Thymocyte selection-associated high mobility box protein regulates T lymphocytes exhaustion in patients with myelodysplastic syndromes by inhibiting PI3K/AKT/mTOR pathway.

Myelodysplastic syndromes (MDS) patients often experience CD8+ T lymphocytes exhaustion, which plays a crucial role in the development of MDS. However, the specific role of thymocyte selection-associated high mobility box protein (TOX) in the CD8+ T lymphocytes exhaustion in MDS patients remains unclear. In this study, we investigated the role of TOX in CD8+ T lymphocytes exhaustion in patients with MDS. The expression of TOX, inhibitory receptors (IRs), and functional molecules in peripheral blood T lymphocytes of MDS patients and normal controls were detected using flow cytometry. Lentiviral transduction was used to create stable TOX-knockdown CD8+ T lymphocytes, and small interfering RNA (si-RNA) was used to knock down TOX in Jurkat cells. The expression of TOX was found to be significantly higher in CD8+ T lymphocytes of MDS patients compared to normal controls. This was associated with upregulated IRs and reduced expression of functional molecules such as Granzyme and Perforin. Myelodysplastic syndromes patients with higher TOX expression had poor clinical indicators and shorter survival. Knockdown of TOX using sh-RNA partially reverses the exhausted phenotype and enhances the lethality of CD8+ T lymphocytes. Moreover, the knockdown of TOX using si-RNA in Jurkat cells improved cell proliferation activity, down-regulated IRs and activated PI3K/AKT/mTOR signaling pathway. TOX promotes the exhaustion of CD8+ T lymphocytes by inhibiting PI3K/AKT/mTOR pathway, and targeted inhibition of TOX could partially restore the effector functions and activity of CD8+ T lymphocytes.

A nomogram model for predicting the efficacy of cyclosporine in patients with pure red cell aplasia.

Pure red cell aplasia (PRCA) is a rare bone marrow disorder characterized by a severe reduction or absence of erythroid precursor cells, without affecting granulocytes and megakaryocytes. Immunosuppressive therapies, particularly cyclosporine, have demonstrated efficacy as a primary treatment. This study aims to develop a predictive model for assessing the efficacy of cyclosporine in acquired PRCA (aPRCA). This retrospective study encompasses newly treated aPRCA patients at the General Hospital of Tianjin Medical University. Diagnosis criteria include severe anemia, and absolute reticulocyte count below 10 × 109/L, with normal white blood cell and platelet counts, and a severe reduction in bone marrow erythroblasts. Cyclosporine therapy was administered, with dose adjustments based on blood concentration. Response to cyclosporine was evaluated according to established criteria. Statistical analysis involved logistic multi-factor regression, generating a predictive model. The study included 112 aPRCA patients with a median age of 63.5 years. Patients presented with severe anemia (median Hb, 56 g/L) and reduced reticulocyte levels. Eighty-six patients had no bone marrow nucleated erythroblasts. Primary PRCA accounted for 62 cases (55.4%), and secondary PRCA accounted for 50 cases (44.6%). Univariate analysis revealed that ferritin, platelet to lymphocyte ratio (PLR), and CD4/CD8 ratio influenced treatment response. Multivariate analysis further supported the predictive value of these factors. A prediction model was constructed using ferritin, PLR, and CD4/CD8 ratio, demonstrating high sensitivity and specificity. The ferritin, PLR, and CD4/CD8-based nomogram showed good predictive ability for aPRCA response to cyclosporine. This model has potential clinical value for individualized diagnosis and treatment of aPRCA patients.

High TOX expression on CD8+ T cells in pure red cell aplasia.

Thymocyte selection-associated high-mobility group box protein (TOX) is an important molecule regulating the development and exhaustion of T lymphocytes. Our aim is to investigate the role of TOX in the immune pathogenesis of pure red cell aplasia (PRCA). TOX expression of CD8+ lymphocytes from the peripheral blood of patients with PRCA was detected by flow cytometry. Additionally, the expression of immune checkpoint molecules PD1 and LAG3 and cytotoxic molecules perforin and granzyme B of CD8+ lymphocytes was measured. The quantity of CD4+CD25+CD127low T cells was analyzed. TOX expression on CD8+ T lymphocytes in PRCA patients was significantly increased (40.73 [Formula: see text] 16.03 vs. 28.38 [Formula: see text] 12.20). The expression levels of PD1 and LAG3 on CD8+ T lymphocytes in PCRA patients were significantly higher than those in the control group (34.18 [Formula: see text] 13.26 vs. 21.76 [Formula: see text] 9.22 and 14.17 [Formula: see text] 13.74 vs. 7.24 [Formula: see text] 5.44, respectively). The levels of perforin and granzyme in CD8+ T lymphocytes of PRCA patients were 48.60 [Formula: see text] 19.02 and 46.66 [Formula: see text] 25.49, respectively, which were significantly higher than those of the control group (31.46 [Formula: see text] 7.82 and 16.17 [Formula: see text] 4.84, respectively). The number of CD4+CD25+CD127low Treg cells in PRCA patients was significantly decreased (4.30 [Formula: see text] 1.27 vs. 1.75 [Formula: see text] 1.22). In PRCA patients, CD8+ T cells were activated and exhibited overexpression of TOX, PD1, LAG3, perforin, and granzyme B, while regulatory T cells decreased. These findings suggest that T cell abnormality plays a critical role in the pathogenesis of PRCA.

Lactobacillus derived from breast milk facilitates intestinal development in IUGR rats.

AIM: The intestinal microbiota contributes to infant's intestine homeostasis. This study aimed to analyse how probiotics derived from breast milk promote infant intestinal development in rat pups. METHODS AND RESULTS: The effect of potential probiotics derived from breast milk on development of intrauterine growth retardation (IUGR) newborn rats' intestine was investigated. Limosilactobacillus oris ML-329 and Lacticaseibacillus paracasei ML-446 exhibited good hydrophobicity percentages (p < 0.05). ML-446 showed a significant effect on intestinal length and weight (p < 0.05). Meanwhile, the villus height of the IUGR newborn rats fed with ML-329 was significantly higher compared with those fed with Lacticaseibacillus rhamnosus GG (p < 0.05). Moreover, ML-329 and ML-446 both significantly stimulated the proliferation and differentiation of intestinal epithelial cells by increasing the number of ki67-positive cells, goblet cells, and lysozyme-positive Paneth cells (p < 0.05) through Wnt and Notch pathway. CONCLUSIONS: The proliferation and differentiation stimulating effects of ML-329 and ML-446 on IECs in the jejunum, ileum, and colon were mediated by activating the Wnt pathway with increased expression of wnt, lrp5, and ß-catenin genes and accumulation of ß-catenin, and by downregulating the Notch signalling pathway with decreased expression of the activated notch protein. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactobacillus could facilitate IUGR rat pups' intestinal development and enhance the proliferation of Paneth cells and goblet cells. These findings provide further insights into promotion of the intestinal development by breast milk-derived beneficial microbes in early life of the IUGR newborn rats.

Breast milk contains probiotics with anti-infantile diarrhoea effects that may protect infants as they change to solid foods.

Infants often experience complementary food-induced diarrhoea (CFID), which occurs when infants switch from breast milk to solid foods. The relative abundances of Prevotella and Rothia were higher in stools of infants with CFID, while the relative abundances of Enterococcus and Escherichia were higher in healthy infants. The abundance of Lactobacillus spp. normally found in breast milk fed to infants with CFID was significantly reduced, and Enterococcus spp. were less abundant when diarrhoea occurred. Furthermore, Lactobacillus and Enterococcus were present as shared bacteria in both mother and infant, and they were considered potential anti-CFID probiotics as their relative abundances in breast milk were negatively correlated to infant CFID. Kyoto encyclopedia of genes and genomes (KEGG) functional analysis showed that the function of amino acid metabolism differed between infants with CFID and healthy infants. Therefore, CFID might be related to the decomposition of proteins in food supplements. The screening revealed seven hydrolytic casein and five hydrolytic casein and rice protein isolates from 320 suspected Lactobacillus and Enterococcus isolates. The animal experiments demonstrated that a mixture of five isolates effectively hydrolysed the casein and rice protein and prevented diarrhoea in young rats. Thus, the occurrence of CFID was found to be closely related to the intestinal and breast milk microbiota, and bacteria that could assist in the digestion of cereal proteins were involved in CFID.

Imbalance between peptidoglycan synthases and hydrolases regulated lysis of Lactobacillus bulgaricus in batch culture.

Lactobacillus bulgaricus is an important starter culture in the dairy industry, cell lysis is negative to the high density of this strain. This work describes the response of peptidoglycan synthases and hydrolases in Lactobacillus bulgaricus sp1.1 when pH decreasing in batch culture. First, the cell lysis was investigated by measuring the cytosolic lactate dehydrogenase released to the fermentation broth, a continuous increase in extracellular lactate dehydrogenase was observed after the lag phase in batch culture. Then, the peptidoglycan hydrolases profile analyzed using the zymogram method showed that eight proteins have the ability of peptidoglycan hydrolysis, three of the eight proteins were considered to contribute lysis of L. bulgaricus sp1.1 according to the changes and extents of peptidoglycan hydrolysis. In silico analysis showed that three putative peptidoglycan hydrolases, including N-acetylmuramyl-L-Ala amidase (protein ID: ALT46642.1), amidase (protein ID: ALT46641.1), and N-acetylmuramidase (protein ID: WP_013439201.1) were compatible with these proteins. Finally, the transcription of the three putative peptidoglycan hydrolases was upregulated in batch culture, in contrast, the expression of four peptidoglycan synthases was downregulated. These observations suggested the imbalance between peptidoglycan synthases and hydrolases involved in the lysis of Lactobacillus bulgaricus sp1.1.

Abnormal Macrophage Polarization in Patients with Myelodysplastic Syndrome.

BACKGROUND: This study is aimed at assessing the subsets of bone marrow macrophages in patients with myelodysplastic syndrome (MDS) and exploring the role of macrophages in the pathogenesis of MDS. METHODS: Thirty-eight newly diagnosed MDS patients were enrolled in the Department of Hematology of General Hospital of Tianjin Medical University from June 2015 to June 2016. Bone marrow monocytes and macrophage subsets (M1/M2) were detected in patients with MDS and normal controls by flow cytometry. M1 macrophages were cultured in vitro, and the expression of IL-1ß and TNF-α mRNA was measured using real-time polymerase chain reaction. RESULTS: Compared with the normal control group, the proportion of bone marrow monocytes was higher (2.11 ± 0.93% vs. 3.66 ± 3.38%), and the mean fluorescence intensity of surface molecule CD14 was lower in the higher-risk (HR) MDS group (639.05 ± 359.78 vs. 458.26 ± 306.72, p < 0.05). The ratio of M2 macrophages to monocytes was higher in patients with HR-MDS (1.82 ± 2.47% vs. 3.93 ± 3.81%, p < 0.05). The ratio of M1 to M2 macrophages was lower in the HR-MDS group (3.50 ± 3.22 vs. 1.80 ± 0.88, p < 0.05). The expression of IL-1ß and TNF-α mRNA in M1 macrophages was significantly lower in the MDS group (p < 0.05). CONCLUSIONS: Patients with MDS had abnormal macrophage polarization, which may be involved in the alteration of bone marrow microenvironments.

Profiles of Intestinal Flora in Breastfed Obese Children and Selecting Functional Strains Against Obesity.

SCOPE: Breast milk has the potential to prevent childhood obesity by providing probiotics, but there are still instances of obesity in breastfed children. METHODS AND RESULTS: This study investigates the difference in intestinal flora structure between breastfed children with obesity (OB-BF) and normal-weight breastfed children (N-BF). Building upon this foundation, it employs both cell and mouse models to identify an antiobesity strain within the fecal matter of N-BF children and explore its underlying mechanisms. The results reveal a reduction in lactobacillus levels within the intestinal flora of OB-BF children compared to N-BF children. Consequently, Lactobacillus plantarum H-72 (H-72) is identified as a promising candidate due to its capacity to stimulate glucagon-like peptide-1 (GLP-1) secretion in enteroendocrine cells (ECCs). In vivo, H-72 effectively increases serum GLP-1 concentration, reduces food intake, regulates the expression of genes related to energy metabolism (SCD-1, FAS, UCP-1, and UCP-3), and regulates gut microbiota structure in mice. Moreover, the lipoteichoic acid of H-72 activates toll-like receptor 4 to enhanced GLP-1 secretion in STC-1 cells. CONCLUSIONS: L. plantarum H-72 is screened out for its potential antiobesity effect, which presents a potential and promising avenue for future interventions aimed at preventing pediatric obesity in breastfed children.

Whole-genome analysis, evaluation and regulation of in vitro and in vivo GABA production from Levilactobacillus brevis YSJ3.

Gamma-aminobutyric acid (GABA) produced by lactic acid bacteria (LAB) is safe and has several health benefits. Levilactobacillus brevis YSJ3 was selected from 110 LAB. It exhibited the highest in vitro GABA production level of 970.10 µg/mL. Whole-genome analysis revealed that L. brevis YSJ3 contained gadR, gadC, gadB and gadA. Furthermore, the Luedeking-Piret model was fitted, which indicated that GABA production was divided into three stages. The gadR 0079, gadC 0080, and gadB 0081 were confirmed to promote GABA synthesis. Moreover, 55 metabolites, particularly those involved in arginine metabolism, were significantly different at 6 and 20 h of cultivation. Notably, L. brevis YSJ3 significantly improved sleep in mice and increased GABA levels in the mice's gut compared with the control group. This suggests that the oral administration of L. brevis YSJ3 improves sleep quality, probably by increasing intestinal GABA levels. Overall, L. brevis YSJ3 was confirmed as a GABA-producing strain in vitro and in vivo, making it a promising probiotic candidate for its application in food and medicine.

TOX regulates T lymphocytes differentiation and its function in tumor.

Thymocyte selection-associated high mobility group box protein (TOX) is expressed differently at all T lymphocytes development stages. Owing to more advanced scientific and technological means, including single-cell sequencing technology, heterogeneity of T lymphocytes and TOX has gradually been revealed. Further exploration of such heterogeneity will help us comprehend the developmental stage and functional characteristics of T lymphocytes in greater detail. Emerging evidence supports its regulation not only in exhausting, but also in activating T lymphocytes, thereby verifying TOX heterogeneity. TOX can be used not only as a latent intervention target for tumor diseases and chronic infections, and a therapeutic strategy for autoimmune diseases, but also as a critical factor predicting the drug response and overall survival of patients with malignant tumors.

The Effect of Decreased Ca++/Mg++ ATPase Activity on Lactobacillus delbrueckii subsp. bulgaricus sp1.1 Survival during Spray Drying.

Compared with the commonly used technique of freeze-drying, spray drying has lower energy costs. However, spray drying also has a fatal disadvantage: a lower survival rate. In this study, the survival of bacteria in a spray-drying tower decreased as the water content was reduced. The water content of 21.10% was the critical point for spray drying Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) sp1.1 based on sampling in the tower. Based on the relationship between the moisture content of spray drying and the survival rate, the water content of 21.10% was also the critical point for the change in the survival rate during spray drying. Proteomic analysis was used to investigate the reasons for L. bulgaricus sp1.1 inactivation during and after spray drying. Gene Ontology (GO) enrichment revealed that differentially expressed proteins were mainly associated with the cell membrane and transport. In particular, proteins related to metal ion transport included those involved in the transport of potassium, calcium and magnesium ions. The protein-protein interaction (PPI) network revealed that Ca++/Mg++ adenosine triphosphatase (ATPase) may be a key protein. Ca++/Mg++ ATPase activity decreased substantially during spray drying (p < 0.05). Supplementation with Ca++ and Mg++ significantly increased the expression of ATPase-related genes and enzyme activity (p < 0.05). The Ca++/Mg++ ATPase activity of L. bulgaricus sp1.1 was enhanced by increasing the intracellular Ca++ or Mg++ concentration, thus increasing the survival of spray-dried LAB. Bacterial survival rates were increased to 43.06% with the addition of Ca++ and to 42.64% with the addition of Mg++, respectively. Ca++/Mg++ ATPase may be the key to the damage observed in spray-dried bacteria. Furthermore, the addition of Ca++ or Mg++ also reduced bacterial injury during spray drying by enhancing the activity of Ca++/Mg++ ATPase.

Reduced formation of biogenic amines in low-salt Zhacai via fermentation under CO2-modified atmosphere.

Reducing sodium salt content in traditional fermented vegetables and developing low-salt fermented products have attracted increasing attention.However, low-salt fermented vegetables are prone to accumulate toxic biogenic amines (BAs) caused by the undesirable metabolism of spoilage microorganisms. This study aimed to investigate the impact of a CO2-modified atmosphere (MA) approach to the fermentation of low-salt Zhacai and the accumulation of BAs. The results show CO2-MA effectively suppressed the production of excessive BAs in low-salt Zhacai, as evidenced by a decrease in the total BA content from 63.66 to 161.41 mg/ kg under natural air conditions to 1.88-24.76 mg/ kg under CO2-MA. Overall, the mechanism of hindering BA formation was closely related to the change in the microbial community and the downregulation of BA-producing enzymes. Lactic acid bacteria, including Lactiplantibacillus plantarum, Weissella spp., and Pediococcus spp., were enriched under CO2-MA, whereas amine-producing microorganisms (e.g., Halomonas spp., Psychrobacter spp., Corynebacterium spp., and Levilactobacillus brevis) were greatly inhibited. Moreover, metagenomic analysis revealed that genes encoding amino acid decarboxylase, amine deiminase, and amine synthase were downregulated, which could be the fundamental reason for BA reduction. This study provides an alternative method for reducing BA production in fermented food.

Lactobacillus rhamnosus MN-431 Metabolic Tryptophan Alleviates Complementary Food-Induced Diarrhea through PXR-NF-κB Pathway and AHR-Th17 Cell Response Pathways.

SCOPE: Lactobacillus rhamnosus MN-431 tryptophan broth culture (MN-431 TBC) can prevent complementary food-induced diarrhea (CFID). However, it is not clear whether this effect is related to indole derivatives. METHODS AND RESULTS: In this study, the anti-CFID effects of different components in MN-431 TBC including MN-431 cells, unfermented tryptophan broth, and supernatant of MN-431 TBC (MN-431 TBS) are investigated. Only MN-431 TBS can significantly prevent CFID, indicating that indole derivatives produced by MN-431 can exert antidiarrheal effects. Intestinal morphological analysis reveals that MN-431 TBS can increase the number of goblet cells, height of ileal villi, and length of rectal glands while also increasing the expression of ZO-1 in colon. Furthermore, HPLC analysis reveals the indole derivatives in MN-431 TBS are IAld and skatole. Cell experiments demonstrate that MN-431 TBS promotes the transcription of aryl hydrocarbon receptor (AHR) and pregnane X receptor (PXR), comparable to the synergistic effect of IAld and skatole. MN-431 TBS can activate AHR and reduces the concentrations of Th17 cell-inflammatory factors IL-17A and IL-21 in intestine and IL-17F, IL-21, and IL-22 in serum. MN-431 TBS can also activate PXR and reduces the concentrations of TNF-α and IL-6 in intestine and serum. CONCLUSION: MN-431 TBS, containing IAld and skatole, can exert anti-CFID effects through the AHR-Th17 and PXR-NF-κB pathways.

Phagocytosis checkpoints on hematopoietic stem cells in patients with myelodysplastic syndromes.

BACKGROUND: The myelodysplastic syndrome (MDS) is a high-risk hemocytopenia easily converted to acute myeloid leukemia. CD47 plays an important role in regulating phagocytosis, and its role in the pathogenesis of MDS is unclear. METHODS: CD47 and PI3K/AKT/mTOR on CD34+ CD38- cells were detected by flow cytometry. NF-κB, PI3K, AKT, PTEN, and mTOR mRNA overexpressed in CD34+ CD38- CD47+ cells were performed by real-time quantitative transcriptase-polymerase chain reaction. Phagocytic capacity of macrophages was measured with carboxyfluorescein succinimidyl ester and fluorescent microspheres. Sorted CD34+ CD38- CD47+ cells were injected into NOD-Prkdcscid Il2rgnull mice. RESULTS: The expression of CD47 on CD34+ CD38- cells of the patients in high-risk MDS based on IPSS-R/WPSS score was higher than that in low-risk MDS and controls. The signaling pathway of PI3K/AKT/mTOR is active in CD34+ CD38- CD47+ cells of MDS patients. CD47 overexpressing CD34+ CD38- cells has antiphagocytosis. CD47 overexpressing leukemia stem cell (LSC) -transplanted mice has a short survival time. The macrophages originated from MDS might elicit a pro-tumor response in MDS by inhibiting phagocytosis. CONCLUSIONS: Phagocytosis checkpoints are impaired in MDS. High expression of CD47 on CD34+CD38- cells indicates poor clinical prognosis in MDS.

Effect of Lactobacillus rhamnosus MN-431 Producing Indole Derivatives on Complementary Feeding-Induced Diarrhea Rat Pups Through the Enhancement of the Intestinal Barrier Function.

SCOPE: Many infants suffer from complementary feeding-induced diarrhea (CFID). Studies have shown that intestinal microbes can enhance the intestinal barrier and prevent diarrhea by producing indole derivatives that promote pregnane X receptor (PXR) expression. METHODS AND RESULTS: In this study, the indole test and determination of the PXR concentration are performed on tryptophan broth cultures of 320-suspected Lactobacillus and Enterococcus strains. Four strains that produce indole derivatives that promote the expression of PXR are screened as potential functional probiotics. Both Lactobacillus rhamnosus MN-431 (L. rhamnosus MN-431) and Lactobacillus oris FN-448 (L. oris FN-448) can colonize the intestine of rat pups, and L. rhamnosus MN-431 can significantly decrease the incidence of diarrhea and intestinal permeability in rat pups. Using real-time qPCR and the analysis of the intestinal morphology using immunohistochemistry, it is observed that the metabolized tryptophan from L. rhamnosus MN-431 can reduce small intestinal mucosal damage by stimulating PXR/NF-κB signaling and activating PXR and aryl hydrocarbon receptor. The intestinal barrier is also enhanced by promoting the expression of tight junction proteins such as Occludin and zonula occludens-1 in baby rats. CONCLUSION: The results demonstrate that L. rhamnosus MN-431 can metabolize tryptophan to prevent infantile CFID by promoting the expression of PXR.

[Inhibitory Effect of Ascorbic Acid on Myelodysplastic Syndrome Cells and Its Mechanism].

OBJECTIVE: To investigate the inhibitory effect of ascorbic acid single or combination of decitabine on tumor cells of myelodysplastic syndrome (MDS) and explore its related mechanism. METHODS: The human MDS cell lines SKM-1 and MUTZ-1 were treated with different concentrations of ascorbic acid, and the cell proliferation activity was detected by the CCK-8 assay. The reactive oxygen species (ROS) level, labile iron pool (LIP), cell cycle, and apoptosis of SKM-1 and MUTZ-1 cells were detected by flow cytometry. The control group, ascorbic acid monotherapy group, decitabine monotherapy group, and combination group of ascorbic acid and decitabine were set up, the cell proliferation activity and apoptosis were detected in each group. RESULTS: High-dose ascorbic acid could reduce the cell proliferation activity of SKM-1 (R=0.886, p=0.000) and MUTZ-1 (R=0.880, p=0.000). With the increase of ascorbic acid concentration, the ROS level in SKM-1 and MUTZ-1 cells increased (r=0.816, r=0.942), the proportion of cells stagnation in G2 phase increased (r=0.970, p=0.000; r=0.962, p=0.000), the proportion of surviving cells decreased (r=-0.966, p=0.000; r=-0.952, p=0.000), and the apoptosis cells significantly increased (r=0.966, p=0.000; r=0.958, p=0.000). Nevertheless, the level of LIP showed no significant changes. After the combined application of ascorbic acid and decitabine, MDS tumor cells showed decreased proliferative activity and increased apoptosis compared with single-agent ascorbic acid and decitabine group. CONCLUSION: High-dose ascorbic acid shows a cytotoxic effect on MDS tumor cells, inhibiting cell proliferation and increasing apoptosis. Ascorbic acid combined decitabine have a synergistic effect of anti-MDS tumor cells.

Low- and intermediate-risk myelodysplastic syndrome with pure red cell aplasia.

OBJECTIVES: Our aim is to investigate the clinical characteristics of low- and intermediate-risk myelodysplastic syndrome (MDS) with pure red cell aplasia (PRCA). METHODS: We retrospectively reviewed the patients of low- and intermediate-risk MDS patients who had been diagnosed with PRCA in our hospital between January 2010 and December 2019. RESULTS: There were 6 low- and intermediate-risk MDS patients with PRCA in our study, 1 male and 5 females, with a median age of 63.5 (50-75) years. It accounted for 7.7% (6/78) of all diagnosed PRCA cases and 1.67% (6/359) of diagnosed MDS cases during the same period. All patients were treated with multiple drugs, including recombinant human erythropoietin, cyclosporine, glucocorticoids, androgen, sirolimus, intravenous immunoglobulin and decitabine. Two patients achieved complete remission, two patients achieved partial remission and became blood transfusion independent. Two patients had no response and one patient died. CONCLUSION: Low- and intermediate-risk MDS with PRCA was difficult to treat, but the prognosis was good.

Influence of Lactic Acid on Cell Cycle Progressions in Lactobacillus bulgaricus During Batch Culture.

Lactic acid has been proved to inhibit the proliferation of lactic acid bacteria in the fermentation process. To shed light on the cell cycle alterations in acidic conditions, the cell division of Lactobacillus bulgaricus sp1.1 in batch culture was analyzed directly by implementing of the intracellular fluorescent tracking assay in different pH adjusted by lactic acid. Cell proliferation and cell division were investigated to be negatively controlled by the decrease of pH, and pH 4.1 was the critical condition of downregulating cell division but retains cell culturability. The cell area and cell length in pH 4.1 were examined by using fluorescent labeling, and they reduced to about 29.18-34.89% and 32.67-40% of cells cultured in the unacidified medium, respectively. The DNA replication initiation was undergoing prompted by the low extent of DNA condensation and higher expression of the dnaA gene in this critical pH. The results indicated that the cell cycle progressions of Lactobacillus bulgaricus sp1.1 in acidic conditions were arrested at intracellular biomass accumulation and cell division stage. These findings provide fundamental insight into cell cycle control of the acidic environment in Lactobacillus bulgaricus sp1.1.

Lactiplantibacillus plantarum H-87 prevents high-fat diet-induced obesity by regulating bile acid metabolism in C57BL/6J mice.

Bile salt hydrolase (BSH)-producing bacteria are negatively related to the body weight gain and energy storage of the host. We aimed to obtain a novel BSH-producing strain with excellent anti-obesity effect and explained its mechanism. Here, we selected a strain named Lactiplantibacillus plantarum H-87 (H-87) with excellent ability to hydrolyze glycochenodeoxycholic acid (GCDCA) and tauroursodeoxycholic acid (TUDCA) in vitro from 12 lactobacilli, and evaluated its anti-obesity effect in high-fat diet (HFD)-fed C57BL/6J mice. The results suggested that H-87 could inhibit HFD-induced body weight gain, fat accumulation, liver lipogenesis and injury, insulin resistance and dyslipidemia. In addition, H-87 could colonize in the ileum and hydrolyze GCDCA and TUDCA, reflected as changes in the concentrations of GCDCA, TUDCA, CDCA and UDCA in the ileum or liver. Furthermore, the study identified that H-87 reduced TUDCA and GCDCA levels in the ileum, which decreased the GLP-1 secretion by L cells to alleviate insulin resistance in HFD-fed mice. Furthermore, H-87 increased the CDCA level in the ileum and liver to activate FXR signaling pathways to inhibit liver lipogenesis in HFD-fed mice. In addition, the decrease of intestinal conjugated bile acids (TUDCA and GCDCA) also increased fecal lipid content and decreased intestinal lipid digestibility. In conclusion, H-87 could inhibit liver fat deposition, insulin resistance and lipid digestion by changing bile acid enterohepatic circulation, and eventually alleviate HFD-induced obesity.