HR-MS Based Untargeted Lipidomics Reveals Characteristic Lipid Signatures of Wilson's Disease

Allergic inflammation triggers dyslipidemia via IgG signalling

BACKGROUND

Allergic diseases begin early in life and are often chronic, thus creating an inflammatory environment that may precede or exacerbate other pathologies. In this regard, allergy has been associated to metabolic disorders and with a higher risk of cardiovascular disease, but the underlying mechanisms remain incompletely understood.

METHODS

We used a murine model of allergy and atherosclerosis, different diets and sensitization methods, and cell-depleting strategies to ascertain the contribution of acute and late phase inflammation to dyslipidemia. Untargeted lipidomic analyses were applied to define the lipid fingerprint of allergic inflammation at different phases of allergic pathology. Expression of genes related to lipid metabolism was assessed in liver and adipose tissue at different times post-allergen challenge. Also, changes in serum triglycerides (TGs) were evaluated in a group of 59 patients ≥14 days after the onset of an allergic reaction.

RESULTS

We found that allergic inflammation induces a unique lipid signature that is characterized by increased serum TGs and changes in the expression of genes related to lipid metabolism in liver and adipose tissue. Alterations in blood TGs following an allergic reaction are independent of T-cell-driven late phase inflammation. On the contrary, the IgG-mediated alternative pathway of anaphylaxis is sufficient to induce a TG increase and a unique lipid profile. Lastly, we demonstrated an increase in serum TGs in 59 patients after undergoing an allergic reaction.

CONCLUSION

Overall, this study reveals that IgG-mediated allergic inflammation regulates lipid metabolism.

Effects of dietary copper intake on blood lipids in women of childbearing age and the potential role of gut microbiota

Background

Copper (Cu) is a vital trace element involved in numerous physiological processes, including glycolysis and lipid metabolism. Imbalances in Cu homeostasis can contribute to various diseases. However, current research on the impact of Cu on lipid metabolism has yielded inconsistent findings. Moreover, studies investigating the effects of dietary Cu intake on blood lipids among women of childbearing age are rare. Understanding of this relationship could enhance lipid management, given that most women obtain Cu through their diet. Additionally, the gut microbiota may play a role in this process. This study aims to investigate the effects of dietary Cu intake on blood lipids in women of childbearing age and to analyze the role of gut microbiota in this process.

Methods

This study utilized data from the National Health and Nutrition Examination Survey (NHANES) to conduct a preliminary analysis of the correlation between dietary Cu levels and blood lipid indicators in women of childbearing age. Subsequently, an on-site research was conducted to further investigate this relationship, followed by animal experiments to verify the effect of different Cu doses on blood lipid levels. Multiple linear regression models, ANOVA, XGBOOST were employed to analyze the impact of Cu on blood lipids and the role of intestinal microbiota in this process.

Results

In the population study, the NHANES results were consistent with on-site findings. The TG, and TC levels in women with childbearing were increased with higher dietary Cu intake. Animal experiments have shown that as Cu intake increases, TC levels increase. Furthermore, when the Cu intake reached 8 mg/day (the recommended dietary Cu intake limit of China, RDI), the TG levels in the research animals decrease, alongside a reduction in the abundance of Weissella cibaria (probiotics related to lipid metabolism), and the levels of LPS and IL-6 increase.

Conclusion

The blood lipid levels of women of childbearing age increase with higher dietary Cu intake. RDI of 8 mg/day for women of childbearing age in China may need to be appropriately reduced. Regulating the gut microbiota, especially by increasing the abundance of Weissella cibaria may be an effective intervention for blood lipids.

Hepatic oxylipin profiles in mouse models of Wilson disease: New insights into early hepatic manifestations

Hepatic inflammation is commonly identified in Wilson disease (WD), a genetic disease of hepatic and brain copper accumulation. Copper accumulation is associated with increased oxidative stress and reactive oxygen species generation which may result in non-enzymatic oxidation of membrane-bound polyunsaturated fatty acids (PUFA). PUFA can be oxidized enzymatically via lipoxygenases (LOX), cyclooxygenases (COX), and cytochrome P450 monooxygenases (CYP). Products of PUFA oxidation are collectively known as oxylipins (OXL) and are bioactive lipids that modulate hepatic inflammation. We examined hepatic OXL profiles at early stages of WD in two mouse models, the toxic milk mouse from The Jackson Laboratory (tx-j) and the Atp7b knockout on a C57Bl/6 background (Atp7b-/-B6). Targeted lipidomic analysis performed by ultra-high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry showed that in both tx-j and Atp7b-/-B6 mice, hepatic OXL profiles were altered with higher thromboxane and prostaglandins levels. The levels of oxidative stress marker, 9-HETE were increased more markedly in tx-j mice. However, both genotypes showed upregulated transcript levels of many genes related to oxidative stress and inflammation. Both genotypes showed higher prostaglandins, thromboxin along with higher PUFA-derived alcohols, diols, and ketones with altered epoxides; the expression of Alox5 was upregulated and many CYP-related genes were dysregulated. Pathway analyses show dysregulation in arachidonic acid and linoleic acid metabolism characterizes mice with WD. Our findings indicate alterations in hepatic PUFA metabolism in early-stage WD and suggest the upregulation of both, non-enzymatic ROS-dependent and enzymatic PUFA oxidation, which could have implications for hepatic manifestations in WD and represent potential targets for future therapies.

A case of Wilson's disease combined with intracranial lipoma and dysplasia of the corpus callosum with review of the literature

BACKGROUND

Wilson's disease (WD) is an inherited disorder of copper metabolism. Agenesis of the corpus callosum is the complete or partial absence of the major united fiber bundles connecting the cerebral hemispheres. Intracranial lipoma is an adipose tissue tumor resulting from an abnormal embryonic development of the central nervous system. The simultaneous occurrence of these three disorders is rare and has not been reported. This report focuses on the pathogenesis and association between the three disorders and highlights the importance of recognizing and effectively managing their coexistence.

CASE PRESENTATION

The purpose of this study was to present a patient with coexisting WD, intracranial lipoma, and corpus callosum dysplasia. We reviewed a female patient hospitalized in 2023 with clinical manifestations of elevated aminotransferases and decreased ceruloplasmin, as well as genetic testing for an initial diagnosis of Wilson's disease. Subsequently, a cranial MRI showed corpus callosum dysplasia with short T1 signal changes in the cerebral falx, leading to a final diagnosis of Wilson's disease combined with intracranial lipoma and corpus callosum dysplasia. The patient's WD is currently stable after treatment with sodium dimercaptosulfonamide (DMPS) and penicillamine, and the patient's abnormal copper metabolism may promote the growth of intracranial lipoma.

CONCLUSION

The pathogenesis of WD combined with intracranial lipoma and corpus callosum dysplasia is complex and clinically rare. The growth of intracranial lipomas may be associated with abnormal copper metabolism in WD. Abnormal copper metabolism affects lipid metabolism and triggers inflammatory responses. Therefore, early diagnosis and treatment are beneficial for improvement. Each new case of this rare co-morbidity is important as it allows for a better assessment and understanding of these cases' more characteristic clinical manifestations, which can help estimate the course of the disease and possible therapeutic options.

The role of intestine in metabolic dysregulation in murine Wilson disease

BACKGROUND

The clinical manifestations of Wilson disease (WD) are related to copper accumulation in the liver and the brain, but little is known about other tissue involvement regarding metabolic changes in WD. In vitro studies suggested that the loss of intestinal ATP7B affects metabolic dysregulation in WD. We tested this hypothesis by evaluating the gut microbiota and lipidome in 2 mouse models of WD and by characterizing a new mouse model with a targeted deletion of Atp7b in the intestine.

METHODS

Cecal content 16S sequencing and untargeted hepatic and plasma lipidome analyses in the Jackson Laboratory toxic-milk and the Atp7b null global knockout mouse models of WD were profiled and integrated. Intestine-specific Atp7b knockout mice (Atp7bΔIEC) were generated and characterized using targeted lipidome analysis following a high-fat diet challenge.

RESULTS

Gut microbiota diversity was reduced in animal models of WD. Comparative prediction analysis revealed amino acid, carbohydrate, and lipid metabolism functions to be dysregulated in the WD gut microbial metagenome. Liver and plasma lipidomic profiles showed dysregulated triglyceride and diglyceride, phospholipid, and sphingolipid metabolism in WD models. However, Atp7bΔIEC mice did not show gut microbiome differences compared to wild type. When challenged with a high-fat diet, Atp7bΔIEC mice exhibited profound alterations to fatty acid desaturation and sphingolipid metabolism pathways as well as altered APOB48 distribution in intestinal epithelial cells.

CONCLUSIONS

Gut microbiome and lipidome underlie systemic metabolic manifestations in murine WD. Intestine-specific ATP7B deficiency affected both intestinal and systemic response to a high-fat challenge but not the microbiome profile, at least at early stages. WD is a systemic disease in which intestinal-specific ATP7B loss and diet influence the phenotype and the lipidome profile.

Features of the response to subchronic low-dose exposure to copper oxide nanoparticles in rats

Copper is an essential trace element for human health and, at the same time, a major industrial metal widely used both in its elemental form and in compounds. We conducted a dose-dependent assessment of the response of outbred albino male rats to subchronic low-dose exposure to copper oxide nanoparticles administered intraperitoneally at cumulative doses of 18 and 36 mg/kg during 6 weeks to exposure groups 1 and 2, respectively. We observed disorders at different levels of organization of the body in the exposed animals, from molecular to organismal. The observed decrease in the activity of succinate dehydrogenase in nucleated blood cells gave evidence of impaired bioenergetics processes. In view of the results of the metabolomics analysis, we assume mitochondrial damage and contribution of apoptotic processes to the pathology induced by copper poisoning. We also assume neurodegenerative effects based on the assessed morphological parameters of the nervous system, results of behavioral tests, and a decreased level of expression of genes encoding NMDA receptor subunits in the hippocampus. The hepatotoxic effect noted by a number of metabolomics-based, biochemical, and cytological indicators was manifested by the impaired protein-synthesizing function of the liver and enhanced degenerative processes in its cells. We also observed a nephrotoxic effect of nanosized copper oxide with a predominant lesion of proximal kidney tubules. At the same time, both doses tested demonstrated such positive health effects as a statistically significant decrease in the activity of alkaline phosphatase and the nucleated blood cell DNA fragmentation factor. Judging by the changes observed, the cumulative dose of copper oxide nanoparticles of 18 mg/kg body weight administered intraperitoneally approximates the threshold one for rats. The established markers of health impairments may serve as a starting point in the development of techniques of early diagnosis of copper poisoning.

Elastography of the Liver in Wilson's Disease

Staging of liver fibrosis is of special significance in Wilson's disease as it determines the patient's prognosis and treatment. Histopathological examination is a standard method for fibrosis assessment; however, non-invasive methods like transient elastography and share wave elastography are believed to be reliable and repetitive and are expected to replace liver biopsy in Wilson's disease. This article presents a short description of available elastography techniques and the results of the most recent studies on elastography of the liver in patients with Wilson's disease.

Four-dimensional trapped ion mobility spectrometry lipidomics for high throughput clinical profiling of human blood samples

Lipidomics encompassing automated lipid extraction, a four-dimensional (4D) feature selection strategy for confident lipid annotation as well as reproducible and cross-validated quantification can expedite clinical profiling. Here, we determine 4D descriptors (mass to charge, retention time, collision cross section, and fragmentation spectra) of 200 lipid standards and 493 lipids from reference plasma via trapped ion mobility mass spectrometry to enable the implementation of stringent criteria for lipid annotation. We use 4D lipidomics to confidently annotate 370 lipids in reference plasma samples and 364 lipids in serum samples, and reproducibly quantify 359 lipids using level-3 internal standards. We show the utility of our 4D lipidomics workflow for high-throughput applications by reliable profiling of intra-individual lipidome phenotypes in plasma, serum, whole blood, venous and finger-prick dried blood spots.

The role of intestine in metabolic dysregulation in murine Wilson disease

Background and aims

Major clinical manifestations of Wilson disease (WD) are related to copper accumulation in the liver and the brain, and little is known about other tissues involvement in metabolic changes in WD. In vitro studies suggested that the loss of intestinal ATP7B could contribute to metabolic dysregulation in WD. We tested this hypothesis by evaluating gut microbiota and lipidome in two mouse models of WD and by characterizing a new mouse model with a targeted deletion of Atp7b in intestine.

Methods

Cecal content 16S sequencing and untargeted hepatic and plasma lipidome analyses in the Jackson Laboratory toxic-milk and the Atp7b null global knockout mouse models of WD were profiled and integrated. Intestine-specific Atp7b knockout mice ( Atp7b ΔIEC ) was generated using B6.Cg-Tg(Vil1-cre)997Gum/J mice and Atp7b Lox/Lox mice, and characterized using targeted lipidome analysis following a high-fat diet challenge.

Results

Gut microbiota diversity was reduced in animal models of WD. Comparative prediction analysis revealed amino acid, carbohydrate, and lipid metabolism functions to be dysregulated in the WD gut microbial metagenome. Liver and plasma lipidomic profiles showed dysregulated tri- and diglyceride, phospholipid, and sphingolipid metabolism in WD models. When challenged with a high-fat diet, Atp7b ΔIEC mice exhibited profound alterations to fatty acid desaturation and sphingolipid metabolism pathways as well as altered APOB48 distribution in intestinal epithelial cells.

Conclusion

Coordinated changes of gut microbiome and lipidome analyses underlie systemic metabolic manifestations in murine WD. Intestine-specific ATP7B deficiency affected both intestinal and systemic response to a high-fat challenge. WD is a systemic disease in which intestinal-specific ATP7B loss and diet influence phenotypic presentations.