Identification of Suitable Reference Genes for Quantitative Gene Expression Analysis in Innervated and Denervated Adipose Tissue from Cafeteria Diet-Fed Rats

Juvenile cannabidiol chronic treatments produce robust changes in metabolic markers in adult male Wistar rats

The use of cannabidiol (CBD), the non-psychotropic compound derived from Cannabis sativa, for therapeutic purposes is growing exponentially by targeting the management of multiple medical disorders, including metabolic-related diseases. Nevertheless, substantial questions have emerged in concerning the potential metabolic disturbances in adulthood as consequence of the long-term uses of CBD during early years of life. Therefore, we studied whether chronic CBD injections (5, 10 or 30 mg/kg; i.p.) given to juvenile rats (from post-natal day [PND] 30) for 14 days might influence in adulthood the activity of metabolic markers, such as glucose, total cholesterol, triglycerides as well as activity of antioxidants (DPPH) from plasma, white adipose tissue (WAT), brown adipose tissue (BAT), liver, and hypothalamus. Our results showed that adult rats treated during juvenile ages with CBD (5, 10 or 30 mg/kg) for two weeks increased the contents of glucose whereas with no changes on total cholesterol in adulthood were observed. Additionally, a significant decrease in the levels of triglycerides were found in plasma, WAT, BAT, and liver in adult rats treated with chronic injections of CBD during the adolescence. However, unexpectedly, the contents of triglycerides in hypothalamus were found enhanced. Finally, the DPPH assay showed a significant enhancement in triglycerides analyzed from WAT and liver whereas opposite findings were observed in BAT and no significant changes were found in hypothalamus in adult rats that received during the adolescence chronic injections of CBD. In conclusion, repeated CBD administration to juvenile rats induced significant alterations in multiple metabolic markers analyzed in the adulthood. Our findings highlight the relevance of chronic CBD treatment in disturbed metabolic activity and remark the need for studying the underlying mechanisms involved.

Determination of novel reference genes for improving gene expression data normalization in selected canine reproductive tissues - a multistudy analysis

Background

Real time RT-PCR (qPCR) is a useful and powerful tool for quantitative measurement of gene expression. The proper choice of internal standards such as reference genes is crucial for correct data evaluation. In female dogs, as in other species, the reproductive tract is continuously undergoing hormonal and cycle stage-dependent morphological changes, which are associated with altered gene expression. However, there have been few attempts published so far targeted to the dog aimed at determining optimal reference genes for the reproductive organs. Most of these approaches relied on genes previously described in other species. Large-scale transcriptome-based experiments are promising tools for defining potential candidate reference genes, but were never considered in this context in canine research.

Results

Here, using available microarray and RNA-seq datasets derived from reproductive organs (corpus luteum, placenta, healthy and diseased uteri) of dogs, we have performed multistudy analysis to identify the most stably expressed genes for expression studies, in each tissue separately and collectively for different tissues. The stability of newly identified reference genes (EIF4H, KDELR2, KDM4A and PTK2) has been determined and ranked relative to previously used reference genes, i.e., GAPDH, β-actin and cyclophillin A/PPIA, using RefFinder and NormFinder algorithms. Finally, expression of selected target genes (luteal IL-1b and MHCII, placental COX2 and VEGFA, and uterine IGF2 and LHR) was re-evaluated and normalized. All proposed candidate reference genes were more stable, ranked higher and introduced less variation than previously used genes.

Conclusions

Based on our analyses, we recommend applying KDM4A and PTK2 for normalization of gene expression in the canine CL and placenta. The inclusion of a third reference gene, EIF4H, is suggested for healthy uteri. With this, the interpretation of qPCR data will be more reliable, allowing better understanding of canine reproductive physiology.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-020-02635-6.

Cardiac sympathetic drive is increased in cafeteria diet-fed rats independent of impairment in peripheral baroreflex and chemoreflex functions

BACKGROUND AND AIMS

Consumption of a high caloric diet induces autonomic imbalance, which can lead to cardiovascular disease. Impaired arterial baroreflex control is suggested to play an important role in cardiovascular autonomic imbalance, often seen in obesity. We previously demonstrated that cafeteria diets increase the sympathetic drive to white and brown adipose tissue.

METHODS AND RESULTS

After feeding a cafeteria diet to rats for 26 days, we evaluated: (i)heart rate (HR) and arterial pressure (AP); (ii)baroreflex and chemoreflex function; and (iii) autonomic modulation of the heart and vessels, measured through pulse interval (PI) and systolic arterial pressure (SAP) variability analyses and following administration of autonomic blockers. The cafeteria diet increased body fat mass and serum insulin, leptin, triacylglycerol and cholesterol levels. Baseline HR (15%) was also increased, accompanied by increased power in the low frequency band (60%) and in the low frequency/high frequency ratio (104%) in the PI spectra. Nonlinear analysis revealed an increased occurrence of 0V (39%) and decreased occurrence of 2UV (18%) patterns. Following administration of autonomic blockers, we observed an increase in cardiac sympathetic tone (425%) in cafeteria diet-fed rats. The cafeteria diet had no effect on AP, SAP variability, baroreflex and chemoreflex control.

CONCLUSION

Our findings suggest that consumption of a cafeteria diet increases sympathetic drive to the heart but not to the blood vessels, independent of impairment in baroreflex and chemoreflex functions. Other mechanisms may be involved in the increased cardiac sympathetic drive, and compensatory vascular mechanisms may prevent the development of hypertension in this model of obesity.

Reduction of IL-6 gene expression in human adipose tissue after sleeve gastrectomy surgery

OBJECTIVE

There is increasing evidence that immune cell interactions in adipose tissue contribute to the development of metabolic dysfunction. Pro-inflammatory cytokines have been shown to mediate insulin resistance, and the presence of macrophages is a salient feature in the development of obesity. The present study aimed to evaluate adipocyte size and macrophage activation in women before and 3 months after laparoscopic vertical sleeve gastrectomy (VSG).

METHODS

Subcutaneous abdominal adipose tissue biopsies were obtained from women scheduled to undergo VSG. Histological evaluation of adipocytes and macrophages was performed as well as cytokine expression quantification before and after VSG-induced weight loss.

RESULTS

Weight loss following VSG resulted in a reduction in adipocyte size as well as a decrease in interleukin (IL)-6 cytokine mRNA expression in subcutaneous adipose tissue. There was no change in the presence of crownlike structures after weight loss.

CONCLUSIONS

Early weight loss after VSG is associated with a reduction in adipocyte size and a decline in IL-6 gene expression in local adipose tissue. Macrophage infiltration and crownlike density structures persist in adipose tissue from tissues impacted by excess body weight 3 months after VSG-induced weight loss.