Evaluation of neuroactive steroid levels by liquid chromatography-tandem mass spectrometry in central and peripheral nervous system: effect of diabetes.

The nervous system is a target for physiological and protective effects of neuroactive steroids. Consequently, the assessment of their levels in nervous structures under physiological and pathological conditions is a top priority. To this aim, identification and quantification of pregnenolone (PREG), progesterone (PROG), dihydroprogesterone (DHP), tetrahydroprogesterone (THP), testosterone (T), dihydrotestosterone (DHT), 5alpha-androstan-3alpha, 17beta-diol (3alpha-diol), 17alpha- and 17beta-estradiol (17alpha-E and 17beta-E) by liquid chromatography and tandem mass spectrometry (LC-MS/MS) has been set up.

Short acidic peptides isolated from wheat sprout chromatin and involved in the control of cell proliferation. Characterization by infrared spectroscopy and mass spectrometry.

Low molecular weight peptides were isolated from the chromatin of wheat sprouts. Following gel filtration the peptide fraction shows a sharp inhibiting activity on the growth of HeLa cancer cells. Infrared (IR) spectroscopy and mass spectrometry have been utilized to characterize the wheat sprout peptides in an attempt to recognize the peptide sequence involved in the control of cell growth.

Cigarette smoke negatively and dose-dependently affects the biosynthetic pathway of the n-3 polyunsaturated fatty acid series in human mammary epithelial cells.

Maternal smoking during pregnancy has been associated with a reduced content of n-3 long-chain PUFA (LC-PUFA) in breast milk, thereby reducing the intake of key nutrients by the infants. We postulated that the mammary gland is affected by maternal smoking in the process of n-3 LC-PUFA secretion into milk. This prompted us to investigate the effects of cigarette smoke on the synthesis of n-3 LC-PUFA in vitro by using a line of healthy epithelial cells from the human mammary gland, MCF-10A.