Targeting mir128-3p alleviates myocardial insulin resistance and prevents ischemia-induced heart failure

Bone and Extracellular Signal-Related Kinase 5 (ERK5)

Bones are vital for anchoring muscles, tendons, and ligaments, serving as a fundamental element of the human skeletal structure. However, our understanding of bone development mechanisms and the maintenance of bone homeostasis is still limited. Extracellular signal-related kinase 5 (ERK5), a recently identified member of the mitogen-activated protein kinase (MAPK) family, plays a critical role in the pathogenesis and progression of various diseases, especially neoplasms. Recent studies have highlighted ERK5's significant role in both bone development and bone-associated pathologies. This review offers a detailed examination of the latest research on ERK5 in different tissues and diseases, with a particular focus on its implications for bone health. It also examines therapeutic strategies and future research avenues targeting ERK5.

Profile of serum microRNAs in heart failure with reduced and preserved ejection fraction: Correlation with myocardial remodeling

Background and aims

Cardiomyocyte hypertrophy and interstitial fibrosis are key components of myocardial remodeling in Heart Failure (HF) with preserved (HFpEF) or reduced ejection fraction (HFrEF). MicroRNAs (miRNAs) are non-coding, evolutionarily conserved RNA molecules that may offer novel insights into myocardial remodeling. This study aimed to characterize miRNA expression in HFpEF (LVEF ≥  45%) and HFrEF (LVEF < 45%) and its association with myocardial remodeling.

Methods

Prospectively enrolled symptomatic HF patients (HFpEF:n = 36; HFrEF:n = 31) and controls (n = 23) underwent cardiac magnetic resonance imaging with T1-mapping and circulating miRNA expression (OpenArray system).

Results

13 of 188 miRNAs were differentially expressed between HF groups (11 downregulated in HFpEF). Myocardial extracellular volume (ECV) was increased in both HF groups (HFpEF 30 ± 5%; HFrEF 30 ± 3%; controls 26 ± 2%, p < 0.001). miR-128a-3p, linked to cardiac hypertrophy, fibrosis, and dysfunction, correlated positively with ECV in HFpEF (r = 0.60, p = 0.01) and negatively in HFrEF (r = - 0.51, p = 0.04). miR-423-5p overexpression, previously associated HF mortality, was inversely associated with LVEF (r = - 0.29, p = 0.04) and intracellular water lifetime (τ ic) (r = - 0.45, p < 0.05) in both HF groups, and with NT-proBNP in HFpEF (r = - 0.63, p < 0.01).

Conclusions

miRNA expression profiles differed between HF phenotypes. The differential expression and association of miR-128a-3p with ECV may reflect the distinct vascular, interstitial, and cellular etiologies of HF phenotypes.

Driving force of deteriorated cellular environment in heart failure: Metabolic remodeling

Heart Failure (HF) has been one of the leading causes of death worldwide. Though its latent mechanism and therapeutic manipulation are updated and developed ceaselessly, there remain great gaps in the cognition of heart failure. High morbidity and readmission rates among HF patients are waiting to be addressed. Recent studies have found that myocardial energy metabolism was closely related to heart failure, in which substrate utilization, as well as intermediate metabolism disorders, insulin resistance, oxidative stress, and mitochondrial dysfunction, might underlie systolic dysfunction and progression of HF. This article centers on the changes and counteraction of cardiac energy metabolism in the failing heart. Therefore, targeting impaired energy provision is of great potential in the treatment of HF. And shifting the objective from traditional neurohormones to improving the cellular environment is expected to further optimize the management of HF.

MiRNA dysregulation underlying common pathways in type 2 diabetes and cancer development: an Italian Association of Medical Oncology (AIOM)/Italian Association of Medical Diabetologists (AMD)/Italian Society of Diabetology (SID)/Italian Society of Endocrinology (SIE)/Italian Society of Pharmacology (SIF) multidisciplinary critical view

Increasing evidence suggests that patients with diabetes, particularly type 2 diabetes (T2D), are characterized by an increased risk of developing different types of cancer, so cancer could be proposed as a new T2D-related complication. On the other hand, cancer may also increase the risk of developing new-onset diabetes, mainly caused by anticancer therapies. Hyperinsulinemia, hyperglycemia, and chronic inflammation typical of T2D could represent possible mechanisms involved in cancer development in diabetic patients. MicroRNAs (miRNAs) are a subset of non-coding RNAs, ⁓22 nucleotides in length, which control the post-transcriptional regulation of gene expression through both translational repression and messenger RNA degradation. Of note, miRNAs have multiple target genes and alteration of their expression has been reported in multiple diseases, including T2D and cancer. Accordingly, specific miRNA-regulated pathways are involved in the pathogenesis of both conditions. In this review, a panel of experts from the Italian Association of Medical Oncology (AIOM), Italian Association of Medical Diabetologists (AMD), Italian Society of Diabetology (SID), Italian Society of Endocrinology (SIE), and Italian Society of Pharmacology (SIF) provide a critical view of the evidence about the involvement of miRNAs in the pathophysiology of both T2D and cancer, trying to identify the shared miRNA signature and pathways able to explain the strong correlation between the two conditions, as well as to envision new common pharmacological approaches.

FGF21/FGFR1-β-KL cascade in cardiomyocytes modulates angiogenesis and inflammation under metabolic stress

Diabetes is a metabolic disorder with an increased risk of developing heart failure. Inflammation and damaged vasculature are the cardinal features of diabetes-induced cardiac damage. Moreover, systemic metabolic stress triggers discordant intercellular communication, thus culminating in cardiac dysfunction. Fibroblast growth factor 21 (FGF21) is a pleiotropic hormone transducing cellular signals via fibroblast growth factor receptor 1 (FGFR1) and its co-receptor beta-klotho (β-KL). This study first demonstrated a decreased expression or activity of FGFR1 and β-KL in both human and mouse diabetic hearts. Reinforcing cardiac FGFR1 and β-KL expression can alleviate pro-inflammatory response and endothelial dysfunction upon diabetic stress. Using proteomics, novel cardiomyocyte-derived anti-inflammatory and proangiogenic factors regulated by FGFR1-β-KL signaling were identified. Although not exhaustive, this study provides a unique insight into the protective topology of the cardiac FGFR1-β-KL signaling-mediated intercellular reactions in the heart in response to metabolic stress.

Empagliflozin mediated miR-128-3p upregulation promotes differentiation of hypoxic cancer stem-like cells in breast cancer

AIMS

The hsa-miR-128-3p expression is downregulated in advanced breast cancer patients. Empagliflozin (EMPA) is an anti-diabetic drug with anticancer potential. The present study investigated the effect of EMPA on cancer cell differentiation by acting as a miR-128-3p mimicking drug in breast cancer.

MAIN METHODS

Our results first demonstrate SP1 and PKM2 as the downstream effectors of hsa-miR-128-3p. Further, transfection with siPKM2, miR-128-3p mimics, and inhibitors was performed to assess their involvement in cancer stemness using flow cytometry. Further, EMPA as miR-128-3p mimicking drug was screened and explored on cancer cell differentiation. Then, we treated the 4T1-Red-FLuc allograft breast tumor with EMPA to assess its inhibitory potential toward tumor growth using IVIS® Spectrum. Immunohistochemistry was performed to evaluate cancer cell differentiation and cell proliferation.

KEY FINDINGS

We found that hsa-miR-128-3p is the upstream regulator of SP1 and PKM2 in hypoxic breast cancer cells. Overexpression of miR-128-3p with mimics downregulate SP1 and PKM2, whereas miR-128-3p inhibitor shows an opposite effect. The enhanced expression of miR-128-3p and PKM2 knockdown diminishes hypoxia-induced CD44 expression and enhance CD44⁺/CD24⁺ differentiated cells. We also identified EMPA as the miR-128-3p mimicking drug that can enhance the differentiated cell population. Further, EMPA suppressed in vivo tumor growth, lung metastasis, tumor bioluminescence, and cell proliferation. Therefore, EMPA abrogates breast cancer stemness by inactivating SP1 and PKM2 via enhanced miR-128-3p expression.

SIGNIFICANCE

EMPA could be a promising drug in combination with other chemotherapeutic drugs in advanced breast cancer.

Independent effects of the triglyceride-glucose index on all-cause mortality in critically ill patients with coronary heart disease: analysis of the MIMIC-III database

BACKGROUND

The triglyceride-glucose (TyG) index is a reliable alternative biomarker of insulin resistance (IR). However, whether the TyG index has prognostic value in critically ill patients with coronary heart disease (CHD) remains unclear.

METHODS

Participants from the Medical Information Mart for Intensive Care III (MIMIC-III) were grouped into quartiles according to the TyG index. The primary outcome was in-hospital all-cause mortality. Cox proportional hazards models were constructed to examine the association between TyG index and all-cause mortality in critically ill patients with CHD. A restricted cubic splines model was used to examine the associations between the TyG index and outcomes.

RESULTS

A total of 1,618 patients (65.14% men) were included. The hospital mortality and intensive care unit (ICU) mortality rate were 9.64% and 7.60%, respectively. Multivariable Cox proportional hazards analyses indicated that the TyG index was independently associated with an elevated risk of hospital mortality (HR, 1.71 [95% CI 1.25-2.33] P = 0.001) and ICU mortality (HR, 1.50 [95% CI 1.07-2.10] P = 0.019). The restricted cubic splines regression model revealed that the risk of hospital mortality and ICU mortality increased linearly with increasing TyG index (P for non-linearity = 0.467 and P for non-linearity = 0.764).

CONCLUSIONS

The TyG index was a strong independent predictor of greater mortality in critically ill patients with CHD. Larger prospective studies are required to confirm these findings.

Correlation analysis of the triglyceride glucose index and heart failure with preserved ejection fraction in essential hypertensive patients

BACKGROUND

Triglyceride glucose index (TyG index) is a novel marker of insulin resistance. Studies have shown that TyG index is closely associated with the occurrence of hypertension and cardiovascular disease. However, little is known about the correlation between TyG index and the occurrence of heart failure with preserved ejection fraction (HFpEF) in hypertensive patients.

HYPOTHESIS

Our study assumes that TyG index strongly correlates with occurence of HFpEF in hypertensive patients.

METHODS

This research enrolled 559 hypertensive patients (273 patients with HFpEF and 286 without HFpEF) admitted to the Department of Cardiology of Jiading Branch of Shanghai General Hospital from 2020 to 2021 as the study subjects. Gender, age, diastolic blood pressure, systolic blood pressure (SBP), and heart rate (HR) were recorded at admission. Medication history and fasting blood samples were harvested after admission to detect laboratory index. Cardiac function and ventricular structure index were measured by echocardiography. Pearson correlation analysis was conducted to identify the correlation of TyG index with cardiac function and ventricular structure. The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value of TyG index in HFpEF with hypertension.

RESULTS

HFpEF patients had higher diuretic use frequencies, fasting plasma glucose, NT-proBNP, triglycerides, TyG index, left atrial diameter (LAD), left ventricular mass index (LVMI), the ratio of peak E-velocity of mitral orifice to peak velocity of early diastolic mitral annulus (E/e'), and SBP but lower ratio of peak E of early diastolic maximum blood flow velocity to peak A of late diastolic maximum blood flow velocity of mitral orifice (E/A) and average e' than non-HFpEF patients. Moreover, TyG index was correlated with LAD, left ventricular ejection fraction (LVEF), LVMI, average e', E/e', and NT-proBNP. The multivariate regression analysis suggested that TyG index, E/e', and NT-proBNP were independent risk factors for HFpEF in hypertensive patients. Compared with E/e' and NT-proBNP, the area under the ROC curve (0.778 [95% confidence interval: 0.707-0.849]) was the largest for TyG index.

CONCLUSION

TyG index is higher in HFpEF patients than in non-HFpEF patients and related to cardiac diastolic function, which strongly correlates with occurrence of HFpEF in hypertensive patients.

Paracrine signal emanating from stressed cardiomyocytes aggravates inflammatory microenvironment in diabetic cardiomyopathy

Myocardial inflammation contributes to cardiomyopathy in diabetic patients through incompletely defined underlying mechanisms. In both human and time-course experimental samples, diabetic hearts exhibited abnormal ER, with a maladaptive shift over time in rodents. Furthermore, as a cardiac ER dysfunction model, mice with cardiac-specific p21-activated kinase 2 (PAK2) deletion exhibited heightened myocardial inflammatory response in diabetes. Mechanistically, maladaptive ER stress-induced CCAAT/enhancer-binding protein homologous protein (CHOP) is a novel transcriptional regulator of cardiac high-mobility group box-1 (HMGB1). Cardiac stress-induced release of HMGB1 facilitates M1 macrophage polarization, aggravating myocardial inflammation. Therapeutically, sequestering the extracellular HMGB1 using glycyrrhizin conferred cardioprotection through its anti-inflammatory action. Our findings also indicated that an intact cardiac ER function and protective effects of the antidiabetic drug interdependently attenuated the cardiac inflammation-induced dysfunction. Collectively, we introduce an ER stress-mediated cardiomyocyte-macrophage link, altering the macrophage response, thereby providing insight into therapeutic prospects for diabetes-associated cardiac dysfunction.

Upregulation of miR-128 Mediates Heart Injury by Activating Wnt/β-catenin Signaling Pathway in Heart Failure Mice

Cardiac hypertrophy contributes to heart failure and is pathogenically modulated by a network of signaling cascades including Wnt/β-catenin signaling pathway. miRNAs have been widely demonstrated to regulate gene expression in heart development. miR-128 was routinely found as a brain-enriched gene and has been functionally associated with regulation of cardiac function. However, its role and molecular mechanisms that regulate cardiac hypertrophy remain largely unclear. Adeno-associated virus serotype 9 (AAV9)-mediated constructs with miR-128 or anti-miR-128 were generated and delivered to overexpression or blockade of miR-128 in vivo followed by HF induction with isoproterenol (ISO) or transverse aortic constriction (TAC). Cardiac dysfunction and hypertrophy, coupled with involved gene and protein level, were then assessed. Our data found that miR-128, Wnt1, and β-catenin expressions were upregulated in both patients and mice model with HF. Interference with miR-128 reduces Wnt1/β-catenin expression in mouse failing hearts and ameliorates heart dysfunctional properties. We identified miR-128 directly targets to Axin1, an inhibitor of Wnt/β-catenin signaling, and suppresses its inhibition on Wnt1/β-catenin. Our study provides evidence indicating miR-128 as an inducer of HF and cardiac hypertrophy by enhancing Wnt1/β-catenin in an Axin1-dependent nature. We thus suggest miR-128 has potential value in the treatment of heart failure.

Cell type-specific microRNA therapies for myocardial infarction

Current interventions fail to recover injured myocardium after infarction and prompt the need for development of cardioprotective strategies. Of increasing interest is the therapeutic use of microRNAs to control gene expression through specific targeting of mRNAs. In this Review, we discuss current microRNA-based therapeutic strategies, describing the outcomes and limitations of key microRNAs with a focus on target cell types and molecular pathways. Last, we offer a perspective on the outlook of microRNA therapies for myocardial infarction, highlighting the outstanding challenges and emerging strategies.

Insulin signaling in the heart

Insulin receptors are highly expressed in the heart and vasculature. Insulin signaling regulates cardiac growth, survival, substrate uptake, utilization, and mitochondrial metabolism. Insulin signaling modulates the cardiac responses to physiological and pathological stressors. Altered insulin signaling in the heart may contribute to the pathophysiology of ventricular remodeling and heart failure progression. Myocardial insulin signaling adapts rapidly to changes in the systemic metabolic milieu. What may initially represent an adaptation to protect the heart from carbotoxicity may contribute to amplifying the risk of heart failure in obesity and diabetes. This review article presents the multiple roles of insulin signaling in cardiac physiology and pathology and discusses the potential therapeutic consequences of modulating myocardial insulin signaling.

Insulin Resistance and Diabetes Mellitus in Alzheimer's Disease

Type 2 diabetes mellitus is a progressive disease that is characterized by the appearance of insulin resistance. The term insulin resistance is very wide and could affect different proteins involved in insulin signaling, as well as other mechanisms. In this review, we have analyzed the main molecular mechanisms that could be involved in the connection between type 2 diabetes and neurodegeneration, in general, and more specifically with the appearance of Alzheimer's disease. We have studied, in more detail, the different processes involved, such as inflammation, endoplasmic reticulum stress, autophagy, and mitochondrial dysfunction.