Neuropsychiatric Symptoms and Microglial Activation in Patients with Alzheimer Disease.

Importance: Neuropsychiatric symptoms are commonly encountered and are highly debilitating in patients with Alzheimer disease. Understanding their underpinnings has implications for identifying biomarkers and treatment for these symptoms. Objective: To evaluate whether glial markers are associated with neuropsychiatric symptoms in individuals across the Alzheimer disease continuum. Design, Setting, and Participants: This cross-sectional study was conducted from January to June 2023, leveraging data from the Translational Biomarkers in Aging and Dementia cohort at McGill University, Canada. Recruitment was based on referrals of individuals from the community or from outpatient clinics. Exclusion criteria included active substance abuse, major surgery, recent head trauma, safety contraindications for positron emission tomography (PET) or magnetic resonance imaging, being currently enrolled in other studies, and having inadequately treated systemic conditions. Main Outcomes and Measures: All individuals underwent assessment for neuropsychiatric symptoms (Neuropsychiatry Inventory Questionnaire [NPI-Q]), and imaging for microglial activation ([11C]PBR28 PET), amyloid-ß ([18F]AZD4694 PET), and tau tangles ([18F]MK6240 PET). Results: Of the 109 participants, 72 (66%) were women and 37 (34%) were men; the median age was 71.8 years (range, 38.0-86.5 years). Overall, 70 had no cognitive impairment and 39 had cognitive impairment (25 mild; 14 Alzheimer disease dementia). Amyloid-ß PET positivity was present in 21 cognitively unimpaired individuals (30%) and in 31 cognitively impaired individuals (79%). The NPI-Q severity score was associated with microglial activation in the frontal, temporal, and parietal cortices (ß = 7.37; 95% CI, 1.34-13.41; P = .01). A leave-one-out approach revealed that irritability was the NPI-Q domain most closely associated with the presence of brain microglial activation (ß = 6.86; 95% CI, 1.77-11.95; P = .008). Furthermore, we found that microglia-associated irritability was associated with study partner burden measured by NPI-Q distress score (ß = 5.72; 95% CI, 0.33-11.10; P = .03). Conclusions and Relevance: In this cross-sectional study of 109 individuals across the AD continuum, microglial activation was associated with and a potential biomarker of neuropsychiatric symptoms in Alzheimer disease. Moreover, our findings suggest that the combination of amyloid-ß- and microglia-targeted therapies could have an impact on relieving these symptoms.

Caveolin-1 influences mitochondrial plasticity and function in hepatic stellate cell activation.

Caveolin-1 (Cav-1) is an integral membrane protein present in all organelles, responsible for regulating and integrating multiple signals as a platform. Mitochondria are extremely adaptable to external cues in chronic liver diseases, and expression of Cav-1 may affect mitochondrial flexibility in hepatic stellate cells (HSCs) activation. We previously demonstrated that exogenous expression of Cav-1 was sufficient to increase some classical markers of activation in HSCs. Here, we aimed to evaluate the influence of exogenous expression and knockdown of Cav-1 on regulating the mitochondrial plasticity, metabolism, endoplasmic reticulum (ER)-mitochondria distance, and lysosomal activity in HSCs. To characterize the mitochondrial, lysosomal morphology, and ER-mitochondria distance, we perform transmission electron microscope analysis. We accessed mitochondria and lysosomal networks and functions through a confocal microscope and flow cytometry. The expression of mitochondrial machinery fusion/fission genes was examined by real-time polymerase chain reaction. Total and mitochondrial cholesterol content was measured using Amplex Red. To define energy metabolism, we used the Oroboros system in the cells. We report that GRX cells with exogenous expression or knockdown of Cav-1 changed mitochondrial morphometric parameters, OXPHOS metabolism, ER-mitochondria distance, lysosomal activity, and may change the activation state of HSC. This study highlights that Cav-1 may modulate mitochondrial function and structural reorganization in HSC activation, being a potential candidate marker for chronic liver diseases and a molecular target for therapeutic intervention.

Functional Recovery Caused by Human Adipose Tissue Mesenchymal Stem Cell-Derived Extracellular Vesicles Administered 24 h after Stroke in Rats.

Ischemic stroke is a major cause of death and disability, intensely demanding innovative and accessible therapeutic strategies. Approaches presenting a prolonged period for therapeutic intervention and new treatment administration routes are promising tools for stroke treatment. Here, we evaluated the potential neuroprotective properties of nasally administered human adipose tissue mesenchymal stem cell (hAT-MSC)-derived extracellular vesicles (EVs) obtained from healthy individuals who underwent liposuction. After a single intranasal EV (200 µg/kg) administered 24 h after a focal permanent ischemic stroke in rats, a higher number of EVs, improvement of the blood-brain barrier, and re-stabilization of vascularization were observed in the recoverable peri-infarct zone, as well as a significant decrease in infarct volume. In addition, EV treatment recovered long-term motor (front paws symmetry) and behavioral impairment (short- and long-term memory and anxiety-like behavior) induced by ischemic stroke. In line with these findings, our work highlights hAT-MSC-derived EVs as a promising therapeutic strategy for stroke.

Ethylmalonic acid impairs bioenergetics by disturbing succinate and glutamate oxidation and induces mitochondrial permeability transition pore opening in rat cerebellum.

Tissue accumulation and high urinary excretion of ethylmalonic acid (EMA) are found in ethylmalonic encephalopathy (EE), an inherited disorder associated with cerebral and cerebellar atrophy whose pathogenesis is poorly established. The in vitro and in vivo effects of EMA on bioenergetics and redox homeostasis were investigated in rat cerebellum. For the in vitro studies, cerebellum preparations were exposed to EMA, whereas intracerebellar injection of EMA was used for the in vivo evaluation. EMA reduced state 3 and uncoupled respiration in vitro in succinate-, glutamate-, and malate-supported mitochondria, whereas decreased state 4 respiration was observed using glutamate and malate. Furthermore, mitochondria permeabilization and succinate supplementation diminished the decrease in state 3 with succinate. EMA also inhibited the activity of KGDH, an enzyme necessary for glutamate oxidation, in a mixed manner and augmented mitochondrial efflux of α-ketoglutarate. ATP levels were markedly reduced by EMA, reflecting a severe bioenergetic disruption. Docking simulations also indicated interactions between EMA and KGDH and a competition with glutamate and succinate for their mitochondrial transporters. In vitro findings also showed that EMA decreased mitochondrial membrane potential and Ca2+ retention capacity, and induced swelling in the presence of Ca2+ , which were prevented by cyclosporine A and ADP and ruthenium red, indicating mitochondrial permeability transition (MPT). Moreover, EMA, at high concentrations, mildly increased ROS levels and altered antioxidant defenses in vitro and in vivo. Our data indicate that EMA-induced impairment of glutamate and succinate oxidation and MPT may contribute to the pathogenesis of the cerebellum abnormalities in EE.

Guanosine Neuroprotection of Presynaptic Mitochondrial Calcium Homeostasis in a Mouse Study with Amyloid-ß Oligomers.

Amyloid-ß oligomers (AßOs) toxicity causes mitochondrial dysfunction, leading to synaptic failure in Alzheimer's disease (AD). Considering presynaptic high energy demand and tight Ca2+ regulation, impairment of mitochondrial function can lead to deteriorated neural activity and cell death. In this study, an AD mouse model induced by ICV (intracerebroventricular) injection of AßOs was used to investigate the toxicity of AßOs on presynaptic function. As a therapeutic approach, GUO (guanosine) was given by oral route to evaluate the neuroprotective effects on this AD model. Following 24 h and 48 h from the model induction, behavioral tasks and biochemical analyses were performed, respectively. AßOs impaired object recognition (OR) short-term memory and reduced glutamate uptake and oxidation in the hippocampus. Moreover, AßOs decreased spare respiratory capacity, reduced ATP levels, impaired Ca2+ handling, and caused mitochondrial swelling in hippocampal synaptosomes. Guanosine crossed the BBB, recovered OR short-term memory, reestablished glutamate uptake, recovered mitochondrial Ca2+ homeostasis, and partially prevented mitochondrial swelling. Therefore, this endogenous purine presented a neuroprotective effect on presynaptic mitochondria and should be considered for further studies in AD models.

Characterization and antiproliferative activity of glioma-derived extracellular vesicles.

Aim: To characterize a method to isolate glioma-derived extracellular vesicles (GEVs) and understand their role in immune system modulation and glioma progression. Materials & methods: GEVs were isolated by differential centrifugation from C6 cell supernatant and characterized by size and expression of CD9, HSP70, CD39 and CD73. The glioma model was performed by injecting C6 glioma cells into the right striatum of Wistar rats in the following groups: controls (C6 cells alone), coinjection (C6 cells + GEVs) and GEVs by intranasal administration followed by immune cells, tumor size and cells proliferation analyses. Results: GEVs presented uniform size (175 nm), expressed CD9, HSP70, CD39, CD73 and produced adenosine. In vivo, we observed a reduction in tumor size, in cell proliferation (Ki-67) and in a regulatory cell marker (FoxP3). Conclusion: GEVs, administered before or at tumor challenge, have antiproliferative properties and reduce regulatory cells in the glioma microenvironment.

The neuroprotective role of melatonin in a gestational hypermethioninemia model.

Elevated levels of methionine in blood characterize the hypermethioninemia, which may have genetic or non-genetic origin, as for example from high protein diet. Born rats from hypermethioninemic mothers presented cerebral oxidative stress, inhibition of Na+,K+-ATPase, memory deficit and ultrastructure cerebral changes. Melatonin is a hormone involved in circadian rhythm and has antioxidant effects. The aim of this study was to verify the possible neuroprotective effects of melatonin administration in hypermethioninemic pregnant rats on damage to biomolecules (Na+,K+-ATPase, sulfhydryl content and DNA damage index) and behavior (open field, novel object recognition and water maze tasks), as well as its effect on cells morphology by electron microscopy in offspring. Wistar female rats received methionine (2.68 µmol/g body weight) and/or melatonin (10 mg/kg body weight) by subcutaneous injections during entire pregnancy. Control rats received saline. Biochemical analyzes were performed at 21 and 30 days of life of offspring and behavioral analyzes were performed only at 30 days of age in male pups. Results showed that gestational hypermethioninemia diminished Na+,K+-ATPase activity and sulfhydryl content and increased DNA damage at 21 and 30 days of life. Melatonin was able to totally prevent Na+,K+-ATPase activity alteration at 21 days and partially prevent its alteration at 30 days of rats life. Melatonin was unable in to prevent sulfhydryl and DNA damage at two ages. It also improved DNA damage, but not at level of saline animals (controls). Regarding to behavioral tests, data showed that pups exposed to gestational hypermethioninemia decreased reference memory in water maze, spent more time to the center of the open field and did not differentiate the objects in the recognition test. Melatonin was able to prevent the deficit in novel object recognition task. Electron microscopy revealed ultrastructure alterations in neurons of hypermethioninemic at both ages of offspring, whose were prevented by melatonin. These findings suggest that melatonin may be a good neuroprotective to minimize the harmful effects of gestational hypermethioninemia on offspring.

Exogenous expression of caveolin-1 is sufficient for hepatic stellate cell activation.

Caveolin-1 (Cav-1) expression is increased in hepatic stellate cells (HSC) upon liver cirrhosis and it functions as an integral membrane protein of lipid rafts and caveolae that regulates and integrates multiple signals as a platform. This study aimed to evaluate the role of Cav-1 in HSC. Thus, the effects of exogenous expression of Cav-1 in GRX cells, a model of activated HSC, were determined. Here, we demonstrated through evaluating well-known HSC activation markers - such as α-smooth muscle actin, collagen I, and glial fibrillary acidic protein - that up regulation of Cav-1 induced GRX to a more activated phenotype. GRXEGFP-Cav1 presented an increased migration, an altered adhesion pattern, a reorganization f-actin cytoskeleton, an arrested cell cycle, a modified cellular ultrastructure, and a raised endocytic flux. Based on this, GRX EGFP-Cav1 represents a new cellular model that can be an important tool for understanding of events related to HSC activation. Furthermore, our results reinforce the role of Cav-1 as a molecular marker of HSC activation.

Dipyridamole impairs autophagic flux and exerts antiproliferative activity on prostate cancer cells.

Autophagy is a cellular bulk degradation process used as an alternative source of energy and metabolites and implicated in various diseases. Inefficient autophagy in nutrient-deprived cancer cells would be beneficial for cancer therapy making its modulation valuable as a therapeutic strategy for cancer treatment, especially in combination with chemotherapy. Dipyridamole (DIP) is a vasodilator and antithrombotic drug. Its major effects involve the block of nucleoside uptake and phosphodiestesase inhibition, leading to increased levels of intracellular cAMP. Here we report that DIP increases autophagic markers due to autophagic flux blockage, resembling autophagosome maturation and/or closure impairment. Treatment with DIP results in an increased number of autophagosomes and autolysosomes and impairs degradation of SQSTM1/p62. As blockage of autophagic flux decreases the recycling of cellular components, DIP reduced the intracellular ATP levels in cancer cells. Autophagic flux blockage was neither through inhibition of lysosome function nor blockage of nucleoside uptake, but could be prevented by treatment with a PKA inhibitor, suggesting that autophagic flux failure mediated by DIP results from increased intracellular levels of cAMP. Treatment with DIP presented antiproliferative effects in vitro alone and in combination with chemotherapy drugs. Collectively, these data demonstrate that DIP can impair autophagic degradation, by preventing the normal autophagosome maturation, and might be useful in combination anticancer therapy.

Neuroprotective Effects of Guanosine Administration on In Vivo Cortical Focal Ischemia in Female and Male Wistar Rats.

Guanosine (GUO) has neuroprotective effects in experimental models of brain diseases involving glutamatergic excitotoxicity in male animals; however, its effects in female animals are poorly understood. Thus, we investigated the influence of gender and GUO treatment in adult male and female Wistar rats submitted to focal permanent cerebral ischemia in the motor cortex brain. Female rats were subdivided into non-estrogenic and estrogenic phase groups by estrous cycle verification. Immediately after surgeries, the ischemic animals were treated with GUO or a saline solution. Open field and elevated plus maze tasks were conducted with ischemic and naïve animals. Cylinder task, immunohistochemistry and infarct volume analyses were conducted only with ischemic animals. Female GUO groups achieved a full recovery of the forelimb symmetry at 28-35 days after the insult, while male GUO groups only partially recovered at 42 days, in the final evaluation. The ischemic insult affected long-term memory habituation to novelty only in female groups. Anxiety-like behavior, astrocyte morphology and infarct volume were not affected. Regardless the estrous cycle, the ischemic injury affected differently female and male animals. Thus, this study points that GUO is a potential neuroprotective compound in experimental stroke and that more studies, considering the estrous cycle, with both genders are recommended in future investigation concerning brain diseases.

Methionine Administration in Pregnant Rats Causes Memory Deficit in the Offspring and Alters Ultrastructure in Brain Tissue.

In the present work, we evaluated the effect of gestational hypermethioninemia on locomotor activity, anxiety, memory, and exploratory behavior of rat offspring through the following behavior tests: open field, object recognition, and inhibitory avoidance. Histological analysis was also done in the brain tissue of pups. Wistar female rats received methionine (2.68 µmol/g body weight) by subcutaneous injections during pregnancy. Control rats received saline. Histological analyses were made in brain tissue from 21 and 30 days of age pups. Another group was left to recover until the 30th day of life to perform behavior tests. Results from open field task showed that pups exposed to methionine during intrauterine development spent more time in the center of the arena. In the object recognition memory task, we observed that methionine administration during pregnancy reduced total exploration time of rat offspring during training session. The test session showed that methionine reduced the recognition index. Regarding to inhibitory avoidance task, the decrease in the step-down latency at 1 and 24 h after training demonstrated that maternal hypermethioninemia impaired short-term and long-term memories of rat offspring. Electron microscopy revealed alterations in the ultrastructure of neurons at 21 and 30 days of age. Our findings suggest that the cell morphological changes caused by maternal hypermethioninemia may be, at least partially, associated to the memory deficit of rat offspring.

Chronic Mild Hyperhomocysteinemia Alters Inflammatory and Oxidative/Nitrative Status and Causes Protein/DNA Damage, as well as Ultrastructural Changes in Cerebral Cortex: Is Acetylsalicylic Acid Neuroprotective?

Homocysteine is a sulfur-containing amino acid derived from methionine metabolism. When plasma homocysteine levels exceed 10-15 µM, there is a condition known as hyperhomocysteinemia, which occur as a result of an inborn error of methionine metabolism or by non-genetic causes. Mild hyperhomocysteinemia is considered a risk factor for development of neurodegenerative diseases. The objective of the present study was to evaluate whether acetylsalicylic acid has neuroprotective role on the effect of homocysteine on inflammatory, oxidative/nitrative stress, and morphological parameters in cerebral cortex of rats subjected to chronic mild hyperhomocysteinemia. Wistar male rats received homocysteine (0.03 µmol/g of body weight) by subcutaneous injections twice a day and acetylsalicylic acid (25 mg/Kg of body weight) by intraperitoneal injections once a day from the 30th to the 60th postpartum day. Control rats received vehicle solution in the same volume. Results showed that rats subjected to chronic mild hyperhomocysteinemia significantly increased IL-1ß, IL-6, and acetylcholinesterase activity and reduced nitrite levels. Homocysteine decreased catalase activity and immunocontent and superoxide dismutase activity, caused protein and DNA damage, and altered neurons ultrastructure. Acetylsalicylic acid totally prevented the effect of homocysteine on acetylcholinesterase activity and catalase activity and immunocontent, as well as the ultrastructural changes, and partially prevented alterations on IL-1ß levels, superoxide dismutase activity, sulfhydryl content, and comet assay. Acetylsalicylic acid per se increased DNA damage index. In summary, our findings showed that chronic chemically induced model of mild hyperhomocysteinemia altered some parameters and acetylsalicylic acid administration seemed to be neuroprotective, at least in part, on neurotoxicity of homocysteine.

Effect of u18666a on beta-glucosidase, sphingomyelinase, and beta-galactosidase activities in astrocytes of young rats.

Niemann-Pick type C disease (NPC) is a neurodegenerative genetic disorder caused by accumulation of lipids, especially cholesterol, in the perinuclear space. U18666A is a cholesterol transport-inhibiting agent, being used to mimic NPC, mainly in fibroblasts. The objective of this study was to observe the effect of the drug U18666A, which causes the accumulation of cholesterol in the cytoplasm of astrocytes from newborn rats, on some lysosomal hydrolase activities. Filipin staining and fluorescence microscopy, through CellM software, were used for visualization and quantification of cholesterol. The dose of U18666A that provided the greatest accumulation of cholesterol was that of 0.25 µg/mL in incubation for 48 h. Primary rat astrocytes incubated with the drug (NPC) showed a significantly higher amount of cholesterol than those without U18666A (controls). The measurement of activity of enzymes sphingomyelinase and beta-glucosidase in astrocytes of rats with NPC was significantly lower than that of control astrocytes, which is consistent with the disease in humans. The activity of the enzyme beta-galactosidase showed no significant difference between both groups. We concluded that U18666A appears to be an excellent intracellular cholesterol transport-inhibiting agent affecting some metabolic pathways in astrocytes of young rats, which mimics NPC in these animals. Just like the change in the activity of lysosomal enzymes has been demonstrated, other biochemical parameters of the cell can be tested with this animal model, thus contributing to a better understanding of the disease.

Obesity associated with type 2 diabetes mellitus is linked to decreased PC1/3 mRNA expression in the Jejunum.

BACKGROUND: Bariatric surgery is the most effective therapeutic option for obesity and its complications, especially in type 2 diabetes. The aim of this study was to investigate the messenger RNA (mRNA) gene expression of proglucagon, glucose-dependent insulinotropic peptide (GIP), prohormone convertase 1/3 (PC1/3), and dipeptidyl peptidase-IV (DPP-IV) in jejunum cells of the morbidly obese (OB) non type 2 diabetes mellitus (NDM2) and type 2 diabetes mellitus (T2DM), to determine the molecular basis of incretin secretion after bariatric surgery. METHODS: Samples of jejunal mucosa were obtained from 20 NDM2 patients: removal of a section of the jejunum about 60 cm distal to the ligament of Treitz and 18 T2DM patients: removal of a section of the jejunum about 100 cm distal to the ligament of Treitz. Total RNA was extracted using TRIzol. Reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) was carried out. Samples were sequenced to PC1/3 by ACTGene Análises Moleculares Ltd. Immuno content was quantified with a fluorescence microscope. RESULTS: T2DM showed decreased PC1/3 mRNA expression in the primers tested (primer a, p=0.014; primer b, p=0.048). Many patients (36.5 %) did not express PC1/3 mRNA. NDM2 and T2DM subjects showed nonsignificantly different proglucagon, GIP, and DPP-IV mRNA expression. The immuno contents of glucagon-like peptide-1 and GIP decreased in T2DM jejunum, but incubation with high glucose stimulated the immuno contents. CONCLUSIONS: The results suggest that bioactivation of pro-GIP and proglucagon could be impaired by the lower expression of PC1/3 mRNA in jejunum cells of obese patients with T2DM. However, after surgery, food could activate this system and improve glucose levels in these patients.

Parallel down-regulation of FOXO1, PPARγ and adiponectin mRNA expression in visceral adipose tissue of class III obese individuals.

OBJECTIVE: Adipose tissue is responsible for secretion of several cytokines that mediate systemic effects on obesity and insulin resistance. Subcutaneous abdominal adipose tissue (SAT) and visceral adipose tissue (VAT) are metabolically different and have differences in their gene expression profile. Our study evaluated the expression of adiponectin, FOXO1, PPARγ, and SIRT1 in VAT and SAT of non-obese and class III obese subjects. METHODS: The adipose tissue samples were obtained by surgery. Reverse transcripts of studied genes were determined by quantitative real-time polymerase chain reaction (qRT-PCR). RESULTS: Comparing the different lipid depots, adiponectin expression was lower only in VAT of obese individuals (p = 0.043); FOXO1 and PPARγ levels were decreased in VAT of both groups. When non-obese and obese were compared, only adiponectin expression was lower in SAT and in VAT of obese subjects (p = 0.004 and p = 0.002, respectively). No difference was found with regard to SIRT1 levels in VAT or SAT in both groups. FOXO1 expression in SAT of obese subjects had a negative correlation with age (r = -0.683; p = 0.029) and triglyceride serum levels (r = -0.794; p = 0.006). CONCLUSION: The decrease mRNA expression of this genes in VAT, responsible for central adiposity, may be associated with an increased risk of obesity and co-morbidities.

Resveratrol upregulated SIRT1, FOXO1, and adiponectin and downregulated PPARγ1-3 mRNA expression in human visceral adipocytes.

BACKGROUND: The SIRT1 enzyme is involved in adipose tissue (AT) lipolysis. FOXO1 is a protein that plays a significant role in regulating metabolism. Adiponectin is an adipokine, secreted by the AT, which has been considered to have an antiobesity function. PPARγ is one of the key actors in adipocytes differentiation. This study was undertaken to investigate whether resveratrol can regulate SIRT1, FOXO1, adiponectin, PPARγ1-3, and PPARß/δ in human AT. METHODS: The effects of resveratrol were analyzed in freshly isolated adipocytes prepared from visceral fat tissue samples obtained during bariatric surgery. Genes messenger ribonucleic acid (mRNA) levels were determined by qRT-PCR. RESULTS: Ours results show that resveratrol modulates the studied genes, increasing SIRT1 (p = 0.021), FOXO1 (p = 0.001), and adiponectin (p = 0.025) mRNA expression and decreasing PPARγ1-3 (p = 0.003) mRNA in human visceral adipocytes. CONCLUSIONS: Resveratrol, in vitro and at low concentration, modulates genes that are related to lipid metabolism, possibly preventing metabolic disease in human visceral adipose tissue (VAT).

SIRT1 transcription is decreased in visceral adipose tissue of morbidly obese patients with severe hepatic steatosis.

BACKGROUND: Visceral adipose tissue is known to release greater amounts of adipokines and free fatty acids into the portal vein, being one of the most predictive factors of nonalcoholic fatty liver disease (NAFLD). Our study has the purpose to evaluate sirtuin 1 (SIRT1), adiponectin, Forkhead/winged helix (FOXO1), peroxisome proliferator-activated receptor (PPAR)gamma1-3, and PPARbeta/delta mRNA expression in morbidly obese patients in three different lipid depots: visceral (VAT), subcutaneous (SAT), and retroperitoneal (RAT). Recent studies suggest that SIRT1, a NAD(+)-dependent deacetylase, protects rats from NAFLD. METHODS: We divided the patients in two groups: those with slight or moderate steatosis (hepatic steatosis, HS) and other comprising individuals with severe steatosis associated or not with necroinflammation and fibrosis (severe hepatic steatosis, SHS). The adipose tissue depots were obtained during bariatric surgery. Total RNAs were extracted using TRIzol. The amount of genes of interest was determined by quantitative real-time polymerase chain reaction. RESULTS: When comparing the two groups of patients, a decrease in SIRT1 was observed in VAT of morbidly obese patients in SHS group (p = 0.006). The mRNA expression of the other genes showed no differences in VAT. No difference was found either in SAT or in RAT for all genes in the study. In addition, the homeostasis model assessment for insulin resistance (HOMA-IR) value was higher in SHS group compared to HS (p = 0.006). Also, our results show that the mRNA expression of SIRT1 and the value of HOMA-IR were positively correlated in VAT of SHS patients (r = 0.654; p = 0.048). CONCLUSIONS: Downregulation of SIRT1 mRNA expression in VAT of SHS could be possible impairing mitochondria biogenesis and fatty acid oxidation, promoting severe steatosis in obese patients. Our results provide a possible proof of SIRT1 protective potential in VAT against NAFLD in humans.

Monitoramento microbiológico de águas subterrâneas em cidades do Extremo Oeste de Santa Catarina / Microbiological monitoring of underground waters in cities of the Extreme West of Santa Catarina State

A degradação dos recursos naturais vem aumentando em números alarmantes, principalmente, as fontes hídricas. Devido a isto, cada vez mais as populações vêm utilizando águas subterrâneas para consumo humano. Contudo, o grande problema é a contaminação destas por microrganismos patogênicos. O objetivo do presente estudo foi avaliar a qualidade microbiológica de águas subterrâneas em municípios do Extremo Oeste de Santa Catarina. Foram analisadas 149 amostras de água de poços em catorze municípios, durante o período de janeiro de 2005 a dezembro de 2006. Foram determinados em todas as amostras os números mais prováveis de coliformes totais e termotolerantes. Os resultados apresentaram altos índices de amostras impróprias para consumo, com 54,7 por cento em 2005 e 56,7 por cento em 2006. Os nossos dados evidenciam os riscos para doenças de veiculação hídrica que a população da região está exposta com o consumo desta água, mostrando um grave problema de saúde pública.

The degradation of natural resources is increasing in alarming numbers, especially water sources that is constant changes in its quality. Because of this, more and more people come using groundwater for human consumption, but the big problem is contamination by these pathogenic microorganisms. The purpose of this study was to evaluate the microbiological quality of groundwater districts in the Extreme West of Santa Catarina, Brazil. We analyzed 149 samples of water from wells in 14 municipalities during the period January 2005 to December 2006. Were determined in all samples the total coliform and thermotolerant. The results showed high rates of samples inappropriate for consumption, with 54.7 percent in 2005 and 56.7 percent in 2006. Our data show the risk of diseases spreading of water that the region's population is exposed to the consumption of water, showing a serious public health problem.

[Microbiological monitoring of underground waters in cities of the Extreme West of Santa Catarina State]. / Monitoramento microbiológico de águas subterrâneas em cidades do Extremo Oeste de Santa Catarina.

The degradation of natural resources is increasing in alarming numbers, especially water sources that is constant changes in its quality. Because of this, more and more people come using groundwater for human consumption, but the big problem is contamination by these pathogenic microorganisms. The purpose of this study was to evaluate the microbiological quality of groundwater districts in the Extreme West of Santa Catarina, Brazil. We analyzed 149 samples of water from wells in 14 municipalities during the period January 2005 to December 2006. Were determined in all samples the total coliform and thermotolerant. The results showed high rates of samples inappropriate for consumption, with 54.7% in 2005 and 56.7% in 2006. Our data show the risk of diseases spreading of water that the region's population is exposed to the consumption of water, showing a serious public health problem.