Effects of Silk Protein Hydrolysates on Blood Glucose Level, Serum Insulin and Leptin Secretion in OLETF Rats

이영숙,; 박민정,; 최지은,; 김지영,; 남문석,; 정윤화,

doi:10.3746/jkfn.2007.36.6.703

Cited by 20 publications

(9 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…16,17) Most of all, SAA fully prevented gastricnemius muscles from oxidative injury following exhaustive forced exercise, suggestive of its direct muscle-preserving (anti-oxidant) activity. 8,12,16,17) In addition, it is believed that a part of the stamina-improving effect of SAA may come from its anti-fatigue activity, since it recovered blood glucose and proteins depleted by forced swimming exercise. 23,27,30,34) In addition to loss in body and liver weights related to energy depletion, exercise stress causes damage to various tissues and organs.…”

Section: Discussionmentioning

confidence: 99%

“…Hydrolysis of silk proteins from silkworms leads to different peptide sizes, which eventually creates peptides that are 18-19 amino acids in length, while enzymatic degradation results in specific sizes or compositions of peptides 10,11) exerting diverse bioactivities 4,12,13) such as anti-diabetic, [5][6][7][8][9] hypocholesterolemic, 10,14,15) anti-oxidant, 16,17) immunoregulatory, 18) anti-tumor, 17,19) anti-viral, 20) anti-bacterial 21) effects. Silk amino acids (SAA) were also shown to decrease blood triglycerides and to preserve hepatic function.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Silk Amino Acids Improve Physical Stamina and Male Reproductive Function of Mice

Shin

Yeon

Park

et al. 2010

Biological & Pharmaceutical Bulletin

View full text Add to dashboard Cite

Silks are protein polymers that differ in their components and structures according to the insects producing the silk. 1)Silks from silkworm (Bombyx mori) and spiders (Nephila clavipes and Araneus diadematus) are composed of 2 major peptides, sericin and fibroin, 2) which are well known to have pharmacological activities including anti-diabetic effect. [3][4][5][6][7][8][9] Hydrolysis of silk proteins from silkworms leads to different peptide sizes, which eventually creates peptides that are 18-19 amino acids in length, while enzymatic degradation results in specific sizes or compositions of peptides 10,11) exerting diverse bioactivities 4,12,13) such as anti-diabetic, [5][6][7][8][9] hypocholesterolemic, 10,14,15) anti-oxidant, 16,17) immunoregulatory, 18) anti-tumor, 17,19) anti-viral, 20) anti-bacterial 21) effects. Silk amino acids (SAA) were also shown to decrease blood triglycerides and to preserve hepatic function. 10,14) In our previous studies, we found that repeatedly treating resting rats with a SAA preparation lowered blood levels of tissue injury parameters from the muscles and the liver.22) Also, it increased glucose and albumin levels, and potentiated hematopioesis including lymphocyte counts. Furthermore, a high dose (800 mg/kg) of SAA exerted stamina-enhancing activity in forced swimming mice by preventing tissue injuries and increasing anti-fatigue parameters.23) Such effects led us to investigate the effects of a SAA preparation on the physical stamina (energy-boosting) and male reproductive function in a forced swimming model. Forced swimming tests have been used to evaluate the behavioral performances of rodents to predict the efficacy of anti-depressant treatments, [24][25][26] since the animals exhibit immobility behavior considered a depression-like response, as a reflection of helplessness when subjected to an incapable situation.27) Similarly, weight-loaded swimming tests have also been used as a reference for measuring the fatigue level objectively and quantitatively. [28][29][30] Recently, forced swimming tests were adopted not only to assess adjustment of rodents, but also to evaluate male reproductive function under repeated stress situations. [30][31][32][33] The aim of the present study was to determine the effects of SAA, an amino acid preparation from silk (cocoon), on physical stamina and male reproductive function. Especially, we analyzed not only the maximum swimming time and blood and tissue parameters of muscular and hepatic injuries, but also hormone concentration and sperm counts following weight-loaded forced swimming. MATERIALS AND METHODSMaterials A preparation of SAA from acid (HCl) hydrolysate of silk proteins was obtained from Worldway Co., Ltd. (Jeoneui, Korea). The SAA preparation was mainly composed of Ala (34.36%)ϾGly (27.23%)ϾSer (9.58%)Ͼ Val (3.49%)ϾThr (2.00%), and minor amino acids. 23)Animals Eight-week-old male ICR mice (29-31 g, nϭ10 per group) were procured from the Daehan Laboratory Animal Center (Eumseong, Korea). The animals were maintained at a const...

show abstract

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

Silk Amino Acids Improve Physical Stamina and Male Reproductive Function of Mice

Shin

Yeon

Park

et al. 2010

Biological & Pharmaceutical Bulletin

View full text Add to dashboard Cite

show abstract

“…Hydrolysis of silk proteins leads to different sizes of peptide, while enzymatic degradation results in specifi c sizes or compositions of silk peptides (SP) exerting diverse bioactivities including anti-diabetic, hypocholesterolemic and antioxidative actions (Kato et al, 1998;Lee et al, 2002;2007b;Zhaorigetu et al, 2003;Kim et al, 2008). Furthermore, silk amino acids (SAA) enhanced physical stamina by preventing tissues from oxidative injures (Shin et al, 2009a;2009b).…”

Section: Original Articlementioning

confidence: 99%

“…Silks from silkworm (Bombyx mori) are composed of 2 major peptides, sericin and fi broin (Lee et al, 2003), which are well known to have pharmacological activities including antidiabetic effect (Park et al, 2002;Lee et al, 2007b). Hydrolysis of silk proteins leads to different sizes of peptide, while enzymatic degradation results in specifi c sizes or compositions of silk peptides (SP) exerting diverse bioactivities including anti-diabetic, hypocholesterolemic and antioxidative actions (Kato et al, 1998;Lee et al, 2002;2007b;Zhaorigetu et al, 2003;Kim et al, 2008).…”

Section: Original Articlementioning

confidence: 99%

Improving Effect of Silk Peptides on the Cognitive Function of Rats with Aging Brain Facilitated by D-Galactose

Park¹,

Lee²,

Choi³

et al. 2011

Biomolecules and Therapeutics

View full text Add to dashboard Cite

show abstract

“…Moreover, it is well known that increasing the concentration of leptin leads to an exothermic reaction and an increase in the amount of activity. Therefore, SP promotes fat oxidation and increases energy expenditure (15,16). Additionally, in several rat and mouse model studies, food intake and body weight were decreased in rodents fed ad libitum (5,14,16).…”

mentioning

confidence: 99%

Silk Peptide Intake Increases Fat Oxidation at Rest in Exercised Mice

Kim

Hwang

Yun

et al. 2013

J Nutr Sci Vitaminol

View full text Add to dashboard Cite

250Obesity is associated with lifestyle habits such as inactivity, bad eating practices, stress and excessive net intake of calories (1). Among these, energy imbalance and inactivity are becoming serious problems. Total energy cost can be divided into three parts, including resting metabolic rate (RMR), diet-induced thermogenesis (DIT), and the amount of energy used for physical activity energy expenditure (AEE) (2). The greatest component of daily energy expenditure is RMR, constituting about 70% of the total energy expenditure (3, 4).Silk peptides (SP) have been ingested for a long time in Asian countries (5). In recent years, additional applications have been developed for silk, mainly in the field of biotechnology and biomedicine. The versatility of these new implementations arises from the singularity of the molecular structure of silk (6). Proteins such as fibroin and sericin are the main constituents of silk, with fibroin constituting 70 to 80% and sericin 20 to 30% of the total cocoon weight (6, 7).Many studies regarding the health benefits of SP intake have been reported (8-11). SP not only regulate blood glucose level and hyperlipidemia and but also decrease blood triglycerides and LDL cholesterol (12,13). In addition, a high dose (800 mg/kg) of SP was shown to exert stamina-enhancing activity in forced swimming mice by preventing tissue injuries and increasing anti-fatigue (14). Moreover, it is well known that increasing the concentration of leptin leads to an exothermic reaction and an increase in the amount of activity. Therefore, SP promotes fat oxidation and increases energy expenditure (15,16). Additionally, in several rat and mouse model studies, food intake and body weight were decreased in rodents fed ad libitum (5,14,16).However, measurements in those studies have been conducted for analysis of blood profiles and hormones in mice. Accordingly, we investigated the effects of SP administration using an open circuit calorimetry system on resting energy expenditure and substrate utilization in resting mice for 24 h. Materials and MethodsAnimals. Seven-week-old male ICR-mouse (n518) were used. Mice were purchased from Orient Bio Inc. (Seongnam, Korea). All mice were housed in standard plastic cages under controlled conditions of humidity (50%) and temperature (2361˚C) with alternating 12 h cycles of light and dark. Mice were adapted to the laboratory housing conditions for 3 d. They were given free access to water and a non-purified commercial diet (5L79, Orient Bio Inc.) containing (g/kg diet): crude protein, 180; crude fat, 52; crude fiber, 52; minerals, 57; and carbohydrate, 368. The protein, fat, and carbohydrate ratio (%) based on calories was 21 : 14 : 65, and (Received January 11, 2013) Summary Silk peptides (SP) have been reported to decrease body weight and accumulate fat. We investigated the effects of SP administration by using an open circuit calorimetry system on resting energy expenditure and substrate utilization in resting mice for the duration of 24 h. Seven-week-old male ICR-...

show abstract

Effects of Silk Protein Hydrolysates on Blood Glucose Level, Serum Insulin and Leptin Secretion in OLETF Rats

Cited by 20 publications

References 2 publications

Silk Amino Acids Improve Physical Stamina and Male Reproductive Function of Mice

Silk Amino Acids Improve Physical Stamina and Male Reproductive Function of Mice

Improving Effect of Silk Peptides on the Cognitive Function of Rats with Aging Brain Facilitated by D-Galactose

Silk Peptide Intake Increases Fat Oxidation at Rest in Exercised Mice

Contact Info

Product

Resources

About