BACKGROUND: Periploca aphylla is used by local population and indigenous medicine practitioners as stomachic, tonic, antitumor, antiulcer, and for treatment of inflammatory disorders. The aim of this study was to evaluate antidiabetic effect of the extract of P. aphylla and to investigate antioxidant and hypolipidemic activity in streptozotocin (STZ)-induced diabetic rats. METHODS: The present research was conducted to evaluate the antihyperglycemic potential of methanol extract of P. aphylla (PAM) and subfractions n-hexane (PAH), chloroform (PAC), ethyl acetate (PAE), n-butanol (PAB), and aqueous (PAA) in glucose-overloaded hyperglycemic Sprague-Dawley rats. Based on the efficacy, PAB (200 mg/kg and 400 mg/kg) was tested for its antidiabetic activity in STZ-induced diabetic rats. Diabetes was induced via intraperitoneal injection of STZ (55 mg/kg) in rat. Blood glucose values were taken weekly. HPLC-DAD analysis of PAB was carried out for the presence of various polyphenols. RESULTS: HPLC-DAD analysis of PAB recorded the presence of rutin, catechin, caffeic acid, and myricetin. Oral administration of PAB at doses of 200 and 400 mg/kg for 21 days significantly restored (P < 0.01) body weight (%) and relative liver and relative kidney weight of diabetic rats. Diabetic control rats showed significant elevation (P < 0.01) of AST, ALT, ALP, LDH, total cholesterol, triglycerides, LDL, creatinine, total bilirubin, and BUN while reduced (P < 0.01) level of glucose, total protein, albumin, insulin, and HDL in serum. Count of blood cells and hematological parameters were altered in diabetic rats. Further, glutathione peroxidase, catalase, superoxide dismutase, glutathione reductase, and total soluble protein concentration decreased while concentration of thiobarbituric acid reactive substances and percent DNA damages increased (P < 0.01) in liver and renal tissues of diabetic rats. Histopathological damage scores increased in liver and kidney tissues of diabetic rats. Intake of PAB (400 mg/kg) resulted in significant improvement (P < 0.01) of above parameters, and results were comparable to that of standard drug glibenclamide. CONCLUSION The result suggests the antihyperglycemic, antioxidant, and anti-inflammatory activities of PAB treatment in STZ-compelled diabetic rat. PAB might be used as new therapeutic agent in diabetic patients to manage diabetes and decrease the complications.
1-Butanol/chemistry* ; Administration, Oral ; Animals ; Diabetes Mellitus, Experimental/drug therapy* ; Dose-Response Relationship, Drug ; Hypoglycemic Agents/chemistry* ; Male ; Periploca/chemistry* ; Phytochemicals/chemistry* ; Plant Extracts/chemistry* ; Rats ; Rats, Sprague-Dawley ; Streptozocin/adverse effects*

OBJECTIVE: The present study aims at determining the stability of a popular type 2 diabetes rat model induced by a high-fat diet combined with a low-dose streptozotocin injection. METHODS: Wistar rats were fed with a high-fat diet for 8 weeks followed by a one-time injection of 25 or 35 mg/kg streptozotocin to induce type 2 diabetes. Then the diabetic rats were fed with regular diet/high-fat diet for 4 weeks. Changes in biochemical parameters were monitored during the 4 weeks. RESULTS: All the rats developed more severe dyslipidemia and hepatic dysfunction after streptozotocin injection. The features of 35 mg/kg streptozotocin rats more resembled type 1 diabetes with decreased body weight and blood insulin. Rats with 25 mg/kg streptozotocin followed by normal diet feeding showed normalized blood glucose level and pancreatic structure, indicating that normal diet might help recovery from certain symptoms of type 2 diabetes. In comparison, diabetic rats fed with high-fat diet presented decreased but relatively stable blood glucose level, and this was significantly higher than that of the control group (P<0.05). CONCLUSIONS This model easily recovers with normal diet feeding. A high-fat diet is suggested as the background diet in future pharmacological studies using this model.
Animals ; Blood Glucose ; metabolism ; Diabetes Mellitus, Experimental ; blood ; etiology ; physiopathology ; Diabetes Mellitus, Type 2 ; blood ; etiology ; physiopathology ; Diet, High-Fat ; adverse effects ; Insulin ; blood ; Lipids ; blood ; Liver ; drug effects ; pathology ; physiopathology ; Male ; Malondialdehyde ; blood ; Oxidative Stress ; Rats ; Rats, Wistar ; Streptozocin ; administration & dosage ; toxicity ; Superoxide Dismutase ; blood ; Uric Acid ; blood

Due to the multifactorial and multisystemic nature of diabetes mellitus, it is often treated with a combination of therapeutic agents having different mode of action. Earlier, we have synthesized several organozinc complexes and evaluated their safety and antidiabetic properties in experimental type 2 diabetes mellitus (T2DM). More recently, we have synthesized a metformin-3-hydroxyflavone complex and studied its antidiabetic efficacy in experimental rats. In the present study, a new zinc-mixed ligand (metformin-3-hydroxyflavone) was synthesized, characterized by spectral studies and its antidiabetic properties was evaluated in HFD fed—low dose streptozotocin induced T2DM in rats. The hypoglycemic efficacy of the complex was evaluated through oral glucose tolerance test, homeostasis model assessment of insulin resistance, quantitative insulin sensitivity check index and by determining the status of important biochemical parameters. Oral administration of the complex at a concentration of 10 mg/kg body weight/rat/day for 30 days significantly improved the glucose homeostasis. The complex possesses significant antidiabetic properties relatively at a less concentration than metformin-3-hydroxyflavone complex in ameliorating hyperglycemia.
Administration, Oral ; Animals ; Diabetes Mellitus ; Diabetes Mellitus, Type 2 ; Diet, High-Fat* ; Glucose ; Glucose Tolerance Test ; Homeostasis ; Hyperglycemia ; Hypoglycemic Agents ; Insulin Resistance ; Metformin ; Rats* ; Streptozocin* ; Zinc

OBJECTIVEAnabasis aretioides (Coss & Moq.), a Saharan plant belonging to Chenopodiaceae family, is widely distributed in semi-desert areas from the Tafilalet region of Morocco. This plant is extensively used by local population against diabetes and cardiovascular disorders. The purpose of the study was to investigate the effect of the aqueous A. aretioides extract on lipid metabolism in normal and streptozotocin (STZ)-induced diabetic rats and to identify the polyphenolic compounds present. In addition, the in vitro antioxidant activity of the aqueous A. aretioides extract was also evaluated.

METHODSThe effect of an aerial part aqueous extract (APAE) of A. aretioides (5 mg/kg of lyophilized A. aretioides APAE) on plasma lipid profile was investigated in normal and STZ-induced diabetic rats (n = 6) after once daily oral administration for 15 days. The aqueous extract was tested for its 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity. Polyphenolic compounds in the extracts were definitively characterized by high-performance liquid chromatography-diode array detection-electrospray ionization-mass spectrometry.

RESULTSIn diabetic rats, oral administration of A. aretioides APAE provoked a significant decrease in both plasma cholesterol and triglyceride levels from the first to the second week (P < 0.01). A significant decrease on plasma triglyceride levels was also observed in normal rats (P < 0.01), where the reduction was 53%. In addition, the phytochemical analysis revealed the presence of 12 polyphenolic compounds. Moreover, according to the DPPH radical-scavenging activity, the aqueous extract showed an in vitro antioxidant activity.

CONCLUSIONAqueous A. aretioides APAE exhibits lipid-lowering and in vitro antioxidant activities. Many polyphenols were present in this extract and these phytoconstituents may be involved in the pharmacological activity of this plant.

Animals ; Antioxidants ; administration & dosage ; Chenopodiaceae ; chemistry ; Cholesterol ; blood ; Chromatography, High Pressure Liquid ; Diabetes Mellitus, Experimental ; blood ; drug therapy ; Humans ; Hypolipidemic Agents ; administration & dosage ; chemistry ; Male ; Phytochemicals ; administration & dosage ; chemistry ; Plant Extracts ; administration & dosage ; chemistry ; Polyphenols ; administration & dosage ; chemistry ; Rats ; Rats, Wistar ; Streptozocin ; Tandem Mass Spectrometry ; Triglycerides ; blood

To determine the effect of the tumor necrosis factor-α (TNF-α) in odontoclast formation, we administrated a TNF-α inhibitor in rats with diabetes rats with periodontitis. The rats included in the study were divided into three groups: control rats without diabetes or periodontitis (the C group), rats with periodontitis and diabetes (the PD group), and rats with periodontitis and diabetes treated by infliximab, the TNF inhibitor (the PD+infliximab group). The PD and PD+ infliximab groups received intravenous administrations of streptozotocin (STZ, 50 mg/kg) to induce diabetes. After 7 days of STZ injections, the mandibular first molars were ligatured to induce periodontitis. The PD+infliximab group was intrapenitoneally administrated by infliximab (5 mg/kg). On days 3 and 20 after the ligature administration, odontoclast formation along root surfaces was evaluated by tartrate resistant acid phosphatase (TRAP) staining and cathepsin K immunohistochemistry. On day 3, the number of TRAP- and cathepsin K-positive cells increased more so in the PD group than in the C group. The PD+infliximab group showed a lower number of positive cells than the PD group. There was no difference in all the groups on day 20. On day 3, the cathepsin-K positive multinucleated and mononucleated cells were higher in the PD group than in the C group. The number of cathepsin-K positive multinucleated cells was lower in the PD+infliximab group than in the PD group. The PD group showed more cathepsin K-positive cells in the furcation and distal surfaces than the c group. The Cathepsin K-positive cells of the PD+infliximab group were lower than that of the PD group in furcation. These results suggest that TNF-α stimulates odontoclast formation in diabetes with periodontitis.
Acid Phosphatase ; Administration, Intravenous ; Animals ; Cathepsin K ; Cathepsins ; Immunohistochemistry ; Infliximab ; Ligation ; Molar ; Necrosis ; Osteoclasts* ; Periodontitis* ; Rats* ; Streptozocin

The present study aimed at determining whether berberine can enhance the antidiabetic effects and alleviate the adverse effects of canagliflozin in diabetes mellitus. Streptozotocin-induced diabetic mice were introduced, and the combined effects of berberine and canagliflozin on glucose metabolism and kidney functions were investigated. Our results showed that berberine combined with canagliflozin (BC) increased reduction of fasting and postprandial blood glucose, diet, and water intake compared with berberine or canagliflozin alone. Interestingly, BC showed greater decrease in blood urea nitrogen and creatinine levels and lower total urine glucose excretion than canagliflozin alone. In addition, BC showed increased phosphorylated 5' AMP-activated protein kinase (pAMPK) expression and decreased tumor necrosis factor alpha (TNFα) levels in kidneys, compared with berberine or canagliflozin alone. These results indicated that BC was a stronger antidiabetic than berberine or canagliflozin alone with less negative side effects on the kidneys in the diabetic mice. The antidiabetic effect was likely to be mediated by synergically promoting the expression of pAMPK and reducing the expression of TNFα in kidneys. The present study represented the first report that canagliflozin combined with berberine was a promising treatment for diabetes mellitus. The exact underlying mechanisms of action should be investigated in future studies.
AMP-Activated Protein Kinases ; metabolism ; Animals ; Berberine ; administration & dosage ; Blood Glucose ; metabolism ; Canagliflozin ; administration & dosage ; adverse effects ; Diabetes Mellitus, Experimental ; drug therapy ; metabolism ; Drug Therapy, Combination ; Drugs, Chinese Herbal ; administration & dosage ; Humans ; Hypoglycemic Agents ; administration & dosage ; Insulin ; metabolism ; Kidney ; drug effects ; enzymology ; metabolism ; Male ; Mice ; Streptozocin

Diabetic nephropathy (DN) is a common and serious clinical complication of diabetes and presently there are no effective ways to prevent its occurrence and progression. Recent studies show that pentoxifylline (PTX) can improve renal hemodynamics, reduce urinary protein excretion, and alleviate or delay renal failure in DN patients. In this study, we focused on the anti-oxidative stress effect of PTX on alleviating renal damages of DN using rat models. DN rats were established with injection of streptozotocin. Blood glucose, urinary protein excretion, serum cystatin C, renal biopsy, superoxide dismutase (SOD) and malondialdehyde (MDA) in serum and renal homogenate and renal nitrotyrosine levels were analyzed before and 12 weeks after the treatment of PTX. Before treatment, all the DN rats had elevated blood glucose, increased urinary protein excretion and elevated serum cystatin C. Morphologically, DN rats exhibited renal tissue damages, including swelling and fusions of foot processes of podocytes under electron microscope. Masson staining revealed blue collagen deposition in glomeruli and renal interstitium. With treatment of PTX, symptoms and renal pathological changes of DN rats were alleviated. Furthermore, the MDA levels were increased and the SOD levels were decreased in the serum and kidneys of DN rats, and these changes were reversed by PTX. The expression of nitrotyrosine was up-regulated in DN rat model and down-regulated by PTX, indicating that PTX was able to inhibit oxidative reactions in DN rats. PTX could alleviate renal damage in DN, which may be attributable to its anti-oxidative stress activity.
Animals ; Biomarkers ; analysis ; Diabetes Mellitus, Experimental ; drug therapy ; pathology ; Diabetic Nephropathies ; drug therapy ; metabolism ; pathology ; Gene Expression Regulation ; drug effects ; Kidney ; metabolism ; pathology ; Malondialdehyde ; blood ; Oxidative Stress ; drug effects ; Pentoxifylline ; administration & dosage ; pharmacology ; Rats ; Streptozocin ; Superoxide Dismutase ; metabolism ; Tyrosine ; analogs & derivatives ; metabolism

OBJECTIVETo determine the optimal dosing of streptozotocin (STZ) for establishing lymphoma-bearing diabetic mouse models.

METHODSA total of 200 healthy male Balb/c mice were randomized into 4 groups (n=50) for intraperitoneal injection of a single dose of vehicle solution (control) or 75, 150, or 200 mg/kg STZ. The changes of body weight and blood glucose were observed regularly, and the success rate of modeling, mortality rate, and survival of the mice were recorded after the injections. The mice with successfully induced diabetes received subcutaneous or tail vein injection of A20 lymphoma cells, and the rate of tumorigenesis, mortality rate, and survival time were observed at 1 month and 3 months after tumor cell injection.

RESULTSCompared with the control group, the mice receiving STZ injection at 150 and 200 mg/kg showed significantly decreased body weight and increased blood glucose (P<0.05), while STZ at 75 mg/kg did not produced such obvious changes. STZ injection at 200 mg/kg resulted in a significantly higher mortality rate and shorter survival time than STZ at 150 mg/kg (P<0.05). In the control group and 150 and 200 mg/kg STZ groups, the rate of tumorigenesis or mortality rate showed no significant differences after subcutaneous injection of A20 lymphoma cells (P>0.05), but differed significantly at 3 months after tail vein injection of the tumor cells (P<0.05).

CONCLUSIONIntraperitoneal injection of STZ at 150 mg/kg is associated with a low mortality rate, a high successful modeling rate of diabetes and a long survival time in mice, and is therefore optimal for establishing diabetic mouse models bearing transplanted tumors.

Animals ; Blood Glucose ; Body Weight ; Diabetes Mellitus, Experimental ; Diabetes Mellitus, Type 2 ; chemically induced ; Injections ; Male ; Mice ; Mice, Inbred BALB C ; Streptozocin ; administration & dosage

OBJECTIVETo establish a blood glucose fluctuation model in diabetic rats.

METHODSMale SD rats were randomly divided into 2 groups, namely normal group and diabetes group. Rat model of diabetes was established by single intraperitoneal injection of streptozotocin (STZ) and then divided into sustained high blood glucose group and blood glucose fluctuation group. Rat model of blood glucose fluctuation was established by subcutaneous injection with regular insulin or gavaging of glucose twice daily in diabetic rats. The general condition, body weight, daily blood glucose levels of 5 different times, daily average blood glucose (MBG), standard deviation of daily average blood glucose (SDBG), the maximum amplitude of glycemic excursions (LAGE), fasting serum insulin (FINS) and pancreatic tissue pathology were observed.

RESULTSRats in blood glucose fluctuation group and sustained high blood glucose group developed symptoms of polyphagia, polyuria and polydipsia. Though significant differences in body weight were observed at different time (P<0.01), no significant differences were found among the three groups (P>0.05). After 6 weeks of blood glucose fluctuation, MBG, SDBG and LAGE in blood glucose fluctuation group and sustained high blood glucose group were increased significantly than those in normal group (P<0.01), the level of FINS decreased markedly (P<0.05). SDBG and LAGE in blood glucose fluctuation group were higher than those in sustained high blood glucose group (P<0.01). Islet of diabetic rat became atrophy, irregular shape, sparse distribution, and decreased in number, and the changes were more obvious in blood glucose fluctuation group.

CONCLUSIONRat model of blood glucose fluctuation can be successfully established by subcutaneous injection of regular insulin of gavage of glucose twice daily in diabetic rats.

Animals ; Blood Glucose ; analysis ; Body Weight ; Diabetes Mellitus, Experimental ; Fasting ; Glucose ; administration & dosage ; Insulin ; administration & dosage ; Male ; Rats ; Rats, Sprague-Dawley ; Streptozocin

OBJECTIVETo study the effects of Xixin decoction (XXD) on O-GlcNAc transferase (OGT) and O-GlcNAc glycosidase in O-GlcNAc glycosylation of tau proteins in the brain of rats with sporadic Alzheimer's disease (SAD) and explore the possible mechanism.

METHODSMale SD rats were randomly divided into sham-operated group, model group, donepezil group, and low-, moderate-, and high-dose XXD groups. After treatment and behavioral test, the rats were sacrificed for detecting the expressions of OGT and O-GlcNAc glycosidase in the brain using immunohistochemistry and Western blotting.

RESULTSXXD significantly enhanced the expressions of OGT in the hippocampus of SAD rats and lowered the expression of O-GlcNAc glycosidase (P<0.05 or 0.01). OGT and O-GlcNAc glycosidase expressions showed no significant differences between the model group and donepezil group (P>0.05).

CONCLUSIONXXD can regulate the expression of OGT and O-GlcNAc glycosidase to enhance O-GlcNAc glycosylation of tau proteins in the hippocampus of SAD rats.

Acetylglucosaminidase ; metabolism ; Alzheimer Disease ; chemically induced ; enzymology ; metabolism ; Animals ; Dose-Response Relationship, Drug ; Drugs, Chinese Herbal ; administration & dosage ; pharmacology ; Glycosylation ; Hippocampus ; enzymology ; metabolism ; Male ; N-Acetylglucosaminyltransferases ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Streptozocin ; tau Proteins ; metabolism