Sympathoexcitation in calcineurin inhibitor-induced hypertension: villain or innocent bystander?

Protective effect of dapagliflozin against cyclosporine A-induced nephrotoxicity

This study aimed to reveal the possible protective effect of dapagliflozin (DAPA) against acute kidney damage due to cyclosporine A (CsA). Thirty-two mice with an eight-week-old Balb\c albino strain were divided into four groups: control group, CsA group, DAPA group, and CsA + DAPA group. On day 9 of treatment, the animals were decapitated, and bilateral nephrectomy was performed. Oxidative stress and apoptosis were evaluated with caspase-3 activity, total oxidant status (TOS), total antioxidant status (TAS), malondialdehyde (MDA), myeloperoxidase (MPO), B-cell lymphoma-2 (Bcl-2), and Bcl-2-associated X protein (Bax) in the right kidney resection material. The left kidney resection material was evaluated histopathologically. CsA increased caspase-3 activity, Bax, TOS, MDA, TAS, and MPO levels, and the administration of DAPA with CsA significantly reduced this increase in levels (p < 0.001, p < 0.001, p < 0.001, p < 0.001, p < 0.001, and p < 0.001, respectively). CsA decreased Bcl-2 levels, and administration of CsA + DAPA significantly increased Bcl-2 levels compared with only CsA administration (p < 0.001). Additionally, administration of DAPA significantly reduced the histopathological findings (parenchymal inflammation, hyaline cast formation, vacuolization, and lysis of renal tubular cells) caused by CsA. DAPA reduces oxidative stress, apoptosis, and histopathological damage caused by CsA in renal tissue.

Etiology and management of hypertension in patients with cancer

The pathophysiology of hypertension and cancer are intertwined. Hypertension has been associated with an increased likelihood of developing certain cancers and with higher cancer-related mortality. Moreover, various anticancer therapies have been reported to cause new elevated blood pressure or worsening of previously well-controlled hypertension. Hypertension is a well-established risk factor for the development of cardiovascular disease, which is rapidly emerging as one of the leading causes of death and disability in patients with cancer. In this review, we discuss the relationship between hypertension and cancer and the role that hypertension plays in exacerbating the risk for anthracycline- and trastuzumab-induced cardiomyopathy. We then review the common cancer therapies that have been associated with the development of hypertension, including VEGF inhibitors, small molecule tyrosine kinase inhibitors, proteasome inhibitors, alkylating agents, glucocorticoids, and immunosuppressive agents. When available, we present strategies for blood pressure management for each drug class. Finally, we discuss blood pressure goals for patients with cancer and strategies for assessment and management. It is of utmost importance to maintain optimal blood pressure control in the oncologic patient to reduce the risk of chemotherapy-induced cardiotoxicity and to decrease the risk of long-term cardiovascular disease.

The Advantages of Polymeric Hydrogels in Calcineurin Inhibitor Delivery

In recent years, polymeric hydrogels (PolyHy) have been extensively explored for their applications in biomedicine as biosensors, in tissue engineering, diagnostic processes, and drug release. The physical and chemical properties of PolyHy indicate their potential use in regulating drug delivery. Calcineurin inhibitors, particularly cyclosporine (CsA) and tacrolimus (TAC), are two important immunosuppressor drugs prescribed upon solid organ transplants. Although these drugs have been used since the 1970s to significantly increase the survival of transplanted organs, there are concerns regarding their undesirable side effects, primarily due to their highly variable concentrations. In fact, calcineurin inhibitors lead to acute and chronic toxicities that primarily cause adverse effects such as hypertension and nephrotoxicity. It is suggested from the evidence that the encapsulation of calcineurin inhibitors into PolyHy based on polysaccharides, specifically alginate (Alg), offers effective drug delivery with a stable immunosuppressive response at the in vitro and in vivo levels. This not only may reduce the adverse effects but also would improve the adherence of the patients by the effective preservation of drug concentrations in the therapeutic ranges.

Drug-Induced Hypertension

Untoward side effects of pharmaceuticals can result in considerable morbidity and expense to the health care system. There is likely a sizable fraction of the hypertensive population with disease either induced or exacerbated by polypharmacy. The elevation of blood pressure in drug-induced hypertension occurs through a variety of mechanisms, most notably, sodium and fluid retention, activation of the renin-angiotensin-aldosterone system, alteration of vascular tone, or a combination of these pathways. Recognition of common medications causing drug-induced hypertension is important to effectively control blood pressure. The epidemiology, pathophysiology, and management of these agents are discussed.

Heart rate response to blood pressure variations: sympathetic activation versus baroreflex response in patients with end-stage renal disease

Background

Continuous systolic blood pressure (SBP) and interbeat intervals (IBI) recordings reveal sequences of consecutive beats in which SBP and heart rate change in opposite direction, representing negative feedback baroreflex mechanisms, as well as sequences in which SBP and heart rate change in the same direction (non-baroreflex), believed to represent feedforward control mechanisms. The present study was undertaken to assess the relationship between baroreflex and non-baroreflex sequences in end stage renal insufficiency.

Methodology/Principal Findings

Continuous beat-to-beat SBP and IBI monitoring was performed in patients on chronic hemodialysis (HD, n=72), in age-matched patients after renal transplantation (TX, n=41) and healthy (control) individuals (C, n=34). The proportion of baroreflex and nonbaroreflex episodes and the b coefficients (the regression line slope of SBP-IBI correlation) were determined using a newly developed 1 minute sliding window method, the classical sequence technique and the "Z" coefficient method. Analysis using the 1 minute sliding window showed an increased proportion of baroreflex episodes in controls and HD, and predominance of nonbaroreflex episodes in TX. An increased proportion of nonbaroreflex episodes in TX patients relative to HD was also revealed by the "Z" method. Baroreflex and nonbaroreflex b coefficients obtained by all methods were markedly decreased in HD. This alteration was reversed at least partly in TX. In HD, both baroreflex and nonbaroreflex b coefficients were inversely correlated to age and CRP levels; in TX, the nonbaroreflex b coefficient was influenced by the type of calcineurin inhibitor.

Conclusion/Significance

Renal status affects the contribution of baroreflex and nonbaroreflex mechanisms and the strength of SBP-IBI relationship. The predominant contribution of nonbaroreflex mechanisms in TX may be suggestive of enhanced central sympathetic control. Our data may be relevant for understanding of the pathogenesis and selection of appropriate treatment of post-transplant hypertension.

Hypertension: The Neglected Complication of Transplantation

Arterial hypertension and transplantation are closely linked, and its association may promote impaired graft and overall survival. Since the introduction of calcineurin inhibitors, it is observed in 50–80% of transplanted patients. However, many pathophysiological mechanisms are involved in its genesis. In this review, we intend to provide an updated overview of these mechanisms, dealing with the causes common to all kinds of transplantation and emphasizing special cases with distinct features, and to give a perspective on the pharmacological approach, in order to help clinicians in the management of this frequent complication.

Pathogenesis of calcineurin inhibitor-induced hypertension

This article reviews the current understanding of the mechanisms of calcineurin inhibitor-induced hypertension. Already early after the introduction of cyclosporine in the 1980s, vasoconstriction, sympathetic excitation and sodium retention by the kidney had been shown to play a role in this form of hypertension. The vasoconstrictive effects of calcineurin inhibitors are related to interference with the balance of vasoactive substances, including endothelin and nitric oxide. Until recently, the renal site of the sodium-retaining effect of calcineurin inhibitors was unknown. We and others have shown that calcineurin inhibitors increase the activity of the thiazide-sensitive sodium chloride cotransporter through an effect on the kinases WNK and SPAK. Here, we review the pertinent literature on the hypertensinogenic effects of calcineurin inhibitors, including neural, vascular and renal effects, and we propose an integrated model of calcineurin inhibitor-induced hypertension.