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In 2008, an international project was designed to improve the food supply of the poor populations of West and Central Africa by developing cultures of different species of Pachyrhizus. Indeed, these plants grow quickly; they are resistant to many environmental stresses as periods of drought and plentiful rains and they don't need a lot of nitrate fertilizers. Furthermore, they could constitute an interesting nutritional source: their tubers contain mainly sugars and starch but also contain proteins (6 to 18 % d.m.), and minerais as Zn and Fe. The Pachyrhizus seeds are also interesting, because they are rich in proteins (28, 3%), in lipids (26,8 %) as well as in sugars and minerais .However these seeds are known to contain rotenone, a natural molecule previously used as insecticide inhibiting the respiratory mitochondrial chain. A part of its toxicity could touch mammals through the generation of an oxidative stress which was previously demonstrated at the cellular level.The purpose of the research realized at the Phannacognosy laboratory of LORI of the UCL is to study the thermal degradation of rotenone to reduce or even eliminate the rotenone of the Pachyrhizus seeds. That could allow their use for the African populations to improve their nutritional quality as well as generate an additional income for cultivators. Indeed, the sensitivity of rotenone to light was widely studied but its thermal sensitivity was Jess studied.First of ail the thermal degradation of the standard rotenone was evaluated. When the rotenone is heated for three hours at 100°C in methanol, a degradation of 22% is obtained. Then, different kinds of processes and traditional culinary preparations were realized in Benin, in IITA and INRAB laboratories in Abomey Calavi supervised by or Kerstin Hell and by Mr Charles Pomalegni. The contents in rotenone of these recipes were then quantified by a method associating microwave extraction, solid phase extraction (SPE) and an HPLC-UV. The results showed an important degradation of rotenone varying from 20 to 80 % for exemple when the seeds are grilled for one hour at 90°C on a heating plate.To verify if the thermal degradation of rotenone doesn't lead to the formation of more toxic compounds, analysis by mass spectrometry were realized to identify the rotenone degradation compounds. The three main degradation compounds are isomers of rotenone which was confirmed by further studies. En 2008, un projet international visant à améliorer l'alimentation des populations pauvres d'Afrique Occidentale et Centrale par le développement de la culture de diverses espèces de Pachyrhizus a été mis en place. En effet, ces espèces poussent rapidement, sont résistantes à des stress environnementaux variés comme une alternance de périodes de sécheresses et de pluies abondantes et sont peu exigeantes en engrais azotés. De plus, elles pourraient constituer une source nutritionnelle intéressante : leurs tubercules sont constitués principalement de sucres et d'amidon mais aussi de Fe, de Zn, et de 6 à 18% de protéines (m .s.). Les graines de haricot igname sont, elles aussi, intéressantes car elles sont riches en protéines (28,3%), en lipides (26,8%) ainsi qu'en sucres et sels minéraux. Cependant, ces graines sont connues pour contenir de la roténone, une molécule naturelle auparavant utilisée comme insecticide, inhibant la chaîne respiratoire mitochondriale. Une partie de cette toxicité pourrait s'exercer vis-à-vis des mammifères à travers la génération d'un stress oxydatif qui a pu être démontré au niveau cellulaire. Le but des recherches effectuées dans le cadre du travail d'étudiant chercheur et réalisées dans le laboratoire de pharmacognosie du LDRI de l'UCL est d'étudier la dégradation thermique de la roténone afin de réduire, voire d'éliminer la roténone des graines de Pachyrhizus. Ceci pourrait permettre leur utilisation par les populations africaines afin d'améliorer leur qualité nutritionnelle ainsi que de générer une source de revenu complémentaire.Dans un premier temps, la dégradation thermique de la roténone standard a été évaluée. En effet, la sensibilité de la roténone à la lumière a été largement étudiée par contre sa sensibilité à la chaleur a fait l'objet de moins de travaux. Une dégradation de 22% a été obtenue lors du chauffage de celle-ci dans du méthanol à 100°C pendant trois heures. Ensuite, différents traitements thermiques avec ou sans le tégument externe de la graine ainsi que des préparations culinaires traditionnelle s ont été réalisés au Bénin, aux laboratoires de l'Institut International de l'Agriculture Tropicale (IITA) et de l'Institut National de la Recherche Agricole du Bénin (INRAB) à Abomey Calavi, sous la direction du Dr Kerstin Hell et de Mr Charles Pomalegni. Le contenu en roténone de ces différentes recettes a ensuite été quantifié grâce à une méthode associant extraction assistée par micro-ondes, purification par SPE (solid phase extraction) et dosage proprement dit par HPLC-UV. Les résultats ont montré une importante dégradation de la roténone variant de 20 à 80% pour certaines préparations comme le fait de griller des graines entières pendant 1 heure à 90°C sur une plaque chauffante.Afin de vérifier si la dégradation thermique de la roténone ne s'accompagne pas de la formation de composés plus toxiques, des analyses en spectrométrie de masse ont ensuite été réalisées pour caractériser les composés de dégradation de la roténone. Les trois principaux composés de dégradation de la roténone sont des isomères de celle-ci, ce qui a été confirmé par des travaux ultérieurs.

Pachyrhizus --- Food Assistance --- Rotenone

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Pesticide crops --- Rotenone --- Analytical methods --- toxicity

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thesis --- Fabaceae --- Leguminosae --- insecticides --- pharmacology --- Derris --- Lonchocarpus --- Millettia --- Pachyrhizus --- rotenone insensitive route --- toxicology

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The focus on dopamine-sensitive motor symptoms, in association with the improvement of motor complications in the heterogeneous disease entity Parkinson's disease, has led to a certain standstill in research. This Special Issue provides new concepts and new ideas on the pathogenesis, genetics, and clinical maintenance of Parkinson's disease and related disorders. Not only new experimental findings, but also clinical outcomes, case series, and research on alternative, non-pharmacological therapies are included. The objective is to bridge the currently increasing gap between experimental and clinical research on Parkinson's disease and related disorders.

microRNAs --- disease-modifying effects --- SH-SY5Y --- inpatient treatment --- sphingolipids --- neurodegeneration --- magnetic resonance spectroscopy --- MO3.13 --- schizophrenia --- epigenetics --- long-chain acylcarnitine --- molecular mimicry --- curli --- multimodal complex treatment --- chlorogenic acid --- glycerophospholipids --- caffeic acid --- lipoproteins --- myenteric plexus --- neurometabolites --- HOG --- immature oligodendrocyte --- autophagy --- oligodendrocyte --- hypochlorite --- alpha-synuclein --- microbiome --- glucocerebrosidase --- Lewy Body Dementia --- brain iron --- mesenchymal stem cells --- fatty acid ?-oxidation --- GABA --- enteric glial cell --- gut-brain axis --- microbiota --- REM sleep behavior disorders --- redox cycling --- magnetic resonance imaging --- differentiation --- ?-synuclein-mediated pathology --- Parkinson disease --- Gaucher’s disease --- metallothionein --- [123I]FP-CIT-SPECT --- dopaminergic neuron --- mature oligodendrocyte --- glycerolipids --- spectroscopy --- neuroinflammation --- exosomes --- immunotherapy --- DNA methylation --- sterol lipids --- nigral cells --- cell line --- cysteinyl-dopamine --- myelin --- parkinsonisms --- multiple sclerosis --- rotenone --- brain --- fatty acyls --- Krabbe’s disease --- neuroprotection --- DAT --- motor dysfunction --- secretome --- multiprofessional therapy --- Parkinson’s disease --- oxidative stress --- alpha-Synuclein

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Positron emission tomography (PET) and single-photon emission computed tomography (SPECT) are in vivo molecular imaging methods which are widely used in nuclear medicine for diagnosis and treatment follow-up of many major diseases. These methods use target-specific molecules as probes, which are labeled with radionuclides of short half-lives that are synthesized prior to the imaging studies. These probes are called radiopharmaceuticals. The use of PET and SPECT for brain imaging is of special significance since the brain controls all the body’s functions by processing information from the whole body and the outside world. It is the source of thoughts, intelligence, memory, speech, creativity, emotion, sensory functions, motion control, and other important body functions. Protected by the skull and the blood–brain barrier, the brain is somehow a privileged organ with regard to nutrient supply, immune response, and accessibility for diagnostic and therapeutic measures. Invasive procedures are rather limited for the latter purposes. Therefore, noninvasive imaging with PET and SPECT has gained high importance for a great variety of brain diseases, including neurodegenerative diseases, motor dysfunctions, stroke, epilepsy, psychiatric diseases, and brain tumors. This Special Issue focuses on radiolabeled molecules that are used for these purposes, with special emphasis on neurodegenerative diseases and brain tumors.

Research & information: general --- Biology, life sciences --- SV2A --- SV2B --- SV2C --- microPET --- [18F]UCB-H --- epilepsy --- PBIF --- distribution volume --- blocking assay --- preclinical imaging --- Alzheimer’s disease (AD) --- network measure --- graph theory --- brain network --- positron emission tomography (PET) --- persistent homology --- Phosphodiesterase 2A (PDE2A) --- Positron Emission Tomography (PET) --- Benzoimidazotriazine (BIT) --- fluorinated --- Mouse Liver Microsomes (MLM) --- cyclic nucleotide phosphodiesterase --- PDE2A radioligand --- nitro-precursor --- fluorine-18 --- in vitro autoradiography --- PET imaging --- opioid receptors --- positron emission tomography --- radiotracers --- μOR-, δOR-, κOR- and ORL1-ligands --- movement disorders --- pain --- drug dependence --- GBM --- biomarkers --- Sigma 1 --- Sigma 2 --- PD-L1 --- PARP --- IDH --- Alzheimer’s disease --- Parkinson’s disease --- β-amyloid plaques --- neurofibrillary tangles --- α-synucleinopathy --- diagnostic imaging probes --- orexin receptors --- PET --- radiotracer --- imaging --- alpha 7 --- nicotinic acetylcholine receptors --- nAChR --- autoradiography --- amino acid --- FET --- FACBC --- FDOPA --- immunoPET --- molecular imaging --- glioma --- brain metastases --- adenosine A2A receptor --- rotenone-based mouse model --- [18F]FESCH --- two-step one-pot radiosynthesis