Significantly reduced salivary nitric oxide synthesis in patients with Parkinson's disease

Effectiveness of thyme honey in the management of xerostomia in geriatric patients with end-stage renal disease: a randomized controlled clinical trial with a biochemical assessment

BACKGROUND

Taking into consideration the value of the oral health condition in geriatric people with end-stage renal disease (ESRD) associated with xerostomia and believing that salivary stimulants or substitutes could potentially be used to manage this condition. This study aimed to evaluate the clinical effectiveness of thyme honey as oral rinse in geriatric patients with ESRD using the subjective dry mouth score as a primary objective and to assess the effect of thyme honey on the salivary nitric oxide level, salivary flow rate, and salivary ph in addition to objective dry mouth score as a secondary objective.

METHODS

This was a single blinded randomized controlled trial with two equal arms, the interventional arm (thyme honey oral rinse) and the control arm (saline). Twenty-eight geriatric patients with ESRD undergoing hemodialysis complained of xerostomia were recruited from the renal dialysis center. Patients in both arms followed the same administration protocol either with thyme honey oral rinse or saline. The following clinical parameters (the subjective and objective dry mouth scores, salivary flow rate, salivary ph, and salivary nitric oxide (NO) levels) were evaluated for both groups at different intervals (baseline, 1 week, and 1 month).

RESULTS

In the current study, it was found that both the subjective and objective dry mouth scores were significantly lower after one month of using thyme honey oral rinse (1.86 ± 0.66B) and (2.21 ± 0.43B) respectively, than the control group (3.07 ± 0.73B) and (3.07 ± 0.83B), respectively with a (p < 0.001). Also, the salivary flow rate was significantly higher after one month of using thyme honey oral rinse (1.56 ± 0.51A), than the control group (0.78 ± 0.27A) with a (p < 0.001). For the NO levels, there was a significant increase in measured value after 1 month in the intervention group (p < 0.001), while for the control group the change was not statistically significant (p = 0.166).

CONCLUSIONS

The results of the current study have revealed the efficacy of Thyme honey oral rinse in the management of xerostomia in geriatric patients with ESRD. Trial registration The ClinicalTrials.gov Identifier for this study is NCT05247008.

Salivation in Parkinson's disease: A scoping review

OBJECTIVES

We aimed to provide an overview of the available literature that includes both objective assessments (namely hypersalivation and hyposalivation) and the subjective experience (namely xerostomia and drooling) of salivary problems in patients with Parkinson's disease.

BACKGROUND

In patients with Parkinson's disease, there may be complaints of salivary problems such as xerostomia or drooling. This can have consequences for their oral health and quality of life. To date, systematic reviews have focused on drooling only.

MATERIALS AND METHODS

A literature search in 4 databases was performed up to 12 February 2021. Two researchers independently assessed studies for eligibility.

RESULTS

In total, 63 studies were included. The prevalence of self-reported xerostomia ranged from 49% to 77%, and that of self-reported drooling ranged from 5% to 80%. Ten articles reported a significantly lower mean salivary flow in patients with Parkinson's disease than in controls. None of the articles with both a control group and a patient group reported a significantly higher salivary flow in patients with Parkinson's disease. When questioned about subjective salivary problems, a significantly higher prevalence of both xerostomia (7 studies) and drooling (14 studies) was found in patients with Parkinson's disease than in controls. Patients with Parkinson's disease have a lower salivary flow rate and higher prevalence of both xerostomia and drooling than controls.

CONCLUSION

The complexity of salivary problems present in patients with Parkinson's disease necessitates a multidisciplinary approach in order to avoid mutually counteracting treatments from different healthcare professionals.

Evaluation of salivary heme oxygenase-1 as a potential biomarker of early Parkinson's disease

BACKGROUND AND HYPOTHESIS

To date, there are no chemical analytes, including biochemical indices of oxidative stress, metabolites of α-synuclein protein, and differential protein expression patterns on proteomic profiling, for use in clinics as a diagnostic biomarker of idiopathic PD.

OBJECTIVES

Heme oxygenase-1 has been implicated in the pathogenesis of PD. The objective of this study is to ascertain whether salivary heme oxygenase-1 may serve as a biomarker for early idiopathic PD.

METHODS

Fifty-eight PD patients and 59 non-neurological disease controls were recruited. Levels of heme oxygenase-1 expression were assayed using enzyme-linked immunosorbent assay and western blot analysis of whole, unstimulated saliva. Analyses were adjusted by sex, l-dopa exposure, and relevant comorbidities.

RESULTS

We documented: (1) the presence of 32-kDa heme oxygenase-1 protein in human saliva; (2) significantly higher mean heme oxygenase-1 protein concentrations in saliva of PD patients relative to control values; (3) no variability in salivary heme oxygenase-1 levels with sex, age, l-dopa equivalence, or comorbidities; and (4) significantly higher mean salivary heme oxygenase-1 concentrations in patients with H & Y stage 1 PD (early) than control subjects and stage 2 and stage 3 PD patients. The area under the receiver operating characteristic curve that separated controls from PD H & Y stage 1 was 76% (95% confidence interval: 63-90).

CONCLUSIONS

Salivary heme oxygenase-1 concentrations may provide a useful, noninvasive, and relatively inexpensive biomarker of early idiopathic PD. © 2018 International Parkinson and Movement Disorder Society.

Significance of Nitric Oxyde Saliva Concentration of the Patients with Renal Failure on Hemodialysis

Introduction:

An increase in nitric oxide (NO) synthesis concentration could help alleviate some pathological changes directly related to uremia.

Aim:

To investigate the concentration of nitric oxide in saliva of patients with terminal stage of chronic renal failure on hemodialysis and to investigate the effect of hemodialysis on concentration of nitric oxide in saliva of the patients with terminal stage of chronic renal failure on hemodialysis.

Material and Methods:

The study had a prospective character and included 60 respondents of both sexes, at age between 20 and 60 years. The control group included 30 healthy volunteers of both sexes (15 men and 15 women) of the same age, who were based on subjective and objective health status without any manifestations of pathophysiological changes. The group of patients with terminal stage of chronic renal failure on hemodialysis involved 30 patients of both sexes (15 men and 15 women). Inclusion criteria: hemodialysis duration more than 6 months and age between 20 and 60 years.

Results:

The amount of non-stimulated saliva collected during 15 minutes in patients with chronic renal failure was lower by 31.3% compared to the control group of healthy subjects (p<0.0001). Concentration of NO in saliva in patients with chronic renal failure was higher by 121% than in the control group (p<0.001). Concentration of NO in saliva in patients with chronic renal failure after hemodialysis was 121% lower than in the same subjects prior to hemodialysis (p<0.001). A statistically significant negative correlation (r=-0.381, p<0.05) was found between the hemodialysis duration in months and the level of NO in saliva of the patients with chronic renal failure prior to hemodialysis. There was no statistically significant correlation (r=-0.167, NS) between the hemodialysis duration in months and NO levels in saliva of the patients with chronic renal failure after hemodialysis treatment.

Conclusion:

Concentration of NO in saliva of the patients on hemodialysis was statistically significantly higher in relation to NO concentration in the saliva of healthy subjects and after hemodialysis was statistically significantly lower in relation to NO values prior to hemodialysis. Monitoring of changes in NO concentration dynamics in saliva of hemodialysis patients will probably be helpful in monitoring hemodialysis efficacy.

Iron and Oxidative Stress in Parkinson's Disease: An Observational Study of Injury Biomarkers

Parkinson's disease (PD) is characterized by progressive motor impairment attributed to progressive loss of dopaminergic neurons in the substantia nigra (SN) pars compacta. In addition to an accumulation of iron, there is also an increased production of reactive oxygen/nitrogen species (ROS/RNS) and inflammatory markers. These observations suggest that iron dyshomeostasis may be playing a key role in neurodegeneration. However, the mechanisms underlying this metal-associated oxidative stress and neuronal damage have not been fully elucidated. To determine peripheral levels of iron, ferritin, and transferrin in PD patients and its possible relation with oxidative/nitrosative parameters, whilst attempting to identify a profile of peripheral biomarkers in this neurological condition. Forty PD patients and 46 controls were recruited to compare serum levels of iron, ferritin, transferrin, oxidative stress markers (superoxide dismutase (SOD), catalase (CAT), nitrosative stress marker (NOx), thiobarbituric acid reactive substances (TBARS), non-protein thiols (NPSH), advanced oxidation protein products (AOPP), ferric reducing ability of plasma (FRAP) and vitamin C) as well as inflammatory markers (NTPDases, ecto-5’-nucleotidase, adenosine deaminase (ADA), ischemic-modified albumin (IMA) and myeloperoxidase). Iron levels were lower in PD patients, whereas there was no difference in ferritin and transferrin. Oxidative stress (TBARS and AOPP) and inflammatory markers (NTPDases, IMA, and myeloperoxidase) were significantly higher in PD, while antioxidants FRAP, vitamin C, and non-protein thiols were significantly lower in PD. The enzymes SOD, CAT, and ecto-5’-nucleotidase were not different among the groups, although NOx and ADA levels were significantly higher in the controls. Our data corroborate the idea that ROS/RNS production and neuroinflammation may dysregulate iron homeostasis and collaborate to reduce the periphery levels of this ion, contributing to alterations observed in the pathophysiology of PD.

Excessive levels of nitric oxide in rat model of Parkinson's disease induced by rotenone

Systemic rotenone models of Parkinson’s disease (PD) are highly reproducible and may provide evidence on the pathogenesis of PD. In the present study, male Sprague-Dawley rats (1-year-old) were subcutaneously administered with rotenone (1.5 mg/kg/day) for six days and observed for the following three weeks. Compared with the control rats, a significant decrease was observed in the body weight and a marked increase was observed in the areas under the behavioral scoring curves in the rotenone-treated rats. Immunohistochemical staining revealed that the abundance of nigral tyrosine hydroxylase (TH)-positive neurons was markedly reduced following rotenone treatment. ELISA and neurochemical assays demonstrated a significant increase in the levels of nitric oxide (NO) and NO synthase, whereas a marked decrease was observed in the thiol levels in the brains of the rotenone-treated rats. Thus, subacute rotenone treatment was found to induce behavioral deficits and the loss of nigral TH-positive neurons which may be associated with the excessive levels of NO in the rat brains.

Serum insulin-like growth factor-1 and nitric oxide levels in Parkinson's disease

The aim of this study was to investigate the role of circulating growth hormone (GH), insulin growth factor-1 (IGF-1), IGF binding protein-3 (IGFBP-3), and nitric oxide (NO) concentrations in the patients suffering from Parkinson's disease (PD). The study groups were consisted of 25 patients with PD and 25 matched healthy subjects as a control. The NO level of patients in PD group (2.3 +/- 0.4 micromol/L) was significantly lower than that in the control group (2.8 +/- 0.6 micromol/L) (P:.011). Although there were no statistically significant differences in the GH, IGF-1, and IGF BP-3 levels among the two groups, in this preliminary study, we found low NO and mildly elevated IGF-1 levels in the patients with PD. The results may be associated with adaptation or protective mechanisms in the neurodegenerative disease processes such as seen in the PD. Further studies should be carried out to confirm our results.