Study of Therapeutic Effects of Losartan for Sarcopenia Based on the F344xBN Rat Aging Model.

BACKGROUND/AIM: Sarcopenia is an age-related disease in which muscle mass and strength are markedly reduced. There are few effective treatments, but the angiotensin II receptor antagonist losartan has been reported to be effective. Our aim was to evaluate the therapeutic effectiveness of losartan for sarcopenia and explore the underlying mechanisms. MATERIALS AND METHODS: We investigated body weight, muscle mass (gastrocnemius, soleus, peroneus longus, and tibialis anterior muscles), and serum markers in an aged rat model population divided into four treatment groups: Control, exercise, losartan, and exercise plus losartan. The rats were sacrificed at 6, 12, or 18 months after the start of the experiment and autopsies were performed. RESULTS: Compared with the control group, average muscle mass and weight increased in the two groups treated with losartan. AKT serine/threonine kinase (AKT) and extracellular signal-regulated kinase (ERK) muscle growth factors increased in the peroneus longus. mechanistic target of rapamycin kinase (mTOR) increased in tibialis anterior, peroneus longus, and soleus. CONCLUSION: Losartan treatment slowed muscle degeneration and activated the PI3K-AKT-mTOR and ERK/mitogen-activated protein kinase signalling pathways required for production of muscle growth factors when combined with exercise.

Serum carcinoembryonic antigen is associated with metabolic syndrome in female Korean non-smokers.

BACKGROUND: Carcinoembryonic antigen (CEA), a serological marker of malignant tumors, demonstrates a modest increase under nonmalignant conditions and the pro-inflammatory features of CEA suggest that CEA may be related to insulin resistance and metabolic syndrome. METHODS: A total of 7075 female Korean non-smokers who underwent health check-ups were analyzed in the present study. The interquartile cutoff values for serum CEA concentrations were 0.39, 0.84, and 1.40 ng/ml. RESULTS: The prevalence of metabolic syndrome increased significantly with the increasing CEA quartiles, and the age-adjusted mean CEA concentration increased consistently with each additional component of metabolic syndrome. Logistic regression analysis adjusted for age, alcohol intake, exercise, body mass index, total cholesterol, WBC count, and hsCRP showed that the third and fourth CEA quartiles were associated with metabolic syndrome with odds ratios of 1.29 (95% CI 1.07 to 1.63 P<0.001) and 1.39 (95% CI 1.10 to 1.66, P<0.001), respectively. CONCLUSION: In female Korean non-smokers, serum CEA was independently associated with metabolic syndrome. The pathophysiologic and clinical significance of these findings requires further investigation.

Enzymatic synthesis and characterization of hydroquinone galactoside using Kluyveromyces lactis lactase.

Hydroquinone galactoside (HQ-Gal) as a potential skin whitening agent was synthesized by the reaction of lactase (beta-galactosidase) from Kluyveromyces lactis, Aspergillus oryzae, Bacillus circulans, and Thermus sp. with lactose as a donor and HQ as an acceptor. Among these lactases, the acceptor reaction involving HQ and lactose with K. lactis lactase showed a higher conversion ratio to HQ-Gal (60.27%). HQ-Gal was purified using butanol partitioning and silica gel column chromatography. The structure of the purified HQ-Gal was determined by nuclear magnetic resonance, and the ionic product was observed at m/z 295 (C12H16O7Na)+ using matrix assisted laser desorption ionization time-of-flight mass spectrometry. HQ-Gal was identified as 4-hydroxyphenyl-beta-d-galactopyranoside. The optimum conditions for HQ-Gal synthesis by K. lactis determined using response surface methodology were 50 mM HQ, 60 mM lactose, and 20 U mL(-1) lactase. These conditions produced a yield of 2.01 g L(-1) HQ-Gal. The half maximal inhibitory concentration (IC50) of diphenylpicrylhydrazyl scavenging activity was 3.31 mM, indicating a similar antioxidant activity compared to beta-arbutin (IC50=3.95 mM). The Ki value of HQ-Gal (0.75 mM) against tyrosinase was smaller than that of beta-arbutin (Ki=1.97 mM), indicating its superiority as an inhibitor. HQ-Gal inhibited (23%) melanin synthesis without being significantly toxic to the cells, while beta-arbutin exhibited only 8% reduction of melanin synthesis in B16 melanoma cells compared with the control. These results indicate that HQ-Gal may be a suitable functional component in the cosmetics industry.

Characterization of nanoporous structures of polyphenylene oxide derived carbon membranes by means of 129Xe NMR.

The 129Xe NMR spectroscopy has become a powerful technique of materials characterization because the xenon atom has a very large polarizability. It is well known that the signal of xenon sorbed in porous media is sensitively affected by the surrounding environments such as the chemistry of material surface. In this study, the pore properties of nanoporous PPO (polyphenylene oxide) derived carbon membranes were characterized by means of the variable temperature (VT)-hyperpolarized Xe NMR. The Xe NMR results showed good agreements with the adsorption results of CO2 for the PPO derived nanoporous carbon membranes. It was clearly shown that the 129Xe NMR could be used as one of the promising characterization methods of nanoporous materials with low surface area and small pore volume.

Enzymatic synthesis and characterization of arbutin glucosides using glucansucrase from Leuconostoc mesenteroides B-1299CB.

Two arbutin glucosides were synthesized via the acceptor reaction of a glucansucrase from Leuconostoc mesenteroides B-1299CB with arbutin and sucrose. The glucosides were purified by Bio-gel P-2 column chromatography and high-performance liquid chromatography, and the structures were elucidated as 4-hydroxyphenyl beta-isomaltoside (arbutin-G1), 4-hydroxyphenyl beta-isomaltotrioside (arbutin-G2), according to the results of (1)H, (13)C, heteronuclear single-quantum coherence, (1)H-(1)H COSY, and heteronuclear multiple-bond correlation analyses. Arbutin glucoside (4-hydroxyphenyl beta-isomaltoside) exhibited slower effects on 1,1-diphenyl-2-picrylhydrazyl radical scavenging and similar effects on tyrosinase inhibition, and increased inhibitory effect on matrix metalloproteinase-1 production induced by UVB than arbutin.