Abstract:

The aim of the present study was to unravel the effects of fucoidan from Acaudina molpadioidea (Am-CHS)
versus Isostichopus badionotus (Ib-CHS) on insulin resistance improvement and related inflammatory cytokines in obese
mice. Male C57BL/6 mice were randomly divided into normal control, model control, positive control, and experimental
groups A, B, C and D. The mice in normal control group were fed standard diet, and those in other groups were fed
high-fat, high-fructose diet. Rosiglitazone (RSG, 1 mg/(kg·d)), low-dose Ib-FUC (20 mg/(kg·d)), high-dose Ib-FUC
(80 mg/(kg·d)), low-dose Am-FUC (20 mg/(kg·d)) and high-dose Am-FUC (80 mg/(kg·d)) were added into the diets of
positive control group, and experimental groups A, B, C and D, respectively. All animals were fed with diets and allowed to
drink water freely for 90 days. After the experiments, white fat weight, fasting serum glucose, serum insulin, serum tumor
necrosis factor-α (TNF-α), interleukin-6 (IL-6), leptin, and adiponectin levels were determined. Results showed that Am-CHS and
Ib-FUC could significantly decrease fat deposition (P ＜ 0.01), blood glucose (P ＜ 0.01) and insulin (P ＜ 0.01) levels, ameliorate
insulin resistance, increase serum adiponectin concentration, lower serum TNF-α (P ＜ 0.01), IL-6 (P ＜ 0.01) and leptin (P ＜ 0.01)
levels, and enhance adiponectin levels (P ＜ 0.01). The effects of Am-FUC were more significant than those of Ib-FUC (P ＜ 0.01).
Both these compounds significantly decreased blood glucose level and ameliorated insulin resistance in insulin-resistant mice, and
the mechanisms might involve the regulation of adipocytokines parasecretion caused by adiposity.

Key words: Acaudina molpadioidea, Isostichopus badionotus, fucoidan, insulin resistance, inflammatory cytokine