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Abstract: Apple grain aphid, Rhopalosiphum padi (Linnaeus), is an important wheat pest. In China, it has been reported that R. padi has developed high resistance to carbamate and organophosphate insecticides. [...]

Chemosensory systems are considered to play an important role in host plant selection in herbivorous insects. However, few studies have focused on chemosensory proteins (CSPs) for aphid host‐location mechanisms. The roles of CSPs in searching for different Poaceae species (wheat, barley, triticale, maize and sorghum) were tested in Rhopalosiphum padi, an important cereal pest. The olfactometer assays showed that R. padi responds to plant odors. Seven R. padi CSP genes were identified. Influence of aphid morph, tissue and starvation state on expression patterns of CSPs was evaluated. Expression levels of CSP1, CSP4, CSP5 and CSP6 in winged aphids were significantly higher than those in wingless ones. Transcription levels of four genes (CSP1, CSP4, CSP5 and CSP6) were relatively higher in the head with antennae, and the four genes tended to be upregulated following starvation. Silencing of three CSPs (CSP4, CSP5 and CSP6) altered aphid host‐location behavior in response to the five different host plants tested. Three volatile compounds of host plants (octanal, [E]‐2‐hexenol and linalool) have significant attraction to winged R. padi according to the four‐arm olfactometer tests. Molecular docking predicted hydrogen bonding sites which played key roles in the binding of CSP4, CSP5 and CSP6 with volatile compounds. Knockdown of CSP4 or CSP5 significantly decreased the staying time of R. padi in the arms with octanal. However, knockdown of CSP6 could not affect the response of R. padi to octanal. These results bring evidence for the involvement of three CSPs in R. padi host‐location behavior. [ABSTRACT FROM AUTHOR]

Background: Saponins from Rhizoma Panacis Majoris (SRPM) are confirmed to have cardioprotective effect against myocardial ischemia injury by reducing oxidative stress, while its underlying mechanism has not been elucidated until recently. Objective: The objective of this study was to investigate the SRPM's cardioprotection and elucidate its underlying mechanisms. Materials and Methods: Adult male rats were received SRPM treatment in the presence or the absence of the silent information regulator 1 (Sirt1) inhibitor Ex-527 or nuclear factor erythroid 2-related factor 2 (Nrf2) inhibitor ATRA for 14 days and subjected to myocardial ischemia for 0.5 h and then 2 h reperfusion. Cardiac function, infarct size, antioxidant enzyme activities, ROS level and the related mRNA and protein expressions of antiapoptosis protein Bcl-2, proapoptosis protein Bax, caspase-3, caspase-9, Sirt1 and Nrf2-relatived signaling pathways were assessed. Results: SRPM was confirmed to have cardioprotective effects by ameliorating cardiac function, decreasing infarct size, reducing serum creatine kinase (CK), creatine kinase isoenzyme, lactate dehydrogenase and ROS releases and malondialdehyde level, raising total antioxidant capacity, superoxide dismutase, glutathione peroxidase, catalase activities, upregulating myocardial Sirt1, Nrf2, Bcl-2 protein and manganese superoxide dismutase, heme oxygenase-1, NAD(P)H-quinone oxidoreductase 1 and γ-glutamylcysteine synthetase mRNA expressions and downregulating acetylated forkhead box O 1, acetylated peroxisome proliferator-activated receptor γ coactivator 1α, Bax, cleaved caspase-3 and cleaved caspase-9 protein expressions; histopathological observations provided supportive evidence for the aforementioned results. Interestedly, its protective effects were significantly blocked for its combination with Ex-527 or ATRA. Conclusion: The studies demonstrated that SRPM exerted beneficially protective effects on myocardial ischemia/reperfusion injury. It was possibly related to reducing oxidative stress damage by activations of Sirt1 and Nrf2-related antioxidant signaling pathways. Abbreviations used: Ac-FoxO1: Acetylated FoxO1, Ac-Pgc-1α: Acetylated Pgc-1α, ARE: Antioxidant-response element, CK: Creatine kinase, CK-MB: Creatine kinase isoenzyme, DEPPD: N, N-diethyl-paraphenylendiamine, ELSD: Evaporative light scattering detection, FoxO: Forkhead box O, GCLC: Glutamate-cysteine ligase catalytic subunit, GSH-Px: Glutathione peroxidase, HO-1: Heme oxygenase-1, H2O2: Hydrogen peroxide, Keap-1: Kelch-like ECH-associated protein 1, HPLC: High-performance liquid chromatography, LDH: Lactate dehydrogenase, MDA: Malondialdehyde, NAD+: Nicotinamide adenine dinucleotide, MnSOD: Manganese superoxide dismutase, NF-κB: Nuclear factor-kappa B, NQO1: Nicotinamide quinone oxidoreductase 1, NAD(P) H: NAD(P)H-quinone oxidoreductase 1, Nrf2: Nuclear factor erythroid 2-related factor 2, Pgc-1α: Peroxisome proliferator-activated receptor γ coactivator 1α, Sirt1: Silent information regulator 1, SOD: Superoxide dismutase, SRPM: Saponins from Rhizoma Panacis Majoris, I/R: Ischemia/reperfusion, T-AOC: Total antioxidant capacity, TTC: 2,3,5-triphenyltetrazolium chloride. [ABSTRACT FROM AUTHOR]

This study investigated the effects and mechanisms of total saponins of Panax japonicus(TSPJ) against liver injury induced by acetaminophen(APAP). Male Kunming mice were randomly divided into a blank control group, TSPJ group(200 mg·kg~(-1), ig), model group, APAP+ TSPJ low-dose group(50 mg·kg~(-1), ig), APAP+ TSPJ medium-dose group(100 mg·kg~(-1), ig), APAP+ TSPJ high-dose group(200 mg·kg~(-1), ig), and APAP+ N-acetyl-L-cysteine group(200 mg·kg~(-1), ip). The administration group received the corresponding medications via ig or ip once a day for 14 consecutive days. After the last administration for one hour, except for the blank control group and TSPJ group, all groups of mice were given 500 mg·kg~(-1) APAP by gavage. After 24 hours, mouse serum and liver tissue were collected for serum alanine aminotransferase(ALT), aspartate aminotransferase(AST), reactive oxygen species(ROS), tumor necrosis factor alpha(TNF-α), interleukin-1 beta(IL-1β), cyclooxygenase-2(COX-2), IL-6, IL-4, IL-10, as well as lactate dehydrogenase(LDH), glutathione(GSH), superoxide dismutase(SOD), catalase(CAT), total antioxidant capacity(T-AOC), malondialdehyde(MDA), and myeloperoxidase(MPO) liver tissue. Hematoxylin-eosin staining was used to observe the morphological changes of liver tissue. The mRNA expression levels of lymphocyte antigen 6G(Ly6G), galectin 3(Mac-2), TNF-α, IL-1β, COX-2, IL-6, IL-4, and IL-10 in liver tissue were determined by quantitative real-time polymerase chain reaction(PCR). Western blot was utilized to detect the protein expression levels of Ly6G, Mac-2, extracellular regulated protein kinases(ERK), phosphorylated extracellular regulated protein kinases(p-ERK), COX-2, inhibitor of nuclear factor κB protein α(IκBα), phosphorylated inhibitor of nuclear factor κB protein α(p-IκBα), and nuclear factor-κB subunit p65(NF-κB p65) in cytosol and nucleus in liver tissue. The results manifested that TSPJ dramatically reduced liver coefficient, serum ALT, AST, ROS, TNF-α, IL-1β, IL-6, and COX-2 levels, LDH, MPO, and MDA contents in liver tissue, and mRNA expressions of TNF-α, IL-1β, and IL-6 in APAP-induced liver injury mice. It prominently elevated serum IL-4 and IL-10 levels, GSH, CAT, SOD, and T-AOC contents, and mRNA expressions of IL-4 and IL-10 in liver tissue, improved the degree of liver pathological damage, and suppressed neutrophil infiltration and macrophage recruitment in liver tissue. In addition, TSPJ lessened the mRNA and protein expressions of neutrophil marker Ly6G, macrophage marker Mac-2, and COX-2 in liver tissue, protein expressions of p-ERK, p-IκBα, and NF-κB p65 in nuclear, and p-ERK/ERK and p-IκBα/p-IκBα ratios and hoisted protein expression of NF-κB p65 in cytosol. These results suggest that TSPJ has a significant protective effect on APAP-induced liver injury in mice, and it can alleviate APAP-induced oxidative damage and inflammatory response. Its mechanism may be related to suppressing ERK/NF-κB/COX-2 signaling pathway activation, thus inhibiting inflammatory cell infiltration, cytokine production, and liver cell damage.

This study investigated the protective effect of total triterpenoids from Chaenomeles speciosa against Helicobacter pylori(Hp)-induced gastritis in mice and explored its possible mechanism. The chronic atrophic gastritis(CAG) model mice were randomly divided into four groups of model, total triterpenoids from C. speciosa(50 and 100 mg·kg~(-1)) and triple therapy, with C57 BL/6 J mice without Hp infection taken as the normal group. Mice in the treatment groups were given corresponding drugs once a day for 4 weeks. Then the following indexes were detected: the contents of reactive oxygen species(ROS), monocyte chemotactic protein 1(MCP-1), keratinocyte chemokines(KC), TNF-α, IL-1β, IL-6, IL-18, IL-4 and IL-10 in blood and gastric tissue, the activities and contents of LDH, MPO, SOD, GSH-Px, CAT and MDA in gastric tissue and the activities of β-glucuronidase, β-galactosidase, cathepsins B and D in blood, gastric tissue and lysosome. Besides, the mRNA expression levels of Toll-like receptor 4(TLR4), myeloid differentiation factor 88(MyD88), Bcl-2, Bcl-xl, Bax and Bad in gastric tissue were determined by quantitative real-time PCR. Western blot was employed to detect the protein expression levels of TLR4, MyD88, p-IKKβ, p-IκBα, NOD-like receptor 3(NLRP3), apoptosis-associated speck-like protein(ASC), pro-caspase-1, caspase-1, thioredoxin-interacting protein(TXNIP), pro-IL-1β, pro-IL-18, Bcl-2, Bcl-xl, Bax, Bad, cytochrome C, apoptotic protease-activating factor-1(Apaf-1), pro-caspase-9, pro-caspase-3, cleaved-caspase-9, cleaved-caspase-3, poly(ADP-ribose) polymerase 1(PARP-1), cleaved-PARP-1 and cytosol and nucleus NF-κB p65 in gastric tissue. The results indicated that the total triterpenoids from C. speciosa significantly suppressed Hp proliferation, alleviated the damage to gastric mucosa and improved lymphocyte infiltration and gland atrophy. They were also effective in reducing the activities of β-glucuronidase, β-galactosidase, cathepsins B and D in blood and gastric tissue, elevating the activities of β-glucuronidase and cathepsin D in lysosomal organelles, decreasing the contents of ROS, MCP-1, KC, TNF-α, IL-1β, IL-6, IL-18 in blood, MDA content and MPO and LDH activities in gastric tissue and increasing the contents of IL-4 and IL-10 in blood and activities of SOD, CAT and GSH-Px in gastric tissue. Other phenomena were also observed after the treatment with total triterpenoids from C. speciosa, including the down-regulation of the mRNA and protein expression levels of TLR4, MyD88, Bax and Bad, the protein expression levels of p-IKKβ, p-IκBα, NLRP3, ASC, pro-caspase-1, caspase-1, TXNIP, pro-IL-1β, pro-IL-18, cytochrome C, Apaf-1, cleaved-caspase-9, cleaved-caspase-3, cleaved-PARP-1 and nuclear NF-κB p65, reduction of p-IKKβ/IKKβ and p-IκBα/IκBα ratios and up-regulation of the mRNA and protein expression levels of Bcl-2 and Bcl-xl, up-regulation of pro-caspase-9, pro-caspace-3, cytosol NF-κB p65 protein expression levels and Bcl-2/Bax and Bcl-xl/Bad ratios in gastric tissue. These aforementioned results suggest that the total triterpenoids from C. speciosa have significant protective effects against CAG induced by Hp, and its mechanism may be related to enhancing the function of endogenous antioxidant system, suppressing the oxidative stress and inflammatory reaction induced by Hp, correcting lysosomal dysfunction and inflammatory activation of TLR4/NF-κB/NLRP3 inflammasome signaling pathway and thus inhibiting mitochondria-mediated apoptosis.

Population dynamics of an insect can be affected by its life-history traits. Understanding of the life-history variations among geographical populations of an insect pest is important for developing the corresponding control strategies in different regions. Rhopalosiphum padi is a cosmopolitan cereal pest, and life-history traits identification of R. padi from different geographical regions is rare. Here, we experimentally evaluated variations in the life histories and life-table parameters of R. padi populations from six widely ranging geographical regions, including Baoding (HB), Xianyang (SX), Nanyang (HN), Wuhan (HW), Beibei (CB), and Guiyang (GG), in China. Total longevity was similar for HB, CB, and GG populations and generally shorter than that of the SX, HN, and HW populations. The age at first reproduction of HB and HW populations was significantly different from that of the other four populations. Mean fecundity of the SX population was significantly higher than that of the other five populations, and the mean fecundity of the GG population was the lowest. Principal component analysis (PCA) also showed that the life-history and life-table parameters of R. padi differed among the six geographical populations. According to PCA results, the HW population was in one cluster; the GG population was in another cluster; the SX, HN, and CB populations were in one cluster; and the HB population differed from the above three clusters. The complexity of local genetic adaptation in aphids was discussed. The current results will likely be of importance to management practices and population dynamics forecasting of R. padi., (© The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Hypoxia-inducible factor 1-alpha (HIF-1α) is a subunit of HIF-l and thought to be able to protect hypoxic cells from apoptosis or necrosis under ischemic and anoxic conditions. This study aimed to investigated whether recombinant adenovirus vector over-expressing HIF-lα could affect apoptosis-related proteins (Bcl-2 and Bax) and vascular endothelial growth factor (VEGF) in a rat spinal cord injury (SCI) model. A total of 60 male SD rats were divided into 4 groups: Sham, Control, Ad-Blank and Ad-HIF-1α groups. 1, 3, 7, 14, 28 days after surgery, the behavioral recovery was evaluated with BBB scales. Then, rats were sacrificed and the spinal cord was collected for detection of Bcl-2, Bax and VEGF expressions by immunohistochemistry. Results showed the Bcl-2, Bax, VEGF and HIF-lα expressions increased in animals with SCI, but the increase in Bcl-2, VEGF and HIF-lα expressions were higher in Ad-HIF-1α group when compared with other groups, but Bax expression decreased significantly. In addition, administration of Ad-HIF-1α significantly reduced apoptotic cells and promoted the recovery of neurological function. In conclusion, administration of Ad-HIF-1α after SCI could ameliorate neuronal apoptosis and promote angiogenesis in rats. Our study provides a basis for further exploration of the relationship between HIF1α and SCI.