Disertasi

Efek Kemopreventif Andrografolida Nanoemulsi terhadap Promosi Karsinogenesis Kulit Tikus yang Diinduksi oleh DMBA dan Narrowband Ultraviolet B: Kajian terhadap Proses Inflamasi, Proliferasi, dan Apoptosis. = Chemopreventive Effect of Andrographolide Nanoemulsion on the Promotion Stage of Rat Skin Carcinogenesis Induced by DMBA and Narrowband Ultraviolet B: A Study ofInflammation, Proliferation, and Apoptosis.

Latar belakang: Karsinoma sel skuamosa (KSS) merupakan kanker kulit nonmelanoma dengan insidensi yang terus meningkat secara global. Pajanan sinar ultraviolet B (UVB) secara kronis merupakan faktor risiko utama KSS, dan berperan krusial pada fase promosi fotokarsinogenesis kulit. Hingga saat ini, pilihan tata laksana nonbedah untuk mengatasi KSS masih terbatas. Oleh karena itu, pencegahan KSS khususnya melalui pemanfaatan senyawa aktif dari bahan alam, perlu ditingkatkan. Andrografolida, senyawa aktif dari tanaman Andrographis paniculata, memiliki potensi kemopreventif melalui aktivitas antiinflamasi, antioksidan, dan antikanker. Namun, pemanfaatannya secara topikal masih terbatas karena kelarutan dalam air rendah. Penggunaan sistem penghantaran obat berbasis nanoemulsi diharapkan dapat meningkatkan penetrasi serta efektivitas kemopreventif andrografolida pada kulit. Penelitian ini bertujuan untuk membuktikan efek kemopreventif andrografolida nanoemulsi (AG-NE) terhadap fase promosi karsinogenesis kulit melalui proses inflamasi, proliferasi, dan apoptosis. Metode: Sebanyak 28 tikus Wistar jantan dibagi ke dalam tujuh kelompok yang meliputi kontrol negatif (KN), DMBA, kontrol perlakuan (KP), serta kelompok uji (BNE-1x, AG-NE-1x, AG-NE-2x, AG-NE-3x). Induksi promosi karsinogenesis dilakukan dengan pemberian DMBA topikal dosis tunggal dan pajanan NB-UVB selama 10 minggu. Evaluasi gambaran makroskopik, histopatologik (pewarnaan hematoksilin-eosin), dan analisis molekuler terhadap kadar MDA (kolorimetri), CPD, NFkB, TNF-α, IL-6, IL-12, IL-10, IL-11 (ELISA), ekspresi Ki-67 (imunohistokimia), ekspresi mRNA (qRT-PCR), protein (western blot), serta aktivitas caspase-3 (kolorimetri) kulit dilakukan di minggu ke-10 Hasil: Pemberian AG-NE dapat menekan keparahan lesi dan hiperplasia epidermis, memodulasi sitokin inflamasi, serta menekan ekspresi NFkB dan Ki-67, yang disertai dengan peningkatan aktivitas caspase-3. Kesimpulan: AG-NE topikal menunjukkan potensi sebagai agen kemopreventif pada fase promosi karsinogenesis kulit melalui mekanisme antiinflamasi, antiproliferatif, dan proapoptosis.
Kata kunci: andrografolida nanoemulsi, apoptosis, fase promosi, inflamasi, NBUVB, proliferasi


Background: Squamous cell carcinoma (SCC) is a nonmelanoma skin cancer with an increasing global incidence. Chronic exposure to ultraviolet B (UVB) radiation is a major contributing factor, particularly during the promotion phase of skin photocarcinogenesis. Currently, non-surgical treatment options for SCC remain limited, emphasizing the need for effective strategies, particularly those utilizing natural bioactive compounds. Andrographolide, a major active compound from Andrographis paniculata, has demonstrated chemopreventive potential through its anti-inflammatory, antioxidant, and anti-cancer activities. However, its poor water solubility limits its topical use. A nanoemulsion-based delivery system may improve its skin penetration and chemopreventive activity. This study aimed to validate the chemopreventive effect of andrographolide nanoemulsion (AG-NE) on the promotion phase of skin carcinogenesis, by targeting inflammation, proliferation, and apoptosis. Method: Twenty-eight male Wistar rats were divided into seven groups, consisting of a negative control (KN), DMBA, treatment control (KP), and four treatment groups (BNE-1x, AG-NE-1x, AG-NE-2x, and AG-NE- 3x). The promotion phase of skin carcinogenesis was induced using DMBA topical and NB-UVB exposure over ten weeks. At week 10, macroscopic and histopathological (hematoxylin-eosin staining) evaluations were performed, along with molecular analyses including MDA level (colorimetry); CPD, NFκB, TNF- ⍺, IL-6, IL-12, IL-10, IL-11 (ELISA), Ki-67 expression (immunohistochemistry), mRNA expression (qRT-PCR); protein expression (western blot); and caspase-3 activity (colorimetry). Results: AG-NE treatment reduced skin lesion severity and epidermal hyperplasia, modulated inflammatory cytokine levels, downregulated NFkB and Ki-67 expression, and increased caspase-3 activity. Conclusion: Topical administration of AG-NE shows potential as a chemopreventive agent during the promotion phase of skin carcinogenesis, possibly through anti-inflammatory, antiproliferative, and proapoptotic mechanisms.
Keywords: andrographolide nanoemulsion, apoptosis, promotion phase, inflammation, NB-UVB, proliferation