bims-curels Biomed News
on Leigh syndrome
Issue of 2023‒01‒22
four papers selected by
Cure Mito Foundation

  1. Stem Cell Res. 2023 Jan 17. pii: S1873-5061(23)00016-8. [Epub ahead of print]67 103030
      We generated two pairs of mother-child iPSCs lines for Maternally Inherited Leigh Syndrome (MILS) carrying the m.8993 T > G and m.9176 T > G mutations in the MT-ATP6 gene. We delivered reprogramming factors OCT4, SOX2, KLF4, and c-MYC via Sendai virus. All iPSCs lines had a normal karyotype, expressed pluripotency markers, and differentiated into the three germ layers. Both patient-iPSCs retained the same degrees of heteroplasmy as their source fibroblasts (>97.0 %). In maternal iPSCs, the heteroplasmy remained 0.0 % in the case of the m.8993 T > G mutation and dropped from 55.0 % to 1.0 % in the case of m.9176 T > G mutation.
  2. Pharmaceut Med. 2023 Jan 18.
      The approach to patient engagement (PE) in drug development has changed rapidly due to many factors, including the complexity of innovative drugs and the need to demonstrate outcomes of relevance to patients, the desire to show 'value add' of PE, and the pandemic-related changes to how clinical trials are run, e.g., decentralised studies. In parallel, there have been changes in technology-assisted ways of running clinical trials, capturing patient health outcomes and preferences, an increasing societal demand for diversity and inclusion, and efforts to improve clinical trial efficiency, transparency, and accountability. Organisations are beginning to monitor PE activities and outcomes more effectively to learn and inform future PE strategies. As a result, these factors are facilitating the incorporation of patients' lived experience, preferences and needs into the design and running of clinical trials more than ever before. In this paper, the authors reflect upon these last few years, the emerging trends and their drivers, and where we may expect PE in clinical research to progress in the near future.
  3. Orphanet J Rare Dis. 2023 Jan 19. 18(1): 14
      300 million people live with at least one of 6,000 rare diseases worldwide. However, rare disease research is not always reviewed with scrutiny, making it susceptible to what the author refers to as nontransparent science. Nontransparent science can obscure animal model flaws, misguide medicine regulators and drug developers, delay or frustrate orphan drug development, or waste limited resources for rare disease research. Flawed animal models not only lack pharmacologic relevance, but also give rise to issue of clinical translatability. Sadly, these consequences and risks are grossly overlooked. Nontransparency in science can take many forms, such as premature publication of animal models without clinically significant data, not providing corrections when flaws to the model are discovered, lack of warning of critical study limitations, missing critical control data, questionable data quality, surprising results without a sound explanation, failure to rule out potential factors which may affect study conclusions, lack of sufficient detail for others to replicate the study, dubious authorship and study accountability. Science has no boarders, neither does nontransparent science. Nontransparent science can happen irrespective of the researcher's senority, institutional affiliation or country. As a patient-turned researcher suffering from Bietti crystalline dystrophy (BCD), I use BCD as an example to analyze various forms of nontransparent science in rare disease research. This article analyzes three papers published by different research groups on Cyp4v3-/-, high-fat diet (HFD)-Cyp4v3-/-, and Exon1-Cyp4v3-/- mouse models of BCD. As the discussion probes various forms of nontransparent science, the flaws of these knockout mouse models are uncovered. These mouse models do not mimic BCD in humans nor do they address the lack of Cyp4v3 (murine ortholog of human CYP4V2) expression in wild type (WT) mouse retina which is markedly different from CYP4V2 expression in human retina. Further, this article discusses the impact of nontransparent science on drug development which can lead to significant delays ultimately affecting the patients. Lessons from BCD research can be helpful to all those suffering from rare diseases. As a patient, I call for transparent science in rare disease research.
    Keywords:  Animal model flaws; Bietti Crystalline Dystrophy; Cyp4v3 knockout mouse; Genetic background; Interspecies differences; Orphan Drug Development; Patient perspective; Rare Disease Research; Transparent science
  4. Biomolecules. 2023 Jan 07. pii: 126. [Epub ahead of print]13(1):
      Mitochondrial diabetes (MD) is generally classified as a genetic defect of β-cells. The main pathophysiology is insulin secretion failure in pancreatic β-cells due to impaired mitochondrial ATP production. However, several reports have mentioned the presence of insulin resistance (IR) as a clinical feature of MD. As mitochondrial dysfunction is one of the important factors causing IR, we need to focus on IR as another pathophysiology of MD. In this special issue, we first briefly summarized the insulin signaling and molecular mechanisms of IR. Second, we overviewed currently confirmed pathogenic mitochondrial DNA (mtDNA) mutations from the MITOMAP database. The variants causing diabetes were mostly point mutations in the transfer RNA (tRNA) of the mitochondrial genome. Third, we focused on these variants leading to the recently described "tRNA modopathies" and reviewed the clinical features of patients with diabetes. Finally, we discussed the pathophysiology of MD caused by mtDNA mutations and explored the possible mechanism underlying the development of IR. This review should be beneficial to all clinicians involved in diagnostics and therapeutics related to diabetes and mitochondrial diseases.
    Keywords:  insulin resistance; mitochondrial DNA mutation; mitochondrial diabetes; transfer RNA modopathy