Effect of long-term administration of cross-sex hormone therapy on serum and urinary uric acid in transsexual persons

Multigenerations assessment of dietary nucleotides consumption in weaned rats

With the multifaceted activities of nucleotides, there is a history of safe consumption of dietary nucleotides (NTs) in the human diet. This study investigated the multigenerations cumulative toxicity on rats' development after weaning. Weaning rats (F0) were fed with NTs at the dosage of 0.01, 0.04, 0.16, 0.64, and 1.28% (wt/wt) for 90 days and then mated for 1:1 pattern. The offspring was F1. F1 rats were fed with NTs for 90 days after weaning. Afterwards, F1 go on to the second reproductive part. We repeated the above process, until F3 rats were born. We observed the weight, food consumption in the whole experiment, and detected the blood indicators and organ pathology at the terminal. No abnormal reaction, behavior disorder, and organ pathology related to toxic symptom were observed in NTs-treated groups. Weight gain and diet utilization ratio of males in each NTs group had significant increase after weaning (p < 0.05). With the exception of decrease in uric acid (p < 0.05) of NTs male, there were no differences between the control and NTs groups in blood indicators. NTs could promote early growth and development of rats after weaning, especially in males.

Medical management of adult transsexual persons

Gender identity disorder (GID), or transsexualism, is an increasingly recognized medical condition with an expanding body of medical literature to support the use of established therapeutic guidelines. Transsexualism can be effectively managed through exogenous cross-sex hormone administration used to induce development of desired sex characteristics, as well as use of other agents, such as aldosterone antagonists, aimed at decreasing physical characteristics of the undesired sex. Many complications can arise with the use of the available therapies, and these must be considered before determining the appropriate course of action. This review describes methods, including both pharmacotherapy and surgical interventions, for effective medical management of both male and female adults with GID. In addition, specific goals of therapy as well as safety aspects with long-term use of pharmacotherapeutic agents are discussed. This review also discusses some special considerations for treating patients with significant, yet common, comorbid diseases such as human immunodeficiency virus infection, acquired immunodeficiency syndrome, and viral hepatitis, as these conditions may complicate the clinical course and preclude some patients from using certain therapies. Pharmacist involvement in the management of transsexualism can be extremely beneficial to patients and other health care providers. Pharmacists can help determine the appropriate therapy, optimize dosages, monitor for adverse effects, and educate patients on what to expect during their therapy. Pharmacists should become knowledgeable about guidelines and current literature on transsexualism, understand the monitoring parameters for safe and effective therapy, and establish themselves as partners in the collaborative management of this disorder.

Effects of high-fructose corn syrup and sucrose on the pharmacokinetics of fructose and acute metabolic and hemodynamic responses in healthy subjects

It is unclear whether high-fructose corn syrup (HFCS), which contains a higher amount of fructose and provides an immediate source of free fructose, induces greater systemic concentrations of fructose as compared with sucrose. It is also unclear whether exposure to higher levels of fructose leads to increased fructose-induced adverse effects. The objective was to prospectively compare the effects of HFCS- vs sucrose-sweetened soft drinks on acute metabolic and hemodynamic effects. Forty men and women consumed 24 oz of HFCS- or sucrose-sweetened beverages in a randomized crossover design study. Blood and urine samples were collected over 6 hours. Blood pressure, heart rate, fructose, and a variety of other metabolic biomarkers were measured. Fructose area under the curve and maximum concentration, dose-normalized glucose area under the curve and maximum concentration, relative bioavailability of glucose, changes in postprandial concentrations of serum uric acid, and systolic blood pressure maximum levels were higher when HFCS-sweetened beverages were consumed as compared with sucrose-sweetened beverages. Compared with sucrose, HFCS leads to greater fructose systemic exposure and significantly different acute metabolic effects.

Racial/ethnic and sex differences in the relationship between uric acid and metabolic syndrome in adolescents: an analysis of National Health and Nutrition Survey 1999-2006

Among adolescents, uric acid is associated with insulin resistance, hypertension, and the metabolic syndrome (MetS); and in adults, high uric acid levels are an independent risk factor for cardiovascular disease and diabetes. The objective was to determine whether the relationship of uric acid with MetS varies in adolescents by race/ethnicity and sex. We used linear regression to evaluate associations between uric acid and other MetS-associated clinical and laboratory measures among 3296 non-Hispanic white, non-Hispanic black, and Hispanic adolescents aged 12 to 19 years participating in the National Health and Nutrition Evaluation Survey (1999-2006). Overall, non-Hispanic white males and females had the highest uric acid levels among the 3 racial/ethnic groups. In each racial/ethnic group, there were higher uric acid levels for those adolescents with vs without MetS. However, the extent of the MetS-related increase in uric acid level varied by race and sex. Among males, MetS was associated with the greatest increases in uric acid among non-Hispanic whites. However, among females the MetS-related increase in uric acid was greater among non-Hispanic blacks and Hispanics. Non-Hispanic white females exhibited the lowest degrees of correlation between levels of uric acid and MetS-associated variables. Uric acid levels did not correlate with insulin levels in non-Hispanic white females. These data suggest that the relationship between uric acid and MetS varies by race/ethnicity and sex. In particular, non-Hispanic white males exhibit a strong relationship and non-Hispanic white females exhibit a relatively poor correlation between uric acid and MetS-related factors. These data may have implications for the use of uric acid as a marker of future risk among adolescents.

Reproductive factors and serum uric acid levels in females from the general population: the KORA F4 study

Objective

Hyperuricemia is associated with an increased risk of metabolic and cardiovascular diseases. There are pronounced sex differences in the levels of uric acid. It is largely unknown whether or not reproductive parameters which induce hormonal changes are responsible for this. We examined if there are associations between reproductive parameters and uric acid levels in a female population-based sample.

Methods

In this cross-sectional analysis, data of 1530 women aged 32 to 81 years participating in the KORA F4 study, conducted between 2006 and 2008 in Southern Germany were used. Reproductive parameters were obtained by standardized interviews. Uric acid levels were tested by the uricase method. The whole study sample and stratified in pre- and postmenopausal women was analyzed.

Results

Menopausal status and earlier age at menarche were associated with higher serum uric acid levels (age-adjusted: p-values 0.003, <0.001 respectively; after multivariable adjustment, including BMI: p-values 0.002, 0.036). A history of oral contraceptive use showed an association with uric acid levels only after multivariable adjustment (p-value 0.009). Hot flushes showed an association with uric acid levels only after age-adjustment (p-value 0.038), but lost significance after adding other confounders. Other reproductive factors, including parity, current or ever use of hormone replacement therapy, current use of oral contraceptives, hysterectomy, bilateral oophorectomy, or depressive mood related to menopausal transition were not associated with uric acid levels.

Conclusions

Postmenopausal status, earlier age at menarche and a history of oral contraceptive use were independently associated with higher serum uric acid concentrations in women from the general population. Further studies, especially longitudinal population-based studies investigating the relationship of female reproductive parameters with uric acid levels are necessary to confirm our findings.

Testosterone, SHBG and risk of type 2 diabetes in the second evaluation of the Pizarra cohort study

AIM

To evaluate the association between serum levels of testosterone, sex hormone-binding globulin (SHBG) and calculated bioavailable testosterone (bioT), and the risk of type 2 diabetes mellitus (T2D) in a prospective cohort from southern Spain (Pizarra study).

RESEARCH DESIGN AND METHODS

The study was performed in the Pizarra Cohort Study, a prospective study started in 1995 with a follow-up of 11 years. Anthropometric and metabolic variables were measured at baseline and at 6 and 11 years of follow-up. Total testosterone (TT), SHBG and calculated bioT were determined at the 6-year follow-up.

RESULTS

The levels of TT and bioT in men were negatively associated with the risk of obesity, T2D and the metabolic syndrome. In women, the levels of TT and bioT were associated positively with the risk of insulin resistance. The levels of SHBG were associated negatively with the risk of T2D, obesity and insulin resistance in both men and women. For all groups, the association was higher at the 11-year follow-up.

CONCLUSIONS

Low levels of testosterone and SHBG increase the risk of T2D in men, and high levels of testosterone increase the risk of insulin resistance in women. The association between TT levels and the risk of T2D is not completely independent of other variables, such as exposure time, adiposity, insulin resistance or SHBG levels. This study also shows that the different responses between men and women are probably because of the protective effect of SHBG, levels of which are higher in women than in men.

Uric acid as a factor in the metabolic syndrome

Hyperuricemia is a prevalent finding in patients presenting metabolic syndrome, although its clinical meaning is still controversial and often underestimated. Men and women have different serum urate levels at all ages, and the impact of hyperuricemia in cardiovascular and renal outcomes is generally associated with a worse prognosis in women. Recent studies also have called attention to another perspective on hyperuricemia, indicating that it may be not only a consequence of insulin resistance states but also a significant predictor of the development of metabolic syndrome. This review discusses recent evidence related to the clinical significance of hyperuricemia in both sexes and the potential benefits of lowering serum uric acid levels.

Mechanism and effects of glucose absorption during an oral glucose tolerance test among females and males

BACKGROUND

Several epidemiological studies revealed sex-specific differences during oral glucose tolerance tests (OGTTs), such as higher prevalence of glucose intolerance (i.e. increased glucose at the end of the OGTT) in females, which was not yet explained. Thus, we aimed to analyze sex-related distinctions on OGTT glucose metabolism, including gut absorption, in healthy humans.

METHODS

Females (n = 48) and males (n = 26) with comparable age (females, 45 ± 1 yr; males, 44 ± 2 yr) and body mass index (both, 25 ± 1 kg/m(2)) but different height (females, 166 ± 1 cm; males, 180 ± 2 cm; P < 0.000001), all normally glucose tolerant, as tested by frequently sampled, 3-h (75-g) OGTTs, underwent hyperinsulinemic [40 mU/(min · m(2))] isoglycemic clamp tests with simultaneous measurement of endogenous glucose (d-[6,6-(2)H(2)]glucose) production (EGP). EGP and glucose disappearance during OGTT were calculated from logarithmic relationships with clamp test insulin concentrations. After reliable model validation by double-tracer technique (r = 0.732; P < 0.007), we calculated and modeled gut glucose absorption (ABS).

RESULTS

Females showed lower (P < 0.05) fasting EGP [1.4 ± 0.1 mg/(kg · min)] than males [1.7 ± 0.1 mg/(kg · min)] but comparable whole-body insulin sensitivity in clamp tests [females, 8.1 ± 0.4 mg/(kg · min); males, 8.3 ± 0.6 mg/(kg · min)]. Plasma glucose OGTT concentrations were higher (P < 0.04) from 30-40 min in males but from 120-180 min in females. Glucose absorption rates were 21-46% increased in the initial 40 min in males but in females by 27-40% in the third hour (P < 0.05). Gut glucose half-life was markedly higher in females (79 ± 2 min) than in males (65 ± 3 min, P < 0.0001) and negatively related to body height (r = -0.481; P < 0.0001).

CONCLUSIONS

This study in healthy, glucose-tolerant humans shows for the first time different ABS rates during OGTT in women and men and a negative relationship between body height and gut glucose half-life. Prolonged ABS in females might therefore contribute to higher plasma glucose concentrations at the end of OGTT.

Gender-specific association of serum uric acid with metabolic syndrome and its components in juvenile obesity

BACKGROUND

Hyperuricemia has been implicated in the pathogenesis of obesity and related metabolic abnormalities. Studies on the association between serum uric acid (sUA) and metabolic syndrome (MetS) in juvenile obesity are scant. The effect of gender has not been evaluated.

METHODS

sUA (uricase method), anthropometric and biochemical indices were measured in gender-stratified children/adolescents consisting of 113 overweight/obese and 71 lean individuals.

RESULTS

In males, sUA was significantly elevated in overweight as well as obese patients. sUA was strongly associated with obesity indices and reflected sexual development, decreases in high density lipoprotein-cholesterol, and moderately, the number of MetS components. Waist circumference (WC) and Tanner stage explained 40% of sUA variability. Controlling for body mass index (BMI) and other MetS components, sUA was associated with abdominal obesity, explaining 30% of variability in WC. In females, sUA was significantly increased in obesity, high blood pressure (BP), and MetS and corresponded with the number of MetS components, indices of glucose metabolism, triglycerides (TG), and the atherogenecity index. Insulin-resistance (IR) (homeostasis model assessment; HOMA) and high BP explained 29% of sUA variability, whereas sUA, while controlling for BMI, age, and other MetS components, was associated with hypertriglyceridemia, hyperglycemia, high BP, and abdominal obesity. IR mediated the associations with high TG and glucose.

CONCLUSIONS

The association between sUA and MetS components in juvenile obesity is gender-specific, with females being related more closely and to more metabolic abnormalities. It may explain why, despite its lower concentrations, sUA is an independent predictor of mortality from all causes and from vascular diseases exclusively in females. Our findings may help in identifying metabolic abnormalities which may possibly be targeted by reducing sUA in males and females.

Age-related changes in plasma androgen levels and their association with cardiovascular risk factors in male Japanese office workers

AIM

To assess the age-related change in plasma androgen levels in healthy middle-aged men and whether any clinical parameters are associated with the hormonal change.

METHODS

The study was comprised of male Japanese office-workers aged 40-64 years, who had undergone an annual health check-up in 2002 and 2007 (96 and 76 men, respectively). Body mass index and blood pressure were measured, and serum concentration of lipids, glucose and uric acid in addition to plasma total testosterone, free testosterone and dehydroepiandrosterone sulfate (DHEA-S) levels were determined in the morning after an overnight fast. The 5-year hormonal changes and their associations with clinical parameters were analyzed in 33 men who repeated the examination at both check-ups. The cross-sectional associations of hormonal levels with clinical parameters were also investigated.

RESULTS

Age was negatively associated with free testosterone (r = -0.399, P < 0.001 in 2002; r = -0.458, P < 0.001 in 2007) and DHEA-S (r = -0.233, P = 0.02 in 2002; r = -0.336, P < 0.01 in 2007) but not with total testosterone, while the 5-year changes of free testosterone and DHEA-S levels were not significant and showed no associations with major cardiovascular risk factors. Cross-sectionally, after adjustment for age, linear regression analysis showed a positive association between free testosterone and blood hemoglobin and a negative association between total testosterone and serum uric acid.

CONCLUSION

In Japanese middle-aged men, 5-year androgen decline is too subtle to detect, and endogenous androgen levels seem to have relatively weak association with cardiovascular risk profiles.

Changes in waist circumference and body mass index in relation to changes in serum uric acid in Japanese individuals

OBJECTIVE

Studies have shown that obesity is associated with an increase in serum uric acid; and few data are available on the relationship between changes in measures of obesity and changes in uric acid concentrations. We investigated the relationship among percentage changes in waist circumference (%dWC), body mass index (%dBMI), and serum uric acid (%dUA).

METHODS

The data of 3153 individuals [1968 men, 1185 women (536 premenopausal, 649 postmenopausal)] who underwent general health screening over a 2-year period and were not taking antihyperuricemic medication were analyzed.

RESULTS

Stepwise multiple regression analysis showed that %dBMI was associated positively with %dUA in postmenopausal women and men, and the association retained statistical significance after adjustment for changes in blood pressure and in renal function. Association between %dBMI and %dUA was not significant in premenopausal women. In men, %dWC was a predicting factor for %dUA, although it did not remain significant when %dBMI was used as a covariate in the statistical model. Multivariate logistic regression analysis showed that the odds ratio of the association between the lowest %dBMI quartile (%dBMI < -1.86) and the lowest %dUA quartile (%dUA < -7.41) was 2.04 (95% CI 1.35-3.07) in postmenopausal women and 1.46 (95% CI 1.14-1.86) in men.

CONCLUSION

Weight loss may represent an effective nonmedical strategy for reducing serum UA levels, especially in postmenopausal women and men.

Gout in young migrant Filipino women in Israel: a changing epidemiology. Case reports and review of the literature

Gout is rare among young women. The prevalence of gout is increasing in the western world and the Far East, probably owing to life style changes. The association between hyperuricemia and gout, the metabolic syndrome and atherosclerosis is stronger in women. 40 years ago, the increased prevalence of hyperuricemia and gout in Filipino men living in the United States was described. Recently, Filipino men and women living in the western world were found to have increased risk of the metabolic syndrome and atherosclerosis. We describe two unusual cases of gout in premenopausal Filipino women living in Israel, both of which suffered from hypertension. We also describe the current knowledge about gout in women, in general, and in migrant Asian women, in particular, with an emphasis on its relations to the metabolic syndrome and atherosclerosis. The occurrence of gout in relatively young migrant Filipino women might signal a change in the epidemiology of this disease, and might signal that these women are more prone to develop the metabolic syndrome and its complications.