Co-Administration of Progesterone and Melatonin Attenuates Ischemia-Induced Hippocampal Damage in Rats

Neuroprotective-Neurorestorative Effects Induced by Progesterone on Global Cerebral Ischemia: A Narrative Review

Progesterone (P4) is a neuroactive hormone having pleiotropic effects, supporting its pharmacological potential to treat global (cardiac-arrest-related) cerebral ischemia, a condition associated with an elevated risk of dementia. This review examines the current biochemical, morphological, and functional evidence showing the neuroprotective/neurorestorative effects of P4 against global cerebral ischemia (GCI). Experimental findings show that P4 may counteract pathophysiological mechanisms and/or regulate endogenous mechanisms of plasticity induced by GCI. According to this, P4 treatment consistently improves the performance of cognitive functions, such as learning and memory, impaired by GCI. This functional recovery is related to the significant morphological preservation of brain structures vulnerable to ischemia when the hormone is administered before and/or after a moderate ischemic episode; and with long-term adaptive plastic restoration processes of altered brain morphology when treatment is given after an episode of severe ischemia. The insights presented here may be a guide for future basic research, including the study of P4 administration schemes that focus on promoting its post-ischemia neurorestorative effect. Furthermore, considering that functional recovery is a desired endpoint of pharmacological strategies in the clinic, they could support the study of P4 treatment for decreasing dementia in patients who have suffered an episode of GCI.

Neuroprotective effects of combined trimetazidine and progesterone on cerebral reperfusion injury

Cerebral ischemia-reperfusion injury induces multi-dimensional damage to neuronal cells through exacerbation of critical protective mechanisms.

Targeting more than one mechanism simultaneously namely, inflammatory responses and metabolic energy homeostasis could provide additional benefits to restrict or manage cerebral injury. Being proven neuroprotective agents both, progesterone (PG) and trimetazidine (TMZ) has the potential to add on the individual therapeutic outcomes.

We hypothesized the simultaneous administration of PG and TMZ could complement each other to synergize, or at least enhance neuroprotection in reperfusion injury. We investigated the combination of PG and TMZ on middle cerebral artery occlusion (MCAO) induced cerebral reperfusion injury in rats. Molecular docking on targets of energy homeostasis and apoptosis assessed the initial viability of PG and TMZ for neuroprotection. Animal experimentation with MCA induced ischemia-reperfusion (I/R) injury in rats was performed on five randomized groups.

Sham operated control group received vehicle (saline) while the other four I-R groups were pre-treated with vehicle (saline), PG (8 ​mg/kg), TMZ treated (25 ​mg/kg), and PG ​+ ​TMZ (8 and 25 ​mg/kg) for 7 days by intraperitoneal route. Neurological deficit, infarct volume, and oxidative stress were evaluated to assess the extent of injury in rats. Inflammatory reactivity and apoptotic activity were determined with alterations in myeloperoxidase (MPO) activity, blood-brain barrier (BBB) permeability, and DNA fragments. Reperfusion injury inflicted cerebral infarct, neurological deficit, and shattered BBB integrity.

The combination treatment of PG and TMZ restricted cellular damage indicated by significant (p ​< ​0.05) decrease in infarct volume and improvement in free radical scavenging ability (SOD activity and GSH level). MPO activity and LPO decreased which contributed in improved BBB integrity in treated rats. We speculate that inhibition of inflammatory and optimum energy utilization would critically contribute to observed neuroprotection with combined PG and TMZ treatment. Further exploration of this neuroprotective approach for post-recovery cognitive improvement is worth investigating.

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Molecular docking study.

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Drug repurposing.

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Combinatorial approach.

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Network Pharmacology.

Combination therapy for cerebral ischemia: do progesterone and noscapine provide better neuroprotection than either alone in the treatment?

Ischemic stroke presents multifaceted pathological outcomes with overlapping mechanisms of cerebral injury. High mortality and disability with stroke warrant a novel multi-targeted therapeutic approach. The neuroprotection with progesterone (PG) and noscapine (NOS) on cerebral ischemia-reperfusion (I-R) injury was demonstrated individually, but the outcome of combination treatment to alleviate cerebral damage is still unexplored. Randomly divided groups of rats (n = 6) were Sham-operated, I-R, PG (8 mg/kg), NOS (10 mg/kg), and PG + NOS (8 mg/kg + 10 mg/kg). The rats were exposed to bilateral common carotid artery occlusion, except Sham-operated, to investigate the therapeutic outcome of PG and NOS alone and in combination on I-R injury. Besides the alterations in cognitive and motor abilities, we estimated infarct area, oxidative stress, blood-brain barrier (BBB) permeability, and histology after treatment. Pharmacokinetic parameters like Cmax, Tmax, half-life, and AUC0-t were estimated in biological samples to substantiate the therapeutic outcomes of the combination treatment. We report PG and NOS prevent loss of motor ability and improve spatial memory after cerebral I-R injury. Combination treatment significantly reduced inflammation and restricted infarction; it attenuated oxidative stress and BBB damage and improved grip strength. Histopathological analysis demonstrated a significant reduction in leukocyte infiltration with the most profound effect in the combination group. Simultaneous analysis of PG and NOS in plasma revealed enhanced peak drug concentration, improved AUC, and prolonged half-life; the drug levels in the brain have increased significantly for both. We conclude that PG and NOS have beneficial effects against brain damage and the co-administration further reinforced neuroprotection in the cerebral ischemia-reperfusion injury.

Extracellular Vesicles Derived from Human Umbilical Cord Perivascular Cells Improve Functional Recovery in Brain Ischemic Rat via the Inhibition of Apoptosis

Background:

Ischemic stroke, as a health problem caused by the reduced blood supply to the brain, can lead to the neuronal death. The number of reliable therapies for stroke is limited. MSCs exhibit therapeutic achievement. A major limitation of MSC application in cell therapy is the short survival span. MSCs affect target tissues through the secretion of many paracrine agents including EVs. This study aimed to investigate the effect of HUCPVCs-derived EVs on apoptosis, functional recovery, and neuroprotection.

Methods:

Ischemia was induced by MCAO in male Wistar rats. Animals were classified into sham, MCAO, MCAO + HUCPVC, and MCAO + EV groups. Treatments began at two hours after ischemia. Expressions of apoptotic-related proteins (BAX/BCl-2 and caspase-3 and -9), the amount of TUNEL-positive cells, neuronal density (MAP2), and dead neurons (Nissl staining) were assessed on day seven post MCAO.

Results:

Administration of EVs improved the sensorimotor function (p < 0.001) and reduced the apoptotic rate of Bax/Bcl-2 ratio (p < 0.001), as well as caspases and TUNEL-positive cells (p < 0.001) in comparison to the MCAO group. EV treatment also reduced the number of dead neurons and increased the number of MAP2⁺ cells in the IBZ (p < 0.001), as compared to the MCAO group.

Conclusion:

Our findings showed that HUCPVCs-derived EVs are more effective than their mother’s cells in improving neural function, possibly via the regulation of apoptosis in the ischemic rats. The strategy of cell-free extracts is, thus, helpful in removing the predicaments surrounding cell therapy in targeting brain diseases.

Synergic Neuroprotection Between Ligusticum Chuanxiong Hort and Borneol Against Ischemic Stroke by Neurogenesis via Modulating Reactive Astrogliosis and Maintaining the Blood-Brain Barrier

Background:Ligusticum chuanxiong Hort (LCH) is a famous ethnomedicine in Asia known for its excellent output on stroke treatment, and borneol usually acts as an assistant for its reducing permeability of the blood–brain barrier (BBB) after stroke. Although their synergy against brain ischemia was verified in previous studies, the potential mechanism is still unknown.

Methods: The research aimed to explore the exact synergic mechanisms between LCH and borneol on neurogenesis within the areas of the dentate gyrus and subventricular zone. After treating middle cerebral artery occlusion rats with LCH (0.1 g/kg) and/or borneol (0.08 g/kg), the neurological severity score, brain infarct ratio, Nissl staining, Evans blue permeability, BBB ultrastructure, and expressions of von Willebrand factor and tight junction–associated proteins were measured. Co-localizations of Nestin⁺/BrdU⁺ and doublecortin⁺/BrdU⁺, and expressions of neuronal nuclei (NeuN) and glial fibrillary acidic protein (GFAP) were observed under a fluorescence microscope. Moreover, astrocyte polarization markers of complement component 3 and pentraxin 3, and relevant neurotrophins were also detected by immunoblotting.

Results: Basically, LCH and borneol had different focuses, although both of them decreased infarct areas, and increased quantity of Nissl bodies and expression of brain-derived neurotrophic factor. LCH increased the neurological severity score, NeuN⁺ cells, and the ratios of Nestin⁺/BrdU⁺ and doublecortin⁺/BrdU⁺, and decreased GFAP⁺ cells and ciliary neurotrophic factor expression. Additionally, it regulated the expressions of complement component 3 and pentraxin 3 to transform astrocyte phenotypes. Borneol improved BBB ultrastructure and increased the expressions of von Willebrand factor, tight junction–associated proteins, vascular endothelial growth factor, and vascular endothelial growth factor receptor 2. Unexpectedly, their combined therapy showed more obvious regulations on the Nissl score, Evans blue permeability, doublecortin⁺/BrdU⁺, NeuN⁺ cells, brain-derived neurotrophic factor, and vascular endothelial growth factor than both of their monotherapies.

Conclusions: The results indicated that LCH and borneol were complementary to each other in attenuating brain ischemia by and large. LCH mainly promoted neural stem cell proliferation, neurogenesis, and mature neuron preservation, which was probably related to the transformation of reactive astrocytes from A1 subtype to A2, while borneol preferred to maintain the integrity of the BBB, which provided neurogenesis with a homeostatic environment.

Possible benefits of exogenous melatonin for individuals on dialysis: a narrative review on potential mechanisms and clinical implications

Prevention of oxidative stress and inflammation in chronic kidney disease patients (CKD) on dialysis may reduce dialysis-associated complications. Administration of powerful antioxidants may improve the consequences of peritoneal dialysis (PD) and hemodialysis (HD). This narrative review aimed to show the potential therapeutic effects of melatonin (MLT) on the consequences of CKD patients receiving HD or PD. The results of preclinical and clinical studies have proven that CKD and dialysis are accompanied by reduced endogenous MLT levels and related complications such as sleep disorders. Enhanced oxidative stress, inflammation, cellular damages, and renal fibrosis, along with dysregulation of the renin-angiotensin system (RAS), have been observed in CKD and patients on dialysis. Results of studies have revealed that the restoration of MLT via the exogenous source may regulate oxidative stress, inflammation, and RAS functions, inhibit fibrosis, and improve complications in patients with long-term dialysis patients. In summary, treatment of patients with CKD and dialysis with exogenous MLT is suggested as a practical approach in reducing the outcomes and improving the quality of life in patients via antioxidant, anti-inflammatory, and anti-fibrotic signaling pathways. Therefore, this hormone can be considered in clinical practice to manage dialysis-related complications.

Dietary supplements in the management of varicocele-induced infertility: A review of potential mechanisms

Varicocele is a main cause of lower production of spermatozoon and infertility with multiple pathophysiological mechanisms. In the past decades, the use of dietary supplements has significantly increased due to both the modern lifestyle and the food shortages of the industrialised countries. The purpose of this review paper is to collect scientific evidences from basic and clinical studies which support the use of dietary supplements to define the clinical framework for patients with varicocele. In the present review, we used keywords such as dietary supplements, varicocele, male infertility, oxidative stress, DNA fragmentation, sperm parameters to find the proper articles. The standard search biomedical engines were used for seeking the papers. The use of dietary supplements such as minerals, vitamins and antioxidants has an essential role in the prevention and treatment of varicocele by increasing the levels of antioxidant enzymes (e.g. peroxidase, superoxide dismutase and catalase) and decreasing the levels of inflammatory markers (e.g. tumour necrosis factor-α, interleukin-6 and interleukin-1) in testis. According to the results, the dietary supplements may alleviate the spermatogenesis in varicocele patients through different mechanisms such as suppression of stress oxidative and inflammation in testicular tissue.

Glial Cells-The Strategic Targets in Amyotrophic Lateral Sclerosis Treatment

Amyotrophic lateral sclerosis (ALS) is a fatal neurological disease, which is characterized by the degeneration of motor neurons in the motor cortex and the spinal cord and subsequently by muscle atrophy. To date, numerous gene mutations have been linked to both sporadic and familial ALS, but the effort of many experimental groups to develop a suitable therapy has not, as of yet, proven successful. The original focus was on the degenerating motor neurons, when researchers tried to understand the pathological mechanisms that cause their slow death. However, it was soon discovered that ALS is a complicated and diverse pathology, where not only neurons, but also other cell types, play a crucial role via the so-called non-cell autonomous effect, which strongly deteriorates neuronal conditions. Subsequently, variable glia-based in vitro and in vivo models of ALS were established and used for brand-new experimental and clinical approaches. Such a shift towards glia soon bore its fruit in the form of several clinical studies, which more or less successfully tried to ward the unfavourable prognosis of ALS progression off. In this review, we aimed to summarize current knowledge regarding the involvement of each glial cell type in the progression of ALS, currently available treatments, and to provide an overview of diverse clinical trials covering pharmacological approaches, gene, and cell therapies.

Comparative effects of progesterone and the synthetic progestin norethindrone on neuroprotection in a model of spontaneous motoneuron degeneration

The Wobbler mouse has been proposed as an experimental model of the sporadic form of amyotrophic lateral sclerosis (ALS). The administration of natural progesterone (PROG) to Wobbler mice attenuates neuropathology, inhibits oxidative stress, enhances the expression of genes involved in motoneuron function, increases survival and restores axonal transport. However, current pharmacological treatments for ALS patients are still partially effective. This encouraged us to investigate if the synthetic progestin norethindrone (NOR), showing higher potency than PROG and used for birth control and hormone therapy might also afford neuroprotection. Two-month-old Wobbler mice (wr/wr) were left untreated or received either a 20 mg pellet of PROG or a 1 mg pellet of NOR for 18 days. Untreated control NFR/NFR mice (background strain for Wobbler) were also employed. Wobblers showed typical clinical and spinal cord abnormalities, while these abnormalities were normalized with PROG treatment. Surprisingly, we found that NOR did not increase immunoreactivity and gene expression for choline-acetyltransferase, drastically decreased GFAP + astrogliosis, favored proinflammatory mediators, promoted the inflammatory phenotype of IBA1+ microglia, increased the receptor for advanced glycation end products (RAGE) mRNA and protein expression and the activity of nitric oxide synthase (NOS)/NADPH diaphorase in the cervical spinal cord. Additionally, NOR treatment produced atrophy of the thymus. The combined negative effects of NOR on clinical assessments (forelimb atrophy and rotarod performance) suggest a detrimental effect on muscle trophism and motor function. These findings reinforce the evidence that the type of progestin used for contraception, endometriosis or replacement therapy, may condition the outcome of preclinical and clinical studies targeting neurodegenerative diseases.