Neuroprotective Effects of Milrinone on Experimental Acute Spinal Cord Injury: Rat Model

Beyond expectations: safinamide's unprecedented neuroprotective impact on acute spinal cord injury

BACKGROUND

Traumatic spinal cord injury (SCI) is the most common preventable cause of morbidity. Despite rapid advances in medicine, effective pharmacological treatment against SCI has not yet been confirmed. This study aimed to investigate the possible anti-inflammatory, antiapoptotic, and neuroprotective effects of safinamide after SCI in a rat model.

METHODS

A total of 40 male Wistar albino rats were randomly divided into four groups. Group 1 underwent only laminectomy. Group 2 underwent SCI after laminectomy. In group 3, SCI was performed after laminectomy, and immediately afterward, intraperitoneal physiological saline solution was administered. In group 4, SCI was performed after laminectomy, and 90 mg/kg of safinamide was given intraperitoneally immediately afterward. Moderate spinal cord damage was induced at the level of thoracic vertebra nine (T9). Neuromotor function tests were performed and levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1 beta (IL-1β) were measured. In both serum and spinal cord tissue, immunohistochemistry and histopathology studies were also conducted.

RESULTS

TNF-α, IL-1β, and IL-6 levels were found to be significantly increased in group 2 and group 3. In group 4, these levels were statistically significantly decreased. Group 4 also exhibited significant improvement in neuromotor function tests compared to the other groups. Histopathologically, it was found that group 4 showed significantly reduced inflammation and apoptosis compared to the other groups.

CONCLUSION

This study revealed that safinamide has neuroprotective effects against SCI due to its anti-inflammatory, antiapoptotic, and antioxidant activities.

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.

Promising Advances in Pharmacotherapy for Patients with Spinal Cord Injury-A Review of Studies Performed In Vivo with Modern Drugs

Spinal cord injury (SCI) is a pathological neurological condition that leads to significant motor dysfunction. It is a condition that occurs as a result of tragic accidents, violent acts, or as a consequence of chronic diseases or degenerative changes. The current treatments for patients with SCI have moderate efficacy. They improve the quality of life of patients, but they are still doomed to long-term disability. In response to the modern directions of research on possible therapeutic methods that allow for the recovery of patients with SCI, a scientific review publication is needed to summarize the recent developments in this topic. The following review is focused on the available pharmacological treatments for SCIs and the problems that patients face depending on the location of the injury. In the following review, the research team describes problems related to spasticity and neuropathic pain; possible therapeutic pathways are also described for neuroprotection and the improvement of neurotransmission within the injured spinal cord, and the review focuses on issues related to oxidative stress.

Reverse Adverse Immune Microenvironments by Biomaterials Enhance the Repair of Spinal Cord Injury

Spinal cord injury (SCI) is a severe and traumatic disorder that ultimately results in the loss of motor, sensory, and autonomic nervous function. After SCI, local immune inflammatory response persists and does not weaken or disappear. The interference of local adverse immune factors after SCI brings great challenges to the repair of SCI. Among them, microglia, macrophages, neutrophils, lymphocytes, astrocytes, and the release of various cytokines, as well as the destruction of the extracellular matrix are mainly involved in the imbalance of the immune microenvironment. Studies have shown that immune remodeling after SCI significantly affects the survival and differentiation of stem cells after transplantation and the prognosis of SCI. Recently, immunological reconstruction strategies based on biomaterials have been widely explored and achieved good results. In this review, we discuss the important factors leading to immune dysfunction after SCI, such as immune cells, cytokines, and the destruction of the extracellular matrix. Additionally, the immunomodulatory strategies based on biomaterials are summarized, and the clinical application prospects of these immune reconstructs are evaluated.

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.

Milrinone Ameliorates the Neuroinflammation and Memory Function of Alzheimer's Disease in an APP/PS1 Mouse Model

PURPOSE

Alzheimer's disease (AD) is a complex neurodegenerative disorder, which is characterized by memory loss and cognitive deficits. The neuroprotective role of milrinone on the injury of spinal cord or cerebral ischemia-reperfusion has been confirmed. However, the accurate function of milrinone on AD pathogeny is still unclear.

METHODS

APP/PS1 transgenic mouse was used to explore the role of milrinone in behaviour tests, and the effects on histopathologic features of AD such as the formation of neuronal amyloid-β (Aβ) plaque, microglial activation, tau protein hyperphosphorylation, oxidative stress, and neuroinflammation. Lipopolysaccharide (LPS)/Aβ-treated BV-2 cells were used to understand the anti-inflammation mechanism of milrinone on AD in vitro.

RESULTS

Our in vivo results showed that milrinone ameliorates the memory functions of AD mice. Meanwhile, milrinone reduced Aβ deposits, repressed microglial activation and tau protein hyperphosphorylation, attenuated the oxidative stress, and decreased the levels of inflammatory cytokines. The in vitro results demonstrated that milrinone could inhibit the secretion of interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α via regulation of NLRP3 inflammasomes and TLR4/MyD88/NF-κB signalling pathway.

CONCLUSION

Overall, milrinone could ameliorate the memory loss and cognitive deficits through repressing the multiple pathological processes of AD, suggesting that milrinone may be an underlying and effective drug for treating AD clinically.