• Journal of Applied Biological Chemistry
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• v.64 no.1
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• pp.89-96
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• 2021

The aim of this study is to examine the effect of Caulerpa okamurae ethanol extract (COE) on glucose metabolism and insulin sensitivity as one of the drug targets for treatment of type2 diabetes. COE significantly inhibited protein tyrosine phosphatase (PTP1B) and dipeptidyl peptidase-IV (DPP-IV) enzyme activities in vitro assay. Also, COE significantly enhanced the glucose uptake and the expression of insulin receptor substrate-1 (IRS-1) and glucose transporter4 (GLUT4) proteins in 3T3-L1 adipocytes or zebrafish larvae compared with control. In dexamethasone-induced resistance model of L6 myotubes, the protein expression of insulin signaling and glucose uptake was effectively increased by the treatment of COE. In contrast, the elevated phosphorylation of IRS-1 Ser307 was normally suppressed by treatment of COE. However, COE had no effect on insulin secretion in pancreatic beta cells. Thus, our results suggest that COE improves the glucose metabolism and insulin sensitivity through the regulation of insulin signaling and GLUT4 protein in insulin's target cells and zebrafish larvae.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.1033-1039
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• 2006

The metabolic response of Labeo rohita to thermal acclimation was assessed. Advanced fingerlings of L. rohita (average weight $31{\pm}1.4g$) were acclimated to 31, 33 and $36^{\circ}C$ compared with ambient temperatures ($26^{\circ}C$) for 30 days and different enzymes associated with stress response were estimated. Glycolytic enzyme-Lactate dehydrogenase, (LDH, E.C.1.1.1.27), TCA cycle enzyme-Malate dehydrogenase (MDH, E.C.1.1.1.37), Protein metabolizing enzymes-Aspartate amino transferase (AST, E.C.2.6.1.1) and Alanine amino transferase (ALT, E.C.2.6.1.2) of liver, gill and muscle, Gluconeogenic enzymes-Fructose 1,6 Bi phosphatase (FBPase, E.C. 3.1.3.11) and Glucose 6 phosphatase (G6Pase, E.C. 3.1.3.9) of liver and kidney were significantly (p<0.05) different with increasing acclimation temperatures. Heat Shock Protein-70 (HSP-70) was expressed in increasing intensity at 31, 33 and $36^{\circ}C$ but was not expressed at $26^{\circ}C$. Results suggest that higher acclimation temperatures enhance metabolism and L. rohita maintains homeostasis between $26-36^{\circ}C$ via an acclimation episode. Such adaptation appears to be facilitated by resorting to gluconeogenic and glycogenolytic pathways for energy mobilization and induction of HSPs.

• Korean Journal of Pharmacognosy
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• v.29 no.4
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• pp.374-378
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• 1998

Sodium arsenate and Paljin-Tang extract (PJT), a herbal restorative were treated p.o. 20 mg/kg and 500 mg/kg, respectively, and concurrently to rats, and examined the effects on the liver of rats. The values of protein, aniline hydroxylase (AH) and 2-thiobarbituric acid (TBA) were increased in arsenic-treated group. The values of glucose-6-phosphatase (G-6-P) and ${\delta}-aminolevulinic$ acid dehydratase (ALAD) of arsenic-treated group were decreased. But concurrent ad-ministration with PJT showed significant recovery from the toxicity of arsenic.

• Clinical and Experimental Pediatrics
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• v.48 no.8
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• pp.877-880
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• 2005

Purpose : Glycogen storage disease type Ia(GSD Ia) is an autosomal recessive disorder caused by the deficiency of glucose-6-phosphatase(G6Pase). The aim of the study was to investigate the spectrum of G6Pase gene mutations and relationship between genotype and clinical findings in Korean patients with GSD Ia. Methods : Genomic DNA was extracted from peripheral leukocytes of 20 patients with GSD Ia. The five exons of G6Pase gene were amplified and PCR products were directly sequenced. The frequency of short stature, hypoglycemia, hypercholesterolemia, hyperuricemia, hypercalciuria, nephrocalcinosis and hepatic adenoma was compared between 727G>T homozygotes and 727G>T compound heterozygotes. Results : A total of 5 different mutations were identified. The most common mutation was the 727G>T with an allele frequency of 80%. All patients were either homozygous(12/20) or heterozygous(8/20) for the 727G>T mutation. G122D was found in 3 patients, P178A in 1, G222R in 2, and S339R in 2. There was no difference in the frequency of short stature, hypoglycemia, hypercholesterolemia, hyperuricemia, nephrocalcinosis, and hepatic adenoma between 727G>T homozygotes and heterozygotes. Conclusion : Diagnosis of GSD Ia can be based on clinical and biochemical abnormalities combined with mutation analysis instead of enzymatic diagnosis that requires liver biopsy. Homozygosity for the 727G>T does not seem to alter the disease phenotype as compared with the heterozygous state.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.8
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• pp.1092-1098
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• 2011

The present study was conducted to investigate the effect of ${\beta}$-carotene on the antioxidant system of rats with diabetes. Forty Sprague Dawley rats were fed the AIN-76 control diet or the same diet supplemented with ${\beta}$-carotene (7.2 mg/kg diet) for 3 weeks, then diabetes was induced in half the rats by administering streptozotocin (45 mg/kg BW) into the femoral muscle. Diabetic and normal rats were fed the experimental diets for 2 more weeks. To investigate the effect of dietary ${\beta}$-carotene on diabetes, the activities of antioxidative enzymes and glutathione concentration were determined in normal and streptozotocin-induced diabetic rats. The plasma glucose levels in diabetic rats were not influenced by the dietary supplementation of ${\beta}$-carotene. Hepatic activities of catalase and superoxide dismutase in diabetic rats were significantly lower than those of control rats but ${\beta}$-carotene tended to induce these activities. Glutathione-S-transferase activity was not significantly different between experimental groups. Glucose-6-phosphatase activity was induced in diabetic rats, but dietary supplementation of ${\beta}$-carotene reduced this activity. The hepatic concentration of reduced glutathione in diabetic rats was lower than that of control rats, but dietary supplementation with ${\beta}$-carotene restored the content to some extent. These data suggest that diabetic rats are exposed to increased oxidative stress and that dietary supplementation with ${\beta}$-carotene may reduce its detrimental effects.

• BMB Reports
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• v.37 no.3
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• pp.370-375
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• 2004

There has been increasing interest in the value of using soybean to delay or reduce the tumor incidence. This study was undertaken to investigate the possible protective effects of soybean against hepatocarcinogenesis induced by DL-ethionine. Accordingly, we measured biochemical changes occurring in serum and liver of rats treated with DL-ethionine in the presence or absence of soybean. Male albino rats were fed a control diet containing the hepatocarcinogen, DL-ethionine, or the control diet plus soybean 30%, or the control diet plus soybean plus DL-ethionine 0.25% for three months and then returned to a control diet for up to nine months. Rats fed a control diet plus DL-ethionine showed a gradual decrease in liver DNA, RNA, total protein, and liver weight and enzyme activites of liver transaminases (GOT and GPT) and alkaline phosphatase over the 7-month study period. This was followed by a large increase in the liver parameters at the end of the $9^{th}$ month, except for 5'-nucleotidase and glucose-6-phosphatase that showed a large decrease. On the other hand, a gradual increase in the serum enzyme activities of GOT, GPT, 5-nucleotidase, alkaline phosphatase, and in the albumin/globulin (A/G) ratio is observed in the group of rats fed a control diet plus DL-ethionine compared to the control group over 8 months, and this was followed by a large increase in all serum parameters studied at nine-months. The administration of 30% soybean to the rat diet in addition to DL-ethionine maintained all parameters studied at near control values until the end of the $9^{th}$ month. This study suggests that soybean has a protective effect against the hepatocarcinogenesis induced by DL-ethionine.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.2
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• pp.227-233
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• 2003

Two experiments were conducted to evaluate the effects of chromium (Cr) on the growth performance, bone trait, serum traits, and immune responses in broilers. The broilers were fed corn-soybean meal basal diet supplemented with Cr at level of 0(control), 200, 400, or 800 ppb in the form of chromium picolinate (CrPic). The broilers were fed treated diets for 6 weeks in Exp. 1, but the Cr supplement was removed for the last 3 weeks in Exp. 2. Exp. 1 showed that dietary supplement of Cr did not affect growth performance of the broiler, though improved feed efficiency (p<0.05) was observed during 0 to 3 weeks. Moreover, serum total (p<0.05) and HDL cholesterols (p<0.06) were significantly higher in pooled Cr added group at 6 weeks of age, however, the difference was not significant in Exp. 2. The pooled Cr added group in Exp.1 had significantly lower (p<0.05) alkaline phosphatase activity and higher (p<0.09) calcium at 3 weeks. Significantly lower phosphorus was also observed in Exp. 2. With continued supplement of Cr as in Exp. 1, the alkaline phosphatase activity maintained higher at 6 weeks, as opposed to significantly lower in Exp. 2, which had no further Cr supplement. Higher bone breaking strength was observed in 400 ppb Cr supplemented in Exp. 1, though not significantly different. Serum glucose and triglyceride were not affected by Cr supplement. Antibody against Infectious Bronchitis (IB) was significantly (p<0.05) higher with 400 ppb Cr supplemented, and anti-Newcastle disease (ND) antibody also tended to be higher (p<0.06) in pooled Cr added group at 6 weeks of age in Exp. 1. Peripheral blood blastogenesis activity was not different among the treatments. The results suggest that diet supplemented with 400 ppb CrPic may be beneficial to the broiler.

• Nutrition Research and Practice
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• v.18 no.1
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• pp.46-61
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• 2024

BACKGROUND/OBJECTIVES: An increasing life expectancy in society has burdened healthcare systems substantially because of the rising prevalence of age-related metabolic diseases. This study compared the effects of animal protein hydrolysate (APH) and casein on metabolic diseases using aged mice. MATERIALS/METHODS: Eight-week-old and 50-week-old C57BL/6J mice were used as the non-aged (YC group) and aged controls (NC group), respectively. The aged mice were divided randomly into 3 groups (NC, low-APH [LP], and high-APH [HP] and fed each experimental diet for 12 weeks. In the LP and HP groups, casein in the AIN-93G diet was substituted with 16 kcal% and 24 kcal% APH, respectively. The mice were sacrificed when they were 63-week-old, and plasma and hepatic lipid, white adipose tissue weight, hepatic glucose, lipid, and antioxidant enzyme activities, immunohistochemistry staining, and mRNA expression related to the glucose metabolism on liver and muscle were analyzed. RESULTS: Supplementation of APH in aging mice resulted in a significant decrease in visceral fat (epididymal, perirenal, retroperitoneal, and mesenteric fat) compared to the negative control (NC) group. The intraperitoneal glucose tolerance test and area under the curve analysis revealed insulin resistance in the NC group, which was alleviated by APH supplementation. APH supplementation reduced hepatic gluconeogenesis and increased glucose utilization in the liver and muscle. Furthermore, APH supplementation improved hepatic steatosis by reducing the hepatic fatty acid and phosphatidate phosphatase activity while increasing the hepatic carnitine palmitoyltransferase activity. Furthermore, in the APH supplementation groups, the red blood cell (RBC) thiobarbituric acid reactive substances and hepatic H₂O₂ levels decreased, and the RBC glutathione, hepatic catalase, and glutathione peroxidase activities increased. CONCLUSIONS: APH supplementation reduced visceral fat accumulation and alleviated obesity-related metabolic diseases, including insulin resistance and hepatic steatosis, in aged mice. Therefore, high-quality animal protein APH that reduces the molecular weight and enhances the protein digestibility-corrected amino acid score has potential as a dietary supplement for healthy aging.

• Journal of Yeungnam Medical Science
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• v.36 no.1
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• pp.26-35
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• 2019

Background: Dysregulation of hepatic glucose production (HGP) contributes to the development of type 2 diabetes mellitus. Telmisartan, an angiotensin II type 1 receptor blocker (ARB), has various ancillary effects in addition to common blood pressure-lowering effects. The effects and mechanism of telmisartan on HGP have not been fully elucidated and, therefore, we investigated these phenomena in hyperglycemic HepG2 cells and high-fat diet (HFD)-fed mice. Methods: Glucose production and glucose uptake were measured in HepG2 cells. Expression levels of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase ${\alpha}$ ($G6Pase-{\alpha}$), and phosphorylation levels of insulin receptor substrate-1 (IRS-1) and protein kinase C ${\zeta}$ ($PKC{\zeta}$) were assessed by western blot analysis. Animal studies were performed using HFD-fed mice. Results: Telmisartan dose-dependently increased HGP, and PEPCK expression was minimally increased at a $40{\mu}M$ concentration without a change in $G6Pase-{\alpha}$ expression. In contrast, telmisartan increased phosphorylation of IRS-1 at Ser302 ($p-IRS-1-Ser^{302}$) and decreased $p-IRS-1-Tyr^{632}$ dose-dependently. Telmisartan dose-dependently increased $p-PKC{\zeta}-Thr^{410}$ which is known to reduce insulin action by inducing IRS-1 serine phosphorylation. Ectopic expression of dominant-negative $PKC{\zeta}$ significantly attenuated telmisartan-induced HGP and $p-IRS-1-Ser^{302}$ and -inhibited $p-IRS-1-Tyr^{632}$. Among ARBs, including losartan and fimasartan, only telmisartan changed IRS-1 phosphorylation and pretreatment with GW9662, a specific and irreversible peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$) antagonist, did not alter this effect. Finally, in the livers from HFD-fed mice, telmisartan increased $p-IRS-1-Ser^{302}$ and decreased $p-IRS-1-Tyr^{632}$, which was accompanied by an increase in $p-PKC{\zeta}-Thr^{410}$. Conclusion: These results suggest that telmisartan increases HGP by inducing $p-PKC{\zeta}-Thr^{410}$ that increases $p-IRS-1-Ser^{302}$ and decreases $p-IRS-1-Tyr^{632}$ in a $PPAR{\gamma}$-independent manner

• Journal of the Korean Society of Food Culture
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• v.19 no.4
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• pp.419-428
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• 2004

The Purpose of this study was to investigate the effect of dietary sea tangle in diabetic rats treated with streptozotocin(STZ). Four groups of rats (Sprague-Dawley male rats,180-200g) were normal rats fed control diet(C), diabetic rats fed control diet(CD), normal rats fed sea tangl diet(T), and diabetic ,rats fed sea tangle diet(TD), diabetes was induced by single injection of streptozotocin(60mg/kg B.W.). High density lipoprotein(HDL) of T and TD group were higher than other groups(C and T groups). And the weekly change of blood sugar was decreased in the 3th and 4th weeks. But serum triglyceride (TG) of diabetic rats fed sea tangle diet(TD) was lower than diabetic rats fed control dlet(CD). Activity of hepatic microsomal Glucose 6-phosphatase(G6Pase) was significantly increased CD and TD groups higher than C and T groups. Hepateic glutathione S-transferase(GST of T, CD and TD groups were significantly lower than C group(p<0.05), glutathione peroxidase (GPX) of T and TD groups were significantly higher than C and CD groups(p<0.05).