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Adipose tissue inflammation is now considered to be a key process underlying metabolic diseases in obese individuals. However, it remains unclear how adipose inflammation is initiated and maintained or the mechanism by which inflammation develops. We found that microRNA-802 (Mir802) expression in adipose tissue is progressively increased with the development of dietary obesity in obese mice and humans. The increasing trend of Mir802 preceded the accumulation of macrophages. Adipose tissue-specific knockout of Mir802 lowered macrophage infiltration and ameliorated systemic insulin resistance. Conversely, the specific overexpression of Mir802 in adipose tissue aggravated adipose inflammation in mice fed a high-fat diet. Mechanistically, Mir802 activates noncanonical and canonical NF-κB pathways by targeting its negative regulator, TRAF3. Next, NF-κB orchestrated the expression of chemokines and SREBP1, leading to strong recruitment and M1-like polarization of macrophages. Our findings indicate that Mir802 endows adipose tissue with the ability to recruit and polarize macrophages, which underscores Mir802 as an innovative and attractive candidate for miRNA-based immune therapy for adipose inflammation.

Abstract Hepatocellular carcinoma (HCC) is associated with a poor prognosis. Our previous study demonstrated that Pleomorphic adenoma gene like-2 (PLAGL2) was a potential therapeutic target in HCC. However, the mechanisms that lead to the upregulation of PLAGL2 in HCC remain unclear. The present study revealed that stress-induced epinephrine increased the expression of PLAGL2, thereby promoting the progression of HCC. Furthermore, PLAGL2 knockdown inhibited epinephrine-induced HCC development. Mechanistically, epinephrine upregulated ubiquitin-specific protease 10 (USP10) to stabilize PLAGL2 via the adrenergic β-receptor-2-c-Myc (ADRB2-c-Myc) axis. Furthermore, PLAGL2 acted as a transcriptional regulator of USP10, forming a signaling loop. Taken together, these results reveal that stress-induced epinephrine activates the PLAGL2-USP10 signaling loop to enhance HCC progression. Furthermore, PLAGL2 plays a crucial role in psychological stress-mediated promotion of HCC progression.

Background/Aims: Abnormal glucose metabolism and lipid metabolism are two key issues in Type 1 diabetes mellitus (T1DM). Insulin can control carbohydrate metabolism adequately, but cannot regulate lipid metabolism well in patients with T1DM. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have cured type 2 diabetes mellitus in clinical trials and have improved T1DM glycemic control in preclinical studies. However, previous studies have not reported whether GLP-1 can lower the serum concentration of non-esterified fatty acids (NEFAs). In this study, we examine whether GLP-1 can affect serum NEFA levels. Methods: The bioactivity of EGLP-1 (a novel GLP-1 analog) in vitro was analyzed in CG-HEK293 cells and with high-performance liquid chromatography. An intraperitoneal glucose tolerance test (IPGTT) was used to analyze the acute and sustained hypoglycemic effects of EGLP-1 in normal C57BL/6J mice. Streptozotocin-induced hyperglycemic mice were used to study the effects of EGLP-1 on blood glucose and NEFAs as well as its mechanism. Results: EGLP-1 activated GLP-1R and resisted dipeptidyl peptidase-IV digestion in vitro. Additionally, EGLP-1 had an insulinotropic action in vivo that lasted for approximately 6 h. In Streptozotocin-induced hyperglycemic mice, EGLP-1 improved hyperglycemia, inhibited food intake, and increased β-cell area. Serum physiological indexes showed that insulin and C-peptide levels were increased, while NEFA and triacylglycerol concentrations were decreased. Western blot analysis revealed that EGLP-1 significantly reduced phosphorylated-hormone sensitive lipase (pHSL) levels in white adipose tissue. Conclusions: EGLP-1 can improve hyperglycemia by increasing islet β-cell area and improving β-cell function, possibly due to reduced NEFA content in serum by lowering pHSL levels.

Background/Aims: Pancreatic cancer remains one of the deadliest human malignancies, the lethality of which may be attributed to the presence of pancreatic cancer stem cells (PCSCs), a small subpopulation of cells existing within pancreatic tumor with high carcinogenesis. Therefore, it is crucial to establish an efficient enrichment and culture system of PCSCs and identify the key genes involved in the regulation of PCSCs. The three-dimensional (3D) liquid suspension mammosphere culture system has been established for enrichment and culture of PCSCs in vitro as the cell spheres are likely to originate from individual cell clone, but it has been challenged because the cell spheroids could be a result of cell aggregation. Methods: We optimized the existing culture system by adding methylcellulose to create a 3D semi-solid system which prevented the non-specific aggregation. Then we identified the CSC properties of Panc-1 spheroid cells cultured by this system by detecting the genes associated with stemness and by evaluation of the tumorigenicity in vitro and in vivo through invasion, migration and xenograft experiments methods. Subsequently, we performed high-throughput sequencing (HTS) of the Panc-1 spheroid cells. Results: We confirmed the PCSCs properties and high malignancy of the Panc-1 spheroid cells enriched by our novel 3D semi-solid system both in vitro and in vivo. Hundreds of mRNA, microRNA (miRNA) and dozens of long non-coding RNA (LncRNA) were identified to be differentially regulated in PCSCs-like Panc-1 spheroid cells compared with their parental cells by HTS. Conclusions: Our results demonstrate an efficient enrichment and culture system for Panc-1 spheroid cells with the PCSCs properties. The differentially expressed genes and their targets identified by the HTS of the Panc-1 spheroid cells can serve as new potential biomarkers for pancreatic cancer diagnosis and targeted therapy.

Abstract Background Mycoplasma hyopneumoniae (Mhp) causes porcine enzootic pneumonia, a disease that cause major economic losses in the pig industry. Dendritic cells (DCs), the most effective antigen-presenting cells, are widely distributed beneath respiratory epithelium, DCs uptake and present antigens to T cells, to initiate protective immune responses in different infections. In this study, we investigated the role of porcine DCs in vaccine Mhp-168 exposure. Results The antigen presenting ability of DCs were improved by vaccine Mhp-168 exposure. DCs could activate T-cell proliferation by up-regulating the antigen presenting molecule MHCII expression and co-stimulatory molecule CD80/86. However, the up-regulation of IL-10 and accompany with down-regulation of IFN-γ gene level may account for the limitation of attenuated Mhp-168 strain use as vaccine alone. Conclusion These findings are benefit for exploring the protection mechanisms and the possible limitations of this attenuated Mhp-168 vaccine.

Sanhuang Xiexin Tang (SXT), a classic prescription, has been clinically used to cure diabetes for thousands of years, but its mechanism remains unclear. Here, a systematic in-depth research was performed to unravel how it worked by the signaling pathway and metabonomics analysis. Our studies were conducted using high-fat diets (HFD) and streptozocin (STZ)-induced type 2 diabetes mellitus (T2DM) rats. The blood glucose was measured by a glucose-meter. Protein contents were determined by western blotting or ELISA and mRNA expression was identified by RT-PCR analysis. The pathological status of pancreas was assessed by histopathological analysis. Furthermore, Ultra Performance Liquid Chromatography-Quadrupole-Time of Flight/Mass Spectrometry (UPLC-Q-TOF/MS) coupled with multivariate statistical analysis was performed to discover potential biomarkers and the associated pathways. Hyperglycaemia, insulin resistance, dyslipidemia and inflammation in T2DM rats were significantly ameliorated after 7-week oral administration of SXT. The expressions of phosphatidylinositol-3-kinase (PI-3K), protein kinase B (Akt), glucose transporters-4 (GLUT4) Mrna, and p-PI-3K, p-Akt, GLUT4 protein involved in the PI-3K/Akt signaling pathway of T2DM were markedly up-regulated. Further investigation indicated that the perturbance of metabolic profiling in T2DM rats was obviously reversed by SXT and 38 potential biomarkers were screened and identified. Our study might help clarify the mechanism of SXT and provide some evidences for its clinical application in the future.

Abstract Salt crystallization is one of the most important factors causing weathering in grottoes. Cumulative crystallization of salts causes damage such as flaking and peeling of the rocks and accelerates the weathering processes of the grottoes. The accumulated crystalline salts cause spalling, skinning and other damage and accelerate the weathering process of the grotto rock body. It is necessary to study the existing glutenite rock grottoes. This paper took the glutenite rock of the Maijishan Grottoes as a case study, and Na2SO4 or MgSO4 solutions were applied to glutenite rock specimens subjected to different deterioration cycles. The crystallization patterns of the two different salts and their damage to the glutenite rock were analyzed and studied, the mechanism for salt crystallization damage to the glutenite rock was explored, and the crystallization pressures of the two salts in the glutenite rock were derived with theoretical calculations. The results showed that both Na2SO4 and MgSO4 crystallization damaged the glutenite rock, and the former different sulfate solutions changed at different rates, and the changes in the wave caused faster damage than the latter. The physical indices of the rock samples in the velocities and tensile strengths were consistent. Na2SO4 was mainly accumulated on the surface of the specimen and damaged the glutenite rock centripetally via pulverization and exfoliation. MgSO4 mainly crystallized inside the glutenite rock, which created internal fissures and reduced the strength of the rock. The theoretical maximum crystallization pressures of Na2SO4 and MgSO4 in the glutenite rock specimens reached 33.00 MPa and 9.94 MPa, respectively. This study provides a theoretical basis for studies of salt crystallization in glutenite rock grottoes and provides a method for protecting the stones in cultural heritage sites against weathering.

Abstract Collective detachment of cancer cells at the invading front could generate efficient metastatic spread. However, how cancer cell clusters shed from the leading front remains unknown. We previously reported that the dynamic expression of CD44 in breast cancers (BrCas) at collectively invading edges was associated with tumor-associated macrophages (TAMs). In this study, we first observed that the highly expressed CD44 (CD44high) cancer cell clusters were located in the BrCa circulating vessels, accompanied by CD206+ TAMs. Next, we identified that the cancer cell clusters can be converted to an invasive CD44high state which was induced by TAMs, thus giving rise to CD44-associated signaling mediated cohesive detachment. Then, we showed that disrupting CD44-signaling inhibited the TAMs triggered cohesive detaching using 3D organotypic culture and mouse models. Furthermore, our mechanistic study showed that the acquisition of CD44high state was mediated by the MDM2/p53 pathway activation which was induced by CCL8 released from TAMs. Blocking of CCL8 could inhibit the signaling cascade which decreased the CD44-mediated cohesive detachment and spread. Our findings uncover a novel mechanism underlying collective metastasis in BrCas that may be helpful to seek for potential targets.

A major source of β cell generation is pancreatic progenitor-like cell differentiation. Multiple studies have confirmed that stem cell metabolism plays important roles in self-renewal and proliferation. In the absence of glucose, glutamine provides the energy for cell division and growth. Furthermore, α-ketoglutarate (αKG), a precursor for glutamine synthesis, is sufficient for enabling glutamine-independent cell proliferation. We have demonstrated that αKG contributes to the large-scale proliferation of pancreatic progenitor-like cells that can provide an ample amount of clinically relevant β cells. We compared the mRNA expression of a subset of genes, the abundance of ATP, reactive oxide species, mitochondrial number, and the colony-forming frequency between mouse pancreatic CD133+ and CD133- cells. We employed Real-Time PCR, immunostaining and passage assays to investigate self-renewal and proliferation of pancreatic progenitor-like cells in a 3D culture system in the presence and absence of αKG. The energy metabolism of CD133+ cells was more prone to oxidative phosphorylation. However, in the 3D culture system, when αKG was supplemented to the culture medium, the proliferation of the pancreatic progenitor-like cells was significantly elevated. We confirmed that the presence of αKG correlated with the up-regulation of Ten-Eleven Translocation (Tet). αKG can promote the proliferation of pancreatic progenitor-like cells via the up-regulation of Tet. [ABSTRACT FROM AUTHOR]