Exercise training ameliorates glucosamine-induced insulin resistance in ovariectomized rats.

Abstract

OBJECTIVE:

Glucosamine (GlcN), which has been reported to induce insulin resistance (IR), is a popular nutritional supplement used to treat osteoarthritis in menopausal women. We previously demonstrated that GlcN treatment caused IR in ovariectomized rats by reducing the expression of glucose transport protein subtype 4 (GLUT-4) in skeletal muscle. In the present study, we hypothesized that endurance exercise training can reverse GlcN-induced IR.

METHODS:

Fifty female rats were randomly divided into five groups with 10 rats in each group: (1) sham-operated group; (2) sham-operated group with GlcN treatment for 14 days; (3) ovariectomy (OVX) group; (4) OVX with GlcN treatment; and (5) OVX with GlcN treatment followed by exercise training (running program) for 8 weeks.

RESULTS:

Fasting plasma glucose increased in the OVX + GlcN group, and fasting plasma insulin and the homeostasis model assessment-insulin resistance (HOMA-IR) were significantly higher only in this group. After the rats received exercise training for 8 weeks, no increase in the fasting plasma glucose, insulin, or HOMA-IR was observed. In an intraperitoneal glucose tolerance test, the plasma glucose, plasma insulin, HOMA-IR, and glucose-insulin index were significantly elevated only in the OVX with GlcN treatment group. However, the plasma glucose, plasma insulin, HOMA-IR, and glucose-insulin index decreased after exercise training for 8 weeks, implying that GlcN-induced IR in OVX rats could be reversed through exercise. A histological analysis revealed that exercise training can reduce islet hypertrophy and maintain GLUT-4 in skeletal muscle.

CONCLUSIONS:

Exercise training can alleviate IR in OVX rats treated with GlcN. Islet hyperplasia was subsequently prevented. Preserving GLUT-4 expression may be one of the mechanisms by which exercise prevents IR.

• Authors: Chung-Hwan Chen, Tsang-Hai Huang, Tsung-Lin Cheng, Chi-Fen Chang, Chau-Zen Wang, Meng-Hsing Wu, Lin Kang
• Journal: Menopause (New York, N.Y.) (Menopause) Vol. 24 Issue 6 Pg. 617-623 (06 2017) ISSN: 1530-0374 [Electronic] United States
• PMID: 27922941 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Blood Glucose
• Glucose Transporter Type 4
• Insulin
• Glucosamine

Topics

• Animals
• Blood Glucose (analysis)
• Fasting
• Female
• Glucosamine (pharmacology)
• Glucose Tolerance Test
• Glucose Transporter Type 4 (analysis)
• Hypertrophy
• Insulin (blood)
• Insulin Resistance (physiology)
• Islets of Langerhans (drug effects, pathology)
• Muscle, Skeletal (chemistry, drug effects)
• Ovariectomy
• Physical Conditioning, Animal (physiology)
• Rats
• Rats, Sprague-Dawley