Transgenic plant cells as source of hepatoprotective drugs. Alcoholic liver damage (ALD) is among the ten most common causes of death in the USA. The liver may be uniquely sensitive because it metabolizes ethanol at a high rate. This generates acetaldehyde intracellularly, damaging cell components directly, and/or inducing apoptotic cell death. Although some plant natural products are protective it would be of value to discover agents with greater efficacy against ALD. Here, a novel biotechnology, based on selection of mutant plant cells for resistance to alcohol, followed by high throughput pharmacological screening (HTPS) of extracts from surviving cells, is applied to this problem. The mutant population will be generated by activation tagging mutagensis, and extracts from the resulting alcohol-resistant clonal cultures screened for protection of hepatocyte cultures against ethanol-induced damage. However, because plant cells in culture metabolize ethanol to a very limited extent, we propose first to produce transgenic plant lines (N tabacum) over-expressing the activated gene for plant or mammalian ADH. Cell cultures derived from these plants will be evaluated for similarities to mammalian liver cells in metabolism of ethanol to acetaldehyde. Phase 1 is the creation of these ADH-expressing (ADHE) lines. In subsequent phases, hepatoprotective compounds from resitant clonal extracts will be tentatively identified by GC/MS. Regardless of whether novel compounds are discovered, the ADHE plant lines, and the ethanol resistant clonal cultures are patentable and represent a valuable resource for development of alcohol-related medications in the future.
