• Journal of Ginseng Research
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• v.47 no.3
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• pp.420-428
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• 2023

Background: Ginsenoside F2 (GF2), a minor component of Panax ginseng, has been reported to possess a wide variety of pharmacological activities. However, its effects on glucose metabolism have not yet been reported. Here, we investigated the underlying signaling pathways involved in its effects on hepatic glucose. Methods: HepG2 cells were used to establish insulin-resistant (IR) model and treated with GF2. Cell viability and glucose uptake-related genes were also examined by real-time PCR and immunoblots. Results: Cell viability assays showed that GF2 up to 50 μM did not affect normal and IR-HepG2 cell viability. GF2 reduced oxidative stress by inhibiting phosphorylation of the mitogen-activated protein kinases (MAPK) signaling components such as c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase 1/2 (ERK1/2), and p38 MAPK, and reducing the nuclear translocation of NF-κB. Furthermore, GF2 activated PI3K/AKT signaling, upregulated the levels of glucose transporter 2 (GLUT-2) and GLUT-4 in IR-HepG2 cells, and promoted glucose absorption. At the same time, GF2 reduced phosphoenolpyruvate carboxykinase and glucose-6-phosphatase expression as well as inhibiting gluconeogenesis. Conclusion: Overall, GF2 improved glucose metabolism disorders by reducing cellular oxidative stress in IR-HepG2 cells via MAPK signaling, participating in the PI3K/AKT/GSK-3β signaling pathway, promoting glycogen synthesis, and inhibiting gluconeogenesis.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.689-695
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• 1996

In order to prove physiological function of ${\beta}-Glucan$ isolated from barley flour by enzymatic method, in vitro experiments simulating the passive membrane transport of gastrointestinal tract were carried out using dialysis membrane. The yield of ${\beta}-Glucan$ from barley flour was $6.2{\%}$ and its constituents were determined to give $81.6{\%}$ total dietary fiber, $72.9{\%}$ soluble dietary fiber, $8.7{\%}$ insoluble dietary fiber, $8.5{\%}$ moisture, $2.5{\%}$ protein and $7.4{\%}$ ash. The water holding capacity of the ${\beta}-Glucan$ preparation was 6 g water/g dry material. The glucose retardation index after 30 minute dialysis was $13.5{\%}$ in the presence of $3{\%}$ ${\beta}-Glucan$. As the dialysis period became longer, the retarding effect toward glucose absorption decreased and the effect was close to zero after 2 hour dialysis. The bile acid retardation index after 30 minute dialysis was 3, 12 and $18{\%}$ in the presence of 1, 3 and $5{\%}$ ${\beta}-Glucan$, respectively. The effect was higher than the glucose retardation index and decreased as the dialysis time elapsed.

• Preventive Nutrition and Food Science
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• v.17 no.1
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• pp.8-13
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• 2012

This study was designed to investigate whether Sargassum ringgoldianum extract may inhibit ${\alpha}$-glucosidase and ${\alpha}$-amylase activities, and alleviate postprandial hyperglycemia in streptozotocin-induced diabetic mice. The $IC_{50}$ values of Sargassum ringgoldianum extract against ${\alpha}$-glucosidase and ${\alpha}$-amylase were 0.12 mg/mL and 0.18 mg/mL, respectively, which evidenced higher activities than those of acarbose. The blood glucose levels of the Sargassum ringgoldianum extract administered group were significantly lower compared to the control group in the streptozotocin-induced diabetic mice. Moreover, the area under the two-hour blood glucose response curve was significantly reduced and the absorption of dietary carbohydrates was delayed after administration of Sargassum ringgoldianum extract in the diabetic mice. Therefore, these results indicated that Sargassum ringgoldianum extract may help decrease the postprandial blood glucose level via inhibiting ${\alpha}$-glucosidase.

• Journal of Nutrition and Health
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• v.25 no.6
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• pp.429-449
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• 1992

The consumption of foods rich in TDF should not be associated with impaired mineral absorp-tion and long-term mineral status. In surveys of populations consuming high amounts of TDF e.g Third World populations and vegetarinas gross deficiencies in mineral nutrition have not been noted. If mineral status is low among these groups it is most likely caused by the inadequacy or imbalance of the diet and not by the TDF. The key word is interaction which should be inte-rpreted in dietary imbalances that produce nut-rient deficiencies. There are no strong data to support the concept that TDF inhibits mineral absorption through a binding chelation mechanism. Limited data sug-gest that positively charged groups on polymers such as chitosan and cholestyramine will decrease iron absorption in humans and animals. Because TDF does not contain positively charged groups future research should be directed at the possible role of protein consumed along with TDF and the combination of effects on mineral nutrition Phytic acid is acknowledged as a potent chela-tor of zinc. However its association with zinc and its propensity to lower Zn bioavaiability may enhance the absorption of other elements notably copper and iron. The importance of interactions among nutrients including TDF will gain addi-tional attention in the scientific community. Soluble and insoluble dietary fiber function di-fferently in the intestine. Insoluble fibers accele-rate movement through the intestine. Soluble die-tary fibers appear to regulated blood concentra-tions of glucose and cholesterol albeit by some unknown mechanism. In creased viscosity produ-ced by the SDF in the intestine may provide an explanation of how this class of polymers affects plasma glucose cholesterol and other nutrients. Employing a double-perfusion technique in the rat we demonstrated that viscosity produced by SDF will delay transfer of zinc into the circulatory system. This delayed absorption should not be interpreted as decreased utilization. A great deal of additional research is required to prove the importance of luminaly viscosity produced by SDF on slowing nutrient absorption or regulating bllod nutrient homeostasis. Increased intake of TDF in the total human diet appears desirable. A dietary intake of 35g/day should not be considered to have a negative effect on mineral absorption. It is important to educate people that an intake of more than 35g TDF/day may cause an imbalance in the diet that can adve-rsely affect mineral utilization. Acknowledgments. Appreciation is given to Dr. George V. Vahouny(deceased) who was intense a great competitor in and out of science and who gave the author inspiration Portions of this work were supported by the University of Missouri Ag-ricultural Station and by a grant from the Univer-rch Support Grant RR 07053 from the National Institutes of Health. Contribution of the Missouri Agriculatural Experiments Station Journal Series No. 10747.

• Nutritional Sciences
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• v.9 no.4
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• pp.295-300
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• 2006

Iron bound to heme appears to be more bioavailable than iron salts. A clinical study was performed to investigate the absorption efficiency of heme-iron and iron-salt products available. Heme-iron and nonheme-iron supplements have become available in Korea. We performed iron absorption studies to compare the absorption of heme-iron polypeptide (HIP) products made from digested hemoglobin, produced in Korea (HIPk) and imported from Japan (HIj), with that of iron salts. In the study, 80 subjects were divided into 5 groups (n=56): placebo group; 12 mg glucose, HIPk group; 12 mg iron as HIPk, HIj group; 12 mg iron as HIj, iron-salt group 1; 12 mg of iron as ferrous aminoacetate, and iron-salt group 2; 100 mg iron as ferrous aminoacetate. Changes in serum iron levels were measured at 3 and 5 hours post ingestion. Absorption of iron in HIPk was higher compared to HIj, iron-salt or placebo. There was a significant inverse correlation between low serum iron levels $(<80{\mu}g/dl)$ and iron absorption from HIPk. These results demonstrated that HIPk was more bioavailable, even taken with a meal, and would have potential advantages over iron salt or HIj as an iron supplement. Our results indicate that heme-iron absorption is regulated by iron status through a heme receptor, whereas iron-salt absorption is unregulated.

• Journal of Pharmaceutical Investigation
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• v.24 no.3
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• pp.11-18
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• 1994

We have studied the iron uptake by the purified brush-border membrane vesicles (BBMVs) to determine the effect of fructose on the absorption of iron. BBMVs were prepared by the modified calcium precipitation method, The degree of purification was routinely assessed by the marker enzyme, alkaline phosphatase, and the functional integrity was tested by $D-[1-^3H]glucose$ uptake. The appearance of membrane vesicles was shown by transmission electron microscopy (TEM). The uptakes of complexes of labeled iron $[^{59}Fe]$ with fructose and ascorbate were measured with a rapid filtration technique, The uptake rate and pattern of the two iron-complexes, Fe(III)-fructose and Fe(III)-ascorbate, were also observed. A typical overshooting uptake of D-glucose was observed with peak value of $2{\sim}3$ times higher concentration than that at equilibrium. This result was similar to other studies with BBMVs. TEM showed that the size of BBMVs was uniform and we can hardly find any contaminants, Fe(III)-fructose has the higher value of $V_{max}$ and the lower value of Km than those of Fe(III)-ascorbate, respectively. It may be concluded that D-fructose is more effective in promoting the iron absorption than ascorbate.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.88-89
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• 2000

Chitosan is derived from chitin by deacetylation in the presence of alkali, which is a copolymer consisting of $\beta$-(1longrightarrow4)-2-acetamido-D-glucose and $\beta$-(1longrightarrow4)-2-amino-D-glucose units with the latter usually exceeding 80% (Arvanitoyannis et al., 1998). Chitosan has been developed as new physiological material since it possesses antibacterial activity, hypocholesterolemic activity and antihypertensive action. However, even though chitosan has very strong functional properties in many areas, its high molecular weight and high viscosity may restrict the use in vivo. In addition, there is little doubt that such properties will influence absorption in the human intestine. Recently, studies on chitosan have attracted interest for converted chitosan to oligosaccharide, because the oligosaccharide possesses not only water-soluble property but also versatile functional properties such as antitumor activity, immune-enhancing effects, enhancement of protective effects against infection with some pathogens in mice, antifungal activity, calcium absorption accelerating effect (Jeon et al., 1999) and antimicrobial activity. There is, however, little information on the toxicity of chitosan oligosaccharide. (omitted)

• Journal of Yeungnam Medical Science
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• v.5 no.2
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• pp.79-86
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• 1988

In the present study the effect of exercise on the conversion rate of ingested glucose to glycogen in the different types of hindlimb skeletal muscles in Sprague-Dawley male rats was studied. The amounts of synthetized glycogen from ingested glucose of fast-twitch white(WV), fast-twitch red(RV), mixed type of fast-twitch white and red(EDL), and slow-twitch(SOL) muscles were determined at 30 and 90 min. after ingestion of 25% glucose solution which contained $^{14}C$-glucose($2m{\ell}(1uCi)$/100gm B. W.)in control and exercise loaded rats. The result was summarized as follows : The about 55% at 30 min. and 70% at 90 min. after glucose ingestion were absorbed from gastrointestinal tract. This result shows no effects of exercise on absorption rate from gastrointestinal tract. The amount of synthetized glycogen of SOL from ingested glucose at 30 and 90 min. after glucose ingestion were highest, whether WV were lowest in hindlimb skeletal muscles in control and exercise loaded rats. In the exercise loaded rats, the amounts of synthetized glycogen of SOL, RV, and EDL at 90 min. after glucose ingestion was much higher than control rats, but not different in WV between exercise-loaded and control rats. At 30 min. after glucose ingestion, only SOL of exercise loaded rats was higher than control rats. In the control rat, the synthesis of glycogen was almost completed during initial 30 minutes. On the other hand, in the exercise loaded rat, except WV was opposite result of control rats, i. e., amounts of synthetized glycogen were major during late period. The amount of synthetized glycogen of liver at 30 and 90 min. after glucose ingestion in exercise loaded rats was higher than control rats. The rate of glycogen synthesis in control and exercise loaded rats were higher between 30-90 minute than initial 30 minute.

• Korean Journal of Veterinary Research
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• v.63 no.3
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• pp.30.1-30.8
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• 2023

Metformin is a treatment used widely for non-insulin-dependent diabetes mellitus with few side effects and acts by inhibiting hepatic gluconeogenesis and glucose absorption from the gastrointestinal tract. Lymphoma is one of the most common hematological malignancies in dogs. Chemotherapy is used mainly on lymphoma, but further research on developing anticancer drugs for lymphoma is needed because of its severe side effects. This study examined the anticancer effects of metformin alone and in combination with 2-deoxy-D-glucose (2-DG), a glucose analog, on EL4 cells (mouse T cell lymphoma). Metformin reduced the metabolic activity of EL4 cells and showed an additive effect when combined with 2-DG. In addition, cell death was confirmed using a trypan blue exclusion test, Hochest 33342/propidium iodide (PI) staining, and Annexin V/PI staining. An analysis of the cell cycle and mitochondria membrane potential (MMP) to investigate the mechanism of action showed that metformin stopped the G2/M phase of EL4 cells, and metformin + 2-DG decreased MMP. Metformin exhibited anticancer effects as a G2/M phase arrest mechanism in EL4 cells and showed additive effects when combined with 2-DG via MMP reduction. Unlike cytotoxic chemotherapeutic anticancer drugs, metformin and 2-DG are related to cellular glucose metabolism and have little toxicity. Therefore, metformin and 2-DG can be an alternative to reduce the toxicity caused by chemotherapeutic anticancer drugs. Nevertheless, research is needed to verify the in vivo efficacy of metformin and 2-DG before they can be used in lymphoma treatments.

• YAKHAK HOEJI
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• v.51 no.6
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• pp.440-446
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• 2007

Arcabose is a competitive inhibitor of the intestinal ${\alpha}$-glucosidases and reduces the postprandial digestion and absorption of carbohydrate and disaccharides. Due to its negligible oral absorption, measuring drug concentration in the plasma is impractical. Thus, the common pharmacokinetic study is not available to determine the bioequivalence of the generic acarbose preparations. The aim of this study is the establishment of pharmacodynamic assessment method for the bioequivalence test of the generic acarbose preparations. Placebo-controlled cross-over ($3{\times}3$) clinical study was conducted in 23 healthy volunteers. Volunteers received a single oral dose of placebo, reference drug ($Glucoby^{(R)}$ 100 mg, Lot # D043) or test drug ($Glucoby^{(R)}$ 100 mg, Lot # E005) just before breakfast, then blood samples for evaluation of serum glucose and insulin levels were taken during for 4 hours. $C_{max},\;AUC_{0-2},\;AUC_{0-4},\;{\Delta}C_{max},\;{\Delta}AUC_{0-2}\;and\;{\Delta}AUC_{0-4}$ of the postprandial plasma glucose level significantly decreased when a single dose of acarbose 100 mg preparations was administered. However, any significant difference was not detected between the groups taken the reference drug and the test drug. These results proposed that the pharmacodynamic protocols of this study is suitable to use for bioequivalence test of acarbose preparations. On the basis of the results of this study and the data of literature on this subject, the standard protocols of bioequivalence study of acarbose preparation are proposed.