Hibiscus sabdariffa Linn. (roselle) is a polyphenol rich fruit. This study aimed to identify the neuroprotective effect of roselle on LPS-induced cell proliferation and nitric oxide-induced free radical in microglia and neuroblastoma cells. MTT assay was used to identify the appropriate concentration of roselle and LPS for microglia and neuroblastoma cells proliferation study. Griess assay were used to determine the level of nitric oxide accumulated based on the reaction of Griess to estimate the activity of iNOS in nitric oxide production. The results showed that roselle at the concentration of 50 μg/mL and 100 μg/mL and LPS at concentration of 1 μg/mL does not give cytotoxic effect towards microglia C8-B4 and neuroblastoma LN18 cells. The roselle treatment at 50 μg/mL and 100 μg/mL showed a protective effect on LPS-induced microglia C8-B4 cells. However, in neuroblastoma LN18 cells, no protective effect was seen on both 50 μg/mL and 100 μg/mL of roselle treatment following induction with 1 μg/mL of LPS. On the other hand, the production of nitric oxide (NO) was reduced when LPS-induced microglia C8-B4 cells were treated with 50 μg/mL of roselle. Treatment of roselle at concentration 100 μg/mL on LPS-induced neuroblastoma LN18 cells also reduced the production of nitric oxide. As a conclusion, roselle had the ability to give neuroprotective effect by the inhibition of LPS induction activity on microglia activation for normal and cancer cells at different concentrations.
Hibiscus

Background: Simvastatin is usually taken in the evening due to the circadian rhythm of hepatic cholesterol biosynthesis. The degree of reduction of low-density lipoprotein cholesterol (LDL-C) and the level of adherence to different administration time remained unknown in the Malaysian population. This study aims to investigate the effect of simvastatin on the percentage changes of lipid profile and the level of adherence to when simvastatin was instructed to be taken at different timing. Methods: Nine primary care health clinics across Malaysia participated in this study. 147 statin-naive subjects were selected through convenient sampling and randomised into one of the three arms (after breakfast, after dinner or before bedtime). Differences on percentage reduction of LDL-C from baseline and level of adherence among the three groups at week-16 were compared. The main outcomes measured in this study were the percentage change of lipid parameters and the percentage of high-adherence (MMAS=8) at week-16. Results: 59.2% of the patients were male. The mean age of the study population was 53.93± 10.85 years. Most of the patients were Malays (69.4%); followed by Indians (22.4%) and Chinese (8.2%). LDL-C decreased from 4.26 (Standard Deviation, SD1.01) to 2.36 (SD0.69)mmol/L at week-16 for patients taking simvastatin before bedtime; an absolute reduction of 44.95%.The differences of LDL-C percentage reduction between three arms were significantly different (p<0.001). The greatest LDL-C reduction was observed when simvastatin was taken before bedtime and revealed 56.2% patients with high-adherence at week-16. Conclusion: Simvastatin showed superior LDL-reduction and higher level of adherence when being instructed to be taken before bedtime