scholarly journals Selective Immunomodulation of Inflammatory Pathways in Keratinocytes by the Janus Kinase (JAK) Inhibitor Tofacitinib: Implications for the Employment of JAK-Targeting Drugs in Psoriasis

2018 ◽  
Vol 2018 ◽  
pp. 1-18 ◽  
Author(s):  
Martina Morelli ◽  
Claudia Scarponi ◽  
Laura Mercurio ◽  
Francesco Facchiano ◽  
Sabatino Pallotta ◽  
...  

IFN-γ and IL-22 are deeply involved in the pathogenesis of psoriasis, as they boost the expression of inflammatory genes and alter proliferative and differentiative programs in keratinocytes. The JAK1/JAK2/STAT1 and JAK1/TYK2/STAT3 pathways triggered by IFN-γ and IL-22, respectively, are aberrantly activated in psoriasis, as highlighted by the peculiar STAT1 and STAT3 signatures in psoriatic skin lesions. To limit the detrimental consequences of IFN-γ and IL-22 excessive stimulation, psoriatic keratinocytes activate suppressor of cytokine signaling (SOCS)1 and SOCS3, which in turn dampen molecular signaling by inhibiting JAK1 and JAK2. Thus, JAK targeting appears to be a reasonable strategy to treat psoriasis. Tofacitinib is an inhibitor of JAK proteins, which, similarly to SOCS, impedes JAK phosphorylation. In this study, we evaluated the immunomodulatory effects of tofacitinib on epidermal keratinocytes in in vitro and in vivo models of psoriasis. We demonstrated the selectivity of tofacitinib inhibitory action on IFN-γ and IL-22, but not on TNF-γ or IL-17 proinflammatory signaling, with suppressed expression of IFN-γ-dependent inflammatory genes, and restoration of normal proliferative and differentiative programs altered by IL-22 in psoriatic keratinocyte cultures. Tofacitinib also potently reduced the psoriasiform phenotype in the imiquimod-induced murine model of psoriasis. Finally, we found that tofacitinib mimics SOCS1 or SOCS3 activities, as it impaired the same molecular pathways in IFN-γ or IL-22-activated keratinocytes.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jatin Sharma ◽  
Teresa D. Collins ◽  
Tracoyia Roach ◽  
Shiwangi Mishra ◽  
Brandon K. Lam ◽  
...  

AbstractAutoimmune diseases are driven largely by a pathogenic cytokine milieu produced by aberrantly activated lymphocytes. Many cytokines, including interferon gamma (IFN-γ), utilize the JAK/STAT pathway for signal propagation. Suppressor of Cytokine Signaling-1 (SOCS1) is an inducible, intracellular protein that regulates IFN-γ signaling by dampening JAK/STAT signaling. Using Fas deficient, MRL/MpJ-Faslpr/J (MRL/lpr) mice, which develop lupus-like disease spontaneously, we tested the hypothesis that a peptide mimic of the SOCS1 kinase inhibitory region (SOCS1-KIR) would inhibit lymphocyte activation and modulate lupus-associated pathologies. Consistent with in vitro studies, SOCS1-KIR intraperitoneal administration reduced the frequency, activation, and cytokine production of memory CD8+ and CD4+ T lymphocytes within the peripheral blood, spleen, and lymph nodes. In addition, SOCS1-KIR administration reduced lymphadenopathy, severity of skin lesions, autoantibody production, and modestly reduced kidney pathology. On a cellular level, peritoneal SOCS1-KIR administration enhanced Foxp3 expression in total splenic and follicular regulatory T cells, reduced the effector memory/naïve T lymphocyte ratio for both CD4+ and CD8+ cells, and reduced the frequency of GL7+ germinal center enriched B cells. Together, these data show that SOCS1-KIR treatment reduced auto-reactive lymphocyte effector functions and suggest that therapeutic targeting of the SOCS1 pathway through peptide administration may have efficacy in mitigating autoimmune pathologies.


2021 ◽  
Vol 12 ◽  
Author(s):  
Maaria Palmroth ◽  
Krista Kuuliala ◽  
Ritva Peltomaa ◽  
Anniina Virtanen ◽  
Antti Kuuliala ◽  
...  

ObjectiveCurrent knowledge on the actions of tofacitinib on cytokine signaling pathways in rheumatoid arthritis (RA) is based on in vitro studies. Our study is the first to examine the effects of tofacitinib treatment on Janus kinase (JAK) - signal transducer and activator of transcription (STAT) pathways in vivo in patients with RA.MethodsSixteen patients with active RA, despite treatment with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs), received tofacitinib 5 mg twice daily for three months. Levels of constitutive and cytokine-induced phosphorylated STATs in peripheral blood monocytes, T cells and B cells were measured by flow cytometry at baseline and three-month visits. mRNA expression of JAKs, STATs and suppressors of cytokine signaling (SOCS) were measured from peripheral blood mononuclear cells (PBMCs) by quantitative PCR. Association of baseline signaling profile with treatment response was also investigated.ResultsTofacitinib, in csDMARDs background, decreased median disease activity score (DAS28) from 4.4 to 2.6 (p < 0.001). Tofacitinib treatment significantly decreased cytokine-induced phosphorylation of all JAK-STAT pathways studied. However, the magnitude of the inhibitory effect depended on the cytokine and cell type studied, varying from 10% to 73% inhibition following 3-month treatment with tofacitinib. In general, strongest inhibition by tofacitinib was observed with STAT phosphorylations induced by cytokines signaling through the common-γ-chain cytokine receptor in T cells, while lowest inhibition was demonstrated for IL-10 -induced STAT3 phosphorylation in monocytes. Constitutive STAT1, STAT3, STAT4 and STAT5 phosphorylation in monocytes and/or T cells was also downregulated by tofacitinib. Tofacitinib treatment downregulated the expression of several JAK-STAT pathway components in PBMCs, SOCSs showing the strongest downregulation. Baseline STAT phosphorylation levels in T cells and monocytes and SOCS3 expression in PBMCs correlated with treatment response.ConclusionsTofacitinib suppresses multiple JAK-STAT pathways in cytokine and cell population specific manner in RA patients in vivo. Besides directly inhibiting JAK activation, tofacitinib downregulates the expression of JAK-STAT pathway components. This may modulate the effects of tofacitinib on JAK-STAT pathway activation in vivo and explain some of the differential findings between the current study and previous in vitro studies. Finally, baseline immunological markers associate with the treatment response to tofacitinib.


2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Jian-Mei Li ◽  
Wei Wang ◽  
Chen-Yu Fan ◽  
Ming-Xing Wang ◽  
Xian Zhang ◽  
...  

Fructose-induced hyperinsulinemia is associated with insulin compensative secretion and predicts the onset of type 2 diabetes. In this study, we investigated the preservation of dietary flavonoid quercetin on pancreaticβ-cell mass and function in fructose-treated rats and INS-1β-cells. Quercetin was confirmed to reduce serum insulin and leptin levels and blockade islet hyperplasia in fructose-fed rats. It also prevented fructose-inducedβ-cell proliferation and insulin hypersecretion in INS-1β-cells. High fructose increased forkhead box protein O1 (FoxO1) expressionsin vivoandin vitro, which were reversed by quercetin. Quercetin downregulated Akt and FoxO1 phosphorylation in fructose-fed rat islets and increased the nuclear FoxO1 levels in fructose-treated INS-1β-cells. The elevated Akt phosphorylation in fructose-treated INS-1β-cells was also restored by quercetin. Additionally, quercetin suppressed the expression of pancreatic and duodenal homeobox 1 (Pdx1) and insulin gene (Ins1 and Ins2)in vivoandin vitro. In fructose-treated INS-1β-cells, quercetin elevated the reduced janus kinase 2/signal transducers and activators of transcription 3 (Jak2/Stat3) phosphorylation and suppressed the increased suppressor of cytokine signaling 3 (Socs3) expression. These results demonstrate that quercetin protectsβ-cell mass and function under high-fructose induction through improving leptin signaling and preserving pancreatic Akt/FoxO1 activation.


2006 ◽  
Vol 291 (5) ◽  
pp. R1399-R1405 ◽  
Author(s):  
S. Gentili ◽  
J. S. Schwartz ◽  
M. J. Waters ◽  
I. C. McMillen

The fetal pituitary-adrenal axis plays a key role in the fetal response to intrauterine stress and in the timing of parturition. The fetal sheep adrenal gland is relatively refractory to stimulation in midgestation (90–120 days) before the prepartum activation, which occurs around 135 days gestation (term = 147 ± 3 days). The mechanisms underlying the switch from adrenal quiescence to activation are unclear. Therefore, we have investigated the expression of suppressor of cytokine signaling-3 (SOCS-3), a putative inhibitor of tissue growth in the fetal sheep adrenal between 50 and 145 days gestation and in the adrenal of the growth-restricted fetal sheep in late gestation. SOCS-3 is activated by a range of cytokines, including prolactin (PRL), and we have, therefore, determined whether PRL administered in vivo or in vitro stimulates SOCS-3 mRNA expression in the fetal adrenal in late gestation. There was a decrease ( P < 0.005) in SOCS-3 expression in the fetal adrenal between 54 and 133 days and between 141 and 144 days gestation. Infusion of the dopaminergic agonist, bromocriptine, which suppressed fetal PRL concentrations but did not decrease adrenal SOCS-3 mRNA expression. PRL administration, however, significantly increased adrenal SOCS-3 mRNA expression ( P < 0.05). Similarly, there was an increase ( P < 0.05) in SOCS-3 mRNA expression in adrenocortical cells in vitro after exposure to PRL (50 ng/ml). Placental and fetal growth restriction had no effect on SOCS-3 expression in the adrenal during late gestation. In summary, the decrease in the expression of the inhibitor SOCS-3 after 133 days gestation may be permissive for a subsequent increase in fetal adrenal growth before birth. We conclude that factors other than PRL act to maintain adrenal SOCS-3 mRNA expression before 133 days gestation but that acute elevations of PRL can act to upregulate adrenal SOCS-3 expression in the sheep fetus during late gestation.


Antioxidants ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 754
Author(s):  
Sara La Manna ◽  
Laura Lopez-Sanz ◽  
Susana Bernal ◽  
Luna Jimenez-Castilla ◽  
Ignacio Prieto ◽  
...  

The chronic activation of the Janus kinase/signal transducer and activator of the transcription (JAK/STAT) pathway is linked to oxidative stress, inflammation and cell proliferation. Suppressors of cytokine signaling (SOCS) proteins negatively regulate the JAK/STAT, and SOCS1 possesses a small kinase inhibitory region (KIR) involved in the inhibition of JAK kinases. Several studies showed that KIR-SOCS1 mimetics can be considered valuable therapeutics in several disorders (e.g., diabetes, neurological disorders and atherosclerosis). Herein, we investigated the antioxidant and atheroprotective effects of PS5, a peptidomimetic of KIR-SOCS1, both in vitro (vascular smooth muscle cells and macrophages) and in vivo (atherosclerosis mouse model) by analyzing gene expression, intracellular O2•− production and atheroma plaque progression and composition. PS5 was revealed to be able to attenuate NADPH oxidase (NOX1 and NOX4) and pro-inflammatory gene expression, to upregulate antioxidant genes and to reduce atheroma plaque size, lipid content and monocyte/macrophage accumulation. These findings confirm that KIR-SOCS1-based drugs could be excellent antioxidant agents to contrast atherosclerosis.


2018 ◽  
Vol 315 (4) ◽  
pp. G443-G453 ◽  
Author(s):  
Xia Lin ◽  
Li Chen ◽  
Haiyan Li ◽  
Yu Liu ◽  
Yanhong Guan ◽  
...  

Liver regeneration after two-thirds partial hepatectomy (PH) is a clinically significant repair process for restoring proper liver architecture. Although microRNA-155 (miR-155) has been found to serve as a crucial microRNA regulator that controls liver cell function and proliferation, little is known about its specific role in the regenerating liver. Using a mouse model with miR-155 overexpression or miR-155 knockout, we investigated the molecular mechanisms of miR-155 in liver regeneration. We found a marked induction of miR-155 in C57BL/6 mice after PH. Furthermore, RL-m155 mice showed enhanced liver regeneration as a result of accelerated progression of hepatocytes into the cell cycle, mainly through an increase in cyclin levels. However, proliferation of hepatocytes was delayed in miR-155-deficient livers. Expression of suppressor of cytokine signaling 1 (SOCS1) was dramatically downregulated in the process of liver regeneration, and enhancement of SOCS1 contributed to impaired proliferation of hepatocytes. Additionally, in vitro and in vivo experiments showed that adenovirus- or adeno-associated virus-mediated overexpression of SOCS1 attenuated improved liver regeneration induced by miR-155 overexpression. Our study shows that miR-155 is a pro-proliferative regulator in liver regeneration by facilitating the cell cycle and directly targeting SOCS1. NEW & NOTEWORTHY Our findings suggest a microRNA-155 (miR-155)-mediated positive regulation pattern in liver regeneration. A series of in vivo and in vitro studies showed that miR-155 upregulation enhanced partial hepatectomy-induced proliferation of hepatocytes by promoting the cell cycle without inducing DNA damage or apoptosis. Suppressor of cytokine signaling 1, a target gene of miR-155, antagonized the proliferation-promoting effect of miR-155. Therefore, pharmacological intervention targeting miR-155 may be therapeutically beneficial in various liver diseases.


2008 ◽  
Vol 180 (9) ◽  
pp. 6270-6278 ◽  
Author(s):  
Yu Liu ◽  
Keith N. Stewart ◽  
Eileen Bishop ◽  
Carylyn J. Marek ◽  
David C. Kluth ◽  
...  

2015 ◽  
Vol 36 (5) ◽  
pp. 1743-1752 ◽  
Author(s):  
Xiaoming Qi ◽  
Jianqiang Li ◽  
Changbo Zhou ◽  
Chunlei Lv ◽  
Min Tian

Background/Aims: An increasing number of studies show that microRNAs (miRNAs) play crucial roles in nasopharyngeal carcinoma (NPC) tumorigenesis. The aim of our study was to investigate the biological roles and mechanisms of miR-142-3p in NPC. Methods: miR-142-3p expression was examined in NPC specimens and nasopharyngitis biopsy samples by quantitative real-time PCR. The biological functions of miR-142-3p were studied using a series of in vitro and in vivo approaches. Results: miR-142-3p is over-expressed in NPC tissues and cell lines. Knockdown of miR-142-3p significantly inhibited cell proliferation and cell cycle progression in vitro, and suppressed tumor growth in a mouse model. Suppressor of cytokine signaling 6 (SOCS6) was identified as a direct target of miR-142-3p, and miR-142-3p down-regulated the expression of SOCS6 by directly binding to its 3′untranslated region (UTR). Knockdown of SOCS6 abrogated the effects of miR-142-3p down-regulation. Conclusion: These findings indicate that miR-142-3p regulates NPC development by down-regulating SOCS6 expression and suggest that modulation of miR-142-3p expression could be a therapeutic strategy for NPC.


1996 ◽  
Vol 184 (5) ◽  
pp. 2007-2012 ◽  
Author(s):  
D Bruch-Gerharz ◽  
K Fehsel ◽  
C Suschek ◽  
G Michel ◽  
T Ruzicka ◽  
...  

Psoriasis is a common chronic skin disease mediated by cellular immune mechanisms and characterized by an intense neutrophil cell infiltrate and proliferative activation of epidermal keratinocytes. We have previously described the expression of the inducible nitric oxide synthase (iNOS) in epidermal keratinocytes of psoriatic skin lesions. In this study, the role of iNOS in psoriatic inflammation was explored ex vivo in psoriatic skin biopsies and in vitro in primary cultures of human keratinocytes. Messenger RNA for the iNOS enzyme (iNOS mRNA) was detected by reverse transcriptase polymerase chain reaction in skin biopsies from patients with psoriasis, but not in skin specimens from patients with atopic eczema or from healthy volunteers. As demonstrated by in situ hybridization and immunohistochemistry, expression of iNOS mRNA and its gene product was localized to the epidermal keratinocytes of psoriatic skin lesions. In situ hybridization further revealed a complete colocalization of mRNA expression for iNOS with interleukin (IL) 8 receptor-specific mRNA either in the basal germinative cell layer or at focal sites of ongoing neutrophil inflammation in suprabasal cell layers. Because psoriatic keratinocytes have previously been shown to express mRNA transcripts for IL-8, it seemed reasonable to hypothesize that iNOS expression could be induced in an autocrine loop by IL-8. This hypothesis was substantiated by our in vitro experiments showing that a combination of IL-8 and interferon gamma induces the expression of iNOS-specific mRNA and of the functional enzyme in cultured human keratinocytes. These results suggest an important role for iNOS in concert with IL-8 and its receptor early during the formation of psoriatic lesions.


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