Characterization of Rubia cordifolia L. root extract and its evaluation of cardioprotective effect in Wistar rat model

Abstract

Objectives: Rubia cordifolia L. (RC) is a well-known and highly valuable medicinal plant in the Ayurvedic system. The present study involves evaluating antioxidant and cardioprotective property of RC root extract.

Materials and methods: The characterization of RC root extract was carried out using standard phytochemical and biochemical analysis. The functional groups were analyzed by Fourier transform infrared (FTIR) spectroscopy and phytotherapeutic compounds were identified using high-resolution mass spectrometry (HR-MS). Cardioprotective activity of RC root extract was investigated against cyclophosphamide (CP; 100 mg/kg, i.p)-induced cardiotoxicity in male albino Wistar rats. RC (100, 200, and 400 mg/kg, p.o) or silymarin (100 mg/kg, p.o) was administered immediately after CP on the 1^st day and the next consecutive 10 days. Biochemical and histopathological analysis was performed to observe the cardioprotective effects of RC root extract.

Results: Phytochemical analysis revealed the presence of secondary metabolites that include alkaloids, flavonoids, saponins, and anthraquinones in RC root extract. FTIR analysis revealed the presence of several functional groups. Based on HR-MS analysis, eight major phytotherapeutic compounds were identified in methanol root extract of RC. Biochemical analysis in CP-induced rat model administered with RC extract revealed significantly enhanced levels of antioxidant markers such as superoxide dismutase, catalase, and glutathione S-transferase. Histopathological study showed that the rat model treated with the root extract had reduced the cardiac injury.

Conclusion: Our results have shown that the RC extract contains various antioxidant compounds with cardioprotective effect. Treatment with RC root extract could significantly protect CP-induced rats from cardiac tissue injury by restoring the antioxidant markers.

Keywords: Antioxidants; Fourier transform infrared; Rubia cordifolia L.; cardioprotection; cyclophosphamide; high-resolution mass spectrometry.

Figure 1

Fourier transform infrared spectrum of methanolic root extract of Rubia cordifolia

Figure 2

Mass spectrum of isolated compounds from methanolic root extract of Rubia cordifolia

Figure 3

Effect of Rubia cordifolia on tissue superoxide dismutase (a), catalase (b), glutathione S-transferase (c), and lipid peroxidation (d) levels in cyclophosphamide-induced cardiotoxicity in rats. The data are expressed as the means ± standard error mean of six rats per group and analyzed using one-way analysis of variance followed by Student's paired t-test. *P < 0.05, **P < 0.01 when compared to cyclophosphamide-induced group. Note: Rubia cordifolia, cyclophosphamide

Figure 4

Effect of Rubia cordifolia on lipid peroxidation in cyclophosphamide-induced cardiotoxicity in rats. The data are expressed as the means ± standard error mean of six rats per group and analyzed using one-way analysis of variance followed by Student's paired t-test. *P < 0.05, **P < 0.01 when compared to cyclophosphamide-induced group. Note: Rubia cordifolia, cyclophosphamide

Figure 5

Histopathological evaluation of heart tissue in (a) Normal (H and E, 200×); (b) Cyclophosphamide 100 mg/kg treated (H and E, 200×); (c) Cyclophosphamide + Rubia cordifolia 100 mg/kg treated (H and E, 100×); (d) Cyclophosphamide + Rubia cordifolia 200 mg/kg treated (H and E, 100×); (e) Cyclophosphamide + Rubia cordifolia 400 mg/kg treated (H and E, 100×); (f) Cyclophosphamide + silymarin 100 mg/kg treated rats (H and E, 400×)