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@#[Objective] To investigate the evolution of inflammation under conditions and the effects of ginsenosides on macrophages subjected to the simulated weightlessness, with the aim of mitigating the inflammation. [Methods] Initially, genes related to weightlessness, inflammation, and immunity were identified in the GeneCards database. Then, Search Tool for the Retrieval of Interaction Gene/Proteins (STRING) protein network analysis was conducted to determine the core targets involved in the weightlessness-induced inflammation. Subsequently, Label-Free Quantitative (LFQ) proteomics was carried out to discern the distinctive genes within ginsenoside-treated Tohoku Hospital Pediatrics-1 (THP-1) cells. Next, utilizing the outcomes of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses, the biological processes and signaling pathways in which ginsenosides predominately engaged were scrutinized, and the primary targets of ginsenosides in combating weightlessness-induced inflammation were examined. Finally, enzyme-linked immunosorbent assay (ELISA) was performed to detect the secretion levels of interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor (TNF)-α from lipopolysaccharide (LPS)-induced THP-1 cells under simulated weightlessness conditions, as well as during the weightlessness recovery period following treatment with ginsenosides. [Results] A total of 2 933 genes associated with inflammation, 425 genes linked to weightlessness, and 4 564 genes connected to immunity were retrieved from the GeneCards database. Protein-protein interaction (PPI) networks were generated to identify pivotal targets associated with weightlessness-induced inflammation such as IL-1β, IL-6, TNF, and albumin (ALB). It was found that ginsenosides primarily participated in the regulation of various inflammationrelated signaling pathways and pathways related to pathogenic microorganism infections. Moreover, it has a significant impact on the expression of proteins such as cluster of differentiation 40 (CD40), IL-1β, and poly ADP-ribose polymerase 1 (PARP1). As revealed in the simulated weightlessness cell test, ginsenosides exhibited a remarkable capacity to attenuate the secretion of inflammatory factors, specifically IL-6 and TNF-α (P < 0.000 1), in THP-1 macrophages following induction by LPS under simulated weightlessness conditions. In addition, it reduced the secretion of IL-1β, IL-6, IL-8, and TNF-α (P < 0.000 1) during the weightlessness recovery phase [Conclusion] Weightlessness can disrupt several inflammation-related signaling pathways, but ginsenosides were shown to mitigate the release of various inflammatory factors in macrophages subjected to simulated weightlessness, thereby exerting a protective role against inflammation. This study has laid a theoretical groundwork for further exploring the potential application of ginsenosides in safeguarding against LPS induced inflammation in a weightlessness environment.
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OBJECTIVE Microgravity exerts several negative effects on the learning and memory of astro-nauts during space flight.Rg1 and Rb1,the key steroidal components of ginseng,have shown potent neuroprotec-tive effects with a high safety profile.The object of the current study is to investigate the influence of Rg1 and Rb1 on simulated microgravity-induced memory and learning dysfunction in the hindlimb suspension(HLS)rat model.METHODS The HLS rats were orally administered Rg1(30 and 60 μmol·kg-1)or Rb1(30 and 60 μmol·kg-1)for four weeks.The Morris water maze test(MWM)and reward operating conditioning reflex test(ROCR)were conducted to evaluate spatial and associative learning and memory.After the behavior tests,the serum and the prefrontal cortex(PFC)were dissected to measure the mechanism.RESULTS Rg1 and Rb1 treatment amelio-rated the cognitive deficits of HLS-exposure rats in MWM and ROCR,reduced reactive oxygen species generation and increased antioxidant enzyme activity.Rg1 and Rb1 also assisted in the recovery of mitochondrial complex Ⅰ(NADH dehydrogenase)activities and Mfn2,and decrea-sed Drp-1 expression.Furthermore,Rg1 and Rb1 reduced the ratio of Bax/Bcl-2 and the expression of cleaved-cas-pase 3,cytochrome c,increased the levels of SYN,PSD95 and activated BDNF-TrkB/PI3K-Akt pathway in the PFC.CONCLUSION Rg1 and Rb1 treatment attenuated cog-nitive deficits induced by HLS,mitigated mitochondrial dysfunction,attenuated oxidative stress,inhibited apopto-sis,and increased the synaptic plasticity,which was partly mediated by the modulation of the BDNF-TrkB/PI3K-Akt signaling.
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Objective:To investigate the changes of gene or protein expression and activity of matrix metalloprotein9 (MMP9) and tissue inhibitor ofmetalloproteinasel (TIMP1) in the carotid artery (CA) of 4 wk hindlimb unweighted rat.Methods:A 4 weeks(wk) hindlimb unweighted (HU) rat model was used to simulate the effect of weightlessness on the cardiovascular system.Transmission electron microscopy was used to detect the content of ECM.Reverse transcriptase polymerase chain reaction(RT-PCR) was conducted to measure the mRNA content MMP and TIMP1.Immunohistochemistry and Western blot technique were used to measure the protein abundance.Gelatin zymography was carried out to detect the activity of MMP9.Results:Compared to the control group (CON),the area of ECM was enhanced (P＜0.05) and the content of collage fiber was increased (P＜0.05) in the CA of HU rats;moreover,HU did not affect the mRNA expression of MMP9,but significantly reduced the protein content (P＜0.05) or enzymatic activity (P＜0.05).Accordingly,the mRNA or protein expression of TIMP1 in the CA was significantly increased by HU (P＜0.05).Conclusion:Simulated weightlessness caused imbalance between MMP and TIMP1 expression,which might contribute to the ECM aggregation and stiffness of CA.
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Objective To observe the different characteristics of spontaneous activitiy after simulated weightlessness 21 days in rats , aimed to provide a evaluation method for space weightlessness induced function change in human beings and to provide a reference for researches on the astronauts protective measures .Methods 30 Wistar male rats were randomly divided into three groups , the control group , the sham tail-suspended hindlimb unloading group ( the sham group ) , the tail-suspended hindlimb unloading group ( the suspending group ) , ten animals in each group .All animals were placed in the simulated space flight environmental equipment which has a real -time monitor system for 21 days.During the 21 days, the intake of water , food and the body weight were measured every week .Meanwhile, five independent activity data were collect every day , for example, morning(8:00am~12:00am), afternoon(2:00pm~6:00pm), daytime(8:00am~8:00pm),night(8:00pm~8:00am),and whole day (8:00am ~8:00am).Results The spontaneous activity of normal rats in the control group between morning and afternoon had no significant difference , but it is significantly between night and daytime .The movement time and distance in night are 2 -3 times than that of the daytime.After 10 days of tail suspending , the circadian rhythm was disordered , and the spontaneous activity in day and night become more similar in rats of the suspending group .Because of the individual difference , the spontaneous activity is not stable at the first 10 days in rats of the sham group , but after 10 days, it become close to the control group .Conclusion Rat is nocturnal animal and sleeps in the daytime , the spontaneous activity in night is 2 -3 times as compared with the daytime.The sham tail-suspended hindlimb unloading 21 days can not influence the circadian rhythm in rats .Tail suspending 21 days will caused to the disappearance in the circadian rhythm in rats .
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This study investigated the tight junction (TJ) protein expression of the intestinal mucosa in a rat tail-suspension model under simulated weightlessness.Twenty-four Wistar rats were randomly divided into three groups:CON group (n=8),control; SUS-14 d group (n=8),tail-suspension for 14 days;SUS-21 d group (n=8),tail-suspension for 21 days.Occludin and Zonula Occluden-1 (ZO-1) expression levels were determined by immunohistochemical analysis and mRNA fluorescent quantitative PCR.Plasma levels of diamine oxidase (DAO) and d-lactate were determined using enzymatic spectrophotometry.Immunohistochemical results for occludin and ZO-1 showed disruption of the TJs in the intestinal mucosa in SUS-14 d and SUS-21 d groups.The expression levels of occludin and ZO-1 in SUS-21 d group were lower than those in SUS-14 d group,and significantly lower than those in CON group (Occldin:0.86±0.02 vs 1.01±0.03 vs 1.63±0.03 and ZO-1:0.82±0.01 vs 1.00±0.02 vs 1.55±0.01,P＜0.01).Moreover,the levels of plasma DAO and d-lactate in SUS-21 d group were higher than those in SUS-14 d group,and significantly higher than those in CON group (DAO:27.58±0.49 vs 20.74±0.49 vs 12.94±0.21 and d-lactate:37.86±0.74 vs 28.26±1.01 vs 17.76±0.91,P＜0.01).There were significant negative co rrelations between occludin or ZO-1 expression levels and DAO (r2=0.9014,r2=0.9355,P＜0.01) or d-lactate levels (r2=0.8989,r2=0.9331,P＜0.01).Occludin and Zo-1 were reduced in intestinal mucosa both in mRNA and protein levels in the rat tail-suspension model.The significant negative correlations between expression levels of TJs and plasma levels of DAO or d-lactate support the hypothesis that intestinal permeability is increased due to a decrease in TJ protein expression during tail-suspension from 14 days to 21 days.
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Objective To study the effects of simulated weightlessness induced by tail-suspension on reproduction in adult male rats and its mechanisms. Methods Twenty Spraque-Dawley adult male rats were randomly divided into two groups: the experimental group and control group. Rats in the experimental group were tail-suspended for 14 days. After the treatment, the weight and morphology of testis, the quantity and quality of sperm, the level of serum testosterone and the apoptosis rate of testicular cells were observed. Results Compared with the control, the testicular weight, the quantity and quality of sperm, the level of serum testosterone significantly decreased (P＜0.05) while the apoptosis rate of testicular cells significantly increased (P＜0.05) in tail-suspended rats. In addition, hematoxylin and eosin (HE) staining showed that seminiferous tubules atrophied, spermatogenic cells decreased, seminiferous epithelial cells disintegrated and shed, and the lumina were azoospermic. Conclusion Simulated weightlessness induced by tail-suspension has a harmful effect on male reproduction of adult rats by increasing the apoptosis of testicular cells.
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Objective To study the morphological changes of soleus muscle spindle and electrical activity of neurons in Red Nucleus(RN) of the rat after 2 weeks' simulated weightlessness, and to reveal the interaction between proprioceptive inputs of muscle spindles and reciprocal alterations in RN under simulated weightlessness. Methods Twenty female rats were exposed to weightlessness simulated by tail-suspension for 14 days (SW-14d). Body weight(200-220g) matched female rats were control group(Con). The morphological changes in isolated muscle spindle of soleus muscle, the discharges of red nucleus neurons were observed after 14d tail-suspensions by silver staining and extracellular recording respectively. Results Compared with control group ,the nerve ending of muscle spindle in SW-14d was distorted, degenerated and dissolved; the diameters of intrafusal fibers and capsule in equatorial region of soleus muscle spindles were diminished(P＜0.05). The spontaneous cell activity and discharge of RN neurons (spikes/s) induced by afferent firing from muscle spindles after injection of succinylcholine were reduced after 2 weeks' simulated weightlessness respectively (18.44±5.96 vs. 10.19±6.88, 32.50±8.08 vs. 16.86±5.97, P＜0.01). Conclusion The degeneration of muscle spindle induced by simulated weightlessness may be one of the causes that led to alterations in discharges of RN.
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Objective To investigate the effect of hindlimb unloaded 3 weeks on bone mineral density of different parts in simulated weightlessness rats,and the effect of Chinese herbal prescriptions on them.Methods 2-month-old male Wistar rats were randomly divided into 3 groups:control group(CON),hindlimb unloading group(HU),HU+Chinese herbal prescription group(HUC).During the whole experiment(4 weeks),HUC were given Chinese herbal prescriptions(contains Radix Acanthopanacis Senticosl,Radix Rehmanniae Praeparata,Radix Achyranthis Bidentatae,Concha Ostreae,etc),while CON and HU were given equal measures Concha Ostreae prepared by acetic acid.After 1 week of adaption period,weightlessness was simulated by tail suspension in HU and HUC for three weeks.Rats were executed at the end of the fourth week and bone mineral density of 7 differernt parts were determined.BMD of skull bone and second thoracic vertebra were examined by buoyancy method,and fourth lumbar vertebra,humerus,femur,radio-ulna and tibia were examined by bone densitometer.Results Compared with CON,BMD of skull of HU increased significantly(P 0.05),but BMD of lumbar vertebra,femur and tibia were decreased notably(P 0.05).Conclusions The change of hindlimb unloaded 3 weeks on systemic BMD presented certain trend.BMD of skull bone increased,little change on upper limbs and second thoracic vertebra,and fourth lumbar vertebra and hind limbs reduced.Chinese herbal prescriptions had the function to relieve weightlessness osteoporosis,and had positive effect on calcium distribution with weightlessness.
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Objective To study the effects of Chinese medicine compound on bone density, biomechanics, histomorphometry of weightlessness rats simulated by tail suspension. Methods Fifty Wistar rats were randomly divided into 5 groups with 10 rats each group:control group, model group, and low dose, medium dose and high dose Chinese medicine compound treated suspension group, the experiment period was 21 days. BMD of femur and lumbar vertebrae were detected by dual energy X-ray absorptiometry. The femoral biomechanics parameters and anti-compress ability of lumbar vertebrae were measured by three-point assay and compress test respectively. The quantitative structures of non- decalcified bone tissue sections were analyzed by histomorphometry. Result Compared with control group, BMD of femur and lumbar of model group decreased remarkably (P
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Objective To observe the effects of different doses of Sijunzi decoction(SJZD) on soleus(SOL) atrophy in tail-suspended rats.Methods Weightlessness was simulated by tail suspension in female Sprague-Dawley rats.Six rats in each group were assigned to a 5-group design randomly: control(CON);hind limb unloading(HLU) plus intragastric water instillation(HLU-W),as well as plus intragastric high dose(HLU-H),middle dose(HLU-M) and low dose(HLU-L) SJZD instillation respectively.Immunohistochemical method was used to observe the effects of them on expression of myosin heavy chain(MHC) isoforms in soleus muscle.Results Compared with HLU-W,muscle wet weight(MWW) of SOL in high and middle dose group increased by 33.11%and 37.57%respectively,as well as no significant difference with CON;three doses of SJZD groups increased the percentage of type Ⅰ myosin by 34.04%~54.90% and its cross sectional area(CSA) by 8.50%~36.86%,moreover SJZD of middle dose group showed no significant difference with that of CON group.Conclusion Three doses of SJZD groups can significantly prevent soleus atrophy induced by simulated weightlessness,and middle dose is the more effective one than high and low dose.
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Objective To study the effect of Chinese herb medicine compound on general state and bone-muscle system in simulated weightlessness rats, and to observe the synergistic action of other ingredients in the compound on calcium. Methods Thirty Wistar rats were divided into 3 groups:control group, tail suspend group, tail suspend and medicine group which were given Chinese herb medicine compound by intragastric administration. After 3 weeks simulated weightlessness, body weight (BW), muscle weight (MW) and index (MI) of posterior limb, bone length (BL), wet weight (BWW), index (BI), dry weight (BDW), content of organic (ORG) and inorganic (INO) substance, bone mineral density (BMD), and mechanical properties (MEC) of femur were observed. Results At the middle-later stage of the experiment, BW of tail suspend group decreased significantly (P
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To investigate the changes of cell apoptosis genes in pulmonary tissue of tail suspended rats during simulated weightlessness, 40 Spragno Dawley male rats were divided into 4 groups: suspended for 7d,control of 7d, suspended for 21d, and control of 21d.Tail suspension(-30?) was used as weightlessness simulation.The condition of bcl 2/bax in pulmonary tissues was detected by in situ hybridization. The results showed that the level of bcl 2 mRNA in pulmonary tissue of 7d tail suspended rats decreased significantly( P 0 05). The results also showed that the level of bax mRNA in pulmonary tissue of 7d tail suspended rats increased significantly( P 0 05).It can be concluded that there are certain changes of cell apoptosis genes in pulmonary tissue of 7d tail suspended rats during simulated weightlessness.
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To investigate the changes of vascular endothelial growth factor mRNA (VEGFmRNA) in pulmonary tissues of tail suspended rats during simulated weightlessness,the experiments were conducted on 40 Spragno Dawley male rats,divided into 4 groups:suspended for 7d,control of 7d and suspended for 21d,control of 21d.Tail suspension(-30?) was used as weightlessness simulation.The condition of VEGFmRNA in pulmonary tissues was examined by hybridization in situ. The results showed that the level of VEGFmRNA in pulmonary tissues of 7d tail suspended rats increased significantly( P