Radioprotective effect of alk(en)yl thiosulfates derived from allium vegetables against DNA damage caused by X-ray irradiation in cultured cells: antiradiation potential of onions and garlic.

To evaluate a radioprotective effect of sodium n-propyl thiosulfate (NPTS) and sodium 2-propenyl thiosulfate (2PTS) derived from onions and garlic, respectively, rat hepatoma H4IIE cells and mouse lymphoma L5178Y cells were preincubated with each of these compounds for 48 hours at 37°C before receiving 10 Gy of X-ray irradiation. Cell damage caused by the irradiation was quantified as comet tail moment, which represents the degree of DNA damage. X-ray-induced DNA damage was significantly decreased in both H4IIE and L5178Y cells by micromolar concentrations of NPTS and 2PTS compared with the control without the compounds. The protective effect was more potent with 2PTS than NPTS. Onions and garlic have antiradiation potential.

Sodium 2-propenyl thiosulfate derived from garlic induces phase II detoxification enzymes in rat hepatoma H4IIE cells.

There is evidence that onions and garlic protect against cancer in humans. It has been suggested that this effect is partly due to the organosulfur compounds in Allium vegetables and that these substances act through induction of phase II detoxification enzymes. Here, we hypothesized that alk(en)yl thiosulfates, sodium n-propyl thiosulfate (NPTS), and sodium 2-propenyl thiosulfate (2PTS), which were identified in onions and garlic, respectively, may induce phase II enzymes. Therefore, rat hepatoma cells (H4IIE) were cultured with 1 to 100 micromol/L of NPTS or 2PTS for 48 hours at 37 degrees C; and the activities and messenger RNA (mRNA) expression levels of phase II enzymes in H4IIE cells were investigated. The effects of diallyl trisulfide and tert-butylhydroquinone, known as phase II inducers, were also examined as positive controls and compared with the responses of NPTS and 2PTS. Quinone reductase (QR) activity and mRNA expression levels of QR and epoxide hydrolase 1 were significantly increased by 2PTS (P < .05-.005). In particular, QR activity was increased at a relatively low concentration of 2PTS (10 micromol/L). However, glutathione S-transferase activity and mRNA expression levels of glutathione S-transferase A5 and uridine diphosphate glucuronosyl transferase 1A1 were not changed by 2PTS. In contrast, NPTS did not affect the activities and mRNA expression levels of these phase II enzymes. These results show that 2PTS can induce phase II enzymes, and its inductive effect is comparable or superior to that of diallyl trisulfide and tert-butylhydroquinone.

Growth inhibitory effect of alk(en)yl thiosulfates derived from onion and garlic in human immortalized and tumor cell lines.

Two alk(en)yl thiosulfates, sodium n-propyl thiosulfate (NPTS) and sodium 2-propenyl thiosulfate (2PTS), are natural constituents of onion and garlic, respectively, which were identified originally as causative agents of onion- and garlic-induced hemolytic anemia in dogs. As a continuation of our studies on the beneficial functions of NPTS and 2PTS, in the present study, we investigated the antitumor effects of these compounds. They were shown to inhibit the in vitro proliferation of three human tumorigenic cell lines, WiDr, 293 and HL-60, in a dose-dependent manner. Overall, NPTS seemed to have weak activity for inhibiting cell growth compared with 2PTS, though not in WiDr cells, which were sensitive to both compounds. NPTS and 2PTS caused oxidative damage to HL-60 cells and induced apoptosis. The extent of apoptosis was approximately proportional to that of the oxidative damage and also to that of the cytotoxicity caused by these compounds. These results suggest that the alk(en)yl thiosulfates have an antitumor effect through the induction of apoptosis initiated by oxidative stress.

Functional constipation with impaired rectal sensation improved by electrical stimulation therapy: report of a case.

Patients with intractable constipation often complain of social, physical, and psychologic stress. Recently, biofeedback therapy has been widely used for the management of intractable constipation, particularly in cases of constipation associated with pelvic floor dyssynergia. However, some constipated patients often complain of absent or diminished sense of wanting to defecate. It is unclear whether impaired rectal sensation is a cause or outcome of constipation and what specific treatment is available for these patients. We treated a 25-year-old female patient who complained of intractable constipation for ten years. Colon transit time study and defecography showed nonspecific findings. Her anorectal manometric findings were within normal ranges with the exception of impaired rectal sensation. Rectal sensory threshold volumes for desire and urge to defecate and maximal tolerated volume were greatly increased. She was treated by electric stimulation therapy for the purpose of improving impaired rectal sensory function. After 14 sessions of electric stimulation therapy, her constipated symptoms improved dramatically. Furthermore, the desire and urge threshold volumes were remarkably decreased. We report this case of constipation with impaired rectal sensation possibly treated by electric stimulation therapy.

[Clinical factors associated with response to biofeedback therapy for patients with chronic constipation].

BACKGROUND/AIMS: Biofeedback therapy has been widely used for the treatment of constipated patients. However, there are only a few reports about the clinical factors that can predict the effectiveness of biofeedback therapy. The aim of this study was to evaluate prognostic factors before the initiation of biofeedback treatment in constipated patients. METHODS: Biofeedback treatment was performed in 114 patients with constipation. After classifying the patients into two groups, responder and non-responder by subjective and objective parameters, univariate and multivariate analysis were performed to evaluate the factors associated with effectiveness of biofeedback therapy. RESULTS: Eighty-five patients (74.6%) responded to biofeedback therapy. Pre-treatment balloon expulsion test, paradoxical contraction on manometry, defecation index and anal residual pressure during straining were the factors that influenced the results of biofeedback treatment. On multivariate analysis, defecation index (odds ratio=67.5, p<0.05) and paradoxical contraction on manometry (odds ratio=0.053, p<0.05) were the factors that showed significant difference between the responders and non-responders. CONCLUSIONS: This study suggests that several pre-treatment prognostic factors are associated with response to biofeedback for the constipated patients. Using prognostic factors, we may be able to evaluate the patterns of pelvic floor dysfunction and responsiveness of biofeedback therapy for the patients with constipation.

Effect of electrical stimulation in constipated patients with impaired rectal sensation.

BACKGROUND AND AIMS: A subgroup of constipated patients complain of absent or diminished sense of wanting to defecate, suggesting that one of the causes of constipation is impaired rectal sensation. Electrical stimulation therapy (EST) has recently been used to treat patients with urinary and/or fecal incontinence. This study evaluated the efficacy of EST in constipated patients, especially those with impaired rectal sensation. PATIENTS AND METHODS: Of the 130 patients with functional constipation as defined by Rome II criteria, 22 patients who had impaired rectal sensation (rectal desire threshold volume > or =90 ml) on an anorectal manometry were selected. We treated 12 with EST and 10 with biofeedback therapy (BFT) according to a randomized order. RESULTS: Overall symptoms of patients significantly improved after each therapy in both groups. Interestingly, frequency of sense of wanting to defecate improved only after EST. On objective findings there was significant improvement in anal residual pressures on attempted defecation only after BFT solely. On the other hand, rectal sensory threshold volumes for desire and urge to defecate and maximal tolerated volume improved significantly only in the EST group. CONCLUSION: Our findings show that the efficacy of EST can be comparable to BFT in a subgroup of constipated patients, especially those with impaired rectal sensation. EST might be considered as an adjunctive therapeutic modality for the management of functional constipation with impaired rectal sensation.