Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe²⁺), whereas clMagR favors ferric iron (Fe³⁺) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe²⁺-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe²⁺/Fe³⁺ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.

Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe²⁺), whereas clMagR favors ferric iron (Fe³⁺) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe²⁺-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe²⁺/Fe³⁺ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.

Depression is a widespread psychiatric disorder with complex pathogenesis and unsatisfactory therapeutic effects. As a native flavonoid, Isorhamnetin (ISO) has been deemed to exert neuroprotective effects by antioxidation and regulation of immunity. However, no reports of anti-depressed effect of ISO have yet been found. The present study was conducted to clarify the mechanism basis of anti-depressed effect of ISO utilizing behavioral, biochemical, molecular approaches in vitro and in vivo and bio-informatics analysis. The effects of ISO on depressed mice was investigated through the SPT and FST, and the lesions were examined by H&E staining. Besides, the inflammatory factor and indicator in kynurenine pathway were assessed through detection kits, and the microbiota were checked by 16sRNA. Molecular docking study was performed to investigate the target of ISO. Additionally, Western blot was used to test the activation of PI3K/AKT signaling pathway. The results indicated that ISO could enhance the sugar water preference of mice in SPT and reduce immobility time in FST. Further more, ISO suppressed peripheral and central inflammation, regulated the changes in kynurenine pathway and gut microbiota, inhibited activation of PI3K/AKT pathway, and presented good binding patterns with target proteins on PI3K/AKT signaling pathway. Collectively, these findings demonstrate that ISO alleviated depression-like behaviour by normalizing inflammation-induced dysregulation of the crosstalk between KP and gut microbiota disorder through regulated PI3K/AKT/NF-κB pathway.

Depression is a widespread psychiatric disorder with complex pathogenesis and unsatisfactory therapeutic effects. As a native flavonoid, Isorhamnetin (ISO) has been deemed to exert neuroprotective effects by antioxidation and regulation of immunity. However, no reports of anti-depressed effect of ISO have yet been found. The present study was conducted to clarify the mechanism basis of anti-depressed effect of ISO utilizing behavioral, biochemical, molecular approaches in vitro and in vivo and bio-informatics analysis. The effects of ISO on depressed mice was investigated through the SPT and FST, and the lesions were examined by H&E staining. Besides, the inflammatory factor and indicator in kynurenine pathway were assessed through detection kits, and the microbiota were checked by 16sRNA. Molecular docking study was performed to investigate the target of ISO. Additionally, Western blot was used to test the activation of PI3K/AKT signaling pathway. The results indicated that ISO could enhance the sugar water preference of mice in SPT and reduce immobility time in FST. Further more, ISO suppressed peripheral and central inflammation, regulated the changes in kynurenine pathway and gut microbiota, inhibited activation of PI3K/AKT pathway, and presented good binding patterns with target proteins on PI3K/AKT signaling pathway. Collectively, these findings demonstrate that ISO alleviated depression-like behaviour by normalizing inflammation-induced dysregulation of the crosstalk between KP and gut microbiota disorder through regulated PI3K/AKT/NF-κB pathway.

Aortic regurgitation and mitral regurgitation are more common in elderly heart valve disease,and both may be present in some patients.Severe aortic regurgitation complicated with severe mitral regurgitation often requires surgical valve replacement,but in patients at high risk of surgery,the risk of perioperative mortality is significantly increased.Therefore,for such patients,minimally invasive interventions can significantly improve long-term patient outcomes while reducing surgical risk.This article report a case of transcatheter aortic valve replacement combined with transcatheter edge-to-edge repair in the treatment of severe aortic regurgitation combined with mitral valve prolapse,in order to explore new treatment ideas for similar cases.

The xylitol dehydrogenase(XDH)is a crucial enzyme involved in the xylose utilization in pentose-catabolizing yeasts and fungi.In addition to producing xylulose,XDH can also be employed to develop a biosensor for monitoring xylitol concentration.In this study,the gene encoding the thermophilic fungus Talaromyces emersonii XDH(TeXDH)was heterologously expressed in Escherichia coli BL21(DE3)at 16 ℃ in the soluble form.Recombinant TeXDH with high purity was purified by using a Ni-NTA affinity column.Size-exclusion chromatography and SDS-PAGE analysis demonstrated that the puri-fied recombinant TeXDH exists as a native trimer with a molecular mass of approximately 116 kD,and is composed of three identical subunits,each with a molecular weight of around 39 kD.The TeXDH strictly preferred NAD+as a coenzyme to NADP+.The optimal temperature and pH of the TeXDH were 40 ℃and 10.0,respectively.After EDTA treatment,the enzyme activity of TeXDH decreased to 43.26％of the initial enzyme activity,while the divalent metal ions Mg2+or Ca2+could recover the enzyme activity of TeXDH,reaching 103.32％and 110.69％of the initial enzyme activity,respectively,making them the optimal divalent metal ion cofactors for TeXDH enzyme.However,the divalent metal ions of Mn2+,Ni2+,Cu2+,Zn2+,Co2+,and Cd2+significantly inhibited the activity of TeXDH.ICP-MS and molecular doc-king studies revealed that 1 mol/L of TeXDH bound 2 mol/L Zn2+ions and 1 mol/L Mg2+ion.Further-more,TeXDH exhibited a high specificity for xylitol,laying the foundation for the development of future xylitol biosensors.

Aortic regurgitation and mitral regurgitation are more common in elderly heart valve disease,and both may be present in some patients.Severe aortic regurgitation complicated with severe mitral regurgitation often requires surgical valve replacement,but in patients at high risk of surgery,the risk of perioperative mortality is significantly increased.Therefore,for such patients,minimally invasive interventions can significantly improve long-term patient outcomes while reducing surgical risk.This article report a case of transcatheter aortic valve replacement combined with transcatheter edge-to-edge repair in the treatment of severe aortic regurgitation combined with mitral valve prolapse,in order to explore new treatment ideas for similar cases.

Objective:To explore the effects and mechanisms of Shen-su-yin (SSY) on acute lung injury (ALI) in rats based on untargeted Metabolomics, network pharmacology, and experimental verification.Methods:Untargeted Metabolomics was performed to detect the ingredients of SSY by using ultra-high performance liquid chromatography-Q-exactive orbitrap mass spectrum, and the active ingredients were screened from the detected ingredients. Common targets of the active ingredient targets and ALI targets were utilized to screen hub targets to perform gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis. Then, key hub targets were selected from the hub targets, and the active ingredients-hub targets network was built to screen core ingredients. Subsequently, molecular docking was performed between the key hub targets and the core ingredients. 48 rats were randomly and equally divided into 4 groups by using a random number table: normal control group, lipopolysaccharide-induced ALI group, ALI+SSY group, and ALI+dexamethasone group. 24 hours after lipopolysaccharide induction, the levels of respiratory rate, blood lactate, lung wet/dry weight ratio, ALI score, inflammatory factors of bronchoalveolar lavage fluid, and oxidative stress mediators of lung tissue in each group were evaluated, and the expression of phosphatidylinositol 3-kinase (PI3K)-protein kinase B (AKT)-glycogen synthase kinase (GSK) 3β-nuclear factor erythroid 2-related factor 2 (Nrf2)/nuclear factor (NF)-κB signaling pathway was also detected by using Western blot. Finally, one-way analysis of variance, Welch test, or Kruskal-Wallis H test was used to compare data differences among groups. Results:A total of 415 ingredients were detected from the SSY. 66 of the detected ingredients were identified as active ingredients, and 10 of them were selected as core ingredients. The number of common targets, hub targets, and key hub targets was 337, 50, and 10, respectively. Total of 285 biological processes, 32 cellular components, and 51 molecular functions were enriched though GO analysis, and 148 cell signaling pathways such as pathways in cancer and PI3K-AKT signaling pathway were enriched though KEGG analysis. Molecular docking studies revealed that all binding energies between the 10 key hub targets and the 10 core ingredients were less than -5 kcal/mol. Compared with the ALI group, the levels of the respiratory rate, blood lactate, and lung wet/dry weight ratio in ALI+SSY group were significantly decreased (all P<0.01), and the level of ALI score showed a downward trend, but the difference was not statistically significant ( P>0.05). In addition, the levels of interleukin-6, interleukin-1β, and tumor necrosis factor-α in bronchoalveolar lavage fluid and the levels of malondialdehyde, protein carbonyl, and 8-hydroxy-2-deoxyguanosine in lung tissue of rats in ALI+SSY group were significantly decreased in comparison with those in ALI group (all P<0.01). Moreover, compared with the ALI group, the phosphorylation levels of PI3K p85α, AKT1, and GSK3β and the expression level of Nrf2 in lung tissue of ALI+SSY group were significantly up-regulated (PI3K p85α phosphorylation and AKT1 phosphorylation, P<0.01; GSK3β phosphorylation and Nrf2, P<0.05), while the phosphorylation level of NF-κB p65 was significantly down-regulated ( P<0.01). Conclusions:Active ingredients detected from SSY via untargeted Metabolomics can inhibit oxidative stress and inflammation in ALI rats by regulating the PI3K-AKT-GSK3β-Nrf2/NF-κB signaling pathway, thereby alleviating lung lesions.