Publications by authors named "Sadiq Umar"

Mesenchymal stem cell derived extracellular vesicles (MSC EVs) are paracrine modulators of macrophage function. Scientific research has primarily focused on the immunomodulatory and regenerative properties MSC EVs derived from bone marrow. The dental pulp is also a source for MSCs, and their anatomical location and evolutionary function has primed them to be potent immunomodulators.

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Aim: Sepsis is a life-threatening clinical syndrome comprising multiorgan dysfunctions caused by a disproportionate body immune response. There are several animal sepsis models which are based on cecum ligation, cecal puncture, and cecum slurry injection. The major limitation of all current sepsis models is the high variability owing to the variable degree of ligation, puncture and inconsistent microbial composition used for sepsis initiation.

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Objectives: Syntenin-1, a novel endogenous ligand, was discovered to be enriched in rheumatoid arthritis (RA) specimens compared with osteoarthritis synovial fluid and normal synovial tissue (ST). However, the cellular origin, immunoregulation and molecular mechanism of syntenin-1 are undescribed in RA.

Methods: RA patient myeloid and lymphoid cells, as well as preclinical models, were used to investigate the impact of syntenin-1/syndecan-1 on the inflammatory and metabolic landscape.

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O-GlcNAcylation is a reversible post-translational modification that regulates numerous cellular processes, including embryonic development as well as immune responses. However, its role in inflammation remains ambiguous. This study was designed to examine the role of O-GlcNAcylation in rheumatoid arthritis (RA) and its regulation using human RA patient-derived synovial fibroblasts (RASFs).

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Escalated innate immunity plays a critical role in SARS-CoV-2 pathology; however, the molecular mechanism is incompletely understood. Thus, we aim to characterize the molecular mechanism by which SARS-CoV-2 Spike protein advances human macrophage (Mϴ) inflammatory and glycolytic phenotypes and uncover novel therapeutic strategies. We found that human Mϴs exposed to Spike protein activate IRAK4 phosphorylation.

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This study was designed to delineate the functional significance of CCL21 in metabolic reprogramming in experimental arthritis and differentiated rheumatoid arthritis (RA) macrophages (MΦs). To characterize the influence of CCL21 on immunometabolism, its mechanism of action was elucidated by dysregulating glucose uptake in preclinical arthritis and RA MΦs. In CCL21 arthritic joints, the glycolytic intermediates hypoxia-inducible factor 1α (HIF1α), cMYC and GLUT1 were overexpressed compared with oxidative regulators estrogen-related receptor γ and peroxisome proliferator-activated receptor gamma coactivator 1 (PGC1)-α.

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Recent studies show a connection between glycolysis and inflammatory response in rheumatoid arthritis (RA) macrophages (MΦs) and fibroblasts (FLS). Yet, it is unclear which pathways could be targeted to rebalance RA MΦs and FLS metabolic reprogramming. To identify novel targets that could normalize RA metabolic reprogramming, TLR7-mediated immunometabolism was characterized in RA MΦs, FLS and experimental arthritis.

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Recent studies have shown the significance of metabolic reprogramming in immune and stromal cell function. Yet, the metabolic reconfiguration of RA macrophages (MΦs) is incompletely understood during active disease and in crosstalk with other cell types in experimental arthritis. This study elucidates a distinct regulation of glycolysis and oxidative phosphorylation in RA MΦs compared to fibroblast (FLS), although PPP (Pentose Phosphate pathway) is similarly reconfigured in both cell types.

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The molecular mechanism of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Spike protein was characterized to identify novel therapies. The impact of tofacitinib, IL-6R Ab, or TNFi therapy was determined on Spike protein or LPS/IFN-γ-induced signaling, inflammation, and metabolic reprogramming in MΦs and/or rheumatoid arthritis (RA) fibroblast-like synoviocyte (FLS). ACE2 frequency was markedly expanded in MΦs compared to T cells and RA FLS.

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Objective: In rheumatoid arthritis (RA), elevated serum interleukin-34 (IL-34) levels are linked with increased disease severity. IL-34 binds to 2 receptors, macrophage colony-stimulating factor receptor (M-CSFR) and syndecan 1, which are coexpressed in RA macrophages. Expression of both IL-34 and syndecan 1 is strikingly elevated in the RA synovium, yet their mechanisms of action remain undefined.

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This study elucidates the mechanism of CCL25 and CCR9 in rheumatoid arthritis (RA). RA synovial fluid (SF) expresses elevated levels of CCL25 compared to OA SF and plasma from RA and normal. CCL25 was released into RA SF by fibroblasts (FLS) and macrophages (MΦs) stimulated with IL-1β and IL-6.

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Thirty percent of psoriasis patients develop psoriatic arthritis (PsA), nevertheless the mechanism remains unknown. Endogenous GU-rich miRNAs activate endosomal TLR7 that plays a critical role in autoimmune diseases. We found that endogenous TLR7 ligands, miR-29 and miR-Let7b, were markedly increased in PsA compared to osteoarthritis (OA) synovial fluid (SF)s.

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Innate and adaptive immunity regulate the inflammatory and erosive phenotypes observed in rheumatoid arthritis (RA) patients. Hence, identifying novel pathways that participate in different stages of RA pathology will provide valuable insights concerning the mechanistic behavior of different joint leukocytes and the strategy to restrain their activity. Recent findings have revealed that CCL21 poses as a risk factor for RA and expression of its receptor, CCR7, on circulating monocytes is representative of the patient's disease activity score.

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Rheumatoid arthritis (RA) is an autoimmune disorder, in which imbalance in synthesis and production of inflammatory cytokines promotes cartilage and bone destruction. Out of the numerous factors contributing to RA prognosis, the transcription factor NF-kBp65 and p38 mitogen-activated protein kinase (p38MAPK) signaling module has been well implicated as a key regulator of inflammation and downstream signaling events in RA. Stigmasterol (STG) is a natural plant based product exhibiting anti-inflammatory activity, however, the mechanism through which it exhibits anti-inflammatory activity has not been completely understood.

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Flares of joint inflammation and resistance to currently available biologic therapeutics in rheumatoid arthritis (RA) patients could reflect activation of innate immune mechanisms. Herein, we show that a TLR7 GU-rich endogenous ligand, miR-Let7b, potentiates synovitis by amplifying RA monocyte and fibroblast (FLS) trafficking. miR-Let7b ligation to TLR7 in macrophages (MΦs) and FLSs expanded the synovial inflammatory response.

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Background: Chemokines are a family of low molecular weight proteins that induce chemotaxis of inflammatory cells, which mainly depends on the recognition of a chemo-attractant gradient and interaction with the substratum. In Rheumatoid Arthritis (RA), abundant chemokines are expressed in synovial tissue, cause inflammatory cells migration into the inflamed joint that necessitates the formation of new blood vessels i.e.

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Objective: To prepare a novel nanoemulsion- Carbopol® 934 gel for Eugenol, in order to prevent the periodontitis.

Material And Methods: Spontaneous emulsification method was used for the preparation of nanoemulsion in which it contain Eugenol (oil phase), Tween-80 (surfactant), and PEG (co-surfactant). To the development of best nanoemulsion, three-factor three-level central composite design was used in which %oil; %S and % water were optimized as independent variables.

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In rheumatoid arthritis (RA), synovial tissue abundantly expresses CCL21, a chemokine strongly associated with RA susceptibility. In this study, we aimed to characterize the functional significance of CCL21/CCR7 signaling in different phases of RA pathogenesis. We determined that CCR7 is a hallmark of RA M1 synovial fluid (SF) macrophages, and its expression in RA monocytes and in vitro differentiated macrophages is closely associated with disease activity score (DAS28).

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Synovial macrophages are crucial in the development of joint inflammation and bone damage; however, the pathways that control macrophage remodeling in inflammatory M1 cells or bone-eroding osteoclasts are not fully understood. We determined that elevated IL-7R/CD127 expression is the hallmark of rheumatoid arthritis (RA) M1 macrophages and that these cells are highly responsive to interleukin-7 (IL-7)-driven osteoclastogenesis. We established that lipopolysaccharide (LPS), interferon-γ (IFNγ), and tumor necrosis factor-α (TNFα), the classic M1 macrophage mediators, enhance IL-7R expression in RA and murine macrophages.

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Background: Nomadic populations have a considerably higher risk of contracting a number of diseases but, despite the magnitude of the public health risks involved, they are mostly underserved with few health policies or plans to target them. Nomadic population movements are shown to be a niche for the transmission of diseases, including poliomyelitis. The nomadic routes traverse the northern states of Nigeria to other countries in the Lake Chad subregion.

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Background: In resource-scarce settings like Nigeria, access to conventional drugs and antiretroviral therapy (ART) is highly limited, hence the resort to use of traditional herbal medicine by a significant number of people living with human immunodeficiency virus and acquired immunodeficiency syndrome (HIV/AIDS) (PLWHAs). Traditional medicine (TM) continues to provide health coverage for most of the people in developing countries, and it is equally becoming increasingly popular in western countries.

Aim: This study aims to present the status and use of TM and determine the factors associated with its use among patients with HIV/AIDS on highly active ART in a tertiary health institution in Sokoto, Northwest Nigeria.

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Obesity can instigate and sustain a systemic low-grade inflammatory environment that can amplify autoimmune disorders and their associated comorbidities. Metabolic changes and inflammatory factors produced by the adipose tissue have been reported to aggravate autoimmunity and predispose the patient to cardiovascular disease (CVD) and metabolic comorbidities. Rheumatoid arthritis (RA) and psoriatic arthritis (PsA) are autoimmune arthritic diseases, often linked with altered body mass index (BMI).

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