Zinc and selenium levels in women with gestational diabetes mellitus at Medani Hospital, Sudan

Prevalence and Predictors of Gestational Diabetes Mellitus in Sub-Saharan Africa: A 10-Year Systematic Review

BACKGROUND

Gestational diabetes mellitus (GDM) remains a global public health problem, which affects the well-being of mothers and their children in sub-Saharan Africa (SSA). Studies conducted in different geographical areas provide varied results on its prevalence and predictors. Understanding the extent and predictors of GDM in SSA is important for developing effective interventions and policies. Thus, this review aimed to investigate the prevalence of GDM and its predictive factors in sub-Saharan Africa.

METHODS

We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards in this review. An extensive search of the PubMed, Web of Sciences and EMBASE databases was carried out covering papers from 2012 to 2022 to assess the prevalence and predictors of GDM. Microsoft Excel 2019 was utilised for study management. GraphPad Prism Version 8.0 and the MedCalc statistical software were employed for data analysis. The findings were analysed using textual descriptions, tables, forest plots and heat maps.

RESULTS

Using 30 studies with 23,760 participants that satisfied the inclusion criteria, the review found the overall prevalence of GDM in SSA to be 3.05% (1.85%-4.54%). History of preterm delivery, alcohol consumption, family history of diabetes, history of stillbirths, history of macrosomia, overweight or obesity and advanced mother age were all significant predictors of gestational diabetes. Additionally, various biomarkers such as haemoglobin, adiponectin, leptin, resistin, visfatin, vitamin D, triglycerides and dietary intake type were identified as significant predictors of GDM.

CONCLUSION

In sub-Saharan Africa, there is a high pooled prevalence of gestational diabetes mellitus. In the light of the predictors of GDM identified in this review, it is strongly recommended to implement early screening for women at risk of developing gestational diabetes during their pregnancy. This proactive approach is essential for enhancing the overall well-being of both mothers and children.

Nutritional Assessment of Plant-Based Meat Products Available on Hong Kong Market: A Cross-Sectional Survey

BACKGROUND

Plant-based meat (PBM) takes up ever-increasing market shares and draws great attention from both customers and retailers these days. However, little is known about the nutritional quality of PBM products.

OBJECTIVE

This study intended to profile and evaluate the overview nutrition of PBM with equivalent meat products on the Hong Kong market.

METHODS

We conducted a cross-sectional survey of 274 PBM and 151 meat products from 27 different brands on the Hong Kong market in October 2022. The nutritional differences between PBM and meat products were assessed using analysis of covariance (ANCOVA) and two independent sample t-test. The nutritional quality of PBMs was evaluated according to nutrient reference value, front-of-package (FoP) criteria and nutritional score.

RESULTS

PBM had relatively lower energy density, total fat, saturated fat, protein, and salt compared to meat. According to the FoP criteria, 91.36%, 17.88%, and 99.34% of PBMs were labeled as medium to high in fat, salt, and sugar, respectively. Through ingredient analysis of 81 PBM products, soy and canola were the main source of protein and fat.

CONCLUSIONS

PBM products have a roughly better nutrient quality compared to muscle-based meat, though there is still potential for further refinement in terms of production, consumption, and regulation.

Association between blood selenium levels and gestational diabetes mellitus: A systematic review and meta-analysis

Introduction

The association between blood (serum or plasma) selenium concentrations and gestational diabetes mellitus (GDM) has been evaluated in some studies. However, the reported findings are debatable, and only case-control and cross-sectional studies were included.

Objective

This research aimed to assess the association between blood selenium levels and GDM by analyzing existing literature. To provide a reference for the prevention and treatment of GDM, we included prospective studies which are not included in previous studies to collate more high-quality evidence and better test the etiological hypothesis between blood Se concentrations and GDM.

Methods

The PubMed, EMBASE, and Web of Science databases were retrieved for literature up to September 2022, and relevant references were manually searched. Raw data from relevant studies were extracted, and a random effect model was adopted for meta-analysis. The total effects were reported as weighted mean differences. All data were analyzed using Stata 16.0 software.

Results

Fourteen studies involving 890 pregnant women with GDM and 1618 healthy pregnant women were incorporated in the meta-analysis. Pregnancies with GDM had significantly lower blood selenium levels than those with normal glucose tolerance (weighted mean difference = -8.11; 95% confidence interval: -12.68 to -3.54, P = 0.001). Subgroup analyses showed that the association between blood selenium levels and GDM was consistent in the residents of Asia and Africa, but not in European. This trend was significant in the second and third trimester subgroups, but not in the first trimester subgroup. Articles published in 2006-2015 also showed this trend, but those published before 2005 and 2016-2019 did not show significant results. This difference was evident in non-prospective studies, but not significant in prospective studies. Studies using the Carpenter and Coustan diagnostic criteria were consistent with this trend, whereas studies using other diagnostic criteria found no differences. In addition, in terms of blood selenium measurement methods, atomic absorption spectrometry showed more significant differences than other methods. In the subgroup analysis based on the sample size of included studies and the quality of the studies, each subgroup showed statistical differences.

Conclusion

Lower blood selenium concentrations are associated with GDM as shown in our study. Therefore, supplementing an appropriate amount of selenium may be helpful for GDM prevention and treatment.

Association of Selenium Levels with Gestational Diabetes Mellitus: An Updated Systematic Review and Meta-Analysis

Several studies have investigated the association between selenium levels and gestational diabetes mellitus (GDM); however, their results are not conclusive. This systematic review and meta-analysis aimed to update and draw conclusions regarding the evidence from published studies that investigated selenium levels in relation to GDM. PubMed, Google Scholar, Cochrane Library and ScienceDirect were searched for studies related to selenium and GDM, published from the inception of each database through to July 2022. The meta-analysis was conducted by measuring the standardized mean difference (SMD) between the selenium levels of women with GDM and those pregnant without GDM (control group). Stratified meta-analysis, meta-regression analysis and reporting bias were applied. The "meta" package in the open-access software R was used to analyze all of the data. A total of 12 studies, including 940 pregnant women with GDM and 1749 controls met this study's inclusion criteria. The selenium levels were significantly lower in women with GDM compared with the control group (SMD = -0.66; 95% confidence interval (CI): (-1.04, -0.28); p ≤ 0.001). Due to significant heterogeneity (I2 = 94%, Cochrane Q = 186.7; p ≤ 0.0001), the random-effects model was followed. The stratified meta-analysis showed that the selenium levels were lower in the cases compared with the normal controls in the third trimester (SMD = -1.85 (-3.03, -0.66); p ≤ 0.01). The same trend was observed in the studies published before the year 2014 (SMD = -0.99 (-1.70, -0.28); p ≤0.01) and those published in or after 2014 (SMD = -0.45 (-0.90, 0.00); p = 0.05). None of the investigated covariates in the meta-regression analysis (each study's geographic location, trimester of selenium quantification, World Bank economic classification, method of selenium determination, study design, study quality score, publication year and study's sample size) were significantly associated with the selenium SMD. The current evidence indicates that selenium levels are lower among women with GDM in comparison to those without GDM; however, after the correction of the reporting bias, the result was no longer significant. Further studies with more prospective designs are needed to confirm this evidence and explain the function of selenium in GDM throughout pregnancy.

Associations between Circulating SELENOP Level and Disorders of Glucose and Lipid Metabolism: A Meta-Analysis

Selenoprotein P (SELENOP) is an extracellular antioxidant, selenium transporter, and hepatokine interfering with glucose and lipid metabolism. To study the association between the circulating SELENOP concentration and glucose and lipid metabolic diseases (GLMDs), including gestational diabetes (GD), metabolic syndrome (MetS), non-alcoholic fatty liver disease, obesity, and type 2 diabetes, as well as the individual markers, a meta-analysis was conducted by searching multiple databases from their establishment through March 2022 and including 27 articles published between October 2010 and May 2021, involving 4033 participants. Participants with GLMDs had higher levels of SELENOP than those without GLMDs (standardized mean difference = 0.84, 95% CI: 0.16 to 1.51), and the SELENOP levels were positively correlated with the markers of GLMDs (pooled effect size = 0.09, 95% CI: 0.02 to 0.15). Subgroup analyses showed that the SELENOP concentrations were higher in women with GD and lower in individuals with MetS than their counterparts, respectively. Moreover, SELENOP was positively correlated with low-density lipoprotein cholesterol, but not with the other markers of GLMDs. Thus, the heterogenicity derived from diseases or disease markers should be carefully considered while interpreting the overall positive association between SELENOP and GLMDs. Studies with a larger sample size and advanced design are warranted to confirm these findings.

Materno-fetal iron transfer and the emerging role of ferroptosis pathways

A successful pregnancy and the birth of a healthy baby depend to a great extent on the controlled supply of essential nutrients via the placenta. Iron is essential for mitochondrial energy supply and oxygen distribution via the blood. However, its high reactivity requires tightly regulated transport processes. Disturbances of maternal-fetal iron transfer during pregnancy can aggravate or lead to severe pathological consequences for the mother and the fetus with lifelong effects. Furthermore, high intracellular iron levels due to disturbed gestational iron homeostasis have recently been associated with the non-apoptotic cell death pathway called ferroptosis. Therefore, the investigation of transplacental iron transport mechanisms, their physiological regulation and potential risks are of high clinical importance. The present review summarizes the current knowledge on principles and regulatory mechanisms underlying materno-fetal iron transport and gives insight into common pregnancy conditions in which iron homeostasis is disturbed. Moreover, the significance of the newly emerging ferroptosis pathway and its impact on the regulation of placental iron homeostasis, oxidative stress and gestational diseases will be discussed.

The association between serum selenium level and gestational diabetes mellitus: A systematic review and meta-analysis

BACKGROUND

The relationship between serum selenium level and gestational diabetes mellitus (GDM) is controversial. The purpose is to update and summarize previous studies to understand the relationship in more detail.

METHODS

PubMed, The Cochrane Library, EMBASE, Web of science, CNKI, WANFANG DATA and Cqvip were searched for studies published up to 3 September 2021. The random-effects model was used to measure the combined estimation. The overall effect was reported in a standard mean difference (SMD) and 95% confidence interval (95% CI). All data were analysed by Review Manager 5.4.

RESULTS

Twenty-seven studies involving 1588 patients with GDM and 2450 healthy pregnant women contributed to this meta-analysis. Selenium level was significantly lower in women with GDM than those without GDM (SMD = -1.29; 95% CI: -1.60 to -0.97, p < 0.00001). Subgroup analyses showed that such trend was consistent within the non-European population (Asia: SMD = -1.44; 95% CI: -1.79 to -1.08, p < 0.00001; Africa: SMD = -2.62; 95% CI: -4.50 to -0.74, p = 0.006) and in the second and third trimesters (the second trimester: SMD = -1.41; 95% CI: -1.82 to -0.99, p < 0.00001; the third trimester: SMD = -1.54; 95% CI: -2.09 to -0.98, p < 0.00001), but not within the European population (SMD = -0.47; 95% CI: -1.09 to 0.16, p = 0.14) or in the first trimester (SMD = -0.52; 95% CI: -1.13 to 0.10, p = 0.10).

CONCLUSIONS

This meta-analysis showed that the serum selenium level of patients with GDM was lower than that in healthy pregnant women, especially within the non-European population and in the second and third trimesters.

Plasma levels of trace element status in early pregnancy and the risk of gestational diabetes mellitus: A nested case-control study

PURPOSE

We investigated the impacts of plasma levels of magnesium (Mg), zinc (Zn), calcium (Ca), iron (Fe), copper (Cu), selenium (Se), and chromium (Cr) on GDM risk and the potential mediation effect of blood glucose levels on the relationship between trace elements and GDM risk.

METHODS

This nested case-control study was based on data from a birth cohort study conducted in Wuhan, China in 2013-2016. A total of 305 GDM cases and 305 individually-matched controls were included in the study. Conditional logistic regression models were used to estimate the associations between plasma trace element concentrations and GDM risk. A mediation analysis was conducted to explore whether blood glucose levels act as a mediator between trace element levels and GDM risk.

RESULTS

An IQR increment in plasma levels of Fe and Cu was associated with a significant increase in GDM risk [OR = 2.04 (95 % CI 1.62, 2.57) and OR = 1.52 (95 % CI 1.25, 1.82)], respectively. On the other hand, an IQR increment in plasma levels of Zn and Ca was associated with a significant decrease in GDM risk [OR = 0.55 (95 % CI 0.43, 0.71) and OR = 0.72 (95 % CI 0.56, 0.92)], respectively. The mediation analysis showed significant mediation of the association between Cu and GDM risk via the FBG (%mediated: 19.27 %), 1 h-PBG (12.64 %), 2h-PBG (28.44 %) pathways.

CONCLUSIONS

Plasma levels of Zn and Ca were negatively associated with GDM risk, while Fe and Cu were positively associated. Blood glucose levels act as a mediator between plasma trace element exposures and GDM risk.

Is serum zinc status related to gestational diabetes mellitus? A meta-analysis

Gestational diabetes mellitus (GDM) is a common medical disorder that begins during pregnancy. The present work aimed to investigate the relationship of maternal or foetal circulatory zinc levels with GDM. Related studies were retrieved against the PubMed/Medline, Web of Science, Scopus databases till July 2020. The overall effects were expressed as standard mean difference (SMD). Furthermore, the random effects model was used to assess the summarised risk ratios (SRRs) to determine the relationship between zinc and the risk of GDM. A total of 15 articles involving were retrieved for meta‐analysis; in the meantime, 4955 subjects including 1549 GDM cases were enrolled for quantitative analysis. Compared with normal control, GDM cases had decreased circulating zinc level on the whole, but the difference was not statistically significant (SMD = −0.40, 95%CI: −0.80 to −0.00, P = 0.05). Interestingly, upon subgroup analysis stratified by serum zinc content but not plasma zinc concentration, there was significant difference in zinc content between GDM cases and normal controls (SMD = −0.56; 95%CI: −1.07 to −0.04, P = 0.03). Meanwhile, subgroup analysis also revealed similar tendency among the Asians and during the 2nd trimester, but not among the Caucasians or during the 1st or 3rd trimester. Data extracted from four studies that compared pregnant women with GDM in the high level of zinc and GDM in the low level of zinc yielded an SRR of 0.929 (95%CI: 0.905–0.954). According to existing evidence, the serum zinc content decreases among GDM cases compared with subjects with no abnormality in glucose tolerance, in particular among the Asians and during the second trimester. Nonetheless, more well designed prospective study should be carried out for understanding the dynamic relationship of zinc level with the incidence of GDM.

Effect of Iodine and Selenium on Proliferation, Viability, and Oxidative Stress in HTR-8/SVneo Placental Cells

Adequate maternal micronutrition is vital for placental formation, fetal growth, and development. Oxidative stress adversely affects placental development and function and an association between deficient placental development, oxidative stress, and micronutrient deficiency has been observed. Selenium and iodine are two essential micronutrients with antioxidant properties. Epidemiological studies have shown that poor micronutrient status in pregnant women is associated with a higher incidence of pregnancy complications. The aim of this study was to determine how selenium, iodine, and their combination impact oxidative stress in placental trophoblast cells. HTR8/SVneo extravillous trophoblasts were supplemented with a concentration range of organic and inorganic selenium, potassium iodide, or their combination for 24 h. Oxidative stress was then induced by treating cells with menadione or H₂O₂ for 24 h. Cell viability and lipid peroxidation as the biomarker of oxidative stress were assessed at 48 h. Both menadione and H₂O₂ reduced cell viability and increased lipid peroxidation (P < 0.05). Greater cell viability was found in selenium-supplemented cells when compared with vehicle treated cells (P < 0.05). Selenium and iodine supplementation separately or together were associated with lower lipid peroxidation compared with vehicle control (P < 0.05). Supplementation with the combination of selenium and iodine resulted in a greater reduction in lipid peroxidation compared with selenium or iodine alone (P < 0.05). Oxidative stress negatively impacts trophoblast cell survival and cellular integrity. Selenium and iodine protect placental trophoblasts against oxidative stress. Further research is warranted to investigate the molecular mechanisms by which selenium and iodine act in the human placenta.

Associations of Serum Selenium Levels in the First Trimester of Pregnancy with the Risk of Gestational Diabetes Mellitus and Preterm Birth: a Preliminary Cohort Study

Women with gestational diabetes mellitus (GDM) may have lower serum selenium levels than healthy controls, which may be associated with preterm birth. We explored the association of serum selenium levels in early pregnancy with the risk of GDM and preterm birth among Chinese women. We included 398 women with a singleton pregnancy, who were followed up prospectively from the first prenatal visit until delivery. Serum selenium levels were measured in the first trimester. After delivery, data concerning mothers and their children were sourced from medical records by researchers who were blind to the participants' selenium status. Of the 398 women, 71 (17.8%) had GDM, 21(5.3%) had preterm birth, and 266 (66.8%) had selenium deficiency (serum selenium < 70 μg/L). Women in the upper three quartiles of serum selenium level did not have a significantly lower risk of GDM or preterm birth than those in the lowest quartile after adjustment for covariates (all p > 0.05). When serum selenium levels were classified as normal or deficient, the risk of GDM or preterm birth among women with normal serum selenium levels was still not lower than that of women with deficient serum selenium levels after adjustment for covariates (all p > 0.05). Although selenium deficiency was common in the Chinese women in our cohort, our results indicate that low serum selenium level during early pregnancy may not be a strong predictor of the risk of GDM and preterm birth. However, our sample size was small, and future studies with larger populations are warranted.

A Review of the Potential Interaction of Selenium and Iodine on Placental and Child Health

A healthy pregnancy is important for the growth and development of a baby. An adverse pregnancy outcome is associated with increased chronic disease risk for the mother and offspring. An optimal diet both before and during pregnancy is essential to support the health of the mother and offspring. A key mediator of the effect of maternal nutrition factors on pregnancy outcomes is the placenta. Complicated pregnancies are characterized by increased oxidative stress in the placenta. Selenium and iodine are micronutrients that are involved in oxidative stress in placental cells. To date, there has been no comprehensive review investigating the potential synergistic effect of iodine and selenium in the placenta and how maternal deficiencies may be associated with increased oxidative stress and hence adverse pregnancy outcomes. We undertook a hypothesis-generating review on selenium and iodine, to look at how they may relate to pregnancy complications through oxidative stress. We propose how they may work together to impact pregnancy and placental health and explore how deficiencies in these micronutrients during pregnancy may impact the future health of offspring.

First Trimester Microelements and their Relationships with Pregnancy Outcomes and Complications

Microelements involved in the oxidative balance have a significant impact on human health, but their role in pregnancy are poorly studied. We examined the relationships between first trimester levels of selenium (Se), iron (Fe), zinc (Zn), and copper (Cu), as well as maternal characteristics and pregnancy results. The data came from a Polish prospective cohort of women in a single pregnancy without chronic diseases. A group of 563 women who had a complete set of data, including serum microelements in the 10–14th week was examined, and the following were found: 47 deliveries <37th week; 48 cases of birth weight <10th and 64 newborns >90th percentile; 13 intrauterine growth restriction (IUGR) cases; 105 gestational hypertension (GH) and 15 preeclampsia (PE) cases; and 110 gestational diabetes mellitus (GDM) cases. The microelements were quantified using mass spectrometry. The average concentrations (and ranges) of the elements were as follows: Se: 60.75 µg/L (40.91–125.54); Zn: 618.50 µg/L (394.04–3238.90); Cu: 1735.91 µg/L (883.61–3956.76); and Fe: 1018.33 µg/L (217.55–2806.24). In the multivariate logistic regression, we found that an increase in Se of 1 µg/L reduces the risk of GH by 6% (AOR = 0.94; p = 0.004), the risk of IUGR by 11% (AOR = 0.89; p = 0.013), and the risk of birth <34th week by 7% (but close to the significance) (AOR = 0.93; p = 0.061). An increase in Fe of 100 µg/L reduces the risk of PE by 27% (AOR = 0.73; p = 0.009). In the multivariable linear regression, we found negative strong associations between prepregnancy BMI, Se (β = −0.130; p = 0.002), and Fe (β = −0.164; p < 0.0001), but positive associations with Cu (β = 0.320; p < 0.000001). The relationships between Se and maternal age (β = 0.167; p < 0.0001), Se and smoking (β = −0.106; p = 0.011) and Cu, and gestational age from the 10–14th week (β = 0.142; p < 0.001) were also found. Secondary education was associated with Zn (β = 0.132; p = 0.004) and higher education was associated with Cu (β = −0.102; p = 0.023). A higher financial status was associated with Fe (β = 0.195; p = 0.005). Other relationships were statistically insignificant. Further research is needed to clarify relationships between first trimester microelements and pregnancy complications. In addition, attention should be paid to lifestyle-related and socioeconomic factors that affect microelement levels.

Evaluating associations between early pregnancy trace elements mixture and 2nd trimester gestational glucose levels: A comparison of three statistical approaches

OBJECTIVE

Studies have shown that individual trace element levels might be associated with abnormal glycemic status, with implications for diabetes. Few studies have considered these trace elements as a mixture and their impact on gestational glucose levels. Comparing three statistical approaches, we assessed the associations between essential trace elements mixture and gestational glucose levels.

METHODS

We used data from 1720 women enrolled in the Eunice Kennedy Shriver National Institute of Child Health and Human Development's Fetal Growth Study, for whom trace element concentrations (zinc, selenium, copper, molybdenum) were measured by inductively coupled plasma mass spectrometry (ICP-MS) using plasma collected during the 1st trimester. Non-fasting glucose levels were measured during the gestational diabetes mellitus (GDM) screening test in the 2nd trimester. We applied (1) Bayesian Kernel Machine Regression (BKMR); (2) adaptive Least Absolute Shrinkage and Selection Operator (LASSO) in a mutually adjusted linear regression model; and (3) generalized additive models (GAMs) to evaluate the joint associations between trace elements mixture and glucose levels adjusting for potential confounders.

RESULTS

Using BKMR, we observed a mean 2.7 mg/dL higher glucose level for each interquartile increase of plasma copper (95% credible interval: 0.9, 4.5). The positive association between plasma copper and glucose levels was more pronounced at higher quartiles of zinc. Similar associations were detected using adaptive LASSO and GAM. In addition, results from adaptive LASSO and GAM suggested a super-additive interaction between molybdenum and selenium (both p-values = 0.04).

CONCLUSION

Employing different statistical methods, we found consistent evidence of higher gestational glucose levels associated with higher copper and potential synergism between zinc and copper on glucose levels.

Serum selenium level and gestational diabetes mellitus: a systematic review and meta-analysis

Background

The association between serum selenium level and gestational diabetes mellitus (GDM) is controversial. The aim of our study was to systematically review available literature linking selenium to GDM for a comprehensive understanding of the relationship between serum selenium level and GDM in human.

Methods

PubMed, The Cochrane Library and Medline were searched for studies published up to August 2016. Manual searches of references of the relevant original studies were carried out. Pooled estimates were measured using the fixed or random effect model. Overall effect was reported in a standard mean difference (SMD). All data were analyzed with Review Manager 5.3 and Stata 12.0.

Results

Of 44 references reviewed, seven studies involving 569 patients met our inclusion criteria and contributed to meta-analysis. All the studies were used to evaluate the relationship between serum selenium level and GDM. Selenium level was significantly lower in women with GDM than those without GDM (SMD = −1.17; 95 % CI: −1.98 to −0.35, P = 0.005). Subgroup analysis showed that such trend was consistent within the non-Caucasian population (Asia: SMD = −2.82; 95 % CI: −5.21 to −0.43, P = 0.02; Africa: SMD = −0.56; 95 % CI: −1.07 to −0.05, P = 0.03) and in the third trimester (SMD = −1.78; 95 % CI: −3.04 to −0.52, P = 0.006), but not within the Caucasian population (Europe: SMD = −0.6; 95 % CI: −1.98 to 0.78, P = 0.39) or in the second trimester (SMD = −0.68; 95 % CI: −1.6 to 0.25, P = 0.15).

Conclusions

The available evidences suggested that serum selenium level was lower in women with GDM than those with normal glucose tolerance, especially within the non-Caucasian population and in the third trimester. However, well-designed prospective studies are needed to understand dynamic associations between selenium status and GDM risk.

The metallome of the human placenta in gestational diabetes mellitus

Obtaining the knowledge of the "omics" and therefore of the metallomics of gestational diabetes mellitus (GDM) appears to be a necessary task to obtain information about the molecular causes of this disease. In this study, the metallome of GDM and of other types of diabetes mellitus was first reviewed. The comparative analysis of the published data revealed that no GDM elemental markers could be identified with sufficient reliability in blood or in the other considered samples, with the partial exception of selenium. The placenta was chosen as an alternative target organ for the analysis of the GDM metallome. The full elemental average composition of 19 healthy placentas was obtained by ICP-MS. Analyses were then performed on 28 placentas from women affected by GDM. The statistical tests and the principal component analysis evidenced that cadmium was found in lower concentrations and selenium was found in higher concentrations in GDM placentas than in those of the control group. These results were interpreted in light of literature data, and they attract attention on two key elements for understanding the molecular pathways of GDM.

Serum magnesium, iron and ferritin levels in patients with diabetic retinopathy attending Makkah Eye Complex, Khartoum, Sudan

Diabetic retinopathy is the most common complications of diabetes mellitus that, in most occasions, lead to blindness. Multiple evidences linked the serum magnesium, iron and ferritin disturbance with diabetes and its complications. A case-control study was conducted at Makkah Eye Complex, Khartoum, Sudan, to compare the levels of serum magnesium, iron and ferritin in patients with diabetic retinopathy with diabetic patients without diabetic retinopathy (controls). Findings indicate that all patients had type 2 diabetes. The two groups (50 in each arm) were well matched in their basic characteristics. Median (25th-75th interquartile) of serum magnesium in patients with diabetic retinopathy were significantly lower than patients without diabetic retinopathy [1.48 (0.75-1.64) vs. 1.92 (1.4-2.3)mg/dl, P = 0.022]. The median of serum iron and ferritin were lower in cases than control group but did not reach a statistical significance [20.5 (17.2-48.0) vs. 27.0 (16.0-54.0) μg/dl, P = 0.568; 98.0 (45.0-134.75) vs. 101.0 (47.0-161.0) μg/l, P = 0.818]. The duration of diabetes [16.5 (9.3) vs. 11.2 (6.6) years; P = 0.014] and haemoglobin level [13.7 (0.9) vs. 12.5 (2.0) g/dl; P = 0.039] were significantly higher in cases group than control group. A significant inverse correlation was observed between serum magnesium and iron levels. Twenty (40 %) patients had severe non-proliferative diabetic retinopathy with mild macular edema, which is the most prevalent type among the cases group. Hypomagnesaemia among diabetic patients was associated with diabetic retinopathy, while serum iron and ferritin have no significant effect in this setting. Severe non-proliferative diabetic retinopathy with mild macular edema is the prevalent type in this study.