Open Access Original Research Article

Nonglycine Residues in Proteins should most likely have an Allowed Conformation with a Negative Value for Backbone Torsion Angle ɸ

M. A. Basharov

Annual Research & Review in Biology, Page 1-17
DOI: 10.9734/ARRB/2017/36163

Backbone torsion angles ɸ, ψ of a vast majority of nonglycine residues in proteins lay within the peculiar insulated regions in the (ɸ,ψ) space assigned to the conformations allowed for nonglycine residues that embrace the conformations with negative and positive values of ɸ separately. Emphasizing this feature here, the abilities of nonglycine residues to access and reside in the allowed conformations with negative and positive value of angle ɸ evaluated from the alanine dipeptide U(ɸ,ψ) potential energy surface map computations. Established that for nonglycine residues the lowest energy conformation with negative value of ɸ is noticeably favorable than that with positive ɸ and these conformations are separated by unusually higher activation barrier. The occurrences of the residues in the conformations with negative and positive ɸ in a large set of high resolution structures from the Protein Data Bank also investigated. Taken together, the results suggested that nonglycine residues in proteins should most likely have an allowed conformation with negative value of angle ɸ . Residues with positive ɸ angle are considered as outliers with a dubious conformation and should be inspected thoroughly for coordinate errors.

Open Access Original Research Article

Pyretheroids Resistance and Detoxifying Enzymes Activities of Malaria Vector (Anopheles gambiae) Breeding in Auyo Irrigation and Residential Sites, Jigawa State, Nigeria

M. Safiyanu, A. J. Alhassan, A. A. Imam, H. Abdullahi

Annual Research & Review in Biology, Page 1-8
DOI: 10.9734/ARRB/2017/36025

Aims: The aim of this study is to evaluate the resistance status and detoxification enzymes activities of important malaria vector (Anopheles gambae) to WHO recommended pyretheroids insecticides in a highly malaria endemic country like Nigeria.

Study Design: Mosquitoes larvae collected from Auyo residential (AR), and Auyo irrigation (AI) sites were reared to adults and adult gambae were specifically exposed to Permethrin and Deltamethrin. The insecticides resistant and susceptible mosquitoes of AR and AI were respectively redistributed as ARr, ARs, AIr, and AIs.

Place and Duration of Study: Residential site (AR) and Rice irrigation sites (AI) of Auyo town, in Auyo LGA Jigawa State Nigeria, between July and October, 2014.

Methodology: Pyretheroids resistance status was studied using WHO adult mosquito bioassay protocols. Specific activities of insecticides detoxifying enzymes; GST, esterase and monooxygenase of the resistant and susceptible vectors were determined using standard methods.

Results: The results of the study established high resistant status of malaria vectors to both insecticides tested based on WHO interpretation (< 90% mortality). Significant elevated activities (P<0.05) of GST, esterase and lower activity of monooxygenase was recorded in permethrin resistant strain compared to susceptible strain of Auyo irrigation sites. Also a significant higher (P<0.05) activities of GST, esterase and monooxygenase was established in Deltamethrin resistant strain of both AR and AI, except for esterase in AR.

Conclusion: The findings of the study established resistance in both residential and irrigation sites, which could be associated to indiscriminate use of insecticides in residential sites against malarial vector and other flying insects as well as agrochemicals in the irrigation sites. Based on this finding it may be concluded that selection pressure that confers resistance to malarial vector is not restricted to agricultural activities alone.

Open Access Original Research Article

Study of -141 DRD2 Dopamine Receptor Gene Polymorphism (rs1799732) and Heroin Dependence

L. Mehdizadeh Fanid, M. Adampourezare, P. Sistani

Annual Research & Review in Biology, Page 1-5
DOI: 10.9734/ARRB/2017/36287

Previous studies showed that the dopamine receptor D2 (DRD2) may be associated with drug dependence. This study aimed to determine the role of DRD2 in development of substance dependence in Iranian-Azeri heroin-dependent patients.

Materials and Methods: 160 heroin-dependent subjects and 164 healthy controls were recruited in the North West region of Iran. The single-nucleotide-polymorphisms (SNP) of the DRD2 gene were genotyped in all subjects by PCR-RFLP technique and the data analysis was performed through statistical package for the social sciences software, using Chi-square (X2) test.

Results: No significant difference was detected in genotypes and alleles of -141 Ins/Del (rs1799732) polymorphism of DRD2 gene between the control and case groups (p-value>0.05).

Conclusions: The results showed that -141 DRD2 gene polymorphism did not relate with heroin dependence in Iranian-Azeri population.

Open Access Original Research Article

Induction of Mitochondrial-Mediated Apoptosis by Solvent Fractions of Methanol Extract of Heliotropium indicum in Rat Liver Cells

Adeola O. Olowofolahan, Yemisi D. Adeoye, Olufunso O. Olorunsogo

Annual Research & Review in Biology, Page 1-15
DOI: 10.9734/ARRB/2017/36334

Aim: Mitochondrial Membrane Permeability Transition (MMPT) pore has emerged as a promising target for drug development because the release of cytochrome c upon the opening of the pore is a point of no return for mitochondrial-mediated apoptosis to occur. Heliotropium indicum (HI) is as an anti-tumor and wound healing agent in traditional medicine. It is not known whether its mode of action involves the induction of apoptosis via the opening of the MMPT pore.

Methodology: Mitochondria, isolated from male albino rat liver (about 100 g), were exposed to varying concentrations (10, 30, 50, 70, and 90 µg/ml) of  solvent fractions of  methanol extract of HI  i.e  Chloroform (CFHI), Ethylacetate (EFHI), Methanol (MFHI)  and crude  Methanol Extract (MEHI) of HI. Opening of the pore, cytochrome c release, mitochondrial ATPase activity and extent of mitochondrial lipid peroxidation were assessed spectrophotometrically in vitro. Activation of caspases 9 and 3 were also assessed using ELISA kits.

Results: In the absence of Ca2+, CFHI, EFHI, MFHI and MEHI induced the opening of the pore in a concentration-dependent manner with CFHI having the highest induction fold of 26 and MFHI as the lowest having 6.6. All the fractions inhibited lipid peroxidation in a concentration-dependent manner. Also, these fractions induced the release of cytochrome c with CFHI having the highest effect and the least by MFHI. Mitochondrial ATPase activity was enhanced by all the fractions with CFHI having the highest stimulatory effect. Interestingly, intra-peritoneal administration of CFHI and MEHI at 2, 5, 10 and 20 mg/kg body weight for 21 days resulted in significant opening of the pore, the release of cytochrome c and activation of caspases 9 and 3. All these effects were highest with 20 mg/kg body weight.

Conclusion: These findings therefore suggest that Chloroform Fraction of Heliotropium indicum is the most potent of all these fractions and therefore contains the bioactive agent that induces mitochondrial-mediated apoptosis in normal liver cells. The fraction will therefore be useful for further studies for drug development in diseases requesting up-regulation of apoptosis.

Open Access Original Research Article

Characterization and Anti-diabetic Activity of Dihydrophenantherene Isolated from Khaya senegalensis Stem Bark

A. J. Alhassan, I. U. Muhammad, M. S. Sule, A. M. Wudil, A. A. Imam, A. Idi, A. Muhammad, A. Mohammed, I. Alexander, A. Nasir

Annual Research & Review in Biology, Page 1-17
DOI: 10.9734/ARRB/2017/35908

Khaya senegalensis A. Juss (Meliaceae), is regarded as the most popular medicinal meliaceous plant. The present study was conducted to evaluate anti-diabetic potentials of column chromatography fractions (FI-FVII) from ethyl acetate extract of Khaya senegalensis stem bark and detect the bioactive compounds present in the fractions using spectroscopic techniques. Anti-diabetic potential of the fractions (FI-FVII) were tested at dose of 50 mg/kg on wistar albino rats. Fraction (VI) and metformin treated diabetic groups showed significant decrease in fasting blood glucose (FBS), ameliorate hepatic and renal damages by decreasing the level of AST, ALT, ALP, Urea and creatinine compared to untreated diabetic rats and stimulate insulin secretion by β cells. After alloxan administration, the levels of hepatic and renal tissues antioxidant enzymes such as glutathione peroxidase (Gpx), superoxide dismutase (SOD) and catalase (CAT) were decreased whereas the level of hepatic and renal tissues lipid peroxidation (LPO) was elevated. The levels of these antioxidant enzymes were also brought to normalcy by Fraction (VI). Histological studies supported the biochemical findings, and treatment with Fraction (VI) was found to be effective in restoring alloxan-induced pancreatic toxicity in rats. FTIR, GCMS and NMR analysis was conducted for the detection of bioactive compound(s) in Fraction (VI), and the result revealed the presence of methyl 6-ethenyl-7-hydroxy-7,8-dihydrophenanthrene-2-carboxylate. The study concludes that; the anti-diabetic property of Khaya senegalensis stem bark is mediated by the bioactive compound "methyl 6-ethenyl-7-hydroxy-7,8-dihydrophenanthrene-2-carboxylate" through its antioxidant properties and stimulation of damaged pancreas to produce more insulin.