Subpleural fibrotic interstitial lung abnormalities are implicated in non-small cell lung cancer radiotherapy outcomes.

BACKGROUND: The relationship between interstitial lung abnormalities (ILAs) and the outcomes of lung cancer radiotherapy is unclear. This study investigated whether specific ILA subtypes are risk factors for radiation pneumonitis (RP). PATIENTS AND METHODS: This retrospective study analysed patients with non-small cell lung cancer treated with radical-intent or salvage radiotherapy. Patients were categorised into normal (no abnormalities), ILA, and interstitial lung disease (ILD) groups. The ILA group was further subclassified into non-subpleural (NS), subpleural non-fibrotic (SNF), and subpleural fibrotic (SF) types. The Kaplan-Meier and Cox regression methods were used to determine RP and survival rates and compare these outcomes between groups, respectively. RESULTS: Overall, 175 patients (normal, n = 105; ILA-NS, n = 5; ILA-SNF, n = 28; ILA-SF, n = 31; ILD, n = 6) were enrolled. Grade ≥2 RP was observed in 71 (41%) patients. ILAs (hazard ratio [HR]: 2.33, p = 0.008), intensity-modulated radiotherapy (HR: 0.38, p = 0.03), and lung volume receiving 20 Gy (HR: 54.8, p = 0.03) contributed to the cumulative incidence of RP. Eight patients with grade 5 RP were in the ILA group, seven of whom had ILA-SF. Among radically treated patients, the ILA group had worse 2-year overall survival (OS) than the normal group (35.3% vs 54.6%, p = 0.005). Multivariate analysis revealed that the ILA-SF group contributed to poor OS (HR: 3.07, p =0.02). CONCLUSIONS: ILAs, particularly ILA-SF, may be important risk factors for RP, which can worsen prognosis. These findings may aid in making decisions regarding radiotherapy.

Stereotactic body radiation therapy for prostate cancer: a study comparing 3-year genitourinary toxicity between CyberKnife and volumetric-modulated arc therapy by propensity score analysis.

BACKGROUND: To investigate whether the rate of stereotactic body radiation therapy-related (SBRT-related) genitourinary (GU) toxicity is lower in patients with prostate cancer treated with CyberKnife. METHODS: We retrospectively reviewed the medical records of patients with nonmetastatic prostate cancer at two institutions between 2017 and 2020. We analyzed 70 patients who were extracted by propensity score matching based on age, pre-treatment International Prostate Symptom Score (IPSS), and prostate volume. The patients were treated with SBRT, with a total dose of 36.25 Gy in five fractions over five consecutive weekdays, using CyberKnife or volumetric-modulated arc therapy (VMAT). RESULTS: The low-, medium-, and high-risk patients were 2, 19, and 14, respectively, in the CyberKnife group and 4, 17, and 14, respectively, in the VMAT group. The median follow-up time in both groups was 3 years. One patient with CyberKnife died of unrelated causes. No biochemical or clinical recurrence, distant metastases, or death from prostate cancer was observed. The peak values of IPSS in the acute phase (< 3 months) were significantly lower in the CyberKnife than in the VMAT group (CyberKnife:16.2 vs VMAT:20.2, p = 0.025). In multiple regression analyses, the treatment modality (p = 0.03), age (p = 0.01), bladder medication pre-irradiation (p = 0.03), and neoadjuvant androgen deprivation therapy (p = 0.04) contributed to the peak value of the acute-phase IPSS. The incidence of treatment-related grade 2 acute GU toxicity tended to be lower in the CyberKnife than the VMAT group (CyberKnife: 22.9% vs. VMAT: 45.7%, p = 0.077). No difference was noted between the groups with regard to late IPSS or GU toxicity and gastrointestinal toxicity in all phases. Toxicities of grade ≥ 3 have not been observed to date. CONCLUSIONS: Regardless of treatment modality, SBRT is effective in treating prostate cancer without serious toxicity. However, CyberKnife has an advantage over VMAT in terms of acute prostate symptoms.

Automatic one-click planning for hippocampal-avoidance whole-brain irradiation in RayStation.

This study aimed to verify the accuracy of auto-contouring and auto-dose optimization for hippocampal-avoidance whole-brain radiation therapy (HA-WBRT). Head computed tomography (CT) images of 15 patients were selected. The regions of interest, containing the brain, hippocampus, eyes, and lacrimal glands, were contoured manually and automatically on CT images. They were compared and evaluated for concordance rates using the Simpson coefficient. To verify the performance of dose optimization, auto-dose planning was compared with manual planning for 15 cases. All optimization plans were performed using the volumetric modulated arc therapy technique. The automatically contoured brain showed a very high concordance rate with the manually contoured brain; the Simpson coefficient was 0.990 ± 0.01. Contrastingly, the concordance rate of the hippocampal contour was low at 0.642 ± 0.15 (right) and 0.500 ± 0.16 (left); however, the rate improved to 0.871 ± 0.09 (right) and 0.852 ± 0.11 (left) with an additional 3-mm margin. For 2% of each planning target volume with the prescribed dose (D2%) and Dmean, there was no significant difference between the automatic and manual plans (35.50 Gy vs 35.23 Gy; p = 0.233 and 33.09 Gy vs 32.84 Gy; p = 0.073, respectively). The D98% was significantly better for the manual plan than for the automatic plan (25.49 Gy vs 26.11 Gy; p < 0.01). Dmax and D100% for the hippocampus did not show any significant difference between the automatic and manual plans (15.65, 16.09 Gy (right, left) vs 15.51, 15.80 Gy; p = 0.804, 0.233 and 8.08, 8.03 Gy vs 8.13, 8.01 Gy; p = 0.495, 1 respectively). The accuracy of auto-contouring for HA-WBRT can be guaranteed by providing an appropriate margin, and the precision of the auto-dose optimization was comparable to that of the manual plan.

Comparison of Physician-recorded Toxicities and Patient-reported Outcomes of Five Different Radiotherapy Methods for Prostate Cancer.

BACKGROUND/AIM: To compare five radiotherapy methods for prostate cancer. PATIENTS AND METHODS: During 2005-2018, the data of patients with non-metastatic prostate cancer were retrospectively analysed. Patients were treated with high-dose-rate brachytherapy (HDR-BT); low-dose-rate brachytherapy (LDR-BT); or external-beam radiotherapy (EBRT), including conventionally fractionated radiotherapy (CFRT), moderate-hypofractionated radiotherapy (MHRT), and ultra-hypofractionated radiotherapy (UHRT). RESULTS: In total, 496 patients (149, HDR-BT; 100, LDR-BT; 100, CFRT; 97, MHRT, and 50, UHRT) with a median follow-up of 4.3 years were enrolled. The incidence of grade ≥2 acute genitourinary toxicities was significantly lower with HDR-BT (p<0.001) than with any other radiotherapy. The cumulative incidence of late grade ≥2 genitourinary toxicities was the highest with UHRT and significantly higher (p=0.005) with UHRT than with HDR-BT. Higher symptom score peaks were noted 4 weeks after therapy for LDR-BT than for EBRT. CONCLUSION: Physician-recorded toxicities were slightly lower with HDR-BT and patient-reported outcomes tended to be worse with LDR-BT.

Implantable cardiac pacemaker failure by cumulative dose effects of flattening filter free beams.

Cumulative dose effects, which are one of the main causes of errors that occur when an implantable cardiac pacemaker (ICP) is irradiated with ionizing radiation, induce permanent failure in ICPs. Although flattening filter free (FFF) beams, which are often used in stereotactic radiotherapy, are known to have different characteristics from conventional (with flattening filter [WFF]) beams, the cumulative dose effects on ICPs with FFF beams have been under-investigated. This study investigates ICP failure induced by cumulative dose effects of FFF beams. When the ICP placed in the center of the irradiation field was irradiated with 10 MV-FFF at 24 Gy/min, the cumulative dose at which failure occurred was evaluated on the basis of the failure criteria associated with high cumulative dose as described in the American Association of Physicists in Medicine Task Group 203. The ICP failures such as a mild battery depletion at a cumulative dose of 10 Gy, pacing-output voltage change >25% at a cumulative dose of 122 Gy, and the loss of telemetry capability at cumulative dose 134 Gy were induced by cumulative dose effects. The cumulative doses by which the cumulative dose effects of FFF beams induced ICP failure were not very different from those reported in previous studies with WFF beams. Therefore, radiotherapy with FFF beams (and WFF beams) for patients with ICP requires appropriate management for minimizing the cumulative dose effects.

Effect of X-ray dose rates higher than 8 Gy/min on the functioning of cardiac implantable electronic devices.

Direct irradiation may cause malfunctioning of cardiac implantable electronic devices (CIEDs). Therefore, a treatment plan that does not involve direct irradiation of CIEDs should be formulated. However, CIEDs may be directly exposed to radiation because of the sudden intrafractional movement of the patient. The probability of CIED malfunction reportedly depends on the dose rate; however, reports are only limited to dose rates ≤8 Gy/min. The purpose of this study was to investigate the effect of X-ray dose rates >8 Gy/min on CIED function. Four CIEDs were placed at the center of the radiation field and irradiated using 6 MV X-ray with flattening filter free (6 MV FFF) and 10 MV X-ray with flattening filter free (10 MV FFF). The dose rate was 4-14 Gy/min for the 6 MV FFF and 4-24 Gy/min for 10 MV FFF beams. CIED operation was evaluated with an electrocardiogram during each irradiation. Three CIEDs malfunctioned in the 6 MV FFF condition, and all four CIEDs malfunctioned in the 10 MV FFF condition, when the dose rate was >8 Gy/min. Pacing inhibition was the malfunction observed in all four CIEDs. Malfunction occurred simultaneously along with irradiation and simultaneously returned to normal function on stopping the irradiation. An X-ray dose rate >8 Gy/min caused a temporary malfunction due to interference. Therefore, clinicians should be aware of the risk of malfunction and manage patient movement when an X-ray dose rate >8 Gy/min is used for patients with CIEDs.

Cellular and molecular mechanisms of statins: an update on pleiotropic effects.

Coronary artery disease (CAD) is the leading cause of death worldwide. The efficacy and safety of statins (3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors) in primary and secondary prevention of CAD are confirmed in several large studies. It is well known that statins have some pleiotropic, anti-atherosclerotic effects. We review the molecular mechanisms underlying the beneficial effects of statins revealed in recently published studies. Endothelial cell injury is regarded as the classic stimulus for the development of atherosclerotic lesions. In addition, the inflammatory process plays an important role in the aetiology of atherosclerosis. In particular, chronic inflammation plays a key role in coronary artery plaque instability and subsequent occlusive thrombosis. Our previous reports and others have demonstrated beneficial effects of statins on endothelial dysfunction and chronic inflammation in CAD. A better understanding of the molecular mechanism underlying the effectiveness of statins against atherosclerosis may provide a novel therapeutic agent for the treatment of coronary atherosclerosis. The present review summarizes the cellular and molecular mechanism of statins against coronary atherosclerosis.

Cytoprotective role of the fatty acid binding protein 4 against oxidative and endoplasmic reticulum stress in 3T3-L1 adipocytes.

The fatty acid binding protein 4 (FABP4), one of the most abundant proteins in adipocytes, has been reported to have a proinflammatory function in macrophages. However, the physiological role of FABP4, which is constitutively expressed in adipocytes, has not been fully elucidated. Previously, we demonstrated that FABP4 was involved in the regulation of interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) production in 3T3-L1 adipocytes. In this study, we examined the effects of FABP4 silencing on the oxidative and endoplasmic reticulum (ER) stress in 3T3-L1 adipocytes. We found that the cellular reactive oxygen species (ROS) and 8-nitro-cyclic GMP levels were significantly elevated in the differentiated 3T3-L1 adipocytes transfected with a small interfering RNA (siRNA) against Fabp4, although the intracellular levels or enzyme activities of antioxidants including reduced glutathione (GSH), superoxide dismutase (SOD) and glutathione S-transferase A4 (GSTA4) were not altered. An in vitro evaluation using the recombinant protein revealed that FABP4 itself functions as a scavenger protein against hydrogen peroxide (H2O2). FABP4-knockdown resulted in a significant lowering of cell viability of 3T3-L1 adipocytes against H2O2 treatment. Moreover, four kinds of markers related to the ER stress response including the endoplasmic reticulum to nucleus signaling 1 (Ern1), the signal sequence receptor α (Ssr1), the ORM1-like 3 (Ormdl3), and the spliced X-box binding protein 1 (Xbp1s), were all elevated as the result of the knockdown of FABP4. Consequently, FABP4 might have a new role as an antioxidant protein against H2O2 and contribute to cytoprotection against oxidative and ER stress in adipocytes.

Expression of let-7i is associated with Toll-like receptor 4 signal in coronary artery disease: effect of statins on let-7i and Toll-like receptor 4 signal.

Toll-like receptor (TLR) 4 signal plays an important role in immunity in coronary artery disease (CAD). A recent report has demonstrated that one of the let-7 family microRNAs, let-7i, directly regulates Toll-like receptor 4 (TLR4) expression and contributes to immune response. The aim of this study was to determine whether let-7i is expressed with TLR4 in patients with CAD, and whether statins (atorvastatin or rosuvastatin) might affect these levels. To determine the effects of let-7i on TLR4 expression, human THP-1 cells transfected with let-7i were analyzed for TLR4 levels. This study included 98 patients with CAD and 48 subjects without CAD (non-CAD). Patients with CAD were randomized to 12 months of treatment with atorvastatin or rosuvastatin. Monocytes were obtained from peripheral blood at baseline and after 12 months of each type of therapy. Levels of let-7i and TLR4 were measured by real-time RT-PCR and FACS. Functional approaches to let-7i showed that transfection of let-7i into human THP-1 cells resulted in regulation of TLR4 expression. Levels of let-7i were lower in the CAD group than in the non-CAD group (0.98±0.42 vs. 4.65±1.21, P<0.01). There was a negative correlation between let-7i and TLR4 levels in patients with CAD (let-7i vs. TLR4 mRNA: r=-0.60, P<0.01; let-7i vs. TLR4 MFI: r=-0.32, P<0.01). The atorvastatin group had markedly increased let-7i levels and diminished TLR4 levels (all P<0.01), whereas the rosuvastatin group showed no change in these levels. This study suggests that atorvastatin down-regulates TLR4 signal via let-7i expression in CAD patients, possibly contributing to the beneficial effects of atorvastatin on let-7i-mediated TLR4 signal in this disorder.

A cellular microRNA, let-7i, is a novel biomarker for clinical outcome in patients with dilated cardiomyopathy.

BACKGROUND: Our previous studies have reported that activation of Toll-like receptor (TLR) 4 is implicated in the etiology of human dilated cardiomyopathy (DCM). A recent report has demonstrated that let-7i, a member of the let-7 family of cellular microRNAs (miRs) miR-21, miR-126, and miR-155, directly regulate TLR4 expression. The aim of this study was to determine whether let-7i, miR-21, miR-126, and miR-155 are expressed with TLR4 in human DCM, and whether let-7i levels are related to clinical outcomes. METHODS AND RESULTS: Endomyocardial biopsy tissues were obtained from 103 patients with DCM and 37 subjects without left ventricular (LV) dysfunction as control subjects. Levels of let-7i, miR-126, and miR-155 were lower in the DCM group than in the controls, whereas levels of miR-21 and TLR4 (both mRNA and protein) were higher in the DCM group than in the control group. Levels of let-7i were negatively correlated with TLR4 protein levels in all subjects. After a mean follow-up period of 509 days, 6 DCM patients (5.8%) had died due to a cardiac cause and 15 (14.6%) had developed heart failure. When patients with DCM were divided into tertiles according to let-7i levels, log-rank analysis showed that the DCM subgroup with low let-7i levels was associated with poor clinical outcomes (P = .02). CONCLUSIONS: A decrease in let-7i may be related to poor clinical outcomes in patients with DCM.

Expression of miR-146a/b is associated with the Toll-like receptor 4 signal in coronary artery disease: effect of renin-angiotensin system blockade and statins on miRNA-146a/b and Toll-like receptor 4 levels.

The TLR4 (Toll-like receptor 4) signal plays an important role in immunity in CAD (coronary artery disease). miR-146a/b (where miR is microRNA) regulates the TLR4 downstream molecules IRAK1 (interleukin-1-receptor-associated kinase 1) and TRAF6 (tumour-necrosis-factor-receptor-associated factor 6). It has also been reported that statins and RAS (renin-angiotensin system) inhibition and have anti-atherosclerotic properties. In the present study, we have investigated whether miR-146a/b was expressed with the TLR4 signal in CAD patients, and whether combined treatment with a statin and RAS inhibition might affect these levels. A total of 66 patients with CAD and 33 subjects without CAD (non-CAD) were enrolled. Patients with CAD were randomized to 12 months of combined treatment with atorvastatin and telmisartan [an ARB (angiotensin II receptor blocker)] or atorvastatin and enalapril [an ACEI (angiotensin-converting enzyme inhibitor)]. PBMCs (peripheral blood mononuclear cells) were obtained from peripheral blood at baseline and after 12 months. Levels of miR-146a/b, IRAK1 mRNA, TRAF6 mRNA and TLR4 mRNA/TLR4 protein were significantly higher in the CAD group than in the non-CAD group (all P<0.01). Levels of miR-146a/b were positively correlated with IRAK1 mRNA and TRAF6 mRNA levels. After 12 months of treatment, these levels were markedly decreased in the ARB and ACEI groups, with the decrease in the ARB group being greater than that in the ACEI group (all P<0.05). In our 12-month follow-up study, high levels of miR-146a and TLR4 mRNA/TLR4 protein at baseline were independent predictors of cardiac events. The present study demonstrates that combined treatment with an ARB and a statin decreases miR-146a/b and the TLR4 signal in CAD patients, possibly contributing to the anti-atherogenic effects of ARBs and statins in this disorder.

Expression of microRNA-208 is associated with adverse clinical outcomes in human dilated cardiomyopathy.

BACKGROUND: Recently, microRNA-208 (miR-208) encoded by the alpha-myosin heavy chain (MHC) gene, has been shown to be involved in pathological cardiac growth, fibrosis, and up-regulation of beta-MHC expression. A recent study has also reported 2 additional myosin-expressed miRNAs (miR-208b and miR-499). The aim of this study was to determine whether miR-208, miR-208b, and miR-499 are expressed with MHC mRNA in human dilated cardiomyopathy (DCM), and whether these levels are related to left ventricular (LV) function and to clinical outcomes. METHODS AND RESULTS: Endomyocardial biopsy tissues were obtained from 82 patients with DCM and 21 subjects without LV dysfunction as controls. Levels of miR-208, miR-208b, and miR-499 were higher in DCM patients than in controls. Levels of alpha-MHC mRNA were lower in patients with DCM than in controls, whereas beta-MHC mRNA levels were higher in patients with DCM compared with controls. Levels of miR-208 were correlated with beta-MHC mRNA levels and myocardial collagen volume, whereas levels of miR-208b and miR-499 showed no correlation. After a mean follow-up of 517 days, an increase in miR-208 levels was shown to be a strong predictor of clinical outcomes (RR 3.4, 95% CI 1.1-11.2). CONCLUSIONS: This study suggests that myocardial expression of miR-208 is associated with MHC mRNA expression and with poor clinical outcomes in patients with DCM. We conclude that miR-208 may therefore be involved in the progression of human DCM.

Prospective, randomized, single-blind comparison of effects of 6 months of treatment with telmisartan versus enalapril on high-molecular-weight adiponectin concentrations in patients with coronary artery disease.

BACKGROUND: High-molecular-weight (HMW) adiponectin has important antiatherosclerotic properties. OBJECTIVES: This study compared circulating HMW adiponectin concentrations and other parameters between patients with coronary artery disease (CAD) and participants without CAD. We investigated whether treatment with statins and either telmisartan or enalapril might affect HMW adiponectin and other parameters in patients with CAD. Finally, adiponectin concentrations were compared after 6 months of treatment between CAD patients with versus without cardiac events. METHODS: Consecutive patients with stable CAD admitted to our hospital (Iwate Medical University School of Medicine, Iwate, Japan) for percutaneous coronary intervention (PCI) and stent implantation and with no previous treatment with renin-angiotensin system blockers or statins were recruited. Patients with CAD who met all eligibility criteria were randomly assigned using computer-generated numbers in a 1:1 ratio to receive telmisartan (40 mg/d) or enalapril (5 mg/d) for 6 months. In addition, all patients with CAD were treated with atorvastatin (10 mg/d). The patients without CAD received no treatment with telmisartan, enalapril, or atorvastatin. Plasma concentrations of total and HMW adiponectin were measured using a highly sensitive ELISA system before PCI or drug treatment (ie, baseline) and after 6 months of treatment. In addition, high-sensitivity C-reactive protein (hs-CRP) and homeostasis model assessment of insulin resistance (HOMA-IR) were measured. To evaluate cardiac events, follow-up coronary angiography was performed at least 6 months after PCI. RESULTS: This study included 70 patients with stable CAD (mean [SD] age, 65.8 [10.9] years; male/female ratio, 55/15) and 25 participants with normal results on coronary angiography (non-CAD) (mean age, 63.5 [11.2] years; male/female ratio, 20/5). Baseline concentrations (mean [SD]) of HMW adiponectin were significantly lower in the CAD group than in the non-CAD group (2.0 [0.3] vs 9.2 [0.5] microg/mL; P < 0.01). The ratio of HMW to total adiponectin was also lower in the CAD group than in the non-CAD group (0.37 [0.02] vs 0.53 [0.02]; P < 0.01). Baseline concentrations of HMW adiponectin were negatively correlated with hs-CRP (r = -0.60) and HOMA-IR (r = -0.30) in patients with CAD. After 6 months of treatment, the telmisartan group showed significantly increased HMW adiponectin concentrations and HMW/total adiponectin ratio (HMW, 3.7 [0.7] vs 2.1 [0.5] microg/mL; P < 0.01 vs baseline; HMW/total, 0.44 [0.02] vs 0.39 [0.02]; P < 0.05 vs baseline), whereas HOMA-IR was significantly decreased (2.86 [1.93] vs 3.39 [1.77]; P < 0.05 vs baseline). HOMA-IR at follow-up was significantly lower in the telmisartan group than in the enalapril group (2.86 [1.93] vs 3.64 [1.45]; P < 0.05). In contrast, treatment with enalapril was not associated with any significant changes in total or HMW adiponectin concentrations, HMW/total adiponectin ratio, or HOMA-IR. Both the telmisartan and the enalapril groups showed significant decreases in hs-CRP after 6 months (P < 0.05 vs baseline). After 6 months of treatment with either telmisartan or enalapril, HMW adiponectin concentrations were 0.7 (0.2) microg/mL with cardiac events versus 3.2 (0.4) microg/mL without (P < 0.05); HMW/total concentrations were 0.25 (0.03) with cardiac events versus 0.43 (0.01) without (P < 0.01). In contrast, hs-CRP concentrations were higher in patients with cardiac events than in those without cardiac events (2.42 [0.52] vs 1.86 [0.45] log10 microg/dL; P < 0.01). CONCLUSION: This study found that treatment with telmisartan and statins (but not enalapril and statins) was associated with a significant increase in HMW adiponectin concentrations and a decrease in insulin resistance in these patients with CAD.

Effect of intensive lipid-lowering therapy on telomere erosion in endothelial progenitor cells obtained from patients with coronary artery disease.

Telomere erosion of EPCs (endothelial progenitor cells) may be a key factor in endothelial cell senescence and is highly dependent on cellular oxidative damage. The aim of the present study was to investigate whether LLT (lipid-lowering therapy) with statins could attenuate EPC telomere erosion in patients with CAD (coronary artery disease). The study included 100 patients with stable CAD and 25 subjects without CAD as controls. CAD patients were randomized to 12 months of intensive LLT with atorvastatin or moderate LLT with pravastatin. EPCs were obtained from peripheral blood at baseline and after 12 months of statin therapy. Telomere length in EPCs was measured by FISH (fluorescence in situ hybridization) and oxidative DNA damage by flow cytometry of oxidized DNA bases. EPC telomere length was shorter in the CAD group than in the controls, and oxidative DNA damage to EPCs was higher in the CAD group compared with controls. After 12 months of therapy, changes in lipid profiles were greater in the intensive LLT group than in the moderate LLT group. Intensive LLT markedly increased EPC number and decreased oxidative DNA damage in EPCs (both P<0.05), with no change in telomere length. In contrast, moderate LLT did not change EPC counts or oxidative DNA damage, but showed telomere shortening (P<0.05). There was a weak negative correlation between changes in EPC number and LDL (low-density lipoprotein)-cholesterol levels after intensive LLT, whereas there was no correlation between them after moderate LLT. With in vitro culturing of EPCs subjected to oxidative stress, atorvastatin led to the prevention of EPC telomere shortening compared with pravastatin. In conclusion, the present study has demonstrated that intensive LLT may prevent EPC telomere erosion in patients with CAD, possibly contributing to the beneficial effects of intensive LLT in this disorder.

Immune modulation: role of the inflammatory cytokine cascade in the failing human heart.

Recent studies have determined that expression of inflammatory mediators, such as cytokines and chemokines, is an important factor in the development and progression of heart failure (HF). These inflammatory mediators are expressed in response to various myocardial insults, including myocardial ischemia, viral infection, and toxins, and appear to have a detrimental effect on cardiac function and prognosis in HF patients. Our previous reports have shown activation of inflammatory cytokines, particularly tumor necrosis factor-alpha (TNF-alpha), in the myocardium and peripheral monocytes in patients with HF. Indeed, sustained increases in cytokines, including TNF-alpha and its receptor, lead to monocyte phenotype transition, myocytic apoptosis, and activation of matrix metalloproteinase. This in turn modifies the interstitial matrix, augmenting further ventricular remodeling. Thus, in view of the emerging importance of TNF-alpha in the pathogenesis of HF, we review the effects of TNF-alpha on the physiology of the heart and the development of clinical strategies to target the inflammatory cytokine cascade.

Role of Toll like receptor signaling pathway in ischemic coronary artery disease.

Inflammatory process plays a fundamental role in ischemic coronary artery disease (CAD) in terms of both the etiology of atherosclerosis and the pathophysiology of CAD. In particular, chronic inflammation plays a key role in coronary artery plaque instability and subsequent occlusive thrombosis. It is therefore important to clarify the mechanism underlying the activation of the immune response in the pathogenesis of CAD. Currently 10 toll-like receptors (TLRs) have been reported in mammalian species, and these appear to recognize distinct pathogen-associated molecular patterns controlling innate immune responses. In recent studies, signaling of two forms of human TLR (TLR2 and TLR4) has been shown to be involved in the pathogenesis of CAD, establishing a key link between the progression of coronary atherosclerosis and immune response to both foreign pathogens and endogenously generated inflammatory ligands. A better understanding of TLR signal may provide a novel therapeutic agent for the treatment of CAD. This review summarizes the relationship between the pathogenesis of ischemic coronary artery disease and the human TLR system.

Local expression of Toll-like receptor 4 at the site of ruptured plaques in patients with acute myocardial infarction.

Several reports suggest that a chronic inflammatory process plays a key role in coronary artery plaque instability and subsequent occlusive thrombosis. In a previous study, we found that TLR4 (Toll-like receptor 4) mediates the synthesis of cytokines in circulating monocytes of patients with AMI (acute myocardial infarction); however, it remains unclear whether TLRs are expressed at the site of the ruptured plaque in these patients. The aim of the present study was to determine whether TLR2 and TLR4 are expressed at the site of ruptured plaques in patients with AMI and to compare this with systemic levels. The study included 62 patients with AMI, 20 patients with SA (stable angina) and 32 subjects with a normal coronary angiogram (control). Local samples from the site of the ruptured plaque were taken from patients with AMI using aspiration catheterization. Systemic blood samples from the aorta were taken from patients with AMI and SA and controls. Systemic levels of TLR2 and TLR4 were higher in patients with AMI than in patients with SA and controls. In patients with AMI, local TLR4 levels were higher than systemic levels. There was no significant difference in TLR2 levels between local and systemic samples. TLR4 immunostaining was positive in infiltrating macrophages in ruptured plaque material. Cardiac events were observed in 16 patients with AMI at the time of the 6-month follow-up study. Local and systemic levels of TLR4 were higher in patients with AMI with cardiac events than in those without. These results indicate an increase in monocytic TLR4 expression not only in the systemic circulation, but also at the site of plaque rupture. In conclusion, expression of both systemic and local plaque TLR4 may be one of the mechanisms responsible for the pathogenesis of AMI.

Association between oxidative DNA damage and telomere shortening in circulating endothelial progenitor cells obtained from metabolic syndrome patients with coronary artery disease.

Metabolic syndrome (MS) induces an increase in oxidative stress and may be an important contributory factor for coronary artery disease (CAD). Telomere shortening of endothelial progenitor cells (EPCs) may be the key factor in endothelial cell senescence. The rate of telomere shortening is highly dependent on cellular oxidative damage. This study analyzed the relationship between telomere shortening and oxidative DNA damage in EPCs obtained from CAD patients with MS and without MS. We analyzed circulating EPCs in peripheral blood obtained from 57 patients with CAD (acute myocardial infarction [AMI], n=26; stable angina pectoris [AP], n=31) and 21 age-matched healthy subjects (control). Telomere length and telomerase activity were significantly lower in CAD patients than in controls, and were lower in AMI patients than in AP patients. Oxidative DNA damage was higher in CAD patients compared with controls, and oxidative DNA damage in AMI patients was also higher than in AP patients. There was a negative correlation between telomere length and oxidative DNA damage. Telomere length and telomerase activity were lower in CAD patients with MS than in those without MS. Oxidative DNA damage in CAD patients with MS was higher than in those without MS. In our in vitro study, oxidative treatments induced telomere shortening and decrease in telomerase activity of EPCs. These results suggest that EPC telomere shortening via increased oxidative DNA damage may play an important role in the pathogenesis of CAD. In addition, MS may be related to increased oxidative DNA damage and EPC telomere shortening.

Association between toll-like receptor 8 expression and adverse clinical outcomes in patients with enterovirus-associated dilated cardiomyopathy.

BACKGROUND: In recent reports, human toll-like receptor (TLR) 8 mediates the antiviral response by recognizing single-stranded RNA. The inflammatory response against enteroviral (EV) RNA replication may play an important role in dilated cardiomyopathy (DCM). The purpose of this study was to determine whether TLR8 was expressed with EV replication in patients with enterovirus-associated DCM. METHODS: Reverse transcriptase-polymerase chain reaction analysis was performed to screen the detection of myocardial EV RNA in 198 consecutive patients with DCM. Seventy-two EV RNA-positive patients with DCM and 20 control samples constituted the study population of the present study. Levels of TLR8 and myeloid differentiation factor (MyD) 88 adaptor protein mRNA and EV RNA (plus- and minus-strand RNAs) were measured by real-time RT-PCR. Immunohistochemistry was performed to identify the cellular source of these molecules. RESULTS: Toll-like receptor 8 and MyD88 mRNA levels were higher in patients with DCM than in controls (P < .001). Immunostainings of TLR8, MyD88, and EV protein showed localization of these proteins in cardiac myocytes in patients with DCM. After a mean follow-up of 426 days, clinical outcomes (development of heart failure n = 11, cardiac death n = 3) were associated with increased levels of TLR8 and MyD88 (P < .05). Multivariate analysis showed that TLR8 (relative risk 3.2, 95% CI 1.6-6.2) was a strong predictor of heart failure and cardiac death after adjustment for baseline characteristics. CONCLUSION: Toll-like receptor 8 and MyD88 expressions may be involved in the immune response to EV replication in enterovirus-associated DCM. In addition, TLR8 may provide important prognostic information in patients with enterovirus-associated DCM.

A novel activator of C-C chemokine, FROUNT, is expressed with C-C chemokine receptor 2 and its ligand in failing human heart.

BACKGROUND: A novel activator of C-C chemokines, FROUNT, directly binds C-C chemokine receptor (CCR) 2 and plays a central role in the chemokine system. Activation of the chemokine system appears to be involved in the pathogenesis of congestive heart failure (CHF). The purpose of this study was to determine whether FROUNT is expressed with CCR2 and its ligand (CCL2) in failing human heart. METHODS AND RESULTS: We examined endomyocardial biopsy tissues obtained from 71 patients with CHF (HF group) and 20 subjects without CHF (non-HF group). FROUNT, CCR2, and CCL2 mRNA levels were higher in the HF group than in the non-HF group (P < .001). FROUNT mRNA levels were positively correlated with CCR2 and CCL2 mRNA levels in the HF group. FROUNT and CCL2 signal was seen in the cytoplasm of cardiac myocytes in failing hearts. Levels of FROUNT mRNA were negatively correlated with left ventricular ejection fraction. FROUNT, CCR2, and CCL2 mRNA levels were higher in the severe HF subgroup than in the mild HF subgroup. CONCLUSIONS: The expression of FOUNT-mediated CCL2/CCR2 may have important implications in the pathogenesis of CHF. The CCL2/CCR2 pathway via FROUNT may influence the clinical severity of CHF.