Chlorophenolic compounds are persistent hazardous pollutants whose removal is particularly challenging in cold environments due to reduced microbial and enzymatic activity. In this study, a cold-adapted 2,4-dichlorophenol hydroxylase (TfdB-JLU) was systematically investigated and engineered to enhance pollutant degradation efficiency at low temperatures. Comparative structural analysis with homologous enzymes revealed key features associated with cold adaptation, including reduced stabilizing interactions, increased internal cavities, and enhanced flexibility in loop regions proximal to the catalytic pocket. Molecular dynamics simulations further demonstrated that localized flexibility facilitates substrate accommodation and catalytic turnover under low-temperature conditions. Guided by these insights, a structure-based engineering strategy was implemented through targeted glycine substitutions to increase conformational adaptability. The engineered variants exhibited significantly improved catalytic performance at 4°C, with specific activities increased by up to 1.79-fold (0.82 U/mg) compared with the wild-type enzyme. Kinetic analysis revealed reduced Km and enhanced kcat, while thermodynamic evaluation indicated decreased activation free energy barriers, supporting improved catalytic efficiency at 4°C. Importantly, the engineered enzymes achieved markedly enhanced degradation of 2,4-dichlorophenol and related chlorophenolic compounds under low-temperature conditions. This work elucidates the structural determinants underlying cold adaptation of aromatic monooxygenases and demonstrates an effective strategy for improving enzymatic pollutant removal in cold environments. The engineered TfdB variants provide promising biocatalysts for low-temperature bioremediation of chlorophenolic contaminants.

The mucin-degrading gut commensal bacterium Akkermansia muciniphila has emerged as a promising probiotic due to its significant health-promoting effects, wherein its protein constituents mediate critical host-microbe crosstalk. Notably, Amuc_0119 represents an uncharacterized protein potentially with beneficial biological functions. In this study, we aimed to construct an expression system for recombinant Amuc_0119 to facilitate its structural and functional characterization. The coding sequence of Amuc_0119 was cloned into pET-28a(+) vector with an N-terminal 6xHis-tag and successfully transformed into E. coli BL21(DE3) competent cells. Protein expression was induced by 0.5 mmol/L IPTG overnight at 37 degrees C. SDS-PAGE analysis revealed successful expression of the 46 kDa recombinant protein, which was subsequently purified via Ni-NTA affinity chromatography with a purity of 92.08%. Western blot with anti-His antibodies confirmed the target protein identity, while quantitative BCA assay determined a final concentration of 818.44 mu g/mL. This study establishes the first efficient expression and purification protocol for Akkermansia muciniphila-derived Amuc_0119, providing essential tools for forthcoming structural studies and functional investigations for this bacterial protein.

The gut microbiota-derived protein Amuc_1100, a key outer membrane component of Akkermansia muciniphila, has emerged as a groundbreaking therapeutic agent with unique structural and functional properties. Amuc_1100 exerts multifaceted immune-metabolic effects through novel mechanisms, including modulation of TLR2/4 and JAK/STAT pathways. This review highlights its unique multi-component structure that enables synergistic biological activity, and its pharmacological properties, which underlies its ability to enhance intestinal barrier integrity, restore microbiota balance, and suppress systemic inflammation. Crucially, Amuc_1100 demonstrates unprecedented therapeutic versatility across both intestinal disorders (e.g., inflammatory bowel disease, antibiotic-associated diarrhea) and extraintestinal conditions-notably improving neuropsychiatric symptoms via gut-serotonin axis regulation, combating cancer through CD8+ T cell activation, and mitigating cardiotoxicity via gut-heart immune crosstalk. Emerging innovations in targeted delivery systems, including gut-retentive nano-formulations and engineered probiotic vectors, further amplify its clinical potential. We critically evaluate recent advances distinguishing Amuc_1100's mechanisms from live bacterial interventions. By synthesizing evidence from preclinical models, this work positions Amuc_1100 as a prototype for next-generation microbiome-derived therapeutics, bridging microbial ecology with precision medicine.

Lead exposure is a well-documented environmental neurotoxin that poses a persistent threat to brain development. Excessive lead accumulation in this region impairs cognitive function and induces neuronal damage, yet effective therapeutic interventions remain limited. Baicalin, a flavonoid compound derived from Scutellaria baicalensis, exhibits antioxidant and neuroprotective activity, but its efficacy against lead-induced neural injury has not been fully elucidated. Here, we established a subchronic lead exposure model in mice and administered baicalin orally following lead treatment. Cognitive function was assessed through spatial, recognition, and avoidance learning paradigms. Lead concentrations in blood and hippocampus, as well as hippocampal structural integrity, oxidative stress markers, apoptosis signals, and neuronal autophagy, were quantitatively analyzed. In vitro studies using HT22 cells further investigated the effects of baicalin on oxidative stress, mitochondrial function, and autophagy-related signaling pathways. Baicalin treatment significantly improved cognitive performance, reduced blood and hippocampal lead concentrations, preserved hippocampal morphology, and reestablished redox homeostasis. Baicalin reduced lipid peroxidation, suppressed neuronal apoptosis, and restored autophagic flux. Mechanistically, baicalin activated AMPK, inhibited mTOR phosphorylation, and promoted ULK1-mediated autophagy. These effects were abolished by pharmacological inhibition of AMPK, confirming the pivotal regulatory role of baicalin. Collectively, these findings demonstrate that baicalin mitigates lead-induced cognitive and neuronal impairments by modulating oxidative stress, apoptosis, and autophagy via the AMPK-mTOR-ULK1 signaling axis. These results support further investigation of baicalin as a candidate neuroprotective agent for managing heavy metal-associated neurodevelopmental disorders.

Akkermansia muciniphila (AKK) is a mucin-degrading gut symbiont with emerging probiotic potential. Among its carbohydrate-active enzymes, Amuc_0517, a glycoside hydrolase family 36 (GH36) protein, has been identified as a highly specific α-galactosidase. In this study, the Amuc_0517 gene was cloned into pET-28a(+), expressed in Escherichia coli BL21, and purified via Ni2+-NTA affinity chromatography. Bioinformatic analysis indicated the presence of a signal peptide and α-galactosidase domain. Enzyme assays confirmed its ability to cleave α-1,6-glycosidic bonds in pNPGal, with no detectable activity toward pNPGlu, and molecular dynamics simulations revealed stronger binding affinity and lower free energy with pNPGal, supporting its substrate specificity. Given that α-galactosidases are widely applied in the dairy industry to hydrolyze galactose-containing oligosaccharides in milk and whey, the biochemical features of Amuc_0517 suggest its potential as a novel biocatalyst for functional dairy processing and probiotic-enriched dairy product development.

Central nervous system (CNS) diseases exhibit high incidence rates, and the blood–brain barrier (BBB) poses a major obstacle to drug delivery. Conventional drug delivery methods not only show limited therapeutic efficacy but also cause significant side effects. Intranasal administration offers a new strategy for CNS therapy by bypassing the BBB through the unique nasal-brain pathway, while nanodrug delivery systems (NDDSs) can improve drug delivery efficiency. On this basis, biomimetic drug delivery systems (BDDSs) based on cell membrane structure have been developed. The combination of nanoparticles modified by cell membranes or cell membrane-derived vesicles with carriers such as hydrogels creates a drug delivery system that utilizes a unique transnasal-to-brain pathway, opening new avenues for treating CNS disorders. This paper systematically reviews the classification, characteristics, and preparation strategies of BDDSs, while analyzing the anatomical pathways and physiological mechanisms of nasal–cerebral delivery. Furthermore, it delves into the biogenesis mechanisms of extracellular vesicles (EVs) and bacterial extracellular vesicles (BEVs). For CNS disorders, including glioblastoma multiforme (GBM), ischemic stroke (IS), Alzheimer’s disease (AD), and Parkinson’s disease (PD), this paper presents diverse applications and challenges of BDDSs in nasal–cerebral delivery.

Nephrotoxicity remains a major adverse reaction of the anticancer drug cisplatin (CDDP) chemotherapy, which is an important risk factor for chronic renal disease. Ginsenoside Rh2 from Panax ginseng has been shown to protect against CDDP-induced nephrotoxicity in vivo, but its pharmacological effect on renal tubular epithelial cells is not clearly understood. This study examined the molecular mechanisms underlying the nephroprotective effects of Rh2 on CDDP-induced HK-2 cells and acute kidney injury (AKI) mice. As a result of Rh2 treatment, CDDP-induced HK-2 cells showed increased cell viability and reduced lactate dehydrogenase release. Moreover, Rh2 ameliorated CDDP-induced mitochondrial membrane potential, increased antioxidant enzyme activities, and reduced pro-inflammatory cytokine expression to reduce damage. Rh2 inhibited apoptosis and enhanced the antioxidant capacity of HK-2 cells by reducing proteins associated with endoplasmic reticulum (ER) stress, as well as by attenuating tunicamycin-induced ER stress. In addition, treatment of CDDP-induced AKI mice with Rh2 substantially reduced blood urea nitrogen and serum creatinine levels, attenuated histological damage of kidney. Further, Rh2 also improved kidney function by inhibiting ER stress to support in vitro findings. These results consistently demonstrated that Rh2 protects renal tubular epithelial cells from CDDP-induced nephrotoxicity and apoptosis by restoring ER homeostasis, which might suggest a therapeutic potential and providing new insights into AKI alternative therapies.

Inflammatory bowel disease (IBD) is a chronic gastrointestinal disease with intricate pathogenesis, and clinical treatment is still not ideal. The imbalance of gut microbiota is associated with IBD progression. Various probiotics have been used as functional foods for the prevention and treatment of IBD, but the specific mechanism is still not fully understood. Lactobacillus johnsonii (L. johnsonii) is a potential anti-inflammatory bacterium, and compared to other probiotic Lactobacillus species, its colonization in the gut of colitis patients is significantly reduced. In this study, we first found that dietary L. johnsonii exerts strong anti-inflammatory and antioxidant effects in colitis mice, and this beneficial effect is directly related to its derived extracellular vesicles (LJ-EVs). Further experimental results indicate that LJ-EVs effectively prevented colitis symptoms and modulated gut microbiota and metabolic pathways. Meanwhile, we have studied for the first time the protective effect of LJ-EVs on the intestinal barrier from the perspective of reducing oxidative stress. We found that LJ-EVs can be directly taken up by intestinal epithelial cells and activate the Nrf2/HO-1 antioxidant signaling pathway, reducing endotoxin damage to cells and maintaining intestinal barrier homeostasis, which cascades to alleviate intestinal inflammation response. This study reveals the mechanism of L. johnsonii in treating colitis and provides a new approach for the development of oral LJ-EVs for the treatment of colitis.

BackgroundThere are many causes of acute liver injury (ALI), such as alcohol, drugs, infection, and toxic materials, which have caused major health problems around the world. Among these causes, alcohol consumption induced liver injury is a common alcoholic liver disease, which can further lead to liver failure even liver cancer. A number of traditional Chinese medicine (TCM) and TCM derived compounds have been used in treating the liver-associated diseases and combination use of probiotics with TCM phytochemicals has attracted interests for enhanced biological effects.MethodsThis study investigated the hepatoprotective effect of TCM-probiotics complex (TCMPC) and its underlying mechanism for the treatment of ALI in mice. The TCMPC is composed of TCM phytochemicals puerarin, curcumin, ginsenosides, and 5 lactobacteria strains. We first established a mouse model of alcohol-induced ALI, then the therapeutic effects of TCMPC on alcohol-induced ALI were monitored. A series of measurements have been performed on antioxidation, anti-inflammation, and lipid metabolism regulation.ResultsThe results showed that TCMPC can reduce the level of liver injury biomarkers and regulate oxidative stress. Histopathological results indicated that TCMPC could ameliorate ALI in mice. In addition, it can also significantly reduce the production of inflammatory cytokines caused by ALI.ConclusionOur research has proved the therapeutic effect of TCMPC on alcohol-induced ALI. The potential mechanism of hepatoprotective effects of TCMPC may be related to its antioxidative and anti-inflammatory effects. Our research might provide a new way for liver disease treatment.

The present study presents the tertiary assembly of a POM, peptide, and biogenic amine, which is a concept to construct new hybrid bio-inorganic materials for antibacterial applications and will help to promote the development of antivirus agents in the future. To achieve this, a Eu-containing polyoxometalate (EuW10) was first co-assembled with a biogenic amine of spermine (Spm), which improved both the luminescence and antibacterial effect of EuW10. Further introduction of a basic peptide from HPV E6, GL-22, induced more extensive enhancements, both of them being attributed to the cooperation and synergistic effects between the constituents, particularly the adaptive responses of assembly to the bacterial microenvironment (BME). Further intrinsic mechanism investigations revealed in detail that the encapsulation of EuW10 in Spm and further GL-22 enhanced the uptake abilities of EuW10 in bacteria, which further improved the ROS generation in BME via the abundant H2O2 involved there and significantly promoted the antibacterial effects.

新型冠状病毒(SARS-CoV-2)疫情在全球范围内大暴发.目前出现了SARS-CoV-2变异体和与其他病毒合并感染的新问题,使得临床检测与诊断更加困难.文章综述了目前基于多重PCR技术检测SARS-CoV-2核酸的方法.多重PCR技术在核酸检测的应用中具有高效、准确、特异、成本低的特点,与测序技术、质谱技术等其他技术联用,为SARS-CoV-2变异体与其他病毒合并感染的检测提供了新思路.

We successfully developed an antimicrobial assembly (Mo154/TK-14) using molybdenum-polyoxometalate and a positively charged peptide of TK-14. It was characterized and assayed using zeta-potential, dynamic light scattering (DLS), and TEM measurements. The Mo154/TK-14 assembly showed an enhanced 808 nm absorption and, therefore, improved the photothermal conversion efficiency of Mo154 (30.3%) to 38.6%. Consequently, in comparison to 5 μM Mo154 without irradiation, both the biofilm formation and bacterial viability of S. aureus were 24.6% and 20.2%, respectively, for the Mo154/TK-14 assembly; the biofilm formation and bacterial viability were further decreased to 7.7% and 4.4% under 808 nm irradiation, respectively. Therefore, the Mo154/TK-14 assembly reflects convincing antibacterial properties compared to Mo154. This is due to the synergistic effect between the peptide-binding enhanced 808 nm absorption and the improved PTT properties. The antimicrobial assembly offers a novel strategy for the rational design of light-responsive antibacterial materials.

COVID-19, a pandemic caused by the virus SARS-CoV-2, has spread globally, necessitating the search for antiviral compounds. Transmembrane protease serine 2 (TMPRSS2) is a cell surface protease that plays an essential role in SARS-CoV-2 infection. Therefore, researchers are searching for TMPRSS2 inhibitors that can be used for the treatment of COVID-19. As such, in this study, based on the crystal structure, we targeted the active site of TMPRSS2 for virtual screening of compounds in the FDA database. Then, we screened lumacaftor and ergotamine, which showed strong binding ability, using 100 ns molecular dynamics simulations to study the stability of the protein–ligand binding process, the flexibility of amino acid residues, and the formation of hydrogen bonds. Subsequently, we calculated the binding free energy of the protein–ligand complex by the MM-PBSA method. The results show that lumacaftor and ergotamine interact with residues around the TMPRSS2 active site, and reached equilibrium in the 100 ns molecular dynamics simulations. We think that lumacaftor and ergotamine, which we screened through in silico studies, can effectively inhibit the activity of TMPRSS2. Our findings provide a basis for subsequent in vitro experiments, having important implications for the development of effective anti-COVID-19 drugs.

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by recurrent gastrointestinal inflammation caused by abnormal immune response, and patients usually have intestinal flora imbalance. At present, the pathogenesis of UC is not well understood, and it appears that there is chronic activation of the immune and inflammatory cascade in genetically susceptible individuals. Some food supplements such as specific peptides and probiotics have been investigated and shown the potential for the treatment of UC. The purpose of this study is to investigate the therapeutic effect and potential mechanism of tetrapeptide from maize (TPM) and probiotic treatment on dextran sulfate sodium (DSS)-induced UC in C57BL/6J mice. Our results indicated that the therapeutic effects of TPM and probiotics are positively associated with a reduction in pro-inflammatory cytokine levels and restoration of the gut microbiota. Treatment with TPM or probiotics effectively alleviated the adverse effects of UC, including weight loss, shortened colon length, and colon and kidney tissue damage in mice. Additionally, both TPM and probiotics significantly reduced pro-inflammatory cytokine levels and oxidative stress in UC mice, and the effect was more pronounced when both were used together. Moreover, co-treatment with TPM and probiotics increased the diversity of gut microbes in UC mice, reduced the ratio of Firmicutes to Bacteroidetes (F/B) and increased the abundance of bacterial species, including Muribaculaceae, Alistipes, Ligilactobacillus and Lactobacillus, and has been shown to be beneficial for a variety of pathological conditions.

The authors wish to make the following corrections to this paper [...].

Humans, throughout the life cycle, from birth to death, are accompanied by the presence of gut microbes. Environmental factors, lifestyle, age and other factors can affect the balance of intestinal microbiota and their impact on human health. A large amount of data show that dietary, prebiotics, antibiotics can regulate various diseases through gut microbes. In this review, we focus on the role of gut microbes in the development of metabolic, gastrointestinal, neurological, immune diseases and, cancer. We also discuss the interaction between gut microbes and the host with respect to their beneficial and harmful effects, including their metabolites, microbial enzymes, small molecules and inflammatory molecules. More specifically, we evaluate the potential ability of gut microbes to cure diseases through Fecal Microbial Transplantation (FMT), which is expected to become a new type of clinical strategy for the treatment of various diseases.

Transdermal drug delivery (TDD) has recently emerged as an effective alternative to oral and injection administration because of its less invasiveness, low rejection rate, and excellent ease of administration. TDD has made an important contribution to medical practice such as diabetes, hemorrhoids, arthritis, migraine, and schizophrenia treatment, but has yet to fully achieve its potential in the treatment of obesity. Obesity has reached epidemic proportions globally and posed a significant threat to human health. Various approaches, including oral and injection administration have widely been used in clinical setting for obesity treatment. However, these traditional options remain ineffective and inconvenient, and carry risks of adverse effects. Therefore, alternative and advanced drug delivery strategies with higher efficacy and less toxicity such as TDD are urgently required for obesity treatment. This review summarizes current TDD technology, and the main anti-obesity drug delivery system. This review also provides insights into various anti-obesity drugs under study with a focus on the recent developments of TDD system for enhanced anti-obesity drug delivery. Although most of presented studies stay in animal stage, the application of TDD in anti-obesity drugs would have a significant impact on bringing safe and effective therapies to obese patients in the future.

Akkermansia muciniphila can produce various mucin-degrading proteins. However, the functional characteristics of these proteins and their role in mucin degradation are unclear. Of the predicted protein-coding genes, Amuc_1434, which encodes for a hypothetical protein, is the focus in this study. A recombinant enzyme Amuc_1434 containing the 6× His-tag produced in Escherichia coli (hereinafter termed Amuc_1434*) was isolated to homogeneity and biochemically characterised. Results showed that the enzyme can hydrolyse hemoglobin with an activity of 17.21 U/μg. The optimal pH and temperature for hemoglobin hydrolysis of Amuc_1434* were found to be around 8.0 and 40 °C, respectively. Amuc_1434* is identified as a member of the aspartic protease family through the action of inhibitor pepstatin A. Amuc_1434* promotes the adhesion of colon cancer cell line LS174T, which can highly express Muc2. Significantly Amuc_1434* can degrade Muc2 of colon cancer cells. Amuc_1434 is mainly located in the colon of BALB/c mice. These results suggest that the presence of Amuc_1434 from Akkermansia muciniphila may be correlated with the restoration of gut barrier function by decreasing mucus layer thickness.

The gut microbiome functions like an endocrine organ, generating bioactive metabolites, enzymes or small molecules that can impact host physiology. Gut dysbacteriosis is associated with many intestinal diseases including (but not limited to) inflammatory bowel disease, primary sclerosing cholangitis-IBD, irritable bowel syndrome, chronic constipation, osmotic diarrhoea and colorectal cancer. The potential pathogenic mechanism of gut dysbacteriosis associated with intestinal diseases includes the alteration of composition of gut microbiota as well as the gut microbiota-derived signalling molecules. The many correlations between the latter and the susceptibility for intestinal diseases has placed a spotlight on the gut microbiome as a potential novel target for therapeutics. Currently, faecal microbial transplantation, dietary interventions, use of probiotics, prebiotics and drugs are the major therapeutic tools utilized to impact dysbacteriosis and associated intestinal diseases. In this review, we systematically summarized the role of intestinal microbiome in the occurrence and development of intestinal diseases. The potential mechanism of the complex interplay between gut dysbacteriosis and intestinal diseases, and the treatment methods are also highlighted.

Context Alcoholic liver disease, caused by abuse and consumption of alcohol, exhibits high morbidity and mortality. Boletus aereus Bull. (Boletaceae) (BA) shows antioxidant, anti-inflammatory and antimicrobial effects. Objectives To investigate the hepatoprotective effects of BA using an acute alcohol-induced hepatotoxicity mice model. Materials and methods The composition of BA fruit body was first systematically analyzed. Subsequently, a C57BL/6 mice model of acute alcohol-induced liver injury was established by intragastrically administration of alcohol, which was intragastrically received with BA powder at 200 mg/kg and 800 mg/kg for 2 weeks, 60 mg/kg silybin treatment was used as positive control group. By employing the pathological examination, ELISA, RT-PCR and western blot, the regulation of BA on oxidative stress signals was investigated. Results The LD50 of BA was much higher than 4 g/kg/p.o. In acute alcohol-damaged mice, BA reduced the levels of alanine aminotransferase (>18.3%) and aspartate aminotransferase (>27.6%) in liver, increased the activity of liver alcohol dehydrogenase (>35.0%) and serum acetaldehyde dehydrogenase (>18.9%). BA increased the activity of superoxide dismutase (>13.4%), glutathione peroxidase (>11.0%) and 800 mg/kg BA strongly reduced chemokine (C-X-C motif) ligand 13 (14.9%) and chitinase-3 like-1 protein (13.4%) in serum. BA reversed mRNA over-expression (>70%) and phosphor-stimulated expression (>45.0%) of an inhibitor of nuclear factor κ-B kinase (NF-κB, an inhibitor of nuclear factor κ-B α and nuclear factor κ-B in the liver. Conclusions BA is effective in ameliorating alcohol-induced liver injury through regulating oxidative stress-mediated NF-κB signalling, which provides a scientific basis for further research on its clinical applications.