ABSTRACT
Concerns about the social and economic collapse, high mortality rates, and stress on the healthcare system are developing due to the coronavirus onslaught in the form of various species and their variants. In the recent past, infections brought on by coronaviruses severe acute respiratory syndrome coronaviruses (SARS-CoV and SARS-CoV-2) as well as middle east respiratory syndrome coronavirus (MERS-CoV) have been reported. There is a severe lack of medications to treat various coronavirus types including MERS-CoV which is hazard to public health due to its ability for pandemic spread by human-to-human transmission. Here, we utilized sinapic acid (SA) against papain-like protease (PLpro), a crucial enzyme involved in MERS-CoV replication, because phytomedicine derived from nature has less well-known negative effects. The thermal shift assay (TSA) was used in the current study to determine whether the drug interact with the recombinant MERS-CoV PLpro. Also, inhibition assay was conducted as the hydrolysis of fluorogenic peptide from the Z-RLRGG-AMC-peptide bond in the presence of SA to determine the level of inhibition of the MERS-CoV PLpro. To study the structural binding efficiency Autodock Vina was used to dock SA to the MERS-CoV PLpro and results were analyzed using PyMOL and Maestro Schrödinger programs. Our results show a convincing interaction between SA and the MERS protease, as SA reduced MERS-CoV PLpro in a dose-dependent way IC50 values of 68.58 µM (of SA). The TSA showed SA raised temperature of melting to 54.61 °C near IC50 and at approximately 2X IC50 concentration (111.5 µM) the Tm for SA + MERS-CoV PLpro was 59.72 °C. SA was docked to MERS-CoV PLpro to identify the binding site. SA bound to the blocking loop (BL2) region of MERS-CoV PLpro interacts with F268, E272, V275, and P249 residues of MERS-CoV PLpro. The effectiveness of protease inhibitors against MERS-CoV has been established and SA is already known for broad range biological activity including antiviral properties; it can be a suitable candidate for anti-MERS-CoV treatment.
ABSTRACT
The complicated multiple sclerosis (MS) can exhibit subacute sight deterioration and can lead to total deprivation of vision. In the current work, we explored the therapeutic outcome of Cathepsin B inhibitor (CA-074) against retinopathy and optic neuritis (ON) caused by experimental autoimmune encephalomyelitis (EAE) induced by proteolipid protein peptide (PLP) in female SJL/J mice. A daily dose of 10 mg/kg CA-074 was administered to the EAE mice intraperitoneally for 14 days from day 14 post-immunization until day 28. The Western blot and immunofluorescence analyses show inflammation in the optic nerve through the elevation of iNOS and NFkB markers in EAE mice. Optic neuritis was reported which is a consequence of demyelination and axon injury, estimated with the reduction in myelin basic protein (MBP). The glial fibrillary acidic protein (GFAP) expression level was found to be elevated in the retina of EAE mice which confirmed the retinopathy. The administration of CA-074 ameliorated optic neuritis and retinopathy by reducing inflammation. The treatment with CA-074 also reduced the demyelination and axonal injuries in the EAE mice. The findings of this study have shown the protective effect of CA-074 in the case of retinopathy and ON inflicted by EAE in SJL/J mice.
ABSTRACT
Euphorbia hirta L. (Euphorbiaceae) (E. hirta) is a tree locally used as a traditional medicine in Africa and Australia to treat numerous diseases such as hypertension, respiratory ailments, tumors, antipyretic, anti-inflammatory activities. In the present study, we investigated the anti-arthritic activity of fresh leaves of E. hirta ethanol extract that was found to inhibit the production of inflammatory mediators and cytokines of adjuvant arthritis in rats. Adjuvant arthritis was induced in rats (Wistar) by the subplantar injection of 0.05 ml freshly prepared suspension (5.0 mg/ml) of steam killed Mycobacterium tuberculli in liquid paraffin. Animals were treated with graded doses of 25, 50, 100 and 200 mg/kg of E. hirta ethanol extract, p.o. E. hirta significantly inhibited the swelling of the adjuvant-induced arthritis. Moreover, E. hirta at higher dose (200 mg/kg) showed 40.54 ± 1.09 % of CD3+, 15.1 ± 0.76 % of CD4+, 12.2 ± 1.18 % of CD8+ T cell receptor and 17.6 ± 1.11 % gated of CD19+ B cell receptor revealing a down regulation of adjuvant-induced arthritis as compared to the corresponding valves of the arthritic control rats. According to the results shown in Tables 1, 2, the production of IL-1ß, TNF-α, IL-2 and IFN-γ were increased in splenocytes of arthritic rats and this increased level was reduced by E. hirta. Also, E. hirta significantly down regulated lipopolysaccharide (LPS)-induced production of nitric oxide production in peritoneal macrophages. These results suggest that E. hirta exhibits an improvement in adjuvant-induced arthritis through down regulation of activated macrophages and T lymphocytes functions. Such unique effects of E. hirta shown on adjuvant arthritis rat model may be advantageous to the long-term treatment of clinical rheumatoid arthritis. Table 1 Effect of E. hirta and prednisolone (Pred) on LPS-induced IL-1ß and TNF-α productions from splenocytes in Mycobacterium tuberculli-induced inflammatory arthritic rats Treatment Dose (mg/kg) IL-1ß (pg/ml) TNF-α (pg/ml) Arthritic control (AC) - 323.56 ± 31.65 180.91 ± 24.12 E. hirta 25 311.19 ± 29.08* 171.43 ± 22.54* E. hirta 50 287.12 ± 26.98* 164.54 ± 21.76** E. hirta 100 243.12 ± 19.21*** 157.30 ± 18.54*** E. hirta 200 215.21 ± 16.05*** 138.43 ± 17.98*** Prednisolone (Pred) 5 187.18 ± 15.21*** 123.77 ± 15.12*** Normal control (NC) - 54.12 ± 12.54 71.94 ± 12.12 Each value indicates the mean ± SEM of six animals AC arthritic control, NC normal control; E. hirta (25, 50, 100 and 200 mg/kg) and prednisolone (5 mg/kg) were given p.o. from day 0 to day 21 after Mycobacterium tuberculli injection, respectively * p < 0.05; ** p < 0.01; *** p < 0.001, compared to arthritic control Table 2 Effect of E. hirta and Prednisolone (Pred) on Con A-induced IL-2 and IFN-γ productions from splenocytes in Mycobacterium tuberculli-induced inflammatory arthritic rats Treatment Dose (mg/kg) IL-2 (pg/ml) IFN-γ (pg/ml) Arthritic control (AC) - 235.98 ± 15.23 165.95 ± 13.87 E. hirta 25 225.12 ± 14.76** 154.76 ± 11.07** E. hirta 50 207.76 ± 13.87** 134.76 ± 11.01** E. hirta 100 189.98 ± 12.65 *** 110.64 ± 10.98*** E. hirta 200 157.84 ± 14.32 *** 98.54 ± 10.76*** Prednisolone (Pred) 5 131.08 ± 13.31*** 87.65 ± 10.61*** Normal control (NC) - 78.12 ± 12.04 31.87 ± 10.12 Each value indicates the mean ± SEM of six animals AC arthritic control, NC normal control; E. hirta (25, 50, 100 and 200 mg/kg) and prednisolone (5 mg/kg) were given p.o. from day 0 to day 21 after Mycobacterium tuberculli injection, respectively * p < 0.05; ** p < 0.01; *** p < 0.001, compared to arthritic control.
