title: Studying inhibition of calcium oxalate stone formation: an in vitro approach for screening hydrogen sulfide and its metabolites.
abstract: OBJECTIVE
  Calcium oxalate urolithiasis is one of the most common urinary tract diseases and is of high prevalence. The present study proposes to evaluate the antilithiatic property of hydrogen sulfide and its metabolites like thiosulfate & sulfate in an in vitro model.
  
  
  METHODS
  The antilithiatic activity of sodium hydrogen sulfide (NaSH), sodium thiosulfate (Na(2)S(2)O(3)) and sodium sulfate (Na(2)SO(4)) on the kinetics of calcium oxalate crystal formation was investigated both in physiological buffer and in urine from normal and recurrent stone forming volunteers. The stones were characterized by optical and spectroscopic techniques.
  
  
  RESULTS
  The stones were characterized to be monoclinic, prismatic and bipyramidal habit which is of calcium monohydrate and dihydrate nature. The FTIR displayed fingerprint corresponding to calcium oxalate in the control while in NaSH treated, S=O vibrations were visible in the spectrum. The order of percentage inhibition was NaSH>Na(2)S(2)O(3)>Na(2)SO(4).
  
  
  CONCLUSIONS
  Our study indicates that sodium hydrogen sulfide and its metabolite thiosulfate are inhibitors of calcium oxalate stone agglomeration which makes them unstable both in physiological buffer and in urine. This effect is attributed to pH changes and complexing of calcium by S(2)O(3)(2)-and SO(4)(2)- moiety produced by the test compounds.
authors.affiliation: School of Chemical and Biotechnology, SASTRA University, Thanjavur, T. N, India.|Vascular Biology Lab, SASTRA University, Thanjavur, T. N, India.
authors.forename: S
authors.initials: S
authors.lastname: Vaitheeswari
authors.affiliation: School of Chemical and Biotechnology, SASTRA University, Thanjavur, T. N, India.|Vascular Biology Lab, SASTRA University, Thanjavur, T. N, India.
authors.forename: R
authors.initials: R
authors.lastname: Sriram
authors.affiliation: School of Chemical and Biotechnology, SASTRA University, Thanjavur, T. N, India.|Vascular Biology Lab, SASTRA University, Thanjavur, T. N, India.
authors.forename: P
authors.initials: P
authors.lastname: Brindha
authors.affiliation: School of Chemical and Biotechnology, SASTRA University, Thanjavur, T. N, India.|Vascular Biology Lab, SASTRA University, Thanjavur, T. N, India.
authors.forename: Gino A
authors.initials: GA
authors.lastname: Kurian
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D002129:Calcium Oxalate / Q000737:chemistry / Q000378:metabolism*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D006862:Hydrogen Sulfide / Q000737:chemistry* / Q000378:metabolism*; D008297:Male; D015203:Reproducibility of Results; D017550:Spectroscopy, Fourier Transform Infrared; D014556:Urine / Q000737:chemistry; D052878:Urolithiasis / Q000378:metabolism* / Q000517:prevention & control*
chemical_list: D002129:Calcium Oxalate; D006862:Hydrogen Sulfide