• 제목/요약/키워드: Secretion pathway

검색결과 241건 처리시간 0.022초

The pathophysiology of diabetic foot: a narrative review

  • Jiyoun Kim
    • Journal of Yeungnam Medical Science
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    • 제40권4호
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    • pp.328-334
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    • 2023
  • An aging population and changes in dietary habits have increased the incidence of diabetes, resulting in complications such as diabetic foot ulcers (DFUs). DFUs can lead to serious disabilities, substantial reductions in patient quality of life, and high financial costs for society. By understanding the etiology and pathophysiology of DFUs, their occurrence can be prevented and managed more effectively. The pathophysiology of DFUs involves metabolic dysfunction, diabetic immunopathy, diabetic neuropathy, and angiopathy. The processes by which hyperglycemia causes peripheral nerve damage are related to adenosine triphosphate deficiency, the polyol pathway, oxidative stress, protein kinase C activity, and proinflammatory processes. In the context of hyperglycemia, the suppression of endothelial nitric oxide production leads to microcirculation atherosclerosis, heightened inflammation, and abnormal intimal growth. Diabetic neuropathy involves sensory, motor, and autonomic neuropathies. The interaction between these neuropathies forms a callus that leads to subcutaneous hemorrhage and skin ulcers. Hyperglycemia causes peripheral vascular changes that result in endothelial cell dysfunction and decreased vasodilator secretion, leading to ischemia. The interplay among these four preceding pathophysiological factors fosters the development and progression of infections in individuals with diabetes. Charcot neuroarthropathy is a chronic and progressive degenerative arthropathy characterized by heightened blood flow, increased calcium dissolution, and repeated minor trauma to insensate joints. Directly and comprehensively addressing the pathogenesis of DFUs could pave the way for the development of innovative treatment approaches with the potential to avoid the most serious complications, including major amputations.

Age-related Autoimmune Changes in Lacrimal Glands

  • Rodrigo G. de Souza;Cintia S. de Paiva;Milton R. Alves
    • IMMUNE NETWORK
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    • 제19권1호
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    • pp.3.1-3.17
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    • 2019
  • Aging is a complex process associated with dysregulation of the immune system and low levels of inflammation, often associated with the onset of many pathologies. The lacrimal gland (LG) plays a vital role in the maintenance of ocular physiology and changes related to aging directly affect eye diseases. The dysregulation of the immune system in aging leads to quantitative and qualitative changes in antibodies and cytokines. While there is a gradual decline of the immune system, there is an increase in autoimmunity, with a reciprocal pathway between low levels of inflammation and aging mechanisms. Elderly C57BL/6J mice spontaneously show LGs infiltration that is characterized by Th1 but not Th17 cells. The aging of the LG is related to functional alterations, reduced innervation and decreased secretory activities. Lymphocytic infiltration, destruction, and atrophy of glandular parenchyma, ductal dilatation, and secretion of inflammatory mediators modify the volume and composition of tears. Oxidative stress, the capacity to metabolize and eliminate toxic substances decreased in aging, is also associated with the reduction of LG functionality and the pathogenesis of autoimmune diseases. Although further studies are required for a better understanding of autoimmunity and aging of the LG, we described anatomic and immunology aspects that have been described so far.

The Ralstonia pseudosolanacearum Type III Effector RipL Delays Flowering and Promotes Susceptibility to Pseudomonas syringae in Arabidopsis thaliana

  • Wanhui Kim;Hyelim Jeon;Hyeonjung Lee;Kee Hoon Sohn;Cecile Segonzac
    • Molecules and Cells
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    • 제46권11호
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    • pp.710-724
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    • 2023
  • The plant defense responses to microbial infection are tightly regulated and integrated with the developmental program for optimal resources allocation. Notably, the defense-associated hormone salicylic acid (SA) acts as a promoter of flowering while several plant pathogens actively target the flowering signaling pathway to promote their virulence or dissemination. Ralstonia pseudosolanacearum inject tens of effectors in the host cells that collectively promote bacterial proliferation in plant tissues. Here, we characterized the function of the broadly conserved R. pseudosolanacearum effector RipL, through heterologous expression in Arabidopsis thaliana. RipL-expressing transgenic lines presented a delayed flowering, which correlated with a low expression of flowering regulator genes. Delayed flowering was also observed in Nicotiana benthamiana plants transiently expressing RipL. In parallel, RipL promoted plant susceptibility to virulent strains of Pseudomonas syringae in the effector-expressing lines or when delivered by the type III secretion system. Unexpectedly, SA accumulation and SA-dependent immune signaling were not significantly affected by RipL expression. Rather, the RNA-seq analysis of infected RipL-expressing lines revealed that the overall amplitude of the transcriptional response was dampened, suggesting that RipL could promote plant susceptibility in an SA-independent manner. Further elucidation of the molecular mechanisms underpinning RipL effect on flowering and immunity may reveal novel effector functions in host cells.

Effects of Dyglomera® on leptin expression, pro-inflammatory cytokines, and adipocyte browning in 3T3-L1 cells

  • Da-Eun Min;Sung-Kwon Lee;Hae Jin Lee;Bong-Keun Choi;Dong-Ryung Lee
    • Journal of Applied Biological Chemistry
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    • 제66권
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    • pp.186-196
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    • 2023
  • Dyglomera® is an aqueous ethanol extract derived from the fruit and pods of Dichrostachys glomerata. A previous study has revealed that Dyglomera regulates adipogenesis and lipolysis by modulating AMP-activated protein kinase (AMPK) phosphorylation and increased expression levels of lipolysis-related proteins in white adipose tissue of high fat diet-induced mice and 3T3-L1 adipocyte cells. To further investigate mechanisms of Dyglomera, additional studies were performed using 3T3-L1 cells. Results revealed that Dyglomera downregulated adipogenesis by inhibiting the protein kinase B/mammalian target of rapamycin signaling pathway and reconfirmed that it downregulated gene expression levels of proliferator-activated receptor (PPAR)-γ, CCAAT enhancer binding protein α, sterol-regulation element-binding protein-1c. Dyglomera also reduced adipokines such as tumor necrosis factor alpha, interleukin-1β, and interleukin 6 by regulating leptin expression. Moreover, Dyglomera promoted beige-and-brown adipocyte-related phenotypes and regulated metabolism by increasing mitochondrial number and expression levels of genes such as T-box protein 1, transmembrane protein 26, PR domain 16, and cluster of differentiation 40 as well as thermogenic factors such as uncoupling protein 1, proliferator-activated receptor-gamma co-activator-1α, Sirtuin 1, and PPARα through AMPK activation. Thus, Dyglomera not only can inhibit adipogenesis, but also can promote lipolysis and thermogenesis and regulate metabolism by affecting adipokine secretion from 3T3-L1 adipocytes.

Cigarette Smoke Extract Enhances IL-17A-Induced IL-8 Production via Up-Regulation of IL-17R in Human Bronchial Epithelial Cells

  • Lee, Kyoung-Hee;Lee, Chang-Hoon;Woo, Jisu;Jeong, Jiyeong;Jang, An-Hee;Yoo, Chul-Gyu
    • Molecules and Cells
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    • 제41권4호
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    • pp.282-289
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    • 2018
  • Interleukin-17A (IL-17A) is a pro-inflammatory cytokine mainly derived from T helper 17 cells and is known to be involved in the pathogenesis of chronic obstructive pulmonary disease (COPD). Cigarette smoke (CS) has been considered as a primary risk factor of COPD. However, the interaction between CS and IL-17A and the underlying molecular mechanisms have not been clarified. In the current study, we investigated the effects of cigarette smoke extract (CSE) on IL-17A-induced IL-8 production in human bronchial epithelial cells, and sought to identify the underlying molecular mechanisms. IL-8 production was significantly enhanced following treatment with both IL-17A and CSE, while treatment with either IL-17A or CSE alone caused only a slight increase in IL-8 production. CSE increased the transcription of IL-17RA/RC and surface membrane expression of IL-17R, which was suppressed by an inhibitor of the phosphoinositide 3-kinase (PI3K)/Akt pathway (LY294002). CSE caused inactivation of glycogen synthase $kinase-3{\beta}$ ($GSK-3{\beta}$) via the PI3K/Akt pathway. Blockade of $GSK-3{\beta}$ inactivation by overexpression of constitutively active $GSK-3{\beta}$ (S9A) completely suppressed the CSE-induced up-regulation of IL-17R expression and the CSE-induced enhancement of IL-8 secretion. In conclusion, inactivation of $GSK-3{\beta}$ via the PI3K/Akt pathway mediates CSE-induced up-regulation of IL-17R, which contributes to the enhancement of IL-17A-induced IL-8 production.

Schisandrae Fructus ethanol extract attenuates particulate matter 2.5-induced inflammatory and oxidative responses by blocking the activation of the ROS-dependent NF-κB signaling pathway

  • Lee, Hyesook;Park, Cheol;Kwon, Da Hye;Hwangbo, Hyun;Kim, So Young;Kim, Min Yeong;Ji, Seon Yeong;Kim, Da Hye;Jeong, Jin-Woo;Kim, Gi-Young;Hwang, Hye-Jin;Choi, Yung Hyun
    • Nutrition Research and Practice
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    • 제15권6호
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    • pp.686-702
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    • 2021
  • BACKGROUND/OBJECTIVES: Schisandrae Fructus, the fruit of Schisandra chinensis Baill., has traditionally been used as a medicinal herb for the treatment of various diseases, and has proven its various pharmacological effects, including anti-inflammatory and antioxidant activities. In this study, we investigated the inhibitory effect of Schisandrae Fructus ethanol extract (SF) on inflammatory and oxidative stress in particulate matter 2.5 (PM2.5)-treated RAW 264.7 macrophages. MATERIALS/METHODS: To investigate the anti-inflammatory and antioxidant effects of SF in PM2.5-stimulated RAW 264.7 cells, the levels of pro-inflammatory mediator such as nitric oxide (NO) and prostaglandin E2 (PGE2), cytokines including interleukin (IL)-6 and IL-1β, and reactive oxygen species (ROS) were measured. To elucidate the mechanism underlying the effect of SF, the expression of genes involved in the generation of inflammatory factors was also investigated. We further evaluated the anti-inflammatory and antioxidant efficacy of SF against PM2.5 in the zebrafish model. RESULTS: The results indicated that SF treatment significantly inhibited the PM2.5-induced release of NO and PGE2, which was associated with decreased inducible NO synthase and cyclooxygenase-2 expression. SF also attenuated the PM2.5-induced expression of IL-6 and IL-1β, reducing their extracellular secretion. Moreover, SF suppressed the PM2.5-mediated translocation of nuclear factor-kappa B (NF-κB) from the cytosol into nuclei and the degradation of inhibitor IκB-α, indicating that SF exhibited anti-inflammatory effects by inhibiting the NF-κB signaling pathway. In addition, SF abolished PM2.5-induced generation of ROS, similar to the pretreatment of a ROS scavenger, but not by an inhibitor of NF-κB activity. Furthermore, SF showed strong protective effects against NO and ROS production in PM2.5-treated zebrafish larvae. CONCLUSIONS: Our findings suggest that SF exerts anti-inflammatory and antioxidant effects against PM2.5 through ROS-dependent down-regulating the NF-κB signaling pathway, and that SF can be a potential functional substance to prevent PM2.5-mediated inflammatory and oxidative damage.

Role of ghrelin in the pancreatic exocrine secretion via mitogen-activated protein kinase signaling in rats

  • Lee, Kyung-Hoon;Lee, Jae-Sung;Wang, Tao;Oh, Jin-Ju;Roh, Sanggun;Lee, Hong-Gu
    • Journal of Animal Science and Technology
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    • 제59권7호
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    • pp.16.1-16.6
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    • 2017
  • Background: This study was performed to investigate the impact of exogenous ghrelin on the pancreatic ${\alpha}$-amylase outputs and responses of pancreatic proteins to ghrelin that may relate to pancreatic exocrine. Methods: Sprague-Dawley male rats (9 weeks old, $300{\pm}10g$) were injected with ghrelin via intraperitoneal (i.p.) infusion at dosage of 0, 0.1, 1.0 and $10.0{\mu}g/kg$ body weight (BW), respectively. The plasma ghrelin and cholecystokinin (CCK) level were determined using enzyme immunoassay kit; the mRNA expression of ghrelin receptor ($GHSR-1{\alpha}$) and growth hormone (GH) receptor were assessed by reverse transcription PCR; the expressions of pancreatic ${\alpha}$-amylase activity, extracellular-signal-regulated kinases (ERK), phosphorylated extracellular-signal-regulated kinases (pERK) and c-Jun N-terminal kinase (JNK) were evaluated by western blotting; moreover the responses of pancreatic proteins to ghrelin were analyzed using the two-dimensional gel electrophoresis system. Results: The exogenous ghrelin (1.0 and $10.0{\mu}g/kg\;BW$) elevated the level of plasma ghrelin (p < 0.05), and suppressed the expression of pancreatic ${\alpha}$-amylase at a dose of $10.0{\mu}g/kg\;BW$ (p < 0.05). No difference in the level of plasma CCK was observed, even though rats were exposed to any dose of exogenous ghrelin. In addition, a combination of western blot and proteomic analysis revealed exogenous ghrelin ($10.0{\mu}g/kg\;BW$) induced increasing the JNK and ERK expressions (p < 0.05) and four proteins such as Destrin, Anionic trypsin-1, Trypsinogen, and especially eukaryotic translation initiation factor 3 in rat pancreas. Conclusions: Taken together, exogenous ghrelin by i.p. infusion plays a role in the pancreatic exocrine secretion via mitogen-activated protein kinase signaling pathway.

알레르기 림프구에서 집먼지진드기 알러젠의 PAR2/PKCδ/p38 MAPK 경로를 통한 사이토카인 증가는 호중구의 세포고사를 억제시킨다 (House Dust Mite Allergen Inhibits Constitutive Neutrophil Apoptosis by Cytokine Secretion via PAR2/PKCδ/p38 MAPK Pathway in Allergic Lymphocytes)

  • 이나래;이지숙;김인식
    • 대한임상검사과학회지
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    • 제48권3호
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    • pp.188-195
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    • 2016
  • 본 연구에서는 집먼지 진드기 추출물은 호중구에 단독으로 작용하는 것보다, 림프구와 호중구의 공동배양에서 호중구의 세포고사를 더 억제시켰다. 집먼지 진드기는 알레르기 질환의 림프구에서 IL-6, IL-8, MCP-1, GM-CSF의 분비를 증가시켰다. 집먼지 진드기에 의해 증가된 사이토카인은 protein kinase C ${\delta}$의 억제제인 rottlerin과 p38 MAPK의 억제제인 SB202190에 의해서 감소하였다. 집먼지 진드기에 의해 활성화된 p38 MAPK은 protease-activated receptor (PAR2)의 억제제, rottlerin, SB202190에 의해서 억제되었다. Serine protease 억제제인 aprotinin과 cysteine protease 억제제인 E64은 림프구의 사이토카인의 증가와 관련이 없었다. 또한 집먼지 진드기에 의해 증가된 사이토카인의 변화는 천식과 알레르기 비염 환자에서 차이가 없었다. 림프구에서 집먼지진드기에 의해서 분비되는 분자들은 호중구의 유주운동을 억제시켰다. 본 연구를 통하여 집먼지진드기에 의해 유발되는 알레르기 질환의 병인기전을 규명하는데 유용한 결과가 될 것이다.

Feline adipose tissue-derived mesenchymal stem cells pretreated with IFN-γ enhance immunomodulatory effects through the PGE2 pathway

  • Park, Seol-Gi;An, Ju-Hyun;Li, Qiang;Chae, Hyung-Kyu;Park, Su-Min;Lee, Jeong-Hwa;Ahn, Jin-Ok;Song, Woo-Jin;Youn, Hwa-Young
    • Journal of Veterinary Science
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    • 제22권2호
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    • pp.16.1-16.13
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    • 2021
  • Background: Preconditioning with inflammatory stimuli is used to improve the secretion of anti-inflammatory agents in stem cells from variant species such as mouse, human, and dog. However, there are only few studies on feline stem cells. Objectives: This study aimed to evaluate the immune regulatory capacity of feline adipose tissue-derived (fAT) mesenchymal stem cells (MSCs) pretreated with interferon-gamma (IFN-γ). Methods: To assess the interaction of lymphocytes and macrophages with IFN-γ-pretreated fAT-MSCs, mouse splenocytes and RAW 264.7 cells were cultured with the conditioned media from IFN-γ-pretreated MSCs. Results: Pretreatment with IFN-γ increased the gene expression levels of cyclooxygenase-2, indoleamine 2,3-dioxygenase, hepatocyte growth factor, and transforming growth factor-beta 1 in the MSCs. The conditioned media from IFN-γ-pretreated MSCs increased the expression levels of M2 macrophage markers and regulatory T-cell markers compared to those in the conditioned media from naive MSCs. Further, prostaglandin E2 (PGE2) inhibitor NS-398 attenuated the immunoregulatory potential of MSCs, suggesting that the increased PGE2 levels induced by IFN-γ stimulation is a crucial factor in the immune regulatory capacity of MSCs pretreated with IFN-γ. Conclusions: IFN-γ pretreatment improves the immune regulatory profile of fAT-MSCs mainly via the secretion of PGE2, which induces macrophage polarization and increases regulatory T-cell numbers.

PI3K/Akt 및 MAPK 기전 조절을 통한 Artesunate의 콜라겐 유도의 사람 혈소판 응집 억제효과 (Artesunate inhibits collagen-induced human platelets aggregation through regulation of PI3K/Akt and MAPK pathway)

  • 이동하
    • Journal of Applied Biological Chemistry
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    • 제65권1호
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    • pp.57-62
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    • 2022
  • 혈소판의 과도한 활성화 및 응집은 심혈관계 질환의 주요원인이 된다. 따라서, 혈소판 활성화 및 응집을 억제하는 것은 심혈관계 질환을 예방하고 치료하는데 있어서 매력적인 치료 표적으로 여겨진다. 특히, 혈관 내피세포에서 분비되는 collagen에 의한 강력한 혈소판 활성화와 응집이 혈관질환에서 특징적이다. Artesunate는 Artemisia 또는 Scopolia 속 식물의 뿌리에서 추출한 화합물이며, 항암 및 알츠하이머 병 분야에서 효과가 있다고 보고된 바 있다. 그러나, artesunate가 collagen 유도의 혈소판 활성화와 응집에 미치는 영향과 그 기전에 대해서는 규명된 바가 없다. 본 연구에서는 collagen이 유도하는 사람 혈소판 응집에 있어 artesunate이 미치는 영향을 확인하였고, artesunate의 작용 기전을 명확히 하였다. Artesunate은 혈소판가 활성화 될 때 신호 전달 과정에 작용한다고 알려진 인단백질인 PI3K/Akt 및 MAPK의 인산화를 억제하였다. 또한, artesunate는 TXA2 생성을 감소시켰고, ATP 및 serotonin 방출 등의 혈소판 내 과립 분비를 감소시켰다. 그 결과, artesunate는 혈관 내피세포에서 분비되는 강력한 응집 유도 물질인 collagen으로 유도된 혈소판 응집을 106.41 μM의 IC50로 강력하게 억제하였다. 이 결과들을 통해, artesunate가 혈관 손상을 통해 일어나는 사람 혈소판의 활성화 및 응집을 억제하는 데 유효한 항혈전 물질로 가치가 있음을 제안한다.