Drug-related hypertension and resistance to antihypertensive treatment: a call for action

Myocardial Protection and Current Cancer Therapy: Two Opposite Targets with Inevitable Cost

Myocardial protection against ischemia/reperfusion injury (IRI) is mediated by various ligands, activating different cellular signaling cascades. These include classical cytosolic mediators such as cyclic-GMP (c-GMP), various kinases such as Phosphatydilinositol-3- (PI3K), Protein Kinase B (Akt), Mitogen-Activated-Protein- (MAPK) and AMP-activated (AMPK) kinases, transcription factors such as signal transducer and activator of transcription 3 (STAT3) and bioactive molecules such as vascular endothelial growth factor (VEGF). Most of the aforementioned signaling molecules constitute targets of anticancer therapy; as they are also involved in carcinogenesis, most of the current anti-neoplastic drugs lead to concomitant weakening or even complete abrogation of myocardial cell tolerance to ischemic or oxidative stress. Furthermore, many anti-neoplastic drugs may directly induce cardiotoxicity via their pharmacological effects, or indirectly via their cardiovascular side effects. The combination of direct drug cardiotoxicity, indirect cardiovascular side effects and neutralization of the cardioprotective defense mechanisms of the heart by prolonged cancer treatment may induce long-term ventricular dysfunction, or even clinically manifested heart failure. We present a narrative review of three therapeutic interventions, namely VEGF, proteasome and Immune Checkpoint inhibitors, having opposing effects on the same intracellular signal cascades thereby affecting the heart. Moreover, we herein comment on the current guidelines for managing cardiotoxicity in the clinical setting and on the role of cardiovascular confounders in cardiotoxicity.

What Is or What Is Not a Risk Factor for Arterial Hypertension? Not Hamlet, but Medical Students Answer That Question

Hypertension is a leading cause of cardiovascular disease and premature death worldwide. The most important method of preventing hypertension is social awareness of its causes. An important role in educating society about hypertension is played by medical personnel. The study involved 327 students of medicine representing all years of study. The study used a proprietary questionnaire containing test questions about knowledge of the causes of hypertension (classical and non-classical factors), as well as questionable and false risk factors for the disease. The students’ knowledge of the complications of hypertension was also assessed. Most of the students rated their knowledge about hypertension as good. Classical risk factors for hypertension were identified by students in all years of study: I–III and IV–VI. Non-classical risk factors for hypertension were less often identified by the students. The students almost unanimously indicated that the complications of hypertension include heart failure, heart attack, stroke, aortic aneurysm, kidney failure, atherosclerosis, eye diseases and worse prognosis in COVID-19. Students’ knowledge of the causes of hypertension increased during medical studies. The knowledge of the respondents about classical risk factors for hypertension was extensive, whereas knowledge of non-classical risk factors it was insufficient. Most of the respondents were well aware of the complications of hypertension. Some students identified some factors incorrectly as increasing the risk of hypertension. Emphasis should be placed on the dissemination of knowledge about non-classical hypertension risk factors to medical students.

[Antidepressive agents and hypertension: A case/no-case study in French pharmacovigilance database]

INTRODUCTION

Drug-induced hypertension was described with several pharmacological classes. The association between hypertension and antidepressant drugs (AD) is controversial. The objective of this study was to evaluate the link between hypertension and ADs.

MATERIALS AND METHODS

A retrospective disproportionality analysis from observations consecutively reported to the French pharmacovigilance database between 1985 and 2020 was performed. The relationship between the suspected ADs and the occurrence of hypertension was assessed by calculating the reporting odds ratio (ROR) in a case/non-case design. A negative (paracetamol) and a positive (celecoxib) control were used to validated this disproportionality method.

RESULTS

We compared 6725 cases (including 464 AD-related cases) to 789,483 non-cases (including 56,440 AD-related cases). The reporting of hypertension was significantly associated with serotonin/norepinephrine reuptake inhibitors (SNRI) (ROR 1.43, 95 % CI 1.26-1.64) and monoamine oxidase inhibitors (MAOI) (ROR 6.41, 95 % CI 4.25-9.67) but not with other ADs classes. Concerning ADs analyzed independently of their AD class, a significant signal was observed with many SNRIs (duloxetin, milnacipran and venlafaxin) and with all MAOIs (moclobemide, iproniazide) (ROR between 2.04 and 17.93) but not with others ADs. The ROR value of positive (celecoxib) and negative (paracetamol) controls were ROR=1.53; IC95 %=1.04-2.26 and ROR=0.72; IC95 %=0.65-0.80, respectively.

CONCLUSION

We found a significant association between development or worsening of hypertension and SNRIs and MAOIs but not with others ADs, in this study performed in real conditions of life. It is therefore advisable to remain cautious when prescribing ADs and to check systematically for hypertension.

Clinical Efficacy and Safety of Angiogenesis Inhibitors: Sex Differences and Current Challenges

Vasoactive molecules, such as vascular endothelial growth factor (VEGF) and endothelins, share cytokine-like activities and regulate endothelial cell (EC) growth, migration and inflammation. Some endothelial mediators and their receptors are targets for currently approved angiogenesis inhibitors, drugs that are either monoclonal antibodies raised towards VEGF, or inhibitors of vascular receptor protein kinases and signaling pathways. Pharmacological interference with the protective functions of ECs results in a similar spectrum of adverse effects. Clinically, the most common side effects of VEGF signaling pathway inhibition include an increase in arterial pressure, left ventricular (LV) dysfunction ultimately causing heart failure, and thromboembolic events, including pulmonary embolism, stroke, and myocardial infarction. Sex steroids such as androgens, progestins, and estrogen and their receptors (ERα, ERβ, GPER; PR-A, PR-B; AR) have been identified as important modifiers of angiogenesis, and sex differences have been reported for anti-angiogenic drugs. This review article discusses the current challenges clinicians are facing with regard to angiogenesis inhibitor treatments, including the need to consider sex differences affecting clinical efficacy and safety. We also propose areas for future research taking into account the role of sex hormone receptors and sex chromosomes. Development of new sex-specific drugs with improved target and cell-type selectivity likely will open the way personalized medicine in men and women requiring antiangiogenic therapy and result in reduced adverse effects and improved therapeutic efficacy.

Dose-dependent subacute cardiovascular effects of modafinil in rats

Modafinil is used for the treatment of various sleep disorders; however, its usage among healthy individuals is also increasing. There are a limited number of cardiovascular side effects, including ischemic T-wave changes, dyspnea, hypertension, and tachycardia in the literature. Our research aimed to investigate the dose-dependent subacute cardiovascular effects of modafinil in rats. Thirty-two rats were randomly and equally assigned to a control group (vehicle-treated for 14 days), a subacute low-dose group (SALD, 10 mg/kg for 14 days), a subacute moderate-dose group (SAMD, 100 mg/kg for 14 days), and a subacute high-dose group (SHD, 600 mg/kg for 14 days). The cardiovascular effects of modafinil were evaluated using hemodynamic, biochemical, electrocardiographic, electrophysiologic, and histopathologic parameters. In terms of hemodynamic parameters, heart rate, and systolic/diastolic/mean blood pressure levels, electrophysiological parameters did not reach statistical significance among the groups (p > 0.05). The incidence of T-wave negativity in SAMD and SAHD groups was 25 and 37.5%, respectively. Moreover, one rat per group was affected by an atrioventricular blockage. Malondialdehyde, superoxide dismutase, catalase, and reduced glutathione levels in the heart and vascular tissues, serum troponin-I, and creatine kinase levels were similar between the modafinil-administered groups and the control group (p > 0.05); this indicates that modafinil activated neither oxidative stress nor antioxidant pathway. Also, there was no difference in histopathological parameters between groups (p > 0.05). Supratherapeutic doses of modafinil may have the potential to cause ischemic cardiac damage and atrioventricular blockage, despite inconsistency with literature findings; however, this does not pertain to hemodynamic changes.

Drug-induced endocrine blood pressure elevation

Patients with uncontrolled hypertension are at risk for cardiovascular complications. The majority of them suffers from unidentified forms of hypertension and a fraction has so-called secondary hypertension with an identifiable cause. The patient's medications, its use of certain herbal supplements and over-the-counter agents represent potential causal factors for secondary hypertension that are often overlooked. The current review focuses on drugs that are likely to elevate blood pressure by affecting the human endocrine system at the level of steroid synthesis or metabolism, mineralocorticoid receptor activity, or by affecting the catecholaminergic system. Drugs with known adverse effects but where benefits outweigh their risks, drug candidates and market withdrawals are reviewed. Finally, potential therapeutic strategies are discussed.

[Hypertension associated with paraparesis of the lower limbs revealing an adrenal adenoma]

Cushing's syndrome is a rare cause of high blood pressure. The originally adrenal cause is found in 15% of cases. We describe the case of a patient with hypertension associated with paraparesis of the lower limbs revealing a Cushing syndrome due to a left adrenal adenoma. A 23-year-old man consults for a paraparesis of the lower limbs. The highlighting of an arterial high blood pressure led to the realization of complementary examinations. Computed tomography of the abdomen shows a left adrenal mass. Chirurgical excision of the mass was performed and histological examination concluded with adrenal adenoma. After intervention, the patient normalized his blood pressure with 3 years of follow up. This case illustrates a form of endocrine hypertension of adrenal origin and the need for a careful clinical examination during the discovery of hypertension in the young subject in order to carry out adequate balance sheets to search for a curable cause of secondary hypertension.

MANAGEMENT OF ENDOCRINE DISEASE: Risk of overtreatment in patients with adrenal insufficiency: current and emerging aspects

The effects of long-term replacement therapy of adrenal insufficiency (AI) are still a matter of controversy. In fact, the established glucocorticoid replacement regimens do not completely reproduce the endogenous hormonal production and the monitoring of AI treatment may be a challenge for the lack of reliable clinical and biochemical markers. Consequently, several AI patients are frequently exposed to relative glucocorticoid excess potentially leading to develop chronic complications, such as diabetes mellitus, dyslipidemia, hypertension and fragility fractures with consequent impaired QoL and increased mortality risk. This review deals with the pathophysiological and clinical aspects concerning the over-replacement therapy of primary and secondary AI.

Clinical characteristics, target organ damage and associate risk factors of resistant hypertension determined by ambulatory blood pressure monitoring in patients aged ≥ 80 years

OBJECTIVES

To investigate clinical characteristics, target organ damage, and the associated risk factors of the patients aged ≥ 80 years with true resistant hypertension (RH).

METHODS

Patients aged ≥ 80 years with hypertension (n = 1163) were included in this study. The included participants attended a structured clinical examination and an evaluation of RH was carried out. The prevalence, clinical characteristics and target organ damage of patients with RH were assessed. The associated clinical risk factors were analyzed by using logistic regression.

RESULTS

The prevalence of RH diagnosis by 24-h ambulatory blood pressure monitoring assessment was 21.15%. End-diastolic left ventricular internal dimension, left ventricular mass index as well as prevalence of left ventricular hypertrophy were significantly greater in patients with RH than in control group. The common carotid artery intimal media thickness, carotid walls thickness, common carotid artery diameter and relative wall thickness were significant greater in RH group than in control. A relatively higher level of creatinine, estimated glomerular filtration rate, microalbuminuria and retinal changes was found in RH group than in control. A multivariate analysis showed that patients with a history of diabetes, higher body mass index (BMI) and lipid profiles were independent risk factors of RH.

CONCLUSIONS

The prevalence of RH in patients aged ≥ 80 years was within the range of reported rates of the general population. Subjects with RH diagnosis showed a higher occurrence of target organ damage than patients with well controlled blood pressure. Patients with diabetes, higher BMI and serum lipid profiles were independent risk factors for RH in patients aged ≥ 80 years.

Women, Hypertension, and the Systolic Blood Pressure Intervention Trial

Hypertension accounts for approximately 1 in 5 deaths in American women and is the major contributor to many comorbid conditions. Although blood pressure lowering reduces cardiovascular disease outcomes, considerable uncertainty remains on best management in women. Specifically, female blood pressure treatment goals have not been established, particularly among older and African American and Hispanic women, for whom hypertension prevalence, related adverse outcomes, and poor control rates are high. The Systolic Blood Pressure Intervention Trial (SPRINT) planned to clarify optimal blood pressure management in both sexes. Although confirming that a lower blood pressure goal is generally better, because female enrollment and event rates were low and follow-up shortened, outcomes differences in women were not statistically significant. Thus optimal blood pressure goals for women have not been established with the highest evidence. This review addresses SPRINT's significance and key remaining knowledge gaps in optimal blood pressure management to improve women's health.

[Prevalence of true resistant hypertension among uncontrolled hypertensive patients referred to a tertiary health care center]

OBJECTIVES

Estimate the prevalence of resistant hypertension (rHTN) in uncontrolled hypertensive treated patients referred to a tertiary care center specialized for hypertension management.

METHODS

The study was prospective observational. Between January 2013 and April 2015, we recruited hypertensive treated patients, 18years age or older, under antihypertensive drugs since at least 12months, and referred to the hypertension unit of Tizi-ouzou university hospital for uncontrolled hypertension. rHTn was defined as an office blood pressure≥140mmHg despite a triple therapy including renin angiotensin system blockers, calcium antagonists and diuretics at optimal doses, since at least 4weeks.

RESULTS

We screened 2367 patients with a mean age of 61.1±11.2years and 64.2% of men. Eight hundred forty-three (35.6%) patients had suboptimal treatment, 364 (15.4%) a poor adherence to treatment and 202 (8.5%) a white-coat effect. An excessive salt intake and a drug-related hypertension were identified in 281 (11.9%) and 36 (1.5%) patients, respectively. A secondary cause of hypertension was diagnosed in 468 (19.8%) subjects. Finally, only 173 patients showed a true rHTN requiring four drugs or more and its prevalence was 7.3% (CI 95%: 6.3-8.3).

CONCLUSION

Less than one patient from ten referred in our center for uncontrolled hypertension had a true rHTN, and more than fifty percent of patients had pseudo-resistance. Most of patients with seemingly rHTN can reach blood pressure target provided they undergo thorough work up and care by a specialized team.

The hypertension of Cushing's syndrome: controversies in the pathophysiology and focus on cardiovascular complications

Cushing's syndrome is associated with increased mortality, mainly due to cardiovascular complications, which are sustained by the common development of systemic arterial hypertension and metabolic syndrome, which partially persist after the disease remission. Cardiovascular diseases and hypertension associated with endogenous hypercortisolism reveal underexplored peculiarities. The use of exogenous corticosteroids also impacts on hypertension and cardiovascular system, especially after prolonged treatment. The mechanisms involved in the development of hypertension differ, whether glucocorticoid excess is acute or chronic, and the source endogenous or exogenous, introducing inconsistencies among published studies. The pleiotropic effects of glucocorticoids and the overlap of the several regulatory mechanisms controlling blood pressure suggest that a rigorous comparison of in-vivo and in-vitro studies is necessary to draw reliable conclusions. This review, developed during the first ‘Altogether to Beat Cushing's syndrome’ workshop held in Capri in 2012, evaluates the most important peculiarities of hypertension associated with CS, with a particular focus on its pathophysiology. A critical appraisal of most significant animal and human studies is compared with a systematic review of the few available clinical trials. A special attention is dedicated to the description of the clinical features and cardiovascular damage secondary to glucocorticoid excess. On the basis of the consensus reached during the workshop, a pathophysiology-oriented therapeutic algorithm has been developed and it could serve as a first attempt to rationalize the treatment of hypertension in Cushing's syndrome.

Drug induced hypertension--An unappreciated cause of secondary hypertension

Most patients with hypertension have essential hypertension or well-known forms of secondary hypertension, such as renal disease, renal artery stenosis, or common endocrine diseases (hyperaldosteronism or pheochromocytoma). Physicians are less aware of drug induced hypertension. A variety of therapeutic agents or chemical substances may increase blood pressure. When a patient with well controlled hypertension is presented with acute blood pressure elevation, use of drug or chemical substance which increases blood pressure should be suspected. Drug-induced blood pressure increases are usually minor and short-lived, although rare hypertensive emergencies associated with use of certain drugs have been reported. Careful evaluation of prescription and non-prescription medications is crucial in the evaluation of the hypertensive individual and may obviate the need for expensive and unnecessary evaluations. Discontinuation of the offending agent will usually achieve adequate blood pressure control. When use of a chemical agent which increases blood pressure is mandatory, anti-hypertensive therapy may facilitate continued use of this agent. We summarize the therapeutic agents or chemical substances that elevate blood pressure and their mechanisms of action.

Steroid Anti-Inflammatory Effects Did Not Improve Organ Quality in Brain-Dead Rats

Effect of glucocorticoid administration on improving the outcomes of kidney and liver allografts has not been clearly elucidated. This study investigated the effect of prednisolone administration after onset of brain death (BD) on kidney and liver in a controlled rat model of BD. BD was induced in rats by inflating an epidurally placed balloon catheter. Animals were treated with saline or prednisolone (5, 12.5, or 22.5 mg/kg) one hour after the onset of BD. After 4 hours of BD, experiments were terminated and serum and tissues were collected. Tissue gene and protein expression were measured for markers of inflammation, apoptosis, and cellular stress response markers. Prednisolone caused a reduction of plasma levels of IL-6, while the tissue expression of IL-6, IL-1β, and MCP-1 in both kidney and liver were also reduced. Creatinine plasma levels, complement (C3) expression, HSP-70, HO-1, Bcl2/BAX ratio, and PMN influx did not significantly change in kidney nor liver. Plasma AST and LDH levels were increased in the prednisolone treated group. Our results demonstrate prednisolone can has an anti-inflammatory effect mediated through reducing serum circulating cytokines. However, this anti-inflammatory effect does not translate into improved kidney function and indeed was associated with increased liver injury markers.

Our own worst enemy: pharmacologic mechanisms of hypertension

Drug-induced hypertension is often an unrecognized cause of resistant or secondary hypertension. It is defined as hypertension resulting from the unintended effect of a drug or from a drug's antagonistic effect on antihypertensive medications. The main mechanisms of drug-induced hypertension, when categorized broadly, include volume retention and sympathomimetic effects. These mechanisms along with management strategies will be further discussed in this article.

Drug therapy for the patient with resistant hypertension

ABSTRACT 

Resistant hypertension is associated with high morbidity and mortality. Resistant hypertension is defined as blood pressure above targets despite treatment with at least three antihypertensive drugs in adequate dose and combination. Nonadherence is a frequent cause of uncontrolled hypertension and can be improved by providing fixed dose (of two or three agents) single pill combination. Triple combination of the most widely used antihypertensive agents (renin–angiotensin–aldosterone system antagonists, calcium channel blockers and diuretics) is a safe and effective therapy. Fourth line therapy is the use of an aldosterone antagonist. Renal denervation and baroreceptor stimulation can be considered in patients who remained uncontrolled despite optimal medical therapy.

Mineralocorticoid Receptor Antagonists Therapy in Resistant Hypertension: Time to Implement Guidelines!

Despite the availability of anti-hypertensive medications with increasing efficacy up to 50% of hypertensive patients have blood pressure levels (BP) not at the goals set by international societies. Some of these patients are either not optimally treated or are non-adherent to the prescribed drugs. However, a proportion, despite adequate treatment, have resistant hypertension (RH), which represents an important problem in that it is associated to an excess risk of cardiovascular events. Notwithstanding a complex pathogenesis, an abundance of data suggests a key contribution for the mineralocorticoid receptor (MR) in RH, thus fostering a potential role for its antagonists in RH. Based on these premises randomized clinical trials aimed at testing the efficacy of MR antagonists (MRAs) in RH patients have been completed. Overall, they demonstrated the efficacy of MRAs in reducing BP and surrogate markers of target organ damage, such as microalbuminuria, either compared to placebo or to other drugs. In summary, owing to the key role of the MR in the pathogenesis of RH and on the proven efficacy of MRAs we advocate their inclusion as an essential component of therapy in patients with presumed RH. Conversely, we propose that RH should be diagnosed only in patients whose BP values show to be resistant to an up-titrated dose of these drugs.

A novel KCNJ5-insT149 somatic mutation close to, but outside, the selectivity filter causes resistant hypertension by loss of selectivity for potassium

CONTEXT

Understanding the function of the KCNJ5 potassium channel through characterization of naturally occurring novel mutations is key for dissecting the mechanism(s) of autonomous aldosterone secretion in primary aldosteronism.

OBJECTIVE

We sought for such novel KCNJ5 channel mutations in a large database of patients with aldosterone-producing adenomas (APAs).

METHODS

We discovered a novel somatic c.446insAAC insertion, resulting in the mutant protein KCNJ5-insT149, in a patient with severe drug-resistant hypertension among 195 consecutive patients with a conclusive diagnosis of APA, 24.6% of whom showed somatic KCNJ5 mutations. By site-directed mutagenesis, we created the mutated cDNA that was transfected, along with KCNJ3 cDNA, in mammalian cells. We also localized CYP11B2 in the excised adrenal gland with immunohistochemistry and immunofluorescence using an antibody specific to human CYP11B2. Whole-cell patch clamp recordings, CYP11B2 mRNA, aldosterone measurement, and molecular modeling were performed to characterize the novel KCNJ5-insT149 mutation.

RESULTS

Compared with wild-type and mock-transfected adrenocortical cells, HAC15 cells expressing the mutant KCNJ5 showed increased CYP11B2 expression and aldosterone secretion. Mammalian cells expressing the mutated KCNJ5-insT149 channel exhibited a strong Na(+) inward current and, in parallel, a substantial rise in intracellular Ca(2+), caused by activation of voltage-gated Ca(2+) channels and reduced Ca(2+) elimination by Na(+)/Ca(2+) exchangers, as well as an increased production of aldosterone.

CONCLUSIONS

This novel mutation shows pathological Na(+) permeability, membrane depolarization, raised cytosolic Ca(2+), and increased aldosterone synthesis. Hence, a novel KCNJ5 channelopathy located after the pore α-helix preceding the selectivity filter causes constitutive secretion of aldosterone with ensuing resistant hypertension in a patient with a small APA.

Concentration addition, independent action and generalized concentration addition models for mixture effect prediction of sex hormone synthesis in vitro

Humans are concomitantly exposed to numerous chemicals. An infinite number of combinations and doses thereof can be imagined. For toxicological risk assessment the mathematical prediction of mixture effects, using knowledge on single chemicals, is therefore desirable. We investigated pros and cons of the concentration addition (CA), independent action (IA) and generalized concentration addition (GCA) models. First we measured effects of single chemicals and mixtures thereof on steroid synthesis in H295R cells. Then single chemical data were applied to the models; predictions of mixture effects were calculated and compared to the experimental mixture data. Mixture 1 contained environmental chemicals adjusted in ratio according to human exposure levels. Mixture 2 was a potency adjusted mixture containing five pesticides. Prediction of testosterone effects coincided with the experimental Mixture 1 data. In contrast, antagonism was observed for effects of Mixture 2 on this hormone. The mixtures contained chemicals exerting only limited maximal effects. This hampered prediction by the CA and IA models, whereas the GCA model could be used to predict a full dose response curve. Regarding effects on progesterone and estradiol, some chemicals were having stimulatory effects whereas others had inhibitory effects. The three models were not applicable in this situation and no predictions could be performed. Finally, the expected contributions of single chemicals to the mixture effects were calculated. Prochloraz was the predominant but not sole driver of the mixtures, suggesting that one chemical alone was not responsible for the mixture effects. In conclusion, the GCA model seemed to be superior to the CA and IA models for the prediction of testosterone effects. A situation with chemicals exerting opposing effects, for which the models could not be applied, was identified. In addition, the data indicate that in non-potency adjusted mixtures the effects cannot always be accounted for by single chemicals.

Clinical situations associated with difficult-to-control hypertension

There is no doubt that patients with high blood pressure (BP) are at higher cardiovascular and death risk than those subjects whose BP levels are below the admitted normal threshold. However, most of the epidemiological surveys show that BP is uncontrolled in more than fifty percent of hypertensive subjects. There are several reasons that can justify this lack of hypertension control, some of them depending on the patient, such as therapeutic adherence, or some related to the doctor, due to therapeutic inertia or reluctance to increment the number and doses of antihypertensive drugs. Sometimes the efficacy or adverse effects related to the antihypertensive drugs underlie the uncontrolled hypertension. And, finally, there are some clinical conditions that are associated with difficult-to-control hypertension. Among them, comorbidities such as diabetes, obesity, obstructive sleep apnoea syndrome or chronic kidney disease, but also drug-related hypertension or resistant hypertension. In this article we review the epidemiology and the conditions which are related to poorly controlled hypertension and that can explain why hypertension may become difficult-to-treat.

Therapy of adrenal insufficiency: an update

Adrenal insufficiency may be caused by the destruction or altered function of the adrenal gland with a primary deficit in cortisol secretion (primary adrenal insufficiency) or by hypothalamic-pituitary pathologies determining a deficit of ACTH (secondary adrenal insufficiency). The clinical picture is determined by the glucocorticoid deficit, which may in some conditions be accompanied by a deficit of mineralcorticoids and adrenal androgens. The substitutive treatment is aimed at reducing the signs and symptoms of the disease as well as at preventing the development of an addisonian crisis, a clinical emergency characterized by hypovolemic shock. The oral substitutive treatment should attempt at mimicking the normal circadian profile of cortisol secretion, by using the lower possible doses able to guarantee an adequate quality of life to patients. The currently available hydrocortisone or cortisone acetate preparations do not allow an accurate reproduction of the physiological secretion pattern of cortisol. A novel dual-release formulation of hydrocortisone, recently approved by EMEA, represents an advancement in the optimization of the clinical management of patients with adrenal insufficiency. Future clinical trials of immunomodulation or immunoprevention will test the possibility to delay (or prevent) the autoimmune destruction of the adrenal gland in autoimmune Addison's disease.

Pharmacological preconditioning with erythropoietin attenuates the organ injury and dysfunction induced in a rat model of hemorrhagic shock

Pre-treatment with erythropoietin (EPO) has been demonstrated to exert tissue-protective effects against 'ischemia-reperfusion'-type injuries. This protection might be mediated by mobilization of bone marrow endothelial progenitor cells (EPCs), which are thought to secrete paracrine factors. These effects could be exploited to protect against tissue injury induced in cases where hemorrhage is foreseeable, for example, prior to major surgery. Here, we investigate the effects of EPO pre-treatment on the organ injury and dysfunction induced by hemorrhagic shock (HS). Recombinant human EPO (1000 IU/kg/day i.p.) was administered to rats for 3 days. Rats were subjected to HS on day 4 (pre-treatment protocol). Mean arterial pressure was reduced to 35 ± 5 mmHg for 90 minutes, followed by resuscitation with 20 ml/kg Ringer's lactate for 10 minutes and 50% of the shed blood for 50 minutes. Rats were sacrificed 4 hours after the onset of resuscitation. EPC (CD34(+)/flk-1(+) cell) mobilization was measured following the 3-day pre-treatment with EPO and was significantly increased compared with rats pre-treated with phosphate-buffered saline. EPO pre-treatment significantly attenuated organ injury and dysfunction (renal, hepatic and neuromuscular) caused by HS. In livers from rats subjected to HS, EPO enhanced the phosphorylation of Akt (activation), glycogen synthase kinase-3β (GSK-3β; inhibition) and endothelial nitric oxide synthase (eNOS; activation). In the liver, HS also caused an increase in nuclear translocation of p65 (activation of NF-κB), which was attenuated by EPO. This data suggests that repetitive dosing with EPO prior to injury might protect against the organ injury and dysfunction induced by HS, by a mechanism that might involve mobilization of CD34(+)/flk-1(+) cells, resulting in the activation of the Akt-eNOS survival pathway and inhibition of activation of GSK-3β and NF-κB.