The effect of ethion on erythrocyte deformability.

Organophosphates cause increased oxidative susceptibility of erythrocytes and changes in erythrocyte deformability ability. We aim is to investigate the role of ethion (ETH) on erythrocyte deformability and to show whether vinpocetine (VIN) and carnosine (CAR) are protective against these changes. The study was performed on Sprague Dawley rats with an average weight of 220 ±â€¯40 g and 4-5 months old. Six experimental groups were composed of 10 rats per group. Hematological parameters, erythrocyte deformability, % hemolysis, 2.3bisphosphoglycerate, and methemoglobin values were measured in blood samples taken after 10 days of drug application. Erythrocyte count, hemoglobin amount, hematocrit value, serum potassium level, and erythrocyte deformability decreased in the ETH group. Leukocyte, platelet count, methemoglobin amount, and % hemolysis rates increased in the ETH group. The values of the ETH + CAR and ETH + VIN groups were found to be closer to the control group. In organophosphate poisoning such as ETH, the deformability ability of erythrocytes exposed to constant oxidative stress is changing, and therefore their ability to deliver oxygen to tissues is negatively affected. VIN and CAR may have improve on erythrocyte deformability in this type of intoxication.

Seasonal variations in body composition, maximal oxygen uptake, and gas exchange threshold in cross-country skiers.

INTRODUCTION: In order to ensure that athletes achieve their highest performance levels during competitive seasons, monitoring their long-term performance data is crucial for understanding the impact of ongoing training programs and evaluating training strategies. The present study was thus designed to investigate the variations in body composition, maximal oxygen uptake (VO2max), and gas exchange threshold values of cross-country skiers across training phases throughout a season. MATERIALS AND METHODS: In total, 15 athletes who participate in international cross-country ski competitions voluntarily took part in this study. The athletes underwent incremental treadmill running tests at 3 different time points over a period of 1 year. The first measurements were obtained in July, during the first preparation period; the second measurements were obtained in October, during the second preparation period; and the third measurements were obtained in February, during the competition period. Body weight, body mass index (BMI), body fat (%), as well as VO2max values and gas exchange threshold, measured using V-slope method during the incremental running tests, were assessed at all 3 time points. The collected data were analyzed using SPSS 20 package software. Significant differences between the measurements were assessed using Friedman's twoway variance analysis with a post hoc option. RESULTS: The athletes' body weights and BMI measurements at the third point were significantly lower compared with the results of the second measurement (p<0.001). Moreover, the incremental running test time was significantly higher at the third measurement, compared with both the first (p<0.05) and the second (p<0.01) measurements. Similarly, the running speed during the test was significantly higher at the third measurement time point compared with the first measurement time point (p<0.05). Body fat (%), time to reach the gas exchange threshold, running speed at the gas exchange threshold, VO2max, amount of oxygen consumed at gas exchange threshold level (VO2GET), maximal heart rate (HRmax), and heart rate at gas exchange threshold level (HRGET) values did not significantly differ between the measurement time points (p>0.05). CONCLUSION: VO2max and gas exchange threshold values recorded during the third measurements, the timing of which coincided with the competitive season of the cross-country skiers, did not significantly change, but their incremental running test time and running speed significantly increased while their body weight and BMI significantly decreased. These results indicate that the cross-country skiers developed a tolerance for high-intensity exercise and reached their highest level of athletic performance during the competitive season.

Changes of red blood cell rheology in newborns with congenital hypothyroidism during treatment.

AIM: We aimed to evaluate the deformability characteristics of RBC and the affecting factors in newborns diagnosed with congenital hypothyroidism (CH) and to compare the outcomes after the L-thyroxin treatment. PATIENTS AND METHODS: Enrolled subjects were divided into two subgroups as "patients" and age-matched healthy "controls". First blood samples were taken from all subjects for measuring elongation index (rEI) and osmotic fragility of RBC (OF), hematic and biochemical analytes affecting the RBC deformability in the neonatal age. All parameters were repeated a month after provided euthyroid state following the treatment in patients and age-matched healthy controls. RESULTS: There was no difference between both groups in terms of complete blood count parameters and serum analytes (albumin, bilirubin and fibrinogen) except expected age-related changes in the first and second readings. Serum lipid/lipoprotein levels of both groups remained unchanged except triglyceride levels during the study period. The rEI of the patients were lower than that of controls in the first and second readings. The rEIs of the patients became increased, reaching (not equal) the levels of their controls during L-thyroxin treatment. Osmotic fragility of the patients was detected as lower than controls in the first and second readings, and became better during L-thyroxin treatment. CONCLUSION: Our results indicate that some changes may occur on the hematic and biochemical analytes affecting the RBC deformability features. Neonates with CH have the worst rEI initially, but they reached the indices of the healthy infants thanks to L-thyroxin treatment. Also, their OF features have been improved by L-thyroxin.

Effect of carnosine on erythrocyte deformability in diabetic rats.

It is known that oxidative stress plays an important role in the chronic complications of diabetes. Lipid peroxidation is one of the consequences of oxidative stress. Erythrocyte deformability abilities are reduced as a result of lipid peroxidation. Conversely, a decrease nitric oxide (NO) production seems to be responsible in endothelial dysfunction which occurs in diabetic vascular complications. Carnosine is a molecule with anti-oxidant properties. The aim of this study was to investigate erythrocyte deformability indices and the effects of carnosine on erythrocyte deformability in diabetes and to determine a possible relationship between carnosine and nitric oxide. Male Wistar albino rats were used in the study. Injections were administered to seven groups consisting of eight rats each. The groups were: Control, Carnosine, L-NAME (NG-nitro-L-arginine methyl ester), Diabetic, STZ (Streptozotocin) +Carnosine, STZ+L-NAME and STZ+Carnosine+L-NAME. In addition, glucose, insulin, MDA (Malondialdehyde) and NO levels were measured and erythrocyte deformability indices were calculated in all groups. Erythrocyte deformability indices and NO levels were decreased and MDA levels were found to be increased in diabetic group. It was also found that carnosine can significantly reverse erythrocyte deformability, reduce lipid peroxidation and increase NO levels in diabetes. It can be concluded that carnosine can recover from microvascular circulation problems by increasing erythrocyte deformability, can protect cells and tissues against lipid peroxidation and can be used as a multi-functional anti-oxidant in the treatment of diabetes mellitus to prevent the complications of diabetes.

Biological understanding of the cardiovascular risk associated with major depression and panic disorder is important.

INTRODUCTION: Panic disorder (PD) and major depressive disorders (MDD) are serious mental disorders but the mechanisms underlying the pathophysiology are poorly understood. Nitric oxide (NO) is a gas considered to play an important role in mediating anxiety and stress response and is synthesised from nitric oxide synthase (NOS). The endothelial isoform (eNOS) has been found also in platelets. Homocysteine (Hcy) is an amino acid which naturally occurs in the human body. Elevated levels are linked to increased risk of cardiovascular, neurological and psychiatric diseases. In this study we aimed to evaluate NO, platelet aggregation and Hcy levels in PD and MDD patients. MATERIALS AND METHODS: Nineteen PD and 18 MDD patients participated in this study. NO levels were measured spectrophotometrically, platelet aggregation levels were measured in an aggregometer and Hcy levels were measured by HPLC. RESULTS: NO levels were significantly lower in patients with MDD and PD than in control subjects (P < 0.05). Hcy and platelet aggregation levels were significantly higher in patients with MDD and PD than in control subjects (P < 0.05). CONCLUSION: Further more detailed studies are needed to find out the effects of drugs on these parameters or to disclose the exact mechanism underlying the alteration of these parameters.

Electrophysiological evidence of biphasic action of carnosine on long-term potentiation in urethane-anesthetized rats.

Carnosine is a dipeptide synthesized by the carnosine synthetase from ß-alanine and l-histidine. The well-known effects of carnosine may be related with mechanisms producing long-term potentiation which is one of the electrophysiological signs of memory. In the present study we aimed to investigate the effect of four different doses of carnosine on long-term potentiation in urethane-anesthetized rat. A bipolar stimulating electrode was placed in the medial perforant path and a double-barrel glass micropipette was placed in the dentate gyrus as the recording electrode. Artificial cerebrospinal fluid (in the control group) or carnosine (0.1, 1, 10, and 100µg/µL) was infused into the dentate gyrus. Our results showed that the I/O curve of the excitatory postsynaptic potential slope or population spike amplitude was not significantly shifted by carnosine. We found that population spike amplitude increased to 244% and 287% at the dose of 100µg/µL in the post-tetanic and induction phases, respectively, but decreased to 163% and 186% at the dose of 0.1µg/µL and to 145% and 162% at the dose of 1µg/µL when compared with 203% and 232% of the control values. However, there were no significant differences for the slope of excitatory postsynaptic potential. Carnosine had no effect on the EPSP slope or PS amplitude recorded from the dentate gyrus in response to test stimuli when high-frequency stimulation was not delivered. In the present study, we speculated that the effects of carnosine in lower or higher doses could be explained by its effect on different processes, such as soluble guanylyl cyclase inhibition or the conversion of carnosine into histamine.

The effects of colorectally insufflated oxygen-ozone on red blood cell rheology in rabbits.

Currently, with reappraisal of ozone therapy, it has been utilized worldwide in research and clinical field. Most of the studies investigating effects of ozone on blood parameters are conducted by directly ozonating the blood. Rectal insufflation is a simple, easy and inexpensive method of delivering ozone. Little is known how these gases affect some fundamental hemorheologic parameters when given by insufflation. We aimed to investigate the effects of colorectally insufflated oxygen-ozone on red blood cell rheology in rabbits. Rabbits were divided into Group 1 (control); Groups 2, 3 and 4 (oxygen rectally insufflated respectively for 15, 21 and 36 days); Groups 5, 6 and 7 (ozone rectally insufflated respectively for 15, 21 and 36 days). Erythrocyte deformability, aggregation and osmotic fragility were determined from blood samples at the end of each treatment period. Our study showed an improvement in deformability, a decrease in aggregation and an increase in fragility following a 15 day ozone treatment. With longer ozone application the changes in aggregation and fragility returned back to control levels, however its effect on deformability sustained. Therefore, more than two weeks ozone insufflation may induce adaptation to changes induced by ozone suggesting its systemic effects.

Effects of carnosine on long-term plasticity of medial perforant pathway/dentate gyrus synapses in urethane-anesthetized rats: an in vivo model.

The objective of this study was to examine the effect of carnosine on the hippocampal-dependent learning in perforant pathway/dentate gyrus synapses. The experiments were carried out on adult rats. A bipolar stimulating electrode was placed to the medial perforant path and a double-barrel glass micropipette was placed in the dentate gyrus as the recording electrode. Artificial cerebrospinal fluid (to control group) or carnosine (0.1, 1 microg/microL) was infused into the dentate gyrus via one of the barrels of the glass electrode. Our results showed that the I/O curve of excitatory postsynaptic potential (EPSP) slope or population spike (PS) amplitude was not significantly shifted by carnosine. Although carnosine infused prior to high-frequency stimulation (HFS) decreased the slope of EPSP and amplitude of PS, when infused after HFS, no effect was observed. In the present study, we speculated that carnosine decreased LTP by inhibiting sGC activation. The present experiment provides the first evidence that carnosine may play a role in synaptic plasticity in dentate gyrus in vivo.

Impaired erythrocytes deformability in H(2)O(2)-induced oxidative stress: protective effect of L-carnosine.

Impaired red blood cell deformability is a hemorheological perturbation induced by many kinds of diseases. An increase in free radicals causes a reduction in erythrocyte flexibility and deformability. Carnosine is a dipeptide abundant in skeletal muscle and brain of humans. One of the main function of carnosine is its antioxidant and free-radical scavenger effect. In this study our aim is to investigate the protective effect of L-carnosine on RBCs in H(2)O(2)-induced oxidative stress in vitro conditions. Twenty male wistar albino rats, 10 were 3 months old, 10 were 12 months old used. The blood from each rat were divided into ten tubes and these blood samples divided into two groups. The first tube of the first group was the control and the rest 4 tubes were treated with different concentrations of L-carnosine. All tubes in the second group were incubated with H(2)O(2) additively. The deformability indexes of the erythrocytes were measured by a laser diffractometer (Myrenne Rheodyne SSD).L-carnosine has improved the RBC deformability significantly which is impaired by H(2)O(2) treatment (p<0.05). Increase in deformability is more significant in young rat group when compared to old rat group.L-carnosine, as an antioxidant molecules, has a dose dependent positive effect on RBC deformability and has improved or protect the deformability of erythrocytes, especially in young rat group which impaired by H(2)O(2)-induced oxidative stress in vitro conditions. The results of this study first suggest that L-carnosine supplemention can be used to improve the RBC quality or to protect them from oxidative damage in survival of RBC in the circulation.

Gender-related alerations in erythrocyte mechanical activities under desflurane or sevoflurane anesthesia.

Alterations in erythrocyte mechanical activities under the influence of anesthesia have been observed and discussed among the responsible factors for the deterioration of tissue and organ perfusion related to anesthetic procedures.21 female and 17 male Swiss Albino rats were used. Female (f) and male (m) rats were divided into 3 groups; control (f (n=7); m (n=5)), sevoflurane treated group (f (n=7); m (n=5)), desflurane treated group (f (n=7); m (n=7)). 2% of sevoflurane or 6% desflurane were applied to the rats with inhalation in an adjustable cage for one hour. The deformability indexes of the erythrocytes were measured by a laser diffractometer (Myrenne Rheodyne SSD). Sevoflurane anesthesia has improved the deformability of erythrocytes in male rats (p<0.05) whereas there were not any significant changes in female rats. Desflurane has improved the deformability of erythrocytes in both gender significantly (p<0.05). Volatil anesthetic agents sevofluran and desflurane has improved the mechanical properties of the erythrocytes in male rats compared to their controls. However, these changes were not significant with sevoflurane in females. The results in male rats may be due to the effects of testosterone on the flexibility of the erythrocytes leading them to tolerate to the environmental changes. These results reveal that the inhalation anesthetics like sevoflurane and desflurane are appropriate anesthetics which can improve the deformability of erythrocytes during surgery.

The importance of circadan rhythm alterations in erythrocyte deformability.

The hormone melatonin, secreted from the pineal gland at night and suppressed during the day, provides a circadian and seasonal signal to the organism. The impact of pharmacological doses of melatonin on erythrocyte deformability was investigated by our group in several studies in both in vitro and in vivo conditions. The aim of this study was to investigate the effects of alterations in the physiological melatonin levels via the circadian rhythm on erythrocyte deformability. 50 male rats weighing 250-300 g were divided in 5 groups. The rats were subjected to 12/12, 24/0, 0/24, 16/8 and 8/16 h of Light/Dark (L/D) cycle, respectively. The elongation indexes (EI) of the erythrocytes were measured by a laser diffractometer (Myrenne Rheodyne SSD) by using 30 microl of whole blood suspended in 2 ml of Dextran 60. There was no significant difference in the EI of the 24/0 h L/D group compared to the control (12/12), whereas the decrease of EI was statistically important in the 0/24 h L/D group (p = 0.009). This decrease in EI was also significant when this group was compared to the 24/0 h L/D group (p = 0.05). Furthermore, the EI was affected significantly by alterations in the circadian rhythm, compared to control (16/8, 8/16 h L/D; p = 0.05 and p = 0.007, respectively). As a result, the alterations in physiological melatonin levels via different circadian rhythms have significant impacts on the deformability of erythrocytes, which therefore may cause important cardiovascular implications in the people who are exposed to different light dark cycles. Furthermore, these data represents a new and a quite crucial open-field to be investigated and taken into account in in vivo hemorheological studies.

The red blood cell deformability alterations under desfluran anesthesia in rats.

General anesthesia, either with inhalation or through nonvolatile anesthetics, is known to affect the overall cardiovascular function as well as the microcirculatory hemodynamics. In this study, the effects of desfluran anesthesia on the red blood cell deformability of young and old rats are investigated. 33 male rats were used in the study and the rats were divided into two groups according to their age (young and old) comprising of two subgroups in each. First group was the young control (n = 5), the second was the young group treated with desfluran (n = 7), the third group was the old control (n = 7) and the last group was the old group treated with desfluran (n = 7). %6 of desfluran was applied to the rats with inhalation in an adjustable cage for one hour. The elongation indexes of the erythrocytes were measured by a laser diffractometer (Myrenne Rheodyne SSD). Deformability indexes of red blood cells were significantly increased with desfluran in young rats (p = 0.042) whereas they were significantly decreased in old rats (p = 0.004) with desfluran application compared with their controls. When we compared the young and old control groups, the deformability indexes were significantly higher in old ones (p < 0.001). However, there was no significant difference between the old and the young desfluran applied groups. The volatile anesthetic agent desfluran impairs the deformability of erythrocytes in old rats compared to their controls, whereas it has the opposite effects on young ones. This may be due to the alterations in membrane structure with age. These results reveal that the inhalation of anesthetics like desfluran may cause more serious problems in the elder people during the surgery and may influence their hemodynamic parameters.

The influence of sevoflurane anesthesia on the rat red blood cell deformability.

Alterations in blood rheology under the influence of anesthesia have been observed and discussed among the responsible factors for the deterioration of tissue and organ perfusion related to anesthetic procedures. Sevoflurane is one of the volatil anesthetics which is being used very common in surgery. In this study, the effects of sevoflurane anesthesia were investigated in different age groups of rats. 22 male rats were used in the study and the rats were divided into two groups according to their age (young and old) comprising of two subgroups in each. First group was the young control (n = 5), the second was the young group treated with sevoflurane (n = 5), the third group was the old control (n = 7) and the last group was the old group treated with sevoflurane (n = 5). %2 of sevoflurane was applied to the rats with inhalation in a adjustable cage for one hour. The deformability indexes of the erythrocytes were measured by a laser diffractometer (Myrenne Rheodyne SSD). Deformability indexes of red blood cells were significantly decreased with sevoflurane in old rats (p = 0.028) whereas it had not any significant effect in young group compared with their controls. When we compared the young and old control groups, the deformability indexes were significantly higher in old ones (p < 0.001). However, there were not any significant difference between the old and the young sevoflurane applied groups. A volatil anesthetic agent sevoflurane has impaired the deformability of erythrocytes in old rats compared to their controls, whereas it had not any significant effect in young ones which may be due to the flexibility of the young erythrocytes leading them to tolerate to the environmental changes. These results reveal that the inhalation anesthetics like sevoflurane may cause more serious problems in the elder people and their hemodynamic parameters should be checked more seriously during the surgery.

The in vivo antioxidant effectiveness of alpha-tocopherol in oxidative stress induced by sodium nitroprusside in rat red blood cells.

Reactive oxygen species avidly reacts with nitric oxide (NO) producing cytotoxic reactive nitrogen species capable of nitrating proteins and damaging other molecules which leads to the reduction of erythrocyte deformability. The aim of this investigation was to assess the importance of alpha-tocopherol (Vit-E) in the total antioxidant status of the erythrocytes in sodium nitroprusside (SNP), a nitric oxide donor, induced oxidative stress and its relation to erythrocyte deformability. Male Swiss Albino rats were used in 4 groups, comprising of 10 animals in each group. The first group was the control, and the other groups were administered SNP (10 mg/kg, i.p.), Vit-E (10 mg/kg, i.p.) + SNP, and SNP + L-NAME (10 mg/kg, i.p.), respectively. Relative filtration rate (RFR), relative filtration time (RFT) and relative resistance (Rrel) were determined as the indexes of erythrocyte deformability. In addition, malondialdehyde (MDA, as an index of lipid peroxidation) and nitric oxide levels and the antioxidant activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT) were also determined in the red blood cells of all groups revealing the oxidant-antioxidant activity. RFT and the Rrel of the erythrocytes of the SNP-treated rats increased significantly (p<0.05) whereas the RFR of the erythrocytes decreased (p<0.05) in comparison to all groups reflecting the impaired deformability. This reduction in RFR was prevented with both L-NAME or Vit-E incubation. Vit-E has also reduced the Rrel of the erythrocyte which reveals that it has improved the erythrocyte deformability. Lipid peroxidation was suppressed by Vit-E and L-NAME significantly, where the red blood cell deformability was improved. Furthermore, SOD and CAT activities were significantly stimulated with SNP treatment (p<0.05), where as GSH-Px remained unchanged. In the contrary, GSH-Px activity was triggered significantly by Vit-E administration, whereas the SOD and CAT activities were reduced (p<0.05). As a result, these data reveal that Vit-E improves the erythrocyte deformability in SNP-induced oxidative stress by its antioxidant effects on the lipid peroxidation and antioxidant enzyme activities.

In vitro effects of melatonin on the filtrability of erythrocytes in SNP-induced oxidative stress.

Erythrocyte deformability is one of the most important charactheristics of erythrocytes for an effective microcirculatory function and is affected from a number of factors, including the oxidative-damage-induced by nitric oxide (NO). This study was performed to investigate the effects of in vitro melatonin incubation on the antioxidant status and deformability of erythrocytes in sodium nitroprusside (SNP), a nitric oxide donor, induced oxidative stress. 40 blood samples taken from the adult healthy people were divided into 4 groups randomly and incubated with saline, SNP (1 mM), melatonin (MEL, 1 mM), MEL + SNP and SNP + L-NAME (5 mM) respectively. Relative filtration rate (RFR), relative filtration time (RFT) and relative resistance (Rrel) were determined as the indexes of erythrocyte filterability. In addition, malondialdehyde (MDA, as an index of lipid peroxidation) and the antioxidant activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT) were also determined in the red blood cells of all groups revealing the oxidant-antioxidant activity. RFT and the Rrel of the erythrocytes incubated with SNP increased significantly (p<0.05) whereas the RFR of the erythrocytes decreased (p<0.05) in comparison to all groups. This reduction in RFR was prevented with both L-NAME or MEL incubation. Furthermore, MEL was found to be significantly efficient in preventing the erythrocytes from lipid peroxidation in these groups. In addition, GSH-Px and SOD activities were elevated with SNP incubation reflecting the oxidative stress in erythrocytes, whereas the CAT activity remained unchanged. Melatonin has no significant effect on the GSH-Px and CAT activity but, it caused a significant decrease in SOD activity (p<0.05). These results reveal that, melatonin can protect the erythrocytes from impaired deformability in SNP-induced oxidative stress due to antioxidant effects as revealed by lipid peroxidation and antioxidant enzyme activities.

Lipid peroxidation and deformability of red blood cells in experimental sepsis in rats: The protective effects of melatonin.

Sepsis has been associated with a lipopolysaccharide (LPS) induced bacterial infection and causes biochemical, hemodynamic and physiological alterations in a system. Erythrocyte deformability is very critical for a microcirculatory system to function effectively. Hence, we were interested in examining the effects of a potent antioxidant, melatonin (Mel), on lipid peroxidation and deformability of eythrocytes in LPS-induced experimental sepsis. Male Swiss Albino rats were used in 6 groups, each group comprising of 10 animals. The first group was the control, and the other groups were administered LPS (10 mg/kg, i.p.), Mel (10 mg/kg, i.p.), LPS + L-NAME (5 mM, i.p.), Mel + LPS and Mel + LPS + L-NAME, respectively. Deformability of the RBCs decreased significantly (p < 0.05) in the LPS group in comparison to all other groups. This reduction was prevented with both L-NAME and Mel, but was not as significant as when administering L-NAME or Mel alone. This result was adversely seen in nitric oxide levels, i.e. RBCD was reduced when the NO levels were higher. Therefore in the Mel group the NO levels were reduced while the RBCD enhanced. In addition to these, as an index of lipid peroxidation, the Malondialdehyde levels were elevated in LPS groups whereas the deformability was reduced. This lipid peroxidation was suppressed by Mel and/or L-NAME significantly, where the RBCD was enhanced. These results show that, Melatonin can elevate the RBCD in experimental sepsis due to its nitric oxide scavenging activity and antioxidant effect as revealed by lipid peroxidation.