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Multi-organ protection and the kidney, from nephroprotection, cardioprotection, neuroprotection to multi-organ protection. neuroprotection to multi-organ protection de la asociación
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GH. GLUHOVSCHI , GH. BOZDOG , L PETRICA , A. SCHILLER , V. TRANDAFIRESCU , S. VELCIOV , C. GLUHOVSCHI , F. BOB
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NEFROLOGÍA. Vol. XXIV. Número 6. 2004 FORMACIÓN CONTINUADA Multi-organ protection and the kidney. From nephroprotection, cardioprotection, neuroprotection to multi-organ protection Gh. Gluhovschi, Gh. Bozdog, L. Petrica, A. Schiller, V. Trandafirescu, S. Velciov, C. Gluhovschi y F. Bob Dept. of Nephrology, University of Medicine and Pharmacy «Victor Babes», Timisoara Lately in the literature some protection measures have been discussed, which are targeted against different risk factors that determine functional disturbances and organic lesions of the main organs: heart, kidney and brain. As a consequence, the terms of cardioprotection, nephroprotection and neuroprotection have been adopted. The surprise of multicentric studies has been that despite the presence of some observations that prove the concomitant damage of the three organs, it has not been always approached as a whole. One or the other of the analyzed organs is mentioned only briefly. The Framingham study, for example, is focused on cardiovascular lesions, the cerebral ones are mentioned, but the kidney is not very privileged in this study. Although sometimes a complex treatment is applied, which consists of measures of nephroprotection, cardioprotection and neuroprotection, this treatment is not defined by a single term, as a treatment that approaches many organs and, as a consequence, its results are not followed up equally. The cardiologist will talk about cardioprotection, the neurologist about neuroprotection, while the nephrologist will talk about nephroprotection. When the nephrologist has been obliged to deal with heart injuries, which occur frequently in renal diseases, measures of cardioprotection in the renal patient have been mentioned, for example in chronic renal failure. On the other hand, lesions of different organs interconnect. Recibido: 12-IV-2004. En versión definitiva: 18-IX-2004. Aceptado: 27-IX-2004. Correspondencia: Prof. Dr. Gheorghe Gluhovschi Calea Aradului, 8, Ap. 16 1900 Timisoara (Romania) E-mail: ggluhovschi@yahoo.com - cbob@mail.dnttm.ro MULTIORGAN PROTECTION CARDIOPROTECTION NEPHROPROTECTION NEUROPROTECTION Fig. 1.--The concept of multiorganprotection with reference to kidney, heart, brain. Stepwise it has been observed that an organism with chronic disease can benefit from nephroprotection in case of renal injury, cardioprotection, when the heart is affected, and neuroprotection when we deal with neurological injuries. The most typical example is given by the diabetic patient, who suffers from nephropathy, which needs nephroprotection, ischaemic heart disease, which is approached through cardioprotection, as well as atherosclerotic cerebral lesions, which suggest the need for neuroprotection. Like the definition of multiple organ sufferance in pathology, which includes the pathology of an organism with multiple organ injuries, the problem of multi-organ protection has been raised. This latter term has originally been used in multi-organ failure, an acute injury of multiple organs that benefits from 519 G. GLUHOVSCHI y cols. a complex therapy, which has the objective of finding solutions to the numerous problems that occur in this disease. The term of multi-organ protection in these situations is beginning to be used. Although chronic diseases lead to multiple organ injury, they are not defined as multiple organ sufferance, and the protection measures are approaching every organ as a part, such as: nephroprotection, cardioprotection, neuroprotection. The objective of this article is to analyze the prerequisites for defining multi-organ protection, and the advantages that derive from here. The three organs: kidney, brain and heart can be affected concomitantly under many circumstances. The kidney, heart and brain have a rich vascularization. The injury of the cardiovascular system can be produced by common pathological processes in the course of hypertension, vasculitis, as well as by vascular risk factors, which through the lesions they produce, have direct effects against the cardiovascular system. The kidney, heart and brain have a rich blood supply. High blood pressure afflicts the kidney, heart and brain concomitantly causing vascular lesions with resultant pathological and functional consequences. Patients with essential hypertension could also show plurivascular arterial lesions (cardiac, renal and cerebral) due to atherosclerotic processes. Lipid metabolism disturbances that are involved in atherogenesis are common to the vessel compartment of the three organs. Carbohydrate metabolism disturbances are common to all three organs during the course of diabetes. Other metabolic disturbances, disorders of acidbase balance, as well as oxidative stress can affect the three organs, as well as the body as a whole. Sometimes the simultaneous deposition of some pathological components can afflict many organs, including the kidney and the heart, as can be seen in amyloidosis. The hypoxia that accompanies anaemia can affect the brain and the heart simultaneously with direct consequences on their function. Increased salt intake is involved in blood pressure control bearing on the vessel compartment as a whole, as do hyperhomocysteinaemia, coagulation abnormalities and smoking. Chronic inflammatory processes are encountered in many disorders. They consist of the release of various cytokines and inflammatory proteins whose actions will influence the target organs. Sometimes the inflammatory process in one of the three organs leads to the response of the entire body, as is the case with the kidney during renal failure. Uraemia is considered a microinflammatory state. Zimmermann y cols. consider that inflammation en520 hances cardiovascular risk and mortality in haemodialysis patients2. The protective measures which attempt to address these abnormalities will be common to the kidney, heart, and brain, thus producing multi-organ protection. They include: ­ blood pressure control, ACE inhibitors playing a major role, ­ lipid metabolism corrections, ­ carbohydrate metabolism control, ­ reduced salt intake, ­ smoking cessation, ­ low-dose aspirin. Besides the above-mentioned factors, the three organs will be subjected to other potential risk factors, which will also need to be addressed during multiorgan protection: metabolic disturbances, anaemia and oxidative stress etc. Apart from these common measures responsible for multi-organ protection, other specific therapies will be aimed at depending on the circumstances. They concern the kidney, heart and brain during nephro-, cardio- and neuroprotection. In a patient with heart disease, arrhythmias will determine the necessity for specific therapy in addition to the common multi-organ protective measures. The correction of rhythm abnormalities will improve cardiac activity and, consequently, blood flow in the circulation. Proteinuria control is part of the nephroprotective measures. It diminishes hypoproteinaemia and directly contributes to correction of lipid profile abnormalities, which occur during the nephrotic syndrome. Thus, it will exert a beneficial effect on the blood vessels, with main implications for the kidney, heart and brain. It seems that some organ-specific measures will thus influence other organs as well. Other measures, which target the nervous system selectively, such as treatment of degenerative nervous disease, have limited effect on other systems. Multi-organ protection should comprise measures that address the three organs simultaneously, as well as those specific to one organ, as each body part can suffer from 2 insults, one specific to it, and one common to the other two. Very often the preponderant involvement of an organ requires the adaptation of the protection measures. Factors that pertain to the kidney are as follows: ­ proteinuria; ­ insufficient eritropoetin secretion- an important contributor to anaemia, with consequences for other organs; MULTI-ORGAN PROTECTION AND THE KIDNEY ­ retention of nitrogen products with secondary inflammation and toxic effects; ­ phosphorous and calcium metabolism disorders; parathormone is a putative uraemic toxin; ­ disturbances of the intrarenal circulation. Factors specific to the heart: ­ arrhythmias - atrial fibrillation can reduce cardiac output by 20%; ­ myocarditis. Factors specific to the brain, exerting an effect through the following: ­ neurotransmitters; ­ glutamate flow; ­ neurotrophic growth factors: FGFb, GDNF, VEGF. Organ protection measures will address all factors which retard the progression of the disease. Protection measures that act on the cellular level define cytoprotection. As an example erythropoetin has a cytoprotective effect on the central nervous system, as well as on the kidney 3. Other protection measures act at the molecular level. Some of them address the organ level, belonging to organ protection, while most of them affect many organs, belonging to multiorgan protection. Multi-organ protection and organ protection can be acute or chronic. As an example, multi-organ system failure requires rapid and extensive multi-organ protection. A single organ affection can also require acute protection. Acute cardioprotection is applied in acute coronary syndromes, during cardiac surgery and cardiac arrest. Acute renal failure prompts the need for acute nephroprotection. Its etiology could extend therapy from acute nephroprotection to acute multi-organ protection. Multi-organ protection could similarly be applied to chronic disorders of the kidney, heart, brain. We will remark that organ protection utilizes common measures with other organs, that which define Factors which affect many organs and systems, and which impose multi-organ protection measures Lesions of the cardiovascular systems: · Hypertension (anti-hypertensive drugs) · Vasculitis (corticotherapy, immunosuppression) · Endothelial lesions (sulodexide) Disorders of the lipid metabolism (diet, lipid-lowering drugs) Disorders of the carbohydrate metabolism Increased salt intake Hypoxia- anaemia (erythropoetin, iron, folic acid) Oxidative stress Smoking (smoking cessation) Hyperhomocysteinaemia Coagulation disorders (low dose aspirin) Uraemia -microinflammatory state (renal replacement therapies) Factors which act on target organs Brain specific factors Excerting effects through: · Neurotransmitters · Glutamate flow · Growth factors FGFb, GDNF, VEGF Factors specific to the heart Arrhythmias (antiarrhythmic drugs) Myocarditis (anti-inflammatory drugs) Factors that pertain to the kidney Proteinuria (NSAIDs, corticotherapy) Insufficient erythropoetin secretion (erythropoetin) Retention of nitrogen products, uraemic toxins (secondary inflammation, toxic effects) ­ renal replacement therapies Phosphorus and calcium (diet, inhibition of phosphorus absorbtion ­ calcium carbonate, sevelamer, calcimimetics) Disorders of intrarenal circulation (cessation of ACEIs and ARBs administration) Fig. 2. 521 G. GLUHOVSCHI y cols. Table I. Classification of organ protection Multi-organ protection: acute chronic (Nephroprotection + Cardioprotection + Neuroprotection) Main organ protection Nephroprotection: acute chronic Cardioprotection: acute chronic Neuroprotection: acute chronic multi-organ protection. At the same time there are measures that address only to the protection of one organ. In order to delineate multi-organ protection, we will briefly analyze nephro-, cardio, and neuroprotection, outlining the common, as well as the specific factors of progression. NEUROPROTECTION FROM THE STANDPOINT OF MULTI-ORGAN PROTECTION According to the Jain Biotech Report, an agent could be considered neuroprotective, if it prevents Cytoprotection Organ protection at the molecular levels Table II. Measures that combine those addressed to the nervous system with those addressed to other tissues Drug Anti-hypertensive drugs Perindopril Action Correct cerebral blood supply A net amelioration of distensibility and compliance of the carotid arteries Lowering of systolic blood pressure Cerebroprotective effect London y cols.,6 Authors Observations Regulate the circulation in different organs including brain, heart and kidneys In hypertensive and renal failure patients treated with perindipril Perindopril Progress study In essential hypertension and in normotensive subjects with high risk of stroke (reduce with 20% the risk of stroke) Protective effect increases the compliance of coronary vessels Metanalysis- studying the literature between 1996-2001, 38 trials, 83,161 patients, mean follow-up 4.7 years Reduction of incidence of coronary heart disease Trandolapril Quinalapril Lipid-lowering therapy (statins, non-statin drugs, diet) Protective effect on stroke in spontaneously hypertensive rats Relative risk reduction of stroke by lipid-lowering therapy by 17% Decrease in the effect of cholesterol Effect on the progression and stability of the plaque in intracranial atherosclerosis Cytoprotective and antiapoptotic effect Act at the cellular level Richer y cols.7 Vacher y cols. 8 Corvol y cols. 9 Crouse y cols. 10 Erythropoetin Drugs that block free radicals NO synthesis activation membrane stabilizers medication that blocks cellular adhesion ­ drugs that block proteic destructions ­ decrease in Na and K flux ­ anti-inflammatory drugs, especially COX2 inhibitors Neurotrophic factors Gene therapy Inhibition of apoptosis Measures targeted against endogenous and exogenous toxic effects Calcium channel blockers (nimodipin) Calcium channel modulators (flunarisine) Calcium channel chelators ­ ­ ­ ­ ­ Vesey y cols.11 Isenman and Schultz5 Digicayloglu y cols.12 In experimental brain injury and cisplatin induced nephrotoxicity Neurotrophic action Action at the gene level Neuroprotective action Their toxic effects act not only against the nervous system but also against other organs Neuroprotective effect Jain Pharma Biotech report4 Robertson y cols.13 Uraemic toxins -typical example Isenman and Schultz5 522 MULTI-ORGAN PROTECTION AND THE KIDNEY neuronal death by the interference of any one of the following processes: lesion of the central nervous system, ischaemia of an artery or hypoxia of any cause, including the protection against neurodegeneration and neurotoxins 4. Neuroprotection is targeted to: ­ ­ ­ ­ cerebral blood supply; traumatic injuries of brain and spinal cord; neurodegeneration endogenous and exogenous metabolic toxic effects (neurotoxins). Other neuroprotection measures mentioned by Isenman and Schultz, affecting processes which take place in cerebral tissues, are: a) measures which combine with processes in the nervous system and in other tissues, and which belong to multi-organ protection; b) protection measures specific to the nervous system, belonging to neuroprotection. b) Neuroprotection has a component that addresses strictly the nervous system, in neurodegenerative processes. The main diseases with neurodegenerative components are multiple sclerosis, amyotrophic lateral sclerosis, Alzheimer disease. These diseases will benefit from specific neuroprotection measures. An important role is played by multiglial activity control 15. To sum up there are: ­ Neuroprotection measures with an effect on other organs too, and which belong to multiorgan protection. ­ Specific neuroprotection measures which act on the nervous system. If protection measures targeted against cardiovascular diseases have proved their efficacy in cerebral lesions as well, clinical trials in neuroprotection could not demonstrate a positive effect in neurodegenerative conditions including surgery, epilepsy, traumatic brain and spinal cord injury, Alzheimer disease, Parkinson's disease, amyotrophic lateral sclerosis and some psychiatric diseases 16. THE ROLE PLAYED BY NEPHROPROTECTION IN MULTI-ORGAN PROTECTION Nephroprotection is composed of measures which block the progressive evolution of renal diseases. Acute neuroprotection is directed towards acute cerebral vascular events, including stroke. Neuroprotection could be applied to chronic vascular lesions, attributable to diffuse cerebral atherosclerosis or atheromatous plaques, located in different territories, more often in the carotid arteries. These measures are part of chronic neuroprotection. Ischaemic vascular lesions can lead to thrombosis. Embolic lesions of cardiac origin are sometimes present. Neuroprotection will address factors specific to the cerebral blood supply, and also measures common to other circulatory territories, such as coronary arteries and renal vessels. An important role is attributed to blood pressurelowering therapy. Hypertension leads to cerebral lesions through vessel rupture during acute events or through chronic injuries. The concomitant use of therapies addressed to vascular processes related to hypertension, such as lipidlowering agents and smoking cessation, is included in general multi-organ protection measures. According to Isenman and Schultz, an important neuroprotective role is exerted by the effect on cerebral blood vessels by some calcium channel acting agents: calcium channel blockers (nimodipin), calcium channel modulators (flunarisine) and calcium channel chelators 5. Table III. Specific neuroprotection measures Drug Specific GABA receptor antagonists Serotonin antagonists Opioid antagonists Growth factors FGFbeta and GDNF Vascular endothelial factor (VEGF) Action Decrease the glutamate flux which refers to neurotransmiters Authors Isenman and Schultz5 Compensate the lack of neurotrophins Promotes neurogenesis and cerebral angiogenesis. Therapeutical potential in ischaemic disorders Isenman and Schultz5 Sun y cols.14 523 G. GLUHOVSCHI y cols. Therefore the knowledge of progression mechanisms of renal diseases and the evaluation of the main therapies is necessary. These are presented in the article «Renoprotection: one or many therapies», published in Kidney Int 2001, 59 p: 1211-1226 by Hebert et al. In the following we will briefly present the measures shown in the afore mentioned paper, by maintaining the large frame of multi-organ protection- renal, cardiac and neural, respectively 17. As mentioned before, nephroprotection measures are targeted against progression mechanisms of renal diseases. Some of these mechanisms act not only against the kidney, but also in other systems, such as the vascular one. This complex protection is included in the multi-organ protection. Table IV presents the main mechanisms of the progression of renal diseases, which need measures of nephroprotection. Progression mechanisms of chronic kidney diseases require cellular and molecular mediators. They follow a common pathway, a fact which needs treatment strategies addressed to it, in order to stop the evolution of the disease. The most commonly utilized treatments are: ACEls, NSAIDs, mycophenolate mofetil 44, 45. Fishbane y cols. have demonstrated the cytoprotective effect of darbepoetin/ epoetin alfa using pig tubular and mouse mesangial cell cultures 3. CARDIOPROTECTION AND ITS RELATION TO NEPHROPROTECTION AND NEUROPROTECTION The heart is subjected to a large number of aggressions with the participation of multiple risk factors. Protection against them is referred to as cardioprotection. It may refer to acute events, being referred to as acute cardioprotection, or to chronic diseases, a fact which defines chronic cardioprotection. We shall first have a look at chronic cardioprotection, as it addresses through the measures taken, other organs too, such as the kidney and the brain. They are also nephroprotection and cardioprotection measures. This is due to some common factors acting upon the three organs, which implies taking common protective measures. The measures of acute cardioprotection are much more specific to the heart, the other organs, such as kidney and the brain, benefiting indirectly from the cardiac protective effect. According to Kannel, based on the Framingham study, the most important risk factors in coronary disease are: 524 ­ Hypertension, dislipidaemia by increase of LDL cholesterol and a low level of HDL cholesterol, smoking, diabetes, advanced age. Other high risk factors for cardiovascular disease are represented by: physical inactivity, obesity, premature cardiac disease, family history, hypertrigliceridaemia, lipidic profile including low and dense LDL, increase in homocysteine level, abnormal coagulation factors 46. ­ The metabolic syndrome is a high risk factor for heart disease, irrespective of the cholesterol leve 47, 48. Other risk factors for the development of coronary disease are represented by left ventricular hypertrophy on electrocardiography 49. According to Wilson, emerging risk factors for chronic heart disease are: C reactive protein, microalbuminuria, vitamins and homocysteine, plasma fibrinogen, and coronary artery calcification 49. The main affection related to the cardiovascular apparatus is represented by atherosclerosis, a diffuse process which affects the heart, the kidneys, the brain and the limbs. The presence of an atherosclerotic lesion in an area raises the suspicion of its existence in other vascular areas, too. Thus, the Framingham study has revealed the fact that those who had an initial myocardial attack had history of stroke in 5-10% of the cases. Analyzing the risk factors involved in cardiac lesions, we see that they are mostly risk factors for the entire cardiovascular system, being able to produce lesions in other organs too, such as the brain, the kidneys, and the limbs. Therefore, the cardioprotection factors addressing the heart are, to a certain extent, common to the other organs such as the kidney, the brain, and to the entire vascular system. Ranking first is hypotensive medication, primarily ACEIs or ATII receptor blockers, followed by lipid lowering medication, correction of carbohydrate metabolism disturbances, cessation of smoking, etc. Cardioprotection means not only prevention of lesions to coronary vessels, but it is also prevention of myocyte affection. The myocardium subjected to chronic activity undergoes processes of reshaping, a phenomenon referred to as myocardial remodelling. It includes myocitary hypertrophy, contractile dysfunction, myocyte apoptosis and matrix remodelling. If the process is not stopped, the lesions will evolve towards myocardial failure 50. Left ventricular hypertrophy is mainly under the influence of angiotensin11 which acts as a vasoconstrictor as well as a growth factor promoter: ACEls MULTI-ORGAN PROTECTION AND THE KIDNEY Table IV. Mechanisms of renal diseases and measures of nephroprotection Factors Mode of action Consequences Affected org. K HB Protection measures Studies AH c mpact on SpeT ific GABA receptor Iantagonistsrenal Decrea­eIncrese in albuminu- + refers toBneurotransmiters s the glutamate flux which + + P lowering ria (proteinuria) medication Serotonin antagonists circulation Increase of filtration ­ Benign or malignant Opioid antagonists pressure nephrosclerosis Taal MV y and Schultz5 Isenman cols. 18 Brenner BM19, Remuzzi G and Bertani T20 Growth factors FGFbeta and GDNF Compensate the lack of neurotrophins Isenman and Schultz5 AII Excess ­ Direct action on Influences the vascular + + + ACEIs Taal y cols.18, mesangial cells and system directly and ARBs Brenner 19, Kuczera y Vascular endothelial factor (VEGF) Promotes neurogenesis and cerebral angiogenesis. Therapeutical Sun y cols.14 tubules also through ACEIs + ARBs cols. 21, Taylor AA22 potentialdinstischaemic disorders al o erone ­ Direct action on vessels or through Local activation of ACEIs + ARBs (interfere RAS RAS with the local RAS) Aldosterone excess Aldosterone-independent mediator of renal remodelling + ­ Myocardial fibrosis ­ Renal fibrosis ­ Progression of hypertensive renal vascular disease and diabetic nephropathy + AHT + Associated to NaCl excess influences BP + + + Anti-aldosterone drugs +/RAS blockage through ACEIs Brown y cols.23 Hollenberg y cols.24 Excess of NaCl Takes part in pathogenic mechanisms of hypertension Increased urinary volume determines an accelerated renal disease progression through increase of intratubular pressure Contribute to atherosclerosis + Diuretics Natrium restriction + Appropriate water intake control Heeg y cols.25, Bakris and Smith26 Hebert y cols.17, Ozkaya y cols.27 Water overload Lipid metabolism disorders + Primary vascular lesions on renal, coronary and cerebral circulation + Atherosclerosis High risk of progressive renal function loss Cardiovascular morbidity and mortality + + Diet, Lipid lowering drugs: statins and fibrates with antiproteinuric effect + RAS blockers Statins Selective NSAIDs Sulodexide Wanner C and Quaschning T28, Vogt29, Kasiske y cols.30 Hebert17, Vogt29, Gluhovschi y cols.60, Gambaro y cols.59 Proteinuria ­ Hypoproteinaemia ­ Increased serum lipid production with secondary dislipidaemia ­ Overload of proximal tubular epithelial cells with complement, inflammaroty lipoproteins, iron species + Anaemia Leads to progression of renal disease + + + Iron, folic acid, eryth- Bagnis y cols.31, Fine y ropoietin (reduces left cols.32, Bahlmann y ventricular mass, ame- cols.33 liorates cardiac ischaemia, improves outcomes in CRF) Alfa-beta blockers (carvedilol) improved the efferent sympathetic nerve traffic survival and ejection fraction in dialysis patients with congestive heart failure Dikow y cols.34, Cice y cols.35, Converse y cols.36 Sympathetic overactivity Renal damagechemo- and baroreceptors are activated + Increase in cathecolamine turnover in hypothalamus and increase in efferent sympathetic nerve traffic + 525 G. GLUHOVSCHI y cols. Table IV. Mechanisms of renal diseases and measures of nephroprotection (cont.) Factors Mode of action Consequences Affected org. K HB Protection measures Studies Hypergl caem receptor Metabolic disorders ecreaDisthebance of matrix which refers toCneurotransmiters + + + orrection of Specific uGABAia in antagonists D se tur glutamate flux di rbet ni antagonists lead to lesions of due to protein hyperglycaemia Seaotoesnmellitus kidney heart and brain glycosilation Correction of Opioid antagonists Lipid metabolism will Microangiopathy associated metabolic disorders Growth factors FGFbeta particGDNF atheros- peMaceothe ilackthy neurotrophins and ipate in Com nsat r ang opa of clerosis which affects Fibrosis and sclerosis blood vessels glomerulosclerosis Vascular endothelial factor (VEGF) Promotes neurogenesis and cerebral angiogenesis. Therapeutical pa a in ischaemic disorders+ + Phosphorus and HyperphosphataemiotentiClalcium deposits in Diet, phosphorus and Calcium balance disorders with secondary hyperparathyroidism Increased levels of parathormone which is considered uraemic toxin Vascular risk factor vessels Parathormone leads to cardiac fibroblasts activation calcium balance disorders correction: vitamin D, sevelamer, low protein diet Parving y cols.37Schultz5 Isenman and Isenman and Schultz5 Sun y cols.14 Aman y cols.38 Smoking + In diabetic nephropathy, IgA nephropathy, Polycystic kidney- is an independent risk factor + + + Orth y cols.39 Plasma homocyteine + Folic acid Samuelson y cols.40 Benett-Richards y cols.41 Hebert y cols.17 Increase of procoagulants Vascular risk factor + + In overweight patients focal segmental glomerulosclerosis + + + + + + Weight loss Decrease of oestrogens Vascular risk factor Insulin resistance Cardiovascular risk factor Increase of C peptide Increase of plasmatic insulin Hebert y cols.17 Hypokalaemia Renal lesions: progres- + sive renal fibrosis Negative effect on heart: arrhythmias Can produce glomeru- + Utilized in order to reduce proteinuria in lar and interstitial renal diseases, have lesions an effect on the prostaglandin system + Administration of potassium NSAIDs + Cessation of treatment Cramer and Bock42, Mukherjef y cols.43 can inhibit the All action and slow the progression of vascular and myocardial remodelling. A cardioprotective measure is performed through this. The hypertrophy process is also under the influence of other factors, such as cathecolamines, neurohormones, endothelin, aldosterone, TNF alpha, specific oxygen species. These factors, in their turn, require cardioprotective measures. Besides activation of the renin- angiotensin- aldosterone system, neurohormonal stimulation is also 526 achieved by the activation of the sympathetic nervous system. The activation of the sympathetic nervous system determines functional and structural changes which will influence the cardiovascular disease. Complex studies have demonstrated that betablockers significantly lower morbidity and the death rate of patients with cardiovascular diseases. Beta-blockers and statins have additive anti-atherosclerotic effect, acting in various ways. Also, RAS blockade associated with statins has the same effect 29. MULTI-ORGAN PROTECTION AND THE KIDNEY The Heart Protection Study conducted on 20,000 persons with cardiovascular event risk has revealed, in a group of persons, that after 5 years simvastatin reduced heart attacks, the first stroke and the need for revascularization by 24% 51. In patients having undergone beta-blockers and statins therapy simultaneously, it has been shown that the favourable effect of these associations is more significant. Coronary heart protection needs therapeutic measures addressing hypertension, lipid metabolism disturbances, arterial thrombosis, arrhythmias etc. Schwartzkopf y cols. underline in essential AHT patients the regression of left ventricle hypertrophy and of myocardial fibrosis, the latter being attributed to the direct and long-term effects of perindopril upon the collagen metabolism at myocardial level 52. Endothelial injury in situations that affect the cardiovascular system determine important changes Endothelial injuries are produced during the affection of the cardiovascular system, due to numerous factors, such as AHT, angiotensin II, endothelin, lipids, smoking, increase of procoagulants etc. H von Bayer y cols. mention the Virchow triad, that contains the following: arterial wall anomalies, blood components changes and haemodynamic alterations 53. These phenomena are associated with micro inflammatory processes, especially in the atheromatous plaque. Endothelin receptors and AT I receptors participate in this process as well 54, 55. Endothelial dysfunction with NO and CGMP deficiency play an important role in the pathogenesis of essential AHT and of AHT secondary to CRF, even in the first stages 56. CRF is regarded as a vasculopathic state 57. Microalbuminuria can occur, according to Schiffrin, in parallel with the development of endothelial dysfunction, as hypertension progresses 58. Among drugs which act on glycosaminoglycans, with a role in reduction of their alteration, Sulodexide has been evidenced, its role being proved in the decline of proteinuria in diabetic nephropathy59, but also other nephropathies 60, thus developing a nephroprotective activity. Acute cardioprotection relates primarily to myocardic acute ischaemia, cardiac surgery, and cardiac arrest. A metabolic and pharmacological endogene cardioprotection; is described within endogene cardioprotection, the main role is played by the stimula- tion of the adenosinic receptor which activates C phospholipase with endogene protector release, favouring nitric oxid synthesis. Metabolic cardioprotection is based on insulin and glucose infusion. Pharmacological cardioprotection benefits from beta-blockers, calcium channel blockers, angiotensin- conversion enzyme inhibitors, trimetazidine as cellular anti-ischaemic agenel. Acute cardioprotection measures can also act during acute multi-organ suffering, the kidney obviously benefiting from such measures. Thus, acute cardioprotection measures can also have nephroprotective effect. For example, their application in acute myocardial infarction, ensuring an adequate blood pressure for renal perfusion, can prevent the onset of renal ischaernic lesions and of ARF At the same time, in a patient with ischaemic atherosclerotic lesions, including cerebral ones, they can prevent a cerebral vascular event. Cardioprotection and chronic renal diseases Patients with chronic kidney diseases with cardiovascular involvement benefit from cardioprotective measures as well. The chance of a patient with CKD to develop ,end stage renal failure is lower then the chance to die from a cardiovascular complication62. Data from the Hypertension Detection and Follow-up Program (HDFP) involving nearly 11,000 individuals show that 58 percent of deaths in participants with baseline serum creatinine greater than or equal to 1.7 mg/dL were secondary to cardiovascular causes 63. As the great majority of renal diseases show the affection of cardiovascular system especially in the renal insufficiency stage, cardioprotection measures are necessary, as well as nephroprotection measures. Partly these measures overlap. Many of the risk factors for kidney disease and cardiovascular disease are similar 64. Dikov has analysed the cardiovascular risk factors in renal failure and found that there are not only classical risk factors: hypertension, hypervolaemia, dislipidaemia, sympathetic hyperreactivity, hyperhomocysteinaemia, but also nonclassical risk factors such as anaemia, hyperphosphataemia, hyperparathyroidism and microinflammation. Most of the risk factors superpose on the cardiovascular ones, cardioprotection measures being similar to those utilized in nephroprotection 34. London y cols. have demonstrated by treatment with perindopril administered to a group of CRF patients of various etiologies, an improvement of diastolic performance of the left ventricle concomitantly with a significant reduction of the left ventricle and 527 G. GLUHOVSCHI y cols. decrease in septal hypertrophy. These results have been obtained independently of the AHT control6 London attributes the above- mentioned results to the blocking of the circulating angiotensin renin system and to that of the local or cardiac one, respectively. The blocking of the local system would prevent the action of ATII from stimulating myocytary hypertrophy at myocardial level and that of aldosterone from initiating myocardial fibrosis6 . Blockers, thrombolysis, aspirin and statins can be considered as cardioprotective drugs 65. Anaemia is a factor implied in cardiac hypertrophy, frequently encountered in uraemic patients 66. Rabelink considers that cardiovascular mortality in patients with end stage renal failure is probably among the highest in medicine 67. The atherosclerosis begins in early stages of chronic renal disease and worsens in haemodialysis patients 68. According to Jungers y cols. cardioprotection is an essential component of the treatment of chronic renal failure in the predialytic stage 69. The prevention of left ventricular hypertension by an appropriate control of BP by utilizing ACEls, anaemia control and volaemic control, reduce the risk for cardiovascular disease before and after renal transplantation 68. Chronic inflammation as evidenced by increased levels of Creactive protein (CRP), predicts all causes of cardiovascular mortality in short-term studies70. Locatelli y cols. showed that cardiovascular diseases have a main role in the morbidity and mortality of patients with renal replacement therapy- 50% of the causes of death 66. Cardioprotection has more recently emerged as another fundamental goal in the treatment of CRF patients in the predialysis phase 71. It should be performed in patients with renal replacement therapies as well. Cardioprotection and cerebral diseases Many studies are targeted against concomitant cardiac and cerebral lesions with common protection measures. The Prospective Randomized Evaluation of the Vascular Effects of Norvasc Trial has evaluated the protective role of Norvasc in the progression of coronary and carotid lesions 72. Losartan International for End Point Reduction in Hypertension Study (LIFE) reports a substantial decrease of cardiac events and stroke in patients treated with losartan 73. Mannami y cols. presented in the Suita Study (a populational study performed on 1,896 males and 2,102 females) a strong and significant relationship 528 between aggregation of major coronary risk factors and the acceleration of carotid atherosclerosis in the general population of a Japonese City74. The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack (ALLHAT) performed on 33,357 participants has highlighted the role of chronic heart disease, stroke, angina treated in out-patients, cardiac failure and peripheric vascular disease75. Sever y cols., reported in a randomized multicentric study the prevention of coronary and stroke events with atorvastatin in hypertensive patients who have average or lower than average cholesterol concentrations in the Anglo-Scandinavian Cardiac Outcomes Trial (Lipid Lowering Arm ASCOTLLA) 76. It can be seen that the cardioprotection measures addressing the vascular system in general, ensure, besides the protection of the heart (cardioprotection), that one of the kidney (nephroprotection) and of the nervous system (neuroprotection), practically achieving multi-organ protection measures. SOME DATA CONCERNING THE CONCOMITANT RENAL, CARDIAC AND CEREBRAL INJURY As we mentioned earlier in a brief presentation of nephroprotection, neuroprotection and cardioprotection, the fact that the affection of one organ in general is not an isolated phenomenon, but it also is associated with the affection of other organs and systems as well. We want to re-discuss the main factors through which the kidney intervenes in the production of cardiac and cerebral lesions. Renal affection often determines the subsequent onset of cardiac and of neurological involvement. In patients with normal renal function cardiac and cerebral lesions are due to vascular injuries of the heart and the brain, lesions that follow hypertension and/or metabolic disturbances. A great majority of patients with glomerular disease show hypertension, often severe and associated with cardiac and/or cerebral lesions. Renal vascular lesions could reach obstruction of over 75% with an aggravation of initial hypertension, due to renal artery stenosis, which can lead to cerebral and cardiac lesions, as well as renal lesions on the non-stenosed kidney benign or malignant nephroangiosclerosis. Lipid metabolism disturbances and coagulation disorders that occur in the nephrotic syndrome could lead to atherosclerotic lesions, to vessel injuries, such as coronary and cerebral ones. Renal vascular thrombosis is not an exception. At the same time patients with renal failure show lipid metabolism disturbances, which together with
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