Probiotic Escherichia coli Nissle 1917-derived outer membrane vesicles modulate the intestinal microbiome and host gut-liver metabolome in obese and diabetic mice.

Introduction: Obesity and diabetes are common chronic metabolic disorders which can cause an imbalance of the intestinal flora and gut-liver metabolism. Several studies have shown that probiotics, including Escherichia coli Nissle 1917 (EcN), promote microbial balance and metabolic health. However, there are no studies on how EcN outer membrane vesicles (EcN-OMVs) influence the intestinal microflora and affect the metabolic disorders of obesity and diabetes. Methods: In this study, we evaluated the effects of EcN-OMVs on high-fat diet (HFD)-induced obesity and HFD + streptozotocin (STZ)-induced diabetes. Results: EcN-OMVs could reduce body weight, decrease blood glucose, and increase plasma insulin in obese mice. Similarly, EcN-OMVs treatment could modify the ratio of Firmicutes/Bacteroidetes in the gut, elevate intestinal short-chain fatty acid (SCFA)-producing flora, and influence the SCFA content of the intestine. Furthermore, the intestinal metabolites ornithine and fumaric acid, hepatic ω-6 unsaturated fatty acids, and SCFAs were significantly increased after administering EcN-OMVs. Discussion: Overall, this study showed that EcN-OMVs might act as post-biotic agents that could modulate gut-liver metabolism and ameliorate the pathophysiology of obesity and diabetes.

Sperm induce proinflammatory responses in the uterus and peripheral blood immune cells of artificially inseminated cows.

This in vivo study aimed to investigate local and systemic immune responses induced by sperm in cows after artificial insemination (AI). Initially, 12 multiparous Japanese Black cows were subjected to intrauterine AI (AI group, n = 6) or saline infusion (control group, n = 6). The uterine body and horn ipsilateral to the ovulatory follicle were mini-flushed with 2 ml of RPMI-1640 medium at different time points (0, 1, 6, 10, 24, 48 h, and 7 days after AI), centrifuged, and the sediments were examined under a light microscope. Vaginal smears were prepared at 0, 1, 6, and 10 h after AI to investigate the sperm backflow. Subsequently, another experiment was conducted by assigning cows to three groups: intrauterine AI (AI group, n = 5), heat-inactivated AI (Heat-AI group, n = 5), or saline infusion (control group, n = 5). Blood samples were collected, and polymorphonuclear neutrophils (PMNs) and peripheral blood mononuclear cells (PBMCs) were separated and analyzed for gene expression using real-time PCR. The results showed that most sperm were rapidly transported either forward into the uterine horn or backward into the vagina within 1 h after AI. The PMNs migrated into the uterine lumen 6 hours after AI. Only active sperm-induced proinflammatory responses in PMNs and PBMCs via upregulation of TNFa, IL8, IL1B, and PGES and downregulation of IL10 at 6 h after AI. These data provide evidence that sperm generate transient proinflammatory responses locally in the uterus and systemically in the peripheral immune cells, which may be prerequisites for uterine clearance, embryo receptivity, and implantation in cows.

The complex metabolic interactions of liver tissue and hepatic exosome in PCOS mice at young and middle age.

Polycystic ovary syndrome (PCOS) is a common age-related endocrinopathy that promotes the metabolic disorder of the liver. Growing evidence suggests that the pathophysiology of this disorder is closely associated with the interaction between the liver and its exosome. However, the underlying mechanism of the interactions remains unclear. In this study, we aimed to investigate the metabolite profiles of liver tissues and hepatic exosomes between normal (n = 11) and PCOS (n = 13) mice of young- and middle-age using gas chromatograph-mass spectrometry (GC-MS) based metabolomics analysis. Within the 145 identified metabolites, 7 and 48 metabolites were statistically different (p < 0.05, q < 0.05) in the liver tissue and exosomes, respectively, between PCOS and normal groups. The greater disparity in exosome indicated its potential to reflect the metabolic status of the liver. Based on hepatic exosome metabolome, the downregulations of glycolysis and TCA cycle were related to hepatic pathophysiology of PCOS independent of age. Fatty acids were the preferred substrates in young-age-PCOS liver while amino acids were the main substrates in middle-age-PCOS liver for the processes of gluconeogenesis. Overall, this study enables us to better understand the metabolic status of the PCOS liver at different ages, and exosome metabolomics shows its potential to gain the metabolic insights of parental cell or source organ.

Toll-like Receptor 2 is Involved in Calcium Influx and Acrosome Reaction to Facilitate Sperm Penetration to Oocytes During in vitro Fertilization in Cattle.

Cumulus cells of ovulated cumulus-oocyte complexes (COCs) express Toll-like receptor 2 (TLR2), pathogen recognition receptors, to recognize and react to sperm signals during fertilization. Sperm also express TLR2, but its contribution to the sperm-oocytes crosstalk is still unclear. Here, we adapted the in vitro fertilization (IVF) model to characterize the potential relevance of sperm TLR2 in sperm-oocytes interactions during fertilization in bovine. The IVF results showed that the ligation of sperm TLR2 with its specific antagonist/agonist resulted in down/up-regulation of the cleavage and blastocyst rates either in COCs or cumulus-free oocytes, but not in zona pellucida (ZP)-free oocytes. The computer-assisted sperm analysis (CASA) system revealed that sperm motility parameters were not affected in TLR2 antagonist/agonist-treated sperm. However, fluorescence imaging of sperm-ZP interactions revealed that the blockage or activation of the TLR2 system in sperm reduced or enhanced both binding and penetration abilities of sperm to ZP compared to control, respectively. Flow cytometrical analysis of acrosome reaction (AR) demonstrated that the TLR2 system adjusted the occurrence of AR in ZP-attached sperm, suggesting that sperm TLR2 plays physiological impacts on the sperm-oocyte crosstalk via regulating ZP-triggered AR in sperm. Given that calcium (Ca2+) influx is a pre-requisite step for the induction of AR, we investigated the impact of the TLR2 system on the ionophore A23187-induced Ca2+ influx into sperm. Notably, the exposure of sperm to TLR2 antagonist/agonist reduced/increased the intracellular Ca2+ level in sperm. Together, these findings shed new light that the TLR2 system is involved in sperm AR induction which enables sperm to penetrate and fertilize oocytes during the fertilization, at least in vitro, in cows. This suggests that sperm possibly developed a quite flexible sensing mechanism simultaneously against pathogens as well as COCs toward fertilization with the same TLR2 of the innate immune system.

[Effect of active component compound of Epimedii Folium,Astragali Radix,and Puerariae Lobatae Radix on expression of ADAM17 in HT22 cells by mediating hepcidin].

Alzheimer's disease(AD) patients in China have been surging, and the resultant medical burden and care demand have a huge impact on the development of individuals, families, and the society. The active component compound of Epimedii Folium, Astragali Radix, and Puerariae Lobatae Radix(YHG) can regulate the expression of iron metabolism-related proteins to inhibit brain iron overload and relieve hypofunction of central nervous system in AD patients. Hepcidin is an important target regulating iron metabolism. This study investigated the effect of YHG on the expression of a disintegrin and metalloprotease-17(ADAM17), a key enzyme in the hydrolysis of ß amyloid precursor protein(APP) in HT22 cells, by mediating hepcidin. To be specific, HT22 cells were cultured in vitro, followed by liposome-mediated siRNA transfection to silence the expression of hepcidin. Real-time PCR and Western blot were performed to examine the silencing result and the effect of YHG on hepcidin in AD cell model. HT22 cells were randomized into 7 groups: control group, Aß25-35 induction(Aß) group, hepcidin-siRNA(siRNA) group, Aß25-35 + hepcidin-siRNA(Aß + siRNA) group, Aß25-35+YHG(Aß+YHG) group, hepcidin-siRNA+YHG(siRNA+YHG) group, Aß25-35+hepcidin-siRNA+YHG(Aß+siRNA+YHG) group. The expression of ADAM17 mRNA in cells was detected by real-time PCR, and the expression of ADAM17 protein by immunofluorescence and Western blot. Immunofluorescence showed that the ADAM17 protein expression was lower in the Aß group, siRNA group, and Aß+siRNA group than in the control group(P<0.05) and the expression was lower in the Aß+siRNA group(P<0.05) and higher in the Aß+YHG group(P<0.05) than in the Aß group. Moreover, the ADAM17 protein expression was lower in the Aß+siRNA group(P<0.05) and higher in the siRNA+YHG group(P< 0.05) than in the siRNA group. The expression was higher in the Aß+siRNA+YHG group than in the Aß+siRNA group(P<0.05). The results of Western blot and real-time PCR were consistent with those of immunofluorescence. The experiment showed that YHG induced hepcidin to up-regulate the expression of ADAM17 in AD cell model and promote the activation of non-starch metabolic pathways, which might be the internal mechanism of YHG in preventing and treating AD.

Transcriptome profile of goat folliculogenesis reveals the interaction of oocyte and granulosa cell in correlation with different fertility population.

To understand the molecular and genetic mechanisms related to the litter size in one species of two different populations (high litter size and low litter size), we performed RNA-seq for the oocytes and granulosa cells (GCs) at different developmental stages of follicle, and identified the interaction of genes from both sides of follicle (oocyte and GCs) and the ligand-receptor pairs from these two sides. Our data were very comprehensive to uncover the difference between these two populations regarding the folliculogenesis. First, we identified a set of potential genes in oocyte and GCs as the marker genes which can be used to determine the goat fertility capability and ovarian reserve ability. The data showed that GRHPR, GPR84, CYB5A and ERAL1 were highly expressed in oocyte while JUNB, SCN2A, MEGE8, ZEB2, EGR1and PRRC2A were highly expressed in GCs. We found more functional genes were expressed in oocytes and GCs in high fertility group (HL) than that in low fertility group (LL). We uncovered that ligand-receptor pairs in Notch signaling pathway and transforming growth factor-ß (TGF-ß) superfamily pathways played important roles in goat folliculogenesis for the different fertility population. Moreover, we discovered that the correlations of the gene expression in oocytes and GCs at different stages in the two populations HL and LL were different, too. All the data reflected the gene expression landscape in oocytes and GCs which was correlated well with the fertility capability.

Neutrophils recognize and amplify IFNT signals derived from day 7 bovine embryo for stimulation of ISGs expression in vitro: A possible implication for the early maternal recognition of pregnancy.

Previously, we reported that the presence of multiple day 7 (D7) bovine embryos in the uterus induces systemic immune responses in circulating polymorphonuclear neutrophils (PMNs), but with unknown mechanism. Thus, this study aimed to investigate the direct impact of D7 bovine embryo on PMNs' immune responses in vitro and whether these PMNs can amplify and transfer embryo signals further to another PMN population. PMNs were directly stimulated by embryo culture media (ECM) or interferon tau (IFNT) (10 ng/ml) followed by evaluating mRNA expression by real-time PCR and phenotypic analysis by flow cytometry. To test whether PMNs can transfer embryo signals to a new PMN population, PMNs triggered by ECM or IFNT, were thoroughly washed and diluted to remove any media components, and again were incubated in fresh culture media for 3 h, from which culture supernatants were collected and used as PMN conditioned media (CM) to stimulate a new PMN population. Similar to ECM, IFNT directly stimulated expressions of IFNs (IFNA, IFNG), interferon-stimulated genes (ISGs; OAS1, ISG15, MX1), STAT1, TGFB and IL8, and downregulated TNFA in PMNs. Flow cytometrical analyses demonstrated that IFNT stimulated expressions of pregnancy-related phenotypic markers, CD16 and arginase-1 (ARG1), in PMNs. Most importantly, PMN CM induced ISGs and STAT1 mRNA in fresh PMNs. Since IFNT directly upregulated IFNA expression in PMNs, the impact of IFNA on PMNs' immune responses was further tested. Stimulation of PMNs with IFNA, especially at a low level (1 pg/ml), induced IFNT-like immune responses comparable to those induced by PMN CM. Together, these findings indicated that D7 bovine embryos induce direct anti-inflammatory responses with upregulation of ISGs expressions in PMNs mainly via IFNT. Additionally, PMNs can amplify and transfer embryo signals to a new PMN population in a cell-to-cell communication mechanism possibly mediated in part by IFNA. Such a novel immunological crosstalk might contribute to embryo tolerance and pregnancy establishment in cattle.

ß-carotene Rescues Busulfan Disrupted Spermatogenesis Through Elevation in Testicular Antioxidant Capability.

ß-carotene, precursor of vitamin A, is an excellent antioxidant with many beneficial properties. It is a lipid-soluble antioxidant and a very effective quencher of reactive oxygen species (ROS) to reduce the oxidative stress. In contrast to vitamin A, ß-carotene is not toxic even consumed in higher amount when it is delivered from natural plant products. Recently, we found that ß-carotene acts as a potential antioxidant in the oocyte to improve its quality. Even though many studies have been reported that ß-carotene has the beneficial contribution to the ovarian development and steroidogenesis, it is unknown the effects of ß-carotene on the spermatogenesis. This investigation aimed to explore the hypothesis that ß-carotene could improve spermatogenesis and the underlying mechanism. And we found that ß-carotene rescued busulfan disrupted spermatogenesis in mouse with the increase in the sperm concentration and motility. ß-carotene improved the expression of genes/proteins important for spermatogenesis, such as VASA, DAZL, SYCP3, PGK2. Moreover, ß-carotene elevated the testicular antioxidant capability by the elevation of the antioxidant glutathione and antioxidant enzymes SOD, GPX1, catalase levels. In conclusion, ß-carotene may be applied for the infertile couples by the improvement of spermatogenesis, since, worldly many couples are infertile due to the idiopathic failed gametogenesis (spermatogenesis).

scRNA-seq of ovarian follicle granulosa cells from different fertility goats reveals distinct expression patterns.

The new technology of high-throughput single-cell RNA sequencing (10 × scRNA-seq) was developed recently with many advantages. However, it was not commonly used in farm animal research. There are few reports for the gene expression of goat ovarian follicle granulosa cells (GCs) during different developmental stages. In the current investigation, the gene expression of follicle GCs at different stages from two populations of Ji'ning grey goats: high litter size (HL; ≥3/L; 2 L) and low litter size (LL; ≤2 /L; 2 L) were analysed by scRNA-seq. Many GC marker genes were identified, and the pseudo-time showed that GCs developed during the time course which reflected the follicular development and differentiation trajectory. Moreover, the gene expression difference between the two populations HL versus LL was very clear at different developmental stages. Many marker genes differentially expressed at different developmental stages. ASIP and ASPN were found to be highly expressed in the early stage of GCs, INHA, INHBA, MFGE8 and HSD17B1 were identified to be highly expressed in the growing stage of GCs, while IGFBP2, IGFBP5 and CYP11A1 were found to be highly expressed in late stage. These marker genes could be used as reference genes of goat follicle GC development. This investigation for the first time discovered the gene expression patterns in goat follicle GCs in high- or low-fertility populations (based on litter size) by scRNA-seq which may be useful for uncovering the oocyte development potential.

Fabrication of hollow flower-like magnetic Fe3O4/C/MnO2/C3N4 composite with enhanced photocatalytic activity.

The serious problems of environmental pollution and energy shortage have pushed the green economy photocatalysis technology to the forefront of research. Therefore, the development of an efficient and environmentally friendly photocatalyst has become a hotpot. In this work, magnetic Fe3O4/C/MnO2/C3N4 composite as photocatalyst was synthesized by combining in situ coating with low-temperature reassembling of CN precursors. Morphology and structure characterization showed that the composite photocatalyst has a hollow core-shell flower-like structure. In the composite, the magnetic Fe3O4 core was convenient for magnetic separation and recovery. The introduction of conductive C layer could avoid recombining photo-generated electrons and holes effectively. Ultra-thin g-C3N4 layer could fully contact with coupled semiconductor. A Z-type heterojunction between g-C3N4 and flower-like MnO2 was constructed to improve photocatalytic performance. Under the simulated visible light, 15 wt% photocatalyst exhibited 94.11% degradation efficiency in 140 min for degrading methyl orange and good recyclability in the cycle experiment.

Peptidoglycan disrupts early embryo-maternal crosstalk via suppression of ISGs expression induced by interferon-tau in the bovine endometrium.

Uterine infection with bacteria and the release of peptidoglycan (PGN), antigenic cell wall components of both Gram-negative and Gram-positive bacteria, can cause early pregnancy losses in ruminants, but the associated mechanisms remain unsolved. Day 7 blastocyst starts to secrete a minute amount of interferon-tau (IFNT) in the uterine horn which is required for early stage of maternal recognition of pregnancy (MRP) in ruminants, and it induces interferon stimulated genes (ISGs) for driving uterine receptivity in cows. This study investigated if PGN disrupts IFNT response through modulation of endometrial ISGs expressions. Cultured bovine endometrial epithelial cells (BEECs) were treated with embryo culture medium (ECM) or IFNT (1 ng/ml) in the presence or absence of a low level of PGN (10 pg/ml) for 24 h. A real-time PCR analyses revealed that the presence of PGN suppressed IFNT-induced ISGs (OAS1 and ISG15) and STAT1 expressions in BEECs. To visualize the impact of PGN in an ex-vivo model that resembles the in vivo status, endometrial explants were treated by IFNT (1 ng/ml) with or without PGN (10 pg/ml) for 12 h. PGN suppressed IFNT-induced gene expressions of the above factors, but not for IFNA receptor type1 (IFNAR1) or type2 (IFNAR2) in explants. Immunofluorescence analysis illustrated that PGN completely suppressed the IFNT-triggered OAS1 protein expression in the luminal epithelium of explants. Of note, PGN did not stimulate pro-inflammatory cytokines (TNFA and IL1B) or TLR2 mRNA expression in both models. These findings indicate that the presence of low levels of PGN suppresses ISGs expression induced by IFNT secreted from early embryo, at the luminal epithelium of the bovine endometrium. This could severely interfere with early stage of MRP processes in cows, leading to pregnancy failure.

Chlorothalonil inhibits mouse ovarian development through endocrine disruption.

Although many studies have investigated the toxic effects and even the reproductive toxicity of chlorothalonil, almost no studies have focused on the ovary, the organ of oocyte development. Puberty is a critical window for development of the female reproductive system. Therefore, this investigation aimed to explore the effects and underlying mechanisms of chlorothalonil at low doses on peripubertal mouse ovarian development. Chlorothalonil is frequently used in horticulture with short intervals between applications, therefore, vegetables and fruits may be potential sources of chlorothalonil contamination. For the first time, this study demonstrated that chlorothalonil inhibited ovarian development during puberty in mice, and at levels currently assumed to have no adverse health consequences for humans. Chlorothalonil exposure inhibited mouse ovarian development by increasing the number of primary follicles and decreasing the number of mature follicles. It acted by decreasing the levels of hormone production proteins, such as FSH receptor and estrogen receptor alpha, while increasing the levels of DNA repairing marker RAD51 and cell apoptosis. These results suggest that chlorothalonil may disrupt endocrine function and inhibit murine ovarian development. Therefore it may pose a potential health risk to female reproductive systems in other species, especially to the ovary.

METTL3-mediated N6-methyladenosine mRNA modification enhances long-term memory consolidation.

The formation of long-term memory is critical for learning ability and social behaviors of humans and animals, yet its underlying mechanisms are largely unknown. We found that the efficacy of hippocampus-dependent memory consolidation is regulated by METTL3, an RNA N6-methyladenosine (m6A) methyltransferase, through promoting the translation of neuronal early-response genes. Such effect is exquisitely dependent on the m6A methyltransferase function of METTL3. Depleting METTL3 in mouse hippocampus reduces memory consolidation ability, yet unimpaired learning outcomes can be achieved if adequate training was given or the m6A methyltransferase function of METTL3 was restored. The abundance of METTL3 in wild-type mouse hippocampus is positively correlated with learning efficacy, and overexpression of METTL3 significantly enhances long-term memory consolidation. These findings uncover a direct role of RNA m6A modification in regulating long-term memory formation, and also indicate that memory efficacy difference among individuals could be compensated by repeated learning.

Zinc Oxide Nanoparticle Caused Plasma Metabolomic Perturbations Correlate with Hepatic Steatosis.

Zinc oxide nanoparticles (ZnO NPs), known for their chemical stability and strong adsorption, are used in everyday items such as cosmetics, sunscreens, and prophylactic drugs. However, they have also been found to adversely affect organisms; previously we found that ZnO NPs disrupt pubertal ovarian development, inhibit embryonic development by upsetting γ-H2AX and NF-κB pathways, and even disturb skin stem cells. Non-targeted metabolomic analysis of biological organisms has been suggested as an unbiased tool for the investigation of perturbations in response to NPs and their underlying mechanisms. Although metabolomics has been used in nanotoxicological studies, very few reports have used it to investigate the effects of ZnO NPs exposure. In the current investigation, through a metabolomics-based approach, we discovered that ZnO NPs caused changes in plasma metabolites involved in anti-oxidative mechanisms, energy metabolism, and lipid metabolism in hen livers. These results are in line with earlier findings that ZnO NPs perturb the tricarboxylic acid cycle and in turn result in the use of alternative energy sources. We also found that ZnO NPs disturbed lipid metabolism in the liver and consequently impacted blood lipid balance. Changes in plasma metabolomes were correlated with hepatic steatosis.

MicroRNA-221 may be involved in lipid metabolism in mammary epithelial cells.

Milk lipids, important for infant growth and development, are produced and secreted by mammary gland under the regulation of steroid hormones, growth factors, and microRNAs (miRNAs). miR-221 has been identified in milk and adipocytes and it plays important roles in regulating normal mammary epithelial hierarchy and breast cancer stem cells; however, its roles in lipid metabolism in mammary epithelial cells (MECs), the cells of lipid synthesis and secretion, are as yet unknown. Through overexpression or inhibition of miR-221 expression, we found that it regulated lipid metabolism in MECs and was expressed differentially at various stages during murine mammary gland development. Inhibition of miR-221 expression increased lipid content in MECs through elevation of the lipid synthesis enzyme FASN, while overexpression of miR-221 reduced MEC lipid content. Moreover, the steroid hormones estradiol and progesterone decreased miR-221 expression with a subsequent increase in lipid formation in MECs. The expression of miR-221 was lower during lactation, which suggests that it may be involved in milk production. Therefore, miR-221 might be a useful target for influencing milk lipid production.

miR-15b negatively correlates with lipid metabolism in mammary epithelial cells.

Mammary epithelial cells are regulated by steroid hormones, growth factors, and even microRNAs. miR-15b has been found to regulate lipid metabolism in adipocytes; however, its effects on lipid metabolism in mammary epithelial cells, the cells of lipid synthesis and secretion, are as yet unknown. The main purpose of this investigation was to explore the effect of miR-15b on lipid metabolism in mammary epithelial cells, along with the underlying mechanisms. miR-15b was overexpressed or inhibited by miRNA mimics or inhibitors; subsequently, lipid formation in mammary epithelial cells, and proteins related to lipid metabolism, were investigated. Through overexpression or inhibition of miR-15b expression, the current investigation found that miR-15b downregulates lipid metabolism in mammary epithelial cells and is expressed differentially at various stages of mouse and goat mammary gland development. Inhibition of miR-15b expression increased lipid content in mammary epithelial cells through elevation of the lipid synthesis enzyme fatty acid synthetase (FASN), and overexpression of miR-15b reduced lipid content in mammary epithelial cells with decreasing levels of FASN. Moreover, the steroid hormones estradiol and progesterone decreased miR-15b expression with a subsequent increase in lipid formation in mammary epithelial cells. The expression of miR-15b was lower during lactation and negatively correlated with lipid synthesis proteins, which suggests that it may be involved in lipid synthesis and milk production. miR-15b might be a useful target for altering lipid production and milk yield.

Decrease in male mouse fertility by hydrogen sulfide and/or ammonia can Be inheritable.

Numerous epidemiological studies suggest that air pollutants cause a decline in the quality of human spermatozoa and thus a reduction in fertility. However, the exact cause of infertility remains unknown. Air pollution gases, such as NH3 and H2S are either free or bound to airborne particular materials (PM) and are abundant and reactive. The aim of this current investigation was to explore the impacts of NH3 and/or H2S on male fertility and the underlying mechanisms. Male mouse exposed to H2S and/or NH3 and after two generations were used to evaluate the impacts on fertility. The fertility, and spermatozoa quality parameters and proteins involved in spermatogenesis were investigated. Our current investigation demonstrates: i) H2S and/or NH3 decrease male fertility by 20-30%, reduce the spermatozoa concentration about 20-40%, decrease 10-20%, increase around 30%; ii) the reduction in male fertility by H2S and/or NH3 can be inheritable; iii) H2S and/or NH3 can diminish male fertility through the disruption of spermatogenesis without affecting other body parameters such as body weight and organ index. One component of air pollutants, for example NH3, does not have a severe impact; however, two or more pollutants such as H2S and NH3 combined can cause serious health problems, especially with regard to male fertility. We suggest that greater attention should be paid to these air pollutants to improve human health and fertility.

[Screening of beta-lactoglobulin allergy-modulating lactobacilli strains using in vitro-in vivo correlation].

OBJECTIVE: We investigated the correlation between the in vitro immune profiling of 5 lactobacilli strains and their in vivo protective effect in a mouse beta-lactoglobulin (BLG) allergy model for selecting the candidate strains with potential anti-allergy activity. METHODS: In vitro immunomodulation was assessed by measuring interleukin (IL)-4 and interferon gamma (IFN-gamma) release by primary lymphocytes stimulated with 5 active/heat-killed lactobacilli. A mice model of beta-lactoglobulin allergy was then used to evaluate the alleviating allergy capacity of the same set of strains. The rats were randomly divided into blank group, BLG allergy group and different lactobacilli strains group. The total IgE and BLG-specific IgE contents in the serum of rats were measured with ELISA. Splenic lymphocytes were isolated and cultured in vitro, the levels of Thl/Th2 type cytokine were detected by ELISA. RESULTS: Protection of BLG-induced allergy was strain-specific. The strains displaying an in vitro capacity to induce higher levels of the Thl type cytokine (IFN-gamma) and lower levels of the Th2 type cytokine (IL-4), significantly decreased the levels of total IgE and BLG-IgE in allergic rat serum (P<0.05). In contrast, strains leading to a low IFN-gamma/IL-4 cytokine ratio could not significantly attenuate allergic symptoms. CONCLUSION: We could predict the in vivo protective capacity of the studied lactobacilli strains based on the cytokine profile established in vitro. Oral consumption of specific strain may be effective in preventing and alleviating BLG allergic symptoms by the improvement of the Th1/Th2 cell balance toward Th1 dominance, and the inhibition of IgE production.

[Effect of lactobacilli on Th1/Th2 cells balance in primary lymphocytes].

AIM: To analyse the effect of 7 Lactobacillus species on proliferation and cytokine production of primary lymphocytes, and explored the effect on the Th1/Th2 cells balance. METHODS: The mouse spleen cells were stimulated with active/heat-killed Lactobacillus strains at different species and concentrations. After be cultured with bacteria 60 hours, the proliferation of splenocytes were tested by MTT colorimetry, and IL-12, IFN-γ, IL-4, IL-10 and TGF-ß were detected by ELISA. RESULTS: (1) Both alive and heat-killed Lactobacillus species could accelerate the proliferation of spleen cells in a dose-dependent manner (P<0.05), the immuneological activity of heat-killed L.fermentum and L.acidophilu were not inferior to the live strains, especially when treated at higher dose(10(7);CFU/mL, bacteria: cell ratio of 10:1). Furthermore, these two heat-killed bacterial strains suppressed IL-4, IL-10 and TGF-ß production by stimulating IL-12 and IFN-γ production, and their IFN-γ/IL-4 value which represent the Th1/Th2 balance were higher than ConA control group significantly(P<0.05). CONCLUSION: The results indicate that Lactobacillus strains may differ in their respective ability to improve Th1/Th2 cells balance toward Th1 dominance via increasing the secretion ratio of IFN-γ/IL-4 (Th1/Th2) by splenocytes.