An Insight Into the Modulatory Effects and Mechanisms of Action of Phyllanthus Species and Their Bioactive Metabolites on the Immune System.

Ibrahim Jantan,Laiba Arshad,Menaga Ilangkovan,Md Areeful Haque

doi:10.3389/fphar.2019.00878

Abstract

Phyllanthus species (family; Euphorbiaceae) have been intensively studied for their immunomodulating effects due to their wide-ranging uses to treat immune-related diseases in indigenous medicine, which are primarily lack of scientific basis. The focuses of this review are on the significance of Phyllanthus species and their bioactive metabolites particularly corilagin (1), geraniin (2), gallic acid (3), phyllanthin (4), hypophyllanthin (5), ellagic acid (6), phyltetralin (7), niranthin (8), catechin (9), quercetin (10), astragalin (11), and chebulagic acid (12) in the modulation of both innate and adaptive immune systems through various mechanisms and their possible therapeutic benefits for treatment of immune-related diseases. We have compiled all significant findings published in the literature, and the data were analyzed critically to provide perspectives and directions for future research for the plants as a prospective source of novel immunomodulating agents. Various Phyllanthus species particularly Phyllanthus amarus, Phyllanthus emblica, Phyllanthus niruri, and Phyllanthus urinaria have been documented to possess significant immunomodulatory effects. However, the possible challenges encountered by the application of extracts of various Phyllanthus species and their bioactive constituents as immunomodulators need to be addressed. Most reports on the biological and pharmacological studies of the plants were based on crude extracts. The extracts were not chemically characterized, and the contributions of their chemical constituents to the bioactivities were not identified. The underlying mechanisms involved in the immunomodulatory effects of the Phyllanthus species were not indepthly studied due to limitations in terms of design, conduct, and interpretation. Extensive experimental and preclinical studies on the immunomodulating potential of Phyllanthus species should be carried out to provide sufficient data to prove that their traditional uses are inherently effective and safe and will allow clinical trials to be pursued for their further development as therapeutic agents to treat immune-related disorders.

Highlights

The immune system is composed of white blood cells and specialized immune molecules that have developed to bring about resistance to infections
The main focus of this review is on the immunomodulatory effects of several Phyllanthus species, i.e., Phyllanthus amarus, Phyllanthus urinaria, Phyllanthus emblica, Phyllanthus niruri, Phyllanthus acidus, Phyllanthus fraternus, Phyllanthus reticulatus, and Phyllanthus simplex that are extensively used in indigenous medicine for healing immune-related diseases and their reported immunomodulating properties in cell, animal, or human studies
NO is basically released in huge quantity from the amino acid l-arginine by the inducible nitric oxide synthase which is expressed by many immune cells especially macrophages upon exposure to various stimuli including bacterial LPS, cytokine, or viruses (Chakraborty et al, 2012)

Summary

Introduction

The immune system is composed of white blood cells (neutrophils, lymphocytes, macrophages, and monocytes) and specialized immune molecules (cytokines, antibodies, and complement proteins) that have developed to bring about resistance to infections. The main focus of this review is on the immunomodulatory effects of several Phyllanthus species, i.e., Phyllanthus amarus, Phyllanthus urinaria, Phyllanthus emblica, Phyllanthus niruri, Phyllanthus acidus, Phyllanthus fraternus, Phyllanthus reticulatus, and Phyllanthus simplex that are extensively used in indigenous medicine for healing immune-related diseases and their reported immunomodulating properties in cell, animal, or human studies.

Results

Conclusion