Tacrolimus downregulates inflammation by regulating pro‑/anti‑inflammatory responses in LPS‑induced keratitis

Lower levels of FOXP3 are associated with prolonged inflammatory responses in kidney transplant recipients

Background

Immunosuppressive treatment of kidney transplant recipients is mainly aimed at pro-inflammatory T effector cells, yet they also target the immunosuppressive T regulatory cells. Here, we test the hypothesis that low levels of the master gene regulator of T regulatory cells, forkhead box P3 (FOXP3) splice variants, are associated with prolonged inflammatory responses to stimuli.

Methods

From blood samples obtained the first - and 29th day post-transplant, we extracted peripheral blood mononuclear cells and measured mRNA levels of Total FOXP3, pre-mature RNA FOXP3 (pre-mRNA FOXP3), full length FOXP3 (FOXP3fl) and, FOXP3 splice variant excluding exon two (FOXP3d2). We defined the primary outcome as the number of days in which C reactive protein (CRP) was above 50 mg/L. CRP levels were gathered in two periods, the first from the second to 29 days post-transplant, and the second from 30 to 57 days post-transplant. The association was tested using adjusted negative binomial regression.

Results

From 507 included kidney transplant recipients, 382 recipients had at least one CRP measurement >50 mg/L in the first period, median duration of elevated CRP was 4 days [interquartile range (IQR) 2 to 6]. In the second period, 69 recipients had at least one CRP measurement >50 mg/L, median duration of elevated CRP was 3 days [IQR 2 to 5]. In the first period, we found a significant association between lower levels of Total FOXP3 and prolonged duration of CRP elevation, incidence rate ratio 0.61 (95% confidence interval 0.46-0.80), p<0.01.

Conclusion

Lower levels of total FOXP3 mRNA levels in peripheral blood of kidney transplant recipients are associated with prolonged duration of inflammatory responses regardless of the underlying stimuli.

Hypothetical protein FoDbp40 influences the growth and virulence of Fusarium oxysporum by regulating the expression of isocitrate lyase

Fungal growth is closely related to virulence. Finding the key genes and pathways that regulate growth can help elucidate the regulatory mechanisms of fungal growth and virulence in efforts to locate new drug targets. Fusarium oxysporum is an important plant pathogen and human opportunistic pathogen that has research value in agricultural and medicinal fields. A mutant of F. oxysporum with reduced growth was obtained by Agrobacterium tumefaciens-mediated transformation, the transferred DNA (T-DNA) interrupted gene in this mutant coded a hypothetical protein that we named FoDbp40. FoDbp40 has an unknown function, but we chose to explore its possible functions as it may play a role in fungal growth regulatory mechanisms. Results showed that F. oxysporum growth and virulence decreased after FoDbp40 deletion. FOXG_05529 (NCBI Gene ID, isocitrate lyase, ICL) was identified as a key gene that involved in the reduced growth of this mutant. Deletion of FoDbp40 results in a decrease of more than 80% in ICL expression and activity, succinate level, and energy level, plus a decrease in phosphorylated mammalian target of rapamycin level and an increase in phosphorylated 5′-adenosine monophosphate activated protein kinase level. In summary, our study found that the FoDbp40 regulates the expression of ICL at a transcriptional level and affects energy levels and downstream related pathways, thereby regulating the growth and virulence of F. oxysporum.

Lipopolysaccharide Enhances Genotoxicity by Activating GADD45G and NF-κB in Human Corneal Epithelial Cells

As the prevalence of microbial keratitis increases, it creates an environment conducive to genotoxicity response. A potential connection between growth arrest and DNA-damage-inducible 45 gamma (GADD45G) gene expression has not been proven in the corneal epithelial cells. The aim of this study was to determine whether lipopolysaccharide (LPS) enhances genotoxicity, DNA damage, and inflammatory responses in human corneal epithelial cells (HCECs) in vitro. In a set of parameters, cytotoxicity, reactive oxygen species, mitochondrial membrane potential, DNA damage, inflammatory response, and apoptosis were assessed. LPS (1, 5, and 10 μg/mL) treated HCECs were increased reactive oxygen species formation, mitochondrial membrane depolarization, and genotoxicity in a concentration-dependent manner. Similarly, NF-κB, PARP1, and TP53 were also overexpressed in the LPS treated HCECs. 24 hours after LPS induction, micronucleus scoring, and proapoptotic factors were also increased. Among them, the GADD45G, NF-κB, and γH2AX were overexpressed both on the mRNA and protein levels in LPS (10 μg/mL) treated HCECs. In our study, we show that the GADD45G signaling can trigger genotoxic instability in HCECs exposed to LPS. Therefore, understanding the factors contributing to infectious keratitis, such as GADD45G, NF-κB, and γH2AX signaling, may help to develop antigenotoxic and anti-inflammatory therapies for corneal dystrophy and epithelial cell remodeling.

A periodontal tissue regeneration strategy via biphasic release of zeolitic imidazolate framework-8 and FK506 using a uniaxial electrospun Janus nanofiber

Guided tissue regeneration (GTR) strategies are an effective approach to repair periodontal defects by using GTR membranes. However, commercial GTR membranes still have limitations in periodontal tissue regeneration owing to lack of antibacterial and osteogenic properties. The development of novel Janus nanofibers with biphasic release characteristics based on the therapeutic needs of GTR is essential to tackle this issue. Here, we developed a multifunctional Janus nanofiber via uniaxial electrospinning, with zeolitic imidazolate framework-8 nanoparticle (ZIF-8 NP) loading in the hydrophilic polyvinylpyrrolidone (PVP) part and FK506 embedding in the hydrophobic polycaprolactone (PCL) part. The release of Zn²⁺ conformed to the Ritger-Peppas kinetics which could effectively prevent bacterial infection, and the release profile of FK506 was fitted to a first-order equation which could provide persistent osteogenic stimulation for osteogenesis. The periodontal tissue regeneration data from a rat periodontitis model revealed that the multifunctional electrospun Janus nanofibers could be used as an effective bioplatform to restore alveolar bone impairment, compared with the control group. In summary, the Janus nanofibers with biphasic release characteristics quickly exert antibacterial function as well as continuously provide a microenvironment beneficial to the osteogenesis process, demonstrating its great potential for GTR treatment in dental clinic applications.

Trichostatin A inhibits dendritic cell maturation through down-regulating NF-κ B (p65) pathway

BACKGROUND

Recent evidence suggested that histone deacetylase inhibitor (HDACi) could inhibit dendritic cell (DC) maturation. However, the mechanism is unclear. Here, we aimed to study whether Trichostatin A (TSA), the most widely studied HDACi, inhibits the maturation of DCs by down-regulating NF-κB (p65) pathway.

METHODS AND RESULTS

Mouse bone marrow-derived DCs were cultured. Lipopolysaccharide (LPS) was applied as stimulation for maturation. Triptolide (TTL) was applied as p65 inhibitor. Microphotography and flow cytometry showed that TSA and p65 inhibitor separately inhibited the maturation of DCs stimulated by LPS from the aspects of cell morphology and cell phenotype. Mixed lymphocyte reaction test and ELISA showed that TSA and p65 inhibitor synergistically inhibited the proliferation of T lymphocytes stimulated by DCs, reduced the secretion of pro-inflammatory cytokine IL-12 and elevated the secretion of anti-inflammatory cytokine IL-10. Western blot and RT-qPCR showed that TSA down-regulated the expression of phosphorylated IκBα, phosphorylated-p65, Ikkβ and Ikkγ, suggesting TSA down-regulates NF-κB (p65) pathway.

CONCLUSIONS

TSA inhibits DC maturation through down-regulating NF-κB (p65) pathway.

In vitro study on immune response modifiers as novel medical treatment options for cholesteatoma

OBJECTIVES

To investigate cytokine profile of cholesteatoma and to collect information about important intercellular signaling pathways by establishing two different cell culture models, to block important intercellular signaling pathways in cholesteatoma by applying immune system modifier drugs to develop alternative medical therapy options for cholesteatoma.

METHODS

To observe the pathogenesis of cholesteatoma and to apply the immunomodulatory drugs, cholesteatoma tissue culture models were constituted with HEKa cells and cholesteatoma keratinocytes, which were obtained from 3 patients who underwent operations for cholesteatoma. Medicines including 5-fluorourasil, imiquimod, cyclosporine, and tacrolimus were applied on both cholesteatoma keratinocytes and HEKa cells. After 48 h of incubation, IL-1, IL-6, IL-8, IL-10, TNF-α, and Ki67 levels were measured to determine cell viability rates.

RESULTS

In the cholesteatoma control group, IL-6 and TNF-α levels were found higher than in the HEKa control group. All repurposed drugs in the study demonstrated anti-inflammatory, anti-proliferative, and cytotoxic effects on cholesteatoma. Imiquimod and tacrolimus in particular are potential treatment prospects for cholesteatoma due to their strong anti-inflammatory and cytotoxic effects.

CONCLUSION

Medical therapy options for cholesteatoma are still missing and surgery is not the ultimate solution. We have focused on intercellular inflammatory processes, which play significant roles in the pathogenesis of cholesteatoma in our paper. Inflammation and proliferation of cholesteatoma decreased after all repurposed drug applications in our study. Anti-inflammatory and anti-proliferative effects of tacrolimus and imiquimod was more significant than other drugs in the study. For this reason, tacrolimus and imiquimod should be examined in depth with in vivo studies in terms of efficacy and safety for medical treatment of cholesteatoma.

Topical tacrolimus nanocapsules eye drops for therapeutic effect enhancement in both anterior and posterior ocular inflammation models

Tacrolimus has shown efficacy in eye inflammatory diseases. However, due to the drug lability, its formulation into a stable ophthalmic product remains a challenge. Tacrolimus-loaded nanocapsules (NCs) were designed for ocular instillation. Further, the stability and effects of the formulation were analyzed under different experimental conditions. Physicochemical characterization of the NCs revealed suitable homogeneous size and high encapsulation efficiency. Moreover, the lyophilized formulation was stable at ICH long term and accelerated storage conditions, for at least 18 and 3 months, respectively. The tacrolimus NCs did not elicit any eye irritation in rabbits after single- and multiple-dose applications. Additionally, ex vivo penetration assays on isolated porcine cornea and pharmacokinetics analyses in various rabbit eye compartments demonstrated the superiority of the NCs in retention and permeation into the anterior chamber of the eye compared to the free drug dissolved in oil. Moreover, multiple dose ocular instillation of the NCs in rats allowed high tacrolimus levels in the eye with very low plasma concentrations. Finally, the developed delivery system achieved a significant decrease in four typical inflammatory markers in a murine model of keratitis, an anterior chamber inflammation. Furthermore, these NCs, applied as eye drops, displayed clinical and histological efficacy in the mainly posterior chamber inflammation model of murine, experimental auto-immune uveitis.

Protective roles of the TIR/BB-loop mimetic AS-1 in alkali-induced corneal neovascularization by inhibiting ERK phosphorylation

Hydrocinnamoyl-L-valylpyrrolidine (AS-1), a synthetic low-molecule mimetic of myeloid differentiation primary response gene 88 (MyD88), inhibits inflammation by disrupting the interaction between the interleukin-1 receptor (IL-1R) and MyD88. Here, we describe the effects of AS-1 on injury-induced increases in inflammation and neovascularization in mouse corneas. Mice were administered a subconjunctival injection of 8 μL AS-1 diluent before or after corneal alkali burn, followed by evaluation of corneal resurfacing and corneal neovascularization (CNV) by slit-lamp biomicroscopy and clinical assessment. Corneal inflammation was assessed by whole-mount CD45⁺ immunofluorescence staining, and corneal hemangiogenesis and lymphangiogenesis following injury were evaluated by immunostaining for the vascular markers isolectin B4 (IB4) and the lymphatic vascularized marker lymphatic vessel endothelial hyaluronan receptor 1 (LYVE1), respectively. Additionally, corneal tissues were collected to determine the expression of 35 cytokines, and we detected activation of IL-1RI, MyD88, and mitogen-activated protein kinase (MAPK). The results showed that alkali conditions increased the number of CD45⁺ cells and expression of vascular endothelial growth factor (VEGF)-A, VEGF-C, and LYVE1 in corneas, with these levels decreased in the AS-1-treated group. Moreover, AS-1 effectively prevented alkali-induced cytokine production, blocked interactions between IL-1RI and MyD88, and inhibited MAPK activation post-alkali burn. These results indicated that AS-1 prevented alkali-induced corneal hemangiogenesis and lymphangiogenesis by blocking IL-1RI-MyD88 interaction, as well as extracellular signal-regulated kinase phosphorylation, and could be efficacious for the prevention and treatment of corneal alkali burn.

Emerging recognition of the complement system in hepatic ischemia/reperfusion injury, liver regeneration and recovery (Review)

Hepatic ischemia/reperfusion injury (IRI) is a result of the ischemic cascade and may occur in the settings of liver trauma, resection and transplantation. Components of the complement system have been indicated to be mediators of hepatic IRI and regulators of liver regeneration. As such, their potential to mediate both beneficial and harmful effects render them key targets for therapy. In the present study, the mechanisms of complement mediating hepatic IRI were discussed with a focus on the different functions of complement in hepatic injury and liver recovery, and an explanation for this apparent paradox is provided, i.e. that the complement products C3a and C5a have an important role in liver damage; however, C3a and C5a are also necessary for liver regeneration. Furthermore, situated at the end of the complement activation cascade, the membrane attack complex is crucial in hepatic IRI and inhibiting the complex with a site-targeted murine complement inhibitor, complement receptor 2-CD59, may improve liver regeneration after partial hepatectomy, even when hepatectomy is combined with ischemia and reperfusion.

Pulmonary surfactant and drug delivery: Vehiculization, release and targeting of surfactant/tacrolimus formulations

This work explores the potential for strategizing pulmonary surfactant (PS) for drug delivery over the respiratory air-liquid interface: the interfacial delivery. The efficacy of PS- and interface-assisted drug vehiculization was determined both in vitro and in vivo using a native purified porcine PS combined with the hydrophobic anti-inflammatory drug Tacrolimus (TAC), a calcineurin inhibitor. In vitro assays were conducted in a novel double surface balance setup designed to emulate compression-expansion dynamics applied to interfacially connected drug donor and recipient compartments. In this setup, PS transported TAC efficiently over air-liquid interfaces, with compression/expansion breathing-like dynamics enhancing rapid interface-assisted diffusion and drug release. The efficacy of PS-assisted TAC vehiculization was also evaluated in vivo in a mouse model of lipopolysaccharide (LPS)-induced acute lung injury (ALI). In anesthetized mice, TAC combined with PS was intra-nasally (i.n) instilled prior administering i.n. LPS. PS/TAC pre-treatment caused greater TAC internalization into a higher number of lung cells obtained from bronchoalveolar lavages (BAL) than TAC pre-treatment alone. Additionally, the PS/TAC combination but not TAC or PS alone attenuated the LPS-induced pro-inflammatory effects reducing cells and proteins in BAL fluid. These findings indicated that PS-mediated increase in TAC uptake blunted the pro-injurious effects of LPS, suggesting a synergistic anti-inflammatory effect of PS/drug formulations. These in vitro and in vivo results establish the potential utility of PS to open novel effective delivery strategies for inhaled drugs.

Self-Assembling Tacrolimus Nanomicelles for Retinal Drug Delivery

Neovascular age-related macular degeneration (AMD) is characterized by an increase in reactive oxygen species (ROS) and pro-inflammatory cytokines in the retinal pigment epithelium cells. The primary purpose of this study was the development of a clear, tacrolimus nanomicellar formulation (TAC-NMF) for AMD. The optimized formulation had a mean diameter of 15.41 nm, a zeta potential of 0.5 mV, and an entrapment efficiency of 97.13%. In-vitro cytotoxicity studies revealed the dose-dependent cytotoxicity of TAC-NMF on various ocular cell lines, such as human retinal pigment epithelium (D407), monkey retinal choroidal endothelial (RF/6A) cells, and human corneal epithelium (CCL 20.2) cells. Cellular uptake and in-vitro distribution studies using flow cytometry and confocal microscopy, respectively, indicated an elevated uptake of TAC-NMF in a time-dependent manner. Biocompatibility assay using macrophage RAW 264.7 cell line resulted in low production of inflammatory cytokines such as IL-6, IL-1β and TNF-α after treatment with TAC-NMF. There was a decrease in ROS in D407 cells pre-treated with sodium iodate (ROS inducing agent) after treating with TAC-NMF and tacrolimus drug. Similarly, there was a reduction in the pro-inflammatory cytokines and VEGF-A in D407 cells pretreated with sodium iodate. This indicates that TAC-NMF could lower pro-inflammatory cytokines and ROS commonly seen in AMD.

Tacrolimus dye drop treatment for the management of early post-operative intraocular inflammation after therapeutic keratoplasty for severe infectious keratitis

The current study investigated the anti-inflammatory effect of 0.1% tacrolimus eye drops for the treatment of therapeutic penetrating keratoplasty (TPK) for severe infectious keratitis during early disease stages and reported the long-term clinical outcomes. The present retrospective study included 20 eyes from patients diagnosed with severe keratitis who underwent TPK surgery. Patients were followed-up for up to 12-18 months. Tacrolimus eye drops were administered 4 times/day starting on the first day post-surgery. Glucocorticoid eye drops were subsequently added to treatment plans one-month post-surgery. All patients were followed-up for the first 3 post-operative days, then examined once a week thereafter for the first month. In early post-operative stages, the states of the grafts (ΔS) and the absorption of intraocular inflammation (S) were observed. ΔS was defined as the difference between the states of the grafts on the first post-operative day (SS1d) and those at one month post-surgery (SS1m). S was calculated as the difference between the inflammation score mean one day post-surgery (T1d) and the mean one-month post-surgery (T1m). For long term clinical outcomes, graft failure rates and complications were recorded. Among the 20 eyes analyzed, the mean T1d, T1m and S were 7.4±2.06, 2.0±2.47 and 5.4±2.13 (P<0.01), respectively. The mean SS1d, SS1m and ΔS were 5.3±1.56, 3.8±1.24 and 1.5±1.5 (P<0.01), respectively. During follow-up, there were 6 cases of corneal graft failure, 4 of which were due to immune rejection and 2 of which were due to complications. The current study concluded that tacrolimus eye drops facilitated the absorption of intraocular inflammation in the early post-operative period of TPK and may extend long term survival of grafts in cases of severe infectious keratitis.