Six Weeks of Voluntary Exercise don’t Protect C57BL/6 Mice Against Neurotoxicity of MPTP and MPP+

Exercise improves the central nervous system (CNS) functions and is widely recommended for neurological patients with, e.g., Alzheimer’s and Parkinson’s disease (PD). However, exercise-induced neuroprotection is an open discussion. Here, the intranasal administration of the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 65 mg/kg) caused death of dopaminergic neurons in the substantia nigra pars compacta and depletion of dopamine in the striatum of C57BL/6 mice. 1-Methyl-4-phenylpyridinium, the active metabolite of MPTP, also inhibited complex-I activity of mitochondria isolated from the CNS of mice. However, 6 weeks of exercise on voluntary running wheels did not protect against nigrostriatal neurodegeneration or mitochondrial inhibition, suggesting that benefits of exercise for PD may not be associated with neuroprotection. The literature presents other candidates, such as neurotrophins or increased antioxidant defenses.     

Effect of S-methylisothiourea,an inducible nitric oxide synthase inhibitor,in joint pain and pathology in surgically induced model of osteoarthritis

The aim of the present study was to evaluate in vivo modulatory effect of S-methylisothiourea (SMT), a preferential inhibitor of inducible nitric oxide synthase (iNOS) on pain and pathology in the surgical model of osteoarthritis (OA) in rats. The OA was produced by the anterior cruciate ligament transection (ACLT) and medial meniscectomy (MMx) of right knee. SMT was administered 1 day prior to the production of OA and continued up to day 42 postoperation. Mechanical hyperalgesia, thermal hyperalgesia, tail flick latency after repeated flexion and extension of OA knee and knee diameter of right knee were determined at weekly intervals. Serum levels of IL-1β, TNF-α and nitrite concentration were determined at the end of the experiment. Glycosaminoglycan (GAG) content, collagen content and histopathological evaluation of articular cartilage were also determined at the end of the experiment. SMT reduced mechanical hyperalgesia and the serum levels of IL-1β, TNF-α and nitrite. Further, SMT reduced the loss of GAG from articular cartilage. Microscopically, SMT reduced the severity of the cartilage lesion. The results indicate the effectiveness of SMT in attenuating the pain and pathology of experimental OA phase by reducing the production of nitric oxide and interleukin-1β and tumor necrosis factor-α, which are known to play a major role in the pathophysiology of OA.     

Long-term effectiveness and safety of interleukin-1 receptor antagonist (anakinra) in Schnitzler's syndrome: A french multicenter study

The aim of this study is to assess the long-term effectiveness and safety of IL1Ra in Schnitzler syndrome (SchS). Between 2010 and 2012, we performed a nationwide survey among French internal medicine departments to identify SchS patients. We retrospectively analyzed the long-term efficacy and safety of IL1Ra and the outcome of patients that did not receive this treatment. Forty-two patients were included in the study, 29 of whom received IL1Ra. The mean age at disease onset was 59.9 years. Disease manifestations included urticaria (100%), fever (76%), bone/joint pain (86%), bone lesions (76%), anemia (67%), and weight loss (60%). The monoclonal gammopathy was overwhelmingly IgM kappa (83%). The mean follow-up was 9.5 years (range: 1.6-35). Two patients developed Waldenström's macroglobulinemia and one developed AA amyloidosis. All of the 29 patients who received IL1Ra responded dramatically. After a median follow-up of 36 months (range: 2-79), the effectiveness remained unchanged. All patients remained on anti-IL-1 therapy. Twenty-four patients (83%) went into complete remission and five (17%) into partial remission. Three patients experienced grade 3-4 neutropenia. Six patients developed severe infections. No lymphoproliferative diseases occurred while on IL1Ra. When last seen, all patients without anakinra had an active disease with variable impact on their quality of life. Their median corticosteroids dosage was 6 mg/d (range: 5-25). IL1Ra is effective in SchS, with a sharp corticosteroid-sparing effect. Treatment failures should lead to reconsider the diagnosis. Long-term follow-up revealed no loss of effectiveness and a favorable tolerance profile. The long-term effects on the risk of hemopathy remain unknown.