Dietary fats and other nutrients on stroke

Sodium Intake and Target Organ Damage in Hypertension-An Update about the Role of a Real Villain

Salt intake is too high for safety nowadays. The main active ion in salt is sodium. The vast majority of scientific evidence points out the importance of sodium restriction for decreasing cardiovascular risk. International Guidelines recommend a large reduction in sodium consumption to help reduce blood pressure, organ damage, and cardiovascular risk. Regulatory authorities across the globe suggest a general restriction of sodium intake to prevent cardiovascular diseases. In spite of this seemingly unanimous consensus, some researchers claim to have evidence of the unhealthy effects of a reduction of sodium intake, and have data to support their claims. Evidence is against dissenting scientists, because prospective, observational, and basic research studies indicate that sodium is the real villain: actual sodium consumption around the globe is far higher than the safe range. Sodium intake is directly related to increased blood pressure, and independently to the enlargement of cardiac mass, with a possible independent role in inducing left ventricular hypertrophy. This may represent the basis of myocardial ischemia, congestive heart failure, and cardiac mortality. Although debated, a high sodium intake may induce initial renal damage and progression in both hypertensive and normotensive subjects. Conversely, there is general agreement about the adverse role of sodium in cerebrovascular disease. These factors point to the possible main role of sodium intake in target organ damage and cardiovascular events including mortality. This review will endeavor to outline the existing evidence.

Age-Period-Cohort Analysis of Stroke Mortality Attributable to High Sodium Intake in China and Japan

Background and Purpose- The aim of this study is to assess the long-term trends in stroke mortality attributable to high sodium intake in China and Japan during the period 1990 to 2016. Methods- The mortality data were obtained from the GBD study (Global Burden of Disease) 2016 and were analyzed using an age-period-cohort method. Results- The age-standardized mortality rates showed declining trends for high sodium intake-related stroke mortality. The overall net drifts per year were -3.1% for Chinese men and -5.0% for Chinese women; and -4.6% for Japanese men and -5.7% for Japanese women. The local drift values were below zero in all age groups for both sexes in both countries, and all local drift values of female participants were below their counterparts of male participants. The longitudinal age curves of high sodium intake-attributable stroke mortality increased rapidly for both sexes in China, whereas those of Japanese were slowly rising. The period and cohort rate ratios were found to have similar downward patterns for both sexes in both countries, with a quicker decline for women than for men (significantly with P<0.05 for all). Conclusions- The age-standardized mortality rates, the period effect and the cohort effect of stroke mortality attributable to high sodium intake in China and Japan have been declining in both sexes and all age groups from 1990 to 2016. Consequently, sodium-reduction strategies are of low cost and effective for the prevention of stroke. It is necessary to educate the nation with the correct knowledge on healthy diet and techniques to reduce salt consumption.

Eating habits in the population of the Aeolian Islands: an observational study

OBJECTIVE

We conducted a study to describe food profile, health status and stroke risk factors in the population of the Aeolian Islands.

DESIGN

Self-administrated questionnaires regarding eating habits, health status and stroke risk factors were obtained from a sample of the general Aeolian population. We analysed the difference from common healthy eating habits indicated by the Italian Institute of Nutrition.

SETTING

Current evidence finds the Mediterranean diet is a protective factor for cardio- and cerebrovascular diseases. The Aeolian Islands are an interesting study setting because of their peculiarity in the epidemiology of cerebrovascular and neurodegenerative diseases.

PARTICIPANTS

Individuals (n 586; age range 15-93 years; mean 52 (sd 18) years) living in the Aeolian Islands.

RESULTS

We found low fish consumption in 13·3% and vitamin intake deficiency in 5·8% of participants. A marked excess of saturated fats was observed in 71·0% of participants. Sodium excess was reported almost in half of participants (49·0%). Eating habits were characterized by high consumption of fruits and vegetables, consistent use of olive oil and scanty use of cured meat. Health status as evaluated by the General Health Questionnaire was characterized by 'normal distress' level in the majority of participants.

CONCLUSIONS

Study findings show the eating habits and health status of the Aeolian people in an interesting setting of low incidence of cerebrovascular disease. This nutrition regimen has been proved to be protective against cerebrovascular disease. Nutrition is likely to contribute to the low incidence of stroke in this population.

Therapeutic effects of dietary intervention on neuroinflammation and brain metabolism in a rat model of photothrombotic stroke

INTRODUCTION

A possible target for stroke management is modulation of neuroinflammation. Evidence suggests that food components may exert anti-inflammatory properties and thus may reduce stroke-induced brain damage.

AIM

To investigate the efficacy of a diet, containing anti-inflammatory ingredients, as treatment for focal ischemic brain damage induced by photothrombotic stroke in the somatosensory cortex of rats.

RESULTS

Brain lesions were surrounded by strong astrogliosis on both day 7 and day 21 after stroke and were accompanied by a trend toward globally decreased glucose metabolism on day 7. The investigational diet applied 2 weeks before the ischemia did not affect astrocyte activation on day 7, but reduced it at day 21. The investigational diet applied immediately after the ischemia, increased astrocyte activation on day 7 and completely reversed this effect on day 21. Moreover, postischemic intervention increased glucose metabolism in somatosensory cortex ipsilateral to the lesion on day 7.

CONCLUSION

This study reveals potentially beneficial effects of a diet containing elevated amounts of anti-inflammatory nutrients on the recovery from ischemic brain damage. Therefore, dietary intervention can be considered as an adjuvant therapy for recovery from this brain pathology.

Associations of serum n-3 and n-6 PUFA and hair mercury with the risk of incident stroke in men: the Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD)

PUFA have been associated with lower risk of CVD, but less is known about their association with stroke risk. Fish, a major source of n-3 PUFA, may also contain methylmercury, which has been associated with higher risk of CVD and attenuation of the benefits of long-chain n-3 PUFA. We investigated the associations of serum n-3 and n-6 PUFA and hair Hg with risk of stroke in men. A total of 1828 men from the prospective, population-based Kuopio Ischaemic Heart Disease Risk Factor Study, aged 42-60 years and free of CVD at baseline in 1984-1989 were studied. Cox regression models were used for the analyses. During the mean follow-up of 21·2 years, 202 stroke cases occurred, of which 153 were ischaemic strokes. After adjustment for age and examination year, the only statistically significant association among the n-3 and n-6 PUFA was observed between the n-3 PUFA α-linolenic acid and risk of haemorrhagic stroke (hazard ratio in the highest v. the lowest quartile 0·33; 95 % CI 0·13, 0·86; P trend=0·03). However, further adjustments attenuated the association to statistically non-significant. Hair Hg was not associated with stroke risk, but among those with hair Hg above the median level, higher serum long-chain n-3 PUFA concentrations were associated with a higher risk of ischaemic stroke. In our cohort of men, serum n-3 or n-6 PUFA or hair Hg were not associated with stroke risk; however, the interaction between Hg and long-chain n-3 PUFA with regard to ischaemic stroke risk warrants further investigation.

The effects of black garlic (Allium satvium) extracts on lipid metabolism in rats fed a high fat diet

BACKGROUD/OBEJECTIVES

The mechanism of how black garlic effects lipid metabolism remains unsolved. Therefore, the objectives of this study were to determine the effects of black garlic on lipid profiles and the expression of related genes in rats fed a high fat diet.

MATERIALS/METHODS

Thirty-two male Sqrague-Dawley rats aged 4 weeks were randomly divided into four groups (n=8) and fed the following diets for 5 weeks: normal food diet, (NF); a high-fat diet (HF); and a high-fat diet + 0.5% or 1.5% black garlic extract (HFBG0.5 or HFBG1.5). Body weights and blood biochemical parameters, including lipid profiles, and expressions of genes related to lipid metabolism were determined.

RESULTS

Significant differences were observed in the final weights between the HFBG1.5 and HF groups. All blood biochemical parameters measured in the HFBG1.5 group showed significantly lower values than those in the HF group. Significant improvements of the plasama lipid profiles as well as fecal excretions of total lipids and triglyceride (TG) were also observed in the HFBG1.5 group, when compared to the HF diet group. There were significant differences in the levels of mRNA of sterol regulatory element binding protein-1c (SREBP-1c), acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), and glucose-6-phosphate dehydrogenase (G6PDH) in the HFBG1.5 group compared to the HF group. In addition, the hepatic expression of (HMG-CoA) reductase and Acyl-CoA cholesterol acyltransferase (ACAT) mRNA was also significantly lower than the HF group.

CONCLUSIONS

Consumption of black garlic extract lowers SREBP-1C mRNA expression, which causes downregulation of lipid and cholestrol metahbolism. As a result, the blood levels of total lipids, TG, and cholesterol were decreased.

Intake of trans fat and incidence of stroke in the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort

BACKGROUND

Whether elevated intakes of trans fatty acids (TFAs) increase the risk of stroke remains unclear. Except for the Women's Health Initiative-Observational Study, most studies that directly assessed the association between TFA intake and stroke yielded null results.

OBJECTIVE

The aim of this study was to investigate the association between TFA intake and stroke incidence.

DESIGN

We prospectively investigated the association between TFA intake and stroke incidence in black and white men and women (n = 17,107) from the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort. Participants were recruited between 2003 and 2007 from the continental United States and followed for incident stroke. Diet was assessed by using the Block 1998 food-frequency questionnaire. Cox regression was used to test whether energy-adjusted TFA intake in 1-SD increments was associated with incident stroke.

RESULTS

During a median follow-up of 7 y, 479 strokes were identified, including 401 ischemic strokes. Sex modified the association between TFA intake and stroke (P-interaction = 0.06), and thus the results were stratified by sex. In fully adjusted models, a 1-SD (2-g/d) increase in TFA intake was associated with an increased risk of any stroke in men (HR: 1.14; 95% CI: 1.02, 1.28) but not in women (HR: 0.93; 95% CI: 0.79, 1.11). Similarly, our results showed an increased risk of ischemic stroke in men (HR: 1.13; 95% CI: 1.00, 1.28) but not in women (HR: 0.93; 95% CI: 0.77, 1.12).

CONCLUSIONS

We show that sex modifies the association between TFA intake and stroke; for every 2-g/d increase in TFA intake, there was a 14% increase in the risk of stroke in men but not in women. Our findings provide further evidence to support the concerted effort to minimize TFAs in the diet.