The flavonoid luteolin reduces mutant huntingtin aggregation and cytotoxicity in huntingtin-mutated neuroblastoma cells

Background

Huntington's disease is an inherited progressive neurodegenerative disorder caused by an expansion of the polyglutamine tract leading to malformation and aggregation of the mutant huntingtin protein in the cell cytoplasm and nucleus of affected brain regions. The development of neuroprotective agents from plants has received considerable research attention.

Objective

Our study aims to investigate the neuroprotective effects of luteolin and the mechanisms that underline its potential mediated protection in the mutant htt neuroblastoma cells.

Methods

The mutant htt neuroblastoma cells were transfected with 160Q, and the control wild-type neuroblastoma cells were transfected with 20Q htt for 24 h and later treated with luteolin. Cell viability was determined by MTT and PI staining in both groups, while western blotting was used to evaluate caspase 3 protein expression. Aggregation formation was assessed via immunofluorescence microscopy. Also, western blotting was utilized to measure the protein expression of mutant htt aggregated and soluble protein, Nrf2 and HO-1. The impact of Nrf2 on luteolin-treated neuroblastoma cells was assessed using small interfering RNAs.

Results

Our study reports that luteolin can protect cultured cells from mutant huntingtin cytotoxicity, evidenced by increased viability and decreased apoptosis. Also, luteolin reduced the accumulation of soluble and insoluble mutant huntingtin aggregates in mutant htt neuroblastoma cells transfected with 160Q compared to the control wild-type. The mutant htt aggregate reduction mediated by luteolin appeared to be independent of the Nrf2 -HO-1 antioxidant pathway.

Conclusion

Luteolin presents a new potential therapeutic and protective agent for the treatment and decreasing the cytotoxicity in neurodegenerative diseases such as Huntington's disease.

Campus Teaching of Clinical Dermatology Compared to Hospital Teaching to Medical Students of Almaarefa University, Riyadh, Saudi Arabia

Introduction: Clinical teaching is the cornerstone of medical student teaching and training. Undoubtedly, the objective teaching is of great benefit to the students; on the other hand, many offenders let the hospital-based teaching lose this objectivity. Aim: The goal was to assess clinical teaching outcomes on campus and in hospitals. Methods: This is a descriptive and retrospective study. The students' results in the final clinical part of the dermatology examination have been used as a comparative indicator. The means of the final examination results were calculated for all students who sat for dermatology exams from 2013 to 2016, stratified by campus group (2013–2014) and hospital group (2015–2016). Results: The means for both groups have been calculated and compared. The P-value showed a significant statistical difference between the two groups, which is supported by calculating the coefficient of variation to cancel the effect of inequality in students’ numbers between the two groups. Conclusion: Regardless of the differences, it is clear that classrooms teaching using real, selected cases and projected case scenarios are extremely promising under well-prepared conditions.