P38γ modulates the lipid metabolism in non-alcoholic fatty liver disease by regulating the JAK-STAT signaling pathway.

Non-alcoholic fatty liver disease (NAFLD) is a major health problem in Western countries and has become the most common cause of chronic liver disease. Although NAFLD is closely associated with obesity, inflammation, and insulin resistance, its pathogenesis remains unclear. The disease begins with excessive accumulation of triglycerides in the liver, which in turn leads to liver cell damage, steatosis, inflammation, and so on. P38γ is one of the four isoforms of P38 mitogen-activated protein kinases (P38 MAPKs) that contributes to inflammation in different diseases. In this research, we investigated the role of P38γ in NAFLD. In vivo, a NAFLD model was established by feeding C57BL/6J mice with a methionine- and choline-deficient (MCD) diet and adeno-associated virus (AAV9-shRNA-P38γ) was injected into C57BL/6J mice by tail vein for knockdown P38γ. The results indicated that the expression level of P38γ was upregulated in MCD-fed mice. Furthermore, the downregulation of P38γ significantly attenuated liver injury and lipid accumulation in mice. In vitro, mouse hepatocytes AML-12 were treated with free fatty acid (FFA). We found that P38γ was obviously increased in FFA-treated AML-12 cells, whereas knockdown of P38γ significantly suppressed lipid accumulation in FFA-treated AML-12 cells. Furthermore, P38γ regulated the Janus Kinase-Signal transducers and activators of transcription (JAK-STAT) signaling pathway. Inhibition of P38γ can inhibit the JAK-STAT signaling pathway, thereby inhibiting lipid accumulation in FFA-treated AML-12 cells. In conclusion, our results suggest that targeting P38γ contributes to the suppression of lipid accumulation in fatty liver disease.

Natural products, extracts and formulations comprehensive therapy for the improvement of motor function in alcoholic liver disease.

Alcoholic liver disease (ALD) is a major cause of chronic liver disease worldwide that afflicts human health. With the in-depth study of the disease, its pathogenesis has gradually become clear. Although great breakthroughs have been made in the research of ALD, the research and development of drugs related to ALD has lagged behind seriously. However, natural products have always inspired the development of drugs. Meanwhile, there is evidence that some natural products can also play a certain role in the treatment of ALD. Thus, we reviewed the natural products, extracts and formulations with potential anti-ALD activities by consulting the relevant data in the databases of PubMed, Web of Science and CNKI databases, in order to elucidate the regulated mechanism of these natural products. Sum up, the insights provided in present review will be needed for further exploration of botanical drugs in the development of ALD therapy.

New advances of TMEM88 in cancer initiation and progression, with special emphasis on Wnt signaling pathway.

Transmembrane protein 88 (TMEM88), a newly discovered protein localized on the cell membrane. Recent studies showed that TMEM88 was involved in the regulation of several types of cancer. TMEM88 was expressed at significantly higher levels in breast cancer (BC) cell line than in normal breast cell line with co-localized with Dishevelled (DVL) in the cytoplasm of BC cell line. TMEM88 silencing in the ovarian cancer cell line CP70 resulted in significant upregulation of Wnt downstream genes (c-Myc, cyclin-D1) and other Wnt target genes including JUN, PTIX2, CTNNB1 (ß-catenin), further supporting that TMEM88 inhibits canonical Wnt signaling pathway. Wnt signaling pathway has been known to play important roles in many diseases, especially in cancer. For instance, hepatocellular carcinoma (HCC) has become one of the most common tumors harboring mutations in the Wnt signaling pathway. As the inhibitor of Wnt signaling, TMEM88 has been considered to act as an oncogene or a tumor suppressor. Up-regulated TMEM88 or gene therapy approaches could be an effective therapeutic approach against tumor as TMEM88 inhibits Wnt signaling through direct interaction with DVL. Here, we review the current knowledge on the functional role and potential clinical application of TMEM88 in the control of various cancers. Highlights Wnt signaling displays an important role in several pathogenesis of cancer. Wnt signaling pathway is activated during cancer development. TMEM88 has an impact on cancer by inhibiting canonical Wnt signaling. We discuss the importance and new applications of TMEM88 in cancer therapy.

TMEM88 mediates inflammatory cytokines secretion by regulating JNK/P38 and canonical Wnt/ß-catenin signaling pathway in LX-2 cells.

Recent data have shown that Transmembrane protein 88 (TMEM88), a newly discovered protein localized on the cell membrane, interacts with the PDZ domain of disheveled-1 (Dvl-1) in Xenopus embryos. Indeed, TMEM88 might inhibit the canonical Wnt/ß-catenin signaling pathway by competing with LRP5/6 for interaction with Dvl-1. TMEM88 plays a crucial role in regulating human stem cell differentiation and embryonic development. Until recently, the function of TMEM88 has been a matter of debate. In this study, we explore the role of TMEM88 in cytokine secretion and the role of the MAPK and Wnt/ß-catenin signaling pathway in tumor necrosis factor-alpha (TNF-α)-induced TMEM88 expression in LX-2 cells. We demonstrated that overexpression of TMEM88 results in an upregulation of IL-6 and IL-1ß secretion. On the other hand, knockdown of TMEM88 by transfecting siRNA decreased IL-6 and IL-1ß secretion in LX-2 cells. Meanwhile, the results showed that TMEM88 silencing could increase the expression levels of canonical Wnt/ß-catenin accompanied with upregulated phosphorylation of wnt3a, wnt10b and ß-catenin protein levels in response to TNF-α. In conclusion, these results indicated that TMEM88 plays a significant role in TNF-α-enhanced cytokine (IL-6 and IL-1ß) secretion of LX-2 cells via regulating JNK/P38 and canonical Wnt/ß-catenin signaling pathway.

NUP85 alleviates lipid metabolism and inflammation by regulating PI3K/AKT signaling pathway in nonalcoholic fatty liver disease.

Nonalcoholic fatty liver disease (NAFLD) is one of the common causes of chronic liver disease in the world. The problem of NAFLD had become increasingly prominent. However, its pathogenesis is still indistinct. As we all know, NAFLD begins with the accumulation of triglyceride (TG), leading to fatty degeneration, inflammation and other liver tissues damage. Notably, structure of nucleoporin 85 (NUP85) is related to lipid metabolism and inflammation of liver diseases. In this study, the results of researches indicated that NUP85 played a critical role in NAFLD. Firstly, the expression level of NUP85 in methionine-choline-deficient (MCD)-induced mice increased distinctly, as well as the levels of fat disorder and inflammation. On the contrary, knockdown of NUP85 had the opposite effects. In vitro, AML-12 cells were stimulated with 2 mm free fatty acids (FFA) for 24 h. Results also proved that NUP85 significantly increased in model group, and increased lipid accumulation and inflammation level. Besides, NUP85 protein could interact with C-C motif chemokine receptor 2 (CCR2). Furthermore, when NUP85 protein expressed at an extremely low level, the expression level of CCR2 protein also decreased, accompanied with an inhibition of phosphorylation of phosphoinositol-3 kinase (PI3K)-protein kinase B (AKT) signaling pathway. What is more, trans isomer (ISRIB), a targeted inhibitor of NUP85, could alleviate NAFLD. In summary, our findings suggested that NUP85 functions as an important regulator in NAFLD through modulation of CCR2.

The Therapeutic Effect of Traditional Chinese Medicine on Inflammatory Diseases Caused by Virus, Especially on Those Caused by COVID-19.

Inflammasomes are large multimolecular complexes best recognized because of their ability to control activation of caspase-1, which in turn regulates the maturation of interleukin-18 (IL-18) and interleukin-1 ß (IL-1ß). IL-1ß was originally identified as a pro-inflammatory cytokine, capable of inducing local and systemic inflammation as well as a fever response reaction in response to infection or injury. Excessive production of IL-1ß is related to inflammatory and autoimmune diseases. Both coronavirus disease 2019 (COVID-19) and severe acute respiratory syndrome (SARS) are characterized by excessive inflammatory response. For SARS, there is no correlation between viral load and worsening symptoms. However, there is no specific medicine which is available to treat the disease. As an important part of medical practice, TCM showed an obvious therapeutic effect in SARS-CoV-infected patients. In this article, we summarize the current applications of TCM in the treatment of COVID-19 patients. Herein, we also offer an insight into the underlying mechanisms of the therapeutic effects of TCM, as well as introduce new naturally occurring compounds with anti-coronavirus activity, in order to provide a new and potential drug development strategy for the treatment of COVID-19.

TMEM100 mediates inflammatory cytokines secretion in hepatic stellate cells and its mechanism research.

Recent studies have shown that Transmembrane protein 100 (TMEM100) is a gene at locus 17q32 encoding a 134-amino acid protein with two hypothetical transmembrane domainsa, and first identified as a transcript from the mouse genome. As a downstream target gene of bone morphogenetic protein (BMP)-activin receptor-like kinase 1 (ALK1) signaling, it was activated to participate in inducing arterial endothelium differentiation, maintaining vascular integrity, promoting cell apoptosis, inhibiting metastasis and proliferation of cancer cells. However, evidence for the function of TMEM100 in inflammation is still limited. In this study, we explore the role of TMEM100 in inflammatory cytokine secretion and the role of MAPK signaling pathways in tumor necrosis factor-alpha (TNF-α)-induced TMEM100 expression in LX-2 cells. We found that the expression of TMEM100 was decreased markedly in human liver fibrosis tissues, and its expression was also inhibited in LX-2 cells induced by TNF-α, suggesting that it might be associated with the development of inflammation. Therefore, we demonstrated that overexpression of TMEM100 by transfecting pEGFP-C2-TMEM100 could lead to the down-regulation of IL-1ß and IL-6 secretion. Moreover, we found that expression changes of TMEM100 could be involved in inhibition or activation of MAPK signaling pathways accompanied with regulating phosphorylation levels of ERK and JNK protein in response to TNF-α. These results suggested that TMEM100 might play an important role in the secretion of inflammatory cytokines (IL-1ß and IL-6) of LX-2 cells induced by TNF-α, and MAPK (ERK and JNK) signaling pathways might participate in its induction of expression.