Figure 1.
MMRKO protects against aortic constriction-induced cardiac hypertrophy.
(A) Ventricular weight to body weight ratio (VW/BW) of littermate control (LC) and myeloid specific MR knockout (MMRKO) mice with or without abdominal aortic constriction (AAC). (B) Representative H&E staining of cross sections of left ventricle samples. Scale bar: 50 µm. (C) Quantification of caridiomyocyte (CM) areas based on the measurements of CM size on H&E stained sections. The results were normalized to those of sham-operated LC group. (D) MMRKO reverses AAC-induced fetal gene program in left ventricles. ANP, Natriuretic peptide A; BNP, Natriuretic peptide B; bMHC, Cardiac myosin heavy chain beta; PLBN, Phospholamban; SERCA 2, Sarcoplasmic reticulum calcium ATPase 2. The expression levels were measured using qRT-PCR. GAPDH was used as an internal control. n = 4–7.
Figure 2.
MMRKO improves aortic constriction-induced cardiac fibrosis.
(A) and (B) Representative picrosirius red staining of heart sections showing perivascular and interstitial fibrosis respectively. Scale bar: 50 µm. (C) MMRKO attenuates up-regulation of fibrotic genes induced by AAC in left ventricles. CTGF, Connective tissue growth factor precursor; TGFb1, Transforming growth factor-beta 1; TGFb2, Transforming growth factor-beta 2. The expression levels were measured using qRT-PCR. GAPDH was used as an internal control. n = 4–7.
Figure 3.
Effects of MMRKO on expression of genes related to oxidative stress and cardiac metabolism.
(A) MMRKO decreases expression of genes important in generating reactive oxygen species. P40, p40phox; p47, p47phox; NOX2, NADPH oxidase 2; NOX4, NADPH oxidase 4. (B) MMRKO increases expression of manganese superoxide dismutase (MnSOD). (C) (D) (E) and (F) MMRKO upregulates expression of genes involved in cardiac metabolism. PPARa, peroxisome proliferator-activated receptor alpha; PGC-1a, peroxisome proliferator-activated receptor gamma coactivator 1-alpha; Acox1, acyl-Coenzyme A oxidase 1; Acadm, acyl-Coenzyme A dehydrogenase, medium chain; Acadvl, acyl-Coenzyme A dehydrogenase, very long chain; Sdhb, succinate dehydrogenase complex, subunit B, iron sulfur (Ip); Cox4i1, cytochrome c oxidase subunit IV isoform 1; Atp5j, ATP synthase, H+ transporting, mitochondrial F0 complex, subunit F; ATGL, adipose triglyceride lipase; OXPHOX, oxidative phosphorylation. The expression levels were measured using qRT-PCR. GAPDH was used as an internal control. n = 4–7.
Figure 4.
MMRKO reduces aortic constriction-induced cardiac inflammation.
(A) Representative immunofluorescence assay of cross sections of heart samples. Mac2 antibody was used to detect macrophages. Scale bar: 100 µm. (B) Quantification of macrophages stained by Mac2. (C) MMRKO decreases expression of macrophage marker genes in left ventricles. F4/80 (Emr1), EGF-like module containing, mucin-like, hormone receptor-like sequence 1. (D) MMRKO decreases expression of inflammatory genes in left ventricles. TNFa, tumor necrosis factor alpha; MIP-1b (Ccl4), chemokine (C-C motif) ligand 4; Cox2 (Ptgs2), prostaglandin-endoperoxide 2; MCP-1 (Ccl2), chemokine (C-C motif) ligand 2; IL-6, interleukin 6. The expression levels were measured using qRT-PCR. GAPDH was used as an internal control. n = 4–7.
Figure 5.
MMRKO improves aortic constriction-induced aortic fibrosis.
(A) Representative picrosirius red staining of aortic sections showing vascular fibrosis. Scale bar: 100 µm. (B) Quantification of fibrotic area stained by picrosirius red. (C) MMRKO attenuates up-regulation of fibrotic genes induced by AAC in aortas. CTGF, Connective tissue growth factor precursor. The expression levels were measured using qRT-PCR. 18 s was used as an internal control. n = 3–5.
Figure 6.
MMRKO mildly improves aortic constriction-induced aortic inflammation.
(A) Effects of MMRKO on expression of inflammatory genes. (B) MMRKO decreases expression of macrophage marker gene CD68 in aortas. The expression levels were measured using qRT-PCR. 18 s was used as an internal control. n = 3–5. (C) Representative immunofluorescence assay of aortas. Scale bar: 100 µm. (D) Quantification of macrophages stained by Mac2.