PMID 16037305 (http://pubmed.gov/16037305) is titled "High-dose
thiamine therapy counters dyslipidemia and advanced glycation of
plasma protein in streptozotocin-induced diabetic rats". It found that
thiamine had some benefits against AGEs that benfotiamine lacked (in a
rat model):

>We found hydroimidazolone AGE residues derived from glyoxal and
>methylglyoxal, G-H1 and MG-H1, were increased 115% and 68% in STZ
>diabetic rats, with respect to normal controls, and were normalized by
>both thiamine and benfotiamine; whereas N-carboxymethyl-lysine (CML)
>and N-carboxyethyl-lysine (CEL) residues were increased 74% and 118%
>in STZ diabetic rats and were normalized by thiamine only. The lack of
>effect of benfotiamine on plasma CML and CEL residue concentrations
>suggests there may be important precursors of plasma protein CML and
>CEL residues other than glyoxal and methylglyoxal. These are probably
>lipid-derived aldehydes.

I don't have access to the text but wonder how much thiamine was used.

StephenB