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Custer GF, Bresciani L, Dini-Andreote F. Toward an integrative framework for microbial community coalescence. Trends Microbiol 2024; 32:241-251. [PMID: 37778924 DOI: 10.1016/j.tim.2023.09.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 09/05/2023] [Accepted: 09/11/2023] [Indexed: 10/03/2023]
Abstract
Community coalescence is defined as the mixing of intact ecological communities. From river confluences to fecal microbiota transplantation, community coalescence constitutes a common ecological occurrence affecting natural and engineered microbial systems. In this opinion article, we propose an integrative framework for microbial community coalescence to guide advances in our understanding of this important - yet underexplored - ecological phenomenon. We start by aligning community coalescence with the unified framework of biological invasion and enumerate commonalities and idiosyncrasies between these two analogous processes. Then, we discuss how organismal interactions and cohesive establishment affect coalescence outcomes with direct implications for community functioning. Last, we propose the use of ecological null modeling to study the interplay of ecological processes structuring community reassembly following coalescence.
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Affiliation(s)
- Gordon F Custer
- Department of Plant Science and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA; The One Health Microbiome Center, Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA.
| | - Luana Bresciani
- Department of Plant Science and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA; The One Health Microbiome Center, Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA
| | - Francisco Dini-Andreote
- Department of Plant Science and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA; The One Health Microbiome Center, Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA.
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2
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Baron G, Altomare A, Della Vedova L, Gado F, Quagliano O, Casati S, Tosi N, Bresciani L, Del Rio D, Roda G, D'Amato A, Lammi C, Macorano A, Vittorio S, Vistoli G, Fumagalli L, Carini M, Leone A, Marino M, Del Bo' C, Miotto G, Ursini F, Morazzoni P, Aldini G. Unraveling the parahormetic mechanism underlying the health-protecting effects of grapeseed procyanidins. Redox Biol 2024; 69:102981. [PMID: 38104483 PMCID: PMC10770607 DOI: 10.1016/j.redox.2023.102981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 11/28/2023] [Accepted: 11/29/2023] [Indexed: 12/19/2023] Open
Abstract
Proanthocyanidins (PACs), the predominant constituents within Grape Seed Extract (GSE), are intricate compounds composed of interconnected flavan-3-ol units. Renowned for their health-affirming properties, PACs offer a shield against a spectrum of inflammation associated diseases, such as diabetes, obesity, degenerations and possibly cancer. While monomeric and dimeric PACs undergo some absorption within the gastrointestinal tract, their larger oligomeric and polymeric counterparts are not bioavailable. However, higher molecular weight PACs engage with the colonic microbiota, fostering the production of bioavailable metabolites that undergo metabolic processes, culminating in the emergence of bioactive agents capable of modulating physiological processes. Within this investigation, a GSE enriched with polymeric PACs was employed to explore in detail their impact. Through comprehensive analysis, the present study unequivocally verified the gastrointestinal-mediated transformation of medium to high molecular weight polymeric PACs, thereby establishing the bioaccessibility of a principal catabolite termed 5-(3',4'-dihydroxyphenyl)-γ-valerolactone (VL). Notably, our findings, encompassing cell biology, chemistry and proteomics, converge to the proposal of the notion of the capacity of VL to activate, upon oxidation to the corresponding quinone, the nuclear factor E2-related factor 2 (Nrf2) pathway-an intricate process that incites cellular defenses and mitigates stress-induced responses, such as a challenge brought by TNFα. This mechanistic paradigm seamlessly aligns with the concept of para-hormesis, ultimately orchestrating the resilience to stress and the preservation of cellular redox equilibrium and homeostasis as benchmarks of health.
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Affiliation(s)
- G Baron
- Department of Pharmaceutical Sciences (DISFARM), Università degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy
| | - A Altomare
- Department of Pharmaceutical Sciences (DISFARM), Università degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy
| | - L Della Vedova
- Department of Pharmaceutical Sciences (DISFARM), Università degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy
| | - F Gado
- Department of Pharmaceutical Sciences (DISFARM), Università degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy
| | - O Quagliano
- Department of Pharmaceutical Sciences (DISFARM), Università degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy
| | - S Casati
- Department of Biomedical, Surgical and Dental Sciences, Università degli Studi di Milano, Via Luigi Mangiagalli 37, 20133, Milan, Italy
| | - N Tosi
- Human Nutrition Unit, Department of Food & Drug, University of Parma, Via Volturno 39, 43125, Parma, Italy
| | - L Bresciani
- Human Nutrition Unit, Department of Food & Drug, University of Parma, Via Volturno 39, 43125, Parma, Italy
| | - D Del Rio
- Human Nutrition Unit, Department of Food & Drug, University of Parma, Via Volturno 39, 43125, Parma, Italy
| | - G Roda
- Department of Pharmaceutical Sciences (DISFARM), Università degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy
| | - A D'Amato
- Department of Pharmaceutical Sciences (DISFARM), Università degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy
| | - C Lammi
- Department of Pharmaceutical Sciences (DISFARM), Università degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy
| | - A Macorano
- Department of Pharmaceutical Sciences (DISFARM), Università degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy
| | - S Vittorio
- Department of Pharmaceutical Sciences (DISFARM), Università degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy
| | - G Vistoli
- Department of Pharmaceutical Sciences (DISFARM), Università degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy
| | - L Fumagalli
- Department of Pharmaceutical Sciences (DISFARM), Università degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy
| | - M Carini
- Department of Pharmaceutical Sciences (DISFARM), Università degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy
| | - A Leone
- International Center for the Assessment of Nutritional Status and the Development of Dietary Intervention Strategies (ICANS-DIS), Via Sandro Botticelli 21, 20133, Milan, Italy; Department of Food, Environmental and Nutritional Sciences (DeFENS), Division of Human Nutrition, Università degli Studi di Milano, Via Luigi Mangiagalli 25, 20133, Milan, Italy
| | - M Marino
- Department of Food, Environmental and Nutritional Sciences (DeFENS), Division of Human Nutrition, Università degli Studi di Milano, Via Luigi Mangiagalli 25, 20133, Milan, Italy
| | - C Del Bo'
- Department of Food, Environmental and Nutritional Sciences (DeFENS), Division of Human Nutrition, Università degli Studi di Milano, Via Luigi Mangiagalli 25, 20133, Milan, Italy
| | - G Miotto
- Department of Molecular Medicine, Viale G. Colombo, 3, University of Padova, 35121, Padova, Italy
| | - F Ursini
- Department of Molecular Medicine, Viale G. Colombo, 3, University of Padova, 35121, Padova, Italy
| | - P Morazzoni
- Divisione Nutraceutica, Distillerie Umberto Bonollo S.p.A, 35035, Mestrino, Italy
| | - G Aldini
- Department of Pharmaceutical Sciences (DISFARM), Università degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy.
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Abstract
Dispersal is simply defined as the movement of species across space and time. Despite this terse definition, dispersal is an essential process with direct ecological and evolutionary implications that modulate community assembly and turnover. Seminal ecological studies have shown that environmental context (e.g., local edaphic properties, resident community), dispersal timing and frequency, and species traits, collectively account for patterns of species distribution resulting in either their persistence or unsuccessful establishment within local communities. Despite the key importance of this process, relatively little is known about how dispersal operates in microbiomes across divergent systems and community types. Here, we discuss parallels of macro- and micro-organismal ecology with a focus on idiosyncrasies that may lead to novel mechanisms by which dispersal affects the structure and function of microbiomes. Within the context of ecological implications, we revise the importance of short- and long-distance microbial dispersal through active and passive mechanisms, species traits, and community coalescence, and how these align with recent advances in metacommunity theory. Conversely, we enumerate how microbial dispersal can affect diversification rates of species by promoting gene influxes within local communities and/or shifting genes and allele frequencies via migration or de novo changes (e.g., horizontal gene transfer). Finally, we synthesize how observed microbial assemblages are the dynamic outcome of both successful and unsuccessful dispersal events of taxa and discuss these concepts in line with the literature, thus enabling a richer appreciation of this process in microbiome research.
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Affiliation(s)
- Gordon F Custer
- Department of Plant Science and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, United States
| | - Luana Bresciani
- Department of Plant Science and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, United States
| | - Francisco Dini-Andreote
- Department of Plant Science and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, United States
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Capaccio P, Di Pasquale D, Bresciani L, Torretta S, Pignataro L. 3D video-assisted trans-oral removal of deep hilo-parenchymal sub-mandibular stones. ACTA ACUST UNITED AC 2019; 39:367-373. [PMID: 31388194 PMCID: PMC6966778 DOI: 10.14639/0392-100x-2282] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Accepted: 09/25/2018] [Indexed: 12/21/2022]
Abstract
The aim of this paper is to describe the intra-operative findings and surgical results of the first application of 3D high-definition (HD) endoscopic support to the trans-oral surgical treatment of five patients with deep hilo-parenchymal sub-mandibular stones who underwent clinical and ultrasonographic (US) follow-up examinations at one month after the procedure. Five patients undergoing 2D-HD video-assisted transoral surgery for the same condition were used as controls. The results were classified as successful (US - demonstrated complete clearance) or unsuccessful (US - demonstrated total or partial persistence). Visual analogue scales (VAS) were used post-surgically to evaluate the sharpness and brightness of the 2D and 3D images on the screen and stereoscopic depth perception (SDP) of the 3D-HD endoscope. Successful stone removal and significant subjective improvement (lack of obstructive symptoms) was obtained in all but one of the patients in the 3D group, in whom the one-month US evaluation revealed a residual 3 mm asymptomatic hilo-parenchymal stone that was successfully treated by sialendoscopy-assisted intra-corporeal laser lithotripsy. Wharton’s duct and the lingual nerve were identified and preserved in all cases. The mean 3D-HD VAS results were brightness 7 (range 6-8), sharpness 7.8 (range 7-9) and SDP 8.2 (range 8-9); the mean 2D-HD results were brightness 7.8 (range 7-9) and sharpness 7 (range 7-8). Our findings confirm the safety and efficacy of conservative transoral surgical treatment of hilo-parenchymal sub-mandibular stones. From a surgeon’s perspective, 3D-HD guided exploration of the oral floor seems to provide a better view of Wharton’s duct and the lingual nerve, especially near the sub-mandibular parenchyma. The 3D-HD video-assisted transoral removal of deep hilo-parenchymal sub-mandibular stones can therefore be considered a useful new means of preserving the function of an obstructed salivary gland.
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Affiliation(s)
- P Capaccio
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy.,Department of Biomedical, Surgical and Dental Sciences, Università degli Studi di Milano, Italy
| | - D Di Pasquale
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy
| | - L Bresciani
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy
| | - S Torretta
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy.,Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Italy
| | - L Pignataro
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy.,Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Italy
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Lopes LD, Davis EW, Pereira E Silva MDC, Weisberg AJ, Bresciani L, Chang JH, Loper JE, Andreote FD. Tropical soils are a reservoir for fluorescent Pseudomonas spp. biodiversity. Environ Microbiol 2017; 20:62-74. [PMID: 29027341 DOI: 10.1111/1462-2920.13957] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 10/07/2017] [Accepted: 10/08/2017] [Indexed: 11/30/2022]
Abstract
Fluorescent Pseudomonas spp. are widely studied for their beneficial activities to plants. To explore the genetic diversity of Pseudomonas spp. in tropical regions, we collected 76 isolates from a Brazilian soil. Genomes were sequenced and compared to known strains, mostly collected from temperate regions. Phylogenetic analyses classified the isolates in the P. fluorescens (57) and P. putida (19) groups. Among the isolates in the P. fluorescens group, most (37) were classified in the P. koreensis subgroup and two in the P. jessenii subgroup. The remaining 18 isolates fell into two phylogenetic subclades distinct from currently recognized P. fluorescens subgroups, and probably represent new subgroups. Consistent with their phylogenetic distance from described subgroups, the genome sequences of strains in these subclades are asyntenous to the genome sequences of members of their neighbour subgroups. The tropical isolates have several functional genes also present in known fluorescent Pseudomonas spp. strains. However, members of the new subclades share exclusive genes not detected in other subgroups, pointing to the potential for novel functions. Additionally, we identified 12 potential new species among the 76 isolates from the tropical soil. The unexplored diversity found in the tropical soil is possibly related to biogeographical patterns.
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Affiliation(s)
- Lucas Dantas Lopes
- Department of Soil Science, "Luiz de Queiroz" College of Agriculture, University of São Paulo, Piracicaba, SP, Brazil.,Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, USA
| | - Edward W Davis
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, USA.,Molecular and Cellular Biology Program, Oregon State University, Corvallis, OR 97331, USA
| | - Michele de C Pereira E Silva
- Department of Soil Science, "Luiz de Queiroz" College of Agriculture, University of São Paulo, Piracicaba, SP, Brazil
| | - Alexandra J Weisberg
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, USA
| | - Luana Bresciani
- Department of Soil Science, "Luiz de Queiroz" College of Agriculture, University of São Paulo, Piracicaba, SP, Brazil
| | - Jeff H Chang
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, USA.,Molecular and Cellular Biology Program, Oregon State University, Corvallis, OR 97331, USA
| | - Joyce E Loper
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, USA.,Molecular and Cellular Biology Program, Oregon State University, Corvallis, OR 97331, USA
| | - Fernando D Andreote
- Department of Soil Science, "Luiz de Queiroz" College of Agriculture, University of São Paulo, Piracicaba, SP, Brazil
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Bresciani L, Calani L, Bocchi L, Delucchi F, Savi M, Ray S, Brighenti F, Stilli D, Del Rio D. Bioaccumulation of resveratrol metabolites in myocardial tissue is dose-time dependent and related to cardiac hemodynamics in diabetic rats. Nutr Metab Cardiovasc Dis 2014; 24:408-415. [PMID: 24462050 DOI: 10.1016/j.numecd.2013.09.008] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 09/05/2013] [Accepted: 09/23/2013] [Indexed: 01/23/2023]
Abstract
BACKGROUND AND AIMS Trans-resveratrol (RSV) is a natural compound occurring in different foods and plants, which in vivo is rapidly conjugated with glucuronic acid and sulfate. Despite its demonstrated cardioprotective activity, the bioaccumulation of RSV or its metabolites in cardiac tissue is still unknown. METHODS AND RESULTS Diabetic rats were randomized to 1, 3 or 6 weeks of RSV treatment at two different doses (1 or 5 mg/kg/day). A dose and time-dependent accumulation was observed, with no detectable levels of RSV metabolites found in heart tissues after 1 week and significant concentrations of RSV-3-sulfate and RSV-3-glucuronide after 6 weeks of treatment (0.05 nmol/g of tissue and 0.01 nmol/g of tissue, respectively). Tissue accumulation of RSV metabolites was accompanied by an improvement of cardiac function in long-term diabetes, when myocardial morpho-functional damage is more evident, with an almost complete recovery of all hemodynamic parameters, at the highest RSV dose. CONCLUSION Even if a higher concentration of RSV in tissues cannot be ruled out after constant oral administration, an accumulation coherent with what is usually evaluated in cell based mechanistic studies is largely unattainable and the RSV unconjugated form would not be present in this paradigm. The current investigation provides data on myocardial tissue concentrations of RSV metabolites, after short/medium term RSV treatment. This knowledge constitutes a basic requirement for future studies aimed at reliably defining the molecular pathways underlying RSV-mediated cardioprotective effects and opens up new perspectives for research focused on testing phenolic compounds as adjuvants in degenerative heart diseases.
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Affiliation(s)
- L Bresciani
- The φ(2) Laboratory of Phytochemicals in Physiology, Human Nutrition Unit, Department of Food Science, University of Parma, 43125 Parma, Italy; LS9 Bioactives and Health, Interlab Group, Department of Food Science, University of Parma, Parma, Italy
| | - L Calani
- The φ(2) Laboratory of Phytochemicals in Physiology, Human Nutrition Unit, Department of Food Science, University of Parma, 43125 Parma, Italy; LS9 Bioactives and Health, Interlab Group, Department of Food Science, University of Parma, Parma, Italy
| | - L Bocchi
- Department of Life Sciences, University of Parma, 43124 Parma, Italy
| | - F Delucchi
- Department of Life Sciences, University of Parma, 43124 Parma, Italy
| | - M Savi
- Department of Life Sciences, University of Parma, 43124 Parma, Italy
| | - S Ray
- Cambridge University Hospitals and School of Clinical Medicine, Cambridge, UK
| | - F Brighenti
- The φ(2) Laboratory of Phytochemicals in Physiology, Human Nutrition Unit, Department of Food Science, University of Parma, 43125 Parma, Italy
| | - D Stilli
- Department of Life Sciences, University of Parma, 43124 Parma, Italy.
| | - D Del Rio
- The φ(2) Laboratory of Phytochemicals in Physiology, Human Nutrition Unit, Department of Food Science, University of Parma, 43125 Parma, Italy; LS9 Bioactives and Health, Interlab Group, Department of Food Science, University of Parma, Parma, Italy.
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Geroldi C, Rossi R, Calvagna C, Testa C, Bresciani L, Binetti G, Zanetti O, Frisoni GB. Medial temporal atrophy but not memory deficit predicts progression to dementia in patients with mild cognitive impairment. J Neurol Neurosurg Psychiatry 2006; 77:1219-22. [PMID: 16891386 PMCID: PMC2077364 DOI: 10.1136/jnnp.2005.082651] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND The diagnosis of mild cognitive impairment (MCI) is clinically unhelpful, as many patients with MCI develop dementia but many do not. OBJECTIVE To identify clinical instruments easily applicable in the clinical routine that might be useful to predict progression to dementia in patients with MCI assessed in the outpatient facility of a memory clinic. PARTICIPANTS AND METHODS 52 dementia-free patients (mean (standard deviation) age 70 (6) years; 56% women) with MCI, and 65 healthy controls (age 69 (6) years; 54% women) underwent brain magnetic resonance scan with standardised visual assessment of medial temporal atrophy (MTA) and subcortical cerebrovascular lesions (SVLs). Follow-up assessment occurred 15.4 (SD 3.4) months after baseline to detect incident dementia and improvement, defined as normal neuropsychological performance on follow-up. RESULTS Patients were classified into three groups according to the presence of memory disturbance only (MCI Mem), other neuropsychological deficits (MCI Oth) or both (MCI Mem+). MCI Mem and Mem+ showed MTA more frequently (31% and 47% v 5% and 14% of controls and MCI Oth, p<0.001). 11 patients developed dementia (annual rate 16.5%) and 7 improved on follow-up. The only independent predictor of progression was MTA (odds ratio (OR) 7.1, 95% confidence interval (CI) 1.4 to 35.0), whereas predictors of improvement were the absence of memory impairment (OR 18.5, 95% CI 2.0 to 171.3) and normal MRI scan (OR 10.0, 95% CI 1.7 to 60.2). CONCLUSION Neuropsychological patterns identify groups of patients with MCI showing specific clinical features and risk of progression to dementia. MTA clinically rated with a visual scale is the most relevant predictor of progression and improvement.
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Affiliation(s)
- C Geroldi
- Laboratory of Epidemiology, Neuroimaging and Telemedicine, IRCCS San Giovanni di Dio FBF-The National Center for Research and Care of Alzheimer's Disease, via Pilastroni 4, 25125 Brescia, Italy.
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Walsh DT, Bresciani L, Saunders D, Manca MF, Jen A, Gentleman SM, Jen LS. Amyloid beta peptide causes chronic glial cell activation and neuro-degeneration after intravitreal injection. Neuropathol Appl Neurobiol 2005; 31:491-502. [PMID: 16150120 DOI: 10.1111/j.1365-2990.2005.00666.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
We have previously demonstrated that amyloid beta (Abeta) peptide is acutely toxic to retinal neurones in vivo and that this toxicity is mediated by an indirect mechanism. We have now extended these studies to look at the chronic effect of intravitreal injection of Abeta peptides on retinal ganglion cells (RGC), the projection neurones of the retina and the glial cell response. 5 months after injection of Abeta1-42 or Abeta42-1 there was no significant reduction in RGC densities but there was a significant reduction in the retinal surface area after both peptides. Phosphate-buffered saline (PBS) injection had no effect on retinal size or RGC density. There was a pronounced reduction in the number of large RGCs with a concomitant significant increase in medium and small RGCs. There was no change in cell sizes 5 months after injection with PBS. At 5 months after injection of both peptides, there was marked activation of Muller glial cells and microglia. There was also expression of the major histocompatibility complex (MHC) class II molecule on some of the microglial cells but we saw no evidence of T-cell infiltration into the injected retinas. In order to elucidate potential toxic mechanisms, we have looked at levels of glutamine synthetase and nitric oxide synthase. As early as 2 days after injection we noted that activation of Muller glia was associated with a decrease in glutamine synthetase immuno-reactivity but there was no detectable expression of inducible nitric oxide synthase in any retinal cells. These results suggest that chronic activation of glial cells induced by Abeta peptides may result in chronic atrophy of projection neurones in the rat retina.
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Affiliation(s)
- D T Walsh
- Department of Cellular and Molecular Neuroscience, Division of Neuroscience & Psychological Medicine, Faculty of Medicine, Imperial College, London, UK.
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Bresciani L, Brunello N, Pellicciarî R, Racagni G, Ambrosini A. Effect of novel mGluR antagonists on signal transduction in mesencephalic and striatal neurons in vitro. Neuropharmacology 1996. [DOI: 10.1016/0028-3908(96)84667-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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10
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Ambrosini A, Bresciani L, Fidone F, Brunello N, Racagni G. Expression and functional role of mGluR3 in substantia nigra neurons. Neuropharmacology 1996. [DOI: 10.1016/0028-3908(96)84648-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Ambrosini A, Bresciani L, Brunello N, Racagni G. Cyclic GMP inhibition of metabotropic glutamate receptor-induced phosphoinositide hydrolysis in mesencephalic neurons. Neuropharmacology 1996; 35:1641-3. [PMID: 9025113 DOI: 10.1016/s0028-3908(96)00109-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The effect of cGMP on metabotropic glutamate receptor-induced stimulation of phosphoinositide hydrolysis in mesencephalic neuronal cultures was evaluated by cell incubation with the stable analogue dibutyryl-cGMP (10 microM). A complete blockade of (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid- or quisqualate-induced inositol phosphate formation was observed. Ionotropic glutamate receptors in mesencephalic neurons activate cGMP formation and, through this intracellular messenger, they might control mGluR activity.
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Affiliation(s)
- A Ambrosini
- Center of Neuropharmacology, University of Milan, Italy.
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12
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Ambrosini A, Bresciani L, Fracchia S, Brunello N, Racagni G. Metabotropic glutamate receptors negatively coupled to adenylate cyclase inhibit N-methyl-D-aspartate receptor activity and prevent neurotoxicity in mesencephalic neurons in vitro. Mol Pharmacol 1995; 47:1057-64. [PMID: 7746273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The functional effects of G protein-linked glutamate receptor activation have been studied in mouse mesencephalic neurons in vitro. We have been able to identify two receptor classes, one linked to phosphoinositide hydrolysis and another that inhibits adenylate cyclase. The agonist (1S,3R)-aminocyclopentane-1,3-dicarboxylate (ACPD) affected the two responses with similar potency (EC50 = 2 and 7 microM, respectively). In contrast, (2S,3S,4S)-alpha-(carboxycyclopropyl)glycine selectively decreased adenylate cyclase activity (EC50 = 150 nM), without interfering with the phosphoinositide pathway. Activation of ion channel-linked glutamate receptors in mesencephalic neurons leads to cGMP formation. In this study, we demonstrate that cell pretreatment with ACPD or (2S,3S,4S)-alpha-(carboxycyclopropyl)glycine prevented, in a dose-dependent fashion, N-methyl-D-aspartate (NMDA)-induced cGMP formation but not the kainate-stimulated response. The pharmacological profile suggests that receptors that are negatively coupled to adenylate cyclase are responsible for this effect. Coexposure of neurons to ACPD and Ba2+, a K+ channel blocker, counteracted the ACPD-induced blockade of NMDA receptors, suggesting that activation of K+ conductances could be involved in the post-transduction events triggered by metabotropic receptors in the mesencephalon. Neuronal treatment with NMDA for 10 min caused a reduction in mitochondrial activity. Direct inhibition of nitric oxide synthase with the inhibitor NG-nitro-L-arginine or removal of extracellular nitric oxide with reduced hemoglobin did not prevent this metabolic impairment, thus excluding a role for nitric oxide in this test for excitotoxicity. On the contrary, the mitochondrial function was maintained when neurons exposed to NMDA were preincubated with metabotropic receptor agonists. To summarize, our results suggest that metabotropic receptors that are negatively coupled to adenylate cyclase exert modulatory control specifically on NMDA receptor activity. This event could also contribute to the reduction of neurotoxic effects due to NMDA receptor hyperactivity.
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Affiliation(s)
- A Ambrosini
- Center of Neuropharmacology, University of Milan, Italy
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Bresciani L, Clarke G, Dondio G, Orlandi V, Racagni G, Ambrosini A. Delta opioid receptor activation in cortical neuronsin vitro. Pharmacol Res 1995. [DOI: 10.1016/1043-6618(95)86726-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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14
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Ambrosini A, Bresciani L, Fracchia S, Brunello N, Racagni G. Metabotropic glutamate receptors inhibit NMDA receptor activity and prevent neurotoxicity in mesencephalic neuronsin vitro. Pharmacol Res 1995. [DOI: 10.1016/1043-6618(95)87440-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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15
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Bresciani L, Puricelli C, Vercesi G, Beffagna B, Iapichino G, Erculani P, Salvago G, Sircana A, Baiocchi L, Mascarello P, Pellegrini GF. Cardio-circulatory assistance with an artificial, peripheral, external ventricle: hemodynamics. J Cardiovasc Surg (Torino) 1974; 15:425-37. [PMID: 4841612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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16
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Taschieri AM, Peri G, Rossi AL, Bresciani L. [Splenoportography in the diagnosis of pancreatic neoplasms]. Radiol Med 1970; 56:1121-32. [PMID: 5209307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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