RNA Editing for Muscular Dystrophy Therapy

Due to lack of effective therapies, muscular dystrophies became a focus for gene therapy. Multiple pre-clinical studies have shown successful restoration of dystrofin and dysferlin by RNA editing both in vivo and in vitro, but possibility of a clinical translation is still obscure. A number of new chemicals are being studied, and a search for new techniques is ongoing. This work is intended to give a brief overview of the current state of the RNA editing for treating muscular dystrophies

Pilot study of the safety and efficacy of angiogenic therapy in diabetic foot syndrome

BACKGROUND: The syndrome of diabetic foot remains the main cause of non-traumatic amputation of the lower extremity in the world. Even with the provision of comprehensive medical care in the conditions of a specialized center, 10-15% of patients do not succeed in healing the ulcerative defect due to the ischemic component. AIMS: The objective of this study is evaluation of safety and efficacy of pl-VEGF165 transfer in patients with neuroischemic type of diabetic foot syndrome. METHODS: The pilot study included 35 diabetic patients with neuroischemic foot ulcers (Wagner stage 1-2) who were not candidates for revascularization procedures (NCT02538705). The patients were closely monitored after repeated pl-VEGF165 intramuscular gene transfer (2,4 mg) at 1, 3, and 6 months after treatment. The primary efficacy endpoint was the surface area of the ulcers (sq.cm), the secondary endpoints were transcutaneous oxygen tension (Tcp02), ankle-brachial index (ABI), neuropathy disability score (NDS), neuropathy symptoms score (NSS), and Michigan neuropathy screening instrument (MNSI). Adverse events were monitored throughout the study. RESULTS: The use of pl-VEGF165 as part of complex treatment allowed to achieve wound healing in 65,7% of patients with chronic ulcerative defects, the safety of the target limb was 84%. Carrying out therapeutic angiogenesis as a part of the combined therapy ensured a reduction in the average area of the resistant to treatment defects from 3.6 [1.0; 7.05] cm2 to 0.0 [0.0;2.0] cm2 (p=0,001), which correlated with an increase in the TcPo2 index by 15% from 35 [29.5; 40.5] to 40.5 [36.0; 46.5] mm Hg (p= p=0,005) and in the ABI by 16% from 0.96 [0.82;1.08] to 1.11 [0.85; 1.24] (p=0,062). The decrease in the signs of diabetic neuropathy was determined - the scores of NSS scales and VAT decreased from 6,5 [5.75; 8.0) to 6.0 [5.25; 7.0] (p=0,004) and from 9.0 [8.0; 13.5] to 8.0 [7.0; 12.7] (p=0,001), respectively. No adverse effects associated with the use of pl-VEGF165 were recorded. CONCLUSIONS: Thus, preliminary results of the pilot study show that the use of pl-VEGF165 gene transfer in combination therapy allows for complete healing of neuroischemic diabetic foot ulcers in the majority of patients

Mecamylamine inhibits seizure-like activity in CA1-CA3 hippocampus through antagonism to nicotinic receptors.

Cholinergic modulation of hippocampal network function is implicated in multiple behavioral and cognitive states. Activation of nicotinic and muscarinic acetylcholine receptors affects neuronal excitability, synaptic transmission and rhythmic oscillations in the hippocampus. In this work, we studied the ability of the cholinergic system to sustain hippocampal epileptiform activity independently from glutamate and GABA transmission. Simultaneous CA3 and CA1 field potential recordings were obtained during the perfusion of hippocampal slices with the aCSF containing AMPA, NMDA and GABA receptor antagonists. Under these conditions, spontaneous epileptiform discharges synchronous between CA3 and CA1 were recorded. Epileptiform discharges were blocked by addition of the calcium-channel blocker Cd2+ and disappeared in CA1 after a surgical cut between CA3 and CA1. Cholinergic antagonist mecamylamine abolished CA3-CA1 synchronous epileptiform discharges, while antagonists of α7 and α4β2 nAChRs, MLA and DhβE, had no effect. Our results suggest that activation of nicotinic acetylcholine receptors can sustain CA3-CA1 synchronous epileptiform activity independently from AMPA, NMDA and GABA transmission. In addition, mecamylamine, but not α7 and α4β2 nAChRs antagonists, reduced bicuculline-induced seizure-like activity. The ability of mecamylamine to decrease hippocampal network synchronization might be associated with its therapeutic effects in a wide variety of CNS disorders including addiction, depression and anxiety

Seroprevalence of SARS-CoV-2 antibodies in Saint Petersburg, Russia : a population-based study

Properly conducted serological survey can help determine infection disease true spread. This study aims to estimate the seroprevalence of SARS-CoV-2 antibodies in Saint Petersburg, Russia accounting for non-response bias. A sample of adults was recruited with random digit dialling, interviewed and invited for anti-SARS-CoV-2 antibodies. The seroprevalence was corrected with the aid of the bivariate probit model that jointly estimated individual propensity to agree to participate in the survey and seropositivity. 66,250 individuals were contacted, 6,440 adults agreed to be interviewed and blood samples were obtained from 1,038 participants between May 27 and June 26, 2020. Naïve seroprevalence corrected for test characteristics was 9.0% (7.2–10.8) by CMIA and 10.5% (8.6–12.4) by ELISA. Correction for non-response decreased estimates to 7.4% (5.7–9.2) and 9.1% (7.2–10.9) for CMIA and ELISA, respectively. The most pronounced decrease in bias-corrected seroprevalence was attributed to the history of any illnesses in the past 3 months and COVID-19 testing. Seroconversion was negatively associated with smoking status, self-reported history of allergies and changes in hand-washing habits. These results suggest that even low estimates of seroprevalence can be an overestimation. Serosurvey design should attempt to identify characteristics that are associated both with participation and seropositivity.publishedVersionPeer reviewe

Design and Immunological Properties of the Novel Subunit Virus-like Vaccine against SARS-CoV-2

The COVID-19 pandemic is ongoing, and the need for safe and effective vaccines to prevent infection and to control spread of the virus remains urgent. Here, we report the development of a SARS-CoV-2 subunit vaccine candidate (Betuvax-CoV-2) based on RBD and SD1 domains of the spike (S) protein fused to a human IgG1 Fc fragment. The antigen is adsorbed on betulin adjuvant, forming spherical particles with a size of 100–180 nm, mimicking the size of viral particles. Here we confirm the potent immunostimulatory activity of betulin adjuvant, and demonstrate that two immunizations of mice with Betuvax-CoV-2 elicited high titers of RBD-specific antibodies. The candidate vaccine was also effective in stimulating a neutralizing antibody response and T cell immunity. The results indicate that Betuvax-CoV-2 has good potential for further development as an effective vaccine against SARS-CoV-2

Glu20Ter Variant in PLEC 1f Isoform Causes Limb-Girdle Muscle Dystrophy with Lung Injury

Plectinopathies are orphan diseases caused by PLEC gene mutations. PLEC is encoding the protein plectin, playing a role in linking cytoskeleton components in various tissues. In this study, we describe the clinical case of a 26-year-old patient with an early onset plectinopathy variant “limb-girdle muscle dystrophy type 2Q,” report histopathological and ultrastructural findings in m. vastus lateralis biopsy and a novel homozygous likely pathogenic variant (NM_201378.3:c.58G>T, NP_958780.1:p.Glu20Ter) in isoform 1f of the gene PLEC. The patient had an early childhood onset with retarded physical development, moderate weakness in pelvic girdle muscles, progressive weakening of limb-girdle muscles after the age of 21, pronounced atrophy of axial muscles, and hypertrophy of the gastrocnemius, deltoid, and triceps muscles, intermittent dyspnea, and no skin involvement. Findings included: non-infectious bronchiolitis and atelectasis signs, biopsy revealed myodystrophal pattern without macrophage infiltration, muscle fiber cytoskeleton disorganization resulted from the plectin loss, incomplete reparative rhabdomyogenesis, and moderate endomysial fibrosis. We have determined a novel likely pathogenic variant in PLEC 1f isoform that causes limb-girdle muscle dystrophy type 2Q and described the third case concerning an isolated myodystrophic phenotype of LGMD2Q with the likely pathogenic variant in PLEC 1f isoform. In addition, we have demonstrated the presence of severe lung injury in a patient and his siblings with the same myodystrophic phenotype and discussed the possible role of plectin deficiency in its pathogenesis

SARS-CoV-2 Subunit Virus-like Vaccine Demonstrates High Safety Profile and Protective Efficacy: Preclinical Study

Public health threat coming from a rapidly developing COVID-19 pandemic calls for developing safe and effective vaccines with innovative designs. This paper presents preclinical trial results of “Betuvax-CoV-2”, a vaccine developed as a subunit vaccine containing a recombinant RBD-Fc fusion protein and betulin-based spherical virus-like nanoparticles as an adjuvant (“Betuspheres”). The study aimed to demonstrate vaccine safety in mice, rats, and Chinchilla rabbits through acute, subchronic, and reproductive toxicity studies. Along with safety, the vaccine demonstrated protective efficacy through SARS-CoV-2-neutralizing antibody production in mice, rats, hamsters, rabbits, and primates (rhesus macaque), and lung damage and infection protection in hamsters and rhesus macaque model. Eventually, “Betuvax-CoV-2” was proved to confer superior efficacy and protection against the SARS-CoV-2 in preclinical studies. Based on the above results, the vaccine was enabled to enter clinical trials that are currently underway