The Indonesian Biomedical Journal

73-7

Authors: Asri Hendrawati

BACKGROUND: Increasing free radicals and oxidative stress due to chronic hyperglycemia in type-2 diabetes mellitus (DM) promotes the activity of endogenic antioxidative genes. Nuclear factor erythroid 2-related factor 2 (Nrf2) expression and activity are important to regulate the production of endogenic antioxidative enzymes. CONTENT: Normally, Nrf2 is bound by protein Kelchlike ECH-associated protein-1 (Keap1) in the cytosol. Stimulation from oxidative stress causes the release of Nrf2 from Keap1. When activated, Nrf2 enters the nucleus and activates the antioxidant response element (ARE). This will further increase the production of antioxidative enzymes, such as catalase, nitrite oxydase and heme oxygenase-1. The discovery of oxidative stress, as the cause of complications in DM, gives rise to the idea of developing a treatment which can increase the expression and activity of Nrf2, one of which is a flavonoid antioxidant. SUMMARY: Currently, nuclear factor erythroid 2-related factor 2 is an important target in the therapy of DM.

84-90

Authors: Djaja Rusmana, Roro Wahyudianingsih, Mariska Elisabeth, Balqis, Maesaroh, Wahyu Widowati

BACKGROUND: Normal metabolism of oxygen and exogenous factors constantly generate free radicals which could be harmful to the human body. Human need antioxidants to provide protection against free radicals, thus plants are a good source of natural antioxidants. Phyllanthus niruri (P. niruri) has been known to possess several medicinal properties and contain numerous active phytochemical. In this research, we conducted phytochemical screening and antioxidant assay of P. niruri extract along with the compounds rutin and quercetin, which are flavonoids possessing medicinal properties. This study was conducted to determine P. niruri, rutin and quercetin as antioxidant. METHODS: In this study, qualitative phytochemical screening was performed to detect phenol, flavonoid, saponin, tannin, steroid/triterpenoid, terpenoid and alkaloid in P. niruri extract. Antioxidant analysis of P. niruri, rutin and quercetin was conducted using total measured phenolic content, 2,2-diphenyl-1-picrylhydrazil (DPPH), 2,2’-azinobis-3-ethylbenzo-thiazoline-6-sulfonic acid (ABTS) and ferric reducing antioxidant power (FRAP) assays. RESULTS: The study revealed that P. niruri extract contained saponin, phenol, flavonoid and tannin based on phytochemical screening. In DPPH and ABTS assays quercetin possessed highest antioxidant activity with IC50 value of 0.55 and 1.17 μg/ml respectively. Meanwhile, P. niruri extract showed the highest FRAP activity which was 373.95 μM Fe(II)/μg extract. Rutin possessed the lowest antioxidant activity in all antioxidant assays. CONCLUSION: This study confirmed that P. niruri extract and quercetin have great potential as a natural antioxidant source.

99-105

Authors: Yenny Surjawan, Hwee Lian Tan, Rahajuningsih Dharma Setiabudy, Wiwik Rositawati

BACKGROUND: The mutation spectrums of hemoglobinopathy are different among populations that yield a different result of erythrocyte indices. Calculation of erythrocyte indices with some formula has been reported to differentiate between hemoglobinopathy and non-hemoglobinopathy, but its cut-off should be recalculated specific for each population to gain a better sensitivity and specificity. We aimed to evaluate red blood cell count (RBC), Mentzer index, red cell distribution width (RDW), RDW index (RDWI), Shine and Lal index (S&L) and Green and King index (G&K) to screen hemoglobinopathy in Indonesia. METHODS: A retrospective cross-sectional study was performed on 202 subjects. The diagnosis of hemoglobinopathy was determined based on the results of complete blood count (CBC) data, high-performance liquid chromatography (HPLC) and Hemoglobin H (HbH) inclusion body. The ferritin concentration was checked to determine the status of iron. The erythrocytes indices were analyzed and calculated to predict hemoglobinopathy. RESULTS: A total 202 subjects who met the criteria were involved in this study. Fifty percent showed pure hemoglobinopathy and 4% showed a combination of thalassemia and hemoglobinopathy. The hemoglobin concentration and RBC were significantly higher, and the mean corpuscular volume (MCV) and RDW were significantly lower in hemoglobinopathy compared to iron deficiency. The difference was not significant if the hemoglobinopathy was combined with iron deficiency. By this study's cut-off, the G&K and RDWI showed the highest accuracy, sensitivity, and specificity. CONCLUSION: The new cut-off of erythrocyte index and its calculation to screen hemoglobinopathy in Indonesia showed a higher sensitivity and specificity, especially for G&K and RDWI with cut-off 73 and 228, respectively. The presence of iron deficiency in hemoglobinopathy could decrease the sensitivity.