Carvedilol can attenuate histamine-induced paw edema and formaldehyde-induced arthritis in rats without risk of gastric irritation

β-Citronellol: a potential anti-inflammatory and gastro-protective agent-mechanistic insights into its modulatory effects on COX-II, 5-LOX, eNOS, and ICAM-1 pathways through in vitro, in vivo, in silico, and network pharmacology studies

BACKGROUND

The current study aimed to evaluate the anti-inflammatory, anti-oxidant, and pronounced gastro-protective activities of β- Citronellol using in vitro, in vivo assays and in silico approaches.

METHODS

In vitro assays, denaturation of bovine serum albumin, egg protein, and human Red Blood Cells (RBCs) membrane stabilization were performed, using Piroxicam as standard. For in vivo assessment, Histamine (0.1 ml from 1% w/v) and Formaldehyde (0.1 ml from 2% v/v) were used to mediate inflammation. In silico molecular docking and network pharmacology were employed to probe the possible target genes mediating gastroprotective effect of β-Citronellol at 25, 50, and 100 mg/kg, using indomethacin-induced (25 mg/kg i.p) gastric ulcer in rats. Moreover, Gastric tissues were evaluated for morphological, histopathological, and bio-chemical analysis of PGE2, COX-I, COX-II, 5-LOX, eNOS, ICAM-1, oxygen-free radical scavengers (SOD, CAT), and oxidative stress marker (MDA).

RESULTS

β-Citronellol prevented denaturation of proteins and RBCs membrane stabilization with maximum effect observed at 6,400 µg/mL. Citronellol decreased rat's paw edema. Network pharmacology and docking studies revealed gastro-protective potential of Citronellol possibly mediated through arachidonic acid pathways by targeting COX-I, COX-II, PGE2, and 5-LOX. Citronellol reduced the ulcer indices, and histopathological changes. Further, β-Citronellol (50 and 100 mg/kg) increased gastric PGE2, COX-1, and eNOS; while suppressing COX-2, 5-LOX and ICAM-1. Citronellol markedly enhanced the oxidative balance in isolated rat stomach tissues.

CONCLUSIONS

The anti-inflammatory, anti-oxidant, and gastro-protective effects of β-Citronellol against indomethacin-induced gastric ulcer model in rats through mediating COX-I, COX-II, PGE2, 5-LOX, eNOS, and ICAM-1 inflammatory markers.

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.

Synthesis, Spectroscopic and Biological Investigation of a New Ca(II) Complex of Meloxicam as Potential COX-2 Inhibitor

Drug development on basis of coordination compounds provides versatile structural and functional properties as compared to other organic compounds. In the present study, a new Ca(II) complex of meloxicam was synthesized and characterized by elemental analysis, FT-IR, UV–Vis, ¹³C NMR, SEM–EDX, powder XRD and thermal analysis (TGA). The Ca(II) complex was investigated for its in vitro, in vivo biological activities and in silico docking analysis against COX-1 and COX-2. The spectral analysis indicates that the meloxicam acts as a deprotonated bidentate ligand (coordinated to the metal atom through the amide oxygen and the nitrogen atom of the thiazolyl ring) in the complex. SEM–EDX and powder XRD analysis depicted crystalline morphology of Ca(II) complex with a crystalline size of 32.86 nm. The in vitro biological activities were evaluated by five different antioxidant methods and COX inhibition assay, while in vivo activities were evaluated by carrageenan-, histamine- and PGE₂-induced paw edema methods and acetic acid-induced writhing test. The Ca(II) complex showed prominent antioxidant activities and was found to be more selective toward COX-2 (43.77) than COX-1 as compared to meloxicam. It exhibited lower toxicity (LD₅₀ 1000 mg/Kg) and significantly inhibited carrageenan- and PGE₂-induced inflammation at 10 mg/Kg (P < 0.05), but no significant effect was observed on histamine-induced inflammation. Moreover, Ca(II) complex significantly reduced the number of writhes induced by acetic acid (P < 0.05). The in silico molecular docking data revealed that Ca(II) complex obstructed COX-2 (dock score 6438) more effectively than COX-1 (dock score 5732) as compared to meloxicam alone.

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.

Sodium R-lipoate and enzymatically-modified isoquercitrin suppressed IgE-independent anaphylactic reactions and stress-induced gastric ulceration in mice

Anaphylaxis is a life-threatening allergic reaction, for which the worldwide prevalence is rapidly increasing. The currently used synthetic antiallergic drugs have a high tendency to cause adverse effects, like gastric ulcers, in long-term use. Therefore, a great deal of attention has been given to develop new safer and more effective antiallergic agents from natural compounds that are chemically/enzymatically-modified. Here, we evaluated/compared the efficacy of two different doses (50 and 100 mg/kg body weight "b.w", given orally) of sodium R-lipoate (NaRLA) and enzymatically-modified isoquercitrin (EMIQ) in alleviating both local/systemic non-immunological anaphylactic reactions and stress-induced gastric ulceration in mice, in comparison with sulfasalazine (SSZ) as a reference drug. The results indicated that the pre-treatment of animals with NaRLA or EMIQ (especially at 100 mg/kg b.w) completely succeeded, as SSZ, in alleviating the hind paw edema induced by either histamine or compound 48/80 (Cpd 48/80). Furthermore, NaRLA and EMIQ prevented the mast cell degranulation and anaphylactic shock caused by Cpd 48/80 (in a dose-dependent manner) and reduced significantly (P < 0.001) the histamine release from the mouse peritoneal mast cells, like SSZ. Moreover, their use was associated with alleviating both gastric histopathological and biochemical alterations in the water-restraint stress (WRS) mice model towards the control values. They also decreased the percentage of degranulated mesenteric mast cells in the WRS mice model. In conclusion, our findings provide possibility that both NaRLA and EMIQ may serve as an effective therapeutic agents for mast cells-dependent anaphylactic reactions without risks of inducing gastric ulcers.

Optimization and Development of Methotrexate- and Resveratrol-Loaded Nanoemulsion Formulation Using Box-Behnken Design for Rheumatoid Arthritis

Methotrexate (MTX) is the first line of choice for the management of rheumatoid arthritis (RA) and has been reported for its low bioavailability and side effects. Combination therapy has been widely investigated to overcome bioavailability issues and to reduce adverse effects associated with monotherapy. Various phytoconstituents such as resveratrol (RSV) and curcumin have been found to possess potent anti-inflammatory activity via downregulating the signaling of cytokines (interleukin [IL]-1, IL-6, and tumor necrosis factor alpha) and nuclear factor kappa B signaling. The prime objective of this study was to develop transdermal gel containing MTX-RSV loaded nanoemulsions (NEs) to overcome bioavailability issues and adverse effects of RA monotherapy. The NEs optimized by using Box-Behnken Design were incorporated within gel, and an in vitro skin permeation study performed on rat skin by using vertical Franz diffusion cells exhibited controlled drug release up to 48 h. Subsequently, anti-inflammatory and potential anti-arthritic activities of the combination in nanocarrier were assessed in rats and showed 78.76 ± 4.16% inhibition in inflammation and better anti-arthritic effects. Consequently, integration of dual delivery with nanotechnology can hopefully produce successful therapeutic options for rheumatic diseases.

Antiedematogenic and Anti-Inflammatory Activity of the Monoterpene Isopulegol and Its β-Cyclodextrin (β-CD) Inclusion Complex in Animal Inflammation Models

Isopulegol (ISO) is an alcoholic monoterpene widely found in different plant species, such as Melissa officinalis, and has already been reported to have a number of pharmacological properties. Like other terpenes, ISO is a highly volatile compound that is slightly soluble in water, so its inclusion into cyclodextrins (CDs) is an interesting approach to increase its solubility and bioavailability. Thus, our aim was to evaluate the antiedematogenic and anti-inflammatory activity of isopulegol and a β-cyclodextrin-isopulegol inclusion complex (ISO/β-CD) in rodent models. For the anti-inflammatory activity evaluation, antiedematogenic plethysmometry and acute (peritonitis and pleurisy), as well as chronic (cotton pellet-induced granuloma) anti-inflammatory models, were used. The docking procedure is used to evaluate, analyze, and predict their binding mode of interaction with H1 and Cox-2 receptors. The animals (n = 6) were divided into groups: ISO and ISO/β-CD, negative control (saline), and positive control (indomethacin and promethazine). ISO and ISO/β-CD were able to reduce acute inflammatory activity by decreasing albumin extravasation, leukocyte migration, and MPO concentration, and reducing exudate levels of IL-1β and TNF-α. ISO and ISO/β-CD significantly inhibited edematogenic activity in carrageenan- and dextran-induced paw edema. Moreover, both significantly reduced chronic inflammatory processes, given the lower weight and protein concentration of granulomas in the foreign body granulomatous inflammation model. The results suggest that the inclusion of ISO in β-cyclodextrins improves its pharmacological properties, with the histamine and prostaglandin pathways as probable mechanisms of inhibition, and also reinforces the anti-inflammatory profile of this terpene.

In Vitro and In Vivo Evaluation of Core-Shell Mesoporous Silica as a Promising Water-Insoluble Drug Delivery System: Improving the Dissolution Rate and Bioavailability of Celecoxib With Needle-Like Crystallinity

The objective of our study was to prepare mesoporous silica nanoparticles with a core-shell structure (CSMSNs) and improve the dissolution and bioavailability of celecoxib (Cxb), a water-insoluble drug, by changing its needle-like crystal form. CSMSNs are prepared by a core-shell segmentation self-assembly method. The S_BET and V_t of CSMSNs were 890.65 m²/g and 1.23 cm³/g, respectively. Cxb was incorporated into CSMSNs by the solvent evaporation method. The gastrointestinal irritancy of the CSMSNs was evaluated by a gastric mucosa irritation test. In vitro dissolution and in vivo pharmacokinetic tests were carried out to study the improvement in the dissolution behavior and oral bioavailability of Cxb. In conclusion, gastric mucosa irritation study indicated the good biocompatibility of CSMSNs. The cumulative dissolution of CSMSNs-Cxb is 86.2% within 60 min in SIF solution, which may be ascribed to the crystal form change caused by control of the nanochannel for CSMSNs. Moreover, CSMSNs could enhance the 9.9-fold AUC of Cxb. The cumulative dissolution and bioavailability of Cxb were both significantly enhanced by CSMSNs. CSMSNs with a core-shell structure are suitable as a carrier for a poorly water-soluble drug (Cxb).