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1.
Climacteric ; 23(5): 474-481, 2020 10.
Article in English | MEDLINE | ID: mdl-32180466

ABSTRACT

Objective: This study evaluated the associations between food intake - especially omega-3 (n-3) - and depressive symptoms in climacteric women.Methods: Four hundred climacteric women were included in this research. The Kupperman Index, the Center for Epidemiologic Studies Depression Scale, and a 3-day food diary were used to investigate climacteric symptoms, depressive symptoms, and food intake, respectively. Sociodemographic, clinical, and anthropometric variables were also explored.Results: Statistically significant associations were observed between depression and climacteric symptoms, climacteric phase, previous history of depression, antidepressant drug use, family income, sleep pattern, and consumption of carbohydrates, fiber, polyunsaturated fatty acids, magnesium, zinc, and vitamins C, D, and B12. No association was observed between n-3 consumption and depression.Conclusion: Climacteric symptoms and food intake are important factors linked to depression during the climacteric period. Further studies are needed to clarify the changes in this phase of women's lives, as well as to investigate the role of the diet in the depression treatment or prevention.


Subject(s)
Depression/etiology , Diet/psychology , Eating/psychology , Menopause/psychology , Adult , Aged , Cross-Sectional Studies , Diet/statistics & numerical data , Diet Records , Diet Surveys , Fatty Acids, Omega-3/analysis , Female , Humans , Middle Aged
2.
Article in English | MEDLINE | ID: mdl-23791617

ABSTRACT

The influence of dietary fatty acids (FA) on mania-like behavior and brain oxidative damage were evaluated in rats. First generation of rats born and maintained under supplementation with soybean-oil (SO), fish-oil (FO) or hydrogenated-vegetable-fat (HVF), which are rich in n-6, n-3 and trans (TFA) FA, respectively, until adulthood, were exposed to an amphetamine (AMPH)-induced mania animal model to behavioral and biochemical evaluations. While AMPH caused hyperlocomotion in HVF and, to a less extent, in SO- and FO-groups, a better memory performance was observed in FO group. Among vehicle-groups, HVF increased reactive species (RS) generation and protein-carbonyl (PC) levels in cortex; FO reduced RS generation in hippocampus and decreased PC levels in hippocampus and striatum. Among AMPH-treated animals, HVF exacerbated RS generation in all evaluated brain areas and increased PC levels in cortex and striatum; FO reduced RS generation in hippocampus and decreased PC levels in hippocampus and striatum. FO was related to higher percentage of polyunsaturated fatty acids (PUFA) and docosahexaenoic acid (DHA) in cortex and striatum, while HVF was associated to higher incorporation of TFA in cortex, hippocampus and striatum, besides increased n-6/n-3 FA ratio in striatum. While a continuous exposure to TFA may intensify oxidative events in brain, a prolonged FO consumption may prevent mania-like-behavior; enhance memory besides decreasing brain oxidative markers. A substantial inclusion of processed foods, instead of foods rich in omega-3, in the long term is able to influence the functionality of brain structures related to behavioral disturbances and weaker neuroprotection, whose impact should be considered by food safety authorities and psychiatry experts.


Subject(s)
Brain/drug effects , Dietary Fats/pharmacology , Exploratory Behavior/drug effects , Fatty Acids/metabolism , Motor Activity/drug effects , Nerve Tissue Proteins/metabolism , Recognition, Psychology/drug effects , Amphetamine , Animals , Bipolar Disorder/chemically induced , Bipolar Disorder/diet therapy , Bipolar Disorder/metabolism , Brain/metabolism , Brain/physiology , Cerebral Cortex/drug effects , Cerebral Cortex/metabolism , Corpus Striatum/drug effects , Corpus Striatum/metabolism , Dietary Fats/therapeutic use , Female , Hippocampus/drug effects , Hippocampus/metabolism , Male , Pregnancy , Rats , Reactive Oxygen Species/metabolism
3.
Lipids ; 48(10): 977-87, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23737082

ABSTRACT

We evaluated the influence of fish oil (FO, rich in n-3 FA), soybean oil (SO, rich in n-6 FA) and hydrogenated vegetable fat (HVF, rich in trans FA) on the oxidative status and viability of skin cells of mice exposed to ultraviolet radiation (UVR). Mice were supplemented with FO, SO or HVF for three months and exposed to UVR (2.72 mJ/cm(2)) for 2 days. One day after the last UVR session, the FO group showed higher levels of n-3 fatty acids (FA), while the HVF showed higher incorporation of trans FA (TFA) in dorsal skin. UVR increased lipid peroxidation and protein carbonyl levels of the HVF and to a lesser extent of the control and SO groups. Although all irradiated groups showed increased skin thickness, this increase was slighter in FO mice. UVR exposure reduced skin cell viability of the control, SO and HVF groups, while FO prevented this. Catalase activity was reduced independently of the supplementation and SOD level was increased in C and FO groups after UVR exposure; FO prevented the UVR-induced increase in glutathione levels, which was observed in skin of the control, SO and HVF mice. Our results showed the beneficial effects of FO supplementation, as well as the harmful effects of trans FA, whose intensity can increase vulnerability to skin diseases.


Subject(s)
Diet , Oxidative Stress/drug effects , Skin/drug effects , Trans Fatty Acids/pharmacology , Ultraviolet Rays , Analysis of Variance , Animals , Cell Survival/drug effects , Fish Oils/pharmacology , Male , Mice , Oxidative Stress/radiation effects , Skin/radiation effects , Soybean Oil/pharmacology
4.
Ecotoxicol Environ Saf ; 91: 103-9, 2013 May.
Article in English | MEDLINE | ID: mdl-23433555

ABSTRACT

The aim of this study was to compare the effects of manganese (Mn) on silver catfish exposed to different levels of dissolved oxygen. Silver catfish (Rhamdia quelen) were exposed to increasing concentrations of Mn (4.2, 8.4 or 16.2mgL(-1)) under either normoxia (100 percent saturation) or moderate hypoxia (51.87 percent saturation) for 15 days. Under normoxia, Mn exposure increased lipid peroxidation (LP) in brain and kidney; it increased gluthatione (GSH) levels in brain and decreased catalase (CAT) activity in both tissues. Moderate hypoxia was able to prevent Mn-induced LP in brain and to reduce this oxidative parameter in kidney; GSH level was increased in brain, while CAT activity was reduced in both tissues. Activity of isolated mitochondria of liver and gills was reduced by Mn exposure under both levels of dissolved oxygen, but this effect was more prominent in normoxia. As expected, liver, kidney and gills showed an increase of Mn accumulation according to waterborne levels, and these parameters presented positive relationship. The highest waterborne Mn (8.4 and 16.2mgL(-1)) resulted in greater accumulation under normoxia, indicating that moderate hypoxia can stimulate mechanisms capable of reducing Mn accumulation in tissues (though not in blood). Moderate hypoxia can be considered a stress factor and Mn an aquatic anthropogenic contaminant. Therefore we hypothesized that these two conditions together are able to invoke defense mechanisms in juvenile silver catfish, acting in a compensatory form, which may be related to adaptation and/or hormesis.


Subject(s)
Catfishes/physiology , Lipid Peroxidation/drug effects , Manganese/toxicity , Oxygen/pharmacology , Water Pollutants, Chemical/toxicity , Animals , Body Weight/drug effects , Brain/drug effects , Catfishes/metabolism , Gills/drug effects , Gills/metabolism , Kidney/drug effects , Liver/drug effects , Manganese/analysis , Manganese/metabolism , Mitochondria/drug effects , Water Pollutants, Chemical/analysis
5.
Behav Brain Res ; 226(2): 504-10, 2012 Jan 15.
Article in English | MEDLINE | ID: mdl-22004982

ABSTRACT

The influence of trans fatty acids (FA) on development of orofacial dyskinesia (OD) and locomotor activity was evaluated. Rats were fed with diets enriched with 20% soybean oil (SO; n-6 FA), lard (L; saturated FA) or hydrogenated vegetable fat (HVF; trans FA) for 60 weeks. In the last 12 weeks each group was subdivided into sedentary and exercised (swimming). Brains of HVF and L-fed rats incorporated 0.33% and 0.20% of trans FA, respectively, while SO-fed group showed no incorporation of trans FA. HVF increased OD, while exercise exacerbated this in L and HVF-fed rats. HVF and L reduced locomotor activity, and exercise did not modify. Striatal catalase activity was reduced by L and HVF, but exercise increased its activity in the HVF-fed group. Na(+)K(+)-ATPase activity was not modified by dietary FA, however it was increased by exercise in striatum of SO and L-fed rats. We hypothesized that movement disorders elicited by HVF and less by L could be related to increased dopamine levels in striatum, which have been related to chronic trans FA intake. Exercise increased OD possibly by increase of brain dopamine levels, which generates pro-oxidant metabolites. Thus, a long-term intake of trans FA caused a small but significant brain incorporation of trans FA, which favored development of movement disorders. Exercise worsened behavioral outcomes of HVF and L-fed rats and increased Na(+)K(+)-ATPase activity of L and SO-fed rats, indicating its benefits. HVF blunted beneficial effects of exercise, indicating a critical role of trans FA in brain neurochemistry.


Subject(s)
Catalase/metabolism , Corpus Striatum/enzymology , Dietary Fats/adverse effects , Dyskinesia, Drug-Induced/metabolism , Physical Conditioning, Animal/physiology , Sodium-Potassium-Exchanging ATPase/metabolism , Trans Fatty Acids/adverse effects , Animals , Male , Motor Activity/drug effects , Physical Conditioning, Animal/methods , Rats , Rats, Wistar , Trans Fatty Acids/metabolism
6.
Drug Dev Ind Pharm ; 38(7): 792-9, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22066462

ABSTRACT

OBJECTIVE: Development of a hydrogel containing rutin at 0.025% (w/w) and evaluation of its in vivo efficacy in cutaneous wound healing in rats. METHODS: Hydrogels were prepared using Carbopol Ultrez® 10 NF and an aqueous dispersion of rutin in polysorbate 80. Hydrogels were characterized by means of pH measurement, rheological and spreadability analysis and rutin content determination by liquid chromatography. The in vivo healing effect was evaluated through the regression of skin lesions in rats and by analysis of oxidative stress. RESULTS AND DISCUSSION: Hydrogels showed adequate pH values (5.50-6.50) and pseudoplastic non-Newtonian behavior. After 5 days of treatment of wounds, hydrogels containing rutin presented a higher decrease in the wound area compared to the control hydrogels. Analysis of the oxidative stress showed a decrease in lipid peroxidation and protein carbonyl content as well as an increase in catalase activity after the treatment with the hydrogel containing rutin. Furthermore, this treatment increased total protein levels. CONCLUSION: This study shows for the first time the feasibility of using dermatological formulations containing rutin to improve skin wound healing.


Subject(s)
Acrylic Resins/chemistry , Polysorbates/chemistry , Rutin/administration & dosage , Wound Healing/drug effects , Administration, Cutaneous , Animals , Chemistry, Pharmaceutical/methods , Chromatography, Liquid/methods , Disease Models, Animal , Feasibility Studies , Hydrogels , Hydrogen-Ion Concentration , Lipid Peroxidation/drug effects , Male , Oxidative Stress/drug effects , Protein Carbonylation/drug effects , Rats , Rats, Wistar , Rheology , Rutin/pharmacology
7.
Neuroscience ; 195: 80-8, 2011 Nov 10.
Article in English | MEDLINE | ID: mdl-21893165

ABSTRACT

Here we evaluated the influence of physical exercise on behavior parameters and enzymatic status of rats supplemented with different dietary fatty acids (FA). Male Wistar rats fed diets enriched with soybean oil (SO), lard (L), or hydrogenated vegetable fat (HVF) for 48 weeks were submitted to swimming (30 min/d, five times per week) for 90 days. Dietary FA per se did not cause anxiety-like symptoms in the animals, but after physical exercise, SO group showed a better behavioral performance than L and the HVF groups in elevated plus maze (EPM). In Barnes maze, HVF group showed impaired memory acquisition as compared to L group, and exercise reversed this effect. SO-fed rats showed an improvement in memory acquisition after 1 day of training, whereas lard caused an improvement of memory only from day 4. HVF-fed rats showed no improvement of memory acquisition, but this effect was reversed by exercise in all training days. A lower activity of the Na(+)K(+)-ATPase in brain cortex of rats fed lard and HVF was observed, and this effect was maintained after exercise. Similarly, the HVF diet was related to lower activity of hippocampal Na(+)K(+)-ATPase, and exercise reduced activity of this enzyme in the SO and L groups. Our findings show influences of dietary FA on memory acquisition, whereas regular exercise improved this function and was beneficial on anxiety-like symptoms. As FA are present in neuronal membrane phospholipids and play a critical role in brain function, our results suggest that low incorporation of trans FA in neuronal membranes may act on cortical and hippocampal Na(+)K(+)-ATPase activity, but this change appears to be unrelated to the behavioral parameters primarily harmed by consumption of trans and less so by saturated FA, which were reversed by exercise.


Subject(s)
Brain/metabolism , Dietary Fats/adverse effects , Memory/physiology , Physical Conditioning, Animal/physiology , Animals , Anxiety/metabolism , Male , Maze Learning/physiology , Plant Oils/adverse effects , Rats , Rats, Wistar , Sodium-Potassium-Exchanging ATPase/metabolism , Soybean Oil/adverse effects
8.
Ecotoxicol Environ Saf ; 74(6): 1770-8, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21531023

ABSTRACT

The present study evaluated the role of pecan nut (Carya illinoensis) shells aqueous extract (AE) against oxidative damage induced by cigarette smoke exposure (CSE) and behavioral parameters of smoking withdrawal. Mice were passively exposed to cigarette smoke for 3 weeks (6, 10, and 14 cigarettes/day) and orally treated with AE (25 g/L). CSE induced lipid peroxidation in brain and red blood cells (RBC), increased catalase (CAT) activity in RBC, and decreased plasma ascorbic acid levels. AE prevented oxidative damage and increased antioxidant defenses of mice exposed to cigarette smoke. In addition, AE reduced the locomotor activity and anxiety symptoms induced by smoking withdrawal, and these behavioral parameters showed a positive correlation with RBC lipid peroxidation. Our results showed the beneficial effects of this by-product of the pecan industry, indicating its usefulness in smoking cessation.


Subject(s)
Antioxidants/pharmacology , Anxiety/chemically induced , Carya , Oxidative Stress/drug effects , Plant Extracts/pharmacology , Tobacco Smoke Pollution/adverse effects , Animals , Ascorbic Acid/blood , Catalase/metabolism , Lipid Peroxidation/drug effects , Male , Mice , Nuts
9.
J Environ Pathol Toxicol Oncol ; 29(3): 185-97, 2010.
Article in English | MEDLINE | ID: mdl-21303326

ABSTRACT

This study investigated the antioxidant effects of pecan nut (Carya illinoensis) shell aqueous extract (AE) on toxicity induced by cyclophosphamide (CP) in the heart, kidney, liver, bladder, plasma and erythrocytes of rats. Rats were treated with water or pecan shell AE (5%) ad libitum, replacing drinking water for 37 days up to the end of the experiment. On day 30, half of each group received a single administration of vehicle or CP 200 mg/kg-ip. After 7 days, the organs were removed. Rats treated with CP showed an increase in lipid peroxidation (LP) and decrease in reduced glutathione (GSH) levels in all structures. Catalase (CAT) activity was increased in the heart and decreased in liver and kidney. Besides, CP treatment decreased plasmatic vitamin C (VIT C) levels and induced bladder macroscopical and microscopical damages. In contrast, co-treatment with pecan shell AE prevented the LP development and the GSH depletion in all structures, except in the heart and plasma, respectively. CAT activity in the heart and liver as well as the plasmatic VIT C levels remained unchanged. Finally, AE prevented CP-induced bladder injury. These findings revealed the protective role of pecan shell AE in CP-induced multiple organ toxicity.


Subject(s)
Carya , Cyclophosphamide/toxicity , Plant Extracts/therapeutic use , Animals , Ascorbic Acid/blood , Catalase/metabolism , Glutathione/analysis , Lipid Peroxidation/drug effects , Male , Phytotherapy , Rats , Rats, Wistar
10.
Anal Chem ; 69(14): 2626-30, 1997 Jul 15.
Article in English | MEDLINE | ID: mdl-9341052

ABSTRACT

Microfabricated electrophoretic separation devices have been produced by an injection-molding process. The strategy for producing the devices involved solution-phase etching of a master template on a silicon wafer, followed by electroforming more durable injection-molding masters in nickel from the silicon master. One of the nickel electroforms was then used to prepare an injection mold insert, from which microchannel chips in an acrylic substrate were mass-produced. The microchannel devices were used to demonstrate high-resolution separations of double-stranded DNA fragments with total run times of less than 3 min. Run-to-run and chip-to-chip reproducibility was good, with relative standard deviation values below 1% for the run-to-run data and in the range of 2-3% for the chip-to-chip comparisons. Such devices could lead to the production of low-cost, single-use electrophoretic chips suitable for a variety of separation applications, including DNA sizing, DNA sequencing, random primary library screening, and rapid immunoassay testing.


Subject(s)
DNA/isolation & purification , Electrophoresis/instrumentation , Plastics , Bacteriophage phi X 174/genetics , DNA, Viral/isolation & purification , Electrophoresis/methods , Polymers , Reproducibility of Results
11.
Brain Res ; 633(1-2): 206-12, 1994 Jan 07.
Article in English | MEDLINE | ID: mdl-7907931

ABSTRACT

The presence of antibodies recognizing specific epitopes of dopaminergic neurons in serum of patients suffering of Parkinson's Disease (PD) as well as their capability to induce neuronal damage was investigated utilizing serum-free dissociated mesencephalic-striatal co-cultures. High affinity dopamine (DA) and GABA uptakes were assessed as specific, functional markers of dopaminergic and GABAergic cell viability, respectively. Heat-inactivated serum samples from 18 and 13 patients suffering from idiopathic and vascular parkinsonism, respectively and from 18 neurologic controls, were added to co-cultures on day 4 in vitro. Twenty four hours later, reconstituted rabbit complement was added for 60 min and uptake parameters as well as immunocytochemical staining for tyrosine hydroxylase (TH)-containing cells were subsequently assessed. DA, but not GABA, uptake was significantly decreased only when complement was added to cultures containing serum samples from 14 out of 18 patients with idiopathic parkinsonism and 3 out of 13 patients with vascular parkinsonism (Fisher test, P < 0.01). Complement addition to cultures containing serum samples from seropositive parkinsonian patients significantly reduced immunocytochemical staining of TH-containing cells. Seropositive and seronegative patients did not differ in demographic and clinical features. These results suggest that a complement-dependent humoral immune response occurs mainly in idiopathic parkinsonian patients, but its clinical relevance remains to be established.


Subject(s)
Antibodies/immunology , Complement System Proteins/physiology , Dopamine/physiology , Mesencephalon/cytology , Neurons/immunology , Parkinson Disease/blood , Aged , Animals , Antibodies, Monoclonal/immunology , Antibody-Dependent Cell Cytotoxicity , Cells, Cultured , Female , Humans , Immunohistochemistry , Male , Middle Aged , Neostriatum/cytology , Neurons/enzymology , Parkinson Disease/immunology , Rats , Tyrosine 3-Monooxygenase/immunology , Tyrosine 3-Monooxygenase/metabolism , gamma-Aminobutyric Acid/metabolism , gamma-Aminobutyric Acid/physiology
12.
Biochemistry ; 32(46): 12311-8, 1993 Nov 23.
Article in English | MEDLINE | ID: mdl-8241117

ABSTRACT

To examine the relationship between polypeptide chain synthesis and protein folding, we have constructed a circularly permuted variant of phage T4 lysozyme. The permuted protein begins at residue 37 of the wild-type sequence and ends at residue 36. The normal chain termini are joined by a six-residue linker, Ser-Gly4-Ala. The permuted lysozyme folds efficiently and cleaves bacterial cell walls with normal specific activity. As judged by circular dichroism, UV absorbance, fluorescence, and nuclear magnetic resonance spectroscopy, the permutation causes little change in the structure of the protein. Reversible denaturation experiments show that the permutation reduces the stability of T4 lysozyme only 0.8-1.1 kcal/mol. These results demonstrate that a protein with two domains can be permuted with little change in activity, structure, and stability. The order of chain synthesis, the sequential arrangement of secondary structures, and the position of chain termini with respect to domain boundaries do not determine the protein fold.


Subject(s)
Muramidase/chemistry , Amino Acid Sequence , Bacteriophage T4/enzymology , Base Sequence , Calorimetry, Differential Scanning , DNA, Recombinant , Genes, Viral , Magnetic Resonance Spectroscopy , Molecular Sequence Data , Motion , Oligodeoxyribonucleotides/chemistry , Protein Denaturation , Protein Structure, Tertiary , Restriction Mapping , Structure-Activity Relationship , Thermodynamics , Viral Structural Proteins/genetics
13.
Matrix Suppl ; 1: 112-5, 1992.
Article in English | MEDLINE | ID: mdl-1480011

ABSTRACT

The elastase protein of Pseudomonas aeruginosa is a zinc metalloprotease which has been shown to be a member of the bacterial neutral protease family. Its overall tertiary structure is similar to that of thermolysin. The x-ray crystallographic structure of the elastase has been solved to high resolution in three different crystal forms. Substantial conformational differences are observed in the protein in different crystal forms. In the absence of ligand, and independently in the presence of a covalent noncompetitive inhibitor, the elastase is observed to have a relatively "open" substrate binding cleft, while in the presence of tight-binding competitive inhibitors, the active site cleft is "closed".


Subject(s)
Bacterial Proteins/chemistry , Metalloendopeptidases/chemistry , Protein Structure, Tertiary , Pseudomonas aeruginosa/enzymology , Amino Acid Sequence , Bacterial Proteins/antagonists & inhibitors , Binding Sites , Metalloendopeptidases/antagonists & inhibitors , Models, Molecular , Molecular Sequence Data , Protein Conformation , X-Ray Diffraction , Zinc
14.
Proc Natl Acad Sci U S A ; 88(2): 561-4, 1991 Jan 15.
Article in English | MEDLINE | ID: mdl-1988953

ABSTRACT

Dimerization of the bZIP class of eukaryotic transcriptional control proteins requires a sequence motif called the leucine zipper. We have grown two distinct crystal forms of a 33-amino acid peptide corresponding to the leucine zipper of the yeast transcriptional activator GCN4. This peptide is known to form a dimer of parallel helices in solution. X-ray scattering from both crystal forms shows reflections that are diagnostic of coiled coils. The most notable reflections occur at approximately 5.2 A resolution and correspond to the pitch of helices in coiled coils. There is no diffraction maximum near 5.4 A, the characteristic pitch of straight helices. Our results provide direct evidence that the leucine zipper of GCN4 is a coiled coil.


Subject(s)
Leucine Zippers , Peptides/chemistry , Amino Acid Sequence , Crystallization , Molecular Sequence Data , Peptides/chemical synthesis , Protein Conformation , X-Ray Diffraction
15.
J Mol Recognit ; 3(5-6): 187-91, 1990.
Article in English | MEDLINE | ID: mdl-2096885

ABSTRACT

A functional role for Nerve Growth Factor (NGF) in the peripheral nervous system is well-documented, but a similar case for NGF in the central nervous system remains to be established. One approach to answering this question would be the availability of high-affinity monospecific Fab fragments obtained against NGF. In the present studies we describe the preparation and characterization of such Fab fragments from anti-mouse NGF polyclonal antibodies. Following their purification by the use of a NGF Sepharose-coupled affinity column, the Fab fragments were examined for biological competence in several ways. In vitro, the anti-Fab fragments blocked the neuronotrophic activity of NGF, as measured by the survival of chicken embryonic day 8 dorsal root ganglion neurons. In vivo, these Fab fragments, when administered systemically to neonatal rats, produced a decrease of noradrenaline levels in two sympathetically innervated organs, the heart and the spleen. These findings suggest that affinity purified Fab fragments of anti-NGF antibodies can be a useful tool for studying the physiological function of NGF in the nervous system.


Subject(s)
Immunoglobulin Fab Fragments/isolation & purification , Nerve Growth Factors/immunology , Animals , Chick Embryo , Female , Immunoblotting , Immunoglobulin Fab Fragments/administration & dosage , Immunoglobulin Fab Fragments/immunology , Male , Mice , Nerve Growth Factors/isolation & purification , Norepinephrine/metabolism , Rats , Rats, Inbred Strains
16.
J Neurosci ; 8(3): 733-45, 1988 Mar.
Article in English | MEDLINE | ID: mdl-3346717

ABSTRACT

The use of CNS cultures for detection and quantification of neuronotrophic activity in the CNS has been analyzed. In particular the development, i.e., neurotransmitter uptake characteristics, and survival of dopaminergic and GABAergic neurons in fetal mouse (E13)-dissociated mesencephalic cells cultured in serum-free, hormone-supplemented medium have been assessed as a function of culture time and cell density. At all times, more than 98% of the cells were classified as neurons on the basis of immunocytochemical criteria. Results indicate that the increase of cell density in vitro significantly enhances specific high-affinity dopamine uptake per dopaminergic cell and cell survival. This effect is not limited to the dopaminergic cells and suggests that the development of neurotransmitter-related traits and cell survival are influenced by cell density-derived trophic signals. The above-mentioned cultures and parameters have also been used to detect neuronotrophic activity in adult mammalian brain extracts or more purified preparations. In particular, bovine striatal extracts contain activity capable of increasing high-affinity neurotransmitter uptake parameters and cell survival of at least the dopaminergic and GABAergic neurons present in the culture system. The neuronotrophic activity from bovine striatum has been partially purified and is associated with a fraction whose main component is a basic protein of approximately 14 kDa.


Subject(s)
Mesencephalon/physiology , Neurons/physiology , Animals , Caudate Nucleus/analysis , Cell Survival/drug effects , Cells, Cultured , Dopamine/metabolism , Dopamine/pharmacokinetics , Embryo, Mammalian , Mesencephalon/cytology , Mesencephalon/metabolism , Mice , Nerve Growth Factors , Nerve Tissue Proteins/analysis , Nerve Tissue Proteins/isolation & purification , Nerve Tissue Proteins/pharmacology , Neurons/metabolism , gamma-Aminobutyric Acid/pharmacokinetics
17.
J Neurosci ; 8(3): 746-53, 1988 Mar.
Article in English | MEDLINE | ID: mdl-3346718

ABSTRACT

This paper analyzes the effects of exogenously supplied GM1 on the development, i.e., specific neurotransmitter uptake capability and survival, of the dopaminergic neurons present in fetal mouse-dissociated mesencephalic cells. Exogenous GM1, but not asialo-GM1, sialic acid, or the oligosaccharide chain of GM1, enhances in a time- and concentration-dependent manner the specific 3H-dopamine uptake (increase of the apparent Vmax and decrease of the apparent Km value) and the long-term survival of the dopaminergic neurons. The GM1 effects on the behavior of the dopaminergic neurons require the presence of cell-derived neuronotrophic influences present within the culture system and are associated with an increase in the response of the cells to the trophic influences. GM1 effects are not limited to dopaminergic neurons, and depend on the stable association of the ganglioside molecule with the cells. It is suggested that GM1 is not a trophic agent per se, but rather potentiates neuronotrophic activities and/or exerts independent influences to which neurons respond only if appropriately supported.


Subject(s)
Cell Survival/drug effects , Gangliosides/pharmacology , Mesencephalon/drug effects , Neurons/physiology , Animals , Cells, Cultured , Dopamine/metabolism , Embryo, Mammalian , In Vitro Techniques , Mesencephalon/metabolism , Mesencephalon/physiology , Mice , Neurons/drug effects , Neurons/metabolism , gamma-Aminobutyric Acid/metabolism
18.
J Neurosci Res ; 12(2-3): 277-87, 1984.
Article in English | MEDLINE | ID: mdl-6502753

ABSTRACT

The experimental strategy of adding monosialoganglioside GM1 to a culture medium of fetal chick dorsal root ganglia (DRG) was utilized as a model system in which to examine the potential role of GM1 in modulation of neuronal cell responsiveness to nerve growth factor (NGF). Data indicate that the addition of GM1 to DRG explants or to DRG dissociated neuronal cells in culture enhances NGF-induced neurite outgrowth, neurite complexity, and neuronal cell survival following NGF withdrawal. The GM1 molecule apparently facilitates the acquisition or maintenance of the NGF-induced specific neuronal properties. Results are consistent with the hypothesis that the presence of GM1 molecules on the neuronal cell surface, either endogenous or following stable insertion of exogenous molecules, plays a prominent role in the modulation of functional neuronal cell behavior in response to varying neuronotrophic signals. This may prove to be relevant for the comprehension of GM1 effects on the facilitation of central nervous system repair processes.


Subject(s)
G(M1) Ganglioside/pharmacology , Gangliosides/pharmacology , Models, Neurological , Nerve Growth Factors/pharmacology , Neurons/drug effects , Animals , Cell Differentiation/drug effects , Cell Survival/drug effects , Cells, Cultured , Chick Embryo , Culture Techniques , Ganglia, Spinal
20.
J Neurochem ; 35(4): 861-6, 1980 Oct.
Article in English | MEDLINE | ID: mdl-7452294

ABSTRACT

The binding of GM1 ganglioside to crude preparations of rat brain neuronal membranes was studied, the following results being obtained: (a) the binding process followed a biphasic kinetics, which displayed a break at 0.07-0.08 x 10(-6) M GM1 concentration; (b) the features of the binding process at GM1 concentrations below the break and, over the break, above 10(-6) M appeared to be different. Below the break the process proceeded slowly and brought a stable and irreversible association of GM1 molecules to the membranes. Over 10(-6) M the process was much more rapid and caused GM1 molecules to interact in such a way that they were releasable by washing and could exchange with newly added free ganglioside; (c) the two binding processes displayed the characteristics of a saturation phenomenon; (d) in both cases, GM1 taken up was freely available to galactose oxidase, indicating that the oligosaccharide chains protrude from the membrane surface. We postulate that GM1 occurs, below and above the break, in different physical forms, each of them having a different mechanism of interaction with the membrane. Above 10(-6) M GM1 interacts as micelles, and the basis of the micelle-membrane interaction is a fusion process. Below the break, in the 10(-8)--10(-7) M range, the binding is the result of hydrophobic interactions between sites on the membrane and the hydrophobic portion of individual ganglioside molecules, most likely in the monomeric form.


Subject(s)
Brain/metabolism , G(M1) Ganglioside/metabolism , Gangliosides/metabolism , Neurons/metabolism , Animals , Binding Sites , Cell Membrane/metabolism , Galactose Oxidase/metabolism , Kinetics , Male , Rats
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