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Главная страница Новости науки Journal of Photochemistry and Photobiology B: Biology
Новости науки
ScienceDirect Publication: Journal of Photochemistry and Photobiology B: Biology
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  • Photobiomodulation improved stereological parameters and sperm analysis factors in streptozotocin-induced type 1 diabetes mellitus

    Publication date: September 2018

    Source: Journal of Photochemistry and Photobiology B: Biology, Volume 186

    Author(s): Sara Dadras, Mohammad-Amin Abdollahifar, Hamid Nazarian, Seyed Kamran Ghoreishi, Somaye Fallahnezhad, Parvaneh Naserzadeh, Vahid Jajarmi, Sufan Chien, Mohammad Bayat

    Abstract

    The aim of this study was to evaluate the effect of photobiomodulation (PBM) on testicular tissues and fresh sperm analysis factors in streptozotocin (STZ)-induced type one diabetes mellitus (T1DM) mice.

    T1DM was induced in 15 male Syrian mice by injection of 200 mg/kg STZ. After one month, mice were divided randomly into three groups, harboring 5 mice each: 1, control group; 2, first laser group (890 nm, 80 Hz, 0.03 J/cm2) and 3, second laser group (0.2 J/cm2). Then the mice were euthanized and testicles were dissected for stereological studies, and both epididymis and vas deferens were removed for fresh sperm analysis. Data were analyzed by statistical methods.

    A significant increase was observed in the Sertoli cell count in both PBM groups, compared to the control group. In addition, the second PBM group shows a significant increase in the Sertoli cell count, compared to the first PBM group. Both PBM groups show significant increase in the Leydig cell count, compared to the control group. There were significant increases of the length in the seminiferous tubules in both PBM groups, compared to the control group. In addition, the second PBM group showed a significant increase of the length in the seminiferous tubules, compared to the first PBM group. The second PBM group showed a significant increase in the sperm count, compared to the control, and first PBM groups. The first PBM group showed a significant increase in sperm count, compared to the control group. The sperm motility and count were significantly increased in the second PBM group, compared to the control and first PBM groups. The sperm motility was significantly increased in the first PBM group, compared to the control group.

    PBM with 0.2 J/cm2 and 0.03 J/cm2 energy densities significantly improved the stereological parameters and fresh sperm analysis factors, compared to the control group in STZ-induced T1DM in mice. Moreover, the PBM with 0.2 J/cm2 energy density was statistically more effective, compared to the 0.03 J/cm2.



  • Solar energy at birth and human lifespan

    Publication date: September 2018

    Source: Journal of Photochemistry and Photobiology B: Biology, Volume 186

    Author(s): George E. Davis, Walter E. Lowell

    Abstract
    Purpose

    The purpose of this paper is to examine the role of UVR at birth and its relationship to lifespan and determine whether there are significant differential effects on sex and race. We test if variation in UVR, as determined by solar cycles (long-term variation), is related to survival as measured by age at death.

    Methods

    The data used 78 million death records from the National Center for Health Statistics (NCHS) from 1979 to 2013 with accidents, suicides, and war casualties deleted resulted in ~63 million records. Records of persons ≤ 47 years old were also scrubbed because we could not show an effect on lifespan based upon the intensity of solar energy as reflected by sunspot number (SSN). This we hypothesize is due to the protective effect of the hormones associated with growth and reproduction. Also selected were persons afflicted with multiple sclerosis (MS).

    Results

    Males of all races born with a UVR intensity as estimated by sunspot number (SSN) ≤ 90 had an average lifespan of 74.4 years, for females of all races, 78.1 years; males born with >90 had an average lifespan of 66.3 years, for females of all races, 70.2 years, resulting in a lifespan decrease of 8.1 years for males and 8.5 years for females. For African-American males born ≤ 90 SSN, 70.8 years and for >90 SSN, 62.5 years, an 8.3-year decrease; similarly, for African-American females ≤ 90 SSN, 75.0, for >90 SSN, 65.4 years, a 9.6-year decrease. Higher solar energy at birth had an adverse effect on human lifespan. We also found that there were twice as many persons with MS born in >80–90 SSN as in the general population.

    Conclusions

    There is a statistically significant inverse relationship between exposure to solar energy at birth and average human lifespan. Solar energy by some mechanism alters the epigenome at birth, but the effect of higher solar energy becomes apparent after the age of natural selection.



  • Biogenic synthesis of gold nanoparticles and their application in photocatalytic degradation of toxic dyes

    Publication date: September 2018

    Source: Journal of Photochemistry and Photobiology B: Biology, Volume 186

    Author(s): Debjani Baruah, Monmi Goswami, Raj Narayan Singh Yadav, Archana Yadav, Archana Moni Das

    Abstract

    Plants and their extracts play an important role in the green synthesis of nanoparticles mainly because of their environmental benignity. Based on plant extracts number of metal nanoparticles have been synthesized. In our study, we report a green technique for the synthesis of gold nanoparticles using the aqueous extracts of Alpinia nigra leaves and their photocatalytic activities. The antioxidant, antibacterial and antifungal potential of the synthesized nanoparticles were also evaluated. The aqueous extract of the plant is rich in flavonoids with Total Flavonoid Content of 491mgRE/g extract. The presence of flavonoids was further confirmed through analytical High Performance Liquid Chromatography (HPLC) analysis. The A. nigra mediated syntheses of gold nanoparticles (ANL-AuNPs) were characterized by UV–Vis spectrophotometer, Fourier Transform Infrared (FTIR) Spectroscopy, X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM). The crystalline nature of the ANL-AuNPs was confirmed by the powder XRD analysis. The TEM micrographs showed that the ANL-AuNPs was predominantly spherical in shape and the average particle size was 21.52 nm. The polyphenolics and other functional groups present in the aqueous extract that acted as reducing and capping agent in the synthesis of the Au-NPs were identified via FTIR spectral analysis. These green synthesized nanoparticles exhibited antioxidant activity with IC50 value of 52.16 μg/ml and showed inhibition in the growth of both gram-positive and gram-negative bacteria. The pathogenic fungus, Candida albicans was also susceptible to these nanoparticles. The ANL-AuNPs in the presence of sunlight catalyzed the degradation of the anthropogenic pollutant dyes, Methyl Orange and Rhodamine B with percent degradation of 83.25% and 87.64% respectively. The photodegradation process followed pseudo first order kinetic model. These results confirm that Alpinia nigra is a potential bioresource for the synthesis of Au-NPs with versatile applications.

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  • 970 nm low-level laser affects bone metabolism in orthodontic tooth movement

    Publication date: September 2018

    Source: Journal of Photochemistry and Photobiology B: Biology, Volume 186

    Author(s): Li-Fang Hsu, Meng-Huan Tsai, Bei-En Chang, Yi-Jane Chen, Chung-Chen Jane Yao

    Abstract
    Objective

    During orthodontic tooth movement (OTM), the speed of movement depends on the rate of bone turnover. In this study, we used a rat model to investigate the effect of 970 nm low-level laser therapy (LLLT) on OTM under different dose and frequency protocols.

    Methods

    We first compared the OTM rates between the OTM only control and the OTM + LLLT group (1250 J/cm2) in Experiment 1 and showed that LLLT significantly increased OTM. In Experiment 2, we employed 3 different LLLT protocols: the low-dose group and the high-dose group receiving 5 doses of 750 J/cm2 and 15,000 J/cm2 of LLLT every 3 days, respectively, and the early high-dose group which received 5 daily doses at 15,000 J/cm2 at the beginning of the experiments. The OTM-only control group received no LLLT. Tooth movement rate was measured through sequential silicone impressions. MicroCT was also performed to evaluate bone de-mineralization rate. Bone histmorphometry was used to compare the bone turnover rate between LLLT group and control group. Finally, TRAP, Osteocalcin, and VEGF expression is evaluated by immunohistochemistry (IHC) in tissue sections.

    Results

    When LLLT treatment was given every three days, both the 1250 J/cm2 and 15,000 J/cm2 groups showed significantly increased OTM compared to the control group. No significant difference was observed in the 750 J/cm2 group, or in the early irradiation group, when compared with controls, although 750 J/cm2 showed the same trend of accelerating OTM. The MicroCT result of rat maxilla demonstrated that LLLT increased bone remodeling and showed decreased bone mineral density and bone volume/total volume in the furcation areas of the maxillary first molars at the end of experiment. LLLT without OTM increased bone turnover as evidenced by fluorochrome incorporation. Immunohistochemistry analyses revealed high osteocalcin expression at later stages of OTM in the LLLT group, while VEGF expression was highly induced in the LLLT + OTM group at an early stage.

    Conclusion

    Our results suggest that the 970 nm LLLT increases the rate of OTM in a dose-sensitive and frequency-dependent manner. Further animal and human studies are needed to determine the optimal timing and dosage of LLLT for OTM acceleration.



  • Red light-emitting diode irradiation regulates oxidative stress and inflammation through SPHK1/NF-κB activation in human keratinocytes

    Publication date: September 2018

    Source: Journal of Photochemistry and Photobiology B: Biology, Volume 186

    Author(s): Qiaochu Sun, Hye-Eun Kim, Hyejoung Cho, Shuhan Shi, Byungkuk Kim, Okjoon Kim

    Abstract

    Oxidative stress, in which the amount of oxidants exceeds the capacity of antioxidant defense system, is a well-accepted pathogenesis of several human diseases. Light-emitting diode irradiation (LEDI) is an efficient strategy to counteract this condition. The biological effect of phototherapy, using visible light, has attracted recent attention especially in dermatological practice. However, little is known about the molecular mechanism of the anti-oxidant and anti-inflammatory effects of red light irradiation. We evaluated these effects of LEDI in HaCaT human keratinocyte cells under phorbol-12-myristate-13-acetate (PMA) induced reactive oxygen species (ROS). Microarray analysis revealed changes in 309 genes after LEDI. LEDI at 625 nm produced ROS scavenging and anti-inflammatory effects. One of the most important genes identified by microarray analysis was sphingosine kinase-1 (SPHK1), which is a key molecule in sphingolipid metabolism. SPHK1 knock-down drastically reduced ROS scavenging efficiency as well as expression levels of inflammation-related proteins in PMA-treated HaCaT cells. These results not only indicate the potential for the clinical application of 625-nm LEDI in treating skin disorders via ROS and/or inflammation, but also suggest SPHK1 as a potential therapeutic target in phototherapy.

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  • Tuning the chain length of new pyrene derivatives for site-selective photocleavage of avidin

    Publication date: September 2018

    Source: Journal of Photochemistry and Photobiology B: Biology, Volume 186

    Author(s): Sudarat Yenjai, Challa V. Kumar, Mayuso Kuno, Teerayuth Liwporncharoenvong, Siritron Samosorn, Apinya Buranaprapuk

    Abstract

    Rational design of photoreagents with systematic modifications of their structures can provide valuable information for a better understanding of the protein photocleavage mechanism by these reagents. Variation of the length of the linker connecting the photoactive moiety with the protein anchoring-group allowed us to investigate the control of the protein photocleavage site. A series of new photochemical reagents (PMA-1A, PMA-2A and PMA-3A) with increasing chain lengths is examined in the current study. Using avidin as a model system, we examined the interaction of these probes by UV–Vis, fluorescence spectroscopic methods, photocleavage and computational docking studies. Hypochromism of the absorption spectrum was observed for the binding of these new photochemical reagents with estimated binding constants (Kb) of 6.2 × 105, 6.7 × 105 and 4.6 × 105 M−1, respectively. No significant changes of Stern-Volmer quenching constant (Ksv) with Co(NH3)6Cl3 has been noted and the data indicated that the probes bind near the surface of the protein with sufficient exposure to the solvent. Photoexcitation of the probe-avidin complex, in the presence of Co(NH3)6Cl3, resulted in protein fragmentation, and the cleavage yield decreased with the increase in the linker length, and paralleled with the observed Ksv values. Amino acid sequencing of the photofragments indicated that avidin is cleaved between Thr77 and Val78, as a major cleavage site for all the three photoreagents. This site is proximate to the biotin binding site on avidin, and molecular docking studies indicated that the H-bonding interactions between the polar end-group of the photoreagents and hydrophilic amino acids of avidin were important in positioning the reagent on the protein. The major cleavage site, at residues 77–78, was within 5 Å of the pyrenyl moiety of the probe, and hence, molecular tuning of the linker provided a simple approach to position the photoreagent along the potential photocleavage site.

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  • Influence of darkness on pigments of Tetraselmis indica (Chlorodendrophyceae, Chlorophyta)

    Publication date: September 2018

    Source: Journal of Photochemistry and Photobiology B: Biology, Volume 186

    Author(s): Sangeeta Mahableshwar Naik, Arga Chandrashekar Anil

    Abstract

    In the photic zone, phytoplankton experience diurnal variation in light intensity. However, prolonged exposure to aphotic condition influences their physiological state. Pigment composition is a useful biomarker to decipher cells physiological state and adaptive response to changing environmental conditions. Chlorophyll, a natural pigment, is biosynthesised even in darkness and studies have shown this ability is determined by genetic characteristics of an organism. The purpose of this study was to examine the influence of darkness on pigments and chlorophyll autofluorescence of Tetraselmis indica. Dark exposure (up to 6 months) had no significant impact on chlorophyll a and b concentration, whereas carotenoids were enhanced. Upon re-illumination pigments gradually recovered to pre-dark phase condition. These adaptive survival strategies of T. indica by altering pigment concentration in response to prolonged darkness are interesting. The absence of loroxanthin and loroxanthin esters in T. indica is reported in a first Tetraselmis species so far. In addition, the evaluation of autofluorescence and cellular chlorophyll concentration pointed out that they are not interdependent in this species. Hence, careful consideration of these two factors is needed when either of them is used as a proxy for other. The results obtained encourage a thorough study of pigment analysis, especially when subjected to darkness, to elucidate potential role in the evolution, chemotaxonomy, and survivability of species.



  • MiR-340/iASPP axis affects UVB-mediated retinal pigment epithelium (RPE) cell damage

    Publication date: September 2018

    Source: Journal of Photochemistry and Photobiology B: Biology, Volume 186

    Author(s): Jiazhao Yan, Yuhui Qin, Jingsheng Yu, Qinghua Peng, Xiangdong Chen

    Abstract

    Long-term exposure to ultraviolet B (UVB) light increases the risk of UVB damage due to increased UVB absorption by the retina and may further lead to age-related eye diseases. The retinal pigment epithelium (RPE) cell is a main target of UVB reaching the retina; its degeneration is an essential event in UVB-mediated age-related macular degeneration (AMD). Herein, we first evaluated the expression and effect of iASPP, an inhibitory regulator of apoptosis, in UVB-induced RPE cell damage. Through the mechanism of RNA interference at the post-transcriptional level, miRNA affects a variety of cellular processes, including UVB-mediated cell damage. We next screened for upstream candidate miRNAs that may regulate iASPP expression. Among 8 candidate miRNAs, UVB significantly increased miR-340 levels. We also confirmed the direct binding of miR-340 to the 3′UTR of iASPP, and assessed the combined effect of miR-340 and iASPP on UVB-induced RPE cell damage. Taken together, we demonstrated the possible mechanisms involved in UVB-induced retinal damage. In RPE cells, UVB irradiation inhibits iASPP expression through inducing miR-340 expression, thereby promoting RPE cell apoptosis and suppressing cell viability via affecting p53, p21 and caspase-3 protein expression. Targeting miR-340 to rescue iASPP expression in RPE cells may help treat UVB-mediated retinal damage.



  • The carotenoid Bixin found to exhibit the highest measured carotenoid oxidation potential to date consistent with its practical protective use in cosmetics, drugs and food

    Publication date: September 2018

    Source: Journal of Photochemistry and Photobiology B: Biology, Volume 186

    Author(s): Sefadzi Tay-Agbozo, Shane Street, Lowell Kispert

    Abstract

    The electrochemical oxidation potentials of cis bixin correspond to the production of the carotenoid radical cation, Car+ and dication Car++. The oxidation is a two-electron process with oxidation potentials at ~0.94 and ~1.14 V vs SCE (reference to ferrocene at 0.528 V) in THF. These potentials are higher than that of symmetrical canthaxanthin at 0.775 V and 0.972 V and for β-carotene at 0.634 V and 0.605 V respectively. The second oxidation potential for canthaxanthin is higher by 0.20 V than the first. Similar difference is observed for bixin. In contrast, the second oxidation potential for β-carotene is lower by 30 mV than that of the first. Reduction potentials were found to occur at ~−0.69 and ~−1.22 V vs SCE. The lifetime of the radical cation of cis bixin, Car+, is short and decays rapidly at ambient temperature. The suggested scavenging ability of cis bixin towards reactive oxidative oxygen species is estimated to be 44. On the other hand, that of β-carotene, symmetrical canthaxanthin and the dicyano substituted carotenoid which exhibit oxidation potentials of 0.634 V, 0.775 V and 0.833 V vs SCE were measured to be 0.64, 1.96 and 23.60 respectively. The non-reversible electrochemical measurements suggest the tendency for bixin to react with trace amounts of reactive oxygen species (OH, O2, OOH).

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  • Immunosenescence-like state is accelerated by constant light exposure and counteracted by melatonin or turmeric administration through DJ-1/Nrf2 and P53/Bax pathways

    Publication date: September 2018

    Source: Journal of Photochemistry and Photobiology B: Biology, Volume 186

    Author(s): Hanan A. El-Bakry, Ismail Ahmed Ismail, Safaa S. Soliman

    Abstract

    The awareness of the interrelationship between immunosenescence and constant light exposure can provide new insights into the consequences of excessive exposure to light at night due to light pollution or shift work. Here, we investigated whether constant light exposure (LL) acts as an inducer of immunosenescence. We also determined the role of melatonin or turmeric in reversing the putative effects of constant light and explored for the first time the underlying molecular mechanisms. Young (3–4-month-old) rats were exposed daily to LL alone or in combination with each of melatonin and turmeric for 12 weeks. A group of aged rats (18-months old; n = 6) was used as a reference for natural immunosenescence. Constant light exposure resulted in remarkable pathophysiological alterations resembling those noticed in normal aged rats, manifested as apparent decreases in antioxidant activities as well as Nrf2 and DJ-1 expressions, striking augmentation in oxidative stress, proinflammatory cytokines and expression of TNFα, Bax, and p53 genes, and deleterious changes of lymphoid organs, Co-administration of melatonin or turmeric was able to reverse all alterations induced by LL through upregulation of Nrf2/DJ-1 and downregulation of p53/Bax pathways. These data suggest that LL accelerates immunosenescence via oxidative stress and apoptotic pathways. They also demonstrate for the first time that turmeric is comparable to melatonin in boosting the immune function and counteracting the LL-associated immunosenescence. These effects suggest that turmeric supplementation can be used as an inexpensive intervention to prevent circadian disruption-related immunosenescence. However, to validate the effects of turmeric on humans further studies are warranted.



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