Antidiarrheal activity of α-terpineol in mice dos Santos Negreiros, Polyanna; da Costa, Douglas Soares; da Silva, Valdelânia Gomes ...
Biomedicine & pharmacotherapy,
February 2019, 2019-Feb, 2019-02-00, 20190201, 2019-02-01, Letnik:
110
Journal Article
Recenzirano
Odprti dostop
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Diarrhea is one of the leading causes of infant death in the world accounting for high child mortality rate. It is also present in different pathophysiologies related to several ...etiological agents. The aim of this study is to investigate the antidiarrheal effect of α –Terpineol (α-TPN) in different diarrhea models in rodents. The antidiarrheal effect of α-TPN in the treatment of acute diarrhea and enteropooling induced by castor oil or PGE2 in Swiss mice pretreated orally with saline (NaCl 0.9%), Loperamide (5 mg/kg) and α-TPN (6.25, 12.5, 25 and 50 mg/kg) was analyzed. Additionally, parameters of severity, total weight of faeces and post-treatment for 4 h were evaluated. Modulation of the opioid and cholinergic pathways was performed and intestinal transit model using activated charcoal as marker was also used. The effect of α-TPN on secretory diarrhea was investigated using the model of fluid secretion in intestinal loops isolated from cholera toxin-treated mice. α-TPN showed antidiarrheal effect (*p < 0.05), reducing the total stool amount (*55%, *48%, *44%, *24%) and diarrheal (*47%, *66%; *56%, 10%) respectively for the doses tested. All doses investigated in the enteropooling test presented significant changes (*46%, *78%, *66%, *41% respectively) in relation to the control. α-TPN through the muscarinic pathway reduced the gastrointestinal transit (*31%), besides inhibiting PGE2-induced diarrhea (*39%). α-TPN also reduced fluid formation and loss of Cl− ions, by interacting directly with GM1 receptors and cholera toxin, thus increasing the uptake of intestinal fluids. The results suggest an anti-diarrheal activity of α-TPN due to its anticholinergic action, ability to block PGE2 and GM1 receptors and interaction with cholera toxin in secretory diarrhea, making it a promising candidate drug for the treatment of diarrheal diseases.
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The present study evaluated the role of heme oxygenase 1 (HO-1)/carbon monoxide (CO) pathway in the cholera toxin-induced diarrhea and its possible action mechanism. The ...pharmacological modulation with CORM-2 (a CO donor) or Hemin (a HO-1 inducer) decreased the intestinal fluid secretion and Cl− efflux, altered by cholera toxin. In contrast, ZnPP (a HO-1 inhibitor) reversed the antisecretory effect of Hemin and potentiated cholera toxin-induced intestinal secretion. Moreover, CORM-2 also prevented the alteration of intestinal epithelial architecture and local vascular permeability promoted by cholera toxin. The intestinal absorption was not altered by any of the pharmacological modulators. Cholera toxin inoculation also increased HO-1 immunoreactivity and bilirubin levels, a possible protective physiological response. Finally, using fluorometric technique, ELISA assay and molecular docking simulations, we show evidence that CO directly interacts with cholera toxin, forming a complex that affects its binding to GM1 receptor, which help explain the antisecretory effect. Thus, CO is an essential molecule for protection against choleric diarrhea and suggests its use as a possible therapeutic tool.
Diarrhea is a condition in which the individual has about three or more daily bowel movements, followed by changes in stool consistency. It is currently considered as one of the worst public health ...problems due to the number of cases and deaths involved and difficulty of treatment. Thus, the use of natural products is an alternative for new treatments. Among these possibilities is Farnesol (C15H26O), a sesquiterpene found in different herbal species that has known biological activities. The objective of this study was to evaluate the antidiarrheal activity of Farnesol (FOH). Initially, FOH activity was evaluated in models of diarrhea and enteropooling induced by castor oil and PGE2. To evaluate motility, the opioid and cholinergic pathways were studied. In addition, the effect of FOH was investigated in the secretion model in intestinal loops treated with cholera toxin. FOH was evaluated for the ability to absorb fluids in intestinal loops and interact with GM1 receptors using the ELISA method and molecular docking. The dose of 50 mg/kg of FOH showed the best results in all antidiarrheal activity tests with castor oil and PGE2, being considered as the standard dose, reducing motility by anticholinergic mechanisms. There was a reduction in fluid secretion when FOH interacted directly with GM1 receptors; cholera toxin and molecular docking showed strong interaction between farnesol and these targets. In view of the results presented, the antidiarrheal activity occurs through anticholinergic, anti-inflammatory and anti-secretory action, making farnesol a potential candidate for the development of a new drug to treat diarrheal diseases.
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The increase in urbanization and industrialization has contributed to the contamination of different environments by means of xenobiotic compounds, such as heavy metals, causing changes in microbial ...communities. Among these metals, the Mercury (Hg2+) is one the most prevalent toxic metals for the environment The present study aimed to evaluate the effect of mercury on the formation of biofilm by environmental (collected from urban stream water) and clinical isolates of Klebsiella pneumoniae. In addition, antibiotic resistance, virulence factors, and genetic diversity were investigated. Taxonomic identity of eight isolates (one reference, two clinical, and five environmental isolates) was performed by MALDI-TOF-MS, while the antibiotic susceptibility profile was assessed by the disc diffusion method. The ability to form biofilms was evaluated by culture on Congo red agar and by crystal violet staining. Biofilm structure was analyzed by scanning electron microscopy. The hydrophobicity profile and the presence of the virulence genes cps, fimH, and mrkD was investigated. The presence of merA and its relationship with antimicrobial resistance were also assessed. The identity of all isolates was confirmed by MALDI-TOF-MS, and different profiles of resistance to mercury and antibiotics as well as of biofilm formation were identified for the clinical and environmental isolates. All isolates were hydrophilic and positive for the virulence genes cps, fimH, and mrkD; only the clinical isolate K36-A2 was positive for merA. The diversity of the isolates was confirmed by ERIC-PCR, which revealed high heterogeneity among the isolates. In conclusion, the data demonstrate that the investigated isolates present different responses to exposure to Hg2+ and correspond to distinct populations of K. pneumoniae disseminated in the investigated environment. The data obtained in this work will aid in understanding the mechanisms of survival of this pathogen under adverse conditions.
•In vitro effect of Hg2+ was observed on the formation of biofilms in K. pneumoniae.•Hg2+ can act as a stress factor for most isolates of K. pneumoniae.•Different populations of K. pneumoniae were observed in the analyzed ecosystem.•The work discusses mechanisms of survival of this pathogen under adverse conditions.
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The water-soluble protein fraction obtained from Plumeria pudica (LPPp) latex has previously been demonstrated to have anti-inflammatory and antinociceptive effects. In the present ...study, LPPp was tested for activity against diarrhea induced by castor oil, prostaglandin E2 (PGE2) or cholera toxin. Different doses of LPPp (10, 20 or 40mg/kg) significantly inhibited the percentage of diarrheal stools (31.18%, 42.97% and 59.70%, respectively) induced by castor oil. This event was followed by significant reduction of both intestinal fluid accumulation (31.42%; LPPp 40mg/kg) and intestinal transit (68.4%; LPPp 40mg/kg). The pretreatment of animals with LPPp (40mg/kg) prevented glutathione and malondialdehyde alterations induced by castor oil. The effects of LPPp against diarrhea induced by castor oil were lost when the fraction was submitted to protein denaturing treatment with heat. LPPp (40mg/kg) also inhibited the average volume of intestinal fluid induced by PGE2 (inhibition of 46.0%). Furthermore, LPPp (40mg/kg) prevented intestinal fluid secretion accumulation (37.7%) and chloride ion concentration (50.2%) induced by cholera toxin. In parallel, colorimetric assays demonstrated that proteinases, chitinases and proteinase inhibitors were found in LPPp. Our data suggest that the antidiarrheal effect of LPPp is due to its protein content and is probably associated with its anti-inflammatory properties.
•A new peptide (1341g/mol) from Jatropha curcas seeds was isolated.•It is inserted in a putative conserved domain of late-embryogenesis proteins.•The circular but not the linear peptide increased the ...proteolytic activity of papain.
A new peptide (1341g/mol) from Jatropha curcas seeds was isolated. The linear sequence (APTLSGGSVPRDAD) was deduced by de novo peptide sequencing, and further used as scaffold for synthesis of linear (1342g/mol) and cyclic (1324g/mol) synthetic analogues. The full peptide sequence was identified as inserted in a putative conserved domain of late-embryogenesis proteins which produced a significant alignment hit (100% of identity and E-value of 1e−05) with a hypothetical protein JCGZ_12502 of J. curcas. Whereas in the linear peptide predominated the double charged ion state (m/z 671.68), in the cyclic form was observed the mono charged ion state (m/z of 1325.19) and an unusual MS/MS fragmentation pattern. The differences between the forms were discrete in terms of ionic mobility, retention time (reverse phase) and net charge as function of pH. Circular dichroism spectra presented an intense negative peak at 198nm which is assigned for its disordered contents. A negative peak at 222nm in the spectrum of the circular form suggested its structure was not as disordered as the linear form. The peptides were neither haemolytic nor cytotoxic and did not inhibit phytopathogenic fungi. Surprisingly, the circular but not the linear peptide increased the proteolytic activity of papain.
O presente artigo objetiva relatar a experiência da aplicação de ferramentas digitais em encontros virtuais para o acolhimento de alunos ingressantes do curso de Odontologia da Universidade Estadual ...do Piauí (UESPI) durante a fase de isolamento social advinda da pandemia do novo coronavírus no ano de 2020. A ação extensionista foi realizada em cinco encontros virtuais por meio da plataforma de reuniões Google Meet e foram aplicadas ferramentas colaborativas como Padlet, Mentimeter e Google Forms para integração do grupo. A participação dos ingressantes foi integral, 100% dos estudantes matriculados no primeiro período do curso se fizeram presentes nos encontros. Diante das incertezas relativas ao início do período letivo no ano de 2020, a proposta realizada obteve êxito no objetivo principal de acolher os ingressantes e estabelecer o vínculo com a família do curso de Odontologia da UESPI. Desta forma a experiência mostrou-se positiva, proporcionando uma acolhida dos discentes durante o período mais crítico da pandemia de COVID-19 e forte isolamento social.
Campylobacter fetus subsp. venerealis is the etiologic agent of bovine genital campylobacteriosis, a sexually transmitted disease of cattle that is of worldwide importance. The complete sequencing ...and annotation of the genome of the type strain C. fetus subsp. venerealis NCTC 10354... are reported. (ProQuest: ... denotes formulae/symbols omitted.)
Campylobacter fetus subsp. venerealis is the etiologic agent of bovine genital campylobacteriosis, a sexually transmitted disease of cattle that is of worldwide importance. The complete sequencing ...and annotation of the genome of the type strain C. fetus subsp. venerealis NCTC 10354T are reported.
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