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Mitochondrial fusion is essential to mitochondrial fitness and cellular health. Neurons of patients with genetic neurodegenerative diseases often exhibit mitochondrial fragmentation, reflecting an imbalance in mitochondrial fusion and fission (mitochondrial dysdynamism). Charcot–Marie–Tooth (CMT) disease type 2A is the prototypical disorder of impaired mitochondrial fusion caused by mutations in the fusion protein mitofusin (MFN)2. Yet, cultured CMT2A patient fibroblast mitochondria are often reported as morphologically normal. Metabolic stress might evoke pathological mitochondrial phenotypes in cultured patient fibroblasts, providing a platform for the pre-clinical individualized evaluation of investigational therapeutics. Here, substitution of galactose for glucose in culture media was used to redirect CMT2A patient fibroblasts (MFN2 T105M, R274W, H361Y, R364W) from glycolytic metabolism to mitochondrial oxidative phosphorylation, which provoked characteristic mitochondrial fragmentation and depolarization and induced a distinct transcriptional signature. Pharmacological MFN activation of metabolically reprogrammed fibroblasts partially reversed the mitochondrial abnormalities in CMT2A and CMT1 and a subset of Parkinson's and Alzheimer's disease patients, implicating addressable mitochondrial dysdynamism in these illnesses. [ABSTRACT FROM AUTHOR]

Charcot-Marie-Tooth disease type 2A (CMT2A) is an untreatable childhood peripheral neuropathy caused by mutations of the mitochondrial fusion protein, mitofusin (MFN) 2. Here, pharmacological activation of endogenous normal mitofusins overcame dominant inhibitory effects of CMT2A mutants in reprogrammed human patient motor neurons, reversing hallmark mitochondrial stasis and fragmentation independent of causal MFN2 mutation. In mice expressing human MFN2 T105M, intermittent mitofusin activation with a small molecule, MiM111, normalized CMT2A neuromuscular dysfunction, reversed pre-treatment axon and skeletal myocyte atrophy, and enhanced axon regrowth by increasing mitochondrial transport within peripheral axons and promoting in vivo mitochondrial localization to neuromuscular junctional synapses. MiM111-treated MFN2 T105M mouse neurons exhibited accelerated primary outgrowth and greater post-axotomy regrowth, linked to enhanced mitochondrial motility. MiM111 is the first pre-clinical candidate for CMT2A. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To determine whether use of uterine balloon tamponade (UBT) for management of uncontrolled postpartum hemorrhage (PPH) by community-based providers in a resource-limited setting could be feasible, effective, and safe. Methods: In rural South Sudan, community providers were trained and equipped with a simple UBT device consisting of a catheter, condom, and syringe. Snowball sampling identified cases of UBT use since training. Semi-structured interviews were conducted among community providers, referral facility providers, patients, and patient family members. Interview transcripts were analyzed using qualitative methods. Results: Thirteen cases were identified and 24 interviews related to community-based UBT use were conducted. Qualitative analysis revealed several major themes. Community providers applied UBT in appropriate clinical situations. UBT was effective for controlling PPH, even among severely ill patients. Referral was difficult and lengthy owing to the austere setting, but simple UBT appeared to mitigate these challenges. Communities had some initial fears, yet ultimately embraced UBT. Equipment and supplies were largely maintained. There was universal satisfaction with UBT among patients, family members, and providers. One death occurred among the 13 cases, although it was probably not attributable to PPH. Conclusion: Training and UBT device provision are simple, affordable, and effective for managing uncontrolled PPH in a resource-limited setting. [Copyright &y& Elsevier]