Oceans as a Source of Immunotherapy

Immunomodulatory Compounds from the Sea: From the Origins to a Modern Marine Pharmacopoeia

From sea shores to the abysses of the deep ocean, marine ecosystems have provided humanity with valuable medicinal resources. The use of marine organisms is discussed in ancient pharmacopoeias of different times and geographic regions and is still deeply rooted in traditional medicine. Thanks to present-day, large-scale bioprospecting and rigorous screening for bioactive metabolites, the ocean is coming back as an untapped resource of natural compounds with therapeutic potential. This renewed interest in marine drugs is propelled by a burgeoning research field investigating the molecular mechanisms by which newly identified compounds intervene in the pathophysiology of human diseases. Of great clinical relevance are molecules endowed with anti-inflammatory and immunomodulatory properties with emerging applications in the management of chronic inflammatory disorders, autoimmune diseases, and cancer. Here, we review the historical development of marine pharmacology in the Eastern and Western worlds and describe the status of marine drug discovery. Finally, we discuss the importance of conducting sustainable exploitation of marine resources through biotechnology.

Nortopsentins as Leads from Marine Organisms for Anticancer and Anti-Inflammatory Agent Development

The marine environment is an excellent source of molecules that have a wide structural diversity and a variety of biological activities. Many marine natural products (MNPs) have been established as leads for anticancer drug discovery. Most of these compounds are alkaloids, including several chemical subclasses. In this review, we focus on the bis-indolyl alkaloid Nortopsentins and their derivatives with antiproliferative properties. Nortopsentins A-C were found to exhibit in vitro cytotoxicity against the P388 murine leukaemia cell line. Their structural manipulation provided a wide range of derivatives with significant anti-tumour activity against human cell lines derived from different cancer types (bladder, colon, gastric, CNS, liver, lung, breast, melanoma, ovarian, pancreatic, prostate, pleural mesothelioma, renal, sarcoma, and uterus). In vivo assays on animal models also proved that Nortopsentins and related bis-indolyl compounds have potent anti-inflammatory activity. These remarks set the foundation for future investigations into the development of new Nortopsentin derivatives as new anticancer and anti-inflammatory agents.

A Comparative Analysis of Mucus Immunomodulatory Properties from Seven Marine Gastropods from the Mediterranean Sea

The treatment of inflammatory and immune-related diseases due to dysfunctioning of the immune system necessitates modulation of the immune response through immunomodulatory compounds. Marine environments are considered as a new frontier for health benefit product implementations. Marine biodiversity is still a low explored resource, despite it is expected to represent an important platform for chemical bioactive compounds. Within the phylum Mollusca, gastropods are known to synthetize mucus, the latter presenting relevant bioactive properties, e.g., related to immunomodulant molecules able to activate the innate and acquired immune system. This study proposes a bioprospecting of the immunomodulant activity of mucus isolated from seven common gastropod species from the Gulf of Naples (Mediterranean Sea). Results showed that not all mucus displayed a significant cytotoxic activity on the two human cancer cell lines A549 and A2058. On the other hand, the mucus from Bolinus brandaris was strongly bioactive and was therefore thoroughly investigated at cellular, molecular, and protein levels on the human monocytes U937 line. It can conclusively induce monocyte differentiation in vitro and significantly stimulate natural immunity response.

Recent Discoveries on Marine Organism Immunomodulatory Activities

Marine organisms have been shown to be a valuable source for biologically active compounds for the prevention and treatment of cancer, inflammation, immune system diseases, and other pathologies. The advantage of studying organisms collected in the marine environment lies in their great biodiversity and in the variety of chemical structures of marine natural products. Various studies have focused on marine organism compounds with potential pharmaceutical applications, for instance, as immunomodulators, to treat cancer and immune-mediated diseases. Modulation of the immune system is defined as any change in the immune response that can result in the induction, expression, amplification, or inhibition of any phase of the immune response. Studies very often focus on the effects of marine-derived compounds on macrophages, as well as lymphocytes, by analyzing the release of mediators (cytokines) by using the immunological assay enzyme-linked immunosorbent assay (ELISA), Western blot, immunofluorescence, and real-time PCR. The main sources are fungi, bacteria, microalgae, macroalgae, sponges, mollusks, corals, and fishes. This review is focused on the marine-derived molecules discovered in the last three years as potential immunomodulatory drugs.

Anticancer effects of marine compounds blocking the nuclear factor kappa B signaling pathway

The abnormal expression of nuclear factor kappa B (NF-κB) target genes is closely related to the occurrence, metastasis, and invasion of tumor cells and is an inhibitor of their apoptosis. In recent years, the unique biodiversity in the marine environment has aroused great interest. Many studies indicate that some marine compounds exert anticancer effects on most common human tumors by modulating the NF-κB signaling pathway. In this study, 26 marine compounds that reduce cancer cell survival by suppressing the NF-κB signaling pathway were reviewed. They were derived from a wide range of sources, including sponges, fungi, algae and their derivatives or metabolites. These marine compounds exert antitumor effects through the canonical, noncanonical and atypical NF-κB signaling pathways; however, most of their anticancer targets and mechanisms remain unclear, and more research is needed in the future. Our article provides comprehensive information for researchers investigating the bioactivities of marine compounds and developing marine-derived anticancer drugs.

Marine-derived microbes and molecules for drug discovery

Increasing attention has been paid to marine-derived biomolecules as sources of therapeutics for autoimmune diseases. Nagasaki Prefecture has many islands and is surrounded by seas, straits, gulfs, bays, and coves, giving it the second longest coastline in Japan after Hokkaido. We have collected more than 20,000 marine microbes and have been preparing an original marine microbial extract library, which contains small and mid-size biomolecules that may penetrate cell membranes and interfere with the intracellular protein–protein interaction involved in the development of autoinflammatory diseases such as familial Mediterranean fever. In addition, we have been developing an indoor shark farming system to prepare shark nanobodies that could be developed as potential therapeutic agents for autoimmune diseases. Sharks produce heavy-chain antibodies, called immunoglobulin new antigen receptors (IgNARs), consisting of one variable domain (V_NAR) and five constant domains (C_NAR); of these, V_NAR can recognize a variety of foreign antigens. A V_NAR single domain fragment, called a nanobody, can be expressed in Escherichia coli and has the properties of an ideal therapeutic candidate for autoimmune diseases. Shark nanobodies contain complementarity-determining regions that are formed through the somatic rearrangement of variable, diversity, and joining segments, with the segment end trimming and the N- and P-additions, as found in the variable domains of mammalian antibodies. The affinity and diversity of shark nanobodies are thus expected to be comparable to those of mammalian antibodies. In addition, shark nanobodies are physically robust and can be prepared inexpensively; as such, they may lead to the development of highly specific, stable, effective, and inexpensive biotherapeutics in the future. In this review, we first summarize the history of the development of conventional small molecule drugs and monoclonal antibody therapeutics for autoimmune diseases, and then introduce our drug discovery system at Nagasaki University, including the preparation of an original marine microbial extract library and the development of shark nanobodies.

Metabolites with Antioxidant Activity from Marine Macroalgae

Reactive oxygen species (ROS) attack biological molecules, such as lipids, proteins, enzymes, DNA, and RNA, causing cellular and tissue damage. Hence, the disturbance of cellular antioxidant homeostasis can lead to oxidative stress and the onset of a plethora of diseases. Macroalgae, growing in stressful conditions under intense exposure to UV radiation, have developed protective mechanisms and have been recognized as an important source of secondary metabolites and macromolecules with antioxidant activity. In parallel, the fact that many algae can be cultivated in coastal areas ensures the provision of sufficient quantities of fine chemicals and biopolymers for commercial utilization, rendering them a viable source of antioxidants. This review focuses on the progress made concerning the discovery of antioxidant compounds derived from marine macroalgae, covering the literature up to December 2020. The present report presents the antioxidant potential and biogenetic origin of 301 macroalgal metabolites, categorized according to their chemical classes, highlighting the mechanisms of antioxidative action when known.

Protective Role of Mytilus edulis Hydrolysate in Lipopolysaccharide-Galactosamine Acute Liver Injury

Acute liver injury in its terminal phase trigger systemic inflammatory response syndrome with multiple organ failure. An uncontrolled inflammatory reaction is difficult to treat and contributes to high mortality. Therefore, to solve this problem a search for new therapeutic approaches remains urgent. This study aimed to explore the protective effects of M. edulis hydrolysate (N2-01) against Lipopolysaccharide-D-Galactosamine (LPS/D-GalN)-induced murine acute liver injure and the underlying mechanisms. N2-01 analysis, using Liquid Chromatography Mass Spectrometry (LCMS) metabolomic and proteomic platforms, confirmed composition, molecular-weight distribution, and high reproducibility between M. edulis hydrolysate manufactured batches. N2-01 efficiently protected mice against LPS/D-GalN-induced acute liver injury. The most prominent result (100% survival rate) was obtained by the constant subcutaneous administration of small doses of the drug. N2-01 decreased Vascular Cell Adhesion Molecule-1 (VCAM-1) expression from 4.648 ± 0.445 to 1.503 ± 0.091 Mean Fluorescence Intensity (MFI) and Interleukin-6 (IL-6) production in activated Human Umbilical Vein Endothelial Cells (HUVECs) from 7.473 ± 0.666 to 2.980 ± 0.130 ng/ml in vitro. The drug increased Nitric Oxide (NO) production by HUVECs from 27.203 ± 2.890 to 69.200 ± 4.716 MFI but significantly decreased inducible Nitric Oxide Synthase (iNOS) expression from 24.030 ± 2.776 to 15.300 ± 1.290 MFI and NO production by murine peritoneal lavage cells from 6.777 ± 0.373 µm to 2.175 ± 0.279 µm. The capability of the preparation to enhance the endothelium barrier function and to reduce vascular permeability was confirmed in Electrical Cell-substrate Impedance Sensor (ECIS) test in vitro and Miles assay in vivo. These results suggest N2-01 as a promising agent for treating a wide range of conditions associated with uncontrolled inflammation and endothelial dysfunction.

Rehabilitation of patients with chronic rhinosinusitis after functional endoscopic sinus surgery

Introduction. In the case of many patients with chronic rhinosinusitis (CRS), antibiotic and steroid therapies fail, and surgery is required. The recovery of patients after surgery equally depends on the postoperative behavior of each individual patient. The paper presents the outcomes of recovery after functional endoscopic sinus surgery (FESS) in a group of 74 patients. Methods. The study was conducted in patients undergoing surgical treatment by FESS, performed by the same surgeon. For the development of the statistical database, the clinical records were collected by the same investigator. Results. On the day of surgery and on the first postoperative day, 72.9% of patients reported facial pain, 41.8% nausea, 9.4% nasal bleeding, 8.8% vomiting. At 6 months postoperatively, 71.6% of patients estimated that they had a better quality of life than before surgery, 64.8% mentioned an improvement of olfaction as an effect, and 6.7% developed septal turbinate synechiae. Conclusions. No major complications were identified in the recovery of CRS patients after FESS. Postoperative facial pain was less well tolerated by young patients (18-35 years old). The improvement of smell and the increase of disease-specific quality of life are the most relevant results of recovery after FESS mentioned by the patients included in our study. The otorhinolaryngologist and the family doctor play an important role in the education of patients regarding the importance of treatment with mineral and thermal waters in post-FESS recovery. Keywords: chronic rhinosinusitis, endoscopic sinus surgery, FESS, rehabilitation, ERAS protocols,

Marine-Derived Biologically Active Compounds for the Potential Treatment of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic, systemic autoimmune disease with a prevalence rate of up to 1% and is significantly considered a common worldwide public health concern. Commercially, several traditional formulations are available to treat RA to some extent. However, these synthetic compounds exert toxicity and considerable side effects even at lower therapeutic concentrations. Considering the above-mentioned critiques, research is underway around the world in finding and exploiting potential alternatives. For instance, marine-derived biologically active compounds have gained much interest and are thus being extensively utilized to confront the confines of in practice counterparts, which have become ineffective for 21st-century medical settings. The utilization of naturally available bioactive compounds and their derivatives can minimize these synthetic compounds' problems to treat RA. Several marine-derived compounds exhibit anti-inflammatory and antioxidant properties and can be effectively used for therapeutic purposes against RA. The results of several studies ensured that the extraction of biologically active compounds from marine sources could provide a new and safe source for drug development against RA. Finally, current challenges, gaps, and future perspectives have been included in this review.

Marine-derived drugs: Recent advances in cancer therapy and immune signaling

The marine environment is an enormous source of marine-derived natural products (MNPs), and future investigation into anticancer drug discovery. Current progress in anticancer drugs offers a rise in isolation and clinical validation of numerous innovative developments and advances in anticancer therapy. However, only a limited number of FDA-approved marine-derived anticancer drugs are available due to several challenges and limitations highlighted here. The use of chitosan in developing marine-derived drugs is promising in the nanotech sector projected for a prolific anticancer drug delivery system (DDS). The cGAS-STING-mediated immune signaling pathway is crucial, which has not been significantly investigated in anticancer therapy and needs further attention. Additionally, a small range of anticancer mediators is currently involved in regulating various JAK/STAT signaling pathways, such as immunity, cell death, and tumor formation. This review addressed critical features associated with MNPs, origin, and development of anticancer drugs. Moreover, recent advances in the nanotech delivery of anticancer drugs and understanding into cancer immunity are detailed for improved human health.

Immunomodulatory Activity of the Marine Sponge, Haliclona (Soestella) sp. (Haplosclerida: Chalinidae), from Sri Lanka in Wistar Albino Rats: Immunosuppression and Th1-Skewed Cytokine Response

Natural secondary metabolites of sponges of the genus Haliclona are associated with an array of biological activity with therapeutic usage. We investigated the immunopharmacological properties of a presumably novel marine sponge species from Sri Lanka, Haliclona (Soestella) sp. Sponge material was collected from southern Sri Lanka by scuba diving. Sponge identification was based on spicule and skeleton morphology using light microscopy. Selected in vivo and ex vivo tests investigated nonfunctional and functional immunomodulatory activity of the Haliclona (Soestella) sp. crude extract (HSCE) in the Wistar rat model. Compared to the controls, rats orally gavaged daily for 14 consecutive days with 15 mg/kg dose of the HSCE manifested a significant reduction of immune cell counts of total WBCs (by 17%; p < 0.01), lymphocytes (38%), platelets (52%), splenocytes (20%), and bone marrow cells (BMC; 60%) (p < 0.001), with a concurrent increase in the neutrophil : lymphocyte ratio (p < 0.05); RBC counts abated by 53% (p < 0.001). A significant reduction of the splenosomatic index was evident with the 10 and 15 mg/kg doses (p < 0.001). Rat plasma TNF-α cytokine level was augmented by tenfold (p < 0.001), IL-6 level by twofold (p < 0.01) with the 15 mg/kg HSCE treatment, while IL-10 was detectable in rat plasma only with this treatment; the corresponding Th₁ : Th₂ cytokine ratio (TNF-α : IL-10) was indicative of an unequivocal Th1-skewed cytokine response (p < 0.01). Ex vivo bone marrow cell and splenocyte proliferation were significantly and dose dependently impaired by HSCE (IC₅₀ 0.719 and 0.931 μg/mL, respectively; p < 0.05). Subacute toxicity testing established that HSCE was devoid of general toxic, hepatotoxic, and nephrotoxic effects. In conclusion, HSCE was orally active, nontoxic, and effectively suppressed nonfunctional and functional immunological parameters of Wistar rats, suggestive of the potential use of the HSCE as an immunosuppressant drug lead.

Anti-Inflammatory Cembranoids from a Formosa Soft Coral Sarcophyton cherbonnieri

The present investigation on chemical constituents of the soft coral Sarcophyton cherbonnieri resulted in the isolation of seven new cembranoids, cherbonolides F–L (1–7). The chemical structures of 1–7 were determined by spectroscopic methods, including infrared, one- and two-dimensional (1D and 2D) NMR (COSY, HSQC, HMBC, and NOESY), MS experiments, and a chemical reduction of hydroperoxide by triphenylphosphine. The anti-inflammatory activities of 1–7 against neutrophil proinflammatory responses were evaluated by measuring their inhibitory ability toward N-formyl-methionyl-leucyl-phenylalanine/cytochalasin B (fMLF/CB)-induced superoxide anion generation and elastase release in primary human neutrophils. The results showed that all isolates exhibited moderate activities, while cherbonolide G (2) and cherbonolide H (3) displayed a more active effect than others on the inhibition of elastase release (48.2% ± 6.2%) and superoxide anion generation (44.5% ± 4.6%) at 30 µM, respectively.

In Vivo Evaluation of the Wound Healing Activity of Extracts and Bioactive Constituents of the Marine Isopod Ceratothoa oestroides

Wound healing is a fundamental response to tissue injury and a number of natural products has been found to accelerate the healing process. Herein, we report the preparation of a series of different polarity (organic and aqueous) extracts of the marine isopod Ceratothoa oestroides and the in vivo evaluation of their wound healing activity after topical administration of ointments incorporating the various extracts on wounds inflicted on SKH-hr1 hairless mice. The most active extract was fractionated for enrichment in the bioactive constituents and the fractions were further evaluated for their wound healing activity, while their chemical profiles were analyzed. Wound healing was evaluated by clinical assessment, photo-documentation, histopathological analysis and measurement of biophysical skin parameters, such as transepidermal water loss (TEWL), hydration, elasticity, and skin thickness. The highest levels of activity were exerted by treatment of the wounds with a fraction rich in eicosapentaenoic acid (EPA), as well as myristic and palmitoleic acids. Topical application of the bioactive fraction on the wounds of mice resulted in complete wound closure with a skin of almost normal architecture without any inflammatory elements.