The development of a validated primate model of progressive parkinsonism is a critical step in the evaluation of drugs that might halt or slow progression of Parkinson's disease. In this pilot study, we gradually exposed 14 cynomolgus monkeys to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), at a weekly dose of 0.5 mg/kg s.c. for 10 weeks, to determine their probability of not reaching a predetermined endpoint on a disability scale by Kaplan-Meier analysis. Four other MPTP-exposed animals were coadministered the potent free radical scavenger 7-hydroxy-1-[4-(3-methoxyphenyl)-1-piperazinyl]acetylamino-2,2,4,6- tetramethylindan (OPC-14117) as a single oral daily dose of 0.6 g/kg, starting 2 weeks before MPTP initiation. The risk of reaching endpoint by week 10 was 79% and mean time before reaching endpoint was 6 weeks. Global motor activity, recorded in a subset of animals using a portable activity monitor, declined following the first MPTP dose and never recovered. Several cerebrospinal fluid indices of central monoamine metabolism collected by suboccipital puncture at 0, 5, and 10 weeks, including HVA, DOPAC, and tetrahydrobiopterin but not MHPG, were found to be "trait" markers for MPTP exposure, whereas CSF DOPAC and tetrahydrobiopterin constituted potential "state" markers for reaching endpoint. The antioxidant OPC-14117 did not protect against MPTP-induced parkinsonism. Further attempts to validate this incremental model of neurotoxin-induced parkinsonism as a predictor of patient responses to putative neuroprotective agents appear warranted.

Download full-text PDF

Source
http://dx.doi.org/10.1006/exnr.1998.6906DOI Listing

Publication Analysis

Top Keywords

reaching endpoint
12
primate model
8
model progressive
8
progressive parkinsonism
8
pilot study
8
free radical
8
radical scavenger
8
dopac tetrahydrobiopterin
8
mptp
5
chronic exposure
4

Similar Publications

Purpose: This phase II study is designed to evaluate the combination therapy involving suvemcitug and envafolimab with FOLFIRI in microsatellite-stable or mismatch repair-proficient (MSS/pMMR) colorectal cancer (CRC) in the second-line treatment setting.

Methods: This study is a non-randomized, open-label prospective study comprising multiple cohorts (NCT05148195). Here, we only report the data from the CRC cohort.

View Article and Find Full Text PDF

Background: In the DISCOMS (DISCOntinuation of disease-modifying therapies (DMTs) in multiple sclerosis (MS)) randomized clinical trial, we could not demonstrate that discontinuing MS DMTs in older, stable adults was not inferior to continuing DMTs. Relapses were rare in both groups, and most new disease activity was one to two new brain magnetic resonance imaging (MRI) lesions unassociated with clinical changes.

Objective/aims: Describe results of the DISCOMS extension study.

View Article and Find Full Text PDF

Background: IgA nephropathy (IgAN) exhibits an unpredictable trajectory, creating difficulties in prognostication, monitoring, treatment, and research planning. This study provides a comprehensive depiction of the progression of kidney function throughout the disease course, from diagnosis to a span of 36 years post-diagnosis.

Methods: We utilized a cohort of 400 Norwegian IgAN patients, from diagnosis to the occurrence of death, initiation of kidney replacement therapy (KRT), or the latest follow-up.

View Article and Find Full Text PDF

Osimertinib as a neoadjuvant therapy in resectable EGFR-mutant non-small cell lung cancer: a real-world, multicenter retrospective study.

Transl Lung Cancer Res

December 2024

Department of Thoracic Surgery, Sichuan Clinical Research Center for Cancer, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, Affiliated Cancer Hospital of University of Electronic Science and Technology of China (UESTC), Chengdu, China.

Background: Osimertinib, a third-generation tyrosine kinase inhibitor (TKI), has been authorized for use in patients with epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC). This study aimed to evaluate the effectiveness and safety of neoadjuvant osimertinib in individuals with resectable locally advanced NSCLC harboring EGFR mutation.

Methods: Ten centers located in mainland China took part in a single-arm, real-world, multicenter retrospective study (registration number: ChiCTR2100049954).

View Article and Find Full Text PDF

Radiotherapy for oligoprogressive disease in non-small cell lung cancer treated with pembrolizumab in first-line setting: a retrospective study.

Transl Lung Cancer Res

December 2024

Department of Medical Oncology, Assistance Publique - Hôpitaux de Paris (AP-HP), Pitié-Salpêtrière Hospital, Institut Universitaire de Cancérologie, CLIP² Galilée, Paris, France.

Background: Oligoprogression (OP) is common in patients with metastatic non-small cell lung cancer (mNSCLC) treated with immune checkpoint inhibitors (ICIs). This study aims to assess the benefit and the safety profile of ablative radiotherapy (RT) for OP in mNSCLC treated with pembrolizumab in first-line setting.

Methods: We retrospectively analyzed records of all consecutive mNSCLC patients who underwent treatment with pembrolizumab (+/- chemotherapy) in first-line setting and developed an OP treated with ablative RT while continuing pembrolizumab, in a French Hospital from 2019 to 2022.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!