Pulse wave velocity is associated with increased plasma oxLDL in ageing but not with FGF21 and habitual exercise

Fibroblast growth factor 21 (FGF21) and adiponectin increase expression of genes involved in antioxidant pathways, but their roles in mediating oxidative stress and arterial stiffness with ageing and habitual exercise remain unknown. We explored the role of the FGF21–adiponectin axis in mediating oxidative stress and arterial stiffness with ageing and habitual exercise. Eighty age- and sex-matched healthy individuals were assigned to younger sedentary or active (18–36 years old,n=20 each) and older sedentary or active (45–80 years old,n=20 each) groups. Arterial stiffness was measured indirectly using pulse wave velocity (PWV). Fasted plasma concentrations of FGF21, adiponectin and oxidized low-density lipoprotein (oxLDL) were measured. PWV was 0.2-fold higher and oxLDL concentration was 25.6% higher (both p<0.001) in older than younger adults, despite no difference in FGF21 concentration (p=0.097) between age groups. PWV (p=0.09) and oxLDL concentration (p=0.275) did not differ between activity groups but FGF21 concentration was 9% lower in active than sedentary individuals (p=0.011). Adiponectin concentration did not differ by age (p=0.642) or exercise habits (p=0.821). In conclusion, age, but not habitual exercise, was associated with higher oxidative stress and arterial stiffness. FGF21 and adiponectin did not differ between younger and older adults, unlikely mediating oxidative stress and arterial stiffness in healthy adults. <br

The piPSCs-enriched miRNA cluster promotes the reprogramming of porcine cells.

<p>(A) The DIANA miPath program predict the pathways regulated by the miR-106a-363 cluster. Heatmap of the miR-106a-363 cluster versus other pathways, where the miRNAs are clustered together when they exhibited similar pathway-targeting patterns, and the pathways are clustered together by related miRNAs. (B) The DIANA miPath program predicted the pathways regulated by the miR-302 cluster. (C) The PCR region used to clone the genomic locus of the miR-106a-363 cluster and putative miR-302 cluster. (D) Amplification of the genomic region containing the miR-106a-363 cluster and putative miRNA-302 cluster. An approximately 1.5 kb range harboring the whole miRNA-106a-363 cluster and a 2 kb range containing the putative porcine miR-302 cluster were amplified. The marker indicates the DNA ladder. (E) AP staining of the piPSCs colonies. (F) Statistical analysis of AP positive colonies. Mean values ± SD are shown. ***P-value < 0.001.</p

The results of the GO and KEGG analyses of predicted target genes of the differentially expressed miRNAs.

<p>(A) The results of a GO analysis of the target genes of hpiPSCs-specific miRNAs (B) The results of a GO analysis of the target genes of mpiPSCs-specific miRNAs. (C) The results of a KEGG pathway analysis of the target genes of hpiPSCs-specific miRNAs. (D) The results of a KEGG pathway analysis of the target genes of mpiPSCs-specific miRNAs. (E) The network of putative target genes and hpiPSCs-specific miRNAs interacting in hpiPSCs. (F) The network of putative target genes and mpiPSCs-specific miRNAs interacting in mpiPSCs.</p

Distinct MicroRNA Expression Signatures of Porcine Induced Pluripotent Stem Cells under Mouse and Human ESC Culture Conditions

<div><p>It is well known that microRNAs play a very important role in regulating reprogramming, pluripotency and cell fate decisions. Porcine induced pluripotent stem cells (piPSCs) are now available for studying the pluripotent regulation network in pigs. Two types of piPSCs have been derived from human and mouse embryonic stem cell (ESC) culture conditions: hpiPSCs and mpiPSCs, respectively. The hpiPSCs were morphologically similar to human ESCs, and the mpiPSCs resembled mouse ESCs. However, our current understanding of the role of microRNAs in the development of piPSCs is still very limited. Here, we performed small RNA sequencing to profile the miRNA expression in porcine fibroblasts (pEFs), hpiPSCs and mpiPSCs. There were 22 differential expressed (DE) miRNAs down-regulated in both types of piPSCs compared with pEFs, such as ssc-miR-145-5p and ssc-miR-98. There were 27 DE miRNAs up-regulated in both types of piPSCs compared with pEFs. Among these up-regulated DE miRNAs in piPSCs, ssc-miR-217, ssc-miR-216, ssc-miR-142-5p, ssc-miR-182, ssc-miR-183 and ssc-miR-96-5p have much higher expression levels in mpiPSCs, while ssc-miR-106a, ssc-miR-363, ssc-miR-146b, ssc-miR-195, ssc-miR-497, ssc-miR-935 and ssc-miR-20b highly expressed in hpiPSCs. Quantitative stem-loop RT-PCR was performed to confirm selected DE miRNAs expression levels. The results were consistent with small RNA sequencing. Different expression patterns were observed for key miRNA clusters, such as the miR-17-92 cluster, the let-7 family, the miR-106a-363 cluster and the miR-182-183 cluster, in the mpiPSCs and hpiPSCs. Novel miRNAs were also predicted in this study, including a putative porcine miR-302 cluster: ssc_38503, ssc_38503 and ssc_38501 (which resemble human miR-302a and miR-302b) found in both types of piPSCs. The miR-106a-363 cluster and putative miR-302 cluster increased the reprogramming efficiency of pEFs. The study revealed significant differences in the miRNA signatures of hpiPSCs and mpiPSCs under different pluripotent states that were derived from different culture conditions. These differentially expressed miRNAs may play important roles in pluripotent regulation in pigs, and this information will facilitate the understanding of the mechanism of pluripotency in pigs.</p></div

Differential expressed miRNAs up-regulated in both two types of piPSCs compared with pEFs (|log₂(FC)|≥1, total counts >10, P-value < 0.05).

<p>Differential expressed miRNAs up-regulated in both two types of piPSCs compared with pEFs (|log₂(FC)|≥1, total counts >10, P-value < 0.05).</p

The distribution of small RNA reads and various RNA classes in piPSCs and pEFs.

<p>(A) The morphological features and AP staining of piPSCs. Scale bar = 500 μm. (B) The distribution of small RNA reads in the piPSCs and pEFs. (C) Pie chart showing the various RNA classes in pEFs and piPSCs.</p

The specific DE miRNAs of hpiPSCs and mpiPSCs.

<p>(A) Volcano plot of hpiPSCs versus mpiPSCs. Red plots indicate DE miRNAs up-regulated in hpiPSCs. Green plots indicated DE miRNAs down-regulated in hpiPSCs. DE miRNAs were selected by |log₂(FC)|≥1, P-value <0.05. (B) Relative expression of selected hpiPSCs-specific miRNAs. (C) Relative expression of selected mpiPSCs-specific miRNAs.</p

Differentially expressed miRNAs specifically up-regulated in mpiPSCs versus pEFs (|log₂(FC)|≥1, total counts >10, P-value < 0.05).

<p>Differentially expressed miRNAs specifically up-regulated in mpiPSCs versus pEFs (|log₂(FC)|≥1, total counts >10, P-value < 0.05).</p

Representative miRNAs and miRNA clusters of pEFs, hpiPSCs and mpiPSCs.

<p>Representative miRNAs and miRNA clusters of pEFs, hpiPSCs and mpiPSCs.</p

Novel porcine miRNAs predicted by miRdeep2.

<p>(A) Heatmap of the differentially expressed novel miRNAs. (B) Venn diagram of the differentially expressed novel miRNAs. (C) BLAST results for ssc_38501, ssc_38503 and ssc_38508 with has-miR-302a/b and mmu-miR-302a/b. (D) Secondary structures of the ssc_38501, ssc_38503 and ssc_38508 pre-miRNAs. (E) Scatter plot of the miRNA expression of piPSCs compared with pEFs. The up-regulated miRNAs are shown as red spots while the down-regulated miRNAs are shown as green spots. The ssc_38501, ssc_38503 and ssc_38508 are shown as black spots.</p