The impact of sericin on inflammation, oxidative stress, and lipid metabolism in female rats with experimental knee osteoarthritis.

OBJECTIVE: This study investigated the effects of sericin on inflammation, oxidative stress, and lipid metabolism in female rats with experimental knee osteoarthritis (KOA), focusing on evaluating its effectiveness via the sterol regulatory protein (SREBP)-1C and SREBP-2 pathways. METHODS: The rats were randomly assigned to three experimental groups: the C group (control), the KOA group (KOA control), and the sericin group (KOA + sericin). The KOA model was created by injecting monosodium iodoacetate (MIA) into the knee joint. Sericin was administered intra-articularly to rats on days 1, 7, 14, and 21 (0.8 g/kg/mL, 50 µL). After 21 days, the rats were sacrificed, and serum samples were analyzed using an ELISA to measure tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1ß), IL-10, SREBP-1c, SREBP-2, acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), cholesterol, triglyceride, and total oxidant-antioxidant status (TOS-TAS) levels. RESULTS: The KOA group exhibited higher serum TNF-α, IL-1ß, TOS, SREBP-1C, ACC, FAS, triglyceride, SREBP-2, and cholesterol levels than the C group (P < 0.05). However, the levels of these cytokines, except cholesterol, were significantly lower in the sericin group than in the KOA group. The KOA group exhibited significantly lower serum TAS and IL-10 levels than the C group (P < 0.05). In the sericin group, there was a statistically significant increase (P < 0.05). CONCLUSION: Sericin shows promising potential for reducing inflammation, oxidative stress, and lipid metabolism in experimental models of KOA in rats. However, further clinical research is necessary to validate the potential of sericin as a therapeutic agent for treating KOA. Key Points • Sericin can reduce knee osteoarthritis (KOA) symptoms in an experimental rat model. • In particular, in the serum of an experimental KOA rat model, sericin specifically reduces the levels of proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1ß), and increases the levels of anti-inflammatory cytokines, such as IL-10. • Sericin reduced lipid metabolism via the sterol regulatory protein (SREBP)-1C and SREBP-2 pathways and oxidative stress in the serum of the experimental KOA rat model. • The intra-articular administration of sericin has been shown to significantly reduce lipid metabolism, oxidative stress, and inflammation, as supported by biochemical analysis. These findings suggest its promising potential as an alternative treatment option for KOA.

HIIT serves as an efficient training strategy for basketball players by improving blood fluidity and decreasing oxidative stress.

BACKGROUND: A challenge for coaches and athletes is to find the best combination of exercises during training. Considering its favorable effects, HIIT has been very popular recently. OBJECTIVE: The goal of this study was to investigate anthropometric features, performance, erythrocyte deformability, plasma viscosity (PV) and oxidative stress in response to acute and long-term (6 weeks) HIIT in adolescent basketball players. METHODS: 22 sportsmen between the ages of 14-16 were included. Tabata protocol was applied to the HIIT group in addition to their routine training program 3 days/week, for 6 weeks. Erythrocyte deformability was determined using an ectacytometer (LORCA), PV with a rotational viscometer. Total oxidant status (TOS), total antioxidant status (TAS) were measured by kits. RESULTS: HIIT for 6 weeks induced an improvement in performance tests and waist circumference. 6 weeks of HIIT resulted in a decrement, while the last exercise session yielded an increment in RBC deformability. PV and TOS of HIIT groups were decreased on the 6th week. CONCLUSIONS: Our results demonstrate that, HIIT in addition to the routine exercise program is beneficial for improving performance and blood fluidity as well as decreasing oxidative stress in basketball players. Therefore, HIIT seems as an efficient training strategy for highly-trained individuals.

Anti-inflammatory effects of sericin and swimming exercise in treating experimental Achilles tendinopathy in rat.

The aim of this study was to assess the effectiveness of combining sericin with swimming exercise as a treatment for type-I collagenase-induced Achilles tendinopathy (AT) in rats, with a focus on inflammatory cytokines. An experimental AT model was established using type-I collagenase in male Sprague-Dawley rats, categorized into five groups: Group 1 (Control + Saline), Group 2 (AT), Group 3 (AT + exercise), Group 4 (AT + sericin), and Group 5 (AT + sericin + exercise). Intratendinous sericin administration (0.8 g/kg/mL) took place from days 3 to 6, coupled with 30 min daily swimming exercise sessions (5 days/week, 4 weeks). Serum samples were analyzed using ELISA for tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1ß), interleukin-10 (IL-10), and total antioxidant-oxidant status (TAS-TOS), alongside histopathological and immunohistochemical assessments of Achilles tendon samples. Elevated TNF-α and IL-1ß and decreased IL-10 levels were evident in Group 2; Of these, TNF-α and IL-1ß were effectively reduced and IL-10 increased across all treatment groups, particularly groups 4 and 5. Serum TAS was notably lower in Group 2 and significantly increased in Group 5 compared to Group 2. Histopathologically, Group 2 displayed severe degeneration, irregular fibers, and round cell nuclei, while Group 5 exhibited decreased degeneration and spindle-shaped fibers. The Bonar score increased in Group 2 and decreased in groups 4 and 5. Collagen type-I alpha-1 (Col1A1) expression was notably lower in Group 2 (P = 0.001) and significantly increased in groups 4 and 5 compared to Group 2 (P = 0.011 and 0.028, respectively). This study underscores the potential of sericin and swimming exercises in mitigating inflammation and oxidative stress linked to AT pathogenesis, presenting a promising combined therapeutic strategy.

Silk protein sericin: a promising therapy for Achilles tendinopathy-evidence from an experimental rat model.

OBJECTIVE: This study investigated the efficacy of sericin in treating experimental Achilles tendinopathy (AT) in rats via the transforming growth factor-beta (TGF-ß)/mothers against decapentaplegic (Smad) pathway compared with diclofenac sodium (DS). METHOD: An AT model was induced in rats using collagenase enzyme type I and divided into 5 groups: C (control), AT (diseased control), ATS (AT treated with sericin), ATN (AT treated with DS), and ATSN (AT treated with sericin and DS). Sericin injection was given on the 3rd and 6th days by intratendinous injection (0.8 g/kg/mL), and DS was administered for 14 days by oral gavage (1.1 mg/kg/day). Serum concentrations of total oxidant-antioxidant status (TOS-TAS), TGF-ß1, decorin, Smad2, and connective tissue growth factor (CTGF) were measured. Histopathologic and immunohistochemical (IHC) studies were conducted on Achilles tendon samples. RESULTS: The TOS, oxidative stress index (OSI), TGF-ß1, Smad2, CTGF, and decorin serum concentrations were significantly higher in AT than in C and significantly lower in ATS than in AT (P<0.05). Histopathological examination revealed that irregular fibers, degeneration, and round cell nuclei were significantly elevated in AT. Spindle-shaped fibers were similar to those in C, and degeneration was reduced in ATS. TGF-ß1 and Smad2/3 expression was increased, and collagen type I alpha-1 (Col1A1) expression was decreased in AT vs. C (P=0.001). In the ATS, TGF-ß1 and Smad2/3 expression decreased, and Col1A1 expression increased. The Bonar score significantly increased in the AT group (P =0.001) and significantly decreased in the ATS group (P =0.027). CONCLUSION: Sericin shows potential efficacy in reducing oxidative stress and modulating the TGF-ß/Smad pathway in experimental AT models in rats. It may be a promising therapeutic agent for AT, warranting further clinical studies for validation. Key Points • This study revealed that sericin mitigates AT-induced damage through the TGF-ß/Smad pathway in an AT rat model. • ELISA and IHC investigations corroborated the effectiveness of sericin via the pivotal TGF-ß/Smad pathway in tissue repair. • Evidence indicates that sericin enhances collagen synthesis,shapes tendon fiber structure, and diminishes histopathological degeneration. • Sericin's antioxidant properties were reaffirmed in its AT treatment application.

Determination of the pathways of potential muscle damage and regeneration in response to acute and long-term swimming exercise in mice.

The objective of the current study was examining early and late (3, 24 h) responses to acute, chronic swimming exercise as muscle damage and regeneration in gastrocnemius-soleus muscle complexes. We also aimed to reveal the signaling pathways involved. 8-12 weeks old mice were grouped as control, exercise. Exercising groups were firstly divided into two as acute and chronic, later every group was again divided in terms of time (3, 24 h) passed from the last exercise session until exsanguination. Acute exercise groups swam 30 min, while chronic swimming groups exercised 30 min/day, 5 days/week, 6 weeks. Histological investigations were performed to determine muscle damage and regeneration. Whole-genome expression analysis was applied to total RNA samples. Microarray data was confirmed by quantitative real-time PCR. Exercising mice muscle revealed enhanced damage, leukocyte infiltration. Increments in acute and chronic 3 h groups were statistically significant. Car3, Neb, Obscn, Ttn, Igfbp5, Igfbp7, Gsk3ß, and Usp2 were down-regulated in muscles of swimming mice. The exercise-induced signaling pathways involved in muscle damage and regeneration were drawn. Our findings demonstrate that swimming induces muscle damage. Samples were obtained at 3 and 24 h following exercise, this time duration seems not sufficient for the development of myofibrillogenesis.

Hemorheology and oxidative stress in patients with differentiated thyroid cancer following I-131 ablation/metastasis treatment.

BACKGROUND: Although radioiodine theraphy (RAIT) is thought to affect blood cells and oxidative stress, hemorheological alterations following dose-dependent RAIT remains unknown. OBJECTIVE: The aim of this study was to determine the effects of RAIT on hemorheological and oxidative stress parameters in patients with differentiated thyroid cancers (DTC). METHODS: Totally 31 DTC patients (mean age 46.32±11.15 years) and 26 healthy controls (mean age 50.50±6.22 years) were included. Venous blood samples were collected from each patient before and after treatment (7th day, 1th month and 6th month). Erythrocyte aggregation-deformability and oxidative stress parameters were determined. p < 0.05 was considered as statistically significant. RESULTS: Erythrocyte deformability of the patients determined at 16.87 and 30 Pascal were significantly lower than healthy individuals. Erythrocyte aggregation index (AI) of the patients was higher, whereas erythrocyte aggregation half-time (t½) was lower compared to control. Erythrocyte deformability values and AI were not significantly different from the pre- and post-radioiodine treatment groups. There was no statistically significant difference between the oxidative stress parameters before and after the treatment. CONCLUSIONS: Patients were in a worse hemorheological condition compared to healthy individuals. After RAIT, RBC deformability and aggregation were not affected and no significant change in oxidative stress parameters was detected.

Investigation of the effects of major ozone autohemotherapy application on erythrocyte deformability and aggregation.

BACKGROUND: Ozone is used intensively worldwide in treatment and research of various pathologies due to its healing effects. OBJECTIVE: The aim of this study is to investigate the effect of major ozone autohemotherapy on erythrocyte deformability and aggregation. METHODS: 10 and 50µg/ml doses of ozone was applied for 20 minute to venous blood samples obtained from 10 healthy male volunteers. Erythrocyte aggregation, deformability were measured by an ektacytometer. Total oxidant status, total antioxidant status were measured via a commercial kit. The oxidative stress index was calculated. RESULTS: Ozone at 10 and 50µg/ml doses did not alter erythrocyte aggregation. 50µg/ml ozone increased red blood cell (RBC) deformability measured at 0.53 Pa. Compared with the Control value, there was a significant increase in TOS, TAS for the doses of 10 and 50µg/ml. The increase in TAS was found to be more significant at 10µg/ml dose. The most obvious increase in OSI value was observed at 50µg/ml. CONCLUSION: Our results demonstrate that although 10µg/ml ozone has no effect on hemorheology, 50µg/ml ozone concentration has positive effects on RBC deformability, thus circulation at 0.53 Pa corresponding to the shear stress encountered during venous circulation.

Hemorheological alterations following an acute bout of nordic hamstring exercise in active male participants1.

BACKGROUND: The Nordic hamstring exercise (NHE) has been proven to be an effective preventive technique for hamstring injuries. Hemorheological parameters (erythrocyte deformability and aggregation) play a critical role in exercise influencing oxygenation. Although previous studies presented hemorheological alterations induced by different types of exercise, changes in red blood cell (RBC) deformability and aggregation following NHE remain unknown. Present study was designed to explore possible alterations in hemorheological and oxidative parameters after an acute bout of NHE. METHODS: 10 healthy, male, active students (mean age 19.9±0.23, BMI: 21.56±0.54) participated to the study. They performed a single session of seven-repetitions of NHE followed by a familiarisation period. Blood samples were obtained before and immediately after the exercise from the antecubital vein. Hemorheological parameters were measured by an ektacytometer. RESULTS: NHE did not change deformability, hematocrit and oxidative stress but, increased RBC aggregation index (AI, p = 0.011) and decreased RBC aggregation half time (t½, p = 0.009). CONCLUSIONS: Our results suggest that, increased RBC aggregation following an acute bout of NHE may result in increased plasma skimming and thus ease the flow of blood.

Increased erythrocyte aggregation following an acute bout of eccentric isokinetic exercise does not exceed two days.

BACKGROUND: Isokinetic exercise is used to reduce strength imbalance and to enhance performance. OBJECTIVE: The aim of this study was to investigate the acute effects of a single bout of eccentric isokinetic exercise on hemorheology (erythrocyte deformability and aggregation), total oxidant/antioxidant status (TOS/TAS) and oxidative stress index (OSI) in active individuals. METHODS: The study comprises 11 active, healthy, male subjects (mean age of 19.45 ± 0.31 years, BMI 22.05 ± 0.51 kg/m2). They performed single, unilateral eccentric contractions of knee flexors and extensors with dominant leg on a dynamometer. Isokinetic hamstring, quadriceps strength were recorded at eccentric (30, 120° s-1) angular velocities. Eight active age-matched healthy male subjects were included as a control group, who did not receive exercise. Blood samples were obtained before, immediately after and two days after the exercise session. Hemorheological parameters were measured by an ektacytometer. TOS/TAS were determined using a commercial kit. RESULTS: A session of eccentric isokinetic exercise did not affect erythrocyte deformability and oxidative stress indices, whereas red blood cell (RBC) aggregation was increased initially and returned to pre-exercise levels after two days following exercise. CONCLUSION: Our results suggest that, increased RBC aggregation following an acute bout of isokinetic exercise may result in increased plasma skimming that augments tissue perfusion and clearance of metabolites within a period of two days following exercise.

Contribution of Heme Oxygenase 2 to Blood Pressure Regulation in Response to Swimming Exercise and Detraining in Spontaneously Hypertensive Rats.

BACKGROUND We aimed to determine the effects of exercise followed by detraining on systolic blood pressure (SBP), heme oxygenase 2 (HO-2) expression, and carboxyhemoglobin (COHb) concentration in spontaneously hypertensive rats (SHR) to explain the role of carbon monoxide (CO) in this process. MATERIAL AND METHODS Animals were randomized into exercised and detrained groups. Corresponding sedentary rats were grouped as Time 1-2. Swimming of 60 min/5 days/week for 10 weeks was applied. Detraining rats discontinued training for an additional 5 weeks. Gene and protein expressions were determined by real-time PCR and immunohistochemistry. RESULTS Aorta HO-2 histological scores (HSCORE) of hypertensive rats were lower, while SBP was higher. Swimming caused enhancement of HO-2 immunostaining in aorta endothelium and adventitia of SHR. Exercise induced elevation of blood COHb index in SHR. Synchronous BP lowering effect of exercise was observed. HO-2 mRNA expression, HSCORE, and blood COHb index were unaltered during detraining, while SBP was still low in SHR. CONCLUSIONS CO synthesized by HO-2 at least partly plays a role in SBP regulation in the SHR- and BP-lowering effect of exercise. Regular exercise with short-term pauses may be advised to both hypertensives and individuals who are at risk.

Impaired Hemorheology in Exacerbations of COPD.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterized by progressive airflow limitation. Cardiovascular-related comorbidities are established to contribute to morbidity and mortality especially during exacerbations. The aim of the current study was to determine alterations in hemorheology (erythrocyte aggregation, deformability) in newly diagnosed COPD patients and their response to medical treatment and to compare with values of COPD patients with exacerbations. MATERIALS AND METHODS: The study comprised 13 COPD patients, 12 controls, and 16 COPD patients with exacerbations. The severity of COPD was determined according to Global Initiative for Chronic Obstructive Lung Disease guidelines. Red blood cell (RBC) deformability and aggregation were measured by an ektacytometer. RESULTS: RBC deformability of COPD patients with exacerbations was decreased compared to the other groups. Erythrocyte aggregation and plasma fibrinogen of COPD patients determined during exacerbations were higher than control. CONCLUSION: Decreased RBC deformability and increased aggregation associated with exacerbations of COPD may serve as unfavorable mechanisms to worsen oxygenation and thus clinical symptoms of the patient. Treatment modalities that modify rheological parameters might be beneficial.

Increased erythrocyte aggregation in patients with primary open angle glaucoma.

BACKGROUND: The rationale of this study is to determine alterations in blood rheology (erythrocyte aggregation and deformability) and relationship between structural measurements obtained from optical coherence tomography (OCT) in different stages of primary open angle glaucoma (POAG). METHODS: This prospective controlled study comprised 23 POAG patients (glaucoma group) and 23 age- and sex-matched healthy subjects (control group). Elongation index (EI), which is the indicator of erythrocyte deformability and erythrocyte aggregation was measured using an ektacytometer. Optic nerve head (ONH) morphology and peripapillary retinal nerve fibre layer (RNFL) thickness were evaluated using a spectral domain (SD) OCT. RESULTS: There were no significant differences between the groups regarding the elongation index values (p > 0.05). On the other hand, erythrocyte aggregation amplitude (AMP) and mean corpuscular haemoglobin concentration (MCHC) were significantly higher in the glaucoma group than in the control group (p = 0.015, p = 0.003 respectively). A significant correlation was also found between the elongation index and retinal nerve fibre layer (average and superior) thickness (p < 0.05) in patients with late glaucoma. CONCLUSIONS: In patients with POAG, erythrocyte aggregation appears to be higher. It can be speculated that higher erythrocyte aggregation and deformability may be involved in the pathogenesis of glaucoma by affecting microperfusion of the optic nerve head and retina. Modification of rheological parameters in patients with glaucoma may be considered as an adjuvant future therapy in glaucoma management, whereas further studies in larger groups are needed.

Impaired Hemorheological Parameters and Increased Carotid Intima-Media Thickness in Children with Subclinical Hypothyroidism.

BACKGROUND: Subclinical hypothyroidism (SH) is defined as elevated serum thyroid-stimulating hormone (TSH) concentration associated with normal serum-free thyroxine levels. Effects of hypothyroidism on hemorheology had widely attracted the attention of researchers during the last decade. OBJECTIVE: The purpose of this study is to determine alterations in hemorheological parameters and carotid intima-media thickness (CIMT) in children with SH. METHODS: Fifty-three SH children and 31 healthy controls were enrolled. Erythrocyte deformability and aggregation were determined by an ektacytometer and plasma viscosity (PV) by a cone-plate rotational viscometer. CIMT was evaluated sonographically. RESULTS: Erythrocyte deformability of the SH group measured at 0.53 and 1.69-30 Pa was lower than that of the control group. The erythrocyte aggregation index, aggregation half time and PV were not different between the groups. However, the aggregation amplitude and mean corpuscular hemoglobin concentration were significantly higher in SH compared to the control group. There was a negative correlation between TSH and deformability values measured at 5.33-30.0 Pa. CIMT in patients with SH was significantly higher than in the control group (p = 0.001; SH = 0.48 ± 0.04 mm, control group = 0.43 ± 0.03 mm). CONCLUSION: Impaired hemorheology and increased CIMT are well-known risk factors for developing cardiovascular pathologies. The results of the current study suggest the treatment of children with SH in order to avoid early circulatory problems.

Increased erythrocyte aggregation and oxidative stress in patients with idiopathic interstitial pneumonia.

BACKGROUND: Hemorheological properties are important determinants of tissue oxygenation. Although hemorheological alterations in various lung diseases have been well-defined, no information is available about the effects of idiopathic interstitial pneumonia (IIP) on hemorheological parameters. OBJECTIVES: The aim of this study was to investigate hemorheological parameters (erythrocyte deformability, aggregation, and plasma viscosity -PV) and associated oxidative stress indices in patients with IIP. METHODS: The study enrolled 31 patients (9 Idiopathic pulmonary fibrosis (IPF), 10 non-specific Interstitial Pneumonia (NSIP), 12 Cryptogenic Organising Pneumonia (COP) and 33 healthy controls. Erythrocyte deformability and aggregation were measured by an ektacytometer. PV was determined by a cone-plate rotational viscometer and oxidative stress via a commercial kit. RESULTS: Erythrocyte aggregation, total oxidant status (TOS) and oxidative stress index (OSI) of IIP patients were higher than controls whereas erythrocyte deformability, PV and total antioxidant status (TAS) were unaltered. CONCLUSIONS: Increment of oxidative stress in IIP seems to depend on enhancement of oxidants, rather than alteration of antioxidants. The issue that, elevated erythrocyte aggregation may further impair tissue oxygenation by disturbing microcirculation in IIP, may be considered in the follow up and development of new treatment protocols for this disease.

Detraining reverses exercise-induced improvement in blood pressure associated with decrements of oxidative stress in various tissues in spontaneously hypertensive rats.

This study aimed to investigate the effects of moderate intensity swimming exercise (10 weeks) followed by detraining (for five and 10 weeks) on oxidative stress levels of heart, lung, kidney, and liver tissues and systolic blood pressure (SBP) of spontaneously hypertensive rats (SHR). SHR and control rats were randomized into sedentary, exercised, detrained (5 weeks) and late-detrained (10 weeks) groups. Corresponding sedentary rats were grouped as time 1-2-3. Exercise of 60 min, 5 days/week/10 weeks was applied. Detraining rats underwent the same training protocol and then discontinued training during next 5, 10 weeks. SBP was measured by tail-cuff method. Tissue total oxidant/antioxidant status was measured using a commercial kit and oxidative stress index (OSI) was calculated. Exercise training slightly decreased tissue OSI of SHR and reduced SBP of both groups. Tissue OSI of SHR were higher than WKY and aging resulted in increment of oxidants in groups. detraining yielded time-dependent increments in oxidative stress of all tissues and SBP of both rat groups. Although short-term cessations may be tolerated, our results emphasize the importance of exercising as a way of life for cardiovascular well-being in hypertensives or in individuals who are genetically under risk of hypertension.

Investigation of hemorheological parameters at the diagnosis and follow up of children with iron deficiency anemia and mixed anemia.

OBJECTIVE: We aimed to investigate the effects of iron deficiency anemia (IDA) and vitamin B12 deficiency coexisting with IDA which is called as mixed anemia (MA) on hemorheological parameters, to compare them with each other and healthy controls, and to assess the changes in hemorheological parameters after treatment. MATERIALS AND METHODS: 32 IDA patients (mean age:6.3 ± 5.3 years), 30 MA patients (mean age:7.2 ± 5.4 years), and 31 healthy controls (mean age:7.1 ± 5.2 years) were enrolled. Erythrocyte deformability and aggregation were determined by an ectacytometer, plasma and whole blood viscosities by a cone-plate rotational viscometer. Differences between IDA and MA, and healthy controls were compared. Hemorheological parameters were repeated in the patient groups after treatment and compared with the initial results. RESULTS: In both of the patient groups, erythrocyte deformability, whole blood and plasma viscosities were found to be significantly decreased before treatment, compared with the controls. After treatment these parameters were found to be increased significantly. There were no significant differences in these parameters between the IDA and MA group. Additionally, no statistically significant alteration was found in erythrocyte aggregation measurements of both patient groups. CONCLUSION: This study indicates that IDA and MA have similar effects on hemorheological parameters. When vitamin B12 deficiency accompanies IDA which is called as MA, no further alterations occur in hemorheological parameters. The adequate treatment of these anemias not only corrects the hematological parameters, but also by helping to normalize the hemorheological parameters, may contribute to the regulation of microvascular perfusion.

Investigation of hemorheological parameters at the diagnosis and the follow-up of nutritional vitamin B12 deficient children.

We aimed to investigate the effects of vitamin B12 deficiency on hemorheological parameters, and the changes in these parameters following vitamin B12 treatment. 33 patients (mean-age:7 ± 5.7 years) diagnosed as nutritional vitamin B12 deficiency, and 31 age and sex matched controls (mean-age:7.1 ± 5.2 years) were enrolled. Erythrocyte deformability and aggregation were determined by an ectacytometer, plasma and whole blood viscosities by a cone-plate rotational viscometer. The differences between patients and controls were compared. Hemorheological parameters were repeated in the patient group following vitamin B12 treatment, and the results were compared with the initial results. In vitamin B12 deficiency, erythrocyte deformability and whole blood viscosity were found to be significantly decreased, eythrocyte aggregation was found to be significantly increased compared with the controls. Plasma viscosity was found to be decreased in deficiency but this decrease was not statistically significant. In patient group, erythrocyte deformability, whole blood and plasma viscosities were found to be significantly increased and erythrocyte aggregation was significantly decreased, after treatment. This study indicates that vitamin B12 deficiency has important effects on hemorheological parameters and adequate treatment of deficiency not only corrects the hematological parameters, but also by helping to normalize the hemorheological parameters, may contribute to the regulation of microvascular perfusion.

Acute effects of Yo-Yo intermittent recovery test level 1 (Yo-YoIR1) on hemorheological parameters in female volleyball players.

In the present study, we investigated possible alterations in red blood cell (RBC) deformability, plasma and whole blood viscosities (WBV) and hematological parameters in response to Yo-Yo intermittent recovery test level 1 (Yo-YoIR1) which is currently used to assess endurance performance, in female volleyball players. Eight volleyball player volunteers from Pamukkale University (mean age19,9 ± 2,2 years; mean body height 177.5 ± 1.99 cm; mean body mass index 21.66 ± 0.64 kg/m2) participated to the study. Blood samples were collected before and immediately after test. Red blood cell (RBC) deformability was determined by ektacytometer, plasma and whole blood viscosities (WBV) by a cone-plate rotational viscometer. Hematological parameters were determined using an electronic hematology analyzer. The Yo-YoIR1 applied, induced acute increments in WBV at native hematocrit (Hct) measured at a shear rate of 150 s-1 and 375 s-1, RBC deformability and WBC count. The results of the current study indicate that, the Yo-Yo IR1 test used to determine physical capacity of the player, by resulting in increments in RBC deformability contributes blood flow and thus, athletic performance of the individual.

Exercise training and detraining modify hemorheological parameters of spontaneously hypertensive rats.

BACKGROUND: Hemorheological responses to swimming exercise have never been investigated in spontaneously hypertensive rats (SHR). OBJECTIVE: We aimed to investigate the effects of moderate intensity swimming exercise followed by detraining on erythrocyte deformability and aggregation in SHR. METHODS: SHR and WKY rats were randomized into sedentary, exercised, detrained (5 weeks) and late detrained (10 weeks) groups. Swimming exercise of 60 min, 5 days/week, 10 weeks was applied. Systolic blood pressure (SBP), heart rate, body weights were measured every 2 weeks. Erythrocyte deformability and aggregation were determined by ektacytometry. RESULTS: Exercise training reduced SBP in both WKY and SHR rats and decreased erythrocyte aggregation in SHR group. SBP lowering effect of exercise was maintained until a detraining period equal to the duration of the exercise protocol, while 5 weeks of detraining reverted the improvements observed in erythrocyte aggregation of hypertensive rats. Although exercise training did not affect erythrocyte deformability, detraining for 10 weeks decreased RBC deformability in normotensive, but not in hypertensive rats. CONCLUSIONS: It can be suggested that, the exercise training applied herein has favorable effects on circulation not only by lowering blood pressure, but also by decreasing erythrocyte aggregation which are reversed after 5 weeks of detraining in SHR.

Acute effects of continuous and intermittent aerobic exercises on hemorheological parameters: a pilot study.

BACKGROUND: Acute hemorheological responses to different types of aerobic exercises have never been compared in a single study in healthy people. OBJECTIVE: We aimed to compare acute effects of high intensity intermittent exercise (HIIE) and moderate intensity continuous exercise (MICE) on hemorheological parameters, in healthy young subjects. METHODS: A total of 34 sedentary young adults (12 males, 22 females) with a mean age of 20.0 ± 2.1 years were randomly assigned to HIIE, MICE or non-exercise groups. MICE exercised at the power corresponding to 50% of heart rate reserve (HRR) continuously for 25 min. HIIE exercised at the power corresponding to 100% of HRR for 30 s followed by 30 s rest for 25 min. The non-exercise group rested. Blood samples were collected before and after exercise and studied for blood count, whole blood viscosity (WBV), plasma viscosity (PV) and red blood cell (RBC) elongation at nine different shear stresses. RESULTS: WBV, PV, RBC elongation of MICE and HIIE groups were not found to be statistically different from each other or from the non-exercise group. Compared to the non-exercise group, there was a significant increase in white blood cell (WBC) and RBC counts in the MICE group. CONCLUSIONS: Different types of aerobic exercises, namely MICE, HIIE are not different from each other in terms of hemorheological parameters immediately after exercise.