Figure 1

The effects of SH and CDP (alone or in combination) on basic state of T2DM mice A, state of appearance; B, food intake during nine-week drug treatment; C, body weight before and after drug administration for 9 weeks; D, FBG du-ring nine-week drug treatment (△△P < 0.01, vs. Ctrl mice; ▲▲P < 0.01, vs. Mod mice); E-H, levels of plasma TG, TC, ALT and AST in the end of nine-week drug treatment. Data are shown as ${\bar x}$±s (n=10). * P < 0.05; * * P < 0.01;-, the dosage of corresponding drug is 0 mg; NS, not significant. SH, sarpogrelate hydrochloride; CDP, carbidopa; T2DM, type 2 diabetes mellitus; FBG, fasting blood glucose; TG, triglyceride; TC, total cholesterol; ALT, alanine transaminase; AST, aspartate transaminase. Grouping: Ctrl, control group; Mod, T2DM model group treated without SH and CDP; SH, T2DM model group treated with SH alone [100 mg/(kg·d)]; CDP, T2DM model group treated with CDP alone [100 mg/(kg·d)]; SH+CDP, T2DM model group treated with SH [66.7 mg/(kg·d)] and CDP [33.3 mg/(kg·d)] in combination."

Figure 2

The relevance of 5-HT2AR, 5-HT synthesis, and 5-HT degradation with liver oxidative stress and hepatic steatosis of T2DM mice A, expression of 5-HT2AR, Tph1 and AADC in liver of T2DM mice (immunohistochemistry staining ×400); B, Western blot analysis of 5-HT2AR, Tph1 and AADC in liver of Ctrl and T2DM mice; C, levels of 5-HT; D, expression of MAO-A; E-I, levels of H2O2, MDA, SOD, GSH and TG in the liver tissue of each group. J, inflammatory cell infiltration (arrow pointing), lipid droplets and ballooning degeneration of hepatocytes in the liver of T2DM model and amelioration in each drug treatment group (HE staining ×400). Data are shown as ${\bar x}$±s (n=10). * P < 0.05; * * P < 0.01;-, the dosage of corresponding drug is 0 mg; NS, not significant. 5-HT, 5-hydroxytryptamine; 5-HT2AR, 5-HT 2A receptor; Tph1, tryptophan hydroxylase-1; AADC, aromatic amino acid decarboxylase; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; MAO-A, monoamine oxidase A; H2O2, hydrogen peroxide; MDA, malondialdehyde; SOD, superoxide dismutase; GSH, glutathione. Other abbreviations as in Figure 1."

Figure 3

The effects of inhibition of peripheral 5-HT2AR and 5-HT synthesis on hepatic inflammation and fibrosis in T2DM mice A, expression of p-IκBα, IκBα, p-NF-κB p65, NF-κB p65 and GAPDH; B-E, levels of TNF-α, IL-1β, TGF-β1 and ColⅣ; F, expression of TGF-β1, α-SMA, MMP-2 and ColⅠin the liver tissues; G, hepatic fibrosis in the portal area of liver (Masson staining ×400); H, hepatic fibrosis in the-parenchymal region of liver (Masson staining ×400). Data are shown as ${\bar x}$±s (n=10). * P < 0.05; * * P < 0.01;-, the dosage of corresponding drug is 0 mg. IκBα, inhibitor α of NF-κB; p-IκBα, phosphorylated IκBα; NF-κB, nuclear factor kappa B; p-NF-κB, phosphorylated NF-κB; TNF-α, tumor necrosis factor α; IL-1β, interleukin 1β; TGF-β1, transforming growth factor β1; Col Ⅳ, collagen Ⅳ; ColⅠ, collagenⅠ; α-SMA, α-smooth muscle actin; MMP-2, matrix metalloproteinase-2. Other abbreviations as in Figure 1 and 2."

Figure 4

The relevance of 5-HT2AR, 5-HT synthesis and 5-HT degradation with D-Glu-induced ROS production in LX-2 cells SH (5 μmol/L), CDP (5 μmol/L), CGL (10 μmol/L), and 33 mmol/L or 66 mmol/L D-Glu were used in experiment. LX-2 cells were treated for either 24 h and 48 h (A) or 48 h (B-G). A, B, expression of 5-HT2AR, Tph1, AADC, and GAPDH in the Ctrl cells and D-Glu-treated cells with different time or different concentration. C, 5-HT levels in the Ctrl cells and D-Glu-treated cells with (+) or without (-) SH, CDP or CGL treatment; D, expression of Tph1 and GAPDH in the Ctrl cells and D-Glu-treated cells with or without SH treatment; E, expression of MAO-A and GAPDH in the Ctrl cells and D-Glu-treated cells with or without SH or CDP treatment; F, H2O2 levels in the Ctrl cells, SH, CDP or CGL-treated cells, and D-Glu-treated cells with or without SH, CDP, SH+CDP or CGL treatment; G, ROS distribution in the Ctrl cells and D-Glu-treated cells with or without SH, CDP, SH+CDP or CGL treatment (fluorescent probe staining ×630). Data are shown as ${\bar x}$±s (n=4). * * P < 0.01; NS, not significant.D-Glu, D-glucose; CGL, clorgyline. Other abbreviations as in Figure 1 and 2."

Figure 5

The relevance of 5-HT2AR and 5-HT degradation with the activation of both inflammatory signaling pathway and fibrosis induced by high glucose in LX-2 cells Except for the control (Ctrl), LX-2 cells treated with (+) or without (-) SH (5 μmol/L) or CGL (10 μmol/L) were exposed to D-Glu (33 mmol/L) or not for 48 h. A, expression of p-IκBα, IκBα, p-NF-κB p65, NF-κB p65 and GAPDH in cells; B, C, levels of TNF-α and IL-1β in medium; D, expression of α-SMA, TGF-β1, MMP-2 and ColⅠin cells; E, levels of Col Ⅳ in medium. Data are shown as ${\bar x}$±s (n=4). * P < 0.05; * * P < 0.01; NS, not significant. Abbreviations as in Figure 2-4."