• Korean Journal of Clinical Pharmacy
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• v.15 no.1
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• pp.55-60
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• 2005

The aim of this study is to investigate the effect of naringin on the pharmacokinetics of tamoxifen in rats. Tamoxifen (10 mg/kg) was administered orally 0.5 h and 3 days after oral administration of naringin (5 mg/kg). The plasma concentrations of tamoxifen were increased significantly tv naringin compared to control. Absorption rate constant ($K_a$) of tamoxifen with naringin was increased significantly compared to that of the control. The areas under the plasma concentration-time curve (AUC) and the peak concentrations ($C_{max}$) of tamoxifen with naringin were significantly higher than those of the control. Consequently, the relative bioavailability (R.B${\%}$) of tamoxifen with naringin was 2-3-fold higher than the control, and absolute bioavailability (A.B${\%}$) of tamoxifen were significantly higher (p<0.05 with coadministration, p<0.01 with pretreatment) than those of the control. The increased bioavailability of tamoxifen in rats with naringin might be associated with the inhibition by naringin of an efflux pump P-glycoprotein and the first-pass metabolizing enzyme CYP3A4.

• Journal of Marine Bioscience and Biotechnology
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• v.12 no.1
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• pp.50-58
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• 2020

Sphacelaria is a filamentous brown algal genus that can be epibiotic on macroalgae, marine plants, and sea turtles. Its important role in benthic ecosystems, exposure to different stressors (e.g., grazing), and use as a model organism make Sphacelaria ideal for assessing physiological responses of organisms to environmental inputs. Single-cell RNA sequencing is a powerful new probe for understanding environmental responses of organisms at the molecular (transcriptome) level, capable of delineating gene regulation in different cell types. In the case of plants, this technique requires protoplasts ("naked" plant cells). The existing protoplast isolation protocols for Sphacelaria use non-commercial enzymes and are low-yielding. This study is the first to report the production of protoplasts from Sphacelaria fusca (Hudson) S.F. Gray, using a combination of commercial enzymes, chelation, and osmolarity treatment. A simple combination of commercial enzymes (cellulase Onozuka RS, alginate lyase, and driselase) with chelation pretreatment and an increased osmolarity (2512 mOsm/L H₂O) gave a protoplast yield of 15.08 ± 5.31 × 10⁴ protoplasts/g fresh weight, with all the Sphacelaria cell types represented. Driselase had no crucial effect on the protoplast isolation. However, the increased osmolarity had a highly significant and positive effect on the protoplast isolation, and chelation pretreatment was essential for optimal protoplast yield. The protocol represents a significant step forward for studies on Sphacelaria by efficiently generating protoplasts suitable for cellular studies, including single-cell RNA sequencing and expression profiling.

• Herbal Formula Science
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• v.6 no.1
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• pp.187-197
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• 1998

The study was aimed to investigate the effect cuscutae semen(CS) on the vascular systems including changes in blood pressure (BP), regional cerebral blood flow(rCBF) and pial arteriolar diameter of male Sprague-Dawely rats. The changes in rCBF were determinated by laser-Doppler flowmetry, and the changes in diameter of pial arteriole were measured through a closed crainal window. 1. Blood pressure was not affected by CS in rats. 2. rCBF was increased by CS in a dose-dependent manner. 3. Pretreatment with methylene blue(Img/kg), and propranolol(1mg/kg) significantly inhibited CS induced increased in rCBF. 4. Pretreatment with indomethacin(1mg/kg) did not inhibited CS induced increased in rCBF. 5. Pial arterial diameter was increased by CS in a dose-dependent manner. These results suggest that CS causes a diverse response of blood pressure, regional cerebral blood flow(rCBF), and pial arteral diameter. The increased in rCBF is also mediated by adrenergic ${\beta}-receptor $ and guanylate cyclase.

• Biomolecules & Therapeutics
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• v.12 no.2
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• pp.68-73
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• 2004

This study was performed to investigate the regulatory mechanism of cerebral blood How of adenosine $A_2$ receptor agonist in the rats, and to define whether its mechanism is mediated by nitric oxide (NO), adenylate cyclase and guanylate cyclase. In pentobarbital-anesthetized, pancuronium-paralyzed and artificially ventilated male Sprague-Dawley rats, all drugs were applied topically to the cerebral cortex. Blood flow from cerebal cortex was measured using laser-Doppler flowmetry. Topical application of an adenosine $A_2$ receptor agonist [5'-(N-cyclopropyl)-carboxamidoadenosine (CPCA; 4 umol/l)] increased cerebral blood flow. This effect of CPCA (4 umol/l) was blocked by pretreatment with NO synthase inhibitor [$N^G$-nitro-L-argine methylester (L-NAME; 140 umol/l)] and adenylate cyclase inhibitor [MDL-12,330 (20 umol/l)]. But the effect of CPCA (4 umol/l) was not blocked by pretreatment with guanylate cyclase inhibitor [LY-83,583 (10 umol/l)]. These results suggest that adenosine $A_2$ receptor increases cerebral blood How. It seems that this action of adenosine $A_2$ receptor is mediated via the NO and the activation of adenylate cyclase in the cerebral cortex of the rats.

• Biomolecules & Therapeutics
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• v.12 no.2
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• pp.108-113
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• 2004

This study was performed to investigate the regulatory mechanism of cerebral blood flow of adenosine $A_{2B}$ receptor agonist in the rats, and to define whether its mechanism is mediated by adenylate cyclase and guanylate cyclase. in pentobarbital-anesthetized, pentobrabital-paralyzed and artificially ventilated male Sprague-Dawley rats, all drugs were applied topically to the cerebral cortex. Blood How from cerebral cortex was measured using laser-Doppler flowmetry. Topical application of an adenosine $A_{2B}$ receptor agonist, 5'-N-ethylcar-boxamidoadenosine (NECA; 4 umol/l) increased cerebral blood flow. This effect of NECA (4 umol/l) was not blocked by pretreatment with adenylate cyclase inhibitor, MDL-12330 (20 umol/l). But effect of NECA (4 umol/l) was blocked by pretreatment with guanylate cyclase inhibitor, LY-83383 (10 umol/l). These results suggest that adenosine $A_{2B}$ receptor increases cerebral blood flow. It seems that this action of adenosine $A_{2B}$ receptor is mediated via the activation of guanylate cyclase in the cerebral cortex of the rats.

• Herbal Formula Science
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• v.15 no.2
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• pp.89-98
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• 2007

Kyungisan (KGS) has been used in oriental medicine for many centuries as a therapeutic agent for treatment of stroke caused by deficiency of qi(氣虛). This study was performed to evaluate effects of KGS extract on the regional cerebral blood flow(rCBF) and mean arterial blood pressure(MABP) in rats. The result of this study were as follow ; 1. KGS significantly increased rCBF irrelevant to MABP in normal rats, 2. To prescribe KGS after pretreatment with indomethacin(IDN) decreased rCBF as compared with control group to administered only KGS in normal rats. But the change of MABP is not significantly as compared with control group. 3. To prescribe KGS after pretreatment with methylen blue( MTB) decreased MABP and rCBF as compared with control group to administered only KGS in normal rats. Especially, it significantly decreased rCBF. These results suggest that KGS increase rCBF by enlargement diameter of pial artery in brain. The active mechanism of KGS is related with prostaglandin activated by cyclooxygenase. So, I suggest that KGS has an anti-ischemic effect through the improvement of cerebral blood flow and can be used for stroke.

• Preventive Nutrition and Food Science
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• v.20 no.1
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• pp.52-59
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• 2015

This study was to investigate the preventive effect of taemyeongcheong (TMC, a Korean traditional health drink) on acetaminophen (APAP, 800 mg/kg BW)-induced hepatic damage in ICR mice. TMC is prepared from Saururus chinensis, Taraxacum officinale, Zingiber officinale, Cirsium setidens, Salicornia herbacea, and Glycyrrhizae. A high dose of TMC (500 mg/kg BW) was found to decrease APAP-induced increases in serum levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase. TMC pretreatment also increased the hepatic levels of hepatic catalase, superoxide dismutase, glutathione peroxidase, and glutathione, and reduced serum levels of the inflammatory cytokines tumor necrosis factor (TNF)-${\alpha}$ and interleukin (IL)-6 in mice administered APAP (P<0.05). TMC (500 mg/kg BW) reduced hepatic mRNA levels of TNF-${\alpha}$, IL-$1{\beta}$, IL-6, COX-2, and iNOS by 87%, 84%, 89%, 85%, and 88%, respectively, in mice treated with APAP (P<0.05). Furthermore, histological observations suggested TMC pretreatment dose-dependently prevented APAP-induced hepatocyte damage. These results suggest that TMC could be used as a functional health drink to prevent hepatic damage.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.5
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• pp.567-575
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• 2018

Acute kidney injury (AKI), which is defined as a rapid decline of renal function, becomes common and recently recognized to be closely intertwined with chronic kidney diseases. Current treatment for AKI is largely supportive, and endoplasmic reticulum (ER) stress has emerged as a novel mediator of AKI. Since carbon monoxide attenuates ER stress, the objective of the present study aimed to determine the protective effect of carbon monoxide releasing molecule-2 (CORM2) on AKI associated with ER stress. Kidney injury was induced after LPS (15 mg/kg) treatment at 12 to 24 h in C57BL/6J mice. Pretreatment of CORM2 (30 mg/kg) effectively prevented LPS-induced oxidative stress and inflammation during AKI in mice. CORM2 treatment also effectively inhibited LPS-induced ER stress in AKI mice. In order to confirm effect of CO on the pathophysiological role of tubular epithelial cells in AKI, we used mProx24 cells. Pretreatment of CORM2 attenuated LPS-induced ER stress, oxidative stress, and inflammation in mProx24 cells. These data suggest that CO therapy may prevent ER stress-mediated AKI.

• Biomolecules & Therapeutics
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• v.3 no.3
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• pp.199-204
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• 1995

Gastrodia elata is a medicinal plant which has been used as anticonvulsant in Korea, Japan and China. This study was conducted to examine the action mechanism of Gastrodia elata centering around the change of GABA and glutamic acid level in brain while observing the anticonvulsive effect in PTZ-induced seizure model. Seizures were reduced effectively by pretreatment of ether soluble part of methanol extract of Gastrodia elata. The pretreatment of ether soluble part inhibited not only the decrease of brain GABA level but also the increase of brain glutamic acid level observed in PTZ model of convulsive dose. Although there was not any change in glutamic acid level, the same development was also observed in the model of subconvulsive dose. From above results, it seems that the anticonvulsive component of Gastrodia elata is lipophilic, and its action mechanism is originated from both control action of GABA level and inhibition of glutaminergic neurotransmission.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.3
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• pp.797-801
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• 2005

While conducting an in vitro screening of various medicinal plant extracts, an aqueous extract of Rosa rugosa Radix (ARR) was found to exhibit a distinct vasorelaxant activity. ARR induced a concentration-dependent relaxation of the phenylephrine-precontracted aorta. This effect disappeared with the removal of functional endothelium. Pretreatment of the aortic tissues with NG-nitro-L-arginine methyl ester (L-NAME) or 1H-[1,2,4]-oxadiazole-[4,3-]-quinoxalin-1-one (ODQ) completely inhibited the relaxation induced by ARR. ARR-induced vascular relaxations were also markedly attenuated by addition of diltiazem or verapamil. However, the relaxant effect of ARR was not blocked by pretreatment with indomethacine, tetraethylammonium (TEA), glibenclamide, atropine, or propranolol. Taken together, the present study suggests that ARR dilates vascular smooth muscle via endothelium-dependent NO/cGMP signaling.