Administration of oral and vaginal prebiotic lactoferrin for a woman with a refractory vaginitis recurring preterm delivery: Appearance of lactobacillus in vaginal flora followed by term delivery

Review, role of lactoferrin in preventing preterm delivery

Prevention of preterm birth (PTB) is a global challenge and is one of the most important issues to be addressed in perinatal care. The hypothesis that ascending lower genital infection leads to PTB has been tested in numerous in vitro and in vivo studies. For patients with intractable vaginitis or high-risk patients with successive PTBs, mainly due to intra-uterine infection, the vaginal flora is enhanced to increase systemic immunity and locally propagate Lactobacillus species. It has been shown that the administration of lactoferrin (LF), a prebiotic with minimum side effects, may be effective in suppressing PTB. This hypothesis has been evaluated in this review using various relevant test examples. The findings suggest that LF may play a role in inflammatory protection in pregnant human cervical tissue. The antibacterial and anti-cytokine effects of LF in human-derived mucus-producing cervical cell lines were also demonstrated. It was also clarified that LF suppresses PTB and improves the prognosis of pups in inflammation-induced PTB animal models. Thus, we have identified that LF, a prebiotic contained in breast milk, can be clinically applied to suppress PTB in humans and to prevent PTBs in high-risk pregnancies.

Lactoferrin: An Effective Weapon in the Battle Against Bacterial Infections

The emergence of multidrug-resistant bacterial strains with respect to commercially available antimicrobial drugs has marked a watershed in treatment therapies to fight pathogens and has stimulated research on alternative remedies. Proteins of the innate immune system of mammals have been highlighted as potentially yielding possible treatment options for infections. Lactoferrin (Lf) is one of these proteins; interestingly, no resistance to it has been found. Lf is a conserved cationic nonheme glycoprotein that is abundant in milk and is also present in low quantities in mucosal secretions. Moreover, Lf is produced and secreted by the secondary granules of neutrophils at infection sites. Lf is a molecule of approximately 80 kDa that displays multiple functions, such as antimicrobial, anti-viral, anti-inflammatory, and anticancer actions. Lf can synergize with antibiotics, increasing its potency against bacteria. Lactoferricins (Lfcins) are peptides resulting from the N-terminal end of Lf by proteolytic cleavage with pepsin. They exhibit several anti-bacterial effects similar to those of the parental glycoprotein. Synthetic analog peptides exhibiting potent antimicrobial properties have been designed. The aim of this review is to update understanding of the structure and effects of Lf and Lfcins as anti-bacterial compounds, focusing on the mechanisms of action in bacteria and the use of Lf in treatment of infections in patients, including those studies where no significant differences were found. Lf could be an excellent option for prevention and treatment of bacterial diseases, mainly in combined therapies with antibiotics or other antimicrobials.

Antimicrobial and Prebiotic Activity of Lactoferrin in the Female Reproductive Tract: A Comprehensive Review

Women’s intimate health depends on several factors, such as age, diet, coexisting metabolic disorders, hormonal equilibrium, sexual activity, drug intake, contraception, surgery, and personal hygiene. These factors may affect the homeostasis of the internal environment of the genital tract: the vulva, vagina and cervix. This equilibrium is dependent on strict and complex mutual interactions between epithelial cells, immunocompetent cells and microorganisms residing in this environment. The microbiota of the genital tract in healthy women is dominated by several species of symbiotic bacteria of the Lactobacillus genus. The bacteria inhibit the growth of pathogenic microorganisms and inflammatory processes by virtue of direct and multidirectional antimicrobial action and, indirectly, by the modulation of immune system activity. For the homeostasis of the genital tract ecosystem, antimicrobial and anti-inflammatory peptides, as well as proteins secreted by mucus cells into the cervicovaginal fluid, have a fundamental significance. Of these, a multifunctional protein known as lactoferrin (LF) is one of the most important since it bridges innate and acquired immunity. Among its numerous properties, particular attention should be paid to prebiotic activity, i.e., exerting a beneficial action on symbiotic microbiota of the gastrointestinal and genital tract. Such activity of LF is associated with the inhibition of bacterial and fungal infections in the genital tract and their consequences, such as endometritis, pelvic inflammation, urinary tract infections, miscarriage, premature delivery, and infection of the fetus and newborns. The aim of this article is to review the results of laboratory as well as clinical trials, confirming the prebiotic action of LF on the microbiota of the lower genital tract.

Vaginal microbiome as a tool for prediction of chorioamnionitis in preterm labor: a pilot study

Intra-amniotic infection (IAI) is a major cause of preterm birth with a poor perinatal prognosis. We aimed to determine whether analyzing vaginal microbiota can evaluate the risk of chorioamnionitis (CAM) in preterm labor cases. Vaginal discharge samples were collected from 83 pregnant women admitted for preterm labor. Based on Blanc’s classification, the participants were divided into CAM (stage ≥ II; n = 46) and non-CAM (stage ≤ I; n = 37) groups. The 16S rDNA amplicons (V1–V2) from vaginal samples were sequenced and analyzed. Using a random forest algorithm, the bacterial species associated with CAM were identified, and a predictive CAM (PCAM) scoring method was developed. The α diversity was significantly higher in the CAM than in the non-CAM group (P < 0.001). The area under the curve was 0.849 (95% confidence interval 0.765–0.934) using the PCAM score. Among patients at < 35 weeks of gestation, the PCAM group (n = 22) had a significantly shorter extended gestational period than the non-PCAM group (n = 25; P = 0.022). Multivariate analysis revealed a significant difference in the frequency of developmental disorders in 3-year-old infants (PCAM, 28%, non-PCAM, 4%; P = 0.022). Analyzing vaginal microbiota can evaluate the risk of IAI. Future studies should establish appropriate interventions for IAI high-risk patients to improve perinatal prognosis.

Lactoferrin for Prevention and Treatment of Anemia and Inflammation in Pregnant Women: A Comprehensive Review

Pregnancy is a physiological state that demands higher level of nutrients, including vitamins and minerals, for the growth and maintenance of the fetus. Iron deficiency is a part of most common diet deficiencies in pregnancy and has high clinical significance leading to the development of syderopenic anemia and its consequences for mother and child, such as higher risk of perinatal death, susceptibility to infection, intra-uteral growth inhibition, prematurity and low birth weight. Hence, iron supplementation is recommended for pregnant women; however dietary intake of iron from most commercially available formulas is often insufficient due to iron-poor bioavailability, or have undesired side-effects in the gastrointestinal tract, resulting in a discouraging and distrustful attitude to such treatment. The results of numerous studies indicate that diet supplementation with lactoferrin (LTF), an iron-binding protein, may be advantageous in prophylaxis and treatment of iron deficiency anemia. LTF, administered orally, normalizes iron homeostasis, not only by facilitating iron absorption, but also by inhibiting inflammatory processes responsible for anemia of chronic diseases, characterized by a functional iron deficit for physiological processes. LTF also protects against infections and inflammatory complications, caused by diagnostic surgical interventions in pregnant women. Beneficial, multidirectional actions of LTF during pregnancy encompass, in addition, inhibition of oxidative stress, normalization of intestine and genital tract microbiota and carbohydrate-lipid metabolism, protection of intestine barrier function, promotion of wound healing, as well as hypotensive, analgesic and antistress actions. Bovine lactoferrin (BLTF) is readily available on the nutritional market and generally recognized as safe (GRAS) for use in human diet.

Lactoferrin nanoparticles coencapsulated with curcumin and tenofovir improve vaginal defense against HIV-1 infection

Aim: We report here the development of tenofovir- and curcumin-loaded lactoferrin nanoparticles (TCNPs) as an HIV-microbicide. Materials & methods: TCNPs were subjected to various physicochemical characterization experiments, followed by in vitro and in vivo experiments to assess their efficacy. Results: TCNPs had a diameter of 74.31 ± 2.56 nm with a gross encapsulation of more than 61% for each drug. Nanoparticles were effective against HIV-1 replication, with an IC₅₀ of 1.75 μM for curcumin and 2.8 μM for tenofovir. TCNPs provided drug release at the application site for up to 8-12 h, with minimal leakage into the systemic circulation. TCNPs showed spermicidal activity at ≥200 μM and induced minimal cytotoxicity and inflammation in the vaginal epithelium as revealed by histopathological and ELISA studies. Conclusion: We demonstrated that TCNPs could serve as a novel anti-HIV microbicidal agent in rats. [Formula: see text].

Warding Off Recurrent Yeast and Bacterial Vaginal Infections: Lactoferrin and Lactobacilli

Vaginal infections are the most prevalent women's health problem. Incompetent diagnosis, inappropriate treatments, and antibiotic resistance are the main causes of the unsatisfactory results of conventional, antimicrobic treatment for these infections. Research has thus been conducted to identify new treatments for these genital diseases. The significant enhancement in our knowledge of vaginal microbiota has permitted the development of new, nonpharmacological strategies for the treatment of vaginal infections that seek to restore the balance of vaginal microflora, as opposed to modifying its components. Among these approaches, bioactive compounds, such as probiotics and nutraceutical proteins (such as lactoferrin), deserve particular attention. The aim of this review is to examine the role of probiotics (mainly Lactobacillus spp.) and lactoferrin as new strategies for counteracting bacterial and fungal vaginal infections.

Vaginal lactoferrin in prevention of preterm birth in women with bacterial vaginosis

Objective: To evaluate use of vaginal lactoferrin in prevention of preterm birth (PTB) in women with first trimester bacterial vaginosis and prior spontaneous PTB.Methods: This is a retrospective cohort study of all consecutive singleton gestations with prior PTB, and first trimester diagnosis of bacterial vaginosis. Women who were found to have bacterial vaginosis were recommended lactoferrin 300 mg vaginal tablets daily for 21 days. The primary outcome was the incidence of PTB at less than 37 weeks of gestations. Outcomes were compared in women who received daily lactoferrin with those who did notResults: During the study period, 847 pregnant women with prior spontaneous PTB were screened for bacterial vaginosis. Of them, 193 were found to have bacterial vaginosis in the first trimester, with an overall incidence of 22.8%. Out of the 193 women, 125 met the inclusion criteria for the study and were analyzed. Sixty of the included women received vaginal lactoferrin, while 65 did not. Women who received supplementation with lactoferrin had a significantly lower rate of PTB < 37 weeks (25.0 versus 44.6%; p = .02), lower mean gestational age at delivery (37.7 ± 3.2 versus 35.9 ± 4.1 weeks; p = .01), and lower rate of admission for threatened PTL (45.0 versus 70.8%; p = .04). No between-group differences were noticed in the other outcomes, including chorioamnionitis, PPROM < 34 weeks, and neonatal outcomes. No cases of late miscarriage were reported in our cohort. No cases of adverse events were reported.Conclusion: Based on this small single-center retrospective study, supplementation with vaginal lactoferrin in women with first trimester bacterial vaginosis may be an option to reduce the risk of preterm delivery.

A pilot study and case reports on endometrial microbiota and pregnancy outcome: An analysis using 16S rRNA gene sequencing among IVF patients, and trial therapeutic intervention for dysbiotic endometrium

PURPOSE

The present study aimed to analyze the pregnancy outcomes of IVF patients presenting Lactobacillus-dominated microbiota (LDM) or non-Lactobacillus-dominated microbiota (NLDM) of their endometrium and to report cases who were treated for NLDM concurrently with antibiotics and prebiotic/probiotic supplements in a Japanese infertile population.

METHODS

Ninety-two IVF patients were recruited from August 2017 to March 2018. Endometrial fluid samples for sequencing were collected using an IUI catheter. The bacterial status of the endometrium and the pregnancy outcomes were analyzed. For cases with NLDM, antibiotics and prebiotics/probiotics were administered according to their individual microbial conditions.

RESULTS

Forty-seven cases (51.1%) presented LDM and 45 cases (48.9%) presented NLDM at initial analysis. Nine Patients with NLDM were treated by antibiotics and prebiotics/probiotics, and successfully became Lactobacillus-dominant. Pregnancy rates by single vitrified-warmed blastocyst transfers were higher in the LDM group (58.9% per patient and 36.3% per FBT) than in the NLDM group (47.2% per patient and 34.7% per FBT) but not significantly different.

CONCLUSION

The results of this study could not necessarily prove the clear benefit of establishing Lactobacillus-dominated endometrium in terms of pregnancy outcome, but there is significance in searching for endometrial microbial status of infertile patients and recovering Lactobacillus-dominated endometrium might benefit implantation.

Psychosocial Stress, Cortisol Levels, and Maintenance of Vaginal Health

Stress stimuli are ubiquitous and women do not enjoy any exemptions. The physiologic "fight-or-flight" response may be deleterious to the female lower genital tract microbiome if the stress stimuli persist for longer than necessary. Persistent exposure to psychosocial stress and stimulation of the hypothalamic-pituitary-adrenal (HPA) and sympathetic-adrenal-medullary (SAM) axes, and associated hormones are risk factors for several infections including genitourinary tract infections. Though this could be due to a dysregulated immune response, a cortisol-induced inhibition of vaginal glycogen deposition may be involved especially in the instance of vaginal infection. The estrogen-related increased vaginal glycogen and epithelial maturation are required for the maintenance of a healthy vaginal ecosystem (eubiosis). The ability of cortisol to disrupt this process as indicated in animal models is important in the pathogenesis of vaginal dysbiosis and the subsequent development of infection and inflammation. This phenomenon may be more crucial in pregnancy where a healthy Lactobacillus-dominated vaginal microbiota is sacrosanct, and there is local production of more corticotropin-releasing hormone (CRH) from the decidua, fetal membranes and placenta. To highlight the relationship between the stress hormone cortisol and the vaginal microbiomial architecture and function, the potential role of cortisol in the maintenance of vaginal health is examined.

Group B Streptococcus Induces Neutrophil Recruitment to Gestational Tissues and Elaboration of Extracellular Traps and Nutritional Immunity

Streptococcus agalactiae, or Group B Streptococcus (GBS), is a gram-positive bacterial pathogen associated with infection during pregnancy and is a major cause of morbidity and mortality in neonates. Infection of the extraplacental membranes surrounding the developing fetus, a condition known as chorioamnionitis, is characterized histopathologically by profound infiltration of polymorphonuclear cells (PMNs, neutrophils) and greatly increases the risk for preterm labor, stillbirth, or neonatal GBS infection. The advent of animal models of chorioamnionitis provides a powerful tool to study host-pathogen relationships in vivo and ex vivo. The purpose of this study was to evaluate the innate immune response elicited by GBS and evaluate how antimicrobial strategies elaborated by these innate immune cells affect bacteria. Our work using a mouse model of GBS ascending vaginal infection during pregnancy reveals that clinically isolated GBS has the capacity to invade reproductive tissues and elicit host immune responses including infiltration of PMNs within the choriodecidua and placenta during infection, mirroring the human condition. Upon interacting with GBS, murine neutrophils elaborate DNA-containing extracellular traps, which immobilize GBS and are studded with antimicrobial molecules including lactoferrin. Exposure of GBS to holo- or apo-forms of lactoferrin reveals that the iron-sequestration activity of lactoferrin represses GBS growth and viability in a dose-dependent manner. Together, these data indicate that the mouse model of ascending infection is a useful tool to recapitulate human models of GBS infection during pregnancy. Furthermore, this work reveals that neutrophil extracellular traps ensnare GBS and repress bacterial growth via deposition of antimicrobial molecules, which drive nutritional immunity via metal sequestration strategies.

Early life diets with prebiotics and bioactive milk fractions attenuate the impact of stress on learned helplessness behaviours and alter gene expression within neural circuits important for stress resistance

Manipulating gut microbes may improve mental health. Prebiotics are indigestible compounds that increase the growth and activity of health-promoting microorganisms, yet few studies have examined how prebiotics affect CNS function. Using an acute inescapable stressor known to produce learned helplessness behaviours such as failure to escape and exaggerated fear, we tested whether early life supplementation of a blend of two prebiotics, galactooligosaccharide (GOS) and polydextrose (PDX), and the glycoprotein lactoferrin (LAC) would attenuate behavioural and biological responses to stress later in life. Juvenile, male F344 rats were fed diets containing either GOS and PDX alone, LAC alone, or GOS, PDX and LAC. All diets altered gut bacteria, while diets containing GOS and PDX increased Lactobacillus spp. After 4 weeks, rats were exposed to inescapable stress, and either immediately killed for blood and tissues, or assessed for learned helplessness 24 h later. Diets did not attenuate stress effects on spleen weight, corticosterone and blood glucose; however, all diets differentially attenuated stress-induced learned helplessness. Notably, in situ hybridization revealed that all diets reduced stress-evoked cfos mRNA in the dorsal raphe nucleus (DRN), a structure important for learned helplessness behaviours. In addition, GOS, PDX and LAC diet attenuated stress-evoked decreases in mRNA for the 5-HT_1A autoreceptor in the DRN and increased basal BDNF mRNA within the prefrontal cortex. These data suggest early life diets containing prebiotics and/or LAC promote behavioural stress resistance and uniquely modulate gene expression in corresponding circuits.

Transcriptomic Insights into the Response of Placenta and Decidua Basalis to the CpG Oligodeoxynucleotide Stimulation in Non-Obese Diabetic Mice and Wild-Type Controls

Intrauterine infection is one of the most frequent causes of miscarriage. CpG oligodeoxynucleotide (CpG ODN) can mimic intrauterine infection. CpG ODN-induced embryo-resorption was observed consistently in the NK-cell deficient non-obese diabetic (NOD) mice but not in the wild-type (WT) mice. To elucidate the molecular mechanisms of differential pregnancy outcomes, differentially expressed genes (DEGs) in the placenta and decidua basalis was revealed by RNA-Seq with CpG ODN or control ODN treatment. Common DEGs in the WT and NOD mice were enriched in antimicrobial/antibacterial humoral responses that may be activated as a primary response to bacterial infection. The susceptibility to CpG ODN-induced embryo-resorption in the NOD mice might mainly be attributed to M1 macrophage polarization and the immunodeficient status, such as the down-regulation in antigen processing and presentation, allograft rejection, and natural killer cell mediated cytotoxicity. In contrast, the WT mice with normal immune systems could activate multiple immune responses and be resistant to CpG ODN-induced embryo-resorption, such as M2 macrophage differentiation and activation regulated by complement component C1q and peroxisome proliferation-activated receptor (PPAR) signaling pathways. Collectively, this study suggests that the immunodeficient status of NOD mice and the macrophage polarization regulated by C1q and PPAR signaling might be the basis for differential pregnancy outcomes between the NOD and WT mice.

Bacterial Vaginosis Biofilms: Challenges to Current Therapies and Emerging Solutions

Bacterial vaginosis (BV) is the most common genital tract infection in women during their reproductive years and it has been associated with serious health complications, such as preterm delivery and acquisition or transmission of several sexually transmitted agents. BV is characterized by a reduction of beneficial lactobacilli and a significant increase in number of anaerobic bacteria, including Gardnerella vaginalis, Atopobium vaginae, Mobiluncus spp., Bacteroides spp. and Prevotella spp.. Being polymicrobial in nature, BV etiology remains unclear. However, it is certain that BV involves the presence of a thick vaginal multi-species biofilm, where G. vaginalis is the predominant species. Similar to what happens in many other biofilm-related infections, standard antibiotics, like metronidazole, are unable to fully eradicate the vaginal biofilm, which can explain the high recurrence rates of BV. Furthermore, antibiotic therapy can also cause a negative impact on the healthy vaginal microflora. These issues sparked the interest in developing alternative therapeutic strategies. This review provides a quick synopsis of the currently approved and available antibiotics for BV treatment while presenting an overview of novel strategies that are being explored for the treatment of this disorder, with special focus on natural compounds that are able to overcome biofilm-associated antibiotic resistance.

Is there a role for probiotics in the prevention of preterm birth?

Preterm birth (PTB) continues to be a global health challenge. An over-production of inflammatory cytokines and chemokines, as well as an altered maternal vaginal microbiome has been implicated in the pathogenesis of inflammation/infection-associated PTB. Lactobacillus represents the dominant species in the vagina of most healthy pregnant women. The depletion of Lactobacillus in women with bacterial vaginosis (BV) has been associated with an increased risk of PTB. It remains unknown at what point an aberrant vaginal microbiome composition specifically induces the cascade leading to PTB. The ability of oral or vaginal lactobacilli probiotics to reduce BV occurrence and/or dampen inflammation is being considered as a means to prevent PTB. Certain anti-inflammatory properties of lactobacilli suggest potential mechanisms. To date, clinical studies have not been powered with sufficiently high rates of PTB, but overall, there is merit in examining this promising area of clinical science.