Hereditary spherocytosis in a young female in Eastern Nepal: a case report

Introduction and importance

Hereditary spherocytosis (HS), a rare familial extravascular haemolytic disorder, typically follows an autosomal dominant inheritance pattern with variable expressivity. Despite its classical presentation of anaemia, jaundice, and splenomegaly, HS is infrequently reported among individuals of Asian descent, contributing to its under diagnosis or delayed diagnosis. The primary objective of this case report is to underscore the pivotal role of the osmotic fragility test in diagnosing HS, emphasizing the importance of accurate and timely identification for effective clinical management and improved patient outcomes.

Case presentation

The patient, without known prior co-morbidities, presented with recurrent abdominal distension, early satiety, and easy fatigability persisting for 6 years. Physical examination revealed icterus, gnathopathy, left hypochondrium tenderness, and palpable splenomegaly. The osmotic fragility of red cells was significantly elevated. The patient underwent optimization before splenectomy, receiving immunization against encapsulated bacteria. Packed red blood cell transfusions were administered to achieve optimal haemoglobin levels. Follow-up showed symptom relief, significantly improving the patient's quality of life.

Clinical discussion

This case underscores the challenges of delayed HS diagnosis, with the patient enduring symptoms for years before seeking appropriate medical attention. Overlooking the simplicity and cost-effectiveness of an osmotic fragility test prolonged the diagnostic journey, emphasizing the impact on overall well-being.

Conclusion

HS remains underdiagnosed, especially in our regions. The osmotic fragility test emerges as an economical diagnostic tool in resource-limited settings, particularly when spherocytosis is absent in the peripheral blood smears. Its inclusion in diagnostic protocols can expedite accurate HS identification and enhance patient outcomes.

Relationship between red blood cell lifespan and endogenous carbon monoxide in the common bottlenose dolphin and beluga

Certain deep-diving marine mammals [i.e., northern elephant seal (Mirounga angustirostris), Weddell seal (Leptonychotes weddellii)] have blood carbon monoxide (CO) levels that are comparable with those of chronic cigarette smokers. Most CO produced in humans is a byproduct of heme degradation, which is released when red blood cells (RBCs) are destroyed. Elevated CO can occur in humans when RBC lifespan decreases. The contribution of RBC turnover to CO concentrations in marine mammals is unknown. Here, we report the first RBC lifespans in two healthy marine mammal species with different diving capacities and heme stores, the shallow-diving bottlenose dolphin (Tursiops truncatus) and deep-diving beluga whale (Delphinapterus leucas), and we relate the lifespans to the levels of CO in blood and breath. The belugas, with high blood heme stores, had the longest mean RBC lifespan compared with humans and bottlenose dolphins. Both cetacean species were found to have three times higher blood CO content compared with humans. The estimated CO production rate from heme degradation indicates some marine mammals may have additional mechanisms for CO production, or delay CO removal from the body, potentially from long-duration breath-holds.NEW & NOTEWORTHY This is the first study to determine the red blood cell lifespan in a marine mammal species. High concentrations of carbon monoxide (CO) were found in the blood of bottlenose dolphins and in the blood and breath of belugas compared with healthy humans. Red blood cell turnover accounted for these high levels in bottlenose dolphins, but there may be alternative mechanisms of endogenous CO production that are contributing to the CO concentrations observed in belugas.

Assessment of Erythrocyte Osmotic Fragility and Its Determinants, and Comparison of Hematological Indices Among Type 2 Diabetes Mellitus Patients on Follow-Up at Jimma Medical Center, Southwest Ethiopia

Background

Diabetes Mellitus (DM) is one of the most prevalent non-communicable diseases worldwide. Approximately 9.3% of the general population was estimated to have DM globally in 2019. Erythrocyte osmotic fragility (EOF) in hyperglycemic patients is expected to increase and determine the rate of erythrocyte hemolysis.

Purpose

This study aimed to assess erythrocyte osmotic fragility (EOF) and its determinants and to compare hematological indices among T2DM patients on follow-up at the Jimma Medical Center (JMC), Jimma, Southwest Ethiopia.

Methods

A facility-based cross-sectional study involving 124 participants (each 62) of T2DM patients and controls was conducted from October to November 2020 using a structured questionnaire. 5 mL of venous blood was drawn to assess OF, complete blood count, and blood glucose levels. EOF was investigated using a series hypotonic solution of NaCl. The supernatant of the centrifuged sample was transferred to cuvette test tubes, and the hemolysis stage was read on a spectrophotometer. The collected data were coded and entered into Epi-data Version 3.1. The analysis was performed using SPSS Version 23.

Results

Compared with non-diabetic controls, patients with T2DM had significantly increased EOF. FBG >126mg/dl (AOR=7.741, 95% CI: 1.562-38.360), PPBG >200 mg/dl (AOR=7.576, 95% CI: 1.519-37.791), RDW (AOR=4.558, 95% CI: 1.136-18.284) were significantly associated with abnormal EOF. A statistically significant increase in total white blood cells and absolute neutrophil counts (P < 0.001) were observed in T2DM patients. From RBC indices, red blood cell distribution width (RDW) and mean corpuscular volume (MCV) were significantly increased in T2DM patients (P < 0.001).

Conclusion

This study suggests that EOF was greater in patients with T2DM than in non-diabetic controls and was determined by FBG, PPBG, and RDW. The study also demonstrated that hematological index alterations were higher in T2DM subjects than in non-diabetic controls.

COVID-19 impairs oxygen delivery by altering red blood cell hematological, hemorheological, and oxygen transport properties

Introduction: Coronavirus disease 2019 (COVID-19) is characterized by impaired oxygen (O2) homeostasis, including O2 sensing, uptake, transport/delivery, and consumption. Red blood cells (RBCs) are central to maintaining O2 homeostasis and undergo direct exposure to coronavirus in vivo. We thus hypothesized that COVID-19 alters RBC properties relevant to O2 homeostasis, including the hematological profile, Hb O2 transport characteristics, rheology, and the hypoxic vasodilatory (HVD) reflex. Methods: RBCs from 18 hospitalized COVID-19 subjects and 20 healthy controls were analyzed as follows: (i) clinical hematological parameters (complete blood count; hematology analyzer); (ii) O2 dissociation curves (p50, Hill number, and Bohr plot; Hemox-Analyzer); (iii) rheological properties (osmotic fragility, deformability, and aggregation; laser-assisted optical rotational cell analyzer (LORRCA) ektacytometry); and (iv) vasoactivity (the RBC HVD; vascular ring bioassay). Results: Compared to age- and gender-matched healthy controls, COVID-19 subjects demonstrated 1) significant hematological differences (increased WBC count-with a higher percentage of neutrophils); RBC distribution width (RDW); and reduced hematocrit (HCT), Hb concentration, mean corpuscular volume (MCV), and mean corpuscular hemoglobin concentration (MCHC); 2) impaired O2-carrying capacity and O2 capacitance (resulting from anemia) without difference in p50 or Hb-O2 cooperativity; 3) compromised regulation of RBC volume (altered osmotic fragility); 4) reduced RBC deformability; 5) accelerated RBC aggregation kinetics; and (6) no change in the RBC HVD reflex. Discussion: When considered collectively, homeostatic compensation for these RBC impairments requires that the cardiac output in the COVID cohort would need to increase by ∼135% to maintain O2 delivery similar to that in the control cohort. Additionally, the COVID-19 disease RBC properties were found to be exaggerated in blood-type O hospitalized COVID-19 subjects compared to blood-type A. These data indicate that altered RBC features in hospitalized COVID-19 subjects burden the cardiovascular system to maintain O2 delivery homeostasis, which appears exaggerated by blood type (more pronounced with blood-type O) and likely plays a role in disease pathogenesis.

Erythrocyte osmotic fragility is not linked to vitamin C nutriture in adults with well-controlled type 2 diabetes

Erythrocyte fragility is amplified by oxidative stress and linked to diabetes-specific microvascular disease. Vitamin C supplementation improves glycemic indices in adults with type 2 diabetes (T2D) by improving antioxidant status. This cross-sectional study examined the relationships between vitamin C status and erythrocyte osmotic fragility in adults with or without T2D. Participants provided a fasting blood sample for erythrocyte osmotic fragility testing as a function of hypotonic NaCl concentrations. Additionally, plasma was stabilized with metaphosphoric acid prior to vitamin C analysis using isocratic reverse-phase UV-HPLC separation. Participants were grouped as diagnosed T2D (n = 14; 36% female; 55.5 ± 8.2 y; 31.5 ± 9.0 kg/m²; HbA1c: 7.4 ± 1.9%; plasma vitamin C: 36.0 ± 12.2 μM) or no diabetes (n = 16; 69% female; 38.7 ± 13.5 y; 26.8 ± 6.6 kg/m²; HbA1c: 5.4 ± 0.3%; plasma vitamin C: 34.8 ± 10.9 μM). Participant characteristics differed between groups only for age and hemoglobin A1c (HbA1c; p < 0.05). All hemolysis parameters were in normal ranges for the participants with T2D, and no significant differences in hemolysis parameters were noted between those with or without T2D. However, among participants with T2D, the NaCl concentration eliciting 50% hemolysis was higher for those with low (<7%) vs. high (>7%) HbA1c values (p = 0.037) indicating a slightly higher erythrocyte fragility in the former group. Vitamin C status did not impact any of the hemolysis parameters in adults with or without T2D. Thus, erythrocyte fragility was not elevated in T2D, and vitamin C nutriture was not related to erythrocyte fragility in adults with well-controlled T2D.

Effect of microaggregate filter passage on feline whole blood stored for 35 days

OBJECTIVES

The aim of this study was to compare the characteristics of fresh and stored feline red blood cells (RBCs) after passage through an 18 μm microaggregate filter.

METHODS

Nine cats were recruited for a single blood donation using an open collection system. A simulated transfusion using a syringe driver and microaggregate filter was performed over 2 h with half the blood on the day of donation and the other half after 35 days of storage. Differences in haematological parameters, haemolysis percentage and osmotic fragility (OF) were compared on the day of donation pre-filter passage (D0-) vs day of donation post-filter (D0+) or day 35 storage pre-filter (D35-) and post-filter (D35+). Blood was cultured at D0+ and D35+.

RESULTS

There were no statistically significant differences in the D0- vs D0+ comparisons. There were statistically significant (P <0.05) increases in haemolysis percentage, red cell distribution width (RDW) percentage and mean OF, and decreases in packed cell volume (PCV), RBC count, haemoglobin and haematocrit for D0- vs D35-. The same was found for D0- vs D35+ with the addition of a significant increase in mean cell haemoglobin (MCH). For D35- vs D35+ only MCH significantly increased. At day 35, 6/9 units had haemolysis percentages that exceeded 1%. This increased to 8/9 of stored units post-filter passage. All blood units cultured negative.

CONCLUSIONS AND RELEVANCE

Fresh RBCs exhibited no in vitro evidence of injury following passage through an 18 μm microaggregate filter. Increased MCH was observed in the stored blood and may represent haemolysis induced by the filter. All other changes can be explained by storage lesion rather than filter passage. The findings highlight the importance of blood banking quality controls and the need for further research to assess the effects of transfusion technique, specifically filter passage, on storage lesion-affected feline blood.

Different Involvement of Band 3 in Red Cell Deformability and Osmotic Fragility-A Comparative GP.Mur Erythrocyte Study

GP.Mur is a clinically important red blood cell (RBC) phenotype in Southeast Asia. The molecular entity of GP.Mur is glycophorin B-A-B hybrid protein that promotes band 3 expression and band 3–AQP1 interaction, and alters the organization of band 3 complexes with Rh/RhAG complexes. GP.Mur+ RBCs are more resistant to osmotic stress. To explore whether GP.Mur+ RBCs could be structurally more resilient, we compared deformability and osmotic fragility of fresh RBCs from 145 adults without major illness (47% GP.Mur). We also evaluated potential impacts of cellular and lipid factors on RBC deformability and osmotic resistivity. Contrary to our anticipation, these two physical properties were independent from each other based on multivariate regression analyses. GP.Mur+ RBCs were less deformable than non-GP.Mur RBCs. We also unexpectedly found 25% microcytosis in GP.Mur+ female subjects (10/40). Both microcytosis and membrane cholesterol reduced deformability, but the latter was only observed in non-GP.Mur and not GP.Mur+ normocytes. The osmotic fragility of erythrocytes was not affected by microcytosis; instead, larger mean corpuscular volume (MCV) increased the chances of hypotonic burst. From comparison with GP.Mur+ RBCs, higher band 3 expression strengthened the structure of RBC membrane and submembranous cytoskeletal networks and thereby reduced cell deformability; stronger band 3–AQP1 interaction additionally supported osmotic resistance. Thus, red cell deformability and osmotic resistivity involve distinct structural–functional roles of band 3.

Comparison of a modified flow cytometry osmotic fragility test with the classical method for the diagnosis of hereditary spherocytosis

BACKGROUND

Hereditary spherocytosis (HS) is the most common inherited hemolytic anemia. The flow cytometric test using eosin-5'maleimide (EMA) is a well-established diagnostic method. However, in order to improve HS detection, it is recommended that EMA and an osmotic fragility test (OFT) both be performed. OFT is time consuming and labor intensive. We used a flow cytometric (FOFT) adaptation of the classical OFT reported by Yamamoto. We compare the FOFT to the classical OFT including practical data and propose options for simplifying this method.

METHODS

Suspected and known HS patients and controls were tested by the following methods: EMA, OFT, and FOFT including some modifications.

RESULTS

The FOFT method is robust and correlates to loss of red blood cells. OFT and FOFT gave similar results in healthy controls and four HS patients. Normal range for FOFT in 70 adults is shown and can be used as a reference value. Neonates should have their own normal range defined. Overnight sample incubation at 37°C did not add information to the FOFT results.

CONCLUSION

Our modified Yamomoto FOFT can replace the classic OFT as the addition to EMA for the diagnosis of HS. The use of flow cytometry in both these methods requires small sample volume, is reproducible, simpler, and produces results more rapidly.

Effect of anticoagulants on farmed giant kokopu, Galaxias argenteus (Gmelin 1789) haematological parameters and erythrocyte fragility

We sought to determine a compatible anticoagulant for routine haematological and physiological assessments with giant kokopu (Galaxias argenteus), an endemic New Zealand fish. We observed that blood treated with lithium heparin (LH) rapidly coagulated and haemolysed, making it unsuitable for G. argenteus. Dipotassium ethylenediaminetetraacetic acid (K₂ EDTA) and trisodium citrate (citrate) effectively prevented blood coagulation. K₂ EDTA-treated erythrocytes exhibited the least mean haemolysis and mean corpuscular fragility. Further studies into prolonged storage effects of citrate and K₂ EDTA are recommended to find a compatible anticoagulant for use with G. argenteus blood.

[Salt sensitivity and osmotic fragility are newly specified risk factors for age-related cerebral microangiopathy]

AIM/

To assess individual values of salt sensitivity and osmotic fragility on the patient's erythrocytes and evaluate predictive ability of these parameters in the development of cerebral small vessel disease (CSVD).

MATERIAL AND METHODS

The study included 73 patients with CSVD (48 women, mean age 60.1±6.5 years) and 19 volunteers (14 women, mean age 56.9±5.4 years). Their erythrocytes were used for the measurement of salt-sensitivity by a modified salt blood test and of osmotic fragility by the classical osmotic fragility test. Binary logistic regression was used to assess the ability of salt-sensitivity and osmotic fragility to predict CSVD development. ROC analysis was used to find out the optimal threshold values of these predictors, their sensitivity and specificity.

RESULTS

An increase in salt sensitivity (cut-off: 8.5 mm/h; sensitivity 64%, specificity 74%) and osmotic fragility (cut-off: 0.62 u.a.; sensitivity 52%, specificity 90%) or their simultaneous use (p of the model <0.000001, cut-off 0.62; sensitivity 88%, specificity 68%) are the independent predictors of CSVD. An increase in salt sensitivity and osmotic fragility is also independently associated with the acceleration of severity of white matter hyperintensities according to Fazekas stages (p=0.019 and 0.004, respectively).

CONCLUSION

The possibility of prediction of CSVD according to an increase in salt sensitivity and osmotic fragility allows us to consider them as the risk factors of CSVD. The standardization of these tests for use in clinical practice is necessary to identify the risk group for CSVD and its individual prevention.

β-Carotene-Induced Alterations in Haemoglobin Affinity to O2

β-Carotene (β-Crt) can be dispersed in hydrophobic regions of the membrane of red blood cells (RBC). Its location, orientation and distribution strongly depend on carotenoid concentration. In the present pilot trial (six human subjects involved), it is demonstrated that incubation of RBCs with β-Crt (1.8 × 107 β-Crt molecules per RBC, 50 μmol/L) results in expansion of the membrane of RBCs and slight elongation of the cell. The changes are of statistical significance, as verified by the Wilcoxon test at p < 0.05. They indicate (i) a highly random orientation and location of β-Crt inside the membrane and (ii) a tendency for its interaction with membrane skeleton proteins. The accompanying effect of decreased RBC resistance to lysis is possibly a result of the incorrect functioning of ion channels due to their modification/disruption. At higher β-Crt concentrations, its clustering inside membranes may occur, leading to further alterations in the shape and size of RBCs, with the most pronounced changes observed at 1.8 × 108 β-Crt molecules per RBC (500 μmol/L). Due to the reduced permeability of ions, such membranes exhibit increased resistance to haemolysis. Finally, we show that interactions of β-Crt with the membrane of RBCs lead to an alteration in haemoglobin-oxygen affinity, shifting the oxyhaemoglobin dissociation curve toward higher oxygen partial pressures. If the impact of β-Crt on a curve course is confirmed in vivo, one may consider its role in the fine tuning of O2 transportation to tissues. Hence, at low concentrations, providing unchanged elastic and functional properties of RBCs, it could serve as a beneficial agent in optimising heart performance and cardiovascular load.

Ovine red cell concentrates for transfusion research - is the storage lesion comparable to human red cell concentrates?

BACKGROUND AND OBJECTIVES

Sheep are increasingly being used as a large in vivo animal model of blood transfusion because they provide several advantages over small animals. Understanding the effects of storage duration on ovine (ov) red cell concentrates (RCCs) and how these changes compare with stored human (hu) RCCs is necessary to facilitate clinical translation of research findings.

MATERIALS AND METHODS

OvRCCs (n = 5) collected and processed in standard human blood collection packs, and equivalent huRCCs provided by Australian Red Cross Lifeblood (n = 5), were stored at 2-6°C for 42 days, with samples collected weekly. Haemolysis index was determined by measuring supernatant haemoglobin concentration. Biochemical parameters were evaluated using a blood gas analyser. Energy metabolites and biologically active lipids were measured using commercial assays. Osmotic fragility was determined by lysis in various saline concentrations. Extracellular vesicles were characterized by nanoparticle tracking analysis.

RESULTS

Ovine red blood cells (RBCs) are double in number, smaller in size and more fragile than human RBCs. Haematological values were unchanged throughout storage. In contrast, biochemical and metabolic values, and haemolysis index in three of the five ovRCCs exceeded huRCCs licensing criteria by day 42. Accumulation of extracellular vesicles and biologically active lipids was comparable between huRCCs and ovRCCs.

CONCLUSION

This study documents similarities and differences in the storage lesion of ovRCCs and huRCCs. This new information will guide the design of ovine transfusion models to enhance translation of findings to human transfusion settings.

Red blood cell osmotic fragility in healthy loggerhead and green sea turtles

Loggerhead (Caretta caretta; Cc) and green sea (Chelonia mydas; Cm) turtles admitted to rehabilitation facilities may require blood transfusions for supportive treatment of disorders resulting in life-threatening anemia, but, considering the unique erythrocyte chemistry of sea turtles, standardized donor red blood cell (RBC) storage protocols have not been established. Prolonged cold storage and the effects of various anticoagulant-preservative solutions have been associated with increased RBC osmotic fragility across a broad range of species. Increased RBC fragility in stored RBC products has been associated with acute transfusion reactions. The osmotic fragility test is used to measure erythrocyte resistance to hemolysis while being exposed to a series of dilutions of a saline solution. We obtained baseline measurements for osmotic fragility in healthy Cc and Cm. Osmotic fragility testing was performed on samples from 10 Cc to 10 Cm. Fifty percent (50%) RBC hemolysis was identified at a mean NaCl concentration of 0.38% in both species. Results of our study will help guide future studies evaluating optimal storage solutions for sea turtle blood products.

Haematoprotective and red blood cell membrane stabilizing effects of Justicia carnae leaf extracts in sodium nitrate-treated rats

Objectives Traditionally, Justicia carnae is used in treatment of anaemia. In this study, the haematoprotective effects of ethanol and aqueous leaf extracts of J. carnae were evaluated in sodium nitrate-treated male rats. Methods Acute toxicity values, phytochemical, vitamin B12, vitamin C and iron contents of the extracts were analytically determined. Seventy (70) adult rats divided into seven groups of 10 rats each were assigned specific treatments. Group I served as the normal control, while group II was treated with the induction agent (sodium nitrate (NaNO3), 300 mg/kg body weight) only. Group III was pretreated with fesolate before NaNO3 induction, while groups IV to VII received leaf extracts in addition to induction. The daily oral treatments lasted for 28 days and at the end, the animals were sacrificed and blood samples were collected for haematological studies. Results Results obtained revealed the presence of flavonoids, phenolic compounds, tannins, terpenes, saponins, alkaloids, vitamins C, B12 and iron in both extracts. The LD50 value for each extract was >5,000 mg/kg body weight. There were increased significant co-administration effects (p < 0.05) in red blood cell, packed cell volume, haemoglobin, white blood cells and platelet counts in the extract and fesolate treated groups compared to negative control. Bleeding time values were not significantly altered in all test groups (p > 0.05), but the increased clotting time values were lowered to about normal values following treatment with the extracts. Conclusions The results showed that J. carnae extract has haematoprotective potential and may be a good candidate for haematopoiesis.

Theoretical Bases for the Role of Red Blood Cell Shape in the Regulation of Its Volume

The red blood cell (RBC) membrane contains a mechanosensitive cation channel Piezo1 that is involved in RBC volume homeostasis. In a recent model of the mechanism of its action it was proposed that Piezo1 cation permeability responds to changes of the RBC shape. The aim here is to review in a descriptive manner different previous studies of RBC behavior that formed the basis for this proposal. These studies include the interpretation of RBC and vesicle shapes based on the minimization of membrane bending energy, the analyses of various consequences of compositional and structural features of RBC membrane, in particular of its membrane skeleton and its integral membrane proteins, and the modeling of the establishment of RBC volume. The proposed model of Piezo1 action is critically evaluated, and a perspective presented for solving some remaining experimental and theoretical problems. Part of the discussion is devoted to the usefulness of theoretical modeling in studies of the behavior of cell systems in general.

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.

A "One-Stop" Screening Protocol for Haemoglobinopathy Traits and Iron Deficiency in Sri Lanka

Introduction: The high frequencies of carriers of severe haemoglobinopathies and of iron deficiency in Southeast Asia require reliable and affordable tests to improve on current screening procedures. Objectives: We evaluate a "one stop" approach using the THALCON dichlorophenolindophenol (DCIP) and one-tube osmotic fragility (OF) tests and measurement of Zinc Protoporphyrin (ZPP) to detect and distinguish HbE and β-thalassaemia traits from iron deficiency. We compare findings with current screening practice in Sri Lanka that relies on the identification of low mean red cell volume and/or mean red cell hemoglobin for this purpose. Methods: Between November 2017 and May 2018, we undertook a cross-sectional survey of secondary school students in Gampaha district, Sri Lanka. The THALCON-DCIP and OF tests were compared to capillary electrophoresis (CE), used as a gold standard to detect haemoglobinopathies. ZPP was measured in whole blood. Plasma ferritin and C-reactive protein (CRP) were measured in students with a raised ZPP concentration. Results: We collected venous blood samples from 1,324/1,332 (99.4%) students. The median age of the students was 17 (IQR 16-18) years, all were Sinhalese and 814/1,324 (61.5%) were female. CE identified 3 students with HbE trait and 26 students with β-thalassaemia trait. The THALCON-DCIP test was positive only in the 3 students with HbE (sensitivity 100%, 95% CI 29.2-100.0; specificity 100%, 95% CI 99.7-100.0). The THALCON-OF test identified all 26 students with β-thalassaemia trait (sensitivity = 100%, 95% CI 86.8-100.0) and 287 students with a normal CE result (specificity = 77.9%; 95% CI 75.5-80.1). It was also positive in 2/3 (66.7%) students with HbE trait. Iron deficiency (ZPP > 70 μmol/mol heme) was present in 118/1,240 (9.5%) students with a normal hemoglobin genotype, all of whom had plasma ferritin <15 ng/ml and CRP <5 mg/L. Conclusion: This one-stop approach offers reliable and affordable population screening for both haemoglobinopathy traits and iron deficiency in resource-limited settings where these conditions are common and ensures that iron supplements are targeted only to those who require them. Further work is warranted to refine the OF test to reduce the number of false positive results.

Antioxidant potentials and effects on the hematology and osmotic fragility scores of a polyherbal formulation used in Southeast Nigeria

Background In this study, the hematological and antioxidant potential as well as the osmotic fragility effects of a Nigerian polyherbal formulation were evaluated. Materials and methods A total of 40 fats were divided into four groups of 10 rats each. Group 1 served as the control group, and the rest were assigned increasing daily oral administration of the extract for 28 days. At the end of treatment, blood was collected for hematological and osmotic fragility studies. The free radical scavenging effect of the extract was investigated via different in vitro models as well. Results Results showed that the nitric oxide scavenging and 2,2-diphenyl-1-picrylhydrazyl (DPPH) activities of the extract were significant (p < 0.05) and compared favorably with that of vitamin C. At 200 and 400 μg/mL, the nitric oxide scavenging activities for Ajumbise Polyherbal Extract (APE) were 60.71 ± 0.25% and 59.49 ± 0.98%, respectively, whereas for the same concentrations of vitamin C, 74.60 ± 0.25% and 85.24 ± 0.14 scavenging activities were obtained. The (DPPH) activity at 100 μg/mL was 81.24 ± 0.02% for the extract and 96.22 ± 0.18% for vitamin C. However, at all concentrations, the extract had significantly lower Ferric Reducing Antioxidant Power (FRAP) activity than vitamin C. Red blood cell counts (RBCC), hemoglobin and packed cell volume values (PCV) were significantly lowered only in groups treated with 400 and 800 mg/kg of the extract (p < 0.05), whereas other RBCC parameters and white blood cell counts (WBCC) were not significantly affected (p < 0.05). Platelet (PLT) count was also significantly lowered in all extract-treated groups. The extract also significantly reduced RBCC percentage hemolysis (p < 0.05). Conclusions Ajumbise polyherbal may be free of hematoxicity and may improve the integrity of the RBC membrane due to its appreciable antioxidant activity.

Flow Cytometric Analysis of Erythrocytes Osmotic Fragility in Hereditary Spherocytosis: A Case-Controlled Study Evaluating the Best Anticoagulant, Sample Pre-Treatment and NaCl Concentration for Reliable Screening of this Red Blood Cell Membrane Disorder

BACKGROUND

The cytometric flow osmotic fragility test (FC-OFT) was recently introduced. However, the test is still under development and some variables have not yet been fully tested.

METHODS

The osmotic fragility of hereditary spherocytosis (HS) cases and healthy controls were evaluated by FC-OFT using a series of tubes containing decreasing concentrations of NaCl. The analyses were executed in fresh and incubated (37°C for 24 h) blood samples anticoagulated with EDTA and heparin. The percentages of residual red blood cells were used to plot the osmotic fragility curves. The OF curves of each tested condition were compared using the median corpuscular fragility (MCF). ROC curve analyses identified the most accurate NaCl concentrations for differentiation between HS cases and healthy controls.

RESULTS

FC-OFT curves assumed a sigmoidal dose-response shape and the MCF of cases and controls were different in all instances. MCF comparisons revealed that incubation and anticoagulant have major and minor effects on the FC-OFT, respectively. One hundred percent of sensitivity and specificity was obtained from 5.5 to 6.0 g/L of NaCl in EDTA-treated fresh blood, from 6.0 to 8.0 g/L of NaCl in EDTA-treated incubated blood, and in none of the tested NaCl concentration in heparinized blood.

CONCLUSIONS

EDTA is the anticoagulant of choice for the assay. Incubation at 37°C for 24 h increased its diagnostic capability. The most reliable NaCl concentration for the discrimination of HS case from controls was 6.0 g/L of NaCL in fresh EDTA-treated blood, and was 7.5 g/L of NaCl in incubated EDTA-treated blood. © 2018 International Clinical Cytometry Society.

Susceptibility of density-fractionated erythrocytes to subhaemolytic mechanical shear stress

INTRODUCTION:

Accumulating evidence demonstrates that subhaemolytic mechanical stresses, typical of circulatory support, induce physical and biochemical changes to red blood cells. It remains unclear, however, whether cell age affects susceptibility to these mechanical forces. This study thus examined the sensitivity of density-fractionated red blood cells to sublethal mechanical stresses.

METHODS:

Red blood cells were isolated and washed twice, with the least and most dense fractions being obtained following centrifugation (1500 g × 5 min). Red blood cell deformability was determined across an osmotic gradient and a range of shear stresses (0.3-50 Pa). Cell deformability was also quantified before and after 300 s exposure to shear stresses known to decrease (64 Pa) or increase (10 Pa) red blood cell deformability. The time course of accumulated sublethal damage that occurred during exposure to 64 Pa was also examined.

RESULTS:

Dense red blood cells exhibited decreased capacity to deform when compared with less dense cells. Cellular response to mechanical stimuli was similar in trend for all red blood cells, independent of density; however, the magnitude of impairment in cell deformability was exacerbated in dense cells. Moreover, the rate of impairment in cellular deformability, induced by 64 Pa, was more rapid for dense cells. Relative improvement in red blood cell deformability, due to low-shear conditioning (10 Pa), was consistent for both cell populations.

CONCLUSION:

Red blood cell populations respond differently to mechanical stimuli: older (more dense) cells are highly susceptible to sublethal mechanical trauma, while cell age (density) does not appear to alter the magnitude of improved cell deformability following low-shear conditioning.

Susceptibility of density-fractionated erythrocytes to subhaemolytic mechanical shear stress

INTRODUCTION:

Accumulating evidence demonstrates that subhaemolytic mechanical stresses, typical of circulatory support, induce physical and biochemical changes to red blood cells. It remains unclear, however, whether cell age affects susceptibility to these mechanical forces. This study thus examined the sensitivity of density-fractionated red blood cells to sublethal mechanical stresses.

METHODS:

Red blood cells were isolated and washed twice, with the least and most dense fractions being obtained following centrifugation (1500 g × 5 min). Red blood cell deformability was determined across an osmotic gradient and a range of shear stresses (0.3-50 Pa). Cell deformability was also quantified before and after 300 s exposure to shear stresses known to decrease (64 Pa) or increase (10 Pa) red blood cell deformability. The time course of accumulated sublethal damage that occurred during exposure to 64 Pa was also examined.

RESULTS:

Dense red blood cells exhibited decreased capacity to deform when compared with less dense cells. Cellular response to mechanical stimuli was similar in trend for all red blood cells, independent of density; however, the magnitude of impairment in cell deformability was exacerbated in dense cells. Moreover, the rate of impairment in cellular deformability, induced by 64 Pa, was more rapid for dense cells. Relative improvement in red blood cell deformability, due to low-shear conditioning (10 Pa), was consistent for both cell populations.

CONCLUSION:

Red blood cell populations respond differently to mechanical stimuli: older (more dense) cells are highly susceptible to sublethal mechanical trauma, while cell age (density) does not appear to alter the magnitude of improved cell deformability following low-shear conditioning.

Assessment of the red blood cell proteome in a dog with unexplained hemolytic anemia

A 7-year-old female neutered Jack Russell Terrier was presented to Langford Vets, the University of Bristol, with a history of chronic intermittent lethargy. Investigations and clinical course were compatible with hereditary hemolysis due to a red blood cell membrane defect. Proteomics was used to explore protein alterations in the presence of a hypothesized red blood cell membrane protein deficiency. Proteomic analysis revealed downregulation of the band 3, and alpha- and beta-adducin proteins, and alterations in the red blood cell proteome consistent with previous reports of changes due to the presence of reticulocytosis and ongoing hemolysis. The spectrum of protein alterations identified in the affected dog may be homologous to a band 3 protein deficiency secondary to hereditary spherocytosis, as described in people.

Effect on Morphology, Osmotic Fragility and Electro Kinetic Potential of Erythrocytes in Hypertension

BACKGROUND

Hypertension is a common health problem concerning a large proportion of population and a leading global risk factor for the burden of cardiovascular disease (CVD). The purpose of this study was to assess the efficacy of the erythrocyte zeta potential as a potential additional indicator for cardiovascular disorder risk so that patients with this can be more rapidly identified and treated.

METHODS

In the present study, blood samples were collected in 5% dextrose solution from patients suffering from hypertension and healthy volunteers (Not taken any medication). The mobility of individual RBCs was tracked by equipped Zeta meter-ZM4DAQ software using microscopicallyacquired video images, data were recorded 10 times for each sample and average zeta-potential in mv was recorded.

RESULTS

We found that mean erythrocytic ZP of control group was found to be 23.41 mv (± 1.87) whereas, erythrocytic ZP for Hypertensive patients was found to be 16.05 (±1.72) mV and Hypertensive patients with Diabetes is much lower from 6.96 mV to 22.76 (+3.88) mV along with structural deformities and increased osmotic fragility of erythrocytes.

CONCLUSION

The data suggest that there are morphological changes in erythrocyte structure, increased osmotic fragility along with significantly lower ZP value as compared to that of healthy volunteers which may be the major cause for progression to the development of cardiovascular disease.

The Impact of Biophysical Properties of Erythrocytes on their Aggregation

Erythrocytes aggregation takes places under low shear conditions or at stasis. All suggested mechanisms of erythrocytes aggregation indicated the importance role of fibrinogen and other blood proteins in enhanced erythrocyte aggregation. Recently a special attention is given to the cellular factors that may effect on erythrocytes aggregation. The present study inferred the effect of the cellular properties of erythrocytes on their aggregation. In the present study, aggregation index was calculated by a simple microscopic method. Correlations between erythrocytes aggregation index and mean cell volume, osmotic fragility, electrophoretic mobility, and magnetophoretic mobility were studied. The findings of this study indicated that the aggregation index is significatly correlated to mean cell volume, magnetophoretic mobility, osmotic fragility and electrophoretic mobility. Thus, It is concluded that cellular factors should be taken into consideration when studying the mechanism of erythrocytes aggregation.

Evaluation of OSMOCELLS, a new semi-automatic device for osmotic fragility assessment

INTRODUCTION

The osmotic fragility (OF) test was a central test for the diagnosis of hereditary red blood cell (RBC) disorders (mostly hereditary spherocytosis (HS), but thalassaemia as well). Nowadays although the traditional multitubes method has lost a prominent place, many laboratories still perform such a laboured test, despite the lack of standardization. In fact, the evaluation of OF may offer an inexpensive screening for RBC disorders. We present a new semi-automatic device, allowing the continuous recording of OF, by an updated dialysis method.

METHODS

Repeatability, stability over time, influence of the anticoagulant were evaluated among a population of healthy blood donors. The test was then performed among patients presenting inherited RBC disorders (HS or haemoglobinopathies) where OF is typically altered.

RESULTS

Repeatability was excellent; the parameters were greatly influenced by the nature of the anticoagulant and interestingly appeared stable for 48 h. Patients with RBC disorders displayed the expected profile in regard with their disease: patients with HS all presented an increased OF while patients with haemoglobinopathy displayed resistant profiles.

CONCLUSION

The device offers a substantial improvement in terms of standardization and consistency of the results and may offer a considerable gain for general laboratories.

Safety assessment and antioxidant activity of Lantana montevidensis leaves: Contribution to its phytochemical and pharmacological activity

Lantana camara, the widely studied species, and L. montevidensis, the less studied species of the genus Lantana are both used in traditional medicine for the same purpose (anti-asthma, anti-ulcer, anti-tumor, etc). However, little is known about the toxicity of L. montevidensis and there is limited information on its chemical constituents. Here, we investigated for the first time the genotoxicity and cytotoxicity of the ethanolic (EtOH) and aqueous extracts from the leaves of Lantana montevidensis in human leukocytes, as well as their possible interaction with human erythrocyte membranes in vitro. The antioxidant activities of both extracts were also investigated in chemical and biological models. Treatment of leukocytes with EtOH or aqueous extracts (1-480 µg/mL) did not affect DNA damage index, but promoted cytotoxicity at higher concentrations (240-480 µg/mL). Both extracts did not modify the osmotic fragility of human erythrocytes. The extracts scavenged DPPH radical and prevented Fe²⁺-induced lipid peroxidation in rat's brain and liver homogenates, and this was likely not attributed to Fe (II) chelation. The HPLC analysis of the extracts showed different amounts of polyphenolic compounds (isoquercitrin, gallic acid, catechin, ellagic acid, apigenin, kaempferol, caffeic acid, rutin, quercitrin, quercetin, chlorogenic acid, luteolin) that may have contributed to these effects. These results supported information on the functional use of L. montevidensis in folk medicine.

Erythrocyte osmotic fragility and general health status of adolescent Sprague Dawley rats supplemented with Hibiscus sabdariffa aqueous calyx extracts as neonates followed by a high-fructose diet post-weaning

High-fructose diets (HFD) can cause oxidative damage to tissues including erythrocyte cell membranes. Hibiscus sabdariffa (HS) has protective antioxidant properties. Rats were used to investigate whether the consumption of HS by neonates would result in long-term effects on their erythrocyte osmotic fragility (EOF) and general health when later fed a high-fructose diet post-weaning through adolescence. Eighty of four-day-old Sprague Dawley rat pups were divided randomly into three treatment groups. The controls (n = 27) received distilled water at 10 ml/kg b. w, while the other groups received either 50 mg/kg (n = 28) or 500 mg/kg (n = 25) of an HS aqueous calyx extract orally till post-natal day 14. The rats in each group were weaned and divided into two subgroups; one continued on normal rat chow, and the other received fructose (20% w/v) in their drinking water for 30 days. Blood was collected in heparinised tubes and added to serially diluted (0.0-0.85%) phosphate-buffered saline to determine the EOF. Clinical markers of health status were determined with an automated chemical analyser. HS extracts did not programme metabolism in the growing rats to alter their general health and EOF in response to the HFD.

Vitamin E supplementation fails to impact measures of oxidative stress or the anaemia of feline chronic kidney disease: a randomised, double-blinded placebo control study

This study was designed to test the hypothesis that supplementation with vitamin E, an antioxidant, in cats with chronic kidney disease (CKD), would reduce oxidative stress and its impact on RBC membrane fragility, resulting in these cats maintaining a greater packed cell volume (PCV) compared with CKD cats not receiving supplementation.

Thirty‐six cats with CKD were randomly assigned to receive either daily vitamin E or a placebo for 3 months in a double‐blinded study design.

History and physical examination, blood pressure, complete blood count (CBC), PCV, biochemical profile and urinalysis (UA) were determined. Parameters of oxidative stress and osmotic fragility were measured. Cats were administered vitamin E or placebo once daily for 3 months. Cats were then reassessed and the diagnostics were repeated.

Twenty‐four cats completed the study, 11 in the vitamin E group and 13 in the placebo group. There were no significant differences between the two groups at the start, or upon completion of the study with regard to biochemical parameters, oxidative stress, erythrocyte osmotic fragility or PCV. None of these parameters changed significantly in either group over the treatment period.

Daily supplementation with 30 IU of vitamin E did not affect the measures of oxidative stress or the anaemia seen in cats with CKD.

Attenuation of erythrocyte membrane oxidative stress by Sesbania grandiflora in streptozotocin-induced diabetic rats

The aim of the present study was to investigate the protective effects of Sesbania grandiflora flower (SGF) extract on erythrocyte membrane in Streptozotocin (STZ)-induced diabetic rats. Adult male albino rats of Wistar strain, weighing 190-220 g, were made diabetic by an intraperitonial administration of STZ (45 mg/kg). Normal and diabetic rats were treated with SGF, and diabetic rats were also treated with glibenclamide as drug control, for 45 days. In this study plasma insulin and haemoglobin levels were decreased and blood glucose, glycosylated haemoglobin, protein oxidation, lipid peroxidation markers, and osmotic fragility levels were increased in diabetic rats. Moreover, erythrocytes antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxide, glutathione reductase, glutathione-S-transferase, and glucose-6-phosphate dehydrogenase activities and non-enzymatic antioxidants such as vitamin C, vitamin E, reduced glutathione (GSH), and oxidized glutathione (GSSG) levels were altered. Similarly, the activities of total ATPases, Na(+)/K(+)-ATPase, Ca(2+)-ATPase, and Mg(2+)-ATPase were also decreased in the erythrocytes of diabetic rats. Administration of SGF to STZ-induced diabetic rats reduced blood glucose and glycosylated haemoglobin levels with increased levels of insulin and haemoglobin. Moreover, SGF reversed the protein and lipid peroxidation markers, osmotic fragility, membrane-bound ATPases activities, and antioxidant status in STZ-induced diabetic rats. These results suggest that SGF could provide a protective effect on diabetes by decreasing oxidative stress-associated diabetic complications.

Osmotic fragility of red blood cells, lipid peroxidation and Ca²⁺-ATPase activity of placental homogenates and red blood cell ghosts in salt-loaded pregnant rats

OBJECTIVE

To evaluate the osmotic fragility of red blood cells and the level of lipid peroxidation, the Ca(2+)-ATPase activity of red cell ghosts and placental homogenates from salt-loaded pregnant rats.

METHODS

Salt-loaded pregnant rats received 1.8% NaCl solution ad libitum as a beverage for seven days, starting on 15th day of pregnancy. Then, it was evaluated the level of lipid peroxidation and the Ca(2+)-ATPase activity of placental homogenates and red blood cell ghosts from control and experimental rats. Furthermore, the osmotic fragility of the red blood cells was evaluated by measuring the lysis of these cells when incubated with a NaCl solution with different osmolarities.

RESULTS

It was found that placental homogenates and red blood cell ghosts from experimental pregnant rats showed an increased level of lipid peroxidation and a lowered Ca(2+)-ATPase activity, as compared to control pregnant rats. They also presented an increased osmotic fragility of their red blood cells.

CONCLUSIONS

Salt-loaded pregnant rats showed, similar to preeclamptic women, an increased level of lipid peroxidation and a lowered Ca(2+)-ATPase activity in placental and red blood cells membranes, as well as an increased osmotic fragility of the red blood cells.

Baseline red blood cell osmotic fragility does not predict the degree of post-LVAD hemolysis

Continuous-flow left ventricular assist devices (LVADs) subject elements of the blood to significant stress, resulting in clinically significant and subclinical hemolysis. We sought to prospectively determine whether baseline red-cell osmotic fragility of an advanced heart-failure patient influences the hemolytic response to LVAD support. Osmotic fragility assesses the degree of red-blood-cell hemolysis under varying degrees of osmotic stress. Assays were prospectively obtained on 50 consecutive patients prior to placement of continuous-flow LVADs: HeartMate II (n = 34), Jarvik 2000 (n = 5), HeartWare (n = 6). The mean age of the patients was 60.2 years and 87% were male and 47% were nonischemic. The overall median post-LVAD lactate dehydrogenase (LDH) was 583 (427-965), and there was no difference between devices. Mean hemolysis was 15.68 ± 12.96% at 0.45% NaCl (the inflection point of the osmotic fragility hemolysis curve). A scatter plot did not reveal any relationship between preoperative osmotic fragility and postoperative LDH. Linear regression confirmed no predictive relationship (p = 0.71). In conclusion, preoperative variations in osmotic fragility do not appear to account for differences in hemolysis following ventricular assist device placement. Mechanical forces generated by existing LVADs result in similar levels of biochemical hemolysis, as assessed by LDH, despite baseline differences in a patient's osmotic red-cell fragility.

Flow cytometric analysis of red blood cell osmotic fragility

This study investigated a new method of flow cytometry (FCM) for analysis of red blood cell (RBC) osmotic fragility. Venous peripheral blood collected in a sampling tube coated with EDTA 2Na was analyzed using FCM to determine RBC osmotic fragility. RBCs were represented as a double-peaked forward scatter (FSC) histogram in FCM. RBCs showed ballooning and spherical shape change in hypotonic solutions before hemolysis. The ballooning of RBCs was expressed as a disappearance of the minor peak and by narrowing and a shift to the right of the FSC histogram. The process of hemolysis was expressed as shrinking of the RBC cytogram in the right upper quadrant on the scatter plot of side scatter versus FSC and by emergence of a cell debris cytogram in the left lower quadrant. The ratio of intact RBCs in hypotonic solution was available as an indicator of osmotic fragility. Acidic solution made erythrocytes less tolerant to hypotonic solution by inducing spherical shape change. In conclusion, FCM can be used to assess RBC osmotic fragility.

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.

Characterization of human erythrocytes as potential carrier for pravastatin: an in vitro study

Drug delivery systems including chemical, physical and biological agents that enhance the bioavailability, improve pharmacokinetics and reduce toxicities of the drugs. Carrier erythrocytes are one of the most promising biological drug delivery systems investigated in recent decades. The bioavailability of statin drugs is low due the effects of P-glycoprotein in the gastro-intestinal tract as well as the first-pass metabolism. Therefore in this work we study the effect of time, temperature as well as concentration on the loading of pravastatin in human erythrocytes to be using them as systemic sustained release delivery system for this drug. After the loading process is performed the carriers' erythrocytes were physically and cellulary characterized. Also, the in vitro release of pravastatin from carrier erythrocytes was studied over time interval. Our results revealed that, human erythrocytes have been successfully loaded with pravastatin using endocytosis method either at 25(o)C or at 37(o)C. The loaded amount at 10 mg/ml is 0.32 mg/0.1 ml and 0.69 mg/0.1 ml. Entrapment efficiency is 34% and 94% at 25(o)C and 37(o)C respectively at drug concentration 4 mg/ml. Moreover the percent of cells recovery is 87-93%. Hematological parameters and osmotic fragility behavior of pravastatin loaded erythrocytes were similar that of native erythrocytes. Scanning electron microscopy demonstrated that the pravastatin loaded cells has no change in the morphology. Pravastatin releasing from carrier cell was 83% after 23 hours in phosphate buffer saline and decreased to 72% by treatment of carrier cells with glutaraldehyde. The releasing pattern of the drug from loaded erythrocytes obeyed first order kinetics. It concluded that pravastatin is successfully entrapped into erythrocytes with acceptable loading parameters and moderate morphological changes, this suggesting that erythrocytes can be used as prolonged release for pravastatin.

In vitro effects of anthocyanin extracts from Justicia secunda Vahl on the solubility of haemoglobin S and membrane stability of sickle erythrocytes

BACKGROUND

Sickle cell disease or drepanocytosis is caused by the polymerisation of abnormal haemoglobin S when oxygen tension decreases. This lead to the changes in the shape of red blood cells and anaemia. It has also been postulated that the red cells of patients with sickle cell disease contain a higher than normal concentration of calcium ions. These ions are bound to membrane proteins resulting in dehydration and loss of red blood cell deformability and cell-to-cell adherence. Anthocyanins extracted from some Congolese plants used in traditional medicine against sickle cell disease have recently been shown to have anti-sickling activity in vitro. Justicia secunda is a plant used in Congo by Jehovah's Witnesses, well known for their refusal of blood transfusions, against anaemia.

MATERIALS AND METHODS

Emmel, Itano and osmotic fragility tests were used to test the effect of anthocyanin extracts from Justicia secunda leaves on haemoglobin S solubility and sickle cell membrane stability.

RESULTS

Anthocyanins from Justicia secunda were found to possess anti-sickling activity. Treated SS red blood cells recovered a normal, classical biconcave form with a radius of 3.3±0.3 μm, similar to that of normal erythrocytes. The solubility of deoxyhaemoglobin S increased and the osmotic fragility of drepanocytes decreased upon treatment with anthocyanin extracts.

CONCLUSION

These findings suggest that anthocyanin extracts play a role in both stabilising the red blood cell membrane and inhibiting polymerisation of haemoglobin S. This provides a possible molecular basis for earlier reports on the anti-sickling properties of anthocyanins from some Congolese plants and their use in the management of sickle cell disease by Congolese traditional healers.

Antidiabetic and haematinic effects of Parquetina nigrescens on alloxan induced type-1 diabetes and normocytic normochromic anaemia in Wistar rats

BACKGROUND

The plant, Parquetina nigrescens is used in folklore medicine to treat diabetes mellitus and its complications in several parts of West Africa.

OBJECTIVE

To determine the effect of Parquetina nigrescens extract on fasting blood glucose in alloxan-induced diabetic rats.

METHODS

The blood glucose levels, complete blood count, erythrocyte indices and osmotic fragility, body and organ weights were evaluated.

RESULTS

Diabetic rats treated with the extract showed significant (P<0.01) reduction of the blood glucose to levels comparable to that of the non-diabetic control and those treated with chlorpropamide (standard drug). Similarly, there was significant (P<0.01) reduction in the complete blood count in the diabetic rats.

DISCUSSION

The anaemia, leucopenia and thrombocytopenia associated with the diabetes were corrected in the animals treated with the extract and chlorpropamide. The extract also reduced the erythrocyte osmotic fragility, body and organ weights. Parquetina nigrescens demonstrated antidiabetic property by reducing the elevated blood glucose in alloxan treated rats which is comparable to animals that received the standard drug.

CONCLUSION

Paraquetina nigrescens stabilized the erythrocyte membrane, decreased the body weight probably by lowering lipogenesis. However, the mechanism underlying the antidiabetic and haematinic properties of Parquetina nigrescens remains to be elucidated.

Ameliorative effects of Cnidoscolus aconitifolius on alloxan toxicity in Wistar rats

BACKGROUND

Diabetes has been associated with several complications occasioned by oxidative stress. Thus, in treatment of the condition, these complications must also be taken into consideration. This study evaluates the effect of Cnidoscolus aconitifolius complications of diabetes induced by alloxan, on haematology and sperm morphometry using the Wistar rats.

METHODS

Diabetes was induced in 25 rats using alloxan. The diabetic rats were then divided into five groups B-F consisting of five rats per group. Groups C-E were administered with 100 mg/kg, 500 mg/kg and 1000 mg/kg of ethanolic leaves extract of Cnidoscolus aconitifolius, respectively, for four weeks post treatment with alloxan, while group F received Chlorpropamide (Diabenes®, Pfizer). The diabetic rats in group B were not treated while group A served as the non diabetic control.

RESULT

Following treatment with alloxan, there was anaemia, thrombocytopenia and leucopenia, while the sperm count, motility and live/dead ratio were significantly reduced. Sperm morphological abnormalities and erythrocyte osmotic fragility also increased significantly. Following treatment of alloxan treated-rats with the extract, there were significant increases in the PCV, RBC, Hb, WBC, MCV and the platelet values. Erythrocyte osmotic fragility, sperm count, motility and live/dead ratio also improved significantly.

CONCLUSION

Cnidoscolus aconitifolius extract was found to ameliorate the effects of alloxan induced diabetes on the haematology but not on the abnormal sperm morphometry in rats.

Protective role of Withaferin-A on red blood cell integrity during 7,12-dimethylbenz[a]anthracene induced oral carcinogenesis

The aim of the present study was to investigate the protective effect of Withaferin-A on red blood cell integrity during 7,12-dimethylbenz[a]anthracene (DMBA) induced oral carcinogenesis. The protective effect of Withaferin-A was assessed by measuring the status of glycoconjugates, membrane bound enzyme activity and red blood cell osmotic fragility. Oral squamous cell carcinoma was induced in the buccal pouch of Syrian golden hamsters by painting with 0.5% DMBA in liquid paraffin thrice a week for 14 weeks. The levels of glycoconjugates, membrane bound enzyme activity, osmotic fragility and thiobarbituric acid reactive substances (TBARS) were analyzed by using specific colorimetric methods. We observed 100% tumor formation in DMBA painted hamsters. Increase in plasma glycoconjugates at the expense of red blood cell membrane glycoconjugates levels were observed in DMBA painted hamsters as compared to control hamsters. Erythrocytes from DMBA painted hamsters were more fragile than those from control hamsters. The activity of membrane bound enzyme (Na(+) K(+) ATPase) decreased whereas TBARS level was increased in DMBA painted hamsters as compared to control hamsters. Oral administration of Withaferin-A at a dose of 20 mg kg(-1) bw significantly prevented the tumor formation as well as normalized the biochemical variables in DMBA painted hamsters. Our results thus demonstrate the protective effect of Withaferin-A on red blood cell integrity during DMBA induced oral carcinogenesis.

Clerodendron inerme protects cellular integrity during 7,12-dimethylbenz[A]-anthracene induced hamster buccal pouch carcinogenesis

Aim of the present study was to investigate the protective effect of Clerodendron inerme on cellular integrity by measuring the status of glycoconjugates, lipids, osmotic fragility, and membrane bound enzyme activity in 7,12-dimethylbenz (a) anthracene (DMBA)-induced oral carcinogenesis. Oral squamous cell carcinoma was induced in the buccal pouch of Syrian golden hamsters by painting with 0.5% DMBA in liquid paraffin thrice a week for 14 weeks. The levels of glycoconjugates, lipids, osmotic fragility and membrane bound enzyme activity were analyzed by using specific colorimetric methods. We observed 100% tumor formation in DMBA painted hamsters. Altered glycoconjugates and lipid pattern were observed in DMBA painted hamsters as compared to control hamsters. Erythrocytes from DMBA painted hamsters were more fragile than those from control hamsters. The activity of membrane bound enzyme (Na(+) K(+) ATPase) decreased in DMBA painted hamsters as compared to control hamsters. Oral administration of aqueous leaf extract of Clerodendron inerme (CiALet) at a dose of 500 mg/kg body weight significantly prevented the tumor formation and histopathological abnormalities as well as normalized the above said biochemical variables in DMBA painted hamsters. Our results thus demonstrate the protective effect of Clerodendron inerme on cellular integrity during DMBA induced oral carcinogenesis.

Focal erythrocyte membrane perturbations caused by nitroxide lipid analogues

Three classes of lipoidal nitroxide spin probes reversibly perturb erythrocyte membranes at low concentrations (10(-10)-10(-5) M). This is manifest in (a) decreased osmotic fragility and (b) alterations of surface topology. At bulk phase nitroxide concentrations providing maximal osmotic stabilization, the erythrocytes exhibit a classic echinocyte morphology. At nitroxide concentrations very slightly higher than those yielding minimal osmotic fragility (10(-5)-10(-4) M), the cellus undergo a sphering reaction and lyse. The morphologic sequence seen in intact cells is not observed in erythrocyte ghosts. We suggest that the spin probes initially concentrate in focal domains, which expand into echinocytic protrusions primarily due to localized weakening of membrane cohesion. We propose that cell lysis involves an irreversible breakdown in membrane domain structure.