Plasma amino acid profiles are associated with insulin, C-peptide and adiponectin levels in type 2 diabetic patients

Abstract

Objectives:Plasma-free amino acid (PFAA) profiles have been associated with a future risk of developing diabetes or cardiovascular disease in nondiabetic subjects. These PFAA alterations might predominantly result from the metabolic shift caused by insulin resistance and visceral fat deposition. The variety of PFAA profiles within diabetic subjects is not well researched. In this study, we focused on type 2 diabetic subjects and examined the association between PFAA profiles and insulin- and glucose-related variables.Methods:Fifty-one Japanese subjects diagnosed with type 2 diabetes were recruited from an outpatient clinic. The plasma concentrations of 21 amino acids; glucose-related markers including glucose, hemoglobin A1c (HbA1c), glycoalbumin and 1,5-anhydroglucitol; insulin-related markers including insulin, C-peptide, and the homeostasis model assessment of insulin resistance; and adipocytokines including adiponectin and leptin were determined. The association of PFAA and other metabolic profiles were analyzed, and stratified analyses of the PFAAs and clinical characteristics were performed according to the fasting plasma insulin and HbA1c levels. In addition, the PFAA indices that correlate to visceral fat obesity were evaluated.Results:Although strong correlations between PFAAs and glucose-related markers were not observed, several amino acids (branched-chain amino acids, tryptophan, alanine, tyrosine, glutamate and proline) and PFAA indices that evaluate visceral obesity were highly correlated with insulin-related markers and adiponectin (P<0.001). In the group of diabetic patients with hyperinsulinemia, the amino acid levels were significantly increased, which generally demonstrated good concordance with insulin-related markers and adiponectin levels.Conclusions:The PFAA profiles in diabetic patients were strongly associated with hyperinsulinemia and hypoadiponectinemia, which might become risk evaluation factors for the development of cardiovascular diseases.

Plasma amino acid levels are elevated in young, healthy low birth weight men exposed to short-term high-fat overfeeding

“…In similarity to our study, higher plasma amino acid levels have repeatedly been reported to associate with insulin resistance (Newgard et al 2009;Tai et al 2010;Wurtz et al 2012a;Nakamura et al 2014;Seibert et al 2015;Pedersen et al 2016). To this end, plasma amino acid levels, in particular of the branched chain amino acids valine, leucine, and isoleucine, aromatic amino acids tyrosine and phenylalanine, and alanine, are predictive of development of type 2 diabetes even several years before its onset (Wang et al 2011;Wurtz et al 2012bWurtz et al , 2013Yamakado et al 2015).…”

CE‐MS‐based serum fingerprinting to track evolution of type 2 diabetes mellitus

“…The only AA, which change with T2DM evolution was found characteristic only for OB group was lysine. Based on literature data T2DM has minor effect on lysine metabolism , however it was found to be correlated with plasma glucose level . Also in our study, the change of lysine is minor, and observed only in obese subjects.…”

Plasma amino acid profiles in healthy East Asian subpopulations living in Japan

“…Our previous study also found that sex is a more influential factor for PFAA profiles than age or BMI (Yamamoto et al, 2015). In addition, reports have indicated that PFAA levels are strongly correlated with visceral fat area and insulin‐related parameters but not with subcutaneous fat area (Nakamura et al, 2014; Yamakado et al, 2012). Furthermore, the ingestion of a low‐protein diet leads to decreased PFAA levels (Fujita et al, 1978).…”