Kidney tissues morphologies were detected in processed IR spectroscopic maps.

<p>IR spectra of control group (black), model group (red), and EGCG3”Me-treated group (green) normalized to the amide I band. Arrows indicate the relevant phospholipid peaks of the C–H stretch band at 2922 cm^–1, the C = O stretch at 1740 cm^–1, and the phosphate bands at 1080 and 1240 cm^–1 in the model and decreased by EGCG3”Me, which indicated that EGCG3”Me decreasing lipid and other cell content.</p

EGCG3”Me decrease RAGE, IL6, p27 protein levels in diabetic kidney.

<p>(A), Western blot analysis of RAGE, IL6, and p27 expression was carried out in diabetic kidney compared with control; (B), Immunochemistry analysis of RAGE (brown) in diabetic kidney, which indicating that EGCG3”Me inhibited the development of diabetic nephropathy and other complications of diabetes.</p

Effects of EGCG3”Me extracts on the blood glucose of diabetic mice.

<p>^## represents the statistical significance vs. control group; **represents the statistical significance vs. diabetes model, n = 6 to 8.</p

Immunoblotanalysis with anti-4-HNE antibodies to detect carbonylated proteins in the insoluble proteins SDS fraction (insoluble proteins) in the kidneys.

<p>EGCG3”Me treatment could greatly decrease the 4-HNE proteins content in the diabetic kidneys.</p

Chemical structures of EGCG and EGCG3”Me isolated from tea leaves.

<p>EGCG has flavan-3-ol structure with A and B rings and a D-galloyl group. EGCG3”Me contains a methyl ether group at the 3″ position of the D ring.</p

Inhibitory effect of EGCG3”Me on the formation of carbonylated proteins in the serum.

<p>^##represents statistical significance vs. control group; **represents statistical significance vs. diabetes model, n = 6–8.</p

EGCG3”Me treatment could sharply decrease the formation of antiparallel β-sheets in diabtetic kidneys.

<p>FTIR spectra of amide I (normalization and appropriate baselines from 1700 cm^–1 to 1600 cm^–1) show that alloxan-induced diabetic model correspond to a high β-sheet content (1675 cm^–1 to 1695 cm⁻¹); EGCG3”Me increased α-helix content (1660 cm^–1 and 1650 cm^–1)(a), and the different secondary structure bands using Gaussian curve fitting program Origin 8.0 ((B), control; (C), model; (D), EGCG3”Me treatment).</p

FTIR analysis of lipofuscin (LF) β-sheet-rich amyloidogenesis structure.

<p>(A) The FTIR spectra of the protein products in different treatment groups. (B-D) The peaks from a Gaussian curve fitting of the FTIR spectra of the amide I band (normalization processing) of protein products in different treatment groups. Sparse shading is β-sheet structure (1625 to 1640 cm^-1), and dense shading is antiparallel β-sheet/aggregated strands structure (1675 to 1695 cm^-1). LF and LF+EGCG represent LF and EGCG (300 μM) treated LF groups after 96 h of incubation, respectively.</p

(-)-Epigallocatechin gallate (EGCG) prevented β-sheet-rich amyloidogenesis of lipofuscin (LF).

<p>(A) Effect of EGCG on LF formation as measured by emission of LF-like fluorescence intensity at 460 nm in MDA-modified HSA artificial LF (1 mg/mL) reaction system. (B) Effect of EGCG on LF β-sheet-rich structure formation by measuring Thioflavin T (ThT) fluorescence emission at 485 nm. (C) Analysis of sample aggregation reactions by transmission electron microscopy (TEM) in different groups after 96 h of incubation. Scale bars represent 100 nm. Data are expressed as means ± SD, n = 3.</p

(-)-Epigallocatechin gallate (EGCG) inhibited the formation of lipofuscin (LF) β-rich amyloidogenesis structure.

<p>LF and LF+EGCG represent LF and EGCG (300 μM) treated LF groups after 96 h of incubation, respectively.</p