Post Reply 
Thread Rating:
  • 0 Votes - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Silica References
Author Message
James Offline

Posts: 2,827
Joined: Feb 2012
Reputation: 15
Post: #1
Silica References

A bound form of silicon in glycosaminoglycans and polyuronides.

Proc Natl Acad Sci U S A 1973 May ; 70(5): 1608-12

"This study investigated whether Ge can substitute for, or is antagonistic to, Si in bone formation."
"Results confirmed that Ge does not enhance Si deprivation and provided evidence that Ge apparently can replace Si in functions that influence bone composition. When Si was lacking in the diet, calcium and magnesium concentrations of the femur were decreased; this was reversed by feeding either Ge and/or Si."

"We have shown that silicon (Si) deprivation decreases the collagen concentration in bone of 9-wk-old rats. Finding that Si deprivation also affects collagen at different stages in bone development, collagen-forming enzymes, or collagen deposition in other tissues would have implications that Si is important for both wound healing and bone formation."

"Additional evidence of aberrations in proline metabolism with Si deprivation was that liver ornithine aminotransferase was significantly decreased in Si-deprived animals in experiment 2. Findings of an increased accumulation of 14C-proline and decreased total hydroxyproline in implanted sponges and decreased activity of a key enzyme in proline synthesis (liver ornithine aminotransferase) in Si-deprived animals indicates an aberration in the formation of collagen from proline in sites other than bone that is corrected by Si. This suggests that Si is a nutrient of concern in wound healing as well as bone formation."

"Silicon is known to ensure an essential role in the formation of cross-links between collagen and proteoglycans during bone growth."

"whereas silicon (n = 8) induced a significant (P < 0.05) increase in femoral BMD."

"BACKGROUND: Increasing evidence suggests that silicon is important in bone formation."

"It is postulated that the Cu-Si interactions demonstrated in this study could have profound implications on the cardiovascular and skeletal health of birds."

"The differences in calcium digestibility values between the two methods were linearly related to the levels of silica consumption"

"Silicon, generally associated with silicosis, may be necessary for healthy bone and connective tissue."

"The effects of silicic acid, silica and clay minerals on the conversion of amorphous calcium phosphate to hydroxyapatite (HAP) were studied in vitro by a pH drop method. At a concentration range of 0.01-0.1 mM. silicic acid stimulated the rate of HAP transformation by about 30-40%. Silica stimulated the rate of HAP transformation by 33-43% at a concentration range of 0.05-1.5 mg/ml."

"An experiment was performed with the objectives of confirming that silicon status affects bone formation and turnover, and to test the hypothesis that silicon status can affect the interaction between one or more extracellular matrix glycoprotein/s and cell-surface receptors to alter the circulating amount of these glycoproteins, and turnover of type I collagen."

"Plasma sialic acid was increased while osteopontin was decreased by silicon deprivation for eight weeks. Both plasma sialic acid and osteopontin were decreased by the removal of the ovaries. These findings support the hypothesis that silicon functions to affect the actions of extracellular matrix glycoproteins, thus affecting bone formation and turnover."
08-24-2012 01:26 PM
Find all posts by this user Quote this message in a reply
Post Reply 

Forum Jump:

User(s) browsing this thread: 1 Guest(s)