Skeletal Muscle NADPH Oxidase Is Increased and Triggers Stretch-Induced Damage in the mdx Mouse

Recent studies have shown that oxidative stress contributes to the pathogenesis of muscle damage in dystrophic (mdx) mice. In this study we have investigated the role of NADPH oxidase as a source of the oxidative stress in these mice. The NADPH oxidase subunits gp91phox, p67phox and rac 1 were increased 2–3 fold in tibilais anterior muscles from mdx mice compared to wild type. Importantly, this increase occurred in 19 day old mice, before the onset of muscle necrosis and inflammation, suggesting that NADPH oxidase is an important source of oxidative stress in mdx muscle. In muscles from 9 week old mdx mice, gp91phox and p67phox were increased 3–4 fold and NADPH oxidase superoxide production was 2 times greater than wild type. In single fibers from mdx muscle NADPH oxidase subunits were all located on or near the sarcolemma, except for p67phox,which was expressed in the cytosol. Pharmacological inhibition of NADPH oxidase significantly reduced the intracellular Ca2+ rise following stretched contractions in mdx single fibers, and also attenuated the loss of muscle force. These results suggest that NADPH oxidase is a major source of reactive oxygen species in dystrophic muscle and its enhanced activity has a stimulatory effect on stretch-induced Ca2+ entry, a key mechanism for muscle damage and functional impairment

Functional cyclophilin D moderates platelet adhesion, but enhances the lytic resistance of fibrin

In the course of thrombosis, platelets are exposed to a variety of activating stimuli classified as ‘strong’ (e.g. thrombin and collagen) or ‘mild’ (e.g. ADP). In response, activated platelets adhere to injured vasculature, aggregate, and stabilise the three-dimensional fibrin scaffold of the expanding thrombus. Since ‘strong’ stimuli also induce opening of the mitochondrial permeability transition pore (MPTP) in platelets, the MPTP-enhancer Cyclophilin D (CypD) has been suggested as a critical pharmacological target to influence thrombosis. However, it is poorly understood what role CypD plays in the platelet response to ‘mild’ stimuli which act independently of MPTP. Furthermore, it is unknown how CypD influences platelet-driven clot stabilisation against enzymatic breakdown (fibrinolysis). Here we show that treatment of human platelets with Cyclosporine A (a cyclophilin-inhibitor) boosts ADP-induced adhesion and aggregation, while genetic ablation of CypD in murine platelets enhances adhesion but not aggregation. We also report that platelets lacking CypD preserve their integrity in a fibrin environment, and lose their ability to render clots resistant against fibrinolysis. Our results indicate that CypD has opposing haemostatic roles depending on the stimulus and stage of platelet activation, warranting a careful design of any antithrombotic strategy targeting CypD

Visuoconstructive abilities and visuospatial memory in autism spectrum disorder without intellectual disability: Is the role of local bias specific to the cognitive domain tested?

Objective: Visuospatial processing in autism spectrum disorder (ASD) without intellectual disability remains only partly understood. The aim of the present study was to investigate global versus local visuospatial processing in individuals with ASD, comparing them with typically developing (TD) controls in visuoconstructive and visuospatial memory tasks. Method: There were 21 participants with ASD without intellectual disability, and 21 TD controls matched for chronological age (M 161.37 months, SD 38.19), gender, and perceptual reasoning index who were tested. Participants were administered tasks assessing the visuoconstructive domain and involving fine motor skills, and visuospatial memory tasks in which visuospatial information had to be manipulated mentally. Results: Using a mixed-effects model approach, our results showed different effects of local bias in the ASD group, depending on the domain considered: the use of a local approach only emerged for the visuoconstructive domain\u2014in which fine motor skills were involved. Conclusions: These results seem to suggest that the local bias typical of the cognitive profile of ASD without intellectual disability could be a property of specific cognitive domains rather than a central mechanism

MICU1 Serves as a Molecular Gatekeeper to Prevent In Vivo Mitochondrial Calcium Overload

MICU1 is a component of the mitochondrial calcium uniporter, a multiprotein complex that also includes MICU2, MCU, and EMRE. Here, we describe a mouse model of MICU1 deficiency. MICU1−/− mitochondria demonstrate altered calcium uptake, and deletion of MICU1 results in significant, but not complete, perinatal mortality. Similar to afflicted patients, viable MICU1−/− mice manifest marked ataxia and muscle weakness. Early in life, these animals display a range of biochemical abnormalities, including increased resting mitochondrial calcium levels, altered mitochondrial morphology, and reduced ATP. Older MICU1−/− mice show marked, spontaneous improvement coincident with improved mitochondrial calcium handling and an age-dependent reduction in EMRE expression. Remarkably, deleting one allele of EMRE helps normalize calcium uptake while simultaneously rescuing the high perinatal mortality observed in young MICU1−/− mice. Together, these results demonstrate that MICU1 serves as a molecular gatekeeper preventing calcium overload and suggests that modulating the calcium uniporter could have widespread therapeutic benefits

Nasopharyngeal cancer in non-endemic areas: Impact of treatment intensity within a large retrospective multicentre cohort

60siAim: Recommendations for managing patients with nasopharyngeal carcinoma (NPC) in non-endemic areas are largely derived from studies conducted in endemic areas. We analysed the impact of treatment approaches on survival in non-endemic areas. Methods: In an international, multicentre, retrospective study, we analyse consecutive patients with NPC diagnosed between 2004 and 2017 in 36 hospitals from 11 countries. Treatment was categorised as non-intensive (NIT), including radiotherapy alone or concomitant chemoradiotherapy (cCRT), and intensive (IT) including cCRT preceded by and/or followed by chemotherapy (CT). The impact of IT on overall survival (OS) and disease-free survival (DFS) was adjusted for all the available potential confounders. Results: Overall, 1021 and 1113 patients were eligible for overall survival (OS) and disease-free survival (DFS) analyses, respectively; 501 and 554 with Epstein Barr-encoded RNA (EBER) status available. In the whole group, 5-year OS was 84% and DFS 65%. The use of NIT was associated with a risk of death or recurrence 1.37 times higher than patients receiving IT. Patients submitted to NIT and induction CT + concurrent concomitant chemo and three-dimensional Conformal Radiation Therapy (3DCRT) had a risk of death or recurrence 1.5 and 1.7 times higher than patients treated with induction CT + cCRT with intensity-modulated radiotherapy (IMRT), respectively. The IT had no impact on OS in neither patients with EBER+ nor in patients with EBER-; IT showed better DFS in EBER+ but not in patients with EBER-. Conclusions: In low-incidence areas, patients with NPC treated with induction CT followed by concurrent IMRT cCRT achieved the highest DFS rate. The benefit of IT on DFS was restricted to patients with EBER+, suggesting that additional therapy offers no advantages in EBER- cases.restrictedrestrictedBossi P.; Trama A.; Bernasconi A.; Grisanti S.; Mohamad I.; Galiana I.L.; Ozyar E.; Franco P.; Vecchio S.; Bonomo P.; Cirauqui B.C.; El-Sherify M.; Ursino S.; Argiris A.; Pan J.; Wittekindt C.; D'Angelo E.; Costa L.; Buglione M.; Johnson J.; Airoldi M.; Mesia R.; Resteghini C.; Licitra L.; Orlandi E.; Martin M.; Battaglia P.; Turri-Zanoni M.; Lionello M.; Azzarello G.; Boscolo G.; Moro C.; Maffioletti L.; Iannacone E.; Garassino I.; Baatenburg de Jong R.J.; Hardillo J.; Mastromauro C.; Menazza S.; Secondino S.; Montagnani B.F.; Zustovich F.; Da Corte D.; De Renzi F.; Aprile G.; Pancheri F.; Rossetto C.; Ghiani M.; Carta P.; Dessi A.; Cau M.C.; Ramos S.; Charoula H.; Giannakopoulou E.; Verstraete H.; Nevens D.; Velasco M.; Bonfill T.; Restoy E.M.; Franzetti-Pellanda A.Bossi, P.; Trama, A.; Bernasconi, A.; Grisanti, S.; Mohamad, I.; Galiana, I. L.; Ozyar, E.; Franco, P.; Vecchio, S.; Bonomo, P.; Cirauqui, B. C.; El-Sherify, M.; Ursino, S.; Argiris, A.; Pan, J.; Wittekindt, C.; D'Angelo, E.; Costa, L.; Buglione, M.; Johnson, J.; Airoldi, M.; Mesia, R.; Resteghini, C.; Licitra, L.; Orlandi, E.; Martin, M.; Battaglia, P.; Turri-Zanoni, M.; Lionello, M.; Azzarello, G.; Boscolo, G.; Moro, C.; Maffioletti, L.; Iannacone, E.; Garassino, I.; Baatenburg de Jong, R. J.; Hardillo, J.; Mastromauro, C.; Menazza, S.; Secondino, S.; Montagnani, B. F.; Zustovich, F.; Da Corte, D.; De Renzi, F.; Aprile, G.; Pancheri, F.; Rossetto, C.; Ghiani, M.; Carta, P.; Dessi, A.; Cau, M. C.; Ramos, S.; Charoula, H.; Giannakopoulou, E.; Verstraete, H.; Nevens, D.; Velasco, M.; Bonfill, T.; Restoy, E. M.; Franzetti-Pellanda, A