Angiotensin 1-7 formation in breast tissue is attenuated in breast cancer - a study on the metabolism of angiotensinogen in breast cancer cell lines

The tissue renin-angiotensin system (RAS) plays an important role in the development and progression of many diseases. It has been confirmed that angiotensin II (ANG II) participates in the proliferation and angiogenesis of breast cancer. Moreover, some RAS dysregulations in cancer have been observed. Recent studies on the role of two opposite axes of angiotensinogen metabolism - ACE (angiotensin-converting enzyme)/ANGII/AT1R (angiotensin receptor type 1) and ACE-2/ANG 1-7/MAS (mitochondrial assembly) - indicate their importance in tumor growth and invasion, but studies describing the metabolic pathways in breast cancer and the role of newer angiotensins, such as ANG 1-12, remain lacking. In this study, the metabolism of angiotensinogen fragments in three breast cancer lines, namely, MDA-MB-231, MCF-7, and T-47D, compared with normal breast tissue cells (PCS-600) was estimated. Incubation of the cancer cells with angiotensinogen resulted in the prevalent formation of ANG 1-7. A difference in the ability to form ANG II was observed between cell lines. In normal breast cells, the strong predominance of the ACE-2/ANG 1-7/MAS pathway was detected. In cancer cells, differences in angiotensinogen metabolism depending on cancer line were observed; the prevalence of the ACE/ANG II/AT1R pathway was shown. Expressions of the RAS component were dysregulated in cancer cells and differed between cell lines. In conclusion, the ability of breast cancer cells to produce numerous angiotensin peptide metabolites was demonstrated. The metabolism of angiotensinogen differed between various types of breast cancer cells. The obtained results indicate the greater importance of the classical pathway - ACE/ANG II/AT1R - in breast cancer cells. The production of ANG 1-12 seems to be marginal in breast tissue, but a tendency for the higher formation of this peptide in cancer cells was observed. The production of ANG 1-7 was significantly lower in cancer cells, whereas the expression of MAS receptor was higher than that in the control. This finding suggests that substances with MAS receptor agonist activity could be useful in the treatment of breast cancer, but this requires further investigations.

Perindoprilat changes ANG (1-9) production in renal arteries isolated from young spontaneously hypertensive rats after ANG I incubation

We used mass spectrometry to quantitate production of angiotensinogen metabolites in renal artery of 3- and 7-month-old Wistar-Kyoto (WKY) and Spontaneously Hypertensive Rats (SHR). Tissue fragments were incubated for 15 min in oxygenated buffer, with added angiotensin I. Concentrations of angiotensins I (ANG I), II (ANG II), III (ANG III), IV (ANG IV), angiotensin (1-9) [ANG (1-9)], angiotensin (1-7) [ANG (1-7)], and angiotensin (1-5) [ANG (1-5)], excreted into the buffer during experiment, were measured using liquid chromatography-mass spectrometry (LC/MS) and expressed per mg of dry tissue. Effects of pretreatment with 10 microM perindoprilat on the production of ANG I metabolites were quantitated. Background production of any of ANG I metabolites differed neither between WKY and SHR rats nor between 3- and 7-month-old rats. Perindoprilat pretreatment of renal arteries resulted, as expected, in decrease of ANG II production. However, renal arteries of 7-month-old SHR rats were resistant to ACE inhibitor and did not change ANG II production in response to perindoprilat. In renal arteries, taken from 3-month-old rats, pretreated with perindoprilat, incubation with ANG I, resulted in the level of ANG (1-9) significantly higher in SHR than WKY rats. Our conclusion is that in SHR rats, sensitivity of renal artery ACE to perindoprilat inhibition changes with age.

The renin-angiotensin system and its vasoactive metabolite angiotensin-(1-7) in the mechanism of the healing of preexisting gastric ulcers. The involvement of Mas receptors, nitric oxide, prostaglandins and proinflammatory cytokines

The inhibition of angiotensin-converting enzyme (ACE) or the blockade of angiotensin (Ang) AT-1 receptors affords protection against acute gastric mucosal injury, but whether the major metabolite of renin-angiotensin system (RAS), Ang-(1-7), accelerates the healing process of preexisting gastric ulcers remains unknown. Previous studies documented that Ang-(1-7) acting via its own Mas receptor exerts vascular responses opposing those of Ang II. We studied the effects of the Ang-(1-7)/Mas receptor axis on the healing rate of acetic-acid-induced gastric ulcers with or without the blockade of Mas receptors by A 779 and compared it with the effects of activation and blockade of the AT-1 receptor by the treatment with Ang II and losartan, respectively, the inhibition of ACE by lisinopril, the NO/cNOS inhibition by L-NAME and inhibition of prostaglandin/COX system by indomethacin in the presence of Ang-(1-7). Additionally, ex vivo metabolism of Ang I in gastric tissue was assessed by LC/MS method. At day 9 after ulcer induction, the area of these ulcers and the accompanying changes in total gastric blood flow (GBF) were determined as were gastric mucosal blood flow (GMBF) at ulcer margin and gastric oxygen uptake (GVO2). The gastric mucosal expression of mRNAs for constitutive nitric oxide synthase (cNOS), superoxide dismutase (SOD), and pro-inflammatory cytokines interleukin 1β (IL-1β) and tumor necrosis factor alpha (TNF-α) and plasma level of both cytokines were determined by RT-PCR and ELISA. The 9 days treatment with Ang II dose-dependently increased the area of gastric ulcers and this effect was accompanied by a significant fall in the GBF, GVO2 and GMBF at ulcer margin. In contrast, treatment with Ang-(1-7) which produced a significant rise in the luminal content of NO significantly reduced the area of gastric ulcer and significantly increased the GBF, GVO2 and the GMBF at ulcer margin. Similar GMBF changes and significant reduction the area of gastric ulcer was observed in rats with gastric ulcers treated with the agonist of Mas receptor, AVE 0991. These effects of Ang-(1-7) and AVE 0991 were eliminated by blockade of the Mas receptor with A779. Similarly to Ang-(1-7), treatment with losartan or lisinopril significantly reduced the area of gastric ulcers and the accompanying increase in the GMBF at ulcer margin and these effects were significantly attenuated by a concomitant administration of L-NAME and indomethacin. The rate of healing of ulcers was associated with a decrease in ex vivo Ang-(1-7) formation and this effect was attenuated by lisinopril. The treatment with Ang-(1- 7) or AVE 0991 increased the expression of mRNA for cNOS and SOD and downregulated that of IL-1β and TNF-α followed by the decrease in the plasma IL-1β and TNF-α levels. We conclude that the Ang-(1-7)/Mas receptor system accelerates the healing of preexisting gastric ulcers via an increase in the gastric macro- and microcirculations, and an increase in gastric tissue oxygenation. These effects are mediated by PG and NO derived from overexpression of cNOS, an increase in the expression of antioxidizing enzyme SOD 2 and an anti-inflammatory action involving the inhibition of expression and release of pro-inflammatory cytokines IL-1β and TNF-α. Our results seem to underlie the importance of the Ang-(1-7), AT-1 and Mas receptors in the regulation of local vascular and metabolic effects associated with mechanism of gastric ulcer healing.

Exogenous Angiotensin I Metabolism in Aorta Isolated from Streptozotocin Treated Diabetic Rats

Purpose. Products of angiotensin (ANG) I metabolism may predispose to vascular complications of diabetes mellitus. Methods. Diabetes was induced with streptozotocin (75 mg/kg i.p.). Rat aorta fragments, isolated 4 weeks later, were pretreated with perindoprilat (3 μM), thiorphan (3 μM), or vehicle and incubated for 15 minutes with ANG I (1 μM). Products of ANG I metabolism through classical (ANG II, ANG III, and ANG IV) and alternative (ANG (1-9), ANG (1-7), and ANG (1-5)) pathways were measured in the buffer, using liquid chromatography-mass spectrometry. Results. Incubation with ANG I resulted in higher concentration of ANG II (P = 0.02, vehicle pretreatment) and lower of ANG (1-9) (P = 0.048, perindoprilat pretreatment) in diabetes. Preference for the classical pathway is suggested by higher ANG III/ANG (1-7) ratios in vehicle (P = 0.03), perindoprilat (P = 0.02), and thiorphan pretreated (P = 0.02) diabetic rat. Within the classical pathway, ratios of ANG IV/ANG II (P = 0.01) and of ANG IV/ANG III (P = 0.049), but not of ANG III/ANG II are lower in diabetes. Conclusions. Diabetes in rats led to preference toward deleterious (ANG II, ANG III) over protective (ANG IV, ANG (1-9), and ANG (1-7)) ANG I metabolites.

The influence of angiotensin-(1-7) peptidomimetic (AVE 0991) and nebivolol on angiotensin I metabolism in aorta of apoE-knockout mice

The detrimental role of over activation of renin-angiotensin system (RAS) in atherogenesis is widely recognized. Recently, we have demonstrated that Ang-(1-7) peptidomimetic - AVE0991, as well as known beta-adrenolytic agent nebivolol, exert anti-atherogenic actions in mouse model of atherosclerosis - apoE-knockout mice. Here, using LC-ESI-MS ex vivo system, we tested whether prolonged treatment of apoE-knockout mice by these drugs can influence RAS in aorta of apoE-knockout mice in regard to generation of most active metabolites of Ang I-Ang II and Ang-(1-7). As compared to wild type animals there was increased generation of Ang II in aorta of apoE-knockout mice, while the formation of Ang-(1-7) did not differ between both groups. Either treatment with AVE0991 or nebivolol resulted in significant attenuation of Ang II production in aorta of apoE-knockout mice. In conclusion, for the first time we directly demonstrated that there is increase in ability of aortic tissue to generate Ang II in mouse model of atherosclerosis of apoE knockout mice, and that such effect could be efficiently attenuated either by treatment of nebivolol or Ang-(1-7) peptidomimetic - AVE0991. The exact mechanism(s) responsible for interference of both drugs with RAS require further investigation.

Influence of atorvastatin on angiotensin I metabolism in resting and TNF-α -activated rat vascular smooth muscle cells

INTRODUCTION

Vascular smooth muscle cells (VSMCs) are essential for maintaining vasculature homeostasis and function. By influence on its growth and activation both proinflammatory cytokines and peptides of the renin-angiotensin system (RAS) are potent regulators of VSMCs. Interestingly, angiotensin (Ang) II and Ang-(1-7) elicit opposite effects on VSMC activation, differentiation and proliferation. It has been suggested that statins, besides anti-inflammatory effects, may also modulate VSMC activation by their influence on the RAS.

METHODS

The effect of atorvastatin on Ang I metabolism in a culture of explanted rat VSMCs was examined by liquid chromatography-mass spectrometry (LC-MS); expression of mRNA of the main RAS enzymes in VSMC was assessed by real-time polymerase chain reaction (PCR).

RESULTS

In VSMC culture Ang-(1-7) was identified as a major product of Ang I metabolism. In this setting, TNF-α (1 ng/ml) caused a decrease in the conversion of Ang I to Ang-(1-7). This effect was accompanied by a decrease of mRNA expression of neutral endopeptidase (NEP) and angiotensin converting enzyme 2 (ACE2) and increase of mRNA of ACE. Interestingly, atorvastatin (3 μM) attenuated the effects of TNF-α on Ang-(1-7) production as well as reversed the influence of TNF-α on ACE and ACE2 expression.

CONCLUSIONS

Enhancement by atorvastatin of the ACE2/Ang-(1-7) axis in VSMCs could represent a new and beneficial mechanism on cardiovascular action of this widely used drug.

Elevated interleukin-1β serum level after chronic peripheral salsolinol administration

The catechol isoquinoline derivatives are endogenous compounds present in the mammalian brain and the representative one is referred to as salsolinol. It may be formed from aromatic amines leading to neurotoxic N-methyltetrahydroquinolinium ions that may play a role in the etiology of Parkinson's disease (PD). Neuroinflammation and apoptosis is thought to be a major contributor to the neuronal degeneration in PD. The alteration of inflammatory cytokines in the brain, cerebral spinal fluid and plasma of PD patients supports the existence of functional interconnections between the immune and nervous systems. In animal studies, chronic administration of salsolinol induced parkinsonian-like symptoms, both peripherally and centrally. However, still little has been known about the effects of salsolinol on the pro-inflammatory cytokine production or mast cells activation in the gastrointestinal tract. Male Wistar rats were subjected to continuous intraperitoneal dosing of salsolinol (200 mg/kg in total) with osmotic mini-pumps for two or four weeks and fed with either standard or high fat diet. An equivalent group of rats served as the appropriate controls. At the end of the experiment animals were decapitated and blood samples as well as tissue fragments were collected. Serum samples were assayed immunoenzymatically for IL-11β and by liquid chromatography-mass spectrometry for histamine. Tissue fragments from gastric antrum, duodenum and proximal colon were formalin fixed, paraffin-embedded and stained with either hematoxylin and eosin or toluidine blue. Once activated, mast cells might secrete a range of neurosensitizing and pro-inflammatory molecules, increasing gut-blood and blood-brain barrier permeability. Cytokines mediate the activity of immune cells and may affect brain neurochemistry. The results of the present work serve as an additional support for the existence of an interrelationship between the nervous and immune system.

The influence of salsolinol on basic rat metabolism

Parkinson's disease (PD) is associated with a broad spectrum of non-motor symptoms, which are poorly understood and foremost, may precede motor impairment. These symptoms include weight changes and gastrointestinal dysregulation. In our experiment, we applied salsolinol given peripherally and continuously in rats to induce changes in the enteric nervous system, which might be similar to those observed in PD patients. Surprisingly, we noted decrease in body weight and alteration in body fat contents of the animals during salsolinol exposure. The blood glucose levels, lipid profile and hepatic enzymes levels were assessed as well. While lipid profile, postprandial blood glucose and hepatic enzymes levels remained indifferent, postprandial triglyceridemia was significantly lower in all salsolinol-treated rats in comparison with the control, which might be related to disturbed absorption. We also suggest that diminished body weight gain and lower adipose tissue accumulation in salsolinol-treated animals were due to delayed gastric emptying together with disturbed gut function resulting in absorptive dysfunction.

Co-administration of dextromethorphan and morphine: reduction of post-operative pain and lack of influence on morphine metabolism

We investigated co-analgesic effect of dextromethorphan in adolescent post-operative patients with idiopathic scoliosis. In a double-blind study, 60 patients with ASA physical status I-II were randomised into two groups. Group dextromethorphan (n = 30; age: 15.9 +/- 2.4 years) was given oral dextromethorphan 30 or 45 mg 1 hr before surgery and 8, 20 and 32 hr after operation. Group placebo (n = 30; age: 16.5 +/- 2.7 years) received placebo at identical times. Post-operative analgesic requirements were assessed using nurse-controlled analgesia system. Pain was assessed using numeric rating scale before first administration of morphine and at 2, 3, 4, 6, 24 and 48 hr after operation. Blood samples were taken 20 min. after the first use of morphine (within 1 hr after operation). The total use of analgesics during surgery was lower in the dextromethorphan group. The dose of morphine providing relief immediately after surgery, as well as total analgesic requirements in the first and second day after surgery did not differ between groups. Subjectively evaluated pain intensity score (numeric rating scale) was lower for the dextromethorphan patients in the first 4 hr, but not later after surgery. Plasma levels of morphine, morphine-6-glucuronide and morphine-3-glucuronide did not differ between groups. Dextromethorphan did not influence morphine glucuronidation, in terms of promotion of formation of any morphine glucuronides. In conclusion, in young patients subjected to spine surgery, addition of dextromethorphan to morphine reduced pain only in early post-operative period. In such patients, co-analgesic action of dextromethorphan was not associated with significant changes in plasma levels of morphine metabolites.

Angiotensin metabolism in rat stomach wall: prevalence of angiotensin-(1-7) formation

Our view of renin-angiotensin system (RAS) has changed over the past two decades: new metabolites and pathways have been described; also the importance of local renin-angiotensin systems became more clearly understood. However, there is relatively scarce information about formation and action of angiotensin peptides in gastrointestinal tract, especially in the stomach. Here, using LC-ESI-MS method we assessed the metabolism of Ang I in organ bath of rat stomach wall. Additionally we compared the expression of mRNA of angiotensin converting enzymes (ACE, ACE2) and neprilysin (NEP) in the stomach, aorta and renal artery in rats. Despite, similar levels of expression of ACE and ACE2 mRNA in stomach wall, aorta and renal artery, the absolute amounts of main Ang I metabolites produced by stomach wall (in ng/mg of dry tissue) were much lower than that produced by aorta and renal artery. Also, the pattern of angiotensin I metabolites was different: opposite to aorta and renal artery, incubation of Ang I with stomach wall fragments resulted in predominant formation of Ang-(1-7) and relatively lower production of Ang II. In stomach wall both, perindoprilat and tiorphan decreased production of Ang II, but did not influence generation of Ang-(1-7). In conclusion, we identified Ang-(1-7) as the main product of Ang I conversion in rat stomach wall. The biological role of prevalence of Ang-(1-7) formation in stomach require further investigation.

Tumor-associated Carbohydrate Antigens: Sialyl Lea and T/Tn Antigens in Canine Mammary Tumors

Twenty-eight canine mammary tubulopapillary carcinomas and 14 simple adenomas were studied by immunohistochemistry for the expressions of the tumor-associated carbohydrate antigens. Sialyl Lea was detected in 71.42% of the malignant and 92.84% of the benign tumors. Staining with anti-T and anti-Tn monoclonal antibodies revealed that 85.70% of the tubulopapillary carcinomas expressed T and Tn antigens. In contrast, 50% of the adenomas did not express T antigen, and 42.85% of them were only weakly stained for this carbohydrate structure. In the case of Tn antigen, the majority (57.14%) of samples was weakly stained, and no binding was observed in 35.71% of the analyzed specimens. Comparison of average values of reaction intensity (IRS) scale for malignant versus benign tumors by the Mann-Whitney U-test revealed a significant relationship between T and Tn antigens expression and type (malignant vs. benign) mammary tumors. Based on the results obtained, it is suggested that each of the studied antigens can be treated as a tumor-associated antigen of canine mammary tumors. However, only the T and Tn antigens seem to be associated with malignant transformation of mammary gland cells and to be of potential value as diagnostic markers.

Kaempferol, but not resveratrol inhibits angiotensin converting enzyme

Inhibition of angiotensin converting enzyme (ACE) has proved to be beneficial in the treatment of various cardiovascular disorders. The aim of this study was to evaluate ACE inhibitory potential of two polyphenolic compounds with different structures: resveratrol (present in high quantities in French wine) and kaempferol (abundant in greens), using method of liquid chromatography coupled with electrospray ionization mass spectrometry (LC-ESI-MS) for ex vivo measurement of angiotensin I to angiotensin II conversion by ACE in aortic tissue of Wistar-Kyoto rats. In this setting, kaempferol (10-30-100 microM), but not resveratrol (10-30-100 microM) appeared to inhibit dose-dependently conversion of Ang I to Ang II. Although the mechanism of ACE inhibition by kaempferol remains to be elucidated, this observation may help in search or designing of new classes of ACE inhibitors.

Measurement of angiotensin metabolites in organ bath and cell culture experiments by liquid chromatography - electrospray ionization - mass spectrometry (LC-ESI-MS)

The metabolism of renin-angiotensin system (RAS) is more complicated than previously expected and understanding the biological phenomena regulated by variety of angiotensin metabolites requires their precise and possibly comprehensive quantitation. Physiological concentrations of angiotensins (Ang) in biological fluids are low, therefore their accurate measurements require very sensitive and specific analytical methods. In this study we developed an accurate and reproducible method of quantitation of angiotensin metabolites through coupling of liquid chromatography and electrospray ionization - mass spectrometry (LC-ESI-MS). With this method main angiotensin metabolites (Ang I, II, III, IV, 1-9, 1-7, 1-5) can be reliably measured in organ bath of rat tissues (aorta, renal artery, periaortal adipose tissue) and in medium of cultured endothelial cells (EA.hy926), exposed to Ang I for 15 minutes, in the absence or in the presence of angiotensin converting enzyme inhibitor, perindoprilat. Presented LC-ESI-MS method proved to be a quick and reliable solution to comprehensive analysis of angiotensin metabolism in biological samples.

Changes in gene expression in the lungs of Mg-deficient mice are related to an inflammatory process

It has been well documented that experimental hypomagnesemia in rodents evokes, as an early consequence, an inflammatory response. This also leads to the activation of cells producing reactive species of oxygen and, as a result, to the oxidative damage of tissues. Several studies have shown that lungs might be a specific target of Mg deficiency. Here, we report that 3 weeks of Mg deficiency in mice resulted in inflammatory processes in the lungs, including interstitial and perivascular pneumonia, manifested by the infiltration of leukocytes, plasmocytes and histiocytes, as well as the phenomenon of disseminated intravascular coagulation (DIC). These phenomena were accompanied by changes in gene expression assessed by cDNA array. In this study we identified 26 genes significantly changed by Mg deficiency, mostly involved in the anti-oxidative response, regulation of cell cycle and growth, apoptosis as well as cell-cell and cell-matrix interactions. We conclude that these changes are related to the phenomena of inflammatory and oxidative processes and consecutive remodeling occurring in the tissues as a result of Mg deficiency. This may have implications for at least several lung pathologies, including allergies, asthma, SIDS (Sudden Infant Death Syndrome) or facilitate formation of lung metastases.

Secretory dysfunction of vascular endothelium limits the effect of angiotensin converting enzyme inhibitor quinapril on aggregation of erythrocytes in experimental hypertension

Using automatic erythrocyte aggregometer type MA-1 (Myrenne gmbh, Germany), we investigated the hypothesis that therapeutic effectiveness of quinapril--angiotensin converting enzyme inhibitor (ACEI)--in the treatment of hypertension would correlate with improvement of red blood cell (RBC) aggregability. Experiments were performed on commercially available inbred strain of spontaneously hypertensive male rats (SHR) aged 19-21 weeks. Age-matched normotensive Wistar-Kyoto (WKY) rats genetically related to SHR were used as a control. Aggregability of RBC in hypertensive rats was significantly higher than in control WKY animals. Quinapril (100 microg/kg) administered i.p. for 8 days improved RBC aggregability in normotensive rats but surprisingly not in SHR animals. Beneficial effect of quinapril on RBC aggregation observed in normotensive animals did not occur when this drug was injected in combination with aspirin (1 or 50 mg/kg) or with indomethacin (20 mg/kg) or with L-NAME (10 mg/kg). However, much the same damaging effects on RBC aggregability were observed when aspirin, indomethacin or L-NAME were each administered into normotensive animals without quinapril. In contrast with normotensive rats, aggregability of RBC in SHR was not affected either by quinapril or by indomethacin and by L-NAME, given separately or in combination. The only compound significantly worsening RBC aggregability in SHR was aspirin but this effect was not dose-dependent. Quinapril-induced improvement of RBC aggregability in normotensive rats (but not in SHR) was completely abolished by simultaneous administration of B2 receptor antagonist icatibant and successfully mimicked by 8 days of treatment with bradykinin. In vitro aggregability of RBC isolated from WKY was not affected by previous incubation (30 min at 37 degrees C) with quinapril, indomethacin or L-NAME. Only aspirin (3 mM) significantly increased RBC aggregability as compared to placebo. It is concluded that under physiological conditions quinapril efficiently inhibits RBC aggregability and this effect is modulated by secretion of endothelial mediators, mainly prostacyclin and nitric oxide. In hypertension quinapril, in spite of lowering of arterial blood pressure, is unable to display its beneficial effects on RBC aggregability possibly due to the hypertension-induced/accompanied dysfunction of vascular endothelium. Aspirin revealed unique erythrocyte damaging properties, presumably independent of inhibition of cyclooxygenase but related to a direct membrane protein acetylation.

Ultrastructural studies on malignant lymphoma in dogs, with the use of computer imaging

Malignant lymphoma is one among the most often diagnosed malignant tumors in dogs. In the course of the disease lymphatic glands become enlarged and infiltrations form in internal organs or skin. Studies on the ultrastructure of neoplastic lymphocytes were carried out on a formalin-fixed and parafin-embedded material with a Hulquist and Karlsson's method. Numerous aplastic cells with large nuclei, abundan eu- or heterochromatin and unstabilised nucleolus were observed on TEM slides. The cells differed clearly from normal lymphocytes with highly condesed heterochromatin and stabilised nucleoli.

Endothelial secretogogues and deformability of erythrocytes

Many diseases of the heart and circulatory system have been linked with both dysfunction of vascular endothelium and insufficient deformability of erythrocytes. Using shear stress laser diffractometry we investigated whether deformability of erythrocytes would be regulated endogenously by generation of two endothelial secretogogues: prostacyclin and nitric oxide. Experiments were performed in rats ex vivo and with whole blood or isolated erythrocytes in vitro. Iloprost--a stable analogue of prostacyclin (10 microg/kg i.v.) and SIN-1 (NO-donor) at a dose of 2 mg/kg/min i.v induced a significant improvement of deformability of erythrocytes ex vivo. Improvements of deformability by these two compounds were also evident in vitro when they were applied at a range of concentrations of 1 microM and 3 microM, respectively. Cyclooxygenase (indomethacin 20 mg.kg i.v.) and nitric oxide synthase (L-NAME 10 mg/kg i.v.) inhibitors while worsening deformability ex vivo, they did not affect (3 mM and 10 microM, respectively) rheological functions of erythrocytes in vitro. Aggravating effects of these inhibitors on erythrocyte deformability ex vivo were reversed by prostacyclin and nitric oxide supplemented exogenously. Aspirin at a low (1 mg/kg i.v.) and high dose (50 mg/kg i.v.), contrary to indomethacin and L-NAME, aggravated erythrocyte deformability either ex vivo or in vitro. It is concluded that autocrine function of vascular endothelium plays an important role in regulation of rheology of red blood cells in flowing blood. The mechanism of this phenomenon is unclear but some possible explanations are discussed. In addition, in our experiments aspirin revealed unique erythrocyte damaging properties, possibly independent of inhibition of cyclooxygenase, but related to a direct protein acetylation.

Activity of glycogen depolymerizing enzymes in extracts from brain tumor tissue (anaplastic astrocytoma and glioblastoma multiforme)

An approximately threefold increase in glycogenolytic activity of the neutral alpha-1,4-glucosidase and a twofold increase in the same activity of the acid isoform have been found in extracts of anaplastic astrocytoma and glioblastoma multiforme tumors of brain tissue. "Maltase activity" of the respective enzymes increased by 60-80% in both kinds of tumor extracts. However a significant decrease in a-amylase and almost complete disappearance of phosphorylase activities have also been found in both kinds of tumors.

Mesoionic oxatriazoles (MOTA): NO-donating characteristics and pharmacology

Biological role of nitric oxide (NO), functioning of isoforms of NO synthetases (NOS) and pharmacology of principle NO-donors were reviewed. NO donating characteristics and pharmacology of 23 mesoionic oxatriazoles (MOTA) were compared with those of 5-morpholinosydnonimine (SIN-1), S-nitroso-N-acetylpenicillamine (SNAP), sodium nitroprusside (NaNP) and glyceryl trinitrate (GTN). It is concluded that in vitro NO donating profile of MOTA hardly can be used as a predicting measure for their pharmacological activities either in vitro or in vivo. If anything, fast NO releasers seem to be stronger vasorelaxants than MOTA with slow NO releasing properties. Still, among representatives of this last category of MOTA one may find efficient antithrombotic and thrombolytic agents. For instance, MOTA 5-oxides were more potent thrombolytics than SIN-1, SNAP or NaNP. Also MOTA with potent anti-platelet action in vitro seem to be potent relaxants of tracheal strips. In summary, by manipulating the chemical structures of MOTA one may obtain relative selectivity towards vasorelaxant, anti-platelet, thrombolytic or tracheorelaxant properties. Thus different categories of MOTA might be designed with a hope of achieving hypotensive, antithrombotic, thrombolytic or anti-asthmatic drugs.

Activity of glycogen depolymerizing enzymes in extracts from brain tumor tissue (anaplastic astrocytoma and glioblastoma multiforme)

An approximately threefold increase in glycogenolytic activity of the neutral alpha-1,4-glucosidase and a twofold increase in the same activity of the acid isoform have been found in extracts of anaplastic astrocytoma and glioblastoma multiforme tumors of brain tissue. "Maltase activity" of the respective enzymes increased by 60-80% in both kinds of tumor extracts. However a significant decrease in a-amylase and almost complete disappearance of phosphorylase activities have also been found in both kinds of tumors.

Comparison of endothelial pleiotropic actions of angiotensin converting enzyme inhibitors and statins

Two in vitro and one in vivo assay were performed to study the endothelial pleiotropic actions of "tissue type" angiotensin converting enzyme inhibitors (ACE-Is) such as perindopril and quinapril, their active forms, that is, quinaprilat and peridoprilat, or of statins belonging to natural (lovastatin), semisynthetic (simvastatin), and synthetic enantiomeric (atorvastatin, cerivastatin) classes. Cytoplasmic [Ca2+]i levels in cultured bovine aortic endothelial cells and endothelium-dependent nitric oxide-mediated coronary vasodilatation in the Langendorff preparation of guinea pig heart constituted our in vitro assays. The in vivo assay consisted of study of PGI2-mediated thrombolytic response in arterial blood of rats after intravenous administration of drugs. In this last assay, perindopril and quinapril proved to be, by two orders of magnitude, more potent PGI2-dependent thrombolytics than the most potent statin (atorvastatin). However, in both in vitro assays we found a higher endothelial efficacy of statins as compared to ACE-Is. In particular, those statins that contain the lactone ring in their molecules (lovastatin, simvastatin) were the most potent coronary vasodilators. In summary, the in vivo profile of action of ACE-Is and statins contrasted with their reversed order of potency in vitro. We hypothesize that the endocrine-like function of the pulmonary circulation [28-31] may be responsible for the in vivo bradykinin-triggered, PGI2-mediated thrombolysis by ACE-Is, whereas the pleiotropic action of statins, possibly involving inhibition of prenylation [14-19], is diffused throughout many vascular beds.

Bioastrophysical aspects of low energy ion irradiation of frozen anthracene containing water

The origin of life on Earth remains a fascinating mystery in spite of many theories existing on this subject. However, it seems that simple prebiotic molecules could play an essential role in the formation of more complex organisms. In our experiment, we synthesized a class of these molecules (quinones) bombarding frozen anthracene containing water with low energy hydrogen ions. This experiment roughly simulated the astrophysical conditions which one can find in the solar system. Thus, we can hypothesize that prebiotic molecules could be created by interaction of the solar wind with interplanetary dust grains. The delivery of these molecules to early Earth may have contributed to the generation of life on our planet.

[Postero-medial release in surgical treatment of congenital clubfeet: a comment to Turco's method based on personal experience]

Complete correction of congenital clubfeet by conservative treatment is often impossible. Surgical treatment plays a major role in treatment of this deformity. At the Department of Pediatric Orthopedics in Lublin between 1970 and 1999 1041 children (1253 feet) were treated surgically with Turco's method, in the authors' own modification. The paper presents the technically optimal procedure, the range of tendon elongation. The way the wound is closed is particularly stressed, as well as the need to achieve muscle balance, along with a description of proper post-op care. The material was analysed as a whole, although particular attention was given to three periods: 1970-1975, 1980-1985, 1990-1995. The results were assessed according to the Turco classification, the Magone classification in accordance with the injunctions of the Scientific Committee Meeting of the Pediatric Section of the Polish Orthopedic Society held in Poznan. Good and very good results were achieved in 65-67% of the cases, while satisfactory and bad results were found in 23-30% of the cases.

Thrombolysis by thienopyridines and their congeners

We propose that anti-platelet thienopyridines, such as ticlopidine or clopidogrel, are thrombolytic owing to endothelial release of prostacyclin (PGI2) and tissue plasminogen activator (t-PA). In this study we used anaesthetised Wistar rats with extracorporal circulation in which arterial blood superfused thrombi which adhered to a strip of collagen. Weight of thrombi was continuously monitored. When administered intravenously, clopidogrel or its R enantiomer deprived of anti-platelet action, both at doses of 3 mg x kg(-1), produced lost in weight of thrombi by 14.1 +/- 1.3% or 16.0 +/- 1.4% (n = 9), and at doses 10 mg x kg(-1) by 28.3 +/- 2.3% or 30.4 +/- 1.9% (n = 8), respectively. Maximum of thrombolysis occurred 30-45 min following the drug administration. Ticlopidine at a dose of 30 mg x kg(-1) reduced weight of thrombi by 33.7 +/- 1.7% (n = 32). Thrombolytic action of ticlopidine was accompanied by a rise in 6!keto-PGF1alpha blood levels from 0.42 +/- 0.10 to 1.58 +/- 0.29 ng x ml(-1) and t-PA antigen plasma levels from 4.70 +/- 1.00 to 12.90 +/- 1.15 ng x ml(-1) (n = 7). Five out of eleven tested thienopyridine congeners with pyrimidine or pyrimidinone instead of pyridine rings had thrombolytic potencies similar to that of clopidogrel (ED30s at a range of 6.2-11.4 mg x kg(-1)). A substantial increase in thrombolytic potency (ED30s at a range of 0.3-2.1 mg x kg(-1)) was observed for congeners in which thienyl ring was condensed with an additional cyclopentyl, cyclohexyl or cycloheptyl structures or in which thienopyridine complex was replaced for a pyridopyrimidine one. We claim that thienopyridines, independently of their delayed anti-platelet action, do produce immediate thrombolysis in vivo. This new activity emulates capacity of their native, non-metabolised molecules to release prostacyclin and tissue plasminogen activator. We have also shown that structural changes in molecules of thienopyridines may intensify their thrombolytic potency.

The antitumor effect of postoperative treatment with genistein alone or combined with cyclophosphamide in mice bearing transplantable tumors

Genistein has been shown to be an inhibitor of tumor growth as well in vitro as in vivo. In addition to its antitumor effect, genistein reveals the antimetastatic and antiangiogenic properties. In this paper we described the results of our studies on the antimetastatic activity of genistein alone or combined with cyclophosphamide (CY) in mice which before this treatment were exposed to surgical excision of the primary tumor. Three transplantable subcutaneously growing mouse tumors were applied: Lewis lung cancer (LL2), B16F-10 melanoma and 16/C mammary cancer. The antitumor and antimetastatic effect was evaluated by the estimation of a number of lung colonies and a number of primary tumor recurrence as compared to the control mice exposed to the s.c. tumor extirpation only. Twenty days after the surgery, an average of 52 lung tumor colonies per mouse were detected in control mice bearing LL2 cancer. The treatment with genistein resulted in the reduction of the lung colonies to 24 per mouse. The treatment with CY reduced the number of lung colonies to 12 (p < 0.05) and combined treatment with both agents to 4 (p < 0.05). The percentage of primary tumor recurrence was 25, 86, 67 and 80% in the control, genistein treated, CY treated, and genistein + CY treated mice, respectively. Twenty days after the surgery, no lung metastases in the control mice bearing B16F-10 melanoma were observed. The percentage of primary tumor recurrence in the control, genistein treated, CY treated and genistein + CY treated mice was: 86, 29, 57 and 67% respectively. Two different protocols of the treatment with genistein were applied in 16/C mammary cancer model. In the first one genistein was injected before and in the other after surgical excision of tumor. The histological examination revealed the presence of lung metastases in all, untreated and treated, according to both protocols groups of mice. The percentage of primary tumor recurrence in the control mice, genistein treated according to the protocol I, and II was: 100, 40, and 40%, respectively.

Antitumour and antimetastatic effect of genistein alone or combined with cyclophosphamide in mice transplanted with various tumours depends on the route of tumour transplantation

In the present study we evaluated the antitumour effect of genistein alone, cyclophosphamide alone and as a combined therapy with both agents in mice transplanted with B16F-10 melanoma and Lewis lung cancer cells. The influence of the route of inoculation of the tumour cells on the antitumour and antimetastatic effects of these therapeutics was evaluated. The antitumour effect of genistein in mice with B16F-10 intradermically (i.d.) growing tumours and in mice with LL2 subcutaneous (s.c.) tumours was observed. In addition, its antimetastatic effect (reduction of lung colonies) in mice inoculated intravenously (i.v.) with B16F-10 and in mice with LL2 cells injected either intravenously or subcutaneously was observed. No life span prolongation of mice injected intraperitoneally (i.p.) with B16F-10 cells was observed, either after treatment with genistein alone or with cyclophosphamide alone. The synergistic effect of both agents in combined treatment, when the cells of B16F-10 melanoma were injected i.p., i.v. or i.d. and in a weaker manner when the cells of LL2 cancer were injected s.c., was observed. When LL2 cells were injected intravenously, no additive effect of genistein and CY could be detected. In conclusion, we have described the experimental mouse tumour models in which both the antitumour and antimetastatic effects of genistein alone, CY alone and those of combined therapy with genistein and cyclophosphamide were dependent on the implantation route of the tumour cells.

Metastatic potential of human uroepithelial cancer cells is not dependent on their adhesion to E-selectin

In our previous studies we have found that human uroepithelial cell lines differ in their expression of sialosyl LewisA antigen. We have also shown that among the studied cell lines, only Hu 1703He cells with the highest expression of this tetrasaccharide bind to E-selectin-expressing cells. In the present study we put forward the question, of whether sialosyl LewisA-mediated adhesion of uroepithelial cells to E-selectin is important in the formation of metastases. The HCV 29T and Hu 1703He cells, representing two uroepithelial cell lines, were transplanted into NCr nu/nu mice. Hu 1703He cells express on their surface a high level of sialosyl LeA antigen, while HCV 29T cells are sialosyl LewisA-negative. We have shown that human uroepithelial cancer cells, in addition to their tumorigenic and invasive properties, are highly metastatic when inoculated into athymic nu/nu mice. The ability to form secondary tumour foci in lung and liver seems to be independent of the expression of sialosyl LewisA antigen.

[Contemporary model for treatment of erythroplakia]

In literature worldwide is still commonly used the term erosion to describe red areas within cervix around the external orifice. In such cases with negative cytology result, for cervical cancer prevention, the electrocoagulation or electro-conisation or other destructive operations are routinely used. Without colposcopy verification such management is inappropriate. The physician treats but does not know what he treats. It may be both common ectopy or regeneration zone so physiologic cervical states but it may be also CIN or even early cervical cancer, however cytologically negative. The first group of lesions is effectively diagnosed with colposcopy without additional diagnostic procedures and the CIN lesions are diagnosed in high percentage of accuracy. Not all of these lesions should be treated. In the group of colposcopically and cytologically unsuspected lesions just very extensive lesions with active mucous glands should be treated. Such lesions cause recurrent cervical inflammation. All other erythroplakia type lesions demand no treatment. The presence of ectopy around the external cervical orifice is just profitable for diagnosis of epithelial changes and cervical physiologic processes observation. All cases of abnormal colposcopy or cytology results, suspected of CIN should be treated as prevention of cervical cancer. In lower CIN grades electroresection (LEEP) is recommended, while in higher grades the cervical conisation is the appropriate mode of treatment.

Metastatic potential of human CX-1 colon adenocarcinoma cells is dependent on the expression of sialosyl Le(a) antigen

Several lines of evidence indicate that sialosyl Le(a), tumor-associated carbohydrate antigen present on human colon carcinoma cells, is involved in formation of metastases. To study the role of this carbohydrate structure in development of metastases, we have used the clone of human colon carcinoma CX-1 cells transfected with antisense expression vector containing fragment of cDNA for alpha1,3/4-fucosyltransferase (FT III), which is involved in synthesis of sialosyl Le(a) tetrasaccharide. It has been reported previously that, in contrast to the parental cells, the antisense-transfected CX-1.1AS5 cells do not express sialosyl Le(a) and do not adhere to E-selectin-expressing CHO cells. In the present work we have studied the formation of liver metastases by CX-1.1AS5 cells after their orthotopic or intrasplenic implantation into athymic nu/nu mice. After orthotopic implantation of sialosyl Le(a)-negative colon carcinoma CX-1.1AS5 cells, the number of mice with liver metastases was markedly lower (21% of mice) in comparison with their number after implantation of the parental CX-1.1 cells (86% of mice). However, no differences in ability to form colonies in liver were observed between parental CX-1.1 cells and antisense-transfected CX-1.1AS5 cells after intrasplenic inoculation. The liver metastases were formed in 89% and 84% of mice, respectively. Our data support the thesis on the importance of sialosyl Le(a) antigen expression in the development of liver metastases by colon cancer cells, and indicate the role of transplantation route and primary tumor localization in formation of metastases.

Decidual ectopy on the uterine cervix. The diagnostic and clinical considerations

On the basis of our clinical experience and literary data there were presented views on etiopathogeny of decidual transformations of the uterine cervix. Localization and colposcopic pictures of these lesions were discussed, and according to our clinical data discrimination between four forms of decidual ectopy was carried out. The vessel pattern of these changes, visible in colposcopic picture was characterized as well as its differentiation from vascular picture of malignant lesions. Possibility of cytological diagnosis in cases of decidual ectopy was also noted. On the basis of many years clinical experience there was showed the importance of colposcopic diagnosis of decidual ectopy in evaluation of early pregnancy and its complications.

[Significance of vascular changes in the colposcopic diagnosis of precancerous and early stages of cervical cancer]

Blood vessels are visible in an average of 80% of patients on whom colposcopy is performed. This percentage share increases if there are pathological changes. The following vascular types occur as characteristic criteria in cervical intraepithelial neoplasia (CIN) and in carcinoma, their classification being based on structural properties such as calibre, long and intercapillary spaces, shape and arrangement of the vessels, as well as their functional state: Abnormal vessels; pathological vessels of the 1st and 2nd degree; uncharacteristic vessels (also known as "troubled vessels"). The author discusses the architecture, adaptive vasodilation and formation of new vessels in connection with morphological changes in the epithelium. Their occurrence is evaluated statistically, and an inference is drawn from these studies on the efficiency of vascular diagnosis. The following conclusions are arrived at on the basis of the examined material: The abnormal vessel result from a proliferation of the abnormal or dysplastic epithelium. The pathological vessels of the 1st degree occur as maximum type of adaptive vascular change resulting in the course of carcinomatous proliferation. The pathological changes of the 2nd degree, on the other hand, become visible as new formations in invasively growing carcinomas only. There is a connection between the presence of pathological types of vessels and the carcinomatous degeneration of the epithelium and the invasive growth. Assessment of the vessels must be performed parallel to the assessment of the epithelium via acetic acid or lactic acid test. This facilitates colposcopic diagnosis of precarcinomic and early stages of cervical carcinoma and enables conclusions to be drawn on an invasive growth of the carcinoma.

Serum lipoproteins, lipid peroxides and prostacyclin biosynthesis in patients with coronary heart disease

Serum low-density lipoproteins (LDL) and high-density lipoproteins (HDL) were prepared by gradient ultracentrifugation and dialysis from 12 healthy subjects and 15 patients with coronary heart disease and hyperlipoproteinemia. In both lipoprotein fractions cholesterol and lipid peroxides were determined. The effect of these lipoproteins on spontaneous prostacyclin biosynthesis in rat aortic slices was studied. Serum lipoproteins were susceptible to peroxidation during the preparation procedure. LDL were more prone to peroxidation than HDL. Little lipid peroxides were formed in lipoproteins when calcium ions had been removed by EDTA, and when butylated hydroxytoluene (BHT) was present at all stages of their preparation. LDL when prepared without these precautions either from healthy subjects or from patients with coronary heart disease markedly suppressed prostacyclin generation by rat aortic slices. This inhibition was unrelated to LDL-cholesterol, but was due to LDL-lipid peroxides. Peroxide-low LDL prepared from most of the healthy subjects and patients with coronary heart disease and concomitant hyperlipoproteinemia, did not inhibit prostacyclin biosynthesis. However, in one quarter of the patients, LDL was inhibitory. Consequently, in some patients with coronary heart disease, there operate unknown mechanisms which are responsible for the inhibitory activity of LDL on prostacyclin generation.