Is there a genetic variation association in the IL-10 and TNF alpha promoter gene with gestational diabetes mellitus?

15-Hydroxyprostaglandin dehydrogenase inhibitor SW033291 ameliorates hepatic abnormal lipid metabolism, ER stress, and inflammation through PGE2/EP4 in T2DM mice

Type 2 diabetes mellitus (T2DM) is a rapidly growing epidemic that results in increased morbidity, mortality, and soaring medical costs. Prostaglandin E₂ (PGE₂), a vital lipid mediator, has been reported to protect against hepatic steatosis, inflammation, endoplasmic reticulum (ER) stress, and insulin resistance, indicating its potential therapeutic role in T2DM. PGE₂ can be degraded by 15-hydroxyprostaglandin dehydrogenase (15-PGDH). SW033291, an inhibitor of 15-PGDH, has been reported to increase PGE₂ levels, however, the effect of SW033291 in T2DM remains to be explored. This study aims to evaluate whether SW033291 protects against T2DM and explore its potential mechanisms. A T2DM mouse model was established through high-fat diet/streptozotocin injection, while palmitic acid-treated mouse primary hepatocytes were used as insulin-resistant cell models. SW033291 treatment reduced body weight, fat weight, fasting blood glucose, and improved impaired glucose tolerance and insulin resistance in T2DM mice. More importantly, SW033291 alleviated steatosis, inflammation, and ER stress in the liver of T2DM mice. Mechanistically, SW033291 decreased the expressions of SREBP-1c and ACC1, and increased the expression of PPARα in T2DM mice. Additionally, SW033291 inhibited NF-κB and eIF2α/CHOP signaling in T2DM mice. Further, we showed that the protective effects of SW033291 on the above-mentioned pathophysiological processes could be hindered by inhibition of the PGE₂ receptor EP4. Overall, our study reveals a novel role of SW033291 in alleviating T2DM and suggests its potential as a new therapeutic strategy for T2DM.

A Clinical Update on Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) traditionally refers to abnormal glucose tolerance with onset or first recognition during pregnancy. GDM has long been associated with obstetric and neonatal complications primarily relating to higher infant birthweight and is increasingly recognized as a risk factor for future maternal and offspring cardiometabolic disease. The prevalence of GDM continues to rise internationally due to epidemiological factors including the increase in background rates of obesity in women of reproductive age and rising maternal age and the implementation of the revised International Association of the Diabetes and Pregnancy Study Groups' criteria and diagnostic procedures for GDM. The current lack of international consensus for the diagnosis of GDM reflects its complex historical evolution and pragmatic antenatal resource considerations given GDM is now 1 of the most common complications of pregnancy. Regardless, the contemporary clinical approach to GDM should be informed not only by its short-term complications but also by its longer term prognosis. Recent data demonstrate the effect of early in utero exposure to maternal hyperglycemia, with evidence for fetal overgrowth present prior to the traditional diagnosis of GDM from 24 weeks' gestation, as well as the durable adverse impact of maternal hyperglycemia on child and adolescent metabolism. The major contribution of GDM to the global epidemic of intergenerational cardiometabolic disease highlights the importance of identifying GDM as an early risk factor for type 2 diabetes and cardiovascular disease, broadening the prevailing clinical approach to address longer term maternal and offspring complications following a diagnosis of GDM.

Interleukin-10 levels and risk of gestational diabetes mellitus: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Association of interleukin-10 (IL-10) polymorphism with diabetes and its complication was recently established, while there were few kinds of research considering the potential role of IL-10 in gestational diabetes (GDM). This study aimed to systematically review the association between serum IL-10 level and GDM susceptibility.

METHODS

A comprehensive literature search for the published studies in PubMed, Scopus, CENTRAL (Cochrane Central Register of Controlled Trials), and Google Scholar databases was performed for English language papers published up to 31st July 2020. Following key terms were used: "Cytokine level" OR "Interleukin-10" OR "IL-10," OR "Pro-inflammatory Cytokines" OR "gestational diabetes mellitus" OR "GDM." Fixed or random-effects models were used to estimate the pooled SDM and 95% confidence intervals (CIs). Begg's funnel plot was used to assess the potential for publication bias.

RESULTS

In our meta-analysis, a total of ten studies for the risk of GDM involving 609 GDM cases and 664 controls were included. No significant association between IL-10 levels and risk of GDM as compared to control subjects (SMD = -0.09, 95% CI = -0.73 to 0.55). Subgroup analysis based on ethnicity also does not reveal any association between IL-10 levels and risk of GDM as compared to control subjects has more or less similar trends in Caucasian (SMD = -0.07, 95% CI = -0.58 to 0.45) as well as Asian population (SMD = -0.03, 95% CI = -1.56 to 1.49).

CONCLUSION

Our findings suggest that the serum IL-10 level may not be significantly associated with an increased risk of susceptibility to GDM. Further well-designed prospective studies embedded with a large sample size are needed to confirm these findings.

Gestational Diabetes Mellitus: The Genetic Susceptibility Behind the Disease

Gestational diabetes mellitus (GDM), a type of pregnancy-specific glucose intolerance or hyperglycemia, is one of the most common metabolic disorders in pregnant women with 16.9% of the global prevalence of gestational hyperglycemia. Not only are women with GDM likely to develop T2DM, but their children are also at risk for birth complications or metabolic disease in adulthood. Therefore, identifying the potential risk factors for GDM is very important in the prevention and treatment of GDM. Previous studies have shown that genetic predisposition is an essential component in the occurrence of GDM. In this narrative review, we describe the role of polymorphisms in different functional genes associated with increased risk for GDM, and available evidence on genetic factors in the risk of GDM is summarized and discussed.

IL-1β and IL-10 gene polymorphisms in women with gestational diabetes

AIMS

Gestational diabetes (GDM) is carbohydrate intolerance occurring in pregnant women. In the GDM pathogenesis, the low-grade inflammation plays a significant role. Various inflammatory mediators are considered to be risk factors leading to GDM development including cytokines. Studies suggest that some cytokines such as: IL-1β and IL-10 play an important role in GDM pathogenesis. The aim of the study was to examine the associations between IL-1β rs16944, and IL-10 rs1800872 gene polymorphisms and GDM.

METHODS

This study included 204 pregnant women with GDM and 207 pregnant women with normal glucose tolerance. The diagnosis of GDM was based on a 75-g oral glucose tolerance test administered at 24-28 weeks' gestation. Among the pregnant women with GDM, 152 (75%) were treated with diet control alone throughout the pregnancy, whereas the remaining 52 (25%) were treated with diet control and insulin until delivery.

RESULTS

There were no statistically significant differences in the distribution of IL-1β rs16944 and IL-10 rs1800872 between GDM and healthy women. However among women treated with insulin, we observed the increased frequency of IL-1β rs16944 AA genotype carriers. Additionally, we observed increased daily insulin requirement in women with IL-1β rs16944 AA genotype. Moreover, women with IL-10 rs1800872 AA genotype had higher body mass and BMI before pregnancy as well as higher body mass and BMI increase during pregnancy.

CONCLUSIONS

The results of our study suggest the association between IL-1β rs16944 AA genotype and increased frequency of the need of insulin treatment as well as increased daily insulin requirement.

Role of immunological markers in gestational diabetes mellitus-a brief review

Gestational Diabetes Mellitus (GDM) is a condition which develops due to insulin resistance. There are a number of immunological markers (IL-6, TNF-α, IL-10, etc), which play significant role during normal pregnancy and their irregular levels could likely cause some level of insulin resistance. There are studies which have compared the levels of different immunological mediators in GDM affected females and their healthy controls, but their findings are little controversial. Some of the studies have reported increased levels of IL-6, TNF-α, adiponectin, leptin, in females affected with GDM, while others do not confirm this. We have tried to summarize, in this short review, the findings of research studies being conducted globally, which have reported the association of insulin resistance, GDM and immunological markers. Our review suggests that there is a need for high quality data on the immunological parameters associated with GDM, especially from India.

Lactobacillus acidophilus alleviates type 2 diabetes by regulating hepatic glucose, lipid metabolism and gut microbiota in mice

Diabetes, an endocrine and metabolic disorder, has become the third most non-infectious chronic disease that threatens human health. Type 2 diabetes (T2D) accounts for more than 90% of diabetic patients, mainly caused by environmental factors. Lactic acid bacteria (LAB) exhibit several health benefits to the host including regulating glucose and lipid metabolism and improving oxidative stress and inflammatory response. However, the anti-diabetic mechanism of probiotics has not been elucidated clearly. In this study, the anti-diabetic effects of Lactobacillus acidophilus KLDS1.1003 and KLDS1.0901 on T2D mice were assessed. Oral administration of L. acidophilus KLDS1.1003 and KLDS1.0901 for 6 weeks significantly improved the epithelial barrier function, which in turn lowered inflammation cytokines, including IL-8, TNF-α and IL-1β in liver and colon tissue, and prevented liver and colon tissue injuries to some extent. Additionally, L. acidophilus treatment regulated the expression genes that are related to glucose and lipid metabolism. The two tested strains down-regulated the expression of glycogen synthase kinase 3β (GSK-3β), fatty acid synthase (FAS) and sterol regulatory element-binding transcription factor 1c (SREBP-1c), and up-regulated the expression of protein kinase B (Akt). However, L. acidophilus KLDS1.0901 is better for improving T2D than L. acidophilus KLDS1.1003. Further research showed that L. acidophilus KLDS1.0901 supplementation could reshape gut microbiota, increasing short chain fatty acid-producing bacteria (Blautia, Roseburia and Anaerotruncus) and the level of SCFAs and decreasing the relative abundance of Gram-negative bacteria such as Desulfovibrio, Alistipes and Bacteroides. Notably, L. acidophilus KLDS1.0901 treatment restored the structure of gut microbiota similar to the control group. These findings suggested that L. acidophilus KLDS1.0901 might be used as a new type of antidiabetic drug candidate.

Novel Interleukin-10 Gene Polymorphism Is Linked to Gestational Diabetes in Taiwanese Population

Objective: The association of interleukin-10 (IL-10) polymorphism with diabetes and its complication was recently established, while there were few researches considering the potential role of IL-10 in gestational diabetes (GDM). This study aimed to investigate the association between IL-10 gene rs1800896 (−1082 A/G), rs1800871 (−819 T/C), rs1800872 (−592 A/C), and rs3021094 (3388 A/C) single nucleotide polymorphisms (SNPs) and GDM susceptibility.

Methods: This study included 72 GDM patients and 100 healthy pregnant women. Direct sequencing of the products from polymerase chain reactions of the extracted genomic DNA from study subjects were conducted for analyzing IL-10 gene polymorphism and further genotype frequencies were compared. Plasma IL-10 concentration was measured by ELISA method.

Results: The results revealed no significant difference in −592 A/C, −819 T/C, and −1082 A/G genotypes. Significantly increased prevalence of A allele (P = 0.028, OR = 1.69, 95% CI = 1.081–2.64) and A/A genotype (P = 0.031, OR = 2.881, 95% CI = 1.145–7.250) at a previously un-characterized rs3021094 SNP were discovered in the GDM group. Increased IL-10 levels and insulin resistance were also related to the genotype of rs3021094. The risk of GDM was increased when IL-10 level was over 6.5 pg/ml.

Conclusion: Our study demonstrated that A allele and A/A genotype of rs3021094 SNP in IL-10 gene were linked to increased risk for GDM, IL-10 plasma level and insulin resistance, which could be potential targets for early screening and detection of GDM.

Maternal serum level of TNF-α in Nigerian women with gestational diabetes mellitus

Introduction

alterations in the circulating level of tumour necrosis factor-α (TNF-α) has been proposed to be involved in the pathogenesis of gestational diabetes mellitus (GDM), but its role is not completely understood, findings from studies done across different ethnic groups are often inconsistent. We carried out this study to determine maternal serum level of TNF-a and it's association with body weight status in a group of Nigerian women with GDM.

Methods

a cross sectional analytical study conducted among 169 pregnant women, 85 with GDM and 84 with normal gestation. Diagnosis of GDM was made between 24-28 weeks gestation according to the WHO diagnostic criteria. Maternal serum level of TNF-α was measured and compared between the study groups.

Results

maternal serum TNF-α level was significantly higher in the pregnant women with GDM than in the controls (2.50 ± 0.30 vs. 2.10 ± 0.30 pg/ml, p < 0.05). Also when comparing the serum TNF-α levels of the pregnant women with GDM and the controls for each level of body mass index, serum TNF-α levels remained significantly higher in both the normal weight and overweight pregnant women with GDM compared to their matched controls (2.40 ± 0.30 vs. 1.90 ± 0.20 pg/ml, p < 0.05) and (2.60 ± 0.30 vs. 2.30 ± 0.20 pg/ml, p < 0.05) respectively.

Conclusion

it is concluded that pregnant women with GDM in this study have higher maternal serum TNF-α level compared to the pregnant women with normal glucose tolerance regardless of body weight status.

An association between IL-10 promoter polymorphisms and diabetic nephropathy: a meta-analysis of case-control studies

Background

This study aimed to synthesize evidence on the association between IL-10 gene (-819 C/T, -1082 A/G, -592 A/C) polymorphisms and the risk of developing diabetic nephropathy.

Methods

A systematic literature search was done in health-related electronic databases. The search was limited to studies published in English until September 2017. We also checked the references of retrieved articles and relevant reviews for any additional studies. The methodological quality of the studies included in this review was assessed using the 'Scales for Quality Assessment'. The I ² test was used to quantify between-study heterogeneity. A value of I ² > 50% indicated substantial heterogeneity. For the pooled analysis, summary odds ratio (OR) and its 95% confidence interval (CI) in random effect model were used.

Results

Eight case-control studies (1192 cases with diabetic nephropathy and 2399 controls) met the inclusion criteria. Three groups of people namely Africans, Asians and Caucasians were included in this review. There were significant protective effects of SNP -819 C/T in overall population (OR 0.32, 95% CI 0.26-0.4) and - 1082 A/G SNP in the Asian population (OR 0.64, 95% CI 0.47-0.86) on diabetic nephropathy in the recessive model. There was no significant effect of -592 A/C on diabetic nephropathy.

Conclusion

The findings suggest the protective effects of -1082A/G and -819G/A polymorphisms on the risk of developing diabetic nephropathy in type 2 diabetes mellitus, especially in the Asian population. Well- designed, prospective studies with sufficient number of participants are recommended to substantiate these findings.

Nutrigenetic variants and cardio-metabolic risk in women with or without gestational diabetes

AIM

Gestational diabetes mellitus (GDM) is the most frequent metabolic disorder in pregnancy and it can be considered a silent risk associated to T2DM and CVD later in life. The aim of this study was to investigate the association of clinical parameters with nine single nucleotide polymorphisms (SNPs) involved with nutrients and metabolism in women with or without GDM in order to identify potential routine clinical markers for early prevention.

METHODS

Nine gene variants associated with nutrients and metabolism, namely PPARG2 rs1801282 (C > G); PPARGC1A rs8192678 (C > T); TCF7L2 rs7903146 (C > T); LDLR rs2228671 (C > T); MTHFR rs1801133 (C > T); APOA5 rs662799 (T > C); GCKR rs1260326 (C > T); FTO rs9939609 (T > A); MC4R rs17782313 (T > C) were genotyped in 104 GDM cases and 124 controls using High Resolution Melting (HRM) analysis.

RESULTS

The genetic variant rs7903146 (C > T) in TCF7L2 gene showed a strong association with GDM risk (OR: 2.56; 95% CI: [1.24-5.29]). Moreover, a significant correlation was observed between lipid parameters and polymorphisms in other genes, namely PPARG2 [p = 0,03], APOA5 [p = 0,02], MC4R [p = 0,03], LDLR [p = 0,04] and FTO [p = 0,03]. In addition, rs17782313 variant, mapped close to MC4R gene, was associated to BMI in pre-pregnancy [p = 0,02] and at the end of pregnancy [p = 0,03] in GDM group.

CONCLUSION

In our study, we found significant associations between routine clinical parameters and some gene variants connected with nutrients and metabolism in women with GDM. These results can provide useful information to develop effective tools and possible personalized intervention strategies in a timely manner.

Genome-wide DNA methylation variation in maternal and cord blood of gestational diabetes population

AIMS

Gestational diabetes mellitus (GDM) has always been a concerning issue for pregnant women. In recent studies, GDM was found to be related to epigenetic modifications, which would alter gene expressions, thus affecting the patients' and their offspring's health, leading to a higher probability of developing metabolic syndromes and diabetes later in life.

METHODS

In this study, we collected both maternal and cord blood samples from 16 pregnant women and their newborns, including eight exposed to GDM. GDM was diagnosed via a 75g oral glucose tolerance test (OGTT) at 24-28weeks of pregnancy. DNA methylation was measured at 841,573 CpG sites via the Infinium HumanMethylationEPIC BeadChip. An Ingenuity Pathway Analysis was conducted afterwards to identify genes and pathways epigenetically affected by GDM.

RESULTS

We identified the top 200 loci and their corresponding genes in the maternal blood group (n=151) and cord blood group (n=167), both of which were methylated differently in the GDM and unexposed group. Metabolic disease-related pathways and molecules, such as interleukin-6 and interleukin-10 were identified in both groups. These results suggested that GDM has epigenetic effects on both mother and their offspring, which might result in future metabolic syndromes or diabetes.

CONCLUSIONS

The high-throughput platform enabled us to analyze methylation sites throughout the genome and identify the most promising genes and pathways associated with GDM.

Altered cytokine network in gestational diabetes mellitus affects maternal insulin and placental-fetal development

Pregnancy is characterized by an altered inflammatory profile, compared to the non-pregnant state with an adequate balance between pro-and anti-inflammatory cytokines needed for normal development. Cytokines are small secreted proteins expressed mainly in immunocompetent cells in the reproductive system. From early developmental stages onward, the secretory activity of placenta cells clearly contributes to increase local as well as systemic levels of cytokines. The placental production of cytokines may affect mother and fetus independently. In turn because of this unique position at the maternal fetal interface, the placenta is also exposed to the regulatory influence of cytokines from maternal and fetal circulations, and hence, may be affected by changes in any of these. Gestational diabetes mellitus (GDM) is associated with an overall alteration of the cytokine network. This review discusses the changes that occur in cytokines post GDM and their negative effects on maternal insulin and placental-fetal development.

Genetic variants associated with gestational diabetes mellitus: a meta-analysis and subgroup analysis

Previous studies have demonstrated that gestational diabetes mellitus (GDM) and Type 2 diabetes mellitus (T2D) share common genetic polymorphisms. We conducted meta-analysis and subgroup analysis of all available variants and determined the effects of confounding and experimental components on the genetic association of GDM. Any case-controlled or cohort studies with genotype distribution compared GDM cases with controls were included. In total, 28 articles including 8,204 cases and 15,221 controls for 6 polymorphisms were studied. rs10830963(MTNR1B), rs7903146(TCF7L2), and rs1801278(IRS1) were significantly associated with the increased GDM risk. The association of rs4402960(IGF2BP2) and rs1800629(TNF-α) was significant only when the studies with control allele frequency deviation and publication bias were excluded. Further subgroup analysis showed the risk alleles of rs7903146(TCF7L2) and rs1801282(PPARG) were significantly associated with the GDM risk only in Asian, but not in Caucasian population. The OGTT test using 100 g, but not 75 g; and genotype detection by other assays, but not Taqman method, were also significantly associated with increased GDM risk in rs1801278(IRS1) and rs7903146(TCF7L2). Overall GDM was associated with rs10830963(MTNR1B), rs7903146(TCF7L2), and rs1801278(IRS1), but only rs7903146(TCF7L2) and rs1801282(PPARG) were significant in Asian populations. While rs1801278(IRS1) and rs7903146(TCF7L2) were significantly affected by OGTT protocol and genotyping methods.

Impact of Systemic Inflammation on the Progression of Gestational Diabetes Mellitus

With increasing rates of obesity and new diagnostic criteria for gestational diabetes mellitus (GDM), the overall prevalence of GDM is increasing worldwide. Women with GDM have an increased risk of maternal and fetal complications during pregnancy as well as long-term risks including higher prevalence of type 2 diabetes mellitus and cardiovascular disease. In recent years, the role of immune activation and inflammation in the pathogenesis of GDM has gained increasing attention. This monograph explores the current state of the literature as regards the expression of markers of inflammation in the maternal circulation, placenta, and adipose tissue of women with GDM.

Changes in the TNF-alpha/IL-10 ratio in hyperglycemia-associated pregnancies

AIMS

TNF-α is a diabetogenic cytokine associated with adverse outcomes during pregnancy that can be counterbalanced by IL-10. We have investigated IL-10 and TNF-α balance at maternal and placental levels in hyperglycemia-associated pregnancies.

METHODS

One hundred and ninety-two pregnant women participated, which included normoglycemic women (ND) and women with mild gestational hyperglycemia (MGH), gestational diabetes mellitus (GDM) and type 2 diabetes mellitus (DM2). Maternal plasma and placental tissue IL-10 and TNF-α levels were measured by ELISA and placental TNF-α was also immunolocalized.

RESULTS

Maternal plasma TNF-α levels were highest in GDM (p=0.0190), whereas TNF-α levels were highest in placental tissues in DM2 (p=0.0095). Immunohistochemistry also showed strong reactivity with anti-TNF-α antibody in the villous structures in the DM2 group. Conversely, IL-10 levels were lowest in maternal plasma of the DM2 group (p=0.0228). The TNF-α/IL-10 ratio in maternal plasma progressively increased with the severity of hyperglycemia (p<0.0001), being highest in placenta of the DM2 group (p=0.0150). In both, plasma and placenta, TNF-α/IL-10 ratio were correlated with mean maternal glycemia and HbA1c levels.

CONCLUSIONS

Alterations of placenta and serum TNF-α/IL-10 balance with predominance of TNF-α were correlated with the severity of hyperglycemia during gestation. This association may offer insight into the pathogenesis of gestational hyperglycemia and associated pregnancy outcomes.

Investigation of Calpain 10 (rs2975760) gene polymorphism in Asian Indians with Gestational Diabetes Mellitus

Background

Type 2 Diabetes Mellitus (T2DM) and Gestational Diabetes Mellitus (GDM) are part of a heterogeneous and complex metabolic group of disorders that share common pathophysiological circumstances, including β-cell dysfunction and insulin resistance. The protein Calpain 10 (CAPN10) plays a role in glucose metabolism, pancreatic β-cell insulin secretion, and thermogenesis.

Objective

Polymerase Chain Reaction–Restriction Fragment Length Polymorphism (PCR–RFLP) based genotyping of CAPN10 (rs2975760) polymorphism was carried out in T2DM and GDM with suitable controls for each of the pathologies from the same population. Genomic DNA was isolated from 787 participants, including 250 cases of T2DM, 287 pregnant women, of which 137 were identified as having GDM and the remaining 150 were confirmed as non-GDM, and 250 healthy control volunteers, and association analysis was carried out for genotypes and alleles.

Results

In the present study, T2DM was compared with healthy controls and was not found to be associated with the CAPN10 C allele (odds ratio, OR: 1.09; 95% CI = 0.8011–1.484; p = 0.5821). GDM also did not show any association when compared with non-GDM (OR: 1.124; 95% CI = 0.7585–1.667; p = 0.5606) respectively.

Conclusion

Our study suggests that the CAPN10 (rs2975760) polymorphism scrutinized in this study is not associated with T2DM and GDM.

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In this study Calpain 10 (CAPN10) gene was carried out with Type 2 Diabetes Mellitus (T2DM) and Gestational Diabetes Mellitus (GDM). T2DM and GDM are different etiologies of the same complex diseases, frequently coexisting disorders and major components of metabolic syndrome that cause a substantial public health and economic burden worldwide.

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In this study T2DM, GDM are subsequently studied with rs2975760 polymorphism in CAPN10 gene.

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Molecular Analysis were performed by PCR-RFLP analysis.

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A total of 787 samples were included.

Genetic variants and the risk of gestational diabetes mellitus: a systematic review

BACKGROUND

Several studies have examined associations between genetic variants and the risk of gestational diabetes mellitus (GDM). However, inferences from these studies were often hindered by limited statistical power and conflicting results. We aimed to systematically review and quantitatively summarize the association of commonly studied single nucleotide polymorphisms (SNPs) with GDM risk and to identify important gaps that remain for consideration in future studies.

METHODS

Genetic association studies of GDM published through 1 October 2012 were searched using the HuGE Navigator and PubMed databases. A SNP was included if the SNP-GDM associations were assessed in three or more independent studies. Two reviewers independently evaluated the eligibility for inclusion and extracted the data. The allele-specific odds ratios (ORs) and 95% confidence intervals (CIs) were pooled using random effects models accounting for heterogeneity.

RESULTS

Overall, 29 eligible articles capturing associations of 12 SNPs from 10 genes were included for the systematic review. The minor alleles of rs7903146 (TCF7L2), rs12255372 (TCF7L2), rs1799884 (-30G/A, GCK), rs5219 (E23K, KCNJ11), rs7754840 (CDKAL1), rs4402960 (IGF2BP2), rs10830963 (MTNR1B), rs1387153 (MTNR1B) and rs1801278 (Gly972Arg, IRS1) were significantly associated with a higher risk of GDM. Among them, genetic variants in TCF7L2 showed the strongest association with GDM risk, with ORs (95% CIs) of 1.44 (1.29-1.60, P < 0.001) per T allele of rs7903146 and 1.46 (1.15-1.84, P = 0.002) per T allele of rs12255372.

CONCLUSIONS

In this systematic review, we found significant associations of GDM risk with nine SNPs in seven genes, most of which have been related to the regulation of insulin secretion.

Cytokine levels in gestational diabetes mellitus: a systematic review of the literature

PROBLEM

Gestational diabetes mellitus (GDM) is an inflammatory condition that involves unbalanced cytokine production. We carried out a systematic review on the relationship between GDM and maternal circulating levels of cytokines in the 2nd/3rd trimesters.

METHOD OF STUDY

Three electronic databases (MEDLINE, EMBASE and LILACS), were searched. Duplicate study selection, extraction and quality assessment was performed.

RESULTS

Twenty-two studies with 1982 participants reporting levels of 9 cytokines (IL-1B, IL-2, IL-6, IL-10, IL-13, IL-18, IFN-G, TGF-B and TNF-A) were included. Most studies differed considerably in selection criteria, sampling and assay methods and in reporting their results. Consequently, only two studies could be pooled: TNF-A concentration was slightly higher in GDM than in control patients, although not significant (WMD=0.45, 95% CI -0.34-1.23).

CONCLUSIONS

New studies with well-defined, more homogeneous methodological parameters are needed to detect whether there are significant differences in circulating levels of cytokines in patients with GDM.

Influence of maternal hyperglycemia on IL-10 and TNF-α production: the relationship with perinatal outcomes

AIMS

This study was conducted to evaluate maternal and placental concentrations of interleukin 10 (IL-10) and tumor necrosis factor-alpha (TNF-α) in pregnant women with glycemic mean (GM) < or ≥100 mg/dL, as well as correlate IL-10 and TNF-α placental concentrations with perinatal outcomes.

METHODS

One hundred eighty-six pregnant women were distributed in groups determined by a GM <100 mg/dL or a GM ≥100 mg/dL. The GM, HbA1c levels, maternal and placental concentrations of IL-10 and TNF-α, and the correlation of placental cytokines with perinatal outcomes were evaluated.

RESULTS

In maternal blood, the lowest concentrations of IL-10 (p = 0.0019) and TNF-α (p = 0.0185) were observed in the GM ≥100-mg/dL group. The placentas from GM ≥100 mg/dL group exhibited higher TNF-α concentrations (p = 0.0385). Placental IL-10 directly correlated with hemoglobin (r = 0.63; p = 0.02) and insulin (r = 0.78; p = 0.01) levels in the umbilical cord and with 1-min (r = 0.53; p = 0.0095) and 5-min (r = 0.69; p = 0.0003) Apgar scores. Placental TNF-α displayed a tendency to inversely correlate with fetal weight (r = -0.41; p = 0.05).

CONCLUSION

Compared to GM <100 mg/dL, GM ≥100 mg/dL was associated with a reduction in maternal IL-10 and TNF-α concentrations and increased placental TNF-α production. Placental IL-10 production was similar in both groups studied and directly correlated with hemoglobin and umbilical cord insulin levels, as well as with the 1- and 5-min Apgar scores.

Inflammatory mediator gene polymorphisms and gestational diabetes: a review of the literature

The incidence of gestational diabetes (GD) is rising worldwide, in parallel with obesity and type 2 diabetes. Obesity and GD are conditions that have in common a state of chronic, low-grade subclinical inflammation characterized by abnormal production of cytokines and mediators. Genetic polymorphisms may influence the production of inflammatory mediators and predispose to different disorders, including diabetes. The aim of this study was to review the existing literature on the relationship between inflammatory mediator gene polymorphisms and GD. The search in PubMed was restricted to articles published in English, from January 1990 to December 2010. Eight studies were included. These publications evaluated 13 different SNPs and six inflammatory mediators in the blood of women with GD. Gene polymorphisms related to leptin, mannose-binding lectin (MBL) and RAGE (receptor for advanced glycation end products) were individually evaluated in a single study each. Leptin and MBL plasma levels were also evaluated in two studies. The participants included in the studies were ethnically different, but matched with controls. Different criteria were adopted to select the participants. Seven of the eight studies included took into consideration the BMI of patients and controls. Due to the heterogeneity and limited number of studies on GD and inflammatory gene polymorphisms, we could not pool together any of the results or perform any additional analyses of the existing data. Since the existing findings come from isolated studies with mostly small sample sizes, there is a need for new, larger, properly designed studies of good methodological quality.

Profile of inflammatory mediators in gestational diabetes mellitus: phenotype and genotype

PROBLEM

Our study aimed to assess in vitro production of IL-10, IL-6, TNF-A, and adiponectin serum levels in pregnant women with and without gestational diabetes mellitus (GDM) and to investigate a possible association between GDM and IL-10-1082 A>G (rs1800896), IL-6-174 G>C (rs1800795), TNF-A-308 G>A (rs1800629), adiponectin +45 T>G (rs2241766), and adiponectin-11377 C>G (rs266729) gene polymorphisms.

METHOD OF STUDY

This case-control study included 79 women with GDM and 169 healthy controls (C) grouped according to pre-pregnancy BMI. IL-10, IL-6, and TNF-A culture supernatant and adiponectin serum levels were assessed by ELISA. DNA genotype was performed by PCR-RFLP.

RESULTS

Adiponectin levels were significantly higher in C than GDM women, even within the same BMI category. Cytokines levels were similar between the groups. There were no associations between GDM and the analyzed gene polymorphisms.

CONCLUSIONS

Women with GDM have significantly lower adiponectin levels in the third trimester, regardless of BMI.