Modification of Substrate Inhibition of Synaptosomal Acetylcholinesterase by Cardiotoxins

Ranaei-Siadat, Seyed-Omid,Riazi, Gholam-Hosein,Sadeghi, Mehdi,Chang, Long-Sen,Lin, Shinne-Ren,Eghtesadi-Araghi, Peyman,Hakimelahi, Gholam Hossein,Moosavi-Movahedi, Ali Akbar Korean Society for Biochemistry and Molecular Biol 2004 Journal of biochemistry and molecular biology Vol.37 No.3

Different types of cardiotoxin (I-V and n) were isolated and purified from the venom of the Taiwan cobra (Naja naja atra). The effects of these cardiotoxins were studied on membrane-bound acetylcholinesterase, which was isolated from a sheep's brain cortex. The results showed that cardiotoxins I-III, V, and n activated the enzyme by modification of substrate inhibition, but cardiotoxin IV's reaction was different. The inhibition and activation of acetylcholinesterase were linked to the functions of the hydrophobicity index, presence of a cationic cluster, and the accessible arginine residue. Our results indicate that Cardiotoxins have neither a cationic cluster nor an arginine residue in their surface area of loop I; therefore, in contrast to fasciculin, cardiotoxins are attached by loop II to the peripheral site of the enzyme. As a result, fasciculin seems to stabilize nonfunctional conformation, but cardiotoxins seem to stabilize the functional conformation of the enzyme. Based on our experimental and theoretical findings, similar secondary and tertiary structures of cardiotoxins and fasciculin seem to have an opposite function once they interact with acetylcholinesterase.

Modification of Substrate Inhibition of Synaptosomal Acetylcholinesterase by Cardiotoxins

( Seyed Omid Ranaei Siadat ),( Gholam Hosein Riazi ),( Mehdi Sadeghi ),( Long Sen Chang ),( Shinne Ren Lin ),( Peyman Eghtesadi Araghi ),( Gholam Hossein Hakimelahi ),( Ali Akbar Moosavi Movahedi ) 생화학분자생물학회 2004 BMB Reports Vol.37 No.3

Different types of cardiotoxin (I-V and n) were isolated and purified from the venom of the Taiwan cobra (Naja naja atra). The effects of these cardiotoxins were studied on membrane-bound acetylcholinesterase, which was isolated from a sheep`s brain cortex. The results showed that cardiotoxins I-III, V, and n activated the enzyme by modification of substrate inhibition, but cardiotoxin IV`s reaction was different. The inhibition and activation of acetylcholinesterase were linked to the functions of the hydrophobicity index, presence of a cationic cluster, and the accessible arginine residue. Our results indicate that Cardiotoxins have neither a cationic cluster nor an argininge residue in their surface area of loop I; therefore, in contrast to fasciculin, cardiotoxins are attached by loop II to the peripheral site of the enzyme. As a result, fasciculin seems to stabilize nonfunctional conformation, but cardiotoxins seem to stabilize the functional conformation of the enzyme. Based on our experimental and theoretical findings, similar secondary and tertiary structures of cardiotoxins and fasciculin seem to have an opposite function once they interact with acetylcholinesterase. s

차가버섯 용매추출분획의 Acetylcholinesterase 저해활성에 대한 동역학 및 열역학적 해석

김학규,허원,홍억기,이신영 한국산업식품공학회 2011 산업 식품공학 Vol.15 No.4

Twenty four fractions by solvent extraction and/or acid precipitation from fruit body and culture broth of Inonotus obliquus were prepared, and their inhibitory effect against acetylcholinesterase (AChE) was investigated. Among these fractions, acid (1 M HCl) precipitates from cell-free culture broth and fruit body exhibited the highest inhibitory effect on AChE in vitro. Acid precipitates inhibited AChE activity in a concentration-dependant manner and IC50 values of both acid precipitates were 0.53 mg/mL. The inhibition pattern was general non-competitive inhibition. The energetic parameters were also determined by dual substrate/temperature design. Both acid precipitates increased the values of Ea, ΔH, ΔG and ΔH* decreasing the value of ΔS for AChE. The results implied that the acid precipitates from I. obliquus increased the thermodynamic barrier, leading to the breakdown of ES complex and the formation of products as inhibitory mechanism.

Articles : Signal Analysis of Fiber-Optic Biosensor for the Detection of Organophosphorus Compounds in the Contaminated Water

( Jeong Woo Choi ),( Jun Hong Min ),( Won Hong Lee ) 한국화학공학회 1997 Korean Journal of Chemical Engineering Vol.14 No.2

The fiber-optic biosensor consisted of tubular enzyme reactor and two sensing parts was developed for the detection of organophosphorus compounds in a contaminated water. The organophosphorus compounds was measured by acetylcholinesterase entrapped by Ca-alginate gel on a silicon tube. The litmus dye was used as the indicator of color change due to the inhibition of organophosphorus compounds on the acetylcholinesterase. Transmittance change of light at the input and output parts of tubular enzyme reactor was detected. The biosensor has the linear analytical range of 0-1.0 ppm with response time of 5 minutes. The proposed kinetics for irreversible inhibition of organophosphorus compounds on AChE agreed well with the experimental data. The theoretical model of diffusion and reaction in enzyme membrane was presented to analyze the response of sensor signal. Based on the simulation results using the model, the optimal amount of enzyme loaded and substrate was obtained as 80 ㎍ and 6 mM, respectively.

차가버섯 용매추출분획의 Acetylcholinesterase 저해활성에 대한 동역학 및 열역학적 해석

김학규 ( Hak Kyu Kim ),허원 ( Won Hur ),홍억기 ( Eock Kee Hong ),이신영 ( Shin Young Lee ) 한국산업식품공학회 2011 산업 식품공학 Vol.15 No.4

Twenty four fractions by solvent extraction and/or acid precipitation from fruit body and culture broth of Inonotus obliquus were prepared, and their inhibitory effect against acetylcholinesterase (AChE) was investigated. Among these fractions, acid (1 M HCl) precipitates from cell-free culture broth and fruit body exhibited the highest inhibitory effect on AChE in vitro. Acid precipitates inhibited AChE activity in a concentration-dependant manner and IC50 values of both acid precipitates were 0.53 mg/mL. The inhibition pattern was general non-competitive inhibition. The energetic parameters were also determined by dual substrate/temperature design. Both acid precipitates increased the values of Ea, △H, △G and △H* decreasing the value of △S for AChE. The results implied that the acid precipitates from I. obliquus increased the thermodynamic barrier, leading to the breakdown of ES complex and the formation of products as inhibitory mechanism.

인지기능활성을 가진 생약복합물을 첨가한 두유젤리의 제조 및 품질특성

김희숙(Hee-Suk Kim),강진순(Jin-Soon Kang) 한국식품영양과학회 2012 한국식품영양과학회지 Vol.41 No.9

인지기능 활성을 가진 생약복합물을 선정하여 최적조성물을 조제한 다음 생약복합물의 첨가비율을 달리하여(0%,5%, 10%, 15%, 20%) 제조한 두유 젤리의 품질에 미치는 영향을 조사하였다. 인지기능 생약복합물을 일정비율로 첨가하여 제조한 두유 젤리 제품의 수분활성도는 대조군에 비 하여 생약복합물 첨가군이 더 증가하였으며 생약복합물이 많을수록 증가하는 경향이었다. pH는 대조군에 비해 생약복합물 첨가한 젤리에서와 생약복합물의 첨가량에 증가함에 따라 약간 감소하는 경향이었다. 당도는 대조군에 비하여 생약복합물을 첨가한 젤리에서 모두 높게 나타났다. 색도는 두유젤리에 대한 생약복합물의 첨가량이 증가할수록 젤리의 L값은 낮아졌으나 적색도(a)값과 황색도(b)값은 높아졌다. 텍스쳐 측정 결과 경도, 검성, 씹힘성은 생약복합물 15%,20% 첨가군에서 대조군에 비해 유의적으로 증가하였으나 부서짐성, 탄력성, 응집성, 복원성은 전군에서 거의 차이를 보이지 않았다. 또한 관능평가 결과 전반적으로 유의적인 차이가 없는 것으로 나타나 첨가량 20% 범위 이내에서는 인지기능 활성을 고려하여 첨가량을 조절할 수 있는 것으로 나타났다. In this study, soy milk jellys with medicinal herbs (MH) composites showing cognitive effects were prepared and their characteristics were examined. Eight kinds of medicinal herbs were extracted with hot water and added to soy milk based on their contents. Medicinal herbs showed cognitive effects, namely promoting acetylcholinesterase (AChE) inhibition. In the preparation of soy milk jellys containing MH extracts of various contents (0%, 5%, 10%, 15% and 20%), pH of all groups significantly (p<0.05) decreased with increasing MH extracts compared to the control group. The brix of the soy milk jellys was the highest in the 5% content of MH extracts among all groups. The "a" and "b" values of soy milk jellys increased with the content of MH extracts, while the "L" value decreased adding to the content of MH extracts compared to the control. The hardness, gumminess, and chewiness of soy milk jellys were improved the most by the addition of 15~20% MH extracts, while the fracturability, adhesiveness, springiness, cohesiveness, and resilience of soy milk jelly was not significantly different (p<0.05) among all groups. Through a sensory evaluation, it was revealed that the taste, texture, overall preference, flavor, and sweetness of soy milk jellys was not significantly different (p<0.05) among all groups. Therefore, since the addition of 20% MH extracts did not significantly alter the sensory evaluation, it can usually be adjusted to make soy milk jellys with cognitive effects.

Fumigant and Contact toxicity of Myrtaceae Ppant essential oils and Blends of their Constituents against Adults of German Cockroach (Blattella germanica) and their Acetylcholinesterase Inhibitory Activity

Hwa-Jeong Yeom,Jaesoon Kang,Sung-Woong Kim,Seon-Mi Seo,Yoon-Mi Jeon,Il-KwonPark 한국응용곤충학회 2013 한국응용곤충학회 학술대회논문집 Vol.2013 No.04

Fumigant and contact toxicities of 11 Myrtaceae plant essential oils and their constituents against adult male and female Blattella germanica were evaluated. Of 11 Myrtaceae plant essential oils, Eucalyptus polybractea, E. smithii, E. radiata, E. dives, E. globulus, and Melaleuca uncinata, showed 100% fumigant toxicity against adult male German cockroaches at a concentration of 7.5 mg/liter air concentration. In contact toxicity tests, E. polybractea, E. smithii, E. radiata, E. dives, E. globulus, M. dissitiflora, and M. uncinata produced strong insecticidal activity against adult male and female German cockroaches. Of the essential oil constituents, terpinolene, α-terpinene, and terpinen-4-ol demonstrated strong fumigant toxicity against adult male and female B. germanica. Eugenol, isoeugenol, methyl eugenol, and terpinen-4-ol showed strong contact toxicity against adult male B. germanica. The toxicity of the constituent blends identified from M. dissitiflora essential oils indicated that terpinen-4-ol were major contributor to the fumigant activity or contact toxicity of the artificial blend. Only isoeugenol exhibited inhibition activity against male acetylcholinesterase. IC50values of isoeugenol were 0.22 mg/mL against male acetylcholinesterase.

Fumigant and contact toxicity of Myrtaceae plant essential oils and blends of their constituents against adults of German cockroach (Blattella germanica) and their acetylcholinesterase inhibitory activity

Yeom, H.J.,Kang, J.,Kim, S.W.,Park, I.K. Academic Press 2013 Pesticide biochemistry and physiology Vol.107 No.2

Fumigant and contact toxicities of 11 Myrtaceae plant essential oils and their constituents against adult male and female Blattella germanica were evaluated. Of 11 Myrtaceae plant essential oils, Eucalyptus polybractea, Eucalyptussmithii, Eucalyptusradiata, Eucalyptusdives, Eucalyptusglobulus, and Melaleuca uncinata, showed 100% fumigant toxicity against adult male German cockroaches at a concentration of 7.5mg/liter air concentration. In contact toxicity tests, E. polybractea, E. smithii, E. radiata, E. dives, E. globulus, Melaleucadissitiflora, and M. uncinata produced strong insecticidal activity against adult male and female German cockroaches. Of the essential oil constituents, terpinolene, α-terpinene, and terpinen-4-ol demonstrated strong fumigant toxicity against adult male and female B. germanica. Eugenol, isoeugenol, methyl eugenol, and terpinen-4-ol showed strong contact toxicity against adult male B. germanica. The toxicity of the constituent blends identified from M. dissitiflora essential oils indicated that terpinen-4-ol were major contributor to the fumigant activity or contact toxicity of the artificial blend. Only isoeugenol exhibited inhibition activity against male acetylcholinesterase. IC<SUB>50</SUB> values of isoeugenol were 0.22mg/mL against male acetylcholinesterase.

Inhibition of acetylcholinesterase and glutathione S-transferase of the pinewood nematode (Bursaphelenchus xylophilus) by aliphatic compounds

Kang, J.S.,Moon, Y.S.,Lee, S.H.,Park, I.K. Academic Press 2013 Pesticide biochemistry and physiology Vol.105 No.3

To determine the nematicidal mode of action of aliphatic compounds against the pinewood nematode (Bursaphelenchus xylophilus), we evaluated the inhibition activity of 63 aliphatic compounds on B. xylophilus acetylcholinesterases (BxACEs) and glutathione S-transferase. In the primary inhibition assay using B. xylophilus crude proteins, more than 65% of BxACE inhibition activity was observed for C<SUB>6</SUB>, C<SUB>9</SUB>, C<SUB>10</SUB>, and C<SUB>12</SUB> 2E-alkenals. Other compounds showed moderate or weak inhibition activity. The inhibition activity against 3 recombinant BxACEs was subsequently evaluated using active compounds in a primary inhibition assay. C<SUB>12</SUB> 2E-alkenal showed the strongest inhibition activity against BxACE-1, followed by C<SUB>9</SUB>, C<SUB>6</SUB>, and C<SUB>10</SUB> 2E-alkenals. The IC<SUB>50</SUB> values of C<SUB>12</SUB>, C<SUB>6</SUB>, C<SUB>10</SUB>, and C<SUB>9</SUB> 2E-alkenal against BxACE-2 were 0.0059, 0.57, 0.86, and 0.99mg/ml, respectively. C<SUB>12</SUB> 2E-alkenal showed the strongest inhibition activity against BxACE-3 followed by C<SUB>6</SUB> 2E-alkenal. In an inhibition activity test using glutathione S-transferase from the pinewood nematode, C<SUB>10</SUB>, C<SUB>9</SUB>, and C<SUB>6</SUB> 2E-alkenals and C<SUB>12</SUB> alkanoic acid showed >45% inhibition activity.

국내 및 미얀마에서 재배된 삼채뿌리의 항산화, α-Glucosidase 저해 및 Acetylcholinesterase 저해 활성

박주영,윤경영,Park, Joo Young,Yoon, Kyung Young 한국식품저장유통학회 2016 한국식품저장유통학회지 Vol.23 No.2

본 연구는 선행 연구된 삼채뿌리의 뛰어난 영양성을 토대로 기능성 식품소재로의 이용가능성을 확인하고 활용도를 높이고자 국내산 및 미얀마산 삼채뿌리의 항산화 및 생리활성을 측정하였다. 삼채뿌리의 총 폴리페놀과 총 플라보노이드 함량은 국내산 삼채뿌리가 각각 5.27 mgGAE/g, 0.35 mgQE/g, 미얀마산 삼채뿌리가 각각 4.80 mgGAE/g, 0.24 mgQE/g으로 국내산 삼채뿌리가 더 높은 함량을 나타냈다. 삼채뿌리의 항산화력을 측정한 결과 DPPH 라디칼 소거능은 미얀마산이 더 높은 활성을 보였지만, ABTS 라디칼 소거능과 $Fe^{2+}$ 킬레이팅 활성, 환원력은 국내산이 더 높은 활성을 보였다. ${\alpha}-Glucosidase$ 저해활성은 국내산의 저해활성이 미얀마산 삼채뿌리의 저해활성보다 더 높았으며 대조구인 acarbose에 비해서도 우수한 저해활성을 보였다. Acetylcholinesterase 저해 활성을 측정한 결과, 50 mg/mL 농도에서 국내산 삼채뿌리가 51.44%로 44.33%의 저해활성을 보인 미얀마산 삼채뿌리보다 더 높은 저해활성을 보였다. 본 연구를 통해 삼채뿌리 특히 국내산 삼채뿌리는 높은 항산화 활성, ${\alpha}-glucosidase$ 및 acetylcholinesterase 저해 활성을 보여 혈당조절제, 치매예방 및 개선제로써의 활용가능성이 큰 것으로 확인되었으며, 이로써 기능성 식품소재로의 활용이 증가될 것으로 판단된다. 하지만 향후 국내산 삼채의 우수성을 검증하기 위하여 여러 지역에서 재배된 삼채의 기능성 분석이 필요할 것으로 판단된다. This study was conducted to compare the functionality (antioxidant, anti-diabetic, and anti-dementia activities) of the methanol extract of Allium hookeri root grown in Korea (KR) and Myanmar (MR). The total polyphenol and flavonoid contents of KR and MR were 5.27 and 4.80 mg GAE/g, and 0.35 and 0.24 mg QE/g, respectively. KR contained significantly higher levels of total polyphenols and total flavonoids than those of MR (p<0.05). The IC50 values of KR and MR were 6.53 and 5.31 mg/mL, respectively, for DPPH radical scavenging activity. However, KR had a significantly higher ABTS radical scavenging activity, $Fe^{2+}$ chelating ability, and reducing power compared with those of MR (p<0.05). In the evaluation of anti-diabetic activity, KR showed significantly higher ${\alpha}-glucosidase$ inhibition activity than acarbose and MR at whole concentrations (p<0.05). KR and MR had acetylcholinesterase inhibition activities that of 51.44% and 44.33%, respectively, at a 50 mg/mL concentration. These results suggested that roots of A. hookeri, especially KR, could be useful in improving diabetic and dementia disorders due to their high antioxidant, anti-diabetic, and anti-dementia activities.