Photochemistry and Photobiology最新文献

Recently (Photochem Photobiol. 2023;100:1277-1289. doi:10.1111/php.13898), we described the anti-Kasha effect in tribenzo-6H-1,4-diazepinoporphyrazins with C_2v symmetry, where the ultrafast spin changes successfully compete with the internal conversion. In this study, we show the presence of this effect in 2 (3),9 (10),16(17),23(24)-tetra-tert-butyl-29H,31H-phthalocyanine (1) and 1,4-di-[2-(2-methoxyethoxy)ethoxy]-29H,31H-phthalocyanine (2), which also possess reduced molecular symmetry and do not bear 6H-1,4-diazepine fragments. The anti-Kasha effect in 1 and 2 supplemented by Mg(II) tribenzo-6H-1,4-diazepinoporphyrazinates 3 and 4 exhibits a close-to-linear dependence on energy gap value between the zero vibrational levels of two lowest singlet excited states S₁ ⁰ and S₂ ⁰ (these states are degenerate in D_4h symmetry) and enhances with increase. The theoretical kinetic model of excited state dynamics, which takes into account the observed effects and follows Fermi's golden rule, predicts the presence of an additional excited state with enhanced spin-orbit coupling compared to S₁ ⁰, S₂ ⁰ and the corresponding triplet states, which is not predicted by TDDFT calculations in the Born-Oppenheimer approximation. The combination of the above indicates that the key role in the observed anti-Kasha effect and the mechanism of dissipation of the excited state in porphyrazines and their analogs is played by vibronic excited states, which requires theoretical research methods beyond the Born-Oppenheimer approximation.

Skin serves as our outermost barrier, protecting our bodies from various environmental damages. Increasing research has revealed that UVB is a primary factor for extrinsic aging. This study explored the role of a novel microcapsule composite Spherulites Peony Superior Retinol (SPSR) on skin damage induced by UVB. SPSR exhibited a capacity to eliminate UVB-induced ROS. By measurement of cyclobutane pyrimidine dimers (CPD) and comet assay, the results implied that SPSR mitigates DNA damage from oxidative damage caused by UVB. In addition, UVB radiation typically leads to an increase in inflammatory factors within the skin. Decreased gene expressions of interleukin-1α and TNF-α have been observed in HaCaT cells. Moreover, a decreased gene expression of extracellular matrix (ECM)-related protein, including fibronectin (FN1), Col1A1, and Col3A1 caused by UVB was mitigated by SPSR. Furthermore, the clinical trials with 30 volunteers confirmed the significant relief and antiwrinkle effects of the cosmetic formulation containing 0.1% SPSR. These findings implied the promising potential of SPSR as a comprehensive solution for combating the detrimental effects of UVB exposure and maintaining skin health.

We report the occurrence of acquired tumor cell resistance to 5-aminolevulinic acid (ALA)-mediated photodynamic therapy (PDT) in combination with ABCG2 inhibition. ALA-PDT in combination with either an ABCG2 tool inhibitor Ko143 or a repurposed clinically-relevant ABCG2 inhibitor lapatinib was highly effective in eradicating the H4 human glioma cells, resulting in minimal cell survival after treatment. However, after seven rounds of repeated treatments with light dose escalation, the resultant tumor cells became resistant to the combination therapy. The resistant sublines and the parental cell line showed similar ABCG2 activities and protein levels, indicating that it was not ABCG2 that caused the resistance. They also exhibited similar responses to PpIX-PDT and mTOR inhibitor AZD2014, suggesting that alterations in PDT sensitivity and mTOR pathway had little contribution to the development of resistance phenotype. By determining the intracellular and extracellular PpIX levels, the activities and protein levels of heme biosynthesis enzymes, we found that porphobilinogen deaminase (PBGD) activity and protein level were significantly reduced in the resistant sublines, causing resistance to PDT by substantially reducing PpIX biosynthesis. A novel acquired resistance mechanism to ALA-PDT with ABCG2 inhibition has been uncovered.

Gliomas are malignant tumors of the central nervous system, and one severe variant is called gliosarcoma. Photodynamic therapy (PDT) is a technique that stands out in the oncology area for minimizing side effects for the patient, triggering cell death at the site of irradiation, and can be used concomitantly with conventional treatments. This study aimed to evaluate the interaction of chlorine e6 with the cytoskeleton and mitochondria, as well as morphological changes and the death mechanism triggered after PDT. Chlorin e6 was used at concentrations of 200, 12.5, and 6.25 μg/mL, and cytoskeletal changes were analyzed by alpha-tubulin staining and mitochondrial membrane potential (MMP) analysis by JC-1 and Rhodamine 123 in flow cytometry. Surface features were examined using scanning electron microscopy, and the type of cell death mechanism was determined by flow cytometry with annexin and propidium iodide. Changes in the cytoskeleton were observed after PDT. Cytometry showed that cell death occurred predominantly via the apoptosis pathway, followed by the necrosis pathway. Chlorin e6 associated with PDT causes damage to gliosarcoma cells, regardless of concentration, showing cytoskeletal disruption, a decrease in MMP, and the percentage of cell death varies according to the concentration of PS.

Cutaneous overexposure to ultraviolet radiation has a variety of deleterious effects. The extent to which dietary factors are effective at moderating UV damage is a significant issue. Grapes contain phytochemicals that protect against excessive UV damage. Components of grapes, in particular resveratrol, proanthocyanidins, and cyanidin-3-glucoside, are receiving considerable attention for their photoprotective actions because of their lack of toxicity, abundance, and low cost. Resveratrol and proanthocyanidins are potent antioxidants that interfere with signal transduction and immunosuppressive pathways activated by UV radiation, which are responsible for its harmful effects. Studies in humans provide a rationale for their further development as a novel method of photoprotection.

The International Agency for Research on Cancer (IARC) stated that circadian disruption is a potential carcinogen. However, the impact of environmental carcinogens, including sub-erythemal doses of UVB exposure, on circadian rhythms remains unclear. We evaluated the impact of long-term rotating shift, loss of Per1/2 genes, and chronic UVB exposure on the circadian rhythms of SKH-1 mice for up to 7 months. Real-time locomotion and circadian gene expression were measured in these animals. Mice under rotating shift exhibited a longer period of activity of up to 25.20 h, while those under standard light conditions had a clear 24-h rhythm. mPer1/mPer2 mice, conversely, displayed a shortened period of activity of 23.61 h. Interestingly, chronic UVB exposure had no impact on activity rhythms, though it induced skin tumors in all mice. Rotating shift and loss of mPer1/mPer2 led to circadian dysregulation of all core clock genes, with a notable phase difference in Cry1. These findings provide novel insights into environmental and genetic influences on circadian rhythms.

There is a growing need for a skin model that combines the natural physiology of skin while reducing reliance on mice. Natural physiology is achieved by using fresh, intact skin explants sourced from living organisms such as humans or mice. This study focused on the standardization and characterization of an in vitro mouse skin explant model for investigating solar ultraviolet (sUV)-induced skin damage. We developed a protocol to use skin explants derived from the discarded tissue of mice after euthanasia. These explants consist of intact dermal and epidermal layers suspended in cell culture medium and maintained in vitro. To assess the viability of the skin explants, we evaluated tissue morphology (via hematoxylin and eosin [H&E] staining), viability markers, and DNA damage markers. Our ex vivo model preserves the key characteristics and physiological responses of in vivo skin for short incubation periods, while minimizing the use of mice. This model enables the study of DNA damage and repair, and it has broad applications, including studies on skin photoprotection, topical treatments, drug development, and cosmetics.

Spectral Solar Photosynthetically Photon Flux Density (PPFD) (380-780 nm) reaching the surface in different tree shade conditions and heights has been analyzed in order to better understand the different photosynthetic performance of plants depending on their spatial situation, the canopy density and height with respect to the floor. A comparison between the shadow of nine different trees in a sunny day and the case of a cloudy day in an open space has been studied. A poplar, laurel, amber tree, pine, olive tree, fir tree, cypress, elm tree and magnolia tree have been analyzed. The study has been developed in Valencia (Spain) during July and August 2022. Conditions with higher PPFD received are found to be, apart from those of a sunny day, those for cloudy day, and those for the shade of cypress. The case in which less amount of PPFD is received is that under the shade of olive tree. Both with a spectral maximum in the Blue region. It is also remarkable that the PPFD radiation is proportional to the height of measurement at 10 h, but this relationship changes, and at 13 h the relationship between irradiance received and height of measurement is inversely proportional.

Dissolving microneedles (DMNs) is a promising technology for transdermal and intradermal drug delivery. However, effective decontamination protocols are necessary to ensure safety and efficacy in clinical applications. The challenge is to use a technique that preserves mechanical properties, does not introduce chemicals, and can decontaminate DMNs without affecting the drug. With its potent antimicrobial properties and minimal residual effects, ozone presents a novel and safe method for decontaminating DMNs. Specifically, the present study assesses ozone's efficacy in decontaminating DMNs loaded with aminolevulic acid, intended for photodynamic therapy in skin cancer treatment. The results showed that it effectively decontaminates E. coli and S. aureus without compromising the polymer properties or promoting drug degradation. Overall, ozone represents an approach that can be adopted to decontaminate DMNs, offering a safer and effective strategy that enhances their potential to translate to clinical application.

Chlorophyll(Chl)-a derivatives inserting an ethynylene-naphthylene linker between the chlorin π-skeleton and hydroxymethyl group were prepared as models of chlorosomal Chls. Their syntheses were achieved via Sonogashira coupling reaction. Their J-aggregation behaviors were investigated by electronic absorption and circular dichroism spectroscopic measurements. These studies revealed that the 2,6-naphthylene inserted Chl-a derivatives gave the single J-aggregation species in an aqueous Triton X-100 micellar solution with a larger red-shift value (1270 cm^-1) of the Qy band in spite of its longer linker compared with p-phenylene inserted Chl-a derivative (970 cm^-1). These unique optical properties were also discussed based on the computational studies, which indicated the different positional relation of chlorin rings in the assemblies by the linker structure.