Glucose and reactive oxygen species

Role of inflammation in diabetic macular edema and neovascular age-related macular degeneration

Diabetic macular edema (DME) and neovascular age-related macular degeneration (nAMD) are multifactorial disorders that affect the macula and cause significant vision loss. Although inflammation and neoangiogenesis are hallmarks of DME and nAMD, respectively, they share some biochemical mediators. While inflammation is a trigger for the processes that lead to the development of DME, in nAMD inflammation seems to be the consequence of retinal pigment epithelium and Bruch membrane alterations. These pathophysiologic differences may be the key issue that justifies the difference in treatment strategies. Vascular endothelial growth factor inhibitors have changed the treatment of both diseases, however, many patients with DME fail to achieve the established therapeutic goals. From a clinical perspective, targeting inflammatory pathways with intravitreal corticosteroids has been proven to be effective in patients with DME. On the contrary, the clinical relevance of addressing inflammation in patients with nAMD has not been proven yet. We explore the role and implication of inflammation in the development of nAMD and DME and its therapeutical relevance.

Making bloodwork work: the impact of sample collection, processing, and storage on plasma glutathione measurement, and implications for translation

Psychiatry has traditionally focused on the study of neurons and neurotransmitter physiology in the pathophysiology and treatment of psychiatric disorders. A growing literature highlights REDOX imbalance (a state in which demand for antioxidants surpasses their bioavailability) as a common pathophysiology for a diverse array of brain conditions (e.g., trichotillomania, schizophrenia, autism, Parkinson's disease). REDOX imbalance is typically measured via plasma glutathione, as glutathione is critical to the adaptive antioxidant response in the brain. Accordingly, glutathione, its precursors, and/or metabolites serve as biomarkers of disease risk, therapeutic targets, and measures of treatment response. However, as with any emerging field, there are currently several different methods for collection, processing, storage, and calculation of summary measures of plasma glutathione metabolism, within and between preclinical and clinical research. The lack of evidence-based best-practice methodology hampers reproducibility (preclinical or clinical), and translation (between preclinical and clinical work). To address this methodological need, here we used a repeated measures within-subject design to investigate how sample preparation (type of anticoagulant used during blood collection, deproteinization status, and storage temperature) affects plasma glutathione levels. Accordingly, we collected whole blood from mice (N = 13), and then, using a commercially available kit, quantified glutathione in plasma stored in four different ways. Presuming that these preparation conditions and post-processing calculations are unimportant, we would expect to see no difference in glutathione levels and summary measures from the same sample. However, we found each of these variables to significantly alter quantified glutathione levels. Accordingly, we propose a vital, gold-standard methodology for both sample collection, processing, and storage of plasma used for glutathione quantification and for summary calculations of glutathione that can be used preclinically and clinically, thus yielding more streamlined translation.

The relationship of redox signaling with the risk for atherosclerosis

Oxidative balance plays a pivotal role in physiological homeostasis, and many diseases, particularly age-related conditions, are closely associated with oxidative imbalance. While the strategic role of oxidative regulation in various diseases is well-established, the specific involvement of oxidative stress in atherosclerosis remains elusive. Atherosclerosis is a chronic inflammatory disorder characterized by plaque formation within the arteries. Alterations in the oxidative status of vascular tissues are linked to the onset, progression, and outcome of atherosclerosis. This review examines the role of redox signaling in atherosclerosis, including its impact on risk factors such as dyslipidemia, hyperglycemia, inflammation, and unhealthy lifestyle, along with dysregulation, vascular homeostasis, immune system interaction, and therapeutic considerations. Understanding redox signal transduction and the regulation of redox signaling will offer valuable insights into the pathogenesis of atherosclerosis and guide the development of novel therapeutic strategies.

Effects of Berberis vulgaris fruit extract on oxidative stress status in the kidney and liver of diabetic rats

OBJECTIVES

Oxidative stress has a key role in the diabetes pathogenesis and complications. Berberis vulgaris is known in folk medicine for curing several diseases. The current research aimed to assess the influences of Berberis vulgaris fruit extract against oxidative stress in streptozotocin-induced diabetic rats.

METHODS

Streptozotocin (60 mg/kg, ip) was injected to male rats. After diabetes confirmation, animals received the Berberis vulgaris fruit extract daily at amounts of 3.5 and 7.5 % of drinking water (v/v) for six weeks. Total thiol and lipid peroxidation levels were assessed in the serum, liver, kidney and spleen at the end of the study.

RESULTS

Diabetic rats exhibited hyperglycemia along with enhancement of lipid peroxidation levels in the serum, liver, kidney and spleen, and decrement of total thiol content in the kidney and liver tissues. Chronic administration of Berberis vulgaris fruit extract at amount of 3.5 % of drinking water decreased the lipid peroxidation level in the serum and liver, and enhanced total thiol level in the liver and kidney.

CONCLUSIONS

Berberis vulgaris fruit extract exerts antioxidant activity in the serum, liver and kidney organs of diabetic rats. Therefore, it might be used in the prevention and control of diabetes complications.

Assessing the influence of preconception diet on male fertility: a systematic scoping review

BACKGROUND

The last decade has seen increased research on the relationship between diet and male fertility, but there are no clearly defined nutritional recommendations for men in the preconception period to support clinical fertility outcomes.

OBJECTIVE AND RATIONALE

The purpose of this scoping review is to examine the extent and range of research undertaken to evaluate the effect(s) of diet in the preconception period on male clinical fertility and reproductive outcomes.

SEARCH METHODS

Four electronic databases (MEDLINE and EMBASE via Ovid, CAB Direct, and CINAHL via EBSCO) were searched from inception to July 2023 for randomized controlled trials (RCTs) and observational studies (prospective/retrospective, case-control, and cross-sectional). Intervention studies in male participants or couples aiming to achieve dietary or nutritional change, or non-intervention studies examining dietary or nutritional components (whole diets, dietary patterns, food groups or individual foods) in the preconception period were included. Controls were defined as any comparison group for RCTs, and any/no comparison for observational studies. Primary outcomes of interest included the effect(s) of male preconception diet on clinical outcomes such as conception (natural or via ART), pregnancy rates and live birth rates. Secondary outcomes included time to conception and sperm parameters.

OUTCOMES

A total of 37 studies were eligible, including one RCT and 36 observational studies (prospective, cross-sectional, and case-control studies; four studies in non-ART populations) published between 2008 and 2023. Eight reported clinical outcomes, 26 reported on secondary outcomes, and three reported on both. The RCT did not assess clinical outcomes but found that tomato juice may benefit sperm motility. In observational studies, some evidence suggested that increasing fish or reducing sugar-sweetened beverages, processed meat or total fat may improve fecundability. Evidence for other clinical outcomes, such as pregnancy rates or live birth rates, showed no relationship with cereals, soy and dairy, and inconsistent relationships with consuming red meat or a 'healthy diet' pattern. For improved sperm parameters, limited evidence supported increasing fish, fats/fatty acids, carbohydrates and dairy, and reducing processed meat, while the evidence for fruits, vegetables, cereals, legumes, eggs, red meat and protein was inconsistent. Healthy diet patterns in general were shown to improve sperm health.

WIDER IMPLICATIONS

Specific dietary recommendations for improving male fertility are precluded by the lack of reporting on clinical pregnancy outcomes, heterogeneity of the available literature and the paucity of RCTs to determine causation or to rule out reverse causation. There may be some benefit from increasing fish, adopting a healthy dietary pattern, and reducing consumption of sugar-sweetened beverages and processed meat, but it is unclear whether these benefits extend beyond sperm parameters to improve clinical fertility. More studies exploring whole diets rather than singular foods or nutritional components in the context of male fertility are encouraged, particularly by means of RCTs where feasible. Further assessment of core fertility outcomes is warranted and requires careful planning in high-quality prospective studies and RCTs. These studies can lay the groundwork for targeted dietary guidelines and enhance the prospects of successful fertility outcomes for men in the preconception period. Systematic search of preconception diet suggests that increasing fish and reducing sugary drinks, processed meats and total fat may improve male fertility, while consuming healthy diets, fish, fats/fatty acids, carbohydrates and dairy and reducing processed meat can improve sperm health.

Evaluation of the effects of dietary advanced glycation end products on inflammation

Advanced glycation end products (AGEs) are a large number of heterogeneous compounds formed by the glycation of proteins, fats or nucleic acids. Endogenous AGEs have been associated with various health problems such as obesity, type 2 diabetes mellitus and cardiovascular disease. Inflammation is thought to be one of the main mechanisms in the development of these disorders. Although AGEs are produced endogenously in the body, exogenous sources such as smoking and diet also contribute to the body pool. Therefore, when the AGE pool in the body rises above physiological levels, different pathological conditions may occur through various mechanisms, especially inflammation. While the effects of endogenous AGEs on the development of inflammation have been studied relatively extensively, and current evidence indicates that dietary AGEs (dAGEs) contribute to the body's AGE pool, it is not yet known whether dAGEs have the same effect on the development of inflammation as endogenous AGEs. Therefore, this review aimed to evaluate the results of cross-sectional and intervention studies to understand whether dAGEs are associated with inflammation and, if there is an effect on inflammation, through which mechanisms this effect might occur.

Advances in oxidative stress in pathogenesis of diabetic kidney disease and efficacy of TCM intervention

Diabetic kidney disease (DKD) is a common complication of diabetes and has become the leading cause of end-stage kidney disease. The pathogenesis of DKD is complicated, and oxidative stress is considered as a core of DKD onset. High glucose can lead to increased production of reactive oxygen species (ROS) via the polyol, PKC, AGE/RAGE and hexosamine pathways, resulting in enhanced oxidative stress response. In this way, pathways such as PI3K/Akt, TGF-β1/p38-MAPK and NF-κB are activated, inducing endothelial cell apoptosis, inflammation, autophagy and fibrosis that cause histologic and functional abnormalities of the kidney and finally result in kidney injury. Presently, the treatment for DKD remains an unresolved issue. Traditional Chinese medicine (TCM) has unique advantages for DKD prevention and treatment attributed to its multi-target, multi-component, and multi-pathway characteristics. Numerous studies have proved that Chinese herbs (e.g., Golden Thread, Kudzuvine Root, Tripterygium glycosides, and Ginseng) and patent medicines (e.g., Shenshuaining Tablet, Compound Rhizoma Coptidis Capsule, and Zishen Tongluo Granule) are effective for DKD treatment. The present review described the role of oxidative stress in DKD pathogenesis and the effect of TCM intervention for DKD prevention and treatment, in an attempt to provide evidence for clinical practice.

Emerging therapeutic options in the management of diabetes: recent trends, challenges and future directions

Diabetes is a serious health issue that causes a progressive dysregulation of carbohydrate metabolism due to insufficient insulin hormone, leading to consistently high blood glucose levels. According to the epidemiological data, the prevalence of diabetes has been increasing globally, affecting millions of individuals. It is a long-term condition that increases the risk of various diseases caused by damage to small and large blood vessels. There are two main subtypes of diabetes: type 1 and type 2, with type 2 being the most prevalent. Genetic and molecular studies have identified several genetic variants and metabolic pathways that contribute to the development and progression of diabetes. Current treatments include gene therapy, stem cell therapy, statin therapy, and other drugs. Moreover, recent advancements in therapeutics have also focused on developing novel drugs targeting these pathways, including incretin mimetics, SGLT2 inhibitors, and GLP-1 receptor agonists, which have shown promising results in improving glycemic control and reducing the risk of complications. However, these treatments are often expensive, inaccessible to patients in underdeveloped countries, and can have severe side effects. Peptides, such as glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1), are being explored as a potential therapy for diabetes. These peptides are postprandial glucose-dependent pancreatic beta-cell insulin secretagogues and have received much attention as a possible treatment option. Despite these advances, diabetes remains a major health challenge, and further research is needed to develop effective treatments and prevent its complications. This review covers various aspects of diabetes, including epidemiology, genetic and molecular basis, and recent advancements in therapeutics including herbal and synthetic peptides.

Flavonols as a Potential Pharmacological Intervention for Alleviating Cognitive Decline in Diabetes: Evidence from Preclinical Studies

Diabetes mellitus is a complex metabolic disease associated with reduced synaptic plasticity, atrophy of the hippocampus, and cognitive decline. Cognitive impairment results from several pathological mechanisms, including increased levels of advanced glycation end products (AGEs) and their receptors, prolonged oxidative stress and impaired activity of endogenous mechanisms of antioxidant defense, neuroinflammation driven by the nuclear factor kappa-light-chain enhancer of activated B cells (NF-κB), decreased expression of brain-derived neurotrophic factor (BDNF), and disturbance of signaling pathways involved in neuronal survival and cognitive functioning. There is increasing evidence that dietary interventions can reduce the risk of various diabetic complications. In this context, flavonols, a highly abundant class of flavonoids in the human diet, are appreciated as a potential pharmacological intervention against cognitive decline in diabetes. In preclinical studies, flavonols have shown neuroprotective, antioxidative, anti-inflammatory, and memory-enhancing properties based on their ability to regulate glucose levels, attenuate oxidative stress and inflammation, promote the expression of neurotrophic factors, and regulate signaling pathways. The present review gives an overview of the molecular mechanisms involved in diabetes-induced cognitive dysfunctions and the results of preclinical studies showing that flavonols have the ability to alleviate cognitive impairment. Although the results from animal studies are promising, clinical and epidemiological studies are still needed to advance our knowledge on the potential of flavonols to improve cognitive decline in diabetic patients.

Rubia cordifolia L. Attenuates Diabetic Neuropathy by Inhibiting Apoptosis and Oxidative Stress in Rats

BACKGROUND

Diabetic neuropathy is a debilitating manifestation of long-term diabetes mellitus. The present study explored the effects of the roots of Rubia cordifolia L. (R. cordifolia L.) in the Wistar rat model for diabetic neuropathy and possible neuroprotective, antidiabetic, and analgesic mechanisms underlying this effect.

MATERIALS AND METHODS

Rats were divided into five experimental groups. An amount of 0.25% carboxy methyl cellulose (CMC) in saline and streptozotocin (STZ) (60 mg/kg) was given to group 1 and group 2, respectively. Group 3 was treated with STZ and glibenclamide simultaneously while groups 4 and 5 were simultaneously treated with STZ and hydroalcoholic extract of the root of R. cordifolia, respectively. Hot plate and cold allodynias were used to evaluate the pain threshold. The antioxidant effects of R. cordifolia were assessed by measuring Thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD). At the end of the study, sciatic nerve and brain tissues were collected for histopathological study. Bcl-2 proteins, cleaved caspase-3, and Bax were assessed through the Western blot method.

RESULTS

R. cordifolia significantly attenuated paw withdrawal and tail flick latency in diabetic neuropathic rats. R. cordifolia significantly (p < 0.01) improved the levels of oxidative stress. It was found to decrease blood glucose levels and to increase animal weight in R. cordifolia-treated groups. Treatment with R. cordifolia suppressed the cleaved caspase-3 and reduced the Bax:Bcl2 ratio in sciatic nerve and brain tissue compared to the diabetic group. Histopathological analysis also revealed a marked improvement in architecture and loss of axons in brain and sciatic nerve tissues at a higher dose of R. cordifolia (400 mg/kg).

CONCLUSION

R. cordifolia attenuated diabetic neuropathy through its antidiabetic and analgesic properties by ameliorating apoptosis and oxidative stress.

The Role of Iron Overload in Diabetic Cognitive Impairment: A Review

It is well documented that diabetes mellitus (DM) is strongly associated with cognitive decline and structural damage to the brain. Cognitive deficits appear early in DM and continue to worsen as the disease progresses, possibly due to different underlying mechanisms. Normal iron metabolism is necessary to maintain normal physiological functions of the brain, but iron deposition is one of the causes of some neurodegenerative diseases. Increasing evidence shows that iron overload not only increases the risk of DM, but also contributes to the development of cognitive impairment. The current review highlights the role of iron overload in diabetic cognitive impairment (DCI), including the specific location and regulation mechanism of iron deposition in the diabetic brain, the factors that trigger iron deposition, and the consequences of iron deposition. Finally, we also discuss possible therapies to improve DCI and brain iron deposition.

Advanced glycation end products: Key mediator and therapeutic target of cardiovascular complications in diabetes

The incidence of type 2 diabetes mellitus is growing in epidemic proportions and has become one of the most critical public health concerns. Cardiovascular complications associated with diabetes are the leading cause of morbidity and mortality. The cardiovascular diseases that accompany diabetes include angina, myocardial infarction, stroke, peripheral artery disease, and congestive heart failure. Among the various risk factors generated secondary to hyperglycemic situations, advanced glycation end products (AGEs) are one of the important targets for future diagnosis and prevention of diabetes. In the last decade, AGEs have drawn a lot of attention due to their involvement in diabetic patho-physiology. AGEs can be derived exogenously and endogenously through various pathways. These are a non-homogeneous, chemically diverse group of compounds formed non-enzymatically by condensation between carbonyl groups of reducing sugars and free amino groups of protein, lipids, and nucleic acid. AGEs mediate their pathological effects at the cellular and extracellular levels by multiple pathways. At the cellular level, they activate signaling cascades via the receptor for AGEs and initiate a complex series of intracellular signaling resulting in reactive oxygen species generation, inflammation, cellular proliferation, and fibrosis that may possibly exacerbate the damaging effects on cardiac functions in diabetics. AGEs also cause covalent modifications and cross-linking of serum and extracellular matrix proteins; altering their structure, stability, and functions. Early diagnosis of diabetes may prevent its progression to complications and decrease its associated comorbidities. In the present review, we recapitulate the role of AGEs as a crucial mediator of hyperglycemia-mediated detrimental effects in diabetes-associated complications. Furthermore, this review presents an overview of future perspectives for new therapeutic interventions to ameliorate cardiovascular complications in diabetes.

Eco-friendly chitosan-based nanostructures in diabetes mellitus therapy: Promising bioplatforms with versatile therapeutic perspectives

Nature-derived polymers, or biopolymers, are among the most employed materials for the development of nanocarriers. Chitosan (CS) is derived from the acetylation of chitin, and this biopolymer displays features such as biocompatibility, biodegradability, low toxicity, and ease of modification. CS-based nano-scale delivery systems have been demonstrated to be promising carriers for drug and gene delivery, and they can provide site-specific delivery of cargo. Owing to the high biocompatibility of CS-based nanocarriers, they can be used in the future in clinical trials. On the other hand, diabetes mellitus (DM) is a chronic disease that can develop due to a lack of insulin secretion or insulin sensitivity. Recently, CS-based nanocarriers have been extensively applied for DM therapy. Oral delivery of insulin is the most common use of CS nanoparticles in DM therapy, and they improve the pharmacological bioavailability of insulin. Moreover, CS-based nanostructures with mucoadhesive features can improve oral bioavailability of insulin. CS-based hydrogels have been developed for the sustained release of drugs and the treatment of DM complications such as wound healing. Furthermore, CS-based nanoparticles can mediate delivery of phytochemicals and other therapeutic agents in DM therapy, and they are promising compounds for the treatment of DM complications, including nephropathy, neuropathy, and cardiovascular diseases, among others. The surface modification of nanostructures with CS can improve their properties in terms of drug delivery and release, biocompatibility, and others, causing high attention to these nanocarriers in DM therapy.

RETRACTED: Tangzhiqing-mediated NRF2 reduces autophagy-dependent ferroptosis to mitigate diabetes-related cognitive impairment neuronal damage

The publisher of Rejuvenation Research officially retracts the article entitled, "Tangzhiqing-mediated NRF2 reduces autophagy-dependent ferroptosis to mitigate diabetes-related cognitive impairment neuronal damage," by Lingyan Qiu, Mr. Kai Chen, Prof. Xu Wang, and Ms. Yun Zhao. (Rejuvenation Res 2023; epub 6 Jun; doi: 10.1089/rej.2023.0013). After the acceptance and Instant Online publication of the paper, the authors were contacted repeatedly regarding their page proofs, and for further clarification of unresolved issues within the paper. All attempts to reach the authors were unsuccessful. Concurrently, the publisher identified a problematic overlap with a paper published in 2023 in Endocrine, Metabolic & Immune Disorders - Drug Targets.1 This paper was subsequently withdrawn. These troubling details have led the editorial leadership of Rejuvenation Research to lose confidence in the validity of the submission and to retract the paper. All authors were notified of the decision to retract the paper via email. The lead author, Lingyan Qiu, and the corresponding author, Xu Wang, quickly responded and appealed the decision to retract. The appeal was denied. Reference 1. https://www.eurekaselect.com/article/132631. Withdrawn: Experimental study on NRF2 mediated by Chinese medicine tangzhiqing to reduce autophagy-dependent ferroptosis and alleviate neuron damage in HT22 mice with diabetes-related cognitive disorder. 22 June, 2023; DOI: 10.2174/1871530323666230622151649 Diabetes is a chronic condition defined by the body's inability to process glucose. The most common form, diabetes mellitus, reflects the body's insulin resistance, which leads to long-term raised glucose blood levels. These levels can cause oxidative damage, cell stress, and excessive autophagy throughout the body, including the nervous system. Diabetes-related cognitive impairment (DCI) results from chronic elevation of blood glucose, and as diabetes cases continue to rise, so too do comorbidities such as DCI. Although there are medications to address high blood glucose, there are few that can inhibit excessive autophagy and cell death. Therefore, we investigated if the Traditional Chinese Medicine, Tangzhiqing (TZQ), can reduce the impact of DCI in a high-glucose cell model. We used commercially available kits to evaluate cell viability, mitochondrial activity, and oxidative stress. We found that TZQ treatment increased cell viability, ensured continued mitochondrial activity, and reduced reactive oxygen species. We also found that TZQ functions by increasing NRF2 activity, which decreases the ferroptotic-associated pathways that involve p62, HO-1, and GPX4. Therefore, TZQ should be further investigated for its role in reducing DCI.

A Descriptive Review of the Action Mechanisms of Berberine, Quercetin and Silymarin on Insulin Resistance/Hyperinsulinemia and Cardiovascular Prevention

Insulin resistance (IR) and the associated hyperinsulinemia are early pathophysiological changes which, if not well treated, can lead to type 2 diabetes, endothelial dysfunction and cardiovascular disease. While diabetes care is fairly well standardized, the prevention and treatment of IR lacks a single pharmaceutical approach and many lifestyle and dietary interventions have been proposed, including a wide range of food supplements. Among the most interesting and well-known natural remedies, alkaloid berberine and the flavonol quercetin have particular relevance in the literature, while silymarin-the active principle of the Silybum marianum thistle-was traditionally used for lipid metabolism disorders and to sustain liver function. This review describes the major defects of insulin signaling leading to IR and the main properties of the three mentioned natural substances, their molecular targets and synergistic action mechanisms. The actions of berberine, quercetin and silymarin are partially superimposable as remedies against reactive oxygen intermediates generated by a high-lipid diet and by NADPH oxidase, which is triggered by phagocyte activation. Furthermore, these compounds inhibit the secretion of a battery of pro-inflammatory cytokines, modulate intestinal microbiota and are especially able to control the various disorders of the insulin receptor and post-receptor signaling systems. Although most of the evidence on the effects of berberine, quercetin and silymarin in modulating insulin resistance and preventing cardiovascular disease derive from experimental studies on animals, the amount of pre-clinical knowledge strongly suggests the need to investigate the therapeutic potential of these substances in human pathology.

Agomelatine's antiglycoxidative action-In vitro and in silico research and systematic literature review

Introduction

Agomelatine is an atypical antidepressant drug enhancing norepinephrine and dopamine liberation; nevertheless, additional mechanisms are considered for the drug's pharmacological action. Since protein glycoxidation plays a crucial role in depression pathogenesis, agomelatine's impact on carbonyl/oxidative stress was the research purpose.

Methods

Reactive oxygen species scavenging (hydroxyl radical, hydrogen peroxide, and nitrogen oxide) and antioxidant capacity (2,2-diphenyl-1-picrylhydrazyl radical and ferrous ion chelating assays) of agomelatine were marked. Agomelatine's antiglycoxidation properties were assayed in sugars (glucose, fructose, and galactose) and aldehydes- (glyoxal and methylglyoxal) glycated bovine serum albumin (BSA). Aminoguanidine and α-lipoic acid were used as standard glycation/oxidation inhibitors.

Results

Agomelatine did not show meaningful scavenging/antioxidant capacity vs. standards. Sugars/aldehydes increased glycation (↑kynurenine, ↑N-formylkynurenine, ↑dityrosine, ↑advanced glycation end products, and ↑β-amyloid) and oxidation (↑protein carbonyls and ↑advanced oxidation protein products) parameters in addition to BSA. Standards restored BSA baselines of glycation and oxidation markers, unlike agomelatine which sometimes even intensifies glycation above BSA + glycators levels. Molecular docking analysis of agomelatine in BSA demonstrated its very weak binding affinity.

Discussion

Agomelatine's very low affinity to the BSA could proclaim non-specific bonding and simplify attachment of glycation factors. Thereby, the drug may stimulate brain adaptation to carbonyl/oxidative stress as the systematic review indicates. Moreover, the drug's active metabolites could exert an antiglycoxidative effect.

Gymnema Sylvestre Supplementation Restores Normoglycemia, Corrects Dyslipidemia, and Transcriptionally Modulates Pancreatic and Hepatic Gene Expression in Alloxan-Induced Hyperglycemic Rats

Gymnema sylvestre is traditionally used as an herbal remedy for diabetes. The effect of Gymnema sylvestre supplementation on beta cell and hepatic activity was explored in an alloxan-induced hyperglycemic adult rat. Animals were made hyperglycemic via a single inj. (i.p) of Alloxan. Gymnema sylvestre was supplemented in diet @250 mg/kg and 500 mg/kg b.w. Animals were sacrificed, and blood and tissues (pancreas and liver) were collected for biochemical, expression, and histological analysis. Gymnema sylvestre significantly reduced blood glucose levels with a subsequent increase in plasma insulin levels in a dosage-dependent manner. Total oxidant status (TOS), malondialdehyde, LDL, VLDL, ALT, AST, triglyceride, total cholesterol, and total protein levels were reduced significantly. Significantly raised paraoxonase, arylesterase, albumin, and HDL levels were also observed in Gymnema sylvestre treated hyperglycemic rats. Increased mRNA expression of Ins-1, Ins-2, Gck, Pdx1, Mafa, and Pax6 was observed, while decreased expression of Cat, Sod1, Nrf2, and NF-kB was observed in the pancreas. However, increased mRNA expression of Gck, Irs1, SREBP1c, and Foxk1 and decreased expression of Irs2, ChREBP, Foxo1, and FoxA2 were observed in the liver. The current study indicates the potent effect of Gymnema sylvestre on the transcription modulation of the insulin gene in the alloxan-induced hyperglycemic rat model. Enhanced plasma insulin levels further help to improve hyperglycemia-induced dyslipidemia through transcriptional modulation of hepatocytes.

Efficacy of a Novel Pleiotropic MMP-Inhibitor, CMC2.24, in a Long-Term Diabetes Rat Model with Severe Hyperglycemia-Induced Oral Bone Loss

Purpose

CMC2.24, a novel 4-(phenylaminocarbonyl)-chemically-modified-curcumin, is a pleiotropic MMP-Inhibitor of various inflammatory/collagenolytic diseases including periodontitis. This compound has demonstrated efficacy in host modulation therapy along with improved resolution of inflammation in various study models. The objective of current study is to determine the efficacy of CMC2.24 in reducing the severity of diabetes, and its long-term role as an MMP-inhibitor, in a rat model.

Methods

Twenty-one adult male Sprague-Dawley rats were randomly distributed into three groups: Normal (N), Diabetic (D) and Diabetic+CMC2.24 (D+2.24). All three groups were orally administered vehicle: carboxymethylcellulose alone (N, D), or CMC2.24 (D+2.24; 30mg/kg/day). Blood was collected at 2-months and 4-months' time-point. At completion, gingival tissue and peritoneal washes were collected/analyzed, and jaws examined for alveolar bone loss by micro-CT. Additionally, sodium hypochlorite(NaClO)-activation of human-recombinant (rh) MMP-9 and its inhibition by treatment with 10μM CMC2.24, Doxycycline, and Curcumin were evaluated.

Results

CMC2.24 significantly reduced the levels of lower-molecular-weight active-MMP-9 in plasma. Similar trend of reduced active-MMP-9 was also observed in cell-free peritoneal and pooled gingival extracts. Thus, treatment substantially decreased conversion of pro- to actively destructive proteinase. Normalization of the pro-inflammatory cytokine (IL-1ß, resolvin-RvD1), and diabetes-induced osteoporosis was observed in presence of CMCM2.24. CMC2.24 also exhibited significant anti-oxidant activity by inhibiting the activation of MMP-9 to a lower-molecular-weight (82kDa) pathologically active form. All these systemic and local effects were observed in the absence of reduction in severity of hyperglycemia.

Conclusion

CMC2.24 reduced activation of pathologic active-MMP-9, normalized diabetic osteoporosis, and promoted resolution of inflammation but had no effect on the hyperglycemia in diabetic rats. This study also highlights the role of MMP-9 as an early/sensitive biomarker in the absence of change in any other biochemical parameter. CMC2.24 also inhibited significant activation of pro-MMP-9 by NaOCl (oxidant) adding to known mechanisms by which this compound treats collagenolytic/inflammatory diseases including periodontitis.

Early Detection Is the Best Prevention-Characterization of Oxidative Stress in Diabetes Mellitus and Its Consequences on the Cardiovascular System

Previous studies demonstrated an important role of oxidative stress in the pathogenesis of cardiovascular disease (CVD) in diabetic patients due to hyperglycemia. CVD remains the leading cause of premature death in the western world. Therefore, diabetes mellitus-associated oxidative stress and subsequent inflammation should be recognized at the earliest possible stage to start with the appropriate treatment before the onset of the cardiovascular sequelae such as arterial hypertension or coronary artery disease (CAD). The pathophysiology comprises increased reactive oxygen and nitrogen species (RONS) production by enzymatic and non-enzymatic sources, e.g., mitochondria, an uncoupled nitric oxide synthase, xanthine oxidase, and the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX). Considering that RONS originate from different cellular mechanisms in separate cellular compartments, adequate, sensitive, and compartment-specific methods for their quantification are crucial for early detection. In this review, we provide an overview of these methods with important information for early, appropriate, and effective treatment of these patients and their cardiovascular sequelae.

The impact of glucose on mitochondria and life span is determined by the integrity of proline catabolism in Caenorhabditis elegans

Mutations in genes involved in mitochondrial proline catabolism lead to the rare genetic disorder hyperprolinemia in humans. We have previously reported that mutations of proline catabolic genes in Caenorhabditis elegans impair mitochondrial homeostasis and shorten life span, and that these effects surprisingly occur in a diet type-dependent manner. Therefore, we speculated that a specific dietary component may mitigate the adverse effects of defective proline catabolism. Here, we discovered that high dietary glucose, which is generally detrimental to health, actually improves mitochondrial homeostasis and life span in C. elegans with faulty proline catabolism. Mechanistically, defective proline catabolism results in a shift of glucose catabolism toward the pentose phosphate pathway, which is crucial for cellular redox balance. This shift helps to maintain mitochondrial reactive oxygen species homeostasis and to extend life span, as suppression of the pentose phosphate pathway enzyme GSPD-1 prevents the favorable effects of high glucose. In addition, we demonstrate that this crosstalk between proline and glucose catabolism is mediated by the transcription factor DAF-16. Altogether, these findings suggest that a glucose-rich diet may be advantageous in certain situations and might represent a potentially viable treatment strategy for disorders involving impaired proline catabolism.

Association between serum complement 1q and the associated factors of acute ischemic stroke in patients with type 2 diabetes

OBJECTIVE

The aim of this study was to examine the association between serum complement 1q (C1q) and the associated factors of acute ischemic stroke in patients with type 2 diabetes (T2DM).

METHODS

The baseline clinical variables of the participants were collected, and the levels of blood lipids, blood sugar, inflammatory cytokines, and C1q in the three groups were then compared. The variables which affected the associated factors of acute ischemic stroke in T2DM cases were determined.

RESULTS

The levels of C1q in the DAIS group were increased significantly compared with those in the T2DM group. Receiver operating characteristic curve analyses showed that the AUC for C1q and the combined diagnosis of acute ischemic stroke were 0.830 (95%CI 0.747-0.914), with a sensitivity of 0.854 and specificity of 0.780. The results of Pearson's correlation analyses demonstrated that C1q was associated positively with low-density lipoprotein cholesterol (LDL-C), fasting blood glucose (PBG), 2-h postprandial blood glucose (2h PG), and high-sensitive C reaction protein (hs-CRP) (all p < .05). Stratified analysis showed that there was a positive relationship between C1q and the associated factors of acute ischemic stroke for partial LDL-C, and hs-CRP strata. Logistic model analysis suggested that C1q was an independent risk factor for acute ischemic stroke in patients with T2DM. After adjusting for potential confounders, a one-standard deviation (SD) increase in C1q level was strongly related to an approximately 1.5-fold increased risk of acute ischemic stroke in cases with a hs-CRP ≥1.78 mg/L.

CONCLUSION

In DAIS patients, the levels of C1q were increased significantly and were an independent associated factor which affected the occurrence of acute ischemic stroke.

Dietary Sugar Intake Associated with a Higher Risk of Dementia in Community-Dwelling Older Adults

BACKGROUND

We have limited evidence for the relationship of high sugar intake with dementia risk.

OBJECTIVE

To determine whether high sugar intake is associated with an increased risk of dementia in community-dwelling older adultsMethods:This study included 789 participants of the Rush Memory and Aging Project (community-based longitudinal cohort study of older adults free of known dementia at enrollment), with annual clinical assessments and complete nutrient data (obtained by validated food frequency questionnaire). Clinical diagnosis of dementia is based on the criteria of the joint working group of the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association. We used Cox proportional hazard models.

RESULTS

118 participants developed dementia during 7.3±3.8 years of follow-up. Those in the highest quintile of total sugar intake were twice as likely to develop dementia than those in the lowest quintile (Q5 versus Q1:HR=2.10 (95% CI: 1.05, 4.19) when adjusted for age, sex, education, APOEɛ4 allele, calories from sources other than sugar, physical activity, and diet score. Higher percent calories from sugar were positively associated with dementia risk (β=0.042, p = 0.0009). In exploratory analyses, the highest versus lowest quintile of fructose and sucrose in the diet had higher dementia risk by 2.8 (95% CI: 1.38, 5.67) and 1.93 (95% CI: 1.05, 3.54) times, respectively.

CONCLUSIONS

A higher intake of total sugar or total calories from sugar is associated with increased dementia risk in older adults. Among simple sugars, fructose (e.g., sweetened beverages, snacks, packaged desserts) and sucrose (table sugar in juices, desserts, candies, and commercial cereals) are associated with higher dementia risk.

The consumption of sea buckthorn (Hippophae rhamnoides L.) effectively alleviates type 2 diabetes symptoms in spontaneous diabetic rats

Sea buckthorn (Hippophae rhamnoides L.) is described by various beneficial effects as it contains several bioactive substances characterized by antioxidant effects. These effects are closely related to the reduction of oxidative stress that is involved in the development of the disease. One such diseases is Diabetes mellitus, the prevalence of which is growing and is associated primarily with diet, lack of exercise and/or genetics. This study intends to examine the effects of sea buckthorn and metformin on body weight, water and feed intake, glycaemia, insulinemia, sorbitol accumulation and cataract development in Zucker diabetic fatty rats, which represent an animal model of type 2 Diabetes mellitus, as well as to characterize the individual content of bioactive substances and the antioxidant activity of sea buckthorn. Particular concentrations were applied (500 and 1000 mg.kg-1 body weight of sea buckthorn, and combinations with 150 mg.kg-1 body weight of metformin) by gastric gavage. The total antioxidant capacity and bioactive compounds were determined by spectrophotometric analysis. The best results of the study showed suppression of hyperglycaemia, water intake, decreased sorbitol levels in the lens of the eyes after sea buckthorn treatment. Determination of bioactive compounds showed significantly higher values in dry berries when compared to fresh berries of sea buckthorn and high total antioxidant capacity. Our results represent an interest in sea buckthorn and its potential use in the treatment of Diabetes mellitus as well as other experimental studies.

Psychometric properties of the Chinese version of the sugar-sweetened beverages media literacy scale for undergraduates

Specific domains of the Sugar-Sweetened Media Literacy Scale (SSM-ML) have been shown to significantly assess sugar-sweetened beverage (SSB) calorie intake in the US population. This study aimed to describe the psychometric properties of the revised Chinese version of the SSB-ML (C-SSB-ML) and evaluate its validity and reliability. Results from 975 undergraduates at two of the largest universities in a province in southwest China showed that Cronbach's alphas for the overall scale, the three dimensions, and two-halves analysis were satisfactory (0.71-0.92). The criterion-related validity of the C-SSB-ML was positively associated with the e Health literacy scale (eHEALS). Confirmatory factor analysis showed that the three-factor model of the C-SSB-ML had adequate fit indices χ² (153) = 4349.93, p < 0.001; Comparative fit index (CFI), Tucker-Lewis index (TLI), Incremental fit index (IFI) >0.90; Standardized Root Mean Square Residual (SRMR) <0.07; and Root Mean Square Error of Approximation (RMSEA) <0.08. Our findings provide evidence for a valid and reliable tool that can be used to assess sugar-sweetened media literacy in Chinese undergraduates and will help organizations leverage media literacy in strategy formulation to ensure SSB intake is controlled as much as possible through effective efforts on all fronts.

Irisin/FNDC5 influences myogenic markers on skeletal muscle following high and moderate-intensity exercise training in STZ-diabetic rats

In the present study, we investigated the effects of high-intensity interval training (HIIT) versus moderate-intensity continuous training (MICT) on irisin and expression of myogenic markers (paired box 7 (Pax7), myogenic differentiation 1 (MyoD), myogenin) in skeletal muscle of diabetic rats. Eighty-four male Wistar rats (6 weeks of age) were randomly divided into seven groups (n = 12): basic control (Co Basic), 8 weeks control (Co 8w), diabetes mellitus (DM), HIIT, DM + HIIT, MICT, and DM + MICT groups. Diabetes was induced by intraperitoneal injection of streptozotocin (STZ). TheV ˙ o 2 max protocol was characterized by running on a rodent treadmill with moderate intensity (60-70%V ˙ o 2 max ), 60 min per session, 5 days/week, for 6 weeks. HIIT consisted of six 3-min runs at a high intensity (80-90%V ˙ o 2 max ) alternated with 2-min running at low intensity (50%V ˙ o 2 max ), 30 min per session, 5 days/week, for 6 weeks. Results showed that DM decreased myoblast markers compared to Co Basic and Co 8w groups. Fibronectin type III domain-containing protein 5 (FNDC5) mRNA decrease was correlated with myoblast markers (Pax7 r = 0.632, p = 0.027; MyoD r = 0.999, p = 0.001; myogenin r = 1.000, p = 0.001) in DM group. DM + MICT significantly increased gene expression of MyoD, myogenin, and FNDC5 compared to DM and DM + HIIT. The results also showed that the intensity and duration of exercise on the treadmill were effective in stimulating irisin and myogenic markers after DM.

Detection and Quantification of Nanoparticle-Induced Intracellular ROS in Live Cells by Laser Scanning Confocal Microscopy

All living organisms utilise reactive oxygen species (ROS) for essential cellular functions, the majority of which involve signal transduction pathways, such as enzyme regulation, cell growth and differentiation signalling, and inflammation mediation. Increased ROS in cancer cells can be caused by abnormalities in the tumor environment. However, using fluorescence microscopy to detect and quantify ROS changes in biological systems is difficult for several reasons: (1) lack of specificity of ROS-sensitive probes, (2) high turnover of ROS species, (3) rapid decrease in ROS fluorescence with time, and (4) detection and quantification techniques with insufficient sensitivity. Existing approaches to ROS measurement using confocal microscopy imaging focus solely on ROS detection rather than quantification. A novel fluorescence-based ROS detection and quantification technique has been developed for the purpose of resolving the limitations of existing methods. In general, ROS is detected by fluorescence using instrumentation such as flow cytometry and laser scanning confocal microscopy. However, these approaches confirm only the presence or absence of ROS; they are not quantitative, which is essential for therapeutic applications. In the newly developed technique, cerium-based ROS-generating nanoparticles have been used to elevate the ROS in HT-1080 fibrosarcoma cells. The elevated ROS levels are detected using an H2DCFDA fluorescence probe, which is used widely for this application, and captured as digital images using a 488 nm fluorescence channel. Quantification of the ROS is achieved using script in MATLAB software to convert the fluorescence intensities to numerical values. Thus, this technique nearly simultaneously integrates both detection and quantification of the ROS, which provides the statistical justification necessary to support therapeutic translation.

Metformin use is associated with a lower risk of rotator cuff disease in patients with type 2 diabetes mellitus

AIMS

- Metformin has been mentioned to be protective against inflammation, degeneration, and oxidative stress, conditions that are associated with rotator cuff disease. To access the association between metformin use and risk of rotator cuff disease in patients with type 2 diabetes mellitus (DM).

METHODS

- This was a retrospective cohort study utilizing Taiwan National Health Insurance Research Database between January 1, 2000, and December 31, 2012 to retrieved participants. Metformin and propensity score matched never metformin users were determined at baseline (between the date of onset of DM and the index date), and followed to December 31, 2013. Propensity scores were adopted to address measurable confounders (including demographic variables, Diabetes Complications Severity Index, and relevant comorbidities and co-medication). A multivariable Cox proportional hazards regression model was applied to estimate the adjusted hazard ratios (HRs) for the risk of the first diagnosis of rotator cuff disease on the full cohort and on the propensity score matched cohort.

RESULTS

- In the propensity score matched cohort, a total of 34,964 individuals (19,416 [55.5%] men), 17,482 individuals were taking metformin, 559 [3.2%] of whom developed rotator cuff disease. Incidence of rotator cuff disease was 4.51 per 10,000 person-months in the metformin users and 5.11 in the controls. Among metformin group, the aHR (95% CI) was 0.879 (0.784-0.984) after full adjustment. The potential beneficial effect on the risk of rotator cuff disease was consistently observed across all subgroups, including sex, age, concomitant other glucose lowering drugs, and level of Diabetes Complications Severity Index (all P for interaction > 0.050).

CONCLUSION

- Metformin use was associated with a lower risk of rotator cuff disease in patients with type 2 DM.

Effects of 1,3,7-tribromodibenzo-p-dioxin, a natural dioxin on chicken embryos: Comparison with effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin

Several naturally occurring dioxins, including 1,3,7-tribromodibenzo-p-dioxin (1,3,7-TriBDD), synthesized by red algae, have been detected in the marine environment. As 1,3,7-TriBDD is accumulated in mussels and fish, predators, such as marine birds, are exposed to this congener, similar to anthropogenic dioxins (including 2,3,7,8-tetrachlorodibenzo-p-dioxin TCDD). However, little is known about the impact of 1,3,7-TriBDD exposure on the bird health. To understand the effects of 1,3,7-TriBDD on birds, the phenotypic effects and hepatic transcriptome were investigated in chicken (Gallus gallus) embryos treated with 27 μM (2.9 ng/g egg) and 137 μM (14.4 ng/g egg) 1,3,7-TriBDD. The blood glucose levels in the 1,3,7-TriBDD-treated groups were lower than those in the control group. The transcriptome analysis of 6520 sequences in the 27 and 137 μM 1,3,7-TriBDD-treated groups identified 733 and 596 differentially expressed genes (DEGs). Cytochrome P450 1A4 and 1A5 were also identified as DEGs, suggesting that the aryl hydrocarbon receptor is activated by this congener. Pathway and network analyses with DEGs suggested that 1,3,7-TriBDD may induce carcinogenic effects and metabolic alterations. These results were similar to the effects on TCDD-treated embryos. Nevertheless, the overall transcriptome results suggested that compared with TCDD, 1,3,7-TriBDD has a unique impact on insulin- and peroxisome-signaling pathways in chicken embryos. Differences in altered transcriptome profiles between 1,3,7-TriBDD- and TCDD-treated embryos may lead to different phenotypic effects: less severe effects of 1,3,7-TriBDD and more fatal effects of TCDD. Collectively, these findings warrant the further assessment of the hazard and risk of 1,3,7-TriBDD on marine animals, considering increased exposure due to climate change.

Curcumin, Polydatin and Quercetin Synergistic Activity Protects from High-Glucose-Induced Inflammation and Oxidative Stress

Chronic hyperglycemia, the diagnostic biomarker of Type 2 Diabetes Mellitus (T2DM), is a condition that fosters oxidative stress and proinflammatory signals, both involved in the promotion of cellular senescence. Senescent cells acquire a proinflammatory secretory phenotype, called SASP, exacerbating and perpetuating the detrimental effects of hyperglycemia. Bioactive compounds can exert antioxidant and anti-inflammatory properties. However, the synergistic anti-inflammatory and antioxidant effects of the most extensively investigated natural compounds have not been confirmed yet in senescent cells and in hyperglycemic conditions. Here, we exposed young and replicative senescent HUVEC (yHUVEC and sHUVEC) to a high-glucose (HG) condition (45 mM) and treated them with Polydatin (POL), Curcumin (CUR) and Quercetin (QRC), alone or in combination (MIX), to mirror the anti-inflammatory component OxiDef^TM contained in the novel nutraceutical Glicefen^TM (Mivell, Italy). In both yHUVEC and sHUVEC, the MIX significantly decreased the expression levels of inflammatory markers, such as MCP-1, IL-1β and IL-8, and ROS production. Importantly, in sHUVEC, a synergistic effect of the MIX was observed, suggesting its senomorphic activity. Moreover, the MIX was able to reduce the expression level of RAGE, a receptor involved in the activation of proinflammatory signaling. Overall, our data suggest that the consumption of nutraceuticals containing different natural compounds could be an adjuvant supplement to counteract proinflammatory and pro-oxidative signals induced by both hyperglycemic and senescence conditions.

Ornipural® Mitigates Malathion-Induced Hepato-Renal Damage in Rats via Amelioration of Oxidative Stress Biomarkers, Restoration of Antioxidant Activity, and Attenuation of Inflammatory Response

The current study was instigated by investigating the ameliorative potential of Ornipural^® solution against the hepato-renal toxicity of malathion. A total number of 35 male Wistar albino rats were divided equally into five groups. Group 1 served as control and received normal saline intraperitoneally. Group 2, the sham group, were administered only corn oil (vehicle of malathion) orally. Group 3 was orally intoxicated by malathion in corn oil at a dose of 135 mg/kg BW via intra-gastric gavage. Group 4 received malathion orally concomitantly with Ornipural^® intraperitoneally. Group 5 was given Ornipural^® solution in saline via intraperitoneal injection at a dose of (1 mL/kg BW). Animals received the treatment regime for 30 days. Histopathological examination revealed the harmful effect of malathion on hepatic and renal tissue. The results showed that malathion induced a significant decrease in body weight and marked elevation in the activity of liver enzymes, LDH, and ACP. In contrast, the activity of AchE and Paraoxonase was markedly decreased. Moreover, there was a significant increase in the serum content of bilirubin, cholesterol, and kidney injury markers. A significant elevation in malondialdehyde, nitric oxide (nitrite), and 8-hydroxy-2-deoxyguanosine was observed, along with a substantial reduction in antioxidant activity. Furthermore, malathion increased tumor necrosis factor-alpha, the upregulation of IL-1B, BAX, and IFN-β genes, and the downregulation of Nrf2, Bcl2, and HO-1 genes. Concurrent administration of Ornipural^® with malathion attenuated the detrimental impact of malathion through ameliorating metabolic biomarkers, restoring antioxidant activity, reducing the inflammatory response, and improving pathologic microscopic alterations. It could be concluded that Ornipural^® solution demonstrates hepatorenal defensive impacts against malathion toxicity at biochemical, antioxidants, molecular, and cellular levels.

How exposure to chronic stress contributes to the development of type 2 diabetes: A complexity science approach

Chronic stress contributes to the onset of type 2 diabetes (T2D), yet the underlying etiological mechanisms are not fully understood. Responses to stress are influenced by earlier experiences, sex, emotions and cognition, and involve a complex network of neurotransmitters and hormones, that affect multiple biological systems. In addition, the systems activated by stress can be altered by behavioral, metabolic and environmental factors. The impact of stress on metabolic health can thus be considered an emergent process, involving different types of interactions between multiple variables, that are driven by non-linear dynamics at different spatiotemporal scales. To obtain a more comprehensive picture of the links between chronic stress and T2D, we followed a complexity science approach to build a causal loop diagram (CLD) connecting the various mediators and processes involved in stress responses relevant for T2D pathogenesis. This CLD could help develop novel computational models and formulate new hypotheses regarding disease etiology.

Carnosine improves cognitive impairment through promoting SIRT6 expression and inhibiting ER stress in a diabetic encephalopathy model

Diabetic encephalopathy is one of complications of diabetes mellitus. Carnosine is a dipeptide composed of β-alanine and L-histidine. Study has shown that carnosine could ameliorate cognitive impairment in animal model with diabetes mellitus. However, the mechanism remains unclear. An animal model of type 2 diabetes (db/db mice) was used in this study. The animals were treated with 0.9 % saline or carnosine (100 mg/kg) for 8 weeks. Morris water maze was tested after drug administration. Oxidative stress-related factors malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX), and pro-inflammatory factors inducible nitric oxide synthase (iNOS) were measured. Synapse-related protein postsynapticdensity 95 (PSD95) and brain-derived neurotrophic factor (BDNF) were detected by western blot. Besides, the expressions of sirtuin 6 (SIRT6), binding immunoglobulin protein (BIP), protein kinase R-like endoplasmic reticulum kinase (PERK), phospho-protein kinase R-like endoplasmic reticulum kinase (P-PERK), inositol-requiring enzyme-1α (IRE1α), phospho-inositol-requiring enzyme-1α (P-IRE1α), activating transcription factor 6 (ATF6), C/EBP-homologous protein (CHOP) in the hippocampus of the brain were detected. The results showed that treatment with carnosine ameliorated cognitive impairment in db/db mice. Carnosine reduced neuronal oxidative stress damage and iNOS expression in db/db mice. Meanwhile, carnosine relieved neurodegeneration in the hippocampus of db/db mice. Furthermore, carnosine promoted the expression of SIRT6 and reduced the expressions of endoplasmic reticulum (ER) related factors (BIP, P-PERK, P-IRE1α, ATF6, CHOP). In conclusion, these data suggested that the protective effect of carnosine against diabetic encephalopathy might be related to SIRT6/ER stress pathway.

Antioxidant effect of chamomile tea on the salivary glands of streptozotocin-induced diabetic rats

This study aimed to analyze oxidative stress and the activity of antioxidant enzymes in the salivary glands of streptozotocin (STZ)-induced diabetic rats with ad libitum consumption of chamomile tea in substitution of water for 21 days. Rats were divided in two control groups (untreated control and treated control) and two diabetic groups (untreated diabetic and treated diabetic). Superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) activities, total antioxidant status (TAS), and malondialdehyde (MDA) concentrations were determined. The chemical composition of the chamomile essential oil revealed 39 compounds, accounting for 93.5% of the total oils. The polyphenolic profile of the tea showed the presence of apigenin, luteolin, umbelliferone, and esculetin. SOD, GPx, CAT, and TAS levels were lower in the parotid (PA) diabetic glands, but treatment increased their concentration in both the submandibular (SM) and PA diabetic salivary glands. Increased MDA levels were observed in the PA diabetic glands, which were decreased by the consumption of chamomile tea with a reduction in hyperglycemia compared to that in untreated diabetic rats. However, the SM diabetic glands showed no difference in the MDA content. The consumption of chamomile tea prevented oxidative stress in the PA glands of diabetic rats, exhibiting hypoglycemic and antioxidant effects. Thus, chamomile tea could be a potential candidate for preventing oral complications in diabetes mellitus.

Salvia hispanica L. seeds extract alleviate encephalopathy in streptozotocin-induced diabetes in rats: Role of oxidative stress, neurotransmitters, DNA and histological indices

CONTEXT

Diabetes mellitus (DM) is a metabolic disorder and may lead to cognitive dysfunctions.

OBJECTIVE

The aim of this work is to evaluate the potency of Salvia hispanica L. seeds (S. hispanica L.) (chia seeds) petroleum ether extract in attenuating brain complications associated with streptozotocin (STZ) induced diabetes in rats.

MATERIALS AND METHODS

Phytochemical composition of the seeds extract, macro and micro elements, vitamins, protein, carbohydrate and caloric values were estimated. Diabetes was induced by a single intraperitoneal injection of STZ (60 mg/kg body weight (b.wt)). Glibenclamide as a reference drug was also evaluated. The biochemical evaluation was done by measuring levels of glucose, insulin, α amylase, glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA), dopamine (DA), serotonin (5-HD), noradrenaline (NE), acetylcholinesterase (AchE), tumor necrosis factor-α (TNF-α), DNA fragmentation pattern and the histopathological profile of the brain hippocampus region.

RESULTS

Gas chromatography/mass spectrometry (GC/MS) analysis revealed the presence of twenty-five fatty acid esters and twenty-two compounds. Column chromatography led to the isolation of nine compounds. Treatment with the seeds extract revealed improvement of the measured parameters with variable degrees.

CONCLUSION

Chia seeds extract succeeded to attenuate the neurodegeneration in diabetic rats. Thereafter, it could be potentially used as a new dietary supplement against diabetic encephalopathy.

The role of inflammation and neurodegeneration in diabetic macular edema

The pathogenesis of diabetic macular edema (DME) is complex. Persistently high blood glucose activates multiple cellular pathways and induces inflammation, oxidation stress, and vascular dysfunction. Retinal ganglion cells, macroglial and microglial cells, endothelial cells, pericytes, and retinal pigment epithelium cells are involved. Neurodegeneration, characterized by dysfunction or apoptotic loss of retinal neurons, occurs early and independently from the vascular alterations. Despite the increasing knowledge on the pathways involved in DME, only limited therapeutic strategies are available. Besides antiangiogenic drugs and intravitreal corticosteroids, alternative therapeutic options tackling inflammation, oxidative stress, and neurodegeneration have been considered, but none of them has been currently approved.

In Vivo Toxicity Evaluation of Sugar Adulterated Heterotrigona itama Honey Using Zebrafish Model

Honey is prone to be adulterated through mixing with sugars, cheap and low-quality honey, and other adulterants. Consumption of adulterated honey may cause several health issues such as weight gain, diabetes, and liver and kidney dysfunction. Therefore, studying the impact of consumption of adulterated honey on consumers is critical since there is a lack of study in this field. Hence, the aims of this paper were: (1) to determine the lethal concentration (LC₅₀) of adulterated honey using zebrafish embryo, (2) to elucidate toxicology of selected adulterated honey based on lethal dose (LD₅₀) using adult zebrafish, (3) to determine the effects of adulterated honey on histological changes of zebrafish, and (4) to screen the metabolites profile of adulterated honey by using zebrafish blood serum. The LC₅₀ of Heterotrigona itama honey (acacia honey) and its sugar adulterants (light corn sugar, cane sugar, inverted sugar, and palm sugar in the proportion of 1-3% (w/w) from the total volume) was determined by the toxicological assessment of honey samples on zebrafish embryos (different exposure concentrations in 24, 48, 72, and 96 h postfertilization (hpf)). Pure H. itama honey represents the LC₅₀ of 34.40 ± 1.84 (mg/mL) at 96 hpf, while the inverted sugar represents the lowest LC₅₀ (5.03 ± 0.92 mg/mL) among sugar adulterants. The highest concentration (3%) of sugar adulterants were used to study the toxicology of adulterated honey using adult zebrafish in terms of acute, prolong-acute, and sub-acute tests. The results of the LD₅₀ from the sub-acute toxicity test of pure H. itama honey was 2.33 ± 0.24 (mg/mL). The histological studies of internal organs showed a lesion in the liver, kidney, and spleen of adulterated treated-honey groups compared to the control group. Furthermore, the LC-MS/MS results revealed three endogenous metabolites in both the pure and adulterated honey treated groups, as follows: (1) S-Cysteinosuccinic acid, (2) 2,3-Diphosphoglyceric acid, and (3) Cysteinyl-Tyrosine. The results of this study demonstrated that adulterated honey caused mortality, which contributes to higher toxicity, and also suggested that the zebrafish toxicity test could be a standard method for assessing the potential toxicity of other hazardous food additives. The information gained from this research will permit an evaluation of the potential risk associated with the consumption of adulterated compared to pure honey.

Elevated Serum Levels of Ischemia Modified Albumin and Malondialdehyde are Related to Atherogenic Index of Plasma in a Cohort of Prediabetes

BACKGROUND

Prediabetes, defined as impaired glucose tolerance and/or impaired fasting glucose, is a risk factor for future type 2 diabetes, dyslipidemia, cardiovascular disease and all-cause mortality. High serum levels of ischemia modified albumin (IMA) and malondialdehyde (MDA) as oxidative stress markers were determined in diabetes, however, no studies have investigated these markers together in prediabetes. The aim of the present study was to investigate the circulating levels of both IMA and MDA in a cohort of prediabetic adults. The possible associations between both markers and the atherogenic index of plasma (AIP) were also evaluated.

METHODS

This study enrolled 100 adults with prediabetes and 50 healthy controls matched for age and sex. Anthropometric measurements, fasting and 2-hour post load glucose, glycosylated hemoglobin (A1c), lipids profile, fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), high sensitivity C-reactive protein (hs-CRP), AIP, IMA and MDA were assessed.

RESULTS

IMA, MDA, hs-CRP and AIP were significantly higher in adults with prediabetes than in healthy controls. Male gender, fasting and post load glucose, A1c, fasting insulin, TGs, HDL-C, hs- CRP, AIP and MDA were independent predictor variables of IMA, whereas male gender, WC, fasting and post load glucose, A1c, fasting insulin, TC, TGs, LDL-C, HDL-C, hs-CRP and AIP were independent predictor variables of MDA.

CONCLUSION

The elevation of IMA concomitantly with MDA reflecting the antioxidant status in prediabetes, and their associations with hs-CRP and AIP should reinforce the idea of screening and treatment of prediabetes.

GLUT4 translocation in C2C12 myoblasts and primary mouse hepatocytes by an antihyperglycemic flavone from Tillandsia usneoides

BACKGROUND

Type 2 Diabetes (T2D) is characterized by deregulation in carbohydrate and lipid metabolism, with a very high mortality rate. Glucose Transporter type 4 (GLUT4) plays a crucial role in T2D and represents a therapeutic target of interest. Tillandsia usneoides (T. usneoides) is a plant used as a remedy for diabetes. T. usneoides decreased blood glucose in different experimental models. However, the involvement of GLUT4 in this effect has not yet been explored.

PURPOSE

This study aimed to investigate whether any component in T. usneoides might participate in the effect on blood glucose through a bioassay-guided fractionation, testing its potential antihyperglycemic effect in mice, as well as its influence on GLUT4 translocation in C2C12 myoblasts and primary hepatocytes.

METHODS

The aqueous extract and the Ethyl Acetate fraction (TU-AcOEt) of T. usneoides were evaluated in a hypoglycemic activity bioassay and in the glucose tolerance test in CD-1 mice. TU-AcOEt was fractionated, obtaining five fractions that were studied in an additional glucose tolerance test. C1F3 was fractioned again, and its fractions (C2F9-12, C2F22-25, and C2F38-44) were examined by HPLC. The C2F38-44 fraction was analyzed by Mass Spectrometry (MS) and subjected to additional fractionation. The fraction C3F6-9 was explored by Nuclear Magnetic Resonance (NMR), resulting in 5,7,4´-trihydroxy-3,6,3´,5´-tetramethoxyflavone (Flav1). Subsequently, a viability test was performed to evaluate the cytotoxic effect of Flav1 and fractions C2F9-12, C2F22-25. C2F38-44, and C3F30-41 in C2C12 myoblasts and primary mouse hepatocytes. Confocal microscopy was also performed to assess the effect of Flav1 and fractions on GLUT4 translocation.

RESULTS

The TU-AcOEt fraction exhibited a hypoglycemic and antihyperglycemic effect in mice, and its fractionation resulted in five fractions, among which fraction C1F3 decreased blood glucose. MS and NMR analysis revealed the presence of Flav1. Finally, Flav1 significantly promoted the translocation of GLUT4 in C2C12 myoblasts and primary hepatocytes.

CONCLUSION

To date, Flav1 has not been reported to have activity in GLUT4; this study provides evidence that T. usneoides is a plant with the potential to develop novel therapeutic agents for the control of T2D.

Microvascular basis of cognitive impairment in type 1 diabetes

The complex computations of the brain require a constant supply of blood flow to meet its immense metabolic needs. Perturbations in blood supply, even in the smallest vascular networks, can have a profound effect on neuronal function and cognition. Type 1 diabetes is a prevalent and insidious metabolic disorder that progressively and heterogeneously disrupts vascular signalling and function in the brain. As a result, it is associated with an array of adverse vascular changes such as impaired regulation of vascular tone, pathological neovascularization and vasoregression, capillary plugging and blood brain barrier disruption. In this review, we highlight the link between microvascular dysfunction and cognitive impairment that is commonly associated with type 1 diabetes, with the aim of synthesizing current knowledge in this field.

Influence of glucose, insulin fluctuation, and glycosylated hemoglobin on the outcome of sarcopenia in patients with type 2 diabetes mellitus

AIMS

To explore the effects of glucose, insulin, and glycosylated hemoglobin (HbA1c) levels on the outcome of sarcopenia in patients with type 2 diabetes mellitus (T2DM).

METHODS

A total of 482 T2DM patients were enrolled in the follow-up study. The median follow-up time was 36 months. Muscle mass and HbA1c were measured in all participants. And glucose, C-peptide and insulin levels were measured at 0 min, 30 min, and 120 min after glucose load. We subsequently analyzed daily glucose fluctuations and islet function before and after readmission as well as the influence of their changes on sarcopenia outcome.

RESULTS

After glucose load, incident sarcopenia patients showed greater glucose fluctuations and worse islet function than did non-sarcopenia patients. As HbA1c and standard deviation of blood glucose (SDBG) increased, readmitted non-sarcopenia patients showed a significantly increased odds ratio of incident sarcopenia; however, only patients with higher quartiles were statistically significant. Increased ΔAUC-C-peptide reduced the risk of incident sarcopenia (P < 0.05).

CONCLUSIONS

Patients with incident sarcopenia have poor glucose regulation and insufficient insulin secretion. Furthermore, as HbA1c and SDBG increased, AUC-C-peptide and AUC-insulin decreased in readmitted non-sarcopenia patients, the risk of incident sarcopenia increased.

Protective mechanisms of Taiwanese green propolis toward high glucose-induced inflammation via NLRP3 inflammasome signaling pathway in human gingival fibroblasts

OBJECTIVE

To investigate protective effects of Taiwanese green propolis (TGP) against high glucose-induced inflammatory responses in human gingival fibroblasts (HGFs) through NLRP3 inflammasome signaling pathway.

BACKGROUND

NLRP3 inflammasome has been implicated in the progression of both diabetes mellitus and periodontitis, suggesting a common potential therapeutic target for these diseases. Propolis is renowned for various biological activities, particularly anti-inflammation and antioxidant, representing a promising therapy for many conditions. However, underlying mechanisms remain unclear.

METHODS

The cytotoxicity of TGP was evaluated by cell viability assay. The mRNA levels and protein expression or secretion of various inflammatory molecules and NLRP3 inflammasome-related molecules in high glucose-exposed HGFs with or without pretreatment of TGP (5 μg/ml) were determined by real-time PCR and western blot or specific kits, respectively. Intracellular and mitochondrial ROS measurements, NADPH oxidase activity determination, and subcellular fractions were performed to assess ROS generation. The transcriptional activity of NF-κB was measured by luciferase reporter kit. The signaling components were further differentiated using pharmacological inhibitors of ROS and small interfering RNAs of TLR2, TLR4, or NF-κB.

RESULTS

High glucose could induce IL-1β-driven inflammatory responses in HGFs via the activation of NLRP3 inflammasome regulated by TLR2/TLR4 coupled ROS in NF-κB-dependent manner. TGP had no adverse impact on the cell viability of HGFs at concentrations no greater than 10 μg/ml, and could exert inhibitory effects on high glucose-induced inflammatory responses via the interruption of NLRP3 inflammasome signaling pathway.

CONCLUSION

Taiwanese green propolis could elicit protective effects against IL-1β-driven inflammation in high glucose-exposed HGFs through TLR2/TLR4 combined ROS/NF-κB/NLRP3 inflammasome pathway.

Myocardial salvage by succinate dehydrogenase inhibition in ischemia-reperfusion injury depends on diabetes stage in rats

Inhibition of succinate dehydrogenase (SDH) by Dimethyl Malonate (DiMal) reduces cardiac ischemia-reperfusion (IR) injury. We investigated the cardioprotective effect of DiMal in a rat model during advancing type 2 diabetes. Zucker Diabetic Fatty rats and lean controls were investigated corresponding to prediabetes, onset and mature diabetes. Hearts were mounted in an isolated perfused model, and subjected to IR for investigation of infarct size (IS) and mitochondrial respiratory control ratio (RCR). DiMal was administered for 10 min before ischemia. Compared with age-matched non-diabetic rats, prediabetic rats had larger IS (49 ± 4% vs. 36 ± 2%, p = 0.007), rats with onset diabetes smaller IS (51 ± 3% vs. 62 ± 3%, p = 0.05) and rats with mature diabetes had larger IS (79 ± 3% vs. 69 ± 2%, p = 0.06). At the prediabetic stage DiMal did not alter IS. At onset of diabetes DiMal 0.6 mM increased IS in diabetic but not in non-diabetic control rats (72 ± 4% vs. 51 ± 3%, p = 0.003). At mature diabetes DiMal 0.1 and 0.6 mM reduced IS (68 ± 3% vs. 79 ± 3% and 64 ± 5% vs. 79 ± 3%, p  = 0.1 and p = 0.01), respectively. DiMal 0.1 mM alone reduced IS in age-matched non-diabetic animals (55 ± 3% vs. 69 ± 2% p = 0.01). RCR was reduced at mature diabetes but not modulated by DiMal. Modulation of SDH activity results in variable infarct size reduction depending on presence and the stage of diabetes. Modulation of SDH activity may be an unpredictable cardioprotective approach.

Pathology, Risk Factors, and Oxidative Damage Related to Type 2 Diabetes-Mediated Alzheimer's Disease and the Rescuing Effects of the Potent Antioxidant Anthocyanin

The pathology and neurodegeneration in type 2 diabetes- (T2D-) mediated Alzheimer's disease (AD) have been reported in several studies. Despite the lack of information regarding the basic underlying mechanisms involved in the development of T2D-mediated AD, some common features of the two conditions have been reported, such as brain atrophy, reduced cerebral glucose metabolism, and insulin resistance. T2D phenotypes such as glucose dyshomeostasis, insulin resistance, impaired insulin signaling, and systemic inflammatory cytokines have been shown to be involved in the progression of AD pathology by increasing amyloid-beta accumulation, tau hyperphosphorylation, and overall neuroinflammation. Similarly, oxidative stress, mitochondrial dysfunction, and the generation of advanced glycation end products (AGEs) and their receptor (RAGE) as a result of chronic hyperglycemia may serve as critical links between diabetes and AD. The natural dietary polyflavonoid anthocyanin enhances insulin sensitivity, attenuates insulin resistance at the level of the target tissues, inhibits free fatty acid oxidation, and abrogates the release of peripheral inflammatory cytokines in obese (prediabetic) individuals, which are responsible for insulin resistance, systemic hyperglycemia, systemic inflammation, brain metabolism dyshomeostasis, amyloid-beta accumulation, and neuroinflammatory responses. In this review, we have shown that obesity may induce T2D-mediated AD and assessed the recent therapeutic advances, especially the use of anthocyanin, against T2D-mediated AD pathology. Taken together, the findings of current studies may help elucidate a new approach for the prevention and treatment of T2D-mediated AD by using the polyflavonoid anthocyanin.

β-Glucans as a panacea for a healthy heart? Their roles in preventing and treating cardiovascular diseases

Cardiovascular diseases (CVDs) are the leading cause of death worldwide. Factors increasing the risks for CVD development are related to obesity, diabetes, high blood cholesterol, high blood pressure and lifestyle. CVD risk factors may be treated with appropriate drugs, but prolonged can use cause undesirable side-effects. Among the natural products used in complementary and alternative medicines, are the β-ᴅ-glucans; biopolymers found in foods (cereals, mushrooms), and can easily be produced by microbial fermentation. Independent of source, β-glucans of the mixed-linked types [(1 → 3)(1 → 6)-β-ᴅ-glucans - fungal, and (1 → 3)(1 → 4)-β-ᴅ-glucans - cereal] have widely been studied because of their biological activities, and have demonstrated cardiovascular protective effects. In this review, we discuss the roles of β-ᴅ-glucans in various pathophysiological conditions that lead to CVDs including obesity, dyslipidemia, hyperglycemia, oxidative stress, hypertension, atherosclerosis and stroke. The β-glucans from all of the sources cited demonstrated potential hypoglycemic, hypocholesterolemic and anti-obesogenicity activities, reduced hypertension and ameliorated the atherosclerosis condition. More recently, β-glucans are recognized as possessing prebiotic properties that modulate the gut microbiome and impact on the health benefits including cardiovascular. Overall, all the studies investigated unequivocally demonstrated the dietary benefits of consuming β-glucans regardless of source, thus constituting a promising panaceutical approach to reduce CVD risk factors.

The Hsp90 Inhibitor 17-DMAG Attenuates Hyperglycemia-Enhanced Hemorrhagic Transformation in Experimental Stroke

Introduction

Hemorrhagic transformation (HT) is one of the most common complications of ischemic stroke which is exacerbated by hyperglycemia. Oxidative stress, inflammatory response, and matrix metalloproteinases (MMPs) have been evidenced to play a vital role in the pathophysiology of HT. Our previous study has reported that 17-DMAG, an Hsp90 inhibitor, protects the brain against ischemic injury via inhibiting inflammation and reducing MMP-9 after ischemia. However, whether 17-DMAG would attenuate HT in hyperglycemic middle cerebral artery occlusion (MCAO) rats is still unknown.

Methods

Acute hyperglycemia was induced by an injection of 50% dextrose. Rats were pretreated with 17-DMAG before MCAO. Infarction volume, hemorrhagic volume neurological scores, expressions of inflammatory molecules and tight junction proteins, and activity of MMP-2 and MMP-9 were assessed 24 h after MCAO.

Results

17-DMAG was found to reduce HT, improve neurological function, and inhibit expressions of inflammatory molecules and the activation of MMPs at 24 h after MCAO.

Conclusion

These results implicated that Hsp90 could be a novel therapeutic target in HT following ischemic stroke.