Gastrodia elata Blume Rhizome Aqueous Extract Improves Arterial Thrombosis, Dyslipidemia, and Insulin Response in Testosterone-Deficient Rats.

Testosterone deficiency deteriorates glucose and lipid metabolism with reducing muscle mass. We investigated whether the consumption of water extracts of Gastrodia elata Blume rhizome (GEB) rich in gastrodin would reduce the symptoms of testosterone deficiency and improve blood flow in orchidectomized (ORX) rats. ORX rats were given high-fat diets supplemented with either 1% cellulose (ORX-control), 0.3% GEB (GEB-L), or 1% GEB (GEB-H) for 8 weeks. Sham-operated rats were fed the same diet as OVX-control rats (normal-control). ORX-control rats had reduced serum testosterone levels by one-fifth, compared to normal-control rats. ORX-control rats exhibited decreased lean body mass, attenuated blood flow, and impaired cholesterol metabolism and glucose control due to decreased insulin secretory response. GEB increased serum insulin levels dose-dependently and GEB-H mostly enhanced dyslipidemia in ORX rats. GEB completely normalized arterial thrombosis time and blood flow in ORX rats. Interestingly, ORX-control rats showed attenuated hepatic insulin signaling but greater AMPK and CREB activities, which reduced triglyceride accumulation, compared to normal-control. GEB-H improved hepatic insulin signaling but maintained the AMPK and CREB activities in ORX rats. In conclusions, GEB ameliorated the impairment of cholesterol and glucose metabolism and blood flow in ORX rats. GEB may be a potential preventive measure for reducing the risk of cardiovascular diseases associated with testosterone deficiency.

The combination of Artemisia princeps Pamp, Leonurus japonicas Houtt, and Gardenia jasminoides Ellis fruit attenuates the exacerbation of energy, lipid, and glucose by increasing hepatic PGC-1α expression in estrogen-deficient rats.

BACKGROUND: Artemisia princeps Pamp (APP), Leonurus japonicas Houtt (LJH), and Gardenia jasminoides Ellis fruit (GJE) have been traditionally used in East Asia to treat women's diseases related to reproductive system. They may attenuate the deterioration of energy, lipid, glucose and bone metabolism by estrogen deficiency. The present study explored the combination of APP, LJH, and GJE to overcome the symptoms of estrogen deficiency and the mechanism was explored. METHODS: Ovariectomized (OVX) rats were divided into five groups and fed high-fat diets supplemented with 2 % dextrin (control), 2 % APP, 2 % APP + LJH (15:5), APP + LJH + GJE (10:5:5) or 17ß-estradiol (30 µg/kg bw/day) for 8 weeks. After 8 weeks of their consumption, energy, lipid, glucose and bone metabolisms were investigated and hepatic insulin signaling and fatty acid metabolism were determined. RESULTS: APP + LJH + GJE, but not APP itself, improved energy metabolism and attenuated a decrease in energy expenditure by the same amount as estrogen. Moreover, APP + LJH + GJE reduced visceral fat and intramuscular fat and increased lean body mass measured by DEXA by as much as the positive-control. APP itself suppressed increased LDL cholesterol and triglyceride levels in OVX rats and APP + LJH + GJE alleviated dyslipidemia in OVX rats. Overnight-fasted serum insulin levels and HOMA-IR were reduced in the descending order of APP, APP + LJH, APP + LJH + GJE, positive-control in OVX rats. APP and APP + LJH elevated insulin secretion in the 1st part of OGTT to decrease serum glucose levels while APP + LJH + GJE reduced serum glucose levels without increasing serum insulin levels during OGTT. APP + LJH + GJE decreased insulin resistance during ITT in OVX rats more than the positive-control. The APP + LJH + GJE group exhibited increased hepatic peroxisomal proliferator-activated receptor-γ coactivator-1α expression, which increased the number of genes involved in fatty acid oxidation and decreased fatty acid synthesis. Hepatic insulin signaling (pAkt and pGSK-1ß) was also potentiated to reduce phosphoenolpyruvate carboxykinase proteins. CONCLUSION: The combination of APP + LJH + GJE attenuated various menopausal symptoms in OVX rats. Thus, it may have potential as a therapeutic agent for the treatment of postmenopausal symptoms.

A 70% Ethanol Extract of Mistletoe Rich in Betulin, Betulinic Acid, and Oleanolic Acid Potentiated ß-Cell Function and Mass and Enhanced Hepatic Insulin Sensitivity.

We investigated that the long-term consumption of the water (KME-W) and 70% ethanol (KME-E) mistletoe extracts had antidiabetic activities in partial pancreatectomized (Px) rats. Px rats were provided with a high-fat diet containing 0.6% KME-E, 0.6% KME-W, and 0.6% dextrin (control) for 8 weeks. As normal-control, Sham-operated rats were provided with 0.6% dextrin. In cell-based studies, the effects of its main terpenoids (betulin, betulinic acid, and oleanolic acid) on glucose metabolism were measured. Both KME-W and KME-E decreased epididymal fat mass by increasing fat oxidation in diabetic rats. KME-E but not KME-W exhibited greater potentiation of first-phase insulin secretion than the Px-control in a hyperglycemic clamp. KME-E also made ß-cell mass greater than the control by increasing ß-cell proliferation and decreasing its apoptosis. In a euglycemic-hyperinsulinemic clamp, whole-body glucose infusion rate and hepatic glucose output increased with potentiating hepatic insulin signaling in the following order: Px-control, KME-W, KME-E, and normal-control. Betulin potentiated insulin-stimulated glucose uptake via increased PPAR-γ activity and insulin signaling in 3T3-L1 adipocytes, whereas oleanolic acid enhanced glucose-stimulated insulin secretion and cell proliferation in insulinoma cells. In conclusion, KME-E prevented the deterioration of glucose metabolism in diabetic rats more effectively than KME-W and KME-E can be a better therapeutic agent for type 2 diabetes than KME-W.