Brain injury with diabetes mellitus: evidence, mechanisms and treatment implications

Jaranol alleviates cognitive impairment in db/db mice through the PI3K/AKT pathway

The widely used Radix Astragali (RA) has significant therapeutic effects on cognitive impairment (CI) caused by type 2 diabetes (T2DM). However, the effective active ingredients and the precise mechanism underly RA alleviation of T2DM-induced CI still require further study. In this study, we aim to elucidate whether and how jaranol, a key effective active ingredient in RA, influences CI in db/db mice. We used various online databases and Cytoscape to screen jaranol as the most active ingredient of RA in the treatment of T2DM-induced CI. The fear conditioning experiment, new object recognition (NOR) test, and Morris water maze (MWM) test were conducted to assess the improvement effect of jaranol on CI in diabetic mice. The protein-protein interaction (PPI) network, Cytoscape, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to identify key genes. The levels of AKT and caspase-3 were determined by Western blotting. The number of surviving hippocampal neurons was verified through Nissl staining. AutoDock was utilized for predicting potential binding sites between jaranol and key genes.As a result, jaranol attenuated CI in db/db mice probably through activation of PI3K-AKT signaling pathway by inhibiting cell apoptosis in hippocampus. Furthermore, A329 near the active site of AKT1 had hydrogen bond with jaranol. In conclusion, we suggest that jaranol may have therapeutic applications in T2DM-induced CI by targeting the PI3K-AKT signaling pathway directly via key sites. Our study provides alternative drugs and potential therapeutic targets for the prevention and treatment of T2DM-induced CI.

Reversion of metabolic dysfunction-associated steatohepatitis by skeletal muscle-directed FGF21 gene therapy

The highly prevalent metabolic dysfunction-associated steatohepatitis (MASH) is associated with liver steatosis, inflammation, and hepatocyte injury, which can lead to fibrosis and may progress to hepatocellular carcinoma and death. New treatment modalities such as gene therapy may be transformative for MASH patients. Here, we describe that one-time intramuscular administration of adeno-associated viral vectors of serotype 1 (AAV1) encoding native fibroblast growth factor 21 (FGF21), a key metabolic regulator, resulted in sustained increased circulating levels of the factor, which mediated long-term (>1 year) MASH and hepatic fibrosis reversion and halted development of liver tumors in obese male and female mouse models. AAV1-FGF21 treatment also counteracted obesity, adiposity, and insulin resistance, which are significant drivers of MASH. Scale-up to large animals successfully resulted in safe skeletal muscle biodistribution and biological activity in key metabolic tissues. Moreover, as a step toward the clinic, circulating FGF21 levels were characterized in obese, insulin-resistant and MASH patients. Overall, these results underscore the potential of the muscle-directed AAV1-FGF21 gene therapy to treat MASH and support its clinical translation.

In Vivo Glucose Transporter-2 Regulation of Dorsomedial Versus Ventrolateral VMN Astrocyte Metabolic Sensor and Glycogen Metabolic Enzyme Gene Expression in Female Rat

Astrocyte glycogenolysis shapes ventromedial hypothalamic nucleus (VMN) regulation of glucostasis in vivo. Glucose transporter-2 (GLUT2), a plasma membrane glucose sensor, controls hypothalamic primary astrocyte culture glycogen metabolism in vitro. In vivo gene silencing tools and single-cell laser-catapult-microdissection/multiplex qPCR techniques were used here to examine whether GLUT2 governs dorsomedial (VMNdm) and/or ventrolateral (VMNvl) VMN astrocyte metabolic sensor and glycogen metabolic enzyme gene profiles. GLUT2 gene knockdown diminished astrocyte GLUT2 mRNA in both VMN divisions. Hypoglycemia caused GLUT2 siRNA-reversible up-regulation of this gene profile in the VMNdm, but down-regulated VMNvl astrocyte GLUT2 transcription. GLUT2 augmented baseline VMNdm and VMNvl astrocyte glucokinase (GCK) gene expression, but increased (VMNdm) or reduced (VMNvl) GCK transcription during hypoglycemia. GLUT2 imposed opposite control, namely stimulation versus inhibition of VMNdm or VMNvl astrocyte 5'-AMP-activated protein kinase-alpha 1 and -alpha 2 gene expression, respectively. GLUT2 stimulated astrocyte glycogen synthase (GS) gene expression in each VMN division. GLUT2 inhibited transcription of the AMP-sensitive glycogen phosphorylase (GP) isoform GP-brain type (GPbb) in each site, yet diminished (VMNdm) or augmented (VMNvl) astrocyte GP-muscle type (GPmm) mRNA. GLUT2 enhanced VMNdm and VMNvl glycogen accumulation during euglycemia, and curbed hypoglycemia-associated VMNdm glycogen depletion. Results show that VMN astrocytes exhibit opposite, division-specific GLUT2 transcriptional responsiveness to hypoglycemia. Data document divergent GLUT2 control of GCK, AMPK catalytic subunit, and GPmm gene profiles in VMNdm versus VMNvl astrocytes. Ongoing studies seek to determine how differential GLUT2 regulation of glucose and energy sensor function and glycogenolysis in each VMN location may affect local neuron responses to hypoglycemia.

Dopamine-mediated autocrine inhibition of insulin secretion

The aim of the present research was to explore the mechanisms underlying the role of dopamine in the regulation of insulin secretion in beta cells. The effect of dopamine on insulin secretion was investigated on INS 832/13 cell line upon glucose and other secretagogues stimulation. Results show that dopamine significantly inhibits insulin secretion stimulated by both glucose and other secretagogues, while it has no effect on the basal secretion. This effect requires the presence of dopamine during incubation with the various secretagogues. Both electron microscopy and immunohistochemistry indicate that in beta cells the D2 dopamine receptor is localized within the insulin granules. Blocking dopamine entry into the insulin granules by inhibiting the VMAT2 transporter with tetrabenazine causes a significant increase in ROS production. Our results confirm that dopamine plays an important role in the regulation of insulin secretion by pancreatic beta cells through a regulated and precise compartmentalization mechanisms.

Cannabidiol modulates contextual fear memory consolidation in animals with experimentally induced type-1 diabetes mellitus

OBJECTIVES

In view of the neuroprotective characteristic of cannabidiol (CBD) and its beneficial action on aversive memory in non-diabetic animals, we aimed to investigate in animals with experimentally induced type-1 diabetes mellitus (T1DM) whether CBD treatment would be able to impair the contextual fear memory consolidation, its generalisation and whether the effect would be lasting. We also investigated the CBD effect on anxiety-like responses.

METHODS

After T1DM induction, animals received single or more prolonged treatment with CBD and were submitted to the contextual fear conditioning test. As expression of activity-regulated cytoskeletal-associated (Arc) protein is necessary for memory consolidation, we evaluated its expression in the dorsal hippocampus (DH). For evaluating anxiety-related responses, animals were submitted to the elevated plus maze test (EPMT), in which the time and number of entries in the open arms were used as anxiety index.

RESULTS

A single injection of CBD impaired the contextual fear memory consolidation and its generalisation, which was evaluated by exposing the animal in a neutral context. This single injection was able to reduce the elevated expression of Arc in the DH from these animals. Interestingly, more prolonged treatment with CBD also impaired the persistence of context-conditioned fear memory and induced an anxiolytic-like effect, as the treated group spent more time in the open arms of the EPMT.

CONCLUSION

CBD interferes with contextual fear memory and the dosage regimen of treatment seems to be important. Moreover, we cannot rule out the involvement of emotional aspects in these processes related to fear memory.

Effects of exogenous ghrelin treatment on oxidative stress, inflammation and histological parameters in a fat-fed streptozotocin rat model

In this study, the anti-inflammatory, antioxidative, and protective effects of ghrelin were investigated in a fat-fed streptozotocin (STZ) rat model and compared with metformin, diabetes and the healthy control groups. Histopathological evaluations were performed on H&E-stained pancreas and brain sections. Biochemical parameters were investigated by enzyme-linked immunosorbent assay. Blood glucose levels were significantly decreased with ghrelin or metformin treatments than the diabetes group. STZ administration increased brain, renal and pancreatic IL-1β, TNF-α and MDA while decreasing GPX, CAT, SOD, and NGF levels. Ghrelin increased renal GPX, CAT, NGF pancreatic GPX, SOD, CAT, NGF and brain SOD, NGF while it decreased renal, pancreatic and brain IL-1β, TNF-α and MDA levels. Ghrelin reduced neuronal loss and degeneration in the cerebral cortex and hippocampus and greatly ameliorated diabetes-related damage in pancreas. In conclusion, the data suggested that ghrelin is an effective candidate as a protectant for reducing the adverse effects of diabetes.

Molecular mechanism and therapeutic strategy of bile acids in Alzheimer's disease from the emerging perspective of the microbiota-gut-brain axis

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the accumulation of amyloid-β outside neurons and Tau protein inside neurons. Various pathological mechanisms are implicated in AD, including brain insulin resistance, neuroinflammation, and endocrinal dysregulation of adrenal corticosteroids. These factors collectively contribute to neuronal damage and destruction. Recently, bile acids (BAs), which are metabolites of cholesterol, have shown neuroprotective potential against AD by targeting the above pathological changes. BAs can enter the systematic circulation and cross the blood-brain barrier, subsequently exerting neuroprotective effects by targeting several endogenous receptors. Additionally, BAs interact with the microbiota-gut-brain (MGB) axis to improve immune and neuroendocrine function during AD episodes. Gut microbes impact BA signaling in the brain through their involvement in BA biotransformation. In this review, we summarize the role and molecular mechanisms of BAs in AD while considering the MGB axis and propose novel strategies for preventing the onset and progression of AD.

Association between stress hyperglycemia ratio and functional outcomes in patients with acute ischemic stroke

OBJECTIVE

This study aimed to evaluate the association between stress hyperglycemia ratio (SHR) and poor functional outcomes at 90 days in patients with acute ischemic stroke (AIS).

METHODS

This study retrospectively collected 1988 AIS patients admitted to two hospitals in the Shenzhen area between January 2022 and March 2023. A total of 1255 patients with Fasting Blood-glucose (FBG) and hemoglobin A1c (HbA1C) values at admission were included in this analysis. SHR, measured by FBG/HbA1C, was evaluated as both a tri-categorical variable (Tertile 1: ≤ 0.83; Tertile 2: 0.84 -0.95; Tertile 3: ≥ 0.96). The outcome was poor functional outcomes (modified Rankin Scale [mRS] score 2-6) at 90 days. We performed univariate analysis, multiple equation regression analysis, stratified analysis, and interactive analysis.

RESULTS

Compared with patients in the lowest tertile of SHR, the highest tertile group had significantly lower odds of achieving poor functional outcomes (adjusted odds ratio, OR = 2.84, 95% CI: 2.02-3.99, P < 0.0001) at 90 days after adjusting for potential covariates. Similar results were observed after further adjustment for white blood cell count, neutrophil count, lymphocyte count, fasting blood glucose, stroke type, intravenous thrombolytic therapy, baseline Glasgow score, and baseline NIHSS score.

CONCLUSION

SHR, as measured by the FBG/HbA1C, was associated with an increased odds of achieving poor functional outcomes in patients with AIS at 90 days.

Neuroprotective Effects of Sodium-Glucose Cotransporter-2 (SGLT2) Inhibitors (Gliflozins) on Diabetes-Induced Neurodegeneration and Neurotoxicity: A Graphical Review

Diabetes is a chronic endocrine disorder that negatively affects various body systems, including the nervous system. Diabetes can cause or exacerbate various neurological disorders, and diabetes-induced neurodegeneration can involve several mechanisms such as mitochondrial dysfunction, activation of oxidative stress, neuronal inflammation, and cell death. In recent years, the management of diabetes-induced neurodegeneration has relied on several types of drugs, including sodium-glucose cotransporter-2 (SGLT2) inhibitors, also called gliflozins. In addition to exerting powerful effects in reducing blood glucose, gliflozins have strong anti-neuro-inflammatory characteristics that function by inhibiting oxidative stress and cell death in the nervous system in diabetic subjects. This review presents the molecular pathways involved in diabetes-induced neurodegeneration and evaluates the clinical and laboratory studies investigating the neuroprotective effects of gliflozins against diabetes-induced neurodegeneration, with discussion about the contributing roles of diverse molecular pathways, such as mitochondrial dysfunction, oxidative stress, neuro-inflammation, and cell death. Several databases-including Web of Science, Scopus, PubMed, Google Scholar, and various publishers, such as Springer, Wiley, and Elsevier-were searched for keywords regarding the neuroprotective effects of gliflozins against diabetes-triggered neurodegenerative events. Additionally, anti-neuro-inflammatory, anti-oxidative stress, and anti-cell death keywords were applied to evaluate potential neuronal protection mechanisms of gliflozins in diabetes subjects. The search period considered valid peer-reviewed studies published from January 2000 to July 2023. The current body of literature suggests that gliflozins can exert neuroprotective effects against diabetes-induced neurodegenerative events and neuronal dysfunction, and these effects are mediated via activation of mitochondrial function and prevention of cell death processes, oxidative stress, and inflammation in neurons affected by diabetes. Gliflozins can confer neuroprotective properties in diabetes-triggered neurodegeneration, and these effects are mediated by inhibiting oxidative stress, inflammation, and cell death.

Association between Age at Diagnosis of Type 2 Diabetes and Subsequent Risk of Dementia and Its Major Subtypes

Background/Objectives: Type 2 diabetes mellitus (T2DM) is a major contributor to cognitive decline and dementia in older adults; however, the role of the age of onset of T2DM in younger patients remains uncertain. We explored the association between the risk of dementia and its subtypes in relation to the age at T2DM diagnosis. Methods: This population cohort study included a total of 612,201 newly diagnosed T2DM patients. The controls were randomly selected from the general population and matched at a 1:2 ratio based on the propensity score. The outcomes of interest were all-cause dementia, Alzheimer's disease (AD), and vascular dementia (VD). The association of T2DM with dementia was stratified by the age at diagnosis of T2DM. Results: The mean ages of the subjects in the T2DM and control groups were 55.7 ± 13.0 and 55.7 ± 13.0. The patients with T2DM diagnosed at <50 years had the highest excess risk for most outcomes relative to the controls, with a hazard ratio (HR) (95% CI) of 3.29 (3.11-3.49) for all-cause dementia, 4.08 (3.18-5.24) for AD, and 5.82 (3.84-8.81) for VD. All risks were attenuated progressively with each increasing decade at the diagnostic age, but remained significant; for T2DM diagnosed at ≥80 years, the HR (95% CI) was 1.38 (1.34-1.41) for all-cause dementia, 1.35 (1.31-1.40) for AD, and 1.98 (1.70-2.30) for VD. Conclusions: We need to stratify T2DM management according to the age of diagnosis. Physicians should closely monitor cognitive function in patients with T2DM, especially in younger individuals.

Associations of sugar intake, high-sugar dietary pattern, and the risk of dementia: a prospective cohort study of 210,832 participants

BACKGROUND

Limited evidence demonstrated the potential relationship between dietary sugar intake and dementia. This association demands further clarification in a large-scale population.

METHODS

A total of 210,832 participants from the UK Biobank cohort were included in this prospective cohort study. Absolute and relative sugar intake and high-sugar dietary scores were utilized to reflect dietary sugar intake. Absolute sugar intake was identified by the Oxford WebQ in the UK Biobank. Relative sugar intake was calculated by dividing the absolute sugar intake by total diet energy. High-sugar dietary pattern was identified using the method of reduced rank regression. Cox proportional hazards regression analyses and restricted cubic splines were performed to examine the longitudinal associations between dietary sugar intake and all-cause dementia and its main subtype, Alzheimer's disease. Explorative mediation analyses were conducted to explore underlying mechanisms.

RESULTS

Increased absolute sugar intake (g/day) was significantly associated with a higher risk of all-cause dementia (HR = 1.003, [95%CI: 1.002-1.004], p < 0.001) and Alzheimer's disease (1.002, [1.001-1.004], 0.005). Relative sugar intake (%g/kJ/day) also demonstrated significant associations with all-cause dementia (1.317, [1.173-1.480], p < 0.001) and Alzheimer's disease (1.249, [1.041-1.500], 0.017), while the high-sugar dietary score was only significantly associated with a higher risk of all-cause dementia (1.090, [1.045-1.136], p < 0.001). In addition, both sugar intake and high-sugar dietary score demonstrated significant non-linear relationships with all-cause dementia and Alzheimer's disease (all p values for non-linearity < 0.05).

CONCLUSIONS

Our study provided evidence that excessive sugar intake was associated with dementia. Controlling the excess consumption of dietary sugar may be of great public health implications for preventing dementia.

Protective effects of treadmill exercise on apoptotic neuronal damage and astrocyte activation in ovariectomized and/or diabetic rat prefrontal cortex: molecular and histological aspects

OBJECTIVE

Both estrogen deprivation and diabetes mellitus are known as risk factors for neuronal damage. Using an animal model of ovariectomized and/or streptozotocin (STZ)-induced diabetes mellitus, we examined expression of apoptosis-related proteins, neuronal damage, and astrocyte activation in prefrontal cortex of rats with/without treadmill exercise.

METHODS

Adult female Wistar rats were divided into control, ovariectomized (Ovx, bilateral ovariectomy), diabetic (Dia, STZ 60 mg/kg; i.p.), and ovariectomized diabetic (Ovx + Dia) groups. Next, animals in each group were randomly subdivided into non-exercise and exercise subgroups. Animals in the exercise groups underwent moderate treadmill running for 4 weeks (5 days/week). Thereafter, expression of Bax, Bcl-2, and caspase-3, as apoptosis-related proteins, number of neurons, and number of glial fibrillary acidic protein (GFAP)-positive cells in prefrontal cortex were measured using immunoblotting, cresyl violet staining, and immunohistochemistry, respectively.

RESULTS

In both Dia and Ovx + Dia groups, Bax and caspase-3 protein levels and number of GFAP-positive cells were higher than those in the control group, while Bcl-2 protein level and number of neurons compared were lower than the control group. Beneficial effects of exercise to prevent apoptosis-mediated neuronal damage and astrocyte activation were also observed in the Dia group.

CONCLUSION

Based on our results, physical exercise could be beneficial to attenuate diabetes-induced neuronal damage in the prefrontal cortex via inhibition of apoptosis.

Assessment of Cognitive Flexibility in Jordanian Diabetic Patients by Wisconsin Card Sorting and Trail Making Tests: Implications with Demographic, Anthropometric and Therapeutic Variables

Purpose

Cognitive flexibility is a mental ability that aids in smoothly alternating between them tasks in the brain. Diabetes Mellitus (DM) is a, common disorder that has been associated with impairments in cognitive functions. This research is a retrospective case-control study aimed at establishing a clear relationship between cognitive flexibility and diabetes among Jordanians, considering demographic, anthropometric, and therapeutic variables.

Patients and Methods

The Wisconsin Card Sorting Test (WCST)-64 item and the Trail Making Test (TMT) assessed cognitive flexibility in 268 people with diabetes and healthy control. Demographic, therapeutic data were collected. We also measured waist-to-hip ratio (WHR) and body mass index (BMI). As the variables were non-normally distributed, non-parametric statistical tests were used to examine differences (Kruskal-Wallis) and correlation (Spearman) between variables.

Results

The patient group did worse on the WCST In contrast to the control group, patients exhibited more significant delays for both Part A and Part B of the TMT (p<0.05). Males had higher WCST conceptual level responses than females. In addition, participants with professional jobs showed less delay in TMT Part A (p<0.05). Age was positively correlated with WCST's total errors and TMT's Parts A and B (p<0.05). BMI was negatively correlated with the WCST's conceptual level of responses and positively correlated with TMT's Part B (p<0.05). In addition, urea and albumin levels were positively correlated with TMT's Part A (p<0.05). Furthermore, creatinine was positively correlated with WCST's total errors and TMT's Part A (p<0.05).

Conclusion

Some measures of cognitive flexibility are associated with DM status in the studied sample of Jordanians and other variables (educational levels, occupation, lifestyle, average duration of illness, and age).

MiR-18a affects hypoxia induced glucose metabolism transition in HT22 hippocampal neuronal cell line through the Hif1a gene

Hypoxia can cause a variety of diseases, including ischemic stroke and neurodegenerative diseases. Within a certain range of partial pressure of oxygen, cells can respond to changes in oxygen. Changes in oxygen concentration beyond a threshold will cause damage or even necrosis of tissues and organs, especially for the central nervous system. Therefore, it is very important to find appropriate measures to alleviate damage. MiRNAs can participate in the regulation of hypoxic responses in various types of cells. MiRNAs are involved in regulating hypoxic responses in many types of tissues by activating the hypoxia-inducible factor (HIF) to affect angiogenesis, glycolysis and other biological processes. By analyzing differentially expressed miRNAs in hypoxia and hypoxia-related studies, as well as the HT22 neuronal cell line under hypoxic stress, we found that the expression of miR-18a was changed in these models. MiR-18a could regulate glucose metabolism in HT22 cells under hypoxic stress by directly regulating the 3'UTR of the Hif1a gene. As a small molecule, miRNAs are easy to be designed into small nucleic acid drugs, so this study can provide a theoretical basis for the research and treatment of nervous system diseases caused by hypoxia.

Insulin receptor at the blood-brain barrier: Transport and signaling

The blood-brain barrier (BBB) is a unique system of the brain microvasculature that limits the exchange between the blood and the brain. Brain microvascular endothelial cells form the BBB as part of the neurovascular unit and express insulin receptors. The insulin receptor at the BBB has been studied in two different functional aspects. These functions include (1) the supplying of blood insulin to the brain and (2) the modulation of BBB function via insulin signaling. The first function involves drug delivery to the brain, while the second function is related to the association between central nervous system diseases and type 2 diabetes through insulin resistance. This chapter summarizes recent progress in research on the function of insulin receptors at the BBB.

Diabetes and diabetic associative diseases: An overview of epigenetic regulations of TUG1

The epigenetic regulation of lncRNA TUG1 has garnered significant attention in the context of diabetes and its associated disorders. TUG1's multifaceted roles in gene expression modulation, and cellular differentiation, and it plays a major role in the growth of diabetes and the issues that are related to it due to pathological processes. In diabetes, aberrant epigenetic modifications can lead to dysregulation of TUG1 expression, contributing to disrupted insulin signaling, impaired glucose metabolism, and beta-cell dysfunction. Moreover, it has been reported that TUG1 contributes to the development of problems linked to diabetes, such as nephropathy, retinopathy, and cardiovascular complications, through epigenetically mediated mechanisms. Understanding the epigenetic regulations of TUG1 offers novel insights into the primary molecular mechanisms of diabetes and provides a possible path for healing interventions. Targeting epigenetic modifications associated with TUG1 holds promise for restoring proper gene expression patterns, ameliorating insulin sensitivity, and mitigating the inception and development of diabetic associative diseases. This review highlights the intricate epigenetic landscape that governs TUG1 expression in diabetes, encompassing DNA methylation and alterations in histone structure, as well as microRNA interactions.

Plant-Derived Bioactive Compounds: Exploring Neuroprotective, Metabolic, and Hepatoprotective Effects for Health Promotion and Disease Prevention

There is a growing trend among consumers to seek out natural foods and products with natural ingredients. This shift in consumer preferences had a direct impact on both food and pharmaceutical industries, leading to a focus of scientific research and commercial efforts to meet these new demands. The aim of this work is to review recent available scientific data on foods of interest, such as the artichoke, gooseberry, and polygonoideae plants, as well as olive oil and red raspberries. Interestingly, the urgency of solutions to the climate change emergency has brought new attention to by-products of grapevine bunch stem and cane, which have been found to contain bioactive compounds with potential health benefits. There is a pressing need for a faster process of translating scientific knowledge from the laboratory to real-world applications, especially in the face of the increasing societal burden associated with non-communicable diseases (NCDs), environmental crises, the post-pandemic world, and ongoing violent conflicts around the world.

A mechanism linking ferroptosis and ferritinophagy in melatonin-related improvement of diabetic brain injury

Ferroptosis and ferritinophagy play critical roles in various disease contexts. Herein, we observed that ferroptosis and ferritinophagy were induced both in the brains of mice with diabetes mellitus (DM) and neuronal cells after high glucose (HG) treatment, as evidenced by decreases in GPX4, SLC7A11, and ferritin levels, but increases in NCOA4 levels. Interestingly, melatonin administration ameliorated neuronal damage by inhibiting ferroptosis and ferritinophagy both in vivo and in vitro. At the molecular level, we found that not only the ferroptosis inducer p53 but also the ferritinophagy mediator NCOA4 was the potential target of miR-214-3p, which was downregulated by DM status or HG insult, but was increased after melatonin treatment. However, the inhibitory effects of melatonin on ferroptosis and ferritinophagy were blocked by miR-214-3p downregulation. These findings suggest that melatonin is a potential drug for improving diabetic brain damage by inhibiting p53-mediated ferroptosis and NCOA4-mediated ferritinophagy through regulating miR-214-3p in neurons.

Development and validation of a prediction model for self-reported hypoglycemia risk in patients with type 2 diabetes: A longitudinal cohort study

AIMS/INTRODUCTION

To develop and validate a simple prediction model for hypoglycemia risk in patients with type 2 diabetes.

MATERIALS AND METHODS

We prospectively analyzed the data of 1,303 subjects in a third-class hospital in Tianjin and followed up their hypoglycemia events at 3 and 6 months. The hypoglycemia risk prediction models for 3 and 6 months were developed and the model performance was evaluated.

RESULTS

A total of 340 (28.4%) patients experienced hypoglycemia within 3 months and 462 (37.2%) within 6 months during the follow-up period. Age, central obesity, intensive insulin therapy, frequency of hypoglycemia in the past year, and hypoglycemia prevention education entered both model3month and model6month. The area under the receiver operating characteristic curve of model3month and model6month were 0.711 and 0.723, respectively. The Youden index was 0.315 and 0.361, while the sensitivities were 0.615 and 0.714, and the specificities were 0.717 and 0.631. The calibration curves showed that the models were similar to reality. The decision curves implied that the clinical net benefit of the model was clear.

CONCLUSIONS

The study developed 3 and 6 month hypoglycemia risk prediction models for patients with type 2 diabetes. The discrimination and calibration of the two prediction models were good, and might help to improve clinical decision-making and guide patients to more reasonable self-care and hypoglycemia prevention at home.

Modulation of gut microbiota with probiotics as a strategy to counteract endogenous and exogenous neurotoxicity

The existing data demonstrate that probiotic supplementation affords protective effects against neurotoxicity of exogenous (e.g., metals, ethanol, propionic acid, aflatoxin B1, organic pollutants) and endogenous (e.g., LPS, glucose, Aβ, phospho-tau, α-synuclein) agents. Although the protective mechanisms of probiotic treatments differ between various neurotoxic agents, several key mechanisms at both the intestinal and brain levels seem inherent to all of them. Specifically, probiotic-induced improvement in gut microbiota diversity and taxonomic characteristics results in modulation of gut-derived metabolite production with increased secretion of SFCA. Moreover, modulation of gut microbiota results in inhibition of intestinal absorption of neurotoxic agents and their deposition in brain. Probiotics also maintain gut wall integrity and inhibit intestinal inflammation, thus reducing systemic levels of LPS. Centrally, probiotics ameliorate neurotoxin-induced neuroinflammation by decreasing LPS-induced TLR4/MyD88/NF-κB signaling and prevention of microglia activation. Neuroprotective mechanisms of probiotics also include inhibition of apoptosis and oxidative stress, at least partially by up-regulation of SIRT1 signaling. Moreover, probiotics reduce inhibitory effect of neurotoxic agents on BDNF expression, on neurogenesis, and on synaptic function. They can also reverse altered neurotransmitter metabolism and exert an antiamyloidogenic effect. The latter may be due to up-regulation of ADAM10 activity and down-regulation of presenilin 1 expression. Therefore, in view of the multiple mechanisms invoked for the neuroprotective effect of probiotics, as well as their high tolerance and safety, the use of probiotics should be considered as a therapeutic strategy for ameliorating adverse brain effects of various endogenous and exogenous agents.

The dangerous "West Coast Swing" by hyperglycaemia and chronic stress in the mouse hippocampus: Role of kynurenine catabolism

Growing epidemiological studies highlight a bi-directional relationship between depressive symptoms and diabetes mellitus. However, the detrimental impact of their co-existence on mental health suggests the need to treat this comorbidity as a separate entity rather than the two different pathologies. Herein, we characterized the peculiar mechanisms activated in mouse hippocampus from the concurrent development of hyperglycaemia, characterizing the different diabetes subtypes, and chronic stress, recognized as a possible factor predisposing to major depression. Our work demonstrates that kynurenine overproduction, leading to apoptosis in the hippocampus, is triggered in a different way depending on hyperglycaemia or chronic stress. Indeed, in the former, kynurenine appears produced by infiltered macrophages whereas, in the latter, peripheral kynurenine preferentially promotes resident microglia activation. In this scenario, QA, derived from kynurenine catabolism, appears a key mediator causing glutamatergic synapse dysfunction and apoptosis, thus contributing to brain atrophy. We demonstrated that the coexistence of hyperglycaemia and chronic stress worsened hippocampal damage through alternative mechanisms, such as GLUT-4 and BDNF down-expression, denoting mitochondrial dysfunction and apoptosis on one hand and evoking the compromission of neurogenesis on the other. Overall, in the degeneration of neurovascular unit, hyperglycaemia and chronic stress interacted each other as the partners of a "West Coast Swing" in which the leading role can be assumed alternatively by each partner of the dance. The comprehension of these mechanisms can open novel perspectives in the management of diabetic/depressed patients, but also in the understanding the pathogenesis of other neurodegenerative disease characterized by the compromission of hippocampal function.

White matter brain age as a biomarker of cerebrovascular burden in the ageing brain

As the brain ages, it almost invariably accumulates vascular pathology, which differentially affects the cerebral white matter. A rich body of research has investigated the link between vascular risk factors and the brain. One of the less studied questions is that among various modifiable vascular risk factors, which is the most debilitating one for white matter health? A white matter specific brain age was developed to evaluate the overall white matter health from diffusion weighted imaging, using a three-dimensional convolutional neural network deep learning model in both cross-sectional UK biobank participants (n = 37,327) and a longitudinal subset (n = 1409). White matter brain age gap (WMBAG) was the difference between the white matter age and the chronological age. Participants with one, two, and three or more vascular risk factors, compared to those without any, showed an elevated WMBAG of 0.54, 1.23, and 1.94 years, respectively. Diabetes was most strongly associated with an increased WMBAG (1.39 years, p < 0.001) among all risk factors followed by hypertension (0.87 years, p < 0.001) and smoking (0.69 years, p < 0.001). Baseline WMBAG was associated significantly with processing speed, executive and global cognition. Significant associations of diabetes and hypertension with poor processing speed and executive function were found to be mediated through the WMBAG. White matter specific brain age can be successfully targeted for the examination of the most relevant risk factors and cognition, and for tracking an individual's cerebrovascular ageing process. It also provides clinical basis for the better management of specific risk factors.

Banxia Xiexin Decoction Prevents HT22 Cells from High Glucose-induced Neurotoxicity via JNK/SIRT1/Foxo3a Signaling Pathway

BACKGROUND

Type 2 diabetes-associated cognitive dysfunction (DCD) is a chronic complication of diabetes that has gained international attention. The medicinal compound Banxia Xiexin Decoction (BXXXD) from traditional Chinese medicine (TCM) has shown potential in improving insulin resistance, regulating endoplasmic reticulum stress (ERS), and inhibiting cell apoptosis through various pathways. However, the specific mechanism of action and medical value of BXXXD remain unclear.

METHODS

We utilized TCMSP databases to screen the chemical constituents of BXXXD and identified DCD disease targets through relevant databases. By using Stitch and String databases, we imported the data into Cytoscape 3.8.0 software to construct a protein-protein interaction (PPI) network and subsequently identified core targets through network topology analysis. The core targets were subjected to Gene Ontology (GO) functional enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. The results were further validated through in vitro experiments.

RESULTS

Network pharmacology analysis revealed the screening of 1490 DCD-related targets and 190 agents present in BXXXD. The topological analysis and enrichment analysis conducted using Cytoscape software identified 34 core targets. Additionally, GO and KEGG pathway analyses yielded 104 biological targets and 97 pathways, respectively. BXXXD exhibited its potential in treating DCD by controlling synaptic plasticity and conduction, suppressing apoptosis, reducing inflammation, and acting as an antioxidant. In a high glucose (HG) environment, the expression of JNK, Foxo3a, SIRT1, ATG7, Lamp2, and LC3 was downregulated. BXXXD intervention on HT22 cells potentially involved inhibiting excessive oxidative stress, promoting neuronal autophagy, and increasing the expression levels of JNK, SIRT1, Foxo3a, ATG7, Lamp2, and LC3. Furthermore, the neuroprotective effect of BXXXD was partially blocked by SP600125, while quercetin enhanced the favorable role of BXXXD in the HG environment.

CONCLUSION

BXXXD exerts its effects on DCD through multiple components, targets, levels, and pathways. It modulates the JNK/SIRT1/Foxo3a signaling pathway to mitigate autophagy inhibition and apoptotic damage in HT22 cells induced by HG. These findings provide valuable perspectives and concepts for future clinical trials and fundamental research.

The relationship between diabetic ketoacidosis and suicidal or self-injurious behaviour: A systematic review

Background

It has been suggested that there may be an association between type 1 diabetes (T1DM) and suicide, with one study reporting a rate 11 times that of the general population The aim of this paper was to investigate the association between Diabetic ketoacidosis (DKA: a life-threatening acute complication of T1DM) and suicidal behaviours in people with T1DM.

Methods

We performed a search of the following databases: PubMed, PsychInfo, and Embase for papers which explored the association between suicidal behaviours and self-harm with DKA in T1DM. We excluded case reports and review papers.

Results

Only three papers explored the relationship between DKA and self-harm. One study found an association between DKA and self-harm in a national cohort of people with type 1 diabetes and schizophrenia. The second found a significant increase in psychiatric admissions for self-harm following an episode of DKA. The third study reported that patients with diabetes and a history of self-harm were at elevated risk of a range of diabetes complications including DKA. These findings indicate an association between DKA and self-harm and support the guidelines in recommending a psychosocial assessment where DKA cannot be explained.

Conclusions

This review suggests that DKA is associated with suicidal or self-injurious behaviours. The small number of studies and the seriousness of this issue highlight the importance of further research on this topic, to improve the evidence base for the identification and treatment of risk of suicidal behaviours in people with T1DM.

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.

Central nervous system microstructural alterations in Type 1 diabetes mellitus: A systematic review of diffusion Tensor imaging studies

AIMS

Type 1 diabetes mellitus (T1DM) is a chronic childhood disease with potentially persistent CNS disruptions. In this study, we aimed to systematically review diffusion tensor imaging studies in patients with T1DM to understand the microstructural effects of this entity on individuals' brains METHODS: We performed a systematic search and reviewed the studies to include the DTI studies in individuals with T1DM. The data for the relevant studies were extracted and a qualitative synthesis was performed.

RESULTS

A total of 19 studies were included, most of which showed reduced FA widespread in optic radiation, corona radiate, and corpus callosum, as well as other frontal, parietal, and temporal regions in the adult population, while most of the studies in the juvenile patients showed non-significant differences or a non-persistent pattern of changes. Also, reduced AD and MD in individuals with T1DM compared to controls and non-significant differences in RD were noted in the majority of studies. Microstructural alterations were associated with clinical profile, including age, hyperglycemia, diabetic ketoacidosis and cognitive performance.

CONCLUSION

T1DM is associated with microstructural brain alterations including reduced FA, MD, and AD in widespread brain regions, especially in association with glycemic fluctuations and in adult age.

Case report: Fatal insulin overdose in a dog with type 1 diabetes mellitus-characteristics and successful management

Administering more than 10 times the therapeutic dose of insulin is extremely rare in diabetic dogs and is life threatening with hypoglycemia and seizures if not accompanied by appropriate treatment. A 15-year-old, castrated male miniature poodle dog managed for diabetes presented with depression, disorientation, ataxia, and cluster seizures. The dog had been administered 11.1 U/kg of neutral protamine hegadorn (NPH) insulin (10 times the prescribed dose) 3 h before the onset of symptoms. Blood analysis revealed hypoglycemia, with a circulating glucose level of <50 mg/dL. To treat the hypoglycemia-induced seizures, dextrose was repeatedly administered intravenously. Repeated generalized seizures were treated with anticonvulsants and intermittent mannitol. Since refractory hypoglycemia persisted 24 h after the insulin overdose, it was decided to proceed with glucagon treatment (15-30 ng/kg/min titrated to the blood glucose level after a loading dose of 50 ng/kg intravenous bolus infusion). After 37 h of glucagon treatment, blood glucose levels stabilized. After entering a hyperglycemic state, NPH insulin was administered to manage insulin-dependent diabetes mellitus. This is the first case documented of successful treatment with glucagon, anticonvulsants and intermittent mannitol for refractory hypoglycemia and seizure caused by fatal insulin overdose. Thus, it has great clinical value in veterinary medicine.

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.

Nicotinamide Prevents Diabetic Brain Inflammation via NAD+-Dependent Deacetylation Mechanisms

This study investigated the effect of nicotinamide (NAM) supplementation on the development of brain inflammation and microglial activation in a mouse model of type 1 diabetes mellitus. C57BL/6J male mice, which were made diabetic with five consecutive, low-dose (55 mg/kg i.p.) streptozotocin (STZ) injections. Diabetic mice were randomly distributed in different experimental groups and challenged to different doses of NAM (untreated, NAM low-dose, LD, 0.1%; NAM high-dose, HD, 0.25%) for 25 days. A control, non-diabetic group of mice was used as a reference. The NAD+ content was increased in the brains of NAM-treated mice compared with untreated diabetic mice (NAM LD: 3-fold; NAM HD: 3-fold, p-value < 0.05). Immunohistochemical staining revealed that markers of inflammation (TNFα: NAM LD: -35%; NAM HD: -46%; p-value < 0.05) and microglial activation (IBA-1: NAM LD: -29%; NAM HD: -50%; p-value < 0.05; BDKRB1: NAM LD: -36%; NAM HD: -37%; p-value < 0.05) in brains from NAM-treated diabetic mice were significantly decreased compared with non-treated T1D mice. This finding was accompanied by a concomitant alleviation of nuclear NFκB (p65) signaling in treated diabetic mice (NFκB (p65): NAM LD: -38%; NAM HD: -53%, p-value < 0.05). Notably, the acetylated form of the nuclear NFκB (p65) was significantly decreased in the brains of NAM-treated, diabetic mice (NAM LD: -48%; NAM HD: -63%, p-value < 0.05) and inversely correlated with NAD+ content (r = -0.50, p-value = 0.03), suggesting increased activity of NAD+-dependent deacetylases in the brains of treated mice. Thus, dietary NAM supplementation in diabetic T1D mice prevented brain inflammation via NAD+-dependent deacetylation mechanisms, suggesting an increased action of sirtuin signaling.

Amygdala activity and amygdala-hippocampus connectivity: Metabolic diseases, dementia, and neuropsychiatric issues

With rapid aging of the population worldwide, the number of people with dementia is dramatically increasing. Some studies have emphasized that metabolic syndrome, which includes obesity and diabetes, leads to increased risks of dementia and cognitive decline. Factors such as insulin resistance, hyperglycemia, high blood pressure, dyslipidemia, and central obesity in metabolic syndrome are associated with synaptic failure, neuroinflammation, and imbalanced neurotransmitter levels, leading to the progression of dementia. Due to the positive correlation between diabetes and dementia, some studies have called it "type 3 diabetes". Recently, the number of patients with cognitive decline due to metabolic imbalances has considerably increased. In addition, recent studies have reported that neuropsychiatric issues such as anxiety, depressive behavior, and impaired attention are common factors in patients with metabolic disease and those with dementia. In the central nervous system (CNS), the amygdala is a central region that regulates emotional memory, mood disorders, anxiety, attention, and cognitive function. The connectivity of the amygdala with other brain regions, such as the hippocampus, and the activity of the amygdala contribute to diverse neuropathological and neuropsychiatric issues. Thus, this review summarizes the significant consequences of the critical roles of amygdala connectivity in both metabolic syndromes and dementia. Further studies on amygdala function in metabolic imbalance-related dementia are needed to treat neuropsychiatric problems in patients with this type of dementia.

Diabetic vascular diseases: molecular mechanisms and therapeutic strategies

Vascular complications of diabetes pose a severe threat to human health. Prevention and treatment protocols based on a single vascular complication are no longer suitable for the long-term management of patients with diabetes. Diabetic panvascular disease (DPD) is a clinical syndrome in which vessels of various sizes, including macrovessels and microvessels in the cardiac, cerebral, renal, ophthalmic, and peripheral systems of patients with diabetes, develop atherosclerosis as a common pathology. Pathological manifestations of DPDs usually manifest macrovascular atherosclerosis, as well as microvascular endothelial function impairment, basement membrane thickening, and microthrombosis. Cardiac, cerebral, and peripheral microangiopathy coexist with microangiopathy, while renal and retinal are predominantly microangiopathic. The following associations exist between DPDs: numerous similar molecular mechanisms, and risk-predictive relationships between diseases. Aggressive glycemic control combined with early comprehensive vascular intervention is the key to prevention and treatment. In addition to the widely recommended metformin, glucagon-like peptide-1 agonist, and sodium-glucose cotransporter-2 inhibitors, for the latest molecular mechanisms, aldose reductase inhibitors, peroxisome proliferator-activated receptor-γ agonizts, glucokinases agonizts, mitochondrial energy modulators, etc. are under active development. DPDs are proposed for patients to obtain more systematic clinical care requires a comprehensive diabetes care center focusing on panvascular diseases. This would leverage the advantages of a cross-disciplinary approach to achieve better integration of the pathogenesis and therapeutic evidence. Such a strategy would confer more clinical benefits to patients and promote the comprehensive development of DPD as a discipline.

Evaluación del desempeño cognitivo en escolares y adolescentes con diabetes mellitus tipo 1

The study aimedto evaluate the cognitive functioning of children and adolescents with type 1 diabetes mellitus (T1DM) recruited from the IAHULA Endocrinology Outpatient Unit and to compare it to that of non-diabetics as to investigate the influence on cognition of factors re-lated to the disease. An analytical, cross-sectional observational study was carried out on a group of 30 patients with T1DM between 8 and 16 years of age and on a control group of 30 individuals matched by age, gender, education, and socioeconomic status. Interrogation and review of medi-cal records to obtain data on the clinical characteristics and treatment of T1DM were conducted. The WISC IV test was then applied to evaluate cognition and intellectual coefficient (IQ). The average age of the diabetic patients was 13.27±2.31 years, and half of them were male. Lower scores were found in the different domains of the WISC IV in the group with T1DM (p<0.01). The IQ was found to be lower in children with T1DM than in con-trols (75.47±13.87 vs. 88.57±11.06; p=0.0001). Likewise, a higher fre-quency of IQ scores below the 10th percentile was observed in the diabetic children (63.3% vs. 33.3%; p=0.02; Odds ratio: 3.45; 95%CI: 1.19-9.99). It was concluded that T1DM negatively impacts the cognitive performance of children and adolescents. Cognitive evaluation of these patients is recom-mended, as it could affect their daily life.

Neuromodulatory effect of the combination of metformin and vitamin D3 triggered by purinergic signaling in type 1 diabetes induced-rats

Several studies have indicated the vitamin D deficiency in the development of macro- and microvascular complications of diabetes mellitus (DM) including DM-related cognitive dysfunction. The purinergic system plays an important role in the modulation of a variety of mechanisms, including neuroinflammation, plasticity, and cell-cell communication. In addition, purines, their receptors, and enzymes can regulate the purinergic axis at different levels in type 1 DM (T1DM). This study evaluated the effects of vitamin D₃ alone or in combination with metformin in the behavioral performance of streptozotocin-induced T1DM rats. The effects of this combination on the metabolism of ATP and ADP were also studied by NTPDase (CD39), AMP by 5'-nucleotidase (CD73), and adenosine by adenosine deaminase (E-ADA) in the brain and peripheral lymphocytes of type 1 diabetic STZ-induced rats. The results showed that anxiety and memory loss from the DM condition reverted after 30 days of vitamin D₃ treatment. Furthermore, the DM state affected systemic enzymes, with no effect on the central enzymes hydrolyzing extracellular nucleotides and nucleosides. Vitamin D₃ treatment positively regulated ectonucleotidase (NTPDase and 5'-nucleotidase) activity, E-ADA, and the purinergic receptors as a mechanism to prevent oxidative damage in the cerebral cortex of T1DM rats. A neuroprotector effect of vitamin D₃ through adenosine signaling was also observed, by regulating A1 and A_2A receptors proteins levels. The present findings suggest that purinergic signaling through vitamin D₃ modulation may be a novel alternative strategy for T1DM treatment, and may compensate for the negative changes in the central nervous system.

Psidium cattleianum fruit extract prevents systemic alterations in an animal model of type 2 diabetes mellitus: comparison with metformin effects

Objective: In this study, we aimed to determine the role of Psidium cattleianum extract (PCE) and compare its effects with those of metformin (Met) in an animal model with type 2 diabetes mellitus (T2DM).Methods: T2DM was induced in rats using a high-fat diet (HFD), followed by a single dose of streptozotocin (STZ). Met and PCE were administered intragastrically once a day throughout the experiment, and their effects on biochemical, inflammatory, oxidative, and histological parameters were evaluated.Results: Met and PCE prevented the increase in serum levels of glucose, total cholesterol (TC), triacylglycerol (TG), very low-density lipoprotein (VLDL) and interleukin-6 (IL-6) induced by T2DM, and restored redox homeostasis in the liver and brain. Met increased the serum levels of anti-inflammatory cytokine and interleukin-10 (IL-10). Furthermore, both treatments restored the liver and pancreas from marked cellular disorganisation, vacuolisation, and necrosis, with PCE being more effective than Met in recovering histological changes.Conclusion: PCE is a promising agent for the prevention of T2DM complications.

Neuroprotective Effect of Ponicidin Alleviating the Diabetic Cognitive Impairment: Regulation of Gut Microbiota

Cognitive impairment is a major complication of diabetes mellitus, which is caused by constitutive hyperglycaemia. Ponicidin is a diterpenoid isolated from a Chinese traditional herb (Rabdosia rubescens) and demonstrates the various pharmacological effects. The goal of this study was to scrutinise the neuroprotective effect of ponicidin against diabetic nephropathy (DN) induced by streptozotocin (STZ). Intraperitoneal administration of STZ (55 mg/kg) was used for the induction of diabetes and rats were received oral administration of ponicidin (5, 10 and 15 mg/kg) until 28 days. The body weight, food intake, water intake and blood glucose level were assessed at regular time interval. Plasma insulin level, antioxidant, inflammatory cytokines, apoptosis marker and faecal gut microbiota compositions were estimated. DN-induced group rats revealed the augmented glucose level, water intake, food intake and reduced body weight. Ponicidin significantly (P < 0.001) repressed the glucose level and water food intake and improved the body weight and plasma insulin. Ponicidin significantly (P < 0.001) repressed the malonaldehyde (MDA) level and boosted the level of glutathione (GSH), glutathione reductase (GR) and superoxide dismutase (SOD) in the brain and serum level. Ponicidin significantly (P < 0.001) repressed the level of interleukin-1β (IL-1β), tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6) and enhanced the level of interleukin-4 (IL-4), interleukin-10 (IL-10) in the brain and serum level. DN group rats exhibited the enhanced relative abundance of Firmicutes, along with enhancing the Firmicutes/Bacteroidetes ratio and repressing the Bacteroidetes relative abundance. Ponicidin effectually restored the relative abundance of Allobaculum, Lactobacillus and Ruminococcus genera. Our findings clearly demonstrated that ponicidin has a neuroprotective effect against diabetic cognitive impairment through modulating the gut microbiome.

Altered Functional Connectivity Density in Type 2 Diabetes Mellitus with and without Mild Cognitive Impairment

Although disturbed functional connectivity is known to be a factor influencing cognitive impairment, the neuropathological mechanisms underlying the cognitive impairment caused by type 2 diabetes mellitus (T2DM) remain unclear. To characterize the neural mechanisms underlying T2DM-related brain damage, we explored the altered functional architecture patterns in different cognitive states in T2DM patients. Thirty-seven T2DM patients with normal cognitive function (DMCN), 40 T2DM patients with mild cognitive impairment (MCI) (DMCI), and 40 healthy controls underwent neuropsychological assessments and resting-state functional MRI examinations. Functional connectivity density (FCD) analysis was performed, and the relationship between abnormal FCD and clinical/cognitive variables was assessed. The regions showing abnormal FCD in T2DM patients were mainly located in the temporal lobe and cerebellum, but the abnormal functional architecture was more extensive in DMCI patients. Moreover, in comparison with the DMCN group, DMCI patients showed reduced long-range FCD in the left superior temporal gyrus (STG), which was correlated with the Rey auditory verbal learning test score in all T2DM patients. Thus, DMCI patients show functional architecture abnormalities in more brain regions involved in higher-level cognitive function (executive function and auditory memory function), and the left STG may be involved in the neuropathology of auditory memory in T2DM patients. These findings provide some new insights into understanding the neural mechanisms underlying T2DM-related cognitive impairment.

Diabetic Encephalopathy in a Preclinical Experimental Model of Type 1 Diabetes Mellitus: Observations in Adult Female Rat

Patients affected by diabetes mellitus (DM) show diabetic encephalopathy with an increased risk of cognitive deficits, dementia and Alzheimer's disease, but the mechanisms are not fully explored. In the male animal models of DM, the development of cognitive impairment seems to be the result of the concomitance of different processes such as neuroinflammation, oxidative stress, mitochondrial dysfunction, and aberrant synaptogenesis. However, even if diabetic encephalopathy shows some sex-dimorphic features, no observations in female rats have been so far reported on these aspects. Therefore, in an experimental model of type 1 DM (T1DM), we explored the impact of one month of pathology on memory abilities by the novel object recognition test and on neuroinflammation, synaptogenesis and mitochondrial functionality. Moreover, given that steroids are involved in memory and learning, we also analysed their levels and receptors. We reported that memory dysfunction can be associated with different features in the female hippocampus and cerebral cortex. Indeed, in the hippocampus, we observed aberrant synaptogenesis and neuroinflammation but not mitochondrial dysfunction and oxidative stress, possibly due to the results of locally increased levels of progesterone metabolites (i.e., dihydroprogesterone and allopregnanolone). These observations suggest specific brain-area effects of T1DM since different alterations are observed in the cerebral cortex.

Type 2 Diabetes Mellitus and Alzheimer's Disease: Shared Molecular Mechanisms and Potential Common Therapeutic Targets

The global prevalence of diabetes mellitus and Alzheimer's disease is increasing alarmingly with the aging of the population. Numerous epidemiological data suggest that there is a strong association between type 2 diabetes and an increased risk of dementia. These diseases are both degenerative and progressive and share common risk factors. The amyloid cascade plays a key role in the pathophysiology of Alzheimer's disease. The accumulation of amyloid beta peptides gradually leads to the hyperphosphorylation of tau proteins, which then form neurofibrillary tangles, resulting in neurodegeneration and cerebral atrophy. In Alzheimer's disease, apart from these processes, the alteration of glucose metabolism and insulin signaling in the brain seems to induce early neuronal loss and the impairment of synaptic plasticity, years before the clinical manifestation of the disease. The large amount of evidence on the existence of insulin resistance in the brain during Alzheimer's disease has led to the description of this disease as "type 3 diabetes". Available animal models have been valuable in the understanding of the relationships between type 2 diabetes and Alzheimer's disease, but to date, the mechanistical links are poorly understood. In this non-exhaustive review, we describe the main molecular mechanisms that may link these two diseases, with an emphasis on impaired insulin and IGF-1 signaling. We also focus on GSK3β and DYRK1A, markers of Alzheimer's disease, which are also closely associated with pancreatic β-cell dysfunction and type 2 diabetes, and thus may represent common therapeutic targets for both diseases.

Insulin Resistance and Cognitive Impairment: Evidence From Neuroimaging

Insulin is a peptide well known for its role in regulating glucose metabolism in peripheral tissues. Emerging evidence from human and animal studies indicate the multifactorial role of insulin in the brain, such as neuronal and glial metabolism, glucose regulation, and cognitive processes. Insulin resistance (IR), defined as reduced sensitivity to the action of insulin, has been consistently proposed as an important risk factor for developing neurodegeneration and cognitive impairment. Although the exact mechanism of IR-related cognitive impairment still awaits further elucidation, neuroimaging offers a versatile set of novel contrasts to reveal the subtle cerebral abnormalities in IR. These imaging contrasts, including but not limited to brain volume, white matter (WM) microstructure, neural function and brain metabolism, are expected to unravel the nature of the link between IR, cognitive decline, and brain abnormalities, and their changes over time. This review summarizes the current neuroimaging studies with multiparametric techniques, focusing on the cerebral abnormalities related to IR and therapeutic effects of IR-targeting treatments. According to the results, brain regions associated with IR pathophysiology include the medial temporal lobe, hippocampus, prefrontal lobe, cingulate cortex, precuneus, occipital lobe, and the WM tracts across the globe. Of these, alterations in the temporal lobe are highly reproducible across different imaging modalities. These structures have been known to be vulnerable to Alzheimer's disease (AD) pathology and are critical in cognitive processes such as memory and executive functioning. Comparing to asymptomatic subjects, results are more mixed in patients with metabolic disorders such as type 2 diabetes and obesity, which might be attributed to a multifactorial mechanism. Taken together, neuroimaging, especially MRI, is beneficial to reveal early abnormalities in cerebral structure and function in insulin-resistant brain, providing important evidence to unravel the underlying neuronal substrate that reflects the cognitive decline in IR. EVIDENCE LEVEL: 5 TECHNICAL EFFICACY: Stage 2.

Antioxidant, antidiabetic, and anticholinesterase potential of Chenopodium murale L. extracts using in vitro and in vivo approaches

In this study, Chenopodium murale Linn. extracts have been evaluated for its in vitro antioxidant, enzyme inhibition, and in vivo neuropharmacological properties in streptozotocin (STZ)-induced memory impairment in rat model. First, the plant was subjected to extraction and fractionation, then quantitative phytochemical analysis was performed to estimate the major phytochemical groups in the extract where high amounts of phenolics and saponins were detected in crude and chloroform extract. The highest total phenolic contents, total flavonoid contents, and total tannin content were also recorded in crude extract and chloroform fraction. The in vitro antioxidant potential of chloroform fraction was high with IC50 value of 41.78 and 67.33 μg/mL against DPPH and ABTS radicals, respectively, followed by ethyl acetate fraction. The chloroform fraction (ChMu-Chf) also exhibited potent activity against glucosidase with IC50 of 89.72 ± 0.88 μg/mL followed by ethyl acetate extract (ChMu-Et; IC50 of 140.20 ± 0.98 μg/mL). ChMu-Chf again exhibited potent activity against acetylcholinesterase (AChE) with IC50 of 68.91 ± 0.87 μg/mL followed by ChMu-Et with IC50 of 78.57 ± 0.95 μg/mL. In vivo memory impairment was assessed using the novel object discrimination task, Y-maze, and passive avoidance task. Ex vivo antioxidant enzyme activities and oxidative stress markers like catalase, superoxide dismutase (SOD), malondialdehyde, and glutathione were quantified, and the AChE activity was also determined in the rat brain. No significant differences were observed amongst all the groups treated with crude, chloroform, and ethyl acetate in comparison with positive control donepezil group in connection to initial latency; whereas, the STZ diabetic group displayed a significant fall in recall and retention capability. The blood glucose level was more potently lowered by chloroform extract. The crude extract also increased the SOD level significantly in the brain of the treated rat by 8.01 ± 0.51 and 8.19 ± 0.39 units/mg at 100 and 200 mg/kg body weight (P < 0.01, n = 6), whereas the chloroform extract increased the SOD level to 9.41 ± 0.40 and 9.72 ± 0.51 units/mg, respectively, at 75 and 150 mg/kg body weight as compared to STZ group. The acetylcholine level was also elevated to greater extent by chloroform fraction that might contain a potential inhibitor of acetylcholinesterase. Treatment with C. murale ameliorated cognitive dysfunction in behavioral study, and provided significant defense from neuronal oxidative stress in the brain of the STZ-induced diabetic rats. Thus C. murale Linn. could be an inspiring plant resource that needs to be further investigated for isolation of potential compounds in pure form and their evaluation as a potent neuropharmacological drug.

The Impact of Frailty on Traumatic Brain Injury Outcomes: An Analysis of 691 821 Nationwide Cases

BACKGROUND

Frailty, a decline in physiological reserve, prognosticates poorer outcomes for several neurosurgical conditions. However, the impact of frailty on traumatic brain injury outcomes is not well characterized.

OBJECTIVE

To analyze the association between frailty and traumatic intracranial hemorrhage (tICH) outcomes in a nationwide cohort.

METHODS

We identified all adult admissions for tICH in the National Trauma Data Bank from 2007 to 2017. Frailty was quantified using the validated modified 5-item Frailty Index (mFI-5) metric (range = 0-5), with mFI-5 ≥2 denoting frailty. Analyzed outcomes included in-hospital mortality, favorable discharge disposition, complications, ventilator days, and intensive care unit (ICU) and total length of stay (LOS). Multivariable regression assessed the association between mFI-5 and outcomes, adjusting for patient demographics, hospital characteristics, injury severity, and neurosurgical intervention.

RESULTS

A total of 691 821 tICH admissions were analyzed. The average age was 57.6 years. 18.0% of patients were frail (mFI-5 ≥ 2). Between 2007 and 2017, the prevalence of frailty grew from 7.9% to 21.7%. Frailty was associated with increased odds of mortality (odds ratio [OR] = 1.36, P < .001) and decreased odds of favorable discharge disposition (OR = 0.72, P < .001). Frail patients exhibited an elevated rate of complications (OR = 1.06, P < .001), including unplanned return to the ICU (OR = 1.55, P < .001) and operating room (OR = 1.17, P = .003). Finally, frail patients experienced increased ventilator days (+12%, P < .001), ICU LOS (+11%, P < .001), and total LOS (+13%, P < .001). All associations with death and disposition remained significant after stratification for age, trauma severity, and neurosurgical intervention.

CONCLUSION

For patients with tICH, frailty predicted higher mortality and morbidity, independent of age or injury severity.

Potential mechanisms underlying the association between type II diabetes mellitus and cognitive dysfunction in rats: a link between miRNA-21 and Resveratrol's neuroprotective action

Cognitive impairment is considered as a typical feature of neurodegenerative diseases in diabetes mellitus (DM). However, the exact link between cognitive dysfunction and diabetes mellitus is still vague. This study aims to investigate some of the mechanisms underlying cognitive impairment that associates diabetes mellitus and insulin resistance. We investigated the role of resveratrol as well on cognitive function in experimentally induced type 2 diabetes highlighting on its influence on the expression of brain miRNA 21. Resveratrol is a naturally occurring, biologically active compound that has numerous significant impacts on the body. Type 2 diabetes mellitus was induced by high fat diet followed a single dose of streptozotocin. Diabetic rats were treated with resveratrol for four weeks. Rats were sacrificed after neurobehavioral testing. Hippocampal tissues were used to assess expression of miRNA 21, GSK and oxidative stress markers. Serum samples were obtained to determine glucose levels, lipid profile and insulin levels. Hippocampal and serum AGEs were measured as well and HOMA IR was calculated. We detected memory impairment and disturbed insulin signaling in diabetic rats. These derangements were reversed by resveratrol treatment partially due to increased expression of miRNA-21. Our study pins the role of miRNA-21 in modulating brain insulin signaling and hence alleviating cognitive dysfunction accompanying diabetes mellitus.

Avaliação da incapacidade de indivíduos com diabetes mellitus: um estudo transversal com o WHODAS 2.0

RESUMO A diabetes mellitus (DM) causa diversas limitações funcionais, que podem impactar negativamente na vida pessoal e profissional do indivíduo, acarretando mais complicações e incapacidades. O objetivo do estudo foi identificar em quais domínios do World Health Organization Disability Assessment Schedule versão 2.0 (WHODAS 2.0) os indivíduos com DM apresentam as maiores incapacidades. Para tanto, foi realizado um estudo transversal com 111 pessoas com diagnóstico da doença, independentemente do tipo. Foram aplicados um questionário sociodemográfico e o WHODAS 2.0 com 36 questões, para avaliar as dificuldades apresentadas nos últimos 30 dias. A amostra foi composta predominantemente pelo sexo feminino (60,3%) e classificada como independente na comunidade (90,1%). A maior prevalência foi de indivíduos aposentados (35,1%). O domínio mobilidade apresentou o maior comprometimento (48±23), enquanto o domínio atividades de vida apresentou o menor comprometimento (28±13). Porém, para todos os domínios, o comprometimento ficou abaixo de 50, em uma escala que varia de 0 a 100. Todos os indivíduos com DM apresentaram alguma deficiência, havendo maior comprometimento do domínio relacionado à mobilidade.

Disability assessment of individuals with diabetes mellitus: a cross-sectional study with the WHODAS 2.0

ABSTRACT Diabetes mellitus (DM) causes several functional limitations, which can negatively affect the personal and professional life of individuals. This effect can lead to more complications and disabilities. This study aimed to analyze in which domains of the World Health Organization Disability Assessment Schedule version 2.0 (WHODAS 2.0) individuals with diabetes mellitus have the greatest disabilities. cross-sectional study was performed with 111 individuals with diabetes mellitus, of any type. A sociodemographic questionnaire and the WHODAS 2.0 with 36 questions were applied to assess individuals’ difficulties in the last 30 days. Most individuals were women (60.3%) and classified as independent in the community (90.1%). The highest prevalence was among retired individuals (35.1%). The mobility domain presented the highest impairment (48±23) whereas the life activities domain presented the lowest impairment (28±13). However, for all domains, the impairment was below 50 on a scale ranging from zero to 100. All individuals with diabetes mellitus showed some disability, but the greatest impairment was in the mobility domain.

Walnut Prevents Cognitive Impairment by Regulating the Synaptic and Mitochondrial Dysfunction via JNK Signaling and Apoptosis Pathway in High-Fat Diet-Induced C57BL/6 Mice

This study was conducted to evaluate the protective effect of Juglans regia (walnut, Gimcheon 1ho cultivar, GC) on high-fat diet (HFD)-induced cognitive dysfunction in C57BL/6 mice. The main physiological compounds of GC were identified as pedunculagin/casuariin isomer, strictinin, tellimagrandin I, ellagic acid-O-pentoside, and ellagic acid were identified using UPLC Q-TOF/MS analysis. To evaluate the neuro-protective effect of GC, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), 2′,7′-dichlorodihydrofluorecein diacetate (DCF-DA) analysis were conducted in H₂O₂ and high glucose-induced neuronal PC12 cells and hippocampal HT22 cells. GC presented significant cell viability and inhibition of reactive oxygen species (ROS) production. GC ameliorated behavioral and memory dysfunction through Y-maze, passive avoidance, and Morris water maze tests. In addition, GC reduced white adipose tissue (WAT), liver fat mass, and serum dyslipidemia. To assess the inhibitory effect of antioxidant system deficit, lipid peroxidation, ferric reducing antioxidant power (FRAP), and advanced glycation end products (AGEs) were conducted. Administration of GC protected the antioxidant damage against HFD-induced diabetic oxidative stress. To estimate the ameliorating effect of GC, acetylcholine (ACh) level, acetylcholinesterase (AChE) activity, and expression of AChE and choline acetyltransferase (ChAT) were conducted, and the supplements of GC suppressed the cholinergic system impairment. Furthermore, GC restored mitochondrial dysfunction by regulating the mitochondrial ROS production and mitochondrial membrane potential (MMP) levels in cerebral tissues. Finally, GC ameliorated cerebral damage by synergically regulating the protein expression of the JNK signaling and apoptosis pathway. These findings suggest that GC could provide a potential functional food source to improve diabetic cognitive deficits and neuronal impairments.

Nonalcoholic Fatty Liver Disease and Risk of Dementia: A Population-Based Cohort Study

BACKGROUND AND OBJECTIVES

Nonalcoholic fatty liver disease (NAFLD) and dementia share common risk factors including metabolic disorders. However, whether NAFLD is associated with dementia risk is unclear. We investigated the association between NAFLD and dementia risk as well as the role of cardiovascular complications including heart disease and stroke.

METHODS

In this population-based matched cohort study, we identified all Swedish patients aged 65 years or older with NAFLD identified from the National Patient Register (NPR) between 1987 and 2016. These were matched with up to 10 reference individuals from the general population on age, sex, and municipality at the year of diagnosis. Incident dementia diagnosis was derived from the NPR or the Cause of Death Register until 2016. Adjusted hazard ratios (aHRs) and 95% CIs were estimated with Cox regression models.

RESULTS

A total of 2,898 patients with NAFLD and 28,357 matched controls were identified (median age at entry, interquartile range [IQR], 70 [8]; 55.1% female). During a median follow-up of 5.5 years (IQR: 8.5 years), 145 (5.0%) patients with NAFLD and 1,291 (4.6%) reference individuals were diagnosed with dementia. Compared with the reference individuals, patients with NAFLD had higher rates of dementia (aHR 1.38, 95% CI 1.10-1.72) and vascular dementia (aHR 1.44, 95% CI 0.96-2.23, p = 0.07). Comorbid NAFLD and either heart disease (aHR 1.50 95% 1.08-2.05) or stroke (aHR 2.60 95% CI 1.95-3.47) conferred a greater risk of dementia.

DISCUSSION

NAFLD had a modest association with increased rates of dementia. This was stronger among patients with NAFLD diagnosed with cardiovascular comorbidities.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that nonalcoholic fatty liver disease is associated with the development of vascular and nonvascular dementia.

Altered gray matter volume in children with newly diagnosed type 1 diabetes mellitus

BACKGROUND

Type 1 diabetes mellitus (T1DM) affects the development of cognitive function in children, which may be due to deficits in brain structures or functions. It is unclear whether children with T1DM experience alterations in the gray matter (GM) structure at the initial stages of the disease. This study investigated GM structure alterations in children with newly diagnosed T1DM.

METHODS

Based on 3D T1-weighted MR images, we investigated the gray matter volume (GMV) of 35 newly diagnosed T1DM children and 35 age- and sex-matched healthy controls using voxel-based morphometry. The brain regions with significant differences in GMV between the newly diagnosed T1DM children and the controls were extracted and the correlation with clinical data was assessed.

RESULTS

Compared with the control group, children with newly diagnosed T1DM had a lower GMV in the right inferior and middle temporal gyri, right lingual gyrus, and left superior frontal gyrus. In T1DM subjects, the GMV of the right middle temporal gyrus was positively correlated with IQ but was negatively correlated with HbA1c.

CONCLUSIONS

Our findings provide compelling evidence that GM abnormalities occur during early disease stages in T1DM children, which may be a potential neurobiological mechanism underlying cognitive deficits.

IMPACT

Using an efficient method to analyze gray matter changes in T1DM is very important. The anterior, posterior, and temporal brain regions are susceptible to T1DM in children. Recent glucose variability may affect regional gray matter volume in children with newly diagnosed T1DM. Structural changes were documented in the gray matter of the brain even at the early stages of the disease in children with T1DM.

Neuroprotective Effects of Treadmill Exercise in Hippocampus of Ovariectomized and Diabetic Rats

To determine detrimental effects of estrogen and insulin deficiencies on hippocampus, we examined apoptosis-induced neuronal damage and cholinergic system in ovariectomized and/or diabetic rat hippocampus. Possible neuroprotective effects of treadmill exercise were also investigated. Adult female Wistar rats were randomly divided into four groups (n = 5 rats/group) as follows: control, ovariectomized (Ovx), diabetic (Dia, streptozotocin (STZ) 60 mg/kg; i.p.), and Ovx + Dia groups. Each group was further subdivided into exercise and non-exercise groups. Animals in exercise groups were subjected to treadmill training, while those in non-exercise groups were placed on the stationary treadmill for 4 weeks (5 days/week). Apoptosis-related protein levels (i.e. Bax, Bcl-2, and caspase-3), number of survived neurons, and acetylcholinesterase (AChE) activity in the hippocampus were measured using Western blotting, Cresyl Violet staining, and Ellman assay, respectively. Both ovariectomy and diabetes increased expression of Bax and caspase-3 and decreased expression of Bcl-2 at protein levels. In addition, a significant decrease in the number of survived neurons was observed in both Ovx and Dia groups, while AChE activity was lower only in the Dia group. The Ovx + Dia group showed stronger apoptosis-induced neuropathology and inhibition of AChE activity. Treadmill exercise attenuated apoptosis-induced neuropathology in the Ovx and Dia groups and recovered AChE activity in the Dia group. Neuroprotective effects of treadmill exercise were mediated by inhibition of apoptosis. Moderate exercise protocol had no beneficial anti-apoptotic and neuroprotective effects in ovariectomized-diabetic rats.

Neuroprotective Effect and Possible Mechanisms of Berberine in Diabetes-Related Cognitive Impairment: A Systematic Review and Meta-Analysis of Animal Studies

Berberine, the main bioactive component of Coptis chinensis Franch., is widely used in the treatment of diabetes. Previous studies have reported that berberine supplementation may play a multitarget therapeutic role in diabetes-related cognitive impairment (DCI). This systematic review and meta-analysis evaluated the effect and possible mechanisms of berberine in animal models of DCI. Relevant studies were searched through PubMed, Web of Science, Embase, and three Chinese databases (CNKI, Wanfang, and VIP) until March 2022. Twenty studies involving 442 animals were included, and SYRCLE’s risk of bias tool was used to assess methodological quality. The statistical analysis was performed using STATA 15.0 to calculate the weighted standard mean difference (SMD) with a 95% confidence interval (CI). The fasting blood glucose (FBG) and Morris water maze test (MWM) were the main outcomes to be analyzed. The overall results showed that berberine could significantly improve FBG, escape latency, the times of crossing the platform, the time spent in the target quadrant, serum insulin, 2hBG of oral glucose tolerance test (OGTT), amyloid β (Aβ), acetylcholinesterase (AChE), oxidative stress, and inflammation levels. The present meta-analysis demonstrated that berberine could not only lower blood glucose levels but also improve learning and memory in DCI animal models, which might involve regulating glucose and lipid metabolism, improving insulin resistance, anti-oxidation, anti-neuroinflammation, inhibiting endoplasmic reticulum (ER) stress; and improving the cholinergic system. However, additional attention should be paid to these outcomes due to the significant heterogeneity.