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PURPOSE OF REVIEW: Update on the development of microbiome-based interventions and dietary supplements to combat obesity and related comorbidities, which are leading causes of global mortality. RECENT FINDINGS: The role of intestinal dysbiosis, partly resulting from unhealthy diets, in the development of obesity and metabolic disorders, is well documented by recent translational research. Human experimental trials with whole-faecal transplants are ongoing, and their results will be crucial as proof of concept that interventions intended to modulate the microbiome composition and function could be alternatives for the management of obesity and related comorbidities. Potential next-generation probiotic bacteria (Akkermansia, Bacteroides spp., Eubacterium halli) and microbiota-derived molecules (e.g. membrane proteins, short-chain fatty acids) are being evaluated in preclinical and clinical trials to promote the development of innovative dietary supplements. The fact that live or inactivated bacteria and their products can regulate pathways that increase energy expenditure, and reduce energy intake, and absorption and systemic inflammation make them attractive research targets from a nutritional and clinical perspective. SUMMARY: Understanding which are the beneficial bacteria and their bioactive products is helping us to envisage innovative microbiome-based dietary interventions to tackle obesity. Advances will likely result from future refinements of these strategies according to the individual's microbiome configuration and its particular response to interventions, thereby progressing towards personalized nutrition.
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Dieta , Microbioma Gastrointestinal , Probióticos , Animais , Bacteroides , Gerenciamento Clínico , Modelos Animais de Doenças , Eubacterium , Ácidos Graxos Voláteis/metabolismo , Trato Gastrointestinal/microbiologia , Humanos , Proteínas de Membrana/metabolismo , Obesidade/terapiaRESUMO
Pruritus is a common symptom in chronic liver diseases, which may also alter thermal sensitivity. The underlying mechanisms remain unclear and treatments are not satisfactory. Portal-systemic shunting has been proposed to alter thermal sensitivity in cirrhotics. Inflammation-induced enhanced activity of the Transient Receptor Potential Vanilloid 1 (TRPV1) may contribute to pruritus and thermal hyperalgesia. Sildenafil reduces neuroinflammation in portacaval shunt (PCS) rats. The aims were to assess whether: (1) PCS rats show enhanced scratching or thermal sensitivity; (2) TRPV1 activity is enhanced in PCS rats; (3) treatment with sildenafil reduces TRPV1 activation, scratching and thermal hyperalgesia. Rats were treated with sildenafil beginning 3 weeks after surgery. The number of scratches performed were counted. Thermal hyperalgesia was analyzed using the Hargreaves' Plantar Test. TRPV1 activation by measuring the increase in Ca2+ induced by capsaicin in dorsal root ganglia neurons. PCS rats show enhanced scratching behavior, reaching 66 ± 5 scratches/h (p < 0.01) at 21 days after surgery, while controls show 37 ± 2 scratches/h. PCS rats show thermal hyperalgesia. Paw withdrawal latency was reduced (p < 0.05) to 10 ± 1 s compared to controls (21 ± 2 s). Capsaicin-induced calcium increase was higher in dorsal root ganglia cultures from PCS rats, indicating TRPV1functional increase. PCS rats show enhanced scratching behavior and thermal sensitivity and are a good model to study these alterations in chronic liver diseases. Enhanced sensitivity and activity of TRPV1 channel underlies these alterations. Treatment with sildenafil reduces TRPV1 channel sensitivity and activity and normalizes scratching behavior and thermal sensitivity.
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Hiperalgesia/tratamento farmacológico , Inibidores da Fosfodiesterase 5/farmacologia , Derivação Portocava Cirúrgica , Prurido/tratamento farmacológico , Citrato de Sildenafila/farmacologia , Animais , Cálcio/metabolismo , Gânglios Espinais/citologia , Temperatura Alta , Hiperalgesia/fisiopatologia , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Inibidores da Fosfodiesterase 5/uso terapêutico , Prurido/fisiopatologia , Ratos Wistar , Citrato de Sildenafila/uso terapêutico , Canais de Cátion TRPV/agonistas , Canais de Cátion TRPV/metabolismoRESUMO
ANTECEDENTS: Given the contradictions of previous studies on the changes in attentional responses produced in aging a Stroop emotional task was proposed to compare young and older adults to words or faces with an emotional valence. METHOD: The words happy or sad were superimposed on faces that express the emotion of happiness or sadness. The emotion expressed by the word and the face could agree or not (cued and uncued trials, respectively). 85 young and 66 healthy older adults had to identify both faces and words separately, and the interference between the two types of stimuli was examined. RESULTS: An interference effect was observed for both types of stimuli in both groups. There was more interference on positive faces and words than on negative stimuli. CONCLUSIONS: Older adults had more difficulty than younger in focusing on positive uncued trials, whereas there was no difference across samples on negative uncued trials.
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Envelhecimento/fisiologia , Atenção/fisiologia , Emoções/fisiologia , Expressão Facial , Reconhecimento Visual de Modelos/fisiologia , Desempenho Psicomotor/fisiologia , Leitura , Teste de Stroop , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Reconhecimento Facial/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: Patients with liver cirrhosis and minimal hepatic encephalopathy (MHE) show mild cognitive impairment and spatial learning dysfunction. Hyperammonemia acts synergistically with inflammation to induce cognitive impairment in MHE. Hyperammonemia-induced neuroinflammation in hippocampus could contribute to spatial learning impairment in MHE. Two main aims of this work were: (1) to assess whether chronic hyperammonemia increases inflammatory factors in the hippocampus and if this is associated with microglia and/or astrocytes activation and (2) to assess whether hyperammonemia-induced neuroinflammation in the hippocampus is associated with altered membrane expression of glutamate and GABA receptors and spatial learning impairment. There are no specific treatments for cognitive alterations in patients with MHE. A third aim was to assess whether treatment with sulforaphane enhances endogenous the anti-inflammatory system, reduces neuroinflammation in the hippocampus of hyperammonemic rats, and restores spatial learning and if normalization of receptor membrane expression is associated with learning improvement. METHODS: We analyzed the following in control and hyperammonemic rats, treated or not with sulforaphane: (1) microglia and astrocytes activation by immunohistochemistry, (2) markers of pro-inflammatory (M1) (IL-1ß, IL-6) and anti-inflammatory (M2) microglia (Arg1, YM-1) by Western blot, (3) membrane expression of GABA, AMPA, and NMDA receptors using the BS3 cross-linker, and (4) spatial learning using the radial maze. RESULTS: The results reported show that hyperammonemia induces astrocytes and microglia activation in the hippocampus, increasing pro-inflammatory cytokines IL-1ß and IL-6. This is associated with altered membrane expression of AMPA, NMDA, and GABA receptors which would be responsible for altered neurotransmission and impairment of spatial learning in the radial maze. Treatment with sulforaphane promotes microglia differentiation from pro-inflammatory M1 to anti-inflammatory M2 phenotype and reduces activation of astrocytes in hyperammonemic rats. This reduces neuroinflammation, normalizes membrane expression of glutamate and GABA receptors, and restores spatial learning in hyperammonemic rats. CONCLUSIONS: Hyperammonemia-induced neuroinflammation impairs glutamatergic and GABAergic neurotransmission by altering membrane expression of glutamate and GABA receptors, resulting in impaired spatial learning. Sulforaphane reverses all these effects. Treatment with sulforaphane could be useful to improve cognitive function in cirrhotic patients with minimal or clinical hepatic encephalopathy.
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Anti-Inflamatórios/uso terapêutico , Encefalite/etiologia , Hipocampo/metabolismo , Hiperamonemia/complicações , Isotiocianatos/uso terapêutico , Deficiências da Aprendizagem , Receptores de Neurotransmissores/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Peso Corporal/efeitos dos fármacos , Citocinas/metabolismo , Modelos Animais de Doenças , Encefalite/tratamento farmacológico , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Hipocampo/patologia , Hiperamonemia/patologia , Técnicas In Vitro , Isotiocianatos/farmacologia , Deficiências da Aprendizagem/tratamento farmacológico , Deficiências da Aprendizagem/etiologia , Deficiências da Aprendizagem/patologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Ratos , Ratos Wistar , Aprendizagem Espacial/efeitos dos fármacos , Aprendizagem Espacial/fisiologia , SulfóxidosRESUMO
BACKGROUND: Hyperammonemia induces neuroinflammation and increases GABAergic tone in the cerebellum which contributes to cognitive and motor impairment in hepatic encephalopathy (HE). The link between neuroinflammation and GABAergic tone remains unknown. New treatments reducing neuroinflammation and GABAergic tone could improve neurological impairment. The aims were, in hyperammonemic rats, to assess whether: (a) Enhancing endogenous anti-inflammatory mechanisms by sulforaphane treatment reduces neuroinflammation and restores learning and motor coordination. (b) Reduction of neuroinflammation by sulforaphane normalizes extracellular GABA and glutamate-NO-cGMP pathway and identify underlying mechanisms. (c) Identify steps by which hyperammonemia-induced microglial activation impairs cognitive and motor function and how sulforaphane restores them. METHODS: We analyzed in control and hyperammonemic rats, treated or not with sulforaphane, (a) learning in the Y maze; (b) motor coordination in the beam walking; (c) glutamate-NO-cGMP pathway and extracellular GABA by microdialysis; (d) microglial activation, by analyzing by immunohistochemistry or Western blot markers of pro-inflammatory (M1) (IL-1b, Iba-1) and anti-inflammatory (M2) microglia (Iba1, IL-4, IL-10, Arg1, YM-1); and (e) membrane expression of the GABA transporter GAT-3. RESULTS: Hyperammonemia induces activation of astrocytes and microglia in the cerebellum as assessed by immunohistochemistry. Hyperammonemia-induced neuroinflammation is associated with increased membrane expression of the GABA transporter GAT-3, mainly in activated astrocytes. This is also associated with increased extracellular GABA in the cerebellum and with motor in-coordination and impaired learning ability in the Y maze. Sulforaphane promotes polarization of microglia from the M1 to the M2 phenotype, reducing IL-1b and increasing IL-4, IL-10, Arg1, and YM-1 in the cerebellum. This is associated with astrocytes deactivation and normalization of GAT-3 membrane expression, extracellular GABA, glutamate-nitric oxide-cGMP pathway, and learning and motor coordination. CONCLUSIONS: Neuroinflammation increases GABAergic tone in the cerebellum by increasing GAT-3 membrane expression. This impairs motor coordination and learning in the Y maze. Sulforaphane could be a new therapeutic approach to improve cognitive and motor function in hyperammonemia, hepatic encephalopathy, and other pathologies associated with neuroinflammation by promoting microglia differentiation from M1 to M2.
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Proteínas da Membrana Plasmática de Transporte de GABA/biossíntese , Encefalopatia Hepática/metabolismo , Hiperamonemia/metabolismo , Microglia/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Western Blotting , Membrana Celular/metabolismo , Cerebelo , Modelos Animais de Doenças , Encefalopatia Hepática/complicações , Hiperamonemia/etiologia , Hiperamonemia/fisiopatologia , Imuno-Histoquímica , Inflamação/metabolismo , Isotiocianatos/farmacologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Microdiálise , Microglia/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Ratos , Ratos Wistar , Sulfóxidos , Ácido gama-Aminobutírico/metabolismoRESUMO
BACKGROUND: Peripheral inflammation contributes to the neurological alterations in hepatic encephalopathy (HE). Neuroinflammation and altered GABAergic neurotransmission mediate cognitive and motor alterations in rats with HE. It remains unclear (a) if neuroinflammation and neurological impairment in HE are a consequence of peripheral inflammation and (b) how neuroinflammation impairs GABAergic neurotransmission. The aims were to assess in rats with HE whether reducing peripheral inflammation with anti-TNF-α (1) prevents cognitive impairment and motor in-coordination, (2) normalizes neuroinflammation and extracellular GABA in the cerebellum and also (3) advances the understanding of mechanisms linking neuroinflammation and increased extracellular GABA. METHODS: Rats with HE due to portacaval shunt (PCS) were treated with infliximab. Astrocytes and microglia activation and TNF-α and IL-1ß were analyzed by immunohistochemistry. Membrane expression of the GABA transporters GAT-3 and GAT-1 was analyzed by cross-linking with BS3. Extracellular GABA was analyzed by microdialysis. Motor coordination was tested using the beam walking and learning ability using the Y maze task. RESULTS: PCS rats show peripheral inflammation, activated astrocytes, and microglia and increased levels of TNF-α and IL-1ß. Membrane expression of GAT-3 and extracellular GABA are increased, leading to impaired motor coordination and learning ability. Infliximab reduces peripheral inflammation, microglia, and astrocyte activation and neuroinflammation and normalizes GABAergic neurotransmission, motor coordination, and learning ability. CONCLUSIONS: Neuroinflammation is associated with altered GABAergic neurotransmission and increased GAT-3 membrane expression and extracellular GABA (a); peripheral inflammation is a main contributor to the impairment of motor coordination and of the ability to learn the Y maze task in PCS rats (b); and reducing peripheral inflammation using safe procedures could be a new therapeutic approach to improve cognitive and motor function in patients with HE
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Cerebelo/metabolismo , Encefalopatia Hepática/patologia , Inflamação/tratamento farmacológico , Infliximab/uso terapêutico , Deficiências da Aprendizagem/tratamento farmacológico , Transtornos Psicomotores/tratamento farmacológico , Ácido gama-Aminobutírico/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , GMP Cíclico/metabolismo , Citocinas/metabolismo , Dinoprostona/metabolismo , Modelos Animais de Doenças , Líquido Extracelular/metabolismo , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Encefalopatia Hepática/complicações , Inflamação/etiologia , Infliximab/farmacologia , Deficiências da Aprendizagem/etiologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos Psicomotores/etiologia , Ratos , Ratos WistarRESUMO
Hepatic encephalopathy (HE) is one of the primary complications of liver cirrhosis. Current treatments for HE, mainly directed to reduction of ammonia levels, are not effective enough because they cannot completely eliminate hyperammonemia and inflammation, which induce the neurological alterations. Studies in animal models show that overactivation of GABAA receptors is involved in cognitive and motor impairment in HE and that reducing this activation restores these functions. We have developed a new compound, GR3027, that selectively antagonizes the enhanced activation of GABAA receptors by neurosteroids such as allopregnanolone and 3α,21-dihydroxy-5α-pregnan-20-one (THDOC). This work aimed to assess whether GR3027 improves motor incoordination, spatial learning, and circadian rhythms of activity in rats with HE. GR3027 was administered subcutaneously to two main models of HE: rats with chronic hyperammonemia due to ammonia feeding and rats with portacaval shunts (PCS). Motor coordination was assessed in beam walking and spatial learning and memory in the Morris water maze and the radial maze. Circadian rhythms of ambulatory and vertical activity were also assessed. In both hyperammonemic and PCS rats, GR3027 restores motor coordination, spatial memory in the Morris water maze, and spatial learning in the radial maze. GR3027 also partially restores circadian rhythms of ambulatory and vertical activity in PCS rats. GR3027 is a novel approach to treatment of HE that would normalize neurological functions altered because of enhanced GABAergic tone, affording more complete normalization of cognitive and motor function than current treatments for HE.
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Desoxicorticosterona/análogos & derivados , Encefalopatia Hepática/tratamento farmacológico , Hidroxiesteroides/uso terapêutico , Hiperamonemia/tratamento farmacológico , Locomoção , Aprendizagem em Labirinto , Pregnanolona/farmacologia , Receptores de GABA-A/metabolismo , Animais , Ritmo Circadiano , Desoxicorticosterona/farmacologia , Antagonismo de Drogas , Células HEK293 , Humanos , Hidroxiesteroides/farmacologia , Masculino , Ratos , Ratos WistarRESUMO
BACKGROUND: There are no specific treatments for the neurological alterations of cirrhotic patients with minimal hepatic encephalopathy (MHE). Rats with MHE due to portacaval shunt (PCS) show impaired spatial learning. The underlying mechanisms remain unknown. The aims of this work were to assess: (a) whether PCS rats show neuroinflammation in hippocampus, (b) whether treatment with sildenafil reduces neuroinflammation and restores spatial learning in PCS rats, and (c) analyze the underlying mechanisms. METHODS: Neuroinflammation was assessed by determining inflammatory markers by Western blot. Phosphorylation of MAP-kinase p38 was assessed by immunohistochemistry. Membrane expression of GABA and glutamate receptors was analyzed using BS3 cross-linker. Spatial learning was analyzed using the radial and Morris water mazes. To assess if sildenafil reverses the alterations, rats were treated with sildenafil in the drinking water. RESULTS: PCS rats show increased IL-1ß and TNF-α levels and phosphorylation (activity) of p38 in hippocampus. Membrane expression of subunits α1 of GABAA receptor and GluR2 of AMPA receptor are increased in PCS rats, while subunits GluR1 of AMPA receptors and NR1 and NR2a of NMDA receptors are reduced. PCS rats show reduced spatial learning in the radial and Morris water mazes. Sildenafil treatment normalizes IL-1ß and TNF-α levels, p38 phosphorylation, and membrane expression of GABAA, AMPA, and NMDA receptors and restores spatial learning. CONCLUSIONS: Increased IL-1ß alters GABAergic and glutamatergic neurotransmission in hippocampus and impairs spatial learning in rats with MHE. Sildenafil reduces neuroinflammation and restores learning. Phosphodiesterase-5 inhibitors may be useful to improve cognitive function in patients with MHE.
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Encefalopatia Hepática/tratamento farmacológico , Encefalopatia Hepática/psicologia , Inflamação/tratamento farmacológico , Aprendizagem em Labirinto/efeitos dos fármacos , Citrato de Sildenafila/uso terapêutico , Vasodilatadores/uso terapêutico , Animais , Encefalopatia Hepática/patologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Inflamação/patologia , Interleucina-1beta/metabolismo , Ativação de Macrófagos/efeitos dos fármacos , Masculino , Microglia/efeitos dos fármacos , Derivação Portocava Cirúrgica , Ratos , Ratos Wistar , Receptores de GABA/biossíntese , Receptores de Glutamato/biossíntese , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
BACKGROUND & AIMS: Low-grade cytotoxic oedema is considered a main contributor to the neurological (motor and cognitive) alterations in patients with hepatic encephalopathy (HE). This assumption is mainly based on studies with cultured astrocytes treated with very large ammonia concentrations or with animal models of acute liver failure with strong HE. However, the possible contribution of cerebral oedema (vasogenic or cytotoxic) to cognitive or motor alterations in chronic mild HE has not been demonstrated. The aim of this work was to assess whether cerebral oedema contributes to cognitive and/or motor alterations in rats with chronic mild HE. METHODS: Motor activity and coordination and different types of learning and memory were assessed in rats with porta-caval shunts (PCS). Brain oedema was assessed by gravimetry in cerebellum and cortex and apparent diffusion coefficient (ADC) by magnetic resonance in 16 areas. RESULTS: Four weeks after surgery, PCS rats show reduced motor activity and coordination, impaired ability to learn a conditional discrimination task in the Y maze and reduced spatial memory in the Morris water maze. PCS rats did not show increased brain water content at 4 or 10 weeks or changes in ADC at 4 weeks. At 10 weeks, increased ADC in some areas is compatible with vasogenic but not cytotoxic oedema. CONCLUSION: Cerebral oedema is not involved in motor and cognitive alterations in rats (and likely in humans) with mild HE. Proper understanding of the mechanisms responsible for the neurological alterations in HE is necessary to design efficient treatments.
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Edema Encefálico/diagnóstico , Cerebelo/diagnóstico por imagem , Encefalopatia Hepática/complicações , Animais , Cognição , Modelos Animais de Doenças , Imageamento por Ressonância Magnética , Masculino , Aprendizagem em Labirinto , Memória , Atividade Motora , Derivação Portocava Cirúrgica , Cintilografia , Ratos , Ratos WistarRESUMO
Neuroinflammation plays a main role in neurological deficits in rats with minimal hepatic encephalopathy (MHE) due to portacaval shunt (PCS). Treating PCS rats with SB239063, an inhibitor of MAP-kinase-p38, reduces microglial activation and brain inflammatory markers and restores cognitive and motor function. The translocator protein-(18-kDa) (TSPO) is considered a biomarker of neuroinflammation. TSPO is increased in brain of PCS rats and of cirrhotic patients that died in hepatic coma. Rats with MHE show strong microglial activation in cerebellum and milder in other areas when assessed by MHC-II immunohistochemistry. This work aims were assessing: 1) whether binding of TSPO ligands is selectively increased in cerebellum in PCS rats; 2) whether treatment with SB239063 reduces binding of TSPO ligands in PCS rats; 3) which cell type (microglia, astrocytes) increases TSPO expression. Quantitative autoradiography was used to assess TSPO-selective (3)H-(R)-PK11195 binding to different brain areas. TSPO expression increased differentially in PCS rats, reaching mild expression in striatum or thalamus and very high levels in cerebellum. TSPO was expressed in astrocytes and microglia. Treatment with SB239063 did not reduces (3)[H]-PK11195 binding in PCS rats. SB239063 reduces microglial activation and levels of inflammatory markers, but not binding of TSPO ligands. This indicates that SB239063-induced neuroinflammation reduction in PCS rats is not mediated by effects on TSPO. Also, enhanced TSPO expression is not always associated with cognitive or motor deficits. If enhanced TSPO expression plays a role in mechanisms leading to neurological alterations in MHE, SB239063 would interfere these mechanisms at a later step.
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Encéfalo/metabolismo , Proteínas de Transporte/metabolismo , Encefalopatia Hepática/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Derivação Portocava Cirúrgica/efeitos adversos , Receptores de GABA-A/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Animais , Biomarcadores , Modelos Animais de Doenças , Encefalopatia Hepática/etiologia , Imidazóis/farmacologia , Isoquinolinas/metabolismo , Masculino , Microglia/metabolismo , Especificidade de Órgãos , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Ratos , Ratos WistarRESUMO
Several neurosteroids modulate the glutamate-nitric oxide (NO)-cGMP pathway in cerebellum through modulation of NMDA- GABAA - or sigma receptors. Hyperammonemia alters the concentration of several neurosteroids and impairs the glutamate-NO-cGMP pathway, leading to impaired learning ability. This work aimed to assess whether chronic hyperammonemia alters the modulation by different neurosteroids of GABAA, NMDA, and/or sigma receptors and of the glutamate-NO-cGMP pathway in cerebellum. Neurosteroids were administered through microdialysis probes, and extracellular cGMP and citrulline were measured. Then NMDA was administered to assess the effects on the glutamate-NO-cGMP pathway activation. Hyperammonemia completely modifies the effects of pregnanolone and pregnenolone. Pregnanolone acts as a GABAA receptor agonist in controls, but as an NMDA receptor antagonist in hyperammonemic rats. Pregnenolone does not induce any effect in controls, but acts as a sigma receptor agonist in hyperammonemic rats. Hyperammonemia potentiates the actions of tetrahydrodeoxy-corticosterone (THDOC) as a GABAA receptor agonist, allopregnanolone as an NMDA receptor antagonist, and pregnenolone sulfate as an NMDA receptor activation enhancer. Neurosteroids that reduce the pathway (pregnanolone, THDOC, allopregnanolone, DHEAS) may contribute to cognitive impairment in hyperammonemia and hepatic encephalopathy. Pregnenolone would impair cognitive function in hyperammonemia. Neurosteroids that restore the pathway in hyperammonemia (pregnenolone sulfate) could restore cognitive function in hyperammonemia and encephalopathy.
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Cerebelo/metabolismo , GMP Cíclico/metabolismo , Ácido Glutâmico/metabolismo , Hiperamonemia/metabolismo , Neurotransmissores/metabolismo , Óxido Nítrico/metabolismo , Receptores de GABA-A/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores sigma/metabolismo , Animais , Citrulina/metabolismo , Espaço Extracelular/metabolismo , Masculino , N-Metilaspartato/farmacologia , Óxido Nítrico Sintase Tipo I/metabolismo , Ratos , Ratos WistarRESUMO
This mini-review focus on our studies on alterations in glutamatergic neurotransmission and their role in neurological alterations in rat models of chronic hyperammonemia and hepatic encephalopathy (HE). Hyperammonemia impairs the glutamate-nitric oxide (NO)-cGMP pathway in cerebellum, which is responsible for reduced learning ability. We studied the underlying mechanisms and designed treatments to restore the pathway and learning. This was achieved by treatment with: phosphodiesterase 5 inhibitors, cGMP, anti-inflammatories (ibuprofen), p38 inhibitors or GABAA receptor antagonists (bicuculline). Hyperammonemia alters signal transduction associated to metabotropic glutamate receptors (mGluRs). Hypokinesia in hyperammonemia and HE is due to increased extracellular glutamate and mGluR1 activation in substantia nigra; blocking this receptor restores motor activity. The motor responses to mGluRs activation in nucleus accumbens (NAcc) are altered in hyperammonemia and HE, with reduced dopamine and increased glutamate release. This leads to activation of different neuronal circuits and enhanced motor responses. These studies show that altered responses to activation of NMDA receptors and mGluRs play essential roles in cognitive and motor alterations in hyperammonemia and HE and provide new treatments restoring cognitive and motor function.
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Ácido Glutâmico/fisiologia , Hiperamonemia/fisiopatologia , Doenças do Sistema Nervoso/fisiopatologia , Transmissão Sináptica/fisiologia , Animais , Doença Crônica , Transtornos Cognitivos/etiologia , Humanos , Hiperamonemia/complicações , Doenças do Sistema Nervoso/etiologiaRESUMO
Exposure to early life stress (ELS), prenatal or postnatal during childhood and adolescence, can significantly impact mental and physical health. The role of the intestinal microbiome in human health, and particularly mental health, is becoming increasingly evident. This systematic review aims to summarize the clinical data evaluating the effect of ELS on the human intestinal microbiome. The systematic review (CRD42022351092) was performed following PRISMA guidelines, with ELS considered as exposure to psychological stressors prenatally and during early life (childhood and adolescence). Thirteen articles met all inclusion criteria, and all studies reviewed found a link between ELS and the gut microbiome in both prenatal and postnatal periods. However, we failed to find consensus microbiome signatures associated with pre- or postnatal stress, or both. The inconsistency of results is likely attributed to various factors such as different experimental designs, ages examined, questionnaires, timing of sample collection and analysis methods, small population sizes, and the type of stressors. Additional studies using similar stressors and validated stress measures, as well as higher-resolution microbiome analytical approaches, are needed to draw definitive conclusions about the links between stress and the human gut microbiome.
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Experiências Adversas da Infância , Microbioma Gastrointestinal , Microbiota , Feminino , Gravidez , Adolescente , Humanos , Saúde Mental , Estresse PsicológicoRESUMO
Studies that analyze the predictors of satisfaction with the health of the elderly are scarce. That is the reason why the objective of this study is to analyze whether the physical-psychological state, sports practice, and the use of socio-health resources are factors that predict satisfaction with health status in physically active elderly people. The Physical Activity and Quality of Life questionnaires were applied to a sample of 397 elderly people in this cross-sectional observational study. The data have been analyzed using Student's t-test chi-square test, Cohen's d, Phi Coefficient and Cramer's V. The results have shown that the lack of physical illnesses (OR = 3.920; p < 0.001) and psychological problems (OR = 1.940; p = 0.032), practicing a high level of physical activity (OR = 2.049; p = 0.001), having high scores in functional skills (OR = 8.059; p < 0.001) and using little social and health services (OR = 2.595; p < 0.001) are all predictors of being highly satisfied with one's health. In conclusion, predictors associated with high health satisfaction of active older people have been found, such as functional abilities, the existence of physical illness, psychological problems, level of physical activity, frequency of use of health and social services and satisfaction with health and social services; but it is not associated with gender or age of participants.
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BACKGROUND & AIMS: Patients with acute liver failure (ALF) often die of intracranial pressure (IP) and cerebral herniation. Main contributors to increased IP are ammonia, glutamine, edema, and blood flow. The sequence of events and underlying mechanisms, as well as the temporal pattern, regional distribution, and contribution of each parameter to the progression of neurologic deterioration and IP, are unclear. We studied rats with ALF to follow the progression of changes in ammonia, glutamine, grade and type (vasogenic or cytotoxic) of edema, blood-brain barrier permeability, cerebral blood flow, and IP. We assessed whether the changes in these parameters were similar between frontal cortex and cerebellum and evaluated the presence, type, and progression of edema in 12 brain areas. METHODS: ALF was induced by injection of galactosamine. The grade and type of edema was assessed by measuring the apparent diffusion coefficient by magnetic resonance imaging. Cerebral blood flow was measured by magnetic resonance and blood-brain barrier permeability by Evans blue-albumin extravasation. RESULTS: Increased IP arises from an early increase of blood-brain barrier permeability in certain areas (including cerebellum but not frontal cortex) followed by vasogenic edema. Ammonia and glutamine then increase progressively, leading to cytotoxic edema in many areas. Alterations in lactate and cerebral blood flow are later events that further increase IP. CONCLUSIONS: Different mechanisms in specific regions of the brain contribute, with different temporal patterns, to the progression of cerebral alterations and IP in ALF.
Assuntos
Edema Encefálico/etiologia , Cérebro/fisiopatologia , Encefalocele/etiologia , Hipertensão Intracraniana/etiologia , Falência Hepática Aguda/complicações , Amônia/sangue , Animais , Barreira Hematoencefálica/fisiopatologia , Edema Encefálico/fisiopatologia , Permeabilidade Capilar , Cerebelo/irrigação sanguínea , Cerebelo/fisiopatologia , Cérebro/irrigação sanguínea , Galactosamina/efeitos adversos , Glutamina/sangue , Hipertensão Intracraniana/fisiopatologia , Ácido Láctico/sangue , Ácido Láctico/metabolismo , Falência Hepática Aguda/induzido quimicamente , Masculino , Ratos , Ratos WistarRESUMO
OBJECTIVE: Inflammation plays a role in neurological alterations in patients with hepatic encephalopathy (HE). Animal models of HE show neuroinflammation. Treatment with ibuprofen, a non-steroidal anti-inflammatory drug (NSAID), reduces neuroinflammation and restores cognitive and motor function in rats with HE due to portacaval shunts (PCS). This suggests that reducing neuroinflammation would improve neurological status in patients with minimal or clinical HE. NSAID induce kidney damage in patients with cirrhosis and PCS rats and are not suitable for clinical use. It is therefore necessary to look for procedures to eliminate neuroinflammation without inducing secondary effects in the kidney. Inhibition of p38 MAPK is being tested as a therapeutic target in inflammatory diseases and reduces microglial activation. This study aimed to assess whether inhibiting p38 with SB239063 reduces neuroinflammation and improves cognitive and motor function in PCS rats without affecting the kidney. RESULTS: p38 activity is increased in the brains of PCS rats and treatment with SB239063 reduces microglial activation, as well as inflammatory markers in brain (prostaglandin E2, cyclooxygenase activity, iNOS, IL-1ß, TNFα) and blood (prostaglandin E2 and TNFα). PCS rats showed increased ammonia and glutamine in the brain, which was not affected by SB239063. PCS rats showed reduced ability to learn a Y-maze conditional discrimination task, reduced motor activity and impaired motor coordination, as assessed in the rotarod. Treatment with SB239063 completely restored learning ability, motor activity and coordination in PCS rats. SB239063 did not affect creatinine or sodium levels in serum, indicating that it does not induce kidney damage. CONCLUSION: These findings suggest that reducing neuroinflammation by using inhibitors of p38 would improve the neurological status in HE without inducing secondary effects in the kidney.
Assuntos
Encefalopatia Hepática/tratamento farmacológico , Imidazóis/farmacologia , Pirimidinas/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Amônia/sangue , Animais , Western Blotting , Cerebelo/metabolismo , Córtex Cerebral/metabolismo , Cognição/efeitos dos fármacos , Modelos Animais de Doenças , Glutamina/sangue , Imuno-Histoquímica , Aprendizagem/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Microglia/efeitos dos fármacos , Microglia/fisiologia , Atividade Motora/efeitos dos fármacos , Fosforilação , Derivação Portocava Cirúrgica , Prostaglandina-Endoperóxido Sintases/metabolismo , Ratos , Ratos WistarRESUMO
Background: Postoperative cognitive dysfunction affects the quality of recovery, particularly affecting the elderly, and poses a burden on the health system. We hypothesize that the use of sugammadex (SG) could optimize the quality of postoperative cognitive function and overall recovery through a neuroprotective effect. Methods: A pilot observational study on patients undergoing cardiac surgery with enhanced recovery after cardiac surgery (ERACS) approach, was designed to compare SG-treated (n = 14) vs. neostigmine (NG)-treated (n = 7) patients. The Postoperative Quality Recovery Scale (PQRS) was used at different times to evaluate cognitive function and overall recovery of the patients. An online survey among anesthesiologists on SG use was also performed. Additionally, an animal model study was designed to explore the effects of SG on the hippocampus. Results: Sugammadex (SG) was associated with favorable postoperative recovery in cognitive domains particularly 30 days after surgery in patients undergoing aortic valve replacement by cardiopulmonary bypass and the ERACS approach; however, it failed to demonstrate a short-term decrease in length of intensive care unit (ICU) and hospital stay. The survey information indicated a positive appreciation of SG recovery properties. SG reverts postoperative memory deficit and induces the expression of anti-inflammatory microglial markers. Conclusion: The results show a postoperative cognitive improvement by SG treatment in patients undergoing aortic valve replacement procedure by the ERACS approach. Additionally, experimental data from an animal model of mild surgery confirm the cognitive effect of SG and suggest a potential effect over glia cells as an underlying mechanism.
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Incidence of bilateral risk-reducing mastectomies (RRMs) is increasing. The aim of this study was to compare satisfaction, aesthetic and oncological outcomes in women undergoing RRM with implant-based reconstruction comparing nipple-sparing mastectomy (NSM) with skin-sparing mastectomy (SSM) (sacrificing the nipple +/− nipple reconstruction). Women who had undergone bilateral RRM between 1997 and 2016 were invited. Aesthetic outcome and nipple symmetry were evaluated using standardized anthropometric measurements. The oncological outcome was assessed at last documented follow up. Ninety-three women (186 breasts) participated, 60 (64.5%) had NSM, 33 (35.5%) SSM. Median time between surgery and participation was 98.4 months (IQR: 61.7−133.9). Of the women, 23/33 (69.7%) who had SSM underwent nipple reconstruction. Nipple projection was shorter in the reconstructed SSM group than the maintained NSM group (p < 0.001). There was no significant difference in overall symmetry (p = 0.670), satisfaction regarding nipple preservation (p = 0.257) or overall nipple satisfaction (p = 0.074). There were no diagnoses of breast cancer at a median follow up of 129 months (IQR: 65−160.6). Women who undergo nipple-sparing RRM maintain long-term nipple symmetry. Nipple projection was less maintained after nipple reconstruction. Although satisfaction with the nipples was higher in the NSM group, this did not reach statistical significance. No breast cancers developed after RRM with long-term follow up.
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BACKGROUND & AIMS: Hyperammonemia and inflammation cooperate to induce neurological alterations in hepatic encephalopathy. Recent studies in animal models suggest that chronic hyperammonemia and neuroinflammation impair learning ability by the same mechanism. Chronic hyperammonemia might induce inflammatory factors in the brain that impair cognitive function. We sought to determine whether hyperammonemia itself induces neuroinflammation, whether ammonia-induced neuroinflammation mediates cognitive impairment, and whether neuroinflammation also occurs in rats with bile duct ligation (BDL rats)-a model of chronic liver injury that results in hyperammonemia and hepatic encephalopathy. METHODS: Chronic moderate hyperammonemia was induced by feeding male Wistar rats an ammonium-containing diet or performing BDL. Rats that received a standard diet or a sham operation were used as controls. Neuroinflammation was assessed by measuring activation of microglia and inflammatory factors. Brain samples were collected from hyperammonemic and BDL rats; microglial activation was determined by immunohistochemistry and quantification of inflammatory markers (ie, inducible nitric oxide synthase, interleukin-1beta, and prostaglandin E2). Learning ability and motor activity were assessed in hyperammonemic and BDL rats given ibuprofen as an anti-inflammatory agent. RESULTS: Chronic moderate hyperammonemia or BDL activated the microglia, especially in cerebellum; increased inducible nitric oxide synthase, interleukin-1beta, and prostaglandin E2 levels; and impaired cognitive and motor function, compared with controls. Ibuprofen reduced microglial activation and restored cognitive and motor functions in the hyperammonemic and BDL rats. CONCLUSIONS: Chronic hyperammonemia is sufficient to induce microglial activation and neuroinflammation; these contribute to the cognitive and motor alterations that occur during hepatic encephalopathy.
Assuntos
Comportamento Animal , Transtornos Cognitivos/etiologia , Cognição , Encefalopatia Hepática/etiologia , Hiperamonemia/complicações , Inflamação/etiologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Comportamento Animal/efeitos dos fármacos , Ductos Biliares/cirurgia , Encéfalo/imunologia , Encéfalo/patologia , Movimento Celular , Cognição/efeitos dos fármacos , Transtornos Cognitivos/imunologia , Transtornos Cognitivos/patologia , Transtornos Cognitivos/prevenção & controle , Transtornos Cognitivos/psicologia , Modelos Animais de Doenças , Encefalopatia Hepática/imunologia , Encefalopatia Hepática/patologia , Encefalopatia Hepática/prevenção & controle , Encefalopatia Hepática/psicologia , Hiperamonemia/tratamento farmacológico , Hiperamonemia/imunologia , Hiperamonemia/patologia , Hiperamonemia/psicologia , Ibuprofeno/farmacologia , Inflamação/tratamento farmacológico , Inflamação/imunologia , Inflamação/patologia , Inflamação/psicologia , Mediadores da Inflamação/metabolismo , Aprendizagem , Ligadura , Masculino , Microglia/imunologia , Microglia/patologia , Atividade Motora , Compostos de Amônio Quaternário , Ratos , Ratos WistarRESUMO
Food addiction (FA) is characterized by behavioral and neurochemical changes linked to loss of food intake control. Gut microbiota may influence appetite and food intake via endocrine and neural routes. The gut microbiota is known to impact homeostatic energy mechanisms, but its role in regulating the reward system is less certain. We show that the administration of Bacteroides uniformis CECT 7771 (B. uniformis) in a rat FA model impacts on the brain reward response, ameliorating binge eating and decreasing anxiety-like behavior. These effects are mediated, at least in part, by changes in the levels of dopamine, serotonin, and noradrenaline in the nucleus accumbens and in the expression of dopamine D1 and D2 receptors in the prefrontal cortex and intestine. B. uniformis reverses the fasting-induced microbiota changes and increases the abundance of species linked to healthy metabolotypes. Our data indicate that microbiota-based interventions might help to control compulsive overeating by modulating the reward response.