Equol: history, chemistry, and formation

Antifungal activities of Equol against Candida albicans in vitro and in vivo

Candida albicans is an opportunistic fungal pathogen that can cause systemic infections in immunocompromised individuals. Morphological transition and biofilm formation are major virulence factors of C. albicans. Moreover, biofilm enhances resistance to antifungal agents. Therefore, it is urgent to identify new and effective compounds to target the biofilm of C. albicans. In the present study, the antifungal activities of equol against C. albicans were investigated. In vitro, the microdilution analysis and spot assay result showed that equol exhibited potent inhibitory activities against C. albicans. Further investigations confirmed that the antifungal effects of equol involved interference with the transition from yeast to hypha and biofilm formation of C. albicans. In addition, transcriptome sequencing and reverse transcription-quantitative PCR (qRT-PCR) analysis showed that equol significantly downregulated the expression of several genes in the Ras1-cAMP-PKA pathway related to hyphae and biofilm formation and significantly upregulated the expression of the negative transcriptional repressors RFG1 and TUP1. Moreover, equol effectively reduced the production of cAMP, a key messenger in the Ras1-cAMP-PKA pathway, while supplementation with cAMP partly rescued the equol-induced defects in hyphal development. Furthermore, in a mouse model of systemic candidiasis (SC), equol treatment significantly decreased the fungal burden (liver, kidneys, and lung) in mice and local tissue damage, while enhancing the production of interleukin-10 (IL-10). Together, these findings confirm that equol is a potentially effective agent for treatment of SC.

Rational design of short-chain dehydrogenase DHDR for efficient synthesis of (S)-equol

(S)-equol, the most influential metabolite of daidzein in vivo, has aroused great attention due to the excellent biological activities. Although existing studies have accomplished the construction of its heterologous synthetic pathway in the context of anaerobicity and inefficiency of natural strains, the low productivity of (S)-equol limits its industrial application. Here, rational design strategies based on decreasing the pocket steric hindrance and fine-tuning the pocket microenvironment to systematically redesign the binding pocket of enzyme were developed and processed to the rate-limiting enzyme dihydrodaidzein reductase in (S)-equol synthesis. After iterative combinatorial mutagenesis, an effective mutant S118G/T169A capable of significantly increasing (S)-equol yield was obtained. Computational analyses illustrated that the main reason of the increased activity relied on the decreased critical distance and more stable interacting conformation. Then, the reaction optimization was performed, and the recombinant Escherichia coli whole-cell biocatalyst harboring S118G/T169A enabled the efficient conversion of 2 mM daidzein to (S)-equol, achieving conversion rate of 84.5 %, which was 2.9 times higher than that of the parental strain expressing wide type dihydrodaidzein reductase. This study provides an effective idea and a feasible method for enzyme modification and whole-cell catalytic synthesis of (S)-equol, and will greatly accelerate the process of industrial production.

Effect of Fermented Soy Beverage on Equol Production by Fecal Microbiota

Soy consumption is associated with health benefits, mainly linked to the ability of the intestinal microbiota to metabolize the glycosylated isoflavones into more bioactive compounds, such as equol. Because Bifidobacterium pseudocatenulatum INIA P815 is able to efficiently deglycosylate daidzin into daidzein, the aim of this work was to confirm the influence of soy beverages fermented by B. pseudocatenulatum INIA P815 for enhancing equol production by fecal microbiota. Firstly, fecal samples from 17 participants were characterized in vitro, and we observed that 35.3% of them were able to produce equol from daidzein. In addition, the kinetics of equol production and degradation by fecal microbiota were evaluated, determining that 30-85% of equol is degraded after 24 h of incubation. Finally, the influence of fermented soy beverage on improving the production of equol by selected equol-producing fecal samples and by the equol-producing strain Slackia isoflavoniconvertens was analyzed through a colonic model. Fermented soy beverage enhanced the equol production from S. isoflavoniconvertens as well as the fecal samples whose microbiota showed high rates of equol degradation. The results obtained confirm that the fermentation of soy beverages with selected bacterial strains improves the functional properties of these beverages in terms of isoflavone metabolism and equol production.

Clinical effect of equol supplementation in the treatment of desquamative gingivitis with 1-year follow-up

PURPOSE

Desquamative gingivitis (DG) is characterized by desquamative erosion, edematous erythema, and vesicle formation on the gingiva. Because of its prevalence in women during the pre- and postmenopausal period, its potential association with female hormones has been suggested. Equol is a soy isoflavone metabolite with a chemical structure similar to estrogen. Scientific evidence suggests that equol helps in alleviating menopausal symptoms. This study evaluated the clinical effect of a 12-month equol supplementation as a substitute for estrogen to alleviate DG symptoms.

METHODS

The study enrolled 16 women with DG who regularly visited Nihon University School of Dentistry Dental Hospital. Urinary equol levels, periodontal tissue examination, O'Leary's plaque control record, stimulated saliva flow rate, and gingival pain-related questionnaires were evaluated before and after the 12-month daily intake of 10 mg equol supplement.

RESULTS

Equol supplementation led to a statistically significant improvement in bleeding on probing, visual findings, and reductions in the frequency and severity of gingival pain.

CONCLUSION

Urinary equol testing and equol supplementation may be novel treatment options for female patients with DG.

(R,S)-Equol 7-β-D-glucuronide, but not other circulating isoflavone metabolites, modulates migration and tubulogenesis in human aortic endothelial cells targeting the VEGF pathway

Current knowledge indicates that the consumption of isoflavone-rich foodstuffs can have a beneficial impact on cardiovascular health. To what extent these isoflavones act as the main actors of that benefit is less clear. Genistein (GEN), daidzein (DAZ), and the DAZ-derived microbial metabolite equol (Eq) exhibit antiangiogenic effects in vitro, but their low bloodstream concentrations make it difficult to rationalize the in vivo effects. Their derived phase-II metabolites (glucuronides and sulfates) are major metabolites found in plasma, but their role as antiangiogenic molecules remains unexplored. We aimed here to first assess the anti-angiogenic activities of the main circulating isoflavone metabolites (glucuronides and sulfates) and compare them with their corresponding free forms at physiological concentrations (0.1-10 μM). The effects of the conjugated vs. free forms on tubulogenesis, cell migration, and VEGF-induced signalling were investigated in primary human aortic endothelial cells (HAECs). While (R,S)-equol 7-β-D-glucuronide (Eq 7-glur) exerted dose-dependent inhibition of tubulogenesis and endothelial migration comparable to that exerted by the free forms (GEN, DAZ, and Eq), the rest of the phase-II conjugates exhibited no significant effects. The underlying molecular mechanisms were independent of the bFGF but related to the modulation of the VEGF pathway. Besides, the observed dissimilar cellular metabolism (conjugation/deconjugation) places the phase-II metabolites as precursors of the free forms; however, the question of whether this metabolism impacts their biological activity requires additional studies. These new insights suggest that isoflavones and their circulating metabolites, including Eq 7-glur, may be involved in cardiovascular health (e.g., targeting angiogenesis).

Equol: a metabolite of gut microbiota with potential antitumor effects

An increasing number of studies have shown that the consumption of soybeans and soybeans products is beneficial to human health, and the biological activity of soy products may be attributed to the presence of Soy Isoflavones (SI) in soybeans. In the intestinal tracts of humans and animals, certain specific bacteria can metabolize soy isoflavones into equol. Equol has a similar chemical structure to endogenous estradiol in the human body, which can bind with estrogen receptors and exert weak estrogen effects. Therefore, equol plays an important role in the occurrence and development of a variety of hormone-dependent malignancies such as breast cancer and prostate cancer. Despite the numerous health benefits of equol for humans, only 30-50% of the population can metabolize soy isoflavones into equol, with individual variation in gut microbiota being the main reason. This article provides an overview of the relevant gut microbiota involved in the synthesis of equol and its anti-tumor effects in various types of cancer. It also summarizes the molecular mechanisms underlying its anti-tumor properties, aiming to provide a more reliable theoretical basis for the rational utilization of equol in the field of cancer treatment.

Consumption of soya isoflavones improved polycystic ovary syndrome-associated metabolic disorders in a rat model

Polycystic ovary syndrome is associated with increased risks for certain metabolic disorders such as insulin resistance, non-alcoholic fatty liver disease and suppressed ovarian follicular development. This study aimed to examine whether soya isoflavones (ISF) mitigate these polycystic ovary syndrome-associated metabolic disorders in a rat model. Weanling Sprague-Dawley female rats were randomly divided into six groups and were treated with either 0 or 83 µg/d dihydrotestosterone (DHT) to induce polycystic ovary syndrome and fed diets containing 0, 0·5, or 1 g ISF/kg diet for 8 weeks. DHT treatment increased food intake, body weight gain (P < 0·001), percentage of primordial follicles (60 % v. 50·9 %, P < 0·05) and accumulation of lipid droplets in the livers. It also elevated serum total cholesterol, free cholesterol, TAG, NEFA and leptin and hepatic total cholesterol and NEFA. Additionally, DHT treatment reduced the percentage of primary follicles (13·8 % v. 30·2 %, P < 0·05), ovary weight and length (P < 0·001), as well as insulin sensitivity (P < 0·01) compared with the Control. ISF intake at 1 g/kg reduced body weight gain, serum total cholesterol, free cholesterol, NEFA, leptin and hepatic TAG and DHT-induced insulin resistance (P < 0·01). ISF intake at both levels decreased DHT-induced lipid droplet accumulation in the livers and changes in the percentages of primordial and primary follicles. Dietary soya ISF alleviated DHT-induced body weight gain, insulin resistance and hepatic lipid droplet accumulation, as well as suppressed ovarian follicular development. This suggests that the consumption of soya foods or ISF supplements may be beneficial for individuals with polycystic ovary syndrome, mitigating the associated metabolic disorders such as diabetes and non-alcoholic fatty liver disease.

Phytoestrogens: Chemistry, potential health benefits, and their medicinal importance

Phytoestrogens, also known as xenoestrogens, are secondary metabolites derived from plants that have similar structures and biological effects as human estrogens. These compounds do not directly affect biological functions but can act as agonists or antagonists depending on the level of endogenous estrogen in the body. Phytoestrogens may have an epigenetic mechanism of action independent of estrogen receptors. These compounds are found in more than 300 plant species and are synthesized through the phenylpropanoid pathway, with specific enzymes leading to various chemical structures. Phytoestrogens, primarily phenolic compounds, include isoflavonoids, flavonoids, stilbenes, and lignans. Extensive research in animals and humans has demonstrated the protective effects of phytoestrogens on estrogen-dependent diseases. Clinical trials have also shown their potential benefits in conditions such as osteoporosis, Parkinson's disease, and certain types of cancer. This review provides a concise overview of phytoestrogen classification, chemical diversity, and biosynthesis and discusses the potential therapeutic effects of phytoestrogens, as well as their preclinical and clinical development.

The cardiovascular toxicity of polystyrene microplastics in rats: based on untargeted metabolomics analysis

Background

Polystyrene microplastics (PS-MPs) exhibit multi-target, multi-dimensional, chronic, and low toxicity to the cardiovascular system. They enter the bloodstream through the gastrointestinal tract and respiratory system, altering blood parameters and conditions, inducing thrombotic diseases, and damaging myocardial tissue through the promotion of oxidative stress and inflammatory responses in myocardial cells. However, many of the links and mechanisms remain unclear.

Methods

In this study, 48 wistar rats were randomly divided into four groups and exposed to different concentrations of PS-MPs: control group (0 mg/kg/d), low dose group (0.5 mg/kg/d), middle dose group (5 mg/kg/d) and high dose group (50 mg/kg/d), with 12 rats in each group. After 90 consecutive days of intragastric administration of PS-MPs, biochemical markers in myocardium, aorta and blood were detected, and HE staining was performed to observe the toxic effects of PS-mps on cardiovascular system. Furthermore, non-targeted metabolomics methods were used to analyze the effect of PS-MPs exposure on the metabolism of cardiovascular system in rats, and to explore its potential molecular mechanism.

Results

The results revealed no pathological changes in the heart and aorta following PS-MPs exposure. However, the myocardial enzyme levels in the high dose PS-MPs group of rats showed a significant increase. Moreover, exposure to polystyrene microplastics caused a disorder in lipid metabolism in rats, and led to an increase in indicators of inflammation and oxidative stress in myocardial and aortic tissues, but resulted in a decrease in the level of IL-6. Untargeted metabolomics results showed that metabolites with antioxidant and anti-inflammatory effects, including equol and 4-hydroxybenzoic acid, were significantly upregulated.

Conclusion

These results suggest that long-term exposure to high concentrations of PS-MPs may lead to abnormal lipid metabolism and cardiovascular system damage. The mechanism may be related to oxidative stress and inflammatory response. Exogenous antioxidants and changes in own metabolites may have a protective effect on the injury. Therefore, understanding the toxicological mechanism of PS-MPs not only helps to elucidate its pathogenesis, but also provides new ideas for the treatment of chronic diseases.

EQUOL, A SOYBEAN METABOLITE WITH ESTROGEN-LIKE FUNCTIONS, DECREASES LIPOPOLYSACCHARIDE-INDUCED HUMAN NEUTROPHIL EXTRACELLULAR TRAPS IN VITRO

ABSTRACT

Objective: Neutrophil extracellular traps (NETs) defend against acute infections. However, their overexpression causes organ failure during sepsis. Control of NET formation may improve the outcomes of patients with sepsis. Equol, a soybean isoflavone, is a female hormone analog, which prevents inflammation. We evaluated the effects of equol on NET formation in human neutrophils during inflammatory stimulation in vitro . Methods: Healthy volunteers provided blood samples. An enzyme-linked immunosorbent assay assessed serum equol concentrations. Neutrophil extracellular trap formation in neutrophils was induced by lipopolysaccharide treatment. Enzyme-linked immunosorbent assay quantified DNA-binding elastase, and immunostaining assessed NET formation. Reverse-transcription quantitative polymerase chain reaction and Western blotting detected G-protein-coupled receptor 30 (GPR30) or peptidyl arginine deiminase 4 (PAD4) expression. Flow cytometry assessed neutrophil phagocytic ability with inactivated Escherichia coli . Results: In neutrophils derived from males with low-serum equol levels (low-serum equol group), equol significantly decreased DNA-binding elastase levels and NET formation. Equol did not decrease NETs in neutrophils from males with high-serum equol levels. GPR30 expression of neutrophils was higher in the low-serum than in the high-serum equol group. PAD4 mRNA levels and nuclear PAD4 protein expression also decreased more than the vehicle control in the low-serum equol group. Equol did not alter the phagocytic ability of neutrophils. In neutrophils from young females, equol had no inhibitory effect on NET formation. Conclusions: Equol decreases lipopolysaccharide-induced NET formation in neutrophils from males via inhibition of PAD4 expression. Our findings provide a rationale for investigating a new therapeutic approach using equol to control neutrophil activity during sepsis.

The gut microbiome as a modulator of arterial function and age-related arterial dysfunction

The arterial system is integral to the proper function of all other organs and tissues. Arterial function is impaired with aging, and arterial dysfunction contributes to the development of numerous age-related diseases, including cardiovascular diseases. The gut microbiome has emerged as an important regulator of both normal host physiological function and impairments in function with aging. The purpose of this review is to summarize more recently published literature demonstrating the role of the gut microbiome in supporting normal arterial development and function and in modulating arterial dysfunction with aging in the absence of overt disease. The gut microbiome can be altered due to a variety of exposures, including physiological aging processes. We explore mechanisms by which the gut microbiome may contribute to age-related arterial dysfunction, with a focus on changes in various gut microbiome-related compounds in circulation. In addition, we discuss how modulating circulating levels of these compounds may be a viable therapeutic approach for improving artery function with aging. Finally, we identify and discuss various experimental considerations and research gaps/areas of future research.

Mucin coated protein-polyphenol microcarriers for daidzein delivery

Daidzein, an isoflavone found abundantly in legumes, may benefit from bypassing upper gut absorption to reach the colon where it can be metabolized into the potent estrogen equol by the gut microbiome. To achieve this, we developed mucin coated protein-tannin multilayer microcarriers. Highly porous functionalized calcium carbonate (FCC) microparticles efficiently absorbed daidzein from a dimethyl sulfoxide solution, with a loading capacity of 21.6 ± 1.8 wt% as measured by ultra-high pressure liquid chromatography - mass spectrometry (UPLC-MS). Daidzein-containing FCC microparticles were then coated with a bovine serum albumin (BSA)-tannin n-layer film terminated with mucin ((BSA-TA)n-mucin) by layer-by-layer deposition from corresponding aqueous solutions followed by FCC decomposition with HCl. Raman spectroscopy confirmed mucin-tannin complexation involving both hydrophobic interactions and hydrogen bonding. The resulting multilayer microcarriers contained 54 wt% of nanocrystalline daidzein as confirmed by X-ray diffraction and UPLC-MS. Preliminary screening of several types of mucin coatings using an in vitro INFOGEST digestion model demonstrated that mucin type III from porcine stomach provided the highest protection against upper intestinal digestion. (BSA-TA)8-mucin and (BSA-TA)4-mucin microcarriers retained 71 ± 16.4% and 68 ± 4.6% of daidzein, respectively, at the end of the small intestinal phase. Mucin-free (BSA-TA)8 retained a lower daidzein amount of 46%. Daidzein release and further conversion into equol were observed during in vitro colonic studies with fecal microbiota from a healthy non-equol-producing donor and Slackia equolifaciens. The developed approach has potential for encapsulating other hydrophobic nutraceuticals or therapeutics, enhancing their bioaccessibility in the colon.

From Gut to Hormones: Unraveling the Role of Gut Microbiota in (Phyto)Estrogen Modulation in Health and Disease

The human gut microbiota regulates estrogen metabolism through the "estrobolome," the collection of bacterial genes that encode enzymes like β-glucuronidases and β-glucosidases. These enzymes deconjugate and reactivate estrogen, influencing circulating levels. The estrobolome mediates the enterohepatic circulation and bioavailability of estrogen. Alterations in gut microbiota composition and estrobolome function have been associated with estrogen-related diseases like breast cancer, enometrial cancer, and polycystic ovarian syndrome (PCOS). This is likely due to dysregulated estrogen signaling partly contributed by the microbial impacts on estrogen metabolism. Dietary phytoestrogens also undergo bacterial metabolism into active metabolites like equol, which binds estrogen receptors and exhibits higher estrogenic potency than its precursor daidzein. However, the ability to produce equol varies across populations, depending on the presence of specific gut microbes. Characterizing the estrobolome and equol-producing genes across populations can provide microbiome-based biomarkers. Further research is needed to investigate specific components of the estrobolome, phytoestrogen-microbiota interactions, and mechanisms linking dysbiosis to estrogen-related pathology. However, current evidence suggests that the gut microbiota is an integral regulator of estrogen status with clinical relevance to women's health and hormonal disorders.

The Promising Role of Polyphenols in Skin Disorders

The biochemical characteristics of polyphenols contribute to their numerous advantageous impacts on human health. The existing research suggests that plant phenolics, whether consumed orally or applied directly to the skin, can be beneficial in alleviating symptoms and avoiding the development of many skin disorders. Phenolic compounds, which are both harmless and naturally present, exhibit significant potential in terms of counteracting the effects of skin damage, aging, diseases, wounds, and burns. Moreover, polyphenols play a preventive role and possess the ability to delay the progression of several skin disorders, ranging from small and discomforting to severe and potentially life-threatening ones. This article provides a concise overview of recent research on the potential therapeutic application of polyphenols for skin conditions. It specifically highlights studies that have investigated clinical trials and the use of polyphenol-based nanoformulations for the treatment of different skin ailments.

Isoflavones Effects on Vascular and Endothelial Outcomes: How Is the Gut Microbiota Involved?

Isoflavones are a group of (poly)phenols, also defined as phytoestrogens, with chemical structures comparable with estrogen, that exert weak estrogenic effects. These phytochemical compounds have been targeted for their proven antioxidant and protective effects. Recognizing the increasing prevalence of cardiovascular diseases (CVD), there is a growing interest in understanding the potential cardiovascular benefits associated with these phytochemical compounds. Gut microbiota may play a key role in mediating the effects of isoflavones on vascular and endothelial functions, as it is directly implicated in isoflavones metabolism. The findings from randomized clinical trials indicate that isoflavone supplementation may exert putative effects on vascular biomarkers among healthy individuals, but not among patients affected by cardiometabolic disorders. These results might be explained by the enzymatic transformation to which isoflavones are subjected by the gut microbiota, suggesting that a diverse composition of the microbiota may determine the diverse bioavailability of these compounds. Specifically, the conversion of isoflavones in equol-a microbiota-derived metabolite-seems to differ between individuals. Further studies are needed to clarify the intricate molecular mechanisms behind these contrasting results.

Human Papillomavirus Infections and the Role Played by Cervical and Cervico-Vaginal Microbiota-Evidence from Next-Generation Sequencing Studies

This comprehensive review encompasses studies examining changes in the cervical and cervico-vaginal microbiota (CM and CVM) in relation to human papillomavirus (HPV) using next-generation sequencing (NGS) technology. HPV infection remains a prominent global health concern, with a spectrum of manifestations, from benign lesions to life-threatening cervical cancers. The CM and CVM, a unique collection of microorganisms inhabiting the cervix/vagina, has emerged as a critical player in cervical health. Recent research has indicated that disruptions in the CM and CVM, characterized by a decrease in Lactobacillus and the overgrowth of other bacteria, might increase the risk of HPV persistence and the progression of cervical abnormalities. This alteration in the CM or CVM has been linked to a higher likelihood of HPV infection and cervical dysplasia. NGS technology has revolutionized the study of the cervical microbiome, providing insights into microbial diversity, dynamics, and taxonomic classifications. Bacterial 16S rRNA gene sequencing, has proven invaluable in characterizing the cervical microbiome, shedding light on its role in HPV infections and paving the way for more tailored strategies to combat cervical diseases. NGS-based studies offer personalized insights into an individual's cervical microbiome. This knowledge holds promise for the development of novel diagnostic tools, targeted therapies, and preventive interventions for cervix-related conditions, including cervical cancer.

S-Dihydrodaidzein and 3-(1,3-benzoxazol-2-yl)-benzamide, Two New Potential β-estrogen Receptor Ligands with Anti-adipogenic Activity

BACKGROUND

The elucidation of molecular pathways associated with adipogenesis has evidenced the relevance of estrogen and estrogen receptor beta (ERβ). The positive effects of ERβ ligands on adipogenesis, energy expenditure, lipolysis, food intake, and weight loss, make ERβ an attractive target for obesity control. From ligand-based virtual screening, molecular docking, and molecular dynamic simulations, six new likely ERβ ligands (C1 to C6) have been reported with potential for pharmacological obesity treatment.

OBJECTIVE

In this study, the effect of molecules C1-C6 on adipogenesis using the murine 3T3-L1 cell line was evaluated.

METHODS

Cell viability was assessed by MTT assays. Lipid accumulation and gene expression were investigated by ORO staining and real-time quantitative RT-PCR experiments, respectively.

RESULTS

Cell viability was not significantly affected by C1-C6 at concentrations up to 10 μM. Interestingly, treatment with 10 μM of C1 (S-Dihydrodaidzein) and C2 (3-(1,3-benzoxazol-2-yl)- benzamide) for 72 h inhibited adipocyte differentiation; moreover, ORO staining evidenced a reduced intracellular lipid accumulation (40% at day 7). Consistently, mRNA expression of the adipogenic markers, PPARγ and C/EBPα, was reduced by 50% and 82%, respectively, in the case of C1, and by 83% and 59%, in the case of C2.

CONCLUSION

Altogether, these results show the two new potential β-estrogen receptor ligands, C1 and C2, to exhibit anti-adipogenic activity. They could further be used as lead structures for the development of more efficient drugs for obesity control.

Indole-3-acetic acid alleviates DSS-induced colitis by promoting the production of R-equol from Bifidobacterium pseudolongum

BACKGROUND

Inflammatory bowel disease (IBD) is characterized by immune-mediated, chronic inflammation of the intestinal tract. The occurrence of IBD is driven by the complex interactions of multiple factors. The objective of this study was to evaluate the therapeutic effects of IAA in colitis.

METHOD

C57/BL6 mice were administered 2.5% DSS in drinking water to induce colitis. IAA, Bifidobacterium pseudolongum, and R-equol were administered by oral gavage and fed a regular diet. The Disease Activity Index was used to evaluate disease activity. The degree of colitis was evaluated using histological morphology, RNA, and inflammation marker proteins. CD45+ CD4+ FOXP3+ Treg and CD45+ CD4+ IL17A+ Th17 cells were detected by flow cytometry. Analysis of the gut microbiome in fecal content was performed using 16S rRNA gene sequencing. Gut microbiome metabolites were analyzed using Untargeted Metabolomics.

RESULT

In our study, we found IAA alleviates DSS-induced colitis in mice by altering the gut microbiome. The abundance of Bifidobacterium pseudolongum significantly increased in the IAA treatment group. Bifidobacterium pseudolongum ATCC25526 alleviates DSS-induced colitis by increasing the ratio of Foxp3+T cells in colon tissue. R-equol alleviates DSS-induced colitis by increasing Foxp3+T cells, which may be the mechanism by which ATCC25526 alleviates DSS-induced colitis in mice.

CONCLUSION

Our study demonstrates that IAA, an indole derivative, alleviates DSS-induced colitis by promoting the production of Equol from Bifidobacterium pseudolongum, which provides new insights into gut homeostasis regulated by indole metabolites other than the classic AHR pathway.

Effect of Soy Protein Supplementation on Muscle Adaptations, Metabolic and Antioxidant Status, Hormonal Response, and Exercise Performance of Active Individuals and Athletes: A Systematic Review of Randomised Controlled Trials

BACKGROUND

Protein supplements are important to maintain optimum health and physical performance, particularly in athletes and active individuals to repair and rebuild their skeletal muscles and connective tissues. Soy protein (SP) has gained popularity in recent years as an alternative to animal proteins.

OBJECTIVES

This systematic review evaluates the evidence from randomised controlled clinical trials of the effects of SP supplementation in active individuals and athletes in terms of muscle adaptations, metabolic and antioxidant status, hormonal response and exercise performance. It also explores the differences in SP supplementation effects in comparison to whey protein.

METHODS

A systematic search was conducted in PubMed, Embase and Web of Science, as well as a manual search in Google Scholar and EBSCO, on 27 June 2023. Randomised controlled trials that evaluated the applications of SPs supplementation on sports and athletic-related outcomes that are linked with exercise performance, adaptations and biomarkers in athletes and physically active adolescents and young adults (14 to 39 years old) were included, otherwise, studies were excluded. The risk of bias was assessed according to Cochrane's revised risk of bias tool.

RESULTS

A total of 19 eligible original research articles were included that investigated the effect of SP supplementation on muscle adaptations (n = 9), metabolic and antioxidant status (n = 6), hormonal response (n = 6) and exercise performance (n = 6). Some studies investigated more than one effect. SP was found to provide identical increases in lean mass compared to whey in some studies. SP consumption promoted the reduction of exercise-induced metabolic/blood circulating biomarkers such as triglycerides, uric acid and lactate. Better antioxidant capacity against oxidative stress has been seen with respect to whey protein in long-term studies. Some studies reported testosterone and cortisol fluctuations related to SP; however, more research is required. All studies on SP and endurance performance suggested the potential beneficial effects of SP supplementation (10-53.3 g) on exercise performance by improving high-intensity and high-speed running performance, enhancing maximal cardiac output, delaying fatigue and improving isometric muscle strength, improving endurance in recreational cyclists, increasing running velocity and decreasing accumulated lactate levels; however, studies determining the efficacy of soy protein on VO2max provided conflicted results.

CONCLUSION

It is possible to recommend SP to athletes and active individuals in place of conventional protein supplements by assessing their dosage and effectiveness in relation to different types of training. SP may enhance lean mass compared with other protein sources, enhance the antioxidant status, and reduce oxidative stress. SP supplementation had an inconsistent effect on testosterone and cortisol levels. SP supplementation may be beneficial, especially after muscle damage, high-intensity/high-speed or repeated bouts of strenuous exercise.

Effect of soy isoflavones on C-reactive protein in chronic inflammatory disorders

New evidence suggests that soy products might reduce chronic systemic inflammation. Therefore, we aimed to summarize the effect of soy isoflavones on serum concentration of C-reactive protein (CRP) among participants with chronic inflammatory disorders by conducting this study. Cochrane Library, Scopus, ISI Web of Science, clinicaltrials.gov, and PubMed were searched to identify randomized clinical trials (RCTs) published up to December 2020. The effect size was calculated by the mean change from baseline in concentrations of CRP and its standard deviation for both intervention and comparison groups. DerSimonian and Laird random-effects model was used when the heterogeneity test was statistically significant. In total, thirteen RCTs involving 1213 participants and ten RCTs involving 1052 participants were eligible for our systematic review and meta-analysis respectively. Study duration ranged from 4 to 96 weeks and soy isoflavones dose varied from 33 to 132 mg/day. Overall effect size indicated a non-significant effect on serum concentration of CRP following soy isoflavones intake (weighted mean differences (WMD)=-0.15 mg/L, 95% confidence interval (CI): -0.54, 0.23; p=0.430). Subgroup analysis revealed that soy isoflavones significantly reduced serum concentration of CRP in studies among participants with age >57 years and baseline CRP levels >3.75 mg/L. The present study proposed that soy isoflavones could not significantly reduce serum CRP levels. It seems more RCTs on participants with age more than 57 years and higher levels of CRP is necessary.

A New Paradigm in the Relationship between Gut Microbiota and Breast Cancer: β-glucuronidase Enzyme Identified as Potential Therapeutic Target

Breast cancer (BC) is the most frequently occurring malignancy and the second cancer-specific cause of mortality in women in developed countries. Over 70% of the total number of BCs are hormone receptor-positive (HR+), and elevated levels of circulating estrogen (E) in the blood have been shown to be a major risk factor for the development of HR+ BC. This is attributable to estrogen's contribution to increased cancer cell proliferation, stimulation of angiogenesis and metastasis, and resistance to therapy. The E metabolism-gut microbiome axis is functional, with subjacent individual variations in the levels of E. It is conceivable that the estrobolome (bacterial genes whose products metabolize E) may contribute to the risk of malignant neoplasms of hormonal origin, including BC, and may serve as a potential biomarker and target. It has been suggested that β-glucuronidase (GUS) enzymes of the intestinal microbiome participate in the strobolome. In addition, it has been proposed that bacterial GUS enzymes from the gastrointestinal tract participate in hormone BC. In this review, we discuss the latest knowledge about the role of the GUS enzyme in the pathogenesis of BC, focusing on (i) the microbiome and E metabolism; (ii) diet, estrobolome, and BC development; (iii) other activities of the bacterial GUS; and (iv) the new molecular targets for BC therapeutic application.

The Role of Choline, Soy Isoflavones, and Probiotics as Adjuvant Treatments in the Prevention and Management of NAFLD in Postmenopausal Women

Nonalcoholic fatty liver disease (NAFLD) is a prevalent condition among postmenopausal women that can lead to severe liver dysfunction and increased mortality. In recent years, research has focused on identifying potential lifestyle dietary interventions that may prevent or treat NAFLD in this population. Due to the complex and multifactorial nature of NAFLD in postmenopausal women, the disease can present as different subtypes, with varying levels of clinical presentation and variable treatment responses. By recognizing the significant heterogeneity of NAFLD in postmenopausal women, it may be possible to identify specific subsets of individuals who may benefit from targeted nutritional interventions. The purpose of this review was to examine the current evidence supporting the role of three specific nutritional factors-choline, soy isoflavones, and probiotics-as potential nutritional adjuvants in the prevention and treatment of NAFLD in postmenopausal women. There is promising evidence supporting the potential benefits of these nutritional factors for NAFLD prevention and treatment, particularly in postmenopausal women, and further research is warranted to confirm their effectiveness in alleviating hepatic steatosis in this population.

Beneficial effects of phenolic compounds: native phenolic compounds vs metabolites and catabolites

In the human body, the positive effects of phenolic compounds are increasingly observed through their presence in tissues and organs in their native form or in the form of metabolites or catabolites formed during digestion, microbial metabolism, and host biotransformation. The full extent of these effects is still unclear. The aim of this paper is to review the current knowledge of beneficial effects of native phenolic compounds or their metabolites and catabolites focusing on their role in the health of the digestive system, including disorders of the gastrointestinal and urinary tracts and liver. Studies are mostly connecting beneficial effects in the gastrointestinal and urinary tract to the whole food rich in phenolics, or to the amount of phenolic compounds/antioxidants in food. Indeed, the bioactivity of parent phenolic compounds should not be ignored due to their presence in the digestive tract, and the impact on the gut microbiota. However, the influence of their metabolites and catabolites might be more important for the liver and urinary tract. Distinguishing between the effects of parent phenolics vs metabolites and catabolites at the site of action are important for novel areas of food industry, nutrition and medicine.

Digital Database of Absorption Spectra of Diverse Flavonoids Enables Structural Comparisons and Quantitative Evaluations

Flavonoids play diverse roles in plants, comprise a non-negligible fraction of net primary photosynthetic production, and impart beneficial effects in human health from a plant-based diet. Absorption spectroscopy is an essential tool for quantitation of flavonoids isolated from complex plant extracts. The absorption spectra of flavonoids typically consist of two major bands, band I (300-380 nm) and band II (240-295 nm), where the former engenders a yellow color; in some flavonoids the absorption tails to 400-450 nm. The absorption spectra of 177 flavonoids and analogues of natural or synthetic origin have been assembled, including molar absorption coefficients (109 from the literature, 68 measured here). The spectral data are in digital form and can be viewed and accessed at http://www.photochemcad.com. The database enables comparison of the absorption spectral features of 12 distinct types of flavonoids including flavan-3-ols (e.g., catechin, epigallocatechin), flavanones (e.g., hesperidin, naringin), 3-hydroxyflavanones (e.g., taxifolin, silybin), isoflavones (e.g., daidzein, genistein), flavones (e.g., diosmin, luteolin), and flavonols (e.g., fisetin, myricetin). The structural features that give rise to shifts in wavelength and intensity are delineated. The availability of digital absorption spectra for diverse flavonoids facilitates analysis and quantitation of these valuable plant secondary metabolites. Four examples are provided of calculations─multicomponent analysis, solar ultraviolet photoprotection, sun protection factor (SPF), and Förster resonance energy transfer (FRET)─for which the spectra and accompanying molar absorption coefficients are sine qua non.

Effects of Equol Supplementation on Growth Performance, Redox Status, Intestinal Health and Skeletal Muscle Development of Weanling Piglets with Intrauterine Growth Retardation

Animals with intrauterine growth retardation (IUGR) usually undergo injured postnatal growth and development during the early period after birth. Equol (Eq), an isoflavan produced by gut bacteria in response to daidzein intake, has various health benefits. Therefore, the objective of this study was to evaluate whether Eq supplementation can influence the growth performance, redox status, intestinal health and skeletal muscle development of weanling piglets with IUGR. A total of 10 normal-birth-weight (NBW) newborn female piglets and 20 newborn female piglets with IUGR were selected. After weaning at the age of 21 d, 10 NBW piglets and 10 IUGR piglets were allocated to the NBW group and IUGR group, respectively, and offered a basal diet. The other 10 IUGR piglets were allocated to the IUGR + Eq group and offered a basal diet with 50 mg of Eq per kg of diet. The whole trial lasted for 21 d. At the end of the feeding trial, all piglets were sacrificed for the collection of serum, intestinal tissues and skeletal muscles. Supplementation with Eq increased the average daily gain (ADG), average daily feed intake (ADFI), duodenal villus height to crypt depth ratio (V/C), jejunal villus height and V/C, but reduced the duodenal crypt depth in neonatal piglets with IUGR. Meanwhile, Eq supplementation elevated the activities of superoxide dismutase (SOD) and catalase (CAT) in the serum and duodenum and the activity of SOD in the jejunum, but lowered malondialdehyde (MDA) content in the serum, jejunum and ileum of piglets with IUGR. In addition, supplementation with Eq reduced diamine oxidase (DAO) activity and the levels of D-lactate and endotoxin in serum, and the tumor necrosis factor-α (TNF-α) level in jejunum and ileum, whereas the concentration of serum immunoglobulin G (IgG) and the mRNA levels of intestinal barrier-related markers in jejunum and ileum of IUGR piglets were increased. Furthermore, supplementation with Eq elevated the percentage of fast-fibers and was accompanied with higher mRNA expression of myosin heavy chain IIb (MyHC IIb) and lower mRNA levels in MyHC I in the longissimus thoracis (LT) muscle of IUGR piglets. In summary, Eq supplementation can promote antioxidant capacity, maintain intestinal health and facilitate skeletal muscle development, thus resulting in the higher growth performance of IUGR piglets.

Short-Term Soy Bread Intervention Leads to a Dose-Response Increase in Urinary Isoflavone Metabolites and Satiety in Chronic Pancreatitis

Patients with chronic pancreatitis (CP) are particularly vulnerable to nutrient malabsorption and undernutrition caused by the underlying pathology of their disease. Dietary intervention trials involving soy isoflavones in patients with CP are limited and isoflavone metabolites have not yet been reported. We hypothesized soy bread containing plant-based protein, dietary fiber, and isoflavones would be well-tolerated and restore gut functional capacity which would lead to isoflavone metabolites profiles like those of healthy populations. Participants (n = 9) received 1 week of soy bread in a dose-escalation design (1 to 3 slices/day) or a 4-week maximally tolerated dose (n = 1). Dietary adherence, satiety, and palatability were measured. Isoflavone metabolites from 24 h urine collections were quantified using high-performance liquid chromatography. A maximum dose of three slices (99 mg of isoflavones) of soy bread per day was achieved. Short-term exposure to soy bread showed a significant dose-response increase (p = 0.007) of total isoflavones and their metabolites in urine. With increasing slices of soy bread, dietary animal protein intake (p = 0.009) and perceived thirst (p < 0.001) significantly decreased with prolonged satiety (p < 0.001). In this study, adherence to short-term intervention with soy bread in CP patients was excellent. Soy isoflavones were reliably delivered. These findings provide the foundation for evaluating a well-characterized soy bread in supporting healthy nutrition and gut function in CP.

Interplay between Phytochemicals and the Colonic Microbiota

Phytochemicals are natural compounds found in food ingredients with a variety of health-promoting properties. Phytochemicals improve host health through their direct systematic absorption into the circulation and modulation of the gut microbiota. The gut microbiota increases the bioactivity of phytochemicals and is a symbiotic partner whose composition and/or diversity is altered by phytochemicals and affects host health. In this review, the interactions of phytochemicals with the gut microbiota and their impact on human diseases are reviewed. We describe the role of intestinal microbial metabolites, including short-chain fatty acids, amino acid derivatives, and vitamins, from a therapeutic perspective. Next, phytochemical metabolites produced by the gut microbiota and the therapeutic effect of some selected metabolites are reviewed. Many phytochemicals are degraded by enzymes unique to the gut microbiota and act as signaling molecules in antioxidant, anti-inflammatory, anticancer, and metabolic pathways. Phytochemicals can ameliorate diseases by altering the composition and/or diversity of the gut microbiota, and they increase the abundance of some gut microbiota that produce beneficial substances. We also discuss the importance of investigating the interactions between phytochemicals and gut microbiota in controlled human studies.

Dietary Phenolic Compounds: Their Health Benefits and Association with the Gut Microbiota

Oxidative stress causes various diseases, such as type II diabetes and dyslipidemia, while antioxidants in foods may prevent a number of diseases and delay aging by exerting their effects in vivo. Phenolic compounds are phytochemicals such as flavonoids which consist of flavonols, flavones, flavanonols, flavanones, anthocyanidins, isoflavones, lignans, stilbenoids, curcuminoids, phenolic acids, and tannins. They have phenolic hydroxyl groups in their molecular structures. These compounds are present in most plants, are abundant in nature, and contribute to the bitterness and color of various foods. Dietary phenolic compounds, such as quercetin in onions and sesamin in sesame, exhibit antioxidant activity and help prevent cell aging and diseases. In addition, other kinds of compounds, such as tannins, have larger molecular weights, and many unexplained aspects still exist. The antioxidant activities of phenolic compounds may be beneficial for human health. On the other hand, metabolism by intestinal bacteria changes the structures of these compounds with antioxidant properties, and the resulting metabolites exert their effects in vivo. In recent years, it has become possible to analyze the composition of the intestinal microbiota. The augmentation of the intestinal microbiota by the intake of phenolic compounds has been implicated in disease prevention and symptom recovery. Furthermore, the “brain–gut axis”, which is a communication system between the gut microbiome and brain, is attracting increasing attention, and research has revealed that the gut microbiota and dietary phenolic compounds affect brain homeostasis. In this review, we discuss the usefulness of dietary phenolic compounds with antioxidant activities against some diseases, their biotransformation by the gut microbiota, the augmentation of the intestinal microflora, and their effects on the brain–gut axis.

Estrogenic flavonoids and their molecular mechanisms of action

Flavonoids are a major group of phytoestrogens associated with physiological effects, and ecological and social impacts. Although the estrogenic activity of flavonoids was reported by researchers in the fields of medical, environmental and food studies, their molecular mechanisms of action have not been comprehensively reviewed. The estrogenic activity of the respective classes of flavonoids, anthocyanidins/anthocyanins, 2-arylbenzofurans/3-arylcoumarins/α-methyldeoxybenzoins, aurones/chalcones/dihydrochalcones, coumaronochromones, coumestans, flavans/flavan-3-ols/flavan-4-ols, flavanones/dihydroflavonols, flavones/flavonols, homoisoflavonoids, isoflavans, isoflavanones, isoflavenes, isoflavones, neoflavonoids, oligoflavonoids, pterocarpans/pterocarpenes, and rotenone/rotenoids, was summarized through a comprehensive literature search, and their structure-activity relationship, biological activities, signaling pathways, and applications were discussed. Although the respective classes of flavonoids contained at least one chemical mimicking estrogen, the mechanisms varied, such as those with estrogenic, anti-estrogenic, non-estrogenic, and biphasic activities, and additional activities through crosstalk/bypassing, which exert biological activities through cell signaling pathways. Such mechanistic variations of estrogen action are not limited to flavonoids and are observed among other broad categories of chemicals, thus this group of chemicals can be termed as the "estrogenome". This review article focuses on the connection of estrogen action mainly between the outer and the inner environments, which represent variations of chemicals and biological activities/signaling pathways, respectively, and form the basis to understand their applications. The applications of chemicals will markedly progress due to emerging technologies, such as artificial intelligence for precision medicine, which is also true of the study of the estrogenome including estrogenic flavonoids.

Therapeutic Potential of Phenolic Compounds in Medicinal Plants-Natural Health Products for Human Health

Phenolic compounds and flavonoids are potential substitutes for bioactive agents in pharmaceutical and medicinal sections to promote human health and prevent and cure different diseases. The most common flavonoids found in nature are anthocyanins, flavones, flavanones, flavonols, flavanonols, isoflavones, and other sub-classes. The impacts of plant flavonoids and other phenolics on human health promoting and diseases curing and preventing are antioxidant effects, antibacterial impacts, cardioprotective effects, anticancer impacts, immune system promoting, anti-inflammatory effects, and skin protective effects from UV radiation. This work aims to provide an overview of phenolic compounds and flavonoids as potential and important sources of pharmaceutical and medical application according to recently published studies, as well as some interesting directions for future research. The keyword searches for flavonoids, phenolics, isoflavones, tannins, coumarins, lignans, quinones, xanthones, curcuminoids, stilbenes, cucurmin, phenylethanoids, and secoiridoids medicinal plant were performed by using Web of Science, Scopus, Google scholar, and PubMed. Phenolic acids contain a carboxylic acid group in addition to the basic phenolic structure and are mainly divided into hydroxybenzoic and hydroxycinnamic acids. Hydroxybenzoic acids are based on a C6-C1 skeleton and are often found bound to small organic acids, glycosyl moieties, or cell structural components. Common hydroxybenzoic acids include gallic, syringic, protocatechuic, p-hydroxybenzoic, vanillic, gentistic, and salicylic acids. Hydroxycinnamic acids are based on a C6-C3 skeleton and are also often bound to other molecules such as quinic acid and glucose. The main hydroxycinnamic acids are caffeic, p-coumaric, ferulic, and sinapic acids.

Flavonoid intake is associated with lower all-cause and disease-specific mortality: The National Health and Nutrition Examination Survey 2007-2010 and 2017-2018

Adequate intake of flavonoids may influence mortality, particularly of heart and cerebrovascular diseases. However, the importance of each flavonoid and its subclasses in preventing all-cause and disease-specific mortalities remain unclear. In addition, it is unknown which population groups would benefit from high flavonoid intake. Therefore, personalized mortality risk based on flavonoid intake needs to be estimated. The association between flavonoid intake and mortality among 14,029 participants in the National Health and Nutrition Examination Survey was examined using Cox proportional hazards analysis. A prognostic risk score and nomogram linking flavonoid intake and mortality were constructed. During a median follow-up of 117 months (9.75 years), 1,603 incident deaths were confirmed. Total flavonol intake was associated with a significantly reduced all-cause mortality [multivariable adjusted hazard ratio [HR] (95% confidence interval [CI]), 0.87 (0.81, 0.94), p for trend <0.001], especially in participants aged 50 years and older and former smokers. Similarly, total anthocyanidin intake was inversely associated with all-cause mortality [0.91 (0.84, 0.99), p for trend = 0.03], which was most significant in non-alcoholics. The intake of isoflavones was negatively associated with all-cause mortality [0.81 (0.70, 0.94), p = 0.01]. Moreover, a risk score was constructed based on survival-related flavonoid intake. The constructed nomogram accurately predicted the all-cause mortality of individuals based on flavonoid intake. Taken together, our results can be used to improve personalized nutrition.

Effects of inulin on calcium metabolism and bone health

Inulin, a dietary fibre found in the roots of many plants, has positive effects on health. It is particularly noteworthy due to its positive impact on calcium metabolism. Inulin has significant functions, such as improving calcium absorption through passive diffusion, bolstering calcium absorption via ion exchange and expanding the absorption surface of the colon by stimulating cell growth. In addition, inulin boosts calcium absorption by increasing calcium solubility, stimulating levels of calcium-binding protein expression and increasing useful microorganisms. It increases calbindin levels and stimulates transcellular active calcium transport. An inulin intake of least 8-10 g/day supports calcium absorption and total body bone mineral content/density in adolescents through its known mechanisms of action. It also significantly enhances calcium absorption and improves bone health in postmenopausal women and adult men. Sustained and sufficient inulin supplementation in adults has a positive effect on calcium metabolism and bone mineral density.

Effect of Bifidobacterium on osteoclasts: TNF-α/NF-κB inflammatory signal pathway-mediated mechanism

Osteoporosis is a systemic multifactorial bone disease characterized by low bone quality and density and bone microstructure damage, increasing bone fragility and fracture vulnerability. Increased osteoclast differentiation and activity are important factors contributing to bone loss, which is a common pathological manifestation of bone diseases such as osteoporosis. TNF-a/NF-κB is an inflammatory signaling pathway with a key regulatory role in regulating osteoclast formation, and the classical pathway RANKL/RANK/OPG assists osteoclast formation. Activation of this inflammatory pathway promotes the formation of osteoclasts and accelerates the process of osteoporosis. Recent studies and emerging evidence have consistently demonstrated the potential of probiotics to modulate bone health. Secretions of Bifidobacterium, a genus of probiotic bacteria in the phylum Actinobacteria, such as short-chain fatty acids, equol, and exopolysaccharides, have indicated beneficial effects on bone health. This review discusses the molecular mechanisms of the TNF-a/NF-κB inflammatory pathway in regulating osteoclast formation and describes the secretions produced by Bifidobacterium and their potential effects on bone health through this pathway, opening up new directions for future research.

Characterization of fecal microbiota in cervical cancer patients associated with tumor stage and prognosis

Cervical cancer (CC) is the fourth most frequent malignancy among women worldwide, and its prevention and treatment are evolving rapidly. The gut microbiota has been reported to play a crucial role both in the preservation of homeostasis and the development of cervical cancer. In this study, we collected fecal samples to investigate the microbial signatures in cervical cancer patients compared with healthy controls using 16S rRNA sequencing analysis and metagenomic next-generation sequencing (mNGS) testing. Our findings demonstrated a substantial difference in the gut microbiota composition of cervical cancer patients and healthy controls. The disease and stage were most significantly negatively correlated with Ruminococcus 2, which might be considered a potential clinically relevant biomarker. Functions of differential microbiomes were also analyzed, indicating significant differences in metabolisms and biosynthesis between the two groups. These findings demonstrate that patients with cervical cancer have certain species of gut microbiota that are exclusive to them and particular species have the potential to be used in the prognosis of cervical cancer.

Gut microbiota and acylcarnitine metabolites connect the beneficial association between equol and adiposity in adults: a prospective cohort study

BACKGROUND

Many studies have investigated the effects of soy isoflavones on weight control, but few have focused on the role of equol, a gut-derived metabolite of daidzein with greater bioavailability than other soy isoflavones.

OBJECTIVES

This study examined the association of equol production with obesity and explored the mediating roles of equol-related gut microbiota and microbial carnitine metabolites.

METHODS

This 6.6-y prospective study included 2958 Chinese adults (2011 females and 947 males) aged 60.6 ± 6.0 y (mean ± SD) at baseline. Urinary equol and isoflavones were measured using HPLC-tandem MS. BMI, percentage fat mass (%FM), and serum triglycerides (TGs) were assessed every 3 y. Metagenomics sequencing and assessment of carnitine metabolites in feces were performed in a subsample of 897 participants.

RESULTS

Urinary equol, but not daidzein and genistein, was independently and inversely associated with the obesity-related indicators of BMI, %FM, and a biomarker (TGs). Equol producers (EPs) had lower odds of adiposity conditions and a reduced risk of 6.6-y obesity progression than non-EPs among total participants. Gut microbial analyses indicated that EPs had higher microbiome species richness (P = 3.42 × 10-5) and significantly different β-diversity of gut microbiota compared with the non-EP group (P = 0.001), with 20 of 162 species differing significantly. EPs (compared with non-EPs) had higher abundances of Alistipes senegalensis and Coprococcus catus but lower abundances of Ruminococcus gnavus (false discovery rate <0.05). Among the 7 determined fecal acylcarnitine metabolites, palmitoylcarnitine, oleylcarnitine 18:1, and stearylcarnitine were inversely associated with EPs but positively correlated with obesity conditions and progression. Path analyses indicated that the beneficial association between equol and obesity might be mediated by gut microbiota and decreased production of 3 acylcarnitines in feces.

CONCLUSIONS

This study suggests a beneficial association between equol and obesity, mediated by the gut microbiome and acylcarnitines, in adults.This trial was registered at clinicaltrials.gov as NCT03179657.

High Titer of (S)-Equol Synthesis from Daidzein in Escherichia coli

(S)-Equol is the terminal metabolite of daidzein and plays important roles in human health. However, due to anaerobic inefficiency, limited productivity in (S)-equol-producing strains often hinders (S)-equol mass production. Here, a multi-enzyme cascade system was designed to generate a higher (S)-equol titer. First, full reversibility of the (S)-equol synthesis pathway was found and a blocking reverse conversion strategy was established. As biosynthetic genes are present in the microbial genome, an effective daidzein reductase was chosen using evolutionary principles. And our analyses showed that NADPH was crucial for the pathway. In response to this, a novel NADPH pool was redesigned after analyzing a cofactor metabolism model. By adjusting synthesis pathway genes at the right expression level, the entire synthesis pathway can take place smoothly. Thus, the cascade system was optimized by regulating the gene expression intensity. Finally, after optimizing fermentation conditions, a 5 L bioreactor was used to generate a high (S)-equol production titer (3418.5 mg/L), with a conversion rate of approximately 85.9%. This study shows a feasible green process route for the production of (S)-equol.

Soy isoflavone-specific biotransformation product S-equol in the colon: physiological functions, transformation mechanisms, and metabolic regulatory pathways

Epidemiological data suggest that regular intake of soy isoflavones may reduce the incidence of estrogen-dependent and aging-associated disorders. Equol is a metabolite of soy isoflavone (SI) produced by specific gut microbiota and has many beneficial effects on human health due to its higher biological activity compared to SI. However, only 1/3 to 1/2 of humans are able to produce equol in the body, which means that not many people can fully benefit from SI. This review summarizes the recent advances in equol research, focusing on the chemical properties, physiological functions, conversion mechanisms in vitro and vivo, and metabolic regulatory pathways affecting S-equol production. Advanced experimental designs and possible techniques in future research plan are also fully discussed. Furthermore, this review provides a fundamental basis for researchers in the field to understand individual differences in S-equol production, the efficiency of metabolic conversion of S-equol, and fermentation production of S-equol in vitro.

Modulatory Effect of Gut Microbiota on the Gut-Brain, Gut-Bone Axes, and the Impact of Cannabinoids

The gut microbiome is a collection of microorganisms and parasites in the gastrointestinal tract. Many factors can affect this community's composition, such as age, sex, diet, medications, and environmental triggers. The relationship between the human host and the gut microbiota is crucial for the organism's survival and development, whereas the disruption of this relationship can lead to various inflammatory diseases. Cannabidiol (CBD) and tetrahydrocannabinol (THC) are used to treat muscle spasticity associated with multiple sclerosis. It is now clear that these compounds also benefit patients with neuroinflammation. CBD and THC are used in the treatment of inflammation. The gut is a significant source of nutrients, including vitamins B and K, which are gut microbiota products. While these vitamins play a crucial role in brain and bone development and function, the influence of gut microbiota on the gut-brain and gut-bone axes extends further and continues to receive increasing scientific scrutiny. The gut microbiota has been demonstrated to be vital for optimal brain functions and stress suppression. Additionally, several studies have revealed the role of gut microbiota in developing and maintaining skeletal integrity and bone mineral density. It can also influence the development and maintenance of bone matrix. The presence of the gut microbiota can influence the actions of specific T regulatory cells, which can lead to the development of bone formation and proliferation. In addition, its metabolites can prevent bone loss. The gut microbiota can help maintain the bone's equilibrium and prevent the development of metabolic diseases, such as osteoporosis. In this review, the dual functions gut microbiota plays in regulating the gut-bone axis and gut-brain axis and the impact of CBD on these roles are discussed.

Can soy isoflavones in combination with soy protein change serum concentration of adiponectin and resistin? A systematic review and meta-analysis on randomized clinical trials

Some studies proposed the anti-inflammatory effect of soy protein and soy isoflavones by changing the serum adiponectin and resistin levels. The purpose of this research was to determine the impact of soy isoflavones and soy protein on blood adiponectin and resistin levels in adults. Scopus, PubMed, Cochrane Library, ISI Web of Science, and ClinicalTrials.gov databases were searched until April 2022. The effect size was computed by the mean changes from the beginning for intervention and comparison groups and their standard deviation. In the case of significant heterogeneity, DerSimonian and Laird random-effects model was used. Six and five clinical trials were selected for the systematic review and meta-analysis, respectively. The overall estimate indicated that soy isoflavones in combination with soy protein did not significantly change serum adiponectin level (weighted mean differences (WMD) = 0.36 μg/ml; 95% confidence interval (CI): -0.26, 0.99; p = .25), but significantly increased serum resistin level (WMD = 0.64 ng/ml, 95% CI: 0.25, 1.04; p = .001). In combination with soy protein, soy isoflavones nonsignificantly increased serum adiponectin levels, but significantly increased resistin levels. New intervention studies with a high dose of soy isoflavones and soy protein in different parts of the world and an updated meta-analysis are needed to confirm the results of our study.

In Silico Molecular Docking and ADMET Analysis for Drug Development of Phytoestrogens Compound with Its Evaluation of Neurodegenerative Diseases

Neurodegenerative disease is one of the problems faced by postmenopausal women due to estrogen deficiency. Phytoestrogen compounds can be used as an alternative treatment for diseases caused by estrogen deficiency by binding to their receptors through the estrogen receptor (ER) dependent pathway. With in silico studies, this study aims to predict how phytoestrogen compounds will stop neurons from dying by using the dependent ER pathway. Genistein, daidzein, glycitein, formononetin, biochanin A, equol, pinoresinol, 4-methoxypinoresinol, eudesmin, α-amyrin, and β-amyrin compounds were prepared with ChemDraw Ultra 12.0. Then their pharmacokinetic and pharmacodynamic properties were examined using SwissADME. Geometry optimization of the compound was performed using Avogadro 1.0.1, and molecular docking of the compound to the ERα (1A52) and ERβ (5TOA) receptors was performed using AutoDock vina (PyRx 0.8). The interaction visualization stage was carried out with Biovia Discover Studio 2021, while the toxicity values of the compounds were analyzed using pkCSM and ProTox II. The results showed that the equol compound met the pharmacokinetic, pharmacodynamic, toxicity criteria, and had similarities with the native ligand 17β-estradiol. Equol compound inhibits neurodegeneration via an ER-dependent pathway by binding to ERα (1A52) and ERβ (5TOA) receptors.

Gut Microbiota-Assisted Synthesis, Cellular Interactions and Synergistic Perspectives of Equol as a Potent Anticancer Isoflavone

It is well known that, historically, plants have been an important resource of anticancer agents, providing several clinically approved drugs. Numerous preclinical studies have shown a strong anticancer potential of structurally different phytochemicals, including polyphenolic constituents of plants, flavonoids. In this review article, suppressing effects of equol in different carcinogenesis models are unraveled, highlighting the mechanisms involved in these anticancer activities. Among flavonoids, daidzein is a well-known isoflavone occurring in soybeans and soy products. In a certain part of population, this soy isoflavone is decomposed to equol under the action of gut microflora. Somewhat surprisingly, this degradation product has been shown to be more bioactive than its precursor daidzein, revealing a strong and multifaceted anticancer potential. In this way, it is important to bear in mind that the metabolic conversion of plant flavonoids might lead to products that are even more efficient than the parent compounds themselves, definitely deserving further studies.

Dietary Isoflavone Aglycons from Soy Germ Pasta Improves Reproductive Performance of Aging Hens and Lowers Cholesterol Levels of Egg Yolk

This study compared dietary isoflavone aglycones with the glycoside conjugates in a novel model of postmenopausal status, the aging domestic hen (Gallus gallus domesticus), to determine the effects on reproductive performance, cholesterol levels, and nutritional quality of eggs laid. Hens, 18 mo old, were randomized into four groups (n = 10/group) and fed for 28 d a conventional poultry corn/soymeal diet (Control), or diets supplemented with isoflavone glycosides from soy germ (diet A), isoflavone aglycons from a soy germ pasta (diet B), or conventional pasta lacking isoflavones (diet C). The egg-laying rate was recorded daily, plasma isoflavones and cholesterol were measured, and the nutritional composition of the eggs was determined. Egg-laying declined over a 4-week period in hens in the Control group and those fed isoflavone glycosides (diets A and C), whereas hens fed isoflavone aglycons (diet B) significantly increased their egg-laying efficiency. The total egg count and egg yield were significantly higher in hens fed isoflavone aglycons, and their plasma cholesterol concentrations were lower and the eggs laid had a 30% lower yolk cholesterol content. None of these effects were observed with diets containing similar levels of isoflavone glycosides. These studies recapitulate the clinical effects of soy germ pasta enriched with isoflavone aglycons and lend support to the greater efficacy of a diet rich in isoflavone aglycons.

Metabolomics profiles of premenopausal women are different based on O-desmethylangolensin metabotype

Urinary O-desmethylangolensin (ODMA) concentrations provide a functional gut microbiome marker of dietary isoflavone daidzein metabolism to ODMA. Individuals who do not have gut microbial environments that produce ODMA have less favourable cardiometabolic and cancer risk profiles. Urinary metabolomics profiles were evaluated in relation to ODMA metabotypes within and between individuals over time. Secondary analysis of data was conducted from the BEAN2 trial, which was a cross-over study of premenopausal women consuming 6 months on a high and a low soya diet, each separated by a 1-month washout period. In all of the 672 samples in the study, sixty-six of the eighty-four women had the same ODMA metabotype at seven or all eight time points. Two or four urine samples per woman were selected based on temporal metabotypes in order to compare within and across individuals. Metabolomics assays for primary metabolism and biogenic amines were conducted in sixty urine samples from twenty women. Partial least-squares discriminant analysis was used to compare metabolomics profiles. For the same ODMA metabotype across different time points, no profile differences were detected. For changes in metabotype within individuals and across individuals with different metabotypes, distinct metabolomes emerged. Influential metabolites (variables importance in projection score > 2) included several phenolic compounds, carnitine and derivatives, fatty acid and amino acid metabolites and some medications. Based on the distinct metabolomes of producers v. non-producers, the ODMA metabotype may be a marker of gut microbiome functionality broadly involved in nutrient and bioactive metabolism and should be evaluated for relevance to precision nutrition initiatives.

The Prevalence of Dietary Supplements That Claim Estrogen-like Effects in Japanese Women

Recently, adverse events, such as irregular vaginal bleeding and menstrual disorders, associated with the use of dietary supplements containing Pueraria mirifica, have been reported in Japan. P. mirifica contains phytoestrogens, such as deoxymiroestrol and miroestrol. Therefore, we investigated the use of supplements that claim to have estrogen-like effects (i.e., estrogen-like supplements) in Japanese women aged from 15 to 69 years old in an online survey. The prevalence of estrogen-like supplement use was 5%, accounting for approximately 15% of the sample, including ex-users. The majority of the users were in their 40s and 50s, mainly using these supplements for the treatment of menopausal symptoms. In contrast, the younger generation mainly used them for beauty purposes, such as weight loss, mastogenic effects, and skin care. Many of them visited a clinic or took medicines for menstrual-related troubles. In all age groups, soybeans/isoflavones were the most commonly used, followed by equol and placenta. Participants in their teens and 20s also used P. mirifica. Among them, 16.2% had experienced adverse events, including irregular vaginal bleeding, breast swelling and pain, and heavy menstruation. In conclusion, estrogen-like supplement use is associated with adverse events; thus, it is necessary to pay attention to the use of these supplement. Furthermore, because the purpose of use differs depending on generation, caution according to each generation is necessary.

Potential Protective Mechanisms of S-equol, a Metabolite of Soy Isoflavone by the Gut Microbiome, on Cognitive Decline and Dementia

S-equol, a metabolite of soy isoflavone daidzein transformed by the gut microbiome, is the most biologically potent among all soy isoflavones and their metabolites. Soy isoflavones are phytoestrogens and exert their actions through estrogen receptor-β. Epidemiological studies in East Asia, where soy isoflavones are regularly consumed, show that dietary isoflavone intake is inversely associated with cognitive decline and dementia; however, randomized controlled trials of soy isoflavones in Western countries did not generally show their cognitive benefit. The discrepant results may be attributed to S-equol production capability; after consuming soy isoflavones, 40-70% of East Asians produce S-equol, whereas 20-30% of Westerners do. Recent observational and clinical studies in Japan show that S-equol but not soy isoflavones is inversely associated with multiple vascular pathologies, contributing to cognitive impairment and dementia, including arterial stiffness and white matter lesion volume. S-equol has better permeability to the blood-brain barrier than soy isoflavones, although their affinity to estrogen receptor-β is similar. S-equol is also the most potent antioxidant among all known soy isoflavones. Although S-equol is available as a dietary supplement, no long-term trials in humans have examined the effect of S-equol supplementation on arterial stiffness, cerebrovascular disease, cognitive decline, or dementia.

The health effects of soy: A reference guide for health professionals

Soy is a hotly debated and widely discussed topic in the field of nutrition. However, health practitioners may be ill-equipped to counsel clients and patients about the use of soyfoods because of the enormous, and often contradictory, amount of research that has been published over the past 30 years. As interest in plant-based diets increases, there will be increased pressure for practitioners to gain a working knowledge of this area. The purpose of this review is to provide concise literature summaries (400-500 words) along with a short perspective on the current state of knowledge of a wide range of topics related to soy, from the cholesterol-lowering effects of soy protein to the impact of isoflavones on breast cancer risk. In addition to the literature summaries, general background information on soyfoods, soy protein, and isoflavones is provided. This analysis can serve as a tool for health professionals to be used when discussing soyfoods with their clients and patients.

Biocatalytic synthesis and evaluation of antioxidant and antibacterial activities of hydroxyequols

Hydroxyequols are promising analogues of the biologically active flavonoid, equol. We recently found that the flavin-dependent monooxygenase HpaB_ro-3 of Rhodococcus opacus regioselectively synthesizes 3'-hydroxyequol from equol, whereas HpaB_pl-1 of Photorhabdus luminescens synthesizes 6-hydroxyequol. In this study, we investigated the cascade synthesis of a dihydroxyequol compound from equol using these two enzymes. When Escherichia coli cells expressing HpaB_ro-3 and cells expressing HpaB_pl-1 were simultaneously incubated with equol, the cells efficiently synthesized 6,3'-dihydroxyequol (8.7 mM, 2.4 g/L) via 3'- and 6-hydroxyequols in one pot. The antioxidant activity of the equol derivatives increased with an increase in the number of hydroxyl groups on the equol scaffold. 6,3'-Dihydroxyequol exhibited potent antioxidant activity. In addition, 6-hydroxyequol significantly inhibited the growth of E. coli. Cell survival studies suggested that 6-hydroxyequol is a bactericidal rather than bacteriostatic compound. To our knowledge, this is the first report describing the antibacterial activity of hydroxyequols.

Esterases From Bifidobacteria Exhibit the Conversion of Albiflorin in Gut Microbiota

Bifidobacteria is an important microbe that inhabits the human gut. It is capable of metabolizing complex compounds in the human diet. Albiflorin, an antidepressant natural product from Radix Paeoniae Alba in China, is difficult to absorb after oral administration, and its metabolism has been proven to be closely related to the gut microbiota. In this study, we demonstrated in vitro that several Bifidobacteria species were able to convert albiflorin to benzoic acid, and four esterases (B2, B3, B4, and BL) from Bifidobacterium breve and Bifidobacterium longum were found through genome mining and modeled by SWISS-MODEL. B2 and B3 presented the strongest albiflorin metabolism ability. The optimal conditions, including temperature, buffer, and pH, for the conversion of albiflorin by the four esterases were investigated. Furthermore, the effect of esterase on the metabolism of albiflorin in vivo was confirmed by transplanting bacteria containing esterase B2. This study demonstrated the vital role of esterases from Bifidobacteria in the metabolism of natural compounds containing ester bonds, which could contribute to the development of new enzymes, microbial evolution, and probiotic adjuvant compounds for treatment.

Microwave Microfluidic Sensor for Detection of High Equol Concentrations in Aqueous Solution

This paper presents a Peano fractal geometry complementary split ring resonator (PFCSRR) loaded microstrip transmission line with a microfluidic channel for equol (EQ) sensing in a high and wide range of concentrations in aqueous solution. The proposed sensor was designed based on a CSRR loaded microstrip line with a Peano fractal in the center of a CSRR and validated through simulation and experiment. The microfluidic channel was fabricated using polydimethylsiloxane (PDMS) and installed to cover the sensing area. The free space, empty microfluidic channels, deionized (DI) water, dimethyl sulfoxide (DMSO), and various concentrations of EQ were measured by a microwave sensor through sample-filled microfluidic channels. Detection of high levels of EQ was in the concentration range of 0.01 mM - 100 mM. The materials under test (MUTs) were measured in the frequency range of 1.0 GHz-3.5 GHz based on the magnitude of the transmission coefficient (S₂₁) and resonance frequency (F_r) at room temperature. The S₂₁ and F_r were recorded and analyzed by logarithmic concentrations of EQ for the determinant of the correlations between EQ concentration and S₂₁ and F_r. Principal component analysis (PCA) and K-means clustering were used to analyze and classify groups of MUTs.

Putative Mechanisms Underlying the Beneficial Effects of Polyphenols in Murine Models of Metabolic Disorders in Relation to Gut Microbiota

The beneficial effects of polyphenols on metabolic disorders have been extensively reported. The interaction of these compounds with the gut microbiota has been the focus of recent studies. In this review, we explored the fundamental mechanisms underlying the beneficial effects of polyphenols in relation to the gut microbiota in murine models of metabolic disorders. We analyzed the effects of polyphenols on three murine models of metabolic disorders, namely, models of a high-fat diet (HFD)-induced metabolic disorder, dextran sulfate sodium (DSS)-induced colitis, and a metabolic disorder not associated with HFD or DSS. Regardless of the model, polyphenols ameliorated the effects of metabolic disorders by alleviating intestinal oxidative stress, improving inflammatory status, and improving intestinal barrier function, as well as by modulating gut microbiota, for example, by increasing the abundance of short-chain fatty acid-producing bacteria. Consequently, polyphenols reduce circulating lipopolysaccharide levels, thereby improving inflammatory status and alleviating oxidative imbalance at the lesion sites. In conclusion, polyphenols likely act by regulating intestinal functions, including the gut microbiota, and may be a safe and suitable therapeutic agent for various metabolic disorders.