Martina Antosova

Expression of Ki-67, Bcl-2, Survivin and p53 Proteins in Patients with Pulmonary Carcinoma

Apoptosis is the fundamental process necessary for eliminating damaged or mutated cells. Alterations in the apoptotic pathway appear to be key events in cancer development and progression. Bcl-2 is the key member of the Bcl-2 family of apoptosis regulator proteins with anti-apoptotic effects. Survivin acts as an inhibitor of apoptosis as well and has been implicated in both inhibition of apoptosis and mitosis regulation. p53 is one of the tumor suppressor proteins, prevents tumor formation through cell cycle blocking and eliminates damaged cells via the activation of apoptosis. The Ki-67 protein is a cellular marker for proliferation. To investigate the possible interactions of the aforementioned proteins, we examined their expression in 76 patients with diagnosed lung cancer using immunohistochemical visualisation. Ki-67 protein was expressed in the cancer cells of all patients with small cell lung cancer (SCLC). We found a negative correlation between survivin and p53 expression. A decreased intensity of survivin expression and fewer cells positive for survivin (66.7%) in SCLC in comparison with other lung cancer types (98.0%) was detected. Reversely, expression of Bcl-2 was found in more than 90% of cases with SCLC. We hypothesize that high expression and intensity of Bcl-2 protein could be a factor behind a bad prognosis in SCLC.

Exhaled nitric oxide - circadian variations in healthy subjects

ObjectiveExhaled nitric oxide (eNO) has been suggested as a marker of airway inflammatory diseases. The level of eNO is influenced by many various factor including age, sex, menstrual cycle, exercise, food, drugs, etc. The aim of our study was to investigate a potential influence of circadian variation on eNO level in healthy subjects.MethodsMeasurements were performed in 44 women and 10 men, non-smokers, without respiratory tract infection in last 2 weeks. The eNO was detected at 4-hour intervals from 6 a.m. to 10 p.m. using an NIOX analyzer. We followed the ATS/ERS guidelines for eNO measurement and analysis.ResultsPeak of eNO levels were observed at 10 a.m. (11.1 ± 7.2 ppb), the lowest value was detected at 10 p.m. (10.0 ± 5.8 ppb). The difference was statistically significant (paired t-test, P < 0.001).ConclusionsThe daily variations in eNO, with the peak in the morning hours, could be of importance in clinical practice regarding the choice of optimal time for monitoring eNO in patients with respiratory disease.

Cardiac autonomic control in adolescents with primary hypertension

BackgroundImpairment in cardiovascular autonomic regulation participates in the onset and maintenance of primary hypertension.ObjectiveThe aim of the present study was to evaluate cardiac autonomic control using long-term heart rate variability (HRV) analysis in adolescents with primary hypertension.Subjects and methodsTwenty two adolescent patients with primary hypertension (5 girls/17 boys) aged 14-19 years and 22 healthy subjects matched for age and gender were enrolled. Two periods from 24-hour ECG recording were evaluated by HRV analysis: awake state and sleep. HRV analysis included spectral power in low frequency band (LF), in high frequency band (HF), and LF/HF ratio.ResultsIn awake state, adolescents with primary hypertension had lower HF and higher LF and LF/HF ratio. During sleep, HF was lower and LF/HF ratio was higher in patients with primary hypertension.ConclusionsA combination of sympathetic predominance and reduced vagal activity might represent a potential link between psychosocial factors and primary hypertension, associated with increased cardiovascular morbidity.

Competition of NO synthases and arginase in the airways hyperreactivity.

The competition between arginases and NO synthases (NOS) for their common substrate L-arginine can be important in the airways hyperreactivity. We investigated the effect of the simultaneous modulation of arginase and NOS activities in allergen-induced airways hyperreactivity. We analysed the response of tracheal and lung tissue smooth muscle to histamine or acetylcholine after administration N(ω)-nitro-L-arginine methyl ester (L-NAME), aminoguanidine (AG) and N(ω)-hydroxy-L-arginine (NOHA) in the combinations in in vitro conditions. The results show the decrease of ovalbumin-induced hyperreactivity after inhibition of arginase activity with NOHA. A supplementation of L-arginine caused favourable effect on the airway smooth muscle response. We found the airway reactivity decrease on the whole if we used the combination of NOS and arginase inhibitors. The inhibition of both types of enzymes caused more expressive effect in tracheal smooth muscles. We recorded the difference in the response to histamine or acetylcholine. The simultaneous inhibition of iNOS (with AG) and arginase (with NOHA) evoked the most expressive effect. Results show the importance of competition of both types enzymes - NOS and arginase for the balance of theirs activities in the control of airways bronchomotoric tone in the conditions of the airways hyperreactivity.

Study of the interaction of glutamatergic and nitrergic signalling in conditions of the experimental airways hyperreactivity

BACKGROUND Glutamatergic and nitrergic system participate in the control of respiratory system functions. It is only little information regarding a possible interaction of both systems in the airways hyperractivity. We investigated the effect of agents modulating the activity of these systems on the experimental ovalbumin-induced airways hyperreactivity as well as on the changes of exhaled nitric oxide (eNO) levels. METHODS We used the agonists of NMDA receptors - N-methyl-D-aspartic acid (NMDA) and monosodium glutamate (MSG), selective competitive antagonist (DL-2-amino-5-phosphonovaleric acid - AP-5) and selective non-competitive antagonist (dizocilpine - MK-801) of these receptors. We used also non-specific inhibitor of NO synthases N(ω)-nitro-L-arginine methyl ester (L-NAME). The airways responsiveness to histamine or acetylcholine was evaluated under in vitro conditions. RESULTS NMDA administration caused the increase of tracheal smooth muscle response in ovalbumin-induced hyperreactivity to acetylcholine. The effect of MSG was less pronounced. MK-801 as well as AP-5 provoked the decrease of reactivity mainly to acetylcholine in tracheal smooth muscle. We recorded the changes in eNO levels. The activation of NMDA receptor with NMDA or MSG increased eNO levels. The inhibition of NO synthase with L-NAME caused the fall of eNO levels. MK-801 shows (within the group) the more expressive effect in the eNO levels during sensitization than AP-5 group. CONCLUSION The results confirm the possibility of NMDA receptors participation in the experimental airways hyperreactivity.

The long-term administration of Orai 1 antagonist possesses antitussive, bronchodilatory and anti-inflammatory effects in experimental asthma model.

The best-studied store-operated Ca2+ channels (SOCs), Ca2+ release activated Ca2+ (CRAC) channels, are activated by depleting endoplasmic reticulum Ca2+ pool and mediate Ca2+ influx vitally important for Ca2+ restoration and many cellular function. CRAC channels were identified on immune and airway smooth muscle (ASM) cells. Emerging evidence points to its involvement in allergic airways diseases. This article evaluated therapeutic potency of CRAC antagonist in experimental animal model of allergic asthma. Allergic asthma, induced by repetitive exposure of guinea pigs to ovalbumine, was followed by 14 days therapy by CRAC antagonist (3-fluoropyridine-4-carboxylic acid, FPCA). In vivo changes of specific airways resistance (sRaw) evaluated bronchodilatory effect of FPCA and salbutamol. The method of citric acid-induced cough reflex assessed antitussive activity of FPCA and codeine. The measurement of exhaled NO (ENO), expression of inducible NO-synthase (iNOS) by RT-PCR and immunohistochemical staining of airways tissue verified anti-inflammatory effect of FPCA. Long-term administration of FPCA resulted in significant cough suppression and bronchodilation, both comparable to the effect of control drugs. FPCA significantly decreased ENO and iNOS expression, which together with immunohistochemical analysis validated its anti-inflammatory effect. Presented data confirmed CRAC channels as a promising target for treatment of respiratory diseases associated with allergic inflammation.

Glutamate receptors and the airways hyperreactivity.

It is proposed the link between the hyperactivity of NMDA receptors and airway hyperresponsiveness. We investigated the effect of agents modulating the activity of NMDA receptors in the ovalbumin-induced airway hyperreactivity in guinea pigs. The airways hyperreactivity was influenced by the agonist (NMDA) and selective antagonist - competitive (AP-5) and non-competitive (MK-801) of NMDA receptors. Airway responsiveness to histamine or acetylcholine was evaluated in in vitro conditions. NMDA administration caused the increase of tracheal smooth muscle response in ovalbumin-induced hyperreactivity to acetylcholine. MK 801 as well as AP-5 provoked the decrease of reactivity mainly to acetylcholine in tracheal smooth muscle, while the former, non-competitive antagonist was more effective. We recorded more pronounced response in tracheal than in lung tissue smooth muscle with more considerable response to acetylcholine than to histamine. The results of experiments show the modification of airway smooth muscles responses by agents modulating the activity of NMDA receptors. They confirm the possibility of NMDA receptors participation in experimental airway hyperreactivity. The results enlarge information regarding the link of the inflammatory diseases and glutamatergic system.

The influence of L-NAME on iNOS expression and markers of oxidative stress in allergen-induced airway hyperreactivity.

Nitric oxide (NO) effects in airways are influenced by the activity of NO-synthase isoforms and NO metabolism. Inducible NO-synthase (iNOS), which produces large amounts of NO, is active during the inflammatory process. NO quickly reacts, producing reactive oxygen species (ROS). In this study we attempted to detect the expression of iNOS and markers of ROS in the airway hyperreactivity (AHR) condition. The study was performed in guinea pigs, divided into four groups. Two groups were treated with the non-selective inhibitor of NO-synthase L-NAME. The other two groups were used as controls. Exhaled NO was monitored in vivo, AHR was assessed both in vivo and in vitro, and the expression of iNOS in lung homogenate, and oxidative stress markers were measured in the venous blood. L-NAME significantly affected the AHR only in in vitro condition, blocked the expression of iNOS in control but not in sensitized animals, and decreased the level of exhaled NO. The results concerning the oxidative stress markers are equivocal. The study confirmed that NO is involved in the regulation of AHR; the effects being mediated via iNOS and ROS activity.

Bidirectional link between upper and lower airways in patients with allergic rhinitis

ObjectiveExhaled nitric oxide has been proposed as a noninvasive marker of eosinophilic airway inflammation in lower airways. The aim of the study was to investigate the impact of atopy, pollen exposure, and pharmacological treatment on NO production in lower airways of patients with allergic rhinitis.Subjects and methodsMeasurements of exhaled NO were performed in 79 non-asthmatic subjects with seasonal allergic rhinitis outside and in pollen season, before and after pharmacological treatment, and in 54 healthy controls.ResultsPatients with allergic rhinitis had significantly higher levels of exhaled NO (18.3 ± 11.0 ppb) than healthy controls (13.0 ± 7.2 ppb) measured outside the pollen season (P = 0.0024). Increased exhaled NO levels were also found in patients with allergic rhinitis in the pollen season (27.0 ± 20.0 ppb) compared with the levels outside pollen season (P = 0.0001), before pharmacological treatment. In rhinitic patients treated by nasal corticosteroids and antihistamines in the pollen season, the levels of exhaled NO were significantly lower (17.0 ± 16.4 ppb; P = 0.045) than those before treatment. No difference was found in NO levels in rhinitic patients outside and in pollen season after pharmacological treatment.ConclusionsThis study has shown the presence of eosinophilic airway inflammation in the lower airways in allergic rhinitis patients. A significant increase of exhaled NO after pollen exposure in rhinitic patients underlies the impact of inflammation on the upper respiratory tract. A bidirectional link between upper and lower airways is confirmed by a decrease in exhaled NO in the pollen season, almost to the starting levels, after application of topic corticosteroids and antihistamines.

Pharmacologic modulation of experimentally induced allergic asthma.

Pharmacologic modulation of experimentally induced allergic asthma Allergic asthma is the most frequent disease of the respiratory tract. The aim of the current experimental and clinical studies was to find new sources of drugs able to control asthmatic inflammation and airway hyperresponsiveness. Our experimental studies were focused on efficiency evaluation of substances able to influence activities of ion channels, phosphodiesterase (PDE) isoforms, substances from the group of polyphenols and NO metabolism modulators during experimentally induced allergic asthma.