Bladder Cancer and Probiotics: What Do We Know So Far?

Bladder cancer is around the 10th most diagnosed cancer, although has a considerable mortality. Recent research and new methodologies have discarded the historical dogma that the bladder (and urine) was sterile under normal conditions. Specifically, only a few studies have reported a detailed analysis of the urinary microbiota in patients with bladder cancer, thus exhibiting a remarkable variability due to the low biomass of the urinary microbiota and the influence of many factors. Nevertheless, this research shows us signals that urinary microbiota is a factor to be considered in the pathophysiology of bladder cancer. More importantly, probiotics could be useful as an adjuvant therapy to reduce the recurrence rate or increase the disease-free period after surgery. In vitro studies and animal assays have shown promising results, but the research in this context has also been scarce, and only a few studies have been conducted in humans. In summary, there is little evidence of the possible beneficial effect of probiotics in controlling the overgrowth of genera that could be involved in the carcinogenesis of bladder cancer. This narrative review aims to compile all the evidence to date on the therapeutic potential of probiotics injected directly into the bladder or orally administered.

Rosacea, microbiome and probiotics: the gut-skin axis.

Rosacea is an inflammatory skin disease involving diverse symptoms with a variable clinical progress which can severely impact the patient's quality of life as well as their mental health. The pathophysiological model of rosacea involves an unbalanced immune system predisposed to excessive inflammation, in addition to vascular and nervous alterations, being certain cutaneous microorganisms' triggers of the symptoms onset. The gut-skin axis explains a bidirectional interaction between skin and gut microbiota in some inflammatory skin diseases such as atopic dermatitis, psoriasis, or rosacea. The introduction and consolidation of the next-generation sequencing in recent years has provided unprecedented information about the microbiome. However, the characterization of the gut and skin microbiota and the impact of the gut-skin axis in patients with rosacea has been little explored, in contrast to other inflammatory skin diseases such as atopic dermatitis or psoriasis. Furthermore, the clinical evolution of patients with rosacea is not always adequate and it is common for them to present a sustained symptomatology with frequent flare-ups. In this context, probiotic supplementation could improve the clinical evolution of these patients as happens in other pathologies. Through this review we aim to establish and compile the basics and directions of current knowledge to understand the mechanisms by which the microbiome influences the pathogenesis of rosacea, and how modulation of the skin and gut microbiota could benefit these patients.

How Our Microbiome Influences the Pathogenesis of Alopecia Areata.

Alopecia areata is a multifactorial autoimmune-based disease with a complex pathogenesis. As in all autoimmune diseases, genetic predisposition is key. The collapse of the immune privilege of the hair follicle leading to scalp loss is a major pathogenic event in alopecia areata. The microbiota considered a bacterial ecosystem located in a specific area of the human body could somehow influence the pathogenesis of alopecia areata, as it occurs in other autoimmune diseases. Moreover, the Next Generation Sequencing of the 16S rRNA bacterial gene and the metagenomic methodology have provided an excellent characterization of the microbiota. The aim of this narrative review is to examine the published literature on the cutaneous and intestinal microbiota in alopecia areata to be able to establish a pathogenic link. In this review, we summarize the influence of the microbiota on the development of alopecia areata. We first introduce the general pathogenic mechanisms that cause alopecia areata to understand the influence that the microbiota may exert and then we summarize the studies that have been carried out on what type of gut and skin microbiota is found in patients with this disease.

Oral intake of Kluyveromyces marxianus B0399 plus Lactobacillus rhamnosus CECT 30579 to mitigate symptoms in COVID-19 patients: A randomized open label clinical trial.

At the beginning of the SARS-CoV-2 pandemic, developing of new treatments to control the spread of infection and decrease morbidity and mortality are necessary. This prospective, open-label, case-control intervention study evaluates the impact of the oral intake of the probiotic yeast Kluyveromyces marxianus B0399 together with Lactobacillus rhamnosus CECT 30579, administered for 30 days, on the evolution of COVID-19 patients. Analysis of the digestive symptoms at the end of the follow up shows a benefit of the probiotic in the number of patients without pyrosis (100% vs 33.3%; p 0.05) and without abdominal pain (100% vs 62.5%; p 0.04). Results also show a better evolution when evaluating the difference in the overall number of patients without non-digestive symptoms at the end of the follow-up (41.7%, vs 13%; p 0.06). The percentage of improvement in the digestive symptoms (65% vs 88%; p value 0.06) and the global symptoms (digestive and non-digestive) (88.6% vs 70.8%; p value 0.03) is higher in the probiotic group. The probiotic was well tolerated with no relevant side effects and high adherence among patients. In conclusion, this coadjutant treatment seems to be promising, although results should be confirmed in new studies with higher number of patients.

Acne, Microbiome, and Probiotics: The Gut-Skin Axis.

The objective of this narrative review was to check the influence of the human microbiota in the pathogenesis of acne and how the treatment with probiotics as adjuvant or alternative therapy affects the evolution of acne vulgaris. Acne is a chronic inflammatory skin disease involving the pilosebaceous units. The pathogenesis of acne is complex and multifactorial involving genetic, metabolic, and hormonal factors in which both skin and gut microbiota are implicated. Numerous studies have shown the bidirectionality between the intestinal microbiota and skin homeostasis, a communication mainly established by modifying the immune system. Increased data on the mechanisms of action regarding the relevance of Cutibacterium acnes, as well as the importance of the gut-skin axis, are becoming known. Diverse and varied in vitro studies have shown the potential beneficial effects of probiotics in this context. Clinical trials with both topical and oral probiotics are scarce, although they have shown positive results, especially with oral probiotics through the modulation of the intestinal microbiota, generating an anti-inflammatory response and restoring intestinal integrity, or through metabolic pathways involving insulin-like growth factor I (IGF-1). Given the aggressiveness of some standard acne treatments, probiotics should continue to be investigated as an alternative or adjuvant therapy.

Probiotics in the Therapeutic Arsenal of Dermatologists.

During the last years, numerous studies have described the presence of significant gut and skin dysbiosis in some dermatological diseases such as atopic dermatitis, psoriasis and acne, among others. How the skin and the gut microbiome play a role in those skin conditions is something to explore, which will shed light on understanding the origin and implication of the microbiota in their pathophysiology. Several studies provide evidence for the influence of probiotic treatments that target the modulation of the skin and intestinal microbiota in those disorders and a positive influence of orally administered probiotics on the course of these dermatosis. The pathologies in which the therapeutic role of the probiotic has been explored are mainly atopic dermatitis, psoriasis and acne. This article aims to review these three dermatological diseases, their relationship with the human microbiota and specially the effect of probiotics usage. In addition, the pathophysiology in each of them and the hypotheses about possible mechanisms of the action of probiotics will be described.

Descriptive Study of Gut Microbiota in Infected and Colonized Subjects by Clostridiodes difficile.

Clostridiodes difficile can lead to a range of situations from the absence of symptoms (colonization) to severe diarrhea (infection). Disruption of gut microbiota provides an ideal environment for infection to occur. Comparison of gut microbiota of infected and colonized subjects could provide relevant information on susceptible groups or protectors to the development of infection, since the presence of certain genera could be related to the inhibition of transition from a state of colonization to infection. Through high-throughput sequencing of 16S rDNA gene, we performed alpha and beta diversity and composition studies on 15 infected patients (Group CDI), 15 colonized subjects (Group P), and 15 healthy controls (Group CTLR). A loss of alpha diversity and richness and a different structure have been evidenced in the CDI and P groups with respect to the CTRL group, but without significant differences between the first two. In CDI and P groups, there was a strong decrease in phylum Firmicutes and an expansion of potential pathogens. Likewise, there was a loss of inhibitory genus of C. difficile germination in infected patients that were partially conserved in colonized subjects. Therefore, infected and colonized subjects presented a gut microbiota that was completely different from that of healthy controls, although similar to each other. It is in composition where we found that colonized subjects, especially in minority genera, presented differences with respect to those infected.