Hyaluronic Acid Oligosaccharides Improve Myocardial Function Reconstruction and Angiogenesis against Myocardial Infarction by Regulation of Macrophages

Figure 1. Schematic illustration of preparation, post-MI treatment and LV repair mechanism of o-HA.

Figure 2. Synthesis and characterization of o-HA. A) Synthesis of o-HA. B, C, D) GPC, 1H NMR, and FTIR spectrum of o-HA.

Figure 3. Histological analysis of hearts harvested 28 d after MI. A) infarcted region assessed based on TTC staining of heart sections, the infarcted field was white. B) photograph of hearts causing MI after treated by four groups. (n=8). C) Images from four-treated groups showing morphological changes with H&E staining of heart paraffin sections. D) Images from four-treated groups showing myocardial fibrosis with MT staining of heart paraffin sections. E) % LV infarct area of different groups. F) The relative thickness of LV (%) in different groups.

Figure 4. showed cardiac function measured by echocardiography at 28 d after surgery. A) Representative echocardiograph from the various groups. B) LV internal diameters of diastole (LVIDd) and systole (LVIDs) were measured at the view of short axis from M mode. LV ejection fraction (LVEF) and fractional shortening (LVFS) was calculated using VisualSonic analysis software (n=6 animals/group). ***P< 0.001 vs NS.

Figure 5. Release of cTn I and CK-MB after MI. A) Values of cTn I in blood at various time point were displayed. cTn I released with early rising, reaching peak, and decreasing over several days. The o-HA group with smaller cTn I peak. B) Concentration of CK-MB in post-MI mice after being treated for 28 d.

Figure 6. IHC analysis of expression of A) TUNEL, B) CD31 and C) Ki-67 in heart sections of different group after treated for 28 d.

Figure 7. FCM analysis in infarcted area microenvironment at 24 h, 72 h, 7 d, 14 d and 21 d. A, C) M2 type macrophages distribution after treatment. B, D) neutrophils inhibition.

Figure 8. Migration and invasion of peritoneal macrophages by o-HA. A) and D) promotion of o-HA on macrophages in “Wound healing” analysis. B) and E) Transwell migration of macrophages triggered by o-HA compared with NS and h-HA. C) and F) invasion of macrophage induced by o-HA in Transwell assay.

Figure 9. Polarization of peritoneal macrophages with o-HA in vitro. A, F) NS. B, F) h-HA, 500 μg/mL. C, F) o-HA, 250 μg/mL. D, F) o-HA, 500 μg/mL. E) VEGF expression by western blots assay of M2 macrophage.

Figure 10. (A) Heatmap depiction of differentially expressed genes among o-HA, h-HA and NS groups treated macrophages from two independent experiments. (B, C) KEGG analysis of all differentially function and signaling pathways enrichment between o-HA and NS treated macrophages. (D) Heatmap depiction of differentially expressed genes in signaling pathways among o-HA, h-HA and NS groups treated macrophages from two independent experiments.