Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Autoimmune diseases characterized by activation of immune effector cells and damage of target organs are currently treated with a combination of several disease-modifying antirheumatic drugs (DMARDs) that preserve different immunomodulatory mechanisms. Such a combination treatment strategy not only provides synergistic effects but also reduces side effects from individual drug. Tetrandrine (Tet), purified from a creeper Stephania tetrandra S Moore, is a bis-benzylisoquinoline alkaloid and has been used to treat patients with silicosis, autoimmune disorders, and hypertension in Mainland China for decades. The accumulated studies both in vitro and in vivo reveal that Tet preserves a wide variety of immunosuppressive effects. Importantly, the Tet-mediated immunosuppressive mechanisms are evidently different from some known DMARDs. The synergistic effects have also been demonstrated between Tet and other DMARDs like FK506 and cyclosporin. These results highlight Tet a very potential candidate to be considered as one of DMARDs in the treatment of autoimmune diseases, especially rheumatoid arthritis. This review summarizes evidence-based in vivo and in vitro studies on this potential Chinese immunosuppressive herb.
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PMID:Immunomodulatory effects and mechanisms of plant alkaloid tetrandrine in autoimmune diseases. 1246 46

Intravenous cyclosporine has proven to be an alternative to emergency colectomy in steroid-refractory ulcerative colitis, whereas the experience with FK506 is limited. In this report we compare intravenous to oral FK506 treatment in 38 patients with refractory ulcerative (n = 33) or indeterminate (n = 5) colitis. FK506 was started intravenously in the first group (n = 18) at a dose of 0.01 to 0.02 mg/kg up to 14 days, followed by 0.1 to 0.2 mg/kg orally, or was started orally at this dose in a second group (n = 20). Additional azathioprine/6-mercaptopurine was given and steroids were tapered in responding patients, followed by a dose reduction of FK506. Clinical disease activity and laboratory parameters were assessed to evaluate efficacy and safety. Primary objectives were the induction of remission (Truelove index of mild) and colectomy-free survival. Treatment lasted for a mean of 7.6 months, and the mean observation period was 16.2 months. Eighteen of 38 patients improved within 14 days, and a complete remission was achieved in 13 patients after 1 month. A colectomy within 1 month was performed in 3 of 38 patients. The overall colectomy rate was 34%. One-half of the patients with a minimum follow-up of 2 years required a colectomy. Intravenous and per oral administration were equally safe and effective. The most frequent adverse events included tremor, hyperglycemia, hypertension, and infection, but none were severe. Renal impairment was rare and subsided upon drug withdrawal. In conclusion. FK506 is effective in the treatment of refractory colitis with per oral dosing being equivalent to intravenous administration.
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PMID:Response of refractory colitis to intravenous or oral tacrolimus (FK506). 1627 9

The efficacy and safety of tacrolimus (FK506; Prograf) were determined in 28 adult kidney transplant patients (20 males and 8 females), aged 18-68 years (mean+/-S.D.: 46.9+/-4.03 years). Induction therapy was ATG-F (n=23), daclizumab (n=3), or none (n=2), and maintenance immunosuppression consisted of tacrolimus, combined with mycophenolate mofetil (MMF; n=26) or azathioprine (AZA; n=2) and prednisone (Pred). In seven patients, cyclosporine A microemulsion (Neoral) was replaced by tacrolimus for acute rejection (AR; three patients), slow graft function (SGF, two patients) and Neoral side effects (two patients). Acute rejection occurred in five patients (17.8%), three of whom were steroid-resistant treated with a second course of ATG-F. Infection occurred in 10 patients (35.7%) with a total of 15 infectious episodes, comprising bacterial (73%) and viral (27%) infections related to CMV. Other side effects related to tacrolimus were hypertension in four patients (14%) and post-transplantation hyperglycemia in nine patients (32%), three of whom required insulin therapy. In addition, hypercholesterolemia and hypertriglyceridemia occurred in six (21%) and eight patients (28.5%), respectively. The patient's hospital stay was 12.7+/-1.3 days (range: 8-24 days), and mean serum creatinine upon discharge, and at 1, 3 and 6 months following transplantation were: 2.1+/-0.5, 1.47+/-0.21, 1.41+/-0.53 and 1.23+/-0.11 mg/dl, respectively. The 6-month actuarial patient and graft survival rates were 100%. While tacrolimus is an effective calcineurin inhibitor for kidney transplantation (KT), severe acute rejection seen is related to highly sensitized patients, and the CMV infections noted were related to the presence of more CMV-negative recipients receiving kidneys from CMV-positive donors. Longer follow-up with a larger patient sample is needed to fully assess both the efficacy and safety of tacrolimus, including its metabolic effects.
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PMID:Single-center experience with tacrolimus-based immunosuppressive regimens in renal transplantation. 1283 78

It is estimated that there are greater than 100000 kidney transplant recipients with a functioning graft in the United States. Recent advances in immunosuppression have improved short-term graft survival rates and decreased early mortality by decreasing the incidence and therapy for acute rejection episodes. For those accepted on the waiting list, transplant prolongs patient survival compared with remaining on dialysis. During the 1990s, 3 new immunosuppressive drugs were introduced in clinical kidney transplantation. All were approved for use by the Food and Drug Administration after large, controlled, randomized trials. Mycophenolate mofetil (MMF), when combined with cyclosporine (CSA) and prednisone, lowered acute rejection rates by nearly 50% compared with control. Tacrolimus compared with CSA also significantly reduced acute rejection rates in kidney transplant recipients, but was associated with a significant increase in posttransplant diabetes mellitus (PTDM) in the early trials. When evaluated in combination with MMF, the incidence of PTDM was much lower. At the end of the decade, sirolimus was shown in several randomized trials to lower acute rejection rates and is believed to be less nephrotoxic compared with calcineurin inhibitors. All of the randomized trials were not statistically powered to assess long-term superiority. Registry analyses have been performed that appear to show some long-term benefit of immunosuppressive therapy with MMF. Other outcome assessments in kidney transplant recipients include risk factors for chronic allograft nephropathy, hypertension, hyperlipidemia, and bone disease. Although there are few randomized trials, understanding of the significance of these common complications has progressed and strategies for therapy and intervention have been developed. This article focuses on the randomized trials of immunosuppressive therapy and complications associated with use of these drugs. In addition, we review the current management and intervention for the comorbidities associated with the long-term clinical management of the kidney transplant recipient.
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PMID:Outcomes in kidney transplantation. 1283 99

Rejection is the leading cause of corneal graft failure, induced by loss of the so-called eye immune privilege. Prevention of graft rejection with immunosuppressive therapy is then necessary. Topical corticosteroids are currently the gold standard, and steroids are the only treatment for acute rejection episodes. Steroids are nonspecific immunosuppressive agents, and they can induce glaucoma, cataract, infections, and epithelial defects. Cyclosporin has a specific effect, because it inhibits interleukin-2 transcription and, consequently, the specific activation of T lymphocytes. When cyclosporin is given orally, it effectively prevents graft rejection in high-risk recipients, but it may induce severe side effects (i.e., systemic hypertension, kidney deficiency, and malignant tumor induction). When cyclosporin is given topically, it can effectively replace steroids in case of dexamethasone-induced glaucoma and graft infection, but it can also induce serious corneal epithelial defects. Cyclosporin is not a treatment for acute rejection episodes. Mycophenolate mofetil and FK 506 are promising drugs, but currently they cannot be used routinely to prevent corneal graft rejection.
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PMID:[Immunosuppression in corneal transplantation]. 1291 Feb 7

Tacrolimus (Tac), which blocks T- and B-cell proliferation by inhibiting calcineurin, was first used for immunosuppression following heart transplant (HT) in 1989. Two multicenter randomized trials have compared Tac to the oil-based cyclosporine (CsA) formulation (both combined with azathioprine and steroids) in HT patients. The two drugs displayed similar patient survival rates and incidences of rejection, nephrotoxicity, diabetes, and infections. The Tac group however, showed a lower incidence of arterial hypertension (and, in one study, of dyslipidemia). A pilot study of Tac in combination with mycophenolate mofetil (MMF) and steroids suggested that maintenance of serum mycophenolic acid levels at 2.5 to 4.5 microg/mL yields lower rejection rates without greater toxicity than previous regimens. Currently, a European multicenter randomized trial is comparing Tac with Neoral CsA, both used in combination with MMF, steroids, and induction antibodies. For patients undergoing primary immunosuppression with CsA, Tac has proved effective for rescue from steroid-resistant acute rejection. It also has tentatively been used without other drugs in selected patients. It is a valid alternative to CsA in current immunosuppressive regimens, because it does not cause gingival hyperplasia or hirsutism and, thus, may improve the quality of life and treatment compliance of female and pediatric patients. It may be preferable to CsA for patients with arterial hypertension or intractable dyslipidemia. Current and future studies will clarify the efficacy and safety of regimens combining Tac with MMF or rapamycin.
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PMID:Tacrolimus in heart transplantation. 1296 69

A number of studies have reported a lower atherogenic lipid profile in liver transplant recipients under tacrolimus (FK506) than in those under cyclosporine A (CyA) immunosuppression. This has mainly been attributed to the steroid-saving effect of FK506. However, the effects of converting CyA to FK506 monotherapy on lipid metabolism have not been specifically investigated. In 20 patients with stable graft function, immunosuppressive monotherapy was switched from CyA to FK506 because of CyA-related side-effects (hypertension, nephrotoxicity, hypercholesterolaemia). Serum lipid levels were measured before and 3, 6 and 12 months after conversion. In 5 patients, a modification of immunosuppression became necessary during the study period (4 were reconverted to CyA, 1 to glucocorticoids). In the remaining 15 patients on FK506 monotherapy, 12 months after conversion, a slight decrease in mean serum cholesterol, a slight increase in LDL, but a significant decrease in mean serum HDL were observed, resulting in a significant increase in Chol/HDL and LDL/HDL ratios. Conversion of immunosuppressive monotherapy from CyA to FK506 had no beneficial effect on the atherogenic lipid profile in this selected study population of long-term liver transplant survivors.
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PMID:Impact of changing immunosuppressive monotherapy from Cyclosporin A to Tacrolimus in long-term, stable liver transplant recipients. 1450 23

1. The observation that the immunosuppressants, cyclosporine A (CsA) and tacrolimus, have pressor effects, but sirolimus does not, has led to an hypothesis that generalised sympathoexcitation, resulting from inhibition of calcineurin by CsA and tacrolimus underlies their pressor effects, because sirolimus does not inhibit calcineurin. It is unknown if sirolimus has haemodynamic actions not accompanied by a pressor effect, and whether or not the pressor effects of CsA and tacrolimus are accompanied by similar haemodynamic changes. Therefore, the first aim of our studies was to investigate these possibilities in conscious, chronically-instrumented, male, Sprague-Dawley rats. 2. CsA (5.9 mg kg(-1) bolus i.v.) caused rapid-onset, prolonged hypertension, tachycardia and mesenteric vasoconstriction. There was a slower onset renal vasoconstriction, but no significant change in hindquarters vascular conductance; all the effects of CsA were significantly greater than those of vehicle. CsA given by infusion (over 30 min or 2 h) caused changes qualitatively similar to those above. Repeated administration of CsA over 4 days did not enhance its cardiovascular effects. 3. Pretreatment with the angiotensin (AT(1)) receptor antagonist, losartan, and the endothelin (ET(A) and ET(B)) receptor antagonist, SB 209670, reduced the pressor and mesenteric vasoconstrictor effects of CsA. Additional administration of the alpha-adrenoceptor antagonist, phentolamine, completely inhibited the cardiovascular effects of CsA. 4. Tacrolimus (450 microg kg(-1) bolus i.v.) caused similar peak pressor and tachycardic effects to CsA, but these were much slower in onset, and were maximal when there were no significant regional vasoconstrictions, indicating that the pressor effect was probably due to a rise in cardiac output. However, although propranolol reversed the tachycardic effect of tacrolimus, it did not influence the pressor response. 5. Sirolimus (450 microg kg(-1) bolus i.v.) had no tachycardic action, and only a modest, transient pressor effect, accompanied by equally brief reductions in renal, mesenteric, and hindquarters vascular conductances. 6. The differences between the regional haemodynamic profiles of equipressor doses of CsA and tacrolimus, and the finding that sirolimus has significant cardiovascular actions, indicate that generalised sympathoexcitation, resulting from calcineurin inhibition (with CsA and tacrolimus), is unlikely to be the sole explanation of their pressor effects.
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PMID:Regional haemodynamic effects of cyclosporine A, tacrolimus and sirolimus in conscious rats. 1474 7

This is a retrospective analysis of 16 children started on tacrolimus with various types of treatment-resistant nephrotic syndrome. There are 13 patients with focal glomerulosclerosis, 1 minimal change disease, and 2 IgA nephropathy with nephrosis. The mean age of the children was 11.4 years (range 3.5-18.1 years) with a mean age at diagnosis of 5.6 years (range 1.6-13.3 years). All patients initially received prednisone 2 mg/kg per day. Other therapies for 15 of 16 included cyclosporine (n=15), chlorambucil (n=5), mycophenolate mofetil (n=5), levamisole (n=3), i.v. methylprednisolone (n=3), and cyclophosphamide (n=2). The major indication for the initiation of tacrolimus included treatment resistance/dependence (n=15) and intolerable side effects from other therapies (n=1). The average time from the diagnosis to initiation of tacrolimus was 5.3 years (range 0.3-13.3 years, median 6 years). The initial dosage of tacrolimus utilized was 0.1 mg/kg per day divided into two doses. The mean follow-up period was 6.5 months (range 2.5-18 months). Thirteen patients (81%) went into a complete remission within an average of 2 months (range 0.5-5.5 months), with 3 patients relapsing while on treatment. Three patients did not respond. Of these, 2 had partial remissions (13%) and 1 failed to respond. Adverse events included anemia (n=1), seizure (n=1), worsening or new-onset hypertension (n=5), and sepsis (n=1). All patients remain on tacrolimus. Tacrolimus is an effective, well-tolerated medication for treatment-resistant forms of nephrotic syndrome in children, with a complete remission rate of 81% and a partial remission rate of 13% (totaling 94%).
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PMID:Tacrolimus therapy in pediatric patients with treatment-resistant nephrotic syndrome. 1693 33

Cardiac transplantation is the definitive treatment for eligible patients with end-stage cardiac failure. Techniques have evolved to reduce surgical mortality to under 5%. Immediate and subsequent long-term survival is more dependent on acute and chronic rejection and the complications of immunosuppressive therapy. Ten-year survival is greater than 50%.The success of transplantation over the last 20 years has been largely due to the advances in immunosuppression. The most notable and dramatic milestone was the introduction of cyclosporine in the early 1980s, which resulted in a significant improvement in allograft and patient survival. Cyclosporine is a peptide that inhibits the immune system by suppressing T-helper cell activation via inhibition of calcineurin, a critical intracellular enzyme. Tacrolimus has a similar (but not identical) mechanism of action, and was introduced in the 1990s. Drugs such as cyclosporine and tacrolimus, generically referred to as calcineurin inhibitors, have become the cornerstones of immunosuppressive protocols. As a group, calcineurin inhibitors have adverse effects, including neurotoxicity, hypertension, and nephrotoxicity, which complicate their use. Early renal insufficiency manifests as postoperative oliguria (<50 mL/h urine output) or rising serum creatinine levels. There are a variety of postulated causes for calcineurin inhibitor-associated early renal insufficiency including direct calcineurin inhibitor-mediated renal arteriolar vasoconstriction, increased levels of endothelin-1 (a potent vasoconstrictor), as well as decreased nitric oxide production and alterations in the kidney's ability to adjust to changes in serum tonicity. Once early renal insufficiency occurs, no single treatment has been shown to be effective. Approaches discussed in this paper include reduction in calcineurin inhibitor dosages, as well as various drugs to promote increased renal perfusion such as misoprostol and dopamine. In addition, the paper emphasizes the importance of ruling out other causes of renal insufficiency in the early postoperative period, including volume depletion, depressed cardiac output, and mechanical obstruction to urine flow. Given that there is no highly efficacious treatment for this syndrome, ways to avoid its occurrence are desirable. One paper is referenced that suggests that avoidance of rapid changes in tacrolimus level during the first three days of therapy is associated with a low occurrence of early renal insufficiency.
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PMID:Calcineurin inhibitor-associated early renal insufficiency in cardiac transplant recipients: risk factors and strategies for prevention and treatment. 1496 63


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