The preparation and application of N-terminal 57 amino acid protein of the follicle-stimulating hormone receptor as a candidate male contraceptive vaccine

Follicle-stimulating hormone receptor （FSHR）, which is expressed only on Sertoli cells and plays a key role in spermatogenesis, has been paid attention for its potential in male contraception vaccine research and development. This study introduces a method for the preparation and purification of human FSHR 57-amino acid protein （FSHR-57aa） as well as determination of its immunogenicity and antifertility effect. A recombinant pET-28a（＋）-FSHR-57aa plasmid was constructed and expressed in Escherichia coil strain BL21 StarTM （DE3） and the FSHR-57aa protein was separated and collected by cutting the gel and recovering activity by efficient refolding dialysis. The protein was identified by Western blot and high-performance liquid chromatography analysis with a band of nearly 7 kDa and a purity of 97.4%. Male monkeys were immunized with rhFSHR-57aa protein and a gradual rising of specific serum IgG antibody was found which reached a plateau on day 112 （16 weeks） after the first immunization. After mating of one male with three female monkeys, the pregnancy rate of those mated with males immunized against FSHR-57aa was significantly decreased while the serum hormone levels of testosterone and estradiol were not disturbed in the control or the FSHR-57aa groups. By evaluating pathological changes in testicular histology, we found that the blood-testis barrier remained intact, in spite of some small damage to Sertoli cells. In conclusion, our study demonstrates that the rhFSHR-57aa protein might be a feasible male contraceptive which could affect sperm production without disturbing hormone levels.

Follicle-stimulating hormone autoantibody is involved in idiopathic spermatogenic dysfunction

Aim： To detect the anti-follicle-stimulating hormone （FSH） antibody in idiopathic infertile patients and fertile subjects in order to determine the role of this antibody in patients with spermatogenic dysfunction. Methods： The anti-FSH antibody in serum was detected by an enzyme-linked immunosorbent assay （ELISA）. The functional and structural integrity of the sperm membrane was evaluated with hypo-osmotic swelling （HOS） test and the ultrastructure of the spermatozoa was investigated by transmission electron microscopy （TEM）. Results： The extent of positive FSH antibody in the patients with oligozoospermia and/or asthenozoospermia was significantly higher than that in the fertile subjects and infertile patients with normal sperm concentration and motility, but it was significantly lower than that in the patients with azoospermia. The extent of anti-FSH antibody in the patients with azoospermia was significantly greater than that in patients with oligospermia and/or asthenospermia, infertile people with normal sperm density and motility and fertile people. The hypo-osmotic swelling test showed that the percentage of HOS-positive spermatozoa （swollen） was 45.1% ±3.5% in the FSH antibody-positive group and 59.1% ± 6.2% in the FSH antibody-negative control group. The percentage of functional membrane damage to spermatozoa was significantly higher in the anti- FSH antibody-positive group than in the control group. TEM showed that the outer acrosomal membrane was located far from the nucleus, and detachment of the acrosome was found in the FSH autoantibody-positive group. Conclusion： These data suggest that the presence of anti-FSH antibody is strongly correlated with the sperm quantity and quality in idiopathic male infertility. Anti-FSH antibody may be an important factor causing spermatogenic dysfunction and infertility.

Cloning and Transcriptional Activity of Follicle-Stimulating Hormone Receptor Promoter in the Jintang Black Goat

[ Objective] To clone follicle-stimulating hormone receptor （FSHR） promoter in the Jintang black goat, study its transcriptional activity, and provide a basis for alternative splicing of FSHR gene. [Method] The total DNA were extracted from the womb of Jintang black goat, and one pair of primers were designed for amplification of FSHR promoter fragments, then the sequences and homology were analyzed. The FSHR promoter fragment was inserted into the pcFSHRB1 expression vector to substitute the CMV promoter and construct the pcFSHRB2 expression vector. The pcFSHRB1 and pcFSHRB2 expression vectors were transformed into HEK293 cells, respectively. Then these cells were collected after 24 and 48 h treatment with 2 mlU/ml follicle-stimulating hormone （FSH）, and the cAMP levels were detected. [Result] The FSHR promoter sequence of Jin- tang black goat had 34.2% homology to that of chicken and 41.6% to that of rat, respectively. The transcription initial site of FSHR was at -576 bp and its upstream sequences contained two TATA-boxes, four CAAT-boxes, one E-box and one Wl-box. After treating for 24 and 48 h, the cAMP levels of pcFSHRB2 were respectively 299.581 3 and 125.528 1 pmol/L; and that of pcFSHRB1 were respectively 120.057 1 and 109.940 7 pmoVL. [Conclusion] The FSHR promoter of Jintang black goat is a typical type 2 eukaryotic promoter, and it is also a strong promoter.

Effects of Antisense Oligodeoxynucleotide to Follicle-stimulating Hormone Receptor on the Cell Proliferation and Apoptosis in Cells Derived from Human Ovarian Mucinous Cystadenocarcinoma in Vitro

The human ovarian mucinous cystadenocarcinoma （hOMC） cells were co-cultured with antisense oligodeoxynucleotide （antisense ODN）, nonsense ODN, and follicle-stimulating hormone （FSH） at different concentrations for the purpose of observing the effects of antisense ODN to FSH receptor （FSHR） on the proliferation and apoptosis of cultured hOMC cells in vitro. The inhibitory rates of growth were measured by using MTT method on the 2nd, 4th, 6th, 8th and 10th days after the interference of antisense ODN, nonsense ODN, and FSH, respectively. The apoptotic rates and the cell cycles were determined by means of flow cytometry, the apoptosis indexes were detected by using TUNEL, and the expression of caspase-3 was measured by using SP immunohistochemistry. Compared with that in the control group, the proliferative activity of hOMC cells was increased obviously in FSH groups （P〈0.05 or P〈0.01）, decreased distinctly in antisense ODN groups （P〈0.05 or P〈0.01）, and unchanged in nonsense ODN groups, respectively. Meanwhile, antisense ODN could significantly antagonize the FSH-promoted cell proliferative activity （P〈0.01）. Compared with those in the control group, the apoptotic rates and the expression of caspase-3 were dramatically increased in the mid- and high-dose antisense ODN groups （P〈0.05 or P〈0.01）, while the number of cells in G1/G0 phase was significantly decreased and that in S phase distinctly increased （P〈0.01）, There was no change in nonsense ODN groups （P〉0.05）, It was suggested that FSH may improve the development of hOMC cells, However, antisense ODN could inhibit proliferative activity and the FSH-promoted proliferative activity in hOMC cells, at the same time, antisense ODN could inhibit hOMC cell growth by inducing apoptosis.

Follicle-stimulating Hormone(FSH) Induced Internalization of Porcine FSH Receptor in Cultured Porcine Granulosa Cells and Chinese Hamster Ovary Cells Transfected with Recombinant Porcine FSH Receptor cDNA

In order to study the fate of human follicle-stimulating hormone (FSH) when hormone binds to its receptor, a quick biochemical method that can differentiate between the surface-bound and internalized hormone was used to determine the internalization induced by FSH in cultured both porcine granulosa cells and Chinese hamster ovary (CHO) cells expressing recombinant porcine FSH receptor. The results showed that FSH was slowly internalized, and the internalized radioactivity (acid resistant) reached a peak 10-12 h after addition of 125 I-hFSH. It was suggested that FSHR do not get internalized rapidly under physiological circumstances precisely because the appropriate sequences are absent.

Effect of Follicle-Stimulating Hormone Dosage, Seasons and Treatment Frequency on Super-Ovulation in Goats

[ Objective] To explore the effects of FSH （ Follicle-stimulating hormone）, seasons and treatment frequency on super-ovulation in donor goats and to provide necessary data for research about embryo transfer and embryo biotechnology in Yangzhou area. [ Method] Two FSH dosages （240 and 300 I U）, two seasons （April- June and October- December）, and two treatment frequencies （one or two times） were used to induce super-ovulation in goats. [ Result] Both average ovulation point and number of transferable embryos were significantly different between the goats given 240 IU FSH and those given 300 lU FSH （average ovulation point, 10.12 vs 15.55; number of transferable embryos, 8.82 vs 13.15） at the 0.05 level. Both average ovulation point and number of transferable embryos were also significantly different between April -June and October- December （ average ovulation point, 9.05 vs 15.55; number of transferable embryos, 7.05 vs 13.15） at the 0.05 level. Super-ovulation effect was not significantly different between the two treatment frequencies. [ Conduslonl The FSH dosages and seasons have significant impact on super-ovu- lation, but repeat super-ovulation does not have the same impact.

Polymorphism of Follicle-Stimulating Hormone Receptor Gene in Ningxia Tan Sheep

[ Objective] To study the polymorphism of follicle-stimulating hormone receptor （FSHR） gene in Ningxia Tan sheep and thus to provide a theoretical basis for breeding. I Methodl Genotypes of 111 healthy Ningxia Tan sheep were examined by polymerase chain reaction and restriction fragment length polymorphism （PCR-RFLP）. [ResultS] A 306-bp fragment was amplified. The PCR products digested with restriction enzyme Alu I showed polymorphism with three genotypes, L e., GG, CG and CC. The genotypic frequencies of GG, CG and CC were 0.135 1 （ 15 individuals）, 0.666 7 （74 individuals） and 0.198 2 （22 individuals）, respectively. The allele frequencies of G and C were 0.468 5 and 0.531 5, respectively.[ Conclusion] FSHR aene is Dolvmomhic in Ninaxia Tan Sheeo.

The Determination and Evaluation of the Biological Activities for the Commercialization of Recombinant Follicle-Stimulating Hormone in Vitro

Follicle-stimulating hormone (FSH) plays a central role in mammals reproduction, with the actions of FSH mediated by follicle-stimulating hormone receptors (FSHRs) on the surface of target cells. The purposes of this study were to determine and evaluate the biological activities for the commercialization of recombinant follicle-stimulating hormone (rFSH) in vitro through the cellular internalization using cloned 293T-FSHR cell lines as target. Using imaging approaches we have found here that a little fluorescent signal from the surface of the cell transferred to the cytoplasm and accumulated around the nucleus by endocytosis. Compared with the control groups, the commercialization of rFSH have not the significant differences of internalization, but the rFSH have promoted the internalization of the fluorescent, suggested that this detection system might as a protocol for the bioactivity of recombinant therapeutic proteins in vitro.

Role of follicle-stimulating hormone and estradiol benzoate in recovering spermatogenesis in tamoxifen-injured rats

Objective:To evaluate the effects of follicle-stimulating hormone (FSH) and estradiol benzoate (EB) on the recovery of spermatogenesis, histology, sexual hormones levels and testicular gene expression in testes of tamoxifen-injured rats.Methods:Forty adult rats were divided into eight groups in a factorial arrangement of tamoxifen and hormonal treatments. Half of the groups orally received 0.6 mg/kg tamoxifen, and 30 d later tamoxifen and no-tamoxifen groups (controls) were paired and assigned into four hormonal treatments with daily intramuscular injections for 10 consecutive days: 1 mL saline (control);7.5 IU FSH;12 μg/kg EB;and 7.5 IU FSH+12 μg/kg EB. One day after the last treatment, spermatozoa were recovered from epididymis, blood was processed for sex hormones concentration (testosterone, FSH and luteinizing hormone) and testes were processed for histology and RNA extraction for expression of genes related to apoptosis [caspase 3, inducible nitric oxide synthase (iNOS) and B-cell lymphoma-2 (Bcl-2)].Results: Control groups did not show significant changes in most parameters, but hormonal treatments decreased caspase 3 and iNOS and increased Bcl-2 expression. Tamoxifen significantly decreased counts, motility and viability of spermatozoa, Bcl-2 expression and sex hormones. It increased intertubular space, caspase 3 and iNOS expression, and induced seminiferous tubular atrophy. The hormonal treatments reverted spermatogenesis, hormonal levels and histology compared with controls, however not attaining the same sperm quality as controls.Conclusions:Tamoxifen is clearly detrimental to spermatogenesis and overall testicular structure and function, whereas hormonal therapy with FSH and EB can improve testicular function and revert tamoxifen-induced azoospermia.

Stability of Human Follicle-Stimulating Hormone Receptor mRNA in Stably Transfected Cells

In order to assess the impact of mRNA degradation on steady state levels of follicle stimulating hormone receptor (FSHR) mRNA and on regulation of FSHR gene expression, the stability and half life of FSHR mRNA were determined in transfected cells expressing recombinant FSHR. Time dependent changes in FSHR mRNA content were determined by nuclease protection solution hybridization assay (NPA) or by qualitative reverse transcription competitive polymerase chain reaction (RT PCR) in cultured hFSHR YI cells, cell lines stably transfected with a human FSHR cDNA. FSHR mRNA content remained constant during 8 h control incubations of hFSHR Y1 cells (NPA, 2.9±0.3 μg/mg RNA; RT PCR, 2.7±0.3 μg/mg RNA). Actinomycin D (ActD, 5 μg/ml) inhibited mRNA synthesis, as assessed by incorporation of uridine into total RNA, by 90 % within 1 h in hFSHR Y1 cells. No effect of ActD on cellular morphology or viability was observed. ActD caused a time dependent decrease in FSHR mRNA content in hFSHR Y1 cell lines with a lag time of 1 h. There were no significant differences in the rate of FSHR mRNA degradation between the two methods of mRNA quantification. The half life of hFSHR mRNA was 3.6±0.2 h by NPA and 3.1±0.1 h by RT PCR. The results indicated that degradation of mRNA was an important process in maintenance of steady state expression of the FSHR gene in cells stably expressing recombinant receptor.

Quantification of Porcine Follicle-stimulating Hormone Receptor Messenger Ribonucleic Acid by Reverse Transcription competitive Polymerase Chain Reaction

An easy and reliable method was developed for construction and quantification of competitive templates, which shared the same sequence as the amplified target DNA except for a 20 bp insertion in the middle by recombinant polymerase chain reaction (PCR). Among the advantages of competitive PCR is that any predictable or unpredictable variable that affects amplification has the same effect on both target and competitor species and that the final ratio of amplified products reflects exactly the initial targets. The utilization of a thermostable reverse transcriptase in the RT step was proposed to overcome the problem of the efficiency of target cDNA synthesis. In addition, to obtain reliable measurements, it was recommended to perform four PCR with amounts of competitive template flanking the concentration of the target mRNA.

Hepatoprotective effects of Xiaoyao San formula on hepatic steatosis and inflammation via regulating the sex hormones metabolism

BACKGROUND The modified Xiaoyao San(MXS)formula is an adjuvant drug recommended by the National Health Commission of China for the treatment of liver cancer,which has the effect of preventing postoperative recurrence and metastasis of hepatocellular carcinoma and prolonging patient survival.However,the molecular mechanisms underlying that remain unclear.AIM To investigate the role and mechanisms of MXS in ameliorating hepatic injury,steatosis and inflammation.METHODS A choline-deficient/high-fat diet-induced rat nonalcoholic steatohepatitis(NASH)model was used to examine the effects of MXS on lipid accumulation in primary hepatocytes.Liver tissues were collected for western blotting and immunohisto chemistry(IHC)assays.Lipid accumulation and hepatic fibrosis were detected using oil red staining and Sirius red staining.The serum samples were collected for biochemical assays and NMR-based metabonomics analysis.The inflammation/lipid metabolism-related signaling and regulators in liver tissues were also detected to reveal the molecular mechanisms of MXS against NASH.RESULTS MXS showed a significant decrease in lipid accumulation and inflammatory response in hepatocytes under metabolic stress.The western blotting and IHC results indicated that MXS activated AMPK pathway but inhibited the expression of key regulators related to lipid accumulation,inflammation and hepatic fibrosis in the pathogenesis of NASH.The metabonomics analysis systemically indicated that the arachidonic acid metabolism and steroid hormone synthesis are the two main target metabolic pathways for MXS to ameliorate liver inflammation and hepatic steatosis.Mechanistically,we found that MXS protected against NASH by attenuating the sex hormone-related metabolism,especially the metabolism of male hormones.CONCLUSION MXS ameliorates inflammation and hepatic steatosis of NASH by inhibiting the metabolism of male hormones.Targeting male hormone related metabolic pathways may be the potential therapeutic approach for NASH.

Effects of hormone replacement therapy on mood and sleep quality in menopausal women

BACKGROUND Hormone replacement therapy is an effective treatment strategy for the management of symptoms in naturally menopausal women.However,some patients report experiencing adverse effects.AIM To analyze the effects of hormone replacement therapy in menopausal female patients.METHODS A total of 152 menopausal female patients admitted to the Gynecology Department of the Ganzhou Maternal and Child Health Hospital between January 2021 and December 2023 were divided into the observation group(n=76,conventional treatment+hormone replacement therapy)and the control group(n=76,conventional treatment only)via random casting.The improvement observed in the following items were compared between the groups:Kupperman menopausal index(KMI),emotional state[The Positive and Negative Affect Scale(PANAS)],sleep quality[Self-Rating Scale of Sleep(SRSS)],treatment effectiveness,and treatment safety.RESULTS The modified KMI and SRSS scores of the observation group were lower than those of the control group after three rounds of treatment.The improvement in the PANAS score observed in the observation group was greater than that observed in the control group(P<0.05).The total treatment effectivity rate in the observation group was higher than that in the control group(86.84%vs 96.05%,χ2=4.121,P=0.042).The incidence rate of adverse reactions in the two groups was comparable(6.58%vs 9.21%,χ2=0.361,P=0.547).CONCLUSION Hormone replacement therapy effectively improved the clinical symptoms,actively channeled negative emotions,and improved the quality of sleep in menopausal patients,indicating its effectiveness and safety.

Unraveling the gut-brain axis:the impact of steroid hormones and nutrition on Parkinson's disease

This comprehensive review explores the intricate relationship between nutrition,the gut microbiome,steroid hormones,and Parkinson's disease within the context of the gut-brain axis.The gut-brain axis plays a pivotal role in neurodegenerative diseases like Parkinson's disease,encompassing diverse components such as the gut microbiota,immune system,metabolism,and neural pathways.The gut microbiome,profoundly influenced by dietary factors,emerges as a key player.Nutrition during the first 1000 days of life shapes the gut microbiota composition,influencing immune responses and impacting both child development and adult health.High-fat,high-sugar diets can disrupt this delicate balance,contributing to inflammation and immune dysfunction.Exploring nutritional strategies,the Mediterranean diet's anti-inflammatory and antioxidant properties show promise in reducing Parkinson's disease risk.Microbiome-targeted dietary approaches and the ketogenic diet hold the potential in improving brain disorders.Beyond nutrition,emerging research uncovers potential interactions between steroid hormones,nutrition,and Parkinson's disease.Progesterone,with its anti-inflammatory properties and presence in the nervous system,offers a novel option for Parkinson's disease therapy.Its ability to enhance neuroprotection within the enteric nervous system presents exciting prospects.The review addresses the hypothesis thatα-synuclein aggregates originate from the gut and may enter the brain via the vagus nerve.Gastrointestinal symptoms preceding motor symptoms support this hypothesis.Dysfunctional gut-brain signaling during gut dysbiosis contributes to inflammation and neurotransmitter imbalances,emphasizing the potential of microbiota-based interventions.In summary,this review uncovers the complex web of interactions between nutrition,the gut microbiome,steroid hormones,and Parkinson's disease within the gut-brain axis framework.Understanding these connections not only offers novel therapeutic insights but also illuminates the origins of neurodegenerative diseases such as Parkinson's disease.

Adipokinetic hormone signaling regulates adult dehydration resistance in the migratory locust

Drought events have become more severe under climate change,and this can pose a major threat to the survival of various organisms.The molecular mechanisms involved in dehydration resistance are not well known.Here,adults of the migratory locust,Locusta migratoria,were subjected to food-mediated dehydration,and adipokinetic hormone(AKH)signaling was found to play a key role in regulating dehydration resistance.Specifically,dehydration shortened the lifespan,increased the body weight loss,and reduced the water loss rate in adult locusts.Global transcriptome profiles revealed variations in tissue-specific gene expression between dehydration-resistant locusts and normal locusts.Importantly,dehydration selection and exposure induced prominent expression of AKH genes in the retrocerebral complex of adult locusts.Furthermore,individual knockdown of AKH1,AKH2,or AKH receptor(AKHR)accelerated water loss and shortened the lifespan of adult locusts under dehydration conditions,and trehalose supplementation ameliorated the negative effects caused by interference with AKH or AKHR.These findings demonstrated that AKH/AKHR signaling-dependent trehalose metabolism plays a crucial role in regulating locust dehydration resistance and thus provide novel insights into the regulatory mechanism underlying drought resistance.

Role of bisphosphonates in osteoporosis caused by adult growth hormone deficiency

In recent years,growth hormone and insulin-like growth factors have become key regulators of bone metabolism and remodeling,crucial for maintaining healthy bone mass throughout life.Studies have shown that adult growth hormone deficiency leads to alterations in bone remodeling,significantly affecting bone microarchitecture and increasing fracture risk.Although recombinant human growth hormone replacement therapy can mitigate these adverse effects,improving bone density,and reduce fracture risk,its effectiveness in treating osteoporosis,especially in adults with established growth hormone deficiency,seems limited.Bisphosphonates inhibit bone resorption by targeting farnesyl pyrophosphate synthase in osteoclasts,and clinical trials have confirmed their efficacy in improving osteoporosis.Therefore,for adult growth hormone deficiency patients with osteoporosis,the use of bisphosphonates alongside growth hormone replacement therapy is recommended.

Vitamin D, Parathyroid Hormone, Insulin Sensitivity and Islet β-Cell Secretory Function in Diabetic Patients from South Kivu in the Democratic Republic of Congo: Cross-Sectional Study

Background: The role of vitamin D and parathyroid hormone in the metabolic profile of type 2 diabetes mellitus in sub-Saharan Africa has not been adequately assessed. The aim of this study was to determine the prevalence of low vitamin D level and secondary hyperparathyroidism and their association with insulin sensitivity and β-cell secretory function among Congolese type 2 diabetics. Methodology: Fasting glycaemia, fasting insulin, 25OH D3 and human parathyroid hormone (hPTH) were measured in one hundred and eighty-four type 2 diabetic patients followed as outpatients in South Kivu. Levels of 25OH D3 65 pg/ml defined low vitamin D and elevated parathyroid hormone levels, respectively. The HOMA model was used to measure insulin sensitivity and β-cell secretory function. Results: Medians (IQR) were 25.3 (20.4 - 32.4) ng/ml for 25OH D3 and 53.7 (38.4 - 115.7) pg/ml for hPTH. 58.7% of diabetics had insulin resistance, 126 (68.5%) had low vitamin D and 80 (43.5%) had hyperparathyroidism. In multivariate analysis, hPTH (partial r = −0.28;p = 0.0002) and 25OH D3 (partial r = 0.16;p = 0.03) showed an independent association with insulin sensitivity after adjustment for body mass index and waist circumference. Finally, hPTH (partial r = 0.27;p = 0.0002) was the sole determinant of β-cell secretory function. Conclusions: This study confirms the high prevalence of low vitamin D level and secondary hyperparathyroidism and their association with insulin resistance and impaired islet β-cell secretory function among Congolese with type 2 diabetes mellitus. Vitamin D and calcium supplementation should be envisaged for cases of deficiency in this region.

Simultaneous determination of five plant hormones in cotton leaves using QuEChERS combined with HPLC‒MS/MS

Background Plant hormones profoundly influence cotton growth,development,and responses to various stresses.Therefore,there is a pressing need for an efficient assay to quantify these hormones in cotton.In this groundbreaking study,we have established QuEChERS-HPLC‒MS/MS method,for the simultaneous detection of multiple plant hormones in cotton leaves,allowing the analysis and quantification of five key plant hormones.Results Sample extraction and purification employed 0.1%acetic acid in methanol and C18 for optimal recovery of plant hormones.The method applied to cotton demonstrated excellent linearity across a concentration range of 0.05–1 mg・L−1,with linear regression coefficients exceeding 0.99.The limits of quantification(LOQs)were 20μg・kg−1 for GA3 and 5μg・kg−1 for the other four plant hormones.Recovery rates for the five plant hormones matrix spiked at levels of 5,10,100,and 1000μg・kg−1 were in the range of 79.07%to 98.97%,with intraday relative standard deviations(RSDs)ranging from 2.11%to 8.47%.The method was successfully employed to analyze and quantify the five analytes in cotton leaves treated with plant growth regulators.Conclusion The study demonstrates that the method is well-suited for the determination of five plant hormones in cotton.It exhibits excellent selectivity and sensitivity in detecting field samples,thus serving as a robust tool for indepth research into cotton physiology.

Research status of hormone replacement therapy on mood and sleep quality in menopausal women

Menopausal syndrome is a common disease of clinical women,which refers to a series of physical and mental symptoms caused by the fluctuation or reduction of sex hormones before and after menopause.Many of these patients have sleep and mood abnormalities that affect their health and quality of life.At present,the understanding of it is gradually improving.This paper mainly analyzes its back-ground and current treatment.

Gut microbiota affects the estrus return of sows by regulating the metabolism of sex steroid hormones

Background Sex hormones play important roles in the estrus return of post-weaning sows.Previous studies have demonstrated a complex and bi-directional regulation between sex hormones and gut microbiota.However,the extent to which the gut microbiota affects estrus return of post-weaning sows is largely unknown.Results In this study,we first screened 207 fecal samples from well-phenotyped sows by 16S rRNA gene sequencing and identified significant associations between microbes and estrus return of post-weaning sows.Using metagenomic sequencing data from 85 fecal samples,we identified 37 bacterial species that were significantly associated with estrus return.Normally returning sows were characterized by increased abundances of L.reuteri and P.copri and decreased abundances of B.fragilis,S.suis,and B.pseudolongum.The changes in gut microbial composition significantly altered the functional capacity of steroid hormone biosynthesis in the gut microbiome.The results were confirmed in a validation cohort.Significant changes in sex steroid hormones and related compounds were found between normal and non-return sows via metabolome analysis.An integrated analysis of differential bacterial species,metagenome,and fecal metabolome provided evidence that normal return-associated bacterial species L.reuteri and Prevotella spp.participated in the degradation of pregnenolone,progesterone,and testosterone,thereby promoting estrogen biosynthesis.Furthermore,the microbial metabolites related to sow energy and nutrient supply or metabolic disorders also showed relationships with sow estrus return.Conclusions An integrated analysis of differentially abundant bacterial species,metagenome,and fecal metabolome revealed the involvement of L.reuteri and Prevotella spp.in sow estrus return.These findings provide deep insight into the role of gut microbiota in the estrus return of post-weaning sows and the complex cross-talk between gut microbiota and sex hormones,suggesting that the manipulation of the gut microbiota could be an effective strategy to improve sow estrus return after weaning.