Choice of Iron in Hemoglobin
There is an important question which constantly comes back while discussing the need and choice for minerals by the body and the function of these minerals in metabolism. One of the most life stirring choices that nature did make is the choice for Iron as part of the Hemoglobin group. To understand the choice of iron a logical processes is followed. Nature is controlled by different powers. These main powers are: · Gravity · Air pressure · Electricity · Magnetism Beside other powers, it is needed to face these external forces as important to natural choices for the metabolism. The choice of the most important mineral in the body is one issue that needs to be understood. Nature has a wide variety of minerals to choose from to select important carriers of O2 in the human body. It chose Iron (Fe). All other minerals do play a role in the metabolism, structural build up, functionality in a minor or major role. It is beside the goal of the website to address each separate mineral to explain. The conclusion is that Fe is the best option stays put. Nature did make the right choice. The hemoglobin and myoglobin molecules are large, complex proteins, an active site is a non-protein group called heme. The heme consists of a flat organic ring surrounding an iron atom. The organic part is a porphyrin ring based on porphin (a tetrapyrrole ring). Oxygenated hemoglobin (found in blood from arteries) is bright red, but without oxygen present (as in blood from veins), hemoglobin turns a darker red. Venous blood is often depicted as blue in color in medical diagrams, and veins sometimes look blue when seen through the skin. The appearance of blood as dark blue is a wavelength phenomenon of light, having to do with the reflection of blue light away from the outside of venous tissue if the vein is ~0.02 inches deep or more. The iron atom in heme binds to the 4 nitrogen atoms in the center of the porphyrin ring, but this leaves two free bonding sites for the iron, one on either side of the heme plane. The heme group is located in a crevice in the myoglobin molecule, surrounded by non-polar residues except for two polar histidines. One of the free binding sites of iron is joined to one of these histidines, leaving the final bonding site on the other side of the ring available to bond with oxygen. The second histidine group is nearby and serves several purposes. It modifies the shape of the crevice in a way that only small molecules can get in to react with the iron atom, and it helps to make the reaction reversible, such that the oxygen can be released when required by nearby tissues. Both O2 and CO2 bind reversibly to hemoglobin, but certain other molecules, like carbon monoxide, are small enough to fit into the protein crevice, but form such strong bonds with the iron that the process is irreversible. Thus high concentrations of CO rapidly use up the body’s limited supply of hemoglobin molecules and prevent them from binding to oxygen. This is why CO is poisonous. Hemoglobin binding affinity for CO is 200 times greater than its affinity for oxygen, meaning that small amounts of CO dramatically reduces hemoglobin’s ability to transport oxygen. Only 3 mineral metals are sensitive, to an extent, to ferromagnetism; Iron, Cobalt, and Nickle. The prefix ferro- refers to iron, because permanent magnetism was first observed in lodestone, a form of a natural iron ore called magnetite, Fe3O4. All other materials are influenced to some extent by a magnetic field, by several other types of magnetism. The magnetic state (or magnetic phase) of a material depends on temperature and other variables such as pressure and the applied magnetic field. A material may exhibit more than one form of magnetism as these variables change. The magnetic behavior of a material depends on its structure, particularly its electron configuration, for the reasons mentioned above, and also on the temperature. At high temperatures (such as in the body), random thermal motion makes it more difficult for the electrons to maintain alignment. A general description of magnetism as the action is given with the following: When a material is put in a magnetic field, the electrons circling the nucleus experience, in addition to their Coulomb attraction to the nucleus, a Lorentz force from the magnetic field. Depending on which direction the electron is orbiting, this force may increase the centripetal force on the electrons, pulling them in towards the nucleus, or it may decrease the force, pulling them away from the nucleus. This effect systematically increases the orbital magnetic moments that were aligned opposite the field and decreases the ones aligned parallel to the field (in accordance with Lenz’s law). This results in a small bulk magnetic moment, with an opposite direction to the applied field. The force of magnetism is determined by the magnetic moment, a dipole moment within an atom which originates from the angular momentum and spin of electrons. Materials have different structures of intrinsic magnetic moments that depend on temperature; the Curie temperature is the critical point at which a material’s intrinsic magnetic moments change direction. Magnetic moments are permanent dipole moments within the atom which are made up from electron’s angular momentum and spin, by the relation μl = el/2me (me here is mass of an electron), (μl = magnetic moment) and (l is angular momentum) this ratio is called as a gyromagnetic ratio. Electrons inside atoms contribute magnetic moments from their own angular momentum and from their orbital momentum around the nucleus. Magnetic moments from the nucleus are insignificant in contrast to magnetic moments from electrons. Thermal contribution results in higher energy electrons causing disruption to their order and alignment between dipoles to be destroyed. To explain this little inside on the different laws is needed: · Coulomb’s law is a law of physics for quantifying the amount of force with which stationary electrically charged particles repel or attract each other. · Lorentz force is the combination of electric and magnetic force on a point charge due to electromagnetic fields. A particle of charge q moving with velocity v in the presence of an electric field E and a magnetic field B experiences a force · Bohr–van Leeuwen theorem states that when statistical mechanics and classical mechanics are applied consistently, the thermal average of the magnetization is always zero. This makes magnetism in solids solely a quantum mechanical effect and means that classical physics cannot account for diamagnetism. · Curie temperature (TC), or Curie point, is the temperature above which certain materials lose their permanent magnetic properties, to be replaced by induced magnetism. The Curie temperature is named after Pierre Curie, who showed that magnetism was lost at a critical temperature. A ferromagnet, like a paramagnetic substance, has unpaired electrons. However, in addition to the electrons’ intrinsic magnetic moment’s tendency to be parallel to an applied field, there is also in these materials a tendency for these magnetic moments to orient parallel to each other to maintain a lowered-energy state. Thus, even in the absence of an applied field, the magnetic moments of the electrons in the material spontaneously line up parallel to one another. Every ferromagnetic substance has its own individual temperature, called the Curie temperature, or Curie point, above which it loses its ferromagnetic properties. This is because the thermal tendency to disorder overwhelms the energy-lowering due to ferromagnetic order. This is the main reason why the human body is only very slightly magnetic and have huge magnetic fields as an MRI scan machine nearly no effect on the body. The human body has a specific pH dependency. As mentioned pH is a semi-electric potential. Fe (Iron) is able to function well in all pH levels. This is not the case for Nickel neither Cobalt. Both metals act differently at changing pH levels. Their stability in chelation is weak, which makes them less of a choice for being a carrier of a third easy connect / easy release component such as O2. Christian Bohr stated that at lower pH (more acidic environment, e.g., in tissues), hemoglobin would bind to oxygen with less affinity. Since carbon dioxide is in direct equilibrium with the concentration of protons in the blood, increasing blood carbon dioxide content, according to the Bohr effect, causes a decrease in pH, which leads to a decrease in affinity for oxygen by hemoglobin (and easier oxygen release in capillaries or tissues). For example, without the Bohr effect, a human could not walk or run for even 3-5 minutes. Why? In normal conditions, due to the Bohr effect, more oxygen is released in those muscles, which generate more CO2. Hence, these muscles can continue to work with the same high rate. Toxicity: Cobalt and Nickle are both toxic to the metabolism and easily pass the toxic threshold of the body. As hemoglobin enters every part of the body and interacts everywhere a level of toxicity of the host carriers of O2 would be seriously dangerous for the body. Since everything in the human body is based on electric current it is important to choose a mineral that is a not a strong conductor but has higher resistivity activity at given physical temperature ( 36 / 37 degree) and pH level in the body. The blood is a transport system and not a part of the neural transmission system. If the blood becomes a conductor of electrical currency, the powers of the neural system will be diluted and less effective.
The relative atomic weight also has a factor in the choice of elements: Iron Atomic weight: 55.847 Nickel Atomic weight: 58.693 Cobalt Atomic weight: 58.9332 One of the reasons is the formerly mentioned powers of gravity which influence the circulation of the blood. A lower atomic weight gives a lesser total weight. Directly after the importance of the atomic weight, the configuration Cobalt: Electrons: 27 Protons: 27 Neutrons in most abundant isotope: 32 Nickel: Electrons: 28 Protons: 28 Neutrons in most abundant isotope: 30 Iron: Electrons: 26 Protons: 26 Neutrons in most abundant isotope: 30 There is only a little difference of 1 or 2 electrons which is of minimal influence on the total of powers. The connective power to the most important oxidant (O2) is the weakest with Fe. The many different electrical configurations of Fe gives the body the opportunity – in the gelation of the hemoglobin group – to maximize the connective O2 possibility to 4 – O2 per hemoglobin group, which cannot be reached with other metals. The body is air pressure sensitive. Although the percentage of oxygen in the inspired air is constant at different altitudes, the fall in atmospheric pressure at higher altitude decreases the partial pressure of inspired oxygen and the driving pressure for gas exchange in the lungs. An ocean of air is present up to 9-10 000 m, where the troposphere ends and the stratosphere begins. The weight of air above a person is responsible for the atmospheric pressure, which is normally about 100 kPa at sea level. This atmospheric pressure is the sum of the partial pressures of the constituent gases, oxygen, and nitrogen, and also the partial pressure of water vapor (6.3 kPa at 37°C). As oxygen is 21% of dry air, the inspired oxygen pressure is 0.21×(100−6.3)=19.6 kPa at sea level. Atmospheric pressure and inspired oxygen pressure fall roughly linearly with altitude to be 50% of the sea level value at 5500 m and only 30% of the sea level value at 8900 m (the height of the summit of Everest). A fall in inspired oxygen pressure reduces the driving pressure for gas exchange in the lungs and in turn produces a cascade of effects right down to the level of the mitochondria, the final destination of the oxygen. Initially, traveling to altitude hemoglobin concentrations rise through a fall in the plasma volume due to dehydration. Later, hypoxia stimulates the production of erythropoietin by the juxtaglomerular apparatus of the kidney so hemoglobin production increases and hemoglobin concentrations may rise to 200 g/l. The increased viscosity of the blood coupled with increased coagulability increases the risk of stroke and venous thromboembolism. In every part it is possible to conclude that Iron was good – maybe the best possible – choice of nature for the human body. It is very important at all time to control Fe levels during each age. While aging the ability of Fe availability (through digestion) becomes lesser. Additional Fe is advised, this said it strongly depends on physical fitness, altitude, and air quality. REFERENCES
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The importance of Blood in aging
Defining and detecting anemia Anemia means having a lower-than-normal count of red blood cells circulating in the blood. Red blood cells are always counted as part of a “Complete Blood Count” (CBC) test, which is a very commonly ordered blood test. A CBC test usually includes the following results: o White blood cell count (WBCs): the number of white blood cells per microliter of blood o Red blood cell count (RBCs): the number of red blood cells per microliter of blood o Hemoglobin (Hgb): how many grams of this oxygen-carrying protein per deciliter of blood o Hematocrit (Hct): the fraction of blood that is made up of red blood cells o Mean corpuscular volume (MCV): the average size of red blood cells o Platelet count (Plts): how many platelets (a smaller cell involved in clotting blood) per microliter of blood
A “normal” level of hemoglobin is usually in the range of 14-17gm/dL for men, and 12-15gm/dL for women. However, different laboratories may define the normal range slightly differently.
Anemia is often described as: o Microcytic: red cells smaller than normal o Normocytic: red cells of a normal size o Macrocytic: red cells larger than normal
Symptoms of anemia The red blood cells in the blood use hemoglobin to carry oxygen from the lungs to every cell in the body. When a person doesn’t have enough functioning red blood cells, the body begins to experience symptoms related to not having enough oxygen. Common symptoms of anemia are: o fatigue o weakness o shortness of breath o high heart rate o headaches o becoming paler, which is often first seen by checking inside the lower lids o lower blood pressure (especially if the anemia is caused by bleeding)
The most common causes of anemia Compared to most cells in the body, normal red blood cells have a short lifespan: about 100-120 days. A healthy body must produce red blood cells. This is done in the bone marrow and takes about seven days, then the new red blood cells work in the blood for 3-4 months. Once the red blood cell dies, the body recovers the iron and reuses it to create new red blood cells.
Anemia happens when something goes wrong with these normal processes. In kids and younger adults, there is usually one cause for anemia. But in older adults, it’s quite common for there to be several co-existing causes of anemia.
The decrease in immune function mediated by lymphocytes is the most significant change with aging. Thymus involution occurs after puberty and total thymic atrophy occurs by late middle age. With these changes, thymic-mediated T lymphocyte development disappears and older individuals are dependent on their existing T lymphocyte pool to mediate T cell-dependent immune responses. In the absence of thymic function, the number of naive T cells decreases in older individuals and memory T cells are the predominant type. B lymphocyte function is dependent on T cell accessory roles and the decreased ability to generate antibody responses, especially to primary antigens, may be the result of T cell inadequacies rather than an intrinsic fault of B lymphocytes.
Natural killer cells are increased in number, but their function is disturbed. Delayed hypersensitivity reactions are reduced in the elderly. These immunologic deficits are correlated with overall mortality in individuals over age 60. Serum immunoglobulin M and G concentrations do not change significantly in older people. Serum IgA levels increase with age. An increased prevalence of autoantibodies (e.g., anti-IgG rheumatoid factor) occurs in older people. Monoclonal plasma immunoglobulins (essential monoclonal gammopathy) are found with increasing frequency with age, reaching three percent in people over age 70 and nearly six percent in those from 80 to 89.
Few pieces of advice on the treatment of anemia: · Exercise. Moving strengthens bones, improves marrow quality and production of red blood cells. · Eat Iron-rich foods · Use the Sun as energy and vitamin source. Take the time to “enjoy” the sun. · Electrostimulation (also possible in clothing) · Water treatment (Death sea) |