Anti-inflammatory activity of flower extract of Calendula officinalis Linn. and its possible mechanism of action.

Calendula officinalis flower extract possessed significant anti-inflammatory activity against carrageenan and dextran-induced acute paw edema. Oral administration of 250 and 500 mg/kg body weight Calendula extract produced significant inhibition (50.6 and 65.9% respectively) in paw edema of animals induced by carrageenan and 41.9 and 42.4% respectively with inflammation produced by dextran. In chronic anti-inflammatory model using formalin, administration of 250 and 500 mg/kg body weight Calendula extract produced an inhibition of 32.9 and 62.3% respectively compared to controls. TNF-alpha production by macrophage culture treated with lipopolysaccharide (LPS) was found to be significantly inhibited by Calendula extract. Moreover, increased levels of proinflammatory cytokines IL- 1beta, IL-6, TNF-alpha and IFN-gamma and acute phase protein, C- reactive protein (CRP) in mice produced by LPS injection were inhibited significantly by the extract. LPS induced cyclooxygenase-2 (Cox-2) levels in mice spleen were also found to be inhibited by extract treatment. The results showed that potent anti-inflammatory response of C. officinalis extract may be mediated by the inhibition of proinflammatory cytokines and Cox-2 and subsequent prostaglandin synthesis.

Immunostimulatory action of AC II--an ayurvedic formulation useful in HIV.

Immunostimulatory activity of AC II, a registered ayurvedic preparation prepared at Amala Ayurvedic Research Centre for treating HIV and AIDS is reported. AC II administration could significantly enhance the mitogen-induced proliferation of lymphocytes of spleen cells. It was also found to increase cell-mediated immune responses in normal and tumor-bearing control animals. Oral administration of AC II significantly enhanced Natural Killer cell activity in normal and tumor-bearing animals on the 7th day, which was observed earlier than the tumor-bearing control animals and normal animals. Antibody dependent cellular cytotoxicity (ADCC) was also increased in AC II treated normal and tumor-bearing animals. An early enhancement of antibody-dependent complement-mediated cytotoxicity was also observed by the administration of AC II in normal as well as tumor-bearing animals. Treatment with AC II elevated the levels of IL-2, TNF-alpha and IFN-gamma in normal mice. Administration of AC II was also found to increase the cytotoxic T lymphocyte production in EL4 treated mice. These studies support the use of this immune stimulatory preparation in HIV patients.

Effect of homeopathic medicines on transplanted tumors in mice.

Ultra low doses used in homeopathic medicines are reported to have healing potential for various diseases but their action remains controversial. In this study we have investigated the antitumour and antimetastatic activity of selected homeopathic medicines against transplanted tumours in mice. It was found that Ruta graveolens 200c and Hydrastis canadensis 200c significantly increased the lifespan of Ehrlich Ascites Carcinoma and Dalton's Lymphoma Ascites induced tumour-bearing animals by 49.7%, and 69.4% respectively. Moreover there was 95.6% and 95.8% reduction of solid tumour volume in Ruta 200c and Hydrastis 200c treated animals on the 31st day after tumour inoculation. Hydrastis 1M given orally significantly inhibited the growth of developed solid tumours produced by DLA cells and increased the lifespan of tumour bearing animals. Some 9 out of 15 animals with developed tumors were completely tumour free after treatment with Hydrastis 1M. Significant anti-metastatic activity was also found in B16F-10 melanoma-bearing animals treated with Thuja1M, Hydrastis 1M and Lycopodium1M. This was evident from the inhibition of lung tumour nodule formation, morphological and histopathological analysis of lung and decreased levels of gamma-GT in serum, a cellular marker of proliferation. These findings support that homeopathic preparations of Ruta and Hydrastis have significant antitumour activity. The mechanism of action of these medicines is not known at present.

Immunomodulatory and antitumor activity of Biophytum sensitivum extract.

An alcoholic extract of Biophytum sensitivum was studied for its immunomodulatory and antitumor activity. The extract was 100% toxic at a concentration of 0.5 mg/ml to Dalton's lymphoma ascites (DLA) and Ehrlich ascites carcinoma (EAC) cells. B. sensitivum extract was also found to be cytotoxic towards L929 cells in culture at a concentration of 0.1 mg/ml. Administration of B. sensitivum extract (500 microg/dose/animal) could inhibit the solid tumor development in mice induced with DLA cells and increase the lifespan of mice bearing Ehrlich ascites carcinoma tumors by 93.3%. B. sensitivum treatment significantly (p<0.001) reduced the tumor cell glutathione (GSH) levels as well as serum gamma glutamyl transpeptidase (GGT) and nitric oxide (NO) levels in ascites tumor bearing animals. The total WBC count was also increased to 14,087 cells/mm(3) on the 12th day in BALB/c mice. The number of plaque forming cells also enhanced significantly (p<0.001), and bone marrow cellularity and beta-esterase positive cells were also increased by the administration of B. sensitivum extract.

Inhibition of chemically induced carcinogenesis by drugs used in homeopathic medicine.

Homeopathy is considered as one modality for cancer therapy. However, there are only very few clinical reports on the activity of the drugs, as well as in experimental animals. Presently we have evaluated the inhibitory effects of potentized homeopathic preparations against N'-nitrosodiethylamine (NDEA) induced hepatocellular carcinoma in rats as well as 3-methylcholanthrene-induced sarcomas in mice. We have used Ruta, Hydrastis, Lycopodium and Thuja, which are commonly employed in homeopathy for treating cancer. Administration of NDEA in rats resulted in tumor induction in the liver and elevated marker enzymes such as gamma-glutamyl transpeptidase, glutamate pyruvate transaminase, glutamate oxaloacetate transaminase and alkaline phosphatase in the serum and in liver. Concomitant administration of homeopathic drugs retarded the tumor growth and significantly reduced the elevated marker enzymes level as revealed by morphological, biochemical and histopathological evaluation. Out of the four drugs studied, Ruta 200c showed maximum inhibition of liver tumor development. Ruta 200c and phosphorus 1M were found to reduce the incidence of 3-methylcholanthrene-induced sarcomas and also increase the life span of mice harboring the tumours. These studies demonstrate that homeopathic drugs, at ultra low doses, may be able to decrease tumor induction by carcinogen administration. At present we do not know the mechanisms of action of these drugs useful against carcinogenesis.

Effect of AC II, a herbal formulation on radiation-induced immunosuppression in mice.

A single dose of 6 Gy irradiation significantly reduced the total WBC count while in herbal formulation (AC II) treated groups it was found to be significantly increased. Similarly bone marrow cellularity and alpha-esterase positive cells, which were lowered by radiation, were partly restored in AC II treated groups. The data indicate that AC II can overcome the immunosuppression produced by irradiation.

Anti-tumour activity of Ruta graveolens extract.

An extract of Ruta graveolens was found to be cytotoxic to Dalton's lymphoma ascites (DLA), Ehrlich ascites carcinoma (EAC) and L929 cells in culture (IC100=16 mg/ml) and also to increase the lifespan of tumour bearing animals. The extract further decreased solid tumours developing from DLA and EAC cells when given simultaneously with elongation of the lifespan of tumour-bearing animals. A homeopathic preparation of Ruta graveolens (200 c) was equally effective. Neither was effective for reducing already developed tumours. The Ruta graveolens extract was found to scavenge hydroxyl radicals and inhibit lipid peroxidation at low concentrations. However, at higher concentrations the extract acted as a prooxidant as inhibition of lipid peroxidation and scavenging of hydroxyl radical was minimal. These data indicates that the prooxidant activity of Ruta graveolens may be responsible for the cytocidal action of the extract and its ability to produce tumour reduction.

Immunopotentiating activity of abrin, a lectin from Abrus precatorius Linn.

A non-toxic dose of abrin, (1.25 microg/kg body wt) consecutively for five days in normal mice stimulated specific humoral responses. A noticeable increase was observed in total leucocyte count, lymphocytosis, weights of spleen and thymus, circulating antibody titre, antibody forming cells, bone marrow cellularity and alpha-esterase positive bone marrow cells. The results suggest that abrin can potentiate the humoral immune response of the host.

Antitumour effect of abrin on transplanted tumours in mice.

Abrin, a galactose specific lectin was purified using sepharose 4B affinity column from seeds of Abrus precatorius. It exhibited antitumour activity in mice when used at a sublethal dose of 7.5 micrograms/kg every alternate day for 10 days. Both intralesional and intraperiloneal (i.p.) administration of abrin was effective in reducing solid tumour mass development induced by Dalton's Lymphoma Ascites (DLA) and Ehrlich's Ascites Carcinoma (EAC) cells. DLA cell line was more sensitive to abrin than EAC. Abrin when injected i.p. increased the life span of ascites tumour bearing mice. Abrin when used simultaneously with tumour cells brought about maximum antitumour effect. On developed tumour masses, abrin administration brought about significant reduction in tumour volume, especially in DLA induced tumours. Prophylactic administration of abrin was found ineffective.