@article {Yamakadoe000661, author = {Shinnosuke Yamakado and Hiroki Cho and Mikio Inada and Mika Morikawa and Yong-Huang Jiang and Kenji Saito and Kazunari Nakaishi and Satoshi Watabe and Hitomi Takagi and Mugiho Kaneda and Akira Nakatsuma and Masaki Ninomiya and Hitomi Imachi and Takeshi Arai and Takuo Yoshimoto and Koji Murao and Jyun-Hao Chang and Shih-Min Chen and Yi-Chen Shih and Min-Jing Zeng and Liang-Yin Ke and Chu-Huang Chen and Teruki Yoshimura and Toshiaki Miura and Etsuro Ito}, title = {Urinary adiponectin as a new diagnostic index for chronic kidney disease due to diabetic nephropathy}, volume = {7}, number = {1}, elocation-id = {e000661}, year = {2019}, doi = {10.1136/bmjdrc-2019-000661}, publisher = {BMJ Specialist Journals}, abstract = {Objective The chronic kidney disease (CKD) is widely diagnosed on the basis of albuminuria and the glomerular filtration rate. A more precise diagnosis of CKD, however, requires the assessment of other factors. Urinary adiponectin recently attracted attention for CKD assessment, but evaluation is difficult due to the very low concentration of urinary adiponectin in normal subjects.Research design and methods We developed an ultrasensitive ELISA coupled with thionicotinamide-adenine dinucleotide cycling to detect trace amounts of proteins, which allows us to measure urinary adiponectin at the subattomole level. We measured urinary adiponectin levels in 59 patients with diabetes mellitus (DM) and 24 subjects without DM (normal) to test our hypothesis that urinary adiponectin levels increase with progression of CKD due to DM.Results The urinary adiponectin levels were 14.88{\textpm}3.16 (ng/mg creatinine, mean{\textpm}SEM) for patients with DM, and 3.06{\textpm}0.33 (ng/mg creatinine) for normal subjects. The threshold between them was 4.0 ng/mg creatinine. The urinary adiponectin levels increased with an increase in the CKD risk. Furthermore, urinary adiponectin mainly formed a medium-molecular weight multimer (a hexamer) in patients with DM, whereas it formed only a low-molecular weight multimer (a trimer) in normal subjects. That is, the increase in urinary adiponectin in patients with DM led to the emergence of a medium-molecular weight form in urine.Conclusions Our new assay showed that urinary adiponectin could be a new diagnostic index for CKD. This assay is a non-invasive test using only urine, thus reducing the patient burden.}, URL = {https://drc.bmj.com/content/7/1/e000661}, eprint = {https://drc.bmj.com/content/7/1/e000661.full.pdf}, journal = {BMJ Open Diabetes Research and Care} }