ObjectiveWhether activation or inhibition of the mTOR pathway is beneficial to ischemic injury remains controversial. It may result from the different reaction of ischemic penumbra and core to modulation of mTOR pathway after cerebral ischemia–reperfusion injury in rats.MethodsLonga's middle cerebral artery occlusion (MCAO) method was conducted to induce the focal cerebral ischemia–reperfusion. Western blot analysis was used to examine the protein expression involving mTOR pathway, apoptosis, and autophagy‐related proteins. TTC staining and Fluoro‐Jade B staining was conducted to detect the infarct volume and cell apoptosis, respectively. Neurological function was measured by modified neurological severity score and left‐biased swing.Results mTOR signaling pathway was activated in ischemic penumbra and decreased in ischemic core after ischemia and ischemia–reperfusion. Ischemia–reperfusion injury induced the increase in cleaved caspase 9 and caspase 3 both in ischemic penumbra and in ischemic core, whereas the expression of phosphorylated ULK1, Beclin 1 and LC3‐II was decreased. Rapamycin pre or postadministration inhibited the overactivation of mTOR pathway in ischemic penumbra. Ameliorated neurological function and reduced infarct volume were observed after pre or postrapamycin treatment. Rapamycin markedly decreased the number of FJB‐positive cells and the expression of cleaved caspase‐3 and cleaved caspase‐9 proteins as well as increased the activation of autophagy reflected by ULK1, Beclin‐1 and LC3.Interpretation mTOR signaling pathway was activated in ischemic penumbra after cerebral ischemia–reperfusion injury in rats. mTOR inhibitor rapamycin significantly decreased the mTOR activation and infarct volume and subsequently improved neurological function. These results may relate to inhibition of neuron apoptosis and activation of autophagy.

Accumulating data have revealed that abnormal activity of the mTOR (mammalian target of rapamycin) pathway plays an important role in epileptogenesis triggered by various factors. We previously reported that pretreatment with perifosine, an inhibitor of Akt (also called protein kinase B), abolishes the rapamycin-induced paradoxical increase of S6 phosphorylation in a rat model induced by kainic acid (KA). Since Akt is an upstream target in the mTOR signaling pathway, we set out to determine whether perifosine has a preventive effect on epileptogenesis. Here, we explored the effect of perifosine on the model of temporal epilepsy induced by KA in rats and found that pretreatment with perifosine had no effect on the severity or duration of the KA-induced status epilepticus. However, perifosine almost completely inhibited the activation of p-Akt and p-S6 both acutely and chronically following the KA-induced status epilepticus. Perifosine pretreatment suppressed the KA-induced neuronal death and mossy fiber sprouting. The frequency of spontaneous seizures was markedly decreased in rats pretreated with perifosine. Accordingly, rats pretreated with perifosine showed mild impairment in cognitive functions. Collectively, this study provides novel evidence in a KA seizure model that perifosine may be a potential drug for use in anti-epileptogenic therapy.

Loss of the Rptor gene in mice neural progenitor cells affects normal development in young age and may contribute to alleviate KA seizure-induced behavioral abnormalities, suggesting that raptor protein plays an important role in seizure comorbidities.

Aims This clinical study was conducted to evaluate the impact of rifampicin on the pharmacokinetics of fuzuloparib. Methods In this single‐centre, single‐arm, open‐label, fixed‐sequence study, healthy male subjects took a single 50 mg dose of fuzuloparib on two separate occasions: the first was on Day 1 as monotherapy, and the second was on Day 12 after oral administration of rifampicin 600 mg once daily for 8 days. Series of blood samples were obtained before and after fuzuloparib administration at different time points: pre‐dose, and 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 24, 36, 48 and 72 hours post‐dose. All samples were examined using liquid chromatography with tandem mass spectrometry. PK parameters were estimated by using a non‐compartmental method with Phoenix WinNonlin software. Safety was assessed by monitoring for changes in vital signs and laboratory tests, physical examinations, and incidences of adverse events (AEs). Results A total of 16 Chinese male subjects were enrolled. Of these, 16 and 15 cases were evaluable for PK analysis following administration with fuzuloparib alone and pretreatment with rifampicin, respectively. Pretreatment with rifampicin resulted in a statistically significant reduction in the systemic exposure to fuzuloparib. The treatment ratio and 90% confidence intervals (CIs) for AUC0‐∞ and Cmax were 0.10 (0.095–0.115) and 0.32 (0.281–0.365), respectively. A single administration of fuzuloparib after multiple oral dosing of rifampicin was well‐tolerated, without severe AEs. Conclusion The exposure of fuzuloparib was dramatically decreased when pretreated with rifampicin. Strong CYP3A4 inducers should be avoided during fuzuloparib treatment.

Previous studies have demonstrated that rapamycin prevents seizure-induced anxiety-like behaviors. However, rapamycin had been used at a higher dose of 3mg/kg and resulted in side effects in immature animals. The present work was designed to explore whether a lower dose of rapamycin has similar efficacy but has milder side effects. Acute seizures were induced by injection of pilocarpine at postnatal 10 day Sprague-Dawley rats. Western blot analysis was used to detect changes in mTOR pathway after seizure. Immunofluorescent intensity of doublecortin (DCX) was conducted to evaluate the development of neurons in hippocampus. Morris water maze and Y-maze test were used to assess cognitive functions, and open-field test and elevated plus maze were used to detect anxiety-like behaviors 4w after seizure onset. We found that mTOR pathway was abnormally activated with 2 peaks after pilocarpine-induced seizures, and no difference of DCX-positive cells and body weight were noticed between control and pilocarpine-induced seizure rats. Pilocarpine-induced seizure in postnatal 10 d rats did not exert impairment on cognitive functions, but resulted in obvious anxiety-like behaviors. Low dose of rapamycin at 0.3 mg/kg significantly reversed seizure-induced increase of p-S6 levels as well as abnormal anxiety-like behaviors. In addition, rapamycin at the dose of 0.3 mg/kg did not affect normal development and cognitive functions. Therefore, lower doses of rapamycin should be used in infants compared with older children or adults.