Obesity Acarbose a b s t r a c t Ethnopharmacological relevance: Serviceberry or Saskatoon berry ... more Obesity Acarbose a b s t r a c t Ethnopharmacological relevance: Serviceberry or Saskatoon berry [Amelanchier alnifolia (Nutt.) Nutt. ex. M. Roem (Rosaceae)], native to the North Glacier forests of the Rocky Mountains in Montana, has been used by the Blackfeet Indian tribe in alleviation of diabetes. Anecdotally, tea made from twigs and leaves have been used for optimum health and diabetes management. However, such traditional knowledge of the medicinal properties of Amelanchier alnifolia has not been validated by scientific studies. The goal of this study was to identify potential antidiabetic mechanisms of serviceberry. Materials and Methods: Serviceberry plant samples consisting of leaves, twigs, and leaves with berries were extracted and fractionated. Ethyl acetate and water fractions were tested for inhibition of aglucosidase activity in vitro. Diet-induced obese, hyperglycemic C57Bl6 mice were administered serviceberry leaf extract prior to sucrose-, starch-, or glucose-loading to test for a-glucosidase inhibition and decreased post-prandial glycemic response. Results: In the course of screening for potential antidiabetic mechanisms, serviceberry leaf extracts and subfractions demonstrated potent inhibitory activity against mammalian intestinal a-glucosidase activity (EC 3.2.1.20). Further, in an animal model of diet-induced obesity and hyperglycemia, serviceberry leaf subfraction demonstrated significant inhibition of intestinal a-glucosidase activity, and delayed the absorption of carbohydrates, resulting in significant lowering of post-prandial blood glucose concentrations, similar to the antidiabetic drug Acarbose TM . Conclusions: These findings indicating that serviceberry leaf extract may lower post-prandial glycemic response corroborate traditional knowledge of the Blackfeet Indians of Montana, and potentially offer a complementary approach in the treatment of diabetes.
The mapping of V P /V S variations provides an effective tool for lithology discrimination. The u... more The mapping of V P /V S variations provides an effective tool for lithology discrimination. The use of traveltimes from pairs of reflectors on vertical and radial component seismic sections provides a robust and effective means of doing this mapping. The maps provide an effective means to distinguish shales from sandstones in heavy oil fields. Another possible mapping method involves the use of impedance estimation by trace inversions and AVO results. These three mapping techniques provide similar but not identical results. In this paper, we summarize some results of V P /V S mapping for heavy oil fields in Western Canada.
Biochemical and Biophysical Research Communications, 2009
Curcumin, the bioactive component of curry spice turmeric, and its related structures possess pot... more Curcumin, the bioactive component of curry spice turmeric, and its related structures possess potent anti-oxidant and anti-inflammatory properties. Several lines of evidence suggest that curcumin may play a beneficial role in animal models of diabetes, both by lowering blood glucose levels and by ameliorating the long-term complications of diabetes. However, current understanding of the mechanism of curcumin action is rudimentary and is limited to its anti-oxidant and anti-inflammatory effects. In this study we examine potential anti-diabetic mechanisms of curcumin, curcumin C3 complex Ò , and tetrahydrocurcuminoids (THC). Curcuminoids did not exert a direct effect on receptor tyrosine kinase activity, 2-deoxy glucose uptake in L6-GLUT4myc cells, or intestinal glucose metabolism measured by DPP4/a-glucosidase inhibitory activity. We demonstrate that curcuminoids effectively suppressed dexamethasone-induced phosphoenol pyruvate carboxy kinase (PEPCK) and glucose6-phosphatase (G6Pase) in H4IIE rat hepatoma and Hep3B human hepatoma cells. Furthermore, curcuminoids increased the phosphorylation of AMP-activated protein kinase (AMPK) and its downstream target acetyl-CoA carboxylase (ACC) in H4IIE and Hep3B cells with 400 times (curcumin) to 100,000 times (THC) the potency of metformin. These results suggest that AMPK mediated suppression of hepatic gluconeogenesis may be a potential mechanism mediating glucose-lowering effects of curcuminoids.
Publications of the Astronomical Society of Australia, 2012
... Katherine H. KenyonA,B, Arjun ParamasivamA,C, Jiachin TuA,C, Albert ZhangA,D, and Alister W. ... more ... Katherine H. KenyonA,B, Arjun ParamasivamA,C, Jiachin TuA,C, Albert ZhangA,D, and Alister W. GrahamA ... 2001, MNRAS, 322, 486 [11] Batista, PD, Campiteli, MG, Kinouchi, O. 2006, Scientometrics, 68, 179 [12] Blake, C., Brough, S., Couch, W., et al. ...
Biochemical and Biophysical Research Communications, 2009
Curcumin, the bioactive component of curry spice turmeric, and its related structures possess pot... more Curcumin, the bioactive component of curry spice turmeric, and its related structures possess potent anti-oxidant and anti-inflammatory properties. Several lines of evidence suggest that curcumin may play a beneficial role in animal models of diabetes, both by lowering blood glucose levels and by ameliorating the long-term complications of diabetes. However, current understanding of the mechanism of curcumin action is rudimentary and is limited to its anti-oxidant and anti-inflammatory effects. In this study we examine potential anti-diabetic mechanisms of curcumin, curcumin C3 complex Ò , and tetrahydrocurcuminoids (THC). Curcuminoids did not exert a direct effect on receptor tyrosine kinase activity, 2-deoxy glucose uptake in L6-GLUT4myc cells, or intestinal glucose metabolism measured by DPP4/a-glucosidase inhibitory activity. We demonstrate that curcuminoids effectively suppressed dexamethasone-induced phosphoenol pyruvate carboxy kinase (PEPCK) and glucose6-phosphatase (G6Pase) in H4IIE rat hepatoma and Hep3B human hepatoma cells. Furthermore, curcuminoids increased the phosphorylation of AMP-activated protein kinase (AMPK) and its downstream target acetyl-CoA carboxylase (ACC) in H4IIE and Hep3B cells with 400 times (curcumin) to 100,000 times (THC) the potency of metformin. These results suggest that AMPK mediated suppression of hepatic gluconeogenesis may be a potential mechanism mediating glucose-lowering effects of curcuminoids.
Obesity Acarbose a b s t r a c t Ethnopharmacological relevance: Serviceberry or Saskatoon berry ... more Obesity Acarbose a b s t r a c t Ethnopharmacological relevance: Serviceberry or Saskatoon berry [Amelanchier alnifolia (Nutt.) Nutt. ex. M. Roem (Rosaceae)], native to the North Glacier forests of the Rocky Mountains in Montana, has been used by the Blackfeet Indian tribe in alleviation of diabetes. Anecdotally, tea made from twigs and leaves have been used for optimum health and diabetes management. However, such traditional knowledge of the medicinal properties of Amelanchier alnifolia has not been validated by scientific studies. The goal of this study was to identify potential antidiabetic mechanisms of serviceberry. Materials and Methods: Serviceberry plant samples consisting of leaves, twigs, and leaves with berries were extracted and fractionated. Ethyl acetate and water fractions were tested for inhibition of aglucosidase activity in vitro. Diet-induced obese, hyperglycemic C57Bl6 mice were administered serviceberry leaf extract prior to sucrose-, starch-, or glucose-loading to test for a-glucosidase inhibition and decreased post-prandial glycemic response. Results: In the course of screening for potential antidiabetic mechanisms, serviceberry leaf extracts and subfractions demonstrated potent inhibitory activity against mammalian intestinal a-glucosidase activity (EC 3.2.1.20). Further, in an animal model of diet-induced obesity and hyperglycemia, serviceberry leaf subfraction demonstrated significant inhibition of intestinal a-glucosidase activity, and delayed the absorption of carbohydrates, resulting in significant lowering of post-prandial blood glucose concentrations, similar to the antidiabetic drug Acarbose TM . Conclusions: These findings indicating that serviceberry leaf extract may lower post-prandial glycemic response corroborate traditional knowledge of the Blackfeet Indians of Montana, and potentially offer a complementary approach in the treatment of diabetes.
The mapping of V P /V S variations provides an effective tool for lithology discrimination. The u... more The mapping of V P /V S variations provides an effective tool for lithology discrimination. The use of traveltimes from pairs of reflectors on vertical and radial component seismic sections provides a robust and effective means of doing this mapping. The maps provide an effective means to distinguish shales from sandstones in heavy oil fields. Another possible mapping method involves the use of impedance estimation by trace inversions and AVO results. These three mapping techniques provide similar but not identical results. In this paper, we summarize some results of V P /V S mapping for heavy oil fields in Western Canada.
Biochemical and Biophysical Research Communications, 2009
Curcumin, the bioactive component of curry spice turmeric, and its related structures possess pot... more Curcumin, the bioactive component of curry spice turmeric, and its related structures possess potent anti-oxidant and anti-inflammatory properties. Several lines of evidence suggest that curcumin may play a beneficial role in animal models of diabetes, both by lowering blood glucose levels and by ameliorating the long-term complications of diabetes. However, current understanding of the mechanism of curcumin action is rudimentary and is limited to its anti-oxidant and anti-inflammatory effects. In this study we examine potential anti-diabetic mechanisms of curcumin, curcumin C3 complex Ò , and tetrahydrocurcuminoids (THC). Curcuminoids did not exert a direct effect on receptor tyrosine kinase activity, 2-deoxy glucose uptake in L6-GLUT4myc cells, or intestinal glucose metabolism measured by DPP4/a-glucosidase inhibitory activity. We demonstrate that curcuminoids effectively suppressed dexamethasone-induced phosphoenol pyruvate carboxy kinase (PEPCK) and glucose6-phosphatase (G6Pase) in H4IIE rat hepatoma and Hep3B human hepatoma cells. Furthermore, curcuminoids increased the phosphorylation of AMP-activated protein kinase (AMPK) and its downstream target acetyl-CoA carboxylase (ACC) in H4IIE and Hep3B cells with 400 times (curcumin) to 100,000 times (THC) the potency of metformin. These results suggest that AMPK mediated suppression of hepatic gluconeogenesis may be a potential mechanism mediating glucose-lowering effects of curcuminoids.
Publications of the Astronomical Society of Australia, 2012
... Katherine H. KenyonA,B, Arjun ParamasivamA,C, Jiachin TuA,C, Albert ZhangA,D, and Alister W. ... more ... Katherine H. KenyonA,B, Arjun ParamasivamA,C, Jiachin TuA,C, Albert ZhangA,D, and Alister W. GrahamA ... 2001, MNRAS, 322, 486 [11] Batista, PD, Campiteli, MG, Kinouchi, O. 2006, Scientometrics, 68, 179 [12] Blake, C., Brough, S., Couch, W., et al. ...
Biochemical and Biophysical Research Communications, 2009
Curcumin, the bioactive component of curry spice turmeric, and its related structures possess pot... more Curcumin, the bioactive component of curry spice turmeric, and its related structures possess potent anti-oxidant and anti-inflammatory properties. Several lines of evidence suggest that curcumin may play a beneficial role in animal models of diabetes, both by lowering blood glucose levels and by ameliorating the long-term complications of diabetes. However, current understanding of the mechanism of curcumin action is rudimentary and is limited to its anti-oxidant and anti-inflammatory effects. In this study we examine potential anti-diabetic mechanisms of curcumin, curcumin C3 complex Ò , and tetrahydrocurcuminoids (THC). Curcuminoids did not exert a direct effect on receptor tyrosine kinase activity, 2-deoxy glucose uptake in L6-GLUT4myc cells, or intestinal glucose metabolism measured by DPP4/a-glucosidase inhibitory activity. We demonstrate that curcuminoids effectively suppressed dexamethasone-induced phosphoenol pyruvate carboxy kinase (PEPCK) and glucose6-phosphatase (G6Pase) in H4IIE rat hepatoma and Hep3B human hepatoma cells. Furthermore, curcuminoids increased the phosphorylation of AMP-activated protein kinase (AMPK) and its downstream target acetyl-CoA carboxylase (ACC) in H4IIE and Hep3B cells with 400 times (curcumin) to 100,000 times (THC) the potency of metformin. These results suggest that AMPK mediated suppression of hepatic gluconeogenesis may be a potential mechanism mediating glucose-lowering effects of curcuminoids.
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