Comparative Proteomic Analysis of Liver Tissues and Serum in db/db Mice.

BACKGROUND AND AIMS: Non-alcoholic fatty liver disease (NAFLD) affects one-quarter of individuals worldwide. Liver biopsy, as the current reliable method for NAFLD evaluation, causes low patient acceptance because of the nature of invasive sampling. Therefore, sensitive non-invasive serum biomarkers are urgently needed. RESULTS: The serum gene ontology (GO) classification and Kyoto encyclopedia of genes and genomes (KEGG) analysis revealed the DEPs enriched in pathways including JAK-STAT and FoxO. GO analysis indicated that serum DEPs were mainly involved in the cellular process, metabolic process, response to stimulus, and biological regulation. Hepatic proteomic KEGG analysis revealed the DEPs were mainly enriched in the PPAR signaling pathway, retinol metabolism, glycine, serine, and threonine metabolism, fatty acid elongation, biosynthesis of unsaturated fatty acids, glutathione metabolism, and steroid hormone biosynthesis. GO analysis revealed that DEPs predominantly participated in cellular, biological regulation, multicellular organismal, localization, signaling, multi-organism, and immune system processes. Protein-protein interaction (PPI) implied diverse clusters of the DEPs. Besides, the paralleled changes of the common upregulated and downregulated DEPs existed in both the liver and serum were validated in the mRNA expression of NRP1, MUP3, SERPINA1E, ALPL, and ALDOB as observed in our proteomic screening. METHODS: We conducted hepatic and serum proteomic analysis based on the leptin-receptor-deficient mouse (db/db), a well-established diabetic mouse model with overt obesity and NAFLD. The results show differentially expressed proteins (DEPs) in hepatic and serum proteomic analysis. A parallel reaction monitor (PRM) confirmed the authenticity of the selected DEPs. CONCLUSION: These results are supposed to offer sensitive non-invasive serum biomarkers for diabetes and NAFLD.

Transglutaminase 3 suppresses proliferation and cisplatin resistance of cervical cancer cells by inactivation of the PI3K/AKT pathway.

Recent studies have shown that dysregulation of transglutaminase 3 (TGM3) is related to the aggressive progression of several cancer types. Our study aimed to determine the function of TGM3 in cervical cancer (CC) tumorigenesis. Gene expression profiles GSE63514, GSE9750, GSE46857 and GSE67522 were obtained from the Gene Expression Omnibus (GEO) database. Overlapping differential expressed genes (DEGs) in CC were screened using GEO2R online tool and Venn diagram software. The Kaplan-Meier plotter was used to determine overall survival. TGM3 expression was analyzed based on GEO and The Cancer Genome Atlas (TCGA) databases, qRT-PCR and western blot analyses. Cell proliferation was evaluated by CCK-8 and EdU incorporation assays. The half-maximal inhibitory concentration (IC50) value of cisplatin and cell apoptosis was assessed by CCK-8 and TUNEL assays, respectively. P-glycoprotein (P-gp) expression and the changes of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway were examined using western blot analysis. We identified 3 overlapping DEGs, including TGM3, glutathione peroxidase 3 (GPX3), and alpha B-crystallin (CRYAB), which were downregulated in CC tissues. TGM3 expression was reduced in CC cells and related to the poor prognosis of CC patients. TGM3 overexpression retarded the proliferation, reduced IC50 value of cisplatin, accelerated cisplatin-induced apoptosis, and inhibited cisplatin-induced P-gp level in CC cells. Furthermore, TGM3 overexpression suppressed the PI3K/Akt pathway in CC cells. Moreover, treatment with 740Y-P, a PI3K activator, abolished the effect of TGM3 overexpression on proliferation and cisplatin resistance in CC cells. In conclusion, overexpression of TGM3 suppressed proliferation and cisplatin resistance in CC cells by blocking the PI3K/Akt pathway.

TRIM56 protects against nonalcoholic fatty liver disease by promoting the degradation of fatty acid synthase.

Nonalcoholic fatty liver disease (NAFLD) encompasses a disease continuum from simple steatosis to nonalcoholic steatohepatitis (NASH). However, there are currently no approved pharmacotherapies for NAFLD, although several drugs are in advanced stages of clinical development. Because of the complex pathophysiology and heterogeneity of NAFLD, the identification of potential therapeutic targets is clinically important. Here, we demonstrated that tripartite motif 56 (TRIM56) protein abundance was markedly downregulated in the livers of individuals with NAFLD and of mice fed a high-fat diet. Hepatocyte-specific ablation of TRIM56 exacerbated the progression of NAFLD, while hepatic TRIM56 overexpression suppressed it. Integrative analyses of interactome and transcriptome profiling revealed a pivotal role of TRIM56 in lipid metabolism and identified the lipogenesis factor fatty acid synthase (FASN) as a direct binding partner of TRIM56. TRIM56 directly interacted with FASN and triggered its K48-linked ubiquitination-dependent degradation. Finally, using artificial intelligence-based virtual screening, we discovered an orally bioavailable small-molecule inhibitor of FASN (named FASstatin) that potentiates TRIM56-mediated FASN ubiquitination. Therapeutic administration of FASstatin improved NAFLD and NASH pathologies in mice with an optimal safety, tolerability, and pharmacokinetics profile. Our findings provide proof of concept that targeting the TRIM56/FASN axis in hepatocytes may offer potential therapeutic avenues to treat NAFLD.

Growth differentiation factor 15 is dispensable for acetaminophen-induced liver injury in mice.

Acetaminophen (APAP)-induced liver injury (AILI) has been recognized as a pivotal contributor to drug-induced liver failure in Western countries, but its molecular mechanism remains poorly understood. Growth differentiation factor 15 (GDF15) is a pleiotropic factor that alleviates non-alcoholic liver steatohepatitis, liver fibrosis and liver injury. The aim of the present study was to examine the possibility whether GDF15 confers protection against AILI. We found that the gene expression of Gdf15 was increased significantly after APAP overdose in mice. Next, the role of Gdf15 in AILI was evaluated by hepatic Gdf15 overexpression (using adeno-associated virus serotype 8), injection with recombinant human GDF15 (rhGDF15) and Gdf15 knockout mice after challenge with APAP. A marked elevation of Gdf15 was observed after AILI. However, there were no significant differences in AILI-related liver injury and JNK phosphorylation after Gdf15 overexpression, rhGDF15 injection or Gdf15 deficiency. Together, we conclude that, despite a noticeable elevation of Gdf15 level after AILI, Gdf15 is dispensable for APAP-induced AILI. Our study further suggests that genomic analysis of mRNA expression after APAP overdose is of limited relevance unless followed up by a functional analysis of candidate genes in vivo.

Mouse models of nonalcoholic fatty liver disease (NAFLD): pathomechanisms and pharmacotherapies.

The prevalence of non-alcoholic fatty liver disease (NAFLD) increases year by year, and as a consequence, NAFLD has become one of the most prevalent liver diseases worldwide. Unfortunately, no pharmacotherapies for NAFLD have been approved by the United States Food and Drug Administration despite promising pre-clinical benefits; this situation highlights the urgent need to explore new therapeutic targets for NAFLD and for the discovery of effective therapeutic drugs. The mouse is one of the most commonly used models to study human disease and develop novel pharmacotherapies due to its small size, low-cost and ease in genetic engineering. Different mouse models are used to simulate various stages of NAFLD induced by dietary and/or genetic intervention. In this review, we summarize the newly described patho-mechanisms of NAFLD and review the preclinical mouse models of NAFLD (based on the method of induction) and appraises the use of these models in anti-NAFLD drug discovery. This article will provide a useful resource for researchers to select the appropriate model for research based on the research question being addressed.

Protective roles of salicylic acid in maintaining integrity and functions of photosynthetic photosystems for alfalfa (Medicago sativa L.) tolerance to aluminum toxicity.

Aluminum (Al) can be detrimental to plant growth in areas with Al contamination. The objective of this study was to determine whether salicylic acid (SA) can improve plant tolerance to Al stress by mitigating Al toxicity for chloroplasts and photosynthetic systems in alfalfa (Medicago sativa L.). Plants were treated with Al (100 µM) for 3 d in a hydroponic system. The content of Al increased in leaves treated with Al, resulting in damage and deformation of chloroplasts. In Al-damaged leaves, chloroplast envelopes and starch granules disappeared; the lamellae and stroma lamella were loosely arranged and indistinguishable, and the number of grana was reduced; a large number of small plastoglobules appeared. Foliar spraying of 15 µM SA reduced Al content in roots and leaves and alleviated Al damages in chloroplasts. With 15 µM SA treatments, the chloroplast shape returned to a flat ellipsoid, thylakoids were arranged closely and regularly, chloroplasts had intact starch granules, and small plastoglobules disappeared. SA-treated plants had significantly higher aboveground biomass than the untreated control exposed to Al stress. Photosynthetic index and gene expression analyses demonstrated that SA could alleviate adverse effects of Al toxicity by increasing light capture efficiency, promoting electron transport in the photosynthetic electron transport chain and thylakoid lumen deacidification, and promoting synthesis of aenosine triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADPH). SA played protective roles in maintaining integrity and functions of photosystems in photosynthesis for plant tolerance to Al stress.

[Comments on Nigel Wiseman's "A Practical Sictionary of Chinese Medicine"--on Wiseman' s literal translation].

Comments were made on the word-for-word literal translation method used by Mr. Nigel Wiseman in A Practical Dictionary of Chinese Medicine. He believes that only literal translation can reflect Chinese medical concepts accurately. The so-called "word-for-word" translation is actually "English-word-for-Chinese-character" translation. First, he made a list of Single Characters with English Equivalents, and then he replaced each character of Chinese medical terms with the assigned English equivalent. Many English terms thus produced are confusing. The defect of the word-for-word literal translation stems from the erroneous idea that the single character constitutes the basic element of meaning corresponding to the notion of "word" in English, and the meaning of a disyllabic or polysyllabic Chinese word is simply the addition of the meanings of the two or more characters. Another big mistake is the negligence of the polysemy of Chinese characters. One or two English equivalents can by no means cover all the various meanings of a polysemous character as a monosyllabic word. Various examples were cited from this dictionary to illustrate the mistakes.