Suppressed heat shock protein response in the kidney of exercise-trained diabetic rats.

Impaired expression of heat shock proteins (HSPs) and increased oxidative stress may contribute to the pathophysiology of diabetes by disrupted tissue protection. Acute exercise induces oxidative stress, whereas exercise training up-regulates endogenous antioxidant defenses and HSP expression. Although diabetic nephropathy is a major contributor to diabetic morbidity, information regarding the effect of HSPs on kidney protection is limited. This study evaluated the effects of eight-week exercise training on kidney HSP expression and markers of oxidative stress at rest and after acute exercise in rats with or without streptozotocin-induced diabetes. Induction of diabetes increased DNA-binding activity of heat shock factor-1, but decreased the expression of HSP72, HSP60, and HSP90. The inflammatory markers IL-6 and TNF-alpha were increased in the kidney tissue of diabetic animals. Both exercise training and acute exercise increased HSP72 and HSP90 protein levels only in non-diabetic rats. On the other hand, exercise training appeared to reverse the diabetes-induced histological changes together with decreased expression of TGF-beta as a key inducer of glomerulosclerosis, and decreased levels of IL-6 and TNF-alpha. Notably, HSP72 and TGF-beta were negatively correlated. In conclusion, impaired HSP defense seems to contribute to kidney injury vulnerability in diabetes and exercise training does not up-regulate kidney HSP expression despite the improvements in histopathological and inflammatory markers.

Synergistic Expression of Histone Deacetylase 9 and Matrix Metalloproteinase 12 in M4 Macrophages in Advanced Carotid Plaques.

OBJECTIVE/BACKGROUND: Expression patterns and association with cell specific gene expression signatures of the epigenetic regulator histone deacetylase 9 (HDAC9) and matrix metalloproteinase 12 (MMP12) in human plaque are not known. METHODS: This was a prospective cohort study. Genome wide expression analysis was performed in carotid, femoral, aortic plaques (n = 68) and left internal thoracic (LITA) controls (n = 28) and plaque histological severity assessed. Correlation and hierarchical cluster analysis was utilised. RESULTS: HDAC9 was associated with MMP12 expression in carotid plaques (r = .46, p = .012) and controls (r = -.44, p = .034). HDAC9 and MMP12 clustered with inflammatory macrophage markers but not with smooth muscle cell (SMC) rich markers. In plaques from all arterial sites, MMP12 but not HDAC9 showed positive correlation (p < .05) with M2 and M4 polarized macrophage markers, and negative correlation with SMC rich signatures. In the carotid plaques, all M4 macrophage markers associated with MMP12 and HDAC9. The negative association of MMP12 with SMC rich signatures was pronounced in the carotid plaques. Neither HDAC9 nor MMP12 associated consistently with plaque stabilisation or thrombosis related genes. Immunohistochemistry further supported the association between HDAC9 and MMP12 in atherosclerotic plaques. CONCLUSION: M4 macrophages are a possible source for HDAC9 and MMP12 expression in advanced human plaques.

Extensive white matter changes predict stroke recurrence up to 5 years after a first-ever ischemic stroke.

BACKGROUND: White matter changes (WMCs), a surrogate for small-vessel disease (SVD), have been shown to be associated with a major negative influence on cognition, mood and functioning in daily life. We aimed to investigate whether severe WMCs are a risk factor for recurrent ischemic stroke in a long-term follow-up. METHODS: 320 consecutive patients admitted to hospital with a first-ever ischemic stroke were included in the study and followed up for 12 years using extensive national registers. Patients were aged between 55 and 85 years, with a mean age of 70.8 years. WMCs were rated using MRI and stratified into two grades: absent to moderate WMCs versus severe WMCs. Univariate analysis was performed using binary logistic regression analysis, Kaplan-Meier log rank analysis and life table function. To control for factors such as age, education and cardiovascular risk factors, a multivariate Cox regression proportional hazards analysis was made with forced entry. RESULTS: At least one recurrent stroke, nonfatal or fatal, was diagnosed in 76 (23.8%) patients at 5 years and in 127 (39.7%) patients at 12 years. In univariate analysis, only advancing age was associated with WMCs. The cumulative 5-year recurrence risk was 24.5% [95% confidence interval (95% CI) 23.8-25.2] for patients with absent to moderate WMCs and 39.1% (95% CI 38.1-40.1) for patients with severe WMCs. The cumulative 12-year recurrence risk was 48.1% (95% CI 45.5-50.7) for patients with absent to moderate WMCs and 60.9% (95% CI 56.7-65.1) for patients with severe WMCs. In Cox regression proportional hazards analysis, independent predictors of recurrent stroke at 5 years were severe WMCs [hazard ratio (HR) 1.80, 95% CI 1.11-2.95], atrial fibrillation (HR 1.81, 95% CI 1.09-3.02), hypertension (HR 1.69, 95% CI 1.05-2.71) and peripheral arterial disease (HR 1.89, 95% CI 1.06-3.38). At 12 years, only increasing age remained as an independent predictor (HR 1.04, 95% CI 1.02-1.07). In receiver operating characteristic analysis, the area under the curve for severe WMCs was 0.58 (95% CI 0.51-0.65) for the prediction of stroke recurrence within 5 years. CONCLUSIONS: In our well-defined cohort of poststroke patients, the presence of severe WMCs was an indicator of stroke recurrence up to 5 years after a first-ever ischemic stroke. WMCs can be considered as an SVD marker that summarizes the effects of several classical risk factors on the small-vessel brain network and therefore can be used as a score for risk stratification of stroke recurrence. Our findings further underline the poor long-term prognosis of cerebral SVD.

Small-vessel disease relates to poor poststroke survival in a 12-year follow-up.

OBJECTIVE: We sought to compare ultra-long-term poststroke survival in small-vessel disease (SVD) vs non-SVD subtype of stroke. METHODS: We followed patients hospitalized with acute ischemic stroke (age 55-85) for 12 years. The diagnosis of SVD was based on the criteria of Trial of Org 10172 in Acute Stroke Treatment. A detailed medical history regarding the relevant risk factors was obtained. Stroke severity was assessed with the modified Rankin Scale (mRS) at 3 months. Influence of the SVD subtype of stroke was analyzed using Kaplan-Meier log-rank analysis with endpoint all-cause death, and Cox regression proportional hazards model was constructed for multivariate analysis. The association between SVD and causes of death (cardiac, brain-related, all other) was analyzed using Kaplan-Meier log-rank analysis. RESULTS: Of the 486 patients, stroke etiology was SVD in 63 patients (13.0%). Median survival was 4.3 years for SVD and 7.9 years for non-SVD (p ≤ 0.001). In the stepwise Cox regression analysis adjusted for relevant confounders, independent predictors of death were SVD (hazard ratio [HR] 1.60, 95% confidence interval [CI] 1.06-2.41), advanced age (HR 1.07, 95% CI 1.05-1.09), stroke severity (mRS 3-5 vs 1-2; HR 2.02, 95% CI 1.58-2.58), smoking (HR 1.44, 95% CI 1.10-1.88), and cardiac failure (HR 1.53, 95% CI 1.14-2.06). SVD was associated with cardiac cause of death (p = 0.021). CONCLUSIONS: In this well-characterized ischemic stroke cohort of patients aged 55-85 years with a 12-year follow-up, acute index stroke attributable to SVD was associated with poorer long-term survival and higher risk for cardiac death than other stroke subtypes.

Exercise training and experimental diabetes modulate heat shock protein response in brain.

In diabetes, defense systems against cellular stress are impaired. Heat shock proteins (HSPs) function primarily as molecular chaperones. Factors that raise tissue HSP levels may slow progression of diabetes and improve diabetic complications that also affect brain tissue. This study tested the effect of an 8-week exercise training on brain HSP response in rats with or without streptozotocin-induced diabetes (SID). In untrained animals, the HSP levels were not different between SID and non-diabetic groups. Endurance training, however, increased HSP72 and HSP90 protein in non-diabetic rats, whereas SID significantly decreased the effect of training on these HSPs. At the mRNA level, HSP60, HSP90 and GRP75 were increased due to training, whereas HSP72 mRNA was only increased in exercise-trained diabetic animals. Training or diabetes had no effect on protein carbonyl content, a marker of oxidative damage. Altogether, our findings suggest that endurance training increases HSP expression in the brain, and that experimental diabetes is associated with an incomplete HSP response at the protein level.

Modified ankle-brachial index detects more patients at risk in a Finnish primary health care.

OBJECTIVES: Despite peripheral arterial disease (PAD), defined as ankle-brachial index (ABI)or=70 years or calf pain during exercise. A total of 817 patients were recruited. METHODS: Research methods included interview and Doppler measurement of brachial and ankle pressures. RESULTS: An ABI(mod)or=1.4 had the strongest association with CVD. CONCLUSIONS: PAD is highly prevalent among patients presenting to primary care. ABI(mod) calculation detects more number of patients at risk at the cost of reduced specificity. The association of high ABI with CVD noted in this study warrants future research for validation.

Cognitive impairment predicts poststroke death in long-term follow-up.

BACKGROUND: Poststroke global cognitive decline and dementia have been related to poor long-term survival. Whether deficits in specific cognitive domains are associated with long-term survival in patients with ischaemic stroke is not known in detail. METHODS: Patients with acute stroke subjected to comprehensive neuropsychological evaluation were included in the study (n = 409) and followed up for up to 12 years. RESULTS: In Kaplan-Meier analysis, impairments in following cognitive domains predicted poor poststroke survival (estimated years): executive functions (48.2%) (5.8 vs 10.1 years, p<0.0001), memory (59.9%) (6.8 vs 9.3 years, p = 0.009), language (28.9%) (5.3 vs 8.6 years, p = 0.004) and visuospatial/constructional abilities (55.2%) (5.6 vs 10.1 years, p<0.0001). Low Mini Mental Status Examination (MMSE)

Poststroke dementia predicts poor survival in long-term follow-up: influence of prestroke cognitive decline and previous stroke.

BACKGROUND: The aim of this study was to investigate the influence of poststroke dementia on long-term survival after acute stroke and also to assess the possible influence of prestroke cognitive decline and previous stroke on this relationship. METHODS: A total of 451 consecutive patients with acute ischaemic stroke admitted to hospital were included in the study and followed up for 12 years. Dementia was diagnosed 3 months after stroke in 115 patients (25.5%). RESULTS: In Kaplan-Meier analysis, poststroke dementia predicted poor long-term survival (5.1 years vs 8.8 years in patients who did not have poststroke dementia; p<0.001). Prestroke cognitive decline had a negative influence on survival in patients with poststroke dementia (3.8 years vs 5.8 years; p<0.001); however, previous stroke did not affect survival in these patients (p = 0.676). In stepwise Cox regression proportional hazards analysis adjusted for significant covariates, poststroke dementia (hazard ratio (HR) 1.53; p = 0.003), advanced age (HR 1.07; p<0.001), severity of stroke (HR 1.91; p<0.001), smoking (HR 1.35; p = 0.035), cardiac failure (HR 1.61; p = 0.003) and atrial fibrillation (HR 1.89; p = 0.035) were all independent predictors of poor long-term survival. Poststroke dementia (HR 2.33; p<0.001), advanced age (HR 1.07; p<0.001) and poor Rankin score (HR 2.15; p = 0.001) were associated with death from brain-related causes, including infarction, haemorrhage and dementia. CONCLUSIONS: Long-term follow-up of our large well-defined poststroke cohort indicated that in patients with acute stroke, dementia is a significant predictor of poor long-term survival and death from brain-associated causes. Prestroke cognitive decline seems to have an additional negative influence on survival, but previous stroke does not seem to affect survival.

Age related white matter changes predict stroke death in long term follow-up.

OBJECTIVE: Recurrent strokes and functional decline are predicted by age related white matter changes (ARWMC). Whether they are associated with long term survival among hospital patients referred for acute stroke is not known. METHODS: A total of 396 consecutive acute stroke patients subjected to MRI were included in the study and followed-up for up to 12 years. RESULTS: 28% had mild, 18% had moderate and 54% had severe ARWMCs. In Kaplan-Meier analysis, poor survival was predicted by severe ARWMCs (p<0.0001), cardiac failure (CF, p<0.0001), atrial fibrillation (AF, p<0.0001), other arrhythmias (p = 0.003), peripheral arterial disease (PAD, p = 0.004) and poor modified Rankin score (mRS) (p<0.0001). ARWMC was related to death by all brain related causes, especially ischaemic stroke (p<0.0001). In stepwise Cox regression analysis adjusted with significant risk factors, severe ARWMCs (hazard ratio (HR) 1.34, 95% CI 1.03 to 1.73; p = 0.029), age (HR 1.07, 95% CI 1.05 to 1.09; p<0.0001), CF (HR 1.59, 95% CI 1.17 to 2.15; p = 0.003), AF (HR 1.68, 95% CI 1.24 to 2.27; p = 0.001), PAD (HR 1.59, 95% CI 1.11 to 2.26; p = 0.011), diabetes (HR 1.44, 95% CI 1.08 to 1.92; p = 0.013), smoking (HR 1.60, 95% CI 1.23 to 2.08; p<0.0001) and mRS (HR 1.65, 95% CI 1.26 to 2.14; p<0.0001) were independently associated with death from all causes. Severe ARWMCs (HR 1.80, 95% CI 1.10 to 2.96; p = 0.019), age (HR 1.05, 95% CI 1.01 to 1.09; p = 0.009), AF (HR 1.82, 95% CI 1.08 to 3.07; p = 0.026), PAD (HR 2.17, 95% CI 1.19 to 3.95; p = 0.012) and mRS (HR 2.75, 95% CI 1.67 to 4.54; p<0.0001) were specifically associated with death from brain related causes. CONCLUSIONS: In patients with acute stroke, ARWMC seems to be a significant predictor of poor long term survival and death by ischaemic stroke.

Long-term survival after ischemic stroke in postmenopausal women is affected by an interaction between smoking and genetic variation in nitric oxide synthases.

BACKGROUND: We aimed to study whether variations in vasoregulatory endothelial nitric oxide synthase (eNOS 4a/b) and tissue-injury-associated inducible nitric oxide synthase (iNOS R5/4) genes and smoking might explain gender differences in long-term survival after stroke. METHODS: A total of 486 consecutive acute stroke patients, subjected to MRI, were followed up for a mean of 7.6 years. The eNOS 4a/b (n = 300) and iNOS R5/4 (n = 310) genotypes were determined by PCR. Of these patients, 213/300 (71.0%; eNOS 4a/b) and 223/310 (71.9%; iNOS R5/4) had died. RESULTS: Despite the fact that women were older than men (72.3 vs. 69.5 years, p = 0.001) at recruitment, poor long-term survival was not sex-related, but instead predicted by age (p < 0.0001), cardiac failure (p = 0.004), smoking (p = 0.017), diabetes (p = 0.049), and variation in the eNOS gene locus (p = 0.033). Smoking and variations in both eNOS [hazard ratio (HR) = 1.53, p = 0.011] and iNOS loci (HR = 1.52, p = 0.073) were found to impact upon poor survival. We found a strong interaction between smoking, female sex, and the iNOS R5/4 genotype with the risk of death (HR = 3.23, CI = 1.51-6.90, p = 0.002). Compared with nonsmoking noncarriers, postmenopausal women who had been smokers and carried either the rare iNOS R5 allele (17.1%; HR = 4.23, CI = 1.84-9.75, p = 0.001) or the common eNOS 4b allele (71%; HR = 3.14, CI = 1.49-6.62, p = 0.003) were at a higher risk of death during the follow-up. These interactions were independent of each other, and were not found among men. CONCLUSIONS: The interaction between smoking and genetic variants of eNOS and iNOS predicts survival after stroke, especially among postmenopausal women.

Surgery for peptic ulcer today. A study on the incidence, methods and mortality in surgery for peptic ulcer in Finland between 1987 and 1999.

BACKGROUND: During the past 20 years medical therapy of peptic ulcer disease (PUD) has dramatically improved. Simultaneously there has been a significant improvement in living and dietary habits. Quite presumably, all these significant events are reflected in the incidence and results of surgery for peptic ulcerations. AIM: To study the incidence, methods and mortality of surgery for PUD. METHODS: The nationwide data between 1987 and 1999 were obtained from the National Research and Development Centre for Welfare and Health. In the analysis the codes of the ICD 9-10 were used. RESULTS: The annual incidence of elective surgery for PUD decreased from 15.7 to 1.7 operations (per 10(5) inhabitants, mean of 2 consecutive years) between 1987 and 1999 (p < 0.05). Simultaneously, the annual incidence of emergency surgery increased from 5.2 to 7.0 operations (per 10(5) inhabitants, p < 0.05). In 1987, local procedures (duodeno-/gastrorrhaphy or duodeno-/gastrostomy and suture) were applied in 25% of operations for PUD, whereas in 1999 they were 90% of the methods in PUD surgery. The overall annual mortality from PUD surgery remained 8% between 1987 and 1999. CONCLUSIONS: Elective ulcer surgery has virtually disappeared and parietal cell vagotomy has become history, whereas the incidence of emergency surgery increased significantly between 1987 and 2000, with the exception of the most recent years. Local procedures are overwhelmingly applied in emergency surgery and more extensive surgery is unnecessary. Nevertheless, the overall surgical mortality remained 8% between 1987 and 1999.

Reperfusion but not acute ischemia in pig small intestine induces transcriptionally mediated heat shock response in situ.

BACKGROUND: Although there is data on the cytoprotective role of heat shock proteins in intestinal ischemia-reperfusion, the effects of ischemia and reperfusion per se on the small intestinal heat shock response have been poorly characterized. METHODS: Four female pigs were subjected to 60-min ischemia by superior mesenteric artery occlusion followed by 360-min reperfusion. Systemic and local hemodynamics were monitored. Samples from the jejunal mucosa and muscularis were obtained for histology and for time series molecular biologic analyses of heat shock transcription factor 1 (HSF1), hsp70 mRNA and Hsp70 protein. RESULTS: A 30-min reperfusion of jejunum after a preceding 1-hour ischemia results in a significantly increased DNA-binding activity of HSF1, in a 10-fold increase of hsp70 mRNA in the mucosal and in a 7-fold increase in the muscular layers. Translational activation and accumulation of Hsp70 protein occurs after 60 min of reperfusion in the intestine. Nevertheless, a 60-min ischemia inducing mucosal detachment does not induce the heat shock response at any level analyzed. CONCLUSIONS: Ischemia alone is insufficient to induce the heat shock response, whereas subsequent reperfusion induces the response via transcriptionally mediated induction of Hsp70 synthesis both in the mucosal and muscular layers.

Preconditioning hyperthermia inhibits restitution of isolated Guinea pig gastric mucosa.

BACKGROUND: Superficial epithelial injury is followed by restitution which is based on the migration of the surviving mucosal cells to restore the disturbed epithelial continuity. There is previous data that heat-shock (HS) preconditioning may be utilized to enhance the tissue tolerance to injury. Yet, there is little data about the effect of preconditioning on restitution. METHODS: Guinea pig gastric mucosae were mounted and perfused in Ussing chambers. After stabilization, a HS (42 degrees C, 30 min) and concomitant heat-shock protein (Hsp) production was induced. After stabilization and reaching the normothermia, a superficial injury (1.25 mol/l NaCl) was induced. Subsequently, the tissue was allowed to restitute for 3 h. In some sets of experiments, protein synthesis was inhibited either with quercetin or with cycloheximide. During the experiment, transmucosal electrophysiological resistance (R) of the tissue was recorded. After the experiment, the mucosa was prepared for morphologic analysis and for Western blot. RESULTS: HS did not affect mucosal tolerance to hyperosmolar injury, but inhibited significantly restitution after injury and upregulated Hsp70 as well. The levels of Hsp70 correlated inversely with recovery of R and histology. Quercetin and cycloheximide abolished this effect of HS, while quercetin did not completely abolish Hsp70 upregulation. CONCLUSION: Hyperthermic preconditioning inhibits the restitution of gastrointestinal mucosa in correlation with Hsp70 levels. The inhibition of restitution is sensitive to blockades of de novo protein synthesis and of Hsp70 production.

Heat-shock preconditioning affects restitution of isolated guinea pig gastric mucosa by an arachidonic acid and protein synthesis dependent mechanism.

BACKGROUND: Superficial mucosal injury is repaired immediately by a process known as restitution, which is controlled by several factors and is based on cellular migration. Heat-shock preconditioning increases the tolerance of tissue to deep gastric mucosal injury via synthesis of heat-shock proteins. Despite immediate positive effects on the tissue, we have shown that heat-shock preconditioning inhibits restitution of gastric mucosa after subsequent superficial injury in correlation with Hsp70 levels. In addition to heat-shock proteins, heat preconditioning is known to affect eicosanoid pathways. In this study, we explore the role of eicosanoid pathways and protein synthesis in heat-shock-induced inhibition of restitution. METHODS: Guinea pig gastric mucosa was mounted and perfused in a Ussing chamber (37 degrees C). After heat-shock preconditioning (HS) (42 degrees C) and normothermic recovery, a superficial injury was induced (1.25 mol/L NaCl) followed by a 3-h restitution. Transmucosal electrophysiologic resistance of the tissue (R) was recorded during the experiment. During perfusion, the mucosa was exposed to 30 micromol/L arachidonic acid as a substrate for eicosanoid pathways; 50 micromol/L quercetin to inhibit the metabolism of arachidonic acid via lipoxygenases, 50 micromol/L indomethacin to inhibit the metabolism of arachidonic acid via cyclo-oxygenases, or 150 micromol/L cycloheximide to inhibit de novo protein synthesis. After the experiment, the mucosa was prepared for morphologic analysis and Western blotting. RESULTS: HS inhibited restitution after NaCl insult and upregulated Hsp70. Exposure of the tissue to quercetin, cycloheximide, arachidonic acid, or to indomethacin overcame the inhibitory effect of HS, which could be pronounced by simultaneous indomethacin and quercetin augmenting expression of Hsp70. CONCLUSION: HS preconditioning inhibits restitution by a mechanism that involves arachidonic acid metabolism and de novo protein synthesis.