Search

Capsaicin is a naturally occurring alkaloid derived from Chili peppers fruits. Using the two-electrode voltage-clamp technique in Xenopus oocyte expression system, actions of capsaicin on the functional properties of α

In 2013 excavations near Vernègues (Bouches-du Rhône), “ Cazan-Le Clos du Moulin”, revealed an important occupation site dating from the Middle Neolithic (late Chassey culture). The village of Vernègues is located just south of the Massif du Luberon, approximately 60 km north-west of Marseille and the Mediterranean. The area excavated, a little over one hectare, is located in the centre of a small valley which joins the valley of the Durance just to the north. This valley is remarkable for the density of Neolithic remains and “ Cazan-Le Clos du Moulin” is situated in the centre of a cluster of sites. The different sites form a discontinuous network across the floor of the valley, which is undoubtedly linked to the network of watercourses which drain the valley. While no occupation ground was uncovered during the excavation, over 600 archaeological features were preserved. These features record one of the first structured dwelling sites for this period in the south of France. The occupation of this site has been dated by eight radiocarbon dates (4100 -3800 BCE) and a large assemblage of archaeological finds, which confirm the attribution to the late Chassey culture. The site contained many pits, five wells and a concentration of twenty burnt stone combustion features, which are typical of this period. Through analysis of these structures we observe how two pairs of wells seem to have functioned together, particularly in their secondary use as middens. The burnt stone combustion features are all circular and organised into four sub-parallel lines. These features group two different types of hearths, which may reflect a chronological difference or differences in use. However, the most notable aspect of this site resides in the discovery of many postholes and foundation pits, which trace the outline of at least fifteen different architectural structures. These are the earliest buildings recorded for the late Chassey in the south of France. They notably consist of ten houses which were implanted on well-preserved postholes. These structures repeat the same overall plan, based around a dozen posts organised into two aisles, with a probable ridge beam extending beyond the ridge purlin. Two smaller posts in front of the southern gable end probably indicate the location of an entrance. The surface area of these buildings varies between 80 and 180 m ² . There are few comparable examples for these structures for this period and they are markedly distinct from other examples in France or in northern Italy, which are generally rectangular in plan and frequently have foundation trenches. In addition, three other architectural structures have been identified, which are defined by a series of very large foundation pits. The pits are rectangular in plan with asymmetric profiles (at times triangular, occasionally trapezoidal) : they can be up to 2 m deep with an over-cut at the base. We find even fewer archaeological parallels for these buildings. However their construction clearly demanded a significant investment of time and effort, which could indicate the coordination of a group or community of individuals. All of these buildings follow a plan which was clearly collectively predefined ; all the buildings are orientated NW-SE, which coincides with the prevailing wind in the valley. Moreover, the distribution of these postholes and pits indicates that several houses were completely rebuilt in the same place, up to two to three times. Each new phase of construction was preceded by the partial deconstruction of the remains of the previous phase. We note that some of the posts had clearly begun to decompose in situ, prior to being burnt and/ or removed. Finally, some of the pits/ postholes from the previous phases were backfilled with stones and broken fragments of querns. Analysis of the archaeological finds has not allowed us to establish a relative chronology between these different buildings or the diverse features. However, it has enabled us to define several zones of activity, specifically related to the working of flint and obsidian. The obsidian comes from Sardinia and we have observed elements associated with shaping and working nuclei as well as debitage from a knapping area which were found in a well. Obsidian is not the only example of imported material found ; it is accompanied by several ceramic and earthenware objects (including a loom weight) and a copper awl, all of which probably originate from northern Italy. Furthermore, analysis of the querns recovered from the postholes and analysis of the marks on the worked flints indicate agricultural activities related to grain farming. The faunal remains were almost exclusively recovered from the deposits infilling the wells. These remains record the importance of caprines in the livestock, indicating pastoral activities were also important at Cazan, as at many other sites of the same period. These different activities imply a domestic occupation, seemingly permanent, in a predominantly anthropogenically modified landscape (based on malacological analysis). The preliminary analysis of the snail assemblage indicates an open environment during the late Chassey culture, and this observation seems to be confirmed by the charcoal analysis. Furthermore, the study of the charcoal from the postholes and hearths allows us to distinguish the selection of different species of wood : oak is used for the posts while strawberry tree (arbutus unedo) is used as fuel. These results suggest the attachment of the Chassey population to this place and the surrounding landscape, which they occupied and reoccupied several times over 300 years. While an important part of their activity was based around a mobile lifestyle and pastoral management, this site allows us to consider the concept of a Neolithic village. These first results presented here renew the debate and research concerning the character of the occupation of this landscape during this period., Une fouille réalisée en 2013 à Cazan «le Clos du Moulin » Vernègues (Bouches-du Rhône) a permis de mettre en évidence une importante occupation du Chasséen récent en fond de vallon. Aucun niveau de sol n’a été retrouvé, mais plus de 600 structures en creux permettent de documenter un des premiers sites d’habitat structuré de cette période dans le Sud de la France. Les attributions chronologiques reposent sur huit datations au 14C comprises en 4100 et 3800 avant notre ère et sur un abondant mobilier archéologique qui concorde avec l’attribution à une étape récente du Chasséen. Le gisement livre plusieurs fosses, des puits et une concentration de structures à pierres chauffées, mais aussi et surtout de nombreux trous de poteau et fosses d’implantation qui permettent de restituer les plans d’environ quinze bâtiments. Ces derniers correspondent notamment à dix édifices standards ; trois ensembles architecturaux plus imposants s’insèrent au sein de cette organisation et traduisent sans doute la présence d’édifices socialement plus valorisés. L’analyse du mobilier archéologique ne permet pas de déterminer assurément de chronologies relatives au sein de ces structures et aménagements, mais elle met en évidence plusieurs zones d’activités privilégiées en particulier pour le travail du silex et de l’obsidienne. Ces activités signent une occupation domestique a priori pérenne au sein d’un paysage largement anthropisé et maitrisé d’après les observations anthracologiques et malacologiques. L’ensemble de ces résultats tend à prouver l’attachement des populations chasséennes à ce territoire où elles se sont installées et ont vécues. Ce site permet donc enfin d’approcher pleinement la notion de village pour le Chasséen récent., Moreau Clément, Léa Vanessa, Delhon Claire, Magnin Frédéric, Howarth Luke, Linton Jimmy, Pacotte Lucas, Foucras Sylvain, Nicosia Cristiano, Le Bourdonnec François-Xavier, Gerez Julie, Sénépart Ingrid. Un village chasséen dans le Sud de la France: Cazan «le Clos du Moulin», Vernègues (Bouches-du-Rhône). In: Bulletin de la Société préhistorique française, tome 114, n°1, 2017. pp. 53-91.

Capsaicin is a naturally occurring alkaloid derived from Chili peppers fruits. Using the two-electrode voltage-clamp technique in Xenopus oocyte expression system, actions of capsaicin on the functional properties of α7 subunit of the human nicotinic acetylcholine (α7 nACh) receptor were investigated. Ion currents activated by ACh (100 μM) were reversibly inhibited with an IC50 value of 8.6 μM. Inhibitory actions of capsaicin was independent of membrane potential. Furthermore, Ca2+-dependent Cl- channels expressed endogenously in oocytes were not involved in inhibitory actions of capsaicin. In addition, increasing the ACh concentrations could not reverse the inhibitory effects of capsaicin. Importantly, specific binding of [125I] α-bungarotoxin remained unaltered by capsaicin suggesting that its effect is noncompetitive. Whole cell patch-clamp technique was performed in CA1 stratum radiatum interneurons of rat hippocampal slices. Ion currents induced by choline, a selective-agonist of α7-receptor, were reversibly inhibited by 10 min bath application of capsaicin (10 μM). Collectively, results of our investigation indicate that the function of the α7-nACh receptor expressed in Xenopus oocytes and in hippocampal interneurons are inhibited by capsaicin.

International audience; ``Cazan-Le clos du Moulin'' is an open-air Middle Neolithic site located in the South of France near the village of Vernegues. The excavation of this site has, for the first time in the area, allowed us to reconstruct up to a dozen domestic buildings from the late Chassey culture (4100-3800 BCE), arranged around an area occupied by heated stone combustion structures. Because of the partial erosion of the archaeological horizons, artefacts and ecofacts related to the Neolithic occupation were only found in the fills of structures. Charcoal analysis was carried out on samples from the postholes, the heated-stone hearths and a well. The anthracological results show a selection of natural resources depending on the use of the wood: timber or fuel. The size required for the posts can restrict the scope of the species suitable for timber: oak seems to be preferred for that purpose. On the contrary, the choice of fuel wood seems to be less constrained by technical limitations. Nevertheless, one particular species, Arbutus unedo, accounts for the bulk of the wood gathered for fuel supply, however it was certainly not the only woody resource available during the Middle Neolithic. Overall, charcoal analysis at Cazan-Le Clos du Moulin shows that wood harvesting - as recorded in the fills of structures - is selective. This selection could be imposed by purely technical requirements that we can only partly perceive or by cultural necessity which remains beyond our understanding, but, beyond this, the choices are probably guided by land and vegetation resource management in order to permit the coexistence of various wood-consuming activities in a single territory and to favor the exploitation of easily accessible fuel. (C) 2016 Elsevier Ltd and INQUA. All rights reserved.

International audience