[Effect of electroacupuncture on renal aging and renal phosphatidylinositide 3-kinase/protein kinase B signaling in aging mice].

Abstract

Objectives: To observe the effect of electroacupuncture (EA) at "Baihui"(GV20) and"Shenshu"(BL23) on the morphological changes of aging kidney and phosphatidylinositol 3-kinase /protein kinases B (PI3K/Akt) signaling in SAMP8 mice, so as to explore its mechanisms of delaying renal aging.

Methods: A total of 20 seven-month-old male SAMP8 mice were randomly divided into model group and EA group, with 10 mice in each group. The normal group consisted of 10 male SAMR1 mice with the same age. In the EA group, acupuncture was performed at GV20 and bilateral BL23 respectively. EA (2 Hz, 1 mA) was applied to bilateral BL23 for 15 min every time, once a day, 10 days as a course for a total of 4 courses, the interval between courses was one day. The general condition of the mice in each group was observed during the intervention period. After the intervention, H.E. staining was used to observe the morphological changes of aging kidney. Masson staining was used to evaluate the degree of renal fibrosis. The relative protein expression levels of alpha smooth musle action (α-SMA), interleukin-1β (IL-1β), interleukin-4 (IL-4), PI3K and Akt in renal tissue were detected by Western blot.

Results: Compared with the normal group, mice in the model group showed dull hair, reduced daily activity and food and water intake, and poor response to external stimulation, and the relative protein expression levels of α-SMA, IL-1β, PI3K and Akt in renal tissue were significantly increased (P<0.001, P<0.05, P<0.01), while the protein expression level of IL-4 was significantly decreased (P<0.01). After EA intervention, compared with the model group, the general condition of rats in the EA group was significantly improved, and the relative protein expression levels of α-SMA, IL-1β, PI3K and Akt were obviously decreased (P<0.05), while the level of IL-4 was significantly increased (P<0.05). H.E. staining and Masson staining showed that the glomeruli of the mice in the model group were atrophied and sclerotic, the renal tubules were hypertrophied and disorganized, the inflammatory cell infiltration was obvious, and the collagen fibers of the renal interstitium were obviously increased, which was relatively milder in the EA group.

Conclusions: "Kidney-reinforcing and Govenor Vessel-regulating" EA can inhibit the over-expressions of IL-1β and α-SMA and increase the expression of IL-4 in aging renal tissue, which may contribute to its effects in delaying renal aging. Inhibiting the PI3K/Akt signaling may be one of the possible mechanisms of EA anti-renal fibrosis.