Brain Natriuretic Peptide (BNP) as a Biomarker of Myocardial Ischemia-Reperfusion Injury in Cardiac Transplantation

Design and synthesis of matrine derivatives for anti myocardial ischemia-reperfusion injury by promoting angiogenesis

Myocardial ischemia/reperfusion (MI/R) is a common cardiovascular disease that seriously affects the quality of life and prognosis of patients. In recent years, matrine has attracted widespread attention in the treatment of cardiovascular diseases. This study designed, synthesized, and characterized 20 new matrine derivatives and studied their protective effects on ischemia-reperfusion injury through in vivo and in vitro experiments. Based on cellular assays, most newly synthesized derivatives have a certain protective effect on Hypoxia/Reoxygenation (H/R) induced H9C2 cell damage, with compound 22 having the best activity and effectively reducing cell apoptosis and necrosis. In vitro experimental data shows that compound 22 can significantly reduce the infarct size of rat myocardium and improve cardiac function after MI/R injury. In summary, compound 22 is a new potential cardioprotective agent that can promote angiogenesis and enhance antioxidant activity by activating ADCY5, CREB3l4, and VEGFA, thereby protecting myocardial cell apoptosis and necrosis induced by MI/R.

Heart transplantation and biomarkers: a review about their usefulness in clinical practice

Advanced heart failure (AdvHF) can only be treated definitively by heart transplantation (HTx), yet problems such right ventricle dysfunction (RVD), rejection, cardiac allograft vasculopathy (CAV), and primary graft dysfunction (PGD) are linked to a poor prognosis. As a result, numerous biomarkers have been investigated in an effort to identify and prevent certain diseases sooner. We looked at both established biomarkers, such as NT-proBNP, hs-troponins, and pro-inflammatory cytokines, and newer ones, such as extracellular vesicles (EVs), donor specific antibodies (DSA), gene expression profile (GEP), donor-derived cell free DNA (dd-cfDNA), microRNA (miRNA), and soluble suppression of tumorigenicity 2 (sST2). These biomarkers are typically linked to complications from HTX. We also highlight the relationships between each biomarker and one or more problems, as well as their applicability in routine clinical practice.

The correlation of cardiac biomarkers and myocardial iron overload based on T2* MRI in major beta-thalassemia

Cardiac hemosiderosis is the primary factor to derive the pathogenesis of cardiac dysfunction in patients with transfusion dependent thalassemia. Biomarkers assessment along with T2 * MRI study could be employed to evaluate the severity of iron deposition-related damage and determination of the diagnostic and prognostic value of these inflammatory factors. The study was conducted on 62 patients (12-44 years old) with major thalassemia. The patients were under regular blood transfusion and they had no signs of cardiac defects, and chronic diseases. The serum levels of inflammatory factors (NT-proBNP, CRP, Copeptin HS) were determined before routine transfusion. Cardiac iron overload was assessed by T2* MRI (within the last three months), and T2* lower than 20 ms was considered as cardiac siderosis. The obtained results were analyzed using statistical methods. 92% of patients showed an increased level of hs-CRP (> 2 µg/dL). All cases showed increased levels of NT-proBNP (> 150 pg/mL). Only 29% of subjects showed high level of Copeptin, 25.8% of patients demonstrated cardiac siderosis based on the T2* MRI (< 20 ms) results. The serum levels of inflammatory factors were not significantly correlated with cardiac siderosis. Given the obtained results, it could be deduced that the serum levels of inflammatory factors could not be exploited for early detection of cardiac siderosis in major beta-thalassemia patients.

Peptide-Peptide Co-Assembly: A Design Strategy for Functional Detection of C-peptide, A Biomarker of Diabetic Neuropathy

Diabetes-related neuropathy is a debilitating condition that may be averted if it can be detected early. One possible way this can be achieved at low cost is to utilise peptides to detect C-peptide, a biomarker of diabetic neuropathy. This depends on peptide-peptide co-assembly, which is currently in a nascent stage of intense study. Instead, we propose a bead-based triple-overlay combinatorial strategy that can preserve inter-residue information during the screening process for a suitable complementary peptide to co-assemble with C-peptide. The screening process commenced with a pentapeptide general library, which revealed histidine to be an essential residue. Further screening with seven tetrapeptide focused libraries led to a table of self-consistent peptide sequences that included tryptophan and lysine at high frequencies. Three complementary nonapeptides (9mer com-peptides), wpkkhfwgq (Trp-D), kwkkhfwgq (Lys-D), and KWKKHFWGQ (Lys-L) (as a negative control) were picked from this table for co-assembly studies with C-peptide. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) and circular dichroism (CD) spectroscopies were utilized to study inter-peptide interactions and changes in secondary structures respectively. ATR-FTIR studies showed that there is indeed inter-peptide interaction between C-peptide and the tryptophan residues of the 9mer com-peptides. CD studies of unaggregated and colloidal C-peptide with the 9mer com-peptides suggest that the extent of co-assembly of C-peptide with Trp-D is greatest, followed by Lys-D and Lys-L. These results are promising and indicate that the presented strategy is viable for designing and evaluating longer complementary peptides, as well as complementary peptides for co-assembly with other polypeptides of interest and importance. We discuss the possibility of designing complementary peptides to inhibit toxic amyloidosis with this approach.

Perioperative myocardial injury after adult heart transplant: determinants and prognostic value

Background and Aim of the Study

Implications of Cardiac troponin (cTnI) release after cardiac transplantation are still unclear. This study disclosed risk factors and prognostic implication of cTnI early levels in a single centre cohort operated on between January 1999 and December 2010.

Methods

Data on 362 consecutive recipients (mean age: 47.8±13.7, 20.2% female, 18.2% diabetics, 22.1% with previous cardiac operations, 27.6% hospitalized, 84.9±29.4 ml/min preoperative glomerular filtration rate) were analyzed using multivariable logistic regression modeling. Target outcomes were determinants of troponin release, early graft failure (EGF), acute kidney injury (AKI) and operative death.

Results

Mean cTnI release measured 24 hours after transplant was 10.9±11.6 μg/L. Overall hospital mortality was 10.8%, EGF 10.5%, and AKI was 12.2%. cTnI release>10 μg/L proved an independent predictor of EGF (OR 2.2; 95% CI, 1.06–4.6) and AKI (OR 1.031; 95% CI, 1.001-1.064). EGF, in turn, proved a determinant of hospital mortality. Risk factors for cTnI>10 μg/L release were: status 2B (OR 0.35; 95% CI, 0.18-0.69, protective), duration of the ischemic period (OR 1.006; 95% CI, 1.001-1.011), previous cardiac operation (OR 2.9; 95% CI, 1.67-5.0), and left ventricular hypertrophy (OR 3.3; 95% CI, 1.9-5.6).

Conclusions

Myocardial enzyme leakage clearly emerged as an epiphenomenon of more complicated clinical course. The complex interplay between surgical procedure features, graft characteristics and recipient end-organ function highlights cTnI release as a risk marker of graft failure and acute kidney injury. The search for optimal myocardial preservation is still an issue.

B-type natriuretic peptide trends after pediatric heart transplantation

BNP is increasingly utilized in the management of pediatric HT recipients. Performing a retrospective single-center chart review, we sought to describe BNP changes during the first year after HT and identify factors that affect its trend. After exclusion for rejection, 316 BNP levels from 50 patients were evaluated. BNP underwent an exponential decline 120 days after HT followed by a plateau. Log10 BNP decline strongly correlated with time (r = -0.70, p < 0.0001). Initial BNP was less in pretransplant VAD (p = 0.0016) and lower post-HT inotrope use (p = 0.0043). Infant recipients, IT >4 h, and those bridged medically were associated with higher plateau BNP. Multivariable logistic regression demonstrated IT >4 h independently predicted plateau BNP in the upper quartile (OR 7.1, p = 0.02). No significant change in BNP coincided with rejection (N = 6 patients) without severe hemodynamic compromise. BNP correlated modestly with right atrial pressure (r = 0.4652, p < 0.0001) and pulmonary capillary wedge pressure (r = 0.2660, p < 0.001), but poorly with echocardiogram (r = -0.18, p = 0.003). Trending BNP could help provide insight into how the graft recovers after HT and IT >4 h independently predicted higher plateau BNP and may reflect subtle changes in graft performance.