Lucila Busch

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.

Differences in the regulatory mechanism of amylase release by rat parotid and submandibular glands

It is not known whether the mechanisms involved in amylase release in submandibular and parotid glands are similar. Here, the participation of different signalling pathways in amylase release by the parotid and submandibular glands of the male rat was compared by studying the secretory response after beta-adrenergic stimulation. The beta-adrenergic agonist isoproterenol induced an increase of cAMP in both salivary glands, but while in the parotid it triggered amylase release, in the submandibular it was unable to increase amylase secretion. Parotid amylase release was dependent on adenylate cyclase activation, as SQ-22536 inhibited the secretory effect. In contrast, submandibular amylase secretion did not depend on the intracellular concentration of cAMP, as SQ-22536 did not modify its secretory response. Moreover, other activators of adenylate cyclase, such as forskolin and prostaglandin E2, also failed to modify amylase release by the submandibular gland. Neither ionophores nor calcium-blocking agents, as well as calcium-calmodulin and nitric oxide synthase inhibitors, were effective in modifying basal amylase release by the submandibular gland. However, the disruption of microfilaments with cytochalasin B, but not the disruption of microtubules with colchicine, prevented amylase release in that gland. It is concluded that amylase exocytosis in the submandibular gland is a constitutive non-regulated phenomenon, as it is independent of extracellular or intracellular signals. It depends only on the integrity of the microfilaments, probably used by the vesicles to travel from the Golgi apparatus to the plasma membrane.

Effects of castration on cannabinoid CB1 receptor expression and on the biological actions of cannabinoid in the parotid gland

1 In the present study, we examined whether cannabinoid receptor expression and the effects of receptor stimulation vary as a function of gonadal status in a peripheral tissue, namely the male rat parotid gland. Four groups of male rats were studied: gonadal intact, castrated, castrated testosterone (1 mg/100 g bodyweight) treated and gonadal intact testosterone treated. 2 The results showed that the density of CB1 receptors decreased after castration and that receptor density was restored to control values after testosterone treatment. This decrement was associated with a decrease of anandamide (10‐10 to 10‐5 mol/L)‐induced cAMP accumulation and amylase release without changes in the anandamide‐induced inhibition of Na+/K+‐ATPase activity. 3 Castration did not modify either the subtype of cannabinoid receptor involved in the actions of anandamide or drug affinity for the receptor. 4 The mechanism underlying anandamide‐induced cAMP accumulation, amylase release and inhibition of Na+/K+‐ATPase activity, namely through the activation of adenylyl cyclase, was the same in control and castrated rats. 5 Basal cAMP accumulation, amylase release and Na+/K+‐ATPase activity were not altered by castration. 6 Castration had no effect on the concentration of total protein. 7 It can be concluded that CB1 cannabinoid receptor expression is regulated by testosterone in male rat parotid gland and this has functional implications for cAMP accumulation and amylase release.

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.

Total salivary nitrates and nitrites in oral health and periodontal disease

It is well known that nitrites are increased in saliva from patients with periodontal disease. In the oral cavity, nitrites may derive partly from the reduction of nitrates by oral bacteria. Nitrates have been reported as a defence-related mechanism. Thus, the aim of the present study was to determine the salivary levels of total nitrate and nitrite and their relationship, in unstimulated and stimulated saliva from periodontal healthy subjects, and from patients with chronic periodontal disease. Nitrates and nitrites were determined in saliva from thirty healthy subjects and forty-four patients with periodontal disease. A significant increase in salivary nitrates and nitrites was observed. Nitrates and nitrites concentration was related to clinical attachment level (CAL). A positive and significant Pearsons correlation was found between salivary total nitrates and nitrites. Periodontal treatment induced clinical improvement and decreased nitrates and nitrites. It is concluded that salivary nitrates and nitrites increase, in patients with periodontal disease, could be related to defence mechanisms. The possibility that the salivary glands respond to oral infectious diseases by increasing nitrate secretion should be explored further.

Castration decreases amylase release associated with muscarinic acetylcholine receptor downregulation in rat parotid gland

The mechanism and receptor subtypes involved in carbachol‐stimulated amylase release and its changes after castration were studied in parotid slices from male rats. Carbachol induced both amylase release and inositol phosphate (IP) accumulation in parotid slices from control and castrated rats, but castration induced a decrease of carbachol maximal effect. The effect of castration was reverted by testosterone replacement. The selective M1 and M3 muscarinic receptor antagonists, pirenzepine and 4‐diphenylacetoxy‐N‐methylpiperidine methiodide, respectively, inhibited carbachol‐stimulated amylase release and IP accumulation in a dose‐dependent manner in parotid slices from control and castrated rats. A diminution of binding sites of muscarinic receptor in parotid membrane from castrated rats was observed. Competition binding assays showed that both, M1 and M3 muscarinic receptor subtypes are expressed in membranes of parotid glands from control and castrated rats, M3 being the greater population. These results suggest that amylase release induced by carbachol in parotid slices is mediated by phosphoinositide accumulation. This mechanism appears to be triggered by the activation of M1 and M3 muscarinic receptor subtypes. Castration induced a decrease of the maximal effect of carbachol evoked amylase release and IP accumulation followed by a diminution in the number of parotid gland muscarinic acetylcholine receptors.

β-Adrenoceptor alterations coupled with secretory response and experimental periodontitis in rat submandibular glands

In this paper we have studied the influence of a well-established rat model of periodontitis on resting and adrenergic-stimulated mucin secretion from rat submandibular glands. The selective beta(1)-receptor subtype agonist, dobutamine, induced mucin secretion while the selective beta(2)-, alpha(1)- and alpha(2)-agonists, soterenol, phenylephrine and clonidine, respectively, did not. In rats subjected to ligature-induced periodontitis mucin release, under unstimulated conditions (basal values), was significantly increased. This increment was abolished in the presence of propranolol and atenolol. Isoproterenol, concentration-dependent, increased mucin release in control and in ligature-induced periodontitis rats. Maximal effect of isoproterenol was decreased in rats with ligature while EC(50) was increased. Neither, the inhibition of NOS by l-NMMA nor the inhibition of COX by indomethacin could revert the effect of ligature on mucin release under unstimulated and isoproterenol-stimulated conditions. The inhibition of adenylyl cyclase by SQ 22536 resulted in a right shift of isoproterenol concentration-response curves in both groups, control and with ligature and returned basal values of rats with ligature to control ones. beta-Receptor population was decreased in submandibular gland membranes from rats with ligature without changes in affinity. Potencies of the beta-receptor antagonists in the competition studies were similar in both groups under study, control and with ligature. We conclude that in rats subjected to ligature-induced periodontitis unstimulated mucin secretion is increased. The increment seems to be due to an activation of the sympathetic system since it is inhibited by the beta-adrenoceptors antagonists and by the inhibition of the adenylyl cyclase. We can speculate that inflammatory mediators from the experimental periodontitis could be involved in the mechanism underlying the activation of the sympathetic system.

Long-term treatment with fluoxetine associates with peripheral effects on rat vas deferens contractility

The aim of this work was to study whether long-term treatment with fluoxetine could induce peripheral effects by modifying vas deferens contractile activity. For this purpose the contractile response to NE, and 5-HT of vas deferens isolated from male Wistar rats that received fluoxetine 10 mg/kg/day i.p., during 21 days, was studied using the isolated organ bath technique. Results show that vas deferens of treated rats presented spontaneous activity, an effect that was abolished by prazosin and isoproterenol and that was not affected by nitroprusside or indomethacin. In addition, fluoxetine did not modify the response to calcium suggesting that spontaneous activity was not a consequence of an abnormal calcium movement. Fluoxetine induced a significant increase in the response of vas deferens to 5-HT and to low NE concentrations while NE maximal effect was unaffected. Fluoxetine treatment did not modify the binding parameters of [3H]-prazosin to vas deferens. It is concluded that long-term treatment with fluoxetine modifies vas deferens contractile activity. This effect could be the result of an alteration of adrenergic neurotransmission and could account for some of the untoward effects observed during clinical course with fluoxetine.

Association between Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis in subgingival plaque and clinical parameters, in Argentine patients with aggressive periodontitis

BACKGROUND Aggregatibacter actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) have been associated with aggressive (AgP) and chronic periodontitis. OBJECTIVE The aim of this study was to evaluate the levels of Aa and Pg in gingival crevicular fluid (GCF) of patients with AgP and its relation with clinical parameters. DESIGN Sixteen females and fourteen males with clinical diagnosis of AgP aged 17-23 years and their matchs controls, were included in this study. Clinical recording concerning probing pocket depth, clinical attachment level, plaque index and gingival bleeding index were performed at baseline, 30 and 60 days after baseline. After clinical examination GCF samples were analyzed for Aa and Pg with a real-time polymerase chain reaction technique. Patients group was treated with a combined of mechanical and oral antibiotic therapy (doxycycline 100 mg/day, during 21 days). A multivariate analysis was used to determine the relationship between Aa and Pg counts with clinical parameters. RESULTS GCF from all subjects was positive for Aa and PG. In controls Pg concentration was higher than Aa (Pg: 42,420 ± 3,034 copies/ml; Aa: 66.6 ± 5.4 copies/ml p < 0.001) while in patients both microbes showed the same concentration (Aa: 559,878 ± 39,698 Pg: 572,321 ± 58,752). A significant and positive correlation was observed between counts of Aa and Pg (R square: 0.7965, p < 0.0001). Female showed more counts/ml. Aa might be closely associated with clinical parameters while Pg did not. At 30 and 60 days Aa counts in patients were similar to controls while Pg counts were equal to baseline. However, in spite of Pg presence a clinical improvement was observed in all patients. CONCLUSIONS In our population the presence of Aa may be associated with AgP while Pg may be in GCF as an opportunistic pathogen which might caused disease when the ecological balance was favorable.

Comparison of salivary levels of mucin and amylase and their relation with clinical parameters obtained from patients with aggressive and chronic periodontal disease

Objective Salivary mucin and amylase levels are increased in patients with chronic periodontitis (CP). Due to the fact that aggressive periodontitis (AgP) not only differs from chronic periodontitis in terms of its clinical manifestation, the aim of this study was to compare salivary mucin and amylase levels and their relation to the clinical parameters of patients with aggressive periodontitis with that of patients with chronic periodontitis. Material and Methods Eighty subjects were divided into two groups: 20 patients with AgP and their 20 matched controls and 20 patients with CP and their 20 matched controls, based on clinical attachment loss (CAL), probing pocket depth (PPD) and bleeding on probing (BOP). Whole unstimulated saliva was obtained and mucin, amylase and protein were determined by colorimetric methods. Pearson’s correlation analysis was used to determine the relationship between salivary mucin, amylase and protein levels and the clinical parameters. Results Salivary mucin, amylase and protein levels were increased in patients with AgP and CP but there were no differences between them or between control groups. Pearson’s correlation analysis, determined in the entire subjects studied, showed a positive and significant correlation of mucin, amylase and proteins with CAL and PPD and a negative correlation with the flow rate. When Pearson’s correlation analysis was carried out in each group separately, Fisher’s z transformation showed no significant difference between both groups. Conclusion Comparison of the salivary levels of mucin, amylase and protein and their relationship with clinical parameters of AgP patients with that of CP patients revealed no differences between both groups.