Review article
Antidiabitic effects of Effects of Cassia fistula
Introduction
Cassia fistula, also known as the golden shower tree, is a flowering plant in the family Fabaceae. The species is native to the Indian subcontinent and adjacent regions of Southeast Asia. It ranges from southern Pakistan eastward throughout India to Myanmar and Thailand and south to Sri Lanka. This beautiful tree, also known as Amaltas, is usually medium in size and has dark green compound leaves that are large in size. The flowers of Cassia Fistula are bright yellow in, whereas are shiny dark brown in colour and are usually cylindrical in shape. The wood is hard, durable and heavy. It is used for making cabinets, inlay work, temple drums, fence posts, agricultural implements and also in construction of houses, bridges etc. The pulp from the fruit pods is used to flavour tobacco. The flowers are used to decorate hair. All parts of the tree are used in traditional medicine and also in Ayurvedic medicine.
1.1 Taxonomic classification
Kingdom – Plantae
Subkingdom – Tracheobinota
Super Division – Spermatophyta
Division – Mangoliophyta
Class – Magnoliopsida
Sub Class – Rosidae
Order – Fabales
Family – Fabacae
Genus – Cassia
Species – fistula
1.2 Vernacular names
Bengali- Bundaralati, Sonalu, Sondal
English- Indian Laburnum, Golden Shower.
Guajarati- Garmala
Hindi- Amultus
Tamil – Shrakkonnai, Konai
Sanskrit- Nripadruma
Oriya- Sunaari
Punjabi- Amaltaas
Urdu – Amaltaas
1.3 Geographical distribution
Cassia fistula is present in mixed as well as deciduous monsoon forests of India, stretching upto 1300m height in outer Himalaya. Even in Maharashtra, it grows as a scattered tree throughout the Deccan and Konkan . The plant is cultivated as an ornamental throughout India.
1.4 Morphology of C.fistula
The golden shower tree is a medium-sized tree, growing to 10–20 m (33–66 ft) tall with fast growth. The leaves are deciduous, 15–60 cm (5.9–23.6 in) long, and pinnate with three to eight pairs of leaflets, each leaflet 7–21 cm (2.8–8.3 in) long and 4–9 cm (1.6–3.5 in) broad. The flowersare produced in pendulous racemes 20–40 cm (7.9–15.7 in) long, each flower 4–7 cm (1.6–2.8 in) diameter with five yellow petals of equal size and shape. The fruit is a legume, 30–60 cm (12–24 in) long and 1.5–2.5 centimetres (0.59–0.98 in) broad, with a pungent odor and containing several seeds. The tree has strong and very durable wood, and has been used to construct "Ahala Kanuwa", a place at Adams Peak, Sri Lanka, which is made of Cassia fistula heartwood.
1.5 Uses of Cassia fistula
The wood is hard, durable and heavy. It is used for making cabinets, inlay work, temple drums, fence posts, agricultural implements and also in construction of houses, bridges etc. The pulp from the fruit pods is used to flavour tobacco. The flowers are used to decorate hair. All parts of the tree are used in traditional medicine and also in Ayurvedic medicine. Moreover The fruit is low in sodium.100 grams of fresh fruit provides 100% of the daily Vitamin K requirement.100 grams of dried fruit provides 800 mg calcium which is almost 100% of the daily need. It is a good source of the minerals iron and manganese. The concentration of these minerals is much higher than is present in apples, pears, oranges, peaches or apricots on a weight to weight basis.
.2. Photochemical components of Cassia fistula
Anthraquinone glycosides, rhein , sennosides A & B, its glucoside, aloin, butyric acid, formic acid, ethyl ester, oxalic acid are present inside the pulp of the pod. Pectin and tannin presence has also been marked. Seeds contain galactomannan free sugars and free amino acids; flowers contain rhein and a bianthraquinone glycoside, fistulin. From leaves we get free rhein, its glycosides- sennosides A & B. The pulp also contains sugar, gum, tannic matter, albuminous starch and other important components. In leaves and flowers anthraquinone, tannin, oxyanthraquinone, rhein and volatile oils are present. Root bark contains tannins as well as phlobaphenes and oxyanthraquinone substances. The bark contains two flavonol glycosides. Experiment performed in vegetative and reproductive organs of C. fistula taken from Mauritius and harvested at different stages, showed that among the vegetative organs, both young and old leaves showed the highest total phenolic, flavonoid and proanthocyanidin contents.
3. Cassia fistula-“a disease killer"
In Ayurvedic medicine, the golden shower tree is known as aragvadha, meaning "disease killer". The various parts of the tree like the bark, root, flowers, leaves, fruit pulp are used medicinally and have several health benefits. The tree has anti diabetic, anti fertility, anti tumor, hepato protective, and cholesterol lowering, astringent, febrifugal, and purgative, anti inflammatory, antioxidant, antibacterial, antiviral, analgesic, tonic, anti dysenteric properties. It also alleviates symptoms and pain of arthritis, gout, nervous system diseases, eczema, ringworm, leucoderma, leprosy etc. Is benefits in constipation where there is drying of the fluids in the intestine due to the high pitta on the intestine. It has a gentle laxative action and can be used in children and elderly alike. Amaltas subsides gas, flatulence, acidity. It reduces colic pain. It eases the discomfort of piles, stops bleeding from different parts of the body and benefits in heart disease. Given below are some therapeutic effects of Cassia fistula
Hepatoprotective activity
Hepatotoxicity is a condition when liver is damaged, causing this critical organ to under function, or to function irregularly. The liver is the largest organ in the body and has many important functions to perform. One of its most important task is to filter out toxic substances from the body, including alcohol, carbon tetra chloride (CCl4), different medications like paracetamol, and other antidiabetic drugs, different medications, such as chemotherapy drugs, antibiotics. Experimental studies tell that Cassia fistula’s alcoholic root extract can be protective against CCl4 induced hepatotoxicity.CCl4 and Olive Oil (in ratio 1:1; 2ml/kg) was injected in adult Wistar albino rat’s colony. The rats were divided into 6 groups for 7 days: I-control, II-CCl4 treated , III- standard silymarine treated, IV-ethanol extract(100 mg), V- ethanol extract (200mg).The levels of the marker enzymes (SGOT, SGPT, ALP) of liver functions were initially elevated, were decreasing in a progressive manner. There was an increase in the body weight in. The Serum total protein and the Serum albumin also reached normal level. Alcoholic extract 200mg/kg treated rats showed more comparable results with a standard drug Silymarin.
Antidiabetic activity
Diabetes is a widespread systemic disease affecting a major proportion of the worldwide population. Diabetes mellitus is a group of metabolic diseases. The pathogenic processes involved in the development of diabetes range from autoimmune destruction of the pancreatic cells with subsequent insulin deficiency to abnormalities that result in resistance to insulin action. The basis of the abnormalities in protein, fat, carbohydrate metabolism in diabetes is because of the poor action of insulin on the target tissues. Inadequate insulin secretion and/or diminished tissue responses to insulin at one or more points in the complex pathways of hormone action results in the poor insulin action. The main symptoms of diabetes are: feeling very thirsty, urinating more frequently than usual, particularly at night, feeling very tired, weight loss and loss of muscle bulk, blurred vision, slow healing of cuts and grazes. There are two major categories of diabetes- type 1diabetes which is caused due to absolute deficiency of insulin secretion and type 2 diabetes, which is caused due to resistance to insulin action and also due to an insufficient compensatory insulin secretory response. Deficiency of insulin secretion and defects in insulin action often coexist in the same patient, and it is still unclear which abnormality, if either alone or their combination, is the main cause of hyperglycemia. Recent studies indicate that out of six percent of the population that is affected with diabetes, 90 percent is type 2 diabetes. The therapeutic options available currently, for instance oral hypoglycemics and insulin, are not always satisfactory in avoiding the later stage diabetes complications. Also, the chronic nature of this disease and its associated complications require regular treatment and this incurs a huge financial expenditure on the family and the healthcare system. Hence, there is a need for natural drugs that are effective, affordable, inexpensive, and safe to consume. Cassia fistula Linnaeus is one such plant that is reported to be effective as an antidiabetic agent.
In a recent experimental study based on the comparative evaluation of antidiabetic effects of different parts of Cassia fistula, the hypoglycemic effect of the methanolic and aqueous extracts of entire parts of Cassia fistula were investigated, in normoglycemic as well as streptozotocin-nictotinamide induced type 2 diabetic rats. Oral glucose tolerance test, acute toxicity study, and glucose uptake in isolated rat hemidiaphragm were performed in normal rats. In Sprague Dawley rats, diabetes was induced intraperitoneally by the administration of streptozotocin-nictotinamide (50, 110 mg/kg b.w., resp.). The different extracts of Cassia fistula were administered(for 21 days) to the diabetic rats at 250 mg/kg and 500 mg/kg doses. Biochemical parameters like insulin, blood glucose, glycosylated hemoglobin, serum marker enzymes and lipid profile were determined. The methanolic extract of leaves and the bark were show more effective in causing hypoglycemia in normoglycemic rats. After oral administration of the bark and leaf methanolic extracts, the diabetic rats that showed increased levels of glycosylated hemoglobin, reduced levels of plasma insulin, were significantly reverted to near normal. Glucose uptake studies in isolated rat hemidiaphragm showed enhanced peripheral utilization of glucose. Finally, the data obtained from this study clearly indicated that the methanolic extract of the leaves and bark at 500 mgkg−1 dose showed significant antilipidemic and antihyperglycemic activity than at 250 mgkg−1 dose in the streptozotocin-nictotinamide induced diabetic rats. The extracts also showed improvement in parameters- insulin profile and glycosylated hemoglobin as well as in the regeneration of pancreatic beta cells and so might be of value in treatment of diabetes. Therefore, further investigation is required to identify the exact phytoconstituent(s) of Cassia fistula , that are responsible for its antidiabetic effect.
Anti ulcer effect
Methanolic extract of Cassia species seed extract exhibits antiulcer effect which was evaluated using pylorus ligation and indomethacin induced ulcers in wistar albino rats. Various biochemical parameters including gastric volume, free and total acidity were estimated. The study showed that a significant reduction of ulcer index as well as gastric acid output in extract treated animals was observed with respect to control animals. The extract exhibited 75% protection in pylorus ligation model and 70.31% protection in indomethacin induced ulcers. (1) (2)
ANTIOXIDANT ACTIVITY
There has been increase in interest in the pharmacological properties of this plant as an antioxidant recently. Antioxidant is a molecule which slows down or prevents the oxidation of the other molecule. Naturally occurring antioxidants scavenge free radicals from our body. Free radical is a chemical species which has an unpaired electron. They are very unstable and can damage the cells and tissues if the amount of these free radicals exceed in the body. Damage mediated by free radicals results in the disruption of membrane fluidity, protein denaturation, lipid peroxidation, oxidative DNA, alteration of platelet functions and finally leads to various problems, which have generally been considered to be linked with many chronic health problems such as cancers, inflammation, aging and atherosclerosis[1]. Superoxide anion, hydrogen peroxide, peroxyl radicals, reactive hydroxyl are common reactive oxygen species.
The biological membranes is made up of lipids and proteins. If the amount of protein in the cell membrane increases the number of functions of membrane also increases. Reactive oxygen species can easily initiate the lipids causing damage of the cell membrane constituent i.e. phospholipids, lipoproteins by propagating a reaction cycle[2]. Antioxidants can inhibit lipid oxidation thus inhibiting this chain reaction, and also scavenge free radicals. It has been reported that phenolic compounds might be responsible for the antioxidant activity of plants. Flavonoids are a group of polyphenolic compounds with known properties which include free radical scavenging, inhibition of hydrolytic oxidative enzymes and anti-inflammatory action[2].
There are many methods which are employed to analyse the antioxidant activity of Cassia fistula such as DPPH radical scavenging activity, Ferric Reducing Antioxidant Potential Assay(FRAP), Hydroxyl Radical Scavenging Activity Assay, Reducing Power Assay. Md. Irshad et al performed an experiment in which antioxidant potential of various extract of Cassia fistula was seen using all the methods. Methanolic extracts of pulp(MEP), Methanolic extracts of seed(MES), Hexane extracts of pulp(HES), and Hexane extracts of seed(HES) were prepared. Methanolic extract of cassia fistula had higher amount of phenolic and flavanoid content and hexane extract had the lowest amount. It was concluded that the phenolic content of extracts was greatly related to antioxidant capacity of Cassia fistula. Ascorbic was taken as a control as it showed the highest antioxidant activity in the study. DPPH Radical Scavenging is the most accurate, and widely used method to determine antioxidant activity. DPPH is the most stable free radical. The order of DPPH scavenging was found to be in the order of MEP>MES>HEP>HES[3].
Nayan R.Bhalodia et al did Evaluation of in vitro Antioxidant activity of Flowers of Cassia fistula Linn. The study was carried out on Hydroalcoholic extract of shade dried flowers. Phenolic content was determined by Folin Ciacalteu reagent and Hydroalcoholic extract was analysed by DPPH assay for measuring radical scavenging activity and was compared to ascorbic acid. Ferric Reducing power was also determined using Oyaizu method to measure reducing power. the hydroalcoholic extract of contained a good amount of total phenols and tannins also flavonoids type components,which plays a major role in controlling antioxidants. It was concluded that hydroalcoholic extract showed antioxidant activity by inhibiting DPPH and hydroxyl radical, total phenol content and reducing power activities[4].
P. Suresh Kumar et al evaluated Antioxidant activity in some selected Indian medicinal plants. Cassia fistula was one of them. In this study lipid peroxidation inhibition activity, total alkaloid content and total flavanoid content were determined in shade dried powdered leaves. The experiments were performed thrice. Alkaloids and Flavonoids show antioxidant activity which has considerable health care effects on human. Alkaloids are involved in inhibition of peroxidation. According to the study the high content of these compounds can explain high lipid peroxidation inhibition activity. The lipid peroxidation inhibition was third highest in Cassia fistula after C. auriculata followed by A. Amara[2].
Sangetha SANTURAN NEHRU et al screened Free radical scavenging activity of Cassia spectabilis and Cassia fistula. Leaves, Flowers, Stem and pod were dried at room temperature and powdered. Methanol extracts of all parts of plant were performed and free radical scavenging activity was measured quantitatively with DPPH scavenging assay as comparable with known recognized antioxidant BHT. Scavenging activity of all extracts were great especially in the case of Cassia fistula with highest in flowers and then pod. The scavenging effect of leaves and stem were also noticeably good. The scavenging effect of C. spectabilis was comparatively lower than C. fistula[5].
In conclusion, the screening of antioxidant activity performed on selected plants from Penang, Malaysia which traditionally used as herbs [8-9] shows that they are endowed with potentially exploitable free radical scavenging activity. Finally, future investigations will concern in-depth analyses (both in terms of chemistry and antioxidant activity) of the isolation and identification of main components and the in vivo evaluation of their pharmacology. Cassia fistula can be used as easily accessible source of natural antioxidants and as a possible food supplement or in pharmaceutical industry.
Wound healing capacity of Cassia fistula
Experimental studies suggests that Cassia fistula can be used in healing wounds after an experiment was performed on albino rat model to see the wound healing capacity of Cassia fistula .The alcohol extract of leaves of C. fistula was used for analysis of antibacterial effect against Staphylococcus aureus ATCC 29213 and Pseudomonas aeruginosa ATCC 27853.Formulated ointment was applied on the infected wound. It was observed that theC. fistula treated rats showed, better wound closure, improved tissue regeneration at the wound site.