Disorders Of Glucose Homeostasis Research Articles

The Effect of Selenium, Zinc, and their Combined Supplementation on Cardiometabolic Biomarkers-comparing their Effects in the Energy Restriction and High-fat Diet Methods in Obese Rats.

The fat distribution in the body determines the risk of cardiometabolic problems such as heart disease and diabetes. Some dietary supplements, such as selenium and zinc, possess lipolytic and anti-angiogenic functions, which may be a useful strategy in reducing the risk of cardiometabolic complications. This study evaluated the effect of zinc (Zn), selenium (Se), and their combined supplementation on cardiometabolic risk factors in male Wistar rats in two nutritional models, including caloric restriction (CR) and high-fat diet (HFD). The 48 male Wistar rats were divided into three diet groups (HFD and CR and normal diet (ND)). The HFD group was subdivided into four groups (N=8 rats in each group) that received (HFD+Se), (HFD+Zn), (HFD+Zn+Se), and HFD alone as the control group, respectively. After 8 weeks of intervention, biochemical tests were performed on serum levels, including measurement of lipid profile (triglyceride, Cholesterol, LDL and HDL) and glycemic indices (fasting blood sugar, insulin and insulin sensitivity markers). The results showed that supplementation significantly improved the lipid profile (P <0.001). A comparison of glucose homeostasis indices in the study groups also showed a significant difference. The serum level of glucose was higher in the HFD group than in the intervention groups (P <0.001). Also, the rate of improvement of lipid profile and glycemic indexes in the group receiving the combination of two supplements showed a better trend than those receiving zinc and selenium alone. However, the values were statistically significant only for glucose homeostasis indices (P <0.001). Although obesity is a multifactorial condition, controlling other risk factors, zinc and selenium and their combined supplementation can lead to promising solutions for the treatment of obesity-induced glucose and lipid homeostasis disorders.

Sirtuin Expression in Insulin-Sensitive Tissues of Rats with Impaired Glucose Tolerance is not Affected by Resistance Training or Zinc Supplementation.

While physical activity and zinc supplementation have shown benefits in diabetes management, little is known about their effect on less severe glucose homeostasis disorders, such as impaired glucose tolerance. On the other hand, sirtuins have an important role in glucose metabolism and insulin sensitivity, but to date, there is no information about the impact of zinc supplementation or physical activity on their regulation in individuals with impaired glucose homeostasis. The aim of this study was to assess the effect of supplemental zinc, muscle-resistance training, and their combination on the expression of selected sirtuins in insulin-sensitive tissues of rats with impaired glucose tolerance. Thirty male Wistar rats with impaired glucose tolerance were fed a high-fat diet for 12 weeks while subjected to zinc supplementation, resistance training, both, or none. Morphometric and metabolic evaluations were performed at the end of the experimental period, and gene expression of sirtuins 1, 2, 4, and 7 was assessed in liver, gastrocnemius muscle, and white adipose tissue. Results showed that zinc supplementation and/or resistance training did not improve metabolic parameters of rats with impaired glucose tolerance, nor did they affect the expression of selected sirtuins in any of the tissues evaluated. However, the expression of some sirtuins was associated with metabolic parameters in a tissue-specific manner. Additional studies are needed to evaluate whether zinc supplementation and/or resistance training can improve metabolic status or modulate sirtuins expression in advanced stages of impaired glucose homeostasis.

Patterns of Endocrine Disorders in a Neonatal Intensive Care Unit: A Single-Center Retrospective and Descriptive Study

Background: Endocrine disorders in infants in neonatal intensive care units (NICU) represent a significant clinical concern. Understanding the frequency and variety of these disorders is crucial for effective patient management. Objectives: This single-center retrospective study was conducted to examine the frequency and patterns of endocrine disorders among neonates in the NICU. Methods: We performed a retrospective review of 1 845 patient records over five years from the NICU at Çanakkale Onsekiz Mart University Health Practice and Research Hospital. The study included patients admitted between January 1, 2016, and March 31, 2021, who were diagnosed with endocrine disorders according to the international classification of diseases (ICD). Diagnostic criteria were used to identify and categorize endocrine disorders, primarily focusing on hypoglycemia, congenital hypothyroidism, hypothyroxinemia of prematurity, neonatal hyperthyrotropinemia (HTT), and disorders of calcium and magnesium metabolism. Data analysis was conducted using descriptive statistics. Results: Endocrine disorders were identified in 14.6% (CI: 13.15 - 16.38) of the neonates. The most prevalent were thyroid disorders (5.15%, CI: 4.23 - 6.25), disorders of calcium metabolism (3.68%, CI: 2.92 - 4.64), and disorders of glucose homeostasis (3.63%, CI: 2.87 - 4.58). Notably, neonatal HTT was more frequent than previously reported. The majority of endocrine issues occurred in premature infants. Hypoglycemia was the most frequent glucose homeostasis disorder, affecting 24.7% (CI: 19.9 - 30.2) of those diagnosed with endocrine issues. Among the cases with calcium metabolism disorders, hypocalcemia was predominant (79.4%, CI: 68.3 - 87.3), with the majority (89%, CI: 80.1 - 95.9) being classified as early neonatal hypocalcemia. Conclusions: Endocrine disorders, particularly those related to thyroid, calcium, and glucose homeostasis, remain prevalent issues in the NICU. Prematurity significantly contributes to these complications. The frequency and variety of endocrine disorders are likely to evolve with improvements in laboratory techniques and diagnostic methods. Future larger-scale studies could provide more comprehensive insights into these disorders.

Clinical investigation of glucokinase activators for the restoration of glucose homeostasis in diabetes.

As a sensor, glucokinase (GK) controls glucose homeostasis, which progressively declines in patients with diabetes. GK maintains the equilibrium of glucose levels and regulates the homeostatic system set points. Endocrine and hepatic cells can both respond to glucose cooperatively when GK is activated. GK has been under study as a therapeutic target for decades due to the possibility that cellular GK expression and function can be recovered, hence restoring glucose homeostasis in patients with type 2 diabetes. Five therapeutic compounds targeting GK are being investigated globally at the moment. They all have distinctive molecular structures and have been clinically shown to have strong antihyperglycemia effects. The mechanics, classification, and clinical development of GK activators are illustrated in this review. With the recent approval and marketing of the first GK activator (GKA), dorzagliatin, GKA's critical role in treating glucose homeostasis disorder and its long-term benefits in diabetes will eventually become clear.

Metabolic effects of aldosterone

Currently, increasing evidence shows the mutual influence of aldosterone and adipose tissue. Aldosterone excess has been reported in patients with obesity and metabolic syndrome. Aldosterone has a direct effect on adipose tissue increasing anabolic activity and expression of mineralocorticoid receptors. In turn, excessive activation of MCR leads to stimulation of adipogenesis and an increase in the volume of adipose tissue. Aldosterone excess can be considered an independent cardiovascular risk factor that affects such processes as cardiac fibrosis, nephrosclerosis, and arteriosclerosis. There is convincing evidence of higher prevalence and severity of impaired glucose homeostasis and lipid metabolism disorders among patients with primary hyperaldosteronism. Similar pathological changes are also observed in patients with obesity and metabolic syndrome. This review presents scientific data on the metabolic effects of aldosterone, in particular its effect on adipose tissue function, glucose and lipid metabolism. Treatment with mineralocorticoid receptor antagonists may provide substantial benefit in the management of metabolic syndrome, contribute to the stabilisation of glucose and lipid metabolism, improve clinical status of patients with cardiovascular diseases and reduce the risk of complications. However, available evidence from the conducted studies is not sufficient to justify introduction of such therapy into clinical practice.

Association of urinary arsenic metabolism with type 2 diabetes and glucose homeostasis: Cross-sectional and longitudinal associations.

BackgroundPrevious researches have assessed the relationships of urinary arsenic metabolism with type 2 diabetes (T2D) and glucose-insulin homeostasis, but the results were controversial, and potential mechanisms remain largely unclear. ObjectivesThis study aimed to investigate the cross-sectional and longitudinal associations of urinary arsenic metabolism with T2D prevalence and glucose changes in relatively higher arsenic exposure, and further to evaluate the underlying roles of oxidative damage in these relationships. MethodsWe included 796 participants at baseline, among them 509 participants were followed up after 2 years. Logistic regression model and leave-one-out approach were applied to evaluate the associations of arsenic metabolism with T2D prevalence. Linear mixed model was conducted to estimate the relationship of arsenic metabolism with glycemic changes over two years. The associations between arsenic metabolism and indicators of oxidative stress were assessed with a linear regression model. We further performed mediation analysis to investigate the role of oxidative stress in the associations of arsenic metabolism with 2-year change of glucose levels. ResultsHigher urinary MMA% increased T2D prevalence and baseline glucose levels. MMA% was positively associated with 2-year change of glucose levels. Moreover, we observed significant dose-response relationship between MMA% and 8-hydroxy-2-deoxyguanosine (8-OHdG). However, the mediating role of 8-OHdG in the association of MMA% and 2-year change of glucose levels was not observed in this population. ConclusionsIn this population exposure to relatively higher arsenic levels, higher MMA% contributed to increased T2D prevalence and glucose homeostasis disorder. Arsenic metabolism also affected oxidative stress levels, especially 8-OHdG. Further studies are required to investigate the potential mechanisms.

The glycemic profile in patients with non-alcoholic steatohepatitis and type 2 diabetes depending on diabetic kidney disease

Background. State of carbohydrate metabolism and severity of insulin resistance in the comorbid course of non-alcoholic steatohepatitis (NASH) and diabetic kidney disease (DKD) in patients with type 2 diabetes mellitus (DM2) is due to the cascade of possible transformation of NASH into liver cirrhosis. The purpose is to study the interaction of changes in glucose and insulin homeostasis, the degree of insulin resistance and insulin sensitivity, the degree of hemoglobin glycosylation on the clinical course of NASH associated with DM depending on the presence of DKD and its stage. Materials and methods. One hundred and eight patients with NASH and comorbid DM2 were examined. The average age of patients was 58.2 ± 6.1 years. There were 63 women (58.3 %) and 45 men (41.7 %). Depending on the presence of DKD, 4 groups of patients were formed, who were randomized by age, sex, activity of cytolytic syndrome. The comparison group consisted of 30 healthy individuals of the appropriate age and sex. The degree of hepatic steatosis and its nature were determined using SteatoTest, ASH and NASH-Test kits (BioPredictive, France). The stage of liver fibrosis was determined using FibroTest (BioPredictive, France), a set of markers for quantitative biochemical evaluation of fibrosis. Results. In patients with NASH, DM2 and DKD stage I–II, we found a significant decrease in serum albumin by 9.0 % (p &lt; 0.05); glomerular filtration rate (GFR) and urine albumin, on the contrary, increased significantly, by 1.5 times (p &lt; 0.05) compared to those in the control group, which indicates the phenomenon of hyperfiltration and is specific to the initial stage of DKD. When NASH is combined with DM2 and DKD stage III, a significant decrease in serum albumin by 1.2 times (p &lt; 0.05) is reported; GFR and albuminuria were significantly increased, by 1.4 and 11.7 times (p &lt; 0.05), respectively, compared to the control group. In patients with NASH, DM2 and DKD stage IV, we found a significant decrease in serum albumin by 1.4 times (p &lt; 0.05), it was significantly increased by 30.2 times (p &lt; 0.05) compared to the indicator in the control group, and the GFR, on the contrary, was significantly reduced by 1.7 times (p &lt; 0.05), which indicates the progression of DKD. Conclusions. Disorders of glucose homeostasis due to insulin resistance are one of the probable risk factors for the progression of non-alcoholic steatohepatitis and type 2 diabetes mellitus in the presence of stage I–IV diabetic kidney disease.

An overview of the outreach of the 2019-2021 Endo-ERN knowledge generation webinars.

The current study aims to assess the development of the knowledge generation program of the European Reference Network on Rare Endocrine Conditions (Endo-ERN) from its start in 2019 until December 2021, with special reference to webinars. We analyzed the number of webinars and live/postevent participants and whether participation and engagement of the attendees changed over time. A total of 30 (86%) self-prepared webinars comprising 300 h of knowledge and competence sharing were broadcasted (2019 - 3; 2020 - 13; 2021 - 14). A total of six webinars were broadcasted live prior to the coronavirus disease 2019 pandemic (https://endo-ern.eu/events/webinars/). The most active main thematic group (MTG) was MTG3 Genetic Disorders of Glucose and Insulin Homeostasis with eight (27%) webinars. Two (25%) MTGs fulfilled the goal to prepare at least two to three webinars per year. Patients were actively involved in 20% of the accounted webinars as both creators and presenters. The total number of live and postevent participants was 3023. The availability of the webinars after the live broadcast increased their outreach with a larger number of postevent viewers (n = 1629, 54%). Within the formal structured evaluation of the webinars, 40-85% of the participants replied on separate occasions and helped improve content. The free webinar access is among the perceived reasons for the rapidly increasing number of total hits to the Endo-ERN website. In conclusion, for its short existence, the Endo-ERN rapidly developed educational outreach, and further efforts to attract creators and learners are warranted.

Comment: Amenable Treatable Severe Pediatric Epilepsies

Phillip L. Pearl Seminars in Pediatric Neurology Volume 23, Issue 2, May 2016, Pages 158-166 Vitamin-dependent epilepsies and multiple metabolic epilepsies are amenable to treatment that markedly improves the disease course. Knowledge of these amenably treatable severe pediatric epilepsies allows for early identification, testing, and treatment. These disorders present with various phenotypes, including early onset epileptic encephalopathy (refractory neonatal seizures, early myoclonic encephalopathy, and early infantile epileptic encephalop athy), infantile spasms, or mixed generalized seizure types in infancy, childhood, or even adolescence and adulthood. The disorders are presented as vitamin responsive epilepsies such as pyridoxine, pyridoxal-5-phosphate, folinic acid, and biotin; transportopathies like GLUT-1, cerebral folate deficiency, and biotin thiamine responsive disorder; amino and organic acidopathies including serine synthesis defects, creatine synthesis disorders, molybdenum cofactor deficiency, and cobalamin deficiencies; mitochondrial disorders; urea cycle disorders; neurotransmitter defects; and disorders of glucose homeostasis. In each case, targeted intervention directed toward the underlying metabolic pathophysiology affords for the opportunity to significantly effect the outcome and prognosis of an otherwise severe pediatric epilepsy.

Longan extract suppresses food intake through regulation of POMC/AgRP neuronal activities and endoplasmic reticulum stress in hypothalamus of db/db mice.

Type 2 diabetes mellitus (T2DM) is one of the biggest public health issues worldwide and closely related to development of other chronic diseases such as cardiovascular diseases, cancer and neurodegenerative diseases. Considerable percentage of T2DM patients undergo have suffered from binge eating disorder which exacerbates insulin resistance and metabolic challenges. Longan (Dimocarpus longan L.) and its constituents are reported for their various health benefits. However, it is still unknown whether longan fruit supplementation can ameliorate glucose homeostasis and binge eating disorder found in T2DM. The current study aimed to investigate whether longan fruit extract (LE) supplementation can improve diabetic hyperglycemia through modulation of feeding center located in hypothalamus of db/db T2DM mice. As a result, LE supplementation ameliorated fasting blood glucose levels and reduced excessive epididymal fat accumulation. In addition, LE administration improved glucose tolerance and insulin sensitivity in db/db mice. Especially, LE supplemented mice showed less food consumption which was in line with increase of pro-opiomelanocortin (POMC) neuronal activities and decrease of agouti-related peptide (AgRP) neuronal activities. Furthermore, LE supplementation reduced hypothalamic endoplasmic reticulum (ER) stress which was stimulated in db/db mice. As ER stress is a crucial factor involving in appetite control and glucose homeostasis, the effect of LE supplementation on circulating glucose levels and feeding behavior might be mediated by suppression of hypothalamic ER stress. Collectively, these findings suggest that LE could be a potential nutraceutical for improvement of T2DM as well as patients with satiety issues.

The potential effect of metformin on fibroblast growth factor 21 in type 2 diabetes mellitus (T2DM).

Fibroblast growth factor 21 (FGF21) is a peptide hormone mainly synthesized and released from the liver. FGF21 acts on FGF21 receptors(FGFRs) and β-Klotho, which is a transmembrane co-receptor. In type 2 diabetes mellitus (T2DM), inflammatory disorders stimulate the release of FGF21 to overcome insulin resistance (IR). FGF21 improves insulin sensitivity and glucose homeostasis. Metformin which is used in the management of T2DM may increase FGF21 expression. Accordingly, the objective of this review was to clarify the metformin effect on FGF21 in T2DM. FGF21 level and expression of FGF2Rs are dysregulated in T2DM due to the development of FGF21 resistance. Metformin stimulates the hepatic expression of FGF21/FGF2Rs by different signaling pathways. Besides, metformin improves the expression of β-Klotho which improves FGF21 sensitivity. In conclusion, metformin advances FGF21 signaling and decreases FGF21 resistance in T2DM, and this might be an innovative mechanism for metformin in the enhancement of glucose homeostasis and metabolic disorders in T2DM patients.

Higher β cell death in pregnant women, measured by DNA methylation patterns of cell-free DNA, compared to new-onset type 1 and type 2 diabetes subjects: a cross-sectional study

Diabetes is a metabolic disorder of glucose homeostasis in which β cell destruction occurs silently and is detected mainly when symptoms appear. In the last few years, it has emerged a great interest in developing markers capable of detecting pancreatic β cell death focused on improving early diagnosis and getting a better treatment response, mainly in type 1 diabetes. But other types of diabetes would also benefit from early detection of β cell death. Differentially methylated circulating DNA is being studied as minimally invasive biomarker of cell death. We aimed to explore whether the unmethylated/methylated ratio of the insulin and amylin genes might be a good biomarker of β cell death in different types of diabetes. A lower index ∆Ct indicates a higher rate of β-cell death. Plasma samples from subjects without diabetes, pregnant women, pregnant with gestational diabetes (GDM), type 1 diabetes and type 2 diabetes were analyzed. A qPCR reaction with specific primers for both methylated and unmethylated fragments of insulin and amylin genes were carried out. Pregnant women, GDM and non- GDM, showed a higher β-cell death for both markers (∆INS = 3.8 ± 2.1 and ∆Amylin = 8.5 ± 3.6), whereas T1D presented lower rate (∆INS = 6.2 ± 2.1 and ∆Amylin = 10.7 ± 2.9) comparable to healthy subjects. The insulin methylation index was associated with the newborn birth weight (r = 0.46; p = 0.033) and with insulin resistance (r = -0.533; p = 0.027) in the GDM group. The higher rate of β-cell death was observed in pregnant women independently of their metabolic status. These indexes could be a good indicator of β cell death in processes caused by defects on insulin secretion, insulin action, or both.

The effects of hormone replacement therapy: а window of opportunity for the cardiovascular system

Coronary artery disease and stroke make up the greater part of the pattern of cardiovascular diseases (CVD). Their prevalence is increasing primarily due to death rates decline and life expectancy increase. However, CVDs remain the leading cause of death in both high/middle and low income countries (WHO, 2008). The burden of coronary heart disease and stroke is determined both by a significant decrease in patients’ quality of life and the economic expenditures of healthcare aimed at treating these conditions and managing their complications. The overall CVD risk is more or less the same in men and women, but a detailed analysis shows a clear dependence on the patient age. The CVD risk in men is comparable to the CVD risk in women of younger age groups, i.e. CVD incidence rates in women are about ten years behind such rates in men. CVDs are of major concern for women who enter menopause. The changing endocrine profile predisposes to an increase in the cardiovascular event rates due to a combination of risk factors such as visceral obesity, atherogenic dyslipidemia, impaired glucose regulation, homeostasis disorders, and vascular dysfunction. However, an independent association between age-related degenerative changes in the ovaries and CVD risk has been established primarily in women with premature and early menopause (&lt;40– 45 years). Menopause hormone therapy (MHT) significantly reduces most CVD risks. The effectiveness of the prevention of irreversible effects of oestrogen deficiency is ensured by the timely MHT start during the very first pathological changes in female health or in the late stage of the menopausal transition/early postmenopausal stage (&gt;&lt;60 years or within ten years after the last menstrual period). The concept of prescribing MHT within the “window of therapeutic opportunity” produces a favourable benefit-risk ratio for patients.&gt;˂40– 45 years). Menopause hormone therapy (MHT) significantly reduces most CVD risks. The effectiveness of the prevention of irreversible effects of oestrogen deficiency is ensured by the timely MHT start during the very first pathological changes in female health or in the late stage of the menopausal transition/early postmenopausal stage (˂60 years or within ten years after the last menstrual period). The concept of prescribing MHT within the “window of therapeutic opportunity” produces a favourable benefit-risk ratio for patients.

Advances in natural small molecules on pretranslational regulation of gluconeogenesis.

Different tissues and organs coordinate to keep glucose levels at homeostasis. However, excessive gluconeogenesis in patients with type 2 diabetes mellitus increases blood glucose and causes dysregulation of homeostasis, which easily induces various diseases. Therefore, inhibiting excessive gluconeogenesis is a potential direction to regulate the disorder of blood glucose homeostasis and treat diabetes. The process of gluconeogenesis can be pretranslationally or posttranslationally regulated, and some natural small molecules can be involved in the pretranslational phase of gluconeogenesis, regulating glucose homeostasis by inhibiting gene expression, interfering with RNA transcription, and antagonizing related proteins. This paper will classify and review the natural small molecules with pretranslational regulation of gluconeogenesis according to the action sites and signaling pathways.

Antioxidant Enzyme Activity and Serum HSP70 Concentrations in Relation to Insulin Resistance and Lipid Profile in Lean and Overweight Young Men.

Oxidants are generated by all cells during normal oxidative respiration, and as long as they are under the control of appropriate mechanisms, they act as intracellular signaling molecules participating in complex functions. Oxidative stress can also affect insulin levels in the body. The production of reactive oxygen species by-products can lead to insulin resistance. Heat shock proteins (70 kDa) protect cells from the damaging effects of heat shock but also oxidative stress. The aim of the study was to investigate the serum concentration of HSP70 in young, non-obese but overweight men (BMI ≤ 30 kg/m2) and to assess its association with the insulin resistance, lipid profile and antioxidant system of red blood cells. Fifty-seven young men were examined and divided into two groups: lean men (n = 30) and men overweight (n = 27). A statistically significant difference was observed in the BMI (p < 0.007), HSP70 concentration (p < 0.000), serum insulin concentration (p < 0.000), HOMA-IR (p < 0.0001), superoxide dismutase (p < 0.02) and glutathione peroxidase (p < 0.05) between the studied groups. There was a negative correlation between the concentration of HSP70 with the insulin level (r = -0.50; p < 0.0004) and with the HOMA-IR (r = -0.50; p < 0.0004). These changes were associated with an increase in the activity of antioxidant enzymes. Our findings suggest that measuring the extracellular concentration of HSP70 can be an important indicator in disorders of glucose homeostasis.

A Flower-like Brain Targeted Selenium Nanocluster Lowers the Chlorogenic Acid Dose for Ameliorating Cognitive Impairment in APP/PS1 Mice.

Aβ aggregation-related neuroinflammation and imbalance of brain glucose homeostasis play important roles in the pathological process of Alzheimer's disease (AD). Chlorogenic acid (CGA) is one of the most common dietary polyphenols with neuroprotective effects. However, due to the low bioavailability of CGA, its application dose is usually high in vivo. In our previous study, the spherical selenium nanoparticles act as drug carriers to improve the bioactivity of resveratrol. Here, the brain-targeting peptide (TGN peptide) and CGA were used to prepare a new flowerlike selenium nanocluster (TGN-CGA@SeNCs) for enhancing the bioavailability of CGA. After decoration on selenium nanoclusters, the solubility and stability of CGA was obviously increased. Oral administration of a low dose of CGA (80 mg/kg/body weight) only slightly inhibited Aβ aggregate-related neuroinflammation and glucose homeostasis disorder in the brain. Moreover, CGA showed less effect on increasing the diversity and richness of gut microbiota. At the same concentration, the CGA-modified selenium nanocluster (CGA@SeNCs) and TGN-CGA@SeNCs showed better function in ameliorating the gut microbiota disorder. Especially, TGN-CGA@SeNCs significantly increased the relative abundance of Turicibacter, Colidextribacter, Ruminococcus, Alloprevotella, and Alistipes against oxidative stress, inflammation, and glucose homeostasis imbalance. Notably, only TGN-CGA@SeNCs can transport through the blood-brain barrier (BBB), and TGN-CGA@SeNCs showed better effects than CGA@SeNCs in regulating Aβ aggregation and improving brain glucose homeostasis. These results broadened the application of TGN-CGA@SeNCs, effectively improving the bioactivity of CGA, which also lowers the CGA dose for preventing AD progression.

The Role of Advanced Glycation End Products on Dyslipidemia.

Disorders of lipoprotein metabolism and glucose homeostasis are common consequences of insulin resistance and usually co-segregate in patients with metabolic syndrome and type 2 diabetes mellitus (DM). Insulin-resistant subjects are characterized by atherogenic dyslipidemia, a specific lipid pattern which includes hypertriglyceridemia, reduced high-density lipoprotein cholesterol level, and increased proportion of small, dense low-density lipoprotein (LDL). Chronic hyperglycemia favors the processes of non-enzymatic glycation, leading to the increased production of advanced glycation end products (AGEs). Apart from direct harmful effects, AGEs are also potent inducers of oxidative stress and inflammation. In addition, increased AGEs' production may induce further qualitative modifications of small, dense LDL particles, converting them to glycated LDLs. These particles are even more atherogenic and may confer an increased cardiovascular risk. In this narrative review, we summarize the available evidence of the pathophysiological role and clinical importance of circulating AGEs and glycated LDLs in patients with dyslipidemia, particularly those with DM and related complications. In addition, we discuss recent advances and the issues that should be improved regarding laboratory assessment of AGEs and glycated LDLs, as well as the possibilities for their therapeutic modulation.

Hepatic PTP4A1 ameliorates high-fat diet-induced hepatosteatosis and hyperglycemia by the activation of the CREBH/FGF21 axis.

Precise regulation of kinases and phosphatases is crucial for human metabolic homeostasis. This study aimed to investigate the roles and molecular mechanisms of protein tyrosine phosphatase type IVA1 (PTP4A1) in regulating hepatosteatosis and glucose homeostasis. Method: Ptp4a1-/- mice, adeno-associated virus encoding Ptp4a1 under liver-specific promoter, adenovirus encoding Fgf21, and primary hepatocytes were used to evaluate PTP4A1-mediated regulation in the hepatosteatosis and glucose homeostasis. Glucose tolerance test, insulin tolerance test, 2-deoxyglucose uptake assay, and hyperinsulinemic-euglycemic clamp were performed to estimate glucose homeostasis in mice. The staining, including oil red O, hematoxylin & eosin, and BODIPY, and biochemical analysis for hepatic triglycerides were performed to assess hepatic lipids. Luciferase reporter assays, immunoprecipitation, immunoblots, quantitative real-time polymerase chain reaction, and immunohistochemistry staining were conducted to explore the underlying mechanism. Results: Here, we found that deficiency of PTP4A1 aggravated glucose homeostasis and hepatosteatosis in mice fed a high-fat (HF) diet. Increased lipid accumulation in hepatocytes of Ptp4a1-/- mice reduced the level of glucose transporter 2 on the plasma membrane of hepatocytes leading to a diminution of glucose uptake. PTP4A1 prevented hepatosteatosis by activating the transcription factor cyclic adenosine monophosphate-responsive element-binding protein H (CREBH)/fibroblast growth factor 21 (FGF21) axis. Liver-specific PTP4A1 or systemic FGF21 overexpression in Ptp4a1-/- mice fed an HF diet restored the disorder of hepatosteatosis and glucose homeostasis. Finally, liver-specific PTP4A1 expression ameliorated an HF diet-induced hepatosteatosis and hyperglycemia in wild-type mice. Conclusions: Hepatic PTP4A1 is critical for regulating hepatosteatosis and glucose homeostasis by activating the CREBH/FGF21 axis. Our current study provides a novel function of PTP4A1 in metabolic disorders; hence, modulating PTP4A1 may be a potential therapeutic strategy against hepatosteatosis-related diseases.

Association of long-term air pollution exposure with the risk of prediabetes and diabetes: Systematic perspective from inflammatory mechanisms, glucose homeostasis pathway to preventive strategies

BackgroundLimited evidence suggests the association of air pollutants with a series of diabetic cascades including inflammatory pathways, glucose homeostasis disorder, and prediabetes and diabetes. Subclinical strategies for preventing such pollutants-induced effects remain unknown. MethodsWe conducted a cross-sectional study in two typically air-polluted Chinese cities in 2018–2020. One-year average PM1, PM2.5, PM10, SO2, NO2, and O3 were calculated according to participants' residence. GAM multinomial logistic regression was performed to investigate the association of air pollutants with diabetes status. GAM and quantile g-computation were respectively performed to investigate individual and joint effects of air pollutants on glucose homeostasis markers (glucose, insulin, HbA1c, HOMA-IR, HOMA-B and HOMA-S). Complement C3 and hsCRP were analyzed as potential mediators. The ABCS criteria and hemoglobin glycation index (HGI) were examined for their potential in preventive strategy. ResultsLong-term air pollutants exposure was associated with the risk of prediabetes [Prevalence ratio for O3 (PR_O3) = 1.96 (95% CI: 1.24, 3.03)] and diabetes [PR_PM1 = 1.18 (95% CI: 1.05, 1.32); PR_PM2.5 = 1.08 (95% CI: 1.00, 1.16); PR_O3 = 1.35 (95% CI: 1.03, 1.74)]. PM1, PM10, SO2 or O3 exposure was associated with glucose-homeostasis disorder. For example, O3 exposure was associated with increased levels of glucose [7.67% (95% CI: 1.75, 13.92)], insulin [19.98% (95% CI: 4.53, 37.72)], HOMA-IR [34.88% (95% CI: 13.81, 59.84)], and decreased levels of HOMA-S [-25.88% (95% CI: −37.46, −12.16)]. Complement C3 and hsCRP played mediating roles in these relationships with proportion mediated ranging from 6.95% to 60.64%. Participants with HGI ≤ −0.53 were protected from the adverse effects of air pollutants. ConclusionOur study provides comprehensive insights into air pollutant–associated diabetic cascade and suggests subclinical preventive strategies.

119-LB: Targeted IL-22 Improves Glucose Tolerance and Reduces Hepatic Steatosis and Hepatic Fibrosis in Murine Models of Diabetes and Liver Disease

The cytokine interleukin-22 (IL-22) is an inhibitor of cellular stress. In HFD murine models, systemic IL-22 is efficacious to restore glucose tolerance, reduce circulating triglycerides and hepatic steatosis, and improve AST:ALT ratio, but is also associated with gut and skin toxicity. As an approach to maintain efficacy without skin/gut adverse effects we have developed a prototype IL-22-based bispecific biologic drug candidate (IL-22-ScFv) which is targeted towards the pancreas and liver. In mouse models of T2D and NAFLD/NASH twice-weekly subcutaneous administration of IL-22-ScFv provides numerous therapeutic and metabolic benefits. After IL-22-ScFv administration for four weeks in HFD mice random glucose, glucose tolerance and insulin tolerance were normalised (c.f. chow fed controls) . Significant reduction in hepatic steatosis was also seen, evidenced by liver weight, histology, oil-red-O, and (normalisation of) key lipogenic gene expression patterns. In both Thioacetamide/HFD and Choline Deficient L-Amino acid defined/HFD mice IL-22-ScFv administration significantly reduced hepatic fibrosis (Masson’s trichrome, picrosirius red, and normalisation of hepatic expression of Col1a1&amp;2, Col3a1, Timp2, Mmp2 and Cd68) . Effective targeting of IL-22 to liver and pancreas was observed with minimal IL-22 exposure to gut and skin. Following four weeks administration of a range of doses of IL-22-ScFv no adverse effects were observed. Histological analysis of gut and skin showed no features of hyperproliferation, consistent with effective targeting of IL-22 to liver and pancreas. Mechanism of action of IL-22-ScFv was again shown to be reduction in cellular stress via IL-22 receptor mediated STAT3 phosphorylation. In conclusion, liver/pancreas targeted IL-22 shows promise as a therapeutic approach to metabolic liver disease, with concomitant improvement in disorders of glucose homeostasis. Disclosure J. B. Prins: None. H. Sajiir: None. S. Keshvari: None. K. Wong: None. J. Lockett: Advisory Panel; Lilly Diabetes. M. Mcguckin: None. S. Z. Hasnain: None.