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Métodos Terapéuticos y Terapias MTCI
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1.
Toxins (Basel) ; 13(2)2021 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-33673235

RESUMEN

We are investigating plant species from the Canadian prairie ecological zone by phenotypic cell assays to discover toxins of biological interest. We provide the first report of the effects of extracts prepared from the shrub Symphoricarpos occidentalis in several human cell lines. S. occidentalis (Caprifoliaceae) extracts are cytotoxic, and, strikingly, treated cells undergo light-dependent vacuolation near the nucleus. The range of irradiation is present in standard ambient light and lies in the visible range (400-700 nm). Vacuolization in treated cells can be induced with specific wavelengths of 408 or 660 nm at 1 J/cm2 energies. Vacuolated cells show a striking phenotype of a large perinuclear vacuole (nuclear associated vacuole, NAV) that is distinct from vesicles observed by treatment with an autophagy-inducing agent. Treatment with S. occidentalis extracts and light induces an intense lamin A/C signal at the junction of a nuclear vacuole and the nucleus. Further study of S. occidentalis extracts and vacuolation provide chemical tools that may contribute to the understanding of nuclear envelope organization and human cell biology.


Asunto(s)
Núcleo Celular/efectos de los fármacos , Extractos Vegetales/toxicidad , Plantas Tóxicas/toxicidad , Symphoricarpos/toxicidad , Toxinas Biológicas/toxicidad , Vacuolas/efectos de los fármacos , Células A549 , Núcleo Celular/metabolismo , Núcleo Celular/patología , Núcleo Celular/efectos de la radiación , Células HT29 , Humanos , Lamina Tipo A/metabolismo , Luz , Extractos Vegetales/aislamiento & purificación , Toxinas Biológicas/aislamiento & purificación , Vacuolas/metabolismo , Vacuolas/patología , Vacuolas/efectos de la radiación
2.
J Exp Bot ; 62(8): 2841-54, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21357771

RESUMEN

Class III peroxidases (Prxs) are plant enzymes capable of using H(2)O(2) to oxidize a range of plant secondary metabolites, notably phenolic compounds. These enzymes are localized in the cell wall or in the vacuole, which is a target for secondary metabolite accumulation, but very little is known about the function of vacuolar Prxs. Here, the physiological role of the main leaf vacuolar Prx of the medicinal plant Catharanthus roseus, CrPrx1, was further investigated namely by studying its capacity to oxidize co-localized phenolic substrates at the expense of H(2)O(2). LC-PAD-MS analysis of the phenols from isolated leaf vacuoles detected the presence of three caffeoylquinic acids and four flavonoids in this organelle. These phenols or similar compounds were shown to be good CrPrx1 substrates, and the CrPrx1-mediated oxidation of 5-O-caffeoylquinic acid was shown to form a co-operative regenerating cycle with ascorbic acid. Interestingly, more than 90% of total leaf Prx activity was localized in the vacuoles, associated to discrete spots of the tonoplast. Prx activity inside the vacuoles was estimated to be 1809 nkat ml(-1), which, together with the determined concentrations for the putative vacuolar phenolic substrates, indicate a very high H(2)O(2) scavenging capacity, up to 9 mM s(-1). Accordingly, high light conditions, known to increase H(2)O(2) production, induced both phenols and Prx levels. Therefore, it is proposed that the vacuolar couple Prx/secondary metabolites represent an important sink/buffer of H(2)O(2) in green plant cells.


Asunto(s)
Catharanthus/enzimología , Peróxido de Hidrógeno/metabolismo , Peroxidasa/metabolismo , Fenoles/metabolismo , Plantas Medicinales/enzimología , Vacuolas/enzimología , Ácido Ascórbico/metabolismo , Catharanthus/efectos de la radiación , Catharanthus/ultraestructura , Isoenzimas/metabolismo , Luz , Espectrometría de Masas , Células del Mesófilo/citología , Células del Mesófilo/enzimología , Células del Mesófilo/efectos de la radiación , Células del Mesófilo/ultraestructura , Oxidación-Reducción/efectos de la radiación , Fenoles/química , Fenoles/aislamiento & purificación , Extractos Vegetales , Hojas de la Planta/enzimología , Hojas de la Planta/efectos de la radiación , Hojas de la Planta/ultraestructura , Plantas Medicinales/efectos de la radiación , Plantas Medicinales/ultraestructura , Protoplastos/metabolismo , Espectrofotometría Ultravioleta , Especificidad por Sustrato/efectos de la radiación , Factores de Tiempo , Vacuolas/efectos de la radiación , Vacuolas/ultraestructura
3.
Photodermatol Photoimmunol Photomed ; 13(4): 117-28, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9453079

RESUMEN

Ultraviolet light (UVR) induces a myriad of cutaneous changes, including delayed disruption of the permeability barrier with higher doses. To investigate the basis for the UVB-induced barrier alteration, we assessed the epidermal lamellar body secretory system at various time points before and after barrier disruption with a single high dose of UVB (7.5 MED) to murine epidermis. Morphological data were correlated with changes in epidermal proliferation and lipid synthesis, indicative of lamellar body generation. Twenty-four hours following UVB, the stratum corneum (SC) is normal, but a layer of abnormal, vacuolated, and lamellar body (LB)-deficient cells is present, immediately beneath the stratum granulosum (SG)/SC interface. Immediately subjacent to this band of damaged cells, normal keratinocytes that contain intact LBs are present. By 72 h, concomitant with the appearance of a barrier abnormality, extensively damaged cells persist at the SC/SG interface, and abnormal lamellar membrane structures appear in the lower SC. Upper stratum spinosum (SS) and lower SG cells appear normal, with increased numbers of LBs. A barrier abnormality is still present at 96 h, in association with membrane abnormalities in the lower SC interstices, but up to four normal appearing, subjacent SG cell layers are present. By 120 h, accelerated LB formation and precocious LB extrusion occur throughout the thickened SG; normal lamellar membranes are present in the lower SC; and barrier recovery is almost complete. Whereas, epidermal synthesis of the major barrier lipid species (i.e., cholesterol, fatty acids, and ceramides, including acylceramides) is reduced or unchanged at 24 and 48 h, it increases significantly 72 h after exposure to UVB. Therefore, the delayed disruption of the permeability barrier following acute UVB exposure results from the arrival of a band of lamellar body-incompetent (i.e., damaged) cells at the SG/SC interface. The subsequent, rapid recovery of the barrier, in turn, results from compensatory hyperplasia of subjacent, undamaged SS/SG cells, generating increased numbers and contents of LB. These results underscore the critical role of the stratum compactum in mediating barrier function, and suggest that beneficial therapeutic effects of UV exposure may be due to enhanced lipid production and barrier regeneration.


Asunto(s)
Piel/efectos de la radiación , Rayos Ultravioleta , Pérdida Insensible de Agua/efectos de la radiación , Aciltransferasas/metabolismo , Aciltransferasas/efectos de la radiación , Animales , Recuento de Células , División Celular/efectos de la radiación , Ceramidas/biosíntesis , Ceramidas/efectos de la radiación , Colesterol/biosíntesis , Colesterol/efectos de la radiación , Epidermis/química , Epidermis/efectos de la radiación , Epidermis/ultraestructura , Ácidos Grasos/biosíntesis , Ácidos Grasos/efectos de la radiación , Estudios de Seguimiento , Hiperplasia , Queratinocitos/química , Queratinocitos/efectos de la radiación , Queratinocitos/ultraestructura , Lípidos/biosíntesis , Lípidos/efectos de la radiación , Ratones , Ratones Pelados , Orgánulos/química , Orgánulos/metabolismo , Orgánulos/efectos de la radiación , Orgánulos/ultraestructura , Permeabilidad/efectos de la radiación , Regeneración , Serina C-Palmitoiltransferasa , Piel/química , Piel/ultraestructura , Esfingolípidos/biosíntesis , Esfingolípidos/efectos de la radiación , Vacuolas/química , Vacuolas/efectos de la radiación , Vacuolas/ultraestructura
4.
Lasers Surg Med ; 17(1): 32-8, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7564854

RESUMEN

BACKGROUND AND OBJECTIVE: The development of the Alexandrite laser for the removal of blue-black tattoos is described. STUDY DESIGN/MATERIALS AND METHODS: The responses of an animal study, using professionally tattooed skin and a human study involving 22 (professional and nonprofessional) blue-black tattoos, to the Alexandrite laser are reported. RESULTS: Histopathologic evaluation of tattooed pig skin biopsies demonstrated the method of removal of dermal tattoo pigment. An average 11.6 treatments were required to remove completely the ten human blue-black professional tattoos compared to an average of 10.3 treatments to reach the same endpoint in six subjects with nonprofessional tattoos. CONCLUSION: Of significance was the fact that unlike the Q-switched Ruby and Nd:YAG lasers where punctate bleeding and tissue splattering have been reported to occur during laser tattoo removal, epidermal integrity was maintained during exposure of tattooed skin to the Q-switched Alexandrite laser at therapeutic fluences used.


Asunto(s)
Procedimientos Quirúrgicos Dermatologicos , Coagulación con Láser , Tatuaje , Adulto , Óxido de Aluminio , Animales , Berilio , Biopsia , Femenino , Estudios de Seguimiento , Humanos , Hipopigmentación/etiología , Tinta , Coagulación con Láser/instrumentación , Coagulación con Láser/métodos , Masculino , Pigmentos Biológicos/efectos de la radiación , Proyectos Piloto , Piel/patología , Pigmentación de la Piel/efectos de la radiación , Porcinos , Porcinos Enanos , Vacuolas/efectos de la radiación
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