1.Novel Piperine compound AB05 (N-5-(3,4-dimethoxyphenyl) -2E,4E pentadienylpiperidine) inhibits H1N1 influenza virus propagation in vitro
Mohammed, A. ; Velu, A.B. ; Al-Hakami, A.M. ; Meenakshisundaram, B. ; Esther, P. ; Abdelwahid, S.A. ; Irfan, A. ; Prasanna, R. ; Anantharam, D. ; Harish, C.C.
Tropical Biomedicine 2020;37(No.4):1062-1073
Pandemic H1N1 influenza virus respiratory illness has become an inevitable global
health concern. With antigenic drift, it becomes necessary to have drugs over tailor-made
HIN1 vaccine every year. In the current study, we screened many Piperine derivative in
which, N-5-(3,4-dimethoxyphenyl)-2E,4E-pentadienylpiperidine (AB05) and was further studied
for anti-H1N1influenza virus activity and compared with other stains in-vitro on MDCK cell
line. Initial cytotoxic doses of AB05 for the MDCK cell line were > 25µM. The results showed
a dose-dependent reduction of the viral plaque’s in the adsorption assay with EC50 of 0.33 µM.
The mechanism of AB05 was by inhibition of matured viral release as evaluated by the time
of virus addition with incubation of 6-10 hours. With the promising H1N1 virucidal activity of
AB05, we included various strains of human influenza virus to screen AB05 inhibition of
Neuraminidase (NA). The result showed 70% NA inhibition in WSN (H1N1), 90% in H3N2 &
Influenza B and 49% in Tamiflu resistant H1N1). Further our In silco docking studies
substantiated experimental results by showing the difference in binding and cooperation
between H1N1 and N3N2. Together these observations illustrate that Piperine derivative
AB05 is a promising lead molecule which needs further evaluation in animal models.
2.Zika virus antibody-positivity among symptomatic/asymptomatic pregnant women in the Aseer region displays pre-exposure to dengue viruses
Harish, C.C. ; Ayed, A.A. ; Alhanshani, A.A. ; Youssef, A.A. ; Esther, P. ; Riyad, A.A.M. ; Abdullah, M.A. ; Anandalakshmi, S. ; Ashish, K. ; Ahmed, M.A.H.
Tropical Biomedicine 2023;40(No.3):337-343
Antibody cross-reactivity among flaviviruses is a major limitation in understanding the prevalence
without vector control measures. In this study, we investigated the presence of Zika virus (ZIKV)-specific
antibodies and the significance of their cross-reactivity with other flaviviruses, which could affect the
serological specificity in both symptomatic and asymptomatic pregnant women. Among the results
obtained from 217 serum samples tested for ZIKV-specific IgM and IgG, no specific predictions regarding
seropositivity or exposure due to extensive cross-reactivity with dengue virus (DENV) serology could be
made. Clear-cut positivity was observed in 1.8% (n = 4) and 1.0% (n = 2) for ZIKV IgM and IgG, respectively.
The same samples assessed for DENV showed 1.3% (n = 3) seropositivity each for IgM and IgG levels.
None of the samples were positive for ZIKV and DENV IgM or IgG. However, one sample (0.4%) tested
positive for ZIKV and DENV IgM. No significant correlation was observed between DENV IgM and IgG
when comparing the overlapped serotiters. On the other hand, the ZIKV IgG-positive sample showed
higher serotiters for DENV IgG, indicating cross-reactivity with ZIKV but without statistical significance.
Therefore, screening for the incidence of ZIKV becomes particularly challenging in a population where
the presence or pre-exposure to DENV is observed. Our observations further suggest that unless
flavivirus prevalence is properly addressed, determining the prevalence of ZIKV antibodies, which may
be confounded with other uninvestigated flaviviruses, will be complicated.