Sidney Belman

The fluorimetric determination of formaldehyde

Abstract A sensitive fluorimetric procedure for formaldehyde has been developed. The method, which can measure 0.01 μg formaldehyde, is based on the Hantzsch reaction between acetylacetone, ammonia, and formaldehyde. The product, 3,5-diacetyl-I,4-dihydrolutidine, is colored yellow and fluoresces yellow green. Infra-red spectra indicate that this compound is ionic in dilute solution and aggregated in concentrated solution. The Hantzsch reaction may be extended for the assay of other aldehydes, amines, and β-diketones.

Inhibition of DMBA‐induced mouse skin tumorigenesis by garlic oil and inhibition of two tumor‐promotion stages by garlic and onion oils

A single 2-mg dose of garlic oil applied 30 minutes before a single carcinogenic dose of 7,12-dimethylbenz[a]-anthracene (DMBA) inhibited papilloma production in Sencar mice. The three groups were controls (Group 1), garlic oil applied 30 minutes before DMBA (Group 2), and garlic oil applied 30 minutes after DMBA (Group 3). The percents of mice with papillomas at 20 weeks were 94, 72, and 79, respectively. The decreases in Groups 2 and 3 were significant. The number of papillomas per mouse was 4.2 +/- 0.5 (Group 1), 2.3 +/- 0.8 (Group 2), and 3.4 +/- 0.6 (Group 3). The decrease in Group 2 was significant. A single 5-mg dose of garlic oil maximally inhibited DMBA-induced epidermal DNA synthesis by 86% when applied two hours before the carcinogen. Two-stage promotion in DMBA-initiated Sencar mice was achieved by twice-weekly applications of 8.5 nmol of 12-O-tetradecanoylphorbol-13-acetate (TPA) for 2 weeks followed by twice-weekly applications of 8.5 nmol of mezerein for 18 weeks. The oils were applied 30 minutes after each promotion by TPA or mezerein. Single doses of 1 mg onion or garlic oil inhibited the first and second stages of promotion. The groups used were control (Group 1), garlic oil applied after stage 1 (Group 2), onion oil applied after stage 1 (Group 3), propenyl sulfide applied after stage 1 (Group 4), garlic oil applied after stage 2 (Group 5), onion oil applied after stage 2 (Group 6), and propenyl sulfide applied after stage 2 (Group 7). The percent of mice with papillomas was significantly decreased by all agents in Groups 2-7. The data are 81, 83, 91, 68, 96, and 86, respectively. The number of papillomas per mouse was significantly reduced by onion and garlic oils but not by propenyl sulfide. The data are 9.4 +/- 0.8, 6.3 +/- 0.7, 7.4 +/- 0.5, 9.2 +/- 1.2, 3.7 +/- 0.9, 6.2 +/- 0.6, and 9.1 +/- 1.4 for Groups 1-7, respectively. Onion and garlic oils inhibited the TPA-stimulated DNA synthesis when given as single doses of 5 mg one hour before TPA. The inhibition by garlic oil was most effective when given one hour before TPA but was evident when given from two hours before to two hours after TPA. These results, and those of others (AS Sadhana, Cancer Lett, 40, 193-197, 1988), who obtained inhibition of initiation, indicate that onion and garlic oils inhibit all stages of mouse skin tumorigenesis.(ABSTRACT TRUNCATED AT 400 WORDS)

Effects of multiple phorbol myristate acetate treatments on cyclic nucleotide levels in mouse epidermis.

Abstract The basal levels of 3′,5′ adenosine monophosphate and 3′,5′ guanosine monophosphate were measured in mouse epidermis after initiation with 7,12 dimethylbenzanthracene and 1,2,10 or 20 skin treatments with the tumor promoter phorbol myristate acetate. Slight but significant decreases in cAMP and dramatic (5–10 fold) increases in cGMP were found after multiple treatments with the promoter. The cyclic nucleotide levels found in isolated solid tumors closely paralleled these changes.

Papilloma and carcinoma production in DMBA-initiated, onion oil-promoted mouse skin.

Groups of 20 females Ha/ICR mice were initiated with 25 micrograms 7,12-dimethylbenz[a]anthracene (DMBA) and promoted one week later with topical treatments three times per week of 5 micrograms phorbol myristate acetate (PMA) and/or onion oil or garlic oil. Promotion was continued for 49 weeks in most experiments. Promotion was continued for 60 weeks in the experiment that evaluated the effect of time intervals between PMA and garlic oil. All experiments were conducted with 0.2 ml acetone solutions of agents. Onion oil, but not garlic oil, was a weak promoter in mouse skin. A 1-mg dose produced five papillomas in three mice and one carcinoma in 330 days (18 survivors). The 10-mg dose was more effective; it produced cumulative yields of 56 papillomas in 14 mice and 7 carcinomas in 4 mice in 345 days (14 survivors). Onion oil is neither an initiator nor a whole carcinogen. The effects of intervals between PMA and a 1-mg dose of onion or garlic oil were determined. These intervals were -2 hrs, -1 hr, -0.5 hr, +0.5 hr, +1 hr, and +2 hrs with respect to time of PMA application. Maximal inhibition of papillomas by onion oil was observed at the +0.5-hr interval and was similar to that previously reported. Garlic oil is not a promoter. It inhibited papillomas at the +0.5-hr, +1.0-hr, and +2.0-hr intervals but did not appear to affect carcinoma production.

Proteases and Cyclic Nucleotides

Recent symposia and reviews (1–8) have attributed to proteases a significant role in regulation of physiological functions. Aside from the well-known function of general protein degradation, they also produce limited proteolysis which converts zymogens to active enzymes by the hydrolysis of a single peptide bond or of several bonds by sequential action. Much work over the past 10–15 years has been directed at the determination of a specific role for proteases in the regulation of normal cell growth, the functions of specialized cells, and in the control of tumor development, growth and metastases. The presence of a variety of protease inhibitors with varying types of specificity in plasma and cells of many tissues (8) points to a fine control of physiological functions for proteases.

Stimulation of cell growth and proliferation in NIH-3T3 cells by onion and garlic oils

Onion and garlic oil were seen to shorten the cell-doubling time and stimulate the growth and proliferation of NIHY-3T3 cells. FNollowing treatment with either onion or garlic oil, an increase in the growth rate and almost a 2-fold increase in cell number over the control was observed within a 24-hour period. Phorbol myristate acetate when given simultaneously with either oil appeared to nullify both effects. FNollowing exposure to low doses (< 10 µm/ml) of either oil, an increase in cell survival, not seen with the oil control tricaprylin, was observed following a 5-day exposure period. At higher concentrations cell survival decreased proportionately in all cases. The appearance of multinucleated cells, which increased with dose and time, was also observed following treatment with both garlic and onion oil.

Decreased β-adrenergic responsiveness in mouse epidermal papillomas during tumor promotion with phorbol myristate acetate

Abstract The response to the β-adrenergic agonist (−)-isoproterenol in mouse epidermis and in papillomas arising during tumor promotion with phorbol myristate acetate was determined by measurement of cyclic AMP levels after in vivo administration of (−)-isoproterenol. Papillomas exhibited less than half the hormonal responsiveness found in epidermis from control groups or from papilloma-bearing animals. No difference in the incorporation of labelled (−)-isoproterenol into epidermal or papilloma tissue was seen.

2-Amino-1,4-Naphthoquinone, an Oxidation Product of 2-Amino-1-Naphthol.∗

Summary The carcinogenic metabolite, 2-amino-1-naphthol, of the bladder carcinogen 2-naphthylamine was air oxidized at pH 7.2 to produce many products separable by thin layer chromatography. The ether extract contained one major product which was identified as 2-amino-1,4-naphthoquinone.

THE EFFECTS OF CIS-RETINOIC ACID ON SCANNING ELECTRON MICROGRAPHS OF BLADDERS FROM RATS FED 0.03% FANFT

Male Fischer 344 rats were fed 0.03% N[4-(5-nitro-2-furyl)-2-thiazole] formamide (FANFT) and FANFT + 13- cis -retinoic acid. The bladders were examined by scanning electron microscopy every month for 6 months. FANFT induced hyperplastic changes which increased with time. These changes included appearance of cobblestone cells and uniform microvilli. A dramatic change occurred in 6 months when all cells were hyperplastic and bore numerous microvilli. At least half the cells had pleomorphic microvilli, a possible marker for neoplasia. 13- cis -Retinoic acid inhibited all these changes. At 6 months, very few cells had pleomorphic microvilli.