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Del-Bel, E. A.

Publications and source records attributed to Del-Bel, E. A..

2 recordsLinked to original sources

Doxycycline inhibits α-synuclein-associated pathologies in vitro and in vivo

Parkinsons disease (PD) and dementia with Lewy bodies (DLB) are neurodegenerative disorders characterized by the misfolding and aggregation of alpha-synuclein (aSyn). Doxycycline, a tetracyclic antibiotic shows neuroprotective effects, initially proposed to be due to its anti-inflammatory properties. More recently, an additional mechanism by which doxycycline may exert its neuroprotective effects has been proposed as it has been shown that it inhibits amyloid aggregation. Here, we studied the effects of doxycycline on aSyn aggregation in vivo, in vitro and in a cell free system using real-time quaking induced conversion (RT-QuiC). Our results show that doxycycline decreases the number and size of aSyn aggregates in cells. In addition, doxycycline inhibits the aggregation and seeding of recombinant aSyn, and attenuates the production of mitochondrial-derived reactive oxygen species. Finally, we found doxycycline induces a cellular redistribution of the aggregates in an animal model of PD that is associated with a recovery of dopaminergic function. In summary, we provide strong evidence that doxycycline treatment may be an effective strategy against synucleinopathies.

molecular biology

SK3-overexpression drives sex-dimorphic working and social memory impairment in mice.

Although sex differences in memory tasks dependent on hippocampal function have been described in several species, including rodents and humans, the exact mechanisms involved remain debatable. The function of the small-conductance Ca2+-activated K+ channel type 3 has been associated with cognitive deficits, and its overexpression in male mice (T/T) induces shrinkage of the hippocampus. Here we describe that opposite to the observation in males, in female mice, SK3-induced-reduction in the volume of the hippocampal formation does not interfere with working and social memory performance. Male, but not female T/T mice showed decreased adult hippocampal neurogenesis and down-regulation of the expression of the genes related to Akt/mTOR and MAP kinase pathways. T/T male mice exhibit impaired estrogen and Neurogulin 1 signaling. An increased number of filopodia spines is observed in the dentate gyrus (DG). Our results suggest a fine-tune modulation of SK3 expression participates in the sex-dependent function of the hippocampus via estrogen signaling and neuroplasticity in the DG. Our results reinforce the importance of testing male and female mice while conducting experiments with transgenic mice.

neuroscience