LINK BETWEEN PROBIOTIC & ORAL HEALTH A REVIEW

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1 wjpmr, 2016,2(5), SJIF Impact Factor: WORLD JOURNAL OF PHARMACEUTICAL AND MEDICAL RESEARCH Review Article ISSN WJPMR LINK BETWEEN PROBIOTIC & ORAL HEALTH A REVIEW Vaibhav Mukand 1, Nisheeth Sharma 2, Shivam Agarwal 3, Siddharth Tevatia 4 * and Vivek Shah 5 1,3,5 Post Graduate Student, Department of Oral & Maxillofacial Surgery& Oral Implantology, Its CDSR. 2 Post Graduate Student, Department of Orthodontic, Its CDSR. 4 Post Graduate Student, Department of Periodontology & Oral Implantology, ITS- CDSR. *Corresponding Author: Dr. Siddharth Tevatia Post Graduate Student, Department of Periodontology & Oral Implantology, Its CDSR, Muradnagar, Ghaziabad Article Received on 14/08/2016 Article Revised on 03/09/2016 Article Accepted on 23/09/2016 ABSTRACT From last three decades probiotic bacteria become popular because of their beneficial effects on human health. The word probiotic come from Greek word pro meaning promoting and biotic meaning life. Probiotic are live bacteria s and yeasts that are good for your health. We always thoughts that bacteria are something which are harmful to our health and that are main etiological factors that cause disease. But our full body contains lots of bacteria, probiotic are the good or helpful bacteria because they help to keep your gut healthy. The purpose of this paper is to review the current credentials on the concept and the possible beneficial properties of probiotic bacteria in the literature, focusing on those available in food. KEYWORD: Bacteria; Micrbo; Lactobacillus; Symbiotic. 1. INTRODUCTION The age-old quote by Hippocrates, Let food be thy medicine and medicine be thy food, is certainly the tenet of today. The market for functional foods that promote health beyond providing basic nutrition, is flourishing. Within the functional foods, is the small but rapidly expanding arena of probiotics. [1] Increase in antibiotic resistant infections due to overuse of antibiotics by physicians and in the livestock industry to improve meat and dairy production, has prompted public and physicians to seek safer ways to treat infections. As public health measures (vaccines, sanitary health care etc) have lessened the worldwide threat of death from infectious diseases during the last few decades, we are confronted by an increase in immune mediated disease states (allergy and autoimmune disease) thought to result from an inadequate exposure to colonizing microorganisms in children because of a more sterile environment (the "hygiene hypothesis") For these reasons,an interest in the use of probiotics and prebiotics to stimulate host defenses and to prevent / treat certain gastrointestinal disease status has developed among physicians and parents caring for child. The primary function of the human gastrointestinal tract has long been considered as digestion and absorption of nutrients and excretion of waste end products. In recent years, however it has become accepted that the gastrointestinal tract fulfills many other functions, which are essential to our well-being. The intestinal tract of humans is host to a vast ecology of microbes and harbors more than 500 identified species that can be cultured and many bacteria that cannot be cultured and properly identified. These bacteria which are necessary for health have the potential to contribute to the development of diseases also by a variety of mechanisms. [2,3] Mucosa of the gastrointestinal tract function as a barrier excluding and eliminating numerous antigens derived from the external environment. [4] The peaceful coexistence of microbes with the host is referred to as host microbe cross-talk, implying a benefit of the microbial presence to the host. [5] Perturbations in the intestinal epithelium can lead to an inflammatory response resulting directly from microbial products that alter the underlying epithelium or allow bacterial and food antigens to stimulate the mucosal immune system. Interactions between intestinal microbes and the host are the subject of intensive ongoing research as these changes influence variety of diseases. There are three general methods by which the intestinal microflora can be altered: administration of antibiotics, prebiotics (dietary components that promote the growth and metabolic activity of beneficial bacteria) & administration of probiotics (beneficial bacteria). The term probiotic, meaning for life, is derived from the Greek language. It was first used by Lilly and Stillwell in 1965 to describe substances secreted by one microorganism which stimulates the growth of another and thus was contrasted with the term antibiotic. [6] The 270

2 term prebiotic was introduced by Gibson and Roberfroid who exchanged pro for pre which means before or for. In contrast, prebiotics are generally defined as non digestible food ingredients that beneficially affect the host by selectively stimulating the growth and or activity of one or a limited number of bacteria in the colon having the potential to improve host health. The role of fermented milk in human diet was known even in Vedic times. But, the scientific interest in this area boosted after the publication of the book entitled The Prolongation of Life by Ellie Metchinkoff [8] in He suggested that people should consume fermented milk containing lactobacilli to prolong their lives. Accelerated aging is because of autointoxication (chronic toxemia), which is due to the toxins produced by gut microflora. Bulgarian peasants who were subjected to the experiments on longevity had consumed large quantities of sour milk. The pathological reaction might be removed and life expectancy could be enhanced by implanting lactic acid bacteria from Bulgarian yogurt. [8] since then, researchers started investigations relating to the role of lactic acid bacteria in human and animal health. 2. COMPOSITION OF PROBIOTICS Probiotics can be bacteria, moulds, yeast. But most probiotics are bacteria. Among bacteria, lactic acid bacteria are more popular. [25] Fuller in 1989 listed the following organisms as species used in probiotic preparation- Lactobacillus bulgaricus, Lactobacillus plantarum, Streptococcus thermophillus, Enterococcus faecium, Enterococcus faecalis, Bifidobacterium species, and Escherichia coli. With the exception of L. bulgaricus and S. Thermophilus, all the other organisms are all intestinal strains. A probiotic may be made out of a single bacterial strain or it may be a consortium as well (may contain any number up to eight strains). The advantage of multiple strain preparations is that they are active against a wide range of conditions and in a wider range of animal species. [25] 2.1 Microorganisms Used as Probiotics [26-27] Bacteria A. Lactobacillus species Lactobacillus acidophilus Lactobacillus bulgaricus Lactobacillus casel Lactobacillus crispatus Lactobacillus fermentum Lactobacillus gasseri Lactobacillus johnsonii Lactobacillus lactis Lactobacillus plantarum Lactobacillus reuteri Lactobacillus rhamnosus B. Bifidobacterium species Bifidobacterium adolescentis Bifidobacterium animalis Bifidobacterium bifidum Bifidobacterium breve Bifidobacterium infantis Bifidobacterium lactis Bifidobacterium longum C) Bacillus cereus D) Enterococcus faecalis E) Enterococcus faeclum F) Escherichia coli Nissie G) Streptococcus thermophilus Yeast Saccharamyces baulardii Lactobacillus species Lactobacillus cultures have been used for hundreds of years to produce a variety of fermented food products including yogurt, cheese, sweet acidophilus milk, and soy sauce. In fact, the long life span of the Balkans and Asians is believed to be attributable in part to the ingestion of fermented milk. Lactobacillus casei decreases intestinal disturbance, balances intestinal bacteria (inhibiting pathogens), lowers fecal enzymes, and impedes superficial bladder cancer. Strains of L. casei reportedly utilize xylitol to produce organic acids such as lactic and acetic acids. These organic acids may in turn have beneficial effects on human glucose and lipid metabolism. Particularly the reduction of serum acetate can reduce the concentration of serum fatty acids, which are an important factor in lowering glucose use by tissues and insulin resistance. Beyond this commercial role, Lactobacilli are important health enhancing residents of the gastro intestinal tract. Ideal ph condition of approximately 5.0 to 7.0 will allow Lactobacilli bacteria to vigorously compete with pathogenic microbes for essential nutrients and attachment sites. Along with numerous mechanisms of actions that are part of probiotics ability to inhibit pathogens, Lactobacilli bacteria actively secrete lactic acid, making the environment around them more suitable for their growth and the exclusion of pathogens. The lactobacillus species help in production of enzymes to digest and metabolize proteins and carbohydrates. They aid in synthesis of vit B and vit K and facilitates breakdown of bile salts. More than 100 species of L. acidophilus, L. brevis, Lactobacilli cultures inhibit the growth of over 25 enteropathogenic organisms and have a direct nutrition enhancing effect. Lactobacilli also inactivate carcinogenic intestinal beta-glucouronidase and nitroreductase. Lactobacillus fermentation products will increase resistance to stress and resultant disease, food palatability, appetite and weight gain. The presence of Lactobacillus species in mammary milk is now believed to be nearly as important as colostrum. Lactobacilli get 271

3 quickly implanted in the digestive tract and exert a protective and beneficial effect. There are three main strains of Lactobacillus species involved in maintaining normal intestinal flora and preventing growth of undesirable bacteria. These include Lactobacillus bulgaricus, Lactobacillus acidophilus and Lactobacillus bifidus. While all three of these organisms are able to tolerate acidity within a ph range of 4.0 to 8.0, L. bulgaricus is not able to withstand the low surface tension created by bile. Therefore, only L. acidophilus and L. bifidus are able to reach the large intestine. The majority of humans become lactase (the enzyme necessary for milk lactose digestion) deficient during the first years of life. The inability to digest lactose causes a decrease in milk product consumption, eliminating a high quality source of protein and calcium. L. acidophilus and L. bifidus participate in the hydrolytic digestion of ingested lactose. Therefore, ingestion of milk products with live Lactobacillus is better tolerated and may actually alleviate malabsorption in lactose intolerant people. In order to increase this lactase activity, cultures must be fully active and added after pasteurization. Probiotics in yogurt also potentiate the production and release of gamma interferon by immunocompetent cells, and may thereby increase immune response. More recently, a study demonstrated that long term consumption of milk caused a signifcant reduction in caries risk. [12,28] Small intestine digestion of lactose is markedly impaired in the premature infant, since fetal lactase does not reach its maximum activity until weeks of gestation. However, by measured breath hydrogen, there was minimal non-digested carbohydrate-derived energy in premature infants fed formulas of either 50% or 100% lactose as the carbohydrate source. This leads to the conclusion that lactose reaching the colon is virtually completely fermented by autochthonous organisms with efficient absorption of the short chain (volatile) fatty acid by-products. This colonic bacterial fermentation may also prevent accumulation of sugars in the colon, which are the principal osmotic stimuli for diarrhea from carbohydrate malabsorption. The quality and quantity of colonic bacterial metabolism may be a crucial determination of whether diarrhoea develops in infants Bifidobacterium bifidum species Like Lactobacilli bacteria, Bifidobacterium bifidum is lactic acid producing, as well as formic acid and acetic acid producing. Additionally, Bifidobacterium bifidum secretes a number of important enzymes including urease and glycosidases as well as various enzymes responsible for cellular repair. Bifdobacterium species are strictly anaerobic and predominate the large intestine. Over 30 species have been identified. The benefts from these include metabolization of lactose, generate lactic ions from lactic acid and synthesize vitamins. They also ferment indigestible carbohydrates and produce benefcial short chain faty acids. They are believed to be benefcial in reducing antibiotic associated diarrhoea and traveller s diarrhoea. They relieve constipation, alleviate infammatory bowel disease and prevent DNA damage. Finally they may prevent or delay the onset of cancers. [29,30] Bifidobacterium is one of the predominant microflora found in infants that are breastfed and has been shown to assist in the prevention of diarrhoea and enteritis in infants. In fact, non-breastfed infants given supplemental Bifidobacterium had fewer incidences of diarrhoea than non-breastfed infants who did not receive any supplements. Bifidobacterium is thought to prevent enteritis and diarrhoea by preventing the onset and shedding of rotavirus, the main cause of such problems in infants Enterococcus faecium species Enterococcus faecium is a gram positive, nonpathogenic, non-hemolytic, and non-proteolytic bacterium, isolated from the healthy gastrointestinal tract of infants. It is a fast growing (divides every 18 minutes), ciliated organism, which makes implantation and colonization extremely successful. The rapid rate at which Enterococcus faecium will grow and multiply enables this probiotic culture to act as an aggressive agent in blocking the growth of pathogenic, toxinproducing microbes. [31] Known as a lactic acid secreting bacteria, Enterococcus faecium is both prophylactic and therapeutic aid for intestinal disorders. It has been used for many years throughout the world in farm animal production. The development of a wide variety of pathogenic agents can be partially or entirely inhibited by E. faecium. Its use as a prophylactic against intestinal disorders has resulted in a decline in the mortality of a wide range of animals. Beneficial Effects of Enterococcus Faecium [31] Fermentation of carbohydrate to lactic acid, thus lowering gastrointestinal ph and discouraging pathogenic growth. An increase in palatability of the food it is found in. Production of antitoxins, which help to neutralize enterotoxins from E.coli. Production of hydrogen peroxide, which has a bactericidal effect on anaerobic microorganisms. Production of metabolites with specific activity against E. coli. Production of antibiotics and bacteriocins, such as acidophylin, acidolin and lactalin. These act against a variety of pathogenic species such as S. proteus, P. aeruginosa, Salmonella, Shigella and Clostridium. Change in the re-dox (oxidation-reduction) potential, thus creating an unsuitable environment for the aerobic pathogenic microorganism. Implants on the mucous surfaces and villi, thus decreasing the coliform count. 272

4 A low sensitivity to most common antibiotics. May be used safely in combination with: Aureomycin, Oxytetracycline, Bacitracin, Lincomycin, Furacin, Carbodox (Mecadox), and Virginiamycin. Proven to be sensitive to Ampicillin, Tetracycline. Inhibition of bacteria that degrade intestinal proteins to non-utilizable forms Streptococcus Thermophillus Species It is primarily used in yogurt production. Beneficial effects are metabolize lactose improve lactose intolerance antimicrobial activity. [30] Saccharomyces Boulardii Species It is a non colonizing lactic acid producing yeast. It prevents antibiotic-associated diarrhoea, C. difficile associated disorders, acute diarrhoea, traveller s diarrhoea in tube fed patients. They are also useful in AIDS related diarrhoea and to prevent relapse of Crohn s disease. Most noted feature is that they secrete proteases and other substances that break bacterial enterotoxins and inhibits their binding to intestinal receptors. They also help in immune function enhancement. Most of the benefcial species enhance vitamin production and reduce serum-cholesterol level and has anticarcinogenic activity. [28,30] 3. RATIONALE The availability of effective and cheap antibiotics in the latter half of the 20th century revolutionized the treatment of infectious diseases and, for developed countries at least, reduced the death rate. The Nobel laureate in immunology, Macfarlane Burnett, stated in 1962 that by the late twentieth century, we can anticipate the virtual elimination of infectious diseases as a significant factor in social life. However, the development of resistance to a range of antibiotics by some important pathogens has raised the possibility of a return to the pre antibiotic dark-ages. Also orally, the widespread use of antibiotics is reflected in the level of resistance in the subgingival microbiota of adult periodontitis patients. [32] These developments have encouraged researchers in various fields of healthcare to develop alternative antimicrobial approaches. The application of health-promoting bacteria for therapeutic purposes is one of the strongest emerging fields in this regard. Antibiotics destroy the harmful bacteria that can cause infection, while also destroying the good bacteria that help to fight infection. Probiotics, on the other hand, repopulate the beneficial bacteria which can help kill pathogenic bacteria and fight against infection. Oral administration of probiotics may also benefit oral health by preventing the growth of harmful microbiota or by modulating mucosal immunity in the oral cavity. [32] According to this approach, a food or food supplement will include both the live cells of the beneficial bacteria and the selective substrate. The idea being that the beneficial bacterial cells can grow quickly and competitively because of the presence of the selective substrate and establish their predominance. 4. MECHANISM OF ACTION The suggested mechanisms of probiotic action on oral health are drawn entirely from gastrointestinal studies. Several mechanisms have been suggested to contribute to the probiotic action on systemic health. [33] They relate to immune modulation, modulation of gut immunological mechanisms, mucin production, down regulation of inflammatory responses, secretion of antimicrobial substances, competition with other flora, including potential pathogens by competitive blocking of adhesion sites at epithelial and mucosal surfaces, and inhibition of epithelial invasion by regulation of intestinal permeability, inhibition of pathogens mucosal adherence and stimulation of immunoglobin A production. [34,35] There is also evidence of production of anti-microbial substances, such as organic acids, hydrogen peroxide and bacteriocins. [35] Probiotics nutritional and health enhancement occurs through The synthesis of certain amino acids, which are directly assimilated (e.g. lysine from specific strains of L. plantarum). Increasing leukocyte and antibody response to disease challenge. A protein-sparing effect - The Lactobacilli primarily use carbohydrates as a growth medium, while the pathogens use primarily protein. By decreasing the pathogenic population, more protein is made available for assimilation. Decreasing intestinal ph increases gastrointestinal tone and motility. Reducing the number of putrefactive bacteria, which prevents bad breath, gas and bloating. Alleviating antibiotic-induced diarrhea, caused by the indiscriminate killing of both good and bad bacteria in the gastrointestinal tract. Lactobacillus can be taken both during and after antibiotic treatment. Reducing the incidence of cold sores by the Herpes Simplex Type I virus. Producing Vitamin B, such as folic acid, niacin, riboflavin, B12, B6 and pantothenic acid, which are biocatalysts in food metabolism and helps fight stress. Lactobacillus species possess anticholesterolemic and antilipidemic factors, which aid in cholesterol reduction Inhibition of Candida albicans, which is the primary yeast responsible for Candidiasis. Studies at the Sloan Kettering Institute for Cancer Research and the University of Nebraska showed 273

5 Lactobacillus to possess a definite anti-tumor activity, and inhibits tumor proliferation. Their applicability to oral health needs further studies. Nevertheless, since the mouth represents the first part of the gastrointestinal tract, there is every reason to believe that at least some probiotic mechanisms may also play a role in that part of the system. It may also be anticipated that resident probiotics could exist in the oral microflora, and that they may function in the complex ecosystem of dental plaque and in the formation and development of oral biofilms in general. Suggested Mechanisms of Probiotics in The Oral Cavity Direct interactions in dental plaque 1) Involvement in binding of oral micro-organisms to proteins (biofilm formation) Antagonistic strains are better adapted to their niche than potential pathogens, and can therefore interfere in disease by passively occupying the niche or actively restricting the adhesion capability of pathogens to surfaces. It has been shown that several bacterial strains, mainly streptococci can hinder colonization of periodontopathogens to hard and soft tissue surfaces in vitro. [36] An alternative way for probiotics to hinder pathogens is the production of biosurfactants that prevent adhesion. Van Hoogmoed et al [37] observed that a biosurfactant generated by S. mitis BA and BMS cells was able to decrease the adhesion of not only S. mutans but also from several periodontopathogens. Interestingly, probiotics have been shown to inhibit adhesion by modifying the protein composition of the binding site. In this aspect, Haukioja et al [17] have shown that certain probiotic strains modify the salivary pellicle protein composition by removing an important adhesion protein, salivary agglutinin gp340, which is necessary for adhesion of S. mutans which resulted in a lower colonization efficiency of S. mutans. 2) Competitive exclusion The competitive exclusion principle, also referred to as Gause s law, states that two species that compete for the same resources cannot stably co-exist. One of the two competitors will always have a slight advantage over the other that leads to extinction of the second competitor or a shift of this species to another niche. The competitive exclusion mechanism used by beneficial bacteria can occur on two levels: hindering the adhesion of pathogenic bacteria OR competing for the same nutrients. 3) Involvement in metabolism of substrates (competing with oral micro-organisms for substrates available) Bacteria can compete for certain essential nutrients or chemicals required for growth and in doing so can inhibit the growth of a pathogen. [38] As an example, P. intermedia utilizes vitamin K to grow. However, this resource may be replaced by progesterone or oestrogen. The levels of progesterone and oestrogen in gingival crevicular fluid are greatly increased during pregnancy. This may explain the transition from a healthy microbiota to the pathogenic one seen during pregnancy gingivitis. Probiotic bacteria, able to out compete periodontopathogens for uptake of these nutrients, could improve oral health. [39] 4) Production of chemicals that inhibit oral bacteria (antimicrobial substances) Probiotic bacteria can produce a diverse range of compounds that act as anti microbial agents such as lactic acid, hydrogen peroxide, bacteriocins and bacteriocin-like inhibitory substances. [18] Short-chain fatty acids such as lactic acids can pass across bacterial cell membranes and acidify the cytoplasm which in turn can inhibit bacterial proliferation. In this respect, Sookkhee et al [40] were able to isolate lactic acid bacteria from healthy oral cavities of Thai volunteers and showed that they had an antimicrobial activity against Porphyromonas gingivalis and Streptococcus mutans. This activity was higher at an acidic ph, indicating that the antimicrobial effect was partly mediated by organic acids like lactic acid. This observation was largely confirmed by Koll-Klais et al [41] who showed higher prevalence of obligatory homofermentative lactobacilli, especially Lactobacillus gasseri, among healthy persons when compared with periodontitis persons. Homofermentative lactobacilli produce higher concentrations of lactic acid in comparison with heterofermentative lactobacilli and induced therefore a more pronounced inhibition of P. gingivalis or Prevotella intermedia. Various in vivo and in vitro studies have shown that production of hydrogen peroxide by probiotic bacterial strains can inhibit the growth of pathogenic bacterial species. [42] In this aspect, Hillman & Shivers [43] showed in a gnotobiotic rat model that the level of A. actinomycetemcomitans colonization in these rats was 45-fold lower in animals infected with a hydrogen peroxide-producing S. sanguis strain when compared with rats infected with a hydrogen peroxide-deficient mutant of this S. sanguis strain. Vanderhoeven & Camp [44] also showed that S. mutans, in co-culture with S. sanguis, was more inhibited when hydrogen peroxide was added to the mixture. Bacteriocins are ribosomally synthesized cationic peptides with a narrow spectrum of antimicrobial activity whereas bacteriocin-like inhibitory substances have a broader spectrum. [45] Several bacteriocins derived from indigenous oral bacteria have been described. [46] S. salivarius produces even two potent bacteriocins, salivaricin types A and B. This strain has been used to prevent dental caries caused by Streptococcus sobrinus and S. mutans. Salivaricin B was effectively used to treat 274

6 halitosis caused by Prevotella spp. and Micromonas micra. [47] Additionally, a bacteriocin from Lactobacillus paracasei HL32 was shown to be able to kill P. gingivalis by changing the cell envelope of the pathogen. [48] Indirect probiotic actions in the oral cavity 1) Modulating systemic immune function Probiotic bacteria or their products (e.g. metabolites, cell wall components and DNA) can be recognized by host cells such as epithelial cells and immune cells. [49] Increased phagocytic capacity of macrophages when challenged with Lactobacillus acidophilus and Lactobacillus casei has been reported. [50] It is known that probiotics can regulate the expression of phagocytosis receptors in the neutrophils of healthy individuals [51] and enhance natural killer cell activity. [52] They have also been shown to modulate the immune response via the adaptive immunity. [53] Only few studies have been conducted to determine whether immune modulation by so called beneficial bacteria also applies to the oral environment. In this aspect, several publications have shown that certain streptococci, such as Streptococcus cristatus, Streptococcus salivarius, Streptococcus mitis and Streptococcus sanguis can attenuate theil)-8 response induced by periodontopathogens such as Fusobacterium nucleatum and Aggregatibacter actionmycetemcomitans on epithelial cells. [54] Recently, Della R et al [55] tested in vivo the immunomodulatory effects of Lactobacillus brevis on periodontal disease. The in vivo use of this probiotic led to a significant decrease in inflammatory markers in the saliva, such as metallo- proteinase and nitric oxide synthase activity, PGE 2 and interferon γ levels. No effect was observed on IgA levels. 2) Effect on local immunity 3) Effect on non-immunologic defence mechanisms. 4) Regulation of mucosal permeability 5) Selection pressure on developing oral microflora towards colonization by less pathogenic species. 5. Prebiotic-Probiotic-Symbiotic Concept. Prebiotic Prebiotic is a non absorbable food component that beneficially stimulates one or more of the gut beneficial microbe groups and thus has a positive effect on human health. Most commonly used prebiotics are: carbohydrate substrates (e.g. Lactulose, galactooligosaccharides, fructooligosaccharides, inulin and its hydrolysates, maltooligosaccharides, starch and dietary fiber) with the ability to promote the components of the normal intestinal microflora which may be beneficial to the host. Complex carbohydrates pass through the small intestine to the lower gut where they become available to some colonic bacteria but are not utilized by majority of the bacteria present in the colon. The main end products of carbohydrate metabolism are short-chained fatty acids, namely acetate, butyrate and propionate, which are further used by the host organism as an energy source. The concept of pre and probiotics is described below in figure1. Prebiotics act as an alternative for probiotics or their cofactors. The immunomodulatory potential of probiotics has introduced new potential therapeutic strategies for combating allergic, infectious and inflammatory conditions. Use of probiotics has the aim of dampening inflammation in the gut, which may involve anti inflammatory mediators. [56] In fact, establishment of indigenous microbiota impacts on healthy immunophysiological regulation in the gut. [57] Aberrant gut microbiota may underlie not only nonspecific GI symptoms or acute infections, but also chronic diseases ranging from allergies to autoimmune and inflammatory diseases. Normalisation of the properties of unbalanced indigenous microflora by specific strains of the healthy gut microflora constitutes the rationale of probiotic therapy. SYMBIOTIC Symbiotic is the word coined for the combined administration of specific prebiotics with probiotics to provide definite health benefits by synergistic action. Fig 1: The probiotic and prebiotic concepts: altering the composition of intestinal microbiota by viable bacterial supplements versus nonabsorbable bacterial substrates. 275

7 6. Vehicles of Probiotic Administration Probiotics in products are provided in one of the four basic ways. 1) A culture concentrate added to a beverage or food (such as a fruit juice). 2) Inoculated into prebiotic fibres. 3) Inoculants into a milk-based food (dairy products such as milk, milk drink, Yogurt drink, cheese, kefir, biodrink). 4) As concentrated and dried cells packaged as dietary supplements (non-dairy product), such as powder, capsule, gelatin tabets. [58] Their efficacy relies on their ability to survive passage through the GI tract and colonize a tissue section. To prevent destruction by gastric acid and intestinal bile salts, some probiotic preparations may be enteric coated or microencapsulated. For colonization to occur, probiotics must contain living, viable organisms and must be ingested on a regular basis in order to maintain effective concentrations. Unfortunately, the manufacturing process may cause living organisms to become nonviable, thus reducing probiotic effectiveness. The quantity, quality and purity of the bacteria or yeast in probiotics can vary among products due to the complexity of quality control with live microorganisms and the lack of universal quality assurance programs. Yli-Knuuttila et al [59] assessed colonization of L. rhamnosus GG (LGG) in the oral cavity of healthy students. After the 14-day trial period, the occurrence of LGG in the oral cavity decreased gradually, indicating that no permanent colonization had occurred and that the oral persistence of LGG was only temporary. However, further colonization studies with larger materials and in different patient groups are still needed. Kang et al [60] reported that W. cibaria efficiently coaggregated with F. nucleatum. Pronase treatment led to additional reduction in co-aggregation between both species, thus indicating the proteinaceus character of the interspecies interaction. Heat-resistant components firmly attached to the cell surface of W. cibaria were responsible for the coaggregation with F. nucleatum. The results of this study clearly showed that the S-layer proteins of the bacterial cell wall may play an important role in the adherence of W. cibaria to the epithelial cells. In a study addressing the survival of bacteria in saliva and their adherence to oral surfaces, Haukioja et al [61] tested the colonization potential of different commercially available probiotics and Lactobacillus and Bifdobacterium strains obtained from the dairy industry. The results focus on several controversial points reflecting mechanisms of colonization in the oral cavity. All test strains demonstrated 24-h survival rates in saliva but had great variations in their binding capacity to the saliva-coated surfaces. Lactobacilli showed better adherence than bifdobacteria. Different Means of Probiotic Administration for Oral Health Purposes. VEHICLE STRAIN OUTCOME Lozenge S. salivarius Reduces oral VSC levels Straw, tablet L. reuteri ATCC S.mutans level reduction Cheese L.rhamnosusGG Reduced risk of high yeast counts and Prorionibacterium JS Hyposalivation Rinse solution W. cibaria Reduction of VSC Capsule, liquid L. sporogenes, L. bifdum, L.bulgaricus,L.thermophilus, L. acidophilus, L. casei, L. rhamnosus Increased salivary counts of lactobacilli without significant decrease in S. mutans counts Yogurt drink L. rhamnosus GG Temporary oral cavity colonization Thus, lactobacilli may compete for the same binding sites on saliva as F. nucleatum isolated from humans and animals worldwide. Lactobacilli isolated from fermented foods were tested for co-aggregation ability with Fusobacterium nucleatum (F. nucleatum) and their attachment to epithelial cells. [60] F.nucleatum plays an important role as a bridge-organism that facilitates the colonization of other bacteria by co-aggregation. [62] It has also been suggested that the co-aggregation abilities of lactobacilli species might enable them to form a barrier that prevents colonization of pathogenic bacteria, due to the production of a microenvironment around these pathogens in which inhibiting substances are generated by Lactobacillus species which explains their lower colonization capacity. [63] This phenomenon indicates that probiotics might affect the formation of oral bioflms and modify resident microfora. [61] 7. DOSAGES Probiotic dosing varies depending on the product and specifc indication. No consensus exists about the minimum number of microorganisms that must be ingested to obtain a benefcial effect. [64] Typically, a probiotic should contain several billion microorganisms to increase the likelihood of adequate gut colonization. [65] Lactobacilli: 1 20 billion colony-forming units per day. S. boulardii: daily doses ranging from mg. [66] Products should be stored according to the manufacturer s recommendations, since some may 276

8 require refrigeration. In addition, preparations may have a limited shelf life, and many pr. 8. CONCLUSION Probiotic agents are living microorganisms belonging to the normal flora, with low or no pathogenicity and a positive effect on the health and well-being of the host. Probiotic therapy uses bacterial interference and immunomodulation in the control of several infectious, inflammatory, and immunologic conditions. Similar to their better known actions in the gastrointestinal tract, probiotics exert their effects in many ways also in the oral cavity. Based on the currently available clinical data, it seems that dietary probiotics do not confer a major risk for oral health. However, the risk of transferring antibiotic resistance from probiotics to virulent microorganisms requires more evaluation. However data on oral probiotics are yet insufficient and it is not known whether the putative probiotic strains could modulate, for example, immune response in the oral cavity as has been suggested to take place in the gut mucosa. In conclusion, probiotics have made their way into oral healthcare and are more likely to be our friend than our enemy. Despite our rapidly increasing knowledge of pathogen host interactions, the role of beneficial bacteria in preventing the emergence of pathogenic species and oral health remains obscure. There is a great need to elucidate the role of the oral beneficial microbiota, to identify beneficial bacteria and to conduct proper large scale studies on the usefulness of probiotics to maintain or improve oral health. Probiotics definitely have a beneficial role in periodontal diseases and halitosis. However further research in this field is mandatory. REFERENCES 1. Suvarna VC and Boby VU, Probiotics in human health: A current assessment. Current science, 2005; 88, 11, 10: Berg RD. The indigenous gastrointestinal microflora. Trends Microbiol., 1996; 4: Guarner F, Malagelada JR.Gut flora in health and disease. Lancet., 2003; 361: Sanderson IR, Walker WA. Uptake and transport of macromolecules by the intestine: possible role in clinical disorders (an update).gastroenterology., 1993; 104: Cebra JJ. Influences of microbiota on intestinal immune system development. Am J Clin Nutr., 1999; 69: Caglar E, Kargul B, Tanboga I. Bacteriotherapy and probiotics role on oral health. Oral Dis., 2005; 11(3): Gibson GR, Roberfroid MB. Dietary modulation of the human colonic microbiota: introducing the concept of prebiotics. J Nutr., 1995: 125: Metchinkoff, E., The Prolongation of Life, Putmans Sons, New York, 1908; Schrezenmeir J, de Vresne M. Probiotics, prebiotics and synbiotics - approaching a definition. Am J Clin Nutr., 2001; 73(2): 361S-4S. 10. Parvez SKA, Malik KA, Ah Kang S, Kim HY. Probiotics and their fermented food products are beneficial for health. J Appl Microbiol., 2006; 100(6): Meurman JH. Probiotics: do they have a role in oral medicine and dentistry? Eur J Ora Sci., 2005; 113(3): Patil Mb, Reddy n. Bacteriotherapy and probiotics in dentistry. KSDJ., 2006; 2: Elisa KB, Scot BS. Regulatory t cells in IBD, current opinion of gastroenterology., 2008; 24: Manisha N, Ashar, Prajapathi JB. Role of probiotic cultures and fermented milk in combating blood cholestrol. Indian J Microbial., 2001; 41: Ishikawa H, Aiba Y, Nakanishi M, Oh-hashi Y, Koga Y. Suppression of periodontal pathogenic bacteria in the saliva of humans by the administration of Lactobacillus salivarius TI J Jpn Soc Periodontol., 2003: 45: Krasse P, Carlsson B, Dahl C, Paulsson A, Nilsson A, Sinkiewicz G. Decreased gum bleeding and reduced gingivitis by the probiotic Lactobacillus reuteri. Swed Dent J., 2005: 30: Haukioja, A., Loimaranta, V. & Tenovuo, J. Probiotic bacteria affect the composition of salivary pellicle and Streptococcal adhesion in vitro. Oral Microbiology and Immunology., 2008; 23: Oelschlaeger, T. A. Mechanisms of probiotic actions - A review. International Journal of Medical Microbiology., 2010; 300: Lilly DM, Stillwell RH. Probiotics: growthpromoting factors produced by microorganisms. Science., 1965: 147: Parker RB. Probiotics, the other half of the antibiotic story. Anim Nutr Health., 1974; 29: Fuller R. Probiotics in man and animals. J Appl Bacteriol., 1989; 66: Havenaar R, Huis Int Veld MJH. Probiotics: a general view. In: Lactic acid bacteria in health and disease, Vol. 1.Amsterdam: Elsevier Applied Science Publishers, Schaafsma G. State of art concerning probiotic strains in milk products. IDF Nutr News Lett., 1996; 5: Naidu AS, Bidlack WR, Clemens RA. Probiotic spectra of lactic acid bacteria (LAB). Crit n Rev Food Sci Nutr., 1999; 39: Senok AC, Ismaeel AY, Botta GA. Probiotics: facts and myths. Clin Microbiol Infect., 2005; 11: Santosa S, Farnworth E, Jones PJ. Probiotics and their potential health claims. Nutr Rev. b., 2006; 64:

9 27. Doron S, Gorbach SL. Probiotics: their role in the treatment and prevention of disease. Expert Rev Anti Infect Ther., 2006; 4: Meurman JH. Probiotics: do they have a role in oral medicine and dentistry? Eur J Oral Sci., 2005; 113(3): Dominique g, Fabienne P, Isabella M, Martini R, Mirreille g. Proposed model: mechanisms of immunomodulation induced by probiotic bacteria. Clinical and Vaccine Immunology., 2007; 14: Nicole MR, Martjjn BK. Efects of probiotic bacteria on diarrhea, lipid metabolism & carcinogenesis;a review of papers published between American J of Clinc Nutrition., 2000; 71: Rationale for Probiotic supplementation, 2006 Wysong corporation. 32. Van Winkelhoff AJ, Herrera GD, Winkel EG, Dellemijn Kippuw N, Vandenbrouck Grauls CM, Sanz M. Antimicrobial resistance in the subgingival microflora in patients with adult periodontitis. A comparison between the Netherlands and Spain. J Clin Periodontol., 2000; 27: Meurman JH. Probiotics: do they have a role in oral medicine and dentistry? Eur J Oral Sci., 2005; 113: Saavedra JM, Abi-Hanna A, Moore N, Yolken RH. Long-term consumption of infant formulas containing live probiotic bacteria: tolerance and safety. Am J Clin Nutr., 2004; 79(2): Miles L. Are probiotics benefi cial for health? Nutr Bull., 2007; 32(1): Teughels, W., Haake, S. K., Sliepen, I., Pauwels, M., Van Eldere, J., Cassiman, J. J. & Quirynen, M. Bacteria interfere with A. actinomycetemcomitans colonization. Journal of Dental Research., 2007a; 86: Van Hoogmoed, C. G., van der Kuijl-Booij, M., Vander Mei, H. C. & Busscher, H. J. Inhibition of Streptococcus mutans NS adhesion to glass with and without a salivary conditioning film by biosurfactant-releasing Streptococcus mitis strains. Applied and Environmental Microbiology., 2000; 66: Elli, M., Zink, R., Rytz, A., Reniero, R. & Morelli, L. Iron requirement of Lactobacillus spp. In completely chemically defined growth media. Journal of Applied Microbiology., 2000; 88: Smith, V. H. & Pippin, D. J. Implications of resource-ratio theory for oral microbial ecology. European Journal of Oral Sciences., 1998; 106: Sookkhee, S., Chulasiri, M. & Prachyabrued, W. Lactic acid bacteria from healthy oral cavity of Thai volunteers: inhibition of oral pathogens. Journal of Applied Microbiology., 2001; 90: Koll-Klais, P., Mandar, R., Leibur, E., Marcotte, H., Hammarstrom, L. & Mikelsaar, M. Oral lactobacilli in chronic periodontitis and periodontal health: species composition and antimicrobial activity. Oral Microbiology and Immunology., 2005; 20: Tompkins, G. R. & Tagg, J. R. Incidence and characterization of anti-microbial effects produced by Actinomyces viscosus and Actinomyces naeslundii. Journal of Dental Research., 1986; 65: Hillman, J. D. & Shivers, M. Interaction between wild-type, mutant and revertant forms of the bacterium Streptococcus sanguis and the bacterium Actinobacillus actinomycetemcomitans in vitro and in the gnotobiotic rat. Archives of Oral Biology., 1988; 33: Vanderhoeven, J. S. & Camp, P. J. M. Mixed continuous cultures of Streptococcus mutans with Streptococcus sanguis or with Streptococcus oralis as a model to study the ecological effects of the lactoperoxidase system. Caries Research., 1993; 27: Cintas, L. M., Casaus, M. P., Herranz, C., Nes, I. F. & Hernandez, P. E. Review: bacteriocins of lactic acid bacteria. Food Science and Technology International., 2001; 7: Teanpaisan, R., Baxter, A. M. & Douglas, C. W. I. Production and sensitivity of bacteriocin like activity among Porphyromonas gingivalis, Prevotella intermedia and Pr-nigrescens strains isolated from periodontal sites. Journal of Medical Microbiology., 1998; 47: Balakrishnan, M., Simmonds, R. S. & Tagg, J. R. Dental caries is a preventable infectious disease. Australian Dental Journal., 2000; 45: Pangsomboon, K., Kaewnopparat, S., Pitakpornpreecha, T. & Srichana, T. Antibacterial activity of a bacteriocin from Lactobacillus paracasei HL32 against Porphyromonas gingivalis. Archives of Oral Biology., 2006; 51: Delcenserie, V., Martel, D., Lamoureux, M., Amiot, J., Boutin, Y. & Roy, D. Immunomodulatory effects of probiotics in the intestinal tract. Current Issues in Molecular Biology., 2008; 10: Perdigon, G., Maldonado, G. C., Valdez, J. C. & Medici, M. Interaction of lactic acid bacteria with the gut immune system. European Journal of Clinical Nutrition., 2002; 56(4): S21 S Pelto, L., Isolauri, E., Lilius, E. M., Nuutila, J. & Salminen, S. Probiotic bacteria down-regulate the milk-induced inflammatory response in milkhypersensitive subjects but have an immunostimulatory effect in healthy subjects. Cinical and Experimental Allergy: Journal of the British Society of Allergy and Clinical Immunology., 1998; 28: Takeda, K., Suzuki, T., Shimada, S. I., Shida, K., Nanno, M. & Okumura, K. Interleukin-12 is involved in the enhancement of human natural killer cell activity by Lactobacillus casei Shirota. Clinical and Experimental Immunology., 2006; 146:

10 53. Link-Amster, H., Rochat, F., Saudan, K. Y., Mignot, O. & Aeschlimann, J. M. Modulation of a specific humoral immune response and changes in intestinal flora mediated through fermented milk intake. Fems Immunology and Medical Microbiology., 1994; 10: Cosseau, C., Devine, D. A., Dullaghan, E., Gardy, J. L., Chikatamarla, A., Gellatly, S., Yu, L. L., Pistolic, J., Falsafi, R., Tagg, J. & Hancock, R. E. W. The commensal Streptococcus salivarius K12 downregulates the innate immune responses of human epithelial cells and promotes host-microbe homeostasis. Infection and Immunity., 2008; 76: Della Riccia, D. N., Bizzini, F., Perilli, M. G., Polimeni, A., Trinchieri, V., Amicosante, G. & Cifone, M. G. Anti-inflammatory effects of Lactobacillus brevis (CD2) on periodontal disease. Oral Diseases., 2007; 13: Zhang G, Ghosh S. Toll-like receptor-mediated NFkappaB activation: a phylogenetically conserved paradigm in innate immunity. J Clin Invest., 2001; 107: Rautava S, Ruuskanen O, Ouwehand A,Salminen S, Isolauri E. The hygiene hypothesis of atopic disease an extended version. J Pediatr Gastroenterol Nutr., 2004; 38: Persson RG. Immune responses and vaccination against periodontal infections. J Clin Periodontol., 2005; 32(6): Yli-Knuuttila H, Sna ll, KariK, Meurman JH.Colonization of Lactobacillus rhamnosus GG in the oral cavity. Oral Microbiol Immunol., 2006; 21: Kang MS,Na HS,Oh LS. Coaggregation ability of Weissella cibaria isolates with Fusobacterium nucleatum and their adhesiveness to epithelial cells. FEMS Microbiol Lett., 2005; 253: Haukioja A, Yli-Knuuttila H, Liomaranta Vet al. Oral adhesion and survival of probiotic and other lactobacilli and bifdobacteria in vitro. Oral Micorbiol Immunol., 2006; 21: Kolenbrander PE. Oral microbial communities: bioflms, interactions, and genetic systems. Annu Rev Microbiol., 2000; 54: Boris S, Suarez JE, BarbesC. Characterization of the aggregation promoting factor from Lacobacillus gasseri, a vaginal isolate. J Appl Microbiol., 1997; 83: Farnworth ER. The evidence to support health claims for probiotics. J Nutr., 2008; 138(suppl): 1250S-4S. 65. Cremonini F, Di Caro S, Nista EC et al. Metaanalysis: the effect of probiotic administration on antibiotic-associated diarrhoea. Aliment Pharmacol Ther., 2002; 16: Kligler B, Cohrssen A. Probiotics. Am Fam Physician., 2008; 78: Ouwehand AC, Kirjavainen PV, Shor C, Salminen S. Probiotics: mechanisms and established effects. Int Dairy., 1999; J 9: