Activation of GPR55 Ameliorates Maternal Separation-Induced Learning and Memory Deficits by Augmenting 5-HT Synthesis in the Dorsal Raphe Nucleus of Juvenile Mice.

Maternal separation (MS) represents a profound early life stressor with enduring impacts on neuronal development and adult cognitive function in both humans and rodents. MS is associated with persistent dysregulations in neurotransmitter systems, including the serotonin (5-HT) pathway, which is pivotal for mood stabilization and stress-coping mechanisms. Although the novel cannabinoid receptor, GPR55, is recognized for its influence on learning and memory, its implications on the function and synaptic dynamics of 5-HT neurons within the dorsal raphe nucleus (DRN) remain to be elucidated. In this study, we sought to discern the repercussions of GPR55 activation on 5-HT synthesis within the DRN of adult C57BL/6J mice that experienced MS. Concurrently, we analyzed potential alterations in excitatory synaptic transmission, long-term synaptic plasticity, and relevant learning and memory outcomes. Our behavioral assessments indicated a marked amelioration in MS-induced learning and memory deficits following GPR55 activation. In conjunction with this, we noted a substantial decrease in 5-HT levels in the MS model, while GPR55 activation stimulated tryptophan hydroxylase 2 synthesis and fostered the release of 5-HT. Electrophysiological patch-clamp analyses highlighted the ability of GPR55 activation to alleviate MS-induced cognitive deficits by modulating the frequency and magnitude of miniature excitatory postsynaptic currents within the DRN. Notably, this cognitive enhancement was underpinned by the phosphorylation of both NMDA and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors. In summary, our findings underscore the capacity of GPR55 to elevate 5-HT synthesis and modify synaptic transmissions within the DRN of juvenile mice, positing GPR55 as a promising therapeutic avenue for ameliorating MS-induced cognitive impairment.

Santacruzamate A Alleviates Pain and Pain-Related Adverse Emotions through the Inhibition of Microglial Activation in the Anterior Cingulate Cortex.

Chronic pain is a complex disease. It seriously affects patients' quality of life and imposes a significant economic burden on society. Santacruzamate A (SCA) is a natural product isolated from marine cyanobacteria in Panama. In this study, we first demonstrated that SCA could alleviate chronic inflammatory pain, pain-related anxiety, and depression emotions induced by complete Freund's adjuvant in mice while inhibiting microglial activation in the anterior cingulate cortex. Moreover, SCA treatment attenuated lipopolysaccharide (LPS)-induced inflammatory response by downregulating interleukin 1ß and 6 (IL-1ß and IL-6) and tumor necrosis factor-α (TNF-α) levels in BV2 cells. Furthermore, we found that SCA could bind to soluble epoxide hydrolase (sEH) through molecular docking technology, and the thermal stability of sEH was enhanced after binding of SCA to the sEH protein. Meanwhile, we identified that SCA could reduce the sEH enzyme activity and inhibit sEH protein overexpression in the LPS stimulation model. The results indicated that SCA could alleviate the development of inflammation by inhibiting the enzyme activity and expression of sEH to further reduce chronic inflammatory pain. Our study suggested that SCA could be a potential drug for treating chronic inflammatory pain.

Lotusine ameliorates propionic acid-induced autism spectrum disorder-like behavior in mice by activating D1 dopamine receptor in medial prefrontal cortex.

Autism spectrum disorder (ASD) is a multifaceted neuropsychiatric condition for which effective drug therapy for core clinical symptoms remains elusive. Lotusine, known for its neuroprotective properties in the treatment of neurological disorders, holds potential in addressing ASD. Nevertheless, its specific efficacy in ASD remains uncertain. This study aims to investigate the therapeutic potential of lotusine in ASD and elucidate the underlying molecular mechanisms. We induced an ASD mouse model through intracerebroventricular-propionic acid (ICV-PPA) injection for 7 days, followed by lotusine administration for 5 days. The efficacy of lotusine was evaluated through a battery of behavioral tests, including the three-chamber social test. The underlying mechanisms of lotusine action in ameliorating ASD-like behavior were investigated in the medial prefrontal cortex (mPFC) using whole-cell patch-clamp recordings, western blotting, immunofluorescence staining, molecular docking, and cellular thermal shift assay. The efficacy and mechanisms of lotusine were further validated in vitro. Lotusine effectively alleviated social deficits induced by ICV-PPA injection in mice by counteracting the reduction in miniature excitatory postsynaptic current frequency within the mPFC. Moreover, lotusine enhanced neuronal activity and ameliorated α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor dysfunction in ICV-PPA infusion mice by upregulating c-fos, p-GluA1 Ser 845, and p-GluA1 Ser 831 protein levels within the mPFC. Our findings also suggest that lotusine may exert its effects through modulation of the D1 dopamine receptor (DRD1). Furthermore, the rescuing effects of lotusine were nullified by a DRD1 antagonist in PC12 cells. In summary, our results revealed that lotusine ameliorates ASD-like behavior through targeted modulation of DRD1, ultimately enhancing excitatory synaptic transmission. These findings highlight the potential of lotusine as a nutritional supplement in the treatment of ASD.

Therapeutic Potential of Kaempferol against Sleep Deprivation-Induced Cognitive Impairment: Modulation of Neuroinflammation and Synaptic Plasticity Disruption in Mice.

Sleep deprivation (SD) has led to a rise in cognitive impairment (CI) cases. Kaempferol (KMP), known for its anti-inflammatory and antiapoptotic properties, holds promise in countering SD-induced CI. Experimental validation using a sleep-deprived CI model confirmed KMP's efficacy in mitigating CI. Immunofluorescence investigations emphasized diminished activation of astrocytes and reduced the proliferation of microglia in the hippocampus of mice subjected to SD. Subsequently, network pharmacological analyses were conducted and found that KMP may be closely related to the mitogen-activated protein kinase (MAPK) pathway in SD-induced CI. The influence of KMP on the MAPK pathway was verified by the observed decrease in the expression of phosphorylated JNK (p-JNK) and p38 (p-p38). Analyzing hippocampal AMPARS and NMDARS expression indicated KMP's ability to enhance GluA1 phosphorylation (Ser831 and Ser845) and GluN2A levels. Patch clamp assays demonstrated heightened excitatory transmitter transmission in the hippocampus, suggesting KMP's positive influence. Overall, KMP combats neuroinflammation via MAPK inhibition, augments synaptic function, and addresses learning and memory dysfunction in sleep-deprived mice.

Natural Shikonin Potentially Alters Intestinal Flora to Alleviate Acute Inflammation.

Shikonin, derived from the herb Lithospermum erythrorhizon (Purple Cromwell), is extensively utilized in traditional Chinese medicine as an anti-inflammatory agent; however, its effect on the intestinal flora is not yet known. Herein, we demonstrate that, compared to a blank control group, the intragastric administration of shikonin suppressed the swelling rate of ears in a mouse model of acute inflammation in a dose-dependent manner via animal experiments; furthermore, the 20 mg/kg shikonin treatment exhibited the highest inhibitory effect. In formal animal experimentation, we discovered that the inhibitory effect of shikonin with 20 mg/kg on inflammation was closely linked to the intestinal flora, whereby the microbiota phylum was altered in feces through a 16S rDNA sequencing analysis, implying that shikonin improves gut microbiota structures and compositions to counteract inflammation. Notably, using a real-time quantitative polymerase chain reaction (RT-qPCR), a Western blotting assay, and an immunohistochemistry (IHC) assay, we found that inflammatory cytokines such as TNF-α, IL-6, and IL-1ß reduced in both the shikonin-administration group and the positive control group than those in the blank control group, as expected. To the best of our knowledge, this is the first study to outline the underlying mechanism through which shikonin acts on gut microbes to alleviate acute inflammation, providing an alternative mechanism for shikonin to become a preventive agent in countering inflammation.

Luteolin in the Qi Bi Anshen decoction improves propionic acid-induced autism-like behavior in rats by inhibiting LRP1/MMP9.

BACKGROUND: A neurodevelopmental illness with a high frequency and unidentified pathophysiology is known as autism spectrum disorder (ASD). A research hotspot in this field is the identification of disease-specific biomarkers and drug intervention targets. Traditional Chinese medicine (TCM) can eliminate the symptoms of autism by precisely regulating human physiology. The Qi Bi Anshen decoction (QAT) is a commonly used TCM clinical drug commonly-used to treat for treating ASD. However, the primary active ingredients and underlying mechanisms of action of this decoction remain unknown. PURPOSE: This study aimed to investigate the active ingredients and pharmacodynamics of QAT in the treatment of ASD using a Sprague-Dawley rat model that resembled autism. METHODS: Autism-like rat models were established through intracerebroventricular injections of propionic acid (PPA). Subsequently, the rats were treated with QAT, and their efficacy was evaluated using the three-chamber method to analyze social interactions and grooming behavior. Additionally, open-field tests, elevated cross-maze tests, hematoxylin and eosin staining, Nissl staining, and enzyme-linked immunosorbent assays were performed; Western blot analysis was employed to determine the expression of synaptic plasticity-related proteins. Utilizing ultra-high-performance liquid chromatography-mass spectrometry (UPLC-MS), the effectiveness of active QAT components was assessed, and potential QAT targets were screened through molecular docking, surface plasmon resonance, and thermal migration experiments. To better understand the precise processes involved in treating ASD with active QAT components, in vivo and in vitro knockdown tests were also performed. RESULTS: QATexhibited a significant improvement in autism-like behavior and a notable increase in the production of proteins associated with synaptic plasticity. Furthermore, luteolin (LUT), identified as a potentially important active ingredient in QAT for treating ASD, reduced matrix metallopeptidase-9 (MMP9) expression. However, this effect was attenuated by the knockdown of low-density lipoprotein receptor-associated protein 1 (LRP1), which is the target binding site for LUT. CONCLUSIONS: LUT emerges as a potentially crucial active component of QAT in the treatment of ASD, with the ability to antagonize LRP1 and subsequently reduce MMP9 expression.

Network Pharmacology and Molecular Docking Analysis to Explore the Mechanism of Huaiqihuang-Mediated Alleviation of Henoch-Schönlein Purpura Nephritis.

Objective: Henoch-Schönlein purpura nephritis (HSPN) is considered a major cause of chronic renal failure and is the most common secondary glomerular disease in children. Huaiqihuang (HQH), a traditional Chinese herbal formula, exhibits therapeutic effects against HSPN in clinical practice. However, the potential molecular targets and mechanisms underlying HSPN treatment remain unclear. Methods: By constructing a protein-protein interaction (PPI) network, core targets related to HQH and HSPN were identified. Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathways were analyzed to identify the main pathways related to HSPN based on the core targets. To screen the main active ingredients of HQH against HSPN, an ingredient-target-pathway network was constructed using the top 10 main pathways associated with HSPN. Then, molecular docking was performed to explore the interactions and binding patterns between molecules and proteins. Results: Clinical data showed that HQH combined with conventional medicine significantly reduced 24-hour urine protein excretion, urine microalbumin levels, and erythrocyte counts in the urine sediment of HSPN patients. By constructing PPI models, 15 potential core targets were identified. The top 10 main pathways showed higher enrichment ratios, including the cytokine-cytokine receptor interaction and signaling pathways related to NOD-like receptor, IL-17, etc. Through the ingredient-target-pathway network and molecular docking, we revealed that five active ingredients of HQH had good affinities with three core targets, AKT1, MMP9, and SERPINE1, which may be vital in treating HSPN. Conclusions: The study preliminarily explored the active ingredients, targets, and pathways involved in HQH therapy for HSPN. The mechanism of HQH therapy may be attributed to the modulation of inflammatory response, immune response, and oxidative stress. Combined with clinical data, our results indicate that HQH is highly effective in treating HSPN.

Inhibitory effects of aloperine on voltage-gated Na+ channels in rat ventricular myocytes.

Aloperine (ALO), a quinolizidine alkaloid extracted from Sophora alopecuroides L., modulates hypertension, ventricular remodeling, and myocardial ischemia. However, few studies have evaluated the effects of ALO on other cardiovascular parameters. Accordingly, in this study, we used a rat model of aconitine-induced ventricular arrhythmia to assess the effects of ALO. Notably, ALO pretreatment delayed the onset of ventricular premature and ventricular tachycardia and reduced the incidence of fatal ventricular fibrillation. Moreover, whole-cell patch-clamp assays in rats' ventricular myocyte showed that ALO (3, 10, and 30 µM) significantly reduced the peak sodium current density of voltage-gated Na+ channel currents (INa) in a concentration-dependent manner. The gating kinetics characteristics showed that the steady-state activation and recovery curve were shifted in positive direction along the voltage axis, respectively, and the steady-state inactivation curve was shifted in negative direction along the voltage axis, i.e., which was similar to the inhibitory effects of amiodarone. These results indicated that ALO had anti-arrhythmic effects, partly attributed to INa inhibition. ALO may act as a class I sodium channel anti-arrhythmia agent.

Inhibitory effect of gallic acid on voltage-gated Na+ channels in rat cardiomyocytes.

Gallic acid (GA) has a protective effect on the cardiovascular system. To study its cardiac electrophysiological effects, voltage-gated Na+ channel currents (INa ) were recorded in rat cardiomyocytes using whole-cell patch clamp techniques. Moreover, the effects of GA on aconitine-induced arrhythmias were assessed using electrocardiograms in vivo. We found that the current-voltage characteristic curve (I-V curve) of INa significantly shifted in the presence of 1, 3, and 10 µmol/L of GA. The peak sodium current density (INa -Peak) was reduced from -84.02 ± 5.68 pA/pF to -65.78 ± 3.96 pA/pF with 1 µmol/L, -54.45 ± 5.18 pA/pF with 3 µmol/L, and -44.20 ± 4.35 pA/pF with 10 µmol/L, respectively. GA shifted the steady-state activation curve of INa and recovery curve to the right and the steady-state inactivation curve to the left. The observed inhibitory effect was comparable to that of amiodarone. GA pre-treatment significantly prolonged the onset of fatal ventricular fibrillation. Our results indicated that GA inhibited INa in rat ventricular myocytes and aconitine-induced arrhythmias in vivo. These results suggest the potential of GA for development as a novel anti-arrhythmic therapeutic.