RESUMO
BACKGROUND: Therapies can reduce the risk of heart failure (HF) development and progression in type 2 diabetes; nevertheless, the risk of these outcomes is greater in females than in males. METHODS AND RESULTS: To investigate sex differences in HF development and progression, we compared baseline circulating proteins (Olink Cardiovascular II panel) in males and females with type 2 diabetes and recent acute coronary syndrome for the outcome of HF hospitalization. Data were from the placebo-controlled Examination of Cardiovascular Outcomes with Alogliptin vs Standard of Care (EXAMINE) trial. Pathophysiological sex-differences were interpreted with network and pathway over-representation analyses. The EXAMINE trial enrolled 5380 participants (32.1% females) with biomarker data available for 95.4% of individuals. Analyses revealed 43 biomarkers were differentially expressed in HF hospitalization, of which 18 were sex specific. Among these 43 biomarkers, interleukin-6 was identified as a central node for the pathogenesis of HF hospitalization in both females and in males. Additional pathway over-representation analyses demonstrated that biomarkers associated with inflammatory pathways related to endothelial dysfunction and cardiac fibrosis were more up-regulated in females than males with HF hospitalization. Differential expression of 3 biomarkers (pentraxin-related protein 3, hydroxyacid oxidase 1, and carbonic anhydrase 5A) was independently associated with an increased risk of HF hospitalization in females but not in males (interaction P < .05). CONCLUSIONS: In males and females with type 2 diabetes and acute coronary syndrome, interleukin-6 seems to be central in the pathogenesis of HF. Females exhibit higher levels of circulating proteins related to immunological pathways, reflecting sex-specific differences underlying HF development and progression.
RESUMO
Metabarcoding combines DNA barcoding with high-throughput sequencing, often using one genetic marker to understand complex and taxonomically diverse samples. However, species-level identification depends heavily on the choice of marker and the selected primer pair, often with a trade-off between successful species amplification and taxonomic resolution. We present a versatile metabarcoding protocol for biomonitoring that involves the use of two barcode markers (COI and 18S) and four primer pairs in a single high-throughput sequencing run, via sample multiplexing. We validate the protocol using a series of 24 mock zooplanktonic communities incorporating various levels of genetic variation. With the use of a single marker and single primer pair, the highest species recovery was 77%. With all three COI fragments, we detected 62%-83% of species across the mock communities, while the use of the 18S fragment alone resulted in the detection of 73%-75% of species. The species detection level was significantly improved to 89%-93% when both markers were used. Furthermore, multiplexing did not have a negative impact on the proportion of reads assigned to each species and the total number of species detected was similar to when markers were sequenced alone. Overall, our metabarcoding approach utilizing two barcode markers and multiple primer pairs per barcode improved species detection rates over a single marker/primer pair by 14% to 35%, making it an attractive and relatively cost-effective method for biomonitoring natural zooplankton communities. We strongly recommend combining evolutionary independent markers and, when necessary, multiple primer pairs per marker to increase species detection (i.e., reduce false negatives) in metabarcoding studies.