cPLA2α Enzyme Inhibition Attenuates Inflammation and Keratinocyte Proliferation

As a regulator of cellular inflammation and proliferation, cytosolic phospholipase A2 α (cPLA2α) is a promising therapeutic target for psoriasis; indeed, the cPLA2α inhibitor AVX001 has shown efficacy against plaque psoriasis in a phase I/IIa clinical trial. To improve our understanding of the anti-psoriatic properties of AVX001, we sought to determine how the compound modulates inflammation and keratinocyte hyperproliferation, key characteristics of the psoriatic epidermis. We measured eicosanoid release from human peripheral blood mononuclear cells (PBMC) and immortalized keratinocytes (HaCaT) and studied proliferation in HaCaT grown as monolayers and stratified cultures. We demonstrated that inhibition of cPLA2α using AVX001 produced a balanced reduction of prostaglandins and leukotrienes; significantly limited prostaglandin E2 (PGE2) release from both PBMC and HaCaT in response to pro-inflammatory stimuli; attenuated growth factor-induced arachidonic acid and PGE2 release from HaCaT; and inhibited keratinocyte proliferation in the absence and presence of exogenous growth factors, as well as in stratified cultures. These data suggest that the anti-psoriatic properties of AVX001 could result from a combination of anti-inflammatory and anti-proliferative effects, probably due to reduced local eicosanoid availability.

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miR-19a and miR-20a and Tissue Factor Expression in Activated Human Peripheral Blood Mononuclear Cells

Thrombosis ◽

10.1155/2017/1076397 ◽

2017 ◽

Vol 2017 ◽

pp. 1-6 ◽

Cited By ~ 3

Author(s):

Cristina Balia ◽

Mirella Giordano ◽

Valentina Scalise ◽

Tommaso Neri ◽

Gabriella Fontanini ◽

...

Keyword(s):

Angiotensin Ii ◽

Peripheral Blood Mononuclear Cells ◽

High Glucose ◽

Peripheral Blood ◽

Mononuclear Cells ◽

Human Peripheral Blood ◽

Peripheral Blood Mononuclear ◽

Blood Mononuclear Cells ◽

Inflammatory Stimuli

Background and Aims. To investigate the behaviour of miR-19a and miR-20a, two microRNAs involved in posttranscriptional modulation of TF expression in peripheral blood mononuclear cells (PBMCs) exposed to high glucose (HG) and lipopolysaccharide (LPS), and to evaluate the involvement of angiotensin II in that process. Methods. TF Procoagulant Activity (PCA, one-stage clotting assay), antigen (Ag, ELISA), and miR-19a and miR-20a levels (specific TaqMan® MicroRNA Assays) were evaluated in PBMCs exposed to high glucose (HG, 50 mM), LPS (100 ng/mL), and Olmesartan (OLM, 10−6 M), an angiotensin II type 1 receptor antagonist. Results. HG increased TF expression and decreased both miRs as compared to control glucose conditions (11.1 mM). In HG-activated PBMCs, LPS stimulated TF expression and downregulated miR-20a, an effect reverted by OLM (10−6 M); miR-19a expression was unchanged by LPS in both CG and HG conditions. Conclusions. miR-19a and miR-20a are inhibited by inflammatory stimuli active on TF expression and their response differs by the stimulus under investigation; angiotensin II may participate in that mechanism.

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Mesenchymal Stromal Cell Bioreactor for Ex Vivo Reprogramming of Human Immune Cells

Scientific Reports ◽

10.1038/s41598-020-67039-w ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Ashley Allen ◽

Natalie Vaninov ◽

Matthew Li ◽

Sunny Nguyen ◽

Maneet Singh ◽

...

Keyword(s):

Immune Cells ◽

Mononuclear Cells ◽

Ex Vivo ◽

Human Peripheral Blood ◽

Perfusion Culture ◽

Bioreactor Culture ◽

Peripheral Blood Mononuclear ◽

Inflammatory Stimuli ◽

Human Immune ◽

And Function

Abstract Bone marrow mesenchymal stromal cells (MSCs) have been studied for decades as potent immunomodulators. Clinically, they have shown some promise but with limited success. Here, we report the ability of a scalable hollow fiber bioreactor to effectively maintain ideal MSC function as a single population while also being able to impart an immunoregulatory effect when cultured in tandem with an inflamed lymphocyte population. MSCs were seeded on the extraluminal side of hollow fibers within a bioreactor where they indirectly interact with immune cells flowing within the lumen of the fibers. MSCs showed a stable and predictable metabolite and secreted factor profile during several days of perfusion culture. Exposure of bioreactor-seeded MSCs to inflammatory stimuli reproducibly switched MSC secreted factor profiles and altered microvesicle composition. Furthermore, circulating, activated human peripheral blood mononuclear cells (PBMCs) were suppressed by MSC bioreactor culture confirmed by a durable change in their immunophenotype and function. This platform was useful to study a model of immobilized MSCs and circulating immune cells and showed that monocytes play an important role in MSC driven immunomodulation. This coculture technology can have broad implications for use in studying MSC-immune interactions under flow conditions as well as in the generation of ex vivo derived immune cellular therapeutics.

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Identification of Salicylates in Willow Bark (Salix Cortex) for Targeting Peripheral Inflammation

International Journal of Molecular Sciences ◽

10.3390/ijms222011138 ◽

2021 ◽

Vol 22 (20) ◽

pp. 11138

Author(s):

Kyriaki Antoniadou ◽

Corinna Herz ◽

Nguyen Phan Khoi Le ◽

Verena Karolin Mittermeier-Kleßinger ◽

Nadja Förster ◽

...

Keyword(s):

Mononuclear Cells ◽

Clinical Medicine ◽

Human Peripheral Blood ◽

2D Nmr ◽

Cd Spectroscopy ◽

Pharmacological Interventions ◽

Peripheral Blood Mononuclear ◽

Pge2 Release ◽

Willow Bark ◽

Nmr Techniques

Salix cortex-containing medicine is used against pain conditions, fever, headaches, and inflammation, which are partly mediated via arachidonic acid-derived prostaglandins (PGs). We used an activity-guided fractionation strategy, followed by structure elucidation experiments using LC-MS/MS, CD-spectroscopy, and 1D/2D NMR techniques, to identify the compounds relevant for the inhibition of PGE2 release from activated human peripheral blood mononuclear cells. Subsequent compound purification by means of preparative and semipreparative HPLC revealed 2′-O-acetylsalicortin (1), 3′-O-acetylsalicortin (2), 2′-O-acetylsalicin (3), 2′,6′-O-diacetylsalicortin (4), lasiandrin (5), tremulacin (6), and cinnamrutinose A (7). In contrast to 3 and 7, compounds 1, 2, 4, 5, and 6 showed inhibitory activity against PGE2 release with different potencies. Polyphenols were not relevant for the bioactivity of the Salix extract but salicylates, which degrade to, e.g., catechol, salicylic acid, salicin, and/or 1-hydroxy-6-oxo-2-cycohexenecarboxylate. Inflammation presents an important therapeutic target for pharmacological interventions; thus, the identification of relevant key drugs in Salix could provide new prospects for the improvement and standardization of existing clinical medicine.

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