Acteoside Isolated from Colebrookea oppositifolia Smith Attenuates Epilepsy in Mice Via Modulation of Gamma-Aminobutyric Acid Pathways.

The present study was aimed to evaluate the anticonvulsant activity of acteoside and explore its mechanism of action. Initially, the acteoside was evaluated in maximal electroshock (MES) and pentylenetetrazole (PTZ)-induced convulsions, and later it was evaluated against N-methyl-D-aspartic acid (NMDA)-induced mortality in Swiss albino mice. Based on the response in these models, further evaluations were performed to explore the mechanism of action. In the results, the acteoside (10, 25, and 50 mg/kg) has shown significant anticonvulsant activity in the PTZ model (p < 0.01 for all doses); however, there was no protection observed in MES and NMDA models. Therefore, further mechanism-based studies were performed on the PTZ model, and the outcomes have revealed that there was a significant reduction in GABA (p < 0.01 for both regions) and elevation of glutamate (p < 0.01 for both regions) in the cortex and hippocampus regions of PTZ-treated animals. Further, the antioxidant levels (SOD, catalase, GPx, GR, GSH, LPO) were altered significantly (p < 0.01 for all parameters), with reduced GABAA mRNA levels (p < 0.01) in the PTZ control compared with the normal control. Interestingly, co-administration of acteoside (25 mg/kg) (p < 0.01 for all parameters) has restored all the PTZ-induced alterations compared to PTZ-control. Moreover, the anti-PTZ action of acteoside was completely blocked in the presence of flumazenil, and thus confirmed the GABAergic mechanism behind the anticonvulsant activity of acteoside. Besides, actophotometer and rotarod tests have confirmed that the acteoside is free from central side effects like motor incoordination and locomotor deficits.

Achyranthes aspera Linn. alleviates cerebral ischemia-reperfusion-induced neurocognitive, biochemical, morphological and histological alterations in Wistar rats.

ETHNOPHARMACOLOGICAL RELEVANCE: In the traditional system of Indian medicine, the whole plant and roots of Achyranthes aspera L have been extensively used to treat neurological conditions such as epilepsy and stroke by the various ethnic communities of India. AIM OF THE STUDY: The present study was aimed to evaluate the cerebroprotective potential of methanol extract of A. aspera aerial parts (MeAA). MATERIALS AND METHODS: Initially the MeAA was evaluated for total phenolic content and subjected to detailed liquid chromatography-mass spectrometry analysis. Additionally, it was evaluated for in vitro antioxidant activity in ferric reducing antioxidant power, 2, 2-diphenyl-1-picrylhydrazyl and oxygen radical absorbance capacity assays. Furthermore, in RAW 264.7 cell lines the effect of MeAA was evaluated on lipopolysaccharide-induced generation of reactive oxygen species, nitrite and tumor necrosis factor-α. Finally, the MeAA (400 and 800 mg/kg) was evaluated against ischemia-reperfusion (I/R)-induced brain injury in rats. In brief, male Wistar rats were allocated in to five groups (G-I to G-V, n = 10). G-I and G-II assigned as sham control and I/R control, and received only vehicle (carboxy methyl cellulose 0.5% w/v, 10 ml/kg, p.o.). G-III received quercetin (20 mg/kg, p.o.) and assigned as reference standard. G-IV and G-V group animals received 400 and 800 mg/kg oral doses of MeAA, respectively. All the treatments were given orally for a period of seven days and the parameters such as functional (neurological, cognitive and motor), morphological (edema and infarct area), biochemical (superoxide dismutase, catalase, reduced glutathione, lipid peroxidation, cytokines), and histopathological evaluations of the brain tissue was performed. RESULTS: The MeAA exhibited 72.48 mg gallic acid equivalents/g of total phenolic content and the LC-MS/MS analysis showed acteoside, apigenin, and pentagalloyl glucose as major ingredients in the MeAA. In in vitro antioxidant assays, the MeAA showed good antioxidant activity with IC50 of 126.50 µg/ml in DPPH assay; FRAP and ORAC values of 759.65 and 979.4 in FRAP and ORAC assays, respectively. Further, the MeAA significantly suppressed the generation of ROS, nitrite and TNF-α in LPS activated RAW 264.7 cell lines. Besides, sixty mins of global cerebral ischemia followed by 24 h of reperfusion produced considerable alterations in neurobehavioral functions in the I/R control group compared to sham control, with a significant reduction in catalase and superoxide dismutase enzyme activities. Moreover, there was a significant reduction in reduced glutathione levels with increased lipid peroxidation. Furthermore, the levels of pro-inflammatory cytokines (TNF-α, IL-6, and ICAM-I) increased significantly and those of anti-inflammatory (IL-10) decreased. I/R insult increased the brain volume and aggravated cerebral infarct formation. Histopathological examination of the brain tissue revealed vascular congestion, cerebral edema, leukocyte infiltration, and brain tissue necrosis. Interestingly, seven days pretreatment with MeAA (800 mg/kg, p.o.) has offered significant protection against I/R-induced functional, morphological, biochemical and histopathological alterations in Wistar rats. CONCLUSIONS: These findings suggest that the MeAA possesses potent cerebroprotective action through its antioxidant and anti-inflammatory mechanisms.

Momordica cymbalaria fruit extract attenuates high-fat diet-induced obesity and diabetes in C57BL/6 mice.

OBJECTIVES: The present study was aimed to evaluate the effect of methanolic fruit extract of Momordica cymbalaria (MeMC) against high-fat diet-induced obesity and diabetes in C57BL/6 mice. MATERIALS AND METHODS: In the present study, six weeks old male C57BL/6 mice were divided into four groups. G-1 and G-2 served as lean control and HFD control, G-3 and G-4 received MeMC 25 and 50 mg/kg, BW doses; all the treatments were given for a period of 11 weeks. The parameters such as body weight, fasting blood glucose, insulin, cholesterol, free fatty acid, and oral glucose tolerance tests were performed, further, at the end of the study fasting body weight, and weights of organs such as the liver, heart, and adipose tissue were measured and the liver tissue was subjected to histopathology evaluation, and insulin resistance was expressed as HOMA-IR index. RESULTS: The high-fat diet fed C57 mice showed significant elevation of body weight (P<0.01), blood glucose (P<0.01), insulin (P<0.01), cholesterol (P<0.01), free fatty acid (P<0.01), and HOMA-IR index (P<0.01) along with significant elevation of all organ weights and reduction in oral glucose tolerance (P<0.01) and brown adipose weight (P<0.01). The histopathology showed significant fatty infiltration and hypertrophy of hepatocytes. Interestingly, MeMC (50 mg/kg) alleviated all the HFD-induced perturbances significantly. Further, the HPLC analysis of MeMC revealed the presence of gallic acid and rutin as chief ingredients. CONCLUSION: MeMC possesses potent antidiabetic activity and ameliorates insulin resistance in HFD diet fed C57 mice.

Chemical characterization and cerebroprotective effect of methanolic root extract of Colebrookea oppositifolia in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Colebrookea oppositifolia Smith is one of the extensively used plants to treat neurological conditions such as epilepsy by the various ethnic communities in sub-Himalayan regions of India such as Bhoxa, Tharu and nomadic Gujjars. AIM OF THE STUDY: This study was conducted to evaluate the cerebroprotective effect of C. oppositifolia methanolic root (MeCO) extract in Wistar rats. MATERIALS AND METHODS: The MeCO was characterized for total phenolic content and later subjected for detailed liquid chromatography-mass spectrometry analysis. Further, it was evaluated for in vitro antioxidant activity using 2, 2-diphenyl-1-picrylhydrazyl, ferric reducing antioxidant power and oxygen radical absorbance capacity assays. In addition, the MeCO was investigated on generation of ROS, nitrite, and TNF-α in LPS-stimulated RAW 264.7 cell lines. Finally, the cerebroprotective effect of MeCO was examined against global ischemia and reperfusion (I/R)-induced brain injury in Wistar rats. Male Wistar rats were allocated in to five groups (G-I to G-V, n = 10). G-I and G-II served as sham control and I/R control, respectively, and received only vehicle (0.5% w/v carboxy methyl cellulose, 10 ml/kg, p.o.). G-III served as reference standard and received quercetin (20 mg/kg, p.o.). G-IV and G-V animals received 200 and 400 mg/kg oral doses of MeCO, respectively. All the treatments were given for a period of seven days and the parameters such as neurobehavioral (neurological, and cognitive), and motor functions, biochemical (enzymatic and non-enzymatic antioxidants, TNF-α, IL-6, IL-10, ICAM-I), morphological (cerebral edema and infarct area) and histopathological evaluations were performed. RESULTS: The MeCO showed a total phenolic content of 137.28 mg gallic acid equivalents/g, and LC-MS/MS analysis of MeCO showed presence of acteoside, gossypin, quercetin and ferulic acid as major ingredients (6680.3, 1.55, 3.52 and 431.1 ng/mg). In in vitro antioxidant assays, the MeCO exhibited potent activity with IC50 of 49.10 µg/ml in DPPH assay; FRAP and ORAC values of 1180.5 and 2983.5 respectively. Furthermore, the MeCO significantly inhibited generation of ROS, nitrite and TNF-α in LPS-stimulated RAW 264.7 cell lines. Sixty min of global ischemia with 24 h reperfusion produced substantial alterations in neurobehavioral functions in the I/R control group compared to sham control. In addition, a significant reduction in catalase and superoxide dismutase activities was observed. Moreover, lipid peroxidation increased and reduced glutathione levels decreased significantly. Furthermore, the levels of pro-inflammatory cytokines (TNF-α, IL-6, and ICAM-I) increased significantly and those of anti-inflammatory (IL-10) decreased. I/R insult increased the brain volume and aggravated cerebral infarct formation. Histopathological examination of the rat brain revealed vascular congestion, cerebral edema, leukocyte infiltration, and brain tissue necrosis. Interestingly, seven days pretreatment with MeCO (200 and 400 mg/kg) alleviated all the I/R-induced perturbances (neurobehavioral, and motor functions, biochemical, morphological and histopathological) compared with the I/R control. CONCLUSIONS: The MeCO exhibit potent cerebroprotective activity through its potent antioxidant and anti-inflammatory mechanisms, and hence may be useful in the management of ischemic stroke and associated complications.

Ameliorative potential of Colebrookea oppositifolia methanolic root extract against experimental models of epilepsy: Possible role of GABA mediated mechanism.

BACKGROUND: Colebrookea oppositifolia Smith is one of the commonly used plants to treat epilepsy by various folk medicine communities like nomadic Gujjars, Tharu and Bhoxa in sub-Himalayan regions of India. PURPOSE: The present study was undertaken to evaluate the anticonvulsant activity of roots of Colebrookea oppositifolia using various experimental models of epilepsy in mice. METHODS: Petroleum ether extract of roots of C. Oppositifolia (PeCO), methanolic eCO (MeCO) and aqueous eCO (AeCO) was initially evaluated in six-hertz-seizure test in mice, the effective extract was further evaluated against maximal electroshock (MES) and pentylenetetrazole (PTZ) models in mice. In addition, the potent extract was evaluated against the PTZ model by co-administering with flumazenil (FMZ), and also evaluated for its effect on brain GABA levels in brain and NMDA-induced lethality in mice. Furthermore, the possible locomotor deficit-inducing property of the extract was evaluated by actophotometer test in mice. RESULTS: In six-hertz-seizure test the MeCO (25, 50, 100 and 200mg/kg) and AeCO (50, 100, 200, 400 and 800mg/kg) showed significant protection compared to control group, and MeCO was more potent than AeCO. Based on these outcomes, only MeCO was evaluated in MES and PTZ models. Notably, the MeCO (25, 50, 100 and 200mg/kg) has offered significant and dose- dependent protection against MES and PTZ-induced seizures in mice. Alongside, the MeCO (100 and 200mg/kg) showed a significant increase in GABA levels in the brain compared to control. In line with these findings, the anti-PTZ effect of MeCO (100mg/kg, p.o.) was blocked when co-administered with flumazenil (3mg/kg, i.p.),and in NMDA-induced mortality test, the MeCO has shown only 50% protection at 200mg/kg dose, thus confirmed the significant role of GABA pathway. Interestingly, the MeCO did not cause significant change in locomotor activity compared to before treatment. CONCLUSION: These findings suggest that MeCO possess significant anticonvulsant activity and the outcomes further confirmed the involvement of GABAergic mechanisms behind the anticonvulsant activity of MeCO.

Achyranthes aspera Attenuates epilepsy in experimental animals: possible involvement of GABAergic mechanism.

The present study was aimed to examine the possible anticonvulsant property of aerial parts of Achyranthes aspera using various experimental models of epilepsy in mice. Petroleum ether extract of aerial parts of A. aspera (PeAA), methanolic eAA (MeAA) and aqueous eAA (AeAA) was initially evaluated against six-hertz seizure model in mice, based on the outcomes the effective extract was further evaluated against maximal electroshock (MES) and pentylenetetrazole (PTZ) models in mice. In addition, the potent extract was evaluated against the PTZ model by co-administering with flumazenil (FMZ), and also evaluated for its effect on GABA levels in brain and NMDA-induced lethality in mice. Furthermore, the probable locomotor deficit-inducing property of the extract was evaluated by actophotometer test in mice. In results, only MeAA showed protection against six-hertz-induced seizures in mice, based on these outcomes only MeAA was evaluated in MES and PTZ models. Notably, the MeAA (200, 400 and 800 mg/kg) has offered mild and dose dependent protection against MES and PTZ-induced seizures in mice. Alongside, the MeAA (400 mg/kg) showed a significant increase in GABA levels in the brain compared to control, and in line with these findings the anti-PTZ effect of MeAA (400 mg/kg, p.o.) was blocked when co-administered with flumazenil (5 mg/kg, i.p.). However, the MeAA has not shown significant protection against NMDA-induced mortality and also did not cause significant change in locomotor activity compared to before treatment. These findings suggest that MeAA possess mild anticonvulsant activity and the outcomes further confirmed the involvement of GABAergic mechanism behind the anticonvulsant activity of MeAA.

Evaluation of anti-epileptic activity of leaf extracts of Punica granatum on experimental models of epilepsy in mice.

OBJECTIVES: This study was aimed to examine the anti-epileptic activity of leaf extracts of Punica granatum in experimental models of epilepsy in Swiss albino mice. MATERIALS AND METHODS: Petroleum ether leaf extract of P. granatum (PLPG), methanolic LPG (MLPG), and aqueous LPG (ALPG) extracts of P. granatum leaves was initially evaluated against 6-Hz-induced seizure model; the potent extract was further evaluated against maximal electroshock (MES) and pentylenetetrazole (PTZ)-induced convulsions. Further, the potent extract was evaluated for its influence on Gamma amino butyric acid (GABA) levels in brain, to explore the possible mechanism of action. In addition, the potent extract was subjected to actophotometer test to assess its possible locomotor activity deficit inducing action. RESULTS: In 6-Hz seizure test, the MLPG has alleviated 6-Hz-induced seizures significantly and dose dependently at doses 50, 100, 200, and 400 mg/kg. In contrast, PLPG and ALPG did not show any protection, only high dose of ALPG (400 and 800 mg/kg, p.o.) showed very slight inhibition. Based on these observations, only MLPG was tested in MES and PTZ models. Interestingly, the MLPG (50, 100, 200 and 400 mg/kg) has offered significant and dose-dependent protection against MES (P < 0.01) and PTZ-induced (P < 0.01) seizures in mice. Further, MLPG showed a significant increase in brain GABA levels (P < 0.01) compared to control and showed insignificant change in locomotor activity in all tested doses (100, 200 and 400 mg/kg). Interestingly, higher dose of MLPG (400 mg/kg, p.o.) and Diazepam (5 mg/mg, p.o.) have completely abolished the convulsions in all the anticonvulsant tests. CONCLUSION: These findings suggest that MLPG possesses significant anticonvulsant property, and one of the possible mechanisms behind the anticonvulsant activity of MLPG may be through enhanced GABA levels in the brain.

Methanolic leaf extract of Gymnema sylvestre augments glucose uptake and ameliorates insulin resistance by upregulating glucose transporter-4, peroxisome proliferator-activated receptor-gamma, adiponectin, and leptin levels in vitro.

AIMS: The present study was undertaken to evaluate the effect of methanolic leaf extract of Gymnema sylvestre (MLGS) on glucose transport (GLUT) and insulin resistance in vitro. MATERIALS AND METHODS: Peroxisome proliferator-activated receptor-gamma (PPAR-γ) and GLUT-4 expression were assessed in L6 myotubes for concluding the GLUT activity, and adiponectin and leptin expression was studied in 3T3 L1 murine adipocyte cell line to determine the effect of MLGS (250-750 µg/ml) on insulin resistance. RESULTS: The findings of the experiments have demonstrated a significant and dose-dependent increase in glucose uptake in all the tested concentrations of MLGS, further the glucose uptake activity of MLGS (750 µg/ml) was at par with rosiglitazone (50 µg/ml). Concomitantly, MLGS has shown enhanced GLUT-4 and PPAR-γ gene expressions in L6 myotubes. Furthermore, cycloheximide (CHX) had completely abolished the glucose uptake activity of MLGS when co-incubated, which further confirmed that glucose uptake activity of MLGS was linked to enhanced expression of GLUT-4 and PPAR-γ. In addition, in another experimental set, MLGS showed enhanced expression of adiponectin and leptin, thus confirms the ameliorative effect of MLGS on insulin resistance. CONCLUSION: These findings suggest that MLGS has an enhanced glucose uptake activity in L6 myotubes, and ameliorate the insulin resistance in 3T3 L1 murine adipocyte cell line in vitro.

A novel 11ß-hydroxysteroid dehydrogenase type1 inhibitor CNX-010-49 improves hyperglycemia, lipid profile and reduces body weight in diet induced obese C57B6/J mice with a potential to provide cardio protective benefits.

BACKGROUND: 11ß-hydroxysteroid dehydrogenase type1 (11ß-HSD1) converts inactive glucocorticoids to active glucocorticoids which, in excess, leads to development of the various risk factors of the metabolic syndrome. Recent studies clearly suggest that both increased expression and activity of 11ß-HSD1 in metabolically active tissues such as liver, muscle and adipose are implicated in tissue specific dysregulation which collectively contribute to the whole body pathology seen in metabolic syndrome. In the present study we have evaluated CNX-010-49, a highly potent, selective and 'pan tissue' acting 11ß-HSD1 inhibitor, for its potential to modulate multiple risk factors of the metabolic syndrome. METHODS: Male C57B6/J mice on high fat diet (DIO mice) were orally dosed with CNX-010-49 (30 mg/kg twice daily; n = 8) or vehicle for 10 weeks. Fasting glucose, triglycerides, glycerol, free fatty acids, body weight and feed intake were measured at selected time points. At the end of the treatment an OGTT and subsequently organ histology was performed. In vitro, CNX-010-49 was evaluated in 3T3-L1 preadipocytes to assess impact on adipocytes differentiation, hypertrophy and lipolysis whereas in fully differentiated C2C12 cells and in primary mouse hepatocytes to assess the impact on glucose metabolism and hepatic glucose output respectively. RESULTS: CNX-010-49 a highly potent and selective pan tissue acting 11ß-HSD1 inhibitor (EC50 = 6 nM) significantly inhibits glucocorticoids and isoproterenol mediated lipolysis in mature 3T3-L1 adipocytes, improves muscle glucose oxidation, reduces proteolysis and enhances mitochondrial biogenesis. Also a significant inhibition of gluconeogenesis in primary mouse hepatocytes was observed. The treatment with CNX-010-49 resulted in a significant decrease in fasting glucose, improved insulin sensitivity and glucose tolerance. Treatment also resulted in a significant decrease in serum triglycerides levels and a complete inhibition of body weight gain without affecting feed consumption. A significant reduction in the serum biomarkers like Plasminogen activator inhibitor-1 (PAI-1), interleukin 6 (IL-6) and Fetuin-A with CNX-010-49 treatment was observed indicating a potential to modulate processes implicated in cardiovascular benefits. CONCLUSIONS: These results indicate that inhibition of 11ß-HSD1 with CNX-010-49 can give a potential benefit in the management of metabolic dysregulations that are seen in type 2 diabetes.

CNX-013-B2, a unique pan tissue acting rexinoid, modulates several nuclear receptors and controls multiple risk factors of the metabolic syndrome without risk of hypertriglyceridemia, hepatomegaly and body weight gain in animal models.

BACKGROUND: In addition to their role in growth, cellular differentiation and homeostasis Retinoid X Receptors (RXR) regulate multiple physiological and metabolic pathways in various organs that have beneficial glucose and lipid (cholesterol) lowering, insulin sensitizing and anti-obesity effects. Rexinoids, compounds that specifically binds and activate RXR, are therefore considered as potential therapeutics for treating metabolic syndrome. Apparently many of the rexinoids developed in the past increased triglycerides, caused hepatomegaly and also suppressed the thyroid hormone axis. The aim of this study is to evaluate CNX-013-B2, a potent and highly selective rexinoid, for its potential to treat multiple risk factors of the metabolic syndrome. METHODS: CNX-013-B2 was selected in a screening system designed to identify compounds that selectively activated only a chosen sub-set of heterodimer partners of RXR of importance to treat insulin resistance. Male C57BL/6j mice (n = 10) on high fat diet (HFD) and 16 week old ob/ob mice (n = 8) were treated orally with CNX-013-B2 (10 mg/kg twice daily) or vehicle for 10 weeks and 4 weeks respectively. Measurement of plasma glucose, triglyceride, cholesterol including LDL-C, glycerol, free fatty acids, feed intake, body weight, oral glucose tolerance and non-shivering thermogenesis were performed at selected time points. After study termination such measurements as organ weight, triglyceride content, mRNA levels, protein phosphorylation along with histological analysis were performed. RESULTS: CNX-013-B2 selectively activates PPARs- α, ß/δ and γ and modulates activity of LXR, THR and FXR. In ob/ob mice a significant reduction of 25% in fed glucose (p < 0.001 ), a 14% (p < 0.05) reduction in serum total cholesterol and 18% decrease (p < 0.01) in LDL-C and in DIO mice a reduction of 12% (p < 0.01 ) in fasting glucose, 20% in fed triglyceride (p < 0.01) and total cholesterol (p < 0.001) levels, coupled with enhanced insulin sensitivity, cold induced thermogenesis and 7% reduction in body weight were observed. CONCLUSION: CNX-013-B2 is an orally bio available selective rexinoid that can be used as a novel therapeutic agent for management of multiple risk factors of the metabolic syndrome without the risk of side effects reported to be associated with rexinoids.

CNX-011-67, a novel GPR40 agonist, enhances glucose responsiveness, insulin secretion and islet insulin content in n-STZ rats and in islets from type 2 diabetic patients.

BACKGROUND: GPR40 is a G-protein coupled receptor regulating free fatty acid induced and also glucose induced insulin secretion. We generated neonatally-streptozotocin-treated female rats (n-STZ) and treated them with CNX-011-67, a GPR40 agonist to examine the role of GPR40 in modulation of glucose metabolism, insulin secretion and content. METHODS: Female n-STZ animals were orally administered with CNX-011-67 (15 mg/kg body weight, twice daily) or with vehicle for 8 weeks (n = 8 per group). Glucose tolerance in treated animals and insulin secretion, islet insulin content and gene expression in isolated islets were determined. Islets from type 2 diabetic mellitus (T2DM) patients were treated with different concentrations of glucose in presence or absence of CNX-011-67 and insulin secretion was measured. RESULTS: Treatment of n-STZ rats with GPR40 agonist CNX-011-67 enhanced insulin secretion in response to oral glucose load on day 0 and this response persisted during the treatment period. The treatment also produced a 'memory effect' during which insulin secretion in response to oral glucose load remained enhanced, for a week, even in absence of the agonist. Activation of GPR40 enhanced responsiveness of islets to glucose and increased glucose induced insulin secretion and islet insulin content. An increase in islet mRNA expression of GCK, PDX1, insulin and PC was also observed. Acute treatment of islets from n-STZ rats with GPR40 agonist enhanced cellular ATP content. Activation of GPR40 enhanced mitochondrial calcium level in NIT-1 insulinoma cells. CNX-011-67 increased insulin secretion in islets from T2DM patients which were non-responsive to increased glucose concentration CONCLUSIONS: Our data provide evidence that activation of GPR40 with CNX-011-67 stimulates glucose metabolism, enhances glucose responsiveness, increases insulin secretion and content and that pharmacological activation of GPR40 will prove beneficial for treatment of T2DM.

CNX-012-570, a direct AMPK activator provides strong glycemic and lipid control along with significant reduction in body weight; studies from both diet-induced obese mice and db/db mice models.

OBJECTIVES: AMP activated protein kinase (AMPK) regulates the coordination of anabolic and catabolic processes and is an attractive therapeutic target for T2DM, obesity and metabolic syndrome. We report the anti-hyperglycemic and anti-hyperlipidemic effects of CNX-012-570 is an orally bioavailable small molecule (molecular weight of 530 Daltons) that directly activates AMPK in DIO and db/db animal models of diabetes. METHODS: Activity and efficacy of the compound was tested in cell based as well as cell free systems in vitro. Male C57BL/6 mice fed with high fat diet (HFD) were assigned to either vehicle or CNX-012-570 (3 mg/kg, orally once a day) for 8 weeks (n = 8). Genetically diabetic db/db mice on chow diet were dosed with vehicle control or CNX-012-570 (2.5 mg/kg, orally once a day) for 6 weeks (n = 8). RESULTS: CNX-012-570 is a highly potent and orally bioavailable compound activating AMPK in both cell and cell free systems. It inhibits lipolysis (33%) and gluconeogenesis (28%) in 3T3L1 cells and rat primary hepatocytes respectively. The efficacy of the molecule was translated to both DIO and db/db animal models of diabetes. CNX-012-570 has reduced fasting blood glucose levels by 14%, body weight by 24% and fasting serum triglycerides (TG) by 24%. CNX-012-570 showed a 22% reduction in fed serum cholesterol levels and 19% increase in HDL levels.In db/db mice model, CNX-012-570 has shown 18% decrease in fed glucose and 32% decrease in fasting glucose with a 2.57% reduction in absolute HbA1c. Decrease in serum insulin and glucose AUC indicates the increased insulin sensitivity. Body weight was reduced by 13% with increased browning of adipose tissue and decreased inguinal and mesenteric fat mass. There was significant reduction in liver TG and liver total cholesterol. CONCLUSIONS: CNX-012-570 has the potential to control hyperglycemia and hyperlipidemia. It also reduces body weight gain with an additional benefit of minimizing cardiovascular risks in diabetics.

Methanolic extract of Momordica cymbalaria enhances glucose uptake in L6 myotubes in vitro by up-regulating PPAR-γ and GLUT-4.

The present study was undertaken to evaluate the influence of the methanolic fruit extract of Momordica cymbalaria (MFMC) on PPARγ (Peroxisome Proliferator Activated Receptor gamma) and GLUT-4 (Glucose transporter-4) with respect to glucose transport. Various concentrations of MFMC ranging from 62.5 to 500 µg·mL(-1) were evaluated for glucose uptake activity in vitro using L6 myotubes, rosiglitazone was used as a reference standard. The MFMC showed significant and dose-dependent increase in glucose uptake at the tested concentrations, further, the glucose uptake activity of MFMC (500 µg·mL(-1)) was comparable with rosigilitazone. Furthermore, MFMC has shown up-regulation of GLUT-4 and PPARγ gene expressions in L6 myotubes. In addition, the MFMC when incubated along with cycloheximide (CHX), which is a protein synthesis inhibitor, has shown complete blockade of glucose uptake. This indicates that new protein synthesis is required for increased GLUT-4 translocation. In conclusion, these findings suggest that MFMC is enhancing the glucose uptake significantly and dose dependently through the enhanced expression of PPARγ and GLUT-4 in vitro.

Treatment with CNX-011-67, a novel GPR40 agonist, delays onset and progression of diabetes and improves beta cell preservation and function in male ZDF rats.

BACKGROUND: The role of G protein-coupled receptor (GPR40), which is highly expressed in pancreatic beta cells, has been studied extensively in the amelioration of beta cell dysfunction in T2D using rat and mouse islets, beta cell lines and in animal models of diabetes. But its potential as a therapeutic target has not been fully explored. This aim of the study is to evaluate the therapeutic potential of CNX-011-67, a highly selective, potent and orally bioavailable GPR40 agonist, in controlling diabetes and other metabolic parameters. METHODS: Seven week old male ZDF rats were treated with either vehicle or CNX-011-67, 5 mg/kg twice daily, for seven weeks. The animals were subjected to oral glucose tolerance and insulin tolerance tests. Plasma glucose, insulin, triglyceride, HbA1c, fructosamine and free fatty acids were measured at selected time points. Pancreas from control and treated animals were subjected to insulin and pancreatic and duodenal homeobox 1 (PDX1) immunohistochemistry and were also evaluated by electron microscopy. Also the potential impact of CNX-011-67 on islet insulin secretion, content, ATP levels and markers of both glucose oxidation, beta cell health in rat islets under chronic glucolipotoxic conditions was evaluated. RESULTS: Treatment of male ZDF rats with CNX-011-67 for 7 weeks significantly enhanced insulin secretion in response to oral glucose load, delayed the onset of fasting hyperglycemia by 3 weeks, reduced nonfasting glucose excursions, fasting free fatty acids and triglyceride levels. A significant increase in PDX1 expression and insulin content and reduction in plasma fructosamine, HOMA-IR, and beta cell apoptosis were observed. CNX-011-67 improves glucose mediated insulin secretion, insulin gene transcription and islet insulin content in cultured rat islets under chronic glucolipotoxic condition. Also enhanced glucose oxidation in the form of increased islet ATP content and overall improvement in beta cell health in the form of reduced expression of stress markers (TXNIP and CHOP mRNA) were observed. CONCLUSIONS: These findings, suggest that long-term oral therapy with CNX-011-67 could be of clinical value to provide good glycemic control and improve islet beta cell function.

Curcumin, an active component of turmeric in the prevention and treatment of ulcerative colitis: preclinical and clinical observations.

Inflammatory bowel disease (IBD) comprising of ulcerative colitis (UC) and Crohn's disease (CD) is a major ailment affecting the small and large bowel. In clinics, IBD is treated using 5-amninosalicylates, antibiotics, the steroids and immunomodulators. Unfortunately, the long term usages of these agents are associated with undue side effects and compromise the therapeutic advantage. Accordingly, there is a need for novel agents that are effective, acceptable and non toxic to humans. Preclinical studies in experimental animals have shown that curcumin, an active principle of the Indian spice turmeric (Curcuma longa Linn) is effective in preventing or ameliorating UC and inflammation. Over the last few decades there has been increasing interest in the possible role of curcumin in IBD and several studies with various experimental models of IBD have shown it to be effective in mediating the inhibitory effects by scavenging free radicals, increasing antioxidants, influencing multiple signaling pathways, especially the kinases (MAPK, ERK), inhibiting myeloperoxidase, COX-1, COX-2, LOX, TNF-α, IFN-γ, iNOS; inhibiting the transcription factor NF-κB. Clinical studies have also shown that co-administration of curcumin with conventional drugs was effective, to be well-tolerated and treated as a safe medication for maintaining remission, to prevent relapse and improve clinical activity index. Large randomized controlled clinical investigations are required to fully understand the potential of oral curcumin for treating IBD.