Yin and Yang of ginseng pharmacology： ginsenosides vs gintonin

Ginseng, the root of Panaxginseng, has been used in traditional Chinese medicine as a tonic herb that provides many beneficial effects. Pharmacologic studies in the last decades have shown that ginsenosides （ginseng saponins） are primarily responsible for the actions of ginseng. However, the effects of ginseng are not fully explained by ginsenosides. Recently, another class of active ingredients called gintonin was identified. Gintonin is a complex of glycosylated ginseng proteins containing lysophosphatidic acids （LPAs） that are the intracellular lipid mitogenic mediator. Gintonin specifically and potently activates the G protein-coupled receptors （GPCRs） for LPA. Thus, the actions of ginseng are now also linked to LPA and its GPCRs. This linkage opens new dimensions for ginseng pharmacology and LPA therapeutics. In the present review, we evaluate the pharmacology of ginseng with the traditional viewpoint of Yin and Yang components. Furthermore, we will compare ginsenoside and gintonin based on the modern view of molecular pharmacology in terms of ion channels and GPCRs.     

An ultrastructural study of alimentary tract development in the cercariae of Diplostomum pseudospathaceum (Digenea: Diplostomidae)

Morphogenesis of the alimentary canal in developing Diplostomum pseudospathaceum cercariae has been studied using electron microscopy. The foregut primordium appears in early cercariae as a cellular cord. Later, the lumen develops within the foregut primordium, and its cells give rise to the cellular epithelium, limiting this lumen. During subsequent development, the lateral plasma membranes, separating the cells, disappear from the primary foregut epithelium as do nuclei and most of cellular organelles. These events seem to progress in several steps, and eventually, the foregut lining becomes the thin anucleate syncytial layer. In late cercariae, this layer becomes connected with nucleated cytons, producing secretory inclusions. Each of two caecal branches appears to arise from a row of large cuboid cells. The primordial gastrodermal cells are involved in synthetic and secretory activity and give rise to numerous secretory inclusions. These inclusions release their contents into the cavities which develop between adjacent primordial caecal cells. The intercellular cavities gradually increase in size and fuse to eventually form a single caecal lumen. In mature cercariae, the large caecal lumen packed with electron-dense secretory material is limited by a thin cellular gastrodermis, displaying no secretory features.     

Increase in sphingolipid catabolic enzyme activity during aging

Aim： To understand the contribution of sphingolipid metabolism and its metabolites to development and aging. Methods： A systemic analysis on the changes in activity of sphingolipid metabolic enzymes in kidney, liver and brain tissues during development and aging was conducted. The study was conducted using tissues from 1-day-old to 720-day-old rats. Results： Catabolic enzyme activities as well as the level of sphingomyelinase （SMase） and ceramidase （CDase） were higher than that of anabolic enzyme activities, sphingomyelin synthase and ceramide synthase. This suggested an accumulation of ceramide and sphingosine during development and aging. The liver showed the highest neutral-SMase activity among the tested enzymes while the kidney and brain exhibited higher neutral-SMase and ceramidase activities, indicating a high production of ceramide in liver and ceramide/sphingosine in the kidney and brain. The activities of sphingolipid metabolic enzymes were significantly elevated in all tested tissues during development and aging, although the onset of significant increase in activity varied on the tissue and enzyme type. During aging, 18 out of 21 enzyme activities were further increased on day 720 compared to day 180. Conclusion： Differential increases in sphingolipid metabolic enzyme activities suggest that sphingolipids including ceramide and sphingosine might play important and dynamic roles in proliferation, differentiation and apoptosis during development and aging.