Understanding the mechanisms underlying oro-gustatory detection of dietary fat is critical for the prevention and treatment of obesity. The lipid-binding glycoprotein CD36, which is expressed by circumvallate papillae (CVP) of the mouse tongue, has been implicated in oro-gustatory perception of dietary lipids. Here, we demonstrate that stromal interaction molecule 1 (STIM1), a sensor of Ca 2+ depletion in the endoplasmic reticulum, mediates fatty acid-induced Ca 2+ signaling in the mouse tongue and fat preference. We showed that linoleic acid (LA) induced the production of arachidonic acid (AA) and lysophosphatidylcholine (Lyso-PC) by activating multiple phospholipase A 2 isoforms via CD36. This activation triggered Ca 2+ influx in CD36-positive taste bud cells (TBCs) purified from mouse CVP. LA also induced the production of Ca 2+ influx factor (CIF). STIM1 was found to regulate LA-induced CIF production and the opening of multiple store-operated Ca 2+ (SOC) channels. Furthermore, CD36-positive TBCs from Stim1 -/-mice failed to release serotonin, and Stim1 -/-mice lost the spontaneous preference for fat that was observed in wild-type animals. Our results suggest that fatty acid-induced Ca 2+ signaling, regulated by STIM1 via CD36, might be implicated in oro-gustatory perception of dietary lipids and the spontaneous preference for fat. IntroductionThe sense of taste informs the organism about the quality of ingested food. Five basic taste modalities, e.g., sweet, sour, bitter, salty, and umami, have so far been identified (1). Recent compelling evidence from rodents raises the possibility of an additional sixth taste modality devoted to the perception of lipids (2-4) that are released by the action of lingual lipases, present in the salivary secretions (5). Fukuwatari et al. (6) and Laugerette et al. (2) have documented the expression of the receptor-like lipid-binding protein CD36 in rat and mouse circumvallate papillae (CVP), respectively. Laugerette et al. (2) have provided the first evidence for the involvement of lingual CD36 in dietary lipid perception in the mouse. Indeed, Cd36 gene inactivation completely abolished the spontaneous preference for long-chain fatty acids (LCFAs) observed in wild-type mice. This effect is lipid specific, since the preference for sweet and aversion to bitterness reported in controls were not altered in Cd36-null mice. These observations regarding the implication of CD36 in the perception of lipid taste have also been confirmed by other investigators (7).The coupling of CD36 cell signaling to a downstream second messenger cascade has been explored in mouse taste bud cells (TBCs) (3,8). The experiments conducted on CD36-positive TBCs purified from mouse CVP demonstrated that linoleic acid (LA), an LCFA, induced increases in free intracellular calcium concentrations, [Ca 2+ ] i by binding to CD36 (3). We have reported that LCFAs induced the production of inositol-1,4,5-trisphosphate (IP 3 ) and, consequently, recruited Ca 2+ from the endoplasmic reticulum, followed by Ca 2+ inf...

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It has been well propounded that there exists five basic taste modalities, e.g., sweet, sour, bitter, salty and umami. Recent compelling evidence from rodents and human beings raises the possibility for an additional sixth taste modality devoted to the perception of lipids. A number of studies have suggested that lingual CD36, a glycoprotein, mainly expressed by circumvallate papillae of the tongue, might be implicated in the perception of dietary fat taste. G protein-coupled receptors (GPCRs) are important signaling molecules for many aspects of cellular function. It has been recently shown that these receptors particularly GPR40 and GPR120 might also be involved in lipid taste perception. In this article, we highlight the cell activation mechanisms, responsible for the downstream cell signaling which might help understand the lipid-mediated regulation of feeding behavior, critically involved in the development of several diseases like obesity and other metabolic disorders. We also raise the question whether lipid gustatory cells can be the target of anti-obesity strategies.

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Study of surface contamination of bovine carcasses in the Kandi slaughter zone, northern Benin ABSTRACT In this work, we have evaluated the bacterial quality of bovine carcasses in the kandi area in northern Benin, following the technical indications specified in a memo from the veterinary services on the microbiological criteria for carcasses. . For a total aerobic mesophilic flora of 106 cfu / cm 2 we found a large number of gram (+) bacilli (40.74%) and Gram cocci (+) (38.88%). The Gram (-) bacilli were 8.14% and the fungi 12.24%.

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Phytopathogenic fungi decrease crop yield and quality and cause crop damage.   The present work aims to study the effectiveness of certain extracts of medicinal and food plants (EtOH, DCM) that are present in the Republic of Benin on the mycelial growth of toxigenic molds responsible for the degradation of cereals. Ethanol, dichloromethane and aqueous extracts were studied in vitro for their antifungal activities against Fusarium graminearum using microdilution methods.  The results show that the minimum inhibitory concentration (MIC) of Ocimum gratissimum essential oil is 2.5μl/ml. Regarding the essential oils of Cymbopogon citractus and Eucalyptus globulus they have a complete inhibition at 0.3μl / ml which is the most concentration tested.  Ethanolic and dichloromethane extracts from different plants showed relative growth of about 77.54% for trunk bark and 41.7% for root bark of Anogeisus leiocarpus. The DCM extract of Momordica charantia showed an inhibition of approximately 59.675% at 800μg/ml.  The essential oils Cymbopogon citractus, Eucalyptus globulus, Ocimum gratissimum and trunk bark of Anogeissus leiocarpus show promise as an antifungal agent.