Ingestion of ß-nicotinamide mononucleotide increased blood NAD levels, maintained walking speed, and improved sleep quality in older adults in a double-blind randomized, placebo-controlled study.

The study evaluated how ingestion of nicotinamide mononucleotide (NMN) for 12 weeks by older adults affected blood nicotinamide adenine dinucleotide (NAD +) levels and physical function, particularly walking function. Information concerning sleep, and stress was also collected as secondary endpoints. In this randomized, placebo-controlled, double-blind, parallel-group comparison study, 60 participants were randomly allocated into a placebo group or NMN group. Members of the NMN group consumed 250 mg/day NMN for 12 weeks. Motor function tests, blood NAD metabolite analysis, and questionnaires were conducted at the start of the study and 4 and 12 weeks after intake. This trial was registered at umin.ac.jp/ctr as UMIN000047871 on June 22nd, 2022.At primary outcome, at both 4 weeks and 12 weeks, the NMN and placebo groups had no significant differences in a stepping test. At secondary outcomes, after 12 weeks of NMN intake, the NMN group had a significantly shorter 4-m walking time than the placebo group as well as significantly higher blood levels of NAD + and its metabolites. A significant negative correlation was observed between the change in the 4-m walking time and the change in blood NAD + , N1-methyl-2-pridone-5-carboxamide (2-PY), and N1-methyl-4-pridone-3-carboxamide (4-PY) at 12 weeks. The NMN group had improved sleep quality at 12 weeks relative to the placebo group as evidenced by lower scores for "Daytime dysfunction" and "Global PSQI" on the Pittsburgh Sleep Questionnaire. No adverse effects related to test substance consumption were observed. Together, these results indicate that NMN intake could increase blood NAD + levels, maintain walking speed, and improve sleep quality in older adults. Interventions involving NMN aimed at maintaining walking speed could contribute to extended healthy life expectancy.

Safety evaluation of a heat-treated Bifidobacterium bifidum OLB6378 concentrate.

Several bacterial strains, including probiotic strains, have undergone evaluations for their safety and potential beneficial health effects. Some of these strains have been introduced into various markets, including that for infant products. However, certain probiotic strains have been linked to serious infections in infants, such as septicemia and meningitis. Given this, it is crucial to assess the safety of each probiotic strain, including those of Bifidobacterium, which is a common genus of probiotics. One such strain, Bifidobacterium bifidum OLB6378 (NITE BP-31), referred to as OLB6378 hereafter, has been selected for use in infants. To determine its genotoxicity and general toxicity potential, a heat-treated OLB6378 concentrate was subjected to various tests, including the bacterial reverse mutation test, in vitro chromosome aberration test, in vivo micronucleus test, and single- and 90-day oral gavage toxicity studies in rats. No significant differences were observed compared with negative controls in any of genotoxicity tests. The single-dose toxicity study employed dose levels of 560, 1,693, and 5,092 mg/kg, representing the total solid contents of culture concentrates containing OLB6378 (equivalent to 8.1 × 1011, 2.4 × 1012, and 7.4 × 1012 cells/kg of Bifidobacterium, respectively). In the 90-day toxicity study, dose levels of 280, 853, and 2,546 mg/kg/day were used (equivalent to 4.0 × 1011, 1.2 × 1012, and 3.7 × 1012 cells/kg/day, respectively). Importantly, the heat-treated OLB6378 concentrate did not induce any signs of toxicity in any of the conducted toxicity studies. In conclusion, the heat-treated OLB6378 concentrate exhibited no genotoxicity potential, and the no-observed-adverse-effect level in the 90-day toxicity study was determined to be 2,546 mg/kg/day (equivalent to 3.7 × 1012 cells/kg/day). This suggests that heat-treated OLB6378 can be safely utilized as a food source.