Multispecies transcriptomics identifies SIKE as a MAPK repressor that prevents NASH progression.

Nonalcoholic fatty liver (NAFL) remains relatively benign, but high-risk to end-stage liver diseases become highly prevalent when it progresses into nonalcoholic steatohepatitis (NASH). Our current understanding of the development of NAFL to NASH remains insufficient. In this study, we revealed MAP kinase (MAPK) activation as the most notable molecular signature associated with NASH progression across multiple species. Furthermore, we identified suppressor of IKKε (SIKE) as a conserved and potent negative controller of MAPK activation. Hepatocyte-specific overexpression of Sike prevented NASH progression in diet- and toxin-induced mouse NASH models. Mechanistically, SIKE directly interacted with TGF-ß-activated kinase 1 (TAK1) and TAK1-binding protein 2 (TAB2) to interrupt their binding and subsequent TAK1-MAPK signaling activation. We found that indobufen markedly up-regulated SIKE expression and effectively improved NASH features in mice and macaques. These findings identify SIKE as a MAPK suppressor that prevents NASH progression and provide proof-of-concept evidence for targeting the SIKE-TAK1 axis as a potential NASH therapy.

Network-based analysis identifies key regulatory transcription factors involved in skin aging.

Skin aging is a complex process involving intricate genetic and environmental factors. In this study, we performed a comprehensive analysis of the transcriptional regulatory landscape of skin aging in canines. Weighted Gene Co-expression Network Analysis (WGCNA) was employed to identify aging-related gene modules. We subsequently validated the expression changes of these module genes in single-cell RNA sequencing (scRNA-seq) data of human aging skin. Notably, basal cell (BC), spinous cell (SC), mitotic cell (MC), and fibroblast (FB) were identified as the cell types with the most significant gene expression changes during aging. By integrating GENIE3 and RcisTarget, we constructed gene regulation networks (GRNs) for aging-related modules and identified core transcription factors (TFs) by intersecting significantly enriched TFs within the GRNs with hub TFs from WGCNA analysis, revealing key regulators of skin aging. Furthermore, we demonstrated the conserved role of CTCF and RAD21 in skin aging using an H2O2-stimulated cell aging model in HaCaT cells. Our findings provide new insights into the transcriptional regulatory landscape of skin aging and unveil potential targets for future intervention strategies against age-related skin disorders in both canines and humans.

The landscape of photoaging: From bench to bedside in a bibliometric analysis.

Background: Bibliometric software exists as a platform providing multiple algorithms to process the data to suffice diverse goals. Interpretation of the result must be based on insight into the meaning of the original data and the algorithm used. Medical Subject Headings (MeSH) terms represent the macro-level meaning of topics, keywords that commonly reflect the micro-level aspects. Objective: This study attempts to investigate the landscape of photoaging in the recent two decades by using bibliometric analysis. Methods: Published studies of photoaging were obtained from PubMed and Web of Science Core Collection (WoSCC) from 2000 to 2020. Basic bibliometric information was generated by WoSCC. Major MeSH terms were performed in cluster analysis and displayed as a hierarchical form to induce knowledge structure, detection algorithm on keywords was presented as a timeline form to obtain hotspots, and institutional clusters were labeled with keywords to achieve institutional characteristics. Results: A total of 2,727 and 2,705 studies were identified in PubMed and WoSCC, respectively. The number of photoaging-related studies at 3-year intervals grew steadily. The studies were performed in about 80 countries/regions. The highly frequent major MeSH terms were distributed in seven clusters, reflecting the etiology, pathophysiology, treatment, and prevention of photoaging. The hotspots changed as time went on, and the hotspots in recent 5 years were mitogen-activated protein kinase (MAPK), nuclear factor erythroid-derived 2-like 2 (Nrf2), and antioxidant activity. The highly productive institutions labeling in the top four clusters were Seoul National University, University of Michigan, China Medical University, and Harvard University, with corresponding keywords of UVB, retinoic acid, Nrf2, and rejuvenation. Conclusions: This study built a knowledge structure of pathophysiology, treatment and prevention of photoaging, and identified recent hotspots of MAPK, Nrf2, and antioxidant activity. We provide a landscape of photoaging, from the bench (pathophysiology) to bedside (treatment, prevention), and pave the way for future research.

A small molecule targeting ALOX12-ACC1 ameliorates nonalcoholic steatohepatitis in mice and macaques.

Nonalcoholic steatohepatitis (NASH) is a progressive liver disease and has become a leading indication for liver transplantation in the United States. The development of effective therapies for NASH is a major unmet need. Here, we identified a small molecule, IMA-1, that can treat NASH by interrupting the arachidonate 12-lipoxygenase (ALOX12)­acetyl-CoA carboxylase 1 (ACC1) interaction. IMA-1 markedly blocked diet-induced NASH progression in both male mice and Cynomolgus macaque therapeutic models. The anti-NASH efficacy of IMA-1 was comparable to ACC inhibitor in both species. Protein docking simulations and following functional experiments suggested that the anti-NASH effects of IMA-1 were largely dependent on its direct binding to a pocket in ALOX12 proximal to its ACC1-interacting surface instead of inhibiting ALOX12 lipoxygenase activity. IMA-1 treatment did not elicit hyperlipidemia, a known side effect of direct inhibition of ACC enzymatic activity, in both mice and macaques. These findings provide proof of concept across multiple species for the use of small molecule­based therapies for NASH.

Pharmacological inhibition of arachidonate 12-lipoxygenase ameliorates myocardial ischemia-reperfusion injury in multiple species.

Myocardial ischemia-reperfusion (MIR) injury is a major cause of adverse outcomes of revascularization after myocardial infarction. To identify the fundamental regulator of reperfusion injury, we performed metabolomics profiling in plasma of individuals before and after revascularization and identified a marked accumulation of arachidonate 12-lipoxygenase (ALOX12)-dependent 12-HETE following revascularization. The potent induction of 12-HETE proceeded by reperfusion was conserved in post-MIR in mice, pigs, and monkeys. While genetic inhibition of Alox12 protected mouse hearts from reperfusion injury and remodeling, Alox12 overexpression exacerbated MIR injury. Remarkably, pharmacological inhibition of ALOX12 significantly reduced cardiac injury in mice, pigs, and monkeys. Unexpectedly, ALOX12 promotes cardiomyocyte injury beyond its enzymatic activity and production of 12-HETE but also by its suppression of AMPK activity via a direct interaction with its upstream kinase TAK1. Taken together, our study demonstrates that ALOX12 is a novel AMPK upstream regulator in the post-MIR heart and that it represents a conserved therapeutic target for the treatment of myocardial reperfusion injury.

Truncated TEAD-binding protein of TAZ inhibits glioma survival through the induction of apoptosis and repression of epithelial-mesenchymal transition.

Transcriptional coactivator with PDZ-binding motif (TAZ), a Hippo pathway downstream effector, promotes tumor progression by serving as a transcriptional coactivator with TEAD. Here, we introduced a new construct which can express the TEAD-binding domain of TAZ protein (TAZBD), and determined its antitumor effect in malignant glioma both in vitro and in vivo. We first observed that TAZ was upregulated in glioma tissues and related to malignant clinicopathologic characteristic, indicating the crucial role of TAZ during glioma progression. In U87 and U251 cells, TAZBD expression increased the proportion of apoptotic cells, and suppressed the colony formation and tumorigenicity. Further, TAZBD also decreased cell metastasis through the repression of epithelial-mesenchymal transition. The mechanistic study showed that TAZBD suppression of glioma cells was predominantly through blocking the TAZ-TEAD complex formation by competing with endogenous TAZ. Thus, the gene therapy of malignant glioma through blocking TAZ-TEAD complex by TAZBD may provide a new way for the targeted therapy of glioma.

Integrated Omics Reveals Tollip as an Regulator and Therapeutic Target for Hepatic Ischemia-Reperfusion Injury in Mice.

Hepatic ischemia-reperfusion (IR) injury is the leading cause of liver dysfunction and failure after liver resection or transplantation and lacks effective therapeutic strategies. Here, we applied a systematic proteomic analysis to identify the prominent contributors to IR-induced liver damage and promising therapeutic targets for this condition. Based on an unbiased proteomic analysis, we found that toll-interacting protein (Tollip) expression was closely correlated with the hepatic IR process. RNA sequencing analysis and phenotypic examination showed a dramatically alleviated hepatic IR injury by Tollip deficiency both in vivo and in hepatocytes. Mechanistically, Tollip interacts with apoptosis signal-regulating kinase 1 (ASK1) and facilitates the recruitment of tumor necrosis factor receptor-associated factor 6 (TRAF6) to ASK1, leading to enhanced ASK1 N-terminal dimerization and the subsequent activation of downstream mitogen-activated protein kinase (MAPK) signaling. Furthermore, the Tollip methionine and phenylalanine motif and TRAF6 ubiquitinating activity are required for Tollip-regulated ASK1-MAPK axis activation. Conclusion: Tollip is a regulator of hepatic IR injury by facilitating ASK1 N-terminal dimerization and the resultant c-Jun N-terminal kinase/p38 signaling activation. Inhibiting Tollip or its interaction with ASK1 might be promising therapeutic strategies for hepatic IR injury.

An ALOX12-12-HETE-GPR31 signaling axis is a key mediator of hepatic ischemia-reperfusion injury.

Hepatic ischemia-reperfusion (IR) injury is a common clinical issue lacking effective therapy and validated pharmacological targets. Here, using integrative 'omics' analysis, we identified an arachidonate 12-lipoxygenase (ALOX12)-12-hydroxyeicosatetraenoic acid (12-HETE)-G-protein-coupled receptor 31 (GPR31) signaling axis as a key determinant of the hepatic IR process. We found that ALOX12 was markedly upregulated in hepatocytes during ischemia to promote 12-HETE accumulation and that 12-HETE then directly binds to GPR31, triggering an inflammatory response that exacerbates liver damage. Notably, blocking 12-HETE production inhibits IR-induced liver dysfunction, inflammation and cell death in mice and pigs. Furthermore, we established a nonhuman primate hepatic IR model that closely recapitulates clinical liver dysfunction following liver resection. Most strikingly, blocking 12-HETE accumulation effectively attenuated all pathologies of hepatic IR in this model. Collectively, this study has revealed previously uncharacterized metabolic reprogramming involving an ALOX12-12-HETE-GPR31 axis that functionally determines hepatic IR procession. We have also provided proof of concept that blocking 12-HETE production is a promising strategy for preventing and treating IR-induced liver damage.

The expression of seven 14-3-3 isoforms in human meningioma.

14-3-3 proteins comprise a large family of highly conserved, acidic polypeptides, expressed in all eukaryotic organisms, with highest concentration found in the brain. Multiple isoforms of 14-3-3 proteins have been shown to play an essential role in regulating differentiation, proliferation and transformation. In the previous study, the expression levels of all seven 14-3-3 isoforms were examined in astrocytoma. However, the expression of seven 14-3-3 isoforms in meningioma still remains unknown. This study is the first examination of 14-3-3 isoforms in three grades of meningioma by immunohistochemistry. 14-3-3epsilon, zeta and theta were specifically expressed in meningioma, and their expression levels increased with the increase of pathological grade of meningioma. The 14-3-3 eta, beta, gamma and sigma isoforms were negatively expressed in meningioma. In conclusion, The 14-3-3 epsilon, zeta and theta may be involved in tumorigenesis of meningioma and be efficient markers for predicting the degree of malignancy in meningioma.

The expression and significance of HIF-1alpha and GLUT-3 in glioma.

HIF-1alpha plays an indispensable role in tumor formation and histogenesis. Target genes involved in glucose transport are acutely transactivated by HIF-1alpha. GLUT-3 protein is the rate-limiting factor related to glucose transport, which is classified as brain-type glucose transporter. This study was the initial one aiming to probe into the co-expression and clinical significance of HIF-1alpha and GLUT-3 in glioma. One hundred and twenty cases of glioma tissues and ten human normal cerebral tissues decompressed in glioma excision were examined using immunohistochemistry and Western blot. The expression of HIF-1alpha and GLUT-3 increased gradually with the increase of pathological grade of glioma, respectively. There was significant difference in the expression of HIF-1alpha and GLUT-3 in every two groups, respectively. There was a positive correlation between HIF-1alpha and GLUT-3. In conclusion, the expression of HIF-1alpha and GLUT-3 in glioma was correlated significantly with tumors' pathological grade, which can be taken as a pair of useful markers for predicting the biological behavior of glioma.