• Archives of Pharmacal Research
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• v.26 no.11
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• pp.979-983
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• 2003

The pharmacokinetic of tolbutamide was studied after the oral administration to normal rabbits or rabbits with mild to medium folate-induced renal failure. The plasma concentrations of tolbutamide were significantly elevated (p<0.05) during 9 to 24 h in rabbits with mild or medium folate-induced renal failure. Consequently, the area under the plasma concentration-time curves (AUC) was significantly higher in mild (p<0.05) and medium (p<0.01) folate-induced renal failure rabbits (i.e., 2906 $\mu$g/mL$.$h for mild renal failure and 4074 $\mu$g/mL$.$h for moderate renal failure) than that in normal rabbits (i.e., 2295 $\mu$g/mL$.$h). The cumulative urinary excretion of tolbutamide was significantly depressed (p<0.05) in medium folate-induced renal failure rabbits (i.e., 3.3 mg) compared with that in normal rabbits (i.e., 5.9 mg). The elimination rate constant (Kel) of tolbutamide was significantly decreased in medium renal failure rabbits (i.e., 0.027 $h^{-1}$) than that in normal rabbits (i.e., 0.044 $h^{-1}$ ); As a result, the terminal half-life of tolbutamide in medium folate-induced renal failure rabbits (i.e., 25.5 h) was significantly longer (p<0.01) than that in normal rabbits (i.e., 15.7 h). The change in pharmacokinetic parameters is consistent with the hypothesis that the alteration is mediated by the depressed metabolic elimination of the drug by the induction of renal failure. Therefore, these observations indicated that the dosage adjustment may be necessary for tolbutamide in patients with renal insufficiency.

• Journal of Pharmaceutical Investigation
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• v.30 no.2
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• pp.107-112
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• 2000

The changes in pharmacokinetic parameters of tolbutamide, such as the area under the plasma concentration-time curve from time zero to time infinity (AUC) and elimination rate constant (Kel) were evaluated after oral administration of the drug to rabbits with acute and chronic alloxan-induced diabetes mellitus (AIDRs). After oral administration, the plasma concentrations of tolbutamide were significantly higher between 9 and 12 hr in chronic AIDRs compared with these in control rabbits. Therefore, the AUC was significantly greater in chronic AIDRs $(3,490{\pm}649\;versus\;5,020{\pm}1,030{\mu}gml{\cdot}hr)$. This could be due to inhibition of tolbutamide metabolism by liver in AIDRs since tolbutamide is essentially completely metabolized in liver. Impaired liver and kidney function in AIDRs were based on blood chemistry and tissue microscopy. The absorption rate constant and Kel were significantly slower in chronic AIDRs compared with those in control rabbits.

• YAKHAK HOEJI
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• v.36 no.6
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• pp.518-528
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• 1992

To determine the optimal conformation of sulfonylureas, the correlation between conformation and hypoglycemic activity of the two sulfonylureas of tolbutamide and chlorpropamide as hypoglycemic agent was studied using an empirical potential function (ECEPP/2) and the hydration shell model in the unhydrated and hydrated states. The conformational energy was minimized from several starting conformations with possible torsion angles in each molecule. The conformational entropy change of each conformation was computed using a harmonic approximation. To understand the hydration effect on the conformation of the molecules in aqueous solution, the contribution of water-accessible volume of each group or atom in the lowest-free-energy conformation was calculated and compared each other. From comparison of the computed lowest-free-energy conformations of two sulfonylureas, it could be suggested that the hydration of sulfonylurea moiety is related to increase the hypoglycemic activity. From the calculation results, it was known that the conformational entropy is the major contribution to stabilize the low-free-energy conformations of two sulfonylureas in unhydrated state. Whereas, in hydrated state, the hydration free energy largely contributes to the total free energies of low-free-energy conformations of tolbutamide and conformational entropy contributes to stabilize the low-free-energy conformations of chlorpropamide. The torsion angles from phenyl ring to urea moiety of the low-free-energy conformations of the two sulfonylureas were shown the nearly regular trend. On the basis of these results, the conformation exhibiting the optimal hypoglycemic activity of sulfonylureas and the binding direction to pancreatic receptor site A could be predicted. Also, according to the side chain lengthening of urea moiety, tolbutamide showed various conformational change. Therefore, steric effect may be important factor in the interaction between sulfonylureas and the putative pancreatic receptor.

• Preventive Nutrition and Food Science
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• v.18 no.3
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• pp.169-174
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• 2013

The acute and subacute hypoglycemic and antihyperglycemic effects of drinkable ripe onion juice (Commercial product name is "Black Onion Extract") were investigated in normal and streptozotocin-induced diabetic rats. For tests of acute and subacute hypoglycemic effects, ripe onion juice (5 and 15 mL/kg b.w.) was administered by oral gavage to normal Sprague Dawley rats and measurements of fasting glucose levels and oral glucose tolerance tests were performed. Tolbutamide was used as a reference drug at a single oral dose of 250 mg/kg b.w. To test anti-hyperglycemic activity, the ripe onion juice was administered to streptozotocin-induced diabetic rats by oral gavage at single dose of 15 mL/kg b.w. per day for 7 consecutive days. Oral administration of the ripe onion juice at either dosed level of 5 or 15 mL/kg b.w. showed no remarkable acute hypoglycemic effect in normal rats. The two dosed levels caused a relatively small reduction, only 18% and 12% (5 and 15 mL/kg b.w., respectively) decrease in glucose levels at 2 h after glucose loading in normal rats. However, at 3 h after glucose loading, blood glucose levels in the ripe onion juice-dosed rats were decreased to the corresponding blood glucose level in tolbutamide-dosed rats. Although showing weak hypoglycemic potential compared to that of tolbutamide, oral administration of ripe onion juice (15 mL/kg b.w.) for a short period (8 days) resulted in a slight reduction in the blood glucose levels that had elevated in Streptozotocin-induced diabetic rats. In conclusion, these results suggest that the commercial product "Black Onion Extract" may possess antihyperglycemic potential in diabetes.

• Membrane Journal
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• v.23 no.4
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• pp.297-303
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• 2013

Diagnostic membranes which were made of polyphosphazenes were prepared for the measurements of blood glucose concentration. The effects of possible interferents in human blood on the glucose concentration measurements were examined. Above those interferents, ascorbic acid (AA) showed 3~9% higher K/S values compared to the standard plasma solution, tolbutamide (TA) showed 11~13% lower K/S values than those of plasma, triglycerides and bovine serum albumin (BSA) showed 20~25% lower K/S values than those of plasma. However, most of the interferents except above materials did not show any serious effects on the blood glucose measurements.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2002.07a
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• pp.219-219
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• 2002

The SPP003 is a mixture of water extract from Schizandrae Fructus, Poligoni multiflori Radix, Ginseng Radix Akba and Hoelen. The aim of this study was to investigate the anti-hyperglycemic effect of SPP003 in normal and streptozotocin (STZ)-induced diabetic rats, and to monitor the toxicity of SPP003. Oral glucose tolerance test (OGTT) was performed after oral administration of SPP003 100, 300, 600 and 900 mg/kg in normal rats. Blood glucese concentration was measured at -30 min (vehicle, SPP003 or tolbutamide 60 mg/kg, 0 min (glucose treatment), 60, 120 and 180 min. Rats were administerd STZ 65mg/kg (0.1M citrate buffer, pH 4.5) intraperitoneally to induce diabetes and administered vehicle, Spp003 (100, 300 and 600 mg/kg) or tolbutamide (60 mg/kg) orally once a day for 4 weeks. Blood glucose level was measured a 0, 4, 7, 14, 21 and 29 day after initial drug administration. A single oral toxicity of SPP003 was studied in Sprague-Dawley rats of both sexes. In this study, rats were administered with doses of 1, 2 and 5 g/kg of SPP003. In glucose tolerance test, SPP003 900 mg/kg markedly decreased glucose concentration at 1 hr after glucose treatment. Blood glucose levels were much higher in STZ-diabetic rats. These increases were significantly attenuated by SPP003 600 mg/kg. SPP003 did not show any signigicant toxicity. These findings suggest that SPP003 has hypoglycemic properties in STZ-diabetic rats.

• Toxicological Research
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• v.22 no.1
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• pp.1-8
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• 2006

The primary metabolism of pyribenzoxim was studied in rat liver microsomes in order to identify the cytochrome P450 (CYP) isoform(s) and esterases involved in the metabolism of pyribenzoxim. Chemical inhibition using CYP isoform-selective inhibitors such as ${\alpha}$-naphthoflavone, tolbutamide, quinine, chlorzoxazone, troleandomycin, and undecynoic acid indicated that CYP1A and CYP2D are responsible for the oxidative metabolism of pyribenzoxim. And inhibitory studies using eserine, bis-nitrophenol phosphate, dibucaine, and mercuric chloride indicated pyribenzoxim hydrolysis involved in microsomal carboxylesterases containing an SH group (cysteine) at the active center.

• Natural Product Sciences
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• v.7 no.4
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• pp.107-109
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• 2001

To investigate anti-diabetic component from the node of lotus rhizome (Nelumbo nucifera; Nymphaeaceae), activity guided isolation was conducted. One amino acid was isolated from active fraction of the aqueous methanolic extract. The structure of this compound was identified as tryptophan (1) by the analysis of spectroscopic evidences and comparisons with the data of authentic samples. Tryptophan reduced the blood glucose level significantly in glucose-fed hyperglycemic mice compared with glucose-treated group and exhibited 44.3% of activity compared with tolbutamide,.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.198-198
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• 2001

No report has been addressed to the CYP isoforms catalyzing chlorpropamide, a structural analogue of tolbutamide. To evaluate enzyme(s) mediating formation of 2-hydroxycWorpropamide, a major metabolite and identified by LC/Mass and NMR, incubation studies using human liver microsomes and cDNA expressed CYP were performed on the presence or absence of selective inhibitors of each CYP isoform. (omitted)

• Journal of Life Science
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• v.27 no.11
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• pp.1269-1275
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• 2017

Tenebrio molitor samples were investigated as novel biomaterials and sources of food in several recent studies. However, the insects' effects on hair growth were not sufficiently researched. To develop novel and natural materials for preventing alopecia and promoting hair growth, this study investigated the antioxidant activities and hair-growth promotion effects of TMEs. To determine the antioxidant activities, the TMEs' DPPH radical- and nitrite-scavenging activities were examined. To determine hair-growth promotion effects, proliferations of human dermal papilla cells (DPCs) and the murine fibroblast cell line NIH3T3 were evaluated by using an MTS assay. In addition, estimations were made for cell viabilities against cell death induced by dihydrotesterone (DHT) in DPCs and inhibitory effects against potassium channel blocking induced by tolbutamide (TBM) in NIH3T3 cells. The DPPH radical scavenging activity was 81.17%, and the nitrite scavenging activity was 43.69%; the activities were similar to the activities of blueberry extracts. Moreover, the TMEs promoted the proliferation of human DPCs and NIH3T3 cells, which were concentrated dependently. The TMEs prevented not only DHT-induced DPC cytotoxicity but also TBM's action as a potassium channel blocker in NIH3T3 cells. The results suggested that TME could be used as a functional therapeutic alopecia reagent, to prevent hair loss and to promote hair growth.