Journal of photochemistry and photobiology. B, Biology最新文献

{"title":"Photo-induced nitric oxide modulation in human skin: Impacts of geographic location and seasonality on health and disease","authors":"Paulo E. da Costa ,&nbsp;Maurício S. Baptista","doi":"10.1016/j.jphotobiol.2025.113349","DOIUrl":"10.1016/j.jphotobiol.2025.113349","url":null,"abstract":"<div><div>Depending on geographic location and seasonality, human epidermal tissue is exposed to varying levels of solar radiation. Following light absorption by endogenous photosensitizers, solar photons generate reactive oxidants, inducing oxidative stress that is counteracted by nitric oxide, which inhibits lipid peroxidation and activates antioxidant signaling pathways. Nitric oxide is also quickly transformed in several more stable compounds, which can release nitric oxide at specific conditions, here called nitric oxide reserves. During sun exposure, photolysis of nitric oxide reserves releases bioactive nitric oxide, while inducible nitric oxide synthase is expressed later, synthesizing nitric oxide and replenishing nitric oxide stores. This dynamic process establishes a photoinduced steady state of nitric oxide release and storage. The balance between nitric oxide and reactive oxidants levels is regulated by solar radiation and fluctuates with seasonal and latitudinal variations. Sunlight exposure promotes bioactive nitric oxide production, helping to sustain a healthy nitric oxide/reactive oxidants equilibrium. However, this mechanism is disrupted in chronic inflammatory skin conditions. In this context, elevated expression of inducible nitric oxide synthase is commonly observed in patients with psoriasis, atopic dermatitis and vitiligo. These patients display nitric oxide dysregulation alongside impaired redox regulators, including Nrf2 and NADPH oxidase. Inducible nitric oxide synthase dysregulation, combined with upregulated NADPH oxidase, promotes peroxynitrite formation, further disrupting the nitric oxide-reactive oxidants balance. Pathological inducible nitric oxide synthase activation also leads to nitrite accumulation, impairing redox networks and cellular antioxidant systems. During winter months, reduced solar radiation decreases photolysis-derived nitric oxide and downregulates Nrf2, while inducible nitric oxide synthase and NADPH oxidase remain elevated, exacerbating these conditions. Similar effects occur at high latitudes. Photonic therapies aimed at restoring nitric oxide equilibrium have shown promise in treating such skin disorders.</div></div>","PeriodicalId":16772,"journal":{"name":"Journal of photochemistry and photobiology. B, Biology","volume":"276 ","pages":"Article 113349"},"PeriodicalIF":3.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146049145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modulation of the photodynamic activity of a cinnamoyl-coumarin–RGD peptide conjugate via cucurbit[8]uril supramolecular assembly","authors":"Benjamín Zúñiga ,&nbsp;Paula S. Rivero-Jerez ,&nbsp;Sofia Pérez-Del Pino ,&nbsp;Francisco Bravo-Cabezas ,&nbsp;Francisco Mura ,&nbsp;Pablo Barrias ,&nbsp;Claudio Acuña-Castillo ,&nbsp;Mario A. Faúndez ,&nbsp;Alexis Aspeé ,&nbsp;Daniel Zúñiga-Núñez ,&nbsp;Denis Fuentealba","doi":"10.1016/j.jphotobiol.2026.113376","DOIUrl":"10.1016/j.jphotobiol.2026.113376","url":null,"abstract":"<div><div>Peptide-based photosensitizers (PSs) have emerged as a powerful strategy to overcome the limitations of conventional PSs in photodynamic therapy (PDT), including poor water solubility, low selectivity, and limited phototoxic efficiency. In this study, we synthesized and characterized a novel cinnamoyl–coumarin–RGD peptide conjugate (PS-GG(KG)₃G-RGD), designed to combine tumor-targeting capabilities, improved aqueous solubility, and photodynamic activity modulation by cucurbit[8]uril (CB [8]) complexation. Circular dichroism analysis showed a stable beta-sheet conformation and high-temperature stability for the conjugate. The photophysical behavior of PS-GG(KG)₃G-RGD was evaluated in various solvents, revealing solvent-dependent excited-state dynamics, including the formation of internal charge transfer (ICT) and twisted internal charge transfer (TICT) excited states. Supramolecular complexation with CB[8] resulted in a 1:1 inclusion complex, confirmed by mass spectrometry and Job´s plot; the fluorescence titration showed a high binding constant of (5.0 ± 0.2) × 10⁶ M^-1 and stability under acidic conditions. Notably, PS-GG(KG)₃G-RGD binding to CB[8] modulated fluorescence lifetime without significantly altering singlet oxygen generation. <em>In vitro</em> phototoxicity assays in MCF-7 breast cancer cell line demonstrated that the supramolecular assembly significantly enhanced phototoxicity in tumor cells. These findings support the potential of integrating supramolecular approaches with peptide conjugation to photosensitizers as a promising pathway toward the design of novel phototherapeutic agents.</div></div>","PeriodicalId":16772,"journal":{"name":"Journal of photochemistry and photobiology. B, Biology","volume":"276 ","pages":"Article 113376"},"PeriodicalIF":3.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146125134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Red-emitting carbon dots as highly sensitive fluorescent probes for detecting changes of ClO−in inflammatory systems and cell pyroptosis","authors":"Jing Li ,&nbsp;Xiuying Li ,&nbsp;Liya Wu,&nbsp;Huiying Lv,&nbsp;Te Liu,&nbsp;Hua Yao,&nbsp;Jinlan Jiang","doi":"10.1016/j.jphotobiol.2026.113371","DOIUrl":"10.1016/j.jphotobiol.2026.113371","url":null,"abstract":"<div><div>Inflammatory responses associated with pyroptosis have been shown to promote reactive oxygen species (ROS) production. Among these ROS, hypochlorite (ClO⁻) plays a pivotal role in regulating inflammatory progression. Herein, red-emissive carbon dots (N-CDs) with a maximum emission at 611 nm and a fluorescence quantum yield of 24.1% were developed. The N-CDs exhibit sensitive and selective fluorescence modulation toward ClO⁻, achieving a low detection limit of 0.056 μM. The N-CDs function as versatile fluorescent nanoprobes for monitoring exogenous ClO⁻ dynamics in living cells, evaluating inflammatory status in cellular and zebrafish models, and assessing gouty arthritis in rats. Notably, the N-CDs enable real-time visualization of pyroptosis in living cells through distinct fluorescence signal evolution. Such fluorescence modulation provides a reliable readout for monitoring pyroptosis-associated oxidative stress. This work establishes a sensitive and specific platform for ClO⁻ detection in inflammatory environments and highlights the potential applicability of red-emissive carbon dots for dynamic monitoring of inflammation-related cellular processes.</div></div>","PeriodicalId":16772,"journal":{"name":"Journal of photochemistry and photobiology. B, Biology","volume":"276 ","pages":"Article 113371"},"PeriodicalIF":3.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146157440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Red light–mediated enhancement of the antifungal activity of Physalis angulata against Candida species","authors":"Bianca Borges de Alencar ,&nbsp;Maria Laura Faleiros Ribeiro de Melo ,&nbsp;Wanderson Zuza Cosme ,&nbsp;Matheus Henrique Francisco Dias ,&nbsp;Camila Cristina Baccetti Medeiros ,&nbsp;Rodrigo Sorrechia ,&nbsp;Rosemeire Cristina Linhari Rodrigues Pietro ,&nbsp;Fabiano Guimarães Silva ,&nbsp;Marcio Luís Andrade e Silva ,&nbsp;Wilson Roberto Cunha ,&nbsp;Patrícia Mendonça Pauletti ,&nbsp;Regina Helena Pires ,&nbsp;Ana Helena Januário","doi":"10.1016/j.jphotobiol.2026.113363","DOIUrl":"10.1016/j.jphotobiol.2026.113363","url":null,"abstract":"<div><div><em>Physalis angulata</em> L. (Solanaceae) is widely recognized for its therapeutic applications in traditional medicine. This study evaluated the antifungal activity of <em>P. angulata</em> (PA) and the influence of red LED–mediated photodynamic therapy (PDT) on planktonic cells and biofilms of <em>Candida albicans</em>, <em>Nakaseomyces glabratus</em>, and <em>Candida parapsilosis</em>. The withanolide 4β-hydroxywithanolide E was isolated from PA, and UPLC–MS analysis of the active fraction (PA-F) in negative ion mode revealed the predominance of eleven withanolides, including aglycone and glycosylated forms belonging to the 5β,6β-epoxide and 5-ene classes. The crude PA extract showed no antifungal activity (MIC &gt;2000 μg/mL) against the tested strains, whereas PA-F exhibited a MIC of 250 μg/mL against <em>C. albicans</em> and 2000 μg/mL against <em>N. glabratus</em> and <em>C. parapsilosis</em>. Notably, exposure of yeast biofilms to PA-F (250 μg/mL) followed by red LED irradiation resulted in a pronounced reduction in viable cells, reaching 4.88 ± 0.12, 4.29 ± 0.15, and 4.16 ± 0.06 log₁₀ CFU/mL for <em>C. albicans, N. glabratus</em>, and <em>C. parapsilosis</em>, respectively, indicating fungicidal activity. These findings demonstrate a light-dependent enhancement of antifungal efficacy, supporting the potential of <em>P. angulata</em>–derived withanolide fractions as photo-responsive agents in antifungal photodynamic strategies.</div></div>","PeriodicalId":16772,"journal":{"name":"Journal of photochemistry and photobiology. B, Biology","volume":"275 ","pages":"Article 113363"},"PeriodicalIF":3.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145928577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lipid assemblies mediating the fusion of photosystem-II enriched membranes characterized by DPH (1,6-diphenyl-1,3,5-hexatriene) fluorescence and fluorescence anisotropy lifetimes","authors":"Kinga Böde ,&nbsp;Krisztina Sebők-Nagy ,&nbsp;Ondřej Dlouhý ,&nbsp;Gábor Steinbach ,&nbsp;Aleš Benda ,&nbsp;Győző Garab ,&nbsp;Tibor Páli","doi":"10.1016/j.jphotobiol.2026.113361","DOIUrl":"10.1016/j.jphotobiol.2026.113361","url":null,"abstract":"<div><div>The lipid composition of thylakoid membranes (TMs), the site of light reactions in oxygenic photosynthetic organisms, is dominated by the non-bilayer lipid species monogalactosyldiacylglycerol. It has been documented that plant TMs display strong lipid polymorphisms (Garab et al. 2022 Prog Lipid Res 86:101163). Recently, we have also shown that BBY membrane sheets, large, laterally fused photosystem-II (PSII) enriched membrane pairs, beside the lamellar phase, contain an intense isotropic phase, the lipid molecules of which mediate the fusion of membranes (Böde et al. 2024 Photosynth Res 161:127–140). To demonstrate the composite nature of BBY, we employed confocal laser scanning microscopy, using the lipid-label BODIPY-phosphatydilcholine and chlorophyll-a fluorescence emissions. To characterize the physico-chemical microenvironments of lipid molecules, we stained BBY membranes with the hydrophobic fluorescent dye DPH (1,6-diphenyl-1,3,5-hexatriene). DPH emission spectra from face- and edge-aligned BBY membranes indicated the existence of at least two distinct microenvironments. Fluorescence lifetime analyses revealed three components; the fastest one was sensitive to the enzymatic treatment with wheat germ lipase (WGL), which had earlier been shown to selectively eliminate the isotropic lipid phase of BBY and to disassemble the large sheets into its constituent membrane pairs of grana. Although the anisotropic fluorescence decay kinetics discerned no lifetime heterogeneity of the untreated DPH-stained BBY, WGL treatment led to the appearance of a second lifetime component. These data provide independent experimental evidence on the lipid polymorphism of BBY membranes and reveal that the bilayer lipids and the non-bilayer lipid arrays mediating the fusion of TMs possess distinct physico-chemical environments.</div></div>","PeriodicalId":16772,"journal":{"name":"Journal of photochemistry and photobiology. B, Biology","volume":"275 ","pages":"Article 113361"},"PeriodicalIF":3.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Membrane-targeted photodynamic mechanisms of methylene violet 3RAX in melanoma models","authors":"Thais Soares de Oliveira ,&nbsp;Mirella Boaro Kobal ,&nbsp;André Satoshi Ferreira ,&nbsp;Alexandre Mendes de Almeida Junior ,&nbsp;Karina Alves Toledo ,&nbsp;Sabrina Aléssio Camacho ,&nbsp;Pedro Henrique Benites Aoki","doi":"10.1016/j.jphotobiol.2025.113353","DOIUrl":"10.1016/j.jphotobiol.2025.113353","url":null,"abstract":"<div><div>Melanoma, while less prevalent than other skin cancers, remains the most lethal and aggressive type, posing significant treatment challenges. Photodynamic therapy (PDT) offers a promising, less invasive alternative to conventional therapies. In this study, we explored the potential of methylene violet 3RAX (MV), a phenazine-family photosensitizer, for PDT applications through <em>in vitro</em> assays and Langmuir monolayer studies, focusing on its interactions with cell lipid extract membranes derived from two melanoma lineages, A375 and SH-4. Our results demonstrate that MV is non-cytotoxic in the absence of light irradiation but exhibits concentration-dependent cytotoxicity upon photoactivation. Flow cytometry confirmed late apoptosis as the dominant cell death pathway under irradiation. Langmuir isotherms revealed that MV adsorbs onto anionic head groups of the lipid monolayers, particularly interacting with phosphate groups, promoting molecular organization. Upon irradiation, significant material loss to the subphase was observed, suggesting photooxidative interactions with lipid tail unsaturations, leading to hydroperoxidation, chain cleavage, and membrane destabilization. These findings highlight MV dual role as an effective photosensitizer and a molecular probe for membrane interactions, providing new insights into its mechanisms of action in PDT.</div></div>","PeriodicalId":16772,"journal":{"name":"Journal of photochemistry and photobiology. B, Biology","volume":"275 ","pages":"Article 113353"},"PeriodicalIF":3.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145928646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transcriptomic and functional profiling reveal autophagy inhibition and persistent bioenergetic collapse following parallel photodamage to lysosomes and mitochondria","authors":"Márcia Silvana Freire Franco ,&nbsp;Felipe Gustavo Ravagnani ,&nbsp;Suely Kazue Nagahashi Marie ,&nbsp;Sueli Mieko Oba-Shinjo ,&nbsp;Leonardo Vinicius Monteiro de Assis ,&nbsp;Maurício S. Baptista","doi":"10.1016/j.jphotobiol.2026.113364","DOIUrl":"10.1016/j.jphotobiol.2026.113364","url":null,"abstract":"<div><div>Photodynamic therapy (PDT) using 1,9-dimethyl methylene blue (DMMB) induces coordinated mitochondrial and lysosomal damage and results in strong cellular death induction. However, the underlying transcriptional regulation in response to DMMB remains elusive. We compared the transcriptome response of photoactivated DMMB (paDMMB) to the gene signature triggered by autophagy-modulating agents: rapamycin (an autophagy activator) and bafilomycin A1 (an autophagy inhibitor).</div><div>Transcriptome analysis revealed a pronounced transcriptomic response to paDMMB, with 884 differentially expressed genes (DEGs), compared to 291 for bafilomycin and 154 for rapamycin. paDMMB treatment upregulated genes associated with autophagy, mitochondrial stress responses, and proteostasis, while downregulating genes involved in miRNA processing and lipid catabolism. Rapamycin treatment downregulated amino acid biosynthesis pathways, while upregulating processes associated with nutrient starvation. Conversely, bafilomycin treatment upregulated genes related to lipid metabolism, while suppressing cytoskeletal programs. We observed that approximately 80% of bafilomycin DEGs also changed in paDMMB-treated cells, and about 96% of these shared genes showed concordant regulation. This suggests that the paDMMB molecular signature is consistent with the inhibition of autophagic flux.</div><div>Among the several biological processes affected by paDMMB, mitochondrial-related processes were enriched. To determine whether the acute transcriptome changes caused by paDMMB led to persistent functional effects, we stimulated cells with DMMB and assessed mitochondrial respiration after a recovery period. paDMMB reduced basal respiration, ATP production, proton leak, and maximal respiration. These effects were not further altered by bafilomycin co-treatment but were markedly exacerbated by rapamycin.</div><div>Collectively, we show that paDMMB leads to a transcriptome rewiring, closely resembling autophagy inhibition with a sustained mitochondrial dysfunction. These findings provide a valuable resource to understand the interplay between DMMB-induced lysosomal stress, transcriptional regulation, and PDT.</div></div>","PeriodicalId":16772,"journal":{"name":"Journal of photochemistry and photobiology. B, Biology","volume":"275 ","pages":"Article 113364"},"PeriodicalIF":3.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146003622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PEGylated isothiocyanate-functionalized zinc(II) phthalocyanine exhibits cell-type dependent photodynamic activity in 2D and 3D tumor models","authors":"Mukaddes Özçeşmeci ,&nbsp;Seyma Isik ,&nbsp;Taylan Samsunlu ,&nbsp;Ekrem Kaplan ,&nbsp;Göknur Yaşa Atmaca ,&nbsp;Ayfer Kalkan Burat ,&nbsp;Ali Erdoğmuş ,&nbsp;Muge Serhatli ,&nbsp;Esin Hamuryudan","doi":"10.1016/j.jphotobiol.2026.113354","DOIUrl":"10.1016/j.jphotobiol.2026.113354","url":null,"abstract":"<div><div>This study reports the synthesis and characterization of an asymmetric zinc(II) phthalocyanine (<strong>5</strong>) containing three tetraethyleneglycol monomethyl ether groups and one isothiocyanatophenoxy group at its periphery. The isothiocyanate unit was selected to ensure selective bioconjugation under mild reaction conditions and to reduce side product formation, while tetraethyleneglycol monomethyl ether groups were incorporated to increase solubility and tailor photophysical and photochemical properties relevant to photodynamic therapy applications. The compound showed a singlet oxygen quantum yield (Φ_Δ) of 0.38, confirming efficient photosensitizer performance. Photodynamic activity was evaluated across multiple cancer cell lines in both 2D monolayer and 3D spheroid cultures. In 2D models, compound 5 produced pronounced light-dependent cytotoxicity accompanied by increased intracellular ROS. Cell-death profiles varied among cancer types, with FaDu cells showing the highest sensitivity under the tested conditions, consistent with differences in cellular susceptibility to compound 5–mediated PDT. In 3D spheroids, efficacy was reduced, in line with known limitations of PDT in compact tumor-like structures, including restricted light propagation, oxygen gradients, and limited compound penetration. Minimal phototoxicity in non-malignant fibroblasts under the same conditions suggests preferential photodynamic activity in the tested cancer models. Overall, these results support the PDT potential of compound 5 and highlight the influence of cellular context and 3D architecture on treatment responses.</div></div>","PeriodicalId":16772,"journal":{"name":"Journal of photochemistry and photobiology. B, Biology","volume":"275 ","pages":"Article 113354"},"PeriodicalIF":3.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145928576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acute UV response of early erythema and late edema in SKH1 mice","authors":"Szabolcs Bozsányi ,&nbsp;Rhea Carmel Glen Rodrigues ,&nbsp;Ruby Acquah ,&nbsp;Erin C. Tracy ,&nbsp;Sean P. Murphy ,&nbsp;Jocelyn Tracy ,&nbsp;Li Yan ,&nbsp;Mehdi Boostani ,&nbsp;Hamid-Reza Rezvani ,&nbsp;Wendy J. Huss ,&nbsp;Gyorgy Paragh","doi":"10.1016/j.jphotobiol.2026.113369","DOIUrl":"10.1016/j.jphotobiol.2026.113369","url":null,"abstract":"<div><div>In human skin, erythema assessed 24 h after ultraviolet (UV) exposure is a non-invasive method for determining the acute UV response. Although erythema is often reported in murine models as a measure of acute UV response, the most informative timepoint after UV exposure is unclear because of variability in mouse strain, sex, and light source. Our current work addresses this critical gap by elucidating the development of erythema and edema over time after acute UV irradiation with solar-simulator UV (SSUV) or UVB light in female or male SKH1 mice. Cutaneous erythema was assessed with ImageJ on digital photographs, and edema was assessed using optically guided high-frequency ultrasound (OG-HFUS) to measure skin thickness and a visual edema scale up to 72 h after UV exposure. Erythema was observed between 4 and 10 h in both female and male mice at most doses of SSUV or UVB irradiation. Erythema induced by irradiation doses of 200, 300, 400 mJ/cm² peaked earlier at the 4–6 h timepoint with SSUV irradiation compared to the same doses of UVB that peaked at the 6–8 h timepoint. At 24 h, edema-induced blanching of the skin masked the erythema, resulting in the highest-dose area having a lower erythema index than non-irradiated areas. Edema was dose-dependent (with SSUV exposure) and peaked between 24 and 48 h using both the OG-HFUS and visual edema scale. Erythema measurement at 4–8 h after UV is optimal for assessing the acute UV response in the SKH1 mouse model at lower irradiation doses. Whereas edema measured at 24–48 h after UV exposure is a sex-neutral and reliable universal measure of acute UV response in SKH1 mouse skin at high UV irradiation doses.</div></div>","PeriodicalId":16772,"journal":{"name":"Journal of photochemistry and photobiology. B, Biology","volume":"275 ","pages":"Article 113369"},"PeriodicalIF":3.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146010861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Photoperiod alters the diurnal rhythm pattern of testicular transcription and metabolism in Brandt's voles","authors":"Hong Sun ,&nbsp;Wenbo Xu ,&nbsp;Maolin Huang ,&nbsp;Jieyu Huang ,&nbsp;Wenju Yang ,&nbsp;Qianqian Zhang ,&nbsp;Lijuan Zhao ,&nbsp;Dawei Wang ,&nbsp;Zhenlong Wang","doi":"10.1016/j.jphotobiol.2026.113367","DOIUrl":"10.1016/j.jphotobiol.2026.113367","url":null,"abstract":"<div><div>Photoperiod changes serve as critical environmental signals for seasonally reproducing animals, with their decoding dependent on the precise functioning of endogenous circadian clocks. Here we conducted a comprehensive analysis of diurnal transcripts and metabolites profiles in the testes of Brandt's voles (<em>Lasiopodomys brandtii</em>) under long photoperiod (LP) and short photoperiod (SP), to elucidate the role of circadian rhythms within peripheral testicular tissue in regulating reproduction. Phenotypic results demonstrated that LP promoted testicular development, whereas SP suppressed it. Then we observed relatively weaker transcriptional and metabolic rhythmicity in the testes under both photoperiods. The function of diurnal rhythmic genes was mainly related to homeostasis, developmental, reproductive behavior, motility and sperm flagellum assembly pathways, suggesting that diurnal clocks act as photoperiodic timekeeper for reproductive timing. In contrast, testosterone biosynthesis and key energy metabolism pathways essential for spermatogenesis were largely governed by non-rhythmic genes expression patterns. Together, these findings underscore the non-uniform pervasiveness of diurnal rhythmicity in testis, where reproductive initiation driven by the diurnal clock, while subsequent spermatogenic processes progressively deviate from 24 h rhythmicity.</div></div>","PeriodicalId":16772,"journal":{"name":"Journal of photochemistry and photobiology. B, Biology","volume":"275 ","pages":"Article 113367"},"PeriodicalIF":3.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}