Inflammation is involved in cerebral ischemia/reperfusion (I/R)-induced neurological damage. Saikosaponin A (SSa), extracted from Radix bupleuri, has been reported to exert anti-inflammatory effects. This article aimed to investigate whether SSa could ameliorate neuroinflammation mediated by ischemic stroke and the underlying mechanism.
Rat middle cerebral artery occlusion (MCAO) model was employed in this study, and the cognitive and motor functions were detected by behavioral tests. Inflammatory cytokines in the serum were detected by ELISA kits. The expression levels of Toll-like receptor 4 (TLR4), nuclear factor-kappa B (NF-κB), and high-mobility group box 1 (HMGB1) in the brain tissues were assayed with Western blot.
Our results showed that SSa pretreatment could significantly reduce brain damage, improve neurological function recovery, and decrease the water content of brain tissues when compared with the model group. SSa pretreatment significantly reduced the serum HMGB1 level and downregulated the contents of inflammatory cytokines including tumor necrosis factor-α, interleukin-1 beta, and interleukin-6. Furthermore, SSa pretreatment could attenuate the decreased TLR4 and nucleus NF-κB in the brain of MCAO rats. The protein level of HMGB1 in the nucleus was significantly upregulated in the SSa pretreatment group.
Our results suggested that the pretreatment with SSa provided significant protection against cerebral I/R injury in rats via its anti-inflammation property by inhibiting the nucleus HMGB1 release.
Sevoflurane, a volatile anesthetic, is known to induce widespread neuronal degeneration and apoptosis. Recently, the stress-inducible protein sestrin 2 and adenosine monophosphate-activated protein kinase (AMPK) have been found to regulate the levels of intracellular reactive oxygen species (ROS) and suppress oxidative stress. Notoginsenoside R1 (NGR1), a saponin isolated from Panax notoginseng, has been shown to exert neuroprotective effects. The effects of NGR1 against neurotoxicity induced by sevoflurane were assessed.
Sprague-Dawley rat pups on postnatal day 7 (PD7) were exposed to sevoflurane (3%) anesthesia for 6 h. NGR1 at doses of 12.5, 25, or 50 mg/kg body weight was orally administered to pups from PD2 to PD7.
Pretreatment with NGR1 attenuated sevoflurane-induced generation of ROS and reduced apoptotic cell counts. Western blotting revealed decreased cleaved caspase 3 and Bad and Bax pro-apoptotic protein expression. NGR1 substantially upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) expression along with increased heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase-1 levels, suggesting Nrf2 signaling activation. Enhanced sestrin-2 and phosphorylated AMPK expression were noticed following NGR1 pretreatment.
This study revealed the neuroprotective effects of NGR1 through effective suppression of apoptosis and ROS via regulation of apoptotic proteins and activation of Nrf2/HO-1 and sestrin 2/AMPK signaling cascades.
Reversible splenial lesion syndrome (RESLES) is a single-stage non-specific syndrome with unclear pathogenesis. There has been no report on answer delay in patients with RESLES. We report a female patient who was admitted to our department for mixed aphasia accompanied by cognitive impairment. During the rapid improvement of aphasia, there was a clear phase of language output response delay accompanied by resolution of imaging lesions. We analyzed the course and the examination results of the patient and speculated the cause and pathogenesis. RESLES-relevant knowledge was systematically reviewed, which will help doctors in the classification of cerebral function and the diagnosis of RESLES. The specific language and cognitive impairment may be associated with the damage of contact fibers in the bilateral primary and secondary sensory and motor cortices.
The aim of this study is to investigate the dysbiosis characteristics of gut microbiota in patients with cerebral infarction (CI) and its clinical implications.
Stool samples were collected from 79 CI patients and 98 healthy controls and subjected to 16S rRNA sequencing to identify stool microbes. Altered compositions and functions of gut microbiota in CI and its correlation with clinical features were investigated. Random forest and receiver operating characteristic analysis were used to develop a diagnostic model.
Microbiota diversity and structure between CI patients and healthy controls were overall similar. However, butyrate-producing bacteria (BPB) were significantly reduced in CI patients, while lactic acid bacteria (LAB) were increased. Genetically, BPB-related functional genes were reduced in CI patients, whereas LAB-related genes were enhanced. The interbacterial correlations among BPB in CI patients were less prominent than those in healthy controls. Clinically, BPB was negatively associated with the National Institutes of Health Stroke Scale (NIHSS), while LAB was positively correlated with NIHSS. Both BPB and LAB played leading roles in the diagnostic model based on 47 bacteria.
The abundance and functions of BPB in CI patients were significantly decreased, while LAB were increased. Both BPB and LAB displayed promising potential in the assessment and diagnosis of CI.
Local field potentials (LFPs) are involved in almost all cognitive activities of animals. Several kinds of recording electrodes are used for recording LFPs in freely moving animals, including commercial and homemade electrodes. However, commercial recording electrodes are expensive, and their relatively fixed size often causes a steric hindrance effect, especially when combining deep brain stimulation (DBS) with LFP recording, which may not always satisfy the aim of researchers. Currently, an increasing number of researchers are designing their own recording electrodes to lower research costs. Nevertheless, there is no simple universal method to produce low-cost recording electrodes with a specific size according to the target brain area. Thus, we developed a simple method for quickly producing low-cost multiple-channel recording electrodes. To inspect the effectiveness of our self-designed electrode, LFPs were recorded in a Parkinson’s disease (PD) rat model, and an electrical stimulation electrode was implanted into the subthalamic nucleus to verify the space-saving ability of the self-designed recording electrode. The results showed that <30 min was needed to prepare an electrode and that the electrode materials cost <5 dollars. Further investigations showed that our electrode successfully recorded the beta oscillations (12–40 Hz) in the PD rat model. Thus, this method will greatly reduce the cost of recording electrodes and save time for researchers. Additionally, the small size of the electrode will further facilitate DBS research.
Most research has mainly focused on the decline of the subjective experience in Alzheimer’s disease (AD). However, few attempts have been made to evaluate whether subjective experience may be maintained in AD. In this narrative review, we attempt to provide a positive view, according to which patients with AD can enjoy, to some extent, subjective experience during memory retrieval. Memory and expression difficulties (e.g., aphasia) limit the ability of patients with AD to describe their memories, resulting in a little specificity of reported memories. However, according to the “authentic subjective experience” view, we propose in this study that the ability to mentally relive these memories could be preserved in the patients. By proposing the authentic subjective experience view, we attempt to provide an alternative view to the general consideration that the patients suffer a diminished subjective experience. This view can contribute to a larger clinical framework that gives a positive meaning to the subjective experience of patients with AD. Furthermore, several clinical and empirical implications can be drawn from the authentic subjective experience view, including the possibility to evaluate behavioral correlates of the subjective experience in AD.
The purpose of this study was to quantify head motion between isometric erector spinae (ES) contraction strategies, paradigms, and intensities in the development of a neuroimaging protocol for the study of neural activity associated with trunk motor control in individuals with low back pain. Ten healthy participants completed two contraction strategies; (1) a supine upper spine (US) press and (2) a supine lower extremity (LE) press. Each contraction strategy was performed at electromyographic (EMG) contraction intensities of 30, 40, 50, and 60% of an individually determined maximum voluntary contraction (MVC) (±10% range for each respective intensity) with real-time, EMG biofeedback. A cyclic contraction paradigm was performed at 30% of MVC with US and LE contraction strategies. Inertial measurement units (IMUs) quantified head motion to determine the viability of each paradigm for neuroimaging. US vs LE hold contractions induced no differences in head motion. Hold contractions elicited significantly less head motion relative to cyclic contractions. Contraction intensity increased head motion in a linear fashion with 30% MVC having the least head motion and 60% the highest. The LE hold contraction strategy, below 50% MVC, was found to be the most viable trunk motor control neuroimaging paradigm.
Obesity and the brain are linked since the brain can control the weight of the body through its neurotransmitters. The aim of the present study was to investigate the effect of high-fat diet (HFD)-induced obesity on brain functioning through the measurement of brain glutamate, dopamine, and serotonin metabolic pools. In the present study, two groups of rats served as subjects. Group 1 was fed a normal diet and named as the lean group. Group 2 was fed an HFD for 4 weeks and named as the obese group. Markers of oxidative stress (malondialdehyde, glutathione, glutathione-s-transferase, and vitamin C), inflammatory cytokines (interleukin [IL]-6 and IL-12), and leptin along with a lipid profile (cholesterol, triglycerides, high-density lipoprotein, and low-density lipoprotein levels) were measured in the serum. Neurotransmitters dopamine, serotonin, and glutamate were measured in brain tissue. Fecal samples were collected for observing changes in gut flora. In brain tissue, significantly high levels of dopamine and glutamate as well as significantly low levels of serotonin were found in the obese group compared to those in the lean group (P > 0.001) and were discussed in relation to the biochemical profile in the serum. It was also noted that the HFD affected bacterial gut composition in comparison to the control group with gram-positive cocci dominance in the control group compared to obese. The results of the present study confirm that obesity is linked to inflammation, oxidative stress, dyslipidemic processes, and altered brain neurotransmitter levels that can cause obesity-related neuropsychiatric complications.