Anti-inflammatory natural products modulate interleukins and their related signaling markers in inflammatory bowel disease: A systematic review.

This review aims to identify in vivo studies investigating the potential of plant substances and their natural molecules in managing inflammatory bowel disease (IBD). Specifically, the objective is to examine the impact of these substances on interleukins and other key inflammatory signaling markers. Relevant articles published up to December 2022 were identified through a search of the PubMed, Scopus, Web of Science, and Embase databases. The search used keywords including "inflammatory bowel disease", "medicinal plants", "natural molecules", "anti-inflammatory", and "ulcerative colitis", and identified 1,878 potentially relevant articles, of which 89 were included in this review after completion of the selection process. This study provides preclinical data on natural products (NPs) that can potentially treat IBD, including ulcerative colitis. The main actions of these NPs relate to their effects on nuclear factor kappa B (NF-κB), the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway, the regulation of T helper 17/regulatory T cells balance, and oxidative stress. The ability of these NPs to inhibit intestinal inflammation appears to be dependent on lowering levels of the pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1ß, and IL-17, via the Jun N-terminal kinase (JNK)1, NF-κß-p65, and STAT3 pathways. In addition, NPs were shown to reduce oxidative stress and the severity of ulcerative colitis, as well as increase the activity of antioxidant enzymes. These actions suggest that NPs represent a promising treatment for IBD, and potentially have greater efficacy and safety than current treatments.

Natural products modulating interleukins and other inflammatory mediators in tumor-bearing animals: A systematic review.

BACKGROUND: Cancer is a group of diseases characterized by abnormal cell growth and proliferation. Natural products are a potentially important source for bioactive phytochemicals in the management of cancer, which regulate a broad range of biological events via the modulation of interleukins (ILs), pro- and anti-inflammatory modulators, and other cancer hallmark-mediated signaling pathways. PURPOSE: To systematically review the literature to identify in vivo studies investigating the anticancer properties of medicinal plants and natural molecules as modulators of ILs and their related pro- and anti-inflammatory signaling markers in tumor-bearing animals. METHODS: Articles published in English were searched, without any constraint in respect of countries. The electronic databases PubMed, Embase, Scopus, and Web of Science were used for the literature search for studies published between January 2010 and January 2022. The search terms used included medicinal plants, anticancer, antineoplasic agent, ILs, cytokine, and their combinations. A manual search to detect any articles not found in the databases was also made. The identified studies were then critically reviewed and relevant data were extracted and summarized. RESULTS: Natural products were found to modulate ILs, including IL-1ß, IL-2, IL-4, IL-6, IL-8, IL-18, IL-23, and IL-12, and interferon gamma; increase tissue inhibitor metalloprotease; decrease vascular endothelial growth factor, tumor necrosis factor alpha, granulocyte macrophage colony-stimulating factor, and nuclear factor kappa B; augment immunity by increasing the major histocompatibility complexes II and CD4+, cluster of differentiation 8 + T cell and class II trans-activator expression; and heighten the action of antioxidant enzymes, which are involved in the detoxification of free radicals and reactive oxygen species. CONCLUSION: Natural products discussed in this review show great potential to regulate ILs and weaken associated pro- and anti-inflammatory signaling markers in tumor-bearing animals. Flavonoids, polyphenols, polysaccharides, alkaloids and tannins are important phytochemicals in the modulation of ILs, especially pro-inflammatory ones. However, in terms of future research, the importance of clinical trials to investigate their beneficial properties should be warranted.

Anti-inflammatory natural products as potential therapeutic agents of rheumatoid arthritis: A systematic review.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease causing severe locomotor disability and deterioration in the quality of life. Existing treatments for RA mainly focus on the use of immunomodulators and the suppression of synovial inflammation, and many have significant side effects. Medicinal plants are regarded as important alternative sources for treating RA. PURPOSE: This review summarizes the bioactive compounds of medicinal plants, which have been shown to modulate the immune response by regulating interleukins in vitro and in vivo experimental models, and that may be promising substances for use in the treatment of RA. METHODS: Articles on natural products used for the management of arthritis were retrieved from PubMed, Embase, Scopus, and Web of Science through electronic and manual search in English. In total, 576 publications were identified, and 34 were included in this systematic review. RESULTS: Two articles presented findings on the role of natural components in the treatment of arthritis in both in vitro and in vivo studies. Nine reports defined the role of plant-derived natural molecules in the treatment of arthritis using cell lines, and 27 in vivo studies assessed the anti-arthritic efficacy and immunomodulation effects of phytoconstituents on interleukin production and inflammatory responses. CONCLUSION: This systematic review broadly reports that, in contrast to other classes of phytochemicals, flavonoids have the greatest therapeutic potential against arthritis by modulating the expression of pro-inflammatory TNF-α, IL-1ß, IL-6, IL-8, and IL-17, as well as anti-inflammatory IL-2 and IL-10 cytokines, through the suppression of dynamic inflammatory biomarkers.

Inhibition of differentiation of monocyte to macrophages in atherosclerosis by oligomeric proanthocyanidins -In-vivo and in-vitro study.

Monocyte to macrophage differentiation is a key event in the progression of atherosclerosis. An understanding on the fundamental molecular mechanisms and the identification of regulatory mechanisms behind this differentiation may aid in the identification of new therapeutic strategies. Inhibition of this phenomenon will form first line of defense in the prevention and treatment of atherosclerosis. In the current study we explored hypercholesterolemia induced monocyte to macrophage differentiation in-vivo (Wistar rats) leading to atherosclerosis and OxyLDL, M-CSF induced monocyte differentiation in-vitro (U937 cells). Oligomeric proanthocyanidin (OPC) isolated from Crataegus oxyacantha was tested for its efficacy in downregulating this differentiation and in preventing atherogenic disturbances. Cholesterol cholic acid diet induced an increased monocyte to macrophage differentiation by upregulating MCP1 and VCAM1 which induced the inflammatory cytokines that further substantiated the monocyte conversion and infiltration into the vascular walls. On addition of OxyLDL and M-CSF to U937 cells, macrophage markers CD36 and CD 68, PPARγ, MMP2 and 9 were elevated, suggesting differentiation. OPC downregulated this differentiation and thus could prevent the initiation of atherosclerosis.