Significance of Mitochondrial Dysfunction in the Progression of Multiple Sclerosis.

The prevalence of multiple sclerosis and the complexity of its etiology and pathogenesis require further study of the factors underlying the progression of this disease. The prominent role of mitochondria in neurons makes this organelle a vulnerable target for CNS diseases. The purpose of this review is to consider the role of mitochondrial dysfunction in the pathogenesis of multiple sclerosis, as well as to propose new promising therapeutic strategies aimed at restoring mitochondrial function in multiple sclerosis.

Novel Models of Crohn's Disease Pathogenesis Associated with the Occurrence of Mitochondrial Dysfunction in Intestinal Cells.

Crohn's disease remains one of the challenging problems of modern medicine, and the development of new and effective and safer treatments against it is a dynamic field of research. To make such developments possible, it is important to understand the pathologic processes underlying the onset and progression of Crohn's disease at the molecular and cellular levels. During the recent years, the involvement of mitochondrial dysfunction and associated chronic inflammation in these processes became evident. In this review, we discuss the published works on pathogenetic models of Crohn's disease. These models make studying the role of mitochondrial dysfunction in the disease pathogenesis possible and advances the development of novel therapies.

Renin-Angiotensin System in Pathogenesis of Atherosclerosis and Treatment of CVD.

Atherosclerosis has complex pathogenesis, which involves at least three serious aspects: inflammation, lipid metabolism alterations, and endothelial injury. There are no effective treatment options, as well as preventive measures for atherosclerosis. However, this disease has various severe complications, the most severe of which is cardiovascular disease (CVD). It is important to note, that CVD is among the leading causes of death worldwide. The renin-angiotensin-aldosterone system (RAAS) is an important part of inflammatory response regulation. This system contributes to the recruitment of inflammatory cells to the injured site and stimulates the production of various cytokines, such as IL-6, TNF-a, and COX-2. There is also an association between RAAS and oxidative stress, which is also an important player in atherogenesis. Angiotensin-II induces plaque formation at early stages, and this is one of the most crucial impacts on atherogenesis from the RAAS. Importantly, while stimulating the production of ROS, Angiotensin-II at the same time decreases the generation of NO. The endothelium is known as a major contributor to vascular function. Oxidative stress is the main trigger of endothelial dysfunction, and, once again, links RAAS to the pathogenesis of atherosclerosis. All these implications of RAAS in atherogenesis lead to an explicable conclusion that elements of RAAS can be promising targets for atherosclerosis treatment. In this review, we also summarize the data on treatment approaches involving cytokine targeting in CVD, which can contribute to a better understanding of atherogenesis and even its prevention.

Anti-Inflammatory Therapy for Atherosclerosis: Focusing on Cytokines.

Atherosclerosis is a well-known global health problem. Despite the high prevalence of the disease, numerous aspects of pathogenesis remain unclear. Subsequently, there are still no cure or adequate preventive measures available. Atherogenesis is now considered a complex interplay between lipid metabolism alterations, oxidative stress, and inflammation. Inflammation in atherogenesis involves cellular elements of both innate (such as macrophages and monocytes) and adaptive immunity (such as B-cells and T-cells), as well as various cytokines cascades. Because inflammation is, in general, a well-investigated therapeutic target, and strategies for controlling inflammation have been successfully used to combat a number of other diseases, inflammation seems to be the preferred target for the treatment of atherosclerosis as well. In this review, we summarized data on targeting the most studied inflammatory molecular targets, CRP, IL-1ß, IL-6, IFN-γ, and TNF-α. Studies in animal models have shown the efficacy of anti-inflammatory therapy, while clinical studies revealed the incompetence of existing data, which blocks the development of an effective atheroprotective drug. However, all data on cytokine targeting give evidence that anti-inflammatory therapy can be a part of a complex treatment.

Some Molecular and Cellular Stress Mechanisms Associated with Neurodegenerative Diseases and Atherosclerosis.

Chronic stress is a combination of nonspecific adaptive reactions of the body to the influence of various adverse stress factors which disrupt its homeostasis, and it is also a corresponding state of the organism's nervous system (or the body in general). We hypothesized that chronic stress may be one of the causes occurence of several molecular and cellular types of stress. We analyzed literary sources and considered most of these types of stress in our review article. We examined genes and mutations of nuclear and mitochondrial genomes and also molecular variants which lead to various types of stress. The end result of chronic stress can be metabolic disturbance in humans and animals, leading to accumulation of reactive oxygen species (ROS), oxidative stress, energy deficiency in cells (due to a decrease in ATP synthesis) and mitochondrial dysfunction. These changes can last for the lifetime and lead to severe pathologies, including neurodegenerative diseases and atherosclerosis. The analysis of literature allowed us to conclude that under the influence of chronic stress, metabolism in the human body can be disrupted, mutations of the mitochondrial and nuclear genome and dysfunction of cells and their compartments can occur. As a result of these processes, oxidative, genotoxic, and cellular stress can occur. Therefore, chronic stress can be one of the causes forthe occurrence and development of neurodegenerative diseases and atherosclerosis. In particular, chronic stress can play a large role in the occurrence and development of oxidative, genotoxic, and cellular types of stress.

Analysis of mitochondrial DNA heteroplasmic mutations A1555G, C3256T, T3336C, С5178А, G12315A, G13513A, G14459A, G14846А and G15059A in CHD patients with the history of myocardial infarction.

The present study was undertaken in order to advance our earlier studies directed to define genetic risk of atherosclerotic vascular lesion development on a base on the analysis of sets of mutational load relevant to the mitochondrial genome mutations. A comparative evaluation of the two study participants' populations (that included coronary heart disease (CHD) patients who underwent myocardial infarction and apparently healthy donors with no clinical manifestations of coronary heart disease) on heteroplasmy levels of nine mutations of the mitochondrial genome (A1555G, C3256T, T3336C, С5178А, G12315A, G13513A, G14459A, G14846А and G15059A) that were shown previously to be associated with risk factors for atherosclerosis was performed. Close associations with the risk of cardiovascular disease were confirmed for mutation C3256T (gene MT-TL1), G12315A (gene MT-TL2), G13513A (gene MT-ND5) and G15059A (gene MT-CYB) by RT-PCR.

Study of the activated macrophage transcriptome.

Transcriptome analysis is a powerful modern tool to study possible alterations of gene expression associated with human diseases. It turns out to be especially promising for evaluation of gene expression changes in immunopathology, as immune cells have flexible gene expression patterns that can be switched in response to infection, inflammatory stimuli and exposure to various cytokines. In particular, macrophage polarization towards pro-inflammatory (M1) and anti-inflammatory (M2) phenotypes can be successfully studied using the modern transcriptome analysis approaches. The two mostly used techniques for transcriptome analysis are microarray and next generation sequencing. In this review we will provide an overview of known gene expression changes associated with immunopathology and discuss the advantage and limitations of different methods of transcriptome analysis.

Association of mutations in the mitochondrial genome with the subclinical carotid atherosclerosis in women.

The importance of the study of an association of mitochondrial DNA mutations with asymptomatic atherosclerosis in women is undeniable. In the present study, a series of PCR with primers for mutation region and further amplificate pyrosequencing were carried out to identify point substitutions or microdeletions of the mitochondrial genome. The results obtained were processed using the original method of estimating the level of heteroplasmy. Five mutations in the mitochondrial genome, namely C3256T, G14709A, G12315A, G13513A and G14846A, in which the heteroplasmy level was associated with the degree of preclinical atherosclerosis in women, were identified. The data obtained in the study showed that C3256T, G14709A and G12315A mutations have a positive correlation with atherosclerosis while G13513A and G14846A mutations have a negative correlation with atherosclerotic lesions. Total mutational load of the mitochondrial genome for C3256T, G14709A, G12315A, G13513A and G14846A mutations explains 68% of the variability of thickness of the carotid intima-medial layer, while the complex of traditional risk factors for cardiovascular diseases explains only 8% of the IMT variability. Data on the correlation between heteroplasmy levels of C3256T, G14709A, G12315A, G13513A and G14846A mutations prompt a suggestion that these mutations may be present on the same haplotypes of mitochondrial genome, associated with atherosclerosis.

Association of mitochondrial mutations with the age of patients having atherosclerotic lesions.

Mitochondrial genome mutations are associated with different pathologies. Earlier the authors of the study found an association of some mitochondrial genome mutations with atherosclerosis. In the present study, an attempt to analyze a connection of detected mutations with the age of patients with atherosclerosis was made. The investigated sample included 700 individuals, examined by ultrasonography in polyclinics of Moscow and the Moscow region. The sample was divided approximately into two equal parts. The first part included patients with carotid atherosclerosis. The second part included conventionally healthy study participants. In PCR-fragments of individuals' DNA the heteroplasmy level of investigated mutations was quantitatively measured by the method, developed by members of our laboratory on the basis of pyrosequencing technology. According to the obtained results mutations G12315A, G14459A and G15059A were significantly associated with the age of the study participants. The same time one nucleotide replacements A1555G and G14846A correlated negatively with the age at a high level of significance. Thus, in the present study an association of atherogenic mitochondrial genome mutations with age was found. Antiatherogenic mutations were correlated with the age negatively. This prompts a suggestion about common mechanisms of atherogenesis and aging.

Mitochondrial mutations are associated with atherosclerotic lesions in the human aorta.

Somatic mutations of the human mitochondrial genome can be a possible determinant of atherosclerosis. To test this possibility, forty mitochondrial mutations were analyzed in the present study in order to see which of these mutations might be associated with atherosclerosis. Ten mitochondrial mutations belonging to mitochondrial genes MT-RNR1 (rRNA 12S); MT-TL1 (tRNA-Leu, recognizes UUR); MT-TL2 (tRNA-Leu, recognizes CUN); MT-ND1, MT-ND2, MT-ND5, and MT-ND6 (subunits 1, 2, 5, and 6, respectively, of NADH dehydrogenase); and MT-CYB (cytochrome b) were potentially associated with atherosclerosis. From 29% (2 of 7 aortic samples) upto 86% (6 of 7 aortic samples) of aortic samples had a significant difference between atherosclerotic plaques and unaffected tissue, with the respect to the level of heteroplasmy for each mutation. Further, the homogenates of affected and normal intimae of 22 aortas were compared to reveal the average level of heteroplasmy for the above-mentioned 10 mutations. For five mutations, the mean level of heteroplasmy was significantly different in atherosclerotic intimal homogenates in comparison with the unaffected tissue. These mutations were A1555G, C3256T, T3336C, G13513A, and G15059A. Thus, it was demonstrated that at least five mitochondrial mutations occurring in MT-RNR1, MT-TL1, MT-ND2, MT-ND5, and MT-CYB genes are associated with atherosclerosis.

Mutations of mtDNA in some Vascular and Metabolic Diseases.

BACKGROUND: The present review article considers some chronic diseases of vascular and metabolic genesis, the causes of which may be mitochondrial dysfunction. Very often, in the long course of the disease, complications may occur, leading to myocardial infarction or ischemic stroke and, as a result, death. In particular, a large percentage of human deaths nowadays belongs to cardiovascular diseases, such as coronary heart disease (CHD), arterial hypertension, cardiomyopathies, and type 2 diabetes mellitus. OBJECTIVE: The aim of the present review was the analysis of literature sources, devoted to an investigation of a link of mitochondrial DNA mutations with chronic diseases of vascular and metabolic genesis. RESULTS: The analysis of literature indicates the association of the mitochondrial genome mutations with coronary heart disease, type 2 diabetes mellitus, hypertension, and various types of cardiomyopathies. CONCLUSION: The detected mutations can be used to analyze the predisposition to chronic diseases of vascular and metabolic genesis. They can also be used to create molecular-cell models necessary to evaluate the effectiveness of drugs developed for the treatment of these pathologies. MtDNA mutations associated with the absence of diseases of vascular and metabolic genesis could be potential candidates for gene therapy of the said diseases.

An original biomarker for the risk of developing cardiovascular diseases and their complications: Telomere length.

AIM: The aim of this work was to study the effect of telomere length in the chromosomes of nuclear blood cells in individuals with coronary heart disease (CHD) on the development of cardiovascular complications (CVC). MATERIALS AND METHODS: DNA was isolated from nuclear blood cells of 498 study participants. The telomere length was determined by real-time polymerase chain reaction. The investigation of each sample was repeated three times. Five years after the end of this study, a telephone survey of 119 patients with CHD was conducted in order to obtain data on the presence of CVC. RESULTS: According to the results obtained, a decrease in telomere length in patients with coronary heart disease increases the risk of subsequent development of cardiovascular complications. CONCLUSION: Patients with coronary heart disease with shorter telomeres compared with conventionally healthy study participants had an increased risk of cardiovascular complications within 5 years after telomere analysis.

Data on association of mitochondrial heteroplasmy with carotid intima-media thickness in subjects from Russian and Kazakh populations.

The search for variants of mitochondrial genome associated with atherosclerosis, in particular, with carotid intima-media thickness (cIMT), is necessary to understand the role of the damage of mitochondrial genome in the development of atherosclerosis. Such data can be useful to provide novel genetic markers of predisposition to atherosclerosis and molecular targets for further development of technologies aimed to prevent age-related degenerative pathologies. Data presented in this article demonstrate the association of several heteroplasmic variants of mitochondrial DNA (mtDNA) previously described as proatherogenic ones with cIMT in 251 participants (190 participants from Novosibirsk, Russia, and 61 participant from Almaty, Kazakhstan). It was shown that the occurrence of some variants of mitochondrial genome is different in samples derived from Russian and Kazakh populations; the level of mitochondrial heteroplasmy m.13513G > A correlates negatively with mean cIMT in both Russian and Kazakh participants.

Impact of Mitochondrial DNA Mutations on Carotid Intima-Media Thickness in the Novosibirsk Region.

The search for markers of predisposition to atherosclerosis development is very important for early identification of individuals with a high risk of cardiovascular disease. The aim of the present study was to investigate the association of mitochondrial DNA mutations with carotid intima-media thickness and to determine the impact of mitochondrial heteroplasmy measurements in the prognosis of atherosclerosis development. This cross-sectional, population-based study was conducted in 468 subjects from the Novosibirsk region. It was shown that the mean (carotid intima-media thickness) cIMT correlated with the following mtDNA mutations: m.15059G>A (r = 0.159, p = 0.001), m.12315G>A (r = 0.119; p = 0.011), m.5178C>A (r = 0.114, p = 0.014), and m.3256C>T (r = 0.130, p = 0.011); a negative correlation with mtDNA mutations m.14846G>A (r = -0.111, p = 0.042) and m.13513G>A (r = -0.133, p = 0.004) was observed. In the linear regression analysis, the addition of the set of mtDNA mutations to the conventional cardiovascular risk factors increased the ability to predict the cIMT variability from 17 to 27%. Multi-step linear regression analysis revealed the most important predictors of mean cIMT variability: age, systolic blood pressure, blood levels of total cholesterol, LDL and triglycerides, as well as the mtDNA mutations m.13513G>A, m.15059G>A, m.12315G>A, and m.3256C>T. Thus, a high predictive value of mtDNA mutations for cIMT variability was demonstrated. The association of mutation m.13513G>A and m.14846G>A with a low value of cIMT, demonstrated in several studies, represents a potential for the development of anti-atherosclerotic gene therapy.

Creation of Cybrid Cultures Containing mtDNA Mutations m.12315G>A and m.1555G>A, Associated with Atherosclerosis.

In the present work, a pilot creation of four cybrid cultures with high heteroplasmy level was performed using mitochondrial genome mutations m.12315G>A and m.1555G>A. According to data of our preliminary studies, the threshold heteroplasmy level of mutation m.12315G>A is associated with atherosclerosis. At the same time, for a mutation m.1555G>A, such a heteroplasmy level is associated with the absence of atherosclerosis. Cybrid cultures were created by fusion of rho0-cells and mitochondria from platelets with a high heteroplasmy level of the investigated mutations. To create rho0-cells, THP-1 culture of monocytic origin was taken. According to the results of the study, two cybrid cell lines containing mutation m.12315G>A with the heteroplasmy level above the threshold value (25% and 44%, respectively) were obtained. In addition, two cybrid cell lines containing mutation m.1555G>A with a high heteroplasmy level (24%) were obtained. Cybrid cultures with mtDNA mutation m.12315G>A can be used to model both the occurrence and development of atherosclerosis in cells and the titration of drug therapy for patients with atherosclerosis. With the help of cybrid cultures containing single nucleotide replacement of mitochondrial genome m.1555G>A, it is possible to develop approaches to the gene therapy of atherosclerosis.

Creation of Cultures Containing Mutations Linked with Cardiovascular Diseases using Transfection and Genome Editing.

OBJECTIVE: In this review article, we analyzed the literature on the creation of cultures containing mutations associated with cardiovascular diseases (CVD) using transfection, transduction and editing of the human genome. METHODS: We described different methods of transfection, transduction and editing of the human genome, used in the literature. RESULTS: We reviewed the researches in which the creation of сell cultures containing mutations was described. According to the literature, system CRISPR/Cas9 proved to be the most preferred method for editing the genome. We found rather promising and interesting a practically undeveloped direction of mitochondria transfection using a gene gun. Such a gun can direct a genetically-engineered construct containing human DNA mutations to the mitochondria using heavy metal particles. However, in human molecular genetics, the transfection method using a gene gun is unfairly forgotten and is almost never used. Ethical problems arising from editing the human genome were also discussed in our review. We came to a conclusion that it is impossible to stop scientific and technical progress. It is important that the editing of the genome takes place under the strict control of society and does not bear dangerous consequences for humanity. To achieve this, the constant interaction of science with society, culture and business is necessary. CONCLUSION: The most promising methods for the creation of cell cultures containing mutations linked with cardiovascular diseases, were system CRISPR/Cas9 and the gene gun.

Cybrid Models of Pathological Cell Processes in Different Diseases.

Modelling of pathological processes in cells is one of the most sought-after technologies of the 21st century. Using models of such processes may help to study the pathogenetic mechanisms of various diseases. The aim of the present study was to analyse the literature, dedicated to obtaining and investigating cybrid models. Besides, the possibility of modeling pathological processes in cells and treatment of different diseases using the models was evaluated. Methods of obtaining Rho0 cell cultures showed that, during their creation, mainly a standard technique, based on the use of mtDNA replication inhibitors (ethidium bromide), was applied. Cybrid lines were usually obtained by PEG fusion. Most frequently, platelets acted as donors of mitochondria. According to the analysis of the literature data, cybrid cell cultures can be modeled to study the dysfunction of the mitochondrial genome and molecular cellular pathological processes. Such models can be very promising for the development of therapeutic approaches to the treatment of various human diseases.

Mitochondrial diseases caused by mtDNA mutations: a mini-review.

There are several types of mitochondrial cytopathies, which cause a set of disorders, arise as a result of mitochondria's failure. Mitochondria's functional disruption leads to development of physical, growing and cognitive disabilities and includes multiple organ pathologies, essentially disturbing the nervous and muscular systems. The origins of mitochondrial cytopathies are mutations in genes of nuclear DNA encoding mitochondrial proteins or in mitochondrial DNA. Nowadays, numerous mtDNA mutations significant to the appearance and progress of pathologies in humans are detected. In this mini-review, we accent on the mitochondrial cytopathies related to mutations of mtDNA. As well known, there are definite set of symptoms of mitochondrial cytopathies distinguishing or similar for different syndromes. The present article contains data about mutations linked with cytopathies that facilitate diagnosis of different syndromes by using genetic analysis methods. In addition, for every individual, more effective therapeutic approach could be developed after wide-range mutant background analysis of mitochondrial genome.

Mitochondrial Genome Mutations Associated with Myocardial Infarction.

Myocardial infarction is one of the clinical manifestations of coronary heart disease. In some cases, the cause of myocardial infarction may be atherosclerotic plaques which occurred in the human aorta. The association of mtDNA mutations with atherosclerotic lesions in human arteries was previously detected by our research group. In this study, we used samples of white blood cells collected from 225 patients with myocardial infarction and 239 control persons with no health complaints. DNA was isolated from the blood leukocyte samples. Then, PCR fragments of DNA were obtained. They contained the investigated regions of 11 mitochondrial genome mutations (m.5178C>A, m.3336T>C, m.652delG, m.12315G>A, m.14459G>A, m.652insG, m.14846G>A, m.13513G>A, m.1555A>G, m.15059G>A, m.3256C>T). According to the obtained results, three mutations of the human mitochondrial genome correlated with myocardial infarction. A positive correlation was observed for mutation m.5178C>A. At the same time, a highly significant negative correlation with myocardial infarction was observed for mutation m.14846G>A. One single-nucleotide substitution of m.12315G>A had a trend towards negative correlation. These mutations can potentially be useful for creating molecular/cellular models for studying the mechanisms of myocardial infarction and designing novel therapies. Moreover, these mutations can possibly be used for diagnostic purposes.

Role of Mitochondrial Genome Mutations in Pathogenesis of Carotid Atherosclerosis.

Mutations of mtDNA, due to their higher frequency of occurrence compared to nuclear DNA mutations, are the most promising biomarkers for assessing predisposition of the occurrence and development of atherogenesis. The aim of the present article was an analysis of correlation of several mitochondrial genome mutations with carotid atherosclerosis. Leukocytes from blood of study participants from Moscow polyclinics were used as research material. The sample size was 700 people. The sample members were diagnosed with "atherosclerosis" on the basis of ultrasonographic examination and biochemical and molecular cell tests. DNA was isolated from blood leukocyte samples of the study participants. PCR fragments of DNA, containing the region of 11 investigated mutations, were pyrosequenced. The heteroplasmy level of these mutations was detected. Statistical analysis of the obtained results was performed using the software package SPSS 22.0. According to the obtained results, an association of mutations m.652delG, m.3336C>T, m.12315G>A, m.14459G>A m.15059G>A with carotid atherosclerosis was found. These mutations can be biomarkers for assessing predisposition to this disease. Additionally, two single nucleotide substitutions (m.13513G>A and m.14846G>A), negatively correlating with atherosclerotic lesions, were detected. These mutations may be potential candidates for gene therapy of atherosclerosis and its risk factors.