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1.
Int J Toxicol ; 35(5): 568-83, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27306320

RESUMEN

l-(+) Ergothioneine is a naturally occurring thiol amino acid with antioxidant properties and potential benefits as a dietary supplement. Despite its century-old identification and wide distribution in human food, little is known of its mechanism of action and safety. The nature-identical biomimetic of l-(+) ergothioneine, produced by Mironova Labs and supplied as Mironova (EGT+), has been investigated in the present studies for its mutagenic and toxicologic potential. In a plate incorporation and preincubation assay with Salmonella typhimurium strains TA98, 100, 1,535, and 1,537 and Escherichia coli WP2uvrA strain, at dose concentrations of 1.58, 5, 15.8, 50, 158, 500, 1,580, and 5,000 µg/plate with and without metabolic activation, no cytotoxicity or mutagenicity was observed. Following a preliminary 28-day study, a repeated dose 90-day gavage study at dose levels of 0, 400, 800, and 1,600 mg/kg body weight (bw)/d in Sprague Dawley rats, in which dose-proportional systemic absorption was confirmed by plasma analysis, no adverse clinical, body weight/gain, food consumption and efficiency, clinical pathology, or histopathological changes associated with the administration of the nature-identical ergothioneine were observed. In conclusion, EGT+ administered over 90 days was well tolerated with a no adverse effect level at 1,600 mg/kg bw/d, the highest dose tested for male and female rats. In addition, the nature-identical test substance, EGT+ was not mutagenic in a bacterial reverse mutation assay at plate concentrations of up to 5,000 µg/mL in the presence or absence of metabolic activation.


Asunto(s)
Evaluación Preclínica de Medicamentos , Ergotioneína/toxicidad , Ergotioneína/uso terapéutico , Administración Oral , Animales , Antioxidantes/farmacología , Daño del ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Escherichia coli , Femenino , Masculino , Pruebas de Mutagenicidad , Nivel sin Efectos Adversos Observados , Ratas , Ratas Sprague-Dawley , Salmonella typhimurium , Pruebas de Toxicidad Subcrónica
2.
Toxicol Mech Methods ; 24(7): 495-503, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25045923

RESUMEN

Safety and anti-diabetic efficacy of a novel, proprietary Trigonella foenum-graecum seed extract [novel fenugreek extract (FE), Fenfuro™, CR0010810) enriched in furostanolic saponins (>60% w/w, HPLC) were assessed. Concerning safety, we undertook studies dealing with acute oral toxicity, 28-d sub-chronic toxicity and Ames' bacterial reverse mutation assay that revealed no toxicity. Concerning efficacy, we examined beneficial effects of the extract on rats with type 2 diabetes (T2D). Male Sprague-Dawley rats received a high-fat diet for 2 weeks followed by streptozotocin (STZ, 35 mg/kg i.p.) to produce T2D. Seven days post-STZ, rats showing ≥300 mg/dl fasting plasma glucose level (PGL) were included in the study. FE (150- or 450- mg/kg p.o.) and glipizide (5 mg/kg p.o.) were administered once daily for 20 d and then twice daily for another 10 d (total 30 d). Blood samples were collected at 0, 10, 20 and 30 d of treatment and estimated for fasting plasma triglyceride (PTG), total cholesterol and insulin levels. After 30 d, FE and glipizide-treated diabetic animals were treated in combination with or without metformin (100 mg/kg) twice daily for another 10 d. FE did not influence body weight, feed and water intake. FE (150 mg/kg p.o.) reduced PTG levels in T2D rats by 22%, 24.6% and 29% at 10, 20 and 30 d of treatment, respectively, while glipizide (5 mg/kg p.o.) reduced the PTG levels by 57.4%, 46.2% and 39.4% at these time points. FE (450 mg/kg) treatment in STZ-induced diabetic rats produced significant hypoglycemic activity (approximately 31.5%) as compared to insulin (48.2% with 1 U/kg i.p.). FE (150 mg/kg p.o.) and metformin (100 mg/kg p.o.) combined produced significant reduction (20.7%) of PGL in T2D rats. No adverse effects were observed. We conclude after extensive in vitro and in vivo safety and efficacy studies that FE is safe and effective in treating T2D.


Asunto(s)
Hipoglucemiantes/toxicidad , Extractos Vegetales/toxicidad , Semillas/química , Trigonella/química , Animales , Glucemia/metabolismo , Diabetes Mellitus Experimental/tratamiento farmacológico , Femenino , Hipoglucemiantes/uso terapéutico , Masculino , Pruebas de Mutagenicidad , Extractos Vegetales/uso terapéutico , Ratas , Ratas Sprague-Dawley , Estreptozocina , Trigonella/embriología
3.
Food Chem Toxicol ; 57: 1-10, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23470325

RESUMEN

Apoaequorin, a calcium-binding protein originally isolated from jellyfish is available commercially as a dietary supplement. The objective of the present study was to investigate potential adverse effects, if any, of Apoaequorin, a recombinant protein preparation, in rats following subchronic administration. For this study, Sprague-Dawley (Hsd:SD) rats (10/sex/group) were administered via oral gavage 0 (control), 92.6, 462.9, and 926.0mg/kg body weight (bw)/day of Apoaequorin preparation, for 90 days. The corresponding amount of Apoaequorin protein was 0, 66.7, 333.3 and 666.7 mg/kg bw/day, respectively. Administration of the Apoaequorin preparation did not result in any mortality. There were no clinical or ophthalmological signs, body weight, body weight gain, food consumption, food efficiency, clinical pathology or histopathological changes attributable to administration of Apoaequorin. Any changes noted were incidental and in agreement with those historically observed in the age and strain of rats used in this study. Based on the results of this study, the No Observed-Adverse-Effect Level (NOAEL) for Apoaequorin was determined as 666.7 mg/kg bw/day, the highest dose tested.


Asunto(s)
Aequorina/toxicidad , Apoproteínas/toxicidad , Administración Oral , Aequorina/administración & dosificación , Animales , Apoproteínas/administración & dosificación , Peso Corporal/efectos de los fármacos , Suplementos Dietéticos/toxicidad , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos/efectos de los fármacos , Ojo/efectos de los fármacos , Femenino , Masculino , Nivel sin Efectos Adversos Observados , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/toxicidad , Pruebas de Toxicidad Subcrónica/métodos
4.
Food Chem Toxicol ; 55: 272-8, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23348409

RESUMEN

Hoodia parviflora is being developed commercially for use in weight loss food and dietary supplement products. Its effects are ascribed to a number of glycosides that have been shown to be present in plant extracts from several Hoodia species, the best known of which is H. gordonii. H. parviflora has been identified as an alternative to H. gordonii, and, as part of the process to develop H. parviflora, in vitro genotoxicity tests, as recommended by recent European Food Safety Authority guidance, were conducted on a dried powder preparation of H. parviflora aerial parts. The preparation was tested for reverse mutation at doses up to 5,000µg/plate in Salmonella typhimurium strains TA98, TA100, TA1535, and TA1537, and in Escherichia coli WP2 uvrA TA, both in the presence and in the absence of an exogenous source of metabolic activation (rat liver S9). In addition, the dried powder was evaluated in an in vitro cytotoxicity chromosome aberration assay using human lymphocytes. Test conditions included both a 4 (up to 2500µg/mg) and 44-h exposure period (up to 1000µg/mg) and the incorporation of an exogenous source of metabolic activation (4-h exposure only). H. parviflora dried powder was non-genotoxic in both in vitro assays.


Asunto(s)
Apocynaceae/química , Mutágenos/toxicidad , Estructuras de las Plantas , Animales , Biotransformación , Pruebas de Mutagenicidad , Ratas , Salmonella typhimurium/genética
5.
Toxicol Mech Methods ; 20(6): 334-44, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20528255

RESUMEN

The present study was conducted to examine the safety of a novel plant-based calcium supplement, derived from marine algae and containing high levels of calcium, magnesium, and other bone supporting minerals (commercially known as AlgaeCal (AC)). The present study evaluated the broad-spectrum safety of AC using a variety of toxicological assays including acute oral, acute dermal, primary skin irritation, and primary eye irritation toxicity. Under the conditions of the study, the acute oral LD(50) of AC was found to be greater than 5000 mg/kg body weight in rats, while the single acute dermal LD(50) was greater than 2000 mg/kg body weight. The primary skin irritation index of AC was found to be 0.4 and classified as slightly irritating to the skin. In primary eye irritation studies, the maximum mean total score of AC was observed to be 13.7 and classified as mildly irritating to the eye. Furthermore, another independent set of studies was conducted to obtain preliminary data for the teratogenic effects of AC in pregnant rats likely to arise from repeated gestational exposure, via oral gavage, over a test period of implantation through gestation (gestation days 5-19). Under the conditions of this pilot study, the effect of daily administration of AC by oral gavage at dose levels of 0, 500, 2500, and 5000 mg/kg/day during gestation days 5-19 of a 21-day pregnancy has appeared to result in no adverse toxicological effects to the pregnant rat or its developing offspring. A slight, non-significant increase in the incidence of incomplete sterna ossification (5(th) center) was observed. Under the conditions of the study, a no-observed-adverse effect level (NOAEL) of 5000 mg/kg/day of AC during pregnancy of the rat was observed. Overall, no significant toxicities of AC were observed in these toxicity models. Therefore, the results from the current study demonstrate a broad-spectrum safety profile of AC.


Asunto(s)
Calcio/toxicidad , Seguridad de Productos para el Consumidor , Suplementos Dietéticos/toxicidad , Eucariontes/química , Pruebas de Toxicidad/métodos , Animales , Peso Corporal/efectos de los fármacos , Calcio/aislamiento & purificación , Ojo/efectos de los fármacos , Femenino , Masculino , Especificidad de Órganos , Embarazo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Conejos , Ratas , Ratas Sprague-Dawley , Reproducción/efectos de los fármacos , Piel/efectos de los fármacos , Pruebas de Toxicidad Aguda
6.
Int J Toxicol ; 28(4): 318-31, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19636074

RESUMEN

PolyGlycopleX (PGX), a novel dietary fiber, produces no mutagenic effects in bacterial tester strains Salmonella typhimurium TA 98, TA 100, TA 1535, and TA 1537 and Escherichia coli WP2 uvrA at concentrations of 0.316, 1.00, 3.16, 10.0, 31.6, and 100 microg/plate. No biologically relevant increases in revertant colonies of any of the 5 strains are observed at any concentration; however, a reduction at 100 microg/plate in TA 1537 is noted. PGX, analyzed for polychromatic erythrocyte micronuclei induction in mice following a single 1x, 0.5x, and 0.2x maximum tolerable dose intraperitoneal treatment, produces no biologically relevant increase in any dose group. Males at 1x maximum tolerable dose show a reduction of micronuclei-containing cells. High-dose animals show signs of systemic toxicity, including a reduction of spontaneous activity, rough fur, palpebral closure, prone position, and constricted abdomen. These genotoxicity studies show PGX to be nonmutagenic in both the Ames bacterial reverse mutation assay and the mammalian erythrocyte micronucleus test.


Asunto(s)
Alginatos/toxicidad , Fibras de la Dieta/toxicidad , Polisacáridos Bacterianos/toxicidad , Animales , Biotransformación , Combinación de Medicamentos , Escherichia coli/efectos de los fármacos , Ratones , Pruebas de Mutagenicidad , Salmonella typhimurium/efectos de los fármacos
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