Screening of antileishmanial activity from marine sponge extracts collected off the Tunisian coast

Phytochemical study of Seriphidium khorassanicum (syn. Artemisia khorassanica) aerial parts: sesquiterpene lactones with anti-protozoal activity

Two new eudesmane-type sesquiterpene lactones, 1β,3α,8α-trihydroxy-11β,13-dihydroeudesma-4(15)-en-12,6α-olide (1) and 1β,4α,8α-trihydroxy-11β,13-dihydroeudesma-12,6α-olide (2), and an unprecedented elemane-type sesquiterpene lactone, 1β,2β,8α-trihydroxy-11β,13-dihydroelema-12,6α-olide (3) along with a known eudesmanolide artapshin (4) were isolated from Seriphidium khorassanicum. Structures were elucidated by NMR, HR-ESI-MS, and ECD spectral data analysis. The anti-protozoal activity was evaluated against Leishmania major promastigotes and amastigote-infected macrophages. They showed dose- and time-dependent activity against L. major amastigotes with IC50 values in the range of 4.9 to 25.3 μM being favourably far below their toxicity against normal murine macrophages with CC50 values ranging from 432.5 to 620.7 μM after 48 h of treatment. Compound 3 exhibited the strongest activity and the highest selectivity index (SI) with IC50 of 4.9 ± 0.6 μM and SI of 88.2 comparable with the standard drug, meglumine antimoniate (Glucantime), with IC50 and SI values of 15.5 ± 2.1 μM and 40.0, respectively.

Promising antiparasitic agents from marine sponges

Parasitic diseases especially those prevail in tropical and subtropical regions severely threaten the lives of people due to available drugs found to be ineffective as several resistant strains have been emerged. Due to the complexity of the marine environment, researchers considered it as a new field to search for compounds with therapeutic efficacy, marine sponges represents the milestone in the discovery of unique compounds of potent activities against parasitic infections. In the present article, literatures published from 2010 until March 2021 were screened to review antiparasitic potency of bioactive compounds extracted from marine sponges. 45 different genera of sponges have been studied for their antiparasitic activities. The antiparasitic activity of the crude extract or the compounds that have been isolated from marine sponges were assayed in vitro against Plasmodium falciparum, P. berghei, Trypanosoma brucei rhodesiense, T. b. brucei, T. cruzi, Leishmania donovani, L. tropica, L. infantum, L. amazonesis, L. major, L. panamesis, Haemonchus contortus and Schistosoma mansoni. The majority of antiparastic compounds extracted from marine sponges were related to alkaloids and peroxides represent the second important group of antiparasitic compounds extracted from sponges followed by terpenoids. Some substances have been extracted and used as antiparasitic agents to a lesser extent like steroids, amino acids, lipids, polysaccharides and isonitriles. The activities of these isolated compounds against parasites were screened using in vitro techniques. Compounds' potent activity in screened papers was classified in three categories according to IC₅₀: low active or inactive, moderately active and good potent active.

An Update on Natural Antileishmanial Treatment Options from Plants, Fungi and Algae

Efficient drugs for the treatment of leishmaniasis, which is classified as a neglected tropical disease, are sought for. This review covers potential drug candidates from natural plant, fungus and algae sources, which were described over the last six years. The identification of these natural antileishmanials often based on the knowledge of traditional medicines. Crucial insights into the activities of these natural remedies against Leishmania parasites and against infections caused by these parasites in laboratory animals or patients are provided and compared with selected former active examples published more than six years ago. In addition, immuno-modulatory natural antileishmanials and recent developments on combination therapies including natural products and approved antileishmanials are discussed. The described natural products revealed promising data warranting further efforts on the discovery and development of new antileishmanials based on patterns from nature.

Exploring Antimicrobials from the Flora and Fauna of Marine: Opportunities and Limitations

About 95% of earth living space lies deep below the ocean's surface and it harbors extraordinary diversity of marine organisms. Marine biodiversity is an exceptional reservoir of natural products, bioactive compounds, nutraceuticals and other potential compounds of commercial value. Timeline for the development of the drug from a plant, synthetic and other alternative sources is too lengthy. Exploration of the marine environment for potential bioactive compounds has gained focus and huge opportunity lies ahead for the exploration of such vast resources in the ocean. Further, the evolution of superbugs with increasing resistance to the currently available drugs is alarming and it needs coordinated efforts to resolve them. World Health Organization recommends the need and necessity to develop effective bioactive compounds to combat problems associated with antimicrobial resistance. Based on these factors, it is imperative to shift the focus towards the marine environment for potential bioactive compounds that could be utilized to tackle antimicrobial resistance. Current research trends also indicate the huge strides in research involving marine environment for drug discovery. The objective of this review article is to provide an overview of marine resources, recently reported research from marine resources, challenges, future research prospects in the marine environment.

Report of in vitro antileishmanial properties of Iberian macroalgae

Here is reported the anti Leishmania infantum activity of 48 hexane, CH2Cl2 and MeOH extracts from 16 macroalgae collected on the Iberian Coast. Seven hexane and CH2Cl2 Cystoseira baccata, Cystoseira barbata, Cystoseira tamariscifolia, Cystoseira usneoides, Dictyota spiralis and Plocamium cartilagineum extracts were active towards promastigotes (IC50 29.8-101.8 μg/mL) inducing strong morphological alterations in the parasites. Hexane extracts of C. baccata and C. barbata were also active against intracellular amastigotes (IC50 5.1 and 6.8 μg/mL, respectively). Fatty acids, triacylglycerols, carotenoids, steroids and meroterpenoids were detected by nuclear magnetic resonance (NMR), and gas chromatography in the Cystoseira extracts. These results suggest that Cystoseira macroalgae contain compounds with antileishmanial activity, which could be explored as scaffolds to the development of novel sources of antiparasitic derivatives.

Marine natural products for multi-targeted cancer treatment: A future insight

Cancer is world's second largest alarming disease, which involves abnormal cell growth and have potential to spread to other parts of the body. Most of the available anticancer drugs are designed to act on specific targets by altering the activity of involved transporters and genes. As cancer cells exhibit complex cellular machinery, the regeneration of cancer tissues and chemo resistance towards the therapy has been the main obstacle in cancer treatment. This fact encourages the researchers to explore the multitargeted use of existing medicines to overcome the shortcomings of chemotherapy for alternative and safer treatment strategies. Recent developments in genomics-proteomics and an understanding of the molecular pharmacology of cancer have also challenged researchers to come up with target-based drugs. The literature supports the evidence of natural compounds exhibiting antioxidant, antimitotic, anti-inflammatory, antibiotic as well as anticancer activity. In this review, we have selected marine sponges as a prolific source of bioactive compounds which can be explored for their possible use in cancer and have tried to link their role in cancer pathway. To prove this, we revisited the literature for the selection of cancer genes for the multitargeted use of existing drugs and natural products. We used Cytoscape network analysis and Search tool for retrieval of interacting genes/ proteins (STRING) to study the possible interactions to show the links between the antioxidants, antibiotics, anti-inflammatory and antimitotic agents and their targets for their possible use in cancer. We included total 78 pathways, their genes and natural compounds from the above four pharmacological classes used in cancer treatment for multitargeted approach. Based on the Cytoscape network analysis results, we shortlist 22 genes based on their average shortest path length connecting one node to all other nodes in a network. These selected genes are CDKN2A, FH, VHL, STK11, SUFU, RB1, MEN1, HRPT2, EXT1, 2, CDK4, p14, p16, TSC1, 2, AXIN2, SDBH C, D, NF1, 2, BHD, PTCH, GPC3, CYLD and WT1. The selected genes were analysed using STRING for their protein-protein interactions. Based on the above findings, we propose the selected genes to be considered as major targets and are suggested to be studied for discovering marine natural products as drug lead in cancer treatment.

Medicinal plants with promising antileishmanial activity in Iran: a systematic review and meta-analysis

BACKGROUND

Leishmaniasis is a major public health problem worldwide. The aim of the present study was to investigate medicinal plants with anti-Leishmania activity which used in Iran.

METHODS

Data were systematically gathered from five English databases including Ebsco, Science Direct, PubMed, Google Scholar and Scopus, four Persian databases including Magiran, Iran doc, Iran medex and the Scientific Information Database (SID) from 1999 to April 2015. Information obtained included plant family, extraction method, concentrations of extracts, animal models and parasite strains.

RESULTS

A total of 68 articles including 188 experiments (140 in vitro and 48 in vivo) between 1999 and 2015, met our eligibility criteria. Thoroughly, 98 types of plants were examined against three genera of Leishmania spp. For the heterogeneity study conducted, it was showed that there was a great deal of variation among studies. Based on random effect, meta-analysis pooled mean of IC50 was obtained 456.64 (95% CI: 396.15, 517.12).

CONCLUSION

The most Iranian plants used as anti-leishmanial activity were Artemisia species, Allium sativum, Achilleamille folium, Peganum harmala and Thymus vulgaris. The present systematic and meta-analysis review provide valuable information about natural products with anti-Leishmania activity, which would be examined in the future experimental and clinical trials and herbal combination therapy.

Exploring the ocean for new drug developments: Marine pharmacology

Disease ailments are changing the patterns, and the new diseases are emerging due to changing environments. The enormous growth of world population has overburdened the existing resources for the drugs. And hence, the drug manufacturers are always on the lookout for new resources to develop effective and safe drugs for the increasing demands of the world population. Seventy-five percentage of earth's surface is covered by water but research into the pharmacology of marine organisms is limited, and most of it still remains unexplored. Marine environment represents countless and diverse resource for new drugs to combat major diseases such as cancer or malaria. It also offers an ecological resource comprising a variety of aquatic plants and animals. These aquatic organisms are screened for antibacterial, immunomodulator, anti-fungal, anti-inflammatory, anticancer, antimicrobial, neuroprotective, analgesic, and antimalarial properties. They are used for new drug developments extensively across the world. Marine pharmacology offers the scope for research on these drugs of marine origin. Few institutes in India offer such opportunities which can help us in the quest for new drugs. This is an extensive review of the drugs developed and the potential new drug candidates from marine origin along with the opportunities for research on marine derived products. It also gives the information about the institutes in India which offer marine pharmacology related courses.

Marine pharmacology in 2009-2011: marine compounds with antibacterial, antidiabetic, antifungal, anti-inflammatory, antiprotozoal, antituberculosis, and antiviral activities; affecting the immune and nervous systems, and other miscellaneous mechanisms of action

The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.