Riboflavin-ultraviolet A (UVA) collagen cross-linking has not only achieved good clinical efficacy in the treatment of corneal diseases such as dilatation keratopathy, bullae keratopathy, infectious keratopathy, and in the combined treatment of corneal refractive surgeries, but also its efficacy and safety in scleral collagen cross-linking have been initially confirmed. To better promote the application of cross-linking in the clinical treatment of corneal and scleral diseases, exploring controllability and predictability of the surgical efficacy are both important for evaluating the surgical efficacy and personalized precision treatment. In this paper, the progress on the cross-linking depth of riboflavin-UVA collagen cross-linking, and its relationship with the cross-linking effect will be reviewed. It will provide the reference for further application of this procedure in ophthalmology clinics.
Riboflavin/pharmacology* ; Humans ; Collagen/radiation effects* ; Ultraviolet Rays ; Cross-Linking Reagents ; Corneal Diseases/drug therapy* ; Photosensitizing Agents/therapeutic use*

OBJECTIVES: The application of photodynamic therapy in solid tumors has attracted increasing attention in recent years, and the efficiency of photosensitizers is a crucial determinant of therapeutic efficacy. This study aims to evaluate the cytotoxic effects of a novel photosensitizer, PEG-MTPABZ-PyC, in photodynamic therapy against gastric cancer cells. METHODS: Gastric cancer MKN45 cells were treated with PEG-MTPABZ-PyC. A high-content live-cell imaging system was used to assess the cellular uptake kinetics and subcellular localization of the photosensitizer. The cytotoxic effects of PEG-MTPABZ-PyC-mediated photodynamic therapy were examined using the cell counting kit-8 (CCK-8) assay and flow cytometry, while the intrinsic cytotoxicity of the photosensitizer alone was verified by the CCK-8 assay. Intracellular reactive oxygen species (ROS) generation after photodynamic therapy was detected using 2'-7'-dichlorodihydrofluorescein diacetate (DCFH-DA). RESULTS: PEG-MTPABZ-PyC alone exhibited no cytotoxicity toward MKN45 cells, indicating excellent cytocompatibility. The compound efficiently entered cells within 6 hours and localized predominantly in lysosomes. Upon light irradiation, PEG-MTPABZ-PyC-mediated photodynamic therapy induced significant cytotoxicity compared with the control group (P<0.05) and generated abundant intracellular ROS. CONCLUSIONS The novel photosensitizer PEG-MTPABZ-PyC demonstrates potent photodynamic cytotoxicity against gastric cancer cells, showing promising potential for further development in gastric cancer photodynamic therapy.
Humans ; Stomach Neoplasms/drug therapy* ; Photochemotherapy/methods* ; Photosensitizing Agents/pharmacology* ; Cell Line, Tumor ; Polyethylene Glycols/chemistry* ; Reactive Oxygen Species/metabolism* ; Mesoporphyrins/pharmacology*

The probiotic strain Escherichia coli Nissle 1917 (EcN) with high biocompatibility and susceptibility to genetic modification is often applied in bacterial therapies for cancer. However, most studies have used plasmids as vectors to construct engineering strains from EcN. Plasmid-based expression systems suffer from genetic instability, and they need antibiotic selective pressure to maintain high copy number. This study aimed to employ EcN for synthesizing the photosensitizer 5-aminolevulinic acid (5-ALA). Firstly, the key genes of 5-ALA synthesis, hemA^M and hemL, were integrated into the EcN genome by the phage integration technique. Then, chemically inducible chromosomal evolution (CIChE) was adopted to increase the copy number of hemA^M and hemL and thus improved the stable synthesis of 5-ALA. The in vitro cell experiments verified that the constructed engineering strain can deliver stably synthesized 5-ALA to tumor cells and inhibit their growth. This study provided a basis for applying the engineering strains of EcN in the photodynamic therapy for tumors.
Escherichia coli/metabolism* ; Aminolevulinic Acid/metabolism* ; Photosensitizing Agents/pharmacology* ; Plasmids/genetics* ; Chromosomes, Bacterial/genetics* ; Genetic Engineering ; Humans ; Probiotics ; Photochemotherapy

Objective: To investigate the effects of low-dose photodynamic therapy on the proliferation, regulation, and secretion functions of human adipose mesenchymal stem cells (ADSCs) and the related mechanism, so as to explore a new method for the repair of chronic wounds. Methods: The experimental research methods were adopted. From February to April 2021, 10 patients (5 males and 5 females, aged 23 to 47 years) who underwent cutaneous surgery in the Department of Dermatology of the First Affiliated Hospital of Army Medical University (the Third Military Medical University) donated postoperative waste adipose tissue. The cells were extracted from the adipose tissue and the phenotype was identified. Three batches of ADSCs were taken, with each batch of cells being divided into normal control group with conventional culture only, photosensitizer alone group with conventional culture after being treated with Hemoporfin, irradiation alone group with conventional culture after being treated with red light irradiation, and photosensitizer+irradiation group with conventional culture after being treated with Hemoporfin and red light irradiation, with sample number of 3 in each group. At culture hour of 24 after the treatment of the first and second batches of cells, the ADSC proliferation level was evaluated by 5-ethynyl-2'-deoxyuridine staining method and the migration percentage of HaCaT cells cocultured with ADSCs was detected by Transwell experiment, respectively. On culture day of 7 after the treatment of the third batch of cells, the extracellular matrix protein expression of ADSCs was detected by immunofluorescence method. The ADSCs were divided into 0 min post-photodynamic therapy group, 15 min post-photodynamic therapy group, 30 min post-photodynamic therapy group, and 60 min post-photodynamic therapy group, with 3 wells in each group. Western blotting was used to detect the protein expressions and calculate the phosphorylated mammalian target of rapamycin complex (p-mTOR)/mammalian target of rapamycin (mTOR), phosphorylated p70 ribosomal protein S6 kinase (p-p70 S6K)/p70 ribosomal protein S6 kinase (p70 S6K) ratio at the corresponding time points after photodynamic therapy. Two batches of ADSCs were taken, and each batch was divided into normal control group, photodynamic therapy alone group, and photodynamic therapy+rapamycin group, with 3 wells in each group. At culture minute of 15 after the treatment, p-mTOR/mTOR and p-p70 S6K/p70 S6K ratios of cells from the first batch were calculated and detected as before. On culture day of 7 after the treatment, extracellular matrix protein expression of cells from the second batch was detected as before. Data were statistically analyzed with one-way analysis of variance and least significant difference test. Results: After 12 d of culture, the cells were verified as ADSCs. At culture hour of 24 after the treatment, the ADSC proliferation level ((4.0±1.0)% and (4.1±0.4)%, respectively) and HaCaT cell migration percentages (1.17±0.14 and 1.13±0.12, respectively) in photosensitizer alone group and irradiation alone group were similar to those of normal control group ((3.7±0.6)% and 1.00±0.16, respectively, P>0.05), and were significantly lower than those of photosensitizer+irradiation group ((34.2±7.0)% and 2.55±0.13, respectively, P<0.01). On culture day of 7 after the treatment, compared with those in normal control group, the expression of collagen Ⅲ in ADSCs of photosensitizer alone group was significantly increased (P<0.05), and the expressions of collagen Ⅰ and collagen Ⅲ in ADSCs of irradiation alone group were significantly increased (P<0.01). Compared with those in photosensitizer alone group and irradiation alone group, the expressions of collagen Ⅰ, collagen Ⅲ, and fibronectin of ADSCs in photosensitizer+irradiation group were significantly increased (P<0.01). Compared with those in 0 min post-photodynamic therapy group, the ratios of p-mTOR/mTOR and p-p70 S6K/p70 S6K of ADSCs in 15 min post-photodynamic therapy group were significantly increased (P<0.01), the ratios of p-p70 S6K/p70 S6K of ADSCs in 30 min post-photodynamic therapy group and 60 min post-photodynamic therapy group were both significantly increased (P<0.01). At culture minute of 15 after the treatment, compared with those in normal control group, the ratios of p-mTOR/mTOR and p-p70 S6K/p70 S6K of ADSCs in photodynamic therapy alone group were significantly increased (P<0.05 or P<0.01). Compared with those in photodynamic therapy alone group, the ratios of p-mTOR/mTOR and p-p70 S6K/p70 S6K of ADSCs in photodynamic therapy+rapamycin group were significantly decreased (P<0.05). On culture day of 7 after the treatment, compared with those in normal control group, the expressions of collagen Ⅰ, collagen Ⅲ, and fibronectin of ADSCs in photodynamic therapy alone group were significantly increased (P<0.01). Compared with those in photodynamic therapy alone group, the expressions of collagen Ⅰ, collagen Ⅲ, and fibronectin of ADSCs in photodynamic therapy+rapamycin group were significantly decreased (P<0.01). Conclusions: Low-dose photodynamic therapy can promote the proliferation of ADSCs, improve the ability of ADSCs to regulate the migration of HaCaT cells, and enhance the secretion of extracellular matrix protein by rapidly activating mTOR signaling pathway.
Adipose Tissue ; Female ; Fibronectins ; Humans ; Male ; Mesenchymal Stem Cells ; Photochemotherapy ; Photosensitizing Agents/pharmacology* ; Sirolimus/pharmacology* ; TOR Serine-Threonine Kinases

The effect of parasitic ions on the results of ultraviolet A (UVA) cross-linking in iontophoresis was still not clear. In this work, the porcine sclera was cross-linked by riboflavin lactate Ringer's solution (group A) and riboflavin normal saline (group B)
Animals ; Collagen ; Cross-Linking Reagents ; Ions ; Iontophoresis ; Permeability ; Photosensitizing Agents/pharmacology* ; Riboflavin ; Sclera ; Swine ; Ultraviolet Rays

Although 5-aminolevulinic acid (5-ALA)-mediated photodynamic therapy (PDT) has been demonstrated to be a novel and effective therapeutic modality for some human malignancies, its effect and mechanism on glioma are still controversial. Previous studies have reported that 5-ALA-PDT induced necrosis of C6 rat glioma cells in vitro. The aim of this study was to further investigate the effect and mechanism of 5-ALA-PDT on C6 gliomas implanted in rats in vivo. Twenty-four rats bearing similar size of subcutaneously implanted C6 rat glioma were randomly divided into 3 groups: receiving 5-ALA-PDT (group A), laser irradiation (group B), and mock procedures but without any treatment (group C), respectively. The growth, histology, microvessel density (MVD), and apoptosis of the grafts in each group were determined after the treatments. As compared with groups B and C, the volume of tumor grafts was significantly reduced (P<0.05), MVD was significantly decreased (P<0.001), and the cellular necrosis was obviously increased in group A. There was no significant difference in apoptosis among the three groups. The in vivo studies confirmed that 5-ALA-PDT may be an effective treatment for gliomas by inhibiting the tumor growth. The mechanism underlying may involve increasing the cellular necrosis but not inducing the cellular apoptosis, which may result from the destruction of the tumor microvessels.
Aminolevulinic Acid ; pharmacology ; therapeutic use ; Animals ; Brain Neoplasms ; blood supply ; drug therapy ; pathology ; Cell Line, Tumor ; Glioma ; blood supply ; drug therapy ; pathology ; Microvessels ; drug effects ; Photochemotherapy ; Photosensitizing Agents ; pharmacology ; therapeutic use ; Rats ; Rats, Wistar ; Xenograft Model Antitumor Assays

OBJECTIVETo investigate the effect of 8-aminolevulinic acid (ALA) photodynamic therapy (PDT) on the cell proliferation, apoptosis and collagen secretion in keloid fibroblasts and to provide the theoretical base for ALA-PDT treatment of keloids.

METHODSFibroblasts from keloid patients were cultured to the third generation in vitro and incubated in 0, 1, 3, 6, 9 mmol/L of δ-aminolevulinic acid for 3 h in the darkness. Then they were exposed to 635 nm wavelength red light ( 30 J/cm2 ) and continued incubation 24 h after irradiation. CCK-8 assay was used to detect proliferation inhibition rate of fibroblasts. The content of hydroxyproline was measured by colorimetric method. The expression of p-Akt and programmed cell death 4 ( PDCD4) were detected by Western blot.

RESULTSThe inhibition rate of keloid fibroblasts were respectively 0, (8.30 ± 1.01)%, (29.48 ± 3.27)%, (52.01 ± 5.34)%, (79.99 ± 5.85)% with the presence of difference concentrations (0, 1, 3, 6, 9 mmol/L) of ALA. The content of hydroxyproline were respectively (9.540 0 ± 0.352 42), (6.242 5 ± 0.224 85 ), (5.107 5 ± 0.534 88), (3.490 0 ± 0.623 48), (2.945 0 ± 0.514 10) μg/mg. The relative expression of p-Akt were respectively 1, 0.75 ± 0.12, 0.52 ± 0.14, 0.41 ± 0.18, 0.32 ± 0.09. The relative expression of PDCD4 were respectively 1, 1.18 ± 0.19, 1.51 ± 0.22, 0.15 ± 0.30, 2.44 ± 0.22. The difference was statistically significant when compared the group of 1, 3, 6, 9 mmol/L with 0 mmol/L (P < 0.05).

CONCLUSIONSIn concentration within the range of 1-9 mmol/L, ALA could inhibit the proliferation of fibroblasts significantly, promote fibroblasts apoptosis and reduce the content of hydroxyproline in a dose-dependent manner, indicating that 8-aminolevulinic acid photodynamic therapy may be a potential treatment for keloid.

Aminolevulinic Acid ; pharmacology ; Apoptosis ; drug effects ; Cell Culture Techniques ; Cell Proliferation ; drug effects ; Collagen ; secretion ; Fibroblasts ; cytology ; drug effects ; secretion ; Humans ; Keloid ; drug therapy ; pathology ; Light ; Photochemotherapy ; methods ; Photosensitizing Agents ; pharmacology

OBJECTIVE: To investigate the effect and potential mechanisms about apoptosis induction and migration suppression of photodynamic therapy with a new photosensitizer, 9-hydroxypheophorbide-α (9-HPbD), and diode laser on HN-3 human laryngeal squamous cancer cells. METHOD: The attached HN-3 cancer cells were photosesitized with 0.29 μg/ml and 0.59 μg/ml 9-HPbD for 6 h and irradiated by 664 nm diode laser for 15 min at an energy density of 2.0 J/cm for activating 9-HPbD. Wound healing assay and photographing was respectively performed immediately after laser irradiation. Photographing focusing on the same location was repeated 12 h, 24 h and 36 h after PDT and cells migration distance counted respectively. H2DCFDA staining was used to assess accumulation of reactive oxygen series (ROS) 1 h after PDT. MTT assay, Hoechst33342/PI double staining, western blotting were respectively performed to assess cellular viability, apoptosis and the expression of Enos, p-c-Jun, EGFR. RESULT: Phototoxicity and apoptosis on HN-3 cells induced by 9-HPbD-PDT was exhibited in a dose-related manner. Neither 9-HPbD alone nor laser alone was cytotoxic to HN-3 cells. Generation of ROS was initiated immediately after PDT. The apoptotic cells, marked with condensed/fragmented blue or pink nuclei, and up-regulated expression of eNOS, p-c-Jun were subsequently induced 24 h after PDT. Coupled with a down-regulated expression of EGFR, a photosensitizer dose-ralated cell migration suppression was initiated by PDT. After pretreatment of GSH or ascorbic acid, a kind of antioxidant, the efficacy of PDT-induced apoptosis and migration suppression was partially inhibited. CONCLUSION Activation of p-c-Jun, eNOS and down-regulated expression of EGFR may respectively involve in the apoptosis induction and cell migration suppression after 9-HPbD-PDT. Generation of ROS may play an important role in the course of apoptosis induction and migration suppression of HN-3 cells initiated by 9-HPbD-PDT.
Apoptosis ; Carcinoma, Squamous Cell ; pathology ; Cell Line, Tumor ; drug effects ; Cell Movement ; Cell Survival ; Chlorophyll ; analogs & derivatives ; pharmacology ; Head and Neck Neoplasms ; pathology ; Humans ; Laryngeal Neoplasms ; pathology ; Lasers ; Photochemotherapy ; Photosensitizing Agents ; pharmacology ; Squamous Cell Carcinoma of Head and Neck

In our screening for photosensitizers from natural resources, four alkaloids were isolated from Glycosmis pentaphylla by various chromatography techniques. Their structures were identified as glycoborinine (1), glybomine B (2), carbalexin A (3) and N-p-coumaroyltyramine (4) by spectral analysis. Their photoactivated antimicrobial activities were evaluated by thin-layer chromatography (TLC) agar overlay assay against Staphylococcus aureus and Bacillus subtilis. It was found that compounds 1 and 4 showed photo-activated antimicrobial activities. Meantime, photo-activated DNA binding activities of these compounds were also assessed by using a specially prepared 1.8 kb DNA fragment and restriction enzymes. Under UVA irradiation, compound 1 showed moderate inhibition on Nde I, Xba I, Nco I and Bcl I which have either 5'-TpA or 5'-ApT and trace or no inhibition on other restriction enzymes. It showed a similar inhibition pattern with the reference 8-methoxypsoralen. However, compounds 2-4 showed no inhibition against any of the restriction enzymes.
Anti-Bacterial Agents ; chemistry ; isolation & purification ; pharmacology ; Bacillus subtilis ; drug effects ; Carbazoles ; chemistry ; isolation & purification ; pharmacology ; Chromatography, Thin Layer ; Coumaric Acids ; chemistry ; isolation & purification ; pharmacology ; DNA Fragmentation ; DNA Restriction Enzymes ; metabolism ; Light ; Molecular Structure ; Photosensitizing Agents ; pharmacology ; Plants, Medicinal ; chemistry ; Protein Binding ; Rutaceae ; chemistry ; Staphylococcus aureus ; drug effects ; Ultraviolet Rays

The objective of this study was to investigate the effect of a novel Zinc phthalocyanine (ZnPcH(1)) based photodynamic therapy (PDT) on acute monocytic leukemia cell lines SHI-1 and its mechanism, so as to provide theory basis for bone marrow purging in vitro for patients with leukemia. The killing effect of ZnPcH(1)-PDT on SHI-1 cells were assessed by MTT method; the SHI-1 cell death patterns were analyzed by AO/EB fluorescence staining, TdT-mediated dUTP nick end labeling (TUNEL), DNA ploidy analysis, and Annexin V-FITC/PI double staining.Cell mixture was established by integrating SHI-1 cells with normal bone marrow MNC (by 1:100-1:10 000). Purging effect of ZnPcH(1)-PDT against SHI-1 mixed into normal MNC was assessed by analyzing the expression of fusion gene MLL/AF6 mRNA using nested RT-PCR. The results showed that ZnPcH(1)-PDT could effectively inhibit SHI-1 cell proliferation in dose-dependent manner, and ZnPcH(1)-PDT could induce cell apoptosis in time-dependent manner. 0.5 µmol/L ZnPcH(1)-PDT could completely photoinactivated kill SHI-1 cells in the simulated remission bone marrow. It concluded that ZnPcH(1)-PDT may be a effective and convenient promising purging technique for leukemia.
Apoptosis ; drug effects ; Bone Marrow Purging ; methods ; Cell Death ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Humans ; Indoles ; pharmacology ; therapeutic use ; Leukemia, Monocytic, Acute ; drug therapy ; pathology ; Organometallic Compounds ; pharmacology ; therapeutic use ; Photochemotherapy ; Photosensitizing Agents ; pharmacology ; therapeutic use