Effects of aluminum on erythroidal cells in bone marrow in rats

The study has been carried out on Wistar rats. The aim of the present study was to trace the effect of aluminum on erythroidal cells in bone marrow in rats. The number of proerythroblast after 10 days of experiment with aluminum slowly decreased up to 80 days of experiments. However, the number of basophilic erythroblasts after 10 days insignificantly increased but after 20 days gradually decreased up to 80 days of experiments. The bone marrow polichromatic erythroblasts after 10 days of experiment slightly decreased, however after 20, 40 and 80 days of experiments the values decreased significantly. The quality of orthochromatic erythroblasts after 10 days of experiments dropped and after 20, 40 and 80 days of experiments significantly decreased compared to the control value. Aluminum also brings about histological changes in the bone marrow. The statistical significant reductions of hemoglobin and hematocrit levels were found in the aluminum exposed rats.     

β-Arrestin-biased signaling of PTH analogs of the type 1 parathyroid hormone receptor

Parathyroid hormone (PTH) is an anabolic agent that mediates bone formation through activation of the Gα_s-, Gα_q- and β-arrestin-coupled parathyroid hormone receptor type 1 (PTH1R). Pharmacological evidence based on the effect of PTH(7–34), a PTH derivative that is said to preferentially activate β-arrestin signaling through PTH1R, suggests that PTH1R-activated β-arrestin signaling mediates anabolic effects on bone. Here, we performed a thorough evaluation of PTH(7–34) signaling behaviour using quantitative assays for β-arrestin recruitment, Gα_s- and Gα_q-signaling. We found that PTH(7–34) inhibited PTH-induced cAMP accumulation, but was unable to induce β-arrestin recruitment, PTH1R internalization and ERK1/2 phosphorylation in HEK293, CHO and U2OS cells. Thus, the β-arrestin bias of PTH(7–34) is not apparent in every cell type examined, suggesting that correlating in vivo effects of PTH(7–34) to in vitro pharmacology should be done with caution.     

Effects of yeast extract on the production of phenylpropanoid metabolites in callus culture of purple basil (Ocimum Basilicum L. var purpurascens) and their in-vitro evaluation for antioxidant potential

Ocimum basilicum L. var. purpurascens is an enriched reservoir of pharmaceutically important compounds with plenty of health and therapeutic attributes such as phenolic acids and anthocyanins. However, the inefficient production of aforementioned metabolites in wild has restricted its commercial utilization. Herein, commercially viable phytochemicals have been enhanced through elicitation of in-vitro cultures of O. basilicum using yeast extract.The impact of various concentrations (YE 1 mg/L,YE 10 mg/L, YE 25 mg/L, YE 50 mg/L, YE 100 mg/L, YE 200 mg/L and YE 400 mg/L) of yeast extract on biomass accumulation, phytochemical production, and antioxidant activities were assessed in callus cultures. Moderate concentration of yeast extract (100 mg/L) enhanced biomass accumulation i.e. fresh weight (FW 216.28 g/L) and dry weight (DW 15.49 g/L) up to 1.5 folds as compared to control (FW 167.14 g/L and DW 10.25 g/L). Similarly, yeast extract (100 mg/L) increased total phenolic and flavonoid contents as well as enhanced antioxidant activities such as ABTS (2,2 azinobis 3-ethylbenzthiazoline-6-sulphonic acid), FRAP (ferric reducing antioxidant power) and DPPH (2,2-diphenyl-1-picryhydrazyl). High performance liquid chromatography (HPLC) analysis was elucidated for further phytochemical investigation. HPLC analysis showed an increase of almost 1.9 folds as compared to control in rosmarinic acid (15.19 mg/g DW), chicoric acid (2.13 mg/g DW), peonidin (2.70 mg/g DW) and cyanidin (1.57 mg/g DW). Likewise, 1.8 fold and 2.4 folds increase was observed in eugenol essential oils (0.25 mg/g DW) and chavicol (0.037 mg/g DW), respectively. For cellular antioxidant activity, reactive oxygen specie or reactive nitogen specie (ROS/RNS) was induced in yeast cells and the effect of O. basilicum callus culture was further investigated in stressed yeast cells. A positive correlation exists between the antioxidant activities, TPC and TFC analysis. In short, these results showed that yeast extract could act as an efficient elicitor to enhance pharmacologically important metabolites in callus cultures of Ocimum basilicum.

Graphical abstract

     

Flavonoids of Tinospora malabarica

A dibenzoylethane and an allyloxyflavone isolated from Tinospora malabarica have been assigned the structures 1-(2′,4′-dimethoxyphenyl)-3-(3″     

Selection and characterization of randomly produced mutants of gene V protein of bacteriophage M13.

Gene V protein of bacteriophage Ff (M13, f1, fd) is a master regulator of phage DNA replication and phage mRNA translation. It exerts these two functions by binding to single-stranded viral DNA or to specific sequences in the 5' ends of its target mRNAs, respectively. To study the structure/function relationship of gene V protein, M13 gene V was inserted in a phagemid expression vector and a library of missense and nonsense mutants was constructed by random chemical mutagenesis. Phagemids encoding gene V proteins with decreased biological activities were selected and the nucleotide sequences of their gene V fragments were determined. Furthermore, the mutant proteins were characterized both with respect to their ability to inhibit the production of phagemid DNA transducing particles and their ability to repress the translation of a chimeric lacZ reporter gene whose expression is controlled by the promoter and translational initiation signals of M13 gene II. From the data obtained, it can be deduced that the mechanism by which gene V protein binds to single-stranded DNA differs from the mechanism by which it binds to its target sequence in the gene II mRNA.     

Microtiter plate assay for the measurement of glutathione and glutathione disulfide in large numbers of biological samples

By combining the least complicated and expedient methods of sample handling with the sensitivity and specificity of the GSH assay by enzymatic recycling and the small volumes and software capabilities of microtiter plate technology we have devised a rapid, sensitive, and easy assay for GSH and GSSG in biological samples. The assay is sensitive to 5 pmol in sample volumes of 50 microliters, although other volumes could be used. The use of a computer-driven microplate with software capable of linear kinetic data storage and analysis on each well, Maxline series microplate readers and Softmax software, enables the user not only to assay large numbers of samples per day but also to have immediate calculated results. We suggest by examples that measurements of total GSH as well as changes in GSH:GSSG in vitro and in vivo are feasible with this technology.     

The effect of aluminium upon the activity of selected bone marrow enzymes in rats.

This study was carried out on male Wistar rats. The bone marrow activities of acetylcholinesterase (AchE-EC.3.1.1.7.), glutathione reductase (GR-EC.1.6.4.2.) and glucose-6-phosphate dehydrogenase (G6PD-EC.1.1.1.49.) were determined as affected by aluminium. The present experiments have revealed that within the first days there will be an increase in enzyme activity in the bone marrow. Simultaneously a decline in the activity of bone marrow could be observed which occurred later in the first course of the experiment.