Association between Protein Intake and the Risk of Hypertension among Chinese Men and Women: A Longitudinal Study

Novel Metabolites Associated With Blood Pressure After Dietary Interventions

BACKGROUND

The blood pressure (BP) etiologic study is complex due to multifactorial influences, including genetic, environmental, lifestyle, and their intricate interplays. We used a metabolomics approach to capture internal pathways and external exposures and to study BP regulation mechanisms after well-controlled dietary interventions.

METHODS

In the ProBP trail (Protein and Blood Pressure), a double-blinded crossover randomized controlled trial, participants underwent dietary interventions of carbohydrate, soy protein, and milk protein, receiving 40 g daily for 8 weeks, with 3-week washout periods. We measured plasma samples collected at baseline and at the end of each dietary intervention. Multivariate linear models were used to evaluate the association between metabolites and systolic/diastolic BP. Nominally significant metabolites were examined for enriching biological pathways. Significant ProBP findings were evaluated for replication among 1311 participants of the BHS (Bogalusa Heart Study), a population-based study conducted in the same area as ProBP.

RESULTS

After Bonferroni correction for 77 independent metabolite clusters (α=6.49×10-4), 18 metabolites were significantly associated with BP at baseline or the end of a dietary intervention, of which 11 were replicated in BHS. Seven emerged as novel discoveries, which are as follows: 1-linoleoyl-GPE (18:2), 1-oleoyl-GPE (18:1), 1-stearoyl-2-linoleoyl-GPC (18:0/18:2), 1-palmitoyl-2-oleoyl-GPE (16:0/18:1), maltose, N-stearoyl-sphinganine (d18:0/18:0), and N6-carbamoylthreonyladenosine. Pathway enrichment analyses suggested dietary protein intervention might reduce BP through pathways related to G protein-coupled receptors, incretin function, selenium micronutrient network, and mitochondrial biogenesis.

CONCLUSIONS

Seven novel metabolites were identified to be associated with BP at the end of different dietary interventions. The beneficial effects of protein interventions might be mediated through specific metabolic pathways.

Association between PEMT rs7946 and blood pressure levels in Chinese adolescents

OBJECTIVES

This study was to explore blood pressure levels in Chinese adolescents with different genotypes of phosphatidylethanolamine N-methyltransferase (PEMT) gene ( PEMT ) rs7946, as well as effects of dietary intake on blood pressure levels with different genders and different genotypes of PEMT rs7946.

METHODS

PEMT rs7946 genotypes were identified by PCR-restriction fragment length polymorphism and verified by DNA sequencing. Blood pressure was measured using a standard mercury sphygmomanometer. Dietary intakes were analyzed based on a 3-day diet diary, and dietary components were calculated using computer software.

RESULTS

A total of 721 high school students (314 males and 407 females) at the age of 16.86 ± 0.59 years were included. The A allele carriers of PEMT rs7946 had increased levels of SBP, DBP, mean arterial pressure (MAP) and pulse pressure (PP) than the GG homozygotes in the female subjects. There were significant interactions between PEMT rs7946 and gender on SBP and MAP levels, regardless of whether an unadjusted or adjusted model was used. When dietary intake was taken into account, fat intake was positively associated with SBP and PP in the male GG homozygotes, while protein intake was positively associated with PP in the female A allele carriers of PEMT rs7946.

CONCLUSION

This study suggests that PEMT rs7946 is significantly associated with blood pressure levels in human being. There might be interactions among PEMT rs7946, gender, and dietary intake on blood pressure levels in the adolescent population.

Effect of Relative Protein Intake on Hypertension and Mediating Role of Physical Fitness and Circulating Fatty Acids: A Mendelian Randomization Study

OBJECTIVE

To investigate the causal effect of protein intake on hypertension and the related mediating pathways.

PATIENTS AND METHODS

Using genome-wide association study summary statistics of European ancestry, we applied univariable and multivariable Mendelian randomization to estimate the bidirectional associations of relative protein intake and related metabolomic signatures with hypertension (FinnGen: Ncase=42,857/Ncontrol=162,837; UK Biobank: Ncase=77,723/Ncontrol=330,366) and blood pressure (International Consortium of Blood Pressure: N=757,601) and two-step Mendelian randomization to assess the mediating roles of 40 cardiometabolic factors therein. Mendelian randomization estimates of hypertension from FinnGen and UK Biobank were meta-analyzed without heterogeneity. We performed the study from May 15, 2023, to September 15, 2023.

RESULTS

Each 1-SD higher relative protein intake was causally associated with 69% (odds ratio, 0.31; 95% CI, 0.11 to 0.89) lower hypertension risk independent of the effects of other macronutrients, and was the only macronutrient associated with 2.21 (95% CI, 0.52 to 3.91) mm Hg lower pulse pressure, in a unidirectional manner. Higher plant protein-related metabolomic signature (glycine) was associated with lower hypertension risk and pulse pressure, whereas higher animal protein-related metabolomic signatures (leucine, isoleucine, valine, and isovalerylcarnitine [only systolic blood pressure]) were associated with higher hypertension risk, pulse pressure, and systolic blood pressure. The effect of relative protein intake on hypertension was causally mediated by frailty index (mediation proportion, 40.28%), monounsaturated fatty acids (13.81%), saturated fatty acids (11.39%), grip strength (5.34%), standing height (3.99%), and sitting height (3.61%).

CONCLUSION

Higher relative protein intake causally reduces the risk of hypertension, partly mediated by physical fitness and circulating fatty acids.

Gut Microbiome Interactions with Oxidative Stress: Mechanisms and Consequences for Health

Understanding how gut flora interacts with oxidative stress has been the subject of significant research in recent years. There is much evidence demonstrating the existence of the microbiome-oxidative stress interaction. However, the biochemical basis of this interaction is still unclear. In this narrative review, possible pathways of the gut microbiota and oxidative stress interaction are presented, among which genetic underpinnings play an important role. Trimethylamine-N-oxide, mitochondria, short-chain fatty acids, and melatonin also appear to play roles. Moreover, the relationship between oxidative stress and the gut microbiome in obesity, metabolic syndrome, chronic ethanol consumption, dietary supplements, and medications is considered. An investigation of the correlation between bacterial community features and OS parameter changes under normal and pathological conditions might provide information for the determination of new research methods. Furthermore, such research could contribute to establishing a foundation for determining the linkers in the microbiome-OS association.

Untangling pathways of risk factors associated with hypertension among dysglycemia adults in eastern China: a structural equation model approach

BACKGROUND AND AIMS

Using structural equation model (SEM) to test a conceptual model of pathways of developing hypertension among dysglycemia (IFG and T2DM) adults in Eastern China, emphasizing the unique mediation effect of insulin resistance and obesity on the relationship between modified/unmodified factors and hypertension.

METHODS AND RESULTS

Participants with dysglycemia (n = 10,401) were extracted from the survey of Chronic Disease and Risk Factor Surveillance in Nanjing, the capital of Jiangsu Province in China. Dietary patterns were identified by using principal component analysis (PCA). SEM was employed to evaluate multiple pathways of hypertension among participants with IFG and T2DM. Three dietary patterns were derived using PCA. The tuber animal food pattern (OR = 0.825, 95% CI 0.723-0.940) and the balanced food pattern (OR = 0.812, 95% CI 0.715-0.922) were negatively associated with hypertension, while the Chinese rural food pattern (OR = 1.163, 95% CI 1.019-1.328) was positively associated with hypertension. The best SEM model showed that BMI (0.140), smoking (0.048) and Chinese rural food pattern (0.022) positively associated with hypertension; while tuber animal food pattern (- 0.025) had a negative direct effect on hypertension. Notably, insulin resistance could mediate the link between lifestyles (smoking and dietary patterns) and hypertension.

CONCLUSION

Accordingly, we emphasized the importance of lifestyle intervention, mainly including obesity management, choosing healthy diets and decreasing smoking control, which may profoundly benefit this high-risk group among Chinese population.

Nutrient patterns in relation to metabolic health status and serum levels of brain-derived neurotrophic factor (BDNF) and adropin in adults

The present study aimed to investigate the association of nutrient patterns (NPs) with metabolic health status and serum levels of brain-derived neurotrophic factor (BDNF) and adropin in Iranian adults. This cross-sectional survey was performed on 527 adults aged 20-60 years in Isfahan, Iran. To evaluate dietary intake, a validated 168-item semi-quantitative food frequency questionnaire (FFQ) was used. Participants were categorized as metabolically healthy (MH) and metabolically unhealthy (MU) according to their glycemic and lipid profile, insulin resistance (IR), and inflammation status. An overnight fasting blood sample was collected from each participant and serum levels of BDNF and adropin were assessed. A total of 42.50% of participants were recognized as MU. Three NPs were recognized by factor analysis that labeled as "high animal protein" (NP1), "high vegetable" (NP2), and "high carbohydrate" (NP3) patterns. Moderate adherence to NP2 was related to a lower risk of MU (ORT2 vs. T1 = 0.38, 95% CI: 0.18-0.76). Moreover, high adherence of NP2 (T3 vs. T1) was inversely associated with hypertriglyceridemia (OR = 0.27, 95% CI: 0.11-0.65; P-trend < 0.001) and high hs-CRP values (OR = 0.29, 95% CI: 0.09-1.00; P-trend = 0.03). No significant association was observed between adherence of NP1 and NP3 with MU in crude and adjusted models. However, negative associations were found between moderate adherence to NP3 and insulin resistance (IR) (OR = 0.23, 95% CI: 0.06-0.91) as well as high adherence to NP1 and hypertension (OR = 0.23, 95% CI: 0.09-0.61; P-trend < 0.001). NPs were not associated with serum BDNF and adropin values.

Adherence to aerobic training combined with high protein intake is associated with low blood pressure in Italian older adults: a cross-sectional study

BACKGROUND

Lifestyle habits have a key role in cardiometabolic health. The effects of combined aerobic training (AT) and high protein intake (HPI) on cardiometabolic parameters in older adults are not well established.

AIMS

To investigate the association of AT and HPI with blood pressure (BP), blood glucose, and total blood cholesterol levels in a sample of Italian older adults enrolled in the Longevity Check-up 7 + (Lookup 7 +) study.

METHODS

Lookup 7 + is an ongoing project started in June 2015 and conducted in unconventional settings (e.g., exhibitions, malls, health promotion campaigns) across Italy with the aim of fostering adoption of healthy lifestyles in the general population. For the present investigation, analyses were conducted in participants 65 + years and with body mass index values ≥ 18.5 kg/m2 (n = 3219). Systolic (SBP) and diastolic BP (DBP), blood glucose, and total blood cholesterol were measured. Protein intake was estimated using a 12-item food frequency questionnaire. HPI was operationalized as a daily protein intake ≥ 0.8 g/kg of body weight. AT was operationalized as the practice of running and/or swimming for 60 + minutes at least twice weekly during the previous year.

RESULTS

The mean age of the 3219 participants was 72.7 ± 5.7 years, and 55.2% were women. Adherence to AT combined with a HPI was negatively and independently associated with SPB (β: - 4.976; 95% confidence interval: - 9.8 to - 0.08). No other significant associations were observed.

DISCUSSION AND CONCLUSIONS

Our results indicate that AT combined with HPI was negatively associated with SBP in a large and relatively unselected sample of Italian older adults living in the community. These findings need confirmation by ad hoc designed studies.

The Effects of Dietary Protein and Polysaccharide Fortification on Disease

Proteins and polysaccharides are versatile natural macromolecules that are ubiquitous in nature, and a tailored diet that is fortified with them has been developed to ameliorate a wide array of diseases [...].

Hypertension in China: epidemiology and treatment initiatives

The past two to three decades have seen a steady increase in the prevalence of hypertension in China, largely owing to increased life expectancy and lifestyle changes (particularly among individuals aged 35-44 years). Data from the China hypertension survey conducted in 2012-2015 revealed a high prevalence of grade 3 hypertension (systolic blood pressure ≥180 mmHg and diastolic blood pressure ≥110 mmHg) in the general population, which increased with age to up to 5% among individuals aged ≥65 years. The risk profile of patients with hypertension in China has also been a subject of intense study in the past 30 years. Dietary sodium and potassium intake have remained largely the same in China in the past three decades, and salt substitution strategies seem to be effective in reducing blood pressure levels and the risk of cardiovascular events and death. However, the number of individuals with risk factors for hypertension and cardiovascular disease in general, such as physical inactivity and obesity, has increased dramatically in the same period. Moreover, even in patients diagnosed with hypertension, their disease is often poorly managed owing to a lack of patient education and poor treatment compliance. In this Review, we summarize the latest epidemiological data on hypertension in China, discuss the risk factors for hypertension that are specific to this population, and describe several ongoing nationwide hypertension control initiatives that target these risk factors, especially in the low-resource rural setting.

Protein Intake Is Associated with Blood Pressure and Cholesterol Levels in Italian Older Adults: A Cross-Sectional Study

The present study was conducted to test the association between protein intake and blood pressure, glucose levels, and blood cholesterol in a large sample of Italian older adults. Longevity Check-up 7+ (Lookup 7+) is an ongoing project that started in June 2015. The project is conducted in unconventional settings (e.g., exhibitions, malls, health promotion campaigns) across Italy with the aim of fostering adoption of healthy lifestyles in the general population. For the present study, participants were eligible if they were 65+ years and provided written informed consent. Systolic (SBP) and diastolic blood pressure (DBP), and blood glucose and cholesterol levels were assessed. Protein intake was estimated using a 12-item food frequency questionnaire. Three-thousand four-hundred and four older adults were included in the study. The results of the linear regression showed an inverse association between protein intake (as a continuous variable) and DBP, and a positive correlation with blood cholesterol levels. The findings of the present study indicate that a high intake of protein was negatively associated with DBP and positively associated with total blood cholesterol levels in a large cohort of Italian older adults, after adjustment for numerous covariates.

High Protein Intake at Lunch Is Negatively Associated with Blood Pressure in Community-Dwelling Older Adults: A Cross-Sectional Study

BACKGROUND

The present study was conducted to explore the association between protein intake across the main meals and hypertension (HTN)-related parameters in community-dwelling Brazilian older adults.

METHODS

Brazilian community-dwelling older adults were recruited in a senior center. Dietary habits were assessed through 24 h recall. Protein intake was classified as high and low according to median and recommended dietary allowance values. Absolute and body weight (BW)-adjusted protein consumption levels were quantified and analyzed according to ingestion across the main meals. Systolic (SBP) and diastolic blood pressure (DBP) were measured using an oscilometric monitor. Participants were categorized as hypertensive according to physician diagnosis or the detection of high SBP and/or DBP values.

RESULTS

One hundred ninety-seven older adults were enrolled in the present study. Protein intake at lunch was independently and negatively associated with SBP. Furthermore, a lower prevalence of HTN (diagnosed by a physician) was observed in participants with higher intakes of protein. These results remained significant after adjustment for many covariates. However, significance was lost when kilocalories and micronutrients were included in the model.

CONCLUSIONS

Findings of the present study indicate that protein intake at lunch was independently and negatively associated with systolic BP in community-dwelling older adults.