Search Results (66)

Podocytopathy, characterized by proteinuria, contributes significantly to kidney diseases, with hypertension playing a key role in damaging podocytes and the glomerular filtration barrier (GFB). The lack of functional in vitro models, however, impedes research and treatment development for hypertensive podocytopathy. We established a novel constant pressure-driven podocyte-on-chip model, utilizing our previously developed dynamic staining self-assembly cell array chip (SACA chip) and 3D printing. This platform features a differentiated podocyte monolayer under controlled hydrostatic pressures, mimicking the epithelial side of the GFB. Using this platform, we investigated mechanical force-dependent permeability to three sizes of fluorescent dextran under varying hydrostatic pressures, comparing the results with a puromycin aminonucleoside (PAN)-induced injury model. We observed that external pressures induced size-dependent permeability changes and altered cell morphology. Higher pressures led to greater macromolecule infiltration, especially for larger dextran (70 kDa, 500 kDa). Mature podocytes exhibited immediate, pressure-dependent cytoskeleton rearrangements, with better recovery at lower pressures (20 mmHg) but irreversible injury at higher pressures (40, 60 mmHg). These morphological changes were also corroborated by dynamic mRNA expression of cytoskeleton-associated proteins, Synaptopodin and ACTN4. This platform offers a promising in vitro tool for investigating the pathomechanisms of hypertension-induced podocytopathy, performing on-chip studies of the GFB, and conducting potential drug screening. Full article

Patients with end-stage renal disease (ESRD) are at increased risk of cardiovascular disease (CVD), such as myocardial infarction (MI). Uremic toxins and endothelial dysfunction are central to this process. In this exploratory study, we used the Affymetrix GeneChip microarray to investigate the gene expression profile in uremic serum-induced human coronary arterial endothelial cells (HCAECs) from ESRD patients with and without MI (UWI and UWOI groups) as an approach to its underlying mechanism. We also explored which pathways are involved in this process. We found 100 differentially expressed genes (DEGs) among the conditions of interest by supervised principal component analysis and hierarchical cluster analysis. The expressions of four major DEGs were validated by quantitative RT-PCR. Pathway analysis and molecular network were used to analyze the interaction and expression patterns. Ten pathways were identified as the main enriched metabolic pathways according to the transcriptome profiling analysis, which were, among others, positive regulation of inflammatory response, positive regulation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) cascade, cardiac muscle cell development, highlighting positive regulation of mitogen-activated protein kinase (MAPK) activity (p = 0.00016). Up- and down-regulation of genes from HCAECs exposed to uremic serum could contribute to increased endothelial dysfunction and CVD in ESRD patients. Our study suggests that inflammation and the ERK-MAPK pathway are highly enriched in kidney disease patients with MI, suggesting their role in ESRD pathology. Further studies and approaches based on MAPK pathway interfering strategies are needed to confirm these data. Full article

An ultra-low-power implantable body temperature sensor with a power consumption of 40.9 nW is presented. Deep body temperature measurement can be utilized for diseases such as inflammatory response due to implantable devices, treatment of traumatic brain injury, early monitoring of rejection after kidney transplantation, and monitoring of frictional heat in artificial joints, as well as health management such as ovulation cycles. Since it is implanted in the body and operated by a battery, it is very important to minimize power consumption. For low power consumption, we propose a dynamic virtual Wheatstone bridge technology for low-power transducer driving, and the simplified architecture is designed to operate at 0.6 V. The chip fabricated in a 180 nm CMOS process meets the ASTM E1112-00 specification for medical thermometers. That is, it can measure from 34 °C to 43 °C and meets the accuracy of ±0.1 °C between 37 °C and 39 °C. The measured power consumption at 37 °C is 40.9 nW. To verify practical application, a temperature sensor was implanted in a rat and body temperature changes before and after anesthesia were observed. Full article

A microfluidic system for detecting sodium ions (Na⁺) has been developed, incorporating a micro finger-pump chip and a micro-spectrometer platform to measure Na⁺ concentration in human serum. A small volume (10 μL) of serum sample is introduced into the microchip and reacted with a preloaded reagent mixture through a two-step finger-pump actuation process. The resulting purple complex is directed into the detection area of the chip and analyzed using the micro-spectrometer at wavelengths of 555 and 666 nm. The Na⁺ concentration is then inversely derived from the measured A₅₅₅/A₆₆₆ absorbance ratio using self-written software installed on a Raspberry Pi. The entire detection process is completed in just 3 min, offering a significant advantage in meeting clinical needs compared to the traditional reporting turnaround time of several hours in medical institutions. The experimental results indicate a linear relationship between the measured absorbance ratio and Na⁺ concentration within the range of 1–200 mM, with a correlation coefficient of R² = 0.9989. Additionally, the detection results from 60 serum samples collected from chronic kidney disease (CKD) patients showed a strong agreement with those obtained using the conventional indirect ion-selective electrode (ISE) method, achieving a correlation coefficient of R² = 0.9885 and an average recovery rate of 99.4%. In summary, the proposed system provides a practical, affordable, and rapid alternative to conventional Na⁺ detection methods, making it highly promising for point-of-care (POC) testing applications. Full article

The development of bionic organ-on-a-chip technology relies heavily on advancements in in situ sensors and biochip packaging. By integrating precise biological and fluid condition sensing with microfluidics and electronic components, long-term dynamic closed-loop culture systems can be achieved. This study aims to develop biocompatible heterogeneous packaging and laser surface modification techniques to enable the encapsulation of electronic components while minimizing their impact on fluid dynamics. Using a kidney-on-a-chip as a case study, a non-toxic packaging process and fluid interface control methods have been successfully developed. Experimentally, miniature pressure sensors and control circuit boards were encapsulated using parylene-C, a biocompatible material, to isolate biochemical fluids from electronic components. Ultraviolet laser processing was employed to fabricate structures on parylene-C. The results demonstrate that through precise control of processing parameters, the wettability of the material can be tuned freely within a contact angle range of 60° to 110°. Morphological observations and MTT assays confirmed that the material and the processing methods do not induce cytotoxicity. This technology will facilitate the packaging of various miniature electronic components and biochips in the future. Furthermore, laser processing enables rapid and precise control of interface conditions across different regions within the chip, demonstrating a high potential for customized mass production of biochips. The proposed innovations provide a solution for in situ sensing in organ-on-a-chip systems and advanced biochip packaging. We believe that the development of this technology is a critical step toward realizing the concept of “organ twin”. Full article

Clonal hematopoiesis (CH) is associated with an increased risk of developing myeloid neoplasms (MNs) such as myelodysplastic neoplasm (MDS) and acute myeloid leukemia (AML). In general, CH comprises clonal hematopoiesis of indeterminate potential (CHIP) and clonal cytopenia of undetermined significance (CCUS). It is an age-related phenomenon characterized by the presence of somatic mutations in hematopoietic stem cells (HSCs) and hematopoietic stem and progenitor cells (HSPCs) that acquire a fitness advantage under selection pressure. Individuals with CHIP have an absolute risk of 0.5–1.0% per year for progressing to MDS or AML. Inflammation, smoking, cytotoxic therapy, and radiation can promote the process of clonal expansion and leukemic transformation. Of note, exposure to chemotherapy or radiation for patients with solid tumors or lymphomas can increase the risk of therapy-related MN. Beyond hematological malignancies, CH also serves as an independent risk factor for heart disease, stroke, chronic obstructive pulmonary disease, and chronic kidney disease. Prognostic models such as the CH risk score and MN-prediction models can provide a framework for risk stratification and clinical management of CHIP/CCUS and identify high-risk individuals who may benefit from close surveillance. For CH or related disorders, therapeutic strategies targeting specific CH-associated mutations and specific selection pressure may have a potential role in the future. Full article

Growing concerns about the health risks of melamine adulteration in food products highlight the urgent need for reliable detection methods. However, the long-term effects of chronic low-level melamine exposure remain inadequately explored. This study introduces THE ONE InstantCare platform, a portable immunoassay analyzer integrating a SpectroChip-based spectral processing unit (SPU) with lateral flow immunoassay (LFIA) for sensitive and accurate quantification of melamine in human urine. This platform provides a cost-effective, rapid, and user-friendly point-of-care (POC) solution for melamine detection. Analytical evaluations across eight melamine concentrations (0–100 parts per billion, ppb) achieved a limit of detection (LOD) of 1.91 ppb. Validation with 24 human urine samples demonstrated strong concordance with liquid chromatography–mass spectrometry (LC-MS), yielding an intraclass correlation coefficient (ICC) of 0.9220, a Pearson correlation coefficient of 0.9389, and 95% agreement in Bland–Altman analysis. High reproducibility was observed, with an intraday coefficient of variation (CV) of 6.53% and acceptable interday CV values, while interference studies confirmed reliability in the presence of common biological substances. By delivering results in approximately 10 min, THE ONE InstantCare platform significantly reduces analysis time compared to LC-MS, which typically requires several hours. This novel platform enhances food safety surveillance and advances human health risk assessments, particularly for evaluating melamine-linked kidney damage. Its versatility and robust performance make it a promising tool for environmental monitoring and clinical diagnostics, enabling the detection of diverse biomarkers with high sensitivity and reproducibility. Full article

This review explores the significant role of microfluidic technologies in advancing cancer research, focusing on the below key areas: droplet-based microfluidics, organ-on-chip systems, paper-based microfluidics, electrokinetic chips, and microfluidic chips for the study of immune response. Droplet-based microfluidics allows precise manipulation of cells and three-dimensional microtissues, enabling high-throughput experiments that reveal insights into cancer cell migration, invasion, and drug resistance. Organ-on-chip systems replicate human organs to assess drug efficacy and toxicity, particularly in the liver, heart, kidney, gut, lung, and brain. Paper-based microfluidics offers an alternative approach to accomplish rapid diagnostics and cell- and tissue-based bioassays. Electrokinetic microfluidic chips offer precise control over cell positioning and behavior, facilitating drug screening and cellular studies. Immune response studies leverage real-time observation of interactions between immune and cancer cells, supporting the development of immunotherapies. These microfluidic advances are paving the way for personalized cancer treatments while addressing challenges of scalability, cost, and clinical integration. Full article

Up to 40% of patients with diabetes mellitus will develop diabetic kidney disease (DKD), characterized pathologically by the accumulation of extracellular matrix proteins, which leads to the loss of kidney function over time. Our previous studies showed that the pan-protease inhibitor alpha 2-macroglobulin (A2M) is increased in DKD and is a critical regulator of the fibrotic response in glomerular mesangial cells (MC), an initial site of injury during DKD development. How A2M is regulated by high glucose (HG) has not yet been elucidated and is the focus of this investigation. Using serial deletions of the full A2M promoter, we identified the −405 bp region as HG-responsive in MC. Site-directed mutagenesis, siRNA, and ChIP studies showed that the transcription factor, nuclear factor of activated T cells 5 (NFAT5), regulated A2M promoter activity and protein expression in response to HG. Forkhead box P1 (FOXP1) served as a cooperative binding partner for NFAT5, required for A2M upregulation. Lastly, we showed that Smad3, known for its role in kidney fibrosis, regulated A2M promoter activity and protein production independently of HG. The importance of NFAT5, FOXP1, and Smad3 in A2M regulation was confirmed in ex vivo studies using isolated glomeruli. In conclusion, Smad3 is required for basal and HG-induced A2M expression, while NFAT5 and FOXP1 cooperatively regulate increased A2M transcription in response to HG. Inhibition of NFAT5/FOXP1 will be further evaluated as a potential therapeutic strategy to inhibit A2M production and attenuate profibrotic signaling in DKD. Full article

Background/Objectives: High fructose has been implicated as an important trigger of kidney inflammation in patients and experimental models. Magnolol, isolated from Magnolia officinalis, has an anti-inflammatory effect, but its protective role in podocytes remains underexplored. This study explored the protective effects and underlying mechanism of magnolol against high fructose-induced podocyte inflammation. Methods: The effects of magnolol on high fructose-induced podocyte inflammation were assessed in male Sprague Dawley rats administered 10% (w/v) fructose water for 12 weeks and heat-sensitive human podocyte cell lines (HPCs) exposed to 5 mM fructose. Podocyte foot processes were examined using transmission electron microscopy. The expression levels of nephrin, podocin, tumor necrosis factor-α (TNF-α), Notch1 intracellular domain (NICD1), triokinase/FMN cyclase (TKFC), specificity protein 1 (Sp1) and histone deacetylase 4 (HDAC4) were determined by Western blot, immunofluorescence and real-time quantitative polymerase chain reaction (qRT-PCR). The chromatin immunoprecipitation (ChIP) assay was performed to evaluate the interaction between Sp1 and the promoter region of HDAC4. Results: Magnolol mitigated the impairment of glomerular filtration function in high fructose-fed rats. Besides, it significantly alleviated the inflammatory responses in glomeruli and HPCs, evidenced by decreased protein levels of TNF-α and NICD1. Increased protein levels of TKFC, Sp1 and HDAC4 were observed in high fructose-stimulated HPCs and rat glomeruli. TMP195, an HDAC4 inhibitor, reduced TNF-α and NICD1 protein levels in high fructose-exposed HPCs. The increased Sp1 was shown to associate with the promoter region of HDAC4, promoting HDAC4 protein expression in high fructose-exposed HPCs. The knockdown of TKFC in HPCs by TKFC siRNA decreased Sp1, HDAC4 and NICD1 protein levels, alleviating podocyte inflammatory response. Furthermore, magnolol inhibited TKFC/Sp1/HDAC4/Notch1 activation in vivo and in vitro. Conclusions: Magnolol attenuated high fructose-induced podocyte inflammation possibly through the suppression of TKFC/Sp1/HDAC4/Notch1 activation, providing new evidence for its potential role in podocyte protection. Full article

Advanced glycated end products (AGEs) are cytotoxic compounds that are mainly increased in diabetes mellitus (DM), kidney failure, inflammation, and in response to the ingestion of AGE-rich diets. AGEs can also impair glycemic homeostasis by decreasing the expression of the Slc2a4 (solute carrier family 2 member 4) gene and its GLUT4 (solute carrier family 2, facilitated glucose transporter member 4) protein in muscle. However, the mechanisms underlying AGE’s effect on adipocytes have not been demonstrated yet. This study investigated the effects of AGEs upon Slc2a4/GLUT4 expression in 3T3-L1 adipocytes, as well as the potential role of NFKB (nuclear factor NF-kappa-B) activity in the effects observed. Adipocytes were cultured in the presence of control albumin (CA) or advanced glycated albumin (GA) at concentrations of 0.4, 3.6, and 5.4 mg/mL for 24 h or 72 h. Slc2a4, Rela, and Nfkb1mRNAs were measured by RT-qPCR, GLUT4, IKKA/B, and p50/p65 NFKB subunits using Western blotting, and p50/p65 binding into the Slc2a4 promoter was analyzed by chromatin immunoprecipitation (ChIP) assay. GA at 0.4 mg/mL increased Slc2a4/GLUT4 expression after 24 h and 72 h (from 50% to 100%), but at 5.4 mg/mL, Slc2a4/GLUT4 expression decreased at 72 h (by 50%). Rela and Nfkb1 expression increased after 24 h at all concentrations, but this effect was not observed at 72 h. Furthermore, 5.4 mg/mL of GA increased the p50/p65 nuclear content and binding into Slc2a4 at 72 h. In summary, this study reveals AGE-induced and NFKB-mediated repression of Slc2a4/GLUT4 expression. This can compromise the adipocyte glucose utilization, contributing not only to the worsening of glycemic control in DM subjects but also the impairment of glycemic homeostasis in non-DM subjects under the high intake of AGE-rich foods. Full article

Nephrotoxicity stands as one of the most limiting effects in the development and validation of new drugs. The kidney, among the organs evaluated in toxicity assessments, has a higher susceptibility, with nephrotoxic potential frequently evading detection until late in clinical trials. Traditional cell culture, which has been widely used for decades, does not recapitulate the structure and complexity of the native tissue, which can affect cell function, and the response to cytotoxins does not resemble what occurs in the kidney. In the current study, we aimed to address these challenges by creating in vitro kidney models that faithfully biomimic the dynamics of the renal proximal tubule, using the well-established RPTEC/TERT1 cell line. For doing so, two models were developed, one recreating tubule-like structures (2.5D model) and the other using microfluidic technology (kidney-on-a-chip). The 2.5D model allowed tubular structures to be generated in the absence of hydrogels, and the kidney-on-a-chip model allowed shear stress to be applied to the cell culture, which is a physiological stimulus in the renal tissue. After characterization of both models, different nephrotoxic compounds such as cisplatin, tacrolimus, and daunorubicin were used to study cell responses after treatment. The developed models in our study could be a valuable tool for pre-clinical nephrotoxic testing of drugs and new compounds. Full article

Undernutrition (UN) increases child vulnerability to illness and mortality. Caused by a low amount and/or poor quality of food intake, it impacts physical, cognitive, and social development. Modern types of food consumption have given highly processed food a higher cultural value compared to minimally processed food. Objective: The objective of this study was to evaluate the effect on growth, metabolism, physical activity (PA), memory, inflammation, and toxicity of an enriched black corn chip (BC) made with endemic ingredients on post-weaned UN mice. Methods: A chip was made with a mixture of black corn, fava beans, amaranth, and nopal cactus. To probe the effects of UN, UN was induced in 3wo post-weaned male C57Bl/6j mice through a low-protein diet (LPD—50% of the regular requirement of protein) for 3w. Then, the BC was introduced to the animals’ diet (17%) for 5w; murinometric parameters were measured, as were postprandial glucose response, PA, and short-term memory. Histological analysis was conducted on the liver and kidneys to measure toxicity. Gene expression related to energy balance, thermogenesis, and inflammation was measured in adipose and hypothalamic tissues. Results: Treatment with the BC significantly improved mouse growth, even with a low protein intake, as evidenced by a significant increase in body weight, tail length, cerebral growth, memory improvement, physical activation, normalized energy expenditure (thermogenesis), and orexigenic peptides (AGRP and NPY). It decreased anorexigenic peptides (POMC), and there was no tissue toxicity. Conclusions: BC treatment, even with persistent low protein intake, is a promising strategy against UN, as it showed efficacy in correcting growth deficiency, cognitive impairment, and metabolic problems linked to treatment by adjusting energy expenditure, which led to the promotion of energy intake and regulation of thermogenesis, all by using low-cost, accessible, and endemic ingredients. Full article

A microfluidic immuno-biosensor detection system consisting of a microfluidic spectrum chip and a micro-spectrometer detection device is presented for the rapid point-of-care (POC) detection and quantification of high-sensitivity C-reactive protein (hs-CRP) in urine. The detection process utilizes a highly specific enzyme-linked immunosorbent assay (ELISA) method, in which capture antibodies and detection antibodies are pre-deposited on the substrate of the microchip and used to form an immune complex with the target antigen. Horseradish peroxidase (HRP) is added as a marker enzyme, followed by a colorimetric reaction using 3,3′,5,5′-tetramethylbenzidine (TMB). The absorbance values (a.u.) of the colorimetric reaction compounds are measured using a micro-spectrometer device and used to measure the corresponding hs-CRP concentration according to the pre-established calibration curve. It is shown that the hs-CRP concentration can be determined within 50 min. In addition, the system achieves recovery rates of 93.8–106.2% in blind water samples and 94.5–104.6% in artificial urine. The results showed that the CRP detection results of 41 urine samples from patients with chronic kidney disease (CKD) were highly consistent with the conventional homogeneous particle-enhanced turbidimetric immunoassay (PETIA) method’s detection results (R² = 0.9910). The experimental results showed its applicability in the detection of CRP in both urine and serum. Overall, the results indicate that the current microfluidic ELISA detection system provides an accurate and reliable method for monitoring the hs-CRP concentration in point-of-care applications. Full article

Glomerulonephritis (GN) is characterized by podocyte injury or glomerular filtration dysfunction, which results in proteinuria and eventual loss of kidney function. Progress in studying the mechanism of GN, and developing an effective therapy, has been limited by the absence of suitable in vitro models that can closely recapitulate human physiological responses. We developed a microfluidic glomerulus-on-a-chip device that can recapitulate the physiological environment to construct a functional filtration barrier, with which we investigated biological changes in podocytes and dynamic alterations in the permeability of the glomerular filtration barrier (GFB) on a chip. We also evaluated the potential of GN-mimicking devices as a model for predicting responses to human GN. Glomerular endothelial cells and podocytes successfully formed intact monolayers on opposite sides of the membrane in our chip device. Permselectivity analysis confirmed that the chip was constituted by a functional GFB that could accurately perform differential clearance of albumin and dextran. Reduction in cell viability resulting from damage was observed in all serum-induced GN models. The expression of podocyte-specific marker WT1 was also decreased. Albumin permeability was increased in most models of serum-induced IgA nephropathy (IgAN) and membranous nephropathy (MN). However, sera from patients with minimal change disease (MCD) or lupus nephritis (LN) did not induce a loss of permeability. This glomerulus-on-a-chip system may provide a platform of glomerular cell culture for in vitro GFB in formation of a functional three-dimensional glomerular structure. Establishing a disease model of GN on a chip could accelerate our understanding of pathophysiological mechanisms of glomerulopathy. Full article