Neurite Outgrowth of PC12 Mutant Cells Induced by Orange Oil and d-Limonene via the p38 MAPK Pathway

We studied the effects of natural essential oil on neurite outgrowth in PC12m3 neuronal cells to elucidate the mechanism underlying the action of the oils used in aromatherapy. Neurite outgrowth can be induced by nerve growth factor (NGF), where ERK and p38 MAPK among MAPK pathways play important roles in activating intracellular signal transduction. In this study, we investigated whether d-limonene, the major component of essential oils from oranges, can promote neurite outgrowth in PC12m3 cells, in which neurite outgrowth can be induced by various physical stimulations. We also examined by which pathways, the ERK, p38 MAPK or JNK pathway, d-limonene acts on PC12m3 cells. Our results showed that neurite outgrowth can be induced when the cells are treated with d-limonene. After treatment with d-limonene, we observed that p38 MAPK is strongly activated in PC12m3 cells, while ERK is weakly activated. In contrast, JNK shows little activity. A study using an inhibitor of p38 MAPK revealed that neurite outgrowth in PC12m3 cells is induced via the activation of p38 MAPK by d-limonene. The results thus indicate that d-limonene may promote neural cell differentiation mainly via activation of the p38 MAPK pathway

Differential Response of Heat-Shock-Induced p38 MAPK and JNK Activity in PC12 Mutant and PC12 Parental Cells for Differentiation and Apoptosis

Among the 3 mitogen-activated protein kinases -- ERK, p38 MAPK and JNK -- JNK has been suggested to participate in apoptosis, whereas p38 MAPK is thought to be part of the differentiation response. There are many common inducers of JNK and p38 MAPK, but the mechanisms underlying the differential response to apoptosis and differentiation are poorly understood. We found that heatshock activated p38 MAPK at 3min after exposure to a temperature of 44 in stress-hypersensitive PC12m3 mutant cells, while it activated JNK at 20min after the same heat treatment. However, heat shock activated p38 MAPK 5min after heat treatment and JNK 10min after heat treatment in PC12 parental cells. The extent of phosphorylation of p38 MAPK induced by heat shock in PC12m3 cells was significantly greater than that in PC12 parental cells, and a high level of heat-shock-induced neurite outgrowth was observed only in PC12m3 cells. On the other hand, heat-shock-induced JNK activation appeared more quickly and apoptosis started earlier in PC12 parental cells. These findings indicate that short stress induces p38 MAPK and longer stress induces JNK, and that the response of these kinases to heat shock differs depending on cell type.</p

VARIAÇÃO GENÉTICA EM DUAS POPULAÇÕES DE AROEIRA (ASTRONIUM URUNDEUVA-(FR. ALL.) ENGL. - ANACARDIACEAE)

A variação genética entre e dentro de duas populações de aroeira (Astronium urundeuva (Fr. AlI.) - Engl.- Anacardiaceae) é fornecida, para as características: altura e florescimento, obtidas a partir de dois testes de progênies, com 4 anos de idade, originários de duas populações, instalados em Selvíria-MS. Para altura houve diferença na média das duas populações a partir do terceiro ano, sendo que o IMA foi de 0,97 m e 0,92 rn, para as populações de Bauru e Selvíria, respectivamente. Já para florescimento, as populações se diferenciaram quanto aos florescimentos total, masculino, femini- :.no e plantas sem florescimento. O controle genético destas duas características (altura e florescimento) foi baixo, devido à fase juvenil das plantas

細胞の三次元様増殖を指標とした温熱療法の最適条件に関する研究

本研究の目的は、三次元様増殖に温熱刺激が効果的に働く最適量と最小量を示すことであった。C3H10T1/2マウス線維芽細胞とハイドロキシアパタイトを混合し、設定温度が40℃・41.5℃・43℃・44℃・45℃、処理時間は2分間・10分間・15分間・20分間・30分間・45分間・60分間・90分間・180分間・360分間の温熱刺激を与えて10週間培養することにより三次元様増殖形成に必要な最小と最適な温熱量を調べた。その結果、三次元様増殖形成に必要な最小の温熱量は43℃2分間、また最適な温熱量は43℃10分間であった。43℃2分間は非処理対照の1.7倍、43℃10分間では3.7倍と非常に高い形成率となり、それぞれ有意差がみられた(p<0.05)。また、40℃で90分間・180分間と41.5℃15分間および44℃10分間も対照群に比べ高い形成率であった。43℃10分間の温熱処理では1週間後に約80%がアポトーシスになっていた。ウエスタンブロット分析により43℃10分間の温熱処理によってp38 MAPK の活性化が明らかであった。これらの結果から、温熱刺激による三次元様増殖はp38 MAPK の経路を介していることが判明した。本研究結果は最適な温熱量を提示するものとして温熱療法の基礎となり、温熱療法の効果を細胞生物学的に示すための重要な知見になると考えられる