Flavonoid intakes inversely associate with COPD in smokers

Effect of dietary phenolic compounds intake on mortality in the "Seguimiento Universidad De Navarra" (SUN) Mediterranean cohort

Plant-based dietary patterns have been demonstrated to reduce the risk of non-communicable disease (NCD), including cardiovascular disease (CVD), type 2 diabetes, cancer, and all-cause mortality. Phenolic compounds (PC), abundant in plant-based foods, have been considered as instrumental in this attenuation of NCD risk. We evaluated the association between dietary intake of PC and the risk of all-cause mortality in a relatively young Mediterranean cohort of 18,173 Spanish participants in the "Seguimiento Universidad de Navarra" (SUN) project, after a median follow-up of 12.7 years. Intake of PC was estimated at baseline and repeatedly after 10-year follow-up using a 136-item validated food frequency questionnaire and the Phenol-Explorer database. During 236,329 person-years, 544 deaths were confirmed. Cox regression models compared low intake (lowest quintile) vs. high intake (the four upper quintiles merged, as a reference category) of total energy-adjusted PC intake. Adjusted hazard ratios (HR) for low PC intake among those participants aged over 45 years during follow-up were 1.32; 95% CI 1.02-1.71 for all-cause mortality, HR:1.44; 95% CI 1.02-2.02 for cancer mortality; HR: 0.88; 95% CI 0.47-1.66 for CVD mortality and HR: 1.69 95% CI 1.04-2.74 for causes of death other than cancer or CVD. In conclusion, a low intake of total PC was associated with a significantly higher risk of all-cause mortality, and, specifically, a higher risk for cancer in a relatively young cohort. Among PC classes a low intake of flavonoids and phenolic acids showed significant effects for non-cancer/non-CVD mortality. Cherries, chocolate, apples and pears, olives, and coffee, were the major sources of between-person variability for total PC intake in our Mediterranean cohort.

Association between dietary flavonoids and childhood asthma

OBJECTIVE

Dietary flavonoids in various green plants have anti-inflammatory, antioxidant, and immune-modulating properties. While numerous studies have confirmed that flavonoid substances benefit asthma, evidence remains limited in epidemiological research and human experiments. This study aimed to explore the relationship between childhood asthma and dietary flavonoids.

METHODS

Dietary flavonoids comprise isoflavones, anthocyanins, flavan-3-ols, flavanones, flavones, and flavonols. This study used data from the United States National Health and Nutrition Examination Survey, collected during interviews from 2007 to 2010 and 2017 to 2018. Asthma data were obtained from the survey questionnaire. The analysis included 7,913 participants under 20 years old. A multivariable logistic regression model was performed to investigate the correlation between flavonoids (as constant or category variables) and asthma frequency among children in the United States, with stratified analyses performed for each group.

RESULTS

After adjusting for potential confounding variables, a significant negative correlation was observed between asthma incidence and the highest intake group of anthocyanins compared to the lowest intake group (odds ratio [OR] = 0.83, 95% confidence interval [CI]: 0.72-0.97, and p = 0.0182). Similarly, asthma incidence indicated a significant negative association with the median flavonol intake group compared to the lowest intake group (OR = 0.83, 95% CI: 0.72-0.97, and p = 0.0165). In the stratified analysis, anthocyanin content demonstrated a significant negative correlation with asthma prevalence among males, non-Hispanic whites, nonsmoking families, and middle-income families (p < 0.05).

CONCLUSION

The intake of dietary flavonoids, including anthocyanins and flavonols, is correlated with asthma prevalence in children.

Hypoglycemic and antioxidant activities of Jasminum officinale L. with identification and characterization of phytocompounds

The utilization of plant-derived chemicals with anti-diabetic properties is widely promoted for its advantageous tactics in managing diabetes, as they are cost-effective and have minimal or no adverse effects. Therefore, this work investigates the medicinal plant Jasminum officinale L. leaves by extraction and bio-guided fractionation. The ethyl acetate fraction showed a higher yield of 36.4 %. A phytochemical test on Jasminum officinale confirmed flavonoids, saponins, phenols, and tannins. The highest total phenol and flavonoid contents in the ethyl acetate fraction of J. officinale are 103.01 ± 1.1 mg GAE/g and 80.29 ± 1.03 mg QUE/ value found in methanol crude extract. Furthermore, HPTLC analysis of the ethyl acetate fraction detected the existence of flavonoids (kaempferol) and phenols (gallic acid, quercetin, and rutin). The compounds detected at the greatest concentrations in the LC-M/MS analysis of the ethyl acetate fraction were cirsiliol, kaempferol, and 2-tridecanone. Additionally, J. officinale (IC50 33.845 ± 1.09 μg/mL) demonstrated the highest DPPH scavenging activity in EAF like that of ascorbic acid (IC50 22.27 ± 0.96 μg/mL). Also, in the FRAP assay, the IC50 of this fraction is 15.14 ± 0.25 μM Fe equivalents. In the range of alpha-amylase deactivating action, from 13.25 % to 74.51 %, and IC50 value (47.40 ± 0.29 μg/mL) was significantly higher in the ethyl acetate fraction of J. officinale leaf extract. Moreover, J. officinale leaf extract had a substantially higher retention of glucose level (23.92 ± 0.85 % to 87.21 ± 0.6 %), significantly higher anti-inflammatory activity with the lowest IC50 value (66.00 ± 1.84), and lipid peroxidation (IC50 value 34.67 ± 1.69) by utilizing egg yolk as a substrate for lipids. Overall, the study revealed that J. officinale has considerable anti-diabetic characteristics. However, further comprehensive research is necessary to ascertain the medicinal purposes of J. officinale and its chemical components, pharmacological effects, and clinical uses.

Flavonoid intakes, chronic obstructive pulmonary disease, adult asthma, and lung function: a cohort study in the UK Biobank

BACKGROUND

Given their antioxidative stress, anti-allergic, anti-inflammatory, and immune-modulating effects, flavonoids are hypothesized to play a role in preventing chronic obstructive pulmonary disease (COPD) and asthma.

OBJECTIVES

This cohort study aimed to examine associations between flavonoid intake and COPD, asthma, and lung function.

METHODS

Among 119,466 participants of the UK Biobank, median [interquartile range] age of 60 [53, 65] y, we estimated intakes of flavonoids, flavonoid-rich foods, and a flavodiet score from 24-h diet assessments. Prospective associations with both incident COPD and asthma and cross-sectional associations with measures of lung function [%predicted forced expiratory volume in 1s (FEV1); and FEV1/forced vital capacity (FVC)] were examined using multivariable-adjusted Cox proportional hazards and linear regression models, respectively. We investigated mediation by inflammation--represented by the INFLA score--and stratified analyses by smoking status.

RESULTS

Compared with low intakes, moderate intakes of total flavonoids, flavonols, theaflavins + thearubigins, and flavanones, and moderate-to-high intakes of flavanol monomers, proanthocyanidins, anthocyanins, flavones, and the flavodiet score were associated with up to an 18% lower risk of incident COPD {e.g., [hazard ratio (95% confidence interval) for total flavonoids: 0.83 (0.75, 0.92)]} but not incident asthma. Furthermore, compared with low intakes, higher intakes of all flavonoid subclasses (except theaflavins + thearubigins), and the flavodiet score were associated with better percent predicted FEV1 baseline. Associations were most apparent in ever (current or former) smokers. Flavonoid intakes were inversely associated with the INFLA score, which appeared to mediate 11%-14% of the association between intakes of proanthocyanidins and flavones and incident COPD.

CONCLUSIONS

Moderate-to-high flavonoid intakes were associated with a lower risk of COPD and better lung function, particularly among ever smokers. Promoting intakes of healthy flavonoid-rich foods, namely, tea, apples, and berries, may improve respiratory health and lower COPD risk, particularly in individuals with a smoking history.

Association between dietary anthocyanin intake and chronic obstructive pulmonary disease in US adults: A public database survey

BACKGROUND

Anthocyanins have anti-inflammatory and antioxidant properties. Several studies have demonstrated that anthocyanins are associated with many chronic diseases, but few studies have focused on the relationship between anthocyanins and chronic obstructive pulmonary disease (COPD).

OBJECTIVES

This survey aimed to explore the relationship between dietary anthocyanin intake and COPD in US adults over the age of 40.

METHODS

A cross-sectional study from the National Health and Nutrition Examination Survey (NHANES) 2017-2018 was conducted. We used univariate and multivariate logistic regression and restricted cubic spline (RCS) to analyze the relationship between dietary anthocyanins and COPD. Subgroup and interaction analyses were adopted to assess whether there were differences in the relationship between dietary anthocyanin intake and COPD in different groups.

RESULTS

A total of 2862 participants aged ≥ 40 years were analyzed, of whom 213 were diagnosed with COPD. The highest tertile of dietary anthocyanin intake was negatively correlated with COPD compared to the lowest after adjusting potential confounders (Model 1, OR = 0.414; 95% CI: (0.245, 0.699), P-trend = 0.002; Model 2, OR = 0.363; 95% CI: (0.210, 0.627), P-trend = 0.002; Model 3, OR = 0.614; 95% CI: (0.383, 0.985), P-trend = 0.040). The RCS curve showed a significant inverse linear relationship between dietary anthocyanin intake and COPD (P non-linear = 0.734). In subgroup analyses, the negative correlation between dietary anthocyanin intake and COPD existed across different subgroups.

CONCLUSION

Our study indicated that higher dietary anthocyanins are a protective factor against the presence of COPD in the US aged over 40.

The Role of Nutrition in the Development and Management of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a prevalent lung condition associated with significant morbidity and mortality. The management of COPD classically involves pulmonary rehabilitation, bronchodilators, and corticosteroids. An aspect of COPD management that is currently lacking in the literature is nutritional management, despite the prevalence of inadequate nutritional status in patients with COPD. In addition, certain nutritional imbalances have been reported to increase the risk of COPD development. This review summarizes the current literature on the role diet and nutrients may play in the risk and management of COPD development.

Association of dietary flavonoid intakes with prevalence of chronic respiratory diseases in adults

BACKGROUND AND AIMS

Flavonoids are a class of secondary plant metabolites that have been shown to have multiple health benefits, including antioxidant and anti-inflammatory. This study was to explore the association between dietary flavonoid consumption and the prevalence of chronic respiratory diseases (CRDs) in adults.

METHODS AND RESULTS

The six main types of flavonoids, including isoflavones, anthocyanidins, flavan-3-ols, flavanones, flavones, and flavonols, were obtained from the National Health and Nutrition Examination Survey (NHANES) 2007-2010 and 2017-2018 by the two 24-h recall interviews. The prevalence of CRDs, including asthma, emphysema, and chronic bronchitis, was determined through a self-administered questionnaire. The analysis included 15,753 participants aged 18 years or older who had completed a diet history interview. After adjustment for potential confounders, the inverse link was found with total flavonoids, anthocyanidins, flavanones, and flavones, with an OR (95%CI) of 0.86 (0.75-0.98), 0.84 (0.72-0.97), 0.80(0.69-0.92), and 0.85(0.73-0.98) for the highest group compared to the lowest group. WQS regression revealed that the mixture of flavonoids was negatively linked with the prevalence of CRDs (OR = 0.88 [0.82-0.95], P < 0.01), and the largest effect was mainly from flavanones (weight = 0.41). In addition, we found that flavonoid intake was negatively linked with inflammatory markers, and systemic inflammation significantly mediated the associations of flavonoids with CRDs, with a mediation rate of 12.64% for CRP (P < 0.01).

CONCLUSION

Higher flavonoid intake was related with a lower prevalence of CRDs in adults, and this relationship may be mediated through systemic inflammation.

Associations of dietary copper intake with cardiovascular disease and mortality: findings from the Chinese Perspective Urban and Rural Epidemiology (PURE-China) Study

BACKGROUND

Previous in vitro and animal experiments have shown that copper plays an important role in cardiovascular health. Dietary copper is the main source of copper in the human body and the association between dietary copper and cardiovascular disease remains unclear. Our study aimed to investigate the associations of dietary copper intake with the risk of major cardiovascular disease incidence, cardiovascular disease mortality, and all-cause mortality in Chinese adults.

METHODS

Our study is based on Prospective Urban Rural Epidemiology China (PURE-China), a large prospective cohort study of 47 931 individuals aged 35-70 years from 12 provinces in China. Dietary intake was recorded using a validated semi-quantitative food frequency questionnaire designed specifically for the Chinese population. The daily intake of copper was obtained by multiplying the daily food intake with the nutrient content provided in the Chinese Food Composition Table (2002). Cox frailty proportional hazards models were developed to evaluate the association between dietary copper intake with mortality, major cardiovascular disease events, and their composite.

RESULTS

A total of 45 101 participants (mean age: 51.1 ± 9.7 years old) with complete information were included in the current study. The mean dietary copper intake was 2.6 ± 1.1 mg/d. During the 482 833 person-years of follow-up, 2 644(5.9%) participants died, 4 012(8.9%) developed new cardiovascular diseases, and 5 608(12.4%) participants experienced the composite endpoint. Compared with those in the first and second quartile of dietary copper intake, individuals in the third and fourth quantile had higher risk of composite outcomes, all-cause death, cardiovascular disease death, major cardiovascular disease and stroke occurrences. The associations remained similar in the subgroup and sensitivity analyses.

CONCLUSIONS

Our findings demonstrated that excessive dietary copper intake was associated with higher risks of death and cardiovascular diseases in Chinese adults. Further studies in populations with different dietary characteristics are needed to obtain dose-response relationships and to refine global dietary recommendations.

Association of Dietary Flavonoid Intake with Serum Cotinine Levels in the General Adult Population

Cotinine, the primary metabolite of nicotine, can be utilized as a marker for active smoking and as an indicator of exposure to secondhand smoke. However, the direct relationship between dietary flavonoid intake and serum cotinine levels remains a subject of ongoing investigation. In this study, we utilized data from the National Health and Nutrition Examination Survey (NHANES) 2007-2010 and 2017-2018 to assess the association between dietary flavonoid intake and serum cotinine levels in adults through multiple linear regression analysis. A weighted quantile sum (WQS) regression model was used to assess the association of the mixture of six dietary flavonoids with serum cotinine levels in adults, which could represent the overall effect of the mixture of six dietary flavonoids. We also conducted stratified analyses by smoke status to explore multiple linear regression associations between different flavonoid intake and serum cotinine levels. A total of 14,962 adults were included in the study. Compared to the group with the lowest dietary flavonoid intake, total flavonoid intake in the second (β = -0.29 [-0.44, -0.14]), third (β = -0.41 [-0.58, -0.24]), and highest groups (β = -0.32 [-0.49, -0.16]) was inversely related to the levels of serum cotinine after adjusting the full model. An RCS model showed that when the total dietary flavonoid intake was less than 99.61 mg/day, there was a negative linear association between dietary flavonoid intake and the serum cotinine. The WQS regression model also showed that the intake of a mixture of six dietary flavonoids was significantly negatively correlated with serum cotinine levels (β = -0.54 [-0.61, -0.46], p <0.01), with anthocyanins having the greatest effect (weights = 32.30%). Our findings imply a significant correlation between dietary flavonoid intake and serum cotinine levels among adults. The consumption of a combination of six dietary flavonoids was consistently linked to lower serum cotinine levels, with anthocyanins displaying the most pronounced impact.

Change in habitual intakes of flavonoid-rich foods and mortality in US males and females

BACKGROUND

Higher baseline intakes of flavonoid-rich foods and beverages are associated with a lower risk of chronic disease and mortality in observational studies. However, associations between changes in intakes and mortality remain unclear. We aimed to evaluate associations between 8-year changes in intakes of (1) individual flavonoid-rich foods and (2) a composite measure (termed the 'flavodiet') of foods and beverages that are known to be main contributors to flavonoid intake and subsequent total and cause-specific mortality.

METHODS

We evaluated associations between 8-year changes in intakes of (1) individual flavonoid-rich foods and (2) a novel 'flavodiet' score and total and cause-specific mortality. We included 55,786 females from the Nurses' Health Study (NHS) and 29,800 males from the Health Professionals Follow-up Study (HPFS), without chronic disease at baseline in our analyses. Using multivariable-adjusted Cox proportional hazard models, we examined associations of 8-year changes in intakes of (1) flavonoid-rich foods and (2) the flavodiet score with subsequent 2-year lagged 6-year risk of mortality adjusting for baseline intakes. Data were pooled using fixed-effects meta-analyses.

RESULTS

We documented 15,293 deaths in the NHS and 8988 deaths in HPFS between 1986 and 2018. For blueberries, red wine and peppers, a 5%, 4% and 9% lower risk of mortality, respectively, was seen for each 3.5 servings/week increase in intakes while for tea, a 3% lower risk was seen for each 7 servings/week increase [Pooled HR (95% CI) for blueberries; 0.95 (0.91, 0.99); red wine: 0.96 (0.93, 0.99); peppers: 0.91 (0.88, 0.95); and tea: 0.97 (0.95, 0.98)]. Conversely, a 3.5 servings/week increase in intakes of onions and grapefruit plus grapefruit juice was associated with a 5% and 6% higher risk of total mortality, respectively. An increase of 3 servings per day in the flavodiet score was associated with an 8% lower risk of total mortality [Pooled HR: 0.92 (0.89, 0.96)], and a 13% lower risk of neurological mortality [Pooled HR: 0.87 (0.79, 0.97)], after multivariable adjustments.

CONCLUSIONS

Encouraging an increased intake of specific flavonoid-rich foods and beverages, namely tea, blueberries, red wine, and peppers, even in middle age, may lower early mortality risk.

Associations of adherence to the DASH diet and the Mediterranean diet with chronic obstructive pulmonary disease among US adults

Background

The Dietary Approaches to Stop Hypertension (DASH) and the Mediterranean diet are associated with reduced cardiovascular, tumor, and diabetes risk, but the effect on chronic obstructive pulmonary disease (COPD) is uncertain.

Objective

To investigate the association of the DASH diet and the Mediterranean diet with the risk of COPD in American adults.

Methods

This cross-sectional study included 28,605 participants from the National Health and Nutrition Examination Survey (NHANES) 1999-2018 survey cycle who had complete dietary and other questionnaire data. The scores of healthy eating patterns (the DASH diet and the Mediterranean diet) were derived from a 24-h dietary recall interview [individual food and total nutrient data from NHANES and food pattern equivalents data from the United States Department of Agriculture (USDA)]. The primary outcome was the prevalence of COPD. COPD was defined based on participants self-reported whether or not a doctor or health professional had diagnosed chronic bronchitis or emphysema. Secondary outcomes were lung function and respiratory symptoms. All analyses were adjusted for demographics and standard COPD risk factors (primary tobacco exposure, secondhand smoke exposure, and asthma).

Results

This study included 2,488 COPD participants and 25,607 non-COPD participants. We found that a higher DASH diet score was associated with a lower risk of COPD [odds ratio (OR): 0.83; 95% confidence interval (CI): 0.71-0.97; P = 0.021]. This association persisted in several subgroups [men (OR: 0.73; 95% CI: 0.58-0.93; P = 0.010), relatively young (OR: 0.74; 95% CI: 0.55-1.01; P = 0.050), and smoker (OR: 0.82; 95% CI: 0.67-0.99; P = 0.038)]. In contrast, the Mediterranean diet score was not significantly associated with COPD prevalence in this large cross-sectional analysis representative of the US adult population (OR: 1.03; 95% CI: 0.88-1.20; P = 0.697). In addition, we found a correlation between DASH diet adherence and lung function [β: -0.01; 95% CI: -0.01-0.00; P = 0.003 (FEV1: FVC)] or respiratory symptoms [OR: 0.80; 95% CI: 0.73-0.89; P < 0.001 (dyspnea); OR: 0.80; 95% CI: 0.70-0.91; P = 0.002 (cough); OR: 0.86; 95% CI: 0.74-0.99; P = 0.042 (expectoration)], especially in non-COPD populations.

Conclusion

A higher DASH diet score was associated with improved COPD prevalence, lung function and respiratory symptoms. This new finding supports the importance of diet in the pathogenesis of COPD and expands the scope of the association of the DASH diet score with major chronic diseases.

Intake of dietary flavonoids and incidence of ischemic heart disease in the Danish Diet, Cancer, and Health cohort

BACKGROUND/OBJECTIVES

Few studies have investigated the association between dietary flavonoid intake, including all major subclasses, and the long-term risk of ischemic heart disease (IHD). We examined whether dietary flavonoid intake associated with IHD incidence, assessing the possible modifying role of sex and smoking, in participants from the Danish Diet, Cancer, and Health study.

SUBJECTS/METHODS

In a cohort study design, 54,496 adults (46.8% male), aged 50-64 years, without a history of IHD, were followed for up to 23 years. Habitual dietary flavonoid intake was estimated from food frequency questionnaires using Phenol-Explorer. Incident cases of IHD were identified within Danish nationwide health registries. Restricted cubic splines in Cox proportional hazards models were used to examine associations between flavonoid intake and IHD risk.

RESULTS

During follow-up, 5560 IHD events were recorded. No overall association was seen between total flavonoid intake, nor any subclass, and IHD, following adjustment for demographics, lifestyle, and dietary confounders. Stratified by sex and smoking status, higher intakes of specific subclasses associated with lower IHD risk among ever-smokers [Q5 vs. Q1 flavonols HR (95% CI): 0.90 (0.82, 0.99); flavanol oligo+polymers: 0.88 (0.80, 0.97)], but not among never-smokers, nor either sex specifically.

CONCLUSIONS

While we did not find clear evidence that higher habitual dietary flavonoid intake was associated with lower IHD risk, these results do not exclude the possibility that certain subclasses may have a protective role in prevention of IHD among population sub-groups; this was evident among smokers, who are at a higher risk of atherosclerosis.

The therapeutic potential of quercetin for cigarette smoking-induced chronic obstructive pulmonary disease: a narrative review

Quercetin is a flavonoid with antioxidant and anti-inflammatory properties. Quercetin has potentially beneficial therapeutic effects for several diseases, including cigarette smoking-induced chronic obstructive pulmonary disease (CS-COPD). Many studies have shown that quercetin's antioxidant and anti-inflammatory properties have positive therapeutic potential for CS-COPD. In addition, quercetin's immunomodulatory, anti-cellular senescence, mitochondrial autophagy-modulating, and gut microbiota-modulating effects may also have therapeutic value for CS-COPD. However, there appears to be no review of the possible mechanisms of quercetin for treating CS-COPD. Moreover, the combination of quercetin with common therapeutic drugs for CS-COPD needs further refinement. Therefore, in this article, after introducing the definition and metabolism of quercetin, and its safety, we comprehensively presented the pathogenesis of CS-COPD related to oxidative stress, inflammation, immunity, cellular senescence, mitochondrial autophagy, and gut microbiota. We then reviewed quercetin's anti-CS-COPD effects, performed by influencing these mechanisms. Finally, we explored the possibility of using quercetin with commonly used drugs for treating CS-COPD, providing a basis for future screening of excellent drug combinations for treating CS-COPD. This review has provided meaningful information on quercetin's mechanisms and clinical use in treating CS-COPD.