Plasma ferritin concentration is positively associated with in vivo fatty acid mobilization and insulin resistance in obese women

A New Concept in Antidiabetic Therapeutics: A Concerted Removal of Labile Iron and Intracellular Deposition of Zinc

BACKGRUOUND

The inflammatory process is known to be an integral part of the pathophysiology of type 2 diabetes mellitus (T2DM). The "labile," redox-active iron, serving as a catalyst in Fenton reaction, producing the deleterious reactive oxygen species, triggering and maintaining inflammation, is hypothesized to play a causative role in this process. Concenter Biopharma continued the development of a new platform of iron chelators (Zygosids), first initiated at the Hebrew University of Jerusalem, Israel (HUJI), acting via the novel mechanism, based on a sequestration of the labile redox-active iron and its substitution by zinc or gallium. The mode of action of Zygosids is based on the higher affinity of the metal-binding moiety of the complex to Fe3+ in comparison to already bound ion, leading to rapid release of the ion of another metal and chelation of Fe3+. Concomitantly, zinc ion, released by the complex, is known for its antidiabetic and anti-inflammatory role.

METHODS

The therapeutic effect of zinc-desferrioxamine (Zygosid-50) and gallium-desferrioxamine, was tested on fat sand rat (Psammomys obesus) model of diet-induced T2DM and on Leprdb transgenic diabetic mice.

RESULTS

Zygosids demonstrated an ability to noticeably reduce blood glucose and insulin levels and improve the lipid profile. Moreover, an ability to mitigate insulin resistance by >90% was shown on the sand rat model. In addition, a potent anti-inflammatory effect, expressed as a diminishment of the proinflammatory cytokines in tissue levels, was demonstrated.

CONCLUSION

Zygosids demonstrated robust therapeutic efficacy in treatment of T2DM. Importantly, no adverse effects were detected, in all the experiments, indicating high safety profile.

Adipose triglyceride lipase mediates lipolysis and lipid mobilization in response to iron-mediated negative energy balance

Maintenance of energy balance is essential for overall organismal health. Mammals have evolved complex regulatory mechanisms that control energy intake and expenditure. Traditionally, studies have focused on understanding the role of macronutrient physiology in energy balance. In the present study, we examined the role of the essential micronutrient iron in regulating energy balance. We found that a short course of dietary iron caused a negative energy balance resulting in a severe whole body wasting phenotype. This disruption in energy balance was because of impaired intestinal nutrient absorption. In response to dietary iron-induced negative energy balance, adipose triglyceride lipase (ATGL) was necessary for wasting of subcutaneous white adipose tissue and lipid mobilization. Fat-specific ATGL deficiency protected mice from fat wasting, but caused a severe cachectic response in mice when fed iron. Our work reveals a mechanism for micronutrient control of lipolysis that is necessary for regulating mammalian energy balance.

Association Between Serum Ferritin Concentration and Risk of Adverse Maternal and Fetal Pregnancy Outcomes: A Retrospective Cohort Study

OBJECTIVE

This study evaluated the associations of serum ferritin (SF) concentration during pregnancy with the risk of adverse maternal and fetal pregnancy outcomes.

METHODS

We conducted a retrospective study of 2327 pregnant women from 2015 to 2020 in Guangdong, China. SF concentrations were measured at 16-18th and 28-32th week of gestation. Logistic regression models were applied to estimate the association between SF concentration and the risk of adverse pregnancy outcomes.

RESULTS

After multivariable adjustment, the odds ratio (OR) of the highest quartile of SF concentration at 16-18th week of gestation was 1.43 (95% confidence interval [CI]: 1.09, 1.89) for gestational diabetes mellitus (GDM) and 1.79 (95% CI: 1.15, 2.79) for small for gestational age (SGA) when compared with the lowest quartile. At 28-32th week of gestation compared with the lowest quartile, women with SF in the highest quartile had an increased risk of SGA (OR: 1.62; 95% CI: 1.01, 2.62). Moreover, the lowest quartile of SF concentration decreased risk of SGA by 90% (95% CI: 0.01, 0.80) when compared with the highest quartile among pregnancy women with GDM.

CONCLUSION

Elevated SF concentrations increased the risk of GDM and SGA during pregnancy. Maintaining an appropriately low level of maternal SF at 28-32th week of gestation in women with GDM could reduce the risk of SGA.

Improvement in Muscle Strength and Metabolic Parameters Despite Muscle Mass Loss in the Initial Six Months After Bariatric Surgery

BACKGROUND

An aggravation in pre-existing sarcopenia or the onset of sarcopenia may occur in the scenario of extensive and fast weight loss in the initial months following bariatric surgery. The accurate identification of sarcopenia criteria and its metabolic repercussions is vital for its correct management. The aim of this study is to evaluate the correlation between the diagnosis criteria for sarcopenia and metabolic repercussions during the first 6 months following bariatric surgery.

METHODS

A prospective single-center cohort study was conducted. Convenience sampling was performed among patients with severe obesity undergoing preoperative evaluation for bariatric surgery. Metabolic parameters, nutritional evaluation, and skeletal muscle evaluation were assessed before surgery and 6 months later.

RESULTS

A total of 129 patients were selected, 62 participants were included in the final analysis. Mean age was 37.7 years and 88.4% of participants were women. Mean body mass index was 41.8 kg/m2 and 47.8% of patients were sedentary. Sleeve gastrectomy was performed in 41 patients and Roux-en-Y gastric bypass in 21 patients. Significant improvement regarding muscle strength and function after surgery was observed. Sarcopenia criteria were not met by any participant before and after surgery. Blood glucose and ferritin levels remained independently associated with change in muscle strength.

CONCLUSIONS

Functional evaluation methods did not reflect the reduction in skeletal muscle mass demonstrated in bioelectrical impedance analysis 6 months after bariatric surgery in comparison to the preoperative baseline. Improvement in muscle strength was followed by improvement in metabolic parameters.

Plasma Phospholipids with Long-Chain Polyunsaturated Fatty Acids and Dihydroceramides at the Crossroads of Iron Stores and Insulin Resistance

SCOPE

Iron plays an important role in the pathogenesis of insulin resistance (IR) and type 2 diabetes. Recent studies suggest a role of specific lipids in the induction of IR, but the potential relationships between iron and lipid metabolites in relation to IR have not been explored. Therefore, the aim of the study is to evaluate the association among iron, IR, and the lipidome.

METHODS AND RESULTS

The plasma lipidome, IR, parameters of iron metabolism, and several cytokines and adipokines in 65 overweight/obese participants are measured. Measurements of IR correlate positively with ferritin, a measure of iron storage (r = 0.35, p = 0.005), and negatively with adiponectin (r = -0.30, p = 0.02). The serum ferritin/adiponectin ratio has a stronger association with IR (r = 0.41, p < 0.001). From multivariate analyses adjusted for age, sex, and BMI, several phospholipids containing long chain polyunsaturated fatty acids (PUFA) with 20-22 carbons (phosphatidylcholines, phosphatidylethanolamines, phosphatidylinositols, and a phosphatidylserine), are positively associated with ferritin and the ferritin/adiponectin ratio. Two dihydroceramides (Cer(18:0/22:0), Cer(18:0/24:0)) and several diglycerides and triglycerides, mainly comprised of C14:0, C16:0, C18:0, C18:1, and C18:2, also have positive correlations with ferritin and the ferritin/adiponectin ratio.

CONCLUSIONS

The positive associations between these lipid species and ferritin or the ferritin/adiponectin ratio suggest a potential crosstalk between iron and lipid metabolism in obesity and IR.

Possible dysmetabolic hyperferritinemia in hyperinsulinemic horses

Background

Hyperinsulinemia associated with equine metabolic syndrome and pituitary pars intermedia dysfunction is a risk factor for laminitis. Research in other species has shown elevated body iron levels as both a predictor and consequence of insulin resistance. In humans, this is known as dysmetabolic hyperferritinemia.

Aim

To explore the relationship between equine hyperinsulinemia and body iron levels.

Methods

We reviewed case histories and laboratory results from an open access database maintained by the Equine Cushing's and Insulin Resistance Group Inc. (ECIR). We identified 33 horses with confirmed hyperinsulinemia and laboratory results for serum iron, total iron binding capacity, and ferritin. Pearson correlation was used to test the relationship between insulin and iron indices. Additionally, we performed a secondary analysis of a previously reported controlled trial that was originally designed to test the correlation between iron status and the insulin response in horses. Here, we used a t-test to compare the mean values of insulin and ferritin between horses we categorized as normal or hyperinsulinemic based on their response to an oral challenge.

Results

Serum ferritin exceeded published reference range in 100% of the horses identified from the ECIR database. There were no statistically significant associations between insulin indices (RISQI, log insulin) and iron indices (log serum iron, log TSI%, log ferritin). There were trends for a negative association between RISQI and log iron [r(31) = -0.33, p = 0.058] and a positive association between age and ferritin [r(30) = 0.34, p = 0.054]. From the secondary data analysis of published data, we found significantly elevated ferritin (p = 0.05) in horses considered hyperinsulinemic by dynamic insulin testing compared to horses with a normal response.

Conclusion

These results suggest the potential for iron overload in hyperinsulinemic horses, a feature documented in other species and should stimulate further study into the relationship between insulin and iron dysregulation in the horse.

Association between Serum Ferritin and Blood Lipids: Influence of Diabetes and hs-CRP Levels

This study is aimed at exploring the relationship between serum ferritin and blood lipids and the influence of diabetes and different hs-CRP levels. A total of 8163 subjects were analyzed. Participators were classified according to serum ferritin, diabetes, and two hs-CRP levels. Blood lipids were determined using standardized methods and conditions. Except for HDL-C, there was a significant increase in blood lipids in the progressive ferritin group with normal hs-CRP levels (P < 0.05). But HDL-C was just the opposite (P < 0.0001). In nondiabetic patients, TG, TC, and LDL-C were significantly elevated in the progressive ferritin group (P < 0.05). And, HDL-C was just the opposite (P < 0.05). The generalized linear model and the parsimonious model showed that serum TG was positively correlated with ferritin, and LDL-C was negatively correlated with ferritin (P < 0.05). But the correlation between LDL-C and ferritin was broken (P > 0.05). After a sufficient adjustment, there was a positive correlation between serum TG and ferritin and a negative correlation between LDL-C and ferritin. Nonetheless, a negative correlation between LDL-C and ferritin is influenced by diabetes frailly. And, there was no change of relationship between lipids and ferritin in different hs-CRP levels. We found a real relationship between ferritin and lipids after sufficient adjustment for confounders.

The Association Between Serum Ferritin Concentration and Visceral Adiposity Estimated by Whole-Body DXA Scan in Women With Polycystic Ovary Syndrome

Objective: Women with polycystic ovary syndrome (PCOS) are characterized by insulin resistance and higher prevalence of obesity. Serum ferritin is increased in obesity and is associated with insulin resistance. The aim of the present study was to evaluate the relationships between serum ferritin concentration with insulin resistance and body composition estimated by dual-energy X-ray absorptiometry (DXA) in PCOS women in comparison to the control group. Patients and Methods: One hundred four women were enrolled to the study-65 women with PCOS and 39 women matched for age and BMI as a control group. Serum ferritin concentration and oral glucose tolerance test (OGTT) were performed. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. DXA was performed to estimate fat, fat-free mass, and visceral adipose tissue (VAT). Results: Women with PCOS have higher serum concentration of ferritin (p = 0.002), insulin at baseline (p = 0.03), at 60 min of OGTT (p = 0.01), at 120 min of OGTT (p = 0.004), HOMA-IR (p = 0.03), and VAT (p = 0.0001) in comparison to the control group. We observed a relationship of serum ferritin with insulin concentration at baseline (r = 0.25, p = 0.04) and at 120 min of OGTT (r = 0.31, p = 0.01) and with HOMA-IR (r = 0.30, p = 0.01) in the PCOS group. We noticed an association between serum ferritin concentration and VAT (r = 0.42, p = 0.001), trunk fat mass (r = 0.25, p = 0.04), and android fat mass (r = 0.25, p = 0.04) in the PCOS group. Multiple regression analysis revealed that ferritin (p = 0.02, β = 0.17), insulin at baseline (p = 0.001, β = 0.30), glucose at the 120 min of OGTT (p = 0.007, β = 0.26), and triglycerides (p = 0.001, β = 0.33) were independent predictors of VAT amount in PCOS women. Conclusions: Elevated serum ferritin concentration is connected with insulin resistance as well as with DXA-estimated VAT, android, and trunk fat mass in PCOS women, and could be a marker of metabolic dysfunction.

Iron Metabolism in Cancer

Demanded as an essential trace element that supports cell growth and basic functions, iron can be harmful and cancerogenic though. By exchanging between its different oxidized forms, iron overload induces free radical formation, lipid peroxidation, DNA, and protein damages, leading to carcinogenesis or ferroptosis. Iron also plays profound roles in modulating tumor microenvironment and metastasis, maintaining genomic stability and controlling epigenetics. in order to meet the high requirement of iron, neoplastic cells have remodeled iron metabolism pathways, including acquisition, storage, and efflux, which makes manipulating iron homeostasis a considerable approach for cancer therapy. Several iron chelators and iron oxide nanoparticles (IONPs) has recently been developed for cancer intervention and presented considerable effects. This review summarizes some latest findings about iron metabolism function and regulation mechanism in cancer and the application of iron chelators and IONPs in cancer diagnosis and therapy.