Dietary supplementation with probiotics improves hematopoiesis in malnourished mice

Protection from environmental enteric dysfunction and growth improvement in malnourished newborns by amplification of secretory IgA

Environmental enteric dysfunction (EED) is a condition associated with malnutrition that can progress to malabsorption and villous atrophy. Severe EED results in linear growth stunting, slowed neurocognitive development, and unresponsiveness to oral vaccines. Prenatal exposure to malnutrition and breast feeding by malnourished mothers replicates EED. Pups are characterized by deprivation of secretory IgA (SIgA) and altered development of the gut immune system and microbiota. Extracellular ATP (eATP) released by microbiota limits T follicular helper (Tfh) cell activity and SIgA generation in Peyer's patches (PPs). Administration of a live biotherapeutic releasing the ATP-degrading enzyme apyrase to malnourished pups restores SIgA levels and ameliorates stunted growth. SIgA is instrumental in improving the growth and intestinal immune competence of mice while they are continuously fed a malnourished diet. The analysis of microbiota composition suggests that amplification of endogenous SIgA may exert a dominant function in correcting malnourishment dysbiosis and its consequences on host organisms, irrespective of the actual microbial ecology.

An Updated View of the Effect of Probiotic Supplement on Sports Performance: A Detailed Review

PURPOSE OF REVIEW

Modulation of the host microbiota through probiotics has been shown to have beneficial effects on health in the growing body of research. Exercise increases the amount and diversity of beneficial microorganisms in the host microbiome. Although low- and moderate-intensity exercise has been shown to reduce physiological stress and improve immune function, high-intensity prolonged exercise can suppress immune function and reduce microbial diversity due to intestinal hypoperfusion. The effect of probiotic supplementation on sports performance is still being studied; however, questions remain regarding the mechanisms of action, strain used, and dose. In this review, the aim was to investigate the effects of probiotic supplements on exercise performance through modulation of gut microbiota and alleviation of GI symptoms, promotion of the immune system, bioavailability of nutrients, and aerobic metabolism.

RECENT FINDINGS

Probiotic supplementation may improve sports performance by reducing the adverse effects of prolonged high-intensity exercise. Although probiotics have been reported to have positive effects on sports performance, information about the microbiome and nutrition of athletes has not been considered in most current studies. This may have limited the evaluation of the effects of probiotic supplementation on sports performance.

Can Lacticaseibacillus rhamnosus CRL1505 postbiotic improve emergency myelopoiesis in immunocompromised mice?

We evaluated whether viable and non-viable Lacticaseibacillus rhamnosus CRL1505 (Lr05V or Lr05NV, respectively) was able to improve emergency myelopoiesis induced by Streptococcus pneumoniae (Sp) infection. Adult Swiss-mice were orally treated with Lr05V or Lr05NV during five consecutive days. The Lr05V and Lr05NV groups and untreated control group received an intraperitoneal dose of cyclophosphamide (Cy-150 mg/kg). Then, the mice were nasally challenged with Sp (107 UFC/mice) on day 3 post-Cy injection. After the pneumococcal challenge, the innate and myelopoietic responses were evaluated. The control group showed a high susceptibility to pneumococcal infection, an impaired innate immune response and a decrease of hematopoietic stem cells (HSCs: Lin-Sca-1+c-Kit+), and myeloid multipotent precursors (MMPs: Gr-1+Ly6G+Ly6C-) in bone marrow (BM). However, lactobacilli treatments were able to significantly increase blood neutrophils and peroxidase-positive cells, while improving cytokine production and phagocytic activity of alveolar macrophages. This, in turn, led to an early Sp lung clearance compared to the control group. Furthermore, Lr05V was more effective than Lr05NV to increase growth factors in BM, which allowed an early HSCs and MMPs recovery with respect to the control group. Both Lr05V and Lr05NV were able to improve BM emergency myelopiesis and protection against respiratory pathogens in mice undergoing chemotherapy.

Counteracting gemcitabine+nab-paclitaxel induced dysbiosis in KRAS wild type and KRASG12D mutated pancreatic cancer in vivo model

Pancreatic cancer (PC) has a very low survival rate mainly due to late diagnosis and refractoriness to therapies. The latter also cause adverse effects negatively affecting the patients' quality of life, often requiring dose reduction or discontinuation of scheduled treatments, compromising the chances of cure. We explored the effects of a specific probiotic blend on PC mice xenografted with KRAS wild-type or KRASG12D mutated cell lines alone or together with gemcitabine+nab-paclitaxel treatment to then assess tumor volume and clinical pathological variables. Beside a semi-quantitative histopathological evaluation of murine tumor and large intestine samples, histochemical and immunohistochemical analyses were carried out to evaluate collagen deposition, proliferation index Ki67, immunological microenvironment tumor-associated, DNA damage markers and also mucin production. Blood cellular and biochemical parameters and serum metabolomics were further analyzed. 16S sequencing was performed to analyze the composition of fecal microbiota. Gemcitabine+nab-paclitaxel treatment impaired gut microbial profile in KRAS wild-type and KRASG12D mice. Counteracting gemcitabine+nab-paclitaxel- induced dysbiosis through the administration of probiotics ameliorated chemotherapy side effects and decreased cancer-associated stromatogenesis. Milder intestinal damage and improved blood count were also observed upon probiotics treatment as well as a positive effect on fecal microbiota, yielding an increase in species richness and in short chain fatty acids producing- bacteria. Mice' serum metabolomic profiles revealed significant drops in many amino acids upon probiotics administration in KRAS wild-type mice while in animals transplanted with PANC-1 KRASG12D mutated all treated groups showed a sharp decline in serum levels of bile acids with respect to control mice. These results suggest that counteracting gemcitabine+nab-paclitaxel-induced dysbiosis ameliorates chemotherapy side effects by restoring a favorable microbiota composition. Relieving adverse effects of the chemotherapy through microbiota manipulation could be a desirable strategy in order to improve pancreatic cancer patients' quality of life and to increase the chance of cure.

The Role of Immunobiotics and Postbiotics in the Recovery of Immune Cell Populations From Respiratory Mucosa of Malnourished Hosts: Effect on the Resistance Against Respiratory Infections

Malnutrition is associated with a state of secondary immunodeficiency, which is characterized by a worsening of the immune response against infectious agents. Despite important advances in vaccines and antibiotic therapies, the respiratory infections are among the leading causes of increased morbidity and mortality, especially in immunosuppressed hosts. In this review, we examine the interactions between immunobiotics-postbiotics and the immune cell populations of the respiratory mucosa. In addition, we discuss how this cross talk affects the maintenance of a normal generation of immune cells, that is crucial for the establishment of protective innate and adaptive immune responses. Particular attention will be given to the alterations in the development of phagocytic cells, T and B lymphocytes in bone marrow, spleen and thymus in immunosuppression state by protein deprivation. Furthermore, we describe our research that demonstrated that the effectiveness of immunobiotics nasal administration in accelerating the recovery of the respiratory immune response in malnourished hosts. Finally, we propose the peptidoglycan from the immunobiotic Lactobacillus rhamnosus CRL1505 as the key cellular component for the effects on mucosal immunity, which are unique and cannot be extrapolated to other L. rhamnosus or probiotic strains. In this way, we provide the scientific bases for its application as a mucosal adjuvant in health plans, mainly aimed to improve the immune response of immunocompromised hosts. The search for safe vaccine adjuvants that increase their effectiveness at the mucosal level is a problem of great scientific relevance today.

Nasal Priming with Lactobacillus rhamnosus CRL1505 Stimulates Mononuclear Phagocytes of Immunocompromised Malnourished Mice: Improvement of Respiratory Immune Response

The effect of Lactobacillus rhamnosus CRL1505 (Lr) on macrophages (Ma) and dendritic cells (DC) in the orchestration of anti-pneumococcal immunity was studied using malnutrition and pneumococcal infection mouse models. Monocytes (Mo), Ma, and DC in two groups of malnourished mice fed with balanced diet (BCD) were studied through flow cytometry; one group was nasally administered with Lr (BCD+Lr group), and the other group was not (BCD group). Well-nourished (WNC) and malnourished (MNC) mice were used as controls.Malnutrition affected the number of respiratory and splenic mononuclear phagocytes. The BCD+Lr treatment, unlike BCD, was able to increase and normalize lung Mo and Ma. The BCD+Lr mice were also able to upregulate the expression of the activation marker MHC II in lung DC and to improve this population showing a more significant effect on CD11b⁺ DC subpopulation. At post-infection, lung Mo values were higher in BCD+Lr mice than in BCD mice and similar to those obtained in WNC group. Although both repletion treatments showed similar values of lung Ma post-infection, the Ma activation state in BCD+Lr mice was higher than that in BCD mice. Furthermore, BCD+Lr treatment was able to normalize the number and activation of splenic Ma and DC after the challenge.Lr administration stimulates respiratory and systemic mononuclear phagocytes. Stimulation of Ma and DC populations would increase the microbicide activity and improve the adaptive immunity through its antigen-presenting capacity. Thus, Lr contributes to improved outcomes of pneumococcal infection in immunocompromised hosts.

Improvement of Myelopoiesis in Cyclophosphamide-Immunosuppressed Mice by Oral Administration of Viable or Non-Viable Lactobacillus Strains

Myelosuppression is the major dose-limiting toxicity of cancer chemotherapy. There have been many attempts to find new strategies that reduce myelosuppression. The dietary supplementation with lactic acid bacteria (LAB) improved respiratory innate immune response and the resistance against respiratory pathogens in immunosupressed hosts. Although LAB viability is an important factor in achieving optimal protective effects, non-viable LAB are capable of stimulating immunity. In this work, we studied the ability of oral preventive administration of viable and non-viable Lactobacillus rhamnosus CRL1505 or L. plantarum CRL1506 (Lr05, Lr05NV, Lp06V or Lp06NV, respectively) to minimize myelosuppressive and immunosuppressive effects derived from chemotherapy. Cyclophosphamide (Cy) impaired steady-state myelopoiesis in lactobacilli-treated and untreated control mice. Lr05V, Lr05NV and Lp06V treatments were the most effective to induce the early recovery of bone marrow (BM) tissue architecture, leukocytes, myeloid, pool mitotic and post-mitotic, peroxidase positive, and Gr-1^Low/High cells in BM. We selected the CRL1505 strain for being the one capable of maintaining its myelopoiesis-enhancing properties in its non-viable form. Although the CRL1505 treatments do not modify the Cy ability to induce apoptosis, both increased the incorporation of BrdU in BM cells. Consequently, Lr05NV and Lr05V treatments were able to promote early recovery of LSK cells (Lin^-Sca-1⁺c-Kit⁺ cells), multipotent progenitors (Lin^-Sca-1⁺c-Kit⁺CD34⁺ cells), and myeloid cells (Gr-1⁺Ly6G⁺Ly6C^- cells) with respect to the untreated Cy control. In addition, these treatments were able to increase the frequency of IL17A-producing innate lymphoid cells in the intestinal lamina propria (IL-17A⁺RORγt⁺CD4^-NKp46⁺ cells) after Cy injection. These results were correlated with an increase in the IL-17A serum levels, a GM-CSF high expression and a CXCL12 lower expression in BM. Therefore, both Lr05V and Lr05NV treatments are able to activate beneficially the IL-17A/GM-CSF axis and accelerate the recovery of Cy-induced immunosuppression by increasing BM myeloid precursors. We demonstrated for the first time the beneficial effect of CRL1505 strain on myelopoiesis affected by a chemotherapeutic drug. Furthermore, Lr05NV could be a good and safe resource for reducing chemotherapy-induced leukopenia. The results are a starting point for future research and open up broad prospects for future applications of the immunobiotics.

Effect of vitamin A deficiency on thymosin-β4 and CD4 concentrations

Vitamins are evaluated for their role in immunity. Recently, vitamin A received a particular attention as a critical micronutrient for regulating immune system. Therefore, the present study aimed to search for new about vitamin A. Forty-eight Egyptian adults aged from 18 to 42 years old from both sexes were subjected to clinical examination and nutrition questionnaire and were screened for vitamin A by using ELISA method. Forty subjects were selected and subdivided into two groups. Group 1 with vitamin A at level >200 µg/dl consists of 10 healthy subjects. Group 2 with vitamin A deficiency at level <50 µg/dl consists of 30 subjects. Tβ4 and CD4 levels were also determined by a commercial ELISA kit. Results showed a significant decrease in serum levels of Tβ4 and CD4 in group 2 than group 1 at P < .003 and P < .019 respectively. Both of Tβ4 and CD4 had positive correlation with vitamin A level at P < .000 and P < .003 respectively as well as with each other at p < .000. We concluded that vitamin A deficiency may be influence the levels of Tβ4 and CD4.

Microbiome-based mechanisms hypothesized to initiate obesity-associated rheumatoid arthritis

Worldwide, the growing obesity pandemic contributes to a range of chronic diseases. Recent epidemiological studies have suggested an association between obesity and the development of rheumatoid arthritis (RA), particularly among young women, whereby pro-inflammatory effects of adipokines provide one explanatory hypothesis. Yet, recent clinical and laboratory-based studies provide emerging evidence indicating microbiome involvement in RA initiation and development, including anti-citrullinated antibody formation and Th17 cell activation. Obesity and RA-associated microbiome alteration might provide a plausible link to address the impact of obesity to RA pathogenesis. The microbiome's influence on RA development - at mucosal as well as articular sites - and relevant pathophysiological mechanisms regarding obesity's association with RA are presented herein to discuss this hypothesis and aid understanding of obesity's role in RA development.

Advances in Probiotic Regulation of Bone and Mineral Metabolism

Probiotics have been consumed by humans for thousands of years because they are beneficial for long-term storage of foods and promote the health of their host. Ingested probiotics reside in the gastrointestinal tract where they have many effects including modifying the microbiota composition, intestinal barrier function, and the immune system which result in systemic benefits to the host, including bone health. Probiotics benefit bone growth, density, and structure under conditions of dysbiosis, intestinal permeability, and inflammation (recognized mediators of bone loss and osteoporosis). It is likely that multiple mechanisms are involved in mediating probiotic signals from the gut to the bone. Studies indicate a role for the microbiota (composition and activity), intestinal barrier function, and immune cells in the signaling process. These mechanisms are not mutually exclusive, but rather, may synergize to provide benefits to the skeletal system of the host and serve as a starting point for investigation. Given that probiotics hold great promise for supporting bone health and are generally regarded as safe, future studies identifying mechanisms are warranted.

Are the immunomodulatory properties of Lactobacillus rhamnosus CRL1505 peptidoglycan common for all Lactobacilli during respiratory infection in malnourished mice?

Previously, we reported that Lactobacillus rhamnosus CRL1505 peptidoglycan (PG05) improves the innate immune response in immunocompromised-malnourished mice after Streptococcus pneumoniae infection. This study extends those previous findings by demonstrating that the dietary recovery of malnourished mice with nasal administration of PG05 improves not only the innate immune response but the respiratory and systemic adaptive humoral response as well. PG05 enhanced the Th2 response, the recovery of B cells, and the concentration and opsonophagocytic activity of anti-pneumococcal antibodies. In addition, by performing comparative studies with the peptidoglycans from lactobacilli of the same species (L. rhamnosus CRL534) or with similar immunomodulatory properties (L. plantarum CRL1506), we demonstrated here that PG05 has unique immunomodulatory properties that cannot be extended to peptidoglycans from other probiotic strains. However, the knowledge of the molecular characteristics of PG05 is indispensable to understand immunomodulatory abilities of L. rhamnosus CRL1505.

Gut microbiota alterations and dietary modulation in childhood malnutrition - The role of short chain fatty acids

The gut microbiome affects the health status of the host through different mechanisms and is associated with a wide variety of diseases. Both childhood undernutrition and obesity are linked to alterations in composition and functionality of the gut microbiome. One of the possible mechanisms underlying the interplay between microbiota and host metabolism is through appetite-regulating hormones (including leptin, ghrelin, glucagon-like peptide-1). Short chain fatty acids, the end product of bacterial fermentation of non-digestible carbohydrates, might be able to alter energy harvest and metabolism through enteroendocrine cell signaling, adipogenesis and insulin-like growth factor-1 production. Elucidating these mechanisms may lead to development of new modulation practices of the gut microbiota as a potential prevention and treatment strategy for childhood malnutrition. The present overview will briefly outline the gut microbiota development in the early life, gut microbiota alterations in childhood undernutrition and obesity, and whether this relationship is causal. Further we will discuss possible underlying mechanisms in relation to the gut-brain axis and short chain fatty acids, and the potential of probiotics, prebiotics and synbiotics for modulating the gut microbiota during childhood as a prevention and treatment strategy against undernutrition and obesity.

Lactobacillus rhamnosus CRL1505 nasal administration improves recovery of T-cell mediated immunity against pneumococcal infection in malnourished mice

Immunobiotic lactic acid bacteria have become an interesting alternative for the prevention of respiratory infections. Previously, we demonstrated that the nasal administration of Lactobacillus rhamnosus CRL1505, during repletion of malnourished mice, resulted in diminished susceptibility to the challenge with the respiratory pathogen Streptococcus pneumoniae. Considering the known alterations induced by malnutrition on T lymphocytes and the importance of this cell population on the protection against respiratory pathogens, we aimed to study the effect of L. rhamnosus CRL1505 nasal administration on the recovery of T cell-mediated defences against pneumococcal infection in malnourished mice under nutritional recovery. Malnourished mice received a balanced conventional diet (BCD) for seven days or BCD for seven days with nasal L. rhamnosus CRL1505 supplementation during last two days of the treatment. After the treatments mice were infected with S. pneumoniae. Flow cytometry studies were carried out in bone marrow, thymus, spleen and lung to study T cells, and Th1/Th2 cytokine profiles were determined in broncho-alveolar lavages and serum. The administration of CRL1505 strain to malnourished mice under recovery reduced quantitative and qualitative alterations of CD4+ T cells in the bone marrow, thymus, spleen and lung induced by malnutrition. In addition, CRL1505 treatment augmented Th2-cytokines (interleukin 10 and 4) in respiratory and systemic compartments after pneumococcal infection. These results show that modulation of CD4+ T lymphocytes induced by L. rhamnosus CRL1505 has an important role in the beneficial effect induced by this strain on the recovery of malnourished mice. These data also indicate that nasally administered L. rhamnosus CRL1505 may represent a non-invasive alternative to modulate and improve the T cell-mediated immunity against respiratory pathogens in immunocompromised malnourished hosts.

The Role of Microbiota and Immunobiotics in Granulopoiesis of Immunocompromised Hosts

The number of granulocytes is maintained by a regulated balance between granulopoiesis in the bone marrow and clearance and destruction in peripheral tissues. Granulopoiesis plays a fundamental role in the innate immune response. Therefore, factors affecting the normal granulopoiesis lead to alterations in innate defenses and reduce the resistance against infections. In this study, we give a description on recent advances regarding the molecular and cellular events that regulate steady-state and emergency granulopoiesis, which are crucial processes for the generation of protective innate immune responses. Particular attention will be given to emergency granulopoiesis alterations in immunosuppression states caused by malnutrition and chemotherapy. The role of microbiota in maintaining a steady-state granulopoiesis and the immunological mechanisms involved are also discussed. Moreover, we describe the findings of our laboratory demonstrating that the dietary supplementation with immunobiotics is an interesting alternative to improve steady-state and emergency granulopoiesis, the respiratory innate immune response, and the resistance against respiratory pathogens in immunocompromised hosts.

Probiotics and Disease: A Comprehensive Summary-Part 4, Infectious Diseases

This article series provides a literature review of the disease-specific probiotic strains studied in published clinical trials in humans and animals. The goal of the series is to provide clinically useful tools. The table design allows for quick access to supportive data and will be helpful as a guide for both researchers and clinicians. The first article (part 1) focused on mental health and neurological conditions and the second article (part 2) explored cultured and fermented foods that are commonly available in the United States. The third article (part 3) explored the relationship between bacterial strains and 2 of the most prevalent diseases we have in modern society, cardiometabolic disease and fatigue syndromes. This fourth article (part 4) elucidates the role of the microbiome in infectious diseases. Future articles will review conditions related to infections of the upper respiratory system and ear, nose, and throat; autoimmunity and dermatological conditions; cancer; and gastrointestinal and genitourinary, followed by an article focused on probiotic supplements. This literature review is specific to disease condition, probiotic classification, and individual strain.

Immunomodulatory effect of a formula developed from American ginseng and Chinese jujube extracts in mice

BACKGROUND

American ginseng (Panax quinquefolius L.) and Chinese jujube (Zizyphus jujuba Mill.) are commonly used in traditional Chinese medicine to enhance immune function.

OBJECTIVE

The present study aimed to develop one Chinese prescription, Shenzao Cha (SZC), consisting of American ginseng and Chinese jujube, and systematically investigate its immunomodulation in healthy ICR mice.

METHODS

Normal ICR mice received intragastric administration of SZC (1.3, 2.6, and 5.2 g raw material/kg body weight) once daily for four weeks, while a control group received the same amount of sterile water.

RESULTS

SZC significantly increased the spleen and thymus indices and T-lymphocyte proliferation, while the T-lymphocyte proliferation in the 5.2 g/kg group was 1.4-fold higher than that in the control. Further, 1.3 g/kg SZC could markedly improve hemolytic activity by 25.2%, and 2.6 g/kg SZC increased the NK cell activity by 78.6% relative to the control. In addition, the activities of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase), that participated in modulating oxidative stress, were significantly increased in the liver, spleen, thymus, and serum, while the contents of malondialdehyde were dramatically decreased.

CONCLUSIONS

SZC exhibited potent immunomodulatory effects on innate and adaptive immunity in healthy ICR mice, as well as potential antioxidant activity for prevention of oxidative stress, which was suggested to partly contribute to the immune enhancement.

Oral administration of an aqueous extract from the oyster mushroom Pleurotus ostreatus enhances the immunonutritional recovery of malnourished mice

Mushroom nutriceutical components have lately attracted interest for developing immunonutritional support. However, there is relatively little information pertaining to the use of mushroom preparations for modulating the metabolic and immunological disorders associated to malnutrition. This study was aimed to evaluate the effects of oral administration of an aqueous extract (CW-P) from Pleurotus ostreatus on the recovery of biochemical and immunological functions of malnourished mice. 8-week old female BALB/c mice were starved for 3days and then refed with commercial diet supplemented with or without CW-P (100mg/kg) for 8days. Regardless of the diet used during refeeding, animal body weights and serum protein concentrations did not differ between groups. Oral treatment with CW-P normalized haemoglobin levels, liver arginase and gut mucosal weight. CW-P increased total liver proteins and also DNA and protein contents in gut mucosa. Pleurotus extract provided benefits in terms of macrophages activation as well as in haemopoiesis, as judged by the recovery of bone marrow cells and leukocyte counts. Moreover, CW-P stimulated humoral immunity (T-dependent and T non-dependent antibodies responses) compared to non-supplemented mice. CW-P extract from the oyster mushroom can be used to develop specific food or nutritional supplement formulations with potential clinical applications in the immunotherapy.

Prebiotic and Probiotic Regulation of Bone Health: Role of the Intestine and its Microbiome

Recent advances in our understanding of how the intestinal microbiome contributes to health and disease have generated great interest in developing strategies for modulating the abundance of microbes and/or their activity to improve overall human health and prevent pathologies such as osteoporosis. Bone is an organ that the gut has long been known to regulate through absorption of calcium, the key bone mineral. However, it is clear that modulation of the gut and its microbiome can affect bone density and strength in a variety of animal models (zebrafish, rodents, chicken) and humans. This is demonstrated in studies ablating the microbiome through antibiotic treatment or using germ-free mouse conditions as well as in studies modulating the microbiome activity and composition through prebiotic and/or probiotic treatment. This review will discuss recent developments in this new and exciting area.

The influence of vitamin B12 supplementation on the level of white blood cells and lymphocytes phenotype in rats fed a low-protein diet

Protein malnutrition has a negative effect on body composition and some blood parameters, especially in the young growing organism. One of nutritional factors which could protect against negative consequences of protein deficiency may be B group vitamins. The aim of the study was to investigate the effect of vitamin B12 supplementation on the immune system in rats fed a standard and a low-protein diet. Rats were fed a control (20% of energy from protein) or a protein-deficient diet (4.5% of energy from protein). Half of animals in each group were additionally supplemented with vitamin B12 (300% of the daily intake). The white blood cells analysis and lymphocytes immunophenotyping (number and percentage) were performed. Low-protein diets caused disturbances in WBC and lymphocyte subpopulations in both short- (30-day) as well as long-term periods (90-day). Vitamin B12 supplementation significantly reduced the negative impact of protein malnutrition after 30 days, however had no effect on long-term malnutrition. Furthermore, vitamin B12 addition in rats fed a control diet did not affect the studied parameters. This observation opens the promise of use of vitamin B12 supplementation to improve immune system parameters in protein malnourished organisms.

Probiotic Lactobacillus strains protect against myelosuppression and immunosuppression in cyclophosphamide-treated mice

This work evaluated the capacity of two probiotic strains, Lactobacillus casei CRL431 and Lactobacillus rhamnosus CRL1506, to protect against myelosuppression and immunosuppression in cyclophosphamide (Cy)-treated mice. Changes in mature granulocytes and progenitor cells in bone marrow (BM) and blood were studied. In addition, the ability of probiotics to accelerate the recovery of the immune response against the opportunistic pathogen Candida albicans was evaluated. We demonstrated for the first time that the preventive treatment with immunomodulatory lactobacilli such as L. casei CRL431 or L. rhamnosus CRL1506 was able to increase immature myeloid progenitors in the BM, allowing an early recovery of myeloid cells after Cy administration. Probiotic lactobacilli were also capable to induce an early recovery of neutrophils in blood, improve phagocytic cells recruitment to infectious sites and increase the resistance against the opportunistic pathogen C. albicans. Although deeper studies regarding the cellular and molecular mechanisms of probiotic actions are needed, these findings support the idea that strains like CRL431 and CRL1506 may accelerate the recovery of Cy-caused immunosuppression by immunopotentiating myeloid cells. Then, probiotic lactobacilli have the potential to be used as alternatives for lessening chemotherapy-induced immunosuppression in cancer patients.

Dietary supplementation with Lactobacilli improves emergency granulopoiesis in protein-malnourished mice and enhances respiratory innate immune response

This work studied the effect of protein malnutrition on the hemato-immune response to the respiratory challenge with Streptococcus pneumoniae and evaluated whether the dietary recovery with a probiotic strain has a beneficial effect in that response. Three important conclusions can be inferred from the results presented in this work: a) protein-malnutrition significantly impairs the emergency myelopoiesis induced by the generation of the innate immune response against pneumococcal infection; b) repletion of malnourished mice with treatments including nasally or orally administered Lactobacillus rhamnosus CRL1505 are able to significantly accelerate the recovery of granulopoiesis and improve innate immunity and; c) the immunological mechanisms involved in the protective effect of immunobiotics vary according to the route of administration. The study demonstrated that dietary recovery of malnourished mice with oral or nasal administration of L. rhamnosus CRL1505 improves emergency granulopoiesis and that CXCR4/CXCR12 signaling would be involved in this effect. Then, the results summarized here are a starting point for future research and open up broad prospects for future applications of probiotics in the recovery of immunocompromised malnourished hosts.

Lactobacillus rhamnosus CRL1505 beneficially modulates the immuno-coagulative response after pneumococcal infection in immunocompromised malnourished mice

This work evaluated the effect of orally or nasally administered Lactobacillus rhamnosus CRL1505 on the resistance of immunocompromised protein-malnourished mice to pneumococcal infection. In particular, we aimed to gain knowledge of the mechanism involved in the immunomodulatory effect of L. rhamnosus CRL1505 in malnourished hosts by evaluating its impact on the immuno-coagulative response. Malnutrition significantly increased lung tissue damage caused by Streptococcus pneumoniae infection. Lung damage was associated with a deregulated activation of coagulation and an altered inflammatory response. Pneumococcal colonization of lung and bacteremia were significantly reduced (p < 0.05) in malnourished mice receiving the CRL1505 strain. Moreover, mice repleted with supplemental L. rhamnosus CRL1505 showed the least alteration of the alveolar–capillary barrier and cell damage in lungs after the infectious challenge, especially when the CRL1505 strain was administered by nasal route. Besides, mice treated with L. rhamnosus CRL1505 showed an improved respiratory innate immune response and a lower activation of coagulation. The results of this work indicate that L. rhamnosus CRL1505 is able to beneficially modulate the inflammation–coagulation interaction after respiratory infections in malnourished hosts.

Chlorella vulgaris treatment ameliorates the suppressive effects of single and repeated stressors on hematopoiesis

The reports regarding the mutual influence between the central nervous system and the immune system constitute a vast and somewhat controversial body of literature. Stress is known to disturb homeostasis, impairing immunological functions. In this study, we investigated the hematopoietic response of Chlorella vulgaris (CV)-treated mice exposed to single (SST) and repeated stress (RST). We observed a reduction in the numbers of hematopoietic progenitors (HP) in the bone marrow and long-term bone marrow cultures (LTBMC) using flow cytometry and a coinciding decrease in the number of granulocyte-macrophage colonies (CFU-GM) after treatment with both stressors, but SST caused a more profound suppression. We observed a proportional increase in the colony-stimulating activity (CSA) of the serum of animals subjected to SST or RST. In the bone marrow, SST and RST induced a decrease in both mature myeloid and lymphoid populations but did not affect pluripotent hematopoietic progenitors (Lin(-)Sca-1(+)c-kit(+), LSK), and again, a more profound suppression was observed after SST. We further quantified the levels of interleukin-1α (IL-1α) and interleukin-6 (IL-6) and the number of myeloid cells in LTBMC. Both SST and RST reduced the levels of these cytokines to similar degrees. The myeloid population was also reduced in LTBMC, and SST induced a more intense suppression. Importantly, CV treatment prevented the changes produced by SST and RST in all of the parameters evaluated. Together, our results suggest that CV treatment is an effective tool for the prophylaxis of myelosuppression caused by single or repeated stressors.

Nasally administered Lactobacillus rhamnosus accelerate the recovery of humoral immunity in B lymphocyte-deficient malnourished mice

The ability of nasally administered Lactobacillus rhamnosus CRL1505 to accelerate the recovery of respiratory B cell-mediated immunity against pneumococcal infection in replete malnourished mice was evaluated. Weaned mice were malnourished after consumption of a protein-free diet for 21 d. Malnourished mice were fed a balanced conventional diet (BCD) for 7 d (BCD group) or a BCD for 7 d with supplemental L. rhamnosus CRL1505 by the nasal route during the last 2 d (BCD+Lr group). Nonreplete malnourished and normal mice were used as the malnourished (MNC) and the well-nourished (WNC) control groups, respectively. Mice were challenged with Streptococcus pneumoniae at the end of each dietary treatment. The immune response was studied before the challenge and at different times postinfection. The MNC mice had less resistance to pneumococcal infection, fewer mature and immature B cells in lung and spleen, and a reduced production of specific antibodies compared with WNC mice. The BCD treatment did not induce a complete normalization of the number B cell populations and antibody amounts. However, the BCD+Lr group had normal numbers of spleen and lung B cells. Moreover, the BCD+Lr mice had a significantly lower susceptibility to S. pneumoniae infection and higher amounts of anti-pneumococcal antibodies. Although further studies are necessary to clarify the effect of malnutrition and nasally administered lactobacilli in other immune cell populations involved in the protection against respiratory pathogens, this work gives evidence of the importance of using nasal priming with probiotics to accelerate the recovery of respiratory immunity in immunocompromised malnourished hosts.