Processed coffee alleviates DSS-induced colitis in mice

Background: Coffee is one of the most widely consumed beverages in the world and it has been demonstrated that it has important therapeutic activities not only because of its caffeine content but also owing to the presence of other biologically active small molecules such as chlorogenic acid, trigonelline and cyclopentadiones. However, chlorogenic acid is degraded into catechol, pyrogallol and hydroxyhydroquinone, which are thought to induce irritation of the gastric mucosa. To reduce the content of irritant compounds processing methods have been developed prior to roasting the coffee beans.Objectives: The aim of this study was to study the anti-inflammatory and gastro-protective effects of processed coffee (Idee-Kaffee) on in LPS-treated human primary monocytes and in a murine model of colon inflammation (IBD model).Results: In this study we have analyzed the effects on inflammatory events in cultured cells and in mice drinking a commercially available processed coffee. The processed coffee inhibited lipopolysaccharide (LPS)-induced proinflammatory cytokines such as interleukin (IL)-1β, tumor necrosis factor (TNF)α, IL-6 and IL-8, and other inflammatory mediators such as prostaglandin (PG)E2 and 8-isoprostane in cultured human primary monocytes. Oral administration of dissolved processed coffee, i.e., in its usual beverage form, improved greatly the adverse macroscopic and histological features of dextran sodium sulfate (DSS)-induced colitis in mice in a dose-dependent manner. Processed coffee not only largely prevented DSS-induced colitis but also dramatically suppressed in vivo NF-ϰB and STAT3 activities through inhibition of IϰBα and STAT3 phosphorylation. Furthermore, this soluble coffee bean extract reduced the expression of proinflammatory cytokines TNFα, IL-11, and IL-6 and the expression of cyclooxygenase (COX)-2 in colonic tissues.Conclusions: This work identified processed coffee as an anti-inflammatory beverage with the capacity to reduce substantially DSS-induced colitis as well as the colitis-associated cellular inflammatory events. Keywords: coffee, Inflammatory Bowel Disease, NF-ϰB, STAT3, cytokines

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The impact of indole-3-lactic acid on immature intestinal innate immunity and development: a transcriptomic analysis

Scientific Reports ◽

10.1038/s41598-021-87353-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Wuyang Huang ◽

Ky Young Cho ◽

Di Meng ◽

W. Allan Walker

Keyword(s):

Lactic Acid ◽

Mechanistic Model ◽

Transcriptomic Analysis ◽

Dependent Manner ◽

Protective Effects ◽

Very Preterm Infants ◽

Anti Inflammatory ◽

The Impact

AbstractAn excessive intestinal inflammatory response may have a role in the pathogenesis of necrotizing enterocolitis (NEC) in very preterm infants. Indole-3-lactic acid (ILA) of breastmilk tryptophan was identified as the anti-inflammatory metabolite involved in probiotic conditioned media from Bifidobacteria longum subsp infantis. This study aimed to explore the molecular endocytic pathways involved in the protective ILA effect against inflammation. H4 cells, Caco-2 cells, C57BL/6 pup and adult mice were used to compare the anti-inflammatory mechanisms between immature and mature enterocytes in vitro and in vivo. The results show that ILA has pleiotropic protective effects on immature enterocytes including anti-inflammatory, anti-viral, and developmental regulatory potentials in a region-dependent and an age-dependent manner. Quantitative transcriptomic analysis revealed a new mechanistic model in which STAT1 pathways play an important role in IL-1β-induced inflammation and ILA has a regulatory effect on STAT1 pathways. These studies were validated by real-time RT-qPCR and STAT1 inhibitor experiments. Different protective reactions of ILA between immature and mature enterocytes indicated that ILA’s effects are developmentally regulated. These findings may be helpful in preventing NEC for premature infants.

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The N-Terminal Domain of Thrombomodulin Sequesters HMGB1: A Novel Anti-Inflammatory Mechanism.

Blood ◽

10.1182/blood.v104.11.3435.3435 ◽

2004 ◽

Vol 104 (11) ◽

pp. 3435-3435

Author(s):

Kazuhiro Abeyama ◽

Yasushi Yoshimoto ◽

Ikuro Maruyama

Keyword(s):

Protein C ◽

Statistical Significance ◽

Dependent Manner ◽

Protective Effects ◽

Binding Studies ◽

Terminal Domain ◽

Anti Inflammatory ◽

Dose Dependent

Abstract Thrombomodulin (TM) is an endothelial anticoagulant cofactor that promotes thrombin-mediated formation of activated protein C (APC), the latter an enzyme with potent anti-coagulant and anti-inflammatory properties. We have found that the N-terminal, lectin-like domain (D1) of thrombomodulin has unique anti-inflammatory properties. Thrombomodulin, via D1, binds high mobility group-B1 DNA binding protein (HMGB1), a factor closely associated with necrotic cell damage following its release from the nucleus, thereby preventing leukocyte activation in vitro, and ultraviolet radiation-induced cutaneous inflammation and lipopolysaccharide-induced lethality in vivo. Our data also demonstrate anti-inflammatory properties of a peptide spanning the D1 domain of TM and suggest its therapeutic potential. These findings highlight a novel mechanism through which an endothelial cofactor, TM, suppresses inflammation; i.e., sequestration of mediators thereby preventing their interaction with cell surface receptors on effector cells in the vasculature. Results: TM binds HMGB1 and prevents expression of pro-inflammatory activity. Our co-culture studies of leukocytes and HUVEC, and results in the cutaneous irritation model suggested that early release of a mediator, such as HMGB1, might contribute importantly to cellular activation in inflammation at later time points. In this context, TM might have the ability to decrease HMGB1-mediated inflammatory events. Binding studies using surface plasmon resonance (SPR), performed to directly assess the interaction of TM and immobilized HMGB1, demonstrated dose-dependent binding in the nanomolar range (Kd ~232 nM). Furthermore, addition of rhs-TM decreased, in a dose-dependent manner, the binding of HMGB1 to RAGE through the its N-terminal domain, but not anti-coagulant domain. TM and the N-terminal-derived TM peptide have anti-inflammatory effects in settings where HMGB1 is a likely key mediator. In HMGB1-mediated skin inflammation model, systemic administration of rhs-TM, its lectin-like domain and sRAGE resulted in a significant blunting of the inflammatory response. In contrast, the effect of anti-coagulant domain, although showing a trend toward decreased ear swelling, did not achieve statistical significance (anticoagulant domain has anti-inflammatory effects in vivo that probably reflect its ability to support thrombin-mediated activation of protein C; the latter does not occur in vitro after inactivation of the protein C zymogen by heat treatment). In view of recent data suggesting a link between HMGB1 released from injured tissue and endotoxin-induced lethality in mice, we also tested whether rhs-TM and its lectin-like domain might also have protective effects in this model. We employed a dose of intraperitoneal (IP) LPS (10 mg/kg) resulting in 100% lethality by 96 hrs. Systemic (IP) treatment of animals with anti-HMGB1 IgY had a protective effect with respect to lethality at 4 days, whereas the same regimen of nonimmune IgY was without effect. Similarly, IP administration of rhs-TM and its N-teminal lectin domain, but not anti-coagulant domain had complete protective effects compared with anti-HMGB1 IgY. Conclusion: Our findings have elucidated an unexpected anti-inflammatory property of TM residing in the D1 domain, namely binding of HMGB1.

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Protective Effects of Lentinan Against Lipopolysaccharide-Induced Mastitis in Mice

Frontiers in Pharmacology ◽

10.3389/fphar.2021.755768 ◽

2021 ◽

Vol 12 ◽

Author(s):

Huifang Yin ◽

Guanhong Xue ◽

Ailing Dai ◽

Haichong Wu

Keyword(s):

Mammary Epithelial ◽

Economic Losses ◽

Dependent Manner ◽

Protective Effects ◽

Dairy Farmers ◽

Worldwide Production ◽

Tnf Α ◽

Anti Inflammatory

Mastitis is a worldwide production disease in dairy cows, which mainly affects milk yield, causing huge economic losses to dairy farmers. Lentinan is a kind of polysaccharide extracted from Lentinus edodes, which has no toxicity and possesses various pharmacological activities including antibacterial and immunomodulatory effects. Therefore, the anti-inflammatory function of lentinan on LPS-stimulated mastitis was carried out, and the mechanism involved was explored. In vivo, lentinan greatly reduced LPS-stimulated pathological injury, myeloperoxidase (MPO) activity, and the proinflammatory factor production (TNF-α and IL-1β) in mice. Further study was performed to determine the activation of the Wnt/β-catenin pathway during LPS stimulation. These results suggested that LPS-induced activation of the Wnt/β-catenin pathway was suppressed by lentinan administration. In vitro, we observed that the mouse mammary epithelial cell (mMEC) viability was not affected by lentinan treatment. As expected, LPS increased the TNF-α and IL-1β protein secretion and the activation of the Wnt/β-catenin pathway that was inhibited by lentinan administration in a dose-dependent manner in mMECs. Conclusively, lentinan exerts the anti-inflammatory function in LPS-stimulated mastitis via inhibiting the activation of the Wnt/β-catenin pathway. Thus, the results of our study also gave an insight that lentinan may serve as a potential treatment for mastitis.

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Trans-Cinnamaldehyde Inhibits IL-1β-Stimulated Inflammation in Chondrocytes by Suppressing NF-κB and p38-JNK Pathways and Exerts Chondrocyte Protective Effects in a Rat Model of Osteoarthritis

BioMed Research International ◽

10.1155/2019/4039472 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12 ◽

Cited By ~ 6

Author(s):

Tianwei Xia ◽

Runzi Gao ◽

Guowei Zhou ◽

Jinzhu Liu ◽

Jinsheng Li ◽

...

Keyword(s):

Cell Viability ◽

Cartilage Degradation ◽

Cartilage Destruction ◽

Dependent Manner ◽

Protective Effects ◽

Monosodium Iodoacetate ◽

Anti Inflammatory ◽

Inflammatory Effect

Objective. Trans-cinnamaldehyde (TCA), a compound from Cinnamomum cassia Presl, has been reported to have anti-inflammatory effect. However, its effect on cartilage degradation in osteoarthritis is unclear. This study is designed to examine the effects of TCA on cartilage in vitro and in vivo. Material and Methods. SW1353 cells and human primary chondrocytes were treated with varying concentrations of TCA (2-20 μg/ml) for 2 h followed by IL-1β stimulation. Cell viability was examined by the MTT assay. Expression of MMP-1, MMP-3, MMP-13, ADAMTS-4, and ADAMTS-5 was examined by Western blot and RT-qPCR. Monosodium iodoacetate (MIA)-induced OA was established in rats to assess the chondrocyte protective effects of intraperitoneal injection of TCA (50 mg/kg). Results. TCA at a concentration of 10 μg/ml had no significant effect on cell viability. MMP-1, MMP-3, MMP-13, ADAMTS-4, and ADAMTS-5 were decreased by TCA 2-10 μg/ml in a dose-dependent manner (all P<0.05). Pretreatment with TCA decreased the degradation of IκBα and increased the expression of p-IκBα, indicating that NF-κB inactivation was induced by TCA in IL-1β-stimulated SW1353 cells. Pretreatment with TCA decreased the levels of p-p38 and p-JNK, while the levels of p-ERK were not significantly affected. TCA 10 μg/ml significantly decreased expression levels of MMP-1, MMP-3, MMP-13, ADAMTS-4, and ADAMTS-5. In vivo results showed that TCA alleviated cartilage destruction and the OARSI scores. Conclusion. TCA possesses anti-inflammatory effect in vitro and exerts chondrocyte protective effects in vivo, in which NF-κB and p38-JNK were involved.

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Protective Effect of Pyrus ussuriensis Maxim. Extract against Ethanol-Induced Gastritis in Rats

Antioxidants ◽

10.3390/antiox10030439 ◽

2021 ◽

Vol 10 (3) ◽

pp. 439

Author(s):

Naila Boby ◽

Muhammad Aleem Abbas ◽

Eon-Bee Lee ◽

Zi-Eum Im ◽

Walter H. Hsu ◽

...

Keyword(s):

Therapeutic Option ◽

Adenosine Monophosphate ◽

Ethanol Ingestion ◽

Dependent Manner ◽

Protective Effects ◽

Gastric Mucosal Lesions ◽

Cellular Degeneration ◽

Mucosal Lesions ◽

Pyrus Ussuriensis Maxim

Pyrus ussuriensis Maxim (Korean pear) has been used for hundreds of years as a traditional herbal medicine for asthma, cough, and atopic dermatitis in Korea and China. Although it was originally shown to possess anti-inflammatory, antioxidant, and antiatopic properties, its gastroprotective effects have not been investigated. In the present study, we evaluated the protective effects of Pyrus ussuriensis Maxim extract (PUE) against ethanol-induced gastritis in rats. The bioactive compound profile of PUE was determined by gas chromatography mass spectroscopy (GC-MS) and high-performance liquid chromatography (HPLC). The gastroprotection of PUE at different doses (250 and 500 mg/kg body weight) prior to ethanol ingestion was evaluated using an in vivo gastritis rat model. Several endpoints were evaluated, including gastric mucosal lesions, cellular degeneration, intracellular damage, and immunohistochemical localization of leucocyte common antigen. The gastric mucosal injury and ulcer score were determined by evaluating the inflamed gastric mucosa and by histological examination. To identify the mechanisms of gastroprotection by PUE, antisecretory action and plasma prostaglandin E2 (PGE2), gastric mucosal cyclic adenosine monophosphate (cAMP), and histamine levels were measured. PUE exhibited significant antioxidant effects with IC50 values of 56.18 and 22.49 µg/mL for 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′- azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) inhibition (%), respectively. In addition, GC/MS and HPLC analyses revealed several bioactive compounds of PUE. Pretreatment with PUE significantly (P < 0.05) decreased the ulcer index by preventing gastric mucosal lesions, erosion, and cellular degeneration. An immunohistochemical analysis revealed that PUE markedly attenuated leucocyte infiltration in a dose-dependent manner. The enhancement of PGE2 levels and attenuation of cAMP levels along with the inhibition of histamine release following PUE pretreatment was associated with the cytoprotective and healing effects of PUE. In contrast, the downregulation of the H+/K+ ATPase pathway as well as muscarinic receptor (M3R) and histamine receptor (H2R) inhibition was also involved in the gastroprotective effects of PUE; however, the expression of cholecystokinin-2 receptors (CCK2R) was unchanged. Finally, no signs of toxicity were observed following PUE treatment. Based on our results, we conclude that PUE represents an effective therapeutic option to reduce the risk of gastritis and warrants further study.

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Farnesol-Loaded Liposomes Protect the Epidermis and Dermis from PM2.5-Induced Cutaneous Injury

International Journal of Molecular Sciences ◽

10.3390/ijms22116076 ◽

2021 ◽

Vol 22 (11) ◽

pp. 6076

Author(s):

Yu-Chiuan Wu ◽

Wei-Yun Chen ◽

Chun-Yin Chen ◽

Sheng I. Lee ◽

Yu-Wen Wang ◽

...

Keyword(s):

Chronic Inflammation ◽

Water Solubility ◽

Antibacterial Properties ◽

Hair Follicles ◽

Protective Effects ◽

Cutaneous Injury ◽

Anti Inflammatory ◽

High Concentrations ◽

Acute And Chronic Inflammation

Particulate matter with aerodynamic diameter ≤2.5 μm (PM2.5) increases oxidative stress through free radical generation and incomplete volatilization. In addition to affecting the respiratory system, PM2.5 causes aging- and inflammation-related damage to skin. Farnesol (Farn), a natural benzyl semiterpene, possesses anti-inflammatory, antioxidative, and antibacterial properties. However, because of its poor water solubility and cytotoxicity at high concentrations, the biomedical applications of Farn have been limited. This study examined the deleterious effects of PM2.5 on the epidermis and dermis. In addition, Farn-encapsulated liposomes (Lipo-Farn) and gelatin/HA/xanthan gel containing Lipo-Farn were prepared and applied in vivo to repair and alleviate PM2.5-induced damage and inflammation in skin. The prepared Lipo-Farn was 342 ± 90 nm in diameter with an encapsulation rate of 69%; the encapsulation significantly reduced the cytotoxicity of Farn. Lipo-Farn exhibited a slow-release rate of 35% after 192 h of incubation. The half-maximal inhibitory concentration of PM2.5 was approximately 850 μg/mL, and ≥400 μg/mL PM2.5 significantly increased IL-6 production in skin fibroblasts. Severe impairment in the epidermis and hair follicles and moderate impairment in the dermis were found in the groups treated with post-PM2.5 and continuous subcutaneous injection of PM2.5. Acute and chronic inflammation was observed in the skin in both experimental categories in vivo. Treatment with 4 mM Lipo-Farn largely repaired PM2.5-induced injury in the epidermis and dermis, restored injured hair follicles, and alleviated acute and chronic inflammation induced by PM2.5 in rat skin. In addition, treatment with 4 mM pure Farn and 2 mM Lipo-Farn exerted moderate reparative and anti-inflammatory effects on impaired skin. The findings of the current study indicate the therapeutic and protective effects of Lipo-Farn against various injuries caused by PM2.5 in the pilosebaceous units, epidermis, and dermis of skin.

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Targeting a Lipid Desaturation Enzyme, SCD1, Selectively Eliminates Colon Cancer Stem Cells through the Suppression of Wnt and NOTCH Signaling

Cells ◽

10.3390/cells10010106 ◽

2021 ◽

Vol 10 (1) ◽

pp. 106

Author(s):

Yeongji Yu ◽

Hyejin Kim ◽

SeokGyeong Choi ◽

JinSuh Yu ◽

Joo Yeon Lee ◽

...

Keyword(s):

Colon Cancer ◽

Notch Signaling ◽

Cultured Cells ◽

Pcr Analysis ◽

Marker Genes ◽

Dependent Manner ◽

Lipid Desaturation ◽

Novel Target

The elimination of the cancer stem cell (CSC) population may be required to achieve better outcomes of cancer therapy. We evaluated stearoyl-CoA desaturase 1 (SCD1) as a novel target for CSC-selective elimination in colon cancer. CSCs expressed more SCD1 than bulk cultured cells (BCCs), and blocking SCD1 expression or function revealed an essential role for SCD1 in the survival of CSCs, but not BCCs. The CSC potential selectively decreased after treatment with the SCD1 inhibitor in vitro and in vivo. The CSC-selective suppression was mediated through the induction of apoptosis. The mechanism leading to selective CSC death was investigated by performing a quantitative RT-PCR analysis of 14 CSC-specific signaling and marker genes after 24 and 48 h of treatment with two concentrations of an inhibitor. The decrease in the expression of Notch1 and AXIN2 preceded changes in the expression of all other genes, at 24 h of treatment in a dose-dependent manner, followed by the downregulation of most Wnt- and NOTCH-signaling genes. Collectively, we showed that not only Wnt but also NOTCH signaling is a primary target of suppression by SCD1 inhibition in CSCs, suggesting the possibility of targeting SCD1 against colon cancer in clinical settings.

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Heart rate reduction with ivabradine promotes shear stress-dependent anti-inflammatory mechanisms in arteries

Thrombosis and Haemostasis ◽

10.1160/th16-03-0214 ◽

2016 ◽

Vol 116 (07) ◽

pp. 181-190 ◽

Cited By ~ 13

Author(s):

Luong Le ◽

Hayley Duckles ◽

Torsten Schenkel ◽

Marwa Mahmoud ◽

Jordi Tremoleda ◽

...

Keyword(s):

Heart Rate ◽

Shear Stress ◽

Carotid Arteries ◽

Vascular Inflammation ◽

Protective Effects ◽

En Face ◽

Inflammatory Activation ◽

Anti Inflammatory ◽

Stress Dependent

SummaryBlood flow generates wall shear stress (WSS) which alters endothelial cell (EC) function. Low WSS promotes vascular inflammation and atherosclerosis whereas high uniform WSS is protective. Ivabradine decreases heart rate leading to altered haemodynamics. Besides its cardio-protective effects, ivabradine protects arteries from inflammation and atherosclerosis via unknown mechanisms. We hypothesised that ivabradine protects arteries by increasing WSS to reduce vascular inflammation. Hypercholesterolaemic mice were treated with ivabradine for seven weeks in drinking water or remained untreated as a control. En face immunostaining demonstrated that treatment with ivabradine reduced the expression of pro-inflammatory VCAM-1 (p<0.01) and enhanced the expression of anti-inflammatory eNOS (p<0.01) at the inner curvature of the aorta. We concluded that ivabradine alters EC physiology indirectly via modulation of flow because treatment with ivabradine had no effect in ligated carotid arteries in vivo, and did not influence the basal or TNFα-induced expression of inflammatory (VCAM-1, MCP-1) or protective (eNOS, HMOX1, KLF2, KLF4) genes in cultured EC. We therefore considered whether ivabradine can alter WSS which is a regulator of EC inflammatory activation. Computational fluid dynamics demonstrated that ivabradine treatment reduced heart rate by 20 % and enhanced WSS in the aorta. In conclusion, ivabradine treatment altered haemodynamics in the murine aorta by increasing the magnitude of shear stress. This was accompanied by induction of eNOS and suppression of VCAM-1, whereas ivabradine did not alter EC that could not respond to flow. Thus ivabradine protects arteries by altering local mechanical conditions to trigger an anti-inflammatory response.

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Protective Effect of Phillyrin on Lethal LPS-Induced Neutrophil Inflammation in Zebrafish

Cellular Physiology and Biochemistry ◽

10.1159/000484192 ◽

2017 ◽

Vol 43 (5) ◽

pp. 2074-2087 ◽

Cited By ~ 19

Author(s):

Liling Yang ◽

Xiangjun Zhou ◽

Weijuan Huang ◽

Qin Fang ◽

Jianlan Hu ◽

...

Keyword(s):

Signalling Pathway ◽

Dependent Manner ◽

Zebrafish Model ◽

Lps Challenge ◽

Cell Counts ◽

Tnf Α ◽

Forsythia Suspensa ◽

Anti Inflammatory

Background/Aims: Forsythia suspensa Vahl. (Oleaceae) fruits are widely used in traditional Chinese medicine to treat pneumonia, typhoid, dysentery, ulcers and oedema. Antibacterial and anti-inflammatory activities have been reported for phillyrin (PHN), the main ingredient in Forsythia suspensa Vahl fruits, in vitro. However, the underlying mechanisms in vivo remain poorly defined. In this study, we discovered that PHN exerted potent anti-inflammatory effects in lethal LPS-induced neutrophil inflammation by suppressing the MyD88-dependent signalling pathway in zebrafish. Methods: LPS-yolk microinjection was used to induce a lethal LPS-infected zebrafish model. The effect of PHN on the survival of zebrafish challenged with lethal LPS was evaluated using survival analysis. The effect of PHN on neutrophil inflammation grading in vivo was assessed by tracking neutrophils with a transgenic line. The effects of PHN on neutrophil production and migration were analysed by SB+ cell counts during consecutive hours after modelling. Additionally, key cytokines and members of the MyD88 signalling pathway that are involved in inflammatory response were detected using quantitative RT-PCR. To assess gene expression changes during consecutive hours after modelling, the IL-1β, IL-6, TNF-α, MyD88, TRIF, ERK1/2, JNK, IκBa and NF-κB expression levels were measured. Results: PHN could protect zebrafish against a lethal LPS challenge in a dose-dependent manner, as indicated by decreased neutrophil infltration, reduced tissue necrosis and increased survival rates. Up-regulated IL-1β, IL-6 and TNF-α expression also showed the same tendencies of depression by PHN. Critically, PHN significantly inhibited the LPS-induced activation of MyD88, IκBa, and NF-κB but did not affect the expression of ERK1/2 MAPKs or JNK MAPKs in LPS-stimulated zebrafish. Additionally, PHN regulated the MyD88/IκBα/NF-κB signalling pathway by controlling IκBα, IL-1β, IL-6, and TNF-α expression. Conclusion: This study provides a rationale for the clinical application of PHN as an anti-inflammatory agent.

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Activation of the Akt1-CREB pathway promotes RNF146 expression to inhibit PARP1-mediated neuronal death

Science Signaling ◽

10.1126/scisignal.aax7119 ◽

2020 ◽

Vol 13 (663) ◽

pp. eaax7119

Author(s):

Hyojung Kim ◽

Jisoo Park ◽

Hojin Kang ◽

Seung Pil Yun ◽

Yun-Song Lee ◽

...

Keyword(s):

Chlorogenic Acid ◽

Transcriptional Activation ◽

Dopaminergic Neurons ◽

Cultured Cells ◽

Intraperitoneal Administration ◽

Neuronal Loss ◽

Postmortem Brain ◽

Dependent Manner ◽

Gene Encoding ◽

Creb Pathway

Progressive degeneration of dopaminergic neurons characterizes Parkinson’s disease (PD). This neuronal loss occurs through diverse mechanisms, including a form of programmed cell death dependent on poly(ADP-ribose) polymerase-1 (PARP1) called parthanatos. Deficient activity of the kinase Akt1 and aggregation of the protein α-synuclein are also implicated in disease pathogenesis. Here, we found that Akt1 suppressed parthanatos in dopaminergic neurons through a transcriptional mechanism. Overexpressing constitutively active Akt1 in SH-SY5Y cells or culturing cells with chlorogenic acid (a polyphenol found in coffee that activates Akt1) stimulated the CREB-dependent transcriptional activation of the gene encoding the E3 ubiquitin ligase RNF146. RNF146 inhibited PARP1 not through its E3 ligase function but rather by binding to and sequestering PAR, which enhanced the survival of cultured cells exposed to the dopaminergic neuronal toxin 6-OHDA or α-synuclein aggregation. In mice, intraperitoneal administration of chlorogenic acid activated the Akt1-CREB-RNF146 pathway in the brain and provided neuroprotection against both 6-OHDA and combinatorial α-synucleinopathy in an RNF146-dependent manner. Furthermore, dysregulation of the Akt1-CREB pathway was observed in postmortem brain samples from patients with PD. The findings suggest that therapeutic restoration of RNF146 expression, such as by activating the Akt1-CREB pathway, might halt neurodegeneration in PD.

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