Genome-wide mining of gpx gene family provides new insights into cadmium stress responses in common carp (Cyprinus carpio).

Glutathione peroxidase (Gpx) is an important member of antioxidant enzymes, which can play a vital role in metabolizing reactive oxygen species (ROS) and in maintaining cell homeostasis. In order to study the evolutionary dynamics of gpx gene family in allotetraploid fish species, we identified a total of 14 gpx genes in common carp Cyprinus carpio, while 9 gpx genes were discovered in the diploid progenitor-like species Poropuntius huangchuchieni. Comparative genomic analysis and phylogenetic analysis revealed that the common carp gpx genes had significant expansion and were divided into five distinct subclades. Exon-intron distribution patterns and conserved motif analysis revealed highly conserved evolutionary patterns. Transcript profiles suggested that different gpx genes had specific patterns of regulation during early embryonic development. In adult tissues, gpx genes had a relatively broad expression distribution, most of which were highly expressed in the gills, intestines, and gonads. RT-qPCR studies showed that most gpx genes were downregulated during the initial cd2+ treatment stage. Dietary supplementation of Bacillus coagulans at different concentrations (Group 2 of 1.0 × 107 cfu/g, Group 3 of 1.0 × 108 cfu/g, and Group 4 of 1.0 × 109 cfu/g) induced different regulatory responses of gpx subclades. This result suggested that the appropriate concentration of B. coagulans can improve gpx gene expression when exposed to heavy metal cadmium treatment, which may play a vital role in the resistance to oxidative stress and immune responses. This study has expanded our understanding of the functional evolution of the gpx gene family in common carp.

Cysestermerol A, a rare stilbene sestermer with significant hypoglycemic activities from Cynodon dactylon.

Cysestermerol A (1), a rare and new stilbene sestermer, was isolated from the whole herb of Cynodon dactylon. The planar and relative structures of 1 were elucidated based on HRESIMS, one- and two-dimensional NMR analyses, and its absolute configuration was further established by electronic circular dichroism calculations. Compound 1 obviously increased the glucose consumption in HepG2 cells equivalent to the positive control rosiglitazone and markedly inhibited the activity of α-glucosidase in vitro.

Two new stilbene trimers from Cynodon dactylon.

Many naturally occurring oligostilbenes have drawn considerable attention because of their intricate structures and diverse bioactivities. Two new stilbene trimers, cystibenetrimerol A (1) and cystibenetrimerol B (2) were isolated from the dried grass of Cynodon dactylon (L.) Pers. The planar structures and stereo configurations of them were elucidated by spectroscopic and spectrometric methods. The isolation and structures elucidation of two new stilbene trimers suggested the ordinary grass belonging to the family Poaceae may be a rich source of stilbene oligomers.