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Chronic ultraviolet (UV) exposure may cause skin damage, disrupt skin barrier function, and promote wrinkle formation. UV induces oxidative stress and inflammation, which results in extracellular matrix degradation in the dermis and epidermal hyperplasia. Our previous study demonstrated that fisetin exerts photoprotective activity by inhibiting mitogen-activated protein kinase/activator protein-1/matrix metalloproteinases (MMPs) activation. In this study, fisetin was applied topically to investigate its antiphotodamage effects in hairless mice. The erythema index (a* values) and transepidermal water loss were evaluated to assess skin damage, and immunohistochemical staining was conducted to elucidate the photoprotective mechanism of fisetin. The results revealed that the topical application of fisetin reduced UVB-induced increase in the a* value and wrinkle formation. In addition, fisetin inhibited epidermal hyperplasia and increased the collagen content in the dermis. Fisetin exerted photoprotective activity by inhibiting the expression of MMP-1, MMP-2, and cyclooxygenase-2 and increasing the expression of nuclear factor erythroid 2-related factor. Furthermore, fisetin increased the expression of filaggrin to prevent UVB-induced barrier function disruption. Altogether, the present results provide evidence of the effects and mechanisms of fisetin's antiphotodamage and antiphotoinflammation activities.

Melanin is synthesized through a series of interactions catalyzed by melanogenic enzymes such as tyrosinase, dopachrome tautomerase (tyrosinase-related protein-2; TRP-2), and tyrosinase-related protein-1 (TRP-1). Tyrosinase plays a key role in catalysing the initial and limiting steps of melanogenesis. The melanin that results from melanogenesis has the protective effect of absorbing ultraviolet radiation. However, overproduction of melanin, in addition to altering the appearance of skin, may lead to skin disorders such as melasma, solar lentigo, and postinflammatory hyperpigmentation. Previous studies have revealed that sesamol is a strong antioxidant and a free radical scavenger. In this study, we investigated the effects of sesamol on the regulation of melanogenesis and related mechanisms in B16F10 cells. The results indicated that sesamol inhibited tyrosinase activity and melanogenesis induced by α-melanocyte-stimulating hormone (α-MSH) in B16F10 melanoma cells. Sesamol decreased the protein level of melanocortin 1 receptor (MC1R), microphthalmia-associated transcription factor (MITF), tyrosinase, and TRP-1 by downregulating cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) pathways that had been activated by α-MSH. Sesamol increased glycogen synthase kinase 3 beta (GSK3β), protein kinase B (AKT), and extracellular signal-related kinase (ERK) phosphorylation, thus inhibiting the transcription of MITF. Sesamol also inhibited melanin synthesis and tyrosinase expression by modulating ERK, phosphoinositide 3-kinase (PI3K)/AKT, p38, and c-Jun amino-terminal kinase (JNK) signalling pathways. These results indicate that sesamol acted as a potent depigmenting agent.

Background Recent evidence suggests melasma to be a photoaging disorder. Triple combination creams (TCC: fluocinolone acetonide 0.01%, hydroquinone 4% and tretinoin 0.05%) remain the gold standard treatment. Picosecond alexandrite laser treatment using a diffractive lens array (DLA) has been identified to be effective for improving photoaging conditions. Objective We aimed to compare the efficacy and tolerance of the picosecond alexandrite laser with those of DLA and TCC in female Asian patients with melasma. Methods Twenty‐nine patients were randomly assigned to group A1 (3 laser sessions at 4‐week intervals), A2 (5 laser sessions at 4‐week intervals) or B (TCC daily for at least 8 weeks and then tapered until the final evaluation). The Melasma Area, Severity Index (MASI) score and VISIA were assessed at baseline, week 12 and week 20. By week 20, the follow‐up periods for groups A1 and A2 were 3 months and 1 month, respectively. Results Nine, 11 and 6 participants in groups A1, A2 and B completed the study, respectively. MASI scores were significantly improved in all 3 groups at weeks 12 and 20. In groups A1, A2 and B, the improvement rates at week 20 were 53%, 38% and 50%, respectively. VISIA® analysis additionally revealed a significant improvement in spots, porphyria, pores and brown spots after 3 laser sessions (P < 0.05). Group A2 showed greater improvements than group A1 in terms of spots, wrinkles and pores; however, only red areas were significantly different (P < 0.001). All side‐effects in the 3 groups were transient and gradually subsided after 1–3 months. Conclusion Picosecond alexandrite laser treatment using DLA showed comparable efficacy with TCC for the treatment of melasma. Improvements in texture, spots, wrinkles and pores were observed in the laser groups. Patients with melasma lesions that exhibit telangiectasia may benefit from additional laser treatment sessions.

Depression is one of the most common psychiatric disorders that affects over 10% of individuals. However there is no desirable therapeutic approach nowadays. Thus, looking for an alternative treatment is important. The objectives of this study are to investigate the antidepressant effects of the rhizomes of Gastradia elata B(L), a traditional Chinese medicine, in the animal model forced-swimming test (FST), and to analyze the monoamine content in the rats' brain regions in order to better understand the possible mechanisms of the water extract of the rhizomes of Gastrodia elata B(L) (WGE). Subchronic administration of 0.5 or 1.0 mg/kg bw WGE by gavage for 21 consecutive days significantly reduced the immobility duration of rats in the test session of FST as compared to the control group (p < 0.05), with the equivalent effects as the antidepressant drug fluoxetine. The concentration of serotonin (5-HT) in the frontal cortex and dopamine (DA) in striatum were significantly increased after WGE administration (p < 0.05). The ratio of 5-HIAA/5-HT and (DOPAC + HVA)/DA, i.e. the turnover of 5-HT and DA respectively, were also significantly lowered in WGE groups (p < 0.05). In summary, the present study showed that the WGE possesses antidepressant-like effect on rats in the animal model FST, and the possible mechanism may be via regulating both the serotonergic and dopaminergic systems.

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Ixora parviflora, a species of the Rubiaceae, is rich in polyphenols and flavonoids, and has been traditionally used as a folk medicine. An I. parviflora extract (IPE) has great antioxidant activity in vitro, including a scavenging effect on superoxide radicals, reducing power, and ferrous ion-chelating ability. However, whether IPE is efficacious against oxidative damage in vivo is not known. The purpose of this study was to determine the protective effects of IPE treatment on hepatic oxidative stress and antioxidant defenses after exhaustive exercise in mice. Fifty male C57BL/6 mice (6 week old) were randomly divided into five groups and designated a sedentary control with vehicle (C), and exhaustive exercise with vehicle (IPE0), low dosage (IPE10), medium dosage (IPE50) and high dosage (IPE100) of IPE at 0, 10, 50, and 100 mg/kg, respectively. After a single bout of exhaustive swimming exercise challenge, levels of blood ammonia