Appraisal of anti-arthritic potential of Coronopus didymus (L.) Sm. aqueous extract and its safety study in Wistar rats

The current study aimed to find out the anti-arthritic activity and safety study of Coronopus didymus aqueous extract (CDAE) as well as its chemical characterization by HPLC-DAD. Safety study including acute and subacute toxicity studies of the plant aqueous extract was also performed. In complete Freund's adjuvant-induced arthritic model (CFA), 0.15 ml CFA was injected in the left hind paw at day 1 in all rats except normal rats. Treatment with CDAE at 200, 400, and 800 mg/kg and methotrexate (1 mg/kg) was administered at day 8 and continued till 28th day using oral gavage. The CDAE considerably (p < 0.05) reduced the paw swelling and arthritic score, and reinstated the body weight and blood parameters. The CDAE considerably modulated superoxide dismutase, catalase, reduced glutathione, and malondialdehyde level in liver homogenate in contrast to disease control. The CDAE at 400 mg/kg considerably reduced IL-6, IL -1β, COX-2, and NF-ĸβ, whereas elevated IL-10, IL-4, and I-kappa β as equated to disease and standard groups. The LD50 of CDAE > 2000 mg/kg. In subacute toxicity study, CDAE at 200-800 mg/kg did not exhibit clinical signs of toxicity, mortality, hematological, biochemical, and histological alteration in the liver heart, kidney, and lungs in contrast to the normal group. It was concluded that the presence of delphinidine-3-glucoside, diosmetin, 3-feruloyl-4,5-dicaffeoyl quinic acid, and gallic acid in CDAE might be accountable for its anti-arthritic activity and safe use for a long period.

Different mechanisms of arsenic related signaling in cellular proliferation, apoptosis and neo-plastic transformation

Arsenic is a toxic heavy metal vastly dispersed all over the earth crust. It manifests several major adverse health issues to millions of arsenic exposed populations. Arsenic is associated with different types of cancer, cardiovascular disorders, diabetes, hypertension and many other diseases. On the contrary, arsenic (arsenic trioxide, As₂O₃) is used as a chemotherapeutic agent in the treatment of acute promyelocytic leukemia. Balance between arsenic induced cellular proliferations and apoptosis finally decide the outcome of its transformation rate. Arsenic propagates signals via cellular and nuclear pathways depending upon the chemical nature, and metabolic-fates of the arsenical compounds. Arsenic toxicity is propagated via ROS induced stress to DNA-repair mechanism and mitochondrial stability in the cell. ROS induced alteration in p53 regulation and some mitogen/ oncogenic functions determine the transformation outcome influencing cyclin-cdk complexes. Growth factor regulator proteins such as c-Jun, c-fos and c-myc are influenced by chronic arsenic exposure. In this review we have delineated arsenic induced ROS regulations of epidermal growth factor receptor (EGFR), NF-ĸβ, MAP kinase, matrix-metalloproteinases (MMPs). The role of these signaling molecules has been discussed in relation to cellular apoptosis, cellular proliferation and neoplastic transformation. The arsenic stimulated pathways which help in proliferation and neoplastic transformation ultimately resulted in cancer manifestation whereas apoptotic pathways inhibited carcinogenesis. Therapeutic strategies against arsenic should be designed taking into account all these factors.

NF-ĸβ upregulates ADAMTS5 expression by direct binding after TNF-α treatment in OUMS-27 chondrosarcoma cell line

Inflammation caused-aggrecan degradation is a critical event in the pathogenesis of osteoarthritis (OA). The aggrecanases like a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5) are assumed to be key players in the aggrecan destruction. To develop the comprehensive therapy method for OA, it is essential to elucidate the activation mechanism of ADAMTS5 gene after stimulation of inflammatory cytokines like tumor necrosis factor-α (TNF-α). The cell lines of human chondrosarcoma (OUMS-27) and embryonic kidney (HEK293T) were incubated with tumor necrosis factor-α (TNF-α) for certain time periods, and the expression level of ADAMTS5 was measured in both mRNA and protein levels. Tissue-specific ADAMTS5 activation was founded to be induced after TNF-α treatment. Then, the constructs for the promoter region of ADAMTS5 were prepared and luciferase assay was conducted to understand the involvement mechanism of nuclear factor-kappa beta (NF-ĸβ) in ADAMTS5 activation. It was demonstrated that NF-ĸβ induces the ADAMTS5 expression level by directly binding the promoter region of ADAMTS5. Although the TNF-α blocker is used for OA treatment, the development of a more comprehensive treatment strategy is an urgent need. Our experimental data contributes in terms of selecting NF-ĸβ as a target molecule. Up to date, NF-ĸβ has been proven to involve in the ADAMTS5 up-regulation after several pro-inflammatory cytokines stimulation. In conclusion, our findings make important contributions to the knowledge about the roles of NF-ĸβ in ADAMTS5 activation under inflammatory conditions. So, NF-ĸβ could be considered to be a potential target for OA treatment.

Effect of hesperetin on inflammatory and oxidative status in trinitrobenzene sulfonic acid-induced experimental colitis model

In our study, the effect of hesperetin on inflammatory and oxidative status in trinitrobenzene sulfonic acid (TNBS)-induced experimental colitis model was investigated through different methods. Eighteen Wistar albino male rats were divided in to three groups: Group I (Control, n = 8; 1 ml physiological saline), Group II (Colitis, n = 8; 1 ml TNBS), Group III (Hesperetin, n = 8; 1 ml TNBS and 100 mg/kg hesperetin). Macroscopic and microscopic scores were calculated to determine the damage to the colon at the end of the experiment. Serum tumor necrosis factor-α (TNF-α) and tissue interleukin-6 (IL-6) levels were determined using the ELISA method. Myeloperoxidase (MPO), superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) levels were investigated spectrophotometrically. The TUNEL method was used for the detection of apoptotic cells in the colon tissue. Inducible nitric oxide synthase (iNOS) and nuclear factor-kappa-B (NF-ĸβ) expression in the colon were determined immunohistochemically. Hesperetin administration has shown to significantly reduce levels of MPO, MDA, and proinflammatory agents (TNF-α, IL-6, and NF-ĸβ). It has also been proven to inhibit mucosal apoptosis. This study indicates that hesperetin is protective against TNBS-induced colitis model via antiinflammatory, antioxidant and antiapoptotic effects.