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Journal Highlights

In vitro propagation of North American ginseng (Panax quinquefolius L.)

Esther E. Uchendu
Dan W. Brown
Gopinadhan Paliyath Praveen K. Saxena

North American ginseng (Panax quinquefolius L.) is a slow growing medicinal plant which has unique multiple uses particularly in the natural health product industry. Addition of antioxidants and other chemically active compounds into the culture medium was explored to improve in vitro plant growth. We used liquid-based medium supplemented with chemical additives and plant growth regulators, in a simple bioreactor system to improve plant production through single node segments. To understand the role of phenolics on ginseng growth, we quantified phenolic production by in vitro plants and examined effects of chemical additives such as activated charcoal, melatonin, polyvinylpolypyrrolidone, and ascorbic acid on plant growth. Phenolic production increased significantly during in vitro culture with a negative impact on the explant growth and proliferation. Activated charcoal significantly reduced total phenolic content and was the most effective treatment for increasing shoot proliferation. It was observed that shoot production increased as the phenolic content of the cultures decreased. The most effective treatment for ginseng development from cultured nodal explants in the bioreactor was 2.5 mg/l kinetin, 0.5 mg/ l NAA, and 50 mg/l AC in liquid culture medium. All of the resulting plants looked normal, and 93% of the rooted plants were established in the greenhouse. Esther E. Uchendu, Gopinadhan Paliyath, Dan C. W. Brown, and Praveen K. Saxena. In vitro propagation of North American ginseng (Panax quinquefolius L.). In Vitro Cellular & Developmental Biology-Plant,
DOI 10.1007/s11627-011-9379-y.


Induction of oligodendrocyte differentiation from adult human fibroblast-derived induced pluripotent stem cells

Teruyuki Nagamune
Jun Miyake
Shin-ichiro Ogawa Yasuhito Tokumoto

Induced pluripotent stem cells (iPSCs) prepared from somatic cells might become a novel tool in regenerative medicine and drug discovery. In vitro directed-differentiation of specific cell types from human iPSCs is the indispensable needs for such purposes. Oligodendrocytes, the myelinating cells in central nervous system, are one of the hardest targets for in vitro directed-differentiation. Even using human neural stem cells that are prepared from fetal brain, it is difficult to induce oligodendrocytes in vitro. In this study, our team in the Graduate school of Engineering, the University of Tokyo, attempted to induce oligodendrocytes from adult human fibroblast-derived iPSCs. These cells were gifts from Shinya Yamanaka in Kyoto University. We treated the cells with in vitro oligodendrocyte directed-differentiation protocols that were optimized for human embryonic stem cells. Although the efficiency was low (less than 0.01%), we had succeeded in the induction of oligodendrocyte differnetiation from adult human iPSCs in vitro.  Shin-ichiro Ogawa, Yasuhito Tokumoto, Jun Miyake, and Teruyuki Nagamune.  Induction of oligodendrocyte differentiation from adult human fibroblast-derived induced pluripotent stem cells.  In Vitro Cellular and Developmental Biology-Animal, 47:464-469, 2011.



First author Dr. Chengliu Jin (left), lab group leader Dr. Wallace McKeehan (center)
and contributing graduate student Chaofeng Yang (standing)
working with tumor-bearing animals prior to cell culture.

FGFR3-expressing smooth muscle-like stromal cells differentiate in response to FGFR2IIIb-expressing prostate tumor cells and delay tumor progression

Precise communication between prostate epithelial cells and differentiated surrounding stromal cells is essential for normal tissue homeostasis.  Precise two way communication between prostate stroma and epithelium is mediated in part by compartmentation of signal FGF and FGF receptor within the FGF tyrosine kinase signal transduction system.  Prostate cancer arises from prostate epithelial cells that escape the growth-controlling features of the microenvironment including stromal cell signals.  In this report, the McKeehan research group using a well-defined in vivo-in vitro transplantable prostate tumor model that consists of both stroma and epithelium showed that it is specifically the stromal cell type with smooth muscle cell properties that holds prostate tumor cells in check.  Apparently it does this by retention of capability to differentiate in response to FGF signals from the epithelial cells themselves.  This differentiation in turn restricts tumor epithelial cell growth and delays progression to malignancy of the overall tumor.  The authors study demonstrated the precise two-way mutual communication within the FGF signaling system that occurs between stroma and epithelial cells and suggests a way that more malignant epithelial cells escape control by the stroma.   Chengliu Jin, Chaofeng Yang, Xiaochung Wu, Fen Wang, and Wallace L. McKeehanFGFR3-expressing smooth muscle-like stromal cells differentiate in response to FGFR2IIIb-expressing prostate tumor cells and delay tumor progression.  In Vitro Cellular and Developmental Biology-Animal, 47:500-505, 2011.