Pustaka Ilmiah Universitas Padjadjaran

Abstrak

Ekspresi Bcl-2 dan Caspase-3 Pascapaparan Hipoksia Hipobarik Intermiten (Bcl-2 and Caspase-3 Expression Post Exposure of Intermittent Hypobaric Hypoxia)

Hipoksia hipobarik intermiten sering dialami oleh awak pesawat, karena selama di dalam kabin pesawat bernapas dengan tekanan udara yang lebih rendah. Tubuh akan beradaptasi dengan cara mengikat oksigen lebih banyak dan juga mengurangi dampak hipoksia. Fungsi mitokondria akan terganggu pada hipoksia, yaitu permiabilitas membran luar mitokondria karena protein Bcl-2 menurun. Jika hipoksia berlanjut akan terjadi kebocoran membran mitokondria, pelepasan sitokrom-c, dan proses apoptosis berlangsung. Penelitian ini bertujuan menganalisis protein Bcl-2 sebagai antiapoptosis dan caspase-3 sebagai indikator apoptosis akibat paparan hipoksia hipobarik intermiten. Dilakukan penelitian eksperimental pada tikus jantan Spraque Dawley periode Januari–April 2010 dengan melakukan paparan hipoksia hipobarik intermiten satu sampai empat kali dengan interval satu minggu. Jantung tikus dijadikan spesimen untuk dilakukan pemeriksaan ekspresi protein dengan pulasan imunohistokimia di Departemen Patologi Anatomi RS Dr. Hasan Sadikin Bandung dan western blot di Bagian Biomolekuler FK Universitas Indonesia Jakarta. Ekspresi protein Bcl-2 meningkat sesuai dengan frekuensi paparan hipoksia hipobarik intermiten, sebaliknya ekspresi protein caspase-3 menurun (r=-0,448, p=0,013). Dari penelitian ini dapat disimpulkan bahwa terjadi penurunan tingkat apoptosis akibat paparan hipoksia hipobarik intermiten, hal ini disebabkan mekanisme adaptasi natural yang ditandai dengan menurunnya apoptosis sel dan secara tidak langsung akan memberi efek kardioprotektif.

Intermittent hypobaric hypoxia often suffered by cabin crew due to the fact that they are breathing lower pressured air inside the plane cabin. Human body will adapt by binding more oxygen and reducing hypoxia effect. Mitochondria function will be irritated by hypoxia which affect, outer mithochondrial membrane permeability due to decrease of Bcl-2 protein. Later on if hypoxia continues mitochondrial membrane will leaked cytocrome-c will released and apoptotic pathway will occur. The purpose of this study was to analyze Bcl-2 protein as antiapoptosis and caspase-3 as apoptosis indicator of intermittent hypobaric hypoxia exposure. Experimental Study was subjected to Spraque Dawley male mice during January–April 2010 by exposing them to several intermittent hypobaric hypoxias (one to four treatment) in an interval of one week. Protein expression on mice heart cell were detected by immunohistochemistry in the Department of Pathology Anatomy Padjadjaran University-RS Dr. Hasan Sadikin Bandung and western blot methods in Department Biomolecullar Indonesia University Jakarta. Bcl-2 protein expressions increased according with the frequency of intermittent hypobaric hypoxia exposures, while a reverse trend was found for caspase-3 protein expressions (r=-0.448, p=0.013). From the study it can be concluded that apoptosis will be decreased as a result of intermittent hypobaric hypoxia exposures, which occurred from natural adaptation mechanism indicated by decrease of cell apoptosis and cardio protective effect will be emerged.