Effect of Garlic Extract on the Erythrocyte as a Simple Model Cell.

Garlic is known to have diverse effects on mammalian cells, being cytotoxic, especially to cancer cells, but also protect against oxidative stress. Mammalian erythrocyte is a simple cell devoid of intracellular organelles, protein synthesis ability, and most signaling pathways. Therefore, examination of the effects of garlic on erythrocytes allows for revealing primary events in the cellular action of garlic extract. In this study, human erythrocytes or erythrocyte membranes were exposed to garlic extract at various dilutions. Hemoglobin oxidation to methemoglobin, increased binding of hemoglobin to the membrane, and formation of Heinz bodies were observed. Garlic extract depleted acid-soluble thiols, especially glutathione, and induced a prooxidative shift in the cellular glutathione redox potential. The extract increased the osmotic fragility of erythrocytes, induced hemolysis, and inhibited hemolysis in isotonic ammonium chloride, indicative of decreased membrane permeability for Cl- and increased the membrane fluidity. Fluorescent probes indicated an increased level of reactive oxygen species and induction of lipid peroxidation, but these results should be interpreted with care since the extract alone induced oxidation of the probes (dichlorodihydrofluorescein diacetate and BODIPY C11). These results demonstrate that garlic extract induces oxidative changes in the erythrocyte, first of all, thiol and hemoglobin oxidation.

Protective Effect of Polyphenolic Extracts from Hippophae rhamnoides L. and Reynoutria japonica Houtt. on Erythrocyte Membrane.

Sea buckthorn and Japanese knotweed are known in many traditional medicine systems to be a great source of bioactive substances. This research aims to compare the bioactivity and protective effects of the phenolic extracts of leaves from sea buckthorn and roots and leaves from the Japanese knotweed on erythrocytes. The polyphenol composition of the extract was analyzed using UPLC-PDA-ESI-MS/MS. The extracts' toxicity and impact on the erythrocytes' osmotic fragility were measured spectrophotometrically. The antioxidant activity was determined based on the inhibition of oxidation of erythrocytes and their membrane induced by 2,2'-Azobis(2-methylpropionamidine) dihydrochloride (AAPH),measured spectrophotometrically and using fluorimetry. To find the possible mechanism of the extracts' action, extract-modified cells were observed under a microscope, and the potential localization of the extract's phytochemical composition was checked using fluorescent probes. The results showed that the used extracts are not toxic to erythrocytes, increase their osmotic resistance, and successfully protect them against free radicals. Extract components localize on the outer part of the membrane, where they can scavenge the free radicals from the environment. Altogether, the presented extracts can greatly protect living organisms against free radicals and can be used to support the treatment of diseases caused by excess free radicals.

Acrolein Induces Changes in Cell Membrane and Cytosol Proteins of Erythrocytes.

High concentrations of acrolein (2-propenal) are found in polluted air and cigarette smoke, and may also be generated endogenously. Acrolein is also associated with the induction and progression of many diseases. The high reactivity of acrolein towards the thiol and amino groups of amino acids may cause damage to cell proteins. Acrolein may be responsible for the induction of oxidative stress in cells. We hypothesized that acrolein may contribute to the protein damage in erythrocytes, leading to the disruption of the structure of cell membranes. The lipid membrane fluidity, membrane cytoskeleton, and osmotic fragility were measured for erythrocytes incubated with acrolein for 24 h. The levels of thiol, amino, and carbonyl groups were determined in cell membrane and cytosol proteins. The level of non-enzymatic antioxidant potential (NEAC) and TBARS was also measured. The obtained research results showed that the exposure of erythrocytes to acrolein causes changes in the cell membrane and cytosol proteins. Acrolein stiffens the cell membrane of erythrocytes and increases their osmotic sensitivity. Moreover, it has been shown that erythrocytes treated with acrolein significantly reduce the non-enzymatic antioxidant potential of the cytosol compared to the control.

Mechanism of CuSO4 cytotoxicity in goat erythrocytes after high-level in vitro exposure to isotonic media.

Copper (Cu) is a common environmental pollutant in nature. Cu-poisoning can cause liver damage and erythrocytes hemolysis. To evaluate the effect of CuSO4 poisoning on the morphological and functional characteristics of goat red blood cells. Five 10-14-month-old goats were selected for jugular vein blood sampling to obtain erythrocytes, and then the erythrocytes were processed with different concentrations (0, 10, 20, 30, 40 and 50 µmol/L) of CuSO4 for 48 h, and 40 µmol/L doses CuSO4 incubated for different time (12, 24, 36, 48 and 60 h) to process erythrocytes. We observed the changes in erythrocyte morphology through scanning electron microscopy, and detected the antioxidant function and activities of three ATPases. Additionally, biological properties were examined from the perspectives of phospholipids and membrane protein components, permeability fragility, and fluidity in erythrocytes. We found that after CuSO4 treatment, the antioxidant capacity of erythrocytes decreased, which was manifested as increased MDA content and decreased CuZn-SOD and GSH-Px activities (p < 0.05). In addition, we also found that erythrocyte fluidity decreased, osmotic fragility increased, membrane phospholipid percentage and protein composition changes abnormally, and Na+/K+-ATPase, Mg2+-ATPase and Ca2+-ATPase activities decreased (p < 0.05). From the results, it can be concluded that CuSO4 exposure causes hemolysis of goat erythrocytes through oxidative stress to the structure and function of erythrocytes, showing a dose-time effect.

Oxidative stress assessment in sickle cell anemia patients treated with hydroxyurea.

Hydroxyurea (HU) is used as a therapy in sickle cell anemia (SCA). Many studies have established that HU improves patient quality of life by reducing symptoms. However, the effect of HU on erythrocytes is not well-described. We evaluated several parameters related to oxidative stress and total lipid content of erythrocytes in patients with SCA. The patient cohort consisted of 7 SCA patients treated with HU, 17 untreated SCA patients, and 15 healthy subjects. Erythrocytes from patients with SCA displayed increased oxidative stress relative to the control group, including higher thiobarbituric acid reactive substances (TBARS), Fe3+ content, and osmotic fragility, and decreased total cholesterol. We observed that treatment of SCA patients with HU increased Fe3+ content and activity of glutathione peroxidase, and decreased glutathione reductase activity, glutathione levels, total cholesterol, and phospholipid content comaperaded to patients untreated with HU. Thus, HU alters biochemical characteristics of erythrocytes; future studies will determine whether they are beneficial or not.

Effects of L-carnitine on the erythrocytes of stored human blood.

OBJECTIVES: This study aimed to assess the effects of L-carnitine on oxidative stress in human erythrocytes during storage. BACKGROUND: Using antioxidants as components of blood storage solutions may combat the effects of storage-induced oxidative stress on erythrocytes. METHODS: Blood from male adults was stored at 4 °C for 55 days in citrate phosphate dextrose adenine solution, without L-carnitine (Control) and with L-carnitine as an additive (at concentrations of 10, 30 and 60 mM - Experiments). Every fifth day, erythrocyte markers (morphology, count, haemoglobin, haemolysis and osmotic fragility), antioxidant defences (antioxidant enzymes and total antioxidant capacity) and oxidative stress markers (superoxides, lipid peroxidation and protein oxidation products) were analysed. RESULTS: Oxidative damage was observed in controls (day 25 onwards) and in experiments (day 35 onwards). L-carnitine (10 and 30 mM) protected erythrocytes from damage up to day 35 by maintaining haemoglobin and lipid peroxidation, assisting antioxidant enzymes and increasing antioxidant capacity by elevating sulfhydryls and ascorbic acid. L-carnitine was beneficial in prolonging storage up to 55 days but could not prevent oxidative damage completely in terms of haemolysis and osmotic fragility. CONCLUSIONS: L-carnitine ameliorated oxidative stress, but combinations with other antioxidants may provide comprehensive protection to erythrocytes during storage.

The Predictive Value of Salt Sensitivity and Osmotic Fragility in the Development of Cerebral Small Vessel Disease.

Increased salt intake in food probably affects the progression of cerebral small vessel disease (CSVD), which justifies the study of disturbances in sodium homeostasis associated with the development of CSVD. We aimed to clarify the role of salt sensitivity and osmotic fragility in the development of CSVD. Erythrocyte salt sensitivity was measured using the modified salt blood test, and osmotic fragility was measured using the classic osmotic fragility test in 73 patients with CSVD (48 women; 60.1 ± 6.5 years) and 19 healthy volunteers (14 women; 56.9 ± 6.4 years). Salt sensitivity and osmotic fragility exhibited a predictive value in relation to CSVD. These parameters were associated with an increase in white matter hyperintensities (P = 0.019 and 0.004, respectively). Their simultaneous use increased their predictive ability for CSVD (P < 0.000001; AUC (95% CI), 0.824 (0.724-0.923)). The possibility of predicting CSVD using erythrocyte salt sensitivity and osmotic fragility indicates the value of the individual glycocalyx buffer capacity in relation to sodium and the activity of sodium channels in the development of CSVD. Increased salt sensitivity and osmotic fragility seem to be risk factors for CSVD.

Cell Swelling Induced by the Antimalarial KAE609 (Cipargamin) and Other PfATP4-Associated Antimalarials.

For an increasing number of antimalarial agents identified in high-throughput phenotypic screens, there is evidence that they target PfATP4, a putative Na+ efflux transporter on the plasma membrane of the human malaria parasite Plasmodium falciparum For several such "PfATP4-associated" compounds, it has been noted that their addition to parasitized erythrocytes results in cell swelling. Here we show that six structurally diverse PfATP4-associated compounds, including the clinical candidate KAE609 (cipargamin), induce swelling of both isolated blood-stage parasites and intact parasitized erythrocytes. The swelling of isolated parasites is dependent on the presence of Na+ in the external environment and may be attributed to the osmotic consequences of Na+ uptake. The swelling of the parasitized erythrocyte results in an increase in its osmotic fragility. Countering cell swelling by increasing the osmolarity of the extracellular medium reduces the antiplasmodial efficacy of PfATP4-associated compounds, consistent with cell swelling playing a role in the antimalarial activity of this class of compounds.

Pathophysiological aspects of red blood cells in end-stage renal disease patients resistant to recombinant human erythropoietin therapy.

OBJECTIVE: Modified, bioreactive red blood cells (RBCs) and RBC-derived microvesicles (MVs) likely contribute to the hematological and cardiovascular complications in end-stage renal disease (ESRD). This study assesses the physiological profile of RBCs in patients with ESRD receiving standard or high doses of recombinant human erythropoietin (rhEPO). METHOD: Blood samples from twenty-eight patients under sustained hemodialysis, responsive, or not to standard rhEPO administration were examined for RBC morphology, fragility, hemolysis, redox status, removal signaling, membrane protein composition, and microvesiculation before and after dialysis. Acute effects of uremic plasma on RBC features were examined in vitro through reconstitution experiments. RESULTS: Overall, the ESRD RBCs were characterized by pathological levels of shape distortions, surface removal signaling, and membrane exovesiculation, but reduced fragility compared to healthy RBCs. Irreversible transformation of RBCs was found to be a function of baseline Hb concentration. The more toxic uremic context in non-responsive patients compared to rhEPO responders was blunted in part by the antioxidant, antihemolytic, and anti-apoptotic effects of high rhEPO doses, and probably, of serum uric acid. A selective lower expression of RBC membrane in complement regulators (CD59, clusterin) and of CD47 "marker-of-self" was detected in non-responders and responders, respectively. Evidence for different short-term dialysis effects and probably for a different erythrocyte vesiculation mechanism in rhEPO responsive compared to non-responsive patients was also revealed. CONCLUSION: Deregulation of RBC homeostasis might involve diverse molecular pathways driving erythrocyte signaling and removal in rhEPO non-responders compared to responsive patients.

Chlorpyrifos and lambda cyhalothrin-induced oxidative stress in human erythrocytes.

Pesticides are one of the most potentially harmful chemicals introduced into the environment, and their adverse impacts on non-target organisms can be significant. The present study was conducted to shed light on effects of locally used insecticides chlorpyrifos (CPF) and lambda cyhalothrin (LCT) on oxidative stress biomarkers in human erythrocytes. The activity of catalase (CAT), superoxide dismutase (SOD), and protein contents as well as the levels of malondialdehyde (MDA) and osmotic fragility (OF) were measured in human erythrocytes exposed to CPF at concentrations of 0, 100, 500, 1000, and 2000 ppm and LCT at concentrations of 0, 100, 300, 600, and 800 ppm for 1 h and 3 h at 37°C. MDA levels and OF of erythrocytes were significantly higher in erythrocytes incubated with CPF and LCT at increasing concentrations of both insecticides and increased incubation time. However, erythrocyte CAT and SOD activities were decreased at all concentrations of CPF and LCT tested. Protein oxidation products were decreased at lower doses of CPF (100 and 500 ppm); at higher doses (1000 and 2000 ppm), total protein content was increased compared with control. In contrast LCT was associated with decreased in protein contents at all the concentrations. These results clearly demonstrated that CPF and LCT can induce oxidative stress in human erythrocytes ( in vitro).

Evaluation of methylglyoxal toxicity in human erythrocytes, leukocytes and platelets.

Methylglyoxal (MG) is a reactive dicarbonyl metabolite originated mainly from glucose degradation pathway that plays an important role in the pathogenesis of diabetes mellitus (DM). Reactions of MG with biological macromolecules (proteins, DNA and lipids) can induce cytotoxicity and apoptosis. Here, human erythrocytes, leukocytes and platelets were acutely exposed to MG at concentration ranging from 0.025 to 10 mM. Afterwards, hemolysis and osmotic fragility in erythrocytes, DNA damage and cell viability in leukocytes, and the activity of purinergic ecto-nucleotidases in platelets were evaluated. The levels of glycated products from leukocytes and free amino groups from erythrocytes and platelets were also measured. MG caused fragility of membrane, hemolysis and depletion of amino groups in erythrocytes. DNA damage, loss of cell viability and increased levels of glycated products were observed in leukocytes. In platelets, MG inhibited the activity of enzymes NTPDase, 5'-nucleotidase and adenosine deaminase (ADA) without affecting the levels of free amino groups. Our findings provide insights for understanding the mechanisms involved in MG acute toxicity towards distinct blood cells.

Effects of L-glutamine on rectal temperature and some markers of oxidative stress in Red Sokoto goats during the hot-dry season.

The experiment investigated the ameliorative effects of L-glutamine administration on rectal temperature (RT), erythrocyte osmotic fragility (EOF), serum antioxidant enzyme activities and malondialdehyde (MDA) concentration in Red Sokoto goats during the hot-dry season. Twenty eight healthy Red Sokoto goats, comprising 14 experimental (administered 0.2 g/kg of L-glutamine dissolved in 10 mL of distilled water, once daily for 21 days) and 14 control (administered equivalent of distilled water) goats served as subjects. Rectal temperature (measured at 6:00, 13:00 and 18:00 h) and blood samples (taken at 8:00 h) were obtained from all subjects weekly, before, during and after L-glutamine administration. Data obtained were compared using one-way repeated-measures ANOVA, followed by Tukey's post-hoc test. The dry-bulb temperature, relative humidity and temperature-humidity index for the study period ranged between 24.0 and 37.5 °C, 26.0 and 84.0% and 73.0 and 86.3, respectively. L-glutamine administration decreased (P < 0.05) RT, EOF and MDA and increased superoxide dismutase (SOD) activity in experimental group, compared to controls during weeks 1, 2 and 3. Glutathione peroxidase (GPx) and catalase activities were higher (P < 0.05) in the experimental group than in the controls only during week 1 of L-glutamine administration. In conclusion, L-glutamine administration mitigated increases in RT, EOF and serum MDA concentration and enhanced serum SOD, GPx and catalase activities and may be beneficial in heat-stressed goats during the hot-dry season.

Biophysical Properties and Motility of Human Mature Dendritic Cells Deteriorated by Vascular Endothelial Growth Factor through Cytoskeleton Remodeling.

Dendritic cells (DCs), the most potent antigen-presenting cells, play a central role in the initiation, regulation, and maintenance of the immune responses. Vascular endothelial growth factor (VEGF) is one of the important cytokines in the tumor microenvironment (TME) and can inhibit the differentiation and functional maturation of DCs. To elucidate the potential mechanisms of DC dysfunction induced by VEGF, the effects of VEGF on the biophysical characteristics and motility of human mature DCs (mDCs) were investigated. The results showed that VEGF had a negative influence on the biophysical properties, including electrophoretic mobility, osmotic fragility, viscoelasticity, and transmigration. Further cytoskeleton structure analysis by confocal microscope and gene expression profile analyses by gene microarray and real-time PCR indicated that the abnormal remodeling of F-actin cytoskeleton may be the main reason for the deterioration of biophysical properties, motility, and stimulatory capability of VEGF-treated mDCs. This is significant for understanding the biological behavior of DCs and the immune escape mechanism of tumors. Simultaneously, the therapeutic efficacies may be improved by blocking the signaling pathway of VEGF in an appropriate manner before the deployment of DC-based vaccinations against tumors.

In vitro effects of plant essential oils on non-specific immune parameters of red drum, Sciaenops ocellatus L.

Phytochemicals such as plant essential oils (EOs) have been reported to favour various activities in the innate immune system of fish. Thus, the aim of this study was to verify the in vitro effect of three different plant EOs (Ocimum americanum, Cymbopogon flexuosus and Melaleuca alternifolia) on non-specific immune parameters and erythrocyte osmotic fragility of red drum, Sciaenops ocellatus. Concentrations of each plant EO evaluated in preparations of head-kidney macrophages, blood leucocytes and blood plasma were as follows: 0.0 (control), 1.0, 2.0, 4.0, 8.0, and 16.0 µg/ml. Red drum head-kidney macrophages significantly increased extracellular superoxide anion production when exposed (20 h) to O. americanum EO (1.0-8.0 µg/ml) and C. flexuosus EO (2.0 and 4.0 µg/ml). The respiratory burst of blood leucocytes (NBT test) significantly increased in all concentrations when compared to the respective control group, for all EOs. At the highest concentration (16.0 µg/ml), C. flexuosus EO significantly inhibited the haemolytic activity of complement system in red drum blood after 1 h exposure. None of the tested concentrations significantly altered plasma lysozyme activity or erythrocyte osmotic fragility after exposing (1 h) red drum whole blood to each EO. This study demonstrated that these plant EOs are capable of triggering superoxide anion production in red drum leucocytes (head-kidney macrophages and/or blood leucocytes). In vivo studies are warranted to address their potential as immunostimulants in the diet of red drum and other aquacultured species.

Protective effects of pomegranate peel against hematotoxicity, chromosomal aberrations, and genotoxicity induced by barium chloride in adult rats.

CONTEXT: Pomegranate peel (PP) has health benefits including antibacterial, antioxidant, anti-inflammatory, and antimutagenic properties. OBJECTIVE: This study investigated the biochemical composition and protective effects of PP against hematotoxicity and genotoxicity induced by barium chloride (BaCl2) in adult rats. MATERIALS AND METHODS: Adult Wistar rats were divided into four groups of six each: control, barium (67 ppm via drinking water), PP (5% via diet), and their combination during 21 d. Oxidative stress was determined by MDA, AOPP, and antioxidant status: CAT, GPx, GSH, Vit C. Osmotic fragility (OF), chromosomal aberrations (CAs), and micronucleus (MN) assays were also studied. RESULTS: PP showed a rich composition of antioxidant compounds. DPPH test found IC50 value= 5.3 µg/mL and a high polysaccharides content (315 ± 5 mg/g of extract). In vivo study showed a decrease in red blood cells (70%) and platelet counts (46%), hemoglobin content (8%), hematocrit percent (7%), and an 80% increase of white blood cells in Ba-treated rats. A reduction in antioxidant status: catalase, glutathione peroxidase activities, glutathione, and vitamin C levels by 31, 21, 28, and 29%, respectively, and an increase in MDA (46%) and AOPP levels (72%) were also observed compared with controls. BaCl2-treatment showed a significant increase in the frequencies of total chromosomal aberrations with abnormal metaphases and micronucleus in bone-marrow cells. Oxidative stress induced by BaCl2 might be the major cause for chromosomal abnormalities leading to DNA damage. DISCUSSION AND CONCLUSION: A decrease in hematotoxic and genotoxic effects induced by PP is due to its powerful antioxidant capacity.

AS-7 improved in vitro quality of red blood cells prepared from whole blood held overnight at room temperature.

BACKGROUND: Extended room temperature (RT) hold of whole blood (WB) may affect the quality of red blood cell (RBC) components produced from these donations. The availability of better RBC additive solutions (ASs) may help reduce the effects. A new AS, AS-7 (SOLX, Haemonetics Corporation), was investigated for improved in vitro quality of RBCs prepared from WB held overnight at RT. STUDY DESIGN AND METHODS: Sixteen WB units were held for 21.4 hours ± 40 minutes at 22°C on cooling plates before processing. Each pair of ABO-matched WB units were pooled, divided into a WB filter pack containing saline-adenine-glucose-mannitol (control) and a LEUKOSEP WB-filter pack containing SOLX, and processed according to manufacturer's instructions. RBCs were stored at 2 to 6°C and sampled weekly until expiry. Glycophorin A (GPA+) and annexin V-binding microparticles (MPs) were quantitated using flow cytometry. Osmotic fragility, intracellular pH (pHi), adenosine triphosphate (ATP), 2,3-diphosphoglycerate (2,3-DPG), and routine quality variables were measured. Adhesion of RBCs to human endothelial cells (ECs) was evaluated by flow perfusion under low shear stress (0.5 dyne/cm(2) ), similar to low blood flow in microvessels. RESULTS: ATP and 2,3-DPG levels were improved for SOLX-RBCs. SOLX-RBCs maintained higher pHi, increased resistance to hypotonic stress, and reduced numbers of GPA+ MPs. No significant difference was observed between annexin V binding to MPs or adhesion of RBCs to ECs under shear stress. CONCLUSION: SOLX-stored RBCs showed increased osmotic resistance, pHi, and reduced GPA+ MPs and together with higher ATP and 2,3-DPG levels demonstrated improved in vitro RBC quality measures during 42 days of storage.

2-Chloro-1,4-naphthoquinone derivative of quercetin as an inhibitor of aldose reductase and anti-inflammatory agent.

The ability of flavonoids to affect multiple key pathways of glucose toxicity, as well as to attenuate inflammation has been well documented. In this study, the inhibition of rat lens aldose reductase by 3,7-di-hydroxy-2-[4-(2-chloro-1,4-naphthoquinone-3-yloxy)-3-hydroxy-phenyl]-5-hydroxy-chromen-4-one (compound 1), was studied in greater detail in comparison with the parent quercetin (compound 2). The inhibition activity of 1, characterized by IC50 in low micromolar range, surpassed that of 2. Selectivity in relation to the closely related rat kidney aldehyde reductase was evaluated. At organ level in isolated rat lenses incubated in the presence of high glucose, compound 1 significantly inhibited accumulation of sorbitol in a concentration-dependent manner, which indicated that 1 was readily taken up by the eye lens cells and interfered with cytosolic aldose reductase. In addition, compound 1 provided macroscopic protection of colonic mucosa in experimental colitis in rats. At pharmacologically active concentrations, compound 1 and one of its potential metabolite 2-chloro-3-hydroxy-[1,4]-naphthoquinone (compound 3) did not affect osmotic fragility of red blood cells.

Effects of aluminum chloride on some trace elements and erythrocyte osmotic fragility in rats.

Aluminum (Al) is a nonessential, toxic element to which humans are constantly exposed as a result of an increase in industrialization and improving technology practices. The aim of the study was to investigate the effects of different durations and doses of Al exposure on serum and tissue element levels and erythrocyte osmotic fragility in rats. A total of 40 male Wistar Albino rats were divided into five groups: control, group I (3 weeks, 8 mg/kg), group II (6 weeks, 8 mg/kg), group III (3 weeks, 16 mg/kg), and group IV (6 weeks, 16 mg/kg). Al chloride (AlCl3) was injected intraperitoneally (i.p.) five times a week. At the end of the experimental period, levels of Al, iron (Fe), copper (Cu), and zinc (Zn) in serum, liver, and kidney tissues were measured using inductively coupled plasma optical emission spectrometry. Osmotic fragility was determined using a spectrophotometer. The results of the experiment indicate that Al induced a statistically significant increase in Al and Fe concentrations in liver and serum as well as in Cu in the kidney. The Fe concentration in serum and kidney tissues was significantly lower in all the groups. As a result of our study, it may be concluded that tissue Al accumulation may lead to an increase in osmotic fragility of erythrocytes and abnormal trace element levels.

Polyphenolic Composition and Evaluation of Antioxidant Activity, Osmotic Fragility and Cytotoxic Effects of Raphiodon echinus (Nees & Mart.) Schauer.

Raphiodon echinus (R. echinus) is used in Brazilian folk medicine for the treatment of inflammation, coughs, and infectious diseases. However, no information is available on the potential antioxidant, cytotoxicity and genotoxicity of this plant. In this study, the polyphenolic constituents, antioxidant capacity and potential toxic effects of aqueous and ethanolic extracts of R. echinus on human erythrocytes and leukocytes were investigated for the first time. R. echinus extracts showed the presence of Gallic, chlorogenic, caffeic and ellagic acids, rutin, quercitrin and quercetin. Aqueous and ethanolic extracts of R. echinus exhibited antioxidant activity in DPPH radical scavenging with IC50 = 111.9 µg/mL (EtOH extract) and IC50 = 227.9 µg/mL (aqueous extract). The extracts inhibited Fe(2+) (10 µM) induced thiobarbituric acid reactive substances (TBARS) formation in rat brain and liver homogenates. The extracts (30-480 µg/mL) did not induce genotoxicity, cytotoxicity or osmotic fragility in human blood cells. The findings of this present study therefore suggest that the therapeutic effect of R. echinus may be, in part, related to its antioxidant potential. Nevertheless, further in vitro and in vivo studies are required to ascertain the safety margin of its use in folk medicine.

The effect of different high-fat diets on erythrocyte osmotic fragility, growth performance and serum lipid concentrations in male, Japanese quail (Coturnix coturnix japonica).

Poultry diets are formulated with additional animal fat or vegetable oils to improve growth rate and feed conversion efficiency. High-fat diet feeding in rats and fish has been shown to result in alterations in the phospholipid composition and cholesterol content of the erythrocyte membrane, in turn affecting erythrocyte osmotic fragility. In contrast, the few studies performed using high-fat diet feeding in avian species show no changes in erythrocyte osmotic fragility. This study made use of the Japanese quail as no data exists on investigation of this species with respect to high-fat diet feeding and erythrocyte osmotic fragility. Fifty-seven male quail were randomly divided into six groups and fed either a standard diet (commercial poultry feed) or one of five high-fat diets (commercial poultry feed with 22% of either coconut oil, lard, palm oil, soya bean oil or sunflower oil on a weight/weight basis) for 12 weeks. All birds on the high-fat diets were significantly heavier (p < 0.05) after the 12-week feeding period, than when commencing the dietary intervention. Serum triglyceride concentrations of birds in all high-fat diet groups were significantly lower (p < 0.05) than birds in the standard diet group, whereas only birds in the palm oil group had significantly lower (p < 0.05) serum cholesterol concentrations compared to the standard diet group. Fragiligrams of erythrocytes from birds in the various dietary groups were similar. High-fat diet feeding with different types of additional fat did not affect the osmotic fragility of the quail erythrocytes. Feeding quail high-energy diets of varying degrees of fatty acid saturation was well tolerated and did not seem to affect the overall health status of the birds. Resistance of avian erythrocytes to modification by excess dietary fat may be a general characteristic of avian erythrocytes.