The Genotoxicity Status of Senna

Abstract

Genotoxicity tests were performed by several laboratories with the drug fructus sennae, senna extract, sennosides, rhein and aloe-emodin. The drug fructus sennae, the sennosides and rhein did not increase mutation frequencies in the following test systems: bacterial systems (Salmonella reverse mutation test and/or Escherichia coli forward mutation test); mammalian cell cultures [hypoxanthine guanine phosphoribosyl transfer-ase (HGPRT) test; mouse lymphoma test; chromosome aberration test with Chinese hamster ovary cells]; bone marrow (micronucleus test; chromosome aberration test); melanoblast cells (mouse spot test) of rodents. With aloe-emodin mutagenic effects were observed only in vitro in the chromosome aberration test with CHO cells and in the Salmonella reverse mutation test (frameshift mutations in strains TA 1537, TA 1538 and TA 98). In the in vitro gene mutation test with V79 cells (HGPRT test) no mutagenic potential of aloe-emodin was observed. In in vivo studies [micronucleus test with bone marrow cells of NMRI mice, chromosome aberration test with bone marrow cells of Wistar rats, mouse spot test (crossing DBA/2J × NMRI) no indication for a mutagenic activity of aloe-emodin was found. The relevance of the absence of a mutagenic potential in in vivo test systems was strengthened by the fact that aloe-emodin could be found in the blood serum after oral administration. Additional information on the interaction of aloe-emodin with DNA was obtained from an ex vivo unscheduled DNA synthesis test performed with hepatocytes of male Wistar rats: aloe-emodin did not induce unscheduled DNA synthesis as expression of DNA damage. The extract of senna induced gene mutations in bacteria (frame shift mutations in TA 1537 and TA 98), but a negative result was obtained in the gene mutation test with V79 cells (HGPRT test). In the chromosome aberration test with CHO cells the senna extract induced structural chromosomal aberrations. The results demonstrate that an extract of senna and aloe-emodin were genotoxic when tested with some in vitro test systems. Under in vivo conditions so far no genotoxic effect was found. The drug fructus sennae, the sennosides and rhein were negative under in vitro as well as under in vivo conditions.

In vitro Evaluation of Genotoxicity of Avocado (Persea americana) Fruit and Leaf Extracts in Human Peripheral Lymphocytes

“…The assay has been previously used to evaluate the genotoxicity of plant extracts [40][41][42]. Since several cytotoxic principles have been isolated from avocado fruit and leaf extracts as has been already discussed, our present study evaluates and compares the potential genotoxicity of the avocado leaf and fruit extracts.…”

A 13-week oral toxicity study of senna in the rat with an 8-week recovery period

“…They show low toxicity in rats and dogs following single or repeated dose administration and gave no evidence of any teratogenic or genotoxic activity (Mengs 1986(Mengs , 1988Heidemann et al 1993), which is also true for the main metabolite rhein (Heidemann et al 1993). However, the toxicity of the entire senna drug is less well documented.…”

“…However, the toxicity of the entire senna drug is less well documented. In recent years, several in vitro experiments have shown mutagenic effects of senna itself and of several anthranoid constituents, particularly aloe-emodin and emodin, which can be isolated from the drug in small trace amounts (Westendorf et al 1990;Heidemann et al 1993). In addition, the synthetic anthranoid laxative danthron has also been demonstrated to induce tumors in rodent long-term studies (Mori et al 1985(Mori et al , 1986.…”

Absence of mutagenic and citotoxic potentiality of senna (Cassia angustifolia Vahl.) evaluated by microbiological tests

“…Chronic use or abuse of this agent can lead to a number of symptoms and signs, such as abdominal pain, nausea and diarrhoea 3,4,5 . Many studies have investigated the mutagenic and carcinogenic effects of senna in bacterial strains, animals and humans 4,5,6 . Ames test detected a weak mutagenic potentiality in Salmonella typhimurium TA102 and a stronger mutagenicity in Salmonella typhimurium TA97 and TA98…”

“…Senna (Cassia angustifolia Vahl) is widely used in clinical practice and as a self-medication for chronic constipation. Chronic use or abuse of this agent can lead to a number of symptoms and signs, such as abdominal pain, nausea and diarrhoea 3,4,5 . Many studies have investigated the mutagenic and carcinogenic effects of senna in bacterial strains, animals and humans 4,5,6 .…”