Ethanolamine as a biomarker and biomarker-based therapy for diabetic retinopathy in glucose-well-controlled diabetic patients.

Diabetic retinopathy (DR) is the leading cause of blindness among the working-age population. Although controlling blood glucose levels effectively reduces the incidence and development of DR to less than 50%, there are currently no diagnostic biomarkers or effective treatments for DR development in glucose-well-controlled diabetic patients (GW-DR). In this study, we established a prospective GW-DR cohort by strictly adhering to glycemic control guidelines and maintaining regular retinal examinations over a median 2-year follow-up period. The discovery cohort encompassed 71 individuals selected from a pool of 292 recruited diabetic patients at baseline, all of whom consistently maintained hemoglobin A1c (HbA1c) levels below 7% without experiencing hypoglycemia. Within this cohort of 71 individuals, 21 subsequently experienced new-onset GW-DR, resulting in an incidence rate of 29.6%. In the validation cohort, we also observed a significant GW-DR incidence rate of 17.9%. Employing targeted metabolomics, we investigated the metabolic characteristics of serum in GW-DR, revealing a significant association between lower levels of ethanolamine and GW-DR risk. This association was corroborated in the validation cohort, exhibiting superior diagnostic performance in distinguishing GW-DR from diabetes compared to the conventional risk factor HbA1c, with AUCs of 0.954 versus 0.506 and 0.906 versus 0.521 in the discovery and validation cohorts, respectively. Furthermore, in a streptozotocin (STZ)-induced diabetic rat model, ethanolamine attenuated diabetic retinal inflammation, accompanied by suppression of microglial diacylglycerol (DAG)-dependent protein kinase C (PKC) pathway activation. In conclusion, we propose that ethanolamine is a potential biomarker and represents a viable biomarker-based therapeutic option for GW-DR.

Synthesis and highly efficient photocatalysis applications of CdS QDs and Au NPs Co-modified KTaO3 perovskite cubes.

Perovskite structure has attracted interest for the past few years due to its prospects in photocatalysis. The exploration of efficient perovskite photocatalysts still receives much attention in the field of chemistry and materials science. Herein, KTaO3 cubes are first prepared by hydrothermal synthesis, then Au nanoparticles (NPs) are loaded on the cubes by photodeposition, and finally, CdS quantum dots (QDs) are modified on Au/KTaO3 cubes using an in situ growth method, and eventually tantalum-based photocatalysts in a ternary system are successfully prepared. The fabricated CdS/Au/KTaO3 reveals photocatalytic properties in hydrogen evolution and degradation of dyes. In particular, under the same conditions, the photocatalytic hydrogen evolution rate of the optimized 13%CdS/1.3%Au/KTaO3 (13% and 1.3% are the contents of CdS and Au in the composite photocatalyst, respectively) is 2.892 mmol g-1 h-1. Compared to those of bare KTaO3 and CdS, it is approximately 107-fold and 8.5-fold enhanced, respectively. And the sizes of CdS and Au in the photocatalyst are 4.21 and 15.07 nm. The increased photoactivity of the composite can be ascribed to the synergistic effect of several factors, such as: the Au NPs' surface plasma resonance (SPR) impact improves the production of hot electrons and the ability of KTaO3 to capture light; effective integration between CdS QDs and KTaO3 cubes forms a heterojunction and expands the absorption range of KTaO3 in the visible light spectrum, improving the utilization rate of visible light effectively. Hence, a co-modification strategy has been proposed for endowing KTaO3 perovskites with new structures and different functions, and it is expected to become a general strategy to find an illuminating strategy for achieving improvements and enhancements in the photocatalytic field.

Integrated multi-omics reveals the activated retinal microglia with intracellular metabolic reprogramming contributes to inflammation in STZ-induced early diabetic retinopathy.

Diabetic retinopathy (DR) is the leading cause of visual impairment and blindness among working-age people. Inflammation is recognized as a critical driver of the DR process. However, the main retina-specific cell type producing pro-inflammatory cytokines and its mechanism underlying DR are still unclear. Here, we used single-cell sequencing to identify microglia with metabolic pathway alterations that were the main source of IL-1ß in STZ-induced DR mice. To profile the full extent of local metabolic shifts in activated microglia and to reveal the metabolic microenvironment contributing to immune mechanisms, we performed integrated metabolomics, lipidomics, and RNA profiling analyses in microglia cell line samples representative of the DR microenvironment. The results showed that activated microglia with IL-1ß increase exhibited a metabolic bias favoring glycolysis, purine metabolism, and triacylglycerol synthesis, but less Tricarboxylic acid (TCA). In addition, some of these especially glycolysis was necessary to facilitate their pro-inflammation. These findings suggest that activated microglia with intracellular metabolic reprogramming in retina may contribute to pro-inflammation in the early DR.

Ultrathin Niobate Nanosheet Assembly with Au NPs and CdS QDs as a Highly Efficient Photocatalyst.

Niobate nanosheets have aroused widespread interest in recent years for their prospects in catalysis. The exploration of 2D niobate catalysis with stable and efficient properties is still the focus in chemistry and materials science. Herein, the successful fabrication of 2D CdS/Au/HNb3 O8 catalyst is demonstrated which revealed efficient photocatalytic properties in H2 evolution, oxidative self-coupling of amines to imines, and degradation of dyes. Especially the assembled architecture can give a rate of 5.85 mmol ⋅ g-1 ⋅ h-1 of photocatalytic H2 evolution, an ∼254-fold enhancement, compared with bare HNb3 O8 nanosheets under identical conditions. In accordance with density functional theory (DFT) and X-ray adsorption fine structure (XAFS) analyses, the vast improvements are benefited from efficient migration and separation of charge carriers. Besides, the surface plasma resonance (SPR) effect of Au NPs enhances the light harvesting capacity and boosts the generation of hot electrons, efficiently improving the visible-light absorption.

Single cell RNA sequencing (scRNA-Seq) deciphering pathological alterations in streptozotocin-induced diabetic retinas.

Diabetic retinopathy (DR) is an irreversible and progressive diabetic complication leading to visual impairment, even blindness. Due to the delicate and complicated structure of the retina, the pathology of DR has not been completely elucidated yet. We constructed a transcriptome atlas of >14,000 single cells from healthy and streptozotocin (STZ)-induced diabetic murine retinas to decipher pathological alterations of DR. We found four stress-inducible genes Cirbp, Rmb3, Mt1 and Mt2 commonly induced in most types of retinal cells. Bipolar cells were little affected on both number and gene expression. Diabetes increased expression of inflammatory factor genes in retinal microglia, and stimulated expression of immediate early genes (IEGs) in retinal astrocytes. A large number of genes were deregulated in diabetic vascular endothelial cells (ECs), and the differentially expressed genes were paired to the pathways functioning in metabolism, shear stress and vascular permeability. These pathways were mapped by more deregulated genes in a subpopulation of ECs specifically presented in diabetic retinas (diabetic retinal ECs, DRECs). Moreover, several inflammation pathways were activated in DRECs, and the most significant one is the IL-17 signaling pathway. According to the EC markers, DRECs were mainly capillary ECs, confirmed by immunofluorescent staining of S100a9, a target gene of the IL-17 signaling pathway. This study deciphered pathological alterations of DR, and provided clues for potential targets for DR therapy.

CCL24 Protects Renal Function by Controlling Inflammation in Podocytes.

Diabetic nephropathy (DN) is one of the most lethal complications of diabetes mellitus with chronic inflammation. We have examined the role of the inflammatory chemokine CCL24 in DN. We observed that serum levels of CCL24 were significantly elevated in patients with DN. Not only that, the expression of CCL24 was significantly increased in the kidneys of DN mice. The kidney of DN mice showed increased renal fibrosis and inflammation. We characterized an in vitro podocyte cell model with high glucose. Western blot analysis showed that expression of CCL24 was significantly increased under high-glucose conditions. Stimulation with high glucose (35 mmol/L) resulted in an increase in CCL24 expression in the first 48 hours but changed little after 72 hours. Moreover, with glucose stimulation, the level of podocyte fibrosis gradually increased, the expression of the proinflammatory cytokine IL-1ß was upregulated, and the expression of the glucose transporter GLUT4, involved in the insulin signal regulation pathway, also increased. It is suggested that CCL24 is involved in the pathogenesis of DN. In order to study the specific role of CCL24 in this process, we used the CRISPR-Cas9 technique to knock out CCL24 expression in podocytes. Compared with the control group, the podocyte inflammatory response induced by high glucose after CCL24 knockout was significantly increased. These results suggest that CCL24 plays a role in the development of early DN by exerting an anti-inflammatory effect, at least, in podocytes.

The Effects of Sidt2 on the Inflammatory Pathway in Mouse Mesangial Cells.

In patients with chronic kidney disease, the abnormal activation of inflammatory pathways is usually an important factor leading to renal fibrosis and further deterioration of renal function. Finding effective intervention targets of the inflammatory signaling pathway is an important way to treat chronic kidney disease. As a newly discovered lysosomal membrane protein, the correlation between SID1 transmembrane family member 2 (Sidt2) and the inflammatory signaling pathway has not been reported. The aim of this study was to investigate the effect of Sidt2 on inflammation by inhibiting the expression of the Sidt2 gene in a mouse mesangial cell line mediated by a lentiviral CRISPR/Cas9 vector. Hematoxylin and eosin staining and microscopy found that the mesangial cells lost their normal morphology after inhibiting the expression of Sidt2, showing that the cell body became smaller, the edge between the cells was unclear, and part of the nucleus was pyknotic and fragmented, appearing blue-black. The expressions of IKK ß, p-IKK α/ß, NF-κB p65, p-NF-κB p65, p-IκBα, IκBα, and TNF-α in the NF-κB pathway of the Sidt2 -/- group were higher than those of the Sidt2 +/+ group. p-Jak2 and IL6 increased in the Jak/Stat pathway, and p-ERK and p-P38 increased in the MAPK pathway. The expressions of IKK ß, p-IKK α/ß, NF-κB p65, p-NF-κB p65, p-IκBα, IκBα, and TNF-α in the NF-κB pathway of the Sidt2 +/++LPS group were significantly higher than those in the Sidt2 +/+ group. The expressions of IKK ß, p-IKK α/ß, NF-κB p65, p-NF-κB p65, p-IκBα, IκBα, and TNF-α in the Sidt2 -/-+LPS group were higher than those in the Sidt2 -/- group. The expressions of p-IKK α/ß, NF-κB p65, p-NF-κB p65, p-IκBα, IκBα, and TNF-α in the Sidt2 -/-+LPS group were higher than those in the Sidt2 +/++LPS group. In the Jak/Stat pathway, the protein expressions of p-Jak2 and IL6 in the Sidt2 +/++LPS group were higher than those in the Sidt2 +/+ group. The expressions of p-Jak2 and IL6 in the Sidt2 -/-+LPS group were higher than those in the Sidt2 -/- group. The expressions of p-Jak2 and IL6 in the Sidt2 -/-+LPS group were higher than those in the Sidt2 +/++LPS group. The expressions of p-JNK, p-ERK, p-P38, and ERK in the MAPK pathway in the Sidt2 +/++LPS group were higher than those in the Sidt2 +/+ group. The expressions of p-JNK, p-ERK, p-P38, and ERK in the Sidt2 -/-+LPS group were higher than those in the Sidt2 -/- group. The expressions of p-JNK, p-ERK, p-P38, and ERK in the Sidt2 -/-+LPS group were higher than those in the Sidt2 +/++LPS group. These data suggested that deletion of the Sidt2 gene changed the three inflammatory signal pathways, eventually leading to the damage of glomerular mesangial cells in mice.

Deletion of ApoM gene induces apoptosis in mouse kidney via mitochondrial and endoplasmic reticulum stress pathways.

Apolipoprotein M (ApoM) is involved in lipid metabolism, and especially is involved in reverse cholesterol transport. However, the relationship between ApoM and apoptosis has been rarely reported. This study aimed to investigate the effect of ApoM on apoptosis using an ApoM gene-deficient mice (ApoM-/-) model and a mouse mesangial cell model with suppressed ApoM gene expression. First, we observed by transmission electron microscopy that mitochondrial damage and endoplasmic reticulum stress were abnormally altered in the kidneys of ApoM-/- mice compared with wild-type mice, showing mitochondrial swelling, vacuolization, myeloid changes, and expansion of the rough endoplasmic reticulum. At the molecular level, the expression of pro-apoptotic related proteins such as AIF, Bax, chop, clever-caspase 3, clever-caspase 7, clever-caspase 9, and clever-caspase 12 increased, and the expression of anti-apoptotic protein Bcl-2 decreased. Secondly, by interfering with the expression of the ApoM gene in mouse mesangial cells, we found that, compared with the control group (NC-si), the cells of the experimental group (siApoM) showed decreased cell viability, nuclear chromatin condensation, nuclear lysis, and an increased proportion of early apoptotic cells. The results in cells at the molecular level were consistent with those at the tissue level. These data indicated that the deletion of the ApoM gene led to upregulation of apoptosis in mouse kidney tissues and mesangial cells through the mitochondrial and endoplasmic reticulum pathways.