Fluoxetine-induced hepatic lipid accumulation is linked to elevated serotonin production.

Fluoxetine, a commonly prescribed selective serotonin reuptake inhibitor antidepressant, has been shown to increase hepatic lipid accumulation, a key factor in the development of nonalcoholic fatty liver disease. Interestingly, fluoxetine has also been reported to increase peripheral serotonin synthesis. As emerging evidence suggests that serotonin may be involved in the development of nonalcoholic fatty liver disease, we sought to determine if fluoxetine-induced hepatic lipid accumulation is mediated via altered serotonin production. Fluoxetine treatment increased lipid accumulation in association with increased mRNA expression of tryptophan hydroxylase 1 (Tph1, serotonin biosynthetic enzyme) and intracellular serotonin content. Serotonin alone had a similar effect to increase lipid accumulation. Moreover, blocking serotonin synthesis reversed the fluoxetine-induced increases in lipid accumulation. Collectively, these data suggest that fluoxetine-induced lipid accumulation can be mediated, in part, by elevated serotonin production. These results suggest a potential therapeutic target to ameliorate the adverse metabolic effects of fluoxetine exposure.

Theobromine ameliorates nonalcoholic fatty liver disease by regulating hepatic lipid metabolism via mTOR signaling pathway in vivo and in vitro.

Theobromine, a methylxanthine present in cocoa, has been shown to possess many beneficial pharmacological properties such as anti-oxidative stress, anti-inflammatory property, and anti-microbial activity. In this study, we investigated the effects of theobromine on nonalcoholic fatty liver disease (NAFLD) and the possible underlying mechanisms in vivo and in vitro. The results showed that theobromine reduced body weight and fat mass and improved dyslipidemia. Theobromine mitigated liver injury and significantly reduced hepatic triglyceride level in mice with obesity. Histological examinations also showed hepatic steatosis was alleviated after theobromine treatment. Furthermore, theobromine reversed the elevated mRNA and protein expression of SREBP-1c, FASN, CD36, FABP4, and the suppressed expression of PPARα and CPT1a in the liver of mice with obesity, which were responsible for lipogenesis, fatty acid uptake, and fatty acid oxidation respectively. In vitro, theobromine also downregulated SREBP-1c, FASN, CD36, FABP4 and upregulated PPARα and CPT1a mRNA and protein levels in hepatocytes in a dose-dependent manner, while these changes were reversed by L-leucine, a mammalian target of rapamycin (mTOR) agonist. The present study demonstrated that theobromine improved NAFLD by inhibiting lipogenesis and fatty acid uptake and promoting fatty acid oxidation in the liver and hepatocytes, which might be associated with its suppression of mTOR signaling pathway. Novelty: Theobromine protects against high-fat diet - induced NAFLD. Theobromine inhibits lipogenesis and fatty acid uptake and promotes fatty acid oxidation in the liver and hepatocytes via inhibiting mTOR signaling pathway.

Fructosa, un factor clave modificable en la patogenia del síndrome metabólico, la esteatosis hepática y la obesidad / Fructose, a modifiable key factor in the pathogenic basis of metabolic syndrome, NAFLD and obesity / Frutose, um fator chave modificável na patogênese da síndrome metabólica, esteatose hepática e obesidade

Resumen: En esta revisión se resume el rol específico que el exceso de consumo de fructosa más allá de sus calorías puede tener en el desarrollo del síndrome metabólico, la esteatosis hepática no alcohólica y su asociación con la obesidad. Se desglosan los efectos de la fructosa (en comparación con la glucosa) en la esteatosis hepática, lo que genera la insulino-resistencia y la hipertrigliceridemia. Por su metabolismo hepático mayoritario y la falta de regulación, los flujos altos de fructosa consumen ATP generando ácido úrico, producen metabolitos tóxicos, como ceramidas y metilglioxal, y activan la síntesis de lípidos. Además, se analizan los efectos en el tejido adiposo, la activación del cortisol y las hormonas involucradas en el control de la saciedad, todas las cuales se ven afectadas por el consumo de fructosa. La insulino-resistencia hepática inicial se complica con insulino-resistencia sistémica, que genera leptino-resistencia y un ciclo de hiperfagia. Estos resultados subrayan la necesidad de intervenciones clínicas y educativas dentro de la población para regular o reducir el consumo de fructosa, especialmente en niños y adolescentes, sus principales consumidores.

Summary: This review summarizes the specific role that excess fructose consumption (beyond its calories) may have in the development of MetS, NAFLD and its association with obesity. The effects of fructose (compared to glucose) on hepatic steatosis are discussed as well as their consequence: insulin resistance and hypertriglyceridemia. Unlike glucose, more than 80% ingested fructose stays in the liver, and due to lack of fine metabolic regulation, high fructose flows consume ATP generating uric acid, produce toxic metabolites such as ceramides and methylglyoxal and activate lipid synthesis. In addition, the study analyzes the effects of fructose on adipose tissue, cortisol activation and hormones involved in satiety control, all of which are affected by fructose consumption. The initial hepatic insulin resistance is complicated by systemic insulin resistance, which generates leptin resistance and a hyperphagia cycle. These results underscore the need for clinical and educational interventions within the population to regulate / reduce fructose consumption, especially in children and adolescents, their main consumers.

Resumo: No momento vivemos uma pandemia causada pelo vírus SARS-CoV-2, COVID-19, sendo o mais recomendado ficar em casa para reduzir o contágio e que este seja reduzido ao mínimo possível. No século 21, a tecnologia está mais presente do que nunca e faz parte do nosso dia a dia. Tendo em vista que há significativo abuso da mesma, principalmente por adolescentes, na nossa perspectiva que promove o movimento e a redução do comportamento sedentário, propomos o uso de videogames ativos em substituição aos videogames convencionais. Para isso, fizemos uma revisão dos principais benefícios que estas podem trazer, tanto para a população mais jovem como para os idosos. Esta última faixa etária é uma das mais afetadas pela pandemia e, portanto, há uma forte recomendação para que fiquem em casa. No entanto, é recomendável usá-lo com responsabilidade e não investir tempo excessivo que possa causar danos.

Identification, expression analysis, and the regulating function on C/EBPs of KLF10 in Dalian purple sea urchin, Strongylocentrotus nudus.

Accumulating evidence indicates that Krüppel-like factors (KLFs) play important roles in fat biology via the regulation of CCAAT/enhancer binding proteins (C/EBPs). However, KLFs and C/EBPs have not been identified from Strongylocentrotus nudus, and their roles in this species are not clear. In this study, the full-length cDNA of S. nudus KLF10 (SnKLF10) and three cDNA fragments of S. nudus C/EBPs (SnC/EBPs) were obtained. Examination of tissue distribution and expression patterns during gonadal development implied that SnKLF10 and SnC/EBPs play important roles in gonadal lipogenesis. The presence of transcription factor-binding sites (TFBSs) for KLFs in SnC/EBPs, and the results of an over-expression assay, revealed that SnKLF10 negatively regulates the transcription of SnC/EBPs. In addition, the core promoter regions of SnC/EBPs were determined, and multiple TFBSs for transcription factor (TFs) were identified, which are potential regulators of SnC/EBP transcription. Taken together, these results suggest that SnC/EBP genes are potential targets of SnKLF10, and that SnKLF10 plays a role in lipogenesis by repressing the transcription of SnC/EBPs. These findings provide information for further studies of KLF10 in invertebrates and provide new insight into the regulatory mechanisms of C/EBP transcription.

High carbohydrate diet induces nonalcoholic steato-hepatitis (NASH) in a desert gerbil.

A high intake of sugars has been linked to diet-induced health problems. The aim of this study was to assess whether the long-term consumption of a high-carbohydrate diet (HCD) would cause the hepatic histopathological and metabolic abnormalities that characterize nonalcoholic steatohepatitis (NASH) in a desert gerbil, Gerbillus gerbillus. Compared to natural diet, HCD leads to several metabolic disorders including adiposity, dyslipidemia, insulin resistance, ectopic fat deposition in the liver, which were associated with higher levels of transcripts of genes involved with fat synthesis, endoplasmic reticulum (ER) stress, and fibrosis. In the same way, the experimented animals showed enhanced oxidative stress. Taken together, these results demonstrate that HCD consumption in gerbils induces metabolic disorders and damaged liver, which are key contributors to NASH development. These results suggest that this rodent represents a valuable natural model for human diet-induced metabolic disorders and nonalcoholic fatty liver disease (NAFLD).

Effect of time of chronic treatment with fluoride in mice with previously induced Non-Alcoholic Fatty Liver Disease (NAFLD) / Efeito do tempo de tratamento crônico com fluoreto em camundongos com Doença Hepática Gordurosa Não Alcoólica (DHGNA) induzida previamente

O primeiro estudo avaliou o efeito da duração do tratamento crônico com fluoreto (F) em camundongos com doença hepática gordurosa não alcoólica (DHGNA) previamente induzida por dieta hiperlipídica, sobre o perfil lipídico, gotículas lipídicas e triglicerídeos (TG) no fígado, em comparação com os animais alimentados com a dieta normocalórica. Camundongos Swiss machos receberam dieta hiperlipídica por 30 dias para a indução da DHGNA, enquanto os controles receberam dieta normocalórica. Em seguida, cada um destes grupos receberam água contendo 0 ou 50 mg/L F durante 10, 20 ou 30 dias, no primeiro estudo.Os animais foram sacrificados, o sangue foi coletado para análise de F e perfil lipídico e fígado foi coletado para análise de inclusão lipídica, TG e F. Quando os animais foram tratados com dieta normocalórica e F durante 10 e 20 dias, foi observada uma melhoria significativa em muitos parâmetros relacionados com o perfil lipídico, além de uma redução de inclusão lipídica em animais tratados por 20 dias. O tratamento durante 30 dias aumentou o colesterol total e lipoproteína de alta densidade (HDL). Quanto à dieta hiperlipídica, o tratamento com F durante 10 dias não causou quaisquer alterações, enquanto o tratamento durante 20 dias melhorou os parâmetros analisados (redução do colesterol total e lipoproteínas de baixa densidade (LDL)). No entanto, o tratamento por 30 dias apenas diminuiu o HDL. Além disso, a dieta hiperlipídica aumentou a acumulação de F no organismo. Após a realização do primeiro estudo conduzimos o segundo estudo, o qual foi empregado o método de ressonância magnética nuclear (RMN) para investigar a influência do F na de novo lipogênese. Camundongos Swiss machos receberam dieta hiperlipídica por 30 dias para a indução da DHGNA, enquanto os controles receberam dieta normocalórica. Em seguida, cada um destes grupos receberam água contendo 0 ou 50 mg/L F durante 20 dias. Três dias antes da eutanásia, os animais receberam óxido de deutério (2H2O) por sonda esofágica, para obter um enriquecimento da água corporal (cerca de 3%). Os animais foram eutanasiados e coletou-se o sangue para análise de F e o fígado foi coletado para análise de F e de novo lipogêneses. De novo lipogênese foi significativamente menor quando se utilizou a dieta hiperlipídica, em comparação com a dieta normocalórica. Além disso, a administração F tendeu a diminuir a de novo lipogênese quando utilizada a dieta normocalórica. Os nossos dados indicam que F interfere no metabolismo de lipídios e tem uma ação diferente, dependendo do tempo de exposição e do tipo de dieta administrada. Além disso, F não altera de novo lipogênese em animais com DHGNA instalada, mas tende a reduzir, quando os animais são tratados com dieta normocalórica.(AU)

The first study evaluated the effect of duration of chronic treatment with fluoride (F) in mice with nonalcoholic fat liver disease (NAFLD) previously induced by hyperlipidic diet on the lipid profile, lipid droplets and triglycerides (TG) in liver, in comparison with animals fed normocaloric diet. Male Swiss mice received hyperlipidic diet for 30 days for induction of NAFLD, while controls received normocaloric diet. Then each of these groups received water containing 0 or 50mg/L F for 10, 20 or 30 days. The animals were euthanized, blood was collected for analysis of F and lipid profile and liver was collected for lipid droplets, TG and F analysis. When the animals were treated with normocaloric diet and F for 10 and 20 days, a significant improvement in many parameters related to lipid metabolism was observed, in addition to a reduction in lipid droplets in animals treated for 20 days. Treatment for 30 days increased total cholesterol and high density lipoprotein (HDL). As for the hyperlipidic diet, treatment with F for 10 days did not cause any alterations, while treatment for 20 days improved the parameters analyzed (reduced total cholesterol and low density lipoprotein (LDL)). However, treatment for 30 days only decreased HDL. Moreover, hyperlipidic diet increased F accumulation in the body. After the first study we conducted the second study, which employed nuclear magnetic resonance (NMR) to investigate the influence of F on de novo lipogenesis. Male Swiss mice received hyperlipidic diet for 30 days for induction of NAFLD, while controls received normocaloric diet. Then each of these groups received water containing 0 or 50mg/L F for 20 days. Three days prior to euthanasia, the animals received deuterium oxide (2H2O) by gavage to obtain an enrichment of body water (around 3%). The animals were euthanized, blood was collected for F analysis and liver was collected for F analysis and de novo lipogenesis analysis. De novo lipogenesis was significantly lower when the hyperlipidic diet was used, in comparison with the normocaloric diet. In addition, F administration tended to decrease de novo lipogenesis when the normocaloric diet was used. Our data indicate that F interferes in lipid metabolism and has a different action depending on the exposure time and type of diet administered. Moreover, F does not alter de novo Lipogenesis in animals with installed NAFLD, but tends to reduce it when animals are treated with the normocaloric diet.(AU)

Combining metformin therapy with caloric restriction for the management of type 2 diabetes and nonalcoholic fatty liver disease in obese rats.

Weight loss is recommended for patients with nonalcoholic fatty liver disease (NAFLD), while metformin may lower liver enzymes in type 2 diabetics. Yet, the efficacy of the combination of weight loss and metformin in the treatment of NAFLD is unclear. We assessed the effects of metformin, caloric restriction, and their combination on NAFLD in diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats. Male OLETF rats (age 20 weeks; n = 6-8 per group) were fed ad libitum (AL), given metformin (300 mg·kg(-1)·day(-1); Met), calorically restricted (70% of AL; CR), or calorically restricted and given metformin (CR+Met) for 12 weeks. Met lowered adiposity compared with AL but not to the same magnitude as CR or CR+Met (p < 0.05). Although only CR improved fasting insulin and glucose, the combination of CR+Met was needed to improve post-challenge glucose tolerance. All treatments lowered hepatic triglycerides, but further improvements were observed in the CR groups (p < 0.05, Met vs. CR or CR+Met) and a further reduction in serum alanine aminotransferases was observed in CR+Met rats. CR lowered markers of hepatic de novo lipogenesis (fatty acid synthase, acetyl-CoA carboxylase (ACC), and stearoyl-CoA desaturase-1 (SCD-1)) and increased hepatic mitochondrial activity (palmitate oxidation and ß-hydroxyacyl CoA dehydrogenase (ß-HAD) activity). Changes were enhanced in the CR+Met group for ACC, SCD-1, ß-HAD, and the mitophagy marker BNIP3. Met decreased total hepatic mTOR content and inhibited mTOR complex 1, which may have contributed to Met-induced reductions in de novo lipogenesis. These findings in the OLETF rat suggest that the combination of caloric restriction and metformin may provide a more optimal approach than either treatment alone in the management of type 2 diabetes and NAFLD.

DHEA and non-alcoholic fat liver disease: increased gene expression of peroxisome proliferation-activated receptor γ (PPARγ) and fatty acid synthase (FAS) / DHEA e doença gordurosa hepática não-alcoólica: aumento na expressão gênica do peroxisome proliferation-activated receptor γ (PPARγ) e ácido graxo sintase (FAS)

Dehydroespiandrosterone (DHEA) is associated with improvements in chronic degenerative diseases, including obesity, insulin resistance, and cardiovascular diseases. Nevertheless, it is observed an increase in its concentration in individuals with liver lipid infiltration, but it is not precise if this condition emerges as a cause or a consequence. In this way, we aimed to identify gene expression alterations in lipid and glucose liver metabolism markers, as well as oxidative stress markers. For this purpose, male Wistar rats, 12-14 months old were treated with subcutaneous injections of DHEA (only dose of 10 mg kg-1); and after 7 days, hepatic gene expression by PCR real time were performed for the following genes: G6Pase, PEPCK, FAS, PPARγ, malic enzyme, ChREBP, LXR, catalase, GPx, iNOS, NADPH oxidase subunits and PCNA. We observed a tendency of reduction in G6Pase gene expression in treated group (p = 0.08). In addition, it was identified an increase in liver PPARγ and FAS gene expressions, two markers of increased activity of lipogenic pathway. We also observed an increase in iNOS gene expression, a known inductor of systemic and hepatic insulin resistance. In conclusion, our data indicates that the treatment with DHEA can be associated with the development of liver lipid infiltration and hepatic insulin resistance.

A deidroepiandrosterona (DHEA) encontra-se associada a melhorias em quadros de obesidade, resistência à insulina e doenças cardiovasculares. Porém, observa-se um aumento na sua concentração em indivíduos portadores de infiltração lipídica hepática, mas sem saber precisar se o mesmo surge como causa ou consequência. Assim, objetivamos identificar alterações na expressão gênica hepática de marcadores relacionados ao metabolismo lipídico e glicídico e de estresse oxidativo. Para tanto, ratos machos com 12-14 meses de idade foram tratados com injeção subcutânea de DHEA (dose única 10 mg kg-1), e após 7 dias foram feitas análises da expressão gênica hepática por PCR em tempo real das seguintes proteínas: G6Pase, PEPCK, FAS, PPARγ, enzima málica, ChREBP, LXR, catalase, GPx, iNOS, subunidades da NADPHoxidase e PCNA. Observamos uma tendência à redução da expressão gênica da G6Pase no grupo tratado (p = 0,08). Também identificamos um aumento na expressão gênica hepática do PPARγ e FAS, dois indicadores de aumento da atividade das vias de lipogênese. Observamos um aumento na expressão gênica da iNOS, um conhecido agente indutor de resistência insulina sistêmica e hepática. Em conclusão, nossos dados indicam que o tratamento com DHEA pode estar associado com o desenvolvimento de um quadro de infiltração lipídica hepática e resistência à insulina hepática.

O tecido adiposo como órgão endócrino: da teoria à prática: [revisão] / Adipose tissue as an endocrine organ: from theory to practice: [review]

OBJETIVOS Mostrar os avanços na pesquisa sobre o papel fisiológico do tecido adiposo branco, ressaltando o seu papel endócrino em processos inflamatórios, no comportamento alimentar, na sensibilização à insulina e na modulação do processo de aterogênese. Abordar o potencial papel do tecido adiposo como fonte de células-tronco para regeneração de tecidos, com especial ênfase para a adipogênese e suas conseqüências para a geração de obesidade. FONTES DE DADOS: Informações importantes constantes da literatura científica foram compiladas de modo a que esta leitura contenha uma síntese esclarecedora dos aspectos mencionados acima. SÍNTESE DOS DADOS:O tecido adiposo possui, além das suas funções clássicas como principal estoque de energia metabólica, suprindo as necessidades energéticas em períodos de carência mediante a lipólise, a capacidade de sintetizar e secretar vários hormônios, as adipocinas. Estas agem em diversos processos, como o controle da ingestão alimentar (leptina) e o controle da sensibilidade à insulina e de processos inflamatórios (TNF-alfa, IL-6, resistina, visfatina, adiponectina). Além disso, como o tecido adiposo contém também células indiferenciadas, tem a habilidade de gerar novos adipócitos, regenerando o próprio tecido (adipogênese), bem como originar outras células (mioblastos, condroblastos, osteoblastos), fato este que tem grande potencial terapêutico em futuro não muito distante. CONCLUSÃO: Amplia-se o leque de possibilidades funcionais do tecido adiposo. A compreensão dessas potencialidades pode fazer deste tecido o grande aliado no combate de moléstias que atualmente vêm assumindo proporções epidêmicas (obesidade, diabetes melito, hipertensão arterial e arteriosclerose), nas quais o tecido adiposo ainda é tido como um grande vilão.

OBJECTIVES: To describe the advances in research into the physiological role of white adipose tissue, with emphasis on its endocrinal role in inflammatory processes, feeding behavior, insulin sensitization and modulation of the atherogenetic process. To deal with the potential role of adipose tissue as a source of stem cells for regeneration of tissues, with special emphasis on adipogenesis and its consequences for development of obesity. SOURCES: Important information was compiled from the scientific literature in order that this analysis contains an explanatory synthesis of the aspects mentioned above. SUMMARY OF THE FINDINGS In addition to its classical functions as primary metabolic energy store, meeting energy requirements during periods of deprivation by means of lypolisis, adipose tissue also has the capacity to synthesize and secrete a variety of hormones - the adipokines. These are active in a range of processes, such as control of nutritional intake (leptin) and control of sensitivity to insulin and inflammatory processes (TNF-alpha, IL-6, resistin, visfatin, adiponectin). Furthermore, since adipose tissue also contains undifferentiated cells, it has the ability to generate new adipocytes, regenerating its own tissue (adipogenesis), and also the ability to give rise to other cells (myoblasts, chondroblasts, osteoblasts), which has great therapeutic potential in the not-too-distant future. CONCLUSIONS: The range of functional possibilities of adipose tissue has widened. An understanding of these potentials could make this tissue a great ally in the fight against conditions that are currently assuming epidemic proportions (obesity, diabetes mellitus, arterial hypertension and arteriosclerosis) and in which adipose tissue is still seen as the enemy.