Speaker Biography

Arshad Islam

Dr. Arshad Islam, currently a postdoctoral research fellow at Universidade Federal de Minas Gerais – Brazil, has experience in inorganic chemistry, biological chemistry, medicinal  chemistry,  nano-biotechnology  and  molecular  biology.  He  has  been  working  on  various  research  projects  including  synthesis  and  characterization  of organometallic complexes, nanosystems, metal nanoparticles and their evaluation in in vitro and in vivo experimental models of leishmaniasis, cancer, bacterial infection and Chagas disease and also their interaction with various biomolecules involved in different metabolic pathways. He has published 7 scientific articles in international scientific journals of high impact and a book chapter.  Dr. Islam has presented his research in several national and international conferences


 In  an  effort  to  further  investigate  the  potential  of  organoantimony(V) and organobismuth(V) complexes as antileishmanial agents, we report here new complexes with benzoic acid derivatives, their interaction with DNA,  cytotoxicity  and  activities  against  amastigotes  and  Sb-sensitive and  -resistant  promastigotes  from  different  Leishmania  species.  Four complexes  of  the  Ph3M(L)2  type  were  synthesized  and  characterized, where  M=  Sb(V) or Bi(V) and  L=  deprotonated  ligand  of sodium  salt of 3-(dimethylamino)benzoic acid (HL1) or 2-acetylbenzoic acid (HL2). The  crystal  and  molecular  structures  of  the  complexes  with  L1  were determined  by  single  crystal  X-ray  diffraction.  An  interaction  was demonstrated      between      pX145      plasmid      DNA      and      both organoantimony(V)  and  organobismuth(V),  their  complexes  and  the inorganic  Sb(III).  Ph3Sb(L1)2   and  Ph3Sb(L2)2   were  active  against  L. amazonensis   and   L.   infantum   promastigotes   and   intramacrophagic amastigotes in the range of 3.6-18 µM and showed selectivity index in the range of 2.1-3.9. Ph3Bi(L1)2  was more active against promastigotes (1.2-2.5 µM) than intramacrophagic amastigotes (3.8-11 µM), whereas Ph3Bi(L2)2   was  inactive  against  the  amastigote  form.  Ph3Sb(L1)2   and Ph3Bi(L1)2  showed  no  cross-resistance  with  inorganic  Sb(III)  in  resistant MRPA-overexpressing L. amazonensis and AQP1-mutated L. guyanensis lines.   Cytometric   analysis   using   propidium   iodide   exhibited   that Ph3Sb(L1)2     and   Ph3Bi(L1)2     were   able   to   permeate   the   cellular membrane. Our data taken altogether support the model of different mechanism  of  action  and  uptake  pathway  in  Leishmania  for  these organometallic   complexes,   when   compared   to   the   conventional inorganic antimonial drugs.