AUTHOR=Park Ho-Young , Lee Hye-Bin , Lee So-Young , Oh Mi-Jin , Ha Sang Keun , Do Eunju , Lee Hyun Hee L. , Hur Jinyoung , Lee Kwang-Won , Nam Mi-Hyun , Park Myoung Gyu , Kim Yoonsook 

TITLE=Lactococcus lactis KF140 Reduces Dietary Absorption of Nε - (Carboxymethyl)lysine in Rats and Humans via β-Galactosidase Activity

JOURNAL=Frontiers in Nutrition

VOLUME=9

YEAR=2022

URL=https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2022.916262

DOI=10.3389/fnut.2022.916262

ISSN=2296-861X

ABSTRACT=<sec><title>Background and Aims</title><p>Excessive intake of advanced glycation end products (AGEs), which are formed in foods cooked at high temperatures for long periods of time, has negative health effects, such as inflammatory responses and oxidative stress. N<sup>ε</sup>-(Carboxymethyl)lysine (CML) is one of the major dietary AGEs. Given their generally recognized as safe status and probiotic functionalities, lactic acid bacteria may be ideal supplements for blocking intestinal absorption of food toxicants. However, the protective effects of lactic acid bacteria against dietary AGEs have not been fully elucidated.</p></sec><sec><title>Materials and Methods</title><p>We investigated the effect of treatment with <italic>Lactococcus lactis</italic> KF140 (LL-KF140), which was isolated from kimchi, on the levels and toxicokinetics of CML. The CML reduction efficacies of the <italic>Lactococcus lactis</italic> KF140 (LL-KF140), which was isolated from kimchi, were conducted by <italic>in vitro</italic> test for reducing CML concentration of the casein-lactose reaction product (CLRP) and <italic>in vivo</italic> test for reducing serum CML level of LL-KF140 administered rats at 2.0 × 10<sup>8</sup> CFU/kg for14 days. In addition, 12 volunteers consuming LL-KF140 at 2.0 × 10<sup>9</sup> CFU/1.5 g for 26 days were determined blood CML concentration and compared with that before intake a Parmesan cheese.</p></sec><sec><title>Results</title><p>Administration of LL-KF140 reduced serum CML levels and hepatic CML absorption in rats that were fed a CML-enriched product. In a human trial, the intake of LL-KF140 prevented increases in the serum levels of CML and alanine aminotransferase after consumption of a CML-rich cheese. LL-KF140 was determined to presence in feces through metagenome analysis. Furthermore, β-galactosidase, one of the <italic>L. lactis</italic>-produced enzymes, inhibited the absorption of CML and reduced the levels of this AGE, which suggests an indirect inhibitory effect of LL-KF140. This study is the first to demonstrate that an <italic>L. lactis</italic> strain and its related enzyme contribute to the reduction of dietary absorption of CML.</p></sec>