Fructose supplementation shifts rat brain metabolism in experimental migraine.

AIMS: We have previously demonstrated that fructose supplementation (FS), given in a scheme used for inducing metabolic syndrome (MS), elicited pain relief in the nitroglycerin (NTG)-elicited rat migraine model. Herein, we evaluated whether FS could reestablish the impaired metabolic pathways in NTG-injected rats. MAIN METHODS: Male Wistar rats (N = 40) were divided into two groups for receiving 10 % FS or tap water. After 45 days, they were subdivided into NTG-injected (10 mg/kg; 15 days) or controls. After the fourth NTG injection, 18F-fluorodeoxyglucose ([18F] FDG) micro-PET scanning was accomplished. The day after, euthanasia was performed, and blood was collected for glycemia and LDH analysis. The levels of energy molecules, TBARS, PGC-1α, and MCTS1 were evaluated in the brain cortices. The activated satellite glial cells (SGC) were assessed in the trigeminal ganglion (TG). KEY FINDINGS: There were no variations of glycemia or LDH serum levels. NTG-injected rats showed a significant increase in glucose uptake in the hypothalamus (HT) vs. NTG-free rats. The FS-NTG group showed increased metabolism in the superior colliculus (SC) vs. the NTG group. Moreover, the glucose uptake was amplified in the inferior colliculus (IC) of the FS-NTG vs. FS group. The cortical inosine levels were significantly higher in FS-NTG rats vs. NTG or FS groups, with no changes in TBARS or MCTS1 levels, despite a minor decrease of PGC1-α contents in the FS+NTG group. Finally, there was a significant increase of activated SGC around TG in the FS-NTG rats. SIGNIFICANCE: We provide novel evidence linking nutrition and metabolism with migraine.

Beneficial Effects of the Calcium Channel Blocker CTK 01512-2 in a Mouse Model of Multiple Sclerosis.

Voltage-gated calcium channels (VGCCs) play a critical role in neuroinflammatory diseases, such as multiple sclerosis (MS). CTK 01512-2 is a recombinant version of the peptide Phα1ß derived from the spider Phoneutria nigriventer, which inhibits N-type VGCC/TRPA1-mediated calcium influx. We investigated the effects of this molecule in the mouse model of experimental autoimmune encephalomyelitis (EAE). The effects of CTK 01512-2 were compared to those displayed by ziconotide-a selective N-type VGCC blocker clinically used for chronic pain-and fingolimod-a drug employed for MS treatment. The intrathecal (i.t.) treatment with CTK 01512-2 displayed beneficial effects, by preventing nociception, body weight loss, splenomegaly, MS-like clinical and neurological scores, impaired motor coordination, and memory deficits, with an efficacy comparable to that observed for ziconotide and fingolimod. This molecule displayed a favorable profile on EAE-induced neuroinflammatory changes, including inflammatory infiltrate, demyelination, pro-inflammatory cytokine production, glial activation, and glucose metabolism in the brain and spinal cord. The recovery of spatial memory, besides a reduction of serum leptin levels, allied to central and peripheral elevation of the anti-inflammatory cytokine IL-10, was solely modulated by CTK 01512-2, dosed intrathecally. The intravenous (i.v.) administration of CTK 01512-2 also reduced the EAE-elicited MS-like symptoms, similarly to that seen in animals that received fingolimod orally. Ziconotide lacked any significant effect when dosed by i.v. route. Our results indicate that CTK 01512-2 greatly improved the neuroinflammatory responses in a mouse model of MS, with a higher efficacy when compared to ziconotide, pointing out this molecule as a promising adjuvant for MS management.

N-acetylcysteine prevents spatial memory impairment induced by chronic early postnatal glutaric acid and lipopolysaccharide in rat pups.

BACKGROUND AND AIMS: Glutaric aciduria type I (GA-I) is characterized by accumulation of glutaric acid (GA) and neurological symptoms, such as cognitive impairment. Although this disease is related to oxidative stress and inflammation, it is not known whether these processes facilitate the memory impairment. Our objective was to investigate the performance of rat pups chronically injected with GA and lipopolysaccharide (LPS) in spatial memory test, antioxidant defenses, cytokines levels, Na+, K+-ATPase activity, and hippocampal volume. We also evaluated the effect of N-acetylcysteine (NAC) on theses markers. METHODS: Rat pups were injected with GA (5 umol g of body weight-1, subcutaneously; twice per day; from 5th to 28th day of life), and were supplemented with NAC (150 mg/kg/day; intragastric gavage; for the same period). LPS (2 mg/kg; E.coli 055 B5) or vehicle (saline 0.9%) was injected intraperitoneally, once per day, from 25th to 28th day of life. Oxidative stress and inflammatory biomarkers as well as hippocampal volume were assessed. RESULTS: GA caused spatial learning deficit in the Barnes maze and LPS potentiated this effect. GA and LPS increased TNF-α and IL-1ß levels. The co-administration of these compounds potentiated the increase of IL-1ß levels but not TNF-α levels in the hippocampus. GA and LPS increased TBARS (thiobarbituric acid-reactive substance) content, reduced antioxidant defenses and inhibited Na+, K+-ATPase activity. GA and LPS co-administration did not have additive effect on oxidative stress markers and Na+, K+ pump. The hippocampal volume did not change after GA or LPS administration. NAC protected against impairment of spatial learning and increase of cytokines levels. NAC Also protected against inhibition of Na+,K+-ATPase activity and oxidative markers. CONCLUSIONS: These results suggest that inflammatory and oxidative markers may underlie at least in part of the neuropathology of GA-I in this model. Thus, NAC could represent a possible adjuvant therapy in treatment of children with GA-I.

Clozapine, but not typical antipsychotics, correct P50 suppression deficit in patients with schizophrenia.

OBJECTIVE: To find out if there is a difference in P50 suppression between patients using typical antipsychotic drugs and those using clozapine, as well as to confirm the findings of abnormal P50 suppression in patients with schizophrenia, when compared to healthy volunteers. METHODS: Fifty patients with schizophrenia and 25 healthy volunteers were divided into 3 groups: group 1 - patients using typical antipsychotics; group 2 - patients using clozapine; group 3 - controls. Before the examination, all patients were interviewed by a psychiatrist using the Brief Psychiatry Rating Scale (BPRS). RESULTS: The average S2/S1 ratio was 0.82+/-0.45 in group 1, 0.57+/-0.41 in group 2, and 0.44+/-0.27 in group 3 (P=0.003). Statistical analysis showed a significant difference when the results of group 1 were compared to those of groups 2 (P=0.045) and 3 (P=0.001). There was no significant difference between groups 2 and 3 (P=0.182). There was a significant difference in the S1-S2 difference only between groups 1 and 3 (P=0.007), but a non-significant trend towards a similar difference was found between groups 1 and 2 (P=0.067). There was no correlation between the BPRS values and any P50 parameter. CONCLUSIONS: The suppression of P50 among patients using clozapine was significantly greater than that obtained in patients using typical antipsychotics. SIGNIFICANCE: This study confirms, in a more evident way, the improvement of the suppression of P50 potential in schizophrenics using clozapine. Additionally, it discusses the physiopathological mechanism involved.