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 tyroxyne 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.

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.

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.

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.

Basic neurobiological research has recently reconsidered the capability of the adult mammalian central nervous system (CNS) neurons to undergo adaptive functional and morphological modifications in response to external noxious perturbations (Tsukahara, 1981; Cotman and Nieto-Sampedro, 1984). This new interest mainly stems from lesion and transplantation experiments documenting an unprecedented inherent plasticity of the mature CNS neurons following brain damage. The lesioned axons are now known to possess the ability to regrow when growth-promoting signals and substrates are introduced into their environment (Richardson et al., 1980; Kromer et al., 1981). In addition, a growing number of studies have provided evidence for a naturally occurring sprouting ability of intact axons following partial deafferentation (Cotman and Nieto-Sampedro, 1984). Yet loss of neuronal connectivity and function are still today common consequences of brain damage in the adult. What is critically needed is the comprehension of the cellular and molecular mechanisms underlying mature CNS plasticity following injury and its relationship to repair. Hopefully, this will in the near future provide novel ways for ameliorating the outcome following brain injury.

The pioneering work of Levi Montalcini and Hamburger (1951) has firmly established the concept that during neuronal ontogeny of the peripheral nervous system (PNS), neuronal survival and neurite outgrowth are regulated by a specific extrinsically occurring neuronotrophic agent termed nerve growth factor (NGF). More recently, it has been proposed that also in the central nervous system (CNS) neuronal survival and neurite number are controlled by extrinsically-occurring neuronotrophic factors (NTF). These agents presumably extend their regulatory activity throughout the whole life span (Varon and Adler 1980; Varon et al. 1983/84) and play an essential role in the restoration of neuronal activity following damage of the adult CNS (Gage et al. 1984).

International Journal of Developmental NeuroscienceVolume 3, Issue 4 p. 474-474 Aminergic System Effect of gm1, ganglioside on the expression of dopaminergic characteristics of embryonic mesencephalic cells in culture R. Dal Toso, R. Dal Toso Fidia Research Laboratories, Department of Biochemistry, Via Ponte delia Fabbrica 3/A, 35031 Abano Terme, ItalySearch for more papers by this authorA. Leon, A. Leon Fidia Research Laboratories, Department of Biochemistry, Via Ponte delia Fabbrica 3/A, 35031 Abano Terme, ItalySearch for more papers by this authorL. Facci, L. Facci Fidia Research Laboratories, Department of Biochemistry, Via Ponte delia Fabbrica 3/A, 35031 Abano Terme, ItalySearch for more papers by this authorD. Benvegnù, D. Benvegnù Fidia Research Laboratories, Department of Biochemistry, Via Ponte delia Fabbrica 3/A, 35031 Abano Terme, ItalySearch for more papers by this authorD. Prestl, D. Prestl Fidia Research Laboratories, Department of Biochemistry, Via Ponte delia Fabbrica 3/A, 35031 Abano Terme, ItalySearch for more papers by this authorA. Consolazione, A. Consolazione Fidia Research Laboratories, Department of Biochemistry, Via Ponte delia Fabbrica 3/A, 35031 Abano Terme, ItalySearch for more papers by this authorG. Toffano, G. Toffano Fidia Research Laboratories, Department of Biochemistry, Via Ponte delia Fabbrica 3/A, 35031 Abano Terme, ItalySearch for more papers by this author R. Dal Toso, R. Dal Toso Fidia Research Laboratories, Department of Biochemistry, Via Ponte delia Fabbrica 3/A, 35031 Abano Terme, ItalySearch for more papers by this authorA. Leon, A. Leon Fidia Research Laboratories, Department of Biochemistry, Via Ponte delia Fabbrica 3/A, 35031 Abano Terme, ItalySearch for more papers by this authorL. Facci, L. Facci Fidia Research Laboratories, Department of Biochemistry, Via Ponte delia Fabbrica 3/A, 35031 Abano Terme, ItalySearch for more papers by this authorD. Benvegnù, D. Benvegnù Fidia Research Laboratories, Department of Biochemistry, Via Ponte delia Fabbrica 3/A, 35031 Abano Terme, ItalySearch for more papers by this authorD. Prestl, D. Prestl Fidia Research Laboratories, Department of Biochemistry, Via Ponte delia Fabbrica 3/A, 35031 Abano Terme, ItalySearch for more papers by this authorA. Consolazione, A. Consolazione Fidia Research Laboratories, Department of Biochemistry, Via Ponte delia Fabbrica 3/A, 35031 Abano Terme, ItalySearch for more papers by this authorG. Toffano, G. Toffano Fidia Research Laboratories, Department of Biochemistry, Via Ponte delia Fabbrica 3/A, 35031 Abano Terme, ItalySearch for more papers by this author First published: 1985 https://doi.org/10.1016/0736-5748(85)90234-5AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume3, Issue41985Pages 474-474 RelatedInformation

The experimental strategy of adding monosialoganglioside GM 1 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 GM 1 in modulation of neuronal cell responsiveness to nerve growth factor (NGF). Data indicate that the addition of GM 1 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 GM 1 molecule apparently facilitates the acquisition or maintenance of the NGF‐induced specific neuronal properties. Results are consistent with the hypothesis that the presence of GM 1 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 GM 1 effects on the facilitation of central nervous system repair processes.

The role of gangliosides in neuronal differentiation was studied by addition of a mixture of bovine brain gangliosides to cultured neuroblastoma N2A cells. In ganglioside-treated cells the rate and degree of neurite formation was enhanced. Biochemical correlates indicate that the ganglioside-induced morphological differentiation is accompanied by a significant elongation of G1phase, a decrease in the rate of 3H-thymidine incorporation into cellular DNA and an increase of intracellular cAMP content.

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.

Intravenous injection of a sonicated dispersion of bovine brain phospholipids results in a significant change in both NaF‐dependent and dopamine dependent adenylate cyclase activity. High dosage of phospholipids inhibits the dopamine dependent, but not the NaF dependent, adenylate cyclase activity. The stimulation of cyclase activity is accompanied by an increased level of cAMP in mice brains. Treatment with haloperidol abolishes the increase in cAMP. Among individual phospholipids, phosphatidylserine is the most active component for inducing the activation of DA‐dependent adenylate cyclase activity.

Mice on an atherogenic diet for 40 days show a decrease in brain content of catecholamines, cyclic AMP and in dopamine degradation, and modification of the glycolytic pathway. The metabolic changes are paralleled by changes in behaviour, i.e. decrease in spontaneous motor activity and in conditioning avoidance response. The decrease in dopamine degradation and in behaviour parameters is partly due to the propylthiouracil present in the diet. Endovenous treatment with sonicated dispersions of bovine brain phospholipids induces a modification in the parameters of behaviour and metabolism. The possibility is discussed that some of the defects arising during the atherogenic diet are related with the establishment of a hypoxic state.

Endovenously administered sonicated liposomes of cerebral phospholipids (BC-PL) produce a rapid decrease of catecholamines, nor-epinephrine (NE) and dopamine (DA) in mouse brain. The parallel increase of homovanillic-acid (HVA) results in a shift in DA/HVA ratio, which is an indication of an increased cerebral catecholamine turnover. Phosphatidylserine (PS) is the most active component of BC-PL mixture.

1) Cholesterol - enriched diet induces changes in the phospholipid fatty acids of particulate fractions and modifications in the membrane-bound enzyme: 2) BC-PL (100 mg/kg i.p., as shown in rabbits) prevent cholesterol-induced modifications at brain level: 3)BC-PL (100 mg/kg i.v., as shown in mice) have a recovery effect on the cholesterol-induced modification at brain level; 4) It is suggested that some atherosclerotic lesions are analogous to those reproduced by anoxia; 5) It is suggested that the effect of BC-PL is a direct action at the level of the brain cellular membranes.