Gender-dimorphic regulation of liver proteins in Streptozotocin-induced diabetic rats

Tribulus terrestris Efficacy and Safety Concerns in Diabetes and Erectile Dysfunction, Assessed in an Experimental Model

The present project aims to evaluate Tribulus terrestris (TT) extracts by addressing various possible mechanisms of action in order to see whether the use of TT supplements in diabetes and diabetes complications is justified. Diabetic rats were divided into three groups: diabetic control group, TT extract with low protodioscin content group (TT-LPC) and TT extract with high protodioscin content group (TT-HPC). After twelve weeks of treatment, fasting blood glucose, insulin, LH, FSH and testosterone levels were measured. Both TT preparations reduced elevated blood glucose level. Insulin and luteinizing hormone levels were not significantly different compared with the control group; however, the FSH and testosterone levels were significantly higher in the TT-HPC group compared with the diabetic control group. The testosterone level is correlated in part with the protodioscin concentration in extracts and is probably mediated through an FSH-linked pathway.

Use of proteomics to detect sex-related differences in effects of toxicants: implications for using proteomics in toxicology

This review provides an overview of results obtained when using proteome analysis for detecting sex-based differences in response to toxicants. It reveals implications to be taken into account when considering the use of proteomics in toxicological studies. It appears that results may differ when studying the same chemical in the same species in different target tissues. Another result of interest is the limited dose-response behavior of differential abundance patterns observed in studies where more than one dose level is tested. It is concluded that use of proteomics to study differences in modes of action of toxic compounds is an active area of research. The examples from use of proteomics to study sex-dependent differences also reveal that further studies are needed to provide reliable insight in modes of action, novel biomarkers or even novel therapies. To eventually reach this aim for this and other toxicological endpoints, it is essential to consider background variability, consequences of timing of toxicant administration, dose-response behavior, relevant species and target organ, species and organ variability and the presence of proteoforms.

Gender-dimorphic regulation of DJ1 and its interactions with metabolic proteins in streptozotocin-induced diabetic rats

Regulation of DJ1 is associated with a number of human diseases. To determine the involvement of DJ1 in progression of diabetes in a gender-dependent manner, we investigated its tissue-specific expression in streptozotocin (STZ)-induced diabetic male and female rats in this study. In animal experiments, females showed greater susceptibility towards developing diabetes because of lower insulin secretion and higher blood glucose levels as compared to male diabetic rats upon exposure to STZ. Immunoblotting confirmed sexually dimorphic regulation of DJ1 in various metabolic tissues such as the liver, pancreas and skeletal muscle. Immunofluorescence analysis revealed the location as well as reinforced the gender-dependent expression of DJ1 in hepatic tissue. Co-immunoprecipitation assay identified several interacting proteins with DJ1 whose functions were shown to be involved in various metabolic pathways viz. antioxidative and stress defence system, protein and methionine metabolism, nitrogen metabolism, urea metabolism, etc. Using GeneMANIA, a predictive web interface for gene functions, we showed for the first time that DJ1 may regulate T1DM via the JNK1 pathway, suggesting DJ1 interacts with other proteins from various metabolic pathways. We anticipate that the current data will provide insights into the aetiology of T1DM.