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Biology subjects

Marcon, S.

Publications and source records attributed to Marcon, S..

2 recordsLinked to original sources

First identification of camel prion disease in Tataouine, Tunisia: an emerging animal prion disease in North Africa

Prion diseases are fatal neurodegenerative disorders affecting humans and animals. Among these, camel prion disease (CPrD) was recently identified in Algeria as a novel disease. In this study, we report six CPrD cases in dromedary camels (Camelus dromedarius) from Tunisia, providing further evidence of its occurrence in North Africa. Affected animals exhibited neurological signs and showed PrPSc accumulation in both brain and lymphoid tissues. Molecular and pathological analyses revealed features consistent with Algerian CPrD cases and distinct from classical scrapie and bovine spongiform encephalopathy. The detection of PrPSc in lymphoid organs, together with the relatively young age of some affected individuals, suggests the possibility of a contagious etiology, including potential vertical or early-life transmission mechanisms, as observed in scrapie and chronic wasting disease affecting small ruminants and cervids, respectively. These findings underscore the need for continued surveillance and further investigation into the epidemiology, transmission mechanisms and potential public health implications of CPrD.

microbiology↗

Inactivation of NMDAR and CaMKII signaling within the prelimbic cortex blocks incubated cocaine- and sucrose-craving

The incubation of craving is a term coined to characterize the behavioral phenomenon wherein cue-elicited craving strengthens over a period of abstinence. Incubated cocaine-craving is mediated, at least in part, by increased glutamate release within the prelimbic cortex (PL). We hypothesized that this glutamate release stimulates NMDA-type glutamate receptors (NMDARs) leading to calcium-dependent activation of CaMKII signaling that drives incubated craving. To test this hypothesis, adult male and female Sprague-Dawley rats were trained to self-administer either IV cocaine or sucrose pellets (6h/day x10 days) and tested for cue-elicited cocaine- or sucrose-craving in early versus later (i.e. after incubation) withdrawal. Incubated cocaine-seeking was associated with increased CaMKII activity in the PL, but no change in NMDAR subunits. In contrast, incubated sucrose-craving was associated with many sex-dependent changes in both NMDAR subunit expression and CaMKII activation that were subregion-selective. An intra-PL infusion of the NMDA antagonist D-AP5 (2.5 or 7.5 {micro}g/side) or the CaMKII inhibitor myr-AIP (10 pg/side) blocked both incubated cocaine- and sucrose-craving, with no effects detected in early withdrawal. Co-infusion of both D-AP5 and myr-AIP exerted an additive effect on incubated cocaine-craving that was larger than either antagonist alone. These data corroborate earlier evidence for distinct biochemical correlates within mPFC between incubated cocaine- and sucrose-craving and, for the first time, demonstrate that NMDARs and CaMKII activation within the PL are common drivers of incubated craving that operate via independent signaling pathways suggesting combined pharmacological treatments may have greater efficacy in managing addiction.

neuroscience↗