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1.
Acta biol. colomb ; 27(1): 131-134, ene.-abr. 2022. tab
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1360058

ABSTRACT

RESUMEN La dispersión de semillas por reptiles (saurocoría) ha recibido atención recientemente y se ha reportado el consumo de frutos y semillas en cocodrilianos, actuando como potenciales dispersores de semillas. Evaluamos si la saurocoría en Crocodylus actus y C. moreletii afecta la viabilidad de tres especies de plantas Delonixregia, Inga sp. y Citrullus lanatus. Se Utilizaron tres individuos juveniles de cada especie de cocodrilo y se alimentaron con 22 semillas por especie de planta, para un total de 66 semillas por recinto (132 para ambos). Las semillas se mezclaron con la dieta habitual cada semana, las semillas no consumidas y las excretadas se recolectaron y sembraron en suelo tratado con composta para evaluar la tasa de germinación relativa. Un total de 99 semillas fueron consumidas pero solo se recuperaron de las heces 14 semillas de C. lanatus, y germinando solo una de ellas (7, 14 %) con respecto al 50 % en el grupo control. Los resultados indican que la saurocoría de C. acutus y C. moreletii tiene un efecto negativo sobre la viabilidad de las semillas de las especies vegetales estudiadas, concordando con otros estudios realizados en diferentes especies.


ABSTRACT Seed dispersal by reptiles (saurochory) has recently received attention, and the consumption of fruits and seeds has been reported in crocodilians despite being mainly carnivores, acting as potential seed dispersers. We evaluate whether saurochory by Crocodylus acutus and C. moreletii affect the seed viability of three species of plants (Delonix regia, Inga sp., and Citrullus lanatus). We performed feeding trials, using three juvenile individuals of each species of crocodile, and fed them 22 seeds per plant species for a total of 66 seeds per enclosure (132 for both species). Seeds were combined with the usual diet each week. The unconsumed and excreted seeds were collected and planted in soil treated with compost to evaluate the relative germination rate. A total of 99 seeds were consumed, of which only 14 seeds of C. lanatus were recovered from the faeces, and only one of those germinated (7.14 %) with respect to 50 % in the control group. The results indicate that saurochory by C. acutus and C. moreletii has a negative effect on seed viability and germination of the plant species studied, as found in other studies using different species.

2.
Immunology ; 143(4): 578-87, 2014 Dec.
Article in English | MEDLINE | ID: mdl-24943111

ABSTRACT

Hepatitis A virus (HAV) infection is the major cause of acute liver failure in paediatric patients. The clinical spectrum of infection is variable, and liver injury is determined by altered hepatic enzyme function and bilirubin concentration. We recently reported differences in cytokine profiles between distinct HAV-induced clinical courses, and bilirubin has been recognized as a potential immune-modulator. However, how bilirubin may affect cytokine profiles underlying the variability in the course of infection has not been determined. Herein, we used a transcription factor (TF) binding site identification approach to retrospectively analyse cytokine expression in HAV-infected children and to predict the entire set of TFs associated with the expression of specific cytokine profiles. The results suggested that modulation of the activity of signal transducers and activators of transcription proteins (STATs) may play a central role during HAV infection. This led us to compare the degree of STAT phosphorylation in peripheral blood lymphoid cells (PBLCs) from paediatric patients with distinct levels of conjugated bilirubin (CB). Low CB levels in sera were associated with increased STAT-1 and STAT-5 phosphorylation. A positive correlation was observed between the serum interleukin-6 (IL-6) content and CB values, whereas higher levels of CB correlated with reduced serum IL-8 values and with a reduction in the proportion of PBLCs positive for STAT-5 phosphorylation. When CB was used to stimulate patients' PBLCs in vitro, the levels of IL-6 and tumour necrosis factor-α were increased. The data showed that bilirubin plays a role in STAT function and affects cytokine profile expression during HAV infection.


Subject(s)
Bilirubin/metabolism , Cytokines/metabolism , Hepatitis A virus , Hepatitis A/metabolism , STAT Transcription Factors/metabolism , Bilirubin/blood , Case-Control Studies , Child , Child, Preschool , Cluster Analysis , Cytokines/blood , Female , Hepatitis A/immunology , Hepatitis A virus/immunology , Humans , Leukocytes, Mononuclear/metabolism , Male , NF-kappa B/metabolism , Patient Outcome Assessment , Phosphorylation
3.
Article in English | MEDLINE | ID: mdl-12600674

ABSTRACT

Sexual dimorphism in potassium content was found in plasma, kidney, heart and skeletal muscle of CD1 mice. We observed that feeding mice with a K(+)-deficient diet had an uneven and gender-dependent effect on organ weight and tissue potassium concentrations. Treatment produced a marked decrease in plasma, pancreas and skeletal muscle K(+) levels in both sexes, and a reduction in kidney, liver and heart potassium concentrations in females. Moreover, K(+) deficiency produced a 2-3-fold increase in the concentrations of cationic amino acids, such as arginine and lysine in both heart and skeletal muscle of the two sexes, a slight increase ( approximately 37%) in renal arginine in the male mice. The concentrations of these amino acids in plasma and other tissues in both sexes remained unaltered. Polyamine levels in heart, liver, skeletal muscle and pancreas from male and female mice were not affected by K(+) deficiency. However, in the male kidney potassium deficiency was accompanied by an increase of putrescine and spermidine concentration, and a reduction of putrescine excretion into the urine, even though renal K(+) concentration was not significantly affected and ornithine decarboxylase activity was dramatically decreased. The general lack of correlation between tissue potassium decrease and the increase in organic cations suggests that it is unlikely that the changes observed could be related with an attempt of the tissues to compensate for the reduction in cellular positive charge produced by the fall in K(+) content. The mechanisms by which these changes are produced are discussed, but their physiological implications remain to be determined.


Subject(s)
Amino Acids/metabolism , Polyamines/metabolism , Potassium Deficiency/physiopathology , Potassium/metabolism , Amino Acids/blood , Animals , Body Composition , Body Weight , Female , Kidney/metabolism , Liver/metabolism , Male , Mice , Muscle, Skeletal/metabolism , Myocardium/metabolism , Pancreas/metabolism , Polyamines/blood , Potassium/administration & dosage , Potassium/blood , Potassium Deficiency/blood , Potassium, Dietary/administration & dosage , Potassium, Dietary/pharmacology , Sex Characteristics
4.
Res Exp Med (Berl) ; 199(4): 195-206, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10743677

ABSTRACT

Weanling rats fed a methyl-deficient diet develop acute renal failure, the morphological features of which vary from focal tubular necrosis to widespread cortical necrosis. We and others have shown that coconut oil, rich in saturated fatty acids, has a renal protective effect in this experimental model. In the experiment we are reporting now, we studied which fatty acid is involved in the protection afforded by coconut oil by feeding five groups of methyl-deficient rats a mixture of corn oil and hydrogenated vegetable oil, C6-C8-C10 fatty acids, C12 fatty acid, C14 fatty acid and C16-C18 fatty acids. Five groups of rats receiving the same diets supplemented with choline chloride were used as controls. The group of methyl-deficient rats fed C14 fatty acid (myristic acid) showed a greater percentage of surviving animals and lower renal damage than the other groups of methyl-deficient rats, indicating that the protective effect of coconut oil found in previous experiments is due to its high content of myristic acid.


Subject(s)
Choline Deficiency/complications , Diet , Kidney Cortex Necrosis/prevention & control , Myristic Acid/pharmacology , Analysis of Variance , Animals , Body Weight , Choline Deficiency/pathology , Creatinine/blood , Kidney Cortex Necrosis/etiology , Kidney Cortex Necrosis/pathology , Male , Organ Size , Rats , Rats, Wistar , Urea/blood
5.
Kidney Blood Press Res ; 21(5): 329-34, 1998.
Article in English | MEDLINE | ID: mdl-9851320

ABSTRACT

The aim of this study was to investigate whether the renoprotective effect of angiotensin-converting enzyme inhibitors (ACEIs) following 5/6 renal mass reduction is due in part to the potentiation of kinins. Three groups of rats with 5/6 renal mass reduction were studied during the 14 weeks following surgery. One group received no therapy (control); the second group was treated from the beginning with the ACEI ramipril (1 mg/kg/day) added to the drinking water, and the last group received ramipril plus a beta2-bradykinin antagonist, HOE 140 (500 microg/kg/day) via osmotic minipumps. Plasma creatinine did not change in any group during the study. Urinary protein excretion rose in the controls from 9.18+/-1.6 to 45.0+/-5.6 mg/24 h at the end of the study. In ramipril group proteinuria was prevented (initial 7.5+/-1.0 and final 8.6+/-0.8 mg/24h). The effect of ramipril was abolished by HOE 140 (initial 11.6+/-2.0 and final 38.9+/-11 mg/ 24 h). The systolic blood pressure of the controls increased from 106+/-2 to 144+/-5 mm Hg at the 14th week. Ramipril abolished the increase in systolic blood pressure. The effect of ramipril was reverted by HOE 140 (initial 108+/-2 and final 140+/-9 mmHg). Control rats had more severe histopathologic changes. Those animals receiving ramipril + HOE 140 displayed less severe glomerular changes, while rats treated only with ramipril had mild alterations. Thus the glomerular injury score was 2.11+/-0.32 for controls, 1.53+/-0.52 for rats treated with ramipril + HOE 140, and 0.06+/-0.04 for rats treated only with ramipril. The glomerular area was 20,886+/-1,410, 19,693+/-2,200 and 14,352+/-3,200 microm2, respectively, for the 3 groups. These results suggest that the protective effect of ACEIs in the development of chronic renal failure is partially mediated by kinins.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/administration & dosage , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Bradykinin/analogs & derivatives , Kidney Failure, Chronic/drug therapy , Kidney Failure, Chronic/metabolism , Kinins/metabolism , Ramipril/administration & dosage , Administration, Oral , Animals , Blood Pressure/drug effects , Bradykinin/administration & dosage , Kidney Failure, Chronic/physiopathology , Rats
6.
Brain Res Bull ; 45(2): 153-6, 1998.
Article in English | MEDLINE | ID: mdl-9443832

ABSTRACT

Several evidences support the hypothesis that central catecholamines may play a significant role in the production and/or maintenance of different alterations that characterize portal hypertension. The aim of the present work was to study the possible modifications in norepinephrine (NE) metabolism in several telencephalic and diencephalic areas rich in NE in experimental prehepatic portal hypertension. NE uptake was studied as an index of NE metabolism. The experiments were carried out in vitro in encephalic areas and nuclei, obtained according to the punch-out technique. Results indicated that portal hypertensive rats showed an enhancement of NE uptake in olfactory bulb (OB), preoptic area (PA), and supraoptic, periventricular, paraventricular, and arcuate nuclei (SON, PeVN, PaVN, and AN, respectively) compared to sham-operated rats. However, no modifications on NE uptake was observed in the median eminence (ME). Present results suggest that the changes observed in central NE uptake may be related to the development and/or maintenance of the portal hypertensive state.


Subject(s)
Basal Ganglia/metabolism , Diencephalon/metabolism , Hypertension, Portal/metabolism , Norepinephrine/metabolism , Telencephalon/metabolism , Animals , Blood Pressure/physiology , Male , Rats , Rats, Wistar
7.
Gastrointest Endosc ; 46(2): 131-8, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9283862

ABSTRACT

BACKGROUND: The compositional nature of the pigment of melanosis coli is essentially unknown. Previous histochemical studies suggested that this pigment has certain similarities with lipofuscin (i.e., age-dependent pigment) and ceroids (i.e., pathologically derived pigments) and that it may contain, therefore, polymerized glycolipids and glycoproteins. However, the saccharide composition of this pigment was never explored by lectin histochemical procedures, which was the main object of this study. METHODS: Colonoscopic biopsy specimens from eight patients with melanosis coli and from three normal control subjects were studied by fluorescent microscopy and by standard and lectin histochemistry. The number of apoptoses in the lining colonic epithelium was also evaluated histologically. RESULTS: Apoptotic bodies were significantly more numerous in patients with melanosis coil than in control subjects. The pigment that accumulates in macrophages of the lamina propia showed autofluorescence, sudanophilia, acid-fastness, and positiveness to PAS and Schmorl's reactions, all of which are common to lipofuscin and ceroids, plus an intense argentaffin reaction abolished by bleaching, indicative of a melanic substance. Lectin histochemistry showed, in decreasing order of frequency, the presence of alpha-D-mannose, sialic acid, beta-D-galactose (lactose), gal-beta-(1-3)acetyl-galactosamine, alpha-D-galactose, and alpha-L-fucose, but no terminal alpha-D-acetyl-galactosaminyl residues. CONCLUSIONS: The significant increase of apoptotic bodies in the lining colonic epithelium indicated that this type of cell death is not due to the natural programmed cell renewal, but to the action of laxatives. Because the autofluorescent pigment of melanosis coli contains melanin (as well as glycoconjugates) and is not dependent on age but on the use of anthranoid laxatives, it should be categorized as a "melanized ceroid." The lectin affinities of this pigment indicated that it contains a substantial number of saccharide residues almost similar to those found in the ceroid pigment of human aortic atheromas. These findings and considerations on the metabolism and pharmacokinetics of anthranoids suggested that the apoptotic epithelial cells, rather than the laxatives, may be the source of the pigment saccharides, whereas the precursors of the melanic substance may be derived from the anthranoids.


Subject(s)
Anthraquinones/adverse effects , Cathartics/adverse effects , Colon/drug effects , Colonic Diseases/chemically induced , Colonic Diseases/metabolism , Melanosis/chemically induced , Melanosis/metabolism , Pigments, Biological/chemistry , Adult , Aged , Aged, 80 and over , Apoptosis , Biopsy , Case-Control Studies , Ceroid/analysis , Colon/pathology , Colonic Diseases/pathology , Female , Humans , Immunohistochemistry , Intestinal Mucosa/drug effects , Intestinal Mucosa/pathology , Lectins , Male , Melanins/analysis , Melanosis/pathology , Microscopy, Fluorescence , Middle Aged , Senna Extract/adverse effects
8.
Biochim Biophys Acta ; 1360(3): 222-8, 1997 May 24.
Article in English | MEDLINE | ID: mdl-9197464

ABSTRACT

Fenofibrate, the hypolipidemic drug and peroxisome proliferator, was given to mice (0.23% w/w in the diet) during 1-3 weeks and H2O2 and TBARS steady state concentrations, liver chemiluminescence and antioxidant levels were measured. Administration of fenofibrate during 2 weeks induced an increase of 89% in H2O2 steady state concentration. Spontaneous chemiluminescence was decreased by 57% during fenofibrate treatment, while no significant effect was observed on TBARS concentration. Hydroperoxide-initiated chemiluminescence was decreased by 56% after 15 days of fenofibrate treatment, probably due to an increase in endogenous antioxidant levels. Total and oxidized glutathione increased gradually after fenofibrate administration, obtaining maximal increases of 67% and 58% respectively, after 22 days of treatment. An increase of 55% was found in ubiquinol levels in treated mice, as compared with the controls. alpha-tocopherol content was decreased by 51% in the liver of fenofibrate-treated mice. According to our findings, the high rate of H2O2 production associated with peroxisome proliferation, would not lead to an increase in lipid peroxidation. This can be explained by the presence of high levels of ubiquinols, which act as an antioxidant. The increased production of H2O2, would lead to DNA damage directly, and not through lipid peroxidation processes.


Subject(s)
Antioxidants/analysis , Fenofibrate/administration & dosage , Hypolipidemic Agents/administration & dosage , Liver/drug effects , Microbodies/drug effects , Animals , DNA Damage , Female , Glutathione/analysis , Hydrogen Peroxide/analysis , Lipid Peroxidation , Liver/metabolism , Liver/ultrastructure , Luminescent Measurements , Mice , Microbodies/metabolism , Thiobarbituric Acid Reactive Substances/analysis
9.
Medicina (B Aires) ; 57(2): 213-5, 1997.
Article in Spanish | MEDLINE | ID: mdl-9532833

ABSTRACT

Fibrillar collagen in the glomeruli is considered specific of the nail-patella syndrome. A new nephropathy with diffuse intraglomerular deposition of type III collagen without nail and skeletal abnormalities has been described. We report the case of a 26-year-old woman who presented persistent proteinuria, hematuria, deafness without nail and skeletal abnormalities. The renal biopsy showed focal and segmental glomerulosclerosis by light microscopy. The electron microscopy revealed the presence of massive fibrillar collagen within the mesangial matriz and the basement membrane. This is the first patient reported in our country. We emphasize the usefulness of electron microscopy in the study of glomerular diseases.


Subject(s)
Collagen Diseases/pathology , Kidney Glomerulus/pathology , Nephritis/pathology , Adult , Female , Humans , Microscopy, Electron
10.
Ren Fail ; 17(5): 525-37, 1995 Sep.
Article in English | MEDLINE | ID: mdl-8570865

ABSTRACT

Weanling rats fed a methyl-deficient diet develop renal necrosis with acute renal failure. The aim of this experiment was to explore further the role of coconut oil in this experimental model. Weanling Wistar male rats were fed methyl-deficient and their controls were fed methyl-supplemented diets. Coconut oil was fed at 14% and 20%, the latter concentration with and without 1% safflower oil (rich in linoleic acid); other groups received similar diets but instead of coconut oil, a mixture of hydrogenated vegetable oil and corn oil (rich in unsaturated fatty acids) was employed. Coconut oil fed at a 14% concentration did not evidence any protective outcome in relation to the renal lesions. Coconut oil at a 20% concentration showed a protective effect, mainly when the diet included safflower oil. The renal protective effect was evidenced by less or no mortality and increased survival time in the methyl-deficient rats receiving coconut oil, as well as by a reduced incidence (%) and severity of the renal lesions as evaluated by renal weight, and type (tubular and cortical necrosis or repair) and extent (grade) of the renal damage. The lack of a protective outcome when coconut oil was fed at 14%, along with the fact that in those rats receiving coconut oil at 20% the protection was greater when the diet was supplemented with 1% safflower oil, indicates that the protective effect should be attributed to the type of fatty acids coconut oil has and not to their shortage of essential fatty acids.


Subject(s)
Choline Deficiency/complications , Diet , Kidney Cortex Necrosis/prevention & control , Plant Oils/therapeutic use , Animals , Choline Deficiency/pathology , Coconut Oil , Kidney Cortex Necrosis/etiology , Kidney Cortex Necrosis/pathology , Male , Organ Size , Rats , Rats, Wistar
11.
Neurosci Lett ; 197(1): 29-32, 1995 Sep 01.
Article in English | MEDLINE | ID: mdl-8545048

ABSTRACT

The effects of atrial natriuretic factor (ANF) on norepinephrine (NE) uptake in circumventricular organs (organum vasculosum lamina terminalis, organum subfornicale and area postrema), locus coeruleus and nucleus tractus solitarii were studied in the rat. Experiments were carried out in vitro using nuclei obtained according to the punch-out technique. Results showed that 100 nM ANF enhanced NE uptake in all nuclei studied. These results suggest that ANF may be indirectly related to the control of cardiocirculatory functions, hydroelectrolyte balance, neuroendocrine secretions, nutrient and metabolic homeostasis, through the modulation of noradrenergic neurotransmission at the neuronal presynaptic level.


Subject(s)
Atrial Natriuretic Factor/pharmacology , Brain Chemistry/drug effects , Norepinephrine/metabolism , Animals , Hypothalamus/drug effects , Hypothalamus/metabolism , Locus Coeruleus/drug effects , Locus Coeruleus/metabolism , Male , Rats , Rats, Wistar , Sodium-Potassium-Exchanging ATPase/antagonists & inhibitors , Solitary Nucleus/drug effects , Solitary Nucleus/metabolism , Subfornical Organ/drug effects , Subfornical Organ/metabolism
12.
Histochem Cell Biol ; 103(6): 435-45, 1995 Jun.
Article in English | MEDLINE | ID: mdl-7584550

ABSTRACT

Little is known at present about the saccharide components of lipofuscin (age pigment) and ceroid pigments in situ. The purpose of this study was, therefore, to study in detail the lectin reactivities of lipofuscin in neurons and cardiac myocytes of old humans and rats. In addition, those of diverse ceroid pigments found in human aortic atheromas, in the livers of choline-deficient rats, in the uteri of vitamin E-deficient rats and in the crushed epididymal fat pad of rats, are included. Cryostat and deparaffinized sections from all these tissues were either extracted with a solvent mixture of chloroform-methanol-water (10:10:3, v/v) and incubated with 7 different biotinylated lectins or left untreated. Delipidation was done in order to study whether it was possible to discriminate between the saccharide moieties of glycolipids and glycoproteins of lipofuscin and ceroid pigments in situ. Other similarly treated sections were used to study the autofluorescence, sudanophilia, acid-fastness and reactivity to PAS. The frequency and intensity of lectin binding and standard histochemical properties of all the pigments were evaluated semi-quantitatively and blind. The results indicated that mannose was in general the most consistently detected sugar residue in lipofuscin granules of humans and rats, and that this pigment may also contain acetylglucosamine, acetylgalactosamine, sialic acid, galactose and fucose. However, notable differences were found not only in the lipofuscin saccharide components of different cell types of humans and rats, but also in those in the same type of cells in both species. Although mannose was not detected in the hepatic ceroid of choline-deficient rats, this saccharide moiety was almost always present in the other ceroid pigments. Each of the ceroids also contained other types of saccharides although the frequency of the latter varied between different ceroid pigments. While lipofuscin and each of the ceroid pigments showed somewhat different lectin binding patterns, the variability in the frequency of reactivity to lectins suggests that these patterns may not be permanent but transient. In this sense, it appears that lectin histochemistry may not allow these pigments to be differentiated. Furthermore, the extractive procedures used in this study did not enable us to determine whether the saccharides detected in the pigments in situ corresponded to glycolipids or glycoproteins.


Subject(s)
Ceroid/analysis , Lectins , Lipofuscin/analysis , Aged , Aged, 80 and over , Aging/metabolism , Animals , Brain Chemistry , Female , Fluorescence , Histocytochemistry , Humans , Male , Myocardium/chemistry , Myocardium/cytology , Neurons/chemistry , Rats , Rats, Wistar , Staining and Labeling/methods
13.
Gerontology ; 41 Suppl 2: 81-93, 1995.
Article in English | MEDLINE | ID: mdl-8821323

ABSTRACT

While results with inhibitors of thiol proteases have led to the suggestion that the progressive increase with age of lipofuscin in post-mitotic and some stable cells may be due to an age-related decline in the activity of these enzymes (Ivy et al., 1989), no direct evidence has been yet presented to support this hypothesis. In this study Wistar female rats were killed at age of 5, 14, and 24 months and the amounts of lipofuscin were histologically quantitated in neurons of the left cerebral parietal cortex and in cardiac myocytes of left ventricle. The sites of cathepsin B activity histochemically detected were quantitated in sections from left cerebral parietal cortex and left ventricle, and the activity of this enzyme was also measured biochemically in brain and heart homogenates. In line with previous findings, the amounts of lipofuscin in neurons and cardiac myocytes increased linearly during development and aging (from 5 to 14 and from 14 to 24 mo.). The sites of cathepsin B activity histochemically detected in sections from cerebral cortex significantly increased from 5 to 14 mo., but remained unchanged from 14 to 24 mo, while in sections from the left cardiac ventricle these sites of activity remained unchanged during development, and significantly increased during aging. On the other hand the biochemically determined activities of cathepsin B in brain and heart homogenates remained unchanged from 5 to 14 mo., but significantly decreased from 14 to 24 mo. These results suggest that the increase in lipofuscin with age may not be due to an age-wise decline in cathepsin B activity.


Subject(s)
Aging/physiology , Brain/metabolism , Cathepsins/metabolism , Lipofuscin/metabolism , Myocardium/metabolism , Animals , Brain/enzymology , Culture Techniques , Female , Immunohistochemistry , Lipofuscin/analysis , Myocardium/enzymology , Rats , Rats, Wistar
14.
Adv Exp Med Biol ; 266: 169-88; discussion 189-90, 1989.
Article in English | MEDLINE | ID: mdl-2486149

ABSTRACT

Previous studies in young normal rats have shown that intracerebral administration of the proteinase inhibitor, leupeptin, caused a rapid accumulation of lipofuscin-like pigment in lysosomes of brain cells (Ivy et al., 1984a). On the other hand, we have recently found that the administration of lovastatin, an inhibitor of HMG-CoA reductase, reduced the ceroid-like pigment and dolichol contents in the crushed epididymal fat pad of rats (Porta et al., 1988). In order to study now the possible modulating effects of these enzyme inhibitors on ceroidogenesis associated with vitamin E deficiency, two main groups of weanling Wistar female rats were respectively fed ad libitum a vitamin E-deficient basal diet, or the same diet supplemented with 16 mg% of dl-alpha-tocopherol acetate. The vitamin E-deficient and -supplemented rats were further subdivided and received for 8 weeks their diets alone or with 2, 1, or 0.5 g of lovastatin/kg of diet. Other subgroups were treated with constant peritoneal infusion of 0.5 mg/day of leupeptin by means of osmotic minipumps (Alzet 2002) consecutively implanted at days 15, 30, and 45. Lovastatin treatment to vitamin E-deficient rats was associated with dose-dependent toxicity, resulting in 100%, 75%, and 50% mortality at concentrations of 2, 1, and 0.5 g/kg diet, respectively. This mortality was mainly due to extensive hepatic necrosis. Food intake and growth rates were reduced, while the relative weights of liver, kidneys, spleen, heart and brain, as well as the serum levels of GPT and GOT were significantly increased over the values of the untreated vitamin E-deficient control rats. The volumetric densities of ceroid pigment and the dolichol contents in liver and kidneys were not significantly modified. Lovastatin toxicity was partially prevented by vitamin E supplementation. However, in these supplemented rats, lovastatin treatment did not modify the volumetric densities of hepatic and renal ceroid, although the contents of hepatic and renal dolichol were significantly increased. No correlations could be found between levels of hepatic or renal ceroid and total dolichol content in vitamin E-deficient and supplemented rats. Leupeptin treatment to vitamin E-deficient rats only slightly reduced food intake and growth rates, and did not significantly modify the relative organ weights or the serum levels of cholesterol, GOT and GPT. Although in both vitamin E-deficient and -supplemented rats the leupeptin treatment consistently showed a tendency to increase the volumetric densities of hepatic and renal ceroid pigment, the differences with the control untreated rats were not statistically significant.(ABSTRACT TRUNCATED AT 400 WORDS)


Subject(s)
Ceroid/biosynthesis , Leupeptins/pharmacology , Lovastatin/pharmacology , Vitamin E Deficiency/metabolism , Vitamin E/pharmacology , Alanine Transaminase/blood , Animals , Aspartate Aminotransferases/blood , Body Weight/drug effects , Cholesterol/blood , Dolichols/metabolism , Eating/drug effects , Female , Kidney/metabolism , Liver/metabolism , Organ Size/drug effects , Rats , Rats, Inbred Strains , Vitamin E Deficiency/drug therapy
15.
Br J Exp Pathol ; 69(4): 449-56, 1988 Aug.
Article in English | MEDLINE | ID: mdl-3179196

ABSTRACT

Wistar male rats were fed from weaning a methyl-deficient diet (groups I and II) or a standard commercial diet (groups III and IV). At the day 3 the left ureter was tied and divided in animals of groups I and III, while those in groups II and IV were sham operated. Rats of all groups were killed on days 8 and 10 to evaluate the incidence and extent of tubular necrosis (day 8) and tubular and cortical necrosis (day 10). The results of this study show that unilateral ureteric obstruction diminishes the incidence, severity and extent of necrosis in the same kidney.


Subject(s)
Acute Kidney Injury/pathology , Kidney Cortex Necrosis/pathology , Kidney Tubular Necrosis, Acute/pathology , Ureteral Obstruction/pathology , Animals , Body Weight , Choline Deficiency/complications , Diet , Feeding Behavior , Folic Acid Deficiency/complications , Kidney/pathology , Kidney Cortex Necrosis/etiology , Kidney Tubular Necrosis, Acute/etiology , Male , Methionine/deficiency , Rats , Rats, Inbred Strains , Vitamin B 12 Deficiency/complications
16.
Toxicon ; 26(12): 1137-44, 1988.
Article in English | MEDLINE | ID: mdl-3238699

ABSTRACT

The effects on lethal potency and enzymatic activity were determined following alkylation, with p-bromophenacyl bromide, of the acidic toxic phospholipase A2 from Bothrops alternatus. The modified B. alternatus enzyme, which lost its enzymatic activity, retained considerable toxicity. Histopathologic studies on mice have demonstrated features similar to those of the native enzyme. However, the distribution of the damage was different and the survival time was longer. It is concluded that the enzyme activity is not important for the lethal action of the enzyme although it influences the distribution of the damage and survival time.


Subject(s)
Acetophenones/pharmacology , Phospholipases A/toxicity , Phospholipases/toxicity , Viper Venoms/toxicity , Animals , Liver/drug effects , Liver/pathology , Mice , Myocardium/pathology , Phospholipases A/antagonists & inhibitors , Phospholipases A2 , Pulmonary Alveoli/drug effects , Pulmonary Alveoli/pathology
19.
Toxicon ; 24(8): 807-17, 1986.
Article in English | MEDLINE | ID: mdl-3775796

ABSTRACT

Purified phospholipase A2 from Bothrops alternatus venom is one single protein species with a molecular weight of 15,000 and isoelectric point 5.08. When injected i.p. or i.v. at a dose of 0.7 microgram/g body weight it is lethal to mice, eliciting a typical syndrome of dyspnea, tachycardia, arrhythmia and irreversible shock. Post mortem and histopathologic studies have demonstrated that the lungs (massive pulmonary hemorrhage), heart (foci of myocardial and endocardial necrosis with interfibrillar hemorrhage), liver (congestion, hepatocytic microvacuolization with zones of massive necrosis) and kidneys (foci of tubular and glomerular necrosis) were severely injured. Except for the less extensive hemorrhages and the significantly longer survival time, the observed lesions are similar to those observed after the injection of lethal doses of whole venom. The lethal potency of the purified enzyme (LD50 i.p. 0.14 microgram/g body weight) is 46-fold greater than that of the whole venom (LD50 i.p. 6.4 micrograms/g body weight). The contribution of phospholipase A2 to the overall lethal effect of B. alternatus venom is suggested by the decreased lethal potency of a venom sample in which a significant amount of phospholipase A2 has been removed and the full restoration of the lethal potency upon supplementation of the depleted sample with purified enzyme. It is concluded that phospholipase A2 is a major component responsible for lethality of the whole B. alternatus venom, while the contribution of other venom components appears to be significant mainly in reducing the time of survival.


Subject(s)
Crotalid Venoms/toxicity , Phospholipases A/toxicity , Phospholipases/toxicity , Animals , Crotalid Venoms/analysis , Kidney/drug effects , Kidney/pathology , Liver/drug effects , Liver/pathology , Lung/drug effects , Lung/pathology , Male , Mice , Myocardium/pathology , Phospholipases A/isolation & purification , Phospholipases A2
20.
Medicina (B.Aires) ; 46(2): 157-62, 1986. ilus, tab
Article in English | LILACS | ID: lil-50026

ABSTRACT

De 14 pacientes embarazadas que desarrollaron síndrome nefrótico e hipertensión arterial en el tercer trimestre de la gestación, en 7 se hallaron en la histopatología renal lesiones de preenclampsia y de escrerosis glomerular focal y segmentaria y en las 7 restantes sólo de preeclampsia. El hallazgo de la lesión esclerosante podría indicar una nefropatía preexistente complicada con una preeclampsia, o bien representar una lesión adicional de la glomerulopatía preeclámptica. Para analizar estas posibilidades, las enfermas fueron divididas en grupo I, con aquéllas que asociaron lesiones glomerulares de preclampsia y esclerosis segmentaria, y en grupo II, con sólo lesiones de preenclampsia. Ambos grupos fueron comparados con respecto a las alteraciones del riñon encontradas con microscopía óptica y electrónica, edades de las enfermas, paridad, antecedentes de hipertensión arterial, duración del embarazo, semana de comienzo de las manifestaciones clínicas de preeclampsia, duración de la preeclampsia, nivel de la presión arterial sistólica y diastólica, tasa de filtración glomerular, días entre el parto y la biopsia renal, recidiva de la preeclampsia, secuelas clínicas postparto (proteinuria y/o hipertensión arterial) y la evolución clínica alejada del parto. La confrontación de los grupos con respecto a los cambios observados con microscopía de luz mostró semajanza entre ellos, con excepción de las lesiones vinculadas a la esclerosis glomerular focal y segmentaria; en la microscopía ...


Subject(s)
Adult , Humans , Female , Pregnancy , Glomerulosclerosis, Focal Segmental/complications , Nephrotic Syndrome/etiology , Pre-Eclampsia/complications , Glomerulosclerosis, Focal Segmental/etiology , Glomerulosclerosis, Focal Segmental/pathology , Kidney/pathology , Nephrotic Syndrome/pathology
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