The renin-angiotensin-aldosterone system and its suppression

TaoHeChengQi Decotion alleviate chronic renal failure via regulation of PHD2/UCP1 and RIPK3/AKT/TGF-β pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Chronic renal failure (CRF) is a late stage in the development of chronic kidney disease (CKD). Currently, there are no specific clinical drugs available. Traditional Chinese medicine (TCM), as a holistic therapeutic approach, may provide new strategies to improve the clinical management of CRF.

AIM OF THE STUDY

This study aimed to investigate the ameliorative effect of TaoHeChengQi Decoction (THCQD) on CRF and to elucidate its potential mechanism.

MATERIALS AND METHODS

Animal experiments were performed using 5/6 nephrectomy to establish a model of renal failure in rats, and serum, urine, and kidney samples were collected for study after low, medium, and high doses of (2, 4, and 8 g/kg) of THCQD were given by gavage for 8 consecutive weeks. Cellular experiments were performed using Ang II or TGF-β to stimulate HK-2 cells to produce symptoms similar to those of renal failure in vivo to evaluate the ameliorative effect and mechanism of THCQD. After clarifying the chemical composition of THCQD Tang, this study explored the pathogenesis of the disease by mass spectrometry-based proteomics technology, and used affinity ultrafiltration mass spectrometry, surface plasmon resonance, DARTS, and CETSA to investigate the pharmacological material basis of the compound, which was verified by immunoblotting and and immunofluorescence staining experiments.

RESULTS

THCQD attenuated renal injury, renal fibrosis and oxidative stress indices in serum (urine or kidney tissue) of CRF rats. Cellular experiments confirmed that THCQD also protected HK-2 cells from Ang II or TGF-β-induced injury. The mechanism of action was found to be related to the PHD2/UCP1 and RIPK3/AKT/TGF-β pathways by proteomic studies and verified by immunoblotting experiments. In addition, the pharmacodynamic material bases of PHD2/UCP1 and RIPK3/AKT/TGF-β pathways were confirmed to be amygdalin (Amy) and rhein (Rhe), respectively, by AUF-MS, SPR, CETSA and DARTS.

CONCLUSION

THCQD synergistically ameliorates 5/6 nephrectomy-induced CRF by activating PHD2/UCP2-mediated autophagy and targeting RIPK3 and its downstream TGF-β pathway. The basis of the synergistic effects of the above signaling pathways are Amy and Rhe, respectively.

Effects of oral antidiabetic agents on the renin-angiotensin-aldosterone system

BACKGROUND

The renin-angiotensin-aldosterone system (RAAS) is a vital endocrine system that plays a crucial role in maintaining homeostasis. However, excessive activation of the RAAS can contribute to the pathogenesis of certain diseases. Prolonged hyperglycemia leads to overactivation of the RAAS through the production of inflammatory factors and other mechanisms, ultimately resulting in diabetic complications. Oral antidiabetic agents are the cornerstone of diabetes treatment, and the effects of oral antidiabetic agents on the RAAS have not been clearly summarized.

OBJECTIVE

To review the effects of various types of oral antidiabetic agents on the components of the RAAS.

RESULTS

Sodium-glucose cotransporter inhibitors (SGLT2i) inhibit glucose and sodium reabsorption, which increases the flow of Na+ to the macula densa, thereby inhibiting tubuloglomerular feedback (TGF) and subsequently decreasing renin production. GLP-1 receptor agonists (GLP-1RA) and dipeptidyl peptidase-4 inhibitors (DPP-4i) can directly inhibit angiotensin II (Ang II) or indirectly suppress it by modulating TGF. These agents also affect Ang II type 1 receptors (AT1R) and Ang II type 2 receptors (AT2R) to mitigate Ang II and can indirectly interact with Ang II through Na+/H+ exchanger isotope 3 (NHE3). Thiazolidinediones (TZDs), as PPAR-γ agonists, can enhance the expression of the renin gene, inhibit the production of angiotensin-converting enzyme (ACE), regulate the levels of AT1R and AT2R, and decrease aldosterone production. Metformin also inhibits the production of renin and aldosterone in patients with polycystic ovary syndrome (PCOS).

CONCLUSIONS

These oral agents, which exhibit diverse effects on the components of the RAAS, modulate the activity of these components to exert antihypertensive, anti-inflammatory, cardioprotective, and renoprotective effects, thereby offering several beneficial outcomes in the management of diabetes.

Systemic Arterial Hypertension and Factors Associated with Blood Pressure Dysregulation in Companion Animals

Systemic arterial hypertension (SAH), characterised by a persistent increase in BP beyond the reference values for the species, is a concerning and detrimental clinical condition. The aim of this manuscript is to present the state of the art on SAH in companion animals, including the different types of hypertension, diagnostic and therapeutic approaches, and the factors associated with its occurrence, such as the role of stress. It also discusses the benefits and challenges related to the measurement process. SAH is categorised into types based on the underlying cause: situational, secondary, and idiopathic (the least frequently observed). The situational type occurs when stress is the primary factor, such as during veterinary visits, contact with other animals, or in cases of 'white coat syndrome'. If the stressor is removed, BP values tend to normalise. The most common type of SAH is the secondary form, which is associated with an underlying condition, such as renal, cardiac, endocrine, or neurological diseases, or a combination of these. Diagnosing SAH is a challenging task for many veterinarians due to factors related to handling the animal, managing the equipment, and interpreting the results. Consequently, many professionals either take inaccurate measurements or misinterpret the results, often prescribing antihypertensive medications prematurely or unnecessarily. Despite being a well-standardised and well-documented process, challenges persist. Treatment often involves antihypertensive drugs, either alone or in combination, alongside management of the underlying causes, when present. Therefore, BP values should be obtained correctly, with clinical-therapeutic decisions carefully aligned with the factors that may influence them.

Incidence, pathophysiology, risk factors, histopathology, and outcomes of COVID-19-induced acute kidney injury: A narrative review

The COVID-19 pandemic, caused by the SARS-CoV-2 virus, has led to a significant burden on global healthcare systems. COVID-19-induced acute kidney injury (AKI) is among one of the complications, that has emerged as a critical and frequent condition in COVID-19 patients. This AKI among COVID-19 patients is associated with poor outcomes, and high mortality rates, especially in those with severe AKI or requiring renal replacement therapy. COVID-19-induced AKI represents a significant complication with complex pathophysiology and multifactorial risk factors. Indeed, several pathophysiological mechanisms, including direct viral invasion of renal cells, systemic inflammation, endothelial and thrombotic abnormalities as well as nephrotoxic drugs and rhabdomyolysis are believed to underlie this condition. Moreover, histopathological and immunohistopathological findings commonly observed in postmortem studies include acute tubular necrosis, glomerular injury, and the presence of viral particles within renal tissue and urine. Identified risk factors for developing AKI vary among studies, depending on regions, underlying conditions, and the severity of the disease. Moreover, histopathological and immunohistopathological findings commonly observed in postmortem studies include show acute tubular necrosis, glomerular injury, and viral particles within renal tissue and urine. While, identified risk factors for developing AKI vary among studies, according to regions, underlying conditions, and the gravity of the disease. This narrative review aims to synthesize current knowledge on the incidence, pathophysiology, risk factors, histopathology, and outcomes of AKI induced by COVID-19.

Impact of Sleeve Gastrectomy on Kidney Function and Preemptive Transplant in Kidney Transplant Candidates With Obesity

OBJECTIVE

To compare the impact of sleeve gastrectomy (SG) on kidney function, comorbidities, and kidney transplant (KT) rates in KT candidates with obesity with a nonsurgical cohort.

METHODS

Twenty-one KT candidates with body mass index (BMI) above 35 kg/m2 underwent SG between February 26, 2021, and October 27, 2023, and were compared with 19 who did not have SG. The secondary endpoints included changes in BMI, requirements for antihyperglycemic and antihypertension medications, and preemptive KT rates.

RESULTS

The mean estimated glomerular filtration rate (eGFR) increased from a pre-SG baseline of 16.7±5.4 to 23.5±8.3 and 23.5±8.6 mL/min per 1.73 m2 at 2 and 6 months after SG (P=.002 and .02, respectively), whereas it remained unchanged in the non-SG cohort: 13.8±3.4, 14.3±5.1, and 14.8±6.4 mL/min per 1.73 m2 at the pre-evaluation period, 2 months, and 6 months. A higher baseline eGFR correlated with an improvement in eGFR after SG. The BMI and insulin requirements decreased only in the SG cohort. During the follow-up period of 5.1±4.6 months, 5 (23.8%) patients in the SG cohort and no patient in the non-SG cohort underwent preemptive KT.

CONCLUSION

Pretransplant SG improves kidney function and may consequently increase rates of preemptive KT in candidates not yet on dialysis. These findings need to be confirmed by prospective studies with a well-matched cohort.

RNA-seq reveals Lysyl oxidase as a potential biomarker of glomerular function in diabetic nephropathy in rats

PURPOSE

We downloaded the gene expression profiles of patients with diabetic nephropathyfrom the GEO database and combined it with differential gene analysis of rat transcriptome,our study employed animal models to examine the role of key hub genes in diabetic nephropathy and to pinpoint significant gene regulation in this disease.

METHODS

An examination of differential expression was performed using the online analysis tool GEO2R and the DN-related datasets GSE30528 and GSE1009 obtained from the GEO database. A comparison of gene expression between the normal and diabetic nephropathy groups was conducted using the RNA-seq technique. We further examined body weightchanges and detected the levels of blood glucose, 24-hour urine microalbumin, and expression ofIL-6 and TNF-α.We also measured the levels of Lysyl oxidase (LOX) using quantitative real-time PCR and western blotting.

RESULTS

We found that LOX was among the top 10 significantly differentially expressed genes in both the GEO database and transcriptome. Moreover, the levels of fasting blood glucose,24-h urine microalbumin, and expression of TNF-α and IL-6 were significantlyincreasedin the DNthanin the normal group (P < 0.05).

CONCLUSIONS

Our study demonstrates that the LOX gene is extensively expressed in diabetic nephropathy,with significantly upregulated expression and accompanying notable physiological markers such as TNF-α, IL-6, fasting blood glucose, and 24-hour urine microalbumin. The observed alterations indicate that the LOX gene has a potential biomarker function in the advancement of the disease.

Copeptin Hormone Concentrations in Dogs with Heart Disease and Relationship with Antidiuretic Hormone

Antidiuretic hormone (ADH) is upregulated in dogs with cardiac disease. However, measurement of ADH is impractical in a clinical setting. Copeptin is co-secreted with ADH, making it a potential biomarker of ADH secretion. We hypothesized that dogs with cardiac disease would upregulate copeptin concentrations and that copeptin would positively correlate with ADH, serum chloride ([Cl-]), and degree of mathematical [Cl-] correction. The study population comprised 19 healthy, 20 preclinical (Stage B), and 20 congestive heart failure (CHF, Stage C or D) dogs. Groups were compared with Kruskal-Wallis tests. The agreement between ADH and copeptin was assessed with Bland-Altman analysis. Relationships between copeptin and clinical variables were explored using multivariable linear regression. There were no significant differences in copeptin concentrations among healthy (median 54.9 pg/mL; range 0.5-196.1), preclinical (median 43.6 pg/mL; range 0.5-131.4), and CHF (median 60.5 pg/mL; range 0.5-997.8) dogs (p = 0.76). Relative to ADH, copeptin showed a negative proportional bias of -87.8 pg/mL with wide limits of agreement (-421.8 to 246.2). Linear regression showed a significant influence of age on copeptin concentration. Copeptin measured by ELISA does not reflect the ADH concentration in healthy dogs or in dogs with cardiac disease. Copeptin concentrations are, however, inversely associated with age.

Application of Metabolomics and the Discovery of Potential Serum Biomarkers for Diuretic Resistance in Heart Failure

Background

Diuretic resistance (DR) is characterized by insufficient fluid and sodium excretion enhancement despite maximum loop diuretic doses, indicating a phenotype of refractory heart failure (HF). Recently, metabolomics has emerged as a crucial tool for diagnosing and understanding the pathogenesis of various diseases. This study aimed to differentiate diuretic-resistant patients from non-resistant HF to identify biomarkers linked to the emergence of DR.

Methods

Serum samples from HF patients, both with and without DR, were subjected to non-targeted metabolomic analysis using liquid chromatography-tandem mass spectrometry. Metabolite variations between groups were identified using principal component analysis and orthogonal partial least-square discriminant analysis. Metabolic pathways were assessed through the Kyoto Encyclopedia of Genes and Genomes database enrichment analysis, and potential biomarkers were determined using receiver operating characteristic curves (ROCs).

Results

In total, 192 metabolites exhibited significant differences across the two sample groups. Among these, up-regulation was observed in 164 metabolites, while 28 metabolites were down-regulated. A total of 28 pathways involving neuroactive ligand-receptor interaction and amino acid biosynthesis were affected. The top five metabolites identified by ROC analysis as potential DR biomarkers were hydroxykynurenine, perillic acid, adrenic acid, 5-acetamidovalerate, and adipic acid.

Conclusions

Significant differences in metabolite profiles were observed between the diuretic-resistant and non-diuretic-resistant groups among patients with HF. The top five differentially expressed endogenous metabolites were hydroxykynurenine, perillic acid, adrenic acid, 5-acetamidovalerate, and adipic acid. The metabolic primary pathways implicated in DR were noted as amino acid, energy, and nucleotide metabolism.

Clinical Trial Registration

This study was registered with the China Clinical Trials Registry (https://www.chictr.org.cn/hvshowproject.html?id=197183&v=1.7, ChiCTR2100053587).

In the Era of Cardiovascular-Kidney-Metabolic Syndrome in Cardio-Oncology: From Pathogenesis to Prevention and Therapy

Cardiovascular-kidney-metabolic (CKM) syndrome represents a complex interplay between cardiovascular disease (CVD), chronic kidney disease (CKD), and metabolic disorders, significantly impacting cancer patients. The presence of CKM syndrome in cancer patients not only worsens their prognosis but also increases the risk of major adverse cardiovascular events (MACE), reduces quality of life (QoL), and affects overall survival (OS). Furthermore, several anticancer therapies, including anthracyclines, tyrosine kinase inhibitors, immune checkpoint inhibitors, and hormonal treatments, can exacerbate CKM syndrome by inducing cardiotoxicity, nephrotoxicity, and metabolic dysregulation. This review explores the pathophysiology of CKM syndrome in cancer patients and highlights emerging therapeutic strategies to mitigate its impact. We discuss the role of novel pharmacological interventions, including sodium-glucose cotransporter-2 inhibitors (SGLT2i), proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i), and soluble guanylate cyclase (sGC) activators, as well as dietary and lifestyle interventions. Optimizing the management of CKM syndrome in cancer patients is crucial to improving OS, enhancing QoL, and reducing MACE. By integrating cardiometabolic therapies into oncologic care, we can create a more comprehensive treatment approach that reduces the burden of cardiovascular and renal complications in this vulnerable population. Further research is needed to establish personalized strategies for CKM syndrome prevention and treatment in cancer patients.

A network toxicology and machine learning approach to investigate the mechanism of kidney injury from melamine and cyanuric acid co-exposure

BACKGROUND

Within the past two decades, high-profile cases of melamine (MA) exposure have raised significant toxicological concerns, particularly regarding food adulteration. While widely used as a fundamental organic chemical intermediate in various household products, MA's potential for unexpected toxicological synergy with its homolog, cyanuric acid (CA), remains a concern. This study aimed to investigate the nephrotoxicity of combined melamine and cyanuric acid (MC) exposure and its underlying mechanisms in rats through an integrative approach, combining network toxicology (NT), bioinformatics, and experimental validation.

MATERIALS AND METHODS

Rats were exposed to MC at doses of 0/0 mg/kg/day (Control) and 63/63 mg/kg/day (MC) for four weeks. Kidney pathology, injury markers, and RNA sequencing (RNA-seq) data were analyzed to identify differentially expressed genes between the two groups. Bioinformatics analysis, including pathway enrichment and immune microenvironment analysis, was conducted to elucidate the underlying mechanisms of MC-induced kidney injury. Potential target proteins were identified using ChEMBL, STITCH, and GeneCards databases, and hub genes were screened using three machine learning algorithms: LASSO regression, Random Forest, and Molecular Complex Detection. Molecular docking simulations were performed to assess the interactions between MC and the identified hub genes.

RESULTS

MC exposure resulted in severe kidney morphological and histological changes, as well as elevated levels of kidney injury and fibrosis markers. RNA-seq analysis revealed significant enrichment of immuno-inflammatory and apoptosis-related pathways in the MC group. Immune microenvironment analysis confirmed the infiltration of pro-inflammatory immune cells. Network toxicology analysis identified 20 potential targets associated with MC-induced kidney injury. Two hub genes, Ren and Casp3, were identified as key regulators of the renin-angiotensin-aldosterone system (RAAS) activation and apoptosis, respectively. Further experimental validation, including Western blotting and immunofluorescence, confirmed the upregulation of these proteins. Molecular docking simulations demonstrated strong binding affinities between MC and the two hub proteins.

CONCLUSION

MC exposure induces significant kidney injury and fibrosis. The activation of the RAAS pathway and apoptosis plays a crucial role in MC-mediated nephrotoxicity. However, additional vivo experimental validation is lacking. Future studies should focus on further exploration for the mechanism of MC-induced nephrotoxicity and more rigorous experimental validation.

A comprehensive review on cardiovascular disorders development due to salt intake: an emphasis on policy implementation

Excessive salt consumption has been linked with the emergence of hypertension, which further leads to cardiovascular disease development among other medical conditions. This has resulted in leading world institutions such as the WHO coming up with relevant plans to minimize its use. Lower-middle-income countries (LMICs) have greatest burden of noncommunicable diseases (NCDs), with hypertension being a common condition. Reduction of salt intake is a great control measure in minimizing the rise in prevalence of hypertension or cardiovascular diseases. Many countries have agreed and even formulated their salt reduction policies as recommended by the WHO, however, the challenge is widely noted in implementation. Thus, few countries have been able to achieve the global WHO recommended standards of daily salt intake. Salt is the main source of sodium in our diets, which is an essential component responsible for the balance of the extracellular fluid volume but may lead to salt-induced hypertension when used excessively. The achievement of salt reduction is predicated on multiple factors such as knowledge, attitude and practice of the public. Therefore, localizing interventions with strategies such as public media campaigns, reformulation of processed foods (mandatory and voluntary) and front-of-packaging labelling awareness. Some of the reasons for failure in implementation include economic challenges, lack of visionary leadership, stakeholder struggles and poor planning and execution of strategies. This review aims to elaborate on the development of cardiovascular diseases or hypertension due to salt usage and the recent advancement regarding salt reduction policies. Further, we assess the need for proper implementation with the United Kingdom as a case study. In conclusion, most governments have made the right decisions in developing or recommending salt reduction strategies to the food industry. However, more focus is needed to ensure effective implementation of the plans.

Renin-Angiotensin-Aldosterone System Profiling in Horses Before and After Exercise

BACKGROUND

The impact of exercise on the classical and alternative renin-angiotensin-aldosterone system (RAAS) pathways has not been studied in horses.

HYPOTHESIS

We hypothesized that exercise would activate both RAAS pathways and that endurance exercise would cause more activation of the classical pathway compared to short-duration, high-intensity exercise in horses.

ANIMALS

Twenty-five horses (21 client-owned and 4 research) were included in 4 exercise groups (10 Arabians, 50-mile ride [A-E]; 4 thoroughbreds, 1-mile treadmill exercise [TB-TM]; 5 thoroughbreds, 1-1/16th-mile race [TB-R]; and 6 quarter horses 330-500-yard race [QH-R]).

METHODS

Blood was collected before and after exercise. Equilibrium analysis was performed to measure serum RAAS metabolites and enzyme activities. The components of the RAAS pathways were compared before and after exercise. Post/pre-exercise ratios for each variable were compared among exercise groups. Data were reported as median (first, third quartiles; pre vs. post) and p < 0.05 was considered significant.

RESULTS

Exercise increased classical RAAS metabolites (pmol/L; angiotensin I, 2.5 [2.5, 2.5] vs. 8.2 [2.5, 19.0]; angiotensin II, 10.2 [6.0, 21.9] vs. 53.0 [37.4, 95.8]; aldosterone, 83.8 [53.4, 149.5] vs. 170.6 [112.2, 251.7]); alternative RAAS metabolites (pmol/L; angiotensin 1-7, 1.5 [1.5, 1.5] vs. 5.1 [1.5, 12.5]; angiotensin 1-5, 2.5 [2.5, 7.3] vs. 14.9 [9.0, 25.4]) and angiotensin-converting enzyme-2 activity (ng/mL; 16.6 [13.9, 20.4] vs. 25.2 [20.2, 33.0]; p < 0.001) for all horses. Angiotensin 1-7 ratios were higher for TB-R compared with TB-TM and A-E (p < 0.001).

CONCLUSIONS AND CLINICAL IMPORTANCE

Both classical and alternative RAAS pathways increase after exercise in horses.

Angiotensin type 1 and type 2 receptors-induced mitochondrial dysfunction promotes ferroptosis in cardiomyocytes

Previous studies suggest that ferroptosis is involved in cardiovascular diseases. The aim of the present study is to investigate the causal relationship between angiotensin II type 1 and type 2 receptors (AT1/2R) activities and mitochondrial dysfunction in induction of cardiomyocyte ferroptosis. Human AC16 cardiomyocytes were first pre-treated with an AT1/2R blockers, before stimulated with angiotensin II (Ang II) for 24 h. The redox status of the cardiomyocytes were assessed by measuring the cellular malondialdehyde (MDA), superoxide dismutase (SOD), and Nicotinamide-adenine dinucleotide phosphate, (NADPH) levels using biochemical methods. Mitochondrial reactive oxygen specifics (mitROS), mitochondrial memebrane potential, and Fe2+ levels were determined using flow cytometry. The signaling pathways, including the glutathione peroxidase 4 (GPX4), heme oxygenase-1 (HO-1), sirtuin1, and ferroptosis suppressor protein 1 (FSP1)-coenzyme Q10 (CoQ10) pathways, were evaluated using western blotting. Our results demonstrated that Ang II significantly elevated the levels of MDA, Fe2+, mitoROS, and FtMt and markedly reduced SOD, NADPH, mitochondrial membrane potential, GPX4, HO-1, Sirt1, SFXN1, Nrf2, and FSP1 levels in cardiomyocyte, which were reversed by blockade of AT1/2R. Our results suggest that AT1/2R signaling can induce myocardial ferroptosis by impairing mitochondrial function via multiple signaling pathways, including the cyst (e)ine /GSH/GPX4 axis and FSP1/coenzyme Q10 (CoQ10) axis.

Does COVID-19 Cause Non-Dıpper Hypertension?

Coronavirus disease 2019 (COVID-19) remains a health problem worldwide. The present study aimed to investigate the effect of blood pressure (BP) on the circadian pattern and prevalence of new-onset non-dipper hypertension in the post-COVID period in patients with known hypertension. This prospective single-center study included 722 patients hospitalized for COVID-19 infection. Ambulatory BP (ABP) data were collected during their initial hospitalization. The ABP data were reassessed 1 month after the patients were discharged. The results were compared with a healthy control group with known hypertension but without COVID-19 infection. After exclusion criteria were applied, the study included 187 patients with COVID-19 and 136 healthy hypertensive controls. Post-COVID ABP showed that patients with COVID-19 had significantly higher mean 24-h systolic and diastolic BP, mean nighttime systolic and diastolic BP, and mean daytime diastolic BP than the control group. In addition, new-onset non-dipper hypertension was significantly higher in patients with COVID-19. This study demonstrated for the first time that the circadian pattern is disturbed and a non-dipper pattern develops in individuals with known hypertension during the post-COVID period.

Association between pan-immune-inflammation value and heart failure: Evidence from the NHANES 2011-2020

ObjectiveThis study aimed to explore the association between pan-immune-inflammation value and heart failure outcomes using data from the nationally representative National Health and Nutrition Examination Survey database.MethodsWe conduct a cross-sectional cohort analysis using National Health and Nutrition Examination Survey data, including participants aged ≥20 years with available pan-immune-inflammation value data. We performed smooth curve fitting and threshold analysis, using both linear and non-linear regression models, to assess dose-response relationship and explore the continuous effect of pan-immune-inflammation value on heart failure outcomes.ResultsOur analysis revealed a significant and independent non-linear association between elevated pan-immune-inflammation value levels and an increased risk of heart failure occurrence. After adjustment for multiple covariates, these findings remained consistent and each increment unit in logarithmic pan-immune-inflammation value is associated with 34% increase in the risk of heart failure occurrence. Furthermore, we identified an inflection point of logarithmic pan-immune-inflammation value = 5.98 as a critical threshold. Stratified analyses revealed that the association between pan-immune-inflammation value and heart failure occurrence remains consistent across different subgroups.ConclusionsThis study confirmed the clinical value of pan-immune-inflammation value as a novel inflammatory biomarker in the assessment and monitoring of heart failure.

The Role of Reductive Stress in the Pathogenesis of Endocrine-Related Metabolic Diseases and Cancer

Reductive stress (RS), characterized by excessive accumulation of reducing equivalents such as NADH and NADPH, is emerging as a key factor in metabolic disorders and cancer. While oxidative stress (OS) has been widely studied, RS and its complex interplay with endocrine regulation remain less understood. This review explores molecular circuits of bidirectional crosstalk between metabolic hormones and RS, focusing on their role in diabetes, obesity, cardiovascular diseases, and cancer. RS disrupts insulin secretion and signaling, exacerbates metabolic inflammation, and contributes to adipose tissue dysfunction, ultimately promoting insulin resistance. In cardiovascular diseases, RS alters vascular smooth muscle cell function and myocardial metabolism, influencing ischemia-reperfusion injury outcomes. In cancer, RS plays a dual role: it enhances tumor survival by buffering OS and promoting metabolic reprogramming, yet excessive RS can trigger proteotoxicity and mitochondrial dysfunction, leading to apoptosis. Recent studies have identified RS-targeting strategies, including redox-modulating therapies, nanomedicine, and drug repurposing, offering potential for novel treatments. However, challenges remain, particularly in distinguishing physiological RS from pathological conditions and in overcoming therapy-induced resistance. Future research should focus on developing selective RS biomarkers, optimizing therapeutic interventions, and exploring the role of RS in immune and endocrine regulation.

Association between serum creatinine-to-albumin ratio and 28-day mortality in intensive care unit patients following cardiac surgery: analysis of mimic-iv data

BACKGROUND

Creatinine-to-albumin ratio (CAR) has been recognized as a predictive indicator in the postoperative setting. However, its relationship with outcomes in patients receiving cardiac surgery remains elusive. This study aimed to discuss the link between CAR and 28-day mortality in patients admitted to intensive care unit (ICU) following cardiac surgery, hoping to provide some insights for targeted interventions for improvement of patient outcomes.

METHODS

MIMIC-IV database was searched to obtain data of patients admitted to ICU following cardiac surgery. Retrieved patients were split into three groups based on CAR levels. The 28-day ICU mortality in each group was evaluated and compared using Kaplan-Meier analysis. Subgroup analysis, multivariate Cox regression and restricted cubic spline (RCS) analysis were used to further examine the relationship between CAR and outcomes. Receiver operating characteristic (ROC) curves were used to assess the predictive ability of CAR. Mediation analysis was conducted to investigate the potential mechanism by which CAR affects 28-day ICU mortality.

RESULTS

A total of 5,670 patients were included and divided into three groups. Patients with high CAR values (CAR ≥ 0.31) had a significantly increased rate of 28-day ICU mortality (11.4%), as compared to those with low CAR levels (CAR < 0.23, 1.83%). In addition, patients with high CAR values (CAR ≥ 0.31) had a lowest survival rate than the other two groups (p < 0.0001). ROC curve analysis showed that CAR exhibited a moderate predictive power (AUC = 0.748). Moreover, CAR was identified as a strong risk factor for 28-day ICU mortality, and a significant dose-response association was presented. Further subgroup analysis revealed pronounced mortality risks in females and patients without chronic conditions such as chronic kidney disease (CKD) and type 2 diabetes mellitus (T2DM). Mediation analysis indicated that CAR affected 28-day ICU mortality through biomarkers like chloride (39.8%), glucose (11.8%), potassium (24.4%), and sodium (28.3%).

CONCLUSION

CAR served as a risk factor for 28-day ICU mortality in patients receiving cardiac surgery, and it showed a complex dose-response and subgroup-specific association with 28-day ICU mortality. Additionally, CAR affected 28-day ICU mortality through multiple key biomarkers, providing some insights for targeted interventions.

Mitochondrial Dysfunction in Diabetes: Shedding Light on a Widespread Oversight

Diabetes mellitus represents a complicated metabolic condition marked by ongoing hyperglycemia arising from impaired insulin secretion, inadequate insulin action, or a combination of both. Mitochondrial dysfunction has emerged as a significant contributor to the aetiology of diabetes, affecting various metabolic processes critical for glucose homeostasis. This review aims to elucidate the complex link between mitochondrial dysfunction and diabetes, covering the spectrum of diabetes types, the role of mitochondria in insulin resistance, highlighting pathophysiological mechanisms, mitochondrial DNA damage, and altered mitochondrial biogenesis and dynamics. Additionally, it discusses the clinical implications and complications of mitochondrial dysfunction in diabetes and its complications, diagnostic approaches for assessing mitochondrial function in diabetics, therapeutic strategies, future directions, and research opportunities.

The renin-angiotensin-aldosterone system in kidney diseases of cats and dogs

The renin-angiotensin-aldosterone system (RAAS) has a well-established key pathophysiologic role in kidney diseases, and pharmacotherapy targeting this system is a mainstay of treatment of affected human beings, cats, and dogs. Several studies have evaluated the circulating RAAS in animals with spontaneous or experimentally induced kidney diseases. Evidence supporting the activation of this system has been demonstrated in some - but not all - studies and individuals, and the interindividual variability in circulating RAAS markers is high. Advances over the last few decades have expanded our understanding of the system, which now includes the existence of a counterbalancing "alternative" RAAS and tissular renin-angiotensin systems (RASs), the latter regulated independently of the circulating endocrine RAAS. The local RAS in the kidney, termed the intrarenal RAS, is currently recognized as an important regulator of kidney function and mediator of kidney disease. In general, information on the intrarenal RAS is lacking in cats and dogs with kidney diseases; however, existing limited data suggest its activation. Despite the inconsistent evidence for circulating RAAS activation in chronic kidney diseases, RAAS inhibitors have proven effective for the treatment of its common comorbidities, systemic arterial hypertension and renal proteinuria, in both cats and dogs. Further research of the circulating RAAS, the intrarenal RAS, and the interplay between these systems in the context of kidney diseases in companion animals might contribute to the development or refinement of future treatment strategies.

Antidiuretic hormone concentrations in dogs with heart disease and relationship to serum chloride

INTRODUCTION/OBJECTIVES

Non-osmotic antidiuretic hormone (ADH) release promotes electrolyte-free water retention in dogs with congestive heart failure (CHF), contributing to low electrolyte concentrations. We hypothesized that dogs with CHF would have higher ADH concentrations than healthy dogs and dogs with preclinical heart disease, and that ADH concentrations would positively correlate to the amount of chloride [Cl-] correction but not serum osmolality.

ANIMALS, MATERIALS AND METHODS

The study population comprised 20 healthy, 20 preclinical, and 20 CHF dogs. Serum electrolytes, serum osmolality, and plasma ADH were measured and compared between groups using the Kruskal-Wallis test. Relationships between ADH and electrolytes, the amount of [Cl-] correction, osmolality, and the use of amlodipine and renin-angiotensin-aldosterone system inhibitors were explored with multiple linear regression.

RESULTS

Preclinical (median 6.5 pg/mL; range 1.8 pg/mL-33.8 pg/mL) and CHF (6.7 pg/mL; range 2.0 pg/mL-28.1 pg/mL) dogs had higher ADH concentrations than healthy dogs (median 3.4 pg/mL; range 0.1 pg/mL-6.2 pg/mL) (P=0.004) but there was no difference between preclinical and CHF dogs. Serum ADH was inversely correlated with [Cl-] (P=0.026, rs = -0.287) and c[Cl-] (P=0.008, rs = -0.338). Amlodipine use and [Cl-] predicted ADH after controlling for age, weight, use of renin-angiotensin aldosterone inhibitors, and osmolality. There was no significant relationship between ADH and the amount of [Cl-] correction, osmolality, or serum sodium.

DISCUSSION

The inverse relationship between ADH and serum [Cl-] and the positive relationship with amlodipine use suggests neurohormonal stimulation as a common mechanism. Uncoupling of ADH from osmolality and serum sodium is consistent with non-osmotic release, which was present even in dogs with preclinical heart disease.

CONCLUSIONS

Antidiuretic hormone was elevated in dogs with heart disease but was not a unique feature of advanced heart disease.

Diagnosis and Management of Hypertensive Heart Disease: Incorporating 2023 European Society of Hypertension and 2024 European Society of Cardiology Guideline Updates

Hypertensive heart disease (HHD) continues to be a leading cause of cardiovascular morbidity and mortality worldwide, necessitating the evolution of evidence-based management strategies. This literature review examines the most recent updates from the 2023 and 2024 hypertension guidelines issued by the European Society of Hypertension (ESH) and the European Society of Cardiology (ESC). These guidelines are compared with previous key recommendations, such as the 2017 American College of Cardiology/American Heart Association guidelines and the 2018 ESC/ESH guidelines. The updated recommendations reflect a paradigm shift in the approach to hypertension diagnosis and management, including a stricter systolic blood pressure (BP) target of 120-129 mmHg, which underscores the importance of early and precise BP control. The difference between the classification of "elevated BP" and hypertension in the ESC versus ESH guidelines, particularly, regarding their implications for early detection and prevention of HHD, are critically examined, highlighting areas of clinical and academic debate. The introduction of a new "elevated BP" category (120-139/70-89 mmHg) highlights a proactive strategy aimed at identifying at-risk individuals earlier in the disease course to prevent progression to HHD. Additionally, the divergent roles of hypertension-mediated organ damage (HMOD), including HHD, in risk stratification as recommended by the ESC and ESH are discussed, emphasising their significance in tailoring management approaches. For patients with resistant hypertension, the 2023 and 2024 updates also endorse innovative therapies, such as renal denervation, an interventional procedure that has demonstrated significant promise in managing treatment-resistant cases. This review synthesises these updates, focusing on their implications for clinical practice in diagnosing and managing HHD. By emphasising aggressive intervention and the integration of novel treatment modalities, the review aims to bridge existing gaps in earlier approaches to hypertension management. The critical evaluation of guideline discrepancies and evolving evidence seeks to provide clinicians with a nuanced understanding to optimise outcomes for patients with HHD, particularly considering emerging therapeutic possibilities and more stringent BP control targets.

A perspective on small molecules targeting the renin-angiotensin-aldosterone system and their utility in cardiovascular diseases: exploring the structural insights for rational drug discovery and development

Renin-angiotensin-aldosterone system (RAAS) is crucial in cardiovascular homeostasis. Any disruption in this homeostasis often leads to numerous cardiovascular diseases (CVDs) and non-cardiovascular diseases. Small molecules that show ability toward mechanically modulating RAAS components have been developed to address this problem, thus providing opportunities for innovative drug discovery and development. This review is put forth to provide a comprehensive understanding not only on the signaling mechanisms of RAAS that lead to cardiovascular events but also on the use of small molecules targeting the modulation of RAAS components. Further, the detailed descriptions of the drugs affecting the RAAS and their pharmacodynamics, kinetics, and metabolism profiles are provided. This article also covers the limitations of the present therapeutic armory, followed by their mechanistic insights. A brief discussion is offered on the analysis of the chemical space parameters of the drugs affecting RAAS compared to other cardiovascular and renal categories of medications approved by the US FDA. This review provides structural insights and emphasizes the importance of integrating the current therapeutic regimen with pharmacological tactics to accelerate the development of new therapeutics targeting the RAAS components for improved and efficacious cardiovascular outcomes. Finally, chemical spacing parameters of RAAS modulators are provided, which will help in understanding their peculiarities in modulating the RAAS signaling through structural and functional analyses. Furthermore, this review will assist medicinal chemists working in this field in developing better drug regimens with improved selectivity and efficacy.

Traditional Chinese Medicine Formulae and Chinese Patent Medicines for the Treatment of Diabetic Kidney Disease: Efficacies and Mechanisms

Diabetic kidney disease is one of the most significant comorbidities of diabetic patients, and has become the second cause of end-stage renal disease. Current clinical management programs have difficulty in reducing morbidity and poor prognosis, and thus new treatment options and concepts need to be developed. Traditional Chinese medicine formulae and Chinese patent medicines contain a variety of medicinal flavors, laying the material foundation for the multi-target, multi-level therapeutic features. This study describes the main pathologic features of DKD as well as its pathogenesis. Additionally, the categorization of TCM according to its different therapeutic mechanisms is discussed, and the signaling pathways targeted and corresponding biological effects are described in detail. For example, TCM formulae can alleviate oxidative stress through pathways such as Nrf2 and NOX4, can inhibit the development of inflammation through pathways such as TGF-β and NF-κB, and can ameliorate DKD by inhibiting endoplasmic reticulum stress and apoptosis. Moreover, it highlights the superior efficacy of the combined application of TCM formulae and Western medicine over Western medicine alone, which can compensate for the shortcomings of existing DKD treatment methods to a certain extent. TCM formulae and CPMs are promising candidates for the auxiliary treatment of DK, however, the lack of clarity regarding the active ingredients intensifies the difficulty of integrating TCM formulae and CPMs into clinical practice. Further research is warranted to explore the material basis and molecular mechanisms of action of TCM formulae against DKD.

Retrospective evaluation of risk factors for worsening renal function after angiotensin-converting enzyme inhibitor treatment in dogs

BACKGROUND

Angiotensin-converting enzyme inhibitors (ACEi) have the potential to cause worsening renal function (WRF). Therefore, reevaluation of renal function is recommended 1-2 weeks after starting ACEi therapy.

OBJECTIVES

To identify risk factors for WRF in dogs receiving ACEi for cardiac diseases, proteinuria, or systemic hypertension.

ANIMALS

A total of 156 client-owned dogs that received ACEi were included.

METHODS

Serum creatinine concentration was determined at the initial presentation and first reevaluation to detect and grade WRF (increase in sCr ≥ 0.3 mg/dL). Grade 1 (nonazotemic), 2 (mild), and 3 (moderate to severe) WRF were characterized by sCr remaining ≤1.6 mg/dL, 1.7-2.5 mg/dL increase, and 2.6-5.0 mg/dL increase, respectively. Demographic and serum chemistry data, such as total protein, albumin, blood urea nitrogen, creatinine, symmetric dimethylarginine, glucose, triglyceride, total cholesterol concentrations, and serum electrolyte concentrations at first presentation, were evaluated. Multivariable modeling was performed to identify risk factors for WRF after treatment with ACEi.

RESULTS

Worsening renal function was identified in 27/156 (17%, 95% confidence interval [CI], 0.11-0.23) dogs after ACEi treatment. It was classified as Grades 1, 2, and 3 in 17, 2, and 8 dogs, respectively. The only significant factors associated with WRF in dogs receiving ACEi were concurrent administration of furosemide (odds ratio, 5.05; 95% CI, 2.05-12.4; P < .001) and pre-existing azotemia (odds ratio, 3.21; 95% CI, 1.28-8.03; P = .01).

CONCLUSIONS AND CLINICAL IMPORTANCE

Although WRF is uncommon and mild, ACEi should be cautiously prescribed in dogs receiving furosemide or those with pre-existing azotemia.

Trajectory of Cardiogenic Dementia: A New Perspective

The functions of the heart and brain are closely linked and essential to support human life by the heart-brain axis, which is a complex interconnection between the heart and brain. Also, cardiac function and cerebral blood flow regulate the brain's metabolism and function. Therefore, deterioration of cardiac function may affect cognitive function and may increase the risk of dementia. Cardiogenic dementia is defined as a cognitive deterioration due to heart diseases such as heart failure, myocardial infarction, and atrial fibrillation. The prevalence of cognitive impairment in patients with heart failure was 29%. In addition, coronary artery disease (CAD) is also associated with the development of cognitive impairment. CAD and reduction of myocardial contractility reduced cerebral blood flow and increased the risk of dementia in CAD patients. Furthermore, myocardial infarction and subsequent systemic haemodynamic instability promote the development and progression of cardiogenic dementia. These findings indicated that many cardiac diseases are implicated in the development and progression of cognitive impairment. Nevertheless, the underlying mechanism for the development of cardiogenic dementia was not fully elucidated. Consequently, this review aims to discuss the potential mechanisms involved in the pathogenesis of cardiogenic dementia.

Frequency and progression of azotemia during acute and chronic treatment of congestive heart failure in cats

BACKGROUND

Azotemia is common in cats with congestive heart failure (CHF) and might be exacerbated by diuretic therapy.

HYPOTHESIS/OBJECTIVES

Determine frequency, risk factors, and survival impact of progressive azotemia in cats treated for CHF.

ANIMALS

One hundred and sixteen client-owned cats with kidney function testing performed at least twice during acute or chronic CHF treatment.

METHODS

Serum creatinine (sCr) and electrolyte concentrations were determined at multiple clinical timepoints to detect azotemia and kidney injury (KI; sCr increase ≥0.3 mg/dL). Furosemide dosage between timepoints was calculated. Multivariable modeling was performed to identify predictors of KI, change in serum biochemistry results, and survival.

RESULTS

Azotemia was common at all timepoints, including initial CHF diagnosis (44%). Kidney injury was documented in 66% of cats. Use of a furosemide continuous rate infusion was associated with increased risk of KI during hospitalization (odds ratio, 141.6; 95% confidence interval [CI], 12.1-6233; P = .01). Higher furosemide dosage was associated with increase in sCr during hospitalization (P = .03) and at first reevaluation (P = .01). Treatment with an angiotensin converting enzyme inhibitor was associated with fewer lifetime KI events (P = .02). Age in years was the only variable associated with shorter survival (hazard ratio, 1.1; 95% CI, 1.0-1.1; P = .03). Neither sCr nor KI were associated with long-term outcome.

CONCLUSIONS AND CLINICAL IMPORTANCE

Azotemia and KI were common in cats during CHF treatment but did not impact survival.

Amiodarone Advances the Apoptosis of Cardiomyocytes by Repressing Sigmar1 Expression and Blocking KCNH2-related Potassium Channels

BACKGROUND

Heart failure (HF) is the ultimate transformation result of various cardiovascular diseases. Mitochondria-mediated cardiomyocyte apoptosis has been uncovered to be associated with this disorder.

OBJECTIVE

This study mainly delves into the mechanism of the anti-arrhythmic drug amiodarone on mitochondrial toxicity of cardiomyocytes.

METHODS

The viability of H9c2 cells treated with amiodarone at 0.5, 1, 2, 3, and 4 μM was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and Sigmar1 expression was examined by quantitative real-time PCR (qRTPCR). After transfection, the viability, apoptosis, reactive oxygen species (ROS) level, mitochondrial membrane potential (MMP), and potassium voltage-gated channel subfamily H member 2 (KCNH2) expression in H9c2 cells were assessed by MTT, flow cytometry, ROS assay kit, mitochondria staining kit, and Western blot.

RESULTS

Amiodarone at 1-4 μM notably weakened H9c2 cell viability with IC50 value of 2.62 ± 0.43 μM. Amiodarone at 0.5-4 μM also evidently suppressed the Sigmar1 level in H9c2 cells. Amiodarone repressed H9c2 cell viability and KCNH2 level and triggered apoptosis, ROS production and mitochondrial depolarization, while Sigmar1 upregulation reversed its effects. Moreover, KCNH2 silencing neutralized the effect of Sigmar1 up-regulation on H9c2 cell viability, apoptosis, and ROS production.

CONCLUSION

Amiodarone facilitates the apoptosis of H9c2 cells by restraining Sigmar1 expression and blocking KCNH2-related potassium channels.

Dose-exposure-response of CARDALIS® (benazepril/spironolactone) on the classical and alternative arms of the renin-angiotensin-aldosterone system in healthy dogs

BACKGROUND

Benazepril exhibits a dose-dependent effect on biomarkers of the circulating renin-angiotensin-aldosterone system (RAAS) in dogs.

HYPOTHESIS/OBJECTIVES

To characterize the dose-exposure-response relationship of a fixed-dose combination product including benazepril and spironolactone (CARDALIS®) on RAAS biomarkers in dogs.

ANIMALS

Eighteen purpose-bred healthy beagle dogs.

METHODS

Three groups of 6 dogs received different doses of CARDALIS® for 14 days following induction of RAAS activation by feeding a low-sodium diet: (a) benazepril 0.25 mg/kg + spironolactone 2 mg/kg PO q24h (label dose); (b) benazepril 0.25 mg/kg + spironolactone 2 mg/kg PO q12h; or (c) benazepril 0.5 mg/kg + spironolactone 4 mg/kg PO q12h. Blood samples were collected at baseline and serial time intervals after CARDALIS® dosing to measure serum RAAS biomarkers and plasma concentrations of active drug metabolites. Time-weighted averages for serum RAAS biomarkers after CARDALIS® dosing at steady state were compared between dosage groups using Wilcoxon rank-sum testing.

RESULTS

Compared to the label dose, the highest dose of CARDALIS® was associated with a 30% decrease in angiotensin II (P = .03), 94% increase in angiotensin 1-7 (P = .03), 71% decrease in surrogate activity of ACE (P = .002), and 116% increase in circulating aldosterone (P = .02). CARDALIS® was well-tolerated at all doses with no clinically relevant changes in renal values or serum electrolytes.

CONCLUSIONS AND CLINICAL IMPORTANCE

The combined CARDALIS® product leads to dose-dependent alterations of RAAS metabolites. These results could help inform clinical trials in dogs with heart disease.

CLOCK gene 3'UTR and exon 9 polymorphisms show a strong association with essential hypertension in a North Indian population

BACKGROUND

Hypertension (HTN) is a medical condition characterized by persistent systolic and diastolic blood pressures of ≥ 140 mmHg and ≥ 90 mmHg, respectively. With more than 1200 million adult patients aged 30-79 years worldwide according to the latest WHO data, HTN is a major health risk factor; more importantly, 46% of patients are unaware of this condition. Essential hypertension (EH), also known as primary hypertension, is the predominant subtype and has a complex etiology that involves both genetic and non-genetic factors. Majority of living organisms are influenced by the light and dark cycle of a day and respond to these changes through an intricate clock referred to as the "biological clock" or "circadian rhythm". The connection between circadian rhythm and blood pressure is well established, with many studies supporting the role of circadian rhythm gene mutation(s)/polymorphism(s) in EH. To date, no such data are available from any Indian population.

METHODS

This case‒control study was conducted on 405 EH patients and 505 healthy controls belonging to the Jammu region of North India after an informed consent was obtained from the participants. A total of three single nucleotide variants, two in the CLOCK gene (rs1801260 and rs34789226) and one in the BMAL1/ARNTL gene (rs6486121), were selected for genotyping. Genotyping was performed via the RFLP technique, and the applicable statistical analyses were performed via the SPSS and SNPStats programs.

RESULTS

Logistic regression analysis revealed a statistically significant association of both CLOCK gene variants rs1801260 (T > C 3'UTR) and rs34789226 (C > T Exon 9) and a nonsignificant association of the BMAL1/ARNTL intronic variant rs6486121 (C > T) with EH. The 3'UTR variant showed a statistically significant association under the codominant (p < 0.0001), dominant (p < 0.0001), and recessive (p = 0.0004) models. In contrast, the exon 9 variant showed a statistically significant negative association under the codominant (p = 0.003) and dominant (p = 0.015) models only. The rs6486121/rs1801260 and rs1801260/rs34789226/rs6486121 haplotypes showed significant differences in their distribution between cases and controls (p < 0.0001). Certain genotypes and haplotypes were found more common in hypertensive males than females.

CONCLUSION

This is a first report linking circadian rhythm gene polymorphisms with EH in any Indian population. The statistically significant association of the CLOCK gene 3'UTR and exon 9 polymorphisms with EH, highlight the potential role of this gene and probably other genes of the circadian pathway in the etiology of EH in the study population. Additionally, our study also revealed that certain genotypes are making males more susceptible to EH.

A multi-omics approach identifies the key role of disorders of sphingolipid metabolism in Ang II-induced hypertensive cardiomyopathy myocardial remodeling

Hypertension-induced myocardial remodelling encompasses both structural and functional changes in cardiac muscle tissue, such as myocardial hypertrophy, fibrosis, and inflammation. These alterations not only impair the systolic and diastolic functions of the heart but also elevate the risk of cardiovascular events and heart failure. One of the primary contributors to hypertensive cardiomyopathy (HTN-CM) is the over-activation of the renin-angiotensin-aldosterone system (RAAS), which subsequently induces myocardial remodeling. Although conventional therapeutic strategies aim to suppress RAAS and slow the progression of heart failure, the primary challenge in treating HTN-CM remains the lack of sensitive and specific biomarkers for early detection of myocardial remodelling. Combined multi-omics analyses, complemented by experimental validation, offer a systematic understanding of the landscape of gene/protein/metabolite expression in HTN-CM, revealing the underlying mechanisms of angiotensin II (Ang II)-induced myocardial remodeling in HTN-CM. Transcriptomic analysis revealed that differentially expressed genes (DEGs) are implicated in sphingolipid metabolic processes and are associated with collagen synthesis and inflammatory responses, collectively contributing to myocardial remodeling in HTN-CM. Proteomic analysis demonstrated that differentially expressed proteins (DEPs) are also involved in inflammatory and fibrotic processes, with associations to sphingolipid signaling pathways, particularly manifested through elevated expression of IL6, COL4A1, FGG, FGB, CREBBP and SPHK2 proteins. Metabolomic profiling further elucidated the increased expression of bioactive sphingolipid metabolites S1P and Sa1P in the myocardium of HTN-CM. Integrative multi-omics analysis revealed that HTN-CM is primarily influenced by the sphingolipid signaling pathway, with additional associations to the HIF-1α and FoxO signaling pathways. Correlation analysis has highlighted strong associations between sphingolipids and genes/proteins related to fibrosis and inflammation, as well as their connection to the HIF-1α and FoxO signalling pathways. Furthermore, certain key indicators were validated through ELISA and Western blot analyses in both plasma and myocardial tissue. In conclusion, the findings of this study suggest that excessive Ang II may induce abnormalities in sphingolipid metabolism, resulting in increased levels of S1P in both circulating and myocardial tissues. This elevation in S1P is implicated in myocardial inflammatory and fibrotic alterations, highlighting its pivotal role in myocardial remodeling. The specific mechanism underlying the sphingolipid signaling pathway in myocardial remodeling may involve downstream biological processes, including oxidative stress and excessive mitochondrial autophagy, mediated by HIF-1α and FoxO.

SIRT1-FOXOs signaling pathway: A potential target for attenuating cardiomyopathy

Cardiomyopathy constitutes a global health burden. It refers to myocardial injury that causes alterations in cardiac structure and function, ultimately leading to heart failure. Currently, there is no definitive treatment for cardiomyopathy. This is because existing treatments primarily focus on drug interventions to attenuate symptoms rather than addressing the underlying causes of the disease. Notably, the cardiomyocyte loss is one of the key risk factors for cardiomyopathy. This loss can occur through various mechanisms such as metabolic disturbances, cardiac stress (e.g., oxidative stress), apoptosis as well as cell death resulting from disorders in autophagic flux, etc. Sirtuins (SIRTs) are categorized as class III histone deacetylases, with their enzyme activity primarily reliant on the substrate nicotinamide adenine dinucleotide (NAD (+)). Among them, Sirtuin 1 (SIRT1) is the most intensively studied in the cardiovascular system. Forkhead O transcription factors (FOXOs) are the downstream effectors of SIRT1. Several reports have shown that SIRT1 can form a signaling pathway with FOXOs in myocardial tissue, and this pathway plays a key regulatory role in cell loss. Thus, this review describes the basic mechanism of SIRT1-FOXOs in inhibiting cardiomyocyte loss and its favorable role in cardiomyopathy. Additionally, we summarized the SIRT1-FOXOs related regulation factor and prospects the SIRT1-FOXOs potential clinical application, which provide reference for the development of cardiomyopathy treatment.

Angiotensin II type-1 receptor autoantibody positively correlates with the rate of metaphase I oocytes in infertility with ovulatory disorder

The renin-angiotensin system (RAS) plays an important role in reproductive function. Our previous study identified that angiotensin II type-1 receptor autoantibody (AT1-AA), an autoantibody that activates RAS, was closely associated with infertility. However, its distribution in different types of infertility remained unclear. This study was designed to explore the distribution of AT1-AA in infertile patients and the connections between AT1-AA and oocyte development and pregnancy outcome. A total of 184 infertile women participated, with samples collected from peripheral venous blood. ELISA was used to detect AT1-AA levels in their sera. It was observed that the proportion of ovulation-disorder factors in AT1-AA-positive group was significantly higher than that in negative group (P=0.001). In 59 infertile women with ovulatory disorders, compared with negative group, AT1-AA-positive group had lower rate of retrieval (P=0.032) and metaphase II (MII) oocytes (P=0.011) but higher proportion of metaphase I (MI) oocytes (P=0.019). A negative correlation was found between the levels of AT1-AA and rate of retrieval and MII oocytes (P=0.027; P=0.043), whereas a positive correlation was observed with the proportion of MI oocytes (P=0.002). Moreover, a specific predictive value for proportion of reaching MII and MI oocytes was exhibited by AT1-AA (P < 0.01; P < 0.05). But no significant difference in embryonic parameters or pregnancy outcomes between two groups was observed (P > 0.05). This study revealed that serum AT1-AA levels were significantly increased in infertile women with ovulatory disorders and positively correlated with proportion of MI oocytes, but not associated with outcomes of assisted reproduction.

Global prevalence and contributing factors of transplant renal artery stenosis in renal transplant recipients: A systematic review and meta-analysis

Transplant renal artery stenosis (TRAS) is a serious complication of renal transplantation, with its prevalence and associated factors remaining inconclusive. The aim of this study was to assess the global prevalence and risk factors associated with TRAS incidence in renal transplant recipients. We conducted a meta-analysis by collecting data on the prevalence and factors associated with TRAS from articles in Scopus, Embase, and PubMed. The prevalence of TRAS was determined using a single-arm meta-analysis. The factors associated with TRAS were determined using Mantel-Haenszel analysis or inverse variance analysis. Out of 28,599 articles from the searches, 31 of them were included in the analysis. The global prevalence of TRAS was 6% among renal transplant recipients. Diabetes mellitus, hypertension, longer duration of dialysis before transplant, deceased donor, acute rejection, delayed graft function, longer cold ischemic time, and prolonged peak systolic velocity were associated with an increased risk of TRAS. Age, sex, peripheral artery disease (PAD) comorbidity, causes of end-stage renal disease (ESRD), previous dialysis modality, and cytomegalovirus infection were not associated with TRAS incidence. In conclusion, the global prevalence of TRAS in renal transplant recipients is relatively high, and some of the contributing factors to the development of TRAS are preventable. These findings could serve as a guideline for informing the management of TRAS in the future.

A comprehensive review of biomarker research in diabetic nephropathy from a global bibliometric and visualization perspective

BACKGROUND

Diabetic nephropathy (DN) is a common complication of diabetes, which is prone to develop into end-stage renal disease, and early diagnosis and treatment is the key to effective management of DN. Biomarkers have important clinical significance in the diagnosis and treatment of DN and have attracted extensive attention from researchers in recent years. The aim of this study was to visualize the field of biomarker research in DN through bibliometric analysis, to summarize the current status and predict future trends of this field, with a view to providing valuable insights for scholars and policy makers.

METHODS

Literature search and data collection from Web of Science Core Collection. Calculations and visualizations were performed using Microsoft Excel, VOSviewer, Bibliometrix R-package, and CiteSpace.

RESULTS

We identified 1274 publications about biomarker research in DN from 1995 to November 01, 2023, with a steady increase in annual publications. China, Steno Diabetes Center in Denmark, and Frontiers in Endocrinology were the most productive country, institution, and journal, respectively; Mischak, Harald was both the most productive and highly cited author, and Kidney International was the most cited journal. The high frequency keywords were "albuminuria," "chronic kidney disease" and "expression." In addition, "macrophage," "fibrosis" and "omics" are potentially promising topics.

CONCLUSION

Our study comprehensively and visually summarized the important findings of global biomarker research in DN and revealed the structure, hotspots, and evolutionary trends in this field. It would inspire subsequent studies from a macroscopic perspective and provide a basis for rational allocation of resources and identification of collaborations among researchers.

The role of the gut microbiota in the onset and progression of heart failure: insights into epigenetic mechanisms and aging

BACKGROUND

The gut microbiota (GM) plays a critical role in regulating human physiology, with dysbiosis linked to various diseases, including heart failure (HF). HF is a complex syndrome with a significant global health impact, as its incidence doubles with each decade of life, and its prevalence peaks in individuals over 80 years. A bidirectional interaction exists between GM and HF, where alterations in gut health can worsen the disease's progression.

MAIN BODY

The "gut hypothesis of HF" suggests that HF-induced changes, such as reduced intestinal perfusion and altered gut motility, negatively impact GM composition, leading to increased intestinal permeability, the release of GM-derived metabolites into the bloodstream, and systemic inflammation. This process creates a vicious cycle that further deteriorates heart function. GM-derived metabolites, including trimethylamine N-oxide (TMAO), short-chain fatty acids (SCFAs), and secondary bile acids (BAs), can influence gene expression through epigenetic mechanisms, such as DNA methylation and histone modifications. These epigenetic changes may play a crucial role in mediating the effects of dysbiotic gut microbial metabolites, linking them to altered cardiac health and contributing to the progression of HF. This process is particularly relevant in older individuals, as the aging process itself has been associated with both dysbiosis and cumulative epigenetic alterations, intensifying the interplay between GM, epigenetic changes, and HF, and further increasing the risk of HF in the elderly.

CONCLUSION

Despite the growing body of evidence, the complex interplay between GM, epigenetic modifications, and HF remains poorly understood. The dynamic nature of epigenetics and GM, shaped by various factors such as age, diet, and lifestyle, presents significant challenges in elucidating the precise mechanisms underlying this complex relationship. Future research should prioritize innovative approaches to overcome these limitations. By identifying specific metabolite-induced epigenetic modifications and modulating the composition and function of GM, novel and personalized therapeutic strategies for the prevention and/or treatment of HF can be developed. Moreover, targeted research focusing specifically on older individuals is crucial for understanding the intricate connections between GM, epigenetics, and HF during aging.

Epigenetics of Hypertensive Nephropathy

Hypertensive nephropathy (HN) is a leading cause of chronic kidney disease (CKD) and end-stage renal disease (ESRD), contributing to significant morbidity, mortality, and rising healthcare costs. In this review article, we explore the role of epigenetic mechanisms in HN progression and their potential therapeutic implications. We begin by examining key epigenetic modifications-DNA methylation, histone modifications, and non-coding RNAs-observed in kidney disease. Next, we discuss the underlying pathophysiology of HN and highlight current in vitro and in vivo models used to study the condition. Finally, we compare various types of HN-induced renal injury and their associated epigenetic mechanisms with those observed in other kidney injury models, drawing inferences on potential epigenetic therapies for HN. The information gathered in this work indicate that epigenetic mechanisms can drive the progression of HN by regulating key molecular signaling pathways involved in renal damage and fibrosis. The limitations of Renin-Angiotensin-Aldosterone System (RAAS) inhibitors underscore the need for alternative treatments targeting epigenetic pathways. This review emphasizes the importance of further research into the epigenetic regulation of HN to develop more effective therapies and preventive strategies. Identifying novel epigenetic markers could provide new therapeutic opportunities for managing CKD and reducing the burden of ESRD.

Bisphenol S exposure induces cardiac remodeling and aggravates high-fat diet-induced cardiac hypertrophy in mice

Bisphenol S (BPS) is widely used in the manufacture products and increase the risk of cardiovascular diseases. The effect of the association between obesity and BPS on cardiac outcomes is still unknown. Male C57BL/6 mice were divided into standard chow diet (SC; 15 kJ/g), standard chow diet + BPS (SCB), high-fat diet (HF; 21 kJ/g), and high-fat diet + BPS (HFB). Over 12 weeks, the groups were exposed to BPS through drinking water (dose: 25 μg/kg/day) and/or a HF diet. We evaluated: body mass (BM), total cholesterol, systolic blood pressure (SBP), left ventricle (LV) mass, and cardiac remodeling. In the SCB group, BM, total cholesterol, and SBP increase were augmented in relation to the SC group. In the HF and HFB groups, these parameters were higher than in the SC and SCB groups. Cardiac hypertrophy was evidenced by augmented LV mass and wall thickness, and ANP protein expression in all groups in comparison to the SC group. Only the HFB group had a thicker LV wall than SCB and HF groups, and increased cardiomyocyte area when compared with SC and SCB groups. Concerning cardiac fibrosis, SCB, HF, and HFB groups presented higher interstitial collagen area, TGFβ, and α-SMA protein expression than the SC group. Perivascular collagen area was increased only in the HF and HFB groups than SC group. Higher IL-6, TNFα, and CD11c protein expression in all groups than the SC group evidenced inflammation. All groups had elevated CD36 and PPARα protein expression in relation to the SC group, but only HF and HFB groups promoted cardiac steatosis with increased perilipin 5 protein expression than the SC group. BPS exposure alone promoted cardiac remodeling with pathological concentric hypertrophy, fibrosis, and inflammation. Diet-induced remodeling is aggravated when associated with BPS, with marked hypertrophy, alongside fibrosis, inflammation, and lipid accumulation.

Effect of furosemide on comprehensive renin-angiotensin-aldosterone system activity of Thoroughbred horses

BACKGROUND

Furosemide, a commonly used diuretic, activates the renin-angiotensin-aldosterone system (RAAS) in other species. Little is known about RAAS peptide activation in horses.

HYPOTHESIS/OBJECTIVES

To evaluate equilibrium analysis as a practical method for RAAS quantification in horses and describe the RAAS response to a single dose of furosemide. We hypothesize that furosemide would cause transient increase in RAAS peptides in horses.

ANIMALS

14 healthy adult thoroughbreds from a university teaching herd.

METHODS

Horses received either furosemide (1 mg/kg IV) or saline IV in a crossover study design. Protease-inhibited samples were compared with equilibrium analysis samples with Deming regression analysis. Renin-angiotensin-aldosterone system hormones were evaluated at 0, 0.25, 0.5, 4, and 24 hours postadministration, via equilibrium analysis. Values were compared with a mixed effects model.

RESULTS

Correlation between protease inhibition and equilibrium analysis was high for angiotensin I peptide (AngI) and angiotensin II peptide (AngII) (r = .92 and .95, respectively). Baseline RAAS peptide concentrations were below the limit of detection except AngII (median, 7.5 [range, 3.5-14.0] pmol/L). Furosemide administration resulted in an increase in AngI (8.0 [0.5-15.5] pmol/L, P = .03), AngII (33.7 [9.6-57.9] pmol/L, P = .0008), angiotensin III peptide (AngIII) (2.9 [0.9-4.9] pmol/L, P = .0005), angiotensin IV peptide (AngIV) (2.0 [0.6-3.4] pmol/L, P = .0005), and angiotensin 1-5 peptide (Ang1-5) (5.6 [1.2-5.9] pmol/L, P = .003) at 4 hours. Differences are reported as difference in the mean (95% confidence interval [CI]).

CONCLUSIONS AND CLINICAL IMPORTANCE

Furosemide produced an increase in hormones associated with both the classical and alternative RAAS pathways. Serum equilibrium analysis is practical for RAAS analysis in horses.

Plasma N-terminal pro-B-type natriuretic peptide and urinary aldosterone-to-creatinine ratio in healthy Chihuahuas

BACKGROUND

Chihuahua represents an increasingly widespread breed predisposed to cardiac disease. N-terminal pro-B-type natriuretic peptide (NT-proBNP) might be a useful point-of-care biomarker for dogs suspected of having heart disease, but breed differences have been reported. The urinary aldosterone-to-creatinine ratio (UAldo: C) appears to be a good indicator of renin-angiotensin-aldosterone system activity in dogs, but Chihuahuas showed significantly higher UAldo: C than other breeds. The objective of this study was to assess preliminary breed-specific reference intervals for NT-proBNP and UAldo: C in healthy Chihuahuas and evaluate sex differences in these parameters.

RESULTS

Forty-three healthy Chihuahuas dogs were enrolled. The median NT-proBNP was 347 (125-515) pmol/L, and the median UAldo: C was 2.59 (1.57-4.61) µg/g. The NT-proBNP reference interval was 125 (90% CI 125-125) - 2121.4 (90% CI 941.6-2248) pmol/L. 91% of the Chihuahuas were below the nonbreed-specific cut-off (900 pmol/L). The UAldo: C reference interval was 0.6 (90% CI 0.5-0.9) - 16.8 (90% CI 10.9-27.4) µg/g. No significant sex differences in NT-proBNP or UAldo: C were found.

CONCLUSIONS

The median value, interindividual coefficient of variation and reference interval of NT-proBNP were in line with those reported for other small breeds. In contrast to previous studies, no sex differences in NT-proBNP were detected. As previously suggested, Chihuahuas seem to be characterized by higher values of UAldo: C than other breeds.

Coexisting nutcracker phenomenon and refractory hypertension in a patient with IgA nephropathy: A case report and literature review

The entrapment of the left renal vein (LRV) may contribute to changes in hemodynamics within kidney and could also be associated with IgA nephropathy (IgAN). Although the relationship between the nutcracker phenomenon and IgAN has not yet been elucidated, it is speculated that this patient's refractory hypertension is a combined effect of nutcracker syndrome (NCS) and IgAN.

Modelling hemodynamics regulation in rats and dogs to facilitate drugs safety risk assessment

Pharmaceutical companies routinely screen compounds for hemodynamics related safety risk. In vitro secondary pharmacology is initially used to prioritize compounds while in vivo studies are later used to quantify and translate risk to humans. This strategy has shown limitations but could be improved via the incorporation of molecular findings in the animal-based toxicological risk assessment. The aim of this study is to develop a mathematical model for rat and dog species that can integrate secondary pharmacology modulation and therefore facilitate the overall pre-clinical safety translation assessment. Following an extensive literature review, we built two separate models recapitulating known regulation processes in dogs and rats. We describe the resulting models and show that they can reproduce a variety of interventions in both species. We also show that the models can incorporate the mechanisms of action of a pre-defined list of 50 pharmacological mechanisms whose modulation predict results consistent with known pharmacology. In conclusion, a mechanistic model of hemodynamics regulations in rat and dog species has been developed to support mechanism-based safety translation in drug discovery and development.

Dysregulation of the 3β-hydroxysteroid dehydrogenase type 2 enzyme and steroid hormone biosynthesis in chronic kidney disease

Introduction

Chronic kidney disease (CKD) presents a critical global health challenge, marked by the progressive decline of renal function. This study explores the role of the 3β-hydroxysteroid dehydrogenase type 2 enzyme (HSD3B2) and the steroid hormone biosynthesis pathway in CKD pathogenesis and progression.

Methods

Using an adenine-induced CKD mouse model, we conducted an untargeted metabolomic analysis of plasma samples to identify key metabolite alterations associated with CKD. Immunohistochemistry, Western blotting, and qPCR analyses were performed to confirm HSD3B2 expression in both human and mouse tissues. Additionally, Nephroseq and Human Protein Atlas data were utilized to assess the correlation between HSD3B2 and kidney function. Functional studies were conducted on HK2 cells with HSD3B2 knockdown to evaluate the impact on cell proliferation and apoptosis.

Results

Metabolic characteristics revealed significant shifts in CKD, with 61 metabolites increased and 65 metabolites decreased, highlighting the disruption in steroid hormone biosynthesis pathways influenced by HSD3B2. A detailed examination of seven key metabolites underscored the enzyme's central role. HSD3B2 exhibited a strong correlation with kidney function, supported by data from Nephroseq and the Human Protein Atlas. Immunohistochemistry, Western blotting, and qPCR analyses confirmed a drastic reduction in HSD3B2 expression in CKD-affected kidneys. Suppressed proliferation and increased apoptosis rates in HSD3B2 knocked down HK2 cells further demonstrated the enzyme's significance in regulating renal pathophysiology.

Discussion

These findings underscore the potential of HSD3B2 as a clinical diagnostic and therapeutic target in CKD. While further studies are warranted to fully elucidate the mechanisms, our results provide valuable insights into the intricate interplay between steroid hormone biosynthesis and CKD. This offers a promising avenue for precision medicine approaches and personalized treatment strategies.

Possible mechanisms of SARS-CoV-2-associated myocardial fibrosis: reflections in the post-pandemic era

Since December 2019, coronavirus disease 2019 (COVID-19) has been spreading worldwide with devastating immediate or long-term effects on people's health. Although the lungs are the primary organ affected by COVID-19, individuals infected with SARS-CoV-2 also develop systemic lesions involving multiple organs throughout the body, such as the cardiovascular system. Emerging evidence reveals that COVID-19 could generate myocardial fibrosis, termed "COVID-19-associated myocardial fibrosis." It can result from the activation of fibroblasts via the renin-angiotensin-aldosterone system (RAAS), transforming growth factor-β1 (TGF-β1), microRNAs, and other pathways, and can also occur in other cellular interactions with SARS-CoV-2, such as immunocytes, endothelial cells. Nonetheless, to gain a more profound insight into the natural progression of COVID-19-related myocardial fibrosis, additional investigations are necessary. This review delves into the underlying mechanisms contributing to COVID-19-associated myocardial fibrosis while also examining the antifibrotic potential of current COVID-19 treatments, thereby offering guidance for future clinical trials of these medications. Ultimately, we propose future research directions for COVID-19-associated myocardial fibrosis in the post-COVID-19 era, such as artificial intelligence (AI) telemedicine. We also recommend that relevant tests be added to the follow-up of COVID-19 patients to detect myocardial fibrosis promptly.

Handgrip Strength Is Inversely Associated With the Progression of Kidney Damage in a General Japanese Population: A Prospective Cohort Study

Background Handgrip strength is an indicator of muscle function and a predictor of health outcomes. However, only a few studies have examined the association between handgrip strength and the development of kidney damage. This study aimed to investigate the longitudinal association of handgrip strength with kidney damage in a general Japanese population. Methods This prospective cohort study enrolled participants with normal kidney function who attended annual health check-ups in Ibaraki Prefecture, Japan, between April 2016 and March 2020. Clinical information, including data from blood and urine tests, physiological examinations, and handgrip strength tests, was collected at enrollment. Lifestyle information was also collected via a self-administered questionnaire. The study participants were followed up for the progression of kidney damage until March 2023. Relative handgrip strength was calculated by dividing the handgrip strength by the body mass index to adjust for differences in body mass. A Cox proportional hazards model was used to examine the relationship between relative handgrip strength and the progression of kidney damage. Results A total of 4304 participants with normal kidney function were enrolled in this study. During the mean follow-up period of approximately 4 years (SD 1.8 years), 15.4% of the participants developed kidney damage. After adjusting for covariates, higher relative handgrip strength was associated with a lower risk of kidney damage in men (HR = 0.63, 95% CI: 0.43 - 0.90; p = 0.012), but no significant association was observed in women. Conclusions Higher relative handgrip strength is associated with a lower risk of kidney damage in men. This finding highlights the importance of muscle strength in preventing kidney damage.

Adherence to Dietary Approaches to Stop Hypertension (DASH) Diet as a Protective Factor for Ischemic Stroke and Its Influence on Disability Level: A Case-Control Study in Lebanon

BACKGROUND

Hypertension is a major risk factor for ischemic stroke. An important strategy in controlling hypertension is dietary modification. The present study evaluates the effect of Dietary Approaches to Stop Hypertension (DASH) diet on the risk of ischemic stroke.

METHODS

A case-control study was carried out, including 214 ischemic stroke cases recruited within the first 48 h of diagnosis and 214 controls, divided equally into hospitalized and non-hospitalized participants. Controls were matched to cases based on age and gender. Socio-demographic characteristics were assessed, in addition to adherence to the DASH diet, which was measured using a preconstructed DASH diet index (ranging from 0 (lowest) to 11 (highest)). For stroke patients, Modified Rankin Score (mRS) was measured to assess disability.

RESULTS

Smoking, hypertension, hyperlipidemia, atrial fibrillation, and myocardial infarction were significantly associated with ischemic stroke (p < 0.001). Higher adherence to the DASH diet was correlated to lower rates of stroke, where cases scored 5.042 ± 1.486 compared to 6.654 ± 1.471 for controls (p < 0.001). Eating more grains, vegetables, fruits, dairy products, nuts, seeds, and beans, and lower levels of fat, fewer sweets, and less sodium were associated with lower rates of ischemic stroke (p = 0.038 for sweets and p < 0.001 for all the remaining), while meat, poultry, and fish did not have any significant effect (p = 0.46). A multivariate analysis showed that lower adherence to the DASH diet (p < 0.001, OR: 0.526, CI95% 0.428-0.645) was associated with a higher incidence of ischemic stroke and an increased likelihood of having high disability levels (mRS 5-6) (p = 0.041, OR: 2.49 × 10-8, CI95% 0-2.49 × 10-8).

CONCLUSIONS

The relation between the DASH diet and risk of stroke highlights the necessity for strict adherence to dietary restrictions, suggesting a protective role for the DASH diet in stroke pathogenesis and prognosis.

Post-myocardial infarction heart failure and long-term high-fat diet: Cardiac endoplasmic reticulum stress and unfolded protein response in Sprague Dawley rat model

BACKGROUND

Myocardial infarction (MI) significantly contributes to the global mortality rate, often leading to heart failure (HF) due to left ventricular remodeling. Key factors in the pathomechanism of HF include nitrosative/oxidative stress, inflammation, and endoplasmic reticulum (ER) stress. Furthermore, while a high-fat diet (HFD) is known to exacerbate post-MI cardiac remodeling, its impact on these critical factors in the context of HF is not as well understood.

AIMS

This study aimed to assess the impact of post-MI HF and HFD on inflammation, nitro-oxidative stress, ER stress, and unfolded protein response (UPR).

METHODS

The study was performed on fragments of the left ventricle harvested from 30 male adult Sprague Dawley rats, which were divided into four groups based on diet (normal-fat vs. high-fat) and surgical procedure (sham operation vs. coronary artery ligation to induce MI). We assessed body weight, NT-proBNP levels, protein levels related to nitrosative/oxidative stress, ER stress, UPR, apoptosis, and nitric oxide synthases, through Western Blot and ELISA.

RESULTS

HFD and MI significantly influenced body weight and NT-proBNP concentrations. HFD elevated 3-nitrotyrosine and myeloperoxidase levels and altered nitric oxide synthase levels. HFD and MI significantly affected ER stress markers and activated or inhibited UPR pathways.

CONCLUSIONS

The study demonstrates significant impacts of post-MI HF and dietary fat content on cardiac function and stress markers in a rat model. The interaction between HFD and MI on UPR activation suggests the importance of dietary management in post-MI recovery and HF prevention.

Mechanistic insights into carvedilol's potential protection against doxorubicin-induced cardiotoxicity

Doxorubicin (DOX) is an anthracycline chemotherapy drug widely employed in the treatment of various cancers, known for its potent antineoplastic properties but often associated with dose-dependent cardiotoxicity, limiting its clinical use. This review explores the complex molecular details that determine the heart-protective effectiveness of carvedilol in relation to cardiotoxicity caused by DOX. The harmful effects of DOX on heart cells could include oxidative stress, DNA damage, iron imbalance, disruption of autophagy, calcium imbalance, apoptosis, dysregulation of topoisomerase 2-beta, arrhythmogenicity, and inflammatory responses. This review carefully reveals how carvedilol serves as a strong protective mechanism, strategically reducing each aspect of cardiac damage caused by DOX. Carvedilol's antioxidant capabilities involve neutralizing free radicals and adjusting crucial antioxidant enzymes. It skillfully manages iron balance, controls autophagy, and restores the calcium balance essential for cellular stability. Moreover, the anti-apoptotic effects of carvedilol are outlined through the adjustment of Bcl-2 family proteins and activation of the Akt signaling pathway. The medication also controls topoisomerase 2-beta and reduces the renin-angiotensin-aldosterone system, together offering a thorough defense against cardiotoxicity induced by DOX. These findings not only provide detailed understanding into the molecular mechanisms that coordinate heart protection by carvedilol but also offer considerable potential for the creation of targeted treatment strategies intended to relieve cardiotoxicity caused by chemotherapy.

Molecular Features of Calcific Aortic Stenosis in Female and Male Patients

Over the past 15 years, sex-related differences in aortic valve (AV) stenosis (AS) have been highlighted, affecting various aspects of AS, such as the pathophysiology, AV lesions, left ventricle remodelling, and outcomes. Female patients were found to present a more profibrotic pattern of leaflet remodelling and/or thickening, whereas male patients have a preponderance of calcification within stenosed leaflets. The understanding of these sex differences is still limited, owing to the underrepresentation of female patients in many basic and clinical research studies and trials. A better understanding of sex differences in the pathophysiology of AS may highlight new therapeutic targets that potentially could be sex-specific. This review aims to summarize sex-related differences in AS, as discovered from basic research experiments, covering aspects of the disease ranging from leaflet composition to signalling pathways, sex hormones, genetics and/or transcriptomics, and potential sex-adapted medical treatments.

Untangling the Uncertain Role of Overactivation of the Renin-Angiotensin-Aldosterone System with the Aging Process Based on Sodium Wasting Human Models

Every individual at some point encounters the progressive biological process of aging, which is considered one of the major risk factors for common diseases. The main drivers of aging are oxidative stress, senescence, and reactive oxygen species (ROS). The renin-angiotensin-aldosterone system (RAAS) includes several systematic processes for the regulation of blood pressure, which is caused by an imbalance of electrolytes. During activation of the RAAS, binding of angiotensin II (ANG II) to angiotensin II type 1 receptor (AGTR1) activates intracellular nicotinamide adenine dinucleotide phosphate (NADPH) oxidase to generate superoxide anions and promote uncoupling of endothelial nitric oxide (NO) synthase, which in turn decreases NO availability and increases ROS production. Promoting oxidative stress and DNA damage mediated by ANG II is tightly regulated. Individuals with sodium deficiency-associated diseases such as Gitelman syndrome (GS) and Bartter syndrome (BS) show downregulation of inflammation-related processes and have reduced oxidative stress and ROS. Additionally, the histone deacetylase sirtuin-1 (SIRT1) has a significant impact on the aging process, with reduced activity with age. However, GS/BS patients generally sustain higher levels of sirtuin-1 (SIRT1) activity than age-matched healthy individuals. SIRT1 expression in GS/BS patients tends to be higher than in healthy age-matched individuals; therefore, it can be assumed that there will be a trend towards healthy aging in these patients. In this review, we highlight the importance of the hallmarks of aging, inflammation, and the RAAS system in GS/BS patients and how this might impact healthy aging. We further propose future research directions for studying the etiology of GS/BS at the molecular level using patient-derived renal stem cells and induced pluripotent stem cells.

Clinical Properties and Non-Clinical Testing of Mineralocorticoid Receptor Antagonists in In Vitro Cell Models

Mineralocorticoid receptor antagonists (MRAs) are one of the renin-angiotensin-aldosterone system inhibitors widely used in clinical practice. While spironolactone and eplerenone have a long-standing profile in clinical medicine, finerenone is a novel agent within the MRA class. It has a higher specificity for mineralocorticoid receptors, eliciting less pronounced adverse effects. Although approved for clinical use in patients with chronic kidney disease and heart failure, intensive non-clinical research aims to further elucidate its mechanism of action, including dose-related selectivity. Within the field, animal models remain the gold standard for non-clinical testing of drug pharmacological and toxicological properties. Their role, however, has been challenged by recent advances in in vitro models, mainly through sophisticated analytical tools and developments in data analysis. Currently, in vitro models are gaining momentum as possible platforms for advanced pharmacological and pathophysiological studies. This article focuses on past, current, and possibly future in vitro cell models research with clinically relevant MRAs.