Background: Heart failure with preserved ejection fraction (HFpEF) is a major health concern. There is a growing recognition of the causal interplay between arterial stiffness and HFpEF. We recently reported that phosphate retention is a trigger for arterial stiffness. This study focuses on whether arterial stiffness due to phosphate retention could be a predictor for HFpEF. Methods: The study subjects were 158 patients (68 males and 90 females, mean age 74.8±11.2). HFpEF was defined according to the guidelines of the ESC 2019. Pulse wave velocity (PWV) and central systolic blood pressure (CSBP) were used as markers for arterial stiffness and afterload, respectively. We measured serum levels of fibroblast growth factor 23 (FGF23) as a marker of phosphate retention. Results: The serum levels of FGF23 had significant relationship with PWV. PWV had significant relationships with LV mass index, plasma BNP levels, and relative wall thickness, e’ and E/e’ (p<0.001, respectively). Multivariate logistic regression analysis revealed that PWV higher values and hypertension were significant predictors for the dependent factor (HFpEF). Conclusions: Arterial stiffness amplified LV afterload, leading to LV concentric hypertrophy and LV diastolic dysfunction. This study presents that arterial stiffness due to phosphate retention, and hypertension are important predictors of HFpEF.

The problem of increasing life expectancy is solved with the help of many medical and social areas. It has been established that piRNAs and miRNAs can significantly modify the expression of protein-coding genes by suppressing the translation process. The aim of this work was to establish the possibility of binding piRNAs and miRNAs with mRNA of the KLOTHO and FGF23 genes, which promote health and increase life expectancy through participation in key metabolic processes. We used the MirTarget program, which determines the quantitative characteristics of complementary interactions of all piRNAs and miRNAs nucleotides with mRNA of the genes. piR-44682, piR-1940042, piR-3008660, piR-3215034, piR-6885965, piR-7980636 and one miRNA (ID00756.3p-miR) binding to the mRNA of the KLOTHO gene were found in one cluster of binding sites (BSs). piRNA-6890096 interacted with the mRNA of KLOTHO gene in a fully complementary manner using only canonical nucleotides. Among 17494 human genes, target genes interacting with five piRNAs that bind to the mRNA of KLOTHO gene were identified. mRNA of the AFF2, BCL2L11, CPT1A, DAZAP1, NDRG3, SKIDA1, WBP4, ZIC5, ZSWIM6 genes interacted with piR-3215034 and piR-6885965, which formed clusters of BSs located in 5'UTR, CDS and 3'UTR. The piR-576442, piR-1501557, piR-1845735, piR-2069834, and piR-3029987 had BSs in the mRNAs of the FGF23 gene, located only in the 3'UTR. It is proposed to use piRNAs and miRNAs as regulators of the expression of KLOTHO and FGF23 anti-aging genes.

To maintain an optimal body content of phosphorus throughout postnatal life, variable phosphate absorption from food must be finely matched with urinary excretion. This amazing feat is accomplished through synchronised phosphate transport by myriads of ciliated cells lining the renal proximal tubules. These respond in real time to changes in the phosphate and composition of the renal filtrate, and to hormonal instructions. How they do this has stimulated decades of research. New analytical techniques, coupled with incredible advances in computer technology, have opened new avenues for investigation at a sub-cellular level. There has been a surge of research into different aspects of the process. These have verified long held beliefs and are also dramatically extending our vision of the intense, integrated, intracellular activity which mediates phosphate absorption. Already, some have indicated new approaches for pharmacological intervention to regulate phosphate in common conditions, including chronic renal failure and osteoporosis, as well as rare inherited biochemical disorders. It is a rapidly evolving field. The aim here is to provide an overview of our current knowledge, to show where it is leading, and where there are uncertainties. Hopefully this will raise questions and stimulate new ideas for further research.