• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.9
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• pp.1166-1171
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• 2006

This study was performed to investigate the effect of silk protein hydrolysates on blood glucose in diabetic mice (C57BL/KsJ db/db). The silk protein hydrolysates hydrolyzed by protease contains 87.52% of peptides of which molecular weight was below 2,000 dalton. The content of free amino acids was 14.80 g/100 g silk protein hydrolysates and major free amino acids were Pro, Thr, Arg and Ala. Silk protein hydrolysates were administered to the animals for 9 weeks at doses of 0.2, 0.5% and 0.8% solution. The body weight increase in the 0.5 and 0.8% fed groups were higher than control group. Food and water intake in the silk protein hydrolysates fed groups were lower than control group. The weight of liver was not different among groups, while the weight of kidney in control group was higher than silk protein hydrolysates fed groups. The blood glucose level in silk protein hydrolysates fed groups was lower than control group. In the glucose tolerance test, the blood glucose level in control group was the highest at 15 minutes after glucose injection while those in silk protein hydrolysates fed groups were the highest at 30 minutes. Results in this study suggest that silk protein hydrolysates show hypoglycemic effect in C57BL/KsJ db/db mice.

• Journal of Life Science
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• v.31 no.10
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• pp.898-904
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• 2021

Locusta migratoria is a widespread locust species in many parts of the world and is considered an alternative source for the production of protein for value-added ingredients. We previously identified putative antimicrobial peptides derived from L. migratoria through an in silico analysis of its transcriptome. However, its anti-inflammatory effect has not been studied. In this study, we investigated the anti-inflammatory activities of the antimicrobial peptide locustacin (KTHILSFFPSFLPLFLKK-NH₂) derived from L. migratoria on lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells. Locustacin (50, 100, and 200 ㎍/ml) significantly reduced the production of nitric oxide (NO) in LPS-stimulated macrophages without any cytotoxicity. Locustacin also inhibited the mRNA and protein expression of pro-inflammatory mediators, such as inducible NO synthase and cyclooxygenase-2, in contrast to the presence of LPS alone. Locustacin decreased the release of LPS-induced pro-inflammatory cytokines, including interleukin (IL)-6 and IL-1β, and their gene expression in a dose-dependent manner. Furthermore, locustacin (100 and/or 200 ㎍/ml) inhibited phosphorylation levels of extracellular signal regulated kinase, p38, and c-Jun N-terminal kinase. Locustacin also suppressed the degradation of inhibitory kappa B alpha, which was considered to be an inhibitor of nuclear factor kappa B (NF-κB). Collectively, these results demonstrate that locustacin can exert anti-inflammatory effects through the inhibition of mitogen-activated protein kinase (MAPK) phosphorylation, activation of NF-κB, and downstream inflammatory mediators in LPS-stimulated macrophage cells.

• Journal of the Korean Applied Science and Technology
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• v.36 no.3
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• pp.766-778
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• 2019

In this study, Poria cocos bark were extracted by supercritical process, and anti-inflammatory, whitening, and antioxidant effects were measured in comparison with ethanol extract. Also, An effective percutaneous permeation method using a selected formulation of the extract and a drug delivery peptide was proposed. Pachymic acid, known as the anti-cancer and anti-inflammatory compound of the ventricle, is an indicator component and the HPLC analysis shows that the supercritical extract of the pericardium is more than twice that of the Poria cocos bark extract. In order to confirm antioxidative effect of Bombyx mori, DPPH scavenging ability and ABTS scavenging ability test showed that the ethanol extract of Poria cocos Back had lower concentration than the supercritical extract of Poria cocos back. However, RAW 264.7 Measurements of Nitric oxide (NO) production in cells showed lower NO production at the same concentration than the Poria cocos back ethanol extract. In addition, after 72 hours of processing of $20{\mu}g/mL$ of the Poria cocos back extract in B16 melanoma cells, both the intracellular and extracellular melanin extract were effective and the supercritical extract was lower melanin content. No toxicity was observed at the concentration of $800{\mu}g/mL$ in RAW 264.7 cells used in NO production experiments. However, in B16 melanoma cells, even at $50{\mu}g/mL$, both Poria cocos back ethanol extract and supercritical extract showed a survival rate of less than 60%. The liposome formulation and drug delivery peptides were shown to be useful for percutaneous permeation of Supercritical Extract of Poria cocos back using a liposome formulation and a drug delivery peptide. it is expected that there will be great potential for development as a variety of cosmetic materials for Poria cocos back.

• Food Engineering Progress
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• v.21 no.4
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• pp.360-366
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• 2017

Fish skin peptide-loaded liposomes were prepared in 100 mL and 1 L solution as lab scales, and 10 L solution as a prototype scale. The particle size and zeta potential were measured to determine the optimal conditions for the production of fish skin peptide-loaded liposome. The liposome was manufactured by the following conditions: (1) primary homogenization at 4,000 rpm, 8,000 rpm, and 12,000 rpm for 3 minutes; (2) secondary homogenization at 40 watt (W), 60 W, and 80 W for 3 minutes. From this experimental design, the optimal conditions of homogenization were selected as 4,000 rpm and 60 W. For the next step, fish peptides were prepared as the concentrations of 3, 6, and 12% at the optimum manufacturing conditions of liposome and stored at $4^{\circ}C$. Particle size, polydispersion index (pdI), and zeta potential of peptide-loaded liposome were measured for its stability. Particle size increased significantly as manufacture scale and peptide concentration increased, and decreased over storage time. The zeta potential results increased as storage time increased at 10 L scale. In addition, 12% peptide showed the formation of a sediment layer after 3 weeks, and 6% peptide was considered to be the most suitable for industrial application.

• Journal of Life Science
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• v.30 no.12
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• pp.1078-1084
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• 2020

Protaetia brevitarsis seulensis is an insect belonging to the order Coleoptera. This insect is reported to contain large amounts of physiologically active substances useful for liver protective effect and improvements in blood circulation as well as a broad source of edible protein. Antimicrobial peptides (AMPs) are found in a variety of species, from microorganisms to mammals, and play an important role in the innate immune systems of living things. Microglia are the main source of proinflammatory cytokines and nitric oxide (NO) in the central nervous system. Activated microglia secrete large amounts of neuroinflammatory mediators (e.g., TNF-α, NO, and ROS), which are the main cause of neuronal cell death. In the present study, we investigated the inhibitory effect of Protaetiamycine 6 (PKARKLQKLSAYKTTLRN-NH2), an AMP derived from Protaetia brevitarsis seulensis, on LPS-induced neuroinflammation in BV-2 microglia. Protaetiamycine 6 significantly inhibited NO production without cytotoxicity and decreased the expression levels of inducible NO synthase and cyclooxygenase-2. In addition, Protaetiamycine 6 also reduced the production of neuroinflammatory cytokines on activated BV-2 microglia. These results suggest that Protaetiamycine 6 could be a good source of functional substance to prevent neuroinflammation and neurodegenerative diseases.

• Journal of Life Science
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• v.31 no.11
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• pp.987-994
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• 2021

Our previous studies have reported that antimicrobial peptides (AMPs) derived from the larvae of white-spotted flower chafer (Protaetia brevitarsis seulensis) exert anti-inflammatory and neuroprotective activities. This study explored the anti-inflammatory effects of protaetiamycine 9 (CVLKKAYFLTNLKLRG-NH₂), a novel AMP, derived from P. b. seulensis against lipopolysaccharide (LPS)-mediated inflammatory response in RAW264.7 macrophage cells. Protaetiamycine 9 (25, 50, 75, and 100 ㎍/ml) did not cause cytotoxic effects against RAW264.7 cells. The RAW264.7 cells were pre-treated with various concentrations of protaetiamycine 9 (25-100 ㎍/ml) for 1 hr and then exposed to LPS (100 ng/ml) for 24 hr. Protaetiamycine 9 treatments decreased the LPS-induced secretion of inflammatory mediators, such as nitric oxide (NO), in a dose-dependent manner. Protaetiamycine 9 (25-100 ㎍/ml) effectively downregulated the LPS-induced increase in mRNA and the protein expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2), which are involved in the production of inflammatory mediators. Protaetiamycine 9 also suppressed the production and gene expression of pro-inflammatory cytokines, including interleukin (IL)-6 and IL-1β, compared to the presence of LPS alone. Furthermore, protaetiamycine 9 inhibited the degradation of inhibitory kappa B alpha (IκB-α) and the phosphorylation of mitogen-activated protein kinases (MAPKs), such as extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38. In conclusion, these results suggest that protaetiamycine 9 exhibits LPS-mediated inflammatory responses by blocking IκB-α degradation and MAPK phosphorylation.

• Journal of the Korean Society of Radiology
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• v.84 no.3
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• pp.638-652
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• 2023

Purpose To investigate the MRI markers for the prediction of amyloid β (Aβ)-positivity in mild cognitive impairment (MCI) and Alzheimer's disease (AD), and to evaluate the differences in MRI markers between Aβ-positive (Aβ [+]) and -negative groups using the machine learning (ML) method. Materials and Methods This study included 139 patients with MCI and AD who underwent amyloid PET-CT and brain MRI. Patients were divided into Aβ (+) (n = 84) and Aβ-negative (n = 55) groups. Visual analysis was performed with the Fazekas scale of white matter hyperintensity (WMH) and cerebral microbleeds (CMB) scores. The WMH volume and regional brain volume were quantitatively measured. The multivariable logistic regression and ML using support vector machine, and logistic regression were used to identify the best MRI predictors of Aβ-positivity. Results The Fazekas scale of WMH (p = 0.02) and CMB scores (p = 0.04) were higher in Aβ (+). The volumes of hippocampus, entorhinal cortex, and precuneus were smaller in Aβ (+) (p < 0.05). The third ventricle volume was larger in Aβ (+) (p = 0.002). The logistic regression of ML showed a good accuracy (81.1%) with mini-mental state examination (MMSE) and regional brain volumes. Conclusion The application of ML using the MMSE, third ventricle, and hippocampal volume is helpful in predicting Aβ-positivity with a good accuracy.

• Journal of Sericultural and Entomological Science
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• v.16 no.1
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• pp.21-48
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• 1974

The studies were carried out to disclose the physical and chemical properties of sericin fraction obtained from silk cocoon shells and its characteristics of swelling and solubility. The following results were obtained. 1. The physical and chemical properties of sericin fraction. 1) In contrast to the easy water soluble sericin, the hard soluble sericin contains fewer amino acids include of polar side radical while the hard soluble amino acid sach as alanine and leucine were detected. 2) The easy soluble amino acids were found mainly on the outer part of the fibroin, but the hard soluble amino acids were located in the near parts to the fibroin. 3) The swelling and solubility of the sericin could be hardly assayed by the analysis of the amino acid composition, and could be considered to tee closely related to the compound of the sericin crystal and secondary structure. 4) The X-ray patterns of the cocoon filament were ring shape, but they disappeared by the degumming treatment. 5) The sericin of tussah silkworm (A. pernyi), showed stronger circular patterns in the meridian than the regular silkworm (Bombyx mori). 6) There was no pattern difference between Fraction A and B. 7) X-ray diffraction patterns of the Sericin 1, ll and 111 were similar except interference of 8.85A (side chain spacing). 8) The amino acids above 150 in molecular weight such as Cys. Tyr. Phe. His. and Arg. were not found quantitatively by the 60 minutes-hydrolysis (6N-HCI). 9) The X-ray Pattern of 4.6A had a tendency to disappear with hot-water, ether, and alcohol treatment. 10) The partial hydrolysis of sericin showed a cirucular interference (2A) on the meridian. 11) The sericin pellet after hydrolysis was considered to be peptides composed with specific amino acids. 12) The decomposing temperature of Sericin 111 was higher than that of Sericin I and II. 13) Thermogram of the inner portioned sericin of the cocoon shell had double endothermic peaks at 165$^{\circ}C$, and 245$^{\circ}C$, and its decomposing temperature was higher than that of other portioned sericin. 14) The infrared spectroscopic properties among sericin I, II, III and sericin extracted from each layer portion of the cocoon shell were similar. II. The characteristics of seriein swelling and solubility related with silk processing. 1) Fifteen minutes was required to dehydrate the free moisture of cocoon shells with centrifugal force controlled at 13${\times}$10$^4$ dyne/g at 3,000 R.P.M. B) It took 30 minutes for the sericin to show positive reaction with the Folin-Ciocaltue reagent at room temperature. 3) The measurable wave length of the visible radiation was 500-750m${\mu}$, and the highest absorbance was observed at the wave length of 650m${\mu}$. 4) The colorimetric analysis should be conducted at 650mu for low concentration (10$\mu\textrm{g}$/$m\ell$), and at 500m${\mu}$ for the higher concentration to obtain an exact analysis. 5) The absorbing curves of sericin and egg albumin at different wave lengths were similar, but the absorbance of the former was slightly higher than that of the latter. 6) The quantity of the sericin measured by the colorimetric analysis, turned out to be less than by the Kjeldahl method. 7) Both temperature and duration in the cocoon cooking process has much effect on the swelling and solubility of the cocoon shells, but the temperature was more influential than the duration of the treatment. 8) The factorial relation between the temperature and the duration of treatment of the cocoon cooking to check for siricin swelling and solubility showed that the treatment duration should be gradually increased to reach optimum swelling and solubility of sericin with low temperature(70$^{\circ}C$) . High temperature, however, showed more sharp increase. 9) The more increased temperature in the drying of fresh cocoons, the less the sericin swelling and solubility were obtained. 10) In a specific cooking duration, the heavier the cocoon shell is, the less the swelling and solubility were obtained. 11) It was considered that there are differences in swelling or solubility between the filaments of each cocoon layer. 12) Sericin swelling or solubility in the cocoon filament was decreased by the wax extraction.. 13) The ionic surface active agent accelerated the swelling and solubility of the sericin at the range of pH 6-7. 14) In the same conditions as above, the cation agent was absorbed into the sericin. 15) In case of the increase of Ca ang Mg in the reeling water, its pH value drifted toward the acidity. 16) A buffering action was observed between the sericin and the water hardness constituents in the reeling water. 17) The effect of calcium on the swelling and solubility of the sericin was more moderate than that of magnecium. 18) The solute of the water hardness constituents increased the electric conductivity in the reeling water.

• Clinical and Experimental Reproductive Medicine
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• v.23 no.3
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• pp.247-268
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• 1996

It has been known for a long time that gonadotropins and steroid hormones play a pivotal role in a series of reproductive biological phenomena including the maturation of ovarian follicles and oocytes, ovulation and implantation, maintenance of pregnancy and fetal growth & development, parturition and mammary development and lactation. Recent investigations, however, have elucidated that in addition to these classic hormones, multiple growth factors also are involved in these phenomena. Most growth factors in reproductive organs mediate the actions of gonadotropins and steroid hormones or synergize with them in an autocrine/paracrine manner. The insulin-like growth factor(IGF) system, which is one of the most actively investigated areas lately in the reproductive organs, has been found to have important roles in a wide gamut of reproductive phenomena. In the present communication, published literature pertaining to the intrauterine IGF system will be reviewed preceded by general information of the IGF system. The IGF family comprises of IGF-I & IGF-II ligands, two types of IGF receptors and six classes of IGF-binding proteins(IGFBPs) that are known to date. IGF-I and IGF-II peptides, which are structurally homologous to proinsulin, possess the insulin-like activity including the stimulatory effect of glucose and amino acid transport. Besides, IGFs as mitogens stimulate cell division, and also play a role in cellular differentiation and functions in a variety of cell lines. IGFs are expressed mainly in the liver and messenchymal cells, and act on almost all types of tissues in an autocrine/paracrine as well as endocrine mode. There are two types of IGF receptors. Type I IGF receptors, which are tyrosine kinase receptors having high-affinity for IGF-I and IGF-II, mediate almost all the IGF actions that are described above. Type II IGF receptors or IGF-II/mannose-6-phosphate receptors have two distinct binding sites; the IGF-II binding site exhibits a high affinity only for IGF-II. The principal role of the type II IGF receptor is to destroy IGF-II by targeting the ligand to the lysosome. IGFs in biological fluids are mostly bound to IGFBP. IGFBPs, in general, are IGF storage/carrier proteins or modulators of IGF actions; however, as for distinct roles for individual IGFBPs, only limited information is available. IGFBPs inhibit IGF actions under most in vitro situations, seemingly because affinities of IGFBPs for IGFs are greater than those of IGF receptors. How IGF is released from IGFBP to reach IGF receptors is not known; however, various IGFBP protease activities that are present in blood and interstitial fluids are believed to play an important role in the process of IGF release from the IGFBP. According to latest reports, there is evidence that under certain in vitro circumstances, IGFBP-1, -3, -5 have their own biological activities independent of the IGF. This may add another dimension of complexity of the already complicated IGF system. Messenger ribonucleic acids and proteins of the IGF family members are expressed in the uterine tissue and conceptus of the primates, rodents and farm animals to play important roles in growth and development of the uterus and fetus. Expression of the uterine IGF system is regulated by gonadal hormones and local regulatory substances with temporal and spatial specificities. Locally expressed IGFs and IGFBPs act on the uterine tissue in an autocrine/paracrine manner, or are secreted into the uterine lumen to participate in conceptus growth and development. Conceptus also expresses the IGF system beginning from the peri-implantation period. When an IGF family member is expressed in the conceptus, however, is determined by the presence or absence of maternally inherited mRNAs, genetic programming of the conceptus itself and an interaction with the maternal tissue. The site of IGF action also follows temporal (physiological status) and spatial specificities. These facts that expression of the IGF system is temporally and spatially regulated support indirectly a hypothesis that IGFs play a role in conceptus growth and development. Uterine and conceptus-derived IGFs stimulate cell division and differentiation, glucose and amino acid transport, general protein synthesis and the biosynthesis of mammotropic hormones including placental lactogen and prolactin, and also play a role in steroidogenesis. The suggested role for IGFs in conceptus growth and development has been proven by the result of IGF-I, IGF-II or IGF receptor gene disruption(targeting) of murine embryos by the homologous recombination technique. Mice carrying a null mutation for IGF-I and/or IGF-II or type I IGF receptor undergo delayed prenatal and postnatal growth and development with 30-60% normal weights at birth. Moreover, mice lacking the type I IGF receptor or IGF-I plus IGF-II die soon after birth. Intrauterine IGFBPs generally are believed to sequester IGF ligands within the uterus or to play a role of negative regulators of IGF actions by inhibiting IGF binding to cognate receptors. However, when it is taken into account that IGFBP-1 is expressed and secreted in primate uteri in amounts assessedly far exceeding those of local IGFs and that IGFBP-1 is one of the major secretory proteins of the primate decidua, the possibility that this IGFBP may have its own biological activity independent of IGF cannot be excluded. Evidently, elucidating the exact role of each IGFBP is an essential step into understanding the whole IGF system. As such, further research in this area is awaited with a lot of anticipation and attention.