Abstracts of the fourth brainstorming research assembly for young neuroscientists (BraYn), Italy, 20–22 October 2021

On behalf of the BraYn Association, we are pleased to present the Abstracts of the Fourth Brainstorming Research Assembly for Young Neuroscientists, which was held from 20–22 October 2021. We congratulate all the presenters on their research work and contribution

Betaine-The dark knight of the brain

The role of betaine in the liver and kidney has been well documented, even from the cellular and molecular point of view. Despite literature reporting positive effects of betaine supplementation in Alzheimer's, Parkinson's and schizophrenia, the role and function of betaine in the brain are little studied and reviewed. Beneficial effects of betaine in neurodegeneration, excitatory and inhibitory imbalance and against oxidative stress in the central nervous system (CNS) have been collected and analysed to understand the main role of betaine in the brain. There are many 'dark' aspects needed to complete the picture. The understanding of how this osmolyte is transported across neuron and glial cells is also controversial, as the expression levels and functioning of the known protein capable to transport betaine expressed in the brain, betaine-GABA transporter 1 (BGT-1), is itself not well clarified. The reported actions of betaine beyond BGT-1 related to neuronal degeneration and memory impairment are the focus of this work. With this review, we underline the scarcity of detailed molecular and cellular information about betaine action. Consequently, the requirement of detailed focus on and study of the interaction of this molecule with CNS components to sustain the therapeutic use of betaine

Bile acid interactions with neurotransmitter transporters

Synthesized in the liver from cholesterol, the bile acids (BAs) primary role is emulsifying fats to facilitate their absorption. BAs can cross the blood-brain barrier (BBB) and be synthesized in the brain. Recent evidence suggests a role for BAs in the gut-brain signaling by modulating the activity of various neuronal receptors and transporters, including the dopamine transporter (DAT). In this study, we investigated the effects of BAs and their relationship with substrates in three transporters of the solute carrier 6 family. The exposure to obeticholic acid (OCA), a semi-synthetic BA, elicits an inward current (I-BA) in the DAT, the GABA transporter 1 (GAT1), and the glycine transporter 1 (GlyT1b); this current is proportional to the current generated by the substrate, respective to the transporter. Interestingly, a second consecutive OCA application to the transporter fails to elicit a response. The full displacement of BAs from the transporter occurs only after exposure to a saturating concentration of a substrate. In DAT, perfusion of secondary substrates norepinephrine (NE) and serotonin (5-HT) results in a second OCA current, decreased in amplitude and proportional to their affinity. Moreover, co-application of 5-HT or NE with OCA in DAT, and GABA with OCA in GAT1, did not alter the apparent affinity or the I-max, similar to what was previously reported in DAT in the presence of DA and OCA. The findings support the previous molecular model that suggested the ability of BAs to lock the transporter in an occluded conformation. The physiological significance is that it could possibly avoid the accumulation of small depolarizations in the cells expressing the neurotransmitter transporter. This achieves better transport efficiency in the presence of a saturating concentration of the neurotransmitter and enhances the action of the neurotransmitter on their receptors when they are present at reduced concentrations due to decreased availability of transporters

Trafficking of the glutamate transporter is impaired in LRRK2-related Parkinson's disease

The Excitatory Amino Acid Transporter 2 (EAAT2) accounts for 80% of brain glutamate clearance and is mainly expressed in astrocytic perisynaptic processes. EAAT2 function is finely regulated by endocytic events, recycling to the plasma membrane and degradation. Noteworthy, deficits in EAAT2 have been associated with neuronal excitotoxicity and neurodegeneration. In this study, we show that EAAT2 trafficking is impaired by the leucine-rich repeat kinase 2 (LRRK2) pathogenic variant G2019S, a common cause of late-onset familial Parkinson’s disease (PD). In LRRK2 G2019S human brains and experimental animal models, EAAT2 protein levels are significantly decreased, which is associated with elevated gliosis. The decreased expression of the transporter correlates with its reduced functionality in mouse LRRK2 G2019S purified astrocytic terminals and in Xenopus laevis oocytes expressing human LRRK2 G2019S. In LRRK2 G2019S knock-in mouse brain, the correct surface localization of the endogenous transporter is impaired, resulting in its interaction with a plethora of endo-vesicular proteins. Mechanistically, we report that pathogenic LRRK2 kinase activity delays the recycling of the transporter to the plasma membrane via Rabs inactivation, causing its intracellular re-localization and degradation. Taken together, our results demonstrate that pathogenic LRRK2 interferes with the physiology of EAAT2, pointing to extracellular glutamate overload as a possible contributor to neurodegeneration in PD

Social franchising and social farming, for promoting the co-production of knowledge and values: the IBF case

Social franchising is primarily a method to transfer knowledge from one established enterprise to another that wants to achieve the same social and economic goals. The social franchise is an adaptation of a commercial franchise in which the developer of a successfully tested social concept (franchisor) ena-bles others (franchisees) to replicate the model using the tested system and the brand name to achieve a social benefit. In fact, social franchising combines social objectives (sharing learning and methodologies for greater social impact) with economic objectives. This link is the reason that many consider social fran-chising to be a potential tool for the growth of social farming initiatives that introduce the co-production of private and public values. The paper opens with an overview of social franchising. Then it explains meth-odology used for the creation of social franchising for social farming (IBF) and discusses how this tool can be able to facilitate social innovation in agriculture

The “www” of Xenopus laevis Oocytes: The Why, When, What of Xenopus laevis Oocytes in Membrane Transporters Research

After 50 years, the heterologous expression of proteins in Xenopus laevis oocytes is still essential in many research fields. New approaches and revised protocols, but also classical methods, such as the two-electrode voltage clamp, are applied in studying membrane transporters. New and old methods for investigating the activity and the expression of Solute Carriers (SLC) are reviewed, and the kinds of experiment that are still useful to perform with this kind of cell are reported. Xenopus laevis oocytes at the full-grown stage have a highly efficient biosynthetic apparatus that correctly targets functional proteins at the defined compartment. This small protein factory can produce, fold, and localize almost any kind of wild-type or recombinant protein; some tricks are required to obtain high expression and to verify the functionality. The methodologies examined here are mainly related to research in the field of membrane transporters. This work is certainly not exhaustive; it has been carried out to be helpful to researchers who want to quickly find suggestions and detailed indications when investigating the functionality and expression of the different members of the solute carrier families

Italian Social Farming: the Network of Coldiretti and Campagna Amica

For the last ten years, Social farming (SF) has become an innovative practice able to connect multifunctional agriculture and novel social services for urban and rural areas in Italy and the EU. By looking at the experience from Italy, it is possible to note that SF has not developed homogeneously along the national territory. It is characterized by a wide range of practices and activities related to the development of a welfare in which several topics such as subsidiarity, the value of relationship, and co-production find multiple meanings and applications. This paper provides a further contribution to the knowledge on this type of activity and opens the way to deeper considerations on the topic. The information reported in this study refers to a project born in 2018 and carried out by Fondazione Campagna Amica, a foundation promoted by Coldiretti, the main organization of agricultural entrepreneurs in Italy. This paper focuses on the analysis of data collected during this project, through in-depth interviews carried out from July 2018 to March 2019 among 229 agricultural enterprises, as well as meetings with representatives of the regional offices of Coldiretti that are involved in SF. This study aims to reach a better understanding of the development of SF in Italy through the perspective of a national network of farmers and to compare SF practices across regions in order to examine their similarities and differences. The most important results show big individual farms with a great variety of agricultural activities and livestock systems, with a clear predominance of horticulture. These SF farms mainly provide direct sales and educational activities and are involved in training and job placement services

Trafficking of the glutamate transporter is impaired in LRRK2-related Parkinson's disease

: The Excitatory Amino Acid Transporter 2 (EAAT2) accounts for 80% of brain glutamate clearance and is mainly expressed in astrocytic perisynaptic processes. EAAT2 function is finely regulated by endocytic events, recycling to the plasma membrane and degradation. Noteworthy, deficits in EAAT2 have been associated with neuronal excitotoxicity and neurodegeneration. In this study, we show that EAAT2 trafficking is impaired by the leucine-rich repeat kinase 2 (LRRK2) pathogenic variant G2019S, a common cause of late-onset familial Parkinson's disease (PD). In LRRK2 G2019S human brains and experimental animal models, EAAT2 protein levels are significantly decreased, which is associated with elevated gliosis. The decreased expression of the transporter correlates with its reduced functionality in mouse LRRK2 G2019S purified astrocytic terminals and in Xenopus laevis oocytes expressing human LRRK2 G2019S. In LRRK2 G2019S knock-in mouse brain, the correct surface localization of the endogenous transporter is impaired, resulting in its interaction with a plethora of endo-vesicular proteins. Mechanistically, we report that pathogenic LRRK2 kinase activity delays the recycling of the transporter to the plasma membrane via Rabs inactivation, causing its intracellular re-localization and degradation. Taken together, our results demonstrate that pathogenic LRRK2 interferes with the physiology of EAAT2, pointing to extracellular glutamate overload as a possible contributor to neurodegeneration in PD

Trafficking of the glutamate transporter is impaired in LRRK2-related Parkinson's disease

21sinoneThe Excitatory Amino Acid Transporter 2 (EAAT2) accounts for 80% of brain glutamate clearance and is mainly expressed in astrocytic perisynaptic processes. EAAT2 function is finely regulated by endocytic events, recycling to the plasma membrane and degradation. Noteworthy, deficits in EAAT2 have been associated with neuronal excitotoxicity and neurodegeneration. In this study, we show that EAAT2 trafficking is impaired by the leucine-rich repeat kinase 2 (LRRK2) pathogenic variant G2019S, a common cause of late-onset familial Parkinson's disease (PD). In LRRK2 G2019S human brains and experimental animal models, EAAT2 protein levels are significantly decreased, which is associated with elevated gliosis. The decreased expression of the transporter correlates with its reduced functionality in mouse LRRK2 G2019S purified astrocytic terminals and in Xenopus laevis oocytes expressing human LRRK2 G2019S. In LRRK2 G2019S knock-in mouse brain, the correct surface localization of the endogenous transporter is impaired, resulting in its interaction with a plethora of endo-vesicular proteins. Mechanistically, we report that pathogenic LRRK2 kinase activity delays the recycling of the transporter to the plasma membrane via Rabs inactivation, causing its intracellular re-localization and degradation. Taken together, our results demonstrate that pathogenic LRRK2 interferes with the physiology of EAAT2, pointing to extracellular glutamate overload as a possible contributor to neurodegeneration in PD.openIovino, Ludovica; Giusti, Veronica; Pischedda, Francesca; Giusto, Elena; Plotegher, Nicoletta; Marte, Antonella; Battisti, Ilaria; Di Iacovo, Angela; Marku, Algerta; Piccoli, Giovanni; Bandopadhyay, Rina; Perego, Carla; Bonifacino, Tiziana; Bonanno, Giambattista; Roseti, Cristina; Bossi, Elena; Arrigoni, Giorgio; Bubacco, Luigi; Greggio, Elisa; Hilfiker, Sabine; Civiero, LauraIovino, Ludovica; Giusti, Veronica; Pischedda, Francesca; Giusto, Elena; Plotegher, Nicoletta; Marte, Antonella; Battisti, Ilaria; Di Iacovo, Angela; Marku, Algerta; Piccoli, Giovanni; Bandopadhyay, Rina; Perego, Carla; Bonifacino, Tiziana; Bonanno, Giambattista; Roseti, Cristina; Bossi, Elena; Arrigoni, Giorgio; Bubacco, Luigi; Greggio, Elisa; Hilfiker, Sabine; Civiero, Laur