Telmisartan Mitigates High-Glucose-Induced Injury in Renal Glomerular Endothelial Cells (rGECs) and Albuminuria in Diabetes Mice

A glucose-responsive alginate-based hydrogel laden with modified GLP-1 and telmisartan ameliorates type 2 diabetes and reduces liver and kidney toxicities

The pathophysiology associated with type 2 diabetes mellitus (T2DM) includes insulin resistance, increased oxidative stress, a pro-inflammatory macrophage population, and dysfunction of pancreatic β cells in the islets of Langerhans, along with hepato- and nephro-toxicity. In this study, an injectable glucose-responsive hydrogel (Diabogel) was developed using alginate and 3-aminophenyl boronic acid to deliver modified glucagon-like peptide-1, insulinoma cell-derived extracellular vesicles, and telmisartan. Diabogel demonstrated cytocompatibility, decreased reactive oxygen species, enhanced insulin synthesis, and improved glucose uptake in vitro. In a high-fat diet/streptozotocin-induced murine model of T2DM, Diabogel lowered blood glucose levels, maintained body weight, and increased insulin expression. Furthermore, it promoted an anti-inflammatory microenvironment in the pancreas by regulating macrophage phenotype and the expression of NF-κB, supported cellular proliferation, and restored the pancreatic islets. In addition, Diabogel treatment significantly lowered the serum levels of pro-inflammatory cytokines and enhanced anti-inflammatory cytokines. Interestingly, Diabogel treatment also lowered diabetes-associated hepato- and nephro-toxicity. Taken together, Diabogel may serve as a potential approach for the treatment of T2DM, regulating blood glucose levels, restoring pancreatic β cell function, and reducing hepatic and renal toxicities.

Telmisartan loading thermosensitive hydrogel repairs gut epithelial barrier for alleviating inflammatory bowel disease

Inflammatory bowel disease (IBD) remains a global health concern with a complex and incompletely understood pathogenesis. In the course of IBD development, damage to intestinal epithelial cells and a reduction in the expression of tight junction (TJ) proteins compromise the integrity of the intestinal barrier, exacerbating inflammation. Notably, the renin-angiotensin system and angiotensin II receptor type 1 (AT1R) play a crucial role in regulating the pathological progression including vascular permeability, and immune microenvironment. Thus, Telmisartan (Tel), an AT1R inhibitor, loading thermosensitive hydrogel was constructed to investigate the potential of alleviating inflammatory bowel disease through rectal administration. The constructed hydrogel exhibits an advantageous property of rapid transformation from a solution to a gel state at 37°C, facilitating prolonged drug retention within the gut while mitigating irritation associated with rectal administration. Results indicate that Tel also exhibits a beneficial effect in ameliorating colon shortening, colon wall thickening, cup cell lacking, crypt disappearance, and inflammatory cell infiltration into the mucosa in colitis mice. Moreover, it significantly upregulates the expression of TJ proteins in colonic tissues thereby repairing the intestinal barrier damage and alleviating the ulcerative colitis (UC) disease process. In conclusion, Tel-loaded hydrogel demonstrates substantial promise as a potential treatment modality for IBD.

Molecular mechanism of GSDMD mediated glomerular endothelial cells pyroptosis: An implying in the progression of diabetic nephropathy

Diabetic nephropathy (DN), a chronic progressive kidney disease, is the most prevalent microvascular complication associated with diabetes which causes the end-stage renal disease. Glomerular endothelial cells (GECs) are one of the inherent cells of the glomerulus and are particularly susceptible to be damaged by glucose, lipids and inflammatory factors. Numerous studies indicated that GECs injury was a critical pathological event in the early stages of DN. Previous studies have shown that podocyte pyroptosis occurred through the classical caspase-1 pathway, leading to kidney injury. However, the occurrence of pyroptosis in GECs and the underlying mechanism remain unclear. In this study, we investigated the pyroptosis of GECs during DN and its underlying mechanism. Upon stimulation with high glucose (HG), we observed the upregulation of GSDMD and cleaved N-terminus, disruption of cell membrane integrity, and an increase in IL-18 inflammatory cytokines. Also, we found that the expression of caspase-11, GSDMD and GSDMD-N were increased in C57BL/6J mice induced by STZ combined with high sugar and fat. In addition, the pathological results of kidney showed a significant thickening of the glomerular basement membrane, abnormal increasement of extracellular matrix and hyperplasia with blurred boundaries of glomerulus. Furthermore, interfering the expression of GSDMD improved the pathological degree of kidney. These findings indicated that the pyroptosis of GECs during DN was facilitated by the non-classical pathway of caspase-11/GSDMD, ultimately leading to GECs injury and further aggravating the progression of DN. This work highlights the potential of GSDMD as a therapeutic target for the treatment of DN.

MYOSIN LIGHT CHAIN KINASE DELETION WORSENS LUNG PERMEABILITY AND INCREASES MORTALITY IN PNEUMONIA-INDUCED SEPSIS

ABSTRACT

Increased epithelial permeability in sepsis is mediated via disruptions in tight junctions, which are closely associated with the perijunctional actin-myosin ring. Genetic deletion of myosin light chain kinase (MLCK) reverses sepsis-induced intestinal hyperpermeability and improves survival in a murine model of intra-abdominal sepsis. In an attempt to determine the generalizability of these findings, this study measured the impact of MLCK deletion on survival and potential associated mechanisms following pneumonia-induced sepsis. MLCK -/- and wild-type mice underwent intratracheal injection of Pseudomonas aeruginosa . Unexpectedly, survival was significantly worse in MLCK -/- mice than wild-type mice. This was associated with increased permeability to Evans blue dye in bronchoalveolar lavage fluid but not in tissue homogenate, suggesting increased alveolar epithelial leak. In addition, bacterial burden was increased in bronchoalveolar lavage fluid. Cytokine array using whole-lung homogenate demonstrated increases in multiple proinflammatory and anti-inflammatory cytokines in knockout mice. These local pulmonary changes were associated with systemic inflammation with increased serum levels of IL-6 and IL-10 and a marked increase in bacteremia in MLCK -/- mice. Increased numbers of both bulk and memory CD4 + T cells were identified in the spleens of knockout mice, with increased early and late activation. These results demonstrate that genetic deletion of MLCK unexpectedly increases mortality in pulmonary sepsis, associated with worsened alveolar epithelial leak and both local and systemic inflammation. This suggests that caution is required in targeting MLCK for therapeutic gain in sepsis.

Cellular mechanism of action of forsythiaside for the treatment of diabetic kidney disease

Background: Diabetic kidney disease (DKD) becomes the leading cause of death for end-stage renal disease, whereas the potential mechanism is unclear and effective therapy is still rare. Our study was designed to investigate the cellular mechanism of Forsythiaside against DKD. Materials and Methods: The targets of Forsythiaside and the DKD-related targets were obtained from databases. The overlapping targets in these two sets were regarded as potential targets for alleviation of DKD by Forsythiaside. The targets of diabetic podocytopathy and tubulopathy were also detected to clarify the mechanism of Forsythiaside ameliorating DKD from the cellular level. Results: Our results explored that PRKCA and RHOA were regarded as key therapeutic targets of Forsythiaside with excellent binding affinity for treating DKD podocytopathy. Enrichment analysis suggested the underlying mechanism was mainly focused on the oxidative stress and mTOR signaling pathway. The alleviated effects of Forsythiaside on the reactive oxidative species accumulation and PRKCA and RHOA proteins upregulation in podocytes were also confirmed. Conclusion: The present study elucidates that Forsythiaside exerts potential treatment against DKD which may act directly RHOA and PRKCA target by suppressing the oxidative stress pathway in podocytes. And Forsythiaside could be regarded as one of the candidate drugs dealing with DKD in future experimental or clinical researches.

The impact of oxidative stress-induced mitochondrial dysfunction on diabetic microvascular complications

Diabetes mellitus (DM) is a metabolic disease characterized by chronic hyperglycaemia, with absolute insulin deficiency or insulin resistance as the main cause, and causes damage to various target organs including the heart, kidney and neurovascular. In terms of the pathological and physiological mechanisms of DM, oxidative stress is one of the main mechanisms leading to DM and is an important link between DM and its complications. Oxidative stress is a pathological phenomenon resulting from an imbalance between the production of free radicals and the scavenging of antioxidant systems. The main site of reactive oxygen species (ROS) production is the mitochondria, which are also the main organelles damaged. In a chronic high glucose environment, impaired electron transport chain within the mitochondria leads to the production of ROS, prompts increased proton leakage and altered mitochondrial membrane potential (MMP), which in turn releases cytochrome c (cyt-c), leading to apoptosis. This subsequently leads to a vicious cycle of impaired clearance by the body's antioxidant system, impaired transcription and protein synthesis of mitochondrial DNA (mtDNA), which is responsible for encoding mitochondrial proteins, and impaired DNA repair systems, contributing to mitochondrial dysfunction. This paper reviews the dysfunction of mitochondria in the environment of high glucose induced oxidative stress in the DM model, and looks forward to providing a new treatment plan for oxidative stress based on mitochondrial dysfunction.

Mitochondrial Effects of Common Cardiovascular Medications: The Good, the Bad and the Mixed

Mitochondria are central organelles in the homeostasis of the cardiovascular system via the integration of several physiological processes, such as ATP generation via oxidative phosphorylation, synthesis/exchange of metabolites, calcium sequestration, reactive oxygen species (ROS) production/buffering and control of cellular survival/death. Mitochondrial impairment has been widely recognized as a central pathomechanism of almost all cardiovascular diseases, rendering these organelles important therapeutic targets. Mitochondrial dysfunction has been reported to occur in the setting of drug-induced toxicity in several tissues and organs, including the heart. Members of the drug classes currently used in the therapeutics of cardiovascular pathologies have been reported to both support and undermine mitochondrial function. For the latter case, mitochondrial toxicity is the consequence of drug interference (direct or off-target effects) with mitochondrial respiration/energy conversion, DNA replication, ROS production and detoxification, cell death signaling and mitochondrial dynamics. The present narrative review aims to summarize the beneficial and deleterious mitochondrial effects of common cardiovascular medications as described in various experimental models and identify those for which evidence for both types of effects is available in the literature.

Bibliometric Study of Trends in the Diabetic Nephropathy Research Space from 2016 to 2020

Background

Diabetic nephropathy (DN) is one of the most common microvascular complications of diabetes mellitus (DM), but no bibliometric studies pertaining to DN have been published within the last 5 years.

Objectives

Most prior studies have focused on specific problems in the DN field. This study attempts to sort out and visualize the knowledge framework in this research space from a holistic and highly generalized perspective. Readers can quickly understand and master the knowledge regarding DN research conducted from 2016 to 2020, in addition to predicting future research hotspots and possible directions for development in this field in a comprehensive and scientifically valid manner.

Methods

Literature information, discourse matrices, and co-occurrence matrices were generated using BICOMB. gCLUTO was used for biclustering analyses and visualization. Strategic diagrams were generated using GraphPad Prism 5. The social network analysis (SNA) was analyzed and plotted using Ucinet 6.0 and Netdraw.

Results

In total, 55 high-frequency MeSH terms/MeSH subheadings were selected and grouped into 5 clusters in a biclustering analysis. These analyses revealed that extensive studies of the etiology, diagnosis, and treatment of DN have been conducted over the last 5 years, while further research regarding DN-related single nucleotide polymorphisms, miRNAs, and signal transduction are warranted as these research areas remain relatively immature.

Conclusion

Together, these results outline a robust knowledge structure pertaining to the field of DN-related research over the last 5 years, providing a valuable resource for readers by enabling the easy comprehension of relevant information. In addition, this analysis highlights predicted DN-related research directions and hotspots.