In vitro acne disease model from inertial focusing effect for studying the interactions between sebocyte glands and macrophages.

Acne is one of the most widespread skin diseases. The acne mechanism is intricate, involving interactions between different types of cells (i.e., sebocytes and macrophages). One of the challenges in studying the mechanism of acne is that current in vitro culture methods cannot reflect the 3D cellular environment in the tissue, including inflammatory stimuli and cellular interactions especially the interactions between sebocytes and immune cells. To solve this issue, we generated an in vitro acne disease model consisting of 3D artificial sebocyte glands and macrophages through the inertial focusing effect method. Using this model, we produced a controllable inflammatory environment similar to the acne pathogenetic process in the skin. The 3D artificial sebocyte glands and macrophages can be separated for analyzing each cell type, assisting the in-depth understanding of the acne mechanism. This study indicates that proinflammatory macrophages promote lipid accumulation and induce oxidative stress in sebocyte glands. Additionally, in an inflammatory environment, sebocyte glands induce macrophage polarization into the M1 phenotype. Employing this model for drug screening, we also demonstrated that, cannabidiol (CBD), a clinically investigated drug, is effective in restoring lipid accumulation, oxidative stress, inflammatory cytokines and macrophage polarization in the acne disease.

3D artificial sebocyte glands from inertial focusing effect for facile and flexible analysis of light damage and drug screening.

The sebaceous gland is a neuro-immuno-endocrine organ responsible for maintaining regular skin functions. Overdose exposure of UV and visible light (e.g., blue light) can cause sebocyte gland function disorders or even different diseases (e.g., chronic actinic dermatitis). Studying the mechanism of light-induced damage in sebaceous glands has been challenging, since ex vivo culture of sebaceous glands is difficult due to its short life in culture medium. To address this issue, a versatile 3D artificial sebocyte gland model was established using the inertial focusing effect for studying the impact of light damage and screening potential drugs. The artificial sebocyte gland exhibited specific biological function and structure similar to natural sebocyte glands. Using this artificial sebocyte gland, the interactions between the artificial organ and blue light or UV were studied. The results indicated that UV and blue light upregulated lipid secretion and downregulated cell viability within the sebocytes. Light damage intensified oxidative stress and promoted pro-inflammation cytokines (i.e., IL-1ß and TNF-α) production in the artificial sebocytes. Additionally, the therapeutic effects of cannabidiol, a clinically tested drug for treating acne, was also indicated on restoring light damaged sebaceous gland functions. These results indicate that the 3D artificial sebocyte gland could be a versatile, fast, and low-cost platform for skincare studies or drug screening.

LINC00641/miR-582-5p mediate oxaliplatin resistance by activating autophagy in gastric adenocarcinoma.

The poor prognosis of gastric adenocarcinoma is partly due to chemotherapy failure, especially the oxaliplatin-based chemotherapy. However, the specific mechanism of oxaliplatin resistance is unclear. We aim to find the roles that LINC00641 and miR-582-5p play in regulating oxaliplatin resistance. Quantitative reverse transcriptase-PCR was used to evaluate the expression of LINC00641 and microRNA-582-5p (miR-582-5p) in gastric cancer both in vivo and in vitro. Transwell and CCK-8 assays were performed; and LC3 I/II and p62 were detected by western blot to evaluate the activation of autophagy. LINC00641 expression was associated with prognosis and oxaliplatin resistance in patients with gastric adenocarcinoma. The expression of LINC00641 was higher in gastric cancer tissues; whereas miR-582-5p was down-regulated in gastric cancer tissues. Moreover, LINC00641 was highly expressed in oxaliplatin-resistant cell lines and miR-582-5p was down-regulated. In addition, LINC00641 negatively regulated the expression of miR-582-5p. With regard to biological functions, down-regulation of LINC00641 suppressed cell migration and proliferation. Further experiments indicated that down-regulation of LINC00641 inhibited the autophagy process, making gastric cancer cells more sensitive to oxaliplatin. LINC00641 and miR-582-5p are biomarkers for predicting overall survival, as they were involved in regulating oxaliplatin resistance by altering autophagy in gastric adenocarcinoma.

Transthyretin Regulated by linc00657/miR-205-5p Promoted Cholesterol Metabolism by Inducing SREBP2-HMGCR and Inhibiting LXRα-CYP7A1.

BACKGROUND: Transthyretin functions as a serum transport protein for retinol. Transthyretin has been found associated with amyloid diseases and it is an important nutrition indicator. For this study, we aimed to investigate the up and down stream molecular mechanisms of Transthyretin in cholesterol metabolism. METHODS: We have recruited 237 fatty liver patients to evaluate the serum Transthyretin and its association with cholesterol and other clinical characteristics. And then Transthyretin was up and down regulated by plasmids to investigate its downstream mechanisms in vitro. RESULTS: Linc00657 (NORAD) and miR-205-5p were further confirmed as upstream mechanisms to regulate Transthyretin. High level Transthyretin patients tended to have higher cholesterol, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) level than low level Transthyretin patients. Moreover, Transthyretin expressed higher in LO2 than that in QSG7701. Furthermore, Transthyretin negatively regulated CYP7A1, LXRα and ABCG 5/8 and positively regulated HMGCR and SREBP2. Linc00657 expressed lower in LO2 than that in QSG7701 and miR-205-5p expressed higher in LO2 than that in QSG7701. Furthermore, we found that linc00657 negatively regulated miR-205-5p and Transthyretin in vitro. And, up regulation of miR-205-5p in linc00657-LO2 cell line could reverse the inhibitory effects of linc00657 on Transthyretin. CONCLUSION: Transthyretin regulated cholesterol metabolism mainly through inhibiting LXRα-CYP7A1 and promoting SREBP2-HMGCR. And linc00657 could negatively regulate Transthyretin by inhibiting miR-205-5p, providing novel therapeutic targets for decreasing serum cholesterol level. Besides, Transthyretin could be a potential novel biomarker for predicting liver function along with AST and ALT.