Intake of garlic and its bioactive components.

The health benefits of garlic likely arise from a wide variety of components, possibly working synergistically. The complex chemistry of garlic makes it plausible that variations in processing can yield quite different preparations. Highly unstable thiosulfinates, such as allicin, disappear during processing and are quickly transformed into a variety of organosulfur components. The efficacy and safety of these preparations in preparing dietary supplements based on garlic are also contingent on the processing methods employed. Although there are many garlic supplements commercially available, they fall into one of four categories, i.e., dehydrated garlic powder, garlic oil, garlic oil macerate and aged garlic extract (AGE). Garlic and garlic supplements are consumed in many cultures for their hypolipidemic, antiplatelet and procirculatory effects. In addition to these proclaimed beneficial effects, some garlic preparations also appear to possess hepatoprotective, immune-enhancing, anticancer and chemopreventive activities. Some preparations appear to be antioxidative, whereas others may stimulate oxidation. These additional biological effects attributed to AGE may be due to compounds, such as S-allylcysteine, S-allylmercaptocysteine, N(alpha)-fructosyl arginine and others, formed during the extraction process. Although not all of the active ingredients are known, ample research suggests that several bioavailable components likely contribute to the observed beneficial effects of garlic.

Dietary rosemary suppresses 7,12-dimethylbenz(a)anthracene binding to rat mammary cell DNA.

Commercially available ground rosemary powder was examined for its ability to modify the in vivo binding of 7,12-dimethylbenz(a)anthracene (DMBA) metabolites to mammary cell DNA in 55-d-old rats fed diets containing varying quantities and types of lipids. Supplementing a casein-based diet containing 20% corn oil with 1 % rosemary for 2 wk reduced by 76% the occurrence of DMBA-induced DNA adducts occurring 24 h after treatment with 50 mg DMBA/kg body weight. A comparable reduction in DNA adducts (66%) occurred when 0.5% rosemary was added to a diet containing 20% corn oil, and the quantity of DMBA given was reduced to 25 mg/kg body weight. The reduction in the occurrence of adducts occurring 24 h after DMBA treatment caused by 0.5% dietary rosemary was greater (P < 0.05) when added to a diet containing 20% corn oil than when added to a diet containing 5% corn oil and 15% coconut oil. Rosemary, 1% but not 0.5%, reduced DMBA-induced DNA adducts when the diet contained 5% corn oil. These studies demonstrate that rosemary is effective in reducing the binding of DMBA metabolites to rat mammary cell DNA. Furthermore, the present studies demonstrate that the benefits of rosemary are dependent on the source and concentration of dietary lipids.

Dietary components modify the ability of garlic to suppress 7,12-dimethylbenz(a)anthracene-induced mammary DNA adducts.

Various dietary components were evaluated as factors influencing garlic's ability to depress rat mammary cell DNA adducts resulting from 7,12-dimethylbenz(a)anthracene (DMBA) treatment. Diets with or without garlic powder (20 g/kg) were provided for 2 wk before DMBA treatment (25 mg/kg body weight). Rats fed diets containing 36 g casein/100 g diet had 31% fewer (P < 0.05) mammary cell DNA adducts than those fed 12 g/100 g. Garlic supplementation significantly (P < 0.05) reduced DNA adducts in rats fed either 12 or 36 g casein/100 g by 35 and 32% respectively. In the absence of dietary garlic, DNA adducts were 23% lower (P < 0.05) in rats provided a diet containing supplemental L-methionine at 0.9 g/100 g than at 0.3 g/100 g. However, adduct inhibition by garlic supplementation was greater in rats fed the lower (P < 0.05) amount of methionine (54 vs. 26% inhibition). Adduct levels in rats fed diets with 20 g corn oil/100 g were twice those occurring in rats fed 5 g/100 g (P < 0.05), regardless of adjustment for energy density. Garlic supplementation prevented the increase in DNA adducts caused by increasing dietary corn oil. Combining dietary supplements of garlic, selenite (0.5 mg/kg diet) and retinyl acetate (328 mg/kg diet) inhibited the occurrence of DNA adducts to a greater degree than when each was supplied individually. These studies demonstrate that while dietary garlic can reduce DNA adduct formation in mammary tissue caused by DMBA, this protection is influenced by several dietary components.

Impact of various sources of garlic and their constituents on 7,12-dimethylbenz[a]anthracene binding to mammary cell DNA.

The present studies assessed the impact of various sources of garlic and their constituents (water- and ethanol-extracts and S-allylcysteine) on the in vivo binding of the carcinogen 7,12-dimethylbenz[a]anthracene (DMBA) to rat mammary cell DNA. The provision of dietary raw garlic powder (2%) or its water-extract (1.5%) reduced DMBA-DNA binding by 33 and 46% respectively. Dietary supplementation with a commercially available deodorized garlic powder (powder A) at 2 or 4% depressed the occurrence of adducts by 50 and 78% respectively, while providing a commercially available high sulfur garlic preparation (powder B) at 2% reduced binding by 56%. A pair-feeding study revealed that the depression in carcinogen binding was independent of food intake or weight gain. Although 1% raw garlic powder did not significantly influence the occurrence of DMBA-DNA adducts, an equivalent as the water-extract (0.75%), the ethanol-extract (0.015%) or commercially available powders (A and B) reduced DMBA adducts in mammary tissue by 44, 25, 71 and 65% respectively. Dietary fortification with S-allylcysteine (SAC), a water-soluble constituent of processed garlic, caused a progressive decrease in the binding of DMBA to DNA. Studies with SAC suggest the primary effect of garlic and its constituents is on the bioactivation and binding of the carcinogen rather than DNA repair. These data reveal that several forms of garlic are effective, although variable, in altering carcinogen bioactivation and presumably chemically induced carcinogenesis.

Metastatic adenocarcinoma to the uterine cervix from gastric cancer. A clinicopathologic analysis of 16 cases.

BACKGROUND: Metastatic adenocarcinoma to the uterine cervix from gastric cancer is rare, and the clinicopathologic features of this metastasis are unclear. METHODS: A clinicopathologic review of 16 patients with metastatic adenocarcinoma to the uterine cervix from gastric cancer was performed. RESULTS: The ages of the patients ranged from 29 to 57 years, and 81.3% of the patients were premenopausal. Nine of the patients had undergone gastrectomy previously. In 11 patients the histologic type of the gastric cancer was poorly differentiated adenocarcinoma and, in 5 patients, signet ring cell carcinoma. The cervical metastasis was diagnosed 11-121 months (mean, 57.5 months) after the diagnosis of the gastric cancer in 10 of the patients. In six patients, the cervical metastasis was discovered synchronously or before the diagnosis of the gastric cancer. The colposcopic findings were normal in 57.1%, but 56.3% had abnormal cervical smears. In all patients, tumor cells were present in the dilated lymphatics of the cervix. Metastases to the uterine body and bilateral ovaries were common, and half of the patients had metastases to the paraaortic lymph nodes. Extirpation of the cervix was performed in six patients. The prognosis was poor, regardless of the treatment method. CONCLUSIONS: The route of metastasis to the cervix is surmised to be retrograde lymphatic, and this extension is often slow. Periodic gynecologic examinations should be performed indefinitely for premenopausal female patients with advanced gastric cancer.

Effect of absorption promoters on subcutaneous absorption of human epidermal growth factor in rats.

Subcutaneous administration of human epidermal growth factor (hEGF) to rats gave a significantly smaller value of area under the curve (AUC) of concentration in plasma of immunoreactive hEGF versus time than intravenous administration, probably because the slow entry rate into the blood circulation and consequently the enzymic degradation of hEGF at the injection site. In the present study, absorption promoters such as sodium caprate, N-acylamino acids, disodium ethylenediamine-tetraacetate (EDTA), and sodium glycocholate were used because they were expected to inhibit the enzymic degradation of hEGF at the injection site and to facilitate the entry of hEGF into the blood circulation. Coadministration of an absorption promoter with hEGF significantly increased the entry rate and AUC value of immunoreactive hEGF compared with the case without the absorption promoter. The enzymic degradation of hEGF in the supernatant of the rat subcutaneous tissue homogenates and in the buffer solution containing leucine aminopeptidase or protease was markedly inhibited by the presence of the absorption promoters except EDTA. On the other hand, only EDTA increased the initial entry rate of FITC-dextran (M(r), 4000), which is not metabolized at the injection site, although all absorption promoters including EDTA markedly increased the extravasation of Evans blue. Thus, the increased subcutaneous bioavailability of hEGF in the presence of absorption promoters (except EDTA) was mainly attributed to the inhibitory effect of absorption promoters against the enzymic degradation of hEGF at the subcutaneous tissues.

Enhanced rectal and nasal absorption of human epidermal growth factor by combined use of the absorption promoter and the synthetic polymer in rats.

Previously, the presence of sodium carboxymethylcellulose (CMC Na) in addition to an absorption promoter, sodium caprate (C10 Na), in the dosing solution was found to be necessary for the enhancement of the rectal absorption of human epidermal growth factor (hEGF). In the present study, other synthetic polymers and absorption promoters were examined for their ability to enhance the rectal and nasal absorption of hEGF in rats. The effect of polymers in combined use with 100 mM C10 Na on the rectal absorption of hEGF was in the following order: 1% methylcellulose 1% hydroxypropylmethylcellulose 0.1% polyacrylic acid 1% CMC Na. Other absorption promoters such as N-lauroyl-alanine (C12-A) and dihydroxy-bile salts also enhanced the rectal absorption of hEGF in combined use with CMC Na. In order to confirm the increased rectal absorption of hEGF, the disappearance of hEGF from the rectal loop was examined. When hEGF in a 1% CMC Na solution (200 ug/kg) was administered in the rectal loop, the disappearance percent of hEGF during 60 min was 13.9% of the dose, although hEGF was not detected in the plasma. The presence of promoters such as 10 mM C10 Na or 15 mM C12-A in 1% CMC Na increased the disappearance percent to about 50% in a dosing range of hEGF from 100 to 500 ug/kg. On the other hand, a markedly enhanced nasal absorption of hEGF by 100 mM C10 Na was observed even in the absence of any polymer in a dising solution. However, addition of CMC Na into the dosing solution accelerated the rate of nasal absorption of hEGF in early phase.(ABSTRACT TRUNCATED AT 250 WORDS)

Epidermal growth factor prolongs survival time of tumor-bearing mice.

We observed that human epidermal growth factor (hEGF) alone prolonged the survival time of mice bearing various murine syngeneic tumors as well as athymic nude mice bearing human xenografts. No changes in the subcutaneous solid tumor mass volume were observed. Prolongation of survival time by hEGF was observed in mice bearing murine epidermoid carcinoma (BSC) and human gastric carcinoma (KATO III), but not in murine epidermoid carcinoma (KLN205) or human epidermoid carcinoma (A431). Human tumor cells such as A431, KATO III, and murine tumor cells, KLN205, BSC had roughly 2 X 10(6), 3 X 10(4), 1.3 X 10(3) and 1 X 10(3) EGF receptors/cell, respectively. Although KLN205 and BSC tumor cells maintained nearly the same number of EGF receptors, the effects of hEGF were very different. Although A431 tumor cells had nearly 100 times more receptors than KATO III cells, the prolongation of survival time of mice bearing A431 by hEGF was no better than that of mice bearing KATO III. Accordingly, it appears that this prolongation of survival time by hEGF is independent of the number of EGF receptors on tumor cells. In addition, hEGF was shown to inhibit experimental pulmonary metastasis of murine BSC tumor, but was ineffective with murine KLN205 tumor. These results suggest that prolongation of survival time by hEGF may result from the inhibition of tumor cell metastasis and EGF may play a role in preventing the metastasis of certain malignant neoplasms unrelated to its effects through the EGF receptor on tumor cells.

Response of A431 experimental human solid xenograft to mitomycin C in combination with human epidermal growth factor in mice.

We previously demonstrated that the antitumor efficacy of various antitumor agents such as 5-fluorouracil and cisplatin against experimental solid tumors was enhanced by pre- or simultaneous administration of human epidermal growth factor (hEGF). In the present study, the combined therapy by hEGF and mitomycin C (MMC) as an antitumor agent was studied in A431 solid tumor-bearing mice to determine the dosage schedule of hEGF. When MMC alone was injected intraperitoneally (2 mg/kg) every 7th day to the tumor-bearing mice, tumor weights increased to 2138 +/- 285 mg from 282 +/- 41 mg during 22 d. Tumor weight in every day treatment of hEGF alone for 21 d increased to the same extent in the treatment by MMC alone. On the other hand, the increase of the solid tumor weight in the every day treatment and in the every 7th day treatment of hEGF, in combination with the every 7th day administration of MMC, were as follows; from 282 +/- 41 mg to 1522 +/- 357 mg (71.2 +/- 16.7% of MMC alone) and from 280 +/- 44 mg to 1245 +/- 150 mg (58.2 +/- 7.0% of MMC alone), respectively, demonstrating a greater antitumor potency of MMC in the combination with the every 7th day treatment of hEGF. Both combined therapies did not affect the toxicity of MMC as evaluated by decrease in nontumorous body weight. Single subcutaneous administration of hEGF to A431 tumor-bearing mice caused the decrease of the binding capacity of hEGF to A431 tumor cells by 80% 24 h after the administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Possible mechanism of gastric mucosal protection by epidermal growth factor in rats.

The mechanism of the protection by human epidermal growth factor (hEGF) against the gastric mucosal lesions induced by acidified ethanol was studied in rats. At different times following the subcutaneous administration of hEGF (30 micrograms/kg), intragastric acidified ethanol (EtOH: 0.125 M HC1 = 50:50 v/v%) was administered to induce an experimental gastric mucosal lesion. Mean length of the lesion in the gastric mucosa was used as a lesion index. Extravasation of intravenously injected Evans blue into the gastric wall and gastric contents was used as an indicator of vascular permeability. Pretreatment with hEGF decreased both the gastric mucosal lesions and the increase of vascular permeability caused by acidified ethanol with similar time profiles relative to pretreatment with hEGF. Maximal protective actions of hEGF occurred about 10 to 30 min after the observed peak plasma concentration of hEGF. Indomethacin and N-ethylmaleimide, but not iodoacetamide, blocked the protective action of hEGF, indicating that endogenous prostaglandins and/or sulfhydryls may participate in the protective action of hEGF. The content of endogenous nonprotein sulfhydryls in the gastric mucosa decreased markedly after acidified ethanol. However, pretreated hEGF did not restore the sulfhydryl contents. Thus, it seemed that endogenous prostaglandins, but not sulfhydryls, are the probable mediators for protection against gastric mucosal injury caused by acidified ethanol.

Protective effect of human epidermal growth factor against the experimental gastric mucosal lesions in rats.

The protective effect of human epidermal growth factor (hEGF) on the gastric mucosal lesions in rats was examined in relation to the immunoreactive concentration of plasma. Human EGF (30 micrograms/kg) was administered intravenously, intraperitoneally or subcutaneously. At different times following the administration of hEGF, rats received acidified ethanol solution to induce an experimental gastric mucosal lesion. Sum of lesion length in the gastric mucosa was used as a lesion index. Human EGF administered parenterally markedly decreased the gastric mucosal lesions in 10 min after administration of necrotizing solution, and 10 to 30 min delay was observed in the development of maximal protective action. Profiles of protective potency against the hEGF dose administered intraperitoneally or subcutaneously 30 min before administration of necrotizing solution revealed that the effective dose of hEGF (ED50) was about 5.2 and 2.6 micrograms/kg, for intraperitoneal and subcutaneous administrations, respectively.

Epidermal growth factor receptor-mediated selective cytotoxicity of antitumor agents toward human xenografts and murine syngeneic solid tumors.

Severe toxic side effects of antiproliferative agents limit their clinical usefulness as antitumor drugs. Recently we observed that the antitumor efficacy of various antitumor agents (5-fluorouracil, tegafur, adriamycin, mitomycin C, cyclophosphamide, and cisplatin) against experimental solid tumors was enhanced by prior or simultaneous administration of human epidermal growth factor (EGF). However, coadministration of EGF did not enhance the toxicity of antitumor agents as measured by LD50 and body weight loss. The above selective potentiation of efficacy of the antitumor agents by human EGF can be characterized as follows. In a dose-dependent manner, human EGF enhanced the efficacy of an antitumor agent (5-FU) treatment against human epidermoid carcinoma A431 transplanted sc in athymic nude mice [ED50 = 2.9 (0.2-49.7, 95% confidence interval) microgram/kg, sc]. Various degrees of enhancement were also observed against other experimental tumors transplanted sc. The degrees of enhancement were directly proportional to the numbers of human EGF binding sites present on tumor cell plasma membrane (threshold of binding site density = 1.5 X 10(3) sites/cell) using 5-FU or cisplatin as an antitumor agent, thus suggesting that the binding of EGF to the receptors on tumor cells is an essential process in enhancing the susceptibility of tumor cells to antitumor agents. Normal cells including intestinal epithelial and bone marrow cells are endowed with fewer EGF binding sites (less than 10(3) sites/cell). This may explain partially the absence of EGF-enhanced cytotoxicity by antitumor agents toward normal cells.

Overproduction of a gastrointestinal hormone, secretin, in Escherichia coli cells and its chemical characterization.

A cloned synthetic DNA fragment coding for 27-desamidosecretin (DAS), which differs from natural porcine secretin by the lack of the amide group at the carboxyl-terminal valine residue, was fused to the beta-galactosidase gene (lacZ) at the EcoRI site near the 3'-terminus of the gene. The fusion gene was efficiently expressed in Escherichia coli, yielding 1.15 X 10(6) fused-protein molecules per cell. After the treatment of the fused protein with cyanogen bromide, DAS was purified by a combination of ion-exchange column chromatography and reverse-phase high-performance liquid chromatography (HPLC). The structure of bacterial DAS was confirmed by tryptic mapping and amino acid composition analyses. The bacterial DAS was not amidated at its carboxyl-terminal valine residue. Nevertheless, it stimulated pancreatic secretion in rats as does authentic porcine secretin, indicating that the carboxyl-terminal amide is not essential to secretin activity.

An ultrastructural-cytochemical study on the proliferation of smooth endoplasmic reticulum induced by chlorobiphenyls (PCB) in the guinea pig liver cells.

The ultrastructural changes in the liver cells of guinea pigs induced by the oral administration of PCB were studied by electron microscopy; also electron-microscopic cytochemistry for glucose-6-phosphatase (G-6-Pase) activity was applied. Proliferation of smooth endoplasmic reticulum (sER) was the most prominent change observed in the liver cells, which remained as long as 90 days after the final administration. G-6-Pase activity was ultracytochemically demonstrated not only in the rough and smooth endoplasmic reticulum and the nuclear envelope in the liver cells of normal controls, but also in the proliferated sER in the liver cells of PCB-treated animals. The present investigation revealed that PCB stored in the animal body induced the proliferation of sER in the liver cells for a long time after the cessation of the treatment, and that sER in the liver cells, normally existing or proliferated, always showed positive activity of G-6-Pase.