👤 A F Smirnov

Glucagon-like peptide-1 (GLP-1) is an incretin hormone secreted by intestinal endocrine L cells that activates the GLP-1 receptor (GLP-1R), leading to glucose-dependent insulin secretion and suppression of glucagon release. In recent years, GLP-1R agonists (GLP-1RAs) have become one of the leading therapeutic options for the treatment of type 2 diabetes mellitus; however, for a long time clinically approved GLP-1RAs were limited to peptide drugs unsuitable for oral administration. The discovery of the "first-in-class" small molecule agonist danuglipron in 2018 demonstrated the feasibility of orally available GLP-1RAs and stimulated the development of numerous danuglipron-like compounds, some of which showed increased efficacy over the prototype. In this study, we report the design and synthesis of novel GLP-1RAs based on a regioisomeric danuglipron scaffold, 1 Show less

Despite a proposed causal role for LDL-C (low-density lipoprotein cholesterol) in aortic stenosis (AS), randomized controlled trials of lipid-lowering therapy failed to prevent severe AS. We aimed to assess the impact on AS and peak velocity across the aortic valve conferred by lifelong alterations in LDL-C levels mediated by protein-disrupting variants in 3 clinically significant genes for LDL (low-density lipoprotein) metabolism ( We used sequencing data and electronic health records from UK Biobank (UKB) and All of Us and magnetic resonance imaging data from UKB. We identified predicted protein-disrupting variants with the Loss Of Function Transcript Effect Estimator (LOFTEE) and AlphaMissense algorithms and evaluated their associations with LDL-C and peak velocity across the aortic valve (UK Biobank), as well as diagnosed AS and aortic valve replacement (UK Biobank and All of Us). We included 421 049 unrelated participants (5621 with AS) in UKB and 195 519 unrelated participants (1087 with AS) in All of Us. Carriers of protein-disrupting variants in Rare genetic variants that confer lifelong higher or lower LDL-C levels are associated with substantially increased and decreased risk of AS, respectively. Early and sustained lipid-lowering therapy may slow or prevent AS development. Show less

Biallelic variants in CLN3 lead to a spectrum of diseases, ranging from severe neurodegeneration with retinal involvement (juvenile neuronal ceroid lipofuscinosis) to retina-restricted conditions. To provide a detailed description of the retinal phenotype of patients with isolated retinal degeneration harboring biallelic CLN3 pathogenic variants and to attempt a phenotype-genotype correlation associated with this gene defect. This retrospective cohort study included patients carrying biallelic CLN3 variants extracted from a cohort of patients with inherited retinal disorders (IRDs) investigated at the National Reference Center for Rare Ocular Diseases of the Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts from December 2007 to August 2020. Data were analyzed from October 2019 to August 2020. Functional (best-corrected visual acuity, visual field, color vision, and full-field electroretinogram), morphological (multimodal retinal imaging), and clinical data from patients were collected and analyzed. Gene defect was identified by either next-generation sequencing or whole-exome sequencing and confirmed by Sanger sequencing, quantitative polymerase chain reaction, and cosegregation analysis. Of 1533 included patients, 843 (55.0%) were women and 690 (45.0%) were men. A total of 15 cases from 11 unrelated families harboring biallelic CLN3 variants were identified. All patients presented with nonsyndromic IRD. Two distinct patterns of retinal disease could be identified: a mild rod-cone degeneration of middle-age onset (n = 6; legal blindness threshold reached by 70s) and a severe retinal degeneration with early macular atrophic changes (n = 9; legal blindness threshold reached by 40s). Eleven distinct pathogenic variants were detected, of which 4 were novel. All but 1, p.(Arg405Trp), CLN3 point variants and their genotypic associations were clearly distinct between juvenile neuronal ceroid lipofuscinosis and retina-restricted disease. Mild and severe forms of retina-restricted CLN3-linked IRDs also had different genetic background. These findings suggest CLN3 should be included in next-generation sequencing panels when investigating patients with nonsyndromic rod-cone dystrophy. These results document phenotype-genotype correlations associated with specific variants in CLN3. However, caution seems warranted regarding the potential neurological outcome if a pathogenic variant in CLN3 is detected in a case of presumed isolated IRD for the onset of neurological symptoms could be delayed. Show less

Transcription factors LXRs, PPARs, and SREBPs have been implicated in a multitude of physiological and pathological processes including atherogenesis. However, little is known about the regulation of these transcription factors at different stages of atherosclerosis progression. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to compare the contents of mRNAs in pairs intact-injured aorta fragments taken from the same donors. Only minor changes in LXRα, LXRβ, PPARα, PPARγ, SREBP1, and SREBP2 mRNA levels were found in initial lesions as compared with intact non-diseased tissue. The contents of all mRNAs but SREBP2 mRNA were found to be progressively up-regulated in fatty streaks and fibrous lipoid plaques. These changes were only partially reproduced in cultured macrophages upon lipid loading. Wave-shaped changes in abundance of correlations between given group of mRNAs and 28 atherosclerosis-related mRNA species in the course of atherogenesis were observed. The impact of specific mRNA correlations on the total correlations also significantly varied between different lesion types. The study suggests that the extent and forms of LXR/PPAR/SREBP participation in intima functions vary nonlinear in individual fashion in atherogenesis. We speculate that the observed changes in mRNAs expression and coupling reflect shifts in lipid ligands availability and cellular composition in the course of atherosclerosis progression. Show less

Double-color fluorescence in situ hybridization was performed on chicken chromosomes using seven unique clones from the human chromosome 3-specific NotI linking libraries. Six of them (NL1-097, NL2-092, NL2-230, NLM-007, NLM-118, and NLM-196) were located on the same chicken microchromosome and NL1-290 on another. Two chicken microchromosome GGA15-specific BAC clones, JE024F14 containing the IGVPS gene and JE020G17 containing the ALDH1A1 gene, were cytogenetically mapped to the same microchromosome that carried the six NotI linking clones, allowing identification of this chromosome as GGA15. Two GGA14-specific clones, JE027C23 and JE014E08 containing the HBA gene cluster, were co-localized on the same microchromosome as NL1-290, suggesting that this chromosome was GGA14. The results indicated that the human chromosomal region HSA3q13-->q23 is likely to be orthologous to GGA15 and GGA14. The breakpoint of evolutionary conservation of human and chicken chromosomes was detected on HSA3q13.3-->q23 between NL1-290, on the one hand, and six other NotI clones, on the other hand. Considering the available chicken-human comparative mapping data, another breakpoint appears to exist between the above NotI loci and four other genes, TFRC, EIF4A2, SKIL and DHX36 located on HSA3q24-->qter and GGA9. Based on human sequences within the NotI clones, localization of the six new chicken coding sequences orthologous to the human/rodent genes was suggested to be on GGA15 and one on GGA14. Microchromosomal location of seven NotI clones from the HSA3q21 T-band region can be considered as evidence in support of our hypothesis about the functional analogy of mammalian T-bands and avian microchromosomes. Show less

Mutations leading to decrease or absence of orthophosphate-repressible acid phosphatase activity have been studied. It is shown that these mutations can arise in three genes: acp1, acp2 and acp3, which are not linked. Genes acp1 and acp2 have been studied previously; the existence of the gene acp3 is demonstrated in this paper. It is established that all mutations in the acp3 gene are recessive, are leaky and epistatic to the constitutive mutations in all known regulatory genes for acid phosphatase II synthesis - acp4, acp80, acp81, acp82, acp83, and acp84. The gene acp3 is not linked with these regulatory genes, but it is closely linked with the structural gene for constitutive acid phosphatase - pho1 (D=0.33+/-0.20 cM). The pho1 gene has been recently located on the right arm of chromosome II on the left of the gene lys2. Mutations lacking activity of constitutive and repressible acid phosphatases simultaneously have been found. It is shown that these mutations are allelic to mutations in the gene acp3 and pho1 simultaneously. Two hypotheses are proposed about the role of the gene acp3: the gene controls the positive factor for the repressible acid phosphatase synthesis or the structure of the enzyme. Show less

Regulation of exocellular enzyme acid phosphatase 2 synthesis is studied. 21 mutants with consitutive synthesis of this enzyme are obtained by UV-irradiation. All mutants were recessive and were distributed among 3 complementation groups ACP80, ACP81, ACP82. Two groups, ACP80 and ACP81 corresponded to two different genes, which showed no linkage with ACP1, ACP2 and PHO1 genes. The type of synthesis of acid phosphatase 2 in strains acp1 acp80, acp1 acp81, acp2 acp80, acp2 acp81 is determined, and a conclusion is made about the participation of ACP2 gene in the regulation of acid phosphatase 2 synthesis. It is shown that some mutations in PHO1 gene, which block the activity of acid phosphatase 1, influence the activity and regulation of acid phosphatase 2. Show less