Periodontal condition, changes in salivary biochemical parameters, and oral health-related quality of life in patients with anorexia and bulimia nervosa.

BACKGROUND: Anorexia and bulimia nervosa can have significant effects on oral health. Assessment of enzyme concentrations in saliva can be useful for obtaining information on molecular biomarkers for the prevention, monitoring, and diagnosis of oral diseases. This study investigated the periodontal condition, changes in salivary biochemical parameters, and oral health-related quality of life (OHRQoL) in patients with anorexia and bulimia nervosa. METHODS: The study comprised 60 women patients who attended a Brazilian medical school. Participants were divided into two groups: patients with anorexia and bulimia nervosa (ABN; n = 30) and control patients (CN; n = 30). Oral clinical examinations were carried out to evaluate the periodontal condition by Community Periodontal Index, and interviews using the Oral Health Impact Profile (OHIP-14) were conducted to assess OHRQoL. Saliva samples were collected for the evaluation of salivary concentrations of total protein, alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and thiobarbituric acid reactive substance (TBARS), and salivary flow rate. RESULTS: Periodontal condition in the ABN group was significantly worse than that in the CN group. The ABN group showed significantly higher salivary concentrations of total protein, AST, ALT, and LDH than the CN group. There was no significant difference in the salivary concentrations of TBARS among the groups. The OHIP-14 score was higher in the ABN group than in the CN group. CONCLUSION: Anorexia and bulimia nervosa are associated with poor periodontal condition, elevated salivary concentrations of total protein, AST, ALT, and LDH, decreased salivary flow rate and a significant adverse impact on OHRQoL.

Chronic high glucose and insulin stimulate bone-marrow stromal cells adipogenic differentiation in young spontaneously hypertensive rats.

We evaluated whether genetic predisposition is sufficient to induce changes due to chronic high glucose (HG; 25 mmol/L) in the presence or absence of insulin (HGI; 10 µg/ml) on osteogenic differentiation and markers in bone-marrow mesenchymal stem cells (BMSCs) from young Wistar (WBMSCs) and spontaneous hypertensive rats (SBMSCs) without hypertension. HG suppressed osteogenic differentiation in both the strains, observed by mineralization inhibition and decreased levels of the osteogenic markers Runx2, osterix, osteopontin, and bone sialoprotein, compared to osteogenic medium (OM) cells. In WBMSCs, the effects of HG were associated with the down regulation of ERK1/2 and up regulation of p38 activities; however, HGI did not revert the effects of HG on MAPK activities. Moreover, HG did not affect MAPK signaling in SBMSCs compared to that in OM. HGI increased mineralization in WBMSCs compared to that in OM, but not in SBMSCs. High expression of peroxisome proliferator-activated receptor-gamma and glucose transporter type 4 in OM could be related with the predisposition to adipogenic differentiation noted in SBMSCs and was confirmed by emergence of adipocyte-like cells by HGI treatment. Downregulation of p38 and upregulation of JNK activities were observed in both BMSCs treated with HGI compared to those treated by HG. Ma (osmotic control) also suppressed osteogenic differentiation in both the strains. In conclusion, we demonstrated that SBMSCs from young spontaneous hypertensive rats, without hypertension but with genetic and epigenetic predisposition, exhibited decreased osteoblastic differentiation under HG and HGI did not revert the effects of HG in SBMSCs but increased adipogenic differentiation.

Apocynin reduces blood pressure and restores the proper function of vascular endothelium in SHR.

This study has evaluated how the vascular endothelium of hypertensive rats chronically treated with apocynin affects acetylcholine (ACh), sodium nitroprusside (SNP), and phenylephrine (PE) action on the nitric oxide (NO) signal transduction pathway in endothelial (EC) and vascular smooth muscle cells. Treatment with apocynin significantly reduced the mean arterial pressure in spontaneously hypertensive rats (SHR). In addition, apocynin improved the impaired ACh hypotensive effect on SHR. Although systemic oxidative stress was high in SHR, SHR treated with apocynin and normotensive rats presented similar systemic oxidative stress levels. Endothelium significantly blunted PE contractions in intact aortas of treated SHR. The ACh effect was impaired in resistance arteries and aortas of SHR, but this same effect was improved in treated SHR. The SNP potency was higher in intact resistance arteries of treated SHR than in intact resistance arteries of untreated SHR. NO and calcium concentrations increased, whereas reactive oxygen species levels decreased in EC of treated SHR. Aortas of untreated and treated SHR did not differ in terms of sGC alpha or beta units expression. Aorta of treated SHR expressed higher eNOS levels as compared to aorta of untreated SHR. The study groups did not differ with respect to NOX1, NOXO1, or NOX4 expression. However, treatment with apocynin normalized overexpression of NOX2 and its subunit p47phox in aortas of SHR. Based on all the results presented in this study, we suggest apocynin increases NO biovailability by different mechanisms, restoring the proper function of vascular endothelium in SHR.

Hypertension modifies OPG, RANK, and RANKL expression during the dental socket bone healing process in spontaneously hypertensive rats.

OBJECTIVE: The aim of this study was to evaluate the dental socket bone healing process by histomorphometric and immunohistochemical analysis of osteoprotegerin (OPG), receptor activator of nuclear factor-κß (RANK), and receptor activator of nuclear factor-κß ligand (RANKL) proteins in spontaneously hypertensive rats (SHR). MATERIALS AND METHODS: Under general anesthesia, 25 Wistar rats and 25 SHRs underwent upper right incisor extraction. Rats were euthanized after 7, 14, 21, 28, or 42 days of dental extractions. Histomorphometric and immunohistochemical analyses of OPG, RANK, and RANKL proteins were performed. RESULTS: Histomorphometric results showed decreased bone healing and reduced bone trabecular thickness in SHRs. Immunohistochemical reactions showed intense RANKL and RANK immunolabeling at 14 and 28 postoperative days and mild OPG immunolabeling at 7, 14, and 21 days after surgery in SHRs. CONCLUSION: The results of this study show that RANK, RANKL, and OPG immunolabeling was altered in SHRs, and these results are associated with bone healing delay and decreased trabecular thickness in SHRs. CLINICAL RELEVANCE: Hypertension alters the expression of RANK, RANKL, and OPG and delays the socket bone healing process. These alterations could influence some dental procedures such as orthodontic treatment and implant placement.

The PI3K-Akt-eNOS pathway is involved in aortic hyporeactivity to Phenylephrine associated with late pregnancy in spontaneously hypertensive rats.

AIM: This study aimed to evaluate the effects of Wortmannin, an inhibitor of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt), on aortic hyporeactivity to Phenylephrine (Phe) and nitric oxide bioavailability associated with pregnancy in hypertensive rats. MAIN METHODS: The intact aortic rings of pregnant and non-pregnant Wistar or spontaneously hypertensive rats (SHRs) were stimulated with Phe (1nmol/L to 10mmol/L) before and after incubation with Wortmannin (10nmol/L, 30min). Western blot experiments analyzed the expression of phosphorylated PI3K [p85-PI3K], Akt [p-Akt (Ser 473)] and eNOS [p-eNOS (Ser 1177)] in aorta homogenates of pregnant and non-pregnant Wistar rats or SHRs. The effect of Wortmannin (10nmol/L) on the cytosolic concentrations of nitric oxide (NO; measured using 4,5-diaminofluorescein diacetate [DAF-2DA], 10mmol/L), Ca(2+) (using Fluo 3-AM, 5µmol/L) and reactive oxygen species (ROS; using dihydroethidium [DHE], 2.5mmol/L) were measured fluorimetrically in freshly isolated endothelial cells. KEY FINDINGS: Wortmannin increases the reactivity of the aorta to Phe and decreases NO concentrations in the aortic endothelial cells of pregnant Wistar rats and SHR. SIGNIFICANCE: The PI3/AKT/endothelial nitric oxide synthase (eNOS) pathway contributes to aortic hyporeactivity to Phenylephrine associated with pregnancy in normo- and hypertensive rats.

Mechanisms underlying the hypotensive and vasodilator effects of Ru(terpy)(bdq)NO](3+), a nitric oxide donor, differ between normotensive and spontaneously hypertensive rats.

The endothelium impairs the vasodilator effect of Ru(terpy)(bdq)NO](3+) (TERPY) in Wistar rat aortas. We hypothesized that endothelial dysfunction could modulate TERPY׳s effect in spontaneously hypertensive rats. The present study investigated the role of the endothelium in the hypotensive and vasodilator effects of TERPY in spontaneously hypertensive rats. We observed a higher hypotensive effect of TERPY in spontaneously hypertensive than in Wistar rats. l-N(G)-Nitroarginine methyl ester, a nitric oxide synthase inhibitor, increased TERPY׳s hypotensive effect in Wistar but not in spontaneously hypertensive rats. TERPY induced a concentration-dependent vasodilator effect in aortas of both rat models. Endothelium removal or l-NAME increased TERPY׳s potency in Wistar rat aortas; this effect was decreased in spontaneously hypertensive rats. TERPY increased nitric oxide level in spontaneously hypertensive rat endothelial cells; this increase was abolished in the presence of l-NAME. In contrast, this effect was increased in Wistar rats. TERPY, with or without l-NAME, decreased levels of reactive oxygen species in spontaneously hypertensive rat endothelial cells. However, it increased these levels in Wistar rats. TERPY reduced aortic endothelial nitric oxide synthase expression in Wistar rats, but did not alter its expression in spontaneously hypertensive rats. In conclusion, different mechanisms underlie the hypotensive and vasodilator effects of TERPY in these two rat models. TERPY reduced endothelial nitric oxide synthase expression and increased reactive oxygen species production in Wistar rat aortas, but did not alter these in spontaneously hypertensive rats. Furthermore, the nitric oxide released by TERPY reacts with reactive oxygen species, decreasing their bioavailability in spontaneously hypertensive rats.

The effect of chronic treatment with fluoride on salivary activity, tooth, and bone in spontaneously hypertensive rats (SHR).

The present study evaluated the effect of chronic treatment with sodium fluoride on salivary activity, tooth, and bone in spontaneously hypertensive rats (SHR). The treatment was made with a 20-ppm NaF solution added to the drinking water for 30 days. Systolic blood pressure values were obtained by plethysmography; fluoride concentration was determined by an ion-selective electrode; calcium concentration and amylase activity were determined by commercial kits; and enamel microhardness was verified by longitudinal section. Systolic blood pressure values and animals' weight were not changed by treatment. However, the salivary flow rate-which was lowered in SHR at baseline when compared to Wistar rats-was found to be increased with the treatment with NaF. The fluoride concentration was increased in the plasma of the treated groups, even though it remained lower for the treated SHR in relation to the treated Wistar rats. Calcium concentration was decreased in the saliva and plasma of SHR treated with NaF. A reduction in the plasmatic total protein concentration was observed in SHR treated with NaF. The fluoride concentration on bone surface was found to be increased in Wistar or SHR treated with NaF. In treated SHR's femurs, it was observed a significant reduction in fluoride concentrations. Enamel microhardness of the incisor teeth was not changed by the treatment with NaF in both groups. The distribution of fluoride to the salivary glands in SHR is poor, and treatment with NaF causes a decrease in the concentration of important biochemical parameters to the salivary physiology in SHR.

Periodontal disease reduces water and sodium intake induced by injection of muscimol into the lateral parabrachial nucleus.

OBJECTIVE: Gamma-aminobutyric acid A (GABAA) receptor activation with muscimol in the lateral parabrachial nucleus (LPBN) induces water and 0.3M NaCl intake. The purpose of this study was to investigate whether a local inflammatory event, such as periodontal disease (PD), is able to alter the effects of muscimol on water and 0.3M NaCl intake in fluid-replete rats and in rats treated with furosemide (FURO) combined with captopril (CAP) injected subcutaneously. DESIGN: Male Wistar rats were divided into two groups: with PD and those without PD (control condition). Fifteen days after PD, both groups had cannulas implanted bilaterally into the LPBN. RESULTS: In fluid-replete rats without PD, injections of muscimol (0.5nmol/0.2µl) into the LPBN induced 0.3M NaCl and water intake and a pressor response. In fluid-replete rats with PD, a decrease was observed in water intake and pressor response but not in 0.3M NaCl intake. In control rats with FURO+CAP treatment, injections of muscimol into the LPBN increased 0.3M NaCl and water intake. In PD rats with FURO+CAP treatment, a decrease was observed in 0.3M NaCl and water intake after muscimol in the LPBN. Alveolar bone loss and interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) plasmatic concentration were higher in PD rats in comparison with controls. CONCLUSION: These results suggest that PD is able to reduce the pressor response and the dipsogenic and natriorexigenic effects induced by the activation of GABAA receptors in the LPBN, probably due to the elevation of the plasmatic concentration of pro-inflammatory cytokines IL-6 and TNF-α.

Maternal periodontal disease in rats decreases insulin sensitivity and insulin signaling in adult offspring.

BACKGROUND: Periodontal disease during pregnancy has been recognized as one of the causes of preterm and low-birth-weight (PLBW) babies. Several studies have demonstrated that PLBW babies are prone to developing insulin resistance as adults. Although there is controversy over the association between periodontal disease and PLBW, the phenomenon known as programming can translate any stimulus or aggression experienced during intrauterine growth into physiologic and metabolic alterations in adulthood. The purpose of the present study is to investigate whether the offspring of rats with periodontal disease develop insulin resistance in adulthood. METHODS: Ten female Wistar rats were divided into periodontal disease (PED) and control (CN) groups. All rats were mated at 7 days after induction of periodontal disease. Male offspring were divided into two groups: 1) periodontal disease offspring (PEDO; n = 24); and 2) control offspring (CNO; n = 24). Offspring body weight was measured from birth until 75 days. When the offspring reached 75 days old, the following parameters were measured: 1) plasma concentrations of glucose, insulin, fructosamine, lipase, amylase, and tumor necrosis factor-α (TNF-α); 2) insulin sensitivity (IS); and 3) insulin signal transduction (IST) in insulin-sensitive tissues. RESULTS: Low birth weight was not detected in the PEDO group. However, plasma concentrations of glucose, insulin, fructosamine, lipase, amylase, and TNF-α were increased and IS and IST were reduced (P <0.05) in the PEDO group compared with the CNO group. CONCLUSION: Maternal periodontal disease may induce insulin resistance and reduce IST in adult offspring, but such alterations are not attributable to low birth weight.

Spontaneously hypertensive rat as experimental model of salivary hypofunction.

OBJECTIVE: To analyse the salivary activity in spontaneously hypertensive rats (SHRs) evaluating biochemical parameters of saliva in 4-week-old and 12-week-old animals. DESIGN: Systolic blood pressure (SBP) was recorded by tail plethysmography. The salivary flow rate was stimulated by pilocarpine (SFR). The pH and salivary buffering capacity (SBC) were evaluated with a specific electrode. The concentrations of fluoride ([F(-)]) and calcium ([Ca(++)]) ions were determined using an electrode connected to a calibrated ion analyser. The total protein concentration was determined by Lowry method, and amylase activity by kinetic method. The salivary IgA was determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: The SFR, [F(-)] and [Ca(++)] increased with age in normotensive rats, however no alteration in pH, total protein and IgA was observed between 4 and 12 weeks old Wistar rats. SBC decreased with age in Wistar rats. The SFR was not altered between SHRs in different ages and it was lower in 12 weeks old SHR when compared to Wistar rats. An increase in the protein concentration, and in the amylase activity and [F(-)] was observed with the development of SHR. Unaltered SBC, salivary IgA and [Ca(++)] were observed in 12 weeks old when compared to 4 weeks old SHR. The [Ca(++)] ions were reduced in saliva of SHR than that of Wistar rats at 12 weeks. A lower pH was observed in saliva of Wistar than that of SHR at 12 weeks. CONCLUSIONS: SHR is an experimental model of salivary hypofunction, the decreased SFR observed in SHR at different ages was associated to salivary biochemical parameter alterations.

Periodontal disease decreases insulin sensitivity and insulin signaling.

BACKGROUND: The purpose of this study is to investigate whether local inflammatory events, such as periodontal disease, are able to increase tumor necrosis factor-alpha (TNF-α) plasmatic concentration and decrease insulin sensitivity and insulin signaling in non-diabetic rats. METHODS: Forty-eight male Wistar rats (2 months old) were divided into two groups, with either ligature-induced periodontal disease (LPD) or control conditions (CN). Experiments were performed in both groups 28 days after ligature placement. Plasmatic concentration of glycemia and TNF-α (n = 10) were analyzed by the glucose oxidase and enzyme-linked immunosorbent assay method, respectively. Insulin sensitivity (n = 7) was measured using the insulin tolerance test. Insulin signal transduction (n = 7) was measured by pp185 tyrosine phosphorylation status in insulin-sensitive tissues using the Western blotting method. RESULTS: The LPD group showed decreased insulin sensitivity (P <0.05), although no glycemic alterations were noted (P >0.05). TNF-α plasmatic concentration was higher in LPD rats compared to CN rats. In addition, a decrease in the pp185 tyrosine phosphorylation status was observed after insulin stimulus in both white adipose and skeletal muscle tissues of the LPD group compared with the CN group. CONCLUSIONS: LPD is able to cause alterations to both insulin signaling and insulin sensitivity, probably because of the elevation of TNF-α plasmatic concentration. Thus, the present results emphasize the importance of the prevention of local inflammatory diseases, such as periodontitis, to prevent diabetes mellitus.

Effect of lifelong high- or low-salt intake on blood pressure, left ventricular mass and plasma insulin in Wistar rats.

BACKGROUND: Salt restriction is recommended for hypertension treatment to reduce blood pressure, but its effect on some risk factors is still a matter of discussion. The aim of this study was to observe the effect of a long period of salt restriction or overload on blood pressure, left ventricular mass (LVM), kidney mass (KM), glucose tolerance, and plasma insulin. METHODS: Male Wistar rats were fed from weaning with a low-salt diet (LSD) or a high-salt diet (HSD) until 72 weeks of age. After 48 weeks, the diets were changed in half of the rats: HSD until 48 weeks and then LSD (LHSD) and LSD until 48 weeks and then HSD (HLSD). Body weight, blood pressure, electrolyte excretion, creatinine clearance, plasma renin activity, LVM, KM, and intravenous glucose tolerance test with insulin determinations were evaluated. RESULTS: Blood pressure, LVM and KM were higher on the HSD than on the LSD. Blood pressure was lower on the LHSD than on the HLSD. There were no differences in LVM and KM on the LHSD compared with the HLSD. The relationship between area under the curve (AUC) of insulin and glucose during the intravenous glucose tolerance test was higher on the LSD. No differences were detected in AUC between the two groups of rats whose diet were inverted with 48 weeks of age. CONCLUSIONS: A chronic HSD increases blood pressure, LVM, and KM and a chronic LSD increases plasma insulin in response to a glucose challenge in aging rats. The hypotensive effect of salt restriction is not modified by a previous long period on a HSD.

Calorie restriction reduces pinealectomy-induced insulin resistance by improving GLUT4 gene expression and its translocation to the plasma membrane.

The present study aimed to investigate insulin sensitivity and GLUT4 expression protein in pinealectomized rats, as well as to determining the effects of melatonin and calorie restriction on the changes induced by pinealectomy. Wistar rats were pinealectomized (Pinx) or sham operated (Sham), and studied 30 days later. Melatonin replacement treatment (50 g/100 g body weight) was continued for 30 days after pinealectomy. Calorie restriction was performed by offering 60% of the standard food intake. In vivo insulin sensitivity was evaluated using the glucose disappearance constant (kITT) during an insulin tolerance test, and GLUT4 mRNA and protein were assessed by Northern and Western blotting, respectively. The in vitro effect of melatonin on GLUT4 protein content in plasma membrane was investigated in adipocytes isolated from intact rats. Compared with Sham rats, Pinx rats showed decreased kITT (40%), GLUT4 expression in white adipose tissue (WAT, approximately 70%), and unchanged GLUT4 expression in skeletal muscle. Melatonin treatment in Pinx rats restored the kITT and GLUT4 protein to control values. No in vitro effects of melatonin (10-9 m) upon GLUT4 protein were observed. Calorie restriction of Pinx rats increased their kITT value ( approximately 40%), total GLUT4 protein content ( approximately 240%) and its translocation to the plasma membrane ( approximately 80%) in WAT. The results show that pinealectomy, for lack of melatonin, decreased insulin sensitivity as well as GLUT4 gene expression. Calorie restriction improved insulin sensitivity in Pinx rats, and this was related to increased GLUT4 gene expression and insulin-induced GLUT4 translocation to the plasma membrane in WAT.