A Novel Nicotinamide Adenine Dinucleotide Correction Method for Intracellular Ca<sup>2+</sup> Measurement with Fura-2-Analog in Live Cells

We introduce a new class of semisynthetic fluorescent biosensors for the quantification of free nicotinamide adenine dinucleotide (NAD+) and ratios of reduced to oxidized nicotinamide adenine dinucleotide phosphate (NADPH/NADP+) in live cells. Sensing is based on controlling the spatial proximity of two synthetic fluorophores by binding of NAD(P) to the protein component of the sensor. The sensors possess a large dynamic range, can be excited at long wavelengths, are pH-insensitive, have tunable response range and can be localized in different organelles. Ratios of free NADPH/NADP+ are found to be higher in mitochondria compared to those found in the nucleus and the cytosol. By recording free NADPH/NADP+ ratios in response to changes in environmental conditions, we observe how cells can react to such changes by adapting metabolic fluxes. Finally, we demonstrate how a comparison of the effect of drugs on cellular NAD(P) levels can be used to probe mechanisms of action.

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Differentiation of apoptosis from necrosis by dynamic changes of reduced nicotinamide adenine dinucleotide fluorescence lifetime in live cells

Journal of Biomedical Optics ◽

10.1117/1.2975831 ◽

2008 ◽

Vol 13 (5) ◽

pp. 054011 ◽

Cited By ~ 67

Author(s):

Hsing-Wen Wang ◽

Vladimir Gukassyan ◽

Chien-Tsun Chen ◽

Yau-Huei Wei ◽

Han-Wen Guo ◽

...

Keyword(s):

Fluorescence Lifetime ◽

Nicotinamide Adenine Dinucleotide ◽

Nicotinamide Adenine ◽

Live Cells ◽

Dynamic Changes ◽

Reduced Nicotinamide Adenine Dinucleotide

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Effect of Niacin on Mitochondria of Allium Cepa Root Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100060404 ◽

1967 ◽

Vol 25 ◽

pp. 78-79

Author(s):

M. Arif Hayat

Keyword(s):

Nicotinamide Adenine Dinucleotide ◽

Hydrogen Transfer ◽

Nicotinamide Adenine Dinucleotide Phosphate ◽

Nicotinamide Adenine ◽

Root Tips ◽

Root Cells ◽

Transfer Processes ◽

Standard Procedures ◽

A Cell ◽

Critical Interest

Although it is recognized that niacin (pyridine-3-carboxylic acid), incorporated as the amide in nicotinamide adenine dinucleotide (NAD) or in nicotinamide adenine dinucleotide phosphate (NADP), is a cofactor in hydrogen transfer in numerous enzyme reactions in all organisms studied, virtually no information is available on the effect of this vitamin on a cell at the submicroscopic level. Since mitochondria act as sites for many hydrogen transfer processes, the possible response of mitochondria to niacin treatment is, therefore, of critical interest.Onion bulbs were placed on vials filled with double distilled water in the dark at 25°C. After two days the bulbs and newly developed root system were transferred to vials containing 0.1% niacin. Root tips were collected at ¼, ½, 1, 2, 4, and 8 hr. intervals after treatment. The tissues were fixed in glutaraldehyde-OsO4 as well as in 2% KMnO4 according to standard procedures. In both cases, the tissues were dehydrated in an acetone series and embedded in Reynolds' lead citrate for 3-10 minutes.

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