Effects of improved amino acid balance diet on lysine mammary utilization, whole body protein turnover and muscle protein breakdown on lactating sows

Background The study objective was to test the hypothesis that low crude protein(CP)diet with crystalline amino acids(CAA)supplementation improves Lys utilization efficiency for milk production and reduces protein turnover and muscle protein breakdown.Eighteen lactating multiparous Yorkshire sows were allotted to 1 of 2 isocaloric diets(10.80 MJ/kg net energy):control(CON;19.24%CP)and reduced CP with“optimal”AA profile(OPT;14.00%CP).Sow body weight and backfat were recorded on d 1 and 21 of lactation and piglets were weighed on d 1,14,18,and 21 of lactation.Between d 14 and 18,a subset of 9 sows(CON=4,OPT=5)was infused with a mixed solution of 3-[methyl-2H3]histidine(bolus injection)and[13C]bicarbonate(priming dose)first,then a constant 2-h[13C]bicarbonate infusion followed by a 6-h primed constant[1-13C]lysine infusion.Serial blood and milk sampling were performed to determine plasma and milk Lys enrichment,Lys oxidation rate,whole body protein turnover,and muscle protein breakdown.Results Over the 21-d lactation period,compared to CON,sows fed OPT had greater litter growth rate(P<0.05).Compared to CON,sows fed OPT had greater efficiency of Lys(P<0.05),Lys mammary flux(P<0.01)and whole-body protein turnover efficiency(P<0.05).Compared to CON,sows fed OPT tended to have lower whole body protein breakdown rate(P=0.069).Muscle protein breakdown rate did not differ between OPT and CON(P=0.197).Conclusion Feeding an improved AA balance diet increased efficiency of Lys and reduced whole-body protein turnover and protein breakdown.These results imply that the lower maternal N retention observed in lactating sows fed improved AA balance diets in previous studies may be a result of greater partitioning of AA towards milk rather than greater body protein breakdown.

γ-Aminobutyric acid alleviates litchi thaumatin-like protein-induced inflammation and reduces gut microbial translocation

Previous research reported litchi thaumatin-like protein(LcTLP)could lead to inflammation,which is a factor causing the adverse reactions after excessive intake of litchi.As a main amino acid in litchi pulp,γ-aminobutyric acid(GABA)was found with anti-inflammatory effect.Therefore,this study aimed to investigate the effects of GABA on LcTLP-induced inflammation through RAW264.7 macrophages and C57BL mice models.In vitro study showed GABA could effectively regulate the level of inflammatory cytokines(interleukin(IL)-1β,IL-6,IL-10,and prostaglandin E2)and Ca2+in cells,and inhibit the phosphorylation of p65,IκB,p38,c-Jun N-terminal kinase(JNK)and extracellular signal-regulated kinase(ERK).These results indicate GABA alleviated inflammation through nuclear factor-κB and mitogen-activated protein kinase pathway signaling pathways.In vivo experiment was performed to verify the anti-inflammatory effect of GABA,and the results demonstrated that GABA reduced the inflammation and oxidative stress in the liver of LcTLP-treated mice,as it down-regulated the pro-inflammatory cytokines,malondialdehyde,aspartate transferase,and alanine transaminase.The relative expression of phosphorylated p38,JNK and ERK in mice liver with GABA treatment were reduced to 65%,39%and 80%of the control group,respectively.Furthermore,GABA treatment enriched probiotic bacteria and decreased pathogenic bacteria in mice gut,which reveals GABA could effectively reduce the translocation of gut microbiota.

Low crude protein formulation with supplemental amino acids for its impacts on intestinal health and growth performance of growing-finishing pigs

Background Low crude protein(CP)formulations with supplemental amino acids(AA)are used to enhance intestinal health,reduce costs,minimize environmental impact,and maintain growth performance of pigs.However,extensive reduction of dietary CP can compromise growth performance due to limited synthesis of non-essential AA and limited availability of bioactive compounds from protein supplements even when AA requirements are met.Moreover,implementing a low CP formulation can increase the net energy(NE)content in feeds causing excessive fat deposition.Additional supplementation of functional AA,coupled with low CP formulation could further enhance intestinal health and glucose metabolism,improving nitrogen utilization,and growth performance.Three experiments were conducted to evaluate the effects of low CP formulations with supplemental AA on the intestinal health and growth performance of growing-finishing pigs.Methods In Exp.1,90 pigs(19.7±1.1 kg,45 barrows and 45 gilts)were assigned to 3 treatments:CON(18.0%CP,supplementing Lys,Met,and Thr),LCP(16.0%CP,supplementing Lys,Met,Thr,Trp,and Val),and LCPT(16.1%CP,LCP+0.05%SID Trp).In Exp.2,72 pigs(34.2±4.2 kg BW)were assigned to 3 treatments:CON(17.7%CP,meeting the requirements of Lys,Met,Thr,and Trp);LCP(15.0%CP,meeting Lys,Thr,Trp,Met,Val,Ile,and Phe);and VLCP(12.8%CP,meeting Lys,Thr,Trp,Met,Val,Ile,Phe,His,and Leu).In Exp.3,72 pigs(54.1±5.9 kg BW)were assigned to 3 treatments and fed experimental diets for 3 phases(grower 2,finishing 1,and finishing 2).Treatments were CON(18.0%,13.8%,12.7%CP for 3 phases;meeting Lys,Met,Thr,and Trp);LCP(13.5%,11.4%,10.4%CP for 3 phases;meeting Lys,Thr,Trp,Met,Val,Ile,and Phe);and LCPG(14.1%,12.8%,11.1%CP for 3 phases;LCP+Glu to match SID Glu with CON).All diets had 2.6 Mcal/kg NE.Results In Exp.1,overall,the growth performance did not differ among treatments.The LCPT increased(P<0.05)Claudin-1 expression in the duodenum and jejunum.The LCP and LCPT increased(P<0.05)CAT-1,4F2hc,and B0AT expressions in the jejunum.In Exp.2,overall,the VLCP reduced(P<0.05)G:F and BUN.The LCP and VLCP increased(P<0.05)the backfat thickness(BFT).In Exp.3,overall,growth performance and BFT did not differ among treatments.The LCPG reduced(P<0.05)BUN,whereas increased the insulin in plasma.The LCP and LCPG reduced(P<0.05)the abundance of Streptococcaceae,whereas the LCP reduced(P<0.05)Erysipelotrichaceae,and the alpha diversity.Conclusions When implementing low CP formulation,CP can be reduced by supplementation of Lys,Thr,Met,Trp,Val,and Ile without affecting the growth performance of growing-finishing pigs when NE is adjusted to avoid increased fat deposition.Supplementation of Trp above the requirement or supplementation of Glu in low CP formulation seems to benefit intestinal health as well as improved nitrogen utilization and glucose metabolism.

Fatty acid binding protein 5 is a novel therapeutic target for hepatocellular carcinoma

BACKGROUND Hepatocellular carcinoma(HCC)is an aggressive subtype of liver cancer and is one of the most common cancers with high mortality worldwide.Reprogrammed lipid metabolism plays crucial roles in HCC cancer cell survival,growth,and evolution.Emerging evidence suggests the importance of fatty acid binding proteins(FABPs)in contribution to cancer progression and metastasis;however,how these FABPs are dysregulated in cancer cells,especially in HCC,and the roles of FABPs in cancer progression have not been well defined.AIM To understand the genetic alterations and expression of FABPs and their associated cancer hallmarks and oncogenes in contributing to cancer malignancies.METHODS We used The Cancer Genome Atlas datasets of pan cancer and liver hepatocellular carcinoma(LIHC)as well as patient cohorts with other cancer types in this study.We investigated genetic alterations of FABPs in various cancer types.mRNA expression was used to determine if FABPs are abnormally expressed in tumor tissues compared to non-tumor controls and to investigate whether their expression correlates with patient clinical outcome,enriched cancer hallmarks and oncogenes previously reported for patients with HCC.We determined the protein levels of FABP5 and its correlated genes in two HCC cell lines and assessed the potential of FABP5 inhibition in treating HCC cells.RESULTS We discovered that a gene cluster including five FABP family members(FABP4,FABP5,FABP8,FABP9 and FABP12)is frequently co-amplified in cancer.Amplification,in fact,is the most common genetic alteration for FABPs,leading to overexpression of FABPs.FABP5 showed the greatest differential mRNA expression comparing tumor with non-tumor tissues.High FABP5 expression correlates well with worse patient outcomes(P<0.05).FABP5 expression highly correlates with enrichment of G2M checkpoint(r=0.33,P=1.1e-10),TP53 signaling pathway(r=0.22,P=1.7e-5)and many genes in the gene sets such as CDK1(r=0.56,P=0),CDK4(r=0.49,P=0),and TP53(r=0.22,P=1.6e-5).Furthermore,FABP5 also correlates well with two co-expressed oncogenes PLK1 and BIRC5 in pan cancer especially in LIHC patients(r=0.58,P=0;r=0.58,P=0;respectively).FABP5high Huh7 cells also expressed higher protein levels of p53,BIRC5,CDK1,CDK2,and CDK4 than FABP5low HepG2 cells.FABP5 inhibition more potently inhibited the tumor cell growth in Huh7 cells than in HepG2 cells.CONCLUSION We discovered that FABP5 gene is frequently amplified in cancer,especially in HCC,leading to its significant elevated expression in HCC.Its high expression correlates well with worse patient outcome,enriched cancer hallmarks and oncogenes in HCC.FABP5 inhibition impaired the cell viability of FABP5high Huh7 cells.All these support that FABP5 is a novel therapeutic target for treating FABP5high HCC.

Changes and significance of serum ubiquitin carboxyl-terminal hydrolase L1 and glial fibrillary acidic protein in patients with glioma

BACKGROUND Brain gliomas are malignant tumors with high postoperative recurrence rates.Early prediction of prognosis using specific indicators is of great significance.AIM To assess changes in ubiquitin carboxy-terminal hydrolase L1(UCH-L1)and glial fibrillary acidic protein(GFAP)levels in patients with glioma pre-and postoperatively.METHODS Between June 2018 and June 2021,91 patients with gliomas who underwent surgery at our hospital were enrolled in the glioma group.Sixty healthy volunteers were included in the control group.Serum UCH-L1 and GFAP levels were measured in peripheral blood collected from patients with glioma before and 3 d after surgery.UCH-L1 and GFAP levels in patients with glioma with different clinicopathological characteristics were compared before and after surgery.The patients were followed-up until February 2022.Postoperative glioma recurrence was recorded to determine the serum UCH-L1 and GFAP levels,which could assist in predicting postoperative glioma recurrence.RESULTS UCH-L1 and GFAP levels in patients with glioma decreased significantly 3 d after surgery compared to those before therapy(P<0.05).However,UCH-L1 and GFAP levels in the glioma group were significantly higher than those in the control group before and after surgery(P<0.05).There were no statistically significant differences in preoperative serum UCH-L1 and GFAP levels among patients with glioma according to sex,age,pathological type,tumor location,or number of lesions(P>0.05).Serum UCH-L1 and GFAP levels were significantly lower in the patients with WHO grade I-II tumors than in those with gradeⅢ-IV tumors(P<0.05).Serum UCH-L1 and GFAP levels were lower in the patients with tumor diameter≤5 cm than in those with diameter>5 cm,in which the differences were statistically significant(P<0.05).Glioma recurred in 22 patients.The preoperative and 3-d postoperative serum UCH-L1 and GFAP levels were significantly higher in the recurrence group than these in the non-recurrence group(P<0.05).Receiver operating characteristic curves were plotted.The areas under the curves of preoperative serum UCH-L1 and GFAP levels for predicting postoperative glioma recurrence were 0.785 and 0.775,respectively.However,the efficacy of serum UCH-L1 and GFAP levels 3 d after surgery in predicting postoperative glioma recurrence was slightly lower compared with their preoperative levels.CONCLUSION UCH-L1 and GFAP efficiently reflected the development and recurrence of gliomas and could be used as potential indicators for the recurrence and prognosis of glioma.

Anti-glial fibrillary acidic protein antibody and anti-aquaporin-4 antibody double-positive neuromyelitis optica spectrum disorder:A case report

BACKGROUND A case of neuromyelitis optica spectrum disorder(NMOSD)with positive cerebrospinal fluid(CSF)anti-aquaporin-4 antibody(AQP4-IgG)and anti-glial fibrillary acidic protein IgG(GFAP-IgG)at the time of relapse was reported.The exact roles of GFAP-IgG in NMOSD are not fully understood and are the subject of ongoing research.This study revealed the possible connection between GFAPIgG and the occurrence or development of diseases.CASE SUMMARY A 19-year-old woman was admitted to the hospital due to a constellation of symptoms,including dizziness,nausea,and vomiting that commenced 1 year prior,reoccurred 2 mo ago,and were accompanied by visual blurring that also began 2 mo ago.Additionally,she presented with slurred speech and ptosis,both of which emerged 1 mo ago.Notably,her symptoms deteriorated 10 d prior to admission,leading to the onset of arm and leg weakness.During hospitalization,magnetic resonance imaging showed high T2-fluid attenuated inversion recovery signals,and slightly high and equal diffusion-weighted imaging signals.The serum antibody of AQP4-IgG tested positive at a dilution of 1:100.CSF antibody testing showed positive results for GFAP-IgG at a dilution of 1:10 and AQP4-IgG at a dilution of 1:32.Based on these findings,the patient was diagnosed with NMOSD.She received intravenous methylprednisolone at a daily dose of 500 mg for 5 d,followed by a tapering-off period.Afterward,the rate of reduction was gradually slowed down and the timely use of immunosuppressants was implemented.CONCLUSION The CFS was slightly GFAP-IgG-positive during the relapse period,which can aid in the diagnosis and treatment of the disease.

Effects of P2Y_1 receptor on glial fibrillary acidic protein and glial cell line-derived neurotrophic factor production of astrocytes under ischemic condition and the related signaling pathways

Objective The present study aimed to explore the role of P2Y1 receptor in glial fibrillary acidic protein （GFAP） production and glial cell line-derived neurotrophic factor （GDNF） secretion of astrocytes under ischemic insult and the related signaling pathways. Methods Using transient right middle cerebral artery occlusion （tMCAO） and oxygen-glucose-serum deprivation for 2 h as the model of ischemic injury in vivo and in vitro, immunofluorescence, quantitative real-time reverse transcription-polymerase chain reaction （RT-PCR）, Western blotting, enzyme linked immunosorbent assay （ELISA） were used to investigate location of P2Y1 receptor and GDNF, the expression of GFAP and GDNF, and the changes of signaling molecules. Results Blockage of P2Y1 receptor with the selective antagonist N^6-methyl-2′-deoxyadenosine 3′,5′-bisphosphate diammonium （MRS2179） reduced GFAP production and increased GDNF production in the antagonist group as compared with simple ischemic group both in vivo and in vitro. Oxygen-glucose-serum deprivation and blockage of P2Y1 receptor caused elevation of phosphorylated Akt and cAMP response element binding protein （CREB）, and reduction of phosphorylated Janus kinase2 （JAK2） and signal transducer and activator of transcription3 （STAT3, Ser727）. After blockage of P2Y1 receptor and deprivation of oxygen-glucose-serum, AG490 （inhibitor of JAK2） reduced phosphorylation of STAT3 （Ser727） as well as expression of GFAP; LY294002, an inhibitor of phosphatidylinositol 3-kinase （PI3-K）, decreased phosphorylation of Akt and CREB; the inhibitor of mitogen-activated protein kinase kinase 1/2 （MEK 1/2） U0126, an important molecule of Ras/extracellular signal- regulated kinase （ERK） signaling pathway, decreased the phosphorylation of JAK2, STAT3 （Ser727）, Akt and CREB. Conclusion These results suggest that P2Y1 receptor plays a role in the production of GFAP and GDNF in astrocytes under transient ischemic condition and the related signaling pathways may be JAK2/STAT3 and PI3-K/Akt/CREB, respectively, and that crosstalk probably exists between them.

Supplementing the early diet of broilers with soy protein concentrate can improve intestinal development and enhance short-chain fatty acid-producing microbes and short-chain fatty acids,especially butyric acid

Background:Research on nutrition in early-life commonly focuses on the maturation of the intestine because the intestinal system is crucial for ensuring continued growth.To explore the importance of early nutrition regulation in animals,soy protein concentrate(SPC)was added to the early diet of broilers to investigate its effects on amino acid digestibility,intestinal development,especially intestinal microorganisms,and broiler metabolites.A total of 192 oneday-old Arbor Acres(AA)male broilers were randomly assigned to two experimental treatments with 8 replicates of 12 birds.The control group was fed a basal diet(control),and the treatment group was fed a basal diet supplemented with 12%SPC(SPC12)during the first 10 d(starter phase).From d 11 to 21(grower phase)and d 22 to 42(finisher phase),a basal diet was fed to both treatment groups.Results:SPC reduced the pH value and acid-binding capacity of the starter diet(P<0.05,d 10);SPC in the early diet enhanced the gizzard weight(P<0.05,d 10 and d 42)and the ileum weight(P<0.05,d 10)and decreased the weight and length of the jejunum(P<0.05,d 10)and the relative length of the duodenum and jejunum(P<0.05,d 10).At the same time,SPC enhanced villus height(P<0.05,d 10)and muscle thickness in the jejunum and ileum(P<0.05,d 10)and increased the number of goblet cells in the duodenum(P<0.05,d 10).Meanwhile,SPC increased the Chao1 index and the ACE index(P<0.05,d 10)and altered the composition of caecal microflora at d 10.SPC also increased the relative abundance of Alistipes,Anaerotruncus,Erysipelatoclostridium,Intestinimonas and Flavonifractor bacteria(P<0.05,d 10).At the same time,the concentrations of caecal butyric acid and total short-chain fatty acids(SCFAs)were also increased in the SPC12 group(P<0.05,d 10).Conclusions:In summary,the results showed that supplementing the starter diet of broilers with SPC has a significant effect on the early development of the intestine and the microflora.

Expressions of nestin and glial fibrillary acidic protein in rat retina after optic nerve transection

AIM：To assess the expression of nestin and glial fibrillary acidic protein（GFAP）in rat retina after optic nerve transection.METHODS：Rats were randomly divided into normal control group,sham group and operation group,and used for establishing an animal model of optic nerve transection.Retinal specimen of each group was collected at 3,48h,7and 14d postoperative.Nestin and GFAP expressions on sagittal sections were analyzed by immunohistochemical staining,and protein extraction was analyzed by Western blot.RESULTS：Immunohistochemical analysis showed that nestin positive staining was rarely detected in normal control group and sham group,while sham group showed weak positive staining at 3h postoperative,the reaction gradually increased at 48h postoperative,and reached its maximum at 7d postoperative,and then decreased at 14d postoperative.Compared to the expression of GFAP,there was not statistically significant obvious difference among three groups（P〉0.05）.Result of Western blot method was consistent with that of immunohistochemical method.CONCLUSION：The expression of nestin increased in a time dependent fashion in Müller cells of retina following optic nerve transection,which was statistically significant,but there was no obvious difference in GFAP expression.The results indicate that an increase in colloid synthesis in retina following optic nerve transection can improve the retinal neurons’environment.

Hippocampal and cortical expression of gamma-aminobutyric acid transporter 1 and glial fibrillary acidic protein in pentylenetetrazol-induced chronic epileptic rats

BACKGROUND： Gamma-aminobutyric acid transporter plays an important role in gamma-aminobutyric acid metabolism, and is highly associated with epilepsy seizures. Pathologically, astrocytes release active substances that alter neuronal excitability, and it has been demonstrated that astrocytes play a role in epileptic seizures. OBJECTIVE： To observe changes in gamma-aminobutyric acid transporter 1 and glial fibrillary acidic protein expression in the hippocampus and cortex of the temporal lobe in rats with pentylenetetrazol-induced chronic epilepsy. DESIGN, TIME AND SETTING： Randomized, controlled, animal experiment was performed at the Department of Neurobiology, Third Military University of Chinese PLA between January 2006 and December 2007. MATERIALS： Pentylenetetrazol was purchased from Sigma, USA; rabbit anti-rat gammaaminobutyric acid transporter 1 and glial fibrillary acidic protein were from Chemicon, USA. METHODS： A total of 40 Sprague Dawley rats were divided into model and control groups. Rat models of chronic epilepsy were created by pentylenetetrazol kindling, and were subdivided into 3-, 7-, and 14-day kindling subgroups. MAIN OUTCOME MEASURES： Gamma-aminobutyric acid transporter 1 and glial fibrillary acidic protein expression, as well as the number of positive cells in the hippocampus and cortex of temporal lobe of rats, were determined by immunohistochemistry and Western blot analyses. RESULTS： Compared with the control group, the number of gamma-aminobutyric acid transporter 1 and glial fibrillary acidic protein -positive cells in the hippocampus and cortex of rats with pentylenetetrazol-induced epilepsy significantly increased, gamma-aminobutyric acid transporter 1 and glial fibrillary acidic protein expression increased after 3 days of kindling, reached a peak on day 7, and remained at elevated levels at day 14 （P〈 0.05）. CONCLUSION： Astrocytic activation and gamma-aminobutyric acid transporter 1 overexpression may contribute to pentylenetetrazol-induced epilepsy.

Scorpion ethanol extract and valproic acid effects on hippocampal glial fibrillary acidic protein expression in a rat model of chronic-kindling epilepsy induced by lithium chloride-pilocarpine

The present study analyzed the effects of ethanol extracts of scorpion on epilepsy prevention and hippocampal expression of glial fibrillary acidic protein in a lithium chloride-pilocarpine epileptic rat model. Results were subsequently compared with valproic acid. Results showed gradually- increased hippocampal glial fibrillary acidic protein expression following model establishment; glial fibrillary acidic protein mRNA expression was significantly increased at 3 days, reached a peak at 7 days, and then gradually decreased thereafter. Ethanol extracts of scorpion doses of 580 and 1 160 mg/kg, as well as 120 mg/kg valproic acid, led to a decreased number of glial fibrillary acidic protein-positive cells and glial fibrillary acidic protein mRNA expression, as well as decreased seizure grades and frequency of spontaneously recurrent seizures. The effects of 1 160 mg/kg ethanol extracts of scorpion were equal to those of 120 mg/kg valproic acid. These results suggested that the anti-epileptic effect of ethanol extracts of scorpion were associated with decreased hippocampal glial fibrillary acidic protein expression in a rat model of lithium chlofide-pilocarpine induced epilepsy.

Effect of electroacupuncture on glial fibrillary acidic protein and nerve growth factor in the hippocampus of rats with hyperlipidemia and middle cerebral artery thrombus

Electroacupuncture(EA)has been shown to reduce blood lipid level and improve cerebral ischemia in rats with hyperlipemia complicated by cerebral ischemia.However,there are few studies on the results and mechanism of the effect of EA in reducing blood lipid level or promoting neural repair after stroke in hyperlipidemic subjects.In this study,EA was applied to a rat model of hyperlipidemia and middle cerebral artery thrombosis and the condition of neurons and astrocytes after hippocampal injury was assessed.Except for the normal group,rats in other groups were fed a high-fat diet throughout the whole experiment.Hyperlipidemia models were established in rats fed a high-fat diet for 6 weeks.Middle cerebral artery thrombus models were induced by pasting 50%FeCl3 filter paper on the left middle cerebral artery for 20 minutes on day 50 as the model group.EA1 group rats received EA at bilateral ST40(Fenglong)for 7 days before the thrombosis.Rats in the EA1 and EA2 groups received EA at GV20(Baihui)and bilateral ST40 for 14 days after model establishment.Neuronal health was assessed by hematoxylin-eosin staining in the brain.Hyperlipidemia was assessed by biochemical methods that measured total cholesterol,triglyceride,low-density lipoprotein and high-density lipoprotein in blood sera.Behavioral analysis was used to confirm the establishment of the model.Immunohistochemical methods were used to detect the expression of glial fibrillary acidic protein and nerve growth factor in the hippocampal CA1 region.The results demonstrated that,compared with the model group,blood lipid levels significantly decreased,glial fibrillary acidic protein immunoreactivity was significantly weakened and nerve growth factor immunoreactivity was significantly enhanced in the EA1 and EA2 groups.The repair effect was superior in the EA1 group than in the EA2 group.These findings confirm that EA can reduce blood lipid,inhibit glial fibrillary acidic protein expression and promote nerve growth factor expression in the hippocampal CA1 region after hyperlipidemia and middle cerebral artery thrombosis.All experimental procedures and protocols were approved by the Animal Use and Management Committee of Beijing University of Chinese Medicine,China(approval No.BUCM-3-2018022802-1002)on April 12,2018.

Aberrant methylation of secreted protein acidic and rich in cysteine gene and its significance in gastric cancer

BACKGROUND Aberrant methylation in DNA regulatory regions could downregulate tumor suppressor genes without changing the sequences.However,our knowledge of secreted protein acidic and rich in cysteine(SPARC)and its aberrant methylation in gastric cancer(GC)is still inadequate.In the present research,we performed fundamental research to clarify the precise function of methylation on SPARC and its significance in GC.AIM To investigate promoter methylation and the effects of the SPARC gene in GC cells and tissues and to evaluate its clinical significance.METHODS Plasmids that overexpressed the SPARC gene were transfected into human GC BGC-823 cells;non-transfected cells were used as a control group(NC group).Quantitative real-time polymerase chain reaction and western blotting(WB)were then used to detect the expression of SPARC.Methylation-specific polymerase chain reaction was executed to analyze the gene promoter methylation status.Cell viability was measured by the cell counting kit-8 assay.The migration and invasion ability of cells were detected by scratch assays and transwell chamber assays,respectively.Cell cycle events and apoptosis were observed with a flow cytometer.RESULTS The expression of SPARC mRNA in GC tissues and cells was significantly lower and showed differing degrees of hypermethylation,respectively,than that in normal adjacent tissues and control cells.Treatment with 5-Aza-2’-deoxycytidine(5-Aza-Cdr)was able to restore the expression of SPARC and reverse promoter hypermethylation.Overexpression of the SPARC gene significantly inhibited proliferation,migration,and invasion of GC cells,while also causing cell cycle arrest and apoptosis;the NC group exhibited the opposite effects.CONCLUSION This study demonstrated that SPARC could function as a tumor suppressor and might be silenced by promoter hypermethylation.Furthermore,in GC cells,SPARC inhibited migration,invasion,and proliferation,caused cell cycle arrest at the G0/G1 phase,and promoted apoptosis.

Glial fibrillary acidic protein levels are associated with global histone H4 acetylation after spinal cord injury in rats

Emerging evidence has suggested global histone H4 acetylation status plays an important role in neural plasticity. For instance, the imbalance of this epigenetic marker has been hypothesized as a key factor for the development and progression of several neurological diseases. Likewise, astrocytic reactivity-a wellknown process that markedly influences the tissue remodeling after a central nervous system injury-is crucial for tissue remodeling after spinal cord injury（SCI）. However, the linkage between the above-mentioned mechanisms after SCI remains poorly understood. We sought to investigate the relation between both glial fibrillary acidic protein（GFAP） and S100 calcium-binding protein B（S100B）（astrocytic reactivity classical markers） and global histone H4 acetylation levels. Sixty-one male Wistar rats（aged ~3 months） were divided into the following groups： sham; 6 hours post-SCI; 24 hours post-SCI; 48 hours post-SCI; 72 hours post-SCI; and 7 days post-SCI. The results suggested that GFAP, but not S100B was associated with global histone H4 acetylation levels. Moreover, global histone H4 acetylation levels exhibited a complex pattern after SCI, encompassing at least three clearly defined phases（first phase： no changes in the 6, 24 and 48 hours post-SCI groups; second phase： increased levels in the 72 hours post-SCI group; and a third phase： return to levels similar to control in the 7 days post-SCI group）. Overall, these findings suggest global H4 acetylation levels exhibit distinct patterns of expression during the first week post-SCI, which may be associated with GFAP levels in the perilesional tissue. Current data encourage studies using H4 acetylation as a possible biomarker for tissue remodeling after spinal cord injury.

Expression of vimentin and glial fibrillary acidic protein in central nervous system development of rats

Objective: To investigate the distribution and contents of vimentin(Vim) and glial fibrillary acidic protein(GFAP) immunoreactivities in the central nervous system(CNS)of normal newborn, adult and aged rats.Methods: In this study, thirty healthy and normal Sprague–Dawley rats were simply classified into three groups: Newborn(7 days aged), adult(5 months aged) and aged(24 months aged) rats. Brains and spinal cord were dissected and cut into frozen sections. The expression of Vim and GFAP in CNS were detected by confocal immunofluorescence.Results: In each group, Vim was expressed in all the regions of CNS including the hippocampal, cerebral cortex, the third ventricle and spinal cord, and the expression was highest in neuron-like cell of newborn rats, while Vim was mainly expressed in cell bodies in adult and aged rats. GFAP was expressed in all the regions of CNS including the hippocampal, cerebral cortex, the third ventricle and spinal cord, and the expression was in astrocytes of aged rats. In the third ventricle, Vim was detected in all groups, and only observed in neuron-like cells of newborn. Meanwhile, the GFAP expression showed no significant differences between adult and aged rats in this region. The co-localization of Vim and GFAP were mainly observed in hippocampus and cerebral cortex of newborn,but this co-localization was found in the third ventricle of the rats in all groups.Conclusion: Our data demonstrate for the first time that the expression of Vim and GFAP in the rat's CNS during development. This data may provide a foundation for the further mechanistic studies of these two main intermediate filaments during development of CNS.

Dynamic changes of glial fibrillary acidic protein and nestin in the hippocampus of adult rat brain following ischemic vascular dementia

Vascular dementia produced by permanent ligation of bilateral common carotid arteries involves progressive deterioration of intellectual and cognitive function in rats, which are closely associated with the hippocampus. This study used immunohistochemical analysis to detect the expression of glial fibrillary acidic protein and nestin in the hippocampus in a vascular dementia model. The results revealed that both glial fibrillary acidic protein and nestin expression were increased 1 day after permanent ligation of the bilateral common carotid arteries, compared with a sham-operated group. The expression of glial fibrillary acidic protein peaked at 7 days post-surgery. The expression of nestin was a little weaker than that of glial fibrillary acidic protein, and peaked at 14 days （P 〈 0.01）. The expression of both proteins slightly decreased at 21 and 28 days, accompanied by recovery of cerebral blood flow. In conclusion, this study demonstrated that glial fibrillary acidic protein and nestin exhibited dynamic expression in the rat hippocampus after permanent ligation of bilateral common carotid arteries. This finding suggests that dynamic alterations in protein expression play an important role in the pathogenesis of vascular dementia.

Optic neuropathy and increased retinal glial fibrillary acidic protein due to microbead-induced ocular hypertension in the rabbit

AIM： To characterize whether a glaucoma model with chronic elevation of the intraocular pressure （IOP） was able to be induced by anterior chamber injection of microbeads in rabbits.METHODS： In order to screen the optimal dose of microbead injection, IOP was measured every 3d for 4wk using handheld applanation tonometer after a single intracameral injection of 10 μL, 25 μL, 50 μL or 100 μL microbeads （5×10^6 beads/mL; n=6/group） in New Zealand White rabbits. To prolong IOP elevation, two intracameral injections of 50 μL microbeads or phosphate buffer saline （PBS） were made respectively at days 0 and 21 （n=24/group）. The fellow eye was not treated. At 5wk after the second injection of microbeads or PBS, bright-field microscopy and transmission electron microscopy （TEM） were used to assess the changes in the retina. The expression of glial fibrillary acidic protein （GFAP） in the retina was evaluated by immunofluorescence, quantitative real-time polymerase chain reaction and Western blot at 5wk after the second injection of microbeads.RESULTS： Following a single intracameral injection of 10 μL, 25 μL, 50 μL or 100 μL microbead, IOP levels showed a gradual increase and a later decrease over a 4wk period after a single injection of microbead into the anterior chamber of rabbits. A peak IOP was observed at day 15 after injection. No significant difference in peak value of IOP was found between 10 μL and 25 μL groups （17.13±1.25 mm Hg vs 17.63±0.74 mm Hg; P=0.346）. The peak value of IOP from 50 μL group （23.25±1.16 mm Hg） was significantly higher than 10 μL and 25 μL groups （all P〈0.05）. Administration of 100 μL microbead solution （23.00±0.93 mm Hg） did not lead to a significant increase in IOP compared to the 50 μL group （P=0.64）. A prolonged elevated IOP duration up to 8wk was achieved by administering two injections of 50 μL microbeads （20.48±1.21 mm Hg vs 13.60±0.90 mm Hg in PBS-injected group; P〈0.05）. The bright-field and TEM were used to assess the changes of retinal ganglion cells （RGCs）. Compared with PBS-injected group, the extended IOP elevation was associated with the degeneration of optic nerve, the reduction of RGC axons （47.16%, P〈0.05） and the increased GFAP expression in the retina （4.74±1.10 vs 1.00±0.46, P〈0.05）.CONCLUSION： Two injections of microbeads into the ocular anterior chamber of rabbits lead to a prolonged IOP elevation which results in structural abnormality as well as loss in RGCs and their axons without observable ocular structural damage or inflammatory response. We have therefore established a novel and practical model of experimental glaucoma in rabbits.

Determination of inter- and intra-subtype/species varia-tions in polymerase acidic protein from influenza A virus using amino-acid pair predictability

The polymerase acidic protein is an important family of proteins from influenza A virus, which is classified as many different subtypes or spe-cies. Thus, an important question is if these classifications are numerically distinguishable with respect to the polymerase acidic protein. The amino-acid pair predictability was used to transfer 2432 polymerase acidic proteins into 2432 scalar data. The one-way ANOVA found these polymerase acidic proteins distinguish-able in terms of subtypes and species. However, the large residuals in ANOVA suggested a pos-sible large intra-subtype/species variation. Therefore, the inter- and intra-subtype/species variations were studied using the model II ANOVA. The results showed that the in-tra-subtype/species variations accounted most of variation, which was 100% in total for both inter- and intra- subtype/species variations. Our analysis threw lights on the issue of how to de-termine a wide variety of patterns of antigenic variation across space and time, and within and between subtypes as well as hosts.

Curcumin alters expression of glial fibrillary acidic protein and nestin following chronic cerebral ischemia

Astrocytes can alter their appearance and become reactive following chronic cerebral ischemia. In the present study, a rat model of chronic cerebral ischemia was treated with 50 and 100 mg/kg curcumin. Results showed that pathological changes of neuronal injury in hippocampal CA1 area of rats induced by chronic cerebral ischemia were attenuated, as well as upregulated expression of glial fibriliary acidic protein and nestin, in a dose-dependent manner.

Assessment of Neurotoxicity: Use of Glial Fibrillary Acidic Protein as a Biomarker

Diverse neurotoxic insults result in proliferation and hypertrophy of astrocytes. The hallmark of this response is enhanced expression of the major intermediate filament protein of astrocytes, glial fibrillary acidic protein (GFAP). These observations suggest that GFAP may be a useful biomarker of neurotoxicity. To investigate this possibility, we administered prototype neurotoxicants to experimental animals and assessed the effects of these agents on the tissue content of GFAP, as determined by radioimmunoassay. A review of the background, design, and results of these experiments are presented in this paper. Our findings indicate that GFAP is a sensitive and specific biomarker of neurotoxicity.