Crevicular fluid iron changes in treated and untreated periodontally diseased sites

Nutritional factors influencing microbiota-mediated colonization resistance of the oral cavity: A literature review

The oral cavity is a key biocenosis for many distinct microbial communities that interact with both the external environment and internal body systems. The oral microbiota is a vital part of the human microbiome. It has been developed through mutual interactions among the environment, host physiological state, and microbial community composition. Indigenious microbiota of the oral cavity is one of the factors that prevent adhesion and invasion of pathogens on the mucous membrane, i.e., the development of the infectious process and thereby participating in the implementation of one of the mechanisms of local immunity-colonization resistance. The balance between bacterial symbiosis, microbial virulence, and host resistance ensures the integrity of the oral cavity. In this review we have tried to address how nutritional factors influence integrity of the oral indigenous microbiota and its involvement in colonization resistance.

A comparative evaluation of the micronutrient profile in the serum of diabetes mellitus Type II patients and healthy individuals with periodontitis

Background

Micronutrients play an important part in metabolism and maintenance of tissue function the maintenance of the integrity and vitality of the periodontal tissues depends on the availability of adequate nutrients, and it is possible that deficiencies can produce pathological alterations in the periodontal tissues. However, the association between nutritional factors and periodontal health is not fully understood. The essential micronutrients for maintaining health include zinc, copper, selenium, and iron. These micronutrients are required for a variety of biomolecules to maintain the normal structure, function, and proliferation of cells and also immune functions. Periodontal disease and diabetes mellitus (DM) are considered to have a bidirectional relationship, and periodontitis is recognized as the 6^th major complication of DM. The number of studies on the role of micronutrients with regard to periodontal disease is limited.

Aims

This study aims to evaluate the role of micronutrients-zinc, copper, selenium, and iron, in the serum of chronic periodontitis patients and chronic periodontitis with DM Type II patients, to see whether they can serve as potential markers for chronic periodontitis and also to assess whether periodontitis can have systemic effects.

Materials and Methods

A volume of 5 ml of venous blood was collected from each of the study participants, from the antecubital vein. The blood was then centrifuged and stored at -20°C before being analyzed. Zinc, copper, and selenium were estimated by the atomic absorption spectrophotometry, bathophenanthroline method was used to estimate iron.

Statistical Analysis

It was carried out using Student's t-test and analysis of variance. The honestly significant difference Tukey test and Pearson's correlation was also used.

Results

The mean serum zinc levels were significantly higher in healthy controls as compared to Periodontitis and Periodontitis with DM type II. The mean serum copper levels were significantly higher in Periodontitis with diabetes as compared to controls and periodontitis. Serum selenium levels were significantly higher in controls as compared to periodontitis with diabetes. The mean serum iron levels were significantly higher in periodontitis with diabetes. The Zinc: Copper (Zn: Cu) ratio was found to be significant for the periodontitis with diabetes group.

Conclusion

The results obtained from this study suggests that the serum levels of micronutrients Zn and Se were decreased and levels of Cu and Fe are increased in chronic periodontitis as compared to healthy control. There was a potentiated difference in the values in patients with DM Type II. The results show that the levels of these micronutrients can be used as effective biomarkers for chronic periodontitis and that periodontitis has systemic manifestations.

Periodontal status and serum biomarker levels in HFE haemochromatosis patients. A case-series study

AIM

To investigate the association between periodontal status and serum biomarkers in patients with HFE haemochromatosis.

MATERIAL AND METHODS

This clinical case series included 84 HFE-C282Y homozygous patients. Periodontal evaluation was performed using clinical attachment level, probing depth, gingival bleeding index, visible plaque index and gingival index. Serum markers of iron metabolism were collected from medical records. The relationship between serum biomarkers of iron burden and the severity of periodontitis was investigated.

RESULTS

The study population consisted of 47 men and 37 women, routinely treated in the Unit of Hepatology, University Hospital, Rennes. All patients presented with periodontitis (mild: n = 1, moderate: n = 37 and severe: n = 46). There was a positive association between transferrin saturation >45% and the severity of periodontitis (adjusted odds ratio = 5.49, p = .002).

CONCLUSION

Severe periodontitis is associated with the severity of iron burden in patients with HFE-related hereditary haemochromatosis. Dental examination should be included in the initial assessment of all these patients.

Do probiotics offer opportunities to manipulate the periodontal oral microbiota?

BACKGROUND

As in other fields of healthcare, probiotics have been introduced for prevention and treatment of periodontal diseases.

OBJECTIVE

This review was initiated to explore whether the use of probiotics can influence the periodontal microbiota and periodontal health.

MATERIALS AND METHODS

Literature on the mode of action of oral probiotics was reviewed and a systematic review was performed on the microbiological and clinical effects of oral probiotics on periodontal health.

RESULTS

Three animal and 11 in vivo human studies were retrieved. Six studies reported on microbiological effects whereas eight studies report on clinical effects. Seven studies were performed on healthy or gingivitis patients and four studies on periodontitis patients. Many of the retrieved studies are pilot in nature and with low quality. The high degree of heterogeneity between studies hampered analysis.

CONCLUSION

Taking into consideration all limitations, the currently available data indicate an effect of probiotics on the oral microbiota and a more limited effect on clinical periodontal outcome measures. However, there is an urgent need for properly conducted clinical trials where probiotics are used as adjuncts to standard periodontal care, similar to antibiotics, using probiotic strains with, at least at an in vitro level, proven periodontal probiotic effects.

Relationship between iron-deficiency anemia and periodontal status in female patients

BACKGROUND

The aim of this study was to evaluate the periodontal status of patients with iron-deficiency anemia (IDA) and the correlation of changes in serum and gingival crevicular fluid (GCF) ferritin levels after periodontal therapy.

METHODS

Nineteen female patients with anemic hematologic values were classified as group A, and 20 healthy females with normal hematologic values were classified as group B. After group A was recruited, group B was enrolled with patients who had similar gingival indices as group A. At baseline and the 3-month follow-up visit, clinical periodontal indices and hematologic parameters were recorded, and GCF samples were taken. All patients received an oral hygiene-improvement session followed by scaling, and sites with >4-mm probing depths received root planing. At the 3-month follow-up visit, all measurements and analyses were repeated.

RESULTS

During the follow-up period, all clinical indices decreased in both groups (P <0.05), but the gingival index in group A did not change. The GCF ferritin concentration showed statistically significant decreases (P <0.05), but total amounts of ferritin in GCF did not change. No significant correlation was found between serum and GCF ferritin levels.

CONCLUSION

The findings of this study showed that changes in serum ferritin levels did not correlate with the GCF ferritin levels, and IDA was not a direct risk factor for periodontal diseases.

Acquisition of iron from human transferrin by Porphyromonas gingivalis: a role for Arg- and Lys-gingipain activities

Porphyromonas gingivalis, a key causative agent of adult periodontitis, is known to produce a variety of virulence factors including proteases. The aim of this study was to evaluate the participation of Arg- and Lys-gingipain activities of P. gingivalis in the acquisition of iron from human transferrin and its subsequent utilization in growth. Iron-saturated transferrin was found to support the long-term growth of P. gingivalis. Our results indicated that P. gingivalis does not produce siderophore and does not possess ferric reductase and transferrin-binding activities. Incubating transferrin with P. gingivalis resulted in degradation of the protein, a step that may be critical for the acquisition of iron from transferrin. Spontaneous and site-directed mutants of P. gingivalis deficient in one or several proteases were used to demonstrate the key role of specific enzymes in degradation of transferrin and subsequent utilization for growth. The lack of both Arg- and Lys-gingipain activities (mutants M1 and KDP128) was associated with an absence of degradation of transferrin and the incapacity of bacteria to grow in the presence of transferrin as the sole source of iron. It was also found that the Lys-gingipain activity is more critical than the Arg-gingipain activity since the mutant KDP112 (deficient in Arg-gingipain A and B) could grow whereas the mutant KDP129 (deficient in Lys-gingipain) could not. The fact that growth of mutant KDP112 was associated with a lower final optical density and a generation time much longer compared with the parent strain suggests that the Arg-gingipain activity also participates in the acquisition of iron from transferrin. Selected inhibitors of cysteine proteases (TLCK, leupeptin and cathepsin B inhibitor II) were tested for their capacity to reduce or inhibit the growth of P. gingivalis under different iron conditions. All three inhibitors were found to completely inhibit growth of strain ATCC 33277 in a medium supplemented with transferrin as the source of iron. The inhibitors had no effects when the bacteria were grown in a medium containing hemin instead of transferrin. The ability of P. gingivalis to cleave transferrin may be an important mechanism for the acquisition of iron from this protein during periodontitis.

Iron-chelating activity of tetracyclines and its impact on the susceptibility of Actinobacillus actinomycetemcomitans to these antibiotics

Three tetracyclines (tetracycline, doxycycline, and minocycline) were found to possess iron-chelating activity in a colorimetric siderophore assay. Determination of MICs indicated that the activity of doxycycline against the periodontopathogen Actinobacillus actinomycetemcomitans was only slightly influenced by the presence of an excess of iron that likely saturates the antibiotic. On the other hand, the MICs of doxycycline and minocycline were significantly lower for A. actinomycetemcomitans cultivated under iron-poor conditions than under iron-rich conditions.

Membrane protein expression by Actinobacillus actinomycetemcomitans in response to iron availability

Iron-limited growth conditions under anaerobiosis were established for Actinobacillus actinomycetemcomitans strains Y4, JP2, and 75 by use of the ferrous ion chelator 2,2'-dipyridyl. Growth inhibition was reversible with both ferrous and ferric iron sources. Sarcosyl-insoluble membrane fractions of iron-stressed anaerobic A. actinomycetemcomitans cultures revealed a similar iron-repressible protein of approximately 70 kDa in A. actinomycetemcomitans strains Y4, JP2, and 75. This 70-kDa protein was recognized by serum from localized juvenile periodontitis patients and a periodontally healthy subject. This suggested that the 70-kDa iron-repressible protein may be expressed in vivo. When A. actinomycetemcomitans was grown under aerobic conditions, the ferric iron chelator, ethylenediamine di(o-hydroxyphenylacetic acid) (EDDA) was utilized for growth limitation. EDDA inhibition was reversible in strain Y4 with ferrous and ferric iron sources. An iron-repressible protein of approximately 70 kDa was also noted in iron-stressed aerobic cultures. The 70-kDa protein may be involved in iron transport by A. actinomycetemcomitans. Preliminary experiments were performed to examine potential iron transport systems for A. actinomycetemcomitans. Production of the two most common chemical types of siderophore was not detected in A. actinomycetemcomitans culture supernatants. Iron-starved A. actinomycetemcomitans cells did not bind transferrin or lactoferrin in a dot blot assay.

Host response tests for diagnosing periodontal diseases

Extensive data collected over the past decade demonstrate clearly that disease-active and disease-inactive periodontal pockets exist, disease progression is infrequent and episodic, and most progression occurs in a small proportion of highly susceptible individuals. Furthermore, traditionally used diagnostic procedures do not identify susceptible individuals nor distinguish between disease-active and disease-inactive periodontal sites. New diagnostic tests based on host response factors that will aid in resolving these problems appear to be possible. Sources of material for use in such tests include gingival crevicular fluid (GCF), blood cells, and blood serum. Of these, components in GCF are most promising, at least in the immediate future. Although more than 40 GCF components have been studied, efforts that attempt to relate the presence and amount of a given component to an independent measure of active disease are very few in number. As a consequence, we do not yet know the potential for most GCF components as the basis of diagnostic tests. Those components that have been documented to associate with active disease as measured by attachment loss of 2 mm or greater include alkaline phosphatase, beta-glucuronidase, prostaglandin-E2, aspartate aminotransferase, and IgG4 antibody subclass. Even in these cases, the data base is small and additional clinical studies are needed to document claims. At the present time, tests based on beta-glucuronidase, nonspecific neutral proteases, and aspartate aminotransferase are being commercialized. One test has received FDA approval. Tests based on blood cells have limited application for patients with adult periodontitis, but are useful for patients with early-onset forms of periodontitis. An abnormality in the leukocyte adherence molecules on the surfaces of neutrophils is diagnostic for generalized prepubertal periodontitis, and defects in chemotactic receptor numbers and in a surface molecule designated as GP110 are found on the neutrophils of most but not all localized juvenile periodontitis patients. Recent data indicate that enhanced unstimulated or stimulated release of PGE2 and Interleukin-1 by peripheral blood monocytes may be an indicator of susceptibility to severe periodontitis. Assessment of the humoral immune response as reflected by serum antibodies to antigens of periodontopathic bacteria shows little promise as the basis for tests diagnostic of site-specific disease activity. However, the capacity of an individual to mount an IgG2 subclass response to carbohydrate antigens may have potential as an indicator of disease susceptibility.