Inhibitory effects of Clematis orientalis aqueous ethanol extract and fractions on inflammatory markers in complete Freund's adjuvant-induced arthritis in Sprague–Dawley rats

Launaea fragilis extract attenuated arthritis in rats through modulation of IL-1β, TNF-α, IL-6, NF-κB, COX-2, IL-4, and IL-10

Launaea fragilis (Asso) Pau is a Cholistan desert medicinal plant. Launaea species are used as traditional remedies against various inflammatory conditions. The current research was designed to evaluate the anti-nociceptive, anti-inflammatory, and anti-arthritic potential of ethanolic extract of L. fragilis (Et-LF). The plant extract was prepared by triple maceration. GC-MS screening explored the presence of various bioactive phytoconstituents including n-tetracosanol-1, 1-heptacosanol, and n-hexadecanoic acid. DPPH assay demonstrated the antioxidant potential of Et-LF. Safety profile data indicated that Et-LF was safe up to the oral dose of 5000 mg/kg in female rats. Anti-nociceptive activity of Et-LF was assessed in hot plate method and acetic acid-induced writhing model and the results suggested that Et-LF had significant analgesic effects in both animal models. Carrageenan, histamine, and serotonin-induced edema models were used to estimate the anti-inflammatory effects of Et-LF and were found to prevent paw edema development dose dependently. The anti-arthritic effect of Et-LF was estimated in CFA-induced arthritic rat model. Treatment with Et-LF 125, 250, 500 and flurbiprofen (FP) 10 mg/kg/day significantly attenuated the paw edema, reversed the reduced body weight, and restored the altered hematological parameters in arthritic rats. Gene expression studies revealed the significant downregulation of IL-1β, TNF-α, IL-6, NF‑κB, and COX-2, and upregulation of IL-4 and IL-10 in arthritic rats treated with various doses of plant extract. Histological evaluation of ankle joints showed that Et-LF mitigated pannus formation, infiltration of inflammatory cells, and fibrous connective tissue formation in the diseased rats. Thereof, it may be concluded that the recent study demonstrated the anti-nociceptive, anti-inflammatory, and anti-arthritic effects ascribed to the signifying presence of phytoconstituents in L. fragilis.

High-Altitude Medicinal Plants as Promising Source of Phytochemical Antioxidants to Combat Lifestyle-Associated Oxidative Stress-Induced Disorders

Oxidative stress, driven by reactive oxygen, nitrogen, and sulphur species (ROS, RNS, RSS), poses a significant threat to cellular integrity and human health. Generated during mitochondrial respiration, inflammation, UV exposure and pollution, these species damage cells and contribute to pathologies like cardiovascular issues, neurodegeneration, cancer, and metabolic syndromes. Lifestyle factors exert a substantial influence on oxidative stress levels, with mitochondria emerging as pivotal players in ROS generation and cellular equilibrium. Phytochemicals, abundant in plants, such as carotenoids, ascorbic acid, tocopherols and polyphenols, offer diverse antioxidant mechanisms. They scavenge free radicals, chelate metal ions, and modulate cellular signalling pathways to mitigate oxidative damage. Furthermore, plants thriving in high-altitude regions are adapted to extreme conditions, and synthesize secondary metabolites, like flavonoids and phenolic compounds in bulk quantities, which act to form a robust antioxidant defence against oxidative stress, including UV radiation and temperature fluctuations. These plants are promising sources for drug development, offering innovative strategies by which to manage oxidative stress-related ailments and enhance human health. Understanding and harnessing the antioxidant potential of phytochemicals from high-altitude plants represent crucial steps in combating oxidative stress-induced disorders and promoting overall wellbeing. This study offers a comprehensive summary of the production and physio-pathological aspects of lifestyle-induced oxidative stress disorders and explores the potential of phytochemicals as promising antioxidants. Additionally, it presents an appraisal of high-altitude medicinal plants as significant sources of antioxidants, highlighting their potential for drug development and the creation of innovative antioxidant therapeutic approaches.

Characterization of the complete chloroplast genome of Clematis orientalis (Ranunculaceae)

The medicinal plant Clematis orientalis L. belongs to the family Ranunculaceae. In this study, we determined the complete chloroplast genome sequence of C. orientalis and its phylogenetic relationships with other species. The complete chloroplast genome of C. glauca is 159,518 bp in length, circular in structure, and has four regions including a large single-copy (LSC) region of 79,453 bp; a small single-copy (SSC) region of 17,997 bp; and two inverted repeat (IR) regions of 31,034 bp. The GC content of the genome is 38%, and those of LSC, SSC, and IR regions are 36.2, 31.4, and 42%, respectively. The genome encodes 129 unique genes, including 85 protein-coding genes, 36 tRNA genes, and eight rRNA genes. Phylogenomic analysis reveals that C. orientalis is most closely related to C. aethusifolia. This study contributes to better understanding of phylogenetic relationships of Ranunculaceae.

Geranium wallichianum D. Don Ex Sweet Ameliorates Rheumatoid Arthritis by Curtailing the Expression of COX-II and Inflammatory Cytokines as Well as by Alleviating the Oxidative Stress

Geranium wallichianum D. Don ex sweet traditionally been used as home remedy for backaches, joint pain, colic, and rheumatism. The objective of this study was to investigate the therapeutic benefits of plant in an adjuvant-induced arthritis paradigm. Immune-mediated rheumatoid arthritis was developed by injecting complete Freund’s adjuvant (CFA) into the hind paws of rats and the aqueous methanolic crude extract was administered. The animals were physically monitored for changes in paw edema size and arthritic score. Hematological parameters and systemic inflammatory indicators evaluated. Genetic expressions of tumor necrosis factor (TNF-α), interleukins (IL-1β, IL-6), necrosis factor (NF-κB), and cyclooxygenase (COX-II) enzyme were studied using real-time qPCR. PGE2 levels in blood were quantified through Enzyme Linked Immunosorbent Assay (ELISA). On the 14th day, Immunoglobulin E (IGE) exhibited a substantial decline in paw edema and arthritic score. At the doses of 500 mg/Kg (P ≤ .05) and 1000 mg/Kg (P ≤ .001), IGE significantly reduced TNF-α, interleukins, and COX-II mRNA expression. IGE significantly lowered the MDA levels at the doses of 500 and 1000 mg/Kg (13.18 ± .70 and 9.04 ± .26 μM/L respectively) as compared to arthritic control (30.82 ± 1.12 μM/L) group. IGE significantly improved the antioxidant enzyme activities of CAT and SOD (P ≤ .001) in treated animals. TNF-α, interleukins, and COX-II mRNA expression were also significantly reduced at the doses of 300 (P ≤ .05), 500 (P ≤ .01) and 1000 mg/Kg (P ≤ .001) which were expressed as fold changes. This study shows that Geranium wallichianum D. Don ex sweet has a strong potential to alleviate immune-mediated arthritis by lowering oxidative stress and downregulating the proinflammatory cytokines signaling mechanisms.

Caralluma tuberculata exhibits analgesic and anti-arthritic potential by downregulating pro-inflammatory cytokines and attenuating oxidative stress

Caralluma tuberculata N.E. Brown (Common name: Chongan), belonging to the family Asclepiadaceae is distributed widely in hilly areas of Dir, Swat, Kohat and in plain lands of Punjab, Pakistan. The plant has been used as a source of vegetable as well as home remedy for headache, muscle spasms and rheumatism. The present study was proposed to investigate the analgesic, anti-inflammatory and anti-arthritic potential of the aqueous methanolic extract of C. tuberculata (ICE). The dried shoots of plant were used to prepare aqueous methanolic extract (30:70) by 3 days thrice maceration and filtration followed by evaporation under reduced pressure. ICE was screened for the presence of phytochemicals using preliminary phytochemical analysis and HPLC. The antioxidant potential was evaluated through DPPH assay. Analgesic potential of ICE was studied using hot plate and tail immersion methods, and anti-inflammatory activity was performed using turpentine oil and carrageenan-induced inflammation models, in wistar albino rats. Formaldehyde-induced and Complete Freund's Adjuvant-induced arthritis models were used for the assessment of anti-arthritic activity of ICE and its effects on serum levels of PGE-2 as well as gene expression levels of pro-inflammatory cytokines were studied. ICE displayed a dose-dependent (300-1000 mg/Kg p.o.) analgesic effect in hot plate (maximum retention time of 10.87 and 13 s) and tail immersion (response time of 11 and 13.64 s) tests at the doses of 500 and 1000 mg/Kg, respectively. The extract exhibited a significant decrease in paw inflammation of rats at the doses of 500 and 1000 mg/Kg as compared to the disease control group. ICE also exhibited a remarkable decline in arthritic score and a dose-dependent drop in serum levels of prostaglandin E2. There was a significant suppression in the expression of TNF-α, IL-1β, IL-6, NF-κB and cyclooxygenase enzyme in treatment groups. This study concludes that Caralluma tuberculata exhibits strong analgesic, anti-inflammatory, antioxidant and anti-arthritic activities thus upholding the vernacular use of the plant for pain and rheumatism.

Venlafaxine demonstrated anti-arthritic activity possibly through down regulation of TNF-α, IL-6, IL-1β, and COX-2

Venlafaxine is a serotonin-norepinephrine reuptake inhibitor used to treat depression. Previous studies demonstrated its anti-nociceptive and anti-inflammatory activities through the suppression of pro-inflammatory cytokines. Present research aimed to explore its anti-arthritic potential. Different in-vitro assays including egg albumin, bovine serum albumin denaturation and human red blood cell (RBC) membrane stabilization assays along with in-vivo models of formaldehyde and complete Freund's adjuvant-induced arthritis were used to study its anti-arthritic effect. Venlafaxine inhibited egg albumin and bovine serum albumin denaturation and preserve the integrity of red blood cells membrane in concentration-dependent manner. In formaldehyde-induced arthritis venlafaxine significantly (p < 0.001) reduced the paw edema on treatment for 10 days. Chronic administration of venlafaxine for 28 days in Freund's adjuvant-induced arthritis model decreased the paw volume (p < 0.001), arthritic index (p < 0.01), flexion pain score (p < 0.05), mobility score (p < 0.05), and improved the stance score (p < 0.05). Venlafaxine also significantly declined the rheumatoid factor (p < 0.01) and C-reactive protein (p < 0.05) levels and increased the RBC count (p < 0.01) and Hb value (p < 0.001). Upon PCR analysis venlafaxine remarkably turndown the mRNA expression of TNF-α, IL-6, IL-1β, and COX-2. Taken together it is inferred from current findings that venlafaxine possesses the significant anti-arthritic activity and could be a potential therapeutic option for the treatment of rheumatoid arthritis.

Potential of ephedrine to suppress the gene expression of TNF-α, IL-1β, IL-6 and PGE2: A novel approach towards management of rheumatoid arthritis

AIMS

Rheumatoid arthritis (RA) is a complicated perpetual auto-immune disorder allied with synovial hyperplasia, hyperalgesia, bone destruction, cartilage erosion and eventually physical impairment. Dysregulation of the sympathetic nervous system (SNS) is a reported hallmark of rheumatoid arthritis. Drugs targeting adrenergic receptors may be suitable to attenuate arthritis.

MAIN METHODS

This experimental work employed ephedrine (adrenergic agonist) for appraisal of its anti-arthritic potential by using CFA-provoked arthritic animal model. Physical parameters (Paw volume/diameter, arthritic index and weight) were assessed through whole study period. Blood sample was drawn by cardiac puncture for various tests like RF value, C-RP, ELISA, RFTs and LFTs. RNA was isolated from blood and expression of inflammatory cytokines was estimated through q-PCR.

KEY FINDINGS

Ephedrine alleviated swelling in paw and reinstated the body weight, hematological and biochemical indices of experimental animal. This drug (40 mg/kg PO) significantly (p < 0.001) reduced the expression (measured as percent expression) of tumor necrosis factor-α, interleukin-1β and interleukin-6 (54, 59 and 49% respectively) in arthritic animals. On the other side, cell derived anti-inflammatory mediators were expressed more in animals treated with same dose of ephedrine. Furthermore, inhibitory effect on expression of PGE2 was significantly (p < 0.001) observed in all treatment groups of ephedrine in comparison with standard treatment.

SIGNIFICANCE

This study ascertained the ephedrine as prospective therapeutic alternative candidate for treatment of RA but limited for clinical investigations.

The Role of Natural Products in Rheumatoid Arthritis: Current Knowledge of Basic In Vitro and In Vivo Research

Rheumatoid arthritis (RA) is an autoimmune disorder affecting a vast variety of the population. The onset of RA as well as the development of systematic immunization is affected by both genetic and environmental risk factors. This review aims to point out the role of natural products in the management of RA, focusing on the reports of basic research (in vitro and animal studies) emphasizing the antioxidant and anti-inflammatory properties considered in the field of RA. A systematic screening of the relevant literature was carried out on PubMed, Google Scholar, and Scopus with the following criteria: publication date, 2015-2020; language, English; study design, in vitro or animal models; and the investigation of one or several natural products in the context of RA, including, when available, the molecular mechanisms implicated. A total of 211 papers were initially obtained and screened. In vitro and animal studies referring to 20 natural products and 15 pure compounds were ultimately included in this review. The outcomes of this work provide an overview of the methods employed in basic research over the past five years, with emphasis on the limitations presented, while demonstrating the potential benefits of utilizing natural products in the management of RA as supported by in vitro and animal studies.

Iridoid glycosides from Morinda officinalis How. exert anti-inflammatory and anti-arthritic effects through inactivating MAPK and NF-κB signaling pathways

Background

The root of Morinda officinalis How. (MO, the family of Rubiaceae) has long been used to treat inflammatory diseases in China and other eastern Asian countries, and iridoid glycosides extracted from MO (MOIG) are believed to contribute to this anti-inflammatory effect. However, the mechanism underlying the anti-inflammatory and anti-arthritic activities of MOIG has not been elucidated. The aim of the present study was to determine how MOIG exerted anti-inflammatory and anti-arthritic effects in vivo and in RAW 264.7 macrophages.

Methods

MOIG were enriched by XDA-1 macroporous resin. The maximum feasible dose method was adopted to evaluate its acute toxicity. The analgesic effect of MOIG was evaluated by acetic acid writhing test and the anti-inflammatory effect was evaluated by cotton-pellet granuloma test in rats and air pouch granuloma test in mice. The anti-arthritic effect was evaluated by establishing an adjuvant arthritis model induced by Complete Freund’s Adjuvant (CFA). The viability of the cultured RAW 264.7 macrophages was assessed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay. The anti-inflammatory activity was evaluated by measuring NO, IL-1β, IL-6 and TNF-α levels in LPS-stimulated RAW 264.7 cells. The protein level of inflammatory responsive genes was evaluated by Western blot analysis.

Results

MOIG had no significant toxicity at maximum feasible dose of 22.5 g/kg. MO extracts and MOIG (50,100 and 200 mg/kg) all evoked a significantly inhibitory effects on the frequency of twisting induced by acetic acid in mice compared with the model control group. Administration of MO extracts and MOIG markedly decreased the dry and wet weight of cotton pellet granuloma in rats and air pouch granuloma in mice. MOIG significantly attenuated the paw swelling and decreased the arthritic score, weight loss, spleen index, and the serum level of inflammatory factors IL-1β, IL-6 and IL-17a in CFA-induced arthritic rats. MOIG inhibited the production of inflammatory cytokines in LPS-stimulated RAW264.7 cells, and the expressions of iNOS, COX-2 and proteins related to MAPK and NF-κB signaling pathways in LPS-stimulated RAW 264.7 macrophages.

Conclusion

MOIG exerted anti-inflammatory and anti-arthritic activities through inactivating MAPK and NF-κB signaling pathways, and this finding may provide a sound experimental basis for the clinical treatment of rheumatoid arthritis with MOIG.