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BackgroundHispanics living in the USA may have unrecognized potential birthplace and lifestyle influences on the gut microbiome. We report a cross-sectional analysis of 1674 participants from four centers of the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), aged 18 to 74 years old at recruitment.ResultsAmplicon sequencing of 16S rRNA gene V4 and fungal ITS1 fragments from self-collected stool samples indicate that the host microbiome is determined by sociodemographic and migration-related variables. Those who relocate from Latin America to the USA at an early age have reductions in Prevotella to Bacteroides ratios that persist across the life course. Shannon index of alpha diversity in fungi and bacteria is low in those who relocate to the USA in early life. In contrast, those who relocate to the USA during adulthood, over 45 years old, have high bacterial and fungal diversity and high Prevotella to Bacteroides ratios, compared to USA-born and childhood arrivals. Low bacterial diversity is associated in turn with obesity. Contrasting with prior studies, our study of the Latino population shows increasing Prevotella to Bacteroides ratio with greater obesity. Taxa within Acidaminococcus, Megasphaera, Ruminococcaceae, Coriobacteriaceae, Clostridiales, Christensenellaceae, YS2 (Cyanobacteria), and Victivallaceae are significantly associated with both obesity and earlier exposure to the USA, while Oscillospira and Anaerotruncus show paradoxical associations with both obesity and late-life introduction to the USA.ConclusionsOur analysis of the gut microbiome of Latinos demonstrates unique features that might be responsible for health disparities affecting Hispanics living in the USA.

Gastrointestinal (GI) mucosal dysfunction predicts and likely contributes to non-infectious comorbidities and mortality in HIV infection and persists despite antiretroviral therapy. However, the mechanisms underlying this dysfunction remain incompletely understood. Neutrophils are important for containment of pathogens but can also contribute to tissue damage due to their release of reactive oxygen species and other potentially harmful effector molecules. Here we used a flow cytometry approach to investigate increased neutrophil lifespan as a mechanism for GI neutrophil accumulation in chronic, treated HIV infection and a potential role for gastrointestinal dysbiosis. We report that increased neutrophil survival contributes to neutrophil accumulation in colorectal biopsy tissue, thus implicating neutrophil lifespan as a new therapeutic target for mucosal inflammation in HIV infection. Additionally, we characterized the intestinal microbiome of colorectal biopsies using 16S rRNA sequencing. We found that a reduced Lactobacillus: Prevotella ratio associated with neutrophil survival, suggesting that intestinal bacteria may contribute to GI neutrophil accumulation in treated HIV infection. Finally, we provide evidence that Lactobacillus species uniquely decrease neutrophil survival and neutrophil frequency in vitro, which could have important therapeutic implications for reducing neutrophil-driven inflammation in HIV and other chronic inflammatory conditions.

BackgroundCannabis is a widely used drug in the United States, and the frequency of cannabis use in the human immunodeficiency virus (HIV)-infected population is disproportionately high. Previous human and macaque studies suggest that cannabis may have an impact on plasma viral load; however, the relationship between cannabis use and HIV-associated systemic inflammation and immune activation has not been well defined.MethodsThe impact of cannabis use on peripheral immune cell frequency, activation, and function was assessed in 198 HIV-infected, antiretroviral-treated individuals by flow cytometry. Individuals were categorized into heavy, medium, or occasional cannabis users or noncannabis users based on the amount of the cannabis metabolite 11-nor-carboxy-tetrahydrocannabinol (THC-COOH) detected in plasma by mass spectrometry.ResultsHeavy cannabis users had decreased frequencies of human leukocyte antigen (HLA)-DR+CD38+CD4+ and CD8+ T-cell frequencies, compared to frequencies of these cells in non-cannabis-using individuals. Heavy cannabis users had decreased frequencies of intermediate and nonclassical monocyte subsets, as well as decreased frequencies of interleukin 23- and tumor necrosis factor-α-producing antigen-presenting cells.ConclusionsWhile the clinical implications are unclear, our findings suggest that cannabis use is associated with a potentially beneficial reduction in systemic inflammation and immune activation in the context of antiretroviral-treated HIV infection.

OBJECTIVE:The aim of the study was to identify associations between improvement in genitourinary symptoms of menopause (GSM) and vaginal microbiota, vaginal glycogen, and serum estrogen. METHODS:Thirty postmenopausal women enrolled in a hot flash treatment trial (oral estradiol vs venlafaxine vs placebo) who reported GSM and provided vaginal swabs at 0, 4, and 8 weeks were studied. Bacterial communities were characterized using deep sequencing targeting the 16S rRNA gene V3-V4 region. Participants selected a most bothersome genitourinary symptom (dryness, discharge, pain, itch/burn, or inability to have sex) and rated severity on a 10-point scale at baseline and 8 weeks. Vaginal glycogen and serum estradiol and estrone were measured at enrollment and 8 weeks. Comparisons according to improvement in most bothersome symptom (MBS) were made using χ, Wilcoxon signed-rank test, or Hotelling's t test. RESULTS:Of 30 participants, 21 (70%) had improvement in MBS over the 8-week study and 9 (30%) had no improvement or worsening of MBS. A higher proportion of women receiving estradiol or venlafaxine reported improvement in MBS (88%, 78%) compared with placebo (54%; P = 0.28). MBS improvement was associated with Lactobacillus-dominant vaginal microbiota at enrollment (57% vs 22%, P = 0.08). Vaginal glycogen, serum estradiol, and estrone significantly increased in women whose MBS improved. CONCLUSIONS:A larger proportion of women whose MBS improved had a Lactobacillus dominant microbiota at enrollment than those who had no improvement during the trial, though this difference was not statistically significant. Larger trials are needed to determine whether vaginal microbiota modify or mediate treatment responses in women with GSM.

ObjectiveTo examine associations between the composition of the vaginal microbiota and genitourinary menopausal symptoms, serum estrogen, and vaginal glycogen.MethodsFor this cross-sectional study, 88 women aged 40 to 62 years, enrolled in a hot flash treatment trial, provided vaginal swabs and a blood sample at enrollment. Bacterial communities were characterized using 16S rRNA PCR and deep sequencing targeting the V3-V4 region. Quantities of Lactobacillus crispatus and Lactobacillus iners were measured using qPCR. Self-reported genitourinary symptoms included: presence and severity of individual symptoms and identification of most bothersome symptom. Glycogen was measured fluorometrically in swab eluate. Serum estradiol (E2) and estrone (E1) were measured by liquid chromatography/mass spectrometry. Associations between bacteria, symptoms, glycogen, and serum estrogens were tested by linear regression or Wilcoxon signed-rank test, adjusted for multiple comparisons. Comparisons between groups used Kruskall-Wallis or Fisher's exact test.ResultsOf the 88 women, 33 (38%) had a majority of Lactobacillus species, whereas 58 (66%) had any Lactobacillus detected. Over half (53%) reported at least one vulvovaginal symptom (most commonly dryness), but symptoms were not associated with the presence of Lactobacillus species. Women with Lactobacillus-dominant communities had higher unconjugated serum estrone, but no difference in vaginal glycogen levels, compared with those with non-Lactobacillus-dominant communities. Higher serum E2 and E1 were not associated with either higher vaginal glycogen or detection of individual genera.ConclusionsPresence of Lactobacillus-dominant vaginal microbiota was not associated with fewer vulvovaginal symptoms. Serum estrone was higher in women with Lactobacillus dominance, but vaginal-free glycogen was not associated with composition of the vaginal microbiota.

ObjectiveTo examine associations between the composition of the vaginal microbiota and genitourinary menopausal symptoms, serum estrogen, and vaginal glycogen.MethodsFor this cross-sectional study, 88 women aged 40 to 62 years, enrolled in a hot flash treatment trial, provided vaginal swabs and a blood sample at enrollment. Bacterial communities were characterized using 16S rRNA PCR and deep sequencing targeting the V3-V4 region. Quantities of Lactobacillus crispatus and Lactobacillus iners were measured using qPCR. Self-reported genitourinary symptoms included: presence and severity of individual symptoms and identification of most bothersome symptom. Glycogen was measured fluorometrically in swab eluate. Serum estradiol (E2) and estrone (E1) were measured by liquid chromatography/mass spectrometry. Associations between bacteria, symptoms, glycogen, and serum estrogens were tested by linear regression or Wilcoxon signed-rank test, adjusted for multiple comparisons. Comparisons between groups used Kruskall-Wallis or Fisher's exact test.ResultsOf the 88 women, 33 (38%) had a majority of Lactobacillus species, whereas 58 (66%) had any Lactobacillus detected. Over half (53%) reported at least one vulvovaginal symptom (most commonly dryness), but symptoms were not associated with the presence of Lactobacillus species. Women with Lactobacillus-dominant communities had higher unconjugated serum estrone, but no difference in vaginal glycogen levels, compared with those with non-Lactobacillus-dominant communities. Higher serum E2 and E1 were not associated with either higher vaginal glycogen or detection of individual genera.ConclusionsPresence of Lactobacillus-dominant vaginal microbiota was not associated with fewer vulvovaginal symptoms. Serum estrone was higher in women with Lactobacillus dominance, but vaginal-free glycogen was not associated with composition of the vaginal microbiota.

Epigenetic modifications, including DNA methylation, represent a potential mechanism for environmental impacts on human disease. Maternal smoking in pregnancy remains an important public health problem that impacts child health in a myriad of ways and has potential lifelong consequences. The mechanisms are largely unknown, but epigenetics most likely plays a role. We formed the Pregnancy And Childhood Epigenetics (PACE) consortium and meta-analyzed, across 13 cohorts (n = 6,685), the association between maternal smoking in pregnancy and newborn blood DNA methylation at over 450,000 CpG sites (CpGs) by using the Illumina 450K BeadChip. Over 6,000 CpGs were differentially methylated in relation to maternal smoking at genome-wide statistical significance (false discovery rate, 5%), including 2,965 CpGs corresponding to 2,017 genes not previously related to smoking and methylation in either newborns or adults. Several genes are relevant to diseases that can be caused by maternal smoking (e.g., orofacial clefts and asthma) or adult smoking (e.g., certain cancers). A number of differentially methylated CpGs were associated with gene expression. We observed enrichment in pathways and processes critical to development. In older children (5 cohorts, n = 3,187), 100% of CpGs gave at least nominal levels of significance, far more than expected by chance (p value < 2.2 × 10(-16)). Results were robust to different normalization methods used across studies and cell type adjustment. In this large scale meta-analysis of methylation data, we identified numerous loci involved in response to maternal smoking in pregnancy with persistence into later childhood and provide insights into mechanisms underlying effects of this important exposure.