Effect of elicitors, precursors and metabolic inhibitors on paclitaxel production by Taxus cuspidata cell culture

In this study, using Taxus cuspidata as a raw material, we obtained stable high-yielding cell lines by subculturing and quantified paclitaxel content using ultra- sonic extraction combined with TLC-UV spectrophotom- etry. In single factor and multiple factors tests to optimize design and study the effects of elicitors, precursors, and metabolic inhibitors on paclitaxel production by Taxus cuspidata cells, paclitaxel production reached 4.32 mg/L when 100 μmol/L methyl jasmonate, 20 mg/L salicylic acid, 400 mg/L phenylalanine and 2 mg/L gibberellin （GA3） were added to the culture medium of suspension cells. When adding metabolic adjustment factors on the 7th day of culture, extra- and intracellular paclitaxel production was the highest at 4.855 mg/L, paclitaxel release rate was 10.48 %, fresh mass and paclitaxel production of cell increased, respectively, by 6.08 and 11.57 %. By controlling the anabolism of paclitaxel, paclitaxel yield was significantly improved.

Silicon Affects Transcellular and Apoplastic Uptake of Some Nutrients in Plants

The positive effects of silicon(Si) on growth of plants have been well documented;however,the impact of Si on plant nutrient uptake remains unclear.The growth,nutrient content and uptake of wheat(Triticum aestivum L.),canola(Brassica napus L.) and cotton(Gossypium hirsutum L.) plants were evaluated with or without application of 1.5 mmol L^(-1) Si.Application of Si increased dry weights by 8%,30%and 30%and relative growth rate(RGR) by 10%,13%and 17%in the cotton,canola and wheat plants,respectively.The plant relative water content(RWC) was also increased,but the plant transpiration was decreased by Si application.The uptake and content of Ca^(2+) were 19%and 21%lower in the cotton and wheat plants with Si than those without Si,respectively;however,Si application increased both K^+ and Fe uptake and contents in all plant species.Silicon application reduced B uptake and content only in cotton and increased P and Zn^(2+) contents in all three plant species.The decrease in Ca^(2+) uptake by Si application was sustained even in the presence of metabolic inhibitors 2,4-dinitrophenol and sodium cyanide.Uptake of Ca^(2+) by Si application was enhanced or did not change when plant shoots were saturated with water vapor or their roots were exposed to low temperature.Thus,Si application increased the uptake of transcellularly transported elements like K^+,P,Zn^(2+) and Fe.In contrast,Ca2+ uptake which occurred via both apoplastic and transcellular pathways was decreased by Si application,possibly through reduction of apoplastic uptake.More efficient nutrient uptake might be another promoting effect of Si on plant growth.

Review of pharmacological inhibition of thyroid cancer metabolism

Thyroid cancer(TC)is the most common malignancy of the endocrine system and has been rapidly increasing in incidence over the past few decades.Aggressive TCs metastasize quickly and often levy poor prognoses,as they are frequently resistant to first-line treatment options.Patients diagnosed with aggressive,dedifferentiated TC have a prognosis of under a year with the most current treatment modalities.Like many cancers,TCs also exhibit altered cell metabolism,which enhances the cell’s ability to generate energy,protect against reactive oxygen species,and synthesize macromolecules such as lipids,proteins,and nucleotides for proliferation.Genetic and enzyme profiling of TC tissues and cell lines have uncovered several dysregulated metabolic pathways such as glycolysis,the pentose phosphate pathway,glutamine metabolism,and pyrimidine synthesis.These aberrations are most often due to overexpression of rate-limiting enzymes or metabolite transporters.Metabolic pathways pose attractive therapeutic targets in aggressive TC and may serve to work in tandem with standard therapeutics such as kinase inhibitors depending on the genetic,metabolic,and signaling backgrounds of individual tumors.Further studies are needed to clearly delineate altered metabolic targets across TC subtypes for implementing therapeutic metabolic inhibitors that have shown success in other aggressive tumors.