scholarly journals Probiotics: A Dietary Factor to Modulate the Gut Microbiome, Host Immune System, and Gut–Brain Interaction

2020 ◽  
Vol 8 (9) ◽  
pp. 1401 ◽  
Author(s):  
Tetsuji Hori ◽  
Kazunori Matsuda ◽  
Kenji Oishi
Keyword(s):  
Gastrointestinal Tract ◽  
Animal Studies ◽  
Endocrine Cells ◽  
Short Chain Fatty Acids ◽  
Fermented Milk ◽  
Research Area ◽  
Host Cells ◽  
Host Immune System ◽  
Human Gastrointestinal Tract

Various benefits of probiotics to the host have been shown in numerous human clinical trials. These organisms have been proposed to act by improving the balance of the gut microbiota and enhancing the production of short-chain fatty acids, as well as by interacting with host cells in the gastrointestinal tract, including immune cells, nerve cells, and endocrine cells. Although the stimulation of host cells by probiotics and subsequent signaling have been explained by in vitro experiments and animal studies, there has been some skepticism as to whether probiotics can actually interact with host cells in the human gastrointestinal tract, where miscellaneous indigenous bacteria coexist. Most recently, it has been shown that the ileal microbiota in humans after consumption of a fermented milk is occupied by probiotics for several hours, indicating that there is adequate opportunity for the ingested strain to stimulate the host cells continuously over a period of time. As the dynamics of ingested probiotics in the human gastrointestinal tract become clearer, further progress in this research area is expected to elucidate their behavior within the tract, as well as the mechanism of their physiological effects on the host.

scholarly journals Oxidative Stress as a Possible Target in the Treatment of Toxoplasmosis: Perspectives and Ambiguities

2021 ◽  
Vol 22 (11) ◽  
pp. 5705
Author(s):  
Karolina Szewczyk-Golec ◽  
Marta Pawłowska ◽  
Roland Wesołowski ◽  
Marcin Wróblewski ◽  
Celestyna Mila-Kierzenkowska
Keyword(s):  
Oxidative Stress ◽  
Animal Studies ◽  
Treatment Options ◽  
Natural Antioxidants ◽  
Redox Status ◽  
Host Cells ◽  
Common Disease ◽  
Parasite Viability

Toxoplasma gondii is an apicomplexan parasite causing toxoplasmosis, a common disease, which is most typically asymptomatic. However, toxoplasmosis can be severe and even fatal in immunocompromised patients and fetuses. Available treatment options are limited, so there is a strong impetus to develop novel therapeutics. This review focuses on the role of oxidative stress in the pathophysiology and treatment of T. gondii infection. Chemical compounds that modify redox status can reduce the parasite viability and thus be potential anti-Toxoplasma drugs. On the other hand, oxidative stress caused by the activation of the inflammatory response may have some deleterious consequences in host cells. In this respect, the potential use of natural antioxidants is worth considering, including melatonin and some vitamins, as possible novel anti-Toxoplasma therapeutics. Results of in vitro and animal studies are promising. However, supplementation with some antioxidants was found to promote the increase in parasitemia, and the disease was then characterized by a milder course. Undoubtedly, research in this area may have a significant impact on the future prospects of toxoplasmosis therapy.

scholarly journals A Comparative Genomic Study of Attenuated and Virulent Strains of Babesia bigemina

Pathogens ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 318
Author(s):  
Bernardo Sachman-Ruiz ◽  
Luis Lozano ◽  
José J. Lira ◽  
Grecia Martínez ◽  
Carmen Rojas ◽  
...  
Keyword(s):  
In Vitro Culture ◽  
Virulence Genes ◽  
Laboratory Strain ◽  
Host Cells ◽  
Comparative Genomic ◽  
Local Alignment ◽  
Host Immune System ◽  
Babesia Bigemina ◽  
Genomic Study

Cattle babesiosis is a socio-economically important tick-borne disease caused by Apicomplexa protozoa of the genus Babesia that are obligate intraerythrocytic parasites. The pathogenicity of Babesia parasites for cattle is determined by the interaction with the host immune system and the presence of the parasite’s virulence genes. A Babesia bigemina strain that has been maintained under a microaerophilic stationary phase in in vitro culture conditions for several years in the laboratory lost virulence for the bovine host and the capacity for being transmitted by the tick vector. In this study, we compared the virulome of the in vitro culture attenuated Babesia bigemina strain (S) and the virulent tick transmitted parental Mexican B. bigemina strain (M). Preliminary results obtained by using the Basic Local Alignment Search Tool (BLAST) showed that out of 27 virulence genes described and analyzed in the B. bigemina virulent tick transmitted strain, only five were fully identified in the attenuated laboratory strain. In all cases, the identity and coverture of the identified genes of the wildtype strain were higher than those of the laboratory strain. This finding is putatively associated with the continuous partial loss of virulence genes in the laboratory strain after several passages of the parasite population under optimal in vitro growth conditions. The loss of virulence factors might be reflected in the absence of symptoms of the disease in cattle inoculated with the attenuated strain despite the presence of infection in the bovine host cells.

Survival of Lactobacillus delbrueckii UFV H2b20 in fermented milk under simulated gastric and intestinal conditions

2013 ◽  
Vol 4 (3) ◽  
pp. 285-289 ◽  
Author(s):  
L.L. da Conceição ◽  
E.S. Leandro ◽  
F.S. Freitas ◽  
M.N.V. de Oliveira ◽  
A.B. Ferreira-Machado ◽  
...  
Keyword(s):  
Gastrointestinal Tract ◽  
Storage Period ◽  
Fermented Milk ◽  
Storage Conditions ◽  
Lactobacillus Delbrueckii ◽  
Refrigerated Storage ◽  
Human Gastrointestinal Tract ◽  
Log Reduction ◽  
Population Reduction ◽  
Potential Use

The survival of Lactobacillus delbrueckii UFV H2b20 was assessed in fermented milk, both during the storage period and after exposure to simulated gastric and intestinal juices, as well the detection of the gene fbpA involved in adherence to human gastrointestinal tract. L. delbrueckii UFV H2b20 remained stable and viable for 28 days under refrigerated storage conditions. After one day of storage, that strain exhibited a one-log population reduction following exposure in tandem to simulated gastric and intestinal juices. After 14 days of storage, a two-log reduction was observed following 90 min of exposure to the simulated gastric conditions. However, the strain did not survive following exposure to the simulated intestinal juice. The observed tolerance to storage conditions and resistance to the simulated gastric and intestinal conditions confirm the potential use of L. delbrueckii UFV H2b20 as a probiotic, which is further reinforced by the detection of fbpA in this strain.

Chromogranin: A newly recognized marker for endocrine cells of the human gastrointestinal tract

1985 ◽  
Vol 89 (6) ◽  
pp. 1366-1373 ◽  
Author(s):  
P. Facer ◽  
A.E. Bishop ◽  
R.V. Lloyd ◽  
B.S. Wilson ◽  
R.J. Hennessy ◽  
...  
Keyword(s):  
Gastrointestinal Tract ◽  
Chromogranin A ◽  
Endocrine Cells ◽  
Human Gastrointestinal Tract

In vitro Gastrointestinal Models for Prebiotic Carbohydrates: A Critical Review

2019 ◽  
Vol 25 (32) ◽  
pp. 3478-3483 ◽  
Author(s):  
Oswaldo Hernandez-Hernandez
Keyword(s):  
Small Intestine ◽  
Gastrointestinal Tract ◽  
Brush Border ◽  
Critical Review ◽  
In Vitro Digestibility ◽  
Human Gastrointestinal Tract ◽  
Intestinal Brush Border ◽  
Small Intestinal ◽  
Existing Data

Background: In the last decade, various consortia and companies have created standardized digestion protocols and gastrointestinal simulators, such as the protocol proposed by the INFOGEST Consortium, the simulator SHIME, the simulator simgi®, the TIM, etc. Most of them claim to simulate the entire human gastrointestinal tract. However, few results have been reported on the use of these systems with potential prebiotic carbohydrates. Methods: This critical review addresses the existing data on the analysis of prebiotic carbohydrates by different in vitro gastrointestinal simulators, the lack of parameters that could affect the results, and recommendations for their enhancement. Results: According to the reviewed data, there is a lack of a realistic approximation of the small intestinal conditions, mainly because of the absence of hydrolytic conditions, such as the presence of small intestinal brush border carbohydrases that can affect the digestibility of different carbohydrates, including prebiotics. Conclusion: There is a necessity to standardize and enhance the small intestine simulators to study the in vitro digestibility of carbohydrates.

scholarly journals Multiparameter Optimization of Trypanocidal Cruzain Inhibitors With In Vivo Activity and Favorable Pharmacokinetics

2022 ◽  
Vol 12 ◽  
Author(s):  
Ivani Pauli ◽  
Celso de O. Rezende Jr. ◽  
Brian W. Slafer ◽  
Marco A. Dessoy ◽  
Mariana L. de Souza ◽  
...  
Keyword(s):  
Parasite Burden ◽  
Host Cells ◽  
Benzimidazole Derivatives ◽  
Pharmacokinetic Studies ◽  
Host Immune System ◽  
Novel Drugs ◽  
Main Metabolic Pathway ◽  
Multiparameter Optimization

Cruzain, the main cysteine protease of Trypanosoma cruzi, plays key roles in all stages of the parasite’s life cycle, including nutrition acquisition, differentiation, evasion of the host immune system, and invasion of host cells. Thus, inhibition of this validated target may lead to the development of novel drugs for the treatment of Chagas disease. In this study, a multiparameter optimization (MPO) approach, molecular modeling, and structure-activity relationships (SARs) were employed for the identification of new benzimidazole derivatives as potent competitive inhibitors of cruzain with trypanocidal activity and suitable pharmacokinetics. Extensive pharmacokinetic studies enabled the identification of metabolically stable and permeable compounds with high selectivity indices. CYP3A4 was found to be involved in the main metabolic pathway, and the identification of metabolic soft spots provided insights into molecular optimization. Compound 28, which showed a promising trade-off between pharmacodynamics and pharmacokinetics, caused no acute toxicity and reduced parasite burden both in vitro and in vivo.

scholarly journals Microplastics as Vectors of Chromium and Lead during Dynamic Simulation of the Human Gastrointestinal Tract

2020 ◽  
Vol 12 (11) ◽  
pp. 4792
Author(s):  
Verónica Godoy ◽  
Antonio Martínez-Férez ◽  
María Ángeles Martín-Lara ◽  
José Antonio Vellido-Pérez ◽  
Mónica Calero ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Gastrointestinal Tract ◽  
Human Body ◽  
Surface Porosity ◽  
Human Gastrointestinal Tract ◽  
Future Studies ◽  
Other Substances ◽  
First Time ◽  
Kinetics Of

The human body is exposed to the ingestion of microplastics that are often contaminated with other substances, which can be released into our body. In this work, a dynamic in-vitro simulator of the gastrointestinal tract based on a membrane reactor has been used for the first time to study the release, bioaccessibility, and bioavailability of chromium (Cr) and lead (Pb) from polyethylene and polypropylene microplastics previously contaminated in the laboratory. The results showed that 23.11% of the initial Cr and 23.17% of the initial Pb present in microplastics were able to cross the tubular membrane, simulating the intestinal absorption phase. The pH evolution during the gastric phase and the duodenal phase, the interaction mechanisms with physiological fluids, and the properties of the polymers, such as specific surface, porosity, and/or surface degradation, affected the kinetics of release from the microplastics and the behavior of both heavy metals. Cr was released very early in the gastric phase, but also began simultaneously to precipitate quite fast, while Pb was released slower and in less quantity than Cr, and did not precipitate until the beginning of the duodenal phase. This study shows, for the first time, how useful the dynamic gastrointestinal simulator is to study the behavior of microplastics and some problematic heavy metals along the human gastrointestinal tract, and can serve as a reference for future studies focused on the effects of these substances in the human body.

scholarly journals Motor responses of human gastrointestinal tract to 5-hydroxytryptamine in vivo and in vitro

Gut ◽  
1966 ◽  
Vol 7 (3) ◽  
pp. 208-216 ◽  
Author(s):  
J. J. Misiewicz ◽  
S. L. Waller ◽  
M. Eisner
Keyword(s):  
Gastrointestinal Tract ◽  
Human Gastrointestinal Tract ◽  
Motor Responses
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