Preclinical Rodent Models of Arthritis and Acute Inflammation Indicate Immunomodulatory and Anti-Inflammatory Properties of Juglans regia Extracts

Abstract

Juglans regia has been used to treat inflammatory and arthritic disorders in traditional medicine. The present study aimed to investigate the antiarthritic and anti-inflammatory potential of ethanolic leaves extract of J. regia. Arthritis was induced in rodents with Freund’s complete adjuvant. J. regia treatment was started on 8th day of arthritis induction and sustained for 20 days. Acute inflammatory models were developed using carrageenan, histamine, serotonin, and dextran. Qualitative and GC-MS analyses were also performed. Arthritis was determined using an arthritis scoring index and histopathological examination of ankle joints. RT-PCR was performed to determine the expression of pro-inflammatory markers (TNF-α, NF-κB, IL-6, IL-1β, and COX-2) and anti-inflammatory IL-4. PGE2 levels were evaluated using an ELISA. Blood and biochemical parameters were also determined. Paw edema was measured using a digital plethysmometer. Treatment with extracts inhibited arthritic development and attenuated paw edema along with all histopathological parameters. The expression levels of pro-inflammatory cytokines and COX-2 were downregulated, while IL-4 was upregulated. PGE2 levels were also reduced in extract-treated groups. Blood and biochemical parameters were nearly normalized in the treatment groups. Both extracts significantly inhibited carrageenan, histamine, serotonin, and dextran-induced paw edema. Qualitative phytochemical screening and GC-MS analysis confirmed that extracts possessed potential medicinal compounds. In conclusion, ethanol and n-hexane extracts of J. regia leaves have immunomodulatory and anti-inflammatory effects that ameliorate experimentally induced arthritis and edema. The inhibition of autacoids may also be one of the mechanisms inducing the immunomodulatory effect.

Anti-Arthritic and Immunomodulatory Potential of Methanolic, n-Hexane, and Ethyl Acetate Fractions of Bark of Acacia modesta on Complete Freund’s Adjuvant-Induced Arthritis in Rats

“…The samples were processed with chloroform, isopropyl alcohol, and 75% ethanol for RNA extraction. After extraction, the RNA samples were processed to determine their quantity and purity using a nanodrop spectrophotometer [ 38 ]. Each sample containing 1000 ng RNA was reverse transcribed according to the kit manufacturer’s protocol (Thermo Scientific, Waltham, MA, USA) to synthesize cDNA [ 39 ].…”

Chrysin Is Immunomodulatory and Anti-Inflammatory against Complete Freund’s Adjuvant-Induced Arthritis in a Pre-Clinical Rodent Model

“…According to the World Health Organization (WHO), 80% of the world's population relies on traditional medicine through the use of plants to treat diseases, and this dependence is increasing day by day due to their cost-effectiveness, safety, and high quality compared with synthetic drugs [21]. Different medicinal plants and their constituents possess many pharmacological properties such as analgesic, anti-pyretic, anti-inflammatory, anti-arthritic, anti-microbial, anti-proliferative, anti-cancer, anti-hemolytic, anti-depressant, and anti-oxidant properties [22].…”

Mechanistic Evaluation of Antiarthritic Effects of Citronellol in CFA-Induced Arthritic Rats

“…The relative expression was determined using the 2 –ΔΔ CT method. The primers were designed using previously published data …”

“…The primers were designed using previously published data. 23 2.6. Assessment of Arthritic Progression.…”