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1.
Arch Pediatr ; 29(7): 530-533, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36058813

ABSTRACT

Bartter syndrome (BS) refers to a group of hereditary kidney disorders. One antenatal form is Bartter syndrome type 1 (BS1), caused by pathogenic variants in the SLC12A1 gene. We report a case of BS1 presenting with severe polyhydramnios. The fetus was found to carry three pathogenic variants of SLC12A1, leading to the antenatal diagnosis of BS1 and its prompt management. At age 18 days, clinical conditions were complicated by the onset of sepsis requiring supportive measures as well as steroid and antibiotic therapy. Any newborn with an antenatal history of polyhydramnios or postnatal polyuria should be suspected of having BS, since delayed diagnosis may lead to rapid renal failure.


Subject(s)
Bartter Syndrome , Polyhydramnios , Adolescent , Anti-Bacterial Agents , Bartter Syndrome/complications , Bartter Syndrome/diagnosis , Bartter Syndrome/genetics , Female , Humans , Infant, Newborn , Polyhydramnios/diagnosis , Polyhydramnios/etiology , Pregnancy , Solute Carrier Family 12, Member 1/genetics
2.
Hered Cancer Clin Pract ; 19(1): 45, 2021 Oct 27.
Article in English | MEDLINE | ID: mdl-34706754

ABSTRACT

BACKGROUND AND AIM: The BRCA 1 and BRCA 2 genes are associated with an inherited susceptibility to breast cancer with a cumulative risk of 60% in BRCA 1 mutation carriers and of 30% in BRCA 2 mutation carriers. Several lifestyle factors could play a role in determining an individual's risk of breast cancer. Obesity, changes in body size or unhealthy lifestyle habits such as smoking, alcohol consumption and physical inactivity have been evaluated as possible determinants of breast cancer risk. The aim of this study was to explore the current understanding of the role of harmful lifestyle and obesity or weight change in the development of breast cancer in female carriers of BRCA 1/2 mutations. METHODS: Articles were identified from MEDLINE in October 2020 utilizing related keywords; they were then read and notes, study participants, measures, data analysis and results were used to write this review. RESULTS: Studies with very large case series have been carried out but only few of them have shown consistent results. Additional research would be beneficial to better determine the actual role and impact of such factors.

3.
J Pers Med ; 11(3)2021 Mar 17.
Article in English | MEDLINE | ID: mdl-33802940

ABSTRACT

Unhealthy lifestyle, as sedentary, unbalanced diet, smoking, and body composition change are often observed in non-Hodgkin's lymphoma (NHL) survivors, and could be determinant for the onset of cancer treatment-induced metabolic syndrome (CTIMetS), including abdominal obesity, sarcopenia, and insulin resistance. The aim of this study was to assess whether changes in body composition, unhealthy lifestyles and types of anti-cancer treatment could increase the risk of metabolic syndrome (MetSyn) and sarcopenia in long-term NHL survivors. We enrolled 60 consecutive NHL patients in continuous remission for at least 3 years. Nutritional status was assessed by anthropometry-plicometry, and a questionnaire concerning lifestyles and eating habits was administered. More than 60% of survivors exhibited weight gain and a change in body composition, with an increased risk of MetSyn. Univariate analysis showed a significantly higher risk of metabolic disorder in patients treated with steroids, and in patients with unhealthy lifestyles. These data suggest that a nutritional intervention, associated with adequate physical activity and a healthier lifestyle, should be indicated early during the follow-up of lymphoma patients, in order to decrease the risk of MetSyn's onset and correlated diseases in the long term.

4.
Bull Environ Contam Toxicol ; 98(4): 508-512, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28204838

ABSTRACT

The lignicolous macrofungus Perenniporia fraxinea has drawn increased attention due to its role as a pathogen of ornamentals in urban sites. The present study investigated the bioaccumulation of heavy metals by P. fraxinea. Sporophores were collected from urban and suburban areas in Pavia (Northern Italy) and analyzed for metals content (Cd, Hg, Pb, Ni, Cr, Cu, Fe, Mn, Zn) by inductively coupled plasma mass spectrometer and inductively coupled plasma optical emission spectroscopy, after microwave acidic digestion. On the basis of the obtained results the potential bioaccumulation capability of P. fraxinea was investigated. The isolates were grown in a culture medium enriched with different concentrations of Cd and Hg, chosen as probes of environmental pollution, and Cu for comparison. As P. fraxinea grows in the presence of Cd, Hg and Cu, it seems to be a potential tool in environmental monitoring.


Subject(s)
Basidiomycota/chemistry , Metals, Heavy/analysis , Basidiomycota/growth & development , Cadmium/toxicity , Copper/toxicity , Environmental Monitoring/methods , Italy , Mercury/toxicity
5.
Int J Biochem Cell Biol ; 77(Pt A): 91-101, 2016 08.
Article in English | MEDLINE | ID: mdl-27267661

ABSTRACT

Matrix metalloproteinases are a family of zinc endopeptidases with proteolytic activity against the extracellular matrix components. In particular, two members of this family named Gelatinase A and B, as amply documented in the literature, play a key role in the process of tumor growth/metastasis in breast and hepatocellular carcinoma. Their activity is regulated by Tissue Inhibitor of metalloproteinases-1 and -2, which are the physiological inhibitor of Gelatinases A and B respectively. The aim of this review is to determine the current understanding of the clinical and prognostic role of Metalloproteinases-2 and -9 and their inhibitors in the course of breast cancer and liver diseases. Forty-one articles were selected from PubMed by entering the following keywords: liver diseases, breast cancer, MMP-2, TIMP-2; all articles were read and notes were made regarding the number of enrolled patients, pathology, measures, results and these data were used to write this review. Over-expression of both gelatinases is associated with the relapse of disease, metastasis, shorter overall survival in breast cancer and hepatocellular carcinoma and invasion and progression to tumors in chronic liver diseases, and MMPs/TIMPs ratio could be useful in the follow-up of these patients.


Subject(s)
Breast Neoplasms/diagnosis , Breast Neoplasms/metabolism , Liver Neoplasms/diagnosis , Liver Neoplasms/metabolism , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/metabolism , Tissue Inhibitor of Metalloproteinases/metabolism , Animals , Breast Neoplasms/pathology , Humans , Liver Neoplasms/pathology , Prognosis
6.
J Prev Alzheimers Dis ; 2(3): 178-183, 2015.
Article in English | MEDLINE | ID: mdl-29226944

ABSTRACT

OBJECTIVE: Delirium is a frequent clinical complication in geriatric patients admitted to the hospital, because of the simultaneous presence and synergistic effect of predisposing and precipitating factors. Also anaemia is a common concern in geriatric population. The aim of this study was to investigate the association between anaemia (precipitating factor) and delirium in a sample of Italian older hospitalized patients with different degree of cognitive impairment (predisposing factor). DESIGN, SETTING, PARTICIPANTS: Cross-sectional analysis of 1069 participants enrolled in the CRIME study, with assessment of hemoglobin levels at hospital admission. MEASUREMENTS: Delirium was assessed using DSM-IV criteria, whereas cognitive status was categorized as dementia, cognitive impairment or normal, according to clinical history, specific treatment and MMSE score. Anaemia was defined according to sex-specific WHO criteria. The association of hemoglobin levels and delirium was investigated with multivariable logistic regression models. RESULTS: Mean age of study participants was 81.4±7.2 years, 52.2% had prevalent anaemia, 6.1% had delirium. According to cognitive status 20.8% had dementia and 40.9% had cognitive impairment. Overall there was no association between anaemia and delirium. However, among patients with cognitive impairment (MMSE <24, no dementia) anaemia was significantly associated with the likelihood of delirium (p<0.006). Multivariate logistic regression analysis, adjusted for potential confounders, showed in these patients a graded increased risk of delirium according to anaemia severity with an almost six-fold increased risk of delirium in moderate-severe anaemia (OR 5.95, 95% CI:1.15-30.73). CONCLUSION: In older patients with cognitive impairment moderate-severe anaemia is independently associated with the likelihood of delirium. Further studies should investigate if anaemia correction would translate in delirium risk reduction.

7.
J Physiol Biochem ; 70(3): 791-800, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25034332

ABSTRACT

The aim of the present study was to assess whether the protective effects of ischemic preconditioning (PC) are associated with activation of the mitochondrial ATP-sensitive potassium channels (mitoKATP) and if there is any relationship between the activity of these channels and the mitochondrial permeability transition pore (MPTP) opening in ischemic-reperfused rat hearts under different nutritional conditions. Langendorff-perfused hearts of fed and 24-h fasted rats were exposed to 25 min of no-flow global ischemia plus 30 min of reperfusion. Fasting accelerated functional recovery and attenuated MPTP opening. The mitoKATP blocker, 5-hydroxydecanoic (HD), did not influence functional recovery and MPTP opening induced by ischemia-reperfusion in the fed hearts but partially reversed the beneficial effects of fasting. PC and the mitoKATP opener, diazoxide (DZ), improved functional recovery, preserved cell viability, and inhibited MPTP opening in both fed and fasted hearts. The protection elicited by PC and DZ on contractile recovery and MPTP opening was reversed by HD, which did not affect cell viability. Altogether, these results argue for a role of mitoKATP and its impact on preservation mitochondrial inner membrane permeability as a relevant factor in the improvement of contractile function in the ischemic-reperfused rat heart. They also suggest that the functional protection elicited by PC may be related to this mechanism.


Subject(s)
Ischemic Preconditioning, Myocardial/methods , Mitochondrial Membrane Transport Proteins/metabolism , Myocardial Reperfusion Injury/metabolism , Myocardial Reperfusion Injury/prevention & control , Potassium Channels/metabolism , Animals , Cardiotonic Agents/pharmacology , Decanoic Acids/pharmacology , Deoxyglucose/metabolism , Diazoxide/pharmacology , Fasting/metabolism , Female , Hydroxy Acids/pharmacology , In Vitro Techniques , Mitochondria, Heart/drug effects , Mitochondria, Heart/metabolism , Mitochondrial Membrane Transport Proteins/drug effects , Mitochondrial Permeability Transition Pore , Myocardial Reperfusion Injury/physiopathology , Potassium Channel Blockers/pharmacology , Potassium Channels/agonists , Rats , Rats, Wistar
8.
J Biol Regul Homeost Agents ; 27(3): 853-9, 2013.
Article in English | MEDLINE | ID: mdl-24152849

ABSTRACT

Although musculoskeletal disorders are the most frequent cause of occupational diseases in musicians, very few studies have focused attention on a single category of instruments, in particular on the violin. This involves, in its practice, almost all the areas of the body, besides being in the category of strings which is the most numerous in an orchestra. A specific protocol, investigating postural and clinical profiles of the musculoskeletal apparatus as well as job stress, was utilized in a conservatory on graduates in the tenth year of violin study, who regularly participated in activities of orchestras or string quartets. The investigation revealed target segments of osteoarticular apparatus (jaw, vertebral spine, shoulders, elbows, hands and fingers, lower limbs) electively subjected to overuse, as well as muscle contracture of trapezoids and hyperkeratosis of fingers and clavicle. Although the work environment was comfortable, most violinists claimed to undergo intense rhythms and competitiveness. This study, highlighting subclinical occupational diseases in young musicians (violinists) suggests adequate prevention measures.


Subject(s)
Musculoskeletal Diseases/etiology , Music , Occupational Diseases/etiology , Stress, Psychological/etiology , Adult , Biomechanical Phenomena , Humans
9.
J Physiol Sci ; 62(4): 333-41, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22614393

ABSTRACT

Ischemic postconditioning (IPOC) protects the myocardium from ischemic-reperfusion injury, improving functional recovery and cell viability. This protection is concurrent with stimulation of glycogen breakdown, increased mitochondrial ATP synthesis and content, maintenance of reduced-to-oxidized glutathione ratio (GSH/GSSG), and decreased oxidative damage. The present study's objective was to assess whether these effects are associated with increased resistance to mitochondrial permeability transition pore (MPTP) opening. The effects of the AMP-activated protein kinase (AMPK) inhibitor, compound C (CC), were measured to investigate association with AMPK. Mitochondria removed from postconditioned hearts required higher calcium levels to induce MPTP opening. Improved functional recovery, increased glycogen mobilization, maintenance of the GSH/GSSG ratio, decreased oxidative damage, and increased resistance to MPTP opening were abrogated when the hearts were postconditioned in the presence of CC, without affecting preservation of cell viability. Although AMPK appears to play a role in IPOC, it would not be the major cellular mediator.


Subject(s)
AMP-Activated Protein Kinases/antagonists & inhibitors , Ischemic Postconditioning , Mitochondria, Heart/drug effects , Mitochondrial Membrane Transport Proteins/physiology , Pyrazoles/pharmacology , Pyrimidines/pharmacology , Animals , Cell Survival/drug effects , Female , Glutathione/metabolism , Glutathione Disulfide/metabolism , Mitochondrial Permeability Transition Pore , Myocardial Reperfusion Injury/prevention & control , Oxidative Stress , Rats , Rats, Wistar
10.
J Frailty Aging ; 1(1): 32-8, 2012.
Article in English | MEDLINE | ID: mdl-27092935

ABSTRACT

OBJECTIVES: Objective measures of physical function are useful prognostic tools also for hospitalized elders. Low handgrip strength is predictive of poor outcomes and it can be assessed also in a sitting position, representing a potential alternative measure in bedridden patients. We evaluated grip strength prognostic value in hospitalized older patients. DESIGN: Prospective cohort study. SETTING: Geriatric, medical ward of an academic medical center in Ferrara, Italy. PARTICIPANTS: Patients aged 65 and older (N = 88) admitted to the hospital for an acute medical condition. MEASUREMENTS: Patients were evaluated for grip strength at hospital admission and were re-evaluated at discharge. After discharge, they were followed every 3 months for 1 year by telephone interviews to assess new hospitalizations and vital status. RESULTS: The mean age of the sample was 77.3 years, 47% were women. At admission, mean height standardized handgrip strength was 15.7±5 kg/m; men had greater strength (p<0.001). There was a direct relationship of admission grip strength with BMI (p<0.05), serum albumin (p=0.07), and Short Physical Performance Battery score (p<0.05), and an inverse relationship with age (gender-adjusted p value <0.01). In multiple regression analysis, after adjustment for possible confounders, patients in third tertile of grip strength had a shorter hospital stay compared to those in the first tertile (ß -2.8; p<0.05). Patients with higher grip strength at discharge also had a lower risk of rehospitalization or death over the follow-up, although the result was not statistically significant (OR: 0.68; 95% CI: 0.30-1.52). CONCLUSION: In older hospitalized medical patients, grip strength assessment might provide useful prognostic information.

11.
J Physiol Sci ; 61(4): 303-12, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21547611

ABSTRACT

The effects of ischemic-postconditioning (IPOC) on functional recovery and cell viability of ischemic-reperfused hearts from fed and fasted rats were studied in relation to triacylglycerol and glycogen mobilization, ATP content, glucose-6-phosphate dehydrogenase activity and reduced/oxidized glutathione (GSH/GSSG). Oxidative damage was estimated by measuring thiobarbituric acid reactive substances (TBARS). IPOC improved contractile recovery and cell viability in the fed but attenuated them in the fasted hearts. In both groups ischemia lowered glycogen. IPOC further reduced it. Triacylglycerol remained unchanged during ischemia-reperfusion in both groups, but triacylglycerol mobilization was activated by IPOC in the fasted group. ATP was increased by IPOC in the fed hearts, but lowered in the fasted ones, which appeared to be associated with the rates of ATP synthesis in isolated mitochondria. In the fed hearts IPOC raised glucose-6-phosphate dehydrogenase activity and GSH/GSSG, and lowered TBARS. These results suggest that IPOC effects are associated with changes in the ATP supply, mobilization of energy sources and glutathione antioxidant ratio.


Subject(s)
Energy Metabolism/physiology , Fasting/physiology , Heart/physiopathology , Ischemic Postconditioning , Myocardial Ischemia/physiopathology , Myocardial Reperfusion , Adenosine Triphosphate/metabolism , Animals , Blood Pressure/physiology , Cell Survival/physiology , Female , Glucosephosphate Dehydrogenase/metabolism , Glutathione/metabolism , Glutathione Disulfide/metabolism , Glycine/analogs & derivatives , Glycine/pharmacology , Glycogen/metabolism , Heart/drug effects , Heart Rate/physiology , Mitochondria, Heart/metabolism , Myocardial Contraction/physiology , Myocardial Ischemia/metabolism , Myocardial Reperfusion Injury/prevention & control , Myocardium/enzymology , Myocardium/metabolism , Myocardium/pathology , Myocytes, Cardiac/pathology , Rats , Rats, Wistar , Thiobarbituric Acid Reactive Substances/metabolism , Triglycerides/metabolism , Ventricular Dysfunction, Left/physiopathology
12.
G Ital Med Lav Ergon ; 32(4 Suppl): 328-30, 2010.
Article in Italian | MEDLINE | ID: mdl-21438291

ABSTRACT

Already by the enactment of D.P.R. 1124/65 Legislator has, de iure e de facto, carried out an interaction between INAIL and the Competent Doctor (once Factory Doctor). By the enactment of the new Consolidated Act about Safety, the synergy between D.P.R. 1124/65 and D.Lgs. 81/2008 and, consequently, between INAIL doctor and Competent Doctor has further been enhanced, laying the essential requirements, according to the AA.s for a greater and greater collaboration between the two professional figures, with the objective of a more and more caring guardianship of the worker's health in the occupational field.


Subject(s)
Occupational Health/legislation & jurisprudence , Occupational Medicine/legislation & jurisprudence , Humans , Italy
13.
Arch Physiol Biochem ; 112(1): 31-6, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16754201

ABSTRACT

To assess whether glycolysis, Na+-H+ exchange and oxidation of fatty acid derived from endogenous lipolysis are involved in the beneficial effects of 24-h fasting on the ischaemic - reperfused heart, it was studied the effects of inhibiting Na+ - H+ exchange using 10 muM dimethylamiloride and fatty acid oxidation using 2 mM oxfenicine, on the functional activity, lactate production and cell viability measured with tetrazolium stain. Since fasting accelerates heart fatty acid oxidation, data were compared to those from fed rats; using Langendorff perfused (glucose 10 mM) hearts of 250-350 g Wistar rats exposed to 25 min ischaemia - 30 min reperfusion. Fasting reduced the ischaemic rise of end diastolic pressure (contracture), improved recovery of contraction and lowered lactate production in comparison with the fed whereas cellular viability was similar in both groups. Dimethylamiloride improved the recovery of contraction (fed control 24 +/- 9%, fed treated 68 +/- 11%, P < 0.05 at the end of reperfusion), attenuated the contracture (fed control 40 +/- 9%, fed treated 24 +/- 11%, P < 0.05 at the beginning of reperfusion) and reduced lactate production in the fed group and increased cellular viability in both groups (fed control 21 +/- 6%, fed treated 69 +/- 7%, P < 0.05, and fasted control 18 +/- 7%, fasted treated 53 +/- 8%, P < 0.05). Oxfenicine reduced the recovery of contraction (fasted control 88 +/- 6%, fasted treated 60 +/- 11%, P < 0.05) and increased lactate production of fasted group and attenuated the contracture in the fed. These data suggest that beneficial effects of fasting owe, at least in part, to a lowered glycolysis probably secondary to the increased fatty acid oxidation and to the accumulation of energy supplying acyl esters. Dimethylamiloride slowing of glycolysis might explain functional improvement, whereas it seems unrelated to the protection on cell viability.


Subject(s)
Fasting/metabolism , Fatty Acids/metabolism , Glycolysis , Ion Transport , Myocardial Ischemia/metabolism , Amiloride/analogs & derivatives , Amiloride/pharmacology , Animals , Carnitine O-Palmitoyltransferase/antagonists & inhibitors , Cell Survival , Enzyme Inhibitors/pharmacology , Female , Glycine/analogs & derivatives , Glycine/pharmacology , In Vitro Techniques , Ion Transport/drug effects , Ion Transport/physiology , Ischemic Preconditioning, Myocardial , Lactic Acid/biosynthesis , Lipid Metabolism/drug effects , Male , Muscle Cells/pathology , Myocardial Contraction/drug effects , Myocardial Ischemia/pathology , Oxidation-Reduction , Rats , Rats, Wistar , Reperfusion Injury/metabolism
14.
J Physiol Biochem ; 61(3): 447-56, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16440599

ABSTRACT

This investigation aimed to assess whether the mitochondrial ATP-sensitive potassium channel blocker 5-hydroxydecanoate (5-HD) could abolish the protection conferred by fasting and ischemic preconditioning (IPC) and to ascertain whether these effects are associated with glycogen breakdown and glycolytic activity. Langendorff perfused hearts of fed and 24-h fasted rats were exposed to 25 min ischemia plus 30 min reperfusion. IPC was achieved by a 3 min ischemia plus a 5 min reperfusion cycle. 5-HD (100 microM) perfusion begun 5 min before IPC or 13 min before sustained ischemia in the non preconditioned groups. Fasting improved the reperfusion recovery of contraction, decreased the contracture and the lactate production, increased glycogenolysis and did not affect the percentage of viable tissue. 5-HD abolished the effects of fasting on the contractile recovery but did not affect the contracture. 5-HD decreased the lactate production in the fed group, increased the preischemic glycogen content in both nutritional groups and did not affect the ischemic glycogen fall. IPC improved the contractile function but prevented the contracture only in the fed group, reduced lactate accumulation and glycogenolysis and evoked an increase of the viable tissue. 5-HD abolished the effects of IPC on the contractile recovery and did not affect its effect on the contracture, lactate production, glycogenolysis and viable tissue. These data suggest that the mitocondrial ATP-sensitive potassium channel is involved in the effects of fasting and IPC on the contractile function but the other cardioprotective and metabolic effects appear evoked through other mechanisms. Also suggest that besides the inhibition of the mitochondrial potassium channel, other mechanisms mediate the effects of 5-HD.


Subject(s)
Decanoic Acids/pharmacology , Fasting , Heart/drug effects , Hydroxy Acids/pharmacology , Ischemic Preconditioning , Reperfusion Injury , Animals , Female , Male , Rats , Rats, Wistar
15.
J Physiol Biochem ; 60(1): 51-8, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15352384

ABSTRACT

This investigation aimed to assess whether the mitochondrial ATP-sensitive potassium channel opener diazoxide could reproduce the protection conferred by ischemic preconditioning and to ascertain whether its effects are associated with changes in glycogen breakdown and glycolytic activity. Hearts of fed and 24-h fasted rats were perfused with 10 mM glucose containing medium and exposed to 25 min no-flow ischemia plus 30 min reperfusion. Diazoxide (10 microM) perfusion was begun 10 min before ischemia and continued throughout the experiment. Fasting accelerated reperfusion recovery of contraction, reduced the post-ischemic contracture and decreased lactate accumulation during ischemia but had no effects on glycogen levels and cellular viability. Diazoxide, did not affect glycogen catabolism but improved reperfusion recovery of contraction. Furthermore, diazoxide reduced ischemic lactate accumulation and contracture amplitude only in the fed group whereas it improved cell viability in the fed and fasted groups. These data indicate that: 1) reduced lactate production which may attenuate myocyte acidification might explain, at least in part, the beneficial effects of diazoxide on mechanical function, although data obtained with the fasted rat hearts indicate that other mechanisms must be involved as well; 2) the reduction of lactate production occurring in the fed group, does not seem to be related to glycogenolysis; and 3) since diazoxide improved cell viability in the fasted rat group where it did not reduce glycolytic activity, other mechanisms may be responsible for this cytoprotective effect.


Subject(s)
Diazoxide/pharmacology , Fasting , Potassium Channels/drug effects , Reperfusion Injury/prevention & control , Animals , Female , Ischemic Preconditioning , Male , Rats , Rats, Wistar
16.
J Physiol Biochem ; 58(2): 95-101, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12435084

ABSTRACT

The investigation aimed to assess the effects of hypoxic preconditioning in right ventricle strips of fed and 24-h fasted rats, which display a fast fatty acid catabolism, and to ascertain whether these effects are associated with changes in the tissue levels of long-chain acylCoA and acyl carnitine and glycolytic activity. Strips were mounted isometrically in Krebs-bicarbonate solution with 10 mM dextrose and paced at 1 Hz. Strips were exposed to 30 min hypoxia and 60 min reoxygenation with or without a previous preconditioning cycle of 5 min hypoxia followed by a 10 min reoxygenation. During hypoxia the fasted rat strips underwent a greater contracture with respect to the fed group. Preconditioning reduced the contracture strength and accelerated the post-hypoxic recovery only in the fasted rat strips. Hypoxia evoked an increase in the acylCoA and acyl carnitine tissue-contents of the strips which reached higher levels in the fasted than in the fed rat groups. Preconditioning had no effects on the content of these metabolites. During hypoxia lactate output was lower in the fasted than in the fed rat strips and preconditioning abolished this decrease. These data suggest that the protective effects of hypoxic preconditioning occur in the heart tissue predisposed to the oxidation of fatty acid and can not be ascribed to changes in the accumulation of acylCoA and acyl carnitine but could be due, at least in part, to an activation of glycolysis.


Subject(s)
Carnitine/analogs & derivatives , Fasting/metabolism , Hypoxia/metabolism , Ischemic Preconditioning, Myocardial/methods , Myocardial Contraction/physiology , Myocardial Reperfusion Injury/prevention & control , Acyl Coenzyme A/chemistry , Acyl Coenzyme A/metabolism , Analysis of Variance , Animals , Carnitine/chemistry , Carnitine/metabolism , Heart Ventricles/metabolism , Lactic Acid/metabolism , Myocardial Reperfusion Injury/metabolism , Rats , Rats, Wistar
17.
Arch Physiol Biochem ; 110(3): 189-96, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12221519

ABSTRACT

The effects of fasting and ischemic preconditioning (IP) on heart function of Langendorff-perfused rat hearts exposed to 25 min global ischemia plus 30 min reperfusion (RP), were correlated with lactate release and tissue-levels of long-chain acyl carnitine (LCCa) and CoA (LCCoA). IP was achieved by a 3 min ischemia plus a 5 min reperfusion cycle. Creatine kinase leakage was measured to assess the extent of cardiac injury. Fasting reduced the ischemic-induced contracture, improved RP recovery of mechanical function, reduced lactate release and increased the end-ischemia LCCoA and LCCa levels. Both in the fed and the fasted rat hearts IP delayed the pacemaker depression, reduced the amplitude of ischemic contracture and improved the RP recovery of contraction. However, IP reduced creatine kinase and lactate release only in the fed rat hearts. IP had no effects on tissue LCCa and LCCoA in both groups. These data suggest that: 1) beneficial effects of fasting may be ascribed, at least in part, to a reduced lactate production which may attenuate ischemic myocyte acidification and to the accumulation of fatty acyl esters which would favour citric acid cycle replenishment during RP. 2) beneficial effects of IP could be in part explained by the reduction of lactate production in the fed group although data obtained with the fasted rat heart indicate that another mechanisms must also be involved in the effects of IP. 3) accumulation of LCCoA and LCCa is not involved in the noxious effects of ischemia as well as in the protection effected by IP.


Subject(s)
Food Deprivation , Heart/physiology , Ischemic Preconditioning, Myocardial , Reperfusion Injury , Animals , Carnitine/metabolism , Female , Male , Oxygen/metabolism , Rats , Rats, Wistar , Time Factors
18.
J Physiol Biochem ; 56(4): 321-8, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11321526

ABSTRACT

Hypoxic preconditioning (PC) was studied using rat atria set up isometrically in 10 mM dextrose medium and paced at 1 Hz, applying three different protocols wherein fed and 24-h fasted rats were used in protocols 1 and 2 and only the fed in protocol 3. In protocol 1, PC was achieved applying a 5 min hypoxia followed by 10 min of reoxygenation before the onset of a 60 min hypoxia and 60 min reoxygenation. In protocol 2 the 5 min and a posterior 45 min hypoxia were applied in the absence of dextrose whereas in the 10 min and 60 min reoxygenation periods dextrose was present. In protocol 3, two cycles of 5 min dextrose-free hypoxic periods were applied before the sustained hypoxia (dextrose-free) and reoxygenation periods (10 min and final 45 min, both in the presence of dextrose). In the control groups of all protocols, the equilibration periods were prolonged to compensate the duration of PC. In the control groups of protocols 1 and 2, the sustained hypoxia evoked greater disturbances of contractility and a smaller post-hypoxic recovery in the fasted than in the fed rat atria. In protocol 1, PC markedly reduced the rise in resting tension and improved the post-hypoxic recovery in the fasted rat atria whereas in the fed rat atria protective effects were small and brief. In protocol 2, PC evoked a small reduction of contracture only in the atria from fasted rats and in protocol 3, PC exacerbated the hypoxic disturbances. These data suggest that PC effects depend both on the severity of the PC stress and the sustained hypoxia; and that PC does not require coronary flow.


Subject(s)
Hypoxia/physiopathology , Ischemic Preconditioning, Myocardial , Myocardial Contraction/physiology , Myocardial Reperfusion Injury/physiopathology , Animals , Fasting/physiology , Heart Atria/physiopathology , In Vitro Techniques , Rats , Rats, Wistar
19.
J Physiol Biochem ; 55(1): 17-23, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10494656

ABSTRACT

The aim of the investigation was to assess whether adenosine would ameliorate the hypoxic-induced disturbances of the isolated atria and ventricular strips from fed and 24 h fasted rats. Adenosine 100-50 microM exerted negative inotropic and chronotropic effects on the aerobic atria whereas 10 microM was ineffective. During hypoxia the atria underwent a decline of the peak developed tension and pacemaker frequency. Adenosine 50 microM was detrimental for the performance of hypoxic atria whereas a 10 microM neither affected the fall of peak tension nor the post-hypoxic recovery. Adenosine 100 microM did not affect the peak developed tension of the aerobic ventricular strips. Under hypoxia the ventricular strips from fed and fasted rats exhibited a pronounced depression of their peak developed tension together with the development of a strong contracture and a partial recovery after reoxygenation, which attained a similar extent in both nutritional states. Lactate output during hypoxia was lower in the group of fasted rats. Adenosine 100 microM did not exhibit any effect on the ventricular functions and glycolytic activity in both experimental groups. Results suggests that adenosine has no beneficial effects on rat isolated atria and ventricular strips in hypoxic conditions


Subject(s)
Adenosine/pharmacology , Heart Atria/drug effects , Heart Ventricles/drug effects , Hypoxia/prevention & control , Oxygen/administration & dosage , Animals , Female , In Vitro Techniques , Male , Rats
20.
Arch Physiol Biochem ; 107(1): 22-6, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10455555

ABSTRACT

Under hypoxic conditions the atrial contents of long-chain acyl CoA (LCCoA) and long-chain acylcarnitine display a close correlation with the noxious effects of fasting on the atrial functions as well as with the amelioration effected by inhibitors of carnitine palmitoyltransferase I. These findings suggested that fatty acid oxidation was detrimental for the hypoxic atria. However, since changes of the LCCoA and LCCa levels which may occur together with the hypoxic disturbances attained under some other metabolic interventions had not been assessed yet, present investigation aimed to provide information about this issue. At the end of the prehypoxic equilibration period, all the treatments tested evoked a fall of the free-CoA levels whereas free-carnitine, LCCoA and LCCa remained unchanged. In the hypoxic atria, 4-pentenoate, an inhibitor of fatty acid beta-oxidation that also can be oxidized, did not change LCCoA and LCCa levels whereas the readily oxidizable pentanoate evoked a drop of LCCoA. These effects may be due to the trapping of CoA as the short-chain acyl esters of both substances. Since 4-pentenoate and pentanoate were noxious on the hypoxic atria even though they did not increase LCCoA and LCCa contents, it may be inferred that short-chain acyl esters might be deleterious during oxygen shortage. The exposure to 3-hydroxybutyrate, an oxidizable substrate whose availability increases during fasting, did not alter the LCCoA and LCCa contents, agreeing with the weak detrimental effects that it exerts on the hypoxic atria. On the other hand, insulin elicited a rise in the LCCoA and a fall in the LCCa contents. Inasmuch insulin had been shown to improve the performance of the hypoxic atria, these findings suggest that LCCoA might not be involved in the noxious effects of fatty acid oxidation whereas LCCa would be the major toxic catabolite.


Subject(s)
3-Hydroxybutyric Acid/pharmacology , Acyl Coenzyme A/metabolism , Carnitine/analogs & derivatives , Fatty Acids, Monounsaturated/pharmacology , Heart Atria/drug effects , Insulin/pharmacology , Oxygen/pharmacology , Pentanoic Acids/pharmacology , Aerobiosis , Animals , Carnitine/metabolism , Cell Hypoxia , Female , Heart Atria/metabolism , Male , Oxidative Stress , Rats , Rats, Wistar
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