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1.
Lipids Health Dis ; 20(1): 102, 2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34511125

RESUMO

BACKGROUND: Canola oil (Can) and several vegetable oils shorten the lifespan of stroke-prone spontaneously hypertensive rats (SHRSP). Although similar lifespan shortening has been reported for partially hydrogenated Can, the efficacy of fully hydrogenated oils on the lifespan remains unknown. The present study aimed to investigate the lifespan of SHRSP fed diets containing 10 % (w/w) of fully hydrogenated Can (FHCO) or other oils. METHODS: Survival test: Upon weaning, male SHRSP were fed a basal diet for rodents mixed with one of the test oils -i.e., FHCO, Can, lard (Lrd), and palm oil (Plm) throughout the experiment. The animals could freely access the diet and drinking water (water containing 1 % NaCl), and their body weight, food intake, and lifespan were recorded. Biochemical analysis test: Male SHRSP were fed a test diet with either FHCO, Can, or soybean oil (Soy) under the same condition, except to emphasize effects of fat, that no NaCl loading was applied. Soy was used as a fat source in the basal diet and was set the control group. Blood pressures was checked every 2 weeks, and serum fat levels and histological analyses of the brain and kidney were examined after 7 or 12 weeks of feeding. RESULTS: During the survival study period, the food consumption of FHCO-fed rats significantly increased (15-20 % w/w) compared with that of rats fed any other oil. However, the body weight gain in the FHCO group was significantly less (10-12 %) than that in the control group at 9-11 weeks old. The FHCO (> 180 days) intervention had the greatest effect on lifespan, followed by the Lrd (115 ± 6 days), Plm (101 ± 2 days), and Can (94 ± 3 days) diets. FHCO remarkably decreased the serum cholesterol level compared with Can and the systolic blood pressure from 12 to 16 weeks of age. In addition, while some rats in the Can group exhibited brain hemorrhaging and renal dysfunction at 16 weeks old, no symptoms were observed in the FHCO group. CONCLUSION: This current study suggests that complete hydrogenation decreases the toxicity of Can and even prolongs the lifespan in SHRSP.


Assuntos
Gorduras na Dieta/administração & dosagem , Hipertensão/dietoterapia , Longevidade/efeitos dos fármacos , Óleo de Palmeira/administração & dosagem , Óleo de Brassica napus/administração & dosagem , Óleo de Soja/administração & dosagem , Acidente Vascular Cerebral/prevenção & controle , Animais , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Encéfalo/irrigação sanguínea , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Colesterol/metabolismo , Ingestão de Alimentos/efeitos dos fármacos , Ácidos Graxos/metabolismo , Hidrogenação , Hipertensão/metabolismo , Hipertensão/mortalidade , Hipertensão/fisiopatologia , Rim/irrigação sanguínea , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Fitosteróis/metabolismo , Óleo de Brassica napus/química , Ratos , Ratos Endogâmicos SHR , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/fisiopatologia , Análise de Sobrevida
2.
Pharmacology ; 101(3-4): 184-218, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29353277

RESUMO

BACKGROUND: The Consensus Statement from the European Atherosclerosis Society (EAS) Consensus Panel 2017 concludes on the basis of 3 different types of clinical studies that low-density lipoprotein (LDL) causes atherosclerotic cardiovascular disease (ASCVD). In Mendelian randomization studies, rare genetic mutations affecting LDL receptor function were found to cause higher or lower LDL-C levels, which are associated with correspondingly altered ASCVD risk. In prospective cohort studies and randomized controlled trials (RCTs) of statins, a remarkably consistent log-linear association was demonstrated between the absolute magnitude of LDL-C exposure and ASCVD risk. The EAS Statement proposes that any mechanism of lowering plasma LDL concentration should reduce the risk of ASCVD events proportional to the absolute reduction in LDL-C and the cumulative duration of exposure to lower LDL-C. However, as we explain, we do not find this conclusion acceptable. SUMMARY: Our review points out that different interpretations are possible for the results of Mendelian randomization studies. As for prospective cohort studies, many inconsistent reports on the association of LDL-C and ASCVD were disregarded when drafting the Statement, reports with and without genetic factors related to LDL receptor function should be analyzed separately, and the term ASCVD in the Statement is used inappropriately because myocardial infarction and cerebral infarction differ in their association with LDL-C. As for RCTs, clinical reports on statins published before and after the implementation of new regulations affecting clinical trials (2004/2005) should not both be included in meta-analyses because the evaluated efficacy of statins changed markedly, and the irreversible adverse effects of statins need to be evaluated more rigorously now that their mechanisms have been elucidated. Key Messages: Apart from the EAS hypothesis that LDL causes ASCVD, recent pharmacological/biochemical studies, as summarized in this review and elsewhere, have revealed that atherosclerosis is caused by statins taken to lower LDL-C, as well as by warfarin and some types of vegetable fats and oils, in the absence of significantly elevated LDL-C levels. Thus, the promotion of statin treatment by the Statement is rather risky and we do not feel that the conclusions are justified for the prevention of ASCVD.


Assuntos
Aterosclerose , Animais , Aterosclerose/sangue , Aterosclerose/epidemiologia , Aterosclerose/prevenção & controle , Consenso , Gorduras na Dieta , Europa (Continente) , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Lipoproteínas LDL/sangue , Ensaios Clínicos Controlados Aleatórios como Assunto , Sociedades Científicas
3.
Pharmacology ; 98(3-4): 134-70, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27251151

RESUMO

BACKGROUND: Positive associations have been observed between cardiovascular disease (CVD) and type 2 diabetes mellitus (DM), but their causal relationship has not been clarified. Nevertheless, guidelines from relevant medical societies recommend using cholesterol lowering medication (statin) for both types of patients. Medicines with several different action mechanisms have been developed, and the effectiveness of different lifestyle modifications has been studied extensively for the prevention of DM, which was successful in improving clinical marker status in relatively short-term treatments, but none have been shown to be effective in improving long-term outcomes (mortality from CVD and all causes). SUMMARY: Statin-induced suppression of prenyl intermediates in the cholesterol biosynthetic pathway has been linked to stimulated atherosclerosis and heart failure. On the other hand, certain types of vegetable oil and hydrogenated oil shortened the survival of stroke-prone spontaneously hypertensive rats by decreasing platelet number, increasing hemorrhagic tendency and damaging kidney functions, which could not be accounted for by their fatty acid and phytosterol compositions. These vegetable oils and medicines such as statin and warfarin share, in part, a common mechanism to inhibit vitamin K2-dependent processes, which was interpreted to lead to increased onset of CVD, DM, chronic kidney disease, bone fracture and even mental disorder. Impaired vitamin K2-dependent processes by some types of vegetable oils and medicines, but not plasma high low density lipoprotein cholesterol, were proposed as the cause of CVD, DM and other lifestyle-related diseases. High n-6/n-3 fatty acid ratio of ingested foods, but not animal fats, was emphasized to be another risk factor for many of the diseases described above. KEY MESSAGES: To date, no randomized controlled trials (RCTs) have been performed to prove the above interpretation. However, the opposite types of RCT trials have been performed by increasing the intake of high-linoleic vegetable oils and reducing that of animal fats, which resulted in increased CVD and all-cause mortality. The amounts of these vegetable oils to exhibit adverse effects in animal studies are not huge (<6 energy %), which should not be overlooked nor disregarded.


Assuntos
Doenças Cardiovasculares/induzido quimicamente , Diabetes Mellitus Tipo 2/induzido quimicamente , Gorduras na Dieta/efeitos adversos , Óleos de Plantas/efeitos adversos , Animais , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/metabolismo , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/metabolismo , Gorduras na Dieta/administração & dosagem , Ingestão de Energia/efeitos dos fármacos , Ingestão de Energia/fisiologia , Humanos , Óleos de Plantas/administração & dosagem , Fatores de Risco
5.
Biol Pharm Bull ; 37(6): 1003-13, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24882411

RESUMO

We investigated whether body temperature (BT) regulatory mechanisms are influenced by dietary fatty acids (FA). Male Wistar rats were fed a high-fat diet containing fish oil (HFD), soybean oil (HSD) or lard (HLD). At the 20-week intervention, the BT of the HSD and HLD groups were lower than that of the normal diet (ND) group in the light and dark periods. The intracerebroventricular injections of interleukin-1ß and bombesin in the HSD group induced greater hyperthermia and weaker hypothermia, respectively, than in the ND group. The HSD differentially affected BT under both physiological and pharmacological conditions. In the hypothalamus, the ratio of n-6/n-3 FAs was higher in the HSD group compared with the ND group. DNA microarrays revealed increased expression of thyroid-stimulating hormone ß-subunit, and decreased expression of several genes in the hypothalamus of the HSD group compared with the ND group. The HSD feeding increased several adipokine concentrations in the plasma. However, there were no adipokines or gene expressions that changed in only the HSD and HLD groups showing significant hypothermia under the physiological condition. These findings suggested that long-term HSD intake produces abnormal BT regulation. It is less likely that adipokines or proteins/peptides are involved in abnormal BT regulation under the physiological conditions after HSD feeding.


Assuntos
Regulação da Temperatura Corporal/efeitos dos fármacos , Dieta Hiperlipídica , Óleo de Soja/farmacologia , Adipocinas/sangue , Animais , Temperatura Corporal/efeitos dos fármacos , Regulação da Temperatura Corporal/genética , Peso Corporal/efeitos dos fármacos , Bombesina/farmacologia , Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/farmacologia , Metabolismo Energético/efeitos dos fármacos , Ácidos Graxos/sangue , Ácidos Graxos/metabolismo , Óleos de Peixe/administração & dosagem , Óleos de Peixe/farmacologia , Expressão Gênica/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Interleucina-1beta/farmacologia , Masculino , Atividade Motora/efeitos dos fármacos , Fotoperíodo , Ratos Wistar , Óleo de Soja/administração & dosagem , Fatores de Tempo
6.
Toxicol Rep ; 9: 256-268, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35242585

RESUMO

This study was conducted to investigate whether or not there are sex differences in canola oil (CAN)-induced adverse events in the rat and to understand the involvement and the role of testosterone in those events, including life-shortening. Stroke-prone spontaneously hypertensive rats (SHRSP) of both sexes were fed a diet containing 10 wt/wt% soybean oil (SOY, control) or CAN as the sole dietary fat. The survival of the males fed the CAN diet was significantly shorter than that of those fed the SOY diet. In contrast, the survival of the females was not affected by CAN. The males fed the CAN diet showed elevated blood pressure, thrombopenia and insulin-tolerance, which are major symptoms of metabolic syndrome, whereas such changes by the CAN diet were not found in the females. Plasma testosterone was significantly lower in animals of both sexes fed the CAN diet than in those fed the SOY diet, but interestingly, the lowered testosterone was accompanied by a marked increase in plasma aldosterone only in the males. These results demonstrate significant sex differences in CAN-toxicity and suggest that those sex differences may be attributable to the increased aldosterone level, which triggers aggravation of the genetic diseases specific to SHRSP, that is, metabolic syndrome-like conditions, but only in the males. The present results also suggest that testosterone may negatively regulate aldosterone production in the physiology of the males, and the inhibition of that negative regulation caused by the CAN diet is one of the possible causes of the adverse events.

8.
Expert Rev Clin Pharmacol ; 13(12): 1289-1294, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33416003

RESUMO

Introduction: The European Society of Cardiology and European Atherosclerosis Society (ESC/EAS) have recently published three major revisions of their guidelines for the management of chronic heart disease, blood lipids, and diabetes. Areas covered: We have scrutinized these guidelines in detail and found that the authors have ignored many studies that are in conflict with their conclusions and recommendations. Expert commentary: The authors of the guidelines have ignored that LDL-cholesterol (LDL-C) of patients with acute myocardial infarction is lower than normal; that high cholesterol is not a risk factor for diabetics; that the degree of coronary artery calcification is not associated with LDL-C; and that 27 follow-up studies have shown that people with high total cholesterol or LDL-C live just as long or longer than people with low cholesterol. They have also ignored the lack of exposure-response in the statin trials; that several of these trials have been unable to lower CVD or total mortality; that no statin trial has succeeded with lowering mortality in women, elderly people, or diabetics; and that cholesterol-lowering with statins has been associated with many serious side effects.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Colesterol/sangue , Guias de Prática Clínica como Assunto/normas , Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/efeitos adversos , Doenças Cardiovasculares/etiologia , LDL-Colesterol/sangue , Europa (Continente) , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Hipercolesterolemia/complicações , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/etiologia , Fatores de Risco
9.
Food Chem Toxicol ; 135: 110927, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31678484

RESUMO

The present study was conducted to examine the influence of dietary canola oil (CAN) and partially-hydrogenated soybean oil (HSO) compared to soybean oil (SOY, control) on the morphology and function of testes using miniature pigs as the test subject. Male miniature pigs were fed a diet containing 10%SOY, 9%CAN+1%SOY, or 9%HSO+1%SOY for 18 months. The scheduled autopsies revealed no abnormalities in histopathological examination of the major organs, except the testes. Atrophy of the seminiferous tubules and hyperplasia in the Leydig cells were found in the SOY and CAN groups. DNA microarray analysis indicated downregulation in the CAN and the HSO groups of genes encoding for gonadotropins in the pituitary gland and of enzymes and proteins involved in steroid hormone metabolism in the testes, compared to the SOY group. Plasma levels of sex hormones in the CAN and HSO groups tended to be higher and testosterone and dihydrotestosteorne in the HSO group were significantly higher than in the SOY group. These results demonstrate that testes are morphologically and functionally affected by the dietary oils, while the plasma steroid hormone levels do not necessarily reflect the gene expression, probably owing to feedback regulation via the gonadal hormones in the hypothalamus-pituitary-gonadal axis.


Assuntos
Óleo de Brassica napus/toxicidade , Óleo de Soja/toxicidade , Testículo/efeitos dos fármacos , Congêneres da Testosterona/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Dieta , Regulação para Baixo/genética , Expressão Gênica/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Suínos , Porco Miniatura , Testículo/metabolismo
10.
Food Chem Toxicol ; 46(7): 2573-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18508177

RESUMO

We intended to determine whether or not dietary canola oil (CO) elevates plasma lipids and oxidative stress, since both of these are, possibly, related to the CO-induced life shortening through exacerbation of hypertension-associated vascular lesions found in stroke-prone spontaneously hypertensive rats (SHRSP). Spontaneously hypertensive rats (SHR) were used in this study to avoid a potential bias in the results due to the irregular death by stroke seen in SHRSP. SHR were fed for 26 weeks on a chow containing either, 10 wt/wt% of CO or soybean oil (SO), i.e., the control. Elevated plasma lipids and glucose-6-phosphate dehydrogenase (G6PD) activation in the liver and erythrocyte were found in SHR fed CO compared to that fed SO, while anti-oxidative enzymes other than G6PD were not activated. The CO diet brought about significant vascular lesions in the kidney, in which abundant cyclooxygenase-2 (COX-2) positive foci were immunochemically located in the juxtaglomerular apparatus. These results suggest that dietary CO induces a hyperlipidemic condition, in which G6PD may serve as an NADPH provider, and aggravates genetic diseases in SHR (also, probably, in SHRSP). The increased COX-2 expression indicates a role of renin-angiotensin-aldosterone system activation in the increased vascular lesions, whereas the effects of oxidative stress remain unclear.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Lipídeos/sangue , Óleos de Plantas/farmacologia , Óleo de Soja/farmacologia , Animais , Glicemia/metabolismo , Encéfalo/patologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Eritrócitos/enzimologia , Ácidos Graxos Monoinsaturados , Hipertensão/sangue , Hipertensão/enzimologia , Hipertensão/genética , Imuno-Histoquímica , Rim/patologia , Fígado/enzimologia , Fígado/patologia , Masculino , Miocárdio/patologia , Óleos de Plantas/administração & dosagem , Óleo de Brassica napus , Ratos , Ratos Endogâmicos SHR , Óleo de Soja/administração & dosagem
12.
Expert Rev Clin Pharmacol ; 11(10): 959-970, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30198808

RESUMO

INTRODUCTION: For half a century, a high level of total cholesterol (TC) or low-density lipoprotein cholesterol (LDL-C) has been considered to be the major cause of atherosclerosis and cardiovascular disease (CVD), and statin treatment has been widely promoted for cardiovascular prevention. However, there is an increasing understanding that the mechanisms are more complicated and that statin treatment, in particular when used as primary prevention, is of doubtful benefit. Areas covered: The authors of three large reviews recently published by statin advocates have attempted to validate the current dogma. This article delineates the serious errors in these three reviews as well as other obvious falsifications of the cholesterol hypothesis. Expert commentary: Our search for falsifications of the cholesterol hypothesis confirms that it is unable to satisfy any of the Bradford Hill criteria for causality and that the conclusions of the authors of the three reviews are based on misleading statistics, exclusion of unsuccessful trials and by ignoring numerous contradictory observations.


Assuntos
Doenças Cardiovasculares/prevenção & controle , LDL-Colesterol/sangue , Hipercolesterolemia/complicações , Aterosclerose/etiologia , Aterosclerose/prevenção & controle , Doenças Cardiovasculares/etiologia , Colesterol/sangue , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Prevenção Primária/métodos , Fatores de Risco
14.
Lipids ; 42(9): 821-5, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17546469

RESUMO

Healthy ageing is gaining attention in the lipid nutrition field. As in vivo biomarkers of healthy ageing, we have evaluated the survival, learning/memory performance, and physical potencies in rodents fed a diet supplemented with high-linoleic acid (LNA, omega6) safflower oil or high-alpha-linolenic acid (ALA, omega3) perilla oil for long periods. The results suggested that perilla oil with a low omega6/omega3 ratio is beneficial for healthy ageing. In order to address this issue further, we determined the survival of stroke-prone SHR (SHRSP) rats fed a conventional rodent diet supplemented with 10% fat or oil. Survival was longer with omega3-rich oils compared with omega6-rich oils. However, some kinds of vegetable oils and hydrogenated oils shortened the survival of SHRSP rats to an unusual degree (ca. 40% compared with that of omega6-rich oil) that could not be accounted for by the fatty acid and phytosterol composition of the oils. The observed decrease in platelet counts was associated with pathological changes in the kidney and other organs. Dihydro-vitamin K1 is proposed as a likely candidate as a stroke-stimulating factor in hydrogenated oils. Thus, factors other than fatty acids (omega6/omega3 balance) and phytosterols must be taken into account when fats and oils are evaluated in relation to healthy ageing.


Assuntos
Envelhecimento/efeitos dos fármacos , Gorduras Insaturadas na Dieta/farmacologia , Animais , Humanos , Óleos de Plantas/farmacologia , Ratos , Ratos Endogâmicos SHR , Óleo de Cártamo/farmacologia , Acidente Vascular Cerebral/enzimologia , Acidente Vascular Cerebral/metabolismo , Ácido alfa-Linolênico/farmacologia
15.
Food Chem Toxicol ; 44(7): 952-63, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16364530

RESUMO

To identify the causative substances for the shortening of survival time by rapeseed (Canola) oil in stroke-prone spontaneously hypertensive rats (SHRSP), SHRSP were fed on a standard chow supplemented with 10 w/w% soybean oil (control), rapeseed oil, one of the fractions of rapeseed oil obtained by super critical gas extraction (SCE) under a pressure of 180-bar or 350-bar, at 40 degrees C, or the residue from the extraction (with 0.5% NaCl in drinking water). In another series of experiment, SHRSP were fed for 8 weeks on the above-mentioned diets without salt loading and autopsied. Fatty acid compositions in these diets were similar, except in the soybean oil diet, and phytosterol contents were: (diet containing) 180-bar fraction>residue>rapeseed oil>350-bar fraction>soybean oil. Survival times in the rapeseed oil, 350-bar fraction and residue groups were shorter than, whereas that in the 180-bar fraction was similar to in the soybean oil group. In the 8-week feeding experiment, chronic nephropathy was found frequently in the groups other than the soybean oil group. The heart weights were higher in the rapeseed oil and residue groups. Cerebral necrosis was found in the residue group. Taken together, the followings are concluded, (1) Neither the fatty acid composition, nor the amount of phytosterols in the diets appeared to be decisive in the shortening of life. (2) SCE appeared to produce a safe (180-bar) fraction, though it failed to separate clearly the causative substances into specific fractions. (3) The factors that facilitate the genetic disease of SHRSP appear to exist in rapeseed oil. However, they might not be identical to those responsible for the life-shortening, since there were no findings common across the rapeseed oil, 350-bar and residue groups, which showed similar life-shortening.


Assuntos
Óleos de Plantas/química , Óleos de Plantas/toxicidade , Algoritmos , Animais , Peso Corporal/efeitos dos fármacos , Dieta , Ingestão de Líquidos , Ingestão de Alimentos , Ácidos Graxos/análise , Ácidos Graxos Monoinsaturados , Testes de Função Renal , Masculino , Tamanho do Órgão/efeitos dos fármacos , Fitosteróis/análise , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Óleo de Brassica napus , Ratos , Ratos Endogâmicos SHR , Óleo de Soja/química , Óleo de Soja/toxicidade , Análise de Sobrevida , Fatores de Tempo
16.
BMJ Open ; 6(6): e010401, 2016 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-27292972

RESUMO

OBJECTIVE: It is well known that total cholesterol becomes less of a risk factor or not at all for all-cause and cardiovascular (CV) mortality with increasing age, but as little is known as to whether low-density lipoprotein cholesterol (LDL-C), one component of total cholesterol, is associated with mortality in the elderly, we decided to investigate this issue. SETTING, PARTICIPANTS AND OUTCOME MEASURES: We sought PubMed for cohort studies, where LDL-C had been investigated as a risk factor for all-cause and/or CV mortality in individuals ≥60 years from the general population. RESULTS: We identified 19 cohort studies including 30 cohorts with a total of 68 094 elderly people, where all-cause mortality was recorded in 28 cohorts and CV mortality in 9 cohorts. Inverse association between all-cause mortality and LDL-C was seen in 16 cohorts (in 14 with statistical significance) representing 92% of the number of participants, where this association was recorded. In the rest, no association was found. In two cohorts, CV mortality was highest in the lowest LDL-C quartile and with statistical significance; in seven cohorts, no association was found. CONCLUSIONS: High LDL-C is inversely associated with mortality in most people over 60 years. This finding is inconsistent with the cholesterol hypothesis (ie, that cholesterol, particularly LDL-C, is inherently atherogenic). Since elderly people with high LDL-C live as long or longer than those with low LDL-C, our analysis provides reason to question the validity of the cholesterol hypothesis. Moreover, our study provides the rationale for a re-evaluation of guidelines recommending pharmacological reduction of LDL-C in the elderly as a component of cardiovascular disease prevention strategies.


Assuntos
Doenças Cardiovasculares/mortalidade , LDL-Colesterol/sangue , Mortalidade , Idoso , Humanos , Pessoa de Meia-Idade , Fatores de Risco
17.
Biochim Biophys Acta ; 1631(1): 17-25, 2003 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-12573445

RESUMO

We have shown previously that the phospholipase A (PLA) activity specific for phosphatidic acid (PA) in porcine platelet membranes is of the A(1) type (PA-PLA(1)) [J. Biol. Chem. 259 (1984) 5083]. In the present study, the PA-PLA(1) was solubilized in Triton X-100 from membranes pre-treated with 1 M NaCl, and purified 280-fold from platelet homogenates by sequential chromatography on blue-Toyopearl, red-Toyopearl, DEAE-Toyopearl, green-agarose, brown-agarose, polylysine-agarose, palmitoyl-CoA-agarose and blue-5PW columns. In the presence of 0.1% Triton X-100 in the assay mixture, the partially purified enzyme hydrolyzed the acyl group from the sn-1 position of PA independently of Ca(2+) and was highly specific for PA; phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine (PS), and phosphatidylinositol (PI) were poor substrates. The enzyme exhibited lysophospholipase activity for l-acyl-lysoPA at 7% of the activity for PA hydrolysis but no lipase activity was observed for triacylglycerol (TG) and diacylglycerol (DG). At 0.025% Triton X-100, the enzyme exhibited the highest activity, and PA was the best substrate, but PE was also hydrolyzed substantially. The partially purified PA-PLA(1) in porcine platelet membranes was shown to be different from previously purified and cloned phospholipases and lipases by comparing the sensitivities to a reducing agent, a serine-esterase inhibitor, a PLA(2) inhibitor, a Ca(2+)-independent phospholipase A(2) inhibitor, and a DG lipase inhibitor.


Assuntos
Plaquetas/química , Ácidos Fosfatídicos , Fosfolipases A/isolamento & purificação , Animais , Membrana Celular/química , Cromatografia/métodos , Eletroforese em Gel de Poliacrilamida , Lisofosfolipídeos/biossíntese , Octoxinol , Fosfolipases A/química , Fosfolipases A/metabolismo , Especificidade por Substrato , Suínos
18.
Yakugaku Zasshi ; 125(11): 833-52, 2005 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-16272805

RESUMO

The cholesterol hypothesis implies that reducing the intake of saturated fatty acids and cholesterol and increasing that of polyunsaturated fatty acid are effective in lowering serum total cholesterol (TC), and thereby reducing the incidence of coronary heart disease (CHD). However, these dietary recommendations are essentially ineffective in reducing TC in the long run, but rather increase mortality rates from CHD and all causes. The reported "apparent relative risk of high TC in CHD mortality" (the ratio of mortality at the highest/lowest TC levels) varied several-fold among populations studied. The incidence of familial hypercholesterolemia (FH) in a population was proposed to be a critical factor in the observed variability, which could be accounted for by assuming that 1) the high CHD mortality rate in high-TC groups is mainly a reflection of the incidence and severity of FH, and 2) high TC is not a causative factor of CHD in non-FH cases. This interpretation is supported by recent observations that high TC is not positively associated with high CHD mortality rates among general populations more than 40-50 years of age. More importantly, higher TC values are associated with lower cancer and all-cause mortality rates among these populations, in which relative proportions of FH are likely to be low (circa 0.2%). Although the effectiveness of statins in preventing CHD has been accepted in Western countries, little benefit seems to result from efforts to limit dietary cholesterol intake or to TC values to less than approximately 260 mg/dl among the general population and the elderly. Instead, an unbalanced intake of omega6 over omega3 polyunsaturated fats favors the production of eicosanoids, the actions of which lead to the production of inflammatory and thrombotic lipid mediators and altered cellular signaling and gene expression, which are major risk factors for CHD, cancers, and shorter longevity. Based on the data reviewed here, it is urgent to change the direction of current cholesterol-related medication for the prevention of CHD, cancer, and all-cause mortality.


Assuntos
Anticolesterolemiantes , Aterosclerose/etiologia , Aterosclerose/prevenção & controle , Doença das Coronárias/etiologia , Doença das Coronárias/prevenção & controle , Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácido Eicosapentaenoico/administração & dosagem , Ácido alfa-Linolênico/administração & dosagem , Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/efeitos adversos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Hiperlipoproteinemia Tipo II/mortalidade , Inflamação/etiologia , Inflamação/prevenção & controle , Mediadores da Inflamação/metabolismo , Ácido Linoleico/administração & dosagem , Ácido Linoleico/efeitos adversos , Neoplasias/etiologia , Neoplasias/prevenção & controle , Fatores de Risco , Trombose/etiologia , Trombose/prevenção & controle
19.
Expert Rev Clin Pharmacol ; 8(2): 189-99, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25655639

RESUMO

In contrast to the current belief that cholesterol reduction with statins decreases atherosclerosis, we present a perspective that statins may be causative in coronary artery calcification and can function as mitochondrial toxins that impair muscle function in the heart and blood vessels through the depletion of coenzyme Q10 and 'heme A', and thereby ATP generation. Statins inhibit the synthesis of vitamin K2, the cofactor for matrix Gla-protein activation, which in turn protects arteries from calcification. Statins inhibit the biosynthesis of selenium containing proteins, one of which is glutathione peroxidase serving to suppress peroxidative stress. An impairment of selenoprotein biosynthesis may be a factor in congestive heart failure, reminiscent of the dilated cardiomyopathies seen with selenium deficiency. Thus, the epidemic of heart failure and atherosclerosis that plagues the modern world may paradoxically be aggravated by the pervasive use of statin drugs. We propose that current statin treatment guidelines be critically reevaluated.


Assuntos
Aterosclerose/etiologia , Insuficiência Cardíaca/etiologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Animais , Aterosclerose/epidemiologia , Aterosclerose/patologia , Colesterol/sangue , Glutationa Peroxidase/metabolismo , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Mitocôndrias/patologia , Guias de Prática Clínica como Assunto , Selênio/deficiência , Selênio/metabolismo
20.
Artigo em Inglês | MEDLINE | ID: mdl-25451556

RESUMO

To address preventive effects of n-3 PUFAs/LC n-3 PUFAs on CRTs, a randomized controlled trial was conducted. One-hundred four experimental group participants were advised to increase intake of n-3 PUFAs, including fish/shell fish, fish oil supplements and perilla oils, and to decrease consumption of n-6 PUFAs and fats/oils as a whole for 24 months. One-hundred one control group participants were only cautioned to reduce consumption of fats/oils as a whole. Random allocation was satisfactorily attained, and participants sufficiently complied with our regimen. Intakes, plasma concentrations, and compositions of the RBC and sigmoid colon membranes of n-3 PUFAs, LC n-3 PUFAs, EPA and DHA increased, and the ratios of n-6 PUFAs/n-3 PUFAs and AA/LC n-3 PUFAs decreased without any adverse response. Twenty-four months after the intervention, the multivariate-adjusted hazard ratio (95% confidence intervals) was estimated to be 0.805 (0.536-1.209) with a signal towards the reduced CRT incidence.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/prevenção & controle , Gorduras Insaturadas na Dieta/administração & dosagem , Ácidos Graxos Ômega-3/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Neoplasias Colorretais/sangue , Neoplasias Colorretais/cirurgia , Gorduras Insaturadas na Dieta/sangue , Seguimentos , Humanos , Adesão à Medicação , Resultado do Tratamento
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