A Comparative in-vitro study between the interaction of aqueous extracts of Ephedra, Nepeta, and Hymenocrater with histone proteins

Background and Aim: Ephedra, Nepeta, and Hymenocrater herbs have long been used in the treatment of many diseases, but their interactions with cellular components, especially nuclear proteins, are still unknown. On the other hand, in the eukaryotic cell nucleus histone proteins play a main role in the packaging of the genetic material as chromatin. The present study aimed at comparing the in-vitro interactions of aqueous extracts of Ephedra, Nepeta, and Hymonocarater with histone proteins. Materials and Methods: Histone proteins type 2A were purchased from Sigma company and aqueous extract of Ephedra, Nepeta and Hymenocrater were prepared in the research laboratory of Birjand University of Medical sciences. Different concentrations of the aqueous extracts were incubated with histone proteins, then analyzed by UV-Spectroscopy and Circular dichroism. Results: Aqueous extract of Nepeta increased maximum absorbance of histone proteins at 210 nm, but the reduction in absorbance was shown at its high concentration. The absorbance of histone proteins also changed in the presence of the aqueous extract of Ephedra and Hymenocrater and it decreased to zero at higher concentration of Ephedra. Circular Dichroism studies demonstrated that the structure of histone proteins changed in the presence of mentioned aqueous extract; the observed effect of the aqueous extract of ephedra was higher than Nepeta and Hymenocrater. Conclusion: The aqueous extracts of ephedra, Nepeta,and Hymenocrated interacted with histone proteins and changed their structure. The effect of ephedra was higher than others

Mutational and bioinformatics analysis of the NKX2.1 gene in a cohort of Iranian pediatric patients with congenital hypothyroidism (CH)

Abstract Congenital hypothyroidism (CH) occurs with a relatively alarming prevalence in infants, and if not diagnosed and treated in time, it can have devastating consequences for the development of the nervous system. CH is associated with genetic changes in several genes that encode transcription factors responsible for thyroid development, including mutations in the NK2 homeobox 1 (NKX2.1) gene, which encodes the thyroid transcription factor-1 (TTF-1). Although CH is frequently observed in pediatric populations, there is still a limited understanding of the genetic factors and molecular mechanisms contributing to this disease. The sequence of the NKX2.1 gene was investigated in 75 pediatric patients with CH by polymerase chain reaction (PCR), single-stranded conformation polymorphism (SSCP), and direct DNA sequencing. Four missense heterozygous variations were identified in exon 3 of the NKX2.1 gene, including three novel missense variations, namely c.708A>G, p.Gln202Arg; c.713T>G, p.Tyr204Asp; c.833T>G, p.Tyr244Asp, and a previously reported variant rs781133468 (c.772C>G, p.His223Gln). Importantly, these variations occur in highly conserved residues of the TTF-1 DNA-binding domain and were predicted by bioinformatics analysis to alter the protein structure, with a probable alteration in the protein function. These results indicate that nucleotide changes in the NKX2.1 gene may contribute to CH pathogenesis