Insulin fast-acting

Fast-acting insulins Amino acid substitutions generate products that enter the bloodstream more quickly from the site of injection, facilitating product co-administration with a meal rather than administration 30-45 min prior to a meal 11... 

The concentration of insulin present in soluble insulin preparations (i.e. fast-acting insulins), is much higher (approximately 1 x KT2 3 mol I ). At this concentration, the soluble insulin exists as a mixture of monomer, dimer, tetramer and zinc-insulin hexamer. These insulin complexes have to dissociate in order to be absorbed from the injection site into the blood, which slows down the onset of hormone action. 

Figure 11.5 Three-dimensional structure of the engineered fast-acting insulin, Insulin lispro. Structural details courtesy of the Protein Data Bank, http //www.rcsb.org/pdb/...

Insulin lispro - fast-acting, recombinant human Diabetes... 

Another method for aggressive control of blood glucose levels is the use ofinsuiin pumps to cover basal insulin needs plus supplemental dosing at meals with fast-acting insulin. 

Insulin Aspart is a second fast-acting engineered human insulin analogue now approved for general medical use. It differs from native human insulin in that the proline residue has been replaced by aspartic acid. This single amino acid substitution also decreases the propensity of individual molecules to self-associate, ensuring that they begin to enter the bloodstream from the site of injection immediately upon administration. 

Insulin Lispro was the first recombinant fast-acting insulin analogue to gain marketing approval (Table 8.3). It displays an amino acid sequence identical to native human insulin, with one alteration — an inversion of the natural proline lysine sequence found at positions 28 and 29 of the insulin jS-chain. This simple alteration significantly decreased the propensity of individual insulin molecules to self-associate when stored at therapeutic dose concentrations. The dimerization constant for Insulin Lispro is 300 times lower than that exhibited by unmodified human insulin. Structurally, this appears to occur as the change in sequence disrupts the formation of inter-chain hydrophobic interactions critical to self-association. 

Continuous subcutaneous insulin infusion with fast-acting insulin has been used in two cases. 

His blood glucose was 0.6 mmol/1 and he had a respiratory acidosis and dehydration. He recovered with 50 ml of intravenous dextrose 50%. He admitted that he used insulin three times per week and glucocorticoids to support his diet before competitions. This time he had used a fast-acting insulin. 

Mudaliar SR, Lindberg FA, Joyce M, Beerdsen P, Strange P, Lin A, Henry RR. Insulin aspart (B28 asp-insulin) a fast-acting analogue of human insulin absorption kinetics and action profile compared with regular human insulin in healthy nondiabetic subjects. Diabetes Care 1999 22(9) 1501—6. 

Raskin P, Guthrie RA, Leiter L, Riis A, Jovanovic L. Use of insulin aspart, a fast-acting insulin analogue, as the mealtime insulin in the management of patients with type 1 diabetes. Diabetes Care 2000 23(5) 583-8. 

Heller SR, Amiel SA, Mansell PU.K. Lispro Study Group. Effect of the fast-acting insulin analogue lispro on the risk of nocturnal hypoglycemia during intensified insulin therapy. Diabetes Care 1999 22(10) 1607-11. 

Most athletes made excellent progress using only 5 iu of fast acting insulin, 2 times daily. 13 iu was considered an intermediate or advanced level. 

Prostaglandins have shown up in a synthesized form on the black market since a few years ago. I have personally seen amazing transformations in those who had bravely injected PGF-2 site specifically 3-5 times per day. The injections were administered directly into the muscle group trained that day (usually with a fast-acting insulin such as Humulin R or Humalog). Due to extreme soreness, that body part could not be trained for a few days following injections. Since PGF-2 is site-specific, abdominal enlargement does not seem to occur as with IGF-1. 

Insulin analogues Fast acting insulin analogues Long acting insulin analogues... 

Table 1.1. PROPERTIES OF FAST ACTING INSULIN ANALOGUES...

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