Pharmacokinetics and pharmacodynamics of recombinant soluble thrombomodulin in disseminated intravascular coagulation patients with renal impairment.

Recombinant human soluble thrombomodulin (TM-α) was recently developed as an anticoagulant for patients with disseminated intravascular coagulation (DIC). However, the pharmacokinetics and pharmacodynamics of TM-α in DIC patients with severe renal impairment have not yet been elucidated. We investigated the pharmacokinetics and pharmacodynamics of TM-α in DIC patients with severe renal impairment. Eleven DIC patients with severe renal impairment (creatinine clearance <30 mL/min) and 10 DIC patients without severe renal impairment (creatinine clearance ≥30 mL/min) were included in this study. In all patients, a dose of 380 U/kg of TM-α was administered during a 30-min infusion. Blood samples were taken before the start of the first TM-α administration, and at 0.5, 2, 4, 8, and 24 h after the start of administration. Although the clearance of TM-α in the patients with renal impairment was 80% of that in the patients without renal impairment, none of the pharmacokinetic values were significantly different between the groups. In the pharmacokinetic simulation, however, the trough levels of TM-α increased gradually in the patients with renal impairment when the same dose of TM-α was repeatedly administered. After the administration of TM-α, the prothrombinase activities in the patients in both groups were sufficiently inhibited during the observation period. Although the pharmacokinetic values in DIC patients with severe renal impairment were only slightly different from those in DIC patients without severe renal impairment, we need to pay attention to the elevation of the trough levels of TM-α when the same dose of TM-α is repeatedly administered.

Disseminated intravascular coagulation (DIC) at an early phase of trauma continuously proceeds to DIC at a late phase of trauma.

The data from 254 patients with severe trauma were retrospectively analyzed. The patients were subdivided into disseminated intravascular coagulation (DIC) and non-DIC. There was a difference in the incidence of the continuous progression from the early to late phase of DIC between the patients with and without DIC on day 0. While 2 of 9 patients who newly developed late-phase DIC were complicated with sepsis, none of the 32 patients who showed a continuous progression of DIC from the early to late phase of trauma developed sepsis. The DIC and Sequential Organ Failure Assessment scores on day 0 were independent factors that predicted the continuous progression of the DIC from the early to late phase of trauma. Trauma itself, but not sepsis, contributes to the continuous progression of DIC from the early to late phase of trauma. The severity of DIC and organ dysfunction are involved in the pathogenesis of this continuous progression.

Dramatic changes of the gut flora immediately after severe and sudden insults.

BACKGROUND: The gut flora is crucially involved in host homeostasis. However, the changes in the gut flora during the early phase of a critical illness are unknown. AIMS: We investigated the changes in the gut flora at an early phase of severe insult in critically ill patients. METHODS: Fifteen patients who experienced a sudden and severe insult were studied, along with 12 healthy volunteers as the control group. Fecal samples were acquired from the subjects by swabs of the rectum within 6 h after admission to the emergency room (day 0). Samples were serially collected from patients until day 14. Samples were also collected from control subjects. RESULTS: On day 0, total bacterial counts were decreased to one-thousandth the number of the control subjects, in particular, obligate anaerobes and Lactobacillus were significantly decreased. In addition, on day 0, the major short-chain fatty acids of the patients were significantly lower than those of the control subjects. The gut flora and the concentrations of major short-chain fatty acids did not recover to normal levels. In contrast, Enterococcus and Pseudomonas increased during the study period. CONCLUSIONS: The gut flora in critically ill patients changed immediately after a severe insult. The concentrations of the three major short-chain fatty acids were immediately decreased in tandem with the destruction of the gut flora. The gut flora and the concentration of major short-chain fatty acids did not improve during the first 2 weeks after hospital admission. At the same time, the number of harmful bacteria gradually increased.

Imbalance between macrophage migration inhibitory factor and cortisol induces multiple organ dysfunction in patients with blunt trauma.

Migration inhibitory factor (MIF) is associated with multiple organ dysfunction syndrome (MODS) in patients with systemic inflammatory response syndrome (SIRS). Our purposes were to determine the serum MIF, cortisol, and tumor narcosis factor-α (TNF-α) and to investigate the influences of the balance between the levels of MIF and cortisol in patients with blunt trauma. The cortisol levels were identical between the patients with and without MODS. However, the MIF and TNF-α levels in the patients with MODS were statistically higher than those of the patients without MODS. The cortisol/MIF ratios in the patients with MODS were statistically higher than those of the patients without MODS. The results show that MIF and TNF-α play an important role together in posttraumatic inflammatory response. An excessive serum MIF elevation overrides the anti-inflammatory effects of cortisol and leads to persistent SIRS followed by MODS in blunt trauma patients.

Disseminated intravascular coagulation at an early phase of trauma is associated with consumption coagulopathy and excessive fibrinolysis both by plasmin and neutrophil elastase.

BACKGROUND: The aims of the present study were to confirm the consumption coagulopathy of disseminated intravascular coagulation with the fibrinolytic phenotype at an early phase of trauma and to test the hypothesis that thrombin-activatable fibrinolysis inhibitor, neutrophil elastase, and plasmin contribute to the increased fibrinolysis of this type of disseminated intravascular coagulation. Furthermore, we hypothesized that disseminated intravascular coagulation at an early phase of trauma progresses dependently to disseminated intravascular coagulation with a thorombotic phenotype from 3 to 5 days after injury. METHODS: Fifty-seven trauma patients, including 30 patients with disseminated intravascular coagulation and 27 patients without disseminated intravascular coagulation, were studied prospectively. Levels of thrombin-activatable fibrinolysis inhibitor, tissue-type plasminogen activator plasminogen activator inhibitor-1 complex, plasmin alpha2 plasmin inhibitor complex, D-dimer, neutrophil elastase, and fibrin degradation product by neutrophil elastase were measured on days 1, 3, and 5 after trauma. The prothrombin time, fibrinogen, fibrin/fibrinogen degradation product, antithrombin, and lactate also were measured. RESULTS: Independent of the lactate levels, disseminated intravascular coagulation patients showed a prolonged prothrombin time, lesser fibrinogen and antithrombin levels, and increased levels of fibrin/fibrinogen degradation product on day 1. Disseminated intravascular coagulation diagnosed on day 1 continued to late-phase disseminated intravascular coagulation on days 3 and 5 after trauma. Increased levels of tissue-type plasminogen activator plasminogen activator inhibitor-1 complex, plasmin alpha2 plasmin inhibitor complex, D-dimer, neutrophil elastase, and fibrin degradation product by neutrophil elastase but not thrombin-activatable fibrinolysis inhibitor were observed in the disseminated intravascular coagulation patients. No correlation was observed between plasmin alpha2 plasmin inhibitor complex and fibrin degradation product by neutrophil elastase in disseminated intravascular coagulation patients. Multiple regression analysis showed the disseminated intravascular coagulation score and the tissue-type plasminogen activator plasminogen activator inhibitor-1 complex levels on day 1 to correlate with the total volume of transfused blood. Patient prognosis deteriorated in accordance with the increasing disseminated intravascular coagulation severity. CONCLUSION: Disseminated intravascular coagulation at an early phase of trauma is associated with consumption coagulopathy and excessive fibrinolysis both by plasmin and neutrophil elastase independent of hypoperfusion and continues to disseminated intravascular coagulation at a late phase of trauma. Increased fibrinolysis requires more blood transfusions, contributing to a poor patient outcome.

Scavenging free radicals improves endothelial dysfunction in human coronary arteries in vivo.

The effect of a novel free radical scavenger, edaravone, on coronary endothelial dysfunction was examined in patients who had no significant stenosis of coronary arteries, to elucidate the role of free radicals on coronary endothelial dysfunction. The coronary blood flow (CBF) responses to acetylcholine (ACh) were measured by quantitative coronary arteriography and the intracoronary Doppler technique before and after the administration of edaravone. Twenty-four patients were divided into two groups on the basis of CBF responses to ACh; those with "attenuated" (%Delta CBF < 300%, n = 12) and "normal" (%Delta CBF > 300%, n = 12) flow responses. An intracoronary infusion of edaravone significantly improved ACh-induced increases in CBF in patients with attenuated flow responses; however, edaravone had no effect in those with normal flow responses (36.8% +/- 7.3% vs 0.0% +/- 5.1%, P < 0.01). The plasma levels of nitric oxide compounds (NOx) in the attenuated response group were lower than those in the normal group (35.7 +/- 2.3 vs 49.4 +/- 6.2 muM, P < 0.01) and correlated with the magnitude of CBF improvement by edaravone (r = 0.566, P < 0.01). The plasma level of malondialdehyde and 4-hydroxynonenal, which indicates the level of oxidative stress, in the attenuated group was higher than that in the normal group (6.9 +/- 0.9 vs 3.3 +/- 0.5 muM, P < 0.01) and correlated with the magnitude of CBF improvement by edaravone (r = 0.854, P < 0.01). A free radical scavenger improved the ACh-induced CBF response in patients with coronary atherosclerosis in vivo. Therefore, the current results suggest that scavenging free radicals has a beneficial effect for patients with coronary endothelial dysfunction.

Green tea catechins improve human forearm endothelial dysfunction and have antiatherosclerotic effects in smokers.

BACKGROUND: Because green tea reduces cardiovascular and cerebrovascular risk, the purpose of this study aimed to elucidate the effect of green tea catechins (GTC) on endothelial dysfunction in smokers. METHODS AND RESULTS: The 30 healthy male smokers were divided into 3 groups and given green tea beverages containing 0 mg (control group), 80 mg (medium-dose group) or 580 mg (high-dose group) of GTC daily for 2 weeks. Endothelial-dependent and- independent vasodilatation was investigated by measuring the forearm blood flow (FBF) responses to acetylcholine and sodium nitroprusside using venous occlusion strain-gauge plethysmography. The FBF response to acetylcholine significantly increased at 2 h and 1 and 2 weeks after GTC intake in the high-dose group, but no increase was observed in the other groups. FBF responses to sodium nitroprusside did not alter in any group at any time point. A significant increase in plasma nitric oxide and a decrease in asymmetrical dimethylarginine, malondealdehyde and 4-hydroxynonenal, C-reactive protein, monocyte chemotactic protein-1, and soluble CD40 ligand levels were detected after chronic consumption of high-dose GTC. CONCLUSIONS: GTC have antiatherosclerotic effects on dysfunctional vessels in smokers through increasing the level of nitric oxide and reducing oxidative stress.

Sivelestat (selective neutrophil elastase inhibitor) improves the mortality rate of sepsis associated with both acute respiratory distress syndrome and disseminated intravascular coagulation patients.

Neutrophil elastase plays an important role in the development of acute respiratory distress syndrome (ARDS) and disseminated intravascular coagulation (DIC) in sepsis. Sivelestat is a selective neutrophil elastase inhibitor. It is possible that sivelestat improves the outcome of septic patients associated with ARDS and DIC. A retrospective data analysis of septic patients associated with ARDS and DIC was conducted to investigate the effects of sivelestat. Observational period was 5 days after admission to intensive care unit (ICU). The study included 167 septic patients associated with ARDS and DIC. Control group included 133 patients without sivelestat, and sivelestat group included 34 patients started to deadministered sivelestat on the admission to ICU. The lung injury scores and Pa(O2)/Fl(O2) ratio of the sivelestat group were significantly more severe than those of the control group from days 1 to 4. On day 5, the lung injury score and Pa(O2)/Fl(O2) ratio of the sivelestat group improved to the same levels of those of the control group. The DIC score of sivelestat group improved on day 3 in comparison to day 1, and those of control group remained unchanged until day 4. The length of ICU stay of the sivelestat group was significantly shorter than that of the control group. A stepwise multiple logistic-regression analysis showed the sivelestat administration to be an independent predictor of survival of the septic patients associated with both ARDS and DIC. The length of ICU stay of the sivelestat group was significantly shorter than that of the control group. In addition, sivelestat administration was found to be an independent predictor of survival of those patients.

Application of the Japanese Association for Acute Medicine disseminated intravascular coagulation diagnostic criteria for patients at an early phase of trauma.

INTRODUCTION: To validate the diagnostic criteria for disseminated intravascular coagulation (DIC) established by the Japanese Association for Acute Medicine (JAAM) at an early stage of trauma and to evaluate the hypothesis that the JAAM criteria can diagnose DIC with a higher sensitivity than the International Society on Thrombosis and Haemostasis (ISTH) overt DIC criteria. MATERIALS AND METHODS: Based on a review of medical records, the data of 314 trauma patients were retrospectively obtained at 4 time points within 24 hr after arrival to the Emergency Department. RESULTS: One hundred and forty-one JAAM DIC patients (44.9%) showed differences in the prevalence of massive bleeding and multiple organ dysfunction syndrome (MODS), and the outcome in comparison to the non-DIC patients. A stepwise logistic regression analysis showed that the maximum JAAM DIC scores independently predicted the patient death. All of the patients who developed ISTH overt DIC could be identified by the JAAM DIC criteria at early time points. The mortality rate and the incidence of massive bleeding and MODS of the patients with the ISTH overt DIC were higher than those only met the JAAM DIC criteria. Stepwise increases in the ISTH overt DIC scores and the incidence of the overt DIC were observed in accordance with the increases in the JAAM DIC scores. While the mortality rates were identical, there were marked differences in the incidence of MODS and Sequential Organ Failure Assessment scores between the DIC patients associated with trauma and sepsis. CONCLUSIONS: The results show that the JAAM scoring system has acceptable validity for the DIC diagnosis at an early phase of trauma, and also that the scoring system can diagnose DIC with a higher sensitivity than the criteria of the ISTH overt DIC. Bleeding as well as MODS may affect the prognosis of the patients associated with DIC.

Disseminated intravascular coagulation with a fibrinolytic phenotype at an early phase of trauma predicts mortality.

INTRODUCTION: Disseminated intravascular coagulation (DIC) with an antifibrinolytic phenotype is characterized by microvascular thrombosis leading to poor outcome at the late-stage of trauma. To test the hypothesis that DIC with a fibrinolytic phenotype at an early stage of trauma also contributes to a poor outcome due to severe bleeding, we conducted a retrospective, cohort study. MATERIALS AND METHODS: The subjects included 314 consecutive severe trauma patients. A systematic review of medical records of the patients was conducted to provide the base line characteristics and DIC-related variables. The data of these variables were obtained at 4 time points within 24 hr after arrival to the emergency department (ED); Time Point 1, immediately after arrival to the ED to 4 hr after arrival; Time Point 2, 4 to 8 hr after arrival; Time Point 3, 8 to 16 hr after arrival; Time Point 4, 16 to 24 hr after arrival. RESULTS: Nonsurvivors (87.3%, 48/55) met the Japanese Association for Acute Medicine (JAAM) DIC criteria showing lower fibrinogen levels, a prolonged prothrombin time, and higher fibrin/fibrinogen degradation products (FDP) and D-dimer levels in comparison to those of the 289 survivors. The FDP/D-dimer ratio and lactate level were significantly higher in the nonsurvivors than those of the survivors. Lower fibrinogen levels and higher FDP/D-dimer ratio suggest fibrinogenolysis in DIC of the nonsurvivors. Furthermore a stepwise logistic regression analysis showed that the JAAM DIC score, levels of fibrinogen, FDP and lactate at Time Point 1 are independent predictors of death. Low levels of fibrinogen and high FDP but not D-dimer predict massive bleeding at an early stage of trauma. The optimal cutoff points for the prediction of death and massive bleeding were fibrinogen (1.90, 1.90 g/L) and FDP (35.2, 68.7 mg/L), respectively. CONCLUSIONS: DIC with a fibrinolytic phenotype modified through fibrinogenolysis at an early phase of trauma contributes to poor prognosis due to massive bleeding. Tissue hypoperfusion may be involved in the pathogenesis of this type of DIC.

TNF-alpha employs a protein-tyrosine phosphatase to inhibit activation of hepatocyte growth factor receptor and hepatocyte growth factor-induced endothelial cell proliferation.

TNF-alpha impairs endothelial cell growth and angiogenesis. The anti-angiogenic effects of TNF-alpha have mainly been explained by its modulating vascular endothelial growth factor (VEGF)-specific angiogenic pathway. Hepatocyte growth factor (HGF) also promotes the growth of vascular endothelial cells and the development of new blood vessels through interaction with its specific receptor, c-met. However, it is little known whether TNF-alpha interacts with the HGF system or not. In this study, we examined the effect of TNF-alpha on HGF receptor function. In human umbilical venous endothelial cells (HUVEC), TNF-alpha acutely inhibited the phosphorylation and activation of c-met induced by HGF. The ability of TNF-alpha to inhibit HGF-induced c-met activity was impaired by sodium orthovanadate, suggesting that the inhibitory effect of TNF-alpha was mediated by a protein-tyrosine phosphatase. Treatment of HUVEC with TNF-alpha impairs the ability of HGF to activate MAPK and Akt, and this effect was blocked by SOV. HGF-induced c-met responses specifically associated with endothelial cell proliferation and mitogen-activated protein kinase activation were also inhibited by TNF-alpha, and these were reversed by sodium orthovanadate. HGF-induced SHP-1 (a cytoplasmic protein-tyrosine phosphatase) and pretreatment of HUVEC with TNF-alpha prior to HGF treatment resulted in substantial increase in the amount of SHP-1. These data suggest that TNF-alpha employs a protein-tyrosine phosphatase and may exert its anti-angiogenic function in part by modulating the HGF-specific angiogenic pathway in pathological settings.

Effects of antithrombin III in patients with disseminated intravascular coagulation diagnosed by newly developed diagnostic criteria for critical illness.

A study was conducted to test the hypotheses that antithrombin III (antithrombin) improves disseminated intravascular coagulation (DIC) when applied to DIC patients diagnosed by sensitive criteria and that the administration of high-dose antithrombin is a beneficial treatment for DIC. Twenty-three DIC patients diagnosed based on the Japanese Association for Acute Medicine (JAAM) DIC diagnostic criteria were treated with either high-dose (60 IU/kg/day) or low-dose (30 IU/kg/day) antithrombin concentrates for 3 days. The clinical conditions that cause DIC were restricted to systemic inflammatory response syndrome (SIRS) and sepsis. Data of antithrombin activity, platelet counts, coagulation and fibrinolytic markers, and DIC scores before antithrombin administration (day 0), on days 1 to 3, and on day 7 were retrospectively collected from computer-based records. Patients who met the JAAM DIC criteria were administered either high-dose (12 patients) or low-dose (11 patients) antithrombin. The patients' backgrounds and antithrombin activity (high dose, 51.5 +/- 14.5%; low dose, 62.6 +/- 19.3%; P = .153) on day 0 were identical in the 2 groups. The JAAM DIC score and prothrombin time ratio on day 7 significantly improved when compared with those on day 0. However, mortality at 28 days as well as interaction within the antithrombin doses administered showed no difference. There were also no differences in the time course of the platelet counts, coagulation and fibrinolytic markers, and DIC scores in the 2 groups. The authors conclude that the effects of antithrombin on prognosis and coagulation and fibrinolytic parameters are independent of the doses administered in patients with SIRS/sepsis-associated DIC.

Diagonal earlobe crease are associated with shorter telomere in male Japanese patients with metabolic syndrome.

BACKGROUND: Diagonal earlobe crease (ELC) have been proposed as a marker of generalized atherosclerosis, so in the present study it was investigated whether individuals with ELC have a shortened telomere, which correlates with an accelerated cell turnover and premature aging, leading to atherosclerosis. METHODS AND RESULTS: The mean terminal restriction fragment (TRF) was determined by Southern blot hybridization in the peripheral blood cells of 34 male Japanese patients with metabolic syndrome (MetS) who were under 70 years of age with (n=17) and without (n=17) bilateral ELC, and assessed the relationship of ELC to atherosclerotic cardiovascular disease (AVD). The results showed that the TRF was shorter in the MetS patients with ELC in comparison to age- and risk-factor-matched MetS patients without ELC (7.6+/-1.1 kbp vs 8.6+/-1.2 kbp; P<0.05). ELC were present in 13 patients in the AVD group (n=18), but only 4 patients in the non-AVD group (n=16) had ELC (72.2% and 25% respectively; P<0.05). CONCLUSIONS: These findings suggest that ELC is a useful dermatological indicator of an accelerated aging process, as suggested by excessive telomere loss, and might be a useful indirect marker of high-risk patients.

A percentage analysis of the telomere length in Parkinson's disease patients.

Telomeres are the repeated sequences at the chromosome ends which undergo shortening with cell division. The telomere shortening of the peripheral leukocytes is also facilitated by enhanced oxidative stress in various kinds of disease including ischemic heart disease, diabetes mellitus, apoplexy, and Alzheimer's disease. Telomere shortening in Parkinson's disease (PD) has not yet been reported. The pathogenesis for PD is also regarded to be associated with oxidative stress. We investigated 28 Japanese male PD patients ages 47-69. Although we could not find a statistical difference in the mean telomere length of peripheral leukocytes between the PD patients and the control participants, we found the mean telomere lengths to be shorter than 5 kb in only the PD patients and a significant PD-associated decrease in the telomeres with a length ranging from 23.1 to 9.4 kb in the patients in their 50s and 60s. These observations suggest that telomere shortening is accelerated in PD patients in comparison to the normal population.

The response of antithrombin III activity after supplementation decreases in proportion to the severity of sepsis and liver dysfunction.

The decrease in the antithrombin III activity is thought to result from consumption by ongoing coagulation, degradation by neutrophil elastase, capillary leak syndrome, and impaired synthesis. A retrospective data analysis of patients with sepsis was conducted to investigate the response of antithrombin III activity after supplementation in patients with sepsis, and to determine what factors affect the response of antithrombin III activity. The study included 42 patients with sepsis, 75 patients with severe sepsis, and 65 patients with septic shock, who were administered antithrombin III. Antithrombin III activity, platelet counts, coagulation, and fibrinolytic markers were collected before administration and 24 h after the supplementation. In the patients with septic shock, the response of antithrombin III activity after supplementation was 0.37% +/- 1.21%/IU per kg body weight, which was significantly lower in comparison with those in the patients with sepsis (1.81 +/- 1.75; P < 0.001) or severe sepsis (1.36 +/- 1.65; P < 0.001). The patients with liver dysfunction had significantly lower response to antithrombin III activity than that of the patients without liver dysfunction (P < 0.0001). A stepwise multiple linear regression analysis revealed that the severity of sepsis and liver function were independent predictors for the response to antithrombin III activity. These results suggest that the response to antithrombin III supplementation may be affected by both a systemic inflammation and impaired synthesis in patients with sepsis.

Insufficient production of urinary trypsin inhibitor for neutrophil elastase release after cardiac arrest.

To investigate the relationship between the inflammatory responses and postresuscitation syndrome, we prospectively examined the serial changes of neutrophil elastase (NE), urinary trypsin inhibitor (UTI), and TNF-alpha) in successfully resuscitated patients after out-of-hospital cardiac arrest. This study included 36 patients with out-of-hospital cardiac arrests who were admitted to our intensive care unit after return of spontaneous circulation (ROSC). The 11 patients who restored to spontaneous circulation within 30 min after cardiac arrest were defined as the short cardiac arrest group. The 25 patients who restored to spontaneous circulation more than 30 min after cardiac arrest were defined as the long cardiac arrest group. Eight healthy volunteers served as control group. Daily plasma levels of NE, UTI, and TNF-alpha were measured from days 1 to 5 after ROSC. The releases of NE from activated neutrophil just after ROSC in the patients with long cardiac arrest were statistically higher than those of the short cardiac arrest group. There was a significant correlation between the NE levels and the duration of cardiac arrest. A high but insufficient production of UTI for NE release was observed on day 1, especially in the patients with a long duration of cardiac arrest. The cerebral performance category of the short cardiac arrest group was better than that of the long cardiac arrest group. Although high levels of TNF-alpha were sustained in the postresuscitation period, the levels of TNF-alpha were unrelated to the duration of cardiac arrest. In conclusion, a massive release of NE in proportion to the duration of cardiac arrest and an insufficient production of UTI for the NE release may contribute to the pathogenesis of postresuscitation syndrome after out-of-hospital cardiac arrest.

An analysis of telomere length in sarcoidosis.

We investigated telomere (terminal restriction fragment [TRF]) length in 111 patients with sarcoidosis regarding both the mean TRF length and the telomere length distribution. A significant decrease was observed in the mean TRF length in sarcoidosis patients in comparison to the age-matched controls, whereas a decreased telomere length was only associated with age in men. The mean TRF shortening seemed to be accelerated in men in their 30s and 50s and in women in their 40s and 50s. We also found a significant decrease with age of telomeres with lengths of 9.4-6.6 kb in men and women in their 20s and an increase of telomeres with lengths of 4.4-2.3 kb in men and women in their 20s and in men in their 50s in sarcoidosis patients versus in the controls who were in their 20s and 50s. These findings suggest the occurrence of age-advanced changes in telomere length in patients with sarcoidosis, regardless of the patient age at the onset of sarcoidosis.

Change in the telomere length distribution with age in the Japanese population.

Telomeres play a role in cellular aging and they may also contribute to the genetic basis of human aging and longevity. A gradual loss of the telomeric repeat sequences has been reported in adult tissue specimens. This study determined the percentage of telomere restriction fragment in various molecular-sized regions in addition to measuring the average telomere length. Mean telomere restriction fragment (TRF) length was determined by Southern blot analysis using a longer telomeric repeat probe with higher sensitivity. A significant decrease in longer telomere fragments and a quick increase in the shortest fragments were observed, especially in male subjects. There was a tendency that the age-adjusted telomere length was longer in females than that observed in males, while males lose the telomeric sequence faster than females. These data indicated that the percentage of longer telomeres fragments decreased, while the shortest fragments increased quickly with age. In addition, the longest telomere fragments decreased and the short fragments increased with a relatively stable frequency with age. There was also a significant difference in the longest telomere fragment percentage between males and female in their 40s and 50s, whereas no difference was observed in the mean TRF length. Interestingly, the changing rate of the longest and the shortest range group of TRF percentage associated with aging seemed quite different between before and after 50-year old with a gender-related contrast. This contrast implies a drastic change around the age of 50 of unknown factors that affect telomere attrition.

Transient receptor potential (TRP) protein 7 acts as a G protein-activated Ca2+ channel mediating angiotensin II-induced myocardial apoptosis.

Transient receptor potential (TRP) proteins have been identified as cation channels that are activated by agonist-receptor coupling and mediate various cellular functions. TRPC7, a homologue of TRP channels, has been shown to act as a Ca2+ channel activated by G protein-coupled stimulation and to be abundantly expressed in the heart with an as-yet-unknown function. We studied the role of TRPC7 in G protein-activated signaling in HEK293 cells and cultured cardiomyocytes in vitro transfected with FLAG-tagged TRPC7 cDNA and in Dahl salt-sensitive rats with heart failure in vivo. TRPC7-transfected HEK293 cells showed an augmentation of carbachol-induced intracellular Ca2+ transient, which was attenuated under a Ca2+-free condition or in the presence of SK&F96365 (a Ca2+-permeable channel blocker). Upon stimulation with angiotensin II (Ang II), cultured neonatal rat cardiomyocytes transfected with TRPC7 exhibited a significant increase in apoptosis detected by TUNEL staining, accompanied with a decrease in the expression of atrial natriuretic factor and destruction of actin fibers, as compared with non-transfected cardiomyocytes. Ang II-induced apoptosis was inhibited by CV-11974 (Candesartan; Ang II type 1 [AT1] receptor blocker), SK&F96365, and FK506 (calcineurin inhibitor). In Dahl salt-sensitive rats, apoptosis and TRPC7 expression were increased in the failing myocardium, and a long-term treatment with temocapril, an angiotensin-converting enzyme inhibitor, suppressed both. Our findings suggest that TRPC7 could act as a Ca2+ channel activated by AT1 receptors, leading to myocardial apoptosis possibly via a calcineurin-dependent pathway. TRPC7 might be a key initiator linking AT1-activation to myocardial apoptosis, and thereby contributing to the process of heart failure.