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1.
Int J Mol Sci ; 24(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38069231

RESUMO

Autonomic innervation is important to regulate homeostasis in every organ of the body. The sympathetic nervous system controls several organs associated with metabolism and reproduction, including adipose tissue, the liver, and the ovaries. The sympathetic nervous system is controlled within the central nervous system by neurons located in the hypothalamus, which in turn are regulated by hormones like leptin. Leptin action in the hypothalamus leads to increased sympathetic activity in the adipose tissue. In this short report, we propose that leptin action in the brain also controls the sympathetic innervation of other organs like the liver and the ovary. We performed two experiments: We performed an intracerebroventricular (ICV) injection of leptin and measured norepinephrine levels in several organs, and we used a validated model of overnutrition and obesity to evaluate whether an increase in leptin levels coexists with high levels of norepinephrine in the liver and ovaries. Norepinephrine was measured by ELISA in adipose tissue and by HPLC-EC in other tissues. Leptin was measured by ELISA. We found that the ICV injection of leptin increases norepinephrine levels in several organs, including the liver and ovaries. Also, we found that diet-induced obesity leads to an increase in leptin levels while inducing an increase in norepinephrine levels in the liver and ovaries. Finally, since hyperactivity of the sympathetic nervous system is observed both in non-alcoholic fatty liver disease and polycystic ovary syndrome, we think that an increase in norepinephrine levels induced by hyperleptinemia could be involved in the pathogenesis of both diseases.


Assuntos
Leptina , Norepinefrina , Feminino , Tecido Adiposo/metabolismo , Dieta , Leptina/metabolismo , Norepinefrina/metabolismo , Obesidade/metabolismo , Sistema Nervoso Simpático , Animais , Ratos
2.
Int J Mol Sci ; 24(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36674982

RESUMO

Obesity-induced neuroinflammation is a chronic aseptic central nervous system inflammation that presents systemic characteristics associated with increased pro-inflammatory cytokines such as interleukin 1 beta (IL-1ß) and interleukin 18 (IL-18) and the presence of microglia and reactive astrogliosis as well as the activation of the NLRP3 inflammasome. The obesity pandemic is associated with lifestyle changes, including an excessive intake of obesogenic foods and decreased physical activity. Brain areas such as the lateral hypothalamus (LH), lateral septum (LS), ventral tegmental area (VTA), and nucleus accumbens (NAcc) have been implicated in the homeostatic and hedonic control of feeding in experimental models of diet-induced obesity. In this context, a chronic lipid intake triggers neuroinflammation in several brain regions such as the hypothalamus, hippocampus, and amygdala. This review aims to present the background defining the significant impact of neuroinflammation and how this, when induced by an obesogenic diet, can affect feeding control, triggering metabolic and neurological alterations.


Assuntos
Doenças Neuroinflamatórias , Núcleo Accumbens , Humanos , Núcleo Accumbens/metabolismo , Dieta/efeitos adversos , Obesidade/etiologia , Obesidade/metabolismo , Ingestão de Alimentos/fisiologia
3.
Int J Mol Sci ; 24(12)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37373230

RESUMO

Many diseases and degenerative processes affecting the nervous system and peripheral organs trigger the activation of inflammatory cascades. Inflammation can be triggered by different environmental conditions or risk factors, including drug and food addiction, stress, and aging, among others. Several pieces of evidence show that the modern lifestyle and, more recently, the confinement associated with the COVID-19 pandemic have contributed to increasing the incidence of addictive and neuropsychiatric disorders, plus cardiometabolic diseases. Here, we gather evidence on how some of these risk factors are implicated in activating central and peripheral inflammation contributing to some neuropathologies and behaviors associated with poor health. We discuss the current understanding of the cellular and molecular mechanisms involved in the generation of inflammation and how these processes occur in different cells and tissues to promote ill health and diseases. Concomitantly, we discuss how some pathology-associated and addictive behaviors contribute to worsening these inflammation mechanisms, leading to a vicious cycle that promotes disease progression. Finally, we list some drugs targeting inflammation-related pathways that may have beneficial effects on the pathological processes associated with addictive, mental, and cardiometabolic illnesses.


Assuntos
Comportamento Aditivo , COVID-19 , Doenças Cardiovasculares , Doenças do Sistema Nervoso , Humanos , Pandemias , COVID-19/complicações , Envelhecimento/metabolismo , Inflamação/complicações , Doenças do Sistema Nervoso/etiologia
4.
Int J Mol Sci ; 24(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36902133

RESUMO

Obesity is a pandemic caused by many factors, including a chronic excess in hypercaloric and high-palatable food intake. In addition, the global prevalence of obesity has increased in all age categories, such as children, adolescents, and adults. However, at the neurobiological level, how neural circuits regulate the hedonic consumption of food intake and how the reward circuit is modified under hypercaloric diet consumption are still being unraveled. We aimed to determine the molecular and functional changes of dopaminergic and glutamatergic modulation of nucleus accumbens (NAcc) in male rats exposed to chronic consumption of a high-fat diet (HFD). Male Sprague-Dawley rats were fed a chow diet or HFD from postnatal day (PND) 21 to 62, increasing obesity markers. In addition, in HFD rats, the frequency but not amplitude of the spontaneous excitatory postsynaptic current is increased in NAcc medium spiny neurons (MSNs). Moreover, only MSNs expressing dopamine (DA) receptor type 2 (D2) increase the amplitude and glutamate release in response to amphetamine, downregulating the indirect pathway. Furthermore, NAcc gene expression of inflammasome components is increased by chronic exposure to HFD. At the neurochemical level, DOPAC content and tonic dopamine (DA) release are reduced in NAcc, while phasic DA release is increased in HFD-fed rats. In conclusion, our model of childhood and adolescent obesity functionally affects the NAcc, a brain nucleus involved in the hedonic control of feeding, which might trigger addictive-like behaviors for obesogenic foods and, through positive feedback, maintain the obese phenotype.


Assuntos
Dopamina , Obesidade Infantil , Ratos , Masculino , Animais , Dopamina/metabolismo , Núcleo Accumbens/metabolismo , Dieta Hiperlipídica , Ratos Sprague-Dawley , Obesidade Infantil/metabolismo , Transmissão Sináptica/fisiologia , Receptores Dopaminérgicos/metabolismo
5.
Reprod Biol Endocrinol ; 20(1): 30, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35130922

RESUMO

BACKGROUND: Polycystic Ovary Syndrome (PCOS) is an endocrine disorder that affects women in reproductive age and represents an unfavourable risk factor for several pregnancy and perinatal outcomes. Despite, no guidelines or pharmaceutical strategies for treating PCOS during pregnancy are available. The aim of this study is to determine the association between polycystic ovary syndrome with or without metformin and the pregnancy, perinatal outcomes as well as the risk of obesity in children born to these mothers. METHODS: In this nationwide population-based cohort study based in Swedish population, all singleton births (n = 1,016,805) from 686,847 women since 2006 up to 2016 were included. Multivariable logistic and Cox regression modelling with odds ratios (OR) and hazard ratios (HR) and 95% confidence intervals were used to study the association between the exposure of maternal PCOS, metformin during pregnancy (or the combination of both) and: 1) Pregnancy outcomes: preeclampsia, gestational diabetes, caesarean section, and acute caesarean section, 2) Perinatal outcomes: preterm birth, stillbirth, low birth weight, macrosomia, Apgar < 7 at 5 min, small for gestational age and large for gestational age, and 3) Childhood Obesity. RESULTS: PCOS in women without metformin use during pregnancy was associated with higher risks of preeclampsia (OR = 1.09, 1.02-1.17), gestational diabetes (OR = 1.71, 1.53-1.91) and caesarean section (OR = 1.08, 1.04-1.12), preterm birth (OR = 1.30, 1.23-1.38), low birth weight (OR = 1.29, 1.20-1.38), low Apgar scores (OR = 1.17, 1.05-1.31) and large for gestational age (OR = 1.11, 1.03-1.20). Metformin use during pregnancy (in women without PCOS) was associated with a 29% lower risks of preeclampsia (OR = 0.71, 0.51-0.97), macrosomia and large for gestational age. Obesity was more common among children born to mothers with PCOS without metformin (HR = 1.61, 1.44-1.81); and those with metformin without PCOS (HR = 1.67, 1.05-2.65). PCOS with metformin was not associated with any adverse outcome. CONCLUSION: PCOS was associated with increased risks of adverse pregnancy and perinatal outcomes and childhood obesity. Metformin appears to reduce these risks in mothers with polycystic ovary syndrome and their children; but may increase the risk of childhood-obesity in children form women without PCOS.


Assuntos
Metformina/uso terapêutico , Obesidade Infantil/epidemiologia , Síndrome do Ovário Policístico , Resultado da Gravidez/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Diabetes Gestacional/epidemiologia , Feminino , Humanos , Recém-Nascido , Obesidade Infantil/etiologia , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/epidemiologia , Pré-Eclâmpsia/epidemiologia , Gravidez , Complicações na Gravidez/tratamento farmacológico , Complicações na Gravidez/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/etiologia , Prognóstico , Fatores de Risco , Suécia/epidemiologia , Resultado do Tratamento , Adulto Jovem
6.
Int J Mol Sci ; 23(12)2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35743046

RESUMO

The misuse of psychostimulants is an increasing behavior among young people, highlighting in some countries the abuse of modafinil (MOD) as a neuropotentiator. However, several clinical trials are investigating MOD as an alternative pharmacological treatment for attentional deficit and hyperactivity disorder (ADHD) in children and adolescents. On the other hand, the early use of psychostimulants and the misdiagnosis rates in ADHD make it crucial to investigate the brain effects of this type of drug in young healthy individuals. The aim of this work was to evaluate the effects of chronic MOD treatment on neurochemicals (γ-aminobutyric acid and glutamate), dopamine receptor 2 (D2) expression and behavior (non-selective attention "NSA") in the mesocorticolimbic system of young healthy Sprague-Dawley rats. Preadolescent male rats were injected with MOD (75 mg/kg, i.p.) or a vehicle for 14 days (from postnatal day 22 to 35). At postnatal day 36, we measured the GLU and GABA contents and their extracellular levels in the nucleus accumbens (NAc). In addition, the GLU and GABA contents were measured in the ventral tegmental area (VTA) and D2 protein levels in the prefrontal cortex (PFC). Chronic use of MOD during adolescence induces behavioral and neurochemical changes associated with the mesocorticolimbic system, such as a reduction in PFC D2 expression, VTA GABA levels and NSA. These results contribute to the understanding of the neurological effects of chronic MOD use on a young healthy brain.


Assuntos
Estimulantes do Sistema Nervoso Central , Área Tegmentar Ventral , Adolescente , Animais , Atenção , Estimulantes do Sistema Nervoso Central/farmacologia , Ácido Glutâmico/metabolismo , Humanos , Masculino , Modafinila/metabolismo , Modafinila/farmacologia , Núcleo Accumbens/metabolismo , Córtex Pré-Frontal/metabolismo , Ratos , Ratos Sprague-Dawley , Área Tegmentar Ventral/metabolismo , Ácido gama-Aminobutírico/metabolismo
7.
Diabetologia ; 64(6): 1389-1401, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33710396

RESUMO

AIMS/HYPOTHESIS: Skeletal muscle is a key target organ for insulin's actions and is the main regulator of blood glucose. In obese individuals and animal models, there is a chronic low-grade inflammatory state affecting highly metabolic organs, leading to insulin resistance. We have described that adult skeletal muscle fibres can release ATP to the extracellular medium through pannexin-1 (PANX1) channels. Besides, it is known that high extracellular ATP concentrations can act as an inflammatory signal. Here, we propose that skeletal muscle fibres from obese mice release high levels of ATP, through PANX1 channels, promoting inflammation and insulin resistance in muscle cells. METHODS: C57BL/6J mice were fed with normal control diet (NCD) or high-fat diet (HFD) for 8 weeks. Muscle fibres were isolated from flexor digitorum brevis (FDB) muscle. PANX1-knockdown FDB fibres were obtained by in vivo electroporation of a short hairpin RNA Panx1 plasmid. We analysed extracellular ATP levels in a luciferin/luciferase assay. Gene expression was studied with quantitative real-time PCR (qPCR). Protein levels were evaluated by immunoblots, ELISA and immunofluorescence. Insulin sensitivity was analysed in a 2-NBDG (fluorescent glucose analogue) uptake assay, immunoblots and IPGTT. RESULTS: HFD-fed mice showed significant weight gain and insulin resistance compared with NCD-fed mice. IL-6, IL-1ß and TNF-α protein levels were increased in FDB muscle from obese mice. We observed high levels of extracellular ATP in muscle fibres from obese mice (197 ± 55 pmol ATP/µg RNA) compared with controls (32 ± 10 pmol ATP/µg RNA). ATP release in obese mice fibres was reduced by application of 100 µmol/l oleamide (OLE) and 5 µmol/l carbenoxolone (CBX), both PANX1 blockers. mRNA levels of genes linked to inflammation were reduced using OLE, CBX or 2 U/ml ATPase apyrase in muscle fibres from HFD-fed mice. In fibres from mice with pannexin-1 knockdown, we observed diminished extracellular ATP levels (78 ± 10 pmol ATP/µg RNA vs 252 ± 37 pmol ATP/µg RNA in control mice) and a lower expression of inflammatory markers. Moreover, a single pulse of 300 µmol/l ATP to fibres from control mice reduced insulin-mediated 2-NBDG uptake and promoted an elevation in mRNA levels of inflammatory markers. PANX-1 protein levels were increased two- to threefold in skeletal muscle from obese mice compared with control mice. Incubation with CBX increased Akt activation and 2-NBDG uptake in HFD fibres after insulin stimulation, rescuing the insulin resistance condition. Finally, in vivo treatment of HFD-fed mice with CBX (i.p. injection of 10 mg/kg each day) for 14 days, compared with PBS, reduced extracellular ATP levels in skeletal muscle fibres (51 ± 10 pmol ATP/µg RNA vs 222 ± 28 pmol ATP/µg RNA in PBS-treated mice), diminished inflammation and improved glycaemic management. CONCLUSIONS/INTERPRETATION: In this work, we propose a novel mechanism for the development of inflammation and insulin resistance in the skeletal muscle of obese mice. We found that high extracellular ATP levels, released by overexpressed PANX1 channels, lead to an inflammatory state and insulin resistance in skeletal muscle fibres of obese mice.


Assuntos
Trifosfato de Adenosina/metabolismo , Conexinas/metabolismo , Inflamação/metabolismo , Resistência à Insulina/fisiologia , Fibras Musculares Esqueléticas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Obesidade/metabolismo , Animais , Dieta Hiperlipídica/efeitos adversos , Masculino , Camundongos , Camundongos Obesos , Obesidade/etiologia
8.
Int J Mol Sci ; 22(6)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33806797

RESUMO

Among multiple mechanisms, low-grade inflammation is critical for the development of insulin resistance as a feature of type 2 diabetes. The nucleotide-binding oligomerization domain-like receptor family (NOD-like) pyrin domain containing 3 (NLRP3) inflammasome has been linked to the development of insulin resistance in various tissues; however, its role in the development of insulin resistance in the skeletal muscle has not been explored in depth. Currently, there is limited evidence that supports the pathological role of NLRP3 inflammasome activation in glucose handling in the skeletal muscle of obese individuals. Here, we have centered our focus on insulin signaling in skeletal muscle, which is the main site of postprandial glucose disposal in humans. We discuss the current evidence showing that the NLRP3 inflammasome disturbs glucose homeostasis. We also review how NLRP3-associated interleukin and its gasdermin D-mediated efflux could affect insulin-dependent intracellular pathways. Finally, we address pharmacological NLRP3 inhibitors that may have a therapeutical use in obesity-related metabolic alterations.


Assuntos
Inflamassomos/metabolismo , Inflamação/etiologia , Inflamação/metabolismo , Resistência à Insulina , Músculo Esquelético/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Obesidade/etiologia , Obesidade/metabolismo , Animais , Transporte Biológico , Doença Crônica , Glucose/metabolismo , Humanos , Inflamação/tratamento farmacológico , Inflamação/patologia , Interleucina-1beta/metabolismo , Metabolismo dos Lipídeos , Músculo Esquelético/patologia , Obesidade/tratamento farmacológico , Obesidade/patologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
9.
Int J Mol Sci ; 22(9)2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33946994

RESUMO

The gastrointestinal lumen is a rich source of eukaryotic and prokaryotic viruses which, together with bacteria, fungi and other microorganisms comprise the gut microbiota. Pathogenic viruses inhabiting this niche have the potential to induce local as well as systemic complications; among them, the viral ability to disrupt the mucosal barrier is one mechanism associated with the promotion of diarrhea and tissue invasion. This review gathers recent evidence showing the contributing effects of diet, gut microbiota and the enteric nervous system to either support or impair the mucosal barrier in the context of viral attack.


Assuntos
Bacteriófagos/fisiologia , Dieta , Sistema Nervoso Entérico/fisiologia , Mucosa Gástrica/virologia , Microbioma Gastrointestinal , Interações entre Hospedeiro e Microrganismos/fisiologia , Mucosa Intestinal/virologia , Vírus , Defensinas/fisiologia , Digestão , Suscetibilidade a Doenças , Sistema Nervoso Entérico/virologia , Alimentos/virologia , Mucosa Gástrica/imunologia , Mucosa Gástrica/inervação , Mucosa Gástrica/metabolismo , Gastroenterite/virologia , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Mucosa Intestinal/imunologia , Mucosa Intestinal/inervação , Mucosa Intestinal/metabolismo , Desnutrição/virologia , Muco/metabolismo , Muco/virologia , Neurônios/virologia , Infecções Oportunistas/virologia , Vírus de Plantas , Viroses/microbiologia , Viroses/fisiopatologia
10.
Reproduction ; 153(2): R59-R68, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27799628

RESUMO

Successful reproduction is the result of a myriad interactions in which the ovary and the ovarian follicular reserve play a fundamental role. At present, women who delay maternity until after 30 years of age have a decreased fertility rate due to various causes, including damaged follicles and a reduction in the reserve pool of follicles. Therefore, the period just prior to menopause, also known as the subfertile period, is important. The possibility of modulating the follicular pool and the health of follicles during this period to improve fertility is worth exploring. We have developed an animal model to study the ovarian ageing process during this subfertile period to understand the mechanisms responsible for reproductive senescence. In the rat model, we have shown that the sympathetic nervous system participates in regulating the follicular development during ovarian ageing. This article reviews the existing evidence on the presence and functional role of sympathetic nerve activity in regulating the follicular development during ovarian ageing, with a focus on the subfertile period.Free Spanish abstract: A Spanish translation of this abstract is freely available at http://www.reproduction-online.org/content/153/2/R61/suppl/DC1.


Assuntos
Envelhecimento , Fertilidade/fisiologia , Ovário/fisiologia , Reprodução/fisiologia , Animais , Ciclo Estral , Feminino , Humanos , Kisspeptinas/fisiologia , Camundongos , Modelos Animais , Folículo Ovariano/fisiologia , Ovário/inervação , Pré-Menopausa/fisiologia , Ratos , Sistema Nervoso Simpático/fisiologia
12.
Neural Plast ; 2016: 4569785, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26904299

RESUMO

We sought to determine the long-term changes produced by neonatal sex hormone administration on the functioning of midbrain dopaminergic neurons in adult male rats. Sprague-Dawley rats were injected subcutaneously at postnatal day 1 and were assigned to the following experimental groups: TP (testosterone propionate of 1.0 mg/50 µL); DHT (dihydrotestosterone of 1.0 mg/50 µL); EV (estradiol valerate of 0.1 mg/50 µL); and control (sesame oil of 50 µL). At postnatal day 60, neurochemical studies were performed to determine dopamine content in substantia nigra-ventral tegmental area and dopamine release in nucleus accumbens. Molecular (mRNA expression of tyrosine hydroxylase) and cellular (tyrosine hydroxylase immunoreactivity) studies were also performed. We found increased dopamine content in substantia nigra-ventral tegmental area of TP and EV rats, in addition to increased dopamine release in nucleus accumbens. However, neonatal exposure to DHT, a nonaromatizable androgen, did not affect midbrain dopaminergic neurons. Correspondingly, compared to control rats, levels of tyrosine hydroxylase mRNA and protein were significantly increased in TP and EV rats but not in DHT rats, as determined by qPCR and immunohistochemistry, respectively. Our results suggest an estrogenic mechanism involving increased tyrosine hydroxylase expression, either by direct estrogenic action or by aromatization of testosterone to estradiol in substantia nigra-ventral tegmental area.


Assuntos
Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Hormônios Esteroides Gonadais/administração & dosagem , Núcleo Accumbens/efeitos dos fármacos , Substância Negra/efeitos dos fármacos , Tirosina 3-Mono-Oxigenase/metabolismo , Área Tegmentar Ventral/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Di-Hidrotestosterona/administração & dosagem , Neurônios Dopaminérgicos/metabolismo , Estradiol/administração & dosagem , Estradiol/análogos & derivados , Masculino , Núcleo Accumbens/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Substância Negra/metabolismo , Propionato de Testosterona/administração & dosagem , Área Tegmentar Ventral/metabolismo
13.
Rev Biol Trop ; 64(2): 821-36, 2016 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-29451971

RESUMO

The capture blue crab (Callinectes sapidus) is one of the major fisheries of the state of Tamaulipas, Mexico; both in volume and selling price, as well as employment generation, but there is little information on its biological characteristics. The aim of this study was to evaluate the growth parameters of the blue crab, establishing the most appropriate method. We estimated the length frequency of 17 814 crabs from commercial catch of thirteen locations, including four coastal lagoons. The lagoons were El Barril, Madre, Morales and San Andrés from Tamaulipas, State. Growth parameters were evaluated using indirect methods ELEFAN, PROJMAT and SLCA in combination with the jackknife technique to establish the uncertainty of estimates inherent in each method. The growth parameters L∞ and k were consolidated for purposes of comparison with the growth index phi prime (Φ'). With a mode of 110 mm, the interval carapace length varied between 60 and 205 mm. The values of the growth parameters varied according to the method used. Using SLCA, L∞ varied between 259 and 260 mm and k ranged between 0.749 and 0.750 /year; with PROJMAT, L∞ recorded values between 205 and 260 mm, k fluctuated between 0.550 and 0.740/year, and with ELEFAN, L∞ ranged between 156 and 215 mm and k varied between 0.479 and 0.848/year. Estimates by jackknife detected no variability in Φ' between locations and significant differences between methods. The ranges of values of Φ' and PROJMAT estimated SLCA (4.70 to 4.71 and 4.66 to 4.70, respectively) were in the range reported in the literature (4.201-4.798), while lower values ELEFAN contributed significantly (3.87 to 4.27). The SLCA and PROJMAT methods in combination with the jackknife technique, proved to be the most suitable to estimate the growth parameters of C. sapidus.


Assuntos
Decápodes/crescimento & desenvolvimento , Animais , Decápodes/anatomia & histologia , Feminino , Pesqueiros , Masculino , México , Modelos Biológicos , Estações do Ano
14.
Reproduction ; 148(2): 137-45, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24811779

RESUMO

Chronic cold stress applied to adult rats activates ovarian sympathetic innervation and develops polycystic ovary (PCO) phenotype. The PCO syndrome in humans originates during early development and is expressed before or during puberty, which suggests that the condition derived from in utero exposure to neural- or metabolic-derived insults. We studied the effects of maternal sympathetic stress on the ovarian follicular development and on the onset of puberty of female offspring. Timed pregnant rats were exposed to chronic cold stress (4 °C, 3 h/daily from 1000 to 1300 h) during the entire pregnancy. Neonatal rats exposed to sympathetic stress during gestation had a lower number of primary, primordial, and secondary follicles in the ovary and a lower recruitment of primary and secondary follicles derived from the primordial follicular pool. The expression of the FSH receptor and response of the neonatal ovary to FSH were reduced. A decrease in nerve growth factor (NGF) mRNA was found without change in the low-affinity NGF receptor. The FSH-induced development of secondary follicles was decreased. At puberty, estradiol plasma levels decreased without changes in LH plasma levels. Puberty onset (as shown by the vaginal opening) was delayed. Ovarian norepinephrine (NE) was reduced; there was no change in its metabolite, 3-methoxy-4-hydroxyphenylglycol, in stressed rats and no change in NE turnover. The changes in ovarian NE in prepubertal rats stressed during gestation could represent a lower development of sympathetic nerves as a compensatory response to the chronically increased NE levels during gestation and hence participate in delaying reproductive performance in the rat.


Assuntos
Comportamento Materno , Folículo Ovariano/patologia , Puberdade , Maturidade Sexual , Sistema Nervoso Simpático/patologia , Vagina/patologia , Animais , Células Cultivadas , AMP Cíclico/metabolismo , Ensaio de Imunoadsorção Enzimática , Estradiol/sangue , Ciclo Estral/metabolismo , Feminino , Técnicas Imunoenzimáticas , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , Norepinefrina/metabolismo , Folículo Ovariano/metabolismo , Gravidez , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Receptor de Fator de Crescimento Neural/genética , Receptor de Fator de Crescimento Neural/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sistema Nervoso Simpático/metabolismo , Vagina/metabolismo
15.
Int J Biol Macromol ; 266(Pt 2): 131414, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38582481

RESUMO

This research investigated the impact of ohmic heating (OH) on the physicochemical properties and resistant starch formation in native corn starch. Electric field strengths (EFS) of 50, 75, and 100 V/cm were applied to native starch, at a starch-water ratio of 1:1 w/v. The conductivity of the medium is a crucial factor in ohmic heating. In this study, the conductivity values at 120 °C were measured at 1.5 mS/m. The study revealed two distinct outcomes resulting from the application of different EFS. Firstly, a thermal effect induced gelatinization, resulting in a reduction in the enthalpy of corn starch, an increase in the water absorption index (WAI) and the water solubility index (WSI), and a decrease in peak viscosity. Secondly, a non-thermal effect of OH was observed, leading to the electrolysis of certain starch compounds and water. This electrolysis process generated radicals (-OH) that interacted with starch components, augmenting the percentage of resistant starch. This increase was associated with elevated levels of carbonyl and carboxyl groups at 75 and 100 V/cm.


Assuntos
Eletricidade , Solubilidade , Amido , Água , Zea mays , Zea mays/química , Amido/química , Viscosidade , Água/química , Calefação , Fenômenos Químicos , Temperatura Alta , Condutividade Elétrica
16.
Nutrients ; 15(7)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37049561

RESUMO

White adipose tissue (AT) dysfunction plays an important role in the development of cardiometabolic alterations associated with obesity. AT dysfunction is characterized by the loss of the expansion capacity of the AT, an increment in adipocyte hypertrophy, and changes in the secretion profile of adipose cells, associated with accumulation of macrophages and inflammation. Since not all people with an excess of adiposity develop comorbidities, it is necessary to find simple tools that can evidence AT dysfunction and allow the detection of those people with the potential to develop metabolic alterations. This review focuses on the current pathophysiological mechanisms of white AT dysfunction and emerging measurements to assess its functionality.


Assuntos
Tecido Adiposo Branco , Obesidade , Humanos , Obesidade/metabolismo , Tecido Adiposo Branco/metabolismo , Adiposidade , Adipócitos/metabolismo , Inflamação/metabolismo , Tecido Adiposo/metabolismo
17.
Pharmaceuticals (Basel) ; 16(3)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36986469

RESUMO

Kynureninase (KYNU) is a kynurenine pathway (KP) enzyme that produces metabolites with immunomodulatory properties. In recent years, overactivation of KP has been associated with poor prognosis of several types of cancer, in particular by promoting the invasion, metastasis, and chemoresistance of cancer cells. However, the role of KYNU in gliomas remains to be explored. In this study, we used the available data from TCGA, CGGA and GTEx projects to analyze KYNU expression in gliomas and healthy tissue, as well as the potential contribution of KYNU in the tumor immune infiltrate. In addition, immune-related genes were screened with KYNU expression. KYNU expression correlated with the increased malignancy of astrocytic tumors. Survival analysis in primary astrocytomas showed that KYNU expression correlated with poor prognosis. Additionally, KYNU expression correlated positively with several genes related to an immunosuppressive microenvironment and with the characteristic immune tumor infiltrate. These findings indicate that KYNU could be a potential therapeutic target for modulating the tumor microenvironment and enhancing an effective antitumor immune response.

18.
Antioxidants (Basel) ; 12(12)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38136155

RESUMO

Lead (Pb2+) exposure during early life induces cognitive impairment, which was recently associated with an increase in brain kynurenic acid (KYNA), an antagonist of NMDA and alpha-7 nicotinic receptors. It has been described that N-acetylcysteine (NAC) favors an antioxidant environment and inhibits kynurenine aminotransferase II activity (KAT II, the main enzyme of KYNA production), leading to brain KYNA levels decrease and cognitive improvement. This study aimed to investigate whether the NAC modulation of the brain KYNA levels in mice ameliorated Pb2+-induced cognitive impairment. The dams were divided into four groups: Control, Pb2+, NAC, and Pb2++NAC, which were given drinking water or 500 ppm lead acetate in the drinking water ad libitum, from 0 to 23 postnatal days (PNDs). The NAC and Pb2++NAC groups were simultaneously fed NAC (350 mg/day) in their chow from 0 to 23 PNDs. At PND 60, the effect of the treatment with Pb2+ and in combination with NAC on learning and memory performance was evaluated. Immediately after behavioral evaluation, brain tissues were collected to assess the redox environment; KYNA and glutamate levels; and KAT II activity. The NAC treatment prevented the long-term memory deficit exhibited in the Pb2+ group. As expected, Pb2+ group showed redox environment alterations, fluctuations in glutamate levels, and an increase in KYNA levels, which were partially avoided by NAC co-administration. These results confirmed that the excessive KYNA levels induced by Pb2+ were involved in the onset of cognitive impairment and could be successfully prevented by NAC treatment. NAC could be a tool for testing in scenarios in which KYNA levels are associated with the induction of cognitive impairment.

19.
Antioxidants (Basel) ; 11(11)2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36421480

RESUMO

Gestational Diabetes Mellitus (GDM) and preeclampsia (PE) affects 6-25% of pregnancies and are characterized by an imbalance in natural prooxidant/antioxidant mechanisms. Due to their antioxidant and anti-inflammatory properties, polyphenols consumption during the pregnancy might exert positive effects by preventing GDM and PE development. However, this association remains inconclusive. This systematic review and metanalysis is aimed to analyze the association between polyphenol-rich food consumption during pregnancy and the risk of GDM and PE. A systematic search in MEDLINE, EMBASE, and Web of Science (Clarivate Analytics, London, United Kingdom) for articles dated between 1 January 1980 and July 2022 was undertaken to identify randomized controlled trials and observational studies evaluating polyphenol-rich food consumption and the risk of GDM and PE. The Newcastle-Ottawa Scale was used to evaluate the quality of these included studies. Twelve studies were included, of which eight articles evaluated GDM and four studied PE. A total of 3785 women presented with GDM (2.33%). No association between polyphenol consumption and GDM was found (ES = 0.85, 95% CI 0.71-1.01). When total polyphenol intake was considered, a lower likelihood to develop GDM was noted (ES = 0.78, 95% CI 0.69-0.89). Furthermore, polyphenol consumption was not associated with PE development (ES = 0.90, 95% CI 0.57-1.41). In conclusion, for both outcomes, pooled analyses showed no association with polyphenol-rich food consumption during pregnancy. Therefore, association of polyphenol intake with a decreased risk of GDM and PE remains inconclusive.

20.
Artigo em Inglês | MEDLINE | ID: mdl-36083963

RESUMO

Computer vision syndrome causes vision problems and discomfort mainly due to dry eye. Several studies show that dry eye in computer users is caused by a reduction in the blink rate and an increase in the prevalence of incomplete blinks. In this context, this article introduces Eye-LRCN, a new eye blink detection method that also evaluates the completeness of the blink. The method is based on a long-term recurrent convolutional network (LRCN), which combines a convolutional neural network (CNN) for feature extraction with a bidirectional recurrent neural network that performs sequence learning and classifies the blinks. A Siamese architecture is used during CNN training to overcome the high-class imbalance present in blink detection and the limited amount of data available to train blink detection models. The method was evaluated on three different tasks: blink detection, blink completeness detection, and eye state detection. We report superior performance to the state-of-the-art methods in blink detection and blink completeness detection, and remarkable results in eye state detection.

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