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Lines of evidence have shown the embryogenic and transgenerational impact of bisphenol A (BPA), an endocrine-disrupting chemical, on immune-metabolic alterations, inflammation, and oxidative stress, while BPA toxic effects in adult obese mice are still overlooked. Here, we evaluate BPA's worsening effect on several hepatic maladaptive processes associated to high-fat diet (HFD)-induced obesity in mice. After 12 weeks HFD feeding, C57Bl/6J male mice were exposed daily to BPA (50 µg/kg per os) along with HFD for 3 weeks. Glucose tolerance and lipid metabolism were examined in serum and/or liver. Hepatic oxidative damage (reactive oxygen species, malondialdehyde, antioxidant enzymes), and mitochondrial respiratory capacity were evaluated. Moreover, liver damage progression and inflammatory/immune response were determined by histological and molecular analysis. BPA amplified HFD-induced alteration of key factors involved in glucose and lipid metabolism, liver triglycerides accumulation, and worsened mitochondrial dysfunction by increasing oxidative stress and reducing antioxidant defense. The exacerbation by BPA of hepatic immune-metabolic dysfunction induced by HFD was shown by increased toll-like receptor-4 and its downstream pathways (i.e., NF-kB and NLRP3 inflammasome) amplifying inflammatory cytokine transcription and promoting fibrosis progression. This study evidences that BPA exposure represents an additional risk factor for the progression of fatty liver diseases strictly related to the cross-talk between oxidative stress and immune-metabolic impairment due to obesity.
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Fatty acid ethanolamides acting on proliferator-activated receptor (PPAR)-α are among the endogenous lipid molecules that attenuate inflammatory processes and pain sensitivity. Whereas these properties are well-known for palmitoylethanolamide (PEA), the efficacy of oleoylethanolamide (OEA, first described as a satiety hormone synthesized in the jejunum) has been overlooked. In this study, we aimed to evaluate the effect of OEA administration in a mouse model of colitis. C57BL/6J mice were exposed to 2.5% dextran sodium sulphate (DSS) in drinking water for 5 days. Daily i.p. administration of 10 mg/kg OEA started 3 days before DSS and lasted for 12 days. The DSS-untreated control group received only ultrapure water. DSS mice treated with OEA had a significant improvement of disease score. OEA restored mRNA transcription of PPAR-α, of tight junctions and protective factors of colon integrity disrupted by DSS. The improvement correlated with significant decrease of colonic and systemic levels of pro-inflammatory cytokines compared to the DSS group. OEA antiinflammatory effects were mediated by the selective targeting of the TLR4 axis causing a downstream inhibition of nuclear factor kappa B (NF-κB)- MyD88-dependent and NLRP3 inflammation pathways. OEA treatment also inhibited DSS-induced increase of inflammatory cytokines levels in the mesenteric lymph nodes. CONCLUSIONS AND IMPLICATIONS: These results underscore the validity of OEA as a potent protective and anti-inflammatory agent in ulcerative colitis that may be exploited to broaden the pharmacological strategies against inflammatory bowel disease.
Assuntos
Anti-Inflamatórios/farmacologia , Colite/prevenção & controle , Colo/efeitos dos fármacos , Sulfato de Dextrana , Endocanabinoides/farmacologia , Fatores Imunológicos/farmacologia , Ácidos Oleicos/farmacologia , Animais , Colite/induzido quimicamente , Colite/imunologia , Colite/metabolismo , Colo/imunologia , Colo/metabolismo , Colo/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Mediadores da Inflamação/metabolismo , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Linfonodos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , Permeabilidade , Transdução de Sinais , Receptor 4 Toll-Like/metabolismoRESUMO
Ulcerative dermatitis (UD) is an idiopathic, spontaneous and progressive disease typically affecting C57BL/6 aged mice with an unknown aetiopathogenesis. For this study, we evaluated 25 cases of UD in C57BL/6NCrl-Tg(HMGA1P6)1Pg mice. Formalin-fixed, paraffin-embedded skin samples were submitted to morphological investigations. Immunohistochemical analysis was performed to characterize and quantify inflammatory cells using CD3, CD45/B220, CD4, CD8 and IL-17 antibodies. Mast cell-bound IgE was investigated by immunofluorescence, whereas serum and cryopreserved skin samples were collected for molecular analysis. Student's t-test (two-tailed) was performed to assess significant differences between the two groups. Affected skin showed extensive areas of ulceration and diffuse, severe and mixed inflammatory infiltrates. No relevant changes were observed in control mice. Immunohistochemical analysis showed a predominant CD3 + CD4 + leukocyte population with fewer CD45/B220 and IL-17 immunolabelled cells and mast cell-bound IgE. Increases in TNFα, IL-1ß and Il-6 mRNA expression were observed in the skin of affected animals compared to controls. Serum TNFα and IL-6 did not vary between affected and control mice. Inflammatory infiltrates and cytokine expression were consistent with both Th2/IgE and Th17 differentiation, a typical pattern of a type I hypersensitivity reaction. Overall, our data suggest an allergic-based aetiopathogenesis of UD in C57BL/6NCrl-Tg(HMGA1P6)1Pg mice.
Assuntos
Dermatite/imunologia , Úlcera Cutânea/imunologia , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Horses affected by chronic piroplasmosis may develop poor performance and muscle atrophy. Here we investigate the pathological and immunopathological aspects of myopathy occurring in chronic equine piroplasmosis. The study included 16 horses serologically positive for equine piroplasms presenting with clinical signs and supporting serum biochemical evidence of a myopathy. Skeletal muscle was evaluated by histopathology, immunohistochemistry, indirect immunofluorescence, and molecular detection of piroplasms and inflammatory cytokines in skeletal muscle. Histologic lesions included muscle fiber atrophy (100% of cases), degenerative changes (13/16, 81%), and perivascular perimysial and endomysial lymphocytic infiltrates (81% of cases). In 15 cases (94%), muscle fibers had strong immunostaining for major histocompatibility complex classes I and II. T lymphocyte populations were mainly CD3+, CD8+, and CD4+ in equal proportions, with a lower number of CD79α+ cells. The serum from affected horses was tested by indirect immunofluorescence for binding of IgG, IgM, or IgA to sections of normal equine muscle to detect circulating autoantibodies against muscle antigen(s). In all cases, distinct sarcolemmal staining was detected in sections incubated with serum from affected horses, in contrast to sections incubated with phosphate-buffered saline or equine control sera. Reverse transcription polymerase chain reaction (RT-PCR) testing of muscles from affected animals revealed a significant increase of interferon-γ, interleukin-12, and tumor necrosis factor-α gene expression compared to healthy controls. Theileria equi or Babesia caballi was not detected in samples of affected muscle by RT-PCR. Thus, inflammatory myopathy associated with equine piroplasmosis may involve an autoimmune pathogenesis with upregulation of inflammatory cytokines that may cause myofiber atrophy and degeneration.
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Babesiose/patologia , Doenças dos Cavalos/patologia , Miosite/veterinária , Animais , Babesiose/complicações , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Doenças dos Cavalos/parasitologia , Cavalos , Masculino , Músculo Esquelético/parasitologia , Músculo Esquelético/patologia , Miosite/etiologia , Miosite/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterináriaRESUMO
The human gut is a composite anaerobic environment with a large, diverse and dynamic enteric microbiota, represented by more than 100 trillion microorganisms, including at least 1000 distinct species. The discovery that a different microbial composition can influence behavior and cognition, and in turn the nervous system can indirectly influence enteric microbiota composition, has significantly contributed to establish the well-accepted concept of gut-brain axis. This hypothesis is supported by several evidence showing mutual mechanisms, which involve the vague nerve, the immune system, the hypothalamic-pituitaryadrenal (HPA) axis modulation and the bacteria-derived metabolites. Many studies have focused on delineating a role for this axis in health and disease, ranging from stress-related disorders such as depression, anxiety and irritable bowel syndrome (IBS) to neurodevelopmental disorders, such as autism, and to neurodegenerative diseases, such as Parkinson Disease, Alzheimer's Disease etc. Based on this background, and considering the relevance of alteration of the symbiotic state between host and microbiota, this review focuses on the role and the involvement of bioactive lipids, such as the N-acylethanolamine (NAE) family whose main members are N-arachidonoylethanolamine (AEA), palmitoylethanolamide (PEA) and oleoilethanolamide (OEA), and short chain fatty acids (SCFAs), such as butyrate, belonging to a large group of bioactive lipids able to modulate peripheral and central pathologic processes. Their effective role has been studied in inflammation, acute and chronic pain, obesity and central nervous system diseases. A possible correlation has been shown between these lipids and gut microbiota through different mechanisms. Indeed, systemic administration of specific bacteria can reduce abdominal pain through the involvement of cannabinoid receptor 1 in the rat; on the other hand, PEA reduces inflammation markers in a murine model of inflammatory bowel disease (IBD), and butyrate, producted by gut microbiota, is effective in reducing inflammation and pain in irritable bowel syndrome and IBD animal models. In this review, we underline the relationship among inflammation, pain, microbiota and the different lipids, focusing on a possible involvement of NAEs and SCFAs in the gut-brain axis and their role in the central nervous system diseases.
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Doenças do Sistema Nervoso Central/fisiopatologia , Inflamação/fisiopatologia , Lipídeos/fisiologia , Dor/fisiopatologia , Animais , Doenças do Sistema Nervoso Central/tratamento farmacológico , Doenças do Sistema Nervoso Central/metabolismo , Disbiose/tratamento farmacológico , Disbiose/metabolismo , Disbiose/fisiopatologia , Endocanabinoides/metabolismo , Endocanabinoides/fisiologia , Etanolaminas/metabolismo , Ácidos Graxos Voláteis/metabolismo , Ácidos Graxos Voláteis/fisiologia , Ácidos Graxos Voláteis/uso terapêutico , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/fisiologia , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Enteropatias/tratamento farmacológico , Enteropatias/metabolismo , Enteropatias/fisiopatologia , Lipídeos/uso terapêutico , Dor/tratamento farmacológico , Dor/metabolismoRESUMO
Ursodeoxycholic acid (UDCA) is considered the first-choice therapy for cholestatic disorders. To enhance solubility and exploit specific transporters in liver, we synthesized a new galactosyl pro-drug of UDCA (UDCAgal). Ethinylestradiol (EE)-induced cholestasis was used to study and compare the effects of UDCAgal with UDCA on bile flow, hepatic canalicular efflux transporter expression, and inflammation. UDCAgal resulted quite stable both at pH 7.4 and 1.2 and regenerated the parent drug after incubation in human plasma. Its solubility, higher than UDCA, was pH- and temperature-independent. UDCAgal displayed a higher cell permeation compared to UDCA in liver HepG2 cells. Moreover, in cholestatic rats, UDCAgal showed a higher potency compared to UDCA in reducing serum biomarkers (AST, ALT, and ALP) and cytokines (TNF-α and IL-1ß). The higher effect of UDCAgal on the increase in bile salt export pump and multidrug resistance-associated protein 2 transcription indicated an improved spillover of bile acids from the liver. UDCAgal showed a reduction in CCL2, as well as TNF-α, IL-1ß, and cyclooxygeanse-2 mRNAs, indicating a reduction in hepatic neutrophil accumulation and inflammation. Moreover, UDCAgal, similarly to UDCA, heightens bile flow and modulates biliary acids secretion. These results indicate that UDCAgal has a potential in the treatment of cholestatic disease.
Assuntos
Colestase/tratamento farmacológico , Estrogênios/toxicidade , Ácido Ursodesoxicólico/química , Ácido Ursodesoxicólico/uso terapêutico , Animais , Colestase/metabolismo , Ciclo-Oxigenase 2/sangue , Etinilestradiol/toxicidade , Células Hep G2 , Humanos , Interleucina-1beta/sangue , Masculino , Proteína 2 Associada à Farmacorresistência Múltipla , Proteínas Associadas à Resistência a Múltiplos Medicamentos/sangue , Pró-Fármacos/síntese química , Pró-Fármacos/química , Pró-Fármacos/uso terapêutico , Ratos , Ratos Wistar , Solubilidade , Fator de Necrose Tumoral alfa/sangue , Ácido Ursodesoxicólico/síntese químicaRESUMO
The potential mechanisms of action of polyphenols in nonalcoholic fatty liver disease (NAFLD) are overlooked. Here, we evaluate the beneficial therapeutic effects of hydroxytyrosol (HT), the major metabolite of the oleuropein, in a nutritional model of insulin resistance (IR) and NAFLD by high-fat diet. Young male rats were divided into three groups receiving (1) standard diet (STD; 10.5% fat), (2) high-fat diet (HFD; 58.0% fat) and (3) HFD+HT (10 mg/kg/day by gavage). After 5 weeks, the oral glucose tolerance test was performed, and at 6th week, blood sample and tissues (liver and duodenum) were collected for following determinations. The HT-treated rats showed a marked reduction in serum AST, ALT and cholesterol and improved glucose tolerance and insulin sensitivity, reducing homeostasis model assessment index. HT significantly corrected the metabolic impairment induced by HFD, increasing hepatic peroxisome proliferator activated receptor PPAR-α and its downstream-regulated gene fibroblast growth factor 21, the phosphorylation of acetyl-CoA carboxylase and the mRNA carnitine palmitoyltransferase 1a. HT also reduced liver inflammation and nitrosative/oxidative stress decreasing the nitrosylation of proteins, reactive oxygen species production and lipid peroxidation. Moreover, HT restored intestinal barrier integrity and functions (fluorescein isothiocyanate-dextran permeability and mRNA zona occludens ZO-1). Our data demonstrate the beneficial effect of HT in the prevention of early inflammatory events responsible for the onset of IR and steatosis, reducing hepatic inflammation and nitrosative/oxidative stress and restoring glucose homeostasis and intestinal barrier integrity.
Assuntos
Modelos Animais de Doenças , Hepatite/fisiopatologia , Hepatopatia Gordurosa não Alcoólica/terapia , Álcool Feniletílico/análogos & derivados , Animais , Duodeno/fisiopatologia , Masculino , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Álcool Feniletílico/farmacologia , RatosRESUMO
BACKGROUND/OBJECTIVES: Nuclear peroxisome proliferator activated receptor-α (PPAR-α) plays a fundamental role in the regulation of lipid homeostasis and is the target of medications used to treat dyslipidemia. However, little is known about the role of PPAR-α in mouse behavior. METHODS: To investigate the function of Ppar-α in cognitive functions, a behavioral phenotype analysis of mice with a targeted genetic disruption of Ppar-α was performed in combination with neuroanatomical, biochemical and pharmacological manipulations. The therapeutic exploitability of PPAR-α was probed in mice using a pharmacological model of psychosis and a genetic model (BTBR T + tf/J) exhibiting a high rate of repetitive behavior. RESULTS: An unexpected role for brain Ppar-α in the regulation of cognitive behavior in mice was revealed. Specifically, we observed that Ppar-α genetic perturbation promotes rewiring of cortical and hippocampal regions and a behavioral phenotype of cognitive inflexibility, perseveration and blunted responses to psychomimetic drugs. Furthermore, we demonstrate that the antipsychotic and autism spectrum disorder (ASD) medication risperidone ameliorates the behavioral profile of Ppar-α deficient mice. Importantly, we reveal that pharmacological PPAR-α agonist treatment in mice improves behavior in a pharmacological model of ketamine-induced behavioral dysinhibition and repetitive behavior in BTBR T + tf/J mice. CONCLUSION: Our data indicate that Ppar-α is required for normal cognitive function and that pharmacological stimulation of PPAR-α improves cognitive function in pharmacological and genetic models of impaired cognitive function in mice. These results thereby reveal an unforeseen therapeutic application for a class of drugs currently in human use.
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N-Palmitoylethanolamide (PEA) is emerging as a novel therapeutic agent in the treatment of neuropathic pain and neurodegenerative diseases. Unfortunately, PEA poorly reaches the central nervous system (CNS), after peripheral administration, since it is inactivated through intracellular hydrolysis by lipid amidases. Since prodrug approach is one of the most popular methods used to increase cell permeability, the aim of this paper consists in the synthesis of a new galactosyl prodrug of PEA, the palmitoylethanolamide-succinamyl-D-galactos-6'-yl ester (PEAGAL). Biological experiments both in neuroblastoma and in C6 glioma cells, together with quantitative analyses performed through a LC-MS-MS technique, demonstrate the better efficacy of PEAGAL compared to PEA and its higher cell permeation. Our results encourage further experiments in animal models of neuropathic pain and of neurological disorders and/or neurodegenerative diseases, in order to promote a more effective peripherally administrated derivative of PEA.
Assuntos
Analgésicos/farmacologia , Galactose/análogos & derivados , Fármacos Neuroprotetores/farmacologia , Palmitatos/farmacologia , Pró-Fármacos/farmacologia , Amidas , Analgésicos/síntese química , Analgésicos/química , Transporte Biológico/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Estabilidade de Medicamentos , Etanolaminas/metabolismo , Galactose/síntese química , Galactose/química , Galactose/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Nitritos/metabolismo , Oxidopamina/toxicidade , Palmitatos/síntese química , Palmitatos/química , Ácidos Palmíticos/metabolismo , Permeabilidade/efeitos dos fármacos , Pró-Fármacos/síntese química , Pró-Fármacos/químicaRESUMO
Insulin resistance (IR) has been identified as crucial pathophysiological factor in the development and progression of non-alcoholic fatty liver disease (NAFLD). Although mounting evidence suggests that perturbation of gut microflora exacerbates the severity of chronic liver diseases, therapeutic approaches using synbiotic has remained overlooked. Here, we show that a synbiotic composed by Lactobacillus paracasei B21060 plus arabinogalactan and fructo-oligosaccharides lessens NAFLD progression in a rat model of high fat feeding. IR and steatosis were induced by administration of high fat diet (HFD) for 6 weeks. Steatosis and hepatic inflammation, Toll-like receptor (TLR) pattern, glucose tolerance, insulin signaling and gut permeability were studied. Liver inflammatory markers were down-regulated in rats receiving the synbiotic, along with an increased expression of nuclear peroxisome proliferator-activated receptors and expression of downstream target genes. The synbiotic improved many aspects of IR, such as fasting response, hormonal homeostasis and glycemic control. Indeed it prevented the impairment of hepatic insulin signaling, reducing the phosphorylation of insulin receptor substrate-1 in Ser 307 and down-regulating suppressor of cytokine signaling 3. Gene expression analysis revealed that in the liver the synbiotic reduced cytokines synthesis and restored the HFD-dysregulated TLR 2, 4 and 9 mRNAs toward a physiological level of expression. The synbiotic preserved gut barrier integrity and reduced the relative amount of Gram-negative Enterobacteriales and Escherichia coli in colonic mucosa. Overall, our data indicate that the L. paracasei B21060 based synbiotic is effective in reducing the severity of liver injury and IR associated with high fat intake, suggesting its possible therapeutic/preventive clinical utilization.
Assuntos
Fígado Gorduroso/terapia , Lactobacillus , Simbióticos , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Receptor Toll-Like 9/metabolismo , Adiponectina/genética , Adiponectina/metabolismo , Tecido Adiposo/metabolismo , Animais , Dieta Hiperlipídica , Regulação para Baixo , Enterobacteriaceae/efeitos dos fármacos , Galactanos/farmacologia , Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , Resistência à Insulina , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/microbiologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Oligossacarídeos/farmacologia , PPAR gama/genética , PPAR gama/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/genética , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Receptor Toll-Like 9/genéticaRESUMO
Chemical investigation of two species of marine ascidians, Aplidium elegans and Ciona edwardsii, collected in Mediterranean area, led to isolation of a series of alkyl sulfates (compounds 1-5) including three new molecules 1-3. Structures of the new metabolites have been elucidated by spectroscopic analysis. Based on previously reported cytotoxic activity of these type of molecules, compounds 1-3 have been tested for their effects on the growth of two cell lines, J774A.1 (BALB/c murine macrophages) and C6 (rat glioma) in vitro. Compounds 1 and 2 induced selective concentration-dependent mortality on J774A.1 cells.
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Sobrevivência Celular/efeitos dos fármacos , Ésteres do Ácido Sulfúrico/química , Urocordados/química , Animais , Linhagem Celular , Macrófagos/efeitos dos fármacos , Macrófagos/fisiologia , Espectroscopia de Ressonância Magnética , Mar Mediterrâneo , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Ratos , Ésteres do Ácido Sulfúrico/isolamento & purificação , Ésteres do Ácido Sulfúrico/farmacologiaRESUMO
α-Melanocyte-stimulating hormone (α-MSH) is a critical regulator of energy metabolism. Prolyl carboxypeptidase (PRCP) is an enzyme responsible for its degradation and inactivation. PRCP-null mice (PRCP(gt/gt)) showed elevated levels of brain α-MSH, reduced food intake, and a leaner phenotype compared with wild-type controls. In addition, they were protected against diet-induced obesity. Here, we show that PRCP(gt/gt) animals have improved metabolic parameters compared with wild-type controls under a standard chow diet (SD) as well as on a high-fat diet (HFD). Similarly to when they are exposed to SD, PRCP(gt/gt) mice exposed to HFD for 13 wk showed a leaner phenotype due to decreased fat mass, increased energy expenditure, and locomotor activity. They also showed improved insulin sensitivity and glucose tolerance compared with WT controls and a significant reduction in fasting glucose levels. These improvements occured before changes in body weight and composition were evident, suggesting that the beneficial effect of PRCP ablation is independent of the adiposity levels. In support of a reduced gluconeogenesis, liver PEPCK and G-6-Pase mRNA levels were reduced significantly in PRCP(gt/gt) compared with WT mice. A significant decrease in liver weight and hepatic triglycerides were also observed in PRCP(gt/gt) compared with WT mice. Altogether, our data suggest that PRCP is an important regulator of energy and glucose homeostasis since its deletion significantly improves metabolic parameters in mice exposed to both SD and HFD.
Assuntos
Carboxipeptidases/genética , Carboxipeptidases/fisiologia , Dieta Hiperlipídica/efeitos adversos , Obesidade/metabolismo , Animais , Composição Corporal/fisiologia , Peso Corporal/fisiologia , Metabolismo Energético/fisiologia , Ácidos Graxos/metabolismo , Deleção de Genes , Gluconeogênese/genética , Gluconeogênese/fisiologia , Glucose/farmacologia , Teste de Tolerância a Glucose , Homeostase/fisiologia , Hormônios/sangue , Leptina/sangue , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Tamanho do Órgão/fisiologia , Reação em Cadeia da Polimerase em Tempo RealRESUMO
We investigated the involvement of de novo neurosteroid synthesis in the mechanisms underlying the analgesic and antihyperalgesic effects of N-palmitoylethanolamine (PEA) in two models of acute and persistent pain, the formalin test and carrageenan-induced paw edema. The pivotal role of peroxisome proliferator-activated receptor (PPAR)-α in the antinocifensive effect of PEA was confirmed by the lack of this effect in PPAR-α-null mice. PEA antinociceptive activity was partially reduced when the animals were treated with aminoglutethimide or finasteride, implying that de novo neurosteroid synthesis is involved in the effect of PEA. Accordingly, in the spinal cord, the allopregnanolone (ALLO) levels were increased by PEA treatment both in formalin- and carrageenan-exposed mice, as revealed by gas chromatography-mass spectrometry. In agreement with those data, in both pain models, PEA administration in challenged mice specifically restored the expression of two proteins involved in neurosteroidogenensis, the steroidogenic acute regulatory protein (StAR) and cytochrome P450 side-chain cleavage (P450scc) in the ipsilateral horns of spinal cord, without affecting their expression in the contralateral side. These results provide new information about the involvement of de novo neurosteroid synthesis in the modulation of pain behavior by PEA.
Assuntos
Analgésicos/uso terapêutico , Dor/tratamento farmacológico , Ácidos Palmíticos/uso terapêutico , Pregnanolona/biossíntese , Medula Espinal/metabolismo , Amidas , Analgésicos/farmacologia , Animais , Endocanabinoides , Etanolaminas , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Masculino , Camundongos , Dor/metabolismo , Medição da Dor , Ácidos Palmíticos/farmacologia , Medula Espinal/efeitos dos fármacosRESUMO
Ghrelin is a gastric peptide, discovered by Kojima et al. (1999) [55] as a result of the search for an endogenous ligand interacting with the "orphan receptor" GHS-R1a (growth hormone secretagogue receptor type 1a). Ghrelin is composed of 28 aminoacids and is produced mostly by specific cells of the stomach, by the hypothalamus and hypophysis, even if its presence, as well as that of its receptors, has been demonstrated in many other tissues, not least in gonads. Ghrelin potently stimulates GH release and participates in the regulation of energy homeostasis, increasing food intake, decreasing energy output and exerting a lipogenetic effect. Furthermore, ghrelin influences the secretion and motility of the gastrointestinal tract, especially of the stomach, and, above all, profoundly affects pancreatic functions. Despite of these previously envisaged activities, it has recently been hypothesized that ghrelin regulates several aspects of reproductive physiology and pathology. In conclusion, ghrelin not only cooperates with other neuroendocrine factors, such as leptin, in the modulation of energy homeostasis, but also has a crucial role in the regulation of the hypothalamic-pituitary gonadal axis. In the current review we summarize the main targets of this gastric peptide, especially focusing on the reproductive system.
Assuntos
Metabolismo Energético , Grelina/fisiologia , Reprodução , Animais , Feminino , Grelina/sangue , Grelina/farmacologia , Gonadotropinas/metabolismo , Gônadas/fisiologia , Homeostase , Humanos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/fisiologia , Gravidez , Puberdade/efeitos dos fármacos , Puberdade/fisiologia , Ratos , Receptores de Grelina/genética , Receptores de Grelina/fisiologiaRESUMO
Nonalcoholic fatty liver disease (NAFLD) is currently the most common liver disease worldwide, both in adults and in children. NAFLD is characterized by aberrant lipid storage in hepatocytes (hepatic steatosis) and inflammatory progression to nonalcoholic steatohepatitis. Evidences so far suggest that intrahepatic lipid accumulation does not always derive from obesity. Gut microbiota has been considered as a regulator of energy homeostasis and ectopic fat deposition, suggesting its implications in metabolic diseases. Probiotics are live microbial that alter the enteric microflora and have beneficial effects on human health. Although the molecular mechanisms of probiotics have not been completely elucidated yet, many of their effects have proved to be beneficial in NAFLD, including the modulation of the intestinal microbiota, an antibacterial substance production, an improved epithelial barrier function and a reduced intestinal inflammation. Given the close anatomical and functional correlation between the bowel and the liver, and the immunoregulatory effects elicited by probiotics, the aim of this review is to summarize today's knowledge about probiotics in NAFLD, focusing in particular on their molecular and biochemical mechanisms, as well as highlighting their efficacy as an emerging therapeutic strategy to treat this condition.
Assuntos
Fígado Gorduroso/tratamento farmacológico , Probióticos/farmacocinética , Probióticos/uso terapêutico , Animais , Modelos Animais de Doenças , Endotoxemia/terapia , Homeostase , Humanos , Inflamação/tratamento farmacológico , Resistência à Insulina , Intestinos/microbiologia , Intestinos/patologia , Fígado/microbiologia , Fígado/patologia , Metagenoma , Hepatopatia Gordurosa não Alcoólica , Prebióticos/microbiologiaRESUMO
Nonalcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease in the pediatric population. Preliminary evidence suggests a potential therapeutic utility of probiotics for this condition. Here, we tested the potential effect of the probiotic VSL#3 (a multistrain preparation composed of Streptococcus thermophilus and several species of Lactobacillus and Bifidobacteria) on oxidative and inflammatory damage induced by a high-fat diet in the liver of young rats. At weaning, young male Sprague-Dawley rats were randomly divided into 3 groups (n = 6) fed a standard, nonpurified diet (Std; 5.5% of energy from fat) or a high-fat liquid diet (HFD; 71% of energy from fat). One of the HFD groups received by gavage VSL#3 (13 x 10(9) bacteria x kg(-1) x d(-1)). After 4 wk, the HFD rats had greater body weight gain, fat mass, serum aminotransferase, and liver weight than rats fed the Std diet. The HFD induced liver lipid peroxidation, tumor necrosis factor (TNFalpha) production, protein S-nitrosylation, inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2 expression, and metalloproteinase (MMP) activity. Moreover, in the HFD group, PPARalpha expression was less than in rats fed the Std diet. In rats fed the HFD diet and treated with VSL#3, liver TNFalpha levels, MMP-2 and MMP-9 activities, and expression of iNOS and COX-2 were significantly lower than in the HFD group. In VSL#3-treated rats, PPARalpha expression was greater than in the HFD group. A modulation of the nuclear factor-kappaB pathway by VSL#3 was also demonstrated. Our data suggest that VSL#3 administration could limit oxidative and inflammatory liver damage in patients with NAFLD.
Assuntos
Gorduras na Dieta/administração & dosagem , Fígado Gorduroso/prevenção & controle , Hepatite/prevenção & controle , Probióticos/administração & dosagem , Animais , Bifidobacterium , Ciclo-Oxigenase 2/análise , Fígado Gorduroso/etiologia , Hepatite/etiologia , Lactobacillus , Peroxidação de Lipídeos , Fígado/química , Fígado/enzimologia , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Óxido Nítrico Sintase Tipo II/análise , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Streptococcus thermophilus , Fator de Necrose Tumoral alfa/análiseRESUMO
Only in the last few years has non-alcoholic steatohepatitis been recognized as an important and relatively common liver disease. To date, the therapeutic options are limited, vitamin E and metformin have been proposed for the treatment of this condition, although their mechanisms are not completely clarified as yet. The aim of this study was to investigate the anti-inflammatory and anti-oxidative mechanisms of these drugs in an experimental model of non-alcoholic steatohepatitis in the young rat. Male rats, just after weaning, were divided into four groups: a control group that received a standard diet; a high fat diet group; two high fat diet fed groups treated with vitamin E or metformin, respectively. After 4 weeks, we evaluated in the liver the modification of lipid peroxidation, assessed by malondialdehyde, TNF-alpha levels, S-nitrosylated protein, inducible nitric oxide sinthase (iNOS), and peroxisome proliferators-activated receptors (PPAR) expression and metalloproteinase activity. High fat diet increased malondialdehyde, nitrotyrosilated proteins, and TNF-alpha tissue content. Moreover, a decrease of PPAR-alpha and an increase of PPAR-gamma expression were observed. An increase of metalloproteinase activity was also shown. Among drug treatments, metformin reduced body weight gain and fat mass, metalloproteinase activity, and TNF-alpha tissue content, while it restored PPAR-alpha expression and downregulated PPAR-gamma expression. Vitamin E reduced the oxidative damage, protein nitrotyrosilation, and tissue TNF-alpha levels. Moreover a decrease of PPAR-gamma expression was also shown. These findings confirm the efficacy of both drugs as therapeutic tools in preventing the early onset of liver damage and non-alcoholic fatty liver disease progression.
Assuntos
Antioxidantes/uso terapêutico , Fígado Gorduroso/tratamento farmacológico , Fígado/efeitos dos fármacos , Metformina/uso terapêutico , Vitamina E/uso terapêutico , Animais , Antioxidantes/administração & dosagem , Western Blotting , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Fígado Gorduroso/etiologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Masculino , Metformina/administração & dosagem , Ratos , Ratos Sprague-Dawley , Vitamina E/administração & dosagemRESUMO
Leptin and/or ghrelin, initially thought to be considered messengers of energy metabolism, are now considered to play a role in normal and complicated pregnancy. In this study, pregnant, spontaneously hypertensive rats (SHR) have been used to evaluate, for the first time, the modification of leptin and ghrelin both at serum and tissue levels. In SHR, we evaluate plasma leptin level and tissue protein expression in both placenta and adipose tissue at the end of gestation (day 20) versus normotensive Wistar-Kyoto (WKY) animals. The expression of functional leptin receptor (Ob-Rb) in peripheral tissues and in the hypothalamus was evaluated. Moreover, we measured plasma ghrelin level and its mRNA expression in the stomach and placenta. SHR strain presented significantly lower plasma leptin levels when compared with those found in pregnant or not WKY controls. Interestingly, in the placenta, leptin gene expression was higher in SHR than normotensive WKY. Moreover, we demonstrated a resistance to the effects of leptin via 'downregulation' of hypothalamic receptors in pregnant SHR. Conversely, SHR presented significantly higher ghrelin plasma levels when compared with those found in pregnant or not WKY. However, we observed that ghrelin level in the stomach of SHR did not change during pregnancy, and on the opposite, mRNA ghrelin in the placenta of SHR was lower than that of normotensive rats, suggesting a different production of this hormone in the fetal-placental unit. These data gain further insight into metabolic hormone modifications observed in a model of pre-existing hypertension associated with pregnancy.
Assuntos
Adaptação Fisiológica , Grelina/sangue , Hipertensão/metabolismo , Leptina/sangue , Complicações Cardiovasculares na Gravidez/metabolismo , Tecido Adiposo/química , Animais , Feminino , Expressão Gênica , Grelina/análise , Grelina/genética , Hipotálamo/química , Leptina/análise , Modelos Animais , Obesidade/metabolismo , Placenta/química , Gravidez , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Receptores para Leptina/análise , Receptores para Leptina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estômago/químicaRESUMO
Peroxisome proliferator-activated receptor (PPAR)-alpha is a nuclear transcription factor. Although the presence of this receptor in different areas of central nervous system (CNS) has been reported, its role remains unclear. Palmitoylethanolamide (PEA), a member of the fatty-acid ethanolamide family, acts peripherally as an endogenous PPAR-alpha ligand, exerting analgesic and anti-inflammatory effects. High levels of PEA in the CNS have been found, but the specific function of this lipid remains to be clarified. Using carrageenan-induced paw edema in mice, we show that i.c.v. administration of PEA may control peripheral inflammation through central PPAR-alpha activation. A single i.c.v. administration of 0.01 to 1 microg of PEA, 30 min before carrageenan injection, reduced edema formation in the mouse carrageenan test. This effect was mimicked by 0.01 to 1 microg of GW7647 [2-[[4-[2-[[(cyclohexylamino)carbonyl](4-cyclohexylbutyl)amino]ethyl]phenyl]thio]-2-methylpropanoic acid], a synthetic PPAR-alpha agonist. Moreover, central PEA administration significantly reduced the expression of the proinflammatory enzymes cyclooxygenase-2 and inducible nitric-oxide synthase, and it significantly restored carrageenan-induced PPAR-alpha reduction in the spinal cord. To investigate the mechanism by which i.c.v. PEA attenuated the development of carrageenan-induced paw edema, we evaluated inhibitor kappaB-alpha (I kappa B-alpha) degradation and nuclear factor-kappaB (NF-kappaB) p65 activation in the cytosolic or nuclear extracts from spinal cord tissue. PEA prevented IkB-alpha degradation and NF-kappaB nuclear translocation, confirming the involvement of this transcriptional factor in the control of peripheral inflammation. The obligatory role of PPAR-alpha in mediating the effects of PEA was confirmed by the lack of the compounds anti-inflammatory effects in mutant mice lacking PPAR-alpha. In conclusion, our data show for the first time that PPAR-alpha activation in the CNS can control peripheral inflammation.
Assuntos
Edema/tratamento farmacológico , PPAR alfa/agonistas , Ácidos Palmíticos/administração & dosagem , Amidas , Animais , Carragenina , Sistema Nervoso Central , Vias de Administração de Medicamentos , Edema/induzido quimicamente , Endocanabinoides , Etanolaminas , Inflamação/tratamento farmacológico , CamundongosRESUMO
Ochratoxin A (OTA) is a secondary fungal metabolite produced by Aspergillus and Penicillium strains that elicits a broad spectrum of toxicological effects in animals and man. A single oral OTA administration (10 mg/kg) in mice induced after 24 h oxidative damage and polymorphonuclear leukocyte (PMN) infiltration in parenchymal organs. In fact, OTA treatment increased lipid peroxidation (via malondialdehyde formation) in kidney and liver and PMN accumulation in duodenum, as shown by myeloperoxidase activity. Following in vivo OTA treatment an increase of cyclooxygenase-2 and of heat shock protein 72 expression was evidenced in peritoneal macrophage lysates by Western blot. That OTA modulates these proteins involved in the inflammatory process indicates that the mycotoxin is able to activate immune cells. This study suggests that the oxidative stress, the neutrophil accumulation in parenchymal tissues and the modulation of inflammatory parameters in peritoneal macrophages induced by OTA are involved in its toxicity, and represent early events related to several aspects of OTA mycotoxicosis.