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Introduction Heart failure is the clinical manifestation of a heterogeneous group of often overlapping conditions that impair the effective emptying or filling of the cardiac ventricles. Despite the heterogeneity of [...], Inflammation promotes adverse ventricular remodeling, a common antecedent of heart failure. Here, we set out to determine how inflammatory cells affect cardiomyocytes in the remodeling heart. Pathogenic cardiac macrophages induced an IFN response in cardiomyocytes, characterized by upregulation of the ubiquitin-like protein IFN-stimulated gene 15 (ISG15), which posttranslationally modifies its targets through a process termed ISGylation. Cardiac ISG15 is controlled by type I IFN signaling, and ISG15 or ISGylation is upregulated in mice with transverse aortic constriction or infused with angiotensin II; rats with uninephrectomy and DOCA-salt, or pulmonary artery banding; cardiomyocytes exposed to IFNs or CD4* T cell-conditioned medium; and ventricular tissue of humans with nonischemic cardiomyopathy. By nanoscale liquid chromatography-tandem mass spectrometry, we identified the myofibrillar protein filamin-C as an ISGylation target. ISG15 deficiency preserved cardiac function in mice with transverse aortic constriction and led to improved recovery of mouse hearts ex vivo. Metabolomics revealed that ISG15 regulates cardiac amino acid metabolism, whereas ISG15 deficiency prevented misfolded filamin-C accumulation and induced cardiomyocyte autophagy. In sum, ISG15 upregulation is a feature of pathological ventricular remodeling, and protein ISGylation is an inflammation-induced posttranslational modification that may contribute to heart failure development by altering cardiomyocyte protein turnover.

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have emerged as pivotal medications for heart failure, demonstrating remarkable cardiovascular benefits extending beyond their glucose-lowering effects. The unexpected cardiovascular advantages have intrigued and prompted the scientific community to delve into the mechanistic underpinnings of these novel actions. Preclinical studies have generated many mechanistic theories, ranging from their renal and extrarenal effects to potential direct actions on cardiac muscle cells, to elucidate the mechanisms linking these drugs to clinical cardiovascular outcomes. Despite the strengths and limitations of each theory, many await validation in human studies. Furthermore, whether SGLT2 inhibitors confer therapeutic benefits in specific subsets of cardiomyopathies akin to their efficacy in other heart failure populations remains unclear. By examining the shared pathological features between heart failure resulting from vascular diseases and other causes of cardiomyopathy, certain specific molecular actions of SGLT2 inhibitors (particularly those targeting cardiomyocytes) would support the concept that these medications will yield therapeutic benefits across a broad range of cardiomyopathies. This article aims to discuss the important mechanisms of SGLT2 inhibitors and their implications in hypertrophic and dilated cardiomyopathies. Furthermore, we offer insights into future research directions for SGLT2 inhibitor studies, which hold the potential to further elucidate the proposed biological mechanisms in greater detail. [ABSTRACT FROM AUTHOR]

This document is a summary of a special issue of the International Journal of Molecular Sciences titled "Latest Advances in Nanomedicine Strategies for Different Diseases." The issue focuses on the use of nanotherapeutic formulations for delivering mRNA vaccines for diseases such as SARS-CoV-2. It also highlights advancements in nanomedicine for the treatment of various diseases, including cancer. The articles in the issue discuss innovative methods for creating nanoformulations that can target specific areas while minimizing toxicity. Topics covered include gene therapies for neurological diseases, nanoformulations for enhancing the effectiveness of cancer chemotherapy, and the use of nanotheranostics for simultaneous diagnosis and treatment. The authors hope that the research presented in this special issue will guide future studies in developing improved nanotherapeutics. [Extracted from the article]

Background and Purpose: Activated fibroblasts deposit fibrotic matrix in chronic kidney disease (CKD) and G‐protein coupled receptors (GPCRs) are the most druggable therapeutic targets. Here, we set out to establish a transcriptional profile that identifies activated kidney fibroblasts and the GPCRs that they express. Experimental Approach: RNA sequencing and single cell qRT‐PCR were performed on mouse kidneys after unilateral ureteral obstruction (UUO). Candidate expression was evaluated in mice with UUO or diabetes or injected with adriamycin or folic acid. Intervention studies were conducted in mice with diabetes or UUO. Correlative histology was performed in human kidney tissue. Key Results: Transcription factor 21 (Tcf21)+ cells that expressed 2 or 3 of Postn, Acta2 and Pdgfra were highly enriched for fibrogenic genes and were defined as activated kidney fibroblasts. Tcf21+ α‐smooth muscle actin (α‐SMA)+ interstitial cells accumulated in kidneys of mice with UUO or diabetes or injected with adriamycin or folic acid, whereas renin‐angiotensin system blockade attenuated increases in Tcf21 in diabetic mice. Fifty‐six GPCRs were up‐regulated in single Tcf21+ kidney fibroblasts, the most up‐regulated being Adgra2 and S1pr3. Adenosine receptors, Adora2a/2b, were up‐regulated in Tcf21+ fibroblasts and the adenosine receptor antagonist, caffeine decreased Tcf21 upregulation and kidney fibrosis in UUO mice. TCF21, ADGRA2, S1PR3 and ADORA2A/2B were each detectable in α‐SMA+ interstitial cells in human kidney samples. Conclusion and Implications: Tcf21 is a marker of kidney fibroblasts that are enriched for fibrogenic genes in CKD. Further analysis of the GPCRs expressed by these cells may identify new targets for treating CKD. LINKED ARTICLES: This article is part of a themed issue on Translational Advances in Fibrosis as a Therapeutic Target. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v180.22/issuetoc [ABSTRACT FROM AUTHOR]

The causes of the increased risk of severe coronavirus disease 2019 (COVID-19) in people with diabetes are unclear. It has been speculated that renin-angiotensin system (RAS) blockers may promote COVID-19 by increasing ACE2, which severe acute respiratory syndrome coronavirus 2 uses to enter host cells, along with the host protease TMPRSS2. Taking a reverse translational approach and by combining in situ hybridization, primary cell isolation, immunoblotting, quantitative RT-PCR, and liquid chromatography-tandem mass spectrometry, we studied lung and kidney ACE2 and TMPRSS2 in diabetic mice mimicking host factors linked to severe COVID-19. In healthy young mice, neither the ACE inhibitor ramipril nor the AT1 receptor blocker telmisartan affected lung or kidney ACE2 or TMPRSS2, except for a small increase in kidney ACE2 protein with ramipril. In contrast, mice with comorbid diabetes (aging, high-fat diet, and streptozotocin-induced diabetes) had heightened lung ACE2 and TMPRSS2 protein levels and increased lung ACE2 activity. None of these parameters were affected by RAS blockade. ACE2 was similarly upregulated in the kidneys of mice with comorbid diabetes compared with aged controls, whereas TMPRSS2 (primarily distal nephron) was highest in telmisartan-treated animals. Upregulation of lung ACE2 activity in comorbid diabetes may contribute to an increased risk of severe COVID-19. This upregulation is driven by comorbidity and not by RAS blockade. [ABSTRACT FROM AUTHOR]

Blood glucose-lowering therapies can positively or negatively affect heart function in type 2 diabetes, or they can have neutral effects. Dipeptidyl peptidase 4 (DPP-4) inhibitors lower blood glucose by preventing the proteolytic inactivation of glucagon-like peptide 1 (GLP-1). However, GLP-1 is not the only peptide substrate of DPP-4. Here, we investigated the GLP-1-independent cardiac effects of DPP-4 substrates. Pointing to GLP-1 receptor (GLP-1R)-independent actions, DPP-4 inhibition prevented systolic dysfunction equally in pressure-overloaded wild-type and GLP-1R knockout mice. Likewise, DPP-4 inhibition or the DPP-4 substrates substance P or C-X-C motif chemokine ligand 12 (CXCL12) improved contractile recovery after no-flow ischemia in the hearts of otherwise healthy young adult mice. Either DPP-4 inhibition or CXCL12 increased phosphorylation of the Ca2+ regulatory protein phospholamban (PLN), and CXCL12 directly enhanced cardiomyocyte Ca2+ flux. In contrast, hearts of aged obese diabetic mice (which may better mimic the comorbid patient population) had diminished levels of PLN phosphorylation. In this setting, CXCL12 paradoxically impaired cardiac contractility in a phosphoinositide 3-kinase γ-dependent manner. These findings indicate that the cardiac effects of DPP-4 inhibition primarily occur through GLP-1R-independent processes and that ostensibly beneficial DPP-4 substrates can paradoxically worsen heart function in the presence of comorbid diabetes. [ABSTRACT FROM AUTHOR]

Abstract: Morin, a bioflavonoid with diverse pharmacological effects against various diseases; in most cases morin protective effects were attributed to its detoxifying effect against reactive oxygen species (ROS). Diabetic neuropathy (DN) is a chronic, debilitating neuronal pain associated with intense generation of free radicals and proinflammatory cytokine accumulation in peripheral neurons. We investigated the pharmacological effect of morin against metabolic excess mediated mitochondrial ROS generation and corresponding effect on Nrf2, NF‐κB pathways in Streptozotocin (STZ)‐induced diabetic rats and in high glucose insulted Mouse neuroblastoma cell line, Neuro 2A (N2A). Animals were evaluated for nerve function parameters, motor and sensory nerve conduction velocities (MNCV and SNCV) and nerve blood flow (NBF) followed by TUNEL and immunoblot analysis. Mitochondrial function was evaluated by performing JC‐1 and MitoSOX assays in high glucose (30 mM) incubated N2A cells. Diabetic animals showed significant impairment in MNCV, SNCV, and NBF as well as increased pain hypersensitivity. However, oral administration of morin at 50 and 100 mg/kg improved SNCV, MNCV, and NBF and reduced sensorimotor alterations (hyperalgesia and allodynia) in diabetic animals. Studies in N2A cells have revealed that morin ameliorated the high glucose‐induced mitochondrial superoxide production, membrane depolarization, and total ROS generation. Morin effectively counteracted NF‐κB‐mediated neuroinflammation by reducing ROS mediated IKK activation and increased Nrf2‐mediated antioxidant defenses in high glucose‐induced N2A cells. The results of our study suggest that morin has exquisite role in offering neuroprotection in experimental DN and further clinical investigation may reward in finding better alternative for the management of DN. © 2017 BioFactors, 44(2):109–122, 2018 [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Mitochondrial Hormesis and Diabetic Complications" published in the journal in 2015.

Background: Diabetic nephropathy (DN) is a chronic hyperglycemic manifestation of microvascular damage in the kidneys. Widespread research in this area suggests the involvement of perturbed redox homeostasis and autophagy in renal cells phrase- promote the progression of DN., Materials and Methods: Reframed sentences-The present study investigates the pharmacological effect of Syringic acid (SYA), in streptozotocin (STZ, 55 mg/kg, i.p) induced diabetic nephropathy model and in high glucose (30 mM) challenged rat renal epithelial cells (NRK 52E) cells with a focus on oxidative stress and autophagy mechanisms., Results: Both in vivo and in vitro experimental data revealed elevated oxidative stress markers along with compromised levels of nuclear factor erythroid 2-related factor 2 (Nrf2), a pivotal cellular redox-regulated transcription factor in renal cells upon glycemic stress. Elevated blood glucose also reduced the autophagy process as indicated by low expression of light chain (LC) 3-IIB in diabetic kidney and in NRK 52E cells subjected to excess glucose. SYA (25 and 50 mg/kg, p.o.) administration for 4 weeks to diabetic rats, Reframed sentence-preserved the renal function as evidenced by reduced serum creatinine levels as well as improved urine creatinine and urea levles as compared to non treated diabetic animals. At the molecular level, SYA improved renal expression of Nrf2 and autophagy-related proteins (Atg5, Atg3, and Atg7) in diabetic rats. Similarly, SYA (10 and 20 μM) co-treatment in high glucose-treated NRK 52E cells displayed increased levels of Nrf2 and autophagy induction., Conclusion: Results from this study signify the renoprotective effect of SYA and highlight the modulation of oxidative stress and autophagy mechanisms to mitigate diabetic kidney disease., Competing Interests: None