The genital system of women has been colonized by various species of microorganisms since the beginning of life. In the postnatal period, the method of birth is important; when a child is born naturally, passing the female genital tract, it acquires bacteria present in the mother’s vagina, and when through the cesarean section, the child’s organism is first colonized by the mother’s skin microbiota and hospital strains. In female newborns during the first days after the natural birth, the presence of
1. Introduction. 2. Microbiome of the baby in the prenatal and postnatal period. 3.
- vaginal probiotics
- genital system of women
- probiotyki dopochwowe
- układ płciowy kobiet
The human body is a unique living environment for many microorganisms characterized by a large diversity of species and genera. Bacteria, fungi, archaea and viruses colonizing the human body are called a microbiota . They are found both on the skin surface and in the entire digestive system, from the oral cavity to the anus, in the upper respiratory tract and the urogenital system. However, most of them inhabit our digestive tract, including their greatest abundance in the large intestine, where in 1 ml of the content there are on average 1012 microbial cells [25, 58]. Currently, the term microbiome refers to the set of genomes of archaea, commensal, symbiotic and pathogenic bacteria and fungi as well as viruses in the human environment. Clarification of this term became possible thanks to the development of molecular biology and genetic engineering, in particular metagenomic sequencing [32, 50, 58]. Acquiring knowledge of the microbiome revealed the presence of many microorganisms that had previously been unknown . The first comprehensive studies of the human microbiome were launched in 2007 by implementing the international Human Microbiome Project (HMP). The project mentioned above concerned microorganisms whose discovery was based on their genomic nucleotide sequences (metagenomes), nucleotide sequences of messenger RNA (metatranscriptome), protein synthesis (metaproteome) and determination of metabolic products (metabolome) . It is reported that the weight of an adult human’s microbiota is approx. 1-1.5 kg [35, 62]. Microorganisms are particularly abundant and multiply in the places of human body secretions and fluids, such as saliva, sweat, urine, tallow, runny nose, vaginal mucus and blood. Among them are microorganisms providing metabolites necessary for the proper functioning of the organism and pathogens, which cause dysbiosis in the human organism, often causing infections, inflammations, viral, bacterial or fungal diseases.
The female vagina is a characteristic microenvironment of the human body. The species diversity of the vaginal microbiota depends on many factors, such as: woman’s age, place of residence (climatic zone), quality and frequency of hygienic procedures, medications applied, e.g. antibiotics, steroids, immunosuppressants or level of hormones, mainly estrogens in the female organism . The predominant group of bacteria colonizing the vagina of healthy women are the rods of
Until recently, it was thought that the intrauterine environment of a child’s life is sterile. However, modern microbiological and genetic tests confirm the existence of microorganisms in a child already in the prenatal period. The source of these microorganisms is the mother’s organism, and her health condition has a big impact on their quality.
During pregnancy, the female body undergoes numerous changes at the hormonal, immunological and metabolic level, necessary for the normal growth and development of the child in the prenatal period . During this time, the levels of secreted hormones: progesterone and estrogens increase rapidly, and complex changes modulating the immune system, protecting the mother and child from infections are observed.
During the prenatal development of the child, the presence of bacteria has been demonstrated in the placenta, amniotic fluid and umbilical cord blood. It was found that the bacterial populations present in the placenta and amniotic fluid are similar and exhibit little diversification. The type
The analysis of the composition of the bacteria species identified in meconium, placenta and amniotic fluid showed a high similarity to the species composition of bacteria found in the mouth of mothers. It has been observed that some oral cavity and gum diseases in pregnant mothers increase the risk of premature labour . Therefore, it is important to care for hygiene and prevent periodontal diseases in this group of women. Another reason for the translocation of bacteria into the uterine cavity in pregnant women are prolonged vaginal infections. Aerobic, anaerobic bacteria and yeast-like fungi have also been identified in the uterine cervix. In addition to commensal bacteria of the genus
Among the postnatal factors affecting the microbiome of the newborn, the following are distinguished: the type of delivery (natural or caesarean section), diet (breastfeeding or modified milk), hygiene (sufficient or excessive) and the use or not of the antibiotic therapy or other medications in the first days of the child’s life, e.g. steroids, modifying the composition of the microflora. During natural delivery, the neonate, passing through the mother’s birth canal, has contact with the microflora derived from her vagina, mainly with the lactic fermentation rods of the genus
Over time, the differences in the microbiomes of infants born in a different way gradually diminish, however, the first microorganisms acquired during labour can persist up to approx. 6-24 month of life [8, 34, 39]. After delivery, the composition of the infant’s microbiome is shaped depending on the type of feeding. The microbiological profile of the naturally fed infant’s microbiome abounds in various microbial species, including lactic acid bacteria of the genera
The mucous membrane of the female vagina is the site where numerous bacteria occur. So far, 37 genera have been identified, i.e.:
The most abundant amongst them are Gram-positive lactobacilli of the genus
To date, 25 species of
The structure, size and composition of vaginal microbiota depends on genetic and environmental factors and correlates with the geographical place of residence of women, individual predispositions for colonization and hormone levels [24, 63]. It is observed that the abundance of the rods of
Currently, many strains isolated from the vagina of women living in Europe, America, Asia and Africa have been tested (Table I). Among the species being dominant in the vaginal microbiota of Polish women, the following prevail:
Bacteria of the genus
|Poland/Europe||[19, 56, 68, 69]|
|United States/North America||[4, 75]|
It has also found that the microbiome of female genital tract during the nine months of pregnancy is subject to significant microbiological changes. It becomes stable and less diverse in terms of species composition, with predominance of the bacteria of the genus
Based on the studies of the vaginal microbiota of healthy women in reproductive age from all over the world, the microorganisms occurring in the vagina are classified in V CST (Community State Types) groups . The CST types distinguished: I, II, III and V, are dominated by the following lactic fermentation bacteria:
Percentage of five types of CST
|Ethnic group/ CST %||Asians/Asian||Caucasian/White||Black African/Black||Latino/Hispanic|
It was also observed that the number of
The reduction in the abundance of beta-lactam antibiotics: natural, isoxazole and semi-synthetic penicillins, cephalosporins, carbapenems, monobactams, macrolides, lincosamides, fusidic acid; peptide antibiotics, containing in their composition bacteriocins, i.e. : gramatacin, tirodacin, bacitracin, viomycin, polymyxin; glycopeptide: vancomycin and teicoplanin; semi-synthetic lipopeptides, e.g.: daptomycin.
beta-lactam antibiotics: natural, isoxazole and semi-synthetic penicillins, cephalosporins, carbapenems, monobactams, macrolides, lincosamides, fusidic acid;
peptide antibiotics, containing in their composition bacteriocins, i.e. : gramatacin, tirodacin, bacitracin, viomycin, polymyxin;
glycopeptide: vancomycin and teicoplanin;
semi-synthetic lipopeptides, e.g.: daptomycin.
The vaginal microbiota is also influenced by the use of hormonal contraceptives, containing low doses of estrogen, which blocks ovulation and maturation of the endometrium. Thus, the level of glycogen in the vagina is low, resulting in a reduction in the number of
The term mycobiome is defined as the sum of genomes and genes belonging to the fungi which inhabit a specific biological niches. The female genital tract, and in particular the vagina, is a specific microenvironment for fungi, to which considerable attention has been paid in the last few years. Molecular technique – NGS sequencing (Next Generation Sequencing) and bioinformatics tools play an important role in understanding the diversity of fungi and are useful in identifying microorganisms and providing a new insight into fungal ecology. Initial studies were based on the techniques of culturing the material obtained through swabs from healthy volunteers or diabetics, teenagers or pregnant women. Fungi were detected in 20–60% of trials . Among them, the yeasts of the genera
Yeasts enter the human organism from the natural environment and can be transferred to newborns during labour, colonizing specific human body niches. Ward
There is more and more evidence indicating that estrogens have a positive effect on the colonization of the vaginal mucosa and subsequent infection caused by
The initial adhesion of yeast to epithelial cells is regulated by hydrophobic interactions between surfaces. The attachment of yeast to the epithelial cell receptors is mediated by adhesion proteins [11, 14]. High capacity of yeasts for adhesion to epithelial cells obtained from women suffering from recurrent candidiasis of vulva and vagina (VVC – VulvoVaginal Candidiasis) has been demonstrated. It is estimated that 3 out of 4 women have been infected with candidiasis at least once in their lifetime, and 20% of healthy women may also be asymptomatic carriers that have been infected with this microorganism in commensal interactions. There exists a view whereby the predispositions for being colonised by
An important issue is an interaction between the bacteria found in the vagina, mainly the rods of
Characteristics of the human mycobiome is important for the development of diagnostics and preventive measures in fungal diseases, including vaginal candidiasis.
Female vaginal microbiota disorders are most often caused by a decrease in the number of lactobacilli to the advantage of pathogenic microorganisms. This results in various types of infections, i.e. bacterial vaginosis and vaginal candidiasis [7, 57, 60]. Vaginal homeostasis disorders are caused by antibiotics, steroid and immunosuppressive drugs, as well as hormonal and barrier contraceptive agents such as condoms, caps and vaginal diaphragms which damages the vaginal epithelium. Other factors with poorly understood mechanism of influencing the vaginal microbiota are: poor hygiene, use of underwear made of synthetic materials, vaginal irrigation, weakening of the immune system as a result of systemic infection or chronic diseases or stress, use of tampons, sexual intercourse or even swimming in a pool during which some rods of
Among the basic requirements for vaginal probiotics the following are listed: being derived from the urogenital system of young women; accurate genetic, biochemical and morphological identification of the strain; clinically proven ability to colonize the female vagina; antagonistic activity against pathogenic bacteria causing infections of the urogenital system; strong adherence to the vaginal epithelium; confirmed reduction of the adhesion of pathogens to the vaginal epithelium; specific resistance to antibiotics for a given species .
being derived from the urogenital system of young women;
accurate genetic, biochemical and morphological identification of the strain;
clinically proven ability to colonize the female vagina;
antagonistic activity against pathogenic bacteria causing infections of the urogenital system;
strong adherence to the vaginal epithelium;
confirmed reduction of the adhesion of pathogens to the vaginal epithelium;
specific resistance to antibiotics for a given species .
It has been demonstrated that the use of the
Polish studies have demonstrated that oral administration of three specific strains:
Vaginal probiotics available on the pharmaceutical market are in the form of freeze-dried cellular biomass immobilized in hard cellulose or gelatine capsules. The frequency of their application depends on the severity of infection resulting from vaginal microbiota disorders. They can colonize the vagina or stay there long enough to cause the restoration of native, natural microbiota. For this purpose, they must produce L (+) lactic acid in an amount of more than 50% of the total amount of acid produced and possibly other organic acids, such as acetic, formic, propionic, benzoic or mevalonic acid. They should have the ability to adhere to the vaginal epithelium, which requires testing their hydrophobic properties, surface charge, surface structure and affinity for the epithelial cell receptors.
Knowledge and understanding of the functioning of the female reproductive system microbiota is important in the treatment and prevention of vaginal infection. The more so because they are often chronic and difficult to treat, which constitutes a contemporary challenge in urology and gynaecology. In particular, vaginosis and candidiasis which occur in pregnant women require treatment due to the risk of miscarriages and intrauterine infections. More and more knowledge about the role of probiotic bacteria in the treatment of vaginal infections allows the search for new, effective strains. It is important that they have GRAS (generally recognized as safe) status, i.e. they are non-pathogenic and do not produce toxic, carcinogenic, teratogenic and mutagenic substances. In addition, they should survive the technological process and storage period in dry and refrigerated conditions for 12 to 24 months. All the more so because during production, the bacteria are most often subjected to the freeze-drying process (lyophilization), which allows for obtaining permanent preparations which preserve their viability. In addition, a probiotic preparation which is a medicine should be manufactured in accordance with good manufacturing practice (GMP) and be appropriately labelled. There is a great need to compose new vaginal probiotics on the Polish market, which is deficient in preparations based on native
Percentage of five types of CST Lactobacillus bacteria in four ethnic groups of women
|Ethnic group/ CST %||Asians/Asian||Caucasian/White||Black African/Black||Latino/Hispanic|
Bacteria of the genus Lactobacillus isolated from the female vagina in various geographical regions
|United States/North America||[|