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Propolis is an important functional food with numerous biological properties, such as anti-oxidation, anti-inflammation, and immune regulation. However, there are few studies on the effects of propolis on aging-induced muscle atrophy. Here, we aimed to determine whether propolis exerts protective effects against muscle damage caused by d -galactose (D-gal)-induced aging in mice. Propolis was found to ameliorate the morphological alterations generated by D-gal in muscle fibers and considerably increase their cross-sectional area and diameter; ameliorate muscle oxidative stress by boosting Nrf2 and HO-1 expression and Nrf2 nuclear translocation; reduce apoptosis in muscle cells by dramatically increasing Bcl2 expression and decreasing Bax expression; and significantly decreased the level of MAFbx and MuRF1, thus inhibiting skeletal muscle proteolysis. Metabonomic studies showed that propolis can promote protein metabolism and reduce oxidative stress in skeletal muscle. Propolis may reduce prostaglandin and estriol levels by increasing the blood supply to aging skeletal muscles and reducing the lipid peroxide tablets. Propolis may inhibit skeletal muscle cell apoptosis by suppressing isoprenaline metabolism in skeletal muscle, thus playing a role in anti-skeletal muscle aging. Propolis delays skeletal muscle aging by reducing oxidative stress, inhibiting apoptosis, and regulating muscle protein metabolism. [Display omitted] [ABSTRACT FROM AUTHOR]

Allelopathy, the negative effect on plants of chemicals released to the surroundings by a neighboring plant, is an important factor which contributes to the spread of some weeds in plant communities. In this field, Stellera chamaejasme L . (Thymelaeaceae) is one of the most toxic and ecologically-threatening weeds in some of the grasslands of north and west China. Bioassay-guided fractionation of root extracts of this plant led to the isolation of eight flavonoids 1 – 8 , whose structures were elucidated by spectroscopic analysis. All compounds obtained, except 7-methoxylneochaejasmin A ( 4 ) and (+)-epiafzelechin ( 5 ), showed strong phytotoxic activity against Arabidopsis thaliana seedlings. Seedling growth was reduced by neochamaejasmin B ( 1 ), mesoneochamaejasmin A ( 2 ), chamaejasmenin C ( 3 ), genkwanol A ( 6 ), daphnodorin B ( 7 ) and dihydrodaphnodorin B ( 8 ) with IC 50 values of 6.9, 12.1, 43.2, 74.8, 7.1 and 27.3 μg/mL, respectively, and all of these compounds disrupted root development. Endogenous auxin levels at the root tips of the A. thaliana DR5::GUS transgenic line were largely reduced by compounds 1 , 2 and 6 – 8 , and were increased by compound 4 . Moreover, the inhibition rate of A. thaliana auxin transport mutants pin2 and aux1 – 7 by compounds 1 – 8 were all lower than the wild type (Col-0). The influence of these compounds on endogenous auxin distribution is thus proposed as a critical factor for the phytotoxic effect. Compounds 1 , 2 , 4 and 8 were found in soils associated with S. chamaejasme , and these flavonoids also showed phytotoxicity to Clinelymus nutans L., an associated weed of S. chamaejasme . These results indicated that some phytotoxic compounds from roots of S. chamaejasme may be involved in the potential allelopathic behavior of this widespread weed. [ABSTRACT FROM AUTHOR]