Hormones bovine insulin

Biosynthetic Human Insulin from E. coli. Insulin [9004-10-8] a polypeptide hormone, stimulates anaboHc reactions for carbohydrates, proteins, and fats thereby producing a lowered blood glucose level. Porcine insulin [12584-58-6] and bovine insulin [11070-73-8] were used to treat diabetes prior to the availabiHty of human insulin [11061 -68-0]. AH three insulins are similar in amino acid sequence. EH LiHy s human insulin was approved for testing in humans in 1980 by the U.S. EDA and was placed on the market by 1982 (11,12). 

FIGURE 5.17 The hormone insulin consists of two polypeptide chains, A and B, held together by two disulfide cross-bridges (S—S). The A chain has 21 amino acid residues and an intrachain disulfide the B polypeptide contains 30 amino acids. The sequence shown is for bovine insulin. 

Insulin is a polypeptide hormone that consists of two peptide chains bonded by two disulfide bonds. The two chains are designated A and B. The A chain consists of 21 amino acids with a third internal disulfide bond, and the chain contains the remaining 30 amino acids. All vertebrates produce insulin and the structure is similar in these species. For example, the insulin produced in humans and porcine species differs by only one amino acid, and humans and bovine insulin differ by three amino acids. Insulin plays a crucial role in several physiological processes. These include the regulation of sugar in the body, fatty acid synthesis, formation of triglycerides, and amino acid synthesis. 

Insulin rDNA has been very successful. The only problem has arisen in patients who have been using porcine or bovine insulin for a long lime. Some patients who are switched lo rDNA human insulin repon difficulty in "feeling their glucose level." and these patients require extra counseling in the use of the recombinani hormone. 

Finally, the most convincing evidence in support of the absolute safety of BST relates to attempts to develop natural bovine growth hormone as a human drug. Natural BST, extracted from cows, was investigated in the 1950s as a possible injectable treatment for human dwarfism. Bovine insulin used to be the source of human insulin until biotechnology provided a better alternative. Both bovine and human growth hormone have 191 amino acids however, 35% of the amino acids are different between the two species. After inject-... 

The first biotherapeutics— bovine insulin, streptokinase or staphylokinase— were non-human in origin. Subsequent biopharmaceuticals i.e. growth hormone and factor VII) were human in origin. More recently, recombinant proteins i.e. interferon or insulin) have become available. The number of licensed biopharmaceuticals rose from about 10 in 1996 to over 75 in 2006 it is thought that by the end of 2010, approximately half of all newly licensed pharmaceutical agents will be of this type. 

Fig. 3. Plots of the logarithmic capacity factors for hen lysoqnne and several hormonal polyp tides against the volume fraction, p of the organic solvent in water-acetonitrile isocratic mobile phases. Conditions Column, ju-Bondapak Cig flow-rate, 2.0 ml/min primary mobile phases, (a) water - 4 mM sodium sulphate-15 mM orthophosphoric acid, pH 2.2, and (b) water - 4 mM sulphuric add-lS mM orthophosphoric acid-15 mM triethylamine with the acetonitrile content adjusted over the range 0.0-0.8. The polypeptide key is 1 hen lysozyme 2 = porcine glucagon 3 = bovine insulin 4 = bovine insulin fi chain 5 = arginine vasopressin 6 = lysine vasopressin. From [2],...

Figure 24-10 shows the structure of bovine insulin, a more complex peptide hormone that regulates glucose metabolism. Insulin is composed of two separate peptide chains, the A chain, containing 21 amino acid residues, and the B chain, containing 30. The A and B chains are joined at two positions by disulfide bridges, and the A chain has an additional disulfide bond that holds six amino acid residues in a ring. The C-terminal amino acids of both chains occur as primary amides. 

An excellent paper by Sanz-Nebot et al. [1303] focuses on the optimization of separations for therapeutic peptide hormones (e.g., lypressin, oxytocin, bradykinin, triptorelin, buserelin, bovine insulin, salmon calcitonin, met-enkephalin and leu-enkephalin), The optimal mobile phase for a 25°C Cjg column was 35/65/0.1 acetonitrile/water/TFA. The effects of changing solution pH and percent acetonitrile on both k and resolution were plotted. The final separation took 28 min with all analytes but calcitonin eluting prior to 8 min. 

Cell Culture-Derived Media-Derived Protein Impurities. Immunoassays can detect low impurity levels (<1 ppm).4 The ELISA is probably one of the most sensitive analytical methods. If bovine serum is used as a media component, then testing should include ELISAs for bovine serum albumin (BSA), bovine transferrin, bovine fetuin, and bovine IgG. Often hormones and growth factors, such as insulin or insulinlike growth factor, are used as media components. ELISAs should be used to detect and quantitate these residuals in the various production steps as well as in the final product. There are commercially available antibodies to most commonly used media components. If proprietary media components are used, then the same investment in time and effort is required for the production of specific antibodies, as described above for host cell impurities. 

The radioimmunoassay of insulin permits detection of insulin in picomolar quantities. The assay is based on antibodies developed in guinea pigs against bovine or pork insulin. Because of the similarities between these two insulins and human insulin, the assay successfully measures the human hormone as well. 

---