1.In Vitro and in vivo Component Analysis of Total Phenolic Acids from Gei Herba and Its Effect on Promoting Acute Wound Healing and Inhibiting Scar Formation
Xixian KONG ; Guanghuan TIAN ; Tong WU ; Shaowei HU ; Jie ZHAO ; Fuzhu PAN ; Jingtong LIU ; Yong DENG ; Yi OUYANG ; Hongwei WU
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(3):156-167
ObjectiveBased on ultra performance liquid chromatography-quadrupole-electrostatic field orbital trap high-resolution mass spectrometry(UPLC-Q-Orbitrap-MS), to identify the in vivo and in vitro chemical components of total phenolic acids in Gei Herba(TPAGH), and to clarify the pharmacological effects and potential mechanisms of the effective part in promoting acute wound healing and inhibiting scar formation. MethodsUPLC-Q-Orbitrap-MS was used to identify the chemical components of TPAGH and ingredients absorbed in vivo after topical administration. A total of 120 ICR mice were randomly divided into the model group, recombinant human epidermal growth factor(rhEGF) group(4 mg·kg-1), and low, medium, and high dose groups of TPAGH(3.5, 7, 14 mg·kg-1), with 24 mice in each group. A full-thickness skin excision model was constructed, and each administration group was coated with the drug at the wound site, and the model group was treated with an equal volume of normal saline, the treatment was continued for 30 days, during which 8 mice from each group were sacrificed on days 6, 12, and 30. The healing of the wounds in the mice was observed, and histopathological changes in the skin tissues were dynamically observed by hematoxylin-eosin(HE), Masson, and Sirius red staining, and enzyme-linked immunosorbent assay(ELISA) was used to dynamically measure the contents of interleukin-6(IL-6), tumor necrosis factor-α(TNF-α), vascular endothelial growth factor A(VEGFA), matrix metalloproteinase(MMP)-3 and MMP-9 in skin tissues. Network pharmacology was used to predict the targets related to the promotion of acute wound healing and the inhibition of scar formation by TPAGH, and molecular docking of key components and targets was performed. Gene Ontology(GO) biological process analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analysis were carried out for the related targets, so as to construct a network diagram of herbal material-compound-target-pathway-pharmacological effect-disease for further exploring its potential mechanisms. ResultsA total of 146 compounds were identified in TPAGH, including 28 phenylpropanoids, 31 tannins, 23 triterpenes, 49 flavonoids, and 15 others, and 16 prototype components were found in the serum of mice. Pharmacodynamic results showed that, compared with the model group, the TPAGH groups showed a significant increase in relative wound healing rate and relative scar inhibition rate(P<0.05), and the number of new capillaries, number of fibroblasts, number of new skin appendages, epidermal regeneration rate, collagen deposition ratio, and Ⅲ/Ⅰ collagen ratio in the tissue were significantly improved(P<0.05, 0.01), the levels of IL-6, TNF-α, MMP-3 and MMP-9 in the skin tissues were reduced to different degrees, while the level of VEGFA was increased. Network pharmacology analysis screened 10 core targets, including tumor protein 53(TP53), sarcoma receptor coactivator(SRC), protein kinase B(Akt)1, signal transducer and activator of transcription 3(STAT3), epidermal growth factor receptor(EGFR) and so on, participating in 75 signaling pathways such as advanced glycation end-products(AGE)-receptor for AGE(AGE/RAGE) signaling pathway, phosphatidylinositol 3-kinase(PI3K)/Akt signaling pathway, mitogen-activated protein kinase(MAPK) signaling pathway. Molecular docking confirmed that the key components genistein, geraniin, and casuariin had good binding ability to TP53, SRC, Akt1, STAT3 and EGFR. ConclusionThis study comprehensively reflects the chemical composition of TPAGH and the absorbed components after topical administration through UPLC-Q-Orbitrap-MS. TPAGH significantly regulates key indicators of skin healing and tissue reconstruction, thereby clarifying its role in promoting acute wound healing and inhibiting scar formation. By combining in vitro and in vivo component identification with network pharmacology, the study explores how key components may bind to targets such as TP53, Akt1 and EGFR, exerting therapeutic effects through related pathways such as immune inflammation and vascular regeneration.
2.Screening of biomarkers for fibromyalgia syndrome and analysis of immune infiltration
Yani LIU ; Jinghuan YANG ; Huihui LU ; Yufang YI ; Zhixiang LI ; Yangfu OU ; Jingli WU ; Bing WEI
Chinese Journal of Tissue Engineering Research 2025;29(5):1091-1100
BACKGROUND:Fibromyalgia syndrome,as a common rheumatic disease,is related to central sensitization and immune abnormalities.However,the specific mechanism has not been elucidated,and there is a lack of specific diagnostic markers.Exploring the possible pathogenesis of this disease has important clinical significance. OBJECTIVE:To screen the potential diagnostic marker genes of fibromyalgia syndrome and analyze the possible immune infiltration characteristics based on bioinformatics methods,such as weighted gene co-expression network analysis(WGCNA),and machine learning. METHODS:Gene expression profiles in peripheral serum of fibromyalgia syndrome patients and healthy controls were obtained from the gene expression omnibus(GEO)database.The differentially co-expressed genes were screened in the expression profile by differential analysis and WGCNA analysis.Least absolute shrinkage and selection operator(LASSO)and support vector machine-recursive feature elimination(SVM-RFE)machine learning algorithm were further used to identify hub biomarkers,and draw receiver operating characteristic curve(ROC)to evaluate the accuracy of diagnosing fibromyalgia syndrome.Finally,single sample gene set enrichment analysis(ssGSEA)and gene set enrichment analysis(GSEA)were used to evaluate the immune cell infiltration and pathway enrichment in patients with fibromyalgia syndrome. RESULTS AND CONCLUSION:Eight down-regulated differentially expressed genes(DEGs)were obtained after differential analysis of the GSE67311 dataset according to the conditions of log2|(FC)|>0 and P<0.05.After WGCNA analysis,497 genes were included in the module(MEdarkviolet)with the highest positive correlation(r=0.22,P=0.04),and 19 genes were included in the module(MEsalmon2)with the highest negative correlation(r=-0.41,P=6×10-5).After intersecting DEGs and the module genes of WGCNA,seven genes were obtained.Four genes were screened out by LASSO regression algorithm and five genes were screened out by SVM-RFE machine learning algorithm.After the intersection of the two,three core genes were identified,which were germinal center associated signaling and motility like,integrin beta-8,and carboxypeptidase A3.The areas under the ROC curve of the three core genes were 0.744,0.739,and 0.734,respectively,indicating that they have good diagnostic value and can be used as biomarkers for fibromyalgia syndrome.The results of immune infiltration analysis showed that memory B cells,CD56 bright NK cells,and mast cells were significantly down-regulated in patients with fibromyalgia syndrome compared with the control group(P<0.05),and were significantly positively correlated with the above three biomarkers(P<0.05).The enrichment analysis suggested that there were nine fibromyalgia syndrome enrichment pathways,mainly related to olfactory transduction pathway,neuroactive ligand-receptor interaction,and infection pathway.The above results showed that the occurrence and development of fibromyalgia syndrome are related to the involvement of multiple genes,abnormal immune regulation,and multiple pathways imbalance.However,the interactions between these genes and immune cells,as well as their relationships with various pathways need to be further investigated.
3.Comprehensive Application of AHP-CRITIC Hybrid Weighting Method, Grey Correlation Analysis and BP-ANN in Optimization of Extraction Process of Qizhi Prescription
Qun LAN ; Yi CHENG ; Zian LI ; Bingyu WU ; Jinyu WANG ; Dewen LIU ; Yan TONG
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(8):176-186
ObjectiveBased on analytic hierarchy process(AHP)-criteria importance through intercriteria correlation(CRITIC) hybrid weighting method, grey relational analysis and backpropagation artificial neural network(BP-ANN), to optimize the water extraction process of Qizhi prescription, so as to provide an experimental basis for optimization of the preparation process of this prescription and the establishment of quality standards. MethodsL9(34) orthogonal test was employed, and the AHP-CRITIC hybrid weighting method was utilized to determine the weight coefficients of the quality fractions of various components, including astragaloside Ⅳ, polygalaxanthone Ⅲ, calycosin-7-O-β-D-glucoside, tenuifolin, and 3,6′-disinapoylsucrose, as well as the dry extract yield. The comprehensive score of each factor level combination in the orthogonal test were calculated as evaluation indicator to select the optimal extraction process parameters. The effects of extraction times, extraction time, and solvent dosage on the aqueous extraction process of the formula were investigated through intuitive analysis, variance analysis, and grey relational analysis. Meanwhile, a BP-ANN model was established to reverse-predict the optimal extraction process parameters of Qizhi prescription, and the optimized process parameters were validated. ResultsThe weight coefficients of the five index components(astragaloside Ⅳ, tenuifolin, calycosin-7-O-β-D-glucoside, polygalaxanthone Ⅲ, and 3,6′-disinapoylsucrose) and dry extract yield were 25.7%, 20.82%, 16.41%, 12.45%, 15.96% and 8.67%, respectively. The optimized extraction process parameters were extracted 3 times with 8, 6, 6 times the amount of water, each time for 1 h. The network prediction results of BP-ANN test samples were consistent with the orthogonal test results, and the mean square error(MSE) of the predicted and measured values of the network was <1%. The water extraction process of Qizhi prescription analyzed and predicted by relevant mathematical models was stable and feasible, which could effectively improve the extraction efficiency of the active ingredients of Astragali Radix and Polygalae Radix, and the average comprehensive score of the validation test was 90.85 with the relative standard deviation(RSD) of 1.55%. ConclusionThis study establishes a water extraction process for compound Qizhi granules, and the optimized extraction process can effectively improve the extraction efficiency of active ingredients, which provides useful references for the optimization of preparation process and the establishment of quality standards for other clinical experience formulas.
4.Clinical study on the treatment of chronic atrophic gastritis with spleen and stomach weakness syndrome by Piwei Peiyuan Pill combined with moxibustion
Kairui WU ; Yu YE ; Bei PEI ; Biao SONG ; Yi ZHANG ; Tingting LI ; Qi YANG ; Yun LIU ; Xuejun LI
Journal of Beijing University of Traditional Chinese Medicine 2025;48(2):280-290
Objective:
To determine the clinical efficacy and mechanism of Piwei Peiyuan Pill (PPP) combined with moxibustion for treating patients with chronic atrophic gastritis (CAG) with spleen and stomach weakness syndrome.
Methods:
Ninety-six CAG patients with spleen and stomach weakness syndrome who met the inclusion and exclusion criteria were enrolled at the Department of Spleen and Stomach Diseases of the Second Affiliated Hospital of Anhui University of Chinese Medicine from June 2022 to December 2023. The patients were randomly divided into a control, a Chinese medicine, and a combined group using a random number table method, with 32 cases in each group (two cases per group were excluded). The control group was treated with rabeprazole combined with folic acid tablets (both thrice daily), the Chinese medicine group was treated with PPP (8 g, thrice daily), and the combined group was treated with moxa stick moxibustion (once daily) on the basis of the Chinese medicine group for 12 consecutive weeks. Gastric mucosa atrophy in the three groups was observed before and after treatment. The gastric mucosal pathological score was evaluated. The Patient Reported Outcome (PRO) scale was used to evaluate the patients′ physical and mental health status and quality of life.An enzyme-linked immunosorbent assay was used to detect serum tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-4, IL-10, IL-37, and transforming growth factor (TGF)-β levels in each group. Real-time fluorescence PCR was used to detect the relative expression levels of signal transducer and activator of transcription 3 (STAT3) and mammalian target of rapamycin (mTOR) mRNA in each group. Western blotting was used to detect the relative expression levels of proteins related to the STAT3/mTOR signaling pathway, and the adverse drug reactions and events were recorded and compared.
Results:
There was no statistical difference in age, gender, disease duration, family history of gastrointestinal tumors, alcohol consumption history, and body mass index among the three groups of patients.The total therapeutic efficacy rates of the control, Chinese medicine, and combined groups in treating gastric mucosal atrophy were 66.67% (20/30), 86.67% (26/30), and 90.00% (27/30), respectively (P<0.05). Compared to before treatment, the pathological and PRO scale scores of gastric mucosa in each group decreased after treatment, and TNF-α, IL-1β, IL-37, and TGF-β levels decreased. The relative STAT3 and mTOR mRNA expression levels, as well as the relative STAT3, p-STAT3, mTOR, and p-mTOR protein expression levels decreased (P<0.05), whereas the IL-4 and IL-10 levels increased (P<0.05). After treatment, compared to the control group, the pathological score of gastric mucosa, PRO scale score, TNF-α, IL-1β, IL-37, TGF-β content, relative STAT3 and mTOR mRNA expression levels, and relative STAT3, p-STAT3, mTOR, and p-mTOR protein expression levels in the Chinese medicine and combined groups after treatment were reduced (P<0.05), whereas the IL-4 and IL-10 levels increased (P<0.05). After treatment, compared to the Chinese medicine group, the combined group showed a decrease in relative STAT3, mTOR mRNA expression levels, and STAT3, p-STAT3, mTOR, and p-mTOR protein expression levels (P<0.05).
Conclusion
The combination of PPP and moxibustion may regulate the inflammatory mechanism of the body by inhibiting the abnormal activation of the STAT3/mTOR signaling pathway, upregulating related anti-inflammatory factor levels, downregulating pro-inflammatory factor expression, and increasing related repair factor expression, thereby promoting the recovery of atrophic gastric mucosa, reducing discomfort symptoms, and improving the physical and mental state of CAG patients with spleen and stomach weakness syndrome.
5.Study of adsorption of coated aldehyde oxy-starch on the indexes of renal failure
Qian WU ; Cai-fen WANG ; Ning-ning PENG ; Qin NIE ; Tian-fu LI ; Jian-yu LIU ; Xiang-yi SONG ; Jian LIU ; Su-ping WU ; Ji-wen ZHANG ; Li-xin SUN
Acta Pharmaceutica Sinica 2025;60(2):498-505
The accumulation of uremic toxins such as urea nitrogen, blood creatinine, and uric acid of patients with renal failure
6.Molecular epidemiological characterization of influenza A(H3N2) virus in Fengxian District, Shanghai, in the surveillance year of 2023
Hongwei ZHAO ; Lixin TAO ; Xiaohong XIE ; Yi HU ; Xue ZHAO ; Meihua LIU ; Qingyuan ZHANG ; Lijie LU ; Chen’an LIU ; Mei WU
Shanghai Journal of Preventive Medicine 2025;37(1):18-22
ObjectiveTo understand the epidemiological distribution and gene evolutionary variation of influenza A (H3N2) viruses in Fengxian District, Shanghai, in the surveillance year of 2023, and to provide a reference basis for influenza prevention and control. MethodsThe prevalence of influenza virus in Fengxian District in the 2023 influenza surveillance year (April 2023‒March 2024) was analyzed. The hemagglutinin (HA) gene, neuraminidase (NA) gene, and amino acid sequences of 75 strains of H3N2 influenza viruses were compared with the vaccine reference strain for similarity matching and phylogenetic evolutionary analysis, in addition to an analysis of gene characterization and variation. ResultsIn Fengxian District, there was a mixed epidemic of H3N2 and H1N1 in the spring of 2023, with H3N2 being the predominant subtype in the second half of the year, and Victoria B becoming the predominant subtype in the spring of 2024. A total of 75 influenza strains of H3N2 with HA and NA genes were distributed in the 3C.2a1b.2a.2a.2a.3a.1 and B.4 branches, with overall similarity to the reference strain of the 2024 vaccine higher than that of the reference strain of the 2022 and 2023 vaccine. Compared with the 2023 vaccine reference strain, three antigenic sites and one receptor binding site were changed in HA, with three glycosylation sites reduced and two glycosylation sites added; where as in NA seven antigenic sites and the 222nd resistance site changed with two glycosylation sites reduced. ConclusionThe risk of antigenic variation and drug resistance of H3N2 in this region is high, and it is necessary to strengthen the publicity and education on the 2024 influenza vaccine and long-term monitoring of influenza virus prevalence and variation levels.
7.Correlation between the expression of serum LCN2, CMKLR1 and CCL11 and the severity of disease in patients with type 2 diabetes mellitus and dry eye
Guoying LIU ; Jiangping HOU ; Huan WU ; Yi JIANG
International Eye Science 2025;25(5):813-818
AIM: To investigate the correlation between the expression of serum lipocalin 2(LCN2), chemokine like receptor 1(CMKLR1), and C-C motif chemokine ligand 11(CCL11)and the severity of disease in patients with type 2 diabetes mellitus(T2DM)and dry eye(DE).METHODS:A prospective selection of 97 patients(194 eyes)diagnosed with T2DM and DE at our hospital from May 2022 to May 2024 was made as the DE group, which was further divided into mild(47 cases, 94 eyes), moderate(34 cases, 68 eyes), and severe(16 cases, 32 eyes)subgroups based on the severity of dry eye. Additionally, 97 patients(194 eyes)of T2DM without DE were selected as non-DE group, and 97 healthy volunteers(194 eyes)who underwent physical examination during the same period were chosen as control group. Serum levels of LCN2, CMKLR1, and CCL11 were measured in all participants. Spearman correlation analysis was used to assess the relationship between serum levels of LCN2, CMKLR1, and CCL11 and the severity of DE in T2DM patients; multivariate Logistic analysis was used to analyze the factors affecting the severity of T2DM patients with DE. The receiver operating characteristic(ROC)curve was drawn to analyze the diagnostic value of serum LCN2, CMKLR1 and CCL11 levels for moderate to severe dry eye in T2DM patients.RESULTS: Serum levels of LCN2, CMKLR1, and CCL11 increased progressively from the control group to the non-DE group and then to the DE group(all P<0.05). Within the DE group, these levels also increased progressively from the mild to moderate and then to the severe subgroups(all P<0.05). Spearman correlation analysis showed that serum levels of LCN2, CMKLR1, and CCL11 were positively correlated with the severity of disease(rs=0.604, 0.591, 0.559, respectively; all P<0.05). Stepwise forward multivariate Logistic analysis showed that Schirmer's test(SⅠt), tear break-up time(BUT), serum levels of LCN2, CMKLR1 and CCL11 were the factors affecting the severity of T2DM patients with DE; ROC curve analysis indicated that the combined diagnosis of serum LCN2, CMKLR1, and CCL11 for the progression of T2DM with DE to moderate-to-severe stages had an area under curve(AUC)value of 0.896, which was significantly higher than that of individual diagnoses of LCN2, CMKLR1, and CCL11(Z=2.925, 2.704, 3.483, respectively; P=0.003, 0.007, <0.001).CONCLUSION: Serum LCN2, CMKLR1 and CCL11 levels are increased in T2DM patients with DE, and are positively correlated with the severity of DE. The combination of the three has a high diagnostic value for moderate to severe DE.
8.Development status analysis and suggestions of TCM pharmacists in Chinese public TCM hospitals
Baojuan XUE ; Ning WU ; Yang ZHAO ; Junshu GE ; Yi WANG ; Zheyuan LIU ; Zhaoheng YANG ; Ying SUN
China Pharmacy 2025;36(8):903-907
OBJECTIVE To understand the development status and existing problems of traditional Chinese medicine(TCM) pharmacists in public TCM hospitals in China, aiming to provide suggestions for the competent departments to formulate management policies for TCM pharmacists and promote the healthy development of TCM. METHODS The data on the number and professional titles of TCM pharmacists in public TCM hospitals in China from 2019 to 2023 were collected. Descriptive analysis was employed to analyze the number, distribution and professional titles of TCM pharmacists in public TCM hospitals across the country, and to measure the quantity shortfalls of the number of TCM pharmacists in these hospitals. RESULTS From 2019 to 2023, the number of TCM pharmacists in public TCM hospitals in China grew slowly, with an average annual growth rate of 2.56%. However, the proportion of TCM pharmacists to the total number of pharmacists in public TCM hospitals gradually decreased, with an average annual growth rate of -0.65%. In terms of hospital grades, the number of TCM pharmacists in tertiary public TCM hospitals showed positive growth, while those in secondary and primary public TCM hospitals showed negative growth. In terms of hospital types, the average annual growth rate of TCM pharmacists in TCM hospitals was 2.22%, in integrated Chinese and Western medicine hospitals it was 7.97%, and in ethnic minority medicine hospitals it was 2.74%. The development of TCM pharmacists in different provinces was uneven. The annual growth rate of TCM pharmacists in Guizhou exceeded 10%, while the growth rate in Hunan and Heilongjiang was negative. In 2023, the number of TCM pharmacists per thousand population in public TCM hospitals was 0.03, indicating a relatively low staffing level. The professional titles of TCM pharmacists in public TCM hospitals were mainly primary and E-mail:601907549@qq.com intermediate, with a total of 67.33%. According to the calculation that the proportion of TCM pharmacists to pharmacists was not less than 60%, public TCM hospitals and hospitals of integrated TCM and Western medicine should be reconfigured with TCM pharmacists 6 212 and 1 288 people, respectively. CONCLUSIONS The number of TCM pharmacists in public TCM hospitals is growing slowly, with insufficient staffing levels, relatively low professional titles, and uneven distribution and development across provinces. It is suggested that relevant competent departments strengthen policy guidance, increase the attention given by the state level to TCM pharmacists, strengthen the construction of the talent team for TCM pharmacists, improve the quality and optimize the allocation of TCM pharmacist talents in order to promote the high-quality development of TCM services.
9.Expression and clinical significance of TLR4 and NF-κB in conjunctival epithelial cells and tears of patients with dry eye
Guoying LIU ; Jiangping HOU ; Huan WU ; Yi JIANG
International Eye Science 2025;25(6):975-979
AIM: To investigate the expression and clinical diagnostic value of toll-like receptor 4(TLR4)and nuclear factor-κB(NF-κB)in conjunctival epithelial cells and tears of patients with dry eye.METHODS: From January 2023 to June 2024, 104 dry eye patients(104 eyes, disease group)who visited our hospital and 100 healthy individuals(100 eyes, control group)who underwent physical examination were selected. The changes of TLR4 and NF-κB in conjunctival epithelial cells and tears were analyzed. Pearson analysis was applied to analyze the correlation between TLR4 and NF-κB expression in conjunctival epithelial cells and tears. Logistic analysis was applied to analyze the factors that affected dry eye. ROC was applied to analyze the diagnostic value of TLR4 and NF-κB expression in conjunctival epithelial cells and tears for dry eye.RESULTS: The differences in the use of eye drops, tear film break-up time(BUT), Schirmer's test(SⅠt), tear film thickness(TFT), and corneal fluorescein staining(CFS)scores between the disease group and the control group were statistically significant(all P<0.01). The expression levels of TLR4 and NF-κB in conjunctival epithelial cells and tears in the disease group were significantly higher than those in the control group(all P<0.01). There was a positive correlation between TLR4 and NF-κB in conjunctival epithelial cells and tears(r=0.392, 0.348, all P<0.05). Frequent use of eye drops, CFS score, TLR4, and NF-κB were risk factors for dry eye(OR=2.153, 3.183, 1.578, 2.452, all P<0.05), while BUT, SⅠt, and TFT were protective factors for dry eye(OR=0.654, 0.755, 0.276, all P<0.05). The sensitivity, specificity, and AUC of TLR4 combined with NF-κB in conjunctival epithelial cells in the diagnosis of dry eye were 86.54%, 81.00%, and 0.889, respectively. The combination of TLR4 and NF-κB had higher diagnostic value for dry eye than uncombined diagnosis(Zcombination-TLR4=3.506, P=0.001; Zcombination-NF-κB=3.165, P=0.002). The sensitivity, specificity, and AUC of TLR4 combined with NF-κB in tears for diagnosing dry eye were 82.69%, 70.00%, and 0.818, respectively. The combination of TLR4 and NF-κB in tears had higher diagnostic value for dry eye than uncombined diagnosis(Zcombination-TLR4=3.117, P=0.002; Zcombination-NF-κB=2.363, P=0.018).CONCLUSION: The expression levels of TLR4 and NF-κB in conjunctival epithelial cells and tears of patients with dry eye are elevated. TLR4 and NF-κB are related to the development of dry eye, and that elevated levels of both are associated with an increased risk of dry eye disease. The combination of TLR4 and NF-κB has a certain diagnostic significance for dry eye.
10.The Mechanism of Blue Light in Inactivating Microorganisms and Its Applications in The Food and Medical Fields
Ruo-Hong BI ; Rong-Qian WU ; Yi LÜ ; Xiao-Fei LIU
Progress in Biochemistry and Biophysics 2025;52(5):1219-1228
Blue light inactivation technology, particularly at the 405 nm wavelength, has demonstrated distinct and multifaceted mechanisms of action against both Gram-positive and Gram-negative bacteria, offering a promising alternative to conventional antibiotic therapies. For Gram-positive pathogens such as Bacillus cereus, Listeria monocytogenes, and methicillin-resistant Staphylococcus aureus (MRSA), the bactericidal effects are primarily mediated by endogenous porphyrins (e.g., protoporphyrin III, coproporphyrin III, and uroporphyrin III), which exhibit strong absorption peaks between 400-430 nm. Upon irradiation, these porphyrins are photoexcited to generate cytotoxic reactive oxygen species (ROS), including singlet oxygen, hydroxyl radicals, and superoxide anions, which collectively induce oxidative damage to cellular components. Early studies by Endarko et al. revealed that (405±5) nm blue light at 185 J/cm² effectively inactivated L. monocytogenes without exogenous photosensitizers, supporting the hypothesis of intrinsic photosensitizer involvement. Subsequent work by Masson-Meyers et al. demonstrated that 405 nm light at 121 J/cm² suppressed MRSA growth by activating endogenous porphyrins, leading to ROS accumulation. Kim et al. further elucidated that ROS generated under 405 nm irradiation directly interact with unsaturated fatty acids in bacterial membranes, initiating lipid peroxidation. This process disrupts membrane fluidity, compromises structural integrity, and impairs membrane-bound proteins, ultimately causing cell death. In contrast, Gram-negative bacteria such as Salmonella, Escherichia coli, Helicobacter pylori, Pseudomonas aeruginosa, and Acinetobacter baumannii exhibit more complex inactivation pathways. While endogenous porphyrins remain central to ROS generation, studies reveal additional photodynamic contributors, including flavins (e.g., riboflavin) and bacterial pigments. For instance, H. pylori naturally accumulates protoporphyrin and coproporphyrin mixtures, enabling efficient 405 nm light-mediated inactivation without antibiotic resistance concerns. Kim et al. demonstrated that 405 nm light at 288 J/cm² inactivates Salmonella by inducing genomic DNA oxidation (e.g., 8-hydroxy-deoxyguanosine formation) and disrupting membrane functions, particularly efflux pumps and glucose uptake systems. Huang et al. highlighted the enhanced efficacy of pulsed 405 nm light over continuous irradiation for E. coli, attributing this to increased membrane damage and optimized ROS generation through frequency-dependent photodynamic effects. Environmental factors such as temperature, pH, and osmotic stress further modulate susceptibility, sublethal stress conditions (e.g., high salinity or acidic environments) weaken bacterial membranes, rendering cells more vulnerable to subsequent ROS-mediated damage. The 405 nm blue light inactivates drug-resistant Pseudomonas aeruginosa through endogenous porphyrins, pyocyanin, and pyoverdine, with the inactivation efficacy influenced by bacterial growth phase and culture medium composition. Intriguingly, repeated 405 nm exposure (20 cycles) failed to induce resistance in A. baumannii, with transient tolerance linked to transient overexpression of antioxidant enzymes (e.g., superoxide dismutase) or stress-response genes (e.g., oxyR). For Gram-positive bacteria, porphyrin abundance dictates sensitivity, whereas in Gram-negative species, membrane architecture and accessory pigments modulate outcomes. Critically, ROS-mediated damage is nonspecific, targeting DNA, proteins, and lipids simultaneously, thereby minimizing resistance evolution. The 405 nm blue light technology, as a non-chemical sterilization method, shows promise in medical and food industries. It enhances infection control through photodynamic therapy and disinfection, synergizing with red light for anti-inflammatory treatments (e.g., acne). In food processing, it effectively inactivates pathogens (e.g., E. coli, S. aureus) without altering food quality. Despite efficacy against multidrug-resistant A. baumannii, challenges include device standardization, limited penetration in complex materials, and optimization of photosensitizers/light parameters. Interdisciplinary research is needed to address these limitations and scale applications in healthcare, food safety, and environmental decontamination.


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