Effects of Long-Term Alpha-mangostin Supplementation on Hyperglycemia and Insulin Resistance in Type 2 Diabetic Rats Induced by High Fat Diet and Low Dose Streptozotocin.
OBJECTIVE
The present study investigated the effects of long-term supplementation of alpha-mangostin (MG; a xanthone isolated from mangosteen fruit) on hyperglycemia, and insulin resistance in type 2 diabetic rats.


METHODS
Type 2 diabetes (DM2) was induced in male Sprague-Dawley rats by feeding high fat diet for three weeks followed by an IP injection of low dose streptozotocin. The rats were divided into four groups: control and diabetes without or with alpha-MG supplementation (CON, DM2, CON-MG and DM2-MG group, respectively). Alpha-MG was administered by gavage feeding in the amount of 200 mg/kg BW/day for 8 or 40 weeks. Fasting blood glucose, plasma HbA1c, cholesterol, and triglyceride were determined in all groups of rats. Serum insulin, calculated HOMA-IR and Oral glucose tolerance test were also carried out.


RESULTS
The results showed that both 8 and 40 weeks DM2 groups had a significant increase in fasting blood glucose, HbA1c, plasma cholesterol and triglyceride compared with their aged-match control groups. Furthermore, the serum insulin and HOMA-IR were significantly elevated in 8 weeks DM2 whereas these two parameters were significantly decreased in 40 weeks DM2 group compared with their aged-match CON groups (p < 0.001). The OGTT showed impaired glucose tolerance in DM2 groups. Interestingly, alpha-MG supplemented DM2-MG group had significantly decreased levels of fasting blood glucose, HbA1c, plasma cholesterol, triglyceride when compared with the untreated DM2 groups. Supplementation of alpha-MG for 40 weeks in DM2-MG group showed significantly increase serum insulin levels compared with that of DM2 group (p < 0.001). Moreover alpha-MG supplemented DM-MG group demonstrated a better glucose tolerance pattern which was different from that of DM2 group at both 8 weeks and 40 weeks experimental periods.


CONCLUSIONS
Long-term alpha-mangostin supplementation has anti-hyperglycemic, anti-hyperlipidemic effects and increase insulin sensitivity by improving beta-cell functions in type 2 diabetes mellitus.
Chantana
C
Mekseepralard
Chonticha
C
Areebambud
Sunit
S
Suksamrarn
Amporn
A
Jariyapongskul
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000178:diet therapy* / Q000209:etiology; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000178:diet therapy* / Q000209:etiology; D004032:Diet; D059305:Diet, High-Fat / Q000009:adverse effects; D019587:Dietary Supplements / Q000032:analysis; D005951:Glucose Tolerance Test; D006801:Humans; D006943:Hyperglycemia / Q000097:blood / Q000178:diet therapy* / Q000209:etiology; D007333:Insulin Resistance; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013311:Streptozocin / Q000009:adverse effects; D044004:Xanthones / Q000008:administration & dosage / Q000494:pharmacology*
D044004:Xanthones; D013311:Streptozocin; C021053:mangostin