Osmotic Fragility Research Articles

Prevalence and screening of hemoglobinopathies and glucose-6-phosphate dehydrogenase deficiency in Yemeni blood donors

ABSTRACT Hemoglobinopathies and Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency pose significant health threats in Yemen, which can be alleviated through robust preventive strategies, highlighting the importance of implementing a cost-effective and efficient blood donor screening method to facilitate early diagnosis and management of erythrocyte disorders, ultimately improving both donor safety and patient health outcomes. Objectives This study aimed to determine the prevalence of total blood cell abnormalities, hemoglobinopathies and G6PD deficiency and evaluate the efficacy of red blood cell (RBC) indices, mentzer index (MI) and naked-eye single tube red cell osmotic fragility (NESTROF) test as screening tools for diagnosis of β thalassemia trait among Yemeni blood donors. Methods A cross-sectional study was conducted with 106 volunteer blood donors who met the national standard criterion of blood donation. Various tests were performed, including complete blood count (CBC), serum ferritin, sickling test, G6PD assay, NESTROF test and high-performance liquid chromatography (HPLC). Results The prevalence of hematological abnormalities among blood donors reached 68.9%, with functional RBC abnormalities at 51.9%, leukopenia at 10.4%, thrombocytosis at 1.9%, and thrombocytopenia at 4.7%. Additionally, hemoglobinopathies were found in 21.7% of donors, with β-thalassemia trait at 3.8%, sickle cell trait at 1.9%, and suspected α-thalassemia trait at 16%, while G6PD deficiency and iron deficiency were present in 12.3% and 17.9% of donors, respectively. The NESTROF test, MCV and MCH demonstrated a sensitivity rate of 100%. MI and MCH exhibited the highest specificity followed by NESTROF test in the screening of β-thalassemia trait. Conclusions The prevalence of hemoglobinopathies and G6PD deficiency appear to be common among Yemeni blood donors. These results emphasize the necessity of comprehensive blood donation screening programs to safeguard the blood supply and promote early detection and management of hemoglobinopathies and G6PD deficiency in Yemen.

Anticonvulsant, Anticholinesterase and Cytoprotective Effects of the Aqueous Extract of Lippia sidoides Cham

(1) Background: Lippia sidoides Cham is a Brazilian aromatic plant rich in phenolic compounds. In traditional medicine, its leaves are used to treat diseases of the Central Nervous System such as stress and anxiety. This study evaluates the capacity of the aqueous extract of L. sidoides as an anticonvulsant, anticholinesterase and antihemolytic agent. (2) Methods: The extract was obtained from the leaves using water as a solvent, then dried in a spray dryer. The anticonvulsant effect was evaluated in zebrafish models using the pentylenetetrazol (PTZ) method. The anticholinesterase effect was determined using the acetylcholinesterase enzyme and physostigmine as a positive control. The antihemolytic action was evaluated by exposing erythrocytes to different concentrations of NaCl in the presence and absence of the extract. (3) Results: The anticonvulsant effect was observed at a concentration of 400 mg/kg, delaying convulsive crises. In the anticholinesterase assay, a dose-dependent action and variation in the effect over time were observed, demonstrating a reversible effect of the extract. For the osmotic fragility test, the extract showed satisfactory results, providing cellular protection across all variations of NaCl concentration. (4) Conclusions: These results demonstrate the promising potential of L. sidoides extract for the development of drugs that act in the treatment of diseases that affect the Central Nervous System.

Altered RBC deformability in diabetes: clinical characteristics and RBC pathophysiology

BackgroundReduced red blood cell deformability (RBCD) is associated with diabetic vascular complications, but early pathophysiological RBC changes and predictive demographic and clinical factors in populations with diabetes are unclear. An understanding of early diabetes-specific RBC changes associated with impaired RBCD is essential in investigating mechanisms that predispose to diabetic vascular complications.MethodsWe conducted an outpatient cross-sectional study of participants in a well-controlled diabetes cohort (N81) and nondiabetic controls (N78) at the National Institutes of Health. First, between-group differences in RBCD measures were assessed with shear stress-gradient ektacytometry. Differences in structural RBC parameters were assessed using osmotic gradient ektacytometry and NaCl osmotic fragility. Functional RBC changes were assessed using hemoglobin-oxygen dissociation: p50.ResultsAll shear-stress gradient RBCD measures were significantly altered in the diabetes cohort vs. nondiabetic controls, even after adjustment for confounding covariates (p < 0.001). Adjusted for diabetes-status and demographic factors, significant predictors of reduced RBCD included older age, Black race, male gender, hyperglycemia, and vascular complications (all p < 0.05). Reduced RBCD was also associated with aberrant osmotic-gradient parameters, with a left-shift on osmotic gradient profile indicative of dehydrated RBCs in diabetes. A structure-function relationship was observed with reduced RBCD associated with reduced osmotic fragility (P < 0.001) and increased hemoglobin-oxygen dissociation (P < 0.01).ConclusionsFindings suggest impaired RBCD incurs similar demographic and clinical risk factors as diabetic vascular disease, with early pathophysiological RBC changes indicative of disordered RBC hydration in diabetes. Findings provide strong evidence for disordered oxygen release as a functional consequence of reduced RBCD.Clinical trial number: NCT00071526.

Physiological adaptations of red blood cells during aestivation in the south American lungfish Lepidosiren paradoxa

The South American lungfish Lepidosiren paradoxa inhabits areas with variable pluvial regimes. During aestivation (dormancy state observed in some species during dry seasons), the prolonged period of dryness imposes osmotic stress. We aimed to investigate the physiological and morphological adaptations of RBCs in Lepidosiren paradoxa during aestivation. Here, the lungfish were subjected to aestivation for 20 and 40 days and compared to a control group in an active period. The osmotic fragility, blood osmolality, and pH were measured. Blood smears were performed to assess morphological changes in the RBCs. Lepidosiren paradoxa presented lower hemolysis when compared with a teleost fish and tegu lizard. Hemolysis increased when the lungfish was subjected to 40 days of aestivation (from 6.04 % to 16.51 %; control vs 40-day aestivation). Hematocrit rose in both aestivation groups compared to the control (26.36 %, 41.36 % and 41 %, control, 20 and 40 days, respectively; p < 0.05) indicating changes in RBC volume and hydration status. Moreover, the results revealed increased osmolality in the 40-day aestivation group (244.4 vs 372.1 mmol/Kg; control vs 40-day aestivation). 40 days of aestivation led to a decrease in blood pH when compared to the control and 20-day aestivation groups. Both aestivation durations resulted in a reduction in the perimeter and cell diameters in at least one direction of the RBCs (24 % mean reduction in size from control to 40 days aestivation). These findings suggest that South American lungfish possess remarkable physiological and morphological adaptations in their RBCs during aestivation.

Asiatic acid impedes NSCLC progression by inhibiting COX-2 and modulating PI3K signaling.

Non-small cell lung cancer comprises up to 85% of lung cancer cases and has a poor prognosis. At present, there are still no effective treatments for this illness. Evidence suggests that the prostaglandin [cyclooxygenase-2 (COX-2)] and leukotriene [lipoxygenase-5 (5-LOX)] pathways are involved in lung cancer carcinogenesis. Therefore, novel agents that target COX-2 and 5-LOX may have therapeutic potential. In the present study, we examined the role of asiatic acid (AA), a triterpenoid saponin, in targeting the protein kinases responsible for lung cancer proliferation and mobility. The experimental data revealed that AA inhibited the growth of lung cancer cells (> 50%) and it significantly impeded the proliferation of lung cancer cells by inhibiting COX-2, which results in downregulation of the phosphotidyl inositol-3 kinase/protein kinase B/mammalian target of rapamycin signaling pathway, leading to an induction of cytotoxic autophagy-mediated apoptosis. Mechanistically, the expression of mitogen-activated protein kinase/extracellular signal-regulated kinase, hypoxia-inducible factor-1 and vascular endothelial growth factor is downregulated by AA, thereby reducing cell mobility and invasion. It also shows negative osmotic fragility on healthy human erythrocytes. It is concluded that AA may be a viable therapeutic drug for non-small cell lung cancer treatment, which opens new opportunities for synthesizing analogues.

Excessive Erythrophagocytosis Accounts for Systemic Inflammation in Chronic Kidney Disease.

Chronic kidney disease (CKD) is associated with persistent systemic inflammation. Reduced red blood cell (RBC) survival in patients with CKD has been identified for several decades. The purpose of this study is to explore whether excessive erythrophagocytosis exists and contributes to systemic inflammation in CKD. A CKD rat model was induced by 5/6 nephrectomy. Erythrocyte osmotic fragility was determined with hypotonic NaCl solutions. Erythrocyte deformability was evaluated by filterability. RBC cell death was quantified using fluorescence-activated cell sorting analyses of fluorescent annexin V-bound surface phosphatidylserine (PS). Erythrophagocytosis was evaluated in vivo and in vitro. RT-qPCR and immunohistochemistry were used to determine the inflammatory effects after erythrophagocytosis. Erythrocyte osmotic fragility and deformability progressively declined, and the percentage of PS-exposing RBCs progressively increased in CKD rats. Levels of erythrophagocytosis in vivo were evaluated by autologous injection of CFSE-labeled erythrocytes. In comparison with the control group, higher fluorescence intensity of CFSE was detected in the spleen homogenates of rats with CKD. In vitro, more of erythrocytes from 5/6Nx rats were phagocytosed by peritoneal macrophages in comparison to those from control rats. Compared with macrophages phagocytosed control erythrocytes, macrophages phagocytosed CKD erythrocytes exhibited higher mRNA levels of IL-6, CXCL-10, CXCL-11, iNOS, IL-1β, ICAM-1 and MCP-1. Compared with the control group, the red pulp of rats with CKD exhibited higher levels of p-NFκB, IL-6, iNOS and CXCL-10. ELISA results showed significantly increased plasma levels of both IL-6 and CXCL-10 in patients with long-term hemodialysis compared with those in healthy controls (2.30 ± 1.38 pg/mL vs 1.33 ± 0.65 pg/mL, P=0.01; 78.11 ± 27.34 pg/mL vs 37.45 ± 7.08 pg/mL, P=0.001). Our results indicated that excessive erythrophagocytosis may contribute to systemic inflammation in CKD.

LC-MS/MS Analysis of crude Flavonoid Compounds from &lt;i&gt;Justicia secunda&lt;/i&gt; from Democratic Republic of the Congo and evaluation of their antisickling Activity

&lt;i&gt;Justicia secunda&lt;/i&gt; Vahl (Acanthaceae) is a tropical herbaceous plant traditionally used by indigenous peoples of the Democratic Republic of the Congo (DRC) to treat symptoms associated with sickle cell disease (SCD), a genetic condition with life-threatening complications. Given the lack of side-effect-free drugs, alternative herbal therapies that can reduce or reverse red blood cell sickling may serve as safe and effective treatments. The primary objective of this study is to conduct a phytochemical screening of crude flavonoids extracted from &lt;i&gt;J. secunda&lt;/i&gt; using LC-ESI/MS/MS. &lt;i&gt;J. secunda&lt;/i&gt; extracts were evaluated for their phytoconstituents and anti-sickling properties. The anti-sickling properties were assessed through reverse sickling estimation, polymerization and oxidation inhibition, and osmotic fragility assays. Fractionation of the methanol extract and chemical profiling were performed by flash chromatography and high-performance thin-layer chromatography analysis respectively. Characterization and identification of the crude flavonoids were done using chromatography and spectroscopy methods. Chemical screening of crude flavonoids revealed the presence of 12 flavonoid O-glycosides based on one flavonol (methoxy-kaempferol) and two flavones (luteolin and apigenin). The crude flavonoid extracts demonstrated maximum reversal of sickled red blood cells (91.9 ± 0.8%), significant inhibition of hemoglobin polymerization (77.8 ± 7.6%) and hemoglobin S auto-oxidation (96.3 ± 0.2), and provided maximum protection of red blood cells against hyperhemolysis. The results validate the traditional use of &lt;i&gt;J. secunda&lt;/i&gt; and identify potential compounds for the development of novel anti-sickling agents.

Anti-anemic potential of Eruca sativa L. in iron-deficient rat model; network pharmacology profiling.

Iron deficiency anemia is a global health concern, affecting around 2 billion people. Oral iron therapy often causes severe gastro-intestinal issues. Eruca sativa, member of the Brassicaceae family, is valued in traditional medicine and renowned for its rich iron and vitamin C content. This study aims to evaluate the anti-anemic properties of E. sativa extract invivo and identify its compounds targeting anemia mechanisms using network pharmacology. Thirty-two Sprague-Dawley rats (200 ± 250 g) were split into two distinct groups, iron-deficient and iron-sufficient. Three different doses (200, 400, and 800 mg/kg) of aqueous extract of E. sativa were checked against anemia by studying hematological, oxidative stress, and histopathological parameters. GC-MS analysis of E. sativa revealed its phytochemical profile, followed by ADME screening. Network pharmacology explored targets related to iron deficiency anemia, with oral bioavailability and drug likeness assessment for compounds. The administration of extracts significantly improved various blood parameters, including osmotic fragility, Hb, RBCs, MCV, PCV, and alkaline phosphatase; catalase activity; and histopathological parameters such as liver in both iron-deficient and iron-sufficient rats (p < .001). Seventy-nine compounds were identified in E. sativa aqueous extract, with only six of them found to be bioavailable and drug-like against multiple targets. Gene ontology and pathway analysis revealed their diverse molecular, biological, and cellular functions. One gene EGFR was found to have functional association with ID anemia, suggesting potential for using E. sativa extracts. The study concludes that E. sativa extract has potential for iron deficiency anemia treatment, offering hope for future pharmaceutical interventions.

Ultraviolet light and riboflavin accelerates red blood cell dysfunction in vitro and in a guinea pig transfusion model.

Quality assessment of modified or processed red blood cell (RBC) components, such as pathogen-reduced RBCs, using only in vitro testing may not always be predictive of in vivo performance. Mouse or rat in vivo models are limited by a lack of applicability to certain aspects of human RBC biology. Here, we used a guinea pig model to study the effects of riboflavin combined with UV light on the integrity of RBCs in vitro and following transfusion in vivo. Guinea pig RBCs were collected from whole blood (WB) treated with varying UV doses (10, 20, 40 or 80 J/mL) in the presence of riboflavin (UVR-RBCs). In vitro tests for UVR-RBCs included hemolysis, osmotic fragility, and cellular morphology by scanning electron microscopy. Guinea pigs transfused with one-day post-treatment UVR-RBCs were evaluated for plasma hemoglobin (Hb), non-transferrin bound iron (NTBI), total iron and Perls-detectable hemosiderin deposition in the spleen and kidney, and renal uptake of Hb. Acute RBC injury was dose dependently accelerated after treatment with UV light in the presence of riboflavin. Aberrant RBC morphology was evident at 20, 40, and 80 J/mL, and membrane lysis with Hb release was prominent at 80 J/mL. Guinea pigs transfused with 40 and 80 J/mL UVR-RBCs showed increased plasma Hb levels, and plasma NTBI was elevated in all UVR-RBC groups (10-80 J/mL). Total iron levels and Perls-hemosiderin staining in spleen and kidney as well as Hb uptake in renal proximal tubules were increased 8 hours post-transfusion with 40 and 80 J/mL UVR-RBCs. UVR-RBCs administered to guinea pigs increased markers of intravascular and extravascular hemolysis in a UV dose-dependent manner. This model may allow for the discrimination of RBC injury during testing of extensively processed RBCs intended for transfusion.

A Comparative Analysis of Erythrocyte Osmotic Fragility across Vertebrate Taxa

A Comparative Analysis of Erythrocyte Osmotic Fragility across Vertebrate Taxa

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.

Mild Systemic Inflammation Increases Erythrocyte Fragility.

There is growing evidence that inflammation impairs erythrocyte structure and function. We assessed the impact of mild systemic inflammation on erythrocyte fragility in three different settings. In order to investigate causation, erythrocyte osmotic fragility was measured in mice challenged with a live attenuated bacterial strain to induce low-grade systemic inflammation; a significant increase in erythrocyte osmotic fragility was observed. To gather evidence that systemic inflammation is associated with erythrocyte fragility in humans, two observational studies were conducted. First, using a retrospective study design, the relationship between reticulocyte-based surrogate markers of haemolysis and high-sensitivity C-reactive protein was investigated in 9292 healthy participants of the UK Biobank project. Secondly, we prospectively assessed the relationship between systemic inflammation (measured by the urinary neopterin/creatinine ratio) and erythrocyte osmotic fragility in a mixed population (n = 54) of healthy volunteers and individuals with long-term medical conditions. Both human studies were in keeping with a relationship between inflammation and erythrocyte fragility. Taken together, we conclude that mild systemic inflammation increases erythrocyte fragility and may contribute to haemolysis. Further research is needed to assess the molecular underpinnings of this pathway and the clinical implications in inflammatory conditions.

Complete absence of GLUT1 does not impair human terminal erythroid differentiation

AbstractThe glucose transporter 1 (GLUT1) is 1 of the most abundant proteins within the erythrocyte membrane and is required for glucose and dehydroascorbic acid (vitamin C precursor) transport. It is widely recognized as a key protein for red cell structure, function, and metabolism. Previous reports highlighted the importance of GLUT1 activity within these uniquely glycolysis-dependent cells, in particular for increasing antioxidant capacity needed to avoid irreversible damage from oxidative stress in humans. However, studies of glucose transporter roles in erythroid cells are complicated by species-specific differences between humans and mice. Here, using CRISPR–mediated gene editing of immortalized erythroblasts and adult CD34+ hematopoietic progenitor cells, we generate committed human erythroid cells completely deficient in expression of GLUT1. We show that absence of GLUT1 does not impede human erythroblast proliferation, differentiation, or enucleation. This work demonstrates, to our knowledge, for the first time, generation of enucleated human reticulocytes lacking GLUT1. The GLUT1–deficient reticulocytes possess no tangible alterations to membrane composition or deformability in reticulocytes. Metabolomic analyses of GLUT1–deficient reticulocytes reveal hallmarks of reduced glucose import, downregulated metabolic processes and upregulated AMP-activated protein kinase signaling, alongside alterations in antioxidant metabolism, resulting in increased osmotic fragility and metabolic shifts indicative of higher oxidant stress. Despite detectable metabolic changes in GLUT1–deficient reticulocytes, the absence of developmental phenotype, detectable proteomic compensation, or impaired deformability comprehensively alters our understanding of the role of GLUT1 in red blood cell structure, function, and metabolism. It also provides cell biological evidence supporting clinical consensus that reduced GLUT1 expression does not cause anemia in GLUT1–deficiency syndrome.

Exposure to Waterpipe Smoke Disrupts Erythrocyte Homeostasis of BALB/c Mice

The prevalence of waterpipe tobacco smoking (WPS) is increasing worldwide and is relatively high among youth and young adults. It has been shown, both experimentally and clinically, that WPS exposure adversely affects the cardiovascular and hematological systems through the generation of oxidative stress and inflammation. Our study aimed to evaluate the impact of WPS exposure on erythrocytes, a major component of the hematological system, of BALB/c mice. Here, we assessed the effect of nose-only WPS exposure for four consecutive weeks on erythrocyte inflammation, oxidative stress, and eryptosis. The duration of the session was 30 min/day, 5 days/week. Control mice were exposed to air. Our results showed that the levels of C-reactive protein, lipid peroxidation (LPO), superoxide dismutase, and total nitric oxide (NO) were significantly increased in the plasma of WPS-exposed mice. The number of erythrocytes and the hematocrit were significantly decreased in WPS-exposed mice compared with the control group. Moreover, there was an increase in the erythrocyte fragility in mice exposed to WPS compared with those exposed to air. The levels of lactate dehydrogenase, LPO, reduced glutathione, catalase, and NO were significantly increased in the red blood cells (RBCs) of WPS-exposed mice. In addition, erythrocytes of the WPS-exposed group showed a significant increase in ATPase activity, Ca2+, annexin V binding, and calpain activity. Taken together, our findings suggest that WPS exposure elevated inflammation and oxidative stress in the plasma and induced hemolysis in vivo. It also caused alterations of RBCs oxidative stress and eryptosis in vitro. Our data confirm the detrimental impact of WPS on erythrocyte physiology.

Unveiling the Antianemic Activity, Physicochemical Aspects, Antioxidant Properties, and Mineral Profile of Petroselinum crispum L.

Anemia is a widespread global health concern necessitating effective, accessible, and natural interventions. The potential of medicinal plants to address anemia has garnered significant interest. Among these plants, parsley (Petroselinum crispum (Petroselinum crispum) L.) stands out as an edible and herbal-based option for combating anemia. Aim of the study: This study investigated the potential of P. crispum (PC-Ext) as an emerging antianemic product, focusing on its physicochemical attributes, antioxidant properties, and mineral profile. Both qualitative and quantitative analyses of the phenolic compounds in P. crispum were conducted by using high-performance liquid chromatography with a diode array detector (HPLC-DAD). Anemia was induced in rats by intravenous injections of phenylhydrazine, administered at a dose of 40 mg/kg for two consecutive days. The antianemic activity of PC-Ext was assessed at a dose of 500 mg/kg twice daily for 5 weeks by estimating blood parameters, such as serum iron and ferritin. Additionally, the osmotic fragility test measured the capacity of red blood cells to withstand osmotic shock of various concentrations of saline. Aqueous extract of P. crispum was rich in phytochemical compounds, including syringic acid, quercetin, catechin, gallic acid, and luteolin. The findings demonstrate the effectiveness of P. crispum in ameliorating phenylhydrazine-induced reductions in red blood cell count (RBCs), hemoglobin (Hb), and hematocrit (HCT) levels. Consequently, PC-Ext exhibits significant activity against phenylhydrazine-induced anemia in rats, as demonstrated by its ability to prevent hemolysis. Iron estimation within PC-Ext further confirms its utility in addressing both iron deficiency and ferritin-deficiency anemia. Therefore, PC exhibits a favorable effect against both types of anemia, iron deficiency, and hemolysis. The results of this study provide robust scientific validation for ethnomedicinal use and the potential utility of P. crispum, positioning it as a promising source for future pharmaceutical development.

Assessing NESTROFT as a preliminary screening tool for thalassemia in the Malayali tribes of Dharmapuri district, Tamil Nadu, India.

Mutations affecting transcription, translation, or beta-globin stability, among other stages of beta-globin production, cause beta-thalassemia. Beta-thalassemia results in a high red blood cell count with a low mean corpuscular volume (60-70fl) and mean corpuscular hemoglobin (19-23pg), and Naked Eye Single Tube Red Cell Osmotic Fragility Test (NESTROFT) is recommended for mass screening of populations. Among tribals in Dharmapuri district, this cross-sectional analysis evaluated the efficacy of RBC and NESTROFT against HPLC, regarded as the gold standard, in a study involving 484 subjects. Findings indicated that out of the 484 samples, 73 tested positive for the beta-thalassemia trait through HPLC. The NESTROFT test demonstrated 87% sensitivity, 98.5% specificity, a positive predictive value of 99.3%, and a negative predictive value of 73.3%. In the multivariate analysis, NESTROFT and hemoglobin showed high significance with P values of 0.003 and 0.000, respectively. NESTROFT's high sensitivity is particularly noteworthy due to the absence of research among the Malayali tribes in the Dharmapuri district. Adoption of this preliminary test shows promise in detecting the disease at the local level, providing important information for early detection, especially considering the sizeable tribal population.

FATAL ACUTE HEMOLYSIS FOLLOWING TRIAZOLE THERAPY IN AFRICAN PENGUINS (SPHENISCUS DEMERSUS).

Aspergillosis is a major cause of morbidity and mortality in penguins, with triazole antifungal drugs being commonly used for prophylaxis and treatment. This report describes 15 cases of fatal hemolysis associated with liquid itraconazole and voriconazole formulations administered to African penguins (Spheniscus demersus) from four institutions. All penguins underwent stressful events (e.g. relocation, induced molt) and were administered commercial liquid itraconazole formulations or compounded voriconazole liquid suspension. Observed clinical signs in affected penguins prior to death included hyporexia, weight loss, lethargy, dyspnea, red-tinged droppings, and obtunded mentation. Intra- and extravascular hemolysis and hemoglobinuric nephrosis were the primary pathologic manifestations on postmortem examination. The concentration-dependent hemolytic potentials of itraconazole, voriconazole, and commercial and compounded vehicle suspensions were evaluated in vitro by exposing chicken whole blood as a surrogate for penguin blood. Hemoglobin content in blood plasma was then measured by spectrophotometry. Neither itraconazole nor voriconazole alone induced hemolysis in vitro. The vehicle ingredients sorbitol and hydromellose induced hemolysis, but not at predicted plasma levels in chicken erythrocytes, suggesting neither the azole antifungals nor their major vehicles alone were likely to contribute to hemolysis in vivo in these penguins. Potential mechanisms of toxicosis include generation of an unmeasured reactive metabolite causing hemolysis, preexisting erythrocyte fragility, or species-specific differences in hemolytic thresholds that were not assessed in the chicken erythrocyte model. More research is needed on the potential for toxicosis of azole antifungal drugs and carrier molecules in this and other avian species.

Anti-sickling effect of Vigna subterranean (L.) Verdc on sickle cell beta thalassemia

Sickle cell disease affects millions of people worldwide and has been recognized as a global health concern by WHO. Presently, there is no cure for sickle cell disease. Treatment options which include bone marrow, stem cell transplantation, blood transfusions, and hydroxyurea are not only expensive but have their side effects. Medicinal plants are often employed in the treatment of diseases because of the therapeutic effects of the secondary metabolites in them. Vigna subterranean an important leguminous crop in Africa, is used in some parts of the world for the treatment and management of sickle cell disease. However, there are no established link between the use of Vigna subterranean and their pharmacological effects. The present study investigated the therapeutic effect of Vigna subterranean on a variant of sickle cell disease known as sickle cell beta thalassemia. Parameters such as reversibility test, polymerization test, osmotic fragility test, deoxygenation test, beta synthesis and oxy-haemoglobin concentration were used to study the anti-sickling potentials of sickle cell beta thalassemia. The result showed that the plant extract reversed the sickled cells, reduced the rate of polymerization, maintained the stability of the cell membrane, increased beta globin synthesis and increased the oxy-haemoglobin concentration. This suggests that Vigna subterranean possesses anti-sicking properties and could be used as an effective therapeutic for the treatment and management of sickle cell beta thalassemia.

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.

Modification of deglycerolization procedure improves processing and post-thaw quality of cryopreserved sickle trait red cell concentrates

Red blood cell (RBC) transfusion is a critical therapy for those with sickle cell disease (SCD). Alloimmunization is frequent for those with SCD and may limit the availability of matched RBC. Cryopreserved RBCs, from family members or donors with a similar RBC antigen profile could provide a viable alternative to avoid further alloimmunization and prevent hemolytic transfusion-related events. However, cryopreserved SCD and Sickle Cell trait (S-trait) donor RBC units suffer from reduced recovery following deglycerolization. This study proposes and tests a modified deglycerolization protocol using an automated cell processor to mitigate RBC loss. Six red cell concentrates (RCC) from donors with S-trait and six control RCCs were glycerolized, frozen (<−65 °C) and deglycerolized on the ACP 215 using modified parameters (decreased hypertonic solution flow rate (100 mL/min) and hypertonic equilibration delay (120 s), and increased NaCl dilution volumes (500 mL). Quality testing included: hematocrit (HCT), hemolysis, indices, extracellular potassium, morphology, osmotic fragility, osmotic gradient ektacytometry, hemoglobin (HGB), and recovery. Canadian standards (CS) indicate that acceptable deglycerolized units for transfusion require a HCT ≤0.80 L/L, HGB ≥35 g/unit, and hemolysis <0.8 % in 90 % of units tested. No significant differences in HGB or RBC recovery were observed between study groups. Significant differences between study groups were identified in osmotic fragility and osmotic gradient ektacytometry parameters. Of the 6 S-trait RCCs, 3/6 units were within the HCT, HGB and hemolysis thresholds set by the CS. The modified deglycerolization protocol provides a path for the routine cryopreservation of S-trait RBCs.