Iron overload in Sub-Saharan Africa: to what extent is it a public health problem?

Revealing the contribution of iron overload-brown adipocytes to iron overload cardiomyopathy: Insights from RNA-seq and exosomes coculture technology

Iron overload has been demonstrated to be associated with insulin resistance, iron overload cardiomyopathy (IOC). Brown adipose tissue (BAT) is emerging as a novel therapeutic target for the treatment of various diseases, not only because of its capacity for dissipating excess energy via non-shivering thermogenesis, but also because of its implication in physiological and pathophysiological processes. However, little attention has been devoted to the precise alterations and impacts of iron overload-BAT. We conducted RNA-Seq analysis on BAT samples obtained from mice subjected to a high iron diet (HID) or a normal chow diet (CON), respectively. The RNA-seq transcriptomic analysis revealed that 1,289 differentially expressed RNAs (DEGs) were identified, with a higher number of the downregulated genes (910 genes) compared to the upregulated genes (379 genes). The results of Gene Ontology (GO) and The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that the downregulated DEGs were primarily involved in hypertrophic cardiomyopathy, dilated cardiomyopathy, which were defined as IOC under the iron overload condition. The association between iron overload-BAT with cardiomyopathy was further investigated using exosome coculture technology. Our results demonstrated that the exosomes derived from ferric citrate treated-mature HIB 1B brown adipocytes, could be internalized by HL-1 cardiomyocytes, and contributed to the dysfunction in these cells. The present study has revealed the alterations and impacts of iron overload-BAT, particularly on the onset of IOC via not only RNA-seq but also exosomes coculture technology. The outputs might shed light on the novel therapeutic strategies for the treatment of IOC.

Iron-fortified water: a new approach for reducing iron deficiency anemia in resource-constrained settings

A new approach for fortification of drinking water is presented for combating iron deficiency anemia (IDA) worldwide. The idea is to leach Fe from a bed containing granular metallic iron (Fe0), primarily using ascorbic acid (AA). AA forms very stable and bioavailable complexes with ferrous iron (FeII). Calculated amounts of the FeII-AA solution can be added daily to the drinking water of households or day-care centers for children and adults (e.g. hospitals, kindergartens/schools, refugee camps) to cover the Fe needs of the populations. Granular Fe0 (e.g., sponge iron) in filters is regarded as a locally available Fe carrier in low-income settings, and, AA is also considered to be affordable in low-income countries. The primary idea of this concept is to stabilize FeII from the Fe0 filter by using an appropriate AA solution. An experiment showed that up to 12 mg Fe can be daily leached from 1.0 g of a commercial sponge iron using a 2 mM AA solution. Fe fortification of safe drinking water is a practicable, affordable and efficient method for reducing IDA in low-income communities.

Iron-containing cookware for the reduction of iron deficiency anemia among children and females of reproductive age in low- and middle-income countries: A systematic review

Background & objective

There is limited evidence regarding the efficacy of iron-containing pots and ingots in reducing iron deficiency (ID) and iron deficiency anemia (IDA) in low- and middle-income countries (LMICs). The objective of this systematic review is to summarize the evidence regarding the effect of iron-containing cookware on ID and IDA among children and females of reproductive age (FRA) in LMICs.

Methods

Searches were last conducted in May 2019 in PubMed, Embase, Cochrane Library, Web of Science, Scopus, CAB Abstracts, POPLINE, LILACS, ProQuest Dissertations & Theses Global, WHO ICTRP and ClinicalTrials.gov. Hand searching was also conducted. Selection criteria included randomized-controlled trials (RCTs), quasi-experimental studies and observational studies with control groups that studied the effect of iron-containing cookware in children (4 months-11 years) and females of reproductive age (12–51 years).

Results

Eleven studies were eligible for inclusion in the review. Statistically significant increases in hemoglobin and/or iron indices (p < 0.05) were observed in 50% (4/8) of studies on pots (relative change/mean difference in Hb: -0.4–1.20 g/dL), and 33.3% (1/3) of studies on ingots (relative change/mean difference in Hb: 0.32–1.18 g/dL). Positive outcomes (p < 0.05) were observed among children in 50% (4/8) of studies and among FRA in 28.6% (2/7) of studies. Compliance ranged from 26.7–71.4% daily use of pots to 90–93.9% daily use of ingots.

Conclusions

There are indications that, with reasonable compliance, iron-containing cookware could serve as a means of reducing IDA, especially among children. The potential advantages of iron-containing cookware include relative cost-effectiveness and complementary combination with other interventions. However, further research is needed regarding both the efficacy and safety of this intervention.

A systematic review of the epidemiology of unrecorded alcohol consumption and the chemical composition of unrecorded alcohol

BACKGROUND AND AIMS

Unrecorded alcohol constitutes about 30% of all alcohol consumed globally. The aims of this systematic review were to determine the epidemiology (occurrence, types, prevalence) of unrecorded alcohol consumption in different countries/regions, analyse the chemical composition of unrecorded alcohol and examine health outcomes caused by the consumption of unrecorded alcohol, based on either epidemiology or toxicology.

METHODS

A systematic search for, and qualitative analysis of, papers with empirical results on the different categories of unrecorded alcohol, based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Unrecorded alcohol was widespread in all regions of the world. Artisanal fermented beverages and spirits were the most common categories of unrecorded alcohol globally, and were available on all continents. In India, industrially produced spirits (country spirits) were most prevalent. In Russia and countries of the former Soviet Union, surrogate alcohols complemented artisanal spirits. Cross-border shopping was the most prevalent method of obtaining unrecorded alcohol in parts of Europe. Ethanol was the most harmful ingredient of unrecorded alcohol, and health consequences due to other ingredients found in unrecorded alcohol were scarce. However, as unrecorded alcohol is usually the least expensive form of alcohol available in many countries, it may contribute to higher rates of chronic and irregular heavy drinking.

CONCLUSIONS

Very large amounts of alcohol are produced globally that go unrecorded. The primary harm from this kind of alcohol arises from the fact that it is typically much cheaper than licit alcohol.

Intake of alcoholic beverages is a predictor of iron status and hemoglobin in adult Tanzanians

Iron deficiency is widespread in sub-Saharan Africa, but its predictors are not fully understood. We conducted a cross-sectional study among adults around Lake Victoria to describe iron status and asses the role of dietary and infectious predictors. Linear regression analyses were used to assess the role of infections and intake of meat, fish, fruit/vegetables, alcoholic beverages, and soil on hemoglobin and serum ferritin, while controlling for elevated serum alpha(1)-antichymotrypsin (ACT). Among 1498 participants, the mean age was 33.3 (14-87) y with 53.9% females. More than one-half ate fish daily, 6% ate fruit/vegetables daily, and only 11% ate meat weekly. One-third consumed alcoholic beverages and one-fifth of females consumed soil. Hookworm (80.3%), Schistosoma mansoni (64.7%), and HIV (7.3%) infection were common. Anemia was found in 48.2% of females (<120 g/L hemoglobin) and 40.1% of males (<130 g/L hemoglobin), and 22.3% of females and 7.0% of males had depleted iron stores (serum ferritin <12 microg/L). In multivariate analyses, alcoholic beverage consumption and HIV were positive, whereas soil eating and hookworm infection were negative predictors of serum ferritin. Alcoholic beverage consumption was a positive predictor of hemoglobin, and soil eating, HIV, and hookworm infection were negative predictors. Intakes of meat, fish, and fruit or vegetables were not predictors. Elevated serum ACT was a predictor of both hemoglobin and serum ferritin. Anemia and depleted iron stores were common, whereas iron overload was rare. In conclusion, the associations between alcoholic beverage intake and hemoglobin and iron status suggest that alcoholic beverages may contain micronutrients essential to erythropoiesis. The role of alcoholic beverage intake and other determinants of hemoglobin and iron status in low-income populations needs to be better elucidated.

Diabetes and the risk of tuberculosis: a neglected threat to public health?

OBJECTIVES

Tuberculosis (TB) remains a major global public health problem. In the past, a relationship between TB and diabetes mellitus (DM) was recognized, and its importance was acknowledged through joint treatment clinics. However, this is rarely highlighted in current research or control priorities. This paper aims to evaluate the evidence for an association between these two diseases.

METHODS

A Medline literature search was undertaken, supplemented by checking references and contacting experts. We critically appraised studies that quantified the association between TB and DM, and were published after 1995. We assessed study quality according to criteria such as sample size, method of selection of cases and controls, losses to follow-up, quality and method of control of confounding, and summarized the results narratively and in tabular form.

RESULTS

All studies identified statistically significant and clinically important associations, with the increase in risk or odds of TB varying between 1.5- and 7.8-fold for those with DM. Risk was highest at younger ages. Most studies had not measured and controlled adequately for potential major confounders.

DISCUSSION

There is strong evidence for an association between TB and DM, which has potential public health implications. Further well-designed studies are needed to assess the magnitude precisely.

Hemochromatosis and alcoholic liver disease

The close association of excessive alcohol consumption and clinical expression of hemochromatosis has been of widespread interest for many years. In most populations of northern European extraction, more than 90% of patients with overt hemochromatosis are homozygous for the C282Y mutation in the HFE gene. Nevertheless, the strong association of heavy alcohol intake with the clinical expression of hemochromatosis remains. We (individually or in association with colleagues from our laboratories) have performed three relevant studies in which this association was explored. In the first, performed in 1975 before the cloning of the HFE gene, the frequency of clinical symptoms and signs was compared in patients with classical hemochromatosis who consumed 100 g or more of alcohol per day versus in nondrinkers or moderate drinkers who consumed less than 100 g of alcohol per day. The results showed no difference between the two groups except for features of complications of alcoholism in the first group, especially jaundice, peripheral neuritis, and hepatic failure. Twenty-five percent of those with heavy alcohol consumption showed histologic features of alcoholic liver disease (including cirrhosis) together with heavy iron overload. It was concluded that these patients had the genetic disease complicated by alcoholic liver disease. In the second study (2002), 206 subjects with classical HFE-associated hemochromatosis in whom liver biopsy had been performed were evaluated to quantify the contribution of excess alcohol consumption to the development of cirrhosis in hemochromatosis. Cirrhosis was approximately nine times more likely to develop in subjects with hemochromatosis who consumed more than 60 g of alcohol per day than in those who drank less than this amount. In the third study (2002), 371 C282Y-homozygous relatives of patients with HFE-associated hemochromatosis were assessed. Eleven subjects had cirrhosis on liver biopsy and four of these drank 60 g or more of alcohol per day. The reason why heavy alcohol consumption accentuates the clinical expression of hemochromatosis is unclear. Increased dietary iron or increased iron absorption is unlikely. The most likely explanation would seem to be the added co-factor effect of iron and alcohol, both of which cause oxidative stress, hepatic stellate cell activation, and hepatic fibrogenesis. In addition, the cumulative effects of other forms of liver injury may result when iron and alcohol are present concurrently. Clearly, the addition of dietary iron in subjects homozygous for hemochromatosis would be unwise.

Iron-induced oxidative damage in colon carcinoma (Caco-2) cells

Intestinal epithelial cells have an active apical iron uptake system that is involved in the regulated absorption of iron. By the action of this system, intestinal cells acquire increasing amounts of iron with time. Since intracellular reactive iron is a source of free radicals and a possible cause of colon carcinoma, this study analyzed the oxidative damages generated by iron accumulation in Caco-2 cells. Cells cultured with increasing concentrations of iron increased both total intracellular iron and the reactive iron pool, despite an active IRE/IRP system, which regulates intracellular iron levels. Increasing concentrations of iron resulted in increased protein oxidative damage, as shown by the immunoreactivity for 4-hydroxy-2-nonenal-modified proteins, and markedly induced DNA oxidation determined by 8-hydroxy-2'-deoxyguanidine production. Iron also impaired cell viability, resulting in increased cell death after 6 days of culture. In summary, iron accumulation by intestinal Caco-2 cells correlated with oxidative damage to proteins and DNA. Oxidative damage finally resulted in loss of cell viability. The Fe-induced oxidative damage observed may be relevant in understanding the cascade of events associated with iron-mediated colon carcinogenesis.