SH-SY5Y Cell Line In Vitro Models for Parkinson Disease Research-Old Practice for New Trends.

The SH-SY5Y cell line is a simple and inexpensive in vitro experimental model for studying Parkinson disease (PD). This experimental model is a useful tool for elucidating pathophysiological mechanisms of PD and in the development of new pharmacological therapies. In this review, we aim to summarize current protocols for SH-SY5Y cell culturing and differentiation and PD experimental designs derived from the SH-SY5Y cell line. The most efficient protocol for differentiation of the SH-SY5Y cell line into dopaminergic neurons seems to be the addition of retinoic acid to the growth medium, followed by 12-O-tetradecanoylphorbol-13-acetate (TPA) addition in a low concentration of fetal bovine serum. PD pathological changes, such as neuronal apoptosis and the intraneuronal alpha-synuclein aggregation, can be reproduced in the SH-SY5Y cell line either by the use of neurotoxic agents [such as rotenone, 1-methyl-4-phenylpyridinium (MPP+), 6-hydroxydopamine] or by genetic modification (transfection of the alpha-synuclein wild-type or mutant gene, genetic manipulation of other genes involved in PD). In addition, compounds with a potential neuroprotective role may be tested on neurotoxicity-induced SH-SY5Y models. The cell line can also be used for testing PD pathophysiological mechanisms such as the prion-like neuronal transmission of alpha-synuclein or the microbiota influence in PD. In conclusion, the use of the SH-SY5Y cell line represents a basic but consistent first step in experiments related to PD, but which must be followed by the confirmation of the results through more complex in vitro and in vivo experimental models.

Resistance pattern of multi-drug resistant strains of Mycobacterium tuberculosis and characteristics of patients with multi-drug resistant tuberculosis.

Introduction: Multi-drug resistant tuberculosis (MDR-TB) is a major concern in the medical community. Knowledge about the drug resistance pattern of Mycobacterium tuberculosis strains plays an essential role in the management of the disease. Material and methods: We conducted a retrospective, 3-year study (2009-2011), in an urban area. We collected data on the drug resistance for 497 M. tuberculosis strains, isolated from patients with pulmonary TB. Among the 497 strains, we identified 158 MDR strains. Eighty medical recorders of patients infected with MDR strains were available and we included those patients in the study group. Results: Of the 497 analysed strains, 8% were resistant to a single anti-TB drug. We identified 5.2% polyresistant drug strains, the most frequent combination being INH+EMB (1.4%). Of the 158 MDR strains identified (31.8%), over 60% were resistant to all first line anti-TB drugs tested. Most of them presented resistance to STM (86.1%) and EMB (67.7%). With respect to second line anti-TB drugs resistance to KM (23.4%) was the most common, followed by OFX (8.2%). With respect to the patients with MDR-TB, a percentage of 61.2% of them had a history of anti-TB treatment. Regarding lifestyle habits, 61.2% of the patients were smokers and 18.8% were abusing alcohol. Out of 51 patients, for whom information was available regarding their occupation, only 33.3 % were employees. Conclusion: MDR strains of Mycobacterium tuberculosis display an increased resistance to first line anti-TB drugs. Extension of resistance to second line anti-TB drugs narrows the therapeutic options. Knowledge of MDR-TB risk factors is imperative for the correct and rapid initiation of the treatment.