Cognitive impairment and markers of optical neurodegeneration in early multiple sclerosis.

INTRODUCTION: Cognitive impairment and retinal atrophy have been proposed as two potential markers of neurodegeneration in multiple sclerosis (MS). We aimed at assessing the relation between peripapillary retinal nerve fiber layer (pRNFL) and macular ganglion cell layer (mGCL) atrophy and cognitive performance in early MS. METHODS: This is a multicenter cross-sectional study on patients with early MS (clinically isolated syndrome and relapsing-remitting MS), with an EDSS score ≤ 3.0. Patients with previous optic neuritis, other ocular diseases, psychiatric illness, or recent relapse were excluded. All patients underwent standardized optical coherence tomography (OCT) and neuropsychological evaluation with validated tests for MS patients. Cognitive impairment was defined as having two cognitive tasks below age- and education-adjusted norms. RESULTS: We recruited 52 patients with early MS, with an average age of 37 years (SD = 10.5), an average disease duration of 3.69 years (SD = 2.3), and a median EDSS of 1.0 (IQR = 0.5). In this sample, 15/52 patients presented cognitive impairment. Regarding OCT measurements, 7/52 patients had an average pRNFL below the 5th percentile and 2/52 had an average mGCL below the 5th percentile. The average pRNFL thickness was comparable in cognitively impaired and cognitively preserved patients (100.3 µm vs 103.1 µm, p = 0.52); the average mGCL thickness had also similar values between groups (50.5 µm vs 53 µm, p = 0.38). CONCLUSIONS: Cognitive impairment was frequent in our sample of early MS. However, no association with reduced pRNFL or mGCL thickness was found. When compared to OCT, cognitive assessment could provide an earlier marker of neurodegeneration in MS.

Effects of Marapuama in the chronic mild stress model: further indication of antidepressant properties.

ETHNOPHARMACOLOGY RELEVANCE: Ptychopetalum olacoides Bentham (PO) (Olacaceae), known as Marapuama, is regarded as a "nerve tonic" in the Amazon. Traditional uses include states of lassitude with noticeable lack of desire/motivation, and to manage particularly stressful (physical and/or psychological) circumstances. Suggestive of antidepressant activity, we have established that a specific PO ethanol extract (POEE) significantly decreases immobility in the tail suspension and forced swimming tests. AIM OF THE STUDY: The aim of this study was to verify the effects of POEE in the unpredictable chronic mild stress (UCMS) depression model in mice, given the construct and face values of the UCMS as an experimental model of depression and the traditional use of this species. MATERIALS AND METHODS: Over 6 weeks BALB/c mice were subjected to the UCMS protocol. The effects of POEE (50, 100, 300mg/kg, p.o.) and imipramine (20mg/kg, i.p.) were evaluated in relation to coat state, splash-test grooming, and corticosterone levels. RESULTS: The coat state degradation, decreased grooming and increased serum corticosterone induced by UCMS were prevented by POEE and imipramine treatments. CONCLUSION: In addition to supporting traditional claims and previously reported antidepressant properties for POEE, this study shows that POEE prevents stress-induced HPA hyperactivity.