Objective: We conducted a double-blind, placebo-controlled, parallel group study to assess the anti-glycation effect of mixed herbal extract (MHE) in individuals with pre-diabetes mellitus. MHE was produced using hot water extraction from Anthemis nobilis (Roman chamomile), Crataegus oxyacantha (hawthorn berry), Houttuynia cordata (dokudami), and Vitis vinifera (grape leaf). We also assessed whether MHE showed favorable effects on one's quality of life (QOL).
Design: The subjects consisted of 26 volunteers (male: 21; female: 5; age: 50.5 ± 8.5 years) with pre- diabetes mellitus (HbA1c: 5.5 - 6.7%). They were divided into two groups, the Test Group (13 subjects, age: 52.8 ± 8.2 years) and the Control Group (12 subjects, age: 49.3 ± 7.8 years). The Test Group was administered 1,200 mg of MHE (solid substance) per day for 8 weeks. The Control Group was administered a placebo.
Results: The inter-group analysis using the Anti-Aging QOL Common Questionnaire (AAQol) showed that the score for the parameters, “muscular pain/stiffness”, “headache”, “easily angered”, “reluctance to talk with others”, “memory lapse”, and “inability to readily make judgments” was significantly improved in the Test Group (p ‹ 0.05). In terms of sugar metabolism, no significant variation was observed in fasting blood glucose, HbA1c, glycoalbumin, and insulin. A significant variation was not observed in the Test Group with regard to 3-deoxyglucosone (3DG), an intermediate of glycation, and N^ε-(carboxymethyl)lysine (CML) and pentosidine, advanced glycation endproducts (AGEs), in blood after 8 weeks. However, in the subjects with HbA1c of equal to or higher than 5.9%, the subclass inter-group analysis showed that the supplementation of MHE significantly inhibited (p ‹ 0.05) an increase of CML in the Test Group, while CML increased in the Control Group. There was no significant variation in the Test Group regarding the oxidative stress markers, 8-hydroxy-2'-deoxyguanosine (8-OHdG) and isoprostane in urine. The skin elasticity index (R2) obtained by using the cutometer started to decrease significantly in the Control Group after 4 weeks (p ‹ 0.05), while the index showed a tendency that the skin elasticity was successfully maintained in the Test Group. There was no adverse event which was associated with the test product.
Conclusion: These results suggest that MHE may improve the symptoms related to QOL as well as inhibit the generation of CML, one of AGEs, in individuals with abnormal sugar metabolism. Furthermore, the 8 weeks supplementation of MHE was considered to be safe.

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Oxidative stress is a high-profile element among the risk factors for aging. Although several stress markers have been proposed for the evaluation of oxidative stress, there remains much room for improvement in testing and evaluation methods. In the Current Concept Session “Oxidative Stress Markers” at the of the most recent research works were presented under the titles “Present Status and New Development of Evaluation of Oxidative Stress Markers,” “Oxidative Modification of Proteins and Its Quantitative Detection,” and “Modification/Degeneration of Proteins and Advanced Glycation Endproducts (AGEs)”.
Several markers are available for evaluation of the oxidative stress status. Methods of detecting oxidatively modified substances as new markers by mass spectrography (MS) have been developed. Oxidative modifications of highly reactive cysteine residues in several target proteins such as tyrosine phosphatase and thioredoxin-related proteins control the functions of relevant molecules, and thereby play an important role in signal transmission. Advanced glycation endproducts (AGEs) gradually accumulate with aging and are involved in the development of diabetic complications, Alzheimer's disease, and arteriosclerosis. Basic studies of the indicators of glycation are also important.
This general article outlines oxidative stress markers with a focus on oxidative modification of proteins and glycation of proteins, both of which have received attention in recent years, and introduces information regarding newly discovered markers for oxidative stress.

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The lipid matrix in the stratum corneum is important to the barrier function of mammalian skin. Ceramides are main components of intercellular lipids in the stratum corneum and play an essential role in skin barrier function. Moreover, recent investigations have demonstrated improvement in skin barrier properties after oral intake of ceramides of plant origin in mice and healthy adults. However, beneficial effects on skin barrier function by oral intake of ceramides other than those of plant origin have not been reported.
It is known that acetic acid bacteria accumulate intracellular ceramides. Therefore, we examined the dietary effect of ceramide-containing acetic acid bacteria on skin barrier function. Studied were 3 groups, each comprised of 20 healthy adults with awareness of dry skin. The control group was given a placebo, the low acetic acid bacteria group [low-dose group] was given 55.6 mg dry acetic acid bacteria containing 400 μg ceramide, and the high acetic acid bacteria group [high-dose group] was administered 111.1 mg dry acetic acid bacteria containing 800 μg ceramide per day for 8 weeks. Transepidermal water loss (TEWL) and stratum corneum hydration (SCH) were measured as indexes of skin barrier function on the cheek, upper inner arm and back of the neck of all study subjects. The most marked effect was on the cheek, the area most exposed. On the cheek, the TEWL value increased significantly on week 4 after starting administration in the control group, but remained at the baseline level in both the low-dose and high-dose groups. In both the low-dose and high-dose groups, TEWL values decreased significantly on week 6. The SCH value increased significantly after 6 weeks administration in the control group, whereas in both the low-dose and high-dose groups the SCH value increased significantly after just 4 weeks of intake. This increase occurred within a shorter period than in the control group. These results suggest that oral intake of ceramide-containing acetic acid bacteria effects to maintain skin barrier function in healthy adults with awareness of dry skin.

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