Preparation and characterization of gelatinized granular starches from aqueous ethanol treatments.

In order to modify the properties of native starch granules, the formation of gelatinized granular forms (GGS) from normal, waxy, and high amylose maize, as well as potato and tapioca starches was investigated by treating granules with aqueous ethanol at varying starch:water:ethanol ratios and then heating in a rotary evaporator to remove ethanol. The modified starches were characterized using bright field, polarized and electron microscopy. Short/long range molecular order and enthalpic transitions on heating were also studied using infrared spectroscopy, X-ray diffractometry and differential scanning calorimetry respectively. A diffuse birefringence pattern without Maltese cross was observed for most GGS samples. Treatment with aqueous ethanol resulted in starch-specific changes in the surface of granules, most noticeably swelling and disintegration in waxy maize, surface wrinkling in normal maize and tapioca, swelling and opening-up in potato starches, and swelling and bursting in high amylose maize. The ratio of ethanol to water at which original granular order was disrupted also varied with starch type. GGS had less short range molecular order than native granules as inferred by comparing 1047/1022 wave number ratio from infrared spectroscopy. Similarly, A- and B-type diffraction reflections were either reduced or completely lost with evolution of V-type patterns in GGS.

Neem (Azadirachta indica) leaf preparation prevents leukocyte apoptosis mediated by cisplatin plus 5-fluorouracil treatment in Swiss mice.

BACKGROUND: Neem (Azadirachta indica) is widely regarded as a wonder tree because of its diverse medicinal applications. We investigated the ability of neem leaf preparation (NLP) to protect against apoptosis of circulating blood cells induced by cisplatin and 5-fluorouracil (cis + 5-FU) in carcinoma-bearing mice. METHODS: Apoptosis was studied by annexin V-propidium iodide method. Total white blood cell count was performed using 3% glacial acetic acid on hemocytometer. Cytotoxicity was determined by LDH release assay and T/NK cell status was determined by flow cytometry. RESULTS: In comparison to untreated control, during cis + 5-FU therapy, significant down-regulation of leukocyte apoptosis was noted in mice pretreated with NLP or granulocyte colony stimulating factor (GCSF) during cis + 5-FU therapy. This enhanced cytotoxicity may be associated with NLP-induced increase of the cytotoxic T and NK cell pool. CONCLUSIONS: Efficacy of NLP is comparable to GCSF in its ability to protect against leukocyte apoptosis induced by cis + 5-FU. NLP would be a better choice of treatment because GCSF is tumor promoting, angiogenic and expensive.

Neem leaf preparation induces apoptosis of tumor cells by releasing cytotoxic cytokines from human peripheral blood mononuclear cells.

A neem leaf preparation (NLP) was investigated for its role in the induction of tumor cell apoptosis to elucidate the mechanism of NLP mediated immunoprophylaxis in tumor growth restriction. As NLP did not induce direct apoptosis of human tumor cell lines KB, MCF7 and K562, it was used instead to stimulate human peripheral blood mononuclear cells (PBMC) for 72 h. The PBMC derived culture supernatant (NLP-CS) was observed to induce the restriction of tumor cell proliferation as well as apoptosis. An enzyme linked immunosorbant assay revealed the presence of cytotoxic cytokines, IFN-gamma and TNF-alpha, in the NLP-CS. The inhibition of secretion of IFN-gamma and TNF-alpha in NLP-CS caused a significant decrease in tumor cell apoptosis. Furthermore, stimulation of these tumor cells with NLP-CS resulted in upregulation of the caspase 3 and downregulation of the Bcl 2 and cyclin D1. These observations suggested that NLP could induce tumor cellular apoptosis by releasing cytotoxic cytokines from human PBMC.

Neem (Azadirachta indica) leaf preparation induces prophylactic growth inhibition of murine Ehrlich carcinoma in Swiss and C57BL/6 mice by activation of NK cells and NK-T cells.

We have reported earlier that pretreatment of mice with neem leaf preparation (NLP) causes prophylactic growth inhibition of murine Ehrlich's carcinoma (EC) and B16 melanoma. Using adoptive cell transfer technology, here we have established that NLP-mediated activation of immune cells may be involved in tumor growth restriction. Mononuclear cells from blood and spleen of NLP-activated Swiss and C57BL/6 mice causes enhanced cytotoxicity to murine EC cells in vitro. Fractionation of spleen cells exhibited greater percentage of tumor cell lysis in macrophage and B-cell-depleted NK and T-cell-rich fractions. Flow cytometric analysis revealed in both blood and spleen, NK cells (DX5+ or NK1.1+) and NK-T cells (CD3+/DX5+ or CD3+/NK1.1+) were increased in number in Swiss, C57BL/6 and athymic nude mice after pretreatment with NLP. NLP-stimulated spleen cells showed greater secretion of TNFalpha and IFNgamma. Thus, NLP-activated NK and NK-T cells in mice may regulate tumor cell cytotoxicity by enhancing the secretion of different cytotoxic cytokines.

Pretreatment with neem (Azadirachta indica) leaf preparation in Swiss mice diminishes leukopenia and enhances the antitumor activity of cyclophosphamide.

Cancer chemotherapy is associated with several life threatening complications, including bone marrow suppression and leucopenia. To overcome this problem, colony stimulating factor (CSF), granulocyte colony stimulating factor (GCSF) and granulocyte macrophage colony stimulating factor (GMCSF), can be used, however, these therapeutics are expensive and have several disadvantages, including tumor growth promoting activities. This study attempted to use an immunostimulatory neem (Azadirachta indica) leaf preparation (NLP) to prevent the cyclophosphamide (CYP) induced reduction in the WBC count. Pretreatment of mice with NLP reduced the extent of leucopenia and neutropenia in normal and tumor bearing CYP treated mice. NLP pretreatment enhanced in vitro tumor cell cytotoxicity by peripheral blood mononuclear cells (PBMC) from CYP treated mice in either normal or tumor bearing conditions. Similarly, NLP pretreatment of mice enhanced the CYP mediated in vivo tumor growth inhibition and survivability of the host. Based on these observations, it is concluded that NLP would be an effective tool to reduce CYP-induced hematological complications.

Prophylactic dose of neem (Azadirachta indica) leaf preparation restricting murine tumor growth is nontoxic, hematostimulatory and immunostimulatory.

Significant restriction of growth of Ehrlich's carcinoma was observed following prophylactic treatment on Swiss albino mice with neem leaf preparation (NLP-1 unit) once weekly for four weeks. Toxic effects of this particular dose (1 unit), along with 0.5 unit and 2 units of NLP doses, were evaluated on different murine physiological systems. One hundred percent of mice could tolerate 4 injections of 0.5 and 1 unit NLP doses. Body weight, different organ-body weight ratios and physical behavior of treated mice remained completely unchanged during treatment with different NLP doses. All of these NLP doses were observed to stimulate hematological systems as evidenced by the increase in total count of RBC, WBC and platelets and hemoglobin percentage. As histological changes as well as elevation in serum alkaline phosphatase, SGOT, SGPT were not observed in mice treated with three different doses of NLP, the nonhepatotoxic nature of NLP was proved. The level of serum urea remained unaltered and normal architecture of the cortical and medullary parts of the kidney were also preserved after NLP treatment. Increased antibody production against B16 melanoma antigen was detected in mice immunized with 0.5 unit and 1 unit of NLP. Number of splenic T lymphocytes (CD4+ and CD8+) and NK cells were also observed to be increased in mice injected with 0.5 unit and 1 unit of NLP. However, NLP dose of 2 units could not exhibit such immunostimulatory changes; NLP mediated immunostimulation was correlated well with the growth restriction of murine carcinoma. In other words, tumor growth restriction was observed only when mice were injected with immunostimulatory doses of NLP (0.5 unit and 1 unit).