Long-term alcohol consumption increases matrix metalloproteinase-2 activity in rat aorta

Longitudinal Associations between Alcohol Intake and Arterial Stiffness, Pressure Wave Reflection, and Inflammation

AIMS

This prospective observational study, which utilized repeated annual measurements performed over a 9-year period, applied mixed model analyses to examine age-related differences in longitudinal associations between alcohol intake and arterial stiffness, pressure wave reflection, and inflammation.

METHODS

In 4016 middle-aged (43±9 years) healthy Japanese male employees, alcohol intake, brachial-ankle pulse wave velocity (baPWV), radial augmentation index (rAI), and serum C-reactive protein (CRP) levels were measured annually during a 9-year study period.

RESULTS

The estimated marginal mean baPWV (non-drinkers=1306 cm/s, mild-moderate drinkers=1311 cm/s, and heavy drinkers=1337 cm/s, P＜0.01) and that of rAI showed significant stepped increases in an alcohol dose-dependent manner in the entire cohort, but an increase in rAI was not observed in subjects aged ≥ 50 years. The estimated slope of the annual increase in baPWV, but not rAI, was higher for heavy drinkers than for non-drinkers (slope difference, 1.84; P＜0.05), especially for subjects aged ＜50 years (slope difference, 2.84; P＜0.05).

CONCLUSION

In middle-aged male Japanese employees, alcohol intake may attenuate inflammatory activity. While alcohol intake may exacerbate the progression of arterial stiffening in a dose-dependent manner without mediating inflammation, especially in subjects under 50 years of age, it may promote pressure wave reflection abnormalities with aging at earlier ages without further exacerbation at older ages.

Optimal lifestyle behaviors and 10-year progression of arterial stiffness: The multi-ethnic study of atherosclerosis

Majority of previous studies showed no association between a single health behavior and arterial stiffness, but the benefit of simultaneously having multiple healthy behaviors (optimal lifestyle) on the progression of arterial stiffness is unknown. Among 2810 individuals (age 60.0 ± 9.4, 46.5% male), optimal lifestyle marker (yes/no) on four health behaviors (ie, BMI < 25 kg/m², never or former smoker, never or moderate drinker, exercised > 500 METS min/week) across four visits (≈ 5 years) were summed to create an optimal lifestyle score. Carotid arterial stiffness was measured using distensibility coefficient (DC) and Young's elastic modulus (YEM) at visit 1 and after a mean of 9.5 years (visit 5). The association of optimal lifestyle with 10‐year percent change in DC and YEM was assessed using multiple linear regression. DC decreased by 5.3% and YEM increased by 24.4% over 10 years. Mean optimal lifestyle score was 9.4 ± 3.1 (range: 0–16). Individuals in quintiles 2–5 of optimal lifestyle score compared to quintile 1 (with the least optimal lifestyle score) did not show slower deceleration of DC [Q2, −0.3% (95% CI: −6.0, 5.4); Q3, −0.01% (−4.5, 4.5); Q4, −0.6% (−5.2, 3.9); Q5, −0.4% (−5.3, 4.4)], trend p‐value = .82] or slower progression of YEM [Q2, 0.1% (−7.1, 7.3); Q3, −0.8% (−8.0, 6.5); Q4, 4.5% (−2.3, 11.3); Q5, −0.2% (−8.3, 7.9)], trend p‐value = .49] after adjusting for risk factors. The association remained non‐significant when stratified by categories of age, sex, race, BP control, and diabetes. Our findings indicate that optimal score on multiple health behaviors may not independently slow arterial stiffness progression.

In Vivo Study of Nasal Bone Reconstruction with Collagen, Elastin and Chitosan Membranes in Abstainer and Alcoholic Rats

The aim of the present study was to evaluate the use of collagen, elastin, or chitosan biomaterial for bone reconstruction in rats submitted or not to experimental alcoholism. Wistar male rats were divided into eight groups, submitted to chronic alcohol ingestion (G5 to G8) or not (G1 to G4). Nasal bone defects were filled with clot in animals of G1 and G5 and with collagen, elastin, and chitosan grafts in G2/G6, G3/G7, and G4/G8, respectively. Six weeks after, all specimens underwent radiographic, tomographic, and microscopic evaluations. Bone mineral density was lower in the defect area in alcoholic animals compared to the abstainer animals. Bone neoformation was greater in the abstainer groups receiving the elastin membrane and in abstainer and alcoholic rats receiving the chitosan membrane (15.78 ± 1.19, 27.81 ± 0.91, 47.29 ± 0.97, 42.69 ± 1.52, 13.81 ± 1.60, 18.59 ± 1.37, 16.54 ± 0.89, and 37.06 ± 1.17 in G1 to G8, respectively). In conclusion, osteogenesis and bone density were more expressive after the application of the elastin matrix in abstainer animals and of the chitosan matrix in both abstainer and alcoholic animals. Chronic alcohol ingestion resulted in lower bone formation and greater formation of fibrous connective tissue.

Association between abdominal aortic aneurysms and alcohol-related diseases

Heterogeneous associations exist between alcohol consumption and the initial presentation of cardiovascular diseases (CVDs). Studies regarding the association between abdominal aortic aneurysms (AAAs) and alcohol consumption are still limited and controversial. We hypothesize that patients with alcohol-related diseases are susceptible to AAA formation due to the presence of overlapping epidemiological factors and molecular mechanisms. We aimed to use a nationwide population-based retrospective cohort study to evaluate the association between alcohol-related diseases and AAA.The data were extracted from the National Health Insurance Research Database (NHIRD) in Taiwan. The study outcome assessed was the cumulative incidence of AAA in patients with alcohol-related diseases during a 14-year follow-up period.Our study included 22,878 patients who had alcohol-related diseases; these patients with alcohol-related diseases had a significantly higher cumulative risk of developing AAA 5 years after the index date than did the 91,512 patients without alcohol-related diseases. Patients with alcohol-related diseases also exhibited a significantly increased incidence of AAA compared with the incidence among patients without alcohol-related diseases, according to Cox regression analysis and Fine & Gray's competing risk model (adjusted hazard ratio = 2.379, 95% confidence interval = 1.653 -3.424, P < .001). In addition, male gender, older age, and chronic kidney disease were also associated with an increased risk of developing AAA. An interaction model showed that males with alcohol-related diseases had a 10.4-fold higher risk of AAA than did females without alcohol-related diseases.We observed an association between alcohol-related diseases and AAA even after adjusting for several comorbidities and medications in a nationwide population database.

Cerebral embolization associated with parenchymal seeding of the left atrial myxoma: Potential role of interleukin-6 and matrix metalloproteinases

Systemic embolization has been reported in up to 40% of patients with left atrial myxoma, half of them with cerebral involvement. However, development of intracerebral embolization associated with parenchymal seeding of the myxoma emboli is an extremely rare complication, with only 36 histologically diagnosed cases reported in the published literature. We describe a 69-year-old woman who arrived at the emergency service with hemiparesis associated with drug-resistant epilepsy and a medical history of resection of a left atrial myxoma 10 months previously. Cranial computed tomography revealed multiple large lesions of heterogeneous density and cystic components in the occipital lobes and posterior fossa parenchyma. Histopathological analyses after stereotactic biopsy of the occipital lesion revealed infiltrative myxoma cells with benign histological findings and uniform expression of calretinin similar to that of the primary cardiac myxoma. Additional immunohistochemical studies confirmed brain parenchymal seeding of the myxoma cells with strong expression of interleukin-6 (IL-6) and focal expression of matrix metalloproteinases-2 (MMP-2). Here, we discuss the clinicopathological features of intracerebral embolization of left atrial myxomas associated with progressive parenchymal seeding of the tumor emboli and the potential pathogenic role of IL-6 and MMPs.

Alcohol Consumption and Aortic Root Dilatation: Insights from the Corinthia Study

Aortic diameter and progression to thoracic aortic aneurysm are influenced by several factors. In this study, we investigated the association of alcohol consumption with aortic root and ascending aorta dilatation. In the context of the Corinthia study, we examined 1751 patients with echocardiography. Several demographic and clinical characteristics were recorded. Alcohol consumption was assessed based on a questionnaire of frequency, type, and quantity. Accordingly, patients were categorized as everyday alcohol consumers (EDACs) and as social drinkers (SoD). Everyday alcohol consumers were further categorized to group 1: 0 to 1 drink/d; group 2: 1 to 2 drinks/d; and group 3: ≥3 drinks/d. From the study population, 40% were categorized as EDAC and had an increased aortic root diameter (AoRD) and an elevated AoRD index compared with SoD. Interestingly, there was a stepwise increase in aortic root and ascending aorta diameter according to daily alcohol consumption. Specifically, patients consuming ≥3 drinks of alcohol/d had increased indexed aortic by 1.4 mm/m2 compared with SoD even after adjustment for possible confounders. Daily alcohol consumption is associated with increased aortic root diameter. These findings may have important clinical implications, especially in patients with borderline or dilated aortic root, and merit further investigation.

Genetic Contribution to Initial and Progressive Alcohol Intake Among Recombinant Inbred Strains of Mice

We profiled individual differences in alcohol consumption upon initial exposure and during 5 weeks of voluntary alcohol intake in female mice from 39 BXD recombinant inbred strains and parents using the drinking in the dark (DID) method. In this paradigm, a single bottle of 20% (v/v) alcohol was presented as the sole liquid source for 2 or 4 h starting 3 h into the dark cycle. For 3 consecutive days mice had access to alcohol for 2 h followed by a 4th day of 4 h access and 3 intervening days where alcohol was not offered. We followed this regime for 5 weeks. For most strains, 2 or 4 h alcohol intake increased over the 5-week period, with some strains demonstrating greatly increased intake. There was considerable and heritable genetic variation in alcohol consumption upon initial early and sustained weekly exposure. Two different mapping algorithms were used to identify QTLs associated with alcohol intake and only QTLs detected by both methods were considered further. Multiple suggestive QTLs for alcohol intake on chromosomes (Chrs) 2, 6, and 12 were identified for the first 4 h exposure. Suggestive QTLs for sustained intake during later weeks were identified on Chrs 4 and 8. Thirty high priority candidate genes, including Entpd2, Per3, and Fto were nominated for early and sustained alcohol intake QTLs. In addition, a suggestive QTL on Chr 15 was detected for change in 2 h alcohol intake over the duration of the study and Adcy8 was identified as a strong candidate gene. Bioinformatic analyses revealed that early and sustained alcohol intake is likely driven by genes and pathways involved in signaling, and/or immune and metabolic function, while a combination of epigenetic factors related to alcohol experience and genetic factors likely drives progressive alcohol intake.

Meta-analysis of the association between alcohol consumption and abdominal aortic aneurysm

Background

Alcohol is a possible risk factor for abdominal aortic aneurysm (AAA), but evidence from individual studies is weak and inconsistent. Existing narrative reviews suggest the possibility of non-linear associations. The aim here was to quantify any association using a systematic literature review, followed by dose–response meta-analysis of prospective studies.

Methods

MEDLINE, Embase and Web of Science were searched systematically to January 2017 for relevant prospective studies of alcohol consumption and AAA risk. Summary estimates of highest versus lowest levels of consumption, and linear and non-linear dose–response curves were quantified using random-effects models.

Results

Eleven relevant cohorts were identified describing results from 3580 individuals with among 473 092 participants. Data were extracted from ten cohorts for meta-analyses of high versus low levels of alcohol consumption (risk ratio for AAA 0·93, 95 per cent c.i. 0·78 to 1·11; P = 0·4, I2 = 47 per cent). The linear dose–response risk ratio for AAA, derived from 11 cohorts, was 1·00 (0·97 to 1·04) per 8 g alcohol per day (P = 0·9, I2 = 73 per cent). Non-linear dose–response results showed a tick-shaped curve with lower risk up to 2 units/day, but increasing risk beyond that (P = 0·05). The increase in risk beyond 2 units/day was stronger in men than in women.

Conclusion

Although the linear dose–response analysis revealed little evidence of an association between alcohol consumption and AAA risk, a tick-shaped trend in the association was observed. This non-linear dose–response analysis revealed reduced risks for alcohol consumption below 2 units/day, masking increased risks for 2 or more units/day.

Dysregulated mitogen-activated protein kinase and matrix metalloproteinase in ethanol-induced cavernosal dysfunction

We evaluated the effects of ethanol consumption on the mitogen-activated protein kinases (MAPK) and metalloproteinases (MMP) pathways in the rat cavernosal smooth muscle (CSM). Male Wistar rats were treated with ethanol (20% v/v) for 6 weeks. Quantitative real-time polymerase chain reaction experiments showed that ethanol consumption did not alter mRNA levels of p38MAPK, SAPK/JNK, ERK1/2, MMP-2, or MMP-9 in the rat CSM. Western immunoblotting experiments revealed decreased protein expression of p38MAPK and phosphorylation of SAPK/JNK in the CSM from ethanol-treated rats. Additionally, ethanol consumption decreased the expression of MMP-2. Functional assays showed that SP600125, an inhibitor of SAPK/JNK, prevented the increase in endothelin (ET)-1-induced contraction in the CSM from ethanol-treated rats. Treatment with ethanol decreased MMP-2 activity, but did not change net MMP activity in the rat CSM. Ethanol consumption increased the circulating levels of MMP-2, MMP-9, and TIMP-2 as well as the MMP-9/TIMP-1 ratio. The major finding of our study is that ethanol consumption down-regulates both MAPK and MMP pathways in the rat CSM, whereas it increases the circulating levels of MMP-9. Additionally, we found that SAPK/JNK plays a role in ethanol-induced increase on ET-1 contraction in the isolated rat CSM.

Chronic ethanol consumption reduces adrenomedullin-induced relaxation in the isolated rat aorta

Adrenomedullin (AM) is a peptide that displays cardiovascular protective activity. We investigated the effects of chronic ethanol consumption on vascular reactivity to AM and the expression of AM system components in the rat aorta. Male Wistar rats were treated with ethanol (20% vol/vol) for 6 weeks. Vascular reactivity experiments were performed in the isolated rat aorta. Metalloproteinase-2 (MMP-2) levels were determined by gelatin zymography. Nitrite and nitrate generation was measured by chemiluminescence. Protein and mRNA levels of pre-pro-AM, calcitonin receptor-like receptor (CRLR) and RAMP1, 2, and 3 (receptor-activity-modifying proteins) were assessed by western blot and quantitative real-time polymerase chain reaction, respectively. Ethanol intake reduced AM-induced relaxation in endothelium-intact rat aortas, whereas calcitonin gene-related peptide-, acetylcholine-, and sodium nitroprusside-induced relaxation were not affected by ethanol intake. N(G)-nitro-l-arginine-methyl-ester (l-NAME), 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, and tetraethylammonium reduced AM-induced relaxation in aortic rings from both control and ethanol-treated rats. Ethanol consumption did not alter basal levels of nitrate and nitrite, nor did it affect the expression of MMP-2 in the rat aorta. Ethanol consumption increased mRNA levels of pre-pro-AM and RAMP1. Protein levels of AM, CRLR, and RAMP1, 2, and 3 were not affected by ethanol consumption. The major findings of the present study are that ethanol consumption reduces the vascular relaxation induced by AM and changes the mRNA expression of the components of the AM system in the vasculature. This response could be one of the mechanisms by which ethanol predisposes individuals to vascular dysfunction and hypertension.

Ethanol consumption increases the expression of endothelial nitric oxide synthase, inducible nitric oxide synthase and metalloproteinases in the rat kidney

Objectives

The effects of longterm ethanol consumption on the levels of nitric oxide (NO) and the expression of endothelial NO synthase (eNOS), inducible NO synthase (iNOS) and metalloproteinase-2 (MMP-2) were studied in rat kidney.

Methods

Male Wistar rats were treated with 20% ethanol (v/v) for 6 weeks. Nitrite and nitrate generation was measured by chemiluminescence. Protein and mRNA levels of eNOS and iNOS were assessed by immunohistochemistry and quantitative real-time polymerase chain reaction, respectively. MMP-2 activity was determined by gelatin zymography. Histopathological changes in kidneys and indices of renal function (creatinine and urea) and tissue injury (mitochondrial respiration) were also investigated.

Results

Chronic ethanol consumption did not alter malondialdehyde levels in the kidney. Ethanol consumption induced a significant increase in renal nitrite and nitrate levels. Treatment with ethanol increased mRNA expression of both eNOS and iNOS. Immunohistochemical assays showed increased immunostaining for eNOS and iNOS after treatment with ethanol. Kidneys from ethanol-treated rats showed increased activity of MMP-2. Histopathological investigation of kidneys from ethanol-treated animals revealed tubular necrosis. Indices of renal function and tissue injury were not altered in ethanol-treated rats.

Conclusions

Ethanol consumption increased renal metalloproteinase expression/activity, which was accompanied by histopathological changes in the kidney and elevated NO generation. Since iNOS-derived NO and MMPs contribute to progressive renal injury, the increased levels of NO and MMPs observed in ethanol-treated rats might contribute to progressive renal damage.

Ethanol consumption alters the expression and reactivity of adrenomedullin in the rat mesenteric arterial bed

AIMS

Adrenomedullin (AM) is a peptide that displays cardiovascular protective activity. We investigated the effects of chronic ethanol consumption on arterial blood pressure, vascular reactivity to AM and the expression of AM system components in the rat mesenteric arterial bed (MAB).

METHODS

Male Wistar rats were treated with ethanol (20% vol/vol) for 6 weeks. Systolic, diastolic and mean arterial blood pressure were monitored in conscious rats. Vascular reactivity experiments were performed on isolated rat MAB. Matrix metalloproteinase-2 (MMP-2) levels were determined by gelatin zymography. Nitrite and nitrate generation were measured by chemiluminescence. Protein and mRNA levels of pre-pro-AM, CRLR (calcitonin receptor-like receptor) and RAMP1, 2 and 3 (receptor activity-modifying proteins) were assessed by western blot and quantitative real-time polymerase chain reaction, respectively.

RESULTS

Ethanol consumption induced hypertension and decreased the relaxation induced by AM and acetylcholine in endothelium-intact rat MAB. Phenylephrine-induced contraction was increased in endothelium-intact MAB from ethanol-treated rats. Ethanol consumption did not alter basal levels of nitrate and nitrite, nor did it affect the expression of MMP-2 or the net MMP activity in the rat MAB. Ethanol consumption increased mRNA levels of pre-pro-AM and protein levels of AM in the rat MAB. Finally, no differences in protein levels or mRNA of CRLR and RAMP1, 2 and 3 were observed after treatment with ethanol.

CONCLUSION

Our study demonstrates that ethanol consumption increases blood pressure and the expression of AM in the vasculature and reduces the relaxation induced by this peptide in the rat MAB.

Altered hepatic lipid metabolism in C57BL/6 mice fed alcohol: a targeted lipidomic and gene expression study

Chronic alcohol consumption is associated with fatty liver disease in mammals. The object of this study was to gain an understanding of dysregulated lipid metabolism in alcohol-fed C57BL/6 mice using a targeted lipidomic approach. Liquid chromatography tandem mass spectrometry was used to analyze several lipid classes, including free fatty acids, fatty acyl-CoAs, fatty acid ethyl esters, sphingolipids, ceramides, and endocannabinoids, in plasma and liver samples from control and alcohol-fed mice. The interpretation of lipidomic data was augmented by gene expression analyses for important metabolic enzymes in the lipid pathways studied. Alcohol feeding was associated with i) increased hepatic free fatty acid levels and decreased fatty acyl-CoA levels associated with decreased mitochondrial fatty acid oxidation and decreased fatty acyl-CoA synthesis, respectively; ii) increased hepatic ceramide levels associated with higher levels of the precursor molecules sphingosine and sphinganine; and iii) increased hepatic levels of the endocannabinoid anandamide associated with decreased expression of its catabolic enzyme fatty acid amide hydrolase. The unique combination of lipidomic and gene expression analyses allows for a better mechanistic understanding of dysregulated lipid metabolism in the development of alcoholic fatty liver disease.

Impairment of long-term potentiation in the hippocampus of alcohol-treated OLETF rats

Type 2 diabetes and chronic heavy alcohol consumption each have been known to be associated with the impairment of hippocampus-dependent cognitive functions. Although both conditions often coexist clinically and there is accumulated evidence of a relationship between the two, the combined effect on hippocampal long-term potentiation (LTP) has not yet been investigated. We compared the effect of type 2 diabetes itself with that of type 2 diabetes with chronic heavy alcohol consumption on the hippocampal LTP using Otsuka Long-Evans Tokushima Fatty (OLETF) rat model, which resembles the characteristics of human type 2 diabetes. Ten of 16-week-old male OLETF rats were randomized into two treatment groups according to weight: the OLETF-Alcohol (O-A, n=5) and the OLETF-Control (O-C, n=5). The rats in the O-A group were fed Lieber-DeCarli Regular EtOH over a 10-week period and the amount of alcohol consumption was 8.42±2.52g/kg/day. To ensure the effect of poor glycemic control on LTP, intraperitoneal glucose tolerance test was performed after a 10-week treatment. The hippocampal LTP was measured by extracellular field excitatory post-synaptic potentials at Shaffer collateral (SC) synapses in the CA1 region. Although the O-A group showed significantly lower fasting and postprandial glucose (P<0.01 and P=0.02, respectively), the hippocampal LTP was more significantly attenuated in the O-A group than the O-C group (P=0.032). The results of this study suggested that chronic heavy alcohol consumption could potentiate the impairment of hippocampal LTP in individuals with impaired glucose tolerance or early type 2 diabetes, even though it did not aggravate, but did improve glycemic control. Clinical attention to chronic heavy drinking will be required in preventing cognitive impairment in individuals with type 2 diabetes.

Alcoholism and traumatic subarachnoid hemorrhage: an experimental study on vascular morphology and biomechanics

BACKGROUND

Traumatic subarachnoid hemorrhage (TSAH) related to alcohol abuse is a notable risk factor. Here, we investigated the vascular morphology and biomechanics of TSAH in rat models of acute alcoholic intoxication and chronic alcoholism rats to explore the possible mechanisms of TSAH.

METHODS

Sixty male Sprague-Dawley rats were divided into acute alcoholic intoxication and chronic alcoholism groups. Edible spirituous liquor (56% vol/vol) was intragastrically given (15 mL/kg) once to the rats in the acute group, and given twice daily (8 mL/kg for 2 weeks and 12 mL/kg for another 2 weeks) to rats in the chronic group. A self-made instrument was used to inflict head injury. Whole brain, arterial blood, and thoracic aorta of rats were sampled for morphologic and biomechanical examination.

RESULTS

Compared with the acute alcoholic rats, the chronic alcoholic rats showed significant morphologic and biomechanical changes: (1) decreased body weight (p<0.05), (2) higher morbidity and mortality from TSAH (p<0.01), (3) greater mean thickness of vascular wall of subarachnoid small arteries and each layer thickness of thoracic aorta (p<0.05), (4) decreased failure load and corresponding extensibility (60 kPa and limit load) of thoracic aorta, and (5) increased elastic modulus (30 kPa, range in physiologic stress) (p<0.05).

CONCLUSIONS

Chronic alcoholism can induce the morphologic and biomechanical changes in cerebral vessels and thoracic aorta. The synergistic effect of alcohol abuse and minor blow may be one of the mechanisms of TSAH. High blood pressure from long-term alcohol abuse is also a notable factor.

Pathophysiology and epidemiology of abdominal aortic aneurysms

Abdominal aortic aneurysms (AAAs) are found in up to 8% of men aged >65 years, yet usually remain asymptomatic until they rupture. Rupture of an AAA and its associated catastrophic physiological insult carries overall mortality in excess of 80%, and 2% of all deaths are AAA-related. Pathologically, AAAs are associated with inflammation, smooth muscle cell apoptosis, and matrix degradation. Once thought to be a consequence of advanced atherosclerosis, accruing evidence indicates that AAAs are a focal representation of a systemic disease of the vasculature. Risk factors for AAAs include increasing age, male sex, smoking, and low HDL-cholesterol levels. Familial associations exist and although susceptibility genes have been described on the basis of candidate-gene studies, robust genetic studies have failed to discover causative gene mutations. The surgical management of AAAs has been revolutionized by minimally invasive endovascular repair. Ongoing randomized trials will establish whether endovascular repair confers a survival advantage over open surgery for patients with a ruptured AAA. In many countries, centralization of vascular surgical services has largely been driven by the improved outcomes of elective aneurysm surgery in specialized centers, the widespread adoption of endovascular techniques, and the introduction of screening programs.

Independent determinants of second derivative of the finger photoplethysmogram among various cardiovascular risk factors in middle-aged men

The second derivative of the finger photoplethysmogram (SDPTG) has been used as a non-invasive examination for arterial stiffness. The present study sought to elucidate independent determinants of the SDPTG among various cardiovascular risk factors in middle-aged Japanese men. The SDPTG was obtained from the cuticle of the left-hand forefinger in 973 male workers (mean age: 44+/-6 years) during a medical checkup at a company. The SDPTG indices (b/a and d/a) were calculated from the height of the wave components. Multiple logistic regression analyses revealed that the independent determinants of an increased b/a (highest quartile of the b/a) were age (odds ratio [OR]: 1.12 per 1-year increase, 95% confidence interval [CI]: 1.09-1.15), hypertension (OR: 1.65, 95% CI: 1.03-2.65), dyslipidemia (OR: 1.51, 95% CI: 1.09-2.09), impaired fasting glucose/diabetes mellitus (OR: 2.43, 95% CI: 1.16-5.07), and a lack of regular exercise (OR: 2.00, 95% CI: 1.29-3.08). Similarly, independent determinants of a decreased d/a (lowest quartile of the d/a) were age (OR: 1.11 per 1-year increase, 95% CI: 1.08-1.14), hypertension (OR: 3.44, 95% CI: 2.20-5.38), and alcohol intake 6 or 7 days per week (OR: 2.70, 95% CI: 1.80-4.06). No independent association was observed between the SDPTG indices and blood leukocyte count or serum C-reactive protein levels. In conclusion, the SDPTG indices reflect arterial properties affected by several cardiovascular risk factors in middle-aged Japanese men. The association between inflammation and the SDPTG should be evaluated in further studies.

Alcohol consumption and blood pressure in the adult US population: assessment of gender-related effects

OBJECTIVE

Our objective was to assess the gender-related effects of alcohol consumption on blood pressure (BP) in a representative sample of the adult US population.

METHODS

We examined data from the National Health and Nutrition Examination Survey 1999-2000. The effects of various risk factors for hypertension on BP were examined with analysis of covariance statistics.

RESULTS

Of the 5448 adults over 20 years of age, 2650 (48.7%) reported the intake of one or more drinks per day over the past year. In this population, the mean +/- SEM age was 46.9 +/- 0.34 years, the body mass index was 24.8 kg/m, 1257 (47.4%) were women, systolic BP was 124.3 +/- 0.44 mmHg and diastolic BP was 72.7 +/- 0.27 mmHg. Hypertension was reported in 21.1%, diabetes in 5.1% and cigarette smoking in 39.7%. A significant effect on systolic BP was shown with age (P < 0.01), body mass index (P < 0.01), race (P = 0.01), gender (P < 0.01) and diabetes (P < 0.01). The interaction with gender and alcohol drinking level was significant (P = 0.02). Post-hoc analysis localized the source of this effect. There was a significant increase in systolic BP between one and three and between one and four, but not between one and two, drinks per day in men. This effect was not observed in women.

CONCLUSION

Consistent with previous reports, our study suggests that alcohol intake up to two drinks per day has no effect on BP. There was a gender-related effect of alcohol intake in excess of two drinks per day on BP, with increased BP observed only in men but not in women.

Role of matrix metalloproteinase-2 in ethanol-induced invasion by breast cancer cells

Ethanol is a tumor promoter and may enhance the metastasis of breast cancer. However, the underlying cellular/molecular mechanisms remain unknown. Amplification of ErbB2, a receptor tyrosine kinase, is found in 20-30% of breast cancer patients. Ethanol preferably stimulates invasion by breast cancer cells over-expressing ErbB2 in vitro. Over-expression of ErbB2 is positively associated with elevated levels of matrix metalloproteinase-2 (MMP-2) and MMP-9. Ethanol at physiologically relevant concentrations activates MMP-2 without altering its expression level in mammary epithelial cells over-expressing ErbB2, but not in cells expressing low levels of ErbB2. The activation is dependent on c-jun N-terminal kinases (JNK) and reactive oxygen species. Selective inhibitors of MMP-2 and anti-oxidants significantly inhibit ethanol-stimulated cell invasion. Similarly, knocking down MMP-2 by small interference RNA induces a partial blockage on ethanol-promoted cell invasion. Matrix metalloproteinase-2 is predominantly expressed in stromal fibroblasts; ethanol also activates fibroblastic MMP-2. The conditioned medium collected from ethanol-exposed fibroblasts dramatically stimulates the invasion of breast cancer cells. The role of MMP-2 in ethanol-induced tumor promotion is discussed.

MMP-2 mediates ethanol-induced invasion of mammary epithelial cells over-expressing ErbB2

Ethanol is a tumor promoter and may enhance the metastasis of breast cancer. We have previously demonstrated that over-expression of ErbB2 promoted ethanol-mediated invasion of mammary epithelial cells and breast cancer cells. However, the underlying cellular/molecular mechanisms remain unknown. By gelatin zymography, we showed that over-expression of ErbB2 increased the production of matrix metalloproteinase-2 (MMP-2) and MMP-9 in human mammary epithelial cells (HB2). Transient or stable transfection of ErbB2 cDNA to HB2 cells upregulated the transcripts and the activity of the MMP-2/-9 gene promoter; the upregulation of MMP-2/-9 expression was mediated by p38 mitogen-activated protein kinase (p38 MAPK) and phosphatidylinositol 3-kinase (PI3K). Although ethanol, at physiologically relevant concentrations (100-400 mg/dl), did not affect the production of MMP-2/-9, it activated MMP-2 in HB2 cells over-expressing ErbB2 (HB2(ErbB2)), but not HB2 cells; it enhanced the cleavage of proform MMP-2 (72 kDa) to an active form (62 kDa). The activation was dependent on c-jun N-terminal kinases (JNKs) and reactive oxygen species (ROS). On the other hand, ethanol affected neither the expression nor the activation of MMP-9. Selective inhibitors of MMP-2 (SB-3CT and OA-Hy) and antioxidants significantly inhibited ethanol-stimulated invasion of HB2(ErbB2) cells. Furthermore, knocking down MMP-2 by small interference RNA also induced a partial blockage on ethanol-promoted invasion of HB2(ErbB2) cells. Thus, ethanol-stimulated invasion of cells over-expressing ErbB2 was mediated, at least partially, by MMP-2 activation.

Role of AKT/PKB signaling in fibroblast growth factor-1 (FGF-1)-induced angiogenesis in the chicken chorioallantoic membrane (CAM)

Transfection of chicken chorioallantoic membranes (CAMs) with a chimeric secreted version of fibroblast growth factor-1 (sp-FGF-1) gene construct leads to a significant increase in vascularization. Though FGF-stimulated angiogenesis has been extensively studied, the molecular mechanisms regulating FGF-1-induced angiogenesis are poorly understood in vivo. This study was designed to investigate the role of the AKT (PKB) kinase signaling pathway in mediating sp-FGF-1-induced angiogenesis in the chicken CAM. The involvement of the AKT pathway was demonstrated by up-regulation of AKT1 mRNA expression in sp-FGF-1 compared to vector alone control transfected CAMs as demonstrated by real-time RT-PCR. Western analysis using an antibody specific to the activated AKT (phosphorylated AKT), demonstrated an increase in AKT activity in sp-FGF-1 compared to vector control transfected CAMs. More importantly, the AKT inhibitor ML-9 significantly reduced sp-FGF-1-induced angiogenesis in CAMs. These results indicate that AKT signaling plays a role in FGF-1-stimulated angiogenesis in vivo and the AKT pathway may serve as a therapeutic target for angiogenesis-associated diseases.

Morphological and biomechanical study of abdominal aorta of rats submitted to experimental chronic alcoholism

PURPOSE: To assess the influence of experimental chronic alcoholism in the morphology and biomechanics of the aorta, in a rat model. METHODS: Forty-four Wistar rats were randomly divided into two groups of 22 animals each: in the alcoholism group, the rats received water mixed to increasing concentrations of ethyl alcohol; and control group: the rats received pure water for 180 days. The animals were then killed by an overdose of pentobarbital and the abdominal aortas were excised for histological (hematoxylin-eosin, Masson, Calleja, and Picrosirius red stain), histomorphometrical, and biomechanical analysis. RESULTS: Histology and histomorphometry did not show differences in aorta morphology of both groups. Biomechanical analysis showed a significantly greater yield point elongation in the alcoholic rat group (p<0.05). CONCLUSION: Chronic alcoholism did not cause morphological alterations in the aortic wall but increased elongation, without modifying any other mechanical properties.

Ethanol stimulates the expression of fibronectin in lung fibroblasts via kinase-dependent signals that activate CREB

Ethanol renders the lung susceptible to acute lung injury in the setting of insults such as sepsis. The mechanisms mediating this effect are unknown, but activation of tissue remodeling is considered key to this process. We found that chronic ethanol ingestion in rats increased the expression of fibronectin, a matrix glycoprotein implicated in acute lung injury. In cultured NIH/3T3 cells and in primary rat and mouse lung fibroblasts, ethanol induced fibronectin mRNA and protein expression in a dose- and time-dependent fashion. The effect of ethanol was prevented by inhibitors of protein kinase C and mitogen-activated protein kinases and was associated with the phosphorylation and increased DNA binding of the transcription factor cAMP response element binding protein, followed by increased transcription of the fibronectin gene. Fibroblasts were found to express alpha(7) nicotinic acetylcholine receptor (nAChR), and ethanol induction of fibronectin was abolished by alpha-bungarotoxin and methyllcaconitine, inhibitors of alpha(7) nAChRs. However, ethanol was able to induce fibronectin mRNA and protein in primary lung fibroblasts isolated from alpha(7) nAChR knockout mice. The ethanol-induced fibronectin response was dependent on ethanol metabolism since 4-methylpyrazole, an inhibitor of alcohol dehydrogenase, abolished the effect and acetaldehyde induced it. These observations suggest that ethanol or ethanol metabolites stimulate lung fibroblasts to produce fibronectin by inducing specific signals transmitted via nAChRs independent of the alpha(7-)subunit, and this might represent a mechanism by which ethanol renders the lung susceptible to acute lung injury.

Ethanol-induced in vitro invasion of breast cancer cells: the contribution of MMP-2 by fibroblasts

Ethanol is a tumor promoter and may promote metastasis of breast cancer. However, the underlying cellular/molecular mechanisms remain unknown. Overexpression and high activity of matrix metalloproteinase-2 (MMP-2) are frequently associated with metastatic breast cancers and serve as a prognostic indicator of clinical outcome. MMP-2 is predominantly expressed in stromal fibroblasts and plays a pivotal role in regulating the invasive behavior of breast tumor cells. We hypothesized that ethanol may enhance the invasion of breast tumor cells by modulating the activity of fibroblastic MMP-2. With in vitro models (HS68 and CCD1056SK human fibroblasts), we showed that ethanol at physiologically relevant concentrations (50-200 mg/dl) activated MMP-2; conversely, at a higher concentration (400 mg/dl), it inhibited the MMP-2 activity. Consistently, conditioned medium collected from ethanol (50-200 mg/dl)-exposed fibroblasts markedly enhanced the invasive potential of breast cancer cells and mammary epithelial cells overexpressing ErbB2/HER2 (BT474, SKBR-3 and HB2(ErbB2) cells) but had little effect on cells with low ErbB2 levels (BT20 and HB2 cells). In contrast, conditioned medium obtained from ethanol (400 mg/dl)-treated fibroblasts inhibited cell invasion. Selective inhibitors of MMP-2 (SB-3CT and OA-Hy) eliminated ethanol-stimulated invasion, indicating that the effect of ethanol was mediated by MMP-2. Ethanol activated conventional PKCs and JNKs in fibroblasts; inhibitors of PKC (Go6850 and Go6976) and JNKs (SP600125) significantly inhibited ethanol-mediated MMP-2 activation as well as cell invasion, indicating that PKCs and JNKs play a role in ethanol-induced MMP-2 activation and cell invasion in vitro. Thus, ethanol-promoted breast cancer cell invasion may be mediated by the modulation of fibroblastic MMP-2.

Excessive Alcohol Intake Increases the Risk of Arterial Stiffening in Men with Normal Blood Pressure

Excessive alcohol intake is a known atherosclerotic cardiovascular risk factor. However, the relation between excessive alcohol intake and atherosclerotic cardiovascular risk in subjects with normal blood pressure has not been fully elucidated. This cross-sectional study investigated the relationship between alcohol intake and arterial stiffness, as assessed using brachial-ankle pulse wave velocity, in men with normal blood pressure. Middle-aged male workers who were found to have a normal blood pressure during an annual health check-up performed in May-July 2000 (n=1,682) were enrolled in the study. The subjects' laboratory data were analyzed, and information on drinking and smoking habits was obtained by a self-administered questionnaire. The brachial-ankle pulse wave velocity was measured using volume plethysmography. The mean brachial-ankle pulse wave velocities of men with an alcohol intake of 40-59 g/day and > or =60 g/day were larger than those of non-drinkers and men with an alcohol intake of <20 g/day. A multivariate general linear model was used to identify the association between alcohol intake and brachial-ankle pulse wave velocity after controlling for other risk factors using a multivariate analysis. An alcohol intake of more than 60 g of ethanol/day was significantly associated with an elevated brachial-ankle pulse wave velocity, after controlling for conventional atherosclerotic cardiovascular risk factors. In conclusion, the present results suggest that excessive alcohol intake increases the atherosclerotic cardiovascular risk associated with arterial stiffening in men with normal blood pressure.

Ethanol-induced impairment of spatial memory and brain matrix metalloproteinases

The formation of spatial memory appears to be dependent upon an intact hippocampus capable of the specific biochemical changes associated with synaptic remodeling. Hippocampal damage results in the disruption of synaptic remodeling and the acquisition of spatial memory tasks. Ethanol also disrupts normal hippocampal functioning and spatial memory. The present investigation established a dose-response relationship between ethanol treatment and impairment of spatial memory as measured using the circular water maze task. Intraperitoneal ethanol doses of 1.5 and 2 g/kg significantly increased the latency and distance swam to find the submerged pedestal as compared with a 1 g/kg dose, and 0.15 M NaCl vehicle control treatments. On days 2, 4, and 6 of acquisition animals were sacrificed and brain tissues were retained from the hippocampus, prefrontal neocortex, and cerebellum for measurement of matrix metalloproteinases (MMPs). The results indicated that ethanol treatment interfered with MMP-9, but not MMP-2, activity in the hippocampus, and to a lesser degree in the prefrontal cortex. No changes in the cerebellum were measured. Elevations in MMP activity appear to be a prerequisite to reconfiguration of extracellular matrix cell adhesion molecules thought to be important in the process of synaptic plasticity, which in turn appears to be necessary for memory consolidation. Thus, ethanol-induced impairment in the acquisition of spatial memory tasks may, in part, be due to disruption of brain MMP activity.

Matrix metalloproteinase-9 is elevated in serum of alcohol abusers

BACKGROUND

Moderate alcohol consumption has been shown to protect against coronary heart disease. However, excessive alcohol use has been suggested to have detrimental effects on the cardiovascular system. We examined whether there is an association between alcohol abuse and circulating levels of matrix metalloproteinase-9 (MMP-9), which has been linked to unstable coronary heart disease and arterial inflammation.

DESIGN

Serum MMP-9 concentrations were compared between 40 male alcoholics (mean age 42 years) with ethanol consumption > 1000 g week(-1) and 40 social drinker males with an ethanol consumption of < 200 g week(-1) (mean age 45 years).

RESULTS

The mean serum MMP-9 concentration was significantly higher in sera of alcoholics compared to control subjects (70.9 +/- 47.7 g L(-1) and 43.1 +/- 19.2 g L(-1), respectively; P = 0.001). Within the alcoholic group, MMP-9 concentration did not correlate with age, gamma glutamyl transferase, carbohydrate-deficient transferrin, aspartate aminotransferase, alanine aminotransferase or alkaline phosphatase.

CONCLUSION

Our finding of elevated MMP-9 concentrations in sera of chronic alcohol abusers helps understand the mechanisms of cardiovascular risk among these subjects.

Alcohol consumption and risk for increased aortic pulse wave velocity in middle-aged Japanese men

A 9-year longitudinal study was performed to prospectively examine the association of alcohol consumption with development of increased aortic pulse wave velocity (PWV) in 1,358 Japanese men aged 35 to 59 years with a PWV less than 8.0 m/sec and without antihypertensive medication. Three hundred fifty-nine men developed increased aortic PWV of 8.0 m/sec or more during 10,598 person-years follow-up. After controlling for potential predictors of aortic PWV, the relative risk for increased aortic PWV compared with that in nondrinkers was 1.05 (95% confidence interval [CI], 0.70 to 1.58) for those who drank 0.1 to 22.9 g/day of ethanol, 1.58 (95% CI, 0.89 to 1.91) for those who drank 23.0 to 45.9 g/day of ethanol, 1.77 (95% CI, 1.24 to 2.53) for those who drank 46.0 to 68.9 g/day of ethanol, and 1.81 (95% CI, 1.23 to 2.66) for those who drank 69.0 or more g/day of ethanol (p for trend <0.001). The relative risk for increased aortic PWV in current drinkers vs nondrinkers was stronger among men with a body mass index (BMI) less than 24.2 kg/m2 and nonsmokers than among men with a BMI 24.2 kg/m2 or more and current smokers, respectively. These results suggest that alcohol consumption is closely associated with risk for increased aortic PWV in middle-aged Japanese men.