GlucoMedix ®, an Extract of Stevia Rebaudiana and Uncaria Tomentosa, Reduces Hyperglycemia, Hyperlipidemia, and Hypertension in Rat Models Without Toxicity: A Treatment For Metabolic Syndrome

Background: The objective of this in vivo study is to evaluate in five rat models the pharmacologic effects and toxicity of a commercial hydro-alcoholic extract, GlucoMedix®, derived from Stevia rebaudiana and the pentacyclic chemotype of Uncaria Tomentosa (Willd.) DC, for use as a treatment for Metabolic Syndrome. The extract contains phytochemicals of Stevia (e.g., steviol glycosides) and Uncaria (e.g., pentacyclic oxindole alkaloids, but lacks tetracyclic oxindole alkaloids).Methods: The pharmacologic assessments in three rat models include reductions in chemically induced hyperglycemia, hyperlipidemia (cholesterol and triglycerides), and hypertension, all of which are comorbidities of Metabolic Syndrome. Acute toxicity and 28-day subacute toxicity were assessed in rat models at doses higher than those used in the efficacy models.Results: The acute oral toxicity was evaluated in Holtzman rats and the extract did not produce acute toxic effects or lethality, with the LD50 > 5000 mg/kg (extract wet weight). Furthermore, subacute oral toxicity was evaluated in rats for 28 days at daily doses as high as 2000 mg/kg without toxicity or abnormal clinical chemistry or hematological effects. Daily oral doses of 250 - 1000 mg/kg were used to evaluate the treatment effects in hyperglycemic (alloxan-induced and glibenclamide-controlled), hyperlipidemic (cholesterol-induced and atorvastatin-controlled), and hypertensive (L-NAME-induced and enalapril-controlled) rat models. Alloxan-induced hyperglycemia was reduced in a dose-dependent manner within 28 days or less. Cholesterol-induced hyperlipidemic rats exhibited dose-dependent reductions in cholesterol and triglycerides at 21 days. Furthermore, GlucoMedix® produced a dose-dependent decrease in systolic and diastolic arterial blood pressure in L-NAME-induced hypertensive rats at 28 days.Conclusions: The five in vivo rat models revealed that the all-natural phytotherapy GlucoMedix® is a safe and effective treatment for hyperglycemia, hyperlipidemia, and hypertension. This extract is expected to affect multiple comorbidities of Metabolic Syndrome, without any acute or subacute oral toxicity in humans. Although multiple prescription drugs are well known for the treatment of individual comorbidities of Metabolic Syndrome, no drug monotherapy concurrently treats all three comorbidities.

Uncaria tomentosa (Willd. ex Schult.): focus on nutraceutical aspects

: Medicinal plants have been globally exploiting as an alternative to chemical drugs in the treatment of several diseases due to low unwanted side effects, environmentally friendly nature and low production costs, therefore, it is important to analyze the therapeutic properties of various medicinal plants to understand their potential bioactivity. Uncaria tomentosa is one of these medicinal plants with many health-promoting effects. Although the geographical resources of cat's claw go back to the remote tropics of the Amazon, industrialized countries use the plant extensively in trade. Various parts of the plants such as flowers, leaves, Stem, hook, and seed are mainly used medicinally to treat inflammation, asthma, allergies, skin impurities, microbial infections, neurodegenerative diseases, cancer, cirrhosis, gastrointestinal disorders, arthritis, heart disease, rheumatism, and fever. The end point of this review article is to prospectively scrutinize in vitro and in vivo the therapeutic potential of this plant, especially in terms of its nutritional applications and health beneficial effects.

Manejo y propagación de la uña-de-gato (Uncaria guianensis y U. tomentosa) en comunidades Tikuna del sur de la amazonia colombiana

La uña-de-gato (Uncaria guianensis (Aublet) J.F. Gmel y U. tomentosa (Willd. ex Roemer & Schultes) DC.), empleada en la medicina tradicional amazónica, se destaca por tener propriedades farmacológicas que han generado un interés comercial. Hasta el momento hay una mayor cantidad de estudios sobre el manejo agroforestal y los métodos de propagación de la U. tomentosa; no obstante, es poca la información disponible sobre la Uncaria guianensis, en especial con lo relacionado a su manejo en comunidades. Con el propósito de contribuir con información sobre el manejo de estas especies y de evaluar su propagación vegetativa, se realizaron entrevistas, recorridos de campo y ensayos de siembra en comunidades Tikuna. Se encontró que el manejo de las especies de uña-de-gato, principalmente de la Uncaria guianensis, se centra tanto en las prácticas de extracción y siembra por estacas, así como en su regeneración natural. Igualmente, en los experimentos de propagación vegetativa se evidenció que la Uncaria tomentosa presentó una alta tasa de mortalidad, pues fue más susceptible a los efectos de las condiciones ambientales. Por el contrario, la Uncaria guianensis tuvo una mayor tasa de sobrevivencia, especialmente en bosques secundarios donde se sembraron estacas tratadas con hormonas de enraizameinto y en suelos enriquecidos con abono orgánico. Los resultados obtenidos en este estudio pueden contribuir en la formulación de estrategias de manejo integral, que permitan un uso sostenible de poblaciones naturales de las especies de uña-de-gato en comunidades amazónicas.

Changes in Human Erythrocyte Membrane Exposed to Aqueous and Ethanolic Extracts from Uncaria tomentosa

Uncaria tomentosa (Willd.) DC is a woody climber species originating from South and Central America that has been used in the therapy of asthma, rheumatism, hypertension, and blood purification. Our previous study showed that U. tomentosa extracts altered human erythrocyte shape, which could be due to incorporation of the compounds contained in extracts into the erythrocyte membrane. The aim of the present study was to determine how the compounds contained in U. tomentosa extracts incorporate into the human erythrocyte membrane. The study has assessed the effect of aqueous and ethanolic extracts from leaves and bark of U. tomentosa on the osmotic resistance of the human erythrocyte, the viscosity of erythrocyte interior, and the fluidity of erythrocyte plasma membrane. Human erythrocytes were incubated with the studied extracts in the concentrations of 100, 250, and 500 µg/mL for 2, 5, and 24 h. All extracts tested caused a decrease in erythrocyte membrane fluidity and increased erythrocyte osmotic sensitivity. The ethanolic extracts from the bark and leaves increased viscosity of the erythrocytes. The largest changes in the studied parameters were observed in the cells incubated with bark ethanolic extract. We consider that the compounds from U. tomentosa extracts mainly build into the outer, hydrophilic monolayer of the erythrocyte membrane, thus protecting the erythrocytes against the adverse effects of oxidative stress.