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1.
Braz J Med Biol Res ; 49(8)2016 Jul 28.
Article in English | MEDLINE | ID: mdl-27487419

ABSTRACT

Due to the presence of the renin-angiotensin system (RAS) in tissues and its specific influence on white adipose tissue, fat cells are possible targets of pharmacological RAS blockers commonly used as anti-hypertensive drugs. In the present study, we investigated the effects of different RAS blockers on fat cell metabolism, more specifically on lipolysis, lipogenesis and oxidation of energy substrates. Isolated primary adipocytes were incubated with different RAS blockers (aliskiren, captopril and losartan) in vitro for 24 h and lipolysis, lipogenesis and glucose oxidation capacities were determined in dose-response assays to a ß-adrenergic agonist and to insulin. Although no change was found in lipolytic capacity, the RAS blockers modulated lipogenesis and glucose oxidation in a different way. While captopril decreased insulin-stimulated lipogenesis (-19% of maximal response and -60% of insulin responsiveness) due to reduced glucose derived glycerol synthesis (-19% of maximal response and 64% of insulin responsiveness), aliskiren increased insulin-stimulated glucose oxidation (+49% of maximal response and +292% of insulin responsiveness) in fat cells. Our experiments demonstrate that RAS blockers can differentially induce metabolic alterations in adipocyte metabolism, characterized by a reduction in lipogenic responsiveness or an increase in glucose oxidation. The impact of RAS blockers on adipocyte metabolism may have beneficial implications on metabolic disorders during their therapeutic use in hypertensive patients.


Subject(s)
Adipocytes/drug effects , Antihypertensive Agents/pharmacology , Renin-Angiotensin System/drug effects , Adipocytes/metabolism , Amides/pharmacology , Animals , Captopril/pharmacology , Fumarates/pharmacology , Glucose/metabolism , Glycerol/metabolism , Lipogenesis/drug effects , Lipolysis/drug effects , Losartan/pharmacology , Male , Rats, Wistar
2.
Braz. j. med. biol. res ; 49(8): e5409, 2016. graf
Article in English | LILACS | ID: lil-787387

ABSTRACT

Due to the presence of the renin-angiotensin system (RAS) in tissues and its specific influence on white adipose tissue, fat cells are possible targets of pharmacological RAS blockers commonly used as anti-hypertensive drugs. In the present study, we investigated the effects of different RAS blockers on fat cell metabolism, more specifically on lipolysis, lipogenesis and oxidation of energy substrates. Isolated primary adipocytes were incubated with different RAS blockers (aliskiren, captopril and losartan) in vitro for 24 h and lipolysis, lipogenesis and glucose oxidation capacities were determined in dose-response assays to a β-adrenergic agonist and to insulin. Although no change was found in lipolytic capacity, the RAS blockers modulated lipogenesis and glucose oxidation in a different way. While captopril decreased insulin-stimulated lipogenesis (−19% of maximal response and −60% of insulin responsiveness) due to reduced glucose derived glycerol synthesis (−19% of maximal response and 64% of insulin responsiveness), aliskiren increased insulin-stimulated glucose oxidation (+49% of maximal response and +292% of insulin responsiveness) in fat cells. Our experiments demonstrate that RAS blockers can differentially induce metabolic alterations in adipocyte metabolism, characterized by a reduction in lipogenic responsiveness or an increase in glucose oxidation. The impact of RAS blockers on adipocyte metabolism may have beneficial implications on metabolic disorders during their therapeutic use in hypertensive patients.


Subject(s)
Animals , Male , Renin-Angiotensin System/drug effects , Adipocytes/drug effects , Antihypertensive Agents/pharmacology , Captopril/pharmacology , Rats, Wistar , Adipocytes/metabolism , Losartan/pharmacology , Lipogenesis/drug effects , Fumarates/pharmacology , Amides/pharmacology , Glucose/metabolism , Glycerol/metabolism , Lipolysis/drug effects
3.
Braz. j. med. biol. res ; 48(7): 650-653, 07/2015. graf
Article in English | LILACS | ID: lil-751343

ABSTRACT

As it is a common observation that obesity tends to occur after discontinuation of exercise, we investigated how white adipocytes isolated from the periepididymal fat of animals with interrupted physical training transport and oxidize glucose, and whether these adaptations support the weight regain seen after 4 weeks of physical detraining. Male Wistar rats (45 days old, weighing 200 g) were divided into two groups (n=10): group D (detrained), trained for 8 weeks and detrained for 4 weeks; and group S (sedentary). The physical exercise was carried out on a treadmill for 60 min/day, 5 days/week for 8 weeks, at 50-60% of the maximum running capacity. After the training protocol, adipocytes isolated from the periepididymal adipose tissue were submitted to glucose uptake and oxidation tests. Adipocytes from detrained animals increased their glucose uptake capacity by 18.5% compared with those from sedentary animals (P<0.05). The same cells also showed a greater glucose oxidation capacity in response to insulin stimulation (34.55%) compared with those from the S group (P<0.05). We hypothesize that, owing to the more intense glucose entrance into adipose cells from detrained rats, more substrate became available for triacylglycerol synthesis. Furthermore, this increased glucose oxidation rate allowed an increase in energy supply for triacylglycerol synthesis. Thus, physical detraining might play a role as a possible obesogenic factor for increasing glucose uptake and oxidation by adipocytes.


Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Agricultural Workers' Diseases/chemically induced , Occupational Exposure/adverse effects , Parkinson Disease, Secondary/chemically induced , Pesticides/toxicity , California , Case-Control Studies , Models, Statistical , Occupational Exposure/statistics & numerical data , Propensity Score , Risk Factors
4.
Braz J Med Biol Res ; 48(7): 650-3, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26017340

ABSTRACT

As it is a common observation that obesity tends to occur after discontinuation of exercise, we investigated how white adipocytes isolated from the periepididymal fat of animals with interrupted physical training transport and oxidize glucose, and whether these adaptations support the weight regain seen after 4 weeks of physical detraining. Male Wistar rats (45 days old, weighing 200 g) were divided into two groups (n=10): group D (detrained), trained for 8 weeks and detrained for 4 weeks; and group S (sedentary). The physical exercise was carried out on a treadmill for 60 min/day, 5 days/week for 8 weeks, at 50-60% of the maximum running capacity. After the training protocol, adipocytes isolated from the periepididymal adipose tissue were submitted to glucose uptake and oxidation tests. Adipocytes from detrained animals increased their glucose uptake capacity by 18.5% compared with those from sedentary animals (P<0.05). The same cells also showed a greater glucose oxidation capacity in response to insulin stimulation (34.55%) compared with those from the S group (P<0.05). We hypothesize that, owing to the more intense glucose entrance into adipose cells from detrained rats, more substrate became available for triacylglycerol synthesis. Furthermore, this increased glucose oxidation rate allowed an increase in energy supply for triacylglycerol synthesis. Thus, physical detraining might play a role as a possible obesogenic factor for increasing glucose uptake and oxidation by adipocytes.


Subject(s)
Adipose Tissue, White/metabolism , Glucose Transport Proteins, Facilitative/metabolism , Glucose/metabolism , Physical Conditioning, Animal/physiology , Weight Gain/physiology , Adipocytes/metabolism , Animals , Carbon Dioxide/metabolism , Insulin/metabolism , Male , Oxidation-Reduction , Rats, Wistar , Time Factors
5.
J Fish Biol ; 86(6): 1713-28, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25903107

ABSTRACT

This study employed a non-lethal measurement tool, which combined an existing photo-identification technique with a surface, parallel laser photogrammetry technique, to accurately estimate the size of free-ranging white sharks Carcharodon carcharias. Findings confirmed the hypothesis that surface laser photogrammetry is more accurate than crew-based estimations that utilized a shark cage of known size as a reference tool. Furthermore, field implementation also revealed that the photographer's angle of reference and the shark's body curvature could greatly influence technique accuracy, exposing two limitations. The findings showed minor inconsistencies with previous studies that examined pre-caudal to total length ratios of dead specimens. This study suggests that surface laser photogrammetry can successfully increase length estimation accuracy and illustrates the potential utility of this technique for growth and stock assessments on free-ranging marine organisms, which will lead to an improvement of the adaptive management of the species.


Subject(s)
Photogrammetry/methods , Sharks/anatomy & histology , Animals , Body Size , Lasers
6.
Acta Physiol (Oxf) ; 211(2): 409-20, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24410866

ABSTRACT

AIM: Glucocorticoid (GC) in excess promotes the redistribution of adipose tissue from peripheral to central sites of the body. In this study, we characterized an experimental condition of prolonged GC excess and investigated its effect on the lipogenic metabolism in white adipose tissue. METHODS: Twenty male Wistar rats were divided into control (CON) and dexamethasone-treated (DEX) groups. DEX group received dexamethasone (0.25 mg kg(-1) day(-1) ) during 4 weeks, while CON group received saline. Animals were killed and subcutaneous (SC), retroperitoneal (RP) and mesenteric (MS) fat pads were excised, weighed and processed for adipocyte isolation, morphometric cell analysis and incorporation of glucose into lipids. RESULTS: The treatment effectively blocked hypothalamic-pituitary-adrenal axis, as verified by a 58% decrease in plasma corticosterone levels and 19% atrophy in adrenal glands in DEX group. Animals from DEX group presented insulin resistance, glucose intolerance, dyslipidaemia and increased insulin and leptin plasma levels and hypertrophied adipocytes. They showed increased lipogenesis in RP and MS depots, with increased incorporation of glucose into fatty acids of triacylglycerol. Increased activity of lipogenic enzymes ATP-citrate lyase, fatty acid synthase, glucose-6-phosphate dehydrogenase and malic was only seen in the MS depot in DEX group, while gene expression of these enzymes was enhanced in SC and MS fat depots. CONCLUSION: The adaptations promoted by GC treatment in adipose metabolism seemed to be mainly due to the increased activity of enzymes that supply the NADPH required for lipogenesis than to the increase in enzymes that more directly deal with fatty acid synthesis itself.


Subject(s)
Adipocytes, White/drug effects , Dexamethasone/adverse effects , Glucocorticoids/adverse effects , Intra-Abdominal Fat/drug effects , Lipogenesis/drug effects , Animals , Hypothalamo-Hypophyseal System/drug effects , Male , Pituitary-Adrenal System/drug effects , Rats , Rats, Wistar , Real-Time Polymerase Chain Reaction
7.
Lett Appl Microbiol ; 47(4): 309-14, 2008 Oct.
Article in English | MEDLINE | ID: mdl-19241525

ABSTRACT

AIMS: This study compared the in vitro activity of telithromycin with that of azithromycin against 438 Streptococcus pyogenes and 198 Streptococcus pneumoniae, isolated over the period 2005-2007 from specimens of different human origin obtained in three Piemonte Region's hospitals. METHODS AND RESULTS: The determination of antimicrobial activity was evaluated by the microdilution broth method and the erythromycin-resistant (Ery-R) phenotypes by the triple-disc test. Exactly 78.8% of S. pyogenes and 69.2% of S. pneumoniae were erythromycin-susceptible (Ery-S). Concerning S. pyogenes, telithromycin was active against M and inducible MLS(B), subtype-C, phenotypes but not against constitutive MLS(B) strains. Telithromycin acted well against all S. pneumoniae, irrespective of their mechanism of macrolide-resistance. On the contrary, the Ery-R isolates, both S. pyogenes and S. pneumoniae, were resistant to azithromycin. CONCLUSIONS: Our results indicate that macrolide resistance in streptococci still persist in northwest Italy (21.2% of S. pyogenes and 308% of S. pneumoniae) and that telithromycin is confirmed as being extremely active even against recent clinical Ery-R streptococcal isolates. SIGNIFICANCE AND IMPACT OF THE STUDY: The present study emphasizes that an active surveillance of the phenotype distribution and antibacterial resistance in streptococci is essential in guiding the effective use of empirical treatment option for streptococcal infections, also at regional level.


Subject(s)
Anti-Bacterial Agents/pharmacology , Azithromycin/pharmacology , Ketolides/pharmacology , Streptococcus pneumoniae/drug effects , Streptococcus pyogenes/drug effects , Adult , Child , Drug Resistance, Bacterial , Erythromycin/pharmacology , Humans , Italy , Microbial Sensitivity Tests , Streptococcal Infections/microbiology , Streptococcus pneumoniae/isolation & purification
8.
Horm Metab Res ; 36(7): 474-9, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15305231

ABSTRACT

We investigated the effects of pinealectomy on adipose tissue metabolism at different times of day. Adult male Wistar rats were divided into two groups: pinealectomized and control (sham-operated). Eight weeks after surgery, the animals were killed at three different times (at 8.00 a.m., at 4.00 p.m. and 11.00 p.m.). We collected blood samples for glucose, insulin, corticosterone, and leptin determinations, and periepididymal adipocytes for in vitro insulin-stimulated glucose uptake, oxidation, and incorporation into lipids. Pinealectomy caused insulin resistance as measured by 2-deoxyglucose uptake (a fall of approximately 40 % in the maximally insulin-stimulated rates) accompanied by hypercorticosteronemia at the three time points investigated without changes in plasma insulin an or leptin levels. Furthermore, pinealectomy increased the insulin-induced glucose incorporation into lipids (77 %) at 4.00 p.m. and insulin-induced glucose oxidation in the morning and in the afternoon, while higher rates were observed in the evening and in the morning in control rats. In conclusion, cell responsiveness to insulin was differentially affected by pineal ablation and time of day, and persistent insulin resistance was obtained in pinealectomized rats. We hypothesize that pinealectomy exposes the animal to an inadequate match between energy requirements and fuel mobilization.


Subject(s)
Adipocytes/metabolism , Circadian Rhythm/physiology , Corticosterone/blood , Insulin Resistance/physiology , Pineal Gland/physiology , Adipocytes/radiation effects , Adipose Tissue/metabolism , Adipose Tissue/radiation effects , Analysis of Variance , Animals , Blood Glucose/metabolism , Body Weight/physiology , Body Weight/radiation effects , Energy Metabolism/physiology , Energy Metabolism/radiation effects , Insulin/blood , Insulin Resistance/radiation effects , Leptin/blood , Light , Lipid Metabolism , Male , Melatonin/physiology , Photoperiod , Rats , Rats, Wistar , Receptor, Insulin/metabolism , Receptor, Insulin/radiation effects
9.
Eur J Histochem ; 45(1): 39-49, 2001.
Article in English | MEDLINE | ID: mdl-11411863

ABSTRACT

Arbuscular mycorrhizal (AM) fungi, one of the most important component of the soil microbial community, establish physical interactions with naturally occurring and genetically modified bacterial biofertilizers and biopesticides, commonly referred to as plant growth-promoting rhizobacteria (PGPR). We have used a genetic approach to investigate the bacterial components possibly involved in the attachment of two PGPR (Azospirillum and Rhizobium) to AM roots and AM fungal structures. Mutants affected in extracellular polysaccharides (EPS) have been tested in in vitro adhesion assays and shown to be strongly impaired in the attachment to both types of surfaces as well as to quartz fibers. Anchoring of rhizobacteria to AM fungal structures may have special ecological and biotechnological significance because it may facilitate colonisation of new rhizospheres by the bacteria, and may be an essential trait for the development of mixed inocula.


Subject(s)
Attachment Sites, Microbiological/genetics , Azospirillum brasilense/genetics , Bacterial Adhesion/genetics , Fungi/physiology , Polysaccharides, Bacterial/genetics , Rhizobium leguminosarum/genetics , Azospirillum brasilense/classification , In Vitro Techniques , Microscopy, Confocal , Rhizobium leguminosarum/classification
10.
Mol Plant Microbe Interact ; 14(2): 255-60, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11204790

ABSTRACT

Extracellular polysaccharides play an important role in the formation of bacterial biofilms. We tested the biofilm-forming ability of two mutant strains with increased production of acidic extracellular polysaccharides compared with the wild-type biocontrol strain Pseudomonas fluorescens CHA0. The anchoring of bacteria to axenic nonmycorrhizal and mycorrhizal roots as well as on extraradical mycelium of the arbuscular mycorrhizal fungus Glomus intraradices was investigated. The nonmucoid wild-type strain P. fluorescens CHA0 adhered very little on all surfaces, whereas both mucoid strains formed a dense and patchy bacterial layer on the roots and fungal structures. Increased adhesive properties of plant-growth-promoting bacteria may lead to more stable interactions in mixed inocula and the rhizosphere.


Subject(s)
Fungi/isolation & purification , Mutation , Pest Control, Biological , Pseudomonas fluorescens/physiology , Vegetables/microbiology , Biofilms , Microscopy, Electron , Plant Roots/microbiology , Pseudomonas fluorescens/genetics , Pseudomonas fluorescens/ultrastructure
11.
Cochabamba; s.n; 1999. 95 p. ilus.
Monography in Spanish | LIBOCS, LILACS, LIBOSP | ID: biblio-1314399

ABSTRACT

Hallazgo polemico. Carta abierta a los operadores de salud. Acosado por la autoridad civil y religiosa. Santiago. Cambio de ruta. Expansion de la noticia. Manila. Roma. Trento. Epilogo


Subject(s)
Bolivia , Philippines , Tetanus Toxoid
12.
Minerva Ginecol ; 41(8): 401-4, 1989 Aug.
Article in Italian | MEDLINE | ID: mdl-2812491

ABSTRACT

Authors have examined 14 pregnant patients with renal involvement by systemic lupus erythematosus. Variations in blood creatinine, proteinuria and blood pressure were considered in the prepregnancy, pregnancy and postpartum periods in relation to the histologic results of renal biopsy and obstetric outcome.


Subject(s)
Lupus Nephritis/complications , Pregnancy Complications/pathology , Adult , Blood Pressure , Creatinine/blood , Female , Humans , Lupus Nephritis/blood , Lupus Nephritis/pathology , Lupus Nephritis/physiopathology , Lupus Nephritis/urine , Postpartum Period , Pregnancy , Pregnancy Complications/blood , Pregnancy Complications/physiopathology , Pregnancy Complications/urine , Proteinuria
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