Antiviral Activity of Jamaican Medicinal Plants and Isolated Bioactive Compounds

Abstract

Plants have had historical significance in medicine since the beginning of civilization. The oldest medical pharmacopeias of the African, Arabian, and Asian countries solely utilize plants and herbs to treat pain, oral diseases, skin diseases, microbial infections, multiple types of cancers, reproductive disorders among a myriad of other ailments. The World Health Organization (WHO) estimates that over 65% of the world population solely utilize botanical preparations as medicine. Due to the abundance of plants, plant-derived medicines are more readily accessible, affordable, convenient, and have safer side-effect profiles than synthetic drugs. Plant-based decoctions have been a significant part of Jamaican traditional folklore medicine. Jamaica is of particular interest because it has approximately 52% of the established medicinal plants that exist on earth. This makes the island particularly welcoming for rigorous scientific research on the medicinal value of plants and the development of phytomedicine thereof. Viral infections caused by the human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2), hepatitis virus B and C, influenza A virus, and the severe acute respiratory syndrome coronavirus 2 (SARS CoV-2) present a significant global burden. This is a review of some important Jamaican medicinal plants, with particular reference to their antiviral activity.

Keywords: antivirals; phytoantiviral; phytomedicine; viral infections.

Figure 1

Some Jamaican plants with major antiviral activity.

Figure 2

Chemical structures of some bioactive molecules found in Tillandsia recurvata L.

Figure 3

Chemical structures of some bioactive molecules found in A. vera.

Figure 4

Chemical structures of some bioactive molecules found in C. sativa L.

Figure 5

Chemical structures of dibenzyl trisulfide (DTS) found in Guinea Hen Weed.

Figure 6

A possible antiviral mechanism of DTS in an infected cell. The mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK ERK1/ERK2 pathway) is a signaling pathway that is responsible for the transduction of protein components (chemical signals, transcription factors), MAP kinase kinase (MAP2K), and a final kinase, MAP kinase (MAPK), leading to the functioning and regulation of multiple cellular processes like cell proliferation, cell growth, and cell survival. A dysregulation of this pathway or any of its components typically has pathological consequences [43,44]. It has been proposed that some pathological conditions are characterized by increased phosphorylation of kinases [45], possibly resulting in over-proliferation of cells. Dibenzyl trisulfide (DTS) is shown to inhibit the MAPK ERK1/ERK2 pathway in cancer- and (possibly) virally infected cells via dephosphorylation of ERK1/2, ultimately resulting in apoptosis of the cell [45]. MAP—mitogen-activated protein; K—kinase; Raf—rapidly accelerated fibrosarcoma; MEK—mitogen-activated protein kinase.

Figure 7

A possible anti-HIV-1 mechanism of DTS in a CD4 cell.

Figure 8

Chemical structures of some bioactive molecules found in Zingiber officinale Roscoe.

Figure 8

Chemical structures of some bioactive molecules found in Zingiber officinale Roscoe.

Figure 9

A possible antiviral mechanism of ginger (Zingiber officinale Roscoe). It is possible that ginger blocks viral attachment and internalization via stimulation of mucosal cells of the respiratory tract to secrete interferon-β (IFN-β) [46].

Figure 10

Chemical structure of curcumin (diferuloylmethane) found in Curcuma Longa L.

Figure 11

A possible anti-HIV-1 mechanism of curcumin by inhibition of HIV-1 integrase. This prevents integration of HIV-1 DNA into host cell DNA and ultimately inhibition of viral replication, assembly, budding and infection of new cells.

Figure 12

Chemical structures of some bioactive molecules found in Moringa oleifera Lam.

Figure 12

Chemical structures of some bioactive molecules found in Moringa oleifera Lam.

Figure 13

Chemical structures of some bioactive molecules found in Lignum Vitae.

Figure 14

The conversion of organosulfur compounds in garlic [64].

Figure 15

Possible anti-influenza mechanisms of garlic. Organosulfur compounds produced by garlic may inhibit various stages of the general virus life cycle including viral attachment, entry and multiplication [65]. Another possible mechanism of action is via inhibition of components of viral signaling pathways [65].

Figure 16

Chemical structures of some bioactive molecules found in garlic.

Figure 16

Chemical structures of some bioactive molecules found in garlic.

Figure 17

Chemical structures of some bioactive molecules found in sorrel.

Figure 17

Chemical structures of some bioactive molecules found in sorrel.

Figure 17

Chemical structures of some bioactive molecules found in sorrel.