The Effect of a 2-Week Red Ginseng Supplementation on Food Efficiency and Energy Metabolism in Mice.

Red ginseng (RG) ingestion reportedly affects body weight, food intake, and fat accumulation reduction. It also induces changes in energy metabolism regulation and glycemic control. Previously, 2-week RG ingestion with endurance training was found to enhance fat oxidation during exercise. However, such effects on energy metabolism and the expression of mRNAs related to energy substrate utilization in resting mice (untrained mice) are still unclear. Here, we determined the effect of RG on energy metabolism and substrate utilization in untrained male mice. Twenty-four mice were separated into an RG group that received a daily dosage of 1 g/kg RG for 2 weeks, and a control (CON). Energy expenditure, blood and tissue glycogen levels, and expression of mRNAs related to energy substrate utilization in muscles were measured before and 2 weeks after treatment. Total food intake was significantly lower in the RG than in the CON group (p < 0.05), but final body weights did not differ. Carbohydrate and fat oxidation over 24 h did not change in either group. There were no significant differences in gastrocnemius GLUT4, MCT1, MCT4, FAT/CD36, and CPT1b mRNA levels between groups. Thus, the effects of RG ingested during rest differ from the effects of RG ingestion in combination with endurance exercise; administering RG to untrained mice for 2 weeks did not change body weight and energy metabolism. Therefore, future studies should consider examining the RG ingestion period and dosage for body weight control and improving energy metabolism.

Hypoglycemic activity of CPU2206: A novel peptide from sika (Cervus nippon Temminck) antler.

Previous work had extracted and purified an antidiabetic peptide named CPU2206 with 7,127.6 Da. In this work, the toxicity of CPU2206 was first evaluated by daily administration to ICR mice, and after 28 days of administration, the body weight and lipid metabolism of the mice did not change significantly, which proved its safety and reliability. Second, further studies have focused on its hypoglycemic effects by daily intraperitoneal injection to alloxan-induced diabetic mice and KK-Ay mice, showing that CPU2206 effectively decreased the blood glucose and corresponding indicators of diabetic mice. Daily administration of CPU2206 nearly normalized the lipid metabolic parameters in diabetic mice. Histological examination also validated that CPU2206 ameliorated the pancreas injuries induced by alloxan or alleviated islet hypertrophy caused by insulin resistance in KK-Ay mice. To sum up, a totally new bioactive peptide CPU2206 obtained from sika antler showed significantly antidiabetic as well as lipid-lowering effects in diabetic mice. PRACTICAL APPLICATIONS: Antler has been used as a traditional Chinese medicine to invigorate primordial energy, enrich the blood, strengthen bones, and improve both male and female sexual functions for thousands of years. Traditionally, velvet antler can be grinded directly and taken orally, or used in porridge, wine and meat stew. Our experiment enriches the research on the function of edible antlers, provides the basis for developing it into functional health food, and on the other hand, provides an idea for finding new antidiabetic drugs.

Dietary Supplementation with Trihexanoin Enhances Intestinal Function of Weaned Piglets.

Trihexanoin is a short-chain triglyceride (SCT). Many studies have reported that SCTs play important roles in the maintenance of intestinal epithelial structure and function. The present work was to investigate the effects of trihexanoin on growth performance, carbohydrate and fat metabolism, as well as intestinal morphology and function in weaned piglets. Twenty weaned piglets (21 ± 2 d) were randomly allocated to one of two treatment groups: The control group (basal diet supplemented with 0.5% soya oil); the TH group (basal diet supplemented with 0.5% trihexanoin). Dietary trihexanoin supplementation significantly reduced diarrhea rate; increased the concentrations of LDL, HDL and total protein in plasma; decreased cholesterol concentrations and glutamyl transpeptidase activity in plasma; improved intestinal morphologic structure; altered the mRNA levels and abundances of proteins related to glycogen and fat metabolism, mucosal barrier function, antioxidant capacity and water transport capacity; and altered the community of intestinal microflora. These results indicate that dietary trihexanoin supplementation could reduce diarrhea, regulate carbohydrate and fat metabolism, exert beneficial effects on the intestinal mucosal barrier, protect the intestinal mucosa from injuries, improve intestinal transport and absorption, and enhance antioxidant capacity. In conclusion, dietary supplementation with 0.5% trihexanoin improves the intestinal function and health of weaned piglets.

Germinated Pigmented Rice (Oryza Sativa L. cv. Superhongmi) Improves Glucose and Bone Metabolisms in Ovariectomized Rats.

The effect of germinated Superhongmi, a reddish brown pigmented rice cultivar, on the glucose profile and bone turnover in the postmenopausal-like model of ovariectomized rats was determined. The ovariectomized Sprague-Dawley rats were randomly divided into three dietary groups (n = 10): normal control diet (NC) and normal diet supplemented with non-germinated Superhongmi (SH) or germinated Superhongmi (GSH) rice powder. After eight weeks, the SH and GSH groups showed significantly lower body weight, glucose and insulin concentrations, levels of bone resorption markers and higher glycogen and 17-ß-estradiol contents than the NC group. The glucose metabolism improved through modulation of adipokine production and glucose-regulating enzyme activities. The GSH rats exhibited a greater hypoglycemic effect and lower bone resorption than SH rats. These results demonstrate that germinated Superhongmi rice may potentially be useful in the prevention and management of postmenopausal hyperglycemia and bone turnover imbalance.

Effects of Resveratrol Supplementation and Exercise Training on Exercise Performance in Middle-Aged Mice.

Resveratrol (RES) has antioxidative, anti-inflammatory, anticancer, antidiabetic, antiasthmatic, antalgic, and anti-fatigue activities. Exercise training (ET) improves frailty resulting from aging. This study evaluated the effects of a combination of RES supplementation and ET on the exercise performance of aged mice. C57BL/6J mice (16 months old) were randomly divided into four groups: an older control group (OC group), supplementation with RES group (RES group), ET group (ET group), and a combination of ET and RES supplementation group (ET+RES group). Other 10-week-old mice were used as a young control group (Y-Ctrl group). In this study, exercise performance was evaluated using forelimb grip strength and exhaustive swimming time, as well as levels of plasma lactate, ammonia, glucose, and creatine kinase after an acute swimming exercise. Our results showed that the forelimb grip strength of mice in the ET+RES group was significantly higher than those in the OC, RES, and ET groups (by 1.3-, 1.2-, and 1.1-fold, respectively, p < 0.05), and exhibited no difference with the Y-Ctrl group. The endurance swimming test showed that swimming times of the ET and ET+RES groups were significantly longer than those of the OC and RES groups. Moreover, plasma lactate and ammonia levels of the ET + RES group after acute swimming exercise were significantly lower compared to the OC group (p < 0.05). Thus, it was suggested that by combining RES supplementation with ET for 4 weeks, the muscle strength and endurance performance of aged mice were significantly improved compared to the single intervention with either RES or ET alone. This combination might help shorten the extent of deterioration accompanying the aging process.

Padina arborescens Ameliorates Hyperglycemia and Dyslipidemia in C57BL/KsJ-db/db Mice, a Model of Type 2 Diabetes Mellitus.

Recently, there has been a growing interest in alternative therapies and in the therapeutic use of natural products for the treatment of diabetes. Therefore, in this study, we investigated the hypoglycemic and hypolipidemic effects of brown algae, Padina arborescens, in an animal model of type 2 diabetes. For 6 weeks, male C57BL/KsJ-db/db mice were administrated either control diet with no treatment or were treated with rosiglitazone (RG; 0.005%, w/w) or P. arborescens extract (PAE; 0.5%, w/w). At the end of the experimental period, the blood glucose levels, glycosylated hemoglobin levels, and plasma insulin levels were significantly lower in the RG and PAE groups compared with the control group. In addition, glucose tolerance was significantly improved in the RG and PAE groups. The homeostatic index of insulin resistance was lower in the RG and PAE groups than the diabetic control group. Also, the total cholesterol, LDL-cholesterol, triglyceride, and free fatty acid levels were lower in the PAE group than in the control group, whereas the HDL-C level was higher in the PAE group. Supplementation with PAE significantly lowered hepatic glucose-6-phosphatase and phosphoenolpyruvate carboxykinase activities, and increased glucokinase activity in the liver. Consequently, these results suggest that PAE may be beneficial in improving insulin resistance, hyperglycemia, and dyslipidemia in type 2 diabetics.

Effect of tangeretin, a polymethoxylated flavone on glucose metabolism in streptozotocin-induced diabetic rats.

The present study was designed to evaluate the antihyperglycemic potential of tangeretin on the activities of key enzymes of carbohydrate and glycogen metabolism in control and streptozotocin induced diabetic rats. The daily oral administration of tangeretin (100mg/kg body weight) to diabetic rats for 30 days resulted in a significant reduction in the levels of plasma glucose, glycosylated hemoglobin (HbA1c) and increase in the levels of insulin and hemoglobin. The altered activities of the key enzymes of carbohydrate metabolism such as hexokinase, pyruvate kinase, lactate dehydrogenase, glucose-6-phosphatase, fructose-1,6-bisphosphatase, glucose-6-phosphate dehydrogenase, glycogen synthase and glycogen phosphorylase in liver of diabetic rats were significantly reverted to near normal levels by the administration of tangeretin. Further, tangeretin administration to diabetic rats improved hepatic glycogen content suggesting the antihyperglycemic potential of tangeretin in diabetic rats. The effect produced by tangeretin on various parameters was comparable to that of glibenclamide - a standard oral hypoglycemic drug. Thus, these results show that tangeretin modulates the activities of hepatic enzymes via enhanced secretion of insulin and decreases the blood glucose in streptozotocin induced diabetic rats by its antioxidant potential.

Evaluation of anti-fatigue activity of total saponins of Radix notoginseng.

BACKGROUND & OBJECTIVES: Several biological activities of total saponins of Radix notoginseng (TSRN), a traditional Chinese medicine, have been reported. The present study was carried out to investigate anti-fatigue activity of TSRN in male Kunming mice. METHODS: Mice were divided into four groups. The first group designated as control group was administered with distilled water by gavage every day. The second, third and fourth groups designated as TSRN treatment groups were administered with TSRN of 20, 40 and 80 mg/kg body weight/day, respectively. The treatment continued for 28 days. Exhaustive swimming time, blood lactate and tissue glycogen contents of mice after swimming were determined. RESULTS: TSRN extended exhaustive swimming time of mice, effectively delayed the increase of lactate in the blood, as well as increased the tissue glycogen contents. INTERPRETATION & CONCLUSIONS: TSRN showed promising anti-fatigue activity in animal model. However, further study is needed to elucidate the mechanism of the effect of TSRN on fatigue.

The hypoglycemic effects of American red ginseng (Panax quinquefolius L.) on a diabetic mouse model.

UNLABELLED: American ginseng (Panax quinquefolius L.) root health benefits include treatment of type 2 diabetes and this study evaluated the hypoglycemic effects of American red ginseng (ARG). ARG roots have increased bioactive phenolic contents, such as cinnamic acid and ferulic acid during the steaming process. The antihyperglycemic effects of methanol fraction extract of ARG, ferulic acid, and cinnamic acid were examined using a type 2 diabetic mouse model. The ARG treated group presented relatively lower blood glucose levels than the control group (P < 0.05). In addition, the glycogen and high density lipoprotein (HDL) contents were significantly increased while levels of plasma cholesterol and low density lipoprotein (LDL) concentration were significantly decreased in the ARG treated group. The groups treated with ferulic and cinnamic acids showed similar effects as those found in the ARG treated group. Thus, it is suggested that ARG roots, ferulic acid, and cinnamic acid have hypoglycemic effects in an animal model. PRACTICAL APPLICATION: This study was conducted to elucidate the hypoglycemic effects of American red ginseng (ARG) using a type 2 diabetic mouse model. ARG showed an enhanced antioxidant capacity and higher antihyperglycemia effect. The glycogen and high density lipoprotein (HDL) contents were significantly increased while levels of plasma cholesterol and low density lipoprotein (LDL) concentration were significantly decreased in the ARG treated group. It is suggested that ARG has a potential to be used for human diabetic treatment.

Antihyperglycemic and antioxidative effects of Hydroxyethyl Methylcellulose (HEMC) and Hydroxypropyl Methylcellulose (HPMC) in mice fed with a high fat diet.

The effect of dietary feeding of hydroxyethyl methylcellulose (HEMC) and hydroxypropyl methylcellulose (HPMC) on the glucose metabolism and antioxidative status in mice under high fat diet conditions was investigated. The mice were randomly divided and given experimental diets for six weeks: normal control (NC group), high fat (HF group), and high fat supplemented with either HEMC (HF+HEMC group) or HPMC (HF+HPMC group). At the end of the experimental period, the HF group exhibited markedly higher blood glucose and insulin levels as well as a higher erythrocyte lipid peroxidation rate relative to the control group. However, diet supplementation of HEMC and HPMC was found to counteract the high fat-induced hyperglycemia and oxidative stress via regulation of antioxidant and hepatic glucose-regulating enzyme activities. These findings illustrate that HEMC and HPMC were similarly effective in improving the glucose metabolism and antioxidant defense system in high fat-fed mice and they may be beneficial as functional biomaterials in the development of therapeutic agents against high fat dietinduced hyperglycemia and oxidative stress.

Effects of a Chinese traditional formula Kai Xin San (KXS) on chronic fatigue syndrome mice induced by forced wheel running.

ETHNOPHARMACOLOGICAL RELEVANCE: In traditional medicine, Kai Xin San (KXS), composed of ginseng (Panax ginseng), hoelen (Wolfiporia cocos), polygala (Polygala tenuifolia) and Acorus gramineus, is famous for the treatment of emotion-thought disease, such as settling fright, quieting the spirit and nourishing the heart. AIM OF THE STUDY: The present study investigated the effect of KXS on chronic fatigue syndrome (CFS) mice induced by forced wheel running. MATERIALS AND METHODS: Seventy two healthy adult male Kunming mice were randomly divided into six groups: home cage control group, CFS group, CFS group with Modafinil treatment at 13 mg/kg/d doge, KXS treatment at 175 mg/kg/d, 350 mg/kg/d and 700 mg/kg/d doge. CFS mice were induced by forced wheel running with higher speed for 4 weeks and then taken an exhausted exercise. The biochemical parameters including serum lactate dehydrogenase (LDH), serum urea nitrogen (SUN), serum testosterone (T), liver glycogen (LG), muscle glycogen (MG) and muscle lactic acid (MLA) were determined by using commercially available kits. The splenocytes proliferation from mice was examined by MTT method. The levels of interleukin-2 (IL-2) and interleukin-4 (IL-4) secreted by splenocytes were determined by ELISA. RESULTS: CFS mice with KXS administration exhibited less electric shock time when compared with CFS group without drug treatment. The effect of KXS has after demonstrated reduction in SUN, LDH and MLA levels and an increase in T, LG and MG levels. CFS mice with KXS could improve the proliferation of splenocytes compared with CFS group without drug treatment. The cultured splenocytes from CFS mice without KXS supplementation produced more interleukin-2 (IL-2) but less interleukin-4 (IL-4) when compared with home cage control mice. The cultured splenocytes of CFS mice with KXS supplementation produced more interleukin-2 (IL-2) but less interleukin-4 (IL-4) when compared with CFS group without drug treatment. CONCLUSIONS: The results of this preliminary study provide evidence that KXS could ameliorate CFS by affecting the physiological markers for fatigue. This study also supported the use of KXS against CFS by improving the proliferation of splenocytes from CFS mice and modulating the disturbance of cytokines induced by CFS.

Metabolic effects of dietary sugar beet pulp or wheat bran in growing female pigs.

An experiment was conducted to determine the effects of feeding a moderate level of 2 different fiber sources on energy metabolites; mitochondrial biogenesis in the intestine, liver, and muscle; and the expression of some genes that regulate energy metabolism in intestine, liver, muscle, and adipose tissue. Female pigs (n = 36; BW = 15.0 ± 0.7 kg) were fed diets containing no added fiber, 12.5% sugar beet pulp (SBP), or 12.5% wheat bran (WB) for 24 d. Blood samples were collected on d 7 and 24 for cholesterol, glucose, NEFA, and triglyceride analyses. At completion of the experiment, ileum, colon, subcutaneous adipose, and LM samples were obtained from a subset (n = 6) of pigs fed each diet for analysis of tissue mitochondrial DNA (mtDNA) content and mRNA abundance by quantitative real-time reverse-transcription PCR. Glycogen and triglyceride content of liver and LM were determined, and colon content VFA was also determined. The addition of SBP or WB to the diet had no effect (P > 0.55) on ADG, ADFI, or G:F. Serum NEFA and triglycerides were increased (P < 0.05) in pigs fed SBP compared with pigs fed the control diet or WB on d 7, and NEFA remained increased (P < 0.05) on d 24 in pigs fed SBP. Dietary fiber had no effect (P > 0.24) on glycogen and triglyceride content of liver or LM, but colonic acetate concentrations were increased (P < 0.05) in pigs fed either SBP or WB. Pigs fed WB had an increased (P < 0.05) mtDNA content in ileum tissue and increased (P < 0.05) citrate synthase mRNA in colon tissue. In the liver, feeding either SBP or WB led to a decrease (P < 0.05) in mtDNA content, whereas feeding WB decreased (P < 0.05) mtDNA abundance in the LM, and feeding either SBP or WB decreased (P < 0.05) expression of citrate synthase mRNA. Quantitative reverse-transcription PCR revealed that feeding WB increased (P < 0.05) proliferating cell nuclear antigen mRNA abundance in the ileum and colon. Feeding WB increased (P < 0.05) mRNA abundance of a regulator of mitochondrial biogenesis, PPAR coactivator 1 α, in ileum tissue, and increased (P < 0.05) mRNA abundance of another mediator of mitochondrial biogensis, sirtuin 1, in colon tissue. Colonic mRNA expression of fasting-induced adipose factor was increased (P < 0.05) in pigs fed either SBP or WB, and adipose triglyceride lipase mRNA abundance was increased (P < 0.05) in adipose tissue of pigs fed SBP. These data indicate that increasing dietary fiber can increase the capacity of the intestine for oxidative metabolism and induce a repartitioning of energy metabolites depending on fiber source.

Efficacy and safety of two analogs of L-carnitine on rats made insulin resistant by a high-fructose diet.

AIM: To evaluate the efficacy and safety of 2 analogs of L-carnitine on rats made insulin resistant by a high-fructose diet. METHODS: Using rats made insulin resistant by a high-fructose diet, we investigated the impact of 2 analogs of L-carnitine (25 mg/kg) and L-carnitine (250 mg/kg) on glucose, triglycerides and cholesterol blood levels, and liver glycogen. We also evaluated the safety of both analogs by the assessment of some biochemical and hematological parameters, a histological analysis and a study of embryotoxicity. RESULTS: Both analogs reduced the levels of triglycerides in the liver and plasma, but only analog 2 reduced the cholesterol levels in insulin-resistant rats. No changes were observed in glycogen content. Safety evaluations revealed alterations in blood lymphocytes and embryotoxicity data. CONCLUSION: This study demonstrated that the 2 analogs maintain the pharmacological properties of L-carnitine but have a different efficacy, potency and toxicity.

Pharmacological evaluation of Potentilla alba L. in mice: adaptogenic and central nervous system effects.

CONTEXT: Potentilla alba L. (Rosaceae) rhizomes have anti-inflammatory, antioxidant, and adaptogenic effects and are used for the treatment of diarrhea and intestinal colic. However, the data concerning the adaptogenic and central nervous system activities of P. alba are fragmentary. OBJECTIVES: To determine the effect of oral administration of dried P. alba extract on the swimming endurance, light/dark exploration, and open-field tests for mice. MATERIALS AND METHODS: The mice were orally administered Rhodiola rosea extract (RR group); dry extract of P. alba at doses of 12, 36, or 72 mg/kg (groups: PA12, PA36, and PA72); or distilled water (control group) for 7 consecutive days. RESULTS: The swimming times of the RR, PA36, and PA72 groups were significantly longer than those of the control group. The administration of P. alba significantly increased the light time, latency time, and the number of rearings in a dose-dependent manner. In the open-field test, the P. alba extract at a dose of 12 mg/kg produced a significant increase in the frequency of head dipping and the number of squares crossed and a significant decrease in grooming compared with the control treatment. CONCLUSION: The current findings demonstrate that P. alba extracts significantly increased swimming endurance time and have anxiolytic-like action with a predominant locomotor component.

Combined treatment of tetrahydrocurcumin and chlorogenic acid exerts potential antihyperglycemic effect on streptozotocin-nicotinamide-induced diabetic rats.

We have shown that separate dose of tetrahydrocurcumin (THC) at a dose of 80 mg/kg body weight (b.w.) and chlorogenic acid (CGA) at a dose of 5 mg/kg b.w. exerts antidiabetic potential in streptozotocin (STZ) (45 mg/kg b.w.) nicotinamide induced diabetic rats. In the present study we have attempted to compare the antihyperglycemic activity exerted by the combined treatment of THC/CGA with THC and CGA alone treated diabetic rats. After the experimental period of 45 days we observed that supplementation with combined dose of THC/CGA significantly decreased glycosylated hemoglobin (HbA(1C)) and increased the levels of plasma insulin, C-peptide, hemoglobin and glycogen which were decreased upon STZ treatment and also significantly reversed the altered activities of gluconeogenic enzymes such as glucose-6-phosphatase, fructose-1,6-bisphosphatase, and of glycolytic enzymes such as glucokinase and hexokinase in the tissues of experimental rats as compared to their individual supplementation. Thus our results substantiate that though THC and CGA alone found to exert hypoglycemic activity the maximum hypoglycemic effect was always observed in diabetic rats treated THC/CGA and this summed effect seems to have a promising value for the development of a potent phytomedicine for diabetes.

Antioxidant effect of dietary supplement Withania somnifera L. reduce blood glucose levels in alloxan-induced diabetic rats.

The phenolic compounds and flavonoids were determined from the extracts of Withania somnifera root (WSREt) and leaf (WSLEt). The WSREt has 28.26 mg/g total phenolic compounds and 17.32 mg/g flavonoids, whereas WSLEt has 5.4 mg/g total phenolic compounds and 5.1 mg/g flavonoids. The WSREt, WSLEt and glibenclamide were orally administered daily to diabetic rats for 8 weeks. After the treatment, the levels of urine sugar, blood glucose, liver glycogen, and antioxidants like vitamin C and E in plasma and superoxide dismutase (SOD), catalase (CAT), thiobarbituric acid reactive substances (TBARS), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and reduced glutathione (GSH) in liver, kidney and heart were determined. Diabetic rats showed a significant (p < 0.05) elevation in glucose and TBARS and a significant (p < 0.05) reduction in glycogen, vitamin C and E, SOD, CAT, GPx, GST, and GSH levels when compared to normal control rats. Administration of WSREt, WSLEt and glibenclamide to diabetic rats restored the levels to normal. In the light of aforesaid facts, it is suggested that the presence of phenolic compounds including flavonoids in W. somnifera root and leaf extracts and their antioxidant activity may play a vital role in reduction of blood glucose level in alloxan-induced diabetic rats.

Antidiabetic and antilipidemic effect of eremanthin from Costus speciosus (Koen.)Sm., in STZ-induced diabetic rats.

The increasing prevalence of diabetes mellitus worldwide is an issue of major socio-economic concern. Diabetes mellitus is a complex and a multifarious group of disorders that disturbs the metabolism of carbohydrates, fat and protein. Medicinal plants play an important role in the management of diabetes mellitus especially in developing countries. Costus speciosus is widely used in Indian medicine to treat various diseases. Eremanthin was isolated from C. speciosus. The structure was identified using gas chromatography-mass spectrometry (GC-MS) analysis. Eremanthin was administered to streptozotocin (STZ) (50mg/kg bw) induced diabetic male Wistar rats at different doses (5, 10, 20mg/kg bw) for 60 days. Plasma glucose level was significantly (p<0.05) reduced in a dose dependent manner when compared to the control. In addition, oral administration of eremanthin (20mg/kg bw) significantly decreased glycosylated hemoglobin (HbA(1c)), serum total cholesterol, triglyceride, LDL-cholesterol and at the same time markedly increased plasma insulin, tissue glycogen, HDL-cholesterol and serum protein. Eremanthin also restored the altered plasma enzyme (aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, alkaline phosphatase and acid phosphatase) levels to near normal. Results of this experimental study indicated that eremanthin possessed hypoglycemic and hypolipidemic activities and hence it could be used as a drug for treating diabetes.

Normo-glycemic and hypolipidemic effect of costunolide isolated from Costus speciosus (Koen ex. Retz.)Sm. in streptozotocin-induced diabetic rats.

Diabetes mellitus is the most common and serious metabolic disorder among people all over the world. Many plants have successfully been used to overcome this problem. Costus speciosus is widely used in Indian medicine to treat various diseases including diabetes. Bioassay guided fractionation was followed to isolate costunolide from the hexane extract of C. speciosus root. The structure was elucidated using X-ray crystallography. Costunolide was administered to streptozotocin (STZ) (50 mg/kg bw)-induced diabetic male wistar rats at different doses (5, 10, 20 mg/kg bw) for 30 days to assess its effect on fasting plasma glucose and cholesterol levels. It was found that plasma glucose was significantly (p<0.05) reduced in a dose-dependent manner when compared to the control. In addition, oral administration of costunolide (20 mg/kg bw) significantly decreased glycosylated hemoglobin (HbA(1c)), serum total cholesterol, triglyceride, LDL cholesterol and at the same time markedly increased plasma insulin, tissue glycogen, HDL cholesterol and serum protein. Also costunolide restored the altered plasma enzyme (aspartate aminotransferase, alanine aminotrasferase, lactate dehydrogenase, alkaline phosphatase and acid phosphatase) levels to near normal. Costunolide might have stimulated the beta islets to secrete insulin by inhibiting the expression of nitric oxide synthase. The results of this experimental study indicated that costunolide possessed normo-glycemic and hypolipidemic activity and hence it could be used as a drug for treating diabetes.

Cinnamaldehyde--a potential antidiabetic agent.

Cinnamonum zeylanicum (cinnamon) is widely used in traditional system of medicine to treat diabetes in India. The present study was carried out to isolate and identify the putative antidiabetic compounds based on bioassay-guided fractionation; the compound identified decreased the plasma glucose levels. The active compound was purified by repeat column and structure of cinnamaldehyde was determined on the basis of chemical and physiochemical evidence. The LD(50) value of cinnamaldehyde was determined as 1850+/-37 mg/kg bw. Cinnamaldehyde was administered at different doses (5, 10 and 20 mg/kg bw) for 45 days to streptozotocin (STZ) (60 mg/kg bw)-induced male diabetic wistar rats. It was found that plasma glucose concentration was significantly (p<0.05) decreased in a dose-dependent manner (63.29%) compared to the control. In addition, oral administration of cinnamaldehyde (20 mg/kg bw) significantly decreased glycosylated hemoglobin (HbA(1C)), serum total cholesterol, triglyceride levels and at the same time markedly increased plasma insulin, hepatic glycogen and high-density lipoprotein-cholesterol levels. Also cinnamaldehyde restored the altered plasma enzyme (aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, alkaline phosphatase and acid phosphatase) levels to near normal. Administration of glibenclamide, a reference drug (0.6 mg/kg bw) also produced a significant (p<0.05) reduction in blood glucose concentration in STZ-induced diabetic rats. The results of this experimental study indicate that cinnamaldehyde possesses hypoglycemic and hypolipidemic effects in STZ-induced diabetic rats.

Selenium and glycogen levels in diabetic patients.

Selenium in serum and selenium and glycogen in erythrocytes were determined in diabetic patients divided into noninsulin-dependent (n = 50) and insulin-dependent (n = 31) groups according to the etiopathogenesis of their diabetes. Selenium was determined by the method of atomic absorption spectrometry. Serum level of selenium was statistically significantly different in patients with either noninsulin-dependent (59.23 +/- 12.2 microg/L) or insulin-dependent (58.23 +/- 16.7 microg/L) diabetes mellitus as compared with the control group of 62 subjects (64.2 +/- 11.5 microg/L; p < 0.05). There was no statistically significant difference in the serum levels of selenium between the groups of patients with noninsulin-dependent and insulin-dependent diabetes mellitus. The levels of erythrocyte glycogen were 2.0580 +/- 1.326, 2.0380 +/- 1.735, and 2.0036 +/- 1.3537 microg/g Hb in the control group, noninsulin-dependent group, and insulin-dependent group, respectively, with no statistically significant between-group difference. The decreased levels of selenium in serum and erythrocytes of diabetic patients suggest the possible role of glutathione peroxidase activity.