No abstract

ABSTRACT:To test the neuroprotective effects of the nonpsychoactive cannabinoid cannabidiol (CBD), piglets received i.v. CBD or vehicle after hypoxia-ischemia (HI: temporary occlusion of both carotid arteries plus hypoxia). Nonhypoxic-ischemic sham-operated piglets remained as controls. Brain damage was studied by near-infrared spectroscopy (NIRS) and amplitudeintegrated electroencephalography (aEEG) and by histologic assessment (Nissl and FluoroJadeB staining). In HIϩvehicle, HI led to severe cerebral hemodynamic and metabolic impairment, as reflected in NIRS by an increase in total Hb index (THI) and a decrease in the fractional tissue oxygenation extraction (FTOE); in HIϩCBD the increase of THI was blunted and FTOE remained similar to SHAM. HI profoundly decreased EEG amplitude, which was not recovered in HIϩvehicle, indicating cerebral hypofunction; seizures were observed in all HIϩvehicle. In HIϩCBD, however, EEG amplitude recovered to 46.4 Ϯ 7.8% baseline and seizures appeared only in 4/8 piglets (both p Ͻ 0.05). The number of viable neurons decreased and that of degenerating neurons increased in HIϩvehicle; CBD reduced both effects by more than 50%. CBD administration was free from side effects; moreover, CBD administration was associated with cardiac, hemodynamic, and ventilatory beneficial effects. In conclusion, administration of CBD after HI reduced short-term brain damage and was associated with extracerebral benefits. (Pediatr Res 64: 653-658, 2008)

Newborn piglets exposed to acute hypoxia-ischemia (HI) received i.v. cannabidiol (HI ϩ CBD) or vehicle (HI ϩ VEH). In HI ϩ VEH, 72 h post-HI brain activity as assessed by amplitudeintegrated EEG (aEEG) had only recovered to 42 Ϯ 9% of baseline, near-infrared spectroscopy (NIRS) parameters remained lower than normal, and neurobehavioral performance was abnormal (27.8 Ϯ 2.3 points, normal 36). In the brain, there were fewer normal and more pyknotic neurons, while astrocytes were less numerous and swollen. Cerebrospinal fluid concentration of neuronal-specific enolase (NSE) and S100␤ protein and brain tissue percentage of TNF␣(ϩ) cells were all higher. In contrast, in HI ϩ CBD, aEEG had recovered to 86 Ϯ 5%, NIRS parameters increased, and the neurobehavioral score normalized (34.3 Ϯ 1.4 points). HI induced histological changes, and NSE and S100␤ concentration and TNF␣(ϩ) cell increases were suppressed by CBD. In conclusion, post-HI administration of CBD protects neurons and astrocytes, leading to histological, functional, biochemical, and neurobehavioral improvements.

Hypothermia is a standard treatment for neonatal encephalopathy, but nearly 50% of treated infants have adverse outcomes. Pharmacological therapies can act through complementary mechanisms with hypothermia improving neuroprotection. Cannabidiol could be a good candidate. Our aim was to test whether immediate treatment with cannabidiol and hypothermia act through complementary brain pathways in hypoxic-ischemic newborn piglets. Hypoxic-ischemic animals were randomly divided into four groups receiving 30 min after the insult: (1) normothermia and vehicle administration; (2) normothermia and cannabidiol administration; (3) hypothermia and vehicle administration; and (4) hypothermia and cannabidiol administration. Six hours after treatment, brains were processed to quantify the number of damaged neurons by Nissl staining. Proton nuclear magnetic resonance spectra were obtained and analyzed for lactate, N-acetyl-aspartate and glutamate. Metabolite ratios were calculated to assess neuronal damage (lactate/N-acetyl-aspartate) and excitotoxicity (glutamate/Nacetyl-aspartate). Western blot studies were performed to quantify protein nitrosylation (oxidative stress), content of caspase-3 (apoptosis) and TNFα (inflammation). Individually, the hypothermia and the cannabidiol treatments reduced the glutamate/Nacetyl-aspartate ratio, as well as TNFα and oxidized protein levels in newborn piglets subjected to hypoxic-ischemic insult. Also, both therapies reduced the number of necrotic neurons and prevented an increase in lactate/N-acetyl-aspartate ratio. The combined effect of hypothermia and cannabidiol on excitotoxicity, inflammation and oxidative stress, and on cell damage, was greater than either hypothermia or cannabidiol alone. The present study demonstrated that cannabidiol and hypothermia act complementarily and show additive effects on the main factors leading to hypoxic-ischemic brain damage if applied shortly after the insult.

Jet aerosolization of perfluorocarbons or surfactant with the intratracheal inhalation catheters seems to be a suitable method for treating experimental respiratory distress syndrome, because it delivers relatively high doses of perfluorocarbons and surfactant to the lungs in a respirable size droplets.

BackgroundBrain hypoxic-ischemic (HI) damage induces distant inflammatory lung damage in newborn pigs. We aimed to investigate the effects of cannabidiol (CBD) on lung damage in this scenario.MethodsNewborn piglets received intravenous vehicle, CBD, or CBD+WAY100635 (5-HT receptor antagonist) after HI brain damage (carotid flow interruption and FiO 0.10 for 30 min). Total lung compliance (TLC), oxygenation index (OI), and extravascular lung water content (EVLW) were monitored for 6 h. Histological damage, interleukin (IL)-1β concentration, and oxidative stress were assessed in brain and lung tissue. Total protein content was determined in bronchoalveolar lavage fluid (BALF).ResultsCBD prevented HI-induced deleterious effects on TLC and OI and reduced lung histological damage, modulating inflammation (decreased leukocyte infiltration and IL-1 concentration) and reducing protein content in BALF and EVLW. These effects were related to CBD-induced anti-inflammatory changes in the brain. HI did not increase oxidative stress in the lungs. In the lungs, WAY100635 blunted the beneficial effects of CBD on histological damage, IL-1 concentration, and EVLW.ConclusionsCBD reduced brain HI-induced distant lung damage, with 5-HT receptor involvement in these effects. Whether the effects of CBD on the lungs were due to the anti-inflammatory effects on the brain or due to the direct effects on the lungs remains to be elucidated.

This study presents the combination of Raman spectroscopy with machine learning algorithms as a prospective diagnostic tool capable of detecting and monitoring relevant variations of pH and lactate as recognized biomarkers of several pathologies. The applicability of the method proposed here is tested both in vitro and ex vivo. In a first step, Raman spectra of aqueous solutions are evaluated for the identification of characteristic patterns resulting from changes in pH or in the concentration of lactate. The method is further validated with blood and plasma samples. Principal component analysis is used to highlight the relevant features that differentiate the Raman spectra regarding their pH and concentration of lactate. Partial least squares regression models are developed to capture and model the spectral variability of the Raman spectra. The performance of these predictive regression models is demonstrated by clinically accurate predictions of pH and lactate from unknown samples in the physiologically relevant range. These results prove the potential of our method to develop a noninvasive technology, based on Raman spectroscopy, for continuous monitoring of pH and lactate in vivo.

BACKGROUND: Newborn pigs offer theoretical advantages for studying newborn hypoxic-ischemic (HI) brain damage because of a development and structure similar to the human brain. However, the correlation between functional features and actual HI brain damage has not been reported. METHODS: Newborn pigs were examined daily for 3 days after a HI insult using amplitude-integrated EEG (aEEG), and a neurobehavioral score enriched with stress and social and object interaction-driven activity evaluation. Brain damage was then assessed using histologic, immunohistochemical, and proton magnetic resonance spectroscopy studies. Brain concentration of several neurotransmitters was determined by HPLC. RESULTS: HI insult led to aEEG amplitude decrease, muscle tone and activity impairment, eating disorders, poor environmental interaction, and increased motionless periods. Basal aEEG amplitude, muscle tone, and general behavior were the best predictive items for histological and biochemical (lactate/N-acetylaspartate ratio) brain damage. Hyperexcitable response to stress correlated inversely with brain damage. Motionless time, which correlated with brain damage severity, was inversely related to brain concentration of dopamine and norepinephrine. CONCLUSION: Standard neurologic examination of brain activity and motor and behavioral performance of newborn pigs is a valuable tool to assess HI brain damage, thus offering a powerful translational model for HI brain damage pathophysiology and management studies.