Neuroprotective effect of pentosan polysulphate on ischemia-related neuronal death of the hippocampus

Pentosan Polysulfate Treatment of Mucopolysaccharidosis Type IIIA Mice

Overall Goal: This study was designed to evaluate the impact of pentosan polysulfate (PPS) treatment on mice with mucopolysaccharidosis (MPS) type IIIA (Sanfilippo A syndrome; OMIM 252900). Protocol: Three groups of MPS IIIA mice were evaluated: 1-week-old mice treated with subcutaneous (subQ) PPS at 25 mg/kg once weekly for 31 weeks (group 1); 5-month-old mice treated with subQ PPS once weekly at 50 mg/kg for 12 weeks (group 2); and 5-week-old mice treated by continual intracerebroventricular (ICV) PPS infusion for 11 weeks (60 μg/kg/day). Treated MPS IIIA mice and controls were assessed by measuring plasma cytokine levels, histologic analyses of systemic organs, and analyses of various neuroinflammatory, neurodegenerative, and lysosomal disease markers in their brains. Neurobehavioral testing also was carried out. Results: As seen in other MPS animal models, subQ PPS treatment reduced plasma cytokine levels and macrophage infiltration in systemic tissues. ICV administration did not elicit these systemic effects. SubQ PPS administration also significantly impacted brain neuropathology, inflammation, and behavior. The effect of early subQ treatment was more significant than dose. Surprisingly, ICV PPS treatment had intermediate effects on most of these brain markers, perhaps due to the limited dose and/or duration of treatment. Consistent with these neuropathological findings, we also observed significant improvements in the hyperactivity/anxiety and learning behaviors of the MPS IIIA mice treated with early subQ PPS.

Anticonvulsant and neuroprotective effects of apelin-13 on pentylenetetrazole-induced seizures in male rats

Epilepsy is a common neurological disorder with no effective treatment or cure. Neuropeptide apelin is an endogenous ligand of angiotensin receptor-like 1 (APJ). It has been shown that apelin has protective and anti-neurodegenerative properties. This study was designed to evaluate the effect of apelin-13 on pentylenetetrazole (PTZ)-induced rat model of seizure. Adult male Wistar rats were divided into the experimental groups as follows: control group receiving PTZ; apelin-treated group which received apelin-13 before PTZ; apelin+F13A-treated group which received apelin-13 plus the apelin receptor antagonist (F13A) before PTZ; apelin+naloxone group which received apelin-13+naloxone before PTZ. Behavioral scoring was used to access seizure. The expression level of APJ was measured by western blotting. Neuronal degeneration, apoptosis and astrocyte activation were evaluated by vanadium acid fuchsin (VAF) staining and immunohistochemistry. Our data demonstrated that apelin-13 pretreatment significantly inhibited seizure threshold (p<0.001) and tonic-clonic latency (p<0.001) compared with the control group. In addition, PTZ-induced up-regulation of APJ was attenuated by apelin-13 treatment. Histological and immunohistochemical findings also showed that apelin-13 could protect cortical neurons against PTZ-induced neuroinflammation and apoptosis. In conclusion, apelin-13 has anticonvulsive and neuroprotective properties against PTZ-induced seizure in rats and provided a new pharmacological aspect of the neuropeptide apelin.

Platelet C4d Is Associated With Acute Ischemic Stroke and Stroke Severity

Background and Purpose— Platelets bearing complement C4d were recently reported to be 99% specific for a diagnosis of systemic lupus erythematosus (SLE) and associated with neuropsychiatric lupus. We compared the prevalence of platelet C4d and investigated the clinical associations of platelet C4d in patients with acute ischemic stroke.

Methods— We recruited 80 patients hospitalized for acute ischemic stroke. Stroke severity was measured by the National Institutes of Health Stroke Scale (NIH-SS). Infarct volume was determined by MRI. Platelet C4d was measured by flow cytometry.

Results— Mean age was 57.9 years (range: 24.6 to 86.8 years), 58% were male, and 91% were white. Eight patients (10%) with acute ischemic stroke were platelet C4d-positive, which was significantly higher in prevalence compared to healthy controls (0%, P <0.0001) and non-SLE patients with immune/inflammatory disease (2%, P =0.004). The median NIH-SS score and infarct volume for acute stroke patients were 6 (interquartile range [IQR]: 2 to 13) and 3.4 cc (IQR: 1.1 to 16.6), respectively. Platelet C4d-positive patients were more likely to have a severe stroke compared to those with negative platelet C4d (NIH-SS median: 17.5 versus 5, P =0.003). Positive platelet C4d was independently associated with stroke severity ( P =0.03) after controlling for age, anticardiolipin antibody (aCL) status, and total anterior circulation of stroke involvement, and also with infarct volume ( P =0.005) after controlling for age, aCL status, and old stroke by MRI.

Conclusions— Platelet C4d is associated with severe acute ischemic stroke. Platelet C4d may be a biomarker as well as pathogenic clue that links cerebrovascular inflammation and thrombosis.