|
|
The effect of individual components of bee venom on the human body
Spurný, Jakub ; Horníková, Daniela (advisor) ; Čapková Frydrychová, Radmila (referee)
The honeybee (Apis mellifera) uses the sting apparatus to defend itself. It consists of a sting's part and a part related to the production of poison. Bee venom is secreted by special venom glands of bees. The chemical composition of the poison is a mixture of amino acides, peptides and enzymes with the various (patho)physiological effects. Some components of bee venom, for example, cause the breakdown of red blood cells, inhibit tissue excitement, increase heart rate and mean arterial pressure or cause an allergic reaction. On the other hand, the same components of bee venom also show significant positive effects on the human body. These effects have been reported in some diseases of the nervous system (Parkinson's and Alzheimer's disease), the cardiovascular system (atherosclerosis), integument (Acne vulgaris) and in the treatment of oncological diseases. For this reason, the study of bee venom components and their potential use in the therapy of various pathological conditions and diseases is important. Key words: sting apparatus; bee venom; organ system; therapy
|
|
|
Control of creatine kinase activity due to structural changes of the enzyme molecule
Horníková, Daniela
Myofibrillar creatine kinase (CK) has been studied for activity control due to structural changes of its molecule. Data indicating three CK conformations for three substrate ligation states were collected, using fluorescence and absorption spectroscopy. As the radius of CK molecule under ligation states: CK free, CK-ATP+creatine and CK-ATP complexes decreases, in the same block sequence decrease: fluorescence lifetimes 2.72, 2.42, 2.38 ns of intrinsic tryptophans emission, anisotropy decays, rotation correlation times 35, 29, 27 ns and acrylamide quenching. Data were confirmed by anisotropy experiments with CK-(FITC labelled), providing the correlation times 34, 30, 27 ns. Results indicate that besides the "energy minimizing" conformational effects of substrates, other essential components of physiological control at the subcellular level should be involved in the transition of the CK- ATP+creatine complex from the intermediary (nonreactive) to the closed (reactive) conformation of the molecule. Keywords: creatine kinase, conformational effect of substrates, enzyme activity control.
|
|
|
The effect of chronic cold on Ca2+-ATPase (SERCA2) in rat heart
Šeovićová, Maja ; Horníková, Daniela (advisor) ; Nováková, Olga (referee)
Acute cold exposure is a significant stressor activating heat production by shivering after the prolonged exposure cellular oxidative stress increases. Chronic exposure to cold lasting at least 2 weeks leads to the development of cold acclimatization. The main thermogenic role is taken over by non-shivering thermogenesis taking place in brown adipose tissue, which significantly increases its weight due to cold. Cardiac hypertrophy, hypertension and impaired renal function are frequently observed pathologies of acclimatization at 4-5 řC. Our laboratory recently introduced a model of mild chronic cold acclimatization at 8 řC, during which no damage to the heart or kidneys occurs and has proven cardioprotective effect on reducing infarct size. Hence, the influence of this cold acclimatization model on the other cellular and molecular processes needs to be investigated. The cardioprotective effect of cold acclimatization includes changes in β-AR signaling, activation of anti-apoptotic pathways or augmentation of the antioxidant system. The aim of this thesis was to investigate the effect of cold acclimation and subsequent reacclimation on proteins regulating Ca2+ levels in the rat heart (SERCA2 and phospholamban) and on the stimulation of regulatory proteins β-arrestin 1/2 and protein kinase PDPK1. The...
|
|
|
The effect of season on mitochondrial swelling of rat heart after cold acclimation
Kašík, Petr ; Horníková, Daniela (advisor) ; Holzerová, Kristýna (referee)
Risk of death from cardiovascular disease is substantially increased throughout winter season and by exposure of organism to acute cold stress. However, several studies have suggested that some cold acclimation models could act cardioprotectively. The thesis is focused on effects of acute and chronic cold acclimation on swelling of rat heart mitochondria. Mitochondrial swelling is, besides other things, caused by massive influx of Ca2+ into the mitochondria especially during ischemia-reperfusion injury. By that, mitochondria permeability transition pore is being opened and subsequently, this could end up in mitochondrial burst and cell death, eventually. Lower rate of mitochondrial swelling indicates greater mitochondrial resistance. The results express higher mitochondrial resistance after acute cold exposure and chronic cold acclimation. Key words: cold, mitochondria, Ca2+ ions, swelling, MPTP, myocardium, ROS, ischemia
|
|
|
Relationship between the renin-angiotensin-aldosterone system and the heart and its influence during 5°C cold acclimation.
Hlaváčová, Diana ; Horníková, Daniela (advisor) ; Heleš, Mário (referee)
Heart as one of the life-important organs is influenced by many ongoing processes in organism. Even the smallest molecular changes can importantly influence heart's physiology and activity. Last years, there were many studies concentrating on clarification of renin-angiotensin- aldosteron system (RAAS) and its influence on heart and kidneys. Cardiovascular diseases are usually caused by changes in RAAS and that is the reason why more and more experts are examining the extent to which diseases can be prevented and heart function improved. Ambient temperature is one of the factors that greatly affects the RAAS and the heart. In this thesis I tried to summarize current knowledge about RAAS and its effects on organism, focusing on influencing the physiology of the heart. While ambient temperature has significant effect on the RAAS and the heart, this thesis points to the knowledge associated with cold acclimation at 5 řC. Key words: renin-angiotensin-aldosteron system, heart, cold, hypertension, adrenergic receptors, natriuretic peptides
|
|
|
The role of uncoupling proteins (UCP) in cardioprotection
Furmánková, Tereza ; Horníková, Daniela (advisor) ; Adamcová, Kateřina (referee)
Cardiovascular disease (CVD) is the world's leading cause of death. Almost 18 million people die of CVD each year, and the prevalence continues to rise for both men and women. It is now clear that the maintenance of mitochondrial membrane potential can play an important role in the pathophysiology of the heart and it is involved in cardioprotective mechanisms. Mitochondrial membrane potential can be affected in a various of ways, one of them is the stimulation of uncoupling proteins. An elaboration of previous findings in this work has shown that uncoupling proteins have the effect of reducing oxygen radicals, inhibiting apoptosis, affect the production of ATP and atherosclerotic plaques and protect the heart from lipid toxicity. There are several ways to regulate their gene expression, and influencing these pathways may be a way to achieve cardioprotection. Key words: uncoupling proteins, mitochondria, cardioprtoection, thyroid hormones, fatty acids, adipose tissue, reactive oxygen species, FGF21
|
|
|
The role of cellular senescence in carcinogenesis and aging of the brain
Paroubková, Michaela ; Hodný, Zdeněk (advisor) ; Horníková, Daniela (referee)
The risk of developing many pathological conditions and ageing-releated diseases increases persistently throughout a lifetime. A dramatic increase in the number of people suffering from one of these diseases, such as atherosclerosis, Alzheimer's disease or Parkinson's disease, is caused by constant elevation of human life's length due to advancements in modern medicine and changes in life style. Several recent studies have demonstrated that senescent cells accumulate in aged and ill tissues. Senescent cells are metabolically active, but unable of proliferation and unlike the terminally differented cells, they secrete many factors that contribute to the transformation of the tissue microenviroment. The role of senescence as anticancer barier is known for a long time, but its importance in physiological processes and aging is mainly a matter of a recent time. While there is also a lot of studies focusing on cellular senescence in peripheral tissues, their involvement in or contribution to cognitive decline with aging of the central nervous system (CNS) remains relatively unknown. Recent data of many laboratories suggest that senescence-associated secretory phenotype of the non-neuronal senescent cells in brain can cause chronic level of inflammation and thus accompany aging and ageing-related...
|
|
|
Cellular senescence and ageing-associated diseases
Antoš, Šimon ; Hodný, Zdeněk (advisor) ; Horníková, Daniela (referee)
In the last years more evidence supports the role of cellular senescence in ageing-associated diseases. Cellular senescence plays a role in these diseases on multiple levels and often directly supports their pathogenesis. The goal of this bachelor thesis is to summarize latest knowledge regarding the mechanism and the efect cellular senescence has in ageing-associated diseases, namely cancer, atherosclerosis, osteoarthritis, neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease and multiple sclerosis, obesity and diabetes mellitus type two.
|
|
| |
|
|
The role of desmin in a heart
Šeovićová, Maja ; Horníková, Daniela (advisor) ; Vegrichtová, Markéta (referee)
Desmin forms a muscle specific intermediate filament which participates in a formation of a dynamic intracellular network that links contractile apparatus with a sarcolemma, mitochondria and it provides a communication with a cell nucleus. This network serves to maintain morphological and functional aspects of muscle cells and cell organelles during a muscle contraction. Mutation in a desmin or an absence of desmin is causing a serious disease called desminopathy, which belongs among a group of myofibrillar myopathies. This disease manifests itself in all muscle types, however first observable defects occur in cardiac mitochondria, thus heart is a first organ manifesting symptoms of this disease. The purpose of this thesis was to summarize a current knowledge about physiological and molecular mechanisms that involved in a formation of intracellular desmin network and about patho-physiological states of desminopathies. Key words: desmin, intermediate filaments, heart, desminopathy, cardiomyopathy
|
guest ::
