Cognition and synaptic plasticity in diabetes mellitus

Altered cerebellar activity and cognitive deficits in Type 2 diabetes: Insights from resting-state fMRI

OBJECTIVE

To investigate alterations in brain activity in patients with Type 2 Diabetes and explore the relationship between altered regions and neuropsychological performances.

METHODS

A total of 36 patients with Type 2 Diabetes and 40 age- and education-matched healthy controls were recruited for this case-control study. All participants underwent resting-state functional magnetic resonance imaging (Resting-state fMRI) and neuropsychological tests. The neuropsychological scales included the Auditory Verbal Learning Test (AVLT), Shape Trajectory Test B (STT-B), Hamilton Anxiety Scale (HAMA), Hamilton Depression Scale (HAMD), and Boston Naming Test (BNT), Symbol Digit Modality Test (SDMT), Regional homogeneity (ReHo) and the amplitude of low-frequency fluctuations (ALFF) were used to assess differences in spontaneous regional brain activity. For functional connectivity (FC) analyses, the differences identified among the groups were selected as seed regions. Then, the correlations between neuropsychological scale scores (AVLT, HAMA, HAMD, STT-B, BNT, and SDMT) and ALFF/ReHo values were specifically analyzed in the focal regions that exhibited significant alterations between the T2DM and control groups, as detailed in Tables 2 and 3.

RESULTS

Patients with Type 2 Diabetes exhibited significantly higher ALFF values in the superior lobe of the cerebellum, specifically in the left cerebellar crus I (Cerebellum_Crus I_L), left cerebellar lobule VI (Cerebellum_6_L), and left cerebellar lobule IV-V (Cerebellum_4_5_L). Additionally, they exhibited elevated ReHo values in the Cerebellum_Crus I_L and Cerebellum_6_L. The findings were statistically significant with a family-wise error-corrected, cluster-level p-value of less than 0.05. However, the FC analysis was not significant. AVLT scores were significantly lower in the diabetes group. The correlation analysis demonstrated a negative association between ALFF values of the Cerebellum_6_L and AVLT scores (R2 = 0.1375, P < 0.001). The ReHo values within the Cerebellum_6_L also exhibited a negative association with AVLT scores (R2 = 0.0937, P = 0.007).

CONCLUSION

Patients with Type 2 Diabetes showed abnormal neural activities in diverse cerebellar regions mainly related to cognitive functions. This provides supplementary information to deepen our insight into the neural mechanisms by which Type 2 Diabetes affects the functional activity of the brain's posterior circulation, as well as the potential association of these changes with cognitive impairment.

Immediate effects of visual feedback on the accuracy of foot landing adjustments in older people with diabetes mellitus: A cross-sectional study

Diabetes Mellitus in older adults reduces the accuracy of foot landing adjustments and increases the risk of falling. This study investigated whether targeted visual feedback enhances the accuracy of the foot landing in older participants with diabetes. Forty-eight volunteers in three groups of young, healthy older and older adults with diabetes participated. During treadmill walking, Nexus Vicon software streamed real-time orientation data of two markers on the first toes into MATLAB scripts through a Visual3D server. The system visualised real-meaningful step length or minimum toe clearance (MTC) in each step on a monitor in front of a treadmill at eye level. Participants responded to four subject-specific step-length (±10% mean baseline step length) or MTC targets (3.5 and 5.5 cm higher than the mean baseline MTC). One target was displayed every 10 steps and removed after 10 steps when participants walked without seeing any target, then a new or the same target appeared and stayed on for another 10 steps. Tasks were increasing or decreasing baseline step length or increasing the baseline MTC in response to virtual targets. The accuracy (absolute error) of each step adjustment in each 10-step block with a target was calculated. The mean accuracy of Step 1 and the mean accuracy of Steps 2-10 were measured and compared within and between groups using three-way ANOVA tests. Errors significantly differed between conditions (Step 1 and Steps 2-10) in all groups. All groups showed reduced errors in Step 1 during Steps 2-10. Among groups, the group with diabetes presented the greatest errors in Step 1 and Steps 2-10. These findings suggest that meaningful visual feedback about spatial gait parameters (step length, MTC) can improve foot-landing accuracy in older participants with diabetes, highlighting its potential as a training tool to prevent falls in this high-risk population.

Intranasal insulin enhances resting-state functional connectivity in Type 2 Diabetes

Type 2 diabetes mellitus (T2DM) affects cognition and resting-state functional connectivity (rsFC). Intranasal insulin (INI) has emerged as a potential treatment for T2DM-related cognitive decline. We aimed to evaluate the effect of INI treatment on rsFC with medio-prefrontal (mPFC) and left/right hippocampus (lHPC/rHPC), and their relationship with the cognition, hemoglobin A1c (HbA1c), and homeostatic model assessment of insulin resistance (HOMA-IR) and walking speed. An MRI sub-study of the MemAID trial was conducted, involving a 24-week treatment with either intranasal insulin or placebo. Blood oxygen level-dependent (BOLD) functional MRI (fMRI) images were acquired on eighteen DM subjects at baseline and eleven DM subjects (eight DM-INI patients and three DM-Placebo) at the end-of-treatment. Compared to DM-Placebo treated subjects, DM-INI patients showed increased mPFC-postcentral rsFC, lHPC-frontal rsFC, lHPC-postcentral rsFC, rHPC-frontal rsFC, and lHPC-mPFC rsFC (p < 0.05). The decreased HOMA-IR, which was observed in the MemAID trial, was associated with increased mPFC-basal ganglia rsFC (p < 0.05). This sub-study provides insights into potential mechanisms of INI effects on rsFC that require validation in a larger trial.

Deciphering the NLRP3 inflammasome in diabetic encephalopathy: Molecular insights and emerging therapeutic targets

Diabetic encephalopathy (DE) is a neurological complication characterized by neuroinflammation, cognitive impairment, and memory decline, with its pathogenesis closely linked to the activation of the NLRP3 inflammasome. As a central regulator of the innate immune system, the NLRP3 inflammasome plays a pivotal role in DE progression by mediating neuroinflammation, pyroptosis, mitochondrial dysfunction, oxidative stress, endoplasmic reticulum (ER) stress, and microglial polarization. This review systematically explores the molecular mechanisms by which the NLRP3 inflammasome contributes to DE, focusing on its role in neuroinflammatory cascades and neuronal damage, as well as the diabetes-associated physiological changes that exacerbate DE pathogenesis. Furthermore, we summarize emerging therapeutic strategies targeting the NLRP3 inflammasome, including small-molecule inhibitors and bioactive compounds derived from traditional herbal medicine, highlighting their potential for DE treatment. These findings not only advance our understanding of DE but also provide a foundation for developing NLRP3-targeted pharmacological interventions.

The overexpression of miR-146a in hippocampal microglia via IRAK1/TRAF6/NF-κB pathway improves cognitive function in diabetic mice

BACKGROUND AND OBJECTIVE

Diabetic encephalopathy (DEP), a central nervous system complication of diabetes, is primarily characterized by cognitive dysfunction. Despite its high prevalence and significant risks, the pathogenesis remains poorly understood. This study investigates the effects and mechanisms of miR-146a on cognitive function in DEP mice.

METHODS

Type 2 diabetic mice models were established by feeding a high-fat diet and administering a low-dose of streptozotocin. And the Morris water maze test was conducted to assess the learning and memory. The adeno-associated virus was delivered into hippocampus by stereotactic injection to overexpress miR-146a in microglia. The mRNA and protein expression levels were determined by quantitative real-time polymerase chain reaction, immunofluorescence, Western blot, and enzyme-linked immunosorbent assay.

RESULTS

DEP mice exhibited significantly reduced miR-146a expression in hippocampal microglia. This reduction was associated with elevated IRAK1, TRAF6, and NF-κB expression, increased markers of pro-inflammatory microglial phenotypes (CD86 and iNOS), and decreased markers of anti-inflammatory phenotypes (Arg-1 and CD206). Pro-inflammatory cytokines TNF-α and IL-6 were elevated, while anti-inflammatory IL-10 was reduced. Eventually, neuronal apoptosis and cognitive dysfunction were evident. Overexpression of miR-146a in hippocampal microglia reversed these molecular and phenotypic abnormalities, decreased neuronal apoptosis, and significantly improved cognitive performance in diabetic mice.

CONCLUSION

Downregulation of miR-146a in hippocampal microglia disrupts immune homeostasis through the IRAK1/TRAF6/NF-κB pathway, contributing to DEP. Targeted overexpression of miR-146a restores immune homeostasis, reduces neuronal apoptosis, and ameliorates cognitive impairment.

Synthesis, structural insights and bio-evaluation of N-phenoxyethylisatin hydrazones as potent α-glucosidase inhibitors

Effective α-glucosidase inhibitors are vital for managing type 2 diabetes, emphasizing the need for novel and potent compounds. A series of novel N-phenoxyethylisatin hydrazones 1(a-l) have been synthesized and characterized by their spectral data, and in the case of 1l by its single crystal X-ray analysis. All the synthesized compounds were in vitro evaluated for their inhibition potential against the α-glucosidase enzyme. Interestingly, most of these compounds exhibited significant inhibitory activity against the α-glucosidase enzyme, with IC50 values ranging from 3.64 ± 0.13 to 94.89 ± 0.64 μM compared to the standard drug, acarbose (IC50 = 873.34 ± 1.67 μM). The compound 1e was found to be the most active compound of the series having an IC50 value of 3.64 ± 0.13 μM. Molecular docking studies revealed a binding score of -9.7 kcal mol-1 for 1e, slightly surpassing that of acarbose (-9.4 kcal mol-1). Unlike acarbose, which primarily relies on hydrogen bonding, the binding interactions of 1e are dominated by π-interactions. ADMET profiling confirmed favourable pharmacokinetics for these compounds, including good oral bioavailability, balanced hydrophilicity, and minimal predicted toxicity. These findings highlight the potential of these compounds as promising candidates for the development of more effective treatments for hyperglycemia.

Genome-wide Pleiotropy Analysis Reveals Shared Genetic Associations between Type 2 Diabetes Mellitus and Subcortical Brain Volumes

Type 2 diabetes mellitus (T2DM), a prevalent metabolic disorder marked by insulin resistance and hyperglycemia, has been linked to volumetric changes in subcortical regions, yet the genetic basis of this relationship remains unclear. We analyzed genome-wide association study summary data for T2DM and 14 subcortical volumetric traits, using MiXeR to quantify shared genetic architecture and applying conditional/conjunctional false discovery rate analyses to detect novel and shared genomic loci. Enrichment and gene expression analyses were subsequently performed to explore the biological functions and mechanisms of genes associated with these loci. We observed a substantial proportion of trait-influencing variants shared between T2DM and subcortical structures, with Dice coefficients ranging from 22.4% to 49.6%. Additionally, 70 distinct loci were identified as being jointly associated with T2DM and subcortical volumes, 5 and 22 of which were novel for T2DM and subcortical volumes, respectively. The 769 protein-coding genes mapped to these shared loci are enriched in metabolic and neurodevelopmental pathways and exhibit specific developmental trajectories, with 117 genes showing expression levels linked to both T2DM and subcortical structures. This study uncovered polygenic overlap between T2DM and subcortical structures, deepening our comprehension of the genetic factors linking metabolic disorders and brain health.

Exploring the cognitive impacts of diabetic neuropathy: a comprehensive review

Diabetic neuropathy (DPN) is known to affect various aspects of health, including cognitive function. This study explores how DPN influences cognitive performance and examines the interplay between DPN, gender differences, Alzheimer's Disease (AD), and the socioeconomic burden of neuropathic pain. The research involved a comprehensive review and analysis of 55 studies focusing on cognitive function in diabetic patients with and without DPN. Various cognitive assessments, including memory, processing speed, and olfactory function, were used to evaluate cognitive performance. Gender differences were analyzed in the context of cognitive impairment and neuropathic pain. Additionally, the relationship between peripheral neuropathy and AD was investigated through measures of nerve conduction velocities and amyloid protein deposits. The impact of physical and psychological factors on neuropathic pain and cognitive function was also examined. The findings indicate that diabetic patients with DPN exhibit more severe cognitive impairments compared to those without DPN and healthy controls. Cognitive deficits were particularly notable in memory and processing speed. Gender differences revealed that women with DPN experience more pronounced cognitive dysfunction and a higher incidence of painful neuropathy compared to men. Analysis of peripheral nerve conduction velocities and amyloid deposits suggested a link between neuropathy and AD. Furthermore, poor glycemic control emerged as a critical factor affecting both neuropathy and cognitive function. Psychological distress and socioeconomic factors were found to significantly influence the management and outcomes of neuropathic pain. The study underscores the complex interaction between DPN and cognitive impairment, highlighting the importance of integrated diagnostic and therapeutic approaches. The pronounced cognitive deficits in women and the link between DPN and AD emphasize the need for gender-specific and multifaceted treatment strategies. The socioeconomic impact of neuropathic pain and the role of psychological factors in exacerbating pain and cognitive decline suggest that comprehensive management plans should address both physical and mental health aspects to improve overall patient outcomes.

Increased risk of dementia in Type 1 diabetes: A systematic review with meta-analysis

This systematic review and meta-analysis aimed to synthesize evidence on the association between Type 1 diabetes mellitus (Type 1 diabetes) and dementia risk. A systematic search of CINAHL, EMBASE, MEDLINE, PSYCINFO, and Web of Science databases identified 19 relevant studies for inclusion. Studies, published in English, were assessed for quality using the QUADAS-2 tool, and data were extracted for synthesis. A meta-analysis of six studies reporting hazard ratios (HR) for dementia risk in individuals with Type 1 diabetes versus controls was conducted. The pooled HR for all-cause dementia was 1.50 (95 % CI: 1.25-1.80, p < 0.001), indicating a 50 % increased risk of dementia in people with Type 1 diabetes compared to controls. This review provides robust evidence linking Type 1 diabetes to increased dementia risk and highlights the need for targeted screening and preventive strategies for this population. Further research is necessary to explore the mechanisms underlying the association between Type 1 diabetes and dementia.

Lipin1 ameliorates cognitive ability of diabetic encephalopathy via regulating Ca2+ transfer through mitochondria-associated endoplasmic reticulum membranes

Diabetic encephalopathy (DE) is a common central nervous system complication resulting from diabetes mellitus (DM). While the exact pathogenesis remains unclear, a homeostatic imbalance of mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs) within neurons has been shown to be closely associated with the dysfunctional cognitive pathology of this condition. Our previous work has revealed that phosphatidate phosphatase Lipin1 plays a critical role in the cognitive processes of DE via regulating mitochondrial function. In this study, we reported that the integrity of neuronal MAMs was disrupted in DE mice, which was accompanied by a decrease in the expression of hippocampal Lipin1. With a knock-down of hippocampal Lipin1 in normal mice, ER stress was induced, MAMs structures were impaired and Ca2+ transfer was suppressed. Such effects resulted in mitochondrial dysfunction, synaptic plasticity impairments, and finally cognitive dysfunctions. In contrast, an up-regulation of hippocampal Lipin1 in the DE model partially alleviated these dysfunctions. These results suggest that Lipin1 may ameliorate the cognitive dysfunctions associated with DE via regulating Ca2+ transfers through MAMs. Therefore, targeting Lipin1 may serve as a therapeutic strategy for the clinical treatment of DE.

Leptin-dopamine interactions: unveiling the common link between type-2 diabetes and neuropsychiatric comorbidities

Clinical evidence highlights the central nervous system as a key target in type-2 diabetes-related complications, yet the mechanisms underlying the increased prevalence of mood disorder issues, mainly depression, in patients with diabetes remain poorly understood. Leptin, an adiposity hormone known for its role in energy homeostasis, has been shown to improve insulin sensitivity and regulate blood glucose levels in diabetic populations. Beyond its metabolic effects, leptin also has the potential to mitigate psychiatric complications such as depression and anxiety. Notably, leptin receptors are predominantly expressed on dopamine (DA) neurons in the brain, hinting that leptin may orchestrate DA activity by serving as its endogenous modulator. This review examines the role of leptin as a potential common link between type-2 diabetes and mood disorders, particularly through its effects on DA function. This article proposes defective leptin signaling as a vital mechanism contributing to psychiatric complications and compromised DA functions in type-2 diabetes, highlighting leptin as a promising therapeutic target for addressing metabolic and psychiatric comorbidities.

Efficacy and Safety of Agomelatine in Depressed Patients with Diabetes: A Systematic Review and Meta-Analysis

Major depressive disorder (MDD) and diabetes mellitus (DM) remain among the most prevalent diseases and the most significant challenges faced by medicine in the 21st century. The frequent co-occurrence and bidirectional relationship between the two conditions necessitates the identification of treatment strategies that benefit both. The purpose of this study was to systematically review and meta-analyze data on the efficacy and safety of agomelatine (AGO) in the treatment of patients with depression with comorbid diabetes to explore its potential mechanism of action in both diseases and its impact on diabetic parameters. Following PRISMA guidelines, a total of 11 studies were identified, both preclinical and clinical trials. Agomelatine has shown great potential as a treatment option for patients with diabetes and comorbid depression and anxiety. In addition to improving depressive and anxiety symptoms, it is also beneficial in glycemic control. A meta-analysis demonstrated a statistically significant reduction in glycated hemoglobin (HbA1C) and fasting blood glucose (FBG) levels following AGO administration over a period of 8-16 weeks. The administration of agomelatine was found to result in a significantly greater reduction in HbA1C than that observed with the selective serotonin reuptake inhibitor (SSRI) medications (namely fluoxetine, sertraline, and paroxetine) during 12-16 weeks of therapy. Furthermore, AGO has been found to be at least as effective as SSRIs in reducing depressive symptoms and more effective than SSRIs in reducing anxiety symptoms. The safety of such treatment is similar to SSRIs; no severe adverse events were reported, and the incidence of some side effects, such as insomnia and sexual dysfunction, are even less often reported. Particularly promising is also its potential action in improving some diabetic complications reported in preclinical trials. This might be through mechanisms involving the reduction in oxidative stress, anti-inflammatory effects, and potentially noradrenergic or NMDA receptor modulation. Further clinical studies on larger sample sizes, as well as elucidating its mechanisms of action, especially in the context of diabetic complications, are needed. Research should also focus on identifying the patient subpopulations most likely to benefit from agomelatine treatment.

Morphological evidence for the potential protective effects of curcumin and Garcinia kola against diabetes in the rat hippocampus

This research investigated the effects of sciatic nerve transection and diabetes on the hippocampus, and the protective effects of Garcinia kola and curcumin. Thirty-five adults male Wistar albino rats were divided into five groups: a control group (Cont), a transected group (Sham group), a transected + diabetes mellitus group (DM), a transected + diabetes mellitus + Garcinia kola group (DM + GK), and a transected + DM + curcumin group (DM + Cur), each containing seven animals. The experimental diabetes model was created with the intraperitoneal injection of a single dose of streptozotocin. No procedure was applied to the Cont group, while sciatic nerve transection was performed on the other groups. Garcinia kola was administered to the rats in DM + GK, and curcumin to those in DM + Cur. Cardiac perfusion was performed at the end of the experimental period. Brain tissues were dissected for stereological, histopathological, and immunohistochemical evaluations. The volume ratios of hippocampal layers to the entire hippocampus volume were compared between the groups. Anti-S100, anti-caspase 3, and anti-SOX 2 antibodies were used for immunohistochemical analysis. No statistically significant difference was observed in the volume ratios of the four hippocampal layers. However, the volume ratio of the stratum lucidum was higher in the Sham, DM, and DM + Cur groups compared to the Cont group. While curcumin exhibited a protective effect on hippocampal tissue following diabetes induction, Garcinia kola had only a weak protective effect. Increased cell density and nuclear deterioration due to diabetes and nerve transection can be partially ameliorated by treatment with Garcinia kola and curcumin.

Progress in the Pathogenesis of Diabetic Encephalopathy: The Key Role of Neuroinflammation

Diabetic encephalopathy (DE) is a severe complication that occurs in the central nervous system (CNS) and leads to cognitive impairment. DE involves various pathophysiological processes, and its pathogenesis is still unclear. This review summarised current research on the pathogenesis of diabetic encephalopathy, which involves neuroinflammation, oxidative stress, iron homoeostasis, blood-brain barrier disruption, altered gut microbiota, insulin resistance, etc. Among these pathological mechanisms, neuroinflammation has been focused on. This paper summarises some of the molecular mechanisms involved in neuroinflammation, including the Mammalian Target of Rapamycin (mTOR), Lipocalin-2 (LCN-2), Pyroptosis, Advanced Glycosylation End Products (AGEs), and some common pro-inflammatory factors. In addition, we discuss recent advances in the study of potential therapeutic targets for the treatment of DE against neuroinflammation. The current research on the pathogenesis of DE is progressing slowly, and more research is needed in the future. Further study of neuroinflammation as a mechanism is conducive to the discovery of more effective treatments for DE in the future.

Impairment of synaptic plasticity in the primary somatosensory cortex in a model of diabetic mice

Type 1 and type 2 diabetic patients experience alterations in the Central Nervous System, leading to cognitive deficits. Cognitive deficits have been also observed in animal models of diabetes such as impaired sensory perception, as well as deficits in working and spatial memory functions. It has been suggested that a reduction of insulin-like growth factor-I (IGF-I) and/or insulin levels may induce these neurological disorders. We have studied synaptic plasticity in the primary somatosensory cortex of young streptozotocin (STZ)-diabetic mice. We focused on the influence of reduced IGF-I brain levels on cortical synaptic plasticity. Unit recordings were conducted in layer 2/3 neurons of the primary somatosensory (S1) cortex in both control and STZ-diabetic mice under isoflurane anesthesia. Synaptic plasticity was induced by repetitive whisker stimulation. Results showed that repetitive stimulation of whiskers (8 Hz induction train) elicited a long-term potentiation (LTP) in layer 2/3 neurons of the S1 cortex of control mice. In contrast, the same induction train elicited a long-term depression (LTD) in STZ-diabetic mice that was dependent on NMDA and metabotropic glutamatergic receptors. The reduction of IGF-I brain levels in diabetes could be responsible of synaptic plasticity impairment, as evidenced by improved response facilitation in STZ-diabetic mice following the application of IGF-I. This hypothesis was further supported by immunochemical techniques, which revealed a reduction in IGF-I receptors in the layer 2/3 of the S1 cortex in STZ-diabetic animals. The observed synaptic plasticity impairments in STZ-diabetic animals were accompanied by decreased performance in a whisker discrimination task, along with reductions in IGF-I, GluR1, and NMDA receptors observed in immunochemical studies. In conclusion, impaired synaptic plasticity in the S1 cortex may stem from reduced IGF-I signaling, leading to decreased intracellular signal pathways and thus, glutamatergic receptor numbers in the cellular membrane.

WNKs regulate mouse behavior and alter central nervous system glucose uptake and insulin signaling

Certain areas of the brain involved in episodic memory and behavior, such as the hippocampus, express high levels of insulin receptors and glucose transporter-4 (GLUT4) and are responsive to insulin. Insulin and neuronal glucose metabolism improve cognitive functions and regulate mood in humans. Insulin-dependent GLUT4 trafficking has been extensively studied in muscle and adipose tissue, but little work has demonstrated either how it is controlled in insulin-responsive brain regions or its mechanistic connection to cognitive functions. In this study, we demonstrate that inhibition of WNK (With-No-lysine (K)) kinases improves learning and memory in mice. Neuronal inhibition of WNK enhances in vivo hippocampal glucose uptake. Inhibition of WNK enhances insulin signaling output and insulin-dependent GLUT4 trafficking to the plasma membrane in mice primary neuronal cultures and hippocampal slices. Therefore, we propose that the extent of neuronal WNK kinase activity has an important influence on learning, memory and anxiety-related behaviors, in part, by modulation of neuronal insulin signaling.

Acyl pyrazole sulfonamides as new antidiabetic agents: synthesis, glucosidase inhibition studies, and molecular docking analysis

Diabetes mellitus is a multi-systematic chronic metabolic disorder and life-threatening disease resulting from impaired glucose homeostasis. The inhibition of glucosidase, particularly α-glucosidase, could serve as an effective methodology in treating diabetes. Attributed to the catalytic function of glucosidase, the present research focuses on the synthesis of sulfonamide-based acyl pyrazoles (5a-k) followed by their in vitro and in silico screening against α-glucosidase. The envisaged structures of prepared compounds were confirmed through NMR and FTIR spectroscopy and mass spectrometry. All compounds were found to be more potent against α-glucosidase than the standard drug, acarbose (IC50 = 35.1 ± 0.14 µM), with IC50 values ranging from 1.13 to 28.27 µM. However, compound 5a displayed the highest anti-diabetic activity (IC50 = 1.13 ± 0.06 µM). Furthermore, in silico studies revealed the intermolecular interactions of most potent compounds (5a and 5b), with active site residues reflecting the importance of pyrazole and sulfonamide moieties. This interaction pattern clearly manifests various structure-activity relationships, while the docking results correspond to the IC50 values of tested compounds. Hence, recent investigation reveals the medicinal significance of sulfonamide-clubbed pyrazole derivatives as prospective therapeutic candidates for treating type 2 diabetes mellitus (T2DM).

The Contribution of Type 2 Diabetes to Parkinson's Disease Aetiology

Type 2 diabetes (T2D) and Parkinson's disease (PD) are chronic disorders that have a significant health impact on a global scale. Epidemiological, preclinical, and clinical research underpins the assumption that insulin resistance and chronic inflammation contribute to the overlapping aetiologies of T2D and PD. This narrative review summarises the recent evidence on the contribution of T2D to the initiation and progression of PD brain pathology. It also briefly discusses the rationale and potential of alternative pharmacological interventions for PD treatment.

The analgesic effects of insulin and its disorders in streptozotocin-induced short-term diabetes

Evidence suggests that insulin resistance plays an important role in developing diabetes complications. The association between insulin resistance and pain perception is less well understood. This study aimed to investigate the effects of peripheral insulin deficiency on pain pathways in the brain. Diabetes was induced in 60 male rats with streptozotocin (STZ). Insulin was injected into the left ventricle of the brain by intracerebroventricular (ICV) injection, then pain was induced by subcutaneous injection of 2.5% formalin. Samples were collected at 4 weeks after STZ injection. Dopamine (DA), serotonin, reactive oxygen species (ROS), and mitochondrial glutathione (mGSH) were measured by ELISA, and gene factors were assessed by RT-qPCR. In diabetic rats, the levels of DA, serotonin, and mGSH decreased in the nuclei of the thalamus, raphe magnus, and periaqueductal gray, and the levels of ROS increased. In addition, the levels of expression of the neuron-specific enolase and receptor for advanced glycation end genes increased, but the expression of glial fibrillary acidic protein expression was reduced. These results support the findings that insulin has an analgesic effect in non-diabetic rats, as demonstrated by the formalin test. ICV injection of insulin reduces pain sensation, but this was not observed in diabetic rats, which may be due to cell damage ameliorated by insulin.

Celecoxib ameliorates diabetic sarcopenia by inhibiting inflammation, stress response, mitochondrial dysfunction, and subsequent activation of the protein degradation systems

Aim: Diabetic sarcopenia leads to disability and seriously affects the quality of life. Currently, there are no effective therapeutic strategies for diabetic sarcopenia. Our previous studies have shown that inflammation plays a critical role in skeletal muscle atrophy. Interestingly, the connection between chronic inflammation and diabetic complications has been revealed. However, the effects of non-steroidal anti-inflammatory drug celecoxib on diabetic sarcopenia remains unclear. Materials and Methods: The streptozotocin (streptozotocin)-induced diabetic sarcopenia model was established. Rotarod test and grip strength test were used to assess skeletal muscle function. Hematoxylin and eosin and immunofluorescence staining were performed to evaluate inflammatory infiltration and the morphology of motor endplates in skeletal muscles. Succinate dehydrogenase (SDH) staining was used to determine the number of succinate dehydrogenase-positive muscle fibers. Dihydroethidium staining was performed to assess the levels of reactive oxygen species (ROS). Western blot was used to measure the levels of proteins involved in inflammation, oxidative stress, endoplasmic reticulum stress, ubiquitination, and autophagic-lysosomal pathway. Transmission electron microscopy was used to evaluate mitophagy. Results: Celecoxib significantly ameliorated skeletal muscle atrophy, improving skeletal muscle function and preserving motor endplates in diabetic mice. Celecoxib also decreased infiltration of inflammatory cell, reduced the levels of IL-6 and TNF-α, and suppressed the activation of NF-κB, Stat3, and NLRP3 inflammasome pathways in diabetic skeletal muscles. Celecoxib decreased reactive oxygen species levels, downregulated the levels of Nox2 and Nox4, upregulated the levels of GPX1 and Nrf2, and further suppressed endoplasmic reticulum stress by inhibiting the activation of the Perk-EIF-2α-ATF4-Chop in diabetic skeletal muscles. Celecoxib also inhibited the levels of Foxo3a, Fbx32 and MuRF1 in the ubiquitin-proteasome system, as well as the levels of BNIP3, Beclin1, ATG7, and LC3Ⅱ in the autophagic-lysosomal system, and celecoxib protected mitochondria and promoted mitochondrial biogenesis by elevating the levels of SIRT1 and PGC1-α, increased the number of SDH-positive fibers in diabetic skeletal muscles. Conclusion: Celecoxib improved diabetic sarcopenia by inhibiting inflammation, oxidative stress, endoplasmic reticulum stress, and protecting mitochondria, and subsequently suppressing proteolytic systems. Our study provides evidences for the molecular mechanism and treatment of diabetic sarcopenia, and broaden the way for the new use of celecoxib in diabetic sarcopenia.

The causal effect of HbA1c on white matter brain aging by two-sample Mendelian randomization analysis

Background

Poor glycemic control with elevated levels of hemoglobin A1c (HbA1c) is associated with increased risk of cognitive impairment, with potentially varying effects between sexes. However, the causal impact of poor glycemic control on white matter brain aging in men and women is uncertain.

Methods

We used two nonoverlapping data sets from UK Biobank cohort: gene-outcome group (with neuroimaging data, (N = 15,193; males/females: 7,101/8,092)) and gene-exposure group (without neuroimaging data, (N = 279,011; males/females: 122,638/156,373)). HbA1c was considered the exposure and adjusted "brain age gap" (BAG) was calculated on fractional anisotropy (FA) obtained from brain imaging as the outcome, thereby representing the difference between predicted and chronological age. The causal effects of HbA1c on adjusted BAG were studied using the generalized inverse variance weighted (gen-IVW) and other sensitivity analysis methods, including Mendelian randomization (MR)-weighted median, MR-pleiotropy residual sum and outlier, MR-using mixture models, and leave-one-out analysis.

Results

We found that for every 6.75 mmol/mol increase in HbA1c, there was an increase of 0.49 (95% CI = 0.24, 0.74; p-value = 1.30 × 10-4) years in adjusted BAG. Subgroup analyses by sex and age revealed significant causal effects of HbA1c on adjusted BAG, specifically among men aged 60-73 (p-value = 2.37 × 10-8).

Conclusion

Poor glycemic control has a significant causal effect on brain aging, and is most pronounced among older men aged 60-73 years, which provides insights between glycemic control and the susceptibility to age-related neurodegenerative diseases.

Heterogeneity and synaptic plasticity analysis of hippocampus based on db-/- mice induced diabetic encephalopathy

Chronic hyperglycemia can cause changes in synaptic plasticity of hippocampal cells, which has accelerated the pathological process of cognitive dysfunction. However, the heterogeneity of the hippocampal cell populations under long term high glucose statement remains largely unknown. To mimic chronic hyperglycemia induced cognitive function deficit in vivo, db-/- diabetic mice was selected and Novel Object Recognition(NOR) behavior tests were performed. Based on diabetic induced cognitive impairment(CI) animal model, single-cell RNA sequencing was performed in the hippocampus of CI group (21,379 cells) or control group (20,045 cells), and single cell RNA sequencing was applied, and then the single cell atlas of gene expression was profiled. The comprehensive analysis explicated 18 nerve cell clusters, including 9 distinct sub-clusters, More in-depth analysis of oligodendrocyte precursor cells(OPCs) showed five distinct OPCs sub-clusters including expressing marker gene Lingo2-OPCs, Kcnc1-OPCs, Sst-OPCs, Slc6a1-OPCs and Lhfpl3-OPCs, which seems to be able to proliferate, migrate, and finally differentiate into mature oligodendrocytes and produce myelin. To be noted, differentially expressed genes(DEGs) of the Sst-OPCs sub-cluster indicated that the genes participating in neuroactive ligand-receptor interaction, nervous system development and inflammatory process were up-regulated in diabetic induced cognitive impairment(DCI) groups compared to normal control groups. Integrating the data of neuroplasticity regulation, the 20th top-enriched biological process was associated with neuroplasticity regulation in CI groups compared to control groups. Among these neuroplasticity-related genes, the intersectional gene Sstr2 may play an important role in neuroplasticity regulation. Focused on neuroplasticity regulation and its related specific genes may provide potential new clues for the treatment of diabetes mellitus complicated with cognitive impairment. In summary, we showed the comprehensively transcriptional landscape of hippocampal cells in the db-/- diabetic mice with cognitive dysfunction, distinctive cell sub-clusters and the gene expression characteristics were identified, and also their special functions were proposed, which may give new clues and potential targets for diagnosis and treatment of diabetic encephalopathy.

Influence of BPPV and Meniere's Disease on Cognitive Abilities: A Questionnaire-Based Study

The vestibular system connects the inner ear to the midbrain and subcortical structures and can affect cognition. Patients with vertigo often experience cognitive symptoms such as attention deficits, memory problems, and spatial perception difficulties. This study aimed to explore the cognitive impairments associated with Benign paroxysmal positional vertigo (BPPV) and Meniere's Disease (MD). A non-experimental group comparison design was used with 107 participants divided into three groups: Group I (clinically normal), Group II (BPPV), and Group III (MD). Participants completed a questionnaire with 10 cognition-related questions, and their responses were scored. The data were found to be non-normally distributed. The analysis revealed a significant difference in scores between Group I and both Group II and Group III. Chi-square tests showed that the responses to cognition-related questions varied among the groups, with Group II exhibiting more cognitive problems. Associated conditions like hypertension, diabetes, and hearing loss did not significantly influence the responses within each group. This study suggests a significant relationship between cognitive problems and patients with BPPV and MD. However, there was no association found between the cognitive problems experienced in BPPV and MD patients. These findings align with previous research indicating that vestibular disorders can lead to deficits in spatial memory, attention, and other cognitive functions. By understanding the link between cognition and vestibular disorders, we can improve diagnosis and rehabilitation services to enhance the quality of life for these patients.

In Vivo and in Silico Based Evaluation of Antidiabetic Potential of an Isolated Flavonoid from Allium hookeri in Type 2 Diabetic Rat Model

Allium hookeri (F: Liliaceae), an indigenous plant of Manipur, India, is traditionally used to treat various diseases and disorders like diabetes, hypertension, and stomach ache. In our previous study, the methanol extract of the plant showed significant antidiabetic potential in rats. In the present study, we evaluated the antidiabetic potential of a flavonoid compound named MEA isolated from the methanolic leaf extract of A. Hookeri in rats. Additionally, we assessed the compound's mode of action through the molecular docking study. The MEA reduced the blood glucose level from 317±12.8 to 99.4±6.67 mg/dl after 21 days of treatment. Besides, MEA also restored the body weights and other biochemical parameters including lipid profile significantly compared to the diabetic group (p<0.001). The histoarchitecture of the pancreatic tissues of the MEA treated group was also improved compared to the diabetic group. In the docking study, the compound showed good binding affinity in the active binding site of the two structures of pancreatic beta-cell SUR1 (Sulfonylurea Receptor 1) subunit with CDocker energy -31.556 kcal/mol and -39.703 kcal/mol, respectively. The compound MEA was found to be drug-like with non-carcinogenic, non-mutagenic and non-irritant properties. These findings indicate the antidiabetic potential of MEA, which might act by modulating the pancreatic beta-cell SUR1 subunit present in the KATP channel. Hence, the MEA would be a promising lead molecule to develop new antidiabetic drug candidates of the future.

Metformin: The Winding Path from Understanding Its Molecular Mechanisms to Proving Therapeutic Benefits in Neurodegenerative Disorders

Metformin, a widely prescribed medication for type 2 diabetes, has garnered increasing attention for its potential neuroprotective properties due to the growing demand for treatments for Alzheimer's, Parkinson's, and motor neuron diseases. This review synthesizes experimental and clinical studies on metformin's mechanisms of action and potential therapeutic benefits for neurodegenerative disorders. A comprehensive search of electronic databases, including PubMed, MEDLINE, Embase, and Cochrane library, focused on key phrases such as "metformin", "neuroprotection", and "neurodegenerative diseases", with data up to September 2023. Recent research on metformin's glucoregulatory mechanisms reveals new molecular targets, including the activation of the LKB1-AMPK signaling pathway, which is crucial for chronic administration of metformin. The pleiotropic impact may involve other stress kinases that are acutely activated. The precise role of respiratory chain complexes (I and IV), of the mitochondrial targets, or of the lysosomes in metformin effects remains to be established by further research. Research on extrahepatic targets like the gut and microbiota, as well as its antioxidant and immunomodulatory properties, is crucial for understanding neurodegenerative disorders. Experimental data on animal models shows promising results, but clinical studies are inconclusive. Understanding the molecular targets and mechanisms of its effects could help design clinical trials to explore and, hopefully, prove its therapeutic effects in neurodegenerative conditions.

Host-parasite relationship modulates the effect of African mistletoe leaves on the cholinergic, monoaminergic and carbohydrate hydrolyzing enzymes in fruit fly

OBJECTIVES

Mistletoe infests common plant trees of great medicinal values such as Moringa and Almond. According to folklore, mistletoe leaves have been found to have application as food and medicine in the alleviation of various degenerative diseases. Host-parasite relationship may possibly influence the phytochemical and biological activities of mistletoe leaves. Hence, we examined the polyphenol contents, antioxidant properties, α-amylase, α-glucosidase, acetylcholinesterase (AChE) and monoamine oxidase (MAO) inhibitory activities of African mistletoe leaves obtained from Moringa and Almond host plants in fruit fly in vitro.

METHODS

The phenolic constituents of the leaves were evaluated using HPLC system. The antioxidant activities were determined through the ABTS, DPPH and OH free radicals scavenging properties, ferric (Fe3+) and malondialdehyde (MDA) reducing abilities and Fe2+ chelation. The inhibitory effects of the leaves aqueous extracts on α-amylase, α-glucosidase, AChE and MAO activities were also assessed.

RESULTS

The HPLC characterization of the leaves revealed that host plants caused marked variation in their phenolic composition, however, Almond mistletoe leaves had significantly (p<0.05) greater amounts of phenolic constituents. Both Moringa and Almond mistletoe leaves reduced Fe3+ and MDA levels, scavenged free radicals, chelated Fe2+ and inhibited α-amylase, α-glucosidase, AChE and MAO activities with the Almond mistletoe leaves having significantly (p<0.05) higher antioxidant properties and enzyme inhibitory activities.

CONCLUSIONS

This present study indicated that host plants could positively modulate the phenolic profile of mistletoe leaves and this probably brought about the vivid noticeable changes in their antioxidant abilities, cholinergic, monoaminergic and carbohydrate hydrolyzing enzymes inhibitory activities.

Potential Role of Glucagon-like Peptide-1 Receptor Agonists in the Treatment of Cognitive Decline and Dementia in Diabetes Mellitus

Dementia is a permanent illness characterized by mental instability, memory loss, and cognitive decline. Many studies have demonstrated an association between diabetes and cognitive dysfunction that proceeds in three steps, namely, diabetes-associated cognitive decrements, mild cognitive impairment (MCI; both non-amnesic MCI and amnesic MCI), and dementia [both vascular dementia and Alzheimer's disease (AD)]. Based on this association, this disease has been designated as type 3 diabetes mellitus. The underlying mechanisms comprise insulin resistance, inflammation, lipid abnormalities, oxidative stress, mitochondrial dysfunction, glycated end-products and autophagy. Moreover, insulin and insulin-like growth factor-1 (IGF-1) have been demonstrated to be involved. Insulin in the brain has a neuroprotective role that alters cognitive skills and alteration of insulin signaling determines beta-amyloid (Aβ) accumulation, in turn promoting brain insulin resistance. In this complex mechanism, other triggers include hyperglycemia-induced overproduction of reactive oxygen species (ROS) and inflammatory cytokines, which result in neuroinflammation, suggesting that antidiabetic drugs may be potential treatments to protect against AD. Among these, glucagon-like peptide-1 receptor agonists (GLP-1RAs) are the most attractive antidiabetic drugs due to their actions on synaptic plasticity, cognition and cell survival. The present review summarizes the significant data concerning the underlying pathophysiological and pharmacological mechanisms between diabetes and dementia.

The Aqueous Extract of Sclerocarya birrea, Nauclea latifolia, and Piper longum Mixture Protects Striatal Neurons and Movement-Associated Functionalities in a Rat Model of Diabetes-Induced Locomotion Dysfunction

Among the many complications of type 2 diabetes (T2D), locomotor disorders have been poorly studied and understood. Therefore, no disease-modifying treatment is usually considered. The study aimed to investigate the effect of the aqueous extract of Sclerocarya birrea, Nauclea latifolia, and Piper longum (SNP) mixture on locomotor activity in fructose/streptozotocin-induced diabetic rats. T2D was induced by 10% fructose orally (6 weeks) and streptozotocin (STZ, 35 mg/kg, i.v.) in 25 male rats. Diabetic animals received distilled water, metformin (200 mg/kg), or the aqueous extract of the SNP mixture (75, 150, or 300 mg/kg). A 10-minute open field test was performed in diabetic rats (glycemia: 126 and 350 mg/dL) to assess locomotor activity before and after treatment. A group of 5 normal rats (NC) served as controls throughout the study. Rats were sacrificed, and the striatum was removed for biochemical and histological studies. In untreated diabetic rats, fructose/STZ administration resulted in hyperglycemia that altered locomotor function as characterized by increased freezing time, decreased mobility time, number of lines crossed, and total travel time compared to NC. MDA, TNF-α, INF-γ, and nitrite levels were elevated in the striatum of diabetic rats, while catalase activity and GSH levels were decreased, indicating oxidative stress and neuroinflammatory changes. In untreated diabetic rats, the microstructure of the HE-stained striatum revealed lipid vacuolation (hydropic degeneration) of the parenchyma, indicating a loss of neuronal integrity. The locomotor dysfunction was significantly improved by the aqueous extract of the SNP mixture, both biochemically and histologically. As a result, our findings support the mixture's ability to correct diabetes-related locomotion disorders as a glucose-lowering product and antioxidant, anti-inflammatory, and neuroprotective agent. These results justify the use of the aqueous extract of a combination of these three plants to manage diabetes and neuroinflammatory complications in Northern Cameroon.

Diabetes, Edentulism, and Cognitive Decline: A 12-Year Prospective Analysis

Diabetes mellitus (DM) is a recognized risk factor for dementia, and increasing evidence shows that tooth loss is associated with cognitive impairment and dementia. However, the effect of the co-occurrence of DM and edentulism on cognitive decline is understudied. This 12-y cohort study aimed to assess the effect of the co-occurrence of DM and edentulism on cognitive decline and examine whether the effect differs by age group. Data were drawn from the 2006 to 2018 Health and Retirement Study. The study sample included 5,440 older adults aged 65 to 74 y, 3,300 aged 75 to 84 y, and 1,208 aged 85 y or older. Linear mixed-effect regression was employed to model the rates of cognitive decline stratified by age cohorts. Compared with their counterparts with neither DM nor edentulism at baseline, older adults aged 65 to 74 y (β = -1.12; 95% confidence interval [CI], -1.56 to -0.65; P < 0.001) and those aged 75 to 84 y with both conditions (β = -1.35; 95% CI, -2.09 to -0.61; P < 0.001) had a worse cognitive function. For the rate of cognitive decline, compared to those with neither condition from the same age cohort, older adults aged 65 to 74 y with both conditions declined at a higher rate (β = -0.15; 95% CI, -0.20 to -0.10; P < 0.001). Having DM alone led to an accelerated cognitive decline in older adults aged 65 to 74 y (β = -0.09; 95% CI, -0.13 to -0.05; P < 0.001); having edentulism alone led to an accelerated decline in older adults aged 65 to 74 y (β = -0.13; 95% CI, -0.17 to -0.08; P < 0.001) and older adults aged 75 to 84 (β = -0.10; 95% CI, -0.17 to -0.03; P < 0.01). Our study finds the co-occurrence of DM and edentulism led to a worse cognitive function and a faster cognitive decline in older adults aged 65 to 74 y.

Association of Life's Simple 7 with mild cognitive impairment in community-dwelling older adults in China: a cross-sectional study

Background

Life's Simple 7 (LS7), a metric composed of seven intervenable cardiovascular risk factors, is initiated by the American Heart Association to improve cardiovascular health. The components of LS7 have been reported as risk factors for dementia. However, few studies investigated the association between LS7 metric and mild cognitive impairment (MCI).

Methods

The study was carried out in a primary care facility between 8 June and 10 July 2022. A total of 297 community-dwelling residents aged 65 years or older were recruited. Sociodemographic, comorbidity, and lifestyle characteristics were collected through the questionnaires, and biological parameters were obtained from blood sample examinations. Logistic regression was used to analyze the association between LS7 scores (overall, behavioral, and biological) and individual components with MCI, adjusting sex, age, education, and cardiovascular disease (CVD).

Results

In comparison with the cognitively intact group (n = 195), the MCI group (n = 102) had a lower education level and a higher proportion of hypertension. Multivariate logistic regression analysis, adjusting sex, age, education, and CVD demonstrated a significant association between MCI and overall LS7 score [odd ratio = 0.805, 95% confidence interval (0.690, 0.939)] and biological score [odd ratio = 0.762, 95% confidence interval (0.602, 0.965)].

Conclusion

Life's Simple 7 was associated with MCI in community-dwelling older adults, indicating that LS7 could be used as guidance in the prevention of dementia in the community.

Voxel-based morphometry reveals the correlation between gray matter volume and serum P-tau-181 in type 2 diabetes mellitus patients with different HbA1c levels

Introduction

Emerging evidence suggested widespread decreased gray matter volume (GMV) and tau hyperphosphorylation were associated with type 2 diabetes mellitus (T2DM). Insulin resistance is one of the mechanisms of neuron degeneration in T2DM; it can decrease the activity of protein kinase B and increase the activity of glycogen synthesis kinase-3β, thus promoting the hyperphosphorylation of tau protein and finally leading to neuronal degeneration. However, the association between GMV and serum tau protein phosphorylated at threonine 181 (P-tau-181) in T2DM patients lacks neuroimaging evidence. We aimed to investigate the difference in brain GMV between T2DM patients with different glycated hemoglobin A1c (HbA1c) levels and healthy control (HC) subjects and the correlation between serum P-tau-181 and GMV in T2DM patients.

Methods

Clinical parameters, biochemical indicators, and MRI data were collected for 41 T2DM patients with high glycosylated hemoglobin level (HGL), 17 T2DM patients with normal glycosylated hemoglobin level (NGL), and 42 HC subjects. Voxel-based morphometry (VBM) method was applied to investigate GMV differences among groups, and multiple regression analysis was used to examine the correlation between serum P-tau-181 and GMV.

Results

Compared with HC subjects, the T2DM patients with HGL or NGL all showed significantly decreased GMV. Briefly, the GMV decreased in T2DM patients with HGL was mainly in the bilateral parahippocampal gyrus (PHG), right middle temporal gyrus (MTG), temporal pole (TPOmid), hippocampus (HIP), and left lingual gyrus. The GMV reduction in T2DM patients with NGL was in the right superior temporal gyrus (STG), and there was no significant difference in GMV between the two diabetic groups. The GMV values of bilateral PHG, right MTG, TPOmid, HIP, and STG can significantly (p < 0.0001) distinguish T2DM patients from HC subjects in ROC curve analysis. In addition, we found that serum P-tau-181 levels were positively correlated with GMV in the right superior and middle occipital gyrus and cuneus, and negatively correlated with GMV in the right inferior temporal gyrus in T2DM patients.

Conclusion

Our study shows that GMV atrophy can be used as a potential biological indicator of T2DM and also emphasizes the important role of P-tau-181 in diabetic brain injury, providing new insights into the neuropathological mechanism of diabetic encephalopathy.

Effects of diabetes mellitus on step length and minimum toe clearance adaptation

BACKGROUND

Adaptive gait involves the ability to adjust the leading foot in response to the requirement of dynamic environments during walking. Accurate adjustments of the minimum toe clearance (MTC) height and step length can prevent older people from falling when walking and responding to hazards. Although older people with diabetes fall more frequently than healthy older adults, no previous studies have quantified their adaptive gait abilities. This study aimed to investigate the effects of diabetes mellitus on step length and MTC height adjustments using a non-immersive virtual-reality system.

METHODS

Sixteen young adults (26 ± 5 years, 7 females), 16 healthy older adults (68 ± 5 years, 6 females), and 16 older adults with diabetes (70 ± 5 years, 6 females) completed adaptability tests while walking on a treadmill. A computer system visualised a continuous real-time signal of absolute step length and MTC on a monitor. Each person responded to four discrete participant-specific step length and MTC visual targets that were presented on the same signal. Tasks were to match the peaks of interest on each signal to presented targets. Targets were 10% longer or shorter than the mean baseline step length, and 2.5 cm, and 3.5 cm higher than the mean baseline MTC. When a target was displayed, it remained unchanged for 10 consecutive foot displacement adaptation attempts. Then, the target was removed and a new target or the same target was present after 10 consecutive steps and remained for 10 steps. Each target was randomly presented three times (3 × 10). Step length and MTC height adjustments in response to targets were measured and compared among groups.

RESULTS

Mean preferred walking speeds were not different among groups significantly when no targets were presented on the monitor in baseline walking. However, when participants walked on a treadmill while attempting to match step lengths or MTC heights to displayed targets on the monitor, the group with diabetes had reduced step length and MTC adjustments compared with other groups significantly. They showed greater errors (differences between their step lengths/MTC heights and presented targets) on the monitor.

CONCLUSIONS

This study quantified reduced abilities for older individuals with diabetes to adjust both step length and MTC in response to stimuli compared to healthy older counterparts. Reduced step length and MTC height adjustments can increase falls in at risk populations. The presented virtual-reality system has merits for assessing and training step and MTC adaptation.

Lipin2 ameliorates diabetic encephalopathy via suppressing JNK/ERK-mediated NLRP3 inflammasome overactivation

OBJECTIVES

Diabetic encephalopathy (DE) is a common complication of diabetes in the central nervous system, which can cause cognitive dysfunction in patients. However, its pathophysiological mechanism has not been elucidated, and thus effective prevention and treatment methods are still lacking.Previous studies reported that neuroinflammation involved in the central neuropathy, while lipin2 plays an important role in inflammatory response.Therefore, we aimed to investigate the effects of lipin2 on regulating inflammatory response in the pathogenesis of DE.

METHODS

BV2 cells were treated with high glucose and infected with lipin2 overexpression or knockdown virus to observe the cell viability. Then, we constructed a mouse model of DE, and constructed a lipin2 knockdown or overexpression model by injecting lentivirus into the brain with stereotaxis. The expression of lipin2 in inflammatory bodies and related inflammatory factor signaling pathway-related proteins were examined by western blot and quantitative real-time PCR. Morris water maze was used to evaluate the spatial learning and memory of mice.

RESULTS

High glucose decreased the expression of lipin2 in BV2 cells, while overexpression of lipin2 in BV2 cells significantly suppressed the inflammatory response and apoptosis induced by high glucose. Meanwhile, the expression of lipin2 was down-regulated in the hippocampus in a DE mice model. Up-regulation of lipin2 in the hippocampus of DE mice inhibited JNK/ERK signaling pathway, reduced NLRP3 inflammasome-mediated inflammatory response, down-regulated IL-1/TNF-α expression, and improved synaptic plasticity and cognitive dysfunction in mice. Conversely, knockdown of lipin2 increased NLRP3 inflammasome overactivation, caused neuronal abnormalities and cognitive impairment in mice.

CONCLUSIONS

Lipin2 may play a neuroprotective role in DE by inhibiting JNK/ERK-mediated NLRP3 inflammasome overactivation and subsequent inflammatory responses. It may be a potential therapeutic target for DE therapy.

Investigating the effects of Citrullus colocynthis on cognitive performance and anxiety-like behaviors in STZ-induced diabetic rats

Background: Diabetes can impair cognitive performance and lead to dementia. Patients with type 1 diabetes mellitus (T1DM) are reported with different levels of cognitive dysfunctions in various cognitive domains ranging from general intellectual testing to specific deficits with visuospatial abilities, motor speed, writing, attention, reading, and psychomotor efficiency. The present study aimed to investigate the effect of Citrullus colocynthis on cognitive functions.Methods: A total of 42 male Wistar rats (3-4  months old and weighing 200-250  g) were tested in the current study. Rats were randomly allocated into 3 groups of control, Diabetes, and Diabetes + Drug. The diabetic rats received Citrullus colocynthis extraction orally. The behavioral tests included the open field, elevated plus maze (EPM), novel object recognition (NOR), passive avoidance tests, and Morris Water Maze (MWM) tests. Data were analyzed using student and paired t-tests via SPSS software version 16.Results: Our results showed the protective effects of Citrullus colocynthis administration against cognitive impairments. This is followed by STZ-induced diabetes in the MWM, novel object recognition, and passive avoidance tasks. Also, it was found that Citrullus colocynthis improved anxiety in diabetic rats.Conclusion According to the findings of this study, the administration of 200  mg/kg C. colocynthis once per day for 40  days can lead to ameliorated cognitive impairments and antidiabetic effects such as increasing body weight and decreasing FBS.

Association of hyperglycaemia and hyperlipidaemia with cognitive dysfunction in schizophrenia spectrum disorder

The objective of the study was to investigate the association of blood glucose and lipid profile parameters with cognitive impairment in schizophrenia. A total of 200 schizophrenia patients and 169 controls were enrolled in the study. Blood glucose and lipid profile were estimated in all the subjects. Cognition was assessed using Addenbrooke cognitive examination-III (ACE-III). Fasting glucose (p ≤ .001) and triacylglycerol (p = .018) were increased and HDL-Cholesterol (p ≤ .001), was reduced in schizophrenia. Glucose (r = -0.158, p = .026), total cholesterol (r = -0.249, p = .0001) and triacylglycerol (r = -0.168, p = .018) was negatively correlated with total ACE III score. Triacylglycerol (p = .041) was elevated in cases with mild cognitive impairment. Plasma glucose, total cholesterol and triacylglycerol were associated with various cognitive domains suggesting that hyperglycaemia and hyperlipidaemia might increase the risk of cognitive impairment in schizophrenia.

Gut microbiota composition is altered in a preclinical model of type 1 diabetes mellitus: Influence on gut steroids, permeability, and cognitive abilities

Sex steroid hormones are not only synthesized from the gonads but also by other tissues, such as the brain (i.e., neurosteroids) and colon (i.e., gut steroids). Gut microbiota can be shaped from sex steroid hormones synthesized from the gonads and locally interacts with gut steroids as in turn modulates neurosteroids. Type 1 diabetes mellitus (T1DM) is characterized by dysbiosis and also by diabetic encephalopathy. However, the interactions of players of gut-brain axis, such as gut steroids, gut permeability markers and microbiota, have been poorly explored in this pathology and, particularly in females. On this basis, we have explored, in streptozotocin (STZ)-induced adult female rats, whether one month of T1DM may alter (I) gut microbiome composition and diversity by 16S next-generation sequencing, (II) gut steroid levels by liquid chromatography-tandem mass spectrometry, (III) gut permeability markers by gene expression analysis, (IV) cognitive behavior by the novel object recognition (NOR) test and whether correlations among these aspects may occur. Results obtained reveal that T1DM alters gut β-, but not α-diversity. The pathology is also associated with a decrease and an increase in colonic pregnenolone and allopregnanolone levels, respectively. Additionally, diabetes alters gut permeability and worsens cognitive behavior. Finally, we reported a significant correlation of pregnenolone with Blautia, claudin-1 and the NOR index and of allopregnanolone with Parasutterella, Gammaproteobacteria and claudin-1. Altogether, these results suggest new putative roles of these two gut steroids related to cognitive deficit and dysbiosis in T1DM female experimental model. This article is part of the Special Issue on "Microbiome & the Brain: Mechanisms & Maladies".

Type 2 Diabetes and Parkinson's Disease: A Focused Review of Current Concepts

Highly reproducible epidemiological evidence shows that type 2 diabetes (T2D) increases the risk and rate of progression of Parkinson's disease (PD), and crucially, the repurposing of certain antidiabetic medications for the treatment of PD has shown early promise in clinical trials, suggesting that the effects of T2D on PD pathogenesis may be modifiable. The high prevalence of T2D means that a significant proportion of patients with PD may benefit from personalized antidiabetic treatment approaches that also confer neuroprotective benefits. Therefore, there is an immediate need to better understand the mechanistic relation between these conditions and the specific molecular pathways affected by T2D in the brain. Although there is considerable evidence that processes such as insulin signaling, mitochondrial function, autophagy, and inflammation are involved in the pathogenesis of both PD and T2D, the primary aim of this review is to highlight the evidence showing that T2D-associated dysregulation of these pathways occurs not only in the periphery but also in the brain and how this may facilitate neurodegeneration in PD. We also discuss the challenges involved in disentangling the complex relationship between T2D, insulin resistance, and PD, as well as important questions for further research. © 2022 International Parkinson and Movement Disorder Society.

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.

Obesity-Induced Brain Neuroinflammatory and Mitochondrial Changes

Obesity is defined as abnormal and excessive fat accumulation, and it is a risk factor for developing metabolic and neurodegenerative diseases and cognitive deficits. Obesity is caused by an imbalance in energy homeostasis resulting from increased caloric intake associated with a sedentary lifestyle. However, the entire physiopathology linking obesity with neurodegeneration and cognitive decline has not yet been elucidated. During the progression of obesity, adipose tissue undergoes immune, metabolic, and functional changes that induce chronic low-grade inflammation. It has been proposed that inflammatory processes may participate in both the peripheral disorders and brain disorders associated with obesity, including the development of cognitive deficits. In addition, mitochondrial dysfunction is related to inflammation and oxidative stress, causing cellular oxidative damage. Preclinical and clinical studies of obesity and metabolic disorders have demonstrated mitochondrial brain dysfunction. Since neuronal cells have a high energy demand and mitochondria play an important role in maintaining a constant energy supply, impairments in mitochondrial activity lead to neuronal damage and dysfunction and, consequently, to neurotoxicity. In this review, we highlight the effect of obesity and high-fat diet consumption on brain neuroinflammation and mitochondrial changes as a link between metabolic dysfunction and cognitive decline.

Acute Pancreatitis and the Risk of Dementia in Diabetes: A Nationwide Cohort Study Using Korean Healthcare Claims Database

BACKGROUND

Diabetes is a major risk factor for the development of dementia, which has been proven to be associated with systemic inflammation. Acute pancreatitis, also a local and systemic inflammatory disease, is the most common gastrointestinal disease requiring acute hospitalization.

OBJECTIVE

The effect of acute pancreatitis on dementia was investigated in type 2 diabetic patients.

METHODS

Data was collected from the Korean National Health Insurance Service. The study sample included type 2 diabetes patients who received general health examination from 2009 to 2012. Cox proportional hazard regression analysis was used to evaluate the association between acute pancreatitis and dementia with adjustment of confounders. Stratified subgroup analysis by age, sex, smoking, alcohol consumption, hypertension, dyslipidemia, and body mass index was conducted.

RESULTS

Among the 2,328,671 participants in total, 4,463 patients had a history of acute pancreatitis before the health examination. During a median follow-up of 8.1 (IQR, 6.7-9.0) years, 194,023 participants (8.3%) developed all-cause dementia. Previous history of acute pancreatitis was a significant risk factor for dementia after adjustment of confounding variables (HR 1.39 [95% CI 1.26-1.53]). In the subgroup analysis, patient characteristics such as age under 65 years, male, current smoker, and alcohol consumption were significant risk factors for dementia in patients with a history of acute pancreatitis.

CONCLUSION

The history of acute pancreatitis was associated with the development of dementia in patients with diabetes. Because the risk of dementia increases with alcohol consumption and smoking in diabetic patients with history of acute pancreatitis, abstinence from alcohol and smoking should be recommended.

ChemR23 signaling ameliorates cognitive impairments in diabetic mice via dampening oxidative stress and NLRP3 inflammasome activation

Diabetes mellitus is associated with cognitive impairment characterized by memory loss and cognitive inflexibility. Recent studies have revealed that ChemR23 is implicated in both diabetes mellitus and Alzheimer's disease. However, the impact of ChemR23 on diabetes-associated cognitive impairment remains elusive. In this study, we explored the longitudinal changes of ChemR23 expression and cognitive function in STZ-induced type 1 diabetic mice and leptin receptor knockout type 2 diabetic mice at different ages. We also treated diabetic mice with ChemR23 agonists RvE1 or chemerin-9 to explore whether ChemR23 activation could alleviate diabetes-associated cognitive impairment. The underlying mechanism was further investigated in diabetic mice with genetic deletion of ChemR23. The results showed that ChemR23 expression was decreased along with aging and the progression of diabetes, suggesting that abnormal ChemR23 signaling may be involved in diabetes-associated cognitive impairment. Administration of RvE1 or chemerin-9 ameliorated oxidative stress and inhibited NLRP3 inflammasome activation through Nrf2/TXNIP pathway, and ultimately alleviated cognitive impairment in diabetic mice. Depletion of ChemR23 in diabetic mice abolished the beneficial effects of RvE1 and chemerin-9, and exacerbated cognitive impairment via increasing oxidative stress and activating NLRP3 inflammasome. Collectively, our data highlight the crucial role of ChemR23 signaling in diabetes-associated cognitive impairment via regulating oxidative stress and NLRP3 inflammasome, and targeting ChemR23 may serve as a promising novel strategy for the treatment of diabetes-associated cognitive impairment.

Identification of a Hydroxygallic Acid Derivative, Zingibroside R1 and a Sterol Lipid as Potential Active Ingredients of Cuscuta chinensis Extract That Has Neuroprotective and Antioxidant Effects in Aged Caenorhabditis elegans

We examined the effects of the extracts from two traditional Chinese medicine plants, Cuscuta chinensis and Eucommia ulmoides, on the healthspan of the model organism Caenorhabditis elegans. C. chinensis increased the short-term memory and the mechanosensory response of aged C. elegans. Furthermore, both extracts improved the resistance towards oxidative stress, and decreased the intracellular level of reactive oxygen species. Chemical analyses of the extracts revealed the presence of several bioactive compounds such as chlorogenic acid, cinnamic acid, and quercetin. A fraction from the C. chinensis extract enriched in zingibroside R1 improved the lifespan, the survival after heat stress, and the locomotion in a manner similar to the full C. chinensis extract. Thus, zingibroside R1 could be (partly) responsible for the observed health benefits of C. chinensis. Furthermore, a hydroxygallic acid derivative and the sterol lipid 4-alpha-formyl-stigmasta-7,24(241)-dien-3-beta-ol are abundantly present in the C. chinensis extract and its most bioactive fraction, but hardly in E. ulmoides, making them good candidates to explain the overall healthspan benefits of C. chinensis compared to the specific positive effects on stress resistance by E. ulmoides. Our findings highlight the overall anti-aging effects of C. chinensis in C. elegans and provide first hints about the components responsible for these effects.

Metformin use is associated with a reduced risk of cognitive impairment in adults with diabetes mellitus: A systematic review and meta-analysis

Objective

Controversy exists regarding the impact of metformin and whether it prevents or promotes the incidence of cognitive dysfunction. This systematic review and meta-analysis were conducted to identify the effect of metformin therapy on cognitive function in patients with diabetes.

Methods

Electronic databases (PubMed, EMBASE, PsycINFO, the Cochrane Library, and Web of Science) were systematically searched by two investigators from the date of inception until March 1, 2022. The study followed PRISMA guidelines. Inclusion criteria were defined according to the PECOSmodel. Eligible studies investigated cognitive dysfunction in metformin users compared with non-users in adults with diabetes. Only observational study designs (such as cohort, cross-section, and case-control) were included.

Results

A systematic search identified 1,839 articles, of which 28 (17 cohort, 8 case-control, and 3 cross-sectional studies) were included in the meta-analysis. Metformin reduced the occurrence of cognitive impairment in patients with diabetes [unadjusted hazard ratio (HR) = 0.67, 95% CI: 0.62–0.73; adjusted hazard ratio (aHR) = 0.92, 95% CI: 0.85–0.99]. In addition, the use of metformin was associated with a decreased risk of dementia (HR = 0.64, 95% CI: 0.59–0.69; aHR = 0.90, 95% CI: 0.84–0.96), while a random-effects meta-analysis indicated no significant effect of metformin on the risk of Alzheimer's disease (AD) (HR = 0.85, 95% CI: 0.60–1.22; aHR = 1.10, 95% CI: 0.95–1.28).

Conclusion

Metformin therapy decreased the occurrence risk of cognitive decline in patients with diabetes mellitus. Moreover, the use of metformin by adults with diabetes for the prevention of dementia, but not AD, is supported by the available evidence.

Phenoxy pendant isatins as potent α-glucosidase inhibitors: reciprocal carbonyl⋯carbonyl interactions, antiparallel π⋯π stacking driven solid state self-assembly and biological evaluation

Carbonyl-carbonyl (CO⋯CO) interactions are recently explored noncovalent interactions of significant interest owing to their role in the stability of biomacromolecules. Currently, substantial efforts are being made to understand the nature of these interactions. In this study, twelve phenoxy pendant isatins 1-12 have been evaluated for their α-glucosidase inhibitory potential in addition to the analysis of X-ray single crystals of 4 and 9. Both compounds 4 and 9 showed intriguing and unique self-assembled structures. The CO⋯CO and antiparallel displaced π⋯π stacking interactions are mainly involved in the formation of 1D-stair like supramolecular chains of 4 whereas antiparallel π⋯π stacking interactions drive the formation of 1D-columnar stacks of 9. These compounds not only highlight the potential of the isatin moiety in forming strong CO⋯CO and antiparallel π⋯π stacking interactions but also are interesting models to provide considerable insight into the nature of these interactions. The in vitro biological studies revealed that all twelve phenoxy pendant isatins 1-12 are highly potent inhibitors of α-glucosidase enzyme with IC50 values ranging from 5.32 ± 0.17 to 150.13 ± 0.62 μM, showing many fold more potent activity than the standard drug, acarbose (IC50 = 873.34 ± 1.67). Easy access and high α-glucosidase inhibition potential of these phenoxy pendant isatins 1-12 provide an attractive platform for finding more effective medication for controlling postprandial hyperglycemia.

The attenuation effect of potassium 2-(1-hydroxypentyl)-benzoate in a mouse model of diabetes-associated cognitive decline: The protein expression in the brain

Aims

dl‐PHPB (potassium 2‐(1‐hydroxypentyl)‐benzoate) has been shown to have neuroprotective effects against acute cerebral ischemia, vascular dementia, and Alzheimer's disease. The aim of this study was to investigate the effects of dl‐PHPB on memory deficits and preliminarily explore the underlying molecular mechanism.

Methods

Blood glucose and behavioral performance were evaluated in the KK‐A^y diabetic mouse model before and after dl‐PHPB administration. Two‐dimensional difference gel electrophoresis (2D‐DIGE)‐based proteomics was used to identify differentially expressed proteins in brain tissue. Western blotting was used to study the molecular mechanism of the related signaling pathways.

Results

Three‐month‐old KK‐A^y mice were given 150 mg/kg dl‐PHPB by oral gavage for 2 months, which produced no effect on the level of serum glucose. In the Morris water maze test, KK‐A^y mice treated with dl‐PHPB showed significant improvements in spatial learning and memory deficits compared with vehicle‐treated KK‐A^y mice. Additionally, we performed 2D‐DIGE to compare brain proteomes of 5‐month KK‐A^y mice treated with and without dl‐PHPB. We found 14 altered proteins in the cortex and 11 in the hippocampus; two of the 25 altered proteins and another four proteins that were identified in a previous study on KK‐A^y mice were then validated by western blot to further confirm whether dl‐PHPB can reverse the expression levels of these proteins. The phosphoinositide 3‐kinase/protein kinase B/glycogen synthase kinase‐3β (PI3K/Akt/GSK‐3β) signaling pathway was also changed in KK‐A^y mice and dl‐PHPB treatment could reverse it.

Conclusions

These results indicate that dl‐PHPB may play a potential role in diabetes‐associated cognitive impairment through PI3K/Akt/GSK‐3β signaling pathway and the differentially expressed proteins may become putative therapeutic targets.

Peripheral versus central insulin and leptin resistance: Role in metabolic disorders, cognition, and neuropsychiatric diseases

Insulin and leptin are classically regarded as peptide hormones that play key roles in metabolism. In actuality, they serve several functions in both the periphery and central nervous system (CNS). Likewise, insulin and leptin resistance can occur both peripherally and centrally. Metabolic disorders such as diabetes and obesity share several key features including insulin and leptin resistance. While the peripheral effects of these disorders are well-known (i.e. cardiovascular disease, hypertension, stroke, dyslipidemia, etc.), the CNS complications of leptin and insulin resistance have come into sharper focus. Both preclinical and clinical findings have indicated that insulin and leptin resistance are associated with cognitive deficits and neuropsychiatric diseases such as depression. Importantly, these studies also suggest that these deficits in neuroplasticity can be reversed by restoration of insulin and leptin sensitivity. In view of these observations, this review will describe, in detail, the peripheral and central functions of insulin and leptin and explain the role of insulin and leptin resistance in various metabolic disorders, cognition, and neuropsychiatric diseases.

Involvement of Paired Immunoglobulin-like Receptor B in Diabetes-Associated Cognitive Dysfunction Through Modulation of Axon Outgrowth and Dendritic Remodeling

Type 2 diabetic patients have high risk of developing cognitive dysfunction, in which neural structural plasticity has played a pivotal role. Paired immunoglobulin-like receptor B (PirB), a receptor mainly expressed in neurons, acts as a critical inhibitor of neurite outgrowth and neural plasticity. However, the role of PirB in type 2 diabetes-associated cognitive dysfunction remains unknown. In this study, learning and memory impairment was observed in 24-week-old db/db mice by performing Morris water maze task, and the number of synapses along with the length of postsynaptic density by transmission electron microscopy were reduced in the hippocampus of db/db mice. Furthermore, PirB expression in the hippocampus of db/db mice was significantly upregulated using western blotting and immunofluorescence analysis. In cultured hippocampal neurons, high glucose treatment reduced the length of the longest neurite as well as axon initial segment (AIS), whereas silencing PirB expression rescued high glucose-induced neurite outgrowth inhibition, but not AIS. Additionally, cognitive deficits, dendrite morphology defects, and synapse-related proteins loss in db/db mice were alleviated when PirB knockdown was performed by adeno-associated virus injection. In conclusion, PirB is involved in diabetes-associated cognitive dysfunction through modulation of axon outgrowth and dendritic remodeling, providing a potential therapeutic target for diabetes-associated cognitive dysfunction.

Altered Structural and Functional MRI Connectivity in Type 2 Diabetes Mellitus Related Cognitive Impairment: A Review

Type 2 diabetes mellitus (T2DM) is associated with cognitive impairment in many domains. There are several pieces of evidence that changes in neuronal neuropathies and metabolism have been observed in T2DM. Structural and functional MRI shows that abnormal connections and synchronization occur in T2DM brain circuits and related networks. Neuroplasticity and energy metabolism appear to be principal effector systems, which may be related to amyloid beta (Aβ) deposition, although there is no unified explanation that includes the complex etiology of T2DM with cognitive impairment. Herein, we assume that cognitive impairment in diabetes may lead to abnormalities in neuroplasticity and energy metabolism in the brain, and those reflected to MRI structural connectivity and functional connectivity, respectively.

Fustin Inhibits Oxidative Free Radicals and Inflammatory Cytokines in Cerebral Cortex and Hippocampus and Protects Cognitive Impairment in Streptozotocin-Induced Diabetic Rats

The phytogenic flavanol component of the plant Rhus verniciflua Stokes is fustin which is implicated in various disease aliments and has promising therapeutic efficacy and a long history of its uses in the Indian medicinal system. The present study investigated the ameliorative effect of fustin in streptozotocin (STZ) induced cognitive impairments in the diabetic animal paradigm. A total of five different animal groups were used for the present study.The preclinical efficacy of fustin at 50 mg/kg and 100 mg/kg was studied in diabetic male rats by employing a 35-day study design. In the present investigation the Morris water maze test (MWM) and elevated plus maze (EPM) test were employed as behavioral paradigms for the assessment of memory impairments. The study design also carried out certain biochemical parameters which include glutathione (GSH), superoxide dismutase (SOD), catalase activity (CAT), malondialdehyde (MDA), nitric oxide (NO), relative interleukin-6 (IL-6), and IL-1B in samples obtained from cerebral cortex and hippocampus. The behavioral parameters with MWM and EPM were significant restored in fustin treatment groups as compared to elevated levels in the diabetic control group. Furthermore, fustin significantly improved the altered levels of several biochemical parameters for cognitive dysfunction such as GSH, SOD, CAT, MDA, NO, and relative IL-6 and IL-1B compared to a diabetic control group. The present investigation highlights certain preclinical pieces of evidence that strongly indicate that fustin might restore the normal cognitive function in the experimental animal paradigm.