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1.
Eur J Obstet Gynecol Reprod Biol ; 287: 195-210, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37385088

RESUMEN

BACKGROUND: Leiomyomas (fibroids), the most common benign solid tumours in females, originate from the myometrium and are associated with poor quality of life for patients. The current management of uterine leiomyomas mainly includes surgical interventions such as hysterectomy and myomectomy, either by laparoscopy or laparotomy, which have several complications and are not ideal for preserving fertility. Therefore, there is a need to develop or repurpose medical treatments that do not require surgical intervention. OBJECTIVE: Many drugs are used to treat the symptoms associated with uterine fibroids. The main objective of this systematic review is to give an up-to-date account of potential pharmacological agents (non-surgical methods) for the management of uterine leiomyomas. SEARCH STRATEGY: PubMed was searched for scientific and clinical literature using the keyword 'uterine fibroids' along with the drug names described in each section. For example, 'uterine fibroids' and 'ulipristal acetate' were the keywords used to search for literature on ulipristal acetate (UPA). RESULTS: Various preclinical and clinical studies have shown that some drugs and herbal formulations exhibit activity in the management of uterine leiomyomas. Recent studies found that drugs such as UPA, elagolix, EC313, asoprisnol, nutritional supplements and herbal preparations were helpful in treating the symptoms associated with uterine leiomyomas. CONCLUSION: Many drugs show efficacy in patients with symptomatic uterine fibroids. UPA is one of the most studied and prescribed medicines for uterine fibroids; however, its usage has been restricted due to a few recent incidences of hepatic toxicity. Herbal drugs and natural supplements have also shown promising effects on uterine fibroids. The synergistic effects of nutritional and herbal supplements have been reported in certain cases, and should be studied in detail. Further research is warranted to identify the mode of action of the drugs, and to determine the precise conditions that would explain the causes of toxicity in some patients.


Asunto(s)
Leiomioma , Miomectomía Uterina , Neoplasias Uterinas , Femenino , Humanos , Neoplasias Uterinas/tratamiento farmacológico , Neoplasias Uterinas/patología , Calidad de Vida , Leiomioma/tratamiento farmacológico , Leiomioma/patología , Acetatos/uso terapéutico
2.
PLoS One ; 16(6): e0249230, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34157031

RESUMEN

Cytokinins (CKs) plays a key role in plant adaptation over a range of different stress conditions. Here, we analyze the effects of a cytokinin (i.e., kinetin, KN) on the growth, photosynthesis (rate of O2 evolution), PS II photochemistry and AsA-GSH cycle in Trigonella seedlings grown under cadmium (Cd) stress. Trigonella seeds were sown in soil amended with 0, 3 and 9 mg Cd kg-1 soil, and after 15 days resultant seedlings were sprayed with three doses of KN, i.e.,10 µM (low, KNL), 50 µM (medium, KNM) and 100 µM (high, KNH); subsequent experiments were performed after 15 days of KN application, i.e., 30 days after sowing. Cadmium toxicity induced oxidative damage as shown by decreased seedling growth and photosynthetic pigment production (Chl a, Chl b and Car), rates of O2-evolution, and photochemistry of PS II of Trigonella seedlings, all accompanied by an increase in H2O2 accumulation. Supplementation with doses of KN at KNL and KNM significantly improved the growth and photosynthetic activity by reducing H2O2 accumulation through the up-regulation AsA-GSH cycle. Notably, KNL and KNM doses stimulated the rate of enzyme activities of APX, GR and DHAR, involved in the AsA-GSH cycle thereby efficiently regulates the level of AsA and GSH in Trigonella grown under Cd stress. The study concludes that KN can mitigate the damaging effects of Cd stress on plant growth by maintaining the redox status (>ratios: AsA/DHA and GSH/GSSG) of cells through the regulation of AsA-GSH cycle at 10 and 50 µM KN under Cd stress conditions. At 100 µM KN, the down-regulation of AsA-GSH cycle did not support the growth and PS II activity of the test seedlings.


Asunto(s)
Cinetina/metabolismo , Estrés Fisiológico/fisiología , Trigonella/metabolismo , Antioxidantes/farmacología , Ácido Ascórbico/metabolismo , Cadmio/efectos adversos , Metabolismo de los Hidratos de Carbono/efectos de los fármacos , Glutatión/metabolismo , Peróxido de Hidrógeno/metabolismo , Cinetina/farmacología , Peroxidación de Lípido/efectos de los fármacos , Oxidación-Reducción , Estrés Oxidativo/fisiología , Fotosíntesis/efectos de los fármacos , Fotosíntesis/fisiología , Complejo de Proteína del Fotosistema II/efectos de los fármacos , Complejo de Proteína del Fotosistema II/fisiología , Especies Reactivas de Oxígeno/metabolismo , Plantones/metabolismo , Trigonella/crecimiento & desarrollo
3.
J Photochem Photobiol B ; 178: 76-84, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29125985

RESUMEN

The supplementation of plant hormones may enhance the tolerance capacity of plants against certain environmental stresses by increasing their physiological functioning and detoxification capacity. To answer the question that whether a phytohormone 'kinetin' (KN, 6-furfuylaminopurine), one of the artificial cytokinins could ameliorate the cadmium induced toxicity in tomato seedlings, the effect of KN was assessed in differentially cadmium (Cd1: 3mgkg-1 sand and Cd2: 9mgkg-1 sand) intoxicated tomato seedlings by estimating the changes in reactive oxygen species (ROS, viz. superoxide radical and H2O2 generation) and probable alteration in photosystem II photochemistry, ascorbate-glutathione cycle enzymes and their metabolites. Accumulation of Cd in tomato seedlings increased the production of ROS by negatively impacting PS II photochemistry (decrease in Fv/Fm (ϕP0), Ψ0, ϕE0 and PIABS and increase in energy fluxes per reaction centre: ABS/RC, ET0/RC, TR0/RC and DI0/RC) manifested by lowered fresh mass despite the accelerated activity of AsA-GSH cycle enzymes (viz. ascorbate peroxidase, APX; glutathione reductase, GR; dehydroascorbate reductase, DHAR and monodehydroascorbate reductase; MDHAR). Simultaneous application of kinetin (10µM) alleviated the negative effects on the fresh mass and lowered the ROS level by positively affecting PS II photochemistry and further rise in AsA-GSH cycle enzymes and their metabolites.


Asunto(s)
Ácido Ascórbico/metabolismo , Cadmio/toxicidad , Glutatión/metabolismo , Cinetina/farmacología , Plantones/efectos de los fármacos , Solanum lycopersicum/efectos de los fármacos , Solanum lycopersicum/metabolismo , Biomarcadores/metabolismo , Solanum lycopersicum/enzimología , Estrés Oxidativo/efectos de los fármacos , Oxígeno/metabolismo , Fotosíntesis/efectos de los fármacos , Reguladores del Crecimiento de las Plantas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Plantones/enzimología , Plantones/metabolismo
4.
Springerplus ; 5(1): 1976, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27917348

RESUMEN

BACKGROUND: Anal stricture is a disabling condition which is often unresponsive to conservative medical management. The complications of surgical procedures such as dilatations and anoplasty make it a formidable treatment challenge. Through this case, we report and explore a new medical treatment for ano-rectal strictures with an analogy to Plummer Vinson syndrome. A 69-year-old male presented with chronic constipation, rectal pain, and easy fatigability. The physical exam was negative for anal fissure and a digital rectal examination could not be completed because an index finger could not be advanced through the narrowed anus. Laboratory reports revealed microcytic hypochromic anemia with iron deficiency. A colonoscopy performed with a GIF XQ180 OLYMPUS scope, confirmed anal stricture with non-specific colitis. Conservative management with laxatives, high fiber diet, local anesthetics with a trial of mesalamine was initiated but the patient continued to have symptoms. He was referred to a hematologist for an evaluation of anemia and was started on intravenous (IV) iron infusion. FINDINGS: The patient's symptoms of constipation, anal stricture and iron deficiency anemia resolved with iron infusion over 3 months. A repeat rectal exam was painless and confirmed resolution of anal stricture. CONCLUSION: IV iron supplementation combined with conventional anal dilatation presents as a promising approach toward the treatment of anal strictures.

5.
J Diet Suppl ; 7(1): 31-50, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22435572

RESUMEN

Management of radiation-induced reactive oxygen/nitrogen species requires a holistic approach to mitigate the deleterious effects of free radicals. Flora of the Himalayas, which prevails under extreme climatic conditions, has been explored for its potential utility to develop radioprotective drugs. The Himalayan high altitude medicinal plant, Podophyllum hexandrum Royle, was selected on the basis of its unique properties, and a novel fractionated nonpolar extract (REC-2003) was prepared and evaluated for radioprotective efficacy, in vitro as well as in vivo. The free radical scavenging activity of REC-2003 was found to be > 75% (20 µg/ml) with maximum superoxide scavenging activity (57.56 ± 1.38%) recorded at 1 mg/ml concentration (tetrazolium-based estimation). More than 30% inhibition of nitric oxide radicals was observed at concentrations > 0.5 mg/ml, while hydroxyl radical scavenging activity (deoxy-D-ribose assay) exhibited a dose-dependent (100-600 µg/ml) increase. Significantly high (90%) protection to human erythrocytes was observed at 75 µg/ml, which was found to be the most optimized dose. Similarly, more than 90% inhibition was observed against lipid peroxidation (evaluated by estimating levels of malondialdehyde). The significant antihemolytic potential of REC-2003 could be attributed to its ability to scavenge free radicals, reduce peroxidative stress on lipid membranes, and render protection to DNA (evaluated using plasmid relaxation assay). All these activities holistically contributed toward the radioprotective ability. REC-2003 (8 mg/kg BW; intraperitoneal (i.p.), -30 min) rendered > 80% total-body protection in Swiss Albino Strain 'A' mice [against lethal radiation (10 Gy)] in a 30-day survival assay. Phytochemical characterization of the constituents of REC-2003 revealed the presence of polyphenolics (flavonoids). The characterized constituents also included the aryl-tetralin lignans like podophyllotoxin, its glycoside, 4'-demethyl derivative, and epi-podophyllotoxin. The optimized requisite single dose (8 mg/KgBW; i.p., -30 min) for obtaining significant radioprotection is reasonably low and establishes its future utility as a dietary supplement in the medical management of free radical-mediated diseases and specifically for rescue missions during nuclear and radiological emergencies (NREs).


Asunto(s)
Urgencias Médicas , Depuradores de Radicales Libres/farmacología , Fitoterapia , Podophyllum/química , Traumatismos por Radiación/prevención & control , Protectores contra Radiación/farmacología , Liberación de Radiactividad Peligrosa , Animales , ADN/efectos de los fármacos , Daño del ADN , Suplementos Dietéticos , Eritrocitos/efectos de los fármacos , Eritrocitos/efectos de la radiación , Flavonoides/farmacología , Radicales Libres/metabolismo , Rayos gamma , Humanos , Lignanos/farmacología , Peroxidación de Lípido/efectos de los fármacos , Malondialdehído/metabolismo , Ratones , Ratones Endogámicos , Extractos Vegetales/farmacología , Especies de Nitrógeno Reactivo/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Resultado del Tratamiento
6.
J Diet Suppl ; 5(2): 147-63, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-22432431

RESUMEN

OBJECTIVE: Immense interest has been generated in recent years for the development of drugs of herbal origin for the mitigation of deleterious effects of environmental pollutants like ionizing radiation, mainly to protect against radiation leakages resulting from mishaps in nuclear reactors, deliberate use of dirty bombs, etc. METHOD: The radio modifying effects of a fractionated extract of the high-altitude Himalayan plant species Rhodiola imbricata, along with its electron-donation potential, super-oxide ion scavenging (IC50 ≤ 0.025 mg/ml), nitric oxide (NO) scavenging potential (IC(50) = 0.5 mg/ml), and antihemolytic activity were evaluated in the present study. Reducing power, superoxide ion (O(2)(•-)), and nitric oxide scavenging ability of the fractionated extract increased in a dose-dependent manner. Rhodiola imbricata also exhibited antihemolytic potential preventing radiation-induced membrane degeneration of human erythrocytes. CONCLUSION: Thus, it can be stated that Rhodiola imbricata provides protection against gamma radiation via multifarious mechanisms that act in a synergistic manner. Rhodiola imbricata is widely used as a nutraceutical supplement in the trans-Himalayan region nations, and the current study shows that Rhodiola has immense potential for alleviation of biological damage in a radiation environment.


Asunto(s)
Eritrocitos/efectos de los fármacos , Depuradores de Radicales Libres/farmacología , Fármacos Hematológicos/farmacología , Extractos Vegetales/farmacología , Traumatismos por Radiación/prevención & control , Protectores contra Radiación/farmacología , Rhodiola , Ácido Ascórbico/farmacología , Membrana Celular/efectos de los fármacos , Membrana Celular/efectos de la radiación , Relación Dosis-Respuesta a Droga , Eritrocitos/efectos de la radiación , Depuradores de Radicales Libres/uso terapéutico , Radicales Libres/metabolismo , Fármacos Hematológicos/uso terapéutico , Humanos , Fitoterapia , Extractos Vegetales/uso terapéutico , Traumatismos por Radiación/sangre , Radiación Ionizante , Protectores contra Radiación/uso terapéutico
7.
J Med Food ; 10(1): 101-9, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17472473

RESUMEN

Plants are an abundant source of medicinal compounds, some of which are useful in combating free radical-mediated oxidative stress. In the present study, initially two fractions designated REC-1001 (flavonoid-rich fraction) and REC-1002 (flavonoid-poor fraction) of Hippophae rhamnoides were screened on the basis of their reducing power in the aqueous phase. REC-1001 was selected for further study, since it exhibited 27.38 times higher antioxidant activity than REC-1002. REC-1001 also showed significant (P < .05) membrane protection potential at 50 microg/mL, which was attributed to its ability to scavenge peroxyl radicals (64.82 +/- 1.25% scavenging within 1,440 min). A significant (P < .05) difference of 67.02% in free radical scavenging activity at 1,000 ng/mL between REC-1001 and vitamin E demonstrated the extract fraction's worth in radiation protection. Such activities were attributed to the presence of quercetin, isorhamnetin, and kaempferol in this fraction. Further, REC-1001 was found to be nontoxic up to 200 mg/kg of body weight. This research suggests that the REC-1001 fraction of H. rhamnoides extract is a safe and effective antioxidant nutraceutical product.


Asunto(s)
Antioxidantes/farmacología , Frutas/química , Hippophae/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Protectores contra Radiación/farmacología , Animales , Fraccionamiento Químico , Flavonoles/análisis , Depuradores de Radicales Libres/farmacología , Quempferoles/análisis , Dosificación Letal Mediana , Ratones , Peróxidos , Extractos Vegetales/toxicidad , Quercetina/análisis
8.
Evid Based Complement Alternat Med ; 3(4): 503-11, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17173115

RESUMEN

We have evaluated the effect of variation in aryl-tetralin lignans on the radioprotective properties of Podophyllum hexandrum. Two fractionated fractions of P. hexandrum [methanolic (S1) and chloroform fractions (S2)], with varying aryl-tetralin lignan content were utilized for the present study. The peroxyl ion scavenging potentials of S1 and S2 were found to be comparable [i.e. 45.88% (S1) and 41% (S2)] after a 48 h interval in a time-dependent study, whereas in a 2 h study, S2 exhibited significant (P < 0.05) antioxidant activity in different metal ion + flux states. In the aqueous phase, S2 exhibited non-site-specific reactive oxygen species scavenging activity, i.e. 73.12% inhibition at 500 mug ml(-1). S1 exhibited 58.40 +/- 0.8% inhibition (at 0.025 mug ml(-1)) of the formation of reactive nitrite radicals, comparable to S2 (52.45 +/- 0.825%), and also showed 45.01% site-specific activity (1000 mug ml(-1)), along with significant (P < 0.05) electron donation potential (50-2000 mug ml(-1)) compared to S2. Such activities of S1 could be attributed to the significantly (P < 0.05) higher levels of podophyllotoxin beta-d-glucopyranoside (16.5 times) and demethyl podophyllotoxin glucoside (2.9 times) compared with S2. Together, these findings clearly prove that aryl-tetralin lignan content influences the radiation protective potential of the Podophyllum fractions to a great extent.

9.
Planta Med ; 72(2): 114-20, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16491445

RESUMEN

A semi-purified extract of low-altitude Podophyllum hexandrum (REC-2001) containing a relatively low content of podophyllotoxin (3.25 %) exhibited potent antioxidant ability in lipid media (at 1000 microg/mLagainst 0.25 kGy) and significant (p < 0.05) hydroxyl ion scavenging potential (78.83 % at 500 microg/mL). In vitro investigations revealed the ability of REC-2001 to significantly (p < 0.05) reduce radiation-induced hemolysis (2 microg/mL; 46.184 %) and nitric oxide scavenging levels (IC (50): 792 +/- 1.25 microg/mL). Protection of the hemopoietic system of Strain 'A' mice administered 20 mg/kg BW REC-2001 30 min prior to lethal irradiation (10 Gy) was recorded and was mediated by free radical scavenging and lowering of lipid oxidation. Further studies investigating the effects of REC-2001 on stem cell modulation are warranted.


Asunto(s)
Antioxidantes/farmacología , Medicamentos Herbarios Chinos/farmacología , Rayos gamma , Hematopoyesis/efectos de los fármacos , Podophyllum/química , Protectores contra Radiación/farmacología , Animales , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Berberidaceae , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Eritrocitos/efectos de los fármacos , Eritrocitos/efectos de la radiación , Hematopoyesis/efectos de la radiación , Humanos , Leucocitos/efectos de los fármacos , Leucocitos/efectos de la radiación , Ratones , Podofilotoxina/química , Podofilotoxina/aislamiento & purificación , Protectores contra Radiación/química
10.
Z Naturforsch C J Biosci ; 60(9-10): 728-38, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16320616

RESUMEN

The aqueous-ethanolic extract (AEE) of high altitude Podophyllum hexandrum has earlier been reported to render a radioprotective effect against lethal gamma radiation in in vitro model. AEE has also been reported to possess metal chelating and DNA protecting properties. The present study was undertaken to isolate and characterize the bioactive principle present in AEE and investigate its role in radiation protection. A novel molecule was found to be present in AEE and was assigned as 3-O-beta-D-galactoside of quercetin by acid hydrolysis, LC-MS, LC-APCI-MS/MS and 13C NMR spectra. Various biological activities were investigated at in vitro level. The antioxidant potential of AEE in lipid and aqueous phase was determined against numerous stresses. AEE was found to be significantly (p < 0.05) protective, i.e., against Fe2+ and Cu2+-induced linoleic acid degradation, respectively. Radiation-induced lipid oxidation studies revealed that AEE maximally works at a [lignan]/0.25 kGy ratio 400 (ratio of concentration of AEE divided by the radiation dose, i.e., 0.25 kGy) and no drug-induced lipid oxidation at all concentrations tested was found. In a time-dependent study, total antioxidant activity was maximally exhibited at 1 mg/ml. The site-specific and non-site-specific deoxyribose degradation assay exhibited a dose-dependant hydroxyl scavenging potential of AEE (0.05-500 microg/ml). The anti-lipid peroxidation ability of AEE against radiation (0.25 kGy)-induced lipid peroxidation was higher in case of neural tissue homogenate as compared to kidney homogenate [activity ratio: 0.039 (brain) < 0.24 (kidney)]. The protein protection study using bovine serum albumin was also done for two time intervals (2 h and 4 h) and significant (p < 0.05) protection was observed at 500 microg/ml (> 97%). This study implies that 3-O-beta-D-galactoside present in AEE renders radioprotection by protecting lipids, proteins in renal and neural model system against supra-lethal (0.25 kGy) gamma radiation.


Asunto(s)
Galactósidos/química , Peroxidación de Lípido/efectos de la radiación , Extractos Vegetales/aislamiento & purificación , Podophyllum/química , Quercetina/análogos & derivados , Quercetina/química , Protectores contra Radiación/química , Altitud , Animales , Antioxidantes/farmacología , Encéfalo/metabolismo , Cromatografía Líquida de Alta Presión , Depuradores de Radicales Libres , Galactósidos/aislamiento & purificación , Galactósidos/farmacología , Rayos gamma , India , Riñón/metabolismo , Masculino , Ratones , Modelos Moleculares , Quercetina/aislamiento & purificación , Quercetina/farmacología , Protectores contra Radiación/aislamiento & purificación , Protectores contra Radiación/farmacología , Albúmina Sérica Bovina/efectos de los fármacos
11.
Mol Cell Biochem ; 273(1-2): 209-23, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-16013456

RESUMEN

The present study reports the radioprotective properties of a hydro-alcoholic rhizome extract of Rhodiola imbricata (code named REC-7004), a plant native to the high-altitude Himalayas. The radioprotective effect, along with its relevant superoxide ion scavenging, metal chelation, antioxidant, anti-lipid peroxidation and anti-hemolytic activities was evaluated under both in vitro and in vivo conditions. Chemical analysis showed the presence of high content of polyphenolics (0.971 +/- 0.01 mg% of quercetin). Absorption spectra analysis revealed constituents that absorb in the range of 220-290 nm, while high-performance liquid chromatography (HPLC) analysis confirmed the presence of four major peaks with retention times of 4.780, 5.767, 6.397 and 7.577 min. REC-7004 was found to lower lipid oxidation significantly (p < 0.05) at concentrations viz., 8 and 80 microg/ml respectively as compared to reduced glutathione, although the optimally protective dose was 80 microg/ml, which showed 59.5% inhibition of induction of linoleic acid degradation within first 24 h. The metal chelation activity of REC-7004 was found to increase concomitantly from 1 to 50 microg/ml. REC-7004 (10-50 microg/ml) exhibited significant metal chelation activity (p < 0.05), as compared to control, and maximum percentage inhibition (30%) of formation of iron-2,2'-bi-pyridyl complex was observed at 50 microg/ml, which correlated well with quercetin (34.9%), taken as standard. The reducing power of REC-7004 increased in a dose-dependent manner. The absorption unit value of REC-7004 was significantly lower (0.0183 +/- 0.0033) as compared to butylated hydroxy toluene, a standard antioxidant (0.230 +/- 0.091), confirming its high reducing ability. Superoxide ion scavenging ability of REC-7004 exhibited a dose-dependent increase (1-100 microg/ml) and was significantly higher (p < 0.05) than that of quercetin at lower concentrations (1-10 microg/ml), while at 100 microg/ml, both quercetin and REC-7004 scavenged over 90% superoxide anions. MTT assay in U87 cell line revealed an increase in percent survival of cells at doses between 25 and 125 microg/ml in case of drug + radiation group. In vivo evaluation of radio-protective efficacy in mice revealed that intraperitoneal administration of REC-7004 (maximally effective dose: 400 mg/kg b.w.) 30 min prior to lethal (10 Gy) total-body gamma-irradiation rendered 83.3% survival. The ability of REC-7004 to inhibit lipid peroxidation induced by iron/ascorbate, radiation (250 Gy) and their combination [i.e., iron/ascorbate and radiation (250 Gy)], was also investigated and was found to decrease in a dose-dependent manner (0.05-2 mg/ml). The maximum percent inhibition of formation of MDA-TBA complex at 2 mg/ml in case of iron/ascorbate, radiation (250 Gy) and both i.e., iron/ascorbate with radiation (250 Gy) was 53.78, 63.07, and 51.76% respectively and were found to be comparable to that of quercetin. REC-7004 (1 microg/ml) also exhibited significant anti-hemolytic capacity by preventing radiation-induced membrane degeneration of human erythrocytes. In conclusion, Rhodiola renders in vitro and in vivo radioprotection via multifarious mechanisms that act in a synergistic manner.


Asunto(s)
Quelantes del Hierro/farmacología , Extractos Vegetales/farmacología , Plantas Medicinales , Protectores contra Radiación/farmacología , Rhodiola/química , Adulto , Animales , Antioxidantes/farmacología , Proliferación Celular/efectos de los fármacos , Proliferación Celular/efectos de la radiación , Radioisótopos de Cobalto , Eritrocitos/efectos de los fármacos , Eritrocitos/efectos de la radiación , Depuradores de Radicales Libres/farmacología , Rayos gamma , Glioma/metabolismo , Glioma/patología , Hemólisis/efectos de los fármacos , Hemólisis/efectos de la radiación , Humanos , Peroxidación de Lípido/efectos de los fármacos , Peroxidación de Lípido/efectos de la radiación , Masculino , Ratones , Ratones Endogámicos A , Estrés Oxidativo , Células Tumorales Cultivadas
12.
J Environ Pathol Toxicol Oncol ; 24(4): 299-314, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16393123

RESUMEN

The development of nontoxic yet effective radioprotectors is needed because of the increasing risk of human exposure to ionizing radiation. We have reported that high-altitude Podophyllum hexandrum (HAPH) confers a radioprotective effect in in vitro and in vivo models. The present study reports on the antioxidant and radioprotective properties of low-altitude Podophyllum hexandrum (LAPH), from which the toxic compound podophyllotoxin has been partially removed during the extraction process. Using HPLC,we estimated the relative content of two marker compounds, podophyllotoxin and podophyllotoxin glycoside, in low-altitude Podophyllum extract (LAPE) and found them to be 23.3% and 9.50%, respectively. The ferrous ion chelation potential of LAPE was estimated using the 2,2 bipyridyl assay, and the activity was found to be increased concomitantly with the increase in its concentration, with a maximal inhibition at 25 microg/mL (42.20%) as compared to quercetin (34.9%). The electron donation potential of LAPE was also evaluated, because the antioxidant activities of natural products are known to bear a direct correlation with their ability to donate electrons. The concentration required to attain unit absorbance values at 700 nm were 0.230541+/-0.09 and 0.041+/-0.06 for butylated hydroxyl toluene and LAPE, respectively, indicating a higher antioxidant activity of LAPE. The free radical scavenging ability of LAPE was also assessed and exhibited a dose-dependant increase (1-100 microg/mL), comparable to that of quercetin at 25 microg/mL. The role of LAPE in protecting DNA was evaluated, and it was found that LAPE (30 microg/mL) rendered its maximum radioprotection against the 250 Gy-induced damage in the plasmid (pBR322) relaxation assay. LAPE significantly inhibited radiation-induced, iron/ascorbate- and combined stress (iron/ascorbate and radiation)-induced formation of TBARS (p<0.05). We conclude that LAPH, with its easy accessibility, ease of cultivation, multifarious radioprotective properties, and role as a renewable source of bioactive constituents, along with its low associated toxicity (due to partial removal of podophyllotoxin), enhances its possible use for human clinical applications.


Asunto(s)
Antioxidantes/farmacología , Depuradores de Radicales Libres/farmacología , Extractos Vegetales/farmacología , Podophyllum , Protectores contra Radiación/farmacología , Altitud , Animales , Antioxidantes/química , Antioxidantes/uso terapéutico , Muerte Celular/efectos de los fármacos , Muerte Celular/efectos de la radiación , Cromatografía Líquida de Alta Presión , Daño del ADN , Electrones , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/uso terapéutico , Rayos gamma , Quelantes del Hierro/química , Quelantes del Hierro/farmacología , Peroxidación de Lípido/efectos de la radiación , Hígado/metabolismo , Hígado/efectos de la radiación , Masculino , Ratones , Fitoterapia , Podofilotoxina/análisis , Podofilotoxina/farmacología , Podophyllum/química , Protectores contra Radiación/química , Protectores contra Radiación/uso terapéutico , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo
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