TY - JOUR T1 - Quantification of Neurotransmitters from Intact and Regenerating Planarians Using UHPLC-MS/SRM Method. JF - Methods Mol Biol Y1 - 2018 A1 - Rangiah, Kannan A1 - Palakodeti, Dasaradhi KW - Animals KW - Chromatography, High Pressure Liquid KW - Neurotransmitter Agents KW - Planarians KW - Regeneration KW - Stem Cells KW - Tandem Mass Spectrometry AB -

Freshwater planarian species S. mediterranea is an emerging stem cell model because of its capability of regenerating large portions of missing body parts. It is one of the best model systems available to address the basic biological mechanisms in the regeneration processes. Absolute quantification of metabolites from planarians is imperative to understand their role in the regeneration processes. Here we describe a stable isotope dilution ultrahigh performance liquid chromatography/mass spectrometry/selected reaction monitoring (UHPLC-MS/SRM) assay for a sensitive and quantitative assessment of neurotransmitters (NTs) in planaria. We used this method for the simultaneous quantification of 16 NTs from both intact and regenerating planarians.

VL - 1774 ER - TY - JOUR T1 - A quantitative metabolomics peek into planarian regeneration. JF - Analyst Y1 - 2015 A1 - Natarajan, Nivedita A1 - Ramakrishnan, Padma A1 - Lakshmanan, Vairavan A1 - Palakodeti, Dasaradhi A1 - Rangiah, Kannan KW - Animals KW - Calibration KW - Chromatography, High Pressure Liquid KW - Limit of Detection KW - Metabolomics KW - Planarians KW - Reference Standards KW - Regeneration KW - Reproduction, Asexual KW - Species Specificity KW - Tandem Mass Spectrometry AB -

The fresh water planarian species Schmidtea mediterranea is an emerging stem cell model because of its capability to regenerate a whole animal from a small piece of tissue. It is one of the best model systems to address the basic mechanisms essential for regeneration. Here, we are interested in studying the roles of various amines, thiols and nucleotides in planarian regeneration, stem cell function and growth. We developed mass spectrometry based quantitative methods and validated the differential enrichment of 35 amines, 7 thiol metabolites and 4 nucleotides from both intact and regenerating planarians. Among the amines, alanine in sexual and asparagine in asexual are the highest (>1000 ng/mg) in the intact planarians. The levels of thiols such as cysteine and GSH are 651 and 1107 ng mg(-1) in planarians. Among the nucleotides, the level of cGMP is the lowest (0.03 ng mg(-1)) and the level of AMP is the highest (187 ng mg(-1)) in both of the planarian strains. We also noticed increasing levels of amines in both anterior and posterior regenerating planarians. The blastema from day 3 regenerating planarians also showed higher amounts of many amines. Interestingly, the thiol (cysteine and GSH) levels are well maintained during planarian regeneration. This suggests an inherent and effective mechanism to control induced oxidative stress because of the robust regeneration and stem cell proliferation. Like in intact planarians, the level of cGMP is also very low in regenerating planarians. Surprisingly, the levels of amines and thiols in head regenerating blastemas are ∼3 times higher compared to those for tail regenerating blastemas. Thus our results strongly indicate the potential roles of amines, thiols and nucleotides in planarian regeneration.

VL - 140 IS - 10 ER -