Association between genetically predicted leukocyte telomere length and non-scarring alopecia: A two-sample Mendelian randomization study

Exploring the causal relationship between iron status and subarachnoid hemorrhage based on two sample mendelian randomization

This study investigates the causal association between genetic prediction of iron status and subarachnoid hemorrhage (SAH). A two-sample MR analysis was conducted using genome-wide association study (GWAS) summary data for four iron biomarkers: serum iron, serum ferritin, total iron-binding capacity (TIBC), and transferrin saturation (TSAT). Genetic variants were selected as instrumental variables (IVs) to minimize confounding. Causal estimates were obtained using inverse variance weighting (IVW), MR-Egger, weighted median, and weighted mode methods. Sensitivity analyses, including Cochran's Q-test, MR-Egger regression, MR-PRESSO, and leave-one-out analysis, were performed to assess heterogeneity and pleiotropy. IVW analysis revealed a significant association between increased genetically predicted TIBC and higher SAH risk (OR = 1.71, 95% CI: 1.21-2.41, P = 0.002), while higher TSAT was associated with lower SAH risk (OR = 0.76, 95% CI: 0.62-0.93, P = 0.01). No causal association was found between serum iron, serum ferritin, and SAH. Sensitivity analyses confirmed the robustness of the results, with no evidence of horizontal pleiotropy. However, heterogeneity was detected in serum ferritin, suggesting potential variability in its effect. This MR study provides genetic evidence for the causal relationship between TIBC, TSAT, and SAH risk. These findings highlight the potential role of iron metabolism in SAH pathophysiology, warranting further investigation.

Loss of Ten1 in mice induces telomere shortening and models human dyskeratosis congenita

Telomere length regulation is essential for genome stability as short telomeres can trigger cellular senescence and apoptosis constituting an integral aspect of biological aging. Telomere biology disorders (TBDs) such as dyskeratosis congenita (DC) are rare, inherited diseases with known mutations in at least 16 different genes encoding components of the telomere maintenance complexes. The precise role of TEN1, part of the CST complex (CTC1, STN1, and TEN1), and the consequences of its loss of function in vivo are not yet known. We investigated the first viable murine model of Ten1 deficiency created by CRISPR-Cas9-mediated exon 3 deletion. Ten1 homozygous knockout mice present with telomere attrition, short life span, skin hyperpigmentation, aplastic anemia, and cerebellar hypoplasia. Molecular analyses revealed a reduction of proliferating cells, increased apoptosis, and stem cell depletion with activation of the p53/p21 signaling pathway. Our data demonstrate that Ten1 deficiency causes telomere shortening and associates with accelerated aging.

Telomere Length as Both Cause and Consequence in Type 1 Diabetes: Evidence from Bidirectional Mendelian Randomization

Background/Objectives: Diabetes is the most prevalent metabolic disease globally, characterized by dysregulated glucose control and accompanied by multiple refractory complications. As a critical marker of cellular homeostasis, telomere length (TL) may be associated with the progression of diabetes. However, the causal relationship between diabetes and TL remains unclear, particularly whether cellular homeostasis imbalance acts as a consequence of diabetic complications or a precipitating factor in disease development. Methods: We performed a bidirectional Mendelian randomization (MR) analysis using genome-wide association study (GWAS) data. Following the three core assumptions of MR analysis, we conducted quality control on all instrumental variables to ensure methodological rigor. The inverse variance weighted (IVW) method served as the primary analytical method, supplemented by additional MR methods to evaluate the significance of the results. Furthermore, we performed sensitivity analyses to ensure the reliability and robustness of the findings. Results: Forward analysis revealed that shortened TL significantly increases the risk of broadly defined Type 1 diabetes (T1D) and unspecified types of diabetes (p < 0.05). Additionally, we identified a positive causal relationship between TL and several diabetes-related complications, including co-morbidities, diabetic nephropathy, and diabetic ketoacidosis (p < 0.05). Interestingly, the reverse analysis demonstrated a positive causal effect of T1D and its complications on TL (p < 0.05); however, this effect disappeared after adjusting for insulin use (p > 0.05). Conclusions: Bidirectional MR analyses revealed a complex relationship between TL and T1D, where shortened telomeres increase T1D risk while T1D itself may trigger compensatory mechanisms affecting telomere maintenance, with insulin playing a crucial regulatory role in this relationship. These findings suggest telomere biology may be fundamentally involved in T1D pathogenesis and could inform future therapeutic approaches.

Cardamonin-loaded liposomal formulation for improving percutaneous penetration and follicular delivery for androgenetic alopecia

Androgenic alopecia (AGA) has a considerable impact on the physical and mental health of patients. Nano preparations have apparent advantages and high feasibility in the treatment of AGA. Cardamonin (CAR) has a wide range of pharmacological activities, but it has the problems of poor solubility in water and low bioavailability. There are few, if any, researches on the use of nano-loaded CAR to improve topical skin delivery of AGA. In this study, a CAR-loaded liposomal formulation (CAR@Lip and CAR@Lip Gel) was developed and characterized. The prepared CAR@Lip exhibited a uniform and rounded vesicle in size. CAR@Lip and CAR@Lip Gel can significantly improve the cumulative release of CAR. Additionally, CAR@Lip can obviously promote the proliferation and migration of human dermal papilla cells (hDPCs). Cell uptake revealed that the uptake of CAR@Lip significantly increased compared with the free drug. Furthermore, both CAR@Lip and CAR@Lip Gel groups could markedly improve the transdermal performance of CAR, and increase the topical content of the drug in the hair follicle compared with CAR. The ratchet effect of hair follicles could improve the skin penetration depth of nanoformulations. Notably, Anti-AGA tests in the mice showed that CAR@Lip and CAR@Lip Gel groups could promote hair growth, and accelerate the transition of hair follicles to the growth stage. The anti-androgen effect was revealed by regulating the expression of IGF-1, VEGF, KGF, and TGF-β, participating in SHH/Gli and Wnt/β-catenin pathways. Importantly, the nanoformulations had no obvious skin irritation. Thus, our study showed that CAR-loaded liposomal formulation has potential application in the treatment of AGA.

Impact of epicardial adipose tissue on cardiac function and morphology in patients with diastolic dysfunction

AIMS

This study aimed to identify the impact of increased epicardial adipose tissue (EAT) and its regional distribution on cardiac function in patients with diastolic dysfunction.

METHODS AND RESULTS

Sixty-eight patients with exertional dyspnoea (New York Heart Association ≥II), preserved ejection fraction (≥50%), and diastolic dysfunction (E/e' ≥ 8) underwent rest and stress right heart catheterization, transthoracic echocardiography, and cardiovascular magnetic resonance (CMR). EAT volumes were depicted from CMR short-axis stacks. First, the impact of increased EAT above the median was investigated. Second, the association of ventricular and atrial EAT with myocardial deformation at rest and during exercise stress was analysed in a multivariable regression analysis. Patients with high EAT had higher HFA-PEFF and H2FPEFF scores as well as N-terminal prohormone of brain natriuretic peptide levels (all P < 0.048). They were diagnosed with manifest heart failure with preserved ejection fraction (HFpEF) more frequently (low EAT: 37% vs. high EAT: 64%; P = 0.029) and had signs of adverse remodelling indicated by higher T1 times (P < 0.001). No differences in biventricular volumetry and left ventricular mass (all P > 0.074) were observed. Patients with high EAT had impaired atrial strain at rest and during exercise stress, and impaired ventricular strain during exercise stress. Regionally increased EAT was independently associated with functional impairment of the adjacent chambers.

CONCLUSIONS

Patients with diastolic dysfunction and increased EAT show more pronounced signs of diastolic functional failure and adverse structural remodelling. Despite similar morphological characteristics, patients with high EAT show significant cardiac functional impairment, in particular in the atria. Our results indicate that regionally increased EAT directly induces atrial functional failure, which represents a distinct pathophysiological feature in HFpEF.

Elucidating causal relationships of diet-derived circulating antioxidants and the risk of non-scarring alopecia: A Mendelian randomization study

Previous observational studies revealed controversy about the effect of circulating antioxidants on risk of alopecia. In the present study, we investigated the causal relationships between diet-derived circulating antioxidants and 2 non-scarring alopecia using Mendelian randomization (MR). Instrumental variables for antioxidants (lycopene, retinol, ascorbate, β-carotene, α-tocopherol, and γ-tocopherol) were selected from published studies. Data for alopecia areata (AA) and androgenetic alopecia (AGA) was obtained from the FinnGen study project (R9 released in 2023), including 195 cases and 201,019 controls for AGA and 682 cases and 361,140 controls for AA. We used the inverse variance weighted method as the primary MR method. Three additional methods were used as sensitivity analysis to validate the robustness of the results. We found a causal relationship between absolute β-carotene levels and AGA risk (P = .039), but not with AA (P = .283). The results of Wald ratio showed a protective effect of absolute β-carotene levels against AGA, with per 0.1 ln-transformed β-carotene being associated with a 76% lower risk of AGA (OR: 0.24, 95% CI: 0.06-0.93). Based on the fixed effects inverse variance weighting results, we found that α-tocopherol was protective against both AGA (P = .026) and AA (P = .018). For each unit increase in α-tocopherol, the effects of change in AGA and AA were 0.02 (95% CI: 0.00-0.61) and 0.10 (95% CI: 0.01-0.67), respectively. The results did not reveal any other causal relationships. Our study identified 3 causal associations of antioxidants with the risk of non-scarring alopecia. These results provide new insights into the prevention of non-scarring alopecia through diet.

Actinobacillus pleuropneumoniae, surface proteins and virulence: a review

Actinobacillus pleuropneumoniae (App) is a globally distributed Gram-negative bacterium that produces porcine pleuropneumonia. This highly contagious disease produces high morbidity and mortality in the swine industry. However, no effective vaccine exists to prevent it. The infection caused by App provokes characteristic lesions, such as edema, inflammation, hemorrhage, and necrosis, that involve different virulence factors. The colonization and invasion of host surfaces involved structures and proteins such as outer membrane vesicles (OMVs), pili, flagella, adhesins, outer membrane proteins (OMPs), also participates proteases, autotransporters, and lipoproteins. The recent findings on surface structures and proteins described in this review highlight them as potential immunogens for vaccine development.

Advanced methods and novel biomarkers in autoimmune diseases ‑ a review of the recent years progress in systemic lupus erythematosus

There are several autoimmune and rheumatic diseases affecting different organs of the human body. Multiple sclerosis (MS) mainly affects brain, rheumatoid arthritis (RA) mainly affects joints, Type 1 diabetes (T1D) mainly affects pancreas, Sjogren's syndrome (SS) mainly affects salivary glands, while systemic lupus erythematosus (SLE) affects almost every organ of the body. Autoimmune diseases are characterized by production of autoantibodies, activation of immune cells, increased expression of pro-inflammatory cytokines, and activation of type I interferons. Despite improvements in treatments and diagnostic tools, the time it takes for the patients to be diagnosed is too long, and the main treatment for these diseases is still non-specific anti-inflammatory drugs. Thus, there is an urgent need for better biomarkers, as well as tailored, personalized treatment. This review focus on SLE and the organs affected in this disease. We have used the results from various rheumatic and autoimmune diseases and the organs involved with an aim to identify advanced methods and possible biomarkers to be utilized in the diagnosis of SLE, disease monitoring, and response to treatment.

Modulation of immunity by tryptophan microbial metabolites

Tryptophan (Trp) is an essential amino acid that can be metabolized via endogenous and exogenous pathways, including the Kynurenine Pathway, the 5-Hydroxyindole Pathway (also the Serotonin pathway), and the Microbial pathway. Of these, the Microbial Trp metabolic pathways in the gut have recently been extensively studied for their production of bioactive molecules. The gut microbiota plays an important role in host metabolism and immunity, and microbial Trp metabolites can influence the development and progression of various diseases, including inflammatory, cardiovascular diseases, neurological diseases, metabolic diseases, and cancer, by mediating the body's immunity. This review briefly outlines the crosstalk between gut microorganisms and Trp metabolism in the body, starting from the three metabolic pathways of Trp. The mechanisms by which microbial Trp metabolites act on organism immunity are summarized, and the potential implications for disease prevention and treatment are highlighted.