Introduction
The term "cold" describes a range of respiratory illnesses primarily triggered by viral infections. Colds are the most common infectious diseases in the world, affecting daily life and increasing healthcare costs and lost productivity. Cold symptoms typically emerge 2-3 days after viral exposure. Children and those with a compromised immune system may experience more severe complications. The gut microbiota is directly involved in immune function, and probiotics can restore gut balance and enhance immunity. Specific probiotic strains, including L. plantarum PBS077, L. acidophilus PBS066, and B. lactis BL050, have demonstrated antimicrobial and anti-inflammatory properties.
Aims & Methods
This study aims to evaluate the effects of a dietary supplement containing L. plantarum PBS077, L. acidophilus PBS066, and B. lactis BL050 probiotics on relieving cold symptoms in healthy individuals, focusing on its potential to enhance immune response and improve quality of life (QoL). This randomized, double-blind, placebo-controlled clinical trial was conducted in Italy in winter from 2022 to 2024, involving 65 healthy volunteers aged 18-44. Participants were assigned to two groups: 40 received a probiotic treatment with specific strains (L. plantarum PBS077, L. acidophilus PBS066, B. lactis BL050), B6 and B12 vitamins, folic acid, and bulking agents (Probiotic), while 25 received a placebo, consisting of bulking agents, B6 and B12 vitamins and folic acid, without probiotics (Placebo). Participants took one capsule daily for 12 weeks, with assessments conducted at baseline (T0), after treatment (T1), and 6 weeks post-treatment (T2). Cold symptoms and quality of life (QoL) were assessed using a validated questionnaire (WURSS-21), and systemic inflammation was evaluated through serum cytokine levels (IFN-γ and IL-10) at each time point. The total observation period lasted 18 weeks.
Results
Probiotics were associated with a shorter average duration of cold symptoms (4.5 vs. 6.7 days for the Placebo), with a 32.7% reduction in symptom duration, p<0.05. At T1, fever occurred in 8 out of 40 participants in the Probiotic group (20%) and in 7 out of 25 participants in the Placebo group (28%), p<0.05. Additionally, at T1, muscle pain was reported by 20% of the Probiotic group (8 out of 40) vs. 44% of the Placebo group (11 out of 25). By T2, muscle pain occurred in 17.5% of the Probiotic group (7 out of 40) and 20% of the Placebo group (5 out of 25), p<0.05. At T1, the pro-inflammatory cytokine IFN-γ levels decreased in the Probiotic group compared to T0 (17,946±2,857 vs. 28,962±4,143 pg/ml, p < 0.05) and increased in the Placebo group compared to T0 (22,279±3,538 vs. 19,432±3,143 pg/ml, p < 0.05). Though not statistically significant, at T1 the Probiotic group had higher levels of IL-10 compared to T0 (266,98±78,432 vs. 240,967± 70,238, p>0.05).
Conclusion
The probiotic mix alleviated symptoms in patients with colds and reduced levels of the pro-inflammatory cytokine IFN-γ, demonstrating anti-inflammatory properties.
References
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