Immunomodulatory activity of mefenamic acid in mice models of cell-mediated and humoral immunity

Gaafar AR, Nafidi HA, Bourhia M. Mechanistic Evaluation of Antiarthritic Effects of Citronellol in CFA-Induced Arthritic Rats

Rheumatoid arthritis (RA) is an autoimmune disease characterized by systemic inflammation, joint tissue damage, pain, and synovitis. It leads to deformity of joints, disability, and even premature death. Markers of inflammation are highly expressed in synovium fluid and serum of arthritic patients and play an important role in the pathophysiology of RA. These transcription factors promote the fabrication of type I interferons and inflammatory cytokines. In RA, degradation of synovial cartilage and bone results from stimulation of proinflammatory cytokines. Citronellol (Ct), a monoterpene alcohol, is found in citrus fruits and essential oils of many aromatic plants. It possesses numerous pharmacological properties such as antioxidant activity and potential antinociceptive and anti-inflammatory effects. Keeping in view the significant anti-inflammatory role of Ct, a trial of 28 days was conducted. Ct was administered orally at three different doses (25, 50, and 100) mg/kg in Freund's adjuvant-induced arthritic rats, and the results were compared with piroxicam, chosen as the standard drug. The antiarthritic activity of the compound was evaluated through measurements of arthritic scoring and plethysmometry before and after treatment. The blood biochemical and hematological parameters and histopathological analyses were performed. Additionally, qPCR was conducted to analyze the mRNA expression levels of TNF-α, IL-1β, NF-κB, MMP3, IL-6, and IL-4 in the blood. ELISA was performed to evaluate the levels of PGE2. The results demonstrated that Ct showed significant results at all doses, but the highest dose proved to be most significant in terms of decreasing arthritic scoring and paw edema, indicating the antiarthritic potential of Ct. Furthermore, the compound was found to downregulate all the proinflammatory cytokines (TNF-α, IL-1β, NF-κB, MMP3, and IL-6) and upregulate the anti-inflammatory cytokine (IL-4). The levels of PGE2 were also reduced which further supported the antiarthritic effects of Ct and validated it as a potential antiarthritic candidate.

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

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.

Effect of Abelmoschus ficulneus (L.) Wight & Arn. on immunomodulation: in vivo experimental animal models

Background

Abelmoschus ficulneus (L.) Wight & Arn. (Malvaceae) commonly known as herb in the Ayurveda, Indian traditional medicine system. Herb is reported as a Rasayana that has the potential to produce immunomodulatory effects. In the present study, the immunomodulatory effect of aqueous (AEAF) and ethanolic (EEAF) leaves extract of A. ficulneus (L.) Wight & Arn. in different experimental animal models were evaluated.

Results

Acute oral toxicity shows that both extracts have wide range of safety as per OECD 420 guidelines. Quantitative and qualitative analysis was evaluated by performing preliminary phytochemical screening, thin layer chromatography and high-performance thin layer chromatography developed for simultaneous quantification of flavonoids (quercetin) in both the extracts. Oral administration of A. ficulneus L. extracts showed a significant increase in the primary and secondary humoral antibody responses against cyclophosamide (100 mg/kg) induced immunosuppression, by significantly increasing (p < 0.05) the hemagglutinating antibody titre at dose of 200 mg/kg/p.o. and also significantly (p < 0.05) potentiated delayed type hypersensitivity reaction induced by sheep red blood cells. There was a significant (p < 0.05) increase in the phagocytic index, percentage neutrophil adhesion and significantly prevented the mortality induced by bovine Pasteurella multocida in mice when compared with control group. Result findings shows that both the extracts have ability to inhibit immunosuppression induced by cyclophosamide.

Conclusion

Study finding shows that AEAF and EEAF (at dose 200 mg/kg) extracts exerts immunostimulatory effects on specific and nonspecific immune system thus chemical constituents of herbal extracts may have applications as an effective immunotherapeutic agent and its potential application in the treatment of immune-related diseases.

Analgesia for Sheep in Commercial Production: Where to Next?

Simple Summary

Increasing societal and customer pressure to provide animals with ‘a life worth living’ continues to apply pressure on industry to alleviate pain associated with husbandry practices, injury and illness. Although a number of analgesic solutions are now available for sheep, providing some amelioration of the acute pain responses, this review has highlighted a number of potential areas for further research.

Abstract

Increasing societal and customer pressure to provide animals with ‘a life worth living’ continues to apply pressure on livestock production industries to alleviate pain associated with husbandry practices, injury and illness. Over the past 15–20 years, there has been considerable research effort to understand and develop mitigation strategies for painful husbandry procedures in sheep, leading to the successful launch of analgesic approaches specific to sheep in a number of countries. However, even with multi-modal approaches to analgesia, using both local anaesthetic and non-steroidal anti-inflammatory drugs (NSAID), pain is not obliterated, and the challenge of pain mitigation and phasing out of painful husbandry practices remains. It is timely to review and reflect on progress to date in order to strategically focus on the most important challenges, and the avenues which offer the greatest potential to be incorporated into industry practice in a process of continuous improvement. A structured, systematic literature search was carried out, incorporating peer-reviewed scientific literature in the period 2000–2019. An enormous volume of research is underway, testament to the fact that we have not solved the pain and analgesia challenge for any species, including our own. This review has highlighted a number of potential areas for further research.

Mefenamic acid-loaded solid SMEDDS: an innovative aspect for dose reduction and improved pharmacodynamic profile

AIM

The current investigation is focused on solid self-microemulsifying drug-delivery systems (S-SMEDDS) of mefenamic acid (MFA) for improving pharmacodynamic activity. Methodology & results: Solubility assessment in various lipid excipients and optimization of pseudoternary plots were carried out for development of liquid SMEDDS. The optimized liquid SMEDD formulation was spray dried to solid dosage form and observed with enhanced amorphization or molecular dispersion of MFA in S-SMEDDS, as evident from x-ray diffractometry and differential scanning calorimetry studies. Enhanced in vitro dissolution rate of optimized formulation was observed, resulting in multifold enhancement in absorption profile of MFA, as compared with pure drug and marketed product. These studies further substantiate the dose reduction in SMEDDS by gaining equivalent therapeutic profile with marketed product. Enhanced analgesic and anti-inflammatory activity was observed with S-SMEDD formulations in acetic acid-induced writhings and carrageenan-induced paw edema models, respectively.

CONCLUSION

The optimized S-SMEDD formulation holds great promise for enhancement of its physiochemical and biological attributes.