N-n-Butyl haloperidol iodide ameliorates liver fibrosis and hepatic stellate cell activation in mice

N-n-Butyl haloperidol iodide (F₂) is a novel compound that has antiproliferative and antifibrogenic activities. In this study we investigated the therapeutic potential of F₂ against liver fibrosis in mice and the underlying mechanisms. Two widely used mouse models of fibrosis was established in mice by injection of either carbon tetrachloride (CCl₄) or thioacetamide (TAA). The mice received F₂ (0.75, 1.5 or 3 mg·kg^-1·d^-1, ip) for 4 weeks of fibrosis induction. We showed that F₂ administration dose-dependently ameliorated CCl₄- or TAA-induced liver fibrosis, evidenced by significant decreases in collagen deposition and c-Jun, TGF-β receptor II (TGFBR2), α-smooth muscle actin (α-SMA), and collagen I expression in the liver. In transforming growth factor beta 1 (TGF-β1)-stimulated LX-2 cells (a human hepatic stellate cell line) and primary mouse hepatic stellate cells, treatment with F₂ (0.1, 1, 10 μM) concentration-dependently inhibited the expression of α-SMA, and collagen I. In LX-2 cells, F₂ inhibited TGF-β/Smad signaling through reducing the levels of TGFBR2; pretreatment with LY2109761 (TGF-β signaling inhibitor) or SP600125 (c-Jun signaling inhibitor) markedly inhibited TGF-β1-induced induction of α-SMA and collagen I. Knockdown of c-Jun decreased TGF-β signaling genes, including TGFBR2 levels. We revealed that c-Jun was bound to the TGFBR2 promoter, whereas F₂ suppressed the binding of c-Jun to the TGFBR2 promoter to restrain TGF-β signaling and inhibit α-SMA and collagen I upregulation. In conclusion, the therapeutic benefit of F₂ against liver fibrosis results from inhibition of c-Jun expression to reduce TGFBR2 and concomitant reduction of the responsiveness of hepatic stellate cells to TGF-β1. F₂ may thus be a potentially new effective pharmacotherapy for human liver fibrosis.

Inhibition of the PI3K-Akt-mTOR signaling pathway in T lymphocytes in patients with active tuberculosis

OBJECTIVES

To investigate PI3K-Akt-mTOR signaling pathway changes and the proliferation of FoxP3⁺T_reg cells in patients with active tuberculosis.

METHODS

We isolated PBMCs and CD4⁺CD25⁺FoxP3⁺T_reg cells from peripheral blood collected from patients with active tuberculosis and healthy controls. We compared the proportion and MFI of PI3K-Akt-mTOR pathway components and PTEN by flow cytometry using specific cell-surface and intracellular markers. Moreover, we detected the specific secretory proteins ESAT-6 and Ag85B, cytokines IL-10, TGF-β1 and IL-35 in serum by ELISA.

RESULTS

Compared with healthy controls, the proportions of CD3⁺Akt⁺, CD3⁺p-Akt⁺, CD3⁺mTOR⁺, CD3⁺p-mTOR⁺ and CD3⁺PTEN⁺ cells, in the T lymphocyte population of patients with active tuberculosis, were decreased (p<0.05), while CD3⁺FoxP3⁺ cells were increased (p=0.013). Similarly, for CD4⁺CD25⁺FoxP3⁺T_reg cells, the proportions of Akt⁺ cells, p-Akt⁺ cells, mTOR⁺ cells, p-mTOR⁺ cells and PTEN⁺ cells were decreased (p<0.05) in patients with active tuberculosis. Compared with healthy controls, the levels of ESAT-6 and Ag85B were higher in patients with active tuberculosis (p<0.001). Levels of IL-10 and TGF-β1 were higher (p<0.001), whereas the level of IL-35 was lower (p<0.001).

CONCLUSION

The PI3K-Akt-mTOR signaling pathway in T lymphocytes and CD4⁺CD25⁺FoxP3⁺T_reg cells was inhibited, which could explain why M.tuberculosis can induce FoxP3⁺T_reg cell to expand.

Canonical and non-canonical Wnt signaling control the regeneration of amputated rodent vibrissae follicles

Although mammals are notoriously poor at regeneration compared with many lower-order species, the hair follicle, particular to mammals, is capable of regeneration following partial amputation. The detailed internal mechanism of this phenomenon is still unclear. Development and regrowth of the hair follicle depends on dermal-epidermal interaction within the hair follicle. Previous studies have shown that Wnt/β-catenin, Shh, Bmp, PDGF, TGF and Notch signals all take part in the development and growth of the hair follicle, and the Wnt/β-catenin signaling additionally plays an indispensable role in hair follicle morphogenesis and regrowth. In this study, we investigated the localization, as well as, protein levels of Wnt/β-catenin signaling molecules during amputated whisker follicle regeneration.

iTRAQ-Based Quantitative Proteomic Comparison of Early- and Late-Passage Human Dermal Papilla Cell Secretome in Relation to Inducing Hair Follicle Regeneration

Alopecia is an exceedingly prevalent problem that lacks effective therapy. Recently, research has focused on early-passage dermal papilla cells (DPCs), which have hair inducing activity both in vivo and in vitro. Our previous study indicated that factors secreted from early-passage DPCs contribute to hair follicle (HF) regeneration. To identify which factors are responsible for HF regeneration and why late-passage DPCs lose this potential, we collected 48-h-culture medium (CM) from both of passage 3 and 9 DPCs, and subcutaneously injected the DPC-CM into NU/NU mice. Passage 3 DPC-CM induced HF regeneration, based on the emergence of a white hair coat, but passage 9 DPC-CM did not. In order to identify the key factors responsible for hair induction, CM from passage 3 and 9 DPCs was analyzed by iTRAQ-based quantitative proteomic technology. We identified 1360 proteins, of which 213 proteins were differentially expressed between CM from early-passage vs. late-passage DPCs, including SDF1, MMP3, biglycan and LTBP1. Further analysis indicated that the differentially-expressed proteins regulated the Wnt, TGF-β and BMP signaling pathways, which directly and indirectly participate in HF morphogenesis and regeneration. Subsequently, we selected 19 proteins for further verification by multiple reaction monitoring (MRM) between the two types of CM. These results indicate DPC-secreted proteins play important roles in HF regeneration, with SDF1, MMP3, biglycan, and LTBP1 being potential key inductive factors secreted by dermal papilla cells in the regeneration of hair follicles.

Long noncoding RNA expression in dermal papilla cells contributes to hairy gene regulation

Dermal papilla (DP) cells may be the source of dermal-derived signaling molecules involved in hair-follicle development and postnatal hair cycling. Early-passage DP cells can induce hair growth in vivo, but, on further culture, this ability is lost. The cellular mechanisms underlying the hair-follicle induction property of early-passage DP cells are unclear. Long noncoding RNAs (lncRNAs) are an important class of genes involved in various biological functions. They are aberrantly expressed and play roles in the regulation of the Wnt signaling pathway, a critical point in maintaining hair-induction activity. LncRNA microarray revealed 1683 upregulated and 1773 downregulated lncRNAs in passage-4 DP cells compare with passage-10 DP cells. To investigate the relation between lncRNAs and coding genes in WNT signaling, we constructed a coding-noncoding gene co-expression network using lncRNAs and coding genes that were differentially expressed between the passage-4 and -10 DP cells. RP11-766N7.3, H19 and HOTAIR are specific lncRNAs that were aberrantly expressed in DP cells and played an important role in regulating Wnt signaling. This study may provide potential targets for discovering the hair-follicle induction mechanism of early-passage DP cells.