Combination of carvacrol with methotrexate suppresses Complete Freund's Adjuvant induced synovial inflammation with reduced hepatotoxicity in rats.

The present study evaluated the therapeutic benefit of the combination of carvacrol, an isoprenoid having potential anti-inflammatory action, with methotrexate in suppressing Complete Freund's Adjuvant induced arthritis and attenuating methotrexate induced hepatic damage. Arthritis was induced in rats with Complete Freund's Adjuvant. Animals received methotrexate (2mg/kg) intraperitonealy once a week for 5 weeks alone and along with carvacrol orally (50 and 100mg/kg) respectively from the 10th to the 42nd day. Control and carvacrol alone group were also studied. Paw volume, hypernociception, and erythrocyte sedimentation rate were evaluated as arthritic markers. Hepatic marker enzymes in serum; myeloperoxidase, protein oxidation, and oxidative measures were determined in the liver homogenate. Liver histological assessments were also carried out. Methotrexate significantly controlled arthritis; however, liver damage was evident due to oxidative stress and rise in myeloperoxidase levels. Carvacrol suppressed the hyperalgesic response, significantly alleviated arthritis and reduced damage to the hepatocytes owing to a decline in the levels of myeloperoxidase and oxidative markers. High dose of the combination reduced the levels of glutamic oxaloacetic transaminase, glutamic pyruvic transaminase and alkaline phosphatase by 24.74%, 30.2% and 28.14% compared with methotrexate treatment. Histological assessment also revealed that carvacrol minimizes methotrexate induced liver toxicity. In combination, carvacrol promoted the anti-arthritic action of methotrexate, reduced neutrophils infiltration and peroxidative damage to the liver. Therefore, carvacrol can serve as a useful adjuvant and promote the safe use of methotrexate in the management of arthritis.

Curcumin and piperine abrogate lipid and protein oxidation induced by D-galactose in rat brain.

Cerebellar atrophy during ageing can produce neurobehavioural changes characterized by cognitive and motor impairment. Chronic exposure to D-galactose, a reducing sugar can accelerate ageing by producing an unprecedented rise in oxidative load. This can enhance neuronal damage by promoting the oxidation of protein and lipids. We perceived that the simultaneous administration of piperine and curcumin, two powerful antioxidants can exert neuroprotective effect by inhibiting damage caused by the chronic exposure to D-galactose. Young Wistar rats treated with D-galactose (150 mg/kg, s.c.) were simultaneously treated with piperine alone, curcumin separately; and in combination for a period of 56 days by the oral route. A vehicle control, D-galactose alone and naturally aged control were also evaluated. Cognitive changes, motor impairment, protein carbonyls, protein thiols, advanced oxidation protein products, 4 hydroxynonenol and nitric oxide levels were determined in the brain homogenate. In order to ascertain the impact of cerebellum on motor performance, histopathological changes in the cerebellum were also established. Results obtained from our studies reflect a marked improvement in memory, sensorimotor performance, reduced oxidative and nitrosative burden on simultaneous treatment with piperine and curcumin. Furthermore, alterations produced in the Purkinje cells were minimized on treatment with the combination. Our studies demonstrated the influence of protein and lipid oxidation products on behavioural changes in D-galactose induced ageing model. Incorporation of these antioxidants might reduce the risk of developing neurodegenerative disorders, an important counterpart of advancing age.