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ABSTRACT Background: : Atherosclerosis is an inflammatory disease that affects the arterial wall leading to myocardial, cerebral, and peripheral ischemic syndromes. The use of low doses of aspirin inhibits platelet [...]

Antineoplastic therapy has been associated with pain syndrome development characterized by acute and chronic pain. The chemotherapeutic agent dacarbazine, used mainly to treat metastatic melanoma, is reported to cause painful symptoms, compromising patient quality of life. Evidence has proposed that transient receptor potential ankyrin 1 (TRPA1) plays a critical role in chemotherapy-induced pain syndrome. Here, we investigated whether dacarbazine causes painful hypersensitivity in naive or melanoma-bearing mice and the involvement of TRPA1 in these models. Mouse dorsal root ganglion (DRG) neurons and human TRPA1-transfected HEK293 (hTRPA1-HEK293) cells were used to evaluate the TRPA1-mediated calcium response evoked by dacarbazine. Mechanical and cold allodynia were evaluated after acute or repeated dacarbazine administration in naive mice or after inoculation of B16-F10 melanoma cells in C57BL/6 mice. TRPA1 involvement was investigated by using pharmacological and genetic tools (selective antagonist or antisense oligonucleotide treatment and Trpa1 knockout mice). Dacarbazine directly activated TRPA1 in hTRPA1-HEK293 cells and mouse DRG neurons and appears to sensitize TRPA1 indirectly by generating oxidative stress products. Moreover, dacarbazine caused mechanical and cold allodynia in naive but not Trpa1 knockout mice. Also, dacarbazine-induced nociception was reduced by the pharmacological TRPA1 blockade (antagonism), antioxidants, and by ablation of TRPA1 expression. TRPA1 pharmacological blockade also reduced dacarbazine-induced nociception in a tumor-associated pain model. Thus, dacarbazine causes nociception by TRPA1 activation, indicating that this receptor may represent a pharmacological target for treating chemotherapy-induced pain syndrome in cancer patients submitted to antineoplastic treatment with dacarbazine., (© 2019 UICC.)

There is a major, unmet need for the treatment of cancer pain, and new targets and medicines are required. The transient receptor potential ankyrin 1 (TRPA1), a cation channel expressed by nociceptors, is activated by oxidizing substances to mediate pain-like responses in models of inflammatory and neuropathic pain. As cancer is known to increase oxidative stress, the role of TRPA1 was evaluated in a mouse model of cancer pain. Fourteen days after injection of B16-F10 murine melanoma cells into the plantar region of the right hind paw, C57BL/6 mice exhibited mechanical and thermal allodynia and thigmotaxis behavior. While heat allodynia was partially reduced in TRP vanilloid 1 (TRPV1)-deficient mice, thigmotaxis behavior and mechanical and cold allodynia were absent in TRPA1-deficient mice. Deletion of TRPA1 or TRPV1 did not affect cancer growth. Intrathecal TRPA1 antisense oligonucleotides and two different TRPA1 antagonists (HC-030031 or A967079) transiently attenuated thigmotaxis behavior and mechanical and cold allodynia. A TRPV1 antagonist (capsazepine) attenuated solely heat allodynia. NADPH oxidase activity and hydrogen peroxide levels were increased in hind paw skin 14 days after cancer cell inoculation. The antioxidant, α-lipoic acid, attenuated mechanical and cold allodynia and thigmotaxis behavior, but not heat allodynia. Whereas TRPV1, via an oxidative stress-independent pathway, contributes partially to heat hypersensitivity, oxidative stress-dependent activation of TRPA1 plays a key role in mediating thigmotaxis behavior and mechanical and cold allodynia in a cancer pain model. TRPA1 antagonists might be beneficial in the treatment of cancer pain., (© 2018 The Authors. International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.)

Cardiovascular diseases (CVD) are considered the leading cause of morbidity and mortality from chronic diseases in the world. In addition, about 20% of first and recurrent acute myocardial infarctions (MI) are silent. In this context, subclinical atherosclerosis culminates in evident CVD, through the evolution of early risk factors such as hypercholesterolemia, hypertriglyceridemia and others. The main problem in CVD is related to the long-time between the start of the subclinical atherosclerosis and the manifestation of the disease. The identification of subjects at risk of such events is obviously substantial, since identification leads to implementation and compliance with effective preventive measures that reduce such risk. In this sense, this review demonstrates biomarkers as an alternative to early detection of subclinical atherosclerosis. One of the proposed biomarkers is the Ischemia-modified albumin (IMA), being considered a promising biochemical biomarker for atherosclerotic conditions. Another marker that is gaining strength and is associated with the IMA are the advanced oxidation protein products (AOPP), its measurement provides information on the level of exposure to potentially harmful changes to proteins and metabolic control. And last but not least we have nitric oxide as an early marker mainly related to endothelial dysfunction. In this review also is evidenced the use of the Campomanesia xanthocarpa, a plant native to southern region from Brazil extensively used as complementary and alternative medicine, and natural products to reduce protein oxidation and improve the availability of nitric oxide and consequently vascular function, reducing the risk for development of CVD.