Effect of Solanum melongena peel extract in the treatment of arsenic-induced Bowen’s disease
Abstract
The aim of this study was to see the effectiveness of Solanum melongena peel extract in the treatment of arsenic-induced Bowen’s disease. In total 8 patients of arsenic-induced Bowen’s disease were selected from the two arsenic-endemic areas. The peel extract containing ointment was provided to each patient and instructed him/her to apply twice daily on the site of the lesion for 12 weeks. The measurement of the lesion size as well as photograph were collected both before and at the end of the study. The mean (± SD) diameter of the lesion was 3.8 ± 1.9 cm which reduced to 2.5 ± 1.7 cm (reduction 34%). The result was statistically significant.
Introduction
Arsenicosis is a chronic medical condition caused by the ingestion of arsenic contaminated water (>50 ppb) for more than six months (Misbahuddin, 2015). The common skin manifestations are melanosis and keratosis (Caussy, 2005). Some patients also suffer from Bowen’s disease (Yu et al., 2001 and Lee et al., 2004). It is a squamous cell carcinoma in situ. Bowen’s disease may be due to arsenic or non-arsenic-induced.
The published results show the treatment options of non-arsenic-induced Bowen’s disease are cryotherapy, curettage with cautery, excision, 5-fluorouracil, radiotherapy, laser, photodynamic therapy, imiquimod, etc. Topical diclofenac and topical imiquimod and photodynamic therapy are also recommended (Neubert and Lehmann, 2008). None of the options has been claimed to be superior to the other. Each procedure has advantages and disadvantages. However, the recurrence rate is high. Acitretin was reported to treat the arsenic-induced Bowen’s disease (Yerebakan et al., 2002).
Skin cancer can be treated with several plants like Camelia sinensis (Kumari et al., 2017), Solanum melongena (Cham et al., 1991), Solanum nigrum (Al Sinani et al., 2016), Sylibum marianum (Tsai et al., 2015), Polygonum cuspidatum (Ali and Braun, 2014), Plumbago zeylanica (Checker et al., 2010), etc.
So, the present study was carried out to see whether S. melongena peel extract was effective in the treatment of arsenic-induced Bowen’s disease.
Materials and Methods
Arsenicosis is a chronic medical condition caused by the ingestion of arsenic contaminated water (>50 ppb) for more than six months (Misbahuddin, 2015). The common skin manifestations are melanosis and keratosis (Caussy, 2005). Some patients also suffer from Bowen’s disease (Yu et al., 2001 and Lee et al., 2004). It is a squamous cell carcinoma in situ. Bowen’s disease may be due to arsenic or non-arsenic-induced.
The published results show the treatment options of non-arsenic-induced Bowen’s disease are cryotherapy, curettage with cautery, excision, 5-fluorouracil, radiotherapy, laser, photodynamic therapy, imiquimod, etc. Topical diclofenac and topical imiquimod and photodynamic therapy are also recommended (Neubert and Lehmann, 2008). None of the options has been claimed to be superior to the other. Each procedure has advantages and disadvantages. However, the recurrence rate is high. Acitretin was reported to treat the arsenic-induced Bowen’s disease (Yerebakan et al., 2002).
Skin cancer can be treated with several plants like Camelia sinensis (Kumari et al., 2017), Solanum melongena (Cham et al., 1991), Solanum nigrum (Al Sinani et al., 2016), Sylibum marianum (Tsai et al., 2015), Polygonum cuspidatum (Ali and Braun, 2014), Plumbago zeylanica (Checker et al., 2010), etc.
So, the present study was carried out to see whether S. melongena peel extract was effective in the treatment of arsenic-induced Bowen’s disease.
Results
Fifty percent of the death nauplii were found in the artificial seawater containing 100 µg/mL of S. melongena extract (Table I).
Table I: Numbers of death nauplii at different concentration of S. melongena peel extract
| Concentration of the extract (µg/mL) | Percentage of death nauplii at the end of 24 hours |
|---|---|
| 0 | 10% |
| 0.1 | 90% |
| 1.0 | 70% |
| 10.0 | 60% |
| 100.0 | 50% |
The mean (± SD) age of the patients was 53.1 ± 6.6 years (Table II). The mean amount of arsenic in the tube-well water consumed by the patients was 677.3 ± 140.1 µg/L. The mean amount of arsenic in the nail sample was 28.3 ± 15.0 µg/g. The mean duration of exposure to arsenic-contaminated water was 20.9 ± 5.8 years. The mean duration of the appearance of the Bowen’ disease lesions was 8.8 ± 7.3 years.
Table II: Baseline characteristics of the patients
| Patients | |
|---|---|
| Age (years) | 53.1 ± 6.6 |
| Sex | |
| Male | 3 |
| Female | 5 |
| Number of smoker | |
| Smoker | 1 |
| Non-smoker | 7 |
| Tube-well water arsenic concentration (µg/L) | 677.3 ± 140.1 |
| Arsenic concentration in nail (µg/g) | 28.3 ± 15.0 |
| Arsenic exposure duration (years) | 20.9 ± 5.8 |
| Duration of appearance (year) | 8.8 ± 7.3 |
| Data are mean ± SD | |
The number of drop out patients was two due to loss to follow-up. The new lesions appeared on the chest of a patient of Bowen’s disease who was a smoker.
Measurement of the Bowen’s disease lesion size
The size (mean ± SD) of the lesions during the enrollment was 3.8 ± 1.9 cm which was reduced to 2.5 ± 1.7 cm after 12 weeks of the topical application of ointment and the total percentage of reduction was 34% (Table III). This change was statistically significant (p=0.0003). There was a reduction in the elevation of the lesions (Figure 1).
Table III: Measurement of Bowen’s disease lesion size
| Patient (#) | Size of the lesion size (cm) | p value | |
|---|---|---|---|
| Before study | After study | ||
| 1 | 4.5 | 2.7 | 0.0003 |
| 2 | 2 | 0.4 | |
| 3 | 2.5 | 1.5 | |
| 4 | 7.6 | 5.9 | |
| 5 | 2.2 | 1.5 | |
| 6 | 2.7 | 1.9 | |
| 7 | 5 | 3.1 | |
| 8 | 3.8 | 3.2 | |
| Mean ± SD | 3.8 ± 1.9 | 2.5 ± 1.7 | |
| Paired t-test was between before and after study to estimate the level of significance of difference | |||
Figure 1: Photographs show the effectiveness of the extract of three patients of Bowen’s disease. Left column represents before treatment and right column represents after treatment
During the first two weeks of topical application of ointment, the lesion became erythematous and subside after the next two weeks.
Discussion
The present study revealed the significant improvement effect in reducing the lesion of Bowen’s disease. The improvement of patient’s lesion was assessed by measuring lesion size. The size of the Bowen’s disease lesions was 2 to 7.6 cm in diameter. After topical application of S. melongena peel extract containing ointment for 12 weeks, the percentage of reduction was statistically significant.
This is the first study showing the effect of topical application of S. melongena peel extract in the treatment of arsenic-induced Bowen’s disease. Only 34% improvement was shown. The effect may be more if the a) higher concentration of the extract was used, b) modification of the ointment for better penetration of the extract through the skin, c) prolonged duration of action, and d) increased frequency of administration. However, in this study, the recurrence was not observed except one who was a smoker.
S.melongena is a vegetable. Its peel is violet in color which contains nasunin and chlorogenic acid. The nasunin is an anthocyanin (from the Greek anthos = flower and kyano = blue), 700 mg per 100 g and is responsible for the purple color of this vegetable. Both show antioxidant effect and can be used in aging, inflammation, cardiovascular disease, cancer (Gallo et al., 2014).
S.melongena fruit is rich in steroidal alkaloids, which were reported to possess anticancer activity against liver and lung cancer (Kuo et al., 2000; Liu et al., 2004). The methanol extract of the peel contains five steroidal compounds; three steroidal alkaloids: solasodine, solamargine and solasonine together with two steroidal glycosides: β-sitosterol-3-O-β-D-glucoside and poriferasterol-3-O-β-D-glucoside. These compounds exhibited moderate to potent activities against the tested human cancer cell lines colon cancer cell line (HCT116), larynx cancer cell line (HEP2), breast cancer cell line (MCF7), cervix cancer cell line (HELA) and liver cancer cell line (HEPG2) (Shabana et al., 2013).
The present study is similar to the findings of the topical application of low concentration (0.005%) of a standard mixture of solasodine glycosides to 29 squamous cell carcinoma (skin) patients (Cham et al., 1991). There was complete regression of lesions without recurrence. This component is more specific for the malignant cells than the normal cells and the new normal cells regrow at the place of the lesion.
The solasodine glycosides are cytotoxic substances present in the S. melongena peel extract and able to kill cancer cells. The plasma membrane of the susceptible cancer cells expresses specific endogenous endocytic lectins that bind to the sugar moiety of the solasodine glycosides and induces cell death by lysis of the targeted tumor cells. It is harmless for normal cells due to the absence of endogenous endocytic lectins.
A study explained the mode of action of solamargine as a potent cytotoxic activity against tumor cells by initiate a death process named oncosis. It also displays an unusual mode of action thus it avoids the common multidrug resistant mechanism (Sun et al., 2011).
Nasunin is an anthocyanin of the S. melongena peel extract showed biological abilities to prevent the production of free radicals, induces apoptosis, inhibits cell proliferation and angiogenesis.
One study was conducted in the two arsenic-induced Bowen’s disease patients treated with acitretin (1 mg/kg) daily (Yerebakan et al., 2002). The total cure was obtained in case of the first patient after 10 months but another patient discontinued the treatment after five months due to symptomatic adverse effects like hearing loss, insomnia and joint pain.
A patient with arsenicâ€induced keratoses and Bowen's disease responded well to acitretin (Watson and Creamer, 2004).
Acitretin is a retinoid analog (vitamin A). It works by inhibiting the excessive cell growth and keratinization. It, therefore, reduces the thickening of the skin, plaque formation and scaling. S. melongena peel extract containing solasodine glycosides which induced apoptosis of the cells by up-regulation of tumor necrosis factor and Fas receptor. Also decrease the Bcl2 expression concomitant increase protein level of Bax which collectively activation of the intrinsic and extrinsic pathway of apoptosis through caspase -8,-9 and -3.
Forty one patients of non-arsenic-induced Bowen’s disease were treated with topical 5-fluorouracil for 4-12 weeks (Sturm, 1979). The concentration of 5-fluorouracil was 1% for the face area and 2.5-3% for other areas of the body. After treatment (three patients recur), 8% recurrence occurred which was retreated with the same medication. But the main limitation was the prolonged treatment period with the recurrent application of medicine and skin irritation with burning sensation and discoloration of the affected site.
5-Fluorouracil is a pyrimidine analog that irreversibly binds within a cell to thymidylate synthetase. This prevents the incorporation of uracil into nuclear RNA, which destroys abnormal cancer cells. It acts non-specifically both in cancer and normal cells.
Another study conducted with 16 patients of Bowen’s disease (not arsenic-induced) applied the topical 5% imiquimod cream (Mackenzie-Wood et al., 2001). In that study, showed clinical improvement in ten patients after 16 weeks of treatment and the rest of six patients discontinued the treatment due to irritation, skin rash and erythema of the local skin.
Imiquimod cream (5%) is an immunomodulator which stimulates the local cytokines thus regression and normalization of the normal keratinocytes (Tyring et al., 1998).
The study of comparison of photodynamic therapy with topical 5-fluorouracil in Bowen’s disease showed that 88% initial complete clearance rate with photodynamic therapy and 67% complete cured with 5-fluorouracil (Salim et al., 2003). Follow-up at 12 months, photodynamic therapy group recurrences were two and six in 5-fluorouracil group. No adverse reaction was observed in photodynamic therapy-treated patients. On the other hand, three patients develop widespread dermatitis, one patient develops ulceration with painful erosions during the medication period. The photodynamic therapy is costly and may need more than one session.
Another study with methyl aminolevulinate with photodynamic therapy (MAL-PDT) when compared with placebo-PDT or cryotherapy (Bath-Hextall et al., 2013) demonstrate statistically significant but the cryotherapy shows recurrence at one year with no statistically significant difference in clearance rate when compared with the 5-fluorouracil in Bowen’s disease. Cryotherapy is painful and the skin may be uncomfortable for a few weeks.
Conclusion
S.melongena extract containing ointment has significant beneficial effects in the treatment of Bowen’s disease.
Ethical Issue
The protocol was approved by the Institutional Review Board of Bangabandhu Sheikh Mujib Medical University (Reg. No. BSMMU/ 2017/ 3322). This work was registered on the clinical trial.gov (Registration number was NCT 03122561).
All the participants were informed about the objective, potential hazards, benefits and outcome of this study. All the information was explained in an easy and local language (Bengali). Informed consent was taken in a consent-form with either participant’s thumb impression or signature.
All the participants were monitored and looked after carefully. Whether any complication arises during this treatment period, they had under careful observations and the researcher agreed to organize the symptomatic treatment.
Acknowledgement
We are grateful to the villagers of Monsurabad Union of Bhanga Upazilla of Faridpur District and Sirajdikhan Upazilla of Munshiganj District, for participating actively in this study. We are also grateful to Upazilla health and family planning officer of Bhanga Dr. Md. Abdullah and Dr. Dulal Hossain of Sirajdikhan Upazilla Health Complex. Also thanks to the community health care provider Mr. Md. Safique and health inspector Mr. Md. Habibur Rahman.
References
Al Sinani SS, Eltayeb EA, Coomber BL, Adham SA. Solamargine triggers cellular necrosis selectively in different types of human melanoma cancer cells through extrinsic lysosomal mitochondrial death pathway. Cancer Cell Int. 2016; 16: 11.
Ali I, Braun DP. Resveratrol enhances mitomycin C-mediated suppression of human colorectal cancer cell proliferation by up-regulation of p21WAF1/CIP1. Anticancer Res. 2014; 34: 5439-46.
Bath-Hextall FJ, Martin RN, Wilkinson D, Lonardi-Bee J. Interventions of cutaneous Bowen’s disease. Cochrane Database of Systemic Reviews. 2013, p 6.
Bhuiyan HA, Tshering K, Misbahuddin M. Estimation of arsenic in nail using silver diethyldithiocarbamate method. Bangladesh J Pharmacol. 2015; 10: 513-17.
Block LH. Ointments. In: Remington: The science and practice of pharmacy. Gennaro AR (ed). 20th ed. Vol 1. 2000, pp 845-46.
Caussy D. A field guide for detection, management and surveillance of arsenicosis cases. New Delhi, WHO Regional Office for South-East Asia, 2005.
Cham BE, Daunture B, Evans RA. Topical treatment of malignant and premalignant skin lesion by very low concentrations of standard mixture (BEC) of solasodine glycosides. Cancer Lett. 1991; 59: 183-92.
Checker R, Sharma D, Sandur SK, Subrahmanyam G, Krishnan S, Poduval TB, Sainis KB. Plumbagin inhibits proliferative and inflammatory responses of T cells independent of ROS generation but by modulating intracellular thiols. J Cell Biochem. 2010; 110: 1082-93.
Gallo M, Naviglio D, Ferrara L. Nasunin, an antioxidant anthocyanin from eggplant peels, as natural dye to avoid food allergies and intolerances. Eur Sci J. 2014; 10.
Kumari M, Pattnaik B, Rajan SY, Shrikant S, Surendra SU. EGCG-A Promis anticancer. Phytochemistry 2017; 3: 8-10.
Kuo KW, Hsu SH, Li YP, Lin WL, Liu LF, Chang LC, Lin CC, Lin CN, Sheu HM. Anticancer activity evaluation of the solanum glycoalkaloid solamargine: Triggering apoptosis in human hepatoma cells. Biochem Pharmacol. 2000; 60: 1865-73.
Lee CH, Yu CL, Liao WT. Effects and integrations of low doses of arsenic and UVB on keratinocyte apoptosis. Chem Res Toxicol. 2004; 17: 1199-205.
Liu LF, Liang CH, Shiu LY, Lin WL, Lin CC, Kuo KW. Action of solamargine on human lung cancer cells: Enhancement of the susceptibility of cancer cells to TNFs. FEBS Lett. 2004; 577: 67-74.
Mackenzie-Wood A, Kossard S, Launey J, Wilkinson B, Owens ML. Imiquimod 5% cream in the treatment of Bowen’s disease. J Am Acad Dermatol. 2001; 44: 462-70.
Misbahuddin M. Arsenicosis: A global issue. New York, Science Publishing Group, 2015, pp 1-204.
Niño-Medina G, UrÃas-Orona V, Muy-Rangel MD, Heredia JB. Structure and content of phenolics in eggplant (Solanum melongena): A review. South Afr J Bot. 2017; 111: 161-69.
Neubert T, Lehmann P. Bowen’s disease: A review of newer treatment options. Ther Clin Risk Manag. 2008; 4: 1085-95.
Salim A, Leman J, Mccoll JH, Chapman R, Morton CA. Therapeutics randomized comparison of photodynamic therapy with topical 5-flurouracil in Bowen’s Disease. Br J Dermatol. 2003; 148: 539-43.
Sarah Q, Anny F, Misbahuddin M. Brine shrimp lethality assay. Bangladesh J Pharmacol. 2017; 12.
Shabana MM, Salama MM, Ezzat SM, Ismail LR. In vitro and in vivo anticancer activity of the fruit peels of Solanum melongena L. against hepatocellular carcinoma. J Carcinog Mutagen. 2013; 4: 149-54.
Sturm HM. Bowen’s disease and 5-fluorouracil. J Am Acad Dermatol. 1979; 1: 513-22.
Sun L, Zoha Y, Yuan H, Li X, Cheng A, Lou H. Solamargine, a steroidal alkaloid glycoside, induces oncosis in human K562 leukemia and squamous cell carcinoma KB cells. Cancer Chemother Pharmacol. 2011; 67: 813-21.
Tsai CC, Chuang TW, Chen LJ, Niu HS, Chung KM, Cheng JT, Lin KC. Increase in apoptosis by combination of metformin with silibinin in human colorectal cancer cells. World J Gastroenterol. 2015; 21: 4169-77.
Tyring SK, Arany II, Stanley MA, Stoler MH, Tomai MA, Miller RL, Owens ML, Smith MH. Mechanism of action of imiquimod 5% cream in the treatment of anogenital warts. Primary Care Update for OB/ GYNS. 1998; 5: 151-52.
Watson K, Creamer D. Arsenicâ€induced keratoses and Bowen's disease. Clin Exper Dermatol. 2004; 29: 46-48.
Yerebakan O, Ermis O, Yilmaz E, Basaran E. Treatment of arsenical keratosis and Bowen’s disease with acitretin. Int J Dermatol. 2002; 41: 84-87.
Yu HS, Lee CH, Jee SH, Ho CK, Guo YL. Environmental and occupational skin diseases in Taiwan. J Dermatol. 2001; 28: 628-31.
