[Effect of sustained release of recombinant rat insulin-like growth factor-1 from poly (lactide-CO-glycolide ) microspheres on bone formation in the peri-implant areas in Goto-Kakizaki rats with type 2 diabetes].
OBJECTIVE
To evaluate the effect of sustained release of recombinant rat insulin-like growth factor-1(rrIGF-1) from poly (lactide-CO-glycolide) (PLGA) microspheres on bone formation in the peri-implant areas in Goto-Kakizaki rats with type 2 diabetes.


METHODS
Type 2 diabetes models were successfully established in 20 male Goto-Kakizaki rats, which were then randomly divided into treatment group (sustained release of rrIGF-1 from PLGA microspheres were loaded on the peri-implant areas, n=10) and diabetic group (loaded with isodose placebo from PLGA microspheres, n=10). Another ten male SD rats served as control group (did not sustain any loading). Titanium implants were inserted into the tibias of 30 diabetic and normal animals. Four, 5, and 8 weeks after implantation, local blood samples around the implants were obtained for the determination of serum osteocalcin (OCN), serum bone specific alkaline phosphatase (B-ALP), and serum procollagen I carboxyterminal propeptide (PICP) with enzyme linked immunosorbent assays.


RESULTS
Four weeks after implantation, OCN, B-ALP, and PICP were significantly lower in both treatment group and diabetic group than in control group(both P<0.05). Five weeks after implantation, serum OCN and B-ALP levels of the diabetic group were significantly lower than those of the other two groups (all P<0.05). Serum PICP levels of both diabetic group and treatment group were significantly lower than that of control group(both P<0.05). The OCN level in the trealment group was significantly higher in the post-operative 5th week than in the post-operative 4th week, while the PICP levels in the diabetic group were significantly lower than those in the treatment group and control group in the post-operative 8th week (both P<0.05).


CONCLUSIONS
Sustained release of rrIGF-1 from PLGA microspheres loaded on the local peri-implant areas can promote bone formation in the peri-implant areas in Goto-Kakizaki rats with type 2 diabetes.
Yu
Miao
M
Department of Oral Implantology, School of Stomatology, Fourth Military Medical University, Xi'an 710032, China.
Hui
Xin-Min
XM
Wang
Feng
F
Zhang
Ning
N
Zhang
He-Peng
HP
Song
Ying-Liang
YL
D000818:Animals; D003692:Delayed-Action Preparations; D015921:Dental Implants; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D004195:Disease Models, Animal; D020007:Implants, Experimental; D007334:Insulin-Like Growth Factor I / Q000008:administration & dosage* / Q000494:pharmacology; D019344:Lactic Acid / Q000008:administration & dosage* / Q000494:pharmacology; D008297:Male; D008863:Microspheres; D010012:Osteogenesis / Q000187:drug effects*; D011100:Polyglycolic Acid / Q000008:administration & dosage* / Q000494:pharmacology; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D051381:Rats; D011919:Rats, Inbred Strains
D003692:Delayed-Action Preparations; D015921:Dental Implants; C548904:insulin-like growth factor-1, rat; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D007334:Insulin-Like Growth Factor I