Effects of high- and low-isoflavone (phytoestrogen) soy foods on inflammatory biomarkers and proinflammatory cytokines in middle-aged men and women

Sex-specific pharmacokinetic response to phytoestrogens in Drosophila melanogaster

Drosophila melanogaster, or the fruit fly, is widely used for modeling numerous human diseases, such as neurodegeneration, tumor development, cachexia, and intestinal dysfunction. It is a suitable model organism for research targeting the physiology and pathophysiology of the intestinal epithelial barrier and has also been used as a model organism for preliminary drug and bioactive nutrient screening. However, the application of D. melanogaster in research on drug bioavailability and pharmacokinetic properties has not yet been well explored. In this study, we applied D. melanogaster to investigate the absorption and excretion of the orally administered phytoestrogens daidzein, glycitein, genistein, and their glycosides. Therefore, we established a quick, noninvasive method to quantify compound retention in D. melanogaster, suitable for the investigation of a broad variety of potentially bioactive substances. We showed that fruit fly sex plays a key role in the metabolization, transportation, and excretion of phytoestrogenic isoflavones. In particular, female fruit flies retained significantly more isoflavones than male fruit flies, which was reflected in the greater metabolic impact of isoflavones on females. Male fruit flies excreted more isoflavones than females did, which was linked to the upregulation of the xenobiotic transporter gene Mdr50. We also demonstrated that micellized isoflavones were more bioavailable than powdered isoflavones, independent of sex, age or the addition of dietary fibers.

Effect of the Fermented Soy Q-CAN® Product on Biomarkers of Inflammation and Oxidation in Adults with Cardiovascular Risk, and Canonical Correlations between the Inflammation Biomarkers and Blood Lipids

Systemic low-grade inflammation plays a key role in the development of cardiovascular disease (CVD) but the process may be modulated by consuming fermented soy foods. Here, we aim to evaluate the effect of a fermented soy powder Q-CAN^® on inflammatory and oxidation biomarkers in subjects with cardiovascular risk. In a randomized crossover trial, 27 adults (mean age ± SD, 51.6 ± 13.5 y) with a mean BMI ± SD of 32.3 ± 7.3 kg/m² consumed 25 g daily of the fermented soy powder or an isoenergic control powder of sprouted brown rice for 12 weeks each. Between-treatment results showed a 12% increase in interleukin-1 receptor agonist (IL-1Ra) in the treatment group, whereas within-treatment results showed 23% and 7% increases in interleukin-6 (IL-6) and total antioxidant status (TAS), respectively. The first canonical correlation coefficient (r = 0.72) between inflammation markers and blood lipids indicated a positive association between high-sensitivity C-reactive protein (hsCRP) and IL-1Ra with LDL-C and a negative association with HDL-C that explained 62% of the variability in the biomarkers. These outcomes suggest that blood lipids and inflammatory markers are highly correlated and that ingestion of the fermented soy powder Q-CAN^® may increase IL-1Ra, IL-6, and TAS in individuals with CVD risk factors.

The Isocaloric Substitution of Plant-Based and Animal-Based Protein in Relation to Aging-Related Health Outcomes: A Systematic Review

Plant-based and animal-based protein intake have differential effects on various aging-related health outcomes, but less is known about the health effect of isocaloric substitution of plant-based and animal-based protein. This systematic review summarized current evidence of the isocaloric substitutional effect of plant-based and animal-based protein on aging-related health outcomes. PubMed and Embase databases were searched for epidemiologic observational studies published in English up to 15 March 2021. Studies that included adults ≥18 years old; use of a nutritional substitution model to define isocaloric substitution of plant protein and animal protein; health outcomes covering mortality, aging-related diseases or indices; and reported association estimates with corresponding 95% confidence intervals were included. Nine cohort studies and 3 cross-sectional studies were identified, with a total of 1,450,178 subjects included in this review. Consistent and significant inverse association of substituting plant protein for various animal proteins on all-cause mortality was observed among 4 out of 5 studies with relative risks (RRs) from 0.54 to 0.95 and on cardiovascular disease (CVD) mortality among all 4 studies with RRs from 0.58 to 0.91. Among specific animal proteins, the strongest inverse association on all-cause and CVD mortality was identified when substituting plant protein for red and/or processed meat protein, with the effect mainly limited to bread, cereal, and pasta protein when replacing red meat protein. Isocaloric substitution of plant-based protein for animal-based protein might prevent all-cause and CVD-specific mortality. More studies are needed on this topic, particularly for cancer incidence and other specific aging-related diseases.

The effects of phytochemicals and herbal bio-active compounds on tumour necrosis factor-α in overweight and obese individuals: a clinical review

Obesity is abnormal fat accumulation in the body which acts as a risk factor for various cardiometabolic states. Adipose tissue in excess can release inflammatory factors, including TNF-α and IL-6, and suppress adiponectin production. TNF-α increases the levels of IL-6 and acute phase reactants such as C-reactive protein. Inflammation has a crucial role in developing and progressing various cardiometabolic diseases and a wide range of obesity-related complications. It has been shown that TNF-α has a significant role in the development of insulin resistance. Recently, a growing body of evidence has focused on herbal medicine, phytochemicals and natural bioactive compounds as inexpensive, relatively easy accessible agents with low adverse effects to reduce inflammatory markers such as TNF-α and simultaneously decrease insulin resistance, glucose intolerance, and dyslipidemia in obesity. The main focus of the current review is to summarize the results of the studies, which assessed the effects of phytochemicals and herbal bio-active compounds on serum TNF-α in subjects with overweight or obesity. This review suggests that herbal medicine have favorable effects on the reduction of TNF-α concentration; however, the results were not uniform for different products. Among the reviewed plants, ginger, ginseng, resveratrol, and flaxseed had more promising effects.

The Effects of Dietary Pattern on Metabolic Syndrome in Jiangsu Province of China: Based on a Nutrition and Diet Investigation Project in Jiangsu Province

Metabolic syndrome, a complex group of metabolic disorders of energy use and storage, is considered as an important determinant risk factor for many cardiovascular diseases. This study aimed to examine the association between metabolic syndrome (MetS) and dietary pattern among adults in Jiangsu Province of China. Data were from three rounds of cross–sectional nutrition and diet investigation projects in Jiangsu Province of China, which were conducted in 2002, 2007, and 2014 by Jiangsu Provincial Center for Disease Control and Prevention. A total of 13,944 participants with complete food frequency questionnaire (FFQ) were eventually included in this study after further data screening. The 2009 Joint Interim Statement for China was used to define metabolic syndrome. Three distinct dietary patterns were identified by factor analysis: the modern dietary pattern (rich in pork, poultry, vegetables, seafood, pastry food, other animal meats, fruits, milk and its products, soft drink, whole grains, nuts, and seeds, but low in wheat), vegetable oils/condiments/soy products dietary pattern (rich in vegetable oils, other condiments, salt, soy products, and fruits and low in dry legumes), and modern high–wheat dietary pattern (rich in wheat, tubers, fruits, and other animal meats, but low in rice). Higher intake of the modern dietary pattern and modern high–wheat dietary pattern were positively associated with metabolic syndrome in both unadjusted and adjusted models by genders, whereas higher intake of the vegetable oils/condiments/soy products dietary pattern had a negative relationship with metabolic syndrome in both unadjusted and adjusted models by genders (p < 0.05). Our study recommends reducing the consumption of animal meat products, especially processed meat products, and replacing animal oils with vegetable oils as the main supply of daily oils. Furthermore, more prospective and experimental studies are needed to confirm the relationship between dietary patterns and metabolic syndrome.

The Effects of Soy Products on Cardiovascular Risk Factors in Patients with Type 2 Diabetes: A Systematic Review and Meta-analysis of Clinical Trials

Previous studies have suggested that soy products may be beneficial for cardiometabolic health, but current evidence regarding their effects in type 2 diabetes mellitus (T2DM) remain unclear. The aim of this systematic review and meta-analysis was to determine the impact of soy product consumption on cardiovascular risk factors in patients with T2DM. PubMed, Scopus, Embase, and the Cochrane library were systematically searched from inception to March 2021 using relevant keywords. All randomized controlled trials (RCTs) investigating the effects of soy product consumption on cardiovascular risk factors in patients with T2DM were included. Meta-analysis was performed using random-effects models and subgroup analysis was performed to explore variations by dose and baseline risk profile. A total of 22 trials with 867 participants were included in this meta-analysis. Soy product consumption led to a significant reduction in serum concentrations of triglycerides (TG) (WMD: -24.73 mg/dL; 95% CI: -37.49, -11.97), total cholesterol (TC) (WMD: -9.84 mg/dL; 95% CI: -15.07, -4.61), low density lipoprotein (LDL) cholesterol (WMD: -6.94 mg/dL; 95% CI: -11.71, -2.17) and C-reactive protein (CRP) (WMD: -1.27 mg/L; 95% CI: -2.39, -0.16). In contrast, soy products had no effect on high density lipoprotein (HDL) cholesterol, fasting blood sugar (FBS), fasting insulin, hemoglobin A1c (HbA1c), homeostatic model assessment of insulin resistance (HOMA-IR), systolic and diastolic blood pressure (SBP/DBP) or body mass index (BMI) (all P ≥ 0.05). In subgroup analyses, there was a significant reduction in FBS after soy consumption in patients with elevated baseline FBS (>126 mg/dL) and in those who received higher doses of soy intake (>30 g/d). Moreover, soy products decreased SBP in patients with baseline hypertension (>135 mmHg). Our meta-analysis suggests that soy product consumption may improve cardiovascular parameters in patients with T2DM, particularly in individuals with poor baseline risk profiles. However, larger studies with longer durations and improved methodological quality are needed before firm conclusions can be reached.

Flavonoids against non-physiologic inflammation attributed to cancer initiation, development, and progression—3PM pathways

Inflammation is an essential pillar of the immune defense. On the other hand, chronic inflammation is considered a hallmark of cancer initiation and progression. Chronic inflammation demonstrates a potential to induce complex changes at molecular, cellular, and organ levels including but not restricted to the stagnation and impairment of healing processes, uncontrolled production of aggressive ROS/RNS, triggered DNA mutations and damage, compromised efficacy of the DNA repair machinery, significantly upregulated cytokine/chemokine release and associated patho-physiologic protein synthesis, activated signaling pathways involved in carcinogenesis and tumor progression, abnormal tissue remodeling, and created pre-metastatic niches, among others. The anti-inflammatory activities of flavonoids demonstrate clinically relevant potential as preventive and therapeutic agents to improve individual outcomes in diseases linked to the low-grade systemic and chronic inflammation, including cancers. To this end, flavonoids are potent modulators of pro-inflammatory gene expression being, therefore, of great interest as agents selectively suppressing molecular targets within pro-inflammatory pathways. This paper provides in-depth analysis of anti-inflammatory properties of flavonoids, highlights corresponding mechanisms and targeted molecular pathways, and proposes potential treatment models for multi-level cancer prevention in the framework of predictive, preventive, and personalized medicine (PPPM / 3PM). To this end, individualized profiling and patient stratification are essential for implementing targeted anti-inflammatory approaches. Most prominent examples are presented for the proposed application of flavonoid-conducted anti-inflammatory treatments in overall cancer management.

The efficacy of soy isoflavones combined with soy protein on serum concentration of interleukin-6 and tumour necrosis factor-α among post-menopausal women? A systematic review and meta-analysis of randomized controlled trials

The post-menopausal stage in women's life is associated with the enhancement of inflammation that may be reduced using soy isoflavones or soy protein. The present study aimed to summarize the effect of soy isoflavones plus soy protein on circulating interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) in post-menopausal women. The English-language articles were identified from the databases such as Cochrane Library, clinicaltrials.gov, Web of Science, PubMed, and Scopus until December 2020. The mean change from baseline and its standard deviation (SD) for intervention and comparison groups were used to calculate the effect size. The statistical heterogeneity of the intervention effects was computing by Cochran's Q test and I² statistic. Nine and seven studies were selected for systematic review and meta-analysis, respectively. The results of our meta-analysis indicated a non-significant effect on the serum concentrations of IL-6 and TNF-α (weighted mean differences [WMD] = 0.07 pg/mL; 95% confidence interval [CI] = -0.03, 0.17 pg/mL; P = 0.190; WMD =0.05 pg/mL; 95% CI = -0.01, 0.12 pg/mL; P = 0.092; respectively). In subgroup analysis, soy isoflavones plus soy protein could increase the serum concentration of IL-6 in studies with soy isoflavones dose ≤87 mg/days, cross-over design, weak quality, and studies on participants who had health risk factors or diseases. The serum concentration of TNF-α increased in studies with cross-over design, intervention duration ≤56 days, and body mass index (BMI) >27, and in studies that were conducted on at-risk or sick participants. In conclusion, our meta-analysis did not confirm any significant effect on serum concentration of IL-6 and TNF-α among post-menopausal women.

Beneficial effect of soy isoflavones and soy isoflavones plus soy protein on serum concentration of C-reactive protein among postmenopausal women: An updated systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Scientists suggest that soy isoflavones or the combination of soy isoflavones and soy protein may have beneficial effects on inflammation. Thus, the present study aims at conducting a systematic review and meta-analysis on randomized controlled trials (RCTs) in which the effect of soy isoflavones and the combination of soy isoflavones and soy protein on serum concentration of C-reactive protein (CRP) among postmenopausal women is assessed.

METHODS AND MATERIALS

A literature searching was done to identify a breadth of related references in PubMed, Scopus, ISI Web of Science, Cochrane Library, and Clinicaltrials.gov up to December 2020. The mean change from baseline in the CRP concentrations and its standard deviation (SD) for both intervention and comparison groups were used to calculate the effect size. The summary of the overall effects and heterogeneity was estimated by using the DerSimonian and Laird random effects model. The protocol was registered in PROSPERO (No. CRD42020166053).

RESULTS

This study considered 23 articles for systematic review and 19 articles for meta-analysis. The overall effect presented a non-significant effect of soy isoflavones on serum CRP concentrations (WMD = 0.08 mg/L, 95 % CI: -0.08, 0.24; p = 0.302) and the overall effect of the combination of soy isoflavones and soy protein indicated non-significant effect in serum levels of CRP (WMD= -0.02 mg/L 95 % CI: -0.12, 0.08; p = 0.715).

CONCLUSION

Published RCTs did not provide strong evidence regarding beneficial effect of soy isoflavones or the combination of soy isoflavones and soy protein on serum CRP concentration among postmenopausal women.

Can soy isoflavones plus soy protein change serum levels of interlukin-6? A systematic review and meta-analysis of randomized controlled trials

In the present review, we aimed to summarize the effect of soy isoflavones plus soy protein on circulating interlukin-6 (IL-6) in adult participants. Databases including ISI Web of Science, PubMed, Scopus, Cochrane Library, and clinicaltrials.gov were searched up to 23 March 2020. The mean change from baseline of IL-6 concentrations and its SD for intervention and comparison groups were used to calculate the effect size. If the heterogeneity test was statistically significant, DerSimonian and Laird random effects model was used. Cochran's Q test and I-squared statistic were also used to compute the statistical heterogeneity of the intervention's effects. Eighteen studies were known to be eligible for systematic review and 14 studies were selected for meta-analysis. Our meta-analysis results indicated a non-significant effect in serum IL-6 concentrations compared to the comparison group (WMD = 0.03 pg/ml, 95% CI: -0.06, 0.12; p = .459). In subgroup analysis, based on soy isoflavones dosage, it was observed that this combination could reduce IL-6 levels in studies that used isoflavones with dose >84 mg/day (WMD = -0.12 pg/ml 95% CI: -0.24, -0.004; p = .042, I2 = 82.7%) and in articles with a good quality (WMD = -0.15 pg/ml 95% CI: -0.24, -0.05; p = .003, I2 = 62.3%). Performing well-designed intervention studies using a high dose of soy isoflavones is recommended to confirm the beneficial effects of soy ingredients on IL-6.

The effect of soy isoflavones and soy isoflavones plus soy protein on serum concentration of tumor necrosis factor-α? A systematic review and meta-analysis of randomized controlled trials

In this study, we summarized the effect of soy isoflavones and soy isoflavones plus soy protein on serum concentration of tumor necrosis factor-alpha (TNF-α) among adult participants. We systematically searched Scopus, ISI Web of Science, Cochrane Library, PubMed, and clinicaltrials.gov for articles published up to May 2020. Effect size was calculated by mean change from baseline of TNF-α concentrations and its standard deviation (SD) for intervention and comparison groups. If the heterogeneity test was statistically significant, DerSimonian and Laird random effects model was used to estimate the summary of the overall effects and its heterogeneity. Nineteen and fourteen randomized clinical trials were included in our systematic review and meta-analysis, respectively. The result of overall effect size indicated a non-significant effect in serum concentration of TNF-α following soy isoflavones intake (WMD = 0.2 pg/ml, 95% CI: -0.13, 0.53; p = .226) and the combination of soy isoflavones and soy protein intake (WMD = 0.02 pg/ml, 95% CI: -0.02, 0.06; p = .286). Subgroup analyses revealed no significant change in circulatory levels of TNF-α following soy isoflavones plus soy protein intake. In conclusion, the present systematic review and meta-analysis found insufficient evidence that soy isoflavones or the combination of soy isoflavones and soy protein significantly reduce serum concentration of TNF-α.

Effects of soy intake on circulating levels of TNF-α and interleukin-6: a systematic review and meta-analysis of randomized controlled trials

PURPOSE

Pro-inflammatory mediators, including serum tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6), can be used as biomarkers to indicate or monitor disease. This study was designed to ascertain the effects of soy products on TNF-α and IL-6 levels.

METHODS

PubMed, EMBASE, Science Direct, Web of Science, Google Scholar and the Cochrane Central Register of Controlled Trials were searched to November 2019 for RCTs around the effects of soy-based products on TNF-α and IL-6. A random effects model was used to calculate overall effect size.

RESULTS

In total, 29 eligible publications were considered in the present systematic review, of which 25 were included in this meta-analysis. The overall effect of soy products on TNF-α and IL-6 levels failed to reach statistical significance (MD = - 0.07; 95% CI - 0.22-0.09; I² 50.9; MD = 0.03; 95% CI - 0.07-0.14; I² 42.1, respectively). According to a subgroup analysis, natural soy products led to a reduction in TNF-α concentration compared with processed soy products (MD = - 0.32; 95% CI - 0.45 to - 0.19; I² 0.0). Moreover, IL-6 reduction was stronger in participants who were affected by different diseases (MD = - 0.04; 95% CI - 0.07 to - 0.02; I² 0.0).

CONCLUSIONS

A review of RCTs published to November 2019 found that natural soy products are effective in lowering TNF-α levels. While the beneficial effects on reduction of IL-6 appeared stronger in individuals affected by different diseases, this finding cannot be generalized to all individuals affected by different diseases.

The effects of soy supplementation on inflammatory biomarkers: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Soy products contain several compounds with anti-inflammatory properties like genistein and daidzein which reported to act through different pathways. Present study conducted considering the inconsistent results and lack of any comprehensive review regarding randomized controlled trials which assess the effect of soy products on inflammatory markers.

METHODS

Following electronic databases were searched up to March 2020: PubMed, Scopus, ISI web of science, and Cochrane Library All randomized trials which assessed the effect of soy product supplementation on c-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) were included for last analysis. Treatment effects were expressed as mean difference (MD) and the standard deviation (SD) of outcomes. To estimate the overall effect the random-effects model was employed.

RESULTS

Finally, 51 randomized trial were included for present study. Last analysis showed that soy product supplementation lead to significant reduction in CRP (MD -0.27 mg/L; 95% CI: -0.51, -0.02, p = 0.028) but it did not affect IL-6 (MD 0.0 pg/ml; 95% CI: -0.06, 0.06, p = 0.970) and TNF-α (MD = -0.04 pg/ml; 95% CI: -0.11, 0.03, p = 0.252). Subgroup analysis showed that soy supplementation had a significant impact on decreasing IL-6 and TNF-α levels when studies had a long-term intervention (≥12 weeks) and used low dose isoflavone (<100 mg/day).

CONCLUSION

In conclusion, present systematic review and meta-analysis found a significant reduction in CRP levels after soy supplementation whiles IL-6 and TNF-α did not affect.

A Novel Cochlioquinone Derivative, CoB1, Regulates Autophagy in Pseudomonas aeruginosa Infection through the PAK1/Akt1/mTOR Signaling Pathway

Owing to multiple antibiotic resistance, Pseudomonas aeruginosa causes the most intractable infections to human beings worldwide, thus exploring novel drugs to defend against this bacterium remains of great importance. In this study, we purified a novel cochlioquinone B derivative (CoB1) from Salvia miltiorrhiza endophytic Bipolaris sorokiniana and reveal its role in host defense against P. aeruginosa infection by activating cytoprotective autophagy in alveolar macrophages (AMs) both in vivo and in vitro. Using a P. aeruginosa infection model, we observed that CoB1-treated mice manifest weakened lung injury, reduced bacterial systemic dissemination, decreased mortality, and dampened inflammatory responses, compared with the wild type littermates. We demonstrate that CoB1-induced autophagy in mouse AMs is associated with decreased PAK1 expression via the ubiquitination-mediated degradation pathway. The inhibition of PAK1 decreases the phosphorylation level of Akt, blocks the Akt/mTOR signaling pathway, and promotes the release of ULK1/2-Atg13-FIP200 complex from mTOR to initiate autophagosome formation, resulting in increased bacterial clearance capacity. Together, our results provide a molecular basis for the use of CoB1 to regulate host immune responses against P. aeruginosa infection and indicate that CoB1 is a potential option for the treatment of infection diseases.

The effect of soya consumption on inflammatory biomarkers: a systematic review and meta-analysis of clinical trials

Inflammation is a major cause of chronic diseases. Several studies have investigated the effects of soya intake on inflammatory biomarkers; however, the results are equivocal. The aim of this study was to conduct a systematic review and meta-analysis of clinical trials that evaluated the effect of soya consumption on inflammatory biomarkers. Medline, Scopus, ISI Web of Science and Google Scholar were systematically searched, up to and including May 2020, for clinical trials that evaluated the effects of soya and soya products on TNF-α, IL-6, IL-2, IL-1β and interferon γ (IFN-γ) in adults. A random effects method was used to calculate overall effects, and subgroup analyses were performed to discern probable sources of inter-study heterogeneity. A total of twenty-eight clinical trials were included. Although soya consumption reduced TNF-α (Hedges' g = -0·28; 95 % CI -0·49, -0·07), it had no significant effect on IL-6 (Hedges' g = 0·07, 95 % CI -0·14, 0·28), IL-2 (mean difference (MD) = -1·38 pg/ml; 95 % CI -3·07, 0·31), IL-1β (MD = -0·02 pg/ml; 95 % CI -0·08, 0·03) and IFN-γ (MD = 1685·82 pg/ml; 95 % CI -1604·86, 4976·50). Subgroup analysis illustrated a reduction in TNF-α in parallel designed studies, at dosages ≥100 mg of isoflavones, and in unhealthy subjects. The present study showed that high doses of isoflavones in unhealthy subjects may yield beneficial effects on TNF-α.

The effect of soy isoflavones on arterial stiffness: a systematic review and meta-analysis of randomized controlled trials

PURPOSE

Some but not all randomized controlled trials (RCTs) of soy isoflavones showed their beneficial effect on arterial stiffness, a predictor of cardiovascular events, dementia, and all-cause mortality, independent of traditional risk factors. To test the hypothesis that supplementation of soy isoflavones reduces arterial stiffness, we performed a systematic review and meta-analysis of RCTs of soy isoflavones on arterial stiffness.

METHODS

The protocol of this systematic review was registered with PROSPERO (CRD42019126128) and written in accordance with PRISMA. The PubMed, Embase, and clinicaltrials.gov databases were searched using the following criteria: human subjects, soy isoflavones as intervention, and arterial stiffness as primary outcome. A random-effects meta-analysis was used to pool estimates across studies. Standardized mean difference (SMD) was used to synthesize quantitative results.

RESULTS

Among 998 articles retrieved, 8 articles met our criteria. Duration of intervention was relatively short (maximum of 12 weeks). Outcome measurements extracted were pulse wave velocity (PWV), systemic arterial compliance (SAC), augmentation index (AI), and cardio-ankle vascular index (CAVI). Soy isoflavones reduced arterial stiffness compared to placebo (standardized mean difference - 0.33, 95% confidence interval - 0.47, - 0.19). Subgroup analyses showed no difference between treatment effects for intervention duration (< 6 weeks vs. ≥ 6 weeks) or gender (women only vs. men only vs. combined). Sensitivity analysis showed no difference in the effect of soy isoflavones between PWV, CAVI, SAC, and AI.

CONCLUSION

Supplementation of soy isoflavones reduced arterial stiffness. Longer duration trials with larger number of participants are warranted.

Effects of soy isoflavones on serum systemic and vascular inflammation markers and oxidative stress in peritoneal dialysis patients: A randomized controlled trial

Cardiovascular disease (CVD) is common in peritoneal dialysis (PD) patients. This study was designed to investigate the effects of isoflavones on systemic and vascular inflammation markers and oxidative stress in PD patients. In this randomized clinical trial, 40 PD patients were randomly assigned to either the isoflavone or the placebo group. The isoflavone group received 100 mg soy isoflavones daily for 8 weeks, whereas the placebo group received corresponding placebos. At baseline and the end of eighth week, serum high sensitive C-reactive protein (hs-CRP), intercellular adhesion molecule type 1 (ICAM-1), vascular cell adhesion molecule type 1 (VCAM-1), E-selectin, and malondialdehyde were measured. Serum VCAM-1 decreased significantly in the isoflavone group at the end of Week 8 compared to baseline (p = .01), whereas no significant change was observed in the placebo group. Serum ICAM-1 decreased significantly in the isoflavone (p = .01) and placebo (p = .01) group compared to baseline. However, the reduction of ICAM-1 was significantly higher in the isoflavone group than in the placebo group (p = .02). There were no significant differences between the two groups in mean changes of serum E-selectin, malondialdehyde, and hs-CRP. This study indicates that isoflavones reduce serum VCAM-1 and ICAM-1, which are two CVD risk factors, in PD patients.

Association of Soybean Food Intake and Cardiometabolic Syndrome in Korean Women: Korea National Health and Nutrition Examination Survey (2007 to 2011)

BACKGROUND

Soybean food consumption has been considered as a possible way to lower incidence of cardiometabolic syndrome (CMS) among Asians. However, results from studies investigating its efficacy on CMS in Asians have been inconsistent.

METHODS

We analyzed the association between soybean intake frequency and prevalence of CMS based on data from the Korea National Health and Nutrition Examination Survey 2007 to 2011. Data of 9,287 women aged 20 to 64 years were analyzed. Food frequency questionnaire was used to assess soybean food consumption frequency. General linear model and multivariable logistic regression model were used to examine the association of soybean intake quintile with CMS and its risk factors. Least square means of metabolic factors mostly showed no significant relevance except liver indexes.

RESULTS

Compared to participants in the 1st quintile (<2 times/week of soybean food), odds ratios (OR) for CMS and abdominal obesity (AO) in the 4th quintile (8.5 times/week<soybean food≤17 times/week) were 0.73 (95% confidence interval [CI], 0.57 to 0.95) and 0.72 (95% CI, 0.58 to 0.90), respectively. After excluding Tofu products, ORs of CMS, AO, high blood pressure, and hypertriglyceridemia were lower than those without excluding Tofu products. However, results still did not show significant inverse linear trend across frequency quintiles.

CONCLUSION

Our findings suggest that soybean intake of 8.5 to 17 times/week was inversely associated with CMS in Korean women. The relation between soybean intake >17 times/week and CMS varied depending on soybean food items.

A systematic review and meta-analysis of the effects of soy on serum hs-CRP

BACKGROUND & AIM

The results of studies about the effect of soy products on serum highly sensitive C-reactive protein (hs-CRP) are inconsistent. The aim of this systematic review and meta-analysis of randomized clinical trials (RCTs) was to investigate the effect of soy products intake on serum hs-CRP concentration.

METHODS

We searched PubMed, EMBASE, Science Direct, ISI Web of Science, Google Scholar and Cochrane Central Register of Controlled Trials up to December 2016 without language restrictions. Random-effect model was used for quantitative data synthesis.

RESULTS

Thirty-six studies were included in our analyses. A meta-analysis revealed a non-significant reduction in serum hs-CRP concentrations following soy products consumption, -0.19 (mg/L) (95% CI: -0.49 to 0.09; I2 = 95.6%). Subgroup analyses suggested that natural soya products may reduce plasma levels of CRP by -0.18 mg/L (95% CI: -0.28 to -0.08; I2: 11.6) in comparison to other source of isoflavones (soya extracts, supplements). Moreover, the effect was stronger among subjects with baseline hs-CRP concentrations of less than 2.52 mg/L, -0.15 (95% CI: -0.27 to -0.02; I2: 34.6). A meta-regression analysis revealed that dosage of isoflavones seems to be a strong predictor of the effect of soya on serum hs-CRP levels.

CONCLUSION

Present review of RCTs published up to December 2016 did not provide strong evidence regarding the beneficial effect of soya products consumption on blood hs-CRP concentrations. However, it appears that natural soya products may reduce plasma levels of hs-CRP in comparison to other source of isoflavones. Large and well-designed studies are recommended to confirm this conclusion.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42018069371.

Soy Isoflavones Ameliorate Metabolic and Immunological Alterations of Ovariectomy in Female Wistar Rats: Antioxidant and Estrogen Sparing Potential

Hormone replacement therapy (HRT) can alleviate estrogen deficiency symptoms especially during menopause. The present study aimed at investigating the effect of soy isoflavones as HRT on immunological and bone health-related parameters with a special focus on the interactions between immunological status and metabolism. Thirty healthy cyclic female Wistar rats were used in this experiment. Ten females were sham-operated, and 20 females were subjected to ovariectomy. Overiectomized (OVX) female rats were randomly divided into 2 groups: the control group (G1, OVX/casein) was fed a casein-based diet, and the second group (G2, OVX/soy) was fed a high soy isoflavone diet. Both groups were compared to a sham-operated group (G3, sham/casein). Treatments continued for 7 weeks. Feed intake, weight gain, and lymphoid organ relative weights were recorded. Some metabolic, immunological, and bone health-related parameters were measured. Moreover, nitric oxide (NO), malondialdehyde (MDA), and total antioxidant capacity (TAC) were determined. Bone histopathology and immunohistochemistry to estrogen receptor alpha (ERα) were done. Feeding soy to OVX females reduced feed intake, weight gain, relative lymphoid organ weight, and T-lymphocytes transformation. Soy isoflavone administration normalized nearly all metabolic and immunological parameters to a level comparable to the sham group via oxidative stress amelioration and bone ERα promotion. Soy isoflavones seemed to be good HRT in estrogen deprivation which modulated the appetite, weight gain, lipid profile, proinflammation, and bone turnover.

Associations between intake of dietary fermented soy food and concentrations of inflammatory markers: a cross-sectional study in Japanese workers

Epidemiological investigations have shown that consumption of soybeans or soy foods reduces the risk of the development of cardiovascular disease, cancer and osteoporosis. The aim of this study was to determine the associations between different soy foods and inflammatory markers, including high-sensitivity C-reactive protein (hs-CRP), interleukin (IL)-6, and IL-18, in Japanese workers. The cross-sectional study included 1,426 Japanese workers (1,053 men and 373 women) aged 20 to 64 years. Intake of 12 soy foods was estimated by a validated food frequency questionnaire. Associations of total soy foods, fermented soy food, non-fermented soy food, soy isoflavone with hs-CRP, IL-6, and IL-18 levels were examined by general linear model regression analysis. We found that total fermented soy food intake was inversely associated with multivariable-adjusted geometric concentration of IL-6 in men (Q1:1.03 pg/mL, Q5:0.94 pg /mL;P for trend = 0.031). Furthermore, it was shown that IL-6 concentrations were inversely associated with miso intake (β = -0.068;p = 0.034) and soy sauce intake in men (β = -0.074;p = 0.018). This study suggests that intake of total fermented soy food, miso and soy sauce be associated with IL-6 concentrations in Japanese men. J. Med. Invest. 65:74-80, February, 2018.

The impact of nuts consumption on glucose/insulin homeostasis and inflammation markers mediated by adiposity factors among American adults

BACKGROUND

Inconclusive results have been published regarding the impact of nut consumption on glucose/insulin homeostasis and inflammatory factors. Furthermore, it remains unanswered whether adiposity factors could mediate the association between nut consumption, glucose/insulin homeostasis and inflammatory markers; this is what the current study aims to investigate.

RESULTS

From a total of 16,784 individuals, 48.2% participants were men; overall mean age was 47.2 years. Age-, sex-, energy intake and race-adjusted mean of serum C-reactive protein (CRP)(0.49 to 0.26 mg/dl), apolipoprotein-β (apo- β) (95.6 to 90.8 mg/dl), glucose/insulin homeostasis parameters and triglyceride-glucose index (TyG) index (8.32 to 7.95) significantly decreased as the quartile of nut intake increased (all p < 0.001). We found that all evaluated potential mediators had significant and positive associations with markers of glucose/insulin homeostasis or inflammation (all p < 0.001). With regard to BMI, the mediated effects were significant for the associations between nut consumption and CRP, fasting blood glucose, insulin, hemoglobin A1c (HbA1c), triglyceride to high-density lipoprotein (TG:HDL) ratio and TyG index (all p < 0.001). As for WC, it had mediator impact on CRP, fasting blood glucose, HbA1c, TG:HDL ratio and TyG index (all p < 0.001). apVAT played no mediation role for any association (all p > 0.05).

CONCLUSIONS

This is the first study which quantify the role of nut consumption on inflammatory and glucose/insulin homeostasis markers. Nut intake was inversely associated with inflammatory and glucose/insulin homeostasis markers. Certain adiposity indexes (i.e. BMI and WC) mediated these associations. These findings convey an important message for the crucial role of weight management with dietary recommendations.

METHOD

We extracted data from the National Health and Nutrition Examination Survey (2005-2010) on nut consumption to evaluate the association between nut intake and markers of glucose/insulin homeostasis and inflammation. We assessed whether this link, if any, is mediated or affected by adiposity factors, including body mass index (BMI), waist circumference (WC, marker of central adiposity), anthropometrically predicted visceral adipose tissue (apVAT), visceral adiposity index (VAI, indicator of adipose distribution) and lipid accumulation product (LPA, novel index of central lipid accumulation). Analysis of co-variance and conceptus causal mediation analysis were conducted based on survey design and sample weights.

Comparing isolated soy protein with flaxseed oil vs isolated soy protein with corn oil and wheat flour with corn oil consumption on muscle catabolism, liver function, blood lipid, and sugar in burn patients: a randomized clinical trial

BACKGROUND

There is controversy regarding whether increasing isolated soy protein (ISP) with or without flaxseed oil (FO), as functional foods, would lead to reduce muscle catabolism and cachexia in burn patients.

METHODS

One hundred and eighty-eight patients were assessed for eligibility in this randomized controlled trial. Of these, seventy-three eligible patients (total burn surface area 20-50%) were randomly assigned to three groups, labeled as Control (wheat flour [WF] + corn oil [CO]), ISP + FO, and ISP + CO, to receive these nutrients for three weeks. Weight, body mass index (BMI), serum hepatic enzymes (alanine transaminase [ALT], aspartate transaminase [AST], alkaline phosphatase [ALP]), systemic inflammatory response syndrome (SIRS), 24-h urinary urea nitrogen excretion (UUN), serum creatinine, 24-h urinary creatinine (UUC) excretion, fasting blood sugar (FBS), triglyceride (TG), and cholesterol were measured.

RESULTS

Using analysis of covariance models in the intention-to-treat population (n = 73), we found that at three weeks, patients in the ISP groups had lost significantly less in weight and BMI compared to those in the control group (all P < 0.01). Nitrogen retention and serum creatinine (primary outcomes) increased significantly in the ISP groups compared with the control group. Even after controlling for potential covariates in ANCOVA models, changes in these indices were still statistically significant (P = 0.008 and P = 0.005 for nitrogen balance and serum creatinine, respectively). However, no such significant differences were found between the ISP groups. On the other hand, 24-h UUN, and UUC excretion, serum hepatic enzymes, FBS, TG, and cholesterol were not significant between the groups (P > 0.05).

CONCLUSION

ISP and FO compared to WF and CO reduced muscle catabolism and increased body weight in burn patients.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials, IRCT2014051817740N1 . Registered on 27 June 2014.

Antioxidants from diet or supplements do not alter inflammatory markers in adults with cardiovascular disease risk. A pilot randomized controlled trial

Antioxidants have been reported to have anti-inflammatory effects, but there is a lack of research comparing food to supplement antioxidant sources. The aim of this study was to determine if increases in intake of foods naturally rich in antioxidants would lower blood levels of inflammatory markers more than consuming antioxidant supplements among adults with cardiovascular disease risk factors. Eighty-eight generally healthy adults with ≥1 elevated risk factor for cardiovascular disease were randomized in a single-blind (diets)/double-blind (supplements), parallel-group study for 8 weeks. Participants consumed (1) usual diet and placebo pills (n = 29), (2) usual diet and antioxidant supplements (n = 29), or (3) antioxidant-rich foods closely matched to antioxidant content of supplements and placebo (n = 30). Usual diet combined with antioxidant supplements or increased antioxidant-rich food intake was designed to approximately double daily habitual antioxidant intake. Antioxidant pills included carotenoids, mixed tocopherols, vitamin C, and selenium. Fasting blood samples were analyzed for inflammatory marker concentrations of interleukin-6, monocyte chemotactic protein-1, and soluble intercellular adhesion molecule-1. Participants in the intervention groups successfully doubled most antioxidants as verified by diet records and elevated blood concentrations in treatment groups. Baseline levels of inflammatory markers for the entire study group were 110 ± 65 pg/mL for monocyte chemotactic protein-1, 0.9 ± 0.7 pg/mL for interleukin-6, and 217 ± 56 ng/mL for soluble intercellular adhesion molecule-1 (means ± standard deviation) and did not differ by treatment arm. After 8 weeks, there were no significant within-group changes or between-group 8-week change differences in inflammatory marker concentrations. In conclusion, no beneficial effects were detected on the inflammatory markers investigated in response to antioxidants from foods or supplements.

The history and basic science development of soy isoflavones

This review summarizes the 2016 NAMS/Pfizer-Wulf H. Utian Endowed Lecture that focused on the history and basic science of soy isoflavones. Described is a personal perspective of the background and history that led to the current interest in soy and isoflavones with a specific focus on the role that soy isoflavones play in the health of postmenopausal women. This overview covers the metabolism and physiological behavior of isoflavones, their biological properties that are of potential relevance to aging, issues related to the safety of soy isoflavones, and the role of the important intestinally derived metabolite S-(-)equol.

Soy Improves Cardiometabolic Health and Cecal Microbiota in Female Low-Fit Rats

Phytoestrogen-rich soy is known to ameliorate menopause-associated obesity and metabolic dysfunction for reasons that are unclear. The gut microbiota have been linked with the development of obesity and metabolic dysfunction. We aimed to determine the impact of soy on cardiometabolic health, adipose tissue inflammation, and the cecal microbiota in ovariectomized (OVX) rats bred for low-running capacity (LCR), a model that has been previously shown to mimic human menopause compared to sham-operated (SHM) intact control LCR rats. In this study, soy consumption, without affecting energy intake or physical activity, significantly improved insulin sensitivity and body composition of OVX rats bred for low-running capacity. Furthermore, soy significantly improved blood lipid profile, adipose tissue inflammation, and aortic stiffness of LCR rats. Compared to a soy-free control diet, soy significantly shifted the cecal microbial community of LCR rats, resulting in a lower Firmicutes:Bacteroidetes ratio. Correlations among metabolic parameters and cecal bacterial taxa identified in this study suggest that taxa Prevotella, Dorea, and Phascolarctobacterium may be taxa of interest. Our results suggest that dietary soy ameliorates adiposity, insulin sensitivity, adipose tissue inflammation, and arterial stiffness and exerts a beneficial shift in gut microbial communities in a rat model that mimics human menopause.

Impact of different types of tree nut, peanut, and soy nut consumption on serum C-reactive protein (CRP): A systematic review and meta-analysis of randomized controlled clinical trials

BACKGROUND

The effects of different types of tree nut, peanut, and soy nut consumption on serum C - reactive protein (CRP) are not well established. we aimed to undertake a systematic review and meta-analysis of prospective studies to determine the effect of nut consumption (tree nuts, peanuts, and soy nuts) on serum CRP.

METHOD

PubMed-Medline, Web of Science, Cochrane Database, and Google Scholar databases were searched (up until April 20 2016) to identify prospective studies evaluating the impact of tree nut, peanut, and soy nut consumption on serum CRP. Random effects models meta-analysis was used for quantitative data synthesis. Sensitivity analysis was conducted using the leave-one-out method. Heterogeneity was quantitatively assessed using the I index. Systematic review registration: CRD42016038044.

RESULTS

From a total of 844 entries identified via searches, 20 studies were included in the final selection. The meta-analysis indicated a nonsignificant increase in serum CRP concentrations following nut consumption (weighted mean difference [WMD] 0.17 mg/L, (95% CI -0.67 to 0.33, I 52.1%). The WMDs for IL6 was -0.06(ng/dL), (95% CI -0.69 to 0.56, I 9.6%), -0.71(mg/dL), (95% CI -1.11 to -0.30, I 6.3%), for leptin, and -0.60(mg/dL), (95% CI -1.88 to 0.68, I 5.6%) for adiponectin, and -0.18(mg/dL), (95% CI -1.24 to 0.88, I 9.3%) for IL10 and -0.37 (pg/mL), (95% CI -0.90 to 0.16, I 7.9%) for TNF-α. These findings were robust in sensitivity analyses.

CONCLUSIONS

This meta-analysis suggests that nut consumption significantly decrease leptin while have no significant effect on CRP, IL6, adiponectin, IL10, and TNF-α.

Inflammaging and Skeletal Muscle: Can Protein Intake Make a Difference?

Inflammaging is the chronic low-grade inflammatory state present in the elderly, characterized by increased systemic concentrations of proinflammatory cytokines. It has been shown that inflammaging increases the risk of pathologic conditions and age-related diseases, and that it also has been associated with increased skeletal muscle wasting, strength loss, and functional impairments. Experimental evidence suggests that the increased concentrations of proinflammatory cytokines and primary tumor necrosis factor α observed in chronic inflammation lead to protein degradation through proteasome activation and reduced skeletal muscle protein synthesis (MPS) via protein kinase B/Akt downregulation. Dairy and soy proteins contain all the essential amino acids, demonstrate sufficient absorption kinetics, and include other bioactive peptides that may offer nutritional benefits, in addition to those of stimulating MPS. Whey protein has antioxidative effects, primarily because of its ability to enhance the availability of reduced glutathione and the activity of the endogenous antioxidative enzyme system. Soy protein and isoflavone-enriched soy protein, meanwhile, may counteract chronic inflammation through regulation of the nuclear transcription factor κB signaling pathway and cytokine production. Although evidence suggests that whey protein, soy protein, and isoflavone-enriched soy proteins may be promising nutritional interventions against the oxidative stress and chronic inflammation present in pathologic conditions and aging (inflammaging), there is a lack of information about the anabolic potential of dietary protein intake and protein supplementation in elderly people with increased systemic inflammation. The antioxidative and anti-inflammatory effects, as well as the anabolic potential of protein supplementation, should be further investigated in the future with well-designed clinical trials focusing on inflammaging and its associated skeletal muscle loss.

Modulation of Toll-like receptor signaling in innate immunity by natural products

For centuries, natural products and their derivatives have provided a rich source of compounds for the development of new immunotherapies in the treatment of human disease. Many of these compounds are currently undergoing clinical trials, particularly as anti-oxidative, anti-microbial, and anti-cancer agents. However, the function and mechanism of natural products in how they interact with our immune system has yet to be extensively explored. Natural immune modulators may provide the key to control and ultimately defeat disorders affecting the immune system. They can either up- or down-regulate the immune response with few undesired adverse effects. In this review, we summarize the recent advancements made in utilizing natural products for immunomodulation and their important molecular targets, members of the Toll-like receptor (TLR) family, in the innate immune system.

Habitual dietary intake and mediators of the inflammaging process in Brazilian older women

AIM

This study aimed to assess whether the habitual intake of macronutrients by older women associates with circulating levels of important inflammaging mediators by means of a cross-sectional design with 229 Brazilian elderly women.

METHODS

Laboratory tests determined serum IL1α, IL1β, IL6, IL8, IL10, IL12 and TNFα by specific immunoassays. Food records of three alternate days were decomposed into usual intake of carbohydrates, proteins and lipids (and fractions), as well as total energy value (TEV) per patient. Moreover, the study has identified and controlled results for metabolic conditions known to influence the inflammatory profile: hypercholesterolemia, hypertension and diabetes.

RESULTS AND DISCUSSION

Pearson's correlation test revealed that log10IL8 expressed a positive association with levels of saturated fatty acid (FA) (r = 0.173; p = 0.009) and total cholesterol intake (r = 0.223; p = 0.001). Similar analysis of the other mediators revealed no association with dietary intake.

CONCLUSION

Higher intakes of total cholesterol and saturated FA seem to correlate with increased serum IL8 levels, being a possible mechanism by which this pro-atherogenic intake pattern may increase the risk of age-related chronic diseases with important inflammatory contribution.

Additive effects of isoflavones and exercise training on inflammatory cytokines and body composition in overweight and obese postmenopausal women: a randomized controlled trial

OBJECTIVE

Isoflavones and exercise have been shown to affect C-reactive protein (CRP) and body composition and to act synergistically on trunk and total fat mass (FM), glucose metabolism, and lean body mass in postmenopausal women with a body mass index higher than 25 kg/m. We hypothesized that exercise and isoflavone supplementation (Ex + ISO) could reduce inflammation in the same subpopulation of women. The objective of this study was to investigate if 6 months of mixed exercise combined with isoflavones could have greater effects on specific inflammatory markers than exercise alone in overweight or obese postmenopausal women.

METHODS

Thirty-four postmenopausal women aged 50 to 70 years were randomly assigned to exercise and placebo (Ex + PLA; n = 15) or Ex + ISO (n = 19). At baseline and after 6 months, waist circumference, hip circumference, total FM, trunk FM, leg FM, and muscle mass index (MMI; = total fat free mass [kg] / height [m]) were assessed (dual-energy x-ray absorptiometry). Inflammatory markers (CRP, tumor necrosis factor-α [TNF-α], and interleukin-6) were obtained by enzyme-linked immunosorbent assay. T tests were used to compare groups at baseline.

RESULTS

The Ex + PLA group showed significant changes in MMI (+0.33 kg/m, P ≤ 0.009) and FM compartments (waist circumference, -5.13 cm; % FM, -1.31%; P ≤ 0.001), whereas inflammation remained unchanged. However, the Ex + ISO group showed significant changes in total FM (-1.70 kg, P < 0.0001), FM compartments (hip circumference [-2.51 cm, P = 0.019], leg FM [-1.16 kg, P = 0.037], and trunk FM [-0.72 kg, P = 0.006]), MMI (+0.39 kg, P = 0.011), and inflammation (CRP, -1.14 mg/L, P = 0.029; TNF-α, +0.29 pg/mL, P = 0.010).

CONCLUSIONS

Despite an increase in TNF-α, the use of isoflavones-when body weight remains stable-seems to enhance the beneficial effects of mixed-exercise training on body composition and CRP in overweight or obese postmenopausal women.

Soy provides modest benefits on endothelial function without affecting inflammatory biomarkers in adults at cardiometabolic risk

SCOPE

Systemic inflammation, endothelial dysfunction, and oxidative stress are involved in the pathogenesis of the metabolic syndrome (MetS). Epidemiological evidence supports an association between whole soy food consumption and reduced risk of cardiovascular disease (CVD). The objective of this randomized, controlled, cross-over study was to evaluate the effects of soy nut consumption on inflammatory biomarkers and endothelial function and to assess whether isoflavone metabolism to secondary products, equol, and/or O-desmethylangolensin (ODMA), modifies these responses.

METHODS AND RESULTS

n = 17 adults at cardiometabolic risk were randomly assigned to the order of two snack interventions, soy nuts, and macronutrient-matched control snack, for four weeks each, separated by a two week washout period. Outcome measures included biomarkers of inflammation, oxidative stress, and glycemic control (ELISA and clinical analyzers), endothelial function, and arterial stiffness (peripheral arterial tonometry (PAT)), and isoflavone metabolites (LC-MS/MS). Results revealed that consuming soy nuts improved arterial stiffness as assessed by the augmentation index using PAT (p = 0.03), despite lack of improvement in inflammatory biomarkers. Addition of equol and/or ODMA production status as covariates did not significantly change these results.

CONCLUSION

Soy nuts when added to a usual diet for one month provide some benefit on arterial stiffness in adults at cardiometabolic risk.

The Effects of Probiotic Soymilk Fortified with Omega-3 on Blood Glucose, Lipid Profile, Haematological and Oxidative Stress, and Inflammatory Parameters in Streptozotocin Nicotinamide-Induced Diabetic Rats

OBJECTIVE

The aim of the present study was to evaluate the effects of probiotic soymilk fortified with omega-3 in diabetic rats.

METHODS

Soymilk (SM), fermented soymilk (FSM), and fermented soymilk fortified with omega-3 (FSM + omega-3) were prepared. Rats were randomly assigned to five groups of 13 animals per group. Diabetes was induced by a single injection of streptozotocin (STZ) 15 min after the intraperitoneal administration of nicotinamide (NA). Normal control (NC) and diabetic control (DC) rats received 1 mL/day of distilled water and three groups of diabetic rats were given 1 mL/day of SM, FSM, and FSM + omega-3 products by oral gavage for 28 days.

RESULTS

Three products significantly (P < 0.05) reduced blood glucose, total cholesterol (TC), triglyceride (TG), and malondialdehyde (MDA) concentrations compared to the DC group, with the maximum reduction seen in the FSM + omega-3 group. Body weight, red blood cells (RBC), haemoglobin (Hb), haematocrit, and superoxide dismutase (SOD) also significantly increased in the FSM + omega-3 group. In the FSM + omega-3 group, MDA level compared with the SM and FSM groups and high sensitivity C-reactive protein (hs-CRP) concentrations compared with the DC and FSM groups were significantly lower (P < 0.05).

CONCLUSION

Fermented soymilk fortified with omega-3 may be beneficial in diabetes.

Comparative effects of carbohydrate versus fat restriction on serum levels of adipocytokines, markers of inflammation, and endothelial function among women with the metabolic syndrome: a randomized cross-over clinical trial

BACKGROUND AND AIMS

Despite the efficacy of low-carbohydrate diets in the management of metabolic syndrome (MetS), it remains unknown if these favorable effects are mediated through changes in inflammation and endothelial dysfunction. We aimed to assess the effects of moderate substitution of dietary fats for carbohydrates on serum levels of adipocytokines, inflammatory indices, and biomarkers of endothelial function among women with the MetS.

METHODS

In a randomized cross-over clinical trial, 30 overweight or obese (BMI >25) women with the MetS were randomly allocated to follow either a high-carbohydrate (HC) (60-65% carbohydrates, 20-25% fats) diet or a moderately restricted carbohydrate (MRC) (43-47% carbohydrate, 36-40% fats) diet, each for 6 weeks. After a 2-week washout period, individuals were switched to the alternate diet for an additional 6 weeks. In a fasted state, markers of inflammation [high-sensitivity C-reactive protein (hs-CRP), high-sensitivity interleukin-6 (hs-IL-6), high-sensitivity tumor necrosis factor-α (hs-TNF-α), and serum amyloid A (SAA)], endothelial function [E-selectin, serum intercellular adhesion molecule 1 (sICAM-1), and serum vascular cell adhesion molecule 1 (sVCAM-1)], and adipocytokines (leptin and adiponectin) were measured in both study arms at baseline and after 6 weeks.

RESULTS

Consumption of an HC diet was associated with increased levels of SAA (3.27 ± 1.22 μg/ml) and decreased levels of adiponectin (-1.68 ± 2.30 ng/ml), while consumption of an MRC diet did not result in such unfavorable effects. Serum concentrations of leptin were reduced by the HC diet (p = 0.02), while they were not affected by the MRC diet. Changes in serum leptin levels were not significant between the two diets (p = 0.09). Serum concentrations of hs-CRP, hs-TNF-α, and IL-6 were not influenced by either diet. No significant differences between the two diets were found in terms of their effect on sICAM-1 and sVCAM-1 concentrations. Adherence to both diets resulted in a 9 ng/ml decrease in serum E-selectin levels (p < 0.05 for both).

CONCLUSIONS

Partial replacement of dietary carbohydrates by unsaturated fats prevents the increased levels of markers of systemic inflammation among women with the MetS.

Sex and inflammation in respiratory diseases: a clinical viewpoint

This review discusses sex differences in the prognosis of acute or chronic inflammatory diseases. The consequences of severe inflammation vary in relation to sex, depending on illness duration. In the majority of acute diseases, males present higher mortality rates, whereas continuous chronic inflammation associated with tissue damage is more deleterious in females. The recruitment of cells, along with its clinical expression, is more significant in females, as reflected by higher inflammatory markers. Given that estrogens or androgens are known to modulate inflammation, their different levels in males and females cannot account for the sexual dimorphism observed in humans and animals from birth to death with regard to inflammation. Numerous studies evaluated receptors, cytokine production, and clinical outcomes in both animals and humans, revealing that estrogens clearly modulate the immune response, but the results are contradictory and difficult to link to hormone concentrations. Even in prepubescent children, the presentation of acute pneumonia or chronic diseases mimics the adult pattern. Several genes located on the X chromosome have been shown to encode molecules involved in inflammation. Moreover, 10% to 15% of the genes from silenced X chromosome may escape inhibition. Females are also a mosaic of cells with genes from either paternal or maternal X chromosome. Therefore, polymorphism of X-linked genes would result in the presence of two cell populations with distinct regulatory arsenals, providing females with greater diversity to fight against infectious challenges, in comparison with the uniform cell populations in hemizygous males. The similarities observed between males and Turner syndrome patients using an endotoxin stimulation model support the difference in gene expression between monosomy and disomy for the X chromosome. Considering the enhanced inflammation in females, cytokine production may be assumed to be higher in females than males. Even if all results are not clear-cut, nonetheless, many studies have reported higher cytokine levels in both male humans and animals than in females. High IL-6 levels in males correlated with poorer prognosis and shorter longevity. A sound understanding of the basic regulatory mechanisms responsible for these gender differences may lead to new therapeutic targets.

Associations between urinary soy isoflavonoids and two inflammatory markers in adults in the United States in 2005-2008

PURPOSE

The aim of this study was to determine the association between urinary isoflavonoid (genistein, daidzein, and the daidzein metabolites O-desmethylangolensin (O-DMA) and equol) excretion and markers of inflammation in adults in the United States in National Health and Nutrition Examination Survey (NHANES) 2005-2008.

METHODS

The NHANES is a cross-sectional study conducted by the National Center for Health Statistics to study the health and nutritional status of people living in the United States. The analysis included 1,683 participants from study years 2005-2008 for whom urinary isoflavonoids were measured and who met inclusion criteria. Urinary isoflavonoids were measured by HPLC-APPI-MS/MS. Serum C-reactive protein (CRP) was measured by latex-based nephelometry. White blood cell (WBC) count was measured by Coulter counting. Multivariable linear regression was used to calculate the geometric mean values of the markers, and multivariable logistic regression was used to estimate the odds of high CRP (≥3 mg/L) and of high WBC count (≥7,900/μL) by quartile of urinary isoflavonoid (nmol/mg creatinine).

RESULTS

The highest quartile of genistein (OR = 0.62; 95 % CI 0.39-0.99) was associated with significantly decreased odds of high CRP compared with the lowest quartile. The sum of daidzein and its metabolites was significantly inversely associated with serum CRP concentration (p-trend = 0.017). Equol was inversely associated with WBC count (p-trend < 0.0001). O-DMA was the only isoflavonoid whose excretion was significantly associated with a decrease in both CRP (p-trend = 0.024) and WBC count (p-trend < 0.0001).

CONCLUSIONS

Though no clear pattern emerged, higher excretion of certain soy isoflavonoids was associated with decreased CRP concentration and WBC counts, suggesting a possible inverse association between soy intake and inflammation.

Habitual dietary isoflavone intake is associated with decreased C-reactive protein concentrations among healthy premenopausal women

Isoflavones have been associated with lower cardiovascular disease risk, but existing research focused on very high isoflavone intakes, as seen in Asian populations, as well as on risk factor reductions primarily in postmenopausal women. We investigated whether habitual low isoflavone intake among premenopausal women was associated with serum C-reactive protein (CRP) concentration, a commonly used biomarker associated with prediction of cardiovascular disease risk in healthy women. Between 2005 and 2007, 259 healthy, regularly menstruating women were enrolled in the BioCycle Study, and followed for up to 2 menstrual cycles. CRP was measured in serum at up to 16 clinic visits, timed to phases of the women's menstrual cycle. Diet was assessed up to 4 times per cycle by using 24-h recalls. Marginal structural models with inverse probability of exposure weights estimated the association between CRP and quartiles of isoflavone intake adjusted for age, race, BMI, cycle phase, total energy intake, total fiber, total whole grains, and phase-specific hormone concentrations including estradiol, progesterone, luteinizing hormone, and follicle-stimulating hormone. Compared with the lowest quartile of total isoflavone intake, women in the highest quartile had, on average, 27% lower serum CRP concentrations (95% CI: -35, -21%). Our results suggest that dietary isoflavone intakes at levels characteristic of the U.S. population are associated with decreased serum CRP concentrations, a factor associated with beneficial effects on inflammation, and subsequently may have the potential to improve health status among young women.

Effect of flavonoids on circulating levels of TNF-α and IL-6 in humans: a systematic review and meta-analysis

Epidemiological or in vitro evidence suggests a potential role for flavonoids as anti-inflammatory agents; we investigated the effect of flavonoids-rich foods or supplements on tumor necrosis factor- alpha (TNF-α) and interleukin-6 (IL-6) in long-term placebo-controlled human intervention trials. From 110 human intervention studies selected (MEDLINE, EMBASE, CHORANE, and FSTA databases), 32 long-term placebo-controlled trials were suitable for meta-analysis. After sensitivity analysis, seven studies imputed of bias were excluded and 25 studies were analyzed (TNF-α, n = 2404; IL-6, n = 2174). Levels of TNF-α decreased after flavonoid consumption in the fixed model only (mean difference (MD) (95% CI): -0.098 (-0.188, -0.009), p = 0.032), but metaregression results showed that neither higher dose, nor a longer duration of intervention were associated with a greater effect size. Subgroup analysis did not reveal any significant effect for quercetin and soy, but other sources (red wine, pomegranate, and tea extracts) showed a significant effect size both in fixed (MD (95% CI): TNF-α -0.449 (-0.619, -0.280), p < 0.001; IL-6 -0.346 (-0.612, -0.079), p = 0.011) and random (MD (95% CI): TNF-α -0.783 (-1.476, -0.090), p = 0.027; IL-6, -0.556 (-1.062, -0.050), p = 0.031) effect models. High-quality placebo-controlled trials are needed in order to identify flavonoids as the active ingredients.

Regulation of the immune response by soybean isoflavones

Soybeans are rich in immuno-modulatory isoflavones such as genistein, daidzein, and glycitein. These isoflavones are well-known antioxidants, chemopreventive and anti-inflammatory agents. Several epidemiological studies suggest that consumption of traditional soy food containing isoflavones is associated with reduced prevalence of chronic health disorders. Isoflavones are considered to be phytoestrogens because of their ability to bind to estrogen receptors. The literature is extensive on the chemistry, bio-availability, and bio-activity of isoflavones. However, their effects on immune response are yet to be fully understood, but are beginning to be appreciated. We review the role of isoflavones in regulation of the immune response and their potential clinical applications in immune-dysfunction. Special emphasis will be made regarding in vivo studies including humans and animal model systems.

The effects of isoflavones combined with soy protein on lipid profiles, C-reactive protein and cardiovascular risk among postmenopausal Chinese women

BACKGROUND & AIMS

Observational studies note that regular dietary soy protein intake (6-11 g day(-1)) has a significant association with lower blood lipids; however, these observations have not been confirmed by clinical trials. This study aimed to ascertain the effects of moderate intake of soy protein (15 g) with isoflavones or isoflavones alone on serum lipid profiles, inflammatory markers (C-reactive protein and uric acid) and composite cardiovascular risk in Chinese postmenopausal, prediabetic women.

METHODS AND RESULTS

A double-blind randomised, placebo-controlled trial was conducted among 180 postmenopausal Chinese women with prediabetes or early untreated diabetes, aged 46-70 years and, on average, 6.0 years since menopause. Participants were randomly assigned to one of the three arms to receive 15-g soy protein and 100-mg isoflavone (Soy group), or 15-g milk protein and 100 mg isoflavone (Iso group) or 15-g milk protein (placebo group) on a daily basis for 6 months. The results showed that no significant difference was observed in serum high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), total cholesterol (TC), triaclyglycerol (TG), high sensitive C-reactive protein and a composite 10-year cardiovascular risk between the three groups at both 3 and 6 months. Serum uric acid marginally increased by 1.22% in the Soy group and decreased by 4.28% and 4.82% in the Iso and placebo groups at 3 months (P = 0.087), but no difference was observed at 6 months (P = 0.264).

CONCLUSION

Soy protein with isoflavones or isoflavones alone at the provided dosage showed no significantly beneficial effects on measured cardiovascular risk factors in postmenopausal Chinese women with early hyperglycaemia.

Effect of exercise training combined with phytoestrogens on adipokines and C-reactive protein in postmenopausal women: a randomized trial

Phytoestrogens and training could be effective to reduce cardiovascular and type 2 diabetes mellitus risk factors in postmenopausal women. Nevertheless, the impact of their combination on adipokines and systemic inflammation was never investigated. The objective was to verify if 6 months of mixed training combined with phytoestrogens could have an additional effect on adipokine levels and systemic inflammation in obese postmenopausal women. Fifty-two obese women aged between 50 and 70 years were randomly assigned to (1) exercise with placebo (EX + PL; n = 25) or (2) exercise with phytoestrogens (EX + PHY; n = 27). Body weight, waist circumference, fat mass, and lean body mass (dual-energy x-ray absorptiometry) were assessed. Fasting plasma glucose and insulin, adiponectin, leptin, and C-reactive protein (CRP) levels were obtained after a 12-hour overnight fast. Total energy intake was measured with a 3-day dietary record. All measurements were performed before and after the 6-month intervention. Although energy intake remained unchanged, body composition was improved in all women (all Ps < .02). Plasma CRP and leptin levels decreased in both groups similarly (all Ps < .03), whereas plasma adiponectin and insulin did not change with exercise combined with placebo or phytoestrogens. Correlation analyses showed that homeostasis model assessment of insulin resistance (r = -0.58, P = .02) and fasting insulin levels (r = -0.42, P = .02) at baseline were both correlated with changes in leptin levels. Baseline fasting glucose (r = -0.36, P = .03) and adiponectin (r = 0.45, P = .005) levels were associated with changes in CRP concentrations. Although mixed exercise program combined with phytoestrogens does not seem to provide any additional effect, mixed training improves systemic inflammation and leptin concentrations in obese postmenopausal women.

Quercetin with vitamin C and niacin does not affect body mass or composition

In vitro and animal data suggest that quercetin affects adipogenesis and basal metabolism; however, whether this metabolic effect translates to reductions in body mass or improvement in body composition in humans is unknown. This study investigated 12-week supplementation of 2 different doses of quercetin, combined with vitamin C and niacin, on body mass and composition in a large, heterogeneous group of adults (n = 941; 60% female, 40% male; 18–85 years of age; 45% normal body mass index, 30% overweight, 25% obese). Subjects were randomized into 3 groups, with supplements administered in double-blind fashion: Q500 = 500 mg quercetin·day–1, Q1000 = 1000 mg quercetin·day–1, and placebo. Quercetin supplements were consumed twice daily over a 12-week period, and pre- and poststudy body mass and composition measurements were taken in an overnight fasted state. A general linear model was used to predict change in body mass and composition across groups with adjustment for demographic and lifestyle factors. Plasma quercetin increased in a dose-responsive manner in both Q500 and Q1000 groups relative to placebo. After adjustment for confounders, no significant differences in body mass (males interaction p value = 0.721, females p = 0.366) or body composition (males p = 0.650, females p = 0.639) were found between Q500 or Q1000 groups compared with placebo. No group differences in body mass or body composition were found in a subgroup of overweight and obese subjects. High-dose quercetin supplementation (500 and 1000 mg·day–1) for 12 weeks in a large, heterogeneous group of adults did not affect body mass or composition.

Selected dietary flavonoids are associated with markers of inflammation and endothelial dysfunction in U.S. women

Flavonoids show antiinflammatory effects in vitro and human intervention studies have suggested beneficial effects of flavonoid-rich foods on biomarkers of inflammation and endothelial function. In the present study, we assessed the relationship between flavonoid intake and biomarkers of inflammation and endothelial dysfunction in a cross-sectional study of participants from the Nurses' Health Study cohort. Intake of 6 flavonoid subclasses (flavonols, flavones, flavanones, flavan-3-ols, anthocyanidins, and polymeric flavonoids) was assessed using a FFQ administered in 1990. Also, the main food sources of these flavonoids were examined. Blood samples were collected in 1989-1990 and plasma C-reactive protein (CRP), IL-6, IL-18, soluble tumor necrosis factor receptor-2 (sTNF-R2), soluble intercellular adhesion molecule-1, soluble vascular adhesion molecule-1 (sVCAM-1), and E-selectin were measured in 1194-1598 women. The multivariate-adjusted geometric mean of plasma IL-8 were lower for women in the highest intake quintile of flavones, flavanones, and total flavonoids compared with those in the lowest quintiles by 9% (Q1: 264 ng/L, Q5: 241 ng/L; P-trend = 0.019), 11% (Q1: 273 ng/L, Q5: 244 ng/L; P-trend = 0.011), and 8% (Q1: 276 ng/L, Q5: 55 ng/L; P-trend = 0.034), respectively. The multivariate-adjusted geometric mean for women in the highest intake quintile of flavonol compared with those in the lowest quintile was 4% lower for sVCAM-1 (Q1: 578 μg/L, Q5: 557 μg/L; P-trend = 0.012). Among flavonoid-rich foods, higher intake of grapefruit was significantly associated with lower concentrations of CRP and sTNF-R2. In summary, higher intakes of selected flavonoid subclasses were associated with modestly lower concentrations of inflammatory biomarkers. In particular, flavonoids typically found in citrus fruits were modestly associated with lower plasma IL-18 concentrations.