Optimization of mice model of painful diabetic neuropathy (PDN)
Abstract: Painful diabetic
neuropathy (PDN) is a complication of long-term Diabetes Mellitus (DM)
characterized by hyperalgesia and allodynia. In streptozotocin (STZ)-induced
diabetic mice, higher dose of STZ and lengthen hiperglycemic condition results
in better model of PDN. However, higher dose of STZ tend to induce mortality.
Evaluate the doses of STZ that caused PDN with less mortality rate and the
timing of pain behavior development in mice model of PDN. Balb/c mice were
divided into non-diabetic and STZ-induced diabetic group. The doses of STZ were
started from 180 mg/kg i.p. Serum glucose levels were measured 7 days after
induction. Mice with glucose levels ≥ 200 mg/dl were considered as diabetic.
Pain behaviour was determined by four method i.e. hot plate, tail flick test,
von Frey fillament and Randall Selitto,measured on week-0 (baseline), 1, 2, 3,
4 and 5. Data were presented as mean±SEM. The mean differences between weeks
were evaluated by One-Way ANOVA and the mean differences between two groups by
independent t-test. STZ doses 180 mg/kg, 150 mg/kg and 120 mg/kg caused 100%
death and STZ 90 mg/kg failed to induce diabetic condition. STZ 110 mg/kg
resulted in 0% mortality while it induced diabetes in 100% mice. Latency time
toward thermal stimulus decreased to 5.8 s at 1st week after the mice become
diabetes (p<0.05) and it was
continued decrease until 4th week. The same result was also showed in tail
flick test and Randal Selitto. The pain sensitivity determined by von Frey
filament decreased to 1.37 g at week 1 (p<0.05) and continued decrease until
5th week. Optimum dose of STZ to induce PDN was 110 mg/kg. Pain behaviour of
diabetic group was observed at 1st week after diabetic and continued until 4th
week.
Keywords: PDN, hot plate, tail
flick test, von Frey fillament, Randall Selitto
Author: Fifteen Aprila Fajrin
Journal Code: jpkedokterangg170297
