Effect of apple phenols on anxiety/depression in a rat model of acute exacerbation of chronic obstructive pulmonary disease

Figure 1 Weight changes of rats in each group. Data are presented as mean ± SD (n = 12 per group). ^aP < 0.01 vs control group, ^bP < 0.05 vs model group, ^dP < 0.05 vs low-dose apple polyphenols, ^eP < 0.05 vs middle-dose apple polyphenols. Control: Normal control group; Model: Acute exacerbation of chronic obstructive pulmonary disease model group induced by cigarette smoke and lipopolysaccharide; AP-L: Low-dose apple polyphenols; AP-M: Middle-dose apple polyphenols; AP-H: High-dose apple polyphenols; AP-H + mcc950: High-dose apple polyphenols + NOD-like receptor protein 3 inhibitor.

Figure 2 Compare lung function indicators of different groups of rats. A: Peak expiratory flow; B: Peak inspiratory flow; C: Forced expiratory volume in 0.3 seconds to forced vital capacity ratio. ^aP < 0.01 vs control group, ^bP < 0.05 vs model group, ^cP < 0.01 vs model group, ^dP < 0.05 vs low-dose apple polyphenols (AP), ^eP < 0.05 vs middle-dose AP,^fP < 0.05 vs high-dose AP. PEF: Peak expiratory flow; PIF: Peak inspiratory flow; AP-L: Low-dose apple polyphenols; AP-M: Middle-dose apple polyphenols; AP-H: High-dose apple polyphenols; AP-H + mcc950: High-dose apple polyphenols + NOD-like receptor protein 3 inhibitor.

Figure 3 Contrast the pathological damage of lung tissue in different groups of rats. Hematoxylin and eosin staining, original magnification (× 200). The red arrow: Alveolar atrophy and alveolar wall thickening; the black arrow: Inflammatory cell infiltration. Control: Normal control group; Model: Acute exacerbation of chronic obstructive pulmonary disease model group induced by cigarette smoke and lipopolysaccharide; AP-L: Low-dose apple polyphenols; AP-M: Middle-dose apple polyphenols; AP-H: High-dose apple polyphenols; AP-H + mcc950: High-dose apple polyphenols + NOD-like receptor protein 3 inhibitor.

Figure 4 Comparison of the expression of inflammatory factors in serum, lung tissue, and frontal lobe tissue homogenate of rats in different groups. A-D: Inflammatory factors in serum; E-H: Inflammatory factors in lung tissue; I-L: Inflammatory factors in prefrontal lobe tissue of the brain. ^aP < 0.01 vs control group, ^bP < 0.05 vs model group, ^cP < 0.01 vs model group, ^dP < 0.05 vs low-dose apple polyphenols (AP), ^eP < 0.05 vs middle-dose AP,^fP < 0.05 vs high-dose AP. AP-L: Low-dose apple polyphenols; AP-M: Middle-dose apple polyphenols; AP-H: High-dose apple polyphenols; AP-H + mcc950: High-dose apple polyphenols + NOD-like receptor protein 3 inhibitor; TNF: Tumor necrosis factor; IL: Interleukin.

Figure 5 Comparison of the expression of oxidative stress (malondialdehyde and lactate dehydrogenase) levels in serum, lung tissue, and frontal lobe tissue homogenate of rats in different groups. A and B: Oxidative stress in serum; C and D: Oxidative stress in lung tissue; E and F: Oxidative stress in prefrontal lobe tissue of the brain. ^aP < 0.01 vs control group, ^cP < 0.01 vs model group, ^dP < 0.05 vs low-dose apple polyphenols (AP), ^eP < 0.05 vs middle-dose AP,^fP < 0.05 vs high-dose AP. AP-L: Low-dose apple polyphenols; AP-M: Middle-dose apple polyphenols; AP-H: High-dose apple polyphenols; AP-H + mcc950: High-dose apple polyphenols + NOD-like receptor protein 3 inhibitor; MDA: Malondialdehyde; LDH: Lactate dehydrogenase.

Figure 6 Comparison the levels of depression and anxiety in different groups of rats. A: Sucrose preference rate; B: The total distance; C: Number of entries to the central area; D: Duration of stay in the central area. ^aP < 0.01 vs control group, ^cP < 0.01 vs model group, ^dP < 0.05 vs low-dose apple polyphenols (AP), ^eP < 0.05 vs middle-dose AP,^fP < 0.05 vs high-dose AP. AP-L: Low-dose apple polyphenols; AP-M: Middle-dose apple polyphenols; AP-H: High-dose apple polyphenols; AP-H + mcc950: High-dose apple polyphenols + NOD-like receptor protein 3 inhibitor.

Figure 7 Comparison the expression of NOD-like receptor protein 3 protein in lung tissues of rats in different groups. NLPR3: NOD-like receptor protein 3; GAPDH: Glyceraldehyde-3-phosphate dehydrogenase; AP-L: Low-dose apple polyphenols; AP-M: Middle-dose apple polyphenols; AP-H: High-dose apple polyphenols; AP-H + mcc950: High-dose apple polyphenols + NOD-like receptor protein 3 inhibitor.