The impact of obesity and insulin resistance on iron and red blood cell parameters: a single center, cross-sectional study

A farewell to phlebotomy-use of placenta-derived drugs Laennec and Porcine for improving hereditary hemochromatosis without phlebotomy: a case report

BACKGROUND

Human hepcidin, produced by hepatocytes, regulates intestinal iron absorption, iron recycling by macrophages, and iron release from hepatic storage. Recent studies indicate that hepcidin deficiency is the underlying cause of the most known form of hereditary hemochromatosis.

CASE PRESENTATION

A 44-year-old Asian man who developed type 2 diabetes mellitus had elevated serum ferritin levels (10,191 ng/mL). Liver biopsy revealed remarkable iron deposition in the hepatocytes and relatively advanced fibrosis (F3). Chromosomal analysis confirmed the presence of transferrin receptor type 2 mutations (c.1100T>G, c.2008_9delAC, hereditary hemochromatosis type 3 analyzed by Kawabata). The patient received intravenous infusions of Laennec (672 mg/day, three times/week) or oral administration with Porcine (3.87 g/day) for 84 months as an alternative to repeated phlebotomy. At the end of the treatment period, serum ferritin level decreased to 428.4 ng/mL (below the baseline level of 536.8 ng/mL). Hemoglobin A1c levels also improved after treatment with the same or lower dose of insulin (8.8% before versus 6.8% after). Plural liver biopsies revealed remarkable improvements in the grade of iron deposition and fibrosis (F3 before versus F1 after) of the liver tissue.

CONCLUSION

The discovery of hepcidin and its role in iron metabolism could lead to novel therapies for hereditary hemochromatosis. Laennec (parenteral) and Porcine (oral), which act as hepcidin inducers, actually improved iron overload in this hereditary hemochromatosis patient, without utilizing sequential phlebotomy. This suggests the possibility of not only improving the prognosis of hereditary hemochromatosis (types 1, 2, and 3) but also ameliorating complications, such as type 2 diabetes, liver fibrosis, and hypogonadism. Laennec and Porcine can completely replace continuous venesection in patients with venesection and may improve other iron-overloading disorders caused by hepcidin deficiency.

A test to measure oral iron absorption and glucose tolerance simultaneously in 18 to 55 year old premenopausal women

BACKGROUND & AIMS

Several methods are available to measure iron absorption (IA). The oral iron absorption test (OIAT) measures IA based on a change in serum iron (ΔSeFe) concentration after an oral iron dose. The objective of this study was to validate the OIAT by comparing it to the reference method of fractional iron absorption (FIA) using red blood cell incorporation of stable iron isotopes from a labeled iron dose. A second objective was to assess whether the OIAT could be done simultaneously with an oral glucose tolerance test (OGTT), since iron deficiency and glucose intolerance may coexist, especially among overweight individuals with low-grade inflammation.

METHODS

In this prospective experimental study, 116 women were enrolled and IA was measured using two different approaches 1) FIA from a labeled test meal containing 6 mg of ⁵⁷Fe and 2) the OIAT assessing ΔSeFe at 2 h after the intake of 100 mg oral iron, done simultaneously with an OGTT. Markers of iron status, glycaemia and inflammation, and serum hepcidin, were measured.

RESULTS

Prevalence of anemia and iron deficiency (defined as low serum ferritin) were 21% and 14%, respectively. ΔSeFe during the OIAT-OGTT was positively associated with FIA (r = 0.578, p < 0.001). ΔSeFe was not significantly correlated with markers of glucose and insulin metabolism during the OIAT-OGTT.

CONCLUSIONS

The combined OIAT and OGTT method described here correlates well with FIA measured by stable iron isotopes, and could provide information on both IA and glucose tolerance in a single 2-h test, decreasing the burden on patients. clinicaltrials.gov (NCT03642223).

Impact of admixture and ancestry on eQTL analysis and GWAS colocalization in GTEx

BACKGROUND

Population structure among study subjects may confound genetic association studies, and lack of proper correction can lead to spurious findings. The Genotype-Tissue Expression (GTEx) project largely contains individuals of European ancestry, but the v8 release also includes up to 15% of individuals of non-European ancestry. Assessing ancestry-based adjustments in GTEx improves portability of this research across populations and further characterizes the impact of population structure on GWAS colocalization.

RESULTS

Here, we identify a subset of 117 individuals in GTEx (v8) with a high degree of population admixture and estimate genome-wide local ancestry. We perform genome-wide cis-eQTL mapping using admixed samples in seven tissues, adjusted by either global or local ancestry. Consistent with previous work, we observe improved power with local ancestry adjustment. At loci where the two adjustments produce different lead variants, we observe 31 loci (0.02%) where a significant colocalization is called only with one eQTL ancestry adjustment method. Notably, both adjustments produce similar numbers of significant colocalizations within each of two different colocalization methods, COLOC and FINEMAP. Finally, we identify a small subset of eQTL-associated variants highly correlated with local ancestry, providing a resource to enhance functional follow-up.

CONCLUSIONS

We provide a local ancestry map for admixed individuals in the GTEx v8 release and describe the impact of ancestry and admixture on gene expression, eQTLs, and GWAS colocalization. While the majority of the results are concordant between local and global ancestry-based adjustments, we identify distinct advantages and disadvantages to each approach.

Status Besi dan Kualitas Diet pada Wanita Usia Subur Pranikah Obesitas di Kota Semarang

Background: Women of reproductive age are potentially to have double-burden malnutrition due to poor diet quality. Obesity-related anemia affects iron homeostasis (hypoferremia) through low-grade inflammation.Objectives: This study aimed to analyze the differences of iron status among women of reproductive age based on obesity status and diet quality based on iron and obesity status.Methods: A cross-sectional study of female students, aged 18-22 years old that classified as obese (n=25) and non-obese (n=25). Subjects were selected by proportional random sampling. This study used iron status and diet quality as variable datas. Blood samples were taken to determined iron status (Fe serum). Diet quality was analyzed by SQ-FFQ and DQI-I. Statistical analysis using Independent-T Test, One-way ANOVA, Kruskal Wallis, Mann Whitney tests.Results: There were 20% of obese subjects had low iron status and majority (94%) had low diet quality score (52.04±5.2). Iron status of obese women (83.9±20.7 µg/dl) significantly differed to non-obese women (99.2±26.1 µg/dl), p=0.027. Obese group with low iron status had lower diet quality and moderation component score, however adequacy score was higher than other groups, p<0.05. There were no significant differences in variation and overall balance among all groups, p>0.05.Conclusions: Iron status of obese women was significantly different than non-obese women. Obese group with low iron status had lower diet quality and moderation component score, however adequacy score was higher than other groupsABSTRAKLatar Belakang: Wanita Usia Subur (WUS) rentan terkena masalah gizi ganda akibat kualitas diet yang buruk. Obesitas terkait anemia disebabkan inflamasi tingkat rendah yang mempengaruhi homeostasis zat besi (hipoferrimia). Tujuan: Penelitian ini bertujuan untuk menganalisis perbedaan status besi WUS berdasarkan status obesitas, dan perbedaan kualitas diet berdasarkan status besi dan obesitas. Metode: Penelitian ini menggunakan desain cross-sectional, dengan subjek mahasiswi berjumlah 25 orang obesitas dan 25 orang non-obesitas, dipilih menggunakan teknik proportional random sampling. Data yang diambil berupa status besi (kadar Fe serum) melalui pengambilan sampel darah, dan kualitas diet menggunakan wawancara SQ-FFQ dan analisis DQI-I. Analisis menggunakan uji Independent-T Test, One-way ANOVA, Kruskal Wallis, dan Mann Whitney.Hasil: Sebanyak 20% WUS obesitas memiliki status besi rendah dan mayoritas subjek (94%) memiliki kualitas diet rendah (52,04±5,2). Status besi WUS obesitas (83,9±20,7µg/dl) berbeda signifikan dibandingkan WUS non-obesitas (99,2±26,1µg/dl), p=0,027. Kelompok WUS obesitas dengan status besi rendah memiliki skor kualitas diet dan komponen moderasi lebih rendah, namun memiliki skor kecukupan lebih tinggi dibandingkan kelompok lainnya, p<0,05. Komponen variasi dan keseimbangan keseluruhan pada semua kelompok tidak menunjukkan perbedaan signifikan, p>0,05.Kesimpulan: Status besi WUS obesitas signifikan lebih rendah dibandingkan WUS non-obesitas. Kelompok WUS obesitas dengan status besi rendah memiliki skor kualitas diet dan moderasi lebih rendah, namun memiliki skor kecukupan lebih tinggi dibandingkan kelompok lainnya. 

Obesity and iron-deficiency anemia in women of reproductive age in northern Iran

BACKGROUND

Obesity and iron deficiency (ID) are two forms of the most usual nutritional disorders worldwide. Some studies have discovered a correlation between ID and obesity although more investigation is required. This study was aimed to determine the association between obesity and ID anemia (IDA) in Iranian childbearing age women.

MATERIALS AND METHODS

This cross-sectional study was done on 256 women of reproductive age in northern Iran. The anthropometric measurements including height and weight were measured, and body mass index (BMI) was calculated. Low blood index of the hemoglobin (Hb), mean cell volume (MCV), and mean corpuscular hemoglobin (MCH) were evaluated with ferritin, serum iron, and total iron-binding capacity. Baseline data were expressed as means ± standard deviations. Chi-square test was applied to compare the categorical variable. Differences between the two groups were evaluated with independent samples t-test. A value of P < 0.05 was considered as statistically significant.

RESULTS

Obesity was in urban women higher than rural women (55.1% vs. 44.9%), and this difference was significant (P < 0.021). There was found no association between hematological characteristics and BMI. The data showed that only 13.4% of obese women and 17.1% of the women with normal weight had IDA (odds ratio = 0.75; 95% confidence interval: 0.39-1.49, P > 0.05).

CONCLUSIONS

According to the results of this study, it seems that the relationship between obesity and IDA is controversial. Hence, further studies are needed to be done.

Obesity-related known and candidate SNP markers can significantly change affinity of TATA-binding protein for human gene promoters

BACKGROUND

Obesity affects quality of life and life expectancy and is associated with cardiovascular disorders, cancer, diabetes, reproductive disorders in women, prostate diseases in men, and congenital anomalies in children. The use of single nucleotide polymorphism (SNP) markers of diseases and drug responses (i.e., significant differences of personal genomes of patients from the reference human genome) can help physicians to improve treatment. Clinical research can validate SNP markers via genotyping of patients and demonstration that SNP alleles are significantly more frequent in patients than in healthy people. The search for biomedical SNP markers of interest can be accelerated by computer-based analysis of hundreds of millions of SNPs in the 1000 Genomes project because of selection of the most meaningful candidate SNP markers and elimination of neutral SNPs.

RESULTS

We cross-validated the output of two computer-based methods: DNA sequence analysis using Web service SNP_TATA_Comparator and keyword search for articles on comorbidities of obesity. Near the sites binding to TATA-binding protein (TBP) in human gene promoters, we found 22 obesity-related candidate SNP markers, including rs10895068 (male breast cancer in obesity); rs35036378 (reduced risk of obesity after ovariectomy); rs201739205 (reduced risk of obesity-related cancers due to weight loss by diet/exercise in obese postmenopausal women); rs183433761 (obesity resistance during a high-fat diet); rs367732974 and rs549591993 (both: cardiovascular complications in obese patients with type 2 diabetes mellitus); rs200487063 and rs34104384 (both: obesity-caused hypertension); rs35518301, rs72661131, and rs562962093 (all: obesity); and rs397509430, rs33980857, rs34598529, rs33931746, rs33981098, rs34500389, rs63750953, rs281864525, rs35518301, and rs34166473 (all: chronic inflammation in comorbidities of obesity). Using an electrophoretic mobility shift assay under nonequilibrium conditions, we empirically validated the statistical significance (α < 0.00025) of the differences in TBP affinity values between the minor and ancestral alleles of 4 out of the 22 SNPs: rs200487063, rs201381696, rs34104384, and rs183433761. We also measured half-life (t1/2), Gibbs free energy change (ΔG), and the association and dissociation rate constants, ka and kd, of the TBP-DNA complex for these SNPs.

CONCLUSIONS

Validation of the 22 candidate SNP markers by proper clinical protocols appears to have a strong rationale and may advance postgenomic predictive preventive personalized medicine.

Obesity and iron deficiency: a quantitative meta-analysis

Hypoferraemia (i.e. iron deficiency) was initially reported among obese individuals several decades ago; however, whether obesity and iron deficiency are correlated remains unclear. Here, we evaluated the putative association between obesity and iron deficiency by assessing the concentration of haematological iron markers and the risks associated with iron deficiency in both obese (including overweight) subjects and non-overweight participants. We performed a systematic search in the databases PubMed and Embase for relevant research articles published through December 2014. A total of 26 cross-sectional and case-control studies were analysed, comprising 13,393 overweight/obese individuals and 26,621 non-overweight participants. Weighted or standardized mean differences of blood iron markers and odds ratio (OR) of iron deficiency were compared between the overweight/obese participants and the non-overweight participants using a random-effects model. Compared with the non-overweight participants, the overweight/obese participants had lower serum iron concentrations (weighted mean difference [WMD]: -8.37 μg dL(-1) ; 95% confidence interval [CI]: -11.38 to -5.36 μg dL(-1) ) and lower transferrin saturation percentages (WMD: 2.34%, 95% CI: -3.29% to -1.40%). Consistent with this finding, the overweight/obese participants had a significantly increased risk of iron deficiency (OR: 1.31; 95% CI: 1.01-1.68). Moreover, subgroup analyses revealed that the method used to diagnose iron deficiency can have a critical effect on the results of the association test; specifically, we found a significant correlation between iron deficiency and obesity in studies without a ferritin-based diagnosis, but not in studies that used a ferritin-based diagnosis. Based upon these findings, we concluded that obesity is significantly associated with iron deficiency, and we recommend early monitoring and treatment of iron deficiency in overweight and obese individuals. Future longitudinal studies will help to test whether causal relationship exists between obesity and iron deficiency.