Diletta Francesca Squarzanti

Oral lichen planus (OLP) is a chronic inflammatory oral disease associated with immune dysregulation and malignant transformation risk. Vitamin D and probiotics may modulate immune and microbial pathways involved in OLP. In this study, we evaluated their effects on clinical outcomes and multi-omics profiles in 25 adult OLP patients (median age: 68 years). Vitamin D-deficient patients received 2000 IU/day vitamin D3, and all participants received a probiotic blend (Limosilactobacillus reuteri LRE11, Lacticaseibacillus rhamnosus LR04, and Lacticaseibacillus casei LC04) for 16 weeks. Clinical assessments and analyses of saliva, serum, oral swabs, and stool samples were performed before and after treatment. Clinical outcomes improved significantly, with reductions in lesion number (p < 0.001), lesion size (p = 0.004), and bleeding lesions (p = 0.014); 76% of patients were classified as in remission. Vitamin D levels increased significantly among deficient patients receiving correction (p < 0.01). Salivary and fecal metabolomics showed significant remodeling of amino acid and carbohydrate pathways, including decreases in branched-chain amino acids in saliva and modulation of nicotinamide- and amino acid-related metabolites in feces. Microbiome α-diversity remained stable, whereas β-diversity shifted significantly across oral and fecal sites, with enrichment of Lacticaseibacillus and other context-dependent commensals. Multi-omics integration identified three latent factors linking salivary cytokines, microbial taxa, metabolites, and systemic lipid profiles, suggesting coordinated mucosal–metabolic–immune remodeling across the oral–gut axis.

Oral lichen planus (OLP) is a chronic inflammatory oral disease associated with immune dysregulation and malignant transformation risk. Vitamin D and probiotics may modu-late immune and microbial pathways involved in OLP. In this study, we evaluated their effects on clinical outcomes and multi-omics profiles in 25 adult OLP patients. Vitamin D-deficient patients received 2,000 IU/day vitamin D3, and all participants received a probiotic blend (Limosilactobacillus reuteri LRE11, Lactica-seibacillus rhamnosus LR04, and Lacticaseibacillus casei LC04) for 16 weeks. Clinical assess-ments and analyses of saliva, serum, oral swabs, and stool samples were performed be-fore and after treatment. Following the intervention, 76% of participants achieved clinical remission. Significant metabolomic changes were observed mainly in saliva and feces. Serum cytokines, me-tabolites, and lipoproteins showed no significant differences. Microbiome profiling demonstrated treatment-related compositional shifts in oral and fecal samples, including increased Lacticaseibacillus abundance. Multi-omics integration identified coordinated in-teractions among microbial, metabolic, immune, and lipid pathways, highlighting inter-connected gut-oral biological responses. Combined vitamin D and probiotic supplementation was associated with clinical im-provement and coordinated oral-intestinal multi-omics changes, supporting a sys-tems-level understanding of OLP remission. These findings suggest that modulating the microbiota-metabolism-immunity axis could represent a promising therapeutic strategy for achieving sustained disease control and clinical remission.

The close connections between the intestine and distal systems, known as axes, are a growing focus of scientific research; however, the gut–vascular axis, particularly as a target of microbial metabolites, remains underexplored. In this study, three supernatants derived from probiotic formulations composed of Lactobacillus and Bifidobacterium strains (MIX-1, MIX-2, and MIX-3) were evaluated in counteracting vascular alterations associated with dysbiosis. Human aortic smooth muscle (HASMCs) and endothelial (HAECs) cells were exposed to pro-oxidative (H₂O₂) and pro-inflammatory (TMAO) stimuli. Concentrations up to 5–10% (v/v) were tolerated in both cell lines, with MIX-1 and MIX-3 showing the greatest protective efficacy. These formulations exerted antioxidant effects by reducing H₂O₂-induced ROS production and cell viability loss, and anti-inflammatory effects by limiting TMAO-induced IL-1β release. MIX-1 also attenuated TMAO-induced IL-6 release. Further analyses indicated a partial involvement of the SIRT1-pathway in its vascular antioxidant effects. Chromatographic profiling revealed comparable qualitative metabolites among the probiotic supernatants, while quantitative differences were observed, with higher lactate levels in MIX-1 and MIX-3 compared to MIX-2. Finally, we have determined that Limosilactobacillus reuteri-PBS072 is mainly responsible for the antioxidant effect of MIX-1 and MIX-3. Overall, these findings highlight the potential of probiotic-derived metabolites in modulating the gut–vascular axis and promoting vascular protection.

Elderly individuals are more vulnerable to disease due to their increased frailty. Emerging evidence highlights the potential of probiotics as geroprotective agents by maintaining gut health and modulating key physiological processes involved in aging, such as inflammation, cognitive functions, and metabolism. Here, we investigated the geroprotective potential of four probiotic strains (Lacticaseibacillus paracasei LPC1114, Limosilactobacillus reuteri PBS072, Bifidobacterium breve BB077, and Bifidobacterium animalis subsp. lactis BL050) using Caenorhabditis elegans as an aging model. Mid-life healthspan parameters were assessed, including lifespan, motility, ROS levels, lipofuscin accumulation, and cognitive capabilities. The probiotics exhibited strain-specific effects. L. reuteri PBS072 and B. lactis BL050 significantly increased locomotion by 20% and decreased ROS levels by 70% and 30% respectively, suggesting enhanced oxidative stress response and neuromuscular maintenance. B. breve BB077, L. paracasei LPC1114, and L. reuteri PBS072 enhanced associative learning performance, whereas B. lactis BL050 improved chemotactic response. Notably, only L. paracasei LPC1114 and L. reuteri PBS072 extended the maximum lifespan by 4 and 5 days, respectively, an effect mediated by the longevity-related genes skn1, sir2.1, and daf16. Our findings highlight the multifaceted, strain-specific geroprotective properties of probiotics and support their potential as microbiome-based interventions to promote healthy aging.

The concept of well-aging focuses on maintaining skin health and appearance through cosmetic and nutritional strategies. Among these, probiotics have gained interest in their potential to enhance skin health, hydration, and barrier. This randomized, placebo-controlled clinical study evaluated the efficacy of a probiotic-based dietary supplement in improving key skin aging parameters. Sixty-six participants received either the active or the placebo supplement for 56 days, followed by a 28-day follow-up to assess the lasting effect. Skin assessments included 3D profilometry, high-frequency ultrasound, moisturization, transepidermal water loss (TEWL), and oxidative stress evaluation. After 28 and 56 days, the probiotic group showed significant improvements compared to placebo, including reduced wrinkle depth (–10.4% at T28; –15.0% at T56) and roughness (–4.3% at T28; –6.1% at T56), increased dermal thickness (+2.5%) and density (+3.31%), enhanced superficial (+11.9% at T28; +16.5% at T56) and deep moisturization (+4.5% at T56), and lower TEWL (–9.7% at T28; –14.5% at T56). Skin antioxidant capacity also increased (+50.3% at T56). Skin improvements were maintained after the follow-up period, supporting the role of probiotics in long-term skin health. These findings reinforce the role of probiotics in well-aging, demonstrating their ability to positively influence skin health through the gut-skin axis even beyond the supplementation period.

Background: Colds are widespread infectious diseases that affect daily life, increasing healthcare costs and limiting productivity. Objectives: The aim of this study was to investigate the effects of a dietary supplement containing specific probiotic strains (L. plantarum PBS067, L. acidophilus PBS066, B. lactis BL050) on cold symptom relief, immune response enhancement, and quality of life. Methods This randomized, double-blind, placebo-controlled trial included 65 healthy volunteers (age range: 18–44 years), divided into two groups: 40 received the probiotic treatment (with vitamins and bulking agents), and 25 received placebo (vitamins and bulking agents only) for 12 weeks. Cold symptoms and systemic inflammation were assessed at three time points (baseline T0, post-treatment T1, and 6 weeks after treatment T2). Results: Probiotics were associated with a shorter average duration of cold symptoms (4.5 vs. 6.7% for Placebo, p < 0.05). At T1, fever and muscle pain occurred in 20% of participants in the Probiotic group vs. 28% and 44% in the Placebo group, respectively (p < 0.05 for muscle pain vs. Placebo). For muscle pain, a trend was maintained also at T2 (17.5% vs. 20%). The pro-inflammatory cytokine IFN-γ levels significantly decreased in the Probiotic group vs. T0 (p < 0.0001 at T1 and p < 0.01 at T2), while they increased in the Placebo group (22.279 ± 3.538 vs. 19.432 ± 3.143 pg/mL, p = NS). Although not statistically significant, at T1 the Probiotic group had higher levels of IL-10 vs. T0 (266.98 ± 78.432 vs. 240.967 ± 70.238, pg/mL p = NS). Conclusions: The probiotic mix effectively alleviated cold symptoms and reduced pro-inflammatory cytokine levels, suggesting anti-inflammatory effects.

Background: Allergic Rhinitis (AR) is an atopic disease affecting the upper airways of predisposed subjects exposed to aeroallergens. This study evaluates the effects of a mix of specific probiotics (L. acidophilus PBS066, L. rhamnosus LRH020, B. breve BB077, and B. longum subsp. longum BLG240) on symptoms and fecal microbiota modulation in subjects with AR. Methods: Probiotic effects were evaluated at the beginning (T0), at four and eight weeks of treatment (T1 and T2, respectively), and after four weeks of follow-up from the end of treatment (T3) (n = 19) compared to the placebo group (n = 22). AR symptoms and quality of life were evaluated by the mini rhinitis quality of life questionnaire (MiniRQLQ) at each time point. Allergic immune response and fecal microbiota compositions were assessed at T0, T2, and T3. The study was registered on Clinical-Trial.gov (NCT05344352). Results: The probiotic group showed significant improvement in the MiniRQLQ score at T1, T2, and T3 vs. T0 (p < 0.01, p < 0.05, p < 0.01, respectively). At T2, the probiotic group showed an increase in Dorea, which can be negatively associated with allergic diseases, and Fusicatenibacter, an intestinal bacterial genus with anti-inflammatory properties (p-value FDR-corrected = 0.0074 and 0.013, respectively). Conversely, at T3 the placebo group showed an increase in Bacteroides and Ruminococcaceae unassigned, (p-value FDR-corrected = 0.033 and 0.023, respectively) which can be associated with allergies, while the probiotic group showed a significative increase in the Prevotella/Bacteroides ratio (p-value FDR-corrected = 0.023). Conclusions: This probiotic formulation improves symptoms and quality of life in subjects with AR, promoting a shift towards anti-inflammatory and anti-allergic bacterial species in the intestinal microbiota.

The microbiota in the oral cavity has a strict connection to its host. Its imbalance may determine oral diseases and can also have an impact on the systemic health. Probiotic strains may help in the restoration of a balanced condition. For this purpose, we screened the antibacterial and antiadhesive activities of many viable probiotic strains (Lactobacillus acidophilus PBS066, Lactobacillus crispatus LCR030, Lactobacillus gasseri LG050, Lactiplantibacillus plantarum PBS067, Limosilactobacillus reuteri PBS072, Lacticaseibacillus rhamnosus LRH020, Bifidobacterium animalis subsp. lactis BL050, Lacticaseibacillus paracasei LPC 1101, L. paracasei LPC 1082, and L. paracasei LPC 1114) against two main oral pathogens, Streptococcus mutans and Aggregatibacter actinomycetemcomitans, involved in dental caries and periodontal disease development and progression. Considering both the agar overlay preventive and treatment models, seven probiotics determined greater inhibition zones against the tested pathogens. This behavior was further analyzed by the plate count method and scanning electron microscope imaging. L. plantarum PBS067, L. rhamnosus LRH020, L. paracasei LPC 1101, L. paracasei LPC 1082, and L. paracasei LPC 1114 prevent the growth and adhesion of oral pathogens in a strain-specific manner (p < 0.0001). These probiotics might be considered as an alternative effective adjuvant to improve oral and systemic well-being for future personalized treatments.

The menopausal transition marks a significant physiological shift in women. Menopause-related symptoms can significantly affect a woman’s quality of life and probiotics have emerged as a promising avenue. This study aims to investigate the benefits of probiotics in improving vaginal well-being and microbiota composition in post-menopausal women. A prospective observational clinical trial was carried out enrolling 50 post-menopausal healthy women, aged between 45 and 65 years old, taking a supplement containing Lactiplantibacillus plantarum PBS067, Bifidobacterium animalis subsp. lactis BL050, and Lacticaseibacillus rhamnosus LRH020 (3B CFU/day) for 28 days. Vaginal swabs were collected to evaluate microbiota fluctuation and the inflammatory pattern was recorded. A Vaginal Health Index was provided to evaluate vaginal well-being throughout the trial. Clinical outcomes revealed a decrease in menopausal symptoms. Significant improvements were observed across various parameters: a 50% enhancement in the VHI score (p < 0.0001), alongside substantial reductions in inflammatory cytokine levels. An 87.8% decrease in IL-6, 57.6% in IL-1β, and 40.8% in TNF-α was observed (p < 0.05). Moreover, the probiotic intervention facilitated the restoration of vaginal microbiota, evidenced by an increase in lactobacilli abundance. In conclusion, the combination of these specific probiotic strains, previously clinically tested in childbearing-age women, showed to be effective also for post-menopausal women.

The microbiota in the oral cavity has a strict connection to its host. Its unbalance may determine oral diseases and can also have an impact on the systemic health. Probiotic strains may help in the restoration of a balanced condition. For this purpose, we screened the antibacterial and antiadhesive activities of many viable probiotic strains (Lactobacillus acidophilus PBS066, Lactobacillus crispatus LCR030, Lactobacillus gasseri LG050, Lactiplantibacillus plantarum PBS067, Limosilactobacillus reuteri PBS072, Lacticaseibacillus rhamnosus LRH020, Bifidobacterium animalis subsp. lactis BL050, Lacticaseibacillus paracasei LPC 1101, L. paracasei LPC 1082, and L. paracasei LPC 1114) against two main oral pathogens, Streptococcus mutans and Aggregatibacter actinomycetemcomitans, involved in dental caries and periodontal disease development and progression. Our results, obtained through agar overlay assay, plate count method, and scanning electron microscope imaging, indicate that the tested probiotics prevent the growth and adhesion of oral pathogens in a strain-specific manner, improving oral health. L. plantarum PBS067, L. rhamnosus LRH020, L. paracasei LPC 1101, L. paracasei LPC 1082, and L. paracasei LPC 1114 performed in a significant way against both pathogens in all the tests used. They can be considered as an effective adjuvant to guarantee oral and systemic well-being.