Gerobiotics: probiotics targeting fundamental aging processes

Climbing the longevity pyramid: overview of evidence-driven healthcare prevention strategies for human longevity

Longevity medicine is an emerging and iterative healthcare discipline focusing on early detection, preventive measures, and personalized approaches that aim to extend healthy lifespan and promote healthy aging. This comprehensive review introduces the innovative concept of the "Longevity Pyramid." This conceptual framework delineates progressive intervention levels, providing a structured approach to understanding the diverse strategies available in longevity medicine. At the base of the Longevity Pyramid lies the level of prevention, emphasizing early detection strategies and advanced diagnostics or timely identification of potential health issues. Moving upwards, the next step involves lifestyle modifications, health-promoting behaviors, and proactive measures to delay the onset of age-related conditions. The Longevity Pyramid further explores the vast range of personalized interventions, highlighting the importance of tailoring medical approaches based on genetic predispositions, lifestyle factors, and unique health profiles, thereby optimizing interventions for maximal efficacy. These interventions aim to extend lifespan and reduce the impact and severity of age-related conditions, ensuring that additional years are characterized by vitality and wellbeing. By outlining these progressive levels of intervention, this review offers valuable insights into the evolving field of longevity medicine. This structured framework guides researchers and practitioners toward a nuanced strategic approach to advancing the science and practice of healthy aging.

Consumption of a Probiotic Blend with Vitamin D Improves Immunity, Redox, and Inflammatory State, Decreasing the Rate of Aging-A Pilot Study

There is evidence of the effect of probiotic intake on the immune system. However, the effect probiotics may have on the rate of aging is unknown. The aim of this study is to determine the effect of a probiotic blend on immunity, redox state, inflammation, and the rate of aging or biological age. A group of 10 men and 14 women took, daily for 2 months, a sachet with three probiotics (Bifidobacterium animalis subsp. lactis BSO1, Lactobacillus reuteri LRE02, Lactobacillus plantarum LP14) and vitamin D. Before starting the treatment and after 2 months, peripheral blood was collected. Immune functions were assessed in isolated immune cells, and cytokine concentrations were also measured both in mononuclear cell cultures and plasma. Redox state parameters were also analyzed in whole blood cells. Finally, the Immunity Clock was applied to determine the biological age. Results show that the intake of this probiotic blend in general, in both men and women, improves immunity and decreases the oxidative and inflammatory state. In addition, it rejuvenates the biological age by 10 years on average. It can be concluded that this probiotic blend could be proposed as a good strategy to slow down the aging process, and to achieve healthy aging.

Potential probiotic Lactiplantibacillus plantarum DS1800 extends lifespan and enhances stress resistance in Caenorhabditis elegans model

Probiotics are live microorganisms that provide health benefits when administered in appropriate amounts by improving or restoring the balance of intestinal microbiota. Various functional probiotic products have been developed due to the growing interest in the health-promoting and anti-aging effects of enhancing the gut microbiome. Lactiplantibacillus plantarum species are known for their potential to extend lifespan. However, this activity is strain or isolation source specific, necessitating the identification of individual strain functionalities. This study used the C. elegans model to screen probiotics for life-extension effects and analyze their functions. The 43 lactic-acid bacteria strains isolated from fermented foods, breast milk, and human feces were subjected to longevity assays, and L. plantarum DS1800 was selected to demonstrate the most effective lifespan extension. The average lifespan of Caenorhabditis elegans fed DS1800 increased by 17.36% compared with those fed Escherichia coli OP50. Further analysis of the expression of key genes related to longevity revealed the high expression of the skinhead-1 (skn-1), antibacterial, and heat stress resistance genes via the p38 MAPK pathway. These expression patterns suggest that DS1800 extends the lifespan of C. elegans by enhancing its stress resistance and protecting it against pathogens. Additionally, DS1800 exhibited excellent intestinal adhesion, with 7.56% adhesion to HT-29 cells. Therefore, L. plantarum DS1800 is effective in extending the lifespan of C. elegans and can be used as a functional probiotic.

Anti-aging effects of Lacticaseibacillus paracasei PS117 on cognitive and intestinal health in naturally-aged mice: A focus on senescence-related proteins and microbiota composition

The rising global aging population underscores the urgency of maintaining the health and well-being of the elderly while reducing the healthcare burden. Anti-aging probiotics have emerged as a promising strategy. This study identified a novel anti-senescence probiotic, Lacticaseibacillus paracasei PS117 (PS117). The effects of PS117 and heat-treated PS117 (HT-PS117) supplementation on cognitive function of naturally-aged male mice were investigated. It was found that PS117 supplementation improved the cognitive performance of aged mice in the Y-maze test. Furthermore, the level of senescence-related protein p16INK4a (p16) were reduced, while anti-senescence protein sirtuin 1 (Sirt1) were increased in the hippocampus. In addition, there was an overall improvement in the intestinal function. Distinct changes in the gut microbiota were also identified, suggesting a potential contribution to the beneficial effects of PS117 supplementation. In conclusion, these results suggest that PS117 supplements could improve cognitive and intestinal functions in naturally-aged mice, while HT-117 improves only intestinal function, possibly by improving the gut microbiota composition.

Postbiotics as Molecules Targeting Cellular Events of Aging Brain-The Role in Pathogenesis, Prophylaxis and Treatment of Neurodegenerative Diseases

Aging is the most prominent risk factor for neurodegeneration occurrence. The most common neurodegenerative diseases (NDs), Alzheimer's (AD) and Parkinson's (PD) diseases, are characterized by the incidence of proteinopathy, abnormal activation of glial cells, oxidative stress, neuroinflammation, impaired autophagy and cellular senescence excessive for the patient's age. Moreover, mitochondrial disfunction, epigenetic alterations and neurogenesis inhibition, together with increased blood-brain barrier permeability and gut dysbiosis, have been linked to ND pathogenesis. Since NDs still lack curative treatment, recent research has sought therapeutic options in restoring gut microbiota and supplementing probiotic bacteria-derived metabolites with beneficial action to the host-so called postbiotics. The current review focuses on literature explaining cellular mechanisms involved in ND pathogenesis and research addressing the impact that postbiotics as a whole mixture and particular metabolites, such as short-chain fatty acids (SCFAs), lactate, polyamines, polyphenols, tryptophan metabolites, exopolysaccharides and bacterial extracellular vesicles, have on the ageing-associated processes underlying ND occurrence. The review also discusses the issue of implementing postbiotics into ND prophylaxis and therapy, depicting them as compounds addressing senescence-triggered dysfunctions that are worth translating from bench to pharmaceutical market in response to "silver consumers" demands.

The Probiotic Strain Lactobacillus acidophilus CL1285 Reduces Fat Deposition and Oxidative Stress and Increases Lifespan in Caenorhabditis elegans

Caenorhabditis elegans was recently shown to be a powerful model for studying and identifying probiotics with specific functions. Lactobacillus acidophilus CL1285, Lacticaseibacillus casei LBC80R, and Lacticaseibacillus rhamnosus CLR2, which are three bacteria that were marketed by Bio-K+, were evaluated using the nematode C. elegans to study fat accumulation, lifespan, and resistance to oxidative stress. Although the general effects of probiotics in terms of protection against oxidative stress were highlighted, the CL1285 strain had an interesting and specific feature, namely its ability to prevent fat accumulation in nematodes; this effect was verified by both the Oil Red and Nile Red methods. This observed phenotype requires daf-16 and is affected by glucose levels. In addition, in a daf-16- and glucose-dependent manner, CL1285 extended the lifespan of C. elegans; this effect was unique to CL1285 and not found in the other L. acidophilus subtypes in this study. Our findings indicate that L. acidophilus CL1285 impacts fat/glucose metabolism in C. elegans and provides a basis to further study this probiotic, which could have potential health benefits in humans and/or in mammals.

Probiotics, prebiotics, synbiotics and other microbiome-based innovative therapeutics to mitigate obesity and enhance longevity via the gut-brain axis

The global prevalence of obesity currently exceeds 1 billion people and is accompanied by an increase in the aging population. Obesity and aging share many hallmarks and are leading risk factors for cardiometabolic disease and premature death. Current anti-obesity and pro-longevity pharmacotherapies are limited by side effects, warranting the development of novel therapies. The gut microbiota plays a major role in human health and disease, with a dysbiotic composition evident in obese and aged individuals. The bidirectional communication system between the gut and the central nervous system, known as the gut-brain axis, may link obesity to unhealthy aging. Modulating the gut with microbiome-targeted therapies, such as biotics, is a novel strategy to treat and/or manage obesity and promote longevity. Biotics represent material derived from living or once-living organisms, many of which have therapeutic effects. Pre-, pro-, syn- and post-biotics may beneficially modulate gut microbial composition and function to improve obesity and the aging process. However, the investigation of biotics as next-generation therapeutics has only just begun. Further research is needed to identify therapeutic biotics and understand their mechanisms of action. Investigating the function of the gut-brain axis in obesity and aging may lead to novel therapeutic strategies for obese, aged and comorbid (e.g., sarcopenic obese) patient populations. This review discusses the interrelationship between obesity and aging, with a particular emphasis on the gut microbiome, and presents biotics as novel therapeutic agents for obesity, aging and related disease states.

A proof of concept: Clinical anti-aging efficacy and safety of Lactiplantibacillus plantarum LB244R® applied topically in a double-blinded placebo-controlled study

BACKGROUND

With the increasing age of the westernized population, there is also increasing economic and aesthetic interest in reducing the signs of skin aging. Additionally, the physical aspect of aging can be displeasing and have detrimental effects psychologically in individuals. Probiotics have shown potential as anti-aging agents, albeit proper studies are needed to confirm their potential.

AIMS

Proving that Lactiplantibacillus plantarum LB244R® could alleviate aging signs relative to its placebo vehicle.

PATIENTS/METHODS

In total, 46 subjects were randomly assigned either the ointment with live bacteria, L. plantarum LB244R® or its vehicle ointment, and had to use the assigned ointment twice daily for 56 days. On Day 0, Day 28, and Day 56 subepidermal low echogenic band (SLEB) thickness, dermal density, skin firmness and elasticity, skin hydration, transepidermal water loss (TEWL), skin pH, collagen fiber visualization using confocal microscopy, Crow's feet, spot score, skin smoothness, and complexion radiance were assessed by dermatologists.

RESULTS

All parameters except TEWL improved relative to their baseline (D0) for the active group. L. plantarum LB244R® improved SLEB thickness, dermal density, skin elasticity, skin hydration, and Crow's feet wrinkle score relative to the placebo vehicle ointment.

CONCLUSION

The study demonstrates an anti-aging effect of L. plantarum LB244R® for topical skin use in the first double-blinded, vehicle-ointment placebo-controlled clinical study.

The role of Caenorhabditis elegans in the discovery of natural products for healthy aging

Covering: 2012 to 2023The human population is aging. Thus, the greatest risk factor for numerous diseases, such as diabetes, cancer and neurodegenerative disorders, is increasing worldwide. Age-related diseases do not typically occur in isolation, but as a result of multi-factorial causes, which in turn require holistic approaches to identify and decipher the mode of action of potential remedies. With the advent of C. elegans as the primary model organism for aging, researchers now have a powerful in vivo tool for identifying and studying agents that effect lifespan and health span. Natural products have been focal research subjects in this respect. This review article covers key developments of the last decade (2012-2023) that have led to the discovery of natural products with healthy aging properties in C. elegans. We (i) discuss the state of knowledge on the effects of natural products on worm aging including methods, assays and involved pathways; (ii) analyze the literature on natural compounds in terms of their molecular properties and the translatability of effects on mammals; (iii) examine the literature on multi-component mixtures with special attention to the studied organisms, extraction methods and efforts regarding the characterization of their chemical composition and their bioactive components. (iv) We further propose to combine small in vivo model organisms such as C. elegans and sophisticated analytical approaches ("wormomics") to guide the way to dissect complex natural products with anti-aging properties.

Beyond probiotics: a narrative review on an era of revolution

Whether knowingly or unknowingly, humans have been consuming probiotic microorganisms through traditionally fermented foods for generations. Bacteria, like lactic acid bacteria, are generally thought to be harmless and produce many metabolites that are beneficial for human health. Probiotics offer a wide range of health benefits; however, their therapeutic usage is limited because they are living organisms. As a result, the focus on the health advantages of microbes has recently shifted from viable live probiotics to non-viable microbes made from probiotics. These newly emerging non-viable microbes include paraprobiotics, postbiotics, psychobiotics, nutribiotics, and gerobiotics. Their metabolites can boost physiological health and reveal the therapeutic effects of probiotics. This new terminology in microbes, their traits, and their applications are summarized in the present review.

A micronutrient mixture with collagen peptides, probiotics, cannabidiol, and diet may reduce aging, and development and progression of age-related alzheimer's disease, and improve its treatment

Human aging involves gradual decline in organ functions leading to organ specific age-related chronic diseases such as Alzheimer's disease (AD). Although advances in the development of new drugs, novel surgical procedures, improved diet and lifestyle, have resulted in doubling of lifespan of humans, the quality of life in many cases remains poor because of increased incidence of age-related chronic diseases. Using experimental models of accelerated aging, several cellular defects associated with aging and AD have been identified. Some cellular defects due to increased oxidative stress, chronic inflammation, autophagy defects, mitochondrial dysfunction, and imbalances in the composition probiotics in favor of harmful bacteria over beneficial bacteria are common to both aging and AD, while others such as telomere attrition, loss of collagen, elastin, and hyaluronic acid, failure of DNA repair system, and impaired immune function are unique to aging; and some such as increased production of beta-amyloids, hyperphosphorylation of tau protein, and abnormal behaviors are unique to AD. It is suggested that supplementation with a micronutrient mixture, probiotics, collagen peptides, CBD, and modifications in the diet and lifestyle may reduce the aging processes, and the development, progression of AD, and improve the treatments of this disease.

Nutritional components as mitigators of cellular senescence in organismal aging: a comprehensive review

The process of cellular senescence is rapidly emerging as a modulator of organismal aging and disease. Targeting the development and removal of senescent cells is considered a viable approach to achieving improved organismal healthspan and lifespan. Nutrition and health are intimately linked and an appropriate dietary regimen can greatly impact organismal response to stress and diseases including during aging. With a renewed focus on cellular senescence, emerging studies demonstrate that both primary and secondary nutritional elements such as carbohydrates, proteins, fatty acids, vitamins, minerals, polyphenols, and probiotics can influence multiple aspects of cellular senescence. The present review describes the recent molecular aspects of cellular senescence-mediated understanding of aging and then studies available evidence of the cellular senescence modulatory attributes of major and minor dietary elements. Underlying pathways and future research directions are deliberated to promote a nutrition-centric approach for targeting cellular senescence and thus improving human health and longevity.

Lactobacillus brevis MTCC 1750 enhances oxidative stress resistance and lifespan extension with improved physiological and functional capacity in Caenorhabditis elegans via the DAF-16 pathway

Redox imbalance plays a crucial role in the development of age-related diseases, and resistance to oxidative stress is crucial for optimum longevity and healthy aging. Using the wild-type, mutant and transgenic strains, this study explored the antioxidative potential and lifespan extension benefits of different Lactobacillus strains in Caenorhabditis elegans (C. elegans). We observed that Lactobacillus brevis MTCC 1750 could enhance the resistance of C. elegans against juglone induced oxidative stress by reducing its intracellular reactive oxygen species (ROS) accumulation. Also, live L. brevis MTCC 1750 could prolong the worm's lifespan. These effects are dependent on transcription factor DAF-16 evident with significant upregulation of its target gene sod-3. This also explained the significant improvements in different age-associated changes in physiological and mechanical parameters of the worm by L. brevis MTCC 1750. Further investigations revealed that DAF-16 activation and, its enhanced translocation in the nucleus is independent of DAF-2 or JNK pathway. These findings highlighted L. brevis MTCC 1750 as a potent anti-oxidant source for complementing current antioxidant therapeutic strategies. Nonetheless, the findings showed how different signaling events are regulated based on an organism's diet component, and their consequences on the aging process in multiple species.

Evaluating the Role of Probiotics in the Prevention and Management of Age-Related Diseases

The human lifespan has been significantly increased due to scientific advancements in the management of disease; however, the health span of the aging population does not follow the same trend. Aging is the major risk factor for multimorbidity that is derived from the progressive loss of homeostasis, immunological and stem cell exhaustion, as well as exacerbated inflammation responses. Age-related diseases presenting with high frequencies include neurodegenerative, musculoskeletal, cardiovascular, metabolic diseases and cancer. These diseases can be co-morbid and are usually managed using a disease-specific approach that can eventually lead to polypharmacy, low medication adherence rates and undesired drug-drug interactions. Novel studies suggest targeting the shared biological basis of age-related diseases to retard the onset and manage their manifestations. Harvesting the anti-inflammatory and immunomodulatory capacity of probiotics to tackle the root cause of these diseases, could pose a viable alternative. In this article, a comprehensive review of the effects of probiotic supplementation on the molecular pathogenesis of age-related diseases, and the potential of probiotic treatments as preventative or alleviatory means is attempted. Furthermore, issues on the safety and efficiency of probiotic supplementation, as well as the pitfalls of current clinical studies are discussed, while new perspectives for systematic characterization of probiotic benefits on aged hosts are outlined.

Optimization of parameters for obtaining callus, suspension, and root cultures of meadowsweet (filipendula ulmaria) to isolate the largest number of biologically active substances with geroprotective properties

The study of biologically active substances-secondary metabolites of plants that exhibit geroprotective properties is an actual and popular direction in medicine to prevent early aging. This work aims to select the cultivation parameters for obtaining in vitro cell cultures of meadowsweet containing the largest amount of biologically active substances (BAS) for their further extraction as candidate substances for geroprotectors. To specify the effectiveness of the selected cell culture cultivation parameters, biomass growth for callus and root cultures, growth index, specific growth rate, and viability for suspension cultures was carried out. The study results made it possible to select the nutrient media for the cultivation of cell cultures of meadowsweet. It has been found that the greater the antioxidant activity of the extracts, the greater the antimicrobial properties it exhibits. In this study, cell cultures in vitro and alcohol extracts from the plant Filipendula ulmaria were considered as raw materials rich in candidate substances for geroprotectors. According to the data obtained, the plant is rich in hydroxybenzoic and salicylic acids, spireoside, avicularin, and hyperoside.

Effects of anti-aging interventions on intestinal microbiota

Identifying ways to deal with the challenges presented by aging is an urgent task, as we are facing an aging society. External factors such as diet, exercise and drug therapy have proven to be major elements in controlling healthy aging and prolonging life expectancy. More recently, the intestinal microbiota has also become a key factor in the anti-aging process. As the intestinal microbiota changes with aging, an imbalance in intestinal microorganisms can lead to many age-related degenerative diseases and unhealthy aging. This paper reviews recent research progress on the relationship between intestinal microorganisms and anti-aging effects, focusing on the changes and beneficial effects of intestinal microorganisms under dietary intervention, exercise and drug intervention. In addition, bacteriotherapy has been used to prevent frailty and unhealthy aging. Most of these anti-aging approaches improve the aging process and age-related diseases by regulating the homeostasis of intestinal flora and promoting a healthy intestinal environment. Intervention practices based on intestinal microorganisms show great potential in the field of anti-aging medicine.

Using Microbiome-Based Approaches to Deprogram Chronic Disorders and Extend the Healthspan following Adverse Childhood Experiences

Adverse childhood experiences (ACEs), which can include child trafficking, are known to program children for disrupted biological cycles, premature aging, microbiome dysbiosis, immune-inflammatory misregulation, and chronic disease multimorbidity. To date, the microbiome has not been a major focus of deprogramming efforts despite its emerging role in every aspect of ACE-related dysbiosis and dysfunction. This article examines: (1) the utility of incorporating microorganism-based, anti-aging approaches to combat ACE-programmed chronic diseases (also known as noncommunicable diseases and conditions, NCDs) and (2) microbiome regulation of core systems biology cycles that affect NCD comorbid risk. In this review, microbiota influence over three key cyclic rhythms (circadian cycles, the sleep cycle, and the lifespan/longevity cycle) as well as tissue inflammation and oxidative stress are discussed as an opportunity to deprogram ACE-driven chronic disorders. Microbiota, particularly those in the gut, have been shown to affect host–microbe interactions regulating the circadian clock, sleep quality, as well as immune function/senescence, and regulation of tissue inflammation. The microimmunosome is one of several systems biology targets of gut microbiota regulation. Furthermore, correcting misregulated inflammation and increased oxidative stress is key to protecting telomere length and lifespan/longevity and extending what has become known as the healthspan. This review article concludes that to reverse the tragedy of ACE-programmed NCDs and premature aging, managing the human holobiont microbiome should become a routine part of healthcare and preventative medicine across the life course.

Daily ingestion of Akkermansia mucciniphila for one month promotes healthy aging and increases lifespan in old female mice

The ingestion of certain probiotics has been suggested as a promising nutritional strategy to improve aging. The objective of this work was to evaluate the effects of the daily intake, for a month, of a new probiotic Akkermansia muciniphila (AKK) (2 × 10⁸ cfu/100µL PBS) on behavior, as well as function and redox state of immune cells of old female ICR-CD1 mice (OA group). For this, several behavioral tests were performed, and function and oxidative-inflammatory stress parameters of peritoneal leukocytes were analyzed in OA group, in a group of the same age that did not take AKK (old control, OC group) and in another adult control (AC) group. The results showed, in OA group, a significant improvement of several behavioral responses (coordination, balance, neuromuscular vigor, exploratory ability and anxiety like-behaviors), as well as in immune functions (chemotaxis, phagocytosis, NK activity and lymphoproliferation) and in oxidative stress parameters (glutathione peroxidase and reductase activities, oxidized glutathione and lipid oxidation concentrations) of the peritoneal leukocytes in comparison to those observed in OC group. In addition, peritoneal immune cells from the OA group released lower basal concentrations of pro-inflammatory cytokines (IL-2, IL-6 and TNF-α) compared to those from the OC group. The values of parameters in OA were similar to those in AC group. These improvements in the old mice receiving the probiotic were reflected in an increase in their lifespan. In conclusion, our data indicate that AKK supplementation for a short period could be a good nutritional strategy to promote healthy longevity.

The diversity and composition of the human gut lactic acid bacteria and bifidobacterial microbiota vary depending on age

Aging is associated with gut microbiota alterations, characterized by changes in intestinal microbial diversity and composition. However, no study has yet focused on investigating age-related changes in the low-abundant but potentially beneficial subpopulations of gut lactic acid bacteria (LAB) and Bifidobacterium. Our study found that the subjects' age correlated negatively with the alpha diversity of the gut bifidobacterial microbiota, and such correlation was not observed in the gut LAB subpopulation. Principal coordinate analysis (PCoA) and analysis of distribution of operational taxonomic units (OTUs) revealed that the structure and composition of the gut bifidobacterial subpopulation of the longevous elderly group were rather different from that of the other three age groups. The same analyses were applied to identify age-dependent characteristics of the gut LAB subpopulation, and the results revealed that the gut LAB subpopulation of young adults was significantly different from that of all three elderly groups. Our study identified several potentially beneficial bacteria (e.g., Bifidobacterium breve and Bifidobacterium longum) that were enriched in the longevous elderly group (P < 0.05), and the relative abundance of Bifidobacterium adolescentis decreased significantly with the increase in age (P < 0.05). Although both bifidobacteria and LAB are generally considered as health-promoting taxa, their age-dependent distribution varied from each other, suggesting their different life stage changes and potentially different functional roles. This study provided novel species-level gut bifidobacterial and LAB microbiota profiles of a large cohort of subjects and identified several age-or longevity-associated features and biomarkers. KEY POINTS: • The alpha diversity of the gut bifidobacterial microbiota decreased with age, while LAB did not change. • The structure and composition of the gut bifidobacterial subpopulation of the longevous elderly group were rather different from that of the other three age groups. • Several potentially beneficial bacteria (e.g., Bifidobacterium breve and Bifidobacterium longum) that were enriched in the longevous elderly group.

Novel Insights into the Role of Probiotics in Respiratory Infections, Allergies, Cancer, and Neurological Abnormalities

In recent years, probiotics have attracted public attention and transformed the social perception of microorganisms, convening a beneficial role/state on human health. With aging, the immune system, body physiology, and intestinal microbiota tend to change unfavorably, resulting in many chronic conditions. The immune-mediated disorders can be linked to intestinal dysbiosis, consequently leading to immune dysfunctions and a cluster of conditions such as asthma, autoimmune diseases, eczema, and various allergies. Probiotic bacteria such as Lactobacillus and Bifidobacterium species are considered probiotic species that have a great immunomodulatory and anti-allergic effect. Moreover, recent scientific and clinical data illustrate that probiotics can regulate the immune system, exert anti-viral and anti-tumoral activity, and shields the host against oxidative stress. Additionally, microbiota programming by probiotic bacteria can reduce and prevent the symptoms of respiratory infections and ameliorate the neurological status in humans. This review describes the most recent clinical findings, including safe probiotic therapies aiming to medicate respiratory infections, allergies, cancer, and neurological disorders due to their physiological interconnection. Subsequently, we will describe the major biological mechanism by which probiotic bacteriotherapy expresses its anti-viral, anti-allergic, anticancer, and neuro-stimulatory effects.

The Role of the Microbiota-Gut-Brain Axis in the Health and Illness Condition: A Focus on Alzheimer's Disease

Trillions of commensal microbes live in our body, the majority in the gut. This gut microbiota is in constant interaction with the homeostatic systems, the nervous, immune and endocrine systems, being fundamental for their appropriate development and function as well as for the neuroimmunoendocrine communication. The health state of an individual is understood in the frame of this communication, in which the microbiota-gut-brain axis is a relevant example. This bidirectional axis is constituted in early age and is affected by many environmental and lifestyle factors such as diet and stress, among others, being involved in the adequate maintenance of homeostasis and consequently in the health of each subject and in his/her rate of aging. For this, an alteration of gut microbiota, as occurs in a dysbiosis, and the associated gut barrier deterioration and the inflammatory state, affecting the function of immune, endocrine and nervous systems, in gut and in all the locations, is in the base of a great number of pathologies as those that involve alterations in the brain functions. There is an age-related deterioration of microbiota and the homeostatic systems due to oxi-inflamm-aging, and thus the risk of aging associated pathologies such as the neurodegenerative illness. Currently, this microbiota-gut-brain axis has been considered to have a relevant role in the pathogenesis of Alzheimer's disease and represents an important target in the prevention and slowdown of the development of this pathology. In this context, the use of probiotics seems to be a promising help.

Nicotinamide Phosphoribosyltransferase as a Key Molecule of the Aging/Senescence Process

Aging is a phenomenon underlined by complex molecular and biochemical changes that occur over time. One of the metabolites that is gaining strong research interest is nicotinamide adenine dinucleotide, NAD+, whose cellular level has been shown to decrease with age in various tissues of model animals and humans. Administration of NAD+ precursors, nicotinamide mononucleotide (NMN) and nicotinamide riboside (NR), to supplement NAD+ production through the NAD+ salvage pathway has been demonstrated to slow down aging processes in mice. Therefore, NAD+ is a critical metabolite now understood to mitigate age-related tissue function decline and prevent age-related diseases in aging animals. In human clinical trials, administration of NAD+ precursors to the elderly is being used to address systemic age-associated physiological decline. Among NAD+ biosynthesis pathways in mammals, the NAD+ salvage pathway is the dominant pathway in most of tissues, and NAMPT is the rate limiting enzyme of this pathway. However, only a few activators of NAMPT, which are supposed to increase NAD+, have been developed so far. In this review, we will focus on the importance of NAD+ and the possible application of an activator of NAMPT to promote successive aging.