Molecular pathways associated with oxidative stress in diabetes mellitus

Advances in Traditional Chinese Medicine research in diabetic kidney disease treatment

CONTEXT

Diabetic kidney disease (DKD) is a prominent complication arising from diabetic microangiopathy, and its prevalence and renal impact have placed it as the primary cause of end-stage renal disease. Traditional Chinese Medicine (TCM) has the distinct advantage of multifaceted and multilevel therapeutic attributes that show efficacy in improving clinical symptoms, reducing proteinuria, protecting renal function, and slowing DKD progression. Over recent decades, extensive research has explored the mechanisms of TCM for preventing and managing DKD, with substantial studies that endorse the therapeutic benefits of TCM compounds and single agents in the medical intervention of DKD.

OBJECTIVE

This review lays the foundation for future evidence-based research efforts and provide a reference point for DKD investigation.

METHODS

The relevant literature published in Chinese and English up to 30 June 2023, was sourced from PubMed, Cochrane Library, VIP Database for Chinese Technical Periodicals (VIP), Wanfang Data, CNKI, and China Biology Medicine disc (CBM). The process involved examining and summarizing research on TCM laboratory tests and clinical randomized controlled trials for DKD treatment.

RESULTS AND CONCLUSIONS

The TCM intervention has shown the potential to inhibit the expression of inflammatory cytokines and various growth factors, lower blood glucose levels, and significantly affect insulin resistance, lipid metabolism, and improved renal function. Furthermore, the efficacy of TCM can be optimized by tailoring personalized treatment regimens based on the unique profiles of individual patients. We anticipate further rigorous and comprehensive clinical and foundational investigations into the mechanisms underlying the role of TCM in treating DKD.

Phenolic content of Thai Bao mango peel and its in-vitro antioxidant, anti-cholinesterase, and antidiabetic activities

Plant phenolics have been known for various biological activities. This study aims to extract and examine the presence of phenolics in Bao mango (Mangifera indica L. var.) peel ethanolic extract (MPE). Further, antioxidant, anti-diabetic (α-amylase, and α-glucosidase inhibitory activity), and anti- Alzheimer's disease (AD) (acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and β-secretase (BACE-1) inhibitory activity) efficacy of MPE were determined. The results indicated that mangiferin (8755.89 mg/ 100 g extract) was the major phenolic compound in MPE. An antioxidant mechanism revealed that MPE had a higher radical scavenging ability (4266.70 µmol TE/g extract) compared to reducing power (FRAP) or oxygen radical absorption capacity (ORAC). Further in-vitro enzyme inhibitory assay against diabetic and AD involved enzymes showed that MPE had stronger inhibitory action against an enzyme involved in diabetes compared to their standard drug (Acarbose) (P < 0.05). While a lower IC50 value was observed against AD-involved enzymes compared to their standard drug (donepezil) (P < 0.05). The results show that Thai Bao mango peel byproduct can be a potential source of nutraceuticals to lower diabetes and improve cognitive health.

The antioxidant, antidiabetic, and antihyperlipidemic effects of the polyphenolic extract from Salvia blancoana subsp. mesatlantica on induced diabetes in rats

Currently, several studies have demonstrated the benefits of medicinal plants in managing type 2 diabetes. In this work, we evaluated the beneficial effects of the polyphenolic extract (PESB) from Salvia blancoana subsp. mesatlantica in the management of hypercaloric-feeding and small-dose alloxan-brought type 2 diabetes in rats. We analyzed the chemical constituents of the extract, including flavones and flavonols content, to understand its biological action. The antioxidant activities were evaluated by total antioxidant action, scavenging effect of the free radical DPPH, and reducing power. The obtained results showed that the value of TFC was estimated at 31.90 ± 0.34 mgEQ/g in the PESB extract. The total antioxidant capacity was estimated at 593.51 ± 4.09 mg (EAA)/g, the value of DPPH IC50 was 7.3 ± 0.00 μg/mL, and the value of EC50 of reducing power was estimated at 6.43 ± 0.01 μg/mL. In total, 14 phenolic compounds were identified and the naringin was the most dominant (63.19%) while the vanillin was the less recorded (0.10%). Serum glucose decreased significantly (p < 0.05) in rats given PESB (100 mg/kg) after four weeks. Glibenclamide (GLB) and PESB reduced HbA1c and increased plasma insulin in diabetic rats, restoring HOMA-β and HOMA-IR levels to near-normal. Additionally, diabetic rats treated with GLB or PESB showed statistically equivalent results to those of non-diabetic rats regarding hepatic enzymes, renal and lipid markers, as well as cardiovascular indices. The weight loss was significantly lower in diabetic rats receiving a dose of PESB (100 mg/kg), and GLB compared to corresponding untreated diabetic rats (p < 0.01). PESB and GLB showed a prominent protective function in the pancreas, liver, and kidney tissues. This investigation demonstrates the capacity of extracts from leaves of S. blancoana subsp. mesatlantica to manage diabetes mellitus due to their richness in a wide range of bioactive compounds. Therefore, more investigations are required to estimate the safety of the plant use.

Relationship of urinary glyphosate concentrations with glycosylated hemoglobin and diabetes in US adults: a cross-sectional study

BACKGROUND

Glyphosate is a commonly used herbicide worldwide and is purportedly associated with multiple health effects. Research assessing the association of glyphosate concentrations with glycosylated hemoglobin (HbA1c) levels and the prevalence of diabetes is scarce. We sought to evaluate the association between urinary glyphosate levels and HbA1c levels and the prevalence of diabetes.

METHODS

A total of 2,745 adults in the National Health and Nutrition Examination Survey from 2013 to 2016 were included in this study. Generalized linear models (GLM) were applied to evaluate the associations of glyphosate concentrations with HbA1c levels and the prevalence of diabetes. The dose-response relationship was examined using restricted cubic splines (RCS).

RESULTS

Significantly positive correlations of urinary glyphosate concentrations with HbA1c levels (percentage change: 1.45; 95% CI: 0.95, 1.96; P < 0.001) and the prevalence of diabetes (OR: 1.45; 95% CI: 1.24, 1.68; P < 0.001) were found after adjustment. Compared with the lowest quartile of glyphosate levels, the highest quartile was positively associated with HbA1c levels (percentage change: 4.19; 95% CI: 2.54, 5.85; P < 0.001) and the prevalence of diabetes (OR: 1.89; 95% CI: 1.37, 2.63; P < 0.001). The RCS curves demonstrated a monotonically increasing dose-response relationship between urinary glyphosate levels and the prevalence of diabetes and HbA1c levels.

CONCLUSIONS

Urinary glyphosate concentrations are positively associated with HBA1c levels and the prevalence of diabetes. To verify our findings, additional large-scale prospective investigations are required.

Overexpression of MD1 ameliorates pathological myocardial remodeling in diabetic cardiomyopathy by TLR4/STAT3 signaling pathway

Diabetic cardiomyopathy (DCM) is characterized by oxidative damage and inflammatory responses. Myeloid differentiation protein 1 (MD1) exhibits antioxidant and anti-inflammatory properties. However, the specific role of MD1 in DCM has yet to be elucidated. This study aims to investigate the role of MD1 in DCM and to elucidate the underlying mechanisms. We utilized a gain-of-function approach to explore the involvement of MD1 in DCM. Diabetes was induced in MD1-transgenic (MD1-TG) mice and their wild-type (WT) counterparts via streptozotocin (STZ) injection. Additionally, a diabetes cell model was established using H9c2 cells exposed to high glucose levels. We conducted comprehensive evaluations, including pathological analyses, echocardiography, electrocardiography, and molecular assessments, to elucidate the underlying mechanisms of MD1 in DCM. Notably, MD1 expression was reduced in the hearts of STZ-induced diabetic mice. Overexpression of MD1 significantly improved cardiac function and markedly inhibited ventricular pathological hypertrophy and fibrosis in these mice. Furthermore, MD1 overexpression resulted in a substantial decrease in myocardial reactive oxygen species (ROS) accumulation, mitigating myocardial oxidative stress and reducing the levels of inflammation-related markers such as IL-1β, IL-6, and TNF-α. Mechanistically, MD1 overexpression inhibited the activation of the TLR4/STAT3 signaling pathway, as demonstrated in both in vivo and in vitro experiments. The overexpression of MD1 significantly impeded pathological cardiac remodeling and improved cardiac function in STZ-induced diabetic mice. This effect was primarily attributed to a reduction in ROS accumulation and mitigation of myocardial oxidative stress and inflammation, facilitated by the inhibition of the TLR4/STAT3 signaling pathway.

Insights into the Role of Glutathione Peroxidase 3 in Non-Neoplastic Diseases

Reactive oxygen species (ROSs) are byproducts of normal cellular metabolism and play pivotal roles in various physiological processes. Disruptions in the balance between ROS levels and the body's antioxidant defenses can lead to the development of numerous diseases. Glutathione peroxidase 3 (GPX3), a key component of the body's antioxidant system, is an oxidoreductase enzyme. GPX3 mitigates oxidative damage by catalyzing the conversion of hydrogen peroxide into water. Beyond its antioxidant function, GPX3 is vital in regulating metabolism, modulating cell growth, inducing apoptosis and facilitating signal transduction. It also serves as a significant tumor suppressor in various cancers. Recent studies have revealed aberrant expression of GPX3 in several non-neoplastic diseases, associating it with multiple pathological processes. This review synthesizes the current understanding of GPX3 expression and regulation, highlighting its extensive roles in noncancerous diseases. Additionally, this paper evaluates the potential of GPX3 as a diagnostic biomarker and explores emerging therapeutic strategies targeting this enzyme, offering potential avenues for future clinical treatment of non-neoplastic conditions.

Improvement of Theaflavins on Glucose and Lipid Metabolism in Diabetes Mellitus

In diabetes mellitus, disordered glucose and lipid metabolisms precipitate diverse complications, including nonalcoholic fatty liver disease, contributing to a rising global mortality rate. Theaflavins (TFs) can improve disorders of glycolipid metabolism in diabetic patients and reduce various types of damage, including glucotoxicity, lipotoxicity, and other associated secondary adverse effects. TFs exert effects to lower blood glucose and lipids levels, partly by regulating digestive enzyme activities, activation of OATP-MCT pathway and increasing secretion of incretins such as GIP. By the Ca2+-CaMKK ꞵ-AMPK and PI3K-AKT pathway, TFs promote glucose utilization and inhibit endogenous glucose production. Along with the regulation of energy metabolism by AMPK-SIRT1 pathway, TFs enhance fatty acids oxidation and reduce de novo lipogenesis. As such, the administration of TFs holds significant promise for both the prevention and amelioration of diabetes mellitus.

Acylated anthocyanins from Dendrobium officinale Kimura & Migo: Structural characteristics, antioxidant and hypoglycemic activities

Dendrobium officinale Kimura & Migo (D. officinale) has been widely used as Chinese medicine and functional food. In present study, the structural characteristics of anthocyanins in D. officinale were investigated by ultra-performance liquid chromatography with diode array detector (UPLC-DAD) and ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry (UPLC-Q-TOF-MS/MS). Totally, 14 anthocyanins were detected and identified, and 13 of them were first reported in D. officinale. Results showed that the vast majority of anthocyanins had multi-glycosylated cyanidin core, with variable acylation pattern mainly comprising phenolic acids. The composition and content of anthocyanins in D. officinale stems with different cultivation modes and years have been compared. The anthocyanins showed potent antioxidant activity in terms of radicals scavenging capacity and reducing power, as well as superior α-amylase and α-glucosidase inhibitory activity. The results provided a complete profile of anthocyanins in D. officinale and laid a foundation for further utilizing them as functional foods.

The complex landscape of intracellular signalling in protein modification under hyperglycaemic stress leading to metabolic disorders

Hyperglycaemia is a life-threatening risk factor that occurs in both chronic and acute phases and has been linked to causing injury to many organs. Protein modification was triggered by hyperglycaemic stress, which resulted in pathogenic alterations such as impaired cellular function and tissue damage. Dysregulation in cellular function increases the condition associated with metabolic disorders, including cardiovascular diseases, nephropathy, retinopathy, and neuropathy. Hyperglycaemic stress also increases the proliferation of cancer cells. The major areas of experimental biomedical research have focused on the underlying mechanisms involved in the cellular signalling systems involved in diabetes-associated chronic hyperglycaemia. Reactive oxygen species and oxidative stress generated by hyperglycaemia modify many intracellular signalling pathways that result in insulin resistance and β-cell function degradation. The dysregulation of post translational modification in β cells is clinically associated with the development of diabetes mellitus and its associated diseases. This review will discuss the effect of hyperglycaemic stress on protein modification and the cellular signalling involved in it. The focus will be on the significant molecular changes associated with severe metabolic disorders.

Study on the mechanisms by which pumpkin polysaccharides regulate abnormal glucose and lipid metabolism in diabetic mice under oxidative stress

Pumpkin polysaccharide (PPe-H) can perform physiological functions through its antioxidative and hypoglycemic effects; however, the mechanisms through which PPe-H regulates abnormal glucose and lipid metabolism caused by oxidative stress injury remain unclear. In the present study, streptozotocin was used to generate an acute diabetic mouse model, and the effects of PPe-H on glucose and lipid metabolism impaired by oxidative stress in diabetic mice were studied. PPe-H significantly reduced blood glucose levels and enhanced the oral glucose tolerance of diabetic mice under stress injury (p < 0.05). The analysis of liver antioxidant enzymes showed that PPe-H significantly enhanced the activities of SOD and CAT (p < 0.05), increased the GSH level, and decreased the level of MDA (p < 0.05). Transcriptomic and metabolomic analyses of the liver tissues of mice revealed characteristic differences in the genetic and metabolic levels of the samples, which showed that PPe-H treatment may play a positive role in regulating the metabolism of methionine, cysteine, glycerol phospholipid, and linoleic acid. These results indicated that PPe-H alleviated the symptoms of hyperglycemia by regulating metabolites related to oxidative stress and glycolipid metabolism in diabetic mice.

Kaempferol efficacy in metabolic diseases: Molecular mechanisms of action in diabetes mellitus, obesity, non-alcoholic fatty liver disease, steatohepatitis, and atherosclerosis

The incidence of metabolic diseases has progressively increased, which has a negative impact on human health and life safety globally. Due to the good efficacy and limited side effects, there is growing interest in developing effective drugs to treat metabolic diseases from natural compounds. Kaempferol (KMP), an important flavonoid, exists in many vegetables, fruits, and traditional medicinal plants. Recently, KMP has received widespread attention worldwide due to its good potential in the treatment of metabolic diseases. To promote the basic research and clinical application of KMP, this review provides a timely and comprehensive summary of the pharmacological advances of KMP in the treatment of four metabolic diseases and its potential molecular mechanisms of action, including diabetes mellitus, obesity, non-alcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH), and atherosclerosis. According to the research, KMP shows remarkable therapeutic effects on metabolic diseases by regulating multiple signaling transduction pathways such as NF-κB, Nrf2, AMPK, PI3K/AKT, TLR4, and ER stress. In addition, the most recent literature on KMP's natural source, pharmacokinetics studies, as well as toxicity and safety are also discussed in this review, thus providing a foundation and evidence for further studies to develop novel and effective drugs from natural compounds. Collectively, our manuscript strongly suggested that KMP could be a promising candidate for the treatment of metabolic diseases.

Photoacoustic Imaging-Guided Self-Adaptive Hyperthermia Supramolecular Cascade Nano-Reactor for Diabetic Periodontal Bone Regeneration

Commencing with the breakdown of the diabetic osteoimmune microenvironment, multiple pathogenic factors, including hyperglycemia, inflammation, hypoxia, and deleterious cytokines, are conjointly involved in the progression of diabetic periodontal bone regeneration. Based on the challenge of periodontal bone regeneration treatment and the absence of real-time feedback of blood oxygen fluctuation in diabetes mellitus, a novel self-adaptive hyperthermia supramolecular cascade nano-reactor ACFDG is constructed via one-step supramolecular self-assembly strategy to address multiple factors in diabetic periodontal bone regeneration. Hyperthermia supramolecular ACFDG possesses high photothermal conversion efficiency (32.1%), and it can effectively inhibit the vicious cycle of ROS-inflammatory cascade through catalytic cascade reactions, up-regulate the expression of heat shock proteins (HSPs) under near-infrared (NIR) irradiation, which promotes periodontal bone regeneration. Remarkably, ACFDG can provide real-time non-invasive diagnosis of blood oxygen changes during periodontal bone regeneration through photoacoustic (PA) imaging, thus can timely monitor periodontal hypoxia status. In conclusion, this multifunctional supramolecular nano-reactor combined with PA imaging for real-time efficacy monitoring provides important insights into the biological mechanisms of diabetic periodontal bone regeneration and potential clinical theranostics.

Exploring Folklore Ecuadorian Medicinal Plants and Their Bioactive Components Focusing on Antidiabetic Potential: An Overview

Diabetes mellitus (DM) is a global health concern characterized by a deficiency in insulin production. Considering the systemic toxicity and limited efficacy associated with current antidiabetic medications, there is the utmost need for natural, plant-based alternatives. Herbal medicines have experienced exponential growth in popularity globally in recent years for their natural origins and minimal side effects. Ecuador has a rich cultural history in ethnobotany that plays a crucial role in its people's lives. This study identifies 27 Ecuadorian medicinal plants that are traditionally used for diabetes treatment and are prepared through infusion, decoction, or juice, or are ingested in their raw forms. Among them, 22 plants have demonstrated hypoglycemic or anti-hyperglycemic properties that are rich with bioactive phytochemicals, which was confirmed in several in vitro and in vivo studies. However, Bryophyllum gastonis-bonnieri, Costus villosissimus, Juglans neotropica, Pithecellobium excelsum, and Myroxylon peruiferum, which were extensively used in traditional medicine preparation in Ecuador for many decades to treat diabetes, are lacking in pharmacological elucidation. The Ecuadorian medicinal plants used to treat diabetes have been found to have several bioactive compounds such as flavonoids, phenolics, fatty acids, aldehydes, and terpenoids that are mainly responsible for reducing blood sugar levels and oxidative stress, regulating intestinal function, improving insulin resistance, inhibiting α-amylase and α-glucosidase, lowering gluconeogenic enzymes, stimulating glucose uptake mechanisms, and playing an important role in glucose and lipid metabolism. However, there is a substantial lack of integrated approaches between the existing ethnomedicinal practices and pharmacological research. Therefore, this review aims to discuss and explore the traditional medicinal plants used in Ecuador for treating DM and their bioactive phytochemicals, which are mainly responsible for their antidiabetic properties. We believe that the use of Ecuadorian herbal medicine in a scientifically sound way can substantially benefit the local economy and industries seeking natural products.

Hypoglycemic Effects of Extracts Obtained from Endemic Betonica bulgarica Degen and Neič

The increasing prevalence of diabetes mellitus, together with the limited access of many patients to conventional antidiabetic drugs and the side effects resulting from their use, are the reason for the ever-increasing need for new agents. One of the most important strategies used in the therapy of this disease is to reduce the postprandial blood glucose level by inhibiting the carbohydrate-degrading enzymes α-amylase and α-glucosidase. The purpose of the present study was to provide in vitro evidence for the potential hypoglycemic effect of leaf and inflorescence aqueous extracts of Bulgarian endemic species Betonica bulgarica Degen and Neič. Total phenolic and flavonoid contents and antioxidant activities were determined by spectrophotometric methods. Qualitative and quantitative determinations of principal phenolic acids and flavonoids were performed using HPLC with a dual absorbance detector. The plant extracts were able to retard the enzymatic breakdown of starch to glucose with 50% inhibiting concentrations of 1.86 mg/mL and 1.54 mg/mL respectively for leaf and flower extract. Some of the plant constituents are proven inhibitors of α-amylase and/or α-glucosidase, but their adsorption on starch seems to be one additional mechanism for the inhibition of glucose release. Combination index analysis carried out with binary mixtures of acarbose and plant extracts showed a tendency toward synergism with an increase in concentrations and level of inhibition.

Global status and trends of metabolomics in diabetes: A literature visualization knowledge graph study

BACKGROUND

Diabetes is a metabolic disease characterized by hyperglycemia, which has increased the global medical burden and is also the main cause of death in most countries.

AIM

To understand the knowledge structure of global development status, research focus, and future trend of the relationship between diabetes and metabolomics in the past 20 years.

METHODS

The articles about the relationship between diabetes and metabolomics in the Web of Science Core Collection were retrieved from 2002 to October 23, 2023, and the relevant information was analyzed using CiteSpace6.2.2R (CiteSpace), VOSviewer6.1.18 (VOSviewer), and Bibliometrix software under R language.

RESULTS

A total of 3123 publications were included from 2002 to 2022. In the past two decades, the number of publications and citations in this field has continued to increase. The United States, China, Germany, the United Kingdom, and other relevant funds, institutions, and authors have significantly contributed to this field. Scientific Reports and PLoS One are the journals with the most publications and the most citations. Through keyword co-occurrence and cluster analysis, the closely related keywords are "insulin resistance", "risk", "obesity", "oxidative stress", "metabolomics", "metabolites" and "biomarkers". Keyword clustering included cardiovascular disease, gut microbiota, metabonomics, diabetic nephropathy, molecular docking, gestational diabetes mellitus, oxidative stress, and insulin resistance. Burst detection analysis of keyword depicted that "Gene", "microbiota", "validation", "kidney disease", "antioxidant activity", "untargeted metabolomics", "management", and "accumulation" are knowledge frontiers in recent years.

CONCLUSION

The relationship between metabolomics and diabetes is receiving extensive attention. Diabetic nephropathy, diabetic cardiovascular disease, and kidney disease are key diseases for future research in this field. Gut microbiota, molecular docking, and untargeted metabolomics are key research directions in the future. Antioxidant activity, gene, validation, mass spectrometry, management, and accumulation are at the forefront of knowledge frontiers in this field.

Combination therapy is it in the future for successfully treating peripheral diabetic neuropathy?

In 2022, the Center for Disease Control and Prevention reported that 11.3% of the United States population, 37.3 million people, had diabetes and 38% of the population had prediabetes. A large American study conducted in 2021 and supported by many other studies, concluded that about 47% of diabetes patients have peripheral neuropathy and that diabetic neuropathy was present in 7.5% of patients at the time of diabetes diagnosis. In subjects deemed to be pre-diabetes and impaired glucose tolerance there was a wide range of prevalence estimates (interquartile range (IQR): 6%-34%), but most studies (72%) reported a prevalence of peripheral neuropathy ≥10%. There is no recognized treatment for diabetic peripheral neuropathy (DPN) other than good blood glucose control. Good glycemic control slows progression of DPN in patients with type 1 diabetes but for patients with type 2 diabetes it is less effective. With obesity and type 2 diabetes at epidemic levels the need of a treatment for DPN could not be more important. In this article I will first present background information on the "primary" mechanisms shown from pre-clinical studies to contribute to DPN and then discuss mono- and combination therapies that have demonstrated efficacy in animal studies and may have success when translated to human subjects. I like to compare the challenge of finding an effective treatment for DPN to the ongoing work being done to treat hypertension. Combination therapy is the recognized approach used to normalize blood pressure often requiring two, three or more drugs in addition to lifestyle modification to achieve the desired outcome. Hypertension, like DPN, is a progressive disease caused by multiple mechanisms. Therefore, it seems likely as well as logical that combination therapy combined with lifestyle adjustments will be required to successfully treat DPN.

Cyperus peptide SFRWQ inhibits oxidation and inflammation in RAW264.7 cell model

Oxidative stress can induce many diseases. Antioxidant peptides from food sources have the advantages of good safety, high activity, and good absorbability. In this study, a pentapeptide (SFRWQ; SER-PHE-ARG-TRP-GLN) was identified in a protein hydrolysate of Cyperus (Cyperus esculentus L.). Enzyme-linked immunosorbent assay (ELISA), real-time quantitative (qPCR), immunofluorescence and other techniques were used to evaluate the anti-inflammatory and antioxidant effects of SFRWQ. SFRWQ was found to have 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging ability, help increase superoxide dismutase (SOD) and catalase (CAT) levels in RAW264.7 cells, reduce reactive oxygen species (ROS) levels, and decrease tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) gene expression and secretion. The binding score of SFRWQ to recombinant Kelch-like ECH-associated protein 1 (Keap1) was greater than that of TX6. These findings suggest that SFRWQ activates the Keap1-Nrf2 cellular antioxidant signaling pathway. According to metabolomics studies, SFRWQ increased glutathione (GSH), glutathione disulfide (GSSG), and γ-glutamylcysteine levels and decreased the levels of Prostaglandin D2 (PGD2), Prostaglandin E2 (PGE2), and Prostaglandin H2 (PGH2), which are involved in arachidonic acid metabolism, to protect cells from LPS-induced damage. By elucidating the mechanism of action of SFRWQ, we provide a reference for the development of dietary antioxidant peptides.

Increased cell-free DNA is associated with oxidative damage in patients with schizophrenia

Cell-free DNA (cfDNA) has been found to be elevated in patients with schizophrenia (SZ), potentially derived from activated apoptosis, but the underlying mechanisms remain unknown. Moreover, whether the concentrations of cfDNA are altered with disease stage has not been investigated, which limits its clinical application as an auxiliary diagnostic marker for SZ. Using an improved fluorescence correlation spectroscopy (FCS) method that does not require DNA extraction, we measured the molar concentrations of cfDNA in plasma samples of 191 patients with SZ, 78 patients with mood disorders (MD) and 65 healthy controls (HC). We also analyzed the cfDNA composition from either the nucleus or mitochondria, oxidation markers and biochemical indexes to explore the potential mechanistic associations of the increased cfDNA levels. We found that in SZ patients, the cfDNA levels were significantly increased (P = 0.003) regardless of the different disease stages or antipsychotic medication use. Furthermore, qPCR revealed that cell-free nuclear DNA (cf-nDNA) (P = 0.041) but not cell-free mitochondrial DNA (cf-mtDNA) was elevated in SZ patients. Moreover, decreased SOD activity in SZ patients (P = 0.005) was negatively correlated with cfDNA levels (P = 0.047), and fasting blood glucose was positively correlated with cfDNA levels in SZ patients (P = 0.013). Our study provides evidence to support that the elevated cfDNA may be a convenient, effective and stable trait indicator of SZ. Further analysis showed that it mainly came from nucleus, suggesting increased apoptosis, and potentially related to oxidative stress and high blood glucose levels in patients.

Circ_005077 accelerates myocardial lipotoxicity induced by high-fat diet via CyPA/p47PHOX mediated ferroptosis

The long-term high-fat diet (HFD) can cause myocardial lipotoxicity, which is characterized pathologically by myocardial hypertrophy, fibrosis, and remodeling and clinically by cardiac dysfunction and heart failure in patients with obesity and diabetes. Circular RNAs (circRNAs), a novel class of noncoding RNA characterized by a ring formation through covalent bonds, play a critical role in various cardiovascular diseases. However, few studies have been conducted to investigate the role and mechanism of circRNA in myocardial lipotoxicity. Here, we found that circ_005077, formed by exon 2-4 of Crmp1, was significantly upregulated in the myocardium of an HFD-fed rat. Furthermore, we identified circ_005077 as a novel ferroptosis-related regulator that plays a role in palmitic acid (PA) and HFD-induced myocardial lipotoxicity in vitro and in vivo. Mechanically, circ_005077 interacted with Cyclophilin A (CyPA) and inhibited its degradation via the ubiquitination proteasome system (UBS), thus promoting the interaction between CyPA and p47phox to enhance the activity of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase responsible for ROS generation, subsequently inducing ferroptosis. Therefore, our results provide new insights into the mechanisms of myocardial lipotoxicity, potentially leading to the identification of a novel therapeutic target for the treatment of myocardial lipotoxicity in the future.

Bibliometric and visual analysis on oxidative stress in gynecological and reproductive diseases: A systematic review

BACKGROUND

The imbalance between the generation and elimination of reactive oxygen species (ROS) is defined as oxidative stress (OS). Elevated levels of OS are implicated in various diseases, especially in gynecological and reproductive disorders. The abundance of recent literature makes it challenging to assimilate all available information. This bibliometric analysis seeks to depict the research landscape of OS in gynecological and reproductive diseases and to identify future hotspots and trends.

METHODS

The Web of Science Core Collection served as the source for articles related to OS in gynecological and reproductive diseases. CtieSpace and VOSviewer software were utilized to analyzed countries/regions, institutions, journals, authors, and keywords of all eligible articles.

RESULTS

A total of 1423 articles were included. There was a gradual increase in the number of publications in this field. The USA maintained the highest number of publications, with 372 articles. Cleveland Clinic was the leading institution in terms of publication volume, contributing 67 articles. In total, 6925 authors were identified. Agarwal A as the most frequently co-cited author, received 812 citations across 43 publications. The predominant clusters included "placenta," "polycystic ovary syndrome," "male infertility," and "oocyte quality." Notably, "oocyte quality'" was identified as a current key research topic.

CONCLUSION

There was an uptrend in the number of articles addressing OS in gynecological and reproductive diseases. However, international collaboration and exchange were limited. The topic of male infertility had remained a consistent area of interest, and research on oocyte quality is poised to become a potential focal point in the future.

Investigation of the Dysfunction Caused by High Glucose, Advanced Glycation End Products, and Interleukin-1 Beta and the Effects of Therapeutic Agents on the Microphysiological Artery Model

Diabetes mellitus (DM) has substantial global implications and contributes to vascular inflammation and the onset of atherosclerotic cardiovascular diseases. However, translating the findings from animal models to humans has inherent limitations, necessitating a novel platform. Therefore, herein, an arterial model is established using a microphysiological system. This model successfully replicates the stratified characteristics of human arteries by integrating collagen, endothelial cells (ECs), and vascular smooth muscle cells (VSMCs). Perfusion via a peristaltic pump shows dynamic characteristics distinct from those of static culture models. High glucose, advanced glycation end products (AGEs), and interleukin-1 beta are employed to stimulate diabetic conditions, resulting in notable cellular changes and different levels of cytokines and nitric oxide. Additionally, the interactions between the disease models and oxidized low-density lipoproteins (LDL) are examined. Finally, the potential therapeutic effects of metformin, atorvastatin, and diphenyleneiodonium are investigated. Metformin and diphenyleneiodonium mitigate high-glucose- and AGE-associated pathological changes, whereas atorvastatin affects only the morphology of ECs. Altogether, the arterial model represents a pivotal advancement, offering a robust and insightful platform for investigating cardiovascular diseases and their corresponding drug development.

Novel molecular hybrids of EGCG and quinoxaline: Potent multi-targeting antidiabetic agents that inhibit α-glucosidase, α-amylase, and oxidative stress

Diabetes mellitus is a multifactorial disease and its effective therapy often demands several drugs with different modes of action. Herein, we report a rational design and synthesis of multi-targeting novel molecular hybrids comprised of EGCG and quinoxaline derivatives that can effectively inhibit α-glucosidase, α-amylase as well as control oxidative stress by scavenging ROS. The hybrids showed superior inhibition of α-glucosidase along with similar α-amylase inhibition as compared to standard drug, acarbose. Most potent compound, 15c showed an IC50 of 0.50 μM (IC50 of acarbose 190 μM) against α-glucosidase. Kinetics studies with 15c revealed a competitive inhibition against α-glucosidase. Binding affinity of 15c (-9.5 kcal/mol) towards α-glucosidase was significantly higher than acarbose (-7.7 kcal/mol). 15c exhibited remarkably high antioxidant activity (IC50 = 18.84 μM), much better than vitamin C (IC50 = 33.04 μM). Of note, acarbose shows no antioxidant activity. Furthermore, α-amylase activity was effectively inhibited by 15c with an IC50 value of 16.35 μM. No cytotoxicity was observed for 15c (up to 40 μM) in MCF-7 cells. Taken together, we report a series of multi-targeting molecular hybrids capable of inhibiting carbohydrate hydrolysing enzymes as well as reducing oxidative stress, thus representing an advancement towards effective and novel therapeutic approaches for diabetes.

High glucose impairs human periodontal ligament cells migration through lowered microRNAs 221 and 222

OBJECTIVE

To investigate the effects of miR-221 and miR-222 and high glucose on human periodontal ligament (PL) cells morphology, cytoskeleton, adhesion, and migration.

BACKGROUND

Chronic hyperglycemia is common in uncontrolled diabetes mellitus (DM) and plays a central role in long-term DM complications, such as impaired periodontal healing. We have previously shown that high glucose increases apoptosis of human PL cells by inhibiting miR-221 and miR-222 and consequently augmenting their target caspase-3. However, other effects of miR-221/222 downregulation on PL cells are still unknown.

METHODS

Cells from young humans' premolar teeth were cultured for 7 days under 5 or 30 mM glucose. Directional and spontaneous migration on fibronectin were studied using transwell and time-lapse assays, respectively. F-actin staining was employed to study cell morphology and the actin cytoskeleton. MiR-221 and miR-222 were inhibited using antagomiRs, and their expressions were evaluated by real-time RT-PCR.

RESULTS

High glucose inhibited PL cells early adhesion, spreading, and migration on fibronectin. Cells exposed to high glucose showed reduced polarization, velocity, and directionality. They formed several simultaneous unstable and short-lived protrusions, suggesting impairment of adhesion maturation. MiR-221 and miR-222 inhibition also reduced migration, decreasing cell directionality but not significantly cell velocity. After miR-221 and miR-222 downregulation cells showed morphological resemblance with cells exposed to high glucose.

CONCLUSION

High glucose impairs human PL cells migration potentially through a mechanism involving reduction of microRNA-221 and microRNA-222 expression. These effects may contribute to the impairment of periodontal healing, especially after surgery and during guided regeneration therapies.

Overview of Ethnobotanical-Pharmacological Studies Carried Out on Medicinal Plants from the Serra da Estrela Natural Park: Focus on Their Antidiabetic Potential

The Serra da Estrela Natural Park (NPSE) in Portugal stands out as a well-preserved region abundant in medicinal plants, particularly known for their pharmaceutical applications in diabetes prevention and treatment. This comprehensive review explores these plants' botanical diversity, traditional uses, pharmacological applications, and chemical composition. The NPSE boast a rich diversity with 138 medicinal plants across 55 families identified as traditionally and pharmacologically used against diabetes globally. Notably, the Asteraceae and Lamiaceae families are prevalent in antidiabetic applications. In vitro studies have revealed their significant inhibition of carbohydrate-metabolizing enzymes, and certain plant co-products regulate genes involved in carbohydrate metabolism and insulin secretion. In vivo trials have demonstrated antidiabetic effects, including glycaemia regulation, insulin secretion, antioxidant activity, and lipid profile modulation. Medicinal plants in NPSE exhibit various activities beyond antidiabetic, such as antioxidant, anti-inflammatory, antibacterial, anti-cancer, and more. Chemical analyses have identified over fifty compounds like phenolic acids, flavonoids, terpenoids, and polysaccharides responsible for their efficacy against diabetes. These findings underscore the potential of NPSE medicinal plants as antidiabetic candidates, urging further research to develop effective plant-based antidiabetic drugs, beverages, and supplements.

Ozone exposure affects corneal epithelial fate by promoting mtDNA leakage and cGAS/STING activation

Ozone is a common air pollutant associated with various human diseases. The human ocular surface is frequently exposed to ozone in the troposphere, but the mechanisms by which ozone affects the ocular surface health remain unclear. This study aimed to establish a mouse model to investigate the effects of ozone exposure on the ocular surface and the corneal epithelium. The findings revealed that ozone exposure disrupted corneal epithelial homeostasis and differentiation, resulting in corneal squamous metaplasia. Further, ozone exposure induced oxidative damage and cytoplasmic leakage of mitochondrial DNA (mtDNA), thereby activating the cGAS/STING signaling pathway. The activation of the cGAS/STING signaling pathway triggered the activation of downstream NF-κB and TRAF6 signaling pathways, causing corneal inflammation, thereby promoting corneal inflammation and squamous metaplasia. Finally, C-176, a selective STING inhibitor, effectively prevented and treated corneal inflammation and squamous metaplasia caused by ozone exposure. This study revealed the role of mtDNA leakage-mediated cGAS/STING activation in corneal squamous epithelial metaplasia caused by ozone exposure. It also depicted the abnormal expression pattern of corneal epithelial keratin using three-dimensional images, providing new targets and strategies for preventing and treating corneal squamous metaplasia and other ocular surface diseases.

Prevalence of oral lichen planus in patients with diabetes mellitus: A cross-sectional study

OBJECTIVES

Oral lichen planus, a chronic inflammatory immune disease, occurs in the oral mucosa. We aimed to assess the prevalence and possible influencing factors of oral lichen planus in patients with diabetes mellitus.

SUBJECTS AND METHODS

This cross-sectional study involved 525 patients with diabetes mellitus and 525 controls. We collected information on blood glucose level, duration of diabetes, diabetic complications, treatment methods, other systemic diseases and medication history.

RESULTS

Oral lichen planus was significantly more prevalent in the diabetes mellitus/type 2 diabetes mellitus group than in the controls (2.3%/2.2% vs. 0.6%, p = 0.019/0.022). There was no significant association between patients with diabetes mellitus with and those without oral lichen planus in age (p = 0.195), sex (p = 0.390), blood glucose level (p = 1), duration of diabetes (p = 0.638), diabetic complications (p = 1), treatment methods (p = 0.962), other systemic diseases (p = 0.891) and medication history (p = 0.848).

CONCLUSIONS

Diabetes mellitus was associated with oral lichen planus; there was a higher prevalence of oral lichen planus in patients with diabetes mellitus/type 2 diabetes mellitus than in those without diabetes. Oral lichen planus development in patients with diabetes mellitus was not significantly associated with age, sex, blood glucose level, duration of diabetes, diabetic complications, treatment methods, other systemic diseases and medication history.

Oxidative Stress in Postbariatric Patients: A Systematic Literature Review Exploring the Long-term Effects of Bariatric Surgery

Background

The present study investigates the impact of oxidative stress after bariatric surgery in patients with obesity. This field of study has gained great interest in recent years due to the role that oxidative stress plays in metabolic diseases. Obesity, by itself, can generate an increase in reactive oxygen and nitrogen species, intensifying cellular damage and promoting the progression of adverse metabolic conditions. In this context, bariatric surgery emerges as a candidate capable of modifying oxidative stress biomarkers, facilitating the patient's metabolic recovery.

Methods

A systematic review was carried out, identifying 30 studies found in databases such as PubMed, Scopus, Web of Science, and Google Scholar. It looked at the link between oxidative stress and recovery after bariatric surgery in patients. The selection of studies was based on the measurement of oxidative stress biomarkers before and after surgical intervention.

Results

The results reveal a significant decrease in oxidative stress biomarkers after bariatric surgery. However, a notable variability in antioxidant activity is observed between different patients, as well as a significant influence of comorbidities.

Conclusions

Bariatric surgery is postulated as an effective intervention in reducing oxidative stress in patients with obesity, enhancing antioxidant activity and improving patient recovery. This finding highlights the importance of considering oxidative stress management as an integral part of postoperative care, suggesting the need to implement complementary treatment strategies to optimize health outcomes.

Identification of a novel glioblastoma multiforme molecular subtype with poor prognosis and high immune infiltration based on oxidative stress-related genes

Glioblastoma multiforme (GBM) is a highly malignant primary brain tumor with a poor prognosis. Reactive oxygen species that accumulate during tumorigenesis can cause oxidative stress (OS), which plays a crucial role in cancer cell survival. Clinical and transcriptome data of TCGA-GBM dataset from UCSC Xena database were analyzed. Consensus clustering analysis was conducted to identify OS-related molecular subtypes for GBM. The immune infiltrate level between subtypes were characterized by ESTIMATE algorithm. Differentially expressed genes (DEGs) between subtypes were screened by DESeq2 package. Two OS-related molecular subtypes of GBM were identified, and cluster 2 had poorer overall survival and higher immune infiltration levels than cluster 1. Enrichment analysis showed that 54 DEGs in cluster 2 were significantly enriched in cytokine/chemokine-related functions or pathways. Ten hub genes (CSF2, CSF3, CCL7, LCN2, CXCL6, MMP8, CCR8, TNFSF11, IL22RA2, and ORM1) were identified in GBM subtype 2 through protein-protein interaction network, most of which were positively correlated with immune factors and immune checkpoints. A total of 55 small molecule drugs obtained from drug gene interaction database (DGIdb) may have potential therapeutic effects in GBM subtype 2 patients. Our study identified 10 hub genes as potential therapeutic targets in GBM subtype 2 patients, who have poorer overall survival and higher immune infiltration levels. These findings could pave the way for new treatments for this aggressive form of brain cancer.

Parallelism and non-parallelism in diabetic nephropathy and diabetic retinopathy

Diabetic nephropathy (DN) and diabetic retinopathy (DR), as microvascular complications of diabetes mellitus, are currently the leading causes of end-stage renal disease (ESRD) and blindness, respectively, in the adult working population, and they are major public health problems with social and economic burdens. The parallelism between the two in the process of occurrence and development manifests in the high overlap of disease-causing risk factors and pathogenesis, high rates of comorbidity, mutually predictive effects, and partial concordance in the clinical use of medications. However, since the two organs, the eye and the kidney, have their unique internal environment and physiological processes, each with specific influencing molecules, and the target organs have non-parallelism due to different pathological changes and responses to various influencing factors, this article provides an overview of the parallelism and non-parallelism between DN and DR to further recognize the commonalities and differences between the two diseases and provide references for early diagnosis, clinical guidance on the use of medication, and the development of new drugs.

Longitudinal Profiling of Fasting Plasma Metabolome in Response to Weight-Loss Interventions in Patients with Morbid Obesity

It is well recognized that patients with severe obesity exhibit remarkable heterogeneity in response to different types of weight-loss interventions. Those who undergo Roux-en-Y gastric bypass (RYGB) usually exhibit more favorable glycemic outcomes than those who receive adjustable gastric banding (BAND) or intensive medical intervention (IMI). The molecular mechanisms behind these observations, however, remain largely unknown. To identify the plasma metabolites associated with differential glycemic outcomes induced by weight-loss intervention, we studied 75 patients with severe obesity (25 each in RYGB, BAND, or IMI). Using untargeted metabolomics, we repeatedly measured 364 metabolites in plasma samples at baseline and 1-year after intervention. Linear regression was used to examine whether baseline metabolites or changes in metabolites are associated with differential glycemic outcomes in response to different types of weight-loss intervention, adjusting for sex, baseline age, and BMI as well as weight loss. Network analyses were performed to identify differential metabolic pathways involved in the observed associations. After correction for multiple testing (q < 0.05), 33 (RYGB vs. IMI) and 28 (RYGB vs. BAND) baseline metabolites were associated with changes in fasting plasma glucose (FPG) or glycated hemoglobin (HbA1c). Longitudinal changes in 38 (RYGB vs. IMI) and 38 metabolites (RYGB vs. BAND) were significantly associated with changes in FPG or HbA1c. The identified metabolites are enriched in pathways involved in the biosynthesis of aminoacyl-tRNA and branched-chain amino acids. Weight-loss intervention evokes extensive changes in plasma metabolites, and the altered metabolome may underlie the differential glycemic outcomes in response to different types of weight-loss intervention, independent of weight loss itself.

Effect of Crocus sativus L. (saffron) and crocin in the treatment of patients with type-2 diabetes mellitus: A systematic review and meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Crocus sativus L. (saffron, Iridaceae) has been traditionally used for thousands of years as herbal medicine for many diseases, including type-2 diabetes mellitus (T2DM), especially in Sri Lanka. Systematic reviews and meta-analysis on C. sativus for T2DM value traditional knowledge about this species.

AIM OF THE STUDY

To assess the effectiveness of C. sativus powdered plant, hydroethanolic extract and crocin in reducing fasting blood sugar (FBG), glycated hemoglobin (HbA1c), blood pressure, and other metabolic parameters in patients with T2DM.

MATERIAL AND METHODS

Systematic review and meta-analysis based on searches in PubMed, Embase, and Cochrane, including all randomized clinical trials (RCTs) published before January 2, 2023. Two independent reviewers extracted the data and assessed the risks of bias. The effects of C. sativus and crocin were assessed on glycemic, metabolic, and blood pressure parameters. Weighted (WMD) or standardized (SMD) mean differences (before-after) and 95% confidence intervals (95%CI) of the outcomes were extracted or estimated and meta-analyses were conducted using RevMan 5.4 (Cochrane Collaboration). This protocol was registered in PROSPERO (#CRD42023390073).

RESULTS

Fifteen of 29 studies were included. Saffron powdered plant decreased AST (WMD -1.19, 95%CI -2.24, -0.13), but increased BMI (WMD 0.56, 95%CI 0.07, 1.05); saffron extract decreased HbA1c (WMD -0.35, 95%CI -0.65, -0.06), FBG (WMD -26.90, 95%CI -38.87, -14.93), creatinine (WMD -0.12, 95%CI -0.19, -0.05), and total cholesterol (WMD -9.29, 95%CI -18.25, -0.33); and crocin decreased HbA1c (WMD -0.43, 95%CI -0.66, -0.20), FBG (WMD -14.10, 95%CI -22.91, -5.30), and systolic blood pressure (WMD -8.18, 95%CI -12.75, -3.61), but increased creatinine levels (WMD 0.24, 95%CI 0.17, 0.32). Of the 15 included studies, 14 had a moderate risk of bias, and one study had a low risk of bias.

CONCLUSION

C. sativus (saffron) powdered plant, extract, and crocin have potential as an adjunct treatment for T2DM, improving control of metabolic and clinical parameters. However, C. sativus extract seems to be superior because it was effective in more parameters and did not induce adverse effects. Since many studies were at moderate risk of bias, further high-quality research is needed to firmly establish the clinical efficacy of this plant.

Ameliorating impact of coenzyme Q10 on the profile of adipokines, cardiomyopathy, and hematological markers correlated with the glucotoxicity sequelae in diabetic rats

BACKGROUND

In diabetes, high blood glucose induces glucotoxicity, resulting in the further damage of pancreatic beta-cells and then precipitating diabetic complications. This study was aimed to investigate the relationship between glucotoxicity with the level of adipokines, diabetic cardiomyopathy, and hematological markers. Moreover, the study examined the potential modulatory effect of coenzyme Q10 (CoQ10) on the aforementioned markers associated with the sequelae of diabetes mellitus.

MATERIAL AND METHODS

Twenty-four male rats were randomly assigned to receive an injection of STZ to induce diabetes (n = 16) or to remain uninduced (n = 8). The hyperglycemic status was induced in fasting rats by single intraperitoneal injection of STZ (45 mg /kg b.w.) dissolved in citrate buffer (pH 4.5). Three days after STZ injection, rats were divided into three groups; Normal control group (A), Diabetic control group (B), and CoQ10- treated diabetic group (C). The group (C) was fed with the basal diet supplemented with 5 g of CoQ10 per kilogram of diet for three weeks after the diabetes induction. After 21 days, the blood and serum samples were taken to conduct biochemical analyses. Blood glucose was determined by Blood Glucose Monitoring System. Adipokines or cytokines were evaluated by ELISA from a serum sample. Cardiac myopathy biomarkers were estimated by UP-Converting Phosphor Immunoassay Analyzer, and hematological parameters were measured by automatic hematology analyzer.

RESULTS

In hyperglycemic rats, the level of fasting blood glucose, and serum level of resistin, omentin, TNF-α, and cardiomyopathy biomarkers significantly increased (P < 0.05). The treatment with CoQ10 significantly decreased the profile of adipokines and cardiomyopathy markers (cardiac enzymes and LPPLA2) in diabetic rats and also reduced glucose levels (P < 0.05). Lymphocyte percentages significantly decreased while significant increases were observed in granulocytes and MID percentages in hyperglycemic rats.

CONCLUSION

Diabetic rats had higher serum levels of adipokines and cardiomyopathy markers. Among the hematological markers, GRA% and MID% increased while LYM% decreased. The profile of adipokines and cardiomyopathy markers improved when CoQ10 was supplemented. The study suggests that CoQ10 may have a beneficial effect on improving diabetic complications.

Antioxidant peptides, the guardian of life from oxidative stress

Reactive oxygen species (ROS) are produced during oxidative metabolism in aerobic organisms. Under normal conditions, ROS production and elimination are in a relatively balanced state. However, under internal or external environmental stress, such as high glucose levels or UV radiation, ROS production can increase significantly, leading to oxidative stress. Excess ROS production not only damages biomolecules but is also closely associated with the pathogenesis of many diseases, such as skin photoaging, diabetes, and cancer. Antioxidant peptides (AOPs) are naturally occurring or artificially designed peptides that can reduce the levels of ROS and other pro-oxidants, thus showing great potential in the treatment of oxidative stress-related diseases. In this review, we discussed ROS production and its role in inducing oxidative stress-related diseases in humans. Additionally, we discussed the sources, mechanism of action, and evaluation methods of AOPs and provided directions for future studies on AOPs.

Aubergine stem restores reproductive damages following diabetes mellitus induction in male mice

Diabetes mellitus unbalances cellular antioxidant levels. This phenomenon can potentially lead to cellular damage and apoptosis in the male reproductive system. Besides, herbal-based antioxidants can prevent these detrimental changes. Thus, we assessed the probable role of Aubergine stems with antioxidant and anti-hyperlipidemic characteristics on reproductive damage following diabetes mellitus induction. Forty male NMRI mice were categorized into groups of control and treatments. Diabetes was induced by a single dose of streptozotocin (60 mg/kg), and the extract was administered at various doses (100, 300, and 500 mg/kg) daily for 4 weeks. Antioxidative features of the extract were approved by phytochemical assays and ferric-reducing ability of plasma. Side-effects of diabetes were also assessed by the malondialdehyde (MDA) and Griess techniques. Sperm parameters, LH, FSH, and testosterone levels, the TUNEL assay, histopathologic alteration, and apoptotic genes (p53, caspase-3, Bcl-2) were evaluated. Results showed that diabetes increased oxidation levels and the extract accelerated total antioxidant capacity status. Sperm parameters and hormone levels were restored following extract administration in diabetic animals. Also, the apoptosis rate decreased following extract administration in diabetic animals. We concluded that diabetes can elevate the levels of oxidation and suppress the antioxidant power. These pathologic changes were restored by Aubergine stem, leading to decreased levels of apoptosis and normal serum levels of testosterone, LH, and FSH.

Gut-Gonad Perturbations in Type-1 Diabetes Mellitus: Role of Dysbiosis, Oxidative Stress, Inflammation and Energy-Dysbalance

Type 1 diabetes mellitus is a major metabolic disorder that affects people of all age groups throughout the world. It is responsible for the alterations in male gonadal physiology in experimental models as well as in clinical cases. On the other side, diabetes mellitus has also been associated with perturbations in the gut physiology and microbiota dysbiosis. The accumulating evidence suggests a link between the gut and gonad as evident from the i) experimental data providing insights into type 1 diabetes mellitus induced gut perturbations, ii) link of gut physiology with alterations of testicular health, iii) role of gut microbiota in androgen metabolism in the intestine, and iv) epidemiological evidence linking type 1 diabetes mellitus with inflammatory bowel disease and male infertility. Considering all the pieces of evidence, it is summarized that gut dysbiosis, oxidative stress, inflammation and energy dys-balance are the prime factors involved in the gonadal damage under type 1 diabetes mellitus, in which the gut contributes significantly. Identification of novel biomarkers and intervention of suitable agents targeting these prime factors may be a step forward to restore the gonadal damage in diabetic conditions.

Observation of the neuroprotective efficacy of vitamin K in a streptozocin-induced diabetes model in chick embryos

Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia due to insulin deficiency and/or resistance. Vitamin K (VK) is a group of fat-soluble molecules, including naturally occurring vitamin K1 (phylloquinone). vitamin K2 (menaquinone), and synthetic vitamin K3 (menadione). Beyond coagulation, the health benefits of VK have been described to play different roles in both physiological and pathological processes such as inflammation, energy metabolism, neuroprotection, cellular growth, and survival. It was aimed to observe the antioxidant and/or neuroprotective activity of vitamin K1 in our model of chick embryo diabetic neuropathy (DN) induced by streptozotocin (STZ). Ninety White Leghorn, fertile and 0-day-old SPF (specific pathogen-free) eggs (57 ± 4 gr) were used in the study. Chick embryo blood brain tissues were taken for biochemical evaluation. Plasma insulin and glucose levels were measured. In addition, brain tissue total antioxidant level (TAS), total oxidant level (TOS), malondialdehyde (MDA), and vascular endothelial growth factor (VEGF) levels were measured. Plasma glucose levels were higher in the STZ-treated groups and lower in the treatment groups. Plasma insulin levels were observed to be higher in STZ groups in groups treated with high VK. Low TAS, high MDA, TOS, and VEGF levels were recorded in brain tissue STZ groups. Low VEGF, TOS, and MDA levels were recorded in the group treated with the highest VK, while high TAS levels were observed. In our STZ-induced chick embryo diabetic neuropathy model, we observed that VK1 reduced oxidant damage by showing antioxidant properties or by modulating antioxidant enzymes.

In Vitro Hypoglycemic and Antioxidant Activities of Dichloromethane Extract of Xerophyta spekei

Diabetes mellitus is a chronic metabolic disorder which has greatly led to an increase in morbidity and mortality globally. Although Xerophyta spekei is widely used for the management of diabetes among the Embu and Mbeere communities in Kenya, it has never been empirically evaluated for its hypoglycemic activity. This study was carried out to verify the hypoglycemic activity of dichloromethane (DCM) extract of Xerophyta spekei as well as its antioxidant activity using various in vitro techniques. Phytochemicals associated with its antioxidant activity were identified through GC-MS. Data were subjected to descriptive statistics and expressed as mean ± standard error of the mean (X̄ ± SEM). Comparison between various variables was performed by using unpaired Student's t-test and one-way analysis of variance (ANOVA), followed by Tukey's post-hoc test. The confidence interval was set at 95%. The obtained results were presented in tables and graphs. Results showed that there was no difference in α-amylase inhibition activity between the plant extract and the standard (IC50 525.9 ± 12.34 and 475.1 ± 9.115, respectively; p  >  0.05). Besides, the glucose adsorption activity of the extract increased with an increase in glucose concentration (from 5.89 to 32.64 mg/dl at 5 mmol and 30 mmol of glucose, respectively; p  <  0.05). The extract also limited the diffusion of glucose more than the negative control (7.49 and 17.63 mg/dl, respectively; p  <  0.05). It also enhanced glucose uptake by yeast cells. In addition, the studied plant extract showed notable antioxidant activities. The therapeutic effects exhibited by this plant in managing diabetes mellitus and other ailments could be due to its antioxidant as well as its hypoglycemic activity. The study recommends the evaluation of X. spekei for in vivo hypoglycemic and antioxidant activities. Besides, the isolation of bioactive phytochemicals from the plant may lead to the development of new hypoglycaemic agents.

From diabetic hyperglycemia to cerebrovascular Damage: A narrative review

Diabetes mellitus is a globally significant disease that can lead to systemic complications, particularly vascular damage, including cardiovascular and cerebrovascular diseases of relevance. The physiological changes resulting from the imbalance in blood glucose levels play a crucial role in initiating vascular endothelial damage. Elevated glucose levels can also penetrate the central nervous system, triggering diabetic encephalopathy characterized by oxidative damage to brain components and activation of alternative and neurotoxic pathways. This brain damage increases the risk of ischemic stroke, a leading cause of mortality worldwide and a major cause of disability among surviving patients. The aim of this review is to highlight important pathways related to hyperglycemic damage that extend to the brain and result in vascular dysfunction, ultimately leading to the occurrence of a stroke. Understanding how diabetes mellitus contributes to the development of ischemic stroke and its impact on patient outcomes is crucial for implementing therapeutic strategies that reduce the incidence of diabetes mellitus and its complications, ultimately decreasing morbidity and mortality associated with the disease.

Glycemic variability leads to higher levels of auto-oxidized oxysterol species in patients with type 1 diabetes mellitus

PURPOSE

Hyperglycemia and glycemic variability (GV) are associated with oxidative stress in patients with diabetes mellitus (DM). Oxysterol species, produced by the non-enzymatic oxidation of cholesterol, are potential biomarkers of oxidative stress. This study examined the relationship between auto-oxidized oxysterols and GV in patients with type 1 DM.

METHODS

Thirty patients with type 1 DM using a continuous subcutaneous insulin infusion pump therapy and a healthy control group (n = 30) were included in this prospective study. A Continuous Glucose Monitoring System device was applied for 72 h. Blood samples were taken for oxysterols produced by non-enzymatic oxidation [7-ketocholesterol (7-KC) and cholestane-3β, 5α, 6β-triol (Chol-Triol)] levels at 72 h. Short-term glycemic variability parameters, mean amplitude of glycemic excursions (MAGE), the standard deviation of glucose measurements (Glucose-SD), and mean of daily differences (MODD) were calculated with continuous glucose monitoring data. HbA1c was used to evaluate glycemic control and HbA1c-SD (the SD of HbA1c over the past year) for long-term glycemic variability.

RESULTS

7-KC and Chol-triol levels were significantly higher in the study group than in the control group. Strong positive correlations were found between 7-KC with MAGE(24-48 h) and Glucose-SD(24-48 h). 7-KC was positively correlated with MAGE(0-72 h) and Glucose-SD(0-72 h). No significant correlation was found between HbA1c and HbA1c -SD with oxysterol levels. The regression models showed that SD(24-48 h) and MAGE(24-48 h) predicted 7-KC levels while HbA1c did not.

CONCLUSIONS

Glycemic variability leads to higher levels of auto-oxidized oxysterol species in patients with type 1 DM independent of long-term glycemic control.

Potential therapeutic value of melatonin in diabetic nephropathy: improvement beyond anti-oxidative stress

Diabetic nephropathy (DN) is a common complication of diabetes, and it is also the main cause of chronic renal failure. Physiological/pathological changes mediated by high glucose are the main factors causing injury of DN, including the enhancement of polyol pathway, the accumulation of advanced glycation products (AGEs), and the activation of protein kinase C (PKC) and transforming growth factor-β (TGF-β) signals. In addition, the abnormal activation of renin-angiotensin system (RAS) and oxidative stress are also involved. Melatonin is a physiological hormone mainly secreted by the pineal gland which has been proved to be related to diabetes. Studies have shown that exogenous melatonin intervention can reduce blood glucose and alleviate high glucose mediated pathological damage. At the same time, melatonin also has a strong antioxidant effect, and can inhibit the activation of RAS. Therefore, it is of great significance to explore the therapeutic effect and value of melatonin on DN.

Mango (Mangifera indica L.) seed kernel extract suppresses hyperglycemia by modulating pancreatic β cell apoptosis and dysfunction and hepatic glucose metabolism in diabetic rats

This study investigated the anti-hyperglycemic action of mango seed kernel extract (MKE) and various mechanisms involved in its actions to improve pancreatic β cells and hepatic carbohydrate metabolism in diabetic rats. An intraperitoneal injection of 60 mg/kg of streptozotocin (STZ) followed by 30 consecutive days of treatment with MKE (250, 500, and 1000 mg/kg body weight) was used to establish a study group of diabetic rats. Using liquid chromatography-electrospray ionization-quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS/MS) for identification, 26 chemical compounds were found in MKE and the high-performance liquid chromatography (HPLC) analysis of the MKE also revealed the existence of mangiferin, gallic acid, and quercetin. The results confirmed that in each diabetes-affected rat, MKE mitigated the heightened levels of fasting blood glucose, diabetic symptoms, glucose intolerance, total cholesterol (TC), and low-density lipoprotein-cholesterol (LDL-C). As demonstrated by a remarkable increment in serum and pancreatic insulin, the diabetic pancreatic β cell function was potentiated by treating with MKE. The effect of MKE on diabetic pancreatic apoptosis clearly reduced the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells, which was related to diminished levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and Bax and an increase in Bcl-xL protein expression. Furthermore, diabetes-induced liver damage was clearly ameliorated along with a notable reduction in serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels and abnormal liver histology. By enhancing anti-oxidant superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities, MKE alleviated diabetes-induced pancreatic and liver oxidative damage, as demonstrated by diminished levels of malondialdehyde. In minimizing the expression levels of glucose 6-phosphatase and phosphoenolpyruvate carboxykinase-1 proteins in the diabetic liver, MKE also enhanced glycogen content and hexokinase activity. Collectively, these findings indicate that by suppressing oxidative and inflammatory processes, MKE exerts a potent anti-hyperglycemic activity in diabetic rats which serve to protect pancreatic β cell apoptosis, enhance their function, and improve hepatic glucose metabolism.

Exosomes derived from platelet-rich plasma promote diabetic wound healing via the JAK2/STAT3 pathway

Diabetic non-healing wounds are bringing a heavy burden on patients and society. Platelet-rich plasma (PRP) has been widely applied in tissue regenerating for containing various growth factors. Recently, PRP-derived exosomes (PRP-Exos) have been proved to be more effective than PRP in tissue regeneration. However, few studies have investigated the therapeutic potential of PRP-Exos in diabetic wound healing to date. Therefore, we extracted and identified exosomes derived from PRP and tested its promoting effect on diabetic wound healing in vivo and in vitro. We found that high glucose (HG) inhibited cell proliferation and migration and induced apoptosis through ROS-dependent activation of the JNK and p38 MAPK signaling pathways. PRP-Exos can stimulate fibroblast functions and accelerate diabetic wound healing. The benefits of PRP-Exos may be attributed to its capability to prevent HG-induced ROS-dependent apoptosis via the PDGF-BB/JAK2/STAT3/Bcl-2 signaling pathway. This illustrates the therapeutic potential of PRP-Exos in diabetic wounds.

Oxidative stress, epigenetic regulation and pathological processes of lens epithelial cells underlying diabetic cataract

Background

Cataract is a blinding disease worldwide. It is an age-related disease that mainly occurs in people over 65 years old. Cataract is also prevalent in patients with diabetes mellites (DM). The pathological mechanisms underlying diabetic cataract (DC) are more complex than that of age-related cataract. Studies have identified that polyol pathway, advanced glycation end products (AGEs) and oxidative stress are the primary pathogenesis of DC. In recent years, molecular-level regulations and pathological processes of lens epithelial cells (LECs) have been confirmed to play roles in the initiation and progression of DC. A comprehensive understanding and elucidation of how chronic hyperglycemia drives molecular-level regulations and cytopathological processes in the lens will shed lights on the prevention, delay and treatment of DC.

Main text

Excessive glucose in the lens enhances polyol pathway and AGEs formation. Polyol pathway causes imbalance in the ratio of NADPH/NADP+ and NADH/NAD+. Decrease in NADPH/NADP+ ratio compromises antioxidant enzymes, while increase in NADH/NAD+ ratio promotes reactive oxygen species (ROS) overproduction in mitochondria, resulting in oxidative stress. Oxidative stress in the lens causes oxidation of DNA, proteins and lipids, leading to abnormalities in their structure and functions. Glycation of proteins by AGEs decreases solubility of proteins. High glucose triggered epigenetic regulations directly or indirectly affect expressions of genes and proteins in LECs. Changes in autophagic activity, increases in fibrosis and apoptosis of LECs destroy the morphological structure and physiological functions of the lens epithelium, disrupting lens homeostasis.

Conclusions

In both diabetic animal models and diabetics, oxidative stress plays crucial roles in the formation of cataract. Epigenetic regulations, include lncRNA, circRNA, microRNA, methylation of RNA and DNA, histone acetylation and pathological processes, include autophagy, fibrosis and apoptosis of LECs also involved in DC.

New insights into anti-diabetes effects and molecular mechanisms of dietary saponins

Diabetes mellitus (DM) is a long-term metabolic disorder that manifests as chronic hyperglycemia and impaired insulin, bringing a heavy load on the global health care system. Considering the inevitable side effects of conventional anti-diabetic drugs, saponins-rich natural products exert promising therapeutic properties to serve as safer and more cost-effective alternatives for DM management. Herein, this review systematically summarized the research progress on the anti-diabetic properties of dietary saponins and their underlying molecular mechanisms in the past 20 years. Dietary saponins possessed the multidirectional anti-diabetic capabilities by concurrent regulation of various signaling pathways, such as IRS-1/PI3K/Akt, AMPK, Nrf2/ARE, NF-κB-NLRP3, SREBP-1c, and PPARγ, in liver, pancreas, gut, and skeletal muscle. However, the industrialization and commercialization of dietary saponin-based drugs are confronted with a significant challenge due to the low bioavailability and lack of the standardization. Hence, in-depth evaluations in pharmacological profile, function-structure interaction, drug-signal pathway interrelation are essential for developing dietary saponins-based anti-diabetic treatments in the future.

Common mechanisms underlying diabetic vascular complications: focus on the interaction of metabolic disorders, immuno-inflammation, and endothelial dysfunction

Diabetic vascular complications (DVCs), including macro- and micro- angiopathy, account for a high percentage of mortality in patients with diabetes mellitus (DM). Endothelial dysfunction is the initial and role step for the pathogenesis of DVCs. Hyperglycemia and lipid metabolism disorders contribute to endothelial dysfunction via direct injury of metabolism products, crosstalk between immunity and inflammation, as well as related interaction network. Although physiological and phenotypic differences support their specified changes in different targeted organs, there are still several common mechanisms underlying DVCs. Also, inhibitors of these common mechanisms may decrease the incidence of DVCs effectively. Thus, this review may provide new insights into the possible measures for the secondary prevention of DM. And we discussed the current limitations of those present preventive measures in DVCs research. Video Abstract.

Recent Trends in the Antidiabetic Prominence of Natural and Synthetic Analogues of Aurones

Natural products are a boundless source for the development of pharmaceutical agents against a wide range of human diseases. Accordingly, naturally occurring aurones possess various biological benefits, such as anticancer, antioxidant, antimicrobial, antidiabetic, anti-inflammatory, antiviral and neuroprotective effects. In addition, various studies have revealed that aurones are potential templates for the regulation of diabetes mellitus and its associated complications. Likewise, certain aurones and their analogues have been found to be remarkable kinase inhibitors of DARK2, PPAR-γ, PTPM1, AGE, α-amylase and α-glucosidase, which represents a promising approach for the treatment of chronic metabolic disorders such as diabetes. Therefore, in our present study, we provide a detailed account of the advances in aurones as antidiabetic agents over the past decade.

Mollugin activates GLP-1R to improve cognitive dysfunction in type 2 diabetic mice

AIMS

The incidence of diabetic cognitive dysfunction is increasing year by year, and it has gradually become a research hot spot. Studies have shown that glucagon-like peptide-1 receptor (GLP-1R) agonists can improve cognitive dysfunction in diabetic patients. This study focuses on whether small molecule GLP-1R agonists from traditional Chinese medicine (TCM) can improve the diabetic cognitive dysfunction.

MATERIALS AND METHODS

The small molecules from TCM were screened by cell membrane chromatography (CMC) with GLP-1R-HEK293 cell membrane column. MTT assay, flow cytometry, immunofluorescence cytochemistry and other methods were used to determine the effects of mollugin on the apoptosis rate and reactive oxygen species (ROS) level of high glucose (HG)/hydrogen peroxide (H2O2) induced PC12 cells. Real-Time PCR was used to detect mRNA expression in mouse cerebral cortex. Water maze test was further used to confirm the effect of mollugin on cognitive dysfunction in T2DM mice.

KEY FINDINGS

Mollugin bound to GLP-1R, promoted Ca2+ influx, increased insulin secretion and cAMP content in β-TC-6 cells. Mollugin enhanced the cell viability, ameliorated apoptosis, reduced intracellular ROS levels in HG/H2O2-injured PC12 cells. Mollugin reduced the T2DM mice's escape latency, improved neuronal cell damage, decreased the expression of Pik3ca, Akt1 and Mapk1 mRNA in the cerebral cortex tissue.

SIGNIFICANCE

The results suggest that mollugin could improve cognitive dysfunction in T2DM mice through activating GLP-1R/cAMP/PKA signal pathway.

Oxidative Stress Biomarkers in Cystic Fibrosis and Cystic Fibrosis-Related Diabetes in Children: A Literature Review

The most common inherited condition that results in death, particularly in those of Caucasian heritage, is cystic fibrosis (CF). Of all the young adults diagnosed with cystic fibrosis, 20% will develop hyperglycemia as a complication, later classified as a disease associated with cystic fibrosis. Impaired insulin secretion and glucose intolerance represent the primary mechanisms associated with diabetes (type 1 or type 2) and cystic fibrosis. Oxidative stress represents the imbalance between oxygen-reactive species and antioxidant defense mechanisms. This pathogenic mechanism is vital in triggering other chronic diseases, including cystic fibrosis-related diabetes. It is essential to understand oxidative stress and the significant impact it has on CFRD. This way, therapies can be individually adjusted and tailored to each patient's needs. This review aims to understand the connection between CFRD and oxidative stress. As a subsidiary element, we analyzed the effects of glycemic balance on complications and their evolution over time, providing insights into their potential benefits in mitigating oxidative stress-associated complications.

Hippophae rhamnoides L. leaf extracts alleviate diabetic nephropathy via attenuation of advanced glycation end product-induced oxidative stress in db/db mice

Diabetes mellitus leads to chronic complications, such as nephropathy. Diabetic complications are closely related to advanced glycation end products (AGEs). Excessive formation and accumulation of AGEs in diabetic renal diseases lead to excessive oxidative stress, resulting in chronic renal failure. The leaves of Hippophae rhamnoides L. (sea buckthorn leaves; SBL) show biological benefits, including antioxidant effects. This study aimed to evaluate the effect of SBL on kidney damage in db/db mice. The SBL extract was orally administered at 100 and 200 mg kg-1 for 12 weeks to db/db mice. Histological changes and the urine albumin/creatinine ratio were relieved, and the accumulation of AGEs in kidney glomeruli decreased following SBL treatment. Moreover, the SBL extract reduced the expression of AGEs, the receptor for AGEs, and NADPH oxidase 4, but upregulated glyoxalase 1 in the diabetic renal tissue. Urinary excretion levels and expression of 8-hydroxy-2'-deoxyguanosine as a biomarker of oxidative stress decreased after SBL treatment in the renal tissue. Furthermore, SBL attenuated oxidative stress in diabetic kidneys by reducing AGE accumulation, thereby ameliorating renal damage. Therefore, from these results, we infer that the SBL extract can act as a potential therapeutic agent for diabetic renal complications caused by AGEs.

Mechanism of Escherichia coli Lethality Caused by Overexpression of flhDC, the Flagellar Master Regulator Genes, as Revealed by Transcriptome Analysis

The flhDC operon of Escherichia coli encodes a transcription factor that initiates flagella synthesis, elevates flagella construction and enhances cell motility, which all are energetically costly and highly regulated processes. In this study, we found that overexpression of flhDC genes from a strong regulatable pN15E6 plasmid could inhibit the growth of E. coli host cells and even eventually cause death. We used transcriptome analysis to investigate the mechanism of flhDC overexpression lethal to host bacteria. The results showed that a total of 568 differentially expressed genes (DEGs), including 378 up-regulated genes and 190 down-regulated genes were detected when the flhDC genes were over-expressed. Functional enrichment analysis results showed that the DEGs are related to a series of crucial biomolecular processes, including flagella synthesis, oxidative phosphorylation and pentose phosphate pathways, etc. We then examined, using RT-qPCR, the expression of key genes of the oxidative phosphorylation pathway at different time points after induction. Results showed that their expression increased in the early stage and decreased afterward, which was suggested to be the result of feedback on the overproduction of ROS, a strong side effect product of the elevated oxidative phosphorylation process. To further verify the level of ROS output, flhDC over-expressed bacteria cells were stained with DCHF-DA and a fluorescence signal was detected using flow cytometry. Results showed that the level of ROS output was higher in cells with over-expressed flhDC than in normal controls. Besides, we found upregulation of other genes (recN and zwf) that respond to ROS damage. This leads to the conclusion that the bacterial death led by the overexpression of flhDC genes is caused by damage from ROS overproduction, which leaked from the oxidative phosphorylation pathway.