Experimental Models Of Inflammation Research Articles

Anti-Inflammatory Effect of Nicavet-2500 in Rodent Models of Acute Inflammation

This study examines the influence of the tissue preparation "NICAVET 2500" on an organism of mammals with use of rodent models of acute inflammation. It is established that action of a preparation leads to decrease in ESR. Hematologic and biochemical parameters also testify to anti-inflammatory action of "NICAVET 2500". Results of histological and morphometric research of a spleen and a thymus show processes of proliferation and migration of immunocytes, testifying to activization of immune reactions. In a thymus of rats of experimental group in comparison with control an increase in the dimensions of thymic lobules and also an increase in quantity of Hassal's bodies, testifying to intensification of synthesis of the thymic hormones participating in process of an immunopoesis are revealed. As a result of the use of the preparation an increase of ability of an organism to resist alteration and also essential decrease in a level of development of inflammatory reaction of an organism are observed. The conducted research demonstrates the expressed immunomodulatory action of a preparation "NICAVET 2500" at an experimental model of inflammation.

4-Methyl-2,2-dioxo-1H-2λ⁶,1-benzothiazine-3-carboxylic Acid. Peculiarities of Preparation, Structure, and Biological Properties.

In order to determine the regularities of the structure–analgesic activity relationship, the peculiarities of obtaining, the spatial structure, and biological properties of 4-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylic acid and some of its derivatives have been studied. Using nuclear magnetic resonance (NMR) spectroscopy and X-ray diffraction analysis, it has been proven that varying the reaction conditions using alkaline hydrolysis of methyl 4-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylate makes it possible to successfully synthesize a monohydrate of the target acid, its sodium salt, or 4-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine. The derivatographic study of the thermal stability of 4-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylic acid monohydrate has been carried out; based on this study, the optimal conditions completely eliminating the possibility of unwanted decomposition have been proposed for obtaining its anhydrous form. It has been shown that 4-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine is easily formed during the decarboxylation of not only 4-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylic acid, but also its sodium salt, which is capable of losing СО2 both in rather soft conditions of boiling in an aqueous solution, and in more rigid conditions of dry heating. The NMR spectra of the compounds synthesized are given; their spatial structure is discussed. To study the biological properties of 4-methyl-2,2-dioxo-1H-2λ6,1-benzothiazine-3-carboxylic acid and its sodium salt, the experimental model of inflammation caused by subplantar introduction of the carrageenan solution in one of the hind limbs of white rats was used. The anti-inflammatory activity and analgesic effect were assessed by the degree of edema reduction and the ability to affect the pain response compared to the animals of control groups. According to the results of the tests performed, it has been found that after intraperitoneal injection, the substances synthesized demonstrate a moderate anti-inflammatory action and simultaneously increase the pain threshold of the experimental animals very effectively, exceeding Lornoxicam and Diclofenac in a similar dose by their analgesic activity.

Alternative and Natural Therapies for Acute Lung Injury and Acute Respiratory Distress Syndrome.

Introduction Acute respiratory distress syndrome (ARDS) is a complex clinical syndrome characterized by acute inflammation, microvascular damage, and increased pulmonary vascular and epithelial permeability, frequently resulting in acute respiratory failure and death. Current best practice for ARDS involves “lung-protective ventilation,” which entails low tidal volumes and limiting the plateau pressures in mechanically ventilated patients. Although considerable progress has been made in understanding the pathogenesis of ARDS, little progress has been made in the development of specific therapies to combat injury and inflammation. Areas Covered In recent years, several natural products have been studied in experimental models and have been shown to inhibit multiple inflammatory pathways associated with acute lung injury and ARDS at a molecular level. Because of the pleiotropic effects of these agents, many of them also activate antioxidant pathways through nuclear factor erythroid-related factor 2, thereby targeting multiple pathways. Several of these agents are prescribed for treatment of inflammatory conditions in the Asian subcontinent and have shown to be relatively safe. Expert Commentary Here we review natural remedies shown to attenuate lung injury and inflammation in experimental models. Translational human studies in patients with ARDS may facilitate treatment of this devastating disease.

Fisetin, a PPAR gamma agonist improves myocardial injury in rats through Inhibition of MAPK Signalling Pathway mediated oxidative stress and inflammation in Experimental Model of Myocardial Ischemia Reperfusion Injury

Fisetin, a PPAR gamma agonist improves myocardial injury in rats through Inhibition of MAPK Signalling Pathway mediated oxidative stress and inflammation in Experimental Model of Myocardial Ischemia Reperfusion Injury

Suppression of inflammation and acquired immunity by IL-37.

IL-37 is a unique member of the IL-1 family of cytokines, which functions as a natural suppressor of inflammatory and immune responses. Immune and non-immune cells produce IL-37 precursor following pro-inflammatory stimuli. Following activating cleavage by caspase-1, mature IL-37 translocates to the nucleus, where it suppresses transcription of pro-inflammatory genes. Both precursor and mature IL-37 are also secreted in the extracellular space, where they bind IL-18Rα and recruit the IL-1R8 (formerly TIR8 or SIGIRR), which transduces anti-inflammatory signals by suppressing NF-kB and MAPK and by activating Mer-PTEN-DOK pathways. During inflammation, IL-37 restores the metabolism of the cell by reducing succinate, inhibiting mTOR, and activating AMPK. Transgenic mice expressing human IL-37 and wild type mice treated with recombinant human IL-37 are protected from several experimental models of inflammation, including endotoxin shock, colitis, lung and spinal cord injury, coronary artery disease, arthritis and inflammation-induced fatigue, while also exhibiting reduced adaptive immune responses. In humans, IL-37 likely functions to limit excessive inflammation: accordingly, IL-37 levels are abnormal in patients with inflammatory and autoimmune diseases. In this review, we provide an overview of the discovery and biology of IL-37, and discuss the potential for development of this cytokine as a therapeutic agent.

The Anti-Inflammatory and Antioxidant Effects of Salvia officinalis on Lipopolysaccharide-Induced Inflammation in Rats.

Salvia officinalis, which has a high phenolic acid and flavonoid content, is a powerful antioxidant and anti-inflammatory herb. Inflammation plays an important role in the pathophysiology of many diseases and could cause damage by means of oxidative stress. The aim of this study was to investigate the anti-inflammatory and antioxidant activity of S. officinalis formed lipopolysaccharide (LPS)-induced experimental inflammation model. Four- to five-month-old 42 female Wistar albino rats were divided into six groups. Three groups were administered intraperitoneally 1 mg/kg LPS. Twenty-four hours after injection of LPS, 10 and 30 mg/kg S. officinalis extract were given orally to treatment groups. Pulmonary and hepatic 18F-fluoro-deoxy-D-glucose (18F-FDG) uptake was calculated to determine the status of inflammation by 18F-fluoro-deoxy-D-glucose-positron emission tomography (18FDG-PET) scan. Antioxidant enzyme activities and nitric oxide (NO) and malondialdehyde (MDA) levels were determined. Nuclear factor-kappa B (NF-κB) and tumor necrosis factor-alpha (TNF-α) levels were also detected in serum. As a result, lung and liver 18F-FDG uptake was found to be higher in the inflammation group than control group. MDA levels in erythrocyte and all tissue samples (liver, lung, and kidney) were found to be significantly higher compared to treatment groups. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase activities of the inflammation group in the liver, lung, kidney tissues, and erythrocyte SOD and CAT activities were determined to significantly lower than groups treated with S. officinalis. Increased NO, NF-κB, and TNF-α levels were found in the inflammation group. S. officinalis has been observed to have useful effects on LPS-induced inflammation and oxidative stress in rats.

Monitoring C5aR2 Expression Using a Floxed tdTomato-C5aR2 Knock-In Mouse.

The biological significance of C5a receptor [(C5aR)2/C5L2], a seven-transmembrane receptor binding C5a and C5adesArg, remains ill-defined. Specific ligation of C5aR2 inhibits C5a-induced ERK1/2 activation, strengthening the view that C5aR2 regulates C5aR1-mediated effector functions. Although C5aR2 and C5aR1 are often coexpressed, a detailed picture of C5aR2 expression in murine cells and tissues is still lacking. To close this gap, we generated a floxed tandem dye (td)Tomato-C5aR2 knock-in mouse that we used to track C5aR2 expression in tissue-residing and circulating immune cells. We found the strongest C5aR2 expression in the brain, bone marrow, and airways. All myeloid-derived cells expressed C5aR2, although with different intensities. C5aR2 expression in blood and tissue neutrophils was strong and homogeneous. Specific ligation of C5aR2 in neutrophils from tdTomato-C5aR2 mice blocked C5a-driven ERK1/2 phosphorylation, demonstrating functionality of C5aR2 in the reporter mice. In contrast to neutrophils, we found tissue-specific differences in C5aR2 expression in eosinophils, macrophages, and dendritic cell subsets. Naive and activated T cells stained negative for C5aR2, whereas B cells from different tissues homogeneously expressed C5aR2. Also, NK cell subsets in blood and spleen strongly expressed C5aR2. Activation of C5aR2 in NK cells suppressed IL-12/IL-18-induced IFN-γ production. Intratracheal IL-33 challenge resulted in decreased C5aR2 expression in pulmonary eosinophils and monocyte-derived dendritic cells. In summary, we provide a detailed map of murine C5aR2 immune cell expression in different tissues under steady-state conditions and upon pulmonary inflammation. The C5aR2 knock-in mouse will help to reliably track and conditionally delete C5aR2 expression in experimental models of inflammation.

Vitex agnus-castus dry extract BNO 1095 (Cyclodynon®) inhibits uterine hyper-contractions and inflammation in experimental models for primary dysmenorrhea

Background. For many women, the monthly suffering induced by menstrual “cramps” is severe enough to profoundly disrupt their quality of life. In the case of primary dysmenorrhea, a condition related to premenstrual syndrome (PMS), intense uterine contractions are thought to trigger moderate to intense pain despite the absence of an underlying infection or other medically-identifiable disease states. The associated uterine hyper-contractility is reminiscent of labor, and associated pain is likely to be mediated by the release of prostaglandins, leukotrienes and the infiltration of leukocytes that normally accompany the breakdown of the endometrial lining.Standardized extracts of Vitex agnus-castus berries (VAC extracts of chaste tree, or chaste berries) are clinically effective in treating the symptoms of PMS, yet the mechanisms of how the chemically complex mixture acts are largely unknown.Methods. Using an in vivo dysmenorrhea model rats were treated with 10 mg/kg estradiol-benzoate i.p. once daily for 12 days and with 2.1, 10.3 or 20.7 mg/kg VAC dry extract p.o. once daily for 7 days prior to induction of convulsions. Uterine contractions where induced with 2 IU/kg oxytocin i.p., followed by monitoring of abdominal convulsions and signs of pain on the last day of the experiment. Moreover, in vitro methods were applied that are described in the methods section.Results. Here, we show that the VAC herbal dry extract BNO 1095 (commercially available as Cyclodynon®) targets the uterine myometrial tissue and inflammatory signaling molecules of associated migratory/inflammatory cells. Specifically, BNO 1095 dose-dependently inhibited oxytocin-induced uterine contractions in a rat dysmenorrhea model in vivo and drug-induced contractions in isolated human and rat uterine tissue in vitro. Furthermore, BNO 1095 showed a promising anti-inflammatory capacity by potently inhibiting 5-lipoxygenase activity and leukotriene production and by reducing the production of reactive oxygen species and inflammatory cytokines in vitro.Conclusion. These results provide evidence that BNO 1095 effectively treats menstruation-related complaints including primary dysmenorrhea.

Mild intracellular acidification by dexamethasone attenuates mitochondrial dysfunction in a human inflammatory proximal tubule epithelial cell model

Septic acute kidney injury (AKI) associates with poor survival rates and often requires renal replacement therapy. Glucocorticoids may pose renal protective effects in sepsis via stimulation of mitochondrial function. Therefore, we studied the mitochondrial effects of dexamethasone in an experimental inflammatory proximal tubule epithelial cell model. Treatment of human proximal tubule epithelial cells with lipopolysaccharide (LPS) closely resembles pathophysiological processes during endotoxaemia, and led to increased cytokine excretion rates and cellular reactive oxygen species levels, combined with a reduced mitochondrial membrane potential and respiratory capacity. These effects were attenuated by dexamethasone. Dexamethasone specifically increased the expression and activity of mitochondrial complex V (CV), which could not be explained by an increase in mitochondrial mass. Finally, we demonstrated that dexamethasone acidified the intracellular milieu and consequently reversed LPS-induced alkalisation, leading to restoration of the mitochondrial function. This acidification also provides an explanation for the increase in CV expression, which is expected to compensate for the inhibitory effect of the acidified environment on this complex. Besides the mechanistic insights into the beneficial effects of dexamethasone during renal cellular inflammation, our work also supports a key role for mitochondria in this process and, hence, provides novel therapeutic avenues for the treatment of AKI.

Milonine, a Morphinandienone Alkaloid, Has Anti-Inflammatory and Analgesic Effects by Inhibiting TNF-α and IL-1β Production.

Milonine is a morphinandienone alkaloid from Cissampelos sympodialis Eichl (Menispermaceae), a plant used in Brazil to treat inflammatory disorders. In this study, we evaluated the anti-inflammatory and analgesic activity of milonine (MIL) by using classical experimental models of inflammation and nociception. The results showed that MIL reduced the paw edema formation induced by lipopolysaccharide, prostaglandin E2, and bradykinin, without interfering with the serotonin-induced edema. With respect to the nociception experiments, MIL decreased the exudate into the peritoneum induced by acetic acid, maintaining the tissue morphology. The alkaloid was able to inhibit the peritonitis induced by carrageenan, decreasing mainly the migration of polymorphonuclear cells, without altering the mononuclear cell number, and reduced the levels of TNF-α and IL-1β in the peritoneum. In addition, MIL was able to decrease the frequency of abdominal writhing induced by acetic acid but did not increase the latency time of the animals in the hot plate test. MIL significantly reduced the nociceptive behavior of paw licking induced by formalin only at the second phase of the test. In conclusion, we demonstrate that milonine has anti-inflammatory and anti-nociceptive activities by inhibiting mediators essential for the inflammatory process.

Positron emission tomography tracer [68GA]NODAGA-EXENDIN-4 detects glucagon-like peptide-1 receptor expression in mouse atherosclerotic vascular lesions

Aim: Pharmacological activation of glucagon-like peptide-1 receptor (GLP-1R) signalling attenuates the development of atherosclerosis and vascular inflammation in experimental models. We evaluated whether positron emission tomography (PET) tracer [68Ga]NODAGA-Exendin-4 enables detection of GLP-1R expression in the aorta of atherosclerotic and diabetic mice.

Gut microbiota and obesity: implications for fecal microbiota transplantation therapy.

Obesity is a major public health issue as it is causally associated with several chronic disorders, including type-2 diabetes, cerebrovascular disease (CVD), and cancer. In the United States and other countries worldwide, the obesity epidemic has drastically impacted the status of health of millions as well as healthcare costs. Aside from poor diet, hygiene, and genetics, there are many other factors thought to play an important role in the emergence of obesity. Nowadays, accumulating evidence is elucidating the relation of dysbiosis of intestinal bacteria with obesity and metabolic disorders. Certain gut microbial strains have been shown to inhibit or attenuate immune responses related to chronic inflammation in experimental models, suggesting that specific species among gut microbiota may play either a protective or a pathogenic role in the progression of obesity. Fecal microbiota transplantation (FMT) can therefore represent a therapeutic approach for obesity treatment. FMT is a relatively straightforward therapy that manipulates the human gastrointestinal (GI) microbiota by transferring healthy donor microbiota into an existing but disturbed microbial ecosystem. However, the relevant scientific work is still in its early stages. In this review, we summarize the cutting-edge research being done into FMT treatment of obesity, current issues in FMT treatment, and the future of FMT and microbial therapeutics.

Monitoring C3aR Expression Using a Floxed tdTomato-C3aR Reporter Knock-in Mouse.

C3a exerts multiple biologic functions through activation of its cognate C3a receptor. C3-/- and C3aR-/- mice have been instrumental in defining important roles of the C3a/C3aR axis in the regulation of acute and chronic inflammatory diseases, including ischemia/reperfusion injury, allergic asthma, autoimmune nephritis, and rheumatoid arthritis. Surprisingly little is known about C3aR expression and function in immune and stromal cells. To close this gap, we generated a floxed tandem-dye Tomato (tdTomato)-C3aR reporter knock-in mouse, which we used to monitor C3aR expression in cells residing in the lung, airways, lamina propria (LP) of the small intestine, brain, visceral adipose tissue, bone marrow (BM), spleen, and the circulation. We found a strong expression of tdTomato-C3aR in the brain, lung, LP, and visceral adipose tissue, whereas it was minor in the spleen, blood, BM, and the airways. Most macrophage and eosinophil populations were tdTomato-C3aR+ Interestingly, most tissue eosinophils and some macrophage populations expressed C3aR intracellularly. BM-derived dendritic cells (DCs), lung-resident cluster of differentiation (CD) 11b+ conventional DCs (cDCs) and monocyte-derived DCs, LP CD103+, and CD11b+ cDCs but not pulmonary CD103+ cDCs and splenic DCs were tdTomato-C3aR+ Surprisingly, neither BM, blood, lung neutrophils, nor mast cells expressed C3aR. Similarly, all lymphoid-derived cells were tdTomato-C3aR-, except some LP-derived type 3 innate lymphoid cells. Pulmonary and LP-derived epithelial cells expressed at best minor levels of C3aR. In summary, we provide novel insights into the expression pattern of C3aR in mice. The floxed C3aR knock-in mouse will help to reliably track and conditionally delete C3aR expression in experimental models of inflammation.

In vivo anti-inflammatory activity of aqueous extract of Teucrium polium against carrageenan-induced inflammation in experimental models

The aim of this study was to evaluate the anti-inflammatory activity of Teucrium polium (TP). Rats were divided into four groups: group 1 controls received standard diet; group 2 inflamed by carrageenan (Carr) (1% Carr); group 3 as reference inflamed with Carr and treated with Indometacine (Ind) (150 mg/kg bw) and group 4 inflamed with Carr and pre0treated with TP (5 g/L). Oedema volume was measured 1 h to 5 h after injection. Administration of TP or Ind decreased the levels of hematology parameters relative to Carr and reduced the volume of rats induced by Carr. TP reduced levels of CRP, fibrinogen compared to treated, a decrease in oxidative stress (LP) and AOPP with an increase in the levels of SOD, CAT, GPx and Vit C in skin and erythrocytes. Carr increased the levels of lipid peroxidation and decreased levels of antioxidant enzymatic and Vit C. Our results were confirmed by histological sections of skin.

English

Atemoya, from family Annonaceae, is an interspecific hybrid between Annona cherimola Mill and Annona squamosa L. It is a tree from a region in diversity of plants, the Caatinga, one of the main Brazilian biomes. In this research, the effects of ethanolic extract of atemoya (Acs-EtOH) were investigated in relief of pain and inflammation in experimental models in rodents. The evaluation of antinociceptive activity was carried out by the acetic acid-induced writhing, formalin and hot plate tests, while air pouch and carrageenan-induced peritonitis were used for anti-inflammatory profile. The motor coordination evaluation was performed by rota-rod test. Acs-EtOH (25, 50 and 100 mg/kg, p.o.) significantly reduced the number of writhes with significant (p < 0.001) and decreased (p < 0.001) paw licking time in both phases of the formalin test. In the hot plate test, the latency was significant, reducing painful stimulus. In the anti-inflammatory models, Acs-EtOH inhibited significantly (p < 0.001) the migration of leukocytes in the air pouch and peritonitis tests. Significant inhibition of migration of leukocytes in the treated groups with different doses of the extract was observed. The results indicate that Acs-EtOH may provide a source of plant compounds with antinociceptive and anti-inflammatory activities.   Key words: Annonaceae, pain, inflammation, medicinal plants, caatinga.

Augmented liver targeting of exosomes by surface modification with cationized pullulan.

Exosomes have shown potentials as therapeutics for various inflammatory disease models. This study is the first to show the specific accumulation of exosomes in the liver and enhanced anti-inflammatory effect via the surface modification of exosomes using pullulan, which is specifically recognized by the asialoglycoprotein receptor (AGPR) on HepG2 cells and hepatocytes. The pullulan was expressed on the surface of PKH-labeled exosomes, and it led increased accumulation of PKH into HepG2 cells, whereas the accumulation was canceled by AGPR inhibitor. In the mouse liver injury model, the modification of PKH-labeled exosomes with pullulan enabled increased accumulation of PKH specifically in the injured liver. Furthermore the greater therapeutic effects against the liver injury compared with unmodified original exosomes was observed.

Light-Emitting Diode treatment ameliorates allergic lung inflammation in experimental model of asthma induced by ovalbumin.

Since asthma is a multifactorial disease where treatment sometimes is not effective, new therapies that improve the respiratory discomfort of patients are of great importance. Phototherapy as Light-emitting diode (LED) has emerged as a treatment that presents good results for diseases that are characterized by inflammation. Thus, our objective was to investigate the effects of LED on lung inflammation, by an evaluation of lung cell infiltration, mucus secretion, oedema, and the production of cytokines. Male Balb/c mice were or not sensitized and challenged with ovalbumin (OVA) and treated or not with LED therapy (1 h and 4 h after each OVA challenge). Twenty-four hours after the last OVA challenge, analyzes were performed. Our results showed that LED treatment in asthmatic mice reduced the lung cell infiltration, the mucus production, the oedema, and the tracheal's contractile response. It also increased the IL-10 and the IFN-gamma levels. The effects of LED treatment on lung inflammation may be modulated by IL-10, IFN-gamma, and by mast cells. This study may provide important information about the effects of LED, and in addition, it may open the possibility of a new approach for the treatment of asthma.

Evaluation of the Anti-Inflammatory Effect of Pioglitazone in Experimental Models of Inflammation in Rats

The antidiabetic thiozolidinediones (TZDs) a class of peroxisome proliferators-activated receptor (PPAR) ligands has recently been the focus of much interest for their possible role in regulation of inflammatory response. The present study was designed to evaluate the anti-inflammatory activity of pioglitazone in experimental models of inflammation in rats. The present study was conducted to evaluate the anti inflammatory effect of TZDs (pioglitazone 3mg/Kg) on acute, sub acute and chronic model of inflammation by using egg-albumin and formalin–induced paw edema in 72 rats, relative to reference drugs Dexamethasone 5mg/Kg and Piroxicam 5mg/Kg. In each inflammation model, 24 rats were allocated into four subgroups, each containing six rats representing control, two standards, and test groups. All treatments were given (I.P) 30 minutes before induction of inflammation and the increase in paw edema was measured at certain time intervals by using vernier caliper. Pioglitazone produced nonsignificant reduction (P>0.05) of egg albumin-induced acute inflammation of the rat hind paw, while significantly produced time-related reduction of formalin-induced sub-acute and chronic inflammation of the rat hind paw. In conclusion, pioglitazone possesses anti-inflammatory activity in the animal models of sub-acute and chronic inflammations.
 Key Words: Pioglitazone, PPAR-γ, anti-inflammatory activity

Anti-inflammatory and anti-nociceptive effects of strontium ranelate on the zymosan-induced temporomandibular joint inflammatory hypernociception in rats depend on TNF-α inhibition.

Temporomandibular joint (TMJ) disorders show inflammatory components, heavily impacting on quality of life. Strontium ranelate has previously shown anti-inflammatory and antinociceptive effects on other experimental inflammatory pain models. Thus, we aim to investigate the strontium ranelate efficacy in reducing the zymosan-induced inflammatory hypernociception in the TMJ of rats by evaluating the TNF-α, IL-1β, and hemeoxygenase-1 (HO-1) involvement. Wistar rats were treated with strontium ranelate (0.5, 5 or 50 mg/kg, per os) 1 h before zymosan injection (iart). Mechanical threshold was assessed by Von Frey test and synovial lavage was collected for leukocyte counting and myeloperoxidase measurement, joint tissue and trigeminal ganglion were excised for histopathological analysis (H&E) and TNF-α/IL-1β levels dosage (ELISA). Moreover, rats were pre-treated with ZnPP-IX (3 mg/kg, sc), a specific HO-1 inhibitor, before strontium ranelate administration (0.5 mg/kg, per os), and Evans Blue (5 mg/kg, iv) was administered to assess plasma extravasation. Pre-treatment with indomethacin (5 mg/kg, sc) was used as positive control while the sham group received 0.9% sterile saline (per os and iart). Strontium ranelate did not reduce leukocyte counting, myeloperoxidase activity, Evans Blue extravasation, IL-1β levels, and TNF-α/IL-1β immunolabeling; but it increased the nociceptive threshold and reduced TNF-α levels. Additionally, HO-1 inhibition did not change the strontium ranelate effects. Strontium ranelate may achieve its antinociceptive effects through the reduction of TNF-α levels in the trigeminal ganglion, but not suppressing IL-1β expression nor inducing the HO-1 pathway.

A Low Concentration of Tacrolimus/Semifluorinated Alkane (SFA) Eyedrop Suppresses Intraocular Inflammation in Experimental Models of Uveitis.

Purpose: Corticosteroids remain the mainstay therapy for uveitis, a major cause of blindness in the working age population. However, a substantial number of patients cannot benefit from the therapy due to steroids resistance or intolerance. Tacrolimus has been used to treat refractory uveitis through systemic administration. The aim of this study was to evaluate the therapeutic potential of 0.03% tacrolimus eyedrop in mouse models of uveitis. Methods: 0.03% tacrolimus in perfluorobutylpentane (F4H5) (0.03% Tacrolimus/SFA) was formulated using a previously published protocol. Tacrolimus suspended in PBS (0.03% Tacrolimus/PBS) was used as a control. In addition, 0.1% dexamethasone (0.1% DXM) was used as a standard therapy control. Endotoxin-induced uveitis (EIU) and experimental autoimmune uveoretinitis (EAU) were induced in adult C57BL/6 mice using protocols described previously. Mice were treated with eyedrops three times/day immediately after EIU induction for 48 h or from day 14 to day 25 post-immunization (for EAU). Clinical and histological examinations were conducted at the end of the experiment. Pharmacokinetics study was conducted in mice with and without EIU. At different times after eyedrop treatment, ocular tissues were collected for tacrolimus measurement. Results: The 0.03% Tacrolimus/SFA eyedrop treatment reduced the clinical scores and histological scores of intraocular inflammation in both EIU and EAU to the levels similar to 0.1% DXM eyedrop treatment. The 0.03% Tacrolimus/PBS did not show any suppressive effect in EIU and EAU. Pharmacokinetic studies showed that 15 min after topical administration of 0.03% Tacrolimus/SFA, low levels of tacrolimus were detected in the retina (48 ng/g tissue) and vitreous (2.5 ng/ml) in normal mouse eyes, and the levels were significantly higher in EIU eyes (102 ng/g tissue in the retina and 24 ng/ml in the vitreous). Tacrolimus remained detectable in intraocular tissues of EIU eyes 6 h after topical administration (68 ng/g retinal tissue, 10 ng/ml vitreous). Only background levels of tacrolimus were detected in the retina (2-8 ng/g tissue) after 0.03% Tacrolimus/PBS eyedrop administration. Conclusion: 0.03% Tacrolimus/SFA eyedrop can penetrate ocular barrier and reach intraocular tissue at therapeutic levels in mouse eyes, particularly under inflammatory conditions. 0.03% Tacrolimus/SFA eyedrop may have therapeutic potentials for inflammatory eye diseases including uveitis.