Skripsi

Aktivitas Antioksidan α-mangostin terhadap Biomarker Stres Oksidatif pada Hati Tikus dengan Diabetes Mellitus Tipe 2 = Effects of α-mangostin on Oxidative Stress Biomarkers in Type 2 Diabetes Mellitus Induced Rat’s Liver.

Latar belakang: Kondisi hiperglikemi pada diabetes mellitus dapat menyebabkan kondisi stres oksidatif akibat ketidakseimbangan senyawa-senyawa oksidan dan antioksidan. Pada hati, komplikasi terparah dari stres oksidatif tersebut adalah nonalcoholic fatty liver disease (NAFLD). Hingga saat ini, metformin merupakan drug of choice pada pengobatan diabetes mellitus tipe 2 (DMT2), namun dapat menimbulkan efek samping yang menurunkan kepatuhan berobat pasien seperti mual, muntah, dan diare. Oleh karena itu, diperlukan alternatif metformin yang menghasilkan efek serupa dan tidak menimbulkan efek samping yang tidak nyaman. Tujuan: Penelitian ini bertujuan untuk menilai aktivitas antioksidan α-mangostin terhadap kadar malondialdehid (MDA) dan gluation (GSH) hati tikus dengan DMT2 sebagai kandidat obat untuk menangani stres oksidatif pada DMT2. Metode: Penelitian dilakukan terhadap tikus jantan galur Wistar yang berusia 10- 12 minggu dan dibagi menjadi enam kelompok uji: normal, normal + α-mangostin 200mg/kgBB, DMT2, DMT2 + metformin 200mg/kgBB, DMT2 + α-mangostin 100mg/kgBB, DMT2 + α-mangostin 200mg/kgBB. Kelompok DMT2 diinduksi dengan diet tinggi lemak dan glukosa, lalu diinjeksi streptozotocin. Kadar MDA dan GSH kemudian diukur dengan kit pemeriksaan pada jaringan hati yang telah disimpan di suhu -80°C setelah tikus-tikus di-sacrifice. Hasil: α-mangostin dengan dosis 100 mg/kgBB dapat dengan signifikan menurunkan kadar MDA (p=0.038 vs DMT2) dan meningkatkan kadar GSH (p=0.029 vs DMT2), serta memberikan hasil paling baik dalam hal selisih kadar kedua biomarker tersebut dibandingkan keadaan DMT2. Di sisi lain, α-mangostin dengan dosis 200 mg/kgBB dapat meningkatkan kadar GSH secara signifikan (p=0.029 vs DMT2), dosis tersebut juga mampu menurunkan kadar MDA namun secara insignifikan (p=0.143 vs DMT2). Simpulan: Penelitian ini menunjukkan bahwa α-mangostin mampu mempengaruhi kadar MDA dan GSH pada hati tikus dengan DMT2. Sebaiknya dilakukan penelitian lanjutan untuk mencari tahu aktivitas α-mangostin terhadap biomarker stres oksidatif ataupun senyawa lainnya.
Kata kunci: DMT2, α-mangostin, hati, biomarker stres oksidatif


Background: The hyperglycaemic condition occuring in diabetes mellitus causes an imbalance of oxidants and antioxidants, leading to oxidative stress. In the liver, the worst possible complication of oxidative stress is non-alcoholic fatty liver disease (NAFLD). Up to this moment, metformin is the drug of choice for treating type 2 diabetes mellitus (T2DM), but it could disrupt the patient’s compliance due to a possibility of causing nausea, vomiting, dan diarrhoea. Therefore, a search for an alternative drug of metformin with equal efficacy and without the discomfort of its side effects needs to be done. Objective: This study aims to investigate the antioxidant activity of α-mangostin towards malondialdehyde (MDA) and glutathione (GSH) levels in the liver of T2DM rats as a candidate drug for treating oxidative stress in T2DM. Methods: Research is conducted with male Wistar rats (10-12 weeks of age) that were separated into six groups: normal, normal + α-mangostin 200mg/kgBW, T2DM, T2DM + metformin 200mg/kgBW, T2DM + α-mangostin 100mg/kgBW, T2DM + α-mangostin 200mg/kgBW. T2DM groups were induced with high fat and high glucose diet, then injected with streptozotocin. The rats were then sacrificed and the liver tissues are refrigerated at -80°C, in which MDA and GSH levels were obtained by using the appropriate assay kit. Results: α-mangostin with an administration dose of 100mg/kgBW significantly reduces MDA levels (p=0.038 vs T2DM) and increases GSH levels (p=0.029 vs T2DM), with also the best results (most difference in biomarker levels in contrast with the T2DM group). On the other hand, α-mangostin with an administration dose of 200mg/kgBW was able to significantly increase the level of GSH (p=0.029 vs T2DM), this dosage was also able to lower MDA level, though insignificant (p=0.143 vs T2DM). Conclusion: This study shows that α-mangostin is able to lower MDA level and increase GSH level in the liver of T2DM rats. It is recommended to continue researching to find out the activity of α-mangostin towards other oxidative stress biomarkers or substances.
Key words: T2DM, α-mangostin, liver, oxidative stress biomarkers