scholarly journals The Multiple Facets of Iron Recycling

Genes ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 1364
Author(s):  
Patryk Slusarczyk ◽  
Katarzyna Mleczko-Sanecka

The production of around 2.5 million red blood cells (RBCs) per second in erythropoiesis is one of the most intense activities in the body. It continuously consumes large amounts of iron, approximately 80% of which is recycled from aged erythrocytes. Therefore, similar to the “making”, the “breaking” of red blood cells is also very rapid and represents one of the key processes in mammalian physiology. Under steady-state conditions, this important task is accomplished by specialized macrophages, mostly liver Kupffer cells (KCs) and splenic red pulp macrophages (RPMs). It relies to a large extent on the engulfment of red blood cells via so-called erythrophagocytosis. Surprisingly, we still understand little about the mechanistic details of the removal and processing of red blood cells by these specialized macrophages. We have only started to uncover the signaling pathways that imprint their identity, control their functions and enable their plasticity. Recent findings also identify other myeloid cell types capable of red blood cell removal and establish reciprocal cross-talk between the intensity of erythrophagocytosis and other cellular activities. Here, we aimed to review the multiple and emerging facets of iron recycling to illustrate how this exciting field of study is currently expanding.

2021 ◽  
Author(s):  
Andrew D. Beale ◽  
Priya Crosby ◽  
Utham K. Valekunja ◽  
Rachel S. Edgar ◽  
Johanna E. Chesham ◽  
...  

AbstractCellular circadian rhythms confer daily temporal organisation upon behaviour and physiology that is fundamental to human health and disease. Rhythms are present in red blood cells (RBCs), the most abundant cell type in the body. Being naturally anucleate, RBC circadian rhythms share key elements of post-translational, but not transcriptional, regulation with other cell types. The physiological function and developmental regulation of RBC circadian rhythms is poorly understood, however, partly due to the small number of appropriate techniques available. Here, we extend the RBC circadian toolkit with a novel biochemical assay for haemoglobin oxidation status, termed “Bloody Blotting”. Our approach relies on a redox-sensitive covalent haem-haemoglobin linkage that forms during cell lysis. Formation of this linkage exhibits daily rhythms in vitro, which are unaffected by mutations that affect the timing of circadian rhythms in nucleated cells. In vivo, haemoglobin oxidation rhythms demonstrate daily variation in the oxygen-carrying and nitrite reductase capacity of the blood, and are seen in human subjects under controlled laboratory conditions as well as in freely-behaving humans. These results extend our molecular understanding of RBC circadian rhythms and suggest they serve an important physiological role in gas transport.


Author(s):  
Chris Cooper

‘What is blood?’ describes the constituent parts of blood: a fluid called plasma in which three different cell types are carried—red cells, white cells, and platelets. Red cells are dominated by the red protein haemoglobin that plays the key role in transporting oxygen from the lungs to the tissue. A lack of red blood cells is called anaemia. A lack of iron is the main cause, iron being required to make a functional haemoglobin protein. White cells, or leucocytes, perform many and varied roles in the body, but all are related to immune defence against pathogens. Platelets have only one function: the prevention of excess bleeding through coagulation.


Author(s):  
D.J.P. Ferguson ◽  
A.R. Berendt ◽  
J. Tansey ◽  
K. Marsh ◽  
C.I. Newbold

In human malaria, the most serious clinical manifestation is cerebral malaria (CM) due to infection with Plasmodium falciparum. The pathology of CM is thought to relate to the fact that red blood cells containing mature forms of the parasite (PRBC) cytoadhere or sequester to post capillary venules of various tissues including the brain. This in vivo phenomenon has been studied in vitro by examining the cytoadherence of PRBCs to various cell types and purified proteins. To date, three Ijiost receptor molecules have been identified; CD36, ICAM-1 and thrombospondin. The specific changes in the PRBC membrane which mediate cytoadherence are less well understood, but they include the sub-membranous deposition of electron-dense material resulting in surface deformations called knobs. Knobs were thought to be essential for cytoadherence, lput recent work has shown that certain knob-negative (K-) lines can cytoadhere. In the present study, we have used electron microscopy to re-examine the interactions between K+ PRBCs and both C32 amelanotic melanoma cells and human umbilical vein endothelial cells (HUVEC).We confirm previous data demonstrating that C32 cells possess numerous microvilli which adhere to the PRBC, mainly via the knobs (Fig. 1). In contrast, the HUVEC were relatively smooth and the PRBCs appeared partially flattened onto the cell surface (Fig. 2). Furthermore, many of the PRBCs exhibited an invagination of the limiting membrane in the attachment zone, often containing a cytoplasmic process from the endothelial cell (Fig. 2).


2021 ◽  
Vol 2 (1) ◽  
pp. 64-69
Author(s):  
HIJRA HIDAYANA ◽  
Suswati Suswati

Hemoglobin is the red pigment-protein contained in red blood cells. The function of hemoglobin is to transport oxygen from the lungs and in the bloodstream to be carried to the tissues. Hemoglobin can increase by increasing the intake of iron in the body. One way to increase hemoglobin can be done by giving method Infused Water Dates. Infused water is a drink consisting of plain water with fresh fruit added and soaking or settling together for a certain time. The making of infused water is carried out by soaking for a period of 0 to 12 hours, so that the infused water becomes a liquid medium that carries more nutrients than ordinary water and will be more easily absorbed by cells and distributed throughout the body (Sidauruk, 2018 ). In several studies, it is stated that dates can increase hemoglobin levels in the blood. Where dates contain iron, vitamin A, vitamin C, protein to form red blood cells. With the method, Infused Water the date palm water becomes alkaline so that it can accelerate the absorption process in the body. The purpose of this study was to determine the effectiveness of dates infused water provision to increase hemoglobin levels of midwifery adolescent girls at Medan Health Polytechnic in 2020. This research was quasi-experimental study using the One Group Pretest-Posttest Without Control Design approach. The sample in this study were 20 respondents of midwifery adolescent girls from Medan Health Polytechnic, using the technique of purposive sampling. The statistical test used wa the Wilcoxon Signed Rank Test because the data was not normal. The results of the Wilcoxon Signed Rank Test obtained the value of P-Value = 0.001. So it can be concluded that the date infused water  is effective in increasing hemoglobin levels of midwifery adolescent girls at Medan Health Polytechnic in 2020.   Keywords: Dates Infused Water, Increased Hemoglobin Levels, Girls Adolescent


2018 ◽  
Vol 315 (2) ◽  
pp. C137-C140 ◽  
Author(s):  
Mariela Arias-Hidalgo ◽  
Samer Al-Samir ◽  
Gerolf Gros ◽  
Volker Endeward

We present here a compilation of membrane CO2 permeabilities (Pco2) for various cell types from the literature. Pco2 values vary over more than two orders of magnitude. Relating Pco2 to the cholesterol content of the membranes shows that, with the exception of red blood cells, it is essentially membrane cholesterol that determines the value of Pco2. Thus, the observed strong modulation of Pco2 in the majority of membranes is caused by cholesterol rather than gas channels.


2020 ◽  
Vol 5 (2) ◽  
pp. 63-71
Author(s):  
Vladimir Nikulin ◽  
Aleksandra Mustafina

The aim of the study is to increase the productive qualities of broiler chickens by including ultrafine silicon oxide into main diet. During the experiment, the biological effect of ultrafine silicon oxide on broiler chickens was estab-lished. Use of ultrafine SiO2 particles for poultry feeding contributed to an increase in the number of red blood cells and content of total protein and albumins. By the end of the experiment, the number of red blood cells in birds in-creased by 17.43% (P≤0.001) – in the blood of birds of the first experimental group, 16.51% (P≤0.01) – the second one, 20.80% (P≤0.001) – the third experimental and 21.71% (P≤0.001) – the fourth experimental group, compared with the indicator of the control group. The amount of total protein in blood serum of chickens of the first and the second experimental groups increased by 1.36-1.39 %, in the third and fourth ones there was a significant (P≤0.05) increase by 5.45 and 3.05%, respectively. The blood glucose content of chickens in the experimental groups is higher by 8.04-23.65% compared to this indicator with ones in the control group. During the experiment feed con-sumption per 1 kg gain of live weight decreased: in the first experimental group by 3.00 % in the second by – 0.50 %, the third – 6.00 % the fourth– by 4.50 %, compared to this with the control group. The chicken’s vibrancy of the first the experimental group was higher by 4.77 %, the second – by 6.20 %, the third – by 19.25 % and the fourth– by 11.59% than in the control one. Consequently, when converting the feed energy into the body energy of a broiler chicken, the energy conversion coefficient of the experimental group of poultry is higher than that of the control one by 7.16-21.76 %. Thus, the most optimal dose for further research was determined.


Blood ◽  
1972 ◽  
Vol 39 (1) ◽  
pp. 81-98 ◽  
Author(s):  
ZELMA MOLNAR ◽  
HENRY RAPPAPORT

Abstract The spleens from two children and one adult with hereditary spherocytosis were studied in the electron microscope. Stagnation of the erythrocytes within the splenic cords is attributable to their lack of plasticity as evidenced by the absence of bilobed, tailed, or squeezed forms in transit through the walls of the sinuses. In contrast to the sections studied by conventional light microscopy, the splenic sinuses in hereditary spherocytosis were not "empty," but contained red blood cells, the majority of which had lost their hemoglobin content. Cordal macrophages were increased in all three cases and were abundant in the splenic cords of the adult patient, causing a further impediment to the rapid passage of erythrocytes. Macrophages, and, to a lesser degree, sinus endothelial cells contained the products of hemoglobin breakdown. The macrophages showed active erythrophagocytosis. Sinus endothelial cells rarely contained intact red blood cells, but showed pronounced pinocytotic activity, a probable mechanism of hemoglobin incorporation. Platelets within the endothelial cells of the sinuses were much more frequently seen in the three cases of hereditary spherocytosis than in control spleens. The presence of ferritin in platelets suggests that they too may play a role in clearing the end products of hemolysis from the spleen.


2019 ◽  
Vol 34 (2) ◽  
pp. 144-153 ◽  
Author(s):  
Andrew D. Beale ◽  
Emily Kruchek ◽  
Stephen J. Kitcatt ◽  
Erin A. Henslee ◽  
Jack S.W. Parry ◽  
...  

Temperature compensation and period determination by casein kinase 1 (CK1) are conserved features of eukaryotic circadian rhythms, whereas the clock gene transcription factors that facilitate daily gene expression rhythms differ between phylogenetic kingdoms. Human red blood cells (RBCs) exhibit temperature-compensated circadian rhythms, which, because RBCs lack nuclei, must occur in the absence of a circadian transcription-translation feedback loop. We tested whether period determination and temperature compensation are dependent on CKs in RBCs. As with nucleated cell types, broad-spectrum kinase inhibition with staurosporine lengthened the period of the RBC clock at 37°C, with more specific inhibition of CK1 and CK2 also eliciting robust changes in circadian period. Strikingly, inhibition of CK1 abolished temperature compensation and increased the Q10 for the period of oscillation in RBCs, similar to observations in nucleated cells. This indicates that CK1 activity is essential for circadian rhythms irrespective of the presence or absence of clock gene expression cycles.


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