Hereditary lactate dehydrogenase M-subunit deficiency with late-developing pustular psoriasis-like lesions

Histone Lactylation Participates in Psoriasis Progression by Regulating the Adiponectin Expression

Background

Psoriasis is a chronic inflammatory skin disease characterized by erythema, papules, and plaques. Adiponectin (ADIPOQ) is an important protein hormone secreted by adipose tissue. Here, we aimed to explore the expression of ADIPOQ in psoriasis patients and the moderation effect of histone lactylation on ADIPOQ.

Methods

The GSE78097 data set was downloaded from GEO database to analyze the differentially expressed genes (DEGs) in psoriasis. A total of 36 psoriasis patients were recruited to obtain the skin samples. The ADIPOQ protein levels, global lactylation and histone lactylation (H3K18lac) levels were detected by Western blot assay. Chromatin immunoprecipitation (CHIP) assay was performed to detect the combination between H3K18lac and promoter regions of the ADIPOQ. The receiver operating curve (ROC) analysis was used to evaluate the diagnostic value of ADIPOQ in psoriasis.

Results

ADIPOQ was decreased in the skin tissues of psoriasis patients. In addition, the global lactylation and H3K18lac levels were significantly decreased in the skin tissues of psoriasis patients. In HaCaT cells, promoting the global lactylation and H3K18lac levels increased the ADIPOQ protein levels, while si-LDHA transfection decreased the ADIPOQ protein levels. The CHIP results indicated that lactylation promoted the binding of promoter regions of the ADIPOQ and H3K18lac. Finally, the ROC analysis showed that ADIPOQ exhibited diagnostic value in psoriasis.

Conclusion

This study demonstrated ADIPOQ was decreased in the skin tissues of psoriasis patients, and ADIPOQ has diagnostic value for psoriasis. Furthermore, down-regulation of H3K18lac levels inhibited the transcription of ADIPOQ, which was the key factor of decrease of ADIPOQ levels in psoriasis patients.

Glycogen storage diseases

Glycogen storage diseases (GSDs) are a group of rare, monogenic disorders that share a defect in the synthesis or breakdown of glycogen. This Primer describes the multi-organ clinical features of hepatic GSDs and muscle GSDs, in addition to their epidemiology, biochemistry and mechanisms of disease, diagnosis, management, quality of life and future research directions. Some GSDs have available guidelines for diagnosis and management. Diagnostic considerations include phenotypic characterization, biomarkers, imaging, genetic testing, enzyme activity analysis and histology. Management includes surveillance for development of characteristic disease sequelae, avoidance of fasting in several hepatic GSDs, medically prescribed diets, appropriate exercise regimens and emergency letters. Specific therapeutic interventions are available for some diseases, such as enzyme replacement therapy to correct enzyme deficiency in Pompe disease and SGLT2 inhibitors for neutropenia and neutrophil dysfunction in GSD Ib. Progress in diagnosis, management and definitive therapies affects the natural course and hence morbidity and mortality. The natural history of GSDs is still being described. The quality of life of patients with these conditions varies, and standard sets of patient-centred outcomes have not yet been developed. The landscape of novel therapeutics and GSD clinical trials is vast, and emerging research is discussed herein.

Clinical, Biochemical, and Molecular Characterization of Two Families with Novel Mutations in the LDHA Gene (GSD XI)

Lactate dehydrogenase (LDH) catalyzes the reversible conversion of L-lactate to pyruvate. LDH-A deficiency is an autosomal recessive disorder (glycogenosis type XI, OMIM#612933) caused by mutations in the LDHA gene. We present two young adult female patients presenting with intolerance to anaerobic exercise, episodes of rhabdomyolysis, and, in one of the patients, psoriasis-like dermatitis. We identified in the LDHA gene a homozygous c.410C>A substitution that predicts a p.Ser137Ter nonsense mutation in Patient One and a compound heterozygous c.410C>A (p.Ser137Ter) and c.750G>A (p.Trp250Ter) nonsense mutation in Patient Two. The pathogenicity of the variants was demonstrated by electrophoretic separation of LDH isoenzymes. Moreover, a flat lactate curve on the forearm exercise test, along with the clinical combination of myopathy and psoriatic-like dermatitis, can also lead to the diagnosis.

Establishment of a prediction model for disease progression within one year in newly diagnosed multiple myeloma patients

Multiple myeloma is still an incurable disease In the past decade, with the continuous progress of treatment methods, the progression-free survival of patients has been prolonged, but some patients still progress in the early stage of the disease. Our research analyses the clinical laboratory indicators of newly diagnosed multiple myeloma (NDMM) patients, to obtain the relevant factors of disease progression within one year in MM patients and to establish a prediction model.

108 MM patients treated in our hospital from January 2015 to January 2020 were retrospectively analyzed. After univariate and multivariate logistic regression analyses, the related factors of disease progression within one year in NDMM patients were obtained, and a prediction model was established.

Treatment regimen containing at least two targeted drugs (OR = 0.226, 95% CI 0.068-0.753), increased lactate dehydrogenase(LDH, OR = 3.452, 95% CI 1.101-10.826) and increased serum corrected calcium(OR =  4.466, 95% CI 1.346-14.811) were identified as potential predictors by statistical analysis. The prediction model was obtained: x = -2.042-1.489 × treatment regimen (including at least two targeted drug assignment as 1, otherwise 0) + 1.239 ×LDH (U/L, lactate dehydrogenase elevation assignment as 1, normal as 0) +1.496 × serum corrected calcium (mmol/L, serum corrected calcium elevation assignment as 1, normal as 0). Receiver operating characteristic curve analysis showed that the model has good predictive performance.

The possibility of disease progression within one year can be predicted by the prediction model. The model can be used as a reference for clinicians to make individualized treatment plans for patients so that patients can obtain better treatment effects.

Pustular Psoriasis: From Pathophysiology to Treatment

Pustular psoriasis (PP) is a clinicopathological entity encompassing different variants, i.e., acute generalized PP (GPP), PP of pregnancy (impetigo herpetiformis), annular (and circinate) PP, infantile/juvenile PP, palmoplantar PP/palmoplantar pustulosis, and acrodermatitis continua of Hallopeau (ACH), which have in common an eruption of superficial sterile pustules on an erythematous base. Unlike psoriasis vulgaris, in which a key role is played by the adaptive immune system and interleukin (IL)-17/IL-23 axis, PP seems to be characterized by an intense inflammatory response resulting from innate immunity hyperactivation, with prominent involvement of the IL-36 axis. Some nosological aspects of PP are still controversial and debated. Moreover, owing to the rarity and heterogeneity of PP forms, data on prognosis and therapeutic management are limited. Recent progresses in the identification of genetic mutations and immunological mechanisms have promoted a better understanding of PP pathogenesis and might have important consequences on diagnostic refinement and treatment. In this narrative review, current findings in the pathogenesis, classification, clinical features, and therapeutic management of PP are briefly discussed.

Lactate Metabolism and Signaling in Tuberculosis and Cancer: A Comparative Review

Infection with Mycobacterium tuberculosis (Mtb) leading to tuberculosis (TB) disease continues to be a major global health challenge. Critical barriers, including but not limited to the development of multi-drug resistance, lack of diagnostic assays that detect patients with latent TB, an effective vaccine that prevents Mtb infection, and infectious and non-infectious comorbidities that complicate active TB, continue to hinder progress toward a TB cure. To complement the ongoing development of new antimicrobial drugs, investigators in the field are exploring the value of host-directed therapies (HDTs). This therapeutic strategy targets the host, rather than Mtb, and is intended to augment host responses to infection such that the host is better equipped to prevent or clear infection and resolve chronic inflammation. Metabolic pathways of immune cells have been identified as promising HDT targets as more metabolites and metabolic pathways have shown to play a role in TB pathogenesis and disease progression. Specifically, this review highlights the potential role of lactate as both an immunomodulatory metabolite and a potentially important signaling molecule during the host response to Mtb infection. While long thought to be an inert end product of primarily glucose metabolism, the cancer research field has discovered the importance of lactate in carcinogenesis and resistance to chemotherapeutic drug treatment. Herein, we discuss similarities between the TB granuloma and tumor microenvironments in the context of lactate metabolism and identify key metabolic and signaling pathways that have been shown to play a role in tumor progression but have yet to be explored within the context of TB. Ultimately, lactate metabolism and signaling could be viable HDT targets for TB; however, critical additional research is needed to better understand the role of lactate at the host-pathogen interface during Mtb infection before adopting this HDT strategy.

Hepatic Lactate Dehydrogenase A: An RNA Interference Target for the Treatment of All Known Types of Primary Hyperoxaluria

Introduction

Primary hyperoxaluria (PH) is a family of 3 rare genetic disorders of hepatic glyoxylate metabolism that lead to overproduction and increased renal excretion of oxalate resulting in progressive renal damage. LDHA inhibition of glyoxylate-to-oxalate conversion by RNA interference (RNAi) has emerged as a potential therapeutic option for all types of PH. LDHA is mainly expressed in the liver and muscles.

Methods

Nonclinical data in mice and nonhuman primates show that LDHA inhibition by RNAi reduces urinary oxalate excretion and that its effects are liver-specific without an impact on off-target tissues, such as the muscles. To confirm the lack of unintended effects in humans, we analyzed data from the phase I randomized controlled trial of single-dose nedosiran, an RNAi therapy targeting hepatic LDHA. We conducted a review of the literature on LDHA deficiency in humans, which we used as a baseline to assess the effect of hepatic LDHA inhibition.

Results

Based on a literature review of human LDHA deficiency, we defined the phenotype as mainly muscle-related with no liver manifestations. Healthy volunteers treated with nedosiran experienced no drug-related musculoskeletal adverse events. There were no significant alterations in plasma lactate, pyruvate, or creatine kinase levels in the nedosiran group compared with the placebo group, signaling the uninterrupted interconversion of lactate and pyruvate and normal muscle function.

Conclusion

Phase I clinical data on nedosiran and published nonclinical data together provide substantial evidence that LDHA inhibition is a safe therapeutic mechanism for the treatment of all known types of PH.

Small Molecule-Based Enzyme Inhibitors in the Treatment of Primary Hyperoxalurias

Primary hyperoxalurias (PHs) are a group of inherited alterations of the hepatic glyoxylate metabolism. PHs classification based on gene mutations parallel a variety of enzymatic defects, and all involve the harmful accumulation of calcium oxalate crystals that produce systemic damage. These geographically widespread rare diseases have a deep impact in the life quality of the patients. Until recently, treatments were limited to palliative measures and kidney/liver transplants in the most severe forms. Efforts made to develop pharmacological treatments succeeded with the biotechnological agent lumasiran, a siRNA product against glycolate oxidase, which has become the first effective therapy to treat PH1. However, small molecule drugs have classically been preferred since they benefit from experience and have better pharmacological properties. The development of small molecule inhibitors designed against key enzymes of glyoxylate metabolism is on the focus of research. Enzyme inhibitors are successful and widely used in several diseases and their pharmacokinetic advantages are well known. In PHs, effective enzymatic targets have been determined and characterized for drug design and interesting inhibitory activities have been achieved both in vitro and in vivo. This review describes the most recent advances towards the development of small molecule enzyme inhibitors in the treatment of PHs, introducing the multi-target approach as a more effective and safe therapeutic option.

Reduction in urinary oxalate excretion in mouse models of Primary Hyperoxaluria by RNA interference inhibition of liver lactate dehydrogenase activity

The Primary Hyperoxaluria's (PH) are rare autosomal recessive disorders characterized by elevated oxalate production. PH patients suffer recurrent calcium oxalate kidney stone disease, and in severe cases end stage renal disease. Recent evidence has shown that RNA interference may be a suitable approach to reduce oxalate production in PH patients by knocking down key enzymes involved in hepatic oxalate synthesis. In the current study, wild type mice and mouse models of PH1 (AGT KO) and PH2 (GR KO) were treated with siRNA that targets hepatic LDHA. Although siRNA treatment substantially reduced urinary oxalate excretion [75%] in AGT KO animals, there was a relatively modest reduction [32%] in GR KO animals. Plasma and liver pyruvate levels significantly increased with siRNA treatment and liver organic acid analysis indicated significant changes in a number of glycolytic and TCA cycle metabolites, consistent with the known role of LDHA in metabolism. However, siRNA dosing data suggest that it may be possible to identify a dose that limits changes in liver organic acid levels, while maintaining a desired effect of reducing glyoxylate to oxalate synthesis. These results suggest that RNAi mediated reduction of hepatic LDHA may be an effective strategy to reduce oxalate synthesis in PH, and further analysis of its metabolic effects should be explored. Additional studies should also clarify in GR KO animals whether there are alternate enzymatic pathways in the liver to create oxalate and whether tissues other than liver contribute significantly to oxalate production.

Differential efficacy of biologic treatments targeting the TNF-α/IL-23/IL-17 axis in psoriasis and psoriatic arthritis

Psoriasis and psoriatic arthritis cause significant physical and psychological burdens for afflicted individuals. An accelerated TNF-α/IL-23/IL-17 axis is their major pathomechanism; therefore, anti-TNF-α/IL-23/IL-17 biologics are very effective for the treatment of skin and joint lesions in psoriasis and psoriatic arthritis. Given that the IL-17 signature is more upregulated in the skin than in synovium in psoriatic arthritis, anti-IL-23/IL-17 agents seem to be superior to anti-TNF-α remedies in the treatment of skin lesions. In this review, we focus on the differential efficacy of anti-TNF-α/IL-23/IL-17 biologics in psoriasis and psoriatic arthritis.

Autoimmunity and autoimmune co-morbidities in psoriasis

Psoriasis is characterized by widespread scaly erythematous plaques that cause significant physical and psychological burdens for the affected individuals. Accelerated inflammation driven by the tumour necrosis factor-α/interleukin-23/interleukin-17 axis is now known to be the major mechanism in the development of psoriasis. In addition, psoriasis has an autoimmune nature that manifests as autoreactive T cells and is co-morbid with other autoimmune diseases, such as autoimmune bullous diseases, vitiligo, alopecia and thyroiditis. In this article, we review the recent topics on autoimmunity and autoimmune co-morbidities in psoriasis.