Two Strains of Lactobacilli Effectively Decrease the Colonization of VRE in a Mouse Model

Vancomycin-resistant Enterococcus (VRE) infection is a serious challenge for clinical management and there is no effective treatment at present. Fecal microbiota transplantation (FMT) and probiotic intervention have been shown to be promising approaches for reducing the colonization of certain pathogenic bacteria in the gastrointestinal tract, however, no such studies have been done on VRE. In this study, we evaluated the effect of FMT and two Lactobacillus strains (Y74 and HT121) on the colonization of VRE in a VRE-infection mouse model. We found that both Lactobacilli strains reduced VRE colonization rapidly. Fecal microbiota and colon mRNA expression analyses further showed that mice in FMT and the two Lactobacilli treatment groups restored their intestinal microbiota diversity faster than those in the phosphate buffer saline (PBS) treated group. Administration of Lactobacilli restored Firmicutes more quickly to the normal level, compared to FMT or PBS treatment, but restored Bacteroides to their normal level less quickly than FMT did. Furthermore, these treatments also had an impact on the relative abundance of intestinal microbiota composition from phylum to species level. RNA-seq showed that FMT treatment induced the expression of more genes in the colon, compared to the Lactobacilli treatment. Defense-related genes such as defensin α, Apoa1, and RegIII were down-regulated in both FMT and the two Lactobacilli treatment groups. Taken together, our findings indicate that both FMT and Lactobacilli treatments were effective in decreasing the colonization of VRE in the gut

Prenatal levonorgestrel exposure induces autism-like behavior in offspring through ERβ suppression in the amygdala

Abstract Background Autism spectrum disorder (ASD) is characterized by impairments in social communication and restricted or repetitive behaviors or interests. ASD is now diagnosed in more than one out of 100 children and is biased towards males by a ratio of at least 4:1. Many possible explanations and potential causative factors have been reported, such as genetics, sex, and environmental factors, although the detailed mechanisms of ASD remain unclear. Methods The dams were exposed through oral contraceptives to either vehicle control (VEH) alone, levonorgestrel (LNG) alone, ethinyl estradiol (EE) alone, or a combination of LNG/EE for 21 days during their pregnancy. The subsequent 10-week-old offspring were used for autism-like behavior testing, and the limbic tissues were isolated for analysis. In another experimental group, 8-week-old male offspring were treated by infusion of ERβ overexpression/knockdown lentivirus in the amygdala, and the offspring were analyzed after 2 weeks. Results We show that prenatal exposure of either LNG alone or a LNG/EE combination, but not EE alone, results in suppression of ERβ (estrogen receptor β) and its target genes in the amygdala with autism-like behavior in male offspring, while there is a much smaller effect on female offspring. However, we find that there is no effect on the hippocampus and hypothalamus. Further investigation shows that ERβ suppression is due to LNG-mediated altered methylation on the ERβ promoter and results in tissue damage with oxidative stress and the dysfunction of mitochondria and fatty acid metabolism, which subsequently triggers autism-like behavior. Overexpression of ERβ in the amygdala completely restores LNG-induced ERβ suppression and autism-like behaviors in offspring, while ERβ knockdown mimics this effect, indicating that ERβ expression in the amygdala plays an important role in autism-like behavior development. Conclusions We conclude that prenatal levonorgestrel exposure induces autism-like behavior in offspring through ERβ suppression in the amygdala. To our knowledge, this is the first time the potential effect of oral contraceptives on the contribution of autism-like behavior in offspring has been discovered

Perinatal testosterone exposure potentiates vascular dysfunction by ERβ suppression in endothelial progenitor cells

<div><p>Recent clinical cohort study shows that testosterone therapy increases cardiovascular diseases in men with low testosterone levels, excessive circulating androgen levels may play a detrimental role in the vascular system, while the potential mechanism and effect of testosterone exposure on the vascular function in offspring is still unknown. Our preliminary results showed that perinatal testosterone exposure in mice induces estrogen receptor β (ERβ) suppression in endothelial progenitor cells (EPCs) in offspring but not mothers, while estradiol (E2) had no effect. Further investigation showed that ERβ suppression is due to perinatal testosterone exposure-induced epigenetic changes with altered DNA methylation on the ERβ promoter. During aging, EPCs with ERβ suppression mobilize to the vascular wall, differentiate into ERβ-suppressed mouse endothelial cells (MECs) with downregulated expression of SOD2 (mitochondrial superoxide dismutase) and ERRα (estrogen-related receptor α). This results in reactive oxygen species (ROS) generation and DNA damage, and the dysfunction of mitochondria and fatty acid metabolism, subsequently potentiating vascular dysfunction. Bone marrow transplantation of EPCs that overexpressed with either ERβ or a SIRT1 single mutant SIRT1-C152(D) that could modulate SIRT1 phosphorylation significantly ameliorated vascular dysfunction, while ERβ knockdown worsened the problem. We conclude that perinatal testosterone exposure potentiates vascular dysfunction through ERβ suppression in EPCs.</p></div

Perinatal testosterone exposure potentiates vascular dysfunction in old male offspring (20 months old).

<p>(a-c) The treated male offspring were given a bolus dose of 2mCi of ¹⁴C-OA through oral gavage, and the blood and tissues, including the heart, aorta and liver, were dissected for analysis of total radioactivity. (a) The in vivo ¹⁴C-OA uptake from the heart and aorta in 2h, n = 8. (b) The in vivo ¹⁴C-OA uptake from liver in 2h, n = 7. (c) The in vivo ¹⁴C-OA uptake in plasma in 1h, n = 6. (d-g) The plasma was collected from treated male offspring for analysis of total cholesterol, n = 10 (d); triglyceride, n = 10 (e); LDL cholesterol, n = 12 (f); and HDL cholesterol, n = 11 (g). (h,i) The aortas were dissected from treated mice for vessel tension analysis. The rings were pre-constricted with phenylephrine, and the acetylcholine (Ach, 10⁻¹⁰–10⁻⁴ mol/l) was injected at the plateau of the phenylephrine-induced contraction. (h) The 10⁻⁴ mol/l Ach-induced aorta ring relaxation, n = 9–12; (i) The Ach-induced aorta ring relaxation curves. (j) The treated mice were used to measure the mean of systolic blood pressure, n = 11. *, <i>P</i><0.05, vs CTL group. Results are expressed as mean ± SEM.</p

Perinatal testosterone exposure suppresses ERβ expression and its target genes in EPCs in young offspring (2 months old).

<p>2-month old female mice were exposed to 5mg of 60-day release hormone pellets that contained either dihydrotestosterone (DHT) alone, estradiol (E2) alone, combined DHT and E2 (DHT/E2), or controlled vehicle (CTL) during a 7-week perinatal period. The mothers were sacrificed to measure the plasma hormone levels, and the MNCs (including EPCs and non-EPCs) were isolated from either the bone marrow or peripheral blood for analysis of gene expression. The male offspring was also sacrificed at 2 months old for isolation of MNCs (including EPCs and non-EPCs) for further analysis. (a) Dihydrotestosterone (DHT) level in plasma from mothers, n = 8. (b) The estradiol (E2) level in plasma from mothers, n = 8. (c) The ERβ mRNA in BM-derived MNCs from mothers, n = 7. (d) The ERβ mRNA in Circulating MNCs from mothers, n = 7. (e)The ERβ mRNA in BM-derived MNCs from male offspring, n = 6. (f) The ERβ mRNA in Circulating MNCs from male offspring, n = 6. (g) The mRNA levels in BM-derived EPCs from male offspring, n = 7. (h) The mRNA levels in Circulating EPCs from male offspring, n = 7. *, <i>P</i><0.05, vs CTL group; ¶, <i>P</i><0.05, vs DHT group; #, <i>P</i><0.05, vs DHT/E2 group. Results are expressed as mean ± SEM.</p

Bone marrow transplantation with ERβ overexpression in EPCs restores perinatal testosterone exposure-induced vascular dysfunction in male old offspring, while ERβ knockdown in EPCs worsens the problem.

<p>(a-c) The treated mice were given a bolus dose of 2mCi of ¹⁴C-OA through oral gavage, and the blood and tissues, including the heart, aorta and liver, were dissected for analysis of total radioactivity. (a) The in vivo ¹⁴C-OA uptake from the heart and aorta in 2h, n = 6. (b) The in vivo ¹⁴C-OA uptake from liver in 2h, n = 6. (c) The in vivo ¹⁴C-OA uptake in plasma in 1h, n = 7. (c) (d-g) The plasma was collected from treated mice for analysis of total cholesterol, n = 9 (d); triglyceride, n = 8 (e); LDL cholesterol, n = 11 (f); and HDL cholesterol, n = 12 (g). (h,i) The aortas were dissected from treated mice for vessel tension analysis. The rings were pre-constricted with phenylephrine, and the acetylcholine (Ach, 10⁻¹⁰–10⁻⁴ mol/l) was injected at the plateau of the phenylephrine-induced contraction. (h) The 10⁻⁴ mol/l Ach-induced aorta ring relaxation, n = 8–11; (i) The Ach-induced aorta ring relaxation curves. (j) The treated mice were used to measure the mean of systolic blood pressure, n = 10. *, <i>P</i><0.05, vs CTL group; ¶, <i>P</i><0.05, vs DHT group. Results are expressed as mean ± SEM.</p

Perinatal testosterone exposure induces ERβ suppression and its target genes from both circulating EPCs and mouse endothelial cells (MECs) in old male offspring (20 months old).

<p>(a-c). The EPCs were isolated from treated male offspring for further analysis. (a) mRNA level by qPCR, n = 4. (b) Protein level by western blotting, n = 4. (c) The representative bands for (b). (d) The MECs were isolated from the aorta using Laser Capture Microdissection (LCM) techniques to measure mRNA level by qPCR, n = 5. (e,f) The MECs were isolated from the heart and cultured in vitro for protein analysis using western blotting. (e) Protein level by Western blotting, n = 4. (f) Representative bands for (e). *, <i>P</i><0.05, vs CTL group. Results are expressed as mean ± SEM.</p