Pasteurized Akkermansia muciniphila protects from fat mass gain but not from bone loss

Abstract

Probiotic bacteria can protect from ovariectomy (ovx)-induced bone loss in mice. Akkermansia muciniphila is considered to have probiotic potential due to its beneficial effect on obesity and insulin resistance. The purpose of the present study was to determine if treatment with pasteurized Akkermansia muciniphila (p Akk) could prevent ovx-induced bone loss. Mice were treated with vehicle or p Akk for 4 wk, starting 3 days before ovx or sham surgery. Treatment with p Akk reduced fat mass accumulation confirming earlier findings. However, treatment with p Akk decreased trabecular and cortical bone mass in femur and vertebra of gonadal intact mice and did not protect from ovx-induced bone loss. Treatment with p Akk increased serum parathyroid hormone (PTH) levels and increased expression of the calcium transporter Trpv5 in kidney suggesting increased reabsorption of calcium in the kidneys. Serum amyloid A 3 (SAA3) can suppress bone formation and mediate the effects of PTH on bone resorption and bone loss in mice and treatment with p Akk increased serum levels of SAA3 and gene expression of Saa3 in colon. Moreover, regulatory T cells can be protective of bone and p Akk-treated mice had decreased number of regulatory T cells in mesenteric lymph nodes and bone marrow. In conclusion, treatment with p Akk protected from ovx-induced fat mass gain but not from bone loss and reduced bone mass in gonadal intact mice. Our findings with p Akk differ from some probiotics that have been shown to protect bone mass, demonstrating that not all prebiotic and probiotic factors have the same effect on bone.

Extracellular Vesicles from Child Gut Microbiota Enter into Bone to Preserve Bone Mass and Strength

“…As shown in Figure S5A,B in the Supporting Information, pasteurization caused 100% death of Akk and entirely blocked the secretion of EVs by Akk , suggesting that the failure of pasteurized Akk to induce bone‐protective effects in study by Lawenius et al. [ 27 ] may be associated with the impairment of production of Akk ‐EVs.…”

“…The first reason is likely that the process of pasteurization causes Akk death and impairs the production of functional Akk ‐EVs. The negative effect of pasteurized Akk on bone mass in normal mice [ 27 ] may be due to that the death of Akk results in the generation of some substances detrimental to bone, which still needs future investigation. Second, the difference in the frequency of Akk treatment may also lead to two opposite outcomes.…”

Stochasticity constrained by deterministic effects of diet and age drive rumen microbiome assembly dynamics

“…To the best of our knowledge, there is little or no evidence that this species is present the adult cow rumen while the genus Akkermansia has been reported to exist in the gastrointestinal tract of goats and camels 37,38 . A. muciniphila is a mucin degrader and an abundant member of the human gut microbiome [39][40][41][42] . The transition from the first to the second month of life was followed by an increase in members of the Firmicutes phylum, which was mainly attributed to the Lachnospiraceae family ( Fig.…”

The Bacterium Akkermansia muciniphila: A Sentinel for Gut Permeability and Its Relevance to HIV-Related Inflammation

“…In addition, even when A. muciniphila is killed through pasteurization, supplementation demonstrated beneficial effects by protecting from ovariectomy-induced fat mass gain (72). In overweight insulin-resistant humans, a randomized, doubleblind, placebo-controlled pilot study showed that daily oral supplementation of 10 10 live or pasteurized A. muciniphila bacteria for 3 months was safe and well tolerated, and improved insulin sensitivity, reduced insulinemia, plasma total cholesterol, body weight, fat mass and hip circumference, without great changes in the overall gut microbiota composition (43).…”