Herpud1 deficiency could reduce amyloid-β40 expression and thereby suppress homocysteine-induced atherosclerosis by blocking the JNK/AP1 pathway

Atherosclerosis is associated with plasma Aβ levels in non-hypertension patients

BACKGROUND

Growing evidence indicated that to develop of atherosclerosis observed more often by people with Alzheimer's disease (AD), but the underlying mechanism is not fully clarified. Considering that amyloid-β (Aβ) deposition in the brain is the key pathophysiology of AD and plasma Aβ is closely relate to Aβ deposition in the brain, in the present study, we investigated the relationships between atherosclerosis and plasma Aβ levels.

METHODS

This was a population based cross-sectional study. Patients with high risk of atherosclerosis from Qubao Village, Xi'an were underwent carotid ultrasound for assessment of atherosclerosis. Venous blood was collected on empty stomach in the morning and plasma Aβ1-40 and Aβ1-42 levels were measured using ELISA. Multivariate logistic regression analysis was performed to investigate the relationships between carotid atherosclerosis (CAS) and plasma Aβ levels.

RESULTS

Among 344 patients with high risk of atherosclerosis, 251(73.0%) had CAS. In the univariate analysis, the plasma Aβ levels had no significant differences between CAS group and non-CAS group (Aβ1-40: 53.07 ± 9.24 pg/ml vs. 51.67 ± 9.11pg/ml, p = 0.211; Aβ1-42: 40.10 ± 5.57 pg/ml vs. 40.70 pg/ml ± 6.37pg/ml, p = 0.285). Multivariate logistic analysis showed that plasma Aβ levels were not associated with CAS (Aβ1-40: OR = 1.019, 95%CI: 0.985-1.054, p = 0.270;Aβ1-42: OR = 1.028, 95%CI: 0.980-1.079, p = 0.256) in the total study population. After stratified by hypertension, CAS was associated with plasma Aβ1-40 positively (OR = 1.063, 95%CI: 1.007-1.122, p = 0.028) in the non-hypertension group, but not in hypertensive group. When the plasma Aβ concentrations were classified into four groups according to its quartile, the highest level of plasma Aβ1-40 group was associated with CAS significantly (OR = 4.465, 95%CI: 1.024-19.474, p = 0.046).

CONCLUSION

Among patients with high risk of atherosclerosis, CAS was associated with higher plasma Aβ1-40 level in non-hypertension group, but not in hypertension group. These indicated that atherosclerosis is associated with plasma Aβ level, but the relationship may be confounded by hypertension.

HERPUD1 governs tumor cell mitochondrial function via inositol 1,4,5-trisphosphate receptor-mediated calcium signaling

The intricate relationship between calcium (Ca2+) homeostasis and mitochondrial function is crucial for cellular metabolic adaptation in tumor cells. Ca2+-initiated signaling maintains mitochondrial respiratory capacity and ATP synthesis, influencing critical cellular processes in cancer development. Previous studies by our group have shown that the homocysteine-inducible ER Protein with Ubiquitin-Like Domain 1 (HERPUD1) regulates inositol 1,4,5-trisphosphate receptor (ITPR3) levels and intracellular Ca2+ signals in tumor cells. This study explores the role of HERPUD1 in regulating mitochondrial function and tumor cell migration by controlling ITPR3-dependent Ca2+ signals. We found HERPUD1 levels correlated with mitochondrial function in tumor cells, with HERPUD1 deficiency leading to enhanced mitochondrial activity. HERPUD1 knockdown increased intracellular Ca2+ release and mitochondrial Ca2+ influx, which was prevented using the ITPR3 antagonist xestospongin C or the Ca2+ chelator BAPTA-AM. Furthermore, HERPUD1 expression reduced tumor cell migration by controlling ITPR3-mediated Ca2+ signals. HERPUD1-deficient cells exhibited increased migratory capacity, which was attenuated by treatment with xestospongin C or BAPTA-AM. Additionally, HERPUD1 deficiency led to reactive oxygen species-dependent activation of paxillin and FAK proteins, which are associated with enhanced cell migration. Our findings highlight the pivotal role of HERPUD1 in regulating mitochondrial function and cell migration by controlling intracellular Ca2+ signals mediated by ITPR3. Understanding the interplay between HERPUD1 and mitochondrial Ca2+ regulation provides insights into potential therapeutic targets for cancer treatment and other pathologies involving altered energy metabolism.

TGFB3-AS1 promotes Hcy-induced inflammation of macrophages via inhibiting the maturity of miR-144 and upregulating Rap1a

It has been demonstrated that homocysteine (Hcy) can cause inflammatory diseases. Long noncoding RNAs (lncRNA) and microRNAs (miRNAs) are involved in this biological process, but the mechanism underlying Hcy-induced inflammation remains poorly understood. Here, we found that lncRNA TGFB3-AS1 was highly expressed in macrophages treated with Hcy and the peripheral blood monocytes from cystathionine beta-synthase heterozygous knockout (CBS^+/−) mice with a high-methionine diet using lncRNA microarray. In vivo and in vitro experiments further confirmed that TGFB3-AS1 accelerated Hcy-induced inflammation of macrophages through the Rap1a/wnt signaling pathway. Meanwhile, TGFB3-AS1 interacted with Rap1a and reduced degradation of Rap1a through inhibiting its ubiquitination in macrophages treated with Hcy. Rap1a mediated inflammation induced by Hcy and serves as a direct target of miR-144. Moreover, TGFB3-AS1 regulated miR-144 by binding to pri-miR-144 and inhibiting its maturation, which further regulated Rap1a expression. More importantly, we found that high expression of TGFB3-AS1 was positively correlated with the levels of Hcy and proinflammatory cytokines in serum of healthy individuals and patients with HHcy. Our study revealed a novel mechanism by which TGFB3-AS1 promoted inflammation of macrophages through inhibiting miR-144 maturation to stay miR-144 regulated inhibition of functional Rap1a expression.

Dysregulated gene-associated biomarkers for Alzheimer's disease and aging

Alzheimer’s disease (AD), the most common type of dementia, is a neurodegenerative disorder with a hidden onset, including difficult early detection and diagnosis. Nevertheless, the new crucial biomarkers for the diagnosis and pathogenesis of AD need to be explored further. Here, the common differentially expressed genes (DEGs) were identified through a comprehensive analysis of gene expression profiles from the Gene Expression Omnibus (GEO) database. Furthermore, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses revealed that these DEGs were mainly associated with biological processes, cellular components, and molecular functions, which are involved in multiple cellular functions. Next, we found that 9 of the 24 genes showed the same regulatory changes in the blood of patients with AD compared to those in the GEO database, and 2 of the 24 genes showed a significant correlation with Montreal Cognitive Assessment scores. Finally, we determined that mice with AD and elderly mice had the same regulatory changes in the identified DEGs in both the blood and hippocampus. Our study identified several potential core biomarkers of AD and aging, which could contribute to the early detection, differential diagnosis, treatment, and pathological analysis of AD.

M2 macrophage-derived exosomes promote the c-KIT phenotype of vascular smooth muscle cells during vascular tissue repair after intravascular stent implantation

Rationale: For intravascular stent implantation to be successful, the processes of vascular tissue repair and therapy are considered to be critical. However, the mechanisms underlying the eventual fate of vascular smooth muscle cells (VSMCs) during vascular tissue repair remains elusive. In this study, we hypothesized that M2 macrophage-derived exosomes to mediate cell-to-cell crosstalk and induce dedifferentiation phenotypes in VSMCs. Methods: In vivo, 316L bare metal stents (BMS) were implanted from the left iliac artery into the abdominal aorta of 12-week-old male Sprague-Dawley (SD) rats for 7 and 28 days. Hematoxylin and eosin (HE) were used to stain the neointimal lesions. En-face immunofluorescence staining of smooth muscle 22 alpha (SM22α) and CD68 showed the rat aorta smooth muscle cells (RASMCs) and macrophages. Immunohistochemical staining of total galactose-specific lectin 3 (MAC-2) and total chitinase 3-like 3 (YM-1) showed the total macrophages and M2 macrophages. In vitro, exosomes derived from IL-4+IL-13-treated macrophages (M2Es) were isolated by ultracentrifugation and characterized based on their specific morphology. Ki-67 staining was conducted to assess the effects of the M2Es on the proliferation of RASMCs. An atomic force microscope (AFM) was used to detect the stiffness of the VSMCs. GW4869 was used to inhibit exosome release. RNA-seq was performed to determine the mRNA profiles of the RASMCs and M2Es-treated RASMCs. Quantitative real-time PCR (qRT-PCR) analysis was conducted to detect the expression levels of the mRNAs. Western blotting was used to detect the candidate protein expression levels. T-5224 was used to inhibit the DNA binding activity of AP-1 in RASMCs. Results: M2Es promote c-KIT expression and softening of nearby VSMCs, hence accelerating the vascular tissue repair process. VSMCs co-cultured in vitro with M2 macrophages presented an increased capacity for de-differentiation and softening, which was exosome dependent. In addition, the isolated M2Es helped to promote VSMC dedifferentiation and softening. Furthermore, the M2Es enhanced vascular tissue repair potency by upregulation of VSMCs c-KIT expression via activation of the c-Jun/activator protein 1 (AP-1) signaling pathway. Conclusions: The findings of this study emphasize the prominent role of M2Es during VSMC dedifferentiation and vascular tissue repair via activation of the c-Jun/AP-1 signaling pathway, which has a profound impact on the therapeutic strategies of coronary stenting techniques.