Association of ACE2 variant rs4646188 with the risks of atrial fibrillation and cardioembolic stroke in Uygur patients with type 2 diabetes

Untargeted metabolomics uncovers metabolic dysregulation and tissue sensitivity in ACE2 knockout mice

Angiotensin-converting enzyme 2 (ACE2) polymorphisms are associated with increased risk of type 2 diabetes mellitus (T2DM), obesity and dyslipidemia, which have been determined in various populations. Consistently, ACE2 knockout (ACE2 KO) mice display damaged energy metabolism in multiple tissues, especially the key metabolic tissues such as liver, skeletal muscle and epididymal white adipose tissue (eWAT) and show even more severe phenotype under high-fat diet (HFD) induced metabolic stress. However, the effects of ACE2 on global metabolomics profiling and the tissue sensitivity remain unclear. To understand how tissues independently and collectively respond to ACE2, we performed untargeted metabolomics in serum in ACE2 KO and control wild type (WT) mice both on normal diet (ND) and HFD, and in three key metabolic tissues (liver, skeletal muscle and eWAT) after HFD treatment. The results showed significant alterations in metabolic profiling in ACE2 KO mice. We identified 275 and 168 serum metabolites differing significantly between WT and ACE2 KO mice fed on ND and HFD, respectively. And the altered metabolites in the ACE2 KO group varied from 90 to 196 in liver, muscle and eWAT. The alterations in ND and HFD serum were most similar. Compared with WT mice, ACE2 KO mice showed an increase in N-phenylacetylglutamine (PAGln), methyl indole-3-acetate, 5-hydroxytryptophol, cholic acid, deoxycholic acid and 12(S)-HETE, while LPC (19:0) and LPE (16:1) decreased. Moreover, LPC (20:0), LPC (20:1) and PC (14:0e/6:0) were reduced in both ND and HFD serum, paralleling the decreases identified in HFD skeletal muscle. Interestingly, DL-tryptophan, indole and Gly-Phe decreased in both ND and HFD serum but were elevated in HFD liver of ACE2 KO mice. A low level of l-ergothioneine was observed among liver, muscle, and epididymal fat tissue of ACE2 KO mice. Pathway analysis demonstrated that different tissues exhibited different dysregulated metabolic pathways. In conclusion, these results revealed that ACE2 deficiency leads to an overall state of metabolic distress, which may provide a new insight into the underlying pathogenesis in metabolic disorders in both ACE2 KO mice and in patients with certain genetic variant of ACE2 gene.

The Impact of ACE2 Polymorphisms on COVID-19 Disease: Susceptibility, Severity, and Therapy

The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has currently spread worldwide, leading to high morbidity and mortality. As the putative receptor of SARS-CoV-2, angiotensin-converting enzyme 2 (ACE2) is widely distributed in various tissues and organs of the human body. Simultaneously, ACE2 acts as the physiological counterbalance of ACE providing homeostatic regulation of circulating angiotensin II levels. Given that some ACE2 variants are known to cause an increase in the ligand-receptor affinity, their roles in acquisition, progression and severity of COVID-19 disease have aroused widespread concerns. Therefore, we summarized the latest literature and explored how ACE2 variants and epigenetic factors influence an individual’s susceptibility to SARS-CoV-2 infection and disease outcome in aspects of ethnicity, gender and age. Meanwhile, the possible mechanisms for these phenomena were discussed. Notably, recombinant human ACE2 and ACE2-derived peptides may have special benefits for combating SARS-CoV-2 variants and further studies are warranted to confirm their effects in later stages of the disease process. As the uncertainty regarding the severity and transmissibility of disease rises, a more in-depth understanding of the host genetics and functional characteristics of ACE2 variants will not only help explain individual clinical differences of the disease, but also contribute to providing effective measures to develop solutions and manage future outbreaks of SARS-CoV-2.

Association between the APOE gene polymorphism and lipid profile and the risk of atrial fibrillation

Background

The relationship between the APOE gene polymorphism and lipid profiles and atrial fibrillation (AF) remains controversial. The current study purposed to investigate how the APOE gene SNPs (rs429358 and rs7412) and lipid profile are associated with the risk for AF among the Hakka population in southern China.

Methods

Finally, 1367 patients were enrolled in this study, including 706 participants with AF (41 ~ 98 years old, 58.64 % male) and 661 non-AF subjects (28 ~ 95 years old, 59.46 % male). The collected data included baseline characteristics, medical history, laboratory tests and echocardiography parameters. A general linear model (two-way analysis of variance (ANOVA)) and Tukey post-hoc tests were applied to identify an APOE allele, AF group, and interaction effect on lipid profiles. Logistic regression analysis was performed to identify risk factors for AF.

Results

For AF group, the most common genotype was E3/E3 (53.82 %), followed by E3/E4 (28.19 %), E2/E3 (13.60 %), E4/E4 (1.98 %), E2/E4 (1.84 %) and E2/E2 (0.57 %). The two-way ANOVA followed by the Tukey procedure showed the following: the lipid levels depended significantly on AF and APOE allele groups for TG, TC, LDL-C and Apo-B (all P < 0.001), and statistically significant interactions between AF and APOE allele were observed in the above 4 variables (all P < 0.05). Multivariate regression analysis indicated that age ≥ 65years (P < 0.001), high diastolic blood pressure (DBP ≥ 90mm Hg, P = 0.018), a high levels of total cholesterol (TC ≥ 5.2mmol/L, P < 0.001) and triglyceride (TG ≥ 1.7mmol/L, P = 0.028), but not the two SNPs of the APOE gene (rs7412 and rs429358) (OR 1.079, P = 0.683), were significant independent risk factors for AF in the study population.

Conclusions

The principal findings of this study showed that individuals at high risk for AF were those over 65 years of age, higher DBP as well as high levels of TC and TG among the southern China Hakka population. The levels of TG, TC, LDL-C and Apo-B depended significantly on AF and APOE allele groups, and statistically significant interactions between AF and APOE allele were observed in the above 4 variables, although the APOE gene SNPs (rs429358 and rs7412) were no significant risk for AF incidence. Further investigation is needed to elucidate whether other SNPs of the APOE gene have a bearing on AF incidents.

Impact of renin-angiotensin system inhibitors on long-term clinical outcomes of patients with rheumatic heart disease

AIMS

Rheumatic heart disease (RHD) remains a major global health problem. Renin-angiotensin-aldosterone system inhibitors (RAASi) are commonly administered in the treatment of cardiovascular disease, but its role in RHD patients is still limited. We performed a retrospective study to determine the effect of RAASi on long-term outcomes for RHD patients.

METHODS AND RESULTS

A 1:1 propensity score matching was implemented to balance baseline characteristics between groups RAASi and non-RAASi. Cox proportional hazards regression model was used to investigate the associations of RAASi with the risks of all-cause mortality, cardiovascular death (CVD), and cerebrovascular death. Binary logistic regression analysis was used to evaluate the associations of RAASi with the risks of 1, 3, and 5 year heart failure (HF) rehospitalization, new-onset atrial fibrillation (AF), and new-onset stroke. A total of 734 RHD patients were enrolled as study participants; nearly half of these participants had combined valve damage (54.4%), worse New York Heart Association functional class status (III and IV, 55.2%), surgical treatment (54.2%), and AF (65.0%). After propensity score matching, 514 RHD patients were finally analysed. RAASi treatment was associated with decreased risks of all-cause mortality [adjusted hazard ratio (HR) = 0.52, 95% confidence interval (CI): 0.37-0.73, P < 0.001], CVD (adjusted HR = 0.48, 95% CI: 0.30-0.76, P = 0.002), and cerebrovascular death (adjusted HR = 0.22, 95% CI: 0.08-0.60, P = 0.003). Further subgroup analysis showed that RAASi treatment was associated with decreased risks of all-cause mortality (adjusted HR = 0.50, 95% CI: 0.31-0.79, P = 0.004), CVD (adjusted HR = 0.48, 95% CI: 0.25-0.91, P = 0.025), and cerebrovascular death (adjusted HR = 0.19, 95% CI: 0.05-0.65, P = 0.008) in RHD patients without surgical treatment, and better effect was observed in RHD patients with surgical treatment on the risks of all-cause mortality (adjusted HR = 0.47, 95% CI: 0.26-0.85, P = 0.012) and CVD (adjusted HR = 0.43, 95% CI: 0.21-0.90, P = 0.024) except cerebrovascular death (adjusted HR = 0.52, 95% CI: 0.08-3.36, P = 0.491). RAASi treatment was associated with decreased HF rehospitalization risk of 1 year [adjusted odds ratio (OR) = 0.38, 95% CI: 0.23-0.61, P < 0.001], 3 year (adjusted OR = 0.43, 95% CI: 0.28-0.68, P < 0.001), and 5 year (adjusted OR = 0.48, 95% CI: 0.30-0.77, P = 0.002) as well as new-onset AF risk (adjusted OR = 0.38, 95% CI: 0.21-0.68, P = 0.001). RAASi treatment had nothing to do with new-onset stroke risk (adjusted OR = 0.80, 95% CI: 0.47-1.38, P = 0.428).

CONCLUSION

Renin-angiotensin-aldosterone system inhibitor treatment was significantly associated with decreased risks of mortality, HF rehospitalization, and new-onset AF in RHD patients in median 5.9 year follow-up.