IL-17 induces cellular stress microenvironment of melanocytes to promote autophagic cell apoptosis in vitiligo.

Vitiligo is a depigmentary disorder that develops as a result of the progressive disappearance of epidermal melanocytes. Stress can precipitate or exacerbate a skin disease through psychosomatic mechanisms. Stress exposure induces vitiligo-like symptoms in mice, as cellular damage to melanocytes causes synthetic pigment loss. Stress also increases IL-17, IL-1ß, and antimelanocyte IgG in model mouse serum. Up-regulation of the IL-1ß transcript in patients suggests its possible role in autoimmune pathogenesis of vitiligo. We demonstrate that IL-17 promoted IL-1ß secretion from keratinocytes. Mitochondrial dysfunction, which can induce the excessive production of reactive oxygen species (ROS), is emerging as a mechanism that underlies various inflammatory and autoimmune diseases. In this study, we demonstrate that IL-17 inhibits melanogenesis of zebrafish, normal human epidermal melanocytes, and B16F10 cells. IL-17 increased mitochondrial dysfunction and ROS accumulation, which was related to autophagy induction. Autophagy is needed for autophagic apoptosis of B16F10 cells induced by IL-17. To inhibit ROS generation, B16F10 cells were pretreated with N-acetyl-l-cysteine (NAC), which inhibited autophagy. 3-Methyladenine (3-MA) also had an inhibiting effect on autophagy. NAC or 3-MA pretreatments inhibited IL-17-mediated cell apoptosis. In summary, IL-17 induces the cellular stress microenvironment in melanocytes to promote autophagic cell apoptosis in vitiligo.-Zhou, J., An, X., Dong, J., Wang, Y., Zhong, H., Duan, L., Ling, J., Ping, F., Shang, J. IL-17 induces cellular stress microenvironment of melanocytes to promote autophagic cell apoptosis in vitiligo.

Metabolomics Characterizes the Effects and Mechanisms of Quercetin in Nonalcoholic Fatty Liver Disease Development.

As metabolomics is widely used in the study of disease mechanisms, an increasing number of studies have found that metabolites play an important role in the occurrence of diseases. The aim of this study is to investigate the effects and mechanisms of quercetin in high-fat-sucrose diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) development using nontargeted metabolomics. A rat model of NAFLD was established by feeding with an HFD for 30 and 50 days. The results indicated quercetin exhibited hepatoprotective activity in 30-day HFD-induced NAFLD rats by regulating fatty acid related metabolites (adrenic acid, etc.), inflammation-related metabolites (arachidonic acid, etc.), oxidative stress-related metabolites (2-hydroxybutyric acid) and other differential metabolites (citric acid, etc.). However, quercetin did not improve NAFLD in the 50-day HFD; perhaps quercetin was unable to reverse the inflammation induced by a long-term high-fat diet. These data indicate that dietary quercetin may be beneficial to NAFLD in early stages. Furthermore, combining metabolomics and experimental approaches opens avenues to study the effects and mechanisms of drugs for complex diseases.

Characterization of the volatile profile and its estrogenic activity in Kadsura coccinea fruit.

ETHNOPHARMACOLOGICAL RELEVANCE: The fruit of Kadsura coccinea (Lem.) A. C. Smith is an ethnomedicine used to treat abnormal menstruation, menopausal syndrome, and female infertility among the Dong Nationality in China. AIM OF THE STUDY: Our study aimed to identify the volatile oil profiles of the K. coccinea fruit and elucidate their estrogenic activity. MATERIALS AND METHODS: The peel volatile oil (PeO), pulp volatile oil (PuO), and seed volatile oil (SeO) of K. coccinea were extracted using hydrodistillation and qualitatively analyzed using gas chromatography-mass spectrometry (GC-MS). Estrogenic activity was evaluated in vitro using cell assay and in vivo using immature female rats. Serum 17ß-Estradiol (E2) and follicle-stimulating hormone (FSH) levels were detected using ELISA. RESULTS: In total, 46 PeO, 27 PuO, and 42 SeO components representing 89.96%, 90.19%, and 97% of the total composition, respectively, were identified. The compounds with the highest content in PeO, PuO, and SeO were ß-caryophyllene, γ-amorphene, and n-hexadecanoic acid, respectively. PeO induced proliferation of MCF-7 cells with an EC50 of 7.40 µg/mL. Subcutaneous administration of 10 mg/kg PeO significantly increased the weight of the uteri in immature female rats, with no effect on serum E2 and FSH levels. PeO acted as an agonist of ERα and ERß. PuO and SeO showed no estrogenic activity. CONCLUSION: The chemical compositions of PeO, PuO, and SeO of K. coccinea are different. PeO is the main effective fraction for estrogenic activities, providing a new source of phytoestrogen for the treatment of menopausal symptoms.

Traditional Tibetan medicine Anzhijinhua San attenuates ovalbumin-induced diarrhea by regulating the serotonin signaling system in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Tibetan medicine has been practiced for 3800 years. Anzhijinhua San (AZJHS), which is a traditional Tibetan medicine, has been effective in the treatment of indigestion, anorexia and cold diarrhea. However, the effects of AZJHS on allergic diarrhea have not been reported. AIM OF THE STUDY: The aim of the present study was to elucidate the effect of AZJHS on experimental ovalbumin-induced diarrhea and elucidate its possible mechanism. MATERIALS AND METHODS: Female BALB/c mice were sensitized by intraperitoneal injection with 50 µg ovalbumin (OVA) and 1 mg alum in saline twice during a 2-week period. From day 28, mice were orally challenged with OVA (50 mg) every other day for a total of ten times. AZJHS (46.8 and 468.0 mg/kg) was orally administered every other day from day 0-46. Food allergy symptoms were evaluated. OVA- specific IgE, 5-HT and its metabolites in serum were determined. Immunohistochemical and histopathology were performed in gastrointestinal tract tissues. 5-HT-related gene expression was assayed in the colon. RESULTS: Severe symptoms of allergic diarrhea were observed in the model group (diarrhea, anaphylactic response, and rectal temperature). AZJHS (46.8 and 468.0 mg/kg) significantly reduced mouse diarrhea and significantly prevented the increases in OVA-specific IgE levels (P < 0.05), which challenge with OVA. AZJHS (46.8 and 468.0 mg/kg) significantly prevented the increases in 5-HT-positive cells. The nuclei of EC cells in the AZJHS (46.8 and 468.0 mg/kg) group increased in size and the secretory granules were fewer in number compared with those in the model group. AZJHS (46.8 and 468.0 mg/kg) significantly increased the relative fold changes of 5-HTP and 5-HT compared with the model group. The mRNA expression of the serotonin transporter (Sert) and serotonin receptor 3A (Htr3a) was significantly decreased after the 10th challenge with OVA, and AZJHS (46.8 and 468.0 mg/kg) significantly increased these levels. CONCLUSIONS: We demonstrated that the administration of AZJHS attenuated OVA-induced diarrhea by regulating the serotonin pathway. These results indicated that AZJHS may be a potential candidate as an anti-allergic diarrhea agent.

[Metabolic analysis of serotonin system in serum and gastric tissues of ovalbumin-induced allergic mice].

Objective To investigate the changes of 5-HT (serotonin) signaling system in allergic diarrhea mice sensitized with ovalbumin (OVA). Methods The seven-to-eight-week-old BALB/c female mice were randomly divided into model group, sodium chromate group and negative control group. The model group and sodium chromate group were intraperitoneally injected with OVAI (50 µg per mouse) at day 0 and day 14 respectively. And starting from the 28th day, OVAII was orally administered (50 mg per mousee) every other day (8 times in total), and the sodium chromate group was given the sodium chromate (78.0 mg/kg) before the oral administration of OVA every other day (8 times in total). The allergic symptoms, including the systemic score, faeces score and body temperature were recorded following the OVA administration for sensitization. The mice were executed 43 days later. Eyeball blood sample was collected, and then serum was seperated by centrifugation, the gastric tissues was taken out. The serum OVA-specific IgE (OVA-SIgE) was detected by ELISA. The serum content of 5-HT and its related metabolites including kynurenine (KYN), tryptophan (TRP), 5-hydroxytryptophan (5-HTP), and 5-hydroxyindoleacetic acid (5-HIAA) were examined by liquid chromatography-mass spectrometry (LC-MS). The mRNA levels of tryptophan hydroxylase-1 (TPH1), indolamine-2, 3-dioxygenase 1 (IDO1), monoamine oxidase A (MAO-A), 5-hydroxytryptamine 1A receptor (HTR1A), 5-hydroxytryptamine 3 receptor (HTR3), 5-hydroxytryptamine 4 receptor (HTR4) and serotonin reuptake transporter (SERT) were determined by real-time quantitative PCR. Results OVA sensitization caused severe allergic diarrhea in mice. Serum OVA-SIgE increased significantly in mice sensitized by OVA. serum KYN increased remarkably, while 5-HT, 5-HIAA and 5-HTP decreased significantly. The mRNA levels of IDO1, HTR1A and HTR3A increased in gastric tissues, while the levels of TPH1 and MAO-A mRNA decreased. Compared with the model group, the sodium chromate group had lowed systemic score, faeces score, body temperature and OVA-SIgE as well as diarrhea rate. The mRNA levels of 5-HIAA and MAO-A increased in the gastric tissues, and IDO1, 5-HT1A and 5-HT3A mRNAs decreased in the sodium chromate group. Conclusion The serotonin signaling system in ovalbumin-sensitized allergic diarrhea mice has been activated. The administration of sodium chromate can alleviate the allergic symptoms, and change the levels of serum metabolites and the gene expressions of the 5-HT metabolic pathway and its receptors in the stomach.

Interleukin-22 participates in the inflammatory process of vitiligo.

Vitiligo is an acquired depigmentary skin inflammatory disorder. The pathogenesis of inflammatory skin disease involves the release of cytokines from keratinocytes, including interleukin (IL)-1ß. IL-22 belongs to a family of cytokines structurally related to IL-10, including IL-19, IL-20, IL-24, and IL-26. In contrast to IL-10, IL-22 has proinflammatory activities. Among skin cell populations only keratinocytes are the major targets of IL-22. In the present study, we demonstrated that IL-22 promoting IL-1ß secretion from keratinocytes via the Reactive oxygen species (ROS)-NOD-like receptor family, pyrin domain containing 3 (NLRP3)-caspase-1 pathway. It inhibited the expression of protease-activated receptor-2 (PAR-2) of keratinocytes. However, IL-22 had no direct effect on normal human foreskin-derived epidermal melanocytes (NHEM). Considering the closely connection between keratinocytes and melanocytes, and the ability of keratinocytes to produce a plethora of cytokines, in the present work, we examined whether IL-22 could regulate melanocytes functions by keratinocytes participation. Keratinocytes were exposed to IL-22 and the conditional medium was collected. The effect of conditional medium on melanocytes was studied. The expressions of relative proteins were assessed by western blot. Influence of conditional medium on NHEM migration was assessed by Transwell method and the apoptosis by flow cytometry analysis. The IL-22-treating keratinocytes conditional medium inhibited melanogenesis and restrained the expressions of Rab GTPases of NHEM. In addition, the conditional medium suppressed melanocytes migration and induced apoptosis. Our results collectively indicated that IL-22 may potentiate IL-1ß-mediated skin inflammation and result in participating in the inflammatory pathogenesis of vitiligo.