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Abstract Free heme is released from hemoproteins during hemolysis or ischemia reperfusion injury and can be pro‐inflammatory. Most studies on nephrotoxicity of hemolysis‐derived proteins focus on free hemoglobin (fHb) with heme as a prosthetic group. Measurement of heme in its free, non‐protein bound, form is challenging and not commonly used in clinical routine diagnostics. In contrast to fHb, the role of free heme in acute kidney injury (AKI) after cardiopulmonary bypass (CPB) surgery is unknown. Using an apo‐horseradish peroxidase‐based assay, we identified free heme during CPB surgery as predictor of AKI in patients undergoing cardiac valve replacement (n = 37). Free heme levels during CPB surgery correlated with depletion of hemopexin (Hx), a heme scavenger‐protein. In mice, the impact of high levels of circulating free heme on the development of AKI following transient renal ischemia and the therapeutic potential of Hx were investigated. C57BL/6 mice were subjected to bilateral renal ischemia/reperfusion injury for 15 min which did not cause AKI. However, additional administration of free heme in this model promoted overt AKI with reduced renal function, increased renal inflammation, and reduced renal perfusion on functional magnetic resonance imaging. Hx treatment attenuated AKI. Free heme administration to sham operated control mice did not cause AKI. In conclusion, free heme is a predictor of AKI in CPB surgery patients and promotes AKI in transient renal ischemia. Depletion of Hx in CPB surgery patients and attenuation of AKI by Hx in the in vivo model encourage further research on Hx therapy in patients with increased free heme levels during CPB surgery.

Background: Leukocyte telomere length shortening is a characteristic of premature senescence, a process that can be accelerated by oxidative stress. In general, patients with end-stage renal disease undergoing regular hemodialysis (HD) are repeatedly exposed to oxidative stress. Patients undergoing HD tend to have cardiovascular diseases associated with oxidative stress and inflammation. Therefore, we assumed that telomere length is associated with HD vintage and the degree of vascular calcification. Methods: A total of 144 patients undergoing regular HD before kidney transplantation and 62 patients on hemodialysis, but not undergoing kidney transplantation, were enrolled. We measured common laboratory values, such as calcium, phosphate, and hemoglobin levels, and assessed the degree of vascular calcification in the patients. The leukocyte telomere length was measured using reverse transcription polymerase chain reaction, and Spearman correlation was used for correlation analysis. Results: The leukocyte telomere length was negatively associated with age (rho = −0.306, P＜0.01); it was shorter in middle-aged patients than in young patients (13.48 ± 4.80 vs. 15.86 ± 4.51, P

Background: Macrophages play an important role in renal ischemia reperfusion injury, but the functional changes of macrophages under hypoxia/reoxygenation and the related mechanism are unclear and need to be further clarified. Methods: The effects of hypoxia/reoxygenation on functional characteristics of RAW264.7 macrophages were analyzed through the protein expression detection of pro-inflammatory factors TNF-α and CD80, anti-inflammatory factors ARG-1 and CD206. The functional implications of C-X3-C motif chemokine receptor 1(CX3CR1) down-regulation in hypoxic macrophages were explored using small interfering RNA technology. Significance was assessed by the parametric t-test or nonparametric Mann–Whitney test for two group comparisons, and a one-way ANOVA or the Kruskal–Wallis test for multiple group comparisons. Results: Hypoxia/reoxygenation significantly increased the protein expression of M1-related pro-inflammatory factors TNF-α, CD80 and chemokine C-X3-C motif chemokine ligand 1 (CX3CL1)/CX3CR1 and inhibited the protein expression of M2-related anti-inflammatory factors ARG-1 and CD206 in a time-dependent manner in RAW264.7 cells. However, the silencing of CX3CR1 in RAW264.7 cells using specific CX3CR1-siRNA, significantly attenuated the increase in protein expression of TNF-α (P

This study evaluated the bioequivalence of omalizumab, a humanized monoclonal antibody against immunoglobulin-E (IgE), with one of its biosimilar candidates. The study was designed as a randomized, double-blind, parallel-controlled trial. A total of subjects who met the inclusion criteria and did not meet the exclusion criteria were dynamically randomly assigned to receive the test drug or the reference drug with a single subcutaneous injection of 150 mg by the minimization method. The test group and the reference group had similar demographic characteristics and baseline characteristics of total IgE. The 90% confidence interval of the geometric average ratio of the area under the serum concentration-time curve from the time 0 to the time of last quantifiable concentration, the area under the serum concentration curve from time 0 to infinity, and the maximum observed serum concentration between the 2 groups were within 80%-125%, showing bioequivalence. The changing trend of total and free IgE in the 2 groups was similar after administration, proving the pharmacodynamic similarity. The 2 groups had no significant difference in the positive rate of antidrug antibodies, and the total positive rate of neutralizing antibodies was 0. The incidence of treatment-emergent adverse events and treatment-related adverse events were similar between the 2 groups, with no serious adverse events. This study shows that the test drug had similar pharmacokinetics, immunogenicity, and safety to the reference omalizumab in healthy male subjects., (© 2023, The American College of Clinical Pharmacology.)

Objective: To explore the association of ATG5 gene polymorphisms with autoimmune thyroid diseases (AITDs) including Hashimoto's thyroiditis (HT) and Graves' illness (GD) as well as their clinical features., Methods: rs6568431, rs548234, and rs6937876 were selected to investigate the correlation of single-nucleotide polymorphisms of ATG5 gene with AITDs. Their frequencies in 824 AITD patients, including 271 HT patients and 553 GD patients, and 764 healthy controls were tested using both ligase detection reaction and multiplex polymerase chain reaction., Results: Allele A frequency of rs6568431 in AITDs patients ( p = 0.016, OR = 1.201, 95% CI = 1.034 - 1.394) and allele G frequency of rs6937876 in AITDs patients ( p = 0.009, OR = 1.223, 95% CI = 1.052 - 1.422) and in GD patients ( p = 0.009, OR = 1.247, 95% CI = 1.056 - 1.473) were significantly higher than those in the healthy controls. The frequency of G allele ( p = 5.42E - 18, OR = 0.242, 95% CI = 0.173 - 0.339) of rs6937876 was significantly higher in GD patients with ophthalmopathy. However, no relationship was found between family history, age onset, and the three SNPs., Conclusion: The study is the first to reveal the association between AITDs and ATG5 polymorphisms, and ATG5 gene is considered as a predisposing gene to AITDs, especially GDs., Competing Interests: The authors declare no conflict of interest and are responsible for the content of this paper., (Copyright © 2022 Wen Wang et al.)

Background: To date, studies have shown that polymorphisms in an autophagy-related gene, IRGM , are linked with different diseases, especially autoimmune diseases. The present study aimed to examine the roles of IRGM polymorphisms in autoimmune thyroid diseases (AITD)., Methods: Three polymorphisms in IRGM gene (rs10065172, rs4958847, and rs13361189) were genotyped in 1569 participants (488 with Graves' disease, 292 with Hashimoto's thyroiditis, and 789 healthy controls) using PCR-based ligase detection reaction method. Gene-disease associations were evaluated for the three SNPs., Results: T allele of rs10065172, A allele of rs4958847, and C allele of rs13361189 were all higher in Graves' disease patients than controls, and the ORs were OR = 1.207 ( P = 0.022), OR = 1.207 ( P = 0.027), and OR = 1.200 ( P = 0.027), respectively. After adjusting for sex and age, rs10065172 and rs13361189 were still associated with GD under both the allele model and dominant model, and the adjusted ORs for rs10065172 were 1.20 ( P = 0.033) and 1.33 ( P = 0.024), while the adjusted ORs for rs13361189 were 1.19 ( P = 0.042) and 1.33 ( P = 0.026), respectively. No significant difference was found between Hashimoto's thyroiditis patients and controls. Haplotype analysis found that CTA frequency was distinguishingly higher in Graves' disease patients (OR = 1.195, P = 0.030). The frequency of TCG haplotype was distinguishingly lower in AITD and Graves' disease patients (OR = 0.861, P = 0.044; OR = 0.816, P = 0.017)., Conclusions: Our study reveals IRGM as a susceptibility gene of AITD and Graves' disease for the first time.

Here, we aimed to compare the unstable gait caused by unilateral vestibular hypofunction (UVH) with the normal gait. Twelve patients with UVH and twelve age-matched control subjects were enrolled in the study. Thirty-four markers were attached to anatomical positions of each participant, and a three-dimensional (3D) motion analysis system was used to capture marker coordinates as the participants walked on a treadmill. The mean standard deviation of the rotation angles was used to represent gait variability. To explore gait stability, local dynamic stability was calculated from the trunk trajectory. The UVH group had wider step width and greater variability of roll rotation at the hip than the control group ( P < 0.05). Also, the UVH group had lower local dynamic stability in the medial-lateral (ML) direction than the control group ( P < 0.05). By linear regression analysis, we identified a linear relationship between the short-term Lyapunov exponent and vestibular functional asymmetry. The result implies that UVH-induced asymmetry can increase posture variability and gait instability. This study demonstrates the potential for using kinematic parameters to quantitatively evaluate the severity of vestibular functional asymmetry. Further studies will be needed to explore the clinical effectiveness of such approaches.

Cardiac fibroblasts (CFs) play a key role in cardiac fibrosis by regulating the balance between extracellular matrix synthesis and breakdown. Although phosphatase and tensin homologue on chromosome 10 (PTEN) has been found to play an important role in cardiovascular disease, it is not clear whether PTEN is involved in functional regulation of CFs. In the present study, PTEN was overexpressed in neonatal rat CFs via recombinant adenovirus-mediated gene transfer. The effects of PTEN overexpression on cell-cycle progression and angiotensin II- (Ang II-) mediated regulation of collagen metabolism, synthesis of matrix metalloproteinases, and Akt/P27 signaling were investigated. Compared with uninfected cells and cells infected with green fluorescent protein-expressing adenovirus (Ad-GFP), cells infected with PTEN-expressing adenovirus (Ad-PTEN) significantly increased PTEN protein and mRNA levels in CFs ( P < 0.05). The proportion of CFs in the G1/S cell-cycle phase was significantly higher for PTEN-overexpressing cells. In addition, Ad-PTEN decreased mRNA expression and the protein synthesis rate of collagen types I and III and antagonized Ang II-induced collagen synthesis. Overexpression of PTEN also decreased Ang II-induced matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-1 (TIMP-1) production as well as gelatinase activity. Moreover, Ad-PTEN decreased Akt expression and increased P27 expression independent of Ang II stimulation. These results suggest that PTEN could regulate its functional effects in neonatal rat CFs partially via the Akt/P27 signaling pathway., Competing Interests: The authors declare that there is no conflict of interests regarding the publication of this paper.