Abstract: A method of increasing expression of a molecular chaperon by a cell and/or enhancing the activity of a molecular chaperon in cells is provided. The method comprises treating a cell that is exposed to a physiological stress which induces expression of a molecular chaperon by the cell with an effective amount of a certain hydroxylamine derivative to increase the stress. Alternatively, an hydroxylamine derivative can be administrated to a cell before it is exposed to a physiological stress which induces expression of a molecular chaperon by the cell. Preferably, the cell to which an hydroxylamine derivative is administered is an eukaryotic cell. The hydroxylamine derivative corresponds to the formulae (I) or (II). The invention also provides novel hydroxylamine derivatives falling within the scope of the formulae (I) and (II) as well as pharmaceutical and/or cosmetical compositions comprising the said compounds.

Abstract: A method of increasing expression of a molecular chaperon by a cell and/or enhancing the activity of a molecular chaperon in cells is provided. The method comprises treating a cell that is exposed to a physiological stress which induces expression of a molecular chaperon by the cell with an effective amount of a certain hydroxylamine derivative to increase the stress. Alternatively, an hydroxylamine derivative can be administrated to a cell before it is exposed to a physiological stress which induces expression of a molecular chaperon by the cell. Preferably, the cell to which an hydroxylamine derivative is administered is an eukaryotic cell. The hydroxylamine derivative corresponds to the formulae (I) or (II).

Abstract: A method of increasing expression of a molecular chaperon by a cell and/or enhancing the activity of a molecular chaperon in cells is provided. The method comprises treating a cell that is exposed to a physiological stress which induces expression of a molecular chaperon by the cell with an effective amount of a certain hydroxylamine derivative to increase the stress. Alternatively; an hydroxylamine derivative can be administrated to a cell before it is exposed to a physiological stress which induces expression of a molecular chaperon by the cell. Preferably, the cell to which an hydroxylamine derivative is administered is an eukaryotic cell. The hydroxylamine derivative corresponds to the formulae (I) or (II). The invention also provides novel hydroxyl amine derivatives falling within the scope of the formulae (I) and (II) as well as pharmaceutical and/or cosmetical compositions comprising the said compounds.

Abstract: The present invention provides novel hydroxylamine derivatives represented by the general formula: wherein:X is O, --NH, or a group of formula NR', wherein R and R' are independently selected from alkyl, cycloalkyl, phenylalkyl, phenyl optionally substituted with halo, haloalkyl,alkyl, alkoxy or nitro; and a N-containing heterocyclic ring;R.sup.1 is H or alkanoyl,R.sup.2 is H or hydroxy optionally acylated with alkanoyl, andR.sup.3 is a group of the formula --NR.sup.4 R.sup.5 wherein R.sup.4 and R.sup.5 are independently selected fromH, alkyl, and a group of the formula --CO--NH--R wherein R is as defined above, orwherein R.sup.4 and R.sup.5 when taken together form a 5- to 7-membered heterocyclic ring which may optionally contain one additional hetero atom selected from nitrogen, oxygen and sulfur and which is optionally substituted with alkyl or phenylalkyl.