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1.
Environ Sci Pollut Res Int ; 30(5): 12402-12411, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36107295

RESUMEN

Cisplatin is an anticancer agent with many side effects such as nephrotoxicity, as well as being widely used in the treatment of many tumor types. Sinapic acid has antioxidant, anti-inflammatory, antihyperglycemic, and antiapoptotic effects. This study aimed to investigate the possible beneficial effects of sinapic acid against cisplatin-induced nephrotoxicity. Twenty-eight Wistar albino male rats were used. The groups are as follows: control, cisplatin, cisplatin + sinapic acid, and sinapic acid groups (n = 7). The control group received 1 ml of single-dose intraperitoneal saline on the first day of the study. The cisplatin group was given a single dose of 7 mg/kg cisplatin intraperitoneal. Animals in the cisplatin + sinapic acid group were given sinapic acid for 7 days 25 mg/kg, 3 days after oral gavage administration of 7 mg/kg cisplatin intraperitoneal. The sinapic acid group was given 25 mg/kg/day of sinapic acid by oral gavage for 7 days after the 3rd day of the study. The kidney of the rats was examined by stereological, immunohistochemical, histopathological, and biochemical methods. According to the stereological findings of the study, while the volume of the glomerulus cortex and filtration gap increased, the volume of the medulla decreased, and there was no significant difference in tubular volume in the CP group compared to the control group. The volume of the glomerulus, cortex, and filtration gap of the cisplatin + sinapic acid group was significantly reduced compared to the cisplatin group (p˂0.05). Histopathologically, it was observed the enlargement of the filtration gap, tubular dilatation, atrophy, renal fibrosis, deterioration of the microvilli, and necrosis in the tubular epithelial cells in the cisplatin group. In the cisplatin + sinapic acid group, these pathologies decreased compared to the cisplatin group. Compared to the control group, caspase-3 expression, urea, creatine, and malondialdehyde increased, while Bcl-2 and catalase decreased in the cisplatin group. However, caspase-3 expression, urea, creatine, and malondialdehyde were decreased, while Bcl-2 and catalase increased in the cisplatin + sinapic acid group compared to the cisplatin group. The results of our study showed that sinapic acid reduced the nephrotoxicity induced by cisplatin.


Asunto(s)
Lesión Renal Aguda , Antineoplásicos , Ratas , Animales , Cisplatino/toxicidad , Catalasa/metabolismo , Caspasa 3/metabolismo , Creatina/toxicidad , Creatina/metabolismo , Ratas Wistar , Antineoplásicos/farmacología , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/prevención & control , Lesión Renal Aguda/metabolismo , Riñón , Estrés Oxidativo , Apoptosis , Urea/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Malondialdehído/metabolismo
2.
Cell Metab ; 33(6): 1111-1123.e4, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33811821

RESUMEN

As one of the most popular nutrient supplements, creatine has been highly used to increase muscle mass and improve exercise performance. Here, we report an adverse effect of creatine using orthotopic mouse models, showing that creatine promotes colorectal and breast cancer metastasis and shortens mouse survival. We show that glycine amidinotransferase (GATM), the rate-limiting enzyme for creatine synthesis, is upregulated in liver metastases. Dietary uptake, or GATM-mediated de novo synthesis of creatine, enhances cancer metastasis and shortens mouse survival by upregulation of Snail and Slug expression via monopolar spindle 1 (MPS1)-activated Smad2 and Smad3 phosphorylation. GATM knockdown or MPS1 inhibition suppresses cancer metastasis and benefits mouse survival by downregulating Snail and Slug. Our findings call for using caution when considering dietary creatine to improve muscle mass or treat diseases and suggest that targeting GATM or MPS1 prevents cancer metastasis, especially metastasis of transforming growth factor beta receptor mutant colorectal cancers.


Asunto(s)
Neoplasias de la Mama/etiología , Neoplasias Colorrectales/etiología , Creatina/toxicidad , Suplementos Dietéticos/toxicidad , Proteína Smad2/metabolismo , Proteína smad3/metabolismo , Animales , Línea Celular , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C
3.
Regul Toxicol Pharmacol ; 117: 104750, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32745584

RESUMEN

Cyclocreatine (LUM-001), a creatine analog, was evaluated for its nonclinical toxicity in Sprague Dawley (SD) rats. Deionized water as a vehicle control article or cyclocreatine was administered by oral gavage twice daily (approximately 12 ± 1 h apart) at 30, 100 and 300 mg/kg/dose levels in rats up to 26 weeks followed by a 28-day recovery period. Due to an increased incidence of seizures, the 600 mg/kg/day dose group males were dosed only for 16-weeks followed by a 14-week recovery period. Thirteen males and four females from 600 mg/kg/day dose group were sacrificed at interim on Day 113 to study plausible brain lesions and not due to moribundity. There was a dose dependent increase in the number of seizure incidences in ≥60 mg/kg/day males and 600 mg/kg/day females. Microscopically, higher incidences of vacuoles in the brain at 600 mg/kg/day in both sexes, thyroid follicular atrophy and follicular cell hypertrophy at ≥200 mg/kg/day in males and 600 mg/kg/day in females, and seminiferous tubular degeneration and/or interstitial edema in testes at ≥200 mg/kg/day were observed. Mean plasma half-life of cyclocreatine was between 3.5 and 6.5 h. In conclusion, chronic administration of cyclocreatine by oral gavage in Sprague Dawley rats induced the seizures and microscopic lesions in the brain, testes and thyroid. Based on the results of this study the highest tested dose of 600 mg/kg/day (mean Cmax of 151.5 µg/mL; AUC0-24 of 1970 h*µg/mL) was considered the maximum tolerated dose (MTD) in SD rats.


Asunto(s)
Encéfalo/efectos de los fármacos , Creatinina/análogos & derivados , Pruebas de Toxicidad Crónica/métodos , Administración Oral , Animales , Encéfalo/metabolismo , Encéfalo/patología , Creatina/análogos & derivados , Creatina/sangre , Creatina/toxicidad , Creatinina/administración & dosificación , Creatinina/sangre , Creatinina/toxicidad , Femenino , Masculino , Tamaño de los Órganos/efectos de los fármacos , Tamaño de los Órganos/fisiología , Ratas , Ratas Sprague-Dawley , Testículo/efectos de los fármacos , Testículo/metabolismo , Testículo/patología , Glándula Tiroides/efectos de los fármacos , Glándula Tiroides/metabolismo , Glándula Tiroides/patología , Factores de Tiempo
4.
Molecules ; 25(9)2020 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-32349282

RESUMEN

Creatine supplementation of the population with type 2 diabetes mellitus (T2DM) combined with an exercise program is known to be a possible therapy adjuvant with hypoglycemic effects. However, excessive administration of creatine leads to the production of methylamine which is deaminated by the enzyme semicarbazide-sensitive amine oxidase (SSAO) and as a result, cytotoxic compounds are produced. SSAO activity and reaction products are increased in the serum of T2DM patients. Creatine supplementation by diabetics will further augment the activity of SSAO. The current review aims to find a feasible way to ameliorate T2DM for patients who exercise and desire to consume creatine. Several natural agents present in food which are involved in the regulation of SSAO activity directly or indirectly are reviewed. Particularly, zinc-α2-glycoprotein (ZAG), zinc (Zn), copper (Cu), histamine/histidine, caffeine, iron (Fe), and vitamin D are discussed. Inhibiting SSAO activity by natural agents might reduce the potential adverse effects of creatine metabolism in population of T2DM.


Asunto(s)
Adipoquinas/sangre , Amina Oxidasa (conteniendo Cobre)/antagonistas & inhibidores , Creatina/toxicidad , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/dietoterapia , Adipoquinas/metabolismo , Amina Oxidasa (conteniendo Cobre)/sangre , Amina Oxidasa (conteniendo Cobre)/metabolismo , Cafeína , Cobre/metabolismo , Creatina/metabolismo , Creatina/farmacología , Diabetes Mellitus Tipo 2/metabolismo , Histamina/metabolismo , Histidina/metabolismo , Humanos , Hierro/metabolismo , Vitamina D , Zinc/metabolismo
5.
Eur J Immunol ; 49(6): 928-939, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30888047

RESUMEN

Creatine (Cr) is a substrate for adenosine triphosphate synthesis, and it is the most used dietary supplement among professional and recreative athletes and sportsmen. Creatine supplementation may increase allergic airway response, but the cellular and molecular mechanisms are unknown. We used murine model of OVA-induced chronic asthma and showed that Cr supplementation increased total proteins, ATP level, lymphocytes, macrophages, and IL-5 levels in BALF, as well as IL-5 in the supernatant of re-stimulated mediastinal lymph nodes. IL-5 and IL-13 expression by epithelial cells and by peribronchial leukocytes were increased by Cr. Cr augmented the expression of P2 × 7 receptor by peribronchial leukocytes and by epithelial cells, and increased the accumulation of eosinophils in peribronchial space and of collagen fibers in airway wall. In human cells, while Cr induced a release of ATP, IL-6, and IL-8 from BEAS-2B cells, whole blood cells, such as eosinophils, and CD4+ T cells, P2 × 7 receptor inhibitor (A740003) reduced such effects, as denoted by reduced levels of ATP, IL-6, and IL-8. Therefore, Cr supplementation worsened asthma pathology due to activation of airway epithelial cells and peribronchial leukocytes, involving purinergic signaling.


Asunto(s)
Asma/patología , Creatina/toxicidad , Suplementos Dietéticos/toxicidad , Neumonía/patología , Receptores Purinérgicos P2X7/metabolismo , Animales , Asma/metabolismo , Modelos Animales de Enfermedad , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Neumonía/metabolismo
6.
An Acad Bras Cienc ; 90(2 suppl 1): 2317-2329, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29694498

RESUMEN

Creatine acts intracellularly as energy buffer and storage, demonstrating protective effects in animal models of neurodegenerative diseases. However, its permeability throught blood-brain barrier (BBB) is reduced. The aim of the present study was developing a carrier to facilitate the delivery of creatine to the central nervous system. Creatine nanoliposomes were produced, characterized and assayed in models of toxicity in vitro and in vivo. Particles showed negative zeta potential (-12,5 mV), polydispersity index 0.237 and medium-size of 105 nm, which was confirmed by transmission electron microscopy (TEM) images. Toxicity assay in vitro was evaluated with blank liposomes (no drug) or creatine nanoliposomes at concentrations of 0.02 and 0.2 mg/mL, that did not influence the viability of Vero cells. The result. of the comet assay that the nanoliposomes are not genotoxic, togeher with cell viability demonstrated that the nanoliposomes are not toxic. Besides, in vivo assays not demonstrate toxicity in hematological and biochemical markers of young rats. Nevertheless, increase content of creatine in the cerebral cortex tissue after subchronic treatment was observed. Altogether, results indicate increase permeability of creatine to the BBB that could be used as assay for in vivo studies to confirm improved effect than free creatine.


Asunto(s)
Encéfalo/efectos de los fármacos , Creatina/toxicidad , Liposomas/toxicidad , Nanopartículas/toxicidad , Polisorbatos/toxicidad , Animales , Encéfalo/ultraestructura , Chlorocebus aethiops , Microscopía Electrónica de Transmisión , Modelos Animales , Ratas , Ratas Wistar , Células Vero
7.
Acta Cir Bras ; 30(5): 313-8, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26016930

RESUMEN

PURPOSE: To evaluate the renal and hepatic function, through biochemical analysis after 14 days of creatine supplementation in physically inactive rats. METHODS: Twenty four male, adult, Wistar rats were used which were kept in individual metabolic cages and were distributed into four groups, and received the following treatments by gavage:1) CONTROL: distilled water; 2)Creatine 0.5g/Kg/day; 3) Creatine 1g/Kg/day; 4) Creatine 2g/Kg/day. Their urinary outputs as well as food and water intake were daily measured. At the end of the experiment, the animals were euthanized and serum samples were stored for biochemical analysis. RESULTS: Creatine supplementation at the doses given produced no significant changes in plasma levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, total protein, albumin, total cholesterol, HDL cholesterol, LDL cholesterol, VLDL cholesterol, triglycerides, glucose, creatinine, urea, and creatinine clearance, compared to control group (p> 0.05) Similarly, water and food intake, as well as urinary output, did not show significant changes among the four groups studied. CONCLUSION: At the doses used, oral creatine supplementation did not result in renal and/or hepatic toxicity.


Asunto(s)
Creatina/administración & dosificación , Creatina/toxicidad , Suplementos Dietéticos/toxicidad , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Alanina Transaminasa/sangre , Albúminas/análisis , Fosfatasa Alcalina/sangre , Animales , Aspartato Aminotransferasas/sangre , Glucemia/análisis , Colesterol/sangre , Creatina/análisis , Creatinina/sangre , Riñón/metabolismo , Hígado/metabolismo , Masculino , Distribución Aleatoria , Ratas Wistar , Valores de Referencia , Factores de Tiempo , Triglicéridos/sangre , Urea/sangre
8.
Acta cir. bras ; 30(5): 313-318, 05/2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-747024

RESUMEN

PURPOSE: To evaluate the renal and hepatic function, through biochemical analysis after 14 days of creatine supplementation in physically inactive rats. METHODS: Twenty four male, adult, Wistar rats were used which were kept in individual metabolic cages and were distributed into four groups, and received the following treatments by gavage:1) Control: distilled water; 2)Creatine 0.5g/Kg/day; 3) Creatine 1g/Kg/day; 4) Creatine 2g/Kg/day. Their urinary outputs as well as food and water intake were daily measured. At the end of the experiment, the animals were euthanized and serum samples were stored for biochemical analysis. RESULTS: Creatine supplementation at the doses given produced no significant changes in plasma levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, total protein, albumin, total cholesterol, HDL cholesterol, LDL cholesterol, VLDL cholesterol, triglycerides, glucose, creatinine, urea, and creatinine clearance, compared to control group (p> 0.05) Similarly, water and food intake, as well as urinary output, did not show significant changes among the four groups studied. CONCLUSION: At the doses used, oral creatine supplementation did not result in renal and/or hepatic toxicity. .


Asunto(s)
Animales , Masculino , Creatina/administración & dosificación , Creatina/toxicidad , Suplementos Dietéticos/toxicidad , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Alanina Transaminasa/sangre , Albúminas/análisis , Fosfatasa Alcalina/sangre , Aspartato Aminotransferasas/sangre , Glucemia/análisis , Colesterol/sangre , Creatina/análisis , Creatinina/sangre , Riñón/metabolismo , Hígado/metabolismo , Distribución Aleatoria , Ratas Wistar , Valores de Referencia , Factores de Tiempo , Triglicéridos/sangre , Urea/sangre
9.
J Med Chem ; 56(12): 5173-81, 2013 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-23697594

RESUMEN

The creatine transporter deficiency is a neurological disease caused by impairment of the creatine transporter SLC6A8, resulting in mental retardation associated with a complete absence of creatine within the brain and cellular energy perturbation of neuronal cells. One of the therapeutic hypotheses was to administer lipophilic creatine derivatives which are (1) thought to have better permeability through the cell membrane and (2) would not rely on the activity of SLC6A8 to penetrate the brain. Here, we synthesized creatine fatty esters through original organic chemistry process. A screening on an in vitro rat primary cell-based blood-brain barrier model and on a rat primary neuronal cells model demonstrated interesting properties of these prodrugs to incorporate into endothelial, astroglial, and neuronal cells according to a structure-activity relationship. Dodecyl creatine ester showed then a 20-fold increase in creatine content in pathological human fibroblasts compared with the endogenous creatine content, stating that it could be a promising drug candidate.


Asunto(s)
Creatina/química , Creatina/farmacología , Proteínas de Transporte de Membrana/deficiencia , Animales , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Supervivencia Celular/efectos de los fármacos , Técnicas de Química Sintética , Creatina/metabolismo , Creatina/toxicidad , Creatinina/química , Estabilidad de Medicamentos , Ésteres , Femenino , Humanos , Embarazo , Ratas
10.
Biochem Biophys Res Commun ; 417(1): 479-83, 2012 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-22172950

RESUMEN

Chronic kidney disease (CKD) has recently emerged as a major risk factor for cardiovascular pathology. CKD patients display accelerated atherosclerotic process, leading to circulatory complications. However, it is currently not clear how uremic conditions accelerate atherosclerosis. Apoptosis is an important homeostatic regulator of vascular smooth cells under pathological conditions. In the present study, we explored the regulation of apoptosis in cells of the vascular wall in the uremic context. We analysed the expression and regulation of the proteins of the BCL2 family that play an essential role in apoptosis. Our results, obtained in mice and primary human smooth muscle cells exposed to two uremic toxins, point to the existence of an alteration in expression and function of one pro-apoptotic member of this family, the protein BAD. We explore the regulation of BAD by uremic toxins and report the sensitization of vascular smooth muscle cells to apoptosis upon BAD induction.


Asunto(s)
Fallo Renal Crónico/metabolismo , Músculo Liso Vascular/metabolismo , Uremia/metabolismo , Proteína Letal Asociada a bcl/biosíntesis , Animales , Apoptosis , Células Cultivadas , Creatina/metabolismo , Creatina/toxicidad , Humanos , Fallo Renal Crónico/patología , Ratones , Ratones Endogámicos C57BL , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/patología , Urea/metabolismo , Urea/toxicidad , Uremia/patología
11.
Int J Sports Med ; 31(12): 906-12, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21072743

RESUMEN

Airway epithelium plays important roles in the pathophysiology of asthma. Creatine supplementation (Cr) was shown to increase asthma features in a murine model of allergic asthma; however, the role of the airway epithelium in this inflammatory response is not known. BALB/c mice were divided into control, creatine supplementation, ovalbumin-sensitized (OVA) and OVA plus creatine supplementation groups. OVA sensitization occurred on days 0, 14, 28 and 42, and ovalbumin challenge from days 21-53. Cr was also given on days 21-53. Total and differential cells counts in BALF were evaluated. Quantitative epithelial expression of interleukin (IL)-4, IL-5, IL-13, CCL11, CCL5, CCL2, iNOS, VCAM-1, ICAM-1, NF-κB, VEGF, TGF-ß, IGF-1, EGFR, TIMP-1, TIMP-2, MMP-9, MMP-12 and arginase II were performed. Cr increased the number of total cells and eosinophils in BALF, the epithelial content of goblet cells and the epithelial expression of IL-5, CCL2, iNOS, ICAM-1, NF-κB, TGF-ß, TIMP-1 and MMP-9 when compared to the control group (p<0.05). Creatine supplementation also exacerbated goblet cell proliferation, and IL-5 and iNOS expression by epithelial cells compared to the OVA group (p<0.01). Creatine up-regulates the pro-inflammatory cascade and remodelling process in this asthma model by modulating the expression of inflammatory mediators by epithelial cells.


Asunto(s)
Asma/etiología , Creatina/toxicidad , Células Epiteliales/metabolismo , Mediadores de Inflamación/metabolismo , Animales , Asma/fisiopatología , Líquido del Lavado Bronquioalveolar/química , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Células Epiteliales/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Células Caliciformes/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos BALB C , Ovalbúmina , Factores de Tiempo
12.
Int J Sports Med ; 30(9): 684-90, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19569010

RESUMEN

We recently demonstrated that creatine supplementation increased some features of lung allergic sensitization in mice. On the other hand, other studies have shown that aerobic exercise inhibited allergic airway inflammation and remodeling. We hypothesized that aerobic exercise may decrease the exacerbatory effects of the creatine supplementation in a murine model of asthma. Balb/c mice were divided into six groups: Control, Creatine (Cr), Low Intensity Exercise+Creatine (Low+Cr), Ovalbumin (OVA), Ovalbumin+Creatine (OVA+Cr) and Ovalbumin+Creatine+Low Intensity Exercise (OVA+Cr+Low). OVA-sensitized groups were sensitized with OVA intraperitoneal injections (days 0, 14, 28, and 42). Aerosol challenge (OVA 1%) and Cr treatment (0.5 g/kg/day) were initiated on Day 21 until Day 53. Low intensity exercise began on day 22 and was sustained until day 50. Low intensity exercise in the presence of creatine supplementation in sensitized mice resulted in a decreased number of eosinophils in BALF (p<0.001) and in the airways (p<0.001), and a decreased density of inflammatory cells positive to IL-4 (p<0.001) and IL-5 (p<0.001), airway collagen (p<0.001) and elastic fibers (p<0.001) content, airway smooth muscle thickness (p<0.001) and bronchoconstriction index (p<0.05) when compared with OVA+Cr group. These results suggest that aerobic exercise reduces the exacerbatory effects of creatine supplementation in chronically sensitized mice.


Asunto(s)
Asma/prevención & control , Creatina/toxicidad , Condicionamiento Físico Animal/fisiología , Animales , Asma/etiología , Asma/fisiopatología , Líquido del Lavado Bronquioalveolar/inmunología , Broncoconstricción/inmunología , Modelos Animales de Enfermedad , Eosinófilos/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Músculo Liso/metabolismo , Ovalbúmina/inmunología
13.
Rev. bras. med. esporte ; 14(1): 38-41, jan.-fev. 2008. ilus, graf, tab
Artículo en Portugués | LILACS | ID: lil-487433

RESUMEN

A creatina é uma amina nitrogenada e tem sido utilizada principalmente por atletas e praticantes de atividade física que desejam aumentar a massa muscular e o desempenho físico. Entretanto seu uso não está somente relacionado à prática esportiva, pois inúmeros trabalhos apresentam efeitos benéficos na prática médica. Alguns estudos demonstraram que a suplementação oral com creatina resulta em aumento da sua biodisponibilidade plasmática e também de seus estoques em inúmeros órgãos. Entretanto, estudos sobre possíveis efeitos tóxicos da suplementação com creatina são escassos. Portanto, o objetivo deste trabalho foi avaliar os possíveis efeitos tóxicos da suplementação oral com creatina sobre a função e morfologia hepáticas em ratos após 14 dias de suplementação oral com creatina na dose de 0.5 g/kg/dia. A função hepática foi avaliada através de testes bioquímicos e a estrutura hepática foi avaliada através da massa hepática relativa e da análise histológica. Os resultados demonstraram que 14 dias de suplementação com creatina não alteraram a função hepática quando comparado os grupos controle e suplementado: AST (39.5 x 44.4 U/L), ALT (18.6 x 30.8 U/L), ALP (38.5 x 31.4 U/L), GGT (134.8 x 143.8 U/L), proteínas totais (5.1 x 5.5 g/dl), triglicérides (141.0 x 141.0 mg/dl), colesterol total (130.1 x 126.2 mg/dl), colesterol LDL (36.1 x 36.1 mg/dl), colesterol HDL (65.6 x 62.4 mg/dl), colesterol VLDL (25.0 x 28.0 mg/dl), e também estrutura hepática, exceto nos níveis plasmáticos de albumina (3.0 x 3.5 mg/dl - p<0.02). Nossos resultados demonstraram claramente que, ao menos na dose utilizada, a suplementação oral com creatina não induziu a nenhum tipo de efeito tóxico sobre o fígado.


Creatine is a nitrogenated amine and it has been used mainly by athletes and physical activity practitioners who wish to increase muscle mass and performance. However its use is not just related to sports practice, once several studies have shown beneficial effects on medical practice. Some studies have demonstrated that oral creatine supplementation increases its plasmatic bioavailability and also its concentration in several organs. However, studies about the possible toxic effects followed by creatine supplementation are scarce. Therefore, the aim of this work was to evaluate the hepatic structure and function in rats after 14 days of oral creatine supplementation at dose of 0.5g/kg/day. The hepatic function was evaluated through biochemical assays and the hepatic structure was analyzed through the relative hepatic mass and histological analysis. The results showed that 14 days of creatine supplementation did not alter the hepatic function and structure when compared with the control and supplemented groups, AST (39.5 x 44.4 U/L), ALT (18.6 x 30.8 U/L), ALP (38.5 x 31.4 U/L), GGT (134.8 x 143.8 U/L), total proteins (5.1 x 5.5 g/dl), triglycerides (141.0 x 141.0 mg/dl), total cholesterol (130.1 x 126.2 mg/dl), LDL cholesterol (36.1 x 36.1 mg/dl), HDL cholesterol (65.6 x 62.4 mg/dl), VLDL cholesterol (25.0 x 28.0 mg/dl), and also the hepatic structure, except for the albumin plasmatic levels (3.0 x 3.5 mg/dl - p<0.02). Our results clearly demonstrated that, at least at the used dosage, oral creatine supplementation did not induce any toxic effect on the liver.


Asunto(s)
Animales , Masculino , Ratas , Creatina/administración & dosificación , Creatina/toxicidad , Hígado/metabolismo , Ratas Wistar , Suplementos Dietéticos/efectos adversos
14.
Neurology ; 66(5): 664-71, 2006 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-16481597

RESUMEN

BACKGROUND: Creatine and minocycline were prioritized for testing in Phase II clinical trials based on a systematic evaluation of potentially disease modifying compounds for Parkinson disease (PD). OBJECTIVE: To test whether creatine and minocycline alter the course of early PD relative to a predetermined futility threshold for progression of PD in a randomized, double-blind, Phase II futility clinical trial. Agents that do not perform better than the futility threshold are rejected as futile and are not considered for further study. METHODS: Participants had a diagnosis of PD within 5 years, but did not require medications for the management of symptoms. The primary outcome was the change in the total Unified Parkinson's Disease Rating Scale (UPDRS) score from baseline to either the time when there was sufficient disability to warrant symptomatic therapy for PD or 12 months, whichever came first. Subjects were randomized 1:1:1 to receive creatine 10 g/day, minocycline 200 mg/day, or matching placebo. The futility threshold was set as a 30% reduction in UPDRS progression based on the placebo/tocopherol arm of the Deprenyl And Tocopherol Antioxidative Therapy Of Parkinsonism (DATATOP) trial. p values < or = 0.1 indicate futility. RESULTS: Two hundred subjects were randomized to the three groups. Neither creatine (p = 0.96) nor minocycline (p = 0.66) could be rejected as futile based on the DATATOP futility threshold. The rate of progression for the calibration placebo group fell outside the 95% CI for the DATATOP historical control. In a sensitivity analysis, based on the threshold derived from the calibration placebo group, again neither drug could be rejected as futile. Tolerability was 91% in the creatine group and 77% in the minocycline group. Common adverse events included upper respiratory symptoms (26%), joint pain (19%), and nausea (17%). CONCLUSIONS: Both creatine and minocycline should be considered for definitive Phase III trials to determine if they alter the long term progression of Parkinson disease (PD). Additional factors must be weighed before selecting agents for Phase III trials, including safety, tolerability, activity, cost, and availability of these two agents in comparison with other agents currently in development for PD.


Asunto(s)
Creatina/uso terapéutico , Minociclina/uso terapéutico , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/fisiopatología , Anciano , Antibacterianos/uso terapéutico , Antibacterianos/toxicidad , Creatina/toxicidad , Personas con Discapacidad , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Minociclina/toxicidad
15.
Comp Med ; 54(5): 571-7, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15575372

RESUMEN

Although Helicobacter bilis infects mice worldwide, it is not known whether H. bilis causes enterohepatic disease in outbred Swiss Webster (SW) mice. Intestinal and liver specimens from four groups of 39 SW mice, five of which were treated with creatine in the drinking water, were obtained for culture for the presence of H. bilis and were analyzed as to whether infection status was associated with H. bilis seroconversion and/or hepatitis. Helicobacter bilis was isolated from the colon of all 27 mice of groups I-III, but only from the liver of one 12- to 13-month-old female mouse. Ten of 27 livers were H. bilis-positive based on polymerase chain reaction (PCR) analysis; 8 of 10 (80%) of the positive results were for older mice. Results of PCR analysis for H. bilis were negative, and H. bilis was not isolated from 12 control mice (group IV). Irrespective of treatment group or controls, severity of histologic lobular and periportal chronic inflammatory lesions in the liver of H. bilis-infected outbred mice ranged from minimally to moderately severe. Helicobacter bilis infection was associated with increased portal inflammation in group III mice, compared with age-matched, helicobacter-free, group IV mice (P < 0.03). A comparison of potential sex effects in group III mice indicated that H. bilis-infected female mice developed more severe portal inflammation than did H. bilis-infected male mice (P < 0.01). On the basis of results of an ELISA, 8 of 11, 6- to 8-month-old H. bilis-infected mice of group III seroconverted to H. bilis outer membrane antigen. Helicobacter bilis infection is associated with hepatitis in SW mice and can confound experimental results.


Asunto(s)
Infecciones por Helicobacter/microbiología , Helicobacter/patogenicidad , Hepatitis Animal/microbiología , Ciencia de los Animales de Laboratorio , Enfermedades de los Roedores/microbiología , Administración Oral , Animales , Animales no Consanguíneos , Creatina/toxicidad , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Helicobacter/inmunología , Helicobacter/aislamiento & purificación , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/patología , Hepatitis Animal/complicaciones , Hepatitis Animal/patología , Intestinos/efectos de los fármacos , Intestinos/microbiología , Intestinos/patología , Hígado/efectos de los fármacos , Hígado/microbiología , Hígado/patología , Ratones , Enfermedades de los Roedores/patología , Caracteres Sexuales , Abastecimiento de Agua
16.
Am J Physiol Regul Integr Comp Physiol ; 285(4): R762-9, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12959920

RESUMEN

Creatine monohydrate (CrM) supplementation appears to be relatively safe based on data from short-term and intermediate-term human studies and results from several therapeutic trials. The purpose of the current study was to characterize pathological changes after intermediate-term and long-term CrM supplementation in mice [healthy control and SOD1 (G93A) transgenic] and rats (prednisolone and nonprednisolone treated). Histological assessment (18-20 organs/tissues) was performed on G93A mice after 159 days, and in Sprague-Dawley rats after 365 days, of CrM supplementation (2% wt/wt) compared with control feed. Liver histology was also evaluated in CD-1 mice after 300 days of low-dose CrM supplementation (0.025 and 0.05 g x kg-1x day-1) and in Sprague-Dawley rats after 52 days of CrM supplementation (2% wt/wt) with and without prednisolone. Areas of hepatitis were observed in the livers of the CrM-supplemented G93A mice (P < 0.05), with no significant inflammatory lesions in any of the other 18-20 tissues/organs that were evaluated. The CD-1 mice also showed significant hepatic inflammatory lesions (P < 0.05), yet there was no negative effect of CrM on liver histology in the Sprague-Dawley rats after intermediate-term or long-term supplementation nor was inflammation seen in any other tissues/organs (P = not significant). Dietary CrM supplementation can induce inflammatory changes in the liver of mice, but not rats. The observed inflammatory changes in the murine liver must be considered in the evaluation of hepatic metabolism in CrM-supplemented mice. Species differences must be considered in the evaluation of toxicological and physiological studies.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Creatina/toxicidad , Suplementos Dietéticos , Hígado/efectos de los fármacos , Hígado/patología , Animales , Femenino , Masculino , Ratones , Ratones Endogámicos , Ratones Transgénicos , Modelos Animales , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Especificidad de la Especie , Superóxido Dismutasa/genética
18.
Food Chem Toxicol ; 25(10): 747-54, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3679021

RESUMEN

Thirteen commercial meat-flavour samples were analysed for creatine and creatinine content and tested for mutagenicity in the Ames Salmonella/microsome test. In most samples, more than 50% of the creatine had been converted to creatinine. Mutagenicity was related to the creatinine content: 150 mumol creatinine/g dry matter (gdm) gave upwards of 2500 revertants/gdm, concentrations of 15-40 mumol/gdm gave about 100 revertants/gdm and concentrations of 1-10 mumol/gdm gave only low or no significant mutagenicity. No relationship was apparent between coloration and mutagenicity. Beef steaks (initial weight c. 500 g) baked at oven temperatures between 115 and 245 degrees C only showed significant mutagenicity--135 revertants/100 gE (initial raw weight)--in the crust when baked at the highest temperature (245 degrees C). The gravies (meat-juice drip) collected during baking showed a linear increase in mutagenicity with baking temperatures up to 180 degrees C (48-828 revertants/100 gE) and a very sharp increase in mutagenicity for the gravy collected from beef steak baked at 245 degrees C (28,300 revertants/gdm or 19,800 revertants/100 gE). At this high temperature, the brown coloration and the proportion of creatinine to total creatine and creatinine were also dramatically increased, because this gravy dried up completely during the baking procedure.


Asunto(s)
Productos de la Carne/toxicidad , Carne/efectos adversos , Carne/toxicidad , Mutágenos/análisis , Animales , Bovinos , Creatina/toxicidad , Creatinina/toxicidad , Calor , Pruebas de Mutagenicidad , Análisis Espectral
19.
Arzneimittelforschung ; 29(9a): 1449-52, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-395957

RESUMEN

N-Methyl-N-(beta-hydroxyethyl)guanidine O-phosphate (creatinol O-phosphate, COP) has proved to possess anti-ischemic and anti-arrhythmic activities associated with improved ionic balance and heart performance. These activities, which have also been shown in clinical studies, are more evident in pharmacological and clinical conditions involving a hypoxic damage of the heart muscle. Pharmacokinetic studies have shown that absorption of COP administered i.m. is complete. COP is distributed in all organs, and in particular, in the kidney, liver and myocardium. After being dephosphorylated, this drug is eliminated with urine. Dephosphorylation of COP occurs in the kidney and liver. COP crosses the membrane of the myocardial cell, concentrating in the cytosoluble fraction. The results of the toxicological studies confirm that COP has no side effects, is excellently tolerated and has a favourable therapeutic index.


Asunto(s)
Creatina/análogos & derivados , Creatina/farmacología , Animales , Creatina/administración & dosificación , Creatina/toxicidad , Femenino , Fertilidad/efectos de los fármacos , Cobayas , Cinética , Ratones , Embarazo , Conejos , Ratas , Teratógenos
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