Shared mechanisms among probiotic taxa: implications for general probiotic claims

Strain-specificity of probiotic effects has been a cornerstone principle of probiotic science for decades. Certainly, some important mechanisms are present in only a few probiotic strains. But scientific advances now reveal commonalities among members of certain taxonomic groups of probiotic microbes. Some clinical benefits likely derive from these shared mechanisms, suggesting that sub-species-specific, speciesspecific or genus-specific probiotic effects exist. Human trials are necessary to confirm specific health benefits. However, a strain that has not been tested in human efficacy trials may meet the minimum definition of the term ‘probiotic’ if it is a member of a well-studied probiotic species expressing underlying core mechanisms and it is delivered at an effective dose

Author Correction: Probiotics and prebiotics in intestinal health and disease: from biology to the clinic (Nature Reviews Gastroenterology & Hepatology, (2019), 16, 10, (605-616), 10.1038/s41575-019-0173-3)

© 2019, Springer Nature Limited. In the original article published online, the Competing Interests statement was incorrect and should have stated the following: M.E.S. declares personal fees related to probiotics from the following entities: California Dairy Research Foundation, Clorox, Danone, Danone USA, Dutch Mill, General Mills, JHeimbach, Kelley Drye & Warren, Kellogg, Kerry, Medscape, Nestle, New Chapter, Pepsico, Pfizer, Pharmavite, Probi, Procter & Gamble, Trouw Nutrition, Visalia Dairy Company, Williams Mullen, Winclove Probiotics and Yakult. D.J.M. declares personal fees for consulting for Bayer and Pharmavite. G.R. declares that he helped develop and commercialize probiotic strains GR-1 and RC-14, but has had no financial interest in them for over 10 years. He is Chief Scientific Officer for Seed, a company producing probiotic products. Over the past 3 years, he has consulted on probiotics with Acerus Pharmaceuticals, Altmann, Chr. Hansen, Danone, KGK Science, Kimberly-Clark, Metagenics and Seed. G.R.G. and R.A.R. declare no competing interests. This error has been corrected in the HTML and PDF versions of the article

Probiotics and prebiotics in intestinal health and disease: from biology to the clinic

Probiotics and prebiotics are microbiota-management tools for improving host health. They target gastrointestinal effects via the gut, although direct application to other sites such as the oral cavity, vaginal tract and skin is being explored. Here, we describe gut-derived effects in humans. In the past decade, research on the gut microbiome has rapidly accumulated and has been accompanied by increased interest in probiotics and prebiotics as a means to modulate the gut microbiota. Given the importance of these approaches for public health, it is timely to reiterate factual and supporting information on their clinical application and use. In this Review, we discuss scientific evidence on probiotics and prebiotics, including mechanistic insights into health effects. Strains of Lactobacillus, Bifidobacterium and Saccharomyces have a long history of safe and effective use as probiotics, but Roseburia spp., Akkermansia spp., Propionibacterium spp. and Faecalibacterium spp. show promise for the future. For prebiotics, glucans and fructans are well proven, and evidence is building on the prebiotic effects of other substances (for example, oligomers of mannose, glucose, xylose, pectin, starches, human milk and polyphenols)

Shared mechanisms among probiotic taxa: implications for general probiotic claims

Strain-specificity of probiotic effects has been a cornerstone principle of probiotic science for decades. Certainly, some important mechanisms are present in only a few probiotic strains. But scientific advances now reveal commonalities among members of certain taxonomic groups of probiotic microbes. Some clinical benefits likely derive from these shared mechanisms, suggesting that sub-species-specific, species specific or genus-specific probiotic effects exist. Human trials are necessary to confirm specific health benefits. However, a strain that has not been tested in human efficacy trials may meet the minimum definition of the term ‘probiotic’ if it is a member of a well-studied probiotic species expressing underlying core mechanisms and it is delivered at an effective dose

A Classification System for Defining and Estimating Dietary Intake of Live Microbes in US Adults and Children

Background: Consuming livemicrobes in foods may benefit human health. Live microbe estimates have not previously been associated with individual foods in dietary databases. Objectives: We aimed to estimate intake of live microbes in US children (aged 2–18 y) and adults (≥19 y) (n = 74,466; 51.2% female). Methods: Using cross-sectional data from the NHANES (2001–2018), experts assigned foods an estimated level of live microbes per gram [low (Lo), \u3c104 CFU/g; medium (Med), 104–107 CFU/g; or high (Hi), \u3e107 CFU/g]. Probiotic dietary supplements were also assessed. The mean intake of each live microbe category and the percentages of subjects who ate from each live microbe category were determined. Nutrients from foods with live microbes were also determined using the population ratio method. Because the Hi category comprised primarily fermented dairy foods, we also looked at aggregated data for Med or Hi (MedHi), which included an expanded range of live microbe–containing foods, including fruits and vegetables. Results: Our analysis showed that 52%, 20%, and 59% of children/adolescents, and 61%, 26%, and 67% of adults, consumed Med, Hi, or MedHi foods, respectively. Per capita intake of Med, Hi, and MedHi foods was 69, 16, and 85 g/d for children/adolescents, and 106, 21, and 127 g/d for adults, respectively. The proportion of subjects who consumed live microbes and overall per capita intake increased significantly over the 9 cycles/18-y study period (0.9–3.1 g/d per cycle in children across categories and 1.4 g/d per cycle in adults for the Med category). Conclusions: This study indicated that children, adolescents, and adults in the United States steadily increased their consumption of foods with live microbes between the earliest (2001–2002) and latest (2017–2018) survey cycles. Additional research is needed to determine the relations between exposure to live microbes in foods and specific health outcomes or biomarkers

Clinical Reactivations of Herpes Simplex Virus Type 2 Infection and Human Immunodeficiency Virus Disease Progression Markers

BACKGROUND: The natural history of HSV-2 infection and role of HSV-2 reactivations in HIV disease progression are unclear. METHODS: Clinical symptoms of active HSV-2 infection were used to classify 1,938 HIV/HSV-2 co-infected participants of the Women's Interagency HIV Study (WIHS) into groups of varying degree of HSV-2 clinical activity. Differences in plasma HIV RNA and CD4+ T cell counts between groups were explored longitudinally across three study visits and cross-sectionally at the last study visit. RESULTS: A dose dependent association between markers of HIV disease progression and degree of HSV-2 clinical activity was observed. In multivariate analyses after adjusting for baseline CD4+ T cell levels, active HSV-2 infection with frequent symptomatic reactivations was associated with 21% to 32% increase in the probability of detectable plasma HIV RNA (trend p = 0.004), an average of 0.27 to 0.29 log10 copies/ml higher plasma HIV RNA on a continuous scale (trend p<0.001) and 51 to 101 reduced CD4+ T cells/mm(3) over time compared to asymptomatic HSV-2 infection (trend p<0.001). CONCLUSIONS: HIV induced CD4+ T cell loss was associated with frequent symptomatic HSV-2 reactivations. However, effect of HSV-2 reactivations on HIV disease progression markers in this population was modest and appears to be dependent on the frequency and severity of reactivations. Further studies will be necessary to determine whether HSV-2 reactivations contribute to acceleration of HIV disease progression

Associations Between Food Insecurity and Psychotropic Medication Use Among Women Living With HIV in the United States

AIMS: Psychotropic prescription rates continue to increase in the United States (USA). Few studies have investigated whether social-structural factors may play a role in psychotropic medication use independent of mental illness. Food insecurity is prevalent among people living with HIV in the USA and has been associated with poor mental health. We investigated whether food insecurity was associated with psychotropic medication use independent of the symptoms of depression and anxiety among women living with HIV in the USA. METHODS: We used cross-sectional data from the Women\u27s Interagency HIV Study (WIHS), a nationwide cohort study. Food security (FS) was the primary explanatory variable, measured using the Household Food Security Survey Module. First, we used multivariable linear regressions to test whether FS was associated with symptoms of depression (Center for Epidemiologic Studies Depression [CESD] score), generalised anxiety disorder (GAD-7 score) and mental health-related quality of life (MOS-HIV Mental Health Summary score; MHS). Next, we examined associations of FS with the use of any psychotropic medications, including antidepressants, sedatives and antipsychotics, using multivariable logistic regressions adjusting for age, race/ethnicity, income, education and alcohol and substance use. In separate models, we additionally adjusted for symptoms of depression (CESD score) and anxiety (GAD-7 score). RESULTS: Of the 905 women in the sample, two-thirds were African-American. Lower FS (i.e. worse food insecurity) was associated with greater symptoms of depression and anxiety in a dose-response relationship. For the psychotropic medication outcomes, marginal and low FS were associated with 2.06 (p \u3c 0.001; 95% confidence interval [CI] = 1.36-3.13) and 1.99 (p \u3c 0.01; 95% CI = 1.26-3.15) times higher odds of any psychotropic medication use, respectively, before adjusting for depression and anxiety. The association of very low FS with any psychotropic medication use was not statistically significant. A similar pattern was found for antidepressant and sedative use. After additionally adjusting for CESD and GAD-7 scores, marginal FS remained associated with 1.93 (p \u3c 0.05; 95% CI = 1.16-3.19) times higher odds of any psychotropic medication use. Very low FS, conversely, was significantly associated with lower odds of antidepressant use (adjusted odds ratio = 0.42; p \u3c 0.05; 95% CI = 0.19-0.96). CONCLUSIONS: Marginal FS was associated with higher odds of using psychotropic medications independent of depression and anxiety, while very low FS was associated with lower odds. These complex findings may indicate that people experiencing very low FS face barriers to accessing mental health services, while those experiencing marginal FS who do access services are more likely to be prescribed psychotropic medications for distress arising from social and structural factors

Genital herpes evaluation by quantitative TaqMan PCR: correlating single detection and quantity of HSV-2 DNA in cervicovaginal lavage fluids with cross-sectional and longitudinal clinical data

Abstract Objective To evaluate the utility of a single quantitative PCR (qPCR) measurement of HSV (HSV-1&amp;2) DNA in cervicovaginal lavage (CVL) specimens collected from women with predominantly chronic HSV-2 infection in assessing genital HSV shedding and the clinical course of genital herpes (GH) within a cohort with semiannual schedule of follow up and collection of specimens. Methods Two previously described methods used for detection of HSV DNA in mucocutaneous swab samples were adapted for quantification of HSV DNA in CVLs. Single CVL specimens from 509 women were tested. Presence and quantity of CVL HSV DNA were explored in relation to observed cross-sectional and longitudinal clinical data. Results The PCR assay was sensitive and reproducible with a limit of quantification of ~50 copies per milliliter of CVL. Overall, 7% of the samples were positive for HSV-2 DNA with median log10 HSV-2 DNA copy number of 3.9 (IQR: 2.6-5.7). No HSV-1 was detected. Presence and quantity of HSV-2 DNA in CVL directly correlated with the clinical signs and symptoms of presence of active symptomatic disease with frequent recurrences. Conclusion Single qPCR measurement of HSV DNA in CVL fluids of women with chronic HSV-2 infection provided useful information for assessing GH in the setting of infrequent sampling of specimens. Observed positive correlation of the presence and quantity of HSV-2 DNA with the presence of active and more severe course of HSV-2 infection may have clinical significance in the evaluation and management of HSV-2 infected patients

Shared mechanisms among probiotic taxa: implications for general probiotic claims

Strain-specificity of probiotic effects has been a cornerstone principle of probiotic science for decades. Certainly, some important mechanisms are present in only a few probiotic strains. But scientific advances now reveal commonalities among members of certain taxonomic groups of probiotic microbes. Some clinical benefits likely derive from these shared mechanisms, suggesting that sub-species-specific, speciesspecific or genus-specific probiotic effects exist. Human trials are necessary to confirm specific health benefits. However, a strain that has not been tested in human efficacy trials may meet the minimum definition of the term ‘probiotic’ if it is a member of a well-studied probiotic species expressing underlying core mechanisms and it is delivered at an effective dose

Should There Be a Recommended Daily Intake of Microbes?

The collective findings from human microbiome research, randomized controlled trials on specific microbes (i.e., probiotics), and associative studies of fermented dairy consumption provide evidence for the beneficial effects of the regular consumption of safe live microbes. To test the hypothesis that the inclusion of safe, live microbes in the diet supports and improves health, we propose assessment of the types and evidentiary quality of the data available on microbe intake, including the assembly and evaluation of evidence available from dietary databases. Such an analysis would help to identify gaps in the evidence needed to test this hypothesis, which can then be used to formulate and direct initiatives focused on prospective and randomized controlled trials on live microbe consumption. Outcomes will establish whether or not the evidence exists, or can be generated, to support the establishment of dietary recommendations for live microbes