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recommended COLLAGEN, ASCORBATE (vitamin C)

Polyol pathway, neuropathy, myo-inositol, t2d, etc

Polyol pathway

“Also called the sorbitol-aldose reductase pathway, the polyol pathway appears to be implicated in diabetic complications, especially in microvascular damage to the retina,[1] kidney,[2] and nerves.[3]

Sorbitol cannot cross cell membranes, and, when it accumulates, it produces osmotic stresses on cells by drawing water into the insulin-independent tissues.[4]


Cells use glucose for energy. This normally occurs by phosphorylation via the enzyme hexokinase. However, if large amounts of glucose are present (as in diabetes mellitus), hexokinase becomes saturated and the excess glucose enters the polyol pathway when aldose reductase reduces it to sorbitol.   Sorbitol dehydrogenase can then oxidize sorbitol to fructose, which produces NADH from NAD+Hexokinase can return the molecule to the glycolysispathway by phosphorylating fructose to form fructose-6-phosphate…. 

While most cells require the action of insulin for glucose to gain entry into the cell, the cells of the retinakidney, and nervous tissues are insulin-independent, so glucose moves freely across the cell membrane, regardless of the action of insulin. [This is not pathological as proven by the very high carbohydrate diets of the Highland New Guinea peoples, the Japanese and Katovans.] The cells will use glucose for energy as normal, and any glucose not used for energy will enter the polyol pathway. When blood glucose is normal (about 100 mg/dl or 5.5 mmol/l), this interchange causes no problems, as aldose reductase has a low affinity for glucose at normal concentrationsWiki.   ANOTHER PHARMA SUPPORTIVE ARTICLE STRESSING HIGH GLUCOSE, GLYCATION, OXIDATIVE DAMAGE, WHILE NOT MENTIONING COLLAGEN, LET ALONE DEFECTIVE COLLAGEN. 

And it gets worse in that in the article on collagen there is no mention of diabetes.


“First, a three-dimensional stranded structure is assembled, with the amino acids glycine and proline as its principal components. This is not yet collagen but its precursor, procollagen. Procollagen is then modified by the addition of hydroxylgroups to the amino acids proline and lysine. This step is important for later glycosylation and the formation of the triple helix structure of collagen. Because the hydroxylase enzymes that perform these reactions require vitamin C as a cofactor, a long-term deficiency in this vitamin results in impaired collagen synthesis and scurvy.[20] These hydroxylation reactions are catalyzed by two different enzymes: prolyl-4-hydroxylase[21] and lysyl-hydroxylase. Vitamin C also serves with them in inducing these reactions. In this service, one molecule of vitamin C is destroyed for each H replaced by OH. [22] The synthesis of collagen occurs inside and outside of the cell. The formation of collagen which results in fibrillary collagen (most common form) is discussed here. Meshwork collagen, which is often involved in the formation of filtration systems, is the other form of collagen. All types of collagens are triple helices, and the differences lie in the make-up of the alpha peptides created in step” https://en.wikipedia.org/wiki/Collagen.   

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