Cost-Effectiveness of Extracorporeal Photopheresis in Patients With Chronic Graft-vs-Host Disease.

Background: The mainstay first-line therapy for chronic graft-vs-host disease (cGVHD) is corticosteroids; however, for steroid-refractory patients, there is a distinct lack of cost-effective or efficacious treatment. The aim of this study was to assess the cost-effectiveness of extracorporeal photopheresis (ECP) compared with standard-of-care therapies for the treatment of cGVHD in Australia. The study formed part of an application to the Australian Government to reimburse ECP for these patients. Methods: A cost-utility analysis was conducted comparing ECP to standard of care, which modeled the response to treatment and disease progression of cGVHD patients in Australia. Mycophenolate, tacrolimus, and cyclosporin comprised second-line standard of care based on a survey of Australian clinicians. Health states in the model included treatment response, disease progression, and death. Transition probabilities were obtained from Australian-specific registry data and randomized controlled evidence. Quality-of-life values were applied based on treatment response. The analysis considered costs of second-line treatment and disease management including immunosuppressants, hospitalizations and subsequent therapy. Disease-specific mortality was calculated for treatment response and progression. Results: Over a 10-year time horizon, ECP resulted in an average cost reduction of $23 999 and an incremental improvement of 1.10 quality-adjusted life-years per patient compared with standard of care. The sensitivity analysis demonstrated robustness over a range of plausible scenarios. Conclusion: This analysis demonstrates that ECP improves quality of life, minimizes the harms associated with immunosuppressant therapy, and is a highly cost-effective option for steroid-refractory cGVHD patients in Australia. Based in part on this analysis, ECP was listed on the Medicare Benefits Schedule for public reimbursement.

Androgens stimulate human vascular smooth muscle cell proteoglycan biosynthesis and increase lipoprotein binding.

Vascular smooth muscle cell (VSMC) proliferation and proteoglycan biosynthesis are two critical contributors to the development of atherosclerosis. We investigated the effects of specific androgens, androstenedione, dihydrotestosterone, and testosterone, on proteoglycan biosynthesis in human VSMC derived from internal mammary arteries. Vascular SMCs were metabolically labeled with [(35)S]sulfate or [(35)S]methionine/cysteine to assess glycosaminoglycans (GAGs) or proteoglycan core protein, respectively. The electrophoretic migration of radiolabeled proteoglycans was assessed by SDS-PAGE. Proteoglycan-low density lipoprotein (LDL) interactions were assessed using LDL affinity columns. Treatment of VSMCs with androstenedione (100 nm), dihydrotestosterone (10 nm), or testosterone (100 nm) increased [(35)S]sulfate incorporation into GAGs by 24.8% (P < 0.05), 22% (P < 0.05), and 32.5% (P < 0.05), respectively. Treatment of VSMCs with testosterone did not alter [(35)S]methionine/cysteine incorporation into proteoglycan core protein, suggesting that the effect of testosterone was associated with an increase in GAG length. Dihydrotestosterone (10 nm) and testosterone (100 nm) treatment of VSMCs resulted in the synthesis of biglycan and decorin that showed reduced electrophoretic mobility by SDS-PAGE, indicating an increase in GAG length. The effect of testosterone treatment on [(35)S]sulfate incorporation and GAG length was reversed by pretreatment of VSMCs with flutamide (1 mum), an androgen receptor antagonist. Proteoglycans from VSMCs treated with testosterone showed 11% (P < 0.01) higher binding capacity to LDL compared with proteoglycans from untreated cells. These results suggest a possible proatherogenic action of androgens through an elongation of GAG chains on proteoglycans in an androgen receptor-dependent manner.

Glucocorticoid responses to stress in castrate and testosterone-replaced rams.

Stress is an important contributor to cardiovascular disease and to reduced immunity and fertility. As the role of androgens in stress is uncertain, we investigated the effects of testosterone (T) on hormonal responses to stress in conscious Romney Marsh wethers. Six T-treated sheep and six control sheep were stressed by exposure to a psychological and a metabolic stimulus. Baseline glucose levels were significantly lower in the treated animals compared with controls (p=0.002). T treatment significantly attenuated ACTH (p<0.01) and cortisol (p<0.05) responses to metabolic stress. Following psychological stress, ACTH responses were significantly lower in treated sheep compared with controls (p<0.05), but differences in mean cortisol responses did not reach significance. There were no significant differences in epinephrine or norepinephrine responses following either stressor. We conclude that T replacement in wethers lowers glucose and attenuates responses to metabolic and psychological stress. While the implications of these results for human physiology require further studies, they suggest that male hypogonadism may play a role in determining the risk of cardiovascular disease and diabetes.

Dehydroepiandrosterone increases endothelial cell proliferation in vitro and improves endothelial function in vivo by mechanisms independent of androgen and estrogen receptors.

Dehydroepiandrosterone (DHEA) may be beneficial in cardiovascular health, but mechanisms of DHEA action in the cardiovascular system are unclear. We have therefore 1) determined DHEA effects on the proliferation of cultured endothelial cells (EC), 2) compared effects of DHEA with estradiol (E) and testosterone (T), and 3) examined DHEA effects on subcellular messengers. We have in addition examined effects of DHEA (100 mg/d, 3 months) in 36 healthy postmenopausal women on blood pressure, lipids, and endothelial function, assessed noninvasively in large vessels by flow-mediated dilation of the brachial artery during reactive hyperemia, and in small vessels by laser Doppler velocimetry with iontophoresis of acetylcholine. DHEA, E, and T all increased EC proliferation; the effect of E was abolished by the estrogen receptor antagonist ICI 182,780, and that of T was abolished by the androgen receptor antagonist flutamide; neither blocked the effect of DHEA. In vitro, DHEA increased EC expression of endothelial nitric oxide synthase and activity of extracellular signal-regulated kinase 1/2. In vivo, DHEA increased flow-mediated dilation and laser Doppler velocimetry and reduced total plasma cholesterol. Thus, DHEA increases EC proliferation in vitro by mechanism(s) independently of either androgen receptor or estrogen receptor and in vivo enhances large and small vessel EC function in postmenopausal women.

The isoflavone metabolite cis-tetrahydrodaidzein inhibits ERK-1 activation and proliferation in human vascular smooth muscle cells.

Phytoestrogens have recently been proposed as alternatives to estrogens for cardiovascular protection; however, the effect of their metabolites on vascular biology is unclear. We studied the effect of a red clover-derived isoflavone metabolite cis-tetrahydrodaidzein (cis-THD) on human vascular smooth muscle cell (VSMC) proliferation. Cis-THD significantly inhibited platelet-derived growth factor (PDGF) BB-induced DNA synthesis (10% at 1 nmol/L, 17% at 10, 100 nmol/L; 17beta-estradiol: 27% inhibition at 1, 10 nmol/L, 33% at 100 nmol/L). Cis-THD reduced PDGF BB-induced increase in cell numbers. Cis-THD showed high binding affinity to estrogen receptors (ER) by ER competitor assays; its inhibitory effect on DNA synthesis was abolished by the ER antagonist ICI 182780 (100 nmol/L), indicating ER-mediation. Immunoprecipitation assays revealed that cis-THD inhibited PDGF BB-stimulated activation of mitogen-activated protein (MAP) kinase ERK-1 by 34% at 1 nmol/L, 58% at 10 nmol/L, and 81% at 100 nmol/L, while MAP kinase JNK and p38 activities were unaltered. Thus, the isoflavone metabolite cis-THD inhibits PDGF-induced ERK-1 activation and cell proliferation in human VSMC, suggesting a potential beneficial effect in cardiovascular protection.

High glucose abolishes the antiproliferative effect of 17beta-estradiol in human vascular smooth muscle cells.

We examined effects of 17beta-estradiol (E(2)) on human vascular smooth muscle cell (VSMC) proliferation under normal (5 mmol/l) and high (25 mmol/l) glucose concentrations. Platelet-derived growth factor (PDGF) BB (20 ng/ml)-induced increases in DNA synthesis and proliferation were greater in high than normal glucose concentrations; the difference in DNA synthesis was abolished by a protein kinase C (PKC)-beta inhibitor, LY-379196 (30 nmol/l). Western blotting showed that PKC-beta(1) protein increased in cells exposed to high glucose, whereas PKC-alpha protein and total PKC activity remained unchanged, compared with normal glucose cultures. In normal glucose, E(2) (1-100 nmol/l) inhibited PDGF-induced DNA synthesis by 18-37% and cell proliferation by 16-22% in a concentration-dependent manner. The effects of E(2) were blocked by the estrogen receptor (ER) antagonist ICI-182780, indicating ER dependence. In high glucose, the inhibitory effect of E(2) on VSMC proliferation was abolished but was restored in the presence of the PKC-beta inhibitor LY-379196. Thus high glucose enhances human VSMC proliferation and attenuates the antiproliferative effect of E(2) in VSMC via activation of PKC-beta.

Testosterone (T) enhances apoptosis-related damage in human vascular endothelial cells.

Androgens may contribute to higher cardiovascular risk in men via deleterious effects on vascular endothelial cells (EC). We examined the effects of androgens on male human umbilical vein EC (EA.hy926) in culture. [(3)H]Thymidine incorporation assays showed that after 24-h serum deprivation, testosterone (T) (but not dehydroepiandrosterone nor 17beta-E2) induced significant dose-dependent decreases in DNA synthesis (10-16% at 1-100 nmol/liter); the AR antagonist flutamide (100 nmol/liter) abolished this effect of T. After 48-h serum deprivation, typical apoptotic DNA patterns were detected in agarose gels, and the number of floating cells indicative of severe damage was significantly greater after T treatment for 48 and 72 h (13.7 +/- 0.5% and 30.2 +/- 2.5%, respectively) than the control values (9.7 +/- 1.05% and 23.7 +/- 3.0%). Analysis of attached cells by annexin V-fluorescein isothiocyanate/propidium iodide staining showed that after 48-h serum deprivation, T significantly increased the number of cells in the early (16.0 +/- 1.1%) and late (8.3 +/- 0.3%) stages of apoptosis compared with control (6.8 +/- 1.0% and 4.0 +/- 0.2%, respectively); such increases in apoptosis-related damage were also observed, to a lesser degree, in serum-enriched culture. Western blotting showed that B cell leukemia/lymphoma-2 protein (Bcl-2) expression decreased significantly in serum-deprived EC treated with T. Thus, T reduces DNA synthesis and enhances apoptosis after serum deprivation in EC, possibly related to reduced Bcl-2 expression.

Dehydroepiandrosterone inhibits human vascular smooth muscle cell proliferation independent of ARs and ERs.

Dehyroepiandrosterone (DHEA), an adrenal-derived steroid, has been clinically implicated in protection against coronary artery disease and experimentally in inhibition of atherosclerosis and plaque progression. Because DHEA is enzymatically metabolized to androgens or estrogens, it is not clear whether DHEA exerts effects directly or after conversion to these hormones, both of which are associated with well-characterized pathways of action. We therefore examined the effects of DHEA on proliferation of human vascular smooth muscle cells (VSMCs) in culture in the presence or absence of the ER antagonist ICI 182,780 and the AR antagonist flutamide and compared them with the effects of 17beta-estradiol, androstenedione, and T. We also determined the affinity of DHEA for ERs and ARs in VSMC and its specific binding in intact cells. To explore a possible mechanism for DHEA action in these cells, we measured the phosphorylation of ERK-1, c-jun N-terminal protein kinase, and p38 (three members of the MAPK superfamily). Both DHEA and 17beta-estradiol significantly inhibited platelet derived growth factor (PDGF)-BB-induced increases in VSMC proliferation, whereas androstenedione and T increased proliferation. Although E2-induced inhibition of the PDGF effect was abolished by ICI 182,780 and T-induced stimulation was abolished by flutamide, neither receptor antagonist altered the inhibitory effect of DHEA. Binding studies confirmed the presence of both ERs and ARs; DHEA showed minimal affinity for either receptor but bound specifically and with high affinity to putative receptors in intact cells. Following 4-h incubation with DHEA (1-100 nM), ERK1 phosphorylation was significantly reduced in a dose-dependent manner, whereas neither c-jun N-terminal protein kinase nor p38 kinase activity was altered by either PDGF-BB or DHEA. DHEA inhibits human VSMC proliferation by a mechanism independent of either ARs or ERs, presumably via a DHEA-specific receptor that involves ERK1 signaling pathways.