Evaluation of wound healing activity of oral administration of ethanolic extract of Michelia champaca in diabetic wistar rats Shenoy S*, Gowda A, Shanbhag T, Prabhu K,

Nelluri V

*Department of Pharmacology, Kasturba Medical College, Manipal, India

Background

Wound healing - impaired in patients with diabetes

mellitus. Michelia champaca - family Magnoliaceae.

Flowers used by traditional healers for

ulcers, skin disease and wounds

Objective

To assess the effect of oral administration of ethanolic

extract of flowers of Michelia champaca on

healing of incision and excision wounds in

diabetic wistar rats.

Methods

Approval from Institutional Animal Ethics Committee obtained

Ethanolic extract of flowers of Michelia champaca

(MC) was prepared

Suspension of the extract made by using CMC 0.5% (carboxymethylcellulose)

Wound models

Incision wound

Excision wound

Animals

Five groups in each model

Six rats in each group

Total adult albino rats, wistar strain = 60

Group Drug, route

Group I (non-diabetic control)

CMC 0.5%, oral

Group II (diabetic control )

CMC 0.5%, oral

Group III (diabetic test)

100 mg/kg of Michelia champaca extract, oral

Group IV (diabetic test)

200 mg/kg of Michelia champaca, extract, oral

Group V (diabetic test)

400 mg/kg of Michelia champaca , extract, oral

Induction of diabetes

Streptozotocin (STZ) solution :

intraperitoneally - 30mg/kg

- four groups of rats

Incision wound

Two 6 cm long paravertebral straight incisions - through

entire thickness of the skin on the back of the rats.

closed with intermittent sutures

Parameter assessed

10th postoperative day - breaking strength of the wound –

continuous constant waterflow technique of Lee

Excision wound model Parameters assessed

Rate of wound contraction (%) =

initial wound size – specific day wound size

initial wound sizex 100

Period of epithelization

wound created on day 7 after induction of diabetes

anesthesia - ketamine (80 mg/kg) i.p.

round seal of 2.5 cm diameter - on the dorsal interscapular region, 5 cm away from the ears

full thickness skin from demarcated area excised

→ wound - 400 mm2 & 2 mm depth

Duration of drug administration

from day 0 (day of wounding)

to day 21 or

till wound was completely healed,

whichever occurred earlier

Histopathology

10th postoperative day,

granulation tissue from wound area –

using a punch biopsy needle (5 mm), under

ketamine anesthesia

Statistical analysis

one-way ANOVA followed by

Tukey Post-hoc test

Results

Effect of Michelia champaca on breaking strength of incision wound

Groups Drugs Breaking strength (g)

( Mean ± SEM)

Group ICMC 0.5%, oral

(nondiabetic control) 256.56 ± 6.54

Group IICMC 0.5%, oral(diabetic control) 222.61 ± 4.62*

Group III100 mg/kg Michelia

champaca extract, oral 238.17 ± 5.56

Group IV200 mg/kg of Michelia champaca extract, oral 245.78 ± 6.79

Group V400 mg/kg of Michelia champaca extract, oral 270.50 ± 4.40**

*p < 0.05 vs nondiabetic control ; **p < 0.05 vs diabetic control

Effect of Michelia champaca on healing

of excision wound

Groups Drug Period of epithelization - days ( Mean ± SEM)

Group I CMC 0.5%, oral(nondiabetic control)

18.86 ± 0.82

Group II CMC 0.5%, oral(diabetic control)

22.16 ± 0.45 *

Group III 100 mg/kg of Michelia champaca extract, oral

21.67 ± 0.22

Group IV 200 mg/kg of Michelia champaca extract, oral

20.72 ± 0.34

Group V

400 mg/kg of Michelia champaca extract, oral

19.31 ± 0.37 **

*p < 0.05 vs nondiabetic control ;

**p < 0.05 vs diabetic control

Groups Wound contraction (%) (Mean ± SEM) / drugs Day 4 Day 8 Day 12 Day 16

I- CMC 0.5% 18.62±3.66 40.53±2.47 60.88±5.21 81.24±4.12

II-CMC 0.5% 15.62±1.72 28.26±5.27* 43.92±3.76* 64.1±4.04*

III-MC extract100 mg/kg

17.45±4.23 31.57±1.45 49.28±5.46 70.97±3.13

IV - MC extract 200 mg/kg

18.36±4.64 35.60±3.26 52.32±4.10 73.77±5.26

V- MC extract 400 mg/ kg

21.86±2.70 37.97±4.87 62.94±3.48** 82.42±3.58**

*p < 0.05 vs nondiabetic control ; **p < 0.05 vs diabetic control

(c)

(e)

Discussion

Diabetic wounds – reduced

cellular infiltration, formation of granulation tissue,

collagen synthesis, breaking strength

Michelia champaca –

promoted better organization of collagen, reepithelization,

increased wound contraction rate, breaking strength

Michelia champaca – has

tannins, triterpenoids

antioxidant properties

antimicrobial actions

Conclusion

Ethanolic extract of Michelia champaca on oral

administration has a beneficial influence on wound

healing in diabetic rats

.