The Genetic Markers of Knee Osteoarthritis in Women from Russia

Osteoarthritis is a chronic progressive joint disease that clinically debuts at the stage of pronounced morphologic changes, which makes treatment difficult. In this regard, an important task is the study of genetic markers of the disease, which have not been definitively established, due to the clinical and ethnic heterogeneity of the studied populations. To find the genetic markers for the development of knee osteoarthritis (OA) in women from the Volga-Ural region of Russia, we conducted research in two stages using different genotyping methods, such as the restriction fragment length polymorphism (RFLP) measurement, TaqMan technology and competitive allele-specific PCR-KASPTM. In the first stage, we studied polymorphic variants of candidate genes (ACAN, ADAMTS5, CHST11, SOX9, COL1A1) for OA development. The association of the *27 allele of the VNTR locus of the ACAN gene was identified (OR = 1.6). In the second stage, we replicated the GWAS results (ASTN2, ALDH1A2, DVWA, CHST11, GNL3, NCOA3, FILIP/SENP1, MCF2L, GLT8D, DOT1L) for knee OA studies. The association of the *T allele of the rs7639618 locus of the DVWA gene was detected (OR = 1.54). Thus, the VNTR locus of ACAN and the rs7639618 locus of DVWA are risk factors for knee OA in women from the Volga-Ural region of Russia.

Peak Bone Mass Formation: Modern View of the Problem

Peak bone mass is the amount of bone tissue that is formed when a stable skeletal state is achieved at a young age. To date, there are no established peak bone mass standards nor clear data on the age at which peak bone mass occurs. At the same time, the level of peak bone mass at a young age is an important predictor of the onset of primary osteoporosis. The purpose of this review is to analyze the results of studies of levels of peak bone mass in general, the age of its onset, as well as factors influencing its formation. Factors such as hormonal levels, body composition, physical activity, nutrition, heredity, smoking, lifestyle, prenatal predictors, intestinal microbiota, and vitamin and micronutrient status were considered, and a comprehensive scheme of the influence of these factors on the level of peak bone mass was created. Determining the standards and timing of the formation of peak bone mass, and the factors affecting it, will help in the development of measures to prevent its shortage and the consequent prevention of osteoporosis and concomitant diseases.

The Role of Hydrogen Sulfide in the Localization and Expression of p53 and Cell Death in the Nervous Tissue in Traumatic Brain Injury and Axotomy

Traumatic brain injury (TBI) is one of the leading causes of disability and death worldwide. It is characterized by various molecular-cellular events, with the main ones being apoptosis and damage to axons. To date, there are no clinically effective neuroprotective drugs. In this study, we examined the role of hydrogen sulfide (H2S) in the localization and expression of the key pro-apoptotic protein p53, as well as cell death in the nervous tissue in TBI and axotomy. We used a fast donor (sodium sulphide, Na2S) H2S and a classic inhibitor (aminooxyacetic acid, AOAA) of cystathionine β-synthase (CBS), which is a key enzyme in H2S synthesis. These studies were carried out on three models of neurotrauma in vertebrates and invertebrates. As a result, it was found that Na2S exhibits a pronounced neuroprotective effect that reduces the number of TUNEL-positive neurons and glial cells in TBI and apoptotic glia in axotomy. This effect could be realized through the Na2S-dependent decrease in the level of p53 in the cells of the nervous tissue of vertebrates and invertebrates, which we observed in our study. We also observed the opposite effect when using AOAA, which indicates the important role of CBS in the regulation of p53 expression and death of neurons and glial cells in TBI and axotomy.

Clinical and Genetic Characteristics of Calvarial Doughnut Lesions with Bone Fragility in Three Families with a Reccurent SGMS2 Gene Variant

Calvarial doughnut lesions (CDL) with bone fragility with or without spondylometaphyseal dysplasia (MIM: #126550) is a rare autosomal dominant skeletal disorder characterized by low bone mineral density, spinal and peripheral fractures, and specific sclerotic lesions of the cranial bones. In the current classification of skeletal disorders, the disease is included in the group of bone fragility disorders along with osteogenesis imperfecta. The disease is caused by pathogenic variants in the SGMS2 gene, the protein product of which is sphingomyelin synthase 2, which primarily contributes to sphingomyelin (SM) synthesis-the main lipid component of the plasma membrane essential for bone mineralization. To date, 15 patients from eight families with CDL with bone fragility have been described in the literature, and a recurrent variant c.148C>T (p.Arg50Ter) in the SGMS2 gene has been identified, which was found in patients from six families. We diagnosed the disease in 11 more patients from three unrelated families, caused by the same heterozygous nonsense variant c.148C>T (p.Arg50Ter) in the SGMS2 gene. Our results show wide interfamilial and intrafamilial phenotypic variability in patients with a detected recurrent variant in the SGMS2 gene, the presence of which must be taken into consideration in the diagnosis of the disease. The primary analysis of this variant will contribute to optimal molecular genetic diagnostics, which can reduce diagnostic costs and time.

The Role of Gasotransmitter-Dependent Signaling Mechanisms in Apoptotic Cell Death in Cardiovascular, Rheumatic, Kidney, and Neurodegenerative Diseases and Mental Disorders

Cardiovascular, rheumatic, kidney, and neurodegenerative diseases and mental disorders are a common cause of deterioration in the quality of life up to severe disability and death worldwide. Many pathological conditions, including this group of diseases, are based on increased cell death through apoptosis. It is known that this process is associated with signaling pathways controlled by a group of gaseous signaling molecules called gasotransmitters. They are unique messengers that can control the process of apoptosis at different stages of its implementation. However, their role in the regulation of apoptotic signaling in these pathological conditions is often controversial and not completely clear. This review analyzes the role of nitric oxide (NO), carbon monoxide (CO), hydrogen sulfide (H₂S), and sulfur dioxide (SO₂) in apoptotic cell death in cardiovascular, rheumatic, kidney, and neurodegenerative diseases. The signaling processes involved in apoptosis in schizophrenia, bipolar, depressive, and anxiety disorders are also considered. The role of gasotransmitters in apoptosis in these diseases is largely determined by cell specificity and concentration. NO has the greatest dualism; scales are more prone to apoptosis. At the same time, CO, H₂S, and SO₂ are more involved in cytoprotective processes.

AB0997 New epigenetic predictors of the various localizations osteoarthritis development

Background

Osteoarthritis (OA) is one of the most common joint diseases, often causing persistent pain and immobilization [1]. The genetic contribution to OA varies from 40% to 65%, depending on the presence of the pathology in the immediate family, the location of the affected joint, sex, and ethnicity of the patients [2]. The study of miRNA target sites is a new promising direction in molecular diagnostics [3].

Objectives

The aim of our work was to study the microRNA binding sites of COL1A1, COL11A1, ADAMTS5, MMP1, MMP13, SOX9, GDF5, FGF2, FGFR1, FGFRL1 genes in patients with OA of different localization.

Methods

A total of 417 women (mean age 51.67±11.5) from Ufa (Republic of Bashkortostan, Russia) participated in the study between January 2013 and August 2017. The patients were examined to diagnose for osteoarthritis according to the criteria of the American College of Rheumatologists (1995) with X-ray confirmation. Overall, 356 women with OA were recruited and divided into 3 groups as follows: subgroup 1 included 84 women affected by generalized OA, subgroup 2 included 197 women affected by knee OA, subgroup 3 included 75 women affected by hip OA.

For genotyping, RT-PCR analysis using KASP@ technology was used. Selection of the miRNA target loci was carried out using the database of the National Center for Biotechnological Information (https://www.ncbi.nlm.nih.gov), Ensemble Ge-nomeBrowser (www.ensembl.org), and the base of polymorphisms of microRNA target sites (http: // compbio. uthsc.edu/miRSNP). As a calculation tool, Statistica v.6.2 (StatSoft) software packages were used. Considering the type I error caused by multiple testing, p values were adjusted by calculating the FDR value using the Benjamini-Hochberg method (https://tools.carbocation.com/FDR).

Results

The T allele of the rs9659030 (COL11A1) was associated with the generalized OA (p = 0.019; OR = 2.0; 95% CI 1.11 to 3.62), the TT genotype was associated with total patients (p = 0.026; OR = 1.59; 95% CI 1.05 to 2.42), generalized OA (p = 0.003; OR = 2.75; 95% CI 1.39 to 5.46) and OA of the hip (p = 0.016; OR = 2.3; 95% CI 1.14 to 4.36). With respect to rs229069 (ADAMTS5), a significant association was found between the C allele and the incidence of total OA (p = 0.018; OR = 1.43; 95% CI 1.06 to 1.93), as well as with the knee OA (p = 0.042; OR = 1.43; 95% CI 1.01 to 2.03) and hip OA (p = 0.026; OR = 2.039; 95% CI 1.08 to 3.85). The CC genotype was also found to be associated with total OA (p = 0.037; OR = 1.53; 95% CI 1.02 to 2.28) and hip OA (p = 0.026; OR = 2.039; 95% CI 1.08 to 3.85). The T allele of rs13317 (FGFR1) was strongly associated with the total OA (p = 0.001; OR = 1.67; 95% CI 1.2 to 2.3), knee OA (p = 0.003; OR = 1.74; 95% CI 1.19 to 2.55) and generalized OA (p = 0.044; OR = 1.67; 95% CI 1.01 to 2.75)

After Benjamini-Hochberg correction, rs13317 remained statistically significant in the following groups: the T allele in control vs total patients (adjusted p*= 0.01) and in control vs OA of the knee (adjusted p* = 0.03). Neither the genotype nor the allele frequencies of rs1061347 (COL1A1), rs229077, rs9978597 (ADAMTS5), rs5854, rs470215 (MMP1), rs1042840 (MMP13), rs1042673 (SOX9), rs4647940 (FGFRL1) were significantly different between the affected individuals and normal controls.

Conclusion

The current study demonstrated an association between the T allele of rs13317 in FGFR1 and incidence of the total OA and knee OA in women from Volga-Ural region of Russia.

References

[1]Loeser, R., Goldring, S., Scanzello, C. and Goldring, M. (2012). Osteoarthritis: A disease of the joint as an organ. Arthritis & Rheumatism, 64(6), pp.1697-1707.

[2]Allen, K. (2010). Racial and ethnic disparities in osteoarthritis phenotypes. Current Opinion in Rheumatology, 22(5), pp.528-532.

[3]Zhang, X., Wang, C., Zhao, J., Xu, J., Geng, Y., Dai, L., Huang, Y., Fu, S., Dai, K. and Zhang, X. (2017). miR-146a facilitates osteoarthritis by regulating cartilage homeostasis via targeting Camk2d and Ppp3r2. Cell Death & Disease, 8(4), pp.e2734-e2734

Acknowledgements

The work was carried out within the framework of the program of activities of the world-class Eurasian Scientific and Educational Center at the expense of subsidies in the field of science from the budget of the Republic of Bashkortostan for state support of young scientists - postgrades and PhD (competition code - SEC-GMU-2021)

Disclosure of Interests

None declared

Osteogenesis Imperfecta: Search for Mutations in Patients from the Republic of Bashkortostan (Russia)

Osteogenesis imperfecta (OI) is an inherited disease of bone characterized by increased bone fragility. Here, we report the results of the molecular architecture of osteogenesis imperfecta research in patients from Bashkortostan Republic, Russia. In total, 16 mutations in COL1A1, 11 mutations in COL1A2, and 1 mutation in P3H1 and IFIMT5 genes were found in isolated states; 11 of them were not previously reported in literature. We found mutations in CLCN7, ALOX12B, PLEKHM1, ERCC4, ARSB, PTH1R, and TGFB1 that were not associated with OI pathogenesis in patients with increased bone fragility. Additionally, we found combined mutations (c.2869C>T, p. Gln957* in COL1A1 and c.1197+5G>A in COL1A2; c.579delT, p. Gly194fs in COL1A1 and c.1197+5G>A in COL1A2; c.2971G>C, p. Gly991Arg in COL1A2 and c.212G>C, p.Ser71Thr in FGF23; c.-14C>T in IFITM5 and c.1903C>T, p. Arg635* in LAMB3) in 4 patients with typical OI clinic phenotypes.