An aqueous Commiphora myrrha extract ameliorates paclitaxel-induced peripheral neuropathic pain in mice.

Background: Chemotherapy-induced neuropathic pain (CINP) is a debilitating side effect in individuals undergoing cancer treatment. Treatment of CINP with the current available classes of drugs is limited and often yields unsatisfactory results. Finding therapeutic alternatives of plant origin could provide a new way for the management of CINP. Commiphora myrrha (CM) resin extract has been reported to have anti-inflammatory and analgesic activities, but the effect of CM on neuropathic pain is yet to be investigated in CINP. Objectives: The aim of this study was to investigate the antinociceptive effect of CM extract in a mouse model of paclitaxel-induced neuropathic pain (PINP). Methods: The effects of CM on thermal hyperalgesia and mechanical allodynia were assessed in female BALB/c mice with PINP using a hot plate and a plantar aesthesiometer, respectively. Motor coordination was evaluated using a rotarod apparatus. The involvement of transient receptor potential vanilloid channel 1 (TRPV1) in CM actions was investigated using a capsaicin (a TRPV1 agonist)-induced nociception test. The genetic expression of Trpv1, Nrf2, Sod2, and Hmox1 was assessed using real-time PCR, while protein expression of TRPV1, Iba-1, and CD11b was assessed using Wes™. Results: Administration of CM to mice with established PINP produced a dose-dependent reduction in thermal hyperalgesia. Prophylactic treatment of mice with CM prevented the development of paclitaxel-induced thermal hyperalgesia and mechanical allodynia. CM did not change the motor coordination of mice, as the reaction latency and the rotational velocity of animals pretreated with CM extract were similar to those of animals pretreated with vehicle. CM significantly decreased the number and duration of the flick responses following capsaicin injection into the dorsal surface of the hind paw of mice. The protein expression of TRPV1 was upregulated in the spinal cord of paclitaxel-treated animals compared to vehicle-only-treated control animals, while CM-treated animals had values similar to vehicle-only-treated control animals. The mRNA expression of Nrf2, a major antioxidant transcription factor, was upregulated in the paw skin of mice treated with CM compared to those treated with paclitaxel alone. Conclusion: These results indicate that CM may both treat established and prevent the development of paclitaxel-induced thermal hyperalgesia and mechanical allodynia without any impairment in the motor activity of mice. CM may mediate its action through the peripheral inhibition of TRPV1 channel activity, restoration of normal TRPV1 protein expression in the spinal cord, and elevation of cellular antioxidant defenses. CM has the potential to be used as a therapeutic alternative to treat CINP.

Litoribacterium kuwaitense gen. nov., sp. nov., isolated from a Kuwait tidal flat.

A Gram-stain-positive, strictly aerobic, spore-forming, rod-shaped and non-motile bacterium designated strain SIJ1T was obtained from tidal flat sediment collected from the northern shore of Kuwait Bay, northwest of the Arabian Gulf. Strain SIJ1T grew optimally at 30 °C and pH 7-8 in the presence of 6 % (w/v) NaCl. The cell-wall peptidoglycan was based on meso-diaminopimelic acid and an unsaturated menaquinone with seven isoprene units (MK-7) was the predominant respiratory quinone. It contained anteiso-C15 : 0, iso-C16 : 0 and iso-C15 : 0 as the major fatty acids and ribose as the major whole-cell sugar. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, unidentified phospholipid, an unidentified glycolipid, phosphoglycolipid and an unidentified lipid. Phylogenetic analysis based on 16S rRNA genes revealed that SIJ1T showed a distinct evolutionary lineage within the Firmicutes. The DNA G+C content was 43.1 mol% and the full genome analysis for strain SIJ1T showed that it had a genome size of 3 989 945 bp and contained 4085 predicted protein-encoding genes. The SIJ1T annotated genome showed more stress resistance encoding genes in comparison to its closely related strains. The amino acid identity and average nucleotide identity data for the whole genome proved that strain SIJ1T does indeed represent a novel genus. The strain was distinguishable from the phylogenetically related genera through differences in several phenotypic properties. On the basis of the phenotypic, phylogenetic and genetic data, strain SIJ1T represents a novel genus and species in the family Bacillaceae, for which the name Litoribacterium kuwaitense gen. nov., sp. nov. is proposed. The type strain is SIJ1T (=DSM 28862T=LMG 28316T).

Grimontia sedimenti sp. nov., isolated from benthic sediments near coral reefs south of Kuwait.

A Gram-stain-negative, rod and rod-curved shaped motile bacterium designated strain S25T was obtained from benthic sediment collected near the Kubbar Island coral reefs south of Kuwait. Phenotypic analysis revealed that strain S25T was slightly halophilic, mesophilic and facultative anaerobic, fermenting d-glucose, d-ribose, d-mannose, d-mannitol, maltose, fructose, gentiobiose, cellobiose, melibiose, trehalose and sucrose. It was positive for oxidase and indole production and negative for arginine dihydrolase and lysine and ornithine decarboxylases. It contained C16 : 1 ω7c/C16 : 1 ω6c (summed feature 3), C18 : 1 ω7c (summed feature 8) and C16 : 0 as the major fatty acids. Strain S25T grew optimally at 30 °C and pH 8 in the presence of 3 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA sequences revealed that strain S25T is related to species of the genus Grimontia, having 99.15 % similarity to 'Grimontia indica' AK16T, 99.08 % to Grimontia celer 96-237T and 98.66 % to Grimontia marina IMCC 5001T. The DNA G+C content was 48.8 mol% and the full genome analysis for the strain S25T showed that the bacterium has a genome size of 5 158 621 bp and contains 4730 predicted protein-encoding genes. The average nucleotide identity values between the S25T genome and the genomes of its nearest matches ranged between 81.39 and 94.16 %. The strain was distinguishable from the phylogenetically related genera through differences in several phenotypic properties. On the basis of the phenotypic, phylogenetic and genetic data, strain S25T represents a novel species in the genus Grimontia, for which the name Grimontia sedimenti sp. nov. is proposed. The type strain of Grimontia sedimenti is S25T (=DSM 28878T=LMG 28315T).

Phage and Nucleocytoplasmic Large Viral Sequences Dominate Coral Viromes from the Arabian Gulf.

Corals that naturally thrive under extreme conditions are gaining increasing attention due to their importance as living models to understand the impact of global warming on world corals. Here, we present the first metagenomic study of viral communities in corals thriving in a thermally variable water body in which the temperature fluctuates between 11 and 39°C in different seasons. The viral assemblages of two of the most abundant massive (Porites harrisoni) and branching (Acropora downingi) corals in offshore and inshore reef systems in the northern Arabian Gulf were investigated. Samples were collected from five reef systems during summer, autumn and winter of 2011/2012. The two coral viromes contain 12 viral families, including 10 dsDNA viral families [Siphoviridae, Podoviridae, Myoviridae, Phycodnaviridae, Baculoviridae, Herpesviridae, Adenoviridae, Alloherpesviridae, Mimiviridae and one unclassified family], one-ssDNA viral family (Microviridae) and one RNA viral family (Retroviridae). Overall, sequences significantly similar to Podoviridae were the most abundant in the P. harrisoni and A. downingi viromes. Various morphological types of virus-like particles (VLPs) were confirmed in the healthy coral tissue by transmission electron microscopy, including large tailless VLPs and electron-dense core VLPs. Tailed bacteriophages were isolated from coral tissue using a plaque assay. Higher functional gene diversity was recorded in A. downingi than in P. harrisoni, and comparative metagenomics revealed that the Gulf viral assemblages are functionally distinct from Pacific Ocean coral viral communities.