Revisiting Structure-activity Relationships: Unleashing the potential of selective Janus kinase 1 inhibitors.

Janus kinases (JAKs), a kind of non-receptor tyrosine kinases, the function has been implicated in the regulation of cell proliferation, differentiation and apoptosis, immune, inflammatory response and malignancies. Among them, JAK1 represents an essential target for modulating cytokines involved in inflammation and immune function. Rheumatoid arthritis, atopic dermatitis, ulcerative colitis and psoriatic arthritis are areas where approved JAK1 drugs have been applied for the treatment. In the review, we provided a brief introduction to JAK1 inhibitors in market and clinical trials. The structures of high active JAK1 compounds (IC50 ≤ 0.1 nM) were highlighted, with primary focus on structure-activity relationship and selectivity. Moreover, the druggability processes of approved drugs and high active compounds were analyzed. In addition, the issues involved in JAK1 compounds clinical application as well as strategies to surmount these challenges, were discussed.

Myelin oligodendrocyte glycoprotein reactive Th17 cells drive Janus Kinase 1 dependent transcriptional reprogramming in astrocytes and alter cell surface cytokine receptor profiles during experimental autoimmune encephalomyelitis.

Multiple sclerosis (MS) is an autoimmune demyelinating disease affecting the central nervous system (CNS). T helper (Th) 17 cells are involved in the pathogenesis of MS and its animal model of experimental autoimmune encephalomyelitis (EAE) by infiltrating the CNS and producing effector molecules that engage resident glial cells. Among these glial cells, astrocytes have a central role in coordinating inflammatory processes by responding to cytokines and chemokines released by Th17 cells. In this study, we examined the impact of pathogenic Th17 cells on astrocytes in vitro and in vivo. We identified that Th17 cells reprogram astrocytes by driving transcriptomic changes partly through a Janus Kinase (JAK)1-dependent mechanism, which included increased chemokines, interferon-inducible genes, and cytokine receptors. In vivo, we observed a region-specific heterogeneity in the expression of cell surface cytokine receptors on astrocytes, including those for IFN-γ, IL-1, TNF-α, IL-17, TGFß, and IL-10. Additionally, these receptors were dynamically regulated during EAE induced by adoptive transfer of myelin-reactive Th17 cells. This study overall provides evidence of Th17 cell reprogramming of astrocytes, which may drive changes in the astrocytic responsiveness to cytokines during autoimmune neuroinflammation.

Peripheral cytokine interleukin-10 alleviates perihematomal edema after intracerebral hemorrhage via interleukin-10 receptor/JAK1/STAT3 signaling.

AIMS: The extent of perihematomal edema following intracerebral hemorrhage (ICH) significantly impacts patient prognosis, and disruption of the blood-brain barrier (BBB) exacerbates perihematomal edema. However, the role of peripheral IL-10 in mitigating BBB disruption through pathways that link peripheral and central nervous system signals remains poorly understood. METHODS: Recombinant IL-10 was administered to ICH model mice via caudal vein injection, an IL-10-inhibiting adeno-associated virus and an IL-10 receptor knockout plasmid were delivered intraventricularly, and neurobehavioral deficits, perihematomal edema, BBB disruption, and the expression of JAK1 and STAT3 were evaluated. RESULTS: Our study demonstrated that the peripheral cytokine IL-10 mitigated BBB breakdown, perihematomal edema, and neurobehavioral deficits after ICH and that IL-10 deficiency reversed these effects, likely through the IL-10R/JAK1/STAT3 signaling pathway. CONCLUSIONS: Peripheral IL-10 has the potential to reduce BBB damage and perihematomal edema following ICH and improve patient prognosis.

Baricitinib protects ICIs-related myocarditis by targeting JAK1/STAT3 to regulate Macrophage polarization.

PURPOSE: The emergence of immune checkpoint inhibitors (ICIs) has revolutionized cancer treatment, but these drugs can also cause severe immune-related adverse effects (irAEs), including myocarditis. Researchers have become interested in exploring ways to mitigate this side effect, and one promising avenue is the use of baricitinib, a Janus kinase inhibitor known to have anti-inflammatory properties. This study aimed to examine the potential mechanism by which baricitinib in ICIs-related myocarditis. METHODS: To establish an ICIs-related myocarditis model, BALB/c mice were administered murine cardiac troponin I (cTnI) peptide and anti-mouse programmed death 1 (PD-1) antibodies. Subsequently, baricitinib was administered to the mice via intragastric administration. Echocardiography, HE staining, and Masson staining were performed to evaluate myocardial functions, inflammation, and fibrosis. Immunofluorescence was used to detect macrophages in the cardiac tissue of the mice.In vitro experiments utilized raw264.7 cells to induce macrophage polarization using anti-PD-1 antibodies. Different concentrations of baricitinib were applied to assess cell viability, and the release of pro-inflammatory cytokines was measured. The activation of the JAK1/STAT3 signaling pathway was evaluated through western blot analysis. RESULTS: Baricitinib demonstrated its ability to improve cardiac function and reduce cardiac inflammation, as well as fibrosis induced by ICIs. Mechanistically, baricitinib treatment promoted the polarization of macrophages towards the M2 phenotype. In vitro and in vivo experiments showed that anti-PD-1 promoted the release of inflammatory factors. However, treatment with baricitinib significantly inhibited the phosphorylation of JAK1 and STAT3. Additionally, the use of RO8191 reversed the effects of baricitinib, further confirming our findings. CONCLUSION: Baricitinib demonstrated its potential as a protective agent against ICIs-related myocarditis by modulating macrophage polarization. These findings provide a solid theoretical foundation for the development of future treatments for ICIs-related myocarditis.

Evaluating the pharmacokinetics of upadacitinib for the treatment of moderate-to-severe Crohn's disease.

INTRODUCTION: Janus kinases (JAK) are enzymes involved in signaling pathways that activate the immune system. Upadacitinib, an oral small molecule, is the first JAK inhibitor approved by FDA and EMA for the treatment of moderately to severely active Crohn's disease (CD), following successful phase II and III trials. Compared to other JAK inhibitors, upadacitinib has a high selectivity toward JAK1. This characteristic could improve its efficacy and safety. AREAS COVERED: This review provides an overview of the available knowledge on the pharmacokinetics of upadacitinib as induction and maintenance therapy for CD. EXPERT OPINION: The approval of newer targeted small molecules drug, including JAK inhibitors, marked a significant advancement in terms of effectiveness. In fact, the oral administration, the rapid absorption, the excellent bioavailability and the short serum time of maximum concentration are some of the advantages compared to biologics. The selective inhibition of JAK1 by upadacitinib allows for high efficacy while maintaining a reliable safety profile.

Annona squamosa Fruit Extract Ameliorates Lead Acetate-Induced Testicular Injury by Modulating JAK-1/STAT-3/SOCS-1 Signaling in Male Rats.

Lead (Pb) is a common pollutant that is not biodegradable and gravely endangers the environment and human health. Annona squamosa fruit has a wide range of medicinal uses owing to its phytochemical constituents. This study evaluated the effect of treatment with A. squamosa fruit extract (ASFE) on testicular toxicity induced in male rats by lead acetate. The metal-chelating capacity and phytochemical composition of ASFE were determined. The LD50 of ASFE was evaluated by probit analysis. Molecular docking simulations were performed using Auto Dock Vina. Forty male Sprague Dawley rats were equally divided into the following groups: Gp1, a negative control group; Gp2, given ASFE (350 mg/kg body weight (b. wt.)) (1/10 of LD50); Gp3, given lead acetate (PbAc) solution (100 mg/kg b. wt.); and Gp4, given PbAc as in Gp3 and ASFE as in Gp2. All treatments were given by oro-gastric intubation daily for 30 days. Body weight changes, spermatological parameters, reproductive hormone levels, oxidative stress parameters, and inflammatory biomarkers were evaluated, and molecular and histopathological investigations were performed. The results showed that ASFE had promising metal-chelating activity and phytochemical composition. The LD50 of ASFE was 3500 mg/kg b. wt. The docking analysis showed that quercetin demonstrated a high binding affinity for JAK-1 and STAT-3 proteins, and this could make it a more promising candidate for targeting the JAK-1/STAT-3 pathway than others. The rats given lead acetate had defective testicular tissues, with altered molecular, biochemical, and histological features, as well as impaired spermatological characteristics. Treatment with ASFE led to a significant mitigation of these dysfunctions and modulated the JAK-1/STAT-3/SOCS-1 axis in the rats.

Synthesis, Antiproliferative Activity and Molecular Docking Analysis of Both Enantiomerically Pure Decursin Derivatives as Anticancer Agents.

Using (S)-decursinol isolated from root of Angelica gigas Nakai (AGN), we semi-synthesized and evaluated a series of both enantiomerically pure decursin derivatives for their antiproliferative activities against A549 human lung cancer cells. All synthesized compounds showed a broad spectrum of inhibitory activities against the growth of A549 cells. Especially, compound (S)-2d with (E)-(furan-3-yl)acryloyl group showed the most potent activity (IC50: 14.03 µM) against A549 cancer cells as compared with the reference compound, decursin (IC50: 43.55 µM) and its enantiomer, (R)-2d (IC50: 151.59 µM). Western blotting assays indicated that (S)-2d more strongly inhibited Janus kinase 1 (JAK1) and signal transducer and activator of transcription activation 3 (STAT3) phosphorylation than decursin in a dose-dependent manner, while having no effect on CXCR7 overexpression and total STAT3 level. In addition, (S)-2d induced cell cycle arrest at G1 phase and subsequent apoptotic cell death in A549 cancer cells. Our combined analysis of molecular docking studies and biological data suggests that the inhibition of JAK1 with (S)-2d resulted in loss of STAT3 phosphorylation and inhibition of cell growth in A549 cancer cells. These overall results strongly suggest that (S)-2d (MRC-D-004) as a novel JAK1 inhibitor may have therapeutic potential in the treatment of A549 human lung cancers by targeting the JAK1/STAT3 signaling pathway.

Intraintestinal Heterogeneity of Drug Target Expression in Inflammatory Bowel Disease.

OBJECTIVE: There has been no significant improvement in remission rate in inflammatory bowel disease (IBD) despite several new drugs being introduced in the past two decades. Post-treatment biopsies sometimes show histologic healing in some areas of the intestine while other areas within the same intestine continue to show active inflammation. The aim of this short descriptive study was to determine whether heterogeneous treatment response in IBD may be caused by heterogeneous expression of treatment targets within the same intestine. METHODS: Six cases of Crohn's disease and five cases of ulcerative colitis in which moderate to severe active inflammation was present in at least two biopsies from the same intestine obtained during the same endoscopy procedure were entered in the study. Sections were stained for TNFα and phospho-JAK1 (p-JAK1) using immunohistochemistry. Expression of TNFα and p-JAK1 was recorded as high when the staining intensity was moderate or high, or low when there was no or week staining. The number of eosinophils per high power field was counted in the area of peak density. RESULTS: Different sites within the same intestine from IBD patients with moderate to severe active inflammation may express different levels of TNFα and p-JAK1. For example, in one patient with Crohn's disease with histologically moderate to severe activity in biopsies from the ileum (site 1) and cecum (site 2), there was high expression of p-JAK1 and low TNFα in the ileum biopsy with the exact opposite in the cecum biopsy (low p-JAK1 and high TNFα expression). In this example neither small molecule drug targeting JAK1 nor anti-TNFα biologic given as single agent therapy would be expected to induce histologic remission in both actively inflamed sites in this patient. CONCLUSIONS: The heterogeneous expression of treatment targets within the same intestine may explain why some patients with IBD may not have complete remission on single drug. Studies are needed to determine whether assay for target expression in mucosal biopsies from IBD patients can help to optimize treatment selection.

A Novel JAK1 Inhibitor SHR0302 Combined With Prednisone for First-Line Treatment of Chronic Graft-Versus-Host Disease: A Phase I Clinical Trial.

Chronic graft-versus-host disease (cGVHD) is a potentially life-threatening complication after allogeneic hematopoietic stem cell transplantation. Standard steroid first-line treatment could not satisfy therapeutic needs due to limited efficacy. As a highly selective Janus kinase (JAK) 1 inhibitor, SHR0302 exhibits a reduced inhibition effect on JAK2 and might have less effect on hematopoiesis. This phase I clinical trial investigated the tolerability and safety of SHR0302 in combination with prednisone, and its early efficacy evidence as a potential first-line treatment to moderate/severe cGVHD. The standard 3 + 3 dose escalation was implemented to find the optimal dose of SHR0302. And prednisone was concurrently administrated with a dose of 1 mg/kg/d and then gradually tapered after 2 weeks. Eighteen patients were enrolled into the study. Grade ≥ 3 treatment-related adverse events were observed in 38.9% of patients. Only one patient developed DLT (grade ≥ 3 hypercholesterolemia) in the highest dose-level group who had pre-existing hypercholesterolemia. The maximum tolerated dose was not reached. No patient discontinued treatment due to AEs. Sixteen out of 18 patients were evaluable for responses, the ORR at week 4 and week 24 were 94.4 and 87.5%, respectively. Overall, the treatment of SHR0302 combined with prednisone was safe and well-tolerated, preliminary clinical results presented a high response for previously untreated cGVHD and a significant reduction in prednisone use in this study. A phase II trial will be conducted to further investigate its therapeutic effects clinically.

Fluoxetine attenuates chlorpyrifos-induced neuronal injury through the PPARγ, SIRT1, NF-κB, and JAK1/STAT3 signals.

Chlorpyrifos (CPF) is a widely used organophosphate insecticide in agriculture and homes. Exposure to organophosphates is associated with neurotoxicity. Fluoxetine (FLX) is a selective serotonin reuptake inhibitor (SSRI) that is widely prescribed for depression and anxiety disorders. Studies have shown that FLX has neuroprotective, anti-inflammatory, antioxidant, and antiapoptotic effects. The molecular mechanisms underlying FLX are not fully understood. This work aimed to investigate the potential neuroprotective effect of FLX on CPF-induced neurotoxicity and the underlying molecular mechanisms involved. Thirty-two rats were randomly divided into four groups: (I) the vehicle control group; (II) the FLX-treated group (10 mg/kg/day for 28 days, p.o); (III) the CPF-treated group (10 mg/kg for 28 days); and (IV) the FLX+CPF group. FLX attenuated CPF-induced neuronal injury, as evidenced by a significant decrease in Aß and p-Tau levels and attenuation of cerebral and hippocampal histological abrasion injury induced by CPF. FLX ameliorated neuronal oxidative stress, effectively reduced MDA production, and restored SOD and GSH levels through the coactivation of the PPARγ and SIRT1 proteins. FLX counteracted the neuronal inflammation induced by CPF by decreasing MPO, NO, TNF-α, IL-1ß, and IL-6 levels by suppressing NF-κB and JAK1/STAT3 activation. The antioxidant and anti-inflammatory properties of FLX help to prevent CPF-induced neuronal intoxication.

Hair growth-promoting effects of Enz_MoriL on human dermal papilla cells through modulation of the Wnt/ß-Catenin and JAK-STAT signaling pathways.

Enz_MoriL is a naturally occurring substance extracted from the leaves of Morus alba L. through enzymatic conversion. Historically, M. alba L. has been recognized for its potential to promote hair regrowth. However, the precise mechanism by which Enz_MoriL affects human hair follicle dermal papilla cells (hDPCs) remains unclear. The aim of this study was to investigate the molecular basis of Enz_MoriL's effect on hair growth in hDPCs. Interferon-gamma (IFN-γ) was used to examine the effects of Enz_MoriL on hDPCs during the anagen and catagen phases, as well as under conditions mimicking alopecia areata (AA). Enz_MoriL demonstrated the ability to promote cell proliferation in both anagen and catagen stages. It increased the levels of active ß-catenin in the catagen stage induced by IFN-γ, leading to its nuclear translocation. This effect was achieved by increasing the phosphorylation of GSK3ß and decreasing the expression of DKK-1. This stimulation induced proliferation in hDPCs and upregulated the expression of the Wnt family members 3a, 5a, and 7a at the transcript level. Additionally, Enz_MoriL suppressed JAK1 and STAT3 phosphorylation, contrasting with IFN-γ, which induced them in the catagen stage. In conclusion, Enz_MoriL directly induced signals for anagen re-entry into hDPCs by affecting the Wnt/ß-catenin pathway and enhancing the production of growth factors. Furthermore, Enz_MoriL attenuated and reversed the interferon-induced AA-like environment by blocking the JAK-STAT pathway in hDPCs.

The Janus kinase 1 is critical for pancreatic cancer initiation and progression.

Interleukin-6 (IL-6)-class inflammatory cytokines signal through the Janus tyrosine kinase (JAK)/signal transducer and activator of transcription (STAT) pathway and promote the development of pancreatic ductal adenocarcinoma (PDAC); however, the functions of specific intracellular signaling mediators in this process are less well defined. Using a ligand-controlled and pancreas-specific knockout in adult mice, we demonstrate in this study that JAK1 deficiency prevents the formation of KRASG12D-induced pancreatic tumors, and we establish that JAK1 is essential for the constitutive activation of STAT3, whose activation is a prominent characteristic of PDAC. We identify CCAAT/enhancer binding protein δ (C/EBPδ) as a biologically relevant downstream target of JAK1 signaling, which is upregulated in human PDAC. Reinstating the expression of C/EBPδ was sufficient to restore the growth of JAK1-deficient cancer cells as tumorspheres and in xenografted mice. Collectively, the findings of this study suggest that JAK1 executes important functions of inflammatory cytokines through C/EBPδ and may serve as a molecular target for PDAC prevention and treatment.

Subcutaneous administration of Stattic alleviates neuropathic pain by relieving inflammation in a mouse model of postherpetic neuralgia.

Stattic, a commercial inhibitor of STAT3, can drive the development of neuropathic pain. Exploring the connection between Stattic and JAK1/STAT3 signaling may facilitate the understanding of neuropathic pain caused by postherpetic neuralgia (PHN). In the current study, as crucial regulators of inflammation, STAT3 and its associated JAK1/STAT3 pathway were found to be upregulated and activated in the L4-L6 dorsal root ganglion (DRG) of mice in response to resiniferatoxin (RTX)-induced PHN, while subcutaneous administration of Stattic was found to downregulate STAT3 expression and phosphorylation in a PHN model. Stattic administration further attenuated hypersensitivity to mechanical and thermal stimuli in PHN mice, and alleviated inflammation and cell death in the L4-L6 DRG of mice. Overexpression of STAT3 via microinjection of a lentiviral-STAT3 overexpression vector reversed the abnormal decrease of STAT3 at both the mRNA and protein levels in the L4-6 DRGs of PHN mice and significantly promoted hypersensitivity to mechanical stimuli in the mice. Collectively, we found that subcutaneous static administration alleviated RTX-induced neuropathic pain by deactivating JAK1/STAT3 in mice.

[Protective effect of salidroside on renal damage in diabetic nephropathy mice by regulating RAGE/JAK1/STAT signaling pathway].

This study aims to investigate the protective effect of salidroside(SAL) on renal damage in diabetic nephropathy(DN) mice based on the receptor for advanced glycation end products/janus activated kinase 1/signal transduction and activator of transcription 3(RAGE/JAK1/STAT3) signaling pathway. The mouse DN model was established by high-fat/high-sucrose diets combined with intraperitoneal injection of streptozocin(STZ). Mice were randomly divided into normal group, model group, low-dose SAL group(20 mg·kg~(-1)), high-dose SAL group(100 mg·kg~(-1)), and metformin group(140 mg·kg~(-1)), with 12 mice in each group. After establishing the DN model, mice were given drugs or solvent intragastrically, once a day for consecutive 10 weeks. Body weight, daily water intake, and fasting blood glucose(FBG) were measured every two weeks. After the last dose, the glucose tolerance test was performed, and the samples of 24-hour urine, serum, and kidney tissue were collected. The levels of 24 hours urinary total protein(24 h-UTP), serum creatinine(Scr), blood urea nitrogen(BUN), triglyceride(TG), total cholesterol(TC), low density lipoprotein cholesterol(LDL-C), and high density lipoprotein cholesterol(HDL-C) were detected by biochemical tests. Periodic acid-schiff(PAS) staining was used to observe the pathological changes in the kidney tissue. The protein expressions of α-smooth muscle actin(α-SMA), vimentin, and advanced glycation end products(AGEs) in kidneys were detected by immunohistochemical staining. The activities of superoxide dismutase(SOD), catalase(CAT), glutathione peroxidase(GSH-PX), and the level of malondialdehyde(MDA) in kidneys were detected by using a corresponding detection kit. Enzyme-linked immunosorbent assay(ELISA) was used to detect the levels of AGEs, carboxymethyllysine(CML), and carboxyethyllysine(CEL) in serum. The protein expressions of RAGE and the phosphorylation level of JAK1 and STAT3 in kidneys were detected by Western blot. Compared with the normal group, the levels of FBG, the area under the curve of glucose(AUCG), water intake, kidney index, 24 h-UTP, tubular injury score, extracellular matrix deposition ratio of the renal glomerulus, the serum levels of Scr, BUN, TG, LDL-C, AGEs, CEL, and CML, the level of MDA, the protein expressions of α-SMA, vimentin, AGEs, and RAGE, and the phosphorylation level of JAK1 and STAT3 in kidney tissue were increased significantly(P<0.01), while the level of HDL-C in serum and the activity of SOD, CAT, and GSH-PX in kidney tissue were decreased significantly(P<0.01). Compared with the model group, the above indexes of the high-dose SAL group were reversed significantly(P<0.05 or P<0.01). In conclusion, this study suggests that SAL can alleviate oxidative stress and renal fibrosis by inhibiting the activation of AGEs-mediated RAGE/JAK1/STAT3 signaling axis, thus playing a potential role in the treatment of DN.

Reversible effects on female rat fertility with abrocitinib, a Janus kinase 1 inhibitor.

BACKGROUND: Abrocitinib is a Janus kinase (JAK) 1 selective inhibitor approved for the treatment of atopic dermatitis. Female reproductive tissues were unaffected in general toxicity studies, but an initial female rat fertility study resulted in adverse effects at all doses evaluated. A second rat fertility study was conducted to evaluate lower doses and potential for recovery. METHODS: This second study had 4 groups of 20 females each administered abrocitinib (0, 3, 10, or 70 mg/kg/day) 2 weeks prior to cohabitation through gestation day (GD) 7. In addition, 2 groups of 20 rats (0 or 70 mg/kg/day) were dosed for 3 weeks followed by a 4-week recovery period before mating. All mated females were evaluated on GD 14. RESULTS: No effects were observed at ≤10 mg/kg/day. At 70 mg/kg/day (29x human exposure), decreased pregnancy rate, implantation sites, and viable embryos were observed. All these effects reversed 4 weeks after the last dose. CONCLUSIONS: Based on these data and literature on the potential role of JAK signaling in implantation, we hypothesize that these effects may be related to JAK1 inhibition and, generally, that peri-implantation effects such as these, in the absence of cycling or microscopic changes in nonpregnant female reproductive tissues, are anticipated to be reversible.

Proximal protein landscapes of the type I interferon signaling cascade reveal negative regulation by PJA2.

Deciphering the intricate dynamic events governing type I interferon (IFN) signaling is critical to unravel key regulatory mechanisms in host antiviral defense. Here, we leverage TurboID-based proximity labeling coupled with affinity purification-mass spectrometry to comprehensively map the proximal human proteomes of all seven canonical type I IFN signaling cascade members under basal and IFN-stimulated conditions. This uncovers a network of 103 high-confidence proteins in close proximity to the core members IFNAR1, IFNAR2, JAK1, TYK2, STAT1, STAT2, and IRF9, and validates several known constitutive protein assemblies, while also revealing novel stimulus-dependent and -independent associations between key signaling molecules. Functional screening further identifies PJA2 as a negative regulator of IFN signaling via its E3 ubiquitin ligase activity. Mechanistically, PJA2 interacts with TYK2 and JAK1, promotes their non-degradative ubiquitination, and limits the activating phosphorylation of TYK2 thereby restraining downstream STAT signaling. Our high-resolution proximal protein landscapes provide global insights into the type I IFN signaling network, and serve as a valuable resource for future exploration of its functional complexities.

Involvement of the JAK-STAT pathway in the molecular landscape of tyrosine kinase fusion-negative hypereosinophilic syndromes: A nationwide CEREO study.

We investigated using a custom NGS panel of 149 genes the mutational landscape of 64 consecutive adult patients with tyrosine kinase fusion-negative hypereosinophilia (HE)/hypereosinophilic syndrome (HES) harboring features suggestive of myeloid neoplasm. At least one mutation was reported in 50/64 (78%) patients (compared to 8/44 (18%) patients with idiopathic HE/HES/HEUS used as controls; p < .001). Thirty-five patients (54%) had at least one mutation involving the JAK-STAT pathway, including STAT5B (n = 18, among which the hotspot N642H, n = 13), JAK1 (indels in exon 13, n = 5; V658F/L, n = 2), and JAK2 (V617F, n = 6; indels in exon 13, n = 2). Other previously undescribed somatic mutations were also found in JAK2, JAK1, STAT5B, and STAT5A, including three patients who shared the same STAT5A V707fs mutation and features consistent with primary polycythemia. Nearly all JAK-STAT mutations were preceded by (or associated with) myelodysplasia-related gene mutations, especially in RNA-splicing genes or chromatin modifiers. In multivariate analysis, neurologic involvement (hazard ratio [HR] 4.95 [1.87-13.13]; p = .001), anemia (HR 5.50 [2.24-13.49]; p < .001), and the presence of a high-risk mutation (as per the molecular international prognosis scoring system: HR 6.87 [2.39-19.72]; p < .001) were independently associated with impaired overall survival. While corticosteroids were ineffective in all treated JAK-STAT-mutated patients, ruxolitinib showed positive hematological responses including in STAT5A-mutated patients. These findings emphasize the usefulness of NGS for the workup of tyrosine kinase fusion-negative HE/HES patients and support the use of JAK inhibitors in this setting. Updated classifications could consider patients with JAK-STAT mutations and eosinophilia as a new "gene mutated-entity" that could be differentiated from CEL, NOS, and idiopathic HES.

Novel JAK Inhibitors to Reduce Graft-Versus-Host Disease after Allogeneic Hematopoietic Cell Transplantation in a Preclinical Mouse Model.

Allogeneic hematopoietic cell transplantation (allo-HCT) is a highly effective, well-established treatment for patients with various hematologic malignancies and non-malignant diseases. The therapeutic benefits of allo-HCT are mediated by alloreactive T cells in donor grafts. However, there is a significant risk of graft-versus-host disease (GvHD), in which the donor T cells recognize recipient cells as foreign and attack healthy organs in addition to malignancies. We previously demonstrated that targeting JAK1/JAK2, mediators of interferon-gamma receptor (IFNGR) and IL-6 receptor signaling, in donor T cells using baricitinib and ruxolitinib results in a significant reduction in GvHD after allo-HCT. Furthermore, we showed that balanced inhibition of JAK1/JAK2 while sparing JAK3 is important for the optimal prevention of GvHD. Thus, we have generated novel JAK1/JAK2 inhibitors, termed WU derivatives, by modifying baricitinib. Our results show that WU derivatives have the potential to mitigate GvHD by upregulating regulatory T cells and immune reconstitution while reducing the frequencies of antigen-presenting cells (APCs) and CD80 expression on these APCs in our preclinical mouse model of allo-HCT. In addition, WU derivatives effectively downregulated CXCR3 and T-bet in primary murine T cells. In summary, we have generated novel JAK inhibitors that could serve as alternatives to baricitinib or ruxolitinib.

Anti-inflammatory and anti-rheumatic effects of Phoenix dactylifera L. (date palm) seed by controlling cytokines and inhibiting JAK1/STAT3 pathway on CFA-induced arthritis rat and its phytochemical profiling.

ETHNOPHARMACOLOGICAL RELEVANCE: Phoenix dactylifera L. (date palm) seed is widely used in Arabian traditional medicine to alleviate several health problems including inflammatory conditions. The herbal tea of date palm seed has been consumed by rheumatoid patients to relief their symptoms. AIM OF THE STUDY: The purpose of this study was to investigate the claimed beneficial use of P. dactylifera L. (Sewy variety) seed (PDS) in the treatment of rheumatoid arthritis (RA) and its mechanism of action as well as to study its phytoconstituents. MATERIALS AND METHODS: The anti-inflammatory and anti-oxidative properties of the non-polar and the polar extracts of PDS were studied using Complete Freund's adjuvant (CFA)-induced arthritis rat model. Paw edema, body weight, total nitrate/nitrite NOX content and cytokine markers were evaluated to monitor the progress of arthritis. Also, histological examination and thermal analysis were conducted. The phytoconstituent profiles of non-polar and polar extracts of PDS were investigated using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). The multiple reactions monitoring mode (MRM) of liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) was used to quantify phenolic phytoconstituents in both extracts. RESULTS: According to the findings, the polar and non-polar PDS extracts kept body weight comparable to those of healthy individuals while considerably lowering paw swelling, edema, and neutrophil infiltration. It also reduced the levels of Nuclear Factor Kappa B (NF-κB), Tumor Necrosis Factor Alpha (TNF-α), Interleukin 22, Interleukin 23, Interferon (IFN), Interleukin 17, Interleukin 1ß, Interleukin 6, Interleukin 36, Janus Kinase 1 (JAK1), and Signal Transducer and Activator of Transcription 3 (STAT3). They also reduced the degenerative alterations caused by RA. Thermal research gave additional support for these findings. 83 phytoconstituents were identified in the non-polar PDS extract and 86 phytoconstituents were identified in the polar PDS extract. 74 of the identified phytoconstituents were common in both extracts. 33 phytoconstituents were identified here from P. dactylifera for the first time as far as we know. In MRM-LC-ESI-MS/MS analysis, the major phenolics in both extracts were chlorogenic acid, naringenin, and vanillin. Catechin was only detected in the non-polar PDS extract. On the other hand, apigenin, kaempferol, and hesperetin were only detected in the polar PDS extract. Generally, the polar PDS extract showed higher concentrations of the identified phenolics than the non-polar extract. CONCLUSIONS: The PDS extracts especially the non-polar extract showed significant anti-inflammatory and anti-oxidative properties in the CFA-induced arthritis rat model. PDS might be used to produce RA medicines.

Tofacitinib and peficitinib inhibitors of Janus kinase for autoimmune disease treatment: a quantum biochemistry approach.

Autoimmune inflammatory diseases, such as rheumatoid arthritis (RA) and ulcerative colitis, are associated with an uncontrolled production of cytokines leading to the pronounced inflammatory response of these disorders. Their therapy is currently focused on the inhibition of cytokine receptors, such as the Janus kinase (JAK) protein family. Tofacitinib and peficitinib are JAK inhibitors that have been recently approved to treat rheumatoid arthritis. In this study, an in-depth analysis was carried out through quantum biochemistry to understand the interactions involved in the complexes formed by JAK1 and tofacitinib or peficitinib. Computational analyses provided new insights into the binding mechanisms between tofacitinib or peficitinib and JAK1. The essential amino acid residues that support the complex are also identified and reported. Additionally, we report new interactions, such as van der Waals; hydrogen bonds; and alkyl, pi-alkyl, and pi-sulfur forces, that stabilize the complexes. The computational results revealed that peficitinib presents a similar affinity to JAK1 compared to tofacitinib based on their interaction energies.