当人体发生严重的疾病时，例如多器官功能衰竭和败血症时，经常会发生缺血性肾脏损伤。由于输送到肾脏的氧气、营养物质等急剧减少，于是肾上皮细胞发生了缺血-再灌注损伤，产生了急性缺血性肾脏损伤，从而导致全身水潴留、电解质失衡，代谢废物不能顺利排出。
很不幸的是，目前针对急性肾脏损伤的治疗只是支持性的，目前尚无有效的治疗药物。目前所用的一些药物（例如：多巴胺、奈西立肽/nesiritide、非诺多巴/fenoldopam、甘露醇）不仅对急性肾脏损伤无益，在某些情况下反而是有害的。
人参皂苷Rb1是人参中的主要成分之一，目前发现Rb1具有广泛的生理活性，例如免疫调节、促进骨质形成、关节保护等。最近，科学家们发现预先服用Rb1能够有效地减轻急性肾脏损伤。
研究人员首先给予小鼠服用人参皂苷Rb1，然后制造急性肠缺血，从而诱导产生急性肾损伤。然后，研究人员评估肾脏损伤的严重程度。研究人员惊奇地发现，当给予Rb1预先治疗后，急性肾脏损伤的严重程度大大降低，例如血液中的尿素氮、肌酐水平降低，反映肾脏细胞凋亡的指标NGAL也明显降低。同时病理检查也发现，肾脏的病理损害也显著降低。
这个研究显示人参皂苷Rb1具有肾脏保护作用，为临床治疗提供了一个潜在的治疗药物。
Related Articles:
Protective Effect of Ginsenoside Rb1 against Intestinal Ischemia-Reperfusion Induced Acute Renal Injury in Mice.
PLoS One. 2013;8(12):e80859
Authors: Sun Q, Meng QT, Jiang Y, Liu HM, Lei SQ, Su WT, Duan WN, Wu Y, Xia ZY, Xia ZY
Abstract
Ginsenoside Rb1 (RB1), the most clinically effective constituent of ginseng, possesses a variety of biological activities.
The objectives of this study were to investigate the protective effects of RB1 and its underlying mechanism on renal injury induced by intestinal ischemia-reperfusion (IIR) in mice.
RB1 was administered prior to inducing IIR achieved by occluding the superior mesenteric artery for 45 min followed by 120 min of reperfusion. All-trans-retinoic acid (ATRA) was used as an inhibitor of NF-E2-related factor-2 (Nrf2) signaling.
Adult male C57BL/6J mice were randomly divided into six groups:
- sham group
- IIR group
- RB1 group
- sham + ATRA group
- IIR + ATRA group
- RB1 + ATRA group
Intestinal histology and pathological injury score were observed. Intestinal mucosal injury was also evaluated by measuring serum diamine oxidase (DAO). Renal injury induced by IIR was characterized by increased levels of histological severity score, blood urea nitrogen (BUN), serum creatinine (Scr) and neutrophil gelatinase-associated lipocalin (NGAL), which was accompanied with elevated renal TUNEL-positive cells and the Bcl-2/Bax expression ratio.
RB1 significantly reduced renal injury and apoptosis as compared with IIR group, which was reversed by ATRA treatment. Immunohistochemistry and Western blot analysis demonstrated that RB1 significantly upregulated the protein expression of heme oxygenase-1 (HO-1) and Nrf2, which were attenuated by ATRA treatment.
Taken together, these results suggest that the protective effects of RB1 pretreatment against renal injury induced by IIR are associated with activation of the Nrf2/ anti-oxidant response element (ARE) pathway.
PMID: 24324637 [PubMed – in process]
Source: Dammarane Saponins
