7 research outputs found

    Data on the Lignosus rhinocerotis water soluble sclerotial extract affecting intracellular calcium level in rat dorsal root ganglion cells

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    The data in this article contain supporting evidence for the research manuscript entitled ā€œBronchodilator effects of Lignosus rhinocerotis extract on rat isolated airways is linked to the blockage of calcium entryā€ by Lee et al. (2018) [1]. The data were obtained by calcium imaging technique with fluorescent calcium indicator dyes, Fura 2-AM, to visualize calcium ion movement in the rat dorsal ganglion (DRG) cells. The effects of L. rhinocerotis cold water extract (CWE1) on intracellular calcium levels in the DRG cells were presented. Keywords: Lignosus rhinocerotis, Medicinal mushroom, Bronchodilators, Calcium dynamic

    Anti-nociceptive and desensitizing effects of olvanil on capsaicin-induced thermal hyperalgesia in the rat

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    Background: Olvanil (NE 19550) is a non-pungent synthetic analogue of capsaicin, the natural pungent ingredient of capsicum which activates the transient receptor potential vanilloid type-1 (TRPV1) channel and was developed as a potential analgesic compound. Olvanil has potent anti-hyperalgesic effects in several experimental models of chronic pain. Here we report the inhibitory effects of olvanil on nociceptive processing using cultured dorsal root ganglion (DRG) neurons and compare the effects of capsaicin and olvanil on thermal nociceptive processing in vivo; potential contributions of the cannabinoid CB1 receptor to olvanilā€™s anti-hyperalgesic effects were also investigated.Methods: A hot plate analgesia meter was used to evaluate the anti-nociceptive effects of olvanil on capsaicin-induced thermal hyperalgesia and the role played by CB1 receptors in mediating these effects. Single cell calcium imaging studies of DRG neurons were employed to determine the desensitizing effects of olvanil on capsaicin-evoked calcium responses. Statistical analysis used Studentā€™s t test or one way ANOVA followed by Dunnettā€™s post-hoctest as appropriate.Results: Both olvanil (100 nM) and capsaicin (100 nM) produced significant increases in intracellular calcium concentrations [Ca2+]I in cultured DRG neurons. Olvanil was able to des ensitise TRPV1 responses to further capsaicin exposure more effectively than capsaicin. Intra plantar injection of capsaicin (0.1, 0.3 and 1Ī¼g) produced a robust TRPV1-dependant thermal hyperalgesia in rats, whilst olvanil (0.1, 0.3 and 1Ī¼g) produced no hyperalgesia, emphasizing its lack of pungency. The highest dose of olvanil significantly reduced the hyperalgesic effects of capsaicin in vivo. Intraplantar injection of the selective cannabinoid CB1 receptor antagonist rimonabant (1Ī¼g) altered neither capsaicin-induced thermal hyperalgesia nor the desensitizing properties of olvanil, indicating a lack of involvement of CB1receptors.Conclusions: Olvanil is effective in reducing capsaicin-induced thermal hyperalgesia, probably via directly desensitizingTRPV1 channels in a CB 1 receptor-independent fashion. The results presented clearly support the potential for olvanil in the development of new topical analgesic preparations for treating chronic pain conditions while avoiding the unwanted side effects of capsaicin treatments

    Post-stroke infection: A systematic review and meta-analysis

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    <p>Abstract</p> <p>Background</p> <p><b>s</b>troke is the main cause of disability in high-income countries, and ranks second as a cause of death worldwide. Patients with acute stroke are at risk for infections, but reported post-stroke infection rates vary considerably. We performed a systematic review and meta-analysis to estimate the pooled post-stroke infection rate and its effect on outcome.</p> <p>Methods</p> <p>MEDLINE and EMBASE were searched for studies on post-stroke infection. Cohort studies and randomized clinical trials were included when post-stroke infection rate was reported. Rates of infection were pooled after assessment of heterogeneity. Associations between population- and study characteristics and infection rates were quantified. Finally, we reviewed the association between infection and outcome.</p> <p>Results</p> <p>87 studies were included involving 137817 patients. 8 studies were restricted to patients admitted on the intensive care unit (ICU). There was significant heterogeneity between studies (P < 0.001, I<sup>2 </sup>= 97%). The overall pooled infection rate was 30% (24-36%); rates of pneumonia and urinary tract infection were 10% (95% confidence interval [CI] 9-10%) and 10% (95%CI 9-12%). For ICU studies, these rates were substantially higher with 45% (95% CI 38-52%), 28% (95%CI 18-38%) and 20% (95%CI 0-40%). Rates of pneumonia were higher in studies that specifically evaluated infections and in consecutive studies. Studies including older patients or more females reported higher rates of urinary tract infection. Pneumonia was significantly associated with death (odds ratio 3.62 (95%CI 2.80-4.68).</p> <p>Conclusions</p> <p>Infection complicated acute stroke in 30% of patients. Rates of pneumonia and urinary tract infection after stroke were 10%. Pneumonia was associated with death. Our study stresses the need to prevent infections in patients with stroke.</p

    Noladin ether, a putative endocannabinoid, attenuates sensory neurotransmission in the rat isolated mesenteric arterial bed via a non-CB(1)/CB(2) G(i/o) linked receptor

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    1. Noladin ether has recently been reported to be an endocannabinoid, with selectivity for the cannabinoid (CB) CB(1) receptor. In the present study, we investigated the effects of noladin ether in the rat isolated mesenteric arterial bed, cultured dorsal root ganglia (DRG) cells and human vanilloid (TRPV1)-receptor-expressing HEK293 cells (TRPV1-HEK293 cells). 2. Electrical field stimulation of the mesenteric bed evoked frequency-dependent vasorelaxation due to the action of calcitonin gene-related peptide (CGRP) released from sensory nerves. Noladin ether (0.1ā€“3 Ī¼M) attenuated sensory neurogenic relaxation in a concentration-dependent manner. Noladin ether (1 Ī¼M) reduced vasorelaxation at a submaximal frequency (8 Hz), from 57.3Ā±6.8 to 23.3Ā±3.8% (P<0.05, n=4). 3. The inhibitory effects of noladin ether were unaffected by the CB(1) antagonists SR141716A and LY320135, and the CB(2) antagonist SR144528 (1 Ī¼M). 4. Noladin ether had no effect on vasorelaxation elicited by exogenous CGRP or capsaicin. These data suggest that noladin ether is acting at a prejunctional site and no interaction with TRPV1 is involved. 5. In mesenteric beds from pertussis toxin (PTX)-pretreated rats, the inhibitory actions of noladin ether on sensory neurotransmission were abolished, indicating the involvement of G(i/o) protein-coupled receptors. 6. Noladin ether evoked a concentration-dependent increase in intracellular Ca(2+) concentration in TRPV1-HEK293 cells at 10 Ī¼M (36.5Ā±3.2% of maximal capsaicin-induced response), but it was a less potent agonist than both capsaicin and anandamide and at 1 Ī¼M it was essentially inactive. Noladin ether (1 Ī¼M) had no effect on capsaicin-evoked Ca(2+) responses in DRG cells, and produced no response alone, indicating it neither modulates nor acts directly on TRPV1 receptors. 7. These data demonstrate that noladin ether attenuates sensory neurotransmission in rat mesenteric arteries via a non-CB(1) non-CB(2) PTX-sensitive prejunctional site, independently of TRPV1 receptors

    The Peptide PnPP-19, a Spider Toxin Derivative, Activates Ī¼-Opioid Receptors and Modulates Calcium Channels

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    The synthetic peptide PnPP-19 comprehends 19 amino acid residues and it represents part of the primary structure of the toxin Ī“-CNTX-Pn1c (PnTx2-6), isolated from the venom of the spider Phoneutria nigriventer. Behavioural tests suggest that PnPP-19 induces antinociception by activation of CB1, Ī¼ and Ī“ opioid receptors. Since the peripheral and central antinociception induced by PnPP-19 involves opioid activation, the aim of this work was to identify whether this synthetic peptide could directly activate opioid receptors and investigate the subtype selectivity for Ī¼-, Ī“- and/or Īŗ-opioid receptors. Furthermore, we also studied the modulation of calcium influx driven by PnPP-19 in dorsal root ganglion neurons, and analyzed whether this modulation was opioid-mediated. PnPP-19 selectively activates Ī¼-opioid receptors inducing indirectly inhibition of calcium channels and hereby impairing calcium influx in dorsal root ganglion (DRG) neurons. Interestingly, notwithstanding the activation of opioid receptors, PnPP-19 does not induce Ī²-arrestin2 recruitment. PnPP-19 is the first spider toxin derivative that, among opioid receptors, selectively activates Ī¼-opioid receptors. The lack of Ī²-arrestin2 recruitment highlights its potential for the design of new improved opioid agonists
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