Conserved properties of genetic architecture of renal and fat transcriptomes in rat models of insulin resistance

The regulatory landscape of multiple brain regions in outbred heterogeneous stock rats

Heterogeneous Stock (HS) rats are a genetically diverse outbred rat population that is widely used for studying genetics of behavioral and physiological traits. Mapping Quantitative Trait Loci (QTL) associated with transcriptional changes would help to identify mechanisms underlying these traits. We generated genotype and transcriptome data for five brain regions from 88 HS rats. We identified 21 392 cis-QTLs associated with expression and splicing changes across all five brain regions and validated their effects using allele specific expression data. We identified 80 cases where eQTLs were colocalized with genome-wide association study (GWAS) results from nine physiological traits. Comparing our dataset to human data from the Genotype-Tissue Expression (GTEx) project, we found that the HS rat data yields twice as many significant eQTLs as a similarly sized human dataset. We also identified a modest but highly significant correlation between genetic regulatory variation among orthologous genes. Surprisingly, we found less genetic variation in gene regulation in HS rats relative to humans, though we still found eQTLs for the orthologs of many human genes for which eQTLs had not been found. These data are available from the RatGTEx data portal (RatGTEx.org) and will enable new discoveries of the genetic influences of complex traits.

High-intensity interval training attenuates the effects caused by arterial hypertension in the ventral prostate

BACKGROUND

The prostatic effects induced by arterial hypertension is very controversial and its mechanism is unclear. High-intensity interval training (HIIT) is an exercise considered to be hypotensive. The objective of this work was to investigate the molecular, biochemical, and morphological effects of 8 weeks of HIIT in the prostatic tissue of spontaneously hypertensive rats (SHR).

METHODS

Twenty male SHR rats, 51.4 weeks old, were used. The SHR animals were divided into two groups: spontaneously sedentary hypertensive and spontaneously hypertensive submitted to HIIT. We analyze androgens receptor and glucocorticoid receptors in the prostate. Still, we verify effects of the hypertension and HIIT on the physiopathology prostatic, for immunohistochemistry investigated BCL-2, BAX, IGF-1, FAS/CD95, data's inflammatory tumour necrosis factor α, nuclear factor kappa B and interleukin (IL)-6, anti-inflammatory IL-10. The echocardiographic evaluation was performed at the baseline and after the training period.

RESULTS

Arterial hypertension promote high prostatic intraepithelial neoplasia incidence in the prostate, increases IGF-1, BCL-2 (p < 0.05), and inflammatory proteins (p < 0.05). Eight weeks of HIIT training reduced the arterial pressure and increase the concentration of tissue collagen and intracellular glycogen and showed a higher expression of BAX, FAS/CD95, and IL-10 proteins (p < 0.05), coinciding with a lower incidence of lesions and lower prostate weight (p < 0.05) and reduction of the BCL-2 and IGF-1.

CONCLUSION

Our data suggested that arterial hypertension suppressed apoptosis and increased damage prostatic. On other hand, HIIT promotes morphology and function improves in the prostatic environment, inhibited inflammation, and increased apoptosis.

What lies beyond 100 years of insulin

It has been 100 years since the discovery of insulin. This revolutionary treatment saves the lives of millions of people living with diabetes, but much remains to be understood of its mechanisms and roles in homeostasis and disease. To celebrate this centenary, we explore areas of ongoing insulin research in diabetes, metabolic syndrome and beyond. Disease Models & Mechanisms aims to publish high-quality basic and pre-clinical research that advances our understanding of these conditions to facilitate clinical and public health impact.

Dominant gut Prevotella copri in gastrectomised non-obese diabetic Goto-Kakizaki rats improves glucose homeostasis through enhanced FXR signalling

AIMS/HYPOTHESIS

Drug and surgical-based therapies in type 2 diabetes are associated with altered gut microbiota architecture. Here we investigated the role of the gut microbiome in improved glucose homeostasis following bariatric surgery.

METHODS

We carried out gut microbiome analyses in gastrectomised (by vertical sleeve gastrectomy [VSG]) rats of the Goto-Kakizaki (GK) non-obese model of spontaneously occurring type 2 diabetes, followed by physiological studies in the GK rat.

RESULTS

VSG in the GK rat led to permanent improvement of glucose tolerance associated with minor changes in the gut microbiome, mostly characterised by significant enrichment of caecal Prevotella copri. Gut microbiota enrichment with P. copri in GK rats through permissive antibiotic treatment, inoculation of gut microbiota isolated from gastrectomised GK rats, and direct inoculation of P. copri, resulted in significant improvement of glucose tolerance, independent of changes in body weight. Plasma bile acids were increased in GK rats following inoculation with P. copri and P. copri-enriched microbiota from VSG-treated rats; the inoculated GK rats then showed increased liver glycogen and upregulated expression of Fxr (also known as Nr1h4), Srebf1c, Chrebp (also known as Mlxipl) and Il10 and downregulated expression of Cyp7a1.

CONCLUSIONS

Our data underline the impact of intestinal P. copri on improved glucose homeostasis through enhanced bile acid metabolism and farnesoid X receptor (FXR) signalling, which may represent a promising opportunity for novel type 2 diabetes therapeutics.

lncRNA-mRNA competing endogenous RNA network in IR-hepG2 cells ameliorated by APBBR decreasing ROS levels: a systematic analysis

Background

Radix Astragali (Astragalus membranaceus var. mongholicus (Bunge)) and Coptis chinensis (Coptis chinensis var. angustiloba) are two commonly prescribed traditional Chinese herbs for diabetes. Astragalus Polysaccharide (AP) and Berberine (BBR) are active ingredients of these two herbs respectively and they are scientifically proved to have immunomodulatory and anti-inflammatory effects. They are also known for their antidiabetic potential by ameliorating insulin resistance (IR). AP and BBR have shown different advantages in treating diabetes according to previous reports. However, very few studies focus on the combined activities of the two potential antidiabetic ingredients. In this study, we discovered that reactive oxygen species (ROS) accumulated in IR-hepG2 cells and APBBR can decrease ROS level in model group significantly. We conjectured that APBBR can ameliorate IR in hepG2 cells by decreasing ROS level. In order to verify this hypothesis, we obtained phenotype and transcriptome information of IR-HepG2 cells and explore the underlying mechanism of the combination of AP and BBR(APBBR) activity on the relationship between ROS change in IR at whole-transcriptome level, so as to shed new light to efficacy and application of APBBR in treating diabetes.

Methods

The IR cell model was established with high-level insulin intervention. Glucose content, HepG2 cell viability as well as ROS level was detected to study the effect of IR-hepG2 cell phenotype. Unbiased genome-wide RNA sequencing was used to investigate alterations in experimental groups. Then, GO and KEGG functional enrichment was performed to explore the function and pathway of target genes. Venn analysis found out the differentially expressed lncRNAs that had close relationship with IR and ROS. Finally, we screened out candidate lncRNAs and these target genes to construct interaction network of differentiated lncRNA–miRNA–mRNA by according to the principle of competitive endogenous RNA (ceRNA).

Results

The biochemical experiments showed that APBBR administration could improve the proliferation activity of IR-HepG2 cells and decrease ROS level in model cells. The GO and KEGG functional enrichment analyses demonstrated several mRNAs remarkably enriched in biological processes and signaling pathways related to ROS production and IR progression. Interaction network suggest that APBBR ameliorates IR in HepG2 cells by regulating the expression of multiple genes and activating relevant signaling pathway to decrease ROS level. Thus, we demonstrated that APBBR ameliorated IR in hepG2 cells via the ROS-dependent pathway.