Obesity and type 2 diabetes are characterized by subclinical inflammatory process. Changes in composition or modulation of the gut microbiota may play an important role in the obesity-associated ...inflammatory process. In the current study, we evaluated the effects of probiotics (Lactobacillus rhamnosus, L. acidophilus and Bifidobacterium bifidumi) on gut microbiota, changes in permeability, and insulin sensitivity and signaling in high-fat diet and control animals. More importantly, we investigated the effects of these gut modulations on hypothalamic control of food intake, and insulin and leptin signaling. Swiss mice were submitted to a high-fat diet (HFD) with probiotics or pair-feeding for 5 weeks. Metagenome analyses were performed on DNA samples from mouse feces. Blood was drawn to determine levels of glucose, insulin, LPS, cytokines and GLP-1. Liver, muscle, ileum and hypothalamus tissue proteins were analyzed by Western blotting and real-time polymerase chain reaction. In addition, liver and adipose tissues were analyzed using histology and immunohistochemistry. The HFD induced huge alterations in gut microbiota accompanied by increased intestinal permeability, LPS translocation and systemic low-grade inflammation, resulting in decreased glucose tolerance and hyperphagic behavior. All these obesity-related features were reversed by changes in the gut microbiota profile induced by probiotics. Probiotics also induced an improvement in hypothalamic insulin and leptin resistance. Our data demonstrate that the intestinal microbiome is a key modulator of inflammatory and metabolic pathways in both peripheral and central tissues. These findings shed light on probiotics as an important tool to prevent and treat patients with obesity and insulin resistance.
Our understanding of the pathophysiology of the COVID-19 manifestations and evolution has improved over the past 10 months, but the reasons why evolution is more severe in obese and diabetic patients ...are not yet completely understood.
In the present review we discuss the different mechanisms that may contribute to explain the pathophysiology of COVID-19 including viral entrance, direct viral toxicity, endothelial dysfunction, thromboinflammation, dysregulation of the immune response, and the renin-angiotensin-aldosterone system.
We show that the viral infection activates an integrated stress response, including activations of serine kinases such as PKR and PERK, which induce IRS-1 serine phosphorylation and insulin resistance. In parallel, we correlate and show the synergy of the insulin resistance of COVID-19 with this hormonal resistance of obesity and diabetes, which increase the severity of the disease. Finally, we discuss the potential beneficial effects of drugs used to treat insulin resistance and diabetes in patients with COVID-19.
Electrically conductive polymer composites were produced by melt mixing technique using polyester‐based thermoplastic polyurethane (TPU) as matrix and polypyrrole (PPy) or montmorillonite/polypyrrole ...(MMT/PPy) fillers doped with dodecylbenzenesulfonic acid. Composites with different mass concentrations of conductive additives were obtained and characterized, comparing the electrical properties, structure, and morphology of the composites in order to evaluate the effect of conductive filler content and type. The results showed that TPU/MMT/PPy composites have lower percolation threshold and higher electrical conductivity than TPU/PPy. This behavior was attributed to the higher aspect ratio, better dispersion, and greater interaction between nanostructured MMT/PPy and TPU host insulating when compared with neat PPy. In addition, TPU/MMT/PPy composites produced using polyester‐based TPU tend to have better electrical properties than polyether‐based TPU composites due to its higher polarity, increasing the electrical conductivity and reducing the percolation threshold.
The aim of this work was to investigate the effects of glyphosate on the antioxidant system, as well as the neurotoxic effects on the larvae of Rhamdia quelen. A completely randomized design was ...implemented with the eggs of silver catfish distributed in 48 containers with 300 mL of water, which were subdivided randomly into two groups: control and treated with 6.5 mg L of glyphosate. These groups were evaluated at four time points (12 h, 24 h, 48 h, and 72 h), each with six replications. The survival rate of eggs/larvae (%) was evaluated, and samples were collected for antioxidant system analysis (catalase – CAT, glutathione transferase – GST, glutathione reductase – GR, and lipoperoxidation – LPO), and neurotoxic evaluation (cholinesterase – ChE). Throughout the 72 h of experimentation, there was a higher survival rate among the animals treated with glyphosate. The highest value of integrated biomarkers response (IBR = 1.26) was at 12 h, presenting induction of the cholinesterase (ChE) enzyme and GR. At 24 h, the value of IBR was −2.56, with inhibition of ChE and induction of GR. At 48 h, the value was −0.76, with induction of LPO. The lowest value of IBR was at 72 h (−4.65), with induction of GST and inhibition of all other biomarkers. Finally, it was possible to detect an acute effect of glyphosate throughout the early development of R. quelen, with a decrease in the antioxidant system control and neurotoxic effects.
•Effects in larvae of Rhamdia quelen exposed to sublethal doses of glyphosate.•Changes on antioxidant system and neurotoxic effects caused by glyphosate.•Decrease of IBR over the larval development in animals exposed to glyphosate.
The growing demand for energy worldwide and the extensive use of fossil fuels have resulted in severe environmental problems such as air pollution and the accumulation of greenhouse gases in the ...atmosphere. In this scenario, both new energy sources and more efficient energy conversion processes have been deeply studied. Heterogeneous catalysis is currently widely used for hydrogen production due to its higher selectivity and conversion compared to other processes. Although the use of catalysts is fundamental for green chemistry, their production through traditional methods is less environmentally friendly. Nonetheless, in order to obtain more efficient supported metal catalysts, interest in using non-thermal plasma as a pretreatment or synthesis technique is increasing. Thus, the present article aims at summarizing and briefly discussing the relevant research results on this subject, elucidating the advantages and disadvantages of using non-thermal plasmas in the preparation of supported metal catalysts. Aspects such as morphology, the chemical composition of the catalytic surface, crystallographic phases, average size and dispersion of crystallites, specific surface area, and metal–support interaction have been analyzed. The use of plasma-assisted techniques contributes to the synthesis of supported metal catalysts with smaller, more dispersed, and strongly bonded active particles, resulting in higher catalytic activity, conversion rate, selectivity, and durability. In addition, plasma allows the synthesis of supported metal catalysts to be enhanced by reducing the process time, the use of hazardous substances, and the temperature required.
Abstract Introduction: Identifying risk factors for autosomal dominant polycystic kidney disease (ADPKD) progression is important. However, studies that have evaluated this subject using a Brazilian ...sample is sparce. Therefore, the aim of this study was to identify risk factors for renal outcomes and death in a Brazilian cohort of ADPKD patients. Methods: Patients had the first medical appointment between January 2002 and December 2014, and were followed up until December 2019. Associations between clinical and laboratory variables with the primary outcome (sustained decrease of at least 57% in the eGFR from baseline, need for dialysis or renal transplantation) and the secondary outcome (death from any cause) were analyzed using a multiple Cox regression model. Among 80 ADPKD patients, those under 18 years, with glomerular filtration rate <30 mL/min/1.73 m2, and/or those with missing data were excluded. There were 70 patients followed. Results: The factors independently associated with the renal outcomes were total kidney length – adjusted Hazard Ratio (HR) with a 95% confidence interval (95% CI): 1.137 (1.057–1.224), glomerular filtration rate – HR (95% CI): 0.970 (0.949–0.992), and serum uric acid level – HR (95% CI): 1.643 (1.118–2.415). Diabetes mellitus - HR (95% CI): 8.115 (1.985–33.180) and glomerular filtration rate - HR (95% CI): 0.957 (0.919–0.997) were associated with the secondary outcome. Conclusions: These findings corroborate the hypothesis that total kidney length, glomerular filtration rate and serum uric acid level may be important prognostic predictors of ADPKD in a Brazilian cohort, which could help to select patients who require closer follow up.
Resumo Introdução: É importante identificar fatores de risco para progressão da doença renal policística autossômica dominante (DRPAD). Entretanto, são escassos os estudos que avaliam esse assunto utilizando amostra brasileira. Portanto, o objetivo deste estudo foi identificar fatores de risco para desfechos renais e óbito em coorte brasileira de pacientes com DRPAD. Métodos: Os pacientes tiveram o primeiro atendimento médico entre janeiro/2002 e dezembro/2014, sendo acompanhados até dezembro/2019. Associações entre variáveis clínicas e laboratoriais com desfecho primário (redução sustentada de pelo menos 57% na TFGe em relação ao valor basal, necessidade de diálise ou transplante renal) e desfecho secundário (óbito por qualquer causa) foram analisadas pelo modelo de regressão múltipla de Cox. Entre 80 pacientes com DRPAD, foram excluídos aqueles menores de 18 anos, com TFG <30 mL/min/1,73 m2 e/ou aqueles com dados ausentes. Foram acompanhados 70 pacientes. Resultados: Fatores independentemente associados aos desfechos renais foram: comprimento renal total – Razão de Risco (HR) ajustada com intervalo de confiança de 95% (IC 95%): 1,137 (1,057–1,224), taxa de filtração glomerular – HR (IC 95%): 0,970 (0,949–0,992) e nível sérico de ácido úrico - HR (IC 95%): 1,643 (1,118–2,415). Diabetes mellitus – HR (IC 95%): 8,115 (1,985–33,180) e TFG – HR (IC 95%): 0,957 (0,919–0,997) foram associados ao desfecho secundário. Conclusões: Esses achados corroboram a hipótese de que comprimento renal total, TFG e nível sérico de ácido úrico podem ser importantes preditores prognósticos de DRPAD em uma coorte brasileira, o que pode ajudar a selecionar pacientes que necessitam de acompanhamento mais próximo.
Background
Obesity has been linked to gastrointestinal disorders, and the loss of myenteric neurons in the intestine caused by high‐fat diets (HFD) has been attributed to changes in microbiota and ...lipotoxicity. We investigated whether the prebiotic inulin modulates bacterial populations and alleviates neuronal loss in mice fed HFD.
Methods
Swiss mice were fed purified rodent diet or HFD (59% kcal fat), or both diets supplemented with inulin for 17 weeks. Intestinal motility was assessed and a metagenome analysis of the colonic microbiota was performed. The gene expression of inflammatory markers was evaluated, and immunofluorescence was performed for different types of myenteric neurons and glial cells in the distal colon.
Key Results
The HFD caused obesity and delayed colonic motility. The loss of myenteric neurons and glial cells in obese mice affected all of the studied neuronal populations, including neurons positive for myosin‐V, neuronal nitric oxide synthase, vasoactive intestinal peptide, and calretinin. Although obese mice supplemented with inulin exhibited improvements in colonic motility, neuronal, and glial cell loss persisted. The HFD did not altered the expression levels of inflammatory cytokines in the intestine or the prevalence of the major groups in microbiota, but inulin increased the proportion of the genus Akkermansia in the obese mice.
Conclusions and Inferences
In Swiss mice, the HFD‐induced neuronal loss but did not change the major groups in microbiota. This suggests that, despite the increase in the beneficial bacteria, other factors that are directly linked to excess dietary lipid intake affect the enteric nervous system.
A high‐fat diet causes neuronal loss and intestinal dysmotility in the colon of obese Swiss mice, without changes in the major groups of colonic microbiota. These findings reinforce that the lipotoxicity of the diet has a major role in the damage to the enteric nervous system.
In obesity, insulin resistance (IR) and diabetes, there are proteins and hormones that may lead to the discovery of promising biomarkers and treatments for these metabolic disorders. For example, ...these molecules may impair the insulin signaling pathway or provide protection against IR. Thus, identifying proteins that are upregulated in IR states is relevant to the diagnosis and treatment of the associated disorders. It is becoming clear that hepatocyte growth factor (HGF) is an important component of the pathophysiology of IR, with increased levels in most common IR conditions, including obesity. HGF has a role in the metabolic flux of glucose in different insulin sensitive cell types; plays a key role in β-cell homeostasis; and is capable of modulating the inflammatory response. In this review, we discuss how, and to what extent HGF contributes to IR and diabetes pathophysiology, as well as its role in cancer which is more prevalent in obesity and diabetes. Based on the current literature and knowledge, it is clear that HGF plays a central role in these metabolic disorders. Thus, HGF levels could be employed as a biomarker for disease status/progression, and HGF/c-Met signaling pathway modulators could effectively regulate IR and treat diabetes.
Display omitted
Intestinal helminths are prevalent in individuals who live in rural areas of developing countries, where obesity, type 2 diabetes, and metabolic syndrome are rare. In the present ...study, we analyzed the modulation of the gut microbiota in mice infected with the helminth Strongyloides venezuelensis, and fed either a standard rodent chow diet or high-fat diet (HFD). To investigate the effects of the microbiota modulation on the metabolism, we analyzed the expression of tight-junction proteins present in the gut epithelium, inflammatory markers in the serum and tissue and quantified glucose tolerance and insulin sensitivity and resistance. Additionally, the levels of lipids related to inflammation were evaluated in the feces and serum. Our results show that infection with Strongyloides venezuelensis results in a modification of the gut microbiota, most notably by increasing Lactobacillus spp. These modifications in the microbiota alter the host metabolism by increasing the levels of anti-inflammatory cytokines, switching macrophages from a M1 to M2 pattern in the adipose tissue, increasing the expression of tight junction proteins in the intestinal cells (thereby reducing the permeability) and decreasing LPS in the serum. Taken together, these changes correlate with improved insulin signaling and sensitivity, which could also be achieved with HFD mice treated with probiotics. Additionally, helminth infected mice produce higher levels of oleic acid, which participates in anti-inflammatory pathways. These results suggest that modulation of the microbiota by helminth infection or probiotic treatment causes a reduction in subclinical inflammation, which has a positive effect on the glucose metabolism of the host.
This study investigated the effects of feeding paraprobiotics obtained by six processes heat, ultrasound, high pH, low pH, irradiation and supercritical carbon dioxide (CO
2
) on biochemical ...parameters and intestinal microbiota of Wistar male rats. Daily administration of paraprobiotics did not affect (p ≥ 0.05) the food intake, body weight, glucose and triglycerides levels, expression of antioxidant enzymes or thermal shock proteins in comparison to the control. Bifidobacterium lactis inactivated by irradiation and supercritical CO
2
decreased the total cholesterol levels in serum (p < 0.05). Bifidobacterium lactis inactivated by supercritical CO
2
increased the albumin and creatinine levels, while decreased the HDL-cholesterol levels (p < 0.05). Clostridiales (45.6-56%), Bacteroidales (31.9-44.2%) and Lactobacillales (3.9-7.8%) corresponded to the major orders in paraprobiotic groups. The properties of paraprobiotics are dependent on the method of inactivation, the intensity of the method employed and on the strain used.
PDF
