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Structure Of Insulin

Is There Any Chance Of Invention Within Next 5 Years To Replace Insulin Injection By Insulin Tablets?

Is There Any Chance Of Invention Within Next 5 Years To Replace Insulin Injection By Insulin Tablets?

Insulin in the form of a tablet! A doubt that most of us and mores so especially a person dealing with this silent demon of diabetes has. Why do I have to poke my self daily multiple times and deal with this pain all day…why can't they just make into a tablet? They have antibiotic injections and they have tablets for the same, then why not for insulin? Same thoughts occurred to me as a med student! Here how it works.! Insulin is essential to keep our blood sugars in check and all cells need it! It takes a long journey from pancreas to cells via blood stream. In simple words a cell needs insulin to allow the glucose into it. Imagine the cell as say house and the pipeline outside on the road as the main circulatory blood vessel, the water can be compared to the glucose in the pipeline , the water has to enter the house for the people to use it, but now we have a an issue , the entry of water is halted by a valve with a specific key, and this key is insulin, so no key means no water or no Insulin means no entry of glucose…. Water gets accumulated In the pipeline which Is of no use… and the people inside the cell are parched with no water to drink. So we know that Insulin Is a KEY component to survival. Now coming to the question…… An insulin injection when injected, it's done SUBCUTANEOUSLY . Pretty straight forward, we inject it subcutaneously, it gets absorbed slowly into blood stream and reaches the cells. Now coming to oral tablet.. We take a tablet with a drug in it, it reaches the stomach or intestine and it gets absorbed by the stomach or investing lining or receptors in the lining, based on the structure of the drug or the coating used. And it reaches the blood stream. Insulin now is such that when taken orally, it being a simple protein gets digested and Continue reading >>

What Is The Structure Of Insulin - Primary, Secondary, Or Tertiary?

What Is The Structure Of Insulin - Primary, Secondary, Or Tertiary?

This question is not really “making sense” in a traditional way. Let me explain: Proteins are essentially chains of amino acids, small building block-type molecules that each contain an amino (-NH2) and a carboxylic acid group (-COOH) linked with a so-called α-carbon with some sort of identifying residue on it. Amino acids can link together through peptide bonds (R-NH-C(=O)-R). Since all amino acids with the exception of glycine are chiral - meaning they have an asymmetric carbon atom (the aforementioned α-carbon) and thus two mirrored versions of themselves, only one of which serves a use in nature - the structures that build from these amino acids over time are three-dimensional. Now, for the question of primary, secondary and tertiary structure, the following is necessary to learn: the primary structure of a protein is just simply a display of what amino acids are contained in it, in their correct order of linkage (e.g. you’d find something like NH2-Arg-Leu-Ile-Tyr-Phe-Arg-Gly-Arg-COOH). For insulin, this is its primary structure: the secondary structure refers to a larger overview of the amino acid chains. In nature, they can form two kinds of structural elements: α-corkscrews and β-pleated sheets (they can also just link together without any apparent structure). The question of which one is formed depends on the amino acids present in the protein. the tertiary structure of a protein shows it’s entire makeup, which includes corkscrews, pleated sheets, and regular chains. It gives a great overview of all the building blocks, and can look like this (it’s insulin again): So, in principle, the structure of Insulin is neither primary, secondary, nor tertiary, because this is a question that can’t be answered. The simplest response is: it’s (primary) str Continue reading >>

Insulin

Insulin

This article is about the insulin protein. For uses of insulin in treating diabetes, see insulin (medication). Not to be confused with Inulin. Insulin (from Latin insula, island) is a peptide hormone produced by beta cells of the pancreatic islets, and it is considered to be the main anabolic hormone of the body.[5] It regulates the metabolism of carbohydrates, fats and protein by promoting the absorption of, especially, glucose from the blood into fat, liver and skeletal muscle cells.[6] In these tissues the absorbed glucose is converted into either glycogen via glycogenesis or fats (triglycerides) via lipogenesis, or, in the case of the liver, into both.[6] Glucose production and secretion by the liver is strongly inhibited by high concentrations of insulin in the blood.[7] Circulating insulin also affects the synthesis of proteins in a wide variety of tissues. It is therefore an anabolic hormone, promoting the conversion of small molecules in the blood into large molecules inside the cells. Low insulin levels in the blood have the opposite effect by promoting widespread catabolism, especially of reserve body fat. Beta cells are sensitive to glucose concentrations, also known as blood sugar levels. When the glucose level is high, the beta cells secrete insulin into the blood; when glucose levels are low, secretion of insulin is inhibited.[8] Their neighboring alpha cells, by taking their cues from the beta cells,[8] secrete glucagon into the blood in the opposite manner: increased secretion when blood glucose is low, and decreased secretion when glucose concentrations are high.[6][8] Glucagon, through stimulating the liver to release glucose by glycogenolysis and gluconeogenesis, has the opposite effect of insulin.[6][8] The secretion of insulin and glucagon into the Continue reading >>

Which Smart Gel Reduces Diabetes?

Which Smart Gel Reduces Diabetes?

A glucose-dependent shift in the equilibria of PBA (between uncharged and anionically charged; Fig. 1A), when integrated with optimally amphiphilic acrylamide gel backbone (Fig. 1B), could induce a reversible, glucose-dependent change in hydration of the gel (16). The resultant abrupt and rapid change in hydration, under optimized conditions, led to the formation of a gel surfaceemerging, microscopically dehydrated layer, so-called skin layer, providing a mode that is able to effectively switch the release (diffusion) of the gel-loaded insulin (Fig. 1C) (19). The chemical structure of the gel could be further optimized so that it undergoes the above-mentioned performance under physiologically relevant conditions, accompanied by a remarkably gated manner in response to the level of normoglycemia (17, 18, 20, 21). Figure 2A provides images of the gel formed in a macroscopic slab shape that is equilibrated under different glucose environments, that is, hyperglycemic (1000 mg/dl; left) and no glucose (right) conditions. As mentioned above, the chemical structure of this gel has been designed (Fig. 1B) so as to evoke a glucose-dependent change in hydration with a threshold value (of glucose concentration) exactly at normoglycemia (100 mg/dl) under physiological aqueous conditions (pH 7.4; 37C; 155 mM NaCl; fig. S1) (18). Apparently, different sizes of the gel between the two states indicate correspondingly different levels of the hydration. One can also appreciate that the gel retains its opaque (light-scattered) color on its surface when equilibrated without glucose (Fig. 2A, right) due to the occurrence of the skin layer, a surface-localized microscopic dehydration, which recovers into a more hydrated and transparent state when equilibrated under hyperglycemic condition (F Continue reading >>

Structure Of Insulin

Structure Of Insulin

Insulin is composed of two peptide chains referred to as the A chain and B chain. A and B chains are linked together by two disulfide bonds, and an additional disulfide is formed within the A chain. In most species, the A chain consists of 21 amino acids and the B chain of 30 amino acids. Although the amino acid sequence of insulin varies among species, certain segments of the molecule are highly conserved, including the positions of the three disulfide bonds, both ends of the A chain and the C-terminal residues of the B chain. These similarities in the amino acid sequence of insulin lead to a three dimensional conformation of insulin that is very similar among species, and insulin from one animal is very likely biologically active in other species. Indeed, pig insulin has been widely used to treat human patients. Insulin molecules have a tendency to form dimers in solution due to hydrogen-bonding between the C-termini of B chains. Additionally, in the presence of zinc ions, insulin dimers associate into hexamers. These interactions have important clinical ramifications. Monomers and dimers readily diffuse into blood, whereas hexamers diffuse poorly. Hence, absorption of insulin preparations containing a high proportion of hexamers is delayed and somewhat slow. This phenomenon, among others, has stimulated development of a number of recombinant insulin analogs. The first of these molecules to be marketed - called insulin lispro - is engineered such that lysine and proline residues on the C-terminal end of the B chain are reversed; this modification does not alter receptor binding, but minimizes the tendency to form dimers and hexamers. Send comments to [email protected] Continue reading >>

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