Patterns and associated factors of electrocardiographic abnormality among type 2 diabetic patients in Amhara National Regional State Referral Hospitals, Ethiopia: a multicenter institution-based cross-sectional study

BACKGROUND

Cardiovascular diseases are the most causes of mortality and morbidity among diabetes mellitus (DM) patients. Electrocardiographic (ECG) changes are common in the early course of the disease. Little is known about the electrocardiographic abnormalities among type 2 DM patients in Ethiopia. This study determined the overall prevalence, its patterns, and the associated factors of ECG abnormalities among people living with T2DM in Amhara National Regional State referral hospitals, Ethiopia.

METHODS

A multicenter institution-based cross-sectional study was conducted from 01 April to 30 May 2021. A simple random sampling and systematic sampling techniques were employed to select the referral hospitals and study participants, respectively. A digital electrocardiograph was used to measure the ECG parameters and the other data were collected using an interviewer-administered questionnaire. Epi-data version-4.6 and Stata-14 were used for data entry and statistical analysis, respectively. The descriptive statistics were presented with tables and graphs. A binary logistic regression model was fitted to identify associated factors of ECG abnormality. In the final model, statistical significance was decided at p≤0.05, and the strength of association was indicated using an adjusted odds ratio with 95% CI.

RESULTS

Two-hundred and fifty-eight participants (response rate = 99.6%) were included for the analysis. The prevalence of overall ECG abnormality was 45% (95% CI: 39, 51%). On the basis of the electrocardiographic patterns, 57 (21.1%; 95% CI: 14.6, 32.6%) were presented with T-wave abnormality, 36 (14%; 95% CI: 10.1, 18.8%) left axis deviation, and 24 (9.3% [6.3, 13.5%]) sinus tachycardia. Higher monthly income (> 90$) (AOR = 0.51 [0.31, 0.83]), over 10 years duration of DM (AOR = 4.5[1.05, 18.94]), hypertension (AOR = 3.9 [1.6, 9.40]), fasting blood sugar of ≥ 130 mg/dl (AOR = 5.01[2.13, 12.20]), and overweight (AOR = 2.65[1.17, 5.98]) were statistically significant factors of overall ECG abnormality.

CONCLUSIONS

Nearly, half of the participants had at least one ECG abnormality. Higher-income, prolonged disease duration, hypertension, higher fasting blood sugar, and overweight were significantly associated with ECG abnormality. The findings of this study suggest the need to institute routine ECG screening for all T2DM patients to reduce ECG abnormalities and further complications.

Estrogen receptor beta maintains expression of KLF15 to prevent cardiac myocyte hypertrophy in female rodents

Maintaining a healthy, anti-hypertrophic state in the heart prevents progression to cardiac failure. In humans, angiotensin II (AngII) indirectly and directly stimulates hypertrophy and progression, while estrogens acting through estrogen receptor beta (ERβ) inhibit these AngII actions. The KLF15 transcription factor has been purported to provide anti-hypertrophic action. In cultured neonatal rat cardiomyocytes, we found AngII inhibited KLF1 expression and nuclear localization, substantially prevented by estradiol (E2) or β-LGND2 (β-LGND2), an ERβ agonist. AngII stimulation of transforming growth factor beta expression in the myocytes activated p38α kinase via TAK1 kinase, inhibiting KLF15 expression. All was comparably reduced by E2 or β-LGND2. Knockdown of KLF15 in the myocytes induced myocyte hypertrophy and limited the anti-hypertrophic actions of E2 and β-LGND2. Key aspects were confirmed in an in-vivo model of cardiac hypertrophy. Our findings define additional anti-hypertrophic effects of ERβ supporting testing specific receptor agonists in humans to prevent progression of cardiac disease.

Estrogen receptor beta signals to inhibition of cardiac fibrosis

Cardiac fibrosis evolves from the cardiac hypertrophic state. In this respect, estrogen and estrogen receptor beta (ERβ) inhibit the effects of cardiac hypertrophic peptides that also stimulate fibrosis. Here we determine details of the anti-fibrotic functions of ERβ. In acutely isolated rat cardiac fibroblasts. E2 or a specific ERβ agonist (βLGND2) blocked angiotensin II (AngII) signaling to fibrosis. This resulted from ERβ activating protein kinase A and AMP kinase, inhibiting both AngII de-phosphorylation of RhoA and the resulting stimulation of Rho kinase. Inhibition of Rho kinase from ERβ signaling resulted in marked decrease of TGFβ expression, connective tissue growth factor production and function, matrix metalloproteinases 2 and 9 expression and activity, and the conversion of fibroblasts to myofibroblasts. Production of collagens I and III were also significantly decreased. Several important aspects were corroborated in-vivo from βLGND2-treated mice that underwent AngII-induced cardiac hypertrophy. Thus, ERβ in cardiac fibroblasts prevents key aspects of cardiac fibrosis development.

Targeting histone deacetylases: A novel therapeutic strategy for atrial fibrillation

Atrial fibrillation (AF) is a common cardiac arrhythmia associated with high mortality and morbidity. Current treatments of AF have limited efficacy and considerable side effects. Histone deacetylases (HDACs) play critical roles in the pathophysiology of cardiovascular diseases and contribute to the genesis of AF. Therefore, HDAC inhibition may prove a novel therapeutic strategy for AF through upstream therapy and modifications of AF electrical and structural remodeling. In this review, we provide an update of the knowledge of the effects of HDACs and HDAC inhibitors on AF, and dissect potential underlying mechanisms.

Different distribution of Helicobacter pylori EPIYA- cagA motifs and dupA genes in the upper gastrointestinal diseases and correlation with clinical outcomes in iranian patients

AIM

Our aim was to determine the EPIYA-cagA Phosphorylation sites and dupA gene in H. pylori isolates among patients with upper gastrointestinal diseases.

BACKGROUND

Pathogenicity of the cagA-positive Helicobacter pylori is associated with EPIYA motifs and higher number of EPIYA-C segments is a risk factor of gastric cancer, while duodenal ulcer-promoting gene (dupA) is determined as a protective factor against gastric cancer.

PATIENTS AND METHODS

A total of 280 non-repeated gastric biopsies obtained from patients undergoing endoscopy from January 2013 till July 2013. Samples were cultured on selective horse blood agar and incubated in microaerophilic atmosphere. The isolated organisms were identified as H. pylori by Gram staining and positive oxidase, catalase, and urease tests. Various motif types of cagA and the prevalence of dupA were determined by PCR method.

RESULTS

Out of 280 specimens, 128 (54.7%) isolated organisms were identified as H. pylori. Of 120 H. pylori isolates, 35.9% were dupA positive and 56.26% were cagA positive, while cagA with ABC and ABCC motifs were 55.5% and 44.5%, respectively. Fifty six percent of the isolates with the ABCC motif have had dupA genes. We also found a significant association between strains with genotypes of dupA-ABC and duodenal ulcer disease (p = 0.007).

CONCLUSION

The results of this study showed that the prevalence of cagA-positive H. pylori in Shiraz was as high as in western countries and higher numbers of EPIYA-C segments were seen in gastric cancer patients. We may also use dupA as a prognostic and pathogenic marker for duodenal ulcer disease and cagA with the segment C for gastric cancer and gastric ulcer disease in this region.

Mitral deceleration index is associated with aortic root dilatation and not to biventricular structural changes in essential hypertension

BACKGROUND AND AIM. The ratio of deceleration time to early mitral wave velocity (mitral deceleration index, MDI) has been recently shown to predict cardiovascular events more precisely than deceleration time alone in human hypertension. Data, however, about the relationship of this parameter with cardiac structure are scant. In the present study, we investigated such an association in uncomplicated essential hypertensives. METHODS. A total of 329 hypertensive subjects categorized in tertiles of MDI were considered for the analysis. All patients underwent the following procedures: (i) physical examination and clinic blood pressure measurement; (ii) routine laboratory investigations; (iii) M-mode, two-dimensional and Doppler echocardiography aimed at a comprehensive assessment of left- and right-sided chambers. RESULTS. Unadjusted left ventricular (LV) mass, right ventricular (RV) and aortic root diameter were significantly higher in the upper MDI tertile, but only aortic root diameter remained significant after adjustment for covariates. A progressive, non-significant increase in biventricular hypertrophy occurred across the MDI tertiles. In a multivariate analysis, MDI was significantly associated with age (β = 0.229, p = 0.001) and aortic root diameter (β = 0.226, p = 0.001); this was not the case for deceleration time alone. No association between MDI and LV as well as RV structural parameters was found. CONCLUSION. Our findings indicate that MDI is unrelated to LV and RV structural changes. Altered LV diastolic function, as assessed by MDI but not by deceleration time alone, is independently associated with aortic root dilatation, a phenotype predictive of incident cardiovascular morbidity and mortality.

Roles and targets of class I and IIa histone deacetylases in cardiac hypertrophy

Cardiac hypertrophy occurs in association with heart diseases and ultimately results in cardiac dysfunction and heart failure. Histone deacetylases (HDACs) are post-translational modifying enzymes that can deacetylate histones and non-histone proteins. Research with HDAC inhibitors has provided evidence that the class I HDACs are pro-hypertrophic. Among the class I HDACs, HDAC2 is activated by hypertrophic stresses in association with the induction of heat shock protein 70. Activated HDAC2 triggers hypertrophy by inhibiting the signal cascades of either Krüppel like factor 4 (KLF4) or inositol polyphosphate-5-phosphatase f (Inpp5f). Thus, modulators of HDAC2 enzymes, such as selective HDAC inhibitors, are considered to be an important target for heart diseases, especially for preventing cardiac hypertrophy. In contrast, class IIa HDACs have been shown to repress cardiac hypertrophy by inhibiting cardiac-specific transcription factors such as myocyte enhancer factor 2 (MEF2), GATA4, and NFAT in the heart. Studies of class IIa HDACs have shown that the underlying mechanism is regulated by nucleo-cytoplasm shuttling in response to a variety of stress signals. In this review, we focus on the class I and IIa HDACs that play critical roles in mediating cardiac hypertrophy and discuss the non-histone targets of HDACs in heart disease.

Estrogen receptor-beta prevents cardiac fibrosis

Development of cardiac fibrosis portends the transition and deterioration from hypertrophy to dilation and heart failure. Here we examined how estrogen blocks this important development. Angiotensin II (AngII) and endothelin-1 induce cardiac hypertrophy and fibrosis in humans. and we find that these agents directly stimulate the transition of the cardiac fibroblast to a myofibroblast. AngII and endothelin-1 stimulated TGFβ1 synthesis in the fibroblast, an inducer of fibrosis that signaled via c-jun kinase to Sma- and Mad-related protein 3 phosphorylation and nuclear translocation in myofibroblasts. As a result, mesenchymal proteins fibronectin and vimentin were produced, as were collagens I and III, the major forms found in fibrotic hearts. 17β-Estradiol (E2) or dipropylnitrile, an estrogen receptor (ER)β agonist, comparably blocked all these events, reversed by estrogen receptor (ER)β small interfering RNA. E2 and dipropylnitrile signaling through cAMP and protein kinase A prevented myofibroblast formation and blocked activation of c-jun kinase and important events of fibrosis. In the hearts of ovariectomized female mice, cardiac hypertrophy and fibrosis were induced by AngII infusion and prevented by E2 administration to wild type but not ERβ knockout rodents. Our results establish the cardiac fibroblast as an important target for hypertrophic/fibrosis-inducing peptides the actions of which were mitigated by E2/ERβ acting in these stromal cells.

The effects of intra-cage aspen tube on cardiac morphology and gene expression

According to the European recommendations rodents should be provided with a nest box if there is insufficient nesting material to build a complete, covered nest. Rats are generally poor nest builders; hence an additional structure is needed. Optimally, housing refinement may be combined with better science; at least it should not detract from the scientific integrity. In order to evaluate these options, there is a need to assess the items used in individual research projects. Studies investigating molecular mechanisms of cardiac hypertrophy and heart failure are typically long-lasting studies; therefore, refinement of the housing of rats in these studies is important. The aim of this study was to evaluate in rats whether a wooden tube has any impact on cardiac morphology or on basal gene expression of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP); known markers of cardiac overload, hypertrophy and heart failure. The experimental protocol simulated cardiovascular studies, but without any surgical operations. A total of 42 male Hsd:SD rats were used in an eight-week experiment. After weaning, the experimental group was provided with a rectangular aspen tube and nesting material, and the control group with only nesting material. ANP and BNP gene expression were measured from the left ventricles with Northern blot analysis postmortem along with the absolute weights of the whole heart, left and right atria and left and right chambers. The weights of the whole heart and left chamber were also analysed in relation to body weight. No statistically significant differences were observed in any of these variables. The inter-individual variation was also unchanged by the cage item. In conclusion, the aspen tube does not disrupt research results or alter the number of animals needed and can therefore be recommended for enrichment purposes in cardiovascular studies.

Resveratrol prevents the development of pathological cardiac hypertrophy and contractile dysfunction in the SHR without lowering blood pressure

BACKGROUND

Cardiac hypertrophy is a compensatory enlargement of the heart in response to stress such as hypertension. It is beneficial in reducing stress placed on the heart. However, when the stress is of a chronic nature, it becomes pathological and leads to cardiac dysfunction and heart failure. Current treatments for hypertension and heart failure have proven beneficial but are not highly specific and associated with side effects. Accordingly, there is an important need for alternative strategies to provide safe and effective treatment.

METHODS

Ten-week-old male spontaneously hypertensive rats (SHRs) and Wistar-Kyoto (WKY) rats were treated with resveratrol (2.5 mg/kg/day) for a period of 10 weeks. Systolic blood pressure, and cardiac structure and function were measured in all groups at different time points of resveratrol treatment. Oxidative stress was also determined in all groups after 10 weeks of resveratrol treatment.

RESULTS

SHRs were characterized with high blood pressure and concentric hypertrophy from 15 weeks of age. Cardiac functional abnormalities were also evident in SHR from 15 weeks onwards. Resveratrol treatment significantly prevented the development of concentric hypertrophy, and systolic and diastolic dysfunction in SHR without lowering blood pressure. Resveratrol also significantly reduced the oxidative stress levels of cardiac tissue in SHR.

CONCLUSIONS

Resveratrol treatment was beneficial in preventing the development of concentric hypertrophy and cardiac dysfunction in SHR. The cardioprotective effect of resveratrol in SHR may be partially mediated by a reduction in oxidative stress. Thus, resveratrol may have potential in preventing cardiac impairment in patients with essential hypertension.