Resistant starch, microbiome, and precision modulation

Abstract

Resistant starch, microbiome, and precision modulation. Mounting evidence has positioned the gut microbiome as a nexus of health. Modulating its phylogenetic composition and function has become an attractive therapeutic prospect. Resistant starches (granular amylase-resistant αglycans) are available as physicochemically and morphologically distinguishable products. Attempts to leverage resistant starch as microbiome-modifying interventions in clinical studies have yielded remarkable inter-individual variation. Consequently, their utility as a potential therapy likely depends predominantly on the selected resistant starch and the subject's baseline microbiome. The purpose of this review is to detail i) the heterogeneity of resistant starches, ii) how resistant starch is sequentially degraded and fermented by specialized gut microbes, and iii) how resistant starch interventions yield variable effects on the gut microbiome.

Resistant Starches and Non-Communicable Disease: A Focus on Mediterranean Diet

“…Indeed, a study performed on hemodialysis patients, who had taken RS2 for 4 weeks, evidenced a decreased IL-6 concentration [ 80 ]. In agreement, in patients with systemic inflammation associated with chronic kidney disease, a supplemented diet containing high-amylose maize RS2 elicited a significant decrease in serum levels of IL-6 and TNFα with respect to the placebo [ 81 ]. On the contrary, in women with type 2 diabetes, RS2 dietary intake did not induce any significant change in IL-6 concentration compared to the placebo [ 82 ].…”

Resistant starch—An accessible fiber ingredient acceptable to the Western palate

“…Starch granules from tubers are among the most hydrolysis‐resistant native starches (Dobranowski & Stintzi, 2021). The resistance of raw potato starch may result from the large size of its granules, which limit the area availabile to digestive enzymes (Leszczyński, 2004).…”

“…The third classification of RS refers to retrograded starch which may be processed from unmodified starch or result from food processing applications. The retrogradation process occurs when starch undergoes gelatinization, followed by a thermodynamically driven reconfiguration of amylose and amylopectin into a new ordered state (Dobranowski & Stintzi, 2021). Although cooking can initially increase unmodified starch digestibility, subsequent heat treatment can lead to the formation of crystallites resistant to digestion (Topping et al., 2003).…”

“…Accumulating evidence suggests that the gut microbiome is a “nexus of health” (Dobranowski & Stintzi, 2021), and the alteration of its phylogenetic composition and function may offer a safe therapeutic therapy. Typically, Westernized diets are low in fermentable dietary fibers such as RS.…”

“…It is reported that such low intakes may reduce bacterial diversity, lead to thinner mucus layers, compromise intestinal epithelial integrity, and increase pathogen susceptibility (Gill et al., 2021). The effectiveness of RS as a therapeutic agent may however be highly dependent on the host's baseline microbiome composition and the selected source of RS (Dobranowski & Stintzi, 2021).…”