Alessandra Crisafulli

Effects of Genistein and Hormone-Replacement Therapy on Bone Loss in Early Postmenopausal Women: A Randomized Double-Blind Placebo-Controlled Study

The natural isoflavone phytoestrogen genistein has been shown to stimulate osteoblastic bone formation, inhibit osteoclastic bone resorption, and prevent bone loss in ovariectomized rats. However, no controlled clinical trial has been performed so far to evaluate the effects of the phytoestrogen on bone loss in postmenopausal women. We performed a randomized double‐blind placebo‐controlled study to evaluate and compare with hormone‐replacement therapy (HRT) the effect of the phytoestrogen genistein on bone metabolism and bone mineral density (BMD) in postmenopausal women. Participants were 90 healthy ambulatory women who were 47–57 years of age, with a BMD at the femoral neck of <0.795 g/cm2. After a 4‐week stabilization on a standard fat‐reduced diet, participants of the study were randomly assigned to receive continuous HRT for 1 year (n = 30; 1 mg of 17β‐estradiol [E2] combined with 0.5 mg of norethisterone acetate), the phytoestrogen genistein (n = 30; 54 mg/day), or placebo (n = 30). Urinary excretion of pyridinoline (PYR) and deoxypyridinoline (DPYR) was not significantly modified by placebo administration either at 6 months or at 12 months. Genistein treatment significantly reduced the excretion of pyridinium cross‐links at 6 months (PYR = −54 ± 10%; DPYR = −55 ± 13%; p < 0.001) and 12 months (PYR = −42 ± 12%; DPYR = −44 ± 16%; p < 0.001). A similar and not statistically different decrease in excretion of pyridinium cross‐links was also observed in the postmenopausal women randomized to receive HRT. Placebo administration did not change the serum levels of the bone‐specific ALP (B‐ALP) and osteocalcin (bone Gla protein [BGP]). In contrast, administration of genistein markedly increased serum B‐ALP and BGP either at 6 months (B‐ALP = 23 ± 4%; BGP = 29 ± 11%; p < 0.005) or at 12 months (B‐ALP = 25 ± 7%; BGP = 37 ± 16%; p < 0.05). Postmenopausal women treated with HRT had, in contrast, decreased serum B‐ALP and BGP levels either at 6 months (B‐ALP = −17 ± 6%; BGP = −20 ± 9%; p < 0.001) or 12 months (B‐ALP = −20 ± 5%; BGP = −22 ± 10%; p < 0.001). Furthermore, at the end of the experimental period, genistein and HRT significantly increased BMD in the femur (femoral neck: genistein = 3.6 ± 3%, HRT = 2.4 ± 2%, placebo = −0.65 ± 0.1%, and p < 0.001) and lumbar spine (genistein = 3 ± 2%, HRT = 3.8 ± 2.7%, placebo = −1.6 ± 0.3%, and p < 0.001). This study confirms the genistein‐positive effects on bone loss already observed in the experimental models of osteoporosis and indicates that the phytoestrogen reduces bone resorption and increases bone formation in postmenopausal women.

The effect of the phytoestrogen genistein on plasma nitric oxide concentrations, endothelin-1 levels and endothelium dependent vasodilation in postmenopausal women

The phytoestrogen genistein improves endothelial dysfunction in ovariectomized rats through a nitric oxide-dependent mechanism. We investigated whether genistein alters the balance between the nitric oxide products and endothelin-1 and influences endothelium-dependent vasodilation in postmenopausal women. Sixty healthy postmenopausal women were enrolled in the study. A double-blind, placebo controlled, randomized design was employed. After a 4-week stabilization on a standard fat-reduced diet, participants to the study were randomly assigned to receive either genistein (n=30; 54 mg/day) or placebo (n=30). Flow-mediated, endothelium-dependent vasodilation of the brachial artery, plasma nitric oxide breakdown products and endothelin-1 levels were measured at baseline and after 6 months of genistein therapy. The mean baseline level of nitrites/nitrates was 22+/-10 micromol/l and increased to 41+/-10 micromol/ml after 6 months of treatment. The mean baseline plasma endothelin-1 level was 14+/-4 pg/ml and decreased to 7+/-1 pg/ml following 6 months of treatment with genistein. The mean baseline ratio of nitric oxide to endothelin also significantly increased at the end of treatment. Flow-mediated, endothelium-dependent vasodilation of the brachial artery was 3.9+/-0.8 mm at baseline and increased to 4.4+/-0.7 mm after 6 months of treatment. Placebo-treated women showed no changes in plasma nitrites/nitrates, endothelin-1 levels and flow-mediated vasodilation. Genistein therapy improves flow-mediated endothelium dependent vasodilation in healthy postmenopausal women. This improvement may be mediated by a direct effect of genistein on the vascular function and could be the result of an increased ratio of nitric oxide to endothelin.

Effect of genistein on endothelial function in postmenopausal women: a randomized, double-blind, controlled study

PURPOSE Genistein, a phytoestrogen found in soybeans, corrects endothelial dysfunction induced by oophorectomy in animals. Using a double-blind, controlled, randomized design, we evaluated its effects on endothelial function in women. METHODS We enrolled 79 healthy postmenopausal women (mean [+/- SD] age, 56 +/- 4 years) and randomly assigned them to receive continuous estrogen/progestin therapy (n = 26; 17beta-estradiol [1 mg/d] combined with norethisterone acetate [0.5 mg/d]), genistein (n = 27; 54 mg/d), or placebo (n = 26). Brachial artery flow-mediated, endothelium-dependent vasodilation and plasma levels of nitrites/nitrates (a marker of nitric oxide metabolism) and endothelin-1 were measured at baseline and after 1 year of therapy. RESULTS Treatment with genistein increased levels of nitrites/nitrates (mean increase, 21 micromol/L; 95% confidence interval [CI]: 15 to 26 micromol/L; P <0.001 vs. placebo); estrogen/progestin therapy caused similar changes (P <0.001 vs. placebo). Plasma endothelin-1 levels decreased following 12 months of genistein (mean decrease, 7 pg/mL; 95% CI: 3 to 10 pg/mL; P <0.001 vs. placebo) and after 12 months of estrogen/progestin (P <0.001 vs. placebo). When compared with placebo, brachial artery flow-mediated dilation was improved by genistein (mean increase, 5.5%; 95% CI: 3.9% to 7.0%; P <0.001) and by estrogen/progestin (P <0.001). There were no significant differences between estrogen and genistein for any of these parameters (all P >0.4). CONCLUSION One year of genistein therapy improves endothelium function in postmenopausal women to a similar extent as does an estrogen/progestin regimen.

Serum levels of osteoprotegerin and RANKL in patients with ST elevation acute myocardial infarction.

OPG (osteoprotegerin) has been suggested to have an important role in atherogenesis and vascular calcification. In the present study, we have investigated serum OPG and RANKL (receptor activator of nuclear factor kappaB ligand) concentrations in patients with ST elevation AMI (acute myocardial infarction) and established CAD (coronary artery disease). OPG and RANKL were measured in 58 male patients hospitalized in the coronary care unit with ST elevation AMI, in 52 asymptomatic male patients with an established diagnosis of CAD and in 52 healthy male controls. These last two groups were matched with the AMI patients for age and body mass index. OPG was significantly (P<0.05) higher in patients with AMI at 1 h after AMI (8.04+/-4.86 pmol/l) than in both patients with established CAD (4.92+/-1.65 pmol/l) and healthy subjects (3.15+/-1.01 pmol/l). Subjects with established CAD had significantly (P<0.05) increased OPG levels compared with controls. RANKL levels in patients with established CAD (0.02+/-0.05 pmol/l) and with AMI (0.11+/-0.4 pmol/l) were significantly (P<0.05) lower compared with controls (0.32+/-0.35 pmol/l). In the AMI group, OPG decreased significantly (P<0.05) at 1 and 4 weeks after infarction (8.04+/-4.86 compared with 6.38+/-3.87 and 6.55+/-2.6 pmol/l respectively), but OPG levels, either at 1 h or 1-4 weeks after AMI, remained significantly (P<0.05) higher compared with established CAD (4.92+/-1.65 pmol/l) and controls (3.15+/-1.01 pmol/l). Our data show for the first time that OPG levels are increased in ST elevation AMI within 1 h of infarction. Whether the increase in OPG is a consequence or a causal factor of plaque destabilization deserves further investigation.

Bisphosphonates in the treatment of thalassemia-induced osteoporosis

Abstract: The aim of our randomized, placebo-controlled study was to investigate the effects of 2 years’ daily oral administration of alendronate or intramuscular administration of clodronate every 10 days, on bone remodeling parameters and bone mineral density (BMD), safety and tolerability in a group of osteoporotic thalassemic patients. Twenty-five young patients (mean age 26.6 ± 7.1 years) with beta-thalassemia major were randomly divided to receive placebo or 100 mg of clodronate intramuscularly every 10 days or 10 mg of alendronate per os daily. All patients took 500 mg of elemental calcium and 400 IU cholecalciferol in the evening at meal time. After 2 years, pyridinium crosslinks, which are bone resorption markers, did not differ significantly from baseline values in the placebo group, whereas they had decreased significantly in the clodronate and alendronate groups. Osteocalcin, a bone formation marker, did not change significantly in the placebo group, whereas it decreased slightly, but not significantly, in the clodronate and alendronate groups after 12 and 24 months. At the end of the study, the lumbar spine BMD had decreased significantly in the placebo group; it did not change significantly in the clodronate group; in the alendronate group it had increased but not significantly, whereas the increase was significant with respect to the placebo group. Femoral neck BMD decreased significantly in the placebo group; it did not change significantly in the clodronate group, but increased significantly in the alendronate group. No relevant side effects were recorded during our study. In conclusion, in patients with thalassemia-induced osteoporosis, the daily administration of alendronate significantly increases BMD, the most important predictor of the risk of fracture at several sites. Clodronate treatment at our dosage is ineffective in this pathology in spite of the good compliance of patients.

Effects of the phytoestrogen genistein on cardiovascular risk factors in postmenopausal women.

Objective: The phytoestrogen genistein has been shown to be the most efficacious in clinical and experimental studies. We studied whether genistein treatment affects some cardiovascular risk markers in postmenopausal women. Design: Sixty healthy postmenopausal women, who were 52 to 60 years of age, were enrolled in a 6-month double-blind, placebo-controlled, randomized study. After a 4-week stabilization on a standard fat-reduced diet, participants were randomly assigned to receive either genistein (n = 30; 54 mg/d) or placebo (n = 30). At baseline and after a 6-month treatment, we measured fasting glucose, insulin, insulin resistance (HOMA-IR), osteoprotegerin (OPG), fibrinogen, and sex hormone-binding globulin (SHBG). Results: By comparison with placebo, genistein treatment decreased significantly fasting glucose (genistein = −8.7 ± 2.3%; placebo = 3.2 ± 2.3%; P < 0.001), fasting insulin (genistein = −12 ± 3.33%; placebo = 36 ± 3.29%; P < 0.001), and HOMA-IR (genistein = −14 ± 5.8%; placebo = 42 ± 0.6%; P < 0.001). After genistein-treatment, fibrinogen decreased (genistein = 3.18 ± 0.12 g/L; placebo = 3.83 ± 0.04 g/L; P < 0.001) with respect to placebo. In the genistein group, serum OPG was lower (−2 ± 0.3%) than in placebo (9 ± 1.5%; P < 0.001), and serum SHBG was higher (63 ± 3.8 nmol/L) compared with placebo (53 ± 2.9 nmol/L; P < 0.05). Conclusion: Our study suggests that genistein may have a favorable effect on some cardiovascular markers.

Cardiovascular effects of the phytoestrogen genistein.

Phytoestrogenic molecules have received a great deal of attention over the last few years because of their potentially preventive roles against a few of todays most prevalent chronic diseases, namely cardiovascular diseases, osteoporosis and hormone related cancers. Of the several phytoestrogens, genistein in particular has been shown to be the most efficacious in animal models and experimental studies. Genistein in vitro relaxes rat arteries by a nitric oxide dependent mechanism and enhances the dilator response to acetylcholine of atherosclerotic arteries. Genistein supplementation improves endothelial dysfunction induced by oophorectomy in rats and reduces infarct size in an experimental model of myocardial ischaemia-reperfusion injury. Furthermore, genistein in postmenopausal women increases plasma nitric oxide breakdown products, reduces endothelin-1 levels and improves endothelial dependent vasodilation in post-menopausal women. All these findings, taken together, would suggest that this molecule might represent an attractive alternative for cardiovascular protection.

The effect of the phytoestrogen genistein and hormone replacement therapy on homocysteine and C-reactive protein level in postmenopausal women

Background.  The aim of the study was to evaluate the effect, in postmenopausal women, of the phytoestrogen genistein and hormone replacement therapy (HRT) on circulating two independent factors of cardiovascular risk: homocysteine and C‐reactive protein (CRP).

Osteoporosis and β-thalassemia major: Role of the IGF-I/IGFBP-III axis

Patients with β-thalassaemia major are susceptible to osteopenia due to several factors which interfere with bone remodeling. It is known that bone metabolism and skeletal consolidation result from a complex sequence of hormonal changes, where the concerted actions of GH, IGFI and sex hormones and their receptors, are responsible for the timing and attainment of skeletal consolidation. IGF-I and the corresponding binding protein (IGFBP-III), markers of bone metabolism and lumbar and femoral neck BMD were measured in 28 adult patients, undergoing hormonal replacement and chelation therapy and a hypertransfusion program, with β-thalassaemia major (12 males with mean age 22.5±3.1 and 16 females with mean age 27.5±8.2), and in 28 healthy volunteers matched for age, anthropometric features and sex to the patients. BMD values, both at lumbar and femoral neck level were significantly lower (p<0.001 and p<0.05) by 18.7 and 4.2% respectively, in patients than in the controls. Markers of bone resorption [pyridinoline (Pyr) 78.1±15.7 vs 47.5±11.2 pmol/μmol urinary creatinine, p<0.001 and deoxypyridinoline (D-Pyr) 21.9±3.5 vs 14.5±5.4 pmol/μmol urinary creatinine, p<0.001] were higher in patients than in controls, whereas the marker of bone formation was slightly lower [osteocalcin (BGP) 3.8±0.6 vs4.6±1.7 pmol/ml, p<0.05]. Plasma levels of IGF-I (21.07±5.12 vs 35.25±8.33 nmol/ml, p<0.001) and IGF binding protein III (IGFBP-III) (1.9±0.4 vs2.5±0.1 mg/ml, p<0.001) were lower in patients than in controls and positively correlated with BMD L2-L4 (r=0.57, p<0.05 and r=0.47, p<0.05 respectively), BMD neck (r=0.40, p<0.05 and r=0.34, p<0.05 respectively) and BGP (r=0.52, p<0.05 and r=0.34, p<0.05 respectively). Our β-thalassaemic patients, in spite of normalizing hemoglobin levels, adequate hormone replacement and chelation therapies, showed osteopenia and an unbalanced bone turnover with an increased resorptive phase and a decreased formation phase probably correlated to low levels of IGF-I and IGFBP-III observed in our study.

Neurokinin B and nitric oxide plasma levels in pre‐eclampsia and isolated intrauterine growth restriction

Objective  To verify if neurokinin B plasma level is increased in pre‐eclampsia and IUGR. Also, to ascertain if there is a correlation between neurokinin B plasma level and nitric oxide production.