Recent advances in Pharmacology and Toxicology of Phytopharmaceuticals

 

Dr. Shoaib Ahmad

University School of Pharmaceutical Sciences, Rayat-Bahra University, Mohali 140104 India

 

ABSTRACT:

Plants and plant products are directly associated with the existence of human race on earth. Plants are used in several systems of medicine in almost all countries of the world. Many of the medicinal plants have been explored and their contents have been extracted, isolated and identified using a combination of chromatographic and spectral methods. Some of the medicinal plants yield important chemical compounds with a good degree of biological activities. Such plants and chemical compounds find usage in medicine, agriculture, veterinary science, dental practice etc. The exact mechanism of action of most of phytopharmaceuticals is yet to be completely identified. Many people have reported adverse events with the usage of phytopharmaceuticals and their bioactive molecules. Phytopharmaceuticals also have a potential to cause interactions with food and drugs. In very few cases, phytopharmaceuticals  may cause toxicity issues. It has been seen many a times, physicians are not aware of the phytopharmaceuticals available for management of certain diseases and disorders. It is expected more sophisticated omic technologies will be employed to sort out the issues concerning safety and efficacy of phytopharmaceuticals in therapeutic arena. It is prime time to present an overview of the issues related to the pharmacology and toxicology of phytopharmaceuticals.

 

 

 

 

INTRODUCTION:

Phytopharmaceuticals form the basis of phototherapy as well as many of the complimentary and alternative systems of medicine used in Asia, Africa, Europe, America and to some extent in Australia. Human civilizations in the different parts of the world have benefited from the use of medicinal plants as well as the phytopharmaceuticals. The advancements in the techniques of chromatography and spectroscopy have assisted the identification, quantification and isolation of bioactive molecules from phytopharmaceuticals.

 

Quinine, silymarin, rutin, reserpine, vincristine, vinblastine, curcumin, yohimbine, atropine, caffeine, theophylline etc. are some of the well known bioactive molecules found in the medicinal plants, their parts, extracts and tissue cultures. There has always been concern for the safety and efficacy of phyto pharmaceuticals. The scientific community was also apprehensive of the adverse effects, drug interactions and toxicity of phytopharmaceuticals.

 

Establishing the exact mechanism of action of phyto pharmaceuticals and their bioactive molecules is an uphill task. It forms the central basis of usage of phyto pharmaceuticals. and bioactives in the clinical conditions.

 

Phytopharmaceuticals are now becoming a craze amongst the educated classes in developing as well as developed countries¹.

 

Pharmacology: 

Plant extracts and phytopharmaceuticals may affect hepatocytes and nerve cells². Arnica montana flower heads produce anti-inflammatory phytopharmaceuticals³. Brazilian phytopharmaceuticals have been subjected to evaluation against hospital bacteria. 'Astmoflora' and 'Kokolos' were found to be active against Staphylococcus aureus, Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus⁴. Alkaloidal phyto pharmaceuticals have scope for neurodegenerative diseases⁵.

 

Therapeutics:

Clinical development of phytopharmaceuticals has been reported⁶. Phytopharmaceuticals oo-course are useful for general practitioners of medicine⁷. Phytopharmaceuticals -phytotherapy have appeared in literature^8-9. Awareness of phytopharmaceuticals among Mexican primary care physicians has also been reviewed¹⁰. Secondary care hospital physicians in Mexico have low level of awareness of phytopharmaceuticals¹¹. Two phyto pharmaceuticals; namely 'bilicura' and 'spasmobilicura'; have been used in treating GIT and hepatobiliary disorders¹².

 

Plant-based antioxidant systems have been reported to affect HIV progression [HIV progression]¹³. Gingko biloba extract is amongst the phytopharmaceuticals used for treating dementia¹⁴. Salicylate-based phyto pharmaceuticals may have a role in neurological and neuropsychatric disorders¹⁵.

 

Drug Interactions:

Phytopharmaceuticals can cause drug interactions¹⁶.

 

Adverse effects:              

Possible risks of phytopharmaceuticals have been reported¹⁷. Four  phytopharmaceutics namely; Carnivora, Pascotox forte-Injectopas, Esberitox N, Iascador M are known to produce fever, rigor, nausea after parenteral administration¹⁸. Adverse events in case of phytopharmaceuticals can be predicted by in vivo gene expression¹⁹. Phenotyping studies can be used to evaluate the effects of phytopharmaceuticals²⁰.

 

Toxicity:

The use of phytopharmaceuticals in agriculture was doubted to cause chronic toxicity²¹. Reports indicated that the fruits were intoxicated due to residual phytopharmaceuticals²². Pyrrolizidine alkaloids may contaminate phytopharmaceuticals²³.

 

 

CONCLUSION:

There is an emergent need to evaluate the safety, efficacy and toxicity of phytopharmaceuticals. The extensive scientific studies are required to establish the validity of phytopharmaceuticals and increase their acceptance into clinical medicine.

 

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23.     Nowak M, Wittke C, Lederer I, et al. Interspecific transfer of pyrrolizidine alkaloids: An unconsidered source of contaminations of phytopharmaceuticals and plant derived commodities. Food Chem 2016; 213:163-8.

 

 

 

 

 

Received on 15.07.2017                Accepted on 21.09.2017               

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