Possible Interaction: Insulin and Tryptophan

“ L-tryptophan and L-leucine also modified plasma insulin concentration.”

“Rearrangement of tryptophan residues resulted in significantly increased insulin permeation as compared to that of the parent penetratin.”

“Additionally, it is well known that insulin enhances serotonergic activity in increasing blood-brain barrier transport of tryptophan.”

“The dose-response effect of insulin on tryptophan levels in the elderly was less than in the young (P less than .03), while the response of the LNAA was similar in both age groups.”

“ TP treatment 15 min before the iv administration of regular insulin (0.1 U/kg) significantly blunted the peak corticotropin (ACTH) and cortisol response to hypoglycemia.”

“Combined treatment with TP and insulin (0.05 IU/kg iv) in 10 subjects blunted the hGH response which followed administration of insulin alone.”

“ Tryptophan (4–10 mM) reduces the stimulating effect of insulin on glucose uptake, CO2 output and lactate production by adipose tissue.”

“This study evaluated whether selected hormones, 3,5,3'-triiodothyronine (T3), hydrocortisone (HC), or insulin , would influence the binding of L-tryptophan to rat hepatic nuclei or nuclear envelopes.”

“We evaluated whether selected hormones, 3,5,3'-triiodothyronine (T3), hydrocortisone (HC) or insulin , would influence the binding (saturable, stereospecific, and of high affinity) of L-tryptophan to rat hepatic nuclei or nuclear envelopes.”

“Our results suggest that simultaneous use of Try and insulin has positive effect on the alterations in Try and 5-HT metabolism, that occurred in long-term alloxan diabetic rats despite insulin application.”

“The administration of Try in combination with insulin to diabetic rats altered the levels of brain Try, 5-HT, 5-HIAA and serum concentrations of valine, leucine and isoleucine towards the values in the control (nondiabetic) group.”