Temozolomide (TMZ), an alkylating agent, is recommended as the initial treatment for high-grade glioblastoma. TMZ is widely used, but its short half-life and the frequency of tumor resistance limit its therapeutic efficacy. In the present study, the anticancer effect of vitamin D (VD) combined with TMZ upon glioblastoma was determined, and the underlying mechanism of this effect was identified. Through cell viability, clonogenic and wound healing assays, the current study demonstrated that treatment of a C6 glioblastoma cell line with TMZ and VD resulted in significantly increased in vitro antitumor effects compared with either VD or TMZ alone. Autophagy, hypothesized to be the dominant mechanism underlying TMZ-based tumor cell death, was maximally activated in TMZ and VD co-treated C6 cells. This was demonstrated by ultrastructural observations of autophagosomes, increased size and number of microtubule-associated protein 1 light chain 3 (LC3) puncta and increased conversion of LC3-I to LC3-II. However, the extent of apoptosis was not significantly different between cells treated with TMZ and VD and those treated with TMZ alone. Addition of the autophagy inhibitor 3-methyladenine markedly inhibited the anticancer effect of TMZ and VD treatment, indicating that the chemosensitizing effect of VD in TMZ-based glioblastoma therapy is generated through enhancement of cytotoxic autophagy. TMZ and VD co-treatment also significantly inhibited tumor progression and prolonged survival duration in rat glioblastoma orthotopic xenograft models when compared with TMZ treatment alone. These in vivo results are concordant with the aforementioned in vitro results, together revealing that the combined use of TMZ and VD exerts synergistic antitumor effects on rat models of glioblastoma and may represent an effective therapeutic strategy.

Pax6, a paired homeobox DNA binding protein, has been found to be expressed in the cerebellum in both granule cells and their precursors in the external granular layer (EGL). In this study we have traced Pax6 expression through embryonic development in mice by using a polyclonal antibody against Pax6 and used it to study the cellular dispersal pattern of the EGL. During dispersal the EGL was thicker and Pax6 expression was more intense on the rostral side of the lateral corners of the cerebellum. Pax6 immunoreactive cells were found to be migrating from the EGL during the early stage of EGL dispersal, which suggested the early inward migration of granule cells. Double staining with various markers confirmed that the early-migrating cells are not Purkinje cells, interneurons or glia. Although the Pax6 immunoreactive cells within the cerebellum were not apparently proliferating, NeuN, a marker for postmitotic granule cells, was not expressed in these cells until E16. Furthermore, granule cells were observed migrating inwards from the EGL both during and after EGL dispersal. These early migrating granule cells populated the whole cerebellum. These findings offer novel views on specific stages of granule cell dispersal and migration.

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Atopic dermatitis (AD) is characterized by relapsing pruritus and skin dryness. Due to the pathogenic multiplicity and the adverse effects associated with the current therapeutics, development of transdermal drug delivery system is becoming an area of interest. Here, a novel topical film prepared with Rhus verniciflua extract (RVE)‐loaded pullulan hydrogel (RVE@PH) was synthesized and tested its therapeutic efficacy on the AD rats modeled by neonatal capsaicin injection method. The RVE@PH was characterized by a Fourier‐transform infrared spectroscopy and an in vitro release assay. Rat pups were randomly divided into two groups: vehicle‐treated (VEH; n = 5) and capsaicin‐treated (n = 15). The latter were given capsaicin subcutaneously at 24 h after birth for AD induction and further divided into three groups (n = 5 per each): not treated (CAP), pullulan hydrogel‐applied (PH), and RVE@PH‐applied (RVE‐PH). The pullulan hydrogel and RVE@PH were topically applied on shoulder lesions for 14 days (from 42 to 56 days after birth). Their phenotypes were compared based on the dermatitis score, epidermal thickness, mast cell infiltration, and serum myeloperoxidase (MPO) activities. The PH group showed significant attenuation in all the aforementioned values compared to the CAP group, suggesting that pullulan hydrogel itself has therapeutic activity against AD. Notably, the attenuations were more potent in the RVE‐PH group than the PH group, indicating that the therapeutic efficacy against AD is augmented by the presence of RVE, a loaded pharmaceutic. Collectively, these results indicate that RVE@PH inhibits AD through exerting the dual roles, that is, the pullulan hydrogel‐mediated physical and RVE‐mediated pharmaceutical actions. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 2325–2334, 2019.

Cholestatic liver cirrhosis (CLC) eventually proceeds to end-stage liver failure by mediating overwhelming deposition of collagen, which is produced by activated interstitial myofibroblasts. Although the beneficial effects of Rhus verniciflua Stokes (RVS) on various diseases are well-known, its therapeutic effect and possible underlying mechanism on interstitial fibrosis associated with CLC are not elucidated. This study was designed to assess the protective effects of RVS and its possible underlying mechanisms in rat models of CLC established by bile duct ligation (BDL). We demonstrated that BDL markedly elevated the serological parameters such as aspartate aminotransferase, alanine transaminase, total bilirubin, and direct bilirubin, all of which were significantly attenuated by the daily uptake of RVS (2 mg/kg/day) for 28 days (14 days before and after operation) via intragastric route. We observed that BDL drastically induced the deterioration of liver histoarchitecture and excessive deposition of extracellular matrix (ECM), both of which were significantly attenuated by RVS. In addition, we revealed that RVS inhibited BDL-induced proliferation and activation of interstitial myofibroblasts, a highly suggestive cell type for ECM production, as shown by immunohistochemical and semi-quantitative detection of α-smooth muscle actin and vimentin. Finally, we demonstrated that the anti-fibrotic effect of RVS was associated with the inactivation of Smad3, the key downstream target of a major fibrogenic cytokine, i.e., transforming growth factor β (TGF-β). Simultaneously, we also found that RVS reciprocally increased the expression of Smad7, a negative regulatory protein of the TGF-β/Smad3 pathway. Taken together, these results suggested that RVS has a therapeutic effect on CLC, and these effects are, at least partly, due to the inhibition of liver fibrosis by the downregulation of Smad3 and upregulation of Smad7.