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.

Objective To explore the application value of serum cystatin C(CysC)and cluster of differentiation 147(CD147)in predicting restenosis after intracranial artery stenosis stenting(ICASS)in patients with acute ischemic stroke(AIS).Methods A total of 151 AIS patients who received ICASS were selected as the study group,and 112 healthy individuals who underwent physical examinations during the same period were chosen as the control group.The study group was further divided into the restenosis group(30 cases)and the non-stenosis group(121 cases)based on the restenosis status within 6 months after ICASS.The serum CysC levels of the subjects were detected by immunoturbidimetry,and the serum CD147 levels were measured by enzyme-linked immunosorbent assay.Multivariate Logistic regression analysis was conducted to identify factors influencing restenosis after ICASS in AIS patients.The receiver operating characteristic(ROC)curve was used to evaluate the application efficacy of serum CysC and CD147 levels in predicting restenosis after ICASS in AIS patients.Results Serum levels of CysC and CD147 were higher in the study group than those in the control group(P＜0.01).The proportion of patients with stenosis degree>75%and serum levels of CysC and CD147 were higher in the restenosis group than those in the non-stenosis group(P＜0.01).The degree of stenosis>75%and the increased serum levels of CysC and CD147 were risk factors for restenosis after ICASS in AIS patients(P＜0.01).ROC curve analysis showed that serum CysC and CD147 levels independently predicted the AUC of AIS patients with restenosis after ICASS were 0.845 and 0.850,respectively,and the combined predicted AUC was 0.942.The combined prediction efficiency was significantly better than that of single indicator prediction(P＜0.05).Conclusion The increased levels of serum CysC and CD147 in AIS patients are risk factors for restenosis after ICASS,and the combination of the two is more effective in predicting intracranial artery restenosis after ICASS in AIS patients.

Objective:To explore the prospective association between physical activity level and mor-tality risk in Chinese adults with chronic obstructive pulmonary disease(COPD).Methods:Based on the China Kadoorie Biobank(CKB)who had COPD at the baseline survey,this study employed the Cox proportional hazards regression model to estimate the prospective associations between the overall physical activity,different intensities(low-level,moderate-to-vigorous-level),and types(occupational,non-occupational)of physical activity level and the risks of all-cause and cause-specific mortality,such as vascular diseases,cancer,and respiratory diseases.Based on the quintiles of physical activity level,par-ticipants were divided into five groups(Q1-Q5),with the lowest quintile group(Q1)as the reference group.Hazard ratio(HR)and 95％confidence interval(95％CI)were calculated for the remaining.In our study,we also performed sensitivity and subgroup analyses,including age,gender,self-rated health status,severity of COPD,etc.Results:Among 33 588 COPD patients at the baseline survey,8 314(22.2％)deaths were documented during an average follow-up of(11.1±3.1)years.Negative linear associations between the overall physical activity level and mortality risk from all-cause,vascular,and respiratory diseases were observed(P trend for linear correlation being＜0.001,0.002,＜0.001).Compared with the lowest quintile group of total physical activity(Q1),the hazard ratios(HR)and 95％confidence intervals(CI)for all-cause mortality,vascular disease mortality,and respiratory disease mortality in the highest quintile group(Q5)were 0.77(0.70,0.85),0.77(0.65,0.91),and 0.58(0.48,0.71),respectively.The low-level and moderate-to-vigorous-level physical activity were nega-tively associated with all-cause mortality in the COPD patients(P trend for linear correlation:0.002,＜0.001,respectively).Compared with the lowest quintile group of low-intensity and moderate-to-vigorous intensity physical activity(Q1),the HRs(95％CI)for all-cause mortality in the highest quintile group(Q5)were 0.89(0.82,0.97)and 0.79(0.72,0.87),respectively.The occupational and non-occupational physical activity were also found to have a linear inverse association with all-cause mortality risk among the COPD patients(P trend＜0.001 and 0.015,respectively).Compared with the lowest quintile group of occupational and non-occupational physical activity(Q1),the HR(95％CI)for all-cause mortality in the highest quintile group(Q5)were 0.69(0.61,0.78)and 0.91(0.84,0.98),respectively.The associations between overall physical activity and all-cause mortality risk were stronger for patients aged 60 and above,female,and who reported poor health status(P for interaction:0.028,0.012,0.010).The protective effect of total physical activity was also applicable to the COPD patients of varying severity.Conclusion:Physical activity could reduce the mortality risk in a dose-response relationship among COPD patients,regardless of its intensity and type,especially among indi-viduals aged 60 and above,females,and those with poor self-report health status.

This study was aimed at understanding the prevalence and drug resistance status of Salmonella of waterfowl ori-gin in the Guangdong region in the past decade,to guide prevention and control efforts.The drug-sensitive paper slide method was used to conduct drug susceptibility testing on 314 waterfowl-originating Salmonella strains isolated from 238 waterfowl farms in the Guangdong region from 2013 to 2023.The isolated Salmonella strains were most resistant to penicillin,amoxicil-lin,cefradine,and cefazolin in the β-lactam group;sulphadoxine dimethylpyrimidine in the sulphonamide group;and tetracy-cline in the tetracycline group.The resistance rates ranged from 73.57％to 89.49％.The highest sensitivity was observed to amikacin,gentamicin,and kanamycin in the aminoglycoside group,and norfloxacin in the quinolone group,with susceptibility rates all exceeding 50％.The 280 strains of Salmonella showed multi-drug resistance to six classes of antimicrobial drugs and high resistance(as much as 60.83％)to five drug classes.Correlation analysis revealed the highest correlations for florfenicol with gentamicin,and for amoxicillin with penicillin(r=0.650 for both),followed by gentamicin with kanamycin(r=0.620).Salmonella resistance in waterfowl in Guangdong Province was generally severe and showed a complex pattern of drug resist-ance.Detection of waterfowl pathogens should be strengthened to prevent the spread of drug-resistant bacteria and support ra-tional use of antibiotics.This work provides a reference for Salmonella prevention and control in waterfowl farms.

This study was aimed at understanding the prevalence and drug resistance status of Salmonella of waterfowl ori-gin in the Guangdong region in the past decade,to guide prevention and control efforts.The drug-sensitive paper slide method was used to conduct drug susceptibility testing on 314 waterfowl-originating Salmonella strains isolated from 238 waterfowl farms in the Guangdong region from 2013 to 2023.The isolated Salmonella strains were most resistant to penicillin,amoxicil-lin,cefradine,and cefazolin in the β-lactam group;sulphadoxine dimethylpyrimidine in the sulphonamide group;and tetracy-cline in the tetracycline group.The resistance rates ranged from 73.57％to 89.49％.The highest sensitivity was observed to amikacin,gentamicin,and kanamycin in the aminoglycoside group,and norfloxacin in the quinolone group,with susceptibility rates all exceeding 50％.The 280 strains of Salmonella showed multi-drug resistance to six classes of antimicrobial drugs and high resistance(as much as 60.83％)to five drug classes.Correlation analysis revealed the highest correlations for florfenicol with gentamicin,and for amoxicillin with penicillin(r=0.650 for both),followed by gentamicin with kanamycin(r=0.620).Salmonella resistance in waterfowl in Guangdong Province was generally severe and showed a complex pattern of drug resist-ance.Detection of waterfowl pathogens should be strengthened to prevent the spread of drug-resistant bacteria and support ra-tional use of antibiotics.This work provides a reference for Salmonella prevention and control in waterfowl farms.

Objective To investigate the effect of cordyceps sinensis(CS)on the activation of fibroblasts through IL-6 trans-signaling pathway and its specific mechanism in the treatment of renal fibrosis.Methods Renal fibrosis mouse model was established by unilateral ischemia/reperfusion(UIR),and the mice were administered intragastrically CS,soluble glycoprotein 130 Fc(sgp130Fc)or Hyper-IL-6.Masson's trichrome staining was utilized to identify tubulointerstitial fibrosis.PAS staining was utilized to assess the extent of renal injury.Western blot was employed to analyze the expression levels of fibrosis markers[alpha-smooth muscle actin(α-SMA),fibronectin(FN)]and proteins associated with IL-6 trans-signaling pathway[phosphorylated signal transducer and activator of transcription 3(p-STAT3),soluble interleukin-6 receptor(sIL-6R)].The expression and localization of proteins were additionally detected by immunohistochemistry,immunofluorescence and qPCR.The effect of cordyceps sinensis extract cordycepin on IL-6 trans-signaling in fibroblasts was further investigated in vitro.Results The results from in vivo experiments showed that administration of CS during the chronic phase demonstrated a beneficial protective impact on inflammation and fibrosis in the affected kidney,and serum creatinine levels and collagen deposition were decreased.Western blot analysis revealed a decrease in the expression levels of α-SMA,FN,as well as IL-6 trans-signaling pathway protein p-STAT3,sIL-6R in the treatment group.Additionally,the mRNA expression levels of chemokines monocyte chemoattractant protein-1(MCP-1)and C-X-C motif chemokine ligand 12(CXCL12)were also decreased in the CS treatment group.Additionally,Hyper-IL-6 can partially counteract the therapeutic effects of CS.In vitro experiments further demonstrated that cordycepin inhibited the secretion of IL-6 from NRK-52E.Combined treatment of recombinant IL-6 and sIL-6R protein activated NRK-49F,leading to a significant increase in α-SMA,FN,and p-STAT3 expression levels.Cordycepin or sgp130Fc treatment significantly inhibited the proliferation of fibroblasts induced by IL-6 trans-signaling pathway.Conclusion CS can significantly reduce IL-6 secretion by renal tubular epithelial cells and inhibit the activation of IL-6 trans-signaling pathway in fibroblasts,thereby ameliorating renal interstitial fibrosis.

OBJECTIVE To explore the intervention mechanism of Shangke Lengtongtie on cold hyperalgesia in KOA mice based on the HMGB1/CXCL12/CXCR4 signaling axis.METHODS Monosodium iodoacetate(MIA)was used for the intra-articular injec-tion into the knee joint to establish mice model of knee osteoarthritis(KOA).Peripheral blood monocytes were extracted from mice,cultured,and then reinfused into the tail vein of the mice.Subsequently,in vivo animal imaging was used to observe the recruitment sites of these monocytes.The cold hyperalgesia threshold was measured at various time points in each group of mice.Hematoxylin and eosin(HE)staining was used to evaluate the level of synovial pathological changes.ELISA was employed to detect the expression of in-flammatory factors IL-1β,TNF-α,and pain mediators CGRP and Substance P in mouse serum.Western blot and qPCR methods were used to detect the protein and gene expression of cold hyperalgesia-related indicators such as TRPA1,TRPM8,HMGB1,CXCL12,CXCR4,Collagen Ⅰ,and Netrin-1 in synovial tissue,as well as DCC in dorsal root ganglia(DRG)tissue.RESULTS In vivo ima-ging showed that after the monocytes were reinfused into KOA mice,they were recruited to the knee joint area,with the HMGB1 group exhibiting a greater recruitment of circulating monocytes at the knee joint.Additionally,compared to the control group,the KOA group and HMGB1 group showed inflammatory pathological changes in the synovium,increased expression of serum inflammatory factors and pain mediators,reduced cold hyperalgesia threshold,and upregulated protein and gene expression of cold hyperalgesia-related indica-tors in synovial and DRG tissues.The changes were more significant in the HMGB1 group compared to the KOA group(P<0.05).Af-ter treatment with Shangke Lengtongtie or GL intervention,synovial inflammation was alleviated,serum inflammatory factors and pain mediators decreased,cold hyperalgesia threshold increased,and the upregulation of cold hyperalgesia-related indicator protein and gene expression levels was significantly reversed(P<0.05).CONCLUSION Shangke Lengtongtie exerts a beneficial effect on the mitigation of synovitis and cold hyperalgesia in KOA mice,a therapeutic mechanism that possibly mediated through the inhibition of the HMGB1/CXCL12/CXCR4 signaling axis.

Objective:To investigate the protective effect of achyranthes bidentata(AB)on sperm quality in mice with sper-matogenic disorder through the glycolytic metabolic pathway and its action mechanism.Methods:We equally randomized 40 Kun-ming mice into a normal control,a model control,a low-dose AB(3.5 g/kg)and a high-dose AB group(7.0 g/kg),and established the model of spermatogenic disorder in the latter three groups of mice by intraperitoneal injection of doxorubicin(30 mg/kg).Two days after modeling,we collected the testis and kidney tissues and blood samples from the mice for observation of the pathological changes in the testis tissue by HE staining,detection of perm motility with the sperm quality analyzer,examination of the apoptosis of testis cells by flow cytometry,measurement of the levels of testosterone(T),malondialdehyde(MDA),superoxide dismutase(SOD)and cata-lase(CAT)in the serum and testis tissue by ELISA,and determination of expressions of the key enzymes of glycolysis hexokinase Ⅱ(HK2),pyruvate kinase M2(PKM2),platelet phosphofructokinase(PFKP),lactate dehydrogenase A(LDHA)and the meiosis pro-teins REC8 and SCP3 by Western blot,and the mRNA expressions of glycolytic phosphofructokinase 1(PFK1),phosphoglycerate ki-nase 1(PGK1),tumor necrosis factor-α(TNF-α)and interleukin-1 β(IL-1β)by fluorescence quantitative PCR(FQ-PCR).Results:Compared with the model controls,the mice in the AB groups showed significant increases in the testis coefficient,kidney in-dex,sperm concentration,sperm motility,spermatogonia,primary spermatocytes,spermatids,sperm count and the serum T level(P＜0.05 orP＜0.01),but dramatic decreases in the apoptosis of testis cells and percentage of morphologically abnormal sperm(P＜0.01).Achyranthes bidentata also significantly elevated the levels of SOD and CAT,and down-regulated the mRNA expressions of MDA,TNF-α and IL-1β(P＜0.05 or P＜0.01),and up-regulated the protein expressions of HK2,PKM2,PFKP,LDHA,REC8 and SCP3,and expressions of the glycolysis key genes Pfk1 and Pgk1(P＜0.05 orP＜0.01).Conclusion:Achyranthes bidentata ameliorates doxorubicin-induced spermatogenic disorder in mice by regulating the glycolytic pathway and reducing oxidative stress and the expressions of inflammatory factors.

Objective:The aim of this study is to re-evaluate the systematic reviews and meta-analyses on statins for the treat-ment of erectile dysfunction(ED)and construct an umbrella review,thereby providing robust evidence-based for the clinical applica-tion of statins in ED treatment.Methods:A comprehensive computerized search was conducted across CNKI,Wanfang Database,VIP,WOS,Embase,PubMed,and Cochrane Library databases from their inception to September 12,2024,for all systematic reviews and meta-analyses addressing statin interventions in ED.The methodological quality,reporting quality,and evidence quality of the in-cluded studies were assessed and summarized using PRISMA 2020,AMSTAR 2,and GRADE systems.Results:Four systematic re-views and meta-analyses were included.According to the AMSTAR 2 evaluation,one paper was rated as low quality,while the remai-ning three were classified as very low quality.PRISMA 2020 evaluation results indicated that the average score of the four included studies was 29,with all being of medium quality but exhibiting partial deficiencies.The proportion of fully consistent items across the four studies ranged from 52.38％to 80.95％.GRADE system tool evaluation revealed 11 outcome indicators,of which only one was rated as intermediate evidence.The remainders were categorized as low or very low evidence,with no high-quality evidence identified.Conclusion:Statins demonstrate efficacy in treating ED.However,the current quality of relevant systematic reviews is suboptimal,with notable deficiencies in methodological,reporting,and evidential quality.Further high-quality studies are warranted to provide more reliable evidence-based medical guidance for clinical practice.