3.1. Renal injury was attenuated in Empa treated mice.
The Schematic diagram of the
experimental procedure was shown in Figure 1A. Remarkable increase of
body and kidney weight was detected in KK-AY group and these changes
were rescued partially in Empa treated mice (Figure 1B, C, E).
Meanwhile, the urinary NGAL
(ng/24h), and urinary NAG (U/24h), two markers of tubular injury
increased obviously in KK-AY group at the 10th week
though no significant change of
urinary
microalbumin (μg/24h) was found (Figure 1F, G, H). With the prolongation
of high-fat diet breeding, an obvious increase of 24h
urinary microalbumin (ug/24h) was
detected in KK-AY group at 16th week, and these trends
were reversed in the Empa group (Figure 1 F, G, H).The HE stains of
kidney showed obvious tubular vacuolation and dilatation in KK-AY group,
and the Empa alleviate these alterations partially (Figure 1D).
3.2. The apoptosis in
KK-Ay mice kidney were alleviated in Empa treated mice.
Apoptosis is a form of programmed cell death which has been proved to be
connected to DKD. In present
study, the number of TUNEL positive cells increased dramatically in
KK-AY group, and this trend was reversed significantly in Empa group
(Fig. 2B). Proteins related to cellular apoptosis were also measured by
Western Blotting. We found that in KK-AY group, the expression
of pro-apoptotic proteins such as
BAX, Cleaved-CASPSE 3 increased significantly, whereas the
anti-apoptotic protein BCL-2 reduced obviously, all these changes were
reversed in Empa group (Fig. 2A, D). Cytochrome c (CYT), which is
released from mitochondria to cytoplasm in the process of apoptosis
plays a critical role in the activating of CASPASE. Here we found that
the CYT in mitochondria decreased obviously in the KK-AY group and, in
the Empa group the mitochondrial CYT recovered (Fig. 2C, D). These above
findings suggest that the diabetic environment result in increased
apoptosis in kidney and these
changes were partially reversed in Empa group.