Investigation of the Effect of Milrinone on Renal Damage in an Experimental Non-Heart Beating Donor Model

Repurposing the familiar: Future treatment options against chronic kidney disease

OBJECTIVES

Chronic kidney disease (CKD) is a serious health issue with rising morbidity and mortality rates. Despite advances in understanding its pathophysiology, effective therapeutic options are limited, necessitating innovative treatment approaches. Also, current frontline treatments that are available against CKD are not uniformly effective and often come with significant side effects. Therefore, identifying new therapeutic targets or improving existing treatments for CKD is crucial. Drug repurposing is a promising strategy in the drug discovery process that involves screening existing approved drugs for new therapeutic applications.

KEY FINDINGS

This review discusses the pharmacological mechanisms and clinical evidence that support the efficacy of these repurposed drugs. Various drugs classes such as inodilators, endothelin-1 type A (ET-1A) receptor antagonists, bisphosphonates, mineralocorticoid receptor (MR) antagonists, DNA demethylating agents, nuclear factor erythroid 2-related factor 2 (NRF2) activators, P2X7 inhibitors, autophagy modulators, hypoxia-inducible factor-prolyl hydroxylase inhibitors (HIF-PHI) are discussed that could remarkably contribute against CKD.

SUMMARY

The review critically examines the potential for repurposing well-established drugs to slow the progression of CKD and enhance patient outcomes. This review emphasizes the importance of a multidisciplinary approach in advancing the field of drug repurposing, ultimately paving the way for innovative and effective therapies for patients suffering from CKD.

Targeting the PANoptosome Using Necrostatin-1 Reduces PANoptosis and Protects the Kidney Against Ischemia-Reperfusion Injury in a Rat Model of Controlled Experimental Nonheart-Beating Donor

PURPOSE

Reducing renal ischemia is crucial for the function and survival of grafts from nonheartbeat donors, as it leads to inflammatory responses and tubulointerstitial damage. The primary concern with organs from nonheartbeat donors is the long warm ischemia period and reperfusion injury following renal transplantation. This study had two main goals; one goal is to determine how Necrostatin-1 targeting the PANoptosome affects PANoptosis in the nonheart-beating donor rat model. The other goal is to find out if Necrostatin-1 can protect the kidney from ischemic injury for renal transplantation surgery.

METHODS

Twenty-four rats were grouped randomly as control and Necrostatin-1 in this experimental animal study, and we administered 1.65 mg/kg of Necrostatin-1 intraperitoneally to the experimental group for 30 minutes before cardiac arrest. We removed the rats' left kidneys and measured various oxidative stress marker measures such as malondialdehyde, superoxide dismutase, catalase, GPx, and 8-hydroxy-2-deoxyguanosine levels. We then subjected the tissues to immunohistochemical analysis, electron microscopy, and histopathological analysis.

FINDINGS

The Necrostatin-1 group had a lower total tubular injury score (P < .001) and less Caspase-3, gasdermin D, and mixed lineage kinase domain-like protein expression. Additionally, the apoptotic index of the study group was lower (P < .001). Furthermore, the study group had higher levels of superoxide dismutase and GPx (P < .05), whereas malondialdehyde levels were reduced (P = .009). Electron microscopy also revealed a significant improvement in tissue structure in the Necrostatin-1 group.

CONCLUSION

Necrostatin-1 protects against ischemic acute kidney injury in nonheart-beating donor rats by inhibiting PANoptosis via the blockade of RIPK1. As a result of this, Necrostatin-1 may offer novel opportunities for protecting donor kidneys from renal ischemia-reperfusion injury during transplantation in patients with end-stage kidney disease requiring a renal transplantation.

The combined effect of zinc oxide nanoparticles and milrinone on acute renal ischemia/reperfusion injury in rats: Potential underlying mechanisms

AIM

To investigate the efficacy of zinc oxide nanoparticles (ZnO-NPs) and/or milrinone (MIL) on renal ischemia/reperfusion injury (I/RI) in rats and their possible underlying mechanisms.

MATERIALS AND METHODS

Forty-eight adult male Sprague-Dawley albino rats were randomly assigned into six equal-sized groups (n = 8): normal control, sham-operated, I/R group (45 min/24 h), ZnO-NPs group (10 mg/Kg i.p.), MIL group (0.5 mg/Kg i.p.), and ZnO-NPs + MIL group in the same previous doses.

KEY FINDINGS

In comparison to the I/R-operated group, administration of either ZnO-NPs or MIL significantly decreased serum creatinine and urea concentrations, and renal vascular permeability (p < 0.05). The oxidative stress was significantly declined, as evidenced by increased GPx, CAT, and SOD activities and decreased MDA and NO concentrations. Renal expressions of TNF-α, NF-κB, KIM-1, NGAL, and caspase-3 decreased significantly, while Nrf2 increased significantly. Histopathology investigation revealed improvement with minimal renal lesions and fibrosis after ZnO-NPs or MIL treatments. The combined treatments synergistically improved the studied parameters more than either treatment alone. These findings were validated by molecular modeling, which revealed that MIL inhibited TNF-α, NF-kB, caspase-3, KIM-1 and NGAL.

SIGNIFICANCE

Both ZnO-NPs and MIL exerted cytoprotective effects against acute renal I/RI, and a combination of both was found to be even more effective. This renoprotective effect is suggested to be mediated through activation of Nrf2 and the prevention of the NF-κB activation-induced oxidative stress and inflammation, which may strengthen the potential role of ZnO-NPs or MIL in renal I/RI protection during surgical procedures.

Neuroprotective Effects of Milrinone on Acute Traumatic Brain Injury

BACKGROUND

Traumatic brain injury is still an important health problem worldwide. Traumatic brain injury not only causes direct mechanical damage to the brain but also induces biochemical changes that lead to secondary nerve cell loss. In this study, we investigated the neuroprotective effect of milrinone after traumatic brain injury (TBI) in a rat model.

METHODS

Forty male Wistar albino rats, were used. Rats were divided into 4 groups: 1) sham, 2) TBI, 3) TBI + Ringers, and 4) TBI + Milrinone. In group 1 (sham), only craniotomy was performed. In group 2 (TBI), TBI was performed after craniotomy. In group 3 (TBI + Ringer), TBI was performed after craniotomy and intraperitoneal Ringers solution was given immediately afterward. Group 4 (TBI + Milrinone), TBI was performed after craniotomy, and milrinone was given 1.0 mg/kg milrinone intraperitoneally directly (0.5 mg/kg milrinone intraperitoneally again 24 hours, 48 hours, and 72 hours after trauma). Tests were performed for neurological and neurobehavioral functions. Immunohistochemistry and histopathology studies were performed.

RESULTS

In group 4 compared with group 2 and group 3 groups, tests for neurological functions and neurobehavioral functions were significantly better. In the milrinone treatment used in group 4, plasma and brain tissue tumor necrosis factor, 8-OH 2-deoxyguanosine , and interleukin 6 levels were significantly decreased, and increased plasma and tissue IL-10 levels were detected. Histopathological spinal cord injury and apoptotic index increased in groups 2 and 3, while significantly decreasing in group 4.

CONCLUSIONS

This study shows for the first time that the anti-inflammatory, antioxidant and antiapoptotic properties of milrinone may be neuroprotective after TBI.

Targeting the PANoptosome with 3,4-Methylenedioxy-β-Nitrostyrene, Reduces PANoptosis and Protects the Kidney against Renal İschemia-Reperfusion Injury

OBJECTIVES

The objectives of this study were a) to investigate the effect of targeting the PANoptosome with 3,4-methylenedioxy-β-nitrostyrene (MNS) on PANoptosis in the Renal ischemia-reperfussion (RIR) model b) to investigate the kidney protective effect of MNS toward RIR injury.

METHODS

Thirty-two rats were divided into four groups randomly. The groups were assigned as Control, Sham, DMSO (dimethyl sulfoxide) and MNS groups. The rats in the MNS group were intraperitoneally given 20 mg/kg of MNS 30 minutes before reperfusion. 2% DMSO solvent that dissolves MNS were given to the rats in DMSO group. Left nephrectomy was performed on the rats under anesthesia at the 6th hour after reperfusion. Glutathione peroxidase (GPx), malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD) and 8-Okso-2'-deoksiguanozin (8-OHdG) levels were measured. Immunohistochemical analysis, electron microscopic and histological examinations were carried out in the tissues.

RESULTS

Total tubular injury score was lower in the MNS group (p < 0.001). Caspase-3, Gasdermin D and MLK (Mixed Lineage Kinase Domain Like Pseudokinase) expressions were considerably decreased in the MNS group (p < 0.001). Apoptotic index (AI) was found to be low in the MNS group (p < 0.001). CAT and SOD levels were higher in the MNS Group (p = 0.006, p = 0.0004, respectively). GPx, MDA, and 8-OH-dG levels were similar (p > 0.05) in all groups. MNS considerably improved the tissue structure, based on the electron microscopic analysis.

CONCLUSIONS

Our results suggested that MNS administrated before the reperfusion reduces pyroptosis, apoptosis and necroptosis. These findings suggest that MNS significantly protects the kidney against RIR injury by reducing PANoptosis as a result of specific inhibition of Nod-like receptor pyrin domain-containing 3 (NLRP 3), one of the PANoptosome proteins.

Nitrile-containing pharmaceuticals: target, mechanism of action, and their SAR studies

The nitrile group is an important functional group widely found in both pharmaceutical agents and natural products. More than 30 nitrile-containing pharmaceuticals have been approved by the FDA for the management of a broad range of clinical conditions in the last few decades. Incorporation of a nitrile group into lead compounds has gradually become a promising strategy in rational drug design as it can bring additional benefits including enhanced binding affinity to the target, improved pharmacokinetic profile of parent drugs, and reduced drug resistance. This paper reviews the existing drugs with a nitrile moiety that have been approved or in clinical trials, involving their targets, molecular mechanism of pharmacology and SAR studies, and classifies them into different categories based on their clinical usages.

Milrinone ameliorates ischaemia-reperfusion injury in experimental testicular torsion/detorsion rat model

This experimental study aims to evaluate the efficacy of milrinone against ischaemia-reperfusion injury due to testicular torsion/detorsion. Group 1 was defined as the control group. Testicular torsion/detorsion model was performed in Group 2. Group 3 had similar procedures to the rats in Group 2. In addition, 0.5 mg/kg of milrinone was administered intraperitoneally immediately after testicular torsion in Group 3. Histopathological examinations indicated a dramatic improvement in terms of inflammation, haemorrhage, oedema, congestion, Cosentino and Johnson scores in Group 3 compared to Group 2 (p = .037, p = .045, p = .018, p = .040, p = .033 and p = .03 respectively). Blood biochemical analyses, superoxide dismutase (SOD), glutathione peroxidase (GSH-px) activity and total antioxidant status (TAS) levels increased significantly in Group 3 compared to Group 2 (p = .001, p = .024 and p < .001). Malondialdehyde (MDA), protein carbonyl (PC), interleukin 1beta (IL-1beta), tumour necrosis factor-alpha (TNF-alpha) and total oxidant status (TOS) levels decreased in Group 3 compared to Group 2 (p = .001, p = .018, p < .001, p = .036 and p = .002 respectively). Tissue biochemical analyses determined an increase in SOD and GSH-px activity in Group 3 compared to Group 2, while PC and MDA levels were reduced (p = .001, p < .001, p = .038 and p < .001 respectively). Milrinone attenuates ischaemia-reperfusion injury that causes highly harmful effects due to testicular torsion/detorsion.

Development of a Rapid Mass Spectrometric Determination of AMP and Cyclic AMP for PDE3 Activity Study: Application and Computational Analysis for Evaluating the Effect of a Novel 2-oxo-1,2-dihydropyridine-3-carbonitrile Derivative as PDE-3 Inhibitor

A simple, quick, easy and cheap tandem mass spectrometry (MS/MS) method for the determination of adenosine monophosphate (AMP) and cyclic adenosine monophosphate (cAMP) has been newly developed. This novel MS/MS method was applied for the evaluation of the inhibitory effect of a novel 2-oxo-1,2-dihydropyridine-3-carbonitrile derivative, also named DF492, on PDE3 enzyme activity in comparison to its parent drug milrinone. Molecule DF492, with an IC₅₀ of 409.5 nM, showed an inhibition of PDE3 greater than milrinone (IC₅₀ = 703.1 nM). To explain the inhibitory potential of DF492, molecular docking studies toward the human PDE3A were carried out with the aim of predicting the binding mode of DF492. The presence of different bulkier decorating fragments in DF492 was pursued to shift affinity of this novel molecule toward PDE3A compared to milrinone in accordance with both the theoretical and experimental results. The described mass spectrometric approach could have a wider potential use in kinetic and biomedical studies and could be applied for the determination of other phosphodiesterase inhibitor molecules.

Combined use of dbcAMP and IBMX minimizes the damage induced by a long-term artificial meiotic arrest in mouse germinal vesicle oocytes

Phosphodiesterase (PDE)-mediated reduction of cyclic adenosine monophosphate (cAMP) activity can initiate germinal vesicle (GV) breakdown in mammalian oocytes. It is crucial to maintain oocytes at the GV stage for a long period to analyze meiotic resumption in vitro. Meiotic resumption can be reversibly inhibited in isolated oocytes by cAMP modulator forskolin, cAMP analog dibutyryl cAMP (dbcAMP), or PDE inhibitors, milrinone (Mil), Cilostazol (CLZ), and 3-isobutyl-1-methylxanthine (IBMX). However, these chemicals negatively affect oocyte development and maturation when used independently. Here, we used ICR mice to develop a model that could maintain GV-stage arrest with minimal toxic effects on subsequent oocyte and embryonic development. We identified optimal concentrations of forskolin, dbcAMP, Mil, CLZ, IBMX, and their combinations for inhibiting oocyte meiotic resumption. Adverse effects were assessed according to subsequent development potential, including meiotic resumption after washout, first polar body extrusion, early apoptosis, double-strand DNA breaks, mitochondrial distribution, adenosine triphosphate levels, and embryonic development. Incubation with a combination of 50.0 μM dbcAMP and 10.0 μM IBMX efficiently inhibited meiotic resumption in GV-stage oocytes, with low toxicity on subsequent oocyte maturation and embryonic development. This work proposes a novel method with reduced toxicity to effectively arrest and maintain mouse oocytes at the GV stage.