Genome-Wide Analysis of mRNA and Long Noncoding RNA Profiles in Chronic Actinic Dermatitis.

Chronic actinic dermatitis (CAD), a photosensitive dermatosis, is characterized by inflammatory lesions, especially on sun-exposed skin. However, its pathogenesis remains unclear. In this study, second-generation RNA sequencing and comprehensive bioinformatics analyses of mRNAs and long noncoding RNAs (lncRNAs) were performed to determine the transcriptome profiles of patients with CAD. A total 6889 annotated lncRNAs, 341 novel lncRNAs, and 65091 mRNAs were identified. Interestingly, patients with CAD and healthy controls showed distinct transcriptome profiles. Indeed, 198 annotated (81.48%) and 45 novel (18.52%) lncRNAs were differentially expressed between the two groups. GO, KEGG, and RGSEA analyses of lncRNAs showed that inflammatory and immune response related pathways played crucial roles in the pathogenetic mechanism of CAD. In addition, we unveiled key differentially expressed lncRNAs, including lncRNA RP11-356I2.4 which plays a role probably by regulating TNFAIP3 and inflammation. qRT-PCR data validated the differentially expressed genes. The newly identified lncRNAs may have potential roles in the development of CAD; these findings lay a solid foundation for subsequent functional exploration of lncRNAs and mRNAs as therapeutic targets for CAD.

The first anionic defensin from amphibians.

A variety of antimicrobial peptides against infection have been identified from the skin of amphibians. However, knowledge on amphibian defensins is very limited. A novel anionic defensin designated PopuDef was purified from the skin of tree frog Polypedates puerensis, and the cDNA encoding PopuDef precursor was cloned from the skin cDNA library. The amino acid sequence of PopuDef (net charge: -2, pI: 4.75) shared the highest identity of 57 % (25/44) with the salamander defensin CFBD-1 (net charge: 0, pI: 6.14) from urodela amphibians. PopuDef showed moderate antimicrobial activities against P. aeruginosa and S. aureus (MICs are 19.41 and 17.25 µM, respectively), and relatively weak activities against E. coli and B. subtilis (MICs are 38.82 and 43.14 µM, respectively). Tissue distribution analysis indicated that relatively high expression level of PopuDef mRNA was observed in immune-related tissues including skin, gut, lung and spleen. Furthermore, the expression level of PopuDef was significantly upregulated in these tissues after tree frogs were infected with different bacteria strains mentioned above. Interestingly, the induction of PopuDef challenged with E. coli or B. subtilis, which was less sensitive to PopuDef, was much higher than that did with P. aeruginosa or S. aureus. These findings highlight the key role of PopuDef in innate immunity against infection. To our knowledge, PopuDef is the first anionic defensin characterized from amphibians.

[Sexual dimorphisms of dopaminergic neurons in rat substantia nigra].

There are sex differences in some brain areas in mammalians. Parkinson's disease (PD), caused by the mesencephalic substantia nigra (SN) dopaminergic neuronal loss, displays sexual difference, i.e., the incidence is higher and the symptoms are more intense in males than that in females. However, it has not been known whether sexual dimorphisms exist in the SN. Sixty adult Sprague-Dawley rats were randomly divided into 5 groups: (1) Female intact group (F-INT group); (2) Male intact group (M-INT group); (3) Ovariectomized group (OVX group); (4) Castration group (CAST group); (5) Ovariectomized + estrogen-replaced group (OVX-E(2) group): The rats received sequentially physiological dose of estrogen for 3 d from the 7th day after ovariectomization. P50 auditory evoked potential (P50) was recorded for 14 d from electrodes inserted in the rat right SN in quiet and awake state. After recording, the brain tissues were dissected and the tyrosine hydroxylase (TH)-expressing neurons in the compact zone of the SN were counted using immunohistochemical method. The results showed that the number of TH-positive (TH(+)) cells in the SN of normal male animals was less than that in normal female rats (P<0.05), and the T/C ratio of P50 in normal males was significantly less than that in normal females (P<0.01), indicating that there exists sexual difference in function and structure in the SN. No differences in the T/C ratio of P50 or the number of TH(+) cells were found between M-INT and CAST groups. The T/C ratio of P50 and the number of TH(+) cells in the SN in OVX group were reduced significantly compared with those in F-INT group (P<0.01). There was no significant difference in the T/C ratio of P50 and the number of TH(+) cells in the SN between OVX- E(2) and F-INT groups 15-20 d after estrogen replacement, suggesting that estrogen can promote the survival and functional recovery of dopaminergic neurons in the SN. The results suggest that there exist sex-specific differences in the dopaminergic neurons in the SN structurally and functionally. The difference of estrogen level in cerebra between male and female animals may account for the sexual differences. Endogenous estrogen plays an important role in maintaining the integrity and modulating the functional activity of dopamine system in the SN.