Serum Glucose Levels In Mice Research Articles

Bioactivity and chemical characterization of gonads of green sea urchin Strongylocentrotus droebachiensis from Barents Sea

The gonads of sea urchins have been consumed by humans since ancient times. However, relatively little information is available on their biological activity. In the present study, we have consecutively extracted gonads of green sea urchins Strongylocentrotus droebachiensis from Barents Sea with chloroform-95% EtOH (4:1, v/v), (fraction ESD1), 95% EtOH (ESD2), and 70% EtOH (ESD3), characterized the fractions by GC-MS and HPLC, and further investigated their bioactivities.The cyclooxygenase-2 was inhibited by 62% with ESD1 and by 39% with ESD2. All the extracts from gonads significantly prevented the decrease in body weight of mice having streptozotocin–nicotinamide-induced (STZ/NA) diabetes. ESD2 significantly reduced serum glucose level in mice after 5 days of administration. The 50% inhibition of dipeptidyl peptidase IV was observed at a dose of 20 µg/ml of ESD2. These results suggest that sea urchin gonads may serve as a functional food for the management of inflammatory diseases and diabetes.

Antihyperglycemic Effect of Various Fractions from Residues of Blumea balsamifera

ObjectiveTo evaluate the antihyperglycemic activities of various fractions from the residues of Blumea balsamifera (BB), and to properly utilize the waste resource. MethodsThe antihyperglycemic activities were evaluated by the suppression on serum glucose level in vivo and α-glucosidase inhibition assay in vitro. The high-, mid-, and low-dose (1, 0.5, and 0.25 g/kg of the herb) fractions were ig given to mice for 8 d. The serum glucose was monitored at 1 and 12 h after feeding. ResultsThe fasting and postprandial serum glucose levels of mice treated with high-dose petroleum ether fraction, ethyl acetate fraction, butyl alcohol fraction, methanol fraction, and water extract from BB were 4.45, 4.39, 4.43, 4.15, 3.74 mmol/L and 6.98, 6.23, 6.45, 6.26, 5.88 mmol/L, respectively, while those in vehicle control group were 5.63 and 7.50 mmol/L. There are four different inhibiting manners by the results of α-glucosidase inhibition assay. ConclusionThe residues of BB have anti-diabetes activities after steam distillation.

The Adenosine Receptor Agonist 5’-<i>N</i>-Ethylcarboxamide-Adenosine Increases Glucose 6-Phosphatase Expression and Gluconeogenesis

Intraperitoneal administration of the non-selective adenosine receptor agonist 5’-N-ethylcarboxamide-adenosine (NECA) (0.1 or 0.3 mg/kg) increased fasting serum glucose levels in mice. To clarify the mechanism responsible for this, the expression of liver glucose 6-phosphatase (G6Pase: a gluconeogenic enzyme) was analyzed, and it was found that G6Pase mRNA was increased by NECA treatment. Administration of 0.3 mg/kg NECA resulted in elevated serum glucose levels at 1 h and were further elevated at 6 h. Administration of 0.1 mg/kg NECA increased serum glucose levels at 1 h and had returned to control levels by 6 h. The increase in fasting serum glucose levels induced by NECA are thought to be caused, in part, by elevated G6Pase expression.

Antihyperglycemic and antinociceptive activities of methanolic extract of Euphorbia thymifolia L. whole plants

To study the antihyperglycemic and antinociceptive activities of methanolic extract of the whole plant of Euphorbia thymifolia L., a plant used in folk medicine of Bangladesh for treatment of diabetes and pain. Antihyperglycemic activity studies were conducted in glucose-loaded mice by oral glucose tolerance tests. Mice were given various doses of the extract, followed by glucose (2 g/kg body weight), 1 h after administration of the extract. Serum glucose levels were measured 2 h after glucose administration. Antinociceptive activity studies were conducted in intraperitoneally acetic acid-injected mice through measurement of reductions in abdominal writhing times caused by acetic acid-induced gastric pain. Following a period of 1 h after oral administration of various doses of the extract, all mice received intraperitoneal injection of 1% acetic acid at a dose of 10 mL/kg body weight. To ensure bioavailability of acetic acid, a period of 5 min was given to each animal following which period the number of writhings was counted for 10 min. The extract caused a significant dose-dependent reduction in serum glucose levels in mice, when administered at doses of 50, 100, 200 and 400 mg/kg body weight as compared to the control animals (P<0.05). The highest reduction of serum glucose (60.5%) was observed at a dose of 400 mg/kg. In comparison, a standard antihyperglycemic drug glibenclamide, when administered at a dose of 10 mg/kg body weight, lowered serum glucose levels by 48.6%. The extract also demonstrated a significant dose-dependent antinociceptive activity compared to control animals (P<0.05). At a dose of 400 mg/kg body weight, the number of abdominal writhings was inhibited by 40.9% as compared to 49.0% inhibition obtained with a standard antinociceptive drug aspirin, administered at a dose of 200 mg/kg body weight. The significant antihyperglycemic and antinociceptive activities demonstrated by the extract validate the use of E. thymifolia in folk medicine of Bangladesh for treatment of diabetes and pain, and merit further scientific studies leading to discovery of efficacious drugs.

Cannabinoids Ameliorate Pain and Reduce Disease Pathology in Cerulein-Induced Acute Pancreatitis

The functional involvement of the endocannabinoid system in modulation of pancreatic inflammation, such as acute pancreatitis, has not been studied to date. Moreover, the therapeutic potential of cannabinoids in pancreatitis has not been addressed. We quantified endocannabinoid levels and expression of cannabinoid receptors 1 and 2 (CB1 and CB2) in pancreas biopsies from patients and mice with acute pancreatitis. Functional studies were performed in mice using pharmacological interventions. Histological examination, serological, and molecular analyses (lipase, myeloperoxidase, cytokines, and chemokines) were performed to assess disease pathology and inflammation. Pain resulting from pancreatitis was studied as abdominal hypersensitivity to punctate von Frey stimuli. Behavioral analyses in the open-field, light-dark, and catalepsy tests were performed to judge cannabinoid-induced central side effects. Patients with acute pancreatitis showed an up-regulation of cannabinoid receptors and elevated levels of endocannabinoids in the pancreas. HU210, a synthetic agonist at CB1 and CB2, abolished abdominal pain associated with pancreatitis and also reduced inflammation and decreased tissue pathology in mice without producing central, adverse effects. Antagonists at CB1- and CB2-receptors were effective in reversing HU210-induced antinociception, whereas a combination of CB1- and CB2-antagonists was required to block the anti-inflammatory effects of HU210 in pancreatitis. In humans, acute pancreatitis is associated with up-regulation of ligands as well as receptors of the endocannabinoid system in the pancreas. Furthermore, our results suggest a therapeutic potential for cannabinoids in abolishing pain associated with acute pancreatitis and in partially reducing inflammation and disease pathology in the absence of adverse side effects.

Rubratoxin B caused hypoglycemia and elevated serum interleukin-6 levels in mice.

In order to find serological marker(s) of rubratoxin B′s toxicity, the effects of rubratoxin B on serum transaminases, glucose, triglyceride, cholesterol, interleukin (IL) -1β, IL-6 and tumor necrosis factor (TNF) -α levels in mice were investigated. Serum transaminase levels of 24-hr rubratoxin B-treated C3H/HeN mice were much higher than controls, indicating that rubratoxin B brought about hepatic injury. However, rubratoxin B-caused elevation was not remarkable in BALB/cAnN mice. Rubratoxin B decreased serum glucose level in mice of both strains. Again, rubratoxin B was less effective in BALB/cAnN mice. Serum triglyceride and cholesterol levels were not affected by rubratoxin B. We observed drastic elevation of serum IL-6 level in 24-hr rubratoxin B-treated C3H/HeN mice. On the other hand, we detected virtually no serum IL-6 in BALB/cAnN mice. In addition, serum IL -1β and TNF -α were not detected in mice of both strains. Taken together the above results, rubratoxin B exerted more toxicity and induced much more serum IL-6 in C3H/HeN mice than in BALB/AnN mice. It is likely that IL-6 is an excellent serological marker of the toxicity of rubratoxin B. Our results suggest that rubratoxin B can serve as a good model of drug-induced hepatic injury.

Protective effect of chromium(III) on acute lethal toxicity of carbon tetrachloride in rats and mice

Trivalent chromium (Cr(III)) preadministered intraperitoneally (5 mg Cr/kg body weight) to rats and mice protected these animals from acute lethal toxicity of carbon tetrachloride (CCl 4). Some other metals, Cr(VI), Cu(II), and Zn(II), had no effect on CCl 4 lethal toxicity. DL-α-tocopherol, one of the antioxidative agents, showed similar protective effects to Cr(III). Activities of serum GOT and GPT in mice were increased sharply by the administration of CCl 4, but these elevations were depressed by Cr(III) preadministration. Serum glucose levels of mice increased transiently after CCl 4 administration and then in the control group fell to hypoglycemic levels after 6 hr, whereas the Cr(III)-pretreated group kept to homeostatic levels. Lipid peroxidation of microsomes in mice 24 hr after Cr(III) administration was lower than that of the control. These results suggest that Cr(III) preadministered to mice might act as a radical scavenger to CCl 4 to form trichloromethyl radicals which are a major initial product of CCl 4 in liver cells.

Synthesis and Pharmacological Evaluation of Some Tosylbiurets and Tosylthiocarbamates as Potential Hypoglycemic Agents

The synthesis and preliminary pharmacological screening of some p-toluenesulfonyl-biurets and alkyl p-toluenesulfonylthiocarbamates are described. The biurets were prepared by refluxing tosyl isocyanate with the appropriate urea, and the thiocar-bamates were formed by the addition of selected mercaptans to the same isocyanate. None of the tosylbiurets possessed hypoglycemic activity; however, propyl tosyl-thiocarbamate lowered serum glucose levels in mice to approximately the same extent as tolbutamide.