Iron Overload in Functional Hyperandrogenism: In a Randomized Trial, Bloodletting Does Not Improve Metabolic Outcomes

Polycystic ovary syndrome and iron overload: biochemical link and underlying mechanisms with potential novel therapeutic avenues

Polycystic ovary syndrome (PCOS) is an endocrine and metabolic disorder in women with components of significant genetic predisposition and possibly multiple, but not yet clearly defined, triggers. This disorder shares several clinical features with hemochromatosis, a genetically defined inheritable disorder of iron overload, which includes insulin resistance, increased adiposity, diabetes, fatty liver, infertility, and hyperandrogenism. A notable difference between the two disorders, however, is that the clinical symptoms in PCOS appear at much younger age whereas they become evident in hemochromatosis at a much later age. Nonetheless, noticeable accumulation of excess iron in the body is a common finding in both disorders even at adolescence. Hepcidin, the iron-regulatory hormone secreted by the liver, is reduced in both disorders and consequently increases intestinal iron absorption. Recent studies have shown that gut bacteria play a critical role in the control of iron absorption in the intestine. As dysbiosis is a common finding between PCOS and hemochromatosis, changes in bacterial composition in the gut may represent another cause for iron overload in both diseases via increased iron absorption. This raises the possibility that strategies to prevent accumulation of excess iron with iron chelators and/or probiotics may have therapeutic potential in the management of polycystic ovary syndrome.

The influence of ESR1 polymorphisms on selected hormonal, metabolic and mineral balance markers in women with hyperandrogenism

Hyperandrogenism is the most common endocrine disorder in women, characterized by an imbalance in normal estrogen and androgen levels in the blood. Androgens influence bone mineral density, body mass composition, muscle mass, mental state, and the regulation of sexual function.. The aim of the study was to assess the effect of estrogen receptor α gene (ESR1) polymorphisms on selected markers of bone metabolism and hormonal parameters in women with hyperandrogenism. The study group included 80 young women with hyperandrogenism who underwent measurements of bone mineral density (BMD), and determination of hormonal and metabolic parameters. Enzyme immunoassays were used to measure leptin, sRANKL (soluble receptor activator of nuclear factor-kB ligand), osteoprotegerin and 25-OH vitamin D total levels. An analysis of ESR1 gene polymorphisms was performed using the real-time PCR method. A relationship was demonstrated between the concentration of free estradiol (FEI) and the concentration of 17-OH-progesterone, and the ESR1 gene polymorphisms: rs3020314 (p = 0.031, p = 0.026 respectively) and rs1884051 (p = 0.033, p = 0.026 respectively). In conclusion, the ESR gene polymorphisms may be associated with hormonal disturbances in the concentration of estrogens and androgens, in hyperandrogenism in young women which may indirectly affect bone mineral density. However, no statistically significant relationships between the studied polymorphisms and the selected parameters of mineral metabolism have been demonstrated..

Association between Blood Donation and Malignant and Benign Tumour Risk: A Population-Based Study of 3.4 Million Participants in China

This study aims to identify the relationship between blood donation and malignant and benign tumour hospitalization risk. The cohort study was constructed in Shaanxi, China, to include blood donors and match nonblood donors one-to-one by gender, age, and county of residence. The study compared the hospitalization records of two groups from 2012 to 2018. A log-binomial regression model was used to estimate the relative risk (RR) of tumour risk between donors and nonblood donors among different age groups. A total of 1,625,599 donors were recruited (including 968,823 males) and compared with the matched nonblood donor group. Significantly lower risk of malignancy in males was found among donors (adjusted RR: 0.82, 95% CI: 0.75–0.92). Lower risks for specific types of tumours among donors were observed, including liver (0.42, [0.28–0.67]), lung (0.74, [0.59–0.87]), lymphoma (0.75, [0.62–0.85]), and oesophagus (0.55, [0.41–0.72]). However, the risk of brain cancer was higher among male donors (RR 1.19 [1.06–1.29]). Among female donors, lower risk of liver (0.57, [0.42–0.79]) and oesophagus malignancy (0.73, [0.62–0.88]) was observed. For benign tumours, male donors have a lower risk of benign skin tumour (0.79, [0.62–0.94]) and hemangioma and lymphangioma (0.75, [0.51–0.89]), while female donors have a lower risk in hemangioma and lymphangioma (0.65, [0.44–0.83]). We also found that the risk decreased with age among donors in the prevalence of tumours compared to that in nonblood donors ( $p<0.05$ ). Blood donation appears to be significantly associated with various tumour risks among both males and females. Overall, the risk of tumours decreased more substantially with age in blood donors compared with nonblood donors. Further research is warranted to investigate the impact of ‘health donor effects’ on these findings.

Effect of Iron Depletion by Bloodletting vs. Observation on Oxidative Stress Biomarkers of Women with Functional Hyperandrogenism Taking a Combined Oral Contraceptive: A Randomized Clinical Trial

Women with functional hyperandrogenism show both increased markers of oxidative stress and a mild iron overload. Combined oral contraceptives (COC) may worsen redox status in the general population. Since iron depletion ameliorates oxidative stress in other iron overload states, we aimed to address the changes in the redox status of these women as a consequence of COC therapy and of bloodletting, conducting a randomized, controlled, parallel, open-label clinical trial in 33 adult women with polycystic ovary syndrome or idiopathic hyperandrogenism. After three months of treatment with a COC, participants were randomized (1:1) to three scheduled bloodlettings or observation for another nine months. After taking a COC, participants showed a mild decrease in their plasma electrochemical antioxidant capacity, considering fast-acting antioxidants [MD: −1.51 (−2.43 to −0.60) μC, p = 0.002], and slow-acting antioxidants [MD: −1.90 (−2.66 to −1.14) μC, p < 0.001]. Women submitted to bloodletting showed a decrease in their non-enzymatic antioxidant capacity levels (NEAC) throughout the trial, whereas those individuals in the control arm showed a mild increase in these levels at the end of the study (Wilks’ λ: 0.802, F: 3.572, p = 0.041). Decreasing ferritin and plasma hemoglobin during the trial were associated with worse NEAC levels. COC may impair redox status in women with functional hyperandrogenism. Decreasing iron stores by scheduled bloodletting does not override this impairment.

Bloodletting has no effect on the blood pressure abnormalities of hyperandrogenic women taking oral contraceptives in a randomized clinical trial

Normoferritinemic women with functional hyperandrogenism show a mild iron overload. Iron excess, hyperandrogenism, and cardioautonomic dysfunction contribute to blood pressure (BP) abnormalities in these patients. Furthermore, combined oral contraceptives (COC) prescribed for hyperandrogenic symptoms may worse BP recordings. Iron depletion by phlebotomy appears to lower BP in other acquired iron overload conditions. We aimed to determine the effect of iron depletion on the office BP, ambulatory BP monitoring, and frequency of hypertension in patients with functional hyperandrogenism submitted to standard therapy with COC. We conducted a phase 2 randomized, controlled, parallel, open-label clinical trial (NCT02460445) in adult women with functional hyperandrogenism including hyperandrogenic polycystic ovary syndrome and idiopathic hyperandrogenism. After a 3-month run-in period of treatment with 35 µg ethinylestradiol plus 2 mg cyproterone acetate, participants were randomized (1:1) to three scheduled bloodlettings or observation for another 9 months. Main outcome measures were the changes in office BP, 24-h-ambulatory BP, and frequency of hypertension in both study arms. From June 2015 to June 2019, 33 women were included in the intention-to-treat analyses. We observed an increase in mean office systolic BP [mean of the differences (MD): 2.5 (0.3–4.8) mmHg] and night-time ambulatory systolic BP [MD 4.1 (1.4–6.8) mmHg] after 3 months on COC. The percentage of nocturnal BP non-dippers also increased, from 28.1 to 92.3% (P < 0.001). Office and ambulatory BP did not change throughout the experimental period of the trial, both when considering all women as a whole or as a function of the study arm. The frequency of the non-dipping pattern in BP decreased during the experimental period [OR 0.694 (0.577–0.835), P < 0.001], regardless of the study arm. Decreasing iron stores by scheduled bloodletting does not override the BP abnormalities caused by COC in women with functional hyperandrogenism.

Iron Reshapes the Gut Microbiome and Host Metabolism

Compelling studies have established that the gut microbiome is a modifier of metabolic health. Changes in the composition of the gut microbiome are influenced by genetics and the environment, including diet. Iron is a potential node of crosstalk between the host-microbe relationship and metabolic disease. Although iron is well characterized as a frequent traveling companion of metabolic disease, the role of iron is underappreciated because the mechanisms of iron's influence on host metabolism are poorly characterized. Both iron deficiency and excessive amounts leading to iron overload can have detrimental effects on cardiometabolic health. Optimal iron homeostasis is critical for regulation of host immunity and metabolism in addition to regulation of commensal and pathogenic enteric bacteria. In this article we review evidence to support the notion that altering composition of the gut microbiome may be an important route via which iron impacts cardiometabolic health. We discuss reshaping of the microbiome by iron, the physiological significance and the potential for therapeutic interventions.