Antimicrobial and Antibiofilm Activity of Lys-[Trp6]hy-a1 Combined with Ciprofloxacin Against Gram-Negative Bacteria.

BACKGROUND: Ciprofloxacin (Cip) is the most commonly used quinolone in clinical practice; however large-scale use has favored the increase of multiresistant pathogenic microorganisms. Antimicrobial peptides (AMPs) appear to be a promising alternative in potentiating these conventional drugs. OBJECTIVE: The aim of this study was to evaluate the effect of the peptide Lys-[Trp6]hy-a1 (lys-a1) on the antimicrobial and antibiofilm activity of ciprofloxacin against clinically relevant gram-negative bacteria. METHODS: The antimicrobial effects of Cip and lys-a1 were assessed by determining the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs). The synergistic action of Cip and lys-a1 was determined by checkerboard assay. The time-kill curve was constructed for the Cip/lys-a1 combination against Pseudomonas aeruginosa ATCC 9027. The antibiofilm activity of this combination was analyzed by crystal violet, colony-forming unit count and atomic force microscopy (AFM). RESULTS: The data demonstrated that lys-a1 was able to inhibit planktonic growth of strains of P. aeruginosa and Klebsiella pneumoniae both at 125 µg/mL. The fractional inhibitory concentration index (FICi) showed a synergistic effect between Cip and lys-a1 against P. aeruginosa, decreasing the MICs of the individual antimicrobial agents by 4- and 8-fold, respectively. This effect was also observed for the death kinetics and antibiofilm activity. Analysis of the early biofilms (6 h) as well as isolated cells by AFM images evidenced the cell perturbation caused by Cip/lys-a1 treatment. CONCLUSION: These data suggest that lys-a1 has biotechnological potential as a therapeutic tool for the treatment of infections caused by clinically relevant microorganisms, especially P. aeruginosa.

Evaluation of the proteomic profiles of ejaculated spermatozoa from Saanen bucks ( Capra hircus ).

The Saanen goat breed has been widely explored in breeding programmes; however, there are few reports about the breed's genetic and molecular composition. Thus, this study aimed to characterize the proteomic profile of spermatozoa from Saanen breeding goats. Five breeding animals with proven fertility were selected, the spermatozoa were collected, and the protein was extracted. Subsequently, the proteins were separated and analysed by two-dimensional electrophoresis and mass spectrometry; the proteins were then identified with the SwissProt database. A total of 31 proteins involved in reproduction were identified, including binding proteins on spermatozoa for fusion with the egg, acrosomal membrane proteins, metabolic enzymes, heat shock proteins, cytoskeletal proteins and spermatozoa motility proteins. The characterization of such proteins clarifies the molecular mechanisms of spermatogenesis and the modifications that ensure the success of fertilization.

Heme oxygenase-1/biliverdin/carbon monoxide pathway downregulates hypernociception in rats by a mechanism dependent on cGMP/ATP-sensitive K+ channels.

OBJECTIVE AND DESIGN: To investigate the role of heme oxygenase-1 (HO-1), carbon monoxide (CO), and biliverdin (BVD) in the zymosan-induced TMJ arthritis in rats. MATERIALS AND METHODS: Mechanical threshold was assessed before and 4 h after TMJ arthritis induction in rats. Cell influx, myeloperoxidase activity, and histological changes were measured in the TMJ lavages and tissues. Trigeminal ganglion and periarticular tissues were used for HO-1, TNF-α, and IL-1ß mRNA time course expression and immunohistochemical analyses. Hemin (0.1, 0.3, or 1 mg kg-1), DMDC (0.025, 0.25, or 2.5 µmol kg-1), biliverdin (1, 3, or 10 mg kg-1), or ZnPP-IX (1, 3 or 9 mg kg-1) were injected (s.c.) 60 min before zymosan. ODQ (12.5 µmol kg-1; s.c.) or glibenclamide (10 mg kg-1; i.p.) was administered 1 h and 30 min prior to DMDC (2.5 µmol kg-1; s.c), respectively. RESULTS: Hemin (1 mg kg-1), DMDC (2.5 µmol kg-1), and BVD (10 mg kg-1) reduced hypernociception and leukocyte migration, which ZnPP (3 mg kg-1) enhanced. The effects of DMDC were counteracted by ODQ and glibenclamide. The HO-1, TNF-α, and IL-1ß mRNA expression and immunolabelling increased. CONCLUSIONS: HO-1/BVD/CO pathway activation provides anti-nociceptive and anti-inflammatory effects on the zymosan-induced TMJ hypernociception in rats.

Strontium Ranelate Elevates Expression of Heme Oxygenase-1 and Decreases Alveolar Bone Loss in Rats.

OBJECTIVES: The purpose of this study was to determine the effects of strontium ranelate on ligature-induced periodontitis in rats and assess the putative involvement of heme oxygenase-1 (HO-1) pathway in these effects. MATERIAL AND METHODS: Male Wistar rats underwent nylon ligature placement around maxillary molars and were treated (v.o.) with strontium ranelate (20 or 100 mg/kg) for 7 days. After that, rats were euthanized and histomorphometric/histopathological analyses and RT-PCR for HO-1 expression were performed. RESULTS: Strontium ranelate (20 or 100 mg/kg) prevented bone resorption by 28% and 38%, respectively. Strontium ranelate treatment (100 mg/kg) up-regulated (P < 0.05) heme oxygenase-1 mRNA levels in the gingival tissues in comparison to control groups. CONCLUSIONS: Strontium ranelate prevented periodontal bone loss in experimental periodontitis in rats while heme oxygenase-1 mRNA levels increased after treatment.

Diversity of ejaculated sperm proteins in Moxotó bucks (Capra hircus ) evaluated by multiple extraction methods.

This study aimed to develop protocols for the extraction of sperm proteins from Moxotó goats (Capra hircus) and to compare the resulting proteomic maps. The sperm proteins were isolated using an extraction buffer containing 7 M urea and 2 M thiourea, 20 mM DTT, and one of the following detergents: 1% or 4% CHAPS; 1% or 4% SDS; 1% or 4% Triton X-100; or a combination of CHAPS and SDS. The 1-DE and 2-DE profiles of the isolated proteins revealed that the various isolation methods were efficient. Qualitative and quantitative differences in the 1-DE and 2-DE profiles were observed. 2-DE maps indicated that the amount and diversity of proteins visualized depended on the detergent that was used. Furthermore, this work revealed that the combination of detergents increased the resolution of some spots and retained the characteristics of the individual detergents, depending on their concentrations.

Neuroprotective Effects of Sulphated Agaran from Marine Alga Gracilaria cornea in Rat 6-Hydroxydopamine Parkinson's Disease Model: Behavioural, Neurochemical and Transcriptional Alterations.

Parkinson's disease (PD) is a multifactorial disease associated with the degeneration of dopaminergic neurons and behavioural alterations. Natural bioactive compounds may provide new therapeutic alternatives for neurodegenerative disorders, such as PD. The sulphated polysaccharides isolated from marine algae are heterogenic molecules that show different biological activities. The red marine alga Gracilaria cornea has a sulphated polysaccharide (SA-Gc) with structure and anti-inflammatory and antinociceptive activities reported in the literature. Therefore, this study aimed to evaluate the neuroprotective effects of SA-Gc in rat model PD induced by 6-hydroxydopamine (6-OHDA). Firstly, we established the PD model in rats, induced by an intrastriatal injection (int.) of 6-OHDA, followed by a single administration of SA-Gc (15, 30 or 60 µg; int.). On the 14th day, behavioural tests were performed. After killing, brain areas were dissected and used for neurochemical and/or transcriptional analyses. The results showed that SA-Gc (60 µg, int.) promoted neuroprotective effects in vivo through reducing the oxidative/nitroactive stress and through alterations in the monoamine contents induced by 6-OHDA. Furthermore, SA-Gc modulated the transcription of neuroprotective and inflammatory genes, as well as returning behavioural activities and weight gain to normal conditions. Thus, this study reports the neuroprotective effects of SA-Gc against 6-OHDA in rats.

Mechanisms involved in the anti-inflammatory action of a polysulfated fraction from Gracilaria cornea in rats.

The anti-inflammatory mechanisms of the sulfated polysaccharidic fraction obtained from red marine alga Gracilaria cornea (Gc-FI) were investigated using a paw edema model induced in rats by different inflammatory agents (carrageenan, dextran, serotonin, bradykinin, compound 48/80 or L-arginine). Gc-FI at the doses of 3, 9 or 27 mg/kg, subcutaneously--s.c., significantly inhibited rat paw edema induced by carrageenan and dextran, as confirmed by myeloperoxidase and Evans' blue assessments, respectively. Gc-FI (9 mg/kg, s.c.) inhibited rat paw edema induced by histamine, compound 48/80 and L-arginine. Additionally, Gc-FI (9 mg/kg, s.c.) inhibited Cg-induced edema in animals with intact mast cells but did not inhibit that with degranulated mast cells by compound 48/80, revealing a protective role on mast cell membranes. Gc-FI down-regulated the IL-1ß, TNF-α and COX-2 mRNA and protein levels compared with those of the carrageenan group, based on qRT-PCR and immunohistochemistry analyses. After inhibition with ZnPP IX, a specific heme oxygenase-1 (HO-1) inhibitor, the anti-inflammatory effect of Gc-FI was not observed in Cg-induced paw edema, suggesting that the anti-inflammatory effect of Gc-FI is, in part, dependent on the integrity of the HO-1 pathway. Gc-FI can target a combination of multiple points involved in inflammatory phenomena.

Isoform characterisation, heterologous expression and functional analysis of two lectins from Vatairea macrocarpa.

VML is a lectin from Vatairea macrocarpa seeds that has various biological activities. Here, we describe three new lectin isoforms from V. macrocarpa identified through genomic DNA analysis. One of these isoforms has high similarity to VML, while another that has noteworthy differences. We have denoted the new isoforms as VML-2, VML-3 and VML-4. Recombinant VML (rVML) and VML-2 (rVML-2) were expressed in Escherichia coli and were anticipated to have similar biological activity compared to native VML. Recombinant lectins were produced using a synthetic gene strategy to improve the expression levels. We obtained two active recombinant lectin isoforms from V. macrocarpa, and there was no significant difference between their biological activities. The conservation between carbohydrate-binding sites of recombinant and native proteins was demonstrated by specific inhibition of hemagglutin activity by D-galactose and lactose. However, no inhibition was observed in the presence of glucose and mannose. Our data show that the recombinant lectins VML and VML-2 are active and capable of recognising D-galactose and lactose. Moreover, the absence of glycosylation does not interfere with their biological activity.

Time-dependent modulation of AMPA receptor phosphorylation and mRNA expression of NMDA receptors and glial glutamate transporters in the rat hippocampus and cerebral cortex in a pilocarpine model of epilepsy.

The pilocarpine model in rodents reproduces the main features of mesial temporal lobe epilepsy related to hippocampus sclerosis (MTLE-HS) in humans. It has been demonstrated in this model that the phosphorylation of the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor GluR1 subunit is increased 1 h after pilocarpine treatment. Moreover, alterations in the levels of glutamate transporters have been associated with chronic epilepsy in humans. Despite these studies, the profile of these changes has not yet been addressed. We analyzed the protein content and phosphorylation profile of the AMPA receptor GluR1 subunit by western blotting. We also used quantitative real-time polymerase chain reaction to analyze the expression of glial glutamate transporters and the N-methyl-D-aspartate receptor NR1 subunit in the hippocampus (Hip) and cerebral cortex (Ctx) at different time points after pilocarpine-induced status epilepticus (Pilo-SE) in male adult Wistar rats. Biochemical analysis was performed in the Hip and Ctx at 1, 3, 12 h (acute period), 5 days (latent period), and 50 days (chronic period) after Pilo-SE. Key findings include an increase in the phosphorylation of GluR1-Ser(845) in the Ctx and GluR1-Ser(831) in the Hip at different times during the acute period, and a decrease in the total content of the GluR1 subunit in the Ctx in the latent period. There was a down-regulation of the mRNA expression and protein levels of EAAT1 and EAAT2, and a decrease of the NR1 mRNA expression, in the Ctx during the latent period. Notably, during the chronic period, the EAAT2 mRNA expression and protein levels decreased while the NR1 mRNA levels increased in the Hip. Taken together, our findings suggest a time- and structure-dependent imbalance of glutamatergic transmission in response to Pilo-SE, which might be associated with either epileptogenesis or the seizure threshold in MTLE-HS.

Antimicrobial and antibiofilm action of Casbane Diterpene from Croton nepetaefolius against oral bacteria.

OBJECTIVE: The antibacterial activity of Casbane Diterpene (CD) was evaluated in vitro against Streptococcus oralis, S. mutans, S. salivarius, S. sobrinus, S. mitis and S. sanguinis. The viability of planktonic cells was analysed by susceptibility tests (MIC and MBC) and antibiofilm action was assayed. METHODS: The minimal inhibitory and bactericidal concentrations (MIC and MBC) of oral Streptococcus were evaluated through microdilution tests. To assay antibiofilm activity, biofilms were generated on 96-wells polystyrene plates under the presence of CD and quantified by a crystal violet technique and colonies forming units counting. RESULTS: The CD isolated from Croton nepetaefolius showed antimicrobial effect on planktonic forms and biofilms of oral pathogens, with MIC values of 62.5 µg/mL against Streptococcus oralis and values between 125 and 500 µg/mL against S. mutans, S. salivarius, S. sobrinus, S. mitis and S. sanguinis. CD showed an inhibitory effect on S. mutans biofilm formation at 250 µg/mL, and a decrease on viable cell of 94.28% compared to the normal biofilm growth. CONCLUSIONS: The compound CD can be considered as a promising molecule for the treatment against oral pathogens responsible for dental biofilm.

Buck (Capra hircus) genes encode new members of the spermadhesin family.

Spermadhesins are the major proteins of boar seminal plasma and form a group of polypeptides probably involved in reproduction. In previous work, a member of the spermadhesin family from buck seminal plasma, called BSFP, was characterized by mass spectrometry and N-terminal sequencing. The present study aimed to clone and characterize the BSFP gene and investigate its expression along the genital tract using real-time polymerase chain reaction (PCR). The cDNAs of the seminal vesicle, testis, epididymis, bulbourethral gland, and ductus deferens were prepared from a buck. Following 3'- and 5'-end amplifications using seminal vesicle cDNA, we cloned and sequenced four highly similar (97-98%) nucleotide sequences encoding spermadhesins, which were named Bodhesin-1(Bdh-1), Bdh-2, Bdh-3, and Bdh-4. All deduced amino acid sequences contained the CUB domain signature and were 49-52% similar to boar AWN. Among the four Bdh amino acid sequences, Bdh-2 was the most similar to the BSFP N-terminal fragment. By using real-time PCR, it was verified specific amplifications for all Bdh in the seminal vesicle, testis, epididymis, and bulbourethral gland, with the exception of Bdh-2 in epididymis. The amplicons had a melting temperature and size of approximately 78 degrees C and 130 bp, respectively. Bdh expression was higher in the seminal vesicle when compared to the other tissues. The present work confirms that goat is the fifth mammalian species, after pig, cattle, horse, and sheep, in which spermadhesin molecules are found. To the best of our knowledge, this is the first report on buck spermadhesin genes using molecular cloning and expression profile.

Seed protein variation among pepper (Capsicum sp.) genotypes revealed by MALDI-TOF analysis.

A method for seed proteome analysis using MALDI-TOF mass spectrometry is described. The data were used to estimate the genetic diversity degree among twelve genotypes of pepper (Capsicum). The resulting spectra were converted into a binary matrix consisting of 23 protein data sets, and genetic similarity values were calculated with the FreeTree software and Jaccard's coefficient of similarity. We have also been able to identify the presence of certain proteins in the extracts, by checking their masses on on-line databases.