MicroRNA-181 in cardiovascular disease: Emerging biomarkers and therapeutic targets.

Cardiovascular disease (CVD) is the leading cause of death worldwide. MicroRNAs (MiRNAs) have attracted considerable attention for their roles in several cardiovascular disease states, including both the physiological and pathological processes. In this review, we will briefly describe microRNA-181 (miR-181) transcription and regulation and summarize recent findings on the roles of miR-181 family members as biomarkers or therapeutic targets in different cardiovascular-related conditions, including atherosclerosis, myocardial infarction, hypertension, and heart failure. Lessons learned from these studies may provide new theoretical foundations for CVD.

Increased expression of protein tyrosine phosphatase nonreceptor type 22 alters early T-cell receptor signaling and differentiation of CD4+ T cells in chronic heart failure.

CD4+ T-cell counts are increased and activated in patients with chronic heart failure (CHF), whereas regulatory T-cell (Treg) expansion is inhibited, probably due to aberrant T-cell receptor (TCR) signaling. TCR signaling is affected by protein tyrosine phosphatase nonreceptor type 22 (PTPN22) in autoimmune disorders, but whether PTPN22 influences TCR signaling in CHF remains unclear. This observational case-control study included 45 patients with CHF [18 patients with ischemic heart failure versus 27 patients with nonischemic heart failure (NIHF)] and 16 non-CHF controls. We used flow cytometry to detect PTPN22 expression, tyrosine phosphorylation levels, zeta-chain-associated protein kinase, 70 kDa (ZAP-70) inhibitory residue tyrosine 292 and 319 phosphorylation levels, and CD4+ T cell and Treg proportions. We conducted lentivirus-mediated PTPN22 RNA silencing in isolated CD4+ T cells. PTPN22 expression increased in the CD4+ T cells of patients with CHF compared with that in controls. PTPN22 expression was positively correlated with left ventricular end-diastolic diameter and type B natriuretic peptide but negatively correlated with left ventricular ejection fraction in the NIHF group. ZAP-70 tyrosine 292 phosphorylation was decreased, which correlated positively with PTPN22 overexpression in patients with NIHF and promoted early TCR signaling. PTPN22 silencing induced Treg differentiation in CD4+ T cells from patients with CHF, which might account for the reduced frequency of peripheral Tregs in these patients. PTPN22 is a potent immunomodulator in CHF and might play an essential role in the development of CHF by promoting early TCR signaling and impairing Treg differentiation from CD4+ T cells.

Unravelling CD4+ T cell diversity and tissue adaptation of Tregs in abdominal aortic aneurysms through single-cell sequencing.

Immune cell infiltration is a significant pathological process in abdominal aortic aneurysms (AAA). T cells, particularly CD4+ T cells, are essential immune cells responsible for substantial infiltration of the aorta. Regulatory T cells (Tregs) in AAA have been identified as tissue-specific; however, the time, location, and mechanism of acquiring the tissue-specific phenotype are still unknown. Using single-cell RNA sequencing (scRNA-seq) on CD4+ T cells from the AAA aorta and spleen, we discovered heterogeneity among CD4+ T cells and identified activated, proliferating and developed aorta Tregs. These Tregs originate in the peripheral tissues and acquire the tissue-specific phenotype in the aorta. The identification of precursors for Tregs in AAA provides new insight into the pathogenesis of AAA.

Cholesterol suppresses human iTreg differentiation and nTreg function through mitochondria-related mechanisms.

BACKGROUND: Both the crystalline and soluble forms of cholesterol increase macrophage secretion of interleukin 1ß (IL-1ß), aggravating the inflammatory response in atherosclerosis (AS). However, the link between cholesterol and regulatory T cells (Tregs) remains unclear. This study aimed to investigate the effect of cholesterol treatment on Tregs. METHODS: Differentiation of induced Tregs (iTregs) was analyzed using flow cytometry. The expression of hypoxia-inducible factor-1a (HIF-1a) and its target genes was measured by western blotting and/or RT-qPCR. Two reporter jurkat cell lines were constructed by lentiviral transfection. Mitochondrial function and the structure of natural Tregs (nTregs) were determined by tetramethylrhodamine (TMRM) and mitoSOX staining, Seahorse assay, and electron microscopy. The immunoregulatory function of nTregs was determined by nTreg-macrophage co-culture assay and ELISA. RESULTS: Cholesterol treatment suppressed iTreg differentiation and impaired nTreg function. Mechanistically, cholesterol induced the production of mitochondrial reactive oxygen species (mtROS) in naïve T cells, inhibiting the degradation of HIF-1α and unleashing its inhibitory effects on iTreg differentiation. Furthermore, cholesterol-induced mitochondrial oxidative damage impaired the immunosuppressive function of nTregs. Mixed lymphocyte reaction and nTreg-macrophage co-culture assays revealed that cholesterol treatment compromised the ability of nTregs to inhibit pro-inflammatory conventional T cell proliferation and promote the anti-inflammatory functions of macrophages. Finally, mitoTEMPO (MT), a specific mtROS scavenger, restored iTreg differentiation and protected nTreg from further deterioration. CONCLUSION: Our findings suggest that cholesterol may aggravate inflammation within AS plaques by acting on both iTregs and nTregs, and that MT may be a promising anti-atherogenic drug.

Pathogenic Tconvs promote inflammatory macrophage polarization through GM-CSF and exacerbate abdominal aortic aneurysm formation.

Abdominal aortic aneurysms (AAAs) elicit massive inflammatory leukocyte recruitment to the aorta. CD4+ T cells, which include regulatory T cells (Tregs) and conventional T cells (Tconvs), are involved in the progression of AAA. Tregs have been reported to limit AAA formation. However, the function and phenotype of the Tconvs found in AAAs remain poorly understood. We characterized aortic Tconvs by bulk RNA sequencing and discovered that Tconvs in aortic aneurysm highly expressed Cxcr6 and Csf2. Herein, we determined that the CXCR6/CXCL16 signaling axis controlled the recruitment of Tconvs to aortic aneurysms. Deficiency of granulocyte-macrophage colony-stimulating factor (GM-CSF), encoded by Csf2, markedly inhibited AAA formation and led to a decrease of inflammatory monocytes, due to a reduction of CCL2 expression. Conversely, the exogenous administration of GM-CSF exacerbated inflammatory monocyte infiltration by upregulating CCL2 expression, resulting in worsened AAA formation. Mechanistically, GM-CSF upregulated the expression of interferon regulatory factor 5 to promote M1-like macrophage differentiation in aortic aneurysms. Importantly, we also demonstrated that the GM-CSF produced by Tconvs enhanced the polarization of M1-like macrophages and exacerbated AAA formation. Our findings revealed that GM-CSF, which was predominantly derived from Tconvs in aortic aneurysms, played a pathogenic role in the progression of AAAs and may represent a potential target for AAA treatment.

The Landscape of Circular RNAs in Cardiovascular Diseases.

Cardiovascular disease (CVD) remains the leading cause of mortality globally. Circular RNAs (circRNAs) have attracted extensive attention for their roles in the physiological and pathological processes of various cardiovascular diseases (CVDs). In this review, we briefly describe the current understanding of circRNA biogenesis and functions and summarize recent significant findings regarding the roles of circRNAs in CVDs. These results provide a new theoretical basis for diagnosing and treating CVDs.

A Unique Population of Regulatory T Cells in Heart Potentiates Cardiac Protection From Myocardial Infarction.

BACKGROUND: Regulatory T cells (Tregs), traditionally recognized as potent suppressors of immune response, are increasingly attracting attention because of a second major function: residing in parenchymal tissues and maintaining local homeostasis. However, the existence, unique phenotype, and function of so-called tissue Tregs in the heart remain unclear. METHODS: In mouse models of myocardial infarction (MI), myocardial ischemia/reperfusion injury, or cardiac cryoinjury, the dynamic accumulation of Tregs in the injured myocardium was monitored. The bulk RNA sequencing was performed to analyze the transcriptomic characteristics of Tregs from the injured myocardium after MI or ischemia/reperfusion injury. Photoconversion, parabiosis, single-cell T-cell receptor sequencing, and adoptive transfer were applied to determine the source of heart Tregs. The involvement of the interleukin-33/suppression of tumorigenicity 2 axis and Sparc (secreted acidic cysteine-rich glycoprotein), a molecule upregulated in heart Tregs, was further evaluated in functional assays. RESULTS: We showed that Tregs were highly enriched in the myocardium of MI, ischemia/reperfusion injury, and cryoinjury mice. Transcriptomic data revealed that Tregs isolated from the injured hearts had plenty of differentially expressed transcripts in comparison with their lymphoid counterparts, including heart-draining lymphoid nodes, with a phenotype of promoting infarct repair, indicating a unique characteristic. The heart Tregs were accumulated mainly because of recruitment from the circulating Treg pool, whereas local proliferation also contributed to their expansion. Moreover, a remarkable case of repeatedly detected T-cell receptor of heart Tregs, more than that of spleen Tregs, suggests a model of clonal expansion. Besides, HelioshighNrp-1high phenotype proved the mainly thymic origin of heart Tregs, with a small contribution of phenotypic conversion of conventional CD4+ T cells, proved by the analysis of T-cell receptor repertoires and conventional CD4+ T cells adoptive transfer experiments. The interleukin-33/suppression of tumorigenicity 2 axis was essential for sustaining heart Treg populations. Last, we demonstrated that Sparc, which was highly expressed by heart Tregs, acted as a critical factor to protect the heart against MI by increasing collagen content and boosting maturation in the infarct zone. CONCLUSIONS: We identified and characterized a phenotypically and functionally unique population of heart Tregs that may lay the foundation to harness Tregs for cardioprotection in MI and other cardiac diseases.

Inhibition of fibroblast IL-6 production by ACKR4 deletion alleviates cardiac remodeling after myocardial infarction.

Fibrotic scarring is tightly linked to the development of heart failure in patients with post-myocardial infarction (MI). Atypical chemokine receptor 4 (ACKR4) can eliminate chemokines, such as C-C chemokine ligand 21 (CCL21), which is independently associated with heart failure mortality. However, the role of ACKR4 in the heart during MI is unrevealed. This study aimed to determine whether ACKR4 modulates cardiac remodeling following MI and to illuminate the potential molecular mechanisms. The expression of ACKR4 was upregulated in the border/infarct area, and ACKR4 was predominantly expressed in cardiac fibroblasts (CFs). Knockout of ACKR4 protected against adverse ventricular remodeling in mice post-MI. These protective effects of ACKR4 deficiency were independent of dendritic cell immune response but could be attributed to downregulated CF-derived IL-6, affecting CF proliferation and endothelial cell (EC) functions, which consequently inhibited cardiac fibrosis. ACKR4 promoted IL-6 generation and proliferation of CFs. Besides, ACKR4 induced endothelial-to-mesenchymal transition (EndMT) in ECs through IL-6 paracrine effect. The p38 MAPK/NF-κB signaling pathway was involved in ACKR4 facilitated IL-6 generation. Moreover, ACKR4 overexpression in vivo via AAV9 carrying a periostin promoter aggravated heart functional impairment post-MI, which was abolished by IL-6 neutralizing antibody. Therefore, our study established a novel link between ACKR4 and IL-6 post-MI, indicating that ACKR4 may be a novel therapeutic target to ameliorate cardiac remodeling.

Regulatory B cells improve ventricular remodeling after myocardial infarction by modulating monocyte migration.

Overactivated inflammatory responses contribute to adverse ventricular remodeling after myocardial infarction (MI). Regulatory B cells (Bregs) are a newly discovered subset of B cells with immunomodulatory roles in many immune and inflammation-related diseases. Our study aims to determine whether the expansion of Bregs exerts a beneficial effect on ventricular remodeling and explore the mechanisms involved. Here, we showed that adoptive transfer of Bregs ameliorated ventricular remodeling in a murine MI model, as demonstrated by improved cardiac function, decreased scar size and attenuated interstitial fibrosis without changing the survival rate. Reduced Ly6Chi monocyte infiltration was found in the hearts of the Breg-transferred mice, while the infiltration of Ly6Clo monocytes was not affected. In addition, the replenishment of Bregs had no effect on the myocardial accumulation of T cells or neutrophils. Mechanistically, Bregs reduced the expression of C-C motif chemokine receptor 2 (CCR2) in monocytes, which inhibited proinflammatory monocyte recruitment to the heart from the peripheral blood and mobilization from the bone marrow. Breg-mediated protection against MI was abrogated by treatment with an interleukin 10 (IL-10) antibody. Finally, IL-10 neutralization reversed the effect of Bregs on monocyte migration and CCR2 expression. The present study suggests a therapeutic value of Bregs in limiting ventricular remodeling after MI through decreasing CCR2-mediated monocyte recruitment and mobilization.

Interleukin 35 ameliorates myocardial ischemia-reperfusion injury by activating the gp130-STAT3 axis.

Myocardial ischemia-reperfusion injury (MIRI) is common clinical complication, which represents significant challenge in the treatment of acute myocardial infarction (AMI) diseases. Interleukin 35 (IL-35) exhibits anti-inflammatory properties via the engagement of the gp130, IL-12Rß2 and IL-27Rα receptors. However, whether IL-35 plays a beneficial role in the treatment of MIRI and potential underling mechanism are unclear. We showed that IL-35 conferred protection from MIRI as demonstrated by reduced infarct size and cardiac troponin T, improved cardiac function and decreased cardiomyocyte apoptosis in a mouse model. Despite activation of both STAT3 and STAT5 phosphorylation in the heart by IL-35, signal transducers and activators of transcription 3 (STAT3) was essential for mediating the IL-35-mediated protective effect on MIRI using cardiomyocyte-specific STAT3 deficient mice. Furthermore, gp130 was required for the STAT3 activation and cardio-protection induced by IL-35. Interestingly, IL-35 induced gp130 homodimer and gp130/IL-12Rß2 heterodimers in cardiomyocyte. Our results indicate that IL-35 can execute a protective role against MIRI through a novel signaling pathway, IL-35-gp130-STAT3 pathway, in cardiomyocytes, which may be beneficial for the development of novel and effective therapeutic approaches to treat the MIRI.

IL (Interleukin)-33 Suppresses Abdominal Aortic Aneurysm by Enhancing Regulatory T-Cell Expansion and Activity.

Objective- Inflammation occurs during the progression of abdominal aortic aneurysm (AAA). IL (interleukin)-33 is a pleiotropic cytokine with multiple immunomodulatory effects, yet its role in AAA remains unknown. Approach and Results- Immunoblot, immunohistochemistry, and immunofluorescent staining revealed increased IL-33 expression in adventitia fibroblasts from mouse AAA lesions. Daily intraperitoneal administration of recombinant IL-33 or transgenic IL-33 expression ameliorated periaorta CaPO4 injury- and aortic elastase exposure-induced AAA in mice, as demonstrated by blunted aortic expansion, reduced aortic wall elastica fragmentation, enhanced AAA lesion collagen deposition, attenuated T-cell and macrophage infiltration, reduced inflammatory cytokine production, skewed M2 macrophage polarization, and reduced lesion MMP (matrix metalloproteinase) expression and cell apoptosis. Flow cytometry analysis, immunostaining, and immunoblot analysis showed that exogenous IL-33 increased CD4+Foxp3+ regulatory T cells in spleens, blood, and aortas in periaorta CaPO4-treated mice. Yet, ST2 deficiency muted these IL-33 activities. Regulatory T cells from IL-33-treated mice also showed significantly stronger activities in suppressing smooth muscle cell inflammatory cytokine and chemokine expression, macrophage MMP expression, and in increasing M2 macrophage polarization than those from vehicle-treated mice. In contrast, IL-33 failed to prevent AAA and lost its beneficial activities in CaPO4-treated mice after selective depletion of regulatory T cells. Conclusions- Together, this study established a role of IL-33 in protecting mice from AAA formation by enhancing ST2-dependent aortic and systemic regulatory T-cell expansion and their immunosuppressive activities.

Pathologic T-cell response in ischaemic failing hearts elucidated by T-cell receptor sequencing and phenotypic characterization.

AIMS: A persistent cardiac T-cell response initiated by myocardial infarction is linked to subsequent adverse ventricular remodelling and progression of heart failure. No data exist on T-cell receptor (TCR) repertoire changes in combination with phenotypic characterization of T cells in ischaemic failing human hearts. METHODS AND RESULTS: Analysis of TCR repertoire with high-throughput sequencing revealed that compared with T cells in control hearts, those in ischaemic failing hearts showed a clonally expanded TCR repertoire but similar usage patterns of TRBV-J rearrangements and V gene segments; compared with T cells in peripheral blood, those in ischaemic failing hearts exhibited a restricted and clonally expanded TCR repertoire and different usage patterns of TRBV-J rearrangements and V gene segments, suggesting the occurrence of tissue-specific T-cell expansion in ischaemic failing hearts. Consistently, TCR clonotype sharing was prominent in ischaemic failing hearts, especially in hearts of patients who shared human leucocyte antigen (HLA) alleles. Furthermore, ischaemia heart failure (IHF) heart-associated clonotypes were more frequent in peripheral blood of IHF patients than in that of controls. Heart-infiltrating T cells displayed memory- and effector-like characteristics. Th1 cells were the predominant phenotype among CD4+ T cells; CD8+ T cells were equally as abundant as CD4+ T cells and produced high levels of interferon-γ, granzyme B, and perforin. CONCLUSION: We provide novel evidence for a tissue-specific T-cell response predominated by Th1 cells and cytotoxic CD8+ T cells in ischaemic failing human hearts that may contribute to the progression of heart failure.

Increased SPK1 expression promotes cell growth by activating the ERK1/2 signaling in non-small-cell lung cancer.

Lung cancer remains the leading cause of cancer-associated mortality in China and the world. Increasing numbers of studies have reported that sphingosine kinase 1 (SPK1) is frequently highly expressed in tumors of various origins, including lung cancer, and its high expression contributes toward tumor progression. However, the clinical significance of SPK1 and its role in the growth and metastasis of non-small-cell lung cancer (NSCLC) remain unclear. In the present study, we found that SPK1 expression was expressed highly in NSCLC tissues and cell lines. Knockdown of SPK1 suppressed cell growth, proliferation, migration, and invasion and increased apoptosis. Moreover, knocking down SPK1 expression inhibited the growth of tumors in nude mice. Mechanistically, silencing the expression of SPK1 inhibited the expression of p-extracellular signal-regulated kinase (ERK). Moreover, the ERK-specific inhibitor U0126 suppressed the expression of the epithelial-mesenchymal transition of lung cancer cells. Together, our findings indicated that SPK1 enhanced tumor growth in lung cancer and induced metastasis by activating the ERK1/2 signaling pathway, indicating its potential application in NSCLC diagnosis and therapy.

Down-regulation of microRNA-451a facilitates the activation and proliferation of CD4+ T cells by targeting Myc in patients with dilated cardiomyopathy.

CD4+ T cells are abnormally activated in patients with dilated cardiomyopathy (DCM) and might be associated with the immunopathogenesis of the disease. However, the underlying mechanisms of CD4+ T cell activation remain largely undefined. Our aim was to investigate whether the dysregulation of microRNAs (miRNAs) was associated with CD4+ T cell activation in DCM. CD4+ T cells from DCM patients showed increased expression levels of CD25 and CD69 and enhanced proliferation in response to anti-CD3/28, indicating an activated state. miRNA profiling analysis of magnetically sorted CD4+ T cells revealed a distinct pattern of miRNA expression in CD4+ T cells from DCM patients compared with controls. The level of miRNA-451a (miR-451a) was significantly decreased in the CD4+ T cells of DCM patients compared with that of the controls. The transfection of T cells with an miR-451a mimic inhibited their activation and proliferation, whereas an miR-451a inhibitor produced the opposite effects. Myc was directly inhibited by miR-451a via interaction with its 3'-UTR, thus identifying it as an miR-451a target in T cells. The knockdown of Myc suppressed the activation and proliferation of T cells, and the expression of Myc was significantly up-regulated at the mRNA level in CD4+ T cells from patients with DCM. A strong inverse correlation was observed between the Myc mRNA expression and miR-451a transcription level. Our data suggest that the down-regulation of miR-451a contributes to the activation and proliferation of CD4+ T cells by targeting the transcription factor Myc in DCM patients and may contribute to the immunopathogenesis of DCM.

Defective Circulating Regulatory B Cells in Patients with Dilated Cardiomyopathy.

BACKGROUND/AIMS: Newly identified IL-10-producing regulatory B cells (Bregs) have been shown to play an important role in the suppression of immune responses. Chronic immune activation participates in the pathogenesis of dilated cardiomyopathy (DCM) but whether Bregs are involved in its development remains unclear. We aimed to investigate the circulating frequency and function of Bregs in DCM. METHODS: In total, 35 DCM patients (20 men and 15 women) and 44 healthy controls (23 men and 21 women) were included in the experiment, and the frequency of Bregs was detected using flow cytometry. RESULTS: According to our results, the frequency of circulating IL-10-producing Bregs was significantly lower in DCM patients compared with healthy controls. Furthermore, the CD24hiCD27+ B cell subset in which IL-10-producing Bregs were mainly enriched from DCM patients showed impaired IL-10 expression and a decreased ability to suppress the TNF-α production of CD4+CD25- Tconv cells and to maintain Tregs differentiation. Correlation analysis showed that the frequency of IL-10-producing Bregs and the suppressive function of CD24hiCD27+ B cells were positively correlated with left ventricular ejection fraction and negatively correlated with NT-proBNP in DCM patients. CONCLUSIONS: In conclusion, the reduced frequency and impaired functions suggest a potential role of Bregs in the development of DCM.

Activated regulatory T-cells attenuate myocardial ischaemia/reperfusion injury through a CD39-dependent mechanism.

Regulatory T-cells (Tregs) are generally regarded as key immunomodulators that maintain immune tolerance and counteract tissue damage in a variety of immune-mediated disorders. However, its role in myocardial ischaemia/reperfusion injury (MIRI) remains unknown. The purpose of the present study was to determine whether Tregs exert a beneficial effect on mouse MIRI. We examined the role of Tregs in murine MIRI by depletion using 'depletion of regulatory T-cell' (DEREG) mice and adoptive transfer using Forkhead box P3 (Foxp3)-GFP knockin mice and the mechanisms of cardio protection were further studied in vivo and in vitro. Tregs rapidly accumulated in murine hearts following MIRI. Selective depletion of Tregs in the DEREG mouse model resulted in aggravated MIRI. In contrast, the adoptive transfer of in vitro-activated Tregs suppressed MIRI, whereas freshly isolated Tregs had no effect. Mechanistically, activated Treg-mediated protection against MIRI was not abrogated by interleukin (IL)-10 or transforming growth factor (TGF)-ß1 inhibition but was impaired by the genetic deletion of cluster of differentiation 39 (CD39). Moreover, adoptive transfer of in vitro-activated Tregs attenuated cardiomyocyte apoptosis, activated a pro-survival pathway involving Akt and extracellular-signal-regulated kinase (ERK) and inhibited neutrophil infiltration, which was compromised by CD39 deficiency. Finally, the peripheral blood mononuclear cells of acute myocardial infarction (AMI) patients after primary percutaneous coronary intervention (PCI) revealed a decrease in CD4+CD25+CD127low Tregs and a relative increase in CD39+ cells within the Treg population. In conclusion, our data validated a protective role for Tregs in MIRI. Moreover, in vitro-activated Tregs ameliorated MIRI via a CD39-dependent mechanism, representing a putative therapeutic strategy.

Metal-free methylation of a pyridine N-oxide C-H bond by using peroxides.

Metal-free methylation of a pyridine N-oxide C-H bond was developed using peroxide as a methyl reagent under neat conditions. Pyridine N-oxide derivatives with various groups (e.g., Cl, NO2, and OCH3) were all suitable substrates, and the desired products were obtained in moderate to excellent yields under standard conditions. Moreover, the methylation can be performed with a good yield on the gram-scale experiment. Tentative mechanistic studies show that the methylation is a classical radical process.

Sphingosine kinase-1 protects differentiated N2a cells against beta-amyloid25-35-induced neurotoxicity via the mitochondrial pathway.

Although the etiology of Alzheimer's disease (AD) is not fully understood, multiple lines of evidence suggests the importance of amyloid-ß (Aß) in the initiation/progression of the disease. Aß has been shown to induce neuronal apoptosis via the sphingomyelin/ceramide pathway. This study was designed to elucidate whether the sphingosine kinase-1 (SPK1), a critical regulator of the ceramide/sphingosine 1-phosphate rheostat, plays a pivotal role in the regulation of death and survival of differentiated neuro-2a cells in response to beta-amyloid peptide fragment 25-35 (Aß25-35). These results show that the expression of SPK1 was markedly decreased in Aß25-35-induced neurotoxicity, as evidenced by the decreased cell viability and the increased apoptotic rate. Overexpression of SPK1 significantly attenuated Aß25-35-induced neurotoxicity, whereas silencing the expression of SPK1 exacerbated it. Moreover, overexpression of SPK1 can significantly attenuate Aß25-35-induced upregulation of Bax and rehabilitate the level of Bcl-2; concomitantly, it can ameliorate mitochondrial ultrastructure. These studies demonstrate that overexpression of SPK1 may moderate Aß25-35-induced neurotoxicity by regulating the Bcl-2/Bax ratio and improving mitochondrial ultrastructure. Based on these findings, SPK1 is a potential therapeutic target for AD.

Case Report: A rare transthyretin mutation p.D58Y in a Chinese case of transthyretin amyloid cardiomyopathy.

Hereditary transthyretin amyloid (ATTRv) cardiomyopathy (CM) is caused by mutations in the TTR gene. TTR mutations contribute to TTR tetramer destabilization and dissociation, leading to excessive deposition of insoluble amyloid fibrils in the myocardium and finally resulting in cardiac dysfunction. In this article, we report a case of a Chinese patient with transthyretin mutation p.D58Y and provide detailed information on cardiac amyloidosis, including transthoracic echocardiography, cardiac magnetic resonance, and SPECT imaging for the first time. Our report aims to provide a better understanding of ATTR genotypes and phenotypes.