Clinical efficacy of intradermal type Ⅰ collagen injections in treating skin photoaging in patients from high-altitude areas

BACKGROUND Photoaging,a result of chronic sun exposure,leads to skin damage and pigmentation changes.Traditional treatments may have limitations in high-altitude areas like Yunnan Province.Intradermal Col Ⅰ injections stimulate collagen production,potentially improving skin quality.This study aims to assess the efficacy and safety of this treatment for photoaging.AIM To evaluate the efficacy and safety of intradermal typeΙcollagen(ColΙ)injection for treating photoaging.METHODS This prospective,self-controlled study investigated the impact of intradermal injections of ColΙon skin photodamage in 20 patients from the Yunnan Province.Total six treatment sessions were conducted every 4 wk±3 d.Before and after each treatment,facial skin characteristics were quantified using a VISIA skin detector.Skin thickness data were assessed using the ultrasound probes of the Dermalab skin detector.The Face-Q scale was used for subjective evaluation of the treatment effect by the patients.RESULTS The skin thickness of the right cheek consistently increased after each treatment session compared with baseline.The skin thickness of the left cheek significantly increased after the third through sixth treatment sessions compared with baseline.The skin thickness of the right zygomatic region increased after the second to sixth treatment sessions,whereas that of the left zygomatic region showed a significant increase after the fourth through sixth treatment sessions.The skin thickness of both temporal regions significantly increased after the fifth and sixth treatment sessions compared with baseline(P<0.05).These findings were also supported by skin ultrasound images.The feature count for the red areas and wrinkle feature count decreased following the treatment(P<0.05).VISIA assessments also revealed a decrease in the red areas after treatment.The Face-QSatisfaction with Facial Appearance Overall and Face-Q-Satisfaction with Skin scores significantly increased after each treatment session.The overall appearance of the patients improved after treatment.CONCLUSION Intradermal ColΙinjection improves photoaging,with higher patient satisfaction and fewer adverse reactions,and could be an effective treatment method for populations residing in high-altitude areas.

Elucidating the Molecular Mechanism of Dynamic Photodamage of Photosystem II Membrane Protein Complex by Integrated Proteomics Strategy

Photosystem II(PSII),as a multiple-subunit chloroplast membrane-associated pigment-protein complex on the thylakoid membrane,is a primary target of light-induced photodamage.However,the overall molecular details of the conformation and composition dynamics of PSII photodamage are still controversial.In this study,we investigated systematically the dynamic conformation,degradation,and oxidation processes of PSII photodamage by integrating chemical cross-linking and top-down proteomics strategies.

The photodamage process of pigments and proteins of PSI complexes from Spinacia Oleracea L.

Purified PSI complexes from Spinacia Oleracea L. were exposed to the strong light (PFD=2300μmol m-2s-1) for various period. Along with the illumination the photo-damage process of pigments and proteins of PSI complexes was investigated using absorption, fluorescence, circular dichroism (CD) spectroscopy and SDS-PAGE. It was found from the optical absorption spectra that the maximal ab-sorbance of PSI complexes decreased and maximal peaks blue-shifted during the illumination, and the forth derivative spectra demonstrated that the absorbance decreasing at red region mainly resulted from the aborbance decreasing of the long wavelength Chla, implying that the long-wavelength Chla was readily to be bleached. The CD signals contributed by LHCI decreased more rapidly than other CD signals con-tributed by Chla and Carotenoid, indicating that the LHCI was more sensitive to light than core complexes. It was observed by SDS-PAGE that some small polypeptides of PSI complexes were damaged earlier than reaction

The Psb32 Protein Aids in Repairing Photodamaged Photosystem II in the Cyanobacterium Synechocystis 6803

Photosystem II （PSII）, a membrane protein complex, catalyzes the photochemical oxidation of water to molecular oxygen. This enzyme complex consists of approximately 20 stoichiometric protein components. However, due to the highly energetic reactions it catalyzes as part of its normal activity, PSII is continuously damaged and repaired. With advances in protein detection technologies, an increasing number of sub-stoichiometric PSII proteins have been identified, many of which aid in the biogenesis and assembly of this protein complex. Psb32 （SII1390） has previously been identified as a protein associated with highly active purified PSII preparations from the cyanobacterium Synechocystis sp. PCC 6803. To investigate its function, the subcellular localization of Psb32 and the impact of deletion of the psb32 gene on PSII were analyzed. Here, we show that Psb32 is an integral membrane protein, primarily located in the thylakoid membranes. Al- though not required for cell viability, Psb32 protects cells from oxidative stress and additionally confers a selective fitness advantage in mixed culture experiments. Specifically, Psb32 protects PSII from photodamage and accelerates its repair. Thus, the data suggest that Psb32 plays an important role in minimizing the effect of photoinhibition on PSII.

Photodamage to Pigment in the Photosystem Ⅱ Reaction Center D1/D2/Cytochrome b559 Complex

Strong light （800μmol photons/m^2 per s）-induced bleaching of the pigment in the isolated photosystem Ⅱ reaction center （PSII RC） under aerobic conditions （in the absence of electron donors or acceptors） was studied using high-pressure liquid chromatography （HPLC）, absorption spectra, 77K fluorescence spectra and resonance Raman spectra. Changes in pigment composition of the PSII RC as determined by HPLC after light treatment were as follows： with Increasing illumination time chlorophyll （Chl） a and β-carotene （β-car） content decreased. However, decreases in pheophytin （Pheo） could not be observed because of the mixture of the Pheo formed by degraded chlorophyll possibly. On the basis of absorption spectra, it was determined that, with a short time of illuminatlon, the initial bleaching occurred maximally at 680 nm but that with Increasing Illumination time there was a blue shift to 678 nm. It was suggested that P680 was destroyed Initially, followed by the accessory chlorophyll. The activity of P680 was almost lost after 10 mln light treatment. Moreover, the bleaching of Pheo and β-car was observed at the beginning of illumination. After Illumination, the fluorescence emission Intensity changed and the fluorescence maximum blue shifted, showing that energy transfer was disturbed. Resonance Raman spectra of the PSII RC excited at 488.0 and 514.5 nm showed four main bands, peaking at 1 527 cm^-1 （υ101）, 1 159 cm^-1 （υ2）, 1 006 cm^-1 （υ3）, 966 cm^-1 （υ4） for 488.0 nm excitation and 1 525 cm^-1 （υ1）, 1 159 cm^-1 （υ2）, 1 007 cm^-1 （υ3）, 968 cm^-1 （υ4） for 514.5 nm excitation. It was confirmed that two spectroscopically different β-car molecules exist In the PSII RC. After light treatment for 20 mln, band positions and bandwidths were unchanged. This indicates that carotenoid configuration Is not the parameter that regulates photoprotectlon in the PSII RC.

Raman spectroscopic study of DNA photodamage sensitized by hypocrellin B and 5-brominated-hypocrellin B

Hypocrellin B (HB) is a highly effective photosensitizer. One of its derivatives, 5_brominated_hypocrellin B (5_Br_HB) has better photosensitive characteristics than it. Using Raman spectroscopy, the microcosmic photodamage to DNA sensitized by HB and 5_Br_HB was studied at molecular level. The results showed that when HB and 5_Br_HB were added to the solution of DNA and irradiated, the characteristic Raman frequencies and intensities of DNA changed to various degrees. The photodamage occurred on the whole DNA molecule, including phosphate backbone,deoxyribose and four bases. Not only the conformation but also the configuration of DNA was photodamaged: breakage of some H_bonds, disappearance of B_form conformation , scission of double or single strand and serious damage of four bases. The damage to A_T pairs was stronger than that to C_G pairs and DNA became polynucleotides finally. The 5_Br_HB_photosensitized damage to DNA was stronger than HB , which suggested the better photosensitive characteristics of 5_Br_HB in bioactive environment. The molecular mechanisms of photodamage to DNA sensitized by 5_Br_HB and HB were also elucidated.

Baicalin modulates microRNA expression in UVB irradiated mouse skin

This study aimed to evaluate the effects of baicalin on ultraviolet radiation B （UVB）-mediated microRNA （miRNA） expression in mouse skin. We determined miRNA expression profiles in UVB irradiated mice, baicalin treated irradiated mice, and untreated mice, and conducted TargetScan and Gene Ontology analyses to predict miRNA targets. Three miRNAs （mmu-miR-125a-5p, mmu-miR-146a, and mmu-miR-141） were downregulated and another three （mmu-miR-188-5p, mmu-miR-223 and mmu-miR-22） were upregulated in UVB irradiated mice compared with untreated mice. Additionally, these miRNAs were predicted to be related to photocarcinogenesis, hypomethylation and apoptosis. Three miRNAs （mmu-miR-378, mmu-miR-199a-3p and mmu-miR-181b） were downregulated and one （mmu-miR-23a） was upregulated in baicalin treated mice compared with UVB irradiated mice, and they were predicted to be related to DNA repair signaling pathway. These deregulated miRNAs are potentially involved in the pathogenesis of photodamage, and may aid treatment and prevention of UVB-induced dermatoses.

Establishment of Mus Skin Photo-damage Model by 8-MOP plus UVA Irradiation

To establish a simple and reliable animal model of skin photo-damage, 20 mice were treated with 8-MOP and exposed to UVA （UVA 320-400 nm） for 24 h. After irradiation, the structure of the epidermis and dermis, collagen fibers, elastic fibers were observed by using HE staining and Weigert technique and compared with the normal controls. The acanthosis and epidemis proliferation with accompanying hyperkeratosis and parakeratosis were observed. Inflammatory infiltration was noted in the dermis. The elastic fibers became coarse, irregularly arranged and clustered, with their number increased. The collagen fibers showed obvious degeneration and some amorphous materials could also be observed. The blood vessels were irregularly dilated and vascular walls were thickened, with infiltration of inflammatory cells. It is concluded that murine photodamage model can be quickly, conveniently and reliably established by means of 8-MOP/UVA.

Frequency of Benign and Malignant Tumors in Localized Vitiligo in Comparison to Generalized and Universal Vitiligo

Background: Autoimmune diseases like pemphigus and systemic lupus erythematosus are protective against skin malignancies like basal cell carcinoma and squamous cell carcinoma. Objective: As vitiligo is an autoimmune diseases, the aim of the present work is to record the frequency of all benign and malignant skin tumors among patients with different severity of vitiligo and to be compared with the skin tumors in healthy control. Patients and Methods: This is a case series, descriptive study done in the Department of Dermatology—Baghdad Teaching Hospital, Baghdad, Iraq, during the period from May 2014-May 2015. History was taken from each patient with vitiligo regarding age, gender, duration, personal and family history of vitiligo and other autoimmune diseases such as diabetes mellitus, thyroid dysfunction, and alopecia areata. Patients were assessed for past and present history of photodermatosis and any skin cancers. Healthy control was considered. Results: Three hundred and fifty patients with vitiligo were included in this study: 50 patients with universal vitiligo, 100 patients with generalized vitiligo, and 200 patients with localized vitiligo as well as 500 subjects as a healthy control. The ages of all studied subjects ranged between 31 and 77 years. Twenty four(48%) patients with universal vitiligo were males and 26 (52%) were females;49(49%) patients with generalized vitiligo were males and 51(51%) were females;101(50.5%) patients with localized vitiligo were males and 99(49.5%) were females and 235(47%) of control were males and 265(53%) were females. All skin tumors were seen to be high in healthy subjects and lower or absent in patients with vitiligo. Also patients with mild vitiligo had a higher frequency of skin tumors including benign and malignant than patients with severe vitiligo especially in patients with universal vitiligo. In addition, no photosensitivity or actinic reticuloid was detected in patients with vitiligo. Conclusions: Vitiligo especially generalized and universal type as an autoimmune disease had a protective action against photodamage, photosensitivity and skin tumors whether benign or malignant.