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Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder associated with insulin resistance (IR) and hyperandrogenaemia (HA). Metabolic inflammation (MI), characterized by a chronic low-grade inflammatory state, is intimately linked with chronic metabolic diseases such as IR and diabetes and is also considered an essential factor in the development of PCOS. Insulin-like growth factor 1 (IGF-1) plays an essential role in PCOS pathogenesis through its multiple functions in regulating cell proliferation metabolic processes and reducing inflammatory responses. This review summarizes the molecular mechanisms by which IGF-1, via MI, participates in the onset and progression of PCOS, aiming to provide insights for studies and clinical treatment of PCOS., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The inflammasome has an essential function in innate immune, responding to a wide variety of stimuli. Here we show that the lncRNA Neat1 promotes the activation of several inflammasomes. Neat1 associates with the NLRP3, NLRC4, and AIM2 inflammasomes in mouse macrophages to enhance their assembly and subsequent pro-caspase-1 processing. Neat1 also stabilizes the mature caspase-1 to promote interleukin-1β production and pyroptosis. Upon stimulation with inflammasome-activating signals, Neat1, which normally resides in the paraspeckles, disassociates from these nuclear bodies and translocates to the cytoplasm to modulate inflammasome activation using above mechanism. Neat1 is also up-regulated under hypoxic conditions in a HIF-2α-dependent manner, mediating the effect of hypoxia on inflammasomes. Moreover, in the mouse models of peritonitis and pneumonia, Neat1 deficiency significantly reduces inflammatory responses. These results reveal a previously unrecognized role of lncRNAs in innate immunity, and suggest that Neat1 is a common mediator for inflammasome stimuli.

Keratitis is a worldwide sight-threatening disease. Current drugs generate various adverse effects. Large molecules hardly penetrate ocular tissues. Small peptides derived from endogenous protein display certain advantages. Previously we indentified a novel peptide (PAPep) from human pancreatitis-associated protein (PAP), a protein with protective effect against inflammatory diseases. To further examine the effect of PAPep on inflammatory disease and expand its scope of potential clinical application, especially in keratitis, we tested the effect of PAPep on various aspects of lipopolysaccharide (LPS)--induced corneal inflammation in vivo and in vitro. Dexamethasone (DXM) was used as a drug control. Our results suggested that PAPep suppressed the clinical manifestation, histological disorder and inflammatory cells infiltration and reduced the release of interleukin (IL)-6, IL-8 and monocyte chemotactic protein (MCP)-1 in the cornea. Moreover, PAPep inhibited LPS-induced mRNA and protein expression of the three cytokines in the corneal fibroblasts, prevented translocation of NF-κB and interrupted the phosphorylation of IKKα/β/IκBα/NF-κB. Our study demonstrates that PAPep could effectively attenuate LPS-induced keratitis, more likely by virtue of inhibiting the activation of the IKKα/β/IκBα/NF-κB pathway. PAPep may be considered to be a promising and safe drug for therapeutic application for ocular inflammation., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: Pancreatitis-associated protein (PAP) is a pancreatic secretory protein belongs to the group VII of C-type lectin family. Emerging evidence suggests that PAP plays a protective effect in inflammatory diseases. In the present study, we newly identified a 16-amino-acid peptide (named PAPep) derived from C-type lectin-like domain (CTLD) of human PAP with potent anti-inflammatory activity using both in vivo and in vitro assays., Methodology/principal Findings: We assessed the anti-inflammatory effect of PAPep on endotoxin-induced uveitis (EIU) in rats and demonstrated that intravitreal pretreatment of PAPep concentration-dependently attenuated clinical manifestation of EIU rats, reduced protein leakage and cell infiltration into the aqueous humor (AqH), suppressed tumor necrosis factor (TNF)-α, interleukin (IL)-6, intercellular adhesion molecule-1 (ICAM-1) and monocyte chemoattractant protein (MCP)-1 production in ocular tissues, and improved histopathologic manifestation of EIU. Furthermore, PAPep suppressed the LPS-induced mRNA expression of TNF-α and IL-6 in RAW 264.7 cells, inhibited protein expression of ICAM-1 in TNF-α-stimulated human umbilical vein endothelial cells (HUVECs) as well as U937 cells adhesion to HUVECs. Western blot analysis in ocular tissues and different cell lines revealed that the possible mechanism for this anti-inflammatory effect of PAPep may depend on its ability to inhibit the activation of NF-kB signaling pathway., Conclusions/significance: Our studies provide the first evidence that the sequence of PAPep is within the critically active region for the anti-inflammatory function of PAP and the peptide may be a promising candidate for the management of ocular inflammatory diseases.

Objective: To study the anti-inflammatory mechanism of total saponins from Semen Nigellae (TSSN)., Method: IFN-gamma plus LPS stimulated RAW 264. 7 macrophage has been used as inflammatory experimental model. Griess reaction for nitric oxide production, FRAP assay for total antioxidant capacity, RT-PCR for mRNA expression and Western blot for protein expression examination were performed., Result: TSSN inhibited NO production in a dose-dependent manner. The gene and protein expression of iNOS were also suppressed by the herb extract. TSSN treatment significantly attenuated mRNA of inflammatory mediators such as COX-2, IL-1beta, IL-6 while increased PPAR-gamma gene and protein expression. Furthermore, phosphorylation of ERK (p-ERK) was markedly inhibited by TSSN., Conclusion: TSSN suppressed pro-inflammatory mediators such as COX-2, IL-1beta, IL-6 and increased anti-inflammatory mediator PPAR-gamma expression. Meanwhile, TSSN inhibited over production of NO and iNOS expression through ERK/MAPK pathway.

Proteolytic activation of initiator procaspases is a crucial step in the cellular commitment to apoptosis. Alternative models have been postulated for the activation mechanism, namely the oligomerization or induced proximity model and the allosteric regulation model. While the former holds that procaspases become activated upon proper oligomerization by an adaptor protein, the latter states that the adaptor is an allosteric regulator for procaspases. The allosteric regulation model has been applied for the activation of procaspase-9 by apoptotic protease-activating factor (Apaf-1) in an oligomeric complex known as the apoptosome. Using approaches that allow for controlled oligomerization, we show here that aggregation of multiple procaspase-9 molecules can induce their activation independent of the apoptosome. Oligomerization-induced procaspase-9 activation, both within the apoptosome and in artificial systems, requires stable homophilic association of the protease domains, raising the possibility that the function of Apaf-1 is not only to oligomerize procaspase-9 but also to maintain the interaction of the caspase-9 protease domain after processing. In addition, we provide biochemical evidence that other apoptosis initiator caspases (caspase-2 and -10) as well as a procaspase involved in inflammation (murine caspase-11) are also activated by oligomerization. Thus, oligomerization of precursor molecules appears to be a general mechanism for the activation of both apoptosis initiator and inflammatory procaspases.

Highlights: [•] miR-93 is downregulated in the eyes of LPS-induced EIU rats. [•] miR-93 is downregulated in LPS-treated RAW 264.7 cells. [•] miR-93 inhibits LPS-induced inflammatory cytokine production. [•] miR-93 inhibits LPS-induced activation of NF-κB signaling through IRAK4. [Copyright &y& Elsevier]

Abstract: Thrombomodulin (TM) is a single-transmembrane glycoprotein receptor for thrombin, which is best known as a cofactor for thrombin-mediated activation of anticoagulant protein C. C-type lectin-like domain (CTLD) of TM has distinct coagulation/fibrinolysis-independent anti-inflammatory properties. Here we found anti-inflammatory effects of a novel peptide (GC31) from CTLD of TM in endotoxin-induced uveitis, which was characterized by a reduction of leukocyte counts, protein concentration, tumor necrosis factor (TNF)-α and monocyte chemoattractant protein (MCP)-1 levels in aqueous humor. Through in vitro experiments, we further found that GC31 suppressed TNF-α and interleukin (IL)-6 expressions in lipopolysaccharide (LPS)-stimulated macrophage-like RAW264.7 cells and interrupted LPS-induced nuclear factor-κB (NF-κB) activation. These data indicate a beneficial role of peptide GC31 in preventing intraocular inflammatory response, especially uveitis. [Copyright &y& Elsevier]