Phytoecdysteroids are plant steroids with identical or analogue structures to the molting hormone... more Phytoecdysteroids are plant steroids with identical or analogue structures to the molting hormone in arthropods. The ecdysteroids exert several beneficial effects on mammals, from which the most cited and deeply examined one is the increase of muscle size and strength. This shows similarities with the mode of action of the androgenic steroids but the ecdysteroids do not bind to the cytoplasmic/nuclear receptor of the mammalian steroids. These findings led to the hypothesis that ecdysteroids possibly bind to membrane bound receptors and they are likely to influence signal transduction pathways. Probably because of their closely related chemical structures, ecdysteroids exert some similar effects in vertebrates to those of the hormone 1 alpha,25-dihydroxyvitamin D3 (1,25D) which is produced in the kidney from 25-hydroxyvitamin D3, after being converted in the liver from Vitamin D3. 1,25D generates biological responses via both genomic and rapid, nongenomic mechanisms. Structure-activity relationship studies with different Vitamin D analogues could open the possibility to show that the two ways of action (genomic and nongenomic) can be influenced separately. The connection between the Vitamin D status and muscle function is already well-described in clinical studies, and several efforts have been made to evaluate the effect of Vitamin D deficiency or supplementation on muscle morphological changes and the underlying molecular mechanisms. This paper aims to summarize the main structural commonalities between the ecdysteroids, 1,25D and other Vitamin D analogues. The similarities in their effects and pathways that might be involved in the mechanism of action of these compounds will also be discussed.
Six new ecdysteroids have been isolated from SERRATULA TINCTORIA; these are: the 2,22- and 3,22-d... more Six new ecdysteroids have been isolated from SERRATULA TINCTORIA; these are: the 2,22- and 3,22-diacetates of 20-hydroxyecdysone, 5beta-hydroxyrubrosterone, 3-epi-poststerone, 3-epi-rubrosterone, and 22-oxo-20-hydroxyecdysone. These minor compounds were found together with the known ecdysteroids, 20-hydroxyecdysone, its 2-, 3-, and 22-monoacetates, rubrosterone, poststerone, polypodine B (5beta,20-dihydroxyecdysone), pterosterone (25-deoxy-20,24-dihydroxyecdysone), and makisterone C (24-ethyl-20-hydroxyecdysone). All these ecdysteroids were isolated by a combination of several chromatographic techniques (liquid chromatography on alumina, DCCC, and HPLC), then identified using standard mass spectrometric and 2D (1)H-NMR techniques.
Journal of Liquid Chromatography & Related Technologies, 2005
Various types of two‐dimensional thin‐layer chromatography are presented. Even using appropriatel... more Various types of two‐dimensional thin‐layer chromatography are presented. Even using appropriately selective systems, multicomponent mixtures can result in spots around the main diagonal, but they can be spread all over the TLC plate simply by improvements in the mobile phase composition. The use of cyano‐silica offers the change of normal‐phase to reversed‐phase separations in the first and second dimensional developments.
Phytoecdysteroids are plant steroids with identical or analogue structures to the molting hormone... more Phytoecdysteroids are plant steroids with identical or analogue structures to the molting hormone in arthropods. The ecdysteroids exert several beneficial effects on mammals, from which the most cited and deeply examined one is the increase of muscle size and strength. This shows similarities with the mode of action of the androgenic steroids but the ecdysteroids do not bind to the cytoplasmic/nuclear receptor of the mammalian steroids. These findings led to the hypothesis that ecdysteroids possibly bind to membrane bound receptors and they are likely to influence signal transduction pathways. Probably because of their closely related chemical structures, ecdysteroids exert some similar effects in vertebrates to those of the hormone 1 alpha,25-dihydroxyvitamin D3 (1,25D) which is produced in the kidney from 25-hydroxyvitamin D3, after being converted in the liver from Vitamin D3. 1,25D generates biological responses via both genomic and rapid, nongenomic mechanisms. Structure-activity relationship studies with different Vitamin D analogues could open the possibility to show that the two ways of action (genomic and nongenomic) can be influenced separately. The connection between the Vitamin D status and muscle function is already well-described in clinical studies, and several efforts have been made to evaluate the effect of Vitamin D deficiency or supplementation on muscle morphological changes and the underlying molecular mechanisms. This paper aims to summarize the main structural commonalities between the ecdysteroids, 1,25D and other Vitamin D analogues. The similarities in their effects and pathways that might be involved in the mechanism of action of these compounds will also be discussed.
Six new ecdysteroids have been isolated from SERRATULA TINCTORIA; these are: the 2,22- and 3,22-d... more Six new ecdysteroids have been isolated from SERRATULA TINCTORIA; these are: the 2,22- and 3,22-diacetates of 20-hydroxyecdysone, 5beta-hydroxyrubrosterone, 3-epi-poststerone, 3-epi-rubrosterone, and 22-oxo-20-hydroxyecdysone. These minor compounds were found together with the known ecdysteroids, 20-hydroxyecdysone, its 2-, 3-, and 22-monoacetates, rubrosterone, poststerone, polypodine B (5beta,20-dihydroxyecdysone), pterosterone (25-deoxy-20,24-dihydroxyecdysone), and makisterone C (24-ethyl-20-hydroxyecdysone). All these ecdysteroids were isolated by a combination of several chromatographic techniques (liquid chromatography on alumina, DCCC, and HPLC), then identified using standard mass spectrometric and 2D (1)H-NMR techniques.
Journal of Liquid Chromatography & Related Technologies, 2005
Various types of two‐dimensional thin‐layer chromatography are presented. Even using appropriatel... more Various types of two‐dimensional thin‐layer chromatography are presented. Even using appropriately selective systems, multicomponent mixtures can result in spots around the main diagonal, but they can be spread all over the TLC plate simply by improvements in the mobile phase composition. The use of cyano‐silica offers the change of normal‐phase to reversed‐phase separations in the first and second dimensional developments.
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Papers by Maria Bathori