Association between the osmotic fragility of erythrocytes and the course of acute myocardial infarction

Aim. To investigate the relationship between the osmotic fragility of erythrocytes and the course of acute myocardial infarction (MI).Methods. An analysis of the osmotic fragility of erythrocytes was conducted using beta-blocker-based osmotic fragility test in sixty-two patients within the first 6 hours after onset of MI symptoms.Results. The results revealed that the patients with increased erythrocyte osmotic fragility experienced more complications after acute MI, such as left ventricular failure and cardiac arrhythmias (ventricular extrasystoles and ventricular tachycardia) (p = 0.026). Moreover, these patients exhibited greater myocardial injury - the concentration of biomarkers of myocardial necrosis, such as creatine phosphokinase, creatine phosphokinase MB and Troponin I was increased - p = 0.009, p = 0.032 and p = 0.001, respectively. In addition to that, the patients with high osmotic fragility had a larger number of hypokinetic and akinetic segments, high impaired myocardial contractility index, and low ejection fraction. The impaired myocardial contractility index was significantly higher in patients with increased erythrocyte osmotic fragility (1.5 (1.22; 1.75) vs 1.12 (1.0; 1.56), U = 157.5, p = 0.032).Conclusion. Increased erythrocyte osmotic fragility in patients was associated with greater myocardial injury, manifesting through the higher concentration of biomarkers of myocardial necrosis in blood, as well as higher number of hypokinetic segments.

Minor Changes in Erythrocyte Osmotic Fragility in Trace Amine-Associated Receptor 5 (TAAR5) Knockout Mice

Trace amine-associated receptors (TAARs) are a group of G protein-coupled receptors that are expressed in the olfactory epithelium, central nervous system, and periphery. TAAR family generally consists of nine types of receptors (TAAR1-9), which can detect biogenic amines. During the last 5 years, the TAAR5 receptor became one of the most intriguing receptors in this subfamily. Recent studies revealed that TAAR5 is involved not only in sensing socially relevant odors but also in the regulation of dopamine and serotonin transmission, emotional regulation, and adult neurogenesis by providing significant input from the olfactory system to the limbic brain areas. Such results indicate that future antagonistic TAAR5-based therapies may have high pharmacological potential in the field of neuropsychiatric disorders. TAAR5 is known to be expressed in leucocytes as well. To evaluate potential hematological side effects of such future treatments we analyzed several hematological parameters in mice lacking TAAR5. In these mutants, we observed minor but significant changes in the osmotic fragility test of erythrocytes and hematocrit levels. At the same time, analysis of other parameters including complete blood count and reticulocyte levels showed no significant alterations in TAAR5 knockout mice. Thus, TAAR5 gene knockout leads to minor negative changes in the erythropoiesis or eryptosis processes, and further research in that field is needed. The impact of TAAR5 deficiency on other hematological parameters seems minimal. Such negative, albeit minor, effects of TAAR5 deficiency should be taken into account during future TAAR5-based therapy development.

Effect of hydro-methanol stem bark extract of Burkea africana on erythrocyte osmotic fragility and haematological parameters in acetaminophen-poisoned rats

Background Burkea africana is a widely used medicinal plant in folkloric medicine in many developing countries of the world. It is useful in the treatment of various ailments including hepatitis, jaundice, diarrhea, stomach aches, abscesses, oedema, epilepsy, bloody diarrhea, gonorrhea, syphilis, toothaches and poisoning. Nevertheless, there are little or no scientific evidence to substantiate this medicinal claim by traditional healers. Burkea africana stem bark was therefore, investigated for its protective or stabilizing effect on erythrocyte membrane in acetaminophen-treated rats. B. africana stem bark was extracted using 80% methanol. Erythrocyte stabilizing effect was studied using erythrocyte osmotic fragility (EOF) test. Thirty (30) male rats were randomly assigned into five (5) groups of six (6) rats each. Groups 1 and 2 served as normal control and negative control (acetaminophen-treated group) respectively. Groups 3, 4 and 5 were pretreated with methanol stem bark extract of Burkea africana (MSBEBA) at doses of 200, 400 and 600 mg/kg body weight respectively once daily for seven (7) days. Blood samples were collected from the animals in all the groups on the 8 day for evaluation of packed cell volume, haemoglobin, red blood cell, white blood cell counts, and differential white blood cell count as well as erythrocyte osmotic fragility. Results The erythrocyte osmotic fragility test showed that there was a significantly (p < 0.05) low percentage hemolysis in the groups pre-treated with the extract when compared with the negative control. The percentage hemolysis was least at 600 mg/kg body weight of the extract. There was also a significant (p < 0.05) increase in the packed cell volume, haemoglobin, red blood cell count at all the doses of the extract used. Neutrophils were significantly (p < 0.05) decreased while lymphocytes were significantly increased in the groups administered MSBEBA 400 and 600 mg/kg body weight. Conclusion Methanol stem bark extract of Burkea africana had protective effect on the red blood cells and also improved haematological parameters. This indicates that Burkea africana may be useful in the treatment of disease conditions that results in hemolytic anemia by stabilizing red erythrocyte membranes and enhancing erythropoiesis.

Seasonal Variation in the Haematological Parameters of the Adult Mallard Duck in a Tropical Environment

Duck production is a growing poultry enterprise in Nigeria and they are mostly reared in extensive management system. However, the haematological profiles as influenced by the tropical environment have not been well documented. The objective of the present study was to examine the seasonal variation in the haematological parameters of the adult Mallard duck in the tropical environment of Nigeria; as they effects duck production adversely. The Erythrocyte, leucocyte and platelet counts, as well as the erythrocyte osmotic fragility of the domestic duck of the mallard breed during the wet and dry seasons in the hot humid tropical environment of the Experimental Animal Unit of the Department of Veterinary Physiology, Biochemistry and Pharmacology, University of Ibadan, Ibadan, Nigeria was investigated. The study showed that the values of the packed cell volume (PCV), mean corpuscular haemoglobin (MCH) and platelet were significantly higher in the dry season than in the wet season, but the red blood cell (RBC), haemoglobin (Hb), mean corpuscular volume (MCV), mean corpuscular haemoglobin concentration (MCHC), total and differential leucocyte values were similar in the two seasons. The erythrocyte fragility was also higher in the dry season. In conclusion the higher PCV, MCH and platelet values in the dry season might have resulted from haemoconcentration occasioned by higher evaporative heat loss, which is a common occurrence in the dry season. The higher erythrocyte fragility could have been the result of stress induced by the high ambient temperature during the dry season, or higher metabolic rate associated with lactic acid accumulation, which has been shown to increase erythrocyte osmotic fragility.

Acute Toxicity and Erythrocyte Osmotic Fragility Studies of Methanol Leaf Extract of Asystasia vogeliana in Rats

Aim: To investigate the phytoconstituents of methanol and petroleum leaf extracts of Asystasia vogeliana (MLEAV and PLEAV), the median lethal dose (LD50) and the effects of MLEAV on body weight, organosomatic indices in vital organs and erythrocyte membrane of Albino Wistar rats during sub-acute administration. Place and Duration of Study: Department of Veterinary Physiology and Pharmacology, University of Nigeria, Nsukka, in 2017. Methodology: The crude extracts of MLEAV and PLEAV were used in determining the qualitative and quantitative analyses. The rats were assigned into four groups and dosed orally with distilled water (0.5 ml/100 g) as Group I, 62.5 mg/kg MLEAV (Group II), 125 mg/kg MLEAV (Group III) and 250 mg/kg MLEAV (Group IV) once daily for 28 days. Blood samples were collected from all the rats via the medial canthus into EDTA bottles for erythrocyte osmotic fragility (EOF) study on day 29. Relative organ-body weight indices of vital organs (spleen, heart, liver and kidney) were also evaluated. Results: MLEAV and PLEAV showed the presence of saponins, flavonoids, phenols, alkaloids, anthraquinones and steroids. The total phenolic contents of MLEAV (3704.30 ± 44.00) significantly increase (P = 0.000) when compared with PLEAV (1349.46 ± 35.25). The LD50 of MLEAV is above 5000 mg/kg. There were significant (P < 0.05) decreases in the body weights of rats in Groups III and IV from 3rd to 4th week when compared with their baseline weights. There were significant (P < 0.05) increases in the relative spleen-body weight in Group IV when compared with other groups. There was no significant change (P > 0.05) in the hemolysis of rats in Group II when compared with the control group at 0.9% NaCl concentration. Conclusions: The findings reveal that MLEAV showed better antioxidant capacity than PLEAV, and that 62.5 mg/kg of MLEAV is safe during the sub-acute administration.