Overexpression of miR-133b protects against isoflurane-induced learning and memory impairment

Kai-Xin-San ameliorates Alzheimer's disease-related neuropathology and cognitive impairment in APP/PS1 mice via the mitochondrial autophagy-NLRP3 inflammasome pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Kai-Xin-San (KXS) is a classic famous prescription that has been utilized for centuries to address dementia. New investigations have shown that the anti-dementia effect of KXS is connected with improved neuroinflammation. Nevertheless, the underlying mechanism is not well elucidated.

AIM OF THE STUDY

We propose to discover the ameliorative impact of KXS on Alzheimer's disease (AD) and its regulatory role on the mitochondrial autophagy-nod-like receptor protein 3 (NLRP3) inflammasome pathway.

MATERIALS AND METHODS

The Y maze, Morris water maze, and new objection recognition tests were applied to ascertain the spatial learning and memory capacities of amyloid precursor protein/presenilin 1 (APP/PS1) mice after KXS-treatment. Meanwhile, the biochemical indexes of the hippocampus were detected by reagent kits. The pathological alterations and mitochondrial autophagy in the mice' hippocampus were detected utilizing hematoxylin and eosin (H&E), immunohistochemistry, immunofluorescence staining, and transmission electron microscopy. Besides, the PTEN-induced putative kinase 1 (PINK1)/Parkin and NLRP3 inflammasome pathways protein expressions were determined employing the immunoblot analysis.

RESULTS

The results of behavioral tests showed that KXS significantly enhanced the AD mice' spatial learning and memory capacities. Furthermore, KXS reversed the biochemical index levels and reduced amyloid-β protein deposition in AD mice brains. Besides, H&E staining showed that KXS remarkably ameliorated the neuronal damage in AD mice. Concurrently, the results of transmission electron microscopy suggest that KXS ameliorated the mitochondrial damage in microglia and promoted mitochondrial autophagy. Moreover, the immunofluorescence outcomes exhibited that KXS promoted the expression of protein 1 light chain 3B (LC3B) associated with microtubule and the generation of autophagic flux. Notably, the immunofluorescence co-localization results confirmed the presence of mitochondrial autophagy in microglia. Finally, KXS promoted the protein expressions of the PINK1/Parkin pathway and reduced the activation of NLRP3 inflammasome. Most importantly, these beneficial effects of KXS were attenuated by the mitochondrial autophagy inhibitor chloroquine.

CONCLUSION

KXS ameliorates AD-related neuropathology and cognitive impairment in APP/PS1 mice by enhancing the mitochondrial autophagy and suppressing the NLRP3 inflammasome pathway.

Classic Famous Prescription Kai-Xin-San Ameliorates Alzheimer's Disease via the Wnt/β-Catenin Signaling Pathway

Kai-Xin-San (KXS) is a classic famous prescription composed of Polygalae Radix, Ginseng Radix et Rhizoma, Acori Tatarinowii Rhizoma, and Poria. Clinically, KXS is effective in treating amnesia and regulating cognitive dysfunction of Alzheimer's disease (AD), whereas its mechanism of action is still unclear. In this study, the AD model rats were established by combining intraperitoneal injection of D-galactose (150 mg/kg/day) and intracerebral injection of Aβ25-35 (10 μL) to investigate the meliorative effect of KXS on AD and explore its mechanism. After 1-month KXS treatment, Morris water maze test showed that different doses of KXS all improved the cognitive impairment of AD rats. The results of hematoxylin and eosin staining, Nissl staining, and Tunnel staining showed that the neuron injury in the hippocampal CA1 region of the AD rats was markedly improved after KXS treatment. Concurrently, KXS reversed the levels of biochemical indexes of AD rats. Furthermore, the protein expressions of Wnt1 and β-catenin in KXS groups were remarkably increased, while the expressions of Bax and caspase-3 were significantly decreased. Besides, KXS-medicated serum reduced the levels of tumor necrosis factor-α, interleukin-1β, and reactive oxygen species and regulated the protein expressions of β-catenin, glycogen synthase kinase-3β (GSK-3β), p-GSK-3β, Bax, and caspase-3 in Aβ25-35-induced pheochromocytoma cells. Most importantly, this effect was attenuated by the Wnt inhibitor IWR-1. Our results suggest that KXS improves cognitive and memory function of AD rats, and its neuroprotective mechanism may be mediated through the Wnt/β-catenin signaling pathway.

MicroRNA-133b Dysregulation in a Mouse Model of Cervical Contusion Injury

Our previous research studies have demonstrated the role of microRNA133b (miR133b) in healing the contused spinal cord when administered either intranasally or intravenously 24 h following an injury. While our data showed beneficial effects of exogenous miR133b delivered within hours of a spinal cord injury (SCI), the kinetics of endogenous miR133b levels in the contused spinal cord and rostral/caudal segments of the injury were not fully investigated. In this study, we examined the miR133b dysregulation in a mouse model of moderate unilateral contusion injury at the fifth cervical (C5) level. Between 30 min and 7 days post-injury, mice were euthanized and tissues were collected from different areas of the spinal cord, ipsilateral and contralateral prefrontal motor cortices, and off-targets such as lung and spleen. The endogenous level of miR133b was determined by RT-qPCR. We found that after SCI, (a) most changes in miR133b level were restricted to the injured area with very limited alterations in the rostral and caudal parts relative to the injury site, (b) acute changes in the endogenous levels were predominantly specific to the lesion site with delayed miR133b changes in the motor cortex, and (c) ipsilateral and contralateral hemispheres responded differently to unilateral SCI. Our results suggest that the therapeutic window for exogenous miR133b therapy begins earlier than 24 h post-injury and potentially lasts longer than 7 days.

Exercise-induced circulating exosomes potentially prevent pelvic organ prolapse in clinical practice via inhibition of smooth muscle apoptosis

Background

This study aimed to explore the potential mechanisms of exercise to prevent pelvic organ prolapse (POP) and search for diagnostic indictors for POP.

Methods

We used two clinical POP datasets with patients' information (GSE12852 and GSE53868), a dataset consisting of altered microRNA expression in circulating blood after exercise (GSE69717) for bioinformatic analysis and clinical diagnostic analysis, while a series of cellular experiments were conducted for preliminary mechanical validation.

Results

Our results show that AXUD1 is highly expressed in the smooth muscle of the ovary and is a key pathogenic gene in POP, while miR-133b is a key molecule in the regulation of POP by exercise-induced serum exosomes. The AUCs of AXUD1 for POP diagnosis were 0.842 and 0.840 in GSE12852 and GSE53868 respectively. At cut-off value = 9.627, the sensitivity and specificity of AXUD1 for predicating POP is 1.000 and 0.833 respectively for GSE53868, while at cut-off value = 3324.640, the sensitivity and specificity of AXUD1 for predicating POP is 0.941 and 0.812 separately for GSE12852. Analysis and experiments confirmed that miR-133b can directly regulate AXUD1. miR-133b mediated C2C12 myoblasts proliferation and inhibited hydrogen peroxide-induced apoptosis.

Conclusions

Our study proved that AXUD1 is a good clinical diagnostic indicator for POP and provided a theoretical basis for future prevention of POP through exercise and a potential target for intervention in muscle dysfunction.

MicroRNA-424-5p Alleviates Isoflurane Anesthesia-Induced Neurotoxicity in Human Embryonic Stem Cell-Derived Neurons by Targeting FASN

Isoflurane (ISO) is a type of anesthetic that might cause neurotoxicity in children. Although miR-424-5p is considerably downregulated in ISO-treated rat brain samples, its physiological role in ISO-induced neuronal injury in human embryonic stem cell-derived neurons remains unknown (hESC-derived neurons). miR-424-5p expression and fatty acid synthase (FASN) in ISO-treated hESC-derived neurons were tested via qRT-PCR. The amount of protein for Bax, Cleaved-caspase-8, Bcl-2, and FASN was investigated through western blot analysis. The viability and apoptosis of hESC-derived neurons were estimated through cell counting kit-8 assessment and TUNEL assay, accordingly. Superoxide dismutase, glutathione, and malondialdehyde levels were discovered via corresponding kits. The contents of inflammatory factors including interleukin-6 and tumor necrosis factor-α were examined by enzyme-linked immunosorbent assays. The combination between FASN and miR-424-5p was resolute via dual-luciferase reporter assessment. After exposure to ISO, induced neurotoxicity and a decreased miR-424-5p production were identified in hESC-derived neurons. Upregulation of miR-424-5p repressed ISO-induced apoptosis and mitigated ISO-induced inflammatory response and oxidative stress in vitro. FASN expression levels were reduced by elevation of miR-424-5p and upregulated after ISO treatment. Mechanically, FASN was directly targeted by miR-424-5p in hESC-derived neurons. Of note, the miR-424-5p elevation-suppressed neuronal apoptosis, inflammatory response, and oxidative stress were countered by upregulation of FASN.

MiR-128-3p Attenuates the Neurotoxicity in Rats Induced by Isoflurane Anesthesia

Isoflurane (ISO) has been widely used in clinical anesthesia, and exposure to ISO leads to cognitive dysfunction. Our paper aimed to investigate the effect of miR-128-3p on cognitive impairment, inflammation, and oxidative stress elicited by ISO anesthesia in Sprague-Dawley (SD) rats. The SD rats were treated with ISO to mimic the ISO-injured situation, and the concentration of miR-128-3p was quantified utilizing real-time PCR. The miR-128-3p's impacts in ISO-engendered rat models on the respects of inflammatory condition and oxidative activities were measured by the commercial kits. The Morris water maze test was adopted to measure the neuro-function regarding miR-128-3p. Additionally, the target was tested by the alternation of luciferase activity. The irritation of ISO suppressed miR-128-3p expression in rats, which was enhanced by the injection of miR-128-3p agomir. The adverse roles of ISO on inflammation, oxidative stress, and cognitive disorders were partially abrogated by an increment of miR-128-3p. A miR-128-3p's interconnection with specificity protein 1 (SP1) was pinpointed, and aggrandized mRNA levels of SP1 were found under ISO state. MiR-128 acted as a regulator in ISO damage in the respects of cognition, inflammation, and oxidative stress. The SP1's link of miR-128-3p was showcased.