Pazos, MR et al.Alvarez, Francisco J.Martínez Orgado, José Antonio2025-01-292025-01-292013Pazos MR, Mohammed N, Lafuente H, Santos M, Martínez-Pinilla E, Moreno E, Valdizan E, Romero J, Pazos A, Franco R, Hillard CJ, Alvarez FJ, Martínez-Orgado J. Mechanisms of cannabidiol neuroprotection in hypoxic-ischemic newborn pigs: role of 5HT(1A) and CB2 receptors. Neuropharmacology. 2013 Aug;71:282-91. doi: 10.1016/j.neuropharm.2013.03.027. Epub 2013 Apr 12. PMID: 23587650.10.1016/j.neuropharm.2013.03.027https://hdl.handle.net/20.500.14352/117049The mechanisms underlying the neuroprotective effects of cannabidiol (CBD) were studied in vivo using a hypoxic-ischemic (HI) brain injury model in newborn pigs. One- to two-day-old piglets were exposed to HI for 30 min by interrupting carotid blood flow and reducing the fraction of inspired oxygen to 10%. Thirty minutes after HI, the piglets were treated with vehicle (HV) or 1 mg/kg CBD, alone (HC) or in combination with 1 mg/kg of a CB₂ receptor antagonist (AM630) or a serotonin 5HT(1A) receptor antagonist (WAY100635). HI decreased the number of viable neurons and affected the amplitude-integrated EEG background activity as well as different prognostic proton-magnetic-resonance-spectroscopy (H(±)-MRS)-detectable biomarkers (lactate/N-acetylaspartate and N-acetylaspartate/choline ratios). HI brain damage was also associated with increases in excitotoxicity (increased glutamate/N-acetylaspartate ratio), oxidative stress (decreased glutathione/creatine ratio and increased protein carbonylation) and inflammation (increased brain IL-1 levels). CBD administration after HI prevented all these alterations, although this CBD-mediated neuroprotection was reversed by co-administration of either WAY100635 or AM630, suggesting the involvement of CB₂ and 5HT(1A) receptors. The involvement of CB₂ receptors was not dependent on a CBD-mediated increase in endocannabinoids. Finally, bioluminescence resonance energy transfer studies indicated that CB₂ and 5HT(1A) receptors may form heteromers in living HEK-293T cells. In conclusion, our findings demonstrate that CBD exerts robust neuroprotective effects in vivo in HI piglets, modulating excitotoxicity, oxidative stress and inflammation, and that both CB₂ and 5HT(1A) receptors are implicated in these effects.engAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/journal articlehttps://doi.org/10.1016/j.neuropharm.2013.03.027https://www.sciencedirect.com/science/article/pii/S0028390813001238?via%3Dihubrestricted access61Ciencias Biomédicas24 Ciencias de la Vida