Psoriasis is a chronic inflammatory skin disease, and its pathogenesis is largely modulated by abnormal angiogenesis. Previous research has indicated that AlkB homolog 5 (ALKBH5), an important demethylase affecting N⁶-methyladenosine (m⁶A) modification, plays a role in regulating angiogenesis in cardiovascular and eye diseases. Our present study found that ALKBH5 was upregulated and co-localized with cluster of differentiation 31 (CD31) in the skin of IMQ group compared with control group. ALKBH5-deficient mice decreased IMQ-induced psoriatic dermatitis and exhibited histological improvements, including decreased epidermal thickness, hyperkeratosis, numbers of dermal capillary vessels and inflammatory cell infiltration. ALKBH5-KO mice alleviated angiogenesis in psoriatic lesions by downregulating the protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway. Additionally, the expression of ALKBH5 was significantly upregulated in IL-17A-induced human umbilical vein endothelial cells (HUVECs), which further promoted the expression of angiogenesis-related cytokines and endothelial cell proliferation. Cell proliferation and angiogenesis were suppressed in ALKBH5 knockdown group, whereas ALKBH5 overexpression promoted these processes. The regulation of angiogenesis in HUVECs by ALKBH5 was facilitated through the AKT-mTOR pathway. Collectively, ALKBH5 plays a pivotal role in psoriatic dermatitis and angiogenesis, which may offer a new potential targets for treating psoriasis.
Animals ; Psoriasis/chemically induced* ; Mice ; Humans ; Neovascularization, Pathologic/genetics* ; Human Umbilical Vein Endothelial Cells/metabolism* ; AlkB Homolog 5, RNA Demethylase/genetics* ; Proto-Oncogene Proteins c-akt/metabolism* ; TOR Serine-Threonine Kinases/metabolism* ; Cell Proliferation ; Mice, Knockout ; Disease Models, Animal ; Signal Transduction ; Male ; Skin/blood supply* ; Mice, Inbred C57BL ; Angiogenesis

Objective: To investigate the effects of RNA m6A demethylase ALKBH5 gene deficiency on cerebellar morphology and function in the aged mice, and to explore the role of ALKBH5 in cerebellar degeneration. Methods: Western blot was performed to detect the protein level of ALKBH5 in the cerebellum of wild-type mice of various ages. The expression of NeuN, Calbindin-D28K, MAP2, GFAP and other proteins in the cerebella of middle-aged (12-month-old) and aged (18-month-old) wild-type mice and ALKBH5^-/- mice was examined using immunohistochemistry. The balance beam test and gait analysis were performed to test the balance ability and motor coordination of the mice. Results: With aging of the mice, the expression of ALKBH5 in the cerebellum increased gradually in an age-dependent manner. In the aged mice, but not middle-aged mice, the body weight, whole brain weight and cerebellum weight of ALKBH5^-/- mice decreased by 15%, 10% and 21%, respectively (P<0.05). The expression of ALKBH5 in the Purkinje cells was much higher than that in other types of neural cells. Correspondingly, ALKBH5-deficiency caused 40% reduction in the number of Purkinje cells, as well as the length and density of neuronal dendrites in the aged mice (P<0.01). In addition, the time for the aged ALKBH5^-/- mice to pass the balance beam was 70% longer than that of the wild type mice of the same age, with unstable gaits (P<0.01). Conclusions: Gene deficiency of RNA m6A demethylase ALKBH5 causes cerebellar atrophy, Purkinje neuron loss and damage in the aged mice. These changes eventually affect mice's motor coordination and balance ability. These results suggest that imbalanced RNA m6A methylation may lead to neurodegenerative lesions in the cerebellum of mice.
Animals ; Mice ; AlkB Homolog 5, RNA Demethylase/metabolism* ; Cerebellum/metabolism* ; Methylation ; RNA/metabolism*

OBJECTIVE: To investigate the effects of ALKBH5 on migration, invasion and epithelial-mesenchymal transition (EMT) of human trophoblast cells. METHODS: The expression plasmid of ALKBH5 or a negative control plasmid (ALKBH5-NC) was transfected in human trophoblast HTR-8 /SVneo cells, and the expressions of ALKBH5 mRNA and protein were detected by qRT-PCR and Western blotting. Transwell assay was used to assess the changes in migration and invasion abilities of the trophoblast cells after the transfection. Western blotting was performed to detect the expressions of EMT-related proteins in the cells including vimentin, fibronectin, E-cadherin, N-cadherin, MMP9 and MMP2. RESULTS: ALKBH5 mRNA and protein expressions were significantly higher in ALKBH5 group than in the control group ( CONCLUSIONS ALKBH5 is involved in the pathogenesis of preeclampsia by inhibiting EMT of trophoblast cells and hence reducing their migration and invasion abilities.
AlkB Homolog 5, RNA Demethylase ; Cell Line, Tumor ; Cell Movement ; Epithelial-Mesenchymal Transition ; Female ; Humans ; Pre-Eclampsia ; Pregnancy ; Trophoblasts ; Vimentin/genetics*