Gut Microbiota and Nutritional Science Quiz

Prebiotics, Probiotics, and Gut Microbiome Modulation

• Prebiotics are non-digestible food components that selectively nourish beneficial gut microorganisms.
• Probiotics are live microorganisms that when administered in sufficient amounts confer a health benefit on the host.
• Prebiotics are used to restore/establish a balanced gut microflora.
• Probiotics are used to restore/establish a balanced gut microflora.

Modulation of the Gut Microbiome

• There is no single "magic bullet" diet for a healthy gut microbiome.
• Dietary approaches and therapeutic interventions can modify the gut microbiome.
• Various therapeutic strategies can be used to modulate the gut microbiota, including:
  • Prebiotics
  • Probiotics
  • Synbiotics
  • FMT (fecal microbiota transplantation)
  • Phage therapy
  • miRNA therapies

Probiotic Criteria

• Probiotics must meet specific criteria for safety and functionality:
  • Human or animal origin, isolated from healthy individuals
  • Established history of safe use
  • Precise diagnostic identification (phenotype and genotype)
  • Lack of association with infective disease or bile acid salt cleavage
  • Absence of adverse effects
  • Competitiveness with the existing gut microorganisms
  • Resistance to bile, stomach acid, and enzymes
  • Ability to colonize and thrive in the target location in the gut
  • Antagonistic activity toward pathogens
  • Adherence to gut tissue

Probiotics and Specific Diseases

• Inflammatory bowel disease (IBD): Probiotics can sometimes help with ulcerative colitis but have no significant effect on Crohn's disease.
• Lactose intolerance: Probiotics can help increase lactose digestion and tolerance but should be carefully selected or used in conjunction with diet modification.
• Irritable bowel syndrome (IBS): Probiotics can lead to significant improvement in IBS symptoms (bloating, abdominal pain, constipation, abdominal cramps, and flatulence).
• Cancer: Animal studies suggest probiotics may reduce colorectal carcinoma risk but this is not confirmed in clinical trials. Probiotics can help alleviate gastrointestinal disorders in patients with cancer, by improving gut mucosal barrier integrity and reducing incidences of diarrhoea and discomfort.
• Diarrhoea & Intestinal Infections: Probiotics like Saccharomyces boulardii have shown efficacy in treating acute watery diarrhoea. They can also help in non-nosocomial, nosocomial and viral diarrhoeas. Probiotics increase the amount of IgA antibodies and arrest viral infection. Probiotics can reduce the incidence of Antibiotic-associated diarrhoea (AAD) and Clostridium difficile disease (CDD).
• Extraintestinal Infections: Studies have shown that probiotics reduce vaginitis, respiratory tract infections, and nosocomial infections (e.g., VAP) in cystic fibrosis patients.
• Metabolic Disorders: Probiotic administration can lead to reductions in BMI, arterial BP, CRP levels, and improved lipid profiles and insulin sensitivity in obesity patients. It also reduces blood glucose, HbA1c, LDL, and total cholesterol in T2D patients.
• Atopic Dermatitis (Eczema): Probiotic consumption in pregnant women and their infants can reduce the cumulative prevalence of eczema.

Prebiotics

• Prebiotics are non-digestible food ingredients that selectively stimulate the growth and/or activity of beneficial colonic microorganisms.
• The majority of prebiotics are carbohydrates, such as fructooligosaccharides (FOS), galactooligosaccharides (GOS), inulin, xylooligosaccharides (XOS), lactitol, lactosucrose, and lactulose naturally occurring in human and animal diets.

Synbiotics

• Synbiotics are a combination of prebiotics and probiotics.
• The purpose is to improve the survival of probiotics in the gut, and stimulate the growth of specific beneficial gut bacteria.
• Prebiotics in combination with probiotics can enhance the tolerance of probiotics to gut environment factors such as pH, temperature and oxygen.
• Synbiotics have shown to have beneficial effects on humans concerning:
  • Increased Lactobacillus and Bifidobacterium
  • Improved hepatic function in patients with cirrhosis
  • Improved immunomodulation
  • Reduced nosocomial infections in post-surgery.

Gut Microbiota Metabolites

• Gut microbiota-associated metabolites are crucial in regulating human diseases and are now being explored as therapeutic agents.
• Metabolites are used in the treatment of:
  • Local inflammation
  • Cardiometabolic disorders
  • Neurological disorders
  • Cancers
  • These metabolites have desirable characteristics, such as: bioavailability, high concentration, ease of administration, and tissue tolerability.
• Short-chain fatty acids (SCFAs), such as butyrate, exhibit anti-inflammatory activity and can alleviate symptoms of conditions like encephalitis and multiple sclerosis.

Other Novel Approaches

• miRNAs: these regulate gene expression at the cellular level.
• Hyaluronan: promotes and resolves IBD.
• Nanomaterials: can reshape cancer causing dysbiotic microorganisms and metabolites found in the cancer microenvironment.

Test your knowledge on the role of short-chain fatty acids (SCFAs) such as butyric acid in gene regulation and their effects on human health. This quiz also covers synbiotics, prebiotics, and the benefits associated with probiotics. Dive deep into the science of gut microbiota modulation and its implications for nutrition.