Treatment of psoriasis vulgaris using low-dose naltrexone

Aryl hydrocarbon receptor: current perspectives on key signaling partners and immunoregulatory role in inflammatory diseases

The aryl hydrocarbon receptor (AhR) is a versatile environmental sensor and transcription factor found throughout the body, responding to a wide range of small molecules originating from the environment, our diets, host microbiomes, and internal metabolic processes. Increasing evidence highlights AhR's role as a critical regulator of numerous biological functions, such as cellular differentiation, immune response, metabolism, and even tumor formation. Typically located in the cytoplasm, AhR moves to the nucleus upon activation by an agonist where it partners with either the aryl hydrocarbon receptor nuclear translocator (ARNT) or hypoxia-inducible factor 1β (HIF-1β). This complex then interacts with xenobiotic response elements (XREs) to control the expression of key genes. AhR is notably present in various crucial immune cells, and recent research underscores its significant impact on both innate and adaptive immunity. This review delves into the latest insights on AhR's structure, activating ligands, and its multifaceted roles. We explore the sophisticated molecular pathways through which AhR influences immune and lymphoid cells, emphasizing its emerging importance in managing inflammatory diseases. Furthermore, we discuss the exciting potential of developing targeted therapies that modulate AhR activity, opening new avenues for medical intervention in immune-related conditions.

Influence of phytochemicals in induced psoriasis (Review)

Cytokines involved in pathogenesis of psoriasis such as interleukins (IL-1β, IL-6, IL-17, IL-22, IL-23), interferon-α, tumor necrosis factor-α and interferon-γ can also become therapeutic targets. Research currently uses murine models of imiquimod-induced psoriatic-type dermatitis in order to analyze potentially helpful phytotherapeutics for psoriasis treatment: Curcuma longa, Aloe vera, Nigella sativa, Rubia cordifolia, Smilax china, Thespesia populnea, Wrightia tinctoria, Scutellaria baicalensis, Cassia tora, Pongamia pinnata and various Chinese herbal formulas. Psoriasis is a chronic inflammatory disease with complex pathogenic mechanisms that yield abnormal immune responses with clinical and morphological echoes (erythematous, scaly plaques with a histopathological basis made up of alterations i.e. keratinocyte aberrant proliferation, parakeratosis or chronic inflammation). The current therapeutic approach has only been able to manage the disease, without ensuring a certified treatment, thus giving rise to the need for better medications. This novel therapeutic approach has shown promising results in preclinical studies, giving hope for future phytochemical animal-based studies.

In vitro evaluation of Naltrexone HCl 1% Topical Cream in XemaTop™ for psoriasis

Psoriasis is a multifactorial skin disease involving abnormal cell proliferation and inflammation; an efficacious topical treatment is yet to be identified. A formulation containing 1% Naltrexone HCl in XemaTop™ base was compounded, characterized and evaluated in vitro as a possible treatment for psoriasis. A three-dimensional psoriasis tissue model was exposed to the formulation for 2 or 5 days and analyzed for the level of markers of cellular proliferation, and inflammatory cytokine IL-6. Using immunohistochemical staining, the level of Ki67 protein significantly decreased in the drug-treated tissues. Western blot analysis showed 86% and 53% down-regulation of other proliferation markers PCNA and CYCLIN D1, respectively, after 5-day exposure. The pro-survival Wnt/β-catenin pathway was compromised as indicated by 57% decrease in the level of β-CATENIN and down-regulation of its down-stream targets including CYCLIN D1 (decreased by 53%), c-MYC (63%), c-JUN (92%) and MET (96%) proteins. Likewise, the PI3K/AKT/mTOR pathway was significantly inhibited by 1% Naltrexone HCl in XemaTop™, suggesting protein synthesis was affected. The production of IL-6 was inhibited by 70% in drug-treated tissues. These results suggest that the compounded drug is efficacious in down-regulating molecular markers associated with the pathogenesis of psoriasis. Low-dose Naltrexone in XemaTop™ was stable within 180 days when stored under refrigerated or ambient conditions. These results provide a basis for a clinical evaluation of 1% Naltrexone HCl in XemaTop™ in psoriasis patients.

The Use of Naltrexone in Dermatology. Current Evidence and Future Directions

Naltrexone is a competitive opioid receptor antagonist approved as supportive treatment in alcohol dependence and opioid addiction. At a dose of 50-100 mg daily, naltrexone is used off-label in dermatology for the treatment of trichotillomania and different types of pruritus. At a dose as low as 1- 5 mg per day, naltrexone demonstrates immunomodulatory action i.e. modulates Toll-like receptors signaling, decreases release of proinflammatory cytokines (tumor necrosis factor, interleukin-6, interleukin- 12), inhibits T lymphocyte proliferation, down-regulates the expression of chemokine receptors and adhesion molecules. The efficacy of standard and low doses of naltrexone in a variety of dermatological disorders has been reported. These include diseases such as familial benign chronic pemphigus (Hailey-Hailey disease), dermatomyositis, systemic sclerosis, psoriasis and lichen planopilaris. Optimistic preliminary findings, low cost of therapy and good tolerance make naltrexone a promising alternative therapy or adjunct drug in dermatology.

Low dose naltrexone: Effects on medication in rheumatoid and seropositive arthritis. A nationwide register-based controlled quasi-experimental before-after study

In recent years, low dose naltrexone (LDN) has been used as an off-label therapy for several chronic diseases. Results from small laboratory and clinical studies indicate some beneficial effects of LDN in autoimmune diseases, but clinical research on LDN in rheumatic disease is limited. Using a pharmacoepidemiological approach, we wanted to test the hypothesis that starting LDN leads to reduced dispensing of medicines used in the treatment of rheumatic disease. We performed a controlled before-after study based on the Norwegian Prescription Database (NorPD) to compare prescriptions to patients one year before and one year after starting LDN in 2013. The identified patients (n = 360) were stratified into three groups based on LDN exposure. Outcomes were differences in dispensing of medicines used in rheumatic disease. In persistent LDN users, there was a 13% relative reduction in cumulative defined daily doses (DDD) of all medicines examined corresponding to -73.3 DDD per patient (95% CI -120,2 to -26.4, p = 0.003), and 23% reduction of analgesics (-21.6 DDD (95% CI -35.5 to -7.6, p<0.009)). There was no significant DDD change in patients with lower LDN exposure. Persistent LDN users had significantly reduced DDDs of NSAID and opioids, and a lower proportion of users of DMARDs (-6.7 percentage points, 95% CI -12.3 to-1.0, p = 0.028), TNF-α antagonists and opioids. There was a decrease in the number of NSAID users among patients with the least LDN exposure. Important limitations are that prescription data are proxies for clinical effects and that a control group unexposed to LDN is lacking. The results support the hypothesis that persistent use of LDN reduces the need for medication used in the treatment of rheumatic and seropositive arthritis. Randomised clinical trials on LDN in rheumatic disease are warranted.

Low-dose Naltrexone: An Alternative Treatment for Erythrodermic Psoriasis

This clinical case demonstrates the benefits of patient treatment with low-dose naltrexone (LDN) used in erythrodermic psoriasis. A patient with a confirmed history of psoriasis by histopathology was treated with 4.5 mg of LDN during six months follow-up after an erythrodermic psoriasis flare-up. The patient showed significant improvement in her flare-up and psoriasis remission after only three months of 4.5 mg of LDN on a daily basis. Low-dose naltrexone (LDN) has proven to be a great ally in treating erythrodermic psoriasis flare-ups as an alternative treatment with less collateral side effects.

The Role of the Aryl Hydrocarbon Receptor (AHR) in Immune and Inflammatory Diseases

The aryl hydrocarbon receptor (AHR) is a nuclear receptor that modulates the response to environmental stimuli. It was recognized historically for its role in toxicology but, in recent decades, it has been increasingly recognized as an important modulator of disease—especially for its role in modulating immune and inflammatory responses. AHR has been implicated in many diseases that are driven by immune/inflammatory processes, including major depressive disorder, multiple sclerosis, rheumatoid arthritis, asthma, and allergic responses, among others. The mechanisms by which AHR has been suggested to impact immune/inflammatory diseases include targeted gene expression and altered immune differentiation. It has been suggested that single nucleotide polymorphisms (SNPs) that are near AHR-regulated genes may contribute to AHR-dependent disease mechanisms/pathways. Further, we have found that SNPs that are outside of nuclear receptor binding sites (i.e., outside of AHR response elements (AHREs)) may contribute to AHR-dependent gene regulation in a SNP- and ligand-dependent manner. This review will discuss the evidence and mechanisms of AHR contributions to immune/inflammatory diseases and will consider the possibility that SNPs that are outside of AHR binding sites might contribute to AHR ligand-dependent inter-individual variation in disease pathophysiology and response to pharmacotherapeutics.