A Comparison of the Intestinal Absorption of Amino Acids in Piglets When Provided in Free Form or as a Dipeptide

Li, Defa,Zhao, X.H.,Yang, T.B.,Johnson, E.W.,Thacker, P.A. Asian Australasian Association of Animal Productio 1999 Animal Bioscience Vol.12 No.6

Three 28 day-old $Duroc{\times}Large$ $White{\times}Landrace$ litter mate gilts weighing an average of 6.5 kg were used to study the intestinal absorption of amino acids when provided in dipeptide form or in the form of a free amino acid mixture. The pigs were given one of three treatments. The control involved a duodenal infusion containing no amino-acids (phosphate buffer plus 5% sorbitol) while the remaining two treatments involved either a duodenal infusion containing a glycine-lysine dipeptide (1 g) or a mixture of the free amino acids glycine and lysine at the same concentration as in the dipeptide. Blood was drawn from a cannula inserted in the portal vein, at 5 to 20 minute intervals, for two hours following infusion. The concentration of intact dipeptide as well as free glycine and lysine in the portal blood was determined by high performance liquid chromatography. The intact dipeptide was never detected in the portal blood at any time after infusion. Lysine appeared in the portal blood more rapidly after infusion of dipeptide than after infusion of free lysine and the concentration of lysine in portal blood was higher in the pig infused with the dipeptide than after infusion of free lysine at almost all time points measured. The cumulative absorption of lysine and glycine from the intestine during the two hour period after infusion was greater in the pig infused with dipeptide than in the pig infused with free amino acids. The results suggest that although intact dipeptide did not reach he portal circulation, a special transport mechanism for absorption of dipeptide by intestinal cells appears to be present in pigs similar to that observed in other species.

Transport of Sulfanilic Acid via Microbial Dipeptide Transport System

Hwang, Se Young,Ki, Mi Ran,Cho, Suk Young,Yoo, Ick Dong 한국미생물 · 생명공학회 1995 Journal of microbiology and biotechnology Vol.5 No.6

Sulfanilic acid (4-aminobenzenesulfonic acid) alone is normally not permeant in bacteria but can be readily delivered via the microbial dipeptide transport system. A dipeptidyl derivative of this compound, L-phenylalanyl-L-2-sulfanilylglycine (PSG), prepared by attachment of its primary amino group to the phenylalanyl α-glycine moiety, appeared to have a Km of 0.125 mM and a Vmax of 1.9 nmoles/㎖/min (A_660, 1.0) in Escherichia coli. From competitive spectrophotometric analysis, it was found that the type of amino acids in both of the N-and C-terminals affected the kinetic power of dipeptides. The growth inhibitory effect of PSG was over 7 times more potent than that of the sulfanilic acid against E. coli, suggesting that this potential inhibition was presumably due to the increased hydrophobic nature of the sulfanilyl dipeptide.

Crystal Structure and Spectroscopic Properties of Cyclic Dipeptide: A Racemic Mixture of cyclo(D-Prolyl-L-Tyrosyl) and cyclo(L-Prolyl-D-Tyrosyl)

홍영표,Sung-Hong Lee,최종하,Ayana Kashima,Go Nakamura,Takayoshi Suzuk 대한화학회 2014 Bulletin of the Korean Chemical Society Vol.35 No.8

Two diastereoisomers of cyclo(Pro-Tyr) have been synthesized simultaneously. The crystal structures and conformations of both cyclo(L-Pro-L-Tyr) and a racemic mixture of cyclo(D-Pro-L-Tyr) and cyclo(L-Pro-DTyr), abbreviated as rac-cyclo(D-Pro-L-Tyr/L-Pro-D-Tyr), have been determined by a single-crystal X-ray diffraction study at low temperature. The crystals of rac-cyclo(D-Pro-L-Tyr/L-Pro-D-Tyr) belong to orthorhombic space group Pna21 with a = 10.755 (1), b = 12.699 (1), c = 9.600 (1) Å and Z = 4. The tyrosine side chain is folded towards the diketopiperazine (DKP) ring. The DKP ring adopts a twist boat conformation with pseudo symmetry C2v. The pyrrolidine ring has an envelope conformation with the N5, C4, C7 and C8 atoms in a plane. The crystal of rac-cyclo(D-Pro-L-Tyr/L-Pro-D-Tyr) is stabilized by hydrogen bonds between amide N2-H2 and carbonyl oxygen O2 in the neighbor. The hydroxyl group of tyrosine residue is also hydrogen bonded to the oxygen of the carbonyl group of the DKP ring in the next molecule. The spectroscopic properties of both isomers are also described.

흰쥐의 실험적 규폐결절에서 교차결합-46 KDa 단백질의 확인

김유미,김영진,이수영 大韓産業醫學會 2003 대한직업환경의학회지 Vol.15 No.2

목적: 유리규산에 의해 유발되는 흰쥐 폐의 병 발생기전과 관련이 있는 세포들의 반응을 추구하기 위하여 이 연구를 행하였다. 방법: 500㎕의 생리식염수에 50 mg의 유리규산(S:O_2, 0.15~10㎛)을 부유시켜 체중 200 g 내외의 Sprague-Dawley 희쥐들의 기도내에 주입하여 규폐증을 유발시켰다. 규폐결절을 유리규산 주입 후 4주째에 흰쥐 폐에서 적출하였고, 이 결절들은 2%SDS, 10 M urea, 40 mM DTT를 함유한 용액속에서 4일 동안 110℃로 끓였다. 불용성 세포성 피막들은 4~12% 농도 기울기로 SDS-PAGE에서 전기 영동하였고 또한 아미노산 조성을 분석하였다. 대조군 폐와 규폐결절의 균질액의 상청액과 정상 흰쥐의 혈장을 흰쥐의 규폐결절의 교차결합 단백질에 대한 토끼 항체를 사용하여 친화성 크로마토그라피를 행하였다. 대조군 폐와 규폐결절 내 N^ε-(γ-glutamyl) lysine 교차결합의 량은 각각 HPLC 분석법을 사용하여 정량분석하였다. 결과: 교차결합 단백질은 10 M urea와 40 mM sulfhydrgl 시약내에서 오랫동안 끓여도 불용성으로 남아있었다. 피막은 단백질 내 유리규산 입자의 잔여물로서 alanine, leucine 및 glycine의 함량이 높았다. 46 KDa 단백질은 규폐결절 내 교차결합 단백질임을 친화성 크로마토그라피 방법으로 증명하였다. 규폐결절 내 N^ε-(γ-glutamyl) lysine dipeptide의 양은 대조군 폐의 량에 비하여 현저하게 증가되었다. 결론: Transglutaminase에 의하여 촉매화된 교차결합은 규폐결절 형성에 관여하며, 46 KDa 단백질은 섬유화와 섬유화로 인한 규폐결절 형성 동안 다른 세포 밖의 마트릭스 단백질 및 그 자체 단백질 내의 교차결합물인 것 같다. Objectives: This study was conducted in order to understand the cellular events associated with silica-induced pathogenesis of the rat lung. Methods: Silicosis was induced by an intratracheal instillation of 50 mg of silica (S:O_2, 0.15~10㎛) suspended in 500 ㎕ of a sterile saline solution in Sprague-Dawley rats weighing 200 g. Silicotic nodules were excised from the rat lungs 4 weeks after silica instillation, then boiled for 4 days at 110℃ in solution containing 2% SDS, 10 M urea and 40 mM DTT. The insoluble cellular encapsulates were electrophoresed on 4~12% gradient SDS-PAGE, and the amino acid composition was analyzed. Affinity chromatographies of the homogenate supernatants of the control lung, silicotic nodule, and normal rat plasma were performed using rabbit anti-rat cross-linked protein from the silicotic nodule IgG. The amounts of N^ε-(γ-glutamyl) lysine cross-link in the control lungs and silicotic nodules were determined using HPLC analysis. Results: The remaining cross-linked protein was insoluble in the 10 M urea and 40 mM sulfhydryl reagents even under prolonged boiling conditions. The encapsulate revealed the retention of silica particles within the protein whose amino acid composition showed a high percentage of alanine, leucine and glycine. A 46KDa protein was identified as a cross-linked protein in the silicotic nodule by affinity chromatography. The level of N^ε-(γ-glutamyl) lysine dipeptide in the nodule digest was prominently increased compared with that in the control lung. Conclusions: Transglutaminase(TGase)-catalyzed cross-linking appears to be involved in the silicotic nodule formation, and the 46KDa protein may be cross-linked to itself and other extracellular matrix proteins during fibrosis and the formation of eventually insoluble nodule.

Crystal Structure and Spectroscopic Properties of Cyclic Dipeptide: A Racemic Mixture of cyclo(ᴅ-Prolyl-ʟ-Tyrosyl) and cyclo(ʟ-Prolyl-ᴅ-Tyrosyl)

Hong, Yong Pyo,Lee, Sung-Hong,Choi, Jong-Ha,Kashima, Ayana,Nakamura, Go,Suzuki, Takayoshi Korean Chemical Society 2014 Bulletin of the Korean Chemical Society Vol.35 No.8

Two diastereoisomers of cyclo(Pro-Tyr) have been synthesized simultaneously. The crystal structures and conformations of both cyclo($\small{L}$-Pro-$\small{L}$-Tyr) and a racemic mixture of cyclo($\small{D}$-Pro-$\small{L}$-Tyr) and cyclo($\small{L}$-Pro-$\small{D}$-Tyr), abbreviated as rac-cyclo($\small{D}$-Pro-$\small{L}$-Tyr/$\small{L}$-Pro-$\small{D}$-Tyr), have been determined by a single-crystal X-ray diffraction study at low temperature. The crystals of rac-cyclo($\small{D}$-Pro-$\small{L}$-Tyr/$\small{L}$-Pro-$\small{D}$-Tyr) belong to orthorhombic space group $Pna2_1$ with a = 10.755 (1), b = 12.699 (1), c = 9.600 (1) ${\AA}$ and Z = 4. The tyrosine side chain is folded towards the diketopiperazine (DKP) ring. The DKP ring adopts a twist boat conformation with pseudo symmetry $C_{2v}$. The pyrrolidine ring has an envelope conformation with the N5, C4, C7 and C8 atoms in a plane. The crystal of rac-cyclo($\small{D}$-Pro-$\small{L}$-Tyr/$\small{L}$-Pro-$\small{D}$-Tyr) is stabilized by hydrogen bonds between amide N2-H2 and carbonyl oxygen O2 in the neighbor. The hydroxyl group of tyrosine residue is also hydrogen bonded to the oxygen of the carbonyl group of the DKP ring in the next molecule. The spectroscopic properties of both isomers are also described.

Effect of moisturizer containing autophagy-enhancing peptide on atopic dermatitis: A randomized controlled trial

( Ji Young Choi ),( Soon Hyo Kwon ),( Chae Jin Lim ),( Juyeon Jung ),( Heung Jae Kim ),( Keedon Park ),( Jung Won Shin ),( Chang Hun Huh ),( Kyoung Chan Park ),( Jung Im Na ) 대한피부과학회 2018 대한피부과학회 학술발표대회집 Vol.70 No.2

Background: The use of moisturizer is an essential part of atopic dermatitis (AD) treatment. Pentasodiumtetracarboxymethyl palmitoyl dipeptide-12 (PTPD-12), a newly-synthesized peptide, enhances autophagy activity, thereby modulating inflammation. Objectives: To determine the effect of new moisturizer containing PTPD-12 in the treatment of mild-to-moderate AD. Methods: In this double-blind, randomized, placebocontrolled trial, 43 patients with mild-to-moderate AD were randomly assigned to the moisturizer containing PTPD-12 or control product. Evaluations were performed at baseline, week 2 and week 4 including SCORAD index score, corneometry, trans-epidermal water loss (TEWL), visual analogue scale (VAS) for pruritus, 7-point investigator’s global assessment (IGA), and adverse events. Results: The PTPD-12 group showed significant improvement in terms of SCORAD score, skin hydration, TEWL and pruritus at week 2 and week 4 compared with baseline. Though the control group also showed significant improvement in the SCORAD score and skin hydration, no significant change in TEWL or pruritus was demonstrated. The mean changes in the SCORAD index score, skin hydration, TEWL, pruritus, and the number of patients with improvement in IGA were not statistically different between the two groups. Conclusion: The moisturizer with autophagy-stimulating property provides a good therapeutic option to mild-to-moderate atopic dermatitis by contributing to skin barrier restoration and control of inflammation.

Comparison of Growth Performance and Whole-body Amino Acid Composition in Red Seabream (Pagrus major) Fed Free or Dipeptide Form of Phenylalanine

Kim, Sung-Sam,Rahimnejad, Samad,Song, Jin-Woo,Lee, Kyeong-Jun Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.8

This study was conducted to evaluate the efficacy of the dipeptide form of phenylalanine as a new source of amino acid in terms of growth performance and whole-body amino acid composition in comparison to the free form for red seabream (Pagrus major). Fish ($1.46{\pm}0.001g$) were fed four isonitrogenous and isocaloric experimental diets containing 0.7 or 1.4% phenylalanine either in free or dipeptide form. A feeding trial was carried out in three replicates and the fish were fed to apparent satiation for six weeks. At the end of the feeding trial, feed intake of fish was influenced by both phenylalanine form and level and significantly higher values were obtained at an inclusion level of 0.7% and by the use of dipeptide form. However, the other growth parameters did not significantly differ among treatments. Whole-body amino acid compositions revealed no significant changes in concentrations of both essential and non-essential amino acids regardless of the increase in phenylalanine levels or the use of its different forms. The finding in this study indicates that juvenile red seabream can utilize dipeptide phenylalanine as efficiently as free form without any undesirable effects on growth performance or whole-body amino acid composition.

Dipeptides Inhibit M elanin Synthesis in Mel-Ab Cells through Down Regulation of Tyrosinase

Hyun-e Lee,Eun-Hyun Kim,Hye-Ryung Choi,손의동,윤혜영,백광진,권년수,박경찬,김동석 대한약리학회 2012 The Korean Journal of Physiology & Pharmacology Vol.16 No.4

This study investigated the effects of proline-serine (PS) and valine-serine (VS) dipeptides on melanogenesis in Mel-Ab cells. Proline-serine and VS significantly inhibited melanin synthesis in a concentration-dependent manner, though neither dipeptide directly inhibited tyrosinase activity in a cell-free system. Both PS and VS down-regulated the expression of microphthalmia-associated transcription factor (MITF) and tyrosinase. In a follow-up study also described here, the effects of these dipeptides on melanogenesis-related signal transduction were quantified. Specifically, PS and VS induced ERK phosphorylation, though they had no effect on phosphorylation of the cAMP response element binding protein (CREB). These data suggest that PS and VS inhibit melanogenesis through ERK phosphorylation and subsequent down-regulation of MITF and tyrosinase. Properties of these dipeptides are compatible with application as skin-whitening agents.

Dipeptides Inhibit Melanin Synthesis in Mel-Ab Cells through Down-Regulation of Tyrosinase

Lee, Hyun-E,Kim, Eun-Hyun,Choi, Hye-Ryung,Sohn, Uy-Dong,Yun, Hye-Young,Baek, Kwang-Jin,Kwon, Nyoun-Soo,Park, Kyoung-Chan,Kim, Dong-Seok The Korean Society of Pharmacology 2012 The Korean Journal of Physiology & Pharmacology Vol.16 No.4

This study investigated the effects of proline-serine (PS) and valine-serine (VS) dipeptides on melanogenesis in Mel-Ab cells. Proline-serine and VS significantly inhibited melanin synthesis in a concentration-dependent manner, though neither dipeptide directly inhibited tyrosinase activity in a cell-free system. Both PS and VS down-regulated the expression of microphthalmia-associated transcription factor (MITF) and tyrosinase. In a follow-up study also described here, the effects of these dipeptides on melanogenesis-related signal transduction were quantified. Specifically, PS and VS induced ERK phosphorylation, though they had no effect on phosphorylation of the cAMP response element binding protein (CREB). These data suggest that PS and VS inhibit melanogenesis through ERK phosphorylation and subsequent down-regulation of MITF and tyrosinase. Properties of these dipeptides are compatible with application as skin-whitening agents.

A new cyclic dipeptide penicimutide: the activated production of cyclic dipeptides by introduction of neomycin-resistance in the marine-derived fungus Penicillium purpurogenum G59

Nan Wang,Cheng-Bin Cui,Chang-Wei Li 대한약학회 2016 Archives of Pharmacal Research Vol.39 No.6

A novel cyclic dipeptide, named penicimutide(1), and four known cyclic dipeptides, cyclo(L-Val-L-Pro)(2), cyclo(L-Ile-L-Pro) (3), cyclo(L-Leu-L-Pro) (4) andcyclo(L-Phe-L-Pro) (5), were isolated from a neomycinresistantmutant of the marine-derived fungus Penicilliumpurpurogenum G59. The structure of 1, including theabsolute configuration, was determined by spectroscopicand chemical methods, especially NMR and Marfey’sanalysis. An unusual amino acid in 1, 4,5-didehydro-Lleucine,was found for the first time occurring in nature. HPLC–ESI–MS analysis evidenced that 1–3 were producedonly in the mutant strain, but 4 and 5 were producedin both the mutant and parental strains, indicating that theintroduction of neomycin-resistance in the mutant activatedpathways of 1–3 biosynthesis that were silent in the parentalstrain. Compound 1 selectively inhibited HeLa cells(among five tested human cancer cell lines) with an inhibitionrate (IR %) of 39.4 % at 100 lg/mL, a similarinhibition intensity to that of the positive control 5-fluorouracil(IR % of 41.4 % at 100 lg/mL against HeLacells). The present work exemplifies the effectiveness ofour previous DMSO-mediated method for introducingdrug-resistance in fungi to activate silent biosyntheticpathways to obtain new bioactive compounds.