(-)-α-Bisabolol reduces nociception and trigeminal central sensitisation in acute orofacial neuropathic pain induced by infraorbital nerve injury.

Neuropathic orofacial pain conditions represent a challenge to diagnose and treat. Natural substances are promising therapeutic options for the control of pain. AIMS: This study aimed to examine whether (-)-α-bisabolol (BISA), a natural terpene, can attenuate nociceptive behaviour and central sensitisation in a rodent model of trigeminal neuropathic pain. MATERIALS AND METHODS: Infraorbital nerve transection (IONX) or sham operation was performed in adult male rats. Head withdrawal thresholds as a measure of facial mechanical sensitivity were tested with von Frey monofilaments applied bilaterally to the facial vibrissal pad pre-operatively (baseline) and then post-operatively before and at 60, 120, 240 and 360 min after administration of vehicle control per oris (p.o.) or BISA (200 mg/kg p.o.) (n = 8/group). Effects of BISA or vehicle on the activity of nociceptive neurons recorded in the medullary dorsal horn (MDH) were tested on post - operative day 8-10. ANOVA followed by post-hoc Bonferroni tested for statistically significant differences (p < 0.05) across study groups and time points. KEY FINDINGS: IONX animals (but not sham or naïve animals) showed post-operative facial mechanical hypersensitivity that was unaffected by vehicle. However, administration of BISA at post-operative day 7 significantly reversed the mechanical hypersensitivity in IONX rats; this effect lasted for at least 6 h. BISA also attenuated IONX-induced central sensitisation of MDH nociceptive neurons, as reflected in reversal of their reduced activation thresholds, increased responses to graded mechanical stimuli and enhanced spontaneous activity. SIGNIFICANCE: BISA may attenuate nociceptive behaviour and central sensitisation in a rat model of acute trigeminal neuropathic pain.

Clinical efficacy of new α-bisabolol mouthwashes in postoperative complications of maxillofacial surgeries: a randomized, controlled, triple-blind clinical trial.

OBJECTIVES: The present study aimed to evaluate the efficacy of α-bisabolol (BISA)-based mouthwashes in the oral hygiene of patients submitted to oral and maxillofacial surgery. MATERIALS AND METHODS: A randomized, controlled, triple-blind clinical trial was conducted with 30 patients, undergoing oral and maxillofacial surgery. Three types of mouthwashes were developed, based at 0.12% chlorhexidine, 0.5% BISA, and 0.12% chlorhexidine + 0.5% BISA. The patients were evaluated in the preoperative and postoperative period, divided into three groups according to the mouthwash to be used. In the postoperative period, the oral hygiene quality of the patients was evaluated through the simplified oral hygiene index; the healing of the wounds was evaluated observing the presence of suture dehiscence and/or infection, and the pain was established using the Visual Analogue Scale. The antiseptic effect of the mouthwashes was evaluated in vitro. RESULTS: There were no differences in the efficacy of BISA-containing mouthwashes for oral hygiene, healing, and pain, compared to chlorhexidine based at 0.12%. There were no differences in the antiseptic activity of chlorhexidine and chlorhexidine + α-bisabolol-based mouthwashes. CONCLUSION: The results indicate that BISA-based mouthwashes have clinical efficacy, in the improvement of oral hygiene and wound healing, as well as in the reduction of postoperative pain. CLINICAL RELEVANCE: Considering that BISA has analgesic, antimicrobial, and anti-inflammatory properties, it is relevant to evaluate the efficacy of BISA-based mouthwashes in the oral hygiene of patients undergoing oral and maxillofacial surgery, seeking a better postoperative recovery.

Gastroprotective and anti-inflammatory activities integrated to chemical composition of Myracrodruon urundeuva Allemão - A conservationist proposal for the species.

ETHNOPHARMACOLOGICAL RELEVANCE: Myracrodruon urundeuva Allemão (Aroeira-do-Sertão), Anacardiaceae, is one of the most used plants in folk medicine in Northeastern Brazil as an anti-inflammatory, healing and antiulcer. This species is threatened with extinction due to anthropogenic exploitation. The importance of this study is to demonstrate the feasibility of a conservationist model of replacement of the M. urundeuva adult tree (inner bark) for its under developing plants (shoots) in order to ensure the preservation of this species, but also to ensure sufficient raw material for pharmaceutical purposes. AIM OF THE STUDY: To characterize chemically and assess the gastroprotective and anti-inflammatory activities of the fluid extracts from M. urundeuva innebark (adult plant) as well as stem and leaves of shoots (young plant). MATERIALS AND METHODS: The fluid extracts were prepared by maceration-percolation with hydroalcoholic solution according to the methodology described in the Brazilian Pharmacopoeia. These extracts were cleaned-up through solid phase extraction (SPE) and chemically characterized by ultra-performance liquid chromatography coupled to mass spectrometry (UPLC-ESI-QTOF MS/MS). Gastroprotective and anti-inflammatory activities of the extracts (700 or 1000 mg/kg) were assessed on ethanol-induced gastric lesions and Croton oil-induced ear edema in rats, respectively. The extracts were evaluated for cytotoxicity in vitro. RESULTS: The UPLC-ESI-QTOF-MS/MS analysis evidenced the presence of chalcones, flavonoids and tannins. Gastroprotective and anti-inflammatory activities achieved with fluid extracts from the stems and leaves was similar to inner bark. The fluid extracts were not toxic. CONCLUSION: It is possible to replace the inner bark of the adult tree for the stems and leaves from the shoots as raw material to be used in the preparation of its the phytotherapeutics. Therefore, this finding may help in the implementation of public policies that ensure the conservation of the species along with its sustainable use for pharmaceutical purposes.

Human dirofilariasis in the eyelid caused by Dirofilaria repens: An imported case. / Dirofilariasis palpebral causada por Dirofilaria repens: un caso importado.

CLINICAL CASE: The case concerns a 33-year-old Ukrainian woman, who came to the Ophthalmology Emergency Service, stating that she had a «worm¼ under the skin of her upper left eyelid that wriggled at night and bit her. A complete examination revealed a subcutaneous foreign body, which showed a filarial appearance and seemed to crawl under the skin. It was surgically removed to discover a live parasite, PCR-identified as Dirofilaria repens. DISCUSSION: Humans are accidental hosts in the cycle of Dirofilaria. There are only 8 reported cases of subcutaneous infection in Spain. Due to global warming, D. repens has become an emerging infectious agent in Central Europe countries such as Ukraine. The findings in this case are discussed.

Silencing synaptic communication between random interneurons during Drosophila larval locomotion.

Genetic manipulation of individual neurons provides a powerful approach toward understanding their contribution to stereotypic behaviors. We describe and evaluate a method for identifying candidate interneurons and associated neuropile compartments that mediate Drosophila larval locomotion. We created Drosophila larvae that express green fluorescent protein (GFP) and a shibire(ts1) (shi(ts1)) transgene (a temperature-sensitive neuronal silencer) in small numbers of randomly selected cholinergic neurons. These larvae were screened for aberrant behavior at an elevated temperature (31-32°C). Among larvae with abnormal locomotion or sensory-motor responses, some had very small numbers of GFP-labeled temperature-sensitive interneurons. Labeled ascending interneurons projecting from the abdominal ganglia to specific brain neuropile compartments emerged as candidates for mediation of larval locomotion. Random targeting of small sets of neurons for functional evaluation, together with anatomical mapping of their processes, provides a tool for identifying the regions of the central nervous system that are required for normal locomotion. We discuss the limitations and advantages of this approach to discovery of interneurons that regulate motor behavior.

Bisabolol-induced gastroprotection against acute gastric lesions: role of prostaglandins, nitric oxide, and KATP+ channels.

The effects of Matricaria recutita and alpha-bisabolol, a bioactive component from Chamomile species, were investigated against gastric damage induced by absolute ethanol (96%, 1 mL per animal) in rats. The effects of M. recutita extract and alpha-bisabolol on gastric mucosal damage were assessed by determination of changes in mean gastric lesion area. Mechanistic studies were carried out at with 100 mg=kg alpha-bisabolol. We further examined the possible participation of prostaglandins, nitric oxide, and KATP+ channels in its mechanism. M. recutita reduced gastric damage in all doses tested. Alpha-bisabolol at oral doses of 50 and 100 mg=kg markedly attenuated the gastric lesions induced by ethanol to the extent of 87% and 96%, respectively. Pretreatments with the nitric oxide antagonist N-nitro-l-arginine methyl ester (10 mg=kg, i.p.) or with indomethacin, an inhibitor of cyclooxygenase, failed to block effectively the gastroprotective effect of alpha-bisabolol. Furthermore, the alpha-bisabolol effect was significantly reduced in rats pretreated with glibenclamide, an inhibitor of KATP+ channel activation. Thus we provide evidence that alpha-bisabolol reduces the gastric damage induced by ethanol, at least in part, by the mechanism of activation of KATP+ channels.

Relaxant effects of an alkaloid-rich fraction from Aspidosperma ulei root bark on isolated rabbit corpus cavernosum.

We described earlier that an alkaloid-rich fraction (F(3-5)) from Aspidosperma ulei (Markgr) induces penile erection-like behavioral responses in mice. This study verified a possible relaxant effect of this fraction on isolated rabbit corpus cavernosum (RbCC) strips precontracted by phenylephrine (1 microM) or K+ 60 mM. F(3-5) (1-300 microg ml(-1)) relaxed the RbCC strips in a concentration-dependent and reversible manner. The relaxant effect of F(3-5) (100 microg ml(-1)) on phenylephrine contraction was unaffected in the presence of atropine, N-omega-nitro-L-arginine methyl ester or 1H-[1,2,4]oxadiazole[4,3-a] quinoxalin-1-one and by preincubation with tetrodotoxin, glibenclamide, apamine and charybdotoxin suggesting that mechanisms other than cholinergic, nitrergic, sGC activation or potassium channel opening are probably involved. However, the phasic component of the contraction induced by K+ 60 mM as well as the maximal contraction elicited by increasing external Ca2+ concentrations in depolarized corpora cavernosa was inhibited by F(3-5). We conclude that F(3-5) relaxes the RbCC smooth muscle, at least in part, through a blockade of calcium influx or its function.

Acute effects of guarana (Paullinia cupana Mart.) on mouse behaviour in forced swimming and open field tests.

Guarana, a herbal extract from the seeds of Paullinia cupana Mart. has been evaluated in comparison with caffeine on mouse behaviour in forced swimming and open field tests. Guarana (25 and 50 mg/kg, p.o.) and caffeine (10 and 20 mg/kg, p.o.) each significantly reduced the duration of immobility in the forced swimming test suggesting an antidepressant-like effect in mice. At these doses, neither substance affected ambulation in the open field test. However, a high dose of guarana (100 mg/kg) and caffeine (30 mg/kg) significantly enhanced the locomotor activity in the open field test. Caffeine, but not guarana, could effectively block an adenosine agonist, cyclopentyl adenosine (CPA)-induced increase in swimming immobility suggesting that mechanism(s) other than the adenosinergic mechanism are involved in the antidepressant-like activity of guarana.

Attenuation of ischemia/reperfusion-induced intestinal injury by oleo-resin from Copaifera langsdorffii in rats.

Copaifera langsdorffii oleo-resin (CLOR) is a reputed herbal medicine used to combat gastrointestinal functional disorders. Our previous studies show that CLOR prevents gastric ulceration and promotes wound healing. This study examined the effects of CLOR on intestinal damage associated with mesenteric ischemia/reperfusion in rat. Wistar albino rats were divided into four groups of six in each. Group 1: Sham operated, Group 2: Vehicle + 45 min of ischemia followed by 60 min reperfusion (I/R), Groups 3 and 4: I/R + CLOR (200 and 400 mg /kg, p.o., respectively). All treatments were given 24 h, 12 h and 2 h before I/R. Animals were sacrificed at the end of reperfusion period and ileal tissue samples were obtained for biochemical analysis. Myeloperoxidase (MPO), an index of polymorphonuclear leukocytes; malondialdehyde (MDA), an end product of lipoperoxidation; catalase (CAT), an antioxidant enzyme; reduced glutathione (GSH), a key antioxidant; and nitrite, a marker of nitric oxide (NO) production were determined in ileum homogenates. The results show that I/R produces a significant increase in MDA content, MPO, and CAT activities with a significant decrease in GSH and an elevation in nitrite production, as compared to sham control. CLOR treatment caused significant attenuations in I/R-associated increases of MPO, MDA and CAT activities and on nitrite level. Besides, CLOR could effectively prevent the I/R-associated depletion of GSH. The data indicate that the oleo-resin has a protective action against I/R-induced intestinal tissue damage, which appeared to be, at least in part, due to an antioxidant and anti-lipid peroxidation mechanism.

1,8-cineole (eucalyptol), a monoterpene oxide attenuates the colonic damage in rats on acute TNBS-colitis.

The monoterpene oxide, 1,8-cineole (cineole, eucalyptol) was examined for its possible influence on the acute phase of trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats. The test compound, 1,8-cineole (200 and 400 mg/kg) or vehicle (1 ml, 2% Tween 80) was instilled rectally, 24, and 2 h before (pre-treatment) or 2 and 24 h after (post-treatment) the induction of colitis by intracolonic administration of TNBS (0.25 ml of 25 mg of TNBS in 50% ethanol). Rats were killed 48 h after colitis induction and colonic segments were analysed for gross damage scores, changes in wet weights, myeloperoxidase activity, an indicator of neutrophilic infiltration and glutathione level, a major cellular antioxidant. TNBS induced an extensive inflammation and ulceration in the colon. Colonic damage was associated with an increase in myeloperoxidase activity and by a decrease in glutathione. When compared to vehicle-treated TNBS controls, a marked reduction in gross damage scores and wet weights (mg/cm) of colonic segments were evident in animals pre-treated but not post-treated with 1,8-cineole. Cineole also significantly reduced the myeloperoxidase activity, and caused repletion of glutathione. These results confirm the anti-inflammatory action of 1,8-cineole and suggest its potential value as a dietary flavoring agent in the prevention of gastrointestinal inflammation and ulceration.

Guarana (Paullinia cupana Mart.) offers protection against gastric lesions induced by ethanol and indomethacin in rats.

The effects of guarana (Paullinia cupana) extract were analyzed in rats on acute gastric lesions induced by ethanol and indomethacin and were compared to those produced by caffeine, a methylxanthine. Guarana (50 and 100 mg/kg p.o.) pretreated animals showed a significant reduction in the severity of gastric lesions induced by absolute ethanol in a manner similar to caffeine (20 and 30 mg/kg p.o.). Against indomethacin-induced gastric ulceration, guarana at a higher dose offered significant protection but caffeine was ineffective at the doses tested. In 4 h pylorus-ligated rats, both guarana and caffeine caused significant diminution in the gastric secretory volume as well as the total acidity. Gastrointestinal transit in mice was not significantly affected by either of these agents. These findings indicate that guarana has a gastroprotective property that needs further elucidation as regards to its mechanism.

Ternatin, an anti-inflammatory flavonoid, inhibits thioglycolate-elicited rat peritoneal neutrophil accumulation and LPS-activated nitric oxide production in murine macrophages.

Ternatin, an anti-inflammatory flavonoid from Egletes viscosa Less., was examined for its possible influence on thioglycolate-elicited neutrophil influx into the rat peritoneal cavity in vivo and nitric oxide production in lipopolysaccharide (LPS)-activated mouse peritoneal macrophages ex vivo. The neutrophil influx induced by thioglycolate was found to be significantly lower in ternatin (25 and 50 mg/kg, s. c.) pre-treated rats with a similar magnitude of inhibition produced by dexamethasone (1 mg/kg, s. c.), a known anti-inflammatory agent. Also, peritoneal macrophages from ternatin (25 mg/kg)-treated mice that were exposed to LPS demonstrated significantly less production of nitric oxide (NO). These results suggest that ternatin exerts its anti-inflammatory action, at least in part, through inhibition of neutrophil migration and modulation of macrophage function.

Cloning, genomic organization and expression pattern of a novel Drosophila gene, the disco-interacting protein 2 (dip2), and its murine homolog.

We report the cloning and initial characterization of a novel gene encoding the Disco interacting protein 2 (Dip2). dip2 DNA complementary to RNA (cDNA) showed a high degree of sequence similarity to cDNAs of unknown function previously identified in humans and Caenorhabditis elegans. We have cloned the mouse homolog of the dip2 cDNA and characterized the expression of this gene by Northern blotting analysis and in situ hybridization to whole mount embryos. Our observations demonstrate that there is a remarkable degree of sequence conservation at the dip2 locus that is reflected in the nervous system-specific expression of both the Drosophila and mouse homologs.

Investigations on the antinociceptive activity of crude extracts from Croton cajucara leaves in mice.

The crude leaf extracts of Croton cajucara Benth. were studied for their antinociceptive property in chemical and thermal models of nociception in mice. All the tested extracts (hexanic, chloroformic and methanolic), at oral doses of 100 and 200 mg/kg demonstrated significant inhibition of acetic acid-induced writhing and the second phase response of formalin, but did not manifest a significant effect in hot-plate test.

Drosophila Amphiphysin is a post-synaptic protein required for normal locomotion but not endocytosis.

Clathrin-mediated endocytosis is required to recycle synaptic vesicles for fast and efficient neurotransmission. Amphiphysins are thought to be multiprotein adaptors that may contribute to this process by bringing together many of the proteins required for endocytosis. Their in vivo function, however, has yet to be determined. Here, we show that the Drosophila genome encodes a single amphiphysin gene that is broadly expressed during development. We also show that, unlike its vertebrate counterparts, Drosophila Amphiphysin is enriched postsynaptically at the larval neuromuscular junction. To determine the role of Drosophila Amphiphysin, we also generated null mutants which are viable but give rise to larvae and adults with pronounced locomotory defects. Surprisingly, the locomotory defects cannot be accounted for by alterations in the morphology or physiology of the neuromuscular junction. Moreover, using stimulus protocols designed to test endocytosis under moderate and extreme vesicle cycling, we could not detect any defect in the neuromuscular junction of the amphiphysin mutant. Taken together, our findings suggest that Amphiphysin is not required for viability, nor is it absolutely required for clathrin-mediated endocytosis. However, Drosophila Amphiphysin function is required in both larvae and adults for normal locomotion.

Behavioral characterization and genetic analysis of the Drosophila melanogaster larval response to light as revealed by a novel individual assay.

A new assay was designed, named checker, that measures the individual response to light in the fruitfly Drosophila melanogaster larva. In this assay the Drosophila larva apparently modulates its pattern of locomotion when faced with a choice between a dark and lit environment by orienting its movement towards the dark environment. We show that, in this assay, a response to light can be measured as an increase in residence time in the dark versus the lit quadrant. Mutations that disrupt phototransduction in the adult Drosophila abolish the larval response to light, demonstrating that this larval visual function is similar to that of the adult fly. Similarly, no response to light was detected in strains where the larval visual system (photoreceptors and target area) was disrupted by a mutation in the homeobox containing gene sine oculis (so) gene. Ablation of photoreceptors by the targeted expression of the cell death gene hid under the control of the photoreceptor-specific transcription factor glass (gl) abolishes this response entirely. Finally, we demonstrate that this response to light can be mediated by rhodopsins other than the blue absorbing Rh1.

The tamas gene, identified as a mutation that disrupts larval behavior in Drosophila melanogaster, codes for the mitochondrial DNA polymerase catalytic subunit (DNApol-gamma125).

From a screen of pupal lethal lines of Drosophila melanogaster we identified a mutant strain that displayed a reproducible reduction in the larval response to light. Moreover, this mutant strain showed defects in the development of the adult visual system and failure to undergo behavioral changes characteristic of the wandering stage. The foraging third instar larvae remained in the food substrate for a prolonged period and died at or just before pupariation. Using a new assay for individual larval photobehavior we determined that the lack of response to light in these mutants was due to a primary deficit in locomotion. The mutation responsible for these phenotypes was mapped to the lethal complementation group l(2)34Dc, which we renamed tamas (translated from Sanskrit as "dark inertia"). Sequencing of mutant alleles demonstrated that tamas codes for the mitochondrial DNA polymerase catalytic subunit (DNApol-gamma125).

Antioestrogenic effect of trans-dehydrocrotonin, a nor-clerodane diterpene from Croton cajucara Benth. in rats.

This study examined trans-dehydrocrotonin (t-DCTN), a nor-clerodane diterpene isolated from the Brazilian medicinal plant Croton cajucara Benth., for a possible antioestrogenic activity using immature rats as a model system for bioassay of oestrogen, and for an antiimplantation effect in regularly cycling rats of proven fertility. In the antioestrogen test, t-DCTN (25 and 50 mg/kg) effectively prevented oestrogen-induced increases of uterine wet weights. In addition, the vaginal openings provoked by oestrogen were completely prevented by t-DCTN. However, blastocyst-implantation was only insignificantly affected in t-DCTN pretreated animals. These results suggest that t-DCTN may be an antioestrogen and warrants further studies with regard to its mechanism of action.

Autoregulation of the Drosophila disconnected gene in the developing visual system.

The Drosophila disconnected (disco) gene is required for the formation of appropriate connections between the larval optic nerve and its target cells in the brain. The disco gene encodes a nuclear protein with two zinc fingers, which suggests that the gene product is a transcription factor. Here, we present data supporting this notion. We find that disco expression in the optic lobe primordium, a group of cells contacted by the developing optic nerve, depends on an autoregulatory feedback loop. We show that wild-type disco function is required for maintenance of disco mRNA and protein expression in the developing optic lobe. In addition, we demonstrate that ubiquitous Disco activity supplied by a heat-inducible gene construct activates expression from the endogenous disco gene specifically in the optic lobe primordium. Consistent with a role of Disco as a transcriptional regulatory protein, we show that portions of the Disco protein are capable of activating the transcription of reporter constructs in a heterologous system. Moreover, we find that the zinc finger portion of Disco binds in vitro to sequences located near the disco transcription unit, suggesting that Disco autoregulates its transcription in the optic lobe primordium by direct binding to a regulatory element in its own promoter.

Effects of acute and repeated dose administration of caffeine and pentoxifylline on diazepam-induced mouse behavior in the hole-board test.

RATIONALE: The behavioral effects of methyl xanthines and their interactions with benzodiazepines have not been clearly established in animal models of anxiety. OBJECTIVE: The present study extended the previous studies to determine the effects of acute and repeated administration of caffeine, a non-specific phosphodiesterase (PDE) inhibitor and pentoxyfylline, a specific type-4 phosphodiesterase (PDE4) inhibitor on (1) baseline anxiety-like behavior and (2) the response to an acute challenge with diazepam on anxiety-like behavior in the hole-board test. METHODS: Mice were observed for the number of head-dips they made into the holes of the hole-board apparatus during a 5-min period, starting 30 min after acute (20 mg/kg) and repeated oral dose (20 mg/kg, twice a day for 4 days) administration of caffeine and pentoxifylline. In separate experiments, the response to an acute challenge with graded doses of diazepam (0.375 3 mg/kg, SC) was observed in naive mice or mice on acute and repeated dose regimen with methyl xanthines. RESULTS: Mice on acute but not after repeated dose regimen demonstrated a significantly increased number of hole-dips, indicating an anxiolytic-like effect of methylxanthines. Diazepam at the lower doses (0.375 and 0.75 mg/kg) but not at the highest doses (1.5 and 3 mg/kg) examined produced a significant anxiolytic-like effect. After an acute dose exposure of mice to caffeine and pentoxifylline, a rightward shift in the dose-response curve of diazepam was observed and particularly at 1.5 mg/kg dose, the net effect of diazepam was significantly enhanced which was, however, impaired upon repeated administration, more so with caffeine than with pentoxifylline. CONCLUSIONS: It is concluded that the xanthine drugs exert anxiolytic-like activity similar to diazepam in the hole-board test. In addition, they seem to modulate the anxiolytic effects of diazepam after both acute and repeated administration, probably as a result of an endogenous adenosinergic mechanism which may have therapeutic significance.