An exploratory clinical trial on the effects of mixed herb extract on the inhibition of glycative stress

抄録

Objective: Accumulation of advanced glycation end products (AGEs) produced by glycative stress promotes the progression of age-related diseases. We conducted an exploratory study in humans using mixed herb extracts that have both enhancing action of oxidized protein hydrolase (OPH) activity in the body and AGEs crosslink cleaving activity. Method: The subjects were 24 women 40 years or older and less than 65 years of age with high levels of skin AGEs deposits. Three kinds of the following herbs were extracted in hot water: fenugreek (Trigonella foenum-graecum) seeds, fennel (Foeniculum vulgare) seeds, and hibiscus (Hibiscus sabdariffa) calyxes and bracts. Solid contents of the extracts and dextrin were mixed in a ratio of 6:4 to produce mixed herb extract (MHE) powder (brand name: Satonaceil). The test food was a food product in a capsule form. The daily intake of the test food was 100 mg/day for the L group (n = 12) and 300 mg/day for the H group (n = 12) as MHE. The ingestion period was 12 weeks. Before ingestion, and at 6 and 12 weeks post-ingestion, physical examination, blood test, urine test, skin-related tests, and a questionnaire were performed. Note that this study was conducted upon approval by an ethics review committee. (UMIN Clinical Trial ID: UMIN000025986). [Results] Because two subjects violated the exclusion criteria after the start of the study, 11 subjects each were to be analyzed in the L group and the H group. Significant reductions were observed in the levels of pentosidine and fasting blood glucose in both groups at 12 weeks post-ingestion compared to those pre-ingestion. Significant reductions were also observed in the score of wrinkle (on the left and right) measured with VISIA in the L group and HOMA-IR in the H group. In addition, there was a tendency for 3-deoxyglucosone (3DG) to decrease in the L group and for carboxymethyl lysine (Nε-(carboxymethyl)lysine: CML) to decrease in the H group. Further, significant reductions in several liver-function-related indices were observed. In the safety evaluation, no adverse events or abnormal variations in laboratory parameters attributable to the test food were observed. [Conclusion] Effects of MHE ingestion on the reduction of AGEs seen in basic studies can be expected in humans, as demonstrated by the significant decrease or tendency to decrease of glycative-stress-related parameters. Furthermore, ingestion of this MHE was confirmed to be safe.