AUTHOR=Tuerxun Rukeye , Kamagata Koji , Saito Yuya , Andica Christina , Takabayashi Kaito , Uchida Wataru , Yoshida Seina , Kikuta Junko , Tabata Hiroki , Naito Hitoshi , Someya Yuki , Kaga Hideyoshi , Miyata Mari , Akashi Toshiaki , Wada Akihiko , Taoka Toshiaki , Naganawa Shinji , Tamura Yoshifumi , Watada Hirotaka , Kawamori Ryuzo , Aoki Shigeki TITLE=Assessing interstitial fluid dynamics in type 2 diabetes mellitus and prediabetes cases through diffusion tensor imaging analysis along the perivascular space JOURNAL=Frontiers in Aging Neuroscience VOLUME=16 YEAR=2024 URL=https://www.frontiersin.org/journals/aging-neuroscience/articles/10.3389/fnagi.2024.1362457 DOI=10.3389/fnagi.2024.1362457 ISSN=1663-4365 ABSTRACT=Background and purpose

Glymphatic system in type 2 diabetes mellitus (T2DM) but not in the prodrome, prediabetes (Pre-DM) was investigated using diffusion tensor image analysis along the perivascular space (DTI-ALPS). Association between glymphatic system and insulin resistance of prominent characteristic in T2DM and Pre-DM between is yet elucidated. Therefore, this study delves into the interstitial fluid dynamics using the DTI-ALPS in both Pre-DM and T2DM and association with insulin resistance.

Materials and methods

In our cross-sectional study, we assessed 70 elderly individuals from the Bunkyo Health Study, which included 22 with Pre-DM, 18 with T2DM, and 33 healthy controls with normal glucose metabolism (NGM). We utilized the general linear model (GLM) to evaluate the ALPS index based on DTI-ALPS across these groups, considering variables like sex, age, intracranial volume, years of education, anamnesis of hypertension and hyperlipidemia, and the total Fazekas scale. Furthermore, we have explored the relationship between the ALPS index and insulin resistance, as measured by the homeostasis model assessment of insulin resistance (HOMA-IR) using GLM and the same set of covariates.

Results

In the T2DM group, the ALPS index demonstrated a reduction compared with the NGM group [family-wise error (FWE)-corrected p < 0.001; Cohen's d = −1.32]. Similarly, the Pre-DM group had a lower ALPS index than the NGM group (FWE-corrected p < 0.001; Cohen's d = −1.04). However, there was no significant disparity between the T2DM and Pre-DM groups (FWE-corrected p = 1.00; Cohen's d = −0.63). A negative correlation was observed between the ALPS index and HOMA-IR in the combined T2DM and Pre-DM groups (partial correlation coefficient r = −0.35, p < 0.005).

Conclusion

The ALPS index significantly decreased in both the pre-DM and T2DM groups and showed a correlated with insulin resistance. This indicated that changes in interstitial fluid dynamics are associated with insulin resistance.