Yajuan Xu

The aim of this study is to conduct a multi-omics investigation of the metabolic profile of hypothyroidism in the first half of pregnancy and its correlation with the Th17/Treg balance.30 pregnant women with hypothyroidism (hypothyroidism group) and 30 healthy pregnant women (control group) in the first half of pregnancy were included. Results showed that sphingosine (Sph) and BH3 interacting domain death agonist (BID) were significantly upregulated in hypothyroidism group. Sphingolipid signaling pathway was the significantly enriched pathway. Sph and BID in cord blood of hypothyroidism group were also higher. An increase was shown in the Th17/Treg ratio and Th17 cells, and a decrease shown in Treg cells in the hypothyroidism group. The incidence of gestational diabetes mellitus in the hypothyroidism group was significantly higher. Sph and BID were positively correlated with Th17/Treg ratio. Sph levels were positively correlated with Th17 percentage and gestational diabetes.In conclusion, using a multi-omics approach, we identified distinct metabolic alterations in women with hypothyroidism in the first half of pregnancy, characterized by elevated levels of sphingosine and BID and a disrupted Th17/Treg balance. These changes may contribute to the pathogenesis of early gestational hypothyroidism, offering new theoretical insights into its underlying mechanisms.

Gestational subclinical hypothyroidism (SCH), marked by elevated Thyroid-stimulating hormone (TSH) with normal free thyroxine (FT4), links to adverse perinatal outcomes. During early pregnancy (< 20 weeks), maternal thyroid hormones are crucial for fetal neurodevelopment, with deficiencies risking irreversible deficits. SCH pregnancies show gut microbiota alterations and metabolic dysregulation. Emerging evidence suggests these changes may drive Th(helper T cells)1/Th2/Th17 immune imbalance, though mechanisms remain unclear. This study combines metagenomics and lipidomics to investigate gut microbiota-Th1/Th2/Th17 interactions in patients with SCH in the first 20 weeks during pregnancy. This study included 20 pregnant women with SCH (SCH group) in the first half of pregnancy (≤ 20 gestational weeks) and 20 normal pregnant women (CON group) in the same period. Collect fecal and blood samples from both groups. Metagenomic sequencing was used to determine the differences in the composition of the intestinal microbiota between the two groups, and non-targeted lipidomics was used to compare the lipid differences between the two groups. Flow cytometry was used to assess Th1, Th2 and Th17 cells in peripheral blood, and a cell microbead array was used to determine cytokine levels. (1) Metagenomic sequencing showed an increased abundance of Faecalibacterium prausnitzii and a decreased abundance of Bacteroides uniformis in the SCH group. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated significant enrichment in lipid and polysaccharide biosynthesis and mucopolysaccharide biodegradation pathways in the SCH group. (2) Lipidomics identified 692 different lipids, with Triglyceride (TG) being the most significant. KEGG pathway analysis revealed that TG was mainly concentrated in the Th1, Th2, and Th17 cell differentiation pathways. (3) Additionally, serological indicators of the two groups showed that TSH, Interleukin (IL)-2,IL-10, Tumor necrosis factor (TNF)-α, TG, Th1, and Th17 in the SCH group were higher than those in the CON group, while Th2 was significantly lower (P < 0.05). In the first half of pregnancy, patients with SCH may experience intestinal microbiota disorder, characterized by increased levels of Faecalibacterium prausnitzii and decreased levels of Bacteroides uniformis, at the same time, it was accompanied by an increase in TG synthesis and a Th1/Th2/Th17 imbalance, these factors may be involved in the occurrence of SCH during pregnancy.

Objective: To explore the gut microbiota and proteomic characteristics of hypothyroidism in the first half of pregnancy (referred to as hypothyroidism in the first half of pregnancy) and its association with Th (T helper cells, Th)1/Th2 balance using metagenomics combined with proteomics.Methods: Stool and blood samples were collected from 20 hypothyroid (hypothyroidism group) and normal pregnant women (normal group) in the first half of pregnancy. Flora and proteomic characteristics were analyzed using metagenomics sequencing and 4D-DIA proteomics. Th1 and Th2 cells were quantified, and cytokine levels were measured using cellular micro-bead arra. The enzyme-linked immunosorbent test (ELISA) was utilized to assess differential proteins.Results: (1) Metagenomic sequencing revealed distinct microbial profiles: The β-diversity of gut microbiota was diminished in the hypothyroidism group (p < 0.05). LEfSe analysis identified Phocaeicola vulgatus and Bacteroides fragilis enriched in the hypothyroidism group (pP. vulgatus and B. fragilis, decreased DGKK and S10A8 proteins, and a left shift in the Th1/Th2 balance in patients with hypothyroidism in the first half of pregnancy may be associated with the development of the disease.

374 pregnant women with isolated hypothyroxinemia (IH) who were ≤ 20 weeks were included retrospectively in this study. Based on the confirmed gestational age and the use of levothyroxine (LT4), the patients were divided into the treated group (T1 group) and untreated group (C1 group) in first trimester (≤ 13^+ 6 weeks), the treated group(T2 group) and untreated group (C2 group) in second trimester (14–20 weeks). Data on thyroid function and lipid indices was collected both before and after LT4 treatment. To compare the thyroid function, lipid indices and pregnancy outcomes after LT4 treatment. There was a negative correlation between FT4 levels and TC and LDL levels in the first trimester (PP < 0.05). FT4 levels in T2 group were higher than C2 group, and there was no significant difference in other indicators. The risk of spontaneous abortion, gestational diabetes mellitus (GDM) and macrosomia in T1 group was significantly decreased (P < 0.05), and there was no significant difference between T2 and C2 groups. Thus, LT4 treatment can improve the level of FT4 and lipids and reduce adverse pregnancy outcomes in women with IH in the first trimester.

Objective: This study aimed to explore the correlation between microbiota dysbiosis and hypothyroidism in early pregnancy by 16S rRNA amplicon sequencing combined with metagenomic sequencing.Methods: Sixty pregnant women (30 with hypothyroidism and 30 normal controls) were recruited for 16S rRNA amplicon sequencing, and 6 patients from each group were randomly selected for metagenomic sequencing to assess the gut microbiome profile.Results: The 16S rRNA results showed that beta-diversity in the hypothyroidism group was decreased. The relative abundances of the Prevotella and Paraprevotella genera increased in the hypothyroidism group, and Blautia predominated in the controls. The metagenomics results revealed that Prevotella_stercorea_CAG_629, Prevotella_hominis, Prevotella_sp_AM34_19LB, etc. were enriched in the hypothyroidism group at the species level. Functional analysis revealed that the pyridoxal 5’-phosphate synthase pdxT subunit module was decreased, and the short-chain fatty acid (SCFA) transporter and phospholipase/carboxylesterase modules were strongly enriched in the hypothyroidism group. Hypothyroidism patients had increased C-reactive protein (CRP), interleukin-2 (IL-2), IL-4, IL-10, and tumor necrosis factor (TNF)-α levels. The pyridoxal 5’-phosphate synthase pdxT subunit, the SCFA transporter, and the phospholipase/carboxylesterase module were associated with different Prevotella species.Conclusion: In early pregnancy, women with hypothyroidism exhibit microbiota dysbiosis, and Prevotella may affect the metabolism of glutamate, SCFA, and phospholipases, which could be involved in the development of hypothyroidism during pregnancy.

The objective was to investigate the efficacy of different doses of levothyroxine therapy among pregnant women exhibiting high-normal thyroid stimulating hormone levels and positive thyroid peroxidase antibodies throughout the first half of pregnancy. Pregnant women exhibiting high-normal thyroid stimulating hormone levels and thyroid peroxidase antibodies positivity throughout the initial half of pregnancy were selected from January 2021 to September 2023. Based on the different doses of levothyroxine, the pregnant women were categorized into the nonintervention group (G0, 122 women), 25 µg levothyroxine intervention group (G25, 69 women), and 50 µg levothyroxine intervention group (G50, 58 women). Serum parameters, gastrointestinal symptoms, small intestinal bacterial overgrowth (SIBO), maternal and neonatal outcomes were compared after the intervention among the three groups. After the intervention, in the G25 and G50 groups, the thyroid stimulating hormone, triglyceride and low-density lipoprotein levels were notably less in contrast to those in the G0 group (P < 0.05). The rates of abdominal distension and SIBO in the G25 and G50 groups were notably lower in contrast to the G0 group (P = 0.043 and 0.040, respectively). The G50 group had a lower rate of spontaneous abortion and premature membrane rupture than the G0 group (P = 0.01 and 0.015, respectively). Before 11+ 2 weeks of gestation and at thyroid peroxidase antibodies levels ≥ 117 IU/mL, in contrast to the G0 group, the G50 group experienced a decreased rate of spontaneous abortion (P = 0.008). The G50 group had significantly higher newborn weight than the G0 group (P = 0.014), as well as a notably longer newborn length than the G0 and G25 groups (P = 0.005). For pregnant women with high-normal thyroid stimulating hormone levels and thyroid peroxidase antibodies positive during the first half of pregnancy, supplementation with 50 µg levothyroxine was more effective in improving their blood lipid status and gastrointestinal symptoms, reducing the incidence of SIBO and premature rupture of membranes, and before 11+2 weeks, TPOAb ≥ 117 IU/mL proved more beneficial in mitigating the risk of spontaneous abortion.

The aim of this study was to investigate the association between hypothyroidism in early pregnancy and small intestinal bacterial overgrowth (SIBO) and the effect of probiotics. Patients with hypothyroidism in early pregnancy and normal pregnant women during the same period were included in the methane–hydrogen breath test to compare the incidence of SIBO, smoothed curve fit, and differences in clinical symptoms. For those who combined with SIBO, the rate of clinical symptom conversion, thyroid hormones, and changes in associated inflammatory indexes were compared after 21 days of treatment with probiotics on top of conventional levothyroxine sodium tablets. The results are as follows: (1) The incidence of combined SIBO in patients with hypothyroidism in pregnancy was 56.0%, significantly higher than the 28.0% of normal pregnant women during the same period. (2) The highest value of hydrogen plus methane gas in 90 min in pregnancy hypothyroid patients showed a significant negative correlation with FT4 (p < .001, SD = 0.169). (3) Abdominal distension symptoms were significantly increased in both groups after combined SIBO (p = .036, p = .025), and the conversion rate after treatment was 69.2% and 75.0%, respectively. (4) In hypothyroidism, pregnancy combined with SIBO, TSH, and CRP was higher before treatment (p = .001, p = .012) and decreased significantly after treatment (p = .001, p = .008). Hypothyroidism in early pregnancy is associated with SIBO, and probiotic treatment is significantly effective.

Evaluating efficacy of probiotics combined with prebiotics in small intestinal bacterial overgrowth (SIBO) in subclinical hypothyroidism (SCH) in the second trimester. We collected data from 78 pregnant women with SCH (SCH group) and 74 normal pregnant women (control group) in second trimester, compare the differences in high sensitivity C-reactive protein (hsCRP), result of lactulose methane-hydrogen breath test and gastrointestinal symptoms assessed by GSRS scale between two groups. In SCH group, 32 patients with SIBO were selected as intervention group. Treatment with probiotics + prebiotics for 21 days; The differences of lipid metabolism, hsCRP, thyroid function level, methane-hydrogen breath test results and GSRS scores before and after treatment were compared to evaluate the therapeutic effect. (1) The positive rate of SIBO and methane, hsCRP levels in SCH group were higher than those in control group (P < 0.05), the total score of GSRS scale, mean score of indigestion syndrome, and constipation syndrome in SCH group were higher (P < 0.05). (2) The mean abundance of hydrogen and methane were higher in SCH group. (3) After treatment, serum levels of thyrotropin(TSH), total cholesterol(TC), triglyceride(TG), low-density lipoprotein (LDL), and hsCRP in intervention group were decreased, and high-density lipoprotein (HDL) was increased compared with before treatment (P < 0.05). (4) After treatment, methane positive rate, total score of GSRS scale, mean score of diarrhea syndrome, dyspepsia syndrome, and constipation syndrome were decreased (P < 0.05). (5) The average abundance of methane and hydrogen were lower. Probiotics combined with prebiotics are effective in the treatment of SIBO in pregnant SCH patients.Clinical Trial Registration Number: ChiCTR1900026326.

Objective: This study aimed to investigate the relationship between intestinal microflora characteristics and the peripheral blood T helper cell (Th)1/Th2 balance in patients with hypothyroidism during the first half of pregnancy.Methods: The Th1/Th2 ratios in the peripheral blood of pregnant women in the hypothyroidism and control groups were determined using flow cytometry. The cytometric bead array assay was used to determine the serum levels of interleukin-2 (IL-2), IL-4, IL-6, IL-10, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ. Moreover, 16S rRNA amplicon sequencing was used to determine the intestinal microbial composition in the two groups. Finally, the relationships between intestinal microflora, Th1/Th2 cells, cytokines, and clinical indicators were analyzed.Results: C-reactive protein levels were higher in the hypothyroidism group than in the control group. In contrast to the control group, the hypothyroidism group showed an increase in Th1 cells and the Th1/Th2 ratio, and a decrease in Th2 cells. The hypothyroidism group had higher serum IL-2, TNF-α, and IFN-γ levels, and lower IL-10 levels, than the control group. The richness of the intestinal microflora in the hypothyroidism group increased whereas the diversity decreased. The linear discriminant analysis effect size revealed that the hypothyroidism group had a higher abundance of Prevotella and Faecalibacterium, but a lower abundance of Bacteroides, compared to the control group. Prevotella was positively correlated with Th1 cells, the Th1/2 ratio, and TNF-α. Bacteroides was positively correlated with Th2 cells and IL-10, but negatively correlated with Th1 cells, the Th1/2 ratio, TNF-α, and IFN-γ. The thyroid peroxidase antibody level was directly proportional to TNF-α.Conclusion: A Th1/Th2 imbalance occurs in patients with hypothyroidism during the first half of pregnancy. Disorders of the intestinal microflora may lead to hypothyroidism during pregnancy by affecting the Th1/Th2 balance.

Objective: Evaluating efficacy of probiotics combined with prebiotics in small intestinal bacterial overgrowth (SIBO) in subclinical hypothyroidism (SCH) in the second trimester. Methods: We collected data from 78 pregnant women with SCH(SCH group)and 74 normal pregnant women(Control group) in second trimester，compare the differences in high sensitivity C-reactive protein (hsCRP), result of lactulose methane-hydrogen breath test and gastrointestinal symptoms assessed by GSRS scale between two groups.In SCH group, 32 patients with SIBO were selected as Intervention group. Treatment with probiotics + prebiotics for 21 days; The differences of lipid metabolism, hsCRP, thyroid function level, methane-hydrogen breath test results and GSRS scores before and after treatment were compared to evaluate the therapeutic effect. Results: 1. The positive rate of SIBO and methane，hsCRP levels in SCH group were higher than those in control group(P Clinical Trial Registration Number: ChiCTR1900026326