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Nicotinic acetylcholine receptors (nAChRs) are involved in seizure mechanisms. Hence, nocturnal frontal lobe epilepsy was the first idiopathic epilepsy linked with specific mutations in α4 or β2 nAChR subunit genes. These mutations confer gain of function to nAChRs by increasing sensitivity toward acetylcholine. Consistently, nicotine elicits seizures through nAChRs and mimics the excessive nAChR activation observed in animal models of the disease. Treatments aimed at reducing nicotinic inputs are sought as therapies for epilepsies where these receptors contribute to neuronal excitation and synchronization. Previous studies demonstrated that peroxisome proliferator-activated receptors-α (PPARα), nuclear receptor transcription factors, suppress nicotine-induced behavioral and electrophysiological effects by modulating nAChRs containing β2 subunits. On these bases, we tested whether PPARα agonists were protective against nicotine-induced seizures. To this aim we utilized behavioral and electroencephalographic (EEG) experiments in C57BL/J6 mice and in vitro patch clamp recordings from mice and rats. Convulsive doses of nicotine evoked severe seizures and bursts of spike-waves discharges in ∼100% of mice. A single dose of the synthetic PPARα agonist WY14643 (WY, 80 mg/kg, i.p.) or chronic administration of fenofibrate, clinically available for lipid metabolism disorders, in the diet (0.2%) for 14 days significantly reduced or abolished behavioral and EEG expressions of nicotine-induced seizures. Acute WY effects were reverted by the PPARα antagonist MK886 (3 mg/kg, i.p.). Since neocortical networks are crucial in the generation of ictal activity and synchrony, we performed patch clamp recordings of spontaneous inhibitory postsynaptic currents (sIPSCs) from frontal cortex layer II/III pyramidal neurons. We found that both acute and chronic treatment with PPARα agonists abolished nicotine-induced sIPSC increases. PPARα within the CNS are key regulators of neuronal activity through modulation of nAChRs. These effects might be therapeutically exploited for idiopathic or genetically determined forms of epilepsy where nAChRs play a major role.

Summary Aims Prenatal maternal immune activation (MIA) is associated with a risk to develop schizophrenia and affects dopamine systems in the ventral tegmental area (VTA), key region in the neurobiology of psychoses. Considering the well‐described sex differences in schizophrenia, we investigated whether sex affects MIA impact on dopamine system and on schizophrenia‐related behavioral phenotype. Furthermore, considering peroxisome proliferator‐activated receptor‐α (PPARα) expression in the CNS as well as its anti‐inflammatory and neuroprotective properties, we tested if PPARα activation by prenatal treatment with a clinically available fibrate (fenofibrate) may mitigate MIA‐related effects. Methods We induced MIA in rat dams with polyriboinosinic‐polyribocytidylic acid (Poly I:C) and assessed prepulse inhibition and dopamine neuron activity in the VTA by means of electrophysiological recordings in male and female preweaned and adult offspring. Results Poly I:C‐treated males displayed prepulse inhibition deficits, reduced number and firing rate of VTA dopamine neurons, and paired‐pulse facilitation of inhibitory and excitatory synapses. Prenatal fenofibrate administration attenuated detrimental effects induced by MIA on both the schizophrenia‐like behavioral phenotype and dopamine transmission in male offspring. Conclusion Our study confirms previous evidence that females are less susceptible to MIA and highlights PPARα as a potential target for treatments in schizophrenia .

A 'blind' study has been made to try to find out if it is possible to diagnose carriers of haemophilia. A group of 34 obligatory carriers of haemophilia were compared with 34 normal women. Levels of factor VIII activity, factor VIII-related antigen, factor V and ratio of factor VIII activity to factor VIII-related antigen were measured. In the carrier group the mean level of factor VIII activity and the mean level of the ratio of activity to antigen were each approximately half of those found in the normal women. The mean level of factor V was the same in both groups of women. By setting the lower limit of normal at the lowest level of the different factors found in the normal women, 12 out of 34 (35%) carriers could be distinguished on the basis of their factor VIII level alone; 24 out of 34 (71%) could be detected on the basis of the ratio of factor VIII activity to factor VIII related antigen and 25 out of 34 (73%) could be detected if both factor VIII activity and the ratio were taken into account. It is concluded that consideration of both the level of factor VIII activity and the ratio of factor VIII activity to factor VIII-related antigen is of some value in detecting carriers of haemophilia. The number of carriers detected (73%) in the present study is not as high as that found by other workers.

Our preclinical and clinical studies suggest PPARα as a novel disease-modifying target for antiepileptic drugs due to its ability to regulate dysfunctional nAChRs.

This study, while confirming the reinforcing effects of MXE, highlights an electrophysiological and neurochemical profile predictive of its addictive properties.