Low muscle mass is associated with low insulin sensitivity, impaired pancreatic β cell function, and high glucose excursion in nondiabetic nonobese Japanese women

Satomi Minato-Inokawa; Ayaka Tsuboi-Kaji; Mari Honda; Mika Takeuchi; Kaori Kitaoka; Miki Kurata; Bin Wu; Tsutomu Kazumi; Keisuke Fukuo

doi:10.1016/j.metop.2024.100306

Low muscle mass is associated with low insulin sensitivity, impaired pancreatic β cell function, and high glucose excursion in nondiabetic nonobese Japanese women

Metabol Open. 2024 Jul 30:23:100306. doi: 10.1016/j.metop.2024.100306. eCollection 2024 Sep.

Authors

Satomi Minato-Inokawa^{1

2}, Ayaka Tsuboi-Kaji^{1

3}, Mari Honda^{4

5}, Mika Takeuchi¹, Kaori Kitaoka^{1

6}, Miki Kurata^{1

7}, Bin Wu^{4

8}, Tsutomu Kazumi^{1

4

9}, Keisuke Fukuo^{1

4

7}

Affiliations

¹ Research Institute for Nutrition Sciences, Mukogawa Women's University, Nishinomiya, Hyogo, Japan.
² Laboratory of Community Health and Nutrition, Department of Bioscience, Graduate School of Agriculture, Ehime University, Matsuyama, Ehime, Japan.
³ Department of Nutrition, Osaka City Juso Hospital, Osaka, Japan.
⁴ Open Research Center for Studying of Lifestyle-Related Diseases, Mukogawa Women's University, Nishinomiya, Hyogo, Japan.
⁵ Department of Health, Sports, and Nutrition, Faculty of Health and Welfare, Kobe Women's University, Kobe, Hyogo, Japan.
⁶ Department of Advanced Epidemiology, Noncommunicable Disease (NCD) Epidemiology Research Center, Shiga University of Medical Science, Otsu, Shiga, Japan.
⁷ Department of Food Sciences and Nutrition, Mukogawa Women's University, Nishinomiya, Hyogo, Japan.
⁸ Department of Endocrinology, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China.
⁹ Department of Medicine, Hakuhoukai Kakogawa Hospital, Kakogawa, Hyogo, Japan.

Abstract

Aim: We tested whether skeletal muscle mass is associated with insulin sensitivity, pancreatic β-cell function, and postglucose glycemia.

Methods: Appendicular skeletal muscle mass (ASM) (relative to body size, %ASM) by DXA, surrogate measures of insulin sensitivity, insulin secretion and the disposition index (insulin sensitivity adjusted insulin secretion: a product of the insulinogenic index and Matsuda insulin sensitivity index) inferred from serum insulin kinetics during a 75 g oral glucose tolerance test (OGTT) were evaluated in 168 young and 65 middle-aged women, whose BMI averaged <23.0 kg/m² and HbA1c ≦ 5.5 %.

Results: In two groups of women, %ASM was associated negatively with homeostasis model assessment insulin resistance (HOMA-IR) and 2-h insulin (both p < 0.01 or less). In middle-aged women not in young women, %ASM was associated inversely with the Matsuda index (p < 0.001). In middle-aged women only, it also showed a positive association with the disposition index (p = 0.02) and inverse associations with 1-h and 2-h glucose (both p < 0.01) and area under the glucose concentration curve during OGTT (p = 0.006). On multivariate linear regression analyses, 2-h insulin emerged as a determinant of %ASM independently of HOMA-IR in young women (standardized β: 0.287, p < 0.001, R² = 0.077). In middle-aged women, the Matsuda index emerged as a determinant of %ASM (standardized β: 0.476, p < 0.001) independently of HOMA-IR, log ODI and AUCg and explained 21.3 % of %ASM variability. Post-glucose glycemia and AUCg were higher and log ODI was lower in middle-aged women with low compared with high %ASM.

Conclusion: Low skeletal muscle mass (relative to body size) was associated with low insulin sensitivity in young and middle-aged Japanese women who were neither obese nor diabetic. Middle-aged women with low muscle mass had low disposition index, an early marker of inadequate pancreatic β-cell compensation, and hence high glucose excursion. Low skeletal muscle mass may be associated with the development of type 2 diabetes at a much lower BMI in Japanese people.

Keywords: Glucose excursion; Insulin sensitivity; Japanese people; Relative muscle mass; β-cell function.