Iván Fernández-Frías, Sara Pérez-Luz, Javier Díaz-Nido, Molecular Therapy - Methods & Clinical Development, 2020, doi:10.1016/j.omtm.2020.03.005.
This work improved HSV-1 amplicons by genetic modification of the packaging cell line and optimization of the culture medium. A stably-transfected Vero 2-2 cell line overexpressing the anti-apoptotic Bcl-2 protein was generated, exhibiting an increased resistance to apoptosis, prolonged culture duration and a significant improvement in viral vector production. Additionally, supplementation of the growth medium with antioxidants, polyamines, amino acids and reduced glutathione further increased the yield of packaged amplicon vectors. With these modifications, HSV-1 amplicons could be isolated from culture supernatants instead of cell lysates, leading to vector preparations with higher titer and purity and paving the way for generation of stable cell lines that are capable of continuous herpesviral vector production.
Tuesday, March 17, 2020
Friday, March 13, 2020
Advances in drug therapy for mitochondrial diseases.
Lufei Zhang, Zhaoyong Zhang, Aisha Khan, Hui Zheng, Chao Yuan, Haishan Jiang; Annals of Translational Medicine, 01 Jan 2020, 8(1):17
DOI: 10.21037/atm.2019.10.113
Mitochondrial diseases are a group of clinically and genetically heterogeneous disorders driven by oxidative phosphorylation dysfunction of the mitochondrial respiratory chain which due to pathogenic mutations of mitochondrial DNA (mtDNA) or nuclear DNA (nDNA). Recent progress in molecular genetics and biochemical methodologies has provided a better understanding of the etiology and pathogenesis of mitochondrial diseases, and this has expanded the clinical spectrum of this conditions. But the treatment of mitochondrial diseases is largely symptomatic and thus does not significantly change the course of the disease. Few clinical trials have led to the design of drugs aiming at enhancing mitochondrial function or reversing the consequences of mitochondrial dysfunction which are now used in the clinical treatment of mitochondrial diseases. Several other drugs are currently being evaluated for clinical management of patients with mitochondrial diseases. In this review, the current status of treatments for mitochondrial diseases is described systematically, and newer potential treatment strategies for mitochondrial diseases are also discussed.
DOI: 10.21037/atm.2019.10.113
Mitochondrial diseases are a group of clinically and genetically heterogeneous disorders driven by oxidative phosphorylation dysfunction of the mitochondrial respiratory chain which due to pathogenic mutations of mitochondrial DNA (mtDNA) or nuclear DNA (nDNA). Recent progress in molecular genetics and biochemical methodologies has provided a better understanding of the etiology and pathogenesis of mitochondrial diseases, and this has expanded the clinical spectrum of this conditions. But the treatment of mitochondrial diseases is largely symptomatic and thus does not significantly change the course of the disease. Few clinical trials have led to the design of drugs aiming at enhancing mitochondrial function or reversing the consequences of mitochondrial dysfunction which are now used in the clinical treatment of mitochondrial diseases. Several other drugs are currently being evaluated for clinical management of patients with mitochondrial diseases. In this review, the current status of treatments for mitochondrial diseases is described systematically, and newer potential treatment strategies for mitochondrial diseases are also discussed.
Tuesday, March 10, 2020
Outlining the Complex Pathway of Mammalian Fe-S Cluster Biogenesis
Nunziata Maio, Tracey A. Rouault; Trends in Biochemical Sciences, 2020, doi:10.1016/j.tibs.2020.02.001.
Structural determinations of the architecture of the initial ISC biogenesis complex, comprising NFS1, ISD11, ACP, ISCU, and FXN, have shed light on the interactions that govern de novo ISC assembly.
Structural determinations of the architecture of the initial ISC biogenesis complex, comprising NFS1, ISD11, ACP, ISCU, and FXN, have shed light on the interactions that govern de novo ISC assembly.
Sunday, March 8, 2020
The Assessment of Upper Limb Functionality in Friedreich Ataxia via Self-Feeding Activity
K. D. Nguyen, L. A. Corben, P. N. Pathirana, M. K. Horne, M. B. Delatycki and D. J. Szmulewicz, IEEE Transactions on Neural Systems and Rehabilitation Engineering. DOI: 10.1109/TNSRE.2020.2977354
The objective assessment of motor impairment resulting from neurological disorders forms the basis for effective rehabilitation and therapeutic programs. Such assessments conducted through the engagement of suitable daily activities can serve as an effective surrogate measure for the assessment of independent living. This study considers an instrumented spoon in the assessment of upper-limb functionality through the self-feeding activity of a group of individuals clinically diagnosed with the debilitating condition, Friedreich ataxia (FRDA). Thirty-five subjects with FRDA (34±14 years old) and 14 age-matched healthy subjects performed three cycles of self-feeding consisting of grasping, scooping, transferring food to mouth and returning the spoon. Parameters relating to the feeding rate, trajectory of the rotation, range of motion and movement variability with specific attention to each segment were considered for the capture of ataxia pertaining to the disability. Movement variability measured by Dynamic Time Warping (DTW) resulted in an average accuracy of 96% in the diagnosis of ataxia (separation of the two cohorts). The severity of ataxia estimated using a combination of features from Random Forest (RF) increased the correlation with the clinical estimates of ataxia by 13% and achieved higher coefficient (0.72 in patient scale) than the currently used tests (Box & Block, Pegboard). While the overall results provided an objective, daily activity based means of capturing intrinsic abnormalities, the different segments of the task demonstrated the presence of ataxia in a spatial context concurring with relevant clinical observations.
The objective assessment of motor impairment resulting from neurological disorders forms the basis for effective rehabilitation and therapeutic programs. Such assessments conducted through the engagement of suitable daily activities can serve as an effective surrogate measure for the assessment of independent living. This study considers an instrumented spoon in the assessment of upper-limb functionality through the self-feeding activity of a group of individuals clinically diagnosed with the debilitating condition, Friedreich ataxia (FRDA). Thirty-five subjects with FRDA (34±14 years old) and 14 age-matched healthy subjects performed three cycles of self-feeding consisting of grasping, scooping, transferring food to mouth and returning the spoon. Parameters relating to the feeding rate, trajectory of the rotation, range of motion and movement variability with specific attention to each segment were considered for the capture of ataxia pertaining to the disability. Movement variability measured by Dynamic Time Warping (DTW) resulted in an average accuracy of 96% in the diagnosis of ataxia (separation of the two cohorts). The severity of ataxia estimated using a combination of features from Random Forest (RF) increased the correlation with the clinical estimates of ataxia by 13% and achieved higher coefficient (0.72 in patient scale) than the currently used tests (Box & Block, Pegboard). While the overall results provided an objective, daily activity based means of capturing intrinsic abnormalities, the different segments of the task demonstrated the presence of ataxia in a spatial context concurring with relevant clinical observations.
Thursday, March 5, 2020
Polyunsaturated Fatty Acid Deuteration against Neurodegeneration
Mikhail S. Shchepinov, Trends in Pharmacological Sciences, 2020, doi:10.1016/j.tips.2020.01.010.
Regioselective deuteration that reinforces oxidation-prone, bis-allylic sites of PUFAs is a novel, nonantioxidant treatment modality that dramatically reduces LPO, potentially mitigating numerous diseases through preservation of membrane properties and amelioration of oxidative stress. Animal disease models and several ongoing human clinical trials highlight the potential of the deuterated-PUFA (D-PUFA) drug candidates currently in development.
Regioselective deuteration that reinforces oxidation-prone, bis-allylic sites of PUFAs is a novel, nonantioxidant treatment modality that dramatically reduces LPO, potentially mitigating numerous diseases through preservation of membrane properties and amelioration of oxidative stress. Animal disease models and several ongoing human clinical trials highlight the potential of the deuterated-PUFA (D-PUFA) drug candidates currently in development.
Wednesday, March 4, 2020
Identification of Frataxin as a regulator of ferroptosis
Jing Du, Yi Zhou, Yanchun Li, Jun Xia, Yongjian Chen, Sufeng Chen, Xin Wang, Weidong Sun, Tongtong Wang, Xueying Ren, Xu Wang, Yihan An, Kang Lu, Wanye Hu, Siyuan Huang, Jianghui Li, Xiangmin Tong, Ying Wang; Redox Biology, 2020, 101483, doi:10.1016/j.redox.2020.101483.
This paper suggests that FXN is a novel ferroptosis modulator, as well as a potential provided target to improve the antitumor activity based on ferroptosis.
This paper suggests that FXN is a novel ferroptosis modulator, as well as a potential provided target to improve the antitumor activity based on ferroptosis.
Tuesday, March 3, 2020
An Overview of the Current State and the Future of Ataxia Treatments
Kimberly Tsu Kwei, Sheng-Han Kuo; Neurologic Clinics, 2020, doi:10.1016/j.ncl.2020.01.008.
Keywords: Cerebellum; Ataxia; Multiple system atrophy; Spinocerebellar ataxia; Friedreich ataxia; Ataxia treatment
Keywords: Cerebellum; Ataxia; Multiple system atrophy; Spinocerebellar ataxia; Friedreich ataxia; Ataxia treatment
Sunday, March 1, 2020
Epigenetic regulation of clinical manifestations of Friedreich's disease
Nuzhny EP, Abramycheva NY, Nikolaeva NS, Ershova MV, Klyushnikov SA, Illarioshkin SN, Fedotova EY.; Zh Nevrol Psikhiatr Im S S Korsakova. 2020;120(1):20-26. doi: 10.17116/jnevro202012001120. [Article in Russian; Abstract available in Russian from the publisher]
Correlations between the methylation level of CpG-sites in UP-GAA and DOWN-GAA and the number of GAA repeats in both expanded FXN alleles in patients with FD were found. An analysis revealed an earlier onset and a more severe course of FD in cases with hypermethylation of several CpG-sites in the UP-GAA region. The correlation between the methylation pattern and the presence of extraneural manifestations of FD was also revealed. In FD patients with cardiomyopathy, a hypomethylated CpG-site in the promoter region was found. In FD patients with carbohydrate metabolism disorders, two hypomethylated CpG-sites in the DOWN-GAA region were observed.
Correlations between the methylation level of CpG-sites in UP-GAA and DOWN-GAA and the number of GAA repeats in both expanded FXN alleles in patients with FD were found. An analysis revealed an earlier onset and a more severe course of FD in cases with hypermethylation of several CpG-sites in the UP-GAA region. The correlation between the methylation pattern and the presence of extraneural manifestations of FD was also revealed. In FD patients with cardiomyopathy, a hypomethylated CpG-site in the promoter region was found. In FD patients with carbohydrate metabolism disorders, two hypomethylated CpG-sites in the DOWN-GAA region were observed.
Sunday, February 23, 2020
Management of Neuroinflammatory Responses to AAV-Mediated Gene Therapies for Neurodegenerative Diseases
Perez, B.A.; Shutterly, A.; Chan, Y.K.; Byrne, B.J.; Corti, M.; Brain Sci. 2020, 10, 119; doi:10.3390/brainsci10020119 (registering DOI)
Recently, adeno-associated virus (AAV)-mediated gene therapies have attracted clinical interest for treating neurodegenerative diseases including spinal muscular atrophy (SMA), Canavan disease (CD), Parkinson’s disease (PD), and Friedreich’s ataxia (FA). The influx of clinical findings led to the first approved gene therapy for neurodegenerative disorders in 2019 and highlighted new safety concerns for patients. Large doses of systemically administered AAV stimulate host immune responses, resulting in anti-capsid and anti-transgene immunity with implications for transgene expression, treatment longevity, and patient safety. Delivering lower doses directly to the central nervous system (CNS) is a promising alternative, resulting in higher transgene expression with decreased immune responses. However, neuroinflammatory responses after CNS-targeted delivery of AAV are a critical concern. Reported signs of AAV-associated neuroinflammation in preclinical studies include dorsal root ganglion (DRG) and spinal cord pathology with mononuclear cell infiltration. In this review, we discuss ways to manage neuroinflammation, including choice of AAV capsid serotypes, CNS-targeting routes of delivery, genetic modifications to the vector and/or transgene, and adding immunosuppressive strategies to clinical protocols. As additional gene therapies for neurodegenerative diseases enter clinics, tracking biomarkers of neuroinflammation will be important for understanding the impact immune reactions can have on treatment safety and efficacy.
Recently, adeno-associated virus (AAV)-mediated gene therapies have attracted clinical interest for treating neurodegenerative diseases including spinal muscular atrophy (SMA), Canavan disease (CD), Parkinson’s disease (PD), and Friedreich’s ataxia (FA). The influx of clinical findings led to the first approved gene therapy for neurodegenerative disorders in 2019 and highlighted new safety concerns for patients. Large doses of systemically administered AAV stimulate host immune responses, resulting in anti-capsid and anti-transgene immunity with implications for transgene expression, treatment longevity, and patient safety. Delivering lower doses directly to the central nervous system (CNS) is a promising alternative, resulting in higher transgene expression with decreased immune responses. However, neuroinflammatory responses after CNS-targeted delivery of AAV are a critical concern. Reported signs of AAV-associated neuroinflammation in preclinical studies include dorsal root ganglion (DRG) and spinal cord pathology with mononuclear cell infiltration. In this review, we discuss ways to manage neuroinflammation, including choice of AAV capsid serotypes, CNS-targeting routes of delivery, genetic modifications to the vector and/or transgene, and adding immunosuppressive strategies to clinical protocols. As additional gene therapies for neurodegenerative diseases enter clinics, tracking biomarkers of neuroinflammation will be important for understanding the impact immune reactions can have on treatment safety and efficacy.
Monday, February 17, 2020
A Phase 2 Clinical Trial to Test the Safety and Efficacy of Etravirine in Friedreich Ataxia Patients (FAEST1)
ClinicalTrials.gov Identifier: NCT04273165. February 17, 2020, Sponsor: IRCCS Eugenio Medea, Collaborator: University of Rome Tor Vergata.
A drug repositioning effort provided evidence supporting the possible use of Etravirine, a drug approved for the treatment of HIV infections in patients starting from 2 years of age, as a treatment for FA. We found that Etravirine is able to increase Frataxin protein both in vitro - in cells derived from FA patients - and in vivo - in the heart and skeletal muscle of Frataxin-deficient YG8 mice. Because of these findings, and since Etravirine displays a generally favorable safety profile, we plan to launch an open-label, phase 2 clinical trial aimed at assessing the safety and efficacy of Etravirine in FA patients. We aim at recruiting 30 FA patients. 15 will be treated with Etravirine for 4 months at 200 mcg/day and 15 will be treated with Etravirine for 4 months at 400 mg/day. Efficacy primary endpoint will be represented changes in peak VO2 as measured by incremental cycle ergometer exercise test. Secondary endpoints will include maximal workload, SARA score, cardiac measures, Frataxin protein levels in peripheral blood mononuclear cells and molecular analysis of Frataxin mRNA translation efficiency. Complete sets of data will be collected 4 months before the start of the treatment (T -4), at the start (T0), after 2 months (T2), at the end of the treatment (T4) and 4 months after the termination of the treatment (T8).
A drug repositioning effort provided evidence supporting the possible use of Etravirine, a drug approved for the treatment of HIV infections in patients starting from 2 years of age, as a treatment for FA. We found that Etravirine is able to increase Frataxin protein both in vitro - in cells derived from FA patients - and in vivo - in the heart and skeletal muscle of Frataxin-deficient YG8 mice. Because of these findings, and since Etravirine displays a generally favorable safety profile, we plan to launch an open-label, phase 2 clinical trial aimed at assessing the safety and efficacy of Etravirine in FA patients. We aim at recruiting 30 FA patients. 15 will be treated with Etravirine for 4 months at 200 mcg/day and 15 will be treated with Etravirine for 4 months at 400 mg/day. Efficacy primary endpoint will be represented changes in peak VO2 as measured by incremental cycle ergometer exercise test. Secondary endpoints will include maximal workload, SARA score, cardiac measures, Frataxin protein levels in peripheral blood mononuclear cells and molecular analysis of Frataxin mRNA translation efficiency. Complete sets of data will be collected 4 months before the start of the treatment (T -4), at the start (T0), after 2 months (T2), at the end of the treatment (T4) and 4 months after the termination of the treatment (T8).
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