Shail K. Sharma

Interleukin-6-mediated autocrine growth promotion in human glioblastoma multiforme cell line U87MG.

Abstract: Human glioblastoma multiforme cell lines, brain tumor biopsy tissue, and normal human fetal brain synthesize interleukin (IL)‐6 and IL‐6 receptor (IL‐6R). Neither of these is expressed in human neurons or neuroblastoma cell lines in culture. Astrocytes from fetal brain grown in culture retain the ability to synthesize IL‐6 but do not express IL‐6R as inferred from RT‐PCR and Southern blot studies. Coexpression of IL‐6 and IL‐6R in the glioblastoma cell line U87MG is confirmed by immunofluorescence staining. Both specific monoclonal antibodies against IL‐6 and IL‐6R and antisense oligonucleotide to IL‐6 mRNA inhibit the growth of U87MG cells in culture, suggesting the existence of a functional autocrine growth loop. Anti‐IL‐6 antibodies also inhibit the growth of glioblastoma cell lines U373 and U118. The expression of IL‐6 by human fetal astrocytes in culture is highly suggestive of its role as an oncofetal protein responsible for rapid proliferation of fetal and tumor cells but not cells of adult brain.

Megadoses of vitamin C prevent the development of tolerance and physical dependence on morphine in mice.

In mice ascorbate, when co-administered with morphine, suppresses the development of tolerance and physical dependence on the drug, without significantly affecting its analgesic properties as inferred from unaltered ED50 values. The duration of morphine-induced analgesia, however, is progressively reduced with an increase in the amounts of ascorbate. Ascorbate at 1g/kg body weight does not alter the pH of blood, and has no effect on the levels of lipid-peroxides in blood and brain. Studies presented in this paper suggest the potential use of ascorbate in the prevention of development of tolerance in therapeutic applications of narcotics as analgesics. Cultured Neuroblastoma X Glioma hybrid cells (NG 108-15) respond to opiates in two different ways. The rapid receptor mediated inhibition of adenylate cyclase is followed by a long-lived compensatory increase in its activity (1-4). In a recent report (5) we have shown that ascorbate suppresses the delayed etorphine-induced compensatory increase in cAMP levels in NG 108-15 cells without affecting the short-term inhibitory response of cells to the drug. It has been suggested that while the former may be the basis of narcotic dependence and tolerance, the latter is responsible for the analgesic effect. These observations, based on a model system, prompted us to examine the effect of ascorbate on the pharmacological properties of morphine at the organismal level.

Monoclonal antibody to the δ opioid receptor acts as an agonist in dual regulation of adenylate cyclase in NG108-15 cells

Monoclonal antibodies generated against multiple antigenic peptides of the N‐terminal sequence (3LVPSARAELQSSPLV17) of the cloned δ opioid receptor immunoprecipitated a 58 kDa protein from CHAPS‐solubilized NG108‐15 membranes. The immunoprecipitates bound [3H]DPDPE – but not [3H]DAMGO – with a K d of 6.4 nM and a B max of 75 pM. Western blot analysis revealed a distinct band of 58 kDa. The antibodies inhibited basal and PGE1‐stimulated cAMP levels, and mimicked the effect of agonists manifest in a compensatory increase in cAMP formation. The antibody will be potentially useful in the analysis of functional epitopes on the δ opioid receptor.

Phase II clinical trial with Praneem polyherbal tablets for assessment of their efficacy in symptomatic women with abnormal vaginal discharge (an ICMR task force study)

Abnormal vaginal discharge syndrome (AVDS) is a commonly observed gynaecological complaint for which women seek medical attention. The present study was conducted in six Indian Council of Medical Research centres with Praneem polyherbal tablets (PPT), to determine their efficacy in the treatment of symptomatic women with AVDS. Data are given on 141 subjects investigated. In total, 137 women (97%) reported complete (n=62, 44%) and partial (n=75, 53%) relief from symptoms after use of PPT for seven consecutive days. On speculum examination, 71 (74%) women were confirmed to be cured of AVDS. Microbiological tests could only be conducted microscopically for Trichomonas vaginalis, Candida albicans and bacterial vaginosis. It was observed that all women with T. vaginalis had this infection cured by PPT, and the cure rate was 77% for C. albicans and 68% for bacterial vaginosis. Seventy-eight women (55%) reported a transient burning sensation, mostly on the first 2 d of intake of PPT; however, they continued to use the tablets for the prescribed 7 d. This study lays the basis for an extended Phase II/III clinical trial, preferably randomized and comparing a larger number of women to confirm the safety and efficacy of PPT.

Activities of Glycolytic Enzymes in Rapidly Proliferating and Differentiated C6 Glioma Cells

Comparisons of glycolytic enzymes between rapidly proliferating and Bt2 cAMP-induced differentiated C6 glioma cells have been made. Rapidly proliferating cells had higher concentrations of glucose-6-phosphate, fructose-6-phosphate and fructose-1,6-bisphosphate compared to morphologically differentiated cells. Under maximally activating conditions, the specific activity and Vmax of hexokinase and phosphofructokinase enzymes were reduced by approximately 3- and 28-fold, respectively, in differentiated cells, without any change in Km values. These results suggest that hexokinase and phosphofructokinase occupy special control positions and the rate of glycolysis is correlated with cellular proliferation of C6 glioma cells.

Uptake of Liposomally Entrapped Adenosine-3′-5′-Cyclic Monophosphate in Mouse Brain

Abstract[3H] Adenosine-3′,5′-cyclic monophosphate (cAMP) could be entrapped efficiently into small unilamellar vesicles when bound to cAMP-dependent protein kinase. The leakage of [3H]cAMP protein kinase complex from liposomes was reduced by more than 60% as compared to free [3H]cAMP. Hyperosmolar mannitol increased the delivery of liposomally entrapped [3H]cAMP protein kinase to the brain with maximum uptake occurring at 10 min after mannitol administration. Optimal delivery to the brain was observed when vesicles composed of total brain lipids or phosphatidylcholine:cholesterol:sulfatides (7:2:1) were used. A slower clearance of liposomally entrapped material from brain tissue was seen under hyperosmolar conditions.

Action of cyclic 3':5'-AMP on phosphorylation of uridine in ovariectomised rat uterus

Cold trichloroacetic acid-soluble fraction from ovariectomised rat uteri incubated in vitro in enriched medium with or without cyclic AMP has been analysed. No change was observed in the intracellular concentrations of uridine. However, UMP, UDP and UTP concentrations were raised. Cyclic AMP stimulated the phosphorylation of uridine in intact and in cell-free uterine extracts.

Mode of binding of the antithyroid drug propylthiouracil to mammalian haem peroxidases

The article by Singh et al. [(2015), Acta Cryst. F71, 304–310] is retracted.

A device for transplantation of single cells.

A device with a high degree of precision is described for the transplantation of single identified cells in specified regions of the host brain. It consists of two co-centric micropipettes where the inner pipette, functioning as a plunger, is used to drive the cells contained near the tip of the outer pipette into the host. The use of a pre-calibrated micrometer to control the movement of the inner pipette obviates the need of visual monitoring for successful transplantation.

Protein growth factor(s) from C6 glioma cells that promote the growth of murine hybridomas.

C6 glioma cell conditioned medium (C6CM) has been used as a growth supplement for murine hybridomas. At 10% C6CM has been found to increase cell proliferation by 3-4-fold. This effect is observed in the presence of saturating concentration of FCS. Clonal growth is also enhanced 6.7-fold. No growth promoting effect is seen on murine myelomas or spleen cells. The factor(s) appear to be protein in nature.