Expression of sirtuins 1, 6, tumor necrosis factor, and interferon-γ in psoriatic patients

Histone modification in psoriasis: Molecular mechanisms and potential therapeutic targets

Psoriasis is an immune-mediated, inflammatory disease. Genetic and environmental elements are involved in the nosogenesis of this illness. Epigenetic inheritance serves as the connection between genetic and environmental factors. Histone modification, an epigenetic regulatory mechanism, is implicated in the development of numerous diseases. The basic function of histone modification is to regulate cellular functions by modifying gene expression. Modulation of histone modification, such as regulation of enzymes pertinent to histone modification, can be an alternative approach for treating some diseases, including psoriasis. Herein, we reviewed the regulatory mechanisms and biological effects of histone modifications and their roles in the pathogenesis of psoriasis.

Genome-wide DNA methylation of lesional and peri-lesional skin in vitiligo: a comparative and integrated analysis of multi-omics in Chinese population

Several studies have emphasized the role of DNA methylation in vitiligo. However, its profile in human skin of individuals with vitiligo remains unknown. Here, we aimed to study the DNA methylation profile of vitiligo using pairwise comparisons of lesions, peri-lesions, and healthy skin. We investigated DNA methylation levels in six lesional skin, six peri-lesional skin, and eight healthy skin samples using an Illumina 850 K methylation chip. We then integrated DNA methylation data with transcriptome data to identify differentially methylated and expressed genes (DMEGs) and analyzed their functional enrichment. Subsequently, we compared the methylation and transcriptome characteristics of all skin samples, and the related genes were further studied using scRNA-seq data. Finally, validation was performed using an external dataset. We observed more DNA hypomethylated sites in patients with vitiligo. Further integrated analysis identified 264 DMEGs that were mainly functionally enriched in cell division, pigmentation, circadian rhythm, fatty acid metabolism, peroxidase activity, synapse regulation, and extracellular matrix. In addition, in the peri-lesional skin, we found that methylation levels of 102 DMEGs differed prior to changes in their transcription levels and identified 16 key pre-DMEGs (ANLN, CDCA3, CENPA, DEPDC1, ECT2, DEPDC1B, HMMR, KIF18A, KIF18B, TTK, KIF23, DCT, EDNRB, MITF, OCA2, and TYRP1). Single-cell RNA analysis showed that these genes were associated with cycling keratinocytes and melanocytes. Further analysis of cellular communication indicated the involvement of the extracellular matrix. The expression of related genes was verified using an external dataset. To the best of our knowledge, this is the first study to report a comprehensive DNA methylation profile of clinical vitiligo and peri-lesional skin. These findings would contribute to future research on the pathogenesis of vitiligo and potential therapeutic strategies.

Noval advance of histone modification in inflammatory skin diseases and related treatment methods

Inflammatory skin diseases are a group of diseases caused by the disruption of skin tissue due to immune system disorders. Histone modification plays a pivotal role in the pathogenesis and treatment of chronic inflammatory skin diseases, encompassing a wide range of conditions, including psoriasis, atopic dermatitis, lupus, systemic sclerosis, contact dermatitis, lichen planus, and alopecia areata. Analyzing histone modification as a significant epigenetic regulatory approach holds great promise for advancing our understanding and managing these complex disorders. Additionally, therapeutic interventions targeting histone modifications have emerged as promising strategies for effectively managing inflammatory skin disorders. This comprehensive review provides an overview of the diverse types of histone modification. We discuss the intricate association between histone modification and prevalent chronic inflammatory skin diseases. We also review current and potential therapeutic approaches that revolve around modulating histone modifications. Finally, we investigated the prospects of research on histone modifications in the context of chronic inflammatory skin diseases, paving the way for innovative therapeutic interventions and improved patient outcomes.

The role of glucose-dependent insulinotropic polypeptide 3 (G1P-3) and nucleolar phosphoprotein-1 (NPM1) in pathogenesis of psoriasis

Background Psoriasis is a multifactorial, hyperproliferative, chronic inflammatory skin disease affecting males and females equally. Aims To study the expression of certain non-coding RNAs, Interferon Alpha Inducible Protein 6 (IFI6), previously named Glucose-dependent Insulinotropic Polypeptide 3 (G1P-3), and nucleolar phosphoprotein (in serum and tissue), and to attempt to elucidate their role in the pathogenesis of psoriasis, which in turn might help in treatment. Methods Twenty patients with psoriasis and 20 healthy subjects were included in this study. Serum and skin biopsies were obtained from all participants. Molecular biology techniques were employed to estimate the expression levels of long noncoding G1P-3 and nucleolar phosphoprotein in serum and skin biopsy. Results Psoriasis patients had a mean age of 41.85 ± 12.29. The median serum G1P-3 level of the patients' group (3.330) was significantly higher than that of the control group (1.085) (P ≤ 0.001). Tissue G1P-3 level of the patients' group (6.495) was also significantly higher compared to that of controls (1.040) (P ≤ 0.001). Similarly, for nucleolar phosphoprotein, the median serum level of patients' group (2.030) was significantly higher than that of controls (1.040) (P ≤ 0.001) and median tissue level (5.425) was also significantly higher than that of controls (1.040) (P ≤ 0.001). Limitations In this study, only outpatients were included and follow-up was not well-handled. For future work, follow-up can be considered. Conclusion Long non-coding G1P-3 as well as nucleolar phosphoprotein may be considered as genetic markers for psoriasis susceptibility. In future, these might provide a novel direction for advances in psoriasis treatment.

CircVAPA contributes to hyper-proliferation and inflammation of keratinocytes through miR-125b-5p/sirt6 axis in psoriasis

Psoriasis is an autoimmune skin disease with abnormal keratinocyte hyperproliferation. The important roles of circular RNAs (circRNAs) in various inflammatory diseases have been revealed. The present study aimed to investigate the roles of circVAPA and its molecular mechanisms in psoriasis. Quantitative real-time polymerase chain reaction was performed to measure the RNA expression. Enzyme-linked immunosorbent assays were employed to examine the production of inflammatory factors. Cell-counting kit-8, EDU and flow cytometry assay were conducted to examine the cell viability, proliferation and apoptosis respectively. Dual-luciferase reporter assay and ribonucleoprotein immunoprecipitation (RIP) were conducted to verify the target relationship between miR-125b-5p and circVAPA or Sirt6. Herein our findings showed increased expression of circVAPA and Sirt6 and decreased level of miR-125b-5p in psoriatic lesional tissues and M5-stimulated keratinocytes. Mechanistically, circVAPA knockdown significantly suppressed the promotion of M5 on cell viability, proliferation, and inflammation of HaCaT cells. circVAPA was verified to interact with miR-125b-5p, while inhibition of miR-125b-5p counteracted circVAPA knockdown-mediated effects in M5-stimulated HaCaT cells. Sirt6 was confirmed as a target of miR-125b-5p, and miR-125b-5p overexpression inhibited cell growth and inflammation partly by targeting Sirt6 in M5-stimulated HaCaT cells. Moreover, circVAPA was featured as a competing endogenous RNA by directly sponging miR-125b-5p to up-regulate the expression of Sirt6. CircVAPA participate in the progression of psoriasis through miR-125b-5p/sirt6 axis by regulating proliferation and inflammation of keratinocytes, highlighting a potential therapeutic target for psoriasis.

Participation of interferons in psoriatic inflammation

Interferons are multifunctional cytokines not expressed in the skin under normal physiological conditions. However, they are overexpressed in serum and skin lesions of patients with psoriasis and play an important role in the pathogenesis of the disease. Interferons act directly on skin resident cells and recruit and modulate inflammatory cells, thereby exacerbating psoriatic inflammation. They upregulate the expression of relevant cytokines and chemokines, facilitate excessive proliferation of keratinocytes, and enhance the formation of poorly differentiated dermal microvessels. In this review, we summarized the pathogenic effect of interferons on psoriasis and also discussed the therapeutic strategies targeting interferons.

The role of LncRNA MALAT-1 and MiRNA-9 in Psoriasis

Background

Psoriasis is a chronic skin disorder manifested by recurrent episodes of scaly, red, itchy skin patches that occur within apparently normal skin.

Objectives

This study was performed to detect the expression of serum and tissue (lesion and non-lesion) LncRNA MALAT-1 and MiRNA-9 that might be used as biomarkers for psoriasis.

Methods

Blood samples were obtained from 60 psoriasis patients and 40 controls, as well as 4 mm punch biopsy from lesional and non lesional skin of psoriatic patient and normal skin of healthy controls. Expression of LncRNA MALAT-1 and miRNNA-9 in serum and tissues was detected by real time qRT-PCR.

Results

a statistically significant increase in the expression of MALAT-1 in lesional and non-lesional skin and serum of psoriatic patients in comparison to controls were detected. Moreover, there was statistically significant increase in serum MiRNA-9 in patients in comparison to controls, while its tissue level was significantly lower in patients.

Conclusion

This study highlights the dysregulation of LncRNA MALAT-1 and miRNA-9 in psoriasis. Elevated expression of MALAT-1 in lesional skin of psoriatic patients compared to non-lesional skin may possibly contribute to the development of psoriatic plaques.

Role of Epigenetics in the Regulation of Immune Functions of the Skin

This review is intended to illuminate the emerging understanding of epigenetic modifications that regulate both adaptive and innate immunity in the skin. Host defense of the epidermis and dermis involves the interplay of many cell types to enable homeostasis; tolerance to the external environment; and appropriate response to transient microbial, chemical, and physical insults. To understand this process, the study of cutaneous immunology has focused on immune responses that reflect both adaptive learned and genetically programmed innate defense systems. However, recent advances have begun to reveal that epigenetic modifications of chromatin structure also have a major influence on the skin immune system. This deeper understanding of how enzymatic changes in chromatin structure can modify the skin immune system and may explain how environmental exposures during life, and the microbiome, lead to both short-term and long-term changes in cutaneous allergic and other inflammatory processes. Understanding the mechanisms responsible for alterations in gene and chromatin structure within skin immunocytes could provide key insights into the pathogenesis of inflammatory skin diseases that have thus far evaded understanding by dermatologists.

Oxidative Stress as an Important Contributor to the Pathogenesis of Psoriasis

This review discusses how oxidative stress (OS), an imbalance between oxidants and antioxidants in favor of the oxidants, increased production of reactive oxygen species (ROS)/reactive nitrogen species (RNS), and decreased concentration/activity of antioxidants affect the pathogenesis or cause the enhancement of psoriasis (Ps). Here, we also consider how ROS/RNS-induced stress modulates the activity of transcriptional factors and regulates numerous protein kinase cascades that participate in the regulation of crosstalk between autophagy, apoptosis, and regeneration. Answers to these questions will likely uncover novel strategies for the treatment of Ps. Action in the field will avoid destructive effects of ROS/RNS-mediated OS resulting in cellular dysfunction and cell death. The combination of the fragmentary information on the role of OS can provide evidence to extend the full picture of Ps.

Effect of adalimumab on the expression profile of mRNA, and protein associated with JAK/STAT signaling pathway in fibroblast exposed to lipopolysaccharide

The aim of this study was to assess the effect of adalimumab on the expression level of mRNA and protein TNF-α, IFN-γ, IL-17, IL12A, IL12B, and IL23A in the culture of normal human fibroblasts, in which the LPS inflammation process was induced. The NHDF culture was exposed to the effect of LPS in the concentrations of 1, 2, and 10 μg/mL for 2, 8, and 24 hour periods, and then adalimumab was added at the concentration of 8 μg/mL, it was then incubated for 2, 8, and 24 hour. Cells unexposed to LPS and adalimumab constituted the control. The microarray expression techniques, RTqPCR, and ELISA assay were used. Irrespectively of the concentration of LPS used and the incubation time of it with cells overexpression of the analyzed genes is present, with increasing factor concentration used to induce inflammation and incubation time with it, expression of the assessed genes was greater. In turn, adding the anti-TNF drug to the culture caused the silencing of the expression of the mRNAs and proteins. It was confirmed that LPS and adalimumab above all affect the expression of genes and proteins dependent on the interaction of IL-12 with receptors, which are TNF-α and IFN-γ, and to a lesser extent also modulate IL-17.

Evaluation of expression pattern of selected genes associated with IL12/23 signaling paths in psoriatic patients during cyclosporine A therapy

Molecular analysis is key to a better understanding of drug resistance during therapy. The aim of this study was to evaluate changes in the expression of tumor necrosis factor α (TNF-α), interleukin (IL)-IL12A, IL12B, IL23A, interferon gamma (IFN-γ) in psoriatic patients during 84 days of treatment and TNF-α on the protein level. The study group consisted of 32 psoriatic patients during cyclosporine A therapy. The molecular analysis was made by using real-time reverse transcription polymerase chain assay (RTqPCR) and MALDI ToF mass spectroscopy three times: after 0, 42, 84 days of treatment. Statistically significant differences (p < .05) in transcriptional activity were observed for genes: TNF-α (0 vs. 42nd days p = .006; 0 vs. 84th days p = .005), IL23A (0 vs. 42nd days p = .041), IFN-γ (0 vs. 42th days p = .040; 0 vs. 84th days p = .041), IL17 (0 vs. 42nd p = .000003 0 vs. 84th p = .001650), IL12A (0 vs. 42nd p = .0047 vs. 84th p = .0063). The expression of TNF-α was downregulated during therapy, IL23A was upregulated during CsA treatment, while the expression of IFN-γ and IL17 were higher after 42 days and lower after 84 days compared to 0 days of CsA treatment. It seems that TNF-α, IL12A, IL23A, IFN-γ, and IL17 can be useful complementary molecular markers to assess the efficacy of psoriasis treatment.

Abnormal expression of SIRTs in psoriasis: Decreased expression of SIRT 1-5 and increased expression of SIRT 6 and 7

The prevalence of psoriasis is increasing, and poses a serious risk to human health and quality of life. Psoriasis, a chronic immune‑mediated skin disease with epidermal hyperkeratosis and parakeratosis, is associated with numerous complications, including metabolic syndromes that are regulated by sirtuins (SIRTs) via deacetylation. As they serve a necessary function in inflammation and metabolism, SIRTs are considered to link inflammation and metabolic syndrome. Previous studies have indicated that SIRTs serve a function in the pathophysiology of psoriasis, but to date no detailed research has been conducted investigating the expression levels and patterns of SIRTs in psoriasis. The present study investigated the abnormal expression of SIRTs in psoriasis and provided a theoretical foundation for the treatment and prognosis of psoriasis. Tumor necrosis factor (TNF)‑α‑stimulated HaCaT cells and an imiquimod‑induced psoriasis mouse model were used to produce in vitro and in vivo models, respectively. Psoriasis clinical specimens (psoriasis area and severity index >10; n=22) and normal group specimens (n=22) were obtained from human subjects. The mRNA and protein expression levels in human and mouse skin lesions and TNF‑α‑stimulated HaCaT cells were detected using reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) and western blotting, and compared with the control groups. The expression patterns of SIRT proteins were investigated using immunofluorescence (IF) staining. The expression levels of SIRT1, SIRT2, SIRT3, SIRT4 and SIRT5 were downregulated while those of SIRT6 and SIRT7 were upregulated in skin lesions and TNF‑α‑stimulated HaCaT cells compared with the control group as determined by RT‑qPCR, western blotting and IF. Statistically significant differences were observed in vivo and in vitro. P‑values of SIRT1‑7 mRNA are less than 0.05 in RT‑qPCR, and the P‑values of SIRT1‑7 proteins are less than 0.05 except for SIRT4 in the western blot analysis. SIRTs serve notable functions in severe psoriasis dermatitis, with the overexpression of SIRT6 and SIRT7 potentially induced by the adaptive immune response, and the downregulation of SIRT1, SIRT2, SIRT3, SIRT4 and SIRT5 may be a result of an internal environment imbalance in vivo. Psoriasis is an inflammation and metabolism‑associated disease mediated by the SIRT family. The present results provide a novel potential mechanism and strategy for the treatment of psoriasis by modulating the function and expression of SIRTs.

Decreased A-to-I RNA editing as a source of keratinocytes' dsRNA in psoriasis

Recognition of dsRNA molecules activates the MDA5-MAVS pathway and plays a critical role in stimulating type-I interferon responses in psoriasis. However, the source of the dsRNA accumulation in psoriatic keratinocytes remains largely unknown. A-to-I RNA editing is a common co- or post-transcriptional modification that diversifies adenosine in dsRNA, and leads to unwinding of dsRNA structures. Thus, impaired RNA editing activity can result in an increased load of endogenous dsRNAs. Here we provide a transcriptome-wide analysis of RNA editing across dozens of psoriasis patients, and we demonstrate a global editing reduction in psoriatic lesions. In addition to the global alteration, we also detect editing changes in functional recoding sites located in the IGFBP7, COPA, and FLNA genes. Accretion of dsRNA activates autoimmune responses, and therefore the results presented here, linking for the first time an autoimmune disease to reduction in global editing level, are relevant to a wide range of autoimmune diseases.

Sirt1 Protects against Oxidative Stress-Induced Apoptosis in Fibroblasts from Psoriatic Patients: A New Insight into the Pathogenetic Mechanisms of Psoriasis

Psoriasis, a multisystem chronic disease characterized by abnormal keratinocyte proliferation, has an unclear pathogenesis where systemic inflammation and oxidative stress play mutual roles. Dermal fibroblasts, which are known to provide a crucial microenvironment for epidermal keratinocyte function, represented the selected experimental model in our study which aimed to clarify the potential role of SIRT1 in the pathogenetic mechanisms of the disease. We firstly detected the presence of oxidative stress (lipid peroxidation and total antioxidant capacity), significantly reduced SIRT1 expression level and activity, mitochondrial damage and apoptosis (caspase-3, -8 and -9 activities) in psoriatic fibroblasts. Upon SIRT1 activation, redox balance was re-established, mitochondrial function was restored and apoptosis was no longer evident. Furthermore, we examined p38, ERK and JNK activation, which was strongly altered in psoriatic fibroblasts, in response to SIRT1 activation and we measured caspase-3 activity in the presence of specific MAPK inhibitors demonstrating the key role of the SIRT1 pathway against apoptotic cell death via MAPK modulation. Our results clearly demonstrate the involvement of SIRT1 in the protective mechanisms related to fibroblast injury in psoriasis. SIRT1 activation exerts an active role in restoring both mitochondrial function and redox balance via modulation of MAPK signaling. Hence, SIRT1 can be proposed as a specific tool for the treatment of psoriasis.

Genetic and serum biomarker evidence for a relationship between TNFα and PTSD in Vietnam war combat veterans

BACKGROUND

Posttraumatic stress disorder (PTSD) is associated with increased inflammation and comorbid medical conditions. However, study findings for individual inflammatory marker levels have been inconsistent. Some research suggests that resilience may play a role in decreased inflammation. A polymorphism in the promoter region of the tumor necrosis factor α gene (TNFα), TNFA -308 (rs1800629) is associated with psychiatric illness but its role in PTSD is yet to be elucidated.

OBJECTIVE

This study investigates a key inflammatory marker, TNFα, for its role in PTSD severity.

METHOD

In a cohort of trauma-exposed Vietnam War veterans (n=299; 159 cases, 140 controls) TNF α serum levels and TNFα polymorphism rs1800629 were correlated with PTSD severity and resilience scores.

RESULTS

The polymorphism was associated with PTSD severity (p=0.045). There were significant group differences between cases and controls with regards to serum TNFα levels (p=0.036). Significant correlations were found between PTSD severity and elevated TNFα levels (r=0.153; p=0.009), and between resilience and decreased TNFα levels at a trend level (p=0.08) across the entire cohort. These relationships were non-significant after controlling for covariates. In the PTSD diagnostic group, a correlation of TNFα and PTSD severity was observed on a trend level (p=0.06), the relationship between TNFα and resilience remained non-significant.

CONCLUSIONS

To our knowledge, this is the first time rs1800629 has been investigated in PTSD contributing to a growing body of literature that identifies the GG as a risk genotype for psychiatric disorders in Caucasian cohorts. However, more research is needed to replicate our results in larger, equally well-characterized cohorts. The relationship between serum TNFα levels and PTSD severity and resilience requires further investigation.