探討 Lactobacillus paracasei subsp. paracasei NTU 101 與 Lactobacillus plantarum NTU 102 對不易形成體脂肪及降低高脂飲食誘發體內發炎之影響

Abstract

肥胖為引起許多代謝相關慢性疾病，如高血壓、高血脂、二型糖尿病及代謝症候群等之危險因子，故隨著肥胖人口不斷增加，如何有效降低體脂肪與減緩肥胖為當務之急事。本研究分別利用體外試驗及體內試驗評估先前所分離出之兩株本土乳酸菌 Lactobacillus paracasei subsp. paracasei NTU 101 (NTU 101) 與 Lactobacillus plantarum NTU 102 (NTU 102) 及其發酵豆奶產物 (SM 101 與SM 102) 對不易形成體脂肪及降低體脂肪生成之影響。體外試驗以 3T3-L1 前脂肪細胞株為材料，分別探討活菌及其發酵豆奶上清液對前脂肪細胞增生、分化之影響，並分析其對促進成熟脂肪細胞進行脂解 (lipolysis) 及細胞肝素釋放脂蛋白脂解酶活性 (heparin-releasable lipoprotein lipase, HR-LPL) 之作用。體內試驗以同時餵食雄性 Wistar 大鼠高油脂飼料與兩株乳酸活菌及其發酵豆奶產物，經 5 週飼養後利用各項評估指標判定其減少及降低體脂肪生成之效果。體外實驗結果顯示，NTU 101, NTU 102, SM 101 與 SM 102 皆具有抑制前脂肪細胞增生、分化之效果，最高抑制率分別為 26.8% 及 53.1%，其中以活菌處理效果較佳。處理 SM 101 與 SM 102 後具顯著促進成熟脂肪細胞進行 lipolysis 及抑制 HR-LPL 之活性，最高增加率與抑制率分別為 26.4% 及 30.4%，皆以 SM 101 效果較佳。體內實驗結果顯示，在不減少攝食量與熱量攝取之情下，投予 NTU 101, NTU 102, SM 101 與 SM 102 具降低飼料效率、體重與體脂肪重量之效果，由其以 SM 101 效果最佳，最高降低率分別為 53.2%, 49.7% 及 55.9%。而投予兩株乳酸菌發酵豆奶能促進脂肪細胞進行 lipolysis 及抑制 HR-LPL 之活性，最大增加率與抑制率分別為 39.6% 及 26.4%，並具減少脂肪細胞平均半徑與減少大脂肪細胞及增加小脂肪細胞數目之效果。在血清脂質指標方面，活菌及 其豆奶發酵產物除了能顯著降低 TG, TC, LDL-C 含量與 LDL-C/HDL-C 比值外，也能顯著降低血清中促發炎細胞激素與內毒素之濃度。最後，本研究體外及體內實驗結果皆顯示投予兩株乳酸菌及其發酵豆奶後，皆具顯著抑制因攝食高脂飼料所產生之體內發炎並有降低及不易形成體脂肪之功效。

Obesity is associated with high risk for developing cardiovascular disease, metabolic syndrome and diabetes. In this study, we used the 3T3-L1 cell line as an in vitro model to examine the effects of Lactobacillus paracasei subsp. paracasei NTU 101, Lactobacillus plantarum NTU 102 and its’ fermented soy skim milk supernatant on proliferation and differentiation in preadipocyte as well as lipolysis and heparin-releasable lipoprotein lipase activity in mature adipocyte. Furthermore, we investigated the anti-obesity effects of NTU 101, NTU 102 and its fermented soy skim milk (SM101 and SM102) supplemented with high-fat diet on rats for five weeks as an in vivo animal model. As results in cellular experiment, NTU 101, NTU 102 and its’ fermented soy skim milk supernatant inhibited the proliferation and differentiation of 3T3-L1 preadipocyte, the inhibitory effects of NTU 101 and NTU 102 were better than its’ fermented products, the repression ratio was 26.8% and 53.1%, respectively. NTU 101 and NTU 102 fermented soy milk supernatant also significantly induced lipolysis and inhibited heparin-releasable LPL activity in adipocyte, the elevation and inhibition ratio of NTU 101 fermented products were 26.4% and 30.4%, respectively. In animal experiment, high-fat diet supplemented with NTU 101, NTU 102, SM101 and SM102 can significantly decrease feed efficiency, body weight and body fat pad weight of rats, the decrease ratio in SM101 was 53.2%, 49.7% and 55.9%, respectively. Moreover, fermented soy skim milk not only significantly induced lipolysis and inhibited heparin-releasable LPL activity in adipocyte, but also reduced average radius of adipocyte and increased the numbers of small size adipocyte. On the other hand, supplemented with NTU 101, NTU 102, SM101 and SM102 decreased serum lipidic parameters, proinflammatory cytokines and endotoxin in rats. These results revealed NTU 101, NTU 102 and its’ fermented soy skim milk may have the ability to inhibit inflammation induced by high-fat diet and reduce or prevent of body fat accumulation.