A Review of the Pharmacological Activities and Safety of Heliotropium indicum

Heliotropium indicum L. is distributed over Africa, Asia, Europe and North America. Its use in folkloric medicine covers treatment for asthma, rheumatism, skin disorders, snakebites, and inflammation. However, there are misgivings about its safety due to reports of adverse events and the presence of toxic alkaloids. This study thus summarizes the various pharmacological activities and safety studies on H. indicum through a scoping review. Sixty-eight (68) publications were retrieved from SCOPUS, CINAHL Complete, PubMed, and Cochrane Library, of which 19 articles were analyzed. The major pharmacological activities investigated in these articles included the anti-allergic, anti-glaucoma, wound healing, histo-gastro-protective, antitumor, antimitotic, neuroprotective, anti-proliferative, anti-nociceptive, anti-ulcer, cytotoxic, anti-inflammatory, antioxidant, anti-dyslipidemia, anti-cataractogenic and cytostatic activities. Two studies on the safety of H. indicum were performed in horse and mouse models, and two other studies on the plant pyrrolizidine alkaloid indicine N-oxide, in human and cell lines. Recorded adverse effects were bile pigment accumulation in the spleen, and brain abnormalities in the cerebral cortex in animal model. Indicine N-oxide, a highly toxic substance, caused dose-dependent mortality in Swiss mice, at a lethal dose of 9.78 grams per kilogram of body weight, with adverse effects seen on the liver and kidneys. Also, inflammatory alterations were observed in the testicles. Pharmacological studies on H. indicum revealed noteworthy potential as a rich source of bioactive substances. The reported side effects highlight the need for a cautious approach to its use and to prioritize safety assessments. Major Findings: Heliotropium indicum has been investigated for a wide range of pharmacological activities; however, there have also been a reports of possible injuries to the spleen and brain in animals.