Impact of Phyllantus niruri and Lactobacillus amylovorus SGL 14 in a mouse model of dietary hyperoxaluria

Hyperoxaluria is a pathological condition which affects long-term health of kidneys. The present study evaluates the impact of the combination of Lactobacillus amylovorus SGL 14 and the plant extract Phyllantus niruri (namely Phyllantin 14™) on dietary hyperoxaluria. Safety and efficacy of Phyllantin 14 have been evaluated in vivo. Mice C57BL6 fed a high-oxalate diet were compared to mice fed the same diet administered with Phyllantin 14 by gavage for 6 weeks. Control mice were fed a standard diet without oxalate. No adverse effects were associated to Phyllantin 14 supplementation, supporting its safety. Mice fed a high-oxalate diet developed significant hyperoxaluria and those administered with Phyllantin 14 showed a reduced level of urinary oxalate and a lower oxalate-to-creatinine ratio. Soluble and insoluble caecal oxalate were significantly lower in treated group, a finding in agreement with the colonisation study, i.e. mice were colonised with SGL 14 after 3 weeks. Microbiota analysis demonstrated that both oxalate diet and Phyllantin 14 can differently modulate the microbiota. In conclusion, our findings suggest that Phyllantin 14 supplementation represents a potential supportive approach for reducing urinary oxalate and/or for enhancing the efficacy of existing treatments.

Low-protein/high-carbohydrate diet induces AMPK-dependent canonical and non-canonical thermogenesis in subcutaneous adipose tissue

Low-protein/high-carbohydrate (LPHC) diet has been suggested to promote metabolic health and longevity in adult humans and animal models. However, the complex molecular underpinnings of how LPHC diet leads to metabolic benefits remain elusive. Through a multi-layered approach, here we observed that LPHC diet promotes an energy-dissipating response consisting in the parallel recruitment of canonical and non-canonical (muscular) thermogenic systems in subcutaneous white adipose tissue (sWAT). In particular, we measured Ucp1 induction in association with up-regulation of actomyosin components and several Serca (Serca1, Serca2a, Serca2b) ATPases. In beige adipocytes, we observed that AMPK activation is responsible for transducing the amino acid lowering in an enhanced fat catabolism, which sustains both Ucp1-and Serca-dependent energy dissipation. Limiting AMPK activation counteracts the expression of brown fat and muscular genes, including Ucp1 and Serca, as well as mitochondrial oxidative genes. We observed that mitochondrial reactive oxygen species are the upstream molecules controlling AMPK-mediated metabolic rewiring in amino acid-restricted beige adipocytes. Our findings delineate a novel metabolic phenotype of responses to amino acid shortage, which recapitulates some of the benefits of cool temperature in sWAT. In conclusion, this highlights LPHC diet as a valuable and practicable strategy to prevent metabolic diseases through the enhancement of mitochondrial oxidative metabolism and the recruitment of different energy dissipating routes in beige adipocytes.

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LPHC diet promotes brown- and muscular-like features in sWAT.

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In vitro amino acid shortage mimics the effects of LPHC diet.

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AMPK controls canonical and non-canonical thermogenesis in sWAT.

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L-Cys replenishment limits the AMPK-mediated adaptive responses in sWAT.

Probiotic Bifidobacterium lactis, anti-oxidant vitamin E/C and anti-inflammatory dha attenuate lung inflammation due to pm2.5 exposure in mice

The incidence of asthma and allergic diseases of the airways is constantly increasing, both in the industrialised and developing countries, due to harmful and excessive quantities of air pollution. Although some studies have shown an effect of dietary supplementation of specific nutrients (especially with anti-oxidant and anti-inflammatory properties) in reducing airways inflammatory response, the results are not yet conclusive and the science is still at its infancy. Our hypothesis is that combining such nutrients could provide more benefits than using them alone. The aim of the research project proposed here is to investigate whether specific combinations of nutrients (docosahexanoic acid, vitamin C and E, and Bifidobacterium lactis strain BB-12®, included in an engineered diet) can act synergistically to reduce inflammation given by high level of air pollution. Beside the role of docosahexanoic acid, vitamins C and E on airways inflammatory disease, no study examined the effect of the supplementation of this probiotic strain in pathological conditions caused by air pollution so far. Herein we used a well-established in vivo model for the study of pollution effects, which consists in female BALB/c mice receiving by pharyngeal aspiration either a sham or a particulate matter with diameter <2.5 μm (PM 2.5) containing aerosol. Before treatment, mice were fed either a chow or a supplemented diet. By performing histological analyses and gene expression profiles on lung sections and serum measurement of the cytokine interleukin 10, we found that a specific combination of all the aforementioned nutrients rather than nutrients alone had a synergistic protective effect against PM2.5-induced inflammation. In conclusion, our study support that a supplemental nutritional intervention based on a combination of the probiotic B. lactis BB-12, the anti-oxidant vitamin C and E, and the anti-inflammatory docosahexanoic acid represents a rational option for alleviating air pollution-related lung inflammation.

SIRT1 and circadian gene expression in pancreatic ductal adenocarcinoma: Effect of starvation

Pancreatic cancer (PC), the fourth leading cause of cancer-related deaths, is characterized by high aggressiveness and resistance to chemotherapy. Pancreatic carcinogenesis is kept going by derangement of essential cell processes, such as proliferation, apoptosis, metabolism and autophagy, characterized by rhythmic variations with 24-h periodicity driven by the biological clock. We assessed the expression of the circadian genes ARNLT, ARNLT2, CLOCK, PER1, PER2, PER3, CRY1, CRY2 and the starvation-activated histone/protein deacetylase SIRT1 in 34 matched tumor and non-tumor tissue specimens of PC patients, and evaluated in PC derived cell lines if the modulation of SIRT1 expression through starvation could influence the temporal pattern of expression of the circadian genes. We found a significant down-regulation of ARNLT (p = 0.015), CRY1 (p = 0.013), CRY2 (p = 0.001), PER1 (p < 0.0001), PER2 (p < 0.001), PER3 (p = 0.001) and SIRT1 (p = 0.017) in PC specimens. PER3 and CRY2 expression levels were lower in patients with jaundice at diagnosis ( < 0.05). Having adjusted for age, adjuvant therapy and tumor stage, we evidenced that patients with higher PER2 and lower SIRT1 expression levels showed lower mortality (p = 0.028). Levels and temporal patterns of expression of many circadian genes and SIRT1 significantly changed upon serum starvation in vitro, with differences among four different PC cell lines examined (BXPC3, CFPAC, MIA-PaCa-2 and PANC-1). Serum deprivation induced changes of the overall mean level of the wave and amplitude, lengthened or shortened the cycle time and phase-advanced or phase-delayed the rhythmic oscillation depending on the gene and the PC cell line examined. In conclusion, a severe deregulation of expression of SIRT1 and circadian genes was evidenced in the cancer specimens of PC patients, and starvation influenced gene expression in PC cell lines, suggesting that the altered interplay between SIRT1 and the core circadian proteins could represent a crucial player in the process of pancreatic carcinogenesis.