Application of rat cryptorchidism model for the evaluation of mesenchymal stromal cell secretome regenerative potential.

Male infertility represents a severe social and medical challenge. In recent years the progress in regenerative medicine promoted the development of novel options to overcome this medical condition. We are elaborating a promising approach to restore spermatogenesis using mesenchymal stromal cell (MSC) secretome components as a novel class of cell-free cell therapy medicinal products for regenerative medicine. However, the choice of the representative in vivo model of spermatogenesis failure to evaluate the effectiveness of regenerative drugs remains challenging. Using the rat model of bilateral abdominal cryptorchidism, we studied the contribution of MSC conditioned medium contained bioactive cell secreted products to the spermatogenesis recovery. The feasibility of this model to evaluate the drug-driven regenerative effects on spermatogenesis restoration after the injury was demonstrated. We revealed significant correlations between the extent of spermatogonial stem cell niche recovery, spermatozoa count and serum concentration of androgens as an indicator of Leydig cell function. The obtained results can be applied in preclinical studies to choose the proper criteria to appraise the specific activity of novel regenerative drugs developed for the treatment of non-obstructive spermatogenesis disorders.

Role of oxidative stress and mitochondria in onset of urinary bladder dysfunction under acute urine retention.

Acute urine retention is a frequent complication in patients with benign hyperplasia of the prostate gland. According to studies made on experimental animals and people, it is accompanied by the deterioration of the bladder blood supply. This study attempts to explore the relationship of intramural blood flow, production of reactive oxygen species, and functional state of the bladder detrusor in modeling of acute urine retention in rats, as well as the impact of mitochondria-targeted antioxidants (which are supposed to alleviate the effects of oxidative stress induced by experimental ischemia) on these parameters. The study showed beneficial effects of mitochondria-targeted antioxidant SkQR1 in preventing damage of the bladder caused by acute urinary retention, which suggests the therapeutic use of this type of compounds for the treatment of ischemic abnormalities of the urinary bladder.

Assessment of intramural blood flow and neurogenic control in intact and hypertrophic urinary bladder with harmonic analysis of bioimpedance in rats.

High-resolution impedancometry and harmonic (Fourier) analysis of variable component of bioimpedance revealed rhythmic oscillations of urinary bladder bioimpedance at the Mayer wave, respiration, and heartbeat frequencies. The power values of the corresponding Mayer, respiratory, and cardiac peaks were calculated to assess circulation in the urinary bladder wall and its autonomic nervous control at various stages of infusion cystometry in intact rats and in the rats with preliminary formed infravesical obstruction (IVO). In intact rats, filling of the bladder with physiological saline diminished the power of the first (fundamental) cardiac peak attesting to a decrease of the blood flow in the bladder wall. Simultaneously, the power of low-frequency Mayer peak reflecting sympathetic activity increased, while the power of respiratory peak decreased supposedly reflecting abatement of the parasympathetic influences. Bladder voiding was accompanied by a decrease of Mayer peak and increase of the respiratory one. Prior to infusion cystometry, the intravesical pressure in IVO rats was elevated while the power of fundamental cardiac peak was below the control value. Filling the bladder in these rats was accompanied by further decrease of the cardiac peak reflecting still greater drop in blood supply. In control rats, voiding the bladder normalized the vesical circulation assessed by the cardiac peak, while in IVO rats this peak remained decreased. The reciprocal changes of Mayer and respiratory peaks observed during infusion cystometry in the norm were replaced by unidirectional decrease in the power of both peaks in IVO rats, which probably attest to disturbance of autonomic nervous control in the hypertrophic urinary bladder in these rats.

Bioimpedance harmonic analysis as a tool to simultaneously assess circulation and nervous control.

Multicycle harmonic (Fourier) analysis of bioimpedance was employed to simultaneously assess circulation and neural activity in visceral (rat urinary bladder) and somatic (human finger) organs. The informative value of the first cardiac harmonic of the bladder impedance as an index of bladder circulation is demonstrated. The individual reactions of normal and obstructive bladders in response to infusion cystometry were recorded. The potency of multicycle harmonic analysis of bioimpedance to assess sympathetic and parasympathetic neural control in urinary bladder is discussed. In the human finger, bioimpedance harmonic analysis revealed three periodic components at the rate of the heart beat, respiration and Mayer wave (0.1 Hz), which were observed under normal conditions and during blood flow arrest in the hand. The revealed spectrum peaks were explained by the changes in systemic blood pressure and in regional vascular tone resulting from neural vasomotor control. During normal respiration and circulation, two side cardiac peaks were revealed in a bioimpedance amplitude spectrum, whose amplitude reflected the depth of amplitude respiratory modulation of the cardiac output. During normal breathing, the peaks corresponding to the second and third cardiac harmonics were split, reflecting frequency respiratory modulation of the heart rate. Multicycle harmonic analysis of bioimpedance is a novel potent tool to examine the interaction between the respiratory and cardiovascular system and to simultaneously assess regional circulation and neural influences in visceral and somatic organs.

Rhythmic oscillations of human penile bioimpedance in healthy individuals and in patients with vascular erectile dysfunction.

Small variations of electric impedance (bioimpedance) of human penis were examined in healthy volunteers and in patients with vascular erectile dysfunction (ED). The harmonic analysis revealed rhythmic oscillations of penile bioimpedance at frequencies corresponding to the heart and respiration rates and Mayer wave (0.1 Hz) and to multiple frequencies (harmonics) of the respiratory and cardiac oscillations. In normal penile bioimpedance spectrum, the Mayer and respiratory peaks were several times higher than the first cardiac (pulsatile) harmonic indicating neurogenic origin of rhythmic bioimpedance variations in the whole penis. The most of healthy individuals (78%) demonstrated the cardiac harmonics at the frequency range of 4-7 Hz that violated the monotone decrement of the pulsatile harmonic series suggesting the resonant character of oscillations of the penile arteries at this "near" frequency range. In contrast to stable 1-4 cardiac harmonics, the amplitudes of the near-range resonant harmonics could vary during few minutes suggesting a causal relation of the corresponding bioimpedance oscillations with the varying vascular tone in penile arteries. The most patients (89%) with vascular ED demonstrated not only the first 1-4 monotonically decrementing harmonics and the near-resonant ones, but also the stable cardiac harmonics at the "far" frequency range of 8-14 Hz that also disturbed the monotonic character of the cardiac harmonic series indicating the sclerotic alterations in regional arteries. In ED patients, insignificant decrease of the initial cardiac harmonics C1-C3 in comparison with the norm was accompanied by pronounced and significant decrease of the respiratory R1 and Mayer M1 peaks. The study showed that the far-frequency bioimpedance resonances at the range of 8-14 Hz and dramatic drop of Mayer and respiratory peaks are the diagnostic signs of vascular ED independent on the accompanying hormonal or neurogenic disorders.

Inhibition of GSK-3ß decreases the ischemia-induced death of renal cells.

Pharmacological preconditioning with insulin and lithium ions prevented the death of renal cells under conditions of ischemia/reperfusion. Preincubation of cells with insulin or lithium ions decreased production of reactive oxygen species after ischemia/reoxygenation. These agents also prevented the development of mitochondrial dysfunction in renal cells induced by ischemia/reoxygenation. It was hypothesized that the protective effects of these agents are related to inhibition of glycogen synthase kinase-3(. This enzyme is inactivated upon phosphorylation of serine residue in position 9. We found that in vivo administration of lithium ions to animals before renal ischemia prevents the development of kidney failure.

Comparative analysis of secretory and reabsorbing activity of ileal and sigmoid mucosa, employed for urinary bladder intestinoplasty.

In experiments on rats we studied reabsorption and secretory activity of the mucosa in isolated segments of the ileum and sigmoid colon used for urinary bladder intestinoplasty after cystectomy. Ileal mucosa was found to retain high metabolic activity under changed conditions. It reabsorbs urea, creatinine, potassium, sodium, chlorine, phosphorus, calcium, glucose, and uric acid from the urine and secretes magnesium, iron, and proteins into the urine. Sigmoid mucosa appeared to be less active in terms of reabsorption of the studied urine metabolites, but more actively secreted calcium and magnesium into urine and additionally secreted sodium. It was accompanied by an increase in blood concentrations of urea, creatinine, glucose, phosphorus, magnesium (only for sigmoid colon) and development of hypoproteinemia. These findings are important for investigation and prevention of metabolic complications after urinary bladder intestinoplasty.

Mitochondria-targeted plastoquinone derivatives as tools to interrupt execution of the aging program. 2. Treatment of some ROS- and age-related diseases (heart arrhythmia, heart infarctions, kidney ischemia, and stroke).

Effects of 10-(6'-plastoquinonyl) decyltriphenylphosphonium (SkQ1) and 10-(6'-plastoquinonyl) decylrhodamine 19 (SkQR1) on rat models of H2O2- and ischemia-induced heart arrhythmia, heart infarction, kidney ischemia, and stroke have been studied ex vivo and in vivo. In all the models listed, SkQ1 and/or SkQR1 showed pronounced protective effect. Supplementation of food with extremely low SkQ1 amount (down to 0.02 nmol SkQ1/kg per day for 3 weeks) was found to abolish the steady heart arrhythmia caused by perfusion of isolated rat heart with H2O2 or by ischemia/reperfusion. Higher SkQ1 (125-250 nmol/kg per day for 2-3 weeks) was found to decrease the heart infarction region induced by an in vivo ischemia/reperfusion and lowered the blood levels of lactate dehydrogenase and creatine kinase increasing as a result of ischemia/reperfusion. In single-kidney rats, ischemia/reperfusion of the kidney was shown to kill the majority of the animals in 2-4 days, whereas one injection of SkQ1 or SkQR1 (1 micromol/kg a day before ischemia) saved lives of almost all treated rats. Effect of SkQR1 was accompanied by decrease in ROS (reactive oxygen species) level in kidney cells as well as by partial or complete normalization of blood creatinine and of some other kidney-controlled parameters. On the other hand, this amount of SkQ1 (a SkQ derivative of lower membrane-penetrating ability than SkQR1) saved the life but failed to normalize ROS and creatinine levels. Such an effect indicates that death under conditions of partial kidney dysfunction is mediated by an organ of vital importance other than kidney, the organ in question being an SkQ1 target. In a model of compression brain ischemia/reperfusion, a single intraperitoneal injection of SkQR1 to a rat (1 micromol/kg a day before operation) effectively decreased the damaged brain area. SkQ1 was ineffective, most probably due to lower permeability of the blood-brain barrier to this compound.

The role of mitochondria in oxidative and nitrosative stress during ischemia/reperfusion in the rat kidney.

Reoxygenation following ischemia causes tissue oxidative stress. We studied the role of oxidative stress caused by kidney ischemia/reperfusion (I/R) on the mitochondria of renal tissue slices. I/R caused the mitochondria to be swollen, fragmented, and have lower membrane potential. The mitochondria generated more reactive oxygen species (ROS) and nitric oxide (NO) in situ as measured by fluorescence of ROS- and NO-sensitive probes. Infusion of lithium ion, an inhibitor of glycogen kinase synthase-3, caused phosphorylation of its Ser-9 and restored the membrane potential and decreased ROS production of the mitochondrial fraction. Ischemic kidney and hypoxic rat preconditioning improved mitochondrial membrane potential and lowered ROS production caused by subsequent I/R similar to lithium ion infusion. Preconditioning normalized NO production in mitochondria as well. The drop in the mitochondrial membrane potential was prevented by NO synthase inhibition, demonstrating a strong contribution of NO to changes in mitochondrial energy metabolism during the I/R transition. Mitochondria in the I/R-stressed kidney contained less cytochrome c and more pro-apoptotic Bax, consistent with apoptotic degradation.

Contractile function of upper urinary tract after indwelling ureteral prosthesis: experimental investigation.

BACKGROUND: Ureteral endoprostheses are used for dilatation of strictures in order to maintain upper urinary tract (UUT) function for a longer period. MATERIALS AND METHODS: Three kinds of short (3-4-cm) endoprostheses were inserted into the ureter of mongrel dogs with intact UUT or experimental ureter strictures. The UUT function was evaluated by means of radiographic examinations and in terms of following measures of contractility: intraluminal pressure, electroureterography (EUG), and multichannel impedance ureterography (MIUG). Studies were performed 1, 3 to 6 months, and 1 to 3 years after prostheses implantation. RESULTS: Similar urodynamic changes were registered in prosthetically treated ureters of dogs with initially intact UUTs and those with ureteral strictures. These disorders consisted of increased UUT intraluminal pressure and different functioning of the upper and lower regions of the ureter. The bioelectric and contractile activity of the upper UUT regions was reinforced, accelerated, and dysrhythmic, while peristaltic ureter wall function below the endoprosthesis was rare and weak. CONCLUSIONS: The changes observed are typical for ureteral prosthetics. The UUT urodynamic alterations could be attributable entirely to the excluding of the ureteral segment from active contraction and were the result of the local absence of the ureteral wall closing mechanism. One must keep in mind that UUT endoprostheses produce a high load on the ureter wall. The transition from UUT hyperfunction to contractile function decompensation may depend on the intrinsic compensatory reserves of the ureter.

Liposoluble vitamins E and A in human renal cortex and renal cell carcinomas.

Vitamin E was quantified in renal cell carcinomas (RCC) and in 'intact' renal cortex, obtained from 31 patients subjected either to unilateral nephrectomy or to partial resection of the only kidney. Histologically, 14 tumors consisted predominantly of clear cells (group 1) and 17 of other cell types (group 2). In both groups, a significant increase in vitamin E concentration, as compared to the 'intact' cortex, was observed: 167.8 +/- 27.9 and 68.2 +/- 15.2 micrograms/g wet tissue weight (mean +/- SEM) for groups 1 and 2, respectively, versus 10.1 +/- 0.53 micrograms/g wet tissue weight for the cortex. Although the total lipid content was also increased in tumors (especially in group 1), the vitamin E concentration in tumor tissue, calculated per milligram of total lipids, proved to be much higher in both groups than in 'intact' cortex. A significant positive correlation was observed between vitamin E and total lipid content in group 1 and 2 carcinomas. It was also found that vitamin E accumulation in RCC is unlikely to be attributed to an enhanced lipid deposit in the tumor cells. Thus, in 8 tumors of group 2 the vitamin E levels were markedly enhanced although these tumors did not differ from the cortex in total lipid concentrations. Vitamin A content determined in 17 carcinomas, when calculated per milligram of total lipids, was the same as in 'intact' cortex.