Silk sericin was found to suppress the production of pro-inflammatory cytokines, which are related to the inflammatory reaction. The objectives of this study were to investigate the anti-inflammatory effect of sericin in vivo using the carrageenan-induced rat edema model and changes in the histology of tissues. The effects of sericin on the expression of COX-2 and iNOS were also evaluated. Sericin solutions at 0.004-0.080 mg/mL were applied topically to the top of the hind paw and carrageenan (1.0 mg) was injected subcutaneously to the plantar surface of the right hind paw. Our results indicated that sericin significantly reduced the inflammation in rats’ paw compared with the negative control (water and acetone) and its effect at 0.080 mg/mL was only slightly lower than that of 1.0% w/v indomethacin. Similar numbers of polymorphonuclear and macrophage cells were found in rats’ tissue treated with indomethacin and sericin solution, while the numbers were significantly higher in their absence. The gene expression results by RT-PCR showed that the COX-2 and iNOS genes were down-regulated in samples treated with sericin in a dose dependent manner. These data indicated that the anti-inflammatory properties of sericin may be partly attributable to the suppression of the COX-2 enzyme and nitric oxide production.
AramwitP, DamrongsakkulS, KanokpanontS, SrichanaT. (2010) Properties and antityrosinase activity of sericin from various extraction methods. Biotechnology and Applied Biochemistry, 55, 91–98.
2.
AramwitP, SangcakulA. (2007) The effects of sericin cream on wound healing in rats. Bioscience Biotechnology & Biochemistry, 71, 2473–2477.
3.
AramwitP, SiritientongT, SrichanaT. (2012) Potential applications of silk sericin, a natural protein from textile industry by-products. Waste Management & Research, 30, 217–224.
ZhaorigetuS, YanakaN, SasakiM, WatanabeH, KatoN. (2003) Inhibitory effects of silk protein, sericin on UVB-induced acute damage and tumor promotion by reducing oxidative stress in the skin of hairless mouse. Journal of Photochemistry and Photobiology B, Biology, 71, 11–17.
AramwitP, KanokpanontS, De-EknamkulW, SrichanaT. (2009) Monitoring of inflammatory mediators induced by silk sericin. Journal of Bioscience and Bioengineering, 107, 556–561.
8.
AramwitP, KanokpanontS, PunyaritP, SrichanaT. (2009) Effectiveness and inflammatory cytokines induced by sericin compared to sericin in combination with silver sulfadiazine cream on wound healing. Wounds, 21, 198–206.
9.
WalportM, DuffG. (1993) Cells and mediators of inflammation. Oxford Testbook of Rheumatology. Oxford, UK, Oxford University Press.
10.
MajnoG, JorisI. (1996) Cells, tissues and disease: Principles of general pathology. Blackwell Science, Cambridge, MA.
11.
OlajideOA, MakindeJM, AweSO. (1999) Effects of the aqueous extract of Bridelia ferruginea stem bark on carrageenan-induced oedema and granuloma tissue formation in rats and mice. Journal of Ethnopharmacology, 66, 113–117.
12.
Di RosaM, GiroudJP, WilloughbyDA. (1971) Studies on the mediators of the acute inflammatory response induced in rats in different sites by carrageenan and turpentine. Journal of Pathology, 104, 15–29.
13.
MorrisCJ. (2003) Carrageenan-induced paw edema in the rat and mouse. Methods in Molecular Biology, 225, 115–121.
14.
VaneJR, BakhleYS, BottingRM. (1998) Cyclooxygenases 1 and 2. Annual Review of Pharmacology and Toxicology, 38, 97–120.
15.
SmithWL, DeWittDL, GaravitoRM. (2000) Cyclooxygenases: structural, cellular, and molecular biology. Annual Review of Biochemistry, 69, 145–182
16.
ZhaoJ, SharmaY, AgarwalR. (1999) Significant inhibition by the flavonoid antioxidant silymarin against 12-O-tetradecanoylphorbol 13-acetate-caused modulation of antioxidant and inflammatory enzymes, and cyclooxygenase 2 and interleukin-1-alpha expression in SENCAR mouse epidermis: implications in the prevention of stage I tumor promotion. Molecular Carcinogenesis, 26, 321–333.
17.
SareilaO, KorhonenR, AuvinenH, HamalainenM, KankaanrantaH, NissinenE, MoilanenE. (2008) Effects of levo- and dextrosimendan on NF-kappaB-mediated transcription, iNOS expression and NO production in response to inflammatory stimuli. British Journal of Pharmacology, 155, 884–895
18.
KorhonenR, LahtiA, KankaanrantaH, MoilanenE. (2005) Nitric oxide production and signaling in inflammation. Current Drug Targets - Inflammation & Allergy, 4, 471–479.
19.
AldertonWK, CooperCE, KnowlesRG. (2001) Nitric oxide synthases: structure, function and inhibition. Biochemical Journal, 357, 593–615.
20.
BiJ, JiangB, ZornA, ZhaoRG, LiuP, AnLJ. (2012) Catalpol inhibits LPS plus IFN-gamma-induced inflammatory response in astrocytes primary cultures. Toxicology in Vitro, 27, 543–550.
21.
LiaoJC, DengJS, LinYC, LeeCY, LeeMM, HouWC, HuangSS, HuangGJ. (2012) Antioxidant, antinociceptive, and anti-inflammatory activities from Actinidia callosa var. callosa in vitro and in vivo. Evidence-Based Complementary and Alternative Medicine, Article ID 129152, 129–152.
22.
HuZQ, ZhaoWH, ShimamuraT. (2007) Regulation of mast cell development by inflammatory factors. Current Medicinal Chemistry14, 3044–3050.
23.
ZaomingW, CodinaR, Fernandez-CaldasE, LockeyRF. (1996) Partial characterization of the silk allergens in mulberry silk extract. Journal of Investigational Allergology and Clinical Immunology, 6, 237–241.
24.
SoongHKKenyonKR. (1984) Adverse reactions to virgin silk sutures in cataract surgery. Ophthalmology, 91, 479–483.
25.
WenCM, YeST, ZhouLX, YuY. (1990) Silk-induced asthma in children: a report of 64 cases. Annals of Allergy, 65, 375–378.
26.
PanilaitisB, AltmanGH, ChenJ, JinHJ, KarageorgiouV, and KaplanDL. (2003) Macrophage responses to silk. Biomaterials, 24, 3079–3085.
27.
WinterCA, RisleyEA, NussGW. (1962) Carrageenin-induced edema in hind paw of the rat as an assay for antiiflammatory drugs. Proceedings of The Society for Experimental Biology and Medicine, 111, 544–547.
28.
VogelHG. (2008) Paw edema in drug discovery and evaluation pharmacological assays. Springer-Verlag, Berlin, Heidelberg, New York.
29.
AramwitP, KanokpanontS, NakphengT, SrichanaT. (2010) The effect of sericin from various extraction methods on cell viability and collagen production. International Journal of Molecular Sciences, 11, 2200–2211.
