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2.
Nature ; 578(7795): 444-448, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31875646

RESUMO

Metformin, the world's most prescribed anti-diabetic drug, is also effective in preventing type 2 diabetes in people at high risk1,2. More than 60% of this effect is attributable to the ability of metformin to lower body weight in a sustained manner3. The molecular mechanisms by which metformin lowers body weight are unknown. Here we show-in two independent randomized controlled clinical trials-that metformin increases circulating levels of the peptide hormone growth/differentiation factor 15 (GDF15), which has been shown to reduce food intake and lower body weight through a brain-stem-restricted receptor. In wild-type mice, oral metformin increased circulating GDF15, with GDF15 expression increasing predominantly in the distal intestine and the kidney. Metformin prevented weight gain in response to a high-fat diet in wild-type mice but not in mice lacking GDF15 or its receptor GDNF family receptor α-like (GFRAL). In obese mice on a high-fat diet, the effects of metformin to reduce body weight were reversed by a GFRAL-antagonist antibody. Metformin had effects on both energy intake and energy expenditure that were dependent on GDF15, but retained its ability to lower circulating glucose levels in the absence of GDF15 activity. In summary, metformin elevates circulating levels of GDF15, which is necessary to obtain its beneficial effects on energy balance and body weight, major contributors to its action as a chemopreventive agent.


Assuntos
Peso Corporal/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Fator 15 de Diferenciação de Crescimento/metabolismo , Metformina/farmacologia , Administração Oral , Adulto , Idoso , Animais , Glicemia/análise , Glicemia/metabolismo , Dieta Hiperlipídica , Método Duplo-Cego , Ingestão de Energia/efeitos dos fármacos , Enterócitos/citologia , Enterócitos/efeitos dos fármacos , Feminino , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/antagonistas & inibidores , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/deficiência , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Fator 15 de Diferenciação de Crescimento/sangue , Fator 15 de Diferenciação de Crescimento/deficiência , Fator 15 de Diferenciação de Crescimento/genética , Homeostase/efeitos dos fármacos , Humanos , Intestinos/citologia , Intestinos/efeitos dos fármacos , Masculino , Metformina/administração & dosagem , Camundongos , Camundongos Obesos , Pessoa de Meia-Idade , Redução de Peso/efeitos dos fármacos
3.
J Med Virol ; 95(2): e28484, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36625386

RESUMO

The apprehension of needles related to injection site pain, risk of transmitting bloodborne pathogens, and effective mass immunization have led to the development of a needle-free injection system (NFIS). Here, we evaluated the efficacy of the NFIS and needle injection system (NIS) for the delivery and immunogenicity of DNA vaccine candidate ZyCoV-D in rhesus macaques against SARS-CoV-2 infection. Briefly, 20 rhesus macaques were divided into 5 groups (4 animals each), that is, I (1 mg dose by NIS), II (2 mg dose by NIS), III (1 mg dose by NFIS), IV (2 mg dose by NFIS) and V (phosphate-buffer saline [PBS]). The macaques were immunized with the vaccine candidates/PBS intradermally on Days 0, 28, and 56. Subsequently, the animals were challenged with live SARS-CoV-2 after 15 weeks of the first immunization. Blood, nasal swab, throat swab, and bronchoalveolar lavage fluid specimens were collected on 0, 1, 3, 5, and 7 days post infection from each animal to determine immune response and viral clearance. Among all the five groups, 2 mg dose by NFIS elicited significant titers of IgG and neutralizing antibody after immunization with enhancement in their titers postvirus challenge. Besides this, it also induced increased lymphocyte proliferation and cytokine response. The minimal viral load post-SARS-CoV-2 challenge and significant immune response in the immunized animals demonstrated the efficiency of NFIS in delivering 2 mg ZyCoV-D vaccine candidate.


Assuntos
COVID-19 , Vacinas de DNA , Vacinas Virais , Animais , SARS-CoV-2 , Macaca mulatta , Anticorpos Neutralizantes , Anticorpos Antivirais , Imunogenicidade da Vacina
4.
Pathophysiology ; 26(2): 103-114, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31130325

RESUMO

Scleroderma is an autoimmune disorder, characterized by morphological changes in skin followed by visceral organs. The pathogenesis of scleroderma involves immune imbalance and generation of auto antibodies. The major causes of scleroderma include multitude of factors such as immune imbalance, oxidative stress, genetics and environment factors. A constant effort has been made to treat scleroderma through different approaches and necessitates life time administration of drugs for maintenance of a good quality life. It has been reported more in women compared to men. Traditional treatment strategies are restricted by limited therapeutic capability due to associated side effects. Advancement in development of novel drug delivery approaches has opened a newer avenue for efficient therapy. Current review is an effort to reflect scleroderma in provisions of its pathogenesis, causative factors, and therapeutic approaches, with concern to mode of action, pharmacokinetics, marketed products, and side effects of drugs.

6.
J Biol Chem ; 291(13): 6664-78, 2016 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-26742848

RESUMO

Perilipins (PLINs) play a key role in energy storage by orchestrating the activity of lipases on the surface of lipid droplets. Failure of this activity results in severe metabolic disease in humans. Unlike all other lipid droplet-associated proteins, PLINs localize almost exclusively to the phospholipid monolayer surrounding the droplet. To understand how they sense and associate with the unique topology of the droplet surface, we studied the localization of human PLINs inSaccharomyces cerevisiae,demonstrating that the targeting mechanism is highly conserved and that 11-mer repeat regions are sufficient for droplet targeting. Mutations designed to disrupt folding of this region into amphipathic helices (AHs) significantly decreased lipid droplet targetingin vivoandin vitro Finally, we demonstrated a substantial increase in the helicity of this region in the presence of detergent micelles, which was prevented by an AH-disrupting missense mutation. We conclude that highly conserved 11-mer repeat regions of PLINs target lipid droplets by folding into AHs on the droplet surface, thus enabling PLINs to regulate the interface between the hydrophobic lipid core and its surrounding hydrophilic environment.


Assuntos
Proteínas de Transporte/química , Gotículas Lipídicas/química , Proteínas de Membrana/química , Fosfoproteínas/química , Saccharomyces cerevisiae/metabolismo , Proteínas de Transporte Vesicular/química , Sequência de Aminoácidos , Animais , Sítios de Ligação , Transporte Biológico , Células COS , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Chlorocebus aethiops , Expressão Gênica , Humanos , Interações Hidrofóbicas e Hidrofílicas , Gotículas Lipídicas/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Micelas , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Perilipina-1 , Perilipina-2 , Perilipina-3 , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Estrutura Secundária de Proteína , Transporte Proteico , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/ultraestrutura , Alinhamento de Sequência , Transgenes , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo
7.
Cell Immunol ; 317: 48-54, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28499490

RESUMO

Whole sporozoite vaccine (WSV) is shown to induce sterile protection that targets Plasmodium liver-stage infection. There are many underlying issues associated with induction of effective sterile protracted protection. In this study, we have addressed how the alterations in successive vaccine regimen could possibly affect the induction of sterile protection. We have demonstrated that the pattern of vaccination with RAS (radiation attenuated sporozoites) induces varying degrees of protection among B6 mice. Animals receiving four successive doses generated 100% sterile protection. However, three successive doses, though with the same parasite inoculum as four doses, could induce sterile protection in ∼50% mice. Interestingly, mice immunized with the same 3 doses, but with longer gap, could not survive the challenge. We demonstrate that degree of protection correlates with the frequencies of IFN-γ+ and multifunctional (IFN-γ+ CD107a+) CD8+ TEM cells present in liver. The failure to achieve protective threshold frequency of these cells in liver might make the host more vulnerable to parasite infection during infectious sporozoite challenge.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Interferon gama/metabolismo , Hepatopatias/imunologia , Fígado/imunologia , Vacinas Antimaláricas/imunologia , Malária/imunologia , Plasmodium/imunologia , Animais , Linfócitos T CD8-Positivos/parasitologia , Células Cultivadas , Interações Hospedeiro-Parasita , Humanos , Memória Imunológica , Fígado/parasitologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Radiação , Esporozoítos/imunologia , Vacinação
8.
Arch Virol ; 162(9): 2705-2713, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28578522

RESUMO

Virotherapy is emerging as an alternative treatment of cancer. Among the candidate oncolytic viruses (OVs), Newcastle disease virus (NDV) has emerged as a promising non-engineered OV. In the present communication, we explored the oncolytic potential of R2B Mukteshwar strain of NDV using SW-620 colon cancer cells. SW-620 cells were xenografted in nude mice and after evaluation of the safety profile, 1 x 107 plaque forming units (PFU) of NDV were inoculated as virotherapeutic agent via the intratumoral (I/T) and intravenous (I/V) route. Tumor growth inhibition was compared with their respective control groups by gross volume and histopathological evaluation. Antibody titer and virus survival were measured by hemagglutination inhibition (HI)/serum neutralization test (SNT) and real-time PCR, respectively. During the safety trial, the test strain did not produce any abnormal symptoms nor weight loss in BALB/c mice. Significant tumor lytic activity was evident when viruses were injected via the I/T route. There was a 43 and 57% tumor growth inhibition on absolute and relative tumor volume basis, respectively, compared with mock control. On the same basis, the I/V route treatment resulted in 40 and 16% of inhibition, respectively. Histopathological examination revealed that the virus caused apoptosis, followed by necrosis, but immune cell infiltration was not remarkable. The virus survived in 2/2 mice until day 10 and in 3/6 mice by day 19, with both routes of administration. Anti-NDV antibodies were generated at moderate level and the titer reached a maximum of 1:32 and 1:64 via the I/T and I/V routes, respectively. In conclusion, the test NDV strain was found to be safe and showed oncolytic activity against the SW-620 cell line in mice.


Assuntos
Neoplasias do Colo/terapia , Neoplasias Experimentais/terapia , Vírus da Doença de Newcastle/classificação , Terapia Viral Oncolítica , Vírus Oncolíticos , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus
9.
Nature ; 480(7376): E4-5; discussion E6, 2011 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-22158250

RESUMO

Arising from C. J. Phiel, C. A. Wilson, V. M.-Y. Lee & P. S. Klein 423, 435-439 (2003)A major unresolved issue in Alzheimer's disease is identifying the mechanisms that regulate proteolytic processing of amyloid precursor protein (APP)-glycogen synthase kinase-3 (GSK-3) isozymes are thought to be important in this regulation. Phiel et al. proposed that GSK-3α, but not GSK-3ß, controls production of amyloid. We analysed the proteolytic processing of mouse and human APP in mouse brain in vivo in five different genetic and viral models. Our data do not yield evidence for either GSK-3α-mediated or GSK-3ß-mediated control of APP processing in brain in vivo.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Animais
10.
Proc Natl Acad Sci U S A ; 111(25): 9163-8, 2014 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-24927580

RESUMO

Lipid droplets (LDs) are a conserved feature of most organisms. Vertebrate adipocytes have evolved to efficiently store and release lipids for the whole organism from a single droplet. Perilipin 1, the most abundant lipid-coat protein in adipocytes, plays a key role in regulating lipolysis. In other tissues such as liver and muscle, LDs serve very different biological functions, buffering surplus lipids for subsequent oxidation or export. These tissues express perilipins 2 or 3, rather than perilipin 1. We sought to understand the role of perilipins 2 and 3 in regulating basal lipolysis. Bimolecular fluorescence complementation studies suggested that whereas perilipin 1 prevents the activation of adipose tissue triacylglycerol lipase by its coactivator, AB-hydrolase domain containing-5 (ABHD5), perilipins 2 and 3 do so less effectively. These differences are mediated by a conserved region within the carboxy terminus of perilipin 1 that binds and stabilizes ABHD5 by retarding its degradation by the proteosome. Chimeric proteins generated by fusing the carboxy terminus of perilipin 1 to the amino terminus of perilipins 2 or 3 stabilize ABHD5 and suppress basal lipolysis more effectively than WT perilipins 2 or 3. Furthermore, knockdown of perilipin 1 in adipocytes leads to replacement of perilipin 2 on LDs. In these cells we observed reduced ABHD5 expression and LD localization and a corresponding increase in basal lipolysis. Collectively these data suggest that whereas perilipin 1 potently suppresses basal lipolysis in adipocytes, perilipins 2 and 3 facilitate higher rates of basal lipolysis in other tissues where constitutive traffic of fatty acids via LDs is a necessary step in their metabolism.


Assuntos
1-Acilglicerol-3-Fosfato O-Aciltransferase/metabolismo , Adipócitos/metabolismo , Proteínas de Transporte/metabolismo , Lipólise/fisiologia , Proteínas de Membrana/metabolismo , Fosfoproteínas/metabolismo , 1-Acilglicerol-3-Fosfato O-Aciltransferase/genética , Células 3T3-L1 , Adipócitos/citologia , Animais , Proteínas de Transporte/genética , Proteínas de Membrana/genética , Camundongos , Perilipina-1 , Perilipina-2 , Perilipina-3 , Fosfoproteínas/genética , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Estrutura Terciária de Proteína , Proteólise
11.
Daru ; 22(1): 7, 2014 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-24393240

RESUMO

BACKGROUND: Alopecia is a dermatological disorder with psychosocial implications on patients with hair loss. Hair loss is one of the most feared side effects of chemotherapy. Plants have been widely used for hair growth promotion since ancient times in Ayurveda, Chinese and Unani systems of medicine. The effect of extracts of Cuscuta reflexa Roxb. in testosterone induced alopecia was reported. OBJECTIVE: In the present study, the efficacies of the extracts of Cuscuta reflexa in promoting hair growth in cyclophosphamide-induced hair loss have been determined. MATERIALS AND METHODS: The study was performed by treated with petroleum ether and ethanolic extract of Cuscuta reflexa at the dose 250 mg/kg in male swiss albino rats. Cyclophosphamide (125 mg/kg) was used to induce alopecia. RESULTS: Groups treated with extracts of plant showed hair regrowth. Histopathology and gross morphologic observations for hair regrowth at shaved sites revealed active follicular proliferation. CONCLUSIONS: It concluded that extracts of Cuscuta reflexa shown to be capable of promoting follicular proliferation or preventing hair loss in cyclophosphamide-induced hair fall.

12.
Cureus ; 16(2): e54087, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38487134

RESUMO

This case report explores the feasibility and efficacy of endoscopic retrograde appendicitis therapy (ERAT) in treating a 42-year-old female with subacute appendicitis complicated by an abscess. The patient, initially presenting with abdominal pain, underwent an endoscopic intervention involving drainage, irrigation, and stent placement in the appendix. The study discusses the patient's successful outcome, emphasizing the role of ERAT in managing complicated appendicitis with abscesses. The report outlines the case presentation with the initial misdiagnosis of cecal intussusception. The endoscopic procedure involved identifying a partially prolapsed appendix, spontaneous drainage of purulent discharge, and subsequent stent placement to facilitate drainage while awaiting definitive surgery. The patient's positive response to ERAT was marked by pain reduction and a follow-up CT scan confirming the absence of an abscess and a normal appendix. The case report asserts that ERAT emerges as a promising alternative to immediate appendectomy for patients with subacute appendicitis complicated by abscesses, enhancing symptom relief and reducing major adverse events.

13.
Lab Anim Res ; 40(1): 7, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409070

RESUMO

BACKGROUND: Wistar rats are extensively used as the model for assessing toxicity and efficacy in preclinical research. Hematological and biochemical laboratory data are essential for evaluating specific variations in the physiological and functional profile of a laboratory animal. Establishing hematological and biochemical reference values for Wistar (han) rats at various age intervals was the goal of this work. Male and female Wistar rats (n = 660) of ages 6-8 weeks, 10-14 weeks and > 6 months were used in the experiment. Blood and serum were collected from these rats under fasting conditions. RESULTS: We observed that the majority of hematological and biochemical parameters were significantly influenced by sex and age. Hematological changes were significantly correlated to aging were increased red blood cells, hemoglobin, hematocrit, neutrophils, monocytes and eosinophils in both sexes, as well as decreased platelet, mean corpuscular volume, mean corpuscular hemoglobin and lymphocytes in both sexes. White blood cells of male rats were considerably higher than those of female rats in all age ranges. For biochemistry, increase in glucose, total protein and creatinine were seen in both sexes, along with increases in urea in females and alanine aminotransferase in males. Age was significantly associated with decreased alkaline phosphatase in both sexes. CONCLUSIONS: When using Wistar rats as a model, these reference values may be useful in evaluating the results.

14.
Sci Rep ; 14(1): 1899, 2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253650

RESUMO

The hormone GDF15 is secreted in response to cellular stressors. Metformin elevates circulating levels of GDF15, an action important for the drug's beneficial effects on body weight. Metformin can also inhibit mammalian respiratory complex I, leading to decreases in ATP:AMP ratio, activation of AMP Kinase (AMPK), and increased GDF15 production. We undertook studies using a range of mice with tissue-specific loss of Gdf15 (namely gut, liver and global deletion) to determine the relative contributions of two classical metformin target tissues, the gut and liver, to the elevation of GDF15 seen with metformin. In addition, we performed comparative studies with another pharmacological agent, the AMP kinase pan-activator, MK-8722. Deletion of Gdf15 from the intestinal epithelium significantly reduced the circulating GDF15 response to oral metformin, whereas deletion of Gdf15 from the liver had no effect. In contrast, deletion of Gdf15 from the liver, but not the gut, markedly reduced circulating GDF15 responses to MK-8722. Further, our data show that, while GDF15 restricts high-fat diet-induced weight gain, the intestinal production of GDF15 is not necessary for this effect. These findings add to the body of evidence implicating the intestinal epithelium in key aspects of the pharmacology of metformin action.


Assuntos
Fator 15 de Diferenciação de Crescimento , Metformina , Animais , Camundongos , Adenilato Quinase/metabolismo , Transporte Biológico , Mucosa Intestinal , Fígado , Mamíferos , Metformina/farmacologia , Fator 15 de Diferenciação de Crescimento/metabolismo
15.
Elife ; 122023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36722855

RESUMO

Mitochondrial dysfunction has been reported in obesity and insulin resistance, but primary genetic mitochondrial dysfunction is generally not associated with these, arguing against a straightforward causal relationship. A rare exception, recently identified in humans, is a syndrome of lower body adipose loss, leptin-deficient severe upper body adipose overgrowth, and insulin resistance caused by the p.Arg707Trp mutation in MFN2, encoding mitofusin 2. How the resulting selective form of mitochondrial dysfunction leads to tissue- and adipose depot-specific growth abnormalities and systemic biochemical perturbation is unknown. To address this, Mfn2R707W/R707W knock-in mice were generated and phenotyped on chow and high fat diets. Electron microscopy revealed adipose-specific mitochondrial morphological abnormalities. Oxidative phosphorylation measured in isolated mitochondria was unperturbed, but the cellular integrated stress response was activated in adipose tissue. Fat mass and distribution, body weight, and systemic glucose and lipid metabolism were unchanged, however serum leptin and adiponectin concentrations, and their secretion from adipose explants were reduced. Pharmacological induction of the integrated stress response in wild-type adipocytes also reduced secretion of leptin and adiponectin, suggesting an explanation for the in vivo findings. These data suggest that the p.Arg707Trp MFN2 mutation selectively perturbs mitochondrial morphology and activates the integrated stress response in adipose tissue. In mice, this does not disrupt most adipocyte functions or systemic metabolism, whereas in humans it is associated with pathological adipose remodelling and metabolic disease. In both species, disproportionate effects on leptin secretion may relate to cell autonomous induction of the integrated stress response.


Assuntos
Resistência à Insulina , Lipodistrofia , Humanos , Animais , Camundongos , Leptina/metabolismo , Adiponectina/metabolismo , Tecido Adiposo/metabolismo , Obesidade/metabolismo , Hidrolases/metabolismo , Lipodistrofia/genética , Lipodistrofia/metabolismo , Mitocôndrias/metabolismo
16.
Cell Metab ; 6(4): 329-37, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17908561

RESUMO

Glycogen synthase kinase 3 comprises two isoforms (GSK-3alpha and GSK-3beta) that are implicated in type II diabetes, neurodegeneration, and cancer. GSK-3 activity is elevated in human and rodent models of diabetes, and various GSK-3 inhibitors improve glucose tolerance and insulin sensitivity in rodent models of obesity and diabetes. Here, we report the generation of mice lacking GSK-3alpha. Unlike GSK-3beta mutants, which die before birth, GSK-3alpha knockout (GSK-3alpha KO) animals are viable but display enhanced glucose and insulin sensitivity accompanied by reduced fat mass. Fasted and glucose-stimulated hepatic glycogen content was enhanced in GSK-3alpha KO mice, whereas muscle glycogen was unaltered. Insulin-stimulated protein kinase B (PKB/Akt) and GSK-3beta phosphorylation was higher in GSK-3alpha KO livers compared to wild-type littermates, and IRS-1 expression was markedly increased. We conclude that GSK-3 isoforms exhibit tissue-specific physiological functions and that GSK-3alpha KO mice are insulin sensitive, reinforcing the potential of GSK-3 as a therapeutic target for type II diabetes.


Assuntos
Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Hepático/metabolismo , Fígado/enzimologia , Animais , Glucose/farmacologia , Quinase 3 da Glicogênio Sintase/genética , Insulina/farmacologia , Isoenzimas/genética , Isoenzimas/metabolismo , Glicogênio Hepático/análise , Camundongos , Camundongos Knockout , Proteínas Proto-Oncogênicas c-akt/metabolismo
17.
Dev Cell ; 12(6): 957-71, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17543867

RESUMO

In mammalian cells, glycogen synthase kinase-3 (GSK-3) exists as two homologs, GSK-3alpha and GSK-3beta, encoded by independent genes, which share similar kinase domains but differ substantially in their termini. Here, we describe the generation of an allelic series of mouse embryonic stem cell (ESC) lines with 0-4 functional GSK-3 alleles and examine GSK-3-isoform function in Wnt/beta-catenin signaling. No compensatory upregulation in GSK-3 protein levels or activity was detected in cells lacking either GSK-3alpha or GSK-3beta, and Wnt/beta-catenin signaling was normal. Only in cells lacking three or all four of the alleles was a gene-dosage effect on beta-catenin/TCF-mediated transcription observed. Indeed, GSK-3alpha/beta double-knockout ESCs displayed hyperactivated Wnt/beta-catenin signaling and were severely compromised in their ability to differentiate, but could be rescued to normality by re-expression of functional GSK-3. The rheostatic regulation of GSK-3 highlights the importance of considering the contributions of both homologs when studying GSK-3 functions in mammalian systems.


Assuntos
Embrião de Mamíferos/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animais , Linhagem Celular , Citosol/metabolismo , Embrião de Mamíferos/citologia , Imunofluorescência , Quinase 3 da Glicogênio Sintase/genética , Glicogênio Sintase Quinase 3 beta , Proteínas de Fluorescência Verde/metabolismo , Camundongos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Células-Tronco/metabolismo , Proteínas Wnt/genética , beta Catenina/genética
18.
Circ Res ; 106(10): 1635-45, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20360256

RESUMO

RATIONALE: Numerous studies have proposed that glycogen synthase kinase (GSK)-3beta is a central regulator of the hypertrophic response of cardiomyocytes. However, all of this work has relied on overexpression of GSK-3beta, expression of constitutively active mutants, or small molecule inhibitors with documented off-target effects. Genetic loss of function approaches have not been used in the adult mouse because germ-line deletion of GSK-3beta is embryonic-lethal. OBJECTIVE: This study was designed to define the role played by GSK-3beta in pressure overload (PO)-induced hypertrophy and remodeling following myocardial infarction (MI). METHODS AND RESULTS: We used a mouse model that allows inducible, cardiomyocyte-specific deletion of GSK-3beta in the adult knockout. Surprisingly, we find that knockout mice exposed to PO induced by thoracic aortic constriction exhibit a normal hypertrophic response. Thus, in contrast to virtually all prior published studies, GSK-3beta appears to play at most a minor role in the hypertrophic response to PO stress. However, GSK-3beta does regulate post-MI remodeling because the GSK-3beta knockouts had less left ventricular dilatation and better-preserved left ventricular function at up to 8 weeks post-MI despite demonstrating significantly more hypertrophy in the remote myocardium. Deletion of GSK-3beta also led to increased cardiomyocyte proliferation following PO and MI. CONCLUSIONS: Deletion of GSK-3beta protects against post-MI remodeling and promotes stress-induced cardiomyocyte proliferation in the adult heart. These studies suggest that inhibition of GSK-3beta could be a strategy to both prevent remodeling and to promote cardiac regeneration in pathological states.


Assuntos
Quinase 3 da Glicogênio Sintase/metabolismo , Infarto do Miocárdio/patologia , Miócitos Cardíacos/citologia , Remodelação Ventricular/fisiologia , Animais , Aorta Torácica/patologia , Cardiomegalia/patologia , Divisão Celular , Éxons , Deleção de Genes , Quinase 3 da Glicogênio Sintase/deficiência , Quinase 3 da Glicogênio Sintase/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos Cardíacos/patologia , Cadeias Pesadas de Miosina/genética , Regiões Promotoras Genéticas , Vasoconstrição
19.
Zhong Xi Yi Jie He Xue Bao ; 10(3): 249-55, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22409913

RESUMO

Cuscuta reflexa Roxb. is a golden yellow, leafless, perennial, parasitic herb of the family Convolvulaceae. C. reflexa has been investigated for antispasmodic, hemodynamic, anticonvulsant, anti steroidogenic, antihypertensive, muscle relaxant, cardiotonic, antiviral, antibacterial, antioxidant, cholinergic, diuretic and hair growth activities. Many chemical constituents have been isolated from C. reflexa such as cuscutin, amarbelin, ß-sitosterol, stigmasterol, kaempferol, dulcitol, myricetin, quercetin, coumarin and oleanolic acid. This review presents a detailed survey of the literature on pharmacognosy, phytochemistry and traditional and biological medicinal uses of C. reflexa.


Assuntos
Cuscuta/química , Extratos Vegetais/farmacologia , Medicamentos de Ervas Chinesas/farmacologia
20.
Lab Anim Res ; 38(1): 33, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36369051

RESUMO

BACKGROUND: Nonhuman primates are used for research purposes such as studying diseases and drug discovery and development programs. Various clinical pathology parameters are used as biomarkers of disease conditions in biomedical research. Detailed reports of these parameters are not available for Indian-origin rhesus macaques. To meet the increasing need for information, we conducted this study on 121 adult Indian rhesus macaques (57 wild-sourced and 64 inhouse animals, aged 3-7 years). A total of 18 hematology and 18 biochemistry parameters were evaluated and reported in this study. Data from these parameters were statistically evaluated for significance amongst inhouse and wild-born animals and for differences amongst sexes. The reference range was calculated according to C28-A3 guidelines for reporting reference intervals of clinical laboratory parameters. RESULTS: Source of the animals and sex appeared to have statistically significant effects on reference values and range. Wild-born animals reported higher WBC, platelets, neutrophils, RBC, hemoglobin, HCT, MCV, and total protein values in comparison to inhouse monkeys. Sex-based differences were observed for parameters such as RBCs, hemoglobin, HCT, creatinine, calcium, phosphorus, albumin, and total protein amongst others. CONCLUSIONS: Through this study, we have established a comprehensive data set of reference values and intervals for certain hematological and biochemical parameters which will help researchers in planning, conducting, and interpreting various aspects of biomedical research employing Indian-origin rhesus monkeys.

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