Protective effects of aqueous extract of Solanum nigrum Linn. leaves in rat models of oral mucositis

Abstract

Oral mucositis is one of the most debilitating side effects in patient undergoing chemotherapy or chemoradiotherapy. Leaves of the plant Solanum nigrum are used in folklore medicine to treat oral ulcers in India. However, no pharmacological investigation has been carried out till date. Aqueous extract of Solanum nigrum leaves (AESN) was prepared and subjected to various phytochemical screening. HPLC analysis of the ethyl acetate fraction was carried out. The aqueous extract (100 and 200 mg/kg) was further evaluated for its protective effect on two rat models: (a) busulfan plus infrared radiation (chemoradiotherapy) induced oral mucositis and (b) methotrexate (chemotherapy) induced oral mucositis. Various parameters including body weight change, food intake, and mortality were measured. AESN showed protective effect in both models of oral mucositis; however, the higher dose was more effective in chemotherapy induced oral mucositis. A reduction in oral mucositis score (P < 0.05) was observed in the treatment groups. Significant (P < 0.05) improvement in food intake was also observed in AESN treated groups. Aqueous extract of Solanum nigrum leaves has protective effect on chemotherapy and chemoradiotherapy induced oral mucositis in rats.

Figure 1

HPLC analysis of ethyl acetate fraction of Solanum nigrum Linn. The HPLC used a 4.6 mm × 250 mm, 5 µm Merck C₁₈ reversed-phase column. The chromatogram was recorded at 295 nm (PDA Multi 2).

Figure 2

Body weight changes in busulfan and radiation induced oral mucositis. Body weight change in each group was recorded from day 1 to day 15. All values are expressed as mean ± SEM of 6 animals. ^a P < 0.05 versus normal control, ^b P < 0.05 versus mucositis control.

Figure 3

Average food intake in busulfan and radiation induced oral mucositis. 15 g of food was provided for each animal of five groups till the end of study period. All values are expressed as mean ± SEM of 6 animals. ^a P < 0.05 versus normal control, ^b P < 0.05 versus mucositis control.

Figure 4

Oral mucositis score in busulfan and radiation induced oral mucositis. Oral mucositis score was measured on a scale of 0 to 5. Scores were analyzed using Kruskal-Wallis test followed by Dunn's multiple comparison tests. All values are expressed as mean ± SEM of 6 animals. ^a P < 0.05 versus normal control, ^b P < 0.05 versus mucositis control.

Figure 5

Mortality rate in busulfan and radiation induced oral mucositis. 0% mortality was observed in normal control and L-glutamate groups. However, 100% mortality was seen in mucositis control group on 13th day. Mortality in both the treatment groups was found to be 17% at the end of study period.

Figure 6

Histology of tongue section of different groups after busulfan/infrared irradiation. (a) Normal control, (b) mucositis control, (c) L-glutamine, (d) AESN 100 mg/kg, and (e) AESN 200 mg/kg. Magnification 40x.

Figure 7

Body weight change in methotrexate induced oral mucositis. Body weight change in each group was recorded from day 1 to day 15. All values are expressed as mean ± SEM of 6 animals. ^a P < 0.05 versus normal control, ^b P < 0.05 versus mucositis control.

Figure 8

Average food intake in methotrexate induced oral mucositis. 15 g of food was provided for each animal of five groups till the end of study period. All values are expressed as mean ± SEM of 6 animals. ^a P < 0.05 versus normal control, ^b P < 0.05 versus mucositis control.

Figure 9

Methotrexate induced oral mucositis score. Oral mucositis score was measured on a scale of 0 to 3. Scores were analyzed using Kruskal-Wallis test followed by Dunn's multiple comparison tests. All values are expressed as mean ± SEM of 6 animals. ^a P < 0.05 versus normal control, ^b P < 0.05 versus mucositis control.

Figure 10

Mortality rate in methotrexate induced oral mucositis. 0% mortality was observed in normal control and L-glutamate groups, whereas in mucositis control group 100% mortality was observed on 8th day. In AESN (100 mg/kg and 200 mg/kg) the mortality rate was found to be 33% and 0%, respectively, at the end of study period.