Can a combination of glutathione and granulocyte –colony stimulating factor increase chemoprotection?
S Gad El-Hak, I El-Shawaf, E Ali, M Salama
S Gad El-Hak, I El-Shawaf, E Ali, M Salama. Can a combination of glutathione and granulocyte –colony stimulating factor increase chemoprotection?. The Internet Journal of Aesthetic and Antiaging Medicine. 2007 Volume 1 Number 1.
5-FU is a chemotherapeutic agent with myelosuppressive effects, glutathione has been proved to have aprotective action against this myelosuppression. Also granulocyte colony stimulating factor is well known to be a protective agent aginst chemotherapeutics induced bone marrow depression. Whether glutathione (GSH) and granulocyte colony stimulating factor (G-CSF) combination offered more protection on myelosuppression induced by 5-fluorouracil (5-FU) or not was questioned in female mice. The animals were divided into seven groups (10 mice each) . Group 1 received no treatment , group 2 received GSH, group 3 received G-CSF, Group 4 received a single dose of 5-FU, Group 5 received GSH+5-FU, Group 6 received G-CSF + 5-FU and group 7 received daily doses of both GSH and G-CSF + 5-FU. Animals were sacrificed on day 9 i.e. 1 day after 5-FU administration and were evaluated using complete blood count. Surprisingly combination of GSH and G-CSF nullified the protective effects of each other.
5-fluorouracil (5-FU), is an antimetabolite, anticancer agent which is used as an essential part for the treatment of wide range of solid tumors. It has antitumor activity against epithelial malignancies arising in the gastrointestinal tract , breast as well as the head and neck
The haemopoietic growth factor ( granulocyte-colony stimulating factor G-CSF) was proved to shorten the duration and decrease the severity of chemotherapy induced neutropenia (
The aim of the present study was to evaluate the effect of combining both GSH and G-CSF on their chemoprotective functions.
Material and Methods
The study was carried out on 70 adult female mice with their weight ranged 27-32 gm obtained from the Animal House of Mansoura Faculty of Pharmacy. Mice were chosen all females to alleviate the gender effect on the results (
Group 1 of animals (10 mice) received no treatment and served as control group , group 2 (10 mice) received GSH (800 mg/kg) by intraperitoneal route in daily doses for the first 7, and group 3 (10 mice) received G-CSF (250 µg/kg) by subcutaneous route in daily doses for the first 7 days. Group 4 (10 mice) received a single dose of 5-FU (160 mg/kg) by intraperitoneal route in the 8th day , Group 5 (10 mice) received GSH in daily doses (800 mg/kg by intraperitoneal route) for the first 7 days followed by a single dose of 5-FU (160 mg/kg by intraperitoneal route) in the 8th day , Group 6 (10 mice) received G-CSF in daily doses (250 µg/kg by subcutaneous route) for the first 7 days followed by a single dose of 5-FU (160 mg/kg by intraperitoneal route) in the 8th day and group 7 of animals (10 mice) received daily doses of both GSH (800 mg/kg by intraperitoneal route) and G-CSF (250 µg/kg by subcutaneous route) for the first 7 days followed by a single dose of 5-FU (160 mg/kg by intraperitoneal route) in the 8th day. Animals were sacrificed on day 9 i.e. 1 day after 5-FU administration.
Blood samples (2ml, each) were collected in EDTA tubes from the mice cut throats after sacrification. The following haematological values were determined ; haemoglobin (Hb) g/dl , mean corpuscular haemoglobin concentration (MCHC) g/dl , mean corpuscular volume (MCV) Fl (femoliter) , mean corpuscular haemoglobin (MCH) Pcg (pictogram) measured according to the method of
Statistical analysis of data was done by using Excel program (Office 2000) and SPSS (Statistical Package of Social Science) , Windows 98, computer compatible IBM.
The first part of data analysis was descriptive. The mean ± S.D. were used for description of frequency.
The second part of the analysis was analytic: For quantitative data. Student's t test was used for comparison between two groups.
As regards TLC and bone marrow cytology it was found that groups 3 ( received G-CSF ), and 6 (received G-CSF before 5-FU and killed 1 day later) have higher (i.e. better) values than the control, while other groups have lower values ( i.e. worse ). TLC was higher also in group 5 (received GSH before 5-FU and killed 1 day later) than the control. The peripheral leukopenia and medullary myelosuppression in this study are detected in mice received 5-FU either alone or with pretreatment of combined GSH and G-CSF. (Table 2)
When comparing TLC and bone marrow cytology, groups 5 (GSH +5-FU) and 6 (G-CSF + 5-FU) were significantly higher than group 4 (5-FU only). Also both groups were significantly higher than group 7 (GSH+G-CSF+ 5-FU).
Group 7 showed no significant difference with group 4 regarding TLC and bone marrow cytology, but showed significantly lower counts than groups 5 and 6 (Table 3).
5-fluorouracil has been used for the treatment of cancer for more than 40 years and is the most commonly prescribed chemotherapeutic agent (
Glutathione is a naturally occurring endogenous antioxidant that is cytoprotective. Thus, treatment with glutathione or its precursors may protect normal cells during cancer chemotherapy
Priming has been defined as the administration of a colony stimulating factor prior to chemotherapy. There are several theoretical reasons why this schedule of administration may prove to be advantageous (
However, the combined pretreatment with GSH and G-CSF reveal no protection at all denoted by presence of leucopenia in tested group.
These results could be explained by the work of
Despite the previous works it may be the first time to test these results in vivo instead of cellular level.
It can be concluded from this work that the chemoprotective effect of GSH and G-CSF is diminished if they are combined during treatment. So, some times one plus one does not equal two but instead a big zero.