Modulatory activity of a Lactobacillus casei strain on 1,2-dimethylhydrazine-induced genotoxicity in rats

Postbiotics as Potential Detoxification Tools for Mitigation of Pesticides

Pesticides possess a pivotal role in the realm of agriculture and food manufacturing, as they effectively manage the proliferation of weeds, insects, plant pathogens, and microbial contaminations. They are valuable in some ways, but if misused, they can cause health issues like cancer, reproductive toxicity, neurological illnesses, and endocrine system disturbances. In this regard, practical methods for reducing pesticide residue in food should be used. For reducing pesticide residue in food processing, some strategies have been suggested. Recent research has been done on detoxification processes, including microorganisms like probiotics and their metabolites. The term "postbiotics" describes soluble substances, such as peptides, enzymes, teichoic acids, muropeptides generated from peptidoglycans, polysaccharides, proteins, and organic acids that are secreted by living bacteria or released after bacterial lysis. Due to their distinct chemical makeup, safe dosage guidelines, lengthy shelf lives, and presence of various signaling molecules that may have antioxidant, anti-inflammatory, anti-obesogenic, immunomodulatory, anti-hypertensive, and immunomodulatory effects, these postbiotics have attracted interest. They also can detoxify heavy metals, mycotoxins, and pesticides. Hydrolytic enzymes have been proposed as a potential mechanism for pesticide degradation. Postbiotics can also reduce reactive oxygen species production, enhance gastrointestinal barrier function, reduce inflammation, and modulate host xenobiotic metabolism. This review highlights pesticide residues in food products, definitions and safety aspect of postbiotics, as well as their biological role in detoxification of pesticides and the protective role of these compounds against the adverse effects of pesticides.

[Assessment of the in vitro effect of intra and extracellular extracts of Lactobacillus against genotoxicity and oxidative stress caused by acrylamide]

Introduction

Introduction: acrylamide is formed by the Maillard reaction and is found in many food products subjected to thermal processes, generating genotoxicity and DNA damage. Studies have reported that lactobacilli have the ability to generate compounds with antioxidant, antigenotoxic and antimutagenic activity, which is why the present work aims to evaluate the effect of Lactobacillus strains and their intra and extracellular extracts against genotoxicity and oxidative stress as caused by acrylamide. Methods: a strain of Lactobacillus casei Shirota and a strain of Lactobacillus reuteri NRRL B-14171 were used, both were cultured in MRS broth and subjected to mechanical and enzymatic treatments to obtain extra and intracellular extracts. Lymphocytes were cultured in RPMI medium. Lipid peroxidation was evaluated by TBARS and the antioxidant capacity was measured in the extra and intracellular extracts with the ABTS technique, also using a strain of Saccharomyces cerevisiae RC 212 as a model. The reduction of lipid peroxidation in lymphocytes was measured by TBARS and the reduction of genotoxicity by reducing the formation of micronuclei in lymphocytes. Results: both strains evaluated, as well as their intra and extracellular extracts, showed the ability to counteract oxidative stress and genotoxicity caused by acrylamide. Conclusion: the results found suggest that the use of intra and extracellular extracts of both strains could be an alternative to reduce the effects of genotoxicity and oxidative stress caused by acrylamide without the need for a viable structure.

Microbial Detoxification of Residual Pesticides in Fermented Foods: Current Status and Prospects

The treatment of agricultural areas with pesticides is an indispensable approach to improve crop yields and cannot be avoided in the coming decades. At the same time, significant amounts of pesticides remain in food and their ingestion causes serious damage such as neurological, gastrointestinal, and allergic reactions; cancer; and even death. However, during the fermentation processing of foods, residual amounts of pesticides are significantly reduced thanks to enzymatic degradation by the starter and accompanying microflora. This review concentrates on foods with the highest levels of pesticide residues, such as milk, yogurt, fermented vegetables (pickles, kimchi, and olives), fruit juices, grains, sourdough, and wines. The focus is on the molecular mechanisms of pesticide degradation due to the presence of specific microbial species. They contain a unique genetic pool that confers an appropriate enzymological profile to act as pesticide detoxifiers. The prospects of developing more effective biodetoxification strategies by engaging probiotic lactic acid bacteria are also discussed.

Probiotics as a biological detoxification tool of food chemical contamination: A review

Nowadays, people are exposed to diverse environmental and chemical pollutants produced by industry and agriculture. Food contaminations such as persistent organic pollutants (POPs), heavy metals, and mycotoxins are a serious concern for global food safety with economic and public health implications especially in the newly industrialized countries (NIC). Mounting evidence indicates that chronic exposure to food contaminants referred to as xenobiotics exert a negative effect on human health such as inflammation, oxidative stress, and intestinal disorders linked with perturbation of the composition and metabolic profile of the gut microflora. Although the physicochemical technologies for food decontamination are utilized in many cases but require adequate conditions which are often not feasible to be met in many industrial sectors. At present, one promising approach to reduce the risk related to the presence of xenobiotics in foodstuffs is a biological detoxification done by probiotic strains and their enzymes. Many studies confirmed that probiotics are an effective, feasible, and inexpensive tool for preventing xenobiotic-induced dysbiosis and alleviating their toxicity. This review aims to summarize the current knowledge of the direct mechanisms by which probiotics can influence the detoxification of xenobiotics. Moreover, probiotic-xenobiotic interactions with the gut microbiota and the host response were also discussed.

Modulating the Microbiota as a Therapeutic Intervention for Type 2 Diabetes

Mounting evidence suggested that the gut microbiota has a significant role in the metabolism and disease status of the host. In particular, Type 2 Diabetes (T2D), which has a complex etiology that includes obesity and chronic low-grade inflammation, is modulated by the gut microbiota and microbial metabolites. Current literature supports that unbalanced gut microbial composition (dysbiosis) is a risk factor for T2D. In this review, we critically summarize the recent findings regarding the role of gut microbiota in T2D. Beyond these associative studies, we focus on the causal relationship between microbiota and T2D established using fecal microbiota transplantation (FMT) or probiotic supplementation, and the potential underlying mechanisms such as byproducts of microbial metabolism. These microbial metabolites are small molecules that establish communication between microbiota and host cells. We critically summarize the associations between T2D and microbial metabolites such as short-chain fatty acids (SCFAs) and trimethylamine N-Oxide (TMAO). Additionally, we comment on how host genetic architecture and the epigenome influence the microbial composition and thus how the gut microbiota may explain part of the missing heritability of T2D found by GWAS analysis. We also discuss future directions in this field and how approaches such as FMT, prebiotics, and probiotics supplementation are being considered as potential therapeutics for T2D.

Can probiotics win the battle against environmental endocrine disruptors?

Compounds that have negative effects on the endocrine system are called endocrine disrupting compounds (EDCs). There are several different types of compounds, with several different usage areas in the environment, which can be classified as EDCs. These chemicals have a wide range of negative health effects in organisms, depending on their target hormone system. EDCs are among the most popular topics of scientific research, as they are widely used and organisms are frequently exposed to these chemicals. There are various exposure routes for EDCs, such as oral, inhalation and dermal exposure. Parabens, phenolic compounds, phthalates, and pesticides are the most common EDCs. Nowadays, intestinal microorganism distribution, probiotics, and food supplements that regulate these microorganisms and their protective effects against various harmful chemicals attract attention. For this reason, many studies have been carried out in this field and certain diet schemes have been created according to the results of these studies. In fact, probiotics are preferred in order to reduce and eliminate the negative effects of harmful chemicals and to ensure that the organism reacts strongly in these conditions. In this review, we will focus on EDCs, their health effects and positive effects of probiotics on EDCs exposure conditions.

Preclinical and clinical relevance of probiotics and synbiotics in colorectal carcinogenesis: a systematic review

CONTEXT

Recent evidence suggests that modulation of the gut microbiota may help prevent colorectal cancer.

OBJECTIVE

The aim of this systematic review was to investigate the role of probiotics and synbiotics in the prevention of colorectal cancer and to clarify potential mechanisms involved.

DATA SOURCES

The PubMed, ScienceDirect, and LILACS databases were searched for studies conducted in humans or animal models and published up to August 15, 2018.

STUDY SELECTION

Clinical trials and placebo-controlled experimental studies that evaluated the effects of probiotics and synbiotics in colorectal cancer and cancer associated with inflammatory bowel disease were included. Of 247 articles identified, 31 remained after exclusion criteria were applied. A search of reference lists identified 5 additional studies, for a total of 36 included studies.

DATA EXTRACTION

Two authors independently assessed risk of bias of included studies and extracted data. Data were pooled by type of study, ie, preclinical or clinical.

RESULTS

The results showed positive effects of probiotics and synbiotics in preventing colorectal cancer. The main mechanisms identified were alterations in the composition and metabolic activity of the intestinal microbiota; reduction of inflammation; induction of apoptosis and inhibition of tumor growth; modulation of immune responses and cell proliferation; enhanced function of the intestinal barrier; production of compounds with anticarcinogenic activity; and modulation of oxidative stress.

CONCLUSIONS

Probiotics or synbiotics may help prevent colorectal cancer, but additional studies in humans are required to better inform clinical practice.

A Review on Gut Remediation of Selected Environmental Contaminants: Possible Roles of Probiotics and Gut Microbiota

Various environmental contaminants including heavy metals, pesticides and antibiotics can contaminate food and water, leading to adverse effects on human health, such as inflammation, oxidative stress and intestinal disorder. Therefore, remediation of the toxicity of foodborne contaminants in human has become a primary concern. Some probiotic bacteria, mainly Lactobacilli, have received a great attention due to their ability to reduce the toxicity of several contaminants. For instance, Lactobacilli can reduce the accumulation and toxicity of selective heavy metals and pesticides in animal tissues by inhibiting intestinal absorption of contaminants and enhancing intestinal barrier function. Probiotics have also shown to decrease the risk of antibiotic-associated diarrhea possibly via competing and producing antagonistic compounds against pathogenic bacteria. Furthermore, probiotics can improve immune function by enhancing the gut microbiota mediated anti-inflammation. Thus, these probiotic bacteria are promising candidates for protecting body against foodborne contaminants-induced toxicity. Study on the mechanism of these beneficial bacterial strains during remediation processes and particularly their interaction with host gut microbiota is an active field of research. This review summarizes the current understanding of the remediation mechanisms of some probiotics and the combined effects of probiotics and gut microbiota on remediation of foodborne contaminants in vivo.

Bacterial Composition, Genotoxicity, and Cytotoxicity of Fecal Samples from Individuals Consuming Omnivorous or Vegetarian Diets

This study analyzes the composition of viable fecal bacteria and gut toxicology biomarkers of 29 healthy volunteers, who followed omnivorous, lacto-ovo-vegetarian, or vegan diets. In particular, the research was focused on the prevalence of some representative viable bacteria from the four dominant phyla (Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria) commonly present in human feces, in order to evaluate the relationship between microorganisms selected by the habitual dietary patterns and the potential risk due to fecal water (FW) genotoxicity and cytotoxicity, considered as biomarkers for cancer risk and protective food activity. The relative differences of viable bacteria among dietary groups were generally not statistically significant. However, compared to omnivores, lacto-ovo-vegetarians showed low levels of total anaerobes. Otherwise, vegans showed total anaerobes counts similar to those of omnivores, but with lower number of bifidobacteria and the highest levels of bacteria from the Bacteroides–Prevotella genera. FW genotoxicity of lacto-ovo-vegetarians resulted significantly lower either in relation to that of omnivores and vegans. Lacto-ovo-vegetarians also showed the lowest levels of cytotoxicity, while the highest were found for vegans. These results highlighted that lacto-ovo-vegetarian diet was particularly effective in a favorable modulation of microbial activity, thus contributing to a significant reduction of the genotoxic and cytotoxic risk in the gut.

Administration of Lactobacillus casei and Bifidobacterium bifidum Ameliorated Hyperglycemia, Dyslipidemia, and Oxidative Stress in Diabetic Rats

BACKGROUND

The present work was planned to evaluate the antihyperglycemic, lipid-lowering, and antioxidant effect of Lactobacillus casei and Bifidobacterium bifidum in streptozotocin (STZ)-induced diabetic rats.

METHODS

Single daily dose of 1 × 10(7) cfu/ml of L. casei and B. bifidum alone and in combination of both was given to Wistar rats orally by gavaging for 28 days. Glucose tolerance test, fasting blood glucose (FBG), lipid profile, and glycosylated hemoglobin (HbA1c) were measured from blood. Glycogen from thigh muscles and liver and oxidative stress parameters from pancreas were analyzed.

RESULTS

Administration of L. casei and B. bifidum alone and in combination of both to diabetic rats decreased serum FBG (60.47%, 55.89%, and 56.49%, respectively), HbA1c (28.11%, 28.61%, and 28.28%), total cholesterol (171.69%, 136.47%, and 173.58%), triglycerides (9.935%, 8.58%, and 7.91%), low-density lipoproteins (53.27%, 53.35%, and 52.91%) and very low-density lipoproteins (10%, 8.58%, and 11.15%, respectively) and increased high-density lipoproteins (13.73%, 15.47%, and 15.47%), and insulin (19.50%, 25.80%, and 29.47%, respectively). The treatment also resulted in increase in muscle (171.69%, 136.47%, and 173.58%) and liver (25.82%, 6.63%, and 4.02%) glycogen level. The antioxidant indexes in pancreas of diabetic rats returned to normal level with reduction in lipid peroxidation (30.89%, 46.46%, and 65.36%) and elevation in reduced glutathione (104.5%, 161.34%, and 179.04%), superoxide dismutase (38.65%, 44.32%, and 53.35%), catalase (13.08%, 27%, and 31.52%), glutathione peroxidase (55.56%, 72.23%, and 97.23%), glutathione reductase (49.27%, 88.40%, and 110.86%), and glutathione-S-transferase (140%, 220%, and 246.6%, respectively) on treatment with L. casei, B. bifidum, and combination treatment.

CONCLUSIONS

Administration of L. casei and B. bifidum alone and in combination of both ameliorated hyperglycemia, dyslipidemia, and oxidative stress in STZ-induced diabetic Wistar rats.

Probiotic lactobacilli: a potential prophylactic treatment for reducing pesticide absorption in humans and wildlife

Numerous pesticides are used in agriculture, gardening, and wildlife-control. Despite their intended toxicity to pests, these compounds can also cause harm to wildlife and humans due to their ability to potentially bioaccumulate, leach into soils, and persist in the environment. Humans and animals are commonly exposed to these compounds through agricultural practices and consumption of contaminated foods and water. Pesticides can cause a range of adverse effects in humans ranging from minor irritation, to endocrine or nervous system disruption, cancer, or even death. A convenient and cost-effective method to reduce unavoidable pesticide absorption in humans and wildlife could be the use of probiotic lactobacilli. Lactobacillus is a genus of Gram-positive gut commensal bacteria used in the production of functional foods, such as yoghurt, cheese, sauerkraut and pickles, as well as silage for animal feed. Preliminary in vitro experiments suggested that lactobacilli are able to degrade some pesticides. Probiotic Lactobacillus rhamnosus GR-1-supplemented yoghurt reduced the bioaccumulation of mercury and arsenic in pregnant women and children. A similar study is warranted to test if this approach can reduce pesticide absorption in vivo, given that the lactobacilli can also attenuate reactive oxygen production, enhance gastrointestinal barrier function, reduce inflammation, and modulate host xenobiotic metabolism.

Food borne yeasts as DNA-bioprotective agents against model genotoxins

Yeasts isolated from Italian beverages and foods (wine and cheeses) were identified as Saccharomyces cerevisiae and Debaryomyces hansenii by sequencing the D1/D2 domain of the 26S rRNA gene and differentiated, at strain level, by microsatellite PCR fingerprinting and RAPD-PCR. All the strains showed antioxidant activity, as demonstrated by their ability to scavenge the free radical diphenyl-1-picrylhydrazyl (DPPH). Furthermore, tested strains revealed high in vitro inhibitory activity against two model genotoxins, 4-nitroquinoline-1-oxide (4-NQO) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), as showed by short-term methods with different target cells: SOS-Chromotest with Escherichia coli PQ37 and Comet assay with HT-29 enterocytes. High inhibitory activity towards 4-NQO was associated with cell viability, while heat-inactivated cells showed a reduced antigenotoxic capability. Surprisingly, high inhibition of MNNG genotoxicity was observed even with heat-treated cells. Moreover, the strains able to inhibit the genotoxins induced some changes in the spectroscopic properties of the original compound. This result perfectly agrees with the information obtained by the two bioassays. Interestingly, strains characterized for antioxidant and antigenotoxic properties, also presented acid-bile tolerance, indicating that food autochthonous yeasts could be expected to reach gut in viable form and thus prevent genotoxin DNA damage in situ.