Involvement of Aquaporins in the Intense Pulsed Light-Enhanced Wound Healing in Diabetic Rats.

BACKGROUND AND OBJECTIVES: We previously demonstrated that intense pulsed light (IPL) irradiation prior to wounding improved the wound healing in rats with diabetes mellitus (DM). Also, we found that IPL upregulated the expression of aquaporin 3 (AQP3), a protein that is crucial for wound healing, in normal rats. This present study aimed to examine the involvement of AQPs in the IPL-enhanced wound healing in diabetic rats. STUDY DESIGN/MATERIALS AND METHODS: Streptozotocin was used to induce diabetes in Sprague-Dawley rats. Animals were divided into four groups: normal group, DM only group, DM rats with IPL treatment 2 weeks before wounding (DM + IPL-Pre group), and DM rats with concurrent IPL irradiation and wounding (DM + IPL-Con group). Wounds were created on the dorsal skin of rats. The expressions of AQP1, 3, 4, 7, and 9 in the pre-injured skin, periwound, and wound were determined. RESULTS: Among all the AQPs analyzed, only the expressions of AQP3 and AQP7 were significantly altered. Unirradiated diabetic rats showed much higher expression level of AQP3 in the regenerating skin compared with normal rats. IPL pretreatment, but not concurrent treatment, attenuated the expression toward the level detected in the normal wounds. In contrast, a lower expression level of AQP7 was noted in the regenerating skin of DM only rats and IPL pretreatment upregulated the expression to a level similar to that in the normal rats. CONCLUSION: The beneficial effect of IPL pretreatment on the wound healing in diabetic rats might involve a mechanism by which the expression of AQPs is regulated. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Beneficial Effect of Intense Pulsed Light on the Wound Healing in Diabetic Rats.

BACKGROUND AND OBJECTIVE: Wound healing in diabetes mellitus (DM) patients is one of the major health concerns globally. Intense pulsed light (IPL) has been widely used in cosmetic dermatology via mechanisms involving fibroblast stimulation, collagen synthesis, and dermal remodeling, which are events that also occur during the process of wound healing. This present study was aimed to evaluate the possible beneficial effect of IPL on the wound healing in diabetic rats. MATERIALS AND METHODS: Diabetes was induced in Sprague-Dawley rats using streptozotocin. The rats were randomly divided into four groups: normal group, DM only group, DM rats with IPL treatment 2 weeks before wounding (DM + IPL-Pre group), and DM rats with concurrent IPL exposure and wounding (DM + IPL-Con group). The wounds were created on the dorsal skin of rats. Wound closure rate, collagen deposition, and angiogenesis were assessed. RESULTS: There were no significant differences in the wound closure rate and mean time to wound closure between IPL-treated diabetic rats and normal rats. By contrast, delayed wound closure and prolonged mean time to wound closure were both noticed in DM only group. Enhanced collagen deposition and angiogenesis were observed in IPL-Pre, but not IPL-Con diabetic rats, as compared with untreated DM rats. CONCLUSION: Results of this study may provide novel insight into future preventive strategies using IPL for the management of wounds in diabetic patients. Lasers Surg Med. © 2019 Wiley Periodicals, Inc.

Effect of intense pulsed light on the expression of aquaporin 3 in rat skin.

Intense pulsed light (IPL) technology has been popularly employed in clinical treatments for dermatological and cosmetic purposes in recent years; yet, the underlying mechanisms of its functions are not fully elucidated. On the other hand, aquaporin (AQP) 3, a member of a subgroup of the aquaporin family that transports both water and small solutes, such as glycerol, has been documented to play an important role in the skin homeostasis. We thus examined the possible involvement of AQP3 in the functional mechanisms of IPL irradiation. Rat dorsal skin areas were irradiated one to three times with IPL at doses of 15, 25, and 35 J/cm2. Skin specimens were collected 7 days after the final irradiation and analyzed for changes in histology, skin hydration, mRNA, and protein expressions of AQP3. IPL induced no significant variations in the mRNA expression levels. Twice or thrice irradiation at the dose of 25 or 35 J/cm2 significantly enhanced AQP3 protein expression. Immunofluorescence study revealed that AQP3 was mainly localized to keratinocyte membranes in the basal layer of epidermis, and the localization was unaltered by IPL. In addition, the pattern of IPL-induced changes in skin hydration was generally coincided with the expression profile of AQP3. These results suggest the possibility that one of the functional mechanisms of IPL might be related to the regulation of AQP3 protein expression.

Bone and joint protection ability of ceramic material with biological effects.

Ceramic materials with biological effects (bioceramic) have been found to modulate various biological effects, especially those effects involved in antioxidant activity and hydrogen peroxide scavenging. As arthropathy and osteopathy are the major chronic diseases of geriatric medicine, we explored the possible activity of bioceramic on these conditions using animal and cell models. Rabbits received intra-articular injections of lipopolysaccharides (LPS) to induce inflammation that mimic rheumatic arthritis. FDG isotopes were then IV injected for PET scan examinations at 16 hours and 7 days after the LPS injection. We examined and compared the bioceramic and control groups to see if bioceramic was capable of relieving inflammation in the joints by subtracting the final and initial uptake amount of FDG (max SUV). We studied the effects in prostaglandin E2 (PGE2) inhibition on the human chondrosarcoma (SW1353) cell line, and the effects on the murine osteoblast (MC3T3-E1) cell line under oxidative stress. All the subtractions between final and initial uptakes of FDG in the left knee joints of the rabbits after LPS injection indicated larger decreases in the bioceramic group than in the control group. This anti-arthritic or inflammatory effect was also demonstrated by the PGE2 inhibition of the SW1353 cells. We further proved that bioceramic treatment of the MC3T3-E1 cells resulted in increased viability of osteoblast cells challenged with hydrogen peroxide toxicity, and increased alkaline phosphatase activity and the total protein production of MC3T3-E1 cells under oxidative stress. Since LPS-induced arthritis is an experimental model that mimics RA, the potential therapeutic effects of bioceramic on arthropathy merit discussion. Bioceramic may contribute to relieving inflammatory arthritis and maintaining bone health.

Upregulation of NF-E2-related factor-2-dependent glutathione by carnosol provokes a cytoprotective response and enhances cell survival.

AIM: To explore whether glutathione (GSH) increased through Nrf-2 activation is involved in the cytoprotective effects of carnosol in HepG2 cells. METHODS: Human hepatoma cell line HepG2 were exposed to rosemarry essential oil or carnosol. Cell viability was measured using an Alamar blue assay. The production of intracellular GSH was determined using monochlorobimane. The level of protein or mRNA was examined by Western blotting or RT-PCR, respectively. RESULTS: Rosemarry essential oil (0.005%-0.02%) and carnosol (5 and 10 mol/L) increased the intracellular GSH levels and GSH synthesis enzyme subunit GCLC/GCLM expression. Rosemary essential oil and carnosol increased nuclear accumulation of Nrf2 and enhanced Nrf2-antioxidant responsive element (ARE)-reporter activity. Transfection of the treated cells with an Nrf2 siRNA construct blocks GCLC/GCLM induction. Furthermore, pretreatment of the HepG2 cells with essential oil and carnosol exerted significant cytoprotective effects against H(2)O(2) or alcohol. In TNFα-treated cells, the nuclear translocation and transcriptional activity of NF-κB was abolished for 12 h following carnosol pretreatment. Cotreatment with GSH also suppressed NF-κB nuclear translocation, whereas cotreatment with BSO, a GSH synthesis blocker, blocked the inhibitory effects of carnosol. CONCLUSION: This study demonstrated that Nrf2 is involved in the cytoprotective effects by carnasol, which were at least partially mediated through increased GSH biosynthesis.

Neural mechanisms involved in the oral representation of percussion music: an fMRI study.

Numerous music cultures use nonsense syllables to represent percussive sounds. Covert reciting of these syllable sequences along with percussion music aids active listeners in keeping track of music. Owing to the acoustic dissimilarity between the representative syllables and the referent percussive sounds, associative learning is necessary for the oral representation of percussion music. We used functional magnetic resonance imaging (fMRI) to explore the neural processes underlying oral rehearsals of music. There were four music conditions in the experiment: (1) passive listening to unlearned percussion music, (2) active listening to learned percussion music, (3) active listening to the syllable representation of (2), and (4) active listening to learned melodic music. Our results specified two neural substrates of the association mechanisms involved in the oral representation of percussion music. First, information integration of heard sounds and the auditory consequences of subvocal rehearsals may engage the right planum temporale during active listening to percussion music. Second, mapping heard sounds to articulatory and laryngeal gestures may engage the left middle premotor cortex.