmicas
2.
Front Cell Dev Biol ; 9: 663456, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34095131

RESUMO

Adult hippocampal neurogenesis is stimulated acutely following traumatic brain injury (TBI). However, many hippocampal neurons born after injury develop abnormally and the number that survive long-term is debated. In experimental TBI, insulin-like growth factor-1 (IGF1) promotes hippocampal neuronal differentiation, improves immature neuron dendritic arbor morphology, increases long-term survival of neurons born after TBI, and improves cognitive function. One potential downstream mediator of the neurogenic effects of IGF1 is mammalian target of rapamycin (mTOR), which regulates proliferation as well as axonal and dendritic growth in the CNS. Excessive mTOR activation is posited to contribute to aberrant plasticity related to posttraumatic epilepsy, spurring preclinical studies of mTOR inhibitors as therapeutics for TBI. The degree to which pro-neurogenic effects of IGF1 depend upon upregulation of mTOR activity is currently unknown. Using immunostaining for phosphorylated ribosomal protein S6, a commonly used surrogate for mTOR activation, we show that controlled cortical impact TBI triggers mTOR activation in the dentate gyrus in a time-, region-, and injury severity-dependent manner. Posttraumatic mTOR activation in the granule cell layer (GCL) and dentate hilus was amplified in mice with conditional overexpression of IGF1. In contrast, delayed astrocytic activation of mTOR signaling within the dentate gyrus molecular layer, closely associated with proliferation, was not affected by IGF1 overexpression. To determine whether mTOR activation is necessary for IGF1-mediated stimulation of posttraumatic hippocampal neurogenesis, wildtype and IGF1 transgenic mice received the mTOR inhibitor rapamycin daily beginning at 3 days after TBI, following pulse labeling with bromodeoxyuridine. Compared to wildtype mice, IGF1 overexpressing mice exhibited increased posttraumatic neurogenesis, with a higher density of posttrauma-born GCL neurons at 10 days after injury. Inhibition of mTOR did not abrogate IGF1-stimulated enhancement of posttraumatic neurogenesis. Rather, rapamycin treatment in IGF1 transgenic mice, but not in WT mice, increased numbers of cells labeled with BrdU at 3 days after injury that survived to 10 days, and enhanced the proportion of posttrauma-born cells that differentiated into neurons. Because beneficial effects of IGF1 on hippocampal neurogenesis were maintained or even enhanced with delayed inhibition of mTOR, combination therapy approaches may hold promise for TBI.

3.
Transl Res ; 231: 13-23, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33460824

RESUMO

Oligodendrocyte progenitor cells (OPCs) in the infant brain give rise to mature oligodendrocytes that myelinate CNS axons. OPCs are particularly vulnerable to oxidative stress that occurs in many forms of brain injury. One common cause of infant brain injury is neonatal intraventricular hemorrhage (IVH), which releases blood into the CSF and brain parenchyma of preterm infants. Although blood contains the powerful oxidant hemoglobin, the direct effects of hemoglobin on OPCs have not been studied. We utilized a cell culture system to test if hemoglobin induced free radical production and mitochondrial dysfunction in OPCs. We also tested if phenelzine (PLZ), an FDA-approved antioxidant drug, could protect OPCs from hemoglobin-induced oxidative stress. OPCs were isolated from Sprague Dawley rat pups and exposed to hemoglobin with and without PLZ. Outcomes assessed included intracellular reactive oxygen species levels using 2',7'-dichlorodihydrofluorescein diacetate (DCF-DA) fluorescent dye, oxygen consumption using the XFe96 Seahorse assay, and proliferation measured by BrdU incorporation assay. Hemoglobin induced oxidative stress and impaired mitochondrial function in OPCs. PLZ treatment reduced hemoglobin-induced oxidative stress and improved OPC mitochondrial bioenergetics. The effects of hemoglobin and PLZ on OPC proliferation were not statistically significant, but showed trends towards hemoglobin reducing OPC proliferation and PLZ increasing OPC proliferation (P=0.06 for both effects). Collectively, our results indicate that hemoglobin induces mitochondrial dysfunction in OPCs and that antioxidant therapy reduces these effects. Therefore, antioxidant therapy may hold promise for white matter diseases in which hemoglobin plays a role, such as neonatal IVH.


Assuntos
Hemoglobinas/farmacologia , Mitocôndrias/efeitos dos fármacos , Oligodendroglia/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Proliferação de Células , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , L-Lactato Desidrogenase , Mitocôndrias/metabolismo , Consumo de Oxigênio , Fenelzina/farmacologia , Gravidez , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio , Células-Tronco
4.
F1000Res ; 9: 700, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32832072

RESUMO

Background: The burden of disability on individuals and society is enormous in India, and informal care systems try to reduce this burden. This study investigated the association between neighbourhood cohesion and disability in a community-based population in Kerala, India. To the best of our knowledge, no previous studies have examined this association in India.   Methods: A cross-sectional household survey was conducted with 997 participants aged 30 years and above, in Kerala. Neighbourhood cohesion was assessed by three scales: trust, community participation, and perceived safety. Functional ability was measured by WHODAS 2.0. Explanatory covariates included chronic disease conditions, age, gender, education, income, and mental health conditions. Results: Of 997 participants (37% male; mean age, 53.9 [range, 30-90] years), the majority were married or cohabiting. Univariate analysis showed functional ability to be positively associated with most demographic and health characteristics. However, after adjustment, only social cohesion, age, income, education, chronic diseases and mental health conditions remained significant. Mediation analysis showed the effect of personal and health characteristics on functional ability as mediated by social cohesion. Conclusion: Social cohesion is an important moderator of functional ability. Interventions targeting the creation of stronger ties among neighbours and a sense of belonging should be scaled-up and evaluated in future research.


Assuntos
Nível de Saúde , Características de Residência , Identificação Social , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Pessoas com Deficiência , Feminino , Humanos , Índia , Masculino , Saúde Mental , Pessoa de Meia-Idade , Inquéritos e Questionários
5.
J Vis Exp ; (160)2020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32658201

RESUMO

Neural stem cell (NSC) therapy is an emerging innovative treatment for stroke, traumatic brain injury and neurodegenerative disorders. As compared to intracranial delivery, intra-arterial administration of NSCs is less invasive and produces a more diffuse distribution of NSCs within the brain parenchyma. Further, intra-arterial delivery allows the first-pass effect in the brain circulation, lessening the potential for trapping of cells in peripheral organs, such as liver and spleen, a complication associated with peripheral injections. Here, we detail the methodology, in both mice and rats, for delivery of NSCs through the common carotid artery (mouse) or external carotid artery (rat) to the ipsilateral hemisphere after an ischemic stroke. Using GFP-labeled NSCs, we illustrate the widespread distribution achieved throughout the rodent ipsilateral hemisphere at 1 d, 1 week and 4 weeks after postischemic delivery, with a higher density in or near the ischemic injury site. In addition to long-term survival, we show evidence of differentiation of GFP-labeled cells at 4 weeks. The intra-arterial delivery approach described here for NSCs can also be used for administration of therapeutic compounds, and thus has broad applicability to varied CNS injury and disease models across multiple species.


Assuntos
Isquemia Encefálica/cirurgia , Injeções Intra-Arteriais/métodos , Células-Tronco Neurais/metabolismo , Transplante de Células-Tronco/métodos , Animais , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Células-Tronco Neurais/citologia , Ratos , Ratos Wistar
6.
J Neurotrauma ; 36(8): 1252-1263, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30417732

RESUMO

Mild traumatic brain injuries (mTBI), accounting for more than 80% of TBIs, can cause cognitive and behavioral impairments, the severity and duration of which increase after additional mTBIs. While mTBI does not cause widespread neuronal death, the mechanisms underlying increased cellular susceptibility to subsequent head impacts remain unknown. To investigate the hypothesis that altered mitochondrial bioenergetics underlie cellular vulnerability to repeated insults, we employed a mouse model of mild closed head injury (CHI) to examine mitochondrial function and oxidative stress, because these mechanisms are often intertwined. Mitochondrial respiration was assayed (Seahorse XFe24 Flux Analyzer) from cortex and hippocampus collected at 6 h, 24 h, 48 h, and 96 h post-injury. State III (adenosine diphosphate [ADP]-mediated) respiration was significantly decreased in the hippocampal mitochondria of the CHI group compared with sham at 48 h post-injury. Further, cortex-derived mitochondria exhibited a decrease in State III respiration at 24 h and 48 h post-injury. No significant differences were observed at 6 h or 96 h post-injury in either region of interest. A second CHI repeated either 48 h or 96 h after the first did not worsen State III respiration at 48 h after the final injury compared with a single CHI, but CHI repeated at a 48 h interval prolonged cortical mitochondrial dysfunction to 96 h after the final injury. Markers of oxidative stress were significantly elevated after two CHIs delivered 48 h apart, but not after single CHI or two CHI delivered 96 h apart. This study establishes that mTBI results in early mitochondrial dysfunction, which may be a determinant for cellular vulnerability to repeated head impacts. Thus, therapies targeting mitochondrial impairment could improve outcomes after repeated mTBI.


Assuntos
Concussão Encefálica/fisiopatologia , Encéfalo/fisiopatologia , Mitocôndrias/metabolismo , Animais , Encéfalo/metabolismo , Concussão Encefálica/metabolismo , Respiração Celular/fisiologia , Metabolismo Energético/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/fisiologia
7.
Restor Neurol Neurosci ; 36(4): 559-569, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29889090

RESUMO

BACKGROUND: Traumatic brain injury can result in lasting cognitive dysfunction due to degeneration of mature hippocampal neurons as well as the loss of immature neurons within the dentate gyrus. While endogenous neurogenesis affords a partial recovery of the immature neuron population, hippocampal neurogenesis may be enhanced through therapeutic intervention. Insulin-like growth factor-1 (IGF-1) has the potential to improve cognitive function and promote neurogenesis after TBI, but its short half-life in the systemic circulation makes it difficult to maintain a therapeutic concentration. IGF-1 modified with a polyethylene glycol moiety (PEG-IGF-1) exhibits improved stability and half-life while retaining its ability to enter the brain from the periphery, increasing its viability as a translational approach. OBJECTIVE: The goal of this study was to evaluate the ability of systemic PEG-IGF-1 administration to attenuate acute neuronal loss and stimulate the recovery of hippocampal immature neurons in brain-injured mice. METHODS: In a series of studies utilizing a well-established contusion brain injury model, PEG-IGF-1 was administered subcutaneously after injury. Serum levels of PEG were verified using ELISA and histological staining was used to investigate numbers of degenerating neurons and cortical contusion size at 24 h after injury. Immunofluorescent staining was used to evaluate numbers of immature neurons at 10 d after injury. RESULTS: Although subcutaneous injections of PEG-IGF-1 increased serum IGF-1 levels in a dose-dependent manner, no effects were observed on cortical contusion size, neurodegeneration within the dentate gyrus, or recovery of hippocampal immature neuron numbers. CONCLUSIONS: In contrast to its efficacy in rodent models of neurodegenerative diseases, PEG- IGF-1 was not effective in ameliorating early neuronal loss after contusion brain trauma.


Assuntos
Lesões Encefálicas Traumáticas/tratamento farmacológico , Fator de Crescimento Insulin-Like I/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Polietilenoglicóis/uso terapêutico , Análise de Variância , Animais , Lesões Encefálicas Traumáticas/patologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Proteínas do Domínio Duplacortina , Fluoresceínas/farmacocinética , Lateralidade Funcional , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/patologia , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neuropeptídeos/metabolismo
8.
PLoS One ; 11(7): e0159442, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27427961

RESUMO

Millions of mild traumatic brain injuries (TBIs) occur every year in the United States, with many people subject to multiple head injuries that can lead to chronic behavioral dysfunction. We previously reported that mild TBI induced using closed head injuries (CHI) repeated at 24h intervals produced more acute neuron death and glial reactivity than a single CHI, and increasing the length of time between injuries to 48h reduced the cumulative acute effects of repeated CHI. To determine whether repeated CHI is associated with behavioral dysfunction or persistent cellular damage, mice receiving either five CHI at 24h intervals, five CHI at 48h intervals, or five sham injuries at 24h intervals were evaluated across a 10 week period after injury. Animals with repeated CHI exhibited motor coordination and memory deficits, but not gait abnormalities when compared to sham animals. At 10wks post-injury, no notable neuron loss or glial reactivity was observed in the cortex, hippocampus, or corpus callosum. Argyrophilic axons were found in the pyramidal tract of some injured animals, but neither silver stain accumulation nor inflammatory responses in the injury groups were statistically different from the sham group in this region. However, argyrophilic axons, microgliosis and astrogliosis were significantly increased within the optic tract of injured animals. Repeated mild CHI also resulted in microgliosis and a loss of neurofilament protein 200 in the optic nerve. Lengthening the inter-injury interval from 24h to 48h did not effectively reduce these behavioral or cellular responses. These results suggest that repeated mild CHI results in persistent behavioral dysfunction and chronic pathological changes within the visual system, neither of which was significantly attenuated by lengthening the inter-injury interval from 24h to 48h.


Assuntos
Concussão Encefálica/fisiopatologia , Córtex Cerebral/fisiopatologia , Corpo Caloso/fisiopatologia , Traumatismos Cranianos Fechados/fisiopatologia , Hipocampo/fisiopatologia , Transtornos da Memória/fisiopatologia , Animais , Concussão Encefálica/metabolismo , Concussão Encefálica/patologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Corpo Caloso/metabolismo , Corpo Caloso/patologia , Modelos Animais de Doenças , Expressão Gênica , Gliose/metabolismo , Gliose/patologia , Gliose/fisiopatologia , Traumatismos Cranianos Fechados/metabolismo , Traumatismos Cranianos Fechados/patologia , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Transtornos da Memória/metabolismo , Transtornos da Memória/patologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Neurofilamentos/genética , Proteínas de Neurofilamentos/metabolismo , Neuroglia/metabolismo , Neuroglia/patologia , Neurônios/metabolismo , Neurônios/patologia , Nervo Óptico/metabolismo , Nervo Óptico/patologia , Nervo Óptico/fisiopatologia , Trato Óptico/metabolismo , Trato Óptico/patologia , Trato Óptico/fisiopatologia , Desempenho Psicomotor , Tratos Piramidais/metabolismo , Tratos Piramidais/patologia , Tratos Piramidais/fisiopatologia
9.
Toxicol Appl Pharmacol ; 280(1): 127-37, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25062774

RESUMO

Skin cancer is one of the most commonly diagnosed cancers in the United States. Exposure to ultraviolet-B (UVB) radiation induces inflammation and photocarcinogenesis in mammalian skin. Cyanidin-3-glucoside (C3G), a member of the anthocyanin family, is present in various vegetables and fruits especially in edible berries, and displays potent antioxidant and anticarcinogenic properties. In this study, we have assessed the in vivo effects of C3G on UVB irradiation induced chronic inflammatory responses in SKH-1 hairless mice, a well-established model for UVB-induced skin carcinogenesis. Here, we show that C3G inhibited UVB-induced skin damage and inflammation in SKH-1 hairless mice. Our results indicate that C3G inhibited glutathione depletion, lipid peroxidation and myeloperoxidation in mouse skin by chronic UVB exposure. C3G significantly decreased the production of UVB-induced pro-inflammatory cytokines, such as IL-6 and TNF-α, associated with cutaneous inflammation. Likewise, UVB-induced inflammatory responses were diminished by C3G as observed by a remarkable reduction in the levels of phosphorylated MAP kinases, Erk1/2, p38, JNK1/2 and MKK4. Furthermore, C3G also decreased UVB-induced cyclooxygenase-2 (COX-2), PGE2 and iNOS levels, which are well-known key mediators of inflammation and cancer. Treatment with C3G inhibited UVB-induced nuclear translocation of NF-κB and degradation of IκBα in mice skin. Immunofluorescence assay revealed that topical application of C3G inhibited the expression of 8-hydroxy-2'-deoxyguanosine, proliferating cell nuclear antigen, and cyclin D1 in chronic UVB exposed mouse skin. Collectively, these data indicates that C3G can provide substantial protection against the adverse effects of UVB radiation by modulating UVB-induced MAP kinase and NF-κB signaling pathways.


Assuntos
Antocianinas/farmacologia , Glucosídeos/farmacologia , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , NF-kappa B/antagonistas & inibidores , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Animais , Relação Dose-Resposta a Droga , Feminino , Inflamação/metabolismo , Inflamação/patologia , Inflamação/prevenção & controle , Camundongos , Camundongos Pelados , Proteínas Quinases Ativadas por Mitógeno/fisiologia , NF-kappa B/fisiologia , Estresse Oxidativo/fisiologia , Distribuição Aleatória , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Transdução de Sinais/efeitos da radiação , Absorção Cutânea/efeitos dos fármacos , Absorção Cutânea/fisiologia , Absorção Cutânea/efeitos da radiação
10.
Korean J Urol ; 54(10): 715-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24175048

RESUMO

Urological involvement of hepatocellular carcinoma (HCC) is rare; HCC arising in an orthotopic liver transplant (OLT) is exceptionally rare. Here we report the case of a 70-year-old man who was incidentally found to have metastatic HCC in the right kidney arising from his OLT undertaken for cryptogenic cirrhosis 10 years previously. Adding to the complexity of this case was the lack of an obvious liver primary HCC at the time of the radical nephrectomy, thus making the final diagnosis all but impossible. We believe this report represents the first report of HCC metastasizing to the kidney after OLT and adds to the few reports in the literature of HCC arising in transplanted livers.

11.
Res Rep Urol ; 5: 139-45, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24400245

RESUMO

OBJECTIVES: Our objectives were to analyze the effectiveness of epidural anesthesia in patients who underwent open retropubic radical prostatectomy (RRP) at our institution over the past decade, and to examine subsequent oncologic outcomes, comparing those receiving with those not receiving epidural anesthesia. METHODS: A comprehensive database of all patients undergoing RRP from November 1996 to December 2006 was analyzed; 354 patients underwent RRP at our institution and were divided into those receiving or not receiving an epidural. An independent pain management team scoring technical success found epidural technique to be consistent. Oncological outcome was an endpoint of our study, comparing both analysis groups. We classed prostate-specific antigen (PSA) recurrence after RRP as a serum PSA ≥ 0.2 ng/mL at any stage of postoperative follow-up. Complications were recorded to 30 days using the modified Clavien system, and full statistical analyses were undertaken. RESULTS: Records were available for 239 men; we observed a decreased trend in the use of epidural for pain management, along with a decrease in average hospital stay and an overall epidural success rate of 64%. When dividing data into RRP with and without epidural, we found a median hospital stay of 7 days for patients receiving an epidural compared with 6 days for those not receiving an epidural. The differences were statistically significant (P < 0.048) and remained so after adjusting for complications (P < 0.0001). Regarding oncological outcome, PSA recurrence was further analyzed in this cohort. Percentage of recurrence was higher (14.8%) for patients receiving an epidural than for the non-epidural group (4.8%). The differences were statistically significant (P = 0.012). CONCLUSION: Epidural analgesia increased length of hospital stay and technical problems related to the epidural. Furthermore, men receiving an epidural showed an increased recurrence of PSA. In light of our findings, epidurals are probably not indicated for men undergoing RRP. However, as minimally invasive techniques are becoming more widespread, and epidural analgesia is being used less frequently, large randomized controlled trials to definitively support our hypotheses are unlikely to be undertaken.

12.
Biogerontology ; 11(2): 151-66, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19554469

RESUMO

We investigated acetylcholine esterase (AChE) activity, acetylcholine and muscarinic M1, M3 receptors kinetics in the cerebral cortex of young and old streptozotocin induced and insulin treated diabetic rats. The role of muscarinic receptors in intracellular calcium release from pancreatic islets was studied in vitro. Wistar rats of 7 and 90-weeks old were used. All studies were done in cerebral cortex. AChE assay was done by spectrophotometric method. Radioreceptor binding assays were done for Acetylcholine, Muscarinic M1 and M3 receptors using specific ligands. Calcium imaging was done using fluo4-AM in pancreatic cells. Ninety-weeks old control rats showed significantly decreased Vmax and increased Km for AChE compared to 7-weeks old control rats. An increased Vmax observed in both 7 and 90-weeks old diabetic groups with significant decrease in Km. Scatchard analysis using specific agonists showed significant decrease in the B (max) and K (d) of acetylcholine and muscarinic M1 receptors in 90-weeks old control rats compared to 7-weeks old control. Binding studies for M3 receptors showed no significant change compared to 7-weeks old control. Acetylcholine, muscarinic M1 and M3 receptor number significantly increased in 90-weeks old diabetic rat groups compared to their respective controls. Insulin treatment significantly reversed the binding parameters to near control compared to diabetic group. In vitro studies showed that acetylcholine through muscarinic M1 and M3 receptors' stimulated calcium release from the pancreatic islets. Thus our studies suggest that Insulin signaling play an important part in differentially regulating pancreatic cholinergic activity, and the diabetes mediated cortical dysfunctions with age.


Assuntos
Envelhecimento/fisiologia , Cálcio/metabolismo , Córtex Cerebral/fisiopatologia , Diabetes Mellitus Experimental/fisiopatologia , Ilhotas Pancreáticas/metabolismo , Receptores Colinérgicos/fisiologia , Receptores Muscarínicos/fisiologia , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Modelos Animais de Doenças , Insulina/farmacologia , Insulina/uso terapêutico , Masculino , Ratos , Ratos Wistar , Receptor Muscarínico M1/efeitos dos fármacos , Receptor Muscarínico M1/fisiologia , Receptor Muscarínico M3/efeitos dos fármacos , Receptor Muscarínico M3/fisiologia , Receptores Colinérgicos/efeitos dos fármacos , Receptores Muscarínicos/efeitos dos fármacos , Estreptozocina
13.
Pharmacol Res ; 61(2): 136-41, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19720148

RESUMO

Brain damage due to an episode of hypoxia remains a major problem in infants causing deficit in motor and sensory function. Molecular processes regulating the dopamine receptors play a very important role in motor and cognitive functions. Disturbances in the development of the dopaminergic system lead to dyskinesia, dystonia, tics and abnormal eye movements. The present study is to understand the hypoxic damage to the dopamine content and dopamine D(1), dopamine D(2) receptors in cerebellum and the neuroprotective effect of glucose supplementation prior to the current sequence of resuscitation-oxygen and epinephrine supplementation in neonatal rats. Dopamine content in the cerebellum showed a significant decrease in hypoxic neonatal rats when compared to control. Dopamine D(1) and dopamine D(2) receptors showed a decrease in B(max) during hypoxia. The cerebellar dopamine, dopamine D(1) and dopamine D(2) receptors showed significant decrease on supplementation of 100% oxygen alone to hypoxic rats when compared to control rats. Dopamine D(1) and dopamine D(2) receptors mRNA showed significant decrease during epinephrine supplementation prior to resuscitation. These dopaminergic receptor alterations were reversed to near control by glucose supplementation. Thus our results suggest that glucose acts as a neuroprotective agent in dopaminergic receptors function. This has immense clinical significance to correct the resuscitation sequence in neonatal care.


Assuntos
Cerebelo/efeitos dos fármacos , Epinefrina/administração & dosagem , Glucose/administração & dosagem , Hipóxia Encefálica/terapia , Fármacos Neuroprotetores/administração & dosagem , Oxigenoterapia , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Ressuscitação/métodos , Animais , Animais Recém-Nascidos , Benzamidas/metabolismo , Benzazepinas/metabolismo , Cerebelo/metabolismo , Dopamina/metabolismo , Antagonistas de Dopamina/metabolismo , Regulação para Baixo , Ácido Homovanílico/metabolismo , Hipóxia Encefálica/metabolismo , Reação em Cadeia da Polimerase , Ligação Proteica , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Receptores de Dopamina D1/genética , Receptores de Dopamina D2/genética
14.
J Ethnopharmacol ; 123(3): 470-4, 2009 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-19501280

RESUMO

AIM OF THE STUDY: The leaves of Costus pictus D. Don were used extensively for its antihyperglycemic activity by the people in Kerala, India. In the present study, the antihyperglycemic and insulin secretory activity of an aqueous extract of Costus pictus leaf extract was investigated in streptozotocin induced diabetic rats. MATERIALS AND METHODS: Oral Glucose Tolerance Test was done to determine the effective dose of Costus pictus extract. Aqueous extract of Costus pictus leaves was given orally to the diabetic rats for 14 days. The insulin secretory action of the leaf extract was investigated using isolated pancreatic islets from rat. Liver glucose uptake activity was measured using D-[14C] glucose. RESULTS: The oral administration of an aqueous extract of Costus pictus at a dose of 250 mg/kg body weight significantly decreased the blood glucose with significant increase in plasma insulin level in diabetic rats at the end of 14 days treatment. The Costus pictus leaf extract significantly increased glucose induced insulin secretion at both 4 mM and 20 mM glucose concentrations which represents normal physiological and diabetic condition respectively. The decreased glucose uptake activity of the liver of diabetic rats was reverted to near normal levels after the treatment with Costus pictus leaf extract. CONCLUSION: Our results suggest the glucose lowering effect of Costus pictus to be associated with the potentiation of insulin release from pancreatic islets and enhancement of peripheral utilization of glucose.


Assuntos
Costus , Diabetes Mellitus Experimental/tratamento farmacológico , Glucose/metabolismo , Hipoglicemiantes/uso terapêutico , Insulina/metabolismo , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Peso Corporal/efeitos dos fármacos , Técnicas de Cultura de Células , Teste de Tolerância a Glucose , Hipoglicemiantes/farmacologia , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Masculino , Extratos Vegetais/farmacologia , Folhas de Planta , Plantas Medicinais , Ratos , Ratos Wistar
15.
Neurochem Res ; 33(3): 444-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17721726

RESUMO

In the present study we investigated the role of 5-hydroxytryptamine (5-HT) and 5-HT1A receptor during liver regeneration after partial hepatectomy (PH) and N-nitrosodiethylamine (NDEA) induced hepatocellular carcinoma in male Wistar rats. 5-HT content was significantly increased during liver regeneration after PH and NDEA induced hepatocellular carcinoma. Scatchard analysis using 8-OH-DPAT, a 5-HT1A specific agonist showed a decreased receptor during liver regeneration after PH and NDEA induced hepatocellular carcinoma. 5-HT when added alone to primary hepatocyte culture did not increase DNA synthesis but was able to increase the EGF mediated DNA synthesis and inhibit the TGF beta 1 mediated DNA synthesis suppression in vitro. This confirmed the co-mitogenic activity of 5-HT. 8-OH-DPAT at a concentration of 10(-4) M inhibited the basal and EGF-mediated DNA synthesis in primary hepatocyte cultures. It also suppressed the TGF beta 1-mediated DNA synthesis suppression. This clearly showed that activated 5-HT1A receptor inhibited hepatocyte DNA synthesis. Our results suggest that decreased hepatic 5-HT1A receptor function during hepatocyte regeneration and neoplasia has clinical significance in the control of cell proliferation.


Assuntos
Neoplasias Hepáticas Experimentais/metabolismo , Regeneração Hepática/fisiologia , Receptor 5-HT1A de Serotonina/metabolismo , 8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , Animais , Carcinógenos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Cromatografia Líquida de Alta Pressão , DNA de Neoplasias/biossíntese , DNA de Neoplasias/genética , Dietilnitrosamina , Fator de Crescimento Epidérmico/farmacologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Neoplasias Hepáticas Experimentais/induzido quimicamente , Masculino , Ratos , Ratos Wistar , Serotonina/metabolismo , Agonistas do Receptor de Serotonina/farmacologia , Fator de Crescimento Transformador beta1/farmacologia
16.
J Neurol Sci ; 254(1-2): 3-8, 2007 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-17258772

RESUMO

In the present study, serotonin 2C (5-HT(2C)) receptor binding parameters in the brainstem and cerebral cortex were investigated during liver generation after partial hepatectomy (PH) and N-nitrosodiethylamine (NDEA) induced hepatic neoplasia in male Wistar rats. The serotonin content increased significantly (p<0.01) in the cerebral cortex after PH and in NDEA induced hepatic neoplasia. Brain stem serotonin content increased significantly (p<0.05) after PH and (p<0.001) in NDEA induced hepatic neoplasia. The number and affinity of the 5-HT(2C) receptors in the crude synaptic membrane preparations of the brain stem showed a significant (p<0.001) increase after PH and in NDEA induced hepatic neoplasia. The number and affinity of 5-HT(2C) receptors increased significantly (p<0.001) in NDEA induced hepatic neoplasia in the crude synaptic membrane preparations of the cerebral cortex. There was a significant (p<0.01) increase in plasma norepinephrine in PH and (p<0.001) in NDEA induced hepatic neoplasia, indicating sympathetic stimulation. Thus, our results suggest that during active hepatocyte proliferation 5-HT(2C) receptor in the brain stem and cerebral cortex are up-regulated which in turn induce hepatocyte proliferation mediated through sympathetic stimulation.


Assuntos
Encéfalo/metabolismo , Proliferação de Células , Neoplasias Hepáticas Experimentais/metabolismo , Regeneração Hepática , Fígado/metabolismo , Receptor 5-HT2C de Serotonina/metabolismo , Animais , Ligação Competitiva , Tronco Encefálico/metabolismo , Carcinógenos , Córtex Cerebral/metabolismo , Dietilnitrosamina , Hepatócitos/metabolismo , Fígado/inervação , Neoplasias Hepáticas Experimentais/induzido quimicamente , Masculino , Norepinefrina/metabolismo , Ratos , Ratos Wistar , Serotonina/metabolismo , Fibras Simpáticas Pós-Ganglionares/metabolismo , Membranas Sinápticas/metabolismo , Regulação para Cima
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