Determination of triglycerides with special emphasis on biosensors: A review

Associations of lipids in adolescence and adulthood with self- and other-directed compassion in adulthood

Self- and other-directed compassion have been linked with better mental and physical health but research on factors contributing to their development is scarce. Previous studies indicate a possible causal relationship of lipids with personality and socioemotional functioning. As an extension to earlier research, in the present study we examine whether lipids assessed in adolescence and adulthood are associated with self-compassion and other-directed compassion in adulthood. The study utilizes data on lipids from two follow-ups in the Northern Finland Birth Cohort 1986 at ages 15-16 and 33-35. In the latter follow-up also self-compassion and other-directed compassion were assessed with the self-compassion scale - short form and the subscale for compassion in the dispositional positive emotions scale, respectively. The sample for the cross-sectional associations of lipids in adulthood with the compassion variables in adulthood includes 1,459 participants, whereas the sample for the longitudinal associations of lipids in adolescence and the compassion variables in adulthood consists of 1,509 participants. The associations were examined with hierarchical linear regression (lipids as continuous variables) and univariate general linear model (lipids as categorical variables). The results suggest that in women, high-density lipoprotein (HDL) cholesterol in adolescence is associated with high empathic concern (a component of other-directed compassion) in adulthood. The results show further that, in women, an HDL cholesterol level above 1.2 mmol/L in adulthood is associated with high other-directed compassion and empathic concern in adulthood. The present study provides tentative evidence that biological factors such as lipids might play a role in the development of empathic concern and other-directed compassion.

Altered lipidomics biosignatures in schizophrenia: A systematic review

Multiomics approaches have significantly aided the identification of molecular signatures in complex neuropsychiatric disorders. Lipidomics, one of the newest additions in the -omics family, sheds light on lipid profiles and is an emerging methodological tool to study schizophrenia pathobiology, as lipid dysregulation has been repeatedly observed in schizophrenia. In this review, we performed a detailed literature search for lipidomics studies in schizophrenia. Following elaborate inclusion/exclusion criteria, we focused on human studies in schizophrenia and schizophrenia-related diagnoses in brain and blood specimens, including serum plasma, platelets and red blood cells. Eighteen studies fulfilled our inclusion criteria, of which five were conducted in the brain, 12 in peripheral material and one in both. Here, we first provide background on lipidomics and the main lipid categories addressed, review in detail the included literature and look for common lipidomics patterns in brain and the periphery that emerge from these studies. Furthermore, we highlight current limitations in schizophrenia lipidomics research and underline the need for following up on lipidomics results with complementary molecular approaches.

A highly sensitive optical fiber sensor enables rapid triglycerides-specific detection and measurement at different temperatures using convolutional neural networks

For specific recognition and sensitive detection of triglycerides (TGs), an optical fiber sensor (OFS) based on an enhanced core diameter mismatch was proposed. The sensitivity of the sensor is significantly increased due to the repetitive excitation of the higher-order cladding modes. A technique for immobilizing lipase using covalent binding technology was presented and demonstrated by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy. The interference dip of the sensor was shifted due to TGs being hydrolyzed in the presence of lipase. The sensor shows an optimal response within 3 min and exhibits a high sensitivity of 0.9933 nm/(mg/ml) and a limit of detection of 0.0822 mg/ml in the concentration range 0-8 mg/ml at a temperature of 37 °C and a pH of 7.4. The response of the sensor to TGs concentration at different temperatures and pH was investigated. The reproducibility, reusability, and stability of the proposed sensor were tested and verified experimentally. The biosensor is highly specific for TGs and unaffected by many other interfering substances. Further, the measurement of TGs concentration at different temperatures was realized. This method provides a new way to detect TGs rapidly and reliably and has potential applications in medical research and clinical diagnosis.

A bifunctional anti-PCSK9 scFv/Exendin-4 fusion protein exhibits enhanced lipid-lowering effects via targeting multiple signaling pathways in HFD-fed mice

Fusion protein which encompasses more than one functional component, has become one of the most important representatives of macromolecular drugs for disease treatment since that monotherapy itself might not be effective enough to eradicate the disease. In this study, we sought to construct a bifunctional antibody fusion protein by fusing anti-PCSK9 scFv with Exendin-4 for simultaneously lowering both LDL-C and TG. Firstly, three Ex4-anti-PCSK9 scFv fusion proteins were constructed by genetically connecting the C-terminal of Exendin-4 to the N-terminal of anti-PCSK9 scFv through various flexible linker peptides (G4S)n (n = 2, 3, 4). After soluble expression in E. coli, the most potent Ex4-(G4S)4-anti-PCSK9 scFv fusion protein was selected based on in vitro activity assays. Then, we investigated the in vivo therapeutic effects of Ex4-(G4S)4-anti-PCSK9 scFv on the serum lipid profile and bodyweight changes as well as underlying molecular mechanism in HFD-fed C57BL/6 mice. The data showed that Ex4-(G4S)4-anti-PCSK9 scFv exhibits enhanced effects of lowering both LDL-C and TG in serum, reducing food intake and body weight via blocking PCSK9/LDLR, activating AMPK/SREBP-1 pathways, and up-regulating sirt6. Conclusively, Ex4-(G4S)4-anti-PCSK9 has the potential to serve as a promising therapeutic agent for effectively treating dyslipidemia with high levels of both LDL-C and TG.

Fish consumption and its lipid modifying effects - A review of intervention studies

Fish is an important source of nutrients, particularly the long chain n-3 polyunsaturated fatty acids (n-3 PUFAs). The incorporation of fish into the diet has been shown to have several health benefits, including lowering the risk of cardiovascular disease (CVD). Elevated plasma lipids are one of the main modifiable risk factors contributing to CVD and may be partly mediated by n-3 PUFAs. Although n-3 PUFAs in the form of supplementation have been shown to exert lipid modifying effects, the effects of fish consumption on the lipid profile have not been well summarised to date. Therefore, the aim of the present review is to discuss the current evidence from intervention studies investigating the effect of fish consumption on the lipid profile in both apparently healthy and non-healthy populations. Existing evidence appears to support the role of fish in promoting a shift towards a less inflammatory lipid profile through raising n-3 PUFAs and potentially lowering n-6 PUFA and triglyceride concentrations in both healthy and non-healthy populations. Fish consumption has a negligible effect on cholesterol concentrations; however, fish consumption may promote a small increase in high density lipoprotein (HDL) cholesterol amongst people with lower HDL at baseline. Limited studies have shown fish consumption to result in shifts in phospholipid and sphingolipid species and structure, albeit it is not yet clear whether these alterations have any meaningful impact on CVD risk. Future well-designed studies that utilise NMR and/or lipidomics analysis are warranted to explore the effects of these shifts in lipid content and structure in the context of disease development. Public health guidance should emphasise the cardioprotective benefits of fish and encourage consumption particularly in the Global North where fish consumption remains low.

Metabolic disturbance and transcriptomic changes induced by methyl triclosan in human hepatocyte L02 cells

PURPOSE

Methyl triclosan (MTCS) is one of the biomethylated by-products of triclosan (TCS). With the increasing use of TCS, the adverse effects of MTCS have attracted extensive attention in recent years. The purpose of this study was to investigate the cytotoxicity of MTCS and to explore the underlining mechanism using human hepatocyte L02 cells as in vitro model.

RESULTS

The cytotoxicity results revealed that MTCS could inhibit cell viability, disturb the ratio of reduced glutathione (GSH) and oxidized glutathione (GSSG), and reduce the mitochondrial membrane potential (MMP) in a dose-dependent manner. In addition, MTCS exposure significantly promoted the cellular metabolic process, including enhanced conversion of glucose to lactic acid, and elevated content of intracellular triglyceride (TG) and total cholesterol (TC). RNA-sequencing and bioinformatics analysis indicated disorder of glucose and lipid metabolism was significantly induced after MTCS exposure. Protein-protein interaction network analysis and node identification suggested that Serine hydroxy methyltransferase 2 (SHMT2), Methylenetetrahydrofolate dehydrogenase 2 (MTHFD2), Asparagine synthetase (ASNS) and Phosphoglycerate dehydrogenase (PHGDH) are potential molecular markers of metabolism imbalance induced by MTCS.

CONCLUSION

These results demonstrated that oxidative stress and metabolism dysregulation might be involved in the cytotoxicity of MTCS in L02 cells.

Development and Evaluation of a Low-Cost Triglyceride Quantification Enzymatic Biosensor Using an Arduino-Based Microfluidic System

Overweight and obesity promote diabetes and heart disease onset. Triglycerides are key biomarkers for cardiovascular disease, strokes, and other health issues. Scientists have devised methods and instruments for the detection of these molecules in liquid samples. In this study, an enzymatic biosensor was developed using an Arduino-based microfluidic platform, wherein a lipolytic enzyme was immobilized on an ethylene-vinyl acetate polymer through physical adsorption. This low-cost optical biosensor employed a spectrophotometric transducer and was assessed in liquid samples to indirectly detect triglycerides and fatty acids using p-nitrophenol as an indicator. The average triglyceride level detected in the conducted experiments was 47.727 mg/dL. The biosensor exhibited a percentage of recovery of 81.12% and a variation coefficient of 0.791%. Furthermore, the biosensor demonstrated the ability to detect triglyceride levels without the need for sample dilution, ranging from 7.6741 mg/dL to 58.835 mg/dL. This study successfully developed an efficient and affordable enzymatic biosensor prototype for triglyceride and fatty acid detection. The lipolytic enzyme immobilization on the polymer substrate provided a stable and reproducible detection system, rendering this biosensor an exciting option for the detection of these molecules.

Serum 25(OH)D Levels Modify the Association between Triglyceride and IR: A Cross-Sectional Study

BACKGROUND

Triglycerides and 25(OH)D had been reported as correlates of IR, but the results suggest substantial heterogeneity across races. In addition, little research reported on whether different 25(OH)D levels affect triglycerides and IR. Therefore, a similar study on the US population would be a great addition to the current one. This study investigated the association between triglycerides and IR at different 25(OH)D levels.

METHODS

A total of 19,926 participants were included, each containing specific indicators for the study project. IR was estimated as a HOMA-IR index ≥2.73. Four multivariate logistic regression models were developed to analyze the association between TG and IR and whether different 25(OH)D levels influenced this association. Smoothed fitting curves were plotted.

RESULTS

Triglyceride was significantly associated with IR (OR: 1.3, 95 CI %), while this association received different 25(OH)D levels (P for interaction <0.001). The effect value OR was 1.33 with the high levels, and its effect value OR was 1.28 with the low levels.

CONCLUSION

This study demonstrates that triglyceride levels are significantly associated with insulin in the US adult population and can be used as a predictor of IR. This correlation was compromised at different 25 (OH)D levels, so future studies need to be explored in more ethnically diverse contexts.

Dual-fiber optic bioprobe system for triglyceride detection using surface plasmon resonance sensing and lipase-immobilized magnetic bead hydrolysis

The rapid and accurate detection of triglyceride (TG) plays a valuable role in the prevention and control of dyslipidemia. In this paper, a novel method for TG detection using a dual-fiber optic bioprobe system, which can accurately detect different levels of TG concentration in serum, is proposed. The system employs disposable microprobe-type fiber optic surface plasmon resonance (SPR) biosensors for signal acquisition, providing high stability and portability while avoiding cross-contamination caused by repeated use. The proposed biosensor with a high sensitivity of 1.25 nm/(mg/mL) for TG detection in serum and a tiny diameter of 125 μm, was fabricated using a novel multimode fiber-single-mode fiber-reflector (MSR) structure, which has been scarcely ever reported to the best of our knowledge. In the process of TG detection, lipase-immobilized magnetic beads were introduced to specifically hydrolyze TG, and the relationship between the TG content and the SPR differential signal was obtained from dual-fiber optic bioprobe measurements of the TG sample before and after hydrolysis. The proposed method achieved TG detection in the concentration range of 0-8 mg/mL (including healthy and unhealthy levels of TG concentration in the human body). Additionally, the miniaturized fiber optic biosensors used in this work have the advantages of low sample consumption, high sensitivity, simple operation, label-free measurement, high selectivity, and low cost. This method provides a new pathway for rapid and reliable TG detection and has potential applications in medical research and clinical diagnosis.

Development of Screen-Printed Electrode Biosensor for Rapid Determination of Triglyceride Content in Coconut Milk

The screen-printed electrode biosensor was developed for triglyceride determination in coconut milk. The biosensor was developed by adding lipase, glycerol-3-phosphate (GPO), and glycerol kinase (GK), which is immobilized to a gelatin solution. The concentration of triglyceride is found to be linear to the current produced. The developed screen-printed electrode biosensor showed the optimum response for pH 7.0, 45 mg amount of gelatin, 2.5% glutaraldehyde concentration solution. The developed biosensor was able to find triolein concentrations 0.1 to 1.5 mM. The correlation obtained between these two methods was 93% which was found to be good.

Bi-enzyme functionalized electro-chemically reduced transparent graphene oxide platform for triglyceride detection

Recently, increased attention has been drawn to application of graphene and its derivatives for construction of biosensors, since they can be used to rapidly detect the presence of bio-analytes.

Nanomaterial-based biosensors for measurement of lipids and lipoproteins towards point-of-care of cardiovascular disease

Cardiovascular disease (CVD) has become the primary cause of global deaths and inflicts an enormous healthcare burden on both developed and developing countries. Frequent monitoring of CVD-associated risk factors such as the level of lipids (e.g., triglyceride (TG) and total cholesterol (TC)) and lipoproteins (e.g., low-density lipoprotein (LDL) and high-density lipoprotein (HDL)) can effectively help prevent disease progression and improve clinical outcomes. However, measurement of these risk factors is generally integrated into an automated analyzer, which is prohibitively expensive and highly instrument-dependent for routine testing in primary care settings. As such, a variety of rapid, simple and portable nanomaterial-based biosensors have been developed for measuring the level of lipids (TG and TC) and lipoproteins (LDL and HDL) towards the management of CVD at the point-of-care (POC). In this review, we first summarize traditional methods for measurement of lipids and lipoproteins, and then present the latest advances in developing nanomaterial-based biosensors that can potentially monitor the risk factors of CVD at the POC.

Biosensors Incorporating Bimetallic Nanoparticles

This article presents a review of electrochemical bio-sensing for target analytes based on the use of electrocatalytic bimetallic nanoparticles (NPs), which can improve both the sensitivity and selectivity of biosensors. The review moves quickly from an introduction to the field of bio-sensing, to the importance of biosensors in today's society, the nature of the electrochemical methods employed and the attendant problems encountered. The role of electrocatalysts is introduced with reference to the three generations of biosensors. The contributions made by previous workers using bimetallic constructs, grouped by target analyte, are then examined in detail; following which, the synthesis and characterization of the catalytic particles is examined prior to a summary of the current state of endeavor. Finally, some perspectives for the future of bimetallic NPs in biosensors are given.

A nanostructured conductive hydrogels-based biosensor platform for human metabolite detection

The development of a scalable, low-cost, and versatile biosensor platform for the sensitive and rapid detection of human metabolites is of great interest for healthcare, pharmaceuticals, and medical science. On the basis of hierarchically nanostructured conducting polymer hydrogels, we designed a flexible biosensor platform that can detect various human metabolites, such as uric acid, cholesterol, and triglycerides. Owing to the unique features of conducting polymer hydrogels, such as high permeability to biosubstrates and rapid electron transfer, our biosensors demonstrate excellent sensing performance with a wide linear range (uric acid, 0.07-1 mM; cholesterol, 0.3-9 mM, and triglycerides, 0.2-5 mM), high sensitivity, low sensing limit, and rapid response time (∼3 s). Given the facile and scalable processability of hydrogels, the proposed conductive hydrogels-based biosensor platform shows great promise as a low-cost sensor kit for healthcare monitoring, clinical diagnostics, and biomedical devices.