Insulin anabolic effects

Figure 12.17 Sites at which insulin stimulates protein synthesis in a muscle. The sites are indicated by 0. Insulin has its anabolic effect on protein synthesis in muscle by affecb ng six processes or reactions (i) it inhibits protein degradab on in the muscle (ii) it sb mulates amino acid transport from the blood into the muscle (iii) it stimulates the inib ab on-reacb on of the pathway for protein synthesis, i.e. formab on of the complex (tRNA-amino acid-mRNA-ribosomal RNA) (iv) it increases the rate of mRNA synthesis, and therefore the number of mRNA molecules (v) it stimulates ribosomal RNA synthesis (vi) it sb mulates elongabon of the pepbde (see Chapter 20).

The anabolic effects of somatropin are mediated by somatomedins or insulin-like growth factors. Somatropin is a synthetic polypeptide identical to the natural occurring growth hormone which stimulates longitudinal growth. Only preparations made with recombinant DNA technology are used nowadays. They can consist of 191 amino acids as growth hormone itself or 192 amino acids with one extra methionine. Somatropin is employed in the treatment... 

Insulin 2 Polypeptides (21 and 30 residues) Glucose uptake, lipogenesis, general anabolic effects... 

Most athletes have heard of IGF-1 (Insulin like growth factor-1) and the amazing anabolic effects it has been reported to have upon protein based tissue such as muscle. Des (1-3) IGF-1 is over 10 times (1000%) more anabolic than IGF-1. Now that is amazing ... 

During the weekend (Saturday - Sunday, about 24 to 48 hours), you eat a high carb, medium fat (30..40%), low protein (10..15%) diet. This causes an insulin spike. While this can increase fat deposits, it moves more nutrients into your muscles, and has an anabolic effect. The important thing is to switch back to the high fat / low carb mode before you put on too much fat. 

Pancreas Insulin General anabolic effects including glucose uptake and lipogenesis... 

The primary targets for insulin are the skeletal and cardiac muscles, adipose tissue, and liver. Insulin has anabolic effects on carbohydrate, lipid, and protein metabolism in these tissues. Insulin induces anabolic reactions while inhibiting catabolic reactions. It also has important effects on growth. 

Insulin has anabolic effects on protein metabolism by stimulating amino acid uptake and protein synthesis and by inhibiting protein breakdown [10]. 

Based on work by Volpi et al., only the EAAs may be necessary to maximize PS following exercise. Ingesting 6 g of EAA after exercise had twice the effect on stimulating net protein balance as did 6 g of AAs made up of 3 g of NEAAs and 3 g of EAAs. In addition, when 35 g of CHO was added to the 6 g of EAAs, the anabolic effect was less than that produced by the EAAs alone (Figure 15.12), which may be related to the increased insulin resulting in AA rranoval by the splanchnic bed. 

Insulin. Insulin is a peptide hormone produced by P-cells of the islets of Langerhans. It is an important anabolic hormone secreted at times when the concentration of nutrient molecules in the blood is high, such as periods following a meal. Its overall effects include allowing the body to use carbohydrates as an energy source and to store nutrient molecules. Specifically, insulin exerts its important actions on the following tissues ... 

Table 11.2 Selected genes whose rate of transcription is altered by binding of insulin to its receptor. In virtually all instances, the ultimate effect is to promote anabolic events characteristic of insulin action. Two-dimensional gel electrophoresis has also pinpointed dozens of proteins of unknown function whose cellular level is altered by insulin...

Il.f.l.1. Insulins. Insulin is the most effective of diabetes medications. Insulin has profound effects on carbohydrate, protein, fat metabolism and electrolytes. It has anabolic and anticatabolic actions. In a state of insulin deficiency, glycogenesis, glucose transport, protein synthesis, triglyceride synthesis, LPL activity in adipose tissue, cellular potassium uptake all decrease on the other hand, gluconeogene-sis, glycogenolysis, protein degradation, ketogene-sis, lipolysis increase. 

Mechanism of Action. Few data are available that describe the effects of anabolic steroids on protein metabolism even fewer data exist for assessment of direct effects of anabolic steroids on lipid metabolism in growing ruminants. The lack of any consistent change in somatotropin, prolactin, insulin, or other metabolic hormones (qv) in a total of 15 studies has been noted (1,38). 

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