Prevention of the progression of adjuvant induced arthritis by oral supplementation of Indian fresh water mussel (Lamellidens marginalis) aqueous extract in experimental rats

Chemometric profiling and anti-arthritic activity of aerial parts of Glinus oppositifolius (L.) Aug. DC

ETHNOPHARMACOLOGICAL RELEVANCE

Glinus oppositifolius (L.) Aug. DC. belongs to the family Molluginaceae, an annual prostrate herb traditionally used to treat inflammations, arthritis, malarial, wounds, fevers, diarrhoea, cancer, stomach discomfort, jaundice, and intestinal parasites. However, the anti-arthritic activity of the aerial part has still not been reported.

AIM OF THE STUDY

To investigate the antioxidant and anti-arthritic activity of G. oppositifolius in Complete Freund's Adjuvant (CFA) induced rats.

MATERIALS AND METHODS

The dried aerial parts of this plant material were defatted with n-hexane and extracted by methanol using a soxhlet apparatus. The in vitro anti-arthritic activity of methanolic extract of G. oppositifolius (MEGO) was evaluated in protein denaturation, membrane stabilization, and inhibition of proteinase assay at 25, 50, 100, 200, and 400 μg/ml concentrations. Female Wistar rats were immunized sub-dermally into the right hind paw with 0.1 ml of CFA. Rats were administered with MEGO at doses of 200 and 400 mg/kg once daily for fourteen days after arthritis induction. Assessment of arthritis was performed by measuring paw diameter, arthritic index, arthritic score, body weight, organ weight, and hematological and biochemical parameters, followed by the analysis of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), interleukin-1-beta (IL-1β), cyclooxygenase-2 (COX-2), interleukin 13 (IL-13) and interleukin 10 (IL-10) and histopathological study. In vivo antioxidant effect was investigated in enzymatic assays. The presence of phytoconstituents was analyzed by Gas Chromatography-Mass Spectrometry (GC-MS) and Liquid Chromatography-Mass Spectrometry (LC-MS), respectively. In silico molecular docking study of the compounds was carried out against COX-2, IL-1β, IL-6, and TNF-α using AutoDock 4.2 and BIOVIA-Discovery Studio Visualizer software.

RESULTS

MEGO's in vitro anti-arthritic activity showed dose-dependent inhibition of protein denaturation, membrane stabilization, and proteinase inhibition, followed by significant in vivo anti-arthritic activity. The rats treated with MEGO showed tremendous potential in managing arthritis-like symptoms by restoring hematological, biochemical, and histological changes in CFA-induced rats. MEGO (200 and 400 mg/kg) showed a significant alleviation in the levels of hyper expressed inflammatory mediators (TNF-α, IL-1β, and IL-6) and oxidative stress (SOD, CAT, GSH, and LPO) in CFA-induced rats. Spergulagenin-A as identified by LC-MS analysis, exhibited the highest binding affinity against COX-2 (-8.6), IL-1β (7.2 kcal/mol), IL-6 (-7.4 kcal/mol), and TNF-α (-6.5 kcal/mol).

CONCLUSIONS

Provided with the comprehensive investigation, methanolic extract of G. oppositifolius against arthritic-like condition is a proof of concept that revalidates its ethnic claim. The presence of Spergulagenin-A might be responsible for the anti-arthritic activity.

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.

A global synthesis of ecosystem services provided and disrupted by freshwater bivalve molluscs

Identification of ecosystem services, i.e. the contributions that ecosystems make to human well-being, has proven instrumental in galvanising public and political support for safeguarding biodiversity and its benefits to people. Here we synthesise the global evidence on ecosystem services provided and disrupted by freshwater bivalves, a heterogenous group of >1200 species, including some of the most threatened (in Unionida) and invasive (e.g. Dreissena polymorpha) taxa globally. Our systematic literature review resulted in a data set of 904 records from 69 countries relating to 24 classes of provisioning (N = 189), cultural (N = 491) and regulating (N = 224) services following the Common International Classification of Ecosystem Services (CICES). Prominent ecosystem services included (i) the provisioning of food, materials and medicinal products, (ii) knowledge acquisition (e.g. on water quality, past environments and historical societies), ornamental and other cultural contributions, and (iii) the filtration, sequestration, storage and/or transformation of biological and physico-chemical water properties. About 9% of records provided evidence for the disruption rather than provision of ecosystem services. Synergies and trade-offs of ecosystem services were observed. For instance, water filtration by freshwater bivalves can be beneficial for the cultural service 'biomonitoring', while negatively or positively affecting food consumption or human recreation. Our evidence base spanned a total of 91 genera and 191 species, dominated by Unionida (55% of records, 76% of species), Veneroida (21 and 9%, respectively; mainly Corbicula spp.) and Myoida (20 and 4%, respectively; mainly Dreissena spp.). About one third of records, predominantly from Europe and the Americas, related to species that were non-native to the country of study. The majority of records originated from Asia (35%), with available evidence for 23 CICES classes, as well as Europe (29%) and North America (23%), where research was largely focused on 'biomonitoring'. Whilst the earliest record (from 1949) originated from North America, since 2000, annual output of records has increased rapidly in Asia and Europe. Future research should focus on filling gaps in knowledge in lesser-studied regions, including Africa and South America, and should look to provide a quantitative valuation of the socio-economic costs and benefits of ecosystem services shaped by freshwater bivalves.

Nerolidol: a potential approach in rheumatoid arthritis through reduction of TNF-α, IL-1β, IL-6, NF-kB, COX-2 and antioxidant effect in CFA-induced arthritic model

Rheumatoid arthritis is primarily associated with inflammation and increased level of proinflammatory cytokines which are released by immune cells, macrophages or activation of arachidonic acid metabolism. The expression of these cytokines, oxidative free radicals and the activation of COX-2 enzymes are crucial targets for chronic inflammation. On the basis of established anti-inflammatory efficacy of nerolidol, the primary study was further appraised to determine its approach against Freund's complete adjuvant (CFA) rheumatoid model. Arthritis was induced by inoculation of 0.1 mL CFA injection into the left hind footpad of rats. Anti-arthritic potential of nerolidol (at 200, 400 and 800 mg/kg doses) was assessed by measuring the paw volume, body weight, serum analysis, histopathological and radiographs of ankle joints. Expressions of cytokine's panels such as IL-10, IL-4, COX-2, NF-kB, TNF-α, IL-6, PGE-2 and IL-1β were determined by real-time qPCR. Antioxidant enzyme analyses were conducted by measuring the SOD, POD and catalase activity from serum and equated with arthritic control group. Nerolidol prevented body weight loss, stabilized biochemical and haematological homeostasis and significantly reduced the paw volume. Furthermore, X-ray and histopathological assessment of ankle joints showed an improvement in the joint structure of rats treated with nerolidol. Besides that, overexpression of gene pointers like TNF-α, IL-1β, IL-6, NF-kB, PGE-2 and COX-2 in CFA-treated control rats were also reversed with nerolidol. This anti-arthritic mechanism was further supported by the increased level of IL-10, IL-4 and serum antioxidant activity. The present findings demonstrate that nerolidol reduced adjuvant arthritis by downregulating the proinflammatory cytokines and upregulating the aforementioned anti-inflammatory cytokines and may be used as a therapeutic substance for the management of human rheumatoid arthritis.

Molluscan Compounds Provide Drug Leads for the Treatment and Prevention of Respiratory Disease

Respiratory diseases place an immense burden on global health and there is a compelling need for the discovery of new compounds for therapeutic development. Here, we identify research priorities by critically reviewing pre-clinical and clinical studies using extracts and compounds derived from molluscs, as well as traditional molluscan medicines, used in the treatment of respiratory diseases. We reviewed 97 biomedical articles demonstrating the anti-inflammatory, antimicrobial, anticancer, and immunomodulatory properties of >320 molluscan extracts/compounds with direct relevance to respiratory disease, in addition to others with promising bioactivities yet to be tested in the respiratory context. Of pertinent interest are compounds demonstrating biofilm inhibition/disruption and antiviral activity, as well as synergism with approved antimicrobial and chemotherapeutic agents. At least 100 traditional medicines, incorporating over 300 different mollusc species, have been used to treat respiratory-related illness in cultures worldwide for thousands of years. These medicines provide useful clues for the discovery of bioactive components that likely underpin their continued use. There is particular incentive for investigations into anti-inflammatory compounds, given the extensive application of molluscan traditional medicines for symptoms of inflammation, and shells, which are the principal molluscan product used in these preparations. Overall, there is a need to target research toward specific respiratory disease-related hypotheses, purify bioactive compounds and elucidate their chemical structures, and develop an evidence base for the integration of quality-controlled traditional medicines.

Antiarthritic Potential of Comprehensively Standardized Extract of Alternanthera bettzickiana: In Vitro and In Vivo Studies

Alternanthera bettzickiana is being used as a folk remedy for treating arthritis by conventional healers in Thailand. The current research was undertaken to explore the antiarthritic potential of A. bettzickiana ethanolic extract (ABEE). Plant characterization, molecular docking, and in vitro and in vivo (ABEE at 250, 500, and 1000 mg/kg was administered orally to rats once daily for 28 days) studies to explore the antiarthritic effect and enzyme-linked immunosorbent assay (ELISA) and real-time polymerase chain reaction (RT-PCR) analyses were performed. Oxidative stress biomarkers (superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA)) in the serum and histopathological and radiographic assessment of joints were also carried out. Gallic acid, catechin, chlorogenic acid, sinapic acid, quercetin, and γ- and α-tocopherol were identified in high-performance liquid chromatography (HPLC). Molecular docking revealed a strong interaction between these compounds and cyclooxygenase (COX) enzymes. The extract significantly subdued paw swelling and arthritic scoring, inhibited cachexia, and considerably improved biochemical and hematological modifications. SOD and CAT levels increased and the MDA level decreased in ABEE-treated rats dose-dependently. Radiographic and histopathological analyses also supported the antiarthritic effect of ABEE, which was linked with the downregulation of nuclear factor (NF)-kB, COX-2, interleukin (IL)-6, tumour necrosis factor (TNF)-α, and IL-1β and upregulation of IL-10, I-kB, and IL-4 as compared to disease control rats. Results suggested that A. bettzickiana possessed antiarthritic potential, supporting its folkloric use for treating rheumatoid arthritis.

Ribes orientale: A novel therapeutic approach targeting rheumatoid arthritis with reference to pro-inflammatory cytokines, inflammatory enzymes and anti-inflammatory cytokines

ETHNOPHARMACOLOGICAL RELEVANCE

The roots of Ribes orientale (Family Grossulariaceae) have long been used as a folk remedy to treat rheumatism and joints pain in Northern Areas of Pakistan.

AIM OF THE STUDY

The purpose of study was to observe the preventive efficacy of roots of Ribes orientale (RO) aqueous ethanolic extract (30:70) and its aqueous and n-butanol fractions in treating rheumatoid arthritis and to determine its possible mechanism of action.

MATERIAL AND METHODS

Arthritis was evaluated in vitro using heat induced bovine serum albumin and egg albumin denaturation and membrane stabilizing assays at 50-6400 μg/ml concentration of extract/fractions whereas, in vivo arthritis was evaluated at 50, 100, 200 mg/kg doses of extract/fractions in formaldehyde model by measuring rat paw volume/diameter. Moreover, highest effective dose (200 mg/kg) of extract/fractions was evaluated in Freünd complete adjuvant (FCA) model. Arthritis was induced in Sprague Dawley rats by immunization with 0.1 ml FCA in left footpad. RO extract/fractions at 200 mg/kg were orally administered from day 0, 30 min prior to adjuvant injection and sustained for 28 days. Paw volume/diameter, arthritic score, body weight, and hematological (WBC, RBC, ESR, Hb and Platelet count) and biochemical (AST, ALT, ALP, urea, creatinine, CRP and RF) parameters were observed. The mRNA expression levels of COX-2, IL-1β, IL-6, NF-kB, TNF-α, IL-4 and IL-10 were measured by real time reverse transcription polymerase chain reaction (RT-PCR) whereas, PGE2 and TNF-α levels in serum samples were measured by Enzyme linked immunosorbent assay (ELISA). Furthermore, radiographs of hind paws and histological changes in ankle joint were analyzed in adjuvant injected rats. The anti-oxidant activity of plant extract and fractions was evaluated using DPPH and reducing power assays. In addition, phytochemistry, total phenolic and flavonoid contents, and HPLC analysis of most active fraction (aqueous fraction) were performed.

RESULTS

Results showed that RO extract and fractions (notably aqueous fraction) significantly reduced protein denaturation and protected erythrocyte membrane in concentration dependent manner. Similarly, extract/fractions induced dose-dependent decrease in paw volume/diameter in the formaldehyde model. Plant extract and fractions significantly suppressed paw swelling and arthritic score, prevented cachexia and remarkably ameliorated hematological and biochemical changes. Furthermore, RO extract/fractions downregulated gene expression levels of PGE2, COX-2, IL-1β, IL-6, NF-kB and TNF-α whereas, upregulated those of IL-4 and IL-10, compared with FCA control rats. The radiographic and histopathologic improvement in joint architecture was also observed in RO treated rats. Piroxicam, used as reference drug, also significantly suppressed arthritis. Additionally, plant exhibited notable anti-oxidant activity and phytochemical analysis revealed the presence of flavonoids and polyphenols.

CONCLUSION

Results indicated that suppression of pro-inflammatory enzymes/cytokines, inhibition of protein denaturation, lysosomal membrane stabilizing abilities, and redox/free radical scavenging properties of RO extract and fractions support anti-arthritic and immunomodulatory property of Ribes orientale that might be due to its polyphenolic and flavonoid constituents. This suggests that Ribes orientale roots may be used as a therapeutic agent for treating human arthritis.

Ephedra gerardiana aqueous ethanolic extract and fractions attenuate Freund Complete Adjuvant induced arthritis in Sprague Dawley rats by downregulating PGE2, COX2, IL-1β, IL-6, TNF-α, NF-kB and upregulating IL-4 and IL-10

ETHNOPHARMACOLOGICAL RELEVANCE

The whole plant, roots and stems of Ephedra gerardiana (Family Ephedraceae) have long been used as a folk remedy to treat rheumatism and painful joints in Northern Areas of Pakistan.

AIM OF THE STUDY

The purpose of study was to observe the preventive efficacy of Ephedra gerardiana (EG) aerial parts in treating rheumatoid arthritis using Freund's complete adjuvant (FCA) induced arthritis in rat model and to determine its possible mechanism of action.

MATERIAL AND METHODS

Arthritis was induced in Sprague Dawley rats by immunization with 0.1 ml FCA in left footpad. EG aqueous ethanolic extract (30:70) and its aqueous, n-butanol and ethyl acetate fractions at 200 mg/kg were orally administered from day 0, 30 min prior to adjuvant injection and sustained for 28 days. Paw volume/diameter, arthritic score, body weight, and hematological (WBC, RBC, ESR, Hb and Platelet count) and biochemical (AST, ALT, ALP, urea, creatinine, CRP and RF) parameters were observed. The mRNA expression levels of COX-2, IL-1β, IL-6, NF-kB, TNF-α, IL-4 and IL-10 were measured by real time reverse transcription polymerase chain reaction (RT-PCR) while, PGE2 and TNF-α levels in serum samples were measured by Enzyme linked immunosorbent assay (ELISA). Moreover, radiographs of hind paws and histological changes in ankle joint were analyzed in adjuvant injected rats. In addition, anti-oxidant activity of plant extract and fractions was also evaluated using DPPH and reducing power assays. Also, preliminary phytochemistry and total phenolic and flavonoid contents were investigated in most active fraction (aqueous fraction).

RESULTS

EG extract and fractions (notably aqueous fraction) significantly suppressed paw swelling and arthritic score, prevented cachexia and remarkably ameliorated hematological and biochemical changes. Furthermore, the overproduction of PGE2, COX-2, IL-1β, IL-6, NF-kB and TNF-α were remarkably attenuated in all EG treated rats, however, IL-4 and 10 were markedly increased. The radiographic and histopathologic improvement in joint architecture was also observed in EG treated rats. Piroxicam, used as reference drug, also significantly suppressed arthritis. Additionally, plant exhibited notable anti-oxidant activity and phytochemical analysis revealed the presence of alkaloids, flavonoids, phenols, tannins, saponins and glycosides.

CONCLUSION

These results indicate that EG extract and fractions significantly attenuated adjuvant arthritis in rats by decreasing the levels of aforementioned pro-inflammatory and increasing the levels of anti-inflammatory mediators. This suggests that Ephedra gerardiana aerial parts might be used as a therapeutic agent for treating human arthritis.

Review of anti-inflammatory, immune-modulatory and wound healing properties of molluscs

ETHNOPHARMACOLOGICAL RELEVANCE

This review focuses on traditional and contemporary anti-inflammatory uses of mollusc-derived products summarising all the in vitro, in vivo and human clinical trials that have tested the anti-inflammatory activity of molluscan natural products. Inflammatory conditions, burns and wounds have been an ongoing concern for human health since the early era of civilisation. Many texts from ancient medicine have recorded the symptoms, signs and treatments for these conditions. Natural treatments are well-documented in traditional European medicine, Traditional Chinese Medicine (TCM), Siddha and ancient Mediterranean and African traditional medicine and include a surprisingly large number of molluscan species.

MATERIALS AND METHODS

An extensive review of the Materia Medica and scientific literature was undertaken using key word searches for "mollusc" and "anti-inflammatory" or "immunomodulatory" or "wound healing".

RESULTS

Molluscs have been used in ethnomedicine by many traditional cultures to treat different aspects of inflammatory conditions. We found 104 different anti-inflammatory preparations from a variety of molluscan species, of which 70 were from the well-documented Traditional Chinese Medicine (TCM). This traditional use of molluscs has driven the testing for inflammatory activity in extracts from some species in the phylum Mollusca, with 20 in vitro studies, 40 in vivo animal studies and 14 human clinical trials performed to substantiate the anti-inflammatory and wound healing activity of molluscs. Some of these studies have led to the approval of mollusc-derived products to be used as over-the-counter (OTC) nutraceuticals, like Lyprinol® and Biolane™ from the New Zealand green lipped mussel Perna canaliculus.

CONCLUSION

Natural products provide important leads for the development of pharmaceuticals, including anti-inflammatory agents. Only a small proportion of the molluscan traditional medicines have been tested to confirm their anti-inflammatory activity and most screening studies have tested crude extracts from molluscs without any chemical characterisation. This highlights the need for further research to strategically identify the anti-inflammatory compounds in molluscan medicines to provide leads for novel anti-inflammatory drugs in the future.

5,7,3′-Triacetyl Hesperetin Suppresses Adjuvant-Induced Arthritis in Rats through Modulating JAK2/STAT3 Pathway

This work was designed to identify the effect of 5,7,3′-triacetyl hesperetin (TAHP) on rat adjuvant arthritis (AA) and further clarify the possible role of TAHP on modulating Janus kinase signal transducers and activators (JAK/STAT in this process. Freund's complete adjuvant was used to induce AA in rats. TAHP (33, 66, 132 mg/kg) was administered intragastrically. Secondary paw swelling, polyarthritis index, index of immune organs and histopathological assessment were used to evaluate the effects of TAHP on AA in rats. IL-6 in serum and in synovial tissues was examined with ELISA and RT-PCR. In addition, JAK2/STAT3 pathway-related key molecules mRNA expression in synovial tissues of AA rats were detected by RT-PCR and western blot respectively. It was found that TAHP (66, 132 mg/kg) could significantly inhibit secondary paw swelling, restore the index of immune organs and reduce polyarthritis index. Results of histopathological assessment showed that TAHP clearly ameliorated the pathological changes in AA rats. TAHP could downregulate the level of IL-6 in serum and in synovial tissues of AA rats. Besides, treatment with TAHP could decrease mRNA expressions of STAT3 and JAK2, as well as the ratio of p-JAK2/JAK2 protein and p-STAT3/STAT3 protein from synovial tissues. Thus, the paper demonstrated that TAHP had a therapeutic effect on AA in rats and the mechanisms were partly associated with modulating proinflammatory cytokine IL-6 production in serum and in synovial tissues and inhibiting excessive activation of JAK2/STAT3 signaling pathway which might play a crucial role in the pathogenesis of AA.

Antioxidant content and activity of the Indian fresh-water pearl mussel in the prevention of arthritis in an experimental animal model

The flesh of the Indian fresh-water mussel, Lamellidens marginalis (LM; Lamarck, 1819), is the byproduct of pearl culture and a cheap protein source. The present study investigated the antioxidant content of this ethnomedicinally cited species to outline its importance in food security and disease prevention. LM was found to be rich in polyphenol antioxidants with good correlation with its reducing capacity. LM also showed a significant free-radical-scavenging activity, H2O2-scavenging activity and Fe-chelating activity. To study the effect of this dietary antioxidant against oxidative stress, we took inflammatory arthritis as a model. LM-treated arthritis rats showed a higher antioxidant defence system with elevated superoxide dismutase, total thiol, glutathione S transferase, glutathione peroxidase, total antioxidant status and catalase concentration of haemolysate. Oxidative stress markers like serum thiobarbituric acid-reacting substances, methyl glyoxal, NO and total oxidant status levels were decreased in LM-treated arthritis rats. Hence, the dietary antioxidants of LM were found to be effective in the prevention of oxidative stress in inflammatory arthritis. In conclusion, LM, the cash-crop byproduct, provides a rare opportunity for income and nutrition, not only by providing cheap and available energy, protein and dietary factors, but also by providing antioxidants effective against chronic inflammatory disease.