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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.

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 which 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.

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.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.We conducted hepatic and serum proteomic analysis based on the leptin-receptor-deficient mouse (These results are supposed to offer sensitive non-invasive serum biomarkers for diabetes and NAFLD.

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. After data mining using the Gene Expression Omnibus (GEO) database, we found that the gene expression of growth differentiation factor 15 (GDF15) increased significantly after APAP-induced hepatotoxicity in mouse liver. However, the precise role of GDF15 in AILI has yet to be clarified. To deal with this question, we first examined the temporal gene expression pattern of GDF15 after APAP treatment. Next, overexpression of hepatic GDF15 using adeno-associated virus serotype 8 (AAV8) was employed to investigate the role of GDF15 in AILI. In addition, therapeutic administration of recombinant human GDF15 (rhGDF15) was conducted to probe its curative effect after APAP overdose. We observed that protein expression of GDF15 was significantly increased after APAP overdose. However, there were no significant differences in AILI-related outcomes after overexpression or supplementation of GDF15. The contents of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST), morphological feature of liver, the level of reduced form of glutathione (GSH), the activation of c-Jun-N-terminal kinase (JNK), the expression of genes relevant to oxidative stress and cell proliferation were not remarkably changed between AAV8-GFP and AAV8-Gdf15 groups. Although the liver injury was not improved by rhGDF15 administration, the gene expression levels of glutamate-cysteine ligase modifier subunit (Gclm) and glutamate-cysteine ligase catalytic subunit (Gclc) which function downstream of Nrf2 signaling pathway were significantly increased. Altogether, despite a noticeable elevated expression after APAP overdose, GDF15 overexpression or supplementation exerted no significant ameliorative effect on AILI. Further mechanism and consequence of Gclm and Gclc elevation by GDF15 remains to be elucidated.

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.

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.

Objective: Pain from herniated disc is a common type of neuropathic pain. This study investigated whether electroacupuncture (EA) stimulation at distal–proximal combinations of acupoints in the rat model of neuropathic pain modulates spinal interleukin-1 beta (IL-1β) to induce acupuncture analgesia and possibly serve as a pain-relief modality for herniated disc. Methods: A rat model of neuropathic pain was established. Rats were randomly divided into normal, model, sham, EA 1, EA 2, and EA 3 groups. EA 1 rats were needled at bilateral Ex-B2, BL25, BL40, and BL60 acupoints. EA 2 rats were needled at bilateral BL40 and BL60. EA 3 rats were needled at bilateral L5 Ex-B2 and BL25. EA stimulation was administered once daily over 7 days. Mechanical withdrawal threshold from noxious mechanical stimulation was measured 1 day preoperatively and at 3, 5, and 7 days postoperatively. After 7 days of intervention, enzyme-linked immunosorbent assay (ELISA) was used to quantify IL-1β in the spinal cord. Results: Mechanical withdrawal threshold of rats in the model group decreased at 3 days postoperatively when compared with the normal group (P

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.