Yılın Makalesi Doç. Dr. Hasan Bayram

... konulu sunumlar: "Yılın Makalesi Doç. Dr. Hasan Bayram"— Sunum transkripti:

1 Yılın Makalesi Doç. Dr. Hasan Bayram
Gaziantep Üniversitesi Tıp Fakültesi Göğüs Hastalıkları AD Deneysel Çalışmalar, Solunum Hücre Biyolojisi ve Genetik Çalışma Grubu

2 Kronik Obstrüktif Akciğer Hastalığında
Decreased Histone Deacetylase Activity in Chronic Obstructive Pulmonary Disease Kronik Obstrüktif Akciğer Hastalığında Azalmış Histone Deacetylase Aktivitesi Kazuhiro Ito, Ph.D., Misako Ito, B.A., W. Mark Elliott, Ph.D., Borja Cosio, M.D.,Gaetano Caramori, Ph.D., Onn Min Kon, M.D., Adam Barczyk, M.D.,Shizu Hayashi, Ph.D., Ian M. Adcock, Ph.D., James C. Hogg, M.D., and Peter J. Barnes, D.M., D.Sc. Airway Disease Section, National Heart and Lung Institute, Imperial College, London N Engl J Med 2005;352:

3 Genel Bilgi KOAH, progressif olup, prev artıyor
Sigaraya bağlı hava yolu inflamasyonu Hava akım kısıtlılığı, pulm inflam ilişkili KOAH’ta inflamasyon kompleks IL-8 ve LTB4 gibi kemokinler (nötrofil) TNF- pro-inflamatuar sitokinler KOAH balgamında artmış The global burden of chronic obstructive pulmonary disease (COPD) — a common and debilitating chronic inflammatory disease that is characterized by the progressive development of airflow limitation and is poorly reversible — is increasing. 1 Cigarette smoking is strongly linked with the ongoing inflammation in the airways and lung parenchyma, and the severity of airflow limitation is correlated with the degree of pulmonary inflammation. 2,3 The inflammatory processes in COPD are complex. 4 Neutrophil chemotactic mediators, such as interleukin-8 and leukotriene B , and proinflammatory cytokines, such as tumor necrosis factor a , are increased in the sputum of patients with COPD, as compared with that of normal subjects. 5

4 Nükleozom DNA nukleozomların çevreseini sarmıştır. Nükleozomlar 8 histon molekülünden yapılmış. Histon 2a, 2b, 3,4’den ikişer tane. Her histon molk.nün lizinden zengin uzun bir kuyruğu bulunur, enzim modifikasyonunun yapıldığı kısım Fig. 1. Structure of chromatin. DNA is wound around nucleosomes, which are composed of 8 histone molecules with two copies of histones 2A, 2B, 3 and 4. Each histone molecule has a long tail rich in lysine residues (K), which are the sites of enzymatic modification, such as acetylation, thus changing the charge of the molecule and leading to DNA unwinding The complex of DNA + protein = Chromatin Lizinden zengin kuyruk (asetilasyon vs, DNA sarmalının açılması) İto K,

5 CREB-binding protein (CBP) ve HAT,
Fig. 2. Coactivators, such as CREB-binding protein (CBP) have intrinsic histone acetyltransferase (HAT) activity, resulting in opening up to the chromatin structure, which allows binding of RNA polymerase II and initiation of gene transcription. Several transcription factors interact with CBP, including CREB (cyclic AMP response element binding protein), NF-κB (nuclear factor-κB), AP-1 (activator protein-1) and STATs (signal transduction activated transcription factors). CREB-binding protein (CBP) ve HAT, kromatin açılmasına yol açar, gen transkripsiyonu, Transk fak (AP-1, NF-kB gibi). CBP ile etkileşir İto K,

6 Histon asetilasyonundan sorumlu moleküller
Fig. 3. Molecules responsible for histone acetylation status. Histone acetyltransferase (HAT) acetylates histones, resulting in opening up to the chromatin structure. This is reversed by corepressors, that include histone deacetylases (HDACs) and other associated corepressors which reverse this acetylation, thereby causing gene silencing. Histon asetilasyonundan sorumlu moleküller İto K,

7 Histon deasetilazların (HDAC) sınıflandırılması
Fig. 4. Classification of histone deacetylase. 18 HDACs are identified and classified into 3 or 4 classes. Histon deasetilazların (HDAC) sınıflandırılması İto K,

8 HDAC-Makrofaj HDAC alv. makrofajlarda sitokin üretiminde anahtar molekül HDAC aktivitesinde düşme, KOAH’taki artmış infalamasyonla ilişkili olabilir. We have previously shown that HDAC is a key molecule in the repression of production of proinflammatory cytokines in alveolar macrophages 7Ito K, Barnes PJ, Adcock IM. Glucocorticoid receptor recruitment of histone deacetylase 2 inhibits interleukin-1 betainduced histone H4 acetylation on lysines 8 and 12. Mol Cell Biol 2000;20: ; thus, a decrease in the HDAC could be associated with enhanced inflammation in COPD. 8 The present study was designed to test the hypothesis that the magnitude of the inflammatory response in the peripheral lung that has been described in COPD is associated with a decrease in HDAC activity. 8. Barnes PJ, Ito K, Adcock IM. Corticosteroid resistance in chronic obstructive pulmonary disease: inactivation of histone deacetylase. Lancet 2004;363:731-3. Ito K, et al. Mol Cell Biol 2000; Barnes PJ, et al. Lancet 2004.

9 Hipotez-Amaç “KOAH’ta akciğer periferinde artmış inflamasyon, azalmış HDAC aktivitesine bağlıdır.” Hipotezini test etmek. The present study was designed to test the hypothesis that the magnitude of the inflammatory response in the peripheral lung that has been described in COPD is associated with a decrease in HDAC activity.

10 Materyal ve Metod

11 Doku Bankasından Periferik AC Spesmeni
IL-8 mRNA ve IL-8 promoter’da Histon 4 asetilasyonuna HDAC aktivitesi HAT aktivitesi HDAC aktivitesi ile KOAH FEV1 arasındaki korelasyon HDAC protein ekspresyonu Hasta spesmeni: Doku bankasından Non-smoker: 11 (normal AC Figure 1. Interleukin-8 Gene Expression and Histone Deacetylase (HDAC) in Peripheral Lung Tissue from Patients with COPD. Panel A shows interleukin-8 messenger RNA (mRNA) expression and histone-4 acetylation at the interleukin-8 promoter. Panel B shows HDAC activity. Panel C shows histone acetyltransferase (HAT) activity. The data were plotted as means ±SE, with the number of subjects in each group ranging from 5 to 11. (The complete data are given in Supplements 1, 2, and 3 of the Supplementary Appendix.) Panel D shows the correlations between HDAC activity and the ratio of forced expiratory volume in one second (FEV 1 ) to forced vital capacity (FVC) in specimens obtained from normal nonsmokers and from patients with COPD at different stages. The dotted line indicates the 95 percent confidence interval of the regression line. When the single outlier point shown at the top right in this panel was omitted, there was still a significant positive correlation between HDAC activity and FEV :FVC (r=0.60, P<0.001). S0, S1, S2, and S4 denote severity of disease according to the grading of the Global Initiative for Obstructive Lung Disease, with higher numbers indicating greater severity; PN pneumonia; and CF cystic fibrosis. We obtained specimens of lung tissue and data on patients’ lung function from a tissue bank that was linked to an established patient registry. 10 Specimens of peripheral lung tissue were obtained from 11 patients who were nonsmokers without symptoms who had normal lung function and from 29 patients who were smokers: 9 with stage 0 COPD, 10 with stage 1 COPD, and 10 with stage 2 COPD. Specimens of peripheral lung tissue were obtained from an additional six patients with stage 4 COPD who were undergoing lung-volume–reduction surgery. The patient registry and the tissue bank also provided specimens of peripheral lung tissue from five patients who had a tumor that had produced obstructive pneumonia, as well as from five explanted lungs of patients with cystic fibrosis. Baseline characteristics of the patients are summarized in Table 1.

12 (Periferik AC Dokusu) Hasta spesmeni: Doku bankasından
Non-smoker: 11 (normal AC fonksiyonları) KOAH: Evre 0,1,2, Evre 4: Lung reduction cerrahisine gidenlerden Pnömoni: Malignite nedeniyle pnömoni gelişenlerden, Kistik fibrozis: 5 hastanın akciğer explantından. We obtained specimens of lung tissue and data on patients’ lung function from a tissue bank that was linked to an established patient registry. 10 Specimens of peripheral lung tissue were obtained from 11 patients who were nonsmokers without symptoms who had normal lung function and from 29 patients who were smokers: 9 with stage 0 COPD, 10 with stage 1 COPD, and 10 with stage 2 COPD. Specimens of peripheral lung tissue were obtained from an additional six patients with stage 4 COPD who were undergoing lung-volume–reduction surgery. The patient registry and the tissue bank also provided specimens of peripheral lung tissue from five patients who had a tumor that had produced obstructive pneumonia, as well as from five explanted lungs of patients with cystic fibrosis. Baseline characteristics of the patients are summarized in Table 1.

13 Alveolar Makrofajlar (KOAH) Bronş Biyopsileri (KOAH- Hafif Astım)
HAT HDAC aktivitesi HDAC mRNA ekspresyonu (makrofaj)

14 Alveolar makrofajlar, BAL ile alınmış
Alveolar makrofajlar, BAL ile alınmış. Normal ve sigara içen ile Evre 2 veya 3 KOAH’lıdan. Alveolar macrophages were obtained by bronchoalveolar lavage from six healthy nonsmokers, six healthy current smokers, and seven patients with stage 2 or 3 COPD (Table 2). Bronchial-biopsy specimens were collected from 14 normal subjects who were nonsmokers, 10 patients with mild asthma and 13 age-matched subjects who were smokers, and 7 patients with COPD (stage 2 or 3) and 10 agematched smokers (Table 2). Normal healthy subjects for bronchoscopy studies were volunteers recruited through advertisement. Although these samples were not specifically collected for this study, our study was part of a project that examined the molecular mechanism of inflammation in COPD, and it was approved by the local research ethics committees. All subjects had provided written informed consent for the deposition of their tissues in the tissue bank from which we obtained the specimens and for their use in research studies of this type.

15 Table 2. Characteristics of Subjects Underwent Bronchial Biopsy.*
Bronş biyopsileri 14 normal sigara içmeyen, hafif astımlı 10, sigara içen astımlı gruba yaşı uygun-13 kişi. 7 KOAH’lı, 10 yaşı uygun smoker. Bronchial-biopsy specimens were collected from 14 normal subjects who were nonsmokers, 10 patients with mild asthma and 13 age-matched subjects who were smokers, and 7 patients with COPD (stage 2 or 3) and 10 agematched smokers (Table 2). Normal healthy subjects for bronchoscopy studies were volunteers recruited through advertisement. Although these samples were not specifically collected for this study, our study was part of a project that examined the molecular mechanism of inflammation in COPD, and it was approved by the local research ethics committees. All subjects had provided written informed consent for the deposition of their tissues in the tissue bank from which we obtained the specimens and for their use in research studies of this type.

16 İstatiksel Analiz Varyans analizi non-parametrik Kruskal-Wallis ile
Anlamlı olduğunda, Mann-Whitney U ile gruplar karşılaştırılmış. Korelasyon Sperman’s rank metodu ile İki yönlü p<0.05 anlamlı bulunmuş. statistical analysis Results are expressed as means ±SE. Other measures (medians and standard deviations) are provided in the Supplementary Appendix. Analysis of variance was performed with the use of the nonparametric Kruskal–Wallis test. When the result was significant, the Mann–Whitney U test was performed for comparisons between groups (SPSS software). Correlation coefficients were calculated with the use of Spearman’s rank method. A P value of less than 0.05 was considered to indicate statistical significance. All reported P values are two-sided.

17 Sonuçlar

18 Peripheral Lung Tissue from Patients with COPD
Periferik AC dokusunda (doku bankası) alınan dokuda solda IL-8 mRNA ekspresyonu ve IL-8 promoter bölgesinde histon asetilasyonunu VS Non-smokers. Sağdaki grafik aynı dokuda HDAC aktivitesini gösteriyor. Promoter: DNA’da RNA polimerazın bağlanıp transkripsiyonun başlayacağı bölge. Figure 1. Interleukin-8 Gene Expression and Histone Deacetylase (HDAC) in Peripheral Lung Tissue from Patients with COPD. Panel A shows interleukin-8 messenger RNA (mRNA) expression and histone-4 acetylation at the interleukin-8 promoter. Panel B shows HDAC activity.) to forced vital capacity (FVC) in specimens obtained from normal nonsmokers and from patients with COPD at different stages. The dotted line indicates the 95 percent confidence interval of the regression line. When the single outlier point shown at the top right in this panel was omitted, there was still a significant positive correlation between HDAC activity and FEV 1 :FVC (r=0.60, P<0.001). S0, S1, S2, and S4 denote severity of disease according to the grading of the Global Initiative for Obstructive Lung Disease, with higher numbers indicating greater severity; PN pneumonia; and CF cystic fibrosis. *IL-8 mRNA ve IL-8 promoter’da Histon 4 asetilasyonu *Hastalığın şiddeti ile pozitif korelasyon HDAC aktivitesi

19 Peripheral Lung Tissue from Patients with COPD
Solda, periferik AC dokusunda Histon asetil transferaz aktivitesi görülüyor. Anlamlı bir fark yok. Sağdaki grafikte HDAC aktivitesi ile KOAH’ta % FEV1/FVC arasındaki korelasyon görülüyor. FEV1 ile HDAC aktivitesi arasında pozitif korelasyon görünüyor. Panel C shows histone acetyltransferase (HAT) activity. The data were plotted as means ±SE, with the number of subjects in each group ranging from 5 to 11. (The complete data are given in Supplements 1, 2, and 3 of the Supplementary Appendix.) Panel D shows the correlations between HDAC activity and the ratio of forced expiratory volume in one second (FEV 1 ) to forced vital capacity (FVC) in specimens obtained from normal nonsmokers and from patients with COPD at different stages. The dotted line indicates the 95 percent confidence interval of the regression line. When the single outlier point shown at the top right in this panel was omitted, there was still a significant positive correlation between HDAC activity and FEV :FVC (r=0.60, P<0.001). S0, S1, S2, and S4 denote severity of disease according to the grading of the Global Initiative for Obstructive Lung Disease, with higher numbers indicating greater severity; PN pneumonia; and CF cystic fibrosis. HAT aktivitesi ve KOAH HDAC aktivitesi ve %FEV1/FVC

20 KOAH’ta Periferik AC dokusunda Histone
Deacetylase (HDAC) Gen Ekspresyonu Figure 2. Histone Deacetylase (HDAC) Expression in Peripheral Lung Tissue. Panel A shows the expression of histone deacetylase (HD) genes 1 through 8 with the use of real-time PCR. In Panel A, there were significant differences (asterisks indicate P<0.05 and daggers P<0.01 for the comparison with nonsmokers, and double daggers P<0.05 and section marks P<0.01 for the comparison with patients with COPD stage 0) HDAC 1-8 gen ekspresyonu, ‘real time’ PCR (* VS non-smoker ve sO.)

21 KOAH’ta Periferik AC dokusunda Histone
Deacetylase (HDAC) Protein Ekspresyonu Bu grafikte WB aracılığıyla, periferik AC dokusundaki HDAC2 ekspresyonunu görüyorsunuz. Sağdaki grafik soldaki WB görüntülerinin dansitometrik analizinden hazırlanmış. VS Non smokers Panel B shows HDAC2 protein expression with the use of Western blotting and lamin A and lamin C (lamin A/C) nuclear membrane proteins as an internal control for nuclear-protein loading. Panel C shows the densitometric analysis of HDAC2 protein expression in samples of peripheral lung tissue from healthy nonsmokers (NS) and from patients with COPD stage 0 (S0), stage 1 (S1), stage 2 (S2), and stage 4 (S4).

22 Alveolar Makrofajlar HDAC ve HAT aktivitesi HDAC mRNA ekspresyonu
Soldaki grafide Non-smoker, smoker ve KOAH’lıların makrofajlarındaki HDAC ve HAT aktivitesi görülüyor. Gördüğünüz gibi KOAH’lılarda HDAC aktivitesi anlamlı olarak azalmış. Sağdaki grafikde HDAC mRNA ekspresyonu görülüyor. Panel A shows HDAC activity and HAT activity. Panel B shows expression of HDAC (HD) 1 through 8 mRNA in alveolar macrophages. VS Non-smokers Figure 3. Histone Deacetylase (HDAC) and Histone Acetyltransferase (HAT) Activity in Alveolar Macrophages and Bronchial-Biopsy Specimens. Panel A shows HDAC activity and HAT activity. Panel B shows expression of HDAC (HD) 1 through 8 mRNA in alveolar macrophages. HDAC ve HAT aktivitesi HDAC mRNA ekspresyonu

23 Bronş Biyopsileri HDAC Aktivitesi HAT Aktivitesi
Bu durum sadece KOAH’a mı özgü? Yoksa hava yollarında obstrüksiyonla mı ilişkili? Astımda durum ne? Bronş biyopsilerindeki HDAC ve HAT aktivitesini görüyorsunuz. Grup 1 kontrol (astım için?, daha genç) Grup 2 (KOAH için?, daha yaşlı)’ye göre daha genç. Hastalar steroid almamışlardır. VS Non-smokers, solda COPD vs Grup 2 smoker. Figure 3. Histone Deacetylase (HDAC) and Histone Acetyltransferase (HAT) Activity Bronchial-Biopsy Specimens. Panel C shows HDAC activity. Panel D shows HAT activity in bronchial-biopsy specimens obtained from healthy nonsmokers, healthy smokers (those in group 1 are younger than those in group 2), and patients with COPD and those with mild asthma that had not previously been treated with steroids. The results are plotted as means ±SE, with the number of subjects in each group ranging from 6 to 14. In Panels A, C, and D, P values for the comparison with nonsmokers are shown above each bar. In Panel B, the significant differences are shown by the symbols above the bars (the asterisk indicates P<0.05 and the daggers P<0.01 for the comparison with nonsmokers). ( HDAC Aktivitesi HAT Aktivitesi

24 Sonuçlar: Periferik AC Dokusunda
IL-8 mRNA ve IL-8 promoter’da Histon 4 asetilasyonu Evre 2, 3 KOAH’da  HAT aktivitesi  HDAC aktivitesi  HDAC aktivitesi ile KOAH’ta FEV1, %FEV1/FVC arasında + korelasyon HDAC ekspresyonu Evre 4 KOAH’ta Evre 0 KOAH ve ‘non-smoker’ lara göre 

25 Sonuçlar: Alveolar Makrof (KOAH)
HDAC aktivitesi  HAT aktivitesi  HDAC mRNA ekspresyonu 

26 Sonuçlar: Bronş Biyopsileri (KOAH - Hafif Astım)
HAT aktivitesi KOAH’ta  Astımda  HDAC aktivitesi KOAH’ta  Astımda

27 Tartışma-1 HAT/HDAC aktivasyonundaki denge periferik AC dokusunda histon hiperasetilasyonundaki artışa kayıyor Bu KOAH’a spesifik olabilir (Astım, kistik fibrozis, pnömonide bu gözlenmemiş) Astımda HAT aktivitesindeki artış önceki bulgularıyla korele* There was a positive correlation between histone-4 acetylation and HDAC activity (P<0.001), indicating that the balance between HAT activity and HDAC activity is shifted toward histone hyperacetylation in the peripheral lung of patients with COPD. These changes may be relatively specific to COPD, because we could not find a reduction in total HDAC activity in samples from patients with asthma, cystic fibrosis, or pneumonia (Fig. 1 and 3). In contrast, in asthma, which also involves increased expression of inflammatory genes in the respiratory tract, we confirmed previous observations 14 showing increased HAT activity in bronchial-biopsy specimens. *Ito K, et al. Am J Respir Crit Care Med 2002.

28 Tartışma-2 Astım (HAT ) ve KOAH’ta (HDAC ) kromatin, farklı mekanizmalarla hiperasetile oluyor Bu kromatinin açılmasına, ve inflamatuar gen ekspresyonunda artışa yol açıyor In contrast, in asthma, which also involves increased expression of inflammatory genes in the respiratory tract, we confirmed previous observations 14 showing increased HAT activity in bronchial-biopsy specimens. Thus, in both asthma and COPD, chromatin appears to be hyperacetylated but by means of different mechanisms, and this increased histone acetylation provides a mechanism for local unwinding of chromatin and a subsequent increase in inflammatory gene expression. 6 This finding suggests that the clinical stage of COPD may be related to reduced HDAC activity, and this reduced activity, in turn, could facilitate increased expression of the relevant inflammatory genes.

29 Tartışma-3 Histon asetilasyonunu regule eden 11 HDAC var
HDAC2 inflamatuar gen ekspresyonunun düzenlenmesinde etkili HDAC3, 5, ve 8 hücre siklüsü, diferansiasyonu ve apoptozisinde etkili* HDAC3, 5, 8 KOAH , mekanizmalar? There are 11 classic human HDACs that regulate histone acetylation. 15 We previously reported that HDAC2 is involved in suppression of NFk B– mediated inflammatory gene expression by corticosteroids. 7 In the present study, we have shown that HDAC2 mRNA and protein expression is significantly reduced in tissue specimens of the peripheral lung and in alveolar macrophages from patients with COPD. HDAC3, 5, and 8 are also reduced in lung tissue and macrophages. These HDAC isoforms are reported to be involved in the cell cycle, cell differentiation, and apoptosis. Further experiments will be required to clarify how the reduced function of these HDACs influences the inflammatory process in COPD. de Ruijter AJ, van Gennip AH, Caron HN, Kemp S, van Kuilenburg AB. Histone deacetylases (HDACs): characterization of the classical HDAC family. Biochem J 2003; 370: 16. Durst KL, Lutterbach B, Kummalue T, Friedman AD, Hiebert SW. The inv(16) fusion protein associates with corepressors via a smooth muscle myosin heavy-chain domain. Mol Cell Biol 2003;23: 17. Bertos NR, Wang AH, Yang XJ. Class II histone deacetylases: structure, function, and regulation. Biochem Cell Biol 2001;79: *de Ruijter AJ, Biochem J 2003; Bertos NR, Biochem Cell Biol 2001

30 Tartışma-4 Düşen HDAC aktivitesi reversible olabilir
Teofilin HDAC aktivatörü (Ito K, 2002) Düşük teofilin alv macroph azalmış HDAC aktivitesini düzeltmiş, inf sitokin salınımını, steroid cevabını restore* Bu etkinin kliniğe yansıması?? We speculate that our findings may have therapeutic implications, because reductions in HDAC activity may be reversible. Theophylline is an activator of HDAC, 13 and we have recently shown that low concentrations of theophylline completely restore HDAC activity in alveolar macrophages from patients with COPD, with reduced production of inflammatory cytokines and restoration of responsiveness to corticosteroids. 18 Whether this is a mechanism of the therapeutic action of theophylline in COPD is not known. We report that total HDAC activity and the expression of specific HDAC isoenzymes are decreased in peripheral lung tissue, bronchial-biopsy specimens, and alveolar macrophages of patients with COPD and that this finding is related to increasing disease severity. This finding could in part account for the increased inflammatory response in the respiratory tract of patients with COPD. *Cosio BG, J Exp Med 2004.

31 Yorum - Artılar KOAH’taki inflamasyonun anlaşılmasında farklı bir boyut, yeni bir teori In vivo ve in vitro ayağı çok iyi kombine eden bir çalışma KOAH’ta tedaviye farklı bir boyut getirebilecek veriler Başarıya ulaşırsa NOBEL!?

32 Yorum - Eksiler Periferik doku, doku bankası yerine prospektif olarak alınsa daha iyi olurdu Biyopsi ve BAL (makrofaj için) çalışmasında Evre 2-3 KOAH kombine edilmiş

33 EDITORIAL COPD Unwound Steven D. Shapiro, M.D.
N Engl J Med 2005;352:

34 ve Histon asetilasyonu
KOAH’ta İnflamatuar hücre İnteraksiyonu ve Histon asetilasyonu Figure 1. Inflammatory-Cell Interactions in Chronic Obstructive Pulmonary Disease (COPD) and the Role of Histone Acetylation. Reactive oxygen species resulting from inhaled cigarette smoke (and potentially from the inflammatory cells themselves) promote transcription of nuclear factorkB (NFkB)–mediated proinflammatory factors by way of two mechanisms. First, oxidation results in the degradation of IKkB, releasing NFk B, which then translocates to the nucleus of the targeted cell. Oxidation also inactivates histone deacetylase (HDAC), shifting the balance to increased DNA acetylation, weakening the interactions between histone and DNA and “unwinding” DNA, allowing NFk B greater access to the DNA promoter elements, and leading to transcription of neutrophil chemokines and cytokines (tumor necrosis factora [TNFa ] and interleukin-8) and matrix metalloproteinases (MMPs). These factors recruit and activate neutrophils to the lung. In addition, CD8+ T cells augment the production of macrophage MMPs through interactions with surface-bound CD40 molecules and interferon-inducible chemokines (inducible protein of 10 kD [IP-10], interferon-inducible T-cell alpha chemoattractant [I-TAC], and monokine induced by interferong [MIG]). Macrophage MMPs and neutrophil elastase degrade each other’s inhibitors, the tissue inhibitor of metalloproteinases and alpha1-antitrypsin, respectively, augmenting their matrix-degrading capacities. These interactions illustrate the highly interactive nature of the immune inflammatory response and suggest that breaking this cycle, perhaps by way of augmentation of HDAC with the use of theophylline, may prevent inflammatory-mediated destruction of the lung in COPD. Dashed lines indicate inhibition.

35 Editorial-1 KOAH’ta sorun, doku destrüksiyonuna yol açan inflamatuar hücre ve mediatörler arasındaki etkileşimi modifiye etmek, bu kısır döngüyü kırmak. Sigara inflamasyonu başlatıyor, ancak bıraktıktan sonra da devam ediyor. Olay sanıldığından karmaşık The challenge now is to understand the interplay between different immune and inflammatory cells and the mediators they produce that lead to tissue destruction. If we can do this, then we may be able to find safe and effective means to inhibit this destructive cascade and prevent disease progression. If only it were so simple; the data suggest the presence of a moving inflammatory target. Cigarette smoke initiates inflammation, in part by way of the oxidation effects discussed above, yet in severe COPD, other factors appear to sustain inflammation long after smoking cessation. This difference was best shown in a study that examined the lung tissue of patients with end-stage COPD who had not smoked a cigarette in more than nine years (on average). 5 Rather than being “burned out,” as expected, the lungs were filled with a variety of inflammatory cells. Whether the inflammation is related to bacterial colonization, latent viral infection, residual matrix fragments, or other mechanisms is not clear. What is clear is that after a certain threshold of disease severity is passed, simply quitting smoking may not be sufficient to prevent disease progression.

36 Editorial-2 Sigara KOAH’ta önemli risk faktörü, ancak ¼ kişide gelişiyor Astım diğer bir inflamatuar hastalık Acaba KOAH ve astım aynı patolojinin farklı fenotipleri mi ? (‘Dutch’ Hipotezi) İkisi farklı patolojiler? (‘İngiliz Hipotezi’) Astımda steroid etkili (steroid reseptörü HDAC’a bağlanıp, etki için onu nükleusa transloke ediyor) Asthma is another common inflammatory lung disease. The similarities and differences between asthma and COPD engendered a feud between the Dutch and the British that has raged for nearly half a century. The difference in the response to corticosteroids in patients with asthma and in those with COPD in relation to HDAC signaling has worked its way into this debate. The controversy centers on an explanation of the observation that even though cigarette smoking is the overwhelming risk factor for COPD, the disease develops in only a minority of smokers. In 1961, Orie and colleagues advanced the hypothesis that the obstructive airway diseases, including asthma, chronic bronchitis, and emphysema, represent different phenotypes of a common pathogenetic process. 6 This theory was later labeled the Dutch hypothesis and has evolved into the concept that asthma and COPD have common origins. The British proposed a competing theory that stated that smokers with chronic production of sputum were the ones at increased risk for the development of COPD. Epidemiologic studies have not supported the British hypothesis. However, this does not mean that there is universal acceptance of the Dutch hypothesis. In fact, at the 2003 meeting of the American Thoracic Society, one of the authors, Dr. Barnes, claimed in discussion that “the Dutch were confused. Some patients with COPD also have asthma.” Arguing against the Dutch hypothesis, Dr. Barnes could point to the fact that corticosteroids are much more effective in asthma than in COPD. The reason for this difference is that in asthma corticosteroids stimulate the glucocorticoid receptor that binds HDAC and translocates it to the nucleus for action,

37 Editorial-3 KOAH’ta oksidanlara bağlı HDAC, steroid cevabı yok
Sigara içen astımlılarda steroide cevap azalmalı, Çalışmalar bu konsepti destekliyor.* NHLBI, geniş prospektif bir çalışmayı bitirmek üzere (sigara-astımda steroid) Daha çok çalışmaya ihtiyaç var whereas in COPD oxidant-modified HDAC will not interact with the glucocorticoid receptor. This theory would also predict that corticosteroids are less effective in patients with asthma who smoke. Indeed, two small prospective studies confirmed that patients with stable asthma who smoked had an impaired response to either inhaled or oral corticosteroids. 7 The National Heart, Lung, and Blood Institute’s Asthma Clinical Research Network has almost completed a larger prospective randomized trial based on this issue (Smoking Modulates Outcomes of Glucocorticoid Therapy in Asthma). *Chaudhuri R,et al. Am J Respir Crit Care Med 2003.

38 Editorial-4 Yeni çalışmalar!!! Astım ve KOAH tek hastalık gibi değil
Etkileşim var, bir birlerini ağırlaştırabilirler (KOAH, steroid dirençli astım) KOAH ciddi sorun HDAC teorisi çalışırsa, Teofilin ve steroid kombinasyonu KOAH’ta önemli iş görebilir Yeni çalışmalar!!! Although, admittedly, asthma and COPD are unlikely to represent a single disease, they probably share pathogenetic mechanisms that interact, each making the other disease process worse. These interactions may become important as we search for effective therapy for steroid-resistant asthma and COPD. COPD is now epidemic worldwide, and we have few effective therapies to offer patients as they slowly suffocate. But the HDAC theory may be more than molecular medicine for its own sake. A potential practical implication of the theory derives from the observation that low-dose theophylline markedly induces HDAC transcription. If true, then the combination of corticosteroids and theophylline should restore delivery of HDAC to the nucleus and disarm inflammation in COPD. 8 I look forward to a future study showing that the combination of these two well-known drugs inhibits disease progression in patients with COPD.

39 Sabrınız için teşekkürler

40 Çeşitli Durumlarda HDAC Aktivitesi

41 Sigara içicilerinin makrofajlarında HDAC2 
Ito K, 2006,

42 KOAH’ta Steroid Direnci Mekanizmaları
Fig. 13. Proposed mechanism of amplified inflammation and corticosteroid resistance in COPD patients. Stimulation of normal alveolar macrophages activates nuclear factor- k B (NF-κB) and other transcription factors to switch on histone acetyltransferase leading to histone acetylation and subsequently to transcription of genes encoding inflammatory proteins, such as tumor necrosis factor-α (TNF-α), interleukin-8 (IL-8) and matrix metalloproteinase-9 (MMP-9). HDAC2 itself reverses histone acetylation, or corticosteroids reverse this by binding to glucocorticoid receptors (GR) and recruiting histone deacetylase-2 (HDAC2). This reverses the histone acetylation induced by NF-κB and switches off the activated inflammatory genes. In COPD patients cigarette smoke activates macrophages, as in normal subjects, but oxidative stress (acting through the formation of peroxynitrite) impairs the activity of HDAC2. This amplifies the inflammatory response to NF-κB activation, but also reduces the antiinflammatory effect of corticosteroids as HDAC2 is now unable to reverse histone acetylation. Ito K, 2006,

43 Teofilin ağır sigara içicilerinin ve KOAH’lıların
Makrofajlarında azalan HDAC aktivitesini düzeltiyor Fig. 12. Effect of theophylline on HDAC activity reduced in heavy smokers and patients with COPD. Alveolar macrophages were obtained from heavy smokers and patients with COPD. Theophylline at 10-6 M or 10-5 M was added to nuclear extracts from each patient and HDAC activity was determined with commercial kit. (Adapted from Cosio, B.G. et al. J Exp Med 2004, 200: by copyright permission of The Rockefeller University Press. JEM Online,

44 Teşekkürler Claude Monet, Waterloo Bridge, London, 1903
Monet’in tablosunda görüldüğü gibi hava kirliliği 19.yy başlarında başta Endüstrileşmiş ülkelerde ortaya çıkmış ve sağlığı ciddi şekilde tehdit etmiştir. Bir yandan da neden olduğu farklı ışık yansımaları ile Monet gibi sanatçılara esin kaynağı olmuştur. Ancak bu gün Londra’da Waterloo köprüsünün yanında dururken artık bu manzarayı görmüyorsunuz. Bu manzara ne yazıkki FIG 1. Claude Monet, Waterloo Bridge, This is one of a total of 36 paintings he made of this subject, illustrating the interplay between changing light conditions and the air pollutants derived from open coal burning. This example hangs in the Hermitage Museum in St Petersburg and was photographed by the author. Claude Monet, Waterloo Bridge, Effect of Fog, reproduced by permission of The State Hermitage Museum, St Petersburg, Russia. J ALLERGY CLIN IMMUNOL FEB 2005 Teşekkürler Claude Monet, Waterloo Bridge, London, 1903

45 Teofilinin KOAH’ta etkileir
ZuWallack RL, et al. Salmeterol plus theophylline combination therapy in the constriction in asthma: antagonism by inhaled theophylline. Am Rev Respir Dis 1984;129:380–384. treatment of COPD. Chest 2001;119:1661–1670. Kirsten DK, et al. Effects of theophylline withdrawal in severe chronic obstructive pulmonary disease. Chest 1993;104:1101–1107. Chrystyn H, et al. Dose response relation to oral theophylline in severe chronic obstructive airway disease. BMJ 1988; 297:1506–1510. 18. ZuWallack RL, Mahler DA, Reilly D, Church N, Emmett A, Rickard K, Knobil K. Salmeterol plus theophylline combination therapy in the constriction in asthma: antagonism by inhaled theophylline. Am Rev Respir Dis 1984;129:380–384. treatment of COPD. Chest 2001;119:1661–1670. 19. Kirsten DK, Wegner RE, Jorres RA, Magnussen H. Effects of theophylline withdrawal in severe chronic obstructive pulmonary disease. Chest 1993;104:1101–1107. 20. Chrystyn H, Mulley BA, Peake MD. Dose response relation to oral theophylline in severe chronic obstructive airway disease. BMJ 1988; 297:1506–1510.

46 KOAH’ta steroid direnci
Fig. 11. Possible mechanism of reduction in histone deacetylase 2 (HDAC2). HDAC2 is inactivated by peroxynitrite, generated by an interaction of nitric oxide (NO) generated by NO synthase (NOS) and cigarette smoke and superoxide anions (·O2-). Peroxynitrite nitrates tyrosine (Tyr) residues on HDAC2 and this may block enzymatic activity and also mark the enzyme for ubiquitination (Ub) and destruction by the proteasome. The loss of HDAC2 leads to amplification of the inflammatory response and resistance to corticosteroids. Ito K, 2006,

47 Histon Asetil Transferaz- Histon Deasetilaz
Nükleer enzimler Kromatin yapısını regüle ederek inflamatuar gen ekspresyonunu modifiye ederler Histone acetyltransferase (HAT) and histone deacetylase (HDAC) are families of nuclear enzymes that modify the expression of inflammatory genes by regulating chromatin structure.

48 Histon Asetilasyonu Transkripsiyon ko-aktivatör proteinler histon asetil transferaz aktivitesi gösterirler Kromatin yapısını değiştirir Transkripsiyon faktörleri ve RNA polimeraz II’nin DNA bağlanmsına izin verir Gen transkripsiyonunu artırır Kor histonların deasetilasyonu gen transkripsiyonu baskılar Acetylation of the core histones by transcriptional coactivator proteins, which possess intrinsic HAT activity, leads to changes in the chromatin structure that subsequently allow the transcription factors and RNA polymerase II to bind to DNA and enhance gene transcription. Conversely, deacetylation of the core histones is generally associated with the repression of transcription.