Inhibitory Effect of Aqueous Ectract of Saffron (Crocus Sativus L.) on Adjuvant-induced Arthritis in Wistar Rat
Summary
Inhibitory Effect of Aqueous Ectract of Saffron (Crocus Sativus L.) on Adjuvant-induced Arthritis in Wistar Rat : Crocus sativus L. (Saffron) is a plant of the iris family (Iridaceae). Saffron flower contains various chemical constituents. Saffron has been long used in folk medicine for treating some disease conditions. Its stigma contains crocin, anthocyanin, carotene and lycopene which are known to have pharmacological effects on various illnesses. In this study we have investigated the effects of saffron stigma aqueous extract (SAE) in complete Freund’s adjuvant (CFA) induced arthritis rat model. So, Male Wistar rats weighed 120-150 g were used.
Animals were injected with 100 µl of CFA (100 mg/ml) into the right tibiotarsal joint. After complete establishment of arthritis on day 14, animals were placed in 6 groups (five animals in each); groups II, III, IV and V AIA rats were injected intraperitoneally with 100, 200, 400 and 800 mg/kg saffron aqueous extract (SAE), respectively. Groups I and VI of AIA rats were injected intraperitoneally with an equal amount of normal saline and dexamethasone at a dose of 2 mg/kg body weight as a standard reference, respectively. Saffron, normal saline and dexamethasone injections were repeated four more times every other day (days 2, 4, 6 and 8). Measurement of the paws footpad and tibiotarsal joints diameters on the injected and not-injected paws were performed every three days.
An arthritis index was assigned to each animal based on footpad paw diameter, ankle joint diameter and hyperalgesia. Our results show that saffron aqueous extract at 400 mg/ml has the best effect on reducing the footpad and tibiotarsal joint diameters, arthritis indexes and limitations of movement in CFA induced arthritis rats compared to non treated group. However this reduction is not as significant as dexamethasone treated group. It seems that aqueous extract of saffron stigma can alleviate the inflammatory condition of CFA induced arthritis. We showed the effect of saffron aqueous extract on improving disease condition in adjuvant-induced arthritis in rats.
Introduction; Inhibitory Effect of Aqueous Ectract of Saffron
Rheumatoid arthritis (RA) is a chronic systemic inflammatory autoimmune disease and is associated with disability and premature mortality (1, 2). Although many medicines are prescribed for the treatment of RA, they are known to produce various side effects including gastrointestinal disorders, immunodeficiency and humoral disturbances. So, there is still a need to seek therapeutic agents with lower side effects that can be used for long-term administration (3).
Saffron is produced from dried stigmas of Crocus sativus L. which is a bulbous perennial of the iris family (Iridaceae) and is principally grown in Iran. Crocus sativus L. is used for its goldencolored, pungent stigmas, which are dried and used to flavor and color foods as well as a dye (4-7). Study on chemical composition of saffron has identified approximately 40–50 constituents including carbohydrates, minerals, mucilage, vitamins and pigments, flavonoids, amino acids, proteins, starch and gums (8-10).
Saffron has several biological activities and is considered as an anodyne, anticonvulsant, antidepressant, respiratory decongestant, antispasmodic, diaphoretic, emmenagogue, expectorant, and sedative. Saffron has also been used in the treatment of scarlet fever, smallpox, colds, asthma, eye and heart diseases, tumor and cancer (11-19). In a recent study, aqueous extract of C.
sativus stigma (saffron) was used in treatment of acute inflammation in a xylene-induced ear edema in mice and also in chronic inflammation in formaldehyde induced arthritis in hind paw of rats. Their results showed that aqueous extract of saffron stigma which dominantly contains alkaloids and saponins has an antinociceptive effect, as well as activity on acute and chronic inflammation (20). Adjuvant arthritis in rats is a widely used experimental model of chronic inflammation with manifestations resembling clinical disorders such as RA and ankylosing spondylitis (21). In this study, we assessed the effects of saffron aqueous extract on adjuvant-induced arthritis (AIA) in Wistar rats as a model for rheumatoid arthritis.
Materials and methods; Animals ” Inhibitory Effect of Aqueous Ectract of Saffron”
Male Wistar strain (150–180 g) rats were used in this study. The animals were housed in standard laboratory conditions with 12±1 h day and night rhythm throughout the experimental period. The animals were housed in large spacious polypropylene cages and they were fed according to standard protocols. The rats were kept in our animal house for at least one week before the experiment.
Plant material
Saffron was purchased from Novin Saffron Co. (Mashhad, Iran).