Elevated Plasma Free Fatty Acid Susceptible to Early Cognitive Impairment in Type 2 Diabetes Mellitus

Exploring the effect and mechanism of action of Jinlida granules (JLD) in the treatment of diabetes-associated cognitive impairment based on network pharmacology with experimental validation

OBJECTIVES

To explore the effect and the probable mechanisms of JLD in the treatment of type 2 diabetes mellitus (T2DM) - associated cognitive impairment (TDACI).

METHODS

The effect of JLD in combating TDACI was assessed in T2DM model mice by conducting Morris water maze (MWM) behaviour testing. Active components and their putative targets, as well as TDACI-related targets, were collected from public databases. Protein-protein interactions (PPIs), Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses and molecular docking were then utilized to explore potential molecular network mechanisms. Finally, the main targets were verified in animal model experiments.

RESULTS

MWM test showed that JLD improved aspects of behaviour in T2DM model mice. JLD improved glucose intolerance, tissue insulin sensitivity, lipid metabolism and enhanced synapse-associated protein expression in hippocampus tissue. Network pharmacology revealed 185 active components, 337 targets of JLD, and 7998 TDACI related targets were obtained . PPI network analyses revealed 39 core targets. GO and KEGG analyses suggested that JLD might improve TDACI by regulating gene expression, apoptotic processes and inflammatory responses mainly via PI3K-AKT and AGE-RAGE signaling pathways. Molecular docking revealed strong binding of the main components to core targets. JLD reduced hippocampus tissue expression of the inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL6), core targets of treatment of TDACI.

CONCLUSIONS

The findings suggested that JLD has the potential to improve TDACI through multiple components, multiple targets and multiple pathways. JLD may be a promising treatment for diabetic cognitive impairment.

Sevoflurane anesthesia during late gestation induces cognitive disorder in rat offspring via the TLR4/BDNF/TrkB/CREB pathway

Sevoflurane (Sevo) is widely used for general anesthesia during pregnancy. Emerging evidence indicates that maternal Sevo exposure can trigger developmental neurotoxicity in the offspring. Nonetheless, the underlying mechanisms need further investigation. Pregnant Sprague-Dawley rats on gestational day 18 were exposed to 3.5% Sevo to induce the rat model of neurotoxicity. TAK-242, a TLR4 inhibitor, was administrated to inhibit the signaling transduction. Hippocampal tissues of rat offspring were harvested for immunohistochemical staining, TUNEL staining, Western blotting, ELISA, and measurement of oxidative stress-related markers. Serum samples were collected to evaluate lipid metabolism-associated factors. Morris water maze was implemented to test the cognitive function of offspring rats. Rat hippocampal neurons were isolated to elucidate the effect of TAK-242 on the BDNF/TrkB/CREB signaling in vitro. The results showed that maternal Sevo exposure during the third trimester induced neuroinflammation, lipid metabolism disturbance, and oxidative stress, and impaired the spatial learning and memory of rat offspring. Sevo upregulated TLR4 and impeded BDNF/TrkB/CREB signaling transduction in the hippocampus of rat offspring; TAK-242 administration reversed these effects. In conclusion, Sevo anesthesia during late gestation impairs the learning and memory ability of rat offspring possibly by promoting neuroinflammation and disturbing lipid metabolism via the TLR4/BDNF/TrkB/CREB pathway.

Interleukin-5: an indicator of mild cognitive impairment in patients with type 2 diabetes mellitus - a comprehensive investigation ranging from bioinformatics analysis to clinical research

PURPOSE

Neuroinflammation constitutes an underlying mechanism for cognitive impairment. Here, we endeavor to scrutinize the potential contribution of interleukin-5 (IL-5) towards mild cognitive impairment (MCI), and to assess its diagnostic value for MCI in patients with type 2 diabetes mellitus (T2DM).

METHODS

RNA-seq was used to explore the potential neuroinflammation factors in the hippocampus of diabetic mice with cognitive decline. Additionally, the promising risk factor was verified in animals. Finally, the association between IL-5 levels and cognitive function and its diagnostic value for MCI were assessed.

RESULTS

In animals, up-regulated IL-5 mRNA and protein levels were detected by RNA-seq and (or) verified experiments in the hippocampus of diabetic db/db mice with cognitive decline, compared to those of db/m mice without diabetes. In human, compared to diabetic patients without MCI, those with MCI demonstrate elevated levels of IL-5. It is natively associated with Montreal Cognitive Assessment (MoCA) scores, reflecting global cognitive function, and positively correlated with Trail Making Test A (TMTA) scores, reflecting information processing speed. Furthermore, an elevated level of IL-5 is identified as a risk factor for MCI, and a factor that influences TMTA scores. Finally, it is recommended that the cut-off value for IL-5 in the diagnosis of MCI is 22.98 pg/mL, with a sensitivity of 68.6% and specificity of 72.9%.

CONCLUSIONS

IL-5 is considered a risk factor for MCI in T2DM patients and is associated with their performance in information processing speed. Moreover, an elevated level of IL-5 is a plausible biomarker for MCI in T2DM patients.

Triglycerides and metabolic syndrome: from basic to mechanism - A narrative review

CONTENT

The impact of triglyceride levels is important to understand the changes in metabolism and structure. With an increase in obesity and hyperlipidemia due to diet; cardiovascular and neuronal structural changes have been shown to be more distinct.

OBJECTIVE

This review aims to discuss the pathophysiology and mechanisms involved in increased levels of triglycerides leading to vascular impairment, metabolic syndrome and cognitive decline.

METHODS

The literature search was performed using the PubMed, Google scholar and Scopus databases, among which 180 articles were shortlisted based on key words, abstract, materials and methods and results. Among these 74 articles have been cited for the review.

RESULTS AND DISCUSSION

The review discusses the impact of hypertriglyceridemia on metabolism, triglyceride storage, and neurovascular integrity, highlighting mechanisms contributing to vascular dysfunction, metabolic syndrome, and cognitive deterioration.

CONCLUSION

Elevated triglyceride levels are a key factor in altering metabolic pathways and structural integrity in cardiovascular and neuronal systems. This review provides insights into the mechanisms underlying metabolic disorders caused by elevated triglyceride levels, It highlights the need for further studies to provide more supportive evidence and address existing limitations in understanding these changes.

Association of the serum levels of saturated fatty acids and mild cognitive impairment: a cross-sectional study

OBJECTIVES

To investigate the association of serum saturated fatty acids (SFAs) and prevalent mild cognitive impairment (MCI) among middle-aged and elderly Chinese.

METHODS

A total of 607 Chinese adults aged at least 45 years were included in the baseline survey of The Lifestyle and Healthy Aging of Chinese Square Dancer Study. Serum concentrations of individual SFAs including 6 even-chain SFAs (C14:0, C16:0, C18:0, C20:0, C22:0, and C24:0) and 4 odd-chain SFAs (C15:0, C17:0, C21:0, and C23:0), were quantified by Gas chromatography system with a mass spectrometer. According to Petersen's criteria, prevalent MCI was diagnosed by neurologists through uniformed neuropsychological tests, including trail-making test-part B (TMT-B), auditory verbal learning test (AVLT), digit symbol substitution test (DSST), and verbal fluency test (VFT).

RESULTS

The median age was 62 years with an interquartile range of 57.0 to 67.0 years, and 86 (14.17%) participants were living with MCI. Higher levels of either even-chain or odd-chain individual SFAs were associated with the higher odds of MCI, and their odds ratios (ORs) and 95% confidence intervals (95%CIs) were 2.054 (1.012 to 4.171) for C14:0, 2.246 (1.061 to 4.755) for C16:0, 2.789 (1.321 to 5.886) for C18:0, and 2.329 (1.136 to 4.778) for C15:0, and 2.761 (1.310 to 5.820) for C17:0, respectively.

CONCLUSIONS

The serum concentration of SFAs was positively related to the odds of MCI in middle-aged and elderly adults. Determining the link between SFAs profiles and MCI may inform a better understanding of the potential role of saturated fat intake on cognitive function.

A mediation analysis of the role of total free fatty acids on pertinence of gut microbiota composition and cognitive function in late life depression

BACKGROUND

Extensive evidence demonstrates correlations among gut microbiota, lipid metabolism and cognitive function. However, there is still a lack of researches in the field of late-life depression (LLD). This research targeted at investigating the relationship among gut microbiota, lipid metabolism indexes, such as total free fatty acids (FFAs), and cognitive functions in LLD.

METHODS

Twenty-nine LLD patients from the Cognitive Outcome Cohort Study of Depression in Elderly were included. Cognitive functions were estimated through the Chinese version of Montreal Cognitive Assessment (MoCA). Blood samples were collected to evaluate serum lipid metabolism parameters. Fecal samples were evaluated for gut microbiota determination via 16S rRNA sequencing. Spearman correlation, linear regression and mediation analysis were utilized to explore relationship among gut microbiota, lipid metabolism and cognitive function in LLD patients.

RESULTS

Spearman correlation analysis revealed significant correlations among Akkermansia abundance, total Free Fatty Acids (FFAs) and MoCA scores (P < 0.05). Multiple regression indicated Akkermansia and total FFAs significantly predicted MoCA scores (P < 0.05). Mediation analysis demonstrated that the correlation between decreased Akkermansia relative abundance and cognitive decline in LLD patients was partially mediated by total FFAs (Bootstrap 95%CI: 0.023-0.557), accounting for 43.0% of the relative effect.

CONCLUSION

These findings suggested a significant relationship between cognitive functions in LLD and Akkermansia, as well as total FFAs. Total FFAs partially mediated the relationship between Akkermansia and cognitive functions. These results contributed to understanding the gut microbial-host lipid metabolism axis in the cognitive function of LLD.

Untargeted Metabolomic Profiling Reveals Differentially Expressed Serum Metabolites and Pathways in Type 2 Diabetes Patients with and without Cognitive Decline: A Cross-Sectional Study

Diabetes is recognized as a risk factor for cognitive decline, but the underlying mechanisms remain elusive. We aimed to identify the metabolic pathways altered in diabetes-associated cognitive decline (DACD) using untargeted metabolomics. We conducted liquid chromatography-mass spectrometry-based untargeted metabolomics to profile serum metabolite levels in 100 patients with type 2 diabetes (T2D) (54 without and 46 with DACD). Multivariate statistical tools were used to identify the differentially expressed metabolites (DEMs), and enrichment and pathways analyses were used to identify the signaling pathways associated with the DEMs. The receiver operating characteristic (ROC) analysis was employed to assess the diagnostic accuracy of a set of metabolites. We identified twenty DEMs, seven up- and thirteen downregulated in the DACD vs. DM group. Chemometric analysis revealed distinct clustering between the two groups. Metabolite set enrichment analysis found significant enrichment in various metabolite sets, including galactose metabolism, arginine and unsaturated fatty acid biosynthesis, citrate cycle, fructose and mannose, alanine, aspartate, and glutamate metabolism. Pathway analysis identified six significantly altered pathways, including arginine and unsaturated fatty acid biosynthesis, and the metabolism of the citrate cycle, alanine, aspartate, glutamate, a-linolenic acid, and glycerophospholipids. Classifier models with AUC-ROC > 90% were developed using individual metabolites or a combination of individual metabolites and metabolite ratios. Our study provides evidence of perturbations in multiple metabolic pathways in patients with DACD. The distinct DEMs identified in this study hold promise as diagnostic biomarkers for DACD patients.

Comparison of the relationship between cognitive function and future falls in Chinese community-dwelling older adults with and without diabetes mellitus

OBJECTIVE

The aim of this study was to determine whether cognitive function is associated with future falls in older patients with diabetes mellitus (DM) compared with those without DM. Cognitive function was divided into several domains to further analyze.

METHODS

A total of 678 individuals met the inclusion criteria and comprised the final study population. The mean age was 74.35 ± 5.35 years, and 58.9% of the participants were female (n = 400). At the baseline, cognitive function was measured by the Mini Mental State Examination (MMSE), and DM diagnoses were determined by medical records. The self-reported any falls data were obtained via face-to-face questioning at the 1-year follow-up.

RESULTS

At baseline, 15.6% of participants (n = 106) were diagnosed with DM. According to whether they had any falls during 1-year follow-up, there was a significant difference between the two group in fasting plasma glucose (p = 0.012) and DM (p = 0.036) at baseline. Among the older adults with DM, those who had experienced any falls had poorer cognitive function (p = 0.014). After adjusting for various covariates, we found that MMSE (95% CI 0.790-0.991, p = 0.034), orientation to place (95% CI 0.307-0.911, p = 0.022) and registration (95% CI 0.162-0.768, p = 0.009) were significantly associated with falls in the follow-up.

CONCLUSION

Our study found that in patients with DM, cognitive function is related to future falls. Not only overall cognitive function, but also orientation to place and registration were all associated with future falls in older adults with DM. When completing the fall risk assessment of elderly patients with DM, clinicians should give more attention to the testing of cognitive function.