The inhibitory effects of class I histone deacetylases on hippocampal neuroinflammatory regulation in aging mice with postoperative cognitive dysfunction.

OBJECTIVE: Neuroinflammation in the hippocampus has been determined to contribute to postoperative cognitive dysfunction (POCD) occurrence in elderly individuals. Histone deacetylases (HDACs) have been identified as important regulators of inflammation. However, the roles of different types of HDACs in POCD have never been fully explored. MATERIALS AND METHODS: POCD mouse models were established using isoflurane and validated by the Morris water maze test. The mice were pretreated with UF010 [a Class I HDAC inhibitor (HDACi)], MC1568 (a Class II HDACi) and SAHA (a Class I and II HDACi) before POCD establishment. HDAC protein levels and the activity of the NF-κB/p65, JAK/STAT and TLR/MyD88 signaling pathways in the hippocampus were investigated by Western blot (WB). The enrichment of HDACs on the promoters of genes was detected using ChIP-qPCR. RESULTS: Class I HDACs, including HDAC2 and HDAC8, and Class II HDACs, including HDAC4, HDAC7 and HDAC10, were all upregulated in the POCD group compared to the control group. Furthermore, compared to the MC1568 pretreatment group and the control group, the groups pretreated with UF010 and SAHA exhibited amelioration of the effects of anesthesia/surgery induced POCD and compromised inflammatory reactions in the hippocampus. Likewise, the NF-κB/p65, JAK/STAT and TLR/MyD88 signaling pathways were inactivated upon pretreatment with UF010 and SAHA compared to MC1568. Finally, the transcription of the genes negatively regulating these three pathways declined, and the enrichment of HDAC1, HDAC2 and HDAC8 was significantly elevated in the context of POCD. CONCLUSIONS: Class I HDACs, especially HDAC1, HDAC2 and HDAC8, play crucial roles in enhancing neuroinflammation in the hippocampus and causing POCD. Class I HDACs are potential therapeutic targets for POCD prevention and treatment via neuroinflammation inhibition.

LncRNA ST8SIA6-AS1 promotes colorectal cancer cell proliferation, migration and invasion by regulating the miR-5195/PCBP2 axis.

OBJECTIVE: Long non-coding RNAs (lncRNAs) have been reported to play a vital role in the development and progression of various cancers, including colorectal cancer (CRC). Although the dysregulation of lncRNA ST8SIA6-AS1 participates in the development of multiple malignancies, the underlying molecular mechanisms of ST8SIA6-AS1 in regulating CRC progression remain to be fully discovered. PATIENTS AND METHODS: The expression level of lncRNA ST8SIA6-AS1 was examined in the tumor tissues and paracancerous tissues of CRC patients. Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was utilized to examine the expression levels of ST8SIA6-AS1, miR-5195, and Poly-(C) Binding Protein 2 (PCBP2). The protein expression level of PCBP2 was detected by Western blotting. MTT assay was performed to measure the proliferation of HCT-116 and SW480 cells. Cell migration and invasion abilities were measured by transwell assay. Luciferase reporter assay was used to examine the interaction between miR-5195 and ST8SIA6-AS1 or PCBP2. RESULTS: This study revealed that lncRNA ST8SIA6-AS1 was upregulated in CRC tissues and cells. Knockdown of ST8SIA6-AS1 inhibited proliferation, migration, and invasion of CRC cells. Moreover, ST8SIA6-AS1 was proved to inhibit miR-5195 expression by directly targeting miR-5195. In addition, it was demonstrated that overexpression of miR-5195 inhibited CRC progression. Furthermore, PCBP2 was shown to enhance sh-ST8SIA6-AS1 and miR-5195 mimics-attenuated cell proliferation, migration, and invasion by directly binding to miR-5195. CONCLUSIONS: Our study revealed that ST8SIA6-AS1 promoted CRC progression via the miR-5195/PCBP2 axis. This study may provide an improved understanding of the pathogenesis of CRC.

Isolation, identification and characterization of lignin-degrading bacteria from Qinling, China.

AIMS: Lignin is an aromatic heteropolymer forming a physical barrier and it is a big challenge in biomass utilization. This paper first investigated lignin-degradation bacteria from rotten wood in Qinling Mountain. METHODS AND RESULTS: Nineteen potential strains were selected and ligninolytic enzyme activities were determined over 84 h. Strains that had higher enzyme activities were selected. Further, the biodegradation of wheat straw lignin and alkali lignin was evaluated indicating that Burkholderia sp. H1 had the highest capability. It was confirmed by gel permeation chromatography and field emission scanning electron microscope that alkali lignin was depolymerized into small fragments. The degraded products were analysed using gas chromatography-mass spectrometry. The total ion chromatograph of products treated for 7 days showed the formation of aromatic compounds, an important intermediate from lignin degradation. Interestingly, they disappeared in 15 days while the aldehyde and ester compounds increased. CONCLUSIONS: The results suggest that the lignin-degrading bacteria are abundant in rotten wood and strain H1 has high potential to break down lignin. SIGNIFICANCE AND IMPACT OF THE STUDY: The diversity of lignin-degrading bacteria in Qinling Mountain is revealed. The study of Burkholderia sp. H1 expands the range of bacteria for lignin degradation and provides novel bacteria for application to lignocellulosic biomass.

Methods of RNA preparation affect mRNA abundance quantification of reference genes in pig maturing oocytes.

To ensure accurate normalization and quantification of target RNA transcripts using reverse transcription quantitative polymerase chain reaction (RT-qPCR), most studies focus on the identification of stably expressed gene(s) as internal reference. However, RNA preparation methods could also be an important factor, especially for test samples of limited quantity (e.g. oocytes). In this study, we aimed to select appropriate reference gene(s), and evaluate the effect of RNA preparation methods on gene expression quantification in porcine oocytes and cumulus cells during in vitro maturation. Expression profiles of seven genes (GAPDH, 18S, YWHAG, BACT, RPL4, HPRT1 and PPIA) were examined, on RNA samples extracted from cumulus cells (RNeasy Kit) and oocytes (RNeasy Kit and Lysis Kit) during in vitro maturation, respectively. Interestingly, different RNA preparation methods were found to potentially affect the quantification of reference gene expression in pig oocytes cultured in vitro. After geNorm analyses, the most suitable genes for normalization were identified, GAPDH/18S for cumulus cells and YWHAG/BACT for oocytes, respectively. Thus, our results provide useful data and information on the selection of better reference genes and RNA preparation method for related functional studies.

Dexmedetomidine protects against cisplatin-induced acute kidney injury in mice through regulating apoptosis and inflammation.

OBJECTIVE AND DESIGN: Cisplatin-based chemotherapy has been widely used in the perioperative period of cancer surgery, which exacerbates the risk of renal injury. In this study, we examined whether dexmedetomidine (DEX), a commonly used anesthetic adjuvant, shows a protective effect against cisplatin-induced acute kidney injury. MATERIALS: Acute kidney injury in mice was induced by cisplatin. TREATMENTS: Mice were administered with DEX 25 µg/kg or atipamezole 250 µg/kg (once a day, for 3 days) after cisplatin treatment. METHODS: The renal function and tubular damage score were evaluated at 72 h following cisplatin administration. Apoptotic tubular cells were detected by TUNEL assay. Caspase-3, p53, Bax, F4/80+ macrophages, CD3+ T cells, and NF-κB were examined by immunohistochemistry staining or Western blot. Tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, and monocyte chemoattractant protein (MCP)-1 in kidney were measured using real-time polymerase chain reaction. RESULTS: DEX treatment preserved renal function and reduced tubular damage score of mice after cisplatin administration. Mice treated with DEX exhibited less apoptotic tubular cells in response to cisplatin insult, which was associated with decreased Bax and reduced activation of p53 and caspase-3. DEX suppressed the infiltration of macrophages and T cells into the kidneys following cisplatin treatment, which was involved in the inhibition of NF-κB activation and decreased expression of TNF-α, IL-1ß, IL-6, and MCP-1. Furthermore, we showed that the renoprotective effect conferred by DEX may be related to α2 adrenoceptor-dependent pathway. CONCLUSION: We demonstrate that DEX protects the kidney against cisplatin-induced AKI by the regulation of apoptosis and inflammatory response.

Effects of polymorphisms of serotonin transporter promoter (5-HTTLPR) and brain derived neurotrophic factor gene (G196A rs6265) on the risk of major depressive disorder in the Chinese Han population.

OBJECTIVE: The etiology of Major depressive disorder (MDD) is multifactorial but the genetic risk is an important factor. Previous studies have shown a significant interaction between serotonin and brain-derived neurotrophic factor (BDNF) in brain function. The serotonin transporter protein promoter polymorphism (5-HTTLPR) and BDNF (rs6265) are two of the most studied candidate gene polymorphisms in relation to MDD. However, the effect of 5-HTTLPR-BDNF (rs6265) interaction on MDD-risk is not consistent. PATIENTS AND METHODS: This study recruited 459 patients with MDD and 412 healthy volunteers in a Chinese Han population. Polymerase chain reaction (PCR)-based genotyping was used to detect polymorphisms. Logistic regression was applied to estimate the effect of polymorphisms of 5-HTTLPR, BDNF (rs6265), and their interaction. RESULTS: We observed a significant correlation between the heterozygous genotype of 5-HTTLPR and MDD [odds ratio (OR) = 1.42, 95% CI: 1.05~1.91; p = 0.02]. The BDNF (rs6265) polymorphism showed that there is no correlation with MDD. When interaction with BDNF was modeled, for individuals with BDNF (rs6265), genotype GG, cases in the heterozygous group had even higher odds of MDD than those in the combined homozygous group of 5-HTTLPR polymorphism (OR = 2.92, 95% CI: 1.43-5.95; p = 0.003). CONCLUSIONS: Our results suggested that 5-HTTLPR, may be associated with the susceptibility of MDD in an overdominant mode, and there may be a significant interaction between 5-HTTLPR and BDNF (rs6265) polymorphisms in relation to MDD.

Interaction relationships of osteoarthritis and rheumatoid arthritis related genes.

BACKGROUND: Osteoarthritis (OA), also referred to as degenerative joint disease or wear-and-tear arthritis, is caused by the breakdown of joint cartilage. Rheumatoid arthritis (RA) is a chronic, inflammatory type of arthritis. RA is also classified as a kind of autoimmune disease. AIM: To find the important genes in RA and OA. MATERIALS AND METHODS: Comprehensively compared 3 datasets of RA with 2 datasets of OA, 98 genes were sifted. We explored protein-protein associations processed for the 98 genes by mining famous gene/protein interaction/association database. RESULTS: We found most of those genes appear to play a key role in the anti-inflammatory and immunosuppressive effects. CONCLUSIONS: Our research would play a useful role in the diagnosis and treatment of OA and RA.

Toll-like receptor 4 genetic variants and prognosis of breast cancer.

Despite the knowledge of many genetic alterations present in breast cancer, the complexity of this disease precludes placing its biology into a simple conceptual framework. Toll-like receptor 4 (TLR4) plays important roles in regulating innate immunity and may affect the development of cancers. Polymorphisms in TLR4 gene have been shown to be associated with impaired immune responses. Here, we investigated the association of TLR4 polymorphisms with breast cancer. Four functional TLR4 polymorphisms (-2242T/C, Asp299Gly, Thr399Ile, and +3725G/C) were genotyped in a total of 665 breast cancer patients and 768 healthy controls. Data were analyzed using the chi-squared test. Results showed that the prevalence of TLR4 +3725GC and CC genotypes were significantly increased in breast cancer cases when compared with controls [odds ratio (OR) = 1.37, 95% confidence interval (CI) = 1.08-1.73, P = 0.008 and OR = 2.34, 95% CI = 1.66-3.35, P < 0.0001, respectively]. Also, the frequency of TLR4 +3725C allele was significantly higher in breast cancer patients (P < 0.0001). The -2242T/C polymorphism did not show any significant differences between cases and controls. In addition, when analyzing the survival time of breast cancer patients with TLR4 +3725G/C polymorphism, cases with +3725C allele had significantly shorter survival time overall (P = 0.006). These results suggested that polymorphism in TLR4 gene was associated with increased susceptibility to breast cancer and could be used as a prognostic marker for this malignancy.

Sodium valproate inhibits MDA-MB-231 breast cancer cell migration by upregulating NM23H1 expression.

Breast cancer is a common cancer in women, with a highly variable course, from inoffensive to lethal. To find a more effective strategy for its treatment, sodium valproate has been tested as an anti-cancer drug; it is the only clinically available histone deacetylase inhibitor. However, data about the effects of sodium valproate on breast cancer are insufficient in both animals and humans; studies have yielded conflicting conclusions. In particular, little is known about the association between expression of the metastasis suppressor Nm23H1 gene and breast cancer. We hypothesized that sodium valproate regulates NM23H1 expression, and affects migration and/or invasion. We found that sodium valproate at concentrations of 0.8-3.2 mM inhibits migration and modulates Nm23H1 gene expression in a concentration-dependent manner. Confluent MDA-MB-231 cells were scratched by a micropipette tip after VPA treatment for 24 h; 24 h later, the scratch was almostly closed in the 0 mM VPA-treated cells, while the 3.2 mM VPA-treated cells migrated the slowest. The cell migration ratio exposed to 0.8, 1.6 and 3.2 mM VPA was about 66.67, 30.67 and 26.67% (P < 0.05). We also found evidence that sodium valproate upregulates NM23H1 expression, which is a clue to its anti-cancer mode of action. The NM23H1 gene expression was relative fold increased determined by Western blotting at 3.2 mM VPA. Collectively, these observations indicate that sodium valproate has potential for use in breast cancer treatment.

The effect of acetylcholine on pain-related electric activities in the hippocampal CA3 of rats.

Acetylcholine (ACh) regulates pain perception in the central nervous system. However, the mechanism of action of ACh on pain-related neurons in the hippocampal CA3 is not clear. The present study aimed to determine the effect of ACh, muscarinic ACh receptors (mAChRs) agonist pilocarpine and mAChRs antagonist atropine on the pain-evoked responses of pain-excited neuron (PEN) and pain-inhibited neuron (PIN) in the hippocampal CA3 of normal rats. The trains of electric impulses applied to the sciatic nerve were used as noxious stimulation. The electric activities of PEN or PIN in the hippocampal CA3 were recorded by using a glass microelectrode. Our results showed that, in the hippocampal CA3, the intra-CA3 microinjection of ACh (2 µg/1 µl) or pilocarpine (2 µg/1 µl) decreased the discharge frequency and prolonged firing latency of PEN, and increased the discharge frequency and shortened firing inhibitory duration (ID) of PIN, i.e. exhibiting the analgesic effect of ACh or pilocarpine. The intra-CA3 administration of atropine (0.5 µg/1 µl) produced an opposite effect. On the basis of the above-mentioned findings, we can deduce that ACh and mAChRs in the hippocampal CA3 are involved in the modulation of nociceptive response by regulating the electric activities of PEN and PIN.

Lipid peroxidation levels, total oxidant status and superoxide dismutase in serum, saliva and gingival crevicular fluid in chronic periodontitis patients before and after periodontal therapy.

BACKGROUND: Recent data have demonstrated increased lipid peroxidation (LPO) levels and oxidative stress in periodontitis. Malondialdehyde (MDA) and superoxide dismutase (SOD) are both increased during oxidative stress. Furthermore, this study examined SOD concentration, total oxidative status (TOS) and MDA levels in periodontal patients and investigated the longitudinal effect of periodontal therapy on the index levels of chronic periodontitis (CP) patients. METHODS: Serum, saliva and gingival crevicular fluid (GCF) samples were obtained from 48 CP patients and 35 healthy control subjects prior to, as well as after 16 weeks following non-surgical post-periodontal therapy. MDA, TOS and SOD and clinical parameters were determined pre- and post-therapy. RESULTS: The levels of TOS and SOD values were significantly higher in the CP group than in the control group (p < 0.05), but only MDA in GCF. Post-periodontal therapy, serum, saliva and GCF TOS and SOD levels significantly decreased compared to basal levels (p < 0.05), but only MDA in GCF. CONCLUSIONS: LPO was higher in the periodontal region, with TOS and SOD increasing both locally and peripherally. Non-surgical therapy can restore and control the subject antioxidant capacity by locally and systemically modifying the levels of MDA, TOS and SOD.

The effect of dopamine on pain-related neurons in the parafascicular nucleus of rats.

Dopamine (DA) regulates pain perception in the central nervous system (CNS). However, the mechanism of the action of DA in pain-related neurons of the parafascicular nucleus (Pf) is not clear. The present study aimed to determine the effect of DA and its receptor antagonist, droperidol on the pain-evoked responses of the pain-excited neurons (PEN) and pain-inhibited neurons (PIN) in the Pf of rats and to analyze the mechanisms underlying this effect. The trains of electric impulses applied to the sciatic nerve were used as noxious stimulation. The discharges of PEN and PIN in the Pf were recorded by using a glass microelectrode. The results showed that, in the Pf, intra-Pf microinjection of DA (5 microg/0.5 microl) increased the frequency of noxious stimulation-induced discharges of the PEN and decreased the frequency of those of the PIN, while the intra-Pf administration of droperidol (0.15 microg/0.5 microl) produced an opposite effect. On the basis of the above-mentioned findings, we could conclude that DA and its receptors in the Pf are involved in the modulation of the nociceptive response by regulating the discharges of PEN and PIN.

Neuroprotective effect of grafting GDNF gene-modified neural stem cells on cerebral ischemia in rats.

Previous studies indicated the beneficial effects of glial cell line-derived neurotrophic factor (GDNF) and transplanted neural stem cells (NSCs) on stroke. Here, we explored whether transplantation of neural stem cells (NSCs) modified by GDNF gene provides a better therapeutic effect than native NSCs after stroke. Primary rat NSCs were transfected with GDNF plasmid (GDNF/NSCs, labeled by green fluorescent protein from AdEasy-1, GFP). Adult rats were subjected to two-hour middle cerebral artery occlusion and reperfusion, followed by infusion of NSCs (labeled with5-bromo-2'-deoxyuridine before infusion, BrdU), GDNF/NSCs and saline at 3 days after reperfusion (NSCs group, GDNF/NSCs group, control group), respectively. All rats were sacrificed at 1, 2, 3, 5, and 7 weeks after reperfusion. Modified Neurological Severity Scores (mNSS) test and H and E staining were respectively performed to evaluate neurological function and lesion volume. Immunohistochemistry was used to identify implanted cells and observe the expressions of Synaptophysin (Syp) and postsynaptic density-95 (PSD-95) and caspase-3. TdT-mediated dUTP-biotin nick-end labeling (TUNEL) was employed to observe apoptotic cells. Western blotting was used to detect brain-derived neurotrophic factor (BDNF) and NT-3 protein expression. Significant recovery of mNSS was found in GDNF/NSCs rats at 2 and 3 weeks after reperfusion compared with NSCs rats. Lesion volume in the NSCs and GDNF/NSCs groups was reduced significantly compared with control group. The number of NSCs in the GDNF/NSCs group was significantly increased in comparison with NSCs group. Moreover, Syp-immunoreactive product at 2 and 3 weeks after reperfusion and PSD-95 immunoreactive product in the GDNF/NSCs group were significantly increased compared with NSCs group. In contrast, caspase-3 positive cells and TUNEL-positive cells in the GDNF/NSCs group were significantly decreased compared with NSCs group. Significant increase of BDNF protein in the GDNF/NSCs and NSCs groups was observed compared to the control group at different time points of reperfusion, and GDNF/NSCs grafting significantly increased BDNF protein expression compared to NSCs grafting. In addition, significant increase of NT-3 protein in GDNF/NSCs and NSCs groups was detected only at 1 week of reperfusion compared to control group. The results demonstrate that grafting NSCs modified by GDNF gene provides better neuroprotection for stroke than NSCs grafting alone.

Neuroprotective effects of ginsenoside Rb1 on transient cerebral ischemia in rats.

Previous experiments showed that ginsenoside Rb1 (GRb1) reduced infarct and neuronal deficit in rats followed by transient cerebral ischemia. The mechanism of this neuroprotective function is unclear. Here, we tested whether the effect of GRb1 can be achieved through preventing ischemic neuronal death, modulating apoptotic-related genes and affecting glial-derived neurotrophic factor (GDNF) expression in rats subjected to occlusion of the middle cerebral artery. When GRb1(40 mg/kg, i.p.) was administered immediately after reperfusion, the apoptotic cells in the GRb1 group were decreased significantly from 12 to 72 h of reperfusion compared to the ischemia group by TdT-mediated dUTP-biotin nick-end labeling. Immunostaining and Western blotting analysis showed that the expression of GDNF from 3 to 120 h of the GRb1 group was significantly increased compared to the ischemia group, and GDNF expression peaked at 48 h after reperfusion. The enhanced GDNF mRNA in the GRb1 group was not detected by RT-PCR and in situ hybridization compared to the ischemia group, but GDNF mRNA at 48 h after reperfusion was strongly increased in both the ischemia and GRb1 group when compared to other time points. The number of bcl-2-positive cells was significantly increased from 12 to 120 h of reperfusion compared to the ischemia group. However, the number of bax-positive cells in the GRb1 group was significantly declined compared to the ischemia group. In the GRb1 group, the number of neuronal apoptosis inhibitory protein-positive cells from 12 to 120 h after reperfusion was evidently higher than that in the ischemia group. Therefore, ginsenoside Rb1 prevents ischemic neuronal death induced by transient cerebral ischemia, and this mechanism of which is related to increase the expression of the antiapoptotic genes and modulate the expression of GDNF.

Mechanisms of modulation of pregnanolone on glycinergic response in cultured spinal dorsal horn neurons of rat.

The glycine receptors and neurosteroids in spinal cord are both implicated in nociceptive signal processing. However, the modulatory effects of neurosteroid pregnanolone (5beta-pregnan-3alpha-ol-20-one) on native glycine receptors remain unclear. In the present study, we examined the effects of pregnanolone and its three isomers on glycine receptors by using whole-cell patch-clamp technique. Our results showed that pregnanolone reversibly inhibited the amplitude of glycine-induced current mediated by native glycine receptors and recombinant alpha1-, alpha2-, alpha3- and alpha1beta-glycine receptors. In cultured spinal dorsal horn neurons of rats, pregnanolone inhibited the glycine-induced current in dose-dependent manner, with an antagonist concentration inducing half-maximal response of 1.0+/-0.3 microM. The inhibitory effect of pregnanolone on glycine-induced current was voltage-independent and pregnanolone shifted the concentration-response curve for glycine-induced current rightward in a parallel manner without altering the maximal value and Hill coefficient. The isomer of pregnanolone, allopregnanolone (5alpha-pregnan-3alpha-ol-20-one) slightly enhanced glycine-induced current, whereas iso-pregnanolone (5beta-pregnan-3beta-ol-20-one) and iso-allopregnanolone (5alpha-pregnan-3beta-ol-20-one) did not affect the glycine-induced current significantly in cultured spinal dorsal horn neurons. Thus, our results suggest that the inhibitory effect of pregnanolone on glycine-induced current is of a competitive type and depends on the stereo structure of pregnanolone. Furthermore, pregnanolone decreased the amplitude and frequency of the glycinergic miniature inhibitory postsynaptic currents. Through modulating the glycinergic inhibitory neurotransmission, pregnanolone may affect the nociceptive sensory processing under physiological and pathological conditions.

Fish consumption and colorectal cancer: a case-reference study in Japan.

Several clinical studies have suggested that supplementation with fish oils can suppress the proliferation of colorectal mucosa and therefore inhibit the development of colorectal cancer. However, epidemiological evidence concerning fish consumption and risk is inconsistent and limited. To clarify the association between intake of fish and the likelihood of developing colorectal cancer, we conducted a large sample size case-reference study with 928 cases of colon cancer, 622 of rectal cancer and 46886 cancer-free outpatient references aged 40-79 years. The data showed frequent raw/cooked fish intake to be associated with decreased odds ratio (OR) 0.68 with 95% confidence interval (CI) 0.47-0.99 for male colon cancer, especially for males aged over 60 years, smokers and frequent meat eaters. A marginal decrease in the OR (OR 0.58, 95% CI 0.31-1.07) was also detected for female rectal cancer, especially in the regular physical exercise subgroup. However, frequent dried/salted fish intake was found to be associated with increased OR in females younger than 60 years old and alcohol drinkers. Although there is some possible bias in epidemiological studies, the results suggest that frequent raw/cooked fish intake may decrease the risk while dried/salted fish, in contrast, may exert a detrimental effect.