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Objective:To investigate the effect of miRNA (miR) -193b-5p on melanogenesis and its possible mechanisms.Methods:Human primary melanocytes were isolated from discarded normal foreskin tissues of healthy males after circumcision, and cultured in vitro. miR-NC mimics (miR-NC mimic group) and miR-193b-5p mimics (miR-193b-5p mimic group) were transfected into human primary melanocytes and human MNT1 melanoma cells, separately. After transfection, real-time quantitative PCR (RT-qPCR) was performed to determine the overexpression efficiency of miR-193b-5p at 48 hours, Western blot analysis to determine the expression of melanogenesis-related proteins tyrosinase (TYR) and microphthalmia-associated transcription factor (MITF) in human primary melanocytes and human MNT1 melanoma cells at 72 hours, and the melanin content in the above cells was determined by a sodium hydroxide solubilization method at 1 week. The target gene of miR-193b-5p was predicted by using Targetscan algorithms and verified by dual-luciferase reporter assay, and RT-qPCR and Western blot analysis were performed to analyze changes in mRNA and protein expression of the target gene respectively after the overexpression of miR-193b-5p. Two-independent-samples t test was used for comparisons between two groups. Results:In human primary melanocytes and human MNT1 melanoma cells, the miR-193b-5p expression levels were significantly higher in the miR-193b-5p mimic groups than in the miR-NC mimic groups ( t = 65.57, 22.49, respectively, both P < 0.001) , and the melanin content was significantly lower in the miR-193b-5p mimic groups (0.091 ± 0.007, 0.130 ± 0.004, respectively) than in the miR-NC mimic groups (0.117 ± 0.002, 0.188 ± 0.032, t = 5.98, 3.24, P < 0.01, < 0.05, respectively) . Western blot analysis showed that the expression of melanogenesis-related proteins TYR and MITF in both human primary melanocytes and human MNT1 melanoma cells was significantly lower in the miR-193b-5p mimic groups than in the miR-NC mimic groups (all P < 0.01) . TargetScan analysis and dual-luciferase reporter assay revealed a binding site for miR-193b-5p in the 3′ untranslated region of the transcriptional regulator CITED2. After up-regulation of miR-193b-5p expression in human primary melanocytes and human MNT1 melanoma cells, the CITED2 mRNA and protein expression levels significantly decreased compared with the miR-NC mimic groups (all P < 0.05) . Conclusion:miR-193b-5p overexpression can down-regulate the expression of melanogenesis-related proteins TYR and MITF, and then inhibit melanogenesis, which may be related to the targeted inhibition of CITED2 expression.
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Objective:To explore the effect of self-esteem and sibling relationships on the links of parental cohesion and internalizing problems in junior high school students based on the family system theory.Methods:A total of 565 junior high school students were investigated with the sibling relationship questionnaire, parent-child cohesion questionnaire, self-esteem scale and internalizing problems questionnaire from April to June 2021.SPSS 26.0 was used for descriptive statistics and Pearson correlation analysis.PROCESS was used to examine the mediating and moderating effect.Results:Maternal-child cohesion was positively correlated with self-esteem and sibling warmth ( r=0.36, 0.58, both P<0.01), while it was negatively correlated with internalizing problems and sibling conflict ( r=-0.29, -0.25, both P<0.01). Similarly, paternal-child cohesion was positively correlated with self-esteem and sibling warmth ( r=0.37, 0.51, both P<0.01), and it was negatively correlated with internalizing problems and sibling conflict ( r=-0.36, -0.21, both P<0.01). The self-esteem played a partial mediating role between maternal-child cohesion and internalizing problems ( β=-0.09, 95% CI=-0.14--0.05), and the mediating value was 30.13%.The self-esteem also played a partial mediating role between paternal-child cohesion and internalizing problems ( β=-0.07, 95% CI=-0.11--0.04), and the mediating value was 25.36%.Sibling warmth could improve the positive effect of maternal-child cohesion on self-esteem ( β=0.06, 95% CI=0.01-0.11), while could offset the negative effects of low level of maternal-child cohesion against the internalizing problems ( β=0.10, 95% CI=0.04-0.16). But sibling conflict did not significantly predict the effects of maternal-child cohesion on self-esteem and internalizing problems.Similarly, sibling warmth could improve the positive effect of paternal-child cohesion on self-esteem ( β=0.05, 95% CI=0.01-0.09), while could offset the negative effects of low level of paternal-child cohesion against the internalizing problems ( β=0.09, 95% CI=0.03-0.15). But sibling conflict could reduce the positive impact of paternal-child cohesion and self-esteem ( β=-0.05, 95% CI=-0.09--0.01), while had no effect on the impact of paternal-child cohesion and internalizing problems. Conclusion:Parent-child cohesion not only directly affects the internalizing problems, but also indirectly affects the internalizing problems through the self-esteem.Positive parent-child cohesion and sibling warmth relationships can improve the individual's self-esteem level and reduce the internalizing problems.
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Objective To evaluate effects of a fusion protein LTβR-Fc, which can block the herpesvirus entry mediator ligand (LIGHT-HVEM)signaling pathway, on ovalbumin-induced dermatitis in a mouse model. Methods Thirty BALB/c mice were randomly and equally divided into 3 groups: blank control group treated with 100 μl of sodium chloride physiological solution, model group sensitized with 100 μl of sodium chloride physiological solution containing 100 μg ovalbumin, blocker group firstly blocked with 100 μl of sodium chloride physiological solution containing 100 μg LTβR-Fc followed by sensitization with 100 μl of sodium chloride physiological solution containing 100 μg ovalbumin at 24 hours after the blocking. Disease severity was evaluated by eczema area and severity index (EASI)score, and lesional size was measured on day 0, 4, 8, 12, 15, 20, 23, 27, 31 and 34 after the first sensitization. A total of three sessions of sensitization were carried out. At the end of treatment, all the mice were sacrificed after serum was obtained from their orbital cavities. Thereafter, tissue specimens were obtained from skin lesions, and single cell suspensions of the spleen were prepared. RT-PCR was performed to detect mRNA expressions of interferon γ (IFN-γ), interleukin 4 (IL-4)and IL-5 in murine lesions, ELISA to measure IFN-γ, IL-4 and IL-5 levels in culture supernatants of murine splenocytes, as well as ovalbumin-specific and total IgE and IgG1 levels in murine sera. Results LTβR-Fc significantly suppressed inflammatory response in the mouse model of dermatitis induced by ovalbumin. Compared with the model group, the blocker group showed significantly decreased lesion area and EASI score (both P < 0.05). In addition, a significant decrease was observed in the mRNA expressions of IL-4 (0.88 ± 0.25 vs. 1.81 ± 0.25, P < 0.05), IL-5 (0.75 ± 0.15 vs. 1.24 ± 0.26, P < 0.05)and IFN-γ (0.62 ± 0.09 vs. 1.11 ± 0.19, P < 0.05)in murine lesions, and in supernatant levels of IL-4 (9.58 ± 1.44 ng/L vs. 20.12 ± 5.39 ng/L, P < 0.05), IL-5 (11.37 ± 2.02 ng/L vs. 22.77 ± 4.07 ng/L, P < 0.05)and IFN-γ (16 167 ± 950.40 ng/L vs. 23 930 ± 44.20 ng/L, P < 0.05)in the blocker group compared with the model group. The serum levels of both total IgE and ovalbumin-specific IgE were significantly lower in the blocker group than in the model group(total IgE: 27 466.67 ± 2 052.64 μg/L vs. 32 277 ± 407.53 μg/L, P < 0.05; ovalbumin-specific IgE: 1 296.33 ± 32.72 μg/L vs. 2 323.33 ± 502.43 μg/L, P < 0.05), so were those of total IgG1 (0.46 ± 0.11 μg/L vs. 0.84 ± 0.11 μg/L, P < 0.05)and ovalbumin-specific IgG1 (0.62 ± 0.11 μg/L vs. 0.86 ± 0.07 μg/L, P < 0.05). Conclusion The fusion protein LTβR-Fc can alleviate symptoms of ovalbumin-induced dermatitis in the mouse model likely by suppressing the LIGHT-HVEM signaling pathway, suggesting that this signaling pathway may serve as a target for the treatment of dermatitis(such as atopic dermatitis).