Carla Lubrano

Effects of the Phytoestrogen Genistein on Bone Metabolism in Osteopenic Postmenopausal Women: A Randomized Trial

Context Women seeking alternative treatments to preserve bone often use phytoestrogens, but evidence of their effectiveness is lacking. Phytoestrogens are found in soy products. Genistein is a phytoestrogen with a structure similar to that of 17-estradiol. Contribution This randomized trial compared genistein, 54 mg/d, with placebo for 24 months in 389 osteopenic postmenopausal women. Increases in bone mineral density were greater with genistein than with placebo. Genistein also had favorable effects on markers of bone metabolism. Genistein did not increase endometrial thickness, but it did cause gastrointestinal side effects. Implications Genistein appears to have a favorable effect on markers of bone health in osteopenic postmenopausal women. Studies of its effect on fractures are needed. The Editors Postmenopausal osteoporosis is caused by a sharp decrease in estrogen levels that leads to an increased rate of bone remodeling (13). Currently available treatments for postmenopausal osteoporosis include hormone replacement therapy; calcitonin; bisphosphonates; and selective estrogen receptor modulators, such as raloxifene (4, 5). Although hormone replacement therapy is effective in reducing postmenopausal bone loss (68), it is associated with a higher risk for breast, endometrial, and ovarian cancer; cardiovascular disease; venous thromboembolism; and stroke (810). Epidemiologic data indicate that women who ingest high amounts of phytoestrogens, particularly isoflavones in soy products, have less risk for osteoporosis than do those who consume a typical Western diet (1113). Consequently, many women use phytoestrogens to maintain bone density. Genistein, an isoflavone phytoestrogen that is abundant in soybean products, structurally resembles 17-estradiol (14). As a natural selective estrogen receptor modulator, genistein may positively regulate bone cell metabolism without harmful estrogenic activity in the breast and uterus. This safe profile results from the greater affinity of genistein for estrogen receptor-, which is more abundant in bone, than for estrogen receptor-, which is abundant in reproductive tissue. Observational studies suggest that postmenopausal Asian women who consume diets high in isoflavones have a lower rate of fracture than that in other groups (15, 16). However, the mechanism of action of genistein on bone is not yet fully understood. In postmenopausal women, treatment with genistein (54 mg/d) increased bone mineral density (BMD) at the lumbar spine and femoral neck with no clinically significant adverse effects on the breast and uterus (17). In the same cohort, genistein decreased the ratio of soluble receptor activator of nuclear factor-B ligand to osteoprotegerin, which may partly account for its positive effects on BMD (18). These investigations were the first to evaluate the effects of purified, standardized genistein on bone health, but they were short in duration and included only 90 patients. One published trial assessed the effect of isoflavones on BMD in postmenopausal women, but it compared isoflavone-rich soy milk (containing only a small amount of genistein) with natural transdermal progesterone (19). Other studies of pure genistein from our research group have focused on cardiovascular outcomes or menopausal symptoms rather than on bone health (2022). We performed a randomized, placebo-controlled trial of the effects of pure genistein on bone density and bone metabolism over 24 months in a larger cohort of osteopenic postmenopausal women. Methods Design and Setting The study protocol is consistent with the principles of the Declaration of Helsinki, and participants gave written informed consent. Participants were recruited from women reporting to the Center for Osteoporosis in the Department of Internal Medicine and the Center for Menopause in the Department of Obstetrical and Gynecological Sciences, University of Messina (Messina, Italy), and to the Department of Medical Physiopathology, University La Sapienza (Rome, Italy). Three hundred eighty-nine women met the inclusion criteria and agreed to participate (Figure 1). Figure 1. Study flow diagram. Participants Participants were women 49 to 67 years of age who had been postmenopausal for at least 12 months at baseline, were in good general health, had not had a menstrual period in the preceding year, had not undergone surgically induced menopause, and had a follicle-stimulating hormone level greater than 50 IU/L and a serum 17-estradiol level of 100 pmol/L or less (27 pg/mL). At the start of the study, a complete family history was obtained, physical examination and laboratory evaluation (chemical analytes and hematologic measurements) were performed, and BMD was measured at the lumbar spine and femoral neck. Exclusion criteria were clinical or laboratory evidence of confounding systemic diseases, such as cardiovascular, hepatic, or renal disorders; coagulopathy; use of oral or transdermal estrogen, progestin, androgens, selective estrogen receptor modulators, or other steroids; use of biphosphonates, cholesterol-lowering therapy, or cardiovascular medications (including antihypertensive drugs) in the preceding 6 months; smoking habit of more than 2 cigarettes daily; treatment in the preceding year with any drug that could have affected the skeleton; family history of estrogen-dependent cancer; and BMD at the femoral neck greater than 0.795 g/cm2 (which corresponds to a T-score of 1.0 SD). Randomization and Intervention We assigned patients to groups by using a computer-generated randomization sequence with a permuted block size of 4, stratified by center. After a 4-week stabilization period during which participants received a standard low-soy, reduced-fat diet, participants were assigned to receive genistein (n= 198), 54 mg/d in 2 tablets (Laboratori Plants, Messina, Italy), or placebo (n= 191) (Figure 1). The biological effects of phytoestrogen intake are described elsewhere (23). No patient withdrew from the study during the stabilization period. The purity of genistein was 98%. Placebo and genistein tablets were identical in appearance and taste. Both genistein and placebo tablets contained calcium carbonate (500 mg) and vitamin D (400 IU). All participants were counseled on an isocaloric, reduced-fat diet composed of 25% to 30% energy from fat, less than 10% energy from saturated fatty acids, 55% to 60% energy from carbohydrates, and 15% energy from protein, with a cholesterol intake less than 300 mg/d and fiber intake of 35 g/d or greater. Recommended daily caloric intake was based on body size and was calculated by using the HarrisBenedict equation. We used this diet during the stabilization period to ensure that all participants had the same energy intake and to avoid interference with the lipid profile. The intake of soy products, legumes, or other nutrient supplements was prohibited. The isoflavone intake before randomization, as assessed by using a food-frequency questionnaire, was 1 to 2 mg/d. This intake has been shown to be typical in Western populations (24). Participants used this diet throughout the study, and adherence was reinforced by a nutritionist. Diet and body mass index were evaluated in all participants during follow-up. Primary Outcome The BMD at the anteroposterior lumbar spine and femoral neck was measured by using dual-energy x-ray absorptiometry (Hologic QDR 4500 W, Technologic, Turin, Italy) at baseline and after 12 and 24 months of treatment. The instrument was calibrated daily according to the manufacturers instructions. Reproducibility was calculated as a coefficient of variation obtained by weekly measurements of a standard phantom on the instrument and by repeated measurements obtained in 3 patients of different ages. The coefficient of variation of our instrument is 0.5% with the standard phantom; in vivo, we calculated a coefficient of variation of 1.1% for the lumbar spine and 1.5% for the femoral neck. Secondary Outcomes Bone Resorption Markers At baseline, 12 months, and 24 months, a 2-hour fasting morning urine sample was collected at the same time of day to assess urinary excretion of pyridinium crosslinks (pyridinoline and deoxypyridinoline). Pyridinoline (normal range, 26 to 91 pmol/mol creatinine) and deoxypyridinoline (normal range, 3 to 21 pmol/mol creatinine) were measured by using high-performance liquid chromatography (Bio-Rad Laboratories, Hercules, California). Bone Formation and Bone Growth Markers and Other Variables After an overnight fast, venous blood samples were collected between 8 a.m. and 9 a.m. through a polyethylene catheter inserted in a forearm vein. The serum was separated from the blood corpuscles by centrifugation and kept frozen at 70C until analysis for bone formation and bone growth markers, calcium, intact parathyroid hormone, 25-hydroxyvitamin D3, 17-estradiol, follicle-stimulating hormone, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides. Serum bone-specific alkaline phosphatase (normal range, 8.5 to 17.9 g/L) and insulin-like growth factor I (normal range, 9.6 to 21.2 nmol/L) were measured by using an immunoenzymatic assay (Pantec, Turin, Italy). Serum calcium (normal range, 2.25 to 2.75 mmol/L [9 to 11 mg/dL]), serum phosphorus (normal range, 1.13 to 1.45 mmol/L [3.5 to 4.5 mg/dL]), and urinary creatinine (130 to 220 molkg1d1 [14.71 to 24.89 mg/kg of body weight per day]) were measured by using automated routine procedures. Parathyroid hormone (normal range, 12 to 100 pg/dL), 25-hydroxyvitamin D3 (normal range, 1.25 to 7.5 nmol/L), and follicle-stimulating hormone (normal range, 21 to 153 IU/L in the postmenopausal phase) were measured by using high-performance liquid chromatography (Bio-Rad Laboratories). 17-Estradiol (normal range, 37 to 110 pmol/L in the postmenopausal phase) was evaluated by using a solid-phase immunoassay (Roche Diagnostics, Monza, Italy). Total cholesterol,

Breast Safety and Efficacy of Genistein Aglycone for Postmenopausal Bone Loss: A Follow-Up Study

CONTEXT Genistein aglycone improves bone metabolism in women. However, questions about the long-term safety of genistein on breast as well as its continued efficacy still remain. OBJECTIVE We assessed the continued safety profile of genistein aglycone on breast and endometrium and its effects on bone after 3 yr of therapy. DESIGN The parent study was a randomized, double-blind, placebo-controlled trial involving 389 osteopenic, postmenopausal women for 24-months. Subsequently, a subcohort (138 patients) continued therapy for an additional year. PATIENTS AND INTERVENTIONS Participants received 54 mg of genistein aglycone daily (n = 71) or placebo (n = 67). Both treatment arms received calcium and vitamin D(3) in therapeutic doses. MAIN OUTCOMES Mammographic density was assessed at baseline, 24 and 36 months by visual classification scale and digitized quantification. BRCA1 and BRCA2, sister chromatid exchange, and endometrial thickness were also evaluated. Lumbar spine and femoral neck bone mineral density were also assessed. Secondary outcomes were biochemical levels of bone markers. RESULTS After 36 months, genistein did not significantly change mammographic breast density or endometrial thickness, BRCA1 and BRCA2 expression was preserved, whereas sister chromatid exchange was reduced compared with placebo. Bone mineral density increases were greater with genistein for both femoral neck and lumbar spine compared to placebo. Genistein also significantly reduced pyridinoline, as well as serum carboxy-terminal cross-linking telopeptide and soluble receptor activator of NF-kappaB ligand while increasing bone-specific alkaline phosphatase, IGF-I, and osteoprotegerin levels. There were no differences in discomfort or adverse events between groups. CONCLUSIONS After 3 yr of treatment, genistein exhibited a promising safety profile with positive effects on bone formation in a cohort of osteopenic, postmenopausal women.

OPG and sRANKL Serum Concentrations in Osteopenic, Postmenopausal Women After 2‐Year Genistein Administration

Introduction: RANKL and its decoy receptor osteoprotegerin (OPG) constitute a complex physiological mediator system involved in the regulation of bone resorption and may be responsible for the homeostatic mechanism of normal bone remodeling. Genistein, an isoflavone representing 1–5% of total phytoestrogen content in soybean products, may positively regulate cellular bone metabolism, but its mechanism of action on bone is not yet fully understood.

Biological definition of multiple chemical sensitivity from redox state and cytokine profiling and not from polymorphisms of xenobiotic-metabolizing enzymes

BACKGROUND Multiple chemical sensitivity (MCS) is a poorly clinically and biologically defined environment-associated syndrome. Although dysfunctions of phase I/phase II metabolizing enzymes and redox imbalance have been hypothesized, corresponding genetic and metabolic parameters in MCS have not been systematically examined. OBJECTIVES We sought for genetic, immunological, and metabolic markers in MCS. METHODS We genotyped patients with diagnosis of MCS, suspected MCS and Italian healthy controls for allelic variants of cytochrome P450 isoforms (CYP2C9, CYP2C19, CYP2D6, and CYP3A5), UDP-glucuronosyl transferase (UGT1A1), and glutathione S-transferases (GSTP1, GSTM1, and GSTT1). Erythrocyte membrane fatty acids, antioxidant (catalase, superoxide dismutase (SOD)) and glutathione metabolizing (GST, glutathione peroxidase (Gpx)) enzymes, whole blood chemiluminescence, total antioxidant capacity, levels of nitrites/nitrates, glutathione, HNE-protein adducts, and a wide spectrum of cytokines in the plasma were determined. RESULTS Allele and genotype frequencies of CYPs, UGT, GSTM, GSTT, and GSTP were similar in the Italian MCS patients and in the control populations. The activities of erythrocyte catalase and GST were lower, whereas Gpx was higher than normal. Both reduced and oxidised glutathione were decreased, whereas nitrites/nitrates were increased in the MCS groups. The MCS fatty acid profile was shifted to saturated compartment and IFNgamma, IL-8, IL-10, MCP-1, PDGFbb, and VEGF were increased. CONCLUSIONS Altered redox and cytokine patterns suggest inhibition of expression/activity of metabolizing and antioxidant enzymes in MCS. Metabolic parameters indicating accelerated lipid oxidation, increased nitric oxide production and glutathione depletion in combination with increased plasma inflammatory cytokines should be considered in biological definition and diagnosis of MCS.

Comparison of Changes in Lipid Profile after Bilio-intestinal Bypass and Gastric Banding in Patients with Morbid Obesity

Background: The presence of hypercholesterolemia is currently not considered a selection criteria for performing gastric restrictive or diversionary bariatric surgery. Methods: We prospectively investigated the effects of the bilio-intestinal bypass (BI-bypass) with a wide cholecysto-jejunal anastomosis and of adjustable gastric banding (AGB) on blood lipid concentrations in obese patients. To clarify the mechanism of the hypocholesterolemic effect of the BI-bypass, daily fecal sterol excretion was measured by gas-liquid chromatography (GLC). Results: At 1 year after BI-bypass compared to baseline, the hypercholesterolemic (n=18) and the normocholesterolemic (n=19) patients significantly reduced total (−38% and −27%, respectively), LDL (−47% and −24%, respectively) and HDL (−11% and −13%, respectively) cholesterol and total / HDL cholesterol ratio (−25% and −13%, respectively). At 1 year after AGB, the total / HDL cholesterol ratio was significantly decreased (−11%) compared to baseline in hypercholesterolemic (n=12) but not in normocholesterolemic (n=6) patients, while total and LDL cholesterol were not affected in both groups. At 3 years after BI-bypass compared to baseline, the hypercholesterolemic (n=9) and the normocholesterolemic (n=11) patients significantly reduced total (−43% and −28%, respectively) and LDL (−53% and −29%, respectively) cholesterol and total / HDL cholesterol ratio (−38% and −21%, respectively). The BI-bypass induced a significant (P <0.005; n=7) 6-fold increase in mean fecal cholesterol output. Conclusions: The BI-bypass but not the AGB leads to a persistent and marked beneficial effect on blood LDL cholesterol associated with an increased cholesterol fecal output. BI-bypass but not AGB is indicated in morbidly obese patients with hypercholesterolemia.

Efficacy of genistein aglycone on some cardiovascular risk factors and homocysteine levels: A follow-up study *

BACKGROUND AND AIM Recent evidence suggests that genistein aglycone may act beneficially on surrogate cardiovascular risk markers in postmenopausal women. We assessed the effects of genistein aglycone on some cardiovascular risk factors and homocysteine levels after 3-years of continued therapy in a cohort of osteopenic, postmenopausal women. METHODS AND RESULTS The parent study was a randomized, double-blind, placebo-controlled trial involving 389 postmenopausal women with low bone mass for 24 months. Subsequently, a subcohort (138 patients) continued therapy for an additional year. Participants received 54mg of genistein aglycone (n=71) or placebo (n=67), daily. Both arms received calcium and vitamin D(3) in therapeutic doses. Moreover, 4 weeks before randomization procedures and during our follow-up study, all patients received dietary instructions in an isocaloric fat-restricted diet. Blood lipid profiles, fasting glucose and insulin, insulin resistance (HOMA-IR), fibrinogen, osteoprotegerin (OPG) and homocysteine at baseline and after 24 and 36 months of treatment were measured. Compared to placebo, genistein significantly decreased fasting glucose and insulin, HOMA-IR, fibrinogen and homocysteine after 24 and 36 months of treatment. By contrast, isoflavone administration did not affect high-density lipoprotein cholesterol and triglycerides though serum OPG was higher in the genistein recipients. There were no differences in adverse events or discomfort between groups. Results on routine biochemical, liver function, and hematologic testing did not change over time in placebo or genistein group. CONCLUSIONS After 3-years of treatment, genistein aglycone plus calcium, vitamin D(3) and a healthy diet showed positive effects on some cardiovascular risk factors and homocysteine levels in a cohort of postmenopausal women with low bone mass.

Negative association between trunk fat, insulin resistance and skeleton in obese women

AIM To evaluate the potential interference of trunk fat (TF) mass on metabolic and skeletal metabolism. METHODS In this cross-sectional study, 340 obese women (mean age: 44.8 ± 14 years; body mass index: 36.0 ± 5.9 kg/m(2)) were included. Patients were evaluated for serum vitamin D, osteocalcin (OSCA), inflammatory markers, lipids, glucose and insulin (homeostasis model assessment of insulin resistance, HOMA-IR) levels, and hormones profile. Moreover, all patients underwent measurements of bone mineral density (BMD; at lumbar and hip site) and body composition (lean mass, total and trunk fat mass) by dual-energy X-ray absorptiometry. RESULTS Data showed that: (1) high TF mass was inversely correlated with low BMD both at lumbar (P < 0.001) and hip (P < 0.01) sites and with serum vitamin D (P < 0.0005), OSCA (P < 0.0001) and insulin-like growth factor-1 (IGF-1; P < 0.0001) levels; (2) a positive correlation was found between TF and HOMA-IR (P < 0.01), fibrinogen (P < 0.0001) and erythrocyte sedimentation rate (P < 0.0001); (3) vitamin D levels were directly correlated with IGF-1 (P < 0.0005), lumbar (P < 0.006) and hip (P < 0.01) BMD; and (4) inversely with HOMA-IR (P < 0.001) and fibrinogen (P < 0.0005).Multivariate analysis demonstrated that only vitamin D was independent of TF variable. CONCLUSION In obese women, TF negatively correlates with BMD independently from vitamin D levels. Reduced IGF-1 and increased inflammatory markers might be some important determinants that account for this relationship.

Relationships between Body Fat Distribution, Epicardial Fat and Obstructive Sleep Apnea in Obese Patients with and without Metabolic Syndrome

Background Obstructive sleep apnea (OSA) and metabolic syndrome, both closely related to obesity, often coexist in affected individuals; however, body mass index is not an accurate indicator of body fat and thus is not a good predictor of OSA and other comorbidities. The aim of this study was to investigate whether the occurrence of OSA could be associated with an altered body fat distribution and a more evident cardio metabolic risk independently from obesity and metabolic syndrome. Methods and Results 171 consecutive patients (58 men and 113 women) were included in the study and underwent overnight polysomnography. Anthropometric data, blood pressure, lipid profile, glycaemic parameters were recorded. Body composition by DXA, two-dimensional echocardiography and carotid intima/media thickness measurement were performed. 67 patients (39.2%) had no OSA and 104 (60.8%) had OSA. The percentage of patients with metabolic syndrome was significantly higher among OSA patients (65.4%) that were older, heavier and showed a bigger and fatter heart compared to the control group. Upper body fat deposition index , the ratio between upper body fat (head, arms and trunk fat in kilograms) and lower body fat (legs fat in kilograms), was significantly increased in the OSA patients and significantly related to epicardial fat thickness. In patients with metabolic syndrome, multivariate regression analyses showed that upper body fat deposition index and epicardial fat showed the best association with OSA. Conclusion The occurrence of OSA in obese people is more closely related to cardiac adiposity and to abnormal fat distribution rather than to the absolute amount of adipose tissue. In patients with metabolic syndrome the severity of OSA is associated with increase in left ventricular mass and carotid intima/media thickness.

Metabolic or bariatric surgery? Long-term effects of malabsorptive vs restrictive bariatric techniques on body composition and cardiometabolic risk factors

Background:Obesity is an increasing health problem and surgery seems to be the only treatment effective in achieving weight loss without relapse. Among bariatric techniques, many differences exist in terms of weight loss and resolution of comorbidities. Up to now, there are no prospective studies comparing long-term effects of malabsorptive vs restrictive techniques.Objective:In this study, cardiometabolic risk factors and body composition changes after malabsorptive biliointestinal bypass (BIBP) and restrictive laparoscopic adjustable gastric banding (LAGB) were compared during a 4-year follow-up.Design:Prospective, case–control and cohort study.Patients:In all, 80 obese subjects, matched for weight and age. Altogether, 40 patients underwent BIBP and 40 underwent LAGB.Measurements:Weight, body composition, fasting and post-loading plasma glucose and insulin, homeostatic model assessment index (HOMA-I), lipid profile, blood pressure (BP), erythrocyte sedimentation rate and fibrinogen were monitored at baseline, 12 and 48 months.Results:At 12 months after surgery, a significant reduction in body mass index, total fat mass (FM), trunk FM (trFM), trFM/legs FM (lFM) ratio (trFM/lFM), triglycerides, BP and inflammation markers was observed in both groups. BIBP patients showed a significant reduction in total cholesterol (Tot-C), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C), whereas the LAGB group showed a significant increase of HDL-C. A further improvement of all the parameters evaluated was seen in the BIBP group at 48 months after surgery.Conclusions:Both bariatric procedures exerted positive effects on cardiometabolic risk factors and on weight loss in the population studied, but on the long-term period, HOMA-I, Tot-C/HDL-C ratio and body composition improvements were more evident after BIBP. We conclude that malabsorptive BIBP seems to be more effective than LAGB in treating visceral obesity and its metabolic complications

Obesity and Metabolic Comorbidities: Environmental Diseases?

Obesity and metabolic comorbidities represent increasing health problems. Endocrine disrupting compounds (EDCs) are exogenous agents that change endocrine function and cause adverse health effects. Most EDCs are synthetic chemicals; some are natural food components as phytoestrogens. People are exposed to complex mixtures of chemicals throughout their lives. EDCs impact hormone-dependent metabolic systems and brain function. Laboratory and human studies provide compelling evidence that human chemical contamination can play a role in obesity epidemic. Chemical exposures may increase the risk of obesity by altering the differentiation of adipocytes. EDCs can alter methylation patterns and normal epigenetic programming in cells. Oxidative stress may be induced by many of these chemicals, and accumulating evidence indicates that it plays important roles in the etiology of chronic diseases. The individual sensitivity to chemicals is variable, depending on environment and ability to metabolize hazardous chemicals. A number of genes, especially those representing antioxidant and detoxification pathways, have potential application as biomarkers of risk assessment. The potential health effects of combined exposures make the risk assessment process more complex compared to the assessment of single chemicals. Techniques and methods need to be further developed to fill data gaps and increase the knowledge on harmful exposure combinations.