Aplicaciones de la informática en el estudio de productos naturales / Applications of informatics to the study of natural products

En los últimos tiempos, las técnicas computacionales se han constituido en valiosas herramientas para la investigación de sistemas biológicos. Ellas pueden guiar proyectos y complementar métodos experimentales en diversas áreas de aplicación, como la medicina, alimentación y agricultura. En este artículo resumimos y actualizamos los principales conocimientos acerca de los métodos utilizados por la bioinformática y brindamos algunos ejemplos de sus contribuciones en distintos campos. Enfatizamos en el diseño y descubrimiento de nuevas drogas de origen natural, principalmente antimicrobianas. En este sentido, la búsqueda de nuevos medicamentos y estrategias farmacológicas está plenamente justificada por distintas razones, que incluyen la emergencia de resistencia e interacciones farmacológicas, particularmente en pacientes inmunocomprometidos.

In the last times, computational techniques have become valuable tools for research of biological systems. They can lead and complementexperimental methods in different fields of application such as medicine, bromatology and agriculture.In this review we summarize the main knowledge on bioinformatic tools and give some examples of their contributions in diverseknowledge areas. We make emphasis in the design and discovery of new potential drugs, mainly antimicrobial agents of natural origin.In this sense, the search for new medicaments or pharmacological strategies is fully justified because of different reasons, includingemergence of resistance and pharmacological interactions, in particular in immunocompromised patients.

Relationship between salivary leukotriene B4 levels and salivary mucin or alveolar bone resorption, in subjects with periodontal health and disease.

OBJECTIVE: Here we determine the salivary levels of leukotriene B4 (LTB4 ) and its relation with salivary mucin and alveolar bone level. BACKGROUND: LTB4 is a membrane-derived lipid mediator formed from arachidonic acid. It is among the most potent stimulants of polymorphonuclear leukocytes providing the first host defense against infections. Leukotrienes also induce bone resorption. Because LTB4 is present in the oral cavity the aim of the present study was to explore the role of LTB4 in patients with periodontal disease. METHODS: Eighty-one subjects were clinically examined and distributed into four groups, namely, clinically healthy, mild, moderate and severe periodontitis, according to periodontal status, classified into values of clinical attachment level and probing pocket depth. Unstimulated saliva was collected for 5 min. Salivary LTB4 was determined by an immune assay method, mucin was determined by a colorimetric method and radiographic assessment used to determine alveolar bone level. RESULTS: Patients with mild periodontitis showed a decrease in salivary LTB4 levels while patients with severe periodontitis showed increased LTB4 levels. A significant positive correlation was observed between salivary LTB4 and clinical attachment level, salivary mucin concentration or alveolar bone level. CONCLUSION: The close relation between salivary LTB4 and mucin levels suggested that LTB4 might be involved in the defense mechanism of the oral cavity. The correlation of LTB4 with the alveolar bone level indicates that they are one of the mediators responsible for bone resorption.

Relationship between salivary mucin or amylase and the periodontal status.

OBJECTIVE: Here we determine the relationship between salivary levels of mucin and amylase and the clinical parameters of periodontal disease before and after periodontal treatment. SUBJECTS: Ninety two subjects were clinically examined and distributed into four groups namely clinically healthy, mild, moderate and severe periodontitis, according to the periodontal status, classified according the values of clinical attachment level (CAL) and probing pocket depth (PPD). Unstimulated saliva was collected for 5 min. Salivary proteins, amylase and mucin were determined by colorimetric methods. RESULTS: A significant positive correlation (P < 0.0001) was observed between salivary mucin, amylase or protein and PPD or CAL before periodontal treatment while flow rate showed a negative correlation. Mucin and amylase output also showed a positive correlation with PPD or CAL. After treatment, the improvement of clinical parameters was accompanied by a diminution of salivary mucin, amylase or protein concentration and output in moderate and severe group. CONCLUSIONS: The increment of mucin and amylase output in relation to periodontal status indicates that salivary glands respond to the disease by increasing the protective potential of saliva when necessary and return to the normal rate of secretion after the resolution of the inflammatory process.

Determination of salivary levels of mucin and amylase in chronic periodontitis patients.

BACKGROUND AND OBJECTIVE: Patients with periodontal disease show differences in the profile of proteins in whole saliva. This profile reflects the nature and amplitude of the host response to a periodontal microbial challenge. Since periodontitis is a chronic inflammatory disease with different progression stages, the aim of the study was to evaluate the host response in these different clinical stages by assessing salivary flow rate, the concentrations of proteins and mucin and the amylase activity. MATERIAL AND METHODS: Sixty adult subjects were clinically examined and distributed into four groups (n = 15) according to the periodontal status, namely, healthy, mild, moderate and severe periodontitis. Whole saliva was collected for 5 min, followed by a second 5 min sampling period with stimulation by chewing a paraffin block, and flow rate was determined. Salivary proteins, amylase and mucin were determined by colorimetric methods. RESULTS: The concentrations of proteins, amylase and mucin increased in subjects with moderate and severe periodontal disease in unstimulated saliva, while flow rate decreased. A positive correlation was found between proteins and amylase or mucin concentrations among the different groups, indicating that the concentrations changed in the same way, being the response of salivary glands to the disease, possibly to enhance the protective potential of saliva. Mucin concentration was lower in the mild periodontitis group. Mechanical stimulation induced an increase in flow rate and output of proteins, amylase and mucin. CONCLUSION: Periodontitis induces an increase in the output of proteins, including mucin and amylase, thereby enhancing the protective potential of saliva, but this is accompanied by a decrease in flow rate.

Increase nitric oxide synthase activity in parotid glands from rats with experimental periodontitis.

OBJECTIVE: In this study we investigated the activity of the nitric oxide synthase (NOS) in parotid glands from rats with experimental periodontitis and controls. METHODS: Periodontitis was produced by a ligature placed around the cervix of the two lower first molar. Experiments were carried out 22 days after the ligature. RESULTS: Ligation caused an increase in parotid NOS activity. The selective blocker of the inducible isoform of the enzyme partially inhibited its activity in parotid glands from rat with ligature. In controls, the activity was partially inhibited by the antagonists of the selective neural and endothelial isoforms. NOS activity in rats with ligature was cyclic adenosine monophosphate (cAMP)-dependent while in controls it was calcium-dependent. Prostaglandin E2 concentration was increased in parotid gland from rats with ligature. The inhibitor of prostaglandin production, FR 122047, diminished both, prostaglandin production and NOS activity. In rats with ligature unstimulated amylase released is increased. Both, prostaglandin and NOS were involved in the increment of amylase release. CONCLUSION: It can be concluded that in parotid glands from ligated rats, prostaglandin E2 production is increased and, through cAMP accumulation, activates the inducible NOS isoform. The increment of nitric oxide production participates in the increase in basal amylase release.