Biomedical subjects

Marco Fiore

Publications and source records attributed to Marco Fiore.

23 records · Page 2Linked to original sources

PubMed2002

Brain NGF and EGF administration improves passive avoidance response and stimulates brain precursor cells in aged male mice.

Nerve growth factor (NGF) has been shown to improve damage in spatial cognition following aging, whereas epidermal growth factor (EGF) is important in brain cell proliferation. It is also known that the adult mammalian central nervous system contains persistent progenitor cells with characteristics of stem cells. These studies suggest that under appropriate external stimuli progenitor cells may generate neuronal and glial cells promoting recovery of the injured nervous system. However, little is known about the presence and responsiveness of progenitor cells in the aged brain. In the present investigation, we studied the effect of brain intracerebroventricular injections of EGF and/or NGF on progenitor cells of the subventricular area (SVZ) in aged male mice to test learning performances in the passive avoidance apparatus. We found that neither NGF nor EGF improved learning responses. However, combined NGF and EGF administration in the brain improved learning responses of aged mice in the passive avoidance when compared with aged matched nontreated controls. These findings resulted to be associated with increased immunopositivity to progenitor cells in the SVZ. The possible functional implications of these data are discussed.

Aging↗

PubMed2002

Healing action of nerve growth factor on lameness in adult goats.

We investigated the effect of nerve growth factor in goats affected by lameness, a condition that is associated with cutaneous ulcers, abscesses and granulomas. Lesions were treated daily with 1 microgram of nerve growth factor (NGF), dissolved in 100 microliters of sesame oil or with sesame oil only. Healthy controls were treated with sesame oil only for periods ranging from two to four weeks and behavioral, biochemical and histopathological conditions were evaluated. Topical application of NGF, but not sesame oil, promoted ulcer healing in all goats within two-three weeks of treatment. The effect of NGF was to re-establish in about 60 days normal locomotion and indirectly to improve feeding behavior and milk production. These findings suggest that NGF might be clinically useful for healing damaged skin in goats and confirm previous studies on human corneal ulcers.

Administration, Topical↗

PubMed2002

Short-term hypergravity influences NGF and BDNF expression, and mast cell distribution in the lungs and heart of adult male mice.

In this study we investigate the effects of short-term hypergravity on lung and heart neurotrophins and mast cell distribution. Our results showed that brain derived-neurotrophic factor (BDNF) protein and mRNA expression are increased in the lungs of mice exposed to hypergravity while in the heart hypergravity causes a marked reduction in BDNF mRNA expression, and a decrease in BDNF protein. Compared to controls, nerve growth factor (NGF) protein was expressed more in the heart of rotated mice. These observations demonstrate that altered hypergravity can affect, though differentially, the local expression of NGF and BDNF proteins and their mRNAs in the lung and heart and indicates that short-term exposure to hypergravity causes a marked increase in BDNF, but not in NGF in the lungs of adult mice. Moreover, mast cells, which are NGF-producing cells and implicated in cardiac and respiratory activity, increased in number in proximity to blood vessels in the heart and in lung airway epithelium of rotated mice. This study indicates that hypergravity influences cardiovascular and respiratory tissue and suggests a neurotrophin involvement in the reaction to this environmental exposure.

Animals↗

PubMed2000

Chronic antipsychotic treatment selectively alters nerve growth factor and neuropeptide Y immunoreactivity and the distribution of choline acetyl transferase in rat brain regions.

Neuropeptides and neurotrophins play a number of roles in the central nervous system (CNS). Nerve growth factor (NGF), the first characterized member of the family of neurotrophins, influences the synthesis of some neuropeptides, including neuropeptide Y (NPY), a peptide amply expressed in the CNS, interacting with catecholamines and modifying behaviour. In this study we investigated whether antipsychotic treatment affects the constitutive levels of NGF-, NPY- and choline acetyl transferase (ChAT)-like immunoreactivities (-LI) in the CNS. Rats were fed food supplemented with haloperidol (1.15 mg/100 g food), risperidone (1.15 or 2.3 mg/100 g food), or vehicle. After 29 d treatment animals were sacrificed with focused high-energy microwave irradiation for radioimmunoassay (RIA) of NPY-LI, by decapitation for analysis of NGF, and by perfusion for immunocytochemistry. Haloperidol and risperidone elevated NGF-LI concentrations in the hypothalamus but decreased NGF-LI in the striatum and hippocampus. In contrast, antipsychotics did not alter NPY-LI in the striatum. Haloperidol increased NPY-LI concentration in the occipital cortex, while risperidone increased NPY-LI in the occipital cortex, hippocampus, and hypothalamus. Significant decreases in ChAT immunoreactivity in large-size neurons following both haloperidol and risperidone treatments in the septum as well as Meynert's nucleus were observed. Our findings demonstrate that antipsychotic drugs alter the regional brain levels of NGF-LI, NPY-LI and ChAT-LI and raise the possibility that these effects are implicated in their pharmacological and therapeutic properties.

Journal Article↗

PubMedDate not supplied

Long-lasting effects of prenatal MAM treatment on water maze performance in rats: associations with altered brain development and neurotrophin levels.

We previously reported that prenatal methylazoxymethanol (MAM) administered on days 11 and 12 of rat pregnancy induces structural changes in the cytoarchitecture of the hippocampal-entorhinal axis. We also showed that young and middle-aged prenatally treated MAM animals displayed changes in brain neurotrophin levels [Neurosci. Lett. 309 (2001) 113; Physiol. Behav. 71 (2000) 57.]. To continue this line of investigation, the working hypothesis adopted was that prenatal MAM administration, by interfering with limbic neurogenesis, could impair learning and memory ability of aged animals in the water maze. It was found that injection of MAM during early rat brain development induced deficits in both the acquisition and retention phases of the Morris maze. These behavioral changes were associated with significant changes in brain nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), reduced choline acetyltransferase (ChAT) immunoreactivity in forebrain cholinergic neurons and loss of neuropeptide Y (NPY) immunodistribution in cells of the entorhinal cortex. This finding, as well as confirming previous studies showing that injection of prenatal MAM administration induces significant changes in hippocampal-entorhinal axis neurogenesis and marked behavioral deficits in adult life, provides additional experimental evidence supporting the hypothesis that loss of NGF and/or BDNF-receptive or producing cells can co-occur at the onset of neurodevelopmental disorders.

Animals↗