Fraternine, a Novel Wasp Peptide, Protects against Motor Impairments in 6-OHDA Model of Parkinsonism.

Parkinson's disease (PD) is a progressive neurodegenerative condition that affects the Central Nervous System (CNS). Insect venoms show high molecular variability and selectivity in the CNS of mammals and present potential for the development of new drugs for the treatment of PD. In this study, we isolated and identified a component of the venom of the social wasp Parachartergus fraternus and evaluated its neuroprotective activity in the murine model of PD. For this purpose, the venom was filtered and separated through HPLC; fractions were analyzed through mass spectrometry and the active fraction was identified as a novel peptide, called Fraternine. We performed two behavioral tests to evaluate motor discoordination, as well as an apomorphine-induced rotation test. We also conducted an immunohistochemical assay to assess protection in TH+ neurons in the Substantia Nigra (SN) region. Group treated with 10 µg/animal of Fraternine remained longer in the rotarod compared to the lesioned group. In the apomorphine test, Fraternine decreased the number of rotations between treatments. This dose also inhibited dopaminergic neuronal loss, as indicated by immunohistochemical analysis. This study identified a novel peptide able to prevent the death of dopaminergic neurons of the SN and recover motor deficit in a 6-OHDA-induced murine model of PD.

Effects of the hallucinogenic beverage ayahuasca on voluntary ethanol intake by rats and on cFos expression in brain areas relevant to drug addiction.

Ayahuasca is a hallucinogenic infusion used in religious rituals that has serotoninergic properties and may be a potential therapeutic option for drug addiction. In this study, Wistar rats had intermittent access to ethanol for 8 weeks, receiving water (control), naltrexone (NTX, 2 mg/kg body weight [bw] intraperitoneally [i.p.]) or ayahuasca (Aya) at 0.5x, 1x, or 2x the ritual dose in the final 5 days. A naïve group had access only to water. Ethanol intake was estimated throughout the experiment, and cFos expression was evaluated in medial orbital cortex (MO), ventral orbital cortex (VO), lateral orbital cortex (LO), nucleus accumbens (NAc), and striatum. Treatment with either NTX or Aya (oral) did not decrease ethanol intake compared to the baseline level (5th to 7th week), but the NTX group intake was significantly lower than controls (p < 0.05). Ethanol significantly increased cFos expression in the MO region for control (p < 0.0001), NTX (p < 0.05), Aya1 (p < 0.001), and Aya2 (p < 0.0001) groups. This increase was also observed in the VO for the Aya1 group (p = 0.035), in the LO for the Aya2 group (p < 0.01), and in NAc for NTX and ayahuasca groups (p < 0.005). Furthermore, NTX and Aya0.5 treatment decreased cFos expression compared to controls in the MO region (p < 0.05 and p < 0.01, respectively), but only the ayahuasca group reached levels not significantly different from the naïve group. Studies using other protocols and dose regime are necessary to better investigate the impact of ayahuasca on alcohol intake by rats to support the observations in humans. Additionally, the role of ayahuasca in mediating cFos expression in other selected brain regions and its relationship with the serotoninergic/dopaminergic systems and drug addiction need further investigation.