Involvement of dorsal hippocampal muscarinic cholinergic receptors on muscimol state-dependent memory of passive avoidance in mice

AimsIn the present study, the effects of bilateral intra-dorsal hippocampal (intra-CA1) injections of cholinergic agents on muscimol state-dependent memory were examined in mice.Main methodsA single-trial step-down passive avoidance task was used for the assessment of memory retention in adult male NMRI mice.Key findingsPre-training intra-CA1 administration of a GABA-A receptor agonist, muscimol (0.05 and 0.1 μg/mouse) dose dependently induced impairment of memory retention. Pre-test injection of muscimol (0.05 and 0.1 μg/mouse, intra-CA1) induced state-dependent retrieval of the memory acquired under pre-training muscimol (0.1 μg/mouse, intra-CA1) influence. Pre-test intra-CA1 injection of an acetylcholinesterase inhibitor, physostigmine (0.5 and 1 μg/mouse, intra-CA1) reversed the memory impairment induced by pre-training administration of muscimol (0.1 μg/mouse, intra-CA1). Moreover, pre-test administration of physostigmine (0.5 and 1 μg/mouse, intra-CA1) with an ineffective dose of muscimol (0.025 μg/mouse, intra-CA1) significantly restored the retrieval and induced muscimol state-dependent memory. Pre-test intra-CA1 administration of physostigmine (0.25, 0.5 and 1 μg/mouse) by itself cannot affect memory retention. Pre-test intra-CA1 injection of the muscarinic receptor antagonist, atropine (1 and 2 μg/mouse) 5 min before the administration of muscimol (0.1 μg/mouse, intra-CA1) dose dependently inhibited muscimol state-dependent memory. Pre-test intra-CA1 administration of atropine (0.5, 1 and 2 μg/mouse) by itself cannot affect memory retention.SignificanceThe results suggest that muscarinic cholinergic mechanism of the CA1 may influence muscimol state-dependent memory.     

In vitro antifungal activity of ajoene on five clinical isolates of Histoplasma capsulatum var. capsulatum

BackgroundThe number of histoplasmosis cases have considerably increased since the advent of AIDS, and the therapy for this mycosis is not always effective, as well as having adverse effects.AimsTo evaluate the inhibitory effect of ajoene on five clinical isolates of Histoplasma capsulatum, on the mycelial form, using Sabouraud dextrose broth (SDB) and RPMI-1640 culture media.MethodsGrowth curves and inhibitory activity of the drug (at concentrations of 1.25 ug/ml to 20 μg/ml) were performed at room temperature, under mechanical agitation, and the turbidimetric readings (540 nm) were recorded every 48 h for 14 days, in both culture media. Generation times (GT) were calculated and graphs were constructed to estimate Minimal Inhibitory Concentrations (MIC) and Inhibitory Concentration 50% (IC₅₀). The fungicidal minimal concentrations (FMC) were determined by plate cultures. The U-Mann-Whitney and t-test with a significance level of 0.05 were used to evaluate the statistical significance between culture media and GT, MIC, IC₅₀ MFC and fungistatic effect (FE).ResultsIn both media and for all isolates, growth curves showed a GT of 43 to 67 hrs, an FE at 1.25-2.5 μg/ml, and a MFC at 5-10 μg/ml of ajoene. Values of MIC were 2.5-5 in SDB and in RPMI medium these values were 1.25-5 μg/ml of ajoene. For IC₅₀, in SDB, the values were 1.9-2.6 ug/ml and in RPMI medium, they were of 3.8-4.3 μg/ml of ajoene. There were no significance differences between culture media for GT, FE, MIC, IC₅₀ and MFC (p > 0.05).ConclusionsThese findings corroborate that ajoene inhibits the growth of the mycelial form of H. capsulatum.     

PCSK2-null mice exhibit delayed intestinal motility, reduced refeeding response and altered plasma levels of several regulatory peptides

AimsTo examine the effects of global lack of proprotein convertase subtilisin/kexin 2 (PCSK2) in mouse on intestinal motility, post-fast refeeding response and levels of several PCSK-generated peptides known to regulate food intake and processing.Main methodsUsing male and female PCSK2 knockout (KO) and wild-type (WT) mice, intestinal motility was assessed by determining the percent of intestinal length travelled by a charcoal-dyed meal following an oral gavage; the refeeding response by measuring the amount of meal consumed following an overnight fast; the levels of the regulatory peptides by enzyme immunoassays or immunoblotting.Key findingsRelative to same-gender WT mice, KO mice exhibited delayed intestinal transit (P < 0.001 in females; P < 0.05 in males). Their post-fast feeding response was reduced in females during the first hour of refeeding (P < 0.05). The circulating level of substance P (SP) was lower (P < 0.001 in females; P < 0.05 in males); it was higher for somatostatin (SS) (P < 0.001 in females; P < 0.05 in males) and GLP-1 (P < 0.001 in females; P < 0.01 in males) and GLP-2 (P < 0.001 in both genders); it was higher for peptide YY (PYY) in female mice only (P < 0.01). Processing of brain proneuropeptide Y was impaired in both genders.SignificanceThe alterations in intestinal motility and post-fast refeeding response observed in PCSK2-KO mice correlate with changes in the circulating and tissue levels of the regulatory peptides tested, suggesting that PCSK2 is needed for normal food intake and processing.     

Propofol decreases the axonal excitability in rat primary sensory afferents

AimsThe aim of this present study was to investigate the changes of peripheral sensory nerve excitability produced by propofol.Main methodsIn a recently described in vitro model of rodent saphenous nerve we used the technique of threshold tracking (QTRAC®) to measure changes of axonal nerve excitability of Aβ-fibres caused by propofol. Concentrations of 10 μMol, 100 μMol and 1000 μMol were tested. Latency, peak response, strength-duration time constant (τSD) and recovery cycle of the sensory neuronal action potential (SNAP) were recorded.Key findingsOur results have shown that propofol decreases nerve excitability of rat primary sensory afferents in vitro. Latency increased with increasing concentrations (0 μMol: 0.96 ± 0.07 ms; 1000 μMol 1.10 ± 0.06 ms, P < 0.01). Also, propofol prolonged the relative refractory period (0 μMol: 1.79 ± 1.13 ms; 100 μMol: 2.53 ± 1.38 ms, P < 0.01), and reduced superexcitability (0 μMol: ? 14.0 ± 4.0%; 100 μMol: ? 9.5 ± 5.5%) and subexcitability (0 μMol: 7.5 ± 1.2%; 1000 μMol: 3.6 ± 1.2) significantly during the recovery cycle (P < 0.01).SignificanceOur results have shown that propofol decreases nerve excitability of primary sensory afferents. The technique of threshold tracking revealed that axonal voltage-gated ion channels are significantly affected by propofol and therefore might be at least partially responsible for earlier described analgesic effects.     

In vitro activity of 5-(2,4-dimethylbenzyl) pyrrolidin-2-one extracted from marine Streptomyces VITSVK5 spp. against fungal and bacterial human pathogens

BackgroundPharmacological screening and usage of natural products for the treatment of human diseases has had a long history from traditional medicine to modern drugs. The majority of modern drugs are reported to be mostly from natural products.ObjectiveThe aim of the present study was to evaluate the inhibitory activity of 5-(2,4-dimethylbenzyl) pyrrolidin-2-one (DMBPO) extracted from marine Streptomyces VITSVK5 spp. isolated from sediment samples collected at Marakkanam coast of Bay of Bengal, India.MethodsThe lead compound was isolated by bioactive guided extraction and purified by silica gel column chromatography. Structural elucidation of the lead compound was carried out by using UV, FT-IR, ¹H NMR, ¹³C NMR, DEPT and HR-MS spectral data.ResultsSystematic screening of isolates for antimicrobial activity lead to identification of a potential strain, Streptomyces VITSVK5 spp. (GQ848482). Bioactivity guided extraction yielded a compound DMBPO and its inhibitory activity was tested against selected bacterial and fungal strains. DMBPO showed maximal activity against Escherichia coli with a MIC value of 187 μg/ml, followed by Klebsiella pneumoniae (MIC of 220 μg/ml and 10.3 mm zone of inhibition), Staphylococcus aureus (MIC of >1000 μg/ml and 4.4 mm zone of inhibition) and Bacillus subtilis (MIC of 850 μg/ml and 2.6 mm zone of inhibition). Furthermore, DMBPO was found to be a potent inhibitor of opportunistic fungal pathogens too. It showed a maximum activity against Aspergillus niger with a MIC value of 1 μg/ml and 28 mm zone of inhibition.ConclusionThe result of this study indicates that DMBPO possess antibiotic activity to selected bacterial and fungal pathogens and exhibited better activity against fungi than bacteria.     

Relationships of serum thyroid hormones and follicle-stimulating hormone concentrations to Sertoli cell differentiation during the first wave of spermatogenesis in euthyroid ram lambs

The main purpose of this study was to determine if temporal relationships exist between serum concentrations of free fractions of thyroxin (fT₄) and triiodothyronine (fT₃), follicle-stimulating hormone (FSH) levels, and Sertoli cell differentiation in euthyroid ram lamb testes. Additionally, testicular thyroid hormone (TH) receptors (TRs) were identified using immunohistochemistry and Western blot analysis. Weekly testicular biopsies and jugular blood samples were collected from 12 ram lambs over the 9 weeks of study. Hormone concentrations and the numbers of dividing Sertoli cells per seminiferous tubule (ST) area were analyzed relative to chronological age of animals and the two distinctive stages of Sertoli cell differentiation: (a) tight junction/ST lumen formation and (b) the onset of support mechanisms for the development of multiple germ cell types (presence of primary spermatocytes in >95% STs). Circulating FSH concentrations increased (p < 0.05) immediately after first detection of ST lumen and reached a nadir (p < 0.05) just prior to the end of the first wave of spermatogenesis. A decline in both fT₄ and fT₃ levels (p < 0.05) occurred after Sertoli cells had formed the ST lumen and began supporting germ cell differentiation. There was a positive correlation between the numbers of proliferating Sertoli cells and serum fT₄ (r = 0.51, p < 0.001) and fT₃ (r = 0.52, p < 0.001) concentrations. TRs were expressed throughout the study period; however, prior to the formation of ST lumen, two isoforms were detected while only one TR isoform was present by the end of the first wave of spermatogenesis. Overall, the exit of Sertoli cells from the cell cycle that presages their final differentiation begins when THs and FSH levels are high, suggesting a permissive role of these hormones in the maturation of STs in prepubertal ram lambs.     

Aclidinium bromide, a novel long-acting muscarinic antagonist for COPD with improved preclinical renal and urinary safety profile

AimsAclidinium bromide is a novel, long-acting, inhaled muscarinic antagonist currently in registration phase for the treatment of chronic obstructive pulmonary disease. Since urinary difficulty and retention have been reported for anticholinergic agents such as tiotropium and ipratropium, it is important to examine the preclinical urinary and renal safety profile of aclidinium.Main methodsThe effect of aclidinium on urine and electrolyte excretion, renal function and voiding cystometry was analysed in conscious water-loaded Wistar rats (10–1000 μg/kg, s.c.), anaesthetised Beagle dogs (1000 μg/kg, i.v.) and anaesthetised guinea pigs (3–100 μg/kg, intratracheally), respectively. Aclidinium plasma levels were determined in an independent study. Active comparators were tiotropium (all studies) and ipratropium (cystometry only).Key findingsAclidinium 1000 μg/kg had no effect on urine excretion in rats, in contrast to tiotropium 100 μg/kg which significantly decreased this parameter (p < 0.05). Aclidinium 1000 μg/kg also had no effect on renal function in Beagle dogs. In guinea pigs, aclidinium 3–100 μg/kg had no effect on urinary bladder function, whereas tiotropium and ipratropium 100 μg/kg decreased the peak micturition pressure (p < 0.05), increased the volume of urine retained in the bladder (p < 0.01) and showed a trend to decrease the volume of urine excreted.SignificanceAclidinium had no significant effect on urinary and renal function in the animal models studied. These results, together with the rapid plasma clearance of aclidinium reported previously, suggest a lower propensity to induce urinary retention in humans than tiotropium and ipratropium.     

Involvement of NO-guanylyl cyclase pathway for the depression of spinal monosynaptic reflex by Mesobuthus tamulus venom in neonatal rat in vitro

AimsThe present study was undertaken to evaluate the role of nitric oxide (NO) in Mesobuthus tamulus (MBT) venom-induced depression of spinal reflexes.Main methodsExperiments were performed on isolated hemisected spinal cords from 4 to 6 day old rats. Stimulation of a dorsal root with supramaximal strength evoked monosynaptic (MSR) and polysynaptic reflex (PSR) potentials in the corresponding segmental ventral root.Key findingsSuperfusion of MBT venom (0.3 μg/ml) depressed the spinal reflexes in a time-dependent manner and the maximum depression was seen at 10 min (MSR by 63%; PSR by 79%). The time to produce 50% depression (T-50) of MSR and PSR was 7.7 ± 1.3 and 5.7 ± 0.5 min, respectively. Pretreatment with bicuculline (1 μM; GABA_A receptor antagonist) or strychnine (1 μM; glycine_A receptor antagonist) did not block the venom-induced depression of spinal reflexes. However, Nω-nitro-L-arginine methyl ester (L-NAME, 100 or 300 μM; NO synthase inhibitor) or hemoglobin (Hb, 100 μM; NO scavenger) antagonized the venom-induced depression of MSR. Further, soluble guanylyl cylase inhibitors (1 H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one, ODQ; 1 μM or methylene blue, 100 μM) also antagonized the venom-induced depression of MSR but not PSR. Nitrite concentration (indicator of NO activity) of the cords exposed to venom (0.3 μg/ml) was not different from the control group.SignificanceThe results indicate that venom-induced depression of MSR is mediated via NO-guanylyl cyclase pathway without involving GABAergic or glycinergic system.     

Expression of BMP-receptor type 1A correlates with progress of osteoarthritis in human knee joints with focal cartilage lesions

Background aimsBone morphogenetic protein-2 (BMP-2) and its receptor type 1A (BMPR-1A) play significant roles in cartilage metabolism. The aim of this study was to evaluate a possible correlation between intra-articular expression of these proteins and the degree of osteoarthritis (OA) in human knees.MethodsBiopsies of synovia and debrided cartilage were taken in 15 patients undergoing autologous chondrocyte implantation. Expression of BMP-2 and BMPR-1A was evaluated semi-quantitatively by immunohistologic staining. These data were complemented by grading of cartilage lesions according to International Cartilage Repair Society (ICRS), defect size, duration of complaints, knee osteoarthritis scoring system (KOSS) and Henderson and Kellgren–Lawrence scores. General histologic stainings were used to determine Mankin, Pritzker and Krenn scores.ResultsThe expression of BMPR-1A but not of BMP-2 was significantly higher in cartilage biopsies taken in type 3 lesions with intact subchondral layer compared with type 4 defects (P < 0.05). In cartilage areas of bordering sectors, the intensity of immunohistologic staining of BMPR-1A was statistically significantly higher in mature cartilage compared with repair zones (P < 0.05). Expression of BMP-2 and its receptor 1A correlated in the cartilage biopsies (P < 0.02) but not in the synovia. The degree of OA was scored in all biopsies according to Mankin and Pritzker, and these scores correlated statistically significantly with BMPR-1A expression in the synovia (P < 0.05). In patients with an osteochondritis dissecans, the degree of OA was higher compared with other causes of chondromalacia, as evaluated by defect size, ICRS score, duration of complaints, Pritzker score and expression of BMPR-1A in cartilage (P < 0.05).ConclusionsThese data support the role of BMPR-1A as an indicator of OA progression in human knees with circumscribed cartilage lesions.     

μ1- and 5-HT1-dependent mechanisms in the anterior pretectal nucleus mediate the antinociceptive effects of retrosplenial cortex stimulation in rats

AimThis study examines if injection of cobalt chloride (CoCl₂) or antagonists of muscarinic cholinergic (atropine), μ₁-opioid (naloxonazine) or 5-HT₁ serotonergic (methiothepin) receptors into the dorsal or ventral portions of the anterior pretectal nucleus (APtN) alters the antinociceptive effects of stimulating the retrosplenial cortex (RSC) in rats.Main methodChanges in the nociceptive threshold were evaluated using the tail flick or incision pain tests in rats that were electrically stimulated at the RSC after the injection of saline, CoCl₂ (1 mM, 0.10 μL) or antagonists into the dorsal or ventral APtN.Key findingsThe injection of CoCl₂, naloxonazine (5 μg/0.10 μL) or methiothepin (3 μg/0.10 μL) into the dorsal APtN reduced the stimulation-produced antinociception from the RSC in the rat tail flick test. Reduction of incision pain was observed following stimulation of the RSC after the injection of the same substances into the ventral APtN. The injection of atropine (10 ng/0.10 μL) or ketanserine (5 μg/0.10 μL) into the dorsal or ventral APtN was ineffective against the antinociception resulting from RSC stimulation.Significanceμ₁-opioid- and 5-HT₁-expressing neurons and cell processes in dorsal and ventral APtN are both implicated in the mediation of stimulation-produced antinociception from the RSC in the rat tail flick and incision pain tests, respectively.     

The perioperative granulocyte/lymphocyte ratio is a clinically relevant marker of surgical stress in patients with colorectal cancer

PurposeThis study was to assess the clinical relevance of the blood granulocytes to lymphocytes (G/L) ratio as an early marker of surgical stress in patients with colorectal cancer.MethodsThirty-three patients with colorectal cancer were prospectively to undergo laparoscopic-assisted (n = 12) or open (n = 21) surgical resection. Granulocyte and lymphocyte counts were used to calculate the G/L ratios in blood samples from all patients before the operation and post-operatively on days 1, 3 and 7. Additionally, serum inflammatory cytokines, interleukin (IL)-1β, IL-6, IL-8, tumour necrosis factor (TNF)-α, granulocyte colony-stimulating factor (G-CSF) and macrophage (M)-CSF were assayed as markers of surgical stress.ResultsSeven of 33 patients developed unexpected complications. Serum IL-6 (P < 0.0001), G-CSF (P = 0.0257), and M-CSF (P < 0.0001) were higher on day 1 vs before the operation. Similarly, the G/L ratios were higher on days 1–3 vs before the operation (P < 0.0001) and then gradually decreased together with the surgical stress levels. The G/L ratios and the numbers of granulocytes and lymphocytes in the blood showed no correlation with serum IL-1β or TNF-α. In contrast, the G/L ratios and the numbers of granulocytes in the blood showed significant correlation with IL-6 (Rs = 0.710, P < 0.0001, Rs = 0.653, P < 0.0001, respectively), with G-CSF (Rs = 0.626, P < 0.0001, Rs = 0.578, P < 0.0001), with M-CSF (Rs = 0.470, P < 0.0001, Rs = 0.372, P < 0.0001). However, the number of lymphocytes showed inverse correlation with IL-6 (Rs = ?0.493, P < 0.0001), G-CSF (Rs = ?0.440, P < 0.0001) and M-SCF (Rs = ?0.443, P < 0.0001).ConclusionThe G/L ratio appears to be a simple and clinically relevant parameter for the assessment of perioperative stress in patients undergoing colorectal surgery.     

Cytokine-induced killer cells in the treatment of patients with solid carcinomas: a systematic review and pooled analysis

Background aimsThe aim of this study was to evaluate the efficacy and safety of cytokine-induced killer (CIK) cell therapy for solid carcinomas.MethodsWe performed a computerized search of phase II/III clinical trial databases of CIK cell-based therapy using a combination of the terms ‘cytokine-induced killer cells’, ‘tumor’ and ‘cancer’.ResultsTreatment with CIK cells was associated with a significantly improved half-year survival (P = 0.003), 1-year survival (P = 0.0005), 2-year survival (P  < 0.01) and mean survival time (MST) (P  < 0.001). Patients in the CIK group showed a prolonged half-year progression-free survival (PFS) (P  < 0.01), 1-year PFS (P < 0.01) and median time to progression (MTTP) (P < 0.001). A favored disease control rate (DCR) was observed in patients receiving CIK cell therapy, while the objective response rate (ORR) was not altered (P = 0.05) compared with the non-CIK group (P = 0.007). CIK cell therapy could also reduce the adverse effects of grade III and IV leukopenia caused by chemotherapy (P = 0.002) and diminish hepatitis B virus (HBV)-DNA content (P < 0.01). However, the incidence of fever in the CIK therapy group was significantly higher than in the non-CIK group (P = 0.02). The percentage of CD3⁺, CD4⁺, CD4⁺ CD8⁺, CD3^? CD56⁺ and CD3⁺ CD56⁺ T-lymphocyte subsets in the peripheral blood of cancer patients was significantly increased, whereas the percentage of CD8⁺ T-lymphocyte cells was significantly decreased in the CIK group compared with the non-CIK group (P < 0.01).ConclusionsCIK cell therapy has demonstrated a significant superiority in prolonging the MST, PFS, DCR and quality of life (QoL) of patients.     

The vastus lateralis neuromuscular activity during all-out cycling exercise

ObjectiveThe objective of this work was to study modifications in motor control through surface electromyographic (sEMG) activity during a very short all-out cycling exercise.MethodsTwelve male cyclists (age 23 ± 4 years) participated in this study. After a warm-up period, each subject performed three all-out cycling exercises of 6 s separated by 2 min of complete rest. This protocol was repeated three times with a minimum of 2 days between each session. The braking torque imposed on cycling motion was 19 N m. The sEMG of the vastus lateralis was recorded during the first seven contractions of the sprint. Time–frequency analysis of sEMG was performed using continuous wavelet transform. The mean power frequency (MPF, qualitative modifications in the recruitment of motor units) and signal energy (a quantitative indicator of modifications in the motor units recruitment) were computed for the frequency range 10–500 Hz.ResultssEMG energy increased (P ? 0.05) between contraction number 1 and 2, decreased (P ? 0.05) between contraction number 2 and 3 then stabilized between contraction number 3 and 7 during the all-out test. MPF increased (P ? 0.05) during the all-out test. This increase was more marked during the first two contractions.ConclusionsThe decrease in energy and the increase in the sEMG MPF suggest a large spatial recruitment of motor units (MUs) at the beginning of the sprint followed by a preferential recruitment of faster MUs at the end of the sprint, respectively.     

Effectiveness of liposomal buparvaquone in an experimental hamster model of Leishmania (L.) infantum chagasi

The objective of this study was to develop a novel liposomal formulation, containing phosphatidylserine (PS), of buparvaquone (BPQ) and to evaluate its in vivo effectiveness in Leishmania (L.) infantum chagasi-infected hamsters. The activity of BPQ was evaluated against both the promastigote forms of different Leishmania species and the intracellular amastigotes of L. (L.) infantum chagasi. Buparvaquone was entrapped in PS-liposomes (BPQ–PS-LP), and the drug was quantified by ultra-high-performance liquid chromatography. The treatment was quantified by detecting the RNA of the living amastigotes in the spleen and the liver by real-time PCR. In vitro assays with L. (L.) infantum chagasi intracellular amastigotes were performed in peritoneal macrophages for the evaluation of the 50% inhibitory concentration (IC₅₀). BPQ–PS-LP at 0.33 mg/kg/day for eight consecutive days reduced the number of amastigotes by 89.4% (P < 0.05) in the spleen and by 67.2% (P > 0.05) in the liver, compared to 84.3% (P < 0.05) and 99.7% (P < 0.05), respectively, following Glucantime® treatment at 50 mg/kg/day. Free BPQ at 20 mg/kg/day failed to treat the hamsters when compared to the untreated group. BPQ was significantly (P < 0.05) selective against L. (L.) infantum chagasi intracellular amastigotes, with an IC₅₀ value of 1.5 μM; no in vitro mammalian cytotoxicity could be detected. Other cutaneous species were also susceptible to BPQ, with IC₅₀ values in the range 1–4 μM. BPQ–PS-LP caused a significant reduction in the parasite burden at a 60-fold lower dose than did the free BPQ. These results show the potential of PS-liposome formulations for the successful targeted delivery of BPQ in visceral leishmaniasis.     

Improved survival of mesenchymal stromal cell after hypoxia preconditioning: role of oxidative stress

AimsTo investigate the mechanisms underlying the beneficial effect of hypoxia preconditioning (HPC) on mesenchymal stromal cells (MSCs) and optimize novel non-invasive methods to assess the effect of biological interventions aimed to increased cell survival.Main methodsMSCs from rat femur, with or without HPC, were exposed to hypoxic conditions in cell culture (1% O₂ for 24 h) and cell survival (by the LDH release assay and Annexin-V staining) was measured. Oxidant status (conversion of dichloro-fluorescein-DCF- and dihydro-ethidium-DHE-, protein expression of oxidant enzymes) was characterized, together with the mobility pattern of cells under stress. Furthermore, cell survival was assessed non-invasively using state-of-the-art molecular imaging.Key findingsCompared to controls, Hypoxia resulted in increased expression of the oxidative stress enzyme NAD(P)H oxidase (subunit 67^phox: 0.05 ± 0.01 AU and 0.48 ± 0.02 AU, respectively, p < 0.05) and in the amount of ROS (DCF: 13 ± 1 and 42 ± 3 RFU/μg protein, respectively, p < 0.05) which led to a decrease in stem cell viability. Hypoxia preconditioning preserved cell biology, as evidenced by preservation of oxidant status (16 ± 1 RFU/μg protein, p < 0.05 vs. hypoxia), and cell viability. Most importantly, the beneficial effect of HPC can be assessed non-invasively using molecular imaging.SignificanceHPC preserves cell viability and function, in part through preservation of oxidant status, and its effects can be assessed using state-of-the-art molecular imaging. Understanding of the mechanisms underlying the fate of stem cells will be critical for the advancement of the field of stem cell therapy.     

Fluoxetine, 17-β estradiol or folic acid combined with intra-lateral septal infusions of neuropeptide Y produced antidepressant-like actions in ovariectomized rats forced to swim

Folic acid is antidepressant, either alone or combined with several antidepressant drugs. However, the antidepressant-like actions of folic acid combined with intra-lateral septal (LSN) infusions of neuropeptide Y (NPY) in the forced swimming test (FST) have not been tested before. Thus, systemic injections of fluoxetine (20.0 mg/kg, P < 0.05; s.c.) or 17-β estradiol (10.0 μg/rat, P < 0.05; s.c.) or oral administrations of folic acid (50.0 mg/kg, P < 0.05; 75.0 mg/kg, P < 0.05) or NPY intra-LSN (3.0 μg, P < 0.05; 3.5 μg, P < 0.05) reduced immobility of ovariectomized Wistar rats. Subthreshold doses of: folic acid (25.0 mg/kg) or 17-β estradiol (5.0 μg/rat, P < 0.05) or fluoxetine (15.0 mg/kg, P < 0.05; s.c.) combined with subthreshold doses of NPY (2.5 μg/rat, P < 0.05; intra-LSN) and these combinations produced antidepressant-like actions; which were canceled by BIBP 3226 (a NPY-Y1 receptor antagonist). It is concluded that folic acid produced antidepressant-like effects probably through the participation of the NPY Y1 receptors found in the lateral septal nuclei.     

Effect of transcatheter renal arterial embolization combined with cryoablation on regulatory CD4+CD25+ T lymphocytes in the peripheral blood of patients with advanced renal carcinoma

ObjectiveTo analyze the effect of Argon-Helium cryosurgery (AHCS) combined with transcatheter renal arterial embolization (TRAE) on the differentiation of regulatory CD4⁺ CD25⁺ T cell (Treg) and its implication in patients with renal carcinoma.MethodsSeventy seven patients are included in the study, and divided into two groups: TRAE group (n = 45, receiving TRAE only) and TRAE + cryoablation group (n = 32, receiving cryoablation 2–3 weeks after TRAE). The percentage of Treg cells and T lymphocyte subsets (CD4⁺T, CD8⁺T, and CD4⁺T/CD8⁺T) in the peripheral blood is measured by flow cytometry previous to the therapy and 3 months after therapy. Meanwhile, the extent of tumor necrosis is measured by MRI or CT 1 month after therapy.ResultsThe percentages of Treg cells of patients in TRAE + cryoablation group decrease from (6.65 ± 1.22)% to (3.93 ± 1.16)%, (t = 42.768, P < 0.01), and the percentages of CD4⁺T and CD4⁺T/CD8⁺T increase significantly (P < 0.01). However, the results of patients in TRAE group show that the percentages of Treg, CD4⁺T, CD8⁺T and CD4⁺T/CD8⁺T increase slightly although the differences had no statistical significance (P > 0.05). The tumor necrosis rate of TRAE + cryoablation group is 57.5%, significantly higher than those of TRAE group, which shows 31.6% (t = 6.784, P < 0.01). The median survival duration of the TRAE + cryoablation group is 20 months, significantly longer than that of the TRAE group (χ² = 7.368, P < 0.01). The decreasing extent of Treg cells is correlated with tumor necrosis rates (r = 0.90, P < 0.01) and life time (r = 0.67, P < 0.01).ConclusionThe therapy of TRAE combined with cryoablation contributes to reduce the percentage of Treg cells and improve the immune situation of patients with renal cell carcinoma, which consequently increase tumor necrosis rate and prolong the patients‘ survival duration.     

Endogenous cannabinoid receptor agonist anandamide induces peripheral antinociception by activation of ATP-sensitive K+ channels

AimsThe effects of several potassium (K⁺) channel blockers were studied to determine which K⁺ channels are involved in peripheral antinociception induced by the cannabinoid receptor agonist, anandamide.Main methodsHyperalgesia was induced by subcutaneous injection of 250 μg carrageenan into the plantar surface of the hind paw of rats. The extent of hyperalgesia was measured using a paw pressure test 3 h following carrageenan injection. The weight in grams (g) that elicited a nociceptive response, paw flexion, during the paw pressure test was used as the nociceptive response threshold.Key findingsDoses of 50, 75, and 100 ng of anandamide elicited a dose-dependent antinociceptive effect. Following a 100 ng dose of anandamide no antinociception was observed in the paw that was contralateral to the anandamide injection site, which shows that anandamide has a peripheral site of action. Pretreatment with 20, 40 and 80 μg AM251, a CB₁ receptor antagonist, caused a dose-dependent decrease in anandamide-induced antinociception, suggesting that the CB₁ receptor is directly involved in anandamide effect. Treatment with 40, 80 and 160 μg glibenclamide, an ATP-sensitive K⁺ channel blocker, caused a dose-dependent reversal of anandamide-induced peripheral antinociception. Treatment with other K⁺ channel antagonists, tetraethylammonium (30 μg), paxilline (10 μg) and dequalinium (50 μg), had no effect on the induction of peripheral antinociception by anandamide.SignificanceThis study provides evidence that the peripheral antinociceptive effect of the cannabinoid receptor agonist, anandamide, is primarily caused by activation of ATP-sensitive K⁺ channels and does not involve other potassium channels.     

Sphingomyelin synthase 2 over-expression induces expression of aortic inflammatory biomarkers and decreases circulating EPCs in ApoE KO mice

AimsThis study sought to assess the effect of sphingomyelin synthase 2 (SMS2) over-expression on plaque component and endothelial dysfunction in atherosclerosis.Main methodsWe generated recombinant adenovirus vectors containing human SMS2 cDNA (AdV-SMS2) or control gene GFP cDNA (AdV-GFP). Both AdVs were injected (i.v.) into ApoE KO mice to establish SMS2 over-expressing and control mice models, respectively. The mice were fed a high fat diet for 30 days. We then examined their plasma lipid levels, expression levels of aortic inflammatory biomarkers critical for the plaque's stability, and numbers of peripheral endothelial progenitor cells (EPC).Key findingsCompared with the control mice, SMS2 over-expression had significantly (1) increased aortic matrix metalloproteinase-2 (MMP-2), monocyte chemoattractant protein-1 (MCP-1), tissue factor (TF) and cyclooxygenase-2 (COX-2) mRNA levels (1.9-fold, 2.2-fold, 2.6-fold and 3.2-fold, respectively, P < 0.01) and protein levels (2.2-fold, 1.9-fold, 1.9-fold and 2.1-fold, respectively, P < 0.01); (2) increased MMP-2, COX-2 in situ expression in aortic root (2.6-fold and 2.3-fold, respectively, P < 0.01); (3) decreased aortic COX-1 mRNA levels (65%, P < 0.01) and protein levels (64%, P < 0.01); and (4) decreased CD34/KDR-positive cells (33%, P < 0.01), circulating angiogenic cells (CACs) (50%, P < 0.05), and colony forming units (CFUs) (40%, P < 0.05) in circulation.SignificanceSMS2 over-expression was probably associated with increased expression of aortic inflammatory biomarkers, as well as decreased numbers of CD34/KDR-positive cells, CACs and CFUs in circulation. Therefore, SMS2 over-expression might correlate with endothelial dysfunction and aggravate atherosclerotic plaque instability in ApoE KO mice.     

Exonuclease 1 (EXO1) gene variation and melanoma risk

ObjectiveDNA repair pathway genes play an important role in maintaining genomic integrity and protecting against cancer development. This study aimed to identify novel SNPs in the DNA repair-related genes associated with melanoma risk from a genome-wide association study (GWAS).MethodsA total of 8422 SNPs from the 165 DNA repair-related genes were extracted from a GWAS of melanoma risk, including 494 cases and 5628 controls from the Nurses’ Health Study (NHS) and the Health Professionals Follow-up Study (HPFS). We further replicated the top SNPs in a GWAS of melanoma risk from the MD Anderson Cancer Center (1804 cases and 1026 controls).ResultsA total of 3 SNPs with P value <0.001 were selected for in silico replication. One SNP was replicated: rs3902093 [A] in EXO1 promoter region (P_discovery = 6.6 × 10^?4, P_replication = 0.039, P_joint = 2.5 × 10^?4; OR_joint = 0.80, 95% CI: 0.71, 0.90). This SNP was associated with the expression of the EXO1; carriers of the A allele showed lower expression (P = 0.002).ConclusionOur study found that a promoter region SNP in the editing and processing nucleases gene EXO1 was associated with decreased expression of EXO1 and decreased melanoma risk. Further studies are warranted to validate this association and to investigate the potential mechanisms.