S-oxiracetam Facilitates Cognitive Restoration after Ischemic Stroke by Activating α7nAChR and the PI3K-Mediated Pathway

Oxiracetam ameliorates neurological function after traumatic brain injury through competing endogenous RNA regulatory network

RATIONALE

Oxiracetam (ORC) has been demonstrated to improve neurological function resulting from traumatic brain injury (TBI).

OBJECTIVES

This study aims to explore the precise molecular mechanism of ORC in the treatment of TBI.

METHODS

TBI rat model was established and treated with ORC. Modified Garcia score, rotarod test and HE staining were employed to evaluate the neuroprotective effects of ORC. Subsequently, RNA-seq was conducted on the hippocampus of sham, TBI and ORC rats to identify differential expression (DE) lncRNAs and mRNAs. Functional analysis of DE lncRNAs and mRNAs was performed. The real-time quantitative polymerase chain reaction (qRT-PCR) was used to determine the expression of DE lncRNAs and DE mRNAs. Western blot was performed to explore important pathway in ceRNA networks.

RESULTS

ORC has been demonstrated to effectively improve neurological function in TBI rats. A total of 10 ORC-treated DE lncRNAs and 61 DE mRNAs were obtained. A co-expression network comprising 79 lncRNA-mRNA pairs associated with the treatment of ORC was constructed. Furthermore, an lncRNA-miRNA-mRNA regulated ceRNA network was constructed, comprising 15 mRNAs, 41 miRNAs and 10 lncRNAs. Functional enrichment, qRT-PCR, and Western blot analysis showed that ORC improve neurological function of TBI rats by regulating multiple signaling pathways, including the JAK-STAT/PI3K-Akt pathway, as well as affecting the expression of key genes Prlr, Cdkn1a, and Cldn1.

CONCLUSION

Our study reveals the mechanism of ORC therapy in TBI rats, which mainly relies on the regulation of the JAK-STAT/PI3K-Akt pathway and the influence on the expression of key genes Prlr, Cdkn1a, and Cldn1.

Effect of l-oxiracetam and oxiracetam on memory and cognitive impairment in mild-to-moderate traumatic brain injury patients: Study protocol for a randomized controlled trial

Objectives

Patients with traumatic brain injury (TBI) often suffer memory and cognitive impairments, and oxiracetam-like drugs are considered to have a positive impact on these symptoms potentially. However, the efficacy and safety of l-oxiracetam and oxiracetam in TBI patients have not been sufficiently investigated.

Methods

The study adopts a multicenter, randomized, double-blind, parallel-group, phase 3 clinical trial design in 74 centers across 51 hospitals in China. A total of 590 TBI patients meeting criteria will be randomly allocated into three groups in a 2:2:1 ratio: l-oxiracetam group, oxiracetam group, and placebo group. The treatment period is 14 days, with a follow-up period of 90 days. The primary outcome measure is the change in the Loewenstein Occupational Therapy Cognitive Assessment score at 90 days after treatment. Secondary outcomes include changes in other cognitive assessments, neurological function, activities of daily living, and safety assessments.

Discussion

There is no robust evidence to suggest that l-oxiracetam and oxiracetam can enhance memory and cognitive function in patients with mild to moderate TBI. This study has the potential to answer this crucial clinical question.

Trial registration

chinadrugtrials.org.cn, identifier CTR20192539; ClinicalTrials.gov, identifier NCT04205565.

The Function of Spag6 to Repair Brain Edema Damage After Cerebral Ischemic Stroke-reperfusion

Sperm associated antigen 6 (Spag6) is the PF16 homolog of Chlamydomonas and participates in the regulation of cilia movement. Studies have shown that Spag6 is expressed in the brain, and its loss will lead to cerebral edema caused by a defect in motor cilium function in ependymal cells. However, it has not been reported whether the limited or extensive cerebral edema resulting from ischemic strokes is related to the expression regulation of Spag6. Therefore, this study aimed to investigate the effect and related mechanism of Spag6 in alleviating Cerebral Ischemic stroke-reperfusion (CIS/R) damage. Our experimental results showed that Spag6 overexpression alleviated CIS/R-mediated motor cilia structural disorder, improved cerebral edema, inhibited nerve injuries in rats with cerebral ischemia, and alleviated synaptic and dendritic spinal injuries by regulating the expressions of synaptic-related proteins such as CaMKII, PSD95, and CREB. Based on significant changes in PI3K/AKT-mTOR signaling pathway activity after CIS/R determination, we determined that Spag6 regulates the abnormal expression of CIS/R-induced inflammatory factors NF-κB, NLRP3, IL-10, and the autophagy-related proteins Beclin-1, LC3, and P62 by activating the PI3K/AKT-mTOR signaling pathway. This inhibits inflammation and autophagy in the brain tissue. In summary, this study revealed that Spag6 alleviates brain edema damage after CIS/R by maintaining the structural function of the motor cilium, regulating the PI3K/AKT-mTOR signaling pathway, and inhibiting inflammation and autophagy reaction.

Isoflurane Postconditioning Alleviates Ischemic Neuronal Injury Via MiR-384-5p Regulated Autophagy

The purpose of the study was to investigate the effect of isoflurane postconditioning on neuron injury in MCAO (middle cerebral artery occlusion) rats and its molecular mechanism of affecting autophagy through miR-384-5p/ATG5 (autophagy-related protein 5). HT22 cells (mouse hippocampal neuronal cell line) were exposed to 1.5% isoflurane for 30 min after OGD/R (oxygen-glucose deprivation/reoxygenation). Flow cytometry and CCK-8 kit were used to analyze changes in apoptosis and cell viability. The level of miR-384-5p was detected by qRT-PCR. Targetscan database prediction combined with dual luciferase reporter gene assay confirmed ATG5 as a target molecule downstream of miR-384-5p. In addition, western blot results confirmed that isoflurane postconditioning regulated miR-384-5p/ATG5 and significantly inhibited the expression of apoptosis-related proteins. Meanwhile, immunofluorescence staining for LC3II positivity combined with western blot results revealed that isoflurane postconditioning significantly inhibited autophagy. In vivo, MCAO induced neuronal injury for 90 min, followed by 24-h reperfusion. Isoflurane postconditioning (Iso) group underwent 1.5% isoflurane postconditioning for 60 min after reperfusion. Neurological scoring and TTC staining were used to evaluate the protective effect of isoflurane post-treatment on neurological injury, respectively. TUNEL staining and western blot results confirmed that isoflurane post-conditioning could regulate miR-384-5p and inhibit apoptosis. Immunofluorescence staining and western blot results confirmed that isoflurane post-conditioning inhibited autophagy in MCAO rats. Based on the above results, we speculated that the molecular mechanism of isoflurane post-conditioning to alleviate ischemic neuronal injury may be related to the regulation of miR-384-5p/ATG5-mediated autophagy.

Co-administration of Nanowired Oxiracetam and Neprilysin with Monoclonal Antibodies to Amyloid Beta Peptide and p-Tau Thwarted Exacerbation of Brain Pathology in Concussive Head Injury at Hot Environment

Environmental temperature adversely affects the outcome of concussive head injury (CHI)-induced brain pathology. Studies from our laboratory showed that animals reared at either cold environment or at hot environment exacerbate brain pathology following CHI. Our previous experiments showed that nanowired delivery of oxiracetam significantly attenuated CHI-induced brain pathology and associated neurovascular changes. Military personnel are the most susceptible to CHI caused by explosion, blasts, missile or blunt head trauma leading to lifetime functional and cognitive impairments affecting the quality of life. Severe CHI leads to instant death and/or lifetime paralysis. Military personnel engaged in combat operations are often subjected to extreme high or low environmental temperature zones across the globe. Thus, further exploration of novel therapeutic agents at cold or hot ambient temperatures following CHI are the need of the hour. CHI is also a major risk factor for developing Alzheimer's disease by enhancing amyloid beta peptide deposits in the brain. In this review, effect of hot environment on CHI-induced brain pathology is discussed. In addition, whether nanodelivery of oxiracetam together with neprilysin and monoclonal antibodies (mAb) to amyloid beta peptide and p-tau could lead to superior neuroprotection in CHI is explored. Our results show that co-administration of oxiracetam with neprilysin and mAb to AβP and p-tau significantly induced superior neuroprotection following CHI in hot environment, not reported earlier.

Rodent Models of Post-Stroke Dementia

Post-stroke cognitive impairment is one of the most common complications in stroke survivors. Concomitant vascular risk factors, including aging, diabetes mellitus, hypertension, dyslipidemia, or underlying pathologic conditions, such as chronic cerebral hypoperfusion, white matter hyperintensities, or Alzheimer’s disease pathology, can predispose patients to develop post-stroke dementia (PSD). Given the various clinical conditions associated with PSD, a single animal model for PSD is not possible. Animal models of PSD that consider these diverse clinical situations have not been well-studied. In this literature review, diverse rodent models that simulate the various clinical conditions of PSD have been evaluated. Heterogeneous rodent models of PSD are classified into the following categories: surgical technique, special structure, and comorbid condition. The characteristics of individual models and their clinical significance are discussed in detail. Diverse rodent models mimicking the specific pathomechanisms of PSD could provide effective animal platforms for future studies investigating the characteristics and pathophysiology of PSD.

Clinical Effects of Acupuncture for Stroke Patients Recovery

Stroke is assumed as one of the common cerebrovascular diseases that endangers human health and life. Its incidence and mortality rates are high, while survivors (50% to 70%) suffer from different degrees of disability. Hemiplegia is a common disability after stroke, mainly manifested as muscle weakness of the affected side, limb spasm, and limited activity, which severely impacts a patient's daily life. There are various rehabilitation methods for stroke hemiplegia, including modern rehabilitation medicine, motor therapy, acupuncture, and rehabilitation robot. The cost and effect of different rehabilitation methods are not the same. It is the focus to find an economical and effective rehabilitation method. In this paper, 128 stroke patients aged 41 to 73 hospitalized between January 2019 and January 2021 were analyzed. The intervention group used standard physical therapy and traditional acupuncture therapy, and the control group only used standard physical therapy. We used RStudio 1.1.419 (RStudio Corporation) for analysis. Experimental results show that the short-term efficacy of the intervention group is better than that of the control group. The intervention group was better than the control group in recovery from injury during rehabilitation, degree of muscle spasm, self-care ability in daily life, and overall degree of damage. In the long-term efficacy analysis, we can see that with the increase in the number of acupuncture, the efficacy of the intervention group is still better than that of the control group. Compared with physical rehabilitation alone, acupuncture has better short-term, and long-term clinical effects for stroke patients improves motor dysfunction and improves the quality of life and independence of stroke patients. With the increase in the number of acupuncture treatments, the patient's rehabilitation effect will be better.