The intensity of joint pain in relation to changes in serum TNFα during therapy with anti-TNFα inhibitors Abstract Introduction Tumor necrosis factor-alpha (TNFα) inhibitors have significantly improved the outcomes of treatment for rheumatoid arthritis (RA). In the present study, we aimed to determine whether serum levels of TNFα during therapy with TNFα inhibitors do really reflect the disease activity and correspond to the intensity of pain experienced. Materials and methods Thirty RA patients were examined before and after 12 weeks of routine therapy with TNFα inhibitors. Serum levels of TNFα were measured with a high-sensitivity immunoassay and related to patients’ clinical and biochemical status. Disease activity was assessed by the modified disease activity score (DAS28). Results A median relative change in TNFα was 13%. The patients were stratified according to whether the relative change in serum TNFα after therapy was above or below this median value. The patients from both subgroups did not differ in baseline characteristics and response to therapy. However, the patients in whom serum TNFα increased after therapy above the median value had more tender joints after treatment than patients from the other group. Consequently, the number of tender joints after the treatment correlated with absolute TNFα concentrations at this time (r = 0.37; p = 0.049) and the magnitude of changes in serum TNFα correlated with a change in the number of tender joints (r = − 0.48; p = 0.008). Conclusions Circulating TNFα levels did not decrease in RA patients treated with TNFα inhibitors, despite clinical and biochemical improvement. It is possible, that circulating TNFα is responsible for the persistence of joint pain in this group of patients.

4-Phenylbutyric acid protects against vasculitic peripheral neuropathy induced by ischaemia–reperfusion through attenuating endoplasmic reticulum stress Abstract Vasculitic peripheral neuropathy (VPN) is characterized by acute-to-subacute onset of painful sensory and motor disturbances that result from inflammatory obliteration of nerve blood vessels and subsequent ischaemic injury. Endoplasmic reticulum (ER) stress has been implicated in the pathogenesis of various peripheral neuropathies, and 4-phenylbutyric acid (4-PBA) is a chemical chaperone that inhibits ER stress signaling. We investigated the effects of 4-PBA on neuropathic pain associated with VPN induced by ischaemia–reperfusion (IR) and its underlying mechanisms. Male Sprague-Dawley rats were allocated to one of the following groups: sham, sham + 4-PBA, IR, and IR + 4-PBA. IR was achieved by occluding the femoral artery for 4 h followed by reperfusion. The behavioral parameters were assessed, and the expression of ER stress markers and nuclear factor (NF)-κB in sciatic nerves was measured. The behavioral data confirmed that VPN induced by IR leads to hindpaw mechano-allodynia and heat hyperalgesia as well as impaired hindpaw grip strength, indicating the development of neuropathic pain and debilitating symptoms of VPN. The molecular data revealed that VPN induced by IR activated ER stress sensors and effector molecules as well as NF-κB in the sciatic nerves, indicating the involvement of ER stress and NF-κB-mediated neuroinflammation. Notably, 4-PBA significantly reduced the expression of all these markers and improved all behavioral changes induced by IR. This study demonstrated that ER stress and NF-κB-mediated neuroinflammation contribute to VPN induced by IR and that 4-PBA has protective potential against neuropathic pain associated with VPN.

Antinociceptive activity of Copaifera officinalis Jacq. L oil and kaurenoic acid in mice Abstract Copaifera officinalis L. possesses traditional uses as an analgesic, anti-inflammatory, and antiseptic. However, until now the antinociceptive effect and the mechanism of action were not described for Copaifera officinalis L. oil and no compound present in this oil was identified to be responsible for its biological effects. The goal of this study was to identify the presence of kaurenoic acid in Copaifera officinalis oil and investigate its antinociceptive effect, mechanism of action, and possible adverse effects in mice. The quantification of kaurenoic acid in Copaifera officinalis oil was done by HPLC–DAD technique. Male and female albino Swiss mice (25–35 g) were used to test the antinociceptive effect of Copaifera officinalis (10 mg/kg, intragastric) or kaurenoic acid (1 mg/kg) in the tail-flick test, intraplantar injection of capsaicin, allyl isothiocyanate (AITC) or complete Freund’s adjuvant (CFA). Copaifera officinalis oil and kaurenoic acid caused the antinociceptive effect in the tail-flick test in a dose-dependent manner, and their effect was reversed by naloxone (an opioid antagonist). Copaifera officinalis oil or kaurenoic acid reduced the nociception caused by capsaicin or AITC and produced an anti-allodynic effect in the CFA model (after acute or repeated administration for 7 days). Possible adverse effects were also observed, and non-detectable adverse effect was observed for the intragastric administration of Copaiba officinalis oil or kaurenoic acid and in the same way, the treatments were neither genotoxic nor mutagenic at the doses tested. Thus, Copaiba officinalis oil, and kaurenoic acid possess antinociceptive action without adverse effects.

Natural lavender oil ( Lavandula angustifolia ) exerts cardioprotective effects against myocardial infarction by targeting inflammation and oxidative stress Abstract Background The study was conducted to examine therapeutic effects of lavender oil (LO) against myocardial infarction (MI) and its potential mechanisms. Methods A rat model of MI was established and LO (100, 200 and 300 mg/kg) was intraperitoneally administrated immediately after ischemia. Anti-inflammatory and antioxidant activity of LO were evaluated by immunohistochemical assay and measurement of SOD, GSH, and MDA. The myocardial injury markers, apoptotic activity and infarct volume were examined by ELISA, TUNEL and TTC staining, respectively. Results Compared with the control I/R-Vehicle, the expression of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) significantly reduced 8 h after reperfusion and expression of interleukin-10 (IL-10) elevated 48 h after reperfusion in LO-treated rats (P < 0.05). Likewise, significant decreases in apoptotic activity, infarct volume and significant restoration of antioxidant endogenous defenses were observed in LO-treated rats (P < 0.05). Conclusion Collectively, these findings confirm that LO can be a good candidate to reduce injury after MI.

Inhibitory effects of Clematis orientalis aqueous ethanol extract and fractions on inflammatory markers in complete Freund's adjuvant-induced arthritis in Sprague–Dawley rats Abstract Clematis orientalis Linn has long been used as ethnopharmacy for the treatment of arthritis. This study is intended to evaluate the curative efficacy of Clematis orientalis in treating polyarthritis in rats. Aqueous ethanolic extract and fractions (hexane, butanol and aqueous) were administered orally at 200 mg/kg for 28 days after CFA immunization. Paw swelling, paw diameter, arthritic score, body weight, hematological parameters, radiographic and histological analysis of ankle joints were evaluated. Moreover, levels of various inflammatory markers through RT-PCR and ELISA were measured. DPPH and reducing power assays were used to appraise antioxidant capacity. Qualitative phytochemical analysis, determination of total phenolic and flavonoid contents were also carried out. Aqueous ethanolic extract and fractions significantly (p < 0.001) reduced paw volume, paw thickness and arthritic score and considerably prevented decrease in body weight along with anomalous alterations in hematological parameters in comparison with arthritic control. X-ray and histological examination revealed no significant structural changes in ankle joints of treated rats. Expression levels of IL-1β, TNF-α, IL-6, COX-2 and NF-Kβ were significantly (p < 0.05–0.001) suppressed as well as noteworthy increase in the levels of IL-4 and IL-10 among treated animals has been detected. Overproduction of TNF-α and PGE2 was substantially prevented in animals given different treatments. Aqueous ethanol extract and its fractions demonstrated significant and concentration-dependent antioxidant potential. In general, among fractions aqueous fraction exhibited a greater anti-arthritic effect. Phytochemical analysis of aqueous fraction confirmed the presence of flavonoids and glycosides, 215.29 mgGAE/ml phenolic content and 633.03 μgQE/ml flavonoid content. Thus, we suggest Clematis orientalis as a potent strategy for the treatment of rheumatoid arthritis.

Antipyretic effect of phytol, possibly via 5KIR-dependent COX-2 inhibition pathway Abstract Aims This study is aimed at the evaluation of antipyretic effect of PHY in yeast-induced hyperthermia rats. Additionally, possible mechanism of antipyretic action of PHY has been also studied by molecular docking study. Methods Adult male Wistar albino rats were treated with PHY at 100, 150 and 200 mg/kg in 0.05% Tween-80 dissolved in 0.9% NaCl solution. PHY was also given at 200 mg/kg with ibuprofen (IBU) 12.5 mg/kg (p.o.) or paracetamol (PARA) 100 mg/kg (p.o.) to see the combined effect of PHY in animals. In silico study of PHY was performed against cyclooxygenase (COX) enzymes (COX-1 and -2) proteins. Results PHY exhibited the antipyretic effect in febrile rats in a dose and time dependent manner. PHY 200 mg/kg co-treated with IBU12.5 or PARA100 exhibited greater antipyretic effect than the PHY or NSAIDs individual groups. Data from the computational study reveal that 5KIR of COX-2 is the most efficient receptor protein to which PHY interacts. Conclusion PHY attributed an antipyretic effect, possibly via 5KIR-dependent COX-2 inhibition pathway.

Saponins of Tribulus terrestris attenuated neuropathic pain induced with vincristine through central and peripheral mechanism Abstract The study comprises exploring the effects of saponins from Tribulus terrestris (TT) in attenuating the neuropathic pain caused by vincristine (100 μg/ml i.p.) for 10 days (in two 5 day cycles with 2 days pause). Mechanical hyperalgesia and allodynia were assessed by Randall–Sellitto and electronic von Frey tests, respectively. Chemical- induced nociception was assessed by formalin test. Neurophysiological effect of the extract was evaluated by recording sciatic functional index (SFI) on the test days (7, 10, 14, and 21) and sciatic nerve conduction velocity test (SNCV) on the last day. Inflammatory mediators (TNF-α, IL-1β, and IL-6) in both sciatic nerve and brain and brain neurotransmitters, glutamate and aspartate, were measured to support the behavioral response. The saponins of TT-treated group were found to be effective in the behavioral experiments, implying its activity both centrally and peripherally in attenuating pain. The inflammatory mediators in both sciatic nerve and brain (TNF-α, IL-1β, and IL-6) were found to be attenuated with TT saponin treatment in comparison to vincristine-treated group, indicating its anti-inflammatory property. The excitatory neurotransmitters, l-glutamic acid and l-aspartic acid, were also found to be attenuated with TT saponins, implying restoration of neuronal damage and synaptic activity caused by high amount of glutamate due to excess TNF-α in brain and reversing the nociceptive threshold lowered due to aspartate. Thus, TT(S) is peripherally and centrally active in lowering the inflammatory mediators, reversing the neuronal damage and increasing the nociceptive threshold caused due to peripheral neuropathy.

Rutin inhibits carfilzomib-induced oxidative stress and inflammation via the NOS-mediated NF-κB signaling pathway Abstract Background Carfilzomib (CFZ), a proteasome inhibitor approved by the FDA to treat multiple myeloma, may cause nephrotoxicity. Hypothesis Rutin is a bioflavonoid with antioxidant properties. We aimed to examine whether rutin protects the kidney from CFZ-induced nephrotoxicity. Study design This study aimed to demonstrate the effect of rutin on CFZ-induced renal injury via the inhibition of oxidative stress and inflammation. Methods Wistar albino rats were divided into six groups (n = 6): Group 1 (normal control; NC) was administered normal saline for 3 weeks; Group 2 (CFZ/toxic group) received CFZ [4 mg/kg, intraperitoneal (i.p.) injection] twice weekly for 3 weeks; Group 3 (standard treatment group) was administered CFZ (4 mg/kg, i.p.) and olmesartan (2 mg/kg, p.o.) for 3 weeks; Group 4 was administered CFZ (4 mg/kg, i.p.) and rutin (10 mg/kg, p.o.) for 3 weeks; Group 5 was administered CFZ (4 mg/kg, i.p.) and rutin (20 mg/kg, p.o.) for 3 weeks; and Group 6 was administered CFZ (4 mg/kg, i.p.) and rutin (40 mg/kg, p.o.) for 3 weeks. We carried out haematological and biochemical analyses, determined oxidative stress, caspase-3 activity, and protein levels, and performed a histopathological evaluation to confirm CFZ-induced nephrotoxicity and its prevention by rutin administration. Results Exposure to only CFZ significantly (p < 0.05) increased white blood cell (WBC) count, Hb%, and HTC% concentration; however, these features were significantly decreased (p < 0.05) when olmesartan and rutin were administered. CFZ administration significantly decreased (p < 0.0001) the level of antioxidant enzymes; whereas, administration of olmesartan and rutin significantly reversed (p < 0.05) their levels toward the normal range. The levels of caspase-3 enzyme significantly increased (p < 0.001) in the CFZ group and were reduced toward the normal values by olmesartan and rutin administration. Furthermore, the results of NOS-2, NF-κB, IkBa, and IL-17 protein estimation and the histopathological evaluation strengthened our findings that rutin exhibits a protective effect against CFZ-induced nephrotoxicity. Conclusion These findings clearly demonstrate that rutin ameliorates CFZ-induced oxidative stress and inflammation in nephrotoxicity via the NOS-mediated NF-κB signaling pathway.

Dexamethasone inhibits cytokine production in PBMC from systemic sclerosis patients Abstract Glucocorticoids (GC) are widely used in the treatment of SSc, although there is not much evidence to prove the benefits offered by these drugs in this disease. In this study, we evaluated the effects of a GC on cytokine production in peripheral blood mononuclear cells (PBMC) of SSc patients. The effect of dexamethasone (DEX) was evaluated in PBMC of 21 SSc patients and 10 healthy volunteers after stimulation of cells with anti-CD3 and anti-CD28. Cytokines IL-2, IL-4, IL-6, IL-10, IL-17A, IL-17F, IFN-γ, TNF, and IL-1β were quantified in the culture supernatant by CBA or ELISA. Of the patients evaluated in this study, 8 (38%) were taking corticosteroids, and esophageal dysfunction was more frequent in these patients when compared to those who did not take corticosteroids. DEX (1.000 nM) treatment in PBMC of SSc patients stimulated with anti-CD3 and anti-CD28 promoted a significant reduction in IL-2, IL-4, IL-6, IL-10, IL-17A, IFN-γ, TNF, IL-1β (p < 0.001 for all), and IL-17F (p = 0.023) cytokines levels. We did not observe differences in response to in vitro treatment with DEX between groups of patients taking or not taking corticosteroids. In PBMC from healthy volunteers, we observed that DEX treatment significantly reduced IL-4, IFN-γ (p = 0.003 for both), IL-6, IL-10, IL-17A, and TNF (p = 0.002 for all) cytokines. These results show that DEX treatment in PBMC of SSc patients reduced the production of important cytokines involved in the pathogenesis of the disease, suggesting a possible mechanism of action of the CG in the treatment of SSc.

Ginsenoside compound-K inhibits the activity of B cells through inducing IgD-B cell receptor endocytosis in mice with collagen-induced arthritis Abstract Previously, ginsenoside metabolite compound K (C-K) was able to reduce B cell proliferation and serum anti-type II collagen (anti-CII) antibody to normal levels in mice with collagen-induced arthritis (CIA); however, the mechanism by which C-K restores B cell balance is unclear. In the present work, C-K treatment not only alleviated the polyarthritis index, swollen joint count, pathological scores of spleen and joints, spleen index, B cell proliferation and the level of serum antibodies (IgG1, IgG2a and anti-collagen II), but C-K treatment also restored B cell subsets including regulatory B cells, plasma cells, memory B cells, mature B cells, and follicular B cells in CIA mice. Interestingly, C-K did not change the expression level of immunoglobulin D-type B-cell receptor (IgD-BCR) but promoted IgD-BCR endocytosis. C-K treatment enhanced β-arrestin1 expression, facilitating the colocalization between IgD and β-arrestin1, as well as colocalization between IgD and adaptor protein 2 (AP2). Inhibition of the β-arrestin1-AP2 interaction with barbadin significantly reduced the ability of C-K to attenuate IgD-BCR plasma membrane localization. These results taken together depict that C-K ameliorates CIA in part by inhibiting B cell activation through the triggering of IgD-BCR internalization in a β-arrestin1-AP2 dependent manner.