Inhibiting circ_0000673 blocks the progression of colorectal cancer through downregulating CPSF6 via targeting miR-548b-3p.

BACKGROUND: Colorectal cancer (CRC) is one of the most common cancers, and its progression is regulated by several factors, including circular RNA (circRNA). OBJECTIVES: The objective of this study was to determine the role, or roles, of circ_0000673 in CRC. MATERIAL AND METHODS: We used quantitative real-time polymerase chain reaction (qPCR) to detect the expression of circ_0000673, miR-548b-3p and cleavage and polyadenylation specific factor 6 (CPSF6) in DLD-1 and RKO cells. Cell Counting Kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EdU) assays were used to determine circ_0000673 roles in proliferation. Wound healing and transwell assays were used to detect cell migration and invasion abilities. Expression of CPSF6 protein and stem cell-associated proteins were examined using western blot. The putative relationship between miR-548b-3p and circ_0000673 or CPSF6 was verified with dual-luciferase reporter assay. The role of circ_0000673 in CRC was also investigated in a tumor xenograft assay in nude mice. RESULTS: Circ_0000673 expression was increased in CRC tissues and cancer cells. Silencing circ_0000673 reduced tumor cell proliferation, migration and invasion, while also decreasing cell stemness. MiR-548b-3p was found to be a target of circ_0000673, while CPSF6 was a downstream target of miR-548b-3p. The tumor-regulatory effects of si-circ_0000673, anti-miR-548b-3p and oe-CPSF6 were partially reversed by anti-miR-548b-3p, si-CPSF6 and si-circ_0000673, respectively, in rescue assays. Downregulation of circ_0000673 reduced solid tumor growth in vivo. CONCLUSIONS: Circ_0000673 inhibition reduced CPSF6 expression by targeting miR-548b-3p, thereby blocking proliferation, migration and invasion of CRC tumor cells.

Crizotinib and its enantiomer suppress ferroptosis by decreasing PE-O-PUFA content.

Ferroptosis is a specific form of cell death characterized by excessive accumulation of cellular lipid peroxides. Ferroptosis is closely associated with various diseases, inhibition of which may help alleviate multi-organ injury caused by ischemia-reperfusion and enhance the anti-tumor effect by promoting the immunity of T cells. However, clinical approved drugs targeting ferroptosis process remain rare. In this study, we unexpectedly found that (R)-crizotinib, the first-generation ALK inhibitor, has potent inhibitory activity against ferroptosis across various cell lines. Moreover, its chiral molecule (S)-crizotinib, which was considered to share no common targets with (R)-crizotinib, also suppresses ferroptosis with an efficacy similar to that of (R)-crizotinib. We further demonstrated that both crizotinib enantiomers inhibit ferroptosis independently of their known targets, but through a common mechanism involving the targeting of AGPAT3-mediated synthesis of ether-linked polyunsaturated fatty acids (PE-O-PUFA), which are known to promote lipid-ROS generation and ferroptosis. In line with their activity in cell lines, (R)-crizotinib and (S)-crizotinib effectively mitigate renal ischemia-reperfusion injury in mice. Furthermore, the two compounds also inhibit lipid-ROS accumulation in CD8+ T cells in draining lymph nodes of B16-F10 subcutaneous xenograft mice, thereby promoting anti-tumor effects. Collectively, our study firstly reports a common activity shared by (R)-crizotinib and (S)-crizotinib in ferroptosis regulation. As a clinically approved drug, (R)-crizotinib has well-established pharmacokinetics and safety, which makes it a promising candidate for repurposing. Given the current lack of FDA-approved ferroptosis inhibitors, our findings suggest therapeutically repurposing (R)-crizotinib as well as its enantiomer (S)-crizotinib for treating ferroptosis-related diseases.

Peteryoungia algae sp. nov. isolated from seaweeds of Gouqi Island, China, and its unique genetic features among Peteryoungia strains.

A Gram-stain-negative, light khaki, strictly aerobic, rod-shaped, motile via multiple flagella, and catalase- and oxidase-positive bacterium, designated as SSM4.3T, was isolated from the seaweed of Gouqi Island in the East China Sea. The novel isolate grows at 0-5.0% NaCl concentrations (w/v) (optimum 1%), pH 5.0-9.0 (optimum pH 7.0), and 15-37 °C (optimum 30 °C). The 16S rRNA gene sequences-based phylogeny indicates that the novel marine isolate belongs to the family Rhizobiaceae and that it shared the greatest sequence similarity (98.9%) with Peteryoungia rhizophila CGMCC 1.15691T. This classification was also supported by phylogenetic analysis using core genes. The predominant fatty acids (≥ 10%) of the strain were identified as C18:1 ω7c/C18:1 ω6c. Q-10 was identified as the major isoprenoid quinone, with trace levels of Q-9 present. The major polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The complete genome size of strain SSM4.3T is 4.39 Mb with a DNA G+C content of 61.3%. The average nucleotide identity, digital DNA-DNA hybridization, and average amino acid identity values between the genomes of strain SSM4.3T and its closely related representatives were 74.80-86.93%, 20.00-32.30%, and 70.30-91.52%, respectively. Phylogenetic analysis, grounded on the core genes, reveals the evolutionary relationship between SSM4.3T and other Peteryoungia strains. Pan-genomics analysis of 8 previously classified Peteryoungia species and SSM4.3T revealed their unique genetic features and functions. Overall, strain SSM4.3T was considered to be a new species of the Peteryoungia genus; the name Peteryoungia algae sp. nov. has been proposed, with type strain SSM4.3T (= LMG 32561 = MCCC 1K07170).

Characterization and Genomic Analysis of Affinirhizobium gouqiense sp. nov. Isolated from Seawater of Gouqi Island Located in the East China Sea and Reclassification of Rhizobium lemnae to the Genus Affinirhizobium as Affinirhizobium lemnae comb. nov.

A novel bacterium designated as SSA5.23T was isolated from seawater. Cells of SSA5.23T are Gram-stain-negative, short, rod-shaped, and exhibit motility via numerous peritrichous flagella. The strain could grow at temperatures ranging from 15 to 35 °C (optimum at 25 °C), in a salinity range of 0-5.0% (w/v) NaCl, and within a pH range of 6.0-9.0 (optimum at pH 7.0). The predominant cellular fatty acid of SSA5.23T was C18:1 ω7c/C18:1 ω6c, and the major respiratory quinones were Q-9 and Q-10. Diphosphatidylglycerol, phosphatidylethanolamine, and phosphatidylglycerol were identified as the primary polar lipids. The complete genome (5.47 Mb) of SSA5.23T comprises of a circular chromosome of 3.64 Mb and three plasmids, specifically sized at 59.73 kb, 227.82 kb, and 1.54 Mb, respectively. Certain genes located on the plasmids play roles in denitrification, oxidative stress resistance, and osmotic tolerance, which likely contribute to the adaptability of this strain in marine conditions. Core-proteome average amino acid identity analysis effectively identified the strain's affiliation with the genus Affinirhizobium, showing the highest value (89.9%) with Affinirhizobium pseudoryzae DSM 19479T. This classification was further supported by the phylogenetic analysis of concatenated alignment of 170 single-copy orthologous proteins. When compared to related reference strains, SSA5.23T displayed an average nucleotide identity ranging from 74.9 to 80.3% and digital DNA-DNA hybridization values ranging from 19.9 to 23.9%. Our findings confirmed that strain SSA5.23T represents a novel species of the genus Affinirhizobium, for which the name Affinirhizobium gouqiense sp. nov. (type strain SSA5.23T = LMG 32560T = MCCC 1K07165T) was suggested.

Atramacronoid A induces the PANoptosis-like cell death of human breast cancer cells through the CASP-3/PARP-GSDMD-MLKL pathways.

Breast cancer is the most common malignant tumor and a major cause of mortality among women worldwide. Atramacronoid A (AM-A) is a unique natural sesquiterpene lactone isolated from the rhizome of Atractylodes macrocephala Koidz (known as Baizhu in Chinese). Our study demonstrated that AM-A triggers a specific form of cell death resembling PANoptosis-like cell death. Further analysis indicated that AM-A-induced PANoptosis-like cell death is associated with the CASP-3/PARP-GSDMD-MLKL pathways, which are mediated by mitochondrial dysfunction. These results suggest the potential of AM-A as a lead compound and offer insights for the development of therapeutic agents for breast cancer from natural products.

Analysis of immune cells and risk factors related to lower limb deep vein thrombosis in patients with cerebral infarction.

To explore the characteristics of hematologic indicators and related risk factors of lower extremity deep vein thrombosis (LDVT) in patients with cerebral infarction. METHODS: This study retrospectively analyzed data from 174 patients with cerebral infarction admitted to The Rehabilitation Department of Shanghai Fifth Rehabilitation Hospital and Shanghai First People's Hospital from June 2022 to June 2023. Based on the results of lower limb venous color Doppler ultrasound examinations, patients were divided into two groups: the LDVT group (35 cases) and the non-LDVT group (139 cases). We compared the clinical data and hematologic indicators (D-dimer value, fibrinogen, white blood cells, platelets, uric acid, creatinine, etc.) of the two groups to identify the risk factors of cerebral infarction complicated with LDVT. RESULTS: Statistical analysis revealed that the D-dimer values of the LDVT group were significantly (P<0.05) higher than those of the non-LDVT group. The uric acid value of the LDVT group was significantly lower than that of the non-LDVT group, with statistical significance (P<0.05). The Brunnstrom staging in the LDVT group was significantly different from that in the non-LDVT group (P<0.05). Meanwhile, binary logistic regression analysis showed that LDVT complicated with cerebral infarction was associated with D-dimer level [OR=1.302, 95% CI (1.077, 1.575)], uric acid level [OR=0.995, 95% CI (0.990, 1.000)], and Brunnstrom staging [OR=3.005, 95% CI (1.312, 6.880)]. CONCLUSION: D-dimer value, uric acid value, and Brunnstrom stage I to II are closely related to the occurrence of LDVT in patients with cerebral infarction. High D-dimer value, low uric acid value, and Brunnstrom stage I to II are independent risk factors for LDVT in cerebral infarction. Early assessment of D-dimer value, uric acid value, and Brunnstrom stage of cerebral infarction should be considered in clinical practice.

[Intervention Effect and Mechanism of Regulating MiR-155 on Young Rats with Dysfunction of Blood Coagulation].

OBJECTIVE: To investigate the intervention effect and mechanism of regulating miR-155 on young rats with dysfunction of blood coagulation. METHODS: Twenty-six healthy and clean SD male rats were selected to establish the coagulopathy models. Twenty-four rats successfully established models and were randomly divided into three groups: model group, up-regulated miR-155 group and down-regulated miR-155 group, with 8 rats in each group. The expression of miR-155 was detected by real-time fluorescence quantitative polymerase chain reaction. The changes of coagulation factors and coagulation indicators were observed. Liver pathological tissues were observed by HE staining. The expressions of HMGB1-RAGE/TLRs-NF-κB signaling pathway related proteins were detected by Western blot. RESULTS: Compared with model group, the expressions of HMGB1, RAGE, TLR2, TLR4 and NF-κB were significantly increased in up-regulated miR-155 group (all P < 0.05), while decreased in down-regulated miR-155 group (all P < 0.05). Compared with model group, the expressions of coagulation factor Ⅱ, Ⅶ, Ⅸ, and Ⅹ were significantly decreased in up-regulated miR-155 group (all P < 0.05), while increased in down-regulated miR-155 group (P < 0.05). There was no significant difference in the expression of coagulation factor Ⅺ among the three groups (P >0.05). Compared with model group, the levels of prothrombin time (PT) and activated partial thromboplastin time (APTT) were lower and fibrinogen (FIB) was higher in up-regulated miR-155 group (all P < 0.05), while in the down-regulated miR-155 group they were opposite. CONCLUSION: Down-regulation of miR-155 can effectively improve coagulation factors and coagulation indexes and inhibit inflammation in young rats with dysfunction of blood coagulopathy, and the mechanism may be related to HMGB1-RAGE/TLRs-NF-κB signaling pathway.

Mitochondrial endogenous substance transport-inspired nanomaterials for mitochondria-targeted gene delivery.

Mitochondrial genome (mtDNA) independent of nuclear gene is a set of double-stranded circular DNA that encodes 13 proteins, 2 ribosomal RNAs and 22 mitochondrial transfer RNAs, all of which play vital roles in functions as well as behaviors of mitochondria. Mutations in mtDNA result in various mitochondrial disorders without available cures. However, the manipulation of mtDNA via the mitochondria-targeted gene delivery faces formidable barriers, particularly owing to the mitochondrial double membrane. Given the fact that there are various transport channels on the mitochondrial membrane used to transfer a variety of endogenous substances to maintain the normal functions of mitochondria, mitochondrial endogenous substance transport-inspired nanomaterials have been proposed for mitochondria-targeted gene delivery. In this review, we summarize mitochondria-targeted gene delivery systems based on different mitochondrial endogenous substance transport pathways. These are categorized into mitochondrial steroid hormones import pathways-inspired nanomaterials, protein import pathways-inspired nanomaterials and other mitochondria-targeted gene delivery nanomaterials. We also review the applications and challenges involved in current mitochondrial gene editing systems. This review delves into the approaches of mitochondria-targeted gene delivery, providing details on the design of mitochondria-targeted delivery systems and the limitations regarding the various technologies. Despite the progress in this field is currently slow, the ongoing exploration of mitochondrial endogenous substance transport and mitochondrial biological phenomena may act as a crucial breakthrough in the targeted delivery of gene into mitochondria and even the manipulation of mtDNA.

Herb pair of Huangqi-Danggui exerts anti-tumor immunity to breast cancer by upregulating PIK3R1.

BACKGROUND: According to traditional Chinese medicine (TCM), drugs supplementing the vital energy, Qi, can eliminate tumors by restoring host immunity. The objective of this study is to investigate the underlying immune mechanisms of anti-tumor activity associated with Qi-supplementing herbs, specifically the paired use of Huangqi and Danggui. METHODS: Analysis of compatibility regularity was conducted to screen the combination of Qi-supplementing TCMs. Using the MTT assay and a transplanted tumor mice model, the anti-tumor effects of combination TCMs were investigated in vitro and in vivo. High content analysis and flow cytometry were then used to evaluate cellular immunity, followed by network pharmacology and molecular docking to dissect the significant active compounds and potential mechanisms. Finally, the anti-tumor activity and the mechanism of the active ingredients were verified by molecular experiments. RESULTS: There is an optimal combination of Huangqi and Danggui that, administered as an aqueous extract, can activate immunity to suppress tumor and is more effective than each drug on its own in vitro and in vivo. Based on network pharmacology analysis, PIK3R1 is the core target for the anti-tumor immunity activity of combined Huangqi and Danggui. Molecular docking analysis shows 6 components of the combined Danggui and Huangqi extract (quercetin, jaranol, isorhamnetin, kaempferol, calycosin, and suchilactone) that bind to PIK3R1. Jaranol is the most important component against breast cancer. The suchilactone/jaranol combination and, especially, the suchilactone/kaempferol combination are key for immunity enhancement and the anti-tumor effects of the extract. CONCLUSIONS: The combination of Huangqi and Danggui can activate immunity to suppress breast cancer and is more effective than the individual drugs alone.

PCK2 maintains intestinal homeostasis and prevents colitis by protecting antibody-secreting cells from oxidative stress.

Maintaining intracellular redox balance is essential for the survival, antibody secretion, and mucosal immune homeostasis of immunoglobulin A (IgA) antibody-secreting cells (ASCs). However, the relationship between mitochondrial metabolic enzymes and the redox balance in ASCs has yet to be comprehensively studied. Our study unveils the pivotal role of mitochondrial enzyme PCK2 in regulating ASCs' redox balance and intestinal homeostasis. We discover that PCK2 loss, whether globally or in B cells, exacerbates dextran sodium sulphate (DSS)-induced colitis due to increased IgA ASC cell death and diminished antibody production. Mechanistically, the absence of PCK2 diverts glutamine into the TCA cycle, leading to heightened TCA flux and excessive mitochondrial reactive oxygen species (mtROS) production. In addition, PCK2 loss reduces glutamine availability for glutathione (GSH) synthesis, resulting in a decrease of total glutathione level. The elevated mtROS and reduced GSH expose ASCs to overwhelming oxidative stress, culminating in cell apoptosis. Crucially, we found that the mitochondria-targeted antioxidant Mitoquinone (Mito-Q) can mitigate the detrimental effects of PCK2 deficiency in IgA ASCs, thereby alleviating colitis in mice. Our findings highlight PCK2 as a key player in IgA ASC survival and provide a potential new target for colitis treatment.

A bimetallic peroxidase-mimicking nanozyme with antifouling property for construction of sensor array to identify phosphoproteins and diagnose cancers.

Protein phosphorylation is a significant post-translational modification that plays a decisive role in the occurrence and development of diseases. However, the rapid and accurate identification of phosphoproteins remains challenging. Herein, a high-throughput sensor array has been constructed based on a magnetic bimetallic nanozyme (Fe3O4@ZNP@UiO-66) for the identification and discrimination of phosphoproteins. Attributing to the formation of Fe-Zr bimetallic dual active centers, the as-prepared Fe3O4@ZNP@UiO-66 exhibits enhanced peroxidase-mimicking catalytic activity, which promotes the electron transfer from Zr center to Fe(II)/Fe(III). The catalytic activity of Fe3O4@ZNP@UiO-66 can be selectively inhibited by phosphoproteins due to the strong interaction between phosphate groups and Zr centers, as well as the ultra-robust antifouling capability of zwitterionic dopamine nanoparticle (ZNP). Considering the diverse binding affinities between various proteins with the nanozyme, the catalytic activity of Fe3O4@ZNP@UiO-66 can be changed to various degree, leading to the different absorption responses at 420 nm in the hydrogen peroxide (H2O2) - 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) system. By simply extracting different absorbance intensities at various time points, a sensor array based on reaction kinetics for the discrimination of phosphoproteins from other proteins is constructed through linear discriminant analysis (LDA). Besides, the quantitative determination of phosphoproteins and identification of protein mixtures have been realized. Further, based on the differential level of phosphoproteins in cells, the differentiation of cancer cells from normal cells can also be implemented by utilizing the proposed sensor array, showing great potential in disease diagnosis.

A case report of classic galactosemia with a GALT gene variant and a literature review.

BACKGROUND: Galactosemia is an autosomal recessive disorder resulting from an enzyme defect in the galactose metabolic pathway. The most severe manifestation of classic galactosemia is caused by galactose-1-phosphate uridylyltransferase (GALT) deficiency, and this condition can be fatal during infancy if left untreated. It also may result in long-term complications in affected individuals. CASE PRESENTATION: This report describes a patient whose initial clinical symptoms were jaundice and liver dysfunction. The patient's liver and coagulation functions did not improve after multiple admissions and treatment with antibiotics, hepatoprotective and choleretic agents and blood transfusion. Genetic analysis revealed the presence of two variants in the GALT gene in the compound heterozygous state: c.377 + 2dup and c.368G > C (p.Arg123Pro). Currently, the variant locus (c.377 + 2dup) in the GALT gene has not been reported in the Human Gene Mutation Database (HGMD), while c.368G > C (p.Arg123Pro) has not been reported in the Genome Aggregation Database (GnomAD) nor the HGMD in East Asian population. We postulated that the two variants may contribute to the development of classical galactosemia. CONCLUSIONS: Applications of whole-exome sequencing to detect the two variants can improve the detection and early diagnosis of classical galactosemia and, more specifically, may identify individuals who are compound heterozygous with variants in the GALT gene. Variants in the GALT gene have a potential therapeutic significance for classical galactosemia.

Plant polysaccharide-derived edible film packaging for instant food: Rapid dissolution in hot water coupled with exceptional mechanical and barrier characteristics.

A comprehensive multiscale analysis was conducted to explore the effects of different ratios of these materials on its properties. The results show that KC played a crucial role in controlling solution viscosity and gel and sol temperatures. The dissolution time at high water temperatures primarily decreased with an increase in SA content. Higher KC and CS content increased tensile strength (TS) and elongation at break (ε), while also exhibiting better thermal stability. Water vapor transmission (WVT) and permeability (PV) initially decreased, then increased with the increase of SA and CS contents. Finally, an SA:KC:CS ratio of 1:3:2 showed optimal comprehensive properties, with a dissolution time of about 60.0 ± 3.8 s, TS of 23.80 ± 0.29 MPa, ε of 18.61 ± 0.34 %, WVT of 21.74 ± 0.62 g/m2·24h, and PV of 5.39 ± 0.17 meq/kg. Meanwhile, the SA:KC:CS edible food packaging only introduced minimal effects on food after dissolution, and the total bacterial count met regulatory standards.

Positive association between chlorinated paraffins and the risk of allergic diseases in children and adolescents.

Contaminants may induce immune response polarization, leading to immune diseases, such as allergic diseases. Evidence concerning the effects of chlorinated paraffins (CPs), an emerging persistent organic pollutant, on immune system is scarce, particularly for epidemiological evidence. This study explores the association between CPs exposure and allergic diseases (allergic rhinitis, atopic eczema, and allergic conjunctivitis) in children and adolescents in the Pearl River Delta (PRD) in China. Herein, 131,304 children and adolescents from primary and secondary schools in the PRD were included and completed the questionnaire survey. The particulate matter (PM) samples were collected in the PRD and the PM2.5-bound CP concentrations were analyzed. In the multivarious adjustment mixed effect model (MEM), an IQR increase in ∑CPs was significantly associated with allergic diseases (rhinitis, eczema, and conjunctivitis) with the estimated odds ratios (ORs) for 1.11 (95% CI: 1.10, 1.13), 1.17 (95% CI: 1.15, 1.19), and 1.82 (95% CI: 1.76, 1.88), respectively. Interaction analysis indicated that overweight and obese individuals might have greater risk. Similar effect estimates were observed in several sensitivity analyses. This study provided epidemiological evidence on the immunotoxicity of CPs. More studies to confirm our findings and investigate mechanisms are needed.

TFA-Promoted Cascade Sulfonylation/Rearrangement/Cyclization of 1,5-Diynols and Sodium Sulfinates to Construct Sulfonylated Benzo[b]fluorenes.

A novel conversion of 1,5-diynols into sulfonylated benzo[b]fluorenes is reported by a TFA-promoted cascade cyclization with sodium sulfinates under mild conditions. This strategy provides an efficient and practical approach for accessing various sulfonated benzo[b]fluorenes in moderate to excellent yields under metal-free conditions. On the basis of the control experimental results and density functional theory calculations, a possible cascade transformation mechanism consisting of the dehydration of propargylic alcohols, sulfonylation, allenylation, and Schmittel-type cyclization is proposed. It is worth noting that TFA played an important role in this cascade cyclization, which promoted C-SO2R bond cleavage in a propargylic sulfone intermediate to form allenyl sulfones, followed by Schmittel-type cyclization to give the target product.

New caffeoyl derivatives with potent DPPH radical scavenging activity from Elephantopus tomentosus.

Eight new caffeoyl derivatives, elephantomentosides A-H (1 - 8), together with ten known ones (9 - 18), were isolated from the whole plant of Elephantopos tomentosus L. Their structures were elucidated using detailed spectroscopic analysis. Structurally, compounds 1 - 8 are composed of ß-D-glucopyranose, and almost all of the substituent positions are at the C-1' and C-4' of glucopyranose. The anti-inflammatory and antioxidant activities of all isolated compounds were evaluated in vitro. Compounds 9-10, 13-15, and 17-18 exhibited significant DPPH scavenging capacity with IC50 values in the range of 10.01-25.07 µM, in comparison with Vc (IC50, 17.98 µM).

Is the suppression of CD36 a promising way for atherosclerosis therapy?

Atherosclerosis is the main underlying pathology of many cardiovascular diseases and is marked by plaque formation in the artery wall. It has posed a serious threat to the health of people all over the world. CD36 acts as a significant regulator of lipid homeostasis, which is closely associated with the onset and progression of atherosclerosis and may be a new therapeutic target. The abnormal overexpression of CD36 facilitates lipid accumulation, foam cell formation, inflammation, endothelial apoptosis, and thrombosis. Numerous natural products and lipid-lowering agents are found to target the suppression of CD36 or inhibit the upregulation of CD36 to prevent and treat atherosclerosis. Here, the structure, expression regulation and function of CD36 in atherosclerosis and its related pharmacological therapies are reviewed. This review highlights the importance of drugs targeting CD36 suppression in the treatment and prevention of atherosclerosis, in order to develop new therapeutic strategies and potential anti-atherosclerotic drugs both preclinically and clinically.

Antibacterial activities of coumarin-3-carboxylic acid against Acidovorax citrulli.

Coumarin-3-carboxylic acid (3-CCA), previously screened from natural coumarins, was found to possess strong antibacterial activity against Acidovorax citrulli (Ac). In order to further evaluate the activity of this compound against plant bacterial pathogens and explore its potential value as a bactericidal lead compound, the activity of 3-CCA against 14 plant pathogenic bacteria in vitro and in vivo was tested. Results showed that 3-CCA exhibited strong in vitro activities against Ac, Ralstonia solanacearum, Xanthomonas axonopodis pv. manihotis, X. oryzae pv. oryzae, and Dickeya zeae with EC50 values ranging from 26.64 µg/mL to 40.73 µg/mL. Pot experiment results showed that 3-CCA had powerful protective and curative effects against Ac. In addition, the protective efficiency of 3-CCA was almost equivalent to that of thiodiazole copper at the same concentration. The results of SEM and TEM observation and conductivity tests showed that 3-CCA disrupted the integrity of the cell membrane and inhibited polar flagella growth. Furthermore, 3-CCA resulted in reductions in motility and extracellular exopolysaccharide (EPS) production of Ac while inhibiting the biofilm formation of Ac. These findings indicate that 3-CCA could be a promising natural lead compound against plant bacterial pathogens to explore novel antibacterial agents.

[Therapeutic effect and mechanism of Mailuo Shutong Pills on posterior limb swelling caused by femur fracture in rats based on intestinal flora and intestinal metabolism].

This study aimed to investigate the protective effect and underlying mechanism of Mailuo Shutong Pills(MLST) on posterior limb swelling caused by femur fracture in rats. The rats were randomly divided into a sham operation group, a model group, a low-dose MLST group(1.8 g·kg~(-1)·d~(-1)), a high-dose MLST group(3.6 g·kg~(-1)·d~(-1)), and a positive drug group(60 mg·kg~(-1)·d~(-1) Maizhiling Tablets). The femur in the sham operation group was exposed and the wound was sutured, while the other four groups underwent mechanical damage to cause femur fracture. The rats were treated with corresponding drugs by gavage 7 days before modeling and 5 days after modeling, while those in the sham operation group and the model group were given an equivalent dose of distilled water by gavage. Hematoxylin-eosin(HE) staining was used to detect the pathological injury of the posterior limb muscle tissues in rats, and the degree of hind limb swelling was measured. The enzyme-linked immunosorbent assay(ELISA) kit was used to detect the expression levels of interleukin-6(IL-6), interleukin-1ß(IL-1ß), and tumor necrosis factor-α(TNF-α) in the serum of rats in each group. The activity of superoxide dismutase(SOD), malondialdehyde(MDA), catalase(CAT), and glutathione peroxidase(GSH-Px) in rat serum was also measured. Western blot was used to detect the protein expression levels of heme oxygenase 1(HO-1), NAD(P)H quinone oxidoreductase 1(NQO1), and nuclear transcription factor E2-related factor 2(Nrf2) in rat posterior limb muscle tissues. The changes in the intestinal flora and intestinal metabolites in rats were detected by 16S rDNA sequencing and ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS), respectively, to explore the underlying mechanism of MLST in treating posterior limb swelling caused by femur fracture in rats. Compared with the model group, MLST significantly improved the degree of posterior limb swelling in rats, reduced the levels of serum inflammatory factors, and alleviated oxidative stress injury. The HE staining results showed that the inflammatory infiltration in the posterior limb muscle tissues of rats in the MLST groups was significantly improved. Western blot results showed that MLST significantly increased the protein expression of HO-1, NQO1, and Nrf2 in rat posterior limb muscle tissues compared with the model group. The 16S rDNA sequencing results showed that MLST improved the disorder of intestinal flora in rats after femur fracture. The UPLC-MS/MS results showed that MLST significantly affected the bile acid biosynthesis and metabolism pathway in the intestine after femur fracture, and the Spearman analysis confirmed that the metabolite deoxycholic acid involved in bile acid biosynthesis was positively correlated with the abundance of Turicibacter. The metabolite cholic acid was positively correlated with the abundance of Papilibacter, Staphylococcus, and Intestinimonas. The metabolite lithocholic acid was positively correlated with Papilibacter and Intestinimonas. The above results indicated that MLST could protect against the posterior limb swelling caused by femur fracture in rats. This protective effect may be achieved by improving the pathological injury of the posterior limb muscle, reducing the expression levels of inflammatory and oxidative stress-related factors in serum, reducing the oxidative injury of the posterior limb muscle, improving intestinal flora, and balancing the biosynthesis of bile acids in the intestine.