Distinct transcriptomic profile of small arteries of hypertensive patients with chronic kidney disease identified miR-338-3p targeting GPX3 and PTPRS

Relationship between serum level of miR-338-3p and miR-105-3p and bone metabolic markers in patients with diabetes nephropathy

OBJECTIVES

Diabetic nephropathy (DN) is one of the most common and serious complications of diabetes. The purpose of this study was to explore the relationship between serum microRNA-338-3p (miR-338-3p) and miR-105-3p and bone metabolic markers in patients with DN at different stages.

METHODS

A total of 153 patients diagnosed and treated in the Department of Nephrology from July 2020 to October 2021 were selected as the study objects. According to the staging criteria of diabetic nephropathy and 24-h urinary albumin quantitative level, the patients were divided into control group (35 cases), microalbuminuria group (37 cases), clinical stage albuminuria group (27 cases) and renal failure group (54 cases). Gene expressions were measured by real-time fluorescence quantitative PCR. The correlation was analyzed by Spearman. Serum miR-338-3p and miR-150-5p in the prediction of renal failure in DN was analyzed by ROC curve.

RESULTS

The levels of urinary albumin and serum creatinine were markedly increased with the increase of DN stage (p < 0.05). Compared with the microalbuminuria group, the expression levels of serum miR-383-3p, serum miR-105-3p, 25(OH)-D, BGP and PINP were obviously decreased, but the expression of parathyroid hormone (PTH) and type I collagen (β-CTX) was largely increased in clinical proteinuria group (p < 0.05). Compared with the clinical proteinuria group, the expression levels of serum miR-383-3p, serum miR-105-3p, 25(OH)-D, BGP and PINP were largely decreased, but the expression of PTH and β-CTX was obviously increased in the renal failure group (p < 0.05). Spearman correlation results showed that serum expressions of miR-383-3p and miR-105-3p were negatively correlated with PTH and β-CTX, and positively correlated with 25(OH)-D, BGP and PINP (p < 0.05). ROC curve analysis showed that the AUC of serum miR-338-3p and miR-150-5p was 0.896 with the specificity and sensitivity of 96.66% and 73.47%, which had certain predictive value for the occurrence of renal failure in DN.

CONCLUSIONS

The expression levels of serum miR-383-3p and miR-105-3p were significantly correlated with bone metabolism markers. The combined test can provide new ideas and insights for the clinical treatment of osteoporosis in DN.

Insights into the Role of Glutathione Peroxidase 3 in Non-Neoplastic Diseases

Reactive oxygen species (ROSs) are byproducts of normal cellular metabolism and play pivotal roles in various physiological processes. Disruptions in the balance between ROS levels and the body's antioxidant defenses can lead to the development of numerous diseases. Glutathione peroxidase 3 (GPX3), a key component of the body's antioxidant system, is an oxidoreductase enzyme. GPX3 mitigates oxidative damage by catalyzing the conversion of hydrogen peroxide into water. Beyond its antioxidant function, GPX3 is vital in regulating metabolism, modulating cell growth, inducing apoptosis and facilitating signal transduction. It also serves as a significant tumor suppressor in various cancers. Recent studies have revealed aberrant expression of GPX3 in several non-neoplastic diseases, associating it with multiple pathological processes. This review synthesizes the current understanding of GPX3 expression and regulation, highlighting its extensive roles in noncancerous diseases. Additionally, this paper evaluates the potential of GPX3 as a diagnostic biomarker and explores emerging therapeutic strategies targeting this enzyme, offering potential avenues for future clinical treatment of non-neoplastic conditions.

Chronic TNF exposure induces glucocorticoid-like immunosuppression in the alveolar macrophages of aged mice that enhances their susceptibility to pneumonia

Chronic low-grade inflammation, particularly elevated tumor necrosis factor (TNF) levels, occurs due to advanced age and is associated with greater susceptibility to infection. One reason for this is age-dependent macrophage dysfunction (ADMD). Herein, we use the adoptive transfer of alveolar macrophages (AM) from aged mice into the airway of young mice to show that inherent age-related defects in AM were sufficient to increase the susceptibility to Streptococcus pneumoniae, a Gram-positive bacterium and the leading cause of community-acquired pneumonia. MAPK phosphorylation arrays using AM lysates from young and aged wild-type (WT) and TNF knockout (KO) mice revealed multilevel TNF-mediated suppression of kinase activity in aged mice. RNAseq analyses of AM validated the suppression of MAPK signaling as a consequence of TNF during aging. Two regulatory phosphatases that suppress MAPK signaling, Dusp1 and Ptprs, were confirmed to be upregulated with age and as a result of TNF exposure both ex vivo and in vitro. Dusp1 is known to be responsible for glucocorticoid-mediated immune suppression, and dexamethasone treatment increased Dusp1 and Ptprs expression in cells and recapitulated the ADMD phenotype. In young mice, treatment with dexamethasone increased the levels of Dusp1 and Ptprs and their susceptibility to infection. TNF-neutralizing antibody reduced Dusp1 and Ptprs levels in AM from aged mice and reduced pneumonia severity following bacterial challenge. We conclude that chronic exposure to TNF increases the expression of the glucocorticoid-associated MAPK signaling suppressors, Dusp1 and Ptprs, which inhibits AM activation and increases susceptibility to bacterial pneumonia in older adults.