Mesencephalic Astrocyte-Derived Neurotrophic Factor (MANF) Protects Against Neuronal Apoptosis via Activation of Akt/MDM2/p53 Signaling Pathway in a Rat Model of Intracerebral Hemorrhage.
Xu Weilin,Gao Liansheng,Li Tao,Zheng Jingwei,Shao Anwen,Zhang Jianmin
Frontiers in molecular neuroscience
Neuronal apoptosis plays key roles in secondary brain injury caused by intracerebral hemorrhage (ICH). This study first reported the role of mesencephalic astrocyte-derived neurotrophic factor (MANF) in alleviating secondary brain injury through anti-apoptosis in rat model of ICH. The recombinant human-MANF (rh-MANF) and selective Akt inhibitor MK2206 was administrated intracerebroventricularly 1 h after ICH. Brain water content, behavioral assessment, BBB (blood brain barrier) leakage was evaluated 24 h after the induction of ICH. Western blot analysis was used to evaluate the expression level of target proteins (MANF, mouse 3T3 cell double-minute 2 (MDM2), P53, Akt, Bcl-2, Bax, and caspase-3). Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) was applied to evaluate the neuronal cell death. Besides, whether MANF was expressed in neurons was verified with double immunofluorescence staining. The results suggested that the level of MANF, and its downstream proteins, Akt, MDM2 was upregulated and reached peak at 24 h after ICH. MANF was mainly expressed in neurons. The administration of rh-MANF could significantly increase the level of p-Akt, p-MDM2, Bcl/Bax ratio, but reduce the expression of p53, caspase-3 and neuronal death, thus ameliorate the neurological functions at 24 h after ICH. However, these effects of rh-MANF could be obviously reversed by MK2206. MANF could exert its neuronal anti-apoptotic effects via Akt/MDM2/P53 pathways. Therefore, MANF could be a valuable drug target in the treatment of ICH.
10.3389/fnmol.2018.00176
Hepatocyte-derived MANF is protective for rifampicin-induced cholestatic hepatic injury via inhibiting ATF4-CHOP signal activation.
Wang Peng,Yang Yi,Pang Gaozong,Zhang Chaoyi,Wei Chuansheng,Tao Xiaofang,Liu Jun,Xu Jianming,Zhang Weiping,Shen Yuxian
Free radical biology & medicine
Rifampicin (RFP) has been known to be potentially hepatotoxic and often used as an inducer of cholestatic hepatic injury. Here we found that mesencephalic astrocyte-derived neurotrophic factor (MANF), an endoplasmic reticulum (ER) stress inducible protein, is a protector in RFP-induced liver injury. In cholestatic hepatic injury mice induced by RFP, the liver/body ratio and the levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bile acid (TBA), total bilirubin (TBIL), and direct bilirubin (DBIL) were significantly increased. Meanwhile, the protein and mRNA levels of MANF were remarkably elevated in the liver injury mice. In hepatocyte-specific MANF knockout (HKO) mice, an extra increase in the liver/body ratio and serum ALT, AST, ALP, TBA, TBIL, and DBIL levels was detected after treatment with RFP. In addition, recombinant human MANF (rhMANF) treatment efficiently reduced the liver/body ratio and serum ALT, AST, ALP, TBA, TBIL, and DBIL levels in RFP-induced liver injury mice. Furthermore, we found there is an increase in the number of the apoptotic cells, detected by TUNEL staining in the liver tissues of HKO mice. Meanwhile, the protein levels of C/EBP-homologous protein (CHOP), Ki67, and the proliferating cell nuclear antigen (PCNA), as well as the mRNA level of Ki67 were elevated after treated with RFP, and these parameters were increased more significantly in HKO mice than that in wild type (WT) controls in RFP-induced liver injury. The rhMANF treatment can rescue the cell apoptosis and reduce the protein and mRNA levels of CHOP, Ki67, and PCNA elevated by MANF deletion and RFP. In HKO mice, immunoglobulin heavy chain binding protein (BIP) and activating transcription factor 4 (ATF4) were predominantly increased after treatment with RFP, which were reduced by rhMANF treatment. Therefore, we conclude that hepatocyte-derived MANF is protective for RFP-induced cholestatic hepatic injury via inhibiting ATF4-CHOP signal activation and subsequent cell apoptosis.
10.1016/j.freeradbiomed.2020.10.028
MANF serves as a novel hepatocyte factor to promote liver regeneration after 2/3 partial hepatectomy via doubly targeting Wnt/β-catenin signaling.
Cell death & disease
Liver regeneration is an intricate pathophysiological process that has been a subject of great interest to the scientific community for many years. The capacity of liver regeneration is very critical for patients with liver diseases. Therefore, exploring the mechanisms of liver regeneration and finding good ways to improve it are very meaningful. Mesencephalic astrocyte-derived neurotrophic factor (MANF), a member of newly identified neurotrophic factors (NTFs) family, extensively expresses in the liver and has demonstrated cytoprotective effects during ER stress and inflammation. However, the role of MANF in liver regeneration remains unclear. Here, we used hepatocyte-specific MANF knockout (MANF) mice to investigate the role of MANF in liver regeneration after 2/3 partial hepatectomy (PH). Our results showed that MANF expression was up-regulated in a time-dependent manner, and the peak level of mRNA and protein appeared at 24 h and 36 h after 2/3 PH, respectively. Notably, MANF knockout delayed hepatocyte proliferation, and the peak proliferation period was delayed by 24 h. Mechanistically, our in vitro results showed that MANF physically interacts with LRP5 and β-catenin, two essential components of Wnt/β-catenin pathway. Specifically, as a cofactor, MANF binds to the extracellular segment of LRP5 to activate Wnt/β-catenin signaling. On the other hand, MANF interacts with β-catenin to stabilize cytosolic β-catenin level and promote its nuclear translocation, which further enhance the Wnt/β-catenin signaling. We also found that MANF knockout does not affect the c-Met/β-catenin complex after 2/3 PH. In summary, our study confirms that MANF may serve as a novel hepatocyte factor that is closely linked to the activation of the Wnt/β-catenin pathway via intracellular and extracellular targets.
10.1038/s41419-024-07069-8
MANF ameliorates DSS-induced mouse colitis via restricting Ly6CCX3CR1 macrophage transformation and suppressing CHOP-BATF2 signaling pathway.
Acta pharmacologica Sinica
Mesencephalic astrocyte-derived neurotrophic factor (MANF), an endoplasmic reticulum stress-inducible secreting protein, has evolutionarily conserved immune-regulatory function that contributes to the negative regulation of inflammation in macrophages. In this study, we investigated the profiles of MANF in the macrophages of the patients with active inflammatory bowel disease (IBD) and the mice with experimental colitis, which was induced in both myeloid cell-specific MANF knockout mice and wild-type mice by 3% dextran sodium sulfate (DSS) for 7 days. We found that MANF expression was significantly increased in intestinal macrophages from both the mice with experimental colitis and patients with active IBD. DSS-induced colitis was exacerbated in myeloid cell-specific MANF knockout mice. Injection of recombinant human MANF (rhMANF, 10 mg·kg·d, i.v.) from D4 to D6 significantly ameliorated experimental colitis in DSS-treated mice. More importantly, MANF deficiency in myeloid cells resulted in a dramatic increase in the number of Ly6CCX3CR proinflammatory macrophages in colon lamina propria of DSS-treated mice, and the proinflammatory cytokines and chemokines were upregulated as well. Meanwhile, we demonstrated that MANF attenuated Th17-mediated immunopathology by inhibiting BATF2-mediated innate immune response and downregulating CXCL9, CXCL10, CXCL11 and IL-12p40; MANF functioned as a negative regulator in inflammatory macrophages via inhibiting CHOP-BATF2 signaling pathway, thereby protecting against DSS-induced mouse colitis. These results suggest that MANF ameliorates colon injury by negatively regulating inflammatory macrophage transformation, which shed light on a potential therapeutic target for IBD.
10.1038/s41401-022-01045-8
MANF/EWSR1/ANXA6 pathway might as the bridge between hypolipidemia and major depressive disorder.
Translational psychiatry
Major depressive disorder (MDD) involves changes in lipid metabolism, but previous findings are contradictory. Mesencephalic astrocyte-derived neurotrophic factor (MANF) is considered to be a regulator of lipid metabolism. To date, the function of MANF has been studied in many brain disorders, but not in MDD. Therefore, to better understand the role of lipids in MDD, this study was conducted to examine lipid levels in the serum of MDD patients and to investigate the potential function of MANF in MDD. First, the data on total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglyceride (TG) in serum from 354 MDD patients and 360 healthy controls (HCs) were collected and analyzed. The results showed that there were significantly lower concentrations of TC and LDL-C in MDD patients compared with HCs, and TC levels were positively correlated with LDL-C levels. Bioinformatics analysis indicated that MANF/EWSR1/ANXA6 pathway might serve as the connecting bridge through which hypolipidemia played a functional role in MDD. Second, to verify this hypothesis, serum samples were collected from 143 MDD patients, and 67 HCs to measure the levels of MANF, EWSR1, and ANXA6 using ELISA kits. The results showed that compared to HCs, MDD patients had a significantly lower level of MANF and higher levels of ANXA6 and EWSR1, and these molecules were significantly correlated with both TC level and Hamilton Depression Rating Scales (HDRS) score. In addition, a discriminative model consisting of MANF, EWSR1, and ANXA6 was identified. This model was capable of distinguishing MDD subjects from HCs, yielded an area under curve of 0.9994 in the training set and 0.9569 in the testing set. Taken together, our results suggested that MANF/EWSR1/ANXA6 pathway might act as the bridge between hypolipidemia and MDD, and these molecules held promise as potential biomarkers for MDD.
10.1038/s41398-022-02287-0
Feeding-induced hepatokine, Manf, ameliorates diet-induced obesity by promoting adipose browning via p38 MAPK pathway.
Wu Tong,Liu Qinhui,Li Yanping,Li Hong,Chen Lei,Yang Xuping,Tang Qin,Pu Shiyun,Kuang Jiangying,Li Rui,Huang Ya,Zhang Jinhang,Zhang Zijing,Zhou Jian,Huang Cuiyuan,Zhang Guorong,Zhao Yingnan,Zou Min,Jiang Wei,Mo Li,He Jinhan
The Journal of experimental medicine
Activating beige adipocytes in white adipose tissue (WAT) to increase energy expenditure is a promising strategy to combat obesity. We identified that mesencephalic astrocyte-derived neurotrophic factor (Manf) is a feeding-induced hepatokine. Liver-specific Manf overexpression protected mice against high-fat diet-induced obesity and promoted browning of inguinal subcutaneous WAT (iWAT). Manf overexpression in liver was also associated with decreased adipose inflammation and improved insulin sensitivity and hepatic steatosis. Mechanistically, Manf could directly promote browning of white adipocytes via the p38 MAPK pathway. Blockade of p38 MAPK abolished Manf-induced browning. Consistently, liver-specific Manf knockout mice showed impaired iWAT browning and exacerbated diet-induced obesity, insulin resistance, and hepatic steatosis. Recombinant Manf reduced obesity and improved insulin resistance in both diet-induced and genetic obese mouse models. Finally, we showed that circulating Manf level was positively correlated with BMI in humans. This study reveals the crucial role of Manf in regulating thermogenesis in adipose tissue, representing a potential therapeutic target for obesity and related metabolic disorders.
10.1084/jem.20201203