INDICATORS OF BONE METABOLISM IN PATIENTS WITH RHEUMATOID ARTHRITIS WITH IMPAIRED BONE MINERAL DENSITY: CHARACTERISTICS, THEIR FEATURES AND DIAGNOSTIC VALUE.

Rheumatoid arthritis (RA) is an autoimmune disease with a chronic inflammatory process that affects bone metabolism and leading to impaired bone mineral density (BMD). Therefore, the determination of laboratory markers of bone metabolism contributes to a better understanding of the pathogenesis of metabolic bone diseases. The aim of the study - to characterize the bone metabolism parameters in rheumatoid arthritis patients with impaired bone mineral density, to find out their features and diagnostic value. The study included 76 patients randomly stratified by RA status who were treated in the Rheumatology Department of Lviv Regional Clinical Hospital, a municipal non-profit enterprise of Lviv Regional Council, from 2013 to 2019. The goal was achieved by performing three consecutive stages of the study. At the first stage, markers of bone formation and bone resorption were characterized. At the second stage, the peculiarities of these indicators were determined. The third stage was to determine the diagnostic value of the content of the markers of OCN formation, P1NP and resorption marker ß-CrossLaps. According to the results of the study at the first stage, it was found that, in RA patients with osteopenia, the serum content of markers of osteoblastic bone function OCN (p=0.000) and P1NP (p=0.035) was significantly lower compared to the healthy individuals of CG, while the content of the marker of bone resorption ß-CrossLaps was significantly higher (p=0. 021); in RA patients with OP, the serum content of both markers of osteoblastic bone function OCN (p=0.000) and P1NP (p=0.001) is significantly lower, while ß-CrossLaps (p>0.050) is only slightly higher compared to healthy CG subjects. According to the results obtained at the second stage of the study, it can be stated that the content of OCN and P1NP in the blood serum is significantly lower in RA patients both with osteopenia and OP compared to RA patients without BMD disorders. At the third stage of the study, it was found significant relationship between the content of P1NP and belonging to SG1 (AC -0.52). A confirmed relationship was found between the content of OCN and belonging to the group with OP (direct direction of AC 0.57; p=0.017). Bone structure disorders in rheumatoid arthritis patients with osteopenia are characterized by a weakening of bone formation and increased resorption processes; in rheumatoid arthritis patients with osteoporosis, the weakening of osteoblastic bone function is more pronounced compared to rheumatoid arthritis patients with osteopenia. For rheumatoid arthritis patients with unimpaired bone mineral density, the highest diagnostic value is provided by procollagen type I N-terminal propeptide. For rheumatoid arthritis patients with osteoporosis, osteocalcin is a diagnostically valuable marker.

Age-Dependent Effects of Remote Preconditioning in Hypertensive Rat Hearts are Associated With Activation of RISK Signaling.

Remote ischemic preconditioning (RIPC) represents one of the forms of innate cardioprotection. While being effective in animal models, its application in humans has not been always beneficial, which might be attributed to the presence of various comorbidities, such as hypertension, or being related to the confounding factors, such as patients' sex and age. RIPC has been shown to mediate its cardioprotective effects through the activation of Reperfusion Injury Salvage Kinase (RISK) pathway in healthy animals, however, scarce evidence supports this effect of RIPC in the hearts of spontaneously hypertensive (SHR) rats, in particular, in relationship with aging. The study aimed to investigate the effectiveness of RIPC in male SHR rats of different age and to evaluate the role of RISK pathway in the effect of RIPC on cardiac ischemic tolerance. RIPC was performed using three cycles of inflation/deflation of the pressure cuff placed on the hind limb of anesthetized rats aged three, five and eight months. Subsequently, hearts were excised, Langendorff-perfused and exposed to 30-min global ischemia and 2-h reperfusion. Infarct-sparing and antiarrhythmic effects of RIPC were observed only in three and five months-old animals but not in eight months-old rats. Beneficial effects of RIPC were associated with increased activity of RISK and decreased apoptotic signaling only in three and five months-old animals. In conclusion, RIPC showed cardioprotective effects in SHR rats that were partially age-dependent and might be attributed to the differences in the activation of RISK pathway and various aspects of ischemia/reperfusion injury in aging animals.

CRITERIA FOR DIAGNOSIS OF CARDIOMYOPATHY IN PATIENTS WITH ALCOHOLIC LIVER CIRRHOSIS BEFORE THE ONSET OF HEART DAMAGE CLINICAL SIGNS.

The article clarifies the diagnostic criteria for syntropic heart damage - cardiomyopathy in patients with Alcoholic Liver Cirrhosis before the clinical signs of heart damage appear. As a result of the examination of 64 patients with Cirrhotic Cardiomyopathy, of which 51 patients were identified without clinical signs of heart damage (study group 1), 13 patients with clinical signsof heart damage (study group 2), and 23 patients without cardiomyopathy (comparison group), it was found that: 1) in patients with Cirrhotic Cardiomyopathy (both with and without manifestation of clinical signs of heart damage), there is a violation of its diastolic and systolic functions, which can be diagnosed by change of parameters of the natriuretic peptide in the blood plasma, the frequency of supraventricular premature beats and premature ventricular contractions, the duration of the QT interval, the maximum blood flow velocity in the phase of early filling of the left ventricle and the left atrium systole, their ratio, the myocardial functional capacity index, end-diastolic and end-systolic volumes of the left ventricle and left atrium; 2) in patients with Cirrhotic Cardiomyopathy without clinical manifestations, significantly lower (p<0.05) indicators of the natriuretic peptide, the frequency ofextrasystoles, the end-diastolic and end-systolic volumes of the left ventricle and left atrium, and a higher rate of ejection fraction of the left ventricle were revealed than in patients with the clinical manifestation of this disease; 3) we found high accuracy, specificity and sensitivity of the indicators of the natriuretic peptide, the QT interval (maximum, maximum corrected, average, mid-corrected), maximum blood flow velocity in the phase of early filling of the left ventricle and of the systole of the left atrium, their ratio, as well as the myocardial functional capacity index in patients with alcoholic liver cirrhosis with an asymptomatic course of cardiomyopathy that allows to use them to verify the diagnosis of Cirrhotic Cardiomyopathy until the first clinical signs of myocardial damage appear.

Hypercholesterolemia antagonized heart adaptation and functional remodeling of the mitochondria observed in acute diabetes mellitus subjected to ischemia/reperfusion injury.

Intrinsic cardioprotective mechanisms become activated in the early diabetes mellitus (DM) and this may protect the heart from ischemia/reperfusion (I/R) similarly as in case of ischemic preconditioning. However, this protection may by blunted in the presence of cardiovascular risk factors. Assuming that hypercholesterolemia (HCH) frequently accompanies DM, this study extends findings from separate models of DM and HCH by investigation the impact of HCH on DM-induced changes, including those of compensatory nature, in rat heart and its mitochondria. We used a factorial design with all combinations of treatment factors DM and HCH: control rats (C) and streptozotocin-treated rats (DM), both on standard chow (C and DM) and fed fat-cholesterol diet (HCH and DM-HCH). Isolated, Langendorff perfused hearts were subjected to 30 min global ischemia followed by reperfusion. Significantly increased levels of cholesterol in DM-HCH after I/R injury abrogated compensatory fluidization characteristic of DM mitochondria membranes. Concomitantly, the mitochondrial Mg2+-ATPase activity in DM-HCH was depressed. In comparison with DM, which showed significantly reduced size of myocardial infarction with simultaneously improved recovery of contractile function due to conditioning, DM-HCH hearts exhibited attenuated resistance to I/R injury. Taken together, cholesterol-enriched diet was associated with inflicting damage and has been implicated in the mechanisms leading to suppression of cardiac protection presented in diabetic group. Apparently, DM and HCH are factors which are not additive in their effects, therefore, caution should be exercised, when interpreting findings from studies considering these factors in isolation. Our findings suggest that this complex condition could accelerate the development of late diabetic complications.

CHARACTER AND FREQUENCY OF THE VARIATIONS OF CO- AND POLYMORBID SYNTROPIC EXTRAHEPATIC LESIONS AND THEIR DEPENDENCE ON THE HEPATOPULMONARY SYNDROME SEVERITY DEGREE IN CIRRHOTIC PATIENTS.

In this study, we comprehensively examined 93 patients with liver cirrhosis, selected in a randomized manner, with the preliminary stratification by the presence of hepatopulmonary syndrome with the aim to study the nature and frequency of extrahepatic syntropic lesions of organs and systems and their dependence on the severity of lung injury that is necessary for the appointment of the most effective individualized comprehensive treatment. The results of our calculations showed that with the increasing of the hepatopulmonary syndromeseverity degree, the nature and the frequency of the syntropic co- and polymorbid functional and organic extrahepatic lesions of the organs and body systems was significantly (p<0.05) changing. Also some polymorbid disorders' combinations and/or combined variants of the syndromes and nosologies have been increasing in case of growing the severity of the hepatopulmonary syndrome, that shows their significant (p<0.05) dependency.

Cardioprotection induced by remote ischemic preconditioning preserves the mitochondrial respiratory function in acute diabetic myocardium.

A 2×2 factorial design was used to evaluate possible preservation of mitochondrial functions in two cardioprotective experimental models, remote ischemic preconditioning and streptozotocin-induced diabetes mellitus, and their interaction during ischemia/reperfusion injury (I/R) of the heart. Male Wistar rats were randomly allocated into four groups: control (C), streptozotocin-induced diabetic (DM), preconditioned (RPC) and preconditioned streptozotocin-induced diabetic (DM+RPC). RPC was conducted by 3 cycles of 5-min hind-limb ischemia and 5-min reperfusion. DM was induced by a single dose of 65 mg/kg streptozotocin. Isolated hearts were exposed to ischemia/reperfusion test according to Langendorff. Thereafter mitochondria were isolated and the mitochondrial respiration was measured. Additionally, the ATP synthase activity measurements on the same preparations were done. Animals of all groups subjected to I/R exhibited a decreased state 3 respiration with the least change noted in DM+RPC group associated with no significant changes in state 2 respiration. In RPC, DM and DM+RPC group, no significant changes in the activity of ATP synthase were observed after I/R injury. These results suggest that the endogenous protective mechanisms of RPC and DM do preserve the mitochondrial function in heart when they act in combination.

Stimulation of mitochondrial ATP synthase activity - a new diazoxide-mediated mechanism of cardioprotection.

Pharmacological preconditioning by diazoxide and a model of experimental streptozotocin-induced acute diabetes mellitus (STZ-DM) provided similar levels of cardioprotection assessed as limiting myocardial infarct size. The aim was to explore the possibility of existence of another in vitro mechanism, which could be contributory to cardioprotection mediated by diazoxide treatment. Mitochondrial membrane fluidity and ATP synthase activity in isolated heart mitochondria were determined under the influence of two factors, STZ-DM condition and treatment with diazoxide. Both factors independently increased the ATP synthase activity (p<0.05), as no interaction effect was observed upon the combination of STZ-DM with diazoxide. On the other hand, the mitochondrial membrane fluidity was significantly increased by STZ-DM only; no significant main effect for diazoxide was found. Based on the results from measurements of enzyme kinetics, we assume a direct interaction of diazoxide with the molecule of ATP synthase stimulated its activity by noncompetitive activation. Our present work revealed, for the first time, that cardioprotection induced by diazoxide may not be caused exclusively by mitochondrial K(ATP) opening, but presumably also by a direct interaction of diazoxide with ATP synthase, although the mechanisms for achieving this activation cannot be fully delineated.

Participation of heart mitochondria in myocardial protection against ischemia/reperfusion injury: benefit effects of short-term adaptation processes.

Acute streptozotocin diabetes mellitus (DM) as well as remote ischemic preconditioning (RPC) has shown a favorable effect on the postischemic-reperfusion function of the myocardium. Cardioprotective mechanisms offered by these experimental models involve the mitochondria with the changes in functional properties of membrane as the end-effector. The aim was to find out whether separate effects of RPC and DM would stimulate the mechanisms of cardioprotection to a maximal level or whether RPC and DM conditions would cooperate in stimulation of cardioprotection. Experiments were performed on male Wistar rats divided into groups: control, DM, RPC and DM treated by RPC (RPC+DM). RPC protocol of 3 cycles of 5-min hind limb ischemia followed by 5-min reperfusion was used. Ischemic-reperfusion injury was induced by 30-min ischemia followed by 40-min reperfusion of the hearts in Langendorff mode. Mitochondria were isolated by differential centrifugation, infarct size assessed by staining with 1 % 2,3,5-triphenyltetrazolium chloride, mitochondrial membrane fluidity with a fluorescent probe DPH, CoQ(9) and CoQ(10) with HPLC. Results revealed that RPC as well as DM decreased the infarct size and preserved mitochondrial function by increasing the mitochondrial membrane fluidity. Both used models separately offered a sufficient protection against ischemic-reperfusion injury without an additive effect of their combination.

Remote ischemic preconditioning of the heart: protective responses in functional and biophysical properties of cardiac mitochondria.

UNLABELLED: Remote ischemic preconditioning (RIP)-induced protection of myocardial energetics was well documented on the level of tissue, but data concerning the involvement of mitochondria were missing. We aimed at the identification of changes in membrane properties and respiratory functions induced in rat heart mitochondria by RIP. Experiments were performed on 46 male Wistar rats divided into control and RIP-treated groups of 21 animals each. Blood flow in the occluded area was recorded by MRI angiography in four animals. RIP protocol comprised of three successive 5-min occlusions each followed by 5-min reperfusions of descending branches of the right hind limb femoral artery. The efficacy of RIP was evaluated as the extent of RIP-induced protection against damage to the functions of mitochondria isolated by differential centrifugation after 30-min global ischemia followed by 40-min reperfusion of the hearts in Langendorff mode. ASSESSMENTS: mitochondrial membrane fluidity with a fluorescent probe DPH, CoQ(9) and CoQ(10) with HPLC, mitochondrial respiration with the Oxygraph-2k (Oroboros). Results revealed that RIP was affecting the mitochondria. The immediate protection conferred by RIP involves beneficial and prognostically significant effects: a total elimination of ischemia/reperfusion-induced depression of mitochondrial membrane fluidity and a trend for better preservation of mitochondrial state 3 respiration.

Treatment of rats with hypolipidemic compound pirinixic acid protects their hearts against ischemic injury: are mitochondrial K(ATP) channels and reactive oxygen species involved?

Hypolipidemic compound pirinixic acid (WY-14643, WY) is known to exert pleiotropic (other than primary) effects, such as activation of peroxisome proliferator-activated receptors (PPAR-alpha), transcription factors regulating different cardiac functions. Their role in ischemia-reperfusion (I/R) injury and cardioprotection is less clear, although protective effects of PPAR agonists have been documented. This study was designed to explore the effects of WY on the I/R injury in the rat heart and potential mechanisms involved, including mitochondrial K(ATP) channels (mitoK(ATP)) opening and production of reactive oxygen species (ROS). Langendorff-perfused hearts of rats intragastrally treated with WY (3 mg/kg/day) for 5 days and of control animals were subjected to 30-min global ischemia and 2-h reperfusion with or without 15-min perfusion with mitoK(ATP) blocker 5-hydroxydecanoate (5-HD) prior to I/R. Evaluation of the infarct size (IS, TTC staining) served as the main end-point of protection. Lipid peroxidation (a marker of ROS production) was determined by measurement of myocardial concentration of conjugated dienes (CD), whereas protein expression of endothelial NO synthase was analysed by Western blotting. A 2-fold increase in the cardiac protein levels of eNOS after treatment with WY was accompanied by lower post-I/R levels of CD compared with those in the hearts of untreated controls, although WY itself enhanced ROS generation prior to ischemia. IS was reduced by 47 % in the hearts of WY-treated rats (P<0.05), and this effect was reversed by 5-HD. Results suggest that PPAR-alpha activation may confer protection against lethal I/R injury in the rat heart that involves up-regulation of eNOS, mitoK(ATP) opening and reduced oxidative stress during I/R.

[New possibilities of Doppler flowmetric ultrasound diagnosis of portal hypertension complicated with varicose veins of the esophagus and bleeding prediction].

Liver cirrhosis as a stage in chronic diffuse liver diseases development manifests itself in structural remodeling of parenchyma and appearance of the main syndrome--portal hypertension. In turn it leads to hemorrhage in 54,3% with death rate of 30-50%. In the article research of hemodynamics in abdominal vessels by the means of modified sonographic Doppler flowmetry and prognosis of high risk esophageal varices are described. On the basis of statistical dependency between degree of esophageal varices, cirrhotic gastropathy and results of modified protocol close correlation is shown, which allow to recommend them as alternative in non-invasive diagnosis of liver cirrhosis complications.

[Characteristics of the autonomic nervous system in patients with liver cirrhosis].

Investigation of autonomic nervous system state was realized in 98 cirrhotic patients. Learned correlating connections between indexes of heart rhythm variability and difficulty of liver cirrhosis according to Child-Pugh let us elaborate criteria of difficulty stage of vegetative disorders and form a computerized program "Hepatovega".

Involvement of membrane fluidity in endogenous protective processes running on subcellular membrane systems of the rat heart.

Membrane fluidity is a widely recognized biophysical variable that provides information about structural organization of the subcellular membranes exhibiting physical characteristics of liquid crystals. The term "fluidity" reflects in this case the tightness in packing of acyl parts of the membrane phospholipid molecules, a feature that may influence considerably the molecular mobility and via that also the sensitivity and reactivity of membrane-bound transporters, receptors and enzyme systems. Data presented in this review are aimed to demonstrate the substantial role of changes in membrane fluidity occurring in the processes associated with endogenous protection observed in cardiac sarcolemma and mitochondria in diverse pathologies, particularly in diabetes and hypertension.

Dual influence of spontaneous hypertension on membrane properties and ATP production in heart and kidney mitochondria in rat: effect of captopril and nifedipine, adaptation and dysadaptation.

This study deals with changes, induced by hypertension and its treatment, in the function and properties of mitochondria in the heart and kidneys. Male, 16-week-old hypertensive rats were allocated to 3 groups: (i) animals treated daily for 4 weeks with captopril (CAP, 80 mg·(kg body mass)(-1), n = 45), (ii) animals treated with CAP + nifedipine (NIF, 10 mg·kg(-1), n = 45), or (iii) untreated hypertensive controls (n = 96). Wistar rats (n = 96) were used as normotensive controls. Systolic blood pressure (SBP), heart rate (HR), and heart mass / body mass (HW/BW) ratio were measured at the beginning and end of the experiments; measurements for mitochondrial Mg(2+)-ATPase activity, O(2)-consumption (QO(2)), respiratory control index (RCI), ADP/O, oxidative phosphorylation rate (OPR), conjugated diene content (CD), and membrane fluidity (MF) were also taken at different time intervals. In the heart, elevated SBP, HR, and HW/BW accompanied increased QO(2), OPR, and Mg(2+)-ATPase activity, indicating an adaptive response to hypertension-induced increase in the energy demands of the myocardium. Treatments with CAP or with CAP + NIF were very similar in their prevention of increase in SBP, HR, HW/BW, and the rise in OPR (all p < 0.05-0.01). In the kidneys, hypertension induced a drop in OPR; however, antihypertensive therapy aggravated the resulting energy deficiency, whereby treatment with CAP + NIF was more detrimental than treatment with CAP alone. Heart and kidney mitochondria exhibited negligible changes in CD and moderately increased MF, which was more potentiated by treatment with CAP alone than with CAP + NIF.

Seasonal variations in properties of healthy and diabetic rat heart mitochondria: Mg2+-ATPase activity, content of conjugated dienes and membrane fluidity.

Our previous preliminary results pointed to possible seasonal variations in Mg2+-ATPase activity of rat heart mitochondria (MIT). It is not too surprising since seasonal differences were already reported in myocardial function, metabolism and ultrastructure of the intact as well as hemodynamically overloaded rabbit hearts and also in other tissues. The present study is aimed to elucidate whether seasonal differences observed in rat heart MIT Mg2+-ATPase activity will be accompanied with changes in membrane fluidity and in the content of conjugated dienes (CD) in the lipid bilayers of MIT membranes as well as whether the above seasonal differences will also be present in the diabetic heart. Our results revealed that values of Mg2+-ATPase activity in the winter/spring-period (W/S-P) exceeded significantly (p<0.05-0.001) those in the summer/autumn-period (S/A-P). Similar trend was also observed in hearts of animals with acute (8 days) streptozotocin diabetes. With the exception of values of CD in the S/A-P, all values of Mg2+-ATPase activities, membrane fluidity and CD concentrations in diabetic hearts exceeded those observed in the healthy hearts. Our results indicate that seasonal differences may play a decisive role in the evaluation of properties and function of rat heart MIT.

Endogenous protective mechanisms in remodeling of rat heart mitochondrial membranes in the acute phase of streptozotocin-induced diabetes.

The aim of present study was to investigate functional and physical alterations in membranes of heart mitochondria that are associated with remodeling of these organelles in acute phase of streptozotocin-induced diabetes and to elucidate the role of these changes in adaptation of the heart to acute streptozotocin-induced diabetes (evaluated 8 days after single dose streptozotocin application to male Wistar rats). Action of free radicals on the respiratory chain of diabetic-heart mitochondria was manifested by 17 % increase (p<0.05) in oxidized form of the coenzyme Q(10) and resulted in a decrease of states S3 and S4 respiration, the respiratory control index, rate of phosphorylation (all p<0.01) and the mitochondrial transmembrane potential (p<0.05), but the ADP/O ratio decreased only moderately (p>0.05). On the contrary, membrane fluidity and the total mitochondrial Mg2+-ATPase activity increased (both p<0.05). In diabetic heart mitochondria, linear regression analysis revealed a reciprocal relationship between the increase in membrane fluidity and decrease in trans-membrane potential (p<0.05, r = 0.67). Changes in membrane fluidity, transmembrane potential, Mg2+-ATPase activity and the almost preserved ADP/O ratio appear as the manifestation of endogenous protective mechanisms participating in the functional remodeling of mitochondria which contributes to adaptation of the heart to diabetes.

Functional remodeling of heart mitochondria in acute diabetes: interrelationships between damage, endogenous protection and adaptation.

Rats with streptozotocin-diabetes develop mechanisms of endogenous protection (MEP) that participate actively in functional remodeling of cardiac sarcolemma. Remodeling of sarcolemma is a sign of damage but it also protects the cells of the diabetic heart (DH) against additional energy disbalance due to excessive Ca(2+) entry. Since yet, cardiac mitochondria (MIT) were investigated predominantly from the aspect of damage only. Aims of the present study were: i) to distinguish between acute diabetes-induced changes in function of rat heart MIT which clearly belong to damage from those that reflect the MEP and participate in functional remodeling of the MIT; ii) elucidate the significance of MEP-induced changes in heart MIT for cardiac energetics. Acute diabetes (8 days) was induced in adult male Wistar rats by streptozotocin (STZ, 65 mg.kg(-1) i.p., single dose). On the day 8 after STZ administration, the diabetic animals exhibited 300-330 % increase in blood glucose, triacylglycerols and cholesterol as well as 89.6 % increase in glycohemoglobin (all p < 0.01). The blood level of insulin dropped by 53 % (p < 0.02). State 3 and state 4 oxygen consumptions of DH MIT were decreased against the controls, leading to drop of the respiratory control index (17.9 and 7.3 %) and oxidative phosphorylation rate (OPR, 27.5 and 24.6 %; all p < 0.003-0.02). These effects of damage yielding in strained energy balance of the acute DH were partially alleviated by MEP. The latter involved temporary preservation of the ADP : O ratio, with participation of elevated MIT Mg(2+)-ATPase activity as well as increased formation of MIT substrate and energy transition pores (both p < 0.05). Hence, the energy disbalance of the acute DH was finally manifested in 13 % loss in its AMP content only (p < 0.05). Results indicate that MIT in STZ-DH are functionally remodeled. Defective O2 consumption by MIT renders molecular changes suggestive of a mild hypoxic state but an increase in Mg(2+)-ATPase activity and facilitated energy delivery from MIT to the cytoplasm indicate the presence of MEP acting in the MIT and alleviating the effect of decreased oxidative energy production in the acute DH.