Uveitis: Mechanisms and recent advances in therapy

Use of corticosteroids in non-infectious uveitis - expert consensus in Taiwan

PURPOSE

To offer consensus on the utilization of corticosteroids (CS) for treating non-infectious uveitis in the context of clinical practice in Taiwan. This entails examining the different administration methods, their advantages and disadvantages, and considering alternative treatments according to the prevailing evidence and health policies.

METHODS

Ten ophthalmologists and one rheumatologist convened on December 11, 2022, to review and discuss literature on the topic. The databases explored were the Central Cochrane library, EMBASE, Medline, PUBMED, and Web of Science using relevant keywords. The search spanned from January 1996 to June 2023. After the initial results of the literature review were presented, open voting determined the final statements, with a statement being accepted if it secured more than 70% agreement. This consensus was then presented at significant meetings for further discussions before the final version was established.

RESULTS

A flow chart and nine statements emerged from the deliberations. They address the importance of CS in uveitis management, guidelines for using topical CS, indications for both periocular or intravitreal and systemic therapies, and tapering and discontinuation methods for both topical and systemic CS.

CONCLUSION

While CS are a cornerstone for non-infectious uveitis treatment, their administration requires careful consideration, depending on the clinical situation and the specific type of uveitis. The consensus generated from this article provides a guideline for practitioners in Taiwan, taking into account local health policies and the latest research on the subject. It emphasizes the significance of strategic tapering, the potential for alternative therapies, and the importance of patient-centric care.

Long-term outcomes of noninfectious uveitis treated with systemic immunomodulatory therapy: a retrospective case series

OBJECTIVE

To study the clinical characteristics and long-term outcomes of patients with noninfectious uveitis (NIU) who are treated with systemic immunomodulatory therapy (IMT).

DESIGN

Retrospective case series.

PARTICIPANTS

All consecutive cases of adults with NIU under the care of 5 uveitis subspecialty tertiary care clinics between 2010 to 2021 were included.

METHODS

Patient outcomes were assessed at initial presentation and at the latest available follow-up.

RESULTS

A total of 418 NIU patients receiving IMT therapy with a median age of 46.0 years and 59.3% female were identified. Each patient required an average of 1.4 agents until achieving an optimal response. Following initial treatment with prednisone, patients were most commonly initiated on methotrexate. The top 3 treatments with the highest proportion of optimal treatment response when taken alone or in combination with other agents were infliximab (79.3%), cyclosporine (75%), and adalimumab (70%). The strongest predictors for requiring a greater number of IMTs trialed were younger age, panuveitis, and a chronic or recurrent disease course. Multivariable linear regression analysis suggested that baseline visual acuity at diagnosis was the only significant predictor of final visual acuity (p < 0.001).

CONCLUSIONS

NIU patients on IMT are often trialed on multiple therapeutic agents before achieving an optimal treatment response. Visual acuity at diagnosis is a predictor of final visual outcomes, whereas chronic or recurrent disease course, younger age, and panuveitis are predictors of requiring multiagent treatment regimens.

Anterior chamber inflammation grading methods: A critical review

Assessing anterior chamber inflammation is highly subjective and challenging. Although various grading systems attempt to offer objectivity and standardization, the clinical assessment has high interobserver variability. Traditional techniques, such as laser flare meter and fluorophotometry, are not widely used since they are time-consuming. With the development of optical coherence tomography with high sensitivity, direct imaging offers an excellent alternative to assess objectively inflammation with the potential for automated analysis. We describe various anterior chamber inflammation grading methods and discuss their utility, advantages, and disadvantages.

T cells in ocular autoimmune uveitis: Pathways and therapeutic approaches

Autoimmune uveitis is a non-infectious intraocular condition that affects the uveal tract of the eye and threatens vision if not treated properly. Increasing evidence suggests that activated CD4⁺ T cells are associated with progressive and permanent destruction of photoreceptors in ocular autoimmune diseases. As such, the purpose of this review is to offer an overview of the role of CD4⁺ T cells in autoimmune uveitis as well as a justification for the current development and assessment of innovative autoimmune uveitis medications targeting CD4⁺ T cells. With an emphasis on T helper (Th)17, Th1, and Th2 cells, follicular helper CD4⁺ T cells, and regulatory T cells, this review presents a summary of recent research related to the pathways and signaling that encourage CD4⁺ T cells to develop into specialized effector cells. We also describe immunotherapeutic approaches based on CD4⁺ T cell subsets and their potential as therapeutic agents for autoimmune disorders.

Inhibition of experimental autoimmune uveitis by intravitreal AAV-Equine-IL10 gene therapy

Equine recurrent uveitis (ERU) is a spontaneous, painful, and vision threatening disease affecting up to 25% of equine populations worldwide. Current treatments of ERU are non-specific and have many side effects which limits them to short-term use. In order to develop an effective therapy for ERU, we investigated the use of adeno-associated virus (AAV) gene therapy, exploiting a natural immune tolerance mechanism induced by equine interleukin-10 (Equine-IL10). The purpose of this study was to evaluate the therapeutic efficacy of a single intravitreal (IVT) dose of AAV8-Equine-IL10 gene therapy for inhibition of experimental autoimmune uveitis (EAU) in rats. Each rat was dosed intravitreally (IVT) in both eyes with either balanced salt solution (BSS) (control; n = 4), AAV8-Equine-IL10 at a low dose (2.4x10⁹ vg; n = 5) or high dose (2.4x10¹⁰ vg; n = 5). EAU was induced in all groups of rats 7 days after IVT injections and euthanized 21 days post-injection. Ophthalmic examination and aqueous humor (AH) cell counts were recorded with the observer blinded to the treatment groups. Histopathology and qPCR were performed on selected ocular tissues. Data presented herein demonstrate that AAV8-Equine-IL10 treated rats exhibited a significant decrease in clinical inflammatory scores and AH cell counts compared to BSS-treated EAU eyes on days 10, 12 and 14 post EAU induction at both administered vector doses. Mean cellular histologic infiltrative scores were also significantly less in AAV8-Equine-IL10 dosed rats compared to the BSS group. Intravitreal injection of AAV8-Equine-IL10 resulted in Equine-IL10 cDNA expression in the ciliary body, retina, cornea, and optic nerve in a dose-dependent manner. A single IVT injection of AAV8-Equine-IL10 appeared to be well-tolerated and inhibited EAU even at the lowest administered dose. These results demonstrate safety and efficacy of AAV8-Equine-IL10 to prevent EAU and support continued exploration of AAV gene therapy for the treatment of equine and perhaps human recurrent uveitis.

Therapeutic Applications of Adeno-Associated Virus (AAV) Gene Transfer of HLA-G in the Eye

The purpose of this paper is to review human leukocyte antigen G (HLA-G) in the eye, its role in immune tolerance, and the potential therapeutic use of AAV gene transfer and expression of HLA-G in various ocular tissues. Several studies are reviewed that demonstrate efficacy in animal models of disease, including intracorneal delivery of AAV-HLA-G to treat corneal inflammation and prevent corneal graft rejection, subconjunctival injection of AAV-HLA-G for ocular graft vs. host disease and potentially dry eye disease, and intravitreal injection of AAV-HLA-G to inhibit uveitis. Furthermore, due to the anti-vascular function of HLA-G, AAV-HLA-G may be an effective therapy for posterior ocular diseases, such as neovascular age-related macular degeneration, diabetic retinopathy, and choroidal neovascularization. Therefore, AAV-mediated gene transfer of HLA-G may be an effective treatment for common immune-mediated, inflammatory, and neovascular diseases of the eye.

AAV-mediated expression of HLA-G1/5 reduces severity of experimental autoimmune uveitis

Non-infectious uveitis (NIU) is an intractable, recurrent, and painful disease that is a common cause of vision loss. Available treatments of NIU, such as the use of topical corticosteroids, are non-specific and have serious side effects which limits them to short-term use; however, NIU requires long-term treatment to prevent vision loss. Therefore, a single dose therapeutic that mediates long-term immunosuppression with minimal side effects is desirable. In order to develop an effective long-term therapy for NIU, an adeno-associated virus (AAV) gene therapy approach was used to exploit a natural immune tolerance mechanism induced by the human leukocyte antigen G (HLA-G). To mimic the prevention of NIU, naïve Lewis rats received a single intravitreal injection of AAV particles harboring codon-optimized cDNAs encoding HLA-G1 and HLA-G5 isoforms one week prior to the induction of experimental autoimmune uveitis (EAU). AAV-mediated expression of the HLA-G-1 and -5 transgenes in the targeted ocular tissues following a single intravitreal injection of AAV-HLA-G1/5 significantly decreased clinical and histopathological inflammation scores compared to untreated EAU eyes (p < 0.04). Thus, localized ocular gene delivery of AAV-HLA-G1/5 may reduce the off-target risks and establish a long-term immunosuppressive effect that would serve as an effective and novel therapeutic strategy for NIU, with the potential for applications to additional ocular immune-mediated diseases.

Anti-TNF Drugs for Chronic Uveitis in Adults-A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: We aimed to assess efficacy and safety of anti-tumor necrosis factor (TNF) drugs for adult chronic non-infectious uveitis (NIU).

Methods: CENTRAL, MEDLINE, and EMBASE, were searched from inception to January 2019. Double-masked randomized placebo-controlled trials, assessing any anti-TNF vs. best medical intervention/standard of care in adults with chronic NIU were considered. The PRISMA and SAMPL guidelines were followed. The risk of bias was assessed using the Cochrane risk of bias tool. Overall quality of the evidence was assessed according to GRADE. PROSPERO registration: #CRD42016039068. The primary efficacy and safety outcomes were preservation of visual acuity (VA) and withdrawals due to adverse events, respectively. Meta-analysis of efficacy analysis was not performed due to significant clinical heterogeneity between studies' population and interventions.

Results: A total of 1,157 references were considered and 3 studies were included. The overall risk of bias was moderate. In active NIU, adalimumab group showed an increased likelihood of VA preservation (risk ratio (RR) 1.75, 95%CI 1.32 to 2.32, n = 217), whereas the etanercept group did not (RR 0.81, 95%CI 0.57 to 1.14, n = 20). In inactive NIU, adalimumab was associated with increased likelihood of VA preservation (RR 1.31, 95%CI 1.12 to 1.53, n = 226). The rate of adverse events did not differ between anti-TNF and control arms (RR 1.03, 95%CI 0.94 to 1.13, n = 410).

Conclusions: There is high quality evidence that adalimumab decreases the risk of worsening VA in active and inactive NIU and very low quality evidence that the risk of etanercept worsening VA in inactive NIU is not different from placebo. Moderate quality evidence suggests that anti-TNF agents are not different from placebo on the risk of study withdrawal.

Efficacy and safety of intravitreal anti-tumour necrosis factor drugs in adults with non-infectious uveitis - a systematic review

Anti-tumour necrosis factor (TNF) drugs have been extensively used in non-infectious uveitis (NIU), when corticosteroids or conventional immunosuppressive drugs cannot adequately control inflammation or intolerable side-effects occur. However, systemic anti-TNF therapies are also associated with a myriad of side-effects. Therefore, intravitreal administration of anti-TNF biologics has been employed to minimize patient morbidity and systemic adverse effects, while maintaining therapeutic effectivity. We undertook a systematic review to determine evidence of efficacy and safety of intravitreal administration of anti-TNF drugs in adults with NIU. We conducted this systematic review according to the PRISMA guidelines. The protocol was registered with PROSPERO (CRD42016041946). We searched CENTRAL, MEDLINE and EMBASE, from inception to April 2017, as well as clinical trial registries and grey literature. The qualitative analysis included all studies of adult patients with a diagnosis of NIU and who received intravitreal anti-TNF drugs with a 4-week minimum follow-up. A total of 4840 references were considered for title and abstract screening. Seven full texts were screened, and five studies were considered for analysis. All studies were open-label, single-centre, prospective, non-randomized, interventional case series with a follow-up between 4 and 26 weeks, employing either adalimumab in two studies and infliximab in three. Three studies showed a treatment effect of anti-TNF intravitreal injections, while one study revealed short-term improvement and one study revealed no efficacy of anti-TNF intravitreal therapy. None of the studies reported ocular adverse effects but only two studies included electrophysiological assessment in the safety analysis and no study assessed systemic human anti-drug antibodies. The available evidence is not sufficiently robust to conclude about the clinical effectivity of intravitreal anti-TNF in NIU and so no recommendation can be made. In conclusion, intravitreal injection of anti-TNF antibodies remains a possible treatment option to be explored through robust clinical investigation.

Modern Therapeutic Approaches for Noninfectious Ocular Diseases Involving Inflammation

Dry eye disease, age-related macular degeneration, and uveitis are ocular diseases that significantly affect the quality of life of millions of people each year. In these diseases, the action of chemokines, proinflammatory cytokines, and immune cells drives a local inflammatory response that results in ocular tissue damage. Multiple therapeutic strategies are developed to either address the symptoms or abate the underlying cause of these diseases. Herein, the challenges to deliver drugs to the relevant location in the eye for each of these diseases are reviewed along with current and innovative therapeutic approaches that attempt to restore homeostasis within the ocular microenvironment.

Melatonin as a Therapeutic Resource for Inflammatory Visual Diseases

BACKGROUND

Uveitis and optic neuritis are prevalent ocular inflammatory diseases, and highly damaging ocular conditions. Both diseases are currently treated with corticosteroids, but they do not have adequate efficacy and are often associated with severe side effects. Thus, uveitis and optic neuritis remain a challenging field to ophthalmologists and a significant public health concern.

OBJECTIVE

This review summarizes findings showing the benefits of a treatment with melatonin in experimental models of these inflammatory ocular diseases.

RESULTS

Oxidative and nitrosative damage, tumor necrosis factor, and prostaglandin production have been involved in the pathogeny of uveitis and optic neuritis. Melatonin is an efficient antioxidant and antinitridergic, and has the ability to reduce prostaglandin and tumor necrosis factor levels both in the retina and optic nerve. Moreover, melatonin not only prevents functional and structural consequences of experimental uveitis and optic neuritis, but it is also capable of suppressing the actively ongoing ocular inflammatory response.

CONCLUSIONS

Since melatonin protects ocular tissues against inflammation, it could be a potentially useful anti-inflammatory therapy in ophthalmology.

Anti-inflammatory effect of conditioned medium from human uterine cervical stem cells in uveitis

The aim of the present study was to evaluate the effect of conditioned medium from human uterine cervical stem cells (CM-hUCESCs) in uveitis. To do that, uveitis was induced in rats after footpad injection of Escherichia coli lipopolysaccaride (LPS). Human retinal pigment epithelial (ARPE-19) cells after LPS challenge were used to test anti-inflammatory effect of CM-hUCESCs 'ìn vitro'. Real-time PCR was used to evaluate mRNA expression levels of the pro-inflammatory cytokines interkeukin-6, interkeukin-8, macrophage inflammatory protein-1 alpha, tumor necrosis factor alpha, and the anti-inflammatory interkeukin-10. Leucocytes from aqueous humor (AqH) were quantified in a Neubauer chamber, and eye histopathological analysis was done with hematoxylin-eosin staining. Additionally, using a human cytokine antibody array we evaluated CM-hUCESCs to determine mediating proteins. Results showed that administration of CM-hUCESCs significantly reduced LPS-induced pro-inflammatory cytokines both 'in vitro' and 'in vivo', and decreased leucocytes in AqH and ocular tissues. High levels of cytokines with anti-inflammatory effects were found in CM-hUCESCs, suggesting a possible role of these factors in reducing intraocular inflammation. In summary, treatment with CM-hUCESCs significantly reduces inflammation in uveitis. Our data indicate that CM-hUCESCs could be regarded as a potential therapeutic agent for patients suffering from ocular inflammation.

Red eyes presenting with a fistulous lesion in the left lower extremity: a case report

Introduction

Very few cases of scar sarcoidosis affecting the eyes and bone together have been reported in the last few years.

Case presentation

We report a case of a 49-year-old Spanish man with recurrent bilateral granulomatous uveitis and a fistulous nodular lesion in the left pre-tibial region (scar granuloma) on the site of an 8-year-old scar. He presented with bilateral hilar adenopathies and elevation of inflammatory markers and angiotensin-converting enzyme. A histologically confirmed sarcoid of the tibia with a radiologic appearance unusual for long tubular bone involvement was observed. He also had bilateral ophthalmologic involvement.

Conclusions

Sarcoidosis is a disease of unknown cause histologically characterized by non-caseating granulomas that can involve any organ or tissue. Osseous sarcoidosis is a relatively rare presentation. However, on the basis of cases reported in the literature, sarcoid lesions on bones are generally asymptomatic. Biologic agents are considered an alternative therapy for sarcoidosis resistant to conventional treatment.

IL-1β induces IL-6 production in retinal Müller cells predominantly through the activation of p38 MAPK/NF-κB signaling pathway

IL-6 plays an important role in various inflammatory ocular diseases, including diabetic retinopathy. Müller cells are the major source of inflammatory mediators, including IL-6, in the retina. However, the mechanism of regulating IL-6 production in these cells remains unclear. Examination of signaling pathways in human retinal Müller cells (MIO-M1 cell line) cultured with IL-1β, TNF-α, IL-6, IL-8, VEGF, IFN-γ, glucose or mannitol showed that IL-1β was the most potent stimulator of IL-6 production. In addition, IL-1 β also increased NF-κB p50 protein level and phosphorylation of p38 MAPK, ERK1/2 and c-Jun. Induction of IL-6 production by IL-1β was significantly reduced by addition of p38 MAPK (SB203580), MEK1/2 (U0126) or NF-κB (BAY11-7082) inhibitors, with the highest effect being observed with SB203580. To explore the specific elements in IL-6 promoter responsible for IL-1β-induction of IL-6 expression, a series of plasmids bearing various IL-6 promoter mutations were transiently expressed in MIO-MI cells cultured in the presence or absence of IL-1β (10ng/ml) and/or SB203580 (10µM). Results showed that IL-6 promoter activity of the parent pIL-6-Luc651 was significantly enhanced by IL-1β, but the level was significantly attenuated by SB203580. Furthermore, the IL-6 promoter activity was also reduced upon deletion of NF-κB, AP-1 or C/EBP binding sites, with NF-κB deletion being the greatest. These results are the first demonstration that IL-1β induces IL-6 production in Müller cells by activation of IL-6 promoter activity predominantly through the p38 MAPK/NF-κB pathway.

New options for uveitis treatment

Uveitis is one of the most important causes of blindness worldwide. Its etiology and pathogenesis are complicated and have not been well understood. The treatment for uveitis is predominantly based on steroids and immunosuppressants. However, systemic side effects limit their clinical application. With the advancement of molecular biology, some intravitreal implants and biologic agents have been used for the treatment of uveitis. Additionally, novel techniques such as gene therapy and RNA interference are being studied for using as uveitis therapy. This paper reviews recent advances in uveitis treatment.

Anti-inflammatory mechanisms of the annexin A1 protein and its mimetic peptide Ac2-26 in models of ocular inflammation in vivo and in vitro

Annexin A1 (AnxA1) is a protein that displays potent anti-inflammatory properties, but its expression in eye tissue and its role in ocular inflammatory diseases have not been well studied. We investigated the mechanism of action and potential uses of AnxA1 and its mimetic peptide (Ac2-26) in the endotoxin-induced uveitis (EIU) rodent model and in human ARPE-19 cells activated by LPS. In rats, analysis of untreated EIU after 24 and 48 h or EIU treated with topical applications or with a single s.c. injection of Ac2-26 revealed the anti-inflammatory actions of Ac2-26 on leukocyte infiltration and on the release of inflammatory mediators; the systemic administration of Boc2, a formylated peptide receptor (fpr) antagonist, abrogated the peptide's protective effects. Moreover, AnxA1(-/-) mice exhibited exacerbated EIU compared with wild-type animals. Immunohistochemical studies of ocular tissue showed a specific AnxA1 posttranslational modification in EIU and indicated that the fpr2 receptor mediated the anti-inflammatory actions of AnxA1. In vitro studies confirmed the roles of AnxA1 and fpr2 and the protective effects of Ac2-26 on the release of chemical mediators in ARPE-19 cells. Molecular analysis of NF-κB translocation and IL-6, IL-8, and cyclooxygenase-2 gene expression indicated that the protective effects of AnxA1 occur independently of the NF-κB signaling pathway and possibly in a posttranscriptional manner. Together, our data highlight the role of AnxA1 in ocular inflammation, especially uveitis, and suggest the use of AnxA1 or its mimetic peptide Ac2-26 as a therapeutic approach.

Cutting-edge issues in autoimmune uveitis

Autoimmune uveitis (AIU) is among the leading causes of preventable blindness. It can be isolated, precede, or appear in the course of a systemic autoimmune inflammatory disease. When suspected, AIU should be promptly referred to an ophthalmologist for proper anatomic classification and local treatment. In recurrent and chronic forms, systemic treatment should be started, usually with corticosteroids and immunesuppressors. In cases of lack of efficacy or intolerance, biologic agents such as monoclonal antibodies anti-TNF (infliximab and adalimumab) and others (abatacept and tocilizumab) are being used. The clinical diseases associated to AIU and the experimental models have helped in the understanding of the pathogenic mechanism. The treatment schemes have improved, and recent advances in basic knowledge are leading to even more effective targeted therapies.

A potential therapeutic role for aldose reductase inhibitors in the treatment of endotoxin-related inflammatory diseases

INTRODUCTION

Aldose reductase (AR) was initially thought to be involved in the secondary diabetic complications because of its glucose-reducing potential. However, evidence from recent studies indicates that AR is an excellent reducer of a number of lipid peroxidation-derived aldehydes as well as their glutathione conjugates, which regulate inflammatory signals initiated by oxidants such as cytokines, growth factors and bacterial endotoxins, and revealed the potential use of AR inhibition as an approach to prevent inflammatory complications.

AREAS COVERED

An extensive Internet and Medline search was performed to retrieve information on understanding the role of AR inhibition in the pathophysiology of endotoxin-mediated inflammatory disorders. Overall, inhibition of AR appears to be a promising strategy for the treatment of endotoxemia, sepsis and other related inflammatory diseases.

EXPERT OPINION

Current knowledge provides enough evidence to indicate that AR inhibition is a logical therapeutic strategy for the treatment of endotoxin-related inflammatory diseases. Since AR inhibitors have already gone to Phase III clinical studies for diabetic complications and found to be safe for human use, their use in endotoxin-related inflammatory diseases could be expedited. However, one of the major challenges will be the discovery of AR-regulated clinically relevant biomarkers to identify susceptible individuals at risk of developing inflammatory diseases, thereby warranting future research in this area.

AAV2-mediated subretinal gene transfer of hIFN-α attenuates experimental autoimmune uveoretinitis in mice

Background

Recent reports show that gene therapy may provide a long-term, safe and effective intervention for human diseases. In this study, we investigated the effectiveness of adeno-associated virus 2 (AAV2) based human interferon-alpha (hIFN-α) gene therapy in experimental autoimmune uveoretinitis (EAU), a classic model for human uveitis.

Methodology/Principal Findings

An AAV2 vector harboring the hIFN-α gene (AAV2.hIFN-α) was subretinally injected into B10RIII mice at two doses (1.5×10⁶ vg, 1.5×10⁸ vg). AAV2 vector encoding green fluorescent protein (AAV2.GFP) was used as a control (5×10⁸ vg). The expression of hIFN-α in homogenized eyes and serum was detected by ELISA three weeks after injection. The biodistribution of vector DNA in the injected eyes, contralateral eyes and distant organs was determined by PCR. EAU was induced by immunization with IRBP_161–180 three weeks following vector injections, and evaluated clinically and pathologically. IRBP-specific proliferation and IL-17 expression of lymphocytes from the spleen and lymph nodes were assayed to test the influence of the subretinal delivery of AAV2.hIFN-α on the systemic immune response. hIFN-α was effectively expressed in the eyes from three weeks to three months following subretinal injection of AAV2.hIFN-α vector. DNA of AAV2.GFP was observed only in the injected eyes, but not in the distant organs or contralateral eyes. Subretinal injection of both doses significantly attenuated EAU activity clinically and histologically. For the lower dose, there was no difference concerning lymphocyte proliferation and IL-17 production among the AAV2.hIFN-α, AAV2.GFP and PBS injected mice. However, the higher dose of AAV2.hIFN-α significantly suppressed lymphocyte proliferation and IL-17 production.

Conclusions/Significance

Subretinal delivery of AAV2.hIFN-α lead to an effective expression within the eye for at least three months and significantly attenuated EAU activity. AAV2.hIFN-α was shown to inhibit the systemic IRBP-specific immune response.

ALDOSE REDUCTASE: New Insights for an Old Enzyme

In the past years aldose reductase (AKR1B1; AR) is thought to be involved in the pathogenesis of secondary diabetic complications such as retinopathy, neuropathy, nephropathy and cataractogenesis. Subsequently, a number of AR inhibitors have been developed and tested for diabetic complications. Although, these inhibitors have found to be safe for human use, they have not been successful at the clinical studies because of limited efficacy. Recently, the potential physiological role of AR has been reassessed from a different point of view. Diverse groups suggested that AR besides reducing glucose, also efficiently reduces oxidative stress-generated lipid peroxidation-derived aldehydes and their glutathione conjugates. Since lipid aldehydes alter cellular signals by regulating the activation of transcription factors such as NF-kB and AP1, inhibition of AR could inhibit such events. Indeed, a wide array of recent experimental evidence indicates that the inhibition of AR prevents oxidative stress-induced activation of NF-kB and AP1 signals that lead to cell death or growth. Further, AR inhibitors have been shown to prevent inflammatory complications such as sepsis, asthma, colon cancer and uveitis in rodent animal models. The new experimental in-vitro and in-vivo data has provided a basis for investigating the clinical efficacy of AR inhibitors in preventing other inflammatory complications than diabetes. This review describes how the recent studies have identified novel plethoric physiological and pathophysiological significance of AR in mediating inflammatory complications, and how the discovery of such new insights for this old enzyme could have considerable importance in envisioning potential new therapeutic strategies for the prevention or treatment of inflammatory diseases.