RESUMEN
OBJECTIVE: An increasing number of robotic hysterectomies are being performed and the most common indication is fibroids. Fibroid uterus is common indication for hysterectomy for enlarged uteri. The role of robotic approach for complex pathologies as enlarged uterus is still debatable. The study aimed to analyze the feasibility of robotic hysterectomy in patients with enlarged uteri and the impact of uterine weight on surgical outcomes and on operative time length. PATIENTS AND METHODS: One hundred and thirty-eight patients who underwent robotic hysterectomy for benign indications at the 2nd Division of Obstetrics and Gynecology, Azienda Ospedaliero-Universitaria Pisana, University of Pisa were consecutively enrolled. RESULTS: Data of patients undergoing robotic surgery for benign indications were collected. Patients were stratified in two groups based on their uterine weight, to analyze the effective impact of uterine weight and dimension on surgical performance, operative time and postoperative outcomes. Conversion rate was 0%. Median uterine weight was 615 g (range 400-1900 g). Median total operating time was 131 minutes (range 70-255 minutes). Increase in uterine weight significantly increased operative times (p=0.003) and morcellation time (p=0.001). On the other hand, operative time was just partially influenced by route for removal of the uterus (p=0.085) but significantly affected by uterine weight (p=0.008), previous surgeries (p=0.003) and BMI of the patient (p=0.005). CONCLUSIONS: Robotic hysterectomy is feasible and safe for challenging cases as large uteri. This technique could enable patients with outsized uteri, not suitable for vaginal hysterectomy, to undergo minimally invasive surgery with excellent results. Larger studies to investigate and compare robotic with other surgical approaches for difficult hysterectomies are needed to confirm these data.
Asunto(s)
Laparoscopía , Leiomioma , Procedimientos Quirúrgicos Robotizados , Femenino , Humanos , Histerectomía/efectos adversos , Histerectomía Vaginal/efectos adversos , Histerectomía Vaginal/métodos , Laparoscopía/efectos adversos , Leiomioma/patología , Leiomioma/cirugía , Tamaño de los Órganos , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Procedimientos Quirúrgicos Robotizados/efectos adversos , Procedimientos Quirúrgicos Robotizados/métodos , Anomalías Urogenitales , Útero/anomalías , Útero/patología , Útero/cirugíaRESUMEN
OBJECTIVE: Cervical ectopic pregnancy (CEP) is a rare obstetric complication but carries the risk of life-threatening maternal hemorrhage. CASE PRESENTATION: A 43-year-old nulliparous woman, presented to the Emergency Room with vaginal bleeding. Initial quantitative serum ß-hCG value was 85,220 mIU/mL. Obstetrical ultrasound demonstrated a single, live pregnancy of approximately 9 weeks' gestation located within the endocervix. After discussing different management options, intramuscular methotrexate injection in association with intra-amniotic chloride potassium installation was decided in order to preserve patient's desire for childbearing. Three months later, the patient was readmitted due to a massive vaginal bleeding. Angiographic uterine artery embolization (UAE) with an absorbable gelatin sponge was performed. After the procedure and two days of hospitalization, no significative bleeding was observed. The clinical course was uneventful, and serum human chorionic gonadotropin decreased immediately. The cervical mass gradually shrank and disappeared a month after UAE. CONCLUSIONS: To preserve fertility in the management of CEP, clinicians could consider a combination of strategies, including UAE. A review of the current literature and possible treatment options for conservative CEP management are analyzed and discussed.
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Abortivos no Esteroideos/uso terapéutico , Preservación de la Fertilidad , Metotrexato/uso terapéutico , Embarazo Ectópico/tratamiento farmacológico , Abortivos no Esteroideos/administración & dosificación , Adulto , Femenino , Humanos , Inyecciones Intramusculares , Metotrexato/administración & dosificación , Embarazo , Embarazo Ectópico/diagnósticoRESUMEN
OBJECTIVE: Tigecycline is a glycylcycline antimicrobial structurally related to minocycline, with a wide spectrum of activity that includes anaerobes and typical and atypical microorganisms causing pelvic inflammatory disease (PID). This study aimed to evaluate efficacy and safety of tigecycline in complicated PID and un-complicated PID after the failure of first-line antibiotic therapy. PATIENTS AND METHODS: Between May 2014 and April 2016 at the 2nd Unit of Obstetrics and Gynecology, Santa Chiara Hospital of Pisa a pilot study on 20 women with mild/moderate PID after the failure of first-line antibiotic therapy and on 8 women with complicated PID was conducted. The treatment protocol was 10-day course of tigecycline, with a loading dose of 100 mg intravenously (i.v.) at day one and then 50 mg IV twice daily. The primary endpoint was to evaluate tigecycline's efficacy in terms of clinical response to test-of-cure (TOC) at the end of therapy and 30 days after the last dose. Clinical response during therapy and safety were analyzed as well. RESULTS: A total of 28 women were enrolled, and 25 patients completed the study protocol, because 3 patients reported adverse drug effects resulting in treatment interruption. PID was mainly caused by Chlamydia, Gardnerella, Mycoplasma/Ureaplasma. Tigecycline showed a 100% remission of signs and symptoms in patients resistant to first-line antibiotic regimen and in patients with complicated PID. Moreover, tigecycline showed good tolerability and compliance. CONCLUSIONS: Despite the limited sample size, tigecycline seemed an effective and safe treatment for women with complicated/resistant PID. Nevertheless, further clinical trials are needed to confirm these results.
Asunto(s)
Antibacterianos/uso terapéutico , Enfermedad Inflamatoria Pélvica/tratamiento farmacológico , Tigeciclina/uso terapéutico , Adulto , Antibacterianos/efectos adversos , Proteína C-Reactiva/análisis , Relación Dosis-Respuesta a Droga , Femenino , Gastritis/etiología , Humanos , Inyecciones Intravenosas , Persona de Mediana Edad , Náusea/etiología , Enfermedad Inflamatoria Pélvica/complicaciones , Enfermedad Inflamatoria Pélvica/patología , Proyectos Piloto , Inducción de Remisión , Índice de Severidad de la Enfermedad , Tigeciclina/efectos adversos , Adulto JovenRESUMEN
Myostatin (Mstn) is a skeletal muscle growth inhibitor involved in metabolic disorders and heart fibrosis. In this study we sought to verify whether Mstn is also operative in atherosclerosis of abdominal aorta. In human specimens, Mstn expression was almost absent in normal vessels, became detectable in the media of non-progressive lesions and increased with the severity of the damage. In progressive atherosclerotic lesions, Mstn was present in the media, neointima, plaque shoulder and in infiltrating macrophages. Mstn co-localized with α-smooth muscle actin (α-SMA) staining and with some CD45+ cells, indicating Mstn expression in VSMCs and bloodstream-derived leukocytes. In vitro, Mstn was tested in VSMCs and monocytes. In A7r5 VSMCs, Mstn downregulated proliferation and Smoothelin mRNA, induced cytoskeletal rearrangement, increased migratory rate and MCP-1/CCR2 expression. In monocytes (THP-1 cells and human monocytes), Mstn acted as a chemoattractant and increased the MCP-1-dependent chemotaxis, F-actin, α-SMA, MCP-1 and CCR2 expression; in turn, MCP-1 increased Mstn mRNA. Mstn induced JNK phosphorylation both in VSMCs and monocytes. Our results indicate that Mstn is overexpressed in abdominal aortic wall deterioration, affects VSMCs and monocyte biology and sustains a chronic inflammatory milieu. These findings propose to consider Mstn as a new playmaker in atherosclerosis progression.
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Aterosclerosis/metabolismo , Monocitos/citología , Músculo Liso Vascular/citología , Miostatina/genética , Miostatina/metabolismo , Actinas/metabolismo , Animales , Aorta Abdominal , Aterosclerosis/genética , Movimiento Celular , Proliferación Celular , Células Cultivadas , Proteínas del Citoesqueleto/genética , Progresión de la Enfermedad , Humanos , Monocitos/metabolismo , Proteínas Musculares/genética , Músculo Liso Vascular/metabolismo , Ratas , Células THP-1RESUMEN
Progressive supranuclear palsy (PSP) is a neurodegenerative disorder characterized by extensive neurofibrillary tangle (NFT) formation and neuronal loss in selective neuronal populations. Currently, no clues to the biological events underlying the pathological process have emerged. In Alzheimer disease (AD), which shares with PSP the occurrence of NFTs, advanced glycation end products (AGEs) as well as oxidation adducts have been found to be increased in association with neurofibrillary pathology. The presence and the amount of lipid and protein oxidation markers, as well as of pyrraline and pentosidine. 2 major AGEs, was assessed by biochemical, immunochemical, and immunocytochemical analysis in midbrain tissue from 5 PSP cases, 6 sporadic AD cases, and 6 age-matched control cases. The levels of 4-hydroxynonenal (HNE) and thiobarbituric acid reactive substances (TBARS), 2 major products of lipid peroxidation, were significantly increased by 1.6-fold (p < 0.04) and 3.9-fold (p < 0.01), respectively, in PSP compared with control tissues, whereas in AD only TBARS were significantly increased. In PSP tissue the intensity of neuronal HNE immunoreactivity was proportional to the extent of abnormal aggregated tau protein. The amount of protein oxidation products and AGEs was instead similar in PSP and control tissues. In AD, a higher but not significant level of pyrraline and pentosidine was measured, whereas the level of carbonyl groups was doubled. These findings indicate that in PSP, unlike in AD, lipid peroxidation is selectively associated with NFT formation. The intraneuronal accumulation of toxic aldehydes may contribute to hamper tau degradation, leading to its aggregation in the PSP specific abnormal filaments.
Asunto(s)
Peróxidos Lipídicos/metabolismo , Parálisis Supranuclear Progresiva/metabolismo , Anciano , Aldehídos/metabolismo , Enfermedad de Alzheimer/metabolismo , Arginina/análogos & derivados , Arginina/metabolismo , Productos Finales de Glicación Avanzada/metabolismo , Humanos , Inmunohistoquímica , Lisina/análogos & derivados , Lisina/metabolismo , Mesencéfalo/metabolismo , Persona de Mediana Edad , Norleucina/análogos & derivados , Norleucina/metabolismo , Pirroles/metabolismo , Valores de Referencia , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Proteínas tau/metabolismoRESUMEN
Oxidative damage of plasma proteins determined with the markers carbonyl group (CG) content and thiobarbituric acid-reactive substances (TBARS) was studied in 13 hemodialyzed and eight kidney-transplanted patients. The level of CGs was 38% higher in hemodialysis (HD) patients (1.49 +/- 0.05 nmol/mg protein) than in the healthy subjects (1.08 +/- 0.03 nmol/mg protein); the TBARS level was also higher in HD patients than in the control group (2.64 +/- 0.15 v 1.81 +/- 0.09 nmol/mL, P < .001). These data confirm that in end-stage renal failure, an increased oxidative stress is present and is able to induce protein damage. After transplantation, the CG content in protein was reduced (1.34 +/- 0.08 nmol/mg protein), but it was not significantly different from the level in the HD group. The failure to return to the normal range suggests that an impaired redox status is maintained, resulting in a sustained elevation of CG. Conversely, the level of TBARS in transplanted patients (1.99 +/- 0.22 nmol/mL) was not significantly different from that in the control group (1.81 +/- 0.09), suggesting that lipoperoxidation may be inhibited. These results may be explained by the different turnover rates of the molecules and by the distinct origin of the two markers, resulting from the damage of proteins or lipids. Thus, lipoperoxidation would produce rapidly removable molecules, whereas protein oxidation damage would tend to accumulate. However, the significant correlation found between CGs and TBARS indicates that a common cause (oxidative stress) binds the two markers of damage.
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Proteínas Sanguíneas/metabolismo , Trasplante de Riñón , Diálisis Renal , Femenino , Humanos , Peroxidación de Lípido , Masculino , Persona de Mediana Edad , Oxidación-Reducción , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Recent data suggest that protein glycation is involved in the process of amyloid formation in Alzheimer's disease (AD). To further investigate this issue, we analyzed the presence of advanced glycation end products (AGE) in soluble and insoluble forms of amyloid beta-protein (A beta) as well as in apolipoprotein E (apoE), a protein bound to amyloid deposits. Both proteins were extracted from cerebral cortex obtained from patients with AD and probed by immunoblotting with two antibodies specific for different AGE, already known to immunocytochemically label amyloid plaques. All the AGE antibodies failed to recognize either A beta or apoE, whereas they reacted with synthetic A beta glycated in vitro. These findings indicate that other proteins associated with amyloid deposits are candidates to be modified with AGE in Alzheimer's cerebral tissue.
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Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Corteza Cerebral/metabolismo , Lipoproteínas LDL/metabolismo , Péptidos beta-Amiloides/química , Anticuerpos , Química Encefálica , Corteza Cerebral/química , Productos Finales de Glicación Avanzada/análisis , Glicosilación , Humanos , Immunoblotting , Lipoproteínas LDL/químicaRESUMEN
In order to study the role of oxidative stress in celiac disease, protein carbonyl groups, thiobarbituric acid-reactive substance and pentosidine were evaluated in the plasma of nine patients with asymptomatic celiac disease and in a control group (n = 25). Plasma alpha-tocopherol, retinol and lipids were determined in the same samples. The levels of markers of oxidative stress derived from both protein (carbonyl groups) and lipids (thiobarbituric acid-reactive substances) were significantly higher in celiac disease patients, whereas lipoproteins and alpha-tocopherol were significantly lower. These data indicate that in celiac disease, even when asymptomatic, a redox imbalance persists; this is probably caused by an absorption deficiency, even if slight. Dietary supplementation with antioxidant molecules may offer some benefit and deserves further investigation.
Asunto(s)
Proteínas Sanguíneas/análisis , Enfermedad Celíaca/metabolismo , Estrés Oxidativo , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis , Vitamina E/sangre , Adolescente , Adulto , Arginina/análogos & derivados , Arginina/sangre , Proteínas Sanguíneas/química , Estudios de Casos y Controles , Femenino , Humanos , Lípidos/sangre , Lisina/análogos & derivados , Lisina/sangre , Masculino , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Vitamina A/sangreRESUMEN
Carbonyl groups result from protein oxidation and their level in tissues and plasma is a relatively stable marker of oxidative damage. Carbonyl content of plasma proteins in 43 type 2 diabetic subjects, 30-87 years of age (25 males and 18 females) and in 20 age-matched healthy controls (31-89 years of age, 12 males and 8 females) was evaluated with 2,4-dinitro-phenyl-hydrazine method. In both groups, lipids, tocopherols (HPLC) and glycated hemoglobin (HPLC) were studied. Fasting blood glucose, glycated hemoglobin and lipids were significantly higher in the diabetic group; carbonyl content and alpha-tocopherol were slightly, but not significantly higher in the diabetic group (1.06 +/- 0.03 vs. 0.97 +/- 0.04 nmol/mg protein, 27. 07 +/- 2.82 vs. 31.55 +/- 2.11 micromol/l, respectively). Significant relationships between age and lipids, alpha-tocopherol and proteins were found in controls, but not in diabetics. Alpha-tocopherol correlated with lipids in both groups; glycated hemoglobin, a marker of glycemic control, was related to lipids, alpha-tocopherol and protein carbonyl groups in diabetics, while only the correlation with carbonyls was found in controls. These results suggest that impaired glycemic control is connected to protein oxidation. Glycation cascade also releases free radicals, becoming responsible for further oxidative attacks. In conclusion, increased oxidative stress, if any, in the diabetic group, is doubtlessly induced by hyperglycemia, and the tocopherols are not seriously affected by a worsening of the metabolic control.
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Proteínas Sanguíneas/análisis , Proteínas Sanguíneas/química , Diabetes Mellitus Tipo 2/sangre , Glicoproteínas , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Colesterol/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxidación-Reducción , Valores de Referencia , Análisis de Regresión , Triglicéridos/sangre , Vitamina E/sangre , Proteínas Séricas GlicadasRESUMEN
BACKGROUND: Oxidative stress is an important process that occurs in vivo during aging and is considered one of the main causes of molecular damage to cellular and tissue structures. These changes can accumulate in biological structures during aging. OBJECTIVE: The aim of this work is to evaluate plasma protein oxidative damage, measured as carbonyl groups content, and the concentration of some antioxidant molecules (vitamins and carotenoids) in 122 healthy volunteers (50 males and 72 females), 25 to 89 years old. RESULTS: Total plasma proteins slightly decreased with age, but the level of carbonyl groups was similar in the adult (< 65 years) and in the old, and was similar in both sexes. Plasma concentration of antioxidant molecules such as alpha-tocopherol, beta-carotene and other carotenoids, increased with age and correlated with the level of lipoproteins; plasma total cholesterol and triglycerides were significantly correlated with age as well. CONCLUSIONS: The surprisingly normal level of plasma protein carbonyl groups in our older subjects suggests two possibilities: a) the older people in our study are healthy and free from pathologies because of better protection against oxidative injury during their lifetimes, i.e., they maintained low-level oxidative damage on plasma proteins; or b) the level of carbonyl groups is normal because of the high turnover in plasma: the oxidized circulating proteins are preferentially and quickly removed; in this case oxidative damage is not discernible in plasma proteins but may proceed silently in other tissues.
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Envejecimiento/fisiología , Antioxidantes , Proteínas Sanguíneas/metabolismo , Carotenoides/sangre , Colesterol/sangre , Hidrazonas/sangre , Estrés Oxidativo/fisiología , Tocoferoles/sangre , Triglicéridos/sangre , Vitamina A/sangre , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de ReferenciaRESUMEN
Classical textbooks and recent publications about the anatomy of the dorsal cutaneous branch of the ulnar nerve are revisited and correlated with methods of measurement of its conduction velocity, in order to evaluate the indications and limitations of the procedure. Etiology and pathogenesis of isolated lesions of this nerve branch are discussed.
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Mano/inervación , Conducción Nerviosa/fisiología , Nervio Cubital/anatomía & histología , Electrofisiología , Humanos , Nervio Cubital/fisiología , Neuropatías Cubitales/diagnósticoAsunto(s)
Hemangioma Cavernoso/cirugía , Hepatectomía , Histerectomía Vaginal , Laparoscopía , Leiomioma/cirugía , Neoplasias Hepáticas/cirugía , Procedimientos Quirúrgicos Robotizados , Neoplasias Uterinas/cirugía , Pérdida de Sangre Quirúrgica/prevención & control , Índice de Masa Corporal , Femenino , Hepatectomía/métodos , Humanos , Histerectomía Vaginal/métodos , Laparoscopía/métodos , Persona de Mediana Edad , Tamaño de los Órganos , Factores de Riesgo , Procedimientos Quirúrgicos Robotizados/métodos , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND: Progestins have actions on the cardiovascular system, which depend on the structure as well as on receptor binding characteristics. Drospirenone (DRSP) is a progestin that uniquely interferes with the signaling of the mineralocorticoid receptor (MR). Hormone therapy containing DRSP results in blood pressure reduction in hypertensive post-menopausal women. METHODS: We describe the effects of DRSP on endothelial nitric oxide (NO) synthesis and compare them with those of progesterone (P) and of medroxyprogesterone acetate (MPA). In addition, we herein tested the relevance of the anti-mineralocorticoid activity of DRSP for NO synthesis. RESULTS: DRSP results in rapid activation of the endothelial NO synthase (eNOS) through mitogen-activated protein kinases and phosphatidylinositol 3-kinase as well as in enhanced eNOS expression. These actions depend on P receptor. When the cells are exposed to aldosterone, a reduction of eNOS expression is found that is antagonized by DRSP. This action is not shared by P or MPA. In addition, DRSP does not interfere with the induction or activation of eNOS induced by estradiol, as opposed to MPA. CONCLUSIONS: DRSP acts on endothelial cells via a combined action through the P and MRs. These results help to interpret the anti-hypertensive effects of hormonal therapies containing DRSP.
Asunto(s)
Androstenos/farmacología , Óxido Nítrico Sintasa de Tipo III/metabolismo , Receptores de Mineralocorticoides/efectos de los fármacos , Receptores de Progesterona/efectos de los fármacos , Aldosterona/farmacología , Androstadienos/farmacología , Células Cultivadas , Endotelio Vascular/citología , Activación Enzimática , Estradiol/farmacología , Flavonoides/farmacología , Humanos , Acetato de Medroxiprogesterona/farmacología , Mifepristona/farmacología , Óxido Nítrico/biosíntesis , Óxido Nítrico Sintasa de Tipo III/efectos de los fármacos , Progesterona/farmacología , Transducción de Señal/efectos de los fármacos , Factores de Tiempo , WortmaninaRESUMEN
Free radical oxidation has been claimed as one of the most important mechanism of damage in aging and in several diseases. Carbonyl content in tissue and circulating proteins is a stable marker of this attack. In 29 apparently healthy subjects (25-89 years old) carbonyl content of plasma proteins and retinol and tocopherols (alpha- and gamma-) were studied. Carbonyls level did not show an increase with age. A good correlation between carbonyls content and gamma-tocopherol (r = 0.44, P < 0.05) and a trend with retinol (r = 0.34, P = 0.07) was found, but not with alpha-tocopherol. An inverse correlation was observed between carbonyls and plasma proteins (r = -0.63, P < 0.01) and the natural antioxidant studied showed an increase with age and a good relationship with lipids. These data suggest that retinol and tocopherols, well known scavengers of free radicals, are involved, at least partially, in the prevention of oxidative damage of circulating proteins.
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Proteínas Sanguíneas/metabolismo , Carbono/sangre , Oxígeno/sangre , Vitamina A/sangre , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/sangre , Colesterol/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Triglicéridos/sangre , Vitamina E/sangreRESUMEN
BACKGROUND: Concern exists in literature about the clinical course, the best acute and chronic treatment and the prognosis of idiopathic neonatal atrial flutter. The aim of our study was to evaluate this in a population of our patients with this type of arrhythmia. METHODS: Six infants (3 M, 3 F, mean age 42 +/- 62 days, range 1-150) affected with atrial flutter without structural heart disease were studied and then acutely and chronically treated. The effectiveness of chronic antiarrhythmic treatment was evaluated with Holter monitoring every 3 months for the first year of life and with transesophageal atrial pacing. RESULTS: Mean arrhythmia cycle length was 180 +/- 34 ms with atrioventricular conduction ratio ranging between 1:1 and 3:1. Two patients with clinical signs of heart failure were successfully treated with DC shock. Transesophageal overdrive atrial pacing was successfully used in one patient treated with i.v. propafenone without benefit. In the remaining three patients, cardioversion was achieved with amiodarone after digoxin had failed in all three and propafenone had failed in two of them. To prevent recurrences, we treated four patients with amiodarone, one with amiodarone combined with propranolol and one with digoxin. During the follow-up (22 +/- 11 months), neither arrhythmia recurrences nor side-effects of the therapy occurred. CONCLUSIONS: Neonatal atrial flutter is an arrhythmia with significant acute morbidity but an excellent long-term prognosis. Electrical cardioversion is the first-choice treatment when the arrhythmia is not well-tolerated hemodynamically, while class III antiarrhythmic drugs such as amiodarone should be preferred in the other cases.
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Aleteo Atrial/fisiopatología , Amiodarona/uso terapéutico , Antiarrítmicos/uso terapéutico , Aleteo Atrial/diagnóstico , Aleteo Atrial/terapia , Estimulación Cardíaca Artificial , Cardioversión Eléctrica , Electrocardiografía , Femenino , Humanos , Lactante , Recién Nacido , Masculino , PronósticoRESUMEN
The collagen structure of young and old rats was examined using a scanning force microscope (SFM). Rat tail tendons of 8- and 24-month-old Wistar rats were frayed by two blades and examined using a Nanoscope III SFM. In the same tendons, the pentosidine concentrations, a marker of the Maillard reaction, were determined by HPLC. The SFM inspection of native fibrils produces images of collagen bundles, with parallel fibrils. The diameters of old rat collagen fibrils were large in comparison to the young ones. Moreover, fibrils obtained from old rats exhibited the same band interval, while the depth of the gap between two overlap zones showed a higher mean value with respect to young collagen. The pentosidine concentration was also higher in the old than in the young tendons. In conclusion, in the presence of an increased concentration of advanced glycation end products, significant structural alterations have been observed in old fibrils.
Asunto(s)
Envejecimiento/fisiología , Colágeno/fisiología , Productos Finales de Glicación Avanzada/fisiología , Envejecimiento/metabolismo , Animales , Arginina/análogos & derivados , Arginina/metabolismo , Colágeno/ultraestructura , Productos Finales de Glicación Avanzada/metabolismo , Lisina/análogos & derivados , Lisina/metabolismo , Masculino , Microscopía/métodos , Concentración Osmolar , Periodicidad , Ratas , Ratas Wistar , Cola (estructura animal) , Tendones/metabolismoRESUMEN
BACKGROUND: The main functional property of collagen is to provide a supporting framework to almost all tissues: the effects of non-enzymatic glycation on this protein are deleterious and in diabetes mellitus contribute to the mechanism of late complications. The aim of this work is to provide evidence by scanning force microscopy of modifications in collagen structure caused by high glucose concentration, in vivo and in vitro, and to correlate the data with markers of non-enzymatic glycation. METHODS: Tendon fibrils were obtained from the tails of 8-month-old rats (BB/WOR/MOL¿BB) which developed diabetes spontaneously at least 12 weeks before they were killed, and from diabetes-resistant rats of the same strain (BB/WOR/MOL¿WB). A scanning force microscope (SFM; Nanoscope III) equipped with a Contact Mode Head was used for imaging. Band interval, diameter and depth of D-band gap were measured in non-diabetic and diabetic tail tendon fibrils and in fibrils incubated with glucose (0.5 M for 2 weeks). Fructosamine was determined in the tendon fibrils by a colorimetric method and pentosidine was evaluated in acid-hydrolyzed samples by coupled reverse phase-ionic exchange column HPLC. RESULTS: Incubated fibrils revealed modifications in radius (228+/-5 nm) and gap depth (3.65+/-0.10 nm) that closely reproduce diabetes-induced damage (236+/-3 and 3.20+/-0.04 nm respectively) and were significantly different from the pattern seen in non-diabetic fibrils (151+/-1 and 2.06+/-0.03 nm; p<0.001). Both fructosamine and pentosidine were higher in diabetic (3.82+/-1.43 nmol/mg and 2.23+/-0.24 pmol/mg collagen respectively) and in glucose-incubated fibrils (9.27+/-0.55 nmol/mg and 5.15+/-0.12 pmol/mg collagen respectively) vs non-diabetic tendons (1.29+/-0.08 nmol/mg and 0.88+/-0.11 pmol/mg collagen respectively; p<0.01); during the time course of incubation, an early increase in fructosamine was seen, whereas pentosidine increased later. The D-band parameter was similar in all three groups, indicating that axial organization is not modified by non-enzymatic glycation. CONCLUSION: This is the first description obtained with SFM of diabetes-induced ultrastructural changes in collagen fibrils. Moreover, the data presented are consistent with the concept that chronic exposure of collagen to glucose in vivo or in vitro leads to similar structural modifications in collagen fibrils, probably through crosslinks. The correlation between morphologic parameters and both markers of glycation provides strong evidence for a crucial role of this non-enzymatic modification.
Asunto(s)
Colágeno/química , Colágeno/ultraestructura , Diabetes Mellitus Tipo 1/patología , Tendones/química , Animales , Arginina/análogos & derivados , Arginina/análisis , Diabetes Mellitus Tipo 1/fisiopatología , Fructosamina/análisis , Productos Finales de Glicación Avanzada/análisis , Glicosilación , Lisina/análogos & derivados , Lisina/análisis , Masculino , Microscopía de Fuerza Atómica/métodos , Ratas , Ratas Endogámicas BB , Valores de Referencia , Tendones/ultraestructuraRESUMEN
In Down's syndrome, the presence of three copies of chromosome 21 is associated with premature aging and progressive mental retardation sharing the pathological features of Alzheimer disease. Early cortical dysgenesis and late neuronal degeneration are probably caused by an overproduction of amyloid beta-peptide, followed by an increased cellular oxidation. Interestingly, chromosome 21 codes for superoxide-dismutase and amyloid beta precursor resulting, in Down's syndrome, in an overflow of these gene products and metabolites. We studied Down's fetal brain cortex to evaluate the presence and amount of lipid and protein oxidation markers; moreover, we quantified two forms of glycation end products that are known to be involved in the process of cellular oxidation. All these parameters are significantly increased in Down's fetal brains in comparison to controls, providing the evidence that accelerated brain glycoxidation occurs very early in the life of Down's syndrome subjects.
Asunto(s)
Encéfalo/embriología , Encéfalo/metabolismo , Síndrome de Down/metabolismo , Estrés Oxidativo , Aldehídos/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Arginina/análogos & derivados , Arginina/metabolismo , Corteza Cerebral/embriología , Corteza Cerebral/metabolismo , Edad Gestacional , Productos Finales de Glicación Avanzada , Glicosilación , Humanos , Peroxidación de Lípido , Lisina/análogos & derivados , Lisina/metabolismo , Norleucina/análogos & derivados , Norleucina/metabolismo , Oxidación-Reducción , Pirroles/metabolismo , Superóxido Dismutasa/metabolismo , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismoRESUMEN
BACKGROUND: Progression of heart failure is associated with interstitial changes in the heart and in areas distant from the heart. Enhanced expression of metalloproteinases 2 and 9 and of metalloproteinases tissue inhibitors 1 and 2 have been found in ventricular tissue of patients with heart failure. Our aim was to determine whether increased activity of metalloproteinase-2, metalloproteinase-9 and of metalloproteinases tissue inhibitor-1 and metalloproteinases tissue inhibitor-2 were also present in plasma of patients with heart failure. DESIGN: Levels of metalloproteinase-2, metalloproteinase-9 and of metalloproteinase tissue inhibitor-1 and metalloproteinases tissue inhibitor-2 were measured in venous blood of 51 patients with heart failure, and were compared with levels of 52 control subjects. Samples collected from patients and control subjects were assayed for gelatinolytic activity (zymography) and for protein levels. RESULTS: Compared with the control subjects, the patients with heart failure had a significant increase in activity levels (mean +/- SE, ng mL(-1)) of prometalloproteinase-9 (95.1+/-11.2 and 38.9+/-4.5*), activ. metalloproteinase-9 (18.4+/-2.5 and 10.9+/-1.3*), and of prometalloproteinase-2 (571.4+/-26.1 and 456.8+/-21.1*) (respectively: patients and control subjects; *P<0.05). Metalloproteinases tissue inhibitor-1, but not metalloproteinases tissue inhibitor-2 protein values were higher in the patients. Among the patients, clinical status and New York Heart Association (NYHA) class did not correlate with the metalloproteinase concentrations. Positive correlations with left ventricular volumes, and negative correlations with lipid values were obtained for prometalloproteinase-2; positive correlations with total number of white cells and neutrophils were obtained for prometalloproteinase-9; and positive correlations with lactate dehydrogenase, serum fibrinogen, aspartate transaminases were found for activ. metalloproteinase-9. CONCLUSIONS: Regardless of the clinical phase of heart failure, elevated levels of activity and of circulating metalloproteinase protein levels suggest the presence of persistent extracellular remodeling in patients with heart failure.