• Journal of Microbiology and Biotechnology
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• 제17권6호
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• pp.952-959
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• 2007

His-His-Leu (HHL), a tripeptide derived from a Korean soybean paste, is an angiotensin-I-converting enzyme (ACE) inhibitor. We report here a method of producing this tripeptide efficiently by expressing tandem multimers of the codons encoding the peptide in E. coli and purifying the HHL after hydrolysis of the peptide multimers. The HHL gene, tandemly multimerized to a 40-mer, was ligated with ubiquitin as a fusion gene (UH40). UH40 was inserted into vector pET29b; the UH40 fusion protein was then produced in E. coli BL21. The recombinant UH40 protein was purified by cation-exchange chromatography with a yield of 17.3mg/l and analyzed by matrixassisted laser desorption ionization (MALDI) time-of-flight (TOF) mass spectrometry and protein N-terminal sequencing. Leucine aminopeptidase was used to cleave a 405-Da HHL monomer from the UH40 fusion protein and the peptide was purified using reverse-phase high-performance liquid chromatography (HPLC) on a C18 HPLC column, with a final yield of 6.2mg/l. The resulting peptide was confirmed to be HHL with the aid of MALDI-TOF mass spectrometry, glutamine-TOF mass spectrometry, N-terminal sequencing, and measurement of ACE inhibiting activity. These results suggest that our production method is useful for obtaining a large quantity of recombinant HHL for functional antihypertensive peptide studies.

• Fisheries and Aquatic Sciences
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• 제14권3호
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• pp.174-178
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• 2011

This study aimed to determine the degree of hydrolysis and angiotensin-I-converting enzyme (ACE)-inhibitory activity of Giant Jellyfish Nemopilema nomurai (jellyfish) hydrolysates. The degree of hydrolysis using six proteolytic enzymes (Alcalase, Flavozyme, Neutrase, papain, Protamex, and trypsin) ranged from 13.1-36.8% and the inhibitory activities from 20.46-79.58%. Using papain hydrolysate, we newly isolated and characterized ACE-inhibitory peptides with a molecular weight of 3,000-5,000 Da that originated from jellyfish collagen. The purified peptide (FII-b) was predicted to be produced from an alpha-2 fragment of the type IV collagen of jellyfish. The N-terminal sequence of FII-b was Asp-Pro-Gly-Leu-Glu-Gly-Ala-His-Gly- and showed 87% identity to the collagen type IV alpha-2 fragment of Rattus norvegicus and a predicted protein from Nematostella vectensis, indicating that the ACE-inhibitory peptide originated from the collagen hydrolysate and had an $IC_{50}$ value of 3.8 ${\mu}g$/mL. The primary structure of the fragment is now being studied; this peptide represents an interesting new type of ACE inhibitor and will provide knowledge of the potential applications of jellyfish components as therapies for hypertension.

• Childhood Kidney Diseases
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• 제24권1호
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• pp.36-41
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• 2020

Purpose: Hepatitis B virus (HBV) infection is among etiologies of secondary membranous nephropathy (MN) in pediatric patients. We evaluated expression of phospholipase A2 receptor (PLA2R), a specific target antigen of primary MN, in pediatric HBV-related MN. Methods: We retrospectively reviewed patients with biopsy-proven HBV-related MN from the renal biopsy registry and electronic medical records of Severance Hospital, Seoul, Korea, from 1993 to 2004. Paraffin-embedded human kidney tissues were retrieved and immunohistochemically stained for PLA2R. Results: Ten pediatric patients with 13 biopsied specimens were reviewed. The predominant pathological stage was stage II-III, and second was stage II. The intensity of staining for IgG was greatest, with less intense staining for IgM, IgA, C3, C4, and C1q. All the patients had angiotensin-converting enzyme inhibitor combined with glucocorticoid, and four patients converted to cyclosporine treatment from glucocorticoid monotherapy. Urinalysis of all the patients normalized after variable period. PLA2R staining was demonstrated in the outer glomerulus in 3 out of 13 biopsies, 2 of which were obtained from the same patient over a 5-year interval. Conclusions: PLA2R was expressed in a small number of cases diagnosed as pediatric HBV-related MN, indicating that some HBV-related MN cases may be primary MN concurrent with HBV infection.

• 한국임상수의학회지
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• 제25권2호
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• pp.106-111
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• 2008

3년령 말티즈 개(2.5Kg)가 갑작스런 심잡음, 의기소침, 식욕결핍으로 내원하였다. 혈액검사상에서 백혈구증가증과 함께 발열이 관찰되었으며 심장청진시 좌측 심첨부에서 VI/VI holosystolic murmurs가 청진되었다. 심전도에서 좌심실의 종대소견이 보였다. 진단방사선상에서 좌심방과 좌심실의 확장, 이첨판 판막의 증식이 보였으며, 이로 인해 이첨판의 역류가 관찰되었다. 이러한 임상증상과 검사 결과를 바탕으로, 본 증례는 감염성 심내막염에 의한 증식성 이첨판 역류증이라 진단하였다. 환자는 광범위 항생제, 이뇨제, 항혈전제로 치료하였다.

• Journal of Yeungnam Medical Science
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• 제32권1호
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• pp.55-59
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• 2015

The widely used polyethylene glycol (PEG)-based solutions have been proven effective for bowel preparation when 4 L of the solution is administered before colonoscopy. However, large volumes of the solutions are generally poorly tolerated. A new PEG-based solution consisting of 2 L of PEG and a high dose of ascorbic acid has recently become available. Electrolyte abnormalities caused by PEG-based solutions have rarely been reported. We report on a case of acute severe hyponatremia with associated generalized tonic-clonic seizures after bowel preparation with a low-volume PEG plus ascorbic acid solution in a 74-year-old woman with no history of seizures. She took a beta blocker, an angiotensin-converting enzyme inhibitor, and glimepiride for hypertension and diabetes mellitus. She showed general weakness, nausea, agitation, muscle cramping, and seizures after ingestion of the PEG plus ascorbic acid solution. Her serum sodium level was 112 mEq/L. Her symptoms improved after intravenous administration of hypertonic saline. Physicians should pay attention to screening for electrolytes and development of neurological symptoms during bowel preparation.

• 한국균학회지
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• 제39권3호
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• pp.185-188
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• 2011

버섯으로부터 생리 기능성이 우수한 건강 소재나 대체의약을 개발하기 위하여 백색 느티만가닥버섯의 자실체의 물추출물과 에탄올추출물을 제조한 후 이들의 생리기능성을 측정하였다. 시료 버섯 자실체의 물 추출물의 ACE 저해활성이 60.5%로 에탄올 추출물의 저해활성 보다 높았다. 또한 SOD 유사활성과 Xanthine oxidase 저해 활성도 물추출물에서 각각 24.1%와 23.0%을 보였다. 백색 느티만가닥버섯 자실체에 함유되어있는 ACE 저해 물질은 자실체 분말을 물에 1 : 40으로 현탁 시킨 후 $50^{\circ}C$에서 12시간 추출했을 때 가장 많이 추출되었고 이때 ACE 저해활성은 80.5% 이었다.

• The Korean Journal of Physiology and Pharmacology
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• 제21권6호
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• pp.667-674
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• 2017

Angiotensin II (Ang II) is metabolized from N-terminal by aminopeptidases and from C-terminal by Ang converting enzyme (ACE) to generate several truncated angiotensin peptides (Angs). The truncated Angs have different biological effects but it remains unknown whether Ang-(4-8) is an active peptide. The present study was to investigate the effects of Ang-(4-8) on hemodynamics and atrial natriuretic peptide (ANP) secretion using isolated beating rat atria. Atrial stretch caused increases in atrial contractility by 60% and in ANP secretion by 70%. Ang-(4-8) (0.01, 0.1, and $1{\mu}M$) suppressed high stretch-induced ANP secretion in a dose-dependent manner. Ang-(4-8) ($0.1{\mu}M$)-induced suppression of ANP secretion was attenuated by the pretreatment with an antagonist of Ang type 1 receptor ($AT_1R$) but not by an antagonist of $AT_2R$ or $AT_4R$. Ang-(4-8)-induced suppression of ANP secretion was attenuated by the pretreatment with inhibitor of phospholipase (PLC), inositol triphosphate ($IP_3$) receptor, or nonspecific protein kinase C (PKC). The potency of Ang-(4-8) to inhibit ANP secretion was similar to Ang II. However, Ang-(4-8) $10{\mu}M$ caused an increased mean arterial pressure which was similar to that by 1 nM Ang II. Therefore, we suggest that Ang-(4-8) suppresses high stretch-induced ANP secretion through the $AT_1R$ and $PLC/IP_3/PKC$ pathway. Ang-(4-8) is a biologically active peptide which functions as an inhibition mechanism of ANP secretion and an increment of blood pressure.

• The Korean Journal of Physiology
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• 제19권2호
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• pp.173-187
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• 1985

Renal compensatory adaptation caused by ablation of a part of renal mass has long been known in the field of the compensatory renal hypertrophy or hyperplasia. Many reports were found on the chronic mechanisms on the compensatory renal hyperfunction after exclusion of the contralateral kidney. However the mechanism(s) of the acute compensatory hyperfunction after contralateral exclusion has not yet been clarified. In the present experiment, we have tried to prove the possibility of the involvement of the renin-angiotensin system and/or prostaglandin system in the control mechanism of the acute compensatory renal hyperfunction after contralateral kidney exclusion. There were found different responses of the renal hyperfunction by contralateral renal pedicle or ureteral occlusion. Contralateral renal pedicle or ureteral occlusion caused a sustained increases of the urinary volume, sodium and potassium excretion, while the magnitude of the changes was different quantitatively by the maneuvers. Blood collection affected on the acute compensatory renal responses after ureteral as well as renal pedicle occlusion. Plasma prostaglandin $E_2$ level was not changed by the contralateral renal pedicle or ureteral occlusion. Urinary excretion of Prostaglandin $E_2$, the indices of renal prostaglandin biosynthesis, was not changed by the contralateral renal pedicle occlusion, but increased without significance by the contralateral ureteral occlusion. Acute renal compensatory responses after contralateral renal pedicle occlusion were blocked by the pretreatment of indomethacin. Plasma renin activity increased after contralateral ureteral occlusion, but the pattern of the increases was the same as in the time-control group. Plasma renin activity after contralateral renal pedicle occlusion did not change by the time sequence. SQ 20,881, an angiotensin I converting enzyme inhibitor, blunted the contralateral renal responses after the renal pedicle occlusion. Bilateral renal denervation abolished the contralateral renal responses after the renal pedicle occlusion. The above data suggest that there is no direct evidence to support the involvement of the renin-angiotensin system and/or prostaglandin system for the acute compensatory renal hyperfunction after contralateral kidney exclusion, and that the functional changes of the intact kidney may be caused by a humoral substances, or other mechanisms by afferent renal nerve activity originating from the treated kidney.

• The Korean Journal of Physiology
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• 제19권2호
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• pp.189-202
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• 1985

Enhanced activity of renin-angiotensin-aldosterone system has been suggested as a cause of the high blood pressure in certain forms of experimental hypertension. In spontaneously hypertensive rats, however, increased activity of the system has not been found, and even suppressed renin angiotensin system has been reported in the spontaneously hypertensive rat. In the present experiments it was attempted to explore the possible alteration of the short loop negative feedback control in the hypertensive rat. Experiments have been done in the anesthetized spontaneously hypertensive rats(SHR) as well as in normotensive Wistar and Sprague Dawley rats as control. Responses of the plasma renin activity to the intravenous L-isoproterenol were dose dependent, in both SHR and normotensive control rats. Hypotensive responses to smaller do sea of L-isoproterenol were more accentuated in SHR than in the normotensive control rats. Angiotensin If given intravenously suppressed plasma renin activity in a dose dependent fashion in both groups. However, these suppressive responses were significantly attenuated in SHR as compared with the normotensive control rats. Treatment with angiotensin I-converting enzyme inhibitor did not correct the attenuated responses of the plasma renin activity to angiotensin II in SHR. Intravenous infusion of arginine vasopressin also produced a dose-dependent suppression of plasma renin activity in both groups. The responses to arginine vasopressin were also significantly attenuated to the normotensive control rats. In the sodium-depleted SHR, arginine vasopressin did not suppress plasma renin activity, whereas the suppressive responses to arginine vasopressin in the normotensive control rats were not different from the untreated control rats. These data suggest that there may be a derangement in the short loop negative feedback control of the renin-angiotensin system in spontaneously hypertensive rat.

• Archives of Pharmacal Research
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• 제19권5호
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• pp.390-395
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• 1996

To investigate whether $AT_{1}$ receptor antagonists are acting by increasing endothelium-de-pendent and -independent relaxation of aortas in normotensive rats, $AT_{1}$ receptor antagonists, losartan and KR-30988, and angiotensin converting enzyme inhibitor, captopril, were orally administered for two weeks (50 mg/kg, b.i.d.). THe blood pressure, heart rate and body weight were not significantly changed by losartan, KR-30988 and captopril compared to the control group. In aortic preparations, the $pD_{2}$ of KR-30988 for ACh-induced relaxation was 8.33 $\pm$ 0.16, significantly (p <0.05) lower than that of control group $(7.71 \pm 0.15)$. ACh-induced relaxation was significantly increased on losartan-treated group (p<0.01) at $10^{-6}$ M of ACh, and in captopril-treated group (p<0.05) at the range of $10^{-7}$ -$10^{-5}$ M of ACh. The $pD_{2}$ values for histamine-induced relaxatio of losartan, KR-30988 and captopril were 5.57 $\pm$ 0.10, 5.85 $\pm$ 0.21 and 5.60 $\pm$ 0.01, respectively, with significant differences in all groups (p<0.01) compared to that of control group (5.13 $\pm$ 0.09). ACh-induced relaxations of aortic preparations were not changed by pretreatment of indomethacin ($10_{-5}$ M), and completely bolcked by pretreatment of L-NAME $(10_{-5}M)$ in all groups. Sodium nitroprusside-induced relaxations were not significantly changed by all drugs tested in this experiments. These results suggest that $AT_{1}$ receptor antagonists, losartan and KR-30988, enhance the endothelium-dependent relaxatio on aortic preparations through the release of, or increase sensitivity, to nitric oxide in nor-motensive rats.