Proteins derived from in vitro culture of the callus and roots of Calotropis procera ameliorate acute inflammation in the rat paw

Amelioration of complete Freund’s adjuvant-induced arthritis by Calotropis procera latex in rats

Background

Rheumatoid arthritis is the most common cause of disability, affecting 0.3–1% of the adult population worldwide. The latex of Calotropis procera possesses potent anti-inflammatory as well as analgesic properties. In light above facts, the present study was designed to evaluate anti-arthritic activity of Calotropis procera latex in complete Freund's adjuvant (CFA)-induced arthritis in Wistar albino rats. Complete Freund's adjuvant was injected into the left hind paw on day 0, and treatment of prednisolone and Calotropis procera latex was given from day 0 to 28. Various biochemical, hematological and functional parameters as well as radiological and histopathological changes of joint along with body weight and paw volume were measured.

Results

Calotropis procera treatment significantly lowered paw volume in CFA-induced arthritic rats. Significant improvement was observed in functional, biochemical and hematological parameters in Calotropis procera-treated rats. However, the body weight remained unaffected. Histological and radiographical examination of synovial joints in Calotropis procera-treated animals exhibited less synovial hyperplasia, infiltration and accumulation of inflammatory cell in synovial fluid, cartilage and bone erosion and joint space narrowing.

Conclusion

Calotropis procera latex possesses anti-arthritic activity, which is facilitated by modulation in the level of inflammatory mediators and oxidative stress. The improvement in hematological as well as biochemical parameters might be reflected on functional, histopathological, radiological changes and thereby disease progression.

Evaluation of Anti-inflammatory Efficacy of RA-V: a Natural Cyclopeptide

Inflammation occurs in a cascade reaction to cause damage in the tissues. It involves increased expression of oxidants and cytokines in the injured tissues. Peptides are chosen for the development of alternate and more selective anti-inflammatory therapies. They are highly specific and significant due to their low molecular weight, simple structure, low antigenicity, and low toxicity. They are capable of easy absorption through different routes of administration and rapid clearance from the system. Plant-derived cyclic peptides have great therapeutic values. Peptides from Rubia cordifolia exhibit potent anti-inflammatory, anti-diabetic, anti-arthritic, and antioxidant properties. Cyclotides are small peptides isolated from plants with a cyclic backbone and disulfide bonds. The cyclic cystine knot structure of the cyclic peptide makes them resistant to chemical, enzymatic, and thermal conditions. They are isolated from Rubiaceae, Violaceae, and Cucurbitaceae plant families. The overall aim of this study is to evaluate the biological efficacy of the cyclopeptide, RA-V (deoxybouvardin) isolated from Rubia cordifolia.

Protective Effect of High Molecular Weight Protein Sub-fraction of Calotropis procera Latex in Monoarthritic Rats

Background:

Proteins present in the latex of Calotropis procera have been shown to produce anti-inflammatory effect and to afford protection in various disease models.

Objectives:

To determine the efficacy of high molecular weight protein sub-fraction (LP_PI) of latex of C. procera in ameliorating joint inflammation and hyperalgesia in a preclinical model of arthritis.

Materials and Methods:

Monoarthritis was induced in rats by intra-articular injection of Freund's complete adjuvant (FCA) and the effect of two doses of LP_PI (5 and 25 mg/kg) and diclofenac (5 mg/kg) was evaluated on joint swelling, stair climbing ability, motility, and dorsal flexion pain on day 3. The rats were sacrificed on day 3 to measure tissue levels of reduced glutathione (GSH) and thiobarbituric acid reactive substances (TBARS). Evaluation of joint histology was also made.

Results:

Intra-articular injection of FCA produced joint swelling and difficulty in stair climbing ability, motility, and pain on flexion of the joint as revealed by scores obtained for these functional parameters. LP_PI produced a dose-dependent decrease in joint swelling and improved joint functions. Arthritic rats also revealed altered oxidative homeostasis where joint tissue GSH levels were decreased and TBARS levels were increased as compared to normal rats. The levels of these oxidative stress markers were near normal in arthritic rats treated with LP_PI. Moreover, treatment with LP_PI also maintained the structural integrity of the joint. The protective effect of LP_PI was comparable to the standard anti-inflammatory drug, diclofenac.

Conclusion:

The findings of the present study show that LP_PI fraction comprising high molecular weight proteins could be used for the alleviation of arthritic symptoms.

SUMMARY

High molecular weight protein sub-fraction of latex of Calotropis procera (LP_PI) reduced joint swelling and hyperalgesia in arthritic rats

LP_PI produced a significant improvement in stair climbing ability and motility in arthritic rats

LP_PI normalized the levels of oxidative stress markers in the arthritic joints

Treatment with LP_PI reduced neutrophil influx and edema in the arthritic joints

Abbreviations used: FCA: Freund's complete adjuvant, GSH: Glutathione, TBARS: Thiobarbituric acid reactive substances, TBA: Thiobarbituric acid, MDA: Malondialdehyde, LP_PI: Latex protein fraction PI.