Protective effects of 4-phenylbutyrate derivatives on the neuronal cell death and endoplasmic reticulum stress.

Abstract

Endoplasmic reticulum (ER) stress responses play an important role in neurodegenerative diseases. Sodium 4-phenylbutyrate (4-PBA) is a terminal aromatic substituted fatty acid that has been used for the treatment of urea cycle disorders. 4-PBA possesses in vitro chemical chaperone activity and reduces the accumulation of Parkin-associated endothelin receptor-like receptor (Pael-R), which is involved in autosomal recessive juvenile parkinsonism (AR-JP). In this study, we show that terminal aromatic substituted fatty acids, including 3-phenylpropionate (3-PPA), 4-PBA, 5-phenylvaleric acid, and 6-phenylhexanoic acid, prevented the aggregation of lactalbumin and bovine serum albumin. Aggregation inhibition increased relative to the number of carbons in the fatty acids. Moreover, these compounds protected cells against ER stress-induced neuronal cell death. The cytoprotective effect correlated with the in vitro chemical chaperone activity. Similarly, cell viability decreased on treatment with tunicamycin, an ER stress inducer, and was dependent on the number of carbons in the fatty acids. Moreover, the expression of glucose-regulated proteins 94 and 78 (GRP94, 78) decreased according to the number of carbons in the fatty acids. Furthermore, we investigated the effects of these compounds on the accumulation of Pael-R in neuroblastoma cells. 3-PPA and 4-PBA significantly suppressed neuronal cell death caused by ER stress induced by the overexpression of Pael-R. Overexpressed Pael-R accumulated in the ER of cells. With 3-PPA and 4-PBA treatment, the localization of the overexpressed Pael-R shifted away from the ER to the cytoplasmic membrane. These results suggest that terminal aromatic substituted fatty acids are potential candidates for the treatment of neurodegenerative diseases.

• Authors: Seisuke Mimori, Yasunobu Okuma, Masayuki Kaneko, Koichi Kawada, Toru Hosoi, Koichiro Ozawa, Yasuyuki Nomura, Hiroshi Hamana
• Journal: Biological & pharmaceutical bulletin (Biol Pharm Bull) Vol. 35 Issue 1 Pg. 84-90 ( 2012) ISSN: 1347-5215 [Electronic] Japan
• PMID: 22223342 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Endoplasmic Reticulum Chaperone BiP
• Fatty Acids, Volatile
• Heat-Shock Proteins
• Membrane Glycoproteins
• Neuroprotective Agents
• Phenylbutyrates
• Phenylpropionates
• Serum Albumin
• endoplasmin
• Tunicamycin
• 3-phenylpropionic acid
• Carbon
• 4-phenylbutyric acid
• Lactalbumin

Topics

• Animals
• Carbon (chemistry)
• Cattle
• Cell Death (drug effects)
• Cell Line, Tumor
• Cell Survival (drug effects)
• Endoplasmic Reticulum Chaperone BiP
• Endoplasmic Reticulum Stress (drug effects)
• Fatty Acids, Volatile (chemistry, pharmacology)
• Heat-Shock Proteins (metabolism)
• Humans
• Lactalbumin (chemistry)
• Membrane Glycoproteins (metabolism)
• Neuroblastoma
• Neurodegenerative Diseases (drug therapy, metabolism)
• Neurons (drug effects, metabolism)
• Neuroprotective Agents (pharmacology, therapeutic use)
• Nuclear Envelope (metabolism)
• Phenylbutyrates (pharmacology, therapeutic use)
• Phenylpropionates (pharmacology)
• Serum Albumin (chemistry)
• Tunicamycin (pharmacology)