Effects of Varied Sulfamethazine Dosage and Exposure Durations on Offspring Mice.

The development of antibiotics was a turning point in the history of medicine; however, their misuse and overuse have contributed to the current global epidemic of antibiotic resistance. According to epidemiological studies, early antibiotic exposure increases the risk of immunological and metabolic disorders. This study investigated the effects of exposure to different doses of sulfamethazine (SMZ) on offspring mice and compared the effects of exposure to SMZ on offspring mice in prenatal and early postnatal periods and continuous periods. Furthermore, the effects of SMZ exposure on the gut microbiota of offspring mice were analyzed using metagenome. According to the results, continuous exposure to high-dose SMZ caused weight gain in mice. IL-6, IL-17A, and IL-10 levels in the female offspring significantly increased after high-dose SMZ exposure. In addition, there was a significant gender difference in the impact of SMZ exposure on the gut microbiota of offspring: Continuous high-dose SMZ exposure significantly decreased the relative abundance of Ligilactobacillus murinus, Limosilactobacillus reuteri, Lactobacillus johnsonii, and Bifidobacterium pseudolongum (p < 0.05) in female offspring mice; however, these significant changes were not observed in male offspring mice.

Uncovering Predictive Factors and Interventions for Restoring Microecological Diversity after Antibiotic Disturbance.

Antibiotic treatment can lead to a loss of diversity of gut microbiota and may adversely affect gut microbiota composition and host health. Previous studies have indicated that the recovery of gut microbes from antibiotic-induced disruption may be guided by specific microbial species. We expect to predict recovery or non-recovery using these crucial species or other indices after antibiotic treatment only when the gut microbiota changes. This study focused on this prediction problem using a novel ensemble learning framework to identify a set of common and reasonably predictive recovery-associated bacterial species (p-RABs), enabling us to predict the host microbiome recovery status under broad-spectrum antibiotic treatment. Our findings also propose other predictive indicators, suggesting that higher taxonomic and functional diversity may correlate with an increased likelihood of successful recovery. Furthermore, to explore the validity of p-RABs, we performed a metabolic support analysis and identified Akkermansia muciniphila and Bacteroides uniformis as potential key supporting species for reconstruction interventions. Experimental results from a C57BL/6J male mouse model demonstrated the effectiveness of p-RABs in facilitating intestinal microbial reconstitution. Thus, we proved the reliability of the new p-RABs and validated a practical intervention scheme for gut microbiota reconstruction under antibiotic disturbance.

Metagenomic insights into the effects of cosmetics containing complex polysaccharides on the composition of skin microbiota in females.

Introduction: The use of cosmetics has become a habit for women. However, their influence on the microbial diversity of the skin has rarely been studied. Methods: Herein, the effect of cosmetics containing complex polysaccharides on the skin bacterial microbiota of female forehead and cheek areas was analyzed. Eighty volunteers were recruited and split into two groups (40 people each); one group was treated with cosmetics containing complex polysaccharides and the other with basic cream for 28 days. Skin samples were collected using sterilized cotton swabs, and 16S rDNA high-throughput sequencing was used to analyze the changes in skin bacterial microbiota composition before and after the intervention. Results and discussion: A total of twenty-four phyla were detected in the forehead and cheek skin samples of 80 volunteers, the top three of which were Proteobacteria, Firmicutes, and Actinobacteria. The main genera of the forehead skin bacterial microbiota were Cutibacterium (11.1%), Acinetobacter (10.4%), Enterococcus (8.9%), Ralstonia (8.8%), and Staphylococcus (8.7%), while those of the cheek skin bacterial microbiota were Staphylococcus (20.0%), Ralstonia (8.7%), Propionibacterium (7.9%), Acinetobacter (7.2%), and Bifidobacterium (6.0%). Compared with basic cream, the use of cosmetics containing complex polysaccharides significantly increased the relative abundance of Staphylococcus and Bacillus in the forehead and cheek and reduced the relative abundance of Propionibacterium and Bifidobacterium. Thus, cosmetics containing complex polysaccharides could modify the composition of skin bacterial microbiota, which may help to maintain stable conditions of the skin.

Efficacy of Probiotic Compounds in Relieving Constipation and Their Colonization in Gut Microbiota.

A number of studies have confirmed the relationship between constipation and gut microbiota. Additionally, many human and animal experiments have identified probiotics as effectors for the relief of constipation symptoms. In this study, probiotic compounds, including Lactobacillus acidophilus LA11-Onlly, Lacticaseibacillus rhamnosus LR22, Limosilactobacillus reuteri LE16, Lactiplantibacillus plantarum LP-Onlly, and Bifidobacterium animalis subsp. lactis BI516, were administered to mice with loperamide-induced constipation, and the impacts of these strains on constipation-related indicators and gut microbiota were evaluated. The effects of probiotic compounds on constipation relief were associated with various aspects, including gastrointestinal transit rate, number and weight of stools, serum and intestinal gastrointestinal regulatory hormones, and serum cytokines. Some of the probiotic compounds, including Limosilactobacillus reuteri, Lactiplantibacillus plantarum, and Lacticaseibacillus rhamnosus, were found to colonize the intestinal tract. Furthermore, higher dosages promoted the colonization of specific strains. This study yields a new perspective for the clinical use of probiotics to improve constipation symptoms by combining strains with different mechanisms for the alleviation of constipation.

Predicting the Role of the Human Gut Microbiome in Constipation Using Machine-Learning Methods: A Meta-Analysis.

(1) Background: Constipation is a common condition that affects the health and the quality of life of patients. Recent studies have suggested that the gut microbiome is associated with constipation, but these studies were mainly focused on a single research cohort. Thus, we aimed to construct a classification model based on fecal bacterial and identify the potential gut microbes' biomarkers. (2) Methods: We collected 3056 fecal amplicon sequence data from five research cohorts. The data were subjected to a series of analyses, including alpha- and beta-diversity analyses, phylogenetic profiling analyses, and systematic machine learning to obtain a comprehensive understanding of the association between constipation and the gut microbiome. (3) Results: The alpha diversity of the bacterial community composition was higher in patients with constipation. Beta diversity analysis evidenced significant partitions between the two groups on the base of gut microbiota composition. Further, machine learning based on feature selection was performed to evaluate the utility of the gut microbiome as the potential biomarker for constipation. The Gradient Boosted Regression Trees after chi2 feature selection was the best model, exhibiting a validation performance of 70.7%. (4) Conclusions: We constructed an accurate constipation discriminant model and identified 15 key genera, including Serratia, Dorea, and Aeromonas, as possible biomarkers for constipation.

A new Illumina MiSeq high-throughput sequencing-based method for evaluating the composition of the Bacteroides community in the intestine using the rpsD gene sequence.

Bacteroides is a bacterial genus that is known to closely interact with the host. The potential role of this genus is associated with its ecological status and distribution in the intestine. However, the current 16S V3-V4 region sequencing method can only detect the abundance of this genus, revealing a need for a novel sequencing method that can elucidate the composition of Bacteroides in the human gut microbiota. In this study, a core gene, rpsD, was selected as a template for the design of a Bacteroides-specific primer set. We used this primer set to develop a novel assay based on the Illumina MiSeq sequencing platform that enabled an accurate assessment of the Bacteroides compositions in complex samples. Known amounts of genomic DNA from 10 Bacteroides species were mixed with a complex sample and used to evaluate the performance and detection limit of our assay. The results were highly consistent with those of direct sequencing with a low Bacteroides DNA detection threshold (0.01 ng), supporting the reliability of our assay. In addition, the assay could detect all the known Bacteroides species within the faecal sample. In summary, we provide a sensitive and specific approach to determining the Bacteroides species in complex samples.

The diversity of gut microbiota in type 2 diabetes with or without cognitive impairment.

BACKGROUND: Diabetes is associated with a high risk of developing cognitive impairment, but the underlying mechanism remains unclear. Recent studies have found that gut microbiota may be involved in the progression of diabetes-associated cognitive impairment. AIMS: To analyze the diversity of gut microbiota in type 2 diabetes with or without cognitive impairment METHODS: 16S rRNA sequencing was used to detect the gut microbiota composition in 154 type 2 diabetes (T2DM) subjects RESULTS: Among 154 elderly T2DM participants included in our study, 73 with normal and 81 with impaired cognition. Lower levels of hemoglobin and HDL were observed in subjects with cognitive impairment. Patients with cognitive impairment had a lower abundance of Tenericutes. Comparison at the genus level revealed that T2DM patients with cognitive impairment had a decreased abundance of Bifidobacterium and unranked-RF39 and an increased abundance of Peptococcus and unranked-Leuconostocaceae. Additionally, the relative abundance of Veillonella and Pediococcus were decreased in subjects with cognitive impairment. Furthermore, the relative abundance of 7 sub-functions was significantly changed in the group with cognitive impairment. Calcium signaling pathways and the Renin-angiotensin system were upregulated in the cognitive impairment group while GnRH signaling, Fc gamma R-mediated phagocytosis, endocytosis, isoflavonoid biosynthesis, and cytochrome P450 were deregulated. CONCLUSION: Bifidobacterium may be associated with cognition in T2DM. Calcium signaling and renin-angiotensin system were shown to be associated with diabetes-associated cognitive impairment through gut microbiota.

groEL Gene-Based Phylogenetic Analysis of Lactobacillus Species by High-Throughput Sequencing.

Lactobacillus is a fairly diverse genus of bacteria with more than 260 species and subspecies. Many profiling methods have been developed to carry out phylogenetic analysis of this complex and diverse genus, but limitations remain since there is still a lack of comprehensive and accurate analytical method to profile this genus at species level. To overcome these limitations, a Lactobacillus-specific primer set was developed targeting a hypervariable region in the groEL gene-a single-copy gene that has undergone rapid mutation and evolution. The results showed that this methodology could accurately perform taxonomic identification of Lactobacillus down to the species level. Its detection limit was as low as 104 colony-forming units (cfu)/mL for Lactobacillus species. The assessment of detection specificity using the LactobacillusgroEL profiling method found that Lactobacillus, Pediococcus, Weissella, and Leuconostoc genus could be distinguished, but non-Lactobacillus Genus Complex could not be detected. The groEL gene sequencing and Miseq high-throughput approach were adopted to estimate the richness and diversity of Lactobacillus species in different ecosystems. The method was tested using kurut (fermented yak milk) samples and fecal samples of human, rat, and mouse. The results indicated that Lactobacillus mucosae was the predominant gut Lactobacillus species among Chinese, and L. johnsonii accounted for the majority of lactobacilli in rat and mouse gut. Meanwhile, L. delbrueckii subsp. bulgaricus had the highest relative abundance of Lactobacillus in kurut. Thus, this groEL gene profiling method is expected to promote the application of Lactobacillus for industrial production and therapeutic purpose.

Assessment of Bifidobacterium Species Using groEL Gene on the Basis of Illumina MiSeq High-Throughput Sequencing.

The next-generation high-throughput sequencing techniques have introduced a new way to assess the gut's microbial diversity on the basis of 16S rRNA gene-based microbiota analysis. However, the precise appraisal of the biodiversity of Bifidobacterium species within the gut remains a challenging task because of the limited resolving power of the 16S rRNA gene in different species. The groEL gene, a protein-coding gene, evolves quickly and thus is useful for differentiating bifidobacteria. Here, we designed a Bifidobacterium-specific primer pair which targets a hypervariable sequence region within the groEL gene that is suitable for precise taxonomic identification and detection of all recognized species of the genus Bifidobacterium so far. The results showed that the novel designed primer set can specifically differentiate Bifidobacterium species from non-bifidobacteria, and as low as 104 cells of Bifidobacterium species can be detected using the novel designed primer set on the basis of Illumina Miseq high-throughput sequencing. We also developed a novel protocol to assess the diversity of Bifidobacterium species in both human and rat feces through high-throughput sequencing technologies using groEL gene as a discriminative marker.

Elevation in Total Homocysteine Levels in Chinese Patients With Essential Hypertension Treated With Antihypertensive Benazepril.

OBJECTIVE: To investigate the effect of benazepril on plasma homocysteine (Hcy) levels and to analyze the correlation between the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and changes in Hcy levels in response to benazepril. METHODS: A total of 231 patients with mild to moderate essential hypertension were enrolled, and benazepril was orally administered at a dose of 10 mg/d for 2 weeks. Plasma Hcy levels were measured by high-performance liquid chromatography at baseline and after 2 weeks of treatment. Genotyping of the MTHFR C677T polymorphism was performed by TaqMan probe technique. RESULTS: There was no significant change in Hcy level after benazepril treatment for 2 weeks (P = .97). However, stratified by baseline Hcy levels, the patients with baseline Hcy <10 µmol/L had a significant increase in plasma Hcy levels (P = .003). The results from the multivariable linear regression analysis demonstrated a significant correlation between baseline Hcy levels and the changes in Hcy levels found in both the unadjusted (P = .002) and the adjusted model (P = .004). Strikingly, we found no significant effect modification by the MTHFR C677T polymorphism on the Hcy changes after benazepril treatment. There were also no statistically significant interactions of gene and environment factors (ie, gene smoking and drinking) on the changes in Hcy levels after benazepril treatment. CONCLUSION: Benazepril may cause an increase in plasma Hcy levels among patients with hypertension with low baseline Hcy levels, while effect modification by MTHFR C677T genotypes on the changes in Hcy levels in response to benazepril was not significant among patients with essential hypertension.

Joint associations of folate, homocysteine and MTHFR, MTR and MTRR gene polymorphisms with dyslipidemia in a Chinese hypertensive population: a cross-sectional study.

BACKGROUND: Dyslipidemia is a well-established risk factor for cardiovascular disease. Serum lipids were affected by several gene polymorphisms, folate, homocysteine and other metabolite levels. We aim to investigate the effects of homocysteine metabolism enzyme polymorphisms (MTHTR C677T, MTHFR A1298C, MTR A2756G and MTRR A66G) and their interactions with folate, homocysteine on serum lipid levels in Chinese patients with hypertension. METHODS: Participants were 480 hypertensive adults that enrolled in September to December 2005 from six different Chinese hospitals (Harbin, Shanghai, Shenyang, Beijing, Xi'an, and Nanjing). Known MTHFR C677T, MTHFR A1298C, MTR A2756G and MTRR A66G genotypes were determined by PCR-RFLP methods. Serum folate was measured by chemiluminescent immunoassay, homocysteine was measured by high-performance liquid chromatography, serum lipids parameters were determined by an automatic biochemistry analyzer, low-density lipoprotein was calculated by Friedewald's equation. Unitary linear regression model was used to assess the associations of gene polymorphisms, folate and homocysteine on serum lipid profiles. Unconditional logistic regression model was applied to test the interactions of folate, homocysteine and gene polymorphisms on dyslipidemia. RESULTS: No correlations between gene polymorphisms and homocysteine on serum lipid profiles. Compared with normal folate patients, patients with low folate showed higher odds of hypertriglyceridemia (OR = 2.02, 95 % CI: 1.25-3.25, P = 0.004) and low levels of high-density lipoprotein cholesterol (OR = 1.88, 95 % CI: 1.07-3.28, P = 0.027). Each of four gene polymorphisms (MTHTR C677T, MTHFR A1298C, MTR A2756G and MTRR A66G) combined with low folate showed higher odds of hypertriglyceridemia (P for trend: 0.049, 0.004, 0.007 and 0.005, respectively). MTHFR C677T and A1298C with low folate showed higher odds of low levels of high-density lipoprotein cholesterol (P for trend: 0.008 and 0.031). CONCLUSIONS: Low folate status and homocysteine metabolism gene polymorphisms (MTHTR C677T, MTHFR A1298C, MTR A2756G and MTRR A66G) may have a synergistic effect increased the incidence of dyslipidemia in Chinese hypertensive population.

Associations of MTHFR and MTRR polymorphisms with serum lipid levels in Chinese hypertensive patients.

OBJECTIVE: To examine the effects of the methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) gene polymorphisms and their interactions with environmental factors on serum lipid levels. METHODS: We investigated totally 340 patients with essential hypertension, from Dongzhi community, Anhui, China. High-throughput TaqMan allelic discrimination assay was used for the genotyping of MTHFR C677T (Ala222Val), MTHFR A1298C (Glu429Ala), MTRR A66G (Ile22Met), and MTRR His595Tyr. RESULTS: Compared with the MTRR 66AA genotype carriers, the GG genotype carriers had lower serum total cholesterol (TC) levels (adjusted ß ± standard error [SE]: -0.5 ± 0.2 mmol/L; P = .003) and low-density lipoprotein cholesterol (LDL-C) levels (adjusted ß ± SE: -0.4 ± 0.2 mmol/L; P = .005). Their false discovery rate (FDR)-adjusted P values were 0.056 and 0.056, respectively. We further found that there was a statistically significant interaction between 677TT genotype and sex in their associations with LDL levels (P interaction = .020), and significant interaction between 677TT genotype and smoking on LDL levels (P interaction = .036). A similar pattern of interaction was found between 66GG and drinking on levels of TC (P interaction = .034) and LDL (P interaction = .020). However, there were no significant interactions observed after FDR adjustment. CONCLUSION: Both MTHFR and MTRR gene polymorphisms could be important genetic determinants of serum lipid levels in Chinese patients with hypertension. These findings need to be replicated in a larger sample.