• 제목/요약/키워드: toll like receptors

검색결과 123건 처리시간 0.015초

Differential Expression of Th1- and Th2- Type Cytokines in Peripheral Blood Mononuclear Cells of Murrah Buffalo (Bubalus Bubalis) on TLR2 Induction by B. Subtilis Peptidoglycan

  • Shah, Syed M.;Ravi Kumar, G.V.P.P.S.;Brah, G.S.;Santra, Lakshman;Pawar, Hitesh
    • Asian-Australasian Journal of Animal Sciences
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    • 제25권7호
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    • pp.1021-1028
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    • 2012
  • Peripheral blood mononuclear cells (PBMCs) discriminate microbial pathogens and induce T-cell responses of appropriate effector phenotype accordingly. Toll-like receptors (TLRs), in part, mediate this microbial recognition and differentiation while the development of T-cell effector functions critically depends on the release of Th1- or Th2- type cytokines. In the present study, buffalo PBMCs were stimulated under in vitro culture conditions by Bacillus subtilis cell wall petidoglycan, a TLR2 ligand, in a dose- and time- dependent manner. The expression of TLR2 as well as the subsequent differential induction of the Th1 and Th2 type cytokines was measured. Stimulation was analyzed across five doses of peptidoglycan ($10{\mu}g/ml$, $20{\mu}g/ml$, $30{\mu}g/ml$, $40{\mu}g/ml$ and $50{\mu}g/ml$) for 3 h, 12 h, 24 h and 36 h incubation periods. We observed the induction of TLR2 expression in a dose- and time-dependent manner and the peptidoglycan induced tolerance beyond $30{\mu}g/ml$ dose at all incubation periods. The correlation between peptidoglycan stimulation and TLR2 induction was found positive at all doses and for all incubation periods. Increased production of all the cytokines was observed at low doses for 3 h incubation, but the expression of IL-4 was relatively higher than IL-12 at the higher antigen doses, indicating tailoring towards Th2 response. At 12 h incubation, there was a pronounced decrease in IL-4 and IL-10 expression relative to IL-12 in a dose- dependent manner, indicating skewing to Th1 polarization. The expression of IL-12 was highest for all doses across all the incubation intervals at 24 h incubation, indicating Th1 polarization. The relative expression of TNF-${\alpha}$ and IFN-${\gamma}$ was also higher while that of IL-4 and IL-10 showed a decrease. For 36 h incubation, at low doses, relative increase in the expression of IL-4 and IL-10 was observed which decreased at higher doses, as did the expression of all other cytokines. The exhaustion of cytokine production at 36 h indicated that PBMCs became refractory to further stimulation. It can be concluded from this study that the cytokine response to sPGN initially was of Th2 type which skews, more pronouncedly, to Th1 type with time till the cells become refractory to further stimulation.

Effect of Vitamin E Supplementation on Intestinal Barrier Function in Rats Exposed to High Altitude Hypoxia Environment

  • Xu, Chunlan;Sun, Rui;Qiao, Xiangjin;Xu, Cuicui;Shang, Xiaoya;Niu, Weining;Chao, Yu
    • The Korean Journal of Physiology and Pharmacology
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    • 제18권4호
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    • pp.313-320
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    • 2014
  • The study was conducted to investigate the role of vitamin E in the high altitude hypoxia-induced damage to the intestinal barrier in rats. Sprague-Dawley rats were divided into control (Control), high altitude hypoxia (HH), and high altitude hypoxia + vitamin E (250 mg/kg $BW^*d$) (HV) groups. After the third day, the HH and HV groups were placed in a hypobaric chamber at a stimulated elevation of 7000 m for 5 days. The rats in the HV group were given vitamin E by gavage daily for 8 days. The other rats were given equal volume saline. The results showed that high altitude hypoxia caused the enlargement of heart, liver, lung and kidney, and intestinal villi damage. Supplementation with vitamin E significantly alleviated hypoxia-caused damage to the main organs including intestine, increased the serum superoxide dismutase (SOD) (p< 0.05), diamino oxidase (DAO) (p< 0.01) levels, and decreased the serum levels of interleukin-2 (IL-2) (p< 0.01), interleukin-4 (IL-4) (p<0.001), interferon-gamma ($IFN-{\gamma}$) (p<0.01) and malondialdehyde (MDA) (p<0.001), and decreased the serum erythropoietin (EPO) activity (p<0.05). Administration of vitamin E significantly increased the S-IgA (p<0.001) in ileum and significantly improved the expression levels of occludin and $I{\kappa}B{\alpha}$, and decreased the expression levels of hypoxia-inducible factor 1 alpha and 2 alpha ($HIF-1{\alpha}$ and $HIF-2{\alpha}$), Toll-like receptors (TLR4), P-$I{\kappa}B{\alpha}$ and nuclear factor-${\kappa}B$ p65(NF-${\kappa}B$ P65) in ileum compared to the HH group. This study suggested that vitamin E protectis from intestinal injury caused by high altitude hypoxia environment. These effects may be related to the HIF and TLR4/NF-${\kappa}B$ signaling pathway.

개똥쑥 추출물의 항여드름 효능확인 (Anti-acne Properties of Artemisia annua Extract In Vitro)

  • 유지영;노경백;오세영;정용택;박덕훈;정은선
    • 대한화장품학회지
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    • 제47권3호
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    • pp.247-254
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    • 2021
  • 여드름은 털피지샘단위(pilosebaceous unit)와 관련된 만성 염증 피부 질환으로, 여드름 병변에서는 피지 과다분비(hyperseborrhea)나 이상분비(dysseborrhea), 염증반응, 그리고 다른 피부상재균들에 비해 증가된 Cutibacterium acnes (C. acnes)로 인한 피부 미생물 균총의 불균형이 관찰된다. 이 연구는 개똥쑥 추출물(Artemisia annua extract: AAE)의 항여드름 효과를 확인한 것으로, 피부 미생물 균총의 균형유지와 관련된 항균효과와 염증반응의 억제, 과도한 피지 분비의 감소 측면에서 실험을 진행하였다. C. acnes와 Staphylococcus epidermidis(S. epidermidis)를 AAE와 공동배양 하였을 때, S. epidermidis의 성장률은 저해되지 않았지만 C. acnes의 성장률은 저해된 것을 확인하였다. 또한 AAE를 처리하여 배양한 C. acnes 배양배지를 세포에 처리하였을 때, 인터루킨-1β(IL-1β), 종양괴사인자-α(TNF-α)와 인터루킨-6(IL-6) 같은 사이토카인 분비의 감소와 TLR2 활성 억제도 확인하였다. 마지막으로 피지세포에 AAE를 처리한 결과, 팔미트산에 의해 유도된 피지형성을 감소시키는 것을 확인하였다. 이 결과들은 AAE가 다양한 타깃을 지닌 천연추출물로써 여드름의 주요 원인들인 C. acnes의 선택적 성장저해와 C. acnes로부터 유도되는 염증반응을 억제할 수 있으며, 과도한 피지형성을 감소시켜 결과적으로 여드름을 완화시키는 물질로 사용될 수 있다는 것을 제시한다.