Association Between the Redox State of Human Serum Albumin and Exercise Capacity in Patients With Cardiac Disease

Cardiorespiratory fitness in stroke patients with different activities of daily living levels: a cross-sectional study

Understanding the relationship between cardiorespiratory function (CRF) and activities of daily living (ADL) in stroke patients is essential for improving rehabilitation outcomes. A total of 153 participants were enrolled in this study. Cardiopulmonary exercise was tested at admission. A multivariable linear regression was performed to identify variables associated with peak oxygen uptake (VO2peak). Participants with low ADL exhibited poorer responses to exercise than those with high ADL levels. After adjusting for confounders, the multiple linear regression analysis showed that albumin-to-globulin ratio (AGR) and left ventricular posterior wall thickness (LVPW) were significantly associated with VO2peak in all patients. In the low ADL subgroup, the positive association between AGR and VO2peak was consistent. Conversely, the negative association between LVPW and VO2peak was uncertain. Otherwise, no significant association were found between AGR, LVPW, and VO2peak in the high ADL subgroup. This study provides new insights into the relationship between CRF and ADL in stroke patients, with a focus on ARG and LVPW. Future studies with larger sample sizes are needed to further explore the role of AGR and LVPW in improving the CRF in stroke patients.

Redox state of human serum albumin as a post-discharge prognostic marker in patients hospitalized for heart failure

BACKGROUND

Heart failure (HF) is a global health concern, and oxidative stress has been implicated in its progression. The redox state of human serum albumin, a systemic oxidative biomarker, holds promise as a prognostic marker in HF. This study aimed to investigate the association between the fraction of human mercaptalbumin (fHMA), an indicator of human serum albumin's redox state, and adverse events in HF within a prospective single-hospital-based cohort.

METHODS

We enrolled patients hospitalized for HF and measured fHMA using high-performance liquid chromatography at discharge. The primary endpoint was the composite of HF rehospitalization and all-cause death within one year after discharge.

RESULTS

A total of 221 participants (median age:79 years; 35 % female) were included in the study. Over the course of one year, 26.1 % of the patients experienced HF readmission, while 13.1 % died. The low fHMA group divided by median of fHMA (<57.6 %) showed higher composite outcome rates (41.4 % for the low fHMA vs. 24.6 % for the high fHMA, p = 0.0114). Multivariate analysis, accounting for seven potential confounders, identified low fHMA (adjusted HR: 1.79 [1.03-3.11]) and lower hemoglobin as independent predictors of HF prognosis.

CONCLUSIONS

The findings in this study provide the first evidence that fHMA is a potential novel prognostic biomarker in patients with HF.

A novel chitosan antioxidant bearing sulfhydryl group: Synthesis, characterization and activity assessment

To improve the antioxidant activity, sulfhydryl groups (-SH) were introduced into chitosan. Acylated chitosan derivatives, chitosan cationic salt derivatives, hydroxypropyl trimethylammonium chloride chitosan quaternary ammonium salt (HACC) derivatives and N,N,N-trimethyl chitosan iodine (TMC) derivatives were obtained. The chitosan derivatives were characterized by FTIR and 1H NMR to confirm the successful synthesis. Ellman's reagent was used to determine that the compound contained free sulfhydryl groups. The water solubility and thermal stability of chitosan and derivatives were evaluated. The antioxidant activities of the derivatives were verified, including DPPH radical scavenging activity, superoxide anion radical scavenging activity and reducing power activity. The novel chitosan derivatives showed excellent antioxidant activities. Toxicity assay used L929 cells proved that the derivatives had no significant toxic. The results showed that the chitosan derivatives bearing sulfhydryl groups described in this paper has a certain antioxidant effect, which provides a practical approach for further study of chitosan.

Albumin Redox Modifications Promote Cell Calcification Reflecting the Impact of Oxidative Status on Aortic Valve Disease and Atherosclerosis

Calcific aortic valve disease (CAVD) and coronary artery disease (CAD) are related cardiovascular diseases in which common mechanisms lead to tissue calcification. Oxidative stress plays a key role in these diseases and there is also evidence that the redox state of serum albumin exerts a significant influence on these conditions. To further explore this issue, we used multimarker scores (OxyScore and AntioxyScore) to assess the global oxidative status in patients with CAVD, with and without CAD, also evaluating their plasma thiol levels. In addition, valvular interstitial cells were treated with reduced, oxidized, and native albumin to study how this protein and its modifications affect cell calcification. The differences we found suggest that oxidative status is distinct in CAVD and CAD, with differences in redox markers and thiol levels. Importantly, the in vitro interstitial cell model revealed that modified albumin affects cell calcification, accelerating this process. Hence, we show here the importance of the redox system in the development of CAVD, emphasizing the relevance of multimarker scores, while also offering evidence of how the redox state of albumin influences vascular calcification. These data highlight the relevance of understanding the overall redox processes involved in these diseases, opening the door to new studies on antioxidants as potential therapies for these patients.