Increased systemic oxidative stress in patients with keratoconus

PurposeTo establish the effect of systemic oxidative stress on the pathogenesis of keratoconus by measuring serum total oxidant status (TOS) and total antioxidant status (TAS) in patients with keratoconus.MethodsTwenty-five patients with keratoconus (keratoconus group) and 25 age-sex-matched healthy subjects (control group) were enrolled in the study. Exclusion criteria were smoking habit, history of any other corneal pathology, systemic disease or inflammation, and current antioxidant or anti-inflammatory therapies. All participants underwent a detailed ophthalmological examination and corneal topography. Serum samples were obtained from all participants. Oxidative stress markers (TAS and TOS) were measured using a commercial kit and oxidative stress index (OSI) was calculated.ResultsThe study comprised 25 patients with keratoconus (mean age of 26.4±1.7 years) and 25 healthy control subjects (mean age of 26.6±1.7 years) (P>0.05). The serum TOS and OSI values were significantly higher in patients with keratoconus compared with those of the controls (P=0.036 and 0.037, respectively). However, serum TAS did not show significant difference between the keratoconus and control groups (P=0.497).ConclusionsThe higher levels of serum oxidant status and OSI in patients with keratoconus suggest that systemic oxidative stress might be involved in the pathogenesis of keratoconus. © 2014 Macmillan Publishers Limited

spontaneously hypertensive rats

BACKGROUND: Hemorheological responses to swimming exercise have never been investigated in spontaneously hypertensive rats (SHR)

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

Increased systemic oxidative stress in patients with keratoconus.

PURPOSE: To establish the effect of systemic oxidative stress on the pathogenesis of keratoconus by measuring serum total oxidant status (TOS) and total antioxidant status (TAS) in patients with keratoconus. METHODS: Twenty-five patients with keratoconus (keratoconus group) and 25 age-sex-matched healthy subjects (control group) were enrolled in the study. Exclusion criteria were smoking habit, history of any other corneal pathology, systemic disease or inflammation, and current antioxidant or anti-inflammatory therapies. All participants underwent a detailed ophthalmological examination and corneal topography. Serum samples were obtained from all participants. Oxidative stress markers (TAS and TOS) were measured using a commercial kit and oxidative stress index (OSI) was calculated. RESULTS: The study comprised 25 patients with keratoconus (mean age of 26.4±1.7 years) and 25 healthy control subjects (mean age of 26.6±1.7 years) (P>0.05). The serum TOS and OSI values were significantly higher in patients with keratoconus compared with those of the controls (P=0.036 and 0.037, respectively). However, serum TAS did not show significant difference between the keratoconus and control groups (P=0.497). CONCLUSIONS: The higher levels of serum oxidant status and OSI in patients with keratoconus suggest that systemic oxidative stress might be involved in the pathogenesis of keratoconus

glaucoma

BackgroundThe 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).MethodsThis 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.ResultsThere 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.ConclusionsIn 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

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

Apelin-induced hemorheological alterations in DOCA-salt hypertensive rats.

Apelin is a hypotensive peptide. Red blood cell (RBC) deformability and aggregation were previously demonstrated to be altered in various hypertension (HT) models. In the present study, we investigated possible alterations in RBC deformability and aggregation in response to apelin in DOCA-salt hypertensive rats. Rats were randomly divided into 4 groups: Control (C), Hypertension (HT), Apelin, and Apelin + Hypertension (Apelin + HT). HT was induced by injection of DOCA-salt (25 mg/kg, s.c.) twice weekly for 4 weeks, whereas apelin was administered (200 μg/kg i.p.) for 17 days. RBC deformability and aggregation were determined using an ektacytometer. Blood pressure was monitored using a tail cuff system. Systolic blood pressure was decreased in the Apelin and Apelin + HT groups and increased in the HT group. RBC deformability was not significantly altered in the HT group. Apelin administration induced a statistically significant increase in RBC deformability in control animals, whereas erythrocytic deformability in the Apelin + HT group was decreased compared to the Apelin group. RBC aggregation of hypertensive animals was reduced compared to controls. Apelin administration induced increased RBC aggregation in hypertensive rats. Our results showed favorable effects of apelin on RBC deformability in control animals, but not in hypertensive rats