Resistance exercise protects mice from protein-induced fat accretion.

Low-protein (LP) diets extend the lifespan of diverse species and are associated with improved metabolic health in both rodents and humans. Paradoxically, many athletes and bodybuilders consume high-protein (HP) diets and protein supplements, yet are both fit and metabolically healthy. Here, we examine this paradox using weight pulling, a validated progressive resistance exercise training regimen, in mice fed either an LP diet or an isocaloric HP diet. We find that despite having lower food consumption than the LP group, HP-fed mice gain significantly more fat mass than LP-fed mice when not exercising, while weight pulling protected HP-fed mice from this excess fat accretion. The HP diet augmented exercise-induced hypertrophy of the forearm flexor complex, and weight pulling ability increased more rapidly in the exercised HP-fed mice. Surprisingly, exercise did not protect from HP-induced changes in glycemic control. Our results confirm that HP diets can augment muscle hypertrophy and accelerate strength gain induced by resistance exercise without negative effects on fat mass, and also demonstrate that LP diets may be advantageous in the sedentary. Our results highlight the need to consider both dietary composition and activity, not simply calories, when taking a precision nutrition approach to health.

Brief communication: A re-evaluation of the health index of southern Brazilian shellmound populations.

OBJECTIVES: The southern Brazilian shellmounds provide archaeological evidence of prolonged human activity in the coast from approximately 6000 to 1000 BP. Shellmound building populations exploited the rich coastal estuarine zones, and the human remains recovered from them are important sources of information on health and overall lifestyle of these mid-Holocene groups. Therefore, they were included in the Western Hemisphere Global History of Health project. The shellmounds contribute the highest Health Index in the Western Hemisphere, but these conclusions are based on collections that exclude postcranial remains. Here, we reconstruct the Health Index for one specific shellmound using both cranial and postcranial remains to determine whether the initial studies might misrepresent the relative health of the Brazilian shellmound builders. MATERIALS AND METHODS: The Health Index was calculated for a sample of 18 complete skeletons recovered from the shellmound Porto do Rio Vermelho 02 (Santa Catarina Island, Brazil). The Heath Index was calculated with and without postcranial markers and the results are compared with the Western Hemisphere Global History of Health data. RESULTS: The Health Index for Porto do Rio Vermelho 02 is lower than the reported average for American series in the Western Hemisphere Global History of Health Project and considerably lower than the original index reported for Brazilian shellmounds. This discrepancy is due to an increased prevalence of infectious disease and low stature. CONCLUSIONS: Although the Health Index remains a useful comparison statistic, re-evaluation of fragmentary skeletal remains demonstrates the need for caution when applying it to incomplete skeletal series.

Genome-wide miRNA response to anacardic acid in breast cancer cells.

MicroRNAs are biomarkers and potential therapeutic targets for breast cancer. Anacardic acid (AnAc) is a dietary phenolic lipid that inhibits both MCF-7 estrogen receptor α (ERα) positive and MDA-MB-231 triple negative breast cancer (TNBC) cell proliferation with IC50s of 13.5 and 35 µM, respectively. To identify potential mediators of AnAc action in breast cancer, we profiled the genome-wide microRNA transcriptome (microRNAome) in these two cell lines altered by the AnAc 24:1n5 congener. Whole genome expression profiling (RNA-seq) and subsequent network analysis in MetaCore Gene Ontology (GO) algorithm was used to characterize the biological pathways altered by AnAc. In MCF-7 cells, 69 AnAc-responsive miRNAs were identified, e.g., increased let-7a and reduced miR-584. Fewer, i.e., 37 AnAc-responsive miRNAs were identified in MDA-MB-231 cells, e.g., decreased miR-23b and increased miR-1257. Only two miRNAs were increased by AnAc in both cell lines: miR-612 and miR-20b; however, opposite miRNA arm preference was noted: miR-20b-3p and miR-20b-5p were upregulated in MCF-7 and MDA-MB-231, respectively. miR-20b-5p target EFNB2 transcript levels were reduced by AnAc in MDA-MB-231 cells. AnAc reduced miR-378g that targets VIM (vimentin) and VIM mRNA transcript expression was increased in AnAc-treated MCF-7 cells, suggesting a reciprocal relationship. The top three enriched GO terms for AnAc-treated MCF-7 cells were B cell receptor signaling pathway and ribosomal large subunit biogenesis and S-adenosylmethionine metabolic process for AnAc-treated MDA-MB-231 cells. The pathways modulated by these AnAc-regulated miRNAs suggest that key nodal molecules, e.g., Cyclin D1, MYC, c-FOS, PPARγ, and SIN3, are targets of AnAc activity.