Relationship of Total Hemoglobin in Subcutaneous Adipose Tissue with Whole-Body and Visceral Adiposity in Humans

• Main Authors: Miyuki Kuroiwa, Sayuri Fuse, Shiho Amagasa, Ryotaro Kime, Tasuki Endo, Yuko Kurosawa, Takafumi Hamaoka
• Format: Article
• Language: English
• Published: MDPI AG 2019-06-01
• Series: Applied Sciences
• Subjects: near-infrared time-resolved spectroscopy; noninvasive; subcutaneous white adipose tissue; tissue total hemoglobin
• Online Access: https://www.mdpi.com/2076-3417/9/12/2442

High whole-body and visceral adiposity are risk factors that can cause metabolic diseases. We hypothesized that the total hemoglobin concentration (total-Hb) in abdominal subcutaneous adipose tissue (SAT_ab), an indicator of white adipose tissue (WAT) vascularity, correlates negatively with risk factors for developing metabolic diseases, such as whole-body and visceral adiposity. We tested the optical characteristics of abdominal tissue in 140 participants (45 men and 95 women) who were apparently healthy individuals with a median age of 39 years. They also had a median body fat percentage of 25.4%, a visceral fat area of 50.4 cm², and a SAT_ab thickness of 1.05 cm. These tests were conducted using near-infrared time-resolved spectroscopy (NIR_TRS) with a 2-cm optode separation. To distinguish the segments of SAT_ab (Seg_SAT) and the mixture of muscle and SAT_ab (Seg_SAT+Mus), the threshold was analyzed using the slopes of (total-Hb) against the thickness of SAT_ab using the least-squares mean method. According to the results from the logistic regression analysis, the percentage of body fat and visceral fat area remained significant predictors of the (total-Hb) (<i>p</i> = 0.005 and <i>p</i> = 0.043, respectively) in the data for Seg_SAT (no influence from the SAT_ab thickness). We conclude that simple, rapid, and noninvasive NIR_TRS-determined (total-Hb) in WAT could be a useful parameter for evaluating risk factors for metabolic diseases.