Altered Glucose Metabolism Research Articles

Novel insights into the glucose metabolic alterations of freshwater snails: a pathway to molluscicide innovation and snail control strategies.

As ecosystem disruptors and intermediate hosts for various parasites, freshwater snails have significant socioeconomic impacts on human health, livestock production, and aquaculture. Although traditional molluscicides have been widely used to mitigate these effects, their environmental impact has encouraged research into alternative, biologically based strategies to create safer, more effective molluscicides and diminish the susceptibility of snails to parasites. This review focuses on alterations in glucose metabolism in snails under the multifaceted stressors of parasitic infections, drug exposure, and environmental changes and proposes a novel approach for snail management. Key enzymes within the glycolytic pathway, such as hexokinase and pyruvate kinase; tricarboxylic acid (TCA) cycle; and electron transport chains, such as succinate dehydrogenase and cytochrome c oxidase, are innovative targets for molluscicide development. These targets can affect both snails and parasites and provide an important direction for parasitic disease prevention research. For the first time, this review summarises the reverse TCA cycle and alternative oxidase pathway, which are unique metabolic bypasses in invertebrates that have emerged as suitable targets for the formulation of low-toxicity molluscicides. Additionally, it highlights the importance of other metabolic pathways, including lactate, alanine, glycogenolysis, and pentose phosphate pathways, in snail energy supply, antioxidant stress responses, and drug evasion mechanisms. By analysing the alterations in key metabolic enzymes and their products in stressed snails, this review deepens our understanding of glucose metabolic alterations in snails and provides valuable insights for identifying new pharmacological targets.

Silver nanoparticles induce liver inflammation through ferroptosis in zebrafish

As the most widely employed artificial nanomaterials, silver nanoparticles (AgNPs) have been implicated in oxidative stress-induced liver injury. Despite these observations, the precise mechanisms underpinning AgNPs-induced hepatotoxicity have yet to be fully elucidated. This study embarked on an intersectional analysis of the GEO dataset (GSE139560), which encompassed murine liver tissues subjected to AgNPs, alongside datasets related to ferroptosis. Through this approach, three pivotal ferroptosis-associated genes (Arrdc3, Txnip, and Egfr) were identified. Further integration with disease model analysis from GSE111407 and GSE183158 unveiled a significant association between AgNPs exposure and alterations in glucose metabolism and insulin signaling pathways, intricately linked with the identified key ferroptosis genes. This correlation fostered the hypothesis that ferroptosis significantly contributed to the hepatotoxicity triggered by AgNPs. Subsequent Gene Set Enrichment Analysis (GSEA) pointed to the activation of ferroptosis-associated pathways, specifically MAPK and PPAR, under AgNPs exposure. Examination of the miRNA-mRNA interaction network revealed co-regulated upstream miRNAs targeting these pivotal genes, establishing a nexus to ferroptosis and heightened liver susceptibility. Experimental validation employing an adult zebrafish model exposed to AgNPs from 90 to 120 dpf demonstrated elevated levels of Fe2+ and MDA in the zebrafish livers, along with conspicuous mitochondrial morphological alterations, thereby reinforcing the notion that AgNPs precipitate liver dysfunction predominantly through the induction of ferroptosis. These insights collectively underscore the role of ferroptosis in mediating the adverse effects of AgNPs on liver glucose metabolism and insulin sensitivity, culminating in liver dysfunction. Overall, these results enhance the understanding of nanomaterial-induced hepatotoxicity and inform strategies to mitigate such health risks.

Alanine aminotransferase predicts incident steatotic liver disease of metabolic etiology: Long life to the old biomarker!

Alanine aminotransferase (ALT) serum levels increase because of hepatocellular damage. Metabolic dysfunction-associated fatty liver disease (MAFLD), which identifies steatotic liver disease (SLD) associated with ≥ 2 metabolic abnormalities, has prominent sexual differences. The Metabolic Syndrome defines a cluster comprising abdominal obesity, altered glucose metabolism, dyslipidemia, and hypertension. Male sex, body mass index, glucose, lipids, ferritin, hypertension, and age independently predict ALT levels among blood donors. Over the last few decades, the reference range of ALT levels has been animatedly debated owing to attempts to update sex-specific reference ranges. With this backset, Chen et al have recently published a study which has two main findings. First, > 80% of individuals with MAFLD had normal ALT levels. Second, there was a linear increasing trend in the association between cumulative excess high-normal ALT levels and the rate of incident MAFLD. This study has biologically credible findings. However, it inaccurately considered sex differences in the MAFLD arena. Therefore, future studies on SLD owing to metabolic dysfunction should adopt locally determined and prospectively validated reference ranges of ALT and carefully consider sex differences in liver enzymes and MAFLD pathobiology.

Short-Term Postnatal Overfeeding Induces Long-Lasting Cardiometabolic Syndrome in Mature and Old Mice Associated with Increased Sensitivity to Myocardial Infarction.

Perinatal nutritional disturbances may "program" an increased cardio-metabolic risk in adulthood; however, few experimental studies have explored their effects on mature and/or old animal. This study aims to investigate the influence of postnatal overfeeding (PNOF) on cardiac function, sensitivity to ischemia-reperfusion (I-R) injury in vivo, glucose metabolism, and metabolic profile of pericardial adipose tissue (PAT) in young (4 months), adult (6 months), old (12 months), and very old (18 months) male mice. Two days after birth, PNOF is induced by adjusting the litter size of C57BL/6 male mice to three pups/mother, while the normally fed (NF) control group is normalized to nine pups/mother. After weaning, all mice have free access to standard diet. Glucose/insulin tests and in vivo myocardial I-R injury are conducted on mice aged from 2 to 12 months, while echocardiography is performed at all ages up to 18 months. PNOF mice exhibit an early and persistent 10-20% increase in body weight and a 10% decrease in left ventricular ejection fraction throughout their lifespan. In PNOF mice aged 4, 6, and 12 months, glucose intolerance and insulin resistance are observed, as well as a 27-34% increase in infarct size. This is accompanied by a higher PAT mass with increased inflammatory status. Short-term PNOF results in nutritional programming, inducing long-lasting alterations in glucose metabolism and cardiac vulnerability in male mice, lasting up to 12 months.

PI3K/AKT signaling alters glucose metabolism in uterine microenvironment of women with idiopathic recurrent spontaneous miscarriage

BackgroundThis study aims to identify metabolomic signatures in uterine fluid of women with idiopathic recurrent spontaneous miscarriage (IRSM) during window of implantation (WOI). Also, glucose transporters GLUT3 and GLUT4 and proteins of PI3K-Akt signaling pathway in endometrial tissue are assessed. MethodsPaired uterine fluid and endometrial biopsies were collected during WOI from women with IRSM (n = 24) and healthy women with azoospermic male partners as controls (n = 15). NMR metabolomics was used to identify the dysregulated metabolites in uterine fluid of IRSM women. Additionally, proteins and glucose transporters were investigated in the endometrial tissue using immunohistochemistry (IHC) and western blotting. ResultsUterine fluid metabolomics indicated eleven metabolites to be significantly downregulated in IRSM. While expression levels of PI3K (p85), PI3K (p110), p-Akt (Thr308), p-Akt (Ser473), GLUT3 and GLUT4 were significantly downregulated in endometrial tissue of these women, p-IKK α/β (Ser176/180) and p-NFkBp65 (Ser536) were significantly increased. ConclusionOur findings suggest that dysregulation of PI3K/Akt pathway in the uterine microenvironment could be a likely cause of endometrial dysfunction, thereby affecting implantation. Further studies on the downstream effects of the Akt signaling pathway in-vitro for improved understanding of the Akt-mediated cellular responses in IRSM is, therefore, warranted.

IMG-31. DEUTERIUM METABOLIC IMAGING OF RESPONSE TO PRECISION THERAPY IN BRAF-V600E MUTANT GLIOMAS

Abstract BACKGROUND Oncogenic BRAF-V600E mutations are frequently observed in low- and high-grade gliomas in children. BRAF transduces signals from receptor tyrosine kinases to downstream effectors such as MEK1/2 and ERK, which regulate metabolism and proliferation. The combination of the BRAF-V600E inhibitor dabrafenib and the MEK1/2 inhibitor trametinib (Dab/Tra) improves patient survival. However, there is considerable variation in response durability, underscoring the need for early biomarkers of treatment response. Magnetic resonance imaging (MRI), which is the gold standard for patient management, does not reliably assess response to therapy. Since the BRAF/MEK pathway regulates metabolism, the goal of this study was to determine whether Dab/Tra induces alterations in glucose metabolism that can be leveraged for non-invasive imaging of response to therapy. METHODS We performed gene expression profiling, in vivo metabolomics, stable isotope tracing, and deuterium metabolic imaging in patient-derived and syngeneic BRAF-V600E mutant models (AM38, 2341). RESULTS Our studies indicate that Dab/Tra downregulates glucose metabolism to lactate in AM38 and 2341 cells. In vivo infusion with [U-13C]-glucose in mice bearing intracranial AM38 tumors confirmed that Dab/Tra downregulates 13C-lactate production in the tumor. Mechanistically, Dab/Tra destabilizes hypoxia inducible factor-1a and downregulates glycolytic genes, including SLC2A1, HK2, PFKFB3, and LDHA. Importantly, deuterium metabolic imaging using [6,6’-2H]-glucose, which is a clinical stage method of imaging glycolysis, shows a reduction in lactate production within 48h of treatment with Dab/Tra in AM38 tumor-bearing mice. CONCLUSIONS Our studies mechanistically link BRAF/MEK inhibition with reduced glycolysis and identify [6,6’-2H]-glucose as a novel, non-invasive agent for imaging early response to therapy. Since [6,6’-2H]-glucose is a safe, orally administered agent, our studies can be rapidly translated to the clinic, where they will provide physicians with a much-needed tool to determine whether patients are responding to therapy at an early timepoint that predicts extended survival.

Dapagliflozin attenuates fat accumulation and insulin resistance in obese mice with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS), a common endocrine disorder affecting premenopausal women, is associated with various metabolic consequences such as insulin resistance, hyperlipidemia, obesity, and type 2 diabetes mellitus (T2DM). Insulin sensitizers, such as metformin and pioglitazone, though effective, often leads to significant gastrointestinal adverse effects or weight gain, limiting its suitability for women with PCOS. There is an urgent need for safe, effective and affordable agents. Dapagliflozin, a sodium-glucose co-transporter 2 (SGLT2) inhibitor, enhances glucose elimination through urine, thereby reducing body weight and improving glucose and lipid metabolism. Nevertheless, it is not currently recommended as a therapeutic option for PCOS in clinical guidelines. In this study, we systematically examined the impact of dapagliflozin on an obese PCOS mouse model, focusing on alterations in glucose metabolism, adipose tissue morphology, and plasma lipid profile. Obese PCOS was induced in mice by continuous dihydrotestosterone (DHEA) injections over 21 days and high-fat diet (HFD) feeding. PCOS mice were then orally gavaged with dapagliflozin (1 mg/kg), metformin (50 mg/kg), or vehicle daily for 8 weeks, respectively. Our results demonstrated that dapagliflozin significantly prevented body weight gain and reduced fat mass in obese PCOS mice. Meanwhile, dapagliflozin treatment improved glucose tolerance and increased insulin sensitivity compared to the control PCOS mice. Furthermore, dapagliflozin significantly improved adipocyte accumulation and morphology in white adipose tissue, resulting in a normalized plasma lipid profile in PCOS mice. In conclusion, our results suggest that dapagliflozin is an effective agent in managing glucose and lipid metabolism disorders in obese PCOS mice.

Advances in Foxp3+ regulatory T cells (Foxp3+ Treg) and key factors in digestive malignancies.

Foxp3+ regulatory T cells (Foxp3+ Treg) play a role in regulating various types of tumors, but uncertainty still exists regarding the exact mechanism underlying Foxp3+ Treg activation in gastrointestinal malignancies. As of now, research has shown that Foxp3+ Treg expression, altered glucose metabolism, or a hypoxic tumor microenvironment all affect Foxp3+ Treg function in the bodies of tumor patients. Furthermore, it has been demonstrated that post-translational modifications are essential for mature Foxp3 to function properly. Additionally, a considerable number of non-coding RNAs (ncRNAs) have been implicated in the activation of the Foxp3 signaling pathway. These mechanisms regulating Foxp3 may one day serve as potential therapeutic targets for gastrointestinal malignancies. This review primarily focuses on the properties and capabilities of Foxp3 and Foxp3+Treg. It emphasizes the advancement of research on the regulatory mechanisms of Foxp3 in different malignant tumors of the digestive system, providing new insights for the exploration of anticancer treatments.

Hyperglycemia and cognitive impairments anticipate the onset of an overt type 2 diabetes-like phenotype in TALLYHO/JngJ mice

Type 2 Diabetes mellitus (T2DM) is a metabolic disorder characterized by chronic hyperglycemia, resulting from deficits in insulin secretion, insulin action, or both. Whilst the role of insulin in the peripheral nervous system has been ascertained in countless studies, its role in the central nervous system (CNS) is emerging only recently. Brain insulin has been lately associated with brain disorders like Alzheimer’s disease, obsessive compulsive disorder, and attention deficit hyperactivity disorder. Thus, understanding the role of insulin as a common risk factor for mental and somatic comorbidities may disclose novel preventative and therapeutic approaches. We evaluated general metabolism (glucose tolerance, insulin sensitivity, energy expenditure, lipid metabolism, and polydipsia) and cognitive capabilities (attention, cognitive flexibility, and memory), in adolescent, young adult, and adult male and female TALLYHO/JngJ mice (TH, previously reported to constitute a valid experimental model of T2DM due to impaired insulin signaling). Adult TH mice have also been studied for alterations in gut microbiota diversity and composition. While TH mice exhibited profound deficits in cognitive flexibility and altered glucose metabolism, we observed that these alterations emerged either much earlier (males) or independent of (females) a comprehensive constellation of symptoms, isomorphic to an overt T2DM-like phenotype (insulin resistance, polydipsia, higher energy expenditure, and altered lipid metabolism). We also observed significant sex-dependent alterations in gut microbiota alpha diversity and taxonomy in adult TH mice. Deficits in insulin signaling may represent a common risk factor for both T2DM and CNS-related deficits, which may stem from (partly) independent mechanisms.

Beta cells deficient for Renalase counteract autoimmunity by shaping natural killer cell activity.

Type 1 diabetes (T1D) arises from autoimmune-mediated destruction of insulin-producing pancreatic beta cells. Recent advancements in the technology of generating pancreatic beta cells from human pluripotent stem cells (SC-beta cells) have facilitated the exploration of cell replacement therapies for treating T1D. However, the persistent threat of autoimmunity poses a significant challenge to the survival of transplanted SC-beta cells. Genetic engineering is a promising approach to enhance immune resistance of beta cells as we previously showed by inactivating the Renalase (Rnls) gene. Here, we demonstrate that Rnls loss of function in beta cells shapes autoimmunity by mediating a regulatory natural killer (NK) cell phenotype important for the induction of tolerogenic antigen-presenting cells. Rnls-deficient beta cells mediate cell-cell contact-independent induction of hallmark anti-inflammatory cytokine Tgfβ1 in NK cells. In addition, surface expression of regulatory NK immune checkpoints CD47 and Ceacam1 is markedly elevated on beta cells deficient for Rnls. Altered glucose metabolism in Rnls mutant beta cells is involved in the upregulation of CD47 surface expression. These findings are crucial to better understand how genetically engineered beta cells shape autoimmunity, giving valuable insights for future therapeutic advancements to treat and cure T1D.

Long-term impact of postnatal nutritional programming on cardiac sensitivity to ischemia-reperfusion injury in vivo and on glucose metabolism

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Fondation de France Introduction Nutritional environment during intra uterine and postnatal period has a major impact on health and disease in adulthood. The early programming of cardiometabolic risk through a postnatal overfeeding in rodents leads to a permanent increase in body weight, associated with alteration of left ventricular contractility, higher cardiac sensitivty to ischemic or chemo-toxic stresses and alterations of glucose métabolism in adulthood. However, these data have mainly obtained in young rodents and less is known for older animals. Purpose Our aim was to evaluate the impact of postnatal overfeeding (PNOF) on cardiac function, on cardiac sensitivity to ischemia-reperfusion (I-R) injury in vivo, on glucose metabolism and on metabolic profile of pericardial adipose tissue (PAT) in young (4 months), adult (6 months) and old (12 months) male mice. Methods PNOF was induced by the reduction of litter size of C57/BL6 mice immediately after birth: normally-fed group (NF) was composed of 9 male pups/mother and overfed group (PNOF) of 3 pups/mother. Echocardiography and blood sugar tests (glucose tolerance and insulin resistance) were performed at all ages. An in vivo ischemia-reperfusion injury was induced by the ligation of the left anterior descending coronary artery for 45 minutes followed by 24 h of reperfusion. PAT was harvested and weighted, in order to investigate by rt-qPCR its inflammatory status. All experiments were performed in 4-, 6- and 12-months aged mice. Results PNOF induced an early and permanent increase in body weight in PNOF group, independently of mice’s age (+23% at 24 days of life, +14% at 4 months, +23% at 6 and 12 months, compared to NF group). Echocardiographic measurements showed an alteration of left ventricular ejection fraction in mice aged from 4 months up to 12 months (-11 % on average, compared to NF groups). PNOF mice presented glucose intolerance and insulin resistance from 4 to 12 months of age. Moreover, PNOF mice had a higher PAT mass indexed to body weight with increased inflammatory status and decreased activin A mRNA expression at 6 and 12 months. Finally, PNOF induced a significant increase of infarct size at 4 months (+37%, p<0.01, n=8), 6 months (+32%, p<0.05, n=9) and 12 months (+38%, p<0,05, n=9) after cardiac surgery. Conclusion Nutritional programming through short-term PNOF induced an early and permanent overweight, an increase in pericardial fat mass with a greater inflammatory status, associated with alterations of glucose metabolism, alteration of systolic function and a higher sensitivity to ischemia reperfusion injury induced in vivo. The cellular mechanisms of these pathological modifications induced by PNOF need further exploration but could involve alterations in cardiomyocyte pathways and/or modification of global inflammatory status. Therefore, the PNOF mice model corresponds to a relevant experimental model of programmed metabolic syndrome as we known in humans.

RNA-sequencing revisited data shed new light on wooden breast myopathy

Wooden Breast (WB) abnormality represents one of the major challenges that the poultry industry has faced in the last 10 years. Despite the enormous progress in understanding the mechanisms underlying WB, the precise initial causes remain to be clarified. In this scenario, the present research is intended to characterize the gene expression profiles of broiler Pectoralis major muscles affected by WB, comparing them to the unaffected counterpart, to provide new insights into the biological mechanisms underlying this defect and potentially identifying novel genes likely involved in its occurrence. To this purpose, data obtained in a previous study through the RNA-sequencing technology have been used to identify differentially expressed genes (DEGs) between 6 affected and 5 unaffected broilers' breast muscles, by using the newest reference genome assembly for Gallus gallus (GRCg7b). Also, to deeply investigate molecular and biological pathways involved in the WB progression, pathways analyses have been performed. The results achieved through the differential gene expression analysis mainly evidenced the downregulation of glycogen metabolic processes, gluconeogenesis, and tricarboxylic acid cycle in WB muscles, thus corroborating the evidence of a dysregulated energy metabolism characterizing breasts affected by this abnormality. Also, genes related to hypertrophic muscle growth have been identified as differentially expressed (e.g., WFIKKN1). Together with that, a downregulation of genes involved in mitochondrial biogenesis and functionality has been detected. Among them, PPARGC1A and PPARGC1B chicken genes are particularly noteworthy. These genes not only have essential roles in regulating mitochondrial biogenesis but also play pivotal roles in maintaining glucose and energy homeostasis. In view of that, their downregulation in WB-affected muscle may be considered as potentially related to both the mitochondrial dysfunction and altered glucose metabolism in WB muscles, and their key involvement in the molecular alterations characterizing this muscular abnormality might be hypothesized.

Preventive and Therapeutic Efficacy of Roselle Beverage Residue in Late-Stage Type 2 Diabetic Rats

The residue from roselle beverage production is rich in polyphenols and dietary fiber. We investigated its potential as a preventive and therapeutic agent for type 2 diabetes mellitus (T2DM). Male Wistar rats were fed a high-fat high-fructose diet (HFFD) for 17 weeks, reaching insulin resistance by week 9, and induced to T2DM with streptozotocin (STZ) at week 13. Roselle beverage residue (RBR) was administered ad libitum mixed at 6% with the HFFD. Rats received HFFD+RBR as a preventive strategy starting at week 1 (healthy) and week 9 (insulin resistant), whereas the treatment strategy in T2DM rats started at week 14 alone or in combination with metformin (200 mg/kg/day), with a control metformin-treated group. All RBR-supplemented groups showed reduced serum glucose levels (1.4-fold to 1.8-fold) compared with the HFFD+STZ control group. Preventive RBR administration enhanced pancreatic function, leading to improved insulin sensitivity (6.5-fold to 7.9-fold). Gene expression analysis identified slight alterations in hepatic and skeletal muscle glucose metabolism. Additionally, RBR supplementation demonstrated a preventive role in mitigating hyperuricemia (2.1-fold to 2.2-fold), with no effect on glomerular hyperfiltration. While the exact mechanisms underlying RBR effects remain to be fully elucidated, our findings highlight its promising potential as a dietary supplement for preventing and treating T2DM.

#1207 Post transplant diabetes mellitus in kidney transplanted patients: factors related and impact on long-term outcome

Abstract Background Alterations in glucose metabolism are one of the most important complications of renal transplant recipients. The aim of this study was to analyze their prevalence and determinants and assess their influence on the main long-term clinical outcomes in a cohort of kidney transplant recipients. Methods we retrospectively analyzed the data of 832 kidney transplant recipients between 2004 and 2020 in our center. Patients were studied at 1 (T1), 6 (T6), and 12 (T12) months after transplantation and followed clinically for a follow-up time of 103 ± 60 months. At T6, an oral glucose tolerance test (OGTT) was performed in 484 patients. Results The mean age of the cohort studied was 49 ± 13 years, with a mean dialysis vintage of 54 ± 52 months. Hemodialysis was the therapy before KTx in 70.6% of patients, whereas 20.9% had been treated with peritoneal dialysis. The 8.5% of patients received a pre-emptive KTx. Fifty-seven percent of the patients were male and 83.5% had a KTx from a deceased donor. Both at T1 and T12, immunosuppressive therapy was mainly composed of steroids (average cumulative dose at T12: 2914 ± 962 mg), calcineurin inhibitors and mycophenolate. In our cohort at T12, diabetic patients were 237 (28.6%), of which 51 (6.2%) were already affected by diabetes before KTx. Of note, we diagnosed diabetes by OGTT in 23 KTxps, while in 90 KTxps, OGTT showed prediabetic alterations. Patients with glucose metabolism abnormalities were significantly older, had an altered lipid profile associated with higher BMI values and a significantly higher inflammatory index. Interestingly, our data showed that graft loss was not affected by any type of alteration of glucose metabolism. On the contrary, we found that mortality was significantly higher in patients with pre-transplant diabetes and in those with alterations in glucose metabolism detected with OGTT (both including diabetes and considering only IGT and IFG). Conclusions Our data showed that age at transplantation, lipid profile, and the inflammatory state were the variables that most influenced the development of PTDM. Interestingly, mortality was significantly associated with pre-transplant diabetes and alteration in glucose metabolism. This allowed us to highlight the impact of prediabetes status and the importance of OGTT as a screening test in post-transplant and potentially pre-transplant. Future randomized controlled trials will be able to resume the topic, including the analysis of the effects of new antidiabetic drugs.

Protein carbonylation causes sarcoplasmic reticulum Ca2+ overload by increasing intracellular Na+ level in ventricular myocytes.

Diabetes is commonly associated with an elevated level of reactive carbonyl species due to alteration of glucose and fatty acid metabolism. These metabolic changes cause an abnormality in cardiac Ca2+ regulation that can lead to cardiomyopathies. In this study, we explored how the reactive α-dicarbonyl methylglyoxal (MGO) affects Ca2+ regulation in mouse ventricular myocytes. Analysis of intracellular Ca2+ dynamics revealed that MGO (200 μM) increases action potential (AP)-induced Ca2+ transients and sarcoplasmic reticulum (SR) Ca2+ load, with a limited effect on L-type Ca2+ channel-mediated Ca2+ transients and SERCA-mediated Ca2+ uptake. At the same time, MGO significantly slowed down cytosolic Ca2+ extrusion by Na+/Ca2+ exchanger (NCX). MGO also increased the frequency of Ca2+ waves during rest and these Ca2+ release events were abolished by an external solution with zero [Na+] and [Ca2+]. Adrenergic receptor activation with isoproterenol (10nM) increased Ca2+ transients and SR Ca2+ load, but it also triggered spontaneous Ca2+ waves in 27% of studied cells. Pretreatment of myocytes with MGO increased the fraction of cells with Ca2+ waves during adrenergic receptor stimulation by 163%. Measurements of intracellular [Na+] revealed that MGO increases cytosolic [Na+] by 57% from the maximal effect produced by the Na+-K+ ATPase inhibitor ouabain (20 μM). This increase in cytosolic [Na+] was a result of activation of a tetrodotoxin-sensitive Na+ influx, but not an inhibition of Na+-K+ ATPase. An increase in cytosolic [Na+] after treating cells with ouabain produced similar effects on Ca2+ regulation as MGO. These results suggest that protein carbonylation can affect cardiac Ca2+ regulation by increasing cytosolic [Na+] via a tetrodotoxin-sensitive pathway. This, in turn, reduces Ca2+ extrusion by NCX, causing SR Ca2+ overload and spontaneous Ca2+ waves.

Regulation of macrophage polarization and glucose metabolism by the ERK/MAPK-HK1 signaling pathway in paraquat-induced acute lung injury

Acute lung injury is the leading cause of paraquat (PQ) poisoning-related mortality. The mechanism by which macrophages are involved in PQ-induced acute lung injury remains unclear. In recent years, the role of metabolic reprogramming in macrophage functional transformation has received significant attention. The current study aimed to identify the role of altered macrophage glucose metabolism and molecular mechanisms in PQ poisoning-induced acute lung injury. We established a model of acute lung injury in PQ-intoxicated mice via the intraperitoneal injection of PQ. PQ exposure induces macrophage M1 polarization and promotes the release of inflammatory factors, which causes the development of acute lung injury in mice. In vitro analysis revealed that PQ altered glucose metabolism, which could be reversed by siRNA transfection to silence the expression of HK1, a key enzyme in glucose metabolism. RNA sequencing revealed that the ERK/MAPK pathway was the crucial molecular mechanism of PQ pathogenesis. Further, U0126, an ERK inhibitor, could inhibit PQ-induced HK1 activation and macrophage M1 polarization. These findings provide novel insights into the previously unrecognized mechanism of ERK/MAPK-HK1 activation in PQ poisoning.

A novel compounded cyproheptadine hydrochloride oral solution: Accelerated stability study and effects on glucose and lipid metabolism in Wistar rats

The present study developed a compounded oral solution (COS) containing an active component cyproheptadine hydrochloride (CY) in association with pharmaceutical adjuvants. The main objective is to demonstrate the stability of this solution and the in vivo effects on serum and liver parameters of glucose and lipid metabolism. After 180 days of analysis the COS showed physicochemical stability (pH and specific gravity) when submitted to different temperatures (24 °C and 40 °C), but the chemical stability, presented by the content of CY (%) in the formulation, showed that the degradation rate of CY increased 20x when submitted to a stress condition (40 °C). Male Wistar rats were treated with IOS 1.5 (industrial oral solution 1.5 mg.kg-1) or saline for 21 days and IOS 5.0 or COS (5 mg.kg-1) or placebo by gavage for 23 days. Treatment with IOS 1.5 increased liver cholesterol by 30 % without changing liver and body weight in this group. In contrast, treatment with IOS and COS (5 mg.kg-1) increased final body weight by 8 % compared to placebo. Interestingly, the COS group had increased liver glycogen accompanied by reduced food intake compared to IOS. However, COS and IOS 5.0 did not induce changes in adipose tissue weight, liver weight, as well as serum glucose, triacylglycerol and cholesterol levels. This work provides us with data that prove the stability of the compound solution at room temperature, as well as inducing an increase in the final body weight of rats with no alteration in glucose and lipid metabolism.

Post-Transplant Diabetes Mellitus in Kidney-Transplanted Patients: Related Factors and Impact on Long-Term Outcome.

This study aimed to investigate the prevalence and determinants of glucose metabolism abnormalities and their impact on long-term clinical outcomes in kidney transplant recipients (KTxps). A retrospective analysis of 832 KTxps (2004-2020) was performed. Patients were assessed at 1 (T1), 6 (T6), and 12 (T12) months post-transplantation and clinically followed for an average of 103 ± 60 months. At T6, 484 patients underwent an oral glucose tolerance test for the diagnosis of alterations in glucose metabolism (AMG+) or post-transplant diabetes mellitus (PTDM+). The prevalence of pre-transplant diabetes was 6.2%, with 22.4% of PTDM+ within the 1st year. Patients with AMG were older and exhibited altered lipid profiles, higher body mass index, and increased inflammatory indices. Age at transplantation, lipid profile, and inflammatory status were significant determinants of PTDM. Graft loss was unaffected by glucose metabolism alterations. Survival analysis demonstrated significantly worse long-term survival for KTxps with diabetes (pre- and PTDM+, p = 0.04). In a comparison of the ND and PTDM+ groups, no significant differences in death with a functioning graft were found. The AMG+ group exhibited worse survival (p < 0.001) than AMG-, even after excluding patients with diabetes mellitus. Future randomized controlled trials are necessary to delve deeper into this subject, specifically examining the effects of new antidiabetic treatments.

Metabolic Reprogramming: A Byproduct or a Driver of Cardiomyocyte Proliferation?

Defining mechanisms of cardiomyocyte proliferation should guide the understanding of endogenous cardiac regeneration and could lead to novel treatments for diseases such as myocardial infarction. In the neonatal heart, energy metabolic reprogramming (phenotypic alteration of glucose, fatty acid, and amino acid metabolism) parallels cell cycle arrest of cardiomyocytes. The metabolic reprogramming occurring shortly after birth is associated with alterations in blood oxygen levels, metabolic substrate availability, hemodynamic stress, and hormone release. In the adult heart, myocardial infarction causes metabolic reprogramming but these changes cannot stimulate sufficient cardiomyocyte proliferation to replace those lost by the ischemic injury. Some putative pro-proliferative interventions can induce the metabolic reprogramming. Recent data show that altering the metabolic enzymes PKM2 [pyruvate kinase 2], LDHA [lactate dehydrogenase A], PDK4 [pyruvate dehydrogenase kinase 4], SDH [succinate dehydrogenase], CPT1b [carnitine palmitoyl transferase 1b], or HMGCS2 [3-hydroxy-3-methylglutaryl-CoA synthase 2] is sufficient to partially reverse metabolic reprogramming and promotes adult cardiomyocyte proliferation. How metabolic reprogramming regulates cardiomyocyte proliferation is not clearly defined. The possible mechanisms involve biosynthetic pathways from the glycolysis shunts and the epigenetic regulation induced by metabolic intermediates. Metabolic manipulation could represent a new approach to stimulate cardiac regeneration; however, the efficacy of these manipulations requires optimization, and novel molecular targets need to be defined. In this review, we summarize the features, triggers, and molecular regulatory networks responsible for metabolic reprogramming and discuss the current understanding of metabolic reprogramming as a critical determinant of cardiomyocyte proliferation.

The interplay between excess weight and hyper-glycemia on NCDs in Italy: results from a cross-sectional study

PurposeTo evaluate the prevalence of chronic comorbidities according to BMI classes and assess the interplay between excess body weight and blood glucose abnormalities in increasing the risk of major chronic diseases.MethodsThe study is based on data from the Health Search/IQVIA Health LPD Longitudinal Patient Database, an Italian general practice registry, with data obtained from electronic clinical records of 800 general practitioners throughout Italy. Data relative to the year 2018 were analyzed. The study population was classified according to BMI (normal weight, overweight, and obesity classes 1, 2 and 3) and glucose metabolism status (normoglycemia—NGT; impaired fasting glucose—IFG; diabetes mellitus—DM). Comorbidities were identified through ICD-9 CM codes.ResultsData relative to 991,917 adults were analyzed. The prevalence of overweight was 39.4%, while the prevalence of obesity was 11.1% (class 1: 7.9%, class 2: 2.3%, class 3: 0.9%). In the whole population, the prevalence of DM and IFG was 8.9% and 4.2%, respectively. Both overweight and obesity were associated with an increasing prevalence of glucose metabolism alterations and a large array of different chronic conditions, including cardio-cerebrovascular diseases, heart failure, chronic kidney disease, osteoarticular diseases, depression, sleep apnea, and neoplasms of the gastrointestinal tract. Within each BMI class, the presence of IFG, and to a greater extent DM, identified subgroups of individuals with a marked increase in the risk of concomitant chronic conditions.ConclusionAddressing the double burden of excess weight and hyperglycemia represents an important challenge and a healthcare priority.