• Journal of Acupuncture Research
• /
• 제18권3호
• /
• pp.123-133
• /
• 2001

Objective : This study was undertaken to determine whether Cordyceps sinensis Sacc. (CSS) extract exerts the protective effect against oxidant-induced alterations in membrane transport function in renal tubules. Methods : Membrane transport fucntion was estimated by examining alterations in p-aminohippurate (PAH) uptake in rabbit renal cortical slices. For induction oxidative stress, slices were treated with an organic peroxide cumene hydroperoxide for 60 min at $37^{\circ}C$. Cumene hydroperoxide inhibited PAH uptake in a time dependent manner. Results : CSS at 0.5-5% concentrations prevented cumene hydroperoxide-induced inhibition of PAH uptake. CSS at 1% also attenuated LDH release and lipid peroxidation induced by cumene hydroperoxide. When slices were treated with 0.2 mM mercury chloride, PAH uptake was inhibited and lipid peroxidation was increased. These changes by mercury were significantly prevented by CSS. Conclusion : These results suggest that CSS prevents oxidant-induced alterations in membrane transport function in rabbit renal cortical slices. Such protective effect of CSS may be attributed to inhibition of peroxidation of membrane lipid.

• Nutrition Research and Practice
• /
• 제15권5호
• /
• pp.568-578
• /
• 2021

BACKGROUND/OBJECTIVES: Psidium guajava L. (guava) leaves have been shown to exhibit hypoglycemic and antidiabetic effects in rodents. This study investigated the effects of guava leaf extract on adipogenesis, glucose uptake, and lipolysis of adipocytes to examine whether the antidiabetic properties are mediated through direct effects on adipocytes. MATERIALS/METHODS: 3T3-L1 cells were treated with 25, 50, 100 ㎍/mL of methanol extract from guava leaf extract (GLE) or 0.1% dimethyl sulfoxide as a control. Lipid accumulation was evaluated with Oil Red O Staining and AdipoRed assay. Immunoblotting was performed to measure the expression of adipogenic transcription factors, fatty acid synthase (FAS), and AMP-activated protein kinase (AMPK). Glucose uptake under basal or insulin-stimulated condition was measured using a glucose analog 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) amino]-2-deoxy-D-glucose. Lipolysis from fully differentiated adipocytes was measured by free fatty acids release into the culture medium in the presence or absence of epinephrine. RESULTS: Oil Red O staining and AdipoRed assay have shown that GLE treatment reduced lipid accumulation during adipocyte differentiation. Mitotic clonal expansion, an early essential event for adipocyte differentiation, was inhibited by GLE treatment. GLE inhibited the expression of transcription factors involved in adipocyte differentiation, such as peroxisome proliferator-activated receptor 𝛄 (PPAR𝛄), CCAAT/enhancer-binding protein α (C/EBPα), and sterol regulatory element-binding protein-1c (SREBP-1c). FAS expression was also decreased while the phosphorylation of AMPK was increased by GLE treatment. In addition, GLE increased insulin-induced glucose uptake into adipocytes. In lipid-filled mature adipocytes, GLE enhanced epinephrine-induced lipolysis but reduced basal lipolysis dose-dependently. CONCLUSIONS: The results show that GLE inhibits adipogenesis and improves adipocyte function by reducing basal lipolysis and increasing insulin-stimulated glucose uptake in adipocytes, which can be partly associated with antidiabetic effects of guava leaves.

• 대한한의학회지
• /
• 제20권3호
• /
• pp.77-86
• /
• 1999

This study was undertaken to evaluate the effect of Sunghyangchungi-san (SHCS) on the oxidant-induced contraction and lipid peroxidation in rabbit carotid artery. Vascular rings isolated from rabbit carotid artery were exposed to t-butyl hydroperoxide (t-BHP), an extrinsic oxidant, and the effect of SHCS on the changes of vascular tension and lipid peroxidation induced by t-BHP was determined. t- BHP induced a slowly developing and sustained contraction of the arterial rings. SHCS effectively relaxed the arterial rings that were pre-contracted by t-BHP. The responses to SHCS were partially dose-dependent at concentrations lower than 0.5 mg/ml. When SHCS was applied prior to the exposure to t-BHP, it inhibited the t-BHP-induced contraction as well. t- BHP increased lipid peroxidation in a dose-dependent manner. SHCS as well as well-known anti-oxidants GSH and DPPD reduced significantly lipid peroxidation induced by t-BHP. SHCS partially blocked the increase in $^{45}Ca$ uptake induced by t-BHP. In contrast to SHCS, anti-oxidants GSH and DPPD failed to inhibit significantly the t- BHP-induced contraction or $^{45}Ca$ uptake. From the above results, it is suggested that SHCS relaxed t-BHP-induced contraction of rabbit carotid artery independently of its anti-oxidant action, and inhibition of $Ca^{2+}$ influx may contribute to the underlying mechanism.

• Journal of Acupuncture Research
• /
• 제18권4호
• /
• pp.143-151
• /
• 2001

Objective : This study was undertaken to determine whether Scutellaria balicalensis Georgi (SbG) extract exerts the protective effect against oxidant-induced alterations in organic cation transport in the renal proximal tubule. Methods : Organic cation transport was estimated by examining alterations in tetraethylammon - ium(TEA) uptake in rabbit renal cortical slices. The slices were treated with 0.2 mM tBHP for 60 min at $37^{\circ}C$. tBHP caused an inhibition in TEA uptake by renal cortical slices. Such an effect was accompanied by depressed Na+-K+-ATPase activity and ATP depletion. tBHP also induced a significant increase in LDH release. Results : SbG prevented tBHP-induced inhibition of TEA uptake in a dose-dependent manner at the concentration ranges of 0.05-0.1%. tBHP-induced inhibition of Na+-K+-ATPase activity and ATP depletion were significantly prevented by 0.05% SbG. tBHP-induced LDH release also was blocked by SbG. tBHP caused a significant increase in lipid peroxidation and its effect was prevented by SbG. Conclusion : These results suggest that SbG prevents oxidant-induced alterations in organic cation transport in rabbit renal cortical slices. Such protective effects of SbG may be attributed to inhibition of peroxidation of membrane lipid.

• Asian-Australasian Journal of Animal Sciences
• /
• 제30권1호
• /
• pp.111-118
• /
• 2017

Objective: Adipose tissue plays a key role in the development of obesity and diabetes. We previously reported that lignosulfonic acid suppresses the rise in blood glucose levels through the inhibition of ${\alpha}$-glucosidase activity and intestinal glucose absorption. The purpose of this study is to examine further biological activities of lignosulfonic acid. Methods: In this study, we examined the effect of lignosulfonic acid on differentiation of 3T3-L1 cells. Results: While lignosulfonic acid inhibited proliferation (mitotic clonal expansion) after induction of differentiation, lignosulfonic acid significantly increased the size of accumulated lipid droplets in the cells. Semi-quantitative reverse transcription polymerase chain reaction analysis showed that lignosulfonic acid increased the expression of the adipogenic transcription factor, peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$), leading to increased glucose transporter 4 (Glut-4) expression and 2-deoxyglucose uptake in differentiated 3T3-L1 cells. Additionally, feeding lignosulfonic acid to diabetic KK-Ay mice suppressed increase of blood glucose level. Conclusion: Lignosulfonic acid may be useful as a functional anti-diabetic component of food.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
• /
• 제10권S_4호
• /
• pp.189-196
• /
• 2001

The blue green alga, Microcystis aeruginosa, was found to accumulate proline under the stressful concentration of cupric ions. The changes of proline level in Microcystis aeruginosa in response to copper(Cu) have been monitored and the function of the accumulated proline was studied with respect to its effect on Cu uptake. Exposure of Microcystis aeruginosa elevated concentrations of Cu led to accumulation of fee proline depending on the concentrations of the metal in the external medium. The greater the toxicity or accumulation of the metal, the higher the amount of proline in algal cells were found. When proline was exogenously supplied prior to Cu treatment, the absorption of Cu was markedly reduced. When exogenous proline was supplied after Cu treatment, it resulted in a remarkable desorption of the adsorbed Cu immediately after the addition of proline. Pretreatment of Microcystis aeruginosa with proline counteracted with metal-induced lipid peroxidation. The results of the present study showed a protective elect of proline on metal toxicity through inhibition of lipid peroxidation and suggested that the accumulation of proline may be related to the tolerance mechanism for dealing with Cu stress.

• 대한한방내과학회지
• /
• 제18권1호
• /
• pp.147-155
• /
• 1997

This study was undertaken to determine whether Salviae-radix (SVR) exraction exerts benefical effect against oxidant-induced inhibition of tetraethylammonium (TEA) uptake which is actively secreted by renal proximal tubules. TEA uptake increased as function of incubation time to 60 min. When renal cortical slices were exposed to 50 mM $H_2O_2$, TEA uptake was significantly inhibited. The inhibition was significantly protected by addition of 0.5% SVR extraction. The benefical effect of SVR was dose-dependent over the concentration range of 0.1-1%; $H_2O_2$ (50 mM)-induced inhibition of TEA uptake was completely protected by 0.5-1% SVR extraction. $H_2O_2$ increased LDH release which was accompanied by an increase in lipid peroxidation in renal cortical slices. These changes were prevented by 0.5% SVR. These results suggest that SVR exerts benefical effect against oxidant-induced impairment of membrane transport function, this effect may be due to by an antioxidant action.

• The Korean Journal of Physiology and Pharmacology
• /
• 제3권5호
• /
• pp.529-538
• /
• 1999

This study was undertaken to examine the effect of ethanol on $Na^+ -dependent$ phosphate $(Na^+-P_i)$ uptake in opossum kidney (OK) cells, an established renal proximal tubular cell line. Ethanol inhibited ^Na^+-dependent$ component of phosphate uptake in a dose-dependent manner with $I_{50}$ of 8.4%, but it did not affect $Na^+-independent$ component. Similarly, ethanol inhibited $Na^+-dependent$ uptakes of glucose and amino acids (AIB, glycine, alanine, and leucine). Microsomal $Na^+-K^+-ATPase$ activity was not significantly altered when cells were treated with 8% ethanol. Kinetic analysis showed that ethanol increased $K_m$ without a change in $V_{max}$ of $Na^+-P_i$ uptake. Inhibitory effect of n-alcohols on $Na^+-P_i$ uptake was dependent on the length of the hydrocarbon chain, and it resulted from the binding of one molecule of alcohol, as indicated by the Hill coefficient (n) of 0.8-1.04. Catalase significantly prevented the inhibition, but superoxide dismutase and hydroxyl radical scavengers did not alter the ethanol effect. A potent antioxidant DPPD and iron chelators did not prevent the inhibition. Pyrazole, an inhibitor of alcohol dehydrogenase, did not attenuate ethanol-induced inhibition of $Na^+-P_i$ uptake, but it prevented ethanol-induced cell death. These results suggest that ethanol may inhibit $Na^+-P_i$ uptake through a direct action on the carrier protein, although the transport system is affected by alterations in the lipid environment of the membrane.

• 대한임상검사과학회지
• /
• 제41권2호
• /
• pp.83-92
• /
• 2009

This study was undertaken to examine the effect of oxidants on membrane transport function in renal epithelial cells. Hydrogen peroxide ($H_2O_2$) was used as a model oxidant and the membrane transport function was evaluated by measuring $Na^+$-dependent phosphate ($Na^+$-Pi) uptake in opossum kidney (OK) cells. $H_2O_2$ inhibited $Na^+$-Pi uptake in a dose-dependent manner. The oxidant also caused loss of cell viability in a dose-dependent fashion. However, the extent of inhibition of the uptake was larger than that in cell viability. $H_2O_2$ inhibited $Na^+$-dependent uptake without any effect on $Na^+$-independent uptake. $H_2O_2$-induced inhibition of $Na^+$-Pi uptake was prevented completely by catalase, dimethylthiourea, and deferoxamine, suggesting involvement of hydroxyl radical generated by an iron-dependent mechanism. In contrast, antioxidants Trolox, N,N'-diphenyl-p-phenylenediamine, and butylated hydroxyanisole did not affect the $H_2O_2$ inhibition. Kinetic analysis indicated that $H_2O_2$ decreased Vmax of $Na^+$-Pi uptake with no change in the Km value. Phosphonoformic acid binding assay did not show any difference between control and $H_2O_2$-treated cells. $H_2O_2$ also did not cause degradation of $Na^+$-Pi transporter protein. Reduction in $Na^+$-Pi uptake by $H_2O_2$ was associated with ATP depletion and direct inhibition of $Na^+$-$K^+$-ATPase activity. These results indicate that the effect of $H_2O_2$ on membrane transport function in OK cells is associated with reduction in functional $Na^+$-pump activity. In addition, the inhibitory effect of $H_2O_2$ was not associated with lipid peroxidation.

• 대한한방소아과학회지
• /
• 제22권2호
• /
• pp.141-153
• /
• 2008

Objectives : This study was designed to investigate the effects of Nelumbinis Rhizomatis Nodus(NRN) on production levels of Blood Glucose and Serum Lipid Levels. Methods : This study is about changes of blood glucose levels, body weights, levels of food and water uptake, levels of total cholesterol in the body, triglyceride, Creatinine, and BUN production by NRN extract. Results : Treatment with NRN regulated blood glucose levels effectively, but treatment with NRN did not affect body weights, food and water uptake. In addition, treating with NRN also lowered levels of total cholesterol, which is important for diabetes, and also lowered levels of triglyceride, too. Serum Creatinine levels were not affected, but serum BUN levels were lowered by treating with NRN, which were elevated in diabetes. Conclusions : These results demonstrate that NRN is effective to treat DM level and also has anti-hyperlipidemic effect.