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We studied the effect of cotadutide, a dual agonist glucagon-like peptide 1 (GLP1)/Glucagon, on interscapular brown adipose tissue (iBAT) remodeling and thermogenesis of obese mice. Twelve-week-old male C57BL/6 mice were fed a control diet (C group, n = 20) or a high-fat diet (HF group, n = 20) for ten weeks. Then, animals were redivided, adding cotadutide treatment: C, CC, HF, and HFC for four additional weeks. The multilocular brown adipocyte structure showed fat conversion (whitening), hypertrophy, and structural disarray in the HF group, which was reverted in cotadutide-treated animals. Cotadutide enhances the body temperature, thermogenesis, and sympathetic innervation (peroxisome proliferator-activated receptor-α, ß3 adrenergic receptor, interleukin 6, and uncoupled protein 1), reduces pro-inflammatory markers (disintegrin and metallopeptidase domain, morphogenetic protein 8a, and neuregulin 4), and improves angiogenesis (vascular endothelial growth factor A, and perlecan). In addition, cotadutide enhances lipolysis (perilipin and cell death-inducing DNA fragmentation factor α), mitochondrial biogenesis (nuclear respiratory factor 1, transcription factor A mitochondrial, mitochondrial dynamin-like GTPase, and peroxisome proliferator-activated receptor gamma coactivator 1α), and mitochondrial fusion/fission (dynamin-related protein 1, mitochondrial fission protein 1, and parkin RBR E3 ubiquitin protein ligase). Cotadutide reduces endoplasmic reticulum stress (activating transcription factor 4, C/EBP homologous protein, and growth arrest and DNA-damage inducible), and extracellular matrix markers (lysyl oxidase, collagen type I α1, collagen type VI α3, matrix metallopeptidases 2 and 9, and hyaluronan synthases 1 and 2). In conclusion, the experimental evidence is compelling in demonstrating cotadutide's thermogenic effect on obese mice's iBAT, contributing to unraveling its action mechanisms and the possible translational benefits.

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Semaglutide (GLP-1 agonist) was approved for treating obesity. Although the effects on weight loss and metabolism are known, the responses of adipocytes to semaglutide are yet limited. C57BL/6 male mice (n = 20/group) were fed a control diet (C) or a high-fat (HF) diet for 16 weeks and then separated into four groups (n = 10/group) for an additional four weeks: C, C diet and semaglutide, HF, and HF diet and semaglutide. Epididymal white adipose tissue (eWAT) and subcutaneous white adipose tissue (sWAT) fat pads were studied with biochemistry, immunohistochemistry/fluorescence, stereology, and reverse transcription-quantitative polymerase chain reaction. In obese mice, semaglutide reduced the fat pad masses (eWAT, -55%; sWAT, -40%), plasmatic cytokines, and proinflammatory gene expressions: tumor necrosis factor-alpha (-60%); interleukin (IL)-6 (-55%); IL-1 beta (-40%); monocyte chemoattractant protein-1 (-90%); and leptin (-80%). Semaglutide also lessened endoplasmic reticulum (ER) stress genes of activating transcription factor-4 (-85%), CCAAT enhancer-binding protein homologous protein (-55%), and growth arrest and DNA damage-inducible gene 45 (-45%). The obese mice's adipocyte hypertrophy and macrophage infiltration were equally reduced by semaglutide. Semaglutide enhanced multiloculation and uncoupled protein 1 (UCP1) labeling in obese mice: peroxisome proliferator-activated receptor-alpha (+560%) and gamma (+150%), fibronectin type III domain-containing protein 5 (+215%), peroxisome proliferator-activated receptor-alpha coactivator (+110%), nuclear respiratory factor 1 (+260%), and mitochondrial transcription factor A (+120%). Semaglutide also increased thermogenetic gene expressions for the browning phenotype maintenance: beta-3 adrenergic receptor (+520%), PR domain containing 16 (+90%), and Ucp1 (+110%). In conclusion, semaglutide showed significant beneficial effects beyond weight loss, directly on fat pads and adipocytes of obese mice, remarkably anti-inflammatory, and reduced adipocyte size and ER stress. Besides, semaglutide activated adipocyte browning, improving UCP1, mitochondrial biogenesis, and thermogenic marker expressions help weight loss.

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Abstract Objective: To discuss the recent literature on paternal obesity, focusing on the possible mechanisms of transmission of the phenotypes from the father to the children. Sources: A non-systematic review in the PubMed database found few publications in which paternal obesity was implicated in the adverse transmission of characteristics to offspring. Specific articles on epigenetics were also evaluated. As the subject is recent and still controversial, all articles were considered regardless of year of publication. Summary of findings: Studies in humans and animals have established that paternal obesity impairs their hormones, metabolism, and sperm function, which can be transmitted to their offspring. In humans, paternal obesity results in insulin resistance/type 2 diabetes and increased levels of cortisol in umbilical cord blood, which increases the risk factors for cardiovascular disease. Notably, there is an association between body fat in parents and the prevalence of obesity in their daughters. In animals, paternal obesity led to offspring alterations on glucose-insulin homeostasis, hepatic lipogenesis, hypothalamus/feeding behavior, kidney of the offspring; it also impairs the reproductive potential of male offspring with sperm oxidative stress and mitochondrial dysfunction. An explanation for these observations (human and animal) is epigenetics, considered the primary tool for the transmission of phenotypes from the father to offspring, such as DNA methylation, histone modifications, and non-coding RNA. Conclusions: Paternal obesity can induce programmed phenotypes in offspring through epigenetics. Therefore, it can be considered a public health problem, affecting the children's future life.

Resumo Objetivo: Discutir a literatura recente sobre obesidade paterna, focalizando os possíveis mecanismos de transmissão dos fenótipos do pai para os filhos. Fontes: Uma revisão não-sistemática no banco de dados PubMed encontrou poucas publicações com obesidade paterna implicada com a transmissão adversa das características à prole. Artigos específicos sobre epigenética também foram avaliados. Como o assunto é recente e ainda controverso, todos os trabalhos foram considerados independentemente do ano de publicação. Resumo dos achados: Estudos em seres humanos e animais estabeleceram que a obesidade do pai prejudica seus hormônios, metabolismo e função espermática, que pode ser transmitida à prole. Em humanos, a obesidade paterna resulta em resistência à insulina / diabetes tipo 2 e aumento do nível de cortisol no sangue do cordão umbilical, que aumenta os fatores de risco para doença cardiovascular. Notavelmente, existe associação entre a gordura corporal nos pais e a prevalência de obesidade em suas filhas. Em animais, pais obesos condicionam, na prole, a homeostase glicose-insulina, lipogênese hepática, hipotálamo / comportamento alimentar, rim, prejudicam o potencial reprodutivo da prole masculina com estresse oxidativo espermático e disfunção mitocondrial. Uma explicação para estas observações (humanos e animais) é a epigenética, considerada a ferramenta básica para a transmissão de fenótipos do pai à prole, como a metilação do DNA, modificações nas histonas, e RNA não codificante. Conclusões: A obesidade paterna pode induzir fenótipos programados na prole através da epigenética. Portanto, a obesidade paterna pode ser considerada um problema de saúde pública, afetando a vida futura das crianças.

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OBJECTIVE: To discuss the recent literature on paternal obesity, focusing on the possible mechanisms of transmission of the phenotypes from the father to the children. SOURCES: A non-systematic review in the PubMed database found few publications in which paternal obesity was implicated in the adverse transmission of characteristics to offspring. Specific articles on epigenetics were also evaluated. As the subject is recent and still controversial, all articles were considered regardless of year of publication. SUMMARY OF FINDINGS: Studies in humans and animals have established that paternal obesity impairs their hormones, metabolism, and sperm function, which can be transmitted to their offspring. In humans, paternal obesity results in insulin resistance/type 2 diabetes and increased levels of cortisol in umbilical cord blood, which increases the risk factors for cardiovascular disease. Notably, there is an association between body fat in parents and the prevalence of obesity in their daughters. In animals, paternal obesity led to offspring alterations on glucose-insulin homeostasis, hepatic lipogenesis, hypothalamus/feeding behavior, kidney of the offspring; it also impairs the reproductive potential of male offspring with sperm oxidative stress and mitochondrial dysfunction. An explanation for these observations (human and animal) is epigenetics, considered the primary tool for the transmission of phenotypes from the father to offspring, such as DNA methylation, histone modifications, and non-coding RNA. CONCLUSIONS: Paternal obesity can induce programmed phenotypes in offspring through epigenetics. Therefore, it can be considered a public health problem, affecting the children's future life.

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The brain is very sensitive to metabolic dysfunctions induced by diets high in saturated fatty acids, leading to neuroinflammation. The liraglutide has been found to have neuroprotective effects. However, its neuroprotective action in a model of palmitate-induced neuroinflammation had not yet been evaluated. Mice were intracerebroventricular (ICV) infused with palmitate and received subcutaneous liraglutide. The hippocampal dentate gyrus and CA1 regions were analyzed (morphology and inflammation-related proteins in microglia and astrocyte by confocal microscopy). Also, a real-time PCR was performed to measure the levels of tumor necrosis factor (TNF) alpha and interleukin (IL) 6. Palmitate ICV infusion resulted in pronounced inflammation response in the hippocampus, reactive microgliosis, and astrogliosis, with hypertrophied IBA1 immunoreactive microglia, increased microglial density with ameboid shape, decreased in the number of branches and junctions and increased the major histocompatibility complex (MHC) II expression. Also, we observed in the hippocampus of ICV palmitate infused mice an elevation in the pro-inflammatory cytokine levels TNFalpha and IL6. Liraglutide induced the neuroprotective microglial phenotype, characterized by an increased microglia complexity (enlarged Feret's diameter), an improved number of both cell junctions and processes, and lower circularity, accompanied by a significant reduction in TNFalpha and IL6 expressions. The study provides evidence that liraglutide may be a suitable treatment against the palmitate-induced neuroinflammation, which it is characterized by the reactive microgliosis and astrogliosis, as well as increased pro-inflammatory cytokines, which has been described as one of the primary causes of several pathologies of the central nervous system.

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Fructose-rich caloric sweeteners induce adverse changes in the metabolism of humans. The study evaluated the effects of high-intensity interval training (HIIT) on a fructose feeding model, focusing on the liver, white adipose tissue (WAT), skeletal muscle, and their interplay. Male C57BL/6 mice were fed for 18 wk one of the following diets: control (C; 5% of total energy from fructose) or fructose (F; 55% of total energy from fructose). In the 10th week, for an additional 8-wk period, the groups were divided into nontrained (NT) or HIIT groups, totaling four groups: C-NT, C-HIIT, F-NT, and F-HIIT. At the end of the experiment, fructose consumption in the F-NT group led to a high systolic blood pressure, high plasma triglycerides, insulin resistance with glucose intolerance, and lower insulin sensitivity. We also observed liver steatosis, adipocyte hypertrophy, and diminished gene expressions of peroxisome proliferator-activated receptor-γ coactivator 1-α and fibronectin type III domain containing 5 (FNDC5; irisin) in this F-NT group. These results were accompanied by decreased gene expressions of nuclear respiratory factor 1 and mitochondrial transcription factor A (markers of mitochondrial biogenesis), and peroxisome proliferator-activated receptor-α and carnitine palmitoyltransferase 1 (markers of ß-oxidation). HIIT improved all of these data in the C-HIIT and F-HIIT groups. In conclusion, in mice fed a fructose diet, HIIT improved body mass, blood pressure, glucose metabolism, and plasma triglycerides. Liver, WAT, and skeletal muscle were positively modulated by HIIT, indicating HIIT as a coadjutant treatment for diseases affecting these tissues.NEW & NOTEWORTHY We investigated the effects of high-intensity interval training (HIIT) in mice fed a fructose-rich diet and the resulting severe negative effect on the liver, white adipose tissue (WAT), and skeletal muscle, which reduced the expression of fibronectin type III domain containing 5 (FNDC5, irisin) and PGC1α and, consequently, affected markers of mitochondrial biogenesis and ß-oxidation. Because HIIT may block these adverse effects in all of these three tissues, it might be suggested that it functions as a coadjutant treatment in combatting the alterations caused by high-fructose intake.

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AIM: The aim of this study was to investigate the effects of rosuvastatin in a model of diet-induced obesity and non-alcoholic fatty liver disease, with attention to the activation of hepatic stellate cells (HSCs). METHOD: Male C57BL/6 mice received a control diet (C; 10% energy as lipids) or a high-fat diet (HF; 50% energy as lipids) for 12 weeks, followed by 7 weeks of treatment. Group CR received control diet + rosuvastatin; group HFR received high-fat diet + rosuvastatin. RESULTS: The HF group showed higher insulin, total cholesterol, triacylglycerol, and leptin levels than the C group, all of which were significantly diminished by rosuvastatin in the HFR group. The HF group had greater steatosis and activated HSCs than the C group, whereas rosuvastatin diminished the steatosis (less 21%, P < 0.001) and significantly inhibited the activation of the HSCs in the HFR group compared to the HF group. The sterol regulatory element-binding protein-1 and the peroxisome proliferator-activated receptor (PPAR)-γ protein expressions were increased in HF animals and reduced after treatment in the HFR group. By contrast, low PPAR-α and carnitine palmitoyltransferase-1 expressions were found in the HF group, and were restored by rosuvastatin treatment in the HFR group. CONCLUSION: Rosuvastatin mitigated hepatic steatosis by modulating PPAR balance, favoring PPAR-α over PPAR-γ downstream effects. The effects were accompanied by a diminishing of insulin resistance, the anti-inflammatory adipokine profile, and HSC activation, avoiding non-alcoholic fatty liver disease progression and non-alcoholic steatohepatitis onset in this model.

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The study aimed to evaluate the impact of high-intensity interval training (HIIT) on adipose tissue, pancreatic islets and liver in mice fed high-fat diet. C57BL/6 male mice were fed one of two diets: standard chow (Lean group - LE) or a high-fat diet (Obese group ­ OB). After the first 12-weeks, the animals were divided into non-trained (LE-NT and OB-NT), trained groups (LE-T and OB-T), and started the exercise protocol. The HIIT protocol in the trained animals (LE-T and OB-T) compared to their counterparts (LE-NT and OB-NT) led to a reduction in size of the pancreatic islets (LE-T vs. LE-NT -40 %, OB-T vs. OB-NT -22 %) and to an increase in insulin immunodensity in pancreatic islet (LE-T vs. LE-NT +35 %, OB-T vs. OB-NT +31 %). Apart from the above results, in adipose tissue, a decrease of the diameter of adipocytes (LE-T vs. LE-NT -23 %, OB-T vs. OB-NT -12 %), a reduction in adiposity index (LE-T vs. LE-NT -49 %, OB-T vs. OB-NT -24 %) and in the liver, a decrease in the context of hepatic steatosis (LE-T vs. LE-NT -57 %, OB-T vs. OB-NT -77 %). These metabolic changes characterize a benefits performance of the HIIT protocol in swimming. HIIT is able to mitigate the bad effects caused by high-fat diet, even with continued intake of this diet in an animal model. HIIT has the advantage of requiring only a few weekly sessions with short duration in each session. These benefits are important to motivate people who nowadays live with a lack of time condition for these activities.

El objetivo fue evaluar el impacto del entrenamiento con intervalos de alta intensidad (EIAI) sobre el tejido adiposo, el hígado y los islotes pancreáticos en ratones alimentados con dieta alta en grasas. Ratones C57BL/6, machos fueron alimentados con una de dos dietas: dieta estándar (grupo magro - MA) o una dieta alta en grasas (grupo obeso - OB). Después de las primeras 12 semanas, los animales fueron divididos en dos grupos, no entrenados (MA-NE y OB-NE) y grupos entrenados (MA-E y OB-E), y comenzaron el protocolo de ejercicio. El protocolo de IEAI en los animales entrenados (MA-E y OB-E) en comparación con sus contrapartes (MA-NE y OB-NE) condujo a una reducción en el tamaño de los islotes pancreáticos (MA-E vs. MA-NE -40 %, OB-E vs. OB-NE -22 %) y al aumento de la inmunodensidad de insulina en los islotes pancreáticos (MA-E vs. MA-NE +35 %, OB-E vs. OB-NE +31 %). Además, en el tejido adiposo se detectó una disminución del diámetro de los adipocitos (MA-E vs. MA-NE -23 %, OB-E vs. OB-NE -12 %), una reducción en el índice de adiposidad (MA-E vs. MA-NE -49 %, OB-E vs. OB-NE -24 %) y en el hígado una disminución de la esteatosis (MA-E vs. MA-NE -57 %, OB-E vs. OB-NE -77 %). Estos cambios metabólicos caracterizan una actuación beneficiosa del protocolo de EIAI en la natación. El EIAI es capaz de mitigar los efectos negativos causados por la dieta alta en grasas, incluso con la ingesta continuada de esta dieta en el modelo animal. La EIAI tiene la ventaja de requir sólo unas pocas sesiones semanales con corta duración de cada sesión. Estos beneficios son importantes para motivar a la personas en las condiciones de falta de tiempo que tienen en la actualidad.

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The maternal deficiency of vitamin D can act on organogenesis in mice offspring, being a risk factor for chronic diseases in adulthood. This study investigates the effects of maternal deficiency of vitamin D on structural islet remodeling and insulin-signaling pathway in the offspring. We studied male C57Bl/6 offspring at 3-month old (n = 10/group) from mother fed one of the two diets: control diet (C) or vitamin D-restricted diet (VitD-). After weaning, offspring only fed the control diet ad libitum. In the offspring, we studied insulin production, islet remodeling, and islet protein expression of the insulin-signaling pathway (Western blotting, isolated islet, n = 5/group). VitD- offspring showed greater glycemia (P = 0.012), smaller beta-cell mass (P = 0.014), and hypoinsulinemia (P = 0.024) than C offspring. Comparing VitD- offspring with C offspring, we observed lower protein levels in islet of insulin (P = 0.003), insulin receptor substrate-1 (P = 0.025), phosphatidylinositol-3-kinases (P = 0.045), 3-phosphoinositide-dependent protein kinase 1 (P = 0.017), protein kinase B (P = 0.028), with reduced expression of pancreas/duodenum homeobox-1 (PDX-1) (P = 0.016), glucose transporter-2 (P = 0.003), and glucokinase (P = 0.045). The maternal vitamin D-restricted diet modifies the development of the pancreas of the offspring, leading to islet remodeling and altered insulin-signaling pathway. The decrease of PDX-1 is probably significant to the changes in the beta-cell mass and insulin secretion in adulthood.

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OBJECTIVE: The neuroprotective effects of liraglutide (200 µg/kg, twice daily, subcutaneous administration) in the hypothalamic arcuate nucleus (ARC) of diet-induced obese mice were investigated. METHODS: C57BL/6 mice were separated into groups: standard chow treated with vehicle or liraglutide and the respective liraglutide pair-fed group; high-fat diet treated with vehicle or liraglutide and the respective pair-fed group. Body mass (BM) evolution, carbohydrate metabolism, leptin resistance, proteins involved in energetic balance, apoptosis, and microglia in the ARC were studied. RESULTS: Obese animals showed glucose intolerance, resistance to insulin and to anorexigenic effect of leptin, and microgliosis accompanied by elevated Bax/Bcl2 ratio in the ARC. Liraglutide improved the carbohydrate metabolism, BM loss, and the activation of pro-opiomelanocortin (POMC) and cocaine and amphetamine-regulated transcript (CART) in the ARC. The liraglutide enhanced leptin sensitivity and diminished the microgliosis with decrease in Bax/Bcl2 ratio. CONCLUSIONS: Liraglutide activates central anorexigenic pathways, thereby diminishing the energy intake of obese mice and improving the metabolic parameters related to obesity. Liraglutide is a relevant neuroprotective agent, which can decrease the microgliosis and stimulate the anti-apoptotic pathway, a significant effect in the treatment of obesity and its comorbidities. Some benefits of liraglutide are independent of the BM loss, which usually accompanies the drug administration.

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