Hematopoietic effects of Azadirachta indica methanolic extract in cyclophosphamide mediated myelosuppressed albino rat.

Myelosuppression or bone marrow suppression is one of the most common side effects caused by anti-cancer drugs. Certain nonsteroidal anti-inflammatory drugs (NSAIDs), antibiotics and viruses like B19 virus can also cause bone marrow suppression resulting in serious consequences like leukopenia, anemia and thrombocytopenia. Currently, it is mainly treated by Filgrastim, use of which is not without side effects. Certain natural drugs can be a safer alternative to treat myelosuppression. Azadirachta indica, commonly known as Neem, is an important medicinal plant of subcontinent. Keeping in view the traditional uses of Neem, present study aims to investigate its potential role in reversing myelosuppression. Albino rats were used to determine hematopoietic activity of Neem leaves after inducing myelosuppression by cyclophosphamide given subcutaneously. Filgrastim was used as reference standard to compare the antimyelosuppressant activity of the drug. The drug was evaluated in three doses i.e. 50mg/kg, 100mg/kg and 200mg/kg body weight, while blood samples were drawn on 0, 1st, 7th, 14th and 21st day. The drug was found to be effective in reversing bone marrow suppression in all three doses based on the hematological parameters (mean WBC, RBC, platelets, Hb, Hct etc.) which improved significantly. The results suggest that the drug can be used as antimyelosuppressant after establishing its safety and identifying its active constituents with their mechanism of action.

Identification of vitamin D and other bone metabolism parameters as risk factors for primary bone marrow oedema syndrome.

BACKGROUND: The aetiology and pathogenesis of primary bone marrow oedema syndrome (BMES) remain unclear. This retrospective cross-sectional study in a large cohort of patients with BMES was performed to characterise the overall skeletal status and turnover in patients with BMES, with the aim of identifying risk factors for this disease. METHODS: Patients who were diagnosed with BMES on the basis of clinical and radiological (magnetic resonance imaging) findings in our outpatient clinic were identified retrospectively. Patient history, co-existing metabolic disorders, bone metabolism parameters (serum calcium, phosphate, 25-OH-D3, bone-specific alkaline phosphatase, parathyroid hormone, and osteocalcin, and urinary deoxypyridinoline) and bone mineral density (as measured by dual-energy X-ray absorptiometry) were extracted from the medical records. Patients with secondary causes for BMES were excluded from the study. RESULTS: Of the 171 patients, 65 were identified without secondary cause for BMES. Of the 65 patients, 61.5% were female. The mean age was 49.5 ± 16.7 years, and age-related BMES prevalence showed two peaks, one in adolescence (11-20 years) and one at an older age (51-70 years). BMES predominantly affected the weight-bearing joints, namely, the ankle/foot (55.1%), knee (22.4%) and proximal femur (16.3%). Thyroid disorders and secondary hyperparathyroidism were highly prevalent (21.5 and 21.4%, respectively). On average, the cohort had elevated deoxypyridinoline levels and low 25-OH-D3 levels (19.0 ± 7.5 µg/l in patients without vitamin D supplementation). Osteopenia and osteoporosis were diagnosed in 47.4 and 17.5% of patients, respectively. CONCLUSIONS: BMES is associated with high bone turnover. Patients who are diagnosed with BMES should be screened carefully for bone metabolism disorders and their potential risk factors.

Evaluation of energy metabolism and calcium homeostasis in cells affected by Shwachman-Diamond syndrome.

Isomorphic mutation of the SBDS gene causes Shwachman-Diamond syndrome (SDS). SDS is a rare genetic bone marrow failure and cancer predisposition syndrome. SDS cells have ribosome biogenesis and their protein synthesis altered, which are two high-energy consuming cellular processes. The reported changes in reactive oxygen species production, endoplasmic reticulum stress response and reduced mitochondrial functionality suggest an energy production defect in SDS cells. In our work, we have demonstrated that SDS cells display a Complex IV activity impairment, which causes an oxidative phosphorylation metabolism defect, with a consequent decrease in ATP production. These data were confirmed by an increased glycolytic rate, which compensated for the energetic stress. Moreover, the signalling pathways involved in glycolysis activation also appeared more activated; i.e. we reported AMP-activated protein kinase hyper-phosphorylation. Notably, we also observed an increase in a mammalian target of rapamycin phosphorylation and high intracellular calcium concentration levels ([Ca(2+)]i), which probably represent new biochemical equilibrium modulation in SDS cells. Finally, the SDS cell response to leucine (Leu) was investigated, suggesting its possible use as a therapeutic adjuvant to be tested in clinical trials.

Treatment of Shwachman syndrome by Japanese herbal medicine (Juzen-taiho-to): stimulatory effects of its fatty acids on hemopoiesis in patients.

Juzen-taiho-to (a Japanese herbal medicine) has been traditionally administered to patients with anemia, neutropenia, or wasting syndrome. We previously attempted to isolate and purify the hemopoiesis-stimulatory components in Juzen-taiho-to extracts using an in vitro hemopoietic stem cell (HSC) assay method in which mouse HSCs can proliferate on a stromal cell line (MS-5). We have found that fatty acids (particularly oleic acid and linolenic acid) actively promote the proliferation of HSCs, and that the effect is mediated by stromal cells, rather than by any direct action on the HSCs. In the present study, we show, using human normal bone marrow cells (BMCs) and umbilical cord blood cells, that similar stimulatory effects are due to the presence of oleic acid and linolenic acid, which stimulate the proliferation of HSCs in stroma-based culture systems. Furthermore, a marked stimulatory effect was noted on BMCs from patients with Shwachman syndrome, which shows pancreatic and bone marrow dysfunctions. We also show the data on hemopoietic recovery after the administration of Juzen-taiho-to to a patient with Shwachman syndrome. These findings suggest that decreased fatty acid levels in the blood, caused by exocrine pancreatic insufficiency, induce bone marrow dysfunction in Shwachman syndrome.

A phase I clinical study of the antipurine antifolate lometrexol (DDATHF) given with oral folic acid.

Lometrexol is an antifolate which inhibits glycinamide ribonucleotide formyltransferase (GARFT), an enzyme essential for de novo purine synthesis. Extensive experimental and limited clinical data have shown that lometrexol has activity against tumours which are refractory to other drugs, notably methotrexate. However, the initial clinical development of lometrexol was curtailed because of severe and cumulative antiproliferative toxicities. Preclinical murine studies demonstrated that the toxicity of lometrexol can be prevented by low dose folic acid administration, i.e. for 7 days prior to and 7 days following a single bolus dose. This observation prompted a Phase I clinical study of lometrexol given with folic acid supplementation which has confirmed that the toxicity of lometrexol can be markedly reduced by folic acid supplementation. Thrombocytopenia and mucositis were the major toxicities. There was no clear relationship between clinical toxicity and the extent of plasma folate elevation. Associated studies demonstrated that lometrexol plasma pharmacokinetics were not altered by folic acid administration indicating that supplementation is unlikely to reduce toxicity by enhancing lometrexol plasma clearance. The work described in this report has identified for the first time a clinically acceptable schedule for the administration of a GARFT inhibitor. This information will facilitate the future evaluation of this class of compounds in cancer therapy.