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 reveal the molecular basis of knee osteoarthritis (KOA) with Yang deficiency and blood stasis syndrome by analyzing the gene expression profiles in synovial fluid and blood of KOA patients with this syndrome. METHODS: A total of 80 KOA patients were recruited from October 2022 to June 2024, including 40 cases in the non-Yang deficiency and blood stasis group (27 males and 13 females), with an average age of (61.75±3.45) years old;and 40 cases in the Yang deficiency and blood stasis group (22 males and 18 females), with an average age of (62.00±2.76) years old. The levels of body mass index (BMI), high-density lipoprotein (HDL), low-density lipoprotein (LDL), fibrinogen, total cholesterol, and D-dimer were recorded and summarized. Blood and synovial fluid samples from patients were collected for gene expression profile microarray sequencing, and then PCR and immunohistochemistry were used for clinical verification on the patients' synovial fluid and cartilage samples. RESULTS: Logistic regression analysis showed that compared with KOA patients with non-Yang deficiency and blood stasis syndrome, those with Yang deficiency and blood stasis syndrome had increased BMI, LDL, fibrinogen, total cholesterol, and D-dimer, and decreased HDL, with a clear correlation between the two groups. There were 562 differential genes in the blood, among which 322 were up-regulated and 240 were down-regulated;755 differential genes were found in the synovial fluid, with 350 up-regulated and 405 down-regulated. KEGG signaling pathway analysis of synovial fluid revealed changes in lipid metabolism-related pathways, including cholesterol metabolism, fatty acid metabolism, and PPARG signaling pathway. Analysis of the involved differential genes identified 6 genes in synovial fluid that were closely related to lipid metabolism, namely LRP1, LPL, ACOT6, TM6SF2, DGKK, and PPARG. Subsequently, PCR and immunohistochemical verification were performed using synovial fluid and cartilage samples, and the results were consistent with those of microarray sequencing. CONCLUSION This study explores the clinical and genomic correlation between traditional Chinese medicine syndromes and knee osteoarthritis from the perspective of lipid metabolism, and proves that abnormal lipid metabolism is closely related to KOA with Yang deficiency and blood stasis syndrome from both clinical and basic aspects.
Humans ; Male ; Female ; Middle Aged ; Synovial Fluid/metabolism* ; Osteoarthritis, Knee/metabolism* ; Yang Deficiency/complications* ; Aged

Aim To verify the mechanism of action of Carthami Flos-Lycopodii Herba in treating KOA carti-lage inflammation based on network pharmacology and in vitro and in vivo experiments.Methods The effec-tive ingredients of Carthami Flos-Lycopodii Herba were screened through the database,the core targets of"drug disease"were analyzed,and pathway enrichment analy-sis and molecular docking verification were conducted.Experimental verification:Primary chondrocytes were extracted from mice and divided into the control group,IL-1β group,treatment group,and treatment+TLR4 agonist group.CCK-8 method was used to screen the optimal intervention concentration of Carthami Flos-Ly-copodii Herba.ELISA was used to detect the content of inflammatory factors in chondrocytes.Western blot was employed to detect the protein expression related to cellular pathways.Subsequently,a KOA mouse model was constructed using the DMM method.After admin-istration,the knee joint injury of mice was evaluated u-sing safranin O-green staining.ELISA was used to de-tect the levels of inflammatory factors in serum.West-ern blot was employed to detect collagen Ⅱ,MMP13,Aggrecan,and apoptosis related protein expression in cartilage tissue.TUNEL staining was used to detect the apoptosis rate of cells.Results A total of 26 active ingredients of Carthami Flos-Lycopodii Herba were screened,as well as 123 potential targets for treating KOA.The enrichment analysis results indicated that it mainly involved mechanisms such as Toll like receptors and cell apoptosis.The experimental results showed that Carthami Flos-Lycopodii Herba alleviated the in-flammatory response of chondrocytes and affected the expression of pathway related proteins.Compared with KOA mice,safflower stretched muscle grass could im-prove cartilage damage and reduce the concentration of serum inflammatory factors,regulate the expression of collagen Ⅱ,MMP13,Aggrecan,and apoptosis related proteins in cartilage tissue,and reduce the fluorescence intensity of TUNEL staining in the tissue.Conclusions Carthami Flos-Lycopodii Herba can improve KOA cartilage inflammation,and its mechanism may be relat-ed to the TLR4/MyD88/NF-κB signaling pathway.

Aim To investigate the therapeutic effects of cinnamaldehyde on synovial lesions in mice with knee osteoarthritis(KOA)and its regulatory mecha-nism in the phagocytic function of synovial macropha-ges.Methods In the animal experiments,mouse ser-um and synovial tissue were extracted.HE staining was used to evaluate the inflammatory cell infiltration in the synovial tissue.ELISA was employed to detect the lev-els of inflammatory factors such as interleukins in the serum.Western blot was used to detect the expression of Ras homolog family member A(RhoA),Rho-associ-ated protein kinase 1(ROCK1),myosin light chain(MLC),and p-MLC proteins in the synovial tissue.RT-qPCR was utilized to detect the expression of in-flammatory factors and pathway-related mRNA in the synovial tissue.TUNEL staining was used to detect ap-optosis in the synovial tissue.In the cellular experi-ments,after the intervention,RAW267.4 cells were subjected to Western blot and RT-qPCR for the detec-tion of the aforementioned indicators,and confocal mi-croscopy was used to assess phagocytic function.Re-sults After cinnamaldehyde intervention,the synovial inflammatory infiltration was significantly reduced,the protein and mRNA expression of the RhoA/ROCK1/MLC signaling pathway was markedly downregulated,the fluorescence intensity of TUNEL staining signifi-cantly decreased,and the phagocytic function of macro-phages was enhanced.Conclusion Cinnamaldehyde can inhibit RhoA/Rock1/MLC signaling pathway,en-hance macrophage burial,improve synovial inflamma-tion,and delay the progression of KO A mice.

AIM To investigate the clinical effects of Supplemented Gegen Qinlian Decoction combined with acupuncture on patients with ulcerative colitis of Large Intestinal Dampness-heat Pattern.METHODS One hundred and twenty patients were randomly assigned into control group(60 cases)for 1-month administration of Pefikang Capsules and Mesalazine Sustained Release Granules,and observation group(60 cases)for 1-month administration of Supplemented Gegen Qinlian Decoction,acupuncture,Pefikang Capsules and Mesalazine Sustained Release Granules.The changes in clinical effects,symptom remission time,TCM syndrome scores,Geboes index,lesion activity index,Baron score,inflammatory factors(IL-6,IL-8,TNF-α),immune function indices(IgA,IgG,IgM),IBDQ score and recurrence rate were detected.RESULTS The observation group demonstrated higher total effective rate than the control group(P＜0.05),along with shorter symptom remission time(P＜0.05)and lower recurrence rate(P＜0.05).After the treatment,the two groups displayed decreased TCM syndrome scores,Geboes index,lesion activity index,Baron score,inflammatory factors,IgG,IgM(P＜0.05),and increased IBDQ score(P＜0.05),especially for the observation group(P＜0.05).CONCLUSION For the patients with ulcerative colitis of Large Intestinal Dampness-heat Pattern,Gegen Qinlian Decoction combined with acupuncture can improve clinical symptoms,promote disease recovery,enhance immune functions and life quality,and reduce recurrence rate.

Aim To investigate the therapeutic effects of cinnamaldehyde on synovial lesions in mice with knee osteoarthritis(KOA)and its regulatory mecha-nism in the phagocytic function of synovial macropha-ges.Methods In the animal experiments,mouse ser-um and synovial tissue were extracted.HE staining was used to evaluate the inflammatory cell infiltration in the synovial tissue.ELISA was employed to detect the lev-els of inflammatory factors such as interleukins in the serum.Western blot was used to detect the expression of Ras homolog family member A(RhoA),Rho-associ-ated protein kinase 1(ROCK1),myosin light chain(MLC),and p-MLC proteins in the synovial tissue.RT-qPCR was utilized to detect the expression of in-flammatory factors and pathway-related mRNA in the synovial tissue.TUNEL staining was used to detect ap-optosis in the synovial tissue.In the cellular experi-ments,after the intervention,RAW267.4 cells were subjected to Western blot and RT-qPCR for the detec-tion of the aforementioned indicators,and confocal mi-croscopy was used to assess phagocytic function.Re-sults After cinnamaldehyde intervention,the synovial inflammatory infiltration was significantly reduced,the protein and mRNA expression of the RhoA/ROCK1/MLC signaling pathway was markedly downregulated,the fluorescence intensity of TUNEL staining signifi-cantly decreased,and the phagocytic function of macro-phages was enhanced.Conclusion Cinnamaldehyde can inhibit RhoA/Rock1/MLC signaling pathway,en-hance macrophage burial,improve synovial inflamma-tion,and delay the progression of KO A mice.

AIM To investigate the clinical effects of Supplemented Gegen Qinlian Decoction combined with acupuncture on patients with ulcerative colitis of Large Intestinal Dampness-heat Pattern.METHODS One hundred and twenty patients were randomly assigned into control group(60 cases)for 1-month administration of Pefikang Capsules and Mesalazine Sustained Release Granules,and observation group(60 cases)for 1-month administration of Supplemented Gegen Qinlian Decoction,acupuncture,Pefikang Capsules and Mesalazine Sustained Release Granules.The changes in clinical effects,symptom remission time,TCM syndrome scores,Geboes index,lesion activity index,Baron score,inflammatory factors(IL-6,IL-8,TNF-α),immune function indices(IgA,IgG,IgM),IBDQ score and recurrence rate were detected.RESULTS The observation group demonstrated higher total effective rate than the control group(P＜0.05),along with shorter symptom remission time(P＜0.05)and lower recurrence rate(P＜0.05).After the treatment,the two groups displayed decreased TCM syndrome scores,Geboes index,lesion activity index,Baron score,inflammatory factors,IgG,IgM(P＜0.05),and increased IBDQ score(P＜0.05),especially for the observation group(P＜0.05).CONCLUSION For the patients with ulcerative colitis of Large Intestinal Dampness-heat Pattern,Gegen Qinlian Decoction combined with acupuncture can improve clinical symptoms,promote disease recovery,enhance immune functions and life quality,and reduce recurrence rate.

Aim To verify the mechanism of action of Carthami Flos-Lycopodii Herba in treating KOA carti-lage inflammation based on network pharmacology and in vitro and in vivo experiments.Methods The effec-tive ingredients of Carthami Flos-Lycopodii Herba were screened through the database,the core targets of"drug disease"were analyzed,and pathway enrichment analy-sis and molecular docking verification were conducted.Experimental verification:Primary chondrocytes were extracted from mice and divided into the control group,IL-1β group,treatment group,and treatment+TLR4 agonist group.CCK-8 method was used to screen the optimal intervention concentration of Carthami Flos-Ly-copodii Herba.ELISA was used to detect the content of inflammatory factors in chondrocytes.Western blot was employed to detect the protein expression related to cellular pathways.Subsequently,a KOA mouse model was constructed using the DMM method.After admin-istration,the knee joint injury of mice was evaluated u-sing safranin O-green staining.ELISA was used to de-tect the levels of inflammatory factors in serum.West-ern blot was employed to detect collagen Ⅱ,MMP13,Aggrecan,and apoptosis related protein expression in cartilage tissue.TUNEL staining was used to detect the apoptosis rate of cells.Results A total of 26 active ingredients of Carthami Flos-Lycopodii Herba were screened,as well as 123 potential targets for treating KOA.The enrichment analysis results indicated that it mainly involved mechanisms such as Toll like receptors and cell apoptosis.The experimental results showed that Carthami Flos-Lycopodii Herba alleviated the in-flammatory response of chondrocytes and affected the expression of pathway related proteins.Compared with KOA mice,safflower stretched muscle grass could im-prove cartilage damage and reduce the concentration of serum inflammatory factors,regulate the expression of collagen Ⅱ,MMP13,Aggrecan,and apoptosis related proteins in cartilage tissue,and reduce the fluorescence intensity of TUNEL staining in the tissue.Conclusions Carthami Flos-Lycopodii Herba can improve KOA cartilage inflammation,and its mechanism may be relat-ed to the TLR4/MyD88/NF-κB signaling pathway.