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1.
J Am Coll Nutr ; 35(2): 100-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26885762

RESUMEN

OBJECTIVE: Nitrate-rich (NR) supplements can enhance exercise performance by improving neuromuscular function and the aerobic cost of exercise. However, little is known about the effects of nitrate on dynamic, multijoint resistance exercise. METHODS: Fourteen resistance-trained men (age, 21.1 ± 0.9 years; height, 173.2 ± 2.9 cm: body mass, 77.6 ± 4.3 kg; squat one-repetition maximum [1RM], 127.5 ± 18.8 kg) participated in a randomized, double-blind, crossover experiment. Subjects consumed an NR or nitrate-poor (NP) supplement for 3 days, performed a bout of heavy resistance exercise, completed a washout, and then repeated the procedures with the remaining supplement. Before, during, and after exercise, individual and gross motor unit efficiency was assessed during isometric and dynamic muscle contractions. In addition, we compared physical performance, heart rate, lactate, and oxygen consumption (VO2). RESULTS: Nitrate-rich supplementation resulted in lower initial muscle firing rates at rest and lower mean and maximum firing rates over the course of fatiguing exercise. Nitrate-poor supplementation was accompanied by increased mean and maximum firing rates by the end of exercise and lower initial firing rates. In addition, NR supplementation resulted in higher mean peak electromyography (EMG) amplitudes. Heart rate, lactate, and physical performance did not differ by treatment, but oxygen consumption increased more frequently when the NP supplement was consumed. CONCLUSION: Supplementation with an NR beetroot extract-based supplement provided neuromuscular advantages during metabolically taxing resistance exercise.


Asunto(s)
Suplementos Dietéticos/análisis , Ejercicio Físico/fisiología , Nitratos/farmacología , Reclutamiento Neurofisiológico/efectos de los fármacos , Beta vulgaris/química , Método Doble Ciego , Humanos , Masculino , Nitratos/administración & dosificación , Nitratos/química , Raíces de Plantas/química , Adulto Joven
2.
J Transl Med ; 6: 3, 2008 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-18205911

RESUMEN

BACKGROUND: We examined the therapeutic potential of a proprietary Croton palanostigma extract (Zangrado(R)) in the management of emesis and itch. METHODS: Emesis was induced in ferrets with morphine-6-glucuronide (0.05 mg/kg sc) in the presence of Zangrado (3 mg/kg, ip) and the cannabinoid receptor 1 antagonist, AM 251 (5 mg/kg, ip). Topical Zangrado (1%) was assessed for anti-pruretic actions in the 5-HT-induced scratching model in rats and evaluated in capsaicin-induced gastric hyperemia as measured by laser doppler flow. In the ApcMinmouse model of precancerous adenomatosis polyposis, mice received Zangrado (100 mug/ml in drinking water) from the age of 6 - 16 weeks for effects on polyp number. In RAW 264.7 cells Zangrado was examined for effects on lipopolysaccharide-induced nitrite production. RESULTS: Zangrado was a highly effective anti-emetic, reducing morphine-induced vomiting and retching by 77%. These benefits were not associated with sedation or hypothermia and were not reversed by cannabinoid receptor antagonism. Itch responses were blocked in both the morphine and 5-HT models. Zangrado did not exacerbate the ApcMincondition rather health was improved. Capsaicin-induced hyperemia was blocked by Zangrado, which also attenuated the production of nitric oxide by activated macrophages. CONCLUSION: Zangrado is an effective anti-emetic and anti-itch therapy that is devoid of common side-effects, cannabinoid-independent and broadly suppresses sensory afferent nerve activation. This complementary medicine represents a promising new approach to the management of nausea, itch and irritable bowel syndrome.


Asunto(s)
Antieméticos/uso terapéutico , Antipruriginosos/uso terapéutico , Extractos Vegetales/uso terapéutico , Proantocianidinas/uso terapéutico , Prurito/tratamiento farmacológico , Receptor Cannabinoide CB1/antagonistas & inhibidores , Vómitos/tratamiento farmacológico , Animales , Línea Celular , Croton , Hurones , Masculino , Ratones , Ratones Endogámicos C57BL , Derivados de la Morfina/administración & dosificación , Náusea/tratamiento farmacológico , Piperidinas , Prurito/inducido químicamente , Pirazoles , Ratas , Ratas Sprague-Dawley , Vómitos/inducido químicamente
4.
BMC Complement Altern Med ; 7: 34, 2007 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-17974032

RESUMEN

BACKGROUND: The efficacy and safety of a dietary supplement derived from South American botanicals was compared to glucosamine sulfate in osteoarthritis subjects in a Mumbai-based multi-center, randomized, double-blind study. METHODS: Subjects (n = 95) were screened and randomized to receive glucosamine sulfate (n = 47, 1500 mg/day) or reparagen (n = 48, 1800 mg/day), a polyherbal consisting of 300 mg of vincaria (Uncaria guianensis) and 1500 mg of RNI 249 (Lepidium meyenii) administered orally, twice daily. Primary efficacy variable was response rate based on a 20% improvement in WOMAC pain scores. Additional outcomes were WOMAC scores for pain, stiffness and function, visual analog score (VAS) for pain, with assessments at 1, 2, 4, 6 and 8 weeks. Tolerability, investigator and subject global assessments and rescue medication consumption (paracetamol) were measured together with safety assessments including vital signs and laboratory based assays. RESULTS: Subject randomization was effective: age, gender and disease status distribution was similar in both groups. The response rates (20% reduction in WOMAC pain) were substantial for both glucosamine (89%) and reparagen (94%) and supported by investigator and subject assessments. Using related criteria response rates to reparagen were favorable when compared to glucosamine. Compared to baseline both treatments showed significant benefits in WOMAC and VAS outcomes within one week (P < 0.05), with a similar, progressive improvement over the course of the 8 week treatment protocol (45-62% reduction in WOMAC or VAS scores). Tolerability was excellent, no serious adverse events were noted and safety parameters were unchanged. Rescue medication use was significantly lower in the reparagen group (p < 0.01) at each assessment period. Serum IGF-1 levels were unaltered by treatments. CONCLUSION: Both reparagen and glucosamine sulfate produced substantial improvements in pain, stiffness and function in subjects with osteoarthritis. Response rates were high and the safety profile was excellent, with significantly less rescue medication use with reparagen. Reparagen represents a new natural productive alternative in the management of joint health. TRIAL REGISTRATION: Current Controlled Trials ISRCTN25438351.


Asunto(s)
Glucosamina/uso terapéutico , Osteoartritis de la Rodilla/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Acetaminofén/administración & dosificación , Método Doble Ciego , Femenino , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/sangre , Osteoartritis de la Rodilla/complicaciones , Dolor/etiología , Dolor/prevención & control , Dimensión del Dolor , Resultado del Tratamiento
5.
BMC Complement Altern Med ; 6: 13, 2006 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-16603065

RESUMEN

BACKGROUND: Cartilage loss is a hallmark of arthritis and follows activation of catabolic processes concomitant with a disruption of anabolic pathways like insulin-like growth factor 1 (IGF-1). We hypothesized that two natural products of South American origin, would limit cartilage degradation by respectively suppressing catabolism and activating local IGF-1 anabolic pathways. One extract, derived from cat's claw (Uncaria guianensis, vincaria), is a well-described inhibitor of NF-kappaB. The other extract, derived from the vegetable Lepidium meyenii (RNI 249), possessed an uncertain mechanism of action but with defined ethnomedical applications for fertility and vitality. METHODS: Human cartilage samples were procured from surgical specimens with consent, and were evaluated either as explants or as primary chondrocytes prepared after enzymatic digestion of cartilage matrix. Assessments included IGF-1 gene expression, IGF-1 production (ELISA), cartilage matrix degradation and nitric oxide (NO) production, under basal conditions and in the presence of IL-1beta. RESULTS: RNI 249 enhanced basal IGF-1 mRNA levels in human chondrocytes by 2.7 fold, an effect that was further enhanced to 3.8 fold by co-administration with vincaria. Enhanced basal IGF-1 production by RNI 249 alone and together with vincaria, was confirmed in both explants and in primary chondrocytes (P < 0.05). As expected, IL-1beta exposure completely silenced IGF-1 production by chondrocytes. However, in the presence of IL-1beta both RNI 249 and vincaria protected IGF-1 production in an additive manner (P < 0.01) with the combination restoring chondrocyte IGF-1 production to normal levels. Cartilage NO production was dramatically enhanced by IL-1beta. Both vincaria and RNI 249 partially attenuated NO production in an additive manner (p < 0.05). IL-1beta - induced degradation of cartilage matrix was quantified as glycosaminoglycan release. Individually RNI 249 or vincaria, prevented this catabolic action of IL-1beta. CONCLUSION: The identification of agents that activate the autocrine production of IGF-1 in cartilage, even in the face of suppressive pro-inflammatory, catabolic cytokines like IL-1beta, represents a novel therapeutic approach to cartilage biology. Chondroprotection associated with prevention of the catabolic events and the potential for sustained anabolic activity with this natural product suggests that it holds significant promise in the treatment of debilitating joint diseases.


Asunto(s)
Condrocitos/efectos de los fármacos , Condrocitos/metabolismo , Factor I del Crecimiento Similar a la Insulina/biosíntesis , Interleucina-1/metabolismo , Lepidium , Fragmentos de Péptidos/metabolismo , Extractos Vegetales/farmacología , Uncaria , Células Cultivadas/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Expresión Génica/efectos de los fármacos , Glicosaminoglicanos/metabolismo , Humanos , Factor I del Crecimiento Similar a la Insulina/genética , Interleucina-1beta , Óxido Nítrico/biosíntesis , Proteínas Recombinantes
6.
BMC Cancer ; 2: 19, 2002 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-12171603

RESUMEN

BACKGROUND: In recent years it has become evident that nonsteroidal anti-inflammatory drugs, in particular aspirin represent a potential class of cancer chemotherapeutic agents. Despite the wealth of knowledge gained from epidemiological, clinical and animal studies, the effectiveness of aspirin to treat established gastrointestinal cancer has not been determined. The present study examines the ability of aspirin to treat established polyposis in Min/+ mice. METHODS: Min/+ mice with established polyposis were treated orally once daily from 12-16 weeks of age with either drug vehicle or aspirin (25 mg/kg). Upon completion of treatment, the number, location and size of intestinal tumours was determined. Additional variables examined were the number of apoptotic cells within tumours and COX activity. RESULTS: Administration of aspirin for 4 weeks to Min/+ mice produce no effect on tumour number compared to vehicle-treated Min/+ mice (65 +/- 8 vs. 63 +/- 9, respectively). In addition, aspirin had no effect on tumour size or location. However, aspirin treatment produced a greater than 2-fold (p<0.05) increase in the number of apoptotic positive cells within tumours and significantly decreased hepatic PGE2 content. CONCLUSIONS: Aspirin was found to have no effect on tumour number and size when administered to Min/+ mice with established polyposis. The findings in the present study call in to question the utility of aspirin as a stand-alone treatment for established GI cancer. However, aspirin's ability to significantly promote apoptosis may render it suitable for use in combinatorial chemotherapy.


Asunto(s)
Poliposis Adenomatosa del Colon/tratamiento farmacológico , Antiinflamatorios no Esteroideos/uso terapéutico , Antineoplásicos/uso terapéutico , Aspirina/uso terapéutico , Poliposis Adenomatosa del Colon/enzimología , Poliposis Adenomatosa del Colon/patología , Animales , Apoptosis , Genes APC , Ratones , Ratones Endogámicos C57BL , Prostaglandina-Endoperóxido Sintasas/metabolismo
7.
J Ethnopharmacol ; 80(2-3): 121-9, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12007701

RESUMEN

Sangre de grado is an ethnomedicinal red tree sap obtained from Croton spp. that is used to treat gastrointestinal ulcers, cancer and to promote wound healing. To evaluate the potential role of sangre de grado (SdG) in cancer we examined its effects on human cancer cells, AGS (stomach), HT29 and T84 (colon). Viability of cells treated with SdG (10-200 microg/ml) decreased (P<0.01) in a dose dependent manner measured over a 24-h period. Cell proliferation at 48 h decreased (P<0.01) in all cells treated with SdG (>100 microg/ml). When cells in suspension were treated with SdG (100 microg/ml) cell adherence was severely compromised (>85%). Cells treated with SdG (100 microg/ml) underwent apoptosis as detected by nucleus condensation and DNA fragmentation determined by ELISA, and flow cytometry. Morphological changes as assessed by acridine orange. These effects were similar to that observed with Taxol (30 microM). A significant alteration of microtubular architecture was equally observed in both stomach and colon cancer cells exposed to SdG (100 microg/ml). The induction of apoptosis and microtubule damage in AGS, HT29 and T84 cells suggest that sangre de grado should be evaluated further as a potential source of anti-cancer agents.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis , Croton , Extractos Vegetales/farmacología , Adhesión Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Neoplasias Gastrointestinales , Humanos , Microscopía Fluorescente , Microtúbulos/efectos de los fármacos , Microtúbulos/ultraestructura , Células Tumorales Cultivadas
8.
Food Chem Toxicol ; 63: 240-3, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24262485

RESUMEN

A case study is reported whereby an individual with known sulfite and sulfonamide allergies develops hypersensitivity to taurine above a threshold level as well as to the non-nutritive sweetener acesulfame potassium, compounds that are not normally associated with allergic reactions. Sulfites, sulfonamides, taurine and acesulfame potassium all contain a SO3 moiety. Challenge tests provide evidence for the hypersensitivities to taurine and acesulfame potassium. The subject is also allergic to thiuram mix and thimerosal, sulfur containing compounds, as well as to various food products. This may be the first case where hypersensitivities to taurine and acesulfame potassium have been documented and reported. Several mechanistic explanations are provided for the untoward reactions to taurine and acesulfame potassium.


Asunto(s)
Hipersensibilidad a las Drogas , Azufre/efectos adversos , Adulto , Femenino , Humanos , Sulfitos/efectos adversos , Sulfitos/química , Sulfonamidas/efectos adversos , Sulfonamidas/química , Taurina/efectos adversos , Taurina/química , Tiazinas/efectos adversos , Tiazinas/química
9.
J Inflamm (Lond) ; 2: 11, 2005 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-16242032

RESUMEN

BACKGROUND: This study was designed to determine if a natural mineral supplement, sierrasil, alone and in combination with a cat's claw extract (Uncaria guianensis), vincaria, has therapeutic potential in mild to moderate osteoarthritis of the knee. METHODS: Patients (n = 107) with mild to moderate osteoarthritis of the knee were randomly assigned to one of 4 groups; high dose sierrasil (3 g/day), low dose sierrasil (2 g/day), low dose sierrasil (2 g/day) + cat's claw extract (100 mg/day) or placebo, administered for 8 weeks. Treatment was double blinded. Primary efficacy variables were WOMAC scores (A, B, C and total). Visual analog score (VAS) for pain, consumption of rescue medication (paracetamol), and tolerability were secondary variables. Safety measures included vital signs and laboratory-based assays. RESULTS: Ninety-one of the 107 patients successfully completed the protocol. All four groups showed improvement in WOMAC and VAS scores after 8 weeks (p < 0.001), in all 3 groups receiving sierrasil the magnitude of benefits were greater vs. placebo (WOMAC Total 38-43% vs. 27%) but this was not statistically significant. In reference to baseline values sierrasil treated groups had a considerably faster onset of benefits. Placebo-treated individuals failed to show significant benefits at 4 weeks (11% reduction in total WOMAC). In contrast, after 1 or 2 weeks of therapy all the sierrasil groups displayed significant reductions in WOMAC scores (p < 0.05) and at week 4 displayed a 38-43% improvement. VAS was significantly improved at 4 weeks in all groups (p < 0.001) but was significantly greater in all sierrasil groups compared to placebo (p < 0.05). Rescue medication use was 28-23% lower in the herbomineral combination and high dose sierrasil groups although not statistically different from placebo (P = 0.101 and P = 0.193, respectively). Tolerability was good for all groups, no serious adverse events were noted and safety parameters remained unchanged. CONCLUSION: The natural mineral supplement, sierrasil alone and in combination with a cat's claw extract, improved joint health and function within 1-2 weeks of treatment but significant benefits over placebo were not sustained, possibly due to rescue medication masking. Sierrasil may offer an alternative therapy in subjects with joint pain and dysfunction.

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