Depressive-like behavior in mice recently recovered from motor disorders after 3-nitropropionic acid intoxication

Objective Striatum may be involved in depressive disorders according to the neuroimaging analysis and clinical data. However, no animal model at present supported the possible role of striatum in the pathogenesis of depression. In the present study, we have investigated the depressive-like behavior in mice recently intoxicated with 3-nitropropionic acid （3- NP）, a widely known toxin that selectively damages the striatum in the brain. Methods Mouse model was made with subacute systemic 3-NP treatment, and the depressive-like behavior was measured using the duration of immobility during forced swimming test （FST）. Results When the mice at day 15 post-intoxication just totally recovered from motor deficits, the duration of immobility in FST was significantly longer than that in controls. The depressive-like behavior was not due to the fatigue or general sickness following 3-NP intoxication and could be reversed by the antidepressant, desipramine hydrochloride. In two successive FST in 24 h interval, the depressive-like behavior could be observed again in subsequent FST （at day 16 post-intoxication）, and the mice presented a normal ＂learned helplessness＂. Conclusion A novel depression animal model could be established in mice during the initial period of recovery from 3-NP intoxication. The depression-like behavior might occur independently without involvement of cognitive defects, and the striatal lesions may underlie the depression-like behavior attributable to 3-NP intoxication.

Cerebral Ischemic Tolerance Induced by 3-nitropropionic Acid Is Associated with Increased Expression of Erythropoietin in Rats

Summary： To examine the changes in erythropoietin （Epo） protein and its mRNA expression in rat brain subjected to focal ischemia and possible mechanism of the preconditioning of mitochondrial toxin 3-nitropropionic acid （3-NPA）, rats were administrated either vehicle or 3-NPA at a dose of 20 mg/kg, intraperitoneally （ip）, 3 days prior to a 2-h middle cerebral artery occlusion followed by 24- h reperfusion. Infarct volumes were measured by using 2, 3, 5 triphenylte trazolinm chloride （TTC） staining, and Epo protein and its mRNA levels were assessed by immunohistochemistry and reverse transcriptase polymerase chain reaction （RT-PCR）, respectively. Our results showed that after reperfusion, Epo was found to be expressed extensively in the rat brain. It was most apparent in the basal nuclei and hippocampus, and was, to some extent, present in cortex. Preconditioning with 3-NPA caused a reduction in infarct volume. The expression of both Epo protein and mRNA increased significantly in the different brain areas in the 3-NPA pretreated group as compared with the non-pretreated ischemia model group. These results suggested that preconditioning with low dose 3-NPA could induce ischemic tolerance and neuro-protective effects by increasing the Epo expression in the ischemic and ischemia-related areas.

Chemical Preconditioning by 3-nitropropionic Acid Reduces Ischemia-reperfusion Injury in Rat Heart

Summary： This study was designed to investigate the cardioprotective effects of preconditioning with 3-nitropropionic acid, an inhibitor of mitochondrial succinate dehydrogenase. 16 isolated rat hearts were randomly divided into two groups, a treatment group and a control group. The rats of the treatment group were treated intraperitoneally with 3-nitropropionic ac;.d （3-NPA, 4 mg/kg） and the rats of the control group were treated with saline. 24 h after the treatment, the isolated hearts were mounted on a Langendorff apparatus. After 30 min, the hearts were subjected to 30min ischemia and 60-min reperfusion. The HR, LVDP and ±dp/dtmax were measured at preischemia and 30 min, 60 min after the reperfusion. Coronary effluent was collected 15 min after the reperfusion for the determination of CK and LDH. At the end of the 60-min reperfusion the heart was removed for the determination of myocardial SOD and MDA. Our results showed that in the 3-NPA group LVDP and ±dp/dt recovered significantly better, myocardial MDA, CK and LDH were significantly lower and the myocardial SOD was significantly higher than in the control group. It is concluded that chemical preconditioning by 3-nitropropionate has cardioprotective effects against ischemia-reperfusion injury.

Involvement of Apoptosis in 3-nitropropionic Acid-induced Ischemic Tolerance to Transient Focal Cerebral Ischemia in Rats

The involvement of apoptosis in mitochondrial toxin 3 nitropropionic acid (3 NPA) induced ischemic tolerance to transient focal cerebral ischemia in rats and the mechanism was investigated. 3 NPA at a dose of 20 mg/kg or vehicle control was intraperitoneally into the rats. Three days later, rats were exposed to 2 h of middle cerebral artery occlusion followed by 24 h of reperfusion. Infarct volumes were assessed by 2,3,5 triphenyltetrazolinm chloride (TTC) staining 24 h after reperfusion. Neural cell apoptosis in cerebral ischemic penumbra was detected by terminal deoxynucleotidyl transferase mediated dUTP biotin in situ nick end labeling (TUNEL) and flow cytometry methods (FCM). The results showed that as compared to the vehicle treated group, pretreatment with 3 NPA could reduce the infarct volume by 23.3 % and decrease the number of TUNEL positive neural cells and apoptotic percentage by 47 % ( P< 0.05) and 44.9 % ( P< 0 01), respectively. It was concluded that the development of 3 NPA induced ischemic tolerance in brain might be related to the decreases in neural cell apoptosis.

The spatial and temporal relationship between oxidative stress and neuronal degeneration in 3-nitropropionic acid model

The current study investigates the role of oxidative stress and calcium homeostasis in the development of selective striatal lesions in metabolic impairment model caused by 3-nitropropionic acid (3NP). In this report, we examined the distribution of oxidative stress markers and the production of mitochondrial reactive oxygen species in the presence of 3NP in male Sprague-Dawley rats. Protein oxidation was assessed using 3-nitrotyrosine immunoreactivity, while DNA oxidative damage was evaluated by poly (ADP-ribose) polymerase-1 activity. The Reactive Oxygen Species (ROS) production was determined in isolated mitochondrial from striatum and cerebellum of two age groups following 3NP and variable calcium concentration. The results demonstrate that increased 3-nitro-tyrosine level is the most robust in the striatum and the least evident in the cerebellum following 4 days of 3NP treatment. No significant change in the levels of poly ADP-ribosylated proteins was observed, likely due to a rapid PARP-1 cleavage as detected by the appearance of 50 kDa necrotic fragment. In mitochondrial isolates, there was no immediate increase in mitochondrial ROS following 3NP in either striatum or cerebellum;however, calcium addition resulted in a concentration dependent increase in reactive oxygen species in striatal mitochondria of the older animals. These results suggest that in aging, mitochondria become more susceptible to the generation of ROS in conditions that cause a concurrent compromised in mitochondrial calcium concentration. This finding implicates mitochondria dysfunction as a key cellular target in pathological states that are associated with metabolic impairment. The results also reinforce the notion that mitochondrial function in the striatum and cerebellum respond differently to the aging process, which may explain the variable regional vulnerability in 3NP model.

No spatial memory deficit exists in Kunming mice that recently recovered from motor defects following 3-nitropropionic acid intoxication

Objective Numerous studies have described both motor defects and cognitive impairments in several strains of rodents following 3-nitropropionic acid （3-NP） intoxication. In the present study, we investigated spatial recognition memory in Kunming mice that just recovered from motor defects induced by 3-NP. Methods Mouse model was made by systemic subacute 3-NP treatment, and spatial recognition memory was measured through the Y-maze Test, a simple two-trial recognition test. Results （1） On day 15 following 3-NP treatment, affected Kunming mice did not show motor defects in the Rotarod test and presented normal gait again. （2） In the following Y-maze test after lh interval, the percentage （90.0%） of mice showing novel ann preference in 3-NP treatment group was significantly higher than the random chance level （50%）, although it was only slightly higher than that （83.3%） in control group. On day 45 after 3-NP treatment, mice failed to choose unfamiliar novel arm as first choice, and the same occured in the control group. （3） For both post-intoxicated （on day 15 and day 45 following 3-NP treatment） and control groups, the duration in the novel ann and the frequency of entering it, were longer and higher compared with familiar start and other arms. For these mice that recently recovered from motor defects following 3-NP intoxication, no spatial memory deficits were observed through Y-maze Test. Conclusion Kunming mice used in our assays might possess resistance to cognitive impairment induced by 3-NP, which is consistent with previous findings in Swiss EPM-M1 mice.

3-Nitropropionic acid modifies neurotrophin mRNA expression in the mouse striatum: 18S-rRNA is a reliable control gene for studies of the striatum

Objective The aim of the present study was to determine the changes in the mRNA levels of neurotrophins and their receptors in the striatal tissue of mice treated with 3-nitropropionic acid （3-NP）. Methods At 1 and 48 h after the last drug administration, the mRNA expression of nerve growth factor, brain-derived neurotrophic factor, neurotrophin-3 and neurotrophin-4/5 as well as their receptors p75, TrkA, TrkB and TrkC, was evaluated using semi-quantitative （semi- Q） and real-time RT-PCR. β-actin mRNA and ribosomal 18S （18S rRNA） were tested as internal controls. Results 3-NP treatment did not affect mRNA expression of all neurotrophins and their respective receptors equally. Also, differences in neurotrophin and receptor mRNA expression were observed between semi-Q and real-time RT-PCR. Real-time RT-PCR was more accurate in evaluating the mRNA expression of the neurotrophins than semi-Q, and 18S rRNA was more reliable than β-actin as an internal control. Conclusion Neurotrophins and their receptors expression is differentially affected by neuronal damage produced by inhibition of mitochondrial respiration with 3-NP treatment in low, sub-chronic doses in vivo.

Involvement of CYP347W1 in neurotoxin 3-nitropropionic acid-based chemical defense in mustard leaf beetle Phaedon cochleariae

Chrysomelina beetlesstore 3-nitropropionic acid in form of a pretoxin,isoxazolin-5-one glucoside-conjugated ester,to protect themselves against predators.Here we identified a cytochrome P450 monooxygenase,CYP347W1,to be involved in the production of the 3-nitropropionic acid moiety of the isoxazolin-5-one glucoside ester.Knocking down CYP347W1 led to a significant depletion in the concentration of the isoxazolin-5-one glucoside ester and an increase in the concentration of the isoxazolin-5-one glucoside in the larval hemolymph.Enzyme assays with the heterologously expressed CYP347W1 showed freeβ-alanine was not the direct substrate.Homology modeling indicated thatβ-alanine-CoA ester can fit into CYP347W1’s active site.Furthermore,we proved that Phaedon cochleariae eggs are not able to de novo synthesize 3-NPA,although both isoxazolin-5-one glucoside and its 3-NPA-conjugated ester are present in the eggs.These results provide direct evidence for the involvement of CYP347W1 in the biosynthesis of a P.cochleariae chemical defense compound.

Maternal supplementation with n-3 fatty acids affects placental lipid metabolism, inflammation, oxidative stress, the endocannabinoid system, and the neonate cytokine concentrations in dairy cows

Background The placenta plays a crucial role in supporting and influencing fetal development.We compared the effects of prepartum supplementation with omega-3(n-3)fatty acid(FA)sources,flaxseed oil(FLX)and fish oil(FO),on the expression of genes and proteins related to lipid metabolism,inflammation,oxidative stress,and the endocannabinoid system(ECS)in the expelled placenta,as well as on FA profile and inflammatory response of neonates.Late-pregnant Holstein dairy cows were supplemented with saturated fat(CTL),FLX,or FO.Placental cotyledons(n=5)were collected immediately after expulsion,and extracted RNA and proteins were analyzed by RTPCR and proteomic analysis.Neonatal blood was assessed for FA composition and concentrations of inflammatory markers.Results FO increased the gene expression of fatty acid binding protein 4(FABP4),interleukin 10(IL-10),catalase(CAT),cannabinoid receptor 1(CNR1),and cannabinoid receptor 2(CNR2)compared with CTL placenta.Gene expression of ECS-enzyme FA-amide hydrolase(FAAH)was lower in FLX and FO than in CTL.Proteomic analysis identified 3,974 proteins;of these,51–59 were differentially abundant between treatments(P≤0.05,|fold change|≥1.5).Top canonical pathways enriched in FLX vs.CTL and in FO vs.CTL were triglyceride metabolism and inflammatory processes.Both n-3 FA increased the placental abundance of FA binding proteins(FABPs)3 and 7.The abundance of CNR1 cannabinoid-receptor-interacting-protein-1(CNRIP1)was reduced in FO vs.FLX.In silico modeling affirmed that bovine FABPs bind to endocannabinoids.The FLX increased the abundance of inflammatory CD44-antigen and secreted-phosphoprotein-1,whereas prostaglandin-endoperoxide synthase 2 was decreased in FO vs.CTL placenta.Maternal FO enriched neonatal plasma with n-3 FAs,and both FLX and FO reduced interleukin-6 concentrations compared with CTL.Conclusion Maternal n-3 FA from FLX and FO differentially affected the bovine placenta;both enhanced lipid metabolism and modulated oxidative stress,however,FO increased some transcriptional ECS components,possibly related to the increased FABPs.Maternal FO induced a unique balance of pro-and anti-inflammatory components in the placenta.Taken together,different sources of n-3 FA during late pregnancy enhanced placental immune and metabolic processes,which may affect the neonatal immune system.

Traditional Chinese medicine Pien-Tze-Huang ameliorates LPS-induced sepsis through bile acid-mediated activation of TGR5-STAT3-A20 signalling

Pien Tze Huang(PZH),a class-1 nationally protected traditional Chinese medicine(TCM),has been used to treat liver diseases such as hepatitis;however,the effect of PZH on the progression of sepsis is unknown.Here,we reported that PZH attenuated lipopolysaccharide(LPS)-induced sepsis in mice and reduced LPS-induced production of proinflammatory cytokines in macrophages by inhibiting the activation of mitogen-activated protein kinase(MAPK)and nuclear factor-kappa B(NF-κB)signalling.Mechanistically,PZH stimulated signal transducer and activator of transcription 3(STAT3)phosphorylation to induce the expression of A20,which could inhibit the activation of NF-κB and MAPK signalling.Knockdown of the bile acid(BA)receptor G protein-coupled bile acid receptor 1(TGR5)in macrophages abolished the effects of PZH on STAT3 phosphorylation and A20 induction,as well as the LPS-induced inflammatory response,suggesting that BAs in PZH may mediate its anti-inflammatory effects by activating TGR5.Consistently,deprivation of BAs in PZH by cholestyramine resin reduced the effects of PZH on the expression of phosphorylated-STAT3 and A20,the activation of NF-κB and MAPK signalling,and the production of proinflammatory cytokines,whereas the addition of BAs to cholestyramine resin-treated PZH partially restored the inhibitory effects on the production of proinflammatory cytokines.Overall,our study identifies BAs as the effective components in PZH that activate TGR5-STAT3-A20 signalling to ameliorate LPS-induced sepsis.

Ferulic acid reduces inflammatory response induced by radiation through Sirt1-NLRP3 pathway

Objective:A model of inflammatory damage was induced by radiation to investigate whether ferulic acid(FA)can reduce the inflammatory response through the Sirt1-NLRP3 inflammatory pathway.This will help discover radiation-protective drugs and elucidate the molecular mechanisms related to radiation-induced inflammatory damage.Methods:A mouse model of radiation-induced immunoinflammatory injury was established to verify the anti-inflammatory effects of FA in vivo.C57BL/6J mice were randomly divided into six groups,and 5 Gy whole-body irradiation was used for modeling.Mice were administered a gastric solvent,amifostine,or 25,50,or 100 mg/kg FA daily for 12 days,consecutively,before irradiation.The serum of mice was collected 24 hour after irradiation to observe the content of inflammatory factors interleukin(IL)-1β,IL-18,IL-6,and tumor necrosis factor(TNF)-α.The spleen and thymus tissues of mice were weighed and the organ index was calculated for pathological testing and immunofluorescence detection.Results:FA reduced the radiation-induced decrease in the spleen and thymus indices.FA significantly reduced the secretion of inflammatory factors in the serum and reversed the radiation-induced reduction in lymphocytes in the spleen and thymus of mice.FA activated Sirt1 and inhibited the expression of the NLRP3 inflammasome to alleviate the inflammatory response.Conclusions:FA reduced radiation-induced inflammation in animals,possibly by activating Sirt1 and reducing nucleotide oligomerization domain(NOD)-like receptor thermal protein domain associated protein 3(NLRP3)inflammasome expression,thereby reducing the secretion of inflammatory factors.

Landscape of Sequence Variations in Homologous Copies of FAD2 and FAD3 in Rapeseed(Brassica napus L.)Germplasm with High/Low Linolenic Acid Trait

Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har-bors four and six homologous copies,respectively,of the two fatty acid desaturases FAD2 and FAD3,which con-trol the last two steps of ALA biosynthesis during seed oil accumulation.In this study,we compared their promoters,coding sequences,and expression levels in three high-ALA inbred lines 2006L,R8Q10,and YH25005,a low-ALA line A28,a low-ALA/high-oleic-acid accession SW,and the wildtype ZS11.The expression levels of most FAD2 and FAD3 homologs in the three high-ALA accessions were higher than those in ZS11 and much higher than those in A28 and SW.The three high-ALA accessions shared similar sequences with the pro-moters and CDSs of BnFAD3.C4 and BnFAD3.A3.In A28 and SW,substitution of three amino acid residues in BnFAD2.A5 and BnFAD2.C5,an absence of BnFAD2.C1 locus,and a 549 bp long deletion on the BnFAD3.A3 promoter were detected.The profile of BnFAD2 mutation in the two low-ALA accessions A28 and SW is different from that reported in previous studies.The mutations in BnFAD3 in the high-ALA accessions are reported for thefirst time.In identifying the sites of these mutations,we provide detailed information to aid the design of mole-cular markers for accelerated breeding schemes.

Acetic acid additive in NaNO_(3)aqueous electrolyte for long-lifespan Mg-air batteries

Mg-air batteries have attracted tremendous attention as a potential next-generation power source for portable electronics and e-transportation due to their remarkable high theoretical volumetric energy density,environmental sustainability,and cost-effectiveness.However,the fast hydrogen evolution reaction(HER)in NaCl-based aqueous electrolytes impairs the performance of Mg-air batteries and leads to poor specific capacity,low energy density,and low utilization.Thus,the conventionally used NaCl solute was proposed to be replaced by NaNO_(3)and acetic acid additive as a corrosion inhibitor,therefore an electrolyte engineering for long-life time Mg-air batteries is reported.The resulting Mg-air batteries based on this optimized electrolyte demonstrate an improved discharge voltage reaching~1.8 V for initial 5 h at a current density of 0.5 mA/cm^(2) and significantly prolonged cells'operational lifetime to over 360 h,in contrast to only~17 h observed in NaCl electrolyte.X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry were employed to analyse the composition of surface film and scanning electron microscopy combined with transmission electron microscopy to clarify the morphology changes of the surface layer as a function of acetic acid addition.The thorough studies of chemical composition and morphology of corrosion products have allowed us to elucidate the working mechanism of Mg anode in this optimized electrolyte for Mg-air batteries.

Catalytic Performance of Aquathermolysis and Viscosity Reduction of Heavy Oil over a WO_(3)/ZrO_(2) Solid Acid

Tungstated zirconia(WO_(3)/ZrO_(2))solid acid catalysts with different WO_(3) contents were prepared by a hydrothermal method and then used in the catalytic aquathermolysis of heavy oil from Xinjiang.The WO_(3)/ZrO_(2) solid acid catalyst was characterized by a range of characterization methods,including X-ray diffraction,NH3-temperature programmed desorption,and pyridine infrared spectroscopy.The WO_(3) content of the WO_(3)/ZrO_(2) catalysts had an important impact on the structure and property of the catalysts.When the WO_(3) mass fraction was 20%,it facilitated the formation of tetragonal zirconia,thereby enhancing the creation of robust acidic sites.Acidity is considered to have a strong impact on the catalytic performance of the aquathermolysis of heavy oil.When the catalyst containing 20%WO_(3) was used to catalyze the aquathermolysis of heavy oil under conditions of 14.5 MPa,340℃,and 24 h,the viscosity of heavy oil decreased from 47266 to 5398 mPa·s and the viscosity reduction rate reached 88.6%.The physicochemical properties of heavy oil before and after the aquathermolysis were analyzed using a saturates,aromatics,resins,and asphaltenes analysis,gas chromatography,elemental analysis,densimeter etc.After the aquathermolysis,the saturate and aromatic contents significantly increased from 43.3%to 48.35%and 19.47%to 21.88%,respectively,with large reductions in the content of resin and asphaltene from 28.22%to 25.06%and 5.36%to 2.03%,respectively.The sulfur and nitrogen contents,and the density of the oil were significantly decreased.These factors were likely the main reasons for promoting the viscosity reduction of heavy oil during the aquathermolysis over the WO_(3)/ZrO_(2) solid acid catalysts.

Elaidic acid-induced intestinal barrier damage led to gut-liver axis derangement and triggered NLRP3 inflammasome in the liver of SD rats

Previous studies have shown that trans fatty acids(TFA) are associated with several chronic diseases,the gut microbiota is directly influenced by dietary components and linked to chronic diseases.Our research investigated the effects of elaidic acid(EA),a typical TFA,on the gut microbiota to understand the underlying mechanisms of TFA-related chronic diseases.16S rDNA gene sequencing on faecal samples from Sprague-Dawley rats were performed to explore the composition change of the gut microbiota by EA gavage for 4 weeks.The results showed that the intake of EA increased the abundance of well-documented harmful bacteria,such as Proteobacteria,Anaerotruncus,Oscillibacter and Desulfovibrionaceae.Plus,EA induced translocation of lipopolysaccharides(LPS) and the above pathogenic bacteria,disrupted the intestinal barrier,led to gut-liver axis derangement and TLR4 pathway activation in the liver.Overall,EA induced intestinal barrier damage and regulated TLR4-MyD88-NF-κB/MAPK pathways in the liver of SD rats,leading to the activation of NLRP3 inflammasome and inflammatory liver damage.

Oleanolic acid inhibits colon cancer cell stemness and reverses chemoresistance by suppressing JAK2/STAT3 signaling pathway

Background:Oleanolic acid(OA),a pentacyclic triterpenoid exhibiting specific anti-cancer properties and highly effective antioxidant activity,was isolated from traditional Chinese medicinal herbs.Conversely,the OA that impacts colon cancer(CC)cells and its underlying mechanisms remain poorly understood.Methods:The cytotoxic effect of OA alone or OA-5-Fluorouracil(5-FU)combination on normal and CC cells was analyzed by methyl thiazolyl diphenyl-tetrazolium bromide(MTT).Then,the impact of OA on CC cell lines(LoVo and HT-29)proliferation and stemness were measured using colon formation and tumorsphere formation assays.Octamer-binding transcription factor 4(Oct4),Prominin-1(CD133),Nanog,and transcription factor SOX-2(SOX2)are cell stemness-related indicators whose expression was assessed usingfluorescence qPCR assay,Western blotting,and immunohistochemistry.The effect of OA on the proliferative potency of CC cells was evaluated using an in vivo model.Results:The stem-like characteristics and clone production of colon cancer cells were markedly reduced by OA alone or in combination with OA-5-FU.Moreover,OA increases the susceptibility of CC cells to 5-FU by blocking the cell stemness-related markers(CD133,Nanog,SOX2,and Oct4)expression levels both in vitro and in vivo,as well as by inactivating the activator of transcription 3(STAT3 signaling)and Janus kinase 2/signal transducer(JAK2).Conclusion:Thesefindings imply that oleanolic acid,both in vitro and in vivo,suppresses the JAK2/STAT3 pathway,which in turn reverses chemoresistance and decreases colon cancer cell stemness.Therefore,by reducing the recommended amount of 5-FU,this strategy may improve chemotherapeutic effectiveness and minimize undesired side effects.

Gossypol acetic acid regulates leukemia stem cells by degrading LRPPRC via inhibiting IL-6/JAK1/STAT3 signaling or resulting mitochondrial dysfunction

BACKGROUND Leukemia stem cells(LSCs)are found to be one of the main factors contributing to poor therapeutic effects in acute myeloid leukemia(AML),as they are protected by the bone marrow microenvironment(BMM)against conventional therapies.Gossypol acetic acid(GAA),which is extracted from the seeds of cotton plants,exerts anti-tumor roles in several types of cancer and has been reported to induce apoptosis of LSCs by inhibiting Bcl2.AIM To investigate the exact roles of GAA in regulating LSCs under different microenvironments and the exact mechanism.METHODS In this study,LSCs were magnetically sorted from AML cell lines and the CD34+CD38-population was obtained.The expression of leucine-rich pentatricopeptide repeat-containing protein(LRPPRC)and forkhead box M1(FOXM1)was evaluated in LSCs,and the effects of GAA on malignancies and mitochondrial RESULTS LRPPRC was found to be upregulated,and GAA inhibited cell proliferation by degrading LRPPRC.GAA induced LRPPRC degradation and inhibited the activation of interleukin 6(IL-6)/janus kinase(JAK)1/signal transducer and activator of transcription(STAT)3 signaling,enhancing chemosensitivity in LSCs against conventional chemotherapies,including L-Asparaginase,Dexamethasone,and cytarabine.GAA was also found to downregulate FOXM1 indirectly by regulating LRPPRC.Furthermore,GAA induced reactive oxygen species accumulation,disturbed mitochondrial homeostasis,and caused mitochondrial dysfunction.By inhibiting IL-6/JAK1/STAT3 signaling via degrading LRPPRC,GAA resulted in the elimination of LSCs.Meanwhile,GAA induced oxidative stress and subsequent cell damage by causing mitochondrial damage.CONCLUSION Taken together,the results indicate that GAA might overcome the BMM protective effect and be considered as a novel and effective combination therapy for AML.

超声波辅助合成色酮-3-甲酸

以苯酚为原料,经傅克酰基化、甲酰化、水解三步反应制备了色酮-3-甲酸,总收率57.4%,产物纯度98.6%。甲酰化反应以3-(2-羟基苯基)-3-氧代丙酸甲酯0.05 mol为模型,考察了不同溶剂、甲酸钠用量、超声频率、超声功率、反应温度、反应时间的影响。研究结果表明最优化的反应条件为四氢呋喃作溶剂、甲酸钠与3-(2-羟基苯基)-3-氧代丙酸甲酯的用量摩尔比为1.5:1、超声频率50 kHz、超声功率550 W、温度60℃、反应11 h,该步反应收率为80.0%。

老年肌少症患者血清硬骨素和n-3脂肪酸表达水平及临床价值研究

目的探讨血清硬骨素、n-3脂肪酸在老年肌少症患者中的表达水平及临床意义。方法收集2021年5月—2023年5月新疆医科大学第五附属医院老年病科收治的老年肌少症患者118例为病例组,根据病情程度分为肌少症前期(n=39)、肌少症期(n=46)和重度肌少症期(n=33),选取同期医院健康体检者60例为健康对照组。酶联免疫吸附法检测血清硬骨素,气相色谱法检测n-3脂肪酸水平;人体成分分析仪和生物电阻抗体法检测体脂百分比、上臂围、内脏脂肪面积、蛋白质质量;6M步行法测量步速,Jamar握力计测量双手握力,双能X线吸收仪测量全身及四肢骨骼肌质量,计算相对四肢骨骼肌质量指数(RSMI);硬骨素和n-3脂肪酸与病情严重程度及上述指标的相关性用Pearson积矩相关或Spearman秩相关分析;采用Logistic回归分析老年肌少症的影响因素,ROC曲线评估血清硬骨素和n-3脂肪酸对老年肌少症的诊断价值。结果病例组患者血清硬骨素、n-3脂肪酸水平低于健康对照组(t/P=13.342/<0.001、13.116/<0.001);血清硬骨素、n-3脂肪酸水平比较,肌少症前期>肌少症期>重度肌少症期(F/P=59.138/<0.001、79.217/<0.001);病例组患者体脂百分比、内脏脂肪面积大于健康对照组(t/P=8.732/<0.001、5.124/<0.001),上臂围、蛋白质质量、步速、握力、全身骨骼肌质量、四肢骨骼肌质量、RSMI水平低于健康对照组(t/P=3.859/<0.001、8.459/<0.001、5.758/<0.001、12.492/<0.001、7.006/<0.001、10.334/<0.001、11.813/<0.001);老年肌少症患者血清硬骨素、n-3脂肪酸与体脂百分比、内脏脂肪面积呈负相关(硬骨素:r/P=-0.537/<0.001、-0.612/<0.001;n-3脂肪酸:r/P=-0.498/<0.001、-0.523/<0.001),与上臂围、蛋白质质量、步速、握力、全身骨骼肌质量、四肢骨骼肌质量、RSMI呈正相关(硬骨素:r/P=0.593/<0.001、0.624/<0.001、0.639/<0.001、0.597/<0.001、0.601/<0.001、0.607/<0.001、0.638/<0.001;n-3脂肪酸:r/P=0.569/<0.001、0.611/<0.001、0.570/<0.001、0.592/<0.001、0.549/<0.001、0.534/<0.001、0.587/<0.001);年龄、体脂百分比、内脏脂肪面积升高是老年肌少症危险因素[OR(95%CI)=1.702(1.115~2.600)、1.551(1.052~2.287)、1.387(1.006~1.913)],BMI、上臂围、蛋白质质量、步速、握力、全身骨骼肌质量、四肢骨骼肌质量、RSMI、硬骨素、n-3脂肪酸升高是老年肌少症的保护因素[OR(95%CI)=0.728(0.539~0.982)、0.768(0.593~0.995)、0.845(0.723~0.986)、0.815(0.668~0.995)、0.585(0.382~0.897)、0.746(0.573~0.972)、0.733(0.559~0.964)、0.713(0.541~0.940)、0.822(0.695~0.973)、0.803(0.664~0.971)];血清硬骨素、n-3脂肪酸及二者联合诊断老年肌少症的AUC分别为0.822、0.818、0.894,二者联合诊断老年肌少症的AUC大于其各自单独诊断(Z=2.205、2.328,P=0.002、0.001)。结论老年肌少症患者血清硬骨素和n-3脂肪酸降低,两指标与病情严重程度密切相关,早期联合检测可辅助临床诊断老年肌少症。

基于PI3K/AKT/GSK-3β信号通路探讨EA改善APP/PS1双转基因小鼠认知功能障碍的内在机制

目的探讨鞣花酸(ellagicacid,EA)对APP/PS1双转基因小鼠认知功能的影响,并基于磷脂酰肌醇3-激酶/蛋白激酶B/糖原合成酶激酶-3(PI3K/AKT/GSK-3β)信号通路探讨鞣花酸对双转基因小鼠海马氧化应激水平的调节机制。方法将32只SPF级6月龄APP/PS1双转基因小鼠随机分为4组,即APP/PS1组、APP/PS1+EA组、APP/PS1+LY294002组、APP/PS1+EA+LY294002组,每组8只,另外选取8只SPF级C57BL/6J野生型小鼠(Wildtype)作为空白对照组,即WT组。APP/PS1+EA组给予50mg·kg^(-1)·d^(-1)灌胃EA;APP/PS1+LY294002组予以1.5mg·kg^(-1)·d^(-1)腹腔注射PI3K抑制剂LY294002;APP/PS1+EA+LY294002组予以50mg·kg^(-1)·d^(-1)灌胃EA,同时按1.5mg·kg^(-1)·d^(-1)腹腔注射LY294002;WT组和APP/PS1组于相同时间点灌胃等体积10%二甲基亚砜(DMSO)。每日给药1次,连续给药60天。Morris水迷宫检测小鼠学习和记忆能力,免疫组化、蛋白免疫印迹法检测PI3K、AKT、GSK-3β相关蛋白的表达,透射电镜观察小鼠海马组织超微结构变化。结果与WT组相比,其他四组的逃避潜伏期均增长(P<0.05),穿越平台次数明显减少(P<0.01);APP/PS1组、APP/PS1+LY294002组和APP/PS1+EA+LY294002组中的PI3K、AKT蛋白表达量显著降低(P<0.01),GSK-3β表达量显著升高(P<0.01);APP/PS1+EA组的PI3K表达量降低(P<0.05),AKT表达量显著降低(P<0.01),GSK-3β表达量升高(P<0.05);与WT组相比,APP/PS1组海马神经元细胞数目较少,线粒体结构破坏,大部分线粒体出现肿胀,线粒体的内膜和外模不完整,部分线粒体嵴消失,微管、微丝缠结,排列紊乱,而APP/PS1+EA组神经元细胞数较APP/PS1组增多,线粒体结构较清晰,可见清楚的线粒体嵴,线粒体轻度水肿。微管、微丝排列较整齐有序。结论鞣花酸改善AD模型小鼠的学习和记忆能力、减少海马神经元细胞损伤和凋亡,其作用机制可能是通过调节PI3K、AKT、GSK-3β等相关蛋白降低AD模型小鼠海马氧化应激水平。