Porphyromonas gingivalis Gingipains Induce Cyclooxygenase-2 Expression and Prostaglandin E2 Production via ERK1/2-Activated AP-1 (c-Jun/c-Fos) and IKK/NF-κB p65 Cascades.

Porphyromonas gingivalis is commonly known as one of the major pathogens contributing to periodontitis, and its persistent infection may increase the risk for the disease. The proinflammatory mediators, including IL-6, TNF-α, and cyclooxygenase-2 (COX-2)/PGE2, are closely associated with progression of periodontitis. In this study, we focused on the cysteine protease "gingipains," lysine-specific gingipain, arginine-specific gingipain (Rgp) A, and RgpB, produced by P. gingivalis, and used the wild-type strain and several gene-deletion mutants (rgpA, rgpB, kgp, and fimA) to elucidate the involvement of gingipains in COX-2 expression and PGE2 production. We infected human monocytes, which are THP-1 cells and primary monocytes, with these bacterial strains and found that gingipains were involved in induction of COX-2 expression and PGE2 production. We have shown that the protease activity of gingipains was crucial for these events by using gingipain inhibitors. Furthermore, activation of ERK1/2 and IκB kinase was required for gingipain-induced COX-2 expression/PGE2 production, and these kinases activated two transcription factors, c-Jun/c-Fos (AP-1) and NF-κB p65, respectively. In particular, these data suggest that gingipain-induced c-Fos expression via ERK is essential for AP-1 formation with c-Jun, and activation of AP-1 and NF-κB p65 plays a central role in COX-2 expression/PGE2 production. Thus, we show the (to our knowledge) novel finding that gingipains with the protease activity from P. gingivalis induce COX-2 expression and PGE2 production via activation of MEK/ERK/AP-1 and IκB kinase/NF-κB p65 in human monocytes. Hence it is likely that gingipains closely contribute to the inflammation of periodontal tissues.

Prostaglandin E2 increases the expression of cyclooxygenase-2 in cultured rat microglia.

Prostaglandin E2 (PGE2) plays pivotal roles in controlling microglial activation with the EP2 receptor, a PGE2 receptor subtype. Activated microglia are often reported to increase cyclooxygenase (COX)-2 expression, followed by PGE2 production, but it is unclear whether extracellular PGE2 is involved in microglial PGE2 synthesis. In the present study, we report that PGE2 increases COX-2 protein in microglia. In a culture system, PGE2 at 10-6 M for 3 h increased COX-2 and microsomal PGE synthase (mPGES)-1 mRNA levels, and reduced mPGES-2, but did not affect COX-1 or cytosolic PGE synthase (cPGES) in microglia. PGE2 at 10-6 M for 3 h also increased the COX-2 protein level, but did not affect COX-1, mPGES-1, mPGES-2, or cPGES. An EP2 agonist, ONO-AE1-259-01, also increased COX-2 and mPGES-1 mRNA levels, and reduced mPGES-2, but did not affect COX-1 or cPGES, whereas an EP1 agonist, ONO-DI-004, an EP3 agonist, ONO-AE-248, and an EP4 agonist, ONO-AE1-329, had no effect. Similar to PGE2, ONO-AE1-259-01 increased the COX-2 protein level, but did not affect COX-1, mPGES-1, mPGES-2, or cPGES. In addition, the effects of PGE2 were inhibited by an EP2 antagonist, PF-04418948, but not by an EP1 antagonist, ONO-8713, an EP3 antagonist, ONO-AE3-240, or an EP4 antagonist, ONO-AE3-208, at 10-6 M. On the other hand, lipopolysaccharide (LPS) increased PGE2 production, but the LPS-induced PGE2 production was not affected by ONO-8713, PF-04418948, ONO-AE3-240, or ONO-AE3-208. These results indicate that PGE2 increases COX-2 protein in microglia through the EP2 receptor supporting the idea that extracellular PGE2 has a triggering aspect for microglial activation.

4-Octyl-Itaconate and Dimethyl Fumarate Inhibit COX2 Expression and Prostaglandin Production in Macrophages.

PGs are important proinflammatory lipid mediators, the significance of which is highlighted by the widespread and efficacious use of nonsteroidal anti-inflammatory drugs in the treatment of inflammation. 4-Octyl itaconate (4-OI), a derivative of the Krebs cycle-derived metabolite itaconate, has recently garnered much interest as an anti-inflammatory agent. In this article, we show that 4-OI limits PG production in murine macrophages stimulated with the TLR1/2 ligand Pam3CSK4. This decrease in PG secretion is due to a robust suppression of cyclooxygenase 2 (COX2) expression by 4-OI, with both mRNA and protein levels decreased. Dimethyl fumarate, a fumarate derivative used in the treatment of multiple sclerosis, with properties similar to itaconate, replicated the phenotype observed with 4-OI. We also demonstrate that the decrease in COX2 expression and inhibition of downstream PG production occurs in an NRF2-independent manner. Our findings provide a new insight into the potential of 4-OI as an anti-inflammatory agent and also identifies a novel anti-inflammatory function of dimethyl fumarate.

Upregulation of the mGlu5 receptor and COX-2 protein in the mouse brain after imipramine and NS398, searching for mechanisms of regulation.

Imipramine belongs to a group of tricyclic antidepressants (TCAs). It has been also documented that its antidepressant activity connects with the modulation of cytosolic phospholipase A2 (cPLA2) and arachidonic acid (AA) turnover. Through this mechanism, imipramine can indirectly modify glutamate (Glu) transmission. Additionally, it has been shown that chronic treatment with imipramine results in the upregulation of the metabotropic glutamate receptor subtype 5 (mGlu5 receptor) in the hippocampus of rats. Our previous study revealed that manipulation of the AA pathway via inhibition of cyclooxygenase-2 (COX-2) by selective COX-2 inhibitor (NS398) could effectively modulate the behavior of mice treated with imipramine. Here, we hypothesized that COX-2 inhibition could similarly to imipramine influence mGlu5 receptor, and thus NS398 can modulate the effect of imipramine on Glu. Moreover, such regulation changes should correspond with alterations in neurotransmission. Increased cPLA activity after imipramine administration may change the activity of the AA pathway and the endocannabinoid metabolism, e.g., 2-Arachidonyl-glycerol (2-AG). To verify the idea, mGlu5 receptor level was investigated in the hippocampus (HC) and prefrontal cortex (PFC) of mice treated for 7 or 14 days with imipramine and/or COX-2 inhibitor: NS398. Western blot and PCR analyses were conducted. Moreover, the excitatory (Glu) and inhibitory (gamma-aminobutyric acid; GABA) neurotransmitters were measured using HPLC and 2-AG using ELISA. A time-dependent change in mGlu5 receptor and COX-2 protein level, COX-2 expression, and 2-AG level in the PFC after imipramine administration was found. Up-regulation of mGlu5 receptor after NS398 was found in HC and PFC. A structure-dependent shift between excitatory vs. inhibitory transmission was detected when NS398 and imipramine were co-administered.

Dihydrotestosterone regulation of cyclooxygenase-2 expression in bovine endometrial epithelium cells by androgen receptor mediated EGFR/PI3K/Akt pathway.

Uterine prostaglandins F2α (PGF2α) is essential for implantation, initiation of luteolysis and delivery. Previous studies have demonstrated that the expression of Cyclooxygenase-2 (COX-2), an enzyme limiting PGF2α rate, is regulated by steroid hormones, and also dihydrotestosterone (DHT) may be involved in regulating COX-2 expression both positively and negatively. However, it remains unclear how whether DHT regulates COX-2 expression and consequent PGF2α release in bovine endometrial epithelial cells (EECs). In this study, we evaluated the localization of the two isoforms of DHT synthetase 5α-reductase (5α-red1 and 5α-red2) and androgen receptor (AR) in bovine endometria by immunohistochemistry, and investigated 5α-red1, 5α-red2, AR, and DHT levels at the different stages of endometria (follicle, early-, mid-, and late-pregnancy phases). The results showed that 5α-red1, 5α-red2 and AR all were expressed in endometria, and their expressions and the level of DHT significantly increased in the late-pregnancy phase compared with the mid-pregnancy phase. Moreover, we cultured EECs from the mid-pregnancy phase and the in vitro study showed that DHT dose-dependently increased COX-2 expression and PGF2a release, but AR antagonist (flutamide) inhibited the stimulating effect via DHT. In addition, the DHT-induced COX-2 expression and PGF2α release were subjected to the regulation of both EGFR/PI3K/Akt/NFkB signaling as the inhibitors of EGFR (AG1478) and PI3K/Akt (LY294002) and NFkB (QNZ) attenuated the DHT mediated effect. Taken together, the results demonstrated that DHT-induced COX-2 expression and consequent PGF2α release in bovine EECs were mediated through AR-derived EGFR transactivation and PI3K/Akt cascade leading to NFkB activation.

Toll-like receptor-4 null mutation causes fetal loss and fetal growth restriction associated with impaired maternal immune tolerance in mice.

Maternal immune adaptation to accommodate pregnancy depends on sufficient availability of regulatory T (Treg) cells to enable embryo implantation. Toll-like receptor 4 is implicated as a key upstream driver of a controlled inflammatory response, elicited by signals in male partner seminal fluid, to initiate expansion of the maternal Treg cell pool after mating. Here, we report that mice with null mutation in Tlr4 (Tlr4-/-) exhibit impaired reproductive outcomes after allogeneic mating, with reduced pregnancy rate, elevated mid-gestation fetal loss, and fetal growth restriction, compared to Tlr4+/+ wild-type controls. To investigate the effects of TLR4 deficiency on early events of maternal immune adaptation, TLR4-regulated cytokines and immune regulatory microRNAs were measured in the uterus at 8 h post-mating by qPCR, and Treg cells in uterus-draining lymph nodes were evaluated by flow cytometry on day 3.5 post-coitum. Ptgs2 encoding prostaglandin-endoperoxide synthase 2, cytokines Csf2, Il6, Lif, and Tnf, chemokines Ccl2, Cxcl1, Cxcl2, and Cxcl10, and microRNAs miR-155, miR-146a, and miR-223 were induced by mating in wild-type mice, but not, or to a lesser extent, in Tlr4-/- mice. CD4+ T cells were expanded after mating in Tlr4+/+ but not Tlr4-/- mice, with failure to expand peripheral CD25+FOXP3+ NRP1- or thymic CD25+FOXP3+ NRP1+ Treg cell populations, and fewer Treg cells expressed Ki67 proliferation marker and suppressive function marker CTLA4. We conclude that TLR4 is an essential mediator of the inflammation-like response in the pre-implantation uterus that induces generation of Treg cells to support robust pregnancy tolerance and ensure optimal fetal growth and survival.

Targeting ROS/NF-κB sigaling pathway by the seedless black Vitis vinifera polyphenols in CCl4-intoxicated kidney, lung, brain, and spleen in rats.

Carbon tetrachloride (CCl4) is an abundant environmental pollutant that can generate free radicals and induce oxidative stress in different human and animal organs like the kidney, lung, brain, and spleen, causing toxicity. The present study evaluated the alleviative mechanism of the isolated polyphenolic fraction from seedless (pulp and skin) black Vitis vinifera (VVPF) on systemic oxidative and necroinflammatory stress in CCl4-intoxicated rats. Here, we found that the administration of VVPF to CCl4-intoxicated rats for ten days was obviously ameliorated the CCl4-induced systemic elevation in ROS, NO and TBARS levels, as well as MPO activity. Also, it upregulated the cellular activities of the enzymatic (SOD, and GPx) and non-enzymatic (TAC and GSH) antioxidants. Furthermore, the gene expression of the ROS-related necroinflammatory mediators (NF-κB, iNOS, COX-2, and TNF-α) in the kidney, brain, and spleen, as well as IL-1ß, and IL-8 in the lung were greatly restored. The histopathological studies confirmed these biochemical results and showed a noticeable enhancing effect in the architecture of the studied organs after VVPF intake. Thus, this study indicated that VVPF had an alleviative effect on CCl4-induced necroinflammation and oxidative stress in rat kidney, lung, brain, and spleen via controlling the ROS/NF-κB pathway.

Protective Effect of Membrane-Free Stem Cells against Lipopolysaccharide and Interferon-Gamma-Stimulated Inflammatory Responses in RAW 264.7 Macrophages.

Recently, adipose-derived stem cells (ADSCs) are considered to be ideal for application in cell therapy or tissue regeneration, mainly due to their wide availability and easy access. In this study, we examined the anti-inflammatory effects of membrane-free stem cell extract (MFSC-Ex) derived from ADSCs against lipopolysaccharide (LPS)/interferon-gamma (IFN-γ) on RAW 264.7 macrophage cells. Exposure of RAW macrophages to LPS and IFN-γ stimuli induced high levels of nitric oxide (NO), cyclooxygenase-2 (COX-2), and prostaglandin E2 (PGE2) production. However, pretreatment with MFSC-Ex inhibited LPS/IFN-γ-induced these pro-inflammatory mediators. To clarify the molecular mechanisms underlying the anti-inflammatory property of MFSC-Ex, we analyzed nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) protein expressions by Western blotting. Our study showed that treatment of MFSC-Ex significantly down-regulated inducible nitric oxide synthase (iNOS) and COX-2 protein expressions. Furthermore, phosphorylation of extracellular signal-regulated kinase (ERK) and p38 was also blocked by treatment with MFSC-Ex, indicating that inhibitory effect of MFSC-Ex on MAPK signaling cascade may attribute to inactivation of NF-κB. From these findings, we suggest that MFSC-Ex exert anti-inflammatory activities, which suppressed LPS/IFN-γ-induced production of NO, COX-2 and PGE2 by regulation of NF-κB and MAPK signaling pathway in RAW 264.7 macrophages. In conclusion, MFSC-Ex might provide a new therapeutic opportunity to treatment of inflammatory-related diseases.

Exogenous Vitamins K Exert Anti-Inflammatory Effects Dissociated from Their Role as Substrates for Synthesis of Endogenous MK-4 in Murine Macrophages Cell Line.

Vitamins K exert a range of activities that extend far beyond coagulation and include anti-inflammatory effects, but the mechanisms involved in anti-inflammatory action remain unclear. In the present study, we showed that various forms of exogenous vitamins-K1, K3, K2 (MK-4, MK-5, MK-6 and MK-7)-regulated a wide scope of inflammatory pathways in murine macrophages in vitro, including NOS-2, COX-2, cytokines and MMPs. Moreover, we demonstrated for the first time that macrophages are able to synthesise endogenous MK-4 on their own. Vitamins with shorter isoprenoid chains-K1, K3 and MK-5-exhibited stronger anti-inflammatory potential than vitamins with longer isoprenoid chains (MK-6 and MK-7) and simultaneously were preferably used as a substrate for MK-4 endogenous production. Most interesting, atorvastatin pretreatment inhibited endogenous MK-4 production but had no impact on the anti-inflammatory activity of vitamins K. In summary, our results demonstrate that macrophages are able to synthesise endogenous MK-4 using exogenous vitamins K, and statin inhibits this process. However, the anti-inflammatory effect of exogenous vitamins K was independent of endogenous MK-4 synthesis.

Melatonin Ameliorates LPS-Induced Testicular Nitro-oxidative Stress (iNOS/TNFα) and Inflammation (NF-kB/COX-2) via Modulation of SIRT-1.

Lipopolysaccharide (LPS) - an endotoxin that is being extensively used in laboratory to mimic microbial infection that adversely affects male fertility. This study investigated the protective effects of melatonin on LPS-induced testicular nitro-oxidative stress, inflammation, and associated damages in the testes of male golden hamsters, Mesocricetus auratus. Hamsters were administered with melatonin and LPS for 7 days. Testes of LPS treated hamsters showed degenerative changes (appearance of vacuoles, exfoliation, and depletion of germ cells in the seminiferous tubules), adverse effects on spermatogenesis (sperm count and viability), and steroidogenesis (declined serum and testicular testosterone). Furthermore, LPS treatment decreased melatonin content, melatonin receptor (MT1), and antioxidant potential (catalase and SOD), and simultaneously increased nitro-oxidative stress (CRP, nitrate, TNFα). LPS upregulated NF-kB, COX-2, and iNOS expressions to increase testicular inflammatory load that resulted in the decrease of germ cell proliferation and survival, thus culminating into germ cell apoptosis as indicated by AO-EB staining and caspase-3 expression. Administration of melatonin with LPS showed improved testicular histoarchitecture, sperm parameters, and testosterone level. Melatonin increased testicular antioxidant status (SOD, catalase) to counteract the LPS-induced testicular ROS and thus reduced testicular nitro-oxidative stress. Furthermore, melatonin treatment upregulated testicular SIRT-1 expression to inhibit LPS-induced inflammatory proteins, i.e., NF-kB/COX-2/iNOS expression. The rescue effect of melatonin was further supported by increased germ cell survival (Bcl-2), proliferation (PCNA), and declined apoptosis (caspase-3). In conclusion, our result demonstrated that melatonin rescued testes from LPS-induced testicular nitro-oxidative stress, inflammation, and associated damages by upregulation of SIRT-1.

Phytochemical Profile and Anti-Inflammatory Activity of the Fraction from Artemisia lavandulaefolia.

Artemisia lavandulaefolia, a traditional herbal medicine, has been utilized as anti-inflammatory and analgesia agent in clinic. Bioassay-guided fractionation resulted in a fraction (ALDF) with anti-inflammatory effect obtained from A. lavandulaefolia. Its main constituents were analyzed and identified by UPLC-ESI-Q-TOF-MS technology. ALDF showed the strong inhibitory activity on the nitrogen oxide (NO) production in LPS-induced RAW 264.7 macrophages with an IC50 value of 1.64±0.41 µg/mL. Further results displayed that ALDF also significantly suppressed the secretion of key pro-inflammatory mediators, including tumor necrosis factor-α (TNF-α), prostaglandin E2 (PGE2 ) and interleukin-1ß (IL-1ß), and the increase of the inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression induced by LPS stimulation. Mechanism study indicated that ALDF was able to block NF-κB signaling pathway through inhibiting IκB and p65 phosphorylation, as well as NF-κB p65 nuclear translocation. Furthermore, in vivo results in mice revealed that treatments with ALDF evoked significant inhibition on ear edema induced by xylene and on the writhing responses induced by acetic acid. These results suggest that ALDF holds great potential in the prevention and treatment of inflammatory disorders.

Assessment of the anti-rheumatoid arthritis activity of Gastrodia elata (tian-ma) and Radix aconitic lateralis preparata (fu-zi) via network pharmacology and untargeted metabolomics analyses.

AIM: Gastrodia elata and Radix aconiti lateralis preparrata are respectively named as Tian-Ma and Fu-Zi (TF) in Chinese. We explored the active components against rheumatoid arthritis (RA) from an extensively used couplet of Chinese herbs, Gastrodia elata and Radix aconiti lateralis preparata (TF) via untargeted metabolomics and network pharmacological approaches. METHODS: Water extracts of TF were mixed at ratios 1:1, 3:2 and 2:3 (w/w). Ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) was then utilized as metabolomics screening. Human Metabolome (http://www.hmdb.ca/) and Lipidmaps (http://www.lipidmaps.org/) databases were used to annotate detected compounds. Further identification of vital genes and important pathways associated with the anti-RA properties of the TF preparations was done via network pharmacology, and verified by real-time quantitative polymerase chain reaction (RT-qPCR). RESULTS: Four key compounds involved in unsaturated fatty acid biosynthesis and isoflavonoid biosynthesis were identified through metabolomics analyses. Three key components of TF associated with anti-RA activity were linoleic acid, daidzein, and daidzin. Results of RT-qPCR revealed that all 3 tested TF couplets (1:1, 3:2, and 2:3) markedly suppressed the transcription of PTGS2. These results were consistent with our network pharmacological predictions. CONCLUSIONS: The anti-RA properties of Tian-Ma and Fu-Zi are associated with the inhibition of arachidonic acid metabolism pathway.

Aminocellulose-grafted-polycaprolactone coated gelatin nanoparticles alleviate inflammation in rheumatoid arthritis: A combinational therapeutic approach.

Rheumatoid arthritis (RA) is a chronic autoimmune disorder and serious cause of disability. Despite considerable advances in RA management, challenges like extensive drug metabolism and rapid clearance causes poor bioavailability. Core-shell nanocarriers for co-delivery of glycyrrhizic acid (GA) and budesonide against RA were developed. GA-loaded gelatin nanoparticles (NPs) were synthesized and coated with budesonide encapsulated aminocellulose-grafted polycaprolactone (PCL-AC). GA- and budesonide-loaded PCL-AC-gel NPs had diameter of 200-225 nm. Dual drug-loaded (DDL) NPs reduced joint swelling and erythema in rats while markedly ameliorating bone erosion evidenced by radiological analysis, suppressed collagen destruction, restored synovial tissue, bone and cartilage histoarchitecture with reduced inflammatory cells infiltration. NPs also reduced various inflammatory biomarkers such as TNF-α, IL-1ß, COX-2, iNOS. Results of this study suggest that dual NPs exerted superior therapeutic effects in RA compared to free drugs which may be attributed to slow and sustained drug release and NPs' ability to inhibit inflammatory mediators.

Expression of COX-2 and Nrf2/GPx3 in the anterior vaginal wall tissues of women with pelvic organ prolapse.

PURPOSE: To evaluate COX-2 and Nrf2/GPx3 expressions in the lamina propria of the anterior vaginal wall tissues of women with and without pelvic organ prolapse (POP). METHODS: Tissue samples of anterior vaginal wall were examined using HE staining, immuohistochemical staining and Western blot for the expressions of COX-2/PGE2, Nrf2/GPx3, MMP2, TIMP1, collagen I and collagen III (n = 35, per group). RESULTS: Compared with control group, collagen fibers of the anterior vaginal wall were disorganized and discontinuous. Expressions of Nrf2, GPx3, TIMP1, collagen I and collagen III were found significantly lower in POP group (P < 0.05); while, expressions of COX-2, PGE2, and MMP2 were found significantly higher in POP group (P < 0.05). Statistically significant correlations of COX-2 and Nrf2/GPx3 were showed (P < 0.01). CONCLUSION: We found that the interaction between inflammation and oxidative stress was closely related to the development of POP. This study demonstrates that COX-2 and Nrf2 pathways may be involved in pathogenesis of POP, as promising potential therapeutic targets and agents.

Filifactor alocis and Tumor Necrosis Factor-Alpha Stimulate Synthesis of Visfatin by Human Macrophages.

There is little known about the effect of the periodontopathogen Filifactor alocis on macrophages as key cells of the innate immune defense in the periodontium. Therefore, the aim of the present study was to investigate the effect of F. alocis and additionally of the pro-inflammatory cytokine tumor necrosis factor-alpha (TNFα) on visfatin and other pro-inflammatory and proteolytic molecules associated with periodontitis in human macrophages. The presence of macrophage markers CD14, CD86, CD68, and CD163 was examined in gingival biopsies from healthy individuals and periodontitis patients. Human macrophages were incubated with F. alocis and TNFα for up to 2 d. The effects of both stimulants on macrophages were determined by real-time PCR, ELISA, immunocytochemistry, and immunofluorescence. F. alocis was able to significantly stimulate the synthesis of visfatin by human macrophages using TLR2 and MAPK pathways. In addition to visfatin, F. alocis was also able to increase the synthesis of cyclooxygenase 2, TNFα, and matrix metalloproteinase 1. Like F. alocis, TNFα was also able to stimulate the production of these proinflammatory and proteolytic molecules. Our results highlight the pathogenetic role of F. alocis in periodontal diseases and also underline the involvement of visfatin in the aetiopathogenesis of periodontitis.

TRPV1, Targeted by miR-338-3p, Induces Neuropathic Pain by Interacting with NECAB2.

A variety of studies have proposed that transient receptor potential vanilloid 1 (TRPV1) is involved in the progression of multiple diseases, including neuropathic pain. Although increased expression of TRPV1 in chronic constriction injury was described earlier, the underlying regulatory mechanisms of TRPV1 in neuropathic pain remain largely unknown. In our study, we constructed a chronic constriction injury (CCI) rat model to deeply analyze the mechanisms underlying TRPV1. RT-qPCR-indicated TRPV1 mRNA and protein expression were extremely upregulated in CCI rat dorsal spinal cord tissues. Then, TRPV1 was corroborated to interact with N-terminal EF-hand Ca2+-binding protein 2 (NECAB2). The mRNA and protein levels of NECAB2 were increased in CCI tissues. Moreover, TRPV1 and NECAB2 together regulated nociceptive procession-associated protein metabotropic glutamate receptor 5 (mGluR5), phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2), and Ca2+ in isolated microglia of CCI rats. Moreover, TRPV1 upregulation apparently increased mechanical allodynia and thermal hyperalgesia as well as the expression of inflammation-associated genes (COX-2, TNF-α, and IL-6). In addition, downregulation of NECAB2 significantly decreased mechanical allodynia and thermal hyperalgesia as well as the expression of COX-2, TNF-α, and IL-6. Furthermore, TRPV1 was confirmed to be a downstream target of miR-338-3p. TRPV1 overexpression abolished the inhibitory effect by miR-338-3p elevation on neuropathic pain development. In summary, this study proved TRPV1, targeted by miR-338-3p, induced neuropathic pain by interacting with NECAB2, which provides a potential therapeutic target for neuropathic pain treatment.

Carvedilol prevents pancreatic ß-cell damage and the development of type 1 diabetes in mice by the inhibition of proinflammatory cytokines, NF-κB, COX-2, iNOS and oxidative stress.

Inflammation is one of the main mechanisms of pancreatic ß-cell damage and the development of type 1 diabetes (T1D). Carvedilol, a beta-adrenergic receptor blocker, has been demonstrated to have anti-inflammatory and antioxidant effects. The aim of this study was to investigate the protective effect of carvedilol against pancreatic ß-cell damage and the development of T1D in an experimental model. T1D was induced in mice by multiple low-dose streptozotocin (STZ) injections. Diabetic mice were treated with carvedilol (15 and 20 mg/kg/day, orally) for 14 days. Results showed that blood glucose levels, diabetes incidence, body weight loss and insulitis in the pancreatic tissue were significantly reduced in mice treated with carvedilol. Treatment of mice with carvedilol significantly increased the levels of antioxidants glutathione (GSH), superoxide dismutase (SOD), and catalase and decreased the levels of malondialdehyde (MDA), nitric oxide (NO) and myeloperoxidase (MPO) in the pancreatic tissue as compared with those in the STZ-induced diabetic mice. Carvedilol decreased the expression of nuclear factor kappa B (NF-κB), cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) as important modulators of inflammation and ß-cell damage in the pancreatic tissue. In addition, carvedilol significantly reduced the levels of proinflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6 IL-12, IL-17, interferon (IFN)-γ and chemokine MCP-1, while increased the anti-inflammatory cytokine IL-10 in the pancreatic tissue. In conclusion, these findings suggest that carvedilol is able to prevent pancreatic ß-cell damage and the development of T1D in mice by the inhibition of inflammatory and oxidative mediators.

Effect of Ergothioneine on 7-Ketocholesterol-Induced Endothelial Injury.

Ergothioneine (ET) is a naturally occurring antioxidant that is synthesized by non-yeast fungi and certain bacteria. ET is not synthesized by animals, including humans, but is avidly taken up from the diet, especially from mushrooms. In the current study, we elucidated the effect of ET on the hCMEC/D3 human brain endothelial cell line. Endothelial cells are exposed to high levels of the cholesterol oxidation product, 7-ketocholesterol (7KC), in patients with cardiovascular disease and diabetes, and this process is thought to mediate pathological inflammation. 7KC induces a dose-dependent loss of cell viability and an increase in apoptosis and necrosis in the endothelial cells. A relocalization of the tight junction proteins, zonula occludens-1 (ZO-1) and claudin-5, towards the nucleus of the cells was also observed. These effects were significantly attenuated by ET. In addition, 7KC induces marked increases in the mRNA expression of pro-inflammatory cytokines, IL-1ß IL-6, IL-8, TNF-α and cyclooxygenase-2 (COX2), as well as COX2 enzymatic activity, and these were significantly reduced by ET. Moreover, the cytoprotective and anti-inflammatory effects of ET were significantly reduced by co-incubation with an inhibitor of the ET transporter, OCTN1 (VHCL). This shows that ET needs to enter the endothelial cells to have a protective effect and is unlikely to act via extracellular neutralizing of 7KC. The protective effect on inflammation in brain endothelial cells suggests that ET might be useful as a nutraceutical for the prevention or management of neurovascular diseases, such as stroke and vascular dementia. Moreover, the ability of ET to cross the blood-brain barrier could point to its usefulness in combatting 7KC that is produced in the CNS during neuroinflammation, e.g. after excitotoxicity, in chronic neurodegenerative diseases, and possibly COVID-19-related neurologic complications.

Anti-inflammatory and Cytoprotective Effect of Clinacanthus nutans Leaf But Not Stem Extracts on 7-Ketocholesterol Induced Brain Endothelial Cell Injury.

Clinacanthus nutans (Lindau) (C. nutans) has diverse uses in traditional herbal medicine for treating skin rashes, insect and snake bites, lesions caused by herpes simplex virus, diabetes mellitus and gout in Singapore, Malaysia, Indonesia, Thailand and China. We previously showed that C. nutans has the ability to modulate the induction of cytosolic phospholipase A2 (cPLA2) expression in SH-SY5Y cells through the inhibition of histone deacetylases (HDACs). In the current study, we elucidated the effect of C. nutans on the hCMEC/D3 human brain endothelial cell line. Endothelial cells are exposed to high levels of the cholesterol oxidation product, 7-ketocholesterol (7KC), in patients with cardiovascular disease and diabetes, and this process is thought to mediate pathological inflammation. 7KC induced a dose-dependent loss of hCMEC/D3 cell viability, and such damage was significantly inhibited by C. nutans leaf extracts but not stem extracts. 7KC also induced a marked increase in mRNA expression of pro-inflammatory cytokines, IL-1ß IL-6, IL-8, TNF-α and cyclooxygenase-2 (COX-2) in brain endothelial cells, and these increases were significantly inhibited by C. nutans leaf but not stem extracts. HPLC analyses showed that leaf extracts have a markedly different chemical profile compared to stem extracts, which might explain their different effects in counteracting 7KC-induced inflammation. Further study is necessary to identify the putative phytochemicals in C. nutans leaves that have anti-inflammatory properties.

Evaluation of the oral administration of α-l-guluronic acid on COX-1 and COX-2 gene expression profile in ankylosing spondylitis patients.

Ankylosing spondylitis (AS) is a chronic autoimmune arthritis disease with a genetic background, affecting the skeletal axis, sacroiliac, and peripheral joints. Nonsteroidal anti-inflammatory drugs (NSAIDs) are the first-line treatment for AS to alleviate the inflammation and pain. Despite the beneficial effect, their use is accompanied by a wide variety of possible side effects in the gastrointestinal and kidneys. The α-l-guluronic acid (G2013) is a new nonsteroidal anti-inflammatory patented (PCT/EP2017/067920) drug, which has shown its anti-inflammatory properties in the previous investigations. The present study revealed the oral administration effect of G2013 on COX-1 and COX-2 gene expression in AS patients. The blood samples of twelve 18-45 years old patients suffering AS and BASDAI >4, and BASFI >4, before and after 12 weeks of treatment with G2013 and 12 blood samples of healthy volunteers were collected and the effect of G2013 on the gene expression of COX-1 and COX-2 enzymes were assessed by Real-Time PCR. The results indicate that G2013 is able to reduce the gene expression level of COX-1 and COX-2 enzymes in treated AS patients compared to healthy control. Statistically significant differences were not observed between the treatment and the healthy control groups. According to the findings, G2013 might be categorized and introduced as a novel NSAID for the treatment of AS.